1 /*
2  * Serial Attached SCSI (SAS) Expander discovery and configuration
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/blkdev.h>
27 #include <linux/slab.h>
28 #include <asm/unaligned.h>
29 
30 #include "sas_internal.h"
31 
32 #include <scsi/sas_ata.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_transport_sas.h>
35 #include "../scsi_sas_internal.h"
36 
37 static int sas_discover_expander(struct domain_device *dev);
38 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
39 static int sas_configure_phy(struct domain_device *dev, int phy_id,
40 			     u8 *sas_addr, int include);
41 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
42 
43 /* ---------- SMP task management ---------- */
44 
45 static void smp_task_timedout(struct timer_list *t)
46 {
47 	struct sas_task_slow *slow = from_timer(slow, t, timer);
48 	struct sas_task *task = slow->task;
49 	unsigned long flags;
50 
51 	spin_lock_irqsave(&task->task_state_lock, flags);
52 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
53 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
54 		complete(&task->slow_task->completion);
55 	}
56 	spin_unlock_irqrestore(&task->task_state_lock, flags);
57 }
58 
59 static void smp_task_done(struct sas_task *task)
60 {
61 	del_timer(&task->slow_task->timer);
62 	complete(&task->slow_task->completion);
63 }
64 
65 /* Give it some long enough timeout. In seconds. */
66 #define SMP_TIMEOUT 10
67 
68 static int smp_execute_task_sg(struct domain_device *dev,
69 		struct scatterlist *req, struct scatterlist *resp)
70 {
71 	int res, retry;
72 	struct sas_task *task = NULL;
73 	struct sas_internal *i =
74 		to_sas_internal(dev->port->ha->core.shost->transportt);
75 
76 	mutex_lock(&dev->ex_dev.cmd_mutex);
77 	for (retry = 0; retry < 3; retry++) {
78 		if (test_bit(SAS_DEV_GONE, &dev->state)) {
79 			res = -ECOMM;
80 			break;
81 		}
82 
83 		task = sas_alloc_slow_task(GFP_KERNEL);
84 		if (!task) {
85 			res = -ENOMEM;
86 			break;
87 		}
88 		task->dev = dev;
89 		task->task_proto = dev->tproto;
90 		task->smp_task.smp_req = *req;
91 		task->smp_task.smp_resp = *resp;
92 
93 		task->task_done = smp_task_done;
94 
95 		task->slow_task->timer.function = smp_task_timedout;
96 		task->slow_task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
97 		add_timer(&task->slow_task->timer);
98 
99 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
100 
101 		if (res) {
102 			del_timer(&task->slow_task->timer);
103 			pr_notice("executing SMP task failed:%d\n", res);
104 			break;
105 		}
106 
107 		wait_for_completion(&task->slow_task->completion);
108 		res = -ECOMM;
109 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
110 			pr_notice("smp task timed out or aborted\n");
111 			i->dft->lldd_abort_task(task);
112 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
113 				pr_notice("SMP task aborted and not done\n");
114 				break;
115 			}
116 		}
117 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
118 		    task->task_status.stat == SAM_STAT_GOOD) {
119 			res = 0;
120 			break;
121 		}
122 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
123 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
124 			/* no error, but return the number of bytes of
125 			 * underrun */
126 			res = task->task_status.residual;
127 			break;
128 		}
129 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
130 		    task->task_status.stat == SAS_DATA_OVERRUN) {
131 			res = -EMSGSIZE;
132 			break;
133 		}
134 		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
135 		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
136 			break;
137 		else {
138 			pr_notice("%s: task to dev %016llx response: 0x%x status 0x%x\n",
139 				  __func__,
140 				  SAS_ADDR(dev->sas_addr),
141 				  task->task_status.resp,
142 				  task->task_status.stat);
143 			sas_free_task(task);
144 			task = NULL;
145 		}
146 	}
147 	mutex_unlock(&dev->ex_dev.cmd_mutex);
148 
149 	BUG_ON(retry == 3 && task != NULL);
150 	sas_free_task(task);
151 	return res;
152 }
153 
154 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
155 			    void *resp, int resp_size)
156 {
157 	struct scatterlist req_sg;
158 	struct scatterlist resp_sg;
159 
160 	sg_init_one(&req_sg, req, req_size);
161 	sg_init_one(&resp_sg, resp, resp_size);
162 	return smp_execute_task_sg(dev, &req_sg, &resp_sg);
163 }
164 
165 /* ---------- Allocations ---------- */
166 
167 static inline void *alloc_smp_req(int size)
168 {
169 	u8 *p = kzalloc(size, GFP_KERNEL);
170 	if (p)
171 		p[0] = SMP_REQUEST;
172 	return p;
173 }
174 
175 static inline void *alloc_smp_resp(int size)
176 {
177 	return kzalloc(size, GFP_KERNEL);
178 }
179 
180 static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
181 {
182 	switch (phy->routing_attr) {
183 	case TABLE_ROUTING:
184 		if (dev->ex_dev.t2t_supp)
185 			return 'U';
186 		else
187 			return 'T';
188 	case DIRECT_ROUTING:
189 		return 'D';
190 	case SUBTRACTIVE_ROUTING:
191 		return 'S';
192 	default:
193 		return '?';
194 	}
195 }
196 
197 static enum sas_device_type to_dev_type(struct discover_resp *dr)
198 {
199 	/* This is detecting a failure to transmit initial dev to host
200 	 * FIS as described in section J.5 of sas-2 r16
201 	 */
202 	if (dr->attached_dev_type == SAS_PHY_UNUSED && dr->attached_sata_dev &&
203 	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
204 		return SAS_SATA_PENDING;
205 	else
206 		return dr->attached_dev_type;
207 }
208 
209 static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
210 {
211 	enum sas_device_type dev_type;
212 	enum sas_linkrate linkrate;
213 	u8 sas_addr[SAS_ADDR_SIZE];
214 	struct smp_resp *resp = rsp;
215 	struct discover_resp *dr = &resp->disc;
216 	struct sas_ha_struct *ha = dev->port->ha;
217 	struct expander_device *ex = &dev->ex_dev;
218 	struct ex_phy *phy = &ex->ex_phy[phy_id];
219 	struct sas_rphy *rphy = dev->rphy;
220 	bool new_phy = !phy->phy;
221 	char *type;
222 
223 	if (new_phy) {
224 		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
225 			return;
226 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
227 
228 		/* FIXME: error_handling */
229 		BUG_ON(!phy->phy);
230 	}
231 
232 	switch (resp->result) {
233 	case SMP_RESP_PHY_VACANT:
234 		phy->phy_state = PHY_VACANT;
235 		break;
236 	default:
237 		phy->phy_state = PHY_NOT_PRESENT;
238 		break;
239 	case SMP_RESP_FUNC_ACC:
240 		phy->phy_state = PHY_EMPTY; /* do not know yet */
241 		break;
242 	}
243 
244 	/* check if anything important changed to squelch debug */
245 	dev_type = phy->attached_dev_type;
246 	linkrate  = phy->linkrate;
247 	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
248 
249 	/* Handle vacant phy - rest of dr data is not valid so skip it */
250 	if (phy->phy_state == PHY_VACANT) {
251 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
252 		phy->attached_dev_type = SAS_PHY_UNUSED;
253 		if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
254 			phy->phy_id = phy_id;
255 			goto skip;
256 		} else
257 			goto out;
258 	}
259 
260 	phy->attached_dev_type = to_dev_type(dr);
261 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
262 		goto out;
263 	phy->phy_id = phy_id;
264 	phy->linkrate = dr->linkrate;
265 	phy->attached_sata_host = dr->attached_sata_host;
266 	phy->attached_sata_dev  = dr->attached_sata_dev;
267 	phy->attached_sata_ps   = dr->attached_sata_ps;
268 	phy->attached_iproto = dr->iproto << 1;
269 	phy->attached_tproto = dr->tproto << 1;
270 	/* help some expanders that fail to zero sas_address in the 'no
271 	 * device' case
272 	 */
273 	if (phy->attached_dev_type == SAS_PHY_UNUSED ||
274 	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
275 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
276 	else
277 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
