xref: /openbmc/linux/drivers/scsi/libsas/sas_ata.c (revision 3db55767)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Support for SATA devices on Serial Attached SCSI (SAS) controllers
4  *
5  * Copyright (C) 2006 IBM Corporation
6  *
7  * Written by: Darrick J. Wong <djwong@us.ibm.com>, IBM Corporation
8  */
9 
10 #include <linux/scatterlist.h>
11 #include <linux/slab.h>
12 #include <linux/async.h>
13 #include <linux/export.h>
14 
15 #include <scsi/sas_ata.h>
16 #include "sas_internal.h"
17 #include <scsi/scsi_host.h>
18 #include <scsi/scsi_device.h>
19 #include <scsi/scsi_tcq.h>
20 #include <scsi/scsi.h>
21 #include <scsi/scsi_transport.h>
22 #include <scsi/scsi_transport_sas.h>
23 #include "scsi_sas_internal.h"
24 #include "scsi_transport_api.h"
25 #include <scsi/scsi_eh.h>
26 
27 static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
28 {
29 	/* Cheesy attempt to translate SAS errors into ATA.  Hah! */
30 
31 	/* transport error */
32 	if (ts->resp == SAS_TASK_UNDELIVERED)
33 		return AC_ERR_ATA_BUS;
34 
35 	/* ts->resp == SAS_TASK_COMPLETE */
36 	/* task delivered, what happened afterwards? */
37 	switch (ts->stat) {
38 	case SAS_DEV_NO_RESPONSE:
39 		return AC_ERR_TIMEOUT;
40 	case SAS_INTERRUPTED:
41 	case SAS_PHY_DOWN:
42 	case SAS_NAK_R_ERR:
43 		return AC_ERR_ATA_BUS;
44 	case SAS_DATA_UNDERRUN:
45 		/*
46 		 * Some programs that use the taskfile interface
47 		 * (smartctl in particular) can cause underrun
48 		 * problems.  Ignore these errors, perhaps at our
49 		 * peril.
50 		 */
51 		return 0;
52 	case SAS_DATA_OVERRUN:
53 	case SAS_QUEUE_FULL:
54 	case SAS_DEVICE_UNKNOWN:
55 	case SAS_OPEN_TO:
56 	case SAS_OPEN_REJECT:
57 		pr_warn("%s: Saw error %d.  What to do?\n",
58 			__func__, ts->stat);
59 		return AC_ERR_OTHER;
60 	case SAM_STAT_CHECK_CONDITION:
61 	case SAS_ABORTED_TASK:
62 		return AC_ERR_DEV;
63 	case SAS_PROTO_RESPONSE:
64 		/* This means the ending_fis has the error
65 		 * value; return 0 here to collect it
66 		 */
67 		return 0;
68 	default:
69 		return 0;
70 	}
71 }
72 
73 static void sas_ata_task_done(struct sas_task *task)
74 {
75 	struct ata_queued_cmd *qc = task->uldd_task;
76 	struct domain_device *dev = task->dev;
77 	struct task_status_struct *stat = &task->task_status;
78 	struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
79 	struct sas_ha_struct *sas_ha = dev->port->ha;
80 	enum ata_completion_errors ac;
81 	unsigned long flags;
82 	struct ata_link *link;
83 	struct ata_port *ap;
84 
85 	spin_lock_irqsave(&dev->done_lock, flags);
86 	if (test_bit(SAS_HA_FROZEN, &sas_ha->state))
87 		task = NULL;
88 	else if (qc && qc->scsicmd)
89 		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
90 	spin_unlock_irqrestore(&dev->done_lock, flags);
91 
92 	/* check if libsas-eh got to the task before us */
93 	if (unlikely(!task))
94 		return;
95 
96 	if (!qc)
97 		goto qc_already_gone;
98 
99 	ap = qc->ap;
100 	link = &ap->link;
101 
102 	spin_lock_irqsave(ap->lock, flags);
103 	/* check if we lost the race with libata/sas_ata_post_internal() */
104 	if (unlikely(ata_port_is_frozen(ap))) {
105 		spin_unlock_irqrestore(ap->lock, flags);
106 		if (qc->scsicmd)
107 			goto qc_already_gone;
108 		else {
109 			/* if eh is not involved and the port is frozen then the
110 			 * ata internal abort process has taken responsibility
111 			 * for this sas_task
112 			 */
113 			return;
114 		}
115 	}
116 
117 	if (stat->stat == SAS_PROTO_RESPONSE ||
118 	    stat->stat == SAS_SAM_STAT_GOOD ||
119 	    (stat->stat == SAS_SAM_STAT_CHECK_CONDITION &&
120 	      dev->sata_dev.class == ATA_DEV_ATAPI)) {
121 		memcpy(dev->sata_dev.fis, resp->ending_fis, ATA_RESP_FIS_SIZE);
122 
123 		if (!link->sactive) {
