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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Serial Attached SCSI (SAS) Transport Layer initialization
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/module.h>
10#include <linux/slab.h>
11#include <linux/init.h>
12#include <linux/device.h>
13#include <linux/spinlock.h>
14#include <scsi/sas_ata.h>
15#include <scsi/scsi_host.h>
16#include <scsi/scsi_device.h>
17#include <scsi/scsi_transport.h>
18#include <scsi/scsi_transport_sas.h>
19
20#include "sas_internal.h"
21
22#include "scsi_sas_internal.h"
23
24static struct kmem_cache *sas_task_cache;
25static struct kmem_cache *sas_event_cache;
26
27struct sas_task *sas_alloc_task(gfp_t flags)
28{
29 struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
30
31 if (task) {
32 spin_lock_init(&task->task_state_lock);
33 task->task_state_flags = SAS_TASK_STATE_PENDING;
34 }
35
36 return task;
37}
38
39struct sas_task *sas_alloc_slow_task(gfp_t flags)
40{
41 struct sas_task *task = sas_alloc_task(flags);
42 struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
43
44 if (!task || !slow) {
45 if (task)
46 kmem_cache_free(sas_task_cache, task);
47 kfree(slow);
48 return NULL;
49 }
50
51 task->slow_task = slow;
52 slow->task = task;
53 timer_setup(&slow->timer, NULL, 0);
54 init_completion(&slow->completion);
55
56 return task;
57}
58
59void sas_free_task(struct sas_task *task)
60{
61 if (task) {
62 kfree(task->slow_task);
63 kmem_cache_free(sas_task_cache, task);
64 }
65}
66
67/*------------ SAS addr hash -----------*/
68void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
69{
70 const u32 poly = 0x00DB2777;
71 u32 r = 0;
72 int i;
73
74 for (i = 0; i < SAS_ADDR_SIZE; i++) {
75 int b;
76
77 for (b = (SAS_ADDR_SIZE - 1); b >= 0; b--) {
78 r <<= 1;
79 if ((1 << b) & sas_addr[i]) {
80 if (!(r & 0x01000000))
81 r ^= poly;
82 } else if (r & 0x01000000) {
83 r ^= poly;
84 }
85 }
86 }
87
88 hashed[0] = (r >> 16) & 0xFF;
89 hashed[1] = (r >> 8) & 0xFF;
90 hashed[2] = r & 0xFF;
91}
92
93int sas_register_ha(struct sas_ha_struct *sas_ha)
94{
95 char name[64];
96 int error = 0;
97
98 mutex_init(&sas_ha->disco_mutex);
99 spin_lock_init(&sas_ha->phy_port_lock);
100 sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
101
102 set_bit(SAS_HA_REGISTERED, &sas_ha->state);
103 spin_lock_init(&sas_ha->lock);
104 mutex_init(&sas_ha->drain_mutex);
105 init_waitqueue_head(&sas_ha->eh_wait_q);
106 INIT_LIST_HEAD(&sas_ha->defer_q);
107 INIT_LIST_HEAD(&sas_ha->eh_dev_q);
108
109 sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
110
111 error = sas_register_phys(sas_ha);
112 if (error) {
113 pr_notice("couldn't register sas phys:%d\n", error);
114 return error;
115 }
116
117 error = sas_register_ports(sas_ha);
118 if (error) {
119 pr_notice("couldn't register sas ports:%d\n", error);
120 goto Undo_phys;
121 }
122
123 error = -ENOMEM;
124 snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev));
125 sas_ha->event_q = create_singlethread_workqueue(name);
126 if (!sas_ha->event_q)
127 goto Undo_ports;
128
129 snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev));
130 sas_ha->disco_q = create_singlethread_workqueue(name);
131 if (!sas_ha->disco_q)
132 goto Undo_event_q;
133
134 INIT_LIST_HEAD(&sas_ha->eh_done_q);
135 INIT_LIST_HEAD(&sas_ha->eh_ata_q);
136
137 return 0;
138
139Undo_event_q:
140 destroy_workqueue(sas_ha->event_q);
141Undo_ports:
142 sas_unregister_ports(sas_ha);
143Undo_phys:
144
145 return error;
146}
147EXPORT_SYMBOL_GPL(sas_register_ha);
148
149static void sas_disable_events(struct sas_ha_struct *sas_ha)
150{
151 /* Set the state to unregistered to avoid further unchained
152 * events to be queued, and flush any in-progress drainers
153 */
154 mutex_lock(&sas_ha->drain_mutex);
155 spin_lock_irq(&sas_ha->lock);
156 clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
157 spin_unlock_irq(&sas_ha->lock);
158 __sas_drain_work(sas_ha);
159 mutex_unlock(&sas_ha->drain_mutex);
