xref: /openbmc/linux/drivers/scsi/libsas/sas_ata.c (revision fcbd8037)
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 
41 		case SAS_INTERRUPTED:
42 		case SAS_PHY_DOWN:
43 		case SAS_NAK_R_ERR:
44 			return AC_ERR_ATA_BUS;
45 
46 
47 		case SAS_DATA_UNDERRUN:
48 			/*
49 			 * Some programs that use the taskfile interface
50 			 * (smartctl in particular) can cause underrun
51 			 * problems.  Ignore these errors, perhaps at our
52 			 * peril.
53 			 */
54 			return 0;
55 
56 		case SAS_DATA_OVERRUN:
57 		case SAS_QUEUE_FULL:
58 		case SAS_DEVICE_UNKNOWN:
59 		case SAS_SG_ERR:
60 			return AC_ERR_INVALID;
61 
62 		case SAS_OPEN_TO:
63 		case SAS_OPEN_REJECT:
64 			pr_warn("%s: Saw error %d.  What to do?\n",
65 				__func__, ts->stat);
66 			return AC_ERR_OTHER;
67 
68 		case SAM_STAT_CHECK_CONDITION:
69 		case SAS_ABORTED_TASK:
70 			return AC_ERR_DEV;
71 
72 		case SAS_PROTO_RESPONSE:
73 			/* This means the ending_fis has the error
74 			 * value; return 0 here to collect it */
75 			return 0;
76 		default:
77 			return 0;
78 	}
79 }
80 
81 static void sas_ata_task_done(struct sas_task *task)
82 {
83 	struct ata_queued_cmd *qc = task->uldd_task;
84 	struct domain_device *dev = task->dev;
85 	struct task_status_struct *stat = &task->task_status;
86 	struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
87 	struct sas_ha_struct *sas_ha = dev->port->ha;
88 	enum ata_completion_errors ac;
89 	unsigned long flags;
90 	struct ata_link *link;
91 	struct ata_port *ap;
92 
93 	spin_lock_irqsave(&dev->done_lock, flags);
94 	if (test_bit(SAS_HA_FROZEN, &sas_ha->state))
95 		task = NULL;
96 	else if (qc && qc->scsicmd)
97 		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
98 	spin_unlock_irqrestore(&dev->done_lock, flags);
99 
100 	/* check if libsas-eh got to the task before us */
101 	if (unlikely(!task))
102 		return;
103 
104 	if (!qc)
105 		goto qc_already_gone;
106 
107 	ap = qc->ap;
108 	link = &ap->link;
109 
110 	spin_lock_irqsave(ap->lock, flags);
111 	/* check if we lost the race with libata/sas_ata_post_internal() */
112 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN)) {
113 		spin_unlock_irqrestore(ap->lock, flags);
114 		if (qc->scsicmd)
115 			goto qc_already_gone;
116 		else {
117 			/* if eh is not involved and the port is frozen then the
118 			 * ata internal abort process has taken responsibility
119 			 * for this sas_task
120 			 */
121 			return;
122 		}
123 	}
124 
125 	if (stat->stat == SAS_PROTO_RESPONSE || stat->stat == SAM_STAT_GOOD ||
126 	    ((stat->stat == SAM_STAT_CHECK_CONDITION &&
127 	      dev->sata_dev.class == ATA_DEV_ATAPI))) {
128 		memcpy(dev->sata_dev.fis, resp->ending_fis, ATA_RESP_FIS_SIZE);
129 
130 		if (!link->sactive) {
131 			qc->err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
132 		} else {
133 			link->eh_info.err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
134 			if (unlikely(link->eh_info.err_mask))
135 				qc->flags |= ATA_QCFLAG_FAILED;
136 		}
137 	} else {
138 		ac = sas_to_ata_err(stat);
139 		if (ac) {
140 			pr_warn("%s: SAS error %x\n", __func__, stat->stat);
