1 /*
2  * Serial Attached SCSI (SAS) Expander discovery and configuration
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
22  *
23  */
24 
25 #include <linux/scatterlist.h>
26 #include <linux/blkdev.h>
27 #include <linux/slab.h>
28 
29 #include "sas_internal.h"
30 
31 #include <scsi/sas_ata.h>
32 #include <scsi/scsi_transport.h>
33 #include <scsi/scsi_transport_sas.h>
34 #include "../scsi_sas_internal.h"
35 
36 static int sas_discover_expander(struct domain_device *dev);
37 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
38 static int sas_configure_phy(struct domain_device *dev, int phy_id,
39 			     u8 *sas_addr, int include);
40 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
41 
42 /* ---------- SMP task management ---------- */
43 
44 static void smp_task_timedout(unsigned long _task)
45 {
46 	struct sas_task *task = (void *) _task;
47 	unsigned long flags;
48 
49 	spin_lock_irqsave(&task->task_state_lock, flags);
50 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
51 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
52 	spin_unlock_irqrestore(&task->task_state_lock, flags);
53 
54 	complete(&task->slow_task->completion);
55 }
56 
57 static void smp_task_done(struct sas_task *task)
58 {
59 	if (!del_timer(&task->slow_task->timer))
60 		return;
61 	complete(&task->slow_task->completion);
62 }
63 
64 /* Give it some long enough timeout. In seconds. */
65 #define SMP_TIMEOUT 10
66 
67 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
68 			    void *resp, int resp_size)
69 {
70 	int res, retry;
71 	struct sas_task *task = NULL;
72 	struct sas_internal *i =
73 		to_sas_internal(dev->port->ha->core.shost->transportt);
74 
75 	mutex_lock(&dev->ex_dev.cmd_mutex);
76 	for (retry = 0; retry < 3; retry++) {
77 		if (test_bit(SAS_DEV_GONE, &dev->state)) {
78 			res = -ECOMM;
79 			break;
80 		}
81 
82 		task = sas_alloc_slow_task(GFP_KERNEL);
83 		if (!task) {
84 			res = -ENOMEM;
85 			break;
86 		}
87 		task->dev = dev;
88 		task->task_proto = dev->tproto;
89 		sg_init_one(&task->smp_task.smp_req, req, req_size);
90 		sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
91 
92 		task->task_done = smp_task_done;
93 
94 		task->slow_task->timer.data = (unsigned long) task;
95 		task->slow_task->timer.function = smp_task_timedout;
96 		task->slow_task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
97 		add_timer(&task->slow_task->timer);
98 
99 		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
100 
101 		if (res) {
102 			del_timer(&task->slow_task->timer);
103 			SAS_DPRINTK("executing SMP task failed:%d\n", res);
104 			break;
105 		}
106 
107 		wait_for_completion(&task->slow_task->completion);
108 		res = -ECOMM;
109 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
110 			SAS_DPRINTK("smp task timed out or aborted\n");
111 			i->dft->lldd_abort_task(task);
112 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
113 				SAS_DPRINTK("SMP task aborted and not done\n");
114 				break;
115 			}
116 		}
117 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
118 		    task->task_status.stat == SAM_STAT_GOOD) {
119 			res = 0;
120 			break;
121 		}
122 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
123 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
124 			/* no error, but return the number of bytes of
125 			 * underrun */
126 			res = task->task_status.residual;
127 			break;
128 		}
129 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
130 		    task->task_status.stat == SAS_DATA_OVERRUN) {
131 			res = -EMSGSIZE;
132 			break;
133 		}
134 		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
135 		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
136 			break;
137 		else {
138 			SAS_DPRINTK("%s: task to dev %016llx response: 0x%x "
139 				    "status 0x%x\n", __func__,
140 				    SAS_ADDR(dev->sas_addr),
141 				    task->task_status.resp,
142 				    task->task_status.stat);
143 			sas_free_task(task);
144 			task = NULL;
145 		}
146 	}
147 	mutex_unlock(&dev->ex_dev.cmd_mutex);
148 
149 	BUG_ON(retry == 3 && task != NULL);
150 	sas_free_task(task);
151 	return res;
152 }
153 
154 /* ---------- Allocations ---------- */
155 
156 static inline void *alloc_smp_req(int size)
157 {
158 	u8 *p = kzalloc(size, GFP_KERNEL);
159 	if (p)
160 		p[0] = SMP_REQUEST;
161 	return p;
162 }
163 
164 static inline void *alloc_smp_resp(int size)
165 {
166 	return kzalloc(size, GFP_KERNEL);
167 }
168 
169 static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
170 {
171 	switch (phy->routing_attr) {
172 	case TABLE_ROUTING:
173 		if (dev->ex_dev.t2t_supp)
174 			return 'U';
175 		else
176 			return 'T';
177 	case DIRECT_ROUTING:
178 		return 'D';
179 	case SUBTRACTIVE_ROUTING:
180 		return 'S';
181 	default:
182 		return '?';
183 	}
184 }
185 
186 static enum sas_device_type to_dev_type(struct discover_resp *dr)
187 {
188 	/* This is detecting a failure to transmit initial dev to host
189 	 * FIS as described in section J.5 of sas-2 r16
190 	 */
191 	if (dr->attached_dev_type == SAS_PHY_UNUSED && dr->attached_sata_dev &&
192 	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
193 		return SAS_SATA_PENDING;
194 	else
195 		return dr->attached_dev_type;
196 }
197 
198 static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
199 {
200 	enum sas_device_type dev_type;
201 	enum sas_linkrate linkrate;
202 	u8 sas_addr[SAS_ADDR_SIZE];
203 	struct smp_resp *resp = rsp;
204 	struct discover_resp *dr = &resp->disc;
205 	struct sas_ha_struct *ha = dev->port->ha;
206 	struct expander_device *ex = &dev->ex_dev;
207 	struct ex_phy *phy = &ex->ex_phy[phy_id];
208 	struct sas_rphy *rphy = dev->rphy;
209 	bool new_phy = !phy->phy;
210 	char *type;
211 
212 	if (new_phy) {
213 		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
214 			return;
215 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
216 
217 		/* FIXME: error_handling */
218 		BUG_ON(!phy->phy);
219 	}
220 
221 	switch (resp->result) {
222 	case SMP_RESP_PHY_VACANT:
223 		phy->phy_state = PHY_VACANT;
224 		break;
225 	default:
226 		phy->phy_state = PHY_NOT_PRESENT;
227 		break;
228 	case SMP_RESP_FUNC_ACC:
229 		phy->phy_state = PHY_EMPTY; /* do not know yet */
230 		break;
231 	}
232 
233 	/* check if anything important changed to squelch debug */
234 	dev_type = phy->attached_dev_type;
235 	linkrate  = phy->linkrate;
236 	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
237 
238 	/* Handle vacant phy - rest of dr data is not valid so skip it */
239 	if (phy->phy_state == PHY_VACANT) {
240 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
241 		phy->attached_dev_type = SAS_PHY_UNUSED;
242 		if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
243 			phy->phy_id = phy_id;
244 			goto skip;
245 		} else
246 			goto out;
247 	}
248 
249 	phy->attached_dev_type = to_dev_type(dr);
250 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
251 		goto out;
252 	phy->phy_id = phy_id;
253 	phy->linkrate = dr->linkrate;
254 	phy->attached_sata_host = dr->attached_sata_host;
255 	phy->attached_sata_dev  = dr->attached_sata_dev;
256 	phy->attached_sata_ps   = dr->attached_sata_ps;
257 	phy->attached_iproto = dr->iproto << 1;
258 	phy->attached_tproto = dr->tproto << 1;
259 	/* help some expanders that fail to zero sas_address in the 'no
260 	 * device' case
261 	 */
262 	if (phy->attached_dev_type == SAS_PHY_UNUSED ||
263 	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
264 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
265 	else
266 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
267 	phy->attached_phy_id = dr->attached_phy_id;
268 	phy->phy_change_count = dr->change_count;
269 	phy->routing_attr = dr->routing_attr;
270 	phy->virtual = dr->virtual;
271 	phy->last_da_index = -1;
272 
273 	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
274 	phy->phy->identify.device_type = dr->attached_dev_type;