124 			qc->err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
125 		} else {
126 			link->eh_info.err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
127 			if (unlikely(link->eh_info.err_mask))
128 				qc->flags |= ATA_QCFLAG_EH;
129 		}
130 	} else {
131 		ac = sas_to_ata_err(stat);
132 		if (ac) {
133 			pr_warn("%s: SAS error 0x%x\n", __func__, stat->stat);
134 			/* We saw a SAS error. Send a vague error. */
135 			if (!link->sactive) {
136 				qc->err_mask = ac;
137 			} else {
138 				link->eh_info.err_mask |= AC_ERR_DEV;
139 				qc->flags |= ATA_QCFLAG_EH;
140 			}
141 
142 			dev->sata_dev.fis[2] = ATA_ERR | ATA_DRDY; /* tf status */
143 			dev->sata_dev.fis[3] = ATA_ABORTED; /* tf error */
144 		}
145 	}
146 
147 	qc->lldd_task = NULL;
148 	ata_qc_complete(qc);
149 	spin_unlock_irqrestore(ap->lock, flags);
150 
151 qc_already_gone:
152 	sas_free_task(task);
153 }
154 
155 static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
156 	__must_hold(ap->lock)
157 {
158 	struct sas_task *task;
159 	struct scatterlist *sg;
160 	int ret = AC_ERR_SYSTEM;
161 	unsigned int si, xfer = 0;
162 	struct ata_port *ap = qc->ap;
163 	struct domain_device *dev = ap->private_data;
164 	struct sas_ha_struct *sas_ha = dev->port->ha;
165 	struct Scsi_Host *host = sas_ha->core.shost;
166 	struct sas_internal *i = to_sas_internal(host->transportt);
167 
168 	/* TODO: we should try to remove that unlock */
169 	spin_unlock(ap->lock);
170 
171 	/* If the device fell off, no sense in issuing commands */
172 	if (test_bit(SAS_DEV_GONE, &dev->state))
173 		goto out;
174 
175 	task = sas_alloc_task(GFP_ATOMIC);
176 	if (!task)
177 		goto out;
178 	task->dev = dev;
179 	task->task_proto = SAS_PROTOCOL_STP;
180 	task->task_done = sas_ata_task_done;
181 
182 	/* For NCQ commands, zero out the tag libata assigned us */
183 	if (ata_is_ncq(qc->tf.protocol))
184 		qc->tf.nsect = 0;
185 
186 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, (u8 *)&task->ata_task.fis);
187 	task->uldd_task = qc;
188 	if (ata_is_atapi(qc->tf.protocol)) {
189 		memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
190 		task->total_xfer_len = qc->nbytes;
191 		task->num_scatter = qc->n_elem;
192 		task->data_dir = qc->dma_dir;
193 	} else if (!ata_is_data(qc->tf.protocol)) {
194 		task->data_dir = DMA_NONE;
195 	} else {
196 		for_each_sg(qc->sg, sg, qc->n_elem, si)
197 			xfer += sg_dma_len(sg);
198 
199 		task->total_xfer_len = xfer;
200 		task->num_scatter = si;
201 		task->data_dir = qc->dma_dir;
202 	}
203 	task->scatter = qc->sg;
204 	task->ata_task.retry_count = 1;
205 	qc->lldd_task = task;
206 
207 	task->ata_task.use_ncq = ata_is_ncq(qc->tf.protocol);
208 	task->ata_task.dma_xfer = ata_is_dma(qc->tf.protocol);
209 
210 	if (qc->scsicmd)
211 		ASSIGN_SAS_TASK(qc->scsicmd, task);
212 
213 	ret = i->dft->lldd_execute_task(task, GFP_ATOMIC);
214 	if (ret) {
215 		pr_debug("lldd_execute_task returned: %d\n", ret);
216 
217 		if (qc->scsicmd)
218 			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
219 		sas_free_task(task);
220 		qc->lldd_task = NULL;
221 		ret = AC_ERR_SYSTEM;
222 	}
223 
224  out:
225 	spin_lock(ap->lock);
226 	return ret;
227 }
228 
229 static void sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
230 {
231 	struct domain_device *dev = qc->ap->private_data;
232 
233 	ata_tf_from_fis(dev->sata_dev.fis, &qc->result_tf);
234 }
235 
236 static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
237 {
238 	return to_sas_internal(dev->port->ha->core.shost->transportt);
239 }
240 
241 static int sas_get_ata_command_set(struct domain_device *dev)
242 {
243 	struct ata_taskfile tf;
244 
245 	if (dev->dev_type == SAS_SATA_PENDING)