141 			/* We saw a SAS error. Send a vague error. */
142 			if (!link->sactive) {
143 				qc->err_mask = ac;
144 			} else {
145 				link->eh_info.err_mask |= AC_ERR_DEV;
146 				qc->flags |= ATA_QCFLAG_FAILED;
147 			}
148 
149 			dev->sata_dev.fis[3] = 0x04; /* status err */
150 			dev->sata_dev.fis[2] = ATA_ERR;
151 		}
152 	}
153 
154 	qc->lldd_task = NULL;
155 	ata_qc_complete(qc);
156 	spin_unlock_irqrestore(ap->lock, flags);
157 
158 qc_already_gone:
159 	sas_free_task(task);
160 }
161 
162 static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
163 {
164 	struct sas_task *task;
165 	struct scatterlist *sg;
166 	int ret = AC_ERR_SYSTEM;
167 	unsigned int si, xfer = 0;
168 	struct ata_port *ap = qc->ap;
169 	struct domain_device *dev = ap->private_data;
170 	struct sas_ha_struct *sas_ha = dev->port->ha;
171 	struct Scsi_Host *host = sas_ha->core.shost;
172 	struct sas_internal *i = to_sas_internal(host->transportt);
173 
174 	/* TODO: we should try to remove that unlock */
175 	spin_unlock(ap->lock);
176 
177 	/* If the device fell off, no sense in issuing commands */
178 	if (test_bit(SAS_DEV_GONE, &dev->state))
179 		goto out;
180 
181 	task = sas_alloc_task(GFP_ATOMIC);
182 	if (!task)
183 		goto out;
184 	task->dev = dev;
185 	task->task_proto = SAS_PROTOCOL_STP;
186 	task->task_done = sas_ata_task_done;
187 
188 	if (qc->tf.command == ATA_CMD_FPDMA_WRITE ||
189 	    qc->tf.command == ATA_CMD_FPDMA_READ ||
190 	    qc->tf.command == ATA_CMD_FPDMA_RECV ||
191 	    qc->tf.command == ATA_CMD_FPDMA_SEND ||
192 	    qc->tf.command == ATA_CMD_NCQ_NON_DATA) {
193 		/* Need to zero out the tag libata assigned us */
194 		qc->tf.nsect = 0;
195 	}
196 
197 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, (u8 *)&task->ata_task.fis);
198 	task->uldd_task = qc;
199 	if (ata_is_atapi(qc->tf.protocol)) {
200 		memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
201 		task->total_xfer_len = qc->nbytes;
202 		task->num_scatter = qc->n_elem;
203 	} else {
204 		for_each_sg(qc->sg, sg, qc->n_elem, si)
205 			xfer += sg_dma_len(sg);
206 
207 		task->total_xfer_len = xfer;
208 		task->num_scatter = si;
209 	}
210 
211 	task->data_dir = qc->dma_dir;
212 	task->scatter = qc->sg;
213 	task->ata_task.retry_count = 1;
214 	task->task_state_flags = SAS_TASK_STATE_PENDING;
215 	qc->lldd_task = task;
216 
217 	task->ata_task.use_ncq = ata_is_ncq(qc->tf.protocol);
218 	task->ata_task.dma_xfer = ata_is_dma(qc->tf.protocol);
219 
220 	if (qc->scsicmd)
221 		ASSIGN_SAS_TASK(qc->scsicmd, task);
222 
223 	ret = i->dft->lldd_execute_task(task, GFP_ATOMIC);
224 	if (ret) {
225 		pr_debug("lldd_execute_task returned: %d\n", ret);
226 
227 		if (qc->scsicmd)
228 			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
229 		sas_free_task(task);
230 		qc->lldd_task = NULL;
231 		ret = AC_ERR_SYSTEM;
232 	}
233 
234  out:
235 	spin_lock(ap->lock);
236 	return ret;
237 }
238 
239 static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
240 {
241 	struct domain_device *dev = qc->ap->private_data;
242 
243 	ata_tf_from_fis(dev->sata_dev.fis, &qc->result_tf);
244 	return true;
245 }
246 
