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 
28 #include "sas_internal.h"
29 
30 #include <scsi/scsi_transport.h>
31 #include <scsi/scsi_transport_sas.h>
32 #include "../scsi_sas_internal.h"
33 
34 static int sas_discover_expander(struct domain_device *dev);
35 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
36 static int sas_configure_phy(struct domain_device *dev, int phy_id,
37 			     u8 *sas_addr, int include);
38 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
39 
40 /* ---------- SMP task management ---------- */
41 
42 static void smp_task_timedout(unsigned long _task)
43 {
44 	struct sas_task *task = (void *) _task;
45 	unsigned long flags;
46 
47 	spin_lock_irqsave(&task->task_state_lock, flags);
48 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
49 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
50 	spin_unlock_irqrestore(&task->task_state_lock, flags);
51 
52 	complete(&task->completion);
53 }
54 
55 static void smp_task_done(struct sas_task *task)
56 {
57 	if (!del_timer(&task->timer))
58 		return;
59 	complete(&task->completion);
60 }
61 
62 /* Give it some long enough timeout. In seconds. */
63 #define SMP_TIMEOUT 10
64 
65 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
66 			    void *resp, int resp_size)
67 {
68 	int res, retry;
69 	struct sas_task *task = NULL;
70 	struct sas_internal *i =
71 		to_sas_internal(dev->port->ha->core.shost->transportt);
72 
73 	for (retry = 0; retry < 3; retry++) {
74 		task = sas_alloc_task(GFP_KERNEL);
75 		if (!task)
76 			return -ENOMEM;
77 
78 		task->dev = dev;
79 		task->task_proto = dev->tproto;
80 		sg_init_one(&task->smp_task.smp_req, req, req_size);
81 		sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
82 
83 		task->task_done = smp_task_done;
84 
85 		task->timer.data = (unsigned long) task;
86 		task->timer.function = smp_task_timedout;
87 		task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
88 		add_timer(&task->timer);
89 
90 		res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
91 
92 		if (res) {
93 			del_timer(&task->timer);
94 			SAS_DPRINTK("executing SMP task failed:%d\n", res);
95 			goto ex_err;
96 		}
97 
98 		wait_for_completion(&task->completion);
99 		res = -ECOMM;
100 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
101 			SAS_DPRINTK("smp task timed out or aborted\n");
102 			i->dft->lldd_abort_task(task);
103 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
104 				SAS_DPRINTK("SMP task aborted and not done\n");
105 				goto ex_err;
106 			}
107 		}
108 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
109 		    task->task_status.stat == SAM_GOOD) {
110 			res = 0;
111 			break;
112 		} if (task->task_status.resp == SAS_TASK_COMPLETE &&
113 		      task->task_status.stat == SAS_DATA_UNDERRUN) {
114 			/* no error, but return the number of bytes of
115 			 * underrun */
116 			res = task->task_status.residual;
117 			break;
118 		} if (task->task_status.resp == SAS_TASK_COMPLETE &&
119 		      task->task_status.stat == SAS_DATA_OVERRUN) {
120 			res = -EMSGSIZE;
121 			break;
122 		} else {
123 			SAS_DPRINTK("%s: task to dev %016llx response: 0x%x "
124 				    "status 0x%x\n", __func__,
125 				    SAS_ADDR(dev->sas_addr),
126 				    task->task_status.resp,
127 				    task->task_status.stat);
128 			sas_free_task(task);
129 			task = NULL;
130 		}
131 	}
132 ex_err:
133 	BUG_ON(retry == 3 && task != NULL);
134 	if (task != NULL) {
135 		sas_free_task(task);
136 	}
137 	return res;
138 }
139 
140 /* ---------- Allocations ---------- */
141 
142 static inline void *alloc_smp_req(int size)
143 {
144 	u8 *p = kzalloc(size, GFP_KERNEL);
145 	if (p)
146 		p[0] = SMP_REQUEST;
147 	return p;
148 }
149 
150 static inline void *alloc_smp_resp(int size)
151 {
152 	return kzalloc(size, GFP_KERNEL);
153 }
154 
155 /* ---------- Expander configuration ---------- */
156 
157 static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
158 			   void *disc_resp)
159 {
160 	struct expander_device *ex = &dev->ex_dev;
161 	struct ex_phy *phy = &ex->ex_phy[phy_id];
162 	struct smp_resp *resp = disc_resp;
163 	struct discover_resp *dr = &resp->disc;
164 	struct sas_rphy *rphy = dev->rphy;
165 	int rediscover = (phy->phy != NULL);
166 
167 	if (!rediscover) {
168 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
169 
170 		/* FIXME: error_handling */
171 		BUG_ON(!phy->phy);
172 	}
173 
174 	switch (resp->result) {
175 	case SMP_RESP_PHY_VACANT:
176 		phy->phy_state = PHY_VACANT;
177 		return;
178 	default:
179 		phy->phy_state = PHY_NOT_PRESENT;
180 		return;
181 	case SMP_RESP_FUNC_ACC:
182 		phy->phy_state = PHY_EMPTY; /* do not know yet */
183 		break;
184 	}
185 
186 	phy->phy_id = phy_id;
187 	phy->attached_dev_type = dr->attached_dev_type;
188 	phy->linkrate = dr->linkrate;
189 	phy->attached_sata_host = dr->attached_sata_host;
190 	phy->attached_sata_dev  = dr->attached_sata_dev;
191 	phy->attached_sata_ps   = dr->attached_sata_ps;
192 	phy->attached_iproto = dr->iproto << 1;
193 	phy->attached_tproto = dr->tproto << 1;
194 	memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
195 	phy->attached_phy_id = dr->attached_phy_id;
196 	phy->phy_change_count = dr->change_count;
197 	phy->routing_attr = dr->routing_attr;
198 	phy->virtual = dr->virtual;
199 	phy->last_da_index = -1;
200 
201 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
202 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
203 	phy->phy->identify.phy_identifier = phy_id;
204 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
205 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
206 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
207 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
208 	phy->phy->negotiated_linkrate = phy->linkrate;
209 
210 	if (!rediscover)
211 		sas_phy_add(phy->phy);
212 
213 	SAS_DPRINTK("ex %016llx phy%02d:%c attached: %016llx\n",
214 		    SAS_ADDR(dev->sas_addr), phy->phy_id,
215 		    phy->routing_attr == TABLE_ROUTING ? 'T' :
216 		    phy->routing_attr == DIRECT_ROUTING ? 'D' :
217 		    phy->routing_attr == SUBTRACTIVE_ROUTING ? 'S' : '?',
218 		    SAS_ADDR(phy->attached_sas_addr));
219 
220 	return;
221 }
222 
223 #define DISCOVER_REQ_SIZE  16
224 #define DISCOVER_RESP_SIZE 56
225 
226 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
227 				      u8 *disc_resp, int single)
228 {
229 	int i, res;
230 
231 	disc_req[9] = single;
232 	for (i = 1 ; i < 3; i++) {
233 		struct discover_resp *dr;
234 
235 		res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
236 				       disc_resp, DISCOVER_RESP_SIZE);
237 		if (res)
238 			return res;
239 		/* This is detecting a failure to transmit inital
240 		 * dev to host FIS as described in section G.5 of
241 		 * sas-2 r 04b */
242 		dr = &((struct smp_resp *)disc_resp)->disc;
243 		if (!(dr->attached_dev_type == 0 &&
244 		      dr->attached_sata_dev))
245 			break;
246 		/* In order to generate the dev to host FIS, we
247 		 * send a link reset to the expander port */
248 		sas_smp_phy_control(dev, single, PHY_FUNC_LINK_RESET, NULL);
249 		/* Wait for the reset to trigger the negotiation */
250 		msleep(500);
251 	}
252 	sas_set_ex_phy(dev, single, disc_resp);
253 	return 0;
254 }
255 
256 static int sas_ex_phy_discover(struct domain_device *dev, int single)
257 {
258 	struct expander_device *ex = &dev->ex_dev;
259 	int  res = 0;
260 	u8   *disc_req;
261 	u8   *disc_resp;
262 
263 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
264 	if (!disc_req)
265 		return -ENOMEM;
266 
267 	disc_resp = alloc_smp_req(DISCOVER_RESP_SIZE);
268 	if (!disc_resp) {
269 		kfree(disc_req);
270 		return -ENOMEM;
271 	}
272 
273 	disc_req[1] = SMP_DISCOVER;
274 
275 	if (0 <= single && single < ex->num_phys) {
276 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
277 	} else {
278 		int i;
279 