160}
161
162int sas_unregister_ha(struct sas_ha_struct *sas_ha)
163{
164 sas_disable_events(sas_ha);
165 sas_unregister_ports(sas_ha);
166
167 /* flush unregistration work */
168 mutex_lock(&sas_ha->drain_mutex);
169 __sas_drain_work(sas_ha);
170 mutex_unlock(&sas_ha->drain_mutex);
171
172 destroy_workqueue(sas_ha->disco_q);
173 destroy_workqueue(sas_ha->event_q);
174
175 return 0;
176}
177EXPORT_SYMBOL_GPL(sas_unregister_ha);
178
179static int sas_get_linkerrors(struct sas_phy *phy)
180{
181 if (scsi_is_sas_phy_local(phy)) {
182 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
183 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
184 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
185 struct sas_internal *i =
186 to_sas_internal(sas_ha->shost->transportt);
187
188 return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
189 }
190
191 return sas_smp_get_phy_events(phy);
192}
193
194int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
195{
196 struct domain_device *dev = NULL;
197
198 /* try to route user requested link resets through libata */
199 if (asd_phy->port)
200 dev = asd_phy->port->port_dev;
201
202 /* validate that dev has been probed */
203 if (dev)
204 dev = sas_find_dev_by_rphy(dev->rphy);
205
206 if (dev && dev_is_sata(dev)) {
207 sas_ata_schedule_reset(dev);
208 sas_ata_wait_eh(dev);
209 return 0;
210 }
211
212 return -ENODEV;
213}
214
215/*
216 * transport_sas_phy_reset - reset a phy and permit libata to manage the link
217 *
218 * phy reset request via sysfs in host workqueue context so we know we
219 * can block on eh and safely traverse the domain_device topology
220 */
221static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
222{
223 enum phy_func reset_type;
224
225 if (hard_reset)
226 reset_type = PHY_FUNC_HARD_RESET;
227 else
228 reset_type = PHY_FUNC_LINK_RESET;
229
230 if (scsi_is_sas_phy_local(phy)) {
231 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
232 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
233 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
234 struct sas_internal *i =
235 to_sas_internal(sas_ha->shost->transportt);
236
237 if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
238 return 0;
239 return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
240 } else {
241 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
242 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
243 struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
244
245 if (ata_dev && !hard_reset) {
246 sas_ata_schedule_reset(ata_dev);
247 sas_ata_wait_eh(ata_dev);
248 return 0;
249 } else
250 return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
251 }
252}
253
254int sas_phy_enable(struct sas_phy *phy, int enable)
255{
256 int ret;
257 enum phy_func cmd;
258
259 if (enable)
260 cmd = PHY_FUNC_LINK_RESET;
261 else
262 cmd = PHY_FUNC_DISABLE;
263
264 if (scsi_is_sas_phy_local(phy)) {
265 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
266 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
267 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
268 struct sas_internal *i =
269 to_sas_internal(sas_ha->shost->transportt);
270
271 if (enable)
272 ret = transport_sas_phy_reset(phy, 0);
273 else
274 ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
275 } else {
276 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
277 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
278
279 if (enable)
280 ret = transport_sas_phy_reset(phy, 0);
281 else
282 ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
283 }
284 return ret;
285}
286EXPORT_SYMBOL_GPL(sas_phy_enable);
287
288int 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->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}
316EXPORT_SYMBOL_GPL(sas_phy_reset);
317
318static int sas_set_phy_speed(struct sas_phy *phy,
319 struct sas_phy_linkrates *rates)
320{
321 int ret;
322
323 if ((rates->minimum_linkrate &&
324 rates->minimum_linkrate > phy->maximum_linkrate) ||