247 static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
248 {
249 	return to_sas_internal(dev->port->ha->core.shost->transportt);
250 }
251 
252 static int sas_get_ata_command_set(struct domain_device *dev);
253 
254 int sas_get_ata_info(struct domain_device *dev, struct ex_phy *phy)
255 {
256 	if (phy->attached_tproto & SAS_PROTOCOL_STP)
257 		dev->tproto = phy->attached_tproto;
258 	if (phy->attached_sata_dev)
259 		dev->tproto |= SAS_SATA_DEV;
260 
261 	if (phy->attached_dev_type == SAS_SATA_PENDING)
262 		dev->dev_type = SAS_SATA_PENDING;
263 	else {
264 		int res;
265 
266 		dev->dev_type = SAS_SATA_DEV;
267 		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
268 					      &dev->sata_dev.rps_resp);
269 		if (res) {
270 			pr_debug("report phy sata to %016llx:%02d returned 0x%x\n",
271 				 SAS_ADDR(dev->parent->sas_addr),
272 				 phy->phy_id, res);
273 			return res;
274 		}
275 		memcpy(dev->frame_rcvd, &dev->sata_dev.rps_resp.rps.fis,
276 		       sizeof(struct dev_to_host_fis));
277 		dev->sata_dev.class = sas_get_ata_command_set(dev);
278 	}
279 	return 0;
280 }
281 
282 static int sas_ata_clear_pending(struct domain_device *dev, struct ex_phy *phy)
283 {
284 	int res;
285 
286 	/* we weren't pending, so successfully end the reset sequence now */
287 	if (dev->dev_type != SAS_SATA_PENDING)
288 		return 1;
289 
290 	/* hmmm, if this succeeds do we need to repost the domain_device to the
291 	 * lldd so it can pick up new parameters?
292 	 */
293 	res = sas_get_ata_info(dev, phy);
294 	if (res)
295 		return 0; /* retry */
296 	else
297 		return 1;
298 }
299 
300 static int smp_ata_check_ready(struct ata_link *link)
301 {
302 	int res;
303 	struct ata_port *ap = link->ap;
304 	struct domain_device *dev = ap->private_data;
305 	struct domain_device *ex_dev = dev->parent;
306 	struct sas_phy *phy = sas_get_local_phy(dev);
307 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy->number];
308 
309 	res = sas_ex_phy_discover(ex_dev, phy->number);
310 	sas_put_local_phy(phy);
311 
312 	/* break the wait early if the expander is unreachable,
313 	 * otherwise keep polling
314 	 */
315 	if (res == -ECOMM)
316 		return res;
317 	if (res != SMP_RESP_FUNC_ACC)
318 		return 0;
319 
320 	switch (ex_phy->attached_dev_type) {
321 	case SAS_SATA_PENDING:
322 		return 0;
323 	case SAS_END_DEVICE:
324 		if (ex_phy->attached_sata_dev)
325 			return sas_ata_clear_pending(dev, ex_phy);
326 		/* fall through */
327 	default:
328 		return -ENODEV;
329 	}
330 }
331 
332 static int local_ata_check_ready(struct ata_link *link)
333 {
334 	struct ata_port *ap = link->ap;
335 	struct domain_device *dev = ap->private_data;
336 	struct sas_internal *i = dev_to_sas_internal(dev);
337 
338 	if (i->dft->lldd_ata_check_ready)
339 		return i->dft->lldd_ata_check_ready(dev);
340 	else {
341 		/* lldd's that don't implement 'ready' checking get the
342 		 * old default behavior of not coordinating reset
343 		 * recovery with libata
344 		 */
345 		return 1;
346 	}
347 }
348 
349 static int sas_ata_printk(const char *level, const struct domain_device *ddev,
350 			  const char *fmt, ...)
