xref: /openbmc/linux/drivers/scsi/libsas/sas_ata.c (revision 979ac5ef)
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_FAILED;
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_FAILED;
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 bool 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 	return true;
235 }
236 
237 static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
238 {
239 	return to_sas_internal(dev->port->ha->core.shost->transportt);
240 }
241 
242 static int sas_get_ata_command_set(struct domain_device *dev);
243 
244 int sas_get_ata_info(struct domain_device *dev, struct ex_phy *phy)
245 {
246 	if (phy->attached_tproto & SAS_PROTOCOL_STP)
247 		dev->tproto = phy->attached_tproto;
248 	if (phy->attached_sata_dev)
249 		dev->tproto |= SAS_SATA_DEV;
250 
251 	if (phy->attached_dev_type == SAS_SATA_PENDING)
252 		dev->dev_type = SAS_SATA_PENDING;
253 	else {
254 		int res;
255 
256 		dev->dev_type = SAS_SATA_DEV;
257 		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
258 					      &dev->sata_dev.rps_resp);
259 		if (res) {
260 			pr_debug("report phy sata to %016llx:%02d returned 0x%x\n",
261 				 SAS_ADDR(dev->parent->sas_addr),
262 				 phy->phy_id, res);
263 			return res;
264 		}
265 		memcpy(dev->frame_rcvd, &dev->sata_dev.rps_resp.rps.fis,
266 		       sizeof(struct dev_to_host_fis));
267 		dev->sata_dev.class = sas_get_ata_command_set(dev);
268 	}
269 	return 0;
270 }
271 
272 static int sas_ata_clear_pending(struct domain_device *dev, struct ex_phy *phy)
273 {
274 	int res;
275 
276 	/* we weren't pending, so successfully end the reset sequence now */
277 	if (dev->dev_type != SAS_SATA_PENDING)
278 		return 1;
279 
280 	/* hmmm, if this succeeds do we need to repost the domain_device to the
281 	 * lldd so it can pick up new parameters?
282 	 */
283 	res = sas_get_ata_info(dev, phy);
284 	if (res)
285 		return 0; /* retry */
286 	else
287 		return 1;
288 }
289 
290 int smp_ata_check_ready_type(struct ata_link *link)
291 {
292 	struct domain_device *dev = link->ap->private_data;
293 	struct sas_phy *phy = sas_get_local_phy(dev);
294 	struct domain_device *ex_dev = dev->parent;
295 	enum sas_device_type type = SAS_PHY_UNUSED;
296 	u8 sas_addr[SAS_ADDR_SIZE];
297 	int res;
298 
299 	res = sas_get_phy_attached_dev(ex_dev, phy->number, sas_addr, &type);
300 	sas_put_local_phy(phy);
301 	if (res)
302 		return res;
303 
304 	switch (type) {
305 	case SAS_SATA_PENDING:
306 		return 0;
307 	case SAS_END_DEVICE:
308 		return 1;
309 	default:
310 		return -ENODEV;
311 	}
312 }
313 EXPORT_SYMBOL_GPL(smp_ata_check_ready_type);
314 
315 static int smp_ata_check_ready(struct ata_link *link)
316 {
317 	int res;
318 	struct ata_port *ap = link->ap;
319 	struct domain_device *dev = ap->private_data;
320 	struct domain_device *ex_dev = dev->parent;
321 	struct sas_phy *phy = sas_get_local_phy(dev);
322 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy->number];
323 
324 	res = sas_ex_phy_discover(ex_dev, phy->number);
325 	sas_put_local_phy(phy);
326 
327 	/* break the wait early if the expander is unreachable,
328 	 * otherwise keep polling
329 	 */
330 	if (res == -ECOMM)
331 		return res;
332 	if (res != SMP_RESP_FUNC_ACC)
333 		return 0;
334 
335 	switch (ex_phy->attached_dev_type) {
336 	case SAS_SATA_PENDING:
337 		return 0;
338 	case SAS_END_DEVICE:
339 		if (ex_phy->attached_sata_dev)
340 			return sas_ata_clear_pending(dev, ex_phy);
341 		fallthrough;
342 	default:
343 		return -ENODEV;
344 	}
345 }
346 
347 static int local_ata_check_ready(struct ata_link *link)
348 {
349 	struct ata_port *ap = link->ap;
350 	struct domain_device *dev = ap->private_data;
351 	struct sas_internal *i = dev_to_sas_internal(dev);
352 
353 	if (i->dft->lldd_ata_check_ready)
354 		return i->dft->lldd_ata_check_ready(dev);
355 	else {
356 		/* lldd's that don't implement 'ready' checking get the
357 		 * old default behavior of not coordinating reset
358 		 * recovery with libata
359 		 */
360 		return 1;
361 	}
362 }
363 
364 static int sas_ata_printk(const char *level, const struct domain_device *ddev,
365 			  const char *fmt, ...)
