xref: /openbmc/linux/drivers/scsi/libsas/sas_ata.c (revision c4f7ac64)
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_SG_ERR:
56 		return AC_ERR_INVALID;
57 	case SAS_OPEN_TO:
58 	case SAS_OPEN_REJECT:
59 		pr_warn("%s: Saw error %d.  What to do?\n",
60 			__func__, ts->stat);
61 		return AC_ERR_OTHER;
62 	case SAM_STAT_CHECK_CONDITION:
63 	case SAS_ABORTED_TASK:
64 		return AC_ERR_DEV;
65 	case SAS_PROTO_RESPONSE:
66 		/* This means the ending_fis has the error
67 		 * value; return 0 here to collect it
68 		 */
69 		return 0;
70 	default:
71 		return 0;
72 	}
73 }
74 
75 static void sas_ata_task_done(struct sas_task *task)
76 {
77 	struct ata_queued_cmd *qc = task->uldd_task;
78 	struct domain_device *dev = task->dev;
79 	struct task_status_struct *stat = &task->task_status;
80 	struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
81 	struct sas_ha_struct *sas_ha = dev->port->ha;
82 	enum ata_completion_errors ac;
83 	unsigned long flags;
84 	struct ata_link *link;
85 	struct ata_port *ap;
86 
87 	spin_lock_irqsave(&dev->done_lock, flags);
88 	if (test_bit(SAS_HA_FROZEN, &sas_ha->state))
89 		task = NULL;
90 	else if (qc && qc->scsicmd)
91 		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
92 	spin_unlock_irqrestore(&dev->done_lock, flags);
93 
94 	/* check if libsas-eh got to the task before us */
95 	if (unlikely(!task))
96 		return;
97 
98 	if (!qc)
99 		goto qc_already_gone;
100 
101 	ap = qc->ap;
102 	link = &ap->link;
103 
104 	spin_lock_irqsave(ap->lock, flags);
105 	/* check if we lost the race with libata/sas_ata_post_internal() */
106 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN)) {
107 		spin_unlock_irqrestore(ap->lock, flags);
108 		if (qc->scsicmd)
109 			goto qc_already_gone;
110 		else {
111 			/* if eh is not involved and the port is frozen then the
112 			 * ata internal abort process has taken responsibility
113 			 * for this sas_task
114 			 */
115 			return;
116 		}
117 	}
118 
119 	if (stat->stat == SAS_PROTO_RESPONSE || stat->stat == SAM_STAT_GOOD ||
120 	    ((stat->stat == SAM_STAT_CHECK_CONDITION &&
121 	      dev->sata_dev.class == ATA_DEV_ATAPI))) {
122 		memcpy(dev->sata_dev.fis, resp->ending_fis, ATA_RESP_FIS_SIZE);
123 
124 		if (!link->sactive) {
125 			qc->err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
126 		} else {
127 			link->eh_info.err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
128 			if (unlikely(link->eh_info.err_mask))
129 				qc->flags |= ATA_QCFLAG_FAILED;
130 		}
131 	} else {
132 		ac = sas_to_ata_err(stat);
133 		if (ac) {
134 			pr_warn("%s: SAS error 0x%x\n", __func__, stat->stat);
135 			/* We saw a SAS error. Send a vague error. */
136 			if (!link->sactive) {
137 				qc->err_mask = ac;
138 			} else {
139 				link->eh_info.err_mask |= AC_ERR_DEV;
140 				qc->flags |= ATA_QCFLAG_FAILED;
141 			}
142 
143 			dev->sata_dev.fis[3] = 0x04; /* status err */
144 			dev->sata_dev.fis[2] = ATA_ERR;
145 		}
146 	}
147 
148 	qc->lldd_task = NULL;
149 	ata_qc_complete(qc);
150 	spin_unlock_irqrestore(ap->lock, flags);
151 
152 qc_already_gone:
153 	sas_free_task(task);
154 }
155 
156 static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
157 	__must_hold(ap->lock)
158 {
159 	struct sas_task *task;
160 	struct scatterlist *sg;
161 	int ret = AC_ERR_SYSTEM;
162 	unsigned int si, xfer = 0;
163 	struct ata_port *ap = qc->ap;
164 	struct domain_device *dev = ap->private_data;
165 	struct sas_ha_struct *sas_ha = dev->port->ha;
166 	struct Scsi_Host *host = sas_ha->core.shost;
167 	struct sas_internal *i = to_sas_internal(host->transportt);
168 
169 	/* TODO: we should try to remove that unlock */
170 	spin_unlock(ap->lock);
171 