351 {
352 	struct ata_port *ap = ddev->sata_dev.ap;
353 	struct device *dev = &ddev->rphy->dev;
354 	struct va_format vaf;
355 	va_list args;
356 	int r;
357 
358 	va_start(args, fmt);
359 
360 	vaf.fmt = fmt;
361 	vaf.va = &args;
362 
363 	r = printk("%s" SAS_FMT "ata%u: %s: %pV",
364 		   level, ap->print_id, dev_name(dev), &vaf);
365 
366 	va_end(args);
367 
368 	return r;
369 }
370 
371 static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
372 			      unsigned long deadline)
373 {
374 	int ret = 0, res;
375 	struct sas_phy *phy;
376 	struct ata_port *ap = link->ap;
377 	int (*check_ready)(struct ata_link *link);
378 	struct domain_device *dev = ap->private_data;
379 	struct sas_internal *i = dev_to_sas_internal(dev);
380 
381 	res = i->dft->lldd_I_T_nexus_reset(dev);
382 	if (res == -ENODEV)
383 		return res;
384 
385 	if (res != TMF_RESP_FUNC_COMPLETE)
386 		sas_ata_printk(KERN_DEBUG, dev, "Unable to reset ata device?\n");
387 
388 	phy = sas_get_local_phy(dev);
389 	if (scsi_is_sas_phy_local(phy))
390 		check_ready = local_ata_check_ready;
391 	else
392 		check_ready = smp_ata_check_ready;
393 	sas_put_local_phy(phy);
394 
395 	ret = ata_wait_after_reset(link, deadline, check_ready);
396 	if (ret && ret != -EAGAIN)
397 		sas_ata_printk(KERN_ERR, dev, "reset failed (errno=%d)\n", ret);
398 
399 	*class = dev->sata_dev.class;
400 
401 	ap->cbl = ATA_CBL_SATA;
402 	return ret;
403 }
404 
405 /*
406  * notify the lldd to forget the sas_task for this internal ata command
407  * that bypasses scsi-eh
408  */
409 static void sas_ata_internal_abort(struct sas_task *task)
410 {
411 	struct sas_internal *si = dev_to_sas_internal(task->dev);
412 	unsigned long flags;
413 	int res;
414 
415 	spin_lock_irqsave(&task->task_state_lock, flags);
416 	if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
417 	    task->task_state_flags & SAS_TASK_STATE_DONE) {
418 		spin_unlock_irqrestore(&task->task_state_lock, flags);
419 		pr_debug("%s: Task %p already finished.\n", __func__, task);
420 		goto out;
421 	}
422 	task->task_state_flags |= SAS_TASK_STATE_ABORTED;
423 	spin_unlock_irqrestore(&task->task_state_lock, flags);
424 
425 	res = si->dft->lldd_abort_task(task);
426 
427 	spin_lock_irqsave(&task->task_state_lock, flags);
428 	if (task->task_state_flags & SAS_TASK_STATE_DONE ||
429 	    res == TMF_RESP_FUNC_COMPLETE) {
430 		spin_unlock_irqrestore(&task->task_state_lock, flags);
431 		goto out;
432 	}
433 
434 	/* XXX we are not prepared to deal with ->lldd_abort_task()
435 	 * failures.  TODO: lldds need to unconditionally forget about
436 	 * aborted ata tasks, otherwise we (likely) leak the sas task
437 	 * here
438 	 */
439 	pr_warn("%s: Task %p leaked.\n", __func__, task);
440 
441 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
442 		task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
443 	spin_unlock_irqrestore(&task->task_state_lock, flags);
444 
445 	return;
446  out:
447 	sas_free_task(task);
448 }
449 
450 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
451 {
452 	if (qc->flags & ATA_QCFLAG_FAILED)
453 		qc->err_mask |= AC_ERR_OTHER;
454 
455 	if (qc->err_mask) {
456 		/*
457 		 * Find the sas_task and kill it.  By this point, libata
458 		 * has decided to kill the qc and has frozen the port.
459 		 * In this state sas_ata_task_done() will no longer free
460 		 * the sas_task, so we need to notify the lldd (via
461 		 * ->lldd_abort_task) that the task is dead and free it
462 		 *  ourselves.
