1 /*
2  * Serial Attached SCSI (SAS) class SCSI Host glue.
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
22  * USA
23  *
24  */
25 
26 #include <linux/kthread.h>
27 #include <linux/firmware.h>
28 #include <linux/export.h>
29 #include <linux/ctype.h>
30 
31 #include "sas_internal.h"
32 
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi_device.h>
35 #include <scsi/scsi_tcq.h>
36 #include <scsi/scsi.h>
37 #include <scsi/scsi_eh.h>
38 #include <scsi/scsi_transport.h>
39 #include <scsi/scsi_transport_sas.h>
40 #include <scsi/sas_ata.h>
41 #include "../scsi_sas_internal.h"
42 #include "../scsi_transport_api.h"
43 #include "../scsi_priv.h"
44 
45 #include <linux/err.h>
46 #include <linux/blkdev.h>
47 #include <linux/freezer.h>
48 #include <linux/gfp.h>
49 #include <linux/scatterlist.h>
50 #include <linux/libata.h>
51 
52 /* record final status and free the task */
sas_end_task(struct scsi_cmnd * sc,struct sas_task * task)53 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
54 {
55 	struct task_status_struct *ts = &task->task_status;
56 	int hs = 0, stat = 0;
57 
58 	if (ts->resp == SAS_TASK_UNDELIVERED) {
59 		/* transport error */
60 		hs = DID_NO_CONNECT;
61 	} else { /* ts->resp == SAS_TASK_COMPLETE */
62 		/* task delivered, what happened afterwards? */
63 		switch (ts->stat) {
64 		case SAS_DEV_NO_RESPONSE:
65 		case SAS_INTERRUPTED:
66 		case SAS_PHY_DOWN:
67 		case SAS_NAK_R_ERR:
68 		case SAS_OPEN_TO:
69 			hs = DID_NO_CONNECT;
70 			break;
71 		case SAS_DATA_UNDERRUN:
72 			scsi_set_resid(sc, ts->residual);
73 			if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
74 				hs = DID_ERROR;
75 			break;
76 		case SAS_DATA_OVERRUN:
77 			hs = DID_ERROR;
78 			break;
79 		case SAS_QUEUE_FULL:
80 			hs = DID_SOFT_ERROR; /* retry */
81 			break;
82 		case SAS_DEVICE_UNKNOWN:
83 			hs = DID_BAD_TARGET;
84 			break;
85 		case SAS_SG_ERR:
86 			hs = DID_PARITY;
87 			break;
88 		case SAS_OPEN_REJECT:
89 			if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
90 				hs = DID_SOFT_ERROR; /* retry */
91 			else
92 				hs = DID_ERROR;
93 			break;
94 		case SAS_PROTO_RESPONSE:
95 			SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
96 				    "task; please report this\n",
97 				    task->dev->port->ha->sas_ha_name);
98 			break;
99 		case SAS_ABORTED_TASK:
100 			hs = DID_ABORT;
101 			break;
102 		case SAM_STAT_CHECK_CONDITION:
103 			memcpy(sc->sense_buffer, ts->buf,
104 			       min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
105 			stat = SAM_STAT_CHECK_CONDITION;
106 			break;
107 		default:
108 			stat = ts->stat;
109 			break;
110 		}
111 	}
112 
113 	sc->result = (hs << 16) | stat;
114 	ASSIGN_SAS_TASK(sc, NULL);
115 	list_del_init(&task->list);
116 	sas_free_task(task);
117 }
118 
sas_scsi_task_done(struct sas_task * task)119 static void sas_scsi_task_done(struct sas_task *task)
120 {
121 	struct scsi_cmnd *sc = task->uldd_task;
122 	struct domain_device *dev = task->dev;
123 	struct sas_ha_struct *ha = dev->port->ha;
124 	unsigned long flags;
125 
126 	spin_lock_irqsave(&dev->done_lock, flags);
127 	if (test_bit(SAS_HA_FROZEN, &ha->state))
128 		task = NULL;
129 	else
130 		ASSIGN_SAS_TASK(sc, NULL);
131 	spin_unlock_irqrestore(&dev->done_lock, flags);
132 
133 	if (unlikely(!task)) {
134 		/* task will be completed by the error handler */
135 		SAS_DPRINTK("task done but aborted\n");
136 		return;
137 	}
138 
139 	if (unlikely(!sc)) {
140 		SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
141 		list_del_init(&task->list);
142 		sas_free_task(task);
143 		return;
144 	}
145 
146 	sas_end_task(sc, task);
147 	sc->scsi_done(sc);
148 }
149 
sas_create_task(struct scsi_cmnd * cmd,struct domain_device * dev,gfp_t gfp_flags)150 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
