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 	}
964 
965 	return res;
966 }
967 
968 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
969 {
970 	struct expander_device *ex = &dev->ex_dev;
971 	int i;
972 
973 	for (i = 0; i < ex->num_phys; i++) {
974 		struct ex_phy *phy = &ex->ex_phy[i];
975 
976 		if (phy->phy_state == PHY_VACANT ||
977 		    phy->phy_state == PHY_NOT_PRESENT)
978 			continue;
979 
980 		if ((phy->attached_dev_type == EDGE_DEV ||
981 		     phy->attached_dev_type == FANOUT_DEV) &&
982 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
983 
984 			memcpy(sub_addr, phy->attached_sas_addr,SAS_ADDR_SIZE);
985 
986 			return 1;
987 		}
988 	}
989 	return 0;
990 }
991 
992 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
993 {
994 	struct expander_device *ex = &dev->ex_dev;
995 	struct domain_device *child;
996 	u8 sub_addr[8] = {0, };
997 
998 	list_for_each_entry(child, &ex->children, siblings) {
999 		if (child->dev_type != EDGE_DEV &&
1000 		    child->dev_type != FANOUT_DEV)
1001 			continue;
1002 		if (sub_addr[0] == 0) {
1003 			sas_find_sub_addr(child, sub_addr);
1004 			continue;
1005 		} else {
1006 			u8 s2[8];
1007 
1008 			if (sas_find_sub_addr(child, s2) &&
1009 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1010 
1011 				SAS_DPRINTK("ex %016llx->%016llx-?->%016llx "
1012 					    "diverges from subtractive "
1013 					    "boundary %016llx\n",
1014 					    SAS_ADDR(dev->sas_addr),
1015 					    SAS_ADDR(child->sas_addr),
1016 					    SAS_ADDR(s2),
1017 					    SAS_ADDR(sub_addr));
1018 
1019 				sas_ex_disable_port(child, s2);
1020 			}
1021 		}
1022 	}
1023 	return 0;
1024 }
1025 /**
1026  * sas_ex_discover_devices -- discover devices attached to this expander
1027  * dev: pointer to the expander domain device
1028  * single: if you want to do a single phy, else set to -1;
1029  *
1030  * Configure this expander for use with its devices and register the
1031  * devices of this expander.
1032  */
1033 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1034 {
1035 	struct expander_device *ex = &dev->ex_dev;
1036 	int i = 0, end = ex->num_phys;
1037 	int res = 0;
1038 
1039 	if (0 <= single && single < end) {
1040 		i = single;
1041 		end = i+1;
1042 	}
1043 
1044 	for ( ; i < end; i++) {
1045 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1046 
1047 		if (ex_phy->phy_state == PHY_VACANT ||
1048 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1049 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1050 			continue;
1051 
1052 		switch (ex_phy->linkrate) {
1053 		case SAS_PHY_DISABLED:
1054 		case SAS_PHY_RESET_PROBLEM:
1055 		case SAS_SATA_PORT_SELECTOR:
1056 			continue;
1057 		default:
1058 			res = sas_ex_discover_dev(dev, i);
1059 			if (res)
1060 				break;
1061 			continue;
1062 		}
1063 	}
1064 
1065 	if (!res)
1066 		sas_check_level_subtractive_boundary(dev);
1067 
1068 	return res;
1069 }
1070 
1071 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1072 {
1073 	struct expander_device *ex = &dev->ex_dev;
1074 	int i;
1075 	u8  *sub_sas_addr = NULL;
1076 
1077 	if (dev->dev_type != EDGE_DEV)
1078 		return 0;
1079 
1080 	for (i = 0; i < ex->num_phys; i++) {
1081 		struct ex_phy *phy = &ex->ex_phy[i];
1082 
1083 		if (phy->phy_state == PHY_VACANT ||
1084 		    phy->phy_state == PHY_NOT_PRESENT)
