1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Serial Attached SCSI (SAS) class SCSI Host glue.
4 *
5 * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
6 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
7 */
8
9#include <linux/kthread.h>
10#include <linux/firmware.h>
11#include <linux/export.h>
12#include <linux/ctype.h>
13#include <linux/kernel.h>
14
15#include "sas_internal.h"
16
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_eh.h>
22#include <scsi/scsi_transport.h>
23#include <scsi/scsi_transport_sas.h>
24#include <scsi/sas_ata.h>
25#include "scsi_sas_internal.h"
26#include "scsi_transport_api.h"
27#include "scsi_priv.h"
28
29#include <linux/err.h>
30#include <linux/blkdev.h>
31#include <linux/freezer.h>
32#include <linux/gfp.h>
33#include <linux/scatterlist.h>
34#include <linux/libata.h>
35
36/* record final status and free the task */
37static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
38{
39	struct task_status_struct *ts = &task->task_status;
40	enum scsi_host_status hs = DID_OK;
41	enum exec_status stat = SAS_SAM_STAT_GOOD;
42
43	if (ts->resp == SAS_TASK_UNDELIVERED) {
44		/* transport error */
45		hs = DID_NO_CONNECT;
46	} else { /* ts->resp == SAS_TASK_COMPLETE */
47		/* task delivered, what happened afterwards? */
48		switch (ts->stat) {
49		case SAS_DEV_NO_RESPONSE:
50		case SAS_INTERRUPTED:
51		case SAS_PHY_DOWN:
52		case SAS_NAK_R_ERR:
53		case SAS_OPEN_TO:
54			hs = DID_NO_CONNECT;
55			break;
56		case SAS_DATA_UNDERRUN:
57			scsi_set_resid(sc, ts->residual);
58			if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
59				hs = DID_ERROR;
60			break;
61		case SAS_DATA_OVERRUN:
62			hs = DID_ERROR;
63			break;
64		case SAS_QUEUE_FULL:
65			hs = DID_SOFT_ERROR; /* retry */
66			break;
67		case SAS_DEVICE_UNKNOWN:
68			hs = DID_BAD_TARGET;
69			break;
70		case SAS_OPEN_REJECT:
71			if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
72				hs = DID_SOFT_ERROR; /* retry */
73			else
74				hs = DID_ERROR;
75			break;
76		case SAS_PROTO_RESPONSE:
77			pr_notice("LLDD:%s sent SAS_PROTO_RESP for an SSP task; please report this\n",
78				  task->dev->port->ha->sas_ha_name);
79			break;
80		case SAS_ABORTED_TASK:
81			hs = DID_ABORT;
82			break;
83		case SAS_SAM_STAT_CHECK_CONDITION:
84			memcpy(sc->sense_buffer, ts->buf,
85			       min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
86			stat = SAS_SAM_STAT_CHECK_CONDITION;
87			break;
88		default:
89			stat = ts->stat;
90			break;
91		}
92	}
93
94	sc->result = (hs << 16) | stat;
95	ASSIGN_SAS_TASK(sc, NULL);
96	sas_free_task(task);
97}
98
99static void sas_scsi_task_done(struct sas_task *task)
100{
101	struct scsi_cmnd *sc = task->uldd_task;
102	struct domain_device *dev = task->dev;
103	struct sas_ha_struct *ha = dev->port->ha;
104	unsigned long flags;
105
106	spin_lock_irqsave(&dev->done_lock, flags);
107	if (test_bit(SAS_HA_FROZEN, &ha->state))
108		task = NULL;
109	else
110		ASSIGN_SAS_TASK(sc, NULL);
111	spin_unlock_irqrestore(&dev->done_lock, flags);
112
113	if (unlikely(!task)) {
114		/* task will be completed by the error handler */
115		pr_debug("task done but aborted\n");
116		return;
117	}
118
119	if (unlikely(!sc)) {
120		pr_debug("task_done called with non existing SCSI cmnd!\n");
121		sas_free_task(task);
122		return;
123	}
124
125	sas_end_task(sc, task);
126	scsi_done(sc);
127}
128
129static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
130					       struct domain_device *dev,
131					       gfp_t gfp_flags)
132{
133	struct sas_task *task = sas_alloc_task(gfp_flags);
134	struct scsi_lun lun;
135
136	if (!task)
137		return NULL;
138
139	task->uldd_task = cmd;
140	ASSIGN_SAS_TASK(cmd, task);
141
142	task->dev = dev;
143	task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
144
145	int_to_scsilun(cmd->device->lun, &lun);
146	memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
147	task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
148	task->ssp_task.cmd = cmd;
149
150	task->scatter = scsi_sglist(cmd);
151	task->num_scatter = scsi_sg_count(cmd);
152	task->total_xfer_len = scsi_bufflen(cmd);
153	task->data_dir = cmd->sc_data_direction;
154
155	task->task_done = sas_scsi_task_done;
156
157	return task;
158}
159
160int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
161{
162	struct sas_internal *i = to_sas_internal(host->transportt);
163	struct domain_device *dev = cmd_to_domain_dev(cmd);
164	struct sas_task *task;
165	int res = 0;
166
167	/* If the device fell off, no sense in issuing commands */
168	if (test_bit(SAS_DEV_GONE, &dev->state)) {
169		cmd->result = DID_BAD_TARGET << 16;
170		goto out_done;