151 					       struct domain_device *dev,
152 					       gfp_t gfp_flags)
153 {
154 	struct sas_task *task = sas_alloc_task(gfp_flags);
155 	struct scsi_lun lun;
156 
157 	if (!task)
158 		return NULL;
159 
160 	task->uldd_task = cmd;
161 	ASSIGN_SAS_TASK(cmd, task);
162 
163 	task->dev = dev;
164 	task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
165 
166 	task->ssp_task.retry_count = 1;
167 	int_to_scsilun(cmd->device->lun, &lun);
168 	memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
169 	task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
170 	memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
171 
172 	task->scatter = scsi_sglist(cmd);
173 	task->num_scatter = scsi_sg_count(cmd);
174 	task->total_xfer_len = scsi_bufflen(cmd);
175 	task->data_dir = cmd->sc_data_direction;
176 
177 	task->task_done = sas_scsi_task_done;
178 
179 	return task;
180 }
181 
sas_queue_up(struct sas_task * task)182 int sas_queue_up(struct sas_task *task)
183 {
184 	struct sas_ha_struct *sas_ha = task->dev->port->ha;
185 	struct scsi_core *core = &sas_ha->core;
186 	unsigned long flags;
187 	LIST_HEAD(list);
188 
189 	spin_lock_irqsave(&core->task_queue_lock, flags);
190 	if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
191 		spin_unlock_irqrestore(&core->task_queue_lock, flags);
192 		return -SAS_QUEUE_FULL;
193 	}
194 	list_add_tail(&task->list, &core->task_queue);
195 	core->task_queue_size += 1;
196 	spin_unlock_irqrestore(&core->task_queue_lock, flags);
197 	wake_up_process(core->queue_thread);
198 
199 	return 0;
200 }
201 
sas_queuecommand(struct Scsi_Host * host,struct scsi_cmnd * cmd)202 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
203 {
204 	struct sas_internal *i = to_sas_internal(host->transportt);
205 	struct domain_device *dev = cmd_to_domain_dev(cmd);
206 	struct sas_ha_struct *sas_ha = dev->port->ha;
207 	struct sas_task *task;
208 	int res = 0;
209 
210 	/* If the device fell off, no sense in issuing commands */
211 	if (test_bit(SAS_DEV_GONE, &dev->state)) {
212 		cmd->result = DID_BAD_TARGET << 16;
213 		goto out_done;
214 	}
215 
216 	if (dev_is_sata(dev)) {
217 		spin_lock_irq(dev->sata_dev.ap->lock);
218 		res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
219 		spin_unlock_irq(dev->sata_dev.ap->lock);
220 		return res;
221 	}
222 
223 	task = sas_create_task(cmd, dev, GFP_ATOMIC);
224 	if (!task)
225 		return SCSI_MLQUEUE_HOST_BUSY;
226 
227 	/* Queue up, Direct Mode or Task Collector Mode. */
228 	if (sas_ha->lldd_max_execute_num < 2)
229 		res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
230 	else
231 		res = sas_queue_up(task);
232 
233 	if (res)
234 		goto out_free_task;
235 	return 0;
236 
237 out_free_task:
238 	SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
239 	ASSIGN_SAS_TASK(cmd, NULL);
240 	sas_free_task(task);
241 	if (res == -SAS_QUEUE_FULL)
242 		cmd->result = DID_SOFT_ERROR << 16; /* retry */
243 	else
244 		cmd->result = DID_ERROR << 16;
245 out_done:
246 	cmd->scsi_done(cmd);
247 	return 0;
248 }
249 
sas_eh_finish_cmd(struct scsi_cmnd * cmd)250 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
251 {
252 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
253 	struct sas_task *task = TO_SAS_TASK(cmd);
254 
255 	/* At this point, we only get called following an actual abort
256 	 * of the task, so we should be guaranteed not to be racing with
257 	 * any completions from the LLD.  Task is freed after this.
258 	 */
259 	sas_end_task(cmd, task);
260 
261 	/* now finish the command and move it on to the error
262 	 * handler done list, this also takes it off the
263 	 * error handler pending list.