172 	/* If the device fell off, no sense in issuing commands */
173 	if (test_bit(SAS_DEV_GONE, &dev->state))
174 		goto out;
175 
176 	task = sas_alloc_task(GFP_ATOMIC);
177 	if (!task)
178 		goto out;
179 	task->dev = dev;
180 	task->task_proto = SAS_PROTOCOL_STP;
181 	task->task_done = sas_ata_task_done;
182 
183 	if (qc->tf.command == ATA_CMD_FPDMA_WRITE ||
184 	    qc->tf.command == ATA_CMD_FPDMA_READ ||
185 	    qc->tf.command == ATA_CMD_FPDMA_RECV ||
186 	    qc->tf.command == ATA_CMD_FPDMA_SEND ||
187 	    qc->tf.command == ATA_CMD_NCQ_NON_DATA) {
188 		/* Need to zero out the tag libata assigned us */
189 		qc->tf.nsect = 0;
190 	}
191 
192 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, (u8 *)&task->ata_task.fis);
193 	task->uldd_task = qc;
194 	if (ata_is_atapi(qc->tf.protocol)) {
195 		memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
196 		task->total_xfer_len = qc->nbytes;
197 		task->num_scatter = qc->n_elem;
198 		task->data_dir = qc->dma_dir;
199 	} else if (qc->tf.protocol == ATA_PROT_NODATA) {
200 		task->data_dir = DMA_NONE;
201 	} else {
202 		for_each_sg(qc->sg, sg, qc->n_elem, si)
203 			xfer += sg_dma_len(sg);
204 
205 		task->total_xfer_len = xfer;
206 		task->num_scatter = si;
207 		task->data_dir = qc->dma_dir;
208 	}
209 	task->scatter = qc->sg;
210 	task->ata_task.retry_count = 1;
211 	task->task_state_flags = SAS_TASK_STATE_PENDING;
212 	qc->lldd_task = task;
213 
214 	task->ata_task.use_ncq = ata_is_ncq(qc->tf.protocol);
215 	task->ata_task.dma_xfer = ata_is_dma(qc->tf.protocol);
216 
217 	if (qc->scsicmd)
218 		ASSIGN_SAS_TASK(qc->scsicmd, task);
219 
220 	ret = i->dft->lldd_execute_task(task, GFP_ATOMIC);
221 	if (ret) {
222 		pr_debug("lldd_execute_task returned: %d\n", ret);
223 
224 		if (qc->scsicmd)
225 			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
226 		sas_free_task(task);
227 		qc->lldd_task = NULL;
228 		ret = AC_ERR_SYSTEM;
229 	}
230 
231  out:
232 	spin_lock(ap->lock);
233 	return ret;
234 }
235 
236 static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
237 {
238 	struct domain_device *dev = qc->ap->private_data;
239 
240 	ata_tf_from_fis(dev->sata_dev.fis, &qc->result_tf);
241 	return true;
242 }
243 
244 static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
245 {
246 	return to_sas_internal(dev->port->ha->core.shost->transportt);
247 }
248 
249 static int sas_get_ata_command_set(struct domain_device *dev);
250 
251 int sas_get_ata_info(struct domain_device *dev, struct ex_phy *phy)
252 {
253 	if (phy->attached_tproto & SAS_PROTOCOL_STP)
254 		dev->tproto = phy->attached_tproto;
255 	if (phy->attached_sata_dev)
256 		dev->tproto |= SAS_SATA_DEV;
257 
258 	if (phy->attached_dev_type == SAS_SATA_PENDING)
259 		dev->dev_type = SAS_SATA_PENDING;
260 	else {
261 		int res;
262 
263 		dev->dev_type = SAS_SATA_DEV;
264 		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
265 					      &dev->sata_dev.rps_resp);
266 		if (res) {
267 			pr_debug("report phy sata to %016llx:%02d returned 0x%x\n",
268 				 SAS_ADDR(dev->parent->sas_addr),
269 				 phy->phy_id, res);
270 			return res;
271 		}
272 		memcpy(dev->frame_rcvd, &dev->sata_dev.rps_resp.rps.fis,
273 		       sizeof(struct dev_to_host_fis));
274 		dev->sata_dev.class = sas_get_ata_command_set(dev);
275 	}
276 	return 0;
277 }
278 
279 static int sas_ata_clear_pending(struct domain_device *dev, struct ex_phy *phy)
280 {
281 	int res;
282 
283 	/* we weren't pending, so successfully end the reset sequence now */
284 	if (dev->dev_type != SAS_SATA_PENDING)
285 		return 1;
286 
287 	/* hmmm, if this succeeds do we need to repost the domain_device to the
288 	 * lldd so it can pick up new parameters?