246 		return ATA_DEV_UNKNOWN;
247 
248 	ata_tf_from_fis(dev->frame_rcvd, &tf);
249 
250 	return ata_dev_classify(&tf);
251 }
252 
253 int sas_get_ata_info(struct domain_device *dev, struct ex_phy *phy)
254 {
255 	if (phy->attached_tproto & SAS_PROTOCOL_STP)
256 		dev->tproto = phy->attached_tproto;
257 	if (phy->attached_sata_dev)
258 		dev->tproto |= SAS_SATA_DEV;
259 
260 	if (phy->attached_dev_type == SAS_SATA_PENDING)
261 		dev->dev_type = SAS_SATA_PENDING;
262 	else {
263 		int res;
264 
265 		dev->dev_type = SAS_SATA_DEV;
266 		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
267 					      &dev->sata_dev.rps_resp);
268 		if (res) {
269 			pr_debug("report phy sata to %016llx:%02d returned 0x%x\n",
270 				 SAS_ADDR(dev->parent->sas_addr),
271 				 phy->phy_id, res);
272 			return res;
273 		}
274 		memcpy(dev->frame_rcvd, &dev->sata_dev.rps_resp.rps.fis,
275 		       sizeof(struct dev_to_host_fis));
276 		dev->sata_dev.class = sas_get_ata_command_set(dev);
277 	}
278 	return 0;
279 }
280 
281 static int sas_ata_clear_pending(struct domain_device *dev, struct ex_phy *phy)
282 {
283 	int res;
284 
285 	/* we weren't pending, so successfully end the reset sequence now */
286 	if (dev->dev_type != SAS_SATA_PENDING)
287 		return 1;
288 
289 	/* hmmm, if this succeeds do we need to repost the domain_device to the
290 	 * lldd so it can pick up new parameters?
291 	 */
292 	res = sas_get_ata_info(dev, phy);
293 	if (res)
294 		return 0; /* retry */
295 	else
296 		return 1;
297 }
298 
299 int smp_ata_check_ready_type(struct ata_link *link)
300 {
301 	struct domain_device *dev = link->ap->private_data;
302 	struct sas_phy *phy = sas_get_local_phy(dev);
303 	struct domain_device *ex_dev = dev->parent;
304 	enum sas_device_type type = SAS_PHY_UNUSED;
305 	u8 sas_addr[SAS_ADDR_SIZE];
306 	int res;
307 
308 	res = sas_get_phy_attached_dev(ex_dev, phy->number, sas_addr, &type);
309 	sas_put_local_phy(phy);
310 	if (res)
311 		return res;
312 
313 	switch (type) {
314 	case SAS_SATA_PENDING:
315 		return 0;
316 	case SAS_END_DEVICE:
317 		return 1;
318 	default:
319 		return -ENODEV;
320 	}
321 }
322 EXPORT_SYMBOL_GPL(smp_ata_check_ready_type);
323 
324 static int smp_ata_check_ready(struct ata_link *link)
325 {
326 	int res;
327 	struct ata_port *ap = link->ap;
328 	struct domain_device *dev = ap->private_data;
329 	struct domain_device *ex_dev = dev->parent;
330 	struct sas_phy *phy = sas_get_local_phy(dev);
331 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy->number];
332 
333 	res = sas_ex_phy_discover(ex_dev, phy->number);
334 	sas_put_local_phy(phy);
335 
336 	/* break the wait early if the expander is unreachable,
337 	 * otherwise keep polling
338 	 */
339 	if (res == -ECOMM)
340 		return res;
341 	if (res != SMP_RESP_FUNC_ACC)
342 		return 0;
343 
344 	switch (ex_phy->attached_dev_type) {
345 	case SAS_SATA_PENDING:
346 		return 0;
347 	case SAS_END_DEVICE:
348 		if (ex_phy->attached_sata_dev)
349 			return sas_ata_clear_pending(dev, ex_phy);
350 		fallthrough;
351 	default:
352 		return -ENODEV;
353 	}
354 }
355 
356 static int local_ata_check_ready(struct ata_link *link)
357 {
358 	struct ata_port *ap = link->ap;
359 	struct domain_device *dev = ap->private_data;
360 	struct sas_internal *i = dev_to_sas_internal(dev);
361 
362 	if (i->dft->lldd_ata_check_ready)
363 		return i->dft->lldd_ata_check_ready(dev);
364 	else {
365 		/* lldd's that don't implement 'ready' checking get the
366 		 * old default behavior of not coordinating reset
367 		 * recovery with libata
368 		 */
369 		return 1;
370 	}
371 }
372 
373 static int sas_ata_printk(const char *level, const struct domain_device *ddev,
374 			  const char *fmt, ...)