366 {
367 	struct ata_port *ap = ddev->sata_dev.ap;
368 	struct device *dev = &ddev->rphy->dev;
369 	struct va_format vaf;
370 	va_list args;
371 	int r;
372 
373 	va_start(args, fmt);
374 
375 	vaf.fmt = fmt;
376 	vaf.va = &args;
377 
378 	r = printk("%s" SAS_FMT "ata%u: %s: %pV",
379 		   level, ap->print_id, dev_name(dev), &vaf);
380 
381 	va_end(args);
382 
383 	return r;
384 }
385 
386 static int sas_ata_wait_after_reset(struct domain_device *dev, unsigned long deadline)
387 {
388 	struct sata_device *sata_dev = &dev->sata_dev;
389 	int (*check_ready)(struct ata_link *link);
390 	struct ata_port *ap = sata_dev->ap;
391 	struct ata_link *link = &ap->link;
392 	struct sas_phy *phy;
393 	int ret;
394 
395 	phy = sas_get_local_phy(dev);
396 	if (scsi_is_sas_phy_local(phy))
397 		check_ready = local_ata_check_ready;
398 	else
399 		check_ready = smp_ata_check_ready;
400 	sas_put_local_phy(phy);
401 
402 	ret = ata_wait_after_reset(link, deadline, check_ready);
403 	if (ret && ret != -EAGAIN)
404 		sas_ata_printk(KERN_ERR, dev, "reset failed (errno=%d)\n", ret);
405 
406 	return ret;
407 }
408 
409 static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
410 			      unsigned long deadline)
411 {
412 	struct ata_port *ap = link->ap;
413 	struct domain_device *dev = ap->private_data;
414 	struct sas_internal *i = dev_to_sas_internal(dev);
415 	int ret;
416 
417 	ret = i->dft->lldd_I_T_nexus_reset(dev);
418 	if (ret == -ENODEV)
419 		return ret;
420 
421 	if (ret != TMF_RESP_FUNC_COMPLETE)
422 		sas_ata_printk(KERN_DEBUG, dev, "Unable to reset ata device?\n");
423 
424 	ret = sas_ata_wait_after_reset(dev, deadline);
425 
426 	*class = dev->sata_dev.class;
427 
428 	ap->cbl = ATA_CBL_SATA;
429 	return ret;
430 }
431 
432 /*
433  * notify the lldd to forget the sas_task for this internal ata command
434  * that bypasses scsi-eh
435  */
436 static void sas_ata_internal_abort(struct sas_task *task)
437 {
438 	struct sas_internal *si = dev_to_sas_internal(task->dev);
439 	unsigned long flags;
440 	int res;
441 
442 	spin_lock_irqsave(&task->task_state_lock, flags);
443 	if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
444 	    task->task_state_flags & SAS_TASK_STATE_DONE) {
445 		spin_unlock_irqrestore(&task->task_state_lock, flags);
446 		pr_debug("%s: Task %p already finished.\n", __func__, task);
447 		goto out;
448 	}
449 	task->task_state_flags |= SAS_TASK_STATE_ABORTED;
450 	spin_unlock_irqrestore(&task->task_state_lock, flags);
451 
452 	res = si->dft->lldd_abort_task(task);
453 
454 	spin_lock_irqsave(&task->task_state_lock, flags);
455 	if (task->task_state_flags & SAS_TASK_STATE_DONE ||
456 	    res == TMF_RESP_FUNC_COMPLETE) {
457 		spin_unlock_irqrestore(&task->task_state_lock, flags);
458 		goto out;
459 	}
460 
461 	/* XXX we are not prepared to deal with ->lldd_abort_task()
462 	 * failures.  TODO: lldds need to unconditionally forget about
463 	 * aborted ata tasks, otherwise we (likely) leak the sas task
464 	 * here
465 	 */
466 	pr_warn("%s: Task %p leaked.\n", __func__, task);
467 
468 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
469 		task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
470 	spin_unlock_irqrestore(&task->task_state_lock, flags);
471 
472 	return;
473  out:
474 	sas_free_task(task);
475 }
476 
477 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
478 {
479 	if (qc->flags & ATA_QCFLAG_FAILED)
480 		qc->err_mask |= AC_ERR_OTHER;
481 
482 	if (qc->err_mask) {
483 		/*
484 		 * Find the sas_task and kill it.  By this point, libata
485 		 * has decided to kill the qc and has frozen the port.
