xref: /openbmc/linux/drivers/scsi/libsas/sas_init.c (revision 4a3fad70)
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 		spin_lock_init(&task->task_state_lock);
49 		task->task_state_flags = SAS_TASK_STATE_PENDING;
50 	}
51 
52 	return task;
53 }
54 EXPORT_SYMBOL_GPL(sas_alloc_task);
55 
56 struct sas_task *sas_alloc_slow_task(gfp_t flags)
57 {
58 	struct sas_task *task = sas_alloc_task(flags);
59 	struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
60 
61 	if (!task || !slow) {
62 		if (task)
63 			kmem_cache_free(sas_task_cache, task);
64 		kfree(slow);
65 		return NULL;
66 	}
67 
68 	task->slow_task = slow;
69 	slow->task = task;
70 	timer_setup(&slow->timer, NULL, 0);
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 		kfree(task->slow_task);
81 		kmem_cache_free(sas_task_cache, task);
82 	}
83 }
84 EXPORT_SYMBOL_GPL(sas_free_task);
85 
86 /*------------ SAS addr hash -----------*/
87 void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
88 {
89         const u32 poly = 0x00DB2777;
90         u32     r = 0;
91         int     i;
92 
93         for (i = 0; i < 8; i++) {
94                 int b;
95                 for (b = 7; b >= 0; b--) {
96                         r <<= 1;
97                         if ((1 << b) & sas_addr[i]) {
98                                 if (!(r & 0x01000000))
99                                         r ^= poly;
100                         } else if (r & 0x01000000)
101                                 r ^= poly;
102                 }
103         }
104 
105         hashed[0] = (r >> 16) & 0xFF;
106         hashed[1] = (r >> 8) & 0xFF ;
107         hashed[2] = r & 0xFF;
108 }
109 
110 int sas_register_ha(struct sas_ha_struct *sas_ha)
111 {
112 	int error = 0;
113 
114 	mutex_init(&sas_ha->disco_mutex);
115 	spin_lock_init(&sas_ha->phy_port_lock);
116 	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
117 
118 	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
119 	spin_lock_init(&sas_ha->lock);
120 	mutex_init(&sas_ha->drain_mutex);
121 	init_waitqueue_head(&sas_ha->eh_wait_q);
122 	INIT_LIST_HEAD(&sas_ha->defer_q);
123 	INIT_LIST_HEAD(&sas_ha->eh_dev_q);
124 
125 	error = sas_register_phys(sas_ha);
126 	if (error) {
127 		printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
128 		return error;
129 	}
130 
131 	error = sas_register_ports(sas_ha);
132 	if (error) {
133 		printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
134 		goto Undo_phys;
135 	}
136 
137 	error = sas_init_events(sas_ha);
138 	if (error) {
139 		printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
140 		goto Undo_ports;
141 	}
142 
143 	INIT_LIST_HEAD(&sas_ha->eh_done_q);
144 	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
145 
146 	return 0;
147 Undo_ports:
148 	sas_unregister_ports(sas_ha);
149 Undo_phys:
150 
151 	return error;
152 }
153 
154 static void sas_disable_events(struct sas_ha_struct *sas_ha)
155 {
156 	/* Set the state to unregistered to avoid further unchained
157 	 * events to be queued, and flush any in-progress drainers
158 	 */
159 	mutex_lock(&sas_ha->drain_mutex);
160 	spin_lock_irq(&sas_ha->lock);
161 	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
162 	spin_unlock_irq(&sas_ha->lock);
163 	__sas_drain_work(sas_ha);
164 	mutex_unlock(&sas_ha->drain_mutex);
165 }
166 
167 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
168 {
169 	sas_disable_events(sas_ha);
170 	sas_unregister_ports(sas_ha);
171 
172 	/* flush unregistration work */
173 	mutex_lock(&sas_ha->drain_mutex);
174 	__sas_drain_work(sas_ha);
175 	mutex_unlock(&sas_ha->drain_mutex);
176 
177 	return 0;
178 }
179 
180 static int sas_get_linkerrors(struct sas_phy *phy)
181 {
182 	if (scsi_is_sas_phy_local(phy)) {
183 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