1085 			continue;
1086 
1087 		if ((phy->attached_dev_type == FANOUT_DEV ||
1088 		     phy->attached_dev_type == EDGE_DEV) &&
1089 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1090 
1091 			if (!sub_sas_addr)
1092 				sub_sas_addr = &phy->attached_sas_addr[0];
1093 			else if (SAS_ADDR(sub_sas_addr) !=
1094 				 SAS_ADDR(phy->attached_sas_addr)) {
1095 
1096 				SAS_DPRINTK("ex %016llx phy 0x%x "
1097 					    "diverges(%016llx) on subtractive "
1098 					    "boundary(%016llx). Disabled\n",
1099 					    SAS_ADDR(dev->sas_addr), i,
1100 					    SAS_ADDR(phy->attached_sas_addr),
1101 					    SAS_ADDR(sub_sas_addr));
1102 				sas_ex_disable_phy(dev, i);
1103 			}
1104 		}
1105 	}
1106 	return 0;
1107 }
1108 
1109 static void sas_print_parent_topology_bug(struct domain_device *child,
1110 						 struct ex_phy *parent_phy,
1111 						 struct ex_phy *child_phy)
1112 {
1113 	static const char ra_char[] = {
1114 		[DIRECT_ROUTING] = 'D',
1115 		[SUBTRACTIVE_ROUTING] = 'S',
1116 		[TABLE_ROUTING] = 'T',
1117 	};
1118 	static const char *ex_type[] = {
1119 		[EDGE_DEV] = "edge",
1120 		[FANOUT_DEV] = "fanout",
1121 	};
1122 	struct domain_device *parent = child->parent;
1123 
1124 	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx phy 0x%x "
1125 		   "has %c:%c routing link!\n",
1126 
1127 		   ex_type[parent->dev_type],
1128 		   SAS_ADDR(parent->sas_addr),
1129 		   parent_phy->phy_id,
1130 
1131 		   ex_type[child->dev_type],
1132 		   SAS_ADDR(child->sas_addr),
1133 		   child_phy->phy_id,
1134 
1135 		   ra_char[parent_phy->routing_attr],
1136 		   ra_char[child_phy->routing_attr]);
1137 }
1138 
1139 static int sas_check_eeds(struct domain_device *child,
1140 				 struct ex_phy *parent_phy,
1141 				 struct ex_phy *child_phy)
1142 {
1143 	int res = 0;
1144 	struct domain_device *parent = child->parent;
1145 
1146 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1147 		res = -ENODEV;
1148 		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
1149 			    "phy S:0x%x, while there is a fanout ex %016llx\n",
1150 			    SAS_ADDR(parent->sas_addr),
1151 			    parent_phy->phy_id,
1152 			    SAS_ADDR(child->sas_addr),
1153 			    child_phy->phy_id,
1154 			    SAS_ADDR(parent->port->disc.fanout_sas_addr));
1155 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1156 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1157 		       SAS_ADDR_SIZE);
1158 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1159 		       SAS_ADDR_SIZE);
1160 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1161 		    SAS_ADDR(parent->sas_addr)) ||
1162 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1163 		    SAS_ADDR(child->sas_addr)))
1164 		   &&
1165 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1166 		     SAS_ADDR(parent->sas_addr)) ||
1167 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1168 		     SAS_ADDR(child->sas_addr))))
1169 		;
1170 	else {
1171 		res = -ENODEV;
1172 		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
1173 			    "phy 0x%x link forms a third EEDS!\n",
1174 			    SAS_ADDR(parent->sas_addr),
1175 			    parent_phy->phy_id,
1176 			    SAS_ADDR(child->sas_addr),
1177 			    child_phy->phy_id);
1178 	}
1179 
1180 	return res;
1181 }
1182 
1183 /* Here we spill over 80 columns.  It is intentional.
