xref: /openbmc/linux/drivers/scsi/libsas/sas_init.c (revision 12eb4683)
1 /*
2  * Serial Attached SCSI (SAS) Transport Layer initialization
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/module.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/device.h>
30 #include <linux/spinlock.h>
31 #include <scsi/sas_ata.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_device.h>
34 #include <scsi/scsi_transport.h>
35 #include <scsi/scsi_transport_sas.h>
36 
37 #include "sas_internal.h"
38 
39 #include "../scsi_sas_internal.h"
40 
41 static struct kmem_cache *sas_task_cache;
42 
43 struct sas_task *sas_alloc_task(gfp_t flags)
44 {
45 	struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
46 
47 	if (task) {
48 		INIT_LIST_HEAD(&task->list);
49 		spin_lock_init(&task->task_state_lock);
50 		task->task_state_flags = SAS_TASK_STATE_PENDING;
51 	}
52 
53 	return task;
54 }
55 EXPORT_SYMBOL_GPL(sas_alloc_task);
56 
57 struct sas_task *sas_alloc_slow_task(gfp_t flags)
58 {
59 	struct sas_task *task = sas_alloc_task(flags);
60 	struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
61 
62 	if (!task || !slow) {
63 		if (task)
64 			kmem_cache_free(sas_task_cache, task);
65 		kfree(slow);
66 		return NULL;
67 	}
68 
69 	task->slow_task = slow;
70 	init_timer(&slow->timer);
71 	init_completion(&slow->completion);
72 
73 	return task;
74 }
75 EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
76 
77 void sas_free_task(struct sas_task *task)
78 {
79 	if (task) {
80 		BUG_ON(!list_empty(&task->list));
81 		kfree(task->slow_task);
82 		kmem_cache_free(sas_task_cache, task);
83 	}
84 }
85 EXPORT_SYMBOL_GPL(sas_free_task);
86 
87 /*------------ SAS addr hash -----------*/
88 void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
89 {
90         const u32 poly = 0x00DB2777;
91         u32     r = 0;
92         int     i;
93 
94         for (i = 0; i < 8; i++) {
95                 int b;
96                 for (b = 7; b >= 0; b--) {
97                         r <<= 1;
98                         if ((1 << b) & sas_addr[i]) {
99                                 if (!(r & 0x01000000))
100                                         r ^= poly;
101                         } else if (r & 0x01000000)
102                                 r ^= poly;
103                 }
104         }
105 
106         hashed[0] = (r >> 16) & 0xFF;
107         hashed[1] = (r >> 8) & 0xFF ;
108         hashed[2] = r & 0xFF;
109 }
110 
111 
112 /* ---------- HA events ---------- */
113 
114 void sas_hae_reset(struct work_struct *work)
115 {
116 	struct sas_ha_event *ev = to_sas_ha_event(work);
117 	struct sas_ha_struct *ha = ev->ha;
118 
119 	clear_bit(HAE_RESET, &ha->pending);
120 }
121 
122 int sas_register_ha(struct sas_ha_struct *sas_ha)
123 {
124 	int error = 0;
125 
126 	mutex_init(&sas_ha->disco_mutex);
127 	spin_lock_init(&sas_ha->phy_port_lock);
128 	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
129 
130 	if (sas_ha->lldd_queue_size == 0)
131 		sas_ha->lldd_queue_size = 1;
132 	else if (sas_ha->lldd_queue_size == -1)
133 		sas_ha->lldd_queue_size = 128; /* Sanity */
134 
135 	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
136 	spin_lock_init(&sas_ha->lock);
137 	mutex_init(&sas_ha->drain_mutex);
138 	init_waitqueue_head(&sas_ha->eh_wait_q);
139 	INIT_LIST_HEAD(&sas_ha->defer_q);
140 	INIT_LIST_HEAD(&sas_ha->eh_dev_q);
141 
142 	error = sas_register_phys(sas_ha);
143 	if (error) {
144 		printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
145 		return error;
146 	}
147 
148 	error = sas_register_ports(sas_ha);
149 	if (error) {
150 		printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
151 		goto Undo_phys;
152 	}
153 
154 	error = sas_init_events(sas_ha);
155 	if (error) {
156 		printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
157 		goto Undo_ports;
158 	}
159 
160 	if (sas_ha->lldd_max_execute_num > 1) {
161 		error = sas_init_queue(sas_ha);
162 		if (error) {
163 			printk(KERN_NOTICE "couldn't start queue thread:%d, "
164 			       "running in direct mode\n", error);
165 			sas_ha->lldd_max_execute_num = 1;
166 		}
167 	}
168 
169 	INIT_LIST_HEAD(&sas_ha->eh_done_q);
170 	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
171 
172 	return 0;
173 
174 Undo_ports:
175 	sas_unregister_ports(sas_ha);
176 Undo_phys:
177 
178 	return error;
179 }
180 
181 static void sas_disable_events(struct sas_ha_struct *sas_ha)
182 {
183 	/* Set the state to unregistered to avoid further unchained
184 	 * events to be queued, and flush any in-progress drainers
185 	 */
186 	mutex_lock(&sas_ha->drain_mutex);
187 	spin_lock_irq(&sas_ha->lock);
188 	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
189 	spin_unlock_irq(&sas_ha->lock);
190 	__sas_drain_work(sas_ha);
191 	mutex_unlock(&sas_ha->drain_mutex);
192 }
193 
194 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
195 {
196 	sas_disable_events(sas_ha);
197 	sas_unregister_ports(sas_ha);
198 
199 	/* flush unregistration work */
200 	mutex_lock(&sas_ha->drain_mutex);
201 	__sas_drain_work(sas_ha);
202 	mutex_unlock(&sas_ha->drain_mutex);
203 
204 	if (sas_ha->lldd_max_execute_num > 1) {
205 		sas_shutdown_queue(sas_ha);
206 		sas_ha->lldd_max_execute_num = 1;
207 	}
208 
209 	return 0;
210 }
211 
212 static int sas_get_linkerrors(struct sas_phy *phy)
213 {
214 	if (scsi_is_sas_phy_local(phy)) {
215 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
216 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
217 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
218 		struct sas_internal *i =
219 			to_sas_internal(sas_ha->core.shost->transportt);
220 
221 		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
222 	}
223 
224 	return sas_smp_get_phy_events(phy);
225 }
226 
227 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
228 {
229 	struct domain_device *dev = NULL;
230 
231 	/* try to route user requested link resets through libata */
232 	if (asd_phy->port)
233 		dev = asd_phy->port->port_dev;
234 
235 	/* validate that dev has been probed */
236 	if (dev)
237 		dev = sas_find_dev_by_rphy(dev->rphy);
238 
239 	if (dev && dev_is_sata(dev)) {
240 		sas_ata_schedule_reset(dev);
241 		sas_ata_wait_eh(dev);
242 		return 0;
243 	}
244 
245 	return -ENODEV;
246 }
247 
248 /**
249  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
250  *
251  * phy reset request via sysfs in host workqueue context so we know we
252  * can block on eh and safely traverse the domain_device topology
253  */
254 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
255 {
256 	enum phy_func reset_type;
257 
258 	if (hard_reset)
259 		reset_type = PHY_FUNC_HARD_RESET;
260 	else
261 		reset_type = PHY_FUNC_LINK_RESET;
262 
263 	if (scsi_is_sas_phy_local(phy)) {
264 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
265 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
266 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
267 		struct sas_internal *i =
268 			to_sas_internal(sas_ha->core.shost->transportt);
269 
270 		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
271 			return 0;
272 		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
273 	} else {
274 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
275 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
276 		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
277 
278 		if (ata_dev && !hard_reset) {
279 			sas_ata_schedule_reset(ata_dev);
280 			sas_ata_wait_eh(ata_dev);
281 			return 0;
282 		} else
283 			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
284 	}
285 }
286 
287 static int sas_phy_enable(struct sas_phy *phy, int enable)
288 {
289 	int ret;
290 	enum phy_func cmd;
291 
292 	if (enable)
293 		cmd = PHY_FUNC_LINK_RESET;
294 	else
295 		cmd = PHY_FUNC_DISABLE;
296 
297 	if (scsi_is_sas_phy_local(phy)) {
298 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
299 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
300 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
301 		struct sas_internal *i =
302 			to_sas_internal(sas_ha->core.shost->transportt);
303 
304 		if (enable)
305 			ret = transport_sas_phy_reset(phy, 0);
306 		else
307 			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
308 	} else {
309 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
310 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
311 
312 		if (enable)
313 			ret = transport_sas_phy_reset(phy, 0);
314 		else
315 			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
316 	}
317 	return ret;
318 }
319 