486 		 * In this state sas_ata_task_done() will no longer free
487 		 * the sas_task, so we need to notify the lldd (via
488 		 * ->lldd_abort_task) that the task is dead and free it
489 		 *  ourselves.
490 		 */
491 		struct sas_task *task = qc->lldd_task;
492 
493 		qc->lldd_task = NULL;
494 		if (!task)
495 			return;
496 		task->uldd_task = NULL;
497 		sas_ata_internal_abort(task);
498 	}
499 }
500 
501 
502 static void sas_ata_set_dmamode(struct ata_port *ap, struct ata_device *ata_dev)
503 {
504 	struct domain_device *dev = ap->private_data;
505 	struct sas_internal *i = dev_to_sas_internal(dev);
506 
507 	if (i->dft->lldd_ata_set_dmamode)
508 		i->dft->lldd_ata_set_dmamode(dev);
509 }
510 
511 static void sas_ata_sched_eh(struct ata_port *ap)
512 {
513 	struct domain_device *dev = ap->private_data;
514 	struct sas_ha_struct *ha = dev->port->ha;
515 	unsigned long flags;
516 
517 	spin_lock_irqsave(&ha->lock, flags);
518 	if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
519 		ha->eh_active++;
520 	ata_std_sched_eh(ap);
521 	spin_unlock_irqrestore(&ha->lock, flags);
522 }
523 
524 void sas_ata_end_eh(struct ata_port *ap)
525 {
526 	struct domain_device *dev = ap->private_data;
527 	struct sas_ha_struct *ha = dev->port->ha;
528 	unsigned long flags;
529 
530 	spin_lock_irqsave(&ha->lock, flags);
531 	if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
532 		ha->eh_active--;
533 	spin_unlock_irqrestore(&ha->lock, flags);
534 }
535 
536 static int sas_ata_prereset(struct ata_link *link, unsigned long deadline)
537 {
538 	struct ata_port *ap = link->ap;
539 	struct domain_device *dev = ap->private_data;
540 	struct sas_phy *local_phy = sas_get_local_phy(dev);
541 	int res = 0;
542 
543 	if (!local_phy->enabled || test_bit(SAS_DEV_GONE, &dev->state))
544 		res = -ENOENT;
545 	sas_put_local_phy(local_phy);
546 
547 	return res;
548 }
549 
550 static struct ata_port_operations sas_sata_ops = {
551 	.prereset		= sas_ata_prereset,
552 	.hardreset		= sas_ata_hard_reset,
553 	.error_handler		= ata_std_error_handler,
554 	.post_internal_cmd	= sas_ata_post_internal,
555 	.qc_defer               = ata_std_qc_defer,
556 	.qc_prep		= ata_noop_qc_prep,
557 	.qc_issue		= sas_ata_qc_issue,
558 	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
559 	.port_start		= ata_sas_port_start,
560 	.port_stop		= ata_sas_port_stop,
561 	.set_dmamode		= sas_ata_set_dmamode,
562 	.sched_eh		= sas_ata_sched_eh,
563 	.end_eh			= sas_ata_end_eh,
564 };
565 
566 static struct ata_port_info sata_port_info = {
567 	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
568 		 ATA_FLAG_SAS_HOST | ATA_FLAG_FPDMA_AUX,
569 	.pio_mask = ATA_PIO4,
570 	.mwdma_mask = ATA_MWDMA2,
571 	.udma_mask = ATA_UDMA6,
572 	.port_ops = &sas_sata_ops
573 };
574 
575 int sas_ata_init(struct domain_device *found_dev)
576 {
