xref: /linux/drivers/scsi/libsas/sas_scsi_host.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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 */
37 static 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 
99 static 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 
129 static 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 
160 int 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 
189 out_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;
197 out_done:
198 	scsi_done(cmd);
199 	return 0;
200 }
201 EXPORT_SYMBOL_GPL(sas_queuecommand);
202 
203 static 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 
230 static 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 
241 static 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 
254 static 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 
268 enum 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 
276 static 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 
324 static 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 
353 static 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 */
369 struct 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 }
387 EXPORT_SYMBOL_GPL(sas_get_local_phy);
388 
389 static 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 
425 int 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 }
454 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
455 
456 /* Attempt to send a LUN reset message to a device */
457 int 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 }
479 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
480 
481 int 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 }
501 EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
502 
503 /* Try to reset a device */
504 static 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 
516 try_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 
523 static 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 
656 static 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 
690 void 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 
697 retry:
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 
727 out:
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 
751 int 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 }
760 EXPORT_SYMBOL_GPL(sas_ioctl);
761 
762 struct 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 
791 int 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 }
803 EXPORT_SYMBOL_GPL(sas_target_alloc);
804 
805 #define SAS_DEF_QD 256
806 
807 int sas_device_configure(struct scsi_device *scsi_dev,
808 		struct queue_limits *lim)
809 {
810 	struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
811 
812 	BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
813 
814 	if (dev_is_sata(dev)) {
815 		ata_sas_device_configure(scsi_dev, lim, dev->sata_dev.ap);
816 		return 0;
817 	}
818 
819 	sas_read_port_mode_page(scsi_dev);
820 
821 	if (scsi_dev->tagged_supported) {
822 		scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
823 	} else {
824 		pr_notice("device %016llx, LUN 0x%llx doesn't support TCQ\n",
825 			  SAS_ADDR(dev->sas_addr), scsi_dev->lun);
826 		scsi_change_queue_depth(scsi_dev, 1);
827 	}
828 
829 	scsi_dev->allow_restart = 1;
830 
831 	return 0;
832 }
833 EXPORT_SYMBOL_GPL(sas_device_configure);
834 
835 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
836 {
837 	struct domain_device *dev = sdev_to_domain_dev(sdev);
838 
839 	if (dev_is_sata(dev))
840 		return ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
841 
842 	if (!sdev->tagged_supported)
843 		depth = 1;
844 	return scsi_change_queue_depth(sdev, depth);
845 }
846 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
847 
848 int sas_bios_param(struct scsi_device *scsi_dev,
849 			  struct block_device *bdev,
850 			  sector_t capacity, int *hsc)
851 {
852 	hsc[0] = 255;
853 	hsc[1] = 63;