264 	 */
265 	scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
266 }
267 
sas_eh_defer_cmd(struct scsi_cmnd * cmd)268 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
269 {
270 	struct domain_device *dev = cmd_to_domain_dev(cmd);
271 	struct sas_ha_struct *ha = dev->port->ha;
272 	struct sas_task *task = TO_SAS_TASK(cmd);
273 
274 	if (!dev_is_sata(dev)) {
275 		sas_eh_finish_cmd(cmd);
276 		return;
277 	}
278 
279 	/* report the timeout to libata */
280 	sas_end_task(cmd, task);
281 	list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
282 }
283 
sas_scsi_clear_queue_lu(struct list_head * error_q,struct scsi_cmnd * my_cmd)284 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
285 {
286 	struct scsi_cmnd *cmd, *n;
287 
288 	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
289 		if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
290 		    cmd->device->lun == my_cmd->device->lun)
291 			sas_eh_defer_cmd(cmd);
292 	}
293 }
294 
sas_scsi_clear_queue_I_T(struct list_head * error_q,struct domain_device * dev)295 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
296 				     struct domain_device *dev)
297 {
298 	struct scsi_cmnd *cmd, *n;
299 
300 	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
301 		struct domain_device *x = cmd_to_domain_dev(cmd);
302 
303 		if (x == dev)
304 			sas_eh_finish_cmd(cmd);
305 	}
306 }
307 
sas_scsi_clear_queue_port(struct list_head * error_q,struct asd_sas_port * port)308 static void sas_scsi_clear_queue_port(struct list_head *error_q,
309 				      struct asd_sas_port *port)
310 {
311 	struct scsi_cmnd *cmd, *n;
312 
313 	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
314 		struct domain_device *dev = cmd_to_domain_dev(cmd);
315 		struct asd_sas_port *x = dev->port;
316 
317 		if (x == port)
318 			sas_eh_finish_cmd(cmd);
319 	}
320 }
321 
322 enum task_disposition {
323 	TASK_IS_DONE,
324 	TASK_IS_ABORTED,
325 	TASK_IS_AT_LU,
326 	TASK_IS_NOT_AT_HA,
327 	TASK_IS_NOT_AT_LU,
328 	TASK_ABORT_FAILED,
329 };
330 
sas_scsi_find_task(struct sas_task * task)331 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
332 {
333 	struct sas_ha_struct *ha = task->dev->port->ha;
334 	unsigned long flags;
335 	int i, res;
336 	struct sas_internal *si =
337 		to_sas_internal(task->dev->port->ha->core.shost->transportt);
338 
339 	if (ha->lldd_max_execute_num > 1) {
340 		struct scsi_core *core = &ha->core;
341 		struct sas_task *t, *n;
342 
343 		mutex_lock(&core->task_queue_flush);
344 		spin_lock_irqsave(&core->task_queue_lock, flags);
345 		list_for_each_entry_safe(t, n, &core->task_queue, list)
346 			if (task == t) {
347 				list_del_init(&t->list);
348 				break;
349 			}
350 		spin_unlock_irqrestore(&core->task_queue_lock, flags);
351 		mutex_unlock(&core->task_queue_flush);
352 
353 		if (task == t)
354 			return TASK_IS_NOT_AT_HA;
355 	}
356 
357 	for (i = 0; i < 5; i++) {
358 		SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, task);
359 		res = si->dft->lldd_abort_task(task);
360 
361 		spin_lock_irqsave(&task->task_state_lock, flags);
362 		if (task->task_state_flags & SAS_TASK_STATE_DONE) {
363 			spin_unlock_irqrestore(&task->task_state_lock, flags);
364 			SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
365 				    task);
366 			return TASK_IS_DONE;
367 		}
368 		spin_unlock_irqrestore(&task->task_state_lock, flags);
369 
370 		if (res == TMF_RESP_FUNC_COMPLETE) {
371 			SAS_DPRINTK("%s: task 0x%p is aborted\n",
372 				    __func__, task);
373 			return TASK_IS_ABORTED;
374 		} else if (si->dft->lldd_query_task) {
375 			SAS_DPRINTK("%s: querying task 0x%p\n",
376 				    __func__, task);
377 			res = si->dft->lldd_query_task(task);
378 			switch (res) {
379 			case TMF_RESP_FUNC_SUCC:
380 				SAS_DPRINTK("%s: task 0x%p at LU\n",
381 					    __func__, task);
382 				return TASK_IS_AT_LU;
383 			case TMF_RESP_FUNC_COMPLETE:
384 				SAS_DPRINTK("%s: task 0x%p not at LU\n",
385 					    __func__, task);
386 				return TASK_IS_NOT_AT_LU;
387 			case TMF_RESP_FUNC_FAILED:
388                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
389                                                 __func__, task);