325 (rates->maximum_linkrate &&
326 rates->maximum_linkrate < phy->minimum_linkrate))
327 return -EINVAL;
328
329 if (rates->minimum_linkrate &&
330 rates->minimum_linkrate < phy->minimum_linkrate_hw)
331 rates->minimum_linkrate = phy->minimum_linkrate_hw;
332
333 if (rates->maximum_linkrate &&
334 rates->maximum_linkrate > phy->maximum_linkrate_hw)
335 rates->maximum_linkrate = phy->maximum_linkrate_hw;
336
337 if (scsi_is_sas_phy_local(phy)) {
338 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
339 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
340 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
341 struct sas_internal *i =
342 to_sas_internal(sas_ha->shost->transportt);
343
344 ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
345 rates);
346 } else {
347 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
348 struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
349 ret = sas_smp_phy_control(ddev, phy->number,
350 PHY_FUNC_LINK_RESET, rates);
351
352 }
353
354 return ret;
355}
356
357void sas_prep_resume_ha(struct sas_ha_struct *ha)
358{
359 int i;
360
361 set_bit(SAS_HA_REGISTERED, &ha->state);
362 set_bit(SAS_HA_RESUMING, &ha->state);
363
364 /* clear out any stale link events/data from the suspension path */
365 for (i = 0; i < ha->num_phys; i++) {
366 struct asd_sas_phy *phy = ha->sas_phy[i];
367
368 memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
369 phy->frame_rcvd_size = 0;
370 }
371}
372EXPORT_SYMBOL(sas_prep_resume_ha);
373
374static 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
388static void sas_resume_insert_broadcast_ha(struct sas_ha_struct *ha)
389{
390 int i;
391
392 for (i = 0; i < ha->num_phys; i++) {
393 struct asd_sas_port *port = ha->sas_port[i];
394 struct domain_device *dev = port->port_dev;
395
396 if (dev && dev_is_expander(dev->dev_type)) {
397 struct asd_sas_phy *first_phy;
398
399 spin_lock(&port->phy_list_lock);
400 first_phy = list_first_entry_or_null(
401 &port->phy_list, struct asd_sas_phy,
402 port_phy_el);
403 spin_unlock(&port->phy_list_lock);
404
405 if (first_phy)
406 sas_notify_port_event(first_phy,
407 PORTE_BROADCAST_RCVD, GFP_KERNEL);
408 }
409 }
410}
411
412static void _sas_resume_ha(struct sas_ha_struct *ha, bool drain)
413{
414 const unsigned long tmo = msecs_to_jiffies(25000);
415 int i;
416
417 /* deform ports on phys that did not resume
418 * at this point we may be racing the phy coming back (as posted
419 * by the lldd). So we post the event and once we are in the
420 * libsas context check that the phy remains suspended before
421 * tearing it down.
422 */
423 i = phys_suspended(ha);
424 if (i)
425 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
426 i, i > 1 ? "s" : "");
427 wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
428 for (i = 0; i < ha->num_phys; i++) {
429 struct asd_sas_phy *phy = ha->sas_phy[i];
430
431 if (phy->suspended) {
432 dev_warn(&phy->phy->dev, "resume timeout\n");
433 sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT,
434 GFP_KERNEL);
435 }
436 }
437
438 /* all phys are back up or timed out, turn on i/o so we can
439 * flush out disks that did not return
440 */
441 scsi_unblock_requests(ha->shost);
442 if (drain)
443 sas_drain_work(ha);
444 clear_bit(SAS_HA_RESUMING, &ha->state);
445
446 sas_queue_deferred_work(ha);
447 /* send event PORTE_BROADCAST_RCVD to identify some new inserted
448 * disks for expander
449 */
450 sas_resume_insert_broadcast_ha(ha);
451}
452
453void sas_resume_ha(struct sas_ha_struct *ha)
454{
455 _sas_resume_ha(ha, true);
456}
457EXPORT_SYMBOL(sas_resume_ha);
458
459/* A no-sync variant, which does not call sas_drain_ha(). */
460void sas_resume_ha_no_sync(struct sas_ha_struct *ha)
461{
462 _sas_resume_ha(ha, false);
463}
464EXPORT_SYMBOL(sas_resume_ha_no_sync);
465
466void sas_suspend_ha(struct sas_ha_struct *ha)
467{
468 int i;
469
470 sas_disable_events(ha);
471 scsi_block_requests(ha->shost);