1184  */
1185 static int sas_check_parent_topology(struct domain_device *child)
1186 {
1187 	struct expander_device *child_ex = &child->ex_dev;
1188 	struct expander_device *parent_ex;
1189 	int i;
1190 	int res = 0;
1191 
1192 	if (!child->parent)
1193 		return 0;
1194 
1195 	if (child->parent->dev_type != EDGE_DEV &&
1196 	    child->parent->dev_type != FANOUT_DEV)
1197 		return 0;
1198 
1199 	parent_ex = &child->parent->ex_dev;
1200 
1201 	for (i = 0; i < parent_ex->num_phys; i++) {
1202 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1203 		struct ex_phy *child_phy;
1204 
1205 		if (parent_phy->phy_state == PHY_VACANT ||
1206 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1207 			continue;
1208 
1209 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1210 			continue;
1211 
1212 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1213 
1214 		switch (child->parent->dev_type) {
1215 		case EDGE_DEV:
1216 			if (child->dev_type == FANOUT_DEV) {
1217 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1218 				    child_phy->routing_attr != TABLE_ROUTING) {
1219 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1220 					res = -ENODEV;
1221 				}
1222 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1223 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1224 					res = sas_check_eeds(child, parent_phy, child_phy);
1225 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1226 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1227 					res = -ENODEV;
1228 				}
1229 			} else if (parent_phy->routing_attr == TABLE_ROUTING &&
1230 				   child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1231 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1232 				res = -ENODEV;
1233 			}
1234 			break;
1235 		case FANOUT_DEV:
1236 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1237 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1238 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1239 				res = -ENODEV;
1240 			}
1241 			break;
1242 		default:
1243 			break;
1244 		}
1245 	}
1246 
1247 	return res;
1248 }
1249 
1250 #define RRI_REQ_SIZE  16
1251 #define RRI_RESP_SIZE 44
1252 
1253 static int sas_configure_present(struct domain_device *dev, int phy_id,
1254 				 u8 *sas_addr, int *index, int *present)
1255 {
1256 	int i, res = 0;
1257 	struct expander_device *ex = &dev->ex_dev;
1258 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1259 	u8 *rri_req;
1260 	u8 *rri_resp;
1261 
1262 	*present = 0;
1263 	*index = 0;
1264 
1265 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1266 	if (!rri_req)
1267 		return -ENOMEM;
1268 
1269 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1270 	if (!rri_resp) {
1271 		kfree(rri_req);
1272 		return -ENOMEM;
1273 	}
1274 
1275 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1276 	rri_req[9] = phy_id;
1277 
1278 	for (i = 0; i < ex->max_route_indexes ; i++) {
1279 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1280 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1281 				       RRI_RESP_SIZE);
1282 		if (res)
1283 			goto out;
1284 		res = rri_resp[2];
1285 		if (res == SMP_RESP_NO_INDEX) {
1286 			SAS_DPRINTK("overflow of indexes: dev %016llx "
1287 				    "phy 0x%x index 0x%x\n",
1288 				    SAS_ADDR(dev->sas_addr), phy_id, i);
1289 			goto out;
1290 		} else if (res != SMP_RESP_FUNC_ACC) {
1291 			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
1292 				    "result 0x%x\n", __func__,
1293 				    SAS_ADDR(dev->sas_addr), phy_id, i, res);
1294 			goto out;
1295 		}
1296 		if (SAS_ADDR(sas_addr) != 0) {
1297 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1298 				*index = i;
1299 				if ((rri_resp[12] & 0x80) == 0x80)
1300 					*present = 0;
1301 				else
1302 					*present = 1;
1303 				goto out;
1304 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1305 				*index = i;
1306 				*present = 0;
1307 				goto out;
1308 			}
1309 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1310 			   phy->last_da_index < i) {
1311 			phy->last_da_index = i;
1312 			*index = i;
1313 			*present = 0;
1314 			goto out;
1315 		}
1316 	}
1317 	res = -1;
1318 out:
1319 	kfree(rri_req);
1320 	kfree(rri_resp);
1321 	return res;
1322 }
1323 
1324 #define CRI_REQ_SIZE  44
1325 #define CRI_RESP_SIZE  8
1326 
1327 static int sas_configure_set(struct domain_device *dev, int phy_id,
1328 			     u8 *sas_addr, int index, int include)
