1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Serial Attached SCSI (SAS) Expander discovery and configuration
4  *
5  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
6  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
7  *
8  * This file is licensed under GPLv2.
9  */
10 
11 #include <linux/scatterlist.h>
12 #include <linux/blkdev.h>
13 #include <linux/slab.h>
14 #include <asm/unaligned.h>
15 
16 #include "sas_internal.h"
17 
18 #include <scsi/sas_ata.h>
19 #include <scsi/scsi_transport.h>
20 #include <scsi/scsi_transport_sas.h>
21 #include "scsi_sas_internal.h"
22 
23 static int sas_discover_expander(struct domain_device *dev);
24 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
25 static int sas_configure_phy(struct domain_device *dev, int phy_id,
26 			     u8 *sas_addr, int include);
27 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
28 
29 /* ---------- SMP task management ---------- */
30 
31 /* Give it some long enough timeout. In seconds. */
32 #define SMP_TIMEOUT 10
33 
34 static int smp_execute_task_sg(struct domain_device *dev,
35 		struct scatterlist *req, struct scatterlist *resp)
36 {
37 	int res, retry;
38 	struct sas_task *task = NULL;
39 	struct sas_internal *i =
40 		to_sas_internal(dev->port->ha->core.shost->transportt);
41 	struct sas_ha_struct *ha = dev->port->ha;
42 
43 	pm_runtime_get_sync(ha->dev);
44 	mutex_lock(&dev->ex_dev.cmd_mutex);
45 	for (retry = 0; retry < 3; retry++) {
46 		if (test_bit(SAS_DEV_GONE, &dev->state)) {
47 			res = -ECOMM;
48 			break;
49 		}
50 
51 		task = sas_alloc_slow_task(GFP_KERNEL);
52 		if (!task) {
53 			res = -ENOMEM;
54 			break;
55 		}
56 		task->dev = dev;
57 		task->task_proto = dev->tproto;
58 		task->smp_task.smp_req = *req;
59 		task->smp_task.smp_resp = *resp;
60 
61 		task->task_done = sas_task_internal_done;
62 
63 		task->slow_task->timer.function = sas_task_internal_timedout;
64 		task->slow_task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
65 		add_timer(&task->slow_task->timer);
66 
67 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
68 
69 		if (res) {
70 			del_timer_sync(&task->slow_task->timer);
71 			pr_notice("executing SMP task failed:%d\n", res);
72 			break;
73 		}
74 
75 		wait_for_completion(&task->slow_task->completion);
76 		res = -ECOMM;
77 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
78 			pr_notice("smp task timed out or aborted\n");
79 			i->dft->lldd_abort_task(task);
80 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
81 				pr_notice("SMP task aborted and not done\n");
82 				break;
83 			}
84 		}
85 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
86 		    task->task_status.stat == SAS_SAM_STAT_GOOD) {
87 			res = 0;
88 			break;
89 		}
90 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
91 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
92 			/* no error, but return the number of bytes of
93 			 * underrun */
94 			res = task->task_status.residual;
95 			break;
96 		}
97 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
98 		    task->task_status.stat == SAS_DATA_OVERRUN) {
99 			res = -EMSGSIZE;
100 			break;
101 		}
102 		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
103 		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
104 			break;
105 		else {
106 			pr_notice("%s: task to dev %016llx response: 0x%x status 0x%x\n",
107 				  __func__,
108 				  SAS_ADDR(dev->sas_addr),
109 				  task->task_status.resp,
110 				  task->task_status.stat);
111 			sas_free_task(task);
112 			task = NULL;
113 		}
114 	}
115 	mutex_unlock(&dev->ex_dev.cmd_mutex);
116 	pm_runtime_put_sync(ha->dev);
117 
118 	BUG_ON(retry == 3 && task != NULL);
119 	sas_free_task(task);
120 	return res;
121 }
122 
123 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
124 			    void *resp, int resp_size)
125 {
126 	struct scatterlist req_sg;
127 	struct scatterlist resp_sg;
128 
129 	sg_init_one(&req_sg, req, req_size);
130 	sg_init_one(&resp_sg, resp, resp_size);
131 	return smp_execute_task_sg(dev, &req_sg, &resp_sg);
132 }
133 
134 /* ---------- Allocations ---------- */
135 
136 static inline void *alloc_smp_req(int size)
137 {
138 	u8 *p = kzalloc(size, GFP_KERNEL);
139 	if (p)
140 		p[0] = SMP_REQUEST;
141 	return p;
142 }
143 
144 static inline void *alloc_smp_resp(int size)
145 {
146 	return kzalloc(size, GFP_KERNEL);
147 }
148 
149 static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
150 {
151 	switch (phy->routing_attr) {
152 	case TABLE_ROUTING:
153 		if (dev->ex_dev.t2t_supp)
154 			return 'U';
155 		else
156 			return 'T';
157 	case DIRECT_ROUTING:
158 		return 'D';
159 	case SUBTRACTIVE_ROUTING:
160 		return 'S';
161 	default:
162 		return '?';
163 	}
164 }
165 
166 static enum sas_device_type to_dev_type(struct discover_resp *dr)
167 {
168 	/* This is detecting a failure to transmit initial dev to host
169 	 * FIS as described in section J.5 of sas-2 r16
170 	 */
171 	if (dr->attached_dev_type == SAS_PHY_UNUSED && dr->attached_sata_dev &&
172 	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
173 		return SAS_SATA_PENDING;
174 	else
175 		return dr->attached_dev_type;
176 }
177 
178 static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
179 			   struct smp_disc_resp *disc_resp)
180 {
181 	enum sas_device_type dev_type;
182 	enum sas_linkrate linkrate;
183 	u8 sas_addr[SAS_ADDR_SIZE];
184 	struct discover_resp *dr = &disc_resp->disc;
185 	struct sas_ha_struct *ha = dev->port->ha;
186 	struct expander_device *ex = &dev->ex_dev;
187 	struct ex_phy *phy = &ex->ex_phy[phy_id];
188 	struct sas_rphy *rphy = dev->rphy;
189 	bool new_phy = !phy->phy;
190 	char *type;
191 
192 	if (new_phy) {
193 		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
194 			return;
195 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
196 
197 		/* FIXME: error_handling */
198 		BUG_ON(!phy->phy);
199 	}
200 
201 	switch (disc_resp->result) {
202 	case SMP_RESP_PHY_VACANT:
203 		phy->phy_state = PHY_VACANT;
204 		break;
205 	default:
206 		phy->phy_state = PHY_NOT_PRESENT;
207 		break;
208 	case SMP_RESP_FUNC_ACC:
209 		phy->phy_state = PHY_EMPTY; /* do not know yet */
210 		break;
211 	}
212 
213 	/* check if anything important changed to squelch debug */
214 	dev_type = phy->attached_dev_type;
215 	linkrate  = phy->linkrate;
216 	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
217 
218 	/* Handle vacant phy - rest of dr data is not valid so skip it */
219 	if (phy->phy_state == PHY_VACANT) {
220 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
221 		phy->attached_dev_type = SAS_PHY_UNUSED;
222 		if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
223 			phy->phy_id = phy_id;
224 			goto skip;
225 		} else
226 			goto out;
227 	}
228 
229 	phy->attached_dev_type = to_dev_type(dr);
230 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
231 		goto out;
232 	phy->phy_id = phy_id;
233 	phy->linkrate = dr->linkrate;
234 	phy->attached_sata_host = dr->attached_sata_host;
235 	phy->attached_sata_dev  = dr->attached_sata_dev;
236 	phy->attached_sata_ps   = dr->attached_sata_ps;
237 	phy->attached_iproto = dr->iproto << 1;
238 	phy->attached_tproto = dr->tproto << 1;
239 	/* help some expanders that fail to zero sas_address in the 'no
240 	 * device' case
241 	 */
242 	if (phy->attached_dev_type == SAS_PHY_UNUSED ||
243 	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
244 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
245 	else
246 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
247 	phy->attached_phy_id = dr->attached_phy_id;
248 	phy->phy_change_count = dr->change_count;
249 	phy->routing_attr = dr->routing_attr;
250 	phy->virtual = dr->virtual;
251 	phy->last_da_index = -1;
252 
253 	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
254 	phy->phy->identify.device_type = dr->attached_dev_type;
255 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
256 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
257 	if (!phy->attached_tproto && dr->attached_sata_dev)
258 		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
259 	phy->phy->identify.phy_identifier = phy_id;
260 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