184 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
185 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
186 		struct sas_internal *i =
187 			to_sas_internal(sas_ha->core.shost->transportt);
188 
189 		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
190 	}
191 
192 	return sas_smp_get_phy_events(phy);
193 }
194 
195 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
196 {
197 	struct domain_device *dev = NULL;
198 
199 	/* try to route user requested link resets through libata */
200 	if (asd_phy->port)
201 		dev = asd_phy->port->port_dev;
202 
203 	/* validate that dev has been probed */
204 	if (dev)
205 		dev = sas_find_dev_by_rphy(dev->rphy);
206 
207 	if (dev && dev_is_sata(dev)) {
208 		sas_ata_schedule_reset(dev);
209 		sas_ata_wait_eh(dev);
210 		return 0;
211 	}
212 
213 	return -ENODEV;
214 }
215 
216 /**
217  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
218  *
219  * phy reset request via sysfs in host workqueue context so we know we
220  * can block on eh and safely traverse the domain_device topology
221  */
222 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
223 {
224 	enum phy_func reset_type;
225 
226 	if (hard_reset)
227 		reset_type = PHY_FUNC_HARD_RESET;
228 	else
229 		reset_type = PHY_FUNC_LINK_RESET;
230 
231 	if (scsi_is_sas_phy_local(phy)) {
232 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
233 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
234 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
235 		struct sas_internal *i =
236 			to_sas_internal(sas_ha->core.shost->transportt);
237 
238 		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
239 			return 0;
240 		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
241 	} else {
242 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
243 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
244 		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
245 
246 		if (ata_dev && !hard_reset) {
247 			sas_ata_schedule_reset(ata_dev);
248 			sas_ata_wait_eh(ata_dev);
249 			return 0;
250 		} else
251 			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
252 	}
253 }
254 
255 static int sas_phy_enable(struct sas_phy *phy, int enable)
256 {
257 	int ret;
258 	enum phy_func cmd;
259 
260 	if (enable)
261 		cmd = PHY_FUNC_LINK_RESET;
262 	else
263 		cmd = PHY_FUNC_DISABLE;
264 
265 	if (scsi_is_sas_phy_local(phy)) {
266 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
267 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
268 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
269 		struct sas_internal *i =
270 			to_sas_internal(sas_ha->core.shost->transportt);
271 
272 		if (enable)
273 			ret = transport_sas_phy_reset(phy, 0);
274 		else
275 			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
276 	} else {
277 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
278 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
279 
280 		if (enable)
281 			ret = transport_sas_phy_reset(phy, 0);
282 		else
283 			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
284 	}
285 	return ret;
286 }
287 
288 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
289 {
290 	int ret;
291 	enum phy_func reset_type;
292 
293 	if (!phy->enabled)
294 		return -ENODEV;
295 
296 	if (hard_reset)
297 		reset_type = PHY_FUNC_HARD_RESET;
298 	else
299 		reset_type = PHY_FUNC_LINK_RESET;
300 
301 	if (scsi_is_sas_phy_local(phy)) {
302 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
303 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
304 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
305 		struct sas_internal *i =
306 			to_sas_internal(sas_ha->core.shost->transportt);
307 
308 		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
309 	} else {
310 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
