xref: /linux/drivers/scsi/libsas/sas_expander.c (revision 81e097a064b28b4a1f6ca1a8b433e659c1bd64c0)
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 <linux/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 static void sas_port_add_ex_phy(struct sas_port *port, struct ex_phy *ex_phy)
30 {
31 	sas_port_add_phy(port, ex_phy->phy);
32 	ex_phy->port = port;
33 	ex_phy->phy_state = PHY_DEVICE_DISCOVERED;
34 }
35 
36 static void sas_ex_add_parent_port(struct domain_device *dev, int phy_id)
37 {
38 	struct expander_device *ex = &dev->ex_dev;
39 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
40 
41 	if (!ex->parent_port) {
42 		ex->parent_port = sas_port_alloc(&dev->rphy->dev, phy_id);
43 		/* FIXME: error handling */
44 		BUG_ON(!ex->parent_port);
45 		BUG_ON(sas_port_add(ex->parent_port));
46 		sas_port_mark_backlink(ex->parent_port);
47 	}
48 	sas_port_add_ex_phy(ex->parent_port, ex_phy);
49 }
50 
51 /* ---------- SMP task management ---------- */
52 
53 /* Give it some long enough timeout. In seconds. */
54 #define SMP_TIMEOUT 10
55 
56 static int smp_execute_task_sg(struct domain_device *dev,
57 		struct scatterlist *req, struct scatterlist *resp)
58 {
59 	int res, retry;
60 	struct sas_task *task = NULL;
61 	struct sas_internal *i =
62 		to_sas_internal(dev->port->ha->shost->transportt);
63 	struct sas_ha_struct *ha = dev->port->ha;
64 
65 	/*
66 	 * Non-blocking: a sync resume here would deadlock against
67 	 * sas_drain_work() during HA resume.
68 	 */
69 	pm_runtime_get_noresume(ha->dev);
70 	mutex_lock(&dev->ex_dev.cmd_mutex);
71 	for (retry = 0; retry < 3; retry++) {
72 		if (test_bit(SAS_DEV_GONE, &dev->state)) {
73 			res = -ECOMM;
74 			break;
75 		}
76 
77 		task = sas_alloc_slow_task(GFP_KERNEL);
78 		if (!task) {
79 			res = -ENOMEM;
80 			break;
81 		}
82 		task->dev = dev;
83 		task->task_proto = dev->tproto;
84 		task->smp_task.smp_req = *req;
85 		task->smp_task.smp_resp = *resp;
86 
87 		task->task_done = sas_task_internal_done;
88 
89 		task->slow_task->timer.function = sas_task_internal_timedout;
90 		task->slow_task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
91 		add_timer(&task->slow_task->timer);
92 
93 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
94 
95 		if (res) {
96 			timer_delete_sync(&task->slow_task->timer);
97 			pr_notice("executing SMP task failed:%d\n", res);
98 			break;
99 		}
100 
101 		wait_for_completion(&task->slow_task->completion);
102 		res = -ECOMM;
103 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
104 			pr_notice("smp task timed out or aborted\n");
105 			i->dft->lldd_abort_task(task);
106 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
107 				pr_notice("SMP task aborted and not done\n");
108 				break;
109 			}
110 		}
111 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
112 		    task->task_status.stat == SAS_SAM_STAT_GOOD) {
113 			res = 0;
114 			break;
115 		}
116 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
117 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
118 			/* no error, but return the number of bytes of
119 			 * underrun */
120 			res = task->task_status.residual;
121 			break;
122 		}
123 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
124 		    task->task_status.stat == SAS_DATA_OVERRUN) {
125 			res = -EMSGSIZE;
126 			break;
127 		}
128 		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
129 		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
130 			break;
131 		else {
132 			pr_notice("%s: task to dev %016llx response: 0x%x status 0x%x\n",
133 				  __func__,
134 				  SAS_ADDR(dev->sas_addr),
135 				  task->task_status.resp,
136 				  task->task_status.stat);
137 			sas_free_task(task);
138 			task = NULL;
139 		}
140 	}
141 	mutex_unlock(&dev->ex_dev.cmd_mutex);
142 	pm_runtime_put(ha->dev);
143 
144 	BUG_ON(retry == 3 && task != NULL);
145 	sas_free_task(task);
146 	return res;
147 }
148 
149 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
150 			    void *resp, int resp_size)
151 {
152 	struct scatterlist req_sg;
153 	struct scatterlist resp_sg;
154 
155 	sg_init_one(&req_sg, req, req_size);
156 	sg_init_one(&resp_sg, resp, resp_size);
157 	return smp_execute_task_sg(dev, &req_sg, &resp_sg);
158 }
159 
160 /* ---------- Allocations ---------- */
161 
162 static inline void *alloc_smp_req(int size)
163 {
164 	u8 *p = kzalloc(ALIGN(size, ARCH_DMA_MINALIGN), GFP_KERNEL);
165 	if (p)
166 		p[0] = SMP_REQUEST;
167 	return p;
168 }
169 
170 static inline void *alloc_smp_resp(int size)
171 {
172 	return kzalloc(size, GFP_KERNEL);
173 }
174 
175 static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
176 {
177 	switch (phy->routing_attr) {
178 	case TABLE_ROUTING:
179 		if (dev->ex_dev.t2t_supp)
180 			return 'U';
181 		else
182 			return 'T';
183 	case DIRECT_ROUTING:
184 		return 'D';
185 	case SUBTRACTIVE_ROUTING:
186 		return 'S';
187 	default:
188 		return '?';
189 	}
190 }
191 
192 static enum sas_device_type to_dev_type(struct discover_resp *dr)
193 {
194 	/* This is detecting a failure to transmit initial dev to host
195 	 * FIS as described in section J.5 of sas-2 r16
196 	 */
197 	if (dr->attached_dev_type == SAS_PHY_UNUSED && dr->attached_sata_dev &&
198 	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
199 		return SAS_SATA_PENDING;
200 	else
201 		return dr->attached_dev_type;
202 }
203 
204 static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
205 			   struct smp_disc_resp *disc_resp)
206 {
207 	enum sas_device_type dev_type;
208 	enum sas_linkrate linkrate;
209 	u8 sas_addr[SAS_ADDR_SIZE];
210 	struct discover_resp *dr = &disc_resp->disc;
211 	struct sas_ha_struct *ha = dev->port->ha;
212 	struct expander_device *ex = &dev->ex_dev;
213 	struct ex_phy *phy = &ex->ex_phy[phy_id];
214 	struct sas_rphy *rphy = dev->rphy;
215 	bool new_phy = !phy->phy;
216 	char *type;
217 
218 	if (new_phy) {
219 		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
220 			return;
221 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
222 
223 		/* FIXME: error_handling */
224 		BUG_ON(!phy->phy);
225 	}
226 
227 	switch (disc_resp->result) {
228 	case SMP_RESP_PHY_VACANT:
229 		phy->phy_state = PHY_VACANT;
230 		break;
231 	default:
232 		phy->phy_state = PHY_NOT_PRESENT;
233 		break;
234 	case SMP_RESP_FUNC_ACC:
235 		phy->phy_state = PHY_EMPTY; /* do not know yet */
236 		break;
237 	}
238 
239 	/* check if anything important changed to squelch debug */
240 	dev_type = phy->attached_dev_type;
241 	linkrate  = phy->linkrate;
242 	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
243 
244 	/* Handle vacant phy - rest of dr data is not valid so skip it */
245 	if (phy->phy_state == PHY_VACANT) {
246 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
247 		phy->attached_dev_type = SAS_PHY_UNUSED;
248 		if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
249 			phy->phy_id = phy_id;
250 			goto skip;
251 		} else
252 			goto out;
253 	}
254 
255 	phy->attached_dev_type = to_dev_type(dr);
256 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
257 		goto out;
258 	phy->phy_id = phy_id;
259 	phy->linkrate = dr->linkrate;
260 	phy->attached_sata_host = dr->attached_sata_host;
261 	phy->attached_sata_dev  = dr->attached_sata_dev;
262 	phy->attached_sata_ps   = dr->attached_sata_ps;
263 	phy->attached_iproto = dr->iproto << 1;
264 	phy->attached_tproto = dr->tproto << 1;
265 	/* help some expanders that fail to zero sas_address in the 'no
266 	 * device' case
267 	 */
268 	if (phy->attached_dev_type == SAS_PHY_UNUSED)
269 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
270 	else
271 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
272 	phy->attached_phy_id = dr->attached_phy_id;
273 	phy->phy_change_count = dr->change_count;
274 	phy->routing_attr = dr->routing_attr;
275 	phy->virtual = dr->virtual;
276 	phy->last_da_index = -1;
277 
278 	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
279 	phy->phy->identify.device_type = dr->attached_dev_type;
280 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