171	}
172
173	if (dev_is_sata(dev)) {
174		spin_lock_irq(dev->sata_dev.ap->lock);
175		res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
176		spin_unlock_irq(dev->sata_dev.ap->lock);
177		return res;
178	}
179
180	task = sas_create_task(cmd, dev, GFP_ATOMIC);
181	if (!task)
182		return SCSI_MLQUEUE_HOST_BUSY;
183
184	res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
185	if (res)
186		goto out_free_task;
187	return 0;
188
189out_free_task:
190	pr_debug("lldd_execute_task returned: %d\n", res);
191	ASSIGN_SAS_TASK(cmd, NULL);
192	sas_free_task(task);
193	if (res == -SAS_QUEUE_FULL)
194		cmd->result = DID_SOFT_ERROR << 16; /* retry */
195	else
196		cmd->result = DID_ERROR << 16;
197out_done:
198	scsi_done(cmd);
199	return 0;
200}
201EXPORT_SYMBOL_GPL(sas_queuecommand);
202
203static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
204{
205	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
206	struct domain_device *dev = cmd_to_domain_dev(cmd);
207	struct sas_task *task = TO_SAS_TASK(cmd);
208
209	/* At this point, we only get called following an actual abort
210	 * of the task, so we should be guaranteed not to be racing with
211	 * any completions from the LLD.  Task is freed after this.
212	 */
213	sas_end_task(cmd, task);
214
215	if (dev_is_sata(dev)) {
216		/* defer commands to libata so that libata EH can
217		 * handle ata qcs correctly
218		 */
219		list_move_tail(&cmd->eh_entry, &sas_ha->eh_ata_q);
220		return;
221	}
222
223	/* now finish the command and move it on to the error
224	 * handler done list, this also takes it off the
225	 * error handler pending list.
226	 */
227	scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
228}
229
230static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
231{
232	struct scsi_cmnd *cmd, *n;
233
234	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
235		if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
236		    cmd->device->lun == my_cmd->device->lun)
237			sas_eh_finish_cmd(cmd);
238	}
239}
240
241static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
242				     struct domain_device *dev)
243{
244	struct scsi_cmnd *cmd, *n;
245
246	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
247		struct domain_device *x = cmd_to_domain_dev(cmd);
248
249		if (x == dev)
250			sas_eh_finish_cmd(cmd);
251	}
252}
253
254static void sas_scsi_clear_queue_port(struct list_head *error_q,
255				      struct asd_sas_port *port)
256{
257	struct scsi_cmnd *cmd, *n;
258
259	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
260		struct domain_device *dev = cmd_to_domain_dev(cmd);
261		struct asd_sas_port *x = dev->port;
262
263		if (x == port)
264			sas_eh_finish_cmd(cmd);
265	}
266}
267
268enum task_disposition {
269	TASK_IS_DONE,
270	TASK_IS_ABORTED,
271	TASK_IS_AT_LU,
272	TASK_IS_NOT_AT_LU,
273	TASK_ABORT_FAILED,
274};
275
276static enum task_disposition sas_scsi_find_task(struct sas_task *task)
277{
278	unsigned long flags;
279	int i, res;
280	struct sas_internal *si =
281		to_sas_internal(task->dev->port->ha->shost->transportt);
282
283	for (i = 0; i < 5; i++) {
284		pr_notice("%s: aborting task 0x%p\n", __func__, task);
285		res = si->dft->lldd_abort_task(task);
286
287		spin_lock_irqsave(&task->task_state_lock, flags);
288		if (task->task_state_flags & SAS_TASK_STATE_DONE) {
289			spin_unlock_irqrestore(&task->task_state_lock, flags);
290			pr_debug("%s: task 0x%p is done\n", __func__, task);
291			return TASK_IS_DONE;
292		}
293		spin_unlock_irqrestore(&task->task_state_lock, flags);
294
295		if (res == TMF_RESP_FUNC_COMPLETE) {
296			pr_notice("%s: task 0x%p is aborted\n",
297				  __func__, task);
298			return TASK_IS_ABORTED;
299		} else if (si->dft->lldd_query_task) {
300			pr_notice("%s: querying task 0x%p\n", __func__, task);
301			res = si->dft->lldd_query_task(task);
302			switch (res) {
303			case TMF_RESP_FUNC_SUCC:
304				pr_notice("%s: task 0x%p at LU\n", __func__,
305					  task);
306				return TASK_IS_AT_LU;
307			case TMF_RESP_FUNC_COMPLETE:
308				pr_notice("%s: task 0x%p not at LU\n",
309					  __func__, task);
310				return TASK_IS_NOT_AT_LU;
311			case TMF_RESP_FUNC_FAILED:
312				pr_notice("%s: task 0x%p failed to abort\n",
313					  __func__, task);
314				return TASK_ABORT_FAILED;
315			default:
316				pr_notice("%s: task 0x%p result code %d not handled\n",
317					  __func__, task, res);
318			}
319		}
320	}
321	return TASK_ABORT_FAILED;
322}
323
324static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
325{
326	int res = TMF_RESP_FUNC_FAILED;
327	struct scsi_lun lun;
328	struct sas_internal *i =
329		to_sas_internal(dev->port->ha->shost->transportt);