289 	 */
290 	res = sas_get_ata_info(dev, phy);
291 	if (res)
292 		return 0; /* retry */
293 	else
294 		return 1;
295 }
296 
297 static int smp_ata_check_ready(struct ata_link *link)
298 {
299 	int res;
300 	struct ata_port *ap = link->ap;
301 	struct domain_device *dev = ap->private_data;
302 	struct domain_device *ex_dev = dev->parent;
303 	struct sas_phy *phy = sas_get_local_phy(dev);
304 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy->number];
305 
306 	res = sas_ex_phy_discover(ex_dev, phy->number);
307 	sas_put_local_phy(phy);
308 
309 	/* break the wait early if the expander is unreachable,
310 	 * otherwise keep polling
311 	 */
312 	if (res == -ECOMM)
313 		return res;
314 	if (res != SMP_RESP_FUNC_ACC)
315 		return 0;
316 
317 	switch (ex_phy->attached_dev_type) {
318 	case SAS_SATA_PENDING:
319 		return 0;
320 	case SAS_END_DEVICE:
321 		if (ex_phy->attached_sata_dev)
322 			return sas_ata_clear_pending(dev, ex_phy);
323 		fallthrough;
324 	default:
325 		return -ENODEV;
326 	}
327 }
328 
329 static int local_ata_check_ready(struct ata_link *link)
330 {
331 	struct ata_port *ap = link->ap;
332 	struct domain_device *dev = ap->private_data;
333 	struct sas_internal *i = dev_to_sas_internal(dev);
334 
335 	if (i->dft->lldd_ata_check_ready)
336 		return i->dft->lldd_ata_check_ready(dev);
337 	else {
338 		/* lldd's that don't implement 'ready' checking get the
339 		 * old default behavior of not coordinating reset
340 		 * recovery with libata
341 		 */
342 		return 1;
343 	}
344 }
345 
346 static int sas_ata_printk(const char *level, const struct domain_device *ddev,
347 			  const char *fmt, ...)
348 {
349 	struct ata_port *ap = ddev->sata_dev.ap;
350 	struct device *dev = &ddev->rphy->dev;
351 	struct va_format vaf;
352 	va_list args;
353 	int r;
354 
355 	va_start(args, fmt);
356 
357 	vaf.fmt = fmt;
358 	vaf.va = &args;
359 
360 	r = printk("%s" SAS_FMT "ata%u: %s: %pV",
361 		   level, ap->print_id, dev_name(dev), &vaf);
362 
363 	va_end(args);
364 
365 	return r;
366 }
367 
368 static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
369 			      unsigned long deadline)
370 {
371 	int ret = 0, res;
372 	struct sas_phy *phy;
373 	struct ata_port *ap = link->ap;
374 	int (*check_ready)(struct ata_link *link);
375 	struct domain_device *dev = ap->private_data;
376 	struct sas_internal *i = dev_to_sas_internal(dev);
377 
378 	res = i->dft->lldd_I_T_nexus_reset(dev);
379 	if (res == -ENODEV)
380 		return res;
381 
382 	if (res != TMF_RESP_FUNC_COMPLETE)
383 		sas_ata_printk(KERN_DEBUG, dev, "Unable to reset ata device?\n");
384 
385 	phy = sas_get_local_phy(dev);
386 	if (scsi_is_sas_phy_local(phy))
387 		check_ready = local_ata_check_ready;
388 	else
389 		check_ready = smp_ata_check_ready;
390 	sas_put_local_phy(phy);
391 
392 	ret = ata_wait_after_reset(link, deadline, check_ready);
393 	if (ret && ret != -EAGAIN)
394 		sas_ata_printk(KERN_ERR, dev, "reset failed (errno=%d)\n", ret);
395 
396 	*class = dev->sata_dev.class;
397 
398 	ap->cbl = ATA_CBL_SATA;
399 	return ret;
400 }
401 