281 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
282 	if (!phy->attached_tproto && dr->attached_sata_dev)
283 		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
284 	phy->phy->identify.phy_identifier = phy_id;
285 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
286 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
287 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
288 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
289 	phy->phy->negotiated_linkrate = phy->linkrate;
290 	phy->phy->enabled = (phy->linkrate != SAS_PHY_DISABLED);
291 
292  skip:
293 	if (new_phy)
294 		if (sas_phy_add(phy->phy)) {
295 			sas_phy_free(phy->phy);
296 			return;
297 		}
298 
299  out:
300 	switch (phy->attached_dev_type) {
301 	case SAS_SATA_PENDING:
302 		type = "stp pending";
303 		break;
304 	case SAS_PHY_UNUSED:
305 		type = "no device";
306 		break;
307 	case SAS_END_DEVICE:
308 		if (phy->attached_iproto) {
309 			if (phy->attached_tproto)
310 				type = "host+target";
311 			else
312 				type = "host";
313 		} else {
314 			if (dr->attached_sata_dev)
315 				type = "stp";
316 			else
317 				type = "ssp";
318 		}
319 		break;
320 	case SAS_EDGE_EXPANDER_DEVICE:
321 	case SAS_FANOUT_EXPANDER_DEVICE:
322 		type = "smp";
323 		break;
324 	default:
325 		type = "unknown";
326 	}
327 
328 	/* this routine is polled by libata error recovery so filter
329 	 * unimportant messages
330 	 */
331 	if (new_phy || phy->attached_dev_type != dev_type ||
332 	    phy->linkrate != linkrate ||
333 	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
334 		/* pass */;
335 	else
336 		return;
337 
338 	/* if the attached device type changed and ata_eh is active,
339 	 * make sure we run revalidation when eh completes (see:
340 	 * sas_enable_revalidation)
341 	 */
342 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
343 		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
344 
345 	pr_debug("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
346 		 test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
347 		 SAS_ADDR(dev->sas_addr), phy->phy_id,
348 		 sas_route_char(dev, phy), phy->linkrate,
349 		 SAS_ADDR(phy->attached_sas_addr), type);
350 }
351 
352 /* Return the domain device attached to an expander phy */
353 struct domain_device *sas_ex_phy_to_dev(struct domain_device *ex_dev, int phy_id)
354 {
355 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
356 	struct sas_rphy *rphy;
357 
358 	if (!ex_phy->port)
359 		return NULL;
360 
361 	rphy = ex_phy->port->rphy;
362 	if (!rphy)
363 		return NULL;
364 
365 	return sas_find_dev_by_rphy(rphy);
366 }
367 
368 /* Check if we have an existing attached ata device on this expander phy */
369 struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
370 {
371 	struct domain_device *dev = sas_ex_phy_to_dev(ex_dev, phy_id);
372 
373 	if (dev && dev_is_sata(dev))
374 		return dev;
375 
376 	return NULL;
377 }
378 
379 #define DISCOVER_REQ_SIZE  16
380 #define DISCOVER_RESP_SIZE sizeof(struct smp_disc_resp)
381 
382 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
383 				      struct smp_disc_resp *disc_resp,
384 				      int single)
385 {
386 	struct discover_resp *dr = &disc_resp->disc;
387 	int res;
388 
389 	disc_req[9] = single;
390 
391 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
392 			       disc_resp, DISCOVER_RESP_SIZE);
393 	if (res)
394 		return res;
395 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
396 		pr_notice("Found loopback topology, just ignore it!\n");
397 		return 0;
398 	}
399 	sas_set_ex_phy(dev, single, disc_resp);
400 	return 0;
401 }
402 
403 int sas_ex_phy_discover(struct domain_device *dev, int single)
404 {
405 	struct expander_device *ex = &dev->ex_dev;
406 	int  res = 0;
407 	u8   *disc_req;
408 	struct smp_disc_resp *disc_resp;
409 
410 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
411 	if (!disc_req)
412 		return -ENOMEM;
413 
414 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
415 	if (!disc_resp) {
416 		kfree(disc_req);
417 		return -ENOMEM;
418 	}
419 
420 	disc_req[1] = SMP_DISCOVER;
421 
422 	if (0 <= single && single < ex->num_phys) {
423 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
424 	} else {
425 		int i;
426 
427 		for (i = 0; i < ex->num_phys; i++) {
428 			res = sas_ex_phy_discover_helper(dev, disc_req,
429 							 disc_resp, i);
430 			if (res)
431 				goto out_err;
432 		}
433 	}
434 out_err:
435 	kfree(disc_resp);
436 	kfree(disc_req);
437 	return res;
438 }
439 
440 static int sas_expander_discover(struct domain_device *dev)
441 {
442 	struct expander_device *ex = &dev->ex_dev;
443 	int res;
444 
445 	ex->ex_phy = kzalloc_objs(*ex->ex_phy, ex->num_phys);
446 	if (!ex->ex_phy)
447 		return -ENOMEM;
448 
449 	res = sas_ex_phy_discover(dev, -1);
450 	if (res)
451 		goto out_err;
452 
453 	return 0;
454  out_err:
455 	kfree(ex->ex_phy);
456 	ex->ex_phy = NULL;
457 	return res;
458 }
459 
460 #define MAX_EXPANDER_PHYS 128
461 
462 #define RG_REQ_SIZE   8
463 #define RG_RESP_SIZE  sizeof(struct smp_rg_resp)
464 
465 static int sas_ex_general(struct domain_device *dev)
466 {
467 	u8 *rg_req;
468 	struct smp_rg_resp *rg_resp;
469 	struct report_general_resp *rg;
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 		rg = &rg_resp->rg;
501 		dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
502 		dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
503 		dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
504 		dev->ex_dev.t2t_supp = rg->t2t_supp;
505 		dev->ex_dev.conf_route_table = rg->conf_route_table;
506 		dev->ex_dev.configuring = rg->configuring;
507 		memcpy(dev->ex_dev.enclosure_logical_id,
508 		       rg->enclosure_logical_id, 8);
509 
510 		if (dev->ex_dev.configuring) {
511 			pr_debug("RG: ex %016llx self-configuring...\n",
512 				 SAS_ADDR(dev->sas_addr));
513 			schedule_timeout_interruptible(5*HZ);
514 		} else
515 			break;
516 	}
517 out:
518 	kfree(rg_req);
519 	kfree(rg_resp);
520 	return res;
521 }
522 
523 static void ex_assign_manuf_info(struct domain_device *dev, void
524 					*_mi_resp)
525 {
526 	u8 *mi_resp = _mi_resp;
527 	struct sas_rphy *rphy = dev->rphy;
528 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
529 
530 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
531 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
532 	memcpy(edev->product_rev, mi_resp + 36,
533 	       SAS_EXPANDER_PRODUCT_REV_LEN);
534 
535 	if (mi_resp[8] & 1) {
536 		memcpy(edev->component_vendor_id, mi_resp + 40,
537 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
538 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
539 		edev->component_revision_id = mi_resp[50];
540 	}
541 }
542 
543 #define MI_REQ_SIZE   8
544 #define MI_RESP_SIZE 64
545 
546 static int sas_ex_manuf_info(struct domain_device *dev)
547 {
548 	u8 *mi_req;
549 	u8 *mi_resp;
550 	int res;
551 
552 	mi_req = alloc_smp_req(MI_REQ_SIZE);
553 	if (!mi_req)
554 		return -ENOMEM;
555 
556 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
557 	if (!mi_resp) {
558 		kfree(mi_req);
559 		return -ENOMEM;
560 	}
561 
562 	mi_req[1] = SMP_REPORT_MANUF_INFO;
563 
564 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp, MI_RESP_SIZE);
565 	if (res) {
566 		pr_notice("MI: ex %016llx failed:0x%x\n",
567 			  SAS_ADDR(dev->sas_addr), res);
568 		goto out;
569 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
570 		pr_debug("MI ex %016llx returned SMP result:0x%x\n",
571 			 SAS_ADDR(dev->sas_addr), mi_resp[2]);
572 		goto out;
573 	}
574 
575 	ex_assign_manuf_info(dev, mi_resp);
576 out:
577 	kfree(mi_req);
578 	kfree(mi_resp);
579 	return res;
580 }
581 
582 #define PC_REQ_SIZE  44
583 #define PC_RESP_SIZE 8
584 
585 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
586 			enum phy_func phy_func,
587 			struct sas_phy_linkrates *rates)
588 {
589 	u8 *pc_req;
590 	u8 *pc_resp;
591 	int res;
592 
593 	pc_req = alloc_smp_req(PC_REQ_SIZE);
594 	if (!pc_req)
595 		return -ENOMEM;
596 
597 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
598 	if (!pc_resp) {