278 	phy->attached_phy_id = dr->attached_phy_id;
279 	phy->phy_change_count = dr->change_count;
280 	phy->routing_attr = dr->routing_attr;
281 	phy->virtual = dr->virtual;
282 	phy->last_da_index = -1;
283 
284 	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
285 	phy->phy->identify.device_type = dr->attached_dev_type;
286 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
287 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
288 	if (!phy->attached_tproto && dr->attached_sata_dev)
289 		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
290 	phy->phy->identify.phy_identifier = phy_id;
291 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
292 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
293 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
294 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
295 	phy->phy->negotiated_linkrate = phy->linkrate;
296 	phy->phy->enabled = (phy->linkrate != SAS_PHY_DISABLED);
297 
298  skip:
299 	if (new_phy)
300 		if (sas_phy_add(phy->phy)) {
301 			sas_phy_free(phy->phy);
302 			return;
303 		}
304 
305  out:
306 	switch (phy->attached_dev_type) {
307 	case SAS_SATA_PENDING:
308 		type = "stp pending";
309 		break;
310 	case SAS_PHY_UNUSED:
311 		type = "no device";
312 		break;
313 	case SAS_END_DEVICE:
314 		if (phy->attached_iproto) {
315 			if (phy->attached_tproto)
316 				type = "host+target";
317 			else
318 				type = "host";
319 		} else {
320 			if (dr->attached_sata_dev)
321 				type = "stp";
322 			else
323 				type = "ssp";
324 		}
325 		break;
326 	case SAS_EDGE_EXPANDER_DEVICE:
327 	case SAS_FANOUT_EXPANDER_DEVICE:
328 		type = "smp";
329 		break;
330 	default:
331 		type = "unknown";
332 	}
333 
334 	/* this routine is polled by libata error recovery so filter
335 	 * unimportant messages
336 	 */
337 	if (new_phy || phy->attached_dev_type != dev_type ||
338 	    phy->linkrate != linkrate ||
339 	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
340 		/* pass */;
341 	else
342 		return;
343 
344 	/* if the attached device type changed and ata_eh is active,
345 	 * make sure we run revalidation when eh completes (see:
346 	 * sas_enable_revalidation)
347 	 */
348 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
349 		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
350 
351 	pr_debug("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
352 		 test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
353 		 SAS_ADDR(dev->sas_addr), phy->phy_id,
354 		 sas_route_char(dev, phy), phy->linkrate,
355 		 SAS_ADDR(phy->attached_sas_addr), type);
356 }
357 
358 /* check if we have an existing attached ata device on this expander phy */
359 struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
360 {
361 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
362 	struct domain_device *dev;
363 	struct sas_rphy *rphy;
364 
365 	if (!ex_phy->port)
366 		return NULL;
367 
368 	rphy = ex_phy->port->rphy;
369 	if (!rphy)
370 		return NULL;
371 
372 	dev = sas_find_dev_by_rphy(rphy);
373 
374 	if (dev && dev_is_sata(dev))
375 		return dev;
376 
377 	return NULL;
378 }
379 
380 #define DISCOVER_REQ_SIZE  16
381 #define DISCOVER_RESP_SIZE 56
382 
383 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
384 				      u8 *disc_resp, int single)
385 {
386 	struct discover_resp *dr;
387 	int res;
388 
389 	disc_req[9] = single;
390 
391 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
392 			       disc_resp, DISCOVER_RESP_SIZE);
393 	if (res)
394 		return res;
395 	dr = &((struct smp_resp *)disc_resp)->disc;
396 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
397 		pr_notice("Found loopback topology, just ignore it!\n");
398 		return 0;
399 	}
400 	sas_set_ex_phy(dev, single, disc_resp);
401 	return 0;
402 }
403 
404 int sas_ex_phy_discover(struct domain_device *dev, int single)
405 {
406 	struct expander_device *ex = &dev->ex_dev;
407 	int  res = 0;
408 	u8   *disc_req;
409 	u8   *disc_resp;
410 
411 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
412 	if (!disc_req)
413 		return -ENOMEM;
414 
415 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
416 	if (!disc_resp) {
417 		kfree(disc_req);
418 		return -ENOMEM;
419 	}
420 
421 	disc_req[1] = SMP_DISCOVER;
422 
423 	if (0 <= single && single < ex->num_phys) {
424 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
425 	} else {
426 		int i;
427 
428 		for (i = 0; i < ex->num_phys; i++) {
429 			res = sas_ex_phy_discover_helper(dev, disc_req,
430 							 disc_resp, i);
431 			if (res)
432 				goto out_err;
433 		}
434 	}
435 out_err:
436 	kfree(disc_resp);
437 	kfree(disc_req);
438 	return res;
439 }
440 
441 static int sas_expander_discover(struct domain_device *dev)
442 {
443 	struct expander_device *ex = &dev->ex_dev;
444 	int res = -ENOMEM;
445 
446 	ex->ex_phy = kcalloc(ex->num_phys, sizeof(*ex->ex_phy), GFP_KERNEL);
447 	if (!ex->ex_phy)
448 		return -ENOMEM;
449 
450 	res = sas_ex_phy_discover(dev, -1);
451 	if (res)
452 		goto out_err;
453 
454 	return 0;
455  out_err:
456 	kfree(ex->ex_phy);
457 	ex->ex_phy = NULL;
458 	return res;
459 }
460 
461 #define MAX_EXPANDER_PHYS 128
462 
463 static void ex_assign_report_general(struct domain_device *dev,
464 					    struct smp_resp *resp)
465 {
466 	struct report_general_resp *rg = &resp->rg;
467 
468 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
469 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
470 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
471 	dev->ex_dev.t2t_supp = rg->t2t_supp;
472 	dev->ex_dev.conf_route_table = rg->conf_route_table;
473 	dev->ex_dev.configuring = rg->configuring;
474 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
475 }
476 
477 #define RG_REQ_SIZE   8
478 #define RG_RESP_SIZE 32
479 
480 static int sas_ex_general(struct domain_device *dev)
481 {
482 	u8 *rg_req;
483 	struct smp_resp *rg_resp;
484 	int res;
485 	int i;
486 
487 	rg_req = alloc_smp_req(RG_REQ_SIZE);
488 	if (!rg_req)
489 		return -ENOMEM;
490 
491 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
492 	if (!rg_resp) {
493 		kfree(rg_req);
494 		return -ENOMEM;
495 	}
496 
497 	rg_req[1] = SMP_REPORT_GENERAL;
498 
499 	for (i = 0; i < 5; i++) {
500 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
501 				       RG_RESP_SIZE);
502 
503 		if (res) {
504 			pr_notice("RG to ex %016llx failed:0x%x\n",
505 				  SAS_ADDR(dev->sas_addr), res);
506 			goto out;
507 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
508 			pr_debug("RG:ex %016llx returned SMP result:0x%x\n",
509 				 SAS_ADDR(dev->sas_addr), rg_resp->result);
510 			res = rg_resp->result;
511 			goto out;
512 		}
513 
514 		ex_assign_report_general(dev, rg_resp);
515 
516 		if (dev->ex_dev.configuring) {
517 			pr_debug("RG: ex %llx self-configuring...\n",
518 				 SAS_ADDR(dev->sas_addr));
519 			schedule_timeout_interruptible(5*HZ);
520 		} else
521 			break;
522 	}
523 out:
524 	kfree(rg_req);
525 	kfree(rg_resp);
526 	return res;
527 }
528 
529 static void ex_assign_manuf_info(struct domain_device *dev, void
530 					*_mi_resp)
531 {
532 	u8 *mi_resp = _mi_resp;
533 	struct sas_rphy *rphy = dev->rphy;
534 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
535 
536 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
537 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
538 	memcpy(edev->product_rev, mi_resp + 36,
539 	       SAS_EXPANDER_PRODUCT_REV_LEN);
540 
541 	if (mi_resp[8] & 1) {
542 		memcpy(edev->component_vendor_id, mi_resp + 40,
543 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
544 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
545 		edev->component_revision_id = mi_resp[50];
546 	}
547 }
548 
549 #define MI_REQ_SIZE   8
550 #define MI_RESP_SIZE 64
551 
552 static int sas_ex_manuf_info(struct domain_device *dev)