402 /*
403  * notify the lldd to forget the sas_task for this internal ata command
404  * that bypasses scsi-eh
405  */
406 static void sas_ata_internal_abort(struct sas_task *task)
407 {
408 	struct sas_internal *si = dev_to_sas_internal(task->dev);
409 	unsigned long flags;
410 	int res;
411 
412 	spin_lock_irqsave(&task->task_state_lock, flags);
413 	if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
414 	    task->task_state_flags & SAS_TASK_STATE_DONE) {
415 		spin_unlock_irqrestore(&task->task_state_lock, flags);
416 		pr_debug("%s: Task %p already finished.\n", __func__, task);
417 		goto out;
418 	}
419 	task->task_state_flags |= SAS_TASK_STATE_ABORTED;
420 	spin_unlock_irqrestore(&task->task_state_lock, flags);
421 
422 	res = si->dft->lldd_abort_task(task);
423 
424 	spin_lock_irqsave(&task->task_state_lock, flags);
425 	if (task->task_state_flags & SAS_TASK_STATE_DONE ||
426 	    res == TMF_RESP_FUNC_COMPLETE) {
427 		spin_unlock_irqrestore(&task->task_state_lock, flags);
428 		goto out;
429 	}
430 
431 	/* XXX we are not prepared to deal with ->lldd_abort_task()
432 	 * failures.  TODO: lldds need to unconditionally forget about
433 	 * aborted ata tasks, otherwise we (likely) leak the sas task
434 	 * here
435 	 */
436 	pr_warn("%s: Task %p leaked.\n", __func__, task);
437 
438 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
439 		task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
440 	spin_unlock_irqrestore(&task->task_state_lock, flags);
441 
442 	return;
443  out:
444 	sas_free_task(task);
445 }
446 
447 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
448 {
449 	if (qc->flags & ATA_QCFLAG_FAILED)
450 		qc->err_mask |= AC_ERR_OTHER;
451 
452 	if (qc->err_mask) {
453 		/*
454 		 * Find the sas_task and kill it.  By this point, libata
455 		 * has decided to kill the qc and has frozen the port.
456 		 * In this state sas_ata_task_done() will no longer free
457 		 * the sas_task, so we need to notify the lldd (via
458 		 * ->lldd_abort_task) that the task is dead and free it
459 		 *  ourselves.
460 		 */
461 		struct sas_task *task = qc->lldd_task;
462 
463 		qc->lldd_task = NULL;
464 		if (!task)
465 			return;
466 		task->uldd_task = NULL;
467 		sas_ata_internal_abort(task);
468 	}
469 }
470 
471 
472 static void sas_ata_set_dmamode(struct ata_port *ap, struct ata_device *ata_dev)
473 {
474 	struct domain_device *dev = ap->private_data;
475 	struct sas_internal *i = dev_to_sas_internal(dev);
476 
477 	if (i->dft->lldd_ata_set_dmamode)
478 		i->dft->lldd_ata_set_dmamode(dev);
479 }
480 
481 static void sas_ata_sched_eh(struct ata_port *ap)
482 {
483 	struct domain_device *dev = ap->private_data;
484 	struct sas_ha_struct *ha = dev->port->ha;
485 	unsigned long flags;
486 
487 	spin_lock_irqsave(&ha->lock, flags);
488 	if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
489 		ha->eh_active++;
490 	ata_std_sched_eh(ap);
491 	spin_unlock_irqrestore(&ha->lock, flags);
492 }
493 
494 void sas_ata_end_eh(struct ata_port *ap)
495 {
496 	struct domain_device *dev = ap->private_data;