275 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
276 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
277 	if (!phy->attached_tproto && dr->attached_sata_dev)
278 		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
279 	phy->phy->identify.phy_identifier = phy_id;
280 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
281 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
282 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
283 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
284 	phy->phy->negotiated_linkrate = phy->linkrate;
285 
286  skip:
287 	if (new_phy)
288 		if (sas_phy_add(phy->phy)) {
289 			sas_phy_free(phy->phy);
290 			return;
291 		}
292 
293  out:
294 	switch (phy->attached_dev_type) {
295 	case SAS_SATA_PENDING:
296 		type = "stp pending";
297 		break;
298 	case SAS_PHY_UNUSED:
299 		type = "no device";
300 		break;
301 	case SAS_END_DEVICE:
302 		if (phy->attached_iproto) {
303 			if (phy->attached_tproto)
304 				type = "host+target";
305 			else
306 				type = "host";
307 		} else {
308 			if (dr->attached_sata_dev)
309 				type = "stp";
310 			else
311 				type = "ssp";
312 		}
313 		break;
314 	case SAS_EDGE_EXPANDER_DEVICE:
315 	case SAS_FANOUT_EXPANDER_DEVICE:
316 		type = "smp";
317 		break;
318 	default:
319 		type = "unknown";
320 	}
321 
322 	/* this routine is polled by libata error recovery so filter
323 	 * unimportant messages
324 	 */
325 	if (new_phy || phy->attached_dev_type != dev_type ||
326 	    phy->linkrate != linkrate ||
327 	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
328 		/* pass */;
329 	else
330 		return;
331 
332 	/* if the attached device type changed and ata_eh is active,
333 	 * make sure we run revalidation when eh completes (see:
334 	 * sas_enable_revalidation)
335 	 */
336 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
337 		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
338 
339 	SAS_DPRINTK("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
340 		    test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
341 		    SAS_ADDR(dev->sas_addr), phy->phy_id,
342 		    sas_route_char(dev, phy), phy->linkrate,
343 		    SAS_ADDR(phy->attached_sas_addr), type);
344 }
345 
346 /* check if we have an existing attached ata device on this expander phy */
347 struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
348 {
349 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
350 	struct domain_device *dev;
351 	struct sas_rphy *rphy;
352 
353 	if (!ex_phy->port)
354 		return NULL;
355 
356 	rphy = ex_phy->port->rphy;
357 	if (!rphy)
358 		return NULL;
359 
360 	dev = sas_find_dev_by_rphy(rphy);
361 
362 	if (dev && dev_is_sata(dev))
363 		return dev;
364 
365 	return NULL;
366 }
367 
368 #define DISCOVER_REQ_SIZE  16
369 #define DISCOVER_RESP_SIZE 56
370 
371 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
372 				      u8 *disc_resp, int single)
373 {
374 	struct discover_resp *dr;
375 	int res;
376 
377 	disc_req[9] = single;
378 
379 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
380 			       disc_resp, DISCOVER_RESP_SIZE);
381 	if (res)
382 		return res;
383 	dr = &((struct smp_resp *)disc_resp)->disc;
384 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
385 		sas_printk("Found loopback topology, just ignore it!\n");
386 		return 0;
387 	}
388 	sas_set_ex_phy(dev, single, disc_resp);
389 	return 0;
390 }
391 
392 int sas_ex_phy_discover(struct domain_device *dev, int single)
393 {
394 	struct expander_device *ex = &dev->ex_dev;
395 	int  res = 0;
396 	u8   *disc_req;
397 	u8   *disc_resp;
398 
399 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
400 	if (!disc_req)
401 		return -ENOMEM;
402 
403 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
404 	if (!disc_resp) {
405 		kfree(disc_req);
406 		return -ENOMEM;
407 	}
408 
409 	disc_req[1] = SMP_DISCOVER;
410 
411 	if (0 <= single && single < ex->num_phys) {
412 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
413 	} else {
414 		int i;
415 
416 		for (i = 0; i < ex->num_phys; i++) {
417 			res = sas_ex_phy_discover_helper(dev, disc_req,
418 							 disc_resp, i);
419 			if (res)
420 				goto out_err;
421 		}
422 	}
423 out_err:
424 	kfree(disc_resp);
425 	kfree(disc_req);
426 	return res;
427 }
428 
429 static int sas_expander_discover(struct domain_device *dev)
430 {
431 	struct expander_device *ex = &dev->ex_dev;
432 	int res = -ENOMEM;
433 
434 	ex->ex_phy = kzalloc(sizeof(*ex->ex_phy)*ex->num_phys, GFP_KERNEL);
435 	if (!ex->ex_phy)
436 		return -ENOMEM;
437 
438 	res = sas_ex_phy_discover(dev, -1);
439 	if (res)
440 		goto out_err;
441 
442 	return 0;
443  out_err:
444 	kfree(ex->ex_phy);
445 	ex->ex_phy = NULL;
446 	return res;
447 }
448 
449 #define MAX_EXPANDER_PHYS 128
450 
451 static void ex_assign_report_general(struct domain_device *dev,
452 					    struct smp_resp *resp)
453 {
454 	struct report_general_resp *rg = &resp->rg;
455 
456 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
457 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
458 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
459 	dev->ex_dev.t2t_supp = rg->t2t_supp;
460 	dev->ex_dev.conf_route_table = rg->conf_route_table;
461 	dev->ex_dev.configuring = rg->configuring;
462 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
463 }
464 
465 #define RG_REQ_SIZE   8
466 #define RG_RESP_SIZE 32
467 
468 static int sas_ex_general(struct domain_device *dev)
469 {
470 	u8 *rg_req;
471 	struct smp_resp *rg_resp;
472 	int res;
473 	int i;
474 
475 	rg_req = alloc_smp_req(RG_REQ_SIZE);
476 	if (!rg_req)
477 		return -ENOMEM;
478 
479 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
480 	if (!rg_resp) {
481 		kfree(rg_req);
482 		return -ENOMEM;
483 	}
484 
485 	rg_req[1] = SMP_REPORT_GENERAL;
486 
487 	for (i = 0; i < 5; i++) {
488 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
489 				       RG_RESP_SIZE);
490 
491 		if (res) {
492 			SAS_DPRINTK("RG to ex %016llx failed:0x%x\n",
493 				    SAS_ADDR(dev->sas_addr), res);
494 			goto out;
495 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
496 			SAS_DPRINTK("RG:ex %016llx returned SMP result:0x%x\n",
497 				    SAS_ADDR(dev->sas_addr), rg_resp->result);
498 			res = rg_resp->result;
499 			goto out;
500 		}
501 
502 		ex_assign_report_general(dev, rg_resp);
503 
504 		if (dev->ex_dev.configuring) {
505 			SAS_DPRINTK("RG: ex %llx self-configuring...\n",
506 				    SAS_ADDR(dev->sas_addr));
507 			schedule_timeout_interruptible(5*HZ);
508 		} else
509 			break;
510 	}
511 out:
512 	kfree(rg_req);
513 	kfree(rg_resp);
514 	return res;
515 }
516 
517 static void ex_assign_manuf_info(struct domain_device *dev, void
518 					*_mi_resp)
519 {
520 	u8 *mi_resp = _mi_resp;
521 	struct sas_rphy *rphy = dev->rphy;
522 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
523 
524 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
525 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
526 	memcpy(edev->product_rev, mi_resp + 36,
527 	       SAS_EXPANDER_PRODUCT_REV_LEN);
528 
529 	if (mi_resp[8] & 1) {
530 		memcpy(edev->component_vendor_id, mi_resp + 40,
531 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
532 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
533 		edev->component_revision_id = mi_resp[50];
534 	}
535 }
536 
537 #define MI_REQ_SIZE   8
538 #define MI_RESP_SIZE 64
539 
540 static int sas_ex_manuf_info(struct domain_device *dev)
541 {
542 	u8 *mi_req;
543 	u8 *mi_resp;
544 	int res;
545 
546 	mi_req = alloc_smp_req(MI_REQ_SIZE);
547 	if (!mi_req)
548 		return -ENOMEM;
549 
550 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
551 	if (!mi_resp) {
552 		kfree(mi_req);
553 		return -ENOMEM;
554 	}
555 
556 	mi_req[1] = SMP_REPORT_MANUF_INFO;
557 
558 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
559 	if (res) {