553 {
554 	u8 *mi_req;
555 	u8 *mi_resp;
556 	int res;
557 
558 	mi_req = alloc_smp_req(MI_REQ_SIZE);
559 	if (!mi_req)
560 		return -ENOMEM;
561 
562 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
563 	if (!mi_resp) {
564 		kfree(mi_req);
565 		return -ENOMEM;
566 	}
567 
568 	mi_req[1] = SMP_REPORT_MANUF_INFO;
569 
570 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
571 	if (res) {
572 		pr_notice("MI: ex %016llx failed:0x%x\n",
573 			  SAS_ADDR(dev->sas_addr), res);
574 		goto out;
575 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
576 		pr_debug("MI ex %016llx returned SMP result:0x%x\n",
577 			 SAS_ADDR(dev->sas_addr), mi_resp[2]);
578 		goto out;
579 	}
580 
581 	ex_assign_manuf_info(dev, mi_resp);
582 out:
583 	kfree(mi_req);
584 	kfree(mi_resp);
585 	return res;
586 }
587 
588 #define PC_REQ_SIZE  44
589 #define PC_RESP_SIZE 8
590 
591 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
592 			enum phy_func phy_func,
593 			struct sas_phy_linkrates *rates)
594 {
595 	u8 *pc_req;
596 	u8 *pc_resp;
597 	int res;
598 
599 	pc_req = alloc_smp_req(PC_REQ_SIZE);
600 	if (!pc_req)
601 		return -ENOMEM;
602 
603 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
604 	if (!pc_resp) {
605 		kfree(pc_req);
606 		return -ENOMEM;
607 	}
608 
609 	pc_req[1] = SMP_PHY_CONTROL;
610 	pc_req[9] = phy_id;
611 	pc_req[10]= phy_func;
612 	if (rates) {
613 		pc_req[32] = rates->minimum_linkrate << 4;
614 		pc_req[33] = rates->maximum_linkrate << 4;
615 	}
616 
617 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
618 	if (res) {
619 		pr_err("ex %016llx phy%02d PHY control failed: %d\n",
620 		       SAS_ADDR(dev->sas_addr), phy_id, res);
621 	} else if (pc_resp[2] != SMP_RESP_FUNC_ACC) {
622 		pr_err("ex %016llx phy%02d PHY control failed: function result 0x%x\n",
623 		       SAS_ADDR(dev->sas_addr), phy_id, pc_resp[2]);
624 		res = pc_resp[2];
625 	}
626 	kfree(pc_resp);
627 	kfree(pc_req);
628 	return res;
629 }
630 
631 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
632 {
633 	struct expander_device *ex = &dev->ex_dev;
634 	struct ex_phy *phy = &ex->ex_phy[phy_id];
635 
636 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
637 	phy->linkrate = SAS_PHY_DISABLED;
638 }
639 
640 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
641 {
642 	struct expander_device *ex = &dev->ex_dev;
643 	int i;
644 
645 	for (i = 0; i < ex->num_phys; i++) {
646 		struct ex_phy *phy = &ex->ex_phy[i];
647 
648 		if (phy->phy_state == PHY_VACANT ||
649 		    phy->phy_state == PHY_NOT_PRESENT)
650 			continue;
651 
652 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
653 			sas_ex_disable_phy(dev, i);
654 	}
655 }
656 
657 static int sas_dev_present_in_domain(struct asd_sas_port *port,
658 					    u8 *sas_addr)
659 {
660 	struct domain_device *dev;
661 
662 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
663 		return 1;
664 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
665 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
666 			return 1;
667 	}
668 	return 0;
669 }
670 
671 #define RPEL_REQ_SIZE	16
672 #define RPEL_RESP_SIZE	32
673 int sas_smp_get_phy_events(struct sas_phy *phy)
674 {
675 	int res;
676 	u8 *req;
677 	u8 *resp;
678 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
679 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
680 
681 	req = alloc_smp_req(RPEL_REQ_SIZE);
682 	if (!req)
683 		return -ENOMEM;
684 
685 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
686 	if (!resp) {
687 		kfree(req);
688 		return -ENOMEM;
689 	}
690 
691 	req[1] = SMP_REPORT_PHY_ERR_LOG;
692 	req[9] = phy->number;
693 
694 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
695 			            resp, RPEL_RESP_SIZE);
696 
697 	if (res)
698 		goto out;
699 
700 	phy->invalid_dword_count = get_unaligned_be32(&resp[12]);
701 	phy->running_disparity_error_count = get_unaligned_be32(&resp[16]);
702 	phy->loss_of_dword_sync_count = get_unaligned_be32(&resp[20]);
703 	phy->phy_reset_problem_count = get_unaligned_be32(&resp[24]);
704 
705  out:
706 	kfree(req);
707 	kfree(resp);
708 	return res;
709 
710 }
711 
712 #ifdef CONFIG_SCSI_SAS_ATA
713 
714 #define RPS_REQ_SIZE  16
715 #define RPS_RESP_SIZE 60
716 
717 int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
718 			    struct smp_resp *rps_resp)
719 {
720 	int res;
721 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
722 	u8 *resp = (u8 *)rps_resp;
723 
724 	if (!rps_req)
725 		return -ENOMEM;
726 
727 	rps_req[1] = SMP_REPORT_PHY_SATA;
728 	rps_req[9] = phy_id;
729 
730 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
731 			            rps_resp, RPS_RESP_SIZE);
732 
733 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
734 	 * standards cockup here.  sas-2 explicitly specifies the FIS
735 	 * should be encoded so that FIS type is in resp[24].
736 	 * However, some expanders endian reverse this.  Undo the
737 	 * reversal here */
738 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
739 		int i;
740 
741 		for (i = 0; i < 5; i++) {
742 			int j = 24 + (i*4);
743 			u8 a, b;
744 			a = resp[j + 0];
745 			b = resp[j + 1];
746 			resp[j + 0] = resp[j + 3];
747 			resp[j + 1] = resp[j + 2];
748 			resp[j + 2] = b;
749 			resp[j + 3] = a;
750 		}
751 	}
752 
753 	kfree(rps_req);
754 	return res;
755 }
756 #endif
757 
758 static void sas_ex_get_linkrate(struct domain_device *parent,
759 				       struct domain_device *child,
760 				       struct ex_phy *parent_phy)
761 {
762 	struct expander_device *parent_ex = &parent->ex_dev;
763 	struct sas_port *port;
764 	int i;
765 
766 	child->pathways = 0;
767 
768 	port = parent_phy->port;
769 
770 	for (i = 0; i < parent_ex->num_phys; i++) {
771 		struct ex_phy *phy = &parent_ex->ex_phy[i];
772 
773 		if (phy->phy_state == PHY_VACANT ||
774 		    phy->phy_state == PHY_NOT_PRESENT)
775 			continue;
776 
777 		if (SAS_ADDR(phy->attached_sas_addr) ==
778 		    SAS_ADDR(child->sas_addr)) {
779 
780 			child->min_linkrate = min(parent->min_linkrate,
781 						  phy->linkrate);
782 			child->max_linkrate = max(parent->max_linkrate,
783 						  phy->linkrate);
784 			child->pathways++;
785 			sas_port_add_phy(port, phy->phy);
786 		}
787 	}
788 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
789 	child->pathways = min(child->pathways, parent->pathways);
790 }
791 
792 static struct domain_device *sas_ex_discover_end_dev(
793 	struct domain_device *parent, int phy_id)
794 {
795 	struct expander_device *parent_ex = &parent->ex_dev;
796 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
797 	struct domain_device *child = NULL;
798 	struct sas_rphy *rphy;
799 	int res;
800 
801 	if (phy->attached_sata_host || phy->attached_sata_ps)
802 		return NULL;
803 
804 	child = sas_alloc_device();
805 	if (!child)
806 		return NULL;
807 
808 	kref_get(&parent->kref);
809 	child->parent = parent;
810 	child->port   = parent->port;
811 	child->iproto = phy->attached_iproto;
812 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
813 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
814 	if (!phy->port) {
815 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
816 		if (unlikely(!phy->port))
817 			goto out_err;
818 		if (unlikely(sas_port_add(phy->port) != 0)) {
819 			sas_port_free(phy->port);
820 			goto out_err;
821 		}
822 	}
823 	sas_ex_get_linkrate(parent, child, phy);
824 	sas_device_set_phy(child, phy->port);
825 
826 #ifdef CONFIG_SCSI_SAS_ATA
827 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
828 		if (child->linkrate > parent->min_linkrate) {
829 			struct sas_phy *cphy = child->phy;
830 			enum sas_linkrate min_prate = cphy->minimum_linkrate,
831 				parent_min_lrate = parent->min_linkrate,
832 				min_linkrate = (min_prate > parent_min_lrate) ?