599 		kfree(pc_req);
600 		return -ENOMEM;
601 	}
602 
603 	pc_req[1] = SMP_PHY_CONTROL;
604 	pc_req[9] = phy_id;
605 	pc_req[10] = phy_func;
606 	if (rates) {
607 		pc_req[32] = rates->minimum_linkrate << 4;
608 		pc_req[33] = rates->maximum_linkrate << 4;
609 	}
610 
611 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp, PC_RESP_SIZE);
612 	if (res) {
613 		pr_err("ex %016llx phy%02d PHY control failed: %d\n",
614 		       SAS_ADDR(dev->sas_addr), phy_id, res);
615 	} else if (pc_resp[2] != SMP_RESP_FUNC_ACC) {
616 		pr_err("ex %016llx phy%02d PHY control failed: function result 0x%x\n",
617 		       SAS_ADDR(dev->sas_addr), phy_id, pc_resp[2]);
618 		res = pc_resp[2];
619 	}
620 	kfree(pc_resp);
621 	kfree(pc_req);
622 	return res;
623 }
624 
625 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
626 {
627 	struct expander_device *ex = &dev->ex_dev;
628 	struct ex_phy *phy = &ex->ex_phy[phy_id];
629 
630 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
631 	phy->linkrate = SAS_PHY_DISABLED;
632 }
633 
634 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
635 {
636 	struct expander_device *ex = &dev->ex_dev;
637 	int i;
638 
639 	for (i = 0; i < ex->num_phys; i++) {
640 		struct ex_phy *phy = &ex->ex_phy[i];
641 
642 		if (phy->phy_state == PHY_VACANT ||
643 		    phy->phy_state == PHY_NOT_PRESENT)
644 			continue;
645 
646 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
647 			sas_ex_disable_phy(dev, i);
648 	}
649 }
650 
651 static int sas_dev_present_in_domain(struct asd_sas_port *port,
652 					    u8 *sas_addr)
653 {
654 	struct domain_device *dev;
655 
656 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
657 		return 1;
658 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
659 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
660 			return 1;
661 	}
662 	return 0;
663 }
664 
665 #define RPEL_REQ_SIZE	16
666 #define RPEL_RESP_SIZE	32
667 int sas_smp_get_phy_events(struct sas_phy *phy)
668 {
669 	int res;
670 	u8 *req;
671 	u8 *resp;
672 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
673 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
674 
675 	req = alloc_smp_req(RPEL_REQ_SIZE);
676 	if (!req)
677 		return -ENOMEM;
678 
679 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
680 	if (!resp) {
681 		kfree(req);
682 		return -ENOMEM;
683 	}
684 
685 	req[1] = SMP_REPORT_PHY_ERR_LOG;
686 	req[9] = phy->number;
687 
688 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
689 			       resp, RPEL_RESP_SIZE);
690 
691 	if (res)
692 		goto out;
693 
694 	phy->invalid_dword_count = get_unaligned_be32(&resp[12]);
695 	phy->running_disparity_error_count = get_unaligned_be32(&resp[16]);
696 	phy->loss_of_dword_sync_count = get_unaligned_be32(&resp[20]);
697 	phy->phy_reset_problem_count = get_unaligned_be32(&resp[24]);
698 
699  out:
700 	kfree(req);
701 	kfree(resp);
702 	return res;
703 
704 }
705 
706 #ifdef CONFIG_SCSI_SAS_ATA
707 
708 #define RPS_REQ_SIZE  16
709 #define RPS_RESP_SIZE sizeof(struct smp_rps_resp)
710 
711 int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
712 			    struct smp_rps_resp *rps_resp)
713 {
714 	int res;
715 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
716 	u8 *resp = (u8 *)rps_resp;
717 
718 	if (!rps_req)
719 		return -ENOMEM;
720 
721 	rps_req[1] = SMP_REPORT_PHY_SATA;
722 	rps_req[9] = phy_id;
723 
724 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
725 			       rps_resp, RPS_RESP_SIZE);
726 
727 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
728 	 * standards cockup here.  sas-2 explicitly specifies the FIS
729 	 * should be encoded so that FIS type is in resp[24].
730 	 * However, some expanders endian reverse this.  Undo the
731 	 * reversal here */
732 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
733 		int i;
734 
735 		for (i = 0; i < 5; i++) {
736 			int j = 24 + (i*4);
737 			u8 a, b;
738 			a = resp[j + 0];
739 			b = resp[j + 1];
740 			resp[j + 0] = resp[j + 3];
741 			resp[j + 1] = resp[j + 2];
742 			resp[j + 2] = b;
743 			resp[j + 3] = a;
744 		}
745 	}
746 
747 	kfree(rps_req);
748 	return res;
749 }
750 #endif
751 
752 static void sas_ex_get_linkrate(struct domain_device *parent,
753 				       struct domain_device *child,
754 				       struct ex_phy *parent_phy)
755 {
756 	struct expander_device *parent_ex = &parent->ex_dev;
757 	struct sas_port *port;
758 	int i;
759 
760 	child->pathways = 0;
761 
762 	port = parent_phy->port;
763 
764 	for (i = 0; i < parent_ex->num_phys; i++) {
765 		struct ex_phy *phy = &parent_ex->ex_phy[i];
766 
767 		if (phy->phy_state == PHY_VACANT ||
768 		    phy->phy_state == PHY_NOT_PRESENT)
769 			continue;
770 
771 		if (sas_phy_match_dev_addr(child, phy)) {
772 			child->min_linkrate = min(parent->min_linkrate,
773 						  phy->linkrate);
774 			child->max_linkrate = max(parent->max_linkrate,
775 						  phy->linkrate);
776 			child->pathways++;
777 			sas_port_add_phy(port, phy->phy);
778 		}
779 	}
780 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
781 	child->pathways = min(child->pathways, parent->pathways);
782 }
783 
784 static int sas_ex_add_dev(struct domain_device *parent, struct ex_phy *phy,
785 			  struct domain_device *child, int phy_id)
786 {
787 	struct sas_rphy *rphy;
788 	int res;
789 
790 	child->dev_type = SAS_END_DEVICE;
791 	rphy = sas_end_device_alloc(phy->port);
792 	if (!rphy)
793 		return -ENOMEM;
794 
795 	child->tproto = phy->attached_tproto;
796 	sas_init_dev(child);
797 
798 	child->rphy = rphy;
799 	get_device(&rphy->dev);
800 	rphy->identify.phy_identifier = phy_id;
801 	sas_fill_in_rphy(child, rphy);
802 
803 	list_add_tail(&child->disco_list_node, &parent->port->disco_list);
804 
805 	res = sas_notify_lldd_dev_found(child);
806 	if (res) {
807 		pr_notice("notify lldd for device %016llx at %016llx:%02d returned 0x%x\n",
808 			  SAS_ADDR(child->sas_addr),
809 			  SAS_ADDR(parent->sas_addr), phy_id, res);
810 		sas_rphy_free(child->rphy);
811 		list_del(&child->disco_list_node);
812 		return res;
813 	}
814 
815 	return 0;
816 }
817 
818 static struct domain_device *sas_ex_discover_end_dev(
819 	struct domain_device *parent, int phy_id)
820 {
821 	struct expander_device *parent_ex = &parent->ex_dev;
822 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
823 	struct domain_device *child = NULL;
824 	int res;
825 
826 	if (phy->attached_sata_host || phy->attached_sata_ps)
827 		return NULL;
828 
829 	child = sas_alloc_device();
830 	if (!child)
831 		return NULL;
832 
833 	kref_get(&parent->kref);
834 	child->parent = parent;
835 	child->port   = parent->port;
836 	child->iproto = phy->attached_iproto;
837 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
838 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
839 	if (!phy->port) {
840 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
841 		if (unlikely(!phy->port))
842 			goto out_err;
843 		if (unlikely(sas_port_add(phy->port) != 0)) {
844 			sas_port_free(phy->port);
845 			goto out_err;
846 		}
847 	}
848 	sas_ex_get_linkrate(parent, child, phy);
849 	sas_device_set_phy(child, phy->port);
850 
851 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
852 		res = sas_ata_add_dev(parent, phy, child, phy_id);
853 	} else if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
854 		res = sas_ex_add_dev(parent, phy, child, phy_id);
855 	} else {
856 		pr_notice("target proto 0x%x at %016llx:0x%x not handled\n",
857 			  phy->attached_tproto, SAS_ADDR(parent->sas_addr),
858 			  phy_id);
859 		res = -ENODEV;
860 	}
861 
862 	if (res)
863 		goto out_free;
864 
865 	list_add_tail(&child->siblings, &parent_ex->children);
866 	return child;
867 
868  out_free:
869 	sas_port_delete(phy->port);
870  out_err:
871 	phy->port = NULL;
872 	sas_put_device(child);
873 	return NULL;
874 }
875 
876 /* See if this phy is part of a wide port */
877 static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
878 {
879 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
880 	int i;
881 
882 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