463 		 */
464 		struct sas_task *task = qc->lldd_task;
465 
466 		qc->lldd_task = NULL;
467 		if (!task)
468 			return;
469 		task->uldd_task = NULL;
470 		sas_ata_internal_abort(task);
471 	}
472 }
473 
474 
475 static void sas_ata_set_dmamode(struct ata_port *ap, struct ata_device *ata_dev)
476 {
477 	struct domain_device *dev = ap->private_data;
478 	struct sas_internal *i = dev_to_sas_internal(dev);
479 
480 	if (i->dft->lldd_ata_set_dmamode)
481 		i->dft->lldd_ata_set_dmamode(dev);
482 }
483 
484 static void sas_ata_sched_eh(struct ata_port *ap)
485 {
486 	struct domain_device *dev = ap->private_data;
487 	struct sas_ha_struct *ha = dev->port->ha;
488 	unsigned long flags;
489 
490 	spin_lock_irqsave(&ha->lock, flags);
491 	if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
492 		ha->eh_active++;
493 	ata_std_sched_eh(ap);
494 	spin_unlock_irqrestore(&ha->lock, flags);
495 }
496 
497 void sas_ata_end_eh(struct ata_port *ap)
498 {
499 	struct domain_device *dev = ap->private_data;
500 	struct sas_ha_struct *ha = dev->port->ha;
501 	unsigned long flags;
502 
503 	spin_lock_irqsave(&ha->lock, flags);
504 	if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
505 		ha->eh_active--;
506 	spin_unlock_irqrestore(&ha->lock, flags);
507 }
508 
509 static struct ata_port_operations sas_sata_ops = {
510 	.prereset		= ata_std_prereset,
511 	.hardreset		= sas_ata_hard_reset,
512 	.postreset		= ata_std_postreset,
513 	.error_handler		= ata_std_error_handler,
514 	.post_internal_cmd	= sas_ata_post_internal,
515 	.qc_defer               = ata_std_qc_defer,
516 	.qc_prep		= ata_noop_qc_prep,
517 	.qc_issue		= sas_ata_qc_issue,
518 	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
519 	.port_start		= ata_sas_port_start,
520 	.port_stop		= ata_sas_port_stop,
521 	.set_dmamode		= sas_ata_set_dmamode,
522 	.sched_eh		= sas_ata_sched_eh,
523 	.end_eh			= sas_ata_end_eh,
524 };
525 
526 static struct ata_port_info sata_port_info = {
527 	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
528 		 ATA_FLAG_SAS_HOST | ATA_FLAG_FPDMA_AUX,
529 	.pio_mask = ATA_PIO4,
530 	.mwdma_mask = ATA_MWDMA2,
531 	.udma_mask = ATA_UDMA6,
532 	.port_ops = &sas_sata_ops
533 };
534 
535 int sas_ata_init(struct domain_device *found_dev)
536 {
537 	struct sas_ha_struct *ha = found_dev->port->ha;
538 	struct Scsi_Host *shost = ha->core.shost;
539 	struct ata_host *ata_host;
540 	struct ata_port *ap;
541 	int rc;
542 
543 	ata_host = kzalloc(sizeof(*ata_host), GFP_KERNEL);
544 	if (!ata_host)	{
545 		pr_err("ata host alloc failed.\n");
546 		return -ENOMEM;
547 	}
548 
549 	ata_host_init(ata_host, ha->dev, &sas_sata_ops);
550 
551 	ap = ata_sas_port_alloc(ata_host, &sata_port_info, shost);
552 	if (!ap) {
553 		pr_err("ata_sas_port_alloc failed.\n");
554 		rc = -ENODEV;
555 		goto free_host;
556 	}
557 
558 	ap->private_data = found_dev;
559 	ap->cbl = ATA_CBL_SATA;
560 	ap->scsi_host = shost;
561 	rc = ata_sas_port_init(ap);
562 	if (rc)
563 		goto destroy_port;
564 
565 	rc = ata_sas_tport_add(ata_host->dev, ap);
566 	if (rc)
567 		goto destroy_port;
568 
569 	found_dev->sata_dev.ata_host = ata_host;
570 	found_dev->sata_dev.ap = ap;
571 
572 	return 0;
573 
574 destroy_port:
575 	ata_sas_port_destroy(ap);
576 free_host:
577 	ata_host_put(ata_host);
578 	return rc;
579 }
580 
581 void sas_ata_task_abort(struct sas_task *task)
582 {
