1 /*
2 * Serial Attached SCSI (SAS) Discover process
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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
23 */
24
25 #include <linux/scatterlist.h>
26 #include <linux/slab.h>
27 #include <linux/async.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_eh.h>
30 #include "sas_internal.h"
31
32 #include <scsi/scsi_transport.h>
33 #include <scsi/scsi_transport_sas.h>
34 #include <scsi/sas_ata.h>
35 #include "../scsi_sas_internal.h"
36
37 /* ---------- Basic task processing for discovery purposes ---------- */
38
sas_init_dev(struct domain_device * dev)39 void sas_init_dev(struct domain_device *dev)
40 {
41 switch (dev->dev_type) {
42 case SAS_END_DEVICE:
43 INIT_LIST_HEAD(&dev->ssp_dev.eh_list_node);
44 break;
45 case SAS_EDGE_EXPANDER_DEVICE:
46 case SAS_FANOUT_EXPANDER_DEVICE:
47 INIT_LIST_HEAD(&dev->ex_dev.children);
48 mutex_init(&dev->ex_dev.cmd_mutex);
49 break;
50 default:
51 break;
52 }
53 }
54
55 /* ---------- Domain device discovery ---------- */
56
57 /**
58 * sas_get_port_device -- Discover devices which caused port creation
59 * @port: pointer to struct sas_port of interest
60 *
61 * Devices directly attached to a HA port, have no parent. This is
62 * how we know they are (domain) "root" devices. All other devices
63 * do, and should have their "parent" pointer set appropriately as
64 * soon as a child device is discovered.
65 */
sas_get_port_device(struct asd_sas_port * port)66 static int sas_get_port_device(struct asd_sas_port *port)
67 {
68 struct asd_sas_phy *phy;
69 struct sas_rphy *rphy;
70 struct domain_device *dev;
71 int rc = -ENODEV;
72
73 dev = sas_alloc_device();
74 if (!dev)
75 return -ENOMEM;
76
77 spin_lock_irq(&port->phy_list_lock);
78 if (list_empty(&port->phy_list)) {
79 spin_unlock_irq(&port->phy_list_lock);
80 sas_put_device(dev);
81 return -ENODEV;
82 }
83 phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
84 spin_lock(&phy->frame_rcvd_lock);
85 memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
86 (size_t)phy->frame_rcvd_size));
87 spin_unlock(&phy->frame_rcvd_lock);
88 spin_unlock_irq(&port->phy_list_lock);
89
90 if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
91 struct dev_to_host_fis *fis =
92 (struct dev_to_host_fis *) dev->frame_rcvd;
93 if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
94 fis->byte_count_low==0x69 && fis->byte_count_high == 0x96
95 && (fis->device & ~0x10) == 0)
96 dev->dev_type = SAS_SATA_PM;
97 else
98 dev->dev_type = SAS_SATA_DEV;
99 dev->tproto = SAS_PROTOCOL_SATA;
100 } else if (port->oob_mode == SAS_OOB_MODE) {
101 struct sas_identify_frame *id =
102 (struct sas_identify_frame *) dev->frame_rcvd;
103 dev->dev_type = id->dev_type;
104 dev->iproto = id->initiator_bits;
105 dev->tproto = id->target_bits;
106 } else {
107 /* If the oob mode is OOB_NOT_CONNECTED, the port is
108 * disconnected due to race with PHY down. We cannot
109 * continue to discover this port
110 */
111 sas_put_device(dev);
112 pr_warn("Port %016llx is disconnected when discovering\n",
113 SAS_ADDR(port->attached_sas_addr));
114 return -ENODEV;
115 }
116
117 sas_init_dev(dev);
118
119 dev->port = port;
120 switch (dev->dev_type) {
121 case SAS_SATA_DEV:
122 rc = sas_ata_init(dev);
123 if (rc) {
124 rphy = NULL;
