xref: /linux/drivers/scsi/libsas/sas_expander.c (revision d593b5413d13be31782385bf5b27af3b3bad59eb)
1 /*
2  * Serial Attached SCSI (SAS) Expander discovery and configuration
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
22  *
23  */
24 
25 #include <linux/scatterlist.h>
26 #include <linux/blkdev.h>
27 #include <linux/slab.h>
28 
29 #include "sas_internal.h"
30 
31 #include <scsi/scsi_transport.h>
32 #include <scsi/scsi_transport_sas.h>
33 #include "../scsi_sas_internal.h"
34 
35 static int sas_discover_expander(struct domain_device *dev);
36 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
37 static int sas_configure_phy(struct domain_device *dev, int phy_id,
38 			     u8 *sas_addr, int include);
39 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
40 
41 /* ---------- SMP task management ---------- */
42 
43 static void smp_task_timedout(unsigned long _task)
44 {
45 	struct sas_task *task = (void *) _task;
46 	unsigned long flags;
47 
48 	spin_lock_irqsave(&task->task_state_lock, flags);
49 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
50 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
51 	spin_unlock_irqrestore(&task->task_state_lock, flags);
52 
53 	complete(&task->completion);
54 }
55 
56 static void smp_task_done(struct sas_task *task)
57 {
58 	if (!del_timer(&task->timer))
59 		return;
60 	complete(&task->completion);
61 }
62 
63 /* Give it some long enough timeout. In seconds. */
64 #define SMP_TIMEOUT 10
65 
66 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
67 			    void *resp, int resp_size)
68 {
69 	int res, retry;
70 	struct sas_task *task = NULL;
71 	struct sas_internal *i =
72 		to_sas_internal(dev->port->ha->core.shost->transportt);
73 
74 	for (retry = 0; retry < 3; retry++) {
75 		task = sas_alloc_task(GFP_KERNEL);
76 		if (!task)
77 			return -ENOMEM;
78 
79 		task->dev = dev;
80 		task->task_proto = dev->tproto;
81 		sg_init_one(&task->smp_task.smp_req, req, req_size);
82 		sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
83 
84 		task->task_done = smp_task_done;
85 
86 		task->timer.data = (unsigned long) task;
87 		task->timer.function = smp_task_timedout;
88 		task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
89 		add_timer(&task->timer);
90 
91 		res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
92 
93 		if (res) {
94 			del_timer(&task->timer);
95 			SAS_DPRINTK("executing SMP task failed:%d\n", res);
96 			goto ex_err;
97 		}
98 
99 		wait_for_completion(&task->completion);
100 		res = -ECOMM;
101 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
102 			SAS_DPRINTK("smp task timed out or aborted\n");
103 			i->dft->lldd_abort_task(task);
104 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
105 				SAS_DPRINTK("SMP task aborted and not done\n");
106 				goto ex_err;
107 			}
108 		}
109 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
110 		    task->task_status.stat == SAM_STAT_GOOD) {
111 			res = 0;
112 			break;
113 		} if (task->task_status.resp == SAS_TASK_COMPLETE &&
114 		      task->task_status.stat == SAS_DATA_UNDERRUN) {
115 			/* no error, but return the number of bytes of
116 			 * underrun */
117 			res = task->task_status.residual;
118 			break;
119 		} if (task->task_status.resp == SAS_TASK_COMPLETE &&
120 		      task->task_status.stat == SAS_DATA_OVERRUN) {
121 			res = -EMSGSIZE;
122 			break;
123 		} else {
124 			SAS_DPRINTK("%s: task to dev %016llx response: 0x%x "
125 				    "status 0x%x\n", __func__,
126 				    SAS_ADDR(dev->sas_addr),
127 				    task->task_status.resp,
128 				    task->task_status.stat);
129 			sas_free_task(task);
130 			task = NULL;
131 		}
132 	}
133 ex_err:
134 	BUG_ON(retry == 3 && task != NULL);
135 	if (task != NULL) {
136 		sas_free_task(task);
137 	}
138 	return res;
139 }
140 
141 /* ---------- Allocations ---------- */
142 
143 static inline void *alloc_smp_req(int size)
144 {
145 	u8 *p = kzalloc(size, GFP_KERNEL);
146 	if (p)
147 		p[0] = SMP_REQUEST;
148 	return p;
149 }
150 
151 static inline void *alloc_smp_resp(int size)
152 {
153 	return kzalloc(size, GFP_KERNEL);
154 }
155 
156 /* ---------- Expander configuration ---------- */
157 
158 static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
159 			   void *disc_resp)
160 {
161 	struct expander_device *ex = &dev->ex_dev;
162 	struct ex_phy *phy = &ex->ex_phy[phy_id];
163 	struct smp_resp *resp = disc_resp;
164 	struct discover_resp *dr = &resp->disc;
165 	struct sas_rphy *rphy = dev->rphy;
166 	int rediscover = (phy->phy != NULL);
167 
168 	if (!rediscover) {
169 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
170 
171 		/* FIXME: error_handling */
172 		BUG_ON(!phy->phy);
173 	}
174 
175 	switch (resp->result) {
176 	case SMP_RESP_PHY_VACANT:
177 		phy->phy_state = PHY_VACANT;
178 		break;
179 	default:
180 		phy->phy_state = PHY_NOT_PRESENT;
181 		break;
182 	case SMP_RESP_FUNC_ACC:
183 		phy->phy_state = PHY_EMPTY; /* do not know yet */
184 		break;
185 	}
186 
187 	phy->phy_id = phy_id;
188 	phy->attached_dev_type = dr->attached_dev_type;
189 	phy->linkrate = dr->linkrate;
190 	phy->attached_sata_host = dr->attached_sata_host;
191 	phy->attached_sata_dev  = dr->attached_sata_dev;
192 	phy->attached_sata_ps   = dr->attached_sata_ps;
193 	phy->attached_iproto = dr->iproto << 1;
194 	phy->attached_tproto = dr->tproto << 1;
195 	memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