261 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
262 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
263 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
264 	phy->phy->negotiated_linkrate = phy->linkrate;
265 	phy->phy->enabled = (phy->linkrate != SAS_PHY_DISABLED);
266 
267  skip:
268 	if (new_phy)
269 		if (sas_phy_add(phy->phy)) {
270 			sas_phy_free(phy->phy);
271 			return;
272 		}
273 
274  out:
275 	switch (phy->attached_dev_type) {
276 	case SAS_SATA_PENDING:
277 		type = "stp pending";
278 		break;
279 	case SAS_PHY_UNUSED:
280 		type = "no device";
281 		break;
282 	case SAS_END_DEVICE:
283 		if (phy->attached_iproto) {
284 			if (phy->attached_tproto)
285 				type = "host+target";
286 			else
287 				type = "host";
288 		} else {
289 			if (dr->attached_sata_dev)
290 				type = "stp";
291 			else
292 				type = "ssp";
293 		}
294 		break;
295 	case SAS_EDGE_EXPANDER_DEVICE:
296 	case SAS_FANOUT_EXPANDER_DEVICE:
297 		type = "smp";
298 		break;
299 	default:
300 		type = "unknown";
301 	}
302 
303 	/* this routine is polled by libata error recovery so filter
304 	 * unimportant messages
305 	 */
306 	if (new_phy || phy->attached_dev_type != dev_type ||
307 	    phy->linkrate != linkrate ||
308 	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
309 		/* pass */;
310 	else
311 		return;
312 
313 	/* if the attached device type changed and ata_eh is active,
314 	 * make sure we run revalidation when eh completes (see:
315 	 * sas_enable_revalidation)
316 	 */
317 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
318 		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
319 
320 	pr_debug("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
321 		 test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
322 		 SAS_ADDR(dev->sas_addr), phy->phy_id,
323 		 sas_route_char(dev, phy), phy->linkrate,
324 		 SAS_ADDR(phy->attached_sas_addr), type);
325 }
326 
327 /* check if we have an existing attached ata device on this expander phy */
328 struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
329 {
330 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
331 	struct domain_device *dev;
332 	struct sas_rphy *rphy;
333 
334 	if (!ex_phy->port)
335 		return NULL;
336 
337 	rphy = ex_phy->port->rphy;
338 	if (!rphy)
339 		return NULL;
340 
341 	dev = sas_find_dev_by_rphy(rphy);
342 
343 	if (dev && dev_is_sata(dev))
344 		return dev;
345 
346 	return NULL;
347 }
348 
349 #define DISCOVER_REQ_SIZE  16
350 #define DISCOVER_RESP_SIZE sizeof(struct smp_disc_resp)
351 
352 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
353 				      struct smp_disc_resp *disc_resp,
354 				      int single)
355 {
356 	struct discover_resp *dr = &disc_resp->disc;
357 	int res;
358 
359 	disc_req[9] = single;
360 
361 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
362 			       disc_resp, DISCOVER_RESP_SIZE);
363 	if (res)
364 		return res;
365 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
366 		pr_notice("Found loopback topology, just ignore it!\n");
367 		return 0;
368 	}
369 	sas_set_ex_phy(dev, single, disc_resp);
370 	return 0;
371 }
372 
373 int sas_ex_phy_discover(struct domain_device *dev, int single)
374 {
375 	struct expander_device *ex = &dev->ex_dev;
376 	int  res = 0;
377 	u8   *disc_req;
378 	struct smp_disc_resp *disc_resp;
379 
380 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
381 	if (!disc_req)
382 		return -ENOMEM;
383 
384 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
385 	if (!disc_resp) {
386 		kfree(disc_req);
387 		return -ENOMEM;
388 	}
389 
390 	disc_req[1] = SMP_DISCOVER;
391 
392 	if (0 <= single && single < ex->num_phys) {
393 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
394 	} else {
395 		int i;
396 
397 		for (i = 0; i < ex->num_phys; i++) {
398 			res = sas_ex_phy_discover_helper(dev, disc_req,
399 							 disc_resp, i);
400 			if (res)
401 				goto out_err;
402 		}
403 	}
404 out_err:
405 	kfree(disc_resp);
406 	kfree(disc_req);
407 	return res;
408 }
409 
410 static int sas_expander_discover(struct domain_device *dev)
411 {
412 	struct expander_device *ex = &dev->ex_dev;
413 	int res;
414 
415 	ex->ex_phy = kcalloc(ex->num_phys, sizeof(*ex->ex_phy), GFP_KERNEL);
416 	if (!ex->ex_phy)
417 		return -ENOMEM;
418 
419 	res = sas_ex_phy_discover(dev, -1);
420 	if (res)
421 		goto out_err;
422 
423 	return 0;
424  out_err:
425 	kfree(ex->ex_phy);
426 	ex->ex_phy = NULL;
427 	return res;
428 }
429 
430 #define MAX_EXPANDER_PHYS 128
431 
432 #define RG_REQ_SIZE   8
433 #define RG_RESP_SIZE  sizeof(struct smp_rg_resp)
434 
435 static int sas_ex_general(struct domain_device *dev)
436 {
437 	u8 *rg_req;
438 	struct smp_rg_resp *rg_resp;
439 	struct report_general_resp *rg;
440 	int res;
441 	int i;
442 
443 	rg_req = alloc_smp_req(RG_REQ_SIZE);
444 	if (!rg_req)
445 		return -ENOMEM;
446 
447 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
448 	if (!rg_resp) {
449 		kfree(rg_req);
450 		return -ENOMEM;
451 	}
452 
453 	rg_req[1] = SMP_REPORT_GENERAL;
454 
455 	for (i = 0; i < 5; i++) {
456 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
457 				       RG_RESP_SIZE);
458 
459 		if (res) {
460 			pr_notice("RG to ex %016llx failed:0x%x\n",
461 				  SAS_ADDR(dev->sas_addr), res);
462 			goto out;
463 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
464 			pr_debug("RG:ex %016llx returned SMP result:0x%x\n",
465 				 SAS_ADDR(dev->sas_addr), rg_resp->result);
466 			res = rg_resp->result;
467 			goto out;
468 		}
469 
470 		rg = &rg_resp->rg;
471 		dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
472 		dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
473 		dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
474 		dev->ex_dev.t2t_supp = rg->t2t_supp;
475 		dev->ex_dev.conf_route_table = rg->conf_route_table;
476 		dev->ex_dev.configuring = rg->configuring;
477 		memcpy(dev->ex_dev.enclosure_logical_id,
478 		       rg->enclosure_logical_id, 8);
479 
480 		if (dev->ex_dev.configuring) {
481 			pr_debug("RG: ex %016llx self-configuring...\n",
482 				 SAS_ADDR(dev->sas_addr));
483 			schedule_timeout_interruptible(5*HZ);
484 		} else
485 			break;
486 	}
487 out:
488 	kfree(rg_req);
489 	kfree(rg_resp);
490 	return res;
491 }
492 
493 static void ex_assign_manuf_info(struct domain_device *dev, void
494 					*_mi_resp)
495 {
496 	u8 *mi_resp = _mi_resp;
497 	struct sas_rphy *rphy = dev->rphy;
498 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
499 
500 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
501 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
502 	memcpy(edev->product_rev, mi_resp + 36,
503 	       SAS_EXPANDER_PRODUCT_REV_LEN);
504 
505 	if (mi_resp[8] & 1) {
506 		memcpy(edev->component_vendor_id, mi_resp + 40,
507 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
508 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
509 		edev->component_revision_id = mi_resp[50];
510 	}
511 }
512 
513 #define MI_REQ_SIZE   8
514 #define MI_RESP_SIZE 64
515 
516 static int sas_ex_manuf_info(struct domain_device *dev)
517 {
518 	u8 *mi_req;
519 	u8 *mi_resp;
520 	int res;
521 
522 	mi_req = alloc_smp_req(MI_REQ_SIZE);
523 	if (!mi_req)
524 		return -ENOMEM;
525 
526 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
527 	if (!mi_resp) {
528 		kfree(mi_req);
529 		return -ENOMEM;
530 	}
531 
532 	mi_req[1] = SMP_REPORT_MANUF_INFO;
533 
534 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp, MI_RESP_SIZE);
535 	if (res) {
536 		pr_notice("MI: ex %016llx failed:0x%x\n",
537 			  SAS_ADDR(dev->sas_addr), res);
538 		goto out;
539 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
540 		pr_debug("MI ex %016llx returned SMP result:0x%x\n",
541 			 SAS_ADDR(dev->sas_addr), mi_resp[2]);
542 		goto out;
543 	}
544 
545 	ex_assign_manuf_info(dev, mi_resp);
546 out:
547 	kfree(mi_req);
548 	kfree(mi_resp);
549 	return res;
550 }
551 
552 #define PC_REQ_SIZE  44
553 #define PC_RESP_SIZE 8
554 
555 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
556 			enum phy_func phy_func,
557 			struct sas_phy_linkrates *rates)
558 {
559 	u8 *pc_req;
560 	u8 *pc_resp;