280 		for (i = 0; i < ex->num_phys; i++) {
281 			res = sas_ex_phy_discover_helper(dev, disc_req,
282 							 disc_resp, i);
283 			if (res)
284 				goto out_err;
285 		}
286 	}
287 out_err:
288 	kfree(disc_resp);
289 	kfree(disc_req);
290 	return res;
291 }
292 
293 static int sas_expander_discover(struct domain_device *dev)
294 {
295 	struct expander_device *ex = &dev->ex_dev;
296 	int res = -ENOMEM;
297 
298 	ex->ex_phy = kzalloc(sizeof(*ex->ex_phy)*ex->num_phys, GFP_KERNEL);
299 	if (!ex->ex_phy)
300 		return -ENOMEM;
301 
302 	res = sas_ex_phy_discover(dev, -1);
303 	if (res)
304 		goto out_err;
305 
306 	return 0;
307  out_err:
308 	kfree(ex->ex_phy);
309 	ex->ex_phy = NULL;
310 	return res;
311 }
312 
313 #define MAX_EXPANDER_PHYS 128
314 
315 static void ex_assign_report_general(struct domain_device *dev,
316 					    struct smp_resp *resp)
317 {
318 	struct report_general_resp *rg = &resp->rg;
319 
320 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
321 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
322 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
323 	dev->ex_dev.conf_route_table = rg->conf_route_table;
324 	dev->ex_dev.configuring = rg->configuring;
325 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
326 }
327 
328 #define RG_REQ_SIZE   8
329 #define RG_RESP_SIZE 32
330 
331 static int sas_ex_general(struct domain_device *dev)
332 {
333 	u8 *rg_req;
334 	struct smp_resp *rg_resp;
335 	int res;
336 	int i;
337 
338 	rg_req = alloc_smp_req(RG_REQ_SIZE);
339 	if (!rg_req)
340 		return -ENOMEM;
341 
342 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
343 	if (!rg_resp) {
344 		kfree(rg_req);
345 		return -ENOMEM;
346 	}
347 
348 	rg_req[1] = SMP_REPORT_GENERAL;
349 
350 	for (i = 0; i < 5; i++) {
351 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
352 				       RG_RESP_SIZE);
353 
354 		if (res) {
355 			SAS_DPRINTK("RG to ex %016llx failed:0x%x\n",
356 				    SAS_ADDR(dev->sas_addr), res);
357 			goto out;
358 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
359 			SAS_DPRINTK("RG:ex %016llx returned SMP result:0x%x\n",
360 				    SAS_ADDR(dev->sas_addr), rg_resp->result);
361 			res = rg_resp->result;
362 			goto out;
363 		}
364 
365 		ex_assign_report_general(dev, rg_resp);
366 
367 		if (dev->ex_dev.configuring) {
368 			SAS_DPRINTK("RG: ex %llx self-configuring...\n",
369 				    SAS_ADDR(dev->sas_addr));
370 			schedule_timeout_interruptible(5*HZ);
371 		} else
372 			break;
373 	}
374 out:
375 	kfree(rg_req);
376 	kfree(rg_resp);
377 	return res;
378 }
379 
380 static void ex_assign_manuf_info(struct domain_device *dev, void
381 					*_mi_resp)
382 {
383 	u8 *mi_resp = _mi_resp;
384 	struct sas_rphy *rphy = dev->rphy;
385 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
386 
387 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
388 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
389 	memcpy(edev->product_rev, mi_resp + 36,
390 	       SAS_EXPANDER_PRODUCT_REV_LEN);
391 
392 	if (mi_resp[8] & 1) {
393 		memcpy(edev->component_vendor_id, mi_resp + 40,
394 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
395 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
396 		edev->component_revision_id = mi_resp[50];
397 	}
398 }
399 
400 #define MI_REQ_SIZE   8
401 #define MI_RESP_SIZE 64
402 
403 static int sas_ex_manuf_info(struct domain_device *dev)
404 {
405 	u8 *mi_req;
406 	u8 *mi_resp;
407 	int res;
408 
409 	mi_req = alloc_smp_req(MI_REQ_SIZE);
410 	if (!mi_req)
411 		return -ENOMEM;
412 
413 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
414 	if (!mi_resp) {
415 		kfree(mi_req);
416 		return -ENOMEM;
417 	}
418 
419 	mi_req[1] = SMP_REPORT_MANUF_INFO;
420 
421 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
422 	if (res) {
423 		SAS_DPRINTK("MI: ex %016llx failed:0x%x\n",
424 			    SAS_ADDR(dev->sas_addr), res);
425 		goto out;
426 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
427 		SAS_DPRINTK("MI ex %016llx returned SMP result:0x%x\n",
428 			    SAS_ADDR(dev->sas_addr), mi_resp[2]);
429 		goto out;
430 	}
431 
432 	ex_assign_manuf_info(dev, mi_resp);
433 out:
434 	kfree(mi_req);
435 	kfree(mi_resp);
436 	return res;
437 }
438 
439 #define PC_REQ_SIZE  44
440 #define PC_RESP_SIZE 8
441 
442 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
443 			enum phy_func phy_func,
444 			struct sas_phy_linkrates *rates)
445 {
446 	u8 *pc_req;
447 	u8 *pc_resp;
448 	int res;
449 
450 	pc_req = alloc_smp_req(PC_REQ_SIZE);
451 	if (!pc_req)
452 		return -ENOMEM;
453 
454 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
455 	if (!pc_resp) {
456 		kfree(pc_req);
457 		return -ENOMEM;
458 	}
459 
460 	pc_req[1] = SMP_PHY_CONTROL;
461 	pc_req[9] = phy_id;
462 	pc_req[10]= phy_func;
463 	if (rates) {
464 		pc_req[32] = rates->minimum_linkrate << 4;
465 		pc_req[33] = rates->maximum_linkrate << 4;
466 	}
467 
468 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
469 
470 	kfree(pc_resp);
471 	kfree(pc_req);
472 	return res;
473 }
474 
475 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
476 {
477 	struct expander_device *ex = &dev->ex_dev;
478 	struct ex_phy *phy = &ex->ex_phy[phy_id];
479 
480 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
481 	phy->linkrate = SAS_PHY_DISABLED;
482 }
483 
484 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
485 {
486 	struct expander_device *ex = &dev->ex_dev;
487 	int i;
488 
489 	for (i = 0; i < ex->num_phys; i++) {
490 		struct ex_phy *phy = &ex->ex_phy[i];
491 
492 		if (phy->phy_state == PHY_VACANT ||
493 		    phy->phy_state == PHY_NOT_PRESENT)
494 			continue;
495 
496 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
497 			sas_ex_disable_phy(dev, i);
498 	}
499 }
500 
501 static int sas_dev_present_in_domain(struct asd_sas_port *port,
502 					    u8 *sas_addr)
503 {
504 	struct domain_device *dev;
505 
506 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
507 		return 1;
508 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
509 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
510 			return 1;
511 	}
512 	return 0;
513 }
514 
515 #define RPEL_REQ_SIZE	16
516 #define RPEL_RESP_SIZE	32
517 int sas_smp_get_phy_events(struct sas_phy *phy)
518 {
519 	int res;
520 	u8 *req;
521 	u8 *resp;
522 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
523 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
524 
525 	req = alloc_smp_req(RPEL_REQ_SIZE);
526 	if (!req)
527 		return -ENOMEM;
528 
529 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
530 	if (!resp) {
531 		kfree(req);
532 		return -ENOMEM;
533 	}
534 
535 	req[1] = SMP_REPORT_PHY_ERR_LOG;
536 	req[9] = phy->number;
537 
538 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
539 			            resp, RPEL_RESP_SIZE);
540 
541 	if (!res)
542 		goto out;
543 
544 	phy->invalid_dword_count = scsi_to_u32(&resp[12]);
545 	phy->running_disparity_error_count = scsi_to_u32(&resp[16]);
546 	phy->loss_of_dword_sync_count = scsi_to_u32(&resp[20]);
547 	phy->phy_reset_problem_count = scsi_to_u32(&resp[24]);
548 
549  out:
550 	kfree(resp);
551 	return res;
552 
553 }
554 
555 #ifdef CONFIG_SCSI_SAS_ATA
556 
557 #define RPS_REQ_SIZE  16
558 #define RPS_RESP_SIZE 60
559 
560 static int sas_get_report_phy_sata(struct domain_device *dev,
561 					  int phy_id,
562 					  struct smp_resp *rps_resp)
563 {
564 	int res;
565 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
566 	u8 *resp = (u8 *)rps_resp;
567 
568 	if (!rps_req)
569 		return -ENOMEM;
570 
571 	rps_req[1] = SMP_REPORT_PHY_SATA;
572 	rps_req[9] = phy_id;
573 
574 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
575 			            rps_resp, RPS_RESP_SIZE);
576 
577 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
578 	 * standards cockup here.  sas-2 explicitly specifies the FIS
579 	 * should be encoded so that FIS type is in resp[24].