320 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
321 {
322 	int ret;
323 	enum phy_func reset_type;
324 
325 	if (!phy->enabled)
326 		return -ENODEV;
327 
328 	if (hard_reset)
329 		reset_type = PHY_FUNC_HARD_RESET;
330 	else
331 		reset_type = PHY_FUNC_LINK_RESET;
332 
333 	if (scsi_is_sas_phy_local(phy)) {
334 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
335 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
336 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
337 		struct sas_internal *i =
338 			to_sas_internal(sas_ha->core.shost->transportt);
339 
340 		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
341 	} else {
342 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
343 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
344 		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
345 	}
346 	return ret;
347 }
348 
349 int sas_set_phy_speed(struct sas_phy *phy,
350 		      struct sas_phy_linkrates *rates)
351 {
352 	int ret;
353 
354 	if ((rates->minimum_linkrate &&
355 	     rates->minimum_linkrate > phy->maximum_linkrate) ||
356 	    (rates->maximum_linkrate &&
357 	     rates->maximum_linkrate < phy->minimum_linkrate))
358 		return -EINVAL;
359 
360 	if (rates->minimum_linkrate &&
361 	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
362 		rates->minimum_linkrate = phy->minimum_linkrate_hw;
363 
364 	if (rates->maximum_linkrate &&
365 	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
366 		rates->maximum_linkrate = phy->maximum_linkrate_hw;
367 
368 	if (scsi_is_sas_phy_local(phy)) {
369 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
370 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
371 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
372 		struct sas_internal *i =
373 			to_sas_internal(sas_ha->core.shost->transportt);
374 
375 		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
376 					       rates);
377 	} else {
378 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
379 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
380 		ret = sas_smp_phy_control(ddev, phy->number,
381 					  PHY_FUNC_LINK_RESET, rates);
382 
383 	}
384 
385 	return ret;
386 }
387 
388 void sas_prep_resume_ha(struct sas_ha_struct *ha)
389 {
390 	int i;
391 
392 	set_bit(SAS_HA_REGISTERED, &ha->state);
393 
394 	/* clear out any stale link events/data from the suspension path */
395 	for (i = 0; i < ha->num_phys; i++) {
396 		struct asd_sas_phy *phy = ha->sas_phy[i];
397 
398 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
399 		phy->port_events_pending = 0;
400 		phy->phy_events_pending = 0;
401 		phy->frame_rcvd_size = 0;
402 	}
403 }
404 EXPORT_SYMBOL(sas_prep_resume_ha);
405 
406 static int phys_suspended(struct sas_ha_struct *ha)
407 {
408 	int i, rc = 0;
409 
410 	for (i = 0; i < ha->num_phys; i++) {
411 		struct asd_sas_phy *phy = ha->sas_phy[i];
412 
413 		if (phy->suspended)
414 			rc++;
415 	}
416 
417 	return rc;
418 }
419 
420 void sas_resume_ha(struct sas_ha_struct *ha)
421 {
422 	const unsigned long tmo = msecs_to_jiffies(25000);
423 	int i;
424 
425 	/* deform ports on phys that did not resume
426 	 * at this point we may be racing the phy coming back (as posted
427 	 * by the lldd).  So we post the event and once we are in the
428 	 * libsas context check that the phy remains suspended before
429 	 * tearing it down.
430 	 */
431 	i = phys_suspended(ha);
432 	if (i)
433 		dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
434 			 i, i > 1 ? "s" : "");
435 	wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
436 	for (i = 0; i < ha->num_phys; i++) {
437 		struct asd_sas_phy *phy = ha->sas_phy[i];
438 
439 		if (phy->suspended) {
440 			dev_warn(&phy->phy->dev, "resume timeout\n");
441 			sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT);
442 		}
443 	}
444 
445 	/* all phys are back up or timed out, turn on i/o so we can
446 	 * flush out disks that did not return
447 	 */
448 	scsi_unblock_requests(ha->core.shost);
449 	sas_drain_work(ha);
450 }
451 EXPORT_SYMBOL(sas_resume_ha);
452 
453 void sas_suspend_ha(struct sas_ha_struct *ha)
454 {
455 	int i;
456 
457 	sas_disable_events(ha);
458 	scsi_block_requests(ha->core.shost);
459 	for (i = 0; i < ha->num_phys; i++) {
460 		struct asd_sas_port *port = ha->sas_port[i];