560 		SAS_DPRINTK("MI: ex %016llx failed:0x%x\n",
561 			    SAS_ADDR(dev->sas_addr), res);
562 		goto out;
563 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
564 		SAS_DPRINTK("MI ex %016llx returned SMP result:0x%x\n",
565 			    SAS_ADDR(dev->sas_addr), mi_resp[2]);
566 		goto out;
567 	}
568 
569 	ex_assign_manuf_info(dev, mi_resp);
570 out:
571 	kfree(mi_req);
572 	kfree(mi_resp);
573 	return res;
574 }
575 
576 #define PC_REQ_SIZE  44
577 #define PC_RESP_SIZE 8
578 
579 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
580 			enum phy_func phy_func,
581 			struct sas_phy_linkrates *rates)
582 {
583 	u8 *pc_req;
584 	u8 *pc_resp;
585 	int res;
586 
587 	pc_req = alloc_smp_req(PC_REQ_SIZE);
588 	if (!pc_req)
589 		return -ENOMEM;
590 
591 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
592 	if (!pc_resp) {
593 		kfree(pc_req);
594 		return -ENOMEM;
595 	}
596 
597 	pc_req[1] = SMP_PHY_CONTROL;
598 	pc_req[9] = phy_id;
599 	pc_req[10]= phy_func;
600 	if (rates) {
601 		pc_req[32] = rates->minimum_linkrate << 4;
602 		pc_req[33] = rates->maximum_linkrate << 4;
603 	}
604 
605 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
606 
607 	kfree(pc_resp);
608 	kfree(pc_req);
609 	return res;
610 }
611 
612 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
613 {
614 	struct expander_device *ex = &dev->ex_dev;
615 	struct ex_phy *phy = &ex->ex_phy[phy_id];
616 
617 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
618 	phy->linkrate = SAS_PHY_DISABLED;
619 }
620 
621 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
622 {
623 	struct expander_device *ex = &dev->ex_dev;
624 	int i;
625 
626 	for (i = 0; i < ex->num_phys; i++) {
627 		struct ex_phy *phy = &ex->ex_phy[i];
628 
629 		if (phy->phy_state == PHY_VACANT ||
630 		    phy->phy_state == PHY_NOT_PRESENT)
631 			continue;
632 
633 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
634 			sas_ex_disable_phy(dev, i);
635 	}
636 }
637 
638 static int sas_dev_present_in_domain(struct asd_sas_port *port,
639 					    u8 *sas_addr)
640 {
641 	struct domain_device *dev;
642 
643 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
644 		return 1;
645 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
646 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
647 			return 1;
648 	}
649 	return 0;
650 }
651 
652 #define RPEL_REQ_SIZE	16
653 #define RPEL_RESP_SIZE	32
654 int sas_smp_get_phy_events(struct sas_phy *phy)
655 {
656 	int res;
657 	u8 *req;
658 	u8 *resp;
659 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
660 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
661 
662 	req = alloc_smp_req(RPEL_REQ_SIZE);
663 	if (!req)
664 		return -ENOMEM;
665 
666 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
667 	if (!resp) {
668 		kfree(req);
669 		return -ENOMEM;
670 	}
671 
672 	req[1] = SMP_REPORT_PHY_ERR_LOG;
673 	req[9] = phy->number;
674 
675 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
676 			            resp, RPEL_RESP_SIZE);
677 
678 	if (!res)
679 		goto out;
680 
681 	phy->invalid_dword_count = scsi_to_u32(&resp[12]);
682 	phy->running_disparity_error_count = scsi_to_u32(&resp[16]);
683 	phy->loss_of_dword_sync_count = scsi_to_u32(&resp[20]);
684 	phy->phy_reset_problem_count = scsi_to_u32(&resp[24]);
685 
686  out:
687 	kfree(resp);
688 	return res;
689 
690 }
691 
692 #ifdef CONFIG_SCSI_SAS_ATA
693 
694 #define RPS_REQ_SIZE  16
695 #define RPS_RESP_SIZE 60
696 
697 int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
698 			    struct smp_resp *rps_resp)
699 {
700 	int res;
701 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
702 	u8 *resp = (u8 *)rps_resp;
703 
704 	if (!rps_req)
705 		return -ENOMEM;
706 
707 	rps_req[1] = SMP_REPORT_PHY_SATA;
708 	rps_req[9] = phy_id;
709 
710 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
711 			            rps_resp, RPS_RESP_SIZE);
712 
713 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
714 	 * standards cockup here.  sas-2 explicitly specifies the FIS
715 	 * should be encoded so that FIS type is in resp[24].
716 	 * However, some expanders endian reverse this.  Undo the
717 	 * reversal here */
718 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
719 		int i;
720 
721 		for (i = 0; i < 5; i++) {
722 			int j = 24 + (i*4);
723 			u8 a, b;
724 			a = resp[j + 0];
725 			b = resp[j + 1];
726 			resp[j + 0] = resp[j + 3];
727 			resp[j + 1] = resp[j + 2];
728 			resp[j + 2] = b;
729 			resp[j + 3] = a;
730 		}
731 	}
732 
733 	kfree(rps_req);
734 	return res;
735 }
736 #endif
737 
738 static void sas_ex_get_linkrate(struct domain_device *parent,
739 				       struct domain_device *child,
740 				       struct ex_phy *parent_phy)
741 {
742 	struct expander_device *parent_ex = &parent->ex_dev;
743 	struct sas_port *port;
744 	int i;
745 
746 	child->pathways = 0;
747 
748 	port = parent_phy->port;
749 
750 	for (i = 0; i < parent_ex->num_phys; i++) {
751 		struct ex_phy *phy = &parent_ex->ex_phy[i];
752 
753 		if (phy->phy_state == PHY_VACANT ||
754 		    phy->phy_state == PHY_NOT_PRESENT)
755 			continue;
756 
757 		if (SAS_ADDR(phy->attached_sas_addr) ==
758 		    SAS_ADDR(child->sas_addr)) {
759 
760 			child->min_linkrate = min(parent->min_linkrate,
761 						  phy->linkrate);
762 			child->max_linkrate = max(parent->max_linkrate,
763 						  phy->linkrate);
764 			child->pathways++;
765 			sas_port_add_phy(port, phy->phy);
766 		}
767 	}
768 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
769 	child->pathways = min(child->pathways, parent->pathways);
770 }
771 
772 static struct domain_device *sas_ex_discover_end_dev(
773 	struct domain_device *parent, int phy_id)
774 {
775 	struct expander_device *parent_ex = &parent->ex_dev;
776 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
777 	struct domain_device *child = NULL;
778 	struct sas_rphy *rphy;
779 	int res;
780 
781 	if (phy->attached_sata_host || phy->attached_sata_ps)
782 		return NULL;
783 
784 	child = sas_alloc_device();
785 	if (!child)
786 		return NULL;
787 
788 	kref_get(&parent->kref);
789 	child->parent = parent;
790 	child->port   = parent->port;
791 	child->iproto = phy->attached_iproto;
792 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
793 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
794 	if (!phy->port) {
795 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
796 		if (unlikely(!phy->port))
797 			goto out_err;
798 		if (unlikely(sas_port_add(phy->port) != 0)) {
799 			sas_port_free(phy->port);
800 			goto out_err;
801 		}
802 	}
803 	sas_ex_get_linkrate(parent, child, phy);
804 	sas_device_set_phy(child, phy->port);
805 
806 #ifdef CONFIG_SCSI_SAS_ATA
807 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
808 		res = sas_get_ata_info(child, phy);
809 		if (res)
810 			goto out_free;
811 
812 		sas_init_dev(child);
813 		res = sas_ata_init(child);
814 		if (res)
815 			goto out_free;
816 		rphy = sas_end_device_alloc(phy->port);
817 		if (!rphy)
818 			goto out_free;
819 
820 		child->rphy = rphy;
821 		get_device(&rphy->dev);
822 
823 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
824 
825 		res = sas_discover_sata(child);
826 		if (res) {
827 			SAS_DPRINTK("sas_discover_sata() for device %16llx at "
828 				    "%016llx:0x%x returned 0x%x\n",
829 				    SAS_ADDR(child->sas_addr),
830 				    SAS_ADDR(parent->sas_addr), phy_id, res);
831 			goto out_list_del;
832 		}
833 	} else
834 #endif
835 	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
836 		child->dev_type = SAS_END_DEVICE;
837 		rphy = sas_end_device_alloc(phy->port);
838 		/* FIXME: error handling */
839 		if (unlikely(!rphy))
840 			goto out_free;
841 		child->tproto = phy->attached_tproto;
842 		sas_init_dev(child);
843 
844 		child->rphy = rphy;
845 		get_device(&rphy->dev);
846 		sas_fill_in_rphy(child, rphy);
847 
848 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