330
331	int_to_scsilun(cmd->device->lun, &lun);
332
333	pr_notice("eh: device %016llx LUN 0x%llx has the task\n",
334		  SAS_ADDR(dev->sas_addr),
335		  cmd->device->lun);
336
337	if (i->dft->lldd_abort_task_set)
338		res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
339
340	if (res == TMF_RESP_FUNC_FAILED) {
341		if (i->dft->lldd_clear_task_set)
342			res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
343	}
344
345	if (res == TMF_RESP_FUNC_FAILED) {
346		if (i->dft->lldd_lu_reset)
347			res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
348	}
349
350	return res;
351}
352
353static int sas_recover_I_T(struct domain_device *dev)
354{
355	int res = TMF_RESP_FUNC_FAILED;
356	struct sas_internal *i =
357		to_sas_internal(dev->port->ha->shost->transportt);
358
359	pr_notice("I_T nexus reset for dev %016llx\n",
360		  SAS_ADDR(dev->sas_addr));
361
362	if (i->dft->lldd_I_T_nexus_reset)
363		res = i->dft->lldd_I_T_nexus_reset(dev);
364
365	return res;
366}
367
368/* take a reference on the last known good phy for this device */
369struct sas_phy *sas_get_local_phy(struct domain_device *dev)
370{
371	struct sas_ha_struct *ha = dev->port->ha;
372	struct sas_phy *phy;
373	unsigned long flags;
374
375	/* a published domain device always has a valid phy, it may be
376	 * stale, but it is never NULL
377	 */
378	BUG_ON(!dev->phy);
379
380	spin_lock_irqsave(&ha->phy_port_lock, flags);
381	phy = dev->phy;
382	get_device(&phy->dev);
383	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
384
385	return phy;
386}
387EXPORT_SYMBOL_GPL(sas_get_local_phy);
388
389static int sas_queue_reset(struct domain_device *dev, int reset_type, u64 lun)
390{
391	struct sas_ha_struct *ha = dev->port->ha;
392	int scheduled = 0, tries = 100;
393
394	/* ata: promote lun reset to bus reset */
395	if (dev_is_sata(dev)) {
396		sas_ata_schedule_reset(dev);
397		return SUCCESS;
398	}
399
400	while (!scheduled && tries--) {
401		spin_lock_irq(&ha->lock);
402		if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
403		    !test_bit(reset_type, &dev->state)) {
404			scheduled = 1;
405			ha->eh_active++;
406			list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
407			set_bit(SAS_DEV_EH_PENDING, &dev->state);
408			set_bit(reset_type, &dev->state);
409			int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
410			scsi_schedule_eh(ha->shost);
411		}
412		spin_unlock_irq(&ha->lock);
413
414		if (scheduled)
415			return SUCCESS;
416	}
417
418	pr_warn("%s reset of %s failed\n",
419		reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
420		dev_name(&dev->rphy->dev));
421
422	return FAILED;
423}
424
425int sas_eh_abort_handler(struct scsi_cmnd *cmd)
426{
427	int res = TMF_RESP_FUNC_FAILED;
428	struct sas_task *task = TO_SAS_TASK(cmd);
429	struct Scsi_Host *host = cmd->device->host;
430	struct domain_device *dev = cmd_to_domain_dev(cmd);
431	struct sas_internal *i = to_sas_internal(host->transportt);
432	unsigned long flags;
433
434	if (!i->dft->lldd_abort_task)
435		return FAILED;
436
437	spin_lock_irqsave(host->host_lock, flags);
438	/* We cannot do async aborts for SATA devices */
439	if (dev_is_sata(dev) && !host->host_eh_scheduled) {
440		spin_unlock_irqrestore(host->host_lock, flags);
441		return FAILED;
442	}
443	spin_unlock_irqrestore(host->host_lock, flags);
444
445	if (task)
446		res = i->dft->lldd_abort_task(task);
447	else
448		pr_notice("no task to abort\n");
449	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
450		return SUCCESS;
451
452	return FAILED;
453}
454EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
455
456/* Attempt to send a LUN reset message to a device */
457int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
458{
459	int res;
460	struct scsi_lun lun;
461	struct Scsi_Host *host = cmd->device->host;
462	struct domain_device *dev = cmd_to_domain_dev(cmd);
463	struct sas_internal *i = to_sas_internal(host->transportt);
464
465	if (current != host->ehandler)
466		return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun);
467
468	int_to_scsilun(cmd->device->lun, &lun);
469
470	if (!i->dft->lldd_lu_reset)
471		return FAILED;
472
473	res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
474	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
475		return SUCCESS;
476
477	return FAILED;
478}
479EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
480
481int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
482{
483	int res;
484	struct Scsi_Host *host = cmd->device->host;
485	struct domain_device *dev = cmd_to_domain_dev(cmd);
486	struct sas_internal *i = to_sas_internal(host->transportt);