125 break;
126 }
127 /* fall through */
128 case SAS_END_DEVICE:
129 rphy = sas_end_device_alloc(port->port);
130 break;
131 case SAS_EDGE_EXPANDER_DEVICE:
132 rphy = sas_expander_alloc(port->port,
133 SAS_EDGE_EXPANDER_DEVICE);
134 break;
135 case SAS_FANOUT_EXPANDER_DEVICE:
136 rphy = sas_expander_alloc(port->port,
137 SAS_FANOUT_EXPANDER_DEVICE);
138 break;
139 default:
140 printk("ERROR: Unidentified device type %d\n", dev->dev_type);
141 rphy = NULL;
142 break;
143 }
144
145 if (!rphy) {
146 sas_put_device(dev);
147 return rc;
148 }
149
150 rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
151 memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
152 sas_fill_in_rphy(dev, rphy);
153 sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
154 port->port_dev = dev;
155 dev->linkrate = port->linkrate;
156 dev->min_linkrate = port->linkrate;
157 dev->max_linkrate = port->linkrate;
158 dev->pathways = port->num_phys;
159 memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
160 memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
161 memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
162 port->disc.max_level = 0;
163 sas_device_set_phy(dev, port->port);
164
165 dev->rphy = rphy;
166 get_device(&dev->rphy->dev);
167
168 if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEVICE)
169 list_add_tail(&dev->disco_list_node, &port->disco_list);
170 else {
171 spin_lock_irq(&port->dev_list_lock);
172 list_add_tail(&dev->dev_list_node, &port->dev_list);
173 spin_unlock_irq(&port->dev_list_lock);
174 }
175
176 spin_lock_irq(&port->phy_list_lock);
177 list_for_each_entry(phy, &port->phy_list, port_phy_el)
178 sas_phy_set_target(phy, dev);
179 spin_unlock_irq(&port->phy_list_lock);
180
181 return 0;
182 }
183
184 /* ---------- Discover and Revalidate ---------- */
185
sas_notify_lldd_dev_found(struct domain_device * dev)186 int sas_notify_lldd_dev_found(struct domain_device *dev)
187 {
188 int res = 0;
189 struct sas_ha_struct *sas_ha = dev->port->ha;
190 struct Scsi_Host *shost = sas_ha->core.shost;
191 struct sas_internal *i = to_sas_internal(shost->transportt);
192
193 if (!i->dft->lldd_dev_found)
194 return 0;
195
196 res = i->dft->lldd_dev_found(dev);
197 if (res) {
198 printk("sas: driver on pcidev %s cannot handle "
199 "device %llx, error:%d\n",
200 dev_name(sas_ha->dev),
201 SAS_ADDR(dev->sas_addr), res);
202 }
203 set_bit(SAS_DEV_FOUND, &dev->state);
204 kref_get(&dev->kref);
205 return res;
206 }
207
208
sas_notify_lldd_dev_gone(struct domain_device * dev)209 void sas_notify_lldd_dev_gone(struct domain_device *dev)
210 {
211 struct sas_ha_struct *sas_ha = dev->port->ha;
212 struct Scsi_Host *shost = sas_ha->core.shost;
213 struct sas_internal *i = to_sas_internal(shost->transportt);
214
215 if (!i->dft->lldd_dev_gone)
216 return;
217
218 if (test_and_clear_bit(SAS_DEV_FOUND, &dev->state)) {
219 i->dft->lldd_dev_gone(dev);
220 sas_put_device(dev);
221 }
222 }
223
sas_probe_devices(struct work_struct * work)224 static void sas_probe_devices(struct work_struct *work)
225 {
226 struct domain_device *dev, *n;
227 struct sas_discovery_event *ev = to_sas_discovery_event(work);
228 struct asd_sas_port *port = ev->port;
229
230 clear_bit(DISCE_PROBE, &port->disc.pending);
231