196 	phy->attached_phy_id = dr->attached_phy_id;
197 	phy->phy_change_count = dr->change_count;
198 	phy->routing_attr = dr->routing_attr;
199 	phy->virtual = dr->virtual;
200 	phy->last_da_index = -1;
201 
202 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
203 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
204 	phy->phy->identify.phy_identifier = phy_id;
205 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
206 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
207 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
208 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
209 	phy->phy->negotiated_linkrate = phy->linkrate;
210 
211 	if (!rediscover)
212 		if (sas_phy_add(phy->phy)) {
213 			sas_phy_free(phy->phy);
214 			return;
215 		}
216 
217 	SAS_DPRINTK("ex %016llx phy%02d:%c attached: %016llx\n",
218 		    SAS_ADDR(dev->sas_addr), phy->phy_id,
219 		    phy->routing_attr == TABLE_ROUTING ? 'T' :
220 		    phy->routing_attr == DIRECT_ROUTING ? 'D' :
221 		    phy->routing_attr == SUBTRACTIVE_ROUTING ? 'S' : '?',
222 		    SAS_ADDR(phy->attached_sas_addr));
223 
224 	return;
225 }
226 
227 #define DISCOVER_REQ_SIZE  16
228 #define DISCOVER_RESP_SIZE 56
229 
230 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
231 				      u8 *disc_resp, int single)
232 {
233 	int i, res;
234 
235 	disc_req[9] = single;
236 	for (i = 1 ; i < 3; i++) {
237 		struct discover_resp *dr;
238 
239 		res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
240 				       disc_resp, DISCOVER_RESP_SIZE);
241 		if (res)
242 			return res;
243 		/* This is detecting a failure to transmit initial
244 		 * dev to host FIS as described in section G.5 of
245 		 * sas-2 r 04b */
246 		dr = &((struct smp_resp *)disc_resp)->disc;
247 		if (memcmp(dev->sas_addr, dr->attached_sas_addr,
248 			  SAS_ADDR_SIZE) == 0) {
249 			sas_printk("Found loopback topology, just ignore it!\n");
250 			return 0;
251 		}
252 		if (!(dr->attached_dev_type == 0 &&
253 		      dr->attached_sata_dev))
254 			break;
255 		/* In order to generate the dev to host FIS, we
256 		 * send a link reset to the expander port */
257 		sas_smp_phy_control(dev, single, PHY_FUNC_LINK_RESET, NULL);
258 		/* Wait for the reset to trigger the negotiation */
259 		msleep(500);
260 	}
261 	sas_set_ex_phy(dev, single, disc_resp);
262 	return 0;
263 }
264 
265 static int sas_ex_phy_discover(struct domain_device *dev, int single)
266 {
267 	struct expander_device *ex = &dev->ex_dev;
268 	int  res = 0;
269 	u8   *disc_req;
270 	u8   *disc_resp;
271 
272 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
273 	if (!disc_req)
274 		return -ENOMEM;
275 
276 	disc_resp = alloc_smp_req(DISCOVER_RESP_SIZE);
277 	if (!disc_resp) {
278 		kfree(disc_req);
279 		return -ENOMEM;
280 	}
281 
282 	disc_req[1] = SMP_DISCOVER;
283 
284 	if (0 <= single && single < ex->num_phys) {
285 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
286 	} else {
287 		int i;
288 
289 		for (i = 0; i < ex->num_phys; i++) {
290 			res = sas_ex_phy_discover_helper(dev, disc_req,
291 							 disc_resp, i);
292 			if (res)
293 				goto out_err;
294 		}
295 	}
296 out_err:
297 	kfree(disc_resp);
298 	kfree(disc_req);
299 	return res;
300 }
301 
302 static int sas_expander_discover(struct domain_device *dev)
303 {
304 	struct expander_device *ex = &dev->ex_dev;
305 	int res = -ENOMEM;
306 
307 	ex->ex_phy = kzalloc(sizeof(*ex->ex_phy)*ex->num_phys, GFP_KERNEL);
308 	if (!ex->ex_phy)
309 		return -ENOMEM;
310 
311 	res = sas_ex_phy_discover(dev, -1);
312 	if (res)
313 		goto out_err;
314 
315 	return 0;
316  out_err:
317 	kfree(ex->ex_phy);
318 	ex->ex_phy = NULL;
319 	return res;
320 }
321 
322 #define MAX_EXPANDER_PHYS 128
323 
324 static void ex_assign_report_general(struct domain_device *dev,
325 					    struct smp_resp *resp)
326 {
327 	struct report_general_resp *rg = &resp->rg;
328 
329 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
330 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
331 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
332 	dev->ex_dev.conf_route_table = rg->conf_route_table;
333 	dev->ex_dev.configuring = rg->configuring;
334 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
335 }
336 
337 #define RG_REQ_SIZE   8
338 #define RG_RESP_SIZE 32
339 
340 static int sas_ex_general(struct domain_device *dev)
341 {
342 	u8 *rg_req;
343 	struct smp_resp *rg_resp;
344 	int res;
345 	int i;
346 
347 	rg_req = alloc_smp_req(RG_REQ_SIZE);
348 	if (!rg_req)
349 		return -ENOMEM;
350 
351 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
352 	if (!rg_resp) {
353 		kfree(rg_req);
354 		return -ENOMEM;
355 	}
356 
357 	rg_req[1] = SMP_REPORT_GENERAL;
358 
359 	for (i = 0; i < 5; i++) {
360 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
361 				       RG_RESP_SIZE);
362 
363 		if (res) {
364 			SAS_DPRINTK("RG to ex %016llx failed:0x%x\n",
365 				    SAS_ADDR(dev->sas_addr), res);
366 			goto out;
367 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
368 			SAS_DPRINTK("RG:ex %016llx returned SMP result:0x%x\n",
369 				    SAS_ADDR(dev->sas_addr), rg_resp->result);
370 			res = rg_resp->result;
371 			goto out;
372 		}
373 
374 		ex_assign_report_general(dev, rg_resp);
375 
376 		if (dev->ex_dev.configuring) {
377 			SAS_DPRINTK("RG: ex %llx self-configuring...\n",
378 				    SAS_ADDR(dev->sas_addr));
379 			schedule_timeout_interruptible(5*HZ);
380 		} else