487
488	if (current != host->ehandler)
489		return sas_queue_reset(dev, SAS_DEV_RESET, 0);
490
491	if (!i->dft->lldd_I_T_nexus_reset)
492		return FAILED;
493
494	res = i->dft->lldd_I_T_nexus_reset(dev);
495	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
496	    res == -ENODEV)
497		return SUCCESS;
498
499	return FAILED;
500}
501EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
502
503/* Try to reset a device */
504static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
505{
506	int res;
507	struct Scsi_Host *shost = cmd->device->host;
508
509	if (!shost->hostt->eh_device_reset_handler)
510		goto try_target_reset;
511
512	res = shost->hostt->eh_device_reset_handler(cmd);
513	if (res == SUCCESS)
514		return res;
515
516try_target_reset:
517	if (shost->hostt->eh_target_reset_handler)
518		return shost->hostt->eh_target_reset_handler(cmd);
519
520	return FAILED;
521}
522
523static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
524{
525	struct scsi_cmnd *cmd, *n;
526	enum task_disposition res = TASK_IS_DONE;
527	int tmf_resp, need_reset;
528	struct sas_internal *i = to_sas_internal(shost->transportt);
529	unsigned long flags;
530	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
531	LIST_HEAD(done);
532
533	/* clean out any commands that won the completion vs eh race */
534	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
535		struct domain_device *dev = cmd_to_domain_dev(cmd);
536		struct sas_task *task;
537
538		spin_lock_irqsave(&dev->done_lock, flags);
539		/* by this point the lldd has either observed
540		 * SAS_HA_FROZEN and is leaving the task alone, or has
541		 * won the race with eh and decided to complete it
542		 */
543		task = TO_SAS_TASK(cmd);
544		spin_unlock_irqrestore(&dev->done_lock, flags);
545
546		if (!task)
547			list_move_tail(&cmd->eh_entry, &done);
548	}
549
550 Again:
551	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
552		struct sas_task *task = TO_SAS_TASK(cmd);
553
554		list_del_init(&cmd->eh_entry);
555
556		spin_lock_irqsave(&task->task_state_lock, flags);
557		need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
558		spin_unlock_irqrestore(&task->task_state_lock, flags);
559
560		if (need_reset) {
561			pr_notice("%s: task 0x%p requests reset\n",
562				  __func__, task);
563			goto reset;
564		}
565
566		pr_debug("trying to find task 0x%p\n", task);
567		res = sas_scsi_find_task(task);
568
569		switch (res) {
570		case TASK_IS_DONE:
571			pr_notice("%s: task 0x%p is done\n", __func__,
572				    task);
573			sas_eh_finish_cmd(cmd);
574			continue;
575		case TASK_IS_ABORTED:
576			pr_notice("%s: task 0x%p is aborted\n",
577				  __func__, task);
578			sas_eh_finish_cmd(cmd);
579			continue;
580		case TASK_IS_AT_LU:
581			pr_info("task 0x%p is at LU: lu recover\n", task);
582 reset:
583			tmf_resp = sas_recover_lu(task->dev, cmd);
584			if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
585				pr_notice("dev %016llx LU 0x%llx is recovered\n",
586					  SAS_ADDR(task->dev),
587					  cmd->device->lun);
588				sas_eh_finish_cmd(cmd);
589				sas_scsi_clear_queue_lu(work_q, cmd);
590				goto Again;
591			}
592			fallthrough;
593		case TASK_IS_NOT_AT_LU:
594		case TASK_ABORT_FAILED:
595			pr_notice("task 0x%p is not at LU: I_T recover\n",
596				  task);
597			tmf_resp = sas_recover_I_T(task->dev);
598			if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
599			    tmf_resp == -ENODEV) {
600				struct domain_device *dev = task->dev;
601				pr_notice("I_T %016llx recovered\n",
602					  SAS_ADDR(task->dev->sas_addr));
603				sas_eh_finish_cmd(cmd);
604				sas_scsi_clear_queue_I_T(work_q, dev);
605				goto Again;
606			}
607			/* Hammer time :-) */
608			try_to_reset_cmd_device(cmd);
609			if (i->dft->lldd_clear_nexus_port) {
610				struct asd_sas_port *port = task->dev->port;
611				pr_debug("clearing nexus for port:%d\n",
612					  port->id);
613				res = i->dft->lldd_clear_nexus_port(port);
614				if (res == TMF_RESP_FUNC_COMPLETE) {
615					pr_notice("clear nexus port:%d succeeded\n",
616						  port->id);
617					sas_eh_finish_cmd(cmd);
618					sas_scsi_clear_queue_port(work_q,
619								  port);
620					goto Again;
621				}
622			}
623			if (i->dft->lldd_clear_nexus_ha) {
624				pr_debug("clear nexus ha\n");
625				res = i->dft->lldd_clear_nexus_ha(ha);
626				if (res == TMF_RESP_FUNC_COMPLETE) {
627					pr_notice("clear nexus ha succeeded\n");
628					sas_eh_finish_cmd(cmd);
629					goto clear_q;
630				}
631			}
632			/* If we are here -- this means that no amount
633			 * of effort could recover from errors.  Quite
634			 * possibly the HA just disappeared.