883 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
884 
885 		if (ephy == phy)
886 			continue;
887 
888 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
889 			    SAS_ADDR_SIZE) && ephy->port) {
890 			sas_port_add_ex_phy(ephy->port, phy);
891 			return true;
892 		}
893 	}
894 
895 	return false;
896 }
897 
898 static struct domain_device *sas_ex_discover_expander(
899 	struct domain_device *parent, int phy_id)
900 {
901 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
902 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
903 	struct domain_device *child = NULL;
904 	struct sas_rphy *rphy;
905 	struct sas_expander_device *edev;
906 	struct asd_sas_port *port;
907 	int res;
908 
909 	if (phy->routing_attr == DIRECT_ROUTING) {
910 		pr_warn("ex %016llx:%02d:D <--> ex %016llx:0x%x is not allowed\n",
911 			SAS_ADDR(parent->sas_addr), phy_id,
912 			SAS_ADDR(phy->attached_sas_addr),
913 			phy->attached_phy_id);
914 		return NULL;
915 	}
916 	child = sas_alloc_device();
917 	if (!child)
918 		return NULL;
919 
920 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
921 	/* FIXME: better error handling */
922 	BUG_ON(sas_port_add(phy->port) != 0);
923 
924 
925 	switch (phy->attached_dev_type) {
926 	case SAS_EDGE_EXPANDER_DEVICE:
927 		rphy = sas_expander_alloc(phy->port,
928 					  SAS_EDGE_EXPANDER_DEVICE);
929 		break;
930 	case SAS_FANOUT_EXPANDER_DEVICE:
931 		rphy = sas_expander_alloc(phy->port,
932 					  SAS_FANOUT_EXPANDER_DEVICE);
933 		break;
934 	default:
935 		rphy = NULL;	/* shut gcc up */
936 		BUG();
937 	}
938 	port = parent->port;
939 	child->rphy = rphy;
940 	get_device(&rphy->dev);
941 	edev = rphy_to_expander_device(rphy);
942 	child->dev_type = phy->attached_dev_type;
943 	kref_get(&parent->kref);
944 	child->parent = parent;
945 	child->port = port;
946 	child->iproto = phy->attached_iproto;
947 	child->tproto = phy->attached_tproto;
948 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
949 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
950 	sas_ex_get_linkrate(parent, child, phy);
951 	edev->level = parent_ex->level + 1;
952 	parent->port->disc.max_level = max(parent->port->disc.max_level,
953 					   edev->level);
954 	sas_init_dev(child);
955 	sas_fill_in_rphy(child, rphy);
956 	sas_rphy_add(rphy);
957 
958 	spin_lock_irq(&parent->port->dev_list_lock);
959 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
960 	spin_unlock_irq(&parent->port->dev_list_lock);
961 
962 	res = sas_discover_expander(child);
963 	if (res) {
964 		sas_rphy_delete(rphy);
965 		spin_lock_irq(&parent->port->dev_list_lock);
966 		list_del(&child->dev_list_node);
967 		spin_unlock_irq(&parent->port->dev_list_lock);
968 		sas_put_device(child);
969 		sas_port_delete(phy->port);
970 		phy->port = NULL;
971 		return NULL;
972 	}
973 	list_add_tail(&child->siblings, &parent->ex_dev.children);
974 	return child;
975 }
976 
977 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
978 {
979 	struct expander_device *ex = &dev->ex_dev;
980 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
981 	struct domain_device *child = NULL;
982 	int res = 0;
983 
984 	/* Phy state */
985 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
986 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
987 			res = sas_ex_phy_discover(dev, phy_id);
988 		if (res)
989 			return res;
990 	}
991 
992 	/* Parent and domain coherency */
993 	if (!dev->parent && sas_phy_match_port_addr(dev->port, ex_phy)) {
994 		sas_ex_add_parent_port(dev, phy_id);
995 		return 0;
996 	}
997 	if (dev->parent && sas_phy_match_dev_addr(dev->parent, ex_phy)) {
998 		sas_ex_add_parent_port(dev, phy_id);
999 		if (ex_phy->routing_attr == TABLE_ROUTING)
1000 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
1001 		return 0;
1002 	}
1003 
1004 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
1005 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
1006 
1007 	if (ex_phy->attached_dev_type == SAS_PHY_UNUSED) {
1008 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
1009 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1010 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
1011 		}
1012 		return 0;
1013 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
1014 		return 0;
1015 
1016 	if (ex_phy->attached_dev_type != SAS_END_DEVICE &&
1017 	    ex_phy->attached_dev_type != SAS_FANOUT_EXPANDER_DEVICE &&
1018 	    ex_phy->attached_dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1019 	    ex_phy->attached_dev_type != SAS_SATA_PENDING) {
1020 		pr_warn("unknown device type(0x%x) attached to ex %016llx phy%02d\n",
1021 			ex_phy->attached_dev_type,
1022 			SAS_ADDR(dev->sas_addr),
1023 			phy_id);
1024 		return 0;
1025 	}
1026 
1027 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
1028 	if (res) {
1029 		pr_notice("configure routing for dev %016llx reported 0x%x. Forgotten\n",
1030 			  SAS_ADDR(ex_phy->attached_sas_addr), res);
1031 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
1032 		return res;
1033 	}
1034 
1035 	if (sas_ex_join_wide_port(dev, phy_id)) {
1036 		pr_debug("Attaching ex phy%02d to wide port %016llx\n",
1037 			 phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
1038 		return res;
1039 	}
1040 
1041 	switch (ex_phy->attached_dev_type) {
1042 	case SAS_END_DEVICE:
1043 	case SAS_SATA_PENDING:
1044 		child = sas_ex_discover_end_dev(dev, phy_id);
1045 		break;
1046 	case SAS_FANOUT_EXPANDER_DEVICE:
1047 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
1048 			pr_debug("second fanout expander %016llx phy%02d attached to ex %016llx phy%02d\n",
1049 				 SAS_ADDR(ex_phy->attached_sas_addr),
1050 				 ex_phy->attached_phy_id,
1051 				 SAS_ADDR(dev->sas_addr),
1052 				 phy_id);
1053 			sas_ex_disable_phy(dev, phy_id);
1054 			return res;
1055 		} else
1056 			memcpy(dev->port->disc.fanout_sas_addr,
1057 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
1058 		fallthrough;
1059 	case SAS_EDGE_EXPANDER_DEVICE:
1060 		child = sas_ex_discover_expander(dev, phy_id);
1061 		break;
1062 	default:
1063 		break;
1064 	}
1065 
1066 	if (!child)
1067 		pr_notice("ex %016llx phy%02d failed to discover\n",
1068 			  SAS_ADDR(dev->sas_addr), phy_id);
1069 	return res;
1070 }
1071 
1072 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
1073 {
1074 	struct expander_device *ex = &dev->ex_dev;
1075 	int i;
1076 
1077 	for (i = 0; i < ex->num_phys; i++) {
1078 		struct ex_phy *phy = &ex->ex_phy[i];
1079 
1080 		if (phy->phy_state == PHY_VACANT ||
1081 		    phy->phy_state == PHY_NOT_PRESENT)
1082 			continue;
1083 
1084 		if (dev_is_expander(phy->attached_dev_type) &&
1085 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1086 
1087 			memcpy(sub_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
1088 
1089 			return 1;
1090 		}
1091 	}
1092 	return 0;
1093 }
1094 
1095 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1096 {
1097 	struct expander_device *ex = &dev->ex_dev;
1098 	struct domain_device *child;
1099 	u8 sub_addr[SAS_ADDR_SIZE] = {0, };
1100 
1101 	list_for_each_entry(child, &ex->children, siblings) {
1102 		if (!dev_is_expander(child->dev_type))
1103 			continue;
1104 		if (sub_addr[0] == 0) {
1105 			sas_find_sub_addr(child, sub_addr);
1106 			continue;
1107 		} else {
1108 			u8 s2[SAS_ADDR_SIZE];
1109 
1110 			if (sas_find_sub_addr(child, s2) &&
1111 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1112 
1113 				pr_notice("ex %016llx->%016llx-?->%016llx diverges from subtractive boundary %016llx\n",
1114 					  SAS_ADDR(dev->sas_addr),
1115 					  SAS_ADDR(child->sas_addr),
1116 					  SAS_ADDR(s2),
1117 					  SAS_ADDR(sub_addr));
1118 
1119 				sas_ex_disable_port(child, s2);
1120 			}
1121 		}
1122 	}
1123 	return 0;
1124 }
1125 /**
1126  * sas_ex_discover_devices - discover devices attached to this expander
1127  * @dev: pointer to the expander domain device
1128  * @single: if you want to do a single phy, else set to -1;
1129  *
1130  * Configure this expander for use with its devices and register the
1131  * devices of this expander.