381 			break;
382 	}
383 out:
384 	kfree(rg_req);
385 	kfree(rg_resp);
386 	return res;
387 }
388 
389 static void ex_assign_manuf_info(struct domain_device *dev, void
390 					*_mi_resp)
391 {
392 	u8 *mi_resp = _mi_resp;
393 	struct sas_rphy *rphy = dev->rphy;
394 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
395 
396 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
397 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
398 	memcpy(edev->product_rev, mi_resp + 36,
399 	       SAS_EXPANDER_PRODUCT_REV_LEN);
400 
401 	if (mi_resp[8] & 1) {
402 		memcpy(edev->component_vendor_id, mi_resp + 40,
403 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
404 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
405 		edev->component_revision_id = mi_resp[50];
406 	}
407 }
408 
409 #define MI_REQ_SIZE   8
410 #define MI_RESP_SIZE 64
411 
412 static int sas_ex_manuf_info(struct domain_device *dev)
413 {
414 	u8 *mi_req;
415 	u8 *mi_resp;
416 	int res;
417 
418 	mi_req = alloc_smp_req(MI_REQ_SIZE);
419 	if (!mi_req)
420 		return -ENOMEM;
421 
422 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
423 	if (!mi_resp) {
424 		kfree(mi_req);
425 		return -ENOMEM;
426 	}
427 
428 	mi_req[1] = SMP_REPORT_MANUF_INFO;
429 
430 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
431 	if (res) {
432 		SAS_DPRINTK("MI: ex %016llx failed:0x%x\n",
433 			    SAS_ADDR(dev->sas_addr), res);
434 		goto out;
435 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
436 		SAS_DPRINTK("MI ex %016llx returned SMP result:0x%x\n",
437 			    SAS_ADDR(dev->sas_addr), mi_resp[2]);
438 		goto out;
439 	}
440 
441 	ex_assign_manuf_info(dev, mi_resp);
442 out:
443 	kfree(mi_req);
444 	kfree(mi_resp);
445 	return res;
446 }
447 
448 #define PC_REQ_SIZE  44
449 #define PC_RESP_SIZE 8
450 
451 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
452 			enum phy_func phy_func,
453 			struct sas_phy_linkrates *rates)
454 {
455 	u8 *pc_req;
456 	u8 *pc_resp;
457 	int res;
458 
459 	pc_req = alloc_smp_req(PC_REQ_SIZE);
460 	if (!pc_req)
461 		return -ENOMEM;
462 
463 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
464 	if (!pc_resp) {
465 		kfree(pc_req);
466 		return -ENOMEM;
467 	}
468 
469 	pc_req[1] = SMP_PHY_CONTROL;
470 	pc_req[9] = phy_id;
471 	pc_req[10]= phy_func;
472 	if (rates) {
473 		pc_req[32] = rates->minimum_linkrate << 4;
474 		pc_req[33] = rates->maximum_linkrate << 4;
475 	}
476 
477 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
478 
479 	kfree(pc_resp);
480 	kfree(pc_req);
481 	return res;
482 }
483 
484 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
485 {
486 	struct expander_device *ex = &dev->ex_dev;
487 	struct ex_phy *phy = &ex->ex_phy[phy_id];
488 
489 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
490 	phy->linkrate = SAS_PHY_DISABLED;
491 }
492 
493 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
494 {
495 	struct expander_device *ex = &dev->ex_dev;
496 	int i;
497 
498 	for (i = 0; i < ex->num_phys; i++) {
499 		struct ex_phy *phy = &ex->ex_phy[i];
500 
501 		if (phy->phy_state == PHY_VACANT ||
502 		    phy->phy_state == PHY_NOT_PRESENT)
503 			continue;
504 
505 		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
506 			sas_ex_disable_phy(dev, i);
507 	}
508 }
509 
510 static int sas_dev_present_in_domain(struct asd_sas_port *port,
511 					    u8 *sas_addr)
512 {
513 	struct domain_device *dev;
514 
515 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
516 		return 1;
517 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
518 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
519 			return 1;
520 	}
521 	return 0;
522 }
523 
524 #define RPEL_REQ_SIZE	16
525 #define RPEL_RESP_SIZE	32
526 int sas_smp_get_phy_events(struct sas_phy *phy)
527 {
528 	int res;
529 	u8 *req;
530 	u8 *resp;
531 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
532 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
533 
534 	req = alloc_smp_req(RPEL_REQ_SIZE);
535 	if (!req)
536 		return -ENOMEM;
537 
538 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
539 	if (!resp) {
540 		kfree(req);
541 		return -ENOMEM;
542 	}
543 
544 	req[1] = SMP_REPORT_PHY_ERR_LOG;
545 	req[9] = phy->number;
546 
547 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
548 			            resp, RPEL_RESP_SIZE);
549 
550 	if (!res)
551 		goto out;
552 
553 	phy->invalid_dword_count = scsi_to_u32(&resp[12]);
554 	phy->running_disparity_error_count = scsi_to_u32(&resp[16]);
555 	phy->loss_of_dword_sync_count = scsi_to_u32(&resp[20]);
556 	phy->phy_reset_problem_count = scsi_to_u32(&resp[24]);
557 
558  out:
559 	kfree(resp);
560 	return res;
561 
562 }
563 
564 #ifdef CONFIG_SCSI_SAS_ATA
565 
566 #define RPS_REQ_SIZE  16
567 #define RPS_RESP_SIZE 60
568 
569 static int sas_get_report_phy_sata(struct domain_device *dev,
570 					  int phy_id,
571 					  struct smp_resp *rps_resp)
572 {
573 	int res;
574 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
575 	u8 *resp = (u8 *)rps_resp;
576 
577 	if (!rps_req)
578 		return -ENOMEM;
579 
580 	rps_req[1] = SMP_REPORT_PHY_SATA;
581 	rps_req[9] = phy_id;
582 
583 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
584 			            rps_resp, RPS_RESP_SIZE);
585 
586 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
587 	 * standards cockup here.  sas-2 explicitly specifies the FIS
588 	 * should be encoded so that FIS type is in resp[24].