833 					       parent_min_lrate : 0;
834 			struct sas_phy_linkrates rates = {
835 				.maximum_linkrate = parent->min_linkrate,
836 				.minimum_linkrate = min_linkrate,
837 			};
838 			int ret;
839 
840 			pr_notice("ex %016llx phy%02d SATA device linkrate > min pathway connection rate, attempting to lower device linkrate\n",
841 				   SAS_ADDR(child->sas_addr), phy_id);
842 			ret = sas_smp_phy_control(parent, phy_id,
843 						  PHY_FUNC_LINK_RESET, &rates);
844 			if (ret) {
845 				pr_err("ex %016llx phy%02d SATA device could not set linkrate (%d)\n",
846 				       SAS_ADDR(child->sas_addr), phy_id, ret);
847 				goto out_free;
848 			}
849 			pr_notice("ex %016llx phy%02d SATA device set linkrate successfully\n",
850 				  SAS_ADDR(child->sas_addr), phy_id);
851 			child->linkrate = child->min_linkrate;
852 		}
853 		res = sas_get_ata_info(child, phy);
854 		if (res)
855 			goto out_free;
856 
857 		sas_init_dev(child);
858 		res = sas_ata_init(child);
859 		if (res)
860 			goto out_free;
861 		rphy = sas_end_device_alloc(phy->port);
862 		if (!rphy)
863 			goto out_free;
864 		rphy->identify.phy_identifier = phy_id;
865 
866 		child->rphy = rphy;
867 		get_device(&rphy->dev);
868 
869 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
870 
871 		res = sas_discover_sata(child);
872 		if (res) {
873 			pr_notice("sas_discover_sata() for device %16llx at %016llx:%02d returned 0x%x\n",
874 				  SAS_ADDR(child->sas_addr),
875 				  SAS_ADDR(parent->sas_addr), phy_id, res);
876 			goto out_list_del;
877 		}
878 	} else
879 #endif
880 	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
881 		child->dev_type = SAS_END_DEVICE;
882 		rphy = sas_end_device_alloc(phy->port);
883 		/* FIXME: error handling */
884 		if (unlikely(!rphy))
885 			goto out_free;
886 		child->tproto = phy->attached_tproto;
887 		sas_init_dev(child);
888 
889 		child->rphy = rphy;
890 		get_device(&rphy->dev);
891 		rphy->identify.phy_identifier = phy_id;
892 		sas_fill_in_rphy(child, rphy);
893 
894 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
895 
896 		res = sas_discover_end_dev(child);
897 		if (res) {
898 			pr_notice("sas_discover_end_dev() for device %16llx at %016llx:%02d returned 0x%x\n",
899 				  SAS_ADDR(child->sas_addr),
900 				  SAS_ADDR(parent->sas_addr), phy_id, res);
901 			goto out_list_del;
902 		}
903 	} else {
904 		pr_notice("target proto 0x%x at %016llx:0x%x not handled\n",
905 			  phy->attached_tproto, SAS_ADDR(parent->sas_addr),
906 			  phy_id);
907 		goto out_free;
908 	}
909 
910 	list_add_tail(&child->siblings, &parent_ex->children);
911 	return child;
912 
913  out_list_del:
914 	sas_rphy_free(child->rphy);
915 	list_del(&child->disco_list_node);
916 	spin_lock_irq(&parent->port->dev_list_lock);
917 	list_del(&child->dev_list_node);
918 	spin_unlock_irq(&parent->port->dev_list_lock);
919  out_free:
920 	sas_port_delete(phy->port);
921  out_err:
922 	phy->port = NULL;
923 	sas_put_device(child);
924 	return NULL;
925 }
926 
927 /* See if this phy is part of a wide port */
928 static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
929 {
930 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
931 	int i;
932 
933 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
934 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
935 
936 		if (ephy == phy)
937 			continue;
938 
939 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
940 			    SAS_ADDR_SIZE) && ephy->port) {
941 			sas_port_add_phy(ephy->port, phy->phy);
942 			phy->port = ephy->port;
943 			phy->phy_state = PHY_DEVICE_DISCOVERED;
944 			return true;
945 		}
946 	}
947 
948 	return false;
949 }
950 
951 static struct domain_device *sas_ex_discover_expander(
952 	struct domain_device *parent, int phy_id)
953 {
954 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
955 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
956 	struct domain_device *child = NULL;
957 	struct sas_rphy *rphy;
958 	struct sas_expander_device *edev;
959 	struct asd_sas_port *port;
960 	int res;
961 
962 	if (phy->routing_attr == DIRECT_ROUTING) {
963 		pr_warn("ex %016llx:%02d:D <--> ex %016llx:0x%x is not allowed\n",
964 			SAS_ADDR(parent->sas_addr), phy_id,
965 			SAS_ADDR(phy->attached_sas_addr),
966 			phy->attached_phy_id);
967 		return NULL;
968 	}
969 	child = sas_alloc_device();
970 	if (!child)
971 		return NULL;
972 
973 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
974 	/* FIXME: better error handling */
975 	BUG_ON(sas_port_add(phy->port) != 0);
976 
977 
978 	switch (phy->attached_dev_type) {
979 	case SAS_EDGE_EXPANDER_DEVICE:
980 		rphy = sas_expander_alloc(phy->port,
981 					  SAS_EDGE_EXPANDER_DEVICE);
982 		break;
983 	case SAS_FANOUT_EXPANDER_DEVICE:
984 		rphy = sas_expander_alloc(phy->port,
985 					  SAS_FANOUT_EXPANDER_DEVICE);
986 		break;
987 	default:
988 		rphy = NULL;	/* shut gcc up */
989 		BUG();
990 	}
991 	port = parent->port;
992 	child->rphy = rphy;
993 	get_device(&rphy->dev);
994 	edev = rphy_to_expander_device(rphy);
995 	child->dev_type = phy->attached_dev_type;
996 	kref_get(&parent->kref);
997 	child->parent = parent;
998 	child->port = port;
999 	child->iproto = phy->attached_iproto;
1000 	child->tproto = phy->attached_tproto;
1001 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
1002 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
1003 	sas_ex_get_linkrate(parent, child, phy);
1004 	edev->level = parent_ex->level + 1;
1005 	parent->port->disc.max_level = max(parent->port->disc.max_level,
1006 					   edev->level);
1007 	sas_init_dev(child);
1008 	sas_fill_in_rphy(child, rphy);
1009 	sas_rphy_add(rphy);
1010 
1011 	spin_lock_irq(&parent->port->dev_list_lock);
1012 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
1013 	spin_unlock_irq(&parent->port->dev_list_lock);
1014 
1015 	res = sas_discover_expander(child);
1016 	if (res) {
1017 		sas_rphy_delete(rphy);
1018 		spin_lock_irq(&parent->port->dev_list_lock);
1019 		list_del(&child->dev_list_node);
1020 		spin_unlock_irq(&parent->port->dev_list_lock);
1021 		sas_put_device(child);
1022 		sas_port_delete(phy->port);
1023 		phy->port = NULL;
1024 		return NULL;
1025 	}
1026 	list_add_tail(&child->siblings, &parent->ex_dev.children);
1027 	return child;
1028 }
1029 
1030 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
1031 {
1032 	struct expander_device *ex = &dev->ex_dev;
1033 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
1034 	struct domain_device *child = NULL;
1035 	int res = 0;
1036 
1037 	/* Phy state */
1038 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
1039 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
1040 			res = sas_ex_phy_discover(dev, phy_id);
1041 		if (res)
1042 			return res;
1043 	}
1044 
1045 	/* Parent and domain coherency */
1046 	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
1047 			     SAS_ADDR(dev->port->sas_addr))) {
1048 		sas_add_parent_port(dev, phy_id);
1049 		return 0;
1050 	}
1051 	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
1052 			    SAS_ADDR(dev->parent->sas_addr))) {
1053 		sas_add_parent_port(dev, phy_id);
1054 		if (ex_phy->routing_attr == TABLE_ROUTING)
1055 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
1056 		return 0;
1057 	}
1058 
1059 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
1060 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
1061 
1062 	if (ex_phy->attached_dev_type == SAS_PHY_UNUSED) {
1063 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
1064 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1065 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
1066 		}
1067 		return 0;
1068 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
1069 		return 0;
1070 
1071 	if (ex_phy->attached_dev_type != SAS_END_DEVICE &&
1072 	    ex_phy->attached_dev_type != SAS_FANOUT_EXPANDER_DEVICE &&
1073 	    ex_phy->attached_dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1074 	    ex_phy->attached_dev_type != SAS_SATA_PENDING) {
1075 		pr_warn("unknown device type(0x%x) attached to ex %016llx phy%02d\n",
1076 			ex_phy->attached_dev_type,
1077 			SAS_ADDR(dev->sas_addr),
1078 			phy_id);
1079 		return 0;
1080 	}
1081 
1082 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
1083 	if (res) {
1084 		pr_notice("configure routing for dev %016llx reported 0x%x. Forgotten\n",
1085 			  SAS_ADDR(ex_phy->attached_sas_addr), res);
1086 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
1087 		return res;
1088 	}
1089 
1090 	if (sas_ex_join_wide_port(dev, phy_id)) {
1091 		pr_debug("Attaching ex phy%02d to wide port %016llx\n",
1092 			 phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
1093 		return res;
1094 	}
1095 
1096 	switch (ex_phy->attached_dev_type) {
1097 	case SAS_END_DEVICE:
1098 	case SAS_SATA_PENDING:
1099 		child = sas_ex_discover_end_dev(dev, phy_id);
1100 		break;
1101 	case SAS_FANOUT_EXPANDER_DEVICE:
1102 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
1103 			pr_debug("second fanout expander %016llx phy%02d attached to ex %016llx phy%02d\n",
1104 				 SAS_ADDR(ex_phy->attached_sas_addr),
1105 				 ex_phy->attached_phy_id,
1106 				 SAS_ADDR(dev->sas_addr),
1107 				 phy_id);
1108 			sas_ex_disable_phy(dev, phy_id);
1109 			break;
1110 		} else
1111 			memcpy(dev->port->disc.fanout_sas_addr,
1112 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
1113 		/* fallthrough */
1114 	case SAS_EDGE_EXPANDER_DEVICE:
1115 		child = sas_ex_discover_expander(dev, phy_id);
1116 		break;
1117 	default:
1118 		break;
1119 	}
1120 
1121 	if (child) {
1122 		int i;
1123 
1124 		for (i = 0; i < ex->num_phys; i++) {
1125 			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
1126 			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
1127 				continue;
1128 			/*
1129 			 * Due to races, the phy might not get added to the
1130 			 * wide port, so we add the phy to the wide port here.