577 	struct sas_ha_struct *ha = found_dev->port->ha;
578 	struct Scsi_Host *shost = ha->core.shost;
579 	struct ata_host *ata_host;
580 	struct ata_port *ap;
581 	int rc;
582 
583 	ata_host = kzalloc(sizeof(*ata_host), GFP_KERNEL);
584 	if (!ata_host)	{
585 		pr_err("ata host alloc failed.\n");
586 		return -ENOMEM;
587 	}
588 
589 	ata_host_init(ata_host, ha->dev, &sas_sata_ops);
590 
591 	ap = ata_sas_port_alloc(ata_host, &sata_port_info, shost);
592 	if (!ap) {
593 		pr_err("ata_sas_port_alloc failed.\n");
594 		rc = -ENODEV;
595 		goto free_host;
596 	}
597 
598 	ap->private_data = found_dev;
599 	ap->cbl = ATA_CBL_SATA;
600 	ap->scsi_host = shost;
601 	rc = ata_sas_port_init(ap);
602 	if (rc)
603 		goto destroy_port;
604 
605 	rc = ata_sas_tport_add(ata_host->dev, ap);
606 	if (rc)
607 		goto destroy_port;
608 
609 	found_dev->sata_dev.ata_host = ata_host;
610 	found_dev->sata_dev.ap = ap;
611 
612 	return 0;
613 
614 destroy_port:
615 	ata_sas_port_destroy(ap);
616 free_host:
617 	ata_host_put(ata_host);
618 	return rc;
619 }
620 
621 void sas_ata_task_abort(struct sas_task *task)
622 {
623 	struct ata_queued_cmd *qc = task->uldd_task;
624 	struct completion *waiting;
625 
626 	/* Bounce SCSI-initiated commands to the SCSI EH */
627 	if (qc->scsicmd) {
628 		blk_abort_request(scsi_cmd_to_rq(qc->scsicmd));
629 		return;
630 	}
631 
632 	/* Internal command, fake a timeout and complete. */
633 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
634 	qc->flags |= ATA_QCFLAG_FAILED;
635 	qc->err_mask |= AC_ERR_TIMEOUT;
636 	waiting = qc->private_data;
637 	complete(waiting);
638 }
639 
640 static int sas_get_ata_command_set(struct domain_device *dev)
641 {
642 	struct dev_to_host_fis *fis =
643 		(struct dev_to_host_fis *) dev->frame_rcvd;
644 	struct ata_taskfile tf;
645 
646 	if (dev->dev_type == SAS_SATA_PENDING)
647 		return ATA_DEV_UNKNOWN;
648 
649 	ata_tf_from_fis((const u8 *)fis, &tf);
650 
651 	return ata_dev_classify(&tf);
652 }
653 
654 void sas_probe_sata(struct asd_sas_port *port)
655 {
656 	struct domain_device *dev, *n;
657 
658 	mutex_lock(&port->ha->disco_mutex);
659 	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
660 		if (!dev_is_sata(dev))
661 			continue;
662 
663 		ata_sas_async_probe(dev->sata_dev.ap);
664 	}
665 	mutex_unlock(&port->ha->disco_mutex);
666 
667 	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
668 		if (!dev_is_sata(dev))
669 			continue;
670 
671 		sas_ata_wait_eh(dev);
672 
673 		/* if libata could not bring the link up, don't surface
674 		 * the device
675 		 */
676 		if (!ata_dev_enabled(sas_to_ata_dev(dev)))
677 			sas_fail_probe(dev, __func__, -ENODEV);
678 	}
679 
680 }
681 
682 static void sas_ata_flush_pm_eh(struct asd_sas_port *port, const char *func)
683 {
684 	struct domain_device *dev, *n;
685 
686 	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