854 	sector_div(capacity, 255*63);
855 	hsc[2] = capacity;
856 
857 	return 0;
858 }
859 EXPORT_SYMBOL_GPL(sas_bios_param);
860 
861 void sas_task_internal_done(struct sas_task *task)
862 {
863 	del_timer(&task->slow_task->timer);
864 	complete(&task->slow_task->completion);
865 }
866 
867 void sas_task_internal_timedout(struct timer_list *t)
868 {
869 	struct sas_task_slow *slow = from_timer(slow, t, timer);
870 	struct sas_task *task = slow->task;
871 	bool is_completed = true;
872 	unsigned long flags;
873 
874 	spin_lock_irqsave(&task->task_state_lock, flags);
875 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
876 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
877 		is_completed = false;
878 	}
879 	spin_unlock_irqrestore(&task->task_state_lock, flags);
880 
881 	if (!is_completed)
882 		complete(&task->slow_task->completion);
883 }
884 
885 #define TASK_TIMEOUT			(20 * HZ)
886 #define TASK_RETRY			3
887 
888 static int sas_execute_internal_abort(struct domain_device *device,
889 				      enum sas_internal_abort type, u16 tag,
890 				      unsigned int qid, void *data)
891 {
892 	struct sas_ha_struct *ha = device->port->ha;
893 	struct sas_internal *i = to_sas_internal(ha->shost->transportt);
894 	struct sas_task *task = NULL;
895 	int res, retry;
896 
897 	for (retry = 0; retry < TASK_RETRY; retry++) {
898 		task = sas_alloc_slow_task(GFP_KERNEL);
899 		if (!task)
900 			return -ENOMEM;
901 
902 		task->dev = device;
903 		task->task_proto = SAS_PROTOCOL_INTERNAL_ABORT;
904 		task->task_done = sas_task_internal_done;
905 		task->slow_task->timer.function = sas_task_internal_timedout;
906 		task->slow_task->timer.expires = jiffies + TASK_TIMEOUT;
907 		add_timer(&task->slow_task->timer);
908 
909 		task->abort_task.tag = tag;
910 		task->abort_task.type = type;
911 		task->abort_task.qid = qid;
912 
913 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
914 		if (res) {
915 			del_timer_sync(&task->slow_task->timer);
916 			pr_err("Executing internal abort failed %016llx (%d)\n",
917 			       SAS_ADDR(device->sas_addr), res);
918 			break;
919 		}
920 
921 		wait_for_completion(&task->slow_task->completion);
922 		res = TMF_RESP_FUNC_FAILED;
923 
924 		/* Even if the internal abort timed out, return direct. */
925 		if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
926 			bool quit = true;
927 
928 			if (i->dft->lldd_abort_timeout)
929 				quit = i->dft->lldd_abort_timeout(task, data);
930 			else
931 				pr_err("Internal abort: timeout %016llx\n",
932 				       SAS_ADDR(device->sas_addr));
933 			res = -EIO;
934 			if (quit)
935 				break;
936 		}
937 
938 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
939 			task->task_status.stat == SAS_SAM_STAT_GOOD) {
940 			res = TMF_RESP_FUNC_COMPLETE;
941 			break;
942 		}
943 
944 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
945 			task->task_status.stat == TMF_RESP_FUNC_SUCC) {
946 			res = TMF_RESP_FUNC_SUCC;
947 			break;
948 		}
949 
950 		pr_err("Internal abort: task to dev %016llx response: 0x%x status 0x%x\n",
951 		       SAS_ADDR(device->sas_addr), task->task_status.resp,
952 		       task->task_status.stat);
953 		sas_free_task(task);
954 		task = NULL;
955 	}
956 	BUG_ON(retry == TASK_RETRY && task != NULL);
957 	sas_free_task(task);
958 	return res;
959 }
960 
961 int sas_execute_internal_abort_single(struct domain_device *device, u16 tag,
962 				      unsigned int qid, void *data)
963 {
964 	return sas_execute_internal_abort(device, SAS_INTERNAL_ABORT_SINGLE,
965 					  tag, qid, data);
966 }
967 EXPORT_SYMBOL_GPL(sas_execute_internal_abort_single);
968 
969 int sas_execute_internal_abort_dev(struct domain_device *device,
970 				   unsigned int qid, void *data)
971 {
972 	return sas_execute_internal_abort(device, SAS_INTERNAL_ABORT_DEV,
973 					  SCSI_NO_TAG, qid, data);
974 }
975 EXPORT_SYMBOL_GPL(sas_execute_internal_abort_dev);