390                                 return TASK_ABORT_FAILED;
391                         }
392 
393 		}
394 	}
395 	return res;
396 }
397 
sas_recover_lu(struct domain_device * dev,struct scsi_cmnd * cmd)398 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
399 {
400 	int res = TMF_RESP_FUNC_FAILED;
401 	struct scsi_lun lun;
402 	struct sas_internal *i =
403 		to_sas_internal(dev->port->ha->core.shost->transportt);
404 
405 	int_to_scsilun(cmd->device->lun, &lun);
406 
407 	SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
408 		    SAS_ADDR(dev->sas_addr),
409 		    cmd->device->lun);
410 
411 	if (i->dft->lldd_abort_task_set)
412 		res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
413 
414 	if (res == TMF_RESP_FUNC_FAILED) {
415 		if (i->dft->lldd_clear_task_set)
416 			res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
417 	}
418 
419 	if (res == TMF_RESP_FUNC_FAILED) {
420 		if (i->dft->lldd_lu_reset)
421 			res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
422 	}
423 
424 	return res;
425 }
426 
sas_recover_I_T(struct domain_device * dev)427 static int sas_recover_I_T(struct domain_device *dev)
428 {
429 	int res = TMF_RESP_FUNC_FAILED;
430 	struct sas_internal *i =
431 		to_sas_internal(dev->port->ha->core.shost->transportt);
432 
433 	SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
434 		    SAS_ADDR(dev->sas_addr));
435 
436 	if (i->dft->lldd_I_T_nexus_reset)
437 		res = i->dft->lldd_I_T_nexus_reset(dev);
438 
439 	return res;
440 }
441 
442 /* take a reference on the last known good phy for this device */
sas_get_local_phy(struct domain_device * dev)443 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
444 {
445 	struct sas_ha_struct *ha = dev->port->ha;
446 	struct sas_phy *phy;
447 	unsigned long flags;
448 
449 	/* a published domain device always has a valid phy, it may be
450 	 * stale, but it is never NULL
451 	 */
452 	BUG_ON(!dev->phy);
453 
454 	spin_lock_irqsave(&ha->phy_port_lock, flags);
455 	phy = dev->phy;
456 	get_device(&phy->dev);
457 	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
458 
459 	return phy;
460 }
461 EXPORT_SYMBOL_GPL(sas_get_local_phy);
462 
463 /* Attempt to send a LUN reset message to a device */
sas_eh_device_reset_handler(struct scsi_cmnd * cmd)464 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
465 {
466 	struct domain_device *dev = cmd_to_domain_dev(cmd);
467 	struct sas_internal *i =
468 		to_sas_internal(dev->port->ha->core.shost->transportt);
469 	struct scsi_lun lun;
470 	int res;
471 
472 	int_to_scsilun(cmd->device->lun, &lun);
473 
474 	if (!i->dft->lldd_lu_reset)
475 		return FAILED;
476 
477 	res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
478 	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
479 		return SUCCESS;
480 
481 	return FAILED;
482 }
483 
484 /* Attempt to send a phy (bus) reset */
sas_eh_bus_reset_handler(struct scsi_cmnd * cmd)485 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
486 {
487 	struct domain_device *dev = cmd_to_domain_dev(cmd);
488 	struct sas_phy *phy = sas_get_local_phy(dev);
489 	int res;
490 
491 	res = sas_phy_reset(phy, 1);
492 	if (res)
493 		SAS_DPRINTK("Bus reset of %s failed 0x%x\n",
494 			    kobject_name(&phy->dev.kobj),
495 			    res);
496 	sas_put_local_phy(phy);
497 
498 	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
499 		return SUCCESS;
500 
501 	return FAILED;
502 }
503 
504 /* Try to reset a device */
try_to_reset_cmd_device(struct scsi_cmnd * cmd)505 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
506 {
507 	int res;
508 	struct Scsi_Host *shost = cmd->device->host;
509 
510 	if (!shost->hostt->eh_device_reset_handler)
511 		goto try_bus_reset;
512 
513 	res = shost->hostt->eh_device_reset_handler(cmd);
514 	if (res == SUCCESS)
515 		return res;
516 
517 try_bus_reset:
518 	if (shost->hostt->eh_bus_reset_handler)
519 		return shost->hostt->eh_bus_reset_handler(cmd);
520 
521 	return FAILED;
522 }
523 
sas_eh_handle_sas_errors(struct Scsi_Host * shost,struct list_head * work_q)524 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
525 {