1131 			 */
1132 			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
1133 			    SAS_ADDR(child->sas_addr)) {
1134 				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
1135 				if (sas_ex_join_wide_port(dev, i))
1136 					pr_debug("Attaching ex phy%02d to wide port %016llx\n",
1137 						 i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
1138 			}
1139 		}
1140 	}
1141 
1142 	return res;
1143 }
1144 
1145 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
1146 {
1147 	struct expander_device *ex = &dev->ex_dev;
1148 	int i;
1149 
1150 	for (i = 0; i < ex->num_phys; i++) {
1151 		struct ex_phy *phy = &ex->ex_phy[i];
1152 
1153 		if (phy->phy_state == PHY_VACANT ||
1154 		    phy->phy_state == PHY_NOT_PRESENT)
1155 			continue;
1156 
1157 		if ((phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1158 		     phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE) &&
1159 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1160 
1161 			memcpy(sub_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
1162 
1163 			return 1;
1164 		}
1165 	}
1166 	return 0;
1167 }
1168 
1169 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1170 {
1171 	struct expander_device *ex = &dev->ex_dev;
1172 	struct domain_device *child;
1173 	u8 sub_addr[SAS_ADDR_SIZE] = {0, };
1174 
1175 	list_for_each_entry(child, &ex->children, siblings) {
1176 		if (child->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1177 		    child->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
1178 			continue;
1179 		if (sub_addr[0] == 0) {
1180 			sas_find_sub_addr(child, sub_addr);
1181 			continue;
1182 		} else {
1183 			u8 s2[SAS_ADDR_SIZE];
1184 
1185 			if (sas_find_sub_addr(child, s2) &&
1186 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1187 
1188 				pr_notice("ex %016llx->%016llx-?->%016llx diverges from subtractive boundary %016llx\n",
1189 					  SAS_ADDR(dev->sas_addr),
1190 					  SAS_ADDR(child->sas_addr),
1191 					  SAS_ADDR(s2),
1192 					  SAS_ADDR(sub_addr));
1193 
1194 				sas_ex_disable_port(child, s2);
1195 			}
1196 		}
1197 	}
1198 	return 0;
1199 }
1200 /**
1201  * sas_ex_discover_devices - discover devices attached to this expander
1202  * @dev: pointer to the expander domain device
1203  * @single: if you want to do a single phy, else set to -1;
1204  *
1205  * Configure this expander for use with its devices and register the
1206  * devices of this expander.
1207  */
1208 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1209 {
1210 	struct expander_device *ex = &dev->ex_dev;
1211 	int i = 0, end = ex->num_phys;
1212 	int res = 0;
1213 
1214 	if (0 <= single && single < end) {
1215 		i = single;
1216 		end = i+1;
1217 	}
1218 
1219 	for ( ; i < end; i++) {
1220 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1221 
1222 		if (ex_phy->phy_state == PHY_VACANT ||
1223 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1224 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1225 			continue;
1226 
1227 		switch (ex_phy->linkrate) {
1228 		case SAS_PHY_DISABLED:
1229 		case SAS_PHY_RESET_PROBLEM:
1230 		case SAS_SATA_PORT_SELECTOR:
1231 			continue;
1232 		default:
1233 			res = sas_ex_discover_dev(dev, i);
1234 			if (res)
1235 				break;
1236 			continue;
1237 		}
1238 	}
1239 
1240 	if (!res)
1241 		sas_check_level_subtractive_boundary(dev);
1242 
1243 	return res;
1244 }
1245 
1246 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1247 {
1248 	struct expander_device *ex = &dev->ex_dev;
1249 	int i;
1250 	u8  *sub_sas_addr = NULL;
1251 
1252 	if (dev->dev_type != SAS_EDGE_EXPANDER_DEVICE)
1253 		return 0;
1254 
1255 	for (i = 0; i < ex->num_phys; i++) {
1256 		struct ex_phy *phy = &ex->ex_phy[i];
1257 
1258 		if (phy->phy_state == PHY_VACANT ||
1259 		    phy->phy_state == PHY_NOT_PRESENT)
1260 			continue;
1261 
1262 		if ((phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE ||
1263 		     phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE) &&
1264 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1265 
1266 			if (!sub_sas_addr)
1267 				sub_sas_addr = &phy->attached_sas_addr[0];
1268 			else if (SAS_ADDR(sub_sas_addr) !=
1269 				 SAS_ADDR(phy->attached_sas_addr)) {
1270 
1271 				pr_notice("ex %016llx phy%02d diverges(%016llx) on subtractive boundary(%016llx). Disabled\n",
1272 					  SAS_ADDR(dev->sas_addr), i,
1273 					  SAS_ADDR(phy->attached_sas_addr),
1274 					  SAS_ADDR(sub_sas_addr));
1275 				sas_ex_disable_phy(dev, i);
1276 			}
1277 		}
1278 	}
1279 	return 0;
1280 }
1281 
1282 static void sas_print_parent_topology_bug(struct domain_device *child,
1283 						 struct ex_phy *parent_phy,
1284 						 struct ex_phy *child_phy)
1285 {
1286 	static const char *ex_type[] = {
1287 		[SAS_EDGE_EXPANDER_DEVICE] = "edge",
1288 		[SAS_FANOUT_EXPANDER_DEVICE] = "fanout",
1289 	};
1290 	struct domain_device *parent = child->parent;
1291 
1292 	pr_notice("%s ex %016llx phy%02d <--> %s ex %016llx phy%02d has %c:%c routing link!\n",
1293 		  ex_type[parent->dev_type],
1294 		  SAS_ADDR(parent->sas_addr),
1295 		  parent_phy->phy_id,
1296 
1297 		  ex_type[child->dev_type],
1298 		  SAS_ADDR(child->sas_addr),
1299 		  child_phy->phy_id,
1300 
1301 		  sas_route_char(parent, parent_phy),
1302 		  sas_route_char(child, child_phy));
1303 }
1304 
1305 static int sas_check_eeds(struct domain_device *child,
1306 				 struct ex_phy *parent_phy,
1307 				 struct ex_phy *child_phy)
1308 {
1309 	int res = 0;
1310 	struct domain_device *parent = child->parent;
1311 
1312 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1313 		res = -ENODEV;
1314 		pr_warn("edge ex %016llx phy S:%02d <--> edge ex %016llx phy S:%02d, while there is a fanout ex %016llx\n",
1315 			SAS_ADDR(parent->sas_addr),
1316 			parent_phy->phy_id,
1317 			SAS_ADDR(child->sas_addr),
1318 			child_phy->phy_id,
1319 			SAS_ADDR(parent->port->disc.fanout_sas_addr));
1320 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1321 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1322 		       SAS_ADDR_SIZE);
1323 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1324 		       SAS_ADDR_SIZE);
1325 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1326 		    SAS_ADDR(parent->sas_addr)) ||
1327 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1328 		    SAS_ADDR(child->sas_addr)))
1329 		   &&
1330 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1331 		     SAS_ADDR(parent->sas_addr)) ||
1332 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1333 		     SAS_ADDR(child->sas_addr))))
1334 		;
1335 	else {
1336 		res = -ENODEV;
1337 		pr_warn("edge ex %016llx phy%02d <--> edge ex %016llx phy%02d link forms a third EEDS!\n",
1338 			SAS_ADDR(parent->sas_addr),
1339 			parent_phy->phy_id,
1340 			SAS_ADDR(child->sas_addr),
1341 			child_phy->phy_id);
1342 	}
1343 
1344 	return res;
1345 }
1346 
1347 /* Here we spill over 80 columns.  It is intentional.