472 for (i = 0; i < ha->num_phys; i++) {
473 struct asd_sas_port *port = ha->sas_port[i];
474
475 sas_discover_event(port, DISCE_SUSPEND);
476 }
477
478 /* flush suspend events while unregistered */
479 mutex_lock(&ha->drain_mutex);
480 __sas_drain_work(ha);
481 mutex_unlock(&ha->drain_mutex);
482}
483EXPORT_SYMBOL(sas_suspend_ha);
484
485static void sas_phy_release(struct sas_phy *phy)
486{
487 kfree(phy->hostdata);
488 phy->hostdata = NULL;
489}
490
491static void phy_reset_work(struct work_struct *work)
492{
493 struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
494
495 d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
496}
497
498static void phy_enable_work(struct work_struct *work)
499{
500 struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
501
502 d->enable_result = sas_phy_enable(d->phy, d->enable);
503}
504
505static int sas_phy_setup(struct sas_phy *phy)
506{
507 struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
508
509 if (!d)
510 return -ENOMEM;
511
512 mutex_init(&d->event_lock);
513 INIT_SAS_WORK(&d->reset_work, phy_reset_work);
514 INIT_SAS_WORK(&d->enable_work, phy_enable_work);
515 d->phy = phy;
516 phy->hostdata = d;
517
518 return 0;
519}
520
521static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
522{
523 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
524 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
525 struct sas_phy_data *d = phy->hostdata;
526 int rc;
527
528 if (!d)
529 return -ENOMEM;
530
531 pm_runtime_get_sync(ha->dev);
532 /* libsas workqueue coordinates ata-eh reset with discovery */
533 mutex_lock(&d->event_lock);
534 d->reset_result = 0;
535 d->hard_reset = hard_reset;
536
537 spin_lock_irq(&ha->lock);
538 sas_queue_work(ha, &d->reset_work);
539 spin_unlock_irq(&ha->lock);
540
541 rc = sas_drain_work(ha);
542 if (rc == 0)
543 rc = d->reset_result;
544 mutex_unlock(&d->event_lock);
545 pm_runtime_put_sync(ha->dev);
546
547 return rc;
548}
549
550static int queue_phy_enable(struct sas_phy *phy, int enable)
551{
552 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
553 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
554 struct sas_phy_data *d = phy->hostdata;
555 int rc;
556
557 if (!d)
558 return -ENOMEM;
559
560 pm_runtime_get_sync(ha->dev);
561 /* libsas workqueue coordinates ata-eh reset with discovery */
562 mutex_lock(&d->event_lock);
563 d->enable_result = 0;
564 d->enable = enable;
565
566 spin_lock_irq(&ha->lock);
567 sas_queue_work(ha, &d->enable_work);
568 spin_unlock_irq(&ha->lock);
569
570 rc = sas_drain_work(ha);
571 if (rc == 0)
572 rc = d->enable_result;
573 mutex_unlock(&d->event_lock);
574 pm_runtime_put_sync(ha->dev);
575
576 return rc;
577}
578
579static struct sas_function_template sft = {
580 .phy_enable = queue_phy_enable,
581 .phy_reset = queue_phy_reset,
582 .phy_setup = sas_phy_setup,
583 .phy_release = sas_phy_release,
584 .set_phy_speed = sas_set_phy_speed,
585 .get_linkerrors = sas_get_linkerrors,
586 .smp_handler = sas_smp_handler,
587};
588
589static inline ssize_t phy_event_threshold_show(struct device *dev,
590 struct device_attribute *attr, char *buf)
591{
592 struct Scsi_Host *shost = class_to_shost(dev);
593 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
594
595 return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
596}
597
598static inline ssize_t phy_event_threshold_store(struct device *dev,
599 struct device_attribute *attr,
600 const char *buf, size_t count)
601{
602 struct Scsi_Host *shost = class_to_shost(dev);
603 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
604
605 sha->event_thres = simple_strtol(buf, NULL, 10);
606
607 /* threshold cannot be set too small */
608 if (sha->event_thres < 32)
609 sha->event_thres = 32;
610
611 return count;
612}
613
614DEVICE_ATTR(phy_event_threshold,
615 S_IRUGO|S_IWUSR,
616 phy_event_threshold_show,
617 phy_event_threshold_store);
618EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
619