497 	struct sas_ha_struct *ha = dev->port->ha;
498 	unsigned long flags;
499 
500 	spin_lock_irqsave(&ha->lock, flags);
501 	if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
502 		ha->eh_active--;
503 	spin_unlock_irqrestore(&ha->lock, flags);
504 }
505 
506 static int sas_ata_prereset(struct ata_link *link, unsigned long deadline)
507 {
508 	struct ata_port *ap = link->ap;
509 	struct domain_device *dev = ap->private_data;
510 	struct sas_phy *local_phy = sas_get_local_phy(dev);
511 	int res = 0;
512 
513 	if (!local_phy->enabled || test_bit(SAS_DEV_GONE, &dev->state))
514 		res = -ENOENT;
515 	sas_put_local_phy(local_phy);
516 
517 	return res;
518 }
519 
520 static struct ata_port_operations sas_sata_ops = {
521 	.prereset		= sas_ata_prereset,
522 	.hardreset		= sas_ata_hard_reset,
523 	.error_handler		= ata_std_error_handler,
524 	.post_internal_cmd	= sas_ata_post_internal,
525 	.qc_defer               = ata_std_qc_defer,
526 	.qc_prep		= ata_noop_qc_prep,
527 	.qc_issue		= sas_ata_qc_issue,
528 	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
529 	.port_start		= ata_sas_port_start,
530 	.port_stop		= ata_sas_port_stop,
531 	.set_dmamode		= sas_ata_set_dmamode,
532 	.sched_eh		= sas_ata_sched_eh,
533 	.end_eh			= sas_ata_end_eh,
534 };
535 
536 static struct ata_port_info sata_port_info = {
537 	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
538 		 ATA_FLAG_SAS_HOST | ATA_FLAG_FPDMA_AUX,
539 	.pio_mask = ATA_PIO4,
540 	.mwdma_mask = ATA_MWDMA2,
541 	.udma_mask = ATA_UDMA6,
542 	.port_ops = &sas_sata_ops
543 };
544 
545 int sas_ata_init(struct domain_device *found_dev)
546 {
547 	struct sas_ha_struct *ha = found_dev->port->ha;
548 	struct Scsi_Host *shost = ha->core.shost;
549 	struct ata_host *ata_host;
550 	struct ata_port *ap;
551 	int rc;
552 
553 	ata_host = kzalloc(sizeof(*ata_host), GFP_KERNEL);
554 	if (!ata_host)	{
555 		pr_err("ata host alloc failed.\n");
556 		return -ENOMEM;
557 	}
558 
559 	ata_host_init(ata_host, ha->dev, &sas_sata_ops);
560 
561 	ap = ata_sas_port_alloc(ata_host, &sata_port_info, shost);
562 	if (!ap) {
563 		pr_err("ata_sas_port_alloc failed.\n");
564 		rc = -ENODEV;
565 		goto free_host;
566 	}
567 
568 	ap->private_data = found_dev;
569 	ap->cbl = ATA_CBL_SATA;
570 	ap->scsi_host = shost;
571 	rc = ata_sas_port_init(ap);
572 	if (rc)
573 		goto destroy_port;
574 
575 	rc = ata_sas_tport_add(ata_host->dev, ap);
576 	if (rc)
577 		goto destroy_port;
578 
579 	found_dev->sata_dev.ata_host = ata_host;
580 	found_dev->sata_dev.ap = ap;
581 
582 	return 0;
583 
584 destroy_port:
585 	ata_sas_port_destroy(ap);
586 free_host:
587 	ata_host_put(ata_host);
588 	return rc;
589 }
590 
591 void sas_ata_task_abort(struct sas_task *task)
592 {
593 	struct ata_queued_cmd *qc = task->uldd_task;
594 	struct completion *waiting;
595 
596 	/* Bounce SCSI-initiated commands to the SCSI EH */
597 	if (qc->scsicmd) {
598 		blk_abort_request(qc->scsicmd->request);
599 		return;
600 	}
601 
602 	/* Internal command, fake a timeout and complete. */
603 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