526 	struct scsi_cmnd *cmd, *n;
527 	enum task_disposition res = TASK_IS_DONE;
528 	int tmf_resp, need_reset;
529 	struct sas_internal *i = to_sas_internal(shost->transportt);
530 	unsigned long flags;
531 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
532 	LIST_HEAD(done);
533 
534 	/* clean out any commands that won the completion vs eh race */
535 	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
536 		struct domain_device *dev = cmd_to_domain_dev(cmd);
537 		struct sas_task *task;
538 
539 		spin_lock_irqsave(&dev->done_lock, flags);
540 		/* by this point the lldd has either observed
541 		 * SAS_HA_FROZEN and is leaving the task alone, or has
542 		 * won the race with eh and decided to complete it
543 		 */
544 		task = TO_SAS_TASK(cmd);
545 		spin_unlock_irqrestore(&dev->done_lock, flags);
546 
547 		if (!task)
548 			list_move_tail(&cmd->eh_entry, &done);
549 	}
550 
551  Again:
552 	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
553 		struct sas_task *task = TO_SAS_TASK(cmd);
554 
555 		list_del_init(&cmd->eh_entry);
556 
557 		spin_lock_irqsave(&task->task_state_lock, flags);
558 		need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
559 		spin_unlock_irqrestore(&task->task_state_lock, flags);
560 
561 		if (need_reset) {
562 			SAS_DPRINTK("%s: task 0x%p requests reset\n",
563 				    __func__, task);
564 			goto reset;
565 		}
566 
567 		SAS_DPRINTK("trying to find task 0x%p\n", task);
568 		res = sas_scsi_find_task(task);
569 
570 		cmd->eh_eflags = 0;
571 
572 		switch (res) {
573 		case TASK_IS_NOT_AT_HA:
574 			SAS_DPRINTK("%s: task 0x%p is not at ha: %s\n",
575 				    __func__, task,
576 				    cmd->retries ? "retry" : "aborted");
577 			if (cmd->retries)
578 				cmd->retries--;
579 			sas_eh_finish_cmd(cmd);
580 			continue;
581 		case TASK_IS_DONE:
582 			SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
583 				    task);
584 			sas_eh_defer_cmd(cmd);
585 			continue;
586 		case TASK_IS_ABORTED:
587 			SAS_DPRINTK("%s: task 0x%p is aborted\n",
588 				    __func__, task);
589 			sas_eh_defer_cmd(cmd);
590 			continue;
591 		case TASK_IS_AT_LU:
592 			SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
593  reset:
594 			tmf_resp = sas_recover_lu(task->dev, cmd);
595 			if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
596 				SAS_DPRINTK("dev %016llx LU %x is "
597 					    "recovered\n",
598 					    SAS_ADDR(task->dev),
599 					    cmd->device->lun);
600 				sas_eh_defer_cmd(cmd);
601 				sas_scsi_clear_queue_lu(work_q, cmd);
602 				goto Again;
603 			}
604 			/* fallthrough */
605 		case TASK_IS_NOT_AT_LU:
606 		case TASK_ABORT_FAILED:
607 			SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
608 				    task);
609 			tmf_resp = sas_recover_I_T(task->dev);
610 			if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
611 			    tmf_resp == -ENODEV) {
612 				struct domain_device *dev = task->dev;
613 				SAS_DPRINTK("I_T %016llx recovered\n",
614 					    SAS_ADDR(task->dev->sas_addr));
615 				sas_eh_finish_cmd(cmd);
616 				sas_scsi_clear_queue_I_T(work_q, dev);
617 				goto Again;
618 			}
619 			/* Hammer time :-) */
620 			try_to_reset_cmd_device(cmd);
621 			if (i->dft->lldd_clear_nexus_port) {
622 				struct asd_sas_port *port = task->dev->port;
623 				SAS_DPRINTK("clearing nexus for port:%d\n",
624 					    port->id);
625 				res = i->dft->lldd_clear_nexus_port(port);
626 				if (res == TMF_RESP_FUNC_COMPLETE) {
627 					SAS_DPRINTK("clear nexus port:%d "
628 						    "succeeded\n", port->id);
629 					sas_eh_finish_cmd(cmd);
630 					sas_scsi_clear_queue_port(work_q,
631 								  port);
632 					goto Again;
633 				}
634 			}
635 			if (i->dft->lldd_clear_nexus_ha) {
636 				SAS_DPRINTK("clear nexus ha\n");
637 				res = i->dft->lldd_clear_nexus_ha(ha);
638 				if (res == TMF_RESP_FUNC_COMPLETE) {
639 					SAS_DPRINTK("clear nexus ha "
640 						    "succeeded\n");
641 					sas_eh_finish_cmd(cmd);
642 					goto clear_q;
643 				}
644 			}
645 			/* If we are here -- this means that no amount
646 			 * of effort could recover from errors.  Quite
647 			 * possibly the HA just disappeared.