561 	int res;
562 
563 	pc_req = alloc_smp_req(PC_REQ_SIZE);
564 	if (!pc_req)
565 		return -ENOMEM;
566 
567 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
568 	if (!pc_resp) {
569 		kfree(pc_req);
570 		return -ENOMEM;
571 	}
572 
573 	pc_req[1] = SMP_PHY_CONTROL;
574 	pc_req[9] = phy_id;
575 	pc_req[10] = phy_func;
576 	if (rates) {
577 		pc_req[32] = rates->minimum_linkrate << 4;
578 		pc_req[33] = rates->maximum_linkrate << 4;
579 	}
580 
581 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp, PC_RESP_SIZE);
582 	if (res) {
583 		pr_err("ex %016llx phy%02d PHY control failed: %d\n",
584 		       SAS_ADDR(dev->sas_addr), phy_id, res);
585 	} else if (pc_resp[2] != SMP_RESP_FUNC_ACC) {
586 		pr_err("ex %016llx phy%02d PHY control failed: function result 0x%x\n",
587 		       SAS_ADDR(dev->sas_addr), phy_id, pc_resp[2]);
588 		res = pc_resp[2];
589 	}
590 	kfree(pc_resp);
591 	kfree(pc_req);
592 	return res;
593 }
594 
595 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
596 {
597 	struct expander_device *ex = &dev->ex_dev;
598 	struct ex_phy *phy = &ex->ex_phy[phy_id];
599 
600 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
601 	phy->linkrate = SAS_PHY_DISABLED;
602 }
603 
604 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
605 {
606 	struct expander_device *ex = &dev->ex_dev;
607 	int i;
608 
609 	for (i = 0; i < ex->num_phys; i++) {
610 		struct ex_phy *phy = &ex->ex_phy[i];
611 
612 		if (phy->phy_state == PHY_VACANT ||
613 		    phy->phy_state == PHY_NOT_PRESENT)
614 			continue;
615 
616 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
617 			sas_ex_disable_phy(dev, i);
618 	}
619 }
620 
621 static int sas_dev_present_in_domain(struct asd_sas_port *port,
622 					    u8 *sas_addr)
623 {
624 	struct domain_device *dev;
625 
626 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
627 		return 1;
628 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
629 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
630 			return 1;
631 	}
632 	return 0;
633 }
634 
635 #define RPEL_REQ_SIZE	16
636 #define RPEL_RESP_SIZE	32
637 int sas_smp_get_phy_events(struct sas_phy *phy)
638 {
639 	int res;
640 	u8 *req;
641 	u8 *resp;
642 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
643 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
644 
645 	req = alloc_smp_req(RPEL_REQ_SIZE);
646 	if (!req)
647 		return -ENOMEM;
648 
649 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
650 	if (!resp) {
651 		kfree(req);
652 		return -ENOMEM;
653 	}
654 
655 	req[1] = SMP_REPORT_PHY_ERR_LOG;
656 	req[9] = phy->number;
657 
658 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
659 			       resp, RPEL_RESP_SIZE);
660 
661 	if (res)
662 		goto out;
663 
664 	phy->invalid_dword_count = get_unaligned_be32(&resp[12]);
665 	phy->running_disparity_error_count = get_unaligned_be32(&resp[16]);
666 	phy->loss_of_dword_sync_count = get_unaligned_be32(&resp[20]);
667 	phy->phy_reset_problem_count = get_unaligned_be32(&resp[24]);
668 
669  out:
670 	kfree(req);
671 	kfree(resp);
672 	return res;
673 
674 }
675 
676 #ifdef CONFIG_SCSI_SAS_ATA
677 
678 #define RPS_REQ_SIZE  16
679 #define RPS_RESP_SIZE sizeof(struct smp_rps_resp)
680 
681 int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
682 			    struct smp_rps_resp *rps_resp)
683 {
684 	int res;
685 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
686 	u8 *resp = (u8 *)rps_resp;
687 
688 	if (!rps_req)
689 		return -ENOMEM;
690 
691 	rps_req[1] = SMP_REPORT_PHY_SATA;
692 	rps_req[9] = phy_id;
693 
694 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
695 			       rps_resp, RPS_RESP_SIZE);
696 
697 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
698 	 * standards cockup here.  sas-2 explicitly specifies the FIS
699 	 * should be encoded so that FIS type is in resp[24].
700 	 * However, some expanders endian reverse this.  Undo the
701 	 * reversal here */
702 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
703 		int i;
704 
705 		for (i = 0; i < 5; i++) {
706 			int j = 24 + (i*4);
707 			u8 a, b;
708 			a = resp[j + 0];
709 			b = resp[j + 1];
710 			resp[j + 0] = resp[j + 3];
711 			resp[j + 1] = resp[j + 2];
712 			resp[j + 2] = b;
713 			resp[j + 3] = a;
714 		}
715 	}
716 
717 	kfree(rps_req);
718 	return res;
719 }
720 #endif
721 
722 static void sas_ex_get_linkrate(struct domain_device *parent,
723 				       struct domain_device *child,
724 				       struct ex_phy *parent_phy)
725 {
726 	struct expander_device *parent_ex = &parent->ex_dev;
727 	struct sas_port *port;
728 	int i;
729 
730 	child->pathways = 0;
731 
732 	port = parent_phy->port;
733 
734 	for (i = 0; i < parent_ex->num_phys; i++) {
735 		struct ex_phy *phy = &parent_ex->ex_phy[i];
736 
737 		if (phy->phy_state == PHY_VACANT ||
738 		    phy->phy_state == PHY_NOT_PRESENT)
739 			continue;
740 
741 		if (sas_phy_match_dev_addr(child, phy)) {
742 			child->min_linkrate = min(parent->min_linkrate,
743 						  phy->linkrate);
744 			child->max_linkrate = max(parent->max_linkrate,
745 						  phy->linkrate);
746 			child->pathways++;
747 			sas_port_add_phy(port, phy->phy);
748 		}
749 	}
750 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
751 	child->pathways = min(child->pathways, parent->pathways);
752 }
753 
754 static int sas_ex_add_dev(struct domain_device *parent, struct ex_phy *phy,
755 			  struct domain_device *child, int phy_id)
756 {
757 	struct sas_rphy *rphy;
758 	int res;
759 
760 	child->dev_type = SAS_END_DEVICE;
761 	rphy = sas_end_device_alloc(phy->port);
762 	if (!rphy)
763 		return -ENOMEM;
764 
765 	child->tproto = phy->attached_tproto;
766 	sas_init_dev(child);
767 
768 	child->rphy = rphy;
769 	get_device(&rphy->dev);
770 	rphy->identify.phy_identifier = phy_id;
771 	sas_fill_in_rphy(child, rphy);
772 
773 	list_add_tail(&child->disco_list_node, &parent->port->disco_list);
774 
775 	res = sas_notify_lldd_dev_found(child);
776 	if (res) {
777 		pr_notice("notify lldd for device %016llx at %016llx:%02d returned 0x%x\n",
778 			  SAS_ADDR(child->sas_addr),
779 			  SAS_ADDR(parent->sas_addr), phy_id, res);
780 		sas_rphy_free(child->rphy);
781 		list_del(&child->disco_list_node);
782 		return res;
783 	}
784 
785 	return 0;
786 }
787 
788 static struct domain_device *sas_ex_discover_end_dev(
789 	struct domain_device *parent, int phy_id)
790 {
791 	struct expander_device *parent_ex = &parent->ex_dev;
792 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
793 	struct domain_device *child = NULL;
794 	int res;
795 
796 	if (phy->attached_sata_host || phy->attached_sata_ps)
797 		return NULL;
798 
799 	child = sas_alloc_device();
800 	if (!child)
801 		return NULL;
802 
803 	kref_get(&parent->kref);
804 	child->parent = parent;
805 	child->port   = parent->port;
806 	child->iproto = phy->attached_iproto;
807 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
808 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
809 	if (!phy->port) {
810 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
811 		if (unlikely(!phy->port))
812 			goto out_err;
813 		if (unlikely(sas_port_add(phy->port) != 0)) {
814 			sas_port_free(phy->port);
815 			goto out_err;
816 		}
817 	}
818 	sas_ex_get_linkrate(parent, child, phy);
819 	sas_device_set_phy(child, phy->port);
820 
821 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
822 		res = sas_ata_add_dev(parent, phy, child, phy_id);
823 	} else if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
824 		res = sas_ex_add_dev(parent, phy, child, phy_id);
825 	} else {
826 		pr_notice("target proto 0x%x at %016llx:0x%x not handled\n",
827 			  phy->attached_tproto, SAS_ADDR(parent->sas_addr),
828 			  phy_id);
829 		res = -ENODEV;
830 	}
831 
832 	if (res)
833 		goto out_free;
834 
835 	list_add_tail(&child->siblings, &parent_ex->children);
836 	return child;
837 
838  out_free:
839 	sas_port_delete(phy->port);
840  out_err:
841 	phy->port = NULL;
842 	sas_put_device(child);
843 	return NULL;
844 }
845 
846 /* See if this phy is part of a wide port */
847 static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
848 {
849 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