635			 */
636			pr_err("error from device %016llx, LUN 0x%llx couldn't be recovered in any way\n",
637			       SAS_ADDR(task->dev->sas_addr),
638			       cmd->device->lun);
639
640			sas_eh_finish_cmd(cmd);
641			goto clear_q;
642		}
643	}
644 out:
645	list_splice_tail(&done, work_q);
646	list_splice_tail_init(&ha->eh_ata_q, work_q);
647	return;
648
649 clear_q:
650	pr_debug("--- Exit %s -- clear_q\n", __func__);
651	list_for_each_entry_safe(cmd, n, work_q, eh_entry)
652		sas_eh_finish_cmd(cmd);
653	goto out;
654}
655
656static void sas_eh_handle_resets(struct Scsi_Host *shost)
657{
658	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
659	struct sas_internal *i = to_sas_internal(shost->transportt);
660
661	/* handle directed resets to sas devices */
662	spin_lock_irq(&ha->lock);
663	while (!list_empty(&ha->eh_dev_q)) {
664		struct domain_device *dev;
665		struct ssp_device *ssp;
666
667		ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
668		list_del_init(&ssp->eh_list_node);
669		dev = container_of(ssp, typeof(*dev), ssp_dev);
670		kref_get(&dev->kref);
671		WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
672
673		spin_unlock_irq(&ha->lock);
674
675		if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
676			i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
677
678		if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
679			i->dft->lldd_I_T_nexus_reset(dev);
680
681		sas_put_device(dev);
682		spin_lock_irq(&ha->lock);
683		clear_bit(SAS_DEV_EH_PENDING, &dev->state);
684		ha->eh_active--;
685	}
686	spin_unlock_irq(&ha->lock);
687}
688
689
690void sas_scsi_recover_host(struct Scsi_Host *shost)
691{
692	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
693	LIST_HEAD(eh_work_q);
694	int tries = 0;
695	bool retry;
696
697retry:
698	tries++;
699	retry = true;
700	spin_lock_irq(shost->host_lock);
701	list_splice_init(&shost->eh_cmd_q, &eh_work_q);
702	spin_unlock_irq(shost->host_lock);
703
704	pr_notice("Enter %s busy: %d failed: %d\n",
705		  __func__, scsi_host_busy(shost), shost->host_failed);
706	/*
707	 * Deal with commands that still have SAS tasks (i.e. they didn't
708	 * complete via the normal sas_task completion mechanism),
709	 * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
710	 */
711	set_bit(SAS_HA_FROZEN, &ha->state);
712	sas_eh_handle_sas_errors(shost, &eh_work_q);
713	clear_bit(SAS_HA_FROZEN, &ha->state);
714	if (list_empty(&eh_work_q))
715		goto out;
716
717	/*
718	 * Now deal with SCSI commands that completed ok but have a an error
719	 * code (and hopefully sense data) attached.  This is roughly what
720	 * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
721	 * command we see here has no sas_task and is thus unknown to the HA.
722	 */
723	sas_ata_eh(shost, &eh_work_q);
724	if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
725		scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
726
727out:
728	sas_eh_handle_resets(shost);
729
730	/* now link into libata eh --- if we have any ata devices */
731	sas_ata_strategy_handler(shost);
732
733	scsi_eh_flush_done_q(&ha->eh_done_q);
734
735	/* check if any new eh work was scheduled during the last run */
736	spin_lock_irq(&ha->lock);
737	if (ha->eh_active == 0) {
738		shost->host_eh_scheduled = 0;
739		retry = false;
740	}
741	spin_unlock_irq(&ha->lock);
742
743	if (retry)
744		goto retry;
745
746	pr_notice("--- Exit %s: busy: %d failed: %d tries: %d\n",
747		  __func__, scsi_host_busy(shost),
748		  shost->host_failed, tries);
749}
750
751int sas_ioctl(struct scsi_device *sdev, unsigned int cmd, void __user *arg)
752{
753	struct domain_device *dev = sdev_to_domain_dev(sdev);
754
755	if (dev_is_sata(dev))
756		return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
757
758	return -EINVAL;
759}
760EXPORT_SYMBOL_GPL(sas_ioctl);
761
762struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
763{
764	struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
765	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
766	struct domain_device *found_dev = NULL;
767	int i;
768	unsigned long flags;
769
770	spin_lock_irqsave(&ha->phy_port_lock, flags);
771	for (i = 0; i < ha->num_phys; i++) {
772		struct asd_sas_port *port = ha->sas_port[i];
773		struct domain_device *dev;
774
775		spin_lock(&port->dev_list_lock);
776		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
777			if (rphy == dev->rphy) {
778				found_dev = dev;