375 {
376 	struct ata_port *ap = ddev->sata_dev.ap;
377 	struct device *dev = &ddev->rphy->dev;
378 	struct va_format vaf;
379 	va_list args;
380 	int r;
381 
382 	va_start(args, fmt);
383 
384 	vaf.fmt = fmt;
385 	vaf.va = &args;
386 
387 	r = printk("%s" SAS_FMT "ata%u: %s: %pV",
388 		   level, ap->print_id, dev_name(dev), &vaf);
389 
390 	va_end(args);
391 
392 	return r;
393 }
394 
395 static int sas_ata_wait_after_reset(struct domain_device *dev, unsigned long deadline)
396 {
397 	struct sata_device *sata_dev = &dev->sata_dev;
398 	int (*check_ready)(struct ata_link *link);
399 	struct ata_port *ap = sata_dev->ap;
400 	struct ata_link *link = &ap->link;
401 	struct sas_phy *phy;
402 	int ret;
403 
404 	phy = sas_get_local_phy(dev);
405 	if (scsi_is_sas_phy_local(phy))
406 		check_ready = local_ata_check_ready;
407 	else
408 		check_ready = smp_ata_check_ready;
409 	sas_put_local_phy(phy);
410 
411 	ret = ata_wait_after_reset(link, deadline, check_ready);
412 	if (ret && ret != -EAGAIN)
413 		sas_ata_printk(KERN_ERR, dev, "reset failed (errno=%d)\n", ret);
414 
415 	return ret;
416 }
417 
418 static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
419 			      unsigned long deadline)
420 {
421 	struct ata_port *ap = link->ap;
422 	struct domain_device *dev = ap->private_data;
423 	struct sas_internal *i = dev_to_sas_internal(dev);
424 	int ret;
425 
426 	ret = i->dft->lldd_I_T_nexus_reset(dev);
427 	if (ret == -ENODEV)
428 		return ret;
429 
430 	if (ret != TMF_RESP_FUNC_COMPLETE)
431 		sas_ata_printk(KERN_DEBUG, dev, "Unable to reset ata device?\n");
432 
433 	ret = sas_ata_wait_after_reset(dev, deadline);
434 
435 	*class = dev->sata_dev.class;
436 
437 	ap->cbl = ATA_CBL_SATA;
438 	return ret;
439 }
440 
441 /*
442  * notify the lldd to forget the sas_task for this internal ata command
443  * that bypasses scsi-eh
444  */
445 static void sas_ata_internal_abort(struct sas_task *task)
446 {
447 	struct sas_internal *si = dev_to_sas_internal(task->dev);
448 	unsigned long flags;
449 	int res;
450 
451 	spin_lock_irqsave(&task->task_state_lock, flags);
452 	if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
453 	    task->task_state_flags & SAS_TASK_STATE_DONE) {
454 		spin_unlock_irqrestore(&task->task_state_lock, flags);
455 		pr_debug("%s: Task %p already finished.\n", __func__, task);
456 		goto out;
457 	}
458 	task->task_state_flags |= SAS_TASK_STATE_ABORTED;
459 	spin_unlock_irqrestore(&task->task_state_lock, flags);
460 
461 	res = si->dft->lldd_abort_task(task);
462 
463 	spin_lock_irqsave(&task->task_state_lock, flags);
464 	if (task->task_state_flags & SAS_TASK_STATE_DONE ||
465 	    res == TMF_RESP_FUNC_COMPLETE) {
466 		spin_unlock_irqrestore(&task->task_state_lock, flags);
467 		goto out;
468 	}
469 
470 	/* XXX we are not prepared to deal with ->lldd_abort_task()
471 	 * failures.  TODO: lldds need to unconditionally forget about
472 	 * aborted ata tasks, otherwise we (likely) leak the sas task
473 	 * here
474 	 */
475 	pr_warn("%s: Task %p leaked.\n", __func__, task);
476 
477 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
478 		task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
479 	spin_unlock_irqrestore(&task->task_state_lock, flags);
480 
481 	return;
482  out:
483 	sas_free_task(task);
484 }
485 
486 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
487 {
488 	if (qc->flags & ATA_QCFLAG_EH)
489 		qc->err_mask |= AC_ERR_OTHER;
490 
491 	if (qc->err_mask) {
492 		/*
493 		 * Find the sas_task and kill it.  By this point, libata
494 		 * has decided to kill the qc and has frozen the port.