850 	int i;
851 
852 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
853 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
854 
855 		if (ephy == phy)
856 			continue;
857 
858 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
859 			    SAS_ADDR_SIZE) && ephy->port) {
860 			sas_port_add_phy(ephy->port, phy->phy);
861 			phy->port = ephy->port;
862 			phy->phy_state = PHY_DEVICE_DISCOVERED;
863 			return true;
864 		}
865 	}
866 
867 	return false;
868 }
869 
870 static struct domain_device *sas_ex_discover_expander(
871 	struct domain_device *parent, int phy_id)
872 {
873 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
874 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
875 	struct domain_device *child = NULL;
876 	struct sas_rphy *rphy;
877 	struct sas_expander_device *edev;
878 	struct asd_sas_port *port;
879 	int res;
880 
881 	if (phy->routing_attr == DIRECT_ROUTING) {
882 		pr_warn("ex %016llx:%02d:D <--> ex %016llx:0x%x is not allowed\n",
883 			SAS_ADDR(parent->sas_addr), phy_id,
884 			SAS_ADDR(phy->attached_sas_addr),
885 			phy->attached_phy_id);
886 		return NULL;
887 	}
888 	child = sas_alloc_device();
889 	if (!child)
890 		return NULL;
891 
892 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
893 	/* FIXME: better error handling */
894 	BUG_ON(sas_port_add(phy->port) != 0);
895 
896 
897 	switch (phy->attached_dev_type) {
898 	case SAS_EDGE_EXPANDER_DEVICE:
899 		rphy = sas_expander_alloc(phy->port,
900 					  SAS_EDGE_EXPANDER_DEVICE);
901 		break;
902 	case SAS_FANOUT_EXPANDER_DEVICE:
903 		rphy = sas_expander_alloc(phy->port,
904 					  SAS_FANOUT_EXPANDER_DEVICE);
905 		break;
906 	default:
907 		rphy = NULL;	/* shut gcc up */
908 		BUG();
909 	}
910 	port = parent->port;
911 	child->rphy = rphy;
912 	get_device(&rphy->dev);
913 	edev = rphy_to_expander_device(rphy);
914 	child->dev_type = phy->attached_dev_type;
915 	kref_get(&parent->kref);
916 	child->parent = parent;
917 	child->port = port;
918 	child->iproto = phy->attached_iproto;
919 	child->tproto = phy->attached_tproto;
920 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
921 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
922 	sas_ex_get_linkrate(parent, child, phy);
923 	edev->level = parent_ex->level + 1;
924 	parent->port->disc.max_level = max(parent->port->disc.max_level,
925 					   edev->level);
926 	sas_init_dev(child);
927 	sas_fill_in_rphy(child, rphy);
928 	sas_rphy_add(rphy);
929 
930 	spin_lock_irq(&parent->port->dev_list_lock);
931 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
932 	spin_unlock_irq(&parent->port->dev_list_lock);
933 
934 	res = sas_discover_expander(child);
935 	if (res) {
936 		sas_rphy_delete(rphy);
937 		spin_lock_irq(&parent->port->dev_list_lock);
938 		list_del(&child->dev_list_node);
939 		spin_unlock_irq(&parent->port->dev_list_lock);
940 		sas_put_device(child);
941 		sas_port_delete(phy->port);
942 		phy->port = NULL;
943 		return NULL;
944 	}
945 	list_add_tail(&child->siblings, &parent->ex_dev.children);
946 	return child;
947 }
948 
949 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
950 {
951 	struct expander_device *ex = &dev->ex_dev;
952 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
953 	struct domain_device *child = NULL;
954 	int res = 0;
955 
956 	/* Phy state */
957 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
958 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
959 			res = sas_ex_phy_discover(dev, phy_id);
960 		if (res)
961 			return res;
962 	}
963 
964 	/* Parent and domain coherency */
965 	if (!dev->parent && sas_phy_match_port_addr(dev->port, ex_phy)) {
966 		sas_add_parent_port(dev, phy_id);
967 		return 0;
968 	}
969 	if (dev->parent && sas_phy_match_dev_addr(dev->parent, ex_phy)) {
970 		sas_add_parent_port(dev, phy_id);
971 		if (ex_phy->routing_attr == TABLE_ROUTING)
972 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
973 		return 0;
974 	}
975 
976 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
977 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
978 
979 	if (ex_phy->attached_dev_type == SAS_PHY_UNUSED) {
980 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
981 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
982 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
983 		}
984 		return 0;
985 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
986 		return 0;
987 
988 	if (ex_phy->attached_dev_type != SAS_END_DEVICE &&
989 	    ex_phy->attached_dev_type != SAS_FANOUT_EXPANDER_DEVICE &&
990 	    ex_phy->attached_dev_type != SAS_EDGE_EXPANDER_DEVICE &&
991 	    ex_phy->attached_dev_type != SAS_SATA_PENDING) {
992 		pr_warn("unknown device type(0x%x) attached to ex %016llx phy%02d\n",
993 			ex_phy->attached_dev_type,
994 			SAS_ADDR(dev->sas_addr),
995 			phy_id);
996 		return 0;
997 	}
998 
999 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
1000 	if (res) {
1001 		pr_notice("configure routing for dev %016llx reported 0x%x. Forgotten\n",
1002 			  SAS_ADDR(ex_phy->attached_sas_addr), res);
1003 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
1004 		return res;
1005 	}
1006 
1007 	if (sas_ex_join_wide_port(dev, phy_id)) {
1008 		pr_debug("Attaching ex phy%02d to wide port %016llx\n",
1009 			 phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
1010 		return res;
1011 	}
1012 
1013 	switch (ex_phy->attached_dev_type) {
1014 	case SAS_END_DEVICE:
1015 	case SAS_SATA_PENDING:
1016 		child = sas_ex_discover_end_dev(dev, phy_id);
1017 		break;
1018 	case SAS_FANOUT_EXPANDER_DEVICE:
1019 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
1020 			pr_debug("second fanout expander %016llx phy%02d attached to ex %016llx phy%02d\n",
1021 				 SAS_ADDR(ex_phy->attached_sas_addr),
1022 				 ex_phy->attached_phy_id,
1023 				 SAS_ADDR(dev->sas_addr),
1024 				 phy_id);
1025 			sas_ex_disable_phy(dev, phy_id);
1026 			return res;
1027 		} else
1028 			memcpy(dev->port->disc.fanout_sas_addr,
1029 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
1030 		fallthrough;
1031 	case SAS_EDGE_EXPANDER_DEVICE:
1032 		child = sas_ex_discover_expander(dev, phy_id);
1033 		break;
1034 	default:
1035 		break;
1036 	}
1037 
1038 	if (!child)
1039 		pr_notice("ex %016llx phy%02d failed to discover\n",
1040 			  SAS_ADDR(dev->sas_addr), phy_id);
1041 	return res;
1042 }
1043 
1044 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
1045 {
1046 	struct expander_device *ex = &dev->ex_dev;
1047 	int i;
1048 
1049 	for (i = 0; i < ex->num_phys; i++) {
1050 		struct ex_phy *phy = &ex->ex_phy[i];
1051 
1052 		if (phy->phy_state == PHY_VACANT ||
1053 		    phy->phy_state == PHY_NOT_PRESENT)
1054 			continue;
1055 
1056 		if (dev_is_expander(phy->attached_dev_type) &&
1057 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1058 
1059 			memcpy(sub_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
1060 
1061 			return 1;
1062 		}
1063 	}
1064 	return 0;
1065 }
1066 
1067 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1068 {
1069 	struct expander_device *ex = &dev->ex_dev;
1070 	struct domain_device *child;
1071 	u8 sub_addr[SAS_ADDR_SIZE] = {0, };
1072 
1073 	list_for_each_entry(child, &ex->children, siblings) {
1074 		if (!dev_is_expander(child->dev_type))
1075 			continue;
1076 		if (sub_addr[0] == 0) {
1077 			sas_find_sub_addr(child, sub_addr);
1078 			continue;
1079 		} else {
1080 			u8 s2[SAS_ADDR_SIZE];
1081 
1082 			if (sas_find_sub_addr(child, s2) &&
1083 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1084 
1085 				pr_notice("ex %016llx->%016llx-?->%016llx diverges from subtractive boundary %016llx\n",
1086 					  SAS_ADDR(dev->sas_addr),
1087 					  SAS_ADDR(child->sas_addr),
1088 					  SAS_ADDR(s2),
1089 					  SAS_ADDR(sub_addr));
1090 
1091 				sas_ex_disable_port(child, s2);
1092 			}
1093 		}
1094 	}
1095 	return 0;
1096 }
1097 /**
1098  * sas_ex_discover_devices - discover devices attached to this expander
1099  * @dev: pointer to the expander domain device
1100  * @single: if you want to do a single phy, else set to -1;
1101  *
1102  * Configure this expander for use with its devices and register the
1103  * devices of this expander.