849 
850 		res = sas_discover_end_dev(child);
851 		if (res) {
852 			SAS_DPRINTK("sas_discover_end_dev() for device %16llx "
853 				    "at %016llx:0x%x returned 0x%x\n",
854 				    SAS_ADDR(child->sas_addr),
855 				    SAS_ADDR(parent->sas_addr), phy_id, res);
856 			goto out_list_del;
857 		}
858 	} else {
859 		SAS_DPRINTK("target proto 0x%x at %016llx:0x%x not handled\n",
860 			    phy->attached_tproto, SAS_ADDR(parent->sas_addr),
861 			    phy_id);
862 		goto out_free;
863 	}
864 
865 	list_add_tail(&child->siblings, &parent_ex->children);
866 	return child;
867 
868  out_list_del:
869 	sas_rphy_free(child->rphy);
870 	list_del(&child->disco_list_node);
871 	spin_lock_irq(&parent->port->dev_list_lock);
872 	list_del(&child->dev_list_node);
873 	spin_unlock_irq(&parent->port->dev_list_lock);
874  out_free:
875 	sas_port_delete(phy->port);
876  out_err:
877 	phy->port = NULL;
878 	sas_put_device(child);
879 	return NULL;
880 }
881 
882 /* See if this phy is part of a wide port */
883 static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
884 {
885 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
886 	int i;
887 
888 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
889 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
890 
891 		if (ephy == phy)
892 			continue;
893 
894 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
895 			    SAS_ADDR_SIZE) && ephy->port) {
896 			sas_port_add_phy(ephy->port, phy->phy);
897 			phy->port = ephy->port;
898 			phy->phy_state = PHY_DEVICE_DISCOVERED;
899 			return true;
900 		}
901 	}
902 
903 	return false;
904 }
905 
906 static struct domain_device *sas_ex_discover_expander(
907 	struct domain_device *parent, int phy_id)
908 {
909 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
910 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
911 	struct domain_device *child = NULL;
912 	struct sas_rphy *rphy;
913 	struct sas_expander_device *edev;
914 	struct asd_sas_port *port;
915 	int res;
916 
917 	if (phy->routing_attr == DIRECT_ROUTING) {
918 		SAS_DPRINTK("ex %016llx:0x%x:D <--> ex %016llx:0x%x is not "
919 			    "allowed\n",
920 			    SAS_ADDR(parent->sas_addr), phy_id,
921 			    SAS_ADDR(phy->attached_sas_addr),
922 			    phy->attached_phy_id);
923 		return NULL;
924 	}
925 	child = sas_alloc_device();
926 	if (!child)
927 		return NULL;
928 
929 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
930 	/* FIXME: better error handling */
931 	BUG_ON(sas_port_add(phy->port) != 0);
932 
933 
934 	switch (phy->attached_dev_type) {
935 	case SAS_EDGE_EXPANDER_DEVICE:
936 		rphy = sas_expander_alloc(phy->port,
937 					  SAS_EDGE_EXPANDER_DEVICE);
938 		break;
939 	case SAS_FANOUT_EXPANDER_DEVICE:
940 		rphy = sas_expander_alloc(phy->port,
941 					  SAS_FANOUT_EXPANDER_DEVICE);
942 		break;
943 	default:
944 		rphy = NULL;	/* shut gcc up */
945 		BUG();
946 	}
947 	port = parent->port;
948 	child->rphy = rphy;
949 	get_device(&rphy->dev);
950 	edev = rphy_to_expander_device(rphy);
951 	child->dev_type = phy->attached_dev_type;
952 	kref_get(&parent->kref);
953 	child->parent = parent;
954 	child->port = port;
955 	child->iproto = phy->attached_iproto;
956 	child->tproto = phy->attached_tproto;
957 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
958 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
959 	sas_ex_get_linkrate(parent, child, phy);
960 	edev->level = parent_ex->level + 1;
961 	parent->port->disc.max_level = max(parent->port->disc.max_level,
962 					   edev->level);
963 	sas_init_dev(child);
964 	sas_fill_in_rphy(child, rphy);
965 	sas_rphy_add(rphy);
966 
967 	spin_lock_irq(&parent->port->dev_list_lock);
968 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
969 	spin_unlock_irq(&parent->port->dev_list_lock);
970 
971 	res = sas_discover_expander(child);
972 	if (res) {
973 		sas_rphy_delete(rphy);
974 		spin_lock_irq(&parent->port->dev_list_lock);
975 		list_del(&child->dev_list_node);
976 		spin_unlock_irq(&parent->port->dev_list_lock);
977 		sas_put_device(child);
978 		return NULL;
979 	}
980 	list_add_tail(&child->siblings, &parent->ex_dev.children);
981 	return child;
982 }
983 
984 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
985 {
986 	struct expander_device *ex = &dev->ex_dev;
987 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
988 	struct domain_device *child = NULL;
989 	int res = 0;
990 
991 	/* Phy state */
992 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
993 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
994 			res = sas_ex_phy_discover(dev, phy_id);
995 		if (res)
996 			return res;
997 	}
998 
999 	/* Parent and domain coherency */
1000 	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
1001 			     SAS_ADDR(dev->port->sas_addr))) {
1002 		sas_add_parent_port(dev, phy_id);
1003 		return 0;
1004 	}
1005 	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
1006 			    SAS_ADDR(dev->parent->sas_addr))) {
1007 		sas_add_parent_port(dev, phy_id);
1008 		if (ex_phy->routing_attr == TABLE_ROUTING)
1009 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
1010 		return 0;
1011 	}
1012 
1013 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
1014 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
1015 
1016 	if (ex_phy->attached_dev_type == SAS_PHY_UNUSED) {
1017 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
1018 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1019 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
1020 		}
1021 		return 0;
1022 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
1023 		return 0;
1024 
1025 	if (ex_phy->attached_dev_type != SAS_END_DEVICE &&
1026 	    ex_phy->attached_dev_type != SAS_FANOUT_EXPANDER_DEVICE &&
1027 	    ex_phy->attached_dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1028 	    ex_phy->attached_dev_type != SAS_SATA_PENDING) {
1029 		SAS_DPRINTK("unknown device type(0x%x) attached to ex %016llx "
1030 			    "phy 0x%x\n", ex_phy->attached_dev_type,
1031 			    SAS_ADDR(dev->sas_addr),
1032 			    phy_id);
1033 		return 0;
1034 	}
1035 
1036 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
1037 	if (res) {
1038 		SAS_DPRINTK("configure routing for dev %016llx "
1039 			    "reported 0x%x. Forgotten\n",
1040 			    SAS_ADDR(ex_phy->attached_sas_addr), res);
1041 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
1042 		return res;
1043 	}
1044 
1045 	if (sas_ex_join_wide_port(dev, phy_id)) {
1046 		SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
1047 			    phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
1048 		return res;
1049 	}
1050 
1051 	switch (ex_phy->attached_dev_type) {
1052 	case SAS_END_DEVICE:
1053 	case SAS_SATA_PENDING:
1054 		child = sas_ex_discover_end_dev(dev, phy_id);
1055 		break;
1056 	case SAS_FANOUT_EXPANDER_DEVICE:
1057 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
1058 			SAS_DPRINTK("second fanout expander %016llx phy 0x%x "
1059 				    "attached to ex %016llx phy 0x%x\n",
1060 				    SAS_ADDR(ex_phy->attached_sas_addr),
1061 				    ex_phy->attached_phy_id,
1062 				    SAS_ADDR(dev->sas_addr),
1063 				    phy_id);
1064 			sas_ex_disable_phy(dev, phy_id);
1065 			break;
1066 		} else
1067 			memcpy(dev->port->disc.fanout_sas_addr,
1068 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
1069 		/* fallthrough */
1070 	case SAS_EDGE_EXPANDER_DEVICE:
1071 		child = sas_ex_discover_expander(dev, phy_id);
1072 		break;
1073 	default:
1074 		break;
1075 	}
1076 
1077 	if (child) {
1078 		int i;
1079 
1080 		for (i = 0; i < ex->num_phys; i++) {
1081 			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
1082 			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
1083 				continue;
1084 			/*
1085 			 * Due to races, the phy might not get added to the
1086 			 * wide port, so we add the phy to the wide port here.