1329 {
1330 	int res;
1331 	u8 *cri_req;
1332 	u8 *cri_resp;
1333 
1334 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1335 	if (!cri_req)
1336 		return -ENOMEM;
1337 
1338 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1339 	if (!cri_resp) {
1340 		kfree(cri_req);
1341 		return -ENOMEM;
1342 	}
1343 
1344 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1345 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1346 	cri_req[9] = phy_id;
1347 	if (SAS_ADDR(sas_addr) == 0 || !include)
1348 		cri_req[12] |= 0x80;
1349 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1350 
1351 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1352 			       CRI_RESP_SIZE);
1353 	if (res)
1354 		goto out;
1355 	res = cri_resp[2];
1356 	if (res == SMP_RESP_NO_INDEX) {
1357 		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
1358 			    "index 0x%x\n",
1359 			    SAS_ADDR(dev->sas_addr), phy_id, index);
1360 	}
1361 out:
1362 	kfree(cri_req);
1363 	kfree(cri_resp);
1364 	return res;
1365 }
1366 
1367 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1368 				    u8 *sas_addr, int include)
1369 {
1370 	int index;
1371 	int present;
1372 	int res;
1373 
1374 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1375 	if (res)
1376 		return res;
1377 	if (include ^ present)
1378 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1379 
1380 	return res;
1381 }
1382 
1383 /**
1384  * sas_configure_parent -- configure routing table of parent
1385  * parent: parent expander
1386  * child: child expander
1387  * sas_addr: SAS port identifier of device directly attached to child
1388  */
1389 static int sas_configure_parent(struct domain_device *parent,
1390 				struct domain_device *child,
1391 				u8 *sas_addr, int include)
1392 {
1393 	struct expander_device *ex_parent = &parent->ex_dev;
1394 	int res = 0;
1395 	int i;
1396 
1397 	if (parent->parent) {
1398 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1399 					   include);
1400 		if (res)
1401 			return res;
1402 	}
1403 
1404 	if (ex_parent->conf_route_table == 0) {
1405 		SAS_DPRINTK("ex %016llx has self-configuring routing table\n",
1406 			    SAS_ADDR(parent->sas_addr));
1407 		return 0;
1408 	}
1409 
1410 	for (i = 0; i < ex_parent->num_phys; i++) {
1411 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1412 
1413 		if ((phy->routing_attr == TABLE_ROUTING) &&
1414 		    (SAS_ADDR(phy->attached_sas_addr) ==
1415 		     SAS_ADDR(child->sas_addr))) {
1416 			res = sas_configure_phy(parent, i, sas_addr, include);
1417 			if (res)
1418 				return res;
1419 		}
1420 	}
1421 
1422 	return res;
1423 }
1424 
1425 /**
1426  * sas_configure_routing -- configure routing
1427  * dev: expander device
1428  * sas_addr: port identifier of device directly attached to the expander device
1429  */
1430 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1431 {
1432 	if (dev->parent)
1433 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1434 	return 0;
1435 }
1436 
1437 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1438 {
1439 	if (dev->parent)
1440 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1441 	return 0;
1442 }
1443 
1444 /**
1445  * sas_discover_expander -- expander discovery
1446  * @ex: pointer to expander domain device
1447  *
1448  * See comment in sas_discover_sata().
1449  */
1450 static int sas_discover_expander(struct domain_device *dev)
1451 {
1452 	int res;
1453 
1454 	res = sas_notify_lldd_dev_found(dev);
1455 	if (res)
1456 		return res;
1457 
1458 	res = sas_ex_general(dev);
1459 	if (res)
1460 		goto out_err;
1461 	res = sas_ex_manuf_info(dev);
1462 	if (res)
1463 		goto out_err;
1464 
1465 	res = sas_expander_discover(dev);
1466 	if (res) {
1467 		SAS_DPRINTK("expander %016llx discovery failed(0x%x)\n",
1468 			    SAS_ADDR(dev->sas_addr), res);
1469 		goto out_err;
1470 	}
1471 
1472 	sas_check_ex_subtractive_boundary(dev);
1473 	res = sas_check_parent_topology(dev);
1474 	if (res)
1475 		goto out_err;
1476 	return 0;
1477 out_err:
1478 	sas_notify_lldd_dev_gone(dev);
1479 	return res;
1480 }
1481 
1482 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1483 {
1484 	int res = 0;
1485 	struct domain_device *dev;
1486 
1487 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1488 		if (dev->dev_type == EDGE_DEV ||
1489 		    dev->dev_type == FANOUT_DEV) {
1490 			struct sas_expander_device *ex =
1491 				rphy_to_expander_device(dev->rphy);