1348  */
1349 static int sas_check_parent_topology(struct domain_device *child)
1350 {
1351 	struct expander_device *child_ex = &child->ex_dev;
1352 	struct expander_device *parent_ex;
1353 	int i;
1354 	int res = 0;
1355 
1356 	if (!child->parent)
1357 		return 0;
1358 
1359 	if (child->parent->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1360 	    child->parent->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
1361 		return 0;
1362 
1363 	parent_ex = &child->parent->ex_dev;
1364 
1365 	for (i = 0; i < parent_ex->num_phys; i++) {
1366 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1367 		struct ex_phy *child_phy;
1368 
1369 		if (parent_phy->phy_state == PHY_VACANT ||
1370 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1371 			continue;
1372 
1373 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1374 			continue;
1375 
1376 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1377 
1378 		switch (child->parent->dev_type) {
1379 		case SAS_EDGE_EXPANDER_DEVICE:
1380 			if (child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1381 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1382 				    child_phy->routing_attr != TABLE_ROUTING) {
1383 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1384 					res = -ENODEV;
1385 				}
1386 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1387 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1388 					res = sas_check_eeds(child, parent_phy, child_phy);
1389 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1390 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1391 					res = -ENODEV;
1392 				}
1393 			} else if (parent_phy->routing_attr == TABLE_ROUTING) {
1394 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING ||
1395 				    (child_phy->routing_attr == TABLE_ROUTING &&
1396 				     child_ex->t2t_supp && parent_ex->t2t_supp)) {
1397 					/* All good */;
1398 				} else {
1399 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1400 					res = -ENODEV;
1401 				}
1402 			}
1403 			break;
1404 		case SAS_FANOUT_EXPANDER_DEVICE:
1405 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1406 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1407 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1408 				res = -ENODEV;
1409 			}
1410 			break;
1411 		default:
1412 			break;
1413 		}
1414 	}
1415 
1416 	return res;
1417 }
1418 
1419 #define RRI_REQ_SIZE  16
1420 #define RRI_RESP_SIZE 44
1421 
1422 static int sas_configure_present(struct domain_device *dev, int phy_id,
1423 				 u8 *sas_addr, int *index, int *present)
1424 {
1425 	int i, res = 0;
1426 	struct expander_device *ex = &dev->ex_dev;
1427 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1428 	u8 *rri_req;
1429 	u8 *rri_resp;
1430 
1431 	*present = 0;
1432 	*index = 0;
1433 
1434 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1435 	if (!rri_req)
1436 		return -ENOMEM;
1437 
1438 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1439 	if (!rri_resp) {
1440 		kfree(rri_req);
1441 		return -ENOMEM;
1442 	}
1443 
1444 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1445 	rri_req[9] = phy_id;
1446 
1447 	for (i = 0; i < ex->max_route_indexes ; i++) {
1448 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1449 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1450 				       RRI_RESP_SIZE);
1451 		if (res)
1452 			goto out;
1453 		res = rri_resp[2];
1454 		if (res == SMP_RESP_NO_INDEX) {
1455 			pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1456 				SAS_ADDR(dev->sas_addr), phy_id, i);
1457 			goto out;
1458 		} else if (res != SMP_RESP_FUNC_ACC) {
1459 			pr_notice("%s: dev %016llx phy%02d index 0x%x result 0x%x\n",
1460 				  __func__, SAS_ADDR(dev->sas_addr), phy_id,
1461 				  i, res);
1462 			goto out;
1463 		}
1464 		if (SAS_ADDR(sas_addr) != 0) {
1465 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1466 				*index = i;
1467 				if ((rri_resp[12] & 0x80) == 0x80)
1468 					*present = 0;
1469 				else
1470 					*present = 1;
1471 				goto out;
1472 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1473 				*index = i;
1474 				*present = 0;
1475 				goto out;
1476 			}
1477 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1478 			   phy->last_da_index < i) {
1479 			phy->last_da_index = i;
1480 			*index = i;
1481 			*present = 0;
1482 			goto out;
1483 		}
1484 	}
1485 	res = -1;
1486 out:
1487 	kfree(rri_req);
1488 	kfree(rri_resp);
1489 	return res;
1490 }
1491 
1492 #define CRI_REQ_SIZE  44
1493 #define CRI_RESP_SIZE  8
1494 
1495 static int sas_configure_set(struct domain_device *dev, int phy_id,
1496 			     u8 *sas_addr, int index, int include)
1497 {
1498 	int res;
1499 	u8 *cri_req;
1500 	u8 *cri_resp;
1501 
1502 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1503 	if (!cri_req)
1504 		return -ENOMEM;
1505 
1506 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1507 	if (!cri_resp) {
1508 		kfree(cri_req);
1509 		return -ENOMEM;
1510 	}
1511 
1512 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1513 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1514 	cri_req[9] = phy_id;
1515 	if (SAS_ADDR(sas_addr) == 0 || !include)
1516 		cri_req[12] |= 0x80;
1517 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1518 
1519 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1520 			       CRI_RESP_SIZE);
1521 	if (res)
1522 		goto out;
1523 	res = cri_resp[2];
1524 	if (res == SMP_RESP_NO_INDEX) {
1525 		pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1526 			SAS_ADDR(dev->sas_addr), phy_id, index);
1527 	}
1528 out:
1529 	kfree(cri_req);
1530 	kfree(cri_resp);
1531 	return res;
1532 }
1533 
1534 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1535 				    u8 *sas_addr, int include)
1536 {
1537 	int index;
1538 	int present;
1539 	int res;
1540 
1541 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1542 	if (res)
1543 		return res;
1544 	if (include ^ present)
1545 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1546 
1547 	return res;
1548 }
1549 
1550 /**
1551  * sas_configure_parent - configure routing table of parent
1552  * @parent: parent expander
1553  * @child: child expander
1554  * @sas_addr: SAS port identifier of device directly attached to child
1555  * @include: whether or not to include @child in the expander routing table
1556  */
1557 static int sas_configure_parent(struct domain_device *parent,
1558 				struct domain_device *child,
1559 				u8 *sas_addr, int include)
1560 {
1561 	struct expander_device *ex_parent = &parent->ex_dev;
1562 	int res = 0;
1563 	int i;
1564 
1565 	if (parent->parent) {
1566 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1567 					   include);
1568 		if (res)
1569 			return res;
1570 	}
1571 
1572 	if (ex_parent->conf_route_table == 0) {
1573 		pr_debug("ex %016llx has self-configuring routing table\n",
1574 			 SAS_ADDR(parent->sas_addr));
1575 		return 0;
1576 	}
1577 
1578 	for (i = 0; i < ex_parent->num_phys; i++) {
1579 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1580 
1581 		if ((phy->routing_attr == TABLE_ROUTING) &&
1582 		    (SAS_ADDR(phy->attached_sas_addr) ==
1583 		     SAS_ADDR(child->sas_addr))) {
1584 			res = sas_configure_phy(parent, i, sas_addr, include);
1585 			if (res)
1586 				return res;
1587 		}
1588 	}
1589 
1590 	return res;
1591 }
1592 
1593 /**
1594  * sas_configure_routing - configure routing
1595  * @dev: expander device
1596  * @sas_addr: port identifier of device directly attached to the expander device
1597  */
1598 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1599 {
1600 	if (dev->parent)
1601 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1602 	return 0;
1603 }
1604 
1605 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1606 {
1607 	if (dev->parent)
1608 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1609 	return 0;
1610 }
1611 
1612 /**
1613  * sas_discover_expander - expander discovery
1614  * @dev: pointer to expander domain device
1615  *
1616  * See comment in sas_discover_sata().