648 			 */
649 			SAS_DPRINTK("error from  device %llx, LUN %x "
650 				    "couldn't be recovered in any way\n",
651 				    SAS_ADDR(task->dev->sas_addr),
652 				    cmd->device->lun);
653 
654 			sas_eh_finish_cmd(cmd);
655 			goto clear_q;
656 		}
657 	}
658  out:
659 	list_splice_tail(&done, work_q);
660 	list_splice_tail_init(&ha->eh_ata_q, work_q);
661 	return;
662 
663  clear_q:
664 	SAS_DPRINTK("--- Exit %s -- clear_q\n", __func__);
665 	list_for_each_entry_safe(cmd, n, work_q, eh_entry)
666 		sas_eh_finish_cmd(cmd);
667 	goto out;
668 }
669 
sas_scsi_recover_host(struct Scsi_Host * shost)670 void sas_scsi_recover_host(struct Scsi_Host *shost)
671 {
672 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
673 	unsigned long flags;
674 	LIST_HEAD(eh_work_q);
675 
676 	spin_lock_irqsave(shost->host_lock, flags);
677 	list_splice_init(&shost->eh_cmd_q, &eh_work_q);
678 	shost->host_eh_scheduled = 0;
679 	spin_unlock_irqrestore(shost->host_lock, flags);
680 
681 	SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
682 		    __func__, shost->host_busy, shost->host_failed);
683 	/*
684 	 * Deal with commands that still have SAS tasks (i.e. they didn't
685 	 * complete via the normal sas_task completion mechanism),
686 	 * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
687 	 */
688 	set_bit(SAS_HA_FROZEN, &ha->state);
689 	sas_eh_handle_sas_errors(shost, &eh_work_q);
690 	clear_bit(SAS_HA_FROZEN, &ha->state);
691 	if (list_empty(&eh_work_q))
692 		goto out;
693 
694 	/*
695 	 * Now deal with SCSI commands that completed ok but have a an error
696 	 * code (and hopefully sense data) attached.  This is roughly what
697 	 * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
698 	 * command we see here has no sas_task and is thus unknown to the HA.
699 	 */
700 	sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
701 	if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
702 		scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
703 
704 out:
705 	if (ha->lldd_max_execute_num > 1)
706 		wake_up_process(ha->core.queue_thread);
707 
708 	/* now link into libata eh --- if we have any ata devices */
709 	sas_ata_strategy_handler(shost);
710 
711 	scsi_eh_flush_done_q(&ha->eh_done_q);
712 
713 	SAS_DPRINTK("--- Exit %s: busy: %d failed: %d\n",
714 		    __func__, shost->host_busy, shost->host_failed);
715 }
716 
sas_scsi_timed_out(struct scsi_cmnd * cmd)717 enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
718 {
719 	scmd_printk(KERN_DEBUG, cmd, "command %p timed out\n", cmd);
720 
721 	return BLK_EH_NOT_HANDLED;
722 }
723 
sas_ioctl(struct scsi_device * sdev,int cmd,void __user * arg)724 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
725 {
726 	struct domain_device *dev = sdev_to_domain_dev(sdev);
727 
728 	if (dev_is_sata(dev))
729 		return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
730 
731 	return -EINVAL;
732 }
733 
sas_find_dev_by_rphy(struct sas_rphy * rphy)734 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
735 {
736 	struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
737 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
738 	struct domain_device *found_dev = NULL;
739 	int i;
740 	unsigned long flags;
741 
742 	spin_lock_irqsave(&ha->phy_port_lock, flags);
743 	for (i = 0; i < ha->num_phys; i++) {
744 		struct asd_sas_port *port = ha->sas_port[i];
745 		struct domain_device *dev;
746 
747 		spin_lock(&port->dev_list_lock);
748 		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
749 			if (rphy == dev->rphy) {
750 				found_dev = dev;
751 				spin_unlock(&port->dev_list_lock);
752 				goto found;
753 			}
754 		}
755 		spin_unlock(&port->dev_list_lock);
756 	}
757  found:
758 	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
759 
760 	return found_dev;
761 }
762 
sas_target_alloc(struct scsi_target * starget)763 int sas_target_alloc(struct scsi_target *starget)
764 {
765 	struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
766 	struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
767 
768 	if (!found_dev)
769 		return -ENODEV;
770 
771 	kref_get(&found_dev->kref);
772 	starget->hostdata = found_dev;
773 	return 0;
774 }
775 
776 #define SAS_DEF_QD 256
777 
sas_slave_configure(struct scsi_device * scsi_dev)778 int sas_slave_configure(struct scsi_device *scsi_dev)
779 {