1492 
1493 			if (level == ex->level)
1494 				res = sas_ex_discover_devices(dev, -1);
1495 			else if (level > 0)
1496 				res = sas_ex_discover_devices(port->port_dev, -1);
1497 
1498 		}
1499 	}
1500 
1501 	return res;
1502 }
1503 
1504 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1505 {
1506 	int res;
1507 	int level;
1508 
1509 	do {
1510 		level = port->disc.max_level;
1511 		res = sas_ex_level_discovery(port, level);
1512 		mb();
1513 	} while (level < port->disc.max_level);
1514 
1515 	return res;
1516 }
1517 
1518 int sas_discover_root_expander(struct domain_device *dev)
1519 {
1520 	int res;
1521 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1522 
1523 	res = sas_rphy_add(dev->rphy);
1524 	if (res)
1525 		goto out_err;
1526 
1527 	ex->level = dev->port->disc.max_level; /* 0 */
1528 	res = sas_discover_expander(dev);
1529 	if (res)
1530 		goto out_err2;
1531 
1532 	sas_ex_bfs_disc(dev->port);
1533 
1534 	return res;
1535 
1536 out_err2:
1537 	sas_rphy_remove(dev->rphy);
1538 out_err:
1539 	return res;
1540 }
1541 
1542 /* ---------- Domain revalidation ---------- */
1543 
1544 static int sas_get_phy_discover(struct domain_device *dev,
1545 				int phy_id, struct smp_resp *disc_resp)
1546 {
1547 	int res;
1548 	u8 *disc_req;
1549 
1550 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1551 	if (!disc_req)
1552 		return -ENOMEM;
1553 
1554 	disc_req[1] = SMP_DISCOVER;
1555 	disc_req[9] = phy_id;
1556 
1557 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1558 			       disc_resp, DISCOVER_RESP_SIZE);
1559 	if (res)
1560 		goto out;
1561 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1562 		res = disc_resp->result;
1563 		goto out;
1564 	}
1565 out:
1566 	kfree(disc_req);
1567 	return res;
1568 }
1569 
1570 static int sas_get_phy_change_count(struct domain_device *dev,
1571 				    int phy_id, int *pcc)
1572 {
1573 	int res;
1574 	struct smp_resp *disc_resp;
1575 
1576 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1577 	if (!disc_resp)
1578 		return -ENOMEM;
1579 
1580 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1581 	if (!res)
1582 		*pcc = disc_resp->disc.change_count;
1583 
1584 	kfree(disc_resp);
1585 	return res;
1586 }
1587 
1588 static int sas_get_phy_attached_sas_addr(struct domain_device *dev,
1589 					 int phy_id, u8 *attached_sas_addr)
1590 {
1591 	int res;
1592 	struct smp_resp *disc_resp;
1593 	struct discover_resp *dr;
1594 
1595 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1596 	if (!disc_resp)
1597 		return -ENOMEM;
1598 	dr = &disc_resp->disc;
1599 
1600 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1601 	if (!res) {
1602 		memcpy(attached_sas_addr,disc_resp->disc.attached_sas_addr,8);
1603 		if (dr->attached_dev_type == 0)
1604 			memset(attached_sas_addr, 0, 8);
1605 	}
1606 	kfree(disc_resp);
1607 	return res;
1608 }
1609 
1610 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1611 			      int from_phy, bool update)
1612 {
1613 	struct expander_device *ex = &dev->ex_dev;
1614 	int res = 0;
1615 	int i;
1616 
1617 	for (i = from_phy; i < ex->num_phys; i++) {
1618 		int phy_change_count = 0;
1619 
1620 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1621 		if (res)
1622 			goto out;
1623 		else if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1624 			if (update)
1625 				ex->ex_phy[i].phy_change_count =
1626 					phy_change_count;
1627 			*phy_id = i;
1628 			return 0;
1629 		}
1630 	}
1631 out:
1632 	return res;
1633 }
1634 
1635 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1636 {
1637 	int res;
1638 	u8  *rg_req;
1639 	struct smp_resp  *rg_resp;
1640 
1641 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1642 	if (!rg_req)
1643 		return -ENOMEM;
1644 
1645 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1646 	if (!rg_resp) {
1647 		kfree(rg_req);
1648 		return -ENOMEM;
1649 	}
1650 
1651 	rg_req[1] = SMP_REPORT_GENERAL;
1652 
1653 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1654 			       RG_RESP_SIZE);
1655 	if (res)
1656 		goto out;
1657 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1658 		res = rg_resp->result;
1659 		goto out;
1660 	}
1661 
1662 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1663 out:
1664 	kfree(rg_resp);
1665 	kfree(rg_req);
1666 	return res;
1667 }
1668 /**
1669  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1670  * @dev:domain device to be detect.