687 		if (!dev_is_sata(dev))
688 			continue;
689 
690 		sas_ata_wait_eh(dev);
691 
692 		/* if libata failed to power manage the device, tear it down */
693 		if (ata_dev_disabled(sas_to_ata_dev(dev)))
694 			sas_fail_probe(dev, func, -ENODEV);
695 	}
696 }
697 
698 void sas_suspend_sata(struct asd_sas_port *port)
699 {
700 	struct domain_device *dev;
701 
702 	mutex_lock(&port->ha->disco_mutex);
703 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
704 		struct sata_device *sata;
705 
706 		if (!dev_is_sata(dev))
707 			continue;
708 
709 		sata = &dev->sata_dev;
710 		if (sata->ap->pm_mesg.event == PM_EVENT_SUSPEND)
711 			continue;
712 
713 		ata_sas_port_suspend(sata->ap);
714 	}
715 	mutex_unlock(&port->ha->disco_mutex);
716 
717 	sas_ata_flush_pm_eh(port, __func__);
718 }
719 
720 void sas_resume_sata(struct asd_sas_port *port)
721 {
722 	struct domain_device *dev;
723 
724 	mutex_lock(&port->ha->disco_mutex);
725 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
726 		struct sata_device *sata;
727 
728 		if (!dev_is_sata(dev))
729 			continue;
730 
731 		sata = &dev->sata_dev;
732 		if (sata->ap->pm_mesg.event == PM_EVENT_ON)
733 			continue;
734 
735 		ata_sas_port_resume(sata->ap);
736 	}
737 	mutex_unlock(&port->ha->disco_mutex);
738 
739 	sas_ata_flush_pm_eh(port, __func__);
740 }
741 
742 /**
743  * sas_discover_sata - discover an STP/SATA domain device
744  * @dev: pointer to struct domain_device of interest
745  *
746  * Devices directly attached to a HA port, have no parents.  All other
747  * devices do, and should have their "parent" pointer set appropriately
748  * before calling this function.
749  */
750 int sas_discover_sata(struct domain_device *dev)
751 {
752 	if (dev->dev_type == SAS_SATA_PM)
753 		return -ENODEV;
754 
755 	dev->sata_dev.class = sas_get_ata_command_set(dev);
756 	sas_fill_in_rphy(dev, dev->rphy);
757 
758 	return sas_notify_lldd_dev_found(dev);
759 }
760 
761 static void async_sas_ata_eh(void *data, async_cookie_t cookie)
762 {
763 	struct domain_device *dev = data;
764 	struct ata_port *ap = dev->sata_dev.ap;
765 	struct sas_ha_struct *ha = dev->port->ha;
766 
767 	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
768 	ata_scsi_port_error_handler(ha->core.shost, ap);
769 	sas_put_device(dev);
770 }
771 
772 void sas_ata_strategy_handler(struct Scsi_Host *shost)
773 {
774 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
775 	ASYNC_DOMAIN_EXCLUSIVE(async);
776 	int i;
777 
778 	/* it's ok to defer revalidation events during ata eh, these
779 	 * disks are in one of three states:
780 	 * 1/ present for initial domain discovery, and these
781 	 *    resets will cause bcn flutters
782 	 * 2/ hot removed, we'll discover that after eh fails
783 	 * 3/ hot added after initial discovery, lost the race, and need
784 	 *    to catch the next train.