1087 			 */
1088 			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
1089 			    SAS_ADDR(child->sas_addr)) {
1090 				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
1091 				if (sas_ex_join_wide_port(dev, i))
1092 					SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
1093 						    i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
1094 
1095 			}
1096 		}
1097 	}
1098 
1099 	return res;
1100 }
1101 
1102 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
1103 {
1104 	struct expander_device *ex = &dev->ex_dev;
1105 	int i;
1106 
1107 	for (i = 0; i < ex->num_phys; i++) {
1108 		struct ex_phy *phy = &ex->ex_phy[i];
1109 
1110 		if (phy->phy_state == PHY_VACANT ||
1111 		    phy->phy_state == PHY_NOT_PRESENT)
1112 			continue;
1113 
1114 		if ((phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1115 		     phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE) &&
1116 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1117 
1118 			memcpy(sub_addr, phy->attached_sas_addr,SAS_ADDR_SIZE);
1119 
1120 			return 1;
1121 		}
1122 	}
1123 	return 0;
1124 }
1125 
1126 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1127 {
1128 	struct expander_device *ex = &dev->ex_dev;
1129 	struct domain_device *child;
1130 	u8 sub_addr[8] = {0, };
1131 
1132 	list_for_each_entry(child, &ex->children, siblings) {
1133 		if (child->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1134 		    child->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
1135 			continue;
1136 		if (sub_addr[0] == 0) {
1137 			sas_find_sub_addr(child, sub_addr);
1138 			continue;
1139 		} else {
1140 			u8 s2[8];
1141 
1142 			if (sas_find_sub_addr(child, s2) &&
1143 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1144 
1145 				SAS_DPRINTK("ex %016llx->%016llx-?->%016llx "
1146 					    "diverges from subtractive "
1147 					    "boundary %016llx\n",
1148 					    SAS_ADDR(dev->sas_addr),
1149 					    SAS_ADDR(child->sas_addr),
1150 					    SAS_ADDR(s2),
1151 					    SAS_ADDR(sub_addr));
1152 
1153 				sas_ex_disable_port(child, s2);
1154 			}
1155 		}
1156 	}
1157 	return 0;
1158 }
1159 /**
1160  * sas_ex_discover_devices -- discover devices attached to this expander
1161  * dev: pointer to the expander domain device
1162  * single: if you want to do a single phy, else set to -1;
1163  *
1164  * Configure this expander for use with its devices and register the
1165  * devices of this expander.
1166  */
1167 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1168 {
1169 	struct expander_device *ex = &dev->ex_dev;
1170 	int i = 0, end = ex->num_phys;
1171 	int res = 0;
1172 
1173 	if (0 <= single && single < end) {
1174 		i = single;
1175 		end = i+1;
1176 	}
1177 
1178 	for ( ; i < end; i++) {
1179 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1180 
1181 		if (ex_phy->phy_state == PHY_VACANT ||
1182 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1183 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1184 			continue;
1185 
1186 		switch (ex_phy->linkrate) {
1187 		case SAS_PHY_DISABLED:
1188 		case SAS_PHY_RESET_PROBLEM:
1189 		case SAS_SATA_PORT_SELECTOR:
1190 			continue;
1191 		default:
1192 			res = sas_ex_discover_dev(dev, i);
1193 			if (res)
1194 				break;
1195 			continue;
1196 		}
1197 	}
1198 
1199 	if (!res)
1200 		sas_check_level_subtractive_boundary(dev);
1201 
1202 	return res;
1203 }
1204 
1205 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1206 {
1207 	struct expander_device *ex = &dev->ex_dev;
1208 	int i;
1209 	u8  *sub_sas_addr = NULL;
1210 
1211 	if (dev->dev_type != SAS_EDGE_EXPANDER_DEVICE)
1212 		return 0;
1213 
1214 	for (i = 0; i < ex->num_phys; i++) {
1215 		struct ex_phy *phy = &ex->ex_phy[i];
1216 
1217 		if (phy->phy_state == PHY_VACANT ||
1218 		    phy->phy_state == PHY_NOT_PRESENT)
1219 			continue;
1220 
1221 		if ((phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE ||
1222 		     phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE) &&
1223 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1224 
1225 			if (!sub_sas_addr)
1226 				sub_sas_addr = &phy->attached_sas_addr[0];
1227 			else if (SAS_ADDR(sub_sas_addr) !=
1228 				 SAS_ADDR(phy->attached_sas_addr)) {
1229 
1230 				SAS_DPRINTK("ex %016llx phy 0x%x "
1231 					    "diverges(%016llx) on subtractive "
1232 					    "boundary(%016llx). Disabled\n",
1233 					    SAS_ADDR(dev->sas_addr), i,
1234 					    SAS_ADDR(phy->attached_sas_addr),
1235 					    SAS_ADDR(sub_sas_addr));
1236 				sas_ex_disable_phy(dev, i);
1237 			}
1238 		}
1239 	}
1240 	return 0;
1241 }
1242 
1243 static void sas_print_parent_topology_bug(struct domain_device *child,
1244 						 struct ex_phy *parent_phy,
1245 						 struct ex_phy *child_phy)
1246 {
1247 	static const char *ex_type[] = {
1248 		[SAS_EDGE_EXPANDER_DEVICE] = "edge",
1249 		[SAS_FANOUT_EXPANDER_DEVICE] = "fanout",
1250 	};
1251 	struct domain_device *parent = child->parent;
1252 
1253 	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx "
1254 		   "phy 0x%x has %c:%c routing link!\n",
1255 
1256 		   ex_type[parent->dev_type],
1257 		   SAS_ADDR(parent->sas_addr),
1258 		   parent_phy->phy_id,
1259 
1260 		   ex_type[child->dev_type],
1261 		   SAS_ADDR(child->sas_addr),
1262 		   child_phy->phy_id,
1263 
1264 		   sas_route_char(parent, parent_phy),
1265 		   sas_route_char(child, child_phy));
1266 }
1267 
1268 static int sas_check_eeds(struct domain_device *child,
1269 				 struct ex_phy *parent_phy,
1270 				 struct ex_phy *child_phy)
1271 {
1272 	int res = 0;
1273 	struct domain_device *parent = child->parent;
1274 
1275 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1276 		res = -ENODEV;
1277 		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
1278 			    "phy S:0x%x, while there is a fanout ex %016llx\n",
1279 			    SAS_ADDR(parent->sas_addr),
1280 			    parent_phy->phy_id,
1281 			    SAS_ADDR(child->sas_addr),
1282 			    child_phy->phy_id,
1283 			    SAS_ADDR(parent->port->disc.fanout_sas_addr));
1284 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1285 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1286 		       SAS_ADDR_SIZE);
1287 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1288 		       SAS_ADDR_SIZE);
1289 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1290 		    SAS_ADDR(parent->sas_addr)) ||
1291 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1292 		    SAS_ADDR(child->sas_addr)))
1293 		   &&
1294 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1295 		     SAS_ADDR(parent->sas_addr)) ||
1296 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1297 		     SAS_ADDR(child->sas_addr))))
1298 		;
1299 	else {
1300 		res = -ENODEV;
1301 		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
1302 			    "phy 0x%x 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 (child->parent->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
1325 	    child->parent->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
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 		struct ex_phy *child_phy;
1333 
1334 		if (parent_phy->phy_state == PHY_VACANT ||
1335 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1336 			continue;
1337 