583 	struct ata_queued_cmd *qc = task->uldd_task;
584 	struct completion *waiting;
585 
586 	/* Bounce SCSI-initiated commands to the SCSI EH */
587 	if (qc->scsicmd) {
588 		blk_abort_request(qc->scsicmd->request);
589 		return;
590 	}
591 
592 	/* Internal command, fake a timeout and complete. */
593 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
594 	qc->flags |= ATA_QCFLAG_FAILED;
595 	qc->err_mask |= AC_ERR_TIMEOUT;
596 	waiting = qc->private_data;
597 	complete(waiting);
598 }
599 
600 static int sas_get_ata_command_set(struct domain_device *dev)
601 {
602 	struct dev_to_host_fis *fis =
603 		(struct dev_to_host_fis *) dev->frame_rcvd;
604 	struct ata_taskfile tf;
605 
606 	if (dev->dev_type == SAS_SATA_PENDING)
607 		return ATA_DEV_UNKNOWN;
608 
609 	ata_tf_from_fis((const u8 *)fis, &tf);
610 
611 	return ata_dev_classify(&tf);
612 }
613 
614 void sas_probe_sata(struct asd_sas_port *port)
615 {
616 	struct domain_device *dev, *n;
617 
618 	mutex_lock(&port->ha->disco_mutex);
619 	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
620 		if (!dev_is_sata(dev))
621 			continue;
622 
623 		ata_sas_async_probe(dev->sata_dev.ap);
624 	}
625 	mutex_unlock(&port->ha->disco_mutex);
626 
627 	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
628 		if (!dev_is_sata(dev))
629 			continue;
630 
631 		sas_ata_wait_eh(dev);
632 
633 		/* if libata could not bring the link up, don't surface
634 		 * the device
635 		 */
636 		if (!ata_dev_enabled(sas_to_ata_dev(dev)))
637 			sas_fail_probe(dev, __func__, -ENODEV);
638 	}
639 
640 }
641 
642 static void sas_ata_flush_pm_eh(struct asd_sas_port *port, const char *func)
643 {
644 	struct domain_device *dev, *n;
645 
646 	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
647 		if (!dev_is_sata(dev))
648 			continue;
649 
650 		sas_ata_wait_eh(dev);
651 
652 		/* if libata failed to power manage the device, tear it down */
653 		if (ata_dev_disabled(sas_to_ata_dev(dev)))
654 			sas_fail_probe(dev, func, -ENODEV);
655 	}
656 }
657 
658 void sas_suspend_sata(struct asd_sas_port *port)
659 {
660 	struct domain_device *dev;
661 
662 	mutex_lock(&port->ha->disco_mutex);
663 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
664 		struct sata_device *sata;
665 
666 		if (!dev_is_sata(dev))
667 			continue;
668 
669 		sata = &dev->sata_dev;
670 		if (sata->ap->pm_mesg.event == PM_EVENT_SUSPEND)
671 			continue;
672 
673 		ata_sas_port_suspend(sata->ap);
674 	}
675 	mutex_unlock(&port->ha->disco_mutex);
676 
677 	sas_ata_flush_pm_eh(port, __func__);
678 }
679 
680 void sas_resume_sata(struct asd_sas_port *port)
681 {
682 	struct domain_device *dev;
683 
684 	mutex_lock(&port->ha->disco_mutex);
685 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
686 		struct sata_device *sata;
687 
688 		if (!dev_is_sata(dev))
689 			continue;
690 
691 		sata = &dev->sata_dev;
692 		if (sata->ap->pm_mesg.event == PM_EVENT_ON)
693 			continue;
694 
695 		ata_sas_port_resume(sata->ap);
696 	}
697 	mutex_unlock(&port->ha->disco_mutex);
698 
699 	sas_ata_flush_pm_eh(port, __func__);
700 }
701 
702 /**
703  * sas_discover_sata - discover an STP/SATA domain device
704  * @dev: pointer to struct domain_device of interest
705  *
706  * Devices directly attached to a HA port, have no parents.  All other
707  * devices do, and should have their "parent" pointer set appropriately
708  * before calling this function.