1132  */
1133 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1134 {
1135 	struct expander_device *ex = &dev->ex_dev;
1136 	int i = 0, end = ex->num_phys;
1137 	int res = 0;
1138 
1139 	if (0 <= single && single < end) {
1140 		i = single;
1141 		end = i+1;
1142 	}
1143 
1144 	for ( ; i < end; i++) {
1145 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1146 
1147 		if (ex_phy->phy_state == PHY_VACANT ||
1148 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1149 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1150 			continue;
1151 
1152 		switch (ex_phy->linkrate) {
1153 		case SAS_PHY_DISABLED:
1154 		case SAS_PHY_RESET_PROBLEM:
1155 		case SAS_SATA_PORT_SELECTOR:
1156 			continue;
1157 		default:
1158 			res = sas_ex_discover_dev(dev, i);
1159 			if (res)
1160 				break;
1161 			continue;
1162 		}
1163 	}
1164 
1165 	if (!res)
1166 		sas_check_level_subtractive_boundary(dev);
1167 
1168 	return res;
1169 }
1170 
1171 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1172 {
1173 	struct expander_device *ex = &dev->ex_dev;
1174 	int i;
1175 	u8  *sub_sas_addr = NULL;
1176 
1177 	if (dev->dev_type != SAS_EDGE_EXPANDER_DEVICE)
1178 		return 0;
1179 
1180 	for (i = 0; i < ex->num_phys; i++) {
1181 		struct ex_phy *phy = &ex->ex_phy[i];
1182 
1183 		if (phy->phy_state == PHY_VACANT ||
1184 		    phy->phy_state == PHY_NOT_PRESENT)
1185 			continue;
1186 
1187 		if (dev_is_expander(phy->attached_dev_type) &&
1188 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1189 
1190 			if (!sub_sas_addr)
1191 				sub_sas_addr = &phy->attached_sas_addr[0];
1192 			else if (SAS_ADDR(sub_sas_addr) !=
1193 				 SAS_ADDR(phy->attached_sas_addr)) {
1194 
1195 				pr_notice("ex %016llx phy%02d diverges(%016llx) on subtractive boundary(%016llx). Disabled\n",
1196 					  SAS_ADDR(dev->sas_addr), i,
1197 					  SAS_ADDR(phy->attached_sas_addr),
1198 					  SAS_ADDR(sub_sas_addr));
1199 				sas_ex_disable_phy(dev, i);
1200 			}
1201 		}
1202 	}
1203 	return 0;
1204 }
1205 
1206 static void sas_print_parent_topology_bug(struct domain_device *child,
1207 						 struct ex_phy *parent_phy,
1208 						 struct ex_phy *child_phy)
1209 {
1210 	static const char *ex_type[] = {
1211 		[SAS_EDGE_EXPANDER_DEVICE] = "edge",
1212 		[SAS_FANOUT_EXPANDER_DEVICE] = "fanout",
1213 	};
1214 	struct domain_device *parent = child->parent;
1215 
1216 	pr_notice("%s ex %016llx phy%02d <--> %s ex %016llx phy%02d has %c:%c routing link!\n",
1217 		  ex_type[parent->dev_type],
1218 		  SAS_ADDR(parent->sas_addr),
1219 		  parent_phy->phy_id,
1220 
1221 		  ex_type[child->dev_type],
1222 		  SAS_ADDR(child->sas_addr),
1223 		  child_phy->phy_id,
1224 
1225 		  sas_route_char(parent, parent_phy),
1226 		  sas_route_char(child, child_phy));
1227 }
1228 
1229 static bool sas_eeds_valid(struct domain_device *parent,
1230 			   struct domain_device *child)
1231 {
1232 	struct sas_discovery *disc = &parent->port->disc;
1233 
1234 	return (SAS_ADDR(disc->eeds_a) == SAS_ADDR(parent->sas_addr) ||
1235 		SAS_ADDR(disc->eeds_a) == SAS_ADDR(child->sas_addr)) &&
1236 	       (SAS_ADDR(disc->eeds_b) == SAS_ADDR(parent->sas_addr) ||
1237 		SAS_ADDR(disc->eeds_b) == SAS_ADDR(child->sas_addr));
1238 }
1239 
1240 static int sas_check_eeds(struct domain_device *child,
1241 			  struct ex_phy *parent_phy,
1242 			  struct ex_phy *child_phy)
1243 {
1244 	int res = 0;
1245 	struct domain_device *parent = child->parent;
1246 	struct sas_discovery *disc = &parent->port->disc;
1247 
1248 	if (SAS_ADDR(disc->fanout_sas_addr) != 0) {
1249 		res = -ENODEV;
1250 		pr_warn("edge ex %016llx phy S:%02d <--> edge ex %016llx phy S:%02d, while there is a fanout ex %016llx\n",
1251 			SAS_ADDR(parent->sas_addr),
1252 			parent_phy->phy_id,
1253 			SAS_ADDR(child->sas_addr),
1254 			child_phy->phy_id,
1255 			SAS_ADDR(disc->fanout_sas_addr));
1256 	} else if (SAS_ADDR(disc->eeds_a) == 0) {
1257 		memcpy(disc->eeds_a, parent->sas_addr, SAS_ADDR_SIZE);
1258 		memcpy(disc->eeds_b, child->sas_addr, SAS_ADDR_SIZE);
1259 	} else if (!sas_eeds_valid(parent, child)) {
1260 		res = -ENODEV;
1261 		pr_warn("edge ex %016llx phy%02d <--> edge ex %016llx phy%02d link forms a third EEDS!\n",
1262 			SAS_ADDR(parent->sas_addr),
1263 			parent_phy->phy_id,
1264 			SAS_ADDR(child->sas_addr),
1265 			child_phy->phy_id);
1266 	}
1267 
1268 	return res;
1269 }
1270 
1271 static int sas_check_edge_expander_topo(struct domain_device *child,
1272 					struct ex_phy *parent_phy)
1273 {
1274 	struct expander_device *child_ex = &child->ex_dev;
1275 	struct expander_device *parent_ex = &child->parent->ex_dev;
1276 	struct ex_phy *child_phy;
1277 
1278 	child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1279 
1280 	if (child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1281 		if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1282 		    child_phy->routing_attr != TABLE_ROUTING)
1283 			goto error;
1284 	} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1285 		if (child_phy->routing_attr == SUBTRACTIVE_ROUTING)
1286 			return sas_check_eeds(child, parent_phy, child_phy);
1287 		else if (child_phy->routing_attr != TABLE_ROUTING)
1288 			goto error;
1289 	} else if (parent_phy->routing_attr == TABLE_ROUTING) {
1290 		if (child_phy->routing_attr != SUBTRACTIVE_ROUTING &&
1291 		    (child_phy->routing_attr != TABLE_ROUTING ||
1292 		     !child_ex->t2t_supp || !parent_ex->t2t_supp))
1293 			goto error;
1294 	}
1295 
1296 	return 0;
1297 error:
1298 	sas_print_parent_topology_bug(child, parent_phy, child_phy);
1299 	return -ENODEV;
1300 }
1301 
1302 static int sas_check_fanout_expander_topo(struct domain_device *child,
1303 					  struct ex_phy *parent_phy)
1304 {
1305 	struct expander_device *child_ex = &child->ex_dev;
1306 	struct ex_phy *child_phy;
1307 
1308 	child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1309 
1310 	if (parent_phy->routing_attr == TABLE_ROUTING &&
1311 	    child_phy->routing_attr == SUBTRACTIVE_ROUTING)
1312 		return 0;
1313 
1314 	sas_print_parent_topology_bug(child, parent_phy, child_phy);
1315 
1316 	return -ENODEV;
1317 }
1318 
1319 static int sas_check_parent_topology(struct domain_device *child)
1320 {
1321 	struct expander_device *parent_ex;
1322 	int i;
1323 	int res = 0;
1324 
1325 	if (!dev_parent_is_expander(child))
1326 		return 0;
1327 
1328 	parent_ex = &child->parent->ex_dev;
1329 
1330 	for (i = 0; i < parent_ex->num_phys; i++) {
1331 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1332 
1333 		if (parent_phy->phy_state == PHY_VACANT ||
1334 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1335 			continue;
1336 
1337 		if (!sas_phy_match_dev_addr(child, parent_phy))
1338 			continue;
1339 
1340 		switch (child->parent->dev_type) {
1341 		case SAS_EDGE_EXPANDER_DEVICE:
1342 			if (sas_check_edge_expander_topo(child, parent_phy))
1343 				res = -ENODEV;
1344 			break;
1345 		case SAS_FANOUT_EXPANDER_DEVICE:
1346 			if (sas_check_fanout_expander_topo(child, parent_phy))
1347 				res = -ENODEV;
1348 			break;
1349 		default:
1350 			break;
1351 		}
1352 	}
1353 
1354 	return res;
1355 }
1356 
1357 #define RRI_REQ_SIZE  16
1358 #define RRI_RESP_SIZE 44
1359 
1360 static int sas_configure_present(struct domain_device *dev, int phy_id,
1361 				 u8 *sas_addr, int *index, int *present)
1362 {
1363 	int i, res = 0;
1364 	struct expander_device *ex = &dev->ex_dev;
1365 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1366 	u8 *rri_req;
1367 	u8 *rri_resp;
1368 
1369 	*present = 0;
1370 	*index = 0;
1371 
1372 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1373 	if (!rri_req)
1374 		return -ENOMEM;
1375 
1376 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1377 	if (!rri_resp) {
1378 		kfree(rri_req);
1379 		return -ENOMEM;
1380 	}
1381 
1382 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1383 	rri_req[9] = phy_id;
1384 
1385 	for (i = 0; i < ex->max_route_indexes ; i++) {
1386 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1387 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1388 				       RRI_RESP_SIZE);
1389 		if (res)
1390 			goto out;
1391 		res = rri_resp[2];
1392 		if (res == SMP_RESP_NO_INDEX) {
1393 			pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1394 				SAS_ADDR(dev->sas_addr), phy_id, i);
1395 			goto out;
1396 		} else if (res != SMP_RESP_FUNC_ACC) {
1397 			pr_notice("%s: dev %016llx phy%02d index 0x%x result 0x%x\n",
1398 				  __func__, SAS_ADDR(dev->sas_addr), phy_id,
1399 				  i, res);
1400 			goto out;
1401 		}
1402 		if (SAS_ADDR(sas_addr) != 0) {
1403 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1404 				*index = i;
1405 				if ((rri_resp[12] & 0x80) == 0x80)
1406 					*present = 0;
1407 				else
1408 					*present = 1;
1409 				goto out;
1410 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1411 				*index = i;
1412 				*present = 0;
1413 				goto out;
1414 			}
1415 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1416 			   phy->last_da_index < i) {
1417 			phy->last_da_index = i;
1418 			*index = i;
1419 			*present = 0;
1420 			goto out;
1421 		}
1422 	}
1423 	res = -1;
1424 out:
1425 	kfree(rri_req);
1426 	kfree(rri_resp);
1427 	return res;
1428 }
1429 
1430 #define CRI_REQ_SIZE  44
1431 #define CRI_RESP_SIZE  8
1432 