232 /* devices must be domain members before link recovery and probe */
233 list_for_each_entry(dev, &port->disco_list, disco_list_node) {
234 spin_lock_irq(&port->dev_list_lock);
235 list_add_tail(&dev->dev_list_node, &port->dev_list);
236 spin_unlock_irq(&port->dev_list_lock);
237 }
238
239 sas_probe_sata(port);
240
241 list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
242 int err;
243
244 err = sas_rphy_add(dev->rphy);
245 if (err)
246 sas_fail_probe(dev, __func__, err);
247 else
248 list_del_init(&dev->disco_list_node);
249 }
250 }
251
sas_suspend_devices(struct work_struct * work)252 static void sas_suspend_devices(struct work_struct *work)
253 {
254 struct asd_sas_phy *phy;
255 struct domain_device *dev;
256 struct sas_discovery_event *ev = to_sas_discovery_event(work);
257 struct asd_sas_port *port = ev->port;
258 struct Scsi_Host *shost = port->ha->core.shost;
259 struct sas_internal *si = to_sas_internal(shost->transportt);
260
261 clear_bit(DISCE_SUSPEND, &port->disc.pending);
262
263 sas_suspend_sata(port);
264
265 /* lldd is free to forget the domain_device across the
266 * suspension, we force the issue here to keep the reference
267 * counts aligned
268 */
269 list_for_each_entry(dev, &port->dev_list, dev_list_node)
270 sas_notify_lldd_dev_gone(dev);
271
272 /* we are suspending, so we know events are disabled and
273 * phy_list is not being mutated
274 */
275 list_for_each_entry(phy, &port->phy_list, port_phy_el) {
276 if (si->dft->lldd_port_formed)
277 si->dft->lldd_port_deformed(phy);
278 phy->suspended = 1;
279 port->suspended = 1;
280 }
281 }
282
sas_resume_devices(struct work_struct * work)283 static void sas_resume_devices(struct work_struct *work)
284 {
285 struct sas_discovery_event *ev = to_sas_discovery_event(work);
286 struct asd_sas_port *port = ev->port;
287
288 clear_bit(DISCE_RESUME, &port->disc.pending);
289
290 sas_resume_sata(port);
291 }
292
293 /**
294 * sas_discover_end_dev -- discover an end device (SSP, etc)
295 * @end: pointer to domain device of interest
296 *
297 * See comment in sas_discover_sata().
298 */
sas_discover_end_dev(struct domain_device * dev)299 int sas_discover_end_dev(struct domain_device *dev)
300 {
301 int res;
302
303 res = sas_notify_lldd_dev_found(dev);
304 if (res)
305 return res;
306 sas_discover_event(dev->port, DISCE_PROBE);
307
308 return 0;
309 }
310
311 /* ---------- Device registration and unregistration ---------- */
312
sas_free_device(struct kref * kref)313 void sas_free_device(struct kref *kref)
314 {
315 struct domain_device *dev = container_of(kref, typeof(*dev), kref);
316
317 put_device(&dev->rphy->dev);
318 dev->rphy = NULL;
319
320 if (dev->parent)
321 sas_put_device(dev->parent);
322
323 sas_port_put_phy(dev->phy);
324 dev->phy = NULL;
325
326 /* remove the phys and ports, everything else should be gone */
327 if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE || dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
328 kfree(dev->ex_dev.ex_phy);
329
330 if (dev_is_sata(dev) && dev->sata_dev.ap) {
331 ata_sas_port_destroy(dev->sata_dev.ap);
332 dev->sata_dev.ap = NULL;
333 }
334
335 kfree(dev);
336 }
337
sas_unregister_common_dev(struct asd_sas_port * port,struct domain_device * dev)338 static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