780 	struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
781 	struct sas_ha_struct *sas_ha;
782 
783 	BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
784 
785 	if (dev_is_sata(dev)) {
786 		ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
787 		return 0;
788 	}
789 
790 	sas_ha = dev->port->ha;
791 
792 	sas_read_port_mode_page(scsi_dev);
793 
794 	if (scsi_dev->tagged_supported) {
795 		scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
796 		scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
797 	} else {
798 		SAS_DPRINTK("device %llx, LUN %x doesn't support "
799 			    "TCQ\n", SAS_ADDR(dev->sas_addr),
800 			    scsi_dev->lun);
801 		scsi_dev->tagged_supported = 0;
802 		scsi_set_tag_type(scsi_dev, 0);
803 		scsi_deactivate_tcq(scsi_dev, 1);
804 	}
805 
806 	scsi_dev->allow_restart = 1;
807 
808 	return 0;
809 }
810 
sas_change_queue_depth(struct scsi_device * sdev,int depth,int reason)811 int sas_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
812 {
813 	struct domain_device *dev = sdev_to_domain_dev(sdev);
814 
815 	if (dev_is_sata(dev))
816 		return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth,
817 						reason);
818 
819 	switch (reason) {
820 	case SCSI_QDEPTH_DEFAULT:
821 	case SCSI_QDEPTH_RAMP_UP:
822 		if (!sdev->tagged_supported)
823 			depth = 1;
824 		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
825 		break;
826 	case SCSI_QDEPTH_QFULL:
827 		scsi_track_queue_full(sdev, depth);
828 		break;
829 	default:
830 		return -EOPNOTSUPP;
831 	}
832 
833 	return depth;
834 }
835 
sas_change_queue_type(struct scsi_device * scsi_dev,int qt)836 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
837 {
838 	struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
839 
840 	if (dev_is_sata(dev))
841 		return -EINVAL;
842 
843 	if (!scsi_dev->tagged_supported)
844 		return 0;
845 
846 	scsi_deactivate_tcq(scsi_dev, 1);
847 
848 	scsi_set_tag_type(scsi_dev, qt);
849 	scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
850 
851 	return qt;
852 }
853 
sas_bios_param(struct scsi_device * scsi_dev,struct block_device * bdev,sector_t capacity,int * hsc)854 int sas_bios_param(struct scsi_device *scsi_dev,
855 			  struct block_device *bdev,
856 			  sector_t capacity, int *hsc)
857 {
858 	hsc[0] = 255;
859 	hsc[1] = 63;
860 	sector_div(capacity, 255*63);
861 	hsc[2] = capacity;
862 
863 	return 0;
864 }
865 
866 /* ---------- Task Collector Thread implementation ---------- */
867 
sas_queue(struct sas_ha_struct * sas_ha)868 static void sas_queue(struct sas_ha_struct *sas_ha)
869 {
870 	struct scsi_core *core = &sas_ha->core;
871 	unsigned long flags;
872 	LIST_HEAD(q);
873 	int can_queue;
874 	int res;
875 	struct sas_internal *i = to_sas_internal(core->shost->transportt);
876 
877 	mutex_lock(&core->task_queue_flush);
878 	spin_lock_irqsave(&core->task_queue_lock, flags);
879 	while (!kthread_should_stop() &&
880 	       !list_empty(&core->task_queue) &&
881 	       !test_bit(SAS_HA_FROZEN, &sas_ha->state)) {
882 
883 		can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
884 		if (can_queue >= 0) {
885 			can_queue = core->task_queue_size;
886 			list_splice_init(&core->task_queue, &q);
887 		} else {
888 			struct list_head *a, *n;
889 
890 			can_queue = sas_ha->lldd_queue_size;
891 			list_for_each_safe(a, n, &core->task_queue) {
892 				list_move_tail(a, &q);
893 				if (--can_queue == 0)
894 					break;
895 			}
896 			can_queue = sas_ha->lldd_queue_size;
897 		}
898 		core->task_queue_size -= can_queue;
899 		spin_unlock_irqrestore(&core->task_queue_lock, flags);
900 		{
901 			struct sas_task *task = list_entry(q.next,
902 							   struct sas_task,
903 							   list);
904 			list_del_init(&q);
905 			res = i->dft->lldd_execute_task(task, can_queue,
906 							GFP_KERNEL);
907 			if (unlikely(res))
908 				__list_add(&q, task->list.prev, &task->list);
909 		}
910 		spin_lock_irqsave(&core->task_queue_lock, flags);
911 		if (res) {
912 			list_splice_init(&q, &core->task_queue); /*at head*/
913 			core->task_queue_size += can_queue;
914 		}
915 	}
916 	spin_unlock_irqrestore(&core->task_queue_lock, flags);
917 	mutex_unlock(&core->task_queue_flush);
918 }
919 
920 /**
921  * sas_queue_thread -- The Task Collector thread
922  * @_sas_ha: pointer to struct sas_ha
923  */
sas_queue_thread(void * _sas_ha)924 static int sas_queue_thread(void *_sas_ha)