779				spin_unlock(&port->dev_list_lock);
780				goto found;
781			}
782		}
783		spin_unlock(&port->dev_list_lock);
784	}
785 found:
786	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
787
788	return found_dev;
789}
790
791int sas_target_alloc(struct scsi_target *starget)
792{
793	struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
794	struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
795
796	if (!found_dev)
797		return -ENODEV;
798
799	kref_get(&found_dev->kref);
800	starget->hostdata = found_dev;
801	return 0;
802}
803EXPORT_SYMBOL_GPL(sas_target_alloc);
804
805#define SAS_DEF_QD 256
806
807int sas_slave_configure(struct scsi_device *scsi_dev)
808{
809	struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
810
811	BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
812
813	if (dev_is_sata(dev)) {
814		ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
815		return 0;
816	}
817
818	sas_read_port_mode_page(scsi_dev);
819
820	if (scsi_dev->tagged_supported) {
821		scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
822	} else {
823		pr_notice("device %016llx, LUN 0x%llx doesn't support TCQ\n",
824			  SAS_ADDR(dev->sas_addr), scsi_dev->lun);
825		scsi_change_queue_depth(scsi_dev, 1);
826	}
827
828	scsi_dev->allow_restart = 1;
829
830	return 0;
831}
832EXPORT_SYMBOL_GPL(sas_slave_configure);
833
834int sas_change_queue_depth(struct scsi_device *sdev, int depth)
835{
836	struct domain_device *dev = sdev_to_domain_dev(sdev);
837
838	if (dev_is_sata(dev))
839		return ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
840
841	if (!sdev->tagged_supported)
842		depth = 1;
843	return scsi_change_queue_depth(sdev, depth);
844}
845EXPORT_SYMBOL_GPL(sas_change_queue_depth);
846
847int sas_bios_param(struct scsi_device *scsi_dev,
848			  struct block_device *bdev,
849			  sector_t capacity, int *hsc)
850{
851	hsc[0] = 255;
852	hsc[1] = 63;
853	sector_div(capacity, 255*63);
854	hsc[2] = capacity;
855
856	return 0;
857}
858EXPORT_SYMBOL_GPL(sas_bios_param);
859
860void sas_task_internal_done(struct sas_task *task)
861{
862	del_timer(&task->slow_task->timer);
863	complete(&task->slow_task->completion);
864}
865
866void sas_task_internal_timedout(struct timer_list *t)
867{
868	struct sas_task_slow *slow = from_timer(slow, t, timer);
869	struct sas_task *task = slow->task;
870	bool is_completed = true;
871	unsigned long flags;
872
873	spin_lock_irqsave(&task->task_state_lock, flags);
874	if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
875		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
876		is_completed = false;
877	}
878	spin_unlock_irqrestore(&task->task_state_lock, flags);
879
880	if (!is_completed)
881		complete(&task->slow_task->completion);
882}
883
884#define TASK_TIMEOUT			(20 * HZ)
885#define TASK_RETRY			3
886
887static int sas_execute_internal_abort(struct domain_device *device,
888				      enum sas_internal_abort type, u16 tag,
889				      unsigned int qid, void *data)
890{
891	struct sas_ha_struct *ha = device->port->ha;
892	struct sas_internal *i = to_sas_internal(ha->shost->transportt);
893	struct sas_task *task = NULL;
894	int res, retry;
895
896	for (retry = 0; retry < TASK_RETRY; retry++) {
897		task = sas_alloc_slow_task(GFP_KERNEL);
898		if (!task)
899			return -ENOMEM;
900
901		task->dev = device;
902		task->task_proto = SAS_PROTOCOL_INTERNAL_ABORT;
903		task->task_done = sas_task_internal_done;
904		task->slow_task->timer.function = sas_task_internal_timedout;
905		task->slow_task->timer.expires = jiffies + TASK_TIMEOUT;
906		add_timer(&task->slow_task->timer);
907
908		task->abort_task.tag = tag;
909		task->abort_task.type = type;
910		task->abort_task.qid = qid;
911
912		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
913		if (res) {
914			del_timer_sync(&task->slow_task->timer);
915			pr_err("Executing internal abort failed %016llx (%d)\n",
916			       SAS_ADDR(device->sas_addr), res);
917			break;
918		}
919
920		wait_for_completion(&task->slow_task->completion);
921		res = TMF_RESP_FUNC_FAILED;
922
923		/* Even if the internal abort timed out, return direct. */
924		if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
925			bool quit = true;
926
927			if (i->dft->lldd_abort_timeout)
928				quit = i->dft->lldd_abort_timeout(task, data);
929			else
930				pr_err("Internal abort: timeout %016llx\n",
931				       SAS_ADDR(device->sas_addr));
932			res = -EIO;