604 	qc->flags |= ATA_QCFLAG_FAILED;
605 	qc->err_mask |= AC_ERR_TIMEOUT;
606 	waiting = qc->private_data;
607 	complete(waiting);
608 }
609 
610 static int sas_get_ata_command_set(struct domain_device *dev)
611 {
612 	struct dev_to_host_fis *fis =
613 		(struct dev_to_host_fis *) dev->frame_rcvd;
614 	struct ata_taskfile tf;
615 
616 	if (dev->dev_type == SAS_SATA_PENDING)
617 		return ATA_DEV_UNKNOWN;
618 
619 	ata_tf_from_fis((const u8 *)fis, &tf);
620 
621 	return ata_dev_classify(&tf);
622 }
623 
624 void sas_probe_sata(struct asd_sas_port *port)
625 {
626 	struct domain_device *dev, *n;
627 
628 	mutex_lock(&port->ha->disco_mutex);
629 	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
630 		if (!dev_is_sata(dev))
631 			continue;
632 
633 		ata_sas_async_probe(dev->sata_dev.ap);
634 	}
635 	mutex_unlock(&port->ha->disco_mutex);
636 
637 	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
638 		if (!dev_is_sata(dev))
639 			continue;
640 
641 		sas_ata_wait_eh(dev);
642 
643 		/* if libata could not bring the link up, don't surface
644 		 * the device
645 		 */
646 		if (!ata_dev_enabled(sas_to_ata_dev(dev)))
647 			sas_fail_probe(dev, __func__, -ENODEV);
648 	}
649 
650 }
651 
652 static void sas_ata_flush_pm_eh(struct asd_sas_port *port, const char *func)
653 {
654 	struct domain_device *dev, *n;
655 
656 	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
657 		if (!dev_is_sata(dev))
658 			continue;
659 
660 		sas_ata_wait_eh(dev);
661 
662 		/* if libata failed to power manage the device, tear it down */
663 		if (ata_dev_disabled(sas_to_ata_dev(dev)))
664 			sas_fail_probe(dev, func, -ENODEV);
665 	}
666 }
667 
668 void sas_suspend_sata(struct asd_sas_port *port)
669 {
670 	struct domain_device *dev;
671 
672 	mutex_lock(&port->ha->disco_mutex);
673 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
674 		struct sata_device *sata;
675 
676 		if (!dev_is_sata(dev))
677 			continue;
678 
679 		sata = &dev->sata_dev;
680 		if (sata->ap->pm_mesg.event == PM_EVENT_SUSPEND)
681 			continue;
682 
683 		ata_sas_port_suspend(sata->ap);
684 	}
685 	mutex_unlock(&port->ha->disco_mutex);
686 
687 	sas_ata_flush_pm_eh(port, __func__);
688 }
689 
690 void sas_resume_sata(struct asd_sas_port *port)
691 {
692 	struct domain_device *dev;
693 
694 	mutex_lock(&port->ha->disco_mutex);
695 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
696 		struct sata_device *sata;
697 
698 		if (!dev_is_sata(dev))
699 			continue;
700 
701 		sata = &dev->sata_dev;
702 		if (sata->ap->pm_mesg.event == PM_EVENT_ON)
703 			continue;
704 
705 		ata_sas_port_resume(sata->ap);
706 	}
707 	mutex_unlock(&port->ha->disco_mutex);
708 
709 	sas_ata_flush_pm_eh(port, __func__);
710 }
711 
712 /**
713  * sas_discover_sata - discover an STP/SATA domain device
714  * @dev: pointer to struct domain_device of interest
715  *
716  * Devices directly attached to a HA port, have no parents.  All other
717  * devices do, and should have their "parent" pointer set appropriately
718  * before calling this function.