589 	 * However, some expanders endian reverse this.  Undo the
590 	 * reversal here */
591 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
592 		int i;
593 
594 		for (i = 0; i < 5; i++) {
595 			int j = 24 + (i*4);
596 			u8 a, b;
597 			a = resp[j + 0];
598 			b = resp[j + 1];
599 			resp[j + 0] = resp[j + 3];
600 			resp[j + 1] = resp[j + 2];
601 			resp[j + 2] = b;
602 			resp[j + 3] = a;
603 		}
604 	}
605 
606 	kfree(rps_req);
607 	return res;
608 }
609 #endif
610 
611 static void sas_ex_get_linkrate(struct domain_device *parent,
612 				       struct domain_device *child,
613 				       struct ex_phy *parent_phy)
614 {
615 	struct expander_device *parent_ex = &parent->ex_dev;
616 	struct sas_port *port;
617 	int i;
618 
619 	child->pathways = 0;
620 
621 	port = parent_phy->port;
622 
623 	for (i = 0; i < parent_ex->num_phys; i++) {
624 		struct ex_phy *phy = &parent_ex->ex_phy[i];
625 
626 		if (phy->phy_state == PHY_VACANT ||
627 		    phy->phy_state == PHY_NOT_PRESENT)
628 			continue;
629 
630 		if (SAS_ADDR(phy->attached_sas_addr) ==
631 		    SAS_ADDR(child->sas_addr)) {
632 
633 			child->min_linkrate = min(parent->min_linkrate,
634 						  phy->linkrate);
635 			child->max_linkrate = max(parent->max_linkrate,
636 						  phy->linkrate);
637 			child->pathways++;
638 			sas_port_add_phy(port, phy->phy);
639 		}
640 	}
641 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
642 	child->pathways = min(child->pathways, parent->pathways);
643 }
644 
645 static struct domain_device *sas_ex_discover_end_dev(
646 	struct domain_device *parent, int phy_id)
647 {
648 	struct expander_device *parent_ex = &parent->ex_dev;
649 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
650 	struct domain_device *child = NULL;
651 	struct sas_rphy *rphy;
652 	int res;
653 
654 	if (phy->attached_sata_host || phy->attached_sata_ps)
655 		return NULL;
656 
657 	child = kzalloc(sizeof(*child), GFP_KERNEL);
658 	if (!child)
659 		return NULL;
660 
661 	child->parent = parent;
662 	child->port   = parent->port;
663 	child->iproto = phy->attached_iproto;
664 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
665 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
666 	if (!phy->port) {
667 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
668 		if (unlikely(!phy->port))
669 			goto out_err;
670 		if (unlikely(sas_port_add(phy->port) != 0)) {
671 			sas_port_free(phy->port);
672 			goto out_err;
673 		}
674 	}
675 	sas_ex_get_linkrate(parent, child, phy);
676 
677 #ifdef CONFIG_SCSI_SAS_ATA
678 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
679 		child->dev_type = SATA_DEV;
680 		if (phy->attached_tproto & SAS_PROTOCOL_STP)
681 			child->tproto = phy->attached_tproto;
682 		if (phy->attached_sata_dev)
683 			child->tproto |= SATA_DEV;
684 		res = sas_get_report_phy_sata(parent, phy_id,
685 					      &child->sata_dev.rps_resp);
686 		if (res) {
687 			SAS_DPRINTK("report phy sata to %016llx:0x%x returned "
688 				    "0x%x\n", SAS_ADDR(parent->sas_addr),
689 				    phy_id, res);
690 			goto out_free;
691 		}
692 		memcpy(child->frame_rcvd, &child->sata_dev.rps_resp.rps.fis,
693 		       sizeof(struct dev_to_host_fis));
694 
695 		rphy = sas_end_device_alloc(phy->port);
696 		if (unlikely(!rphy))
697 			goto out_free;
698 
699 		sas_init_dev(child);
700 
701 		child->rphy = rphy;
702 
703 		spin_lock_irq(&parent->port->dev_list_lock);
704 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
705 		spin_unlock_irq(&parent->port->dev_list_lock);
706 
707 		res = sas_discover_sata(child);
708 		if (res) {
709 			SAS_DPRINTK("sas_discover_sata() for device %16llx at "
710 				    "%016llx:0x%x returned 0x%x\n",
711 				    SAS_ADDR(child->sas_addr),
712 				    SAS_ADDR(parent->sas_addr), phy_id, res);
713 			goto out_list_del;
714 		}
715 	} else
716 #endif
717 	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
718 		child->dev_type = SAS_END_DEV;
719 		rphy = sas_end_device_alloc(phy->port);
720 		/* FIXME: error handling */
721 		if (unlikely(!rphy))
722 			goto out_free;
723 		child->tproto = phy->attached_tproto;
724 		sas_init_dev(child);
725 
726 		child->rphy = rphy;
727 		sas_fill_in_rphy(child, rphy);
728 
729 		spin_lock_irq(&parent->port->dev_list_lock);
730 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
731 		spin_unlock_irq(&parent->port->dev_list_lock);
732 
733 		res = sas_discover_end_dev(child);
734 		if (res) {
735 			SAS_DPRINTK("sas_discover_end_dev() for device %16llx "
736 				    "at %016llx:0x%x returned 0x%x\n",
737 				    SAS_ADDR(child->sas_addr),
738 				    SAS_ADDR(parent->sas_addr), phy_id, res);
739 			goto out_list_del;
740 		}
741 	} else {