1433 static int sas_configure_set(struct domain_device *dev, int phy_id,
1434 			     u8 *sas_addr, int index, int include)
1435 {
1436 	int res;
1437 	u8 *cri_req;
1438 	u8 *cri_resp;
1439 
1440 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1441 	if (!cri_req)
1442 		return -ENOMEM;
1443 
1444 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1445 	if (!cri_resp) {
1446 		kfree(cri_req);
1447 		return -ENOMEM;
1448 	}
1449 
1450 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1451 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1452 	cri_req[9] = phy_id;
1453 	if (SAS_ADDR(sas_addr) == 0 || !include)
1454 		cri_req[12] |= 0x80;
1455 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1456 
1457 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1458 			       CRI_RESP_SIZE);
1459 	if (res)
1460 		goto out;
1461 	res = cri_resp[2];
1462 	if (res == SMP_RESP_NO_INDEX) {
1463 		pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
1464 			SAS_ADDR(dev->sas_addr), phy_id, index);
1465 	}
1466 out:
1467 	kfree(cri_req);
1468 	kfree(cri_resp);
1469 	return res;
1470 }
1471 
1472 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1473 				    u8 *sas_addr, int include)
1474 {
1475 	int index;
1476 	int present;
1477 	int res;
1478 
1479 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1480 	if (res)
1481 		return res;
1482 	if (include ^ present)
1483 		return sas_configure_set(dev, phy_id, sas_addr, index,
1484 					 include);
1485 
1486 	return res;
1487 }
1488 
1489 /**
1490  * sas_configure_parent - configure routing table of parent
1491  * @parent: parent expander
1492  * @child: child expander
1493  * @sas_addr: SAS port identifier of device directly attached to child
1494  * @include: whether or not to include @child in the expander routing table
1495  */
1496 static int sas_configure_parent(struct domain_device *parent,
1497 				struct domain_device *child,
1498 				u8 *sas_addr, int include)
1499 {
1500 	struct expander_device *ex_parent = &parent->ex_dev;
1501 	int res = 0;
1502 	int i;
1503 
1504 	if (parent->parent) {
1505 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1506 					   include);
1507 		if (res)
1508 			return res;
1509 	}
1510 
1511 	if (ex_parent->conf_route_table == 0) {
1512 		pr_debug("ex %016llx has self-configuring routing table\n",
1513 			 SAS_ADDR(parent->sas_addr));
1514 		return 0;
1515 	}
1516 
1517 	for (i = 0; i < ex_parent->num_phys; i++) {
1518 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1519 
1520 		if ((phy->routing_attr == TABLE_ROUTING) &&
1521 		    sas_phy_match_dev_addr(child, phy)) {
1522 			res = sas_configure_phy(parent, i, sas_addr, include);
1523 			if (res)
1524 				return res;
1525 		}
1526 	}
1527 
1528 	return res;
1529 }
1530 
1531 /**
1532  * sas_configure_routing - configure routing
1533  * @dev: expander device
1534  * @sas_addr: port identifier of device directly attached to the expander device
1535  */
1536 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1537 {
1538 	if (dev->parent)
1539 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1540 	return 0;
1541 }
1542 
1543 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1544 {
1545 	if (dev->parent)
1546 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1547 	return 0;
1548 }
1549 
1550 /**
1551  * sas_discover_expander - expander discovery
1552  * @dev: pointer to expander domain device
1553  *
1554  * See comment in sas_discover_sata().
1555  */
1556 static int sas_discover_expander(struct domain_device *dev)
1557 {
1558 	int res;
1559 
1560 	res = sas_notify_lldd_dev_found(dev);
1561 	if (res)
1562 		return res;
1563 
1564 	res = sas_ex_general(dev);
1565 	if (res)
1566 		goto out_err;
1567 	res = sas_ex_manuf_info(dev);
1568 	if (res)
1569 		goto out_err;
1570 
1571 	res = sas_expander_discover(dev);
1572 	if (res) {
1573 		pr_warn("expander %016llx discovery failed(0x%x)\n",
1574 			SAS_ADDR(dev->sas_addr), res);
1575 		goto out_err;
1576 	}
1577 
1578 	sas_check_ex_subtractive_boundary(dev);
1579 	res = sas_check_parent_topology(dev);
1580 	if (res)
1581 		goto out_err;
1582 	return 0;
1583 out_err:
1584 	sas_notify_lldd_dev_gone(dev);
1585 	return res;
1586 }
1587 
1588 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1589 {
1590 	int res = 0;
1591 	struct domain_device *dev;
1592 
1593 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1594 		if (dev_is_expander(dev->dev_type)) {
1595 			struct sas_expander_device *ex =
1596 				rphy_to_expander_device(dev->rphy);
1597 
1598 			if (level == ex->level)
1599 				res = sas_ex_discover_devices(dev, -1);
1600 			else if (level > 0)
1601 				res = sas_ex_discover_devices(port->port_dev, -1);
1602 
1603 		}
1604 	}
1605 
1606 	return res;
1607 }
1608 
1609 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1610 {
1611 	int res;
1612 	int level;
1613 
1614 	do {
1615 		level = port->disc.max_level;
1616 		res = sas_ex_level_discovery(port, level);
1617 		mb();
1618 	} while (level < port->disc.max_level);
1619 
1620 	return res;
1621 }
1622 
1623 int sas_discover_root_expander(struct domain_device *dev)
1624 {
1625 	int res;
1626 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1627 
1628 	res = sas_rphy_add(dev->rphy);
1629 	if (res)
1630 		goto out_err;
1631 
1632 	ex->level = dev->port->disc.max_level; /* 0 */
1633 	res = sas_discover_expander(dev);
1634 	if (res)
1635 		goto out_err2;
1636 
1637 	sas_ex_bfs_disc(dev->port);
1638 
1639 	return res;
1640 
1641 out_err2:
1642 	sas_rphy_remove(dev->rphy);
1643 out_err:
1644 	return res;
1645 }
1646 
1647 /* ---------- Domain revalidation ---------- */
1648 
1649 static void sas_get_sas_addr_and_dev_type(struct smp_disc_resp *disc_resp,
1650 					  u8 *sas_addr,
1651 					  enum sas_device_type *type)
1652 {
1653 	memcpy(sas_addr, disc_resp->disc.attached_sas_addr, SAS_ADDR_SIZE);
1654 	*type = to_dev_type(&disc_resp->disc);
1655 	if (*type == SAS_PHY_UNUSED)
1656 		memset(sas_addr, 0, SAS_ADDR_SIZE);
1657 }
1658 
1659 static int sas_get_phy_discover(struct domain_device *dev,
1660 				int phy_id, struct smp_disc_resp *disc_resp)
1661 {
1662 	int res;
1663 	u8 *disc_req;
1664 
1665 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1666 	if (!disc_req)
1667 		return -ENOMEM;
1668 
1669 	disc_req[1] = SMP_DISCOVER;
1670 	disc_req[9] = phy_id;
1671 
1672 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1673 			       disc_resp, DISCOVER_RESP_SIZE);
1674 	if (res)
1675 		goto out;
1676 	if (disc_resp->result != SMP_RESP_FUNC_ACC)
1677 		res = disc_resp->result;
1678 out:
1679 	kfree(disc_req);
1680 	return res;
1681 }
1682 
1683 static int sas_get_phy_change_count(struct domain_device *dev,
1684 				    int phy_id, int *pcc)
1685 {
1686 	int res;
1687 	struct smp_disc_resp *disc_resp;
1688 
1689 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1690 	if (!disc_resp)
1691 		return -ENOMEM;
1692 
1693 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1694 	if (!res)
1695 		*pcc = disc_resp->disc.change_count;
1696 
1697 	kfree(disc_resp);
1698 	return res;
1699 }
1700 
1701 int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
1702 			     u8 *sas_addr, enum sas_device_type *type)
1703 {
1704 	int res;
1705 	struct smp_disc_resp *disc_resp;
1706 
1707 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1708 	if (!disc_resp)
1709 		return -ENOMEM;
1710 
1711 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1712 	if (res == 0)
1713 		sas_get_sas_addr_and_dev_type(disc_resp, sas_addr, type);
1714 	kfree(disc_resp);
1715 	return res;
1716 }
1717 
1718 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1719 			      int from_phy, bool update)
1720 {
1721 	struct expander_device *ex = &dev->ex_dev;
1722 	int res = 0;
1723 	int i;
1724 
1725 	for (i = from_phy; i < ex->num_phys; i++) {
1726 		int phy_change_count = 0;
1727 
1728 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1729 		switch (res) {
1730 		case SMP_RESP_PHY_VACANT:
1731 		case SMP_RESP_NO_PHY:
1732 			continue;
1733 		case SMP_RESP_FUNC_ACC:
1734 			break;
1735 		default:
1736 			return res;
1737 		}
1738 
1739 		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1740 			if (update)
1741 				ex->ex_phy[i].phy_change_count =
1742 					phy_change_count;
1743 			*phy_id = i;
1744 			return 0;
1745 		}
1746 	}
1747 	return 0;
1748 }
1749 
1750 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1751 {
1752 	int res;
1753 	u8  *rg_req;
1754 	struct smp_rg_resp  *rg_resp;
1755 
1756 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1757 	if (!rg_req)
1758 		return -ENOMEM;
1759 
1760 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1761 	if (!rg_resp) {
1762 		kfree(rg_req);
1763 		return -ENOMEM;
1764 	}
1765 
1766 	rg_req[1] = SMP_REPORT_GENERAL;
1767 
1768 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1769 			       RG_RESP_SIZE);
1770 	if (res)
1771 		goto out;
1772 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1773 		res = rg_resp->result;
1774 		goto out;
1775 	}
1776 
1777 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1778 out:
1779 	kfree(rg_resp);
1780 	kfree(rg_req);
1781 	return res;
1782 }
1783 /**
1784  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1785  * @dev:domain device to be detect.