1671  * @src_dev: the device which originated BROADCAST(CHANGE).
1672  *
1673  * Add self-configuration expander suport. Suppose two expander cascading,
1674  * when the first level expander is self-configuring, hotplug the disks in
1675  * second level expander, BROADCAST(CHANGE) will not only be originated
1676  * in the second level expander, but also be originated in the first level
1677  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1678  * expander changed count in two level expanders will all increment at least
1679  * once, but the phy which chang count has changed is the source device which
1680  * we concerned.
1681  */
1682 
1683 static int sas_find_bcast_dev(struct domain_device *dev,
1684 			      struct domain_device **src_dev)
1685 {
1686 	struct expander_device *ex = &dev->ex_dev;
1687 	int ex_change_count = -1;
1688 	int phy_id = -1;
1689 	int res;
1690 	struct domain_device *ch;
1691 
1692 	res = sas_get_ex_change_count(dev, &ex_change_count);
1693 	if (res)
1694 		goto out;
1695 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1696 		/* Just detect if this expander phys phy change count changed,
1697 		* in order to determine if this expander originate BROADCAST,
1698 		* and do not update phy change count field in our structure.
1699 		*/
1700 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1701 		if (phy_id != -1) {
1702 			*src_dev = dev;
1703 			ex->ex_change_count = ex_change_count;
1704 			SAS_DPRINTK("Expander phy change count has changed\n");
1705 			return res;
1706 		} else
1707 			SAS_DPRINTK("Expander phys DID NOT change\n");
1708 	}
1709 	list_for_each_entry(ch, &ex->children, siblings) {
1710 		if (ch->dev_type == EDGE_DEV || ch->dev_type == FANOUT_DEV) {
1711 			res = sas_find_bcast_dev(ch, src_dev);
1712 			if (src_dev)
1713 				return res;
1714 		}
1715 	}
1716 out:
1717 	return res;
1718 }
1719 
1720 static void sas_unregister_ex_tree(struct domain_device *dev)
1721 {
1722 	struct expander_device *ex = &dev->ex_dev;
1723 	struct domain_device *child, *n;
1724 
1725 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1726 		if (child->dev_type == EDGE_DEV ||
1727 		    child->dev_type == FANOUT_DEV)
1728 			sas_unregister_ex_tree(child);
1729 		else
1730 			sas_unregister_dev(child);
1731 	}
1732 	sas_unregister_dev(dev);
1733 }
1734 
1735 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1736 					 int phy_id, bool last)
1737 {
1738 	struct expander_device *ex_dev = &parent->ex_dev;
1739 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1740 	struct domain_device *child, *n;
1741 	if (last) {
1742 		list_for_each_entry_safe(child, n,
1743 			&ex_dev->children, siblings) {
1744 			if (SAS_ADDR(child->sas_addr) ==
1745 			    SAS_ADDR(phy->attached_sas_addr)) {
1746 				if (child->dev_type == EDGE_DEV ||
1747 				    child->dev_type == FANOUT_DEV)
1748 					sas_unregister_ex_tree(child);
1749 				else
1750 					sas_unregister_dev(child);
1751 				break;
1752 			}
1753 		}
1754 		sas_disable_routing(parent, phy->attached_sas_addr);
1755 	}
1756 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1757 	sas_port_delete_phy(phy->port, phy->phy);
1758 	if (phy->port->num_phys == 0)
1759 		sas_port_delete(phy->port);
1760 	phy->port = NULL;
1761 }
1762 
1763 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1764 					  const int level)
1765 {
1766 	struct expander_device *ex_root = &root->ex_dev;
1767 	struct domain_device *child;
1768 	int res = 0;
1769 
1770 	list_for_each_entry(child, &ex_root->children, siblings) {
1771 		if (child->dev_type == EDGE_DEV ||
1772 		    child->dev_type == FANOUT_DEV) {
1773 			struct sas_expander_device *ex =
1774 				rphy_to_expander_device(child->rphy);
1775 
1776 			if (level > ex->level)
1777 				res = sas_discover_bfs_by_root_level(child,