1338 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1339 			continue;
1340 
1341 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1342 
1343 		switch (child->parent->dev_type) {
1344 		case SAS_EDGE_EXPANDER_DEVICE:
1345 			if (child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1346 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1347 				    child_phy->routing_attr != TABLE_ROUTING) {
1348 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1349 					res = -ENODEV;
1350 				}
1351 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1352 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1353 					res = sas_check_eeds(child, parent_phy, child_phy);
1354 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1355 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1356 					res = -ENODEV;
1357 				}
1358 			} else if (parent_phy->routing_attr == TABLE_ROUTING) {
1359 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING ||
1360 				    (child_phy->routing_attr == TABLE_ROUTING &&
1361 				     child_ex->t2t_supp && parent_ex->t2t_supp)) {
1362 					/* All good */;
1363 				} else {
1364 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1365 					res = -ENODEV;
1366 				}
1367 			}
1368 			break;
1369 		case SAS_FANOUT_EXPANDER_DEVICE:
1370 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1371 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1372 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1373 				res = -ENODEV;
1374 			}
1375 			break;
1376 		default:
1377 			break;
1378 		}
1379 	}
1380 
1381 	return res;
1382 }
1383 
1384 #define RRI_REQ_SIZE  16
1385 #define RRI_RESP_SIZE 44
1386 
1387 static int sas_configure_present(struct domain_device *dev, int phy_id,
1388 				 u8 *sas_addr, int *index, int *present)
1389 {
1390 	int i, res = 0;
1391 	struct expander_device *ex = &dev->ex_dev;
1392 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1393 	u8 *rri_req;
1394 	u8 *rri_resp;
1395 
1396 	*present = 0;
1397 	*index = 0;
1398 
1399 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1400 	if (!rri_req)
1401 		return -ENOMEM;
1402 
1403 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1404 	if (!rri_resp) {
1405 		kfree(rri_req);
1406 		return -ENOMEM;
1407 	}
1408 
1409 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1410 	rri_req[9] = phy_id;
1411 
1412 	for (i = 0; i < ex->max_route_indexes ; i++) {
1413 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1414 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1415 				       RRI_RESP_SIZE);
1416 		if (res)
1417 			goto out;
1418 		res = rri_resp[2];
1419 		if (res == SMP_RESP_NO_INDEX) {
1420 			SAS_DPRINTK("overflow of indexes: dev %016llx "
1421 				    "phy 0x%x index 0x%x\n",
1422 				    SAS_ADDR(dev->sas_addr), phy_id, i);
1423 			goto out;
1424 		} else if (res != SMP_RESP_FUNC_ACC) {
1425 			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
1426 				    "result 0x%x\n", __func__,
1427 				    SAS_ADDR(dev->sas_addr), phy_id, i, res);
1428 			goto out;
1429 		}
1430 		if (SAS_ADDR(sas_addr) != 0) {
1431 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1432 				*index = i;
1433 				if ((rri_resp[12] & 0x80) == 0x80)
1434 					*present = 0;
1435 				else
1436 					*present = 1;
1437 				goto out;
1438 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1439 				*index = i;
1440 				*present = 0;
1441 				goto out;
1442 			}
1443 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1444 			   phy->last_da_index < i) {
1445 			phy->last_da_index = i;
1446 			*index = i;
1447 			*present = 0;
1448 			goto out;
1449 		}
1450 	}
1451 	res = -1;
1452 out:
1453 	kfree(rri_req);
1454 	kfree(rri_resp);
1455 	return res;
1456 }
1457 
1458 #define CRI_REQ_SIZE  44
1459 #define CRI_RESP_SIZE  8
1460 
1461 static int sas_configure_set(struct domain_device *dev, int phy_id,
1462 			     u8 *sas_addr, int index, int include)
1463 {
1464 	int res;
1465 	u8 *cri_req;
1466 	u8 *cri_resp;
1467 
1468 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1469 	if (!cri_req)
1470 		return -ENOMEM;
1471 
1472 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1473 	if (!cri_resp) {
1474 		kfree(cri_req);
1475 		return -ENOMEM;
1476 	}
1477 
1478 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1479 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1480 	cri_req[9] = phy_id;
1481 	if (SAS_ADDR(sas_addr) == 0 || !include)
1482 		cri_req[12] |= 0x80;
1483 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1484 
1485 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1486 			       CRI_RESP_SIZE);
1487 	if (res)
1488 		goto out;
1489 	res = cri_resp[2];
1490 	if (res == SMP_RESP_NO_INDEX) {
1491 		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
1492 			    "index 0x%x\n",
1493 			    SAS_ADDR(dev->sas_addr), phy_id, index);
1494 	}
1495 out:
1496 	kfree(cri_req);
1497 	kfree(cri_resp);
1498 	return res;
1499 }
1500 
1501 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1502 				    u8 *sas_addr, int include)
1503 {
1504 	int index;
1505 	int present;
1506 	int res;
1507 
1508 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1509 	if (res)
1510 		return res;
1511 	if (include ^ present)
1512 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1513 
1514 	return res;
1515 }
1516 
1517 /**
1518  * sas_configure_parent -- configure routing table of parent
1519  * parent: parent expander
1520  * child: child expander
1521  * sas_addr: SAS port identifier of device directly attached to child
1522  */
1523 static int sas_configure_parent(struct domain_device *parent,
1524 				struct domain_device *child,
1525 				u8 *sas_addr, int include)
1526 {
1527 	struct expander_device *ex_parent = &parent->ex_dev;
1528 	int res = 0;
1529 	int i;
1530 
1531 	if (parent->parent) {
1532 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1533 					   include);
1534 		if (res)
1535 			return res;
1536 	}
1537 
1538 	if (ex_parent->conf_route_table == 0) {
1539 		SAS_DPRINTK("ex %016llx has self-configuring routing table\n",
1540 			    SAS_ADDR(parent->sas_addr));
1541 		return 0;
1542 	}
1543 
1544 	for (i = 0; i < ex_parent->num_phys; i++) {
1545 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1546 
1547 		if ((phy->routing_attr == TABLE_ROUTING) &&
1548 		    (SAS_ADDR(phy->attached_sas_addr) ==
1549 		     SAS_ADDR(child->sas_addr))) {
1550 			res = sas_configure_phy(parent, i, sas_addr, include);
1551 			if (res)
1552 				return res;
1553 		}
1554 	}
1555 
1556 	return res;
1557 }
1558 
1559 /**
1560  * sas_configure_routing -- configure routing
1561  * dev: expander device
1562  * sas_addr: port identifier of device directly attached to the expander device
1563  */
1564 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1565 {
1566 	if (dev->parent)
1567 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1568 	return 0;
1569 }
1570 
1571 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1572 {
1573 	if (dev->parent)
1574 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1575 	return 0;
1576 }
1577 
1578 /**
1579  * sas_discover_expander -- expander discovery
1580  * @ex: pointer to expander domain device
1581  *
1582  * See comment in sas_discover_sata().