1786  * @src_dev: the device which originated BROADCAST(CHANGE).
1787  *
1788  * Add self-configuration expander support. Suppose two expander cascading,
1789  * when the first level expander is self-configuring, hotplug the disks in
1790  * second level expander, BROADCAST(CHANGE) will not only be originated
1791  * in the second level expander, but also be originated in the first level
1792  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1793  * expander changed count in two level expanders will all increment at least
1794  * once, but the phy which chang count has changed is the source device which
1795  * we concerned.
1796  */
1797 
1798 static int sas_find_bcast_dev(struct domain_device *dev,
1799 			      struct domain_device **src_dev)
1800 {
1801 	struct expander_device *ex = &dev->ex_dev;
1802 	int ex_change_count = -1;
1803 	int phy_id = -1;
1804 	int res;
1805 	struct domain_device *ch;
1806 
1807 	res = sas_get_ex_change_count(dev, &ex_change_count);
1808 	if (res)
1809 		goto out;
1810 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1811 		/* Just detect if this expander phys phy change count changed,
1812 		* in order to determine if this expander originate BROADCAST,
1813 		* and do not update phy change count field in our structure.
1814 		*/
1815 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1816 		if (phy_id != -1) {
1817 			*src_dev = dev;
1818 			ex->ex_change_count = ex_change_count;
1819 			pr_info("ex %016llx phy%02d change count has changed\n",
1820 				SAS_ADDR(dev->sas_addr), phy_id);
1821 			return res;
1822 		} else
1823 			pr_info("ex %016llx phys DID NOT change\n",
1824 				SAS_ADDR(dev->sas_addr));
1825 	}
1826 	list_for_each_entry(ch, &ex->children, siblings) {
1827 		if (dev_is_expander(ch->dev_type)) {
1828 			res = sas_find_bcast_dev(ch, src_dev);
1829 			if (*src_dev)
1830 				return res;
1831 		}
1832 	}
1833 out:
1834 	return res;
1835 }
1836 
1837 static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
1838 {
1839 	struct expander_device *ex = &dev->ex_dev;
1840 	struct domain_device *child, *n;
1841 
1842 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1843 		set_bit(SAS_DEV_GONE, &child->state);
1844 		if (dev_is_expander(child->dev_type))
1845 			sas_unregister_ex_tree(port, child);
1846 		else
1847 			sas_unregister_dev(port, child);
1848 	}
1849 	sas_unregister_dev(port, dev);
1850 }
1851 
1852 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1853 					 int phy_id, bool last)
1854 {
1855 	struct expander_device *ex_dev = &parent->ex_dev;
1856 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1857 	struct domain_device *child, *n, *found = NULL;
1858 	if (last) {
1859 		list_for_each_entry_safe(child, n,
1860 			&ex_dev->children, siblings) {
1861 			if (sas_phy_match_dev_addr(child, phy)) {
1862 				set_bit(SAS_DEV_GONE, &child->state);
1863 				if (dev_is_expander(child->dev_type))
1864 					sas_unregister_ex_tree(parent->port, child);
1865 				else
1866 					sas_unregister_dev(parent->port, child);
1867 				found = child;
1868 				break;
1869 			}
1870 		}
1871 		sas_disable_routing(parent, phy->attached_sas_addr);
1872 	}
1873 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1874 	if (phy->port) {
1875 		sas_port_delete_phy(phy->port, phy->phy);
1876 		sas_device_set_phy(found, phy->port);
1877 		if (phy->port->num_phys == 0) {
1878 			list_add_tail(&phy->port->del_list,
1879 				&parent->port->sas_port_del_list);
1880 			if (ex_dev->parent_port == phy->port)
1881 				ex_dev->parent_port = NULL;
1882 		}
1883 		phy->port = NULL;
1884 	}
1885 }
1886 
1887 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1888 					  const int level)
1889 {
1890 	struct expander_device *ex_root = &root->ex_dev;
1891 	struct domain_device *child;
1892 	int res = 0;
1893 
1894 	list_for_each_entry(child, &ex_root->children, siblings) {
1895 		if (dev_is_expander(child->dev_type)) {
1896 			struct sas_expander_device *ex =
1897 				rphy_to_expander_device(child->rphy);
1898 
1899 			if (level > ex->level)
1900 				res = sas_discover_bfs_by_root_level(child,
1901 								     level);
1902 			else if (level == ex->level)
1903 				res = sas_ex_discover_devices(child, -1);
1904 		}
1905 	}
1906 	return res;
1907 }
1908 
1909 static int sas_discover_bfs_by_root(struct domain_device *dev)
1910 {
1911 	int res;
1912 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1913 	int level = ex->level+1;
1914 
1915 	res = sas_ex_discover_devices(dev, -1);
1916 	if (res)
1917 		goto out;
1918 	do {
1919 		res = sas_discover_bfs_by_root_level(dev, level);
1920 		mb();
1921 		level += 1;
1922 	} while (level <= dev->port->disc.max_level);
1923 out:
1924 	return res;
1925 }
1926 
1927 static int sas_discover_new(struct domain_device *dev, int phy_id)
1928 {
1929 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1930 	struct domain_device *child;
1931 	int res;
1932 
1933 	pr_debug("ex %016llx phy%02d new device attached\n",
1934 		 SAS_ADDR(dev->sas_addr), phy_id);
1935 	res = sas_ex_phy_discover(dev, phy_id);
1936 	if (res)
1937 		return res;
1938 
1939 	if (sas_ex_join_wide_port(dev, phy_id))
1940 		return 0;
1941 
1942 	res = sas_ex_discover_devices(dev, phy_id);
1943 	if (res)
1944 		return res;
1945 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1946 		if (sas_phy_match_dev_addr(child, ex_phy)) {
1947 			if (dev_is_expander(child->dev_type))
1948 				res = sas_discover_bfs_by_root(child);
1949 			break;
1950 		}
1951 	}
1952 	return res;
1953 }
1954 
1955 static bool dev_type_flutter(enum sas_device_type new, enum sas_device_type old)
1956 {
1957 	if (old == new)
1958 		return true;
1959 
1960 	/* treat device directed resets as flutter, if we went
1961 	 * SAS_END_DEVICE to SAS_SATA_PENDING the link needs recovery
1962 	 */
1963 	if ((old == SAS_SATA_PENDING && new == SAS_END_DEVICE) ||
1964 	    (old == SAS_END_DEVICE && new == SAS_SATA_PENDING))
1965 		return true;
1966 
1967 	return false;
1968 }
1969 
1970 static void sas_rediscover_ex_phy(struct domain_device *dev, int phy_id,
1971 				  bool last)
1972 {
1973 	struct expander_device *ex = &dev->ex_dev;
1974 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1975 
1976 	phy->phy_change_count = -1;
1977 	ex->ex_change_count = -1;
1978 	sas_unregister_devs_sas_addr(dev, phy_id, last);
1979 	sas_discover_event(dev->port, DISCE_REVALIDATE_DOMAIN);
1980 }
1981 
1982 static bool sas_dev_is_flutter(struct domain_device *dev, int phy_id,
1983 			       u8 *sas_addr, enum sas_device_type type)
1984 {
1985 	struct expander_device *ex = &dev->ex_dev;
1986 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1987 	struct domain_device *child_dev;
1988 	char *action = "";
1989 	int res;
1990 
1991 	if (SAS_ADDR(sas_addr) != SAS_ADDR(phy->attached_sas_addr) ||
1992 	    !dev_type_flutter(type, phy->attached_dev_type))
1993 		return false;
1994 
1995 	res = sas_ex_phy_discover(dev, phy_id);
1996 	if (res)
1997 		return false;
1998 
1999 	child_dev = sas_ex_phy_to_dev(dev, phy_id);
2000 	if (!child_dev)
2001 		goto out;
2002 
2003 	if (dev_is_sata(child_dev) &&
2004 	    phy->attached_dev_type == SAS_SATA_PENDING) {
2005 		action = ", needs recovery";
2006 		goto out;
2007 	}
2008 
2009 	if (SAS_ADDR(child_dev->sas_addr) != SAS_ADDR(phy->attached_sas_addr)) {
2010 		pr_info("ex %016llx phy%02d sas_addr changed from %016llx to %016llx\n",