620struct scsi_transport_template *
621sas_domain_attach_transport(struct sas_domain_function_template *dft)
622{
623 struct scsi_transport_template *stt = sas_attach_transport(&sft);
624 struct sas_internal *i;
625
626 if (!stt)
627 return stt;
628
629 i = to_sas_internal(stt);
630 i->dft = dft;
631 stt->create_work_queue = 1;
632 stt->eh_strategy_handler = sas_scsi_recover_host;
633
634 return stt;
635}
636EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
637
638struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy,
639 gfp_t gfp_flags)
640{
641 struct asd_sas_event *event;
642 struct sas_ha_struct *sas_ha = phy->ha;
643 struct sas_internal *i =
644 to_sas_internal(sas_ha->shost->transportt);
645
646 event = kmem_cache_zalloc(sas_event_cache, gfp_flags);
647 if (!event)
648 return NULL;
649
650 atomic_inc(&phy->event_nr);
651
652 if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
653 if (i->dft->lldd_control_phy) {
654 if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
655 pr_notice("The phy%d bursting events, shut it down.\n",
656 phy->id);
657 sas_notify_phy_event(phy, PHYE_SHUTDOWN,
658 gfp_flags);
659 }
660 } else {
661 /* Do not support PHY control, stop allocating events */
662 WARN_ONCE(1, "PHY control not supported.\n");
663 kmem_cache_free(sas_event_cache, event);
664 atomic_dec(&phy->event_nr);
665 event = NULL;
666 }
667 }
668
669 return event;
670}
671
672void sas_free_event(struct asd_sas_event *event)
673{
674 struct asd_sas_phy *phy = event->phy;
675
676 kmem_cache_free(sas_event_cache, event);
677 atomic_dec(&phy->event_nr);
678}
679
680/* ---------- SAS Class register/unregister ---------- */
681
682static int __init sas_class_init(void)
683{
684 sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
685 if (!sas_task_cache)
686 goto out;
687
688 sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN);
689 if (!sas_event_cache)
690 goto free_task_kmem;
691
692 return 0;
693free_task_kmem:
694 kmem_cache_destroy(sas_task_cache);
695out:
696 return -ENOMEM;
697}
698
699static void __exit sas_class_exit(void)
700{
701 kmem_cache_destroy(sas_task_cache);
702 kmem_cache_destroy(sas_event_cache);
703}
704
705MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
706MODULE_DESCRIPTION("SAS Transport Layer");
707MODULE_LICENSE("GPL v2");
708
709module_init(sas_class_init);
710module_exit(sas_class_exit);
711
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Serial Attached SCSI (SAS) Transport Layer initialization
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/module.h>
10#include <linux/slab.h>
11#include <linux/init.h>
12#include <linux/device.h>
13#include <linux/spinlock.h>
14#include <scsi/sas_ata.h>
15#include <scsi/scsi_host.h>
16#include <scsi/scsi_device.h>
17#include <scsi/scsi_transport.h>
18#include <scsi/scsi_transport_sas.h>
19
20#include "sas_internal.h"
21
22#include "../scsi_sas_internal.h"
23
24static struct kmem_cache *sas_task_cache;
25static struct kmem_cache *sas_event_cache;
26
27struct sas_task *sas_alloc_task(gfp_t flags)
28{
29 struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
30
31 if (task) {
32 spin_lock_init(&task->task_state_lock);
33 task->task_state_flags = SAS_TASK_STATE_PENDING;
34 }
35
36 return task;
37}
38EXPORT_SYMBOL_GPL(sas_alloc_task);
39
40struct sas_task *sas_alloc_slow_task(gfp_t flags)
41{
42 struct sas_task *task = sas_alloc_task(flags);
43 struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
44
45 if (!task || !slow) {
46 if (task)
47 kmem_cache_free(sas_task_cache, task);
48 kfree(slow);
49 return NULL;
50 }
51
52 task->slow_task = slow;
53 slow->task = task;
54 timer_setup(&slow->timer, NULL, 0);
55 init_completion(&slow->completion);
56
57 return task;
58}
59EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
60
61void sas_free_task(struct sas_task *task)
62{
63 if (task) {
64 kfree(task->slow_task);
65 kmem_cache_free(sas_task_cache, task);
66 }
67}
68EXPORT_SYMBOL_GPL(sas_free_task);
69