742 		SAS_DPRINTK("target proto 0x%x at %016llx:0x%x not handled\n",
743 			    phy->attached_tproto, SAS_ADDR(parent->sas_addr),
744 			    phy_id);
745 		goto out_free;
746 	}
747 
748 	list_add_tail(&child->siblings, &parent_ex->children);
749 	return child;
750 
751  out_list_del:
752 	sas_rphy_free(child->rphy);
753 	child->rphy = NULL;
754 	list_del(&child->dev_list_node);
755  out_free:
756 	sas_port_delete(phy->port);
757  out_err:
758 	phy->port = NULL;
759 	kfree(child);
760 	return NULL;
761 }
762 
763 /* See if this phy is part of a wide port */
764 static int sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
765 {
766 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
767 	int i;
768 
769 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
770 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
771 
772 		if (ephy == phy)
773 			continue;
774 
775 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
776 			    SAS_ADDR_SIZE) && ephy->port) {
777 			sas_port_add_phy(ephy->port, phy->phy);
778 			phy->port = ephy->port;
779 			phy->phy_state = PHY_DEVICE_DISCOVERED;
780 			return 0;
781 		}
782 	}
783 
784 	return -ENODEV;
785 }
786 
787 static struct domain_device *sas_ex_discover_expander(
788 	struct domain_device *parent, int phy_id)
789 {
790 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
791 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
792 	struct domain_device *child = NULL;
793 	struct sas_rphy *rphy;
794 	struct sas_expander_device *edev;
795 	struct asd_sas_port *port;
796 	int res;
797 
798 	if (phy->routing_attr == DIRECT_ROUTING) {
799 		SAS_DPRINTK("ex %016llx:0x%x:D <--> ex %016llx:0x%x is not "
800 			    "allowed\n",
801 			    SAS_ADDR(parent->sas_addr), phy_id,
802 			    SAS_ADDR(phy->attached_sas_addr),
803 			    phy->attached_phy_id);
804 		return NULL;
805 	}
806 	child = kzalloc(sizeof(*child), GFP_KERNEL);
807 	if (!child)
808 		return NULL;
809 
810 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
811 	/* FIXME: better error handling */
812 	BUG_ON(sas_port_add(phy->port) != 0);
813 
814 
815 	switch (phy->attached_dev_type) {
816 	case EDGE_DEV:
817 		rphy = sas_expander_alloc(phy->port,
818 					  SAS_EDGE_EXPANDER_DEVICE);
819 		break;
820 	case FANOUT_DEV:
821 		rphy = sas_expander_alloc(phy->port,
822 					  SAS_FANOUT_EXPANDER_DEVICE);
823 		break;
824 	default:
825 		rphy = NULL;	/* shut gcc up */
826 		BUG();
827 	}
828 	port = parent->port;
829 	child->rphy = rphy;
830 	edev = rphy_to_expander_device(rphy);
831 	child->dev_type = phy->attached_dev_type;
832 	child->parent = parent;
833 	child->port = port;
834 	child->iproto = phy->attached_iproto;
835 	child->tproto = phy->attached_tproto;
836 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
837 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
838 	sas_ex_get_linkrate(parent, child, phy);
839 	edev->level = parent_ex->level + 1;
840 	parent->port->disc.max_level = max(parent->port->disc.max_level,
841 					   edev->level);
842 	sas_init_dev(child);
843 	sas_fill_in_rphy(child, rphy);
844 	sas_rphy_add(rphy);
845 
846 	spin_lock_irq(&parent->port->dev_list_lock);
847 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
848 	spin_unlock_irq(&parent->port->dev_list_lock);
849 
850 	res = sas_discover_expander(child);
851 	if (res) {
852 		spin_lock_irq(&parent->port->dev_list_lock);
853 		list_del(&child->dev_list_node);
854 		spin_unlock_irq(&parent->port->dev_list_lock);
855 		kfree(child);
856 		return NULL;
857 	}
858 	list_add_tail(&child->siblings, &parent->ex_dev.children);
859 	return child;
860 }
861 
862 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
863 {
864 	struct expander_device *ex = &dev->ex_dev;
865 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
866 	struct domain_device *child = NULL;
867 	int res = 0;
868 
869 	/* Phy state */
870 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
871 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
872 			res = sas_ex_phy_discover(dev, phy_id);
873 		if (res)
874 			return res;
875 	}
876 
877 	/* Parent and domain coherency */
878 	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
879 			     SAS_ADDR(dev->port->sas_addr))) {
880 		sas_add_parent_port(dev, phy_id);
881 		return 0;
882 	}
883 	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
884 			    SAS_ADDR(dev->parent->sas_addr))) {
885 		sas_add_parent_port(dev, phy_id);
886 		if (ex_phy->routing_attr == TABLE_ROUTING)
887 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
888 		return 0;
889 	}
890 
891 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
892 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
893 