1617  */
1618 static int sas_discover_expander(struct domain_device *dev)
1619 {
1620 	int res;
1621 
1622 	res = sas_notify_lldd_dev_found(dev);
1623 	if (res)
1624 		return res;
1625 
1626 	res = sas_ex_general(dev);
1627 	if (res)
1628 		goto out_err;
1629 	res = sas_ex_manuf_info(dev);
1630 	if (res)
1631 		goto out_err;
1632 
1633 	res = sas_expander_discover(dev);
1634 	if (res) {
1635 		pr_warn("expander %016llx discovery failed(0x%x)\n",
1636 			SAS_ADDR(dev->sas_addr), res);
1637 		goto out_err;
1638 	}
1639 
1640 	sas_check_ex_subtractive_boundary(dev);
1641 	res = sas_check_parent_topology(dev);
1642 	if (res)
1643 		goto out_err;
1644 	return 0;
1645 out_err:
1646 	sas_notify_lldd_dev_gone(dev);
1647 	return res;
1648 }
1649 
1650 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1651 {
1652 	int res = 0;
1653 	struct domain_device *dev;
1654 
1655 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1656 		if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1657 		    dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1658 			struct sas_expander_device *ex =
1659 				rphy_to_expander_device(dev->rphy);
1660 
1661 			if (level == ex->level)
1662 				res = sas_ex_discover_devices(dev, -1);
1663 			else if (level > 0)
1664 				res = sas_ex_discover_devices(port->port_dev, -1);
1665 
1666 		}
1667 	}
1668 
1669 	return res;
1670 }
1671 
1672 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1673 {
1674 	int res;
1675 	int level;
1676 
1677 	do {
1678 		level = port->disc.max_level;
1679 		res = sas_ex_level_discovery(port, level);
1680 		mb();
1681 	} while (level < port->disc.max_level);
1682 
1683 	return res;
1684 }
1685 
1686 int sas_discover_root_expander(struct domain_device *dev)
1687 {
1688 	int res;
1689 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1690 
1691 	res = sas_rphy_add(dev->rphy);
1692 	if (res)
1693 		goto out_err;
1694 
1695 	ex->level = dev->port->disc.max_level; /* 0 */
1696 	res = sas_discover_expander(dev);
1697 	if (res)
1698 		goto out_err2;
1699 
1700 	sas_ex_bfs_disc(dev->port);
1701 
1702 	return res;
1703 
1704 out_err2:
1705 	sas_rphy_remove(dev->rphy);
1706 out_err:
1707 	return res;
1708 }
1709 
1710 /* ---------- Domain revalidation ---------- */
1711 
1712 static int sas_get_phy_discover(struct domain_device *dev,
1713 				int phy_id, struct smp_resp *disc_resp)
1714 {
1715 	int res;
1716 	u8 *disc_req;
1717 
1718 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1719 	if (!disc_req)
1720 		return -ENOMEM;
1721 
1722 	disc_req[1] = SMP_DISCOVER;
1723 	disc_req[9] = phy_id;
1724 
1725 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1726 			       disc_resp, DISCOVER_RESP_SIZE);
1727 	if (res)
1728 		goto out;
1729 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1730 		res = disc_resp->result;
1731 		goto out;
1732 	}
1733 out:
1734 	kfree(disc_req);
1735 	return res;
1736 }
1737 
1738 static int sas_get_phy_change_count(struct domain_device *dev,
1739 				    int phy_id, int *pcc)
1740 {
1741 	int res;
1742 	struct smp_resp *disc_resp;
1743 
1744 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1745 	if (!disc_resp)
1746 		return -ENOMEM;
1747 
1748 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1749 	if (!res)
1750 		*pcc = disc_resp->disc.change_count;
1751 
1752 	kfree(disc_resp);
1753 	return res;
1754 }
1755 
1756 static int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
1757 				    u8 *sas_addr, enum sas_device_type *type)
1758 {
1759 	int res;
1760 	struct smp_resp *disc_resp;
1761 	struct discover_resp *dr;
1762 
1763 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1764 	if (!disc_resp)
1765 		return -ENOMEM;
1766 	dr = &disc_resp->disc;
1767 
1768 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1769 	if (res == 0) {
1770 		memcpy(sas_addr, disc_resp->disc.attached_sas_addr,
1771 		       SAS_ADDR_SIZE);
1772 		*type = to_dev_type(dr);
1773 		if (*type == 0)
1774 			memset(sas_addr, 0, SAS_ADDR_SIZE);
1775 	}
1776 	kfree(disc_resp);
1777 	return res;
1778 }
1779 
1780 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1781 			      int from_phy, bool update)
1782 {
1783 	struct expander_device *ex = &dev->ex_dev;
1784 	int res = 0;
1785 	int i;
1786 
1787 	for (i = from_phy; i < ex->num_phys; i++) {
1788 		int phy_change_count = 0;
1789 
1790 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1791 		switch (res) {
1792 		case SMP_RESP_PHY_VACANT:
1793 		case SMP_RESP_NO_PHY:
1794 			continue;
1795 		case SMP_RESP_FUNC_ACC:
1796 			break;
1797 		default:
1798 			return res;
1799 		}
1800 
1801 		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1802 			if (update)
1803 				ex->ex_phy[i].phy_change_count =
1804 					phy_change_count;
1805 			*phy_id = i;
1806 			return 0;
1807 		}
1808 	}
1809 	return 0;
1810 }
1811 
1812 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1813 {
1814 	int res;
1815 	u8  *rg_req;
1816 	struct smp_resp  *rg_resp;
1817 
1818 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1819 	if (!rg_req)
1820 		return -ENOMEM;
1821 
1822 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1823 	if (!rg_resp) {
1824 		kfree(rg_req);
1825 		return -ENOMEM;
1826 	}
1827 
1828 	rg_req[1] = SMP_REPORT_GENERAL;
1829 
1830 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1831 			       RG_RESP_SIZE);
1832 	if (res)
1833 		goto out;
1834 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1835 		res = rg_resp->result;
1836 		goto out;
1837 	}
1838 
1839 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1840 out:
1841 	kfree(rg_resp);
1842 	kfree(rg_req);
1843 	return res;
1844 }
1845 /**
1846  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1847  * @dev:domain device to be detect.
1848  * @src_dev: the device which originated BROADCAST(CHANGE).
1849  *
1850  * Add self-configuration expander support. Suppose two expander cascading,
1851  * when the first level expander is self-configuring, hotplug the disks in
1852  * second level expander, BROADCAST(CHANGE) will not only be originated
1853  * in the second level expander, but also be originated in the first level
1854  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1855  * expander changed count in two level expanders will all increment at least
1856  * once, but the phy which chang count has changed is the source device which
1857  * we concerned.
1858  */
1859 
1860 static int sas_find_bcast_dev(struct domain_device *dev,
1861 			      struct domain_device **src_dev)
1862 {
1863 	struct expander_device *ex = &dev->ex_dev;
1864 	int ex_change_count = -1;
1865 	int phy_id = -1;
1866 	int res;
1867 	struct domain_device *ch;
1868 
1869 	res = sas_get_ex_change_count(dev, &ex_change_count);
1870 	if (res)
1871 		goto out;
1872 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1873 		/* Just detect if this expander phys phy change count changed,
1874 		* in order to determine if this expander originate BROADCAST,
1875 		* and do not update phy change count field in our structure.
1876 		*/
1877 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1878 		if (phy_id != -1) {
1879 			*src_dev = dev;
1880 			ex->ex_change_count = ex_change_count;
1881 			pr_info("ex %016llx phy%02d change count has changed\n",
1882 				SAS_ADDR(dev->sas_addr), phy_id);
1883 			return res;
1884 		} else
1885 			pr_info("ex %016llx phys DID NOT change\n",
1886 				SAS_ADDR(dev->sas_addr));
1887 	}
1888 	list_for_each_entry(ch, &ex->children, siblings) {
1889 		if (ch->dev_type == SAS_EDGE_EXPANDER_DEVICE || ch->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1890 			res = sas_find_bcast_dev(ch, src_dev);
1891 			if (*src_dev)
1892 				return res;
1893 		}
1894 	}
1895 out:
1896 	return res;
1897 }
1898 
1899 static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
1900 {
1901 	struct expander_device *ex = &dev->ex_dev;
1902 	struct domain_device *child, *n;
1903 
1904 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1905 		set_bit(SAS_DEV_GONE, &child->state);
1906 		if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1907 		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
1908 			sas_unregister_ex_tree(port, child);
1909 		else
1910 			sas_unregister_dev(port, child);
1911 	}
1912 	sas_unregister_dev(port, dev);
1913 }
1914 
1915 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1916 					 int phy_id, bool last)
1917 {
1918 	struct expander_device *ex_dev = &parent->ex_dev;
1919 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1920 	struct domain_device *child, *n, *found = NULL;
1921 	if (last) {
1922 		list_for_each_entry_safe(child, n,
1923 			&ex_dev->children, siblings) {
1924 			if (SAS_ADDR(child->sas_addr) ==
1925 			    SAS_ADDR(phy->attached_sas_addr)) {
1926 				set_bit(SAS_DEV_GONE, &child->state);
1927 				if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1928 				    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
1929 					sas_unregister_ex_tree(parent->port, child);
1930 				else
1931 					sas_unregister_dev(parent->port, child);
1932 				found = child;
1933 				break;
1934 			}
1935 		}
1936 		sas_disable_routing(parent, phy->attached_sas_addr);
1937 	}