785 	 */
786 	sas_disable_revalidation(sas_ha);
787 
788 	spin_lock_irq(&sas_ha->phy_port_lock);
789 	for (i = 0; i < sas_ha->num_phys; i++) {
790 		struct asd_sas_port *port = sas_ha->sas_port[i];
791 		struct domain_device *dev;
792 
793 		spin_lock(&port->dev_list_lock);
794 		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
795 			if (!dev_is_sata(dev))
796 				continue;
797 
798 			/* hold a reference over eh since we may be
799 			 * racing with final remove once all commands
800 			 * are completed
801 			 */
802 			kref_get(&dev->kref);
803 
804 			async_schedule_domain(async_sas_ata_eh, dev, &async);
805 		}
806 		spin_unlock(&port->dev_list_lock);
807 	}
808 	spin_unlock_irq(&sas_ha->phy_port_lock);
809 
810 	async_synchronize_full_domain(&async);
811 
812 	sas_enable_revalidation(sas_ha);
813 }
814 
815 void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q)
816 {
817 	struct scsi_cmnd *cmd, *n;
818 	struct domain_device *eh_dev;
819 
820 	do {
821 		LIST_HEAD(sata_q);
822 		eh_dev = NULL;
823 
824 		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
825 			struct domain_device *ddev = cmd_to_domain_dev(cmd);
826 
827 			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
828 				continue;
829 			if (eh_dev && eh_dev != ddev)
830 				continue;
831 			eh_dev = ddev;
832 			list_move(&cmd->eh_entry, &sata_q);
833 		}
834 
835 		if (!list_empty(&sata_q)) {
836 			struct ata_port *ap = eh_dev->sata_dev.ap;
837 
838 			sas_ata_printk(KERN_DEBUG, eh_dev, "cmd error handler\n");
839 			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
840 			/*
841 			 * ata's error handler may leave the cmd on the list
842 			 * so make sure they don't remain on a stack list
843 			 * about to go out of scope.
844 			 *
845 			 * This looks strange, since the commands are
846 			 * now part of no list, but the next error
847 			 * action will be ata_port_error_handler()
848 			 * which takes no list and sweeps them up
849 			 * anyway from the ata tag array.
850 			 */
851 			while (!list_empty(&sata_q))
852 				list_del_init(sata_q.next);
853 		}
854 	} while (eh_dev);
855 }
856 
857 void sas_ata_schedule_reset(struct domain_device *dev)
858 {
859 	struct ata_eh_info *ehi;
860 	struct ata_port *ap;
861 	unsigned long flags;
862 
863 	if (!dev_is_sata(dev))
864 		return;
865 
866 	ap = dev->sata_dev.ap;
867 	ehi = &ap->link.eh_info;
868 
869 	spin_lock_irqsave(ap->lock, flags);
870 	ehi->err_mask |= AC_ERR_TIMEOUT;
871 	ehi->action |= ATA_EH_RESET;
872 	ata_port_schedule_eh(ap);
873 	spin_unlock_irqrestore(ap->lock, flags);
874 }
875 EXPORT_SYMBOL_GPL(sas_ata_schedule_reset);
876 
877 void sas_ata_wait_eh(struct domain_device *dev)
878 {
879 	struct ata_port *ap;
880 
881 	if (!dev_is_sata(dev))
882 		return;
883 
884 	ap = dev->sata_dev.ap;
885 	ata_port_wait_eh(ap);
886 }
887 
888 void sas_ata_device_link_abort(struct domain_device *device, bool force_reset)
889 {
890 	struct ata_port *ap = device->sata_dev.ap;
891 	struct ata_link *link = &ap->link;
892 
893 	device->sata_dev.fis[2] = ATA_ERR | ATA_DRDY; /* tf status */
894 	device->sata_dev.fis[3] = ATA_ABORTED; /* tf error */
895 
896 	link->eh_info.err_mask |= AC_ERR_DEV;
897 	if (force_reset)
898 		link->eh_info.action |= ATA_EH_RESET;
899 	ata_link_abort(link);
900 }
901 EXPORT_SYMBOL_GPL(sas_ata_device_link_abort);
902 
903 int sas_execute_ata_cmd(struct domain_device *device, u8 *fis, int force_phy_id)
904 {
905 	struct sas_tmf_task tmf_task = {};
906 	return sas_execute_tmf(device, fis, sizeof(struct host_to_dev_fis),
907 			       force_phy_id, &tmf_task);
908 }
909 EXPORT_SYMBOL_GPL(sas_execute_ata_cmd);
910