580 	 * However, some expanders endian reverse this.  Undo the
581 	 * reversal here */
582 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
583 		int i;
584 
585 		for (i = 0; i < 5; i++) {
586 			int j = 24 + (i*4);
587 			u8 a, b;
588 			a = resp[j + 0];
589 			b = resp[j + 1];
590 			resp[j + 0] = resp[j + 3];
591 			resp[j + 1] = resp[j + 2];
592 			resp[j + 2] = b;
593 			resp[j + 3] = a;
594 		}
595 	}
596 
597 	kfree(rps_req);
598 	return res;
599 }
600 #endif
601 
602 static void sas_ex_get_linkrate(struct domain_device *parent,
603 				       struct domain_device *child,
604 				       struct ex_phy *parent_phy)
605 {
606 	struct expander_device *parent_ex = &parent->ex_dev;
607 	struct sas_port *port;
608 	int i;
609 
610 	child->pathways = 0;
611 
612 	port = parent_phy->port;
613 
614 	for (i = 0; i < parent_ex->num_phys; i++) {
615 		struct ex_phy *phy = &parent_ex->ex_phy[i];
616 
617 		if (phy->phy_state == PHY_VACANT ||
618 		    phy->phy_state == PHY_NOT_PRESENT)
619 			continue;
620 
621 		if (SAS_ADDR(phy->attached_sas_addr) ==
622 		    SAS_ADDR(child->sas_addr)) {
623 
624 			child->min_linkrate = min(parent->min_linkrate,
625 						  phy->linkrate);
626 			child->max_linkrate = max(parent->max_linkrate,
627 						  phy->linkrate);
628 			child->pathways++;
629 			sas_port_add_phy(port, phy->phy);
630 		}
631 	}
632 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
633 	child->pathways = min(child->pathways, parent->pathways);
634 }
635 
636 static struct domain_device *sas_ex_discover_end_dev(
637 	struct domain_device *parent, int phy_id)
638 {
639 	struct expander_device *parent_ex = &parent->ex_dev;
640 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
641 	struct domain_device *child = NULL;
642 	struct sas_rphy *rphy;
643 	int res;
644 
645 	if (phy->attached_sata_host || phy->attached_sata_ps)
646 		return NULL;
647 
648 	child = kzalloc(sizeof(*child), GFP_KERNEL);
649 	if (!child)
650 		return NULL;
651 
652 	child->parent = parent;
653 	child->port   = parent->port;
654 	child->iproto = phy->attached_iproto;
655 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
656 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
657 	if (!phy->port) {
658 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
659 		if (unlikely(!phy->port))
660 			goto out_err;
661 		if (unlikely(sas_port_add(phy->port) != 0)) {
662 			sas_port_free(phy->port);
663 			goto out_err;
664 		}
665 	}
666 	sas_ex_get_linkrate(parent, child, phy);
667 
668 #ifdef CONFIG_SCSI_SAS_ATA
669 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
670 		child->dev_type = SATA_DEV;
671 		if (phy->attached_tproto & SAS_PROTOCOL_STP)
672 			child->tproto = phy->attached_tproto;
673 		if (phy->attached_sata_dev)
674 			child->tproto |= SATA_DEV;
675 		res = sas_get_report_phy_sata(parent, phy_id,
676 					      &child->sata_dev.rps_resp);
677 		if (res) {
678 			SAS_DPRINTK("report phy sata to %016llx:0x%x returned "
679 				    "0x%x\n", SAS_ADDR(parent->sas_addr),
680 				    phy_id, res);
681 			goto out_free;
682 		}
683 		memcpy(child->frame_rcvd, &child->sata_dev.rps_resp.rps.fis,
684 		       sizeof(struct dev_to_host_fis));
685 
686 		rphy = sas_end_device_alloc(phy->port);
687 		if (unlikely(!rphy))
688 			goto out_free;
689 
690 		sas_init_dev(child);
691 
692 		child->rphy = rphy;
693 
694 		spin_lock_irq(&parent->port->dev_list_lock);
695 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
696 		spin_unlock_irq(&parent->port->dev_list_lock);
697 
698 		res = sas_discover_sata(child);
699 		if (res) {
700 			SAS_DPRINTK("sas_discover_sata() for device %16llx at "
701 				    "%016llx:0x%x returned 0x%x\n",
702 				    SAS_ADDR(child->sas_addr),
703 				    SAS_ADDR(parent->sas_addr), phy_id, res);
704 			goto out_list_del;
705 		}
706 	} else
707 #endif
708 	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
709 		child->dev_type = SAS_END_DEV;
710 		rphy = sas_end_device_alloc(phy->port);
711 		/* FIXME: error handling */
712 		if (unlikely(!rphy))
713 			goto out_free;
714 		child->tproto = phy->attached_tproto;
715 		sas_init_dev(child);
716 
717 		child->rphy = rphy;
718 		sas_fill_in_rphy(child, rphy);
719 
720 		spin_lock_irq(&parent->port->dev_list_lock);
721 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
722 		spin_unlock_irq(&parent->port->dev_list_lock);
723 
724 		res = sas_discover_end_dev(child);
725 		if (res) {
726 			SAS_DPRINTK("sas_discover_end_dev() for device %16llx "
727 				    "at %016llx:0x%x returned 0x%x\n",
728 				    SAS_ADDR(child->sas_addr),
729 				    SAS_ADDR(parent->sas_addr), phy_id, res);
730 			goto out_list_del;
731 		}
732 	} else {
733 		SAS_DPRINTK("target proto 0x%x at %016llx:0x%x not handled\n",
734 			    phy->attached_tproto, SAS_ADDR(parent->sas_addr),
735 			    phy_id);
736 		goto out_free;
737 	}
738 
739 	list_add_tail(&child->siblings, &parent_ex->children);
740 	return child;
741 
742  out_list_del:
743 	sas_rphy_free(child->rphy);
744 	child->rphy = NULL;
745 	list_del(&child->dev_list_node);
746  out_free:
747 	sas_port_delete(phy->port);
748  out_err:
749 	phy->port = NULL;
750 	kfree(child);
751 	return NULL;
752 }
753 
754 /* See if this phy is part of a wide port */
755 static int sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
756 {
757 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
758 	int i;
759 
760 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
761 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
762 
763 		if (ephy == phy)
764 			continue;
765 
766 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
767 			    SAS_ADDR_SIZE) && ephy->port) {
768 			sas_port_add_phy(ephy->port, phy->phy);
769 			phy->port = ephy->port;
770 			phy->phy_state = PHY_DEVICE_DISCOVERED;
771 			return 0;
772 		}
773 	}
774 
775 	return -ENODEV;
776 }
777 
778 static struct domain_device *sas_ex_discover_expander(
779 	struct domain_device *parent, int phy_id)
780 {
781 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
782 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
783 	struct domain_device *child = NULL;
784 	struct sas_rphy *rphy;
785 	struct sas_expander_device *edev;
786 	struct asd_sas_port *port;
787 	int res;
788 
789 	if (phy->routing_attr == DIRECT_ROUTING) {
790 		SAS_DPRINTK("ex %016llx:0x%x:D <--> ex %016llx:0x%x is not "
791 			    "allowed\n",
792 			    SAS_ADDR(parent->sas_addr), phy_id,
793 			    SAS_ADDR(phy->attached_sas_addr),
794 			    phy->attached_phy_id);
795 		return NULL;
796 	}
797 	child = kzalloc(sizeof(*child), GFP_KERNEL);
798 	if (!child)
799 		return NULL;
800 
801 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
802 	/* FIXME: better error handling */
803 	BUG_ON(sas_port_add(phy->port) != 0);
804 
805 
806 	switch (phy->attached_dev_type) {
807 	case EDGE_DEV:
808 		rphy = sas_expander_alloc(phy->port,
809 					  SAS_EDGE_EXPANDER_DEVICE);
810 		break;
811 	case FANOUT_DEV:
812 		rphy = sas_expander_alloc(phy->port,
813 					  SAS_FANOUT_EXPANDER_DEVICE);
814 		break;
815 	default:
816 		rphy = NULL;	/* shut gcc up */
817 		BUG();
818 	}
819 	port = parent->port;
820 	child->rphy = rphy;
821 	edev = rphy_to_expander_device(rphy);
822 	child->dev_type = phy->attached_dev_type;
823 	child->parent = parent;
824 	child->port = port;
825 	child->iproto = phy->attached_iproto;
826 	child->tproto = phy->attached_tproto;
827 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
828 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
829 	sas_ex_get_linkrate(parent, child, phy);
830 	edev->level = parent_ex->level + 1;
831 	parent->port->disc.max_level = max(parent->port->disc.max_level,
832 					   edev->level);
833 	sas_init_dev(child);
834 	sas_fill_in_rphy(child, rphy);
835 	sas_rphy_add(rphy);
836 
837 	spin_lock_irq(&parent->port->dev_list_lock);
838 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
839 	spin_unlock_irq(&parent->port->dev_list_lock);
840 
841 	res = sas_discover_expander(child);
842 	if (res) {
843 		kfree(child);
844 		return NULL;
845 	}
846 	list_add_tail(&child->siblings, &parent->ex_dev.children);
847 	return child;
848 }
849 
850 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
851 {
852 	struct expander_device *ex = &dev->ex_dev;
853 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
854 	struct domain_device *child = NULL;
855 	int res = 0;
856 
857 	/* Phy state */
858 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
859 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
860 			res = sas_ex_phy_discover(dev, phy_id);
861 		if (res)
862 			return res;
863 	}
864 
865 	/* Parent and domain coherency */
866 	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
867 			     SAS_ADDR(dev->port->sas_addr))) {
868 		sas_add_parent_port(dev, phy_id);
869 		return 0;
870 	}
871 	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
872 			    SAS_ADDR(dev->parent->sas_addr))) {
873 		sas_add_parent_port(dev, phy_id);
874 		if (ex_phy->routing_attr == TABLE_ROUTING)
875 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
876 		return 0;
877 	}
878 
879 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
880 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
881 
882 	if (ex_phy->attached_dev_type == NO_DEVICE) {
883 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
884 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
885 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
886 		}
887 		return 0;
888 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
889 		return 0;
890 
891 	if (ex_phy->attached_dev_type != SAS_END_DEV &&
892 	    ex_phy->attached_dev_type != FANOUT_DEV &&
893 	    ex_phy->attached_dev_type != EDGE_DEV) {
894 		SAS_DPRINTK("unknown device type(0x%x) attached to ex %016llx "
895 			    "phy 0x%x\n", ex_phy->attached_dev_type,
896 			    SAS_ADDR(dev->sas_addr),
897 			    phy_id);
898 		return 0;
899 	}
900 
901 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
902 	if (res) {
903 		SAS_DPRINTK("configure routing for dev %016llx "
904 			    "reported 0x%x. Forgotten\n",
905 			    SAS_ADDR(ex_phy->attached_sas_addr), res);
906 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
907 		return res;
908 	}
909 
910 	res = sas_ex_join_wide_port(dev, phy_id);
911 	if (!res) {
912 		SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
913 			    phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
914 		return res;
915 	}
916 
917 	switch (ex_phy->attached_dev_type) {
918 	case SAS_END_DEV:
919 		child = sas_ex_discover_end_dev(dev, phy_id);
920 		break;
921 	case FANOUT_DEV:
922 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
923 			SAS_DPRINTK("second fanout expander %016llx phy 0x%x "
924 				    "attached to ex %016llx phy 0x%x\n",
925 				    SAS_ADDR(ex_phy->attached_sas_addr),
926 				    ex_phy->attached_phy_id,
927 				    SAS_ADDR(dev->sas_addr),
928 				    phy_id);
929 			sas_ex_disable_phy(dev, phy_id);
930 			break;
931 		} else
932 			memcpy(dev->port->disc.fanout_sas_addr,
933 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
934 		/* fallthrough */
935 	case EDGE_DEV:
936 		child = sas_ex_discover_expander(dev, phy_id);
937 		break;
938 	default:
939 		break;
940 	}
941 
942 	if (child) {
943 		int i;
944 
945 		for (i = 0; i < ex->num_phys; i++) {
946 			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
947 			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
948 				continue;
949 			/*
950 			 * Due to races, the phy might not get added to the
951 			 * wide port, so we add the phy to the wide port here.
952 			 */
953 			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
954 			    SAS_ADDR(child->sas_addr)) {
955 				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
956 				res = sas_ex_join_wide_port(dev, i);
957 				if (!res)
958 					SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
959 						    i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
960 
961 			}
962 		}
963 		res = 0;
964 	}
965 
966 	return res;
967 }
968 
969 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
970 {
971 	struct expander_device *ex = &dev->ex_dev;
972 	int i;
973 
974 	for (i = 0; i < ex->num_phys; i++) {
975 		struct ex_phy *phy = &ex->ex_phy[i];
976 
977 		if (phy->phy_state == PHY_VACANT ||
978 		    phy->phy_state == PHY_NOT_PRESENT)
979 			continue;
980 
981 		if ((phy->attached_dev_type == EDGE_DEV ||
982 		     phy->attached_dev_type == FANOUT_DEV) &&
983 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
984 
985 			memcpy(sub_addr, phy->attached_sas_addr,SAS_ADDR_SIZE);
986 
987 			return 1;
988 		}
989 	}
990 	return 0;
991 }
992 
993 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
994 {
995 	struct expander_device *ex = &dev->ex_dev;
996 	struct domain_device *child;
997 	u8 sub_addr[8] = {0, };
998 
999 	list_for_each_entry(child, &ex->children, siblings) {
1000 		if (child->dev_type != EDGE_DEV &&
1001 		    child->dev_type != FANOUT_DEV)
1002 			continue;
1003 		if (sub_addr[0] == 0) {
1004 			sas_find_sub_addr(child, sub_addr);
1005 			continue;
1006 		} else {
1007 			u8 s2[8];
1008 
1009 			if (sas_find_sub_addr(child, s2) &&
1010 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1011 
1012 				SAS_DPRINTK("ex %016llx->%016llx-?->%016llx "
1013 					    "diverges from subtractive "
1014 					    "boundary %016llx\n",
1015 					    SAS_ADDR(dev->sas_addr),
1016 					    SAS_ADDR(child->sas_addr),
1017 					    SAS_ADDR(s2),
1018 					    SAS_ADDR(sub_addr));
1019 
1020 				sas_ex_disable_port(child, s2);
1021 			}
1022 		}
1023 	}
1024 	return 0;
1025 }
1026 /**
1027  * sas_ex_discover_devices -- discover devices attached to this expander
1028  * dev: pointer to the expander domain device
1029  * single: if you want to do a single phy, else set to -1;
1030  *
1031  * Configure this expander for use with its devices and register the
1032  * devices of this expander.