1938 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1939 	if (phy->port) {
1940 		sas_port_delete_phy(phy->port, phy->phy);
1941 		sas_device_set_phy(found, phy->port);
1942 		if (phy->port->num_phys == 0)
1943 			list_add_tail(&phy->port->del_list,
1944 				&parent->port->sas_port_del_list);
1945 		phy->port = NULL;
1946 	}
1947 }
1948 
1949 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1950 					  const int level)
1951 {
1952 	struct expander_device *ex_root = &root->ex_dev;
1953 	struct domain_device *child;
1954 	int res = 0;
1955 
1956 	list_for_each_entry(child, &ex_root->children, siblings) {
1957 		if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1958 		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1959 			struct sas_expander_device *ex =
1960 				rphy_to_expander_device(child->rphy);
1961 
1962 			if (level > ex->level)
1963 				res = sas_discover_bfs_by_root_level(child,
1964 								     level);
1965 			else if (level == ex->level)
1966 				res = sas_ex_discover_devices(child, -1);
1967 		}
1968 	}
1969 	return res;
1970 }
1971 
1972 static int sas_discover_bfs_by_root(struct domain_device *dev)
1973 {
1974 	int res;
1975 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1976 	int level = ex->level+1;
1977 
1978 	res = sas_ex_discover_devices(dev, -1);
1979 	if (res)
1980 		goto out;
1981 	do {
1982 		res = sas_discover_bfs_by_root_level(dev, level);
1983 		mb();
1984 		level += 1;
1985 	} while (level <= dev->port->disc.max_level);
1986 out:
1987 	return res;
1988 }
1989 
1990 static int sas_discover_new(struct domain_device *dev, int phy_id)
1991 {
1992 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1993 	struct domain_device *child;
1994 	int res;
1995 
1996 	pr_debug("ex %016llx phy%02d new device attached\n",
1997 		 SAS_ADDR(dev->sas_addr), phy_id);
1998 	res = sas_ex_phy_discover(dev, phy_id);
1999 	if (res)
2000 		return res;
2001 
2002 	if (sas_ex_join_wide_port(dev, phy_id))
2003 		return 0;
2004 
2005 	res = sas_ex_discover_devices(dev, phy_id);
2006 	if (res)
2007 		return res;
2008 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
2009 		if (SAS_ADDR(child->sas_addr) ==
2010 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
2011 			if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
2012 			    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
2013 				res = sas_discover_bfs_by_root(child);
2014 			break;
2015 		}
2016 	}
2017 	return res;
2018 }
2019 
2020 static bool dev_type_flutter(enum sas_device_type new, enum sas_device_type old)
2021 {
2022 	if (old == new)
2023 		return true;
2024 
2025 	/* treat device directed resets as flutter, if we went
2026 	 * SAS_END_DEVICE to SAS_SATA_PENDING the link needs recovery
2027 	 */
2028 	if ((old == SAS_SATA_PENDING && new == SAS_END_DEVICE) ||
2029 	    (old == SAS_END_DEVICE && new == SAS_SATA_PENDING))
2030 		return true;
2031 
2032 	return false;
2033 }
2034 
2035 static int sas_rediscover_dev(struct domain_device *dev, int phy_id,
2036 			      bool last, int sibling)
2037 {
2038 	struct expander_device *ex = &dev->ex_dev;
2039 	struct ex_phy *phy = &ex->ex_phy[phy_id];
2040 	enum sas_device_type type = SAS_PHY_UNUSED;
2041 	u8 sas_addr[SAS_ADDR_SIZE];
2042 	char msg[80] = "";
2043 	int res;
2044 
2045 	if (!last)
2046 		sprintf(msg, ", part of a wide port with phy%02d", sibling);
2047 
2048 	pr_debug("ex %016llx rediscovering phy%02d%s\n",
2049 		 SAS_ADDR(dev->sas_addr), phy_id, msg);
2050 
2051 	memset(sas_addr, 0, SAS_ADDR_SIZE);
2052 	res = sas_get_phy_attached_dev(dev, phy_id, sas_addr, &type);
2053 	switch (res) {
2054 	case SMP_RESP_NO_PHY:
2055 		phy->phy_state = PHY_NOT_PRESENT;
2056 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2057 		return res;
2058 	case SMP_RESP_PHY_VACANT:
2059 		phy->phy_state = PHY_VACANT;
2060 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2061 		return res;
2062 	case SMP_RESP_FUNC_ACC:
2063 		break;
2064 	case -ECOMM:
2065 		break;
2066 	default:
2067 		return res;
2068 	}
2069 
2070 	if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM)) {
2071 		phy->phy_state = PHY_EMPTY;
2072 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2073 		/*
2074 		 * Even though the PHY is empty, for convenience we discover
2075 		 * the PHY to update the PHY info, like negotiated linkrate.
2076 		 */
2077 		sas_ex_phy_discover(dev, phy_id);
2078 		return res;
2079 	} else if (SAS_ADDR(sas_addr) == SAS_ADDR(phy->attached_sas_addr) &&
2080 		   dev_type_flutter(type, phy->attached_dev_type)) {
2081 		struct domain_device *ata_dev = sas_ex_to_ata(dev, phy_id);
2082 		char *action = "";
2083 
2084 		sas_ex_phy_discover(dev, phy_id);
2085 
2086 		if (ata_dev && phy->attached_dev_type == SAS_SATA_PENDING)
2087 			action = ", needs recovery";
2088 		pr_debug("ex %016llx phy%02d broadcast flutter%s\n",
2089 			 SAS_ADDR(dev->sas_addr), phy_id, action);
2090 		return res;
2091 	}
2092 
2093 	/* we always have to delete the old device when we went here */
2094 	pr_info("ex %016llx phy%02d replace %016llx\n",
2095 		SAS_ADDR(dev->sas_addr), phy_id,
2096 		SAS_ADDR(phy->attached_sas_addr));
2097 	sas_unregister_devs_sas_addr(dev, phy_id, last);
2098 
2099 	return sas_discover_new(dev, phy_id);
2100 }
2101 
2102 /**
2103  * sas_rediscover - revalidate the domain.
2104  * @dev:domain device to be detect.
2105  * @phy_id: the phy id will be detected.
2106  *
2107  * NOTE: this process _must_ quit (return) as soon as any connection
2108  * errors are encountered.  Connection recovery is done elsewhere.
2109  * Discover process only interrogates devices in order to discover the
2110  * domain.For plugging out, we un-register the device only when it is
2111  * the last phy in the port, for other phys in this port, we just delete it
2112  * from the port.For inserting, we do discovery when it is the
2113  * first phy,for other phys in this port, we add it to the port to
2114  * forming the wide-port.
2115  */
2116 static int sas_rediscover(struct domain_device *dev, const int phy_id)
2117 {
2118 	struct expander_device *ex = &dev->ex_dev;
2119 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
2120 	int res = 0;
2121 	int i;
2122 	bool last = true;	/* is this the last phy of the port */
2123 
2124 	pr_debug("ex %016llx phy%02d originated BROADCAST(CHANGE)\n",
2125 		 SAS_ADDR(dev->sas_addr), phy_id);
2126 
2127 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
2128 		for (i = 0; i < ex->num_phys; i++) {
2129 			struct ex_phy *phy = &ex->ex_phy[i];
2130 
2131 			if (i == phy_id)
2132 				continue;
2133 			if (SAS_ADDR(phy->attached_sas_addr) ==
2134 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
2135 				last = false;
2136 				break;
2137 			}
2138 		}
2139 		res = sas_rediscover_dev(dev, phy_id, last, i);
2140 	} else
2141 		res = sas_discover_new(dev, phy_id);
2142 	return res;
2143 }
2144 
2145 /**
2146  * sas_ex_revalidate_domain - revalidate the domain
2147  * @port_dev: port domain device.
2148  *
2149  * NOTE: this process _must_ quit (return) as soon as any connection
2150  * errors are encountered.  Connection recovery is done elsewhere.
2151  * Discover process only interrogates devices in order to discover the
2152  * domain.
2153  */
2154 int sas_ex_revalidate_domain(struct domain_device *port_dev)
2155 {
2156 	int res;
2157 	struct domain_device *dev = NULL;
2158 
2159 	res = sas_find_bcast_dev(port_dev, &dev);
2160 	if (res == 0 && dev) {
2161 		struct expander_device *ex = &dev->ex_dev;
2162 		int i = 0, phy_id;
2163 
2164 		do {
2165 			phy_id = -1;
2166 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
2167 			if (phy_id == -1)
2168 				break;
2169 			res = sas_rediscover(dev, phy_id);
2170 			i = phy_id + 1;
2171 		} while (i < ex->num_phys);
2172 	}
2173 	return res;
2174 }
2175 
2176 void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
2177 		struct sas_rphy *rphy)
2178 {
2179 	struct domain_device *dev;
2180 	unsigned int rcvlen = 0;
2181 	int ret = -EINVAL;
2182 
2183 	/* no rphy means no smp target support (ie aic94xx host) */
2184 	if (!rphy)
2185 		return sas_smp_host_handler(job, shost);
2186 
2187 	switch (rphy->identify.device_type) {
2188 	case SAS_EDGE_EXPANDER_DEVICE:
2189 	case SAS_FANOUT_EXPANDER_DEVICE:
2190 		break;
2191 	default:
2192 		pr_err("%s: can we send a smp request to a device?\n",
2193 		       __func__);
2194 		goto out;
2195 	}
2196 
2197 	dev = sas_find_dev_by_rphy(rphy);
2198 	if (!dev) {
2199 		pr_err("%s: fail to find a domain_device?\n", __func__);
2200 		goto out;
2201 	}
2202 
2203 	/* do we need to support multiple segments? */
2204 	if (job->request_payload.sg_cnt > 1 ||
2205 	    job->reply_payload.sg_cnt > 1) {
2206 		pr_info("%s: multiple segments req %u, rsp %u\n",
2207 			__func__, job->request_payload.payload_len,
2208 			job->reply_payload.payload_len);
2209 		goto out;
2210 	}
2211 
2212 	ret = smp_execute_task_sg(dev, job->request_payload.sg_list,
2213 			job->reply_payload.sg_list);
2214 	if (ret >= 0) {
2215 		/* bsg_job_done() requires the length received  */
2216 		rcvlen = job->reply_payload.payload_len - ret;
2217 		ret = 0;
2218 	}
2219 
2220 out:
2221 	bsg_job_done(job, ret, rcvlen);
2222 }
2223