339 {
340 struct sas_ha_struct *ha = port->ha;
341
342 sas_notify_lldd_dev_gone(dev);
343 if (!dev->parent)
344 dev->port->port_dev = NULL;
345 else
346 list_del_init(&dev->siblings);
347
348 spin_lock_irq(&port->dev_list_lock);
349 list_del_init(&dev->dev_list_node);
350 if (dev_is_sata(dev))
351 sas_ata_end_eh(dev->sata_dev.ap);
352 spin_unlock_irq(&port->dev_list_lock);
353
354 spin_lock_irq(&ha->lock);
355 if (dev->dev_type == SAS_END_DEVICE &&
356 !list_empty(&dev->ssp_dev.eh_list_node)) {
357 list_del_init(&dev->ssp_dev.eh_list_node);
358 ha->eh_active--;
359 }
360 spin_unlock_irq(&ha->lock);
361
362 sas_put_device(dev);
363 }
364
sas_destruct_devices(struct work_struct * work)365 static void sas_destruct_devices(struct work_struct *work)
366 {
367 struct domain_device *dev, *n;
368 struct sas_discovery_event *ev = to_sas_discovery_event(work);
369 struct asd_sas_port *port = ev->port;
370
371 clear_bit(DISCE_DESTRUCT, &port->disc.pending);
372
373 list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) {
374 list_del_init(&dev->disco_list_node);
375
376 sas_remove_children(&dev->rphy->dev);
377 sas_rphy_delete(dev->rphy);
378 sas_unregister_common_dev(port, dev);
379 }
380 }
381
sas_unregister_dev(struct asd_sas_port * port,struct domain_device * dev)382 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
383 {
384 if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
385 !list_empty(&dev->disco_list_node)) {
386 /* this rphy never saw sas_rphy_add */
387 list_del_init(&dev->disco_list_node);
388 sas_rphy_free(dev->rphy);
389 sas_unregister_common_dev(port, dev);
390 return;
391 }
392
393 if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
394 sas_rphy_unlink(dev->rphy);
395 list_move_tail(&dev->disco_list_node, &port->destroy_list);
396 sas_discover_event(dev->port, DISCE_DESTRUCT);
397 }
398 }
399
sas_unregister_domain_devices(struct asd_sas_port * port,int gone)400 void sas_unregister_domain_devices(struct asd_sas_port *port, int gone)
401 {
402 struct domain_device *dev, *n;
403
404 list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) {
405 if (gone)
406 set_bit(SAS_DEV_GONE, &dev->state);
407 sas_unregister_dev(port, dev);
408 }
409
410 list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
411 sas_unregister_dev(port, dev);
412
413 port->port->rphy = NULL;
414
415 }
416
sas_device_set_phy(struct domain_device * dev,struct sas_port * port)417 void sas_device_set_phy(struct domain_device *dev, struct sas_port *port)
418 {
419 struct sas_ha_struct *ha;
420 struct sas_phy *new_phy;
421
422 if (!dev)
423 return;
424
425 ha = dev->port->ha;
426 new_phy = sas_port_get_phy(port);
427
428 /* pin and record last seen phy */
429 spin_lock_irq(&ha->phy_port_lock);
430 if (new_phy) {
431 sas_port_put_phy(dev->phy);
432 dev->phy = new_phy;
433 }
434 spin_unlock_irq(&ha->phy_port_lock);
435 }
436
437 /* ---------- Discovery and Revalidation ---------- */
438
439 /**
440 * sas_discover_domain -- discover the domain
441 * @port: port to the domain of interest
442 *
443 * NOTE: this process _must_ quit (return) as soon as any connection
444 * errors are encountered. Connection recovery is done elsewhere.
445 * Discover process only interrogates devices in order to discover the
446 * domain.