70/*------------ SAS addr hash -----------*/
71void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
72{
73 const u32 poly = 0x00DB2777;
74 u32 r = 0;
75 int i;
76
77 for (i = 0; i < SAS_ADDR_SIZE; i++) {
78 int b;
79
80 for (b = (SAS_ADDR_SIZE - 1); b >= 0; b--) {
81 r <<= 1;
82 if ((1 << b) & sas_addr[i]) {
83 if (!(r & 0x01000000))
84 r ^= poly;
85 } else if (r & 0x01000000) {
86 r ^= poly;
87 }
88 }
89 }
90
91 hashed[0] = (r >> 16) & 0xFF;
92 hashed[1] = (r >> 8) & 0xFF;
93 hashed[2] = r & 0xFF;
94}
95
96int sas_register_ha(struct sas_ha_struct *sas_ha)
97{
98 char name[64];
99 int error = 0;
100
101 mutex_init(&sas_ha->disco_mutex);
102 spin_lock_init(&sas_ha->phy_port_lock);
103 sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
104
105 set_bit(SAS_HA_REGISTERED, &sas_ha->state);
106 spin_lock_init(&sas_ha->lock);
107 mutex_init(&sas_ha->drain_mutex);
108 init_waitqueue_head(&sas_ha->eh_wait_q);
109 INIT_LIST_HEAD(&sas_ha->defer_q);
110 INIT_LIST_HEAD(&sas_ha->eh_dev_q);
111
112 sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
113
114 error = sas_register_phys(sas_ha);
115 if (error) {
116 pr_notice("couldn't register sas phys:%d\n", error);
117 return error;
118 }
119
120 error = sas_register_ports(sas_ha);
121 if (error) {
122 pr_notice("couldn't register sas ports:%d\n", error);
123 goto Undo_phys;
124 }
125
126 error = -ENOMEM;
127 snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev));
128 sas_ha->event_q = create_singlethread_workqueue(name);
129 if (!sas_ha->event_q)
130 goto Undo_ports;
131
132 snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev));
133 sas_ha->disco_q = create_singlethread_workqueue(name);
134 if (!sas_ha->disco_q)
135 goto Undo_event_q;
136
137 INIT_LIST_HEAD(&sas_ha->eh_done_q);
138 INIT_LIST_HEAD(&sas_ha->eh_ata_q);
139
140 return 0;
141
142Undo_event_q:
143 destroy_workqueue(sas_ha->event_q);
144Undo_ports:
145 sas_unregister_ports(sas_ha);
146Undo_phys:
147
148 return error;
149}
150
151static void sas_disable_events(struct sas_ha_struct *sas_ha)
152{
153 /* Set the state to unregistered to avoid further unchained
154 * events to be queued, and flush any in-progress drainers
155 */
156 mutex_lock(&sas_ha->drain_mutex);
157 spin_lock_irq(&sas_ha->lock);
158 clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
159 spin_unlock_irq(&sas_ha->lock);
160 __sas_drain_work(sas_ha);
161 mutex_unlock(&sas_ha->drain_mutex);
162}
163
164int sas_unregister_ha(struct sas_ha_struct *sas_ha)
165{
166 sas_disable_events(sas_ha);
167 sas_unregister_ports(sas_ha);
168
169 /* flush unregistration work */
170 mutex_lock(&sas_ha->drain_mutex);
171 __sas_drain_work(sas_ha);
172 mutex_unlock(&sas_ha->drain_mutex);
173
174 destroy_workqueue(sas_ha->disco_q);
175 destroy_workqueue(sas_ha->event_q);
176
177 return 0;
178}
179
180static 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
195int 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 */
222static 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
255static 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
288int 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
317int 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
356void 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->frame_rcvd_size = 0;
368 }
369}
370EXPORT_SYMBOL(sas_prep_resume_ha);
371
372static int phys_suspended(struct sas_ha_struct *ha)
373{
374 int i, rc = 0;
375
376 for (i = 0; i < ha->num_phys; i++) {
377 struct asd_sas_phy *phy = ha->sas_phy[i];
378
379 if (phy->suspended)
380 rc++;
381 }
382
383 return rc;
384}
385
386void sas_resume_ha(struct sas_ha_struct *ha)
387{
388 const unsigned long tmo = msecs_to_jiffies(25000);
389 int i;
390
391 /* deform ports on phys that did not resume
392 * at this point we may be racing the phy coming back (as posted
393 * by the lldd). So we post the event and once we are in the
394 * libsas context check that the phy remains suspended before
395 * tearing it down.