495 		 * In this state sas_ata_task_done() will no longer free
496 		 * the sas_task, so we need to notify the lldd (via
497 		 * ->lldd_abort_task) that the task is dead and free it
498 		 *  ourselves.
499 		 */
500 		struct sas_task *task = qc->lldd_task;
501 
502 		qc->lldd_task = NULL;
503 		if (!task)
504 			return;
505 		task->uldd_task = NULL;
506 		sas_ata_internal_abort(task);
507 	}
508 }
509 
510 
511 static void sas_ata_set_dmamode(struct ata_port *ap, struct ata_device *ata_dev)
512 {
513 	struct domain_device *dev = ap->private_data;
514 	struct sas_internal *i = dev_to_sas_internal(dev);
515 
516 	if (i->dft->lldd_ata_set_dmamode)
517 		i->dft->lldd_ata_set_dmamode(dev);
518 }
519 
520 static void sas_ata_sched_eh(struct ata_port *ap)
521 {
522 	struct domain_device *dev = ap->private_data;
523 	struct sas_ha_struct *ha = dev->port->ha;
524 	unsigned long flags;
525 
526 	spin_lock_irqsave(&ha->lock, flags);
527 	if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
528 		ha->eh_active++;
529 	ata_std_sched_eh(ap);
530 	spin_unlock_irqrestore(&ha->lock, flags);
531 }
532 
533 void sas_ata_end_eh(struct ata_port *ap)
534 {
535 	struct domain_device *dev = ap->private_data;
536 	struct sas_ha_struct *ha = dev->port->ha;
537 	unsigned long flags;
538 
539 	spin_lock_irqsave(&ha->lock, flags);
540 	if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
541 		ha->eh_active--;
542 	spin_unlock_irqrestore(&ha->lock, flags);
543 }
544 
545 static int sas_ata_prereset(struct ata_link *link, unsigned long deadline)
546 {
547 	struct ata_port *ap = link->ap;
548 	struct domain_device *dev = ap->private_data;
549 	struct sas_phy *local_phy = sas_get_local_phy(dev);
550 	int res = 0;
551 
552 	if (!local_phy->enabled || test_bit(SAS_DEV_GONE, &dev->state))
553 		res = -ENOENT;
554 	sas_put_local_phy(local_phy);
555 
556 	return res;
557 }
558 
559 static struct ata_port_operations sas_sata_ops = {
560 	.prereset		= sas_ata_prereset,
561 	.hardreset		= sas_ata_hard_reset,
562 	.error_handler		= ata_std_error_handler,
563 	.post_internal_cmd	= sas_ata_post_internal,
564 	.qc_defer               = ata_std_qc_defer,
565 	.qc_prep		= ata_noop_qc_prep,
566 	.qc_issue		= sas_ata_qc_issue,
567 	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
568 	.port_start		= ata_sas_port_start,
569 	.port_stop		= ata_sas_port_stop,
570 	.set_dmamode		= sas_ata_set_dmamode,
571 	.sched_eh		= sas_ata_sched_eh,
572 	.end_eh			= sas_ata_end_eh,
573 };
574 
575 static struct ata_port_info sata_port_info = {
576 	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
577 		 ATA_FLAG_SAS_HOST | ATA_FLAG_FPDMA_AUX,
578 	.pio_mask = ATA_PIO4,
579 	.mwdma_mask = ATA_MWDMA2,
580 	.udma_mask = ATA_UDMA6,
581 	.port_ops = &sas_sata_ops
582 };
583 