311 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
312 		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
313 	}
314 	return ret;
315 }
316 
317 int sas_set_phy_speed(struct sas_phy *phy,
318 		      struct sas_phy_linkrates *rates)
319 {
320 	int ret;
321 
322 	if ((rates->minimum_linkrate &&
323 	     rates->minimum_linkrate > phy->maximum_linkrate) ||
324 	    (rates->maximum_linkrate &&
325 	     rates->maximum_linkrate < phy->minimum_linkrate))
326 		return -EINVAL;
327 
328 	if (rates->minimum_linkrate &&
329 	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
330 		rates->minimum_linkrate = phy->minimum_linkrate_hw;
331 
332 	if (rates->maximum_linkrate &&
333 	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
334 		rates->maximum_linkrate = phy->maximum_linkrate_hw;
335 
336 	if (scsi_is_sas_phy_local(phy)) {
337 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
338 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
339 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
340 		struct sas_internal *i =
341 			to_sas_internal(sas_ha->core.shost->transportt);
342 
343 		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
344 					       rates);
345 	} else {
346 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
347 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
348 		ret = sas_smp_phy_control(ddev, phy->number,
349 					  PHY_FUNC_LINK_RESET, rates);
350 
351 	}
352 
353 	return ret;
354 }
355 
356 void sas_prep_resume_ha(struct sas_ha_struct *ha)
357 {
358 	int i;
359 
360 	set_bit(SAS_HA_REGISTERED, &ha->state);
361 
362 	/* clear out any stale link events/data from the suspension path */
363 	for (i = 0; i < ha->num_phys; i++) {
364 		struct asd_sas_phy *phy = ha->sas_phy[i];
365 
366 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
367 		phy->port_events_pending = 0;
368 		phy->phy_events_pending = 0;
369 		phy->frame_rcvd_size = 0;
370 	}
371 }
372 EXPORT_SYMBOL(sas_prep_resume_ha);
373 
374 static int phys_suspended(struct sas_ha_struct *ha)
375 {
376 	int i, rc = 0;
377 
378 	for (i = 0; i < ha->num_phys; i++) {
379 		struct asd_sas_phy *phy = ha->sas_phy[i];
380 
381 		if (phy->suspended)
382 			rc++;
383 	}
384 
385 	return rc;
386 }
387 
388 void sas_resume_ha(struct sas_ha_struct *ha)
389 {
390 	const unsigned long tmo = msecs_to_jiffies(25000);
391 	int i;
392 
393 	/* deform ports on phys that did not resume
394 	 * at this point we may be racing the phy coming back (as posted
395 	 * by the lldd).  So we post the event and once we are in the
396 	 * libsas context check that the phy remains suspended before
397 	 * tearing it down.
398 	 */
399 	i = phys_suspended(ha);
400 	if (i)
401 		dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
402 			 i, i > 1 ? "s" : "");
403 	wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
404 	for (i = 0; i < ha->num_phys; i++) {
405 		struct asd_sas_phy *phy = ha->sas_phy[i];
406 
407 		if (phy->suspended) {
408 			dev_warn(&phy->phy->dev, "resume timeout\n");
409 			sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT);
410 		}
411 	}
412 
413 	/* all phys are back up or timed out, turn on i/o so we can
414 	 * flush out disks that did not return
415 	 */
416 	scsi_unblock_requests(ha->core.shost);
417 	sas_drain_work(ha);
418 }
419 EXPORT_SYMBOL(sas_resume_ha);
420 
421 void sas_suspend_ha(struct sas_ha_struct *ha)
422 {
423 	int i;
424 
425 	sas_disable_events(ha);
426 	scsi_block_requests(ha->core.shost);
427 	for (i = 0; i < ha->num_phys; i++) {
428 		struct asd_sas_port *port = ha->sas_port[i];
429 
430 		sas_discover_event(port, DISCE_SUSPEND);
431 	}
432 
433 	/* flush suspend events while unregistered */
434 	mutex_lock(&ha->drain_mutex);
435 	__sas_drain_work(ha);
436 	mutex_unlock(&ha->drain_mutex);
437 }