1778 								     level);
1779 			else if (level == ex->level)
1780 				res = sas_ex_discover_devices(child, -1);
1781 		}
1782 	}
1783 	return res;
1784 }
1785 
1786 static int sas_discover_bfs_by_root(struct domain_device *dev)
1787 {
1788 	int res;
1789 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1790 	int level = ex->level+1;
1791 
1792 	res = sas_ex_discover_devices(dev, -1);
1793 	if (res)
1794 		goto out;
1795 	do {
1796 		res = sas_discover_bfs_by_root_level(dev, level);
1797 		mb();
1798 		level += 1;
1799 	} while (level <= dev->port->disc.max_level);
1800 out:
1801 	return res;
1802 }
1803 
1804 static int sas_discover_new(struct domain_device *dev, int phy_id)
1805 {
1806 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1807 	struct domain_device *child;
1808 	bool found = false;
1809 	int res, i;
1810 
1811 	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
1812 		    SAS_ADDR(dev->sas_addr), phy_id);
1813 	res = sas_ex_phy_discover(dev, phy_id);
1814 	if (res)
1815 		goto out;
1816 	/* to support the wide port inserted */
1817 	for (i = 0; i < dev->ex_dev.num_phys; i++) {
1818 		struct ex_phy *ex_phy_temp = &dev->ex_dev.ex_phy[i];
1819 		if (i == phy_id)
1820 			continue;
1821 		if (SAS_ADDR(ex_phy_temp->attached_sas_addr) ==
1822 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1823 			found = true;
1824 			break;
1825 		}
1826 	}
1827 	if (found) {
1828 		sas_ex_join_wide_port(dev, phy_id);
1829 		return 0;
1830 	}
1831 	res = sas_ex_discover_devices(dev, phy_id);
1832 	if (!res)
1833 		goto out;
1834 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1835 		if (SAS_ADDR(child->sas_addr) ==
1836 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1837 			if (child->dev_type == EDGE_DEV ||
1838 			    child->dev_type == FANOUT_DEV)
1839 				res = sas_discover_bfs_by_root(child);
1840 			break;
1841 		}
1842 	}
1843 out:
1844 	return res;
1845 }
1846 
1847 static int sas_rediscover_dev(struct domain_device *dev, int phy_id, bool last)
1848 {
1849 	struct expander_device *ex = &dev->ex_dev;
1850 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1851 	u8 attached_sas_addr[8];
1852 	int res;
1853 
1854 	res = sas_get_phy_attached_sas_addr(dev, phy_id, attached_sas_addr);
1855 	switch (res) {
1856 	case SMP_RESP_NO_PHY:
1857 		phy->phy_state = PHY_NOT_PRESENT;
1858 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1859 		goto out; break;
1860 	case SMP_RESP_PHY_VACANT:
1861 		phy->phy_state = PHY_VACANT;
1862 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1863 		goto out; break;
1864 	case SMP_RESP_FUNC_ACC:
1865 		break;
1866 	}
1867 
1868 	if (SAS_ADDR(attached_sas_addr) == 0) {
1869 		phy->phy_state = PHY_EMPTY;
1870 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1871 	} else if (SAS_ADDR(attached_sas_addr) ==
1872 		   SAS_ADDR(phy->attached_sas_addr)) {
1873 		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter\n",
1874 			    SAS_ADDR(dev->sas_addr), phy_id);
1875 		sas_ex_phy_discover(dev, phy_id);
1876 	} else
1877 		res = sas_discover_new(dev, phy_id);
1878 out:
1879 	return res;
1880 }
1881 
1882 /**
1883  * sas_rediscover - revalidate the domain.
1884  * @dev:domain device to be detect.
1885  * @phy_id: the phy id will be detected.
1886  *
1887  * NOTE: this process _must_ quit (return) as soon as any connection
1888  * errors are encountered.  Connection recovery is done elsewhere.
1889  * Discover process only interrogates devices in order to discover the
1890  * domain.For plugging out, we un-register the device only when it is
1891  * the last phy in the port, for other phys in this port, we just delete it
1892  * from the port.For inserting, we do discovery when it is the
1893  * first phy,for other phys in this port, we add it to the port to
1894  * forming the wide-port.
