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