1033  */
1034 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1035 {
1036 	struct expander_device *ex = &dev->ex_dev;
1037 	int i = 0, end = ex->num_phys;
1038 	int res = 0;
1039 
1040 	if (0 <= single && single < end) {
1041 		i = single;
1042 		end = i+1;
1043 	}
1044 
1045 	for ( ; i < end; i++) {
1046 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1047 
1048 		if (ex_phy->phy_state == PHY_VACANT ||
1049 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1050 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1051 			continue;
1052 
1053 		switch (ex_phy->linkrate) {
1054 		case SAS_PHY_DISABLED:
1055 		case SAS_PHY_RESET_PROBLEM:
1056 		case SAS_SATA_PORT_SELECTOR:
1057 			continue;
1058 		default:
1059 			res = sas_ex_discover_dev(dev, i);
1060 			if (res)
1061 				break;
1062 			continue;
1063 		}
1064 	}
1065 
1066 	if (!res)
1067 		sas_check_level_subtractive_boundary(dev);
1068 
1069 	return res;
1070 }
1071 
1072 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1073 {
1074 	struct expander_device *ex = &dev->ex_dev;
1075 	int i;
1076 	u8  *sub_sas_addr = NULL;
1077 
1078 	if (dev->dev_type != EDGE_DEV)
1079 		return 0;
1080 
1081 	for (i = 0; i < ex->num_phys; i++) {
1082 		struct ex_phy *phy = &ex->ex_phy[i];
1083 
1084 		if (phy->phy_state == PHY_VACANT ||
1085 		    phy->phy_state == PHY_NOT_PRESENT)
1086 			continue;
1087 
1088 		if ((phy->attached_dev_type == FANOUT_DEV ||
1089 		     phy->attached_dev_type == EDGE_DEV) &&
1090 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1091 
1092 			if (!sub_sas_addr)
1093 				sub_sas_addr = &phy->attached_sas_addr[0];
1094 			else if (SAS_ADDR(sub_sas_addr) !=
1095 				 SAS_ADDR(phy->attached_sas_addr)) {
1096 
1097 				SAS_DPRINTK("ex %016llx phy 0x%x "
1098 					    "diverges(%016llx) on subtractive "
1099 					    "boundary(%016llx). Disabled\n",
1100 					    SAS_ADDR(dev->sas_addr), i,
1101 					    SAS_ADDR(phy->attached_sas_addr),
1102 					    SAS_ADDR(sub_sas_addr));
1103 				sas_ex_disable_phy(dev, i);
1104 			}
1105 		}
1106 	}
1107 	return 0;
1108 }
1109 
1110 static void sas_print_parent_topology_bug(struct domain_device *child,
1111 						 struct ex_phy *parent_phy,
1112 						 struct ex_phy *child_phy)
1113 {
1114 	static const char ra_char[] = {
1115 		[DIRECT_ROUTING] = 'D',
1116 		[SUBTRACTIVE_ROUTING] = 'S',
1117 		[TABLE_ROUTING] = 'T',
1118 	};
1119 	static const char *ex_type[] = {
1120 		[EDGE_DEV] = "edge",
1121 		[FANOUT_DEV] = "fanout",
1122 	};
1123 	struct domain_device *parent = child->parent;
1124 
1125 	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx phy 0x%x "
1126 		   "has %c:%c routing link!\n",
1127 
1128 		   ex_type[parent->dev_type],
1129 		   SAS_ADDR(parent->sas_addr),
1130 		   parent_phy->phy_id,
1131 
1132 		   ex_type[child->dev_type],
1133 		   SAS_ADDR(child->sas_addr),
1134 		   child_phy->phy_id,
1135 
1136 		   ra_char[parent_phy->routing_attr],
1137 		   ra_char[child_phy->routing_attr]);
1138 }
1139 
1140 static int sas_check_eeds(struct domain_device *child,
1141 				 struct ex_phy *parent_phy,
1142 				 struct ex_phy *child_phy)
1143 {
1144 	int res = 0;
1145 	struct domain_device *parent = child->parent;
1146 
1147 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1148 		res = -ENODEV;
1149 		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
1150 			    "phy S:0x%x, while there is a fanout ex %016llx\n",
1151 			    SAS_ADDR(parent->sas_addr),
1152 			    parent_phy->phy_id,
1153 			    SAS_ADDR(child->sas_addr),
1154 			    child_phy->phy_id,
1155 			    SAS_ADDR(parent->port->disc.fanout_sas_addr));
1156 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1157 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1158 		       SAS_ADDR_SIZE);
1159 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1160 		       SAS_ADDR_SIZE);
1161 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1162 		    SAS_ADDR(parent->sas_addr)) ||
1163 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1164 		    SAS_ADDR(child->sas_addr)))
1165 		   &&
1166 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1167 		     SAS_ADDR(parent->sas_addr)) ||
1168 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1169 		     SAS_ADDR(child->sas_addr))))
1170 		;
1171 	else {
1172 		res = -ENODEV;
1173 		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
1174 			    "phy 0x%x link forms a third EEDS!\n",
1175 			    SAS_ADDR(parent->sas_addr),
1176 			    parent_phy->phy_id,
1177 			    SAS_ADDR(child->sas_addr),
1178 			    child_phy->phy_id);
1179 	}
1180 
1181 	return res;
1182 }
1183 
1184 /* Here we spill over 80 columns.  It is intentional.