1104  */
1105 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1106 {
1107 	struct expander_device *ex = &dev->ex_dev;
1108 	int i = 0, end = ex->num_phys;
1109 	int res = 0;
1110 
1111 	if (0 <= single && single < end) {
1112 		i = single;
1113 		end = i+1;
1114 	}
1115 
1116 	for ( ; i < end; i++) {
1117 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1118 
1119 		if (ex_phy->phy_state == PHY_VACANT ||
1120 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1121 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1122 			continue;
1123 
1124 		switch (ex_phy->linkrate) {
1125 		case SAS_PHY_DISABLED:
1126 		case SAS_PHY_RESET_PROBLEM:
1127 		case SAS_SATA_PORT_SELECTOR:
1128 			continue;
1129 		default:
1130 			res = sas_ex_discover_dev(dev, i);
1131 			if (res)
1132 				break;
1133 			continue;
1134 		}
1135 	}
1136 
1137 	if (!res)
1138 		sas_check_level_subtractive_boundary(dev);
1139 
1140 	return res;
1141 }
1142 
1143 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1144 {
1145 	struct expander_device *ex = &dev->ex_dev;
1146 	int i;
1147 	u8  *sub_sas_addr = NULL;
1148 
1149 	if (dev->dev_type != SAS_EDGE_EXPANDER_DEVICE)
1150 		return 0;
1151 
1152 	for (i = 0; i < ex->num_phys; i++) {
1153 		struct ex_phy *phy = &ex->ex_phy[i];
1154 
1155 		if (phy->phy_state == PHY_VACANT ||
1156 		    phy->phy_state == PHY_NOT_PRESENT)
1157 			continue;
1158 
1159 		if (dev_is_expander(phy->attached_dev_type) &&
1160 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1161 
1162 			if (!sub_sas_addr)
1163 				sub_sas_addr = &phy->attached_sas_addr[0];
1164 			else if (SAS_ADDR(sub_sas_addr) !=
1165 				 SAS_ADDR(phy->attached_sas_addr)) {
1166 
1167 				pr_notice("ex %016llx phy%02d diverges(%016llx) on subtractive boundary(%016llx). Disabled\n",
1168 					  SAS_ADDR(dev->sas_addr), i,
1169 					  SAS_ADDR(phy->attached_sas_addr),
1170 					  SAS_ADDR(sub_sas_addr));
1171 				sas_ex_disable_phy(dev, i);
1172 			}
1173 		}
1174 	}
1175 	return 0;
1176 }
1177 
1178 static void sas_print_parent_topology_bug(struct domain_device *child,
1179 						 struct ex_phy *parent_phy,
1180 						 struct ex_phy *child_phy)
1181 {
1182 	static const char *ex_type[] = {
1183 		[SAS_EDGE_EXPANDER_DEVICE] = "edge",
1184 		[SAS_FANOUT_EXPANDER_DEVICE] = "fanout",
1185 	};
1186 	struct domain_device *parent = child->parent;
1187 
1188 	pr_notice("%s ex %016llx phy%02d <--> %s ex %016llx phy%02d has %c:%c routing link!\n",
1189 		  ex_type[parent->dev_type],
1190 		  SAS_ADDR(parent->sas_addr),
1191 		  parent_phy->phy_id,
1192 
1193 		  ex_type[child->dev_type],
1194 		  SAS_ADDR(child->sas_addr),
1195 		  child_phy->phy_id,
1196 
1197 		  sas_route_char(parent, parent_phy),
1198 		  sas_route_char(child, child_phy));
1199 }
1200 
1201 static bool sas_eeds_valid(struct domain_device *parent,
1202 			   struct domain_device *child)
1203 {
1204 	struct sas_discovery *disc = &parent->port->disc;
1205 
1206 	return (SAS_ADDR(disc->eeds_a) == SAS_ADDR(parent->sas_addr) ||
1207 		SAS_ADDR(disc->eeds_a) == SAS_ADDR(child->sas_addr)) &&
1208 	       (SAS_ADDR(disc->eeds_b) == SAS_ADDR(parent->sas_addr) ||
1209 		SAS_ADDR(disc->eeds_b) == SAS_ADDR(child->sas_addr));
1210 }
1211 
1212 static int sas_check_eeds(struct domain_device *child,
1213 			  struct ex_phy *parent_phy,
1214 			  struct ex_phy *child_phy)
1215 {
1216 	int res = 0;
1217 	struct domain_device *parent = child->parent;
1218 	struct sas_discovery *disc = &parent->port->disc;
1219 
1220 	if (SAS_ADDR(disc->fanout_sas_addr) != 0) {
1221 		res = -ENODEV;
1222 		pr_warn("edge ex %016llx phy S:%02d <--> edge ex %016llx phy S:%02d, while there is a fanout ex %016llx\n",
1223 			SAS_ADDR(parent->sas_addr),
1224 			parent_phy->phy_id,
1225 			SAS_ADDR(child->sas_addr),
1226 			child_phy->phy_id,
1227 			SAS_ADDR(disc->fanout_sas_addr));
1228 	} else if (SAS_ADDR(disc->eeds_a) == 0) {
1229 		memcpy(disc->eeds_a, parent->sas_addr, SAS_ADDR_SIZE);
1230 		memcpy(disc->eeds_b, child->sas_addr, SAS_ADDR_SIZE);
1231 	} else if (!sas_eeds_valid(parent, child)) {
1232 		res = -ENODEV;
1233 		pr_warn("edge ex %016llx phy%02d <--> edge ex %016llx phy%02d link forms a third EEDS!\n",
1234 			SAS_ADDR(parent->sas_addr),
1235 			parent_phy->phy_id,
1236 			SAS_ADDR(child->sas_addr),
1237 			child_phy->phy_id);
1238 	}
1239 
1240 	return res;
1241 }
1242 
1243 static int sas_check_edge_expander_topo(struct domain_device *child,
1244 					struct ex_phy *parent_phy)
1245 {
1246 	struct expander_device *child_ex = &child->ex_dev;
1247 	struct expander_device *parent_ex = &child->parent->ex_dev;
1248 	struct ex_phy *child_phy;
1249 
1250 	child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1251 
1252 	if (child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1253 		if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1254 		    child_phy->routing_attr != TABLE_ROUTING)
1255 			goto error;
1256 	} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1257 		if (child_phy->routing_attr == SUBTRACTIVE_ROUTING)
1258 			return sas_check_eeds(child, parent_phy, child_phy);
1259 		else if (child_phy->routing_attr != TABLE_ROUTING)
1260 			goto error;
1261 	} else if (parent_phy->routing_attr == TABLE_ROUTING) {
1262 		if (child_phy->routing_attr != SUBTRACTIVE_ROUTING &&
1263 		    (child_phy->routing_attr != TABLE_ROUTING ||
1264 		     !child_ex->t2t_supp || !parent_ex->t2t_supp))
1265 			goto error;
1266 	}
1267 
1268 	return 0;
1269 error:
1270 	sas_print_parent_topology_bug(child, parent_phy, child_phy);
1271 	return -ENODEV;
1272 }
1273 
1274 static int sas_check_fanout_expander_topo(struct domain_device *child,
1275 					  struct ex_phy *parent_phy)
1276 {
1277 	struct expander_device *child_ex = &child->ex_dev;
1278 	struct ex_phy *child_phy;
1279 
1280 	child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1281 
1282 	if (parent_phy->routing_attr == TABLE_ROUTING &&
1283 	    child_phy->routing_attr == SUBTRACTIVE_ROUTING)
1284 		return 0;
1285 
1286 	sas_print_parent_topology_bug(child, parent_phy, child_phy);
1287 
1288 	return -ENODEV;
1289 }
1290 
1291 static int sas_check_parent_topology(struct domain_device *child)
1292 {
1293 	struct expander_device *parent_ex;
1294 	int i;
1295 	int res = 0;
1296 
1297 	if (!child->parent)
1298 		return 0;
1299 
1300 	if (!dev_is_expander(child->parent->dev_type))
1301 		return 0;
1302 
1303 	parent_ex = &child->parent->ex_dev;
1304 
1305 	for (i = 0; i < parent_ex->num_phys; i++) {
1306 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1307 
1308 		if (parent_phy->phy_state == PHY_VACANT ||
1309 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1310 			continue;
1311 
1312 		if (!sas_phy_match_dev_addr(child, parent_phy))
1313 			continue;
1314 
1315 		switch (child->parent->dev_type) {
1316 		case SAS_EDGE_EXPANDER_DEVICE:
1317 			if (sas_check_edge_expander_topo(child, parent_phy))
1318 				res = -ENODEV;
1319 			break;
1320 		case SAS_FANOUT_EXPANDER_DEVICE:
1321 			if (sas_check_fanout_expander_topo(child, parent_phy))
1322 				res = -ENODEV;
1323 			break;
1324 		default:
1325 			break;
1326 		}
1327 	}
1328 
1329 	return res;
1330 }
1331 
1332 #define RRI_REQ_SIZE  16
1333 #define RRI_RESP_SIZE 44
1334 
1335 static int sas_configure_present(struct domain_device *dev, int phy_id,
1336 				 u8 *sas_addr, int *index, int *present)
1337 {
1338 	int i, res = 0;
1339 	struct expander_device *ex = &dev->ex_dev;
1340 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1341 	u8 *rri_req;
1342 	u8 *rri_resp;
1343 
1344 	*present = 0;
1345 	*index = 0;
1346 
1347 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1348 	if (!rri_req)
1349 		return -ENOMEM;
1350 
1351 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1352 	if (!rri_resp) {
1353 		kfree(rri_req);
1354 		return -ENOMEM;
1355 	}
1356 
1357 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1358 	rri_req[9] = phy_id;
1359 
1360 	for (i = 0; i < ex->max_route_indexes ; i++) {
1361 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1362 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1363 				       RRI_RESP_SIZE);
1364 		if (res)
1365 			goto out;
1366 		res = rri_resp[2];
1367 		if (res == SMP_RESP_NO_INDEX) {
1368 			pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1369 				SAS_ADDR(dev->sas_addr), phy_id, i);
1370 			goto out;
1371 		} else if (res != SMP_RESP_FUNC_ACC) {
1372 			pr_notice("%s: dev %016llx phy%02d index 0x%x result 0x%x\n",
1373 				  __func__, SAS_ADDR(dev->sas_addr), phy_id,
1374 				  i, res);
1375 			goto out;