447 */
sas_discover_domain(struct work_struct * work)448 static void sas_discover_domain(struct work_struct *work)
449 {
450 struct domain_device *dev;
451 int error = 0;
452 struct sas_discovery_event *ev = to_sas_discovery_event(work);
453 struct asd_sas_port *port = ev->port;
454
455 clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
456
457 if (port->port_dev)
458 return;
459
460 error = sas_get_port_device(port);
461 if (error)
462 return;
463 dev = port->port_dev;
464
465 SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
466 task_pid_nr(current));
467
468 switch (dev->dev_type) {
469 case SAS_END_DEVICE:
470 error = sas_discover_end_dev(dev);
471 break;
472 case SAS_EDGE_EXPANDER_DEVICE:
473 case SAS_FANOUT_EXPANDER_DEVICE:
474 error = sas_discover_root_expander(dev);
475 break;
476 case SAS_SATA_DEV:
477 case SAS_SATA_PM:
478 #ifdef CONFIG_SCSI_SAS_ATA
479 error = sas_discover_sata(dev);
480 break;
481 #else
482 SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
483 /* Fall through */
484 #endif
485 default:
486 error = -ENXIO;
487 SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
488 break;
489 }
490
491 if (error) {
492 sas_rphy_free(dev->rphy);
493 list_del_init(&dev->disco_list_node);
494 spin_lock_irq(&port->dev_list_lock);
495 list_del_init(&dev->dev_list_node);
496 spin_unlock_irq(&port->dev_list_lock);
497
498 sas_put_device(dev);
499 port->port_dev = NULL;
500 }
501
502 SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
503 task_pid_nr(current), error);
504 }
505
sas_revalidate_domain(struct work_struct * work)506 static void sas_revalidate_domain(struct work_struct *work)
507 {
508 int res = 0;
509 struct sas_discovery_event *ev = to_sas_discovery_event(work);
510 struct asd_sas_port *port = ev->port;
511 struct sas_ha_struct *ha = port->ha;
512 struct domain_device *ddev = port->port_dev;
513
514 /* prevent revalidation from finding sata links in recovery */
515 mutex_lock(&ha->disco_mutex);
516 if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
517 SAS_DPRINTK("REVALIDATION DEFERRED on port %d, pid:%d\n",
518 port->id, task_pid_nr(current));
519 goto out;
520 }
521
522 clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
523
524 SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
525 task_pid_nr(current));
526
527 if (ddev && (ddev->dev_type == SAS_FANOUT_EXPANDER_DEVICE ||
528 ddev->dev_type == SAS_EDGE_EXPANDER_DEVICE))
529 res = sas_ex_revalidate_domain(ddev);
530
531 SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
532 port->id, task_pid_nr(current), res);
533 out:
534 mutex_unlock(&ha->disco_mutex);
535 }
536
537 /* ---------- Events ---------- */
538
sas_chain_work(struct sas_ha_struct * ha,struct sas_work * sw)539 static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw)
540 {
541 /* chained work is not subject to SA_HA_DRAINING or
542 * SAS_HA_REGISTERED, because it is either submitted in the
543 * workqueue, or known to be submitted from a context that is
544 * not racing against draining
545 */
546 scsi_queue_work(ha->core.shost, &sw->work);
547 }
548
sas_chain_event(int event,unsigned long * pending,struct sas_work * sw,struct sas_ha_struct * ha)549 static void sas_chain_event(int event, unsigned long *pending,
550 struct sas_work *sw,
551 struct sas_ha_struct *ha)
552 {
553 if (!test_and_set_bit(event, pending)) {
554 unsigned long flags;
555
556 spin_lock_irqsave(&ha->lock, flags);
557 sas_chain_work(ha, sw);
558 spin_unlock_irqrestore(&ha->lock, flags);
559 }
560 }
561
sas_discover_event(struct asd_sas_port * port,enum discover_event ev)562 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
563 {
564 struct sas_discovery *disc;
565
566 if (!port)
567 return 0;
568 disc = &port->disc;
569
570 BUG_ON(ev >= DISC_NUM_EVENTS);
571
572 sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
573
574 return 0;
575 }
576
577 /**
578 * sas_init_disc -- initialize the discovery struct in the port
579 * @port: pointer to struct port
580 *
581 * Called when the ports are being initialized.
582 */
sas_init_disc(struct sas_discovery * disc,struct asd_sas_port * port)583 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
584 {
585 int i;
586
587 static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
588 [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
589 [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
590 [DISCE_PROBE] = sas_probe_devices,
591 [DISCE_SUSPEND] = sas_suspend_devices,
592 [DISCE_RESUME] = sas_resume_devices,
593 [DISCE_DESTRUCT] = sas_destruct_devices,
594 };
595
596 disc->pending = 0;
597 for (i = 0; i < DISC_NUM_EVENTS; i++) {
598 INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
599 disc->disc_work[i].port = port;
600 }
601 }
602