1185  */
1186 static int sas_check_parent_topology(struct domain_device *child)
1187 {
1188 	struct expander_device *child_ex = &child->ex_dev;
1189 	struct expander_device *parent_ex;
1190 	int i;
1191 	int res = 0;
1192 
1193 	if (!child->parent)
1194 		return 0;
1195 
1196 	if (child->parent->dev_type != EDGE_DEV &&
1197 	    child->parent->dev_type != FANOUT_DEV)
1198 		return 0;
1199 
1200 	parent_ex = &child->parent->ex_dev;
1201 
1202 	for (i = 0; i < parent_ex->num_phys; i++) {
1203 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1204 		struct ex_phy *child_phy;
1205 
1206 		if (parent_phy->phy_state == PHY_VACANT ||
1207 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1208 			continue;
1209 
1210 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1211 			continue;
1212 
1213 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1214 
1215 		switch (child->parent->dev_type) {
1216 		case EDGE_DEV:
1217 			if (child->dev_type == FANOUT_DEV) {
1218 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1219 				    child_phy->routing_attr != TABLE_ROUTING) {
1220 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1221 					res = -ENODEV;
1222 				}
1223 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1224 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1225 					res = sas_check_eeds(child, parent_phy, child_phy);
1226 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1227 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1228 					res = -ENODEV;
1229 				}
1230 			} else if (parent_phy->routing_attr == TABLE_ROUTING &&
1231 				   child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1232 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1233 				res = -ENODEV;
1234 			}
1235 			break;
1236 		case FANOUT_DEV:
1237 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1238 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1239 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1240 				res = -ENODEV;
1241 			}
1242 			break;
1243 		default:
1244 			break;
1245 		}
1246 	}
1247 
1248 	return res;
1249 }
1250 
1251 #define RRI_REQ_SIZE  16
1252 #define RRI_RESP_SIZE 44
1253 
1254 static int sas_configure_present(struct domain_device *dev, int phy_id,
1255 				 u8 *sas_addr, int *index, int *present)
1256 {
1257 	int i, res = 0;
1258 	struct expander_device *ex = &dev->ex_dev;
1259 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1260 	u8 *rri_req;
1261 	u8 *rri_resp;
1262 
1263 	*present = 0;
1264 	*index = 0;
1265 
1266 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1267 	if (!rri_req)
1268 		return -ENOMEM;
1269 
1270 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1271 	if (!rri_resp) {
1272 		kfree(rri_req);
1273 		return -ENOMEM;
1274 	}
1275 
1276 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1277 	rri_req[9] = phy_id;
1278 
1279 	for (i = 0; i < ex->max_route_indexes ; i++) {
1280 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1281 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1282 				       RRI_RESP_SIZE);
1283 		if (res)
1284 			goto out;
1285 		res = rri_resp[2];
1286 		if (res == SMP_RESP_NO_INDEX) {
1287 			SAS_DPRINTK("overflow of indexes: dev %016llx "
1288 				    "phy 0x%x index 0x%x\n",
1289 				    SAS_ADDR(dev->sas_addr), phy_id, i);
1290 			goto out;
1291 		} else if (res != SMP_RESP_FUNC_ACC) {
1292 			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
1293 				    "result 0x%x\n", __func__,
1294 				    SAS_ADDR(dev->sas_addr), phy_id, i, res);
1295 			goto out;
1296 		}
1297 		if (SAS_ADDR(sas_addr) != 0) {
1298 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1299 				*index = i;
1300 				if ((rri_resp[12] & 0x80) == 0x80)
1301 					*present = 0;
1302 				else
1303 					*present = 1;
1304 				goto out;
1305 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1306 				*index = i;
1307 				*present = 0;
1308 				goto out;
1309 			}
1310 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1311 			   phy->last_da_index < i) {
1312 			phy->last_da_index = i;
1313 			*index = i;
1314 			*present = 0;
1315 			goto out;
1316 		}
1317 	}
1318 	res = -1;
1319 out:
1320 	kfree(rri_req);
1321 	kfree(rri_resp);
1322 	return res;
1323 }
1324 
1325 #define CRI_REQ_SIZE  44
1326 #define CRI_RESP_SIZE  8
1327 
1328 static int sas_configure_set(struct domain_device *dev, int phy_id,
1329 			     u8 *sas_addr, int index, int include)
1330 {
1331 	int res;
1332 	u8 *cri_req;
1333 	u8 *cri_resp;
1334 
1335 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1336 	if (!cri_req)
1337 		return -ENOMEM;
1338 
1339 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1340 	if (!cri_resp) {
1341 		kfree(cri_req);
1342 		return -ENOMEM;
1343 	}
1344 
1345 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1346 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1347 	cri_req[9] = phy_id;
1348 	if (SAS_ADDR(sas_addr) == 0 || !include)
1349 		cri_req[12] |= 0x80;
1350 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1351 
1352 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1353 			       CRI_RESP_SIZE);
1354 	if (res)
1355 		goto out;
1356 	res = cri_resp[2];
1357 	if (res == SMP_RESP_NO_INDEX) {
1358 		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
1359 			    "index 0x%x\n",
1360 			    SAS_ADDR(dev->sas_addr), phy_id, index);
1361 	}
1362 out:
1363 	kfree(cri_req);
1364 	kfree(cri_resp);
1365 	return res;
1366 }
1367 
1368 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1369 				    u8 *sas_addr, int include)
1370 {
1371 	int index;
1372 	int present;
1373 	int res;
1374 
1375 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1376 	if (res)
1377 		return res;
1378 	if (include ^ present)
1379 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1380 
1381 	return res;
1382 }
1383 
1384 /**
1385  * sas_configure_parent -- configure routing table of parent
1386  * parent: parent expander
1387  * child: child expander
1388  * sas_addr: SAS port identifier of device directly attached to child
1389  */
1390 static int sas_configure_parent(struct domain_device *parent,
1391 				struct domain_device *child,
1392 				u8 *sas_addr, int include)
1393 {
1394 	struct expander_device *ex_parent = &parent->ex_dev;
1395 	int res = 0;
1396 	int i;
1397 
1398 	if (parent->parent) {
1399 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1400 					   include);
1401 		if (res)
1402 			return res;
1403 	}
1404 
1405 	if (ex_parent->conf_route_table == 0) {
1406 		SAS_DPRINTK("ex %016llx has self-configuring routing table\n",
1407 			    SAS_ADDR(parent->sas_addr));
1408 		return 0;
1409 	}
1410 
1411 	for (i = 0; i < ex_parent->num_phys; i++) {
1412 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1413 
1414 		if ((phy->routing_attr == TABLE_ROUTING) &&
1415 		    (SAS_ADDR(phy->attached_sas_addr) ==
1416 		     SAS_ADDR(child->sas_addr))) {
1417 			res = sas_configure_phy(parent, i, sas_addr, include);
1418 			if (res)
1419 				return res;
1420 		}
1421 	}
1422 
1423 	return res;
1424 }
1425 
1426 /**
1427  * sas_configure_routing -- configure routing
1428  * dev: expander device
1429  * sas_addr: port identifier of device directly attached to the expander device
1430  */
1431 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1432 {
1433 	if (dev->parent)
1434 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1435 	return 0;
1436 }
1437 
1438 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1439 {
1440 	if (dev->parent)
1441 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1442 	return 0;
1443 }
1444 
1445 /**
1446  * sas_discover_expander -- expander discovery
1447  * @ex: pointer to expander domain device
1448  *
1449  * See comment in sas_discover_sata().
1450  */
1451 static int sas_discover_expander(struct domain_device *dev)
1452 {
1453 	int res;
1454 
1455 	res = sas_notify_lldd_dev_found(dev);
1456 	if (res)
1457 		return res;
1458 
1459 	res = sas_ex_general(dev);
1460 	if (res)
1461 		goto out_err;
1462 	res = sas_ex_manuf_info(dev);
1463 	if (res)
1464 		goto out_err;
1465 
1466 	res = sas_expander_discover(dev);
1467 	if (res) {
1468 		SAS_DPRINTK("expander %016llx discovery failed(0x%x)\n",