933			if (quit)
934				break;
935		}
936
937		if (task->task_status.resp == SAS_TASK_COMPLETE &&
938			task->task_status.stat == SAS_SAM_STAT_GOOD) {
939			res = TMF_RESP_FUNC_COMPLETE;
940			break;
941		}
942
943		if (task->task_status.resp == SAS_TASK_COMPLETE &&
944			task->task_status.stat == TMF_RESP_FUNC_SUCC) {
945			res = TMF_RESP_FUNC_SUCC;
946			break;
947		}
948
949		pr_err("Internal abort: task to dev %016llx response: 0x%x status 0x%x\n",
950		       SAS_ADDR(device->sas_addr), task->task_status.resp,
951		       task->task_status.stat);
952		sas_free_task(task);
953		task = NULL;
954	}
955	BUG_ON(retry == TASK_RETRY && task != NULL);
956	sas_free_task(task);
957	return res;
958}
959
960int sas_execute_internal_abort_single(struct domain_device *device, u16 tag,
961				      unsigned int qid, void *data)
962{
963	return sas_execute_internal_abort(device, SAS_INTERNAL_ABORT_SINGLE,
964					  tag, qid, data);
965}
966EXPORT_SYMBOL_GPL(sas_execute_internal_abort_single);
967
968int sas_execute_internal_abort_dev(struct domain_device *device,
969				   unsigned int qid, void *data)
970{
971	return sas_execute_internal_abort(device, SAS_INTERNAL_ABORT_DEV,
972					  SCSI_NO_TAG, qid, data);
973}
974EXPORT_SYMBOL_GPL(sas_execute_internal_abort_dev);
975
976int sas_execute_tmf(struct domain_device *device, void *parameter,
977		    int para_len, int force_phy_id,
978		    struct sas_tmf_task *tmf)
979{
980	struct sas_task *task;
981	struct sas_internal *i =
982		to_sas_internal(device->port->ha->shost->transportt);
983	int res, retry;
984
985	for (retry = 0; retry < TASK_RETRY; retry++) {
986		task = sas_alloc_slow_task(GFP_KERNEL);
987		if (!task)
988			return -ENOMEM;
989
990		task->dev = device;
991		task->task_proto = device->tproto;
992
993		if (dev_is_sata(device)) {
994			task->ata_task.device_control_reg_update = 1;
995			if (force_phy_id >= 0) {
996				task->ata_task.force_phy = true;
997				task->ata_task.force_phy_id = force_phy_id;
998			}
999			memcpy(&task->ata_task.fis, parameter, para_len);
1000		} else {
1001			memcpy(&task->ssp_task, parameter, para_len);
1002		}
1003
1004		task->task_done = sas_task_internal_done;
1005		task->tmf = tmf;
1006
1007		task->slow_task->timer.function = sas_task_internal_timedout;
1008		task->slow_task->timer.expires = jiffies + TASK_TIMEOUT;
1009		add_timer(&task->slow_task->timer);
1010
1011		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
1012		if (res) {
1013			del_timer_sync(&task->slow_task->timer);
1014			pr_err("executing TMF task failed %016llx (%d)\n",
1015			       SAS_ADDR(device->sas_addr), res);
1016			break;
1017		}
1018
1019		wait_for_completion(&task->slow_task->completion);
1020
1021		if (i->dft->lldd_tmf_exec_complete)
1022			i->dft->lldd_tmf_exec_complete(device);
1023
1024		res = TMF_RESP_FUNC_FAILED;
1025
1026		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
1027			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
1028				pr_err("TMF task timeout for %016llx and not done\n",
1029				       SAS_ADDR(device->sas_addr));
1030				if (i->dft->lldd_tmf_aborted)
1031					i->dft->lldd_tmf_aborted(task);
1032				break;
1033			}
1034			pr_warn("TMF task timeout for %016llx and done\n",
1035				SAS_ADDR(device->sas_addr));
1036		}
1037
1038		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1039		    task->task_status.stat == TMF_RESP_FUNC_COMPLETE) {
1040			res = TMF_RESP_FUNC_COMPLETE;
1041			break;
1042		}
1043
1044		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1045		    task->task_status.stat == TMF_RESP_FUNC_SUCC) {
1046			res = TMF_RESP_FUNC_SUCC;
1047			break;
1048		}
1049
1050		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1051		    task->task_status.stat == SAS_DATA_UNDERRUN) {
1052			/* no error, but return the number of bytes of
1053			 * underrun
1054			 */
1055			pr_warn("TMF task to dev %016llx resp: 0x%x sts 0x%x underrun\n",
1056				SAS_ADDR(device->sas_addr),
1057				task->task_status.resp,
1058				task->task_status.stat);
1059			res = task->task_status.residual;
1060			break;
1061		}
1062
1063		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1064		    task->task_status.stat == SAS_DATA_OVERRUN) {
1065			pr_warn("TMF task blocked task error %016llx\n",
1066				SAS_ADDR(device->sas_addr));
1067			res = -EMSGSIZE;
1068			break;
1069		}
1070
1071		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1072		    task->task_status.stat == SAS_OPEN_REJECT) {