976 
977 int sas_execute_tmf(struct domain_device *device, void *parameter,
978 		    int para_len, int force_phy_id,
979 		    struct sas_tmf_task *tmf)
980 {
981 	struct sas_task *task;
982 	struct sas_internal *i =
983 		to_sas_internal(device->port->ha->shost->transportt);
984 	int res, retry;
985 
986 	for (retry = 0; retry < TASK_RETRY; retry++) {
987 		task = sas_alloc_slow_task(GFP_KERNEL);
988 		if (!task)
989 			return -ENOMEM;
990 
991 		task->dev = device;
992 		task->task_proto = device->tproto;
993 
994 		if (dev_is_sata(device)) {
995 			task->ata_task.device_control_reg_update = 1;
996 			if (force_phy_id >= 0) {
997 				task->ata_task.force_phy = true;
998 				task->ata_task.force_phy_id = force_phy_id;
999 			}
1000 			memcpy(&task->ata_task.fis, parameter, para_len);
1001 		} else {
1002 			memcpy(&task->ssp_task, parameter, para_len);
1003 		}
1004 
1005 		task->task_done = sas_task_internal_done;
1006 		task->tmf = tmf;
1007 
1008 		task->slow_task->timer.function = sas_task_internal_timedout;
1009 		task->slow_task->timer.expires = jiffies + TASK_TIMEOUT;
1010 		add_timer(&task->slow_task->timer);
1011 
1012 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
1013 		if (res) {
1014 			del_timer_sync(&task->slow_task->timer);
1015 			pr_err("executing TMF task failed %016llx (%d)\n",
1016 			       SAS_ADDR(device->sas_addr), res);
1017 			break;
1018 		}
1019 
1020 		wait_for_completion(&task->slow_task->completion);
1021 
1022 		if (i->dft->lldd_tmf_exec_complete)
1023 			i->dft->lldd_tmf_exec_complete(device);
1024 
1025 		res = TMF_RESP_FUNC_FAILED;
1026 
1027 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
1028 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
1029 				pr_err("TMF task timeout for %016llx and not done\n",
1030 				       SAS_ADDR(device->sas_addr));
1031 				if (i->dft->lldd_tmf_aborted)
1032 					i->dft->lldd_tmf_aborted(task);
1033 				break;
1034 			}
1035 			pr_warn("TMF task timeout for %016llx and done\n",
1036 				SAS_ADDR(device->sas_addr));
1037 		}
1038 
1039 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1040 		    task->task_status.stat == TMF_RESP_FUNC_COMPLETE) {
1041 			res = TMF_RESP_FUNC_COMPLETE;
1042 			break;
1043 		}
1044 
1045 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1046 		    task->task_status.stat == TMF_RESP_FUNC_SUCC) {
1047 			res = TMF_RESP_FUNC_SUCC;
1048 			break;
1049 		}
1050 
1051 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1052 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
1053 			/* no error, but return the number of bytes of
1054 			 * underrun
1055 			 */
1056 			pr_warn("TMF task to dev %016llx resp: 0x%x sts 0x%x underrun\n",
1057 				SAS_ADDR(device->sas_addr),
1058 				task->task_status.resp,
1059 				task->task_status.stat);
1060 			res = task->task_status.residual;
1061 			break;
1062 		}
1063 
1064 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1065 		    task->task_status.stat == SAS_DATA_OVERRUN) {
1066 			pr_warn("TMF task blocked task error %016llx\n",
1067 				SAS_ADDR(device->sas_addr));
1068 			res = -EMSGSIZE;
1069 			break;
1070 		}
1071 
1072 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
1073 		    task->task_status.stat == SAS_OPEN_REJECT) {
1074 			pr_warn("TMF task open reject failed  %016llx\n",
1075 				SAS_ADDR(device->sas_addr));
1076 			res = -EIO;
1077 		} else {
1078 			pr_warn("TMF task to dev %016llx resp: 0x%x status 0x%x\n",
1079 				SAS_ADDR(device->sas_addr),
1080 				task->task_status.resp,
1081 				task->task_status.stat);
1082 		}
1083 		sas_free_task(task);
1084 		task = NULL;
1085 	}
1086 
1087 	if (retry == TASK_RETRY)
1088 		pr_warn("executing TMF for %016llx failed after %d attempts!\n",
1089 			SAS_ADDR(device->sas_addr), TASK_RETRY);
1090 	sas_free_task(task);
1091 
1092 	return res;
1093 }
1094 
1095 static int sas_execute_ssp_tmf(struct domain_device *device, u8 *lun,