438 EXPORT_SYMBOL(sas_suspend_ha);
439 
440 static void sas_phy_release(struct sas_phy *phy)
441 {
442 	kfree(phy->hostdata);
443 	phy->hostdata = NULL;
444 }
445 
446 static void phy_reset_work(struct work_struct *work)
447 {
448 	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
449 
450 	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
451 }
452 
453 static void phy_enable_work(struct work_struct *work)
454 {
455 	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
456 
457 	d->enable_result = sas_phy_enable(d->phy, d->enable);
458 }
459 
460 static int sas_phy_setup(struct sas_phy *phy)
461 {
462 	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
463 
464 	if (!d)
465 		return -ENOMEM;
466 
467 	mutex_init(&d->event_lock);
468 	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
469 	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
470 	d->phy = phy;
471 	phy->hostdata = d;
472 
473 	return 0;
474 }
475 
476 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
477 {
478 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
479 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
480 	struct sas_phy_data *d = phy->hostdata;
481 	int rc;
482 
483 	if (!d)
484 		return -ENOMEM;
485 
486 	/* libsas workqueue coordinates ata-eh reset with discovery */
487 	mutex_lock(&d->event_lock);
488 	d->reset_result = 0;
489 	d->hard_reset = hard_reset;
490 
491 	spin_lock_irq(&ha->lock);
492 	sas_queue_work(ha, &d->reset_work);
493 	spin_unlock_irq(&ha->lock);
494 
495 	rc = sas_drain_work(ha);
496 	if (rc == 0)
497 		rc = d->reset_result;
498 	mutex_unlock(&d->event_lock);
499 
500 	return rc;
501 }
502 
503 static int queue_phy_enable(struct sas_phy *phy, int enable)
504 {
505 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
506 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
507 	struct sas_phy_data *d = phy->hostdata;
508 	int rc;
509 
510 	if (!d)
511 		return -ENOMEM;
512 
513 	/* libsas workqueue coordinates ata-eh reset with discovery */
514 	mutex_lock(&d->event_lock);
515 	d->enable_result = 0;
516 	d->enable = enable;
517 
518 	spin_lock_irq(&ha->lock);
519 	sas_queue_work(ha, &d->enable_work);
520 	spin_unlock_irq(&ha->lock);
521 
522 	rc = sas_drain_work(ha);
523 	if (rc == 0)
524 		rc = d->enable_result;
525 	mutex_unlock(&d->event_lock);
526 
527 	return rc;
528 }
529 
530 static struct sas_function_template sft = {
531 	.phy_enable = queue_phy_enable,
532 	.phy_reset = queue_phy_reset,
533 	.phy_setup = sas_phy_setup,
534 	.phy_release = sas_phy_release,
535 	.set_phy_speed = sas_set_phy_speed,
536 	.get_linkerrors = sas_get_linkerrors,
537 	.smp_handler = sas_smp_handler,
538 };
539 
540 struct scsi_transport_template *
541 sas_domain_attach_transport(struct sas_domain_function_template *dft)
542 {
543 	struct scsi_transport_template *stt = sas_attach_transport(&sft);
544 	struct sas_internal *i;
545 
546 	if (!stt)
547 		return stt;
548 
549 	i = to_sas_internal(stt);
550 	i->dft = dft;
551 	stt->create_work_queue = 1;
552 	stt->eh_strategy_handler = sas_scsi_recover_host;
553 
554 	return stt;
555 }
556 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
557 
558 /* ---------- SAS Class register/unregister ---------- */
559 
560 static int __init sas_class_init(void)
561 {
562 	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
563 	if (!sas_task_cache)
564 		return -ENOMEM;
565 
566 	return 0;
567 }
568 
569 static void __exit sas_class_exit(void)
570 {
571 	kmem_cache_destroy(sas_task_cache);
572 }
573 
574 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
575 MODULE_DESCRIPTION("SAS Transport Layer");
576 MODULE_LICENSE("GPL v2");
577 
578 module_init(sas_class_init);
579 module_exit(sas_class_exit);
580 
581 EXPORT_SYMBOL_GPL(sas_register_ha);
582 EXPORT_SYMBOL_GPL(sas_unregister_ha);
583