584 int sas_ata_init(struct domain_device *found_dev)
585 {
586 	struct sas_ha_struct *ha = found_dev->port->ha;
587 	struct Scsi_Host *shost = ha->core.shost;
588 	struct ata_host *ata_host;
589 	struct ata_port *ap;
590 	int rc;
591 
592 	ata_host = kzalloc(sizeof(*ata_host), GFP_KERNEL);
593 	if (!ata_host)	{
594 		pr_err("ata host alloc failed.\n");
595 		return -ENOMEM;
596 	}
597 
598 	ata_host_init(ata_host, ha->dev, &sas_sata_ops);
599 
600 	ap = ata_sas_port_alloc(ata_host, &sata_port_info, shost);
601 	if (!ap) {
602 		pr_err("ata_sas_port_alloc failed.\n");
603 		rc = -ENODEV;
604 		goto free_host;
605 	}
606 
607 	ap->private_data = found_dev;
608 	ap->cbl = ATA_CBL_SATA;
609 	ap->scsi_host = shost;
610 	rc = ata_sas_port_init(ap);
611 	if (rc)
612 		goto destroy_port;
613 
614 	rc = ata_sas_tport_add(ata_host->dev, ap);
615 	if (rc)
616 		goto destroy_port;
617 
618 	found_dev->sata_dev.ata_host = ata_host;
619 	found_dev->sata_dev.ap = ap;
620 
621 	return 0;
622 
623 destroy_port:
624 	ata_sas_port_destroy(ap);
625 free_host:
626 	ata_host_put(ata_host);
627 	return rc;
628 }
629 
630 void sas_ata_task_abort(struct sas_task *task)
631 {
632 	struct ata_queued_cmd *qc = task->uldd_task;
633 	struct completion *waiting;
634 
635 	/* Bounce SCSI-initiated commands to the SCSI EH */
636 	if (qc->scsicmd) {
637 		blk_abort_request(scsi_cmd_to_rq(qc->scsicmd));
638 		return;
639 	}
640 
641 	/* Internal command, fake a timeout and complete. */
642 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
643 	qc->flags |= ATA_QCFLAG_EH;
644 	qc->err_mask |= AC_ERR_TIMEOUT;
645 	waiting = qc->private_data;
646 	complete(waiting);
647 }
648 
649 void sas_probe_sata(struct asd_sas_port *port)
650 {
651 	struct domain_device *dev, *n;
652 
653 	mutex_lock(&port->ha->disco_mutex);
654 	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
655 		if (!dev_is_sata(dev))
656 			continue;
657 
658 		ata_sas_async_probe(dev->sata_dev.ap);
659 	}
660 	mutex_unlock(&port->ha->disco_mutex);
661 
662 	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
663 		if (!dev_is_sata(dev))
664 			continue;
665 
666 		sas_ata_wait_eh(dev);
667 
668 		/* if libata could not bring the link up, don't surface
669 		 * the device
670 		 */
671 		if (!ata_dev_enabled(sas_to_ata_dev(dev)))
672 			sas_fail_probe(dev, __func__, -ENODEV);
673 	}
674 
675 }
676 
677 int sas_ata_add_dev(struct domain_device *parent, struct ex_phy *phy,
678 		    struct domain_device *child, int phy_id)
679 {
680 	struct sas_rphy *rphy;
681 	int ret;
682 
683 	if (child->linkrate > parent->min_linkrate) {
684 		struct sas_phy *cphy = child->phy;
685 		enum sas_linkrate min_prate = cphy->minimum_linkrate,
686 			parent_min_lrate = parent->min_linkrate,
687 			min_linkrate = (min_prate > parent_min_lrate) ?