2011 			SAS_ADDR(dev->sas_addr), phy_id,
2012 			SAS_ADDR(child_dev->sas_addr),
2013 			SAS_ADDR(phy->attached_sas_addr));
2014 		/*
2015 		 * Device unregistering relies on address matching. Restore
2016 		 * attached_sas_addr back to the original address so that the old
2017 		 * device can be unregistered later
2018 		 */
2019 		memcpy(phy->attached_sas_addr, child_dev->sas_addr, SAS_ADDR_SIZE);
2020 		return false;
2021 	}
2022 
2023 	if (child_dev->linkrate != phy->linkrate) {
2024 		pr_info("ex %016llx phy%02d linkrate changed from %d to %d\n",
2025 			SAS_ADDR(dev->sas_addr), phy_id,
2026 			child_dev->linkrate, phy->linkrate);
2027 		return false;
2028 	}
2029 
2030 out:
2031 	pr_debug("ex %016llx phy%02d broadcast flutter%s\n",
2032 		 SAS_ADDR(dev->sas_addr), phy_id, action);
2033 	return true;
2034 }
2035 
2036 static int sas_rediscover_dev(struct domain_device *dev, int phy_id,
2037 			      bool last, int sibling)
2038 {
2039 	struct expander_device *ex = &dev->ex_dev;
2040 	struct ex_phy *phy = &ex->ex_phy[phy_id];
2041 	enum sas_device_type type = SAS_PHY_UNUSED;
2042 	struct smp_disc_resp *disc_resp;
2043 	u8 sas_addr[SAS_ADDR_SIZE];
2044 	char msg[80] = "";
2045 	int res;
2046 
2047 	if (!last)
2048 		sprintf(msg, ", part of a wide port with phy%02d", sibling);
2049 
2050 	pr_debug("ex %016llx rediscovering phy%02d%s\n",
2051 		 SAS_ADDR(dev->sas_addr), phy_id, msg);
2052 
2053 	memset(sas_addr, 0, SAS_ADDR_SIZE);
2054 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
2055 	if (!disc_resp)
2056 		return -ENOMEM;
2057 
2058 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
2059 	switch (res) {
2060 	case SMP_RESP_NO_PHY:
2061 		phy->phy_state = PHY_NOT_PRESENT;
2062 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2063 		goto out_free_resp;
2064 	case SMP_RESP_PHY_VACANT:
2065 		phy->phy_state = PHY_VACANT;
2066 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2067 		goto out_free_resp;
2068 	case SMP_RESP_FUNC_ACC:
2069 		break;
2070 	case -ECOMM:
2071 		break;
2072 	default:
2073 		goto out_free_resp;
2074 	}
2075 
2076 	if (res == 0)
2077 		sas_get_sas_addr_and_dev_type(disc_resp, sas_addr, &type);
2078 
2079 	if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM)) {
2080 		phy->phy_state = PHY_EMPTY;
2081 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2082 		/*
2083 		 * Even though the PHY is empty, for convenience we update
2084 		 * the PHY info, like negotiated linkrate.
2085 		 */
2086 		if (res == 0)
2087 			sas_set_ex_phy(dev, phy_id, disc_resp);
2088 		goto out_free_resp;
2089 	}
2090 
2091 	if (sas_dev_is_flutter(dev, phy_id, sas_addr, type))
2092 		goto out_free_resp;
2093 
2094 	/* we always have to delete the old device when we went here */
2095 	pr_info("ex %016llx phy%02d replace %016llx\n",
2096 		SAS_ADDR(dev->sas_addr), phy_id,
2097 		SAS_ADDR(phy->attached_sas_addr));
2098 	sas_rediscover_ex_phy(dev, phy_id, last);
2099 out_free_resp:
2100 	kfree(disc_resp);
2101 	return res;
2102 }
2103 
2104 /**
2105  * sas_rediscover - revalidate the domain.
2106  * @dev:domain device to be detect.
2107  * @phy_id: the phy id will be detected.
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.For plugging out, we un-register the device only when it is
2113  * the last phy in the port, for other phys in this port, we just delete it
2114  * from the port.For inserting, we do discovery when it is the
2115  * first phy,for other phys in this port, we add it to the port to
2116  * forming the wide-port.
2117  */
2118 static int sas_rediscover(struct domain_device *dev, const int phy_id)
2119 {
2120 	struct expander_device *ex = &dev->ex_dev;
2121 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
2122 	int res = 0;
2123 	int i;
2124 	bool last = true;	/* is this the last phy of the port */
2125 
2126 	pr_debug("ex %016llx phy%02d originated BROADCAST(CHANGE)\n",
2127 		 SAS_ADDR(dev->sas_addr), phy_id);
2128 
2129 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
2130 		for (i = 0; i < ex->num_phys; i++) {
2131 			struct ex_phy *phy = &ex->ex_phy[i];
2132 
2133 			if (i == phy_id)
2134 				continue;
2135 			if (sas_phy_addr_match(phy, changed_phy)) {
2136 				last = false;
2137 				break;
2138 			}
2139 		}
2140 		res = sas_rediscover_dev(dev, phy_id, last, i);
2141 	} else
2142 		res = sas_discover_new(dev, phy_id);
2143 	return res;
2144 }
2145 
2146 /**
2147  * sas_ex_revalidate_domain - revalidate the domain
2148  * @port_dev: port domain device.
2149  *
2150  * NOTE: this process _must_ quit (return) as soon as any connection
2151  * errors are encountered.  Connection recovery is done elsewhere.
2152  * Discover process only interrogates devices in order to discover the
2153  * domain.
2154  */
2155 int sas_ex_revalidate_domain(struct domain_device *port_dev)
2156 {
2157 	int res;
2158 	struct domain_device *dev = NULL;
2159 
2160 	res = sas_find_bcast_dev(port_dev, &dev);
2161 	if (res == 0 && dev) {
2162 		struct expander_device *ex = &dev->ex_dev;
2163 		int i = 0, phy_id;
2164 
2165 		do {
2166 			phy_id = -1;
2167 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
2168 			if (phy_id == -1)
2169 				break;
2170 			res = sas_rediscover(dev, phy_id);
2171 			i = phy_id + 1;
2172 		} while (i < ex->num_phys);
2173 	}
2174 	return res;
2175 }
2176 
2177 int sas_find_attached_phy_id(struct expander_device *ex_dev,
2178 			     struct domain_device *dev)
2179 {
2180 	struct ex_phy *phy;
2181 	int phy_id;
2182 
2183 	for (phy_id = 0; phy_id < ex_dev->num_phys; phy_id++) {
2184 		phy = &ex_dev->ex_phy[phy_id];
2185 		if (sas_phy_match_dev_addr(dev, phy))
2186 			return phy_id;
2187 	}
2188 
2189 	return -ENODEV;
2190 }
2191 EXPORT_SYMBOL_GPL(sas_find_attached_phy_id);
2192 
2193 void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
2194 		struct sas_rphy *rphy)
2195 {
2196 	struct domain_device *dev;
2197 	unsigned int rcvlen = 0;
2198 	int ret = -EINVAL;
2199 
2200 	/* no rphy means no smp target support (ie aic94xx host) */
2201 	if (!rphy)
2202 		return sas_smp_host_handler(job, shost);
2203 
2204 	switch (rphy->identify.device_type) {
2205 	case SAS_EDGE_EXPANDER_DEVICE:
2206 	case SAS_FANOUT_EXPANDER_DEVICE:
2207 		break;
2208 	default:
2209 		pr_err("%s: can we send a smp request to a device?\n",
2210 		       __func__);
2211 		goto out;
2212 	}
2213 
2214 	dev = sas_find_dev_by_rphy(rphy);
2215 	if (!dev) {
2216 		pr_err("%s: fail to find a domain_device?\n", __func__);
2217 		goto out;
2218 	}
2219 
2220 	/* do we need to support multiple segments? */
2221 	if (job->request_payload.sg_cnt > 1 ||
2222 	    job->reply_payload.sg_cnt > 1) {
2223 		pr_info("%s: multiple segments req %u, rsp %u\n",
2224 			__func__, job->request_payload.payload_len,
2225 			job->reply_payload.payload_len);
2226 		goto out;
2227 	}
2228 
2229 	/* The host may have autosuspended, resume it here. */
2230 	ret = pm_runtime_resume_and_get(dev->port->ha->dev);
2231 	if (ret)
2232 		goto out;
2233 
2234 	ret = smp_execute_task_sg(dev, job->request_payload.sg_list,
2235 			job->reply_payload.sg_list);
2236 	if (ret >= 0) {
2237 		/* bsg_job_done() requires the length received  */
2238 		rcvlen = job->reply_payload.payload_len - ret;
2239 		ret = 0;
2240 	}
2241 	pm_runtime_put(dev->port->ha->dev);
2242 
2243 out:
2244 	bsg_job_done(job, ret, rcvlen);
2245 }
2246