1583  */
1584 static int sas_discover_expander(struct domain_device *dev)
1585 {
1586 	int res;
1587 
1588 	res = sas_notify_lldd_dev_found(dev);
1589 	if (res)
1590 		return res;
1591 
1592 	res = sas_ex_general(dev);
1593 	if (res)
1594 		goto out_err;
1595 	res = sas_ex_manuf_info(dev);
1596 	if (res)
1597 		goto out_err;
1598 
1599 	res = sas_expander_discover(dev);
1600 	if (res) {
1601 		SAS_DPRINTK("expander %016llx discovery failed(0x%x)\n",
1602 			    SAS_ADDR(dev->sas_addr), res);
1603 		goto out_err;
1604 	}
1605 
1606 	sas_check_ex_subtractive_boundary(dev);
1607 	res = sas_check_parent_topology(dev);
1608 	if (res)
1609 		goto out_err;
1610 	return 0;
1611 out_err:
1612 	sas_notify_lldd_dev_gone(dev);
1613 	return res;
1614 }
1615 
1616 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1617 {
1618 	int res = 0;
1619 	struct domain_device *dev;
1620 
1621 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1622 		if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1623 		    dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1624 			struct sas_expander_device *ex =
1625 				rphy_to_expander_device(dev->rphy);
1626 
1627 			if (level == ex->level)
1628 				res = sas_ex_discover_devices(dev, -1);
1629 			else if (level > 0)
1630 				res = sas_ex_discover_devices(port->port_dev, -1);
1631 
1632 		}
1633 	}
1634 
1635 	return res;
1636 }
1637 
1638 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1639 {
1640 	int res;
1641 	int level;
1642 
1643 	do {
1644 		level = port->disc.max_level;
1645 		res = sas_ex_level_discovery(port, level);
1646 		mb();
1647 	} while (level < port->disc.max_level);
1648 
1649 	return res;
1650 }
1651 
1652 int sas_discover_root_expander(struct domain_device *dev)
1653 {
1654 	int res;
1655 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1656 
1657 	res = sas_rphy_add(dev->rphy);
1658 	if (res)
1659 		goto out_err;
1660 
1661 	ex->level = dev->port->disc.max_level; /* 0 */
1662 	res = sas_discover_expander(dev);
1663 	if (res)
1664 		goto out_err2;
1665 
1666 	sas_ex_bfs_disc(dev->port);
1667 
1668 	return res;
1669 
1670 out_err2:
1671 	sas_rphy_remove(dev->rphy);
1672 out_err:
1673 	return res;
1674 }
1675 
1676 /* ---------- Domain revalidation ---------- */
1677 
1678 static int sas_get_phy_discover(struct domain_device *dev,
1679 				int phy_id, struct smp_resp *disc_resp)
1680 {
1681 	int res;
1682 	u8 *disc_req;
1683 
1684 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1685 	if (!disc_req)
1686 		return -ENOMEM;
1687 
1688 	disc_req[1] = SMP_DISCOVER;
1689 	disc_req[9] = phy_id;
1690 
1691 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1692 			       disc_resp, DISCOVER_RESP_SIZE);
1693 	if (res)
1694 		goto out;
1695 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1696 		res = disc_resp->result;
1697 		goto out;
1698 	}
1699 out:
1700 	kfree(disc_req);
1701 	return res;
1702 }
1703 
1704 static int sas_get_phy_change_count(struct domain_device *dev,
1705 				    int phy_id, int *pcc)
1706 {
1707 	int res;
1708 	struct smp_resp *disc_resp;
1709 
1710 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1711 	if (!disc_resp)
1712 		return -ENOMEM;
1713 
1714 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1715 	if (!res)
1716 		*pcc = disc_resp->disc.change_count;
1717 
1718 	kfree(disc_resp);
1719 	return res;
1720 }
1721 
1722 static int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
1723 				    u8 *sas_addr, enum sas_device_type *type)
1724 {
1725 	int res;
1726 	struct smp_resp *disc_resp;
1727 	struct discover_resp *dr;
1728 
1729 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1730 	if (!disc_resp)
1731 		return -ENOMEM;
1732 	dr = &disc_resp->disc;
1733 
1734 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1735 	if (res == 0) {
1736 		memcpy(sas_addr, disc_resp->disc.attached_sas_addr, 8);
1737 		*type = to_dev_type(dr);
1738 		if (*type == 0)
1739 			memset(sas_addr, 0, 8);
1740 	}
1741 	kfree(disc_resp);
1742 	return res;
1743 }
1744 
1745 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1746 			      int from_phy, bool update)
1747 {
1748 	struct expander_device *ex = &dev->ex_dev;
1749 	int res = 0;
1750 	int i;
1751 
1752 	for (i = from_phy; i < ex->num_phys; i++) {
1753 		int phy_change_count = 0;
1754 
1755 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1756 		switch (res) {
1757 		case SMP_RESP_PHY_VACANT:
1758 		case SMP_RESP_NO_PHY:
1759 			continue;
1760 		case SMP_RESP_FUNC_ACC:
1761 			break;
1762 		default:
1763 			return res;
1764 		}
1765 
1766 		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1767 			if (update)
1768 				ex->ex_phy[i].phy_change_count =
1769 					phy_change_count;
1770 			*phy_id = i;
1771 			return 0;
1772 		}
1773 	}
1774 	return 0;
1775 }
1776 
1777 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1778 {
1779 	int res;
1780 	u8  *rg_req;
1781 	struct smp_resp  *rg_resp;
1782 
1783 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1784 	if (!rg_req)
1785 		return -ENOMEM;
1786 
1787 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1788 	if (!rg_resp) {
1789 		kfree(rg_req);
1790 		return -ENOMEM;
1791 	}
1792 
1793 	rg_req[1] = SMP_REPORT_GENERAL;
1794 
1795 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1796 			       RG_RESP_SIZE);
1797 	if (res)
1798 		goto out;
1799 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1800 		res = rg_resp->result;
1801 		goto out;
1802 	}
1803 
1804 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1805 out:
1806 	kfree(rg_resp);
1807 	kfree(rg_req);
1808 	return res;
1809 }
1810 /**
1811  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1812  * @dev:domain device to be detect.
1813  * @src_dev: the device which originated BROADCAST(CHANGE).
1814  *
1815  * Add self-configuration expander support. Suppose two expander cascading,
1816  * when the first level expander is self-configuring, hotplug the disks in
1817  * second level expander, BROADCAST(CHANGE) will not only be originated
1818  * in the second level expander, but also be originated in the first level
1819  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1820  * expander changed count in two level expanders will all increment at least
1821  * once, but the phy which chang count has changed is the source device which
1822  * we concerned.
1823  */
1824 
1825 static int sas_find_bcast_dev(struct domain_device *dev,
1826 			      struct domain_device **src_dev)
1827 {
1828 	struct expander_device *ex = &dev->ex_dev;
1829 	int ex_change_count = -1;
1830 	int phy_id = -1;
1831 	int res;
1832 	struct domain_device *ch;
1833 
1834 	res = sas_get_ex_change_count(dev, &ex_change_count);
1835 	if (res)
1836 		goto out;
1837 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1838 		/* Just detect if this expander phys phy change count changed,
1839 		* in order to determine if this expander originate BROADCAST,
1840 		* and do not update phy change count field in our structure.
1841 		*/
1842 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1843 		if (phy_id != -1) {
1844 			*src_dev = dev;
1845 			ex->ex_change_count = ex_change_count;
1846 			SAS_DPRINTK("Expander phy change count has changed\n");
1847 			return res;
1848 		} else
1849 			SAS_DPRINTK("Expander phys DID NOT change\n");
1850 	}
1851 	list_for_each_entry(ch, &ex->children, siblings) {
1852 		if (ch->dev_type == SAS_EDGE_EXPANDER_DEVICE || ch->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1853 			res = sas_find_bcast_dev(ch, src_dev);
1854 			if (*src_dev)
1855 				return res;
1856 		}
1857 	}
1858 out:
1859 	return res;
1860 }
1861 
1862 static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
1863 {
1864 	struct expander_device *ex = &dev->ex_dev;
1865 	struct domain_device *child, *n;
1866 
1867 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1868 		set_bit(SAS_DEV_GONE, &child->state);
1869 		if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1870 		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
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 (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1891 				    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
1892 					sas_unregister_ex_tree(parent->port, child);
1893 				else
1894 					sas_unregister_dev(parent->port, child);
1895 				found = child;
1896 				break;
1897 			}
1898 		}
1899 		sas_disable_routing(parent, phy->attached_sas_addr);
1900 	}
1901 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1902 	if (phy->port) {
1903 		sas_port_delete_phy(phy->port, phy->phy);
1904 		sas_device_set_phy(found, phy->port);
1905 		if (phy->port->num_phys == 0)
1906 			sas_port_delete(phy->port);