1469 			    SAS_ADDR(dev->sas_addr), res);
1470 		goto out_err;
1471 	}
1472 
1473 	sas_check_ex_subtractive_boundary(dev);
1474 	res = sas_check_parent_topology(dev);
1475 	if (res)
1476 		goto out_err;
1477 	return 0;
1478 out_err:
1479 	sas_notify_lldd_dev_gone(dev);
1480 	return res;
1481 }
1482 
1483 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1484 {
1485 	int res = 0;
1486 	struct domain_device *dev;
1487 
1488 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1489 		if (dev->dev_type == EDGE_DEV ||
1490 		    dev->dev_type == FANOUT_DEV) {
1491 			struct sas_expander_device *ex =
1492 				rphy_to_expander_device(dev->rphy);
1493 
1494 			if (level == ex->level)
1495 				res = sas_ex_discover_devices(dev, -1);
1496 			else if (level > 0)
1497 				res = sas_ex_discover_devices(port->port_dev, -1);
1498 
1499 		}
1500 	}
1501 
1502 	return res;
1503 }
1504 
1505 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1506 {
1507 	int res;
1508 	int level;
1509 
1510 	do {
1511 		level = port->disc.max_level;
1512 		res = sas_ex_level_discovery(port, level);
1513 		mb();
1514 	} while (level < port->disc.max_level);
1515 
1516 	return res;
1517 }
1518 
1519 int sas_discover_root_expander(struct domain_device *dev)
1520 {
1521 	int res;
1522 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1523 
1524 	res = sas_rphy_add(dev->rphy);
1525 	if (res)
1526 		goto out_err;
1527 
1528 	ex->level = dev->port->disc.max_level; /* 0 */
1529 	res = sas_discover_expander(dev);
1530 	if (res)
1531 		goto out_err2;
1532 
1533 	sas_ex_bfs_disc(dev->port);
1534 
1535 	return res;
1536 
1537 out_err2:
1538 	sas_rphy_remove(dev->rphy);
1539 out_err:
1540 	return res;
1541 }
1542 
1543 /* ---------- Domain revalidation ---------- */
1544 
1545 static int sas_get_phy_discover(struct domain_device *dev,
1546 				int phy_id, struct smp_resp *disc_resp)
1547 {
1548 	int res;
1549 	u8 *disc_req;
1550 
1551 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1552 	if (!disc_req)
1553 		return -ENOMEM;
1554 
1555 	disc_req[1] = SMP_DISCOVER;
1556 	disc_req[9] = phy_id;
1557 
1558 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1559 			       disc_resp, DISCOVER_RESP_SIZE);
1560 	if (res)
1561 		goto out;
1562 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1563 		res = disc_resp->result;
1564 		goto out;
1565 	}
1566 out:
1567 	kfree(disc_req);
1568 	return res;
1569 }
1570 
1571 static int sas_get_phy_change_count(struct domain_device *dev,
1572 				    int phy_id, int *pcc)
1573 {
1574 	int res;
1575 	struct smp_resp *disc_resp;
1576 
1577 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1578 	if (!disc_resp)
1579 		return -ENOMEM;
1580 
1581 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1582 	if (!res)
1583 		*pcc = disc_resp->disc.change_count;
1584 
1585 	kfree(disc_resp);
1586 	return res;
1587 }
1588 
1589 static int sas_get_phy_attached_sas_addr(struct domain_device *dev,
1590 					 int phy_id, u8 *attached_sas_addr)
1591 {
1592 	int res;
1593 	struct smp_resp *disc_resp;
1594 	struct discover_resp *dr;
1595 
1596 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1597 	if (!disc_resp)
1598 		return -ENOMEM;
1599 	dr = &disc_resp->disc;
1600 
1601 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1602 	if (!res) {
1603 		memcpy(attached_sas_addr,disc_resp->disc.attached_sas_addr,8);
1604 		if (dr->attached_dev_type == 0)
1605 			memset(attached_sas_addr, 0, 8);
1606 	}
1607 	kfree(disc_resp);
1608 	return res;
1609 }
1610 
1611 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1612 			      int from_phy, bool update)
1613 {
1614 	struct expander_device *ex = &dev->ex_dev;
1615 	int res = 0;
1616 	int i;
1617 
1618 	for (i = from_phy; i < ex->num_phys; i++) {
1619 		int phy_change_count = 0;
1620 
1621 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1622 		if (res)
1623 			goto out;
1624 		else if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1625 			if (update)
1626 				ex->ex_phy[i].phy_change_count =
1627 					phy_change_count;
1628 			*phy_id = i;
1629 			return 0;
1630 		}
1631 	}
1632 out:
1633 	return res;
1634 }
1635 
1636 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1637 {
1638 	int res;
1639 	u8  *rg_req;
1640 	struct smp_resp  *rg_resp;
1641 
1642 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1643 	if (!rg_req)
1644 		return -ENOMEM;
1645 
1646 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1647 	if (!rg_resp) {
1648 		kfree(rg_req);
1649 		return -ENOMEM;
1650 	}
1651 
1652 	rg_req[1] = SMP_REPORT_GENERAL;
1653 
1654 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1655 			       RG_RESP_SIZE);
1656 	if (res)
1657 		goto out;
1658 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1659 		res = rg_resp->result;
1660 		goto out;
1661 	}
1662 
1663 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1664 out:
1665 	kfree(rg_resp);
1666 	kfree(rg_req);
1667 	return res;
1668 }
1669 /**
1670  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1671  * @dev:domain device to be detect.
1672  * @src_dev: the device which originated BROADCAST(CHANGE).
1673  *
1674  * Add self-configuration expander suport. Suppose two expander cascading,
1675  * when the first level expander is self-configuring, hotplug the disks in
1676  * second level expander, BROADCAST(CHANGE) will not only be originated
1677  * in the second level expander, but also be originated in the first level
1678  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1679  * expander changed count in two level expanders will all increment at least
1680  * once, but the phy which chang count has changed is the source device which
1681  * we concerned.
1682  */
1683 
1684 static int sas_find_bcast_dev(struct domain_device *dev,
1685 			      struct domain_device **src_dev)
1686 {
1687 	struct expander_device *ex = &dev->ex_dev;
1688 	int ex_change_count = -1;
1689 	int phy_id = -1;
1690 	int res;
1691 	struct domain_device *ch;
1692 
1693 	res = sas_get_ex_change_count(dev, &ex_change_count);
1694 	if (res)
1695 		goto out;
1696 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1697 		/* Just detect if this expander phys phy change count changed,
1698 		* in order to determine if this expander originate BROADCAST,
1699 		* and do not update phy change count field in our structure.
1700 		*/
1701 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1702 		if (phy_id != -1) {
1703 			*src_dev = dev;
1704 			ex->ex_change_count = ex_change_count;
1705 			SAS_DPRINTK("Expander phy change count has changed\n");
1706 			return res;
1707 		} else
1708 			SAS_DPRINTK("Expander phys DID NOT change\n");
1709 	}
1710 	list_for_each_entry(ch, &ex->children, siblings) {
1711 		if (ch->dev_type == EDGE_DEV || ch->dev_type == FANOUT_DEV) {
1712 			res = sas_find_bcast_dev(ch, src_dev);
1713 			if (src_dev)
1714 				return res;
1715 		}
1716 	}
1717 out:
1718 	return res;
1719 }
1720 
1721 static void sas_unregister_ex_tree(struct domain_device *dev)
1722 {
1723 	struct expander_device *ex = &dev->ex_dev;
1724 	struct domain_device *child, *n;
1725 
1726 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1727 		if (child->dev_type == EDGE_DEV ||
1728 		    child->dev_type == FANOUT_DEV)
1729 			sas_unregister_ex_tree(child);
1730 		else
1731 			sas_unregister_dev(child);
1732 	}
1733 	sas_unregister_dev(dev);
1734 }
1735 
1736 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1737 					 int phy_id, bool last)
1738 {
1739 	struct expander_device *ex_dev = &parent->ex_dev;
1740 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1741 	struct domain_device *child, *n;
1742 	if (last) {
1743 		list_for_each_entry_safe(child, n,
1744 			&ex_dev->children, siblings) {
1745 			if (SAS_ADDR(child->sas_addr) ==
1746 			    SAS_ADDR(phy->attached_sas_addr)) {
1747 				if (child->dev_type == EDGE_DEV ||
1748 				    child->dev_type == FANOUT_DEV)
1749 					sas_unregister_ex_tree(child);
1750 				else
1751 					sas_unregister_dev(child);
1752 				break;
1753 			}
1754 		}
1755 		sas_disable_routing(parent, phy->attached_sas_addr);
1756 	}