1096 			       struct sas_tmf_task *tmf)
1097 {
1098 	struct sas_ssp_task ssp_task;
1099 
1100 	if (!(device->tproto & SAS_PROTOCOL_SSP))
1101 		return TMF_RESP_FUNC_ESUPP;
1102 
1103 	memcpy(ssp_task.LUN, lun, 8);
1104 
1105 	return sas_execute_tmf(device, &ssp_task, sizeof(ssp_task), -1, tmf);
1106 }
1107 
1108 int sas_abort_task_set(struct domain_device *dev, u8 *lun)
1109 {
1110 	struct sas_tmf_task tmf_task = {
1111 		.tmf = TMF_ABORT_TASK_SET,
1112 	};
1113 
1114 	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1115 }
1116 EXPORT_SYMBOL_GPL(sas_abort_task_set);
1117 
1118 int sas_clear_task_set(struct domain_device *dev, u8 *lun)
1119 {
1120 	struct sas_tmf_task tmf_task = {
1121 		.tmf = TMF_CLEAR_TASK_SET,
1122 	};
1123 
1124 	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1125 }
1126 EXPORT_SYMBOL_GPL(sas_clear_task_set);
1127 
1128 int sas_lu_reset(struct domain_device *dev, u8 *lun)
1129 {
1130 	struct sas_tmf_task tmf_task = {
1131 		.tmf = TMF_LU_RESET,
1132 	};
1133 
1134 	return sas_execute_ssp_tmf(dev, lun, &tmf_task);
1135 }
1136 EXPORT_SYMBOL_GPL(sas_lu_reset);
1137 
1138 int sas_query_task(struct sas_task *task, u16 tag)
1139 {
1140 	struct sas_tmf_task tmf_task = {
1141 		.tmf = TMF_QUERY_TASK,
1142 		.tag_of_task_to_be_managed = tag,
1143 	};
1144 	struct scsi_cmnd *cmnd = task->uldd_task;
1145 	struct domain_device *dev = task->dev;
1146 	struct scsi_lun lun;
1147 
1148 	int_to_scsilun(cmnd->device->lun, &lun);
1149 
1150 	return sas_execute_ssp_tmf(dev, lun.scsi_lun, &tmf_task);
1151 }
1152 EXPORT_SYMBOL_GPL(sas_query_task);
1153 
1154 int sas_abort_task(struct sas_task *task, u16 tag)
1155 {
1156 	struct sas_tmf_task tmf_task = {
1157 		.tmf = TMF_ABORT_TASK,
1158 		.tag_of_task_to_be_managed = tag,
1159 	};
1160 	struct scsi_cmnd *cmnd = task->uldd_task;
1161 	struct domain_device *dev = task->dev;
1162 	struct scsi_lun lun;
1163 
1164 	int_to_scsilun(cmnd->device->lun, &lun);
1165 
1166 	return sas_execute_ssp_tmf(dev, lun.scsi_lun, &tmf_task);
1167 }
1168 EXPORT_SYMBOL_GPL(sas_abort_task);
1169 
1170 /*
1171  * Tell an upper layer that it needs to initiate an abort for a given task.
1172  * This should only ever be called by an LLDD.
1173  */
1174 void sas_task_abort(struct sas_task *task)
1175 {
1176 	struct scsi_cmnd *sc = task->uldd_task;
1177 
1178 	/* Escape for libsas internal commands */
1179 	if (!sc) {
1180 		struct sas_task_slow *slow = task->slow_task;
1181 
1182 		if (!slow)
1183 			return;
1184 		if (!del_timer(&slow->timer))
1185 			return;
1186 		slow->timer.function(&slow->timer);
1187 		return;
1188 	}
1189 
1190 	if (dev_is_sata(task->dev))
1191 		sas_ata_task_abort(task);
1192 	else
1193 		blk_abort_request(scsi_cmd_to_rq(sc));
1194 }
1195 EXPORT_SYMBOL_GPL(sas_task_abort);
1196 
1197 int sas_slave_alloc(struct scsi_device *sdev)
1198 {
1199 	if (dev_is_sata(sdev_to_domain_dev(sdev)) && sdev->lun)
1200 		return -ENXIO;
1201 
1202 	return 0;
1203 }
1204 EXPORT_SYMBOL_GPL(sas_slave_alloc);
1205 
1206 void sas_target_destroy(struct scsi_target *starget)
1207 {
1208 	struct domain_device *found_dev = starget->hostdata;
1209 
1210 	if (!found_dev)
1211 		return;
1212 
1213 	starget->hostdata = NULL;
1214 	sas_put_device(found_dev);
1215 }
1216 EXPORT_SYMBOL_GPL(sas_target_destroy);
1217 
1218 #define SAS_STRING_ADDR_SIZE	16
1219 
1220 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
1221 {
1222 	int res;
1223 	const struct firmware *fw;
1224 
1225 	res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
1226 	if (res)
1227 		return res;
1228 
1229 	if (fw->size < SAS_STRING_ADDR_SIZE) {
1230 		res = -ENODEV;
1231 		goto out;
1232 	}
1233 
1234 	res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
1235 	if (res)
1236 		goto out;
1237 
1238 out:
1239 	release_firmware(fw);
1240 	return res;
1241 }
1242 EXPORT_SYMBOL_GPL(sas_request_addr);
1243 
1244