688 					parent_min_lrate : 0;
689 		struct sas_phy_linkrates rates = {
690 			.maximum_linkrate = parent->min_linkrate,
691 			.minimum_linkrate = min_linkrate,
692 		};
693 
694 		pr_notice("ex %016llx phy%02d SATA device linkrate > min pathway connection rate, attempting to lower device linkrate\n",
695 			  SAS_ADDR(child->sas_addr), phy_id);
696 		ret = sas_smp_phy_control(parent, phy_id,
697 					  PHY_FUNC_LINK_RESET, &rates);
698 		if (ret) {
699 			pr_err("ex %016llx phy%02d SATA device could not set linkrate (%d)\n",
700 			       SAS_ADDR(child->sas_addr), phy_id, ret);
701 			return ret;
702 		}
703 		pr_notice("ex %016llx phy%02d SATA device set linkrate successfully\n",
704 			  SAS_ADDR(child->sas_addr), phy_id);
705 		child->linkrate = child->min_linkrate;
706 	}
707 	ret = sas_get_ata_info(child, phy);
708 	if (ret)
709 		return ret;
710 
711 	sas_init_dev(child);
712 	ret = sas_ata_init(child);
713 	if (ret)
714 		return ret;
715 
716 	rphy = sas_end_device_alloc(phy->port);
717 	if (!rphy)
718 		return -ENOMEM;
719 
720 	rphy->identify.phy_identifier = phy_id;
721 	child->rphy = rphy;
722 	get_device(&rphy->dev);
723 
724 	list_add_tail(&child->disco_list_node, &parent->port->disco_list);
725 
726 	ret = sas_discover_sata(child);
727 	if (ret) {
728 		pr_notice("sas_discover_sata() for device %16llx at %016llx:%02d returned 0x%x\n",
729 			  SAS_ADDR(child->sas_addr),
730 			  SAS_ADDR(parent->sas_addr), phy_id, ret);
731 		sas_rphy_free(child->rphy);
732 		list_del(&child->disco_list_node);
733 		return ret;
734 	}
735 
736 	return 0;
737 }
738 
739 static void sas_ata_flush_pm_eh(struct asd_sas_port *port, const char *func)
740 {
741 	struct domain_device *dev, *n;
742 
743 	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
744 		if (!dev_is_sata(dev))
745 			continue;
746 
747 		sas_ata_wait_eh(dev);
748 
749 		/* if libata failed to power manage the device, tear it down */
750 		if (ata_dev_disabled(sas_to_ata_dev(dev)))
751 			sas_fail_probe(dev, func, -ENODEV);
752 	}
753 }
754 
755 void sas_suspend_sata(struct asd_sas_port *port)
756 {
757 	struct domain_device *dev;
758 
759 	mutex_lock(&port->ha->disco_mutex);
760 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
761 		struct sata_device *sata;
762 
763 		if (!dev_is_sata(dev))
764 			continue;
765 
766 		sata = &dev->sata_dev;
767 		if (sata->ap->pm_mesg.event == PM_EVENT_SUSPEND)
768 			continue;
769 
770 		ata_sas_port_suspend(sata->ap);
771 	}
772 	mutex_unlock(&port->ha->disco_mutex);
773 
774 	sas_ata_flush_pm_eh(port, __func__);
775 }
776 
777 void sas_resume_sata(struct asd_sas_port *port)
778 {
779 	struct domain_device *dev;
780 
781 	mutex_lock(&port->ha->disco_mutex);
782 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
783 		struct sata_device *sata;
784 
785 		if (!dev_is_sata(dev))
786 			continue;
787 
788 		sata = &dev->sata_dev;
789 		if (sata->ap->pm_mesg.event == PM_EVENT_ON)
790 			continue;
791 
792 		ata_sas_port_resume(sata->ap);
793 	}
794 	mutex_unlock(&port->ha->disco_mutex);
795 
796 	sas_ata_flush_pm_eh(port, __func__);
797 }
798 
799 /**
800  * sas_discover_sata - discover an STP/SATA domain device
801  * @dev: pointer to struct domain_device of interest
802  *
803  * Devices directly attached to a HA port, have no parents.  All other
804  * devices do, and should have their "parent" pointer set appropriately
805  * before calling this function.
806  */
807 int sas_discover_sata(struct domain_device *dev)
808 {
809 	if (dev->dev_type == SAS_SATA_PM)
810 		return -ENODEV;
811 
812 	dev->sata_dev.class = sas_get_ata_command_set(dev);
813 	sas_fill_in_rphy(dev, dev->rphy);
814 
815 	return sas_notify_lldd_dev_found(dev);
816 }
817 
818 static void async_sas_ata_eh(void *data, async_cookie_t cookie)
819 {
820 	struct domain_device *dev = data;
821 	struct ata_port *ap = dev->sata_dev.ap;
822 	struct sas_ha_struct *ha = dev->port->ha;
823 
824 	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
825 	ata_scsi_port_error_handler(ha->core.shost, ap);
826 	sas_put_device(dev);
827 }
828 
829 void sas_ata_strategy_handler(struct Scsi_Host *shost)
830 {
831 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
832 	ASYNC_DOMAIN_EXCLUSIVE(async);
833 	int i;
834 
835 	/* it's ok to defer revalidation events during ata eh, these
836 	 * disks are in one of three states:
837 	 * 1/ present for initial domain discovery, and these
838 	 *    resets will cause bcn flutters
839 	 * 2/ hot removed, we'll discover that after eh fails
840 	 * 3/ hot added after initial discovery, lost the race, and need
841 	 *    to catch the next train.