894 	if (ex_phy->attached_dev_type == NO_DEVICE) {
895 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
896 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
897 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
898 		}
899 		return 0;
900 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
901 		return 0;
902 
903 	if (ex_phy->attached_dev_type != SAS_END_DEV &&
904 	    ex_phy->attached_dev_type != FANOUT_DEV &&
905 	    ex_phy->attached_dev_type != EDGE_DEV) {
906 		SAS_DPRINTK("unknown device type(0x%x) attached to ex %016llx "
907 			    "phy 0x%x\n", ex_phy->attached_dev_type,
908 			    SAS_ADDR(dev->sas_addr),
909 			    phy_id);
910 		return 0;
911 	}
912 
913 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
914 	if (res) {
915 		SAS_DPRINTK("configure routing for dev %016llx "
916 			    "reported 0x%x. Forgotten\n",
917 			    SAS_ADDR(ex_phy->attached_sas_addr), res);
918 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
919 		return res;
920 	}
921 
922 	res = sas_ex_join_wide_port(dev, phy_id);
923 	if (!res) {
924 		SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
925 			    phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
926 		return res;
927 	}
928 
929 	switch (ex_phy->attached_dev_type) {
930 	case SAS_END_DEV:
931 		child = sas_ex_discover_end_dev(dev, phy_id);
932 		break;
933 	case FANOUT_DEV:
934 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
935 			SAS_DPRINTK("second fanout expander %016llx phy 0x%x "
936 				    "attached to ex %016llx phy 0x%x\n",
937 				    SAS_ADDR(ex_phy->attached_sas_addr),
938 				    ex_phy->attached_phy_id,
939 				    SAS_ADDR(dev->sas_addr),
940 				    phy_id);
941 			sas_ex_disable_phy(dev, phy_id);
942 			break;
943 		} else
944 			memcpy(dev->port->disc.fanout_sas_addr,
945 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
946 		/* fallthrough */
947 	case EDGE_DEV:
948 		child = sas_ex_discover_expander(dev, phy_id);
949 		break;
950 	default:
951 		break;
952 	}
953 
954 	if (child) {
955 		int i;
956 
957 		for (i = 0; i < ex->num_phys; i++) {
958 			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
959 			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
960 				continue;
961 			/*
962 			 * Due to races, the phy might not get added to the
963 			 * wide port, so we add the phy to the wide port here.
964 			 */
965 			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
966 			    SAS_ADDR(child->sas_addr)) {
967 				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
968 				res = sas_ex_join_wide_port(dev, i);
969 				if (!res)
970 					SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
971 						    i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
972 
973 			}
974 		}
975 	}
976 
977 	return res;
978 }
979 
980 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
981 {
982 	struct expander_device *ex = &dev->ex_dev;
983 	int i;
984 
985 	for (i = 0; i < ex->num_phys; i++) {
986 		struct ex_phy *phy = &ex->ex_phy[i];
987 
988 		if (phy->phy_state == PHY_VACANT ||
989 		    phy->phy_state == PHY_NOT_PRESENT)
990 			continue;
991 
992 		if ((phy->attached_dev_type == EDGE_DEV ||
993 		     phy->attached_dev_type == FANOUT_DEV) &&
994 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
995 
996 			memcpy(sub_addr, phy->attached_sas_addr,SAS_ADDR_SIZE);
997 
998 			return 1;
999 		}
1000 	}
1001 	return 0;
1002 }
1003 
1004 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1005 {
1006 	struct expander_device *ex = &dev->ex_dev;
1007 	struct domain_device *child;
1008 	u8 sub_addr[8] = {0, };
1009 
1010 	list_for_each_entry(child, &ex->children, siblings) {
1011 		if (child->dev_type != EDGE_DEV &&
1012 		    child->dev_type != FANOUT_DEV)
1013 			continue;
1014 		if (sub_addr[0] == 0) {
1015 			sas_find_sub_addr(child, sub_addr);
1016 			continue;
1017 		} else {
1018 			u8 s2[8];
1019 
1020 			if (sas_find_sub_addr(child, s2) &&
1021 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1022 
1023 				SAS_DPRINTK("ex %016llx->%016llx-?->%016llx "
1024 					    "diverges from subtractive "
1025 					    "boundary %016llx\n",
1026 					    SAS_ADDR(dev->sas_addr),
1027 					    SAS_ADDR(child->sas_addr),
1028 					    SAS_ADDR(s2),
1029 					    SAS_ADDR(sub_addr));
1030 
1031 				sas_ex_disable_port(child, s2);
1032 			}
1033 		}
1034 	}
1035 	return 0;
1036 }
1037 /**
1038  * sas_ex_discover_devices -- discover devices attached to this expander
1039  * dev: pointer to the expander domain device
1040  * single: if you want to do a single phy, else set to -1;
1041  *
1042  * Configure this expander for use with its devices and register the
1043  * devices of this expander.