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 (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1920 		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
1921 			struct sas_expander_device *ex =
1922 				rphy_to_expander_device(child->rphy);
1923 
1924 			if (level > ex->level)
1925 				res = sas_discover_bfs_by_root_level(child,
1926 								     level);
1927 			else if (level == ex->level)
1928 				res = sas_ex_discover_devices(child, -1);
1929 		}
1930 	}
1931 	return res;
1932 }
1933 
1934 static int sas_discover_bfs_by_root(struct domain_device *dev)
1935 {
1936 	int res;
1937 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1938 	int level = ex->level+1;
1939 
1940 	res = sas_ex_discover_devices(dev, -1);
1941 	if (res)
1942 		goto out;
1943 	do {
1944 		res = sas_discover_bfs_by_root_level(dev, level);
1945 		mb();
1946 		level += 1;
1947 	} while (level <= dev->port->disc.max_level);
1948 out:
1949 	return res;
1950 }
1951 
1952 static int sas_discover_new(struct domain_device *dev, int phy_id)
1953 {
1954 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1955 	struct domain_device *child;
1956 	int res;
1957 
1958 	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
1959 		    SAS_ADDR(dev->sas_addr), phy_id);
1960 	res = sas_ex_phy_discover(dev, phy_id);
1961 	if (res)
1962 		return res;
1963 
1964 	if (sas_ex_join_wide_port(dev, phy_id))
1965 		return 0;
1966 
1967 	res = sas_ex_discover_devices(dev, phy_id);
1968 	if (res)
1969 		return res;
1970 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1971 		if (SAS_ADDR(child->sas_addr) ==
1972 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1973 			if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
1974 			    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
1975 				res = sas_discover_bfs_by_root(child);
1976 			break;
1977 		}
1978 	}
1979 	return res;
1980 }
1981 
1982 static bool dev_type_flutter(enum sas_device_type new, enum sas_device_type old)
1983 {
1984 	if (old == new)
1985 		return true;
1986 
1987 	/* treat device directed resets as flutter, if we went
1988 	 * SAS_END_DEVICE to SAS_SATA_PENDING the link needs recovery
1989 	 */
1990 	if ((old == SAS_SATA_PENDING && new == SAS_END_DEVICE) ||
1991 	    (old == SAS_END_DEVICE && new == SAS_SATA_PENDING))
1992 		return true;
1993 
1994 	return false;
1995 }
1996 
1997 static int sas_rediscover_dev(struct domain_device *dev, int phy_id, bool last)
1998 {
1999 	struct expander_device *ex = &dev->ex_dev;
2000 	struct ex_phy *phy = &ex->ex_phy[phy_id];
2001 	enum sas_device_type type = SAS_PHY_UNUSED;
2002 	u8 sas_addr[8];
2003 	int res;
2004 
2005 	memset(sas_addr, 0, 8);
2006 	res = sas_get_phy_attached_dev(dev, phy_id, sas_addr, &type);
2007 	switch (res) {
2008 	case SMP_RESP_NO_PHY:
2009 		phy->phy_state = PHY_NOT_PRESENT;
2010 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2011 		return res;
2012 	case SMP_RESP_PHY_VACANT:
2013 		phy->phy_state = PHY_VACANT;
2014 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2015 		return res;
2016 	case SMP_RESP_FUNC_ACC:
2017 		break;
2018 	case -ECOMM:
2019 		break;
2020 	default:
2021 		return res;
2022 	}
2023 
2024 	if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM)) {
2025 		phy->phy_state = PHY_EMPTY;
2026 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2027 		return res;
2028 	} else if (SAS_ADDR(sas_addr) == SAS_ADDR(phy->attached_sas_addr) &&
2029 		   dev_type_flutter(type, phy->attached_dev_type)) {
2030 		struct domain_device *ata_dev = sas_ex_to_ata(dev, phy_id);
2031 		char *action = "";
2032 
2033 		sas_ex_phy_discover(dev, phy_id);
2034 
2035 		if (ata_dev && phy->attached_dev_type == SAS_SATA_PENDING)
2036 			action = ", needs recovery";
2037 		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter%s\n",
2038 			    SAS_ADDR(dev->sas_addr), phy_id, action);
2039 		return res;
2040 	}
2041 
2042 	/* delete the old link */
2043 	if (SAS_ADDR(phy->attached_sas_addr) &&
2044 	    SAS_ADDR(sas_addr) != SAS_ADDR(phy->attached_sas_addr)) {
2045 		SAS_DPRINTK("ex %016llx phy 0x%x replace %016llx\n",
2046 			    SAS_ADDR(dev->sas_addr), phy_id,
2047 			    SAS_ADDR(phy->attached_sas_addr));
2048 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2049 	}
2050 
2051 	return sas_discover_new(dev, phy_id);
2052 }
2053 
2054 /**
2055  * sas_rediscover - revalidate the domain.
2056  * @dev:domain device to be detect.
2057  * @phy_id: the phy id will be detected.
2058  *
2059  * NOTE: this process _must_ quit (return) as soon as any connection
2060  * errors are encountered.  Connection recovery is done elsewhere.
2061  * Discover process only interrogates devices in order to discover the
2062  * domain.For plugging out, we un-register the device only when it is
2063  * the last phy in the port, for other phys in this port, we just delete it
2064  * from the port.For inserting, we do discovery when it is the
2065  * first phy,for other phys in this port, we add it to the port to
2066  * forming the wide-port.
2067  */
2068 static int sas_rediscover(struct domain_device *dev, const int phy_id)
2069 {
2070 	struct expander_device *ex = &dev->ex_dev;
2071 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
2072 	int res = 0;
2073 	int i;
2074 	bool last = true;	/* is this the last phy of the port */
2075 
2076 	SAS_DPRINTK("ex %016llx phy%d originated BROADCAST(CHANGE)\n",
2077 		    SAS_ADDR(dev->sas_addr), phy_id);
2078 
2079 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
2080 		for (i = 0; i < ex->num_phys; i++) {
2081 			struct ex_phy *phy = &ex->ex_phy[i];
2082 
2083 			if (i == phy_id)
2084 				continue;
2085 			if (SAS_ADDR(phy->attached_sas_addr) ==
2086 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
2087 				SAS_DPRINTK("phy%d part of wide port with "
2088 					    "phy%d\n", phy_id, i);
2089 				last = false;
2090 				break;
2091 			}
2092 		}
2093 		res = sas_rediscover_dev(dev, phy_id, last);
2094 	} else
2095 		res = sas_discover_new(dev, phy_id);
2096 	return res;
2097 }
2098 
2099 /**
2100  * sas_revalidate_domain -- revalidate the domain
2101  * @port: port to the domain of interest
2102  *
2103  * NOTE: this process _must_ quit (return) as soon as any connection
2104  * errors are encountered.  Connection recovery is done elsewhere.
2105  * Discover process only interrogates devices in order to discover the
2106  * domain.
2107  */
2108 int sas_ex_revalidate_domain(struct domain_device *port_dev)
2109 {
2110 	int res;
2111 	struct domain_device *dev = NULL;
2112 
2113 	res = sas_find_bcast_dev(port_dev, &dev);
2114 	while (res == 0 && dev) {
2115 		struct expander_device *ex = &dev->ex_dev;
2116 		int i = 0, phy_id;
2117 
2118 		do {
2119 			phy_id = -1;
2120 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
2121 			if (phy_id == -1)
2122 				break;
2123 			res = sas_rediscover(dev, phy_id);
2124 			i = phy_id + 1;
2125 		} while (i < ex->num_phys);
2126 
2127 		dev = NULL;
2128 		res = sas_find_bcast_dev(port_dev, &dev);
2129 	}
2130 	return res;
2131 }
2132 
2133 int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
2134 		    struct request *req)
2135 {
2136 	struct domain_device *dev;
2137 	int ret, type;
2138 	struct request *rsp = req->next_rq;
2139 
2140 	if (!rsp) {
2141 		printk("%s: space for a smp response is missing\n",
2142 		       __func__);
2143 		return -EINVAL;
2144 	}
2145 
2146 	/* no rphy means no smp target support (ie aic94xx host) */
2147 	if (!rphy)
2148 		return sas_smp_host_handler(shost, req, rsp);
2149 
2150 	type = rphy->identify.device_type;
2151 
2152 	if (type != SAS_EDGE_EXPANDER_DEVICE &&
2153 	    type != SAS_FANOUT_EXPANDER_DEVICE) {
2154 		printk("%s: can we send a smp request to a device?\n",
2155 		       __func__);
2156 		return -EINVAL;
2157 	}
2158 
2159 	dev = sas_find_dev_by_rphy(rphy);
2160 	if (!dev) {
2161 		printk("%s: fail to find a domain_device?\n", __func__);
2162 		return -EINVAL;
2163 	}
2164 
2165 	/* do we need to support multiple segments? */
2166 	if (bio_multiple_segments(req->bio) ||
2167 	    bio_multiple_segments(rsp->bio)) {
2168 		printk("%s: multiple segments req %u, rsp %u\n",
2169 		       __func__, blk_rq_bytes(req), blk_rq_bytes(rsp));
2170 		return -EINVAL;
2171 	}
2172 
2173 	ret = smp_execute_task(dev, bio_data(req->bio), blk_rq_bytes(req),
2174 			       bio_data(rsp->bio), blk_rq_bytes(rsp));
2175 	if (ret > 0) {
2176 		/* positive number is the untransferred residual */
2177 		rsp->resid_len = ret;
2178 		req->resid_len = 0;
2179 		ret = 0;
2180 	} else if (ret == 0) {
2181 		rsp->resid_len = 0;
2182 		req->resid_len = 0;
2183 	}
2184 
2185 	return ret;
2186 }
2187