1376 		}
1377 		if (SAS_ADDR(sas_addr) != 0) {
1378 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1379 				*index = i;
1380 				if ((rri_resp[12] & 0x80) == 0x80)
1381 					*present = 0;
1382 				else
1383 					*present = 1;
1384 				goto out;
1385 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1386 				*index = i;
1387 				*present = 0;
1388 				goto out;
1389 			}
1390 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1391 			   phy->last_da_index < i) {
1392 			phy->last_da_index = i;
1393 			*index = i;
1394 			*present = 0;
1395 			goto out;
1396 		}
1397 	}
1398 	res = -1;
1399 out:
1400 	kfree(rri_req);
1401 	kfree(rri_resp);
1402 	return res;
1403 }
1404 
1405 #define CRI_REQ_SIZE  44
1406 #define CRI_RESP_SIZE  8
1407 
1408 static int sas_configure_set(struct domain_device *dev, int phy_id,
1409 			     u8 *sas_addr, int index, int include)
1410 {
1411 	int res;
1412 	u8 *cri_req;
1413 	u8 *cri_resp;
1414 
1415 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1416 	if (!cri_req)
1417 		return -ENOMEM;
1418 
1419 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1420 	if (!cri_resp) {
1421 		kfree(cri_req);
1422 		return -ENOMEM;
1423 	}
1424 
1425 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1426 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1427 	cri_req[9] = phy_id;
1428 	if (SAS_ADDR(sas_addr) == 0 || !include)
1429 		cri_req[12] |= 0x80;
1430 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1431 
1432 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1433 			       CRI_RESP_SIZE);
1434 	if (res)
1435 		goto out;
1436 	res = cri_resp[2];
1437 	if (res == SMP_RESP_NO_INDEX) {
1438 		pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1439 			SAS_ADDR(dev->sas_addr), phy_id, index);
1440 	}
1441 out:
1442 	kfree(cri_req);
1443 	kfree(cri_resp);
1444 	return res;
1445 }
1446 
1447 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1448 				    u8 *sas_addr, int include)
1449 {
1450 	int index;
1451 	int present;
1452 	int res;
1453 
1454 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1455 	if (res)
1456 		return res;
1457 	if (include ^ present)
1458 		return sas_configure_set(dev, phy_id, sas_addr, index,
1459 					 include);
1460 
1461 	return res;
1462 }
1463 
1464 /**
1465  * sas_configure_parent - configure routing table of parent
1466  * @parent: parent expander
1467  * @child: child expander
1468  * @sas_addr: SAS port identifier of device directly attached to child
1469  * @include: whether or not to include @child in the expander routing table
1470  */
1471 static int sas_configure_parent(struct domain_device *parent,
1472 				struct domain_device *child,
1473 				u8 *sas_addr, int include)
1474 {
1475 	struct expander_device *ex_parent = &parent->ex_dev;
1476 	int res = 0;
1477 	int i;
1478 
1479 	if (parent->parent) {
1480 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1481 					   include);
1482 		if (res)
1483 			return res;
1484 	}
1485 
1486 	if (ex_parent->conf_route_table == 0) {
1487 		pr_debug("ex %016llx has self-configuring routing table\n",
1488 			 SAS_ADDR(parent->sas_addr));
1489 		return 0;
1490 	}
1491 
1492 	for (i = 0; i < ex_parent->num_phys; i++) {
1493 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1494 
1495 		if ((phy->routing_attr == TABLE_ROUTING) &&
1496 		    sas_phy_match_dev_addr(child, phy)) {
1497 			res = sas_configure_phy(parent, i, sas_addr, include);
1498 			if (res)
1499 				return res;
1500 		}
1501 	}
1502 
1503 	return res;
1504 }
1505 
1506 /**
1507  * sas_configure_routing - configure routing
1508  * @dev: expander device
1509  * @sas_addr: port identifier of device directly attached to the expander device
1510  */
1511 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1512 {
1513 	if (dev->parent)
1514 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1515 	return 0;
1516 }
1517 
1518 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1519 {
1520 	if (dev->parent)
1521 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1522 	return 0;
1523 }
1524 
1525 /**
1526  * sas_discover_expander - expander discovery
1527  * @dev: pointer to expander domain device
1528  *
1529  * See comment in sas_discover_sata().
1530  */
1531 static int sas_discover_expander(struct domain_device *dev)
1532 {
1533 	int res;
1534 
1535 	res = sas_notify_lldd_dev_found(dev);
1536 	if (res)
1537 		return res;
1538 
1539 	res = sas_ex_general(dev);
1540 	if (res)
1541 		goto out_err;
1542 	res = sas_ex_manuf_info(dev);
1543 	if (res)
1544 		goto out_err;
1545 
1546 	res = sas_expander_discover(dev);
1547 	if (res) {
1548 		pr_warn("expander %016llx discovery failed(0x%x)\n",
1549 			SAS_ADDR(dev->sas_addr), res);
1550 		goto out_err;
1551 	}
1552 
1553 	sas_check_ex_subtractive_boundary(dev);
1554 	res = sas_check_parent_topology(dev);
1555 	if (res)
1556 		goto out_err;
1557 	return 0;
1558 out_err:
1559 	sas_notify_lldd_dev_gone(dev);
1560 	return res;
1561 }
1562 
1563 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1564 {
1565 	int res = 0;
1566 	struct domain_device *dev;
1567 
1568 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1569 		if (dev_is_expander(dev->dev_type)) {
1570 			struct sas_expander_device *ex =
1571 				rphy_to_expander_device(dev->rphy);
1572 
1573 			if (level == ex->level)
1574 				res = sas_ex_discover_devices(dev, -1);
1575 			else if (level > 0)
1576 				res = sas_ex_discover_devices(port->port_dev, -1);
1577 
1578 		}
1579 	}
1580 
1581 	return res;
1582 }
1583 
1584 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1585 {
1586 	int res;
1587 	int level;
1588 
1589 	do {
1590 		level = port->disc.max_level;
1591 		res = sas_ex_level_discovery(port, level);
1592 		mb();
1593 	} while (level < port->disc.max_level);
1594 
1595 	return res;
1596 }
1597 
1598 int sas_discover_root_expander(struct domain_device *dev)
1599 {
1600 	int res;
1601 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1602 
1603 	res = sas_rphy_add(dev->rphy);
1604 	if (res)
1605 		goto out_err;
1606 
1607 	ex->level = dev->port->disc.max_level; /* 0 */
1608 	res = sas_discover_expander(dev);
1609 	if (res)
1610 		goto out_err2;
1611 
1612 	sas_ex_bfs_disc(dev->port);
1613 
1614 	return res;
1615 
1616 out_err2:
1617 	sas_rphy_remove(dev->rphy);
1618 out_err:
1619 	return res;
1620 }
1621 
1622 /* ---------- Domain revalidation ---------- */
1623 
1624 static int sas_get_phy_discover(struct domain_device *dev,
1625 				int phy_id, struct smp_disc_resp *disc_resp)
1626 {
1627 	int res;
1628 	u8 *disc_req;
1629 
1630 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1631 	if (!disc_req)
1632 		return -ENOMEM;
1633 
1634 	disc_req[1] = SMP_DISCOVER;
1635 	disc_req[9] = phy_id;
1636 
1637 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1638 			       disc_resp, DISCOVER_RESP_SIZE);
1639 	if (res)
1640 		goto out;
1641 	if (disc_resp->result != SMP_RESP_FUNC_ACC)
1642 		res = disc_resp->result;
1643 out:
1644 	kfree(disc_req);
1645 	return res;
1646 }
1647 
1648 static int sas_get_phy_change_count(struct domain_device *dev,
1649 				    int phy_id, int *pcc)
1650 {
1651 	int res;
1652 	struct smp_disc_resp *disc_resp;
1653 
1654 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1655 	if (!disc_resp)
1656 		return -ENOMEM;
1657 
1658 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1659 	if (!res)
1660 		*pcc = disc_resp->disc.change_count;
1661 
1662 	kfree(disc_resp);
1663 	return res;
1664 }
1665 
1666 int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
1667 			     u8 *sas_addr, enum sas_device_type *type)
1668 {
1669 	int res;
1670 	struct smp_disc_resp *disc_resp;
1671 
1672 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1673 	if (!disc_resp)
1674 		return -ENOMEM;
1675 
1676 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1677 	if (res == 0) {
1678 		memcpy(sas_addr, disc_resp->disc.attached_sas_addr,
1679 		       SAS_ADDR_SIZE);
1680 		*type = to_dev_type(&disc_resp->disc);
1681 		if (*type == 0)
1682 			memset(sas_addr, 0, SAS_ADDR_SIZE);
1683 	}
1684 	kfree(disc_resp);
1685 	return res;
1686 }
1687 
1688 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1689 			      int from_phy, bool update)
1690 {
1691 	struct expander_device *ex = &dev->ex_dev;
1692 	int res = 0;
1693 	int i;
1694 
1695 	for (i = from_phy; i < ex->num_phys; i++) {
1696 		int phy_change_count = 0;
1697 
1698 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1699 		switch (res) {
1700 		case SMP_RESP_PHY_VACANT:
1701 		case SMP_RESP_NO_PHY:
1702 			continue;
1703 		case SMP_RESP_FUNC_ACC:
1704 			break;
1705 		default:
1706 			return res;
1707 		}
1708 
1709 		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1710 			if (update)
1711 				ex->ex_phy[i].phy_change_count =
1712 					phy_change_count;
1713 			*phy_id = i;
1714 			return 0;
1715 		}
1716 	}
1717 	return 0;
1718 }
1719 
1720 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1721 {
1722 	int res;
1723 	u8  *rg_req;
1724 	struct smp_rg_resp  *rg_resp;
1725 
1726 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1727 	if (!rg_req)
1728 		return -ENOMEM;
1729 
1730 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1731 	if (!rg_resp) {
1732 		kfree(rg_req);
1733 		return -ENOMEM;
1734 	}
1735 
1736 	rg_req[1] = SMP_REPORT_GENERAL;
1737 
1738 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1739 			       RG_RESP_SIZE);
1740 	if (res)
1741 		goto out;
1742 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1743 		res = rg_resp->result;
1744 		goto out;
1745 	}
1746 
1747 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1748 out:
1749 	kfree(rg_resp);
1750 	kfree(rg_req);
1751 	return res;
1752 }
1753 /**
1754  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1755  * @dev:domain device to be detect.
1756  * @src_dev: the device which originated BROADCAST(CHANGE).
1757  *
1758  * Add self-configuration expander support. Suppose two expander cascading,
1759  * when the first level expander is self-configuring, hotplug the disks in
1760  * second level expander, BROADCAST(CHANGE) will not only be originated
1761  * in the second level expander, but also be originated in the first level
1762  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1763  * expander changed count in two level expanders will all increment at least
1764  * once, but the phy which chang count has changed is the source device which
1765  * we concerned.
1766  */
1767 
1768 static int sas_find_bcast_dev(struct domain_device *dev,
1769 			      struct domain_device **src_dev)
1770 {
1771 	struct expander_device *ex = &dev->ex_dev;
1772 	int ex_change_count = -1;
1773 	int phy_id = -1;
1774 	int res;
1775 	struct domain_device *ch;
1776 
1777 	res = sas_get_ex_change_count(dev, &ex_change_count);
1778 	if (res)
1779 		goto out;
1780 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1781 		/* Just detect if this expander phys phy change count changed,
1782 		* in order to determine if this expander originate BROADCAST,
1783 		* and do not update phy change count field in our structure.
1784 		*/
1785 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1786 		if (phy_id != -1) {
1787 			*src_dev = dev;
1788 			ex->ex_change_count = ex_change_count;
1789 			pr_info("ex %016llx phy%02d change count has changed\n",
1790 				SAS_ADDR(dev->sas_addr), phy_id);
1791 			return res;
1792 		} else
1793 			pr_info("ex %016llx phys DID NOT change\n",
1794 				SAS_ADDR(dev->sas_addr));
1795 	}
1796 	list_for_each_entry(ch, &ex->children, siblings) {
1797 		if (dev_is_expander(ch->dev_type)) {
1798 			res = sas_find_bcast_dev(ch, src_dev);
1799 			if (*src_dev)
1800 				return res;
1801 		}
1802 	}
1803 out:
1804 	return res;
1805 }
1806 
1807 static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
1808 {
1809 	struct expander_device *ex = &dev->ex_dev;
1810 	struct domain_device *child, *n;
1811 
1812 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1813 		set_bit(SAS_DEV_GONE, &child->state);
1814 		if (dev_is_expander(child->dev_type))
1815 			sas_unregister_ex_tree(port, child);
1816 		else
1817 			sas_unregister_dev(port, child);
1818 	}
1819 	sas_unregister_dev(port, dev);
1820 }
1821 
1822 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1823 					 int phy_id, bool last)
1824 {
1825 	struct expander_device *ex_dev = &parent->ex_dev;
1826 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1827 	struct domain_device *child, *n, *found = NULL;
1828 	if (last) {
1829 		list_for_each_entry_safe(child, n,
1830 			&ex_dev->children, siblings) {
1831 			if (sas_phy_match_dev_addr(child, phy)) {
1832 				set_bit(SAS_DEV_GONE, &child->state);
1833 				if (dev_is_expander(child->dev_type))
1834 					sas_unregister_ex_tree(parent->port, child);
1835 				else
1836 					sas_unregister_dev(parent->port, child);
1837 				found = child;
1838 				break;
1839 			}
1840 		}
1841 		sas_disable_routing(parent, phy->attached_sas_addr);
1842 	}
1843 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1844 	if (phy->port) {
1845 		sas_port_delete_phy(phy->port, phy->phy);
1846 		sas_device_set_phy(found, phy->port);
1847 		if (phy->port->num_phys == 0)
1848 			list_add_tail(&phy->port->del_list,
1849 				&parent->port->sas_port_del_list);
1850 		phy->port = NULL;
1851 	}
1852 }
1853 
1854 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1855 					  const int level)
1856 {
1857 	struct expander_device *ex_root = &root->ex_dev;
1858 	struct domain_device *child;
1859 	int res = 0;
1860 
1861 	list_for_each_entry(child, &ex_root->children, siblings) {
1862 		if (dev_is_expander(child->dev_type)) {
1863 			struct sas_expander_device *ex =
1864 				rphy_to_expander_device(child->rphy);
1865 
1866 			if (level > ex->level)
1867 				res = sas_discover_bfs_by_root_level(child,
1868 								     level);
1869 			else if (level == ex->level)
1870 				res = sas_ex_discover_devices(child, -1);
1871 		}
1872 	}
1873 	return res;
1874 }
1875 
1876 static int sas_discover_bfs_by_root(struct domain_device *dev)
1877 {
1878 	int res;
1879 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1880 	int level = ex->level+1;
1881 
1882 	res = sas_ex_discover_devices(dev, -1);
1883 	if (res)
1884 		goto out;
1885 	do {
1886 		res = sas_discover_bfs_by_root_level(dev, level);
1887 		mb();
1888 		level += 1;
1889 	} while (level <= dev->port->disc.max_level);
1890 out:
1891 	return res;
1892 }
1893 
1894 static int sas_discover_new(struct domain_device *dev, int phy_id)
1895 {
1896 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1897 	struct domain_device *child;
1898 	int res;
1899 
1900 	pr_debug("ex %016llx phy%02d new device attached\n",
1901 		 SAS_ADDR(dev->sas_addr), phy_id);
1902 	res = sas_ex_phy_discover(dev, phy_id);
1903 	if (res)
1904 		return res;
1905 
1906 	if (sas_ex_join_wide_port(dev, phy_id))
1907 		return 0;
1908 
1909 	res = sas_ex_discover_devices(dev, phy_id);
1910 	if (res)
1911 		return res;
1912 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1913 		if (sas_phy_match_dev_addr(child, ex_phy)) {
1914 			if (dev_is_expander(child->dev_type))
1915 				res = sas_discover_bfs_by_root(child);
1916 			break;
1917 		}
1918 	}
1919 	return res;
1920 }
1921 
1922 static bool dev_type_flutter(enum sas_device_type new, enum sas_device_type old)
1923 {
1924 	if (old == new)
1925 		return true;
1926 
1927 	/* treat device directed resets as flutter, if we went
1928 	 * SAS_END_DEVICE to SAS_SATA_PENDING the link needs recovery
1929 	 */
1930 	if ((old == SAS_SATA_PENDING && new == SAS_END_DEVICE) ||
1931 	    (old == SAS_END_DEVICE && new == SAS_SATA_PENDING))
1932 		return true;
1933 
1934 	return false;
1935 }
1936 
1937 static int sas_rediscover_dev(struct domain_device *dev, int phy_id,
1938 			      bool last, int sibling)
1939 {
1940 	struct expander_device *ex = &dev->ex_dev;
1941 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1942 	enum sas_device_type type = SAS_PHY_UNUSED;
1943 	u8 sas_addr[SAS_ADDR_SIZE];
1944 	char msg[80] = "";
1945 	int res;
1946 
1947 	if (!last)
1948 		sprintf(msg, ", part of a wide port with phy%02d", sibling);
1949 
1950 	pr_debug("ex %016llx rediscovering phy%02d%s\n",
1951 		 SAS_ADDR(dev->sas_addr), phy_id, msg);
1952 
1953 	memset(sas_addr, 0, SAS_ADDR_SIZE);
1954 	res = sas_get_phy_attached_dev(dev, phy_id, sas_addr, &type);
1955 	switch (res) {
1956 	case SMP_RESP_NO_PHY:
1957 		phy->phy_state = PHY_NOT_PRESENT;
1958 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1959 		return res;
1960 	case SMP_RESP_PHY_VACANT:
1961 		phy->phy_state = PHY_VACANT;
1962 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1963 		return res;
1964 	case SMP_RESP_FUNC_ACC:
1965 		break;
1966 	case -ECOMM:
1967 		break;
1968 	default:
1969 		return res;
1970 	}
1971 
1972 	if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM)) {
1973 		phy->phy_state = PHY_EMPTY;
1974 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1975 		/*
1976 		 * Even though the PHY is empty, for convenience we discover
1977 		 * the PHY to update the PHY info, like negotiated linkrate.