709  */
710 int sas_discover_sata(struct domain_device *dev)
711 {
712 	int res;
713 
714 	if (dev->dev_type == SAS_SATA_PM)
715 		return -ENODEV;
716 
717 	dev->sata_dev.class = sas_get_ata_command_set(dev);
718 	sas_fill_in_rphy(dev, dev->rphy);
719 
720 	res = sas_notify_lldd_dev_found(dev);
721 	if (res)
722 		return res;
723 
724 	return 0;
725 }
726 
727 static void async_sas_ata_eh(void *data, async_cookie_t cookie)
728 {
729 	struct domain_device *dev = data;
730 	struct ata_port *ap = dev->sata_dev.ap;
731 	struct sas_ha_struct *ha = dev->port->ha;
732 
733 	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
734 	ata_scsi_port_error_handler(ha->core.shost, ap);
735 	sas_put_device(dev);
736 }
737 
738 void sas_ata_strategy_handler(struct Scsi_Host *shost)
739 {
740 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
741 	ASYNC_DOMAIN_EXCLUSIVE(async);
742 	int i;
743 
744 	/* it's ok to defer revalidation events during ata eh, these
745 	 * disks are in one of three states:
746 	 * 1/ present for initial domain discovery, and these
747 	 *    resets will cause bcn flutters
748 	 * 2/ hot removed, we'll discover that after eh fails
749 	 * 3/ hot added after initial discovery, lost the race, and need
750 	 *    to catch the next train.
751 	 */
752 	sas_disable_revalidation(sas_ha);
753 
754 	spin_lock_irq(&sas_ha->phy_port_lock);
755 	for (i = 0; i < sas_ha->num_phys; i++) {
756 		struct asd_sas_port *port = sas_ha->sas_port[i];
757 		struct domain_device *dev;
758 
759 		spin_lock(&port->dev_list_lock);
760 		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
761 			if (!dev_is_sata(dev))
762 				continue;
763 
764 			/* hold a reference over eh since we may be
765 			 * racing with final remove once all commands
766 			 * are completed
767 			 */
768 			kref_get(&dev->kref);
769 
770 			async_schedule_domain(async_sas_ata_eh, dev, &async);
771 		}
772 		spin_unlock(&port->dev_list_lock);
773 	}
774 	spin_unlock_irq(&sas_ha->phy_port_lock);
775 
776 	async_synchronize_full_domain(&async);
777 
778 	sas_enable_revalidation(sas_ha);
779 }
780 
781 void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
782 		struct list_head *done_q)
783 {
784 	struct scsi_cmnd *cmd, *n;
785 	struct domain_device *eh_dev;
786 
787 	do {
788 		LIST_HEAD(sata_q);
789 		eh_dev = NULL;
790 
791 		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
792 			struct domain_device *ddev = cmd_to_domain_dev(cmd);
793 
794 			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
795 				continue;
796 			if (eh_dev && eh_dev != ddev)
797 				continue;
798 			eh_dev = ddev;
799 			list_move(&cmd->eh_entry, &sata_q);
800 		}
801 
802 		if (!list_empty(&sata_q)) {
803 			struct ata_port *ap = eh_dev->sata_dev.ap;
804 
805 			sas_ata_printk(KERN_DEBUG, eh_dev, "cmd error handler\n");
806 			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
807 			/*
808 			 * ata's error handler may leave the cmd on the list
809 			 * so make sure they don't remain on a stack list
810 			 * about to go out of scope.
811 			 *
812 			 * This looks strange, since the commands are
813 			 * now part of no list, but the next error
814 			 * action will be ata_port_error_handler()
815 			 * which takes no list and sweeps them up
816 			 * anyway from the ata tag array.
817 			 */
818 			while (!list_empty(&sata_q))
819 				list_del_init(sata_q.next);
820 		}
821 	} while (eh_dev);
822 }
823 
824 void sas_ata_schedule_reset(struct domain_device *dev)
825 {
826 	struct ata_eh_info *ehi;
827 	struct ata_port *ap;
828 	unsigned long flags;
829 
830 	if (!dev_is_sata(dev))
831 		return;
832 
833 	ap = dev->sata_dev.ap;
834 	ehi = &ap->link.eh_info;
835 
836 	spin_lock_irqsave(ap->lock, flags);
837 	ehi->err_mask |= AC_ERR_TIMEOUT;
838 	ehi->action |= ATA_EH_RESET;
839 	ata_port_schedule_eh(ap);
840 	spin_unlock_irqrestore(ap->lock, flags);
841 }
842 EXPORT_SYMBOL_GPL(sas_ata_schedule_reset);
843 
844 void sas_ata_wait_eh(struct domain_device *dev)
845 {
846 	struct ata_port *ap;
847 
848 	if (!dev_is_sata(dev))
849 		return;
850 
851 	ap = dev->sata_dev.ap;
852 	ata_port_wait_eh(ap);
853 }
854