1044  */
1045 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1046 {
1047 	struct expander_device *ex = &dev->ex_dev;
1048 	int i = 0, end = ex->num_phys;
1049 	int res = 0;
1050 
1051 	if (0 <= single && single < end) {
1052 		i = single;
1053 		end = i+1;
1054 	}
1055 
1056 	for ( ; i < end; i++) {
1057 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1058 
1059 		if (ex_phy->phy_state == PHY_VACANT ||
1060 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1061 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1062 			continue;
1063 
1064 		switch (ex_phy->linkrate) {
1065 		case SAS_PHY_DISABLED:
1066 		case SAS_PHY_RESET_PROBLEM:
1067 		case SAS_SATA_PORT_SELECTOR:
1068 			continue;
1069 		default:
1070 			res = sas_ex_discover_dev(dev, i);
1071 			if (res)
1072 				break;
1073 			continue;
1074 		}
1075 	}
1076 
1077 	if (!res)
1078 		sas_check_level_subtractive_boundary(dev);
1079 
1080 	return res;
1081 }
1082 
1083 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1084 {
1085 	struct expander_device *ex = &dev->ex_dev;
1086 	int i;
1087 	u8  *sub_sas_addr = NULL;
1088 
1089 	if (dev->dev_type != EDGE_DEV)
1090 		return 0;
1091 
1092 	for (i = 0; i < ex->num_phys; i++) {
1093 		struct ex_phy *phy = &ex->ex_phy[i];
1094 
1095 		if (phy->phy_state == PHY_VACANT ||
1096 		    phy->phy_state == PHY_NOT_PRESENT)
1097 			continue;
1098 
1099 		if ((phy->attached_dev_type == FANOUT_DEV ||
1100 		     phy->attached_dev_type == EDGE_DEV) &&
1101 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1102 
1103 			if (!sub_sas_addr)
1104 				sub_sas_addr = &phy->attached_sas_addr[0];
1105 			else if (SAS_ADDR(sub_sas_addr) !=
1106 				 SAS_ADDR(phy->attached_sas_addr)) {
1107 
1108 				SAS_DPRINTK("ex %016llx phy 0x%x "
1109 					    "diverges(%016llx) on subtractive "
1110 					    "boundary(%016llx). Disabled\n",
1111 					    SAS_ADDR(dev->sas_addr), i,
1112 					    SAS_ADDR(phy->attached_sas_addr),
1113 					    SAS_ADDR(sub_sas_addr));
1114 				sas_ex_disable_phy(dev, i);
1115 			}
1116 		}
1117 	}
1118 	return 0;
1119 }
1120 
1121 static void sas_print_parent_topology_bug(struct domain_device *child,
1122 						 struct ex_phy *parent_phy,
1123 						 struct ex_phy *child_phy)
1124 {
1125 	static const char ra_char[] = {
1126 		[DIRECT_ROUTING] = 'D',
1127 		[SUBTRACTIVE_ROUTING] = 'S',
1128 		[TABLE_ROUTING] = 'T',
1129 	};
1130 	static const char *ex_type[] = {
1131 		[EDGE_DEV] = "edge",
1132 		[FANOUT_DEV] = "fanout",
1133 	};
1134 	struct domain_device *parent = child->parent;
1135 
1136 	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx phy 0x%x "
1137 		   "has %c:%c routing link!\n",
1138 
1139 		   ex_type[parent->dev_type],
1140 		   SAS_ADDR(parent->sas_addr),
1141 		   parent_phy->phy_id,
1142 
1143 		   ex_type[child->dev_type],
1144 		   SAS_ADDR(child->sas_addr),
1145 		   child_phy->phy_id,
1146 
1147 		   ra_char[parent_phy->routing_attr],
1148 		   ra_char[child_phy->routing_attr]);
1149 }
1150 
1151 static int sas_check_eeds(struct domain_device *child,
1152 				 struct ex_phy *parent_phy,
1153 				 struct ex_phy *child_phy)
1154 {
1155 	int res = 0;
1156 	struct domain_device *parent = child->parent;
1157 
1158 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1159 		res = -ENODEV;
1160 		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
1161 			    "phy S:0x%x, while there is a fanout ex %016llx\n",
1162 			    SAS_ADDR(parent->sas_addr),
1163 			    parent_phy->phy_id,
1164 			    SAS_ADDR(child->sas_addr),
1165 			    child_phy->phy_id,
1166 			    SAS_ADDR(parent->port->disc.fanout_sas_addr));
1167 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1168 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1169 		       SAS_ADDR_SIZE);
1170 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1171 		       SAS_ADDR_SIZE);
1172 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1173 		    SAS_ADDR(parent->sas_addr)) ||
1174 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1175 		    SAS_ADDR(child->sas_addr)))
1176 		   &&
1177 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1178 		     SAS_ADDR(parent->sas_addr)) ||
1179 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1180 		     SAS_ADDR(child->sas_addr))))
1181 		;
1182 	else {
1183 		res = -ENODEV;
1184 		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
1185 			    "phy 0x%x link forms a third EEDS!\n",
1186 			    SAS_ADDR(parent->sas_addr),
1187 			    parent_phy->phy_id,
1188 			    SAS_ADDR(child->sas_addr),
1189 			    child_phy->phy_id);
1190 	}
1191 
1192 	return res;
1193 }
1194 
1195 /* Here we spill over 80 columns.  It is intentional.