396 */
397 i = phys_suspended(ha);
398 if (i)
399 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
400 i, i > 1 ? "s" : "");
401 wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
402 for (i = 0; i < ha->num_phys; i++) {
403 struct asd_sas_phy *phy = ha->sas_phy[i];
404
405 if (phy->suspended) {
406 dev_warn(&phy->phy->dev, "resume timeout\n");
407 sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT,
408 GFP_KERNEL);
409 }
410 }
411
412 /* all phys are back up or timed out, turn on i/o so we can
413 * flush out disks that did not return
414 */
415 scsi_unblock_requests(ha->core.shost);
416 sas_drain_work(ha);
417}
418EXPORT_SYMBOL(sas_resume_ha);
419
420void sas_suspend_ha(struct sas_ha_struct *ha)
421{
422 int i;
423
424 sas_disable_events(ha);
425 scsi_block_requests(ha->core.shost);
426 for (i = 0; i < ha->num_phys; i++) {
427 struct asd_sas_port *port = ha->sas_port[i];
428
429 sas_discover_event(port, DISCE_SUSPEND);
430 }
431
432 /* flush suspend events while unregistered */
433 mutex_lock(&ha->drain_mutex);
434 __sas_drain_work(ha);
435 mutex_unlock(&ha->drain_mutex);
436}
437EXPORT_SYMBOL(sas_suspend_ha);
438
439static void sas_phy_release(struct sas_phy *phy)
440{
441 kfree(phy->hostdata);
442 phy->hostdata = NULL;
443}
444
445static void phy_reset_work(struct work_struct *work)
446{
447 struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
448
449 d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
450}
451
452static void phy_enable_work(struct work_struct *work)
453{
454 struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
455
456 d->enable_result = sas_phy_enable(d->phy, d->enable);
457}
458
459static int sas_phy_setup(struct sas_phy *phy)
460{
461 struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
462
463 if (!d)
464 return -ENOMEM;
465
466 mutex_init(&d->event_lock);
467 INIT_SAS_WORK(&d->reset_work, phy_reset_work);
468 INIT_SAS_WORK(&d->enable_work, phy_enable_work);
469 d->phy = phy;
470 phy->hostdata = d;
471
472 return 0;
473}
474
475static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
476{
477 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
478 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
479 struct sas_phy_data *d = phy->hostdata;
480 int rc;
481
482 if (!d)
483 return -ENOMEM;
484
485 /* libsas workqueue coordinates ata-eh reset with discovery */
486 mutex_lock(&d->event_lock);
487 d->reset_result = 0;
488 d->hard_reset = hard_reset;
489
490 spin_lock_irq(&ha->lock);
491 sas_queue_work(ha, &d->reset_work);
492 spin_unlock_irq(&ha->lock);
493
494 rc = sas_drain_work(ha);
495 if (rc == 0)
496 rc = d->reset_result;
497 mutex_unlock(&d->event_lock);
498
499 return rc;
500}
501
502static int queue_phy_enable(struct sas_phy *phy, int enable)
503{
504 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
505 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
506 struct sas_phy_data *d = phy->hostdata;
507 int rc;
508
509 if (!d)
510 return -ENOMEM;
511
512 /* libsas workqueue coordinates ata-eh reset with discovery */
513 mutex_lock(&d->event_lock);
514 d->enable_result = 0;
515 d->enable = enable;
516
517 spin_lock_irq(&ha->lock);
518 sas_queue_work(ha, &d->enable_work);
519 spin_unlock_irq(&ha->lock);
520
521 rc = sas_drain_work(ha);
522 if (rc == 0)
523 rc = d->enable_result;
524 mutex_unlock(&d->event_lock);
525
526 return rc;
527}
528
529static struct sas_function_template sft = {
530 .phy_enable = queue_phy_enable,
531 .phy_reset = queue_phy_reset,
532 .phy_setup = sas_phy_setup,
533 .phy_release = sas_phy_release,