1757 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1758 	sas_port_delete_phy(phy->port, phy->phy);
1759 	if (phy->port->num_phys == 0)
1760 		sas_port_delete(phy->port);
1761 	phy->port = NULL;
1762 }
1763 
1764 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1765 					  const int level)
1766 {
1767 	struct expander_device *ex_root = &root->ex_dev;
1768 	struct domain_device *child;
1769 	int res = 0;
1770 
1771 	list_for_each_entry(child, &ex_root->children, siblings) {
1772 		if (child->dev_type == EDGE_DEV ||
1773 		    child->dev_type == FANOUT_DEV) {
1774 			struct sas_expander_device *ex =
1775 				rphy_to_expander_device(child->rphy);
1776 
1777 			if (level > ex->level)
1778 				res = sas_discover_bfs_by_root_level(child,
1779 								     level);
1780 			else if (level == ex->level)
1781 				res = sas_ex_discover_devices(child, -1);
1782 		}
1783 	}
1784 	return res;
1785 }
1786 
1787 static int sas_discover_bfs_by_root(struct domain_device *dev)
1788 {
1789 	int res;
1790 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1791 	int level = ex->level+1;
1792 
1793 	res = sas_ex_discover_devices(dev, -1);
1794 	if (res)
1795 		goto out;
1796 	do {
1797 		res = sas_discover_bfs_by_root_level(dev, level);
1798 		mb();
1799 		level += 1;
1800 	} while (level <= dev->port->disc.max_level);
1801 out:
1802 	return res;
1803 }
1804 
1805 static int sas_discover_new(struct domain_device *dev, int phy_id)
1806 {
1807 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1808 	struct domain_device *child;
1809 	bool found = false;
1810 	int res, i;
1811 
1812 	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
1813 		    SAS_ADDR(dev->sas_addr), phy_id);
1814 	res = sas_ex_phy_discover(dev, phy_id);
1815 	if (res)
1816 		goto out;
1817 	/* to support the wide port inserted */
1818 	for (i = 0; i < dev->ex_dev.num_phys; i++) {
1819 		struct ex_phy *ex_phy_temp = &dev->ex_dev.ex_phy[i];
1820 		if (i == phy_id)
1821 			continue;
1822 		if (SAS_ADDR(ex_phy_temp->attached_sas_addr) ==
1823 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1824 			found = true;
1825 			break;
1826 		}
1827 	}
1828 	if (found) {
1829 		sas_ex_join_wide_port(dev, phy_id);
1830 		return 0;
1831 	}
1832 	res = sas_ex_discover_devices(dev, phy_id);
1833 	if (!res)
1834 		goto out;
1835 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1836 		if (SAS_ADDR(child->sas_addr) ==
1837 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1838 			if (child->dev_type == EDGE_DEV ||
1839 			    child->dev_type == FANOUT_DEV)
1840 				res = sas_discover_bfs_by_root(child);
1841 			break;
1842 		}
1843 	}
1844 out:
1845 	return res;
1846 }
1847 
1848 static int sas_rediscover_dev(struct domain_device *dev, int phy_id, bool last)
1849 {
1850 	struct expander_device *ex = &dev->ex_dev;
1851 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1852 	u8 attached_sas_addr[8];
1853 	int res;
1854 
1855 	res = sas_get_phy_attached_sas_addr(dev, phy_id, attached_sas_addr);
1856 	switch (res) {
1857 	case SMP_RESP_NO_PHY:
1858 		phy->phy_state = PHY_NOT_PRESENT;
1859 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1860 		goto out; break;
1861 	case SMP_RESP_PHY_VACANT:
1862 		phy->phy_state = PHY_VACANT;
1863 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1864 		goto out; break;
1865 	case SMP_RESP_FUNC_ACC:
1866 		break;
1867 	}
1868 
1869 	if (SAS_ADDR(attached_sas_addr) == 0) {
1870 		phy->phy_state = PHY_EMPTY;
1871 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1872 	} else if (SAS_ADDR(attached_sas_addr) ==
1873 		   SAS_ADDR(phy->attached_sas_addr)) {
1874 		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter\n",
1875 			    SAS_ADDR(dev->sas_addr), phy_id);
1876 		sas_ex_phy_discover(dev, phy_id);
1877 	} else
1878 		res = sas_discover_new(dev, phy_id);
1879 out:
1880 	return res;
1881 }
1882 
1883 /**
1884  * sas_rediscover - revalidate the domain.
1885  * @dev:domain device to be detect.
1886  * @phy_id: the phy id will be detected.
1887  *
1888  * NOTE: this process _must_ quit (return) as soon as any connection
1889  * errors are encountered.  Connection recovery is done elsewhere.
1890  * Discover process only interrogates devices in order to discover the
1891  * domain.For plugging out, we un-register the device only when it is
1892  * the last phy in the port, for other phys in this port, we just delete it
1893  * from the port.For inserting, we do discovery when it is the
1894  * first phy,for other phys in this port, we add it to the port to
1895  * forming the wide-port.
1896  */
1897 static int sas_rediscover(struct domain_device *dev, const int phy_id)
1898 {
1899 	struct expander_device *ex = &dev->ex_dev;
1900 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
1901 	int res = 0;
1902 	int i;
1903 	bool last = true;	/* is this the last phy of the port */
1904 
1905 	SAS_DPRINTK("ex %016llx phy%d originated BROADCAST(CHANGE)\n",
1906 		    SAS_ADDR(dev->sas_addr), phy_id);
1907 
1908 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
1909 		for (i = 0; i < ex->num_phys; i++) {
1910 			struct ex_phy *phy = &ex->ex_phy[i];
1911 
1912 			if (i == phy_id)
1913 				continue;
1914 			if (SAS_ADDR(phy->attached_sas_addr) ==
1915 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
1916 				SAS_DPRINTK("phy%d part of wide port with "
1917 					    "phy%d\n", phy_id, i);
1918 				last = false;
1919 				break;
1920 			}
1921 		}
1922 		res = sas_rediscover_dev(dev, phy_id, last);
1923 	} else
1924 		res = sas_discover_new(dev, phy_id);
1925 	return res;
1926 }
1927 
1928 /**
1929  * sas_revalidate_domain -- revalidate the domain
1930  * @port: port to the domain of interest
1931  *
1932  * NOTE: this process _must_ quit (return) as soon as any connection
1933  * errors are encountered.  Connection recovery is done elsewhere.
1934  * Discover process only interrogates devices in order to discover the
1935  * domain.
1936  */
1937 int sas_ex_revalidate_domain(struct domain_device *port_dev)
1938 {
1939 	int res;
1940 	struct domain_device *dev = NULL;
1941 
1942 	res = sas_find_bcast_dev(port_dev, &dev);
1943 	if (res)
1944 		goto out;
1945 	if (dev) {
1946 		struct expander_device *ex = &dev->ex_dev;
1947 		int i = 0, phy_id;
1948 
1949 		do {
1950 			phy_id = -1;
1951 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
1952 			if (phy_id == -1)
1953 				break;
1954 			res = sas_rediscover(dev, phy_id);
1955 			i = phy_id + 1;
1956 		} while (i < ex->num_phys);
1957 	}
1958 out:
1959 	return res;
1960 }
1961 
1962 int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
1963 		    struct request *req)
1964 {
1965 	struct domain_device *dev;
1966 	int ret, type;
1967 	struct request *rsp = req->next_rq;
1968 
1969 	if (!rsp) {
1970 		printk("%s: space for a smp response is missing\n",
1971 		       __func__);
1972 		return -EINVAL;
1973 	}
1974 
1975 	/* no rphy means no smp target support (ie aic94xx host) */
1976 	if (!rphy)
1977 		return sas_smp_host_handler(shost, req, rsp);
1978 
1979 	type = rphy->identify.device_type;
1980 
1981 	if (type != SAS_EDGE_EXPANDER_DEVICE &&
1982 	    type != SAS_FANOUT_EXPANDER_DEVICE) {
1983 		printk("%s: can we send a smp request to a device?\n",
1984 		       __func__);
1985 		return -EINVAL;
1986 	}
1987 
1988 	dev = sas_find_dev_by_rphy(rphy);
1989 	if (!dev) {
1990 		printk("%s: fail to find a domain_device?\n", __func__);
1991 		return -EINVAL;
1992 	}
1993 
1994 	/* do we need to support multiple segments? */
1995 	if (req->bio->bi_vcnt > 1 || rsp->bio->bi_vcnt > 1) {
1996 		printk("%s: multiple segments req %u %u, rsp %u %u\n",
1997 		       __func__, req->bio->bi_vcnt, blk_rq_bytes(req),
1998 		       rsp->bio->bi_vcnt, blk_rq_bytes(rsp));
1999 		return -EINVAL;
2000 	}
2001 
2002 	ret = smp_execute_task(dev, bio_data(req->bio), blk_rq_bytes(req),
2003 			       bio_data(rsp->bio), blk_rq_bytes(rsp));
2004 	if (ret > 0) {
2005 		/* positive number is the untransferred residual */
2006 		rsp->resid_len = ret;
2007 		req->resid_len = 0;
2008 		ret = 0;
2009 	} else if (ret == 0) {
2010 		rsp->resid_len = 0;
2011 		req->resid_len = 0;
2012 	}
2013 
2014 	return ret;
2015 }
2016