719  */
720 int sas_discover_sata(struct domain_device *dev)
721 {
722 	if (dev->dev_type == SAS_SATA_PM)
723 		return -ENODEV;
724 
725 	dev->sata_dev.class = sas_get_ata_command_set(dev);
726 	sas_fill_in_rphy(dev, dev->rphy);
727 
728 	return sas_notify_lldd_dev_found(dev);
729 }
730 
731 static void async_sas_ata_eh(void *data, async_cookie_t cookie)
732 {
733 	struct domain_device *dev = data;
734 	struct ata_port *ap = dev->sata_dev.ap;
735 	struct sas_ha_struct *ha = dev->port->ha;
736 
737 	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
738 	ata_scsi_port_error_handler(ha->core.shost, ap);
739 	sas_put_device(dev);
740 }
741 
742 void sas_ata_strategy_handler(struct Scsi_Host *shost)
743 {
744 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
745 	ASYNC_DOMAIN_EXCLUSIVE(async);
746 	int i;
747 
748 	/* it's ok to defer revalidation events during ata eh, these
749 	 * disks are in one of three states:
750 	 * 1/ present for initial domain discovery, and these
751 	 *    resets will cause bcn flutters
752 	 * 2/ hot removed, we'll discover that after eh fails
753 	 * 3/ hot added after initial discovery, lost the race, and need
754 	 *    to catch the next train.
755 	 */
756 	sas_disable_revalidation(sas_ha);
757 
758 	spin_lock_irq(&sas_ha->phy_port_lock);
759 	for (i = 0; i < sas_ha->num_phys; i++) {
760 		struct asd_sas_port *port = sas_ha->sas_port[i];
761 		struct domain_device *dev;
762 
763 		spin_lock(&port->dev_list_lock);
764 		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
765 			if (!dev_is_sata(dev))
766 				continue;
767 
768 			/* hold a reference over eh since we may be
769 			 * racing with final remove once all commands
770 			 * are completed
771 			 */
772 			kref_get(&dev->kref);
773 
774 			async_schedule_domain(async_sas_ata_eh, dev, &async);
775 		}
776 		spin_unlock(&port->dev_list_lock);
777 	}
778 	spin_unlock_irq(&sas_ha->phy_port_lock);
779 
780 	async_synchronize_full_domain(&async);
781 
782 	sas_enable_revalidation(sas_ha);
783 }
784 
785 void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
786 		struct list_head *done_q)
787 {
788 	struct scsi_cmnd *cmd, *n;
789 	struct domain_device *eh_dev;
790 
791 	do {
792 		LIST_HEAD(sata_q);
793 		eh_dev = NULL;
794 
795 		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
796 			struct domain_device *ddev = cmd_to_domain_dev(cmd);
797 
798 			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
799 				continue;
800 			if (eh_dev && eh_dev != ddev)
801 				continue;
802 			eh_dev = ddev;
803 			list_move(&cmd->eh_entry, &sata_q);
804 		}
805 
806 		if (!list_empty(&sata_q)) {
807 			struct ata_port *ap = eh_dev->sata_dev.ap;
808 
809 			sas_ata_printk(KERN_DEBUG, eh_dev, "cmd error handler\n");
810 			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
811 			/*
812 			 * ata's error handler may leave the cmd on the list
813 			 * so make sure they don't remain on a stack list
814 			 * about to go out of scope.
815 			 *
816 			 * This looks strange, since the commands are
817 			 * now part of no list, but the next error
818 			 * action will be ata_port_error_handler()
819 			 * which takes no list and sweeps them up
820 			 * anyway from the ata tag array.
821 			 */
822 			while (!list_empty(&sata_q))
823 				list_del_init(sata_q.next);
824 		}
825 	} while (eh_dev);
826 }
827 
828 void sas_ata_schedule_reset(struct domain_device *dev)
829 {
830 	struct ata_eh_info *ehi;
831 	struct ata_port *ap;
832 	unsigned long flags;
833 
834 	if (!dev_is_sata(dev))
835 		return;
836 
837 	ap = dev->sata_dev.ap;
838 	ehi = &ap->link.eh_info;
839 
840 	spin_lock_irqsave(ap->lock, flags);
841 	ehi->err_mask |= AC_ERR_TIMEOUT;
842 	ehi->action |= ATA_EH_RESET;
843 	ata_port_schedule_eh(ap);
844 	spin_unlock_irqrestore(ap->lock, flags);
845 }
846 EXPORT_SYMBOL_GPL(sas_ata_schedule_reset);
847 
848 void sas_ata_wait_eh(struct domain_device *dev)
849 {
850 	struct ata_port *ap;
851 
852 	if (!dev_is_sata(dev))
853 		return;
854 
855 	ap = dev->sata_dev.ap;
856 	ata_port_wait_eh(ap);
857 }
858