534 .set_phy_speed = sas_set_phy_speed,
535 .get_linkerrors = sas_get_linkerrors,
536 .smp_handler = sas_smp_handler,
537};
538
539static inline ssize_t phy_event_threshold_show(struct device *dev,
540 struct device_attribute *attr, char *buf)
541{
542 struct Scsi_Host *shost = class_to_shost(dev);
543 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
544
545 return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
546}
547
548static inline ssize_t phy_event_threshold_store(struct device *dev,
549 struct device_attribute *attr,
550 const char *buf, size_t count)
551{
552 struct Scsi_Host *shost = class_to_shost(dev);
553 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
554
555 sha->event_thres = simple_strtol(buf, NULL, 10);
556
557 /* threshold cannot be set too small */
558 if (sha->event_thres < 32)
559 sha->event_thres = 32;
560
561 return count;
562}
563
564DEVICE_ATTR(phy_event_threshold,
565 S_IRUGO|S_IWUSR,
566 phy_event_threshold_show,
567 phy_event_threshold_store);
568EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
569
570struct scsi_transport_template *
571sas_domain_attach_transport(struct sas_domain_function_template *dft)
572{
573 struct scsi_transport_template *stt = sas_attach_transport(&sft);
574 struct sas_internal *i;
575
576 if (!stt)
577 return stt;
578
579 i = to_sas_internal(stt);
580 i->dft = dft;
581 stt->create_work_queue = 1;
582 stt->eh_strategy_handler = sas_scsi_recover_host;
583
584 return stt;
585}
586EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
587
588struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy,
589 gfp_t gfp_flags)
590{
591 struct asd_sas_event *event;
592 struct sas_ha_struct *sas_ha = phy->ha;
593 struct sas_internal *i =
594 to_sas_internal(sas_ha->core.shost->transportt);
595
596 event = kmem_cache_zalloc(sas_event_cache, gfp_flags);
597 if (!event)
598 return NULL;
599
600 atomic_inc(&phy->event_nr);
601
602 if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
603 if (i->dft->lldd_control_phy) {
604 if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
605 pr_notice("The phy%d bursting events, shut it down.\n",
606 phy->id);
607 sas_notify_phy_event(phy, PHYE_SHUTDOWN,
608 gfp_flags);
609 }
610 } else {
611 /* Do not support PHY control, stop allocating events */
612 WARN_ONCE(1, "PHY control not supported.\n");
613 kmem_cache_free(sas_event_cache, event);
614 atomic_dec(&phy->event_nr);
615 event = NULL;
616 }
617 }
618
619 return event;
620}
621
622void sas_free_event(struct asd_sas_event *event)
623{
624 struct asd_sas_phy *phy = event->phy;
625
626 kmem_cache_free(sas_event_cache, event);
627 atomic_dec(&phy->event_nr);
628}
629
630/* ---------- SAS Class register/unregister ---------- */
631
632static int __init sas_class_init(void)
633{
634 sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
635 if (!sas_task_cache)
636 goto out;
637
638 sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN);
639 if (!sas_event_cache)
640 goto free_task_kmem;
641
642 return 0;
643free_task_kmem:
644 kmem_cache_destroy(sas_task_cache);
645out:
646 return -ENOMEM;
647}
648
649static void __exit sas_class_exit(void)
650{
651 kmem_cache_destroy(sas_task_cache);
652 kmem_cache_destroy(sas_event_cache);
653}
654
655MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
656MODULE_DESCRIPTION("SAS Transport Layer");
657MODULE_LICENSE("GPL v2");
658
659module_init(sas_class_init);
660module_exit(sas_class_exit);
661
662EXPORT_SYMBOL_GPL(sas_register_ha);
663EXPORT_SYMBOL_GPL(sas_unregister_ha);