1073			pr_warn("TMF task open reject failed  %016llx\n",
1074				SAS_ADDR(device->sas_addr));
1075			res = -EIO;
1076		} else {
1077			pr_warn("TMF task to dev %016llx resp: 0x%x status 0x%x\n",
1078				SAS_ADDR(device->sas_addr),
1079				task->task_status.resp,
1080				task->task_status.stat);
1081		}
1082		sas_free_task(task);
1083		task = NULL;
1084	}
1085
1086	if (retry == TASK_RETRY)
1087		pr_warn("executing TMF for %016llx failed after %d attempts!\n",
1088			SAS_ADDR(device->sas_addr), TASK_RETRY);
1089	sas_free_task(task);
1090
1091	return res;
1092}
1093
1094static int sas_execute_ssp_tmf(struct domain_device *device, u8 *lun,
1095			       struct sas_tmf_task *tmf)
1096{
1097	struct sas_ssp_task ssp_task;
1098
1099	if (!(device->tproto & SAS_PROTOCOL_SSP))
1100		return TMF_RESP_FUNC_ESUPP;
1101
1102	memcpy(ssp_task.LUN, lun, 8);
1103
1104	return sas_execute_tmf(device, &ssp_task, sizeof(ssp_task), -1, tmf);
1105}
1106
1107int sas_abort_task_set(struct domain_device *dev, u8 *lun)
1108{
1109	struct sas_tmf_task tmf_task = {
1110		.tmf = TMF_ABORT_TASK_SET,
1111	};
1112
1113	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1114}
1115EXPORT_SYMBOL_GPL(sas_abort_task_set);
1116
1117int sas_clear_task_set(struct domain_device *dev, u8 *lun)
1118{
1119	struct sas_tmf_task tmf_task = {
1120		.tmf = TMF_CLEAR_TASK_SET,
1121	};
1122
1123	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1124}
1125EXPORT_SYMBOL_GPL(sas_clear_task_set);
1126
1127int sas_lu_reset(struct domain_device *dev, u8 *lun)
1128{
1129	struct sas_tmf_task tmf_task = {
1130		.tmf = TMF_LU_RESET,
1131	};
1132
1133	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1134}
1135EXPORT_SYMBOL_GPL(sas_lu_reset);
1136
1137int sas_query_task(struct sas_task *task, u16 tag)
1138{
1139	struct sas_tmf_task tmf_task = {
1140		.tmf = TMF_QUERY_TASK,
1141		.tag_of_task_to_be_managed = tag,
1142	};
1143	struct scsi_cmnd *cmnd = task->uldd_task;
1144	struct domain_device *dev = task->dev;
1145	struct scsi_lun lun;
1146
1147	int_to_scsilun(cmnd->device->lun, &lun);
1148
1149	return sas_execute_ssp_tmf(dev, lun.scsi_lun, &tmf_task);
1150}
1151EXPORT_SYMBOL_GPL(sas_query_task);
1152
1153int sas_abort_task(struct sas_task *task, u16 tag)
1154{
1155	struct sas_tmf_task tmf_task = {
1156		.tmf = TMF_ABORT_TASK,
1157		.tag_of_task_to_be_managed = tag,
1158	};
1159	struct scsi_cmnd *cmnd = task->uldd_task;
1160	struct domain_device *dev = task->dev;
1161	struct scsi_lun lun;
1162
1163	int_to_scsilun(cmnd->device->lun, &lun);
1164
1165	return sas_execute_ssp_tmf(dev, lun.scsi_lun, &tmf_task);
1166}
1167EXPORT_SYMBOL_GPL(sas_abort_task);
1168
1169/*
1170 * Tell an upper layer that it needs to initiate an abort for a given task.
1171 * This should only ever be called by an LLDD.
1172 */
1173void sas_task_abort(struct sas_task *task)
1174{
1175	struct scsi_cmnd *sc = task->uldd_task;
1176
1177	/* Escape for libsas internal commands */
1178	if (!sc) {
1179		struct sas_task_slow *slow = task->slow_task;
1180
1181		if (!slow)
1182			return;
1183		if (!del_timer(&slow->timer))
1184			return;
1185		slow->timer.function(&slow->timer);
1186		return;
1187	}
1188
1189	if (dev_is_sata(task->dev))
1190		sas_ata_task_abort(task);
1191	else
1192		blk_abort_request(scsi_cmd_to_rq(sc));
1193}
1194EXPORT_SYMBOL_GPL(sas_task_abort);
1195
1196int sas_slave_alloc(struct scsi_device *sdev)
1197{
1198	if (dev_is_sata(sdev_to_domain_dev(sdev)) && sdev->lun)
1199		return -ENXIO;
1200
1201	return 0;
1202}
1203EXPORT_SYMBOL_GPL(sas_slave_alloc);
1204
1205void sas_target_destroy(struct scsi_target *starget)
1206{
1207	struct domain_device *found_dev = starget->hostdata;
1208
1209	if (!found_dev)
1210		return;
1211
1212	starget->hostdata = NULL;
1213	sas_put_device(found_dev);
1214}
1215EXPORT_SYMBOL_GPL(sas_target_destroy);
1216
1217#define SAS_STRING_ADDR_SIZE	16
1218
1219int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
1220{
1221	int res;
1222	const struct firmware *fw;
1223
1224	res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
1225	if (res)
1226		return res;
1227
1228	if (fw->size < SAS_STRING_ADDR_SIZE) {
1229		res = -ENODEV;
1230		goto out;
1231	}
1232
1233	res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
1234	if (res)
1235		goto out;
1236
1237out:
1238	release_firmware(fw);
1239	return res;
1240}
1241EXPORT_SYMBOL_GPL(sas_request_addr);
1242
1243