461 
462 		sas_discover_event(port, DISCE_SUSPEND);
463 	}
464 
465 	/* flush suspend events while unregistered */
466 	mutex_lock(&ha->drain_mutex);
467 	__sas_drain_work(ha);
468 	mutex_unlock(&ha->drain_mutex);
469 }
470 EXPORT_SYMBOL(sas_suspend_ha);
471 
472 static void sas_phy_release(struct sas_phy *phy)
473 {
474 	kfree(phy->hostdata);
475 	phy->hostdata = NULL;
476 }
477 
478 static void phy_reset_work(struct work_struct *work)
479 {
480 	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
481 
482 	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
483 }
484 
485 static void phy_enable_work(struct work_struct *work)
486 {
487 	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
488 
489 	d->enable_result = sas_phy_enable(d->phy, d->enable);
490 }
491 
492 static int sas_phy_setup(struct sas_phy *phy)
493 {
494 	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
495 
496 	if (!d)
497 		return -ENOMEM;
498 
499 	mutex_init(&d->event_lock);
500 	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
501 	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
502 	d->phy = phy;
503 	phy->hostdata = d;
504 
505 	return 0;
506 }
507 
508 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
509 {
510 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
511 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
512 	struct sas_phy_data *d = phy->hostdata;
513 	int rc;
514 
515 	if (!d)
516 		return -ENOMEM;
517 
518 	/* libsas workqueue coordinates ata-eh reset with discovery */
519 	mutex_lock(&d->event_lock);
520 	d->reset_result = 0;
521 	d->hard_reset = hard_reset;
522 
523 	spin_lock_irq(&ha->lock);
524 	sas_queue_work(ha, &d->reset_work);
525 	spin_unlock_irq(&ha->lock);
526 
527 	rc = sas_drain_work(ha);
528 	if (rc == 0)
529 		rc = d->reset_result;
530 	mutex_unlock(&d->event_lock);
531 
532 	return rc;
533 }
534 
535 static int queue_phy_enable(struct sas_phy *phy, int enable)
536 {
537 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
538 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
539 	struct sas_phy_data *d = phy->hostdata;
540 	int rc;
541 
542 	if (!d)
543 		return -ENOMEM;
544 
545 	/* libsas workqueue coordinates ata-eh reset with discovery */
546 	mutex_lock(&d->event_lock);
547 	d->enable_result = 0;
548 	d->enable = enable;
549 
550 	spin_lock_irq(&ha->lock);
551 	sas_queue_work(ha, &d->enable_work);
552 	spin_unlock_irq(&ha->lock);
553 
554 	rc = sas_drain_work(ha);
555 	if (rc == 0)
556 		rc = d->enable_result;
557 	mutex_unlock(&d->event_lock);
558 
559 	return rc;
560 }
561 
562 static struct sas_function_template sft = {
563 	.phy_enable = queue_phy_enable,
564 	.phy_reset = queue_phy_reset,
565 	.phy_setup = sas_phy_setup,
566 	.phy_release = sas_phy_release,
567 	.set_phy_speed = sas_set_phy_speed,
568 	.get_linkerrors = sas_get_linkerrors,
569 	.smp_handler = sas_smp_handler,
570 };
571 
572 struct scsi_transport_template *
573 sas_domain_attach_transport(struct sas_domain_function_template *dft)
574 {
575 	struct scsi_transport_template *stt = sas_attach_transport(&sft);
576 	struct sas_internal *i;
577 
578 	if (!stt)
579 		return stt;
580 
581 	i = to_sas_internal(stt);
582 	i->dft = dft;
583 	stt->create_work_queue = 1;
584 	stt->eh_timed_out = sas_scsi_timed_out;
585 	stt->eh_strategy_handler = sas_scsi_recover_host;
586 
587 	return stt;
588 }
589 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
590 
591 
592 void sas_domain_release_transport(struct scsi_transport_template *stt)
593 {
594 	sas_release_transport(stt);
595 }
596 EXPORT_SYMBOL_GPL(sas_domain_release_transport);
597 
598 /* ---------- SAS Class register/unregister ---------- */
599 
600 static int __init sas_class_init(void)
601 {
602 	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
603 	if (!sas_task_cache)
604 		return -ENOMEM;
605 
606 	return 0;
607 }
608 
609 static void __exit sas_class_exit(void)
610 {
611 	kmem_cache_destroy(sas_task_cache);
612 }
613 
614 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
615 MODULE_DESCRIPTION("SAS Transport Layer");
616 MODULE_LICENSE("GPL v2");
617 
618 module_init(sas_class_init);
619 module_exit(sas_class_exit);
620 
621 EXPORT_SYMBOL_GPL(sas_register_ha);
622 EXPORT_SYMBOL_GPL(sas_unregister_ha);
623