1895  */
1896 static int sas_rediscover(struct domain_device *dev, const int phy_id)
1897 {
1898 	struct expander_device *ex = &dev->ex_dev;
1899 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
1900 	int res = 0;
1901 	int i;
1902 	bool last = true;	/* is this the last phy of the port */
1903 
1904 	SAS_DPRINTK("ex %016llx phy%d originated BROADCAST(CHANGE)\n",
1905 		    SAS_ADDR(dev->sas_addr), phy_id);
1906 
1907 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
1908 		for (i = 0; i < ex->num_phys; i++) {
1909 			struct ex_phy *phy = &ex->ex_phy[i];
1910 
1911 			if (i == phy_id)
1912 				continue;
1913 			if (SAS_ADDR(phy->attached_sas_addr) ==
1914 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
1915 				SAS_DPRINTK("phy%d part of wide port with "
1916 					    "phy%d\n", phy_id, i);
1917 				last = false;
1918 				break;
1919 			}
1920 		}
1921 		res = sas_rediscover_dev(dev, phy_id, last);
1922 	} else
1923 		res = sas_discover_new(dev, phy_id);
1924 	return res;
1925 }
1926 
1927 /**
1928  * sas_revalidate_domain -- revalidate the domain
1929  * @port: port to the domain of interest
1930  *
1931  * NOTE: this process _must_ quit (return) as soon as any connection
1932  * errors are encountered.  Connection recovery is done elsewhere.
1933  * Discover process only interrogates devices in order to discover the
1934  * domain.
1935  */
1936 int sas_ex_revalidate_domain(struct domain_device *port_dev)
1937 {
1938 	int res;
1939 	struct domain_device *dev = NULL;
1940 
1941 	res = sas_find_bcast_dev(port_dev, &dev);
1942 	if (res)
1943 		goto out;
1944 	if (dev) {
1945 		struct expander_device *ex = &dev->ex_dev;
1946 		int i = 0, phy_id;
1947 
1948 		do {
1949 			phy_id = -1;
1950 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
1951 			if (phy_id == -1)
1952 				break;
1953 			res = sas_rediscover(dev, phy_id);
1954 			i = phy_id + 1;
1955 		} while (i < ex->num_phys);
1956 	}
1957 out:
1958 	return res;
1959 }
1960 
1961 int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
1962 		    struct request *req)
1963 {
1964 	struct domain_device *dev;
1965 	int ret, type;
1966 	struct request *rsp = req->next_rq;
1967 
1968 	if (!rsp) {
1969 		printk("%s: space for a smp response is missing\n",
1970 		       __func__);
1971 		return -EINVAL;
1972 	}
1973 
1974 	/* no rphy means no smp target support (ie aic94xx host) */
1975 	if (!rphy)
1976 		return sas_smp_host_handler(shost, req, rsp);
1977 
1978 	type = rphy->identify.device_type;
1979 
1980 	if (type != SAS_EDGE_EXPANDER_DEVICE &&
1981 	    type != SAS_FANOUT_EXPANDER_DEVICE) {
1982 		printk("%s: can we send a smp request to a device?\n",
1983 		       __func__);
1984 		return -EINVAL;
1985 	}
1986 
1987 	dev = sas_find_dev_by_rphy(rphy);
1988 	if (!dev) {
1989 		printk("%s: fail to find a domain_device?\n", __func__);
1990 		return -EINVAL;
1991 	}
1992 
1993 	/* do we need to support multiple segments? */
1994 	if (req->bio->bi_vcnt > 1 || rsp->bio->bi_vcnt > 1) {
1995 		printk("%s: multiple segments req %u %u, rsp %u %u\n",
1996 		       __func__, req->bio->bi_vcnt, blk_rq_bytes(req),
1997 		       rsp->bio->bi_vcnt, blk_rq_bytes(rsp));
1998 		return -EINVAL;
1999 	}
2000 
2001 	ret = smp_execute_task(dev, bio_data(req->bio), blk_rq_bytes(req),
2002 			       bio_data(rsp->bio), blk_rq_bytes(rsp));
2003 	if (ret > 0) {
2004 		/* positive number is the untransferred residual */
2005 		rsp->resid_len = ret;
2006 		req->resid_len = 0;
2007 		ret = 0;
2008 	} else if (ret == 0) {
2009 		rsp->resid_len = 0;
2010 		req->resid_len = 0;
2011 	}
2012 
2013 	return ret;
2014 }
2015