1978 		 */
1979 		sas_ex_phy_discover(dev, phy_id);
1980 		return res;
1981 	} else if (SAS_ADDR(sas_addr) == SAS_ADDR(phy->attached_sas_addr) &&
1982 		   dev_type_flutter(type, phy->attached_dev_type)) {
1983 		struct domain_device *ata_dev = sas_ex_to_ata(dev, phy_id);
1984 		char *action = "";
1985 
1986 		sas_ex_phy_discover(dev, phy_id);
1987 
1988 		if (ata_dev && phy->attached_dev_type == SAS_SATA_PENDING)
1989 			action = ", needs recovery";
1990 		pr_debug("ex %016llx phy%02d broadcast flutter%s\n",
1991 			 SAS_ADDR(dev->sas_addr), phy_id, action);
1992 		return res;
1993 	}
1994 
1995 	/* we always have to delete the old device when we went here */
1996 	pr_info("ex %016llx phy%02d replace %016llx\n",
1997 		SAS_ADDR(dev->sas_addr), phy_id,
1998 		SAS_ADDR(phy->attached_sas_addr));
1999 	sas_unregister_devs_sas_addr(dev, phy_id, last);
2000 
2001 	return sas_discover_new(dev, phy_id);
2002 }
2003 
2004 /**
2005  * sas_rediscover - revalidate the domain.
2006  * @dev:domain device to be detect.
2007  * @phy_id: the phy id will be detected.
2008  *
2009  * NOTE: this process _must_ quit (return) as soon as any connection
2010  * errors are encountered.  Connection recovery is done elsewhere.
2011  * Discover process only interrogates devices in order to discover the
2012  * domain.For plugging out, we un-register the device only when it is
2013  * the last phy in the port, for other phys in this port, we just delete it
2014  * from the port.For inserting, we do discovery when it is the
2015  * first phy,for other phys in this port, we add it to the port to
2016  * forming the wide-port.
2017  */
2018 static int sas_rediscover(struct domain_device *dev, const int phy_id)
2019 {
2020 	struct expander_device *ex = &dev->ex_dev;
2021 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
2022 	int res = 0;
2023 	int i;
2024 	bool last = true;	/* is this the last phy of the port */
2025 
2026 	pr_debug("ex %016llx phy%02d originated BROADCAST(CHANGE)\n",
2027 		 SAS_ADDR(dev->sas_addr), phy_id);
2028 
2029 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
2030 		for (i = 0; i < ex->num_phys; i++) {
2031 			struct ex_phy *phy = &ex->ex_phy[i];
2032 
2033 			if (i == phy_id)
2034 				continue;
2035 			if (sas_phy_addr_match(phy, changed_phy)) {
2036 				last = false;
2037 				break;
2038 			}
2039 		}
2040 		res = sas_rediscover_dev(dev, phy_id, last, i);
2041 	} else
2042 		res = sas_discover_new(dev, phy_id);
2043 	return res;
2044 }
2045 
2046 /**
2047  * sas_ex_revalidate_domain - revalidate the domain
2048  * @port_dev: port domain device.
2049  *
2050  * NOTE: this process _must_ quit (return) as soon as any connection
2051  * errors are encountered.  Connection recovery is done elsewhere.
2052  * Discover process only interrogates devices in order to discover the
2053  * domain.
2054  */
2055 int sas_ex_revalidate_domain(struct domain_device *port_dev)
2056 {
2057 	int res;
2058 	struct domain_device *dev = NULL;
2059 
2060 	res = sas_find_bcast_dev(port_dev, &dev);
2061 	if (res == 0 && dev) {
2062 		struct expander_device *ex = &dev->ex_dev;
2063 		int i = 0, phy_id;
2064 
2065 		do {
2066 			phy_id = -1;
2067 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
2068 			if (phy_id == -1)
2069 				break;
2070 			res = sas_rediscover(dev, phy_id);
2071 			i = phy_id + 1;
2072 		} while (i < ex->num_phys);
2073 	}
2074 	return res;
2075 }
2076 
2077 int sas_find_attached_phy_id(struct expander_device *ex_dev,
2078 			     struct domain_device *dev)
2079 {
2080 	struct ex_phy *phy;
2081 	int phy_id;
2082 
2083 	for (phy_id = 0; phy_id < ex_dev->num_phys; phy_id++) {
2084 		phy = &ex_dev->ex_phy[phy_id];
2085 		if (sas_phy_match_dev_addr(dev, phy))
2086 			return phy_id;
2087 	}
2088 
2089 	return -ENODEV;
2090 }
2091 EXPORT_SYMBOL_GPL(sas_find_attached_phy_id);
2092 
2093 void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
2094 		struct sas_rphy *rphy)
2095 {
2096 	struct domain_device *dev;
2097 	unsigned int rcvlen = 0;
2098 	int ret = -EINVAL;
2099 
2100 	/* no rphy means no smp target support (ie aic94xx host) */
2101 	if (!rphy)
2102 		return sas_smp_host_handler(job, shost);
2103 
2104 	switch (rphy->identify.device_type) {
2105 	case SAS_EDGE_EXPANDER_DEVICE:
2106 	case SAS_FANOUT_EXPANDER_DEVICE:
2107 		break;
2108 	default:
2109 		pr_err("%s: can we send a smp request to a device?\n",
2110 		       __func__);
2111 		goto out;
2112 	}
2113 
2114 	dev = sas_find_dev_by_rphy(rphy);
2115 	if (!dev) {
2116 		pr_err("%s: fail to find a domain_device?\n", __func__);
2117 		goto out;
2118 	}
2119 
2120 	/* do we need to support multiple segments? */
2121 	if (job->request_payload.sg_cnt > 1 ||
2122 	    job->reply_payload.sg_cnt > 1) {
2123 		pr_info("%s: multiple segments req %u, rsp %u\n",
2124 			__func__, job->request_payload.payload_len,
2125 			job->reply_payload.payload_len);
2126 		goto out;
2127 	}
2128 
2129 	ret = smp_execute_task_sg(dev, job->request_payload.sg_list,
2130 			job->reply_payload.sg_list);
2131 	if (ret >= 0) {
2132 		/* bsg_job_done() requires the length received  */
2133 		rcvlen = job->reply_payload.payload_len - ret;
2134 		ret = 0;
2135 	}
2136 
2137 out:
2138 	bsg_job_done(job, ret, rcvlen);
2139 }
2140