925 {
926 	struct sas_ha_struct *sas_ha = _sas_ha;
927 
928 	while (1) {
929 		set_current_state(TASK_INTERRUPTIBLE);
930 		schedule();
931 		sas_queue(sas_ha);
932 		if (kthread_should_stop())
933 			break;
934 	}
935 
936 	return 0;
937 }
938 
sas_init_queue(struct sas_ha_struct * sas_ha)939 int sas_init_queue(struct sas_ha_struct *sas_ha)
940 {
941 	struct scsi_core *core = &sas_ha->core;
942 
943 	spin_lock_init(&core->task_queue_lock);
944 	mutex_init(&core->task_queue_flush);
945 	core->task_queue_size = 0;
946 	INIT_LIST_HEAD(&core->task_queue);
947 
948 	core->queue_thread = kthread_run(sas_queue_thread, sas_ha,
949 					 "sas_queue_%d", core->shost->host_no);
950 	if (IS_ERR(core->queue_thread))
951 		return PTR_ERR(core->queue_thread);
952 	return 0;
953 }
954 
sas_shutdown_queue(struct sas_ha_struct * sas_ha)955 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
956 {
957 	unsigned long flags;
958 	struct scsi_core *core = &sas_ha->core;
959 	struct sas_task *task, *n;
960 
961 	kthread_stop(core->queue_thread);
962 
963 	if (!list_empty(&core->task_queue))
964 		SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
965 			    SAS_ADDR(sas_ha->sas_addr));
966 
967 	spin_lock_irqsave(&core->task_queue_lock, flags);
968 	list_for_each_entry_safe(task, n, &core->task_queue, list) {
969 		struct scsi_cmnd *cmd = task->uldd_task;
970 
971 		list_del_init(&task->list);
972 
973 		ASSIGN_SAS_TASK(cmd, NULL);
974 		sas_free_task(task);
975 		cmd->result = DID_ABORT << 16;
976 		cmd->scsi_done(cmd);
977 	}
978 	spin_unlock_irqrestore(&core->task_queue_lock, flags);
979 }
980 
981 /*
982  * Tell an upper layer that it needs to initiate an abort for a given task.
983  * This should only ever be called by an LLDD.
984  */
sas_task_abort(struct sas_task * task)985 void sas_task_abort(struct sas_task *task)
986 {
987 	struct scsi_cmnd *sc = task->uldd_task;
988 
989 	/* Escape for libsas internal commands */
990 	if (!sc) {
991 		if (!del_timer(&task->timer))
992 			return;
993 		task->timer.function(task->timer.data);
994 		return;
995 	}
996 
997 	if (dev_is_sata(task->dev)) {
998 		sas_ata_task_abort(task);
999 	} else {
1000 		struct request_queue *q = sc->device->request_queue;
1001 		unsigned long flags;
1002 
1003 		spin_lock_irqsave(q->queue_lock, flags);
1004 		blk_abort_request(sc->request);
1005 		spin_unlock_irqrestore(q->queue_lock, flags);
1006 		scsi_schedule_eh(sc->device->host);
1007 	}
1008 }
1009 
sas_target_destroy(struct scsi_target * starget)1010 void sas_target_destroy(struct scsi_target *starget)
1011 {
1012 	struct domain_device *found_dev = starget->hostdata;
1013 
1014 	if (!found_dev)
1015 		return;
1016 
1017 	starget->hostdata = NULL;
1018 	sas_put_device(found_dev);
1019 }
1020 
sas_parse_addr(u8 * sas_addr,const char * p)1021 static void sas_parse_addr(u8 *sas_addr, const char *p)
1022 {
1023 	int i;
1024 	for (i = 0; i < SAS_ADDR_SIZE; i++) {
1025 		u8 h, l;
1026 		if (!*p)
1027 			break;
1028 		h = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1029 		p++;
1030 		l = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1031 		p++;
1032 		sas_addr[i] = (h<<4) | l;
1033 	}
1034 }
1035 
1036 #define SAS_STRING_ADDR_SIZE	16
1037 
sas_request_addr(struct Scsi_Host * shost,u8 * addr)1038 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
1039 {
1040 	int res;
1041 	const struct firmware *fw;
1042 
1043 	res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
1044 	if (res)
1045 		return res;
1046 
1047 	if (fw->size < SAS_STRING_ADDR_SIZE) {
1048 		res = -ENODEV;
1049 		goto out;
1050 	}
1051 
1052 	sas_parse_addr(addr, fw->data);
1053 
1054 out:
1055 	release_firmware(fw);
1056 	return res;
1057 }
1058 EXPORT_SYMBOL_GPL(sas_request_addr);
1059 
1060 EXPORT_SYMBOL_GPL(sas_queuecommand);
1061 EXPORT_SYMBOL_GPL(sas_target_alloc);
1062 EXPORT_SYMBOL_GPL(sas_slave_configure);
1063 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
1064 EXPORT_SYMBOL_GPL(sas_change_queue_type);
1065 EXPORT_SYMBOL_GPL(sas_bios_param);
1066 EXPORT_SYMBOL_GPL(sas_task_abort);
1067 EXPORT_SYMBOL_GPL(sas_phy_reset);
1068 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1069 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);
1070 EXPORT_SYMBOL_GPL(sas_target_destroy);
1071 EXPORT_SYMBOL_GPL(sas_ioctl);
1072