842 	 */
843 	sas_disable_revalidation(sas_ha);
844 
845 	spin_lock_irq(&sas_ha->phy_port_lock);
846 	for (i = 0; i < sas_ha->num_phys; i++) {
847 		struct asd_sas_port *port = sas_ha->sas_port[i];
848 		struct domain_device *dev;
849 
850 		spin_lock(&port->dev_list_lock);
851 		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
852 			if (!dev_is_sata(dev))
853 				continue;
854 
855 			/* hold a reference over eh since we may be
856 			 * racing with final remove once all commands
857 			 * are completed
858 			 */
859 			kref_get(&dev->kref);
860 
861 			async_schedule_domain(async_sas_ata_eh, dev, &async);
862 		}
863 		spin_unlock(&port->dev_list_lock);
864 	}
865 	spin_unlock_irq(&sas_ha->phy_port_lock);
866 
867 	async_synchronize_full_domain(&async);
868 
869 	sas_enable_revalidation(sas_ha);
870 }
871 
872 void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q)
873 {
874 	struct scsi_cmnd *cmd, *n;
875 	struct domain_device *eh_dev;
876 
877 	do {
878 		LIST_HEAD(sata_q);
879 		eh_dev = NULL;
880 
881 		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
882 			struct domain_device *ddev = cmd_to_domain_dev(cmd);
883 
884 			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
885 				continue;
886 			if (eh_dev && eh_dev != ddev)
887 				continue;
888 			eh_dev = ddev;
889 			list_move(&cmd->eh_entry, &sata_q);
890 		}
891 
892 		if (!list_empty(&sata_q)) {
893 			struct ata_port *ap = eh_dev->sata_dev.ap;
894 
895 			sas_ata_printk(KERN_DEBUG, eh_dev, "cmd error handler\n");
896 			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
897 			/*
898 			 * ata's error handler may leave the cmd on the list
899 			 * so make sure they don't remain on a stack list
900 			 * about to go out of scope.
901 			 *
902 			 * This looks strange, since the commands are
903 			 * now part of no list, but the next error
904 			 * action will be ata_port_error_handler()
905 			 * which takes no list and sweeps them up
906 			 * anyway from the ata tag array.
907 			 */
908 			while (!list_empty(&sata_q))
909 				list_del_init(sata_q.next);
910 		}
911 	} while (eh_dev);
912 }
913 
914 void sas_ata_schedule_reset(struct domain_device *dev)
915 {
916 	struct ata_eh_info *ehi;
917 	struct ata_port *ap;
918 	unsigned long flags;
919 
920 	if (!dev_is_sata(dev))
921 		return;
922 
923 	ap = dev->sata_dev.ap;
924 	ehi = &ap->link.eh_info;
925 
926 	spin_lock_irqsave(ap->lock, flags);
927 	ehi->err_mask |= AC_ERR_TIMEOUT;
928 	ehi->action |= ATA_EH_RESET;
929 	ata_port_schedule_eh(ap);
930 	spin_unlock_irqrestore(ap->lock, flags);
931 }
932 EXPORT_SYMBOL_GPL(sas_ata_schedule_reset);
933 
934 void sas_ata_wait_eh(struct domain_device *dev)
935 {
936 	struct ata_port *ap;
937 
938 	if (!dev_is_sata(dev))
939 		return;
940 
941 	ap = dev->sata_dev.ap;
942 	ata_port_wait_eh(ap);
943 }
944 
945 void sas_ata_device_link_abort(struct domain_device *device, bool force_reset)
946 {
947 	struct ata_port *ap = device->sata_dev.ap;
948 	struct ata_link *link = &ap->link;
949 	unsigned long flags;
950 
951 	spin_lock_irqsave(ap->lock, flags);
952 	device->sata_dev.fis[2] = ATA_ERR | ATA_DRDY; /* tf status */
953 	device->sata_dev.fis[3] = ATA_ABORTED; /* tf error */
954 
955 	link->eh_info.err_mask |= AC_ERR_DEV;
956 	if (force_reset)
957 		link->eh_info.action |= ATA_EH_RESET;
958 	ata_link_abort(link);
959 	spin_unlock_irqrestore(ap->lock, flags);
960 }
961 EXPORT_SYMBOL_GPL(sas_ata_device_link_abort);
962 
963 int sas_execute_ata_cmd(struct domain_device *device, u8 *fis, int force_phy_id)
964 {
965 	struct sas_tmf_task tmf_task = {};
966 	return sas_execute_tmf(device, fis, sizeof(struct host_to_dev_fis),
967 			       force_phy_id, &tmf_task);
968 }
969 EXPORT_SYMBOL_GPL(sas_execute_ata_cmd);
970