1196  */
1197 static int sas_check_parent_topology(struct domain_device *child)
1198 {
1199 	struct expander_device *child_ex = &child->ex_dev;
1200 	struct expander_device *parent_ex;
1201 	int i;
1202 	int res = 0;
1203 
1204 	if (!child->parent)
1205 		return 0;
1206 
1207 	if (child->parent->dev_type != EDGE_DEV &&
1208 	    child->parent->dev_type != FANOUT_DEV)
1209 		return 0;
1210 
1211 	parent_ex = &child->parent->ex_dev;
1212 
1213 	for (i = 0; i < parent_ex->num_phys; i++) {
1214 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1215 		struct ex_phy *child_phy;
1216 
1217 		if (parent_phy->phy_state == PHY_VACANT ||
1218 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1219 			continue;
1220 
1221 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1222 			continue;
1223 
1224 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1225 
1226 		switch (child->parent->dev_type) {
1227 		case EDGE_DEV:
1228 			if (child->dev_type == FANOUT_DEV) {
1229 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1230 				    child_phy->routing_attr != TABLE_ROUTING) {
1231 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1232 					res = -ENODEV;
1233 				}
1234 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1235 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1236 					res = sas_check_eeds(child, parent_phy, child_phy);
1237 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1238 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1239 					res = -ENODEV;
1240 				}
1241 			} else if (parent_phy->routing_attr == TABLE_ROUTING &&
1242 				   child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1243 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1244 				res = -ENODEV;
1245 			}
1246 			break;
1247 		case FANOUT_DEV:
1248 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1249 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1250 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1251 				res = -ENODEV;
1252 			}
1253 			break;
1254 		default:
1255 			break;
1256 		}
1257 	}
1258 
1259 	return res;
1260 }
1261 
1262 #define RRI_REQ_SIZE  16
1263 #define RRI_RESP_SIZE 44
1264 
1265 static int sas_configure_present(struct domain_device *dev, int phy_id,
1266 				 u8 *sas_addr, int *index, int *present)
1267 {
1268 	int i, res = 0;
1269 	struct expander_device *ex = &dev->ex_dev;
1270 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1271 	u8 *rri_req;
1272 	u8 *rri_resp;
1273 
1274 	*present = 0;
1275 	*index = 0;
1276 
1277 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1278 	if (!rri_req)
1279 		return -ENOMEM;
1280 
1281 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1282 	if (!rri_resp) {
1283 		kfree(rri_req);
1284 		return -ENOMEM;
1285 	}
1286 
1287 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1288 	rri_req[9] = phy_id;
1289 
1290 	for (i = 0; i < ex->max_route_indexes ; i++) {
1291 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1292 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1293 				       RRI_RESP_SIZE);
1294 		if (res)
1295 			goto out;
1296 		res = rri_resp[2];
1297 		if (res == SMP_RESP_NO_INDEX) {
1298 			SAS_DPRINTK("overflow of indexes: dev %016llx "
1299 				    "phy 0x%x index 0x%x\n",
1300 				    SAS_ADDR(dev->sas_addr), phy_id, i);
1301 			goto out;
1302 		} else if (res != SMP_RESP_FUNC_ACC) {
1303 			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
1304 				    "result 0x%x\n", __func__,
1305 				    SAS_ADDR(dev->sas_addr), phy_id, i, res);
1306 			goto out;
1307 		}
1308 		if (SAS_ADDR(sas_addr) != 0) {
1309 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1310 				*index = i;
1311 				if ((rri_resp[12] & 0x80) == 0x80)
1312 					*present = 0;
1313 				else
1314 					*present = 1;
1315 				goto out;
1316 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1317 				*index = i;
1318 				*present = 0;
1319 				goto out;
1320 			}
1321 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1322 			   phy->last_da_index < i) {
1323 			phy->last_da_index = i;
1324 			*index = i;
1325 			*present = 0;
1326 			goto out;
1327 		}
1328 	}
1329 	res = -1;
1330 out:
1331 	kfree(rri_req);
1332 	kfree(rri_resp);
1333 	return res;
1334 }
1335 
1336 #define CRI_REQ_SIZE  44
1337 #define CRI_RESP_SIZE  8
1338 
1339 static int sas_configure_set(struct domain_device *dev, int phy_id,
1340 			     u8 *sas_addr, int index, int include)
1341 {
1342 	int res;
1343 	u8 *cri_req;
1344 	u8 *cri_resp;
1345 
1346 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1347 	if (!cri_req)
1348 		return -ENOMEM;
1349 
1350 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1351 	if (!cri_resp) {
1352 		kfree(cri_req);
1353 		return -ENOMEM;
1354 	}
1355 
1356 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1357 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1358 	cri_req[9] = phy_id;
1359 	if (SAS_ADDR(sas_addr) == 0 || !include)
1360 		cri_req[12] |= 0x80;
1361 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1362 
1363 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1364 			       CRI_RESP_SIZE);
1365 	if (res)
1366 		goto out;
1367 	res = cri_resp[2];
1368 	if (res == SMP_RESP_NO_INDEX) {
1369 		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
1370 			    "index 0x%x\n",
1371 			    SAS_ADDR(dev->sas_addr), phy_id, index);
1372 	}
1373 out:
1374 	kfree(cri_req);
1375 	kfree(cri_resp);
1376 	return res;
1377 }
1378 
1379 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1380 				    u8 *sas_addr, int include)
1381 {
1382 	int index;
1383 	int present;
1384 	int res;
1385 
1386 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1387 	if (res)
1388 		return res;
1389 	if (include ^ present)
1390 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1391 
1392 	return res;
1393 }
1394 
1395 /**
1396  * sas_configure_parent -- configure routing table of parent
1397  * parent: parent expander
1398  * child: child expander
1399  * sas_addr: SAS port identifier of device directly attached to child
1400  */
1401 static int sas_configure_parent(struct domain_device *parent,
1402 				struct domain_device *child,
1403 				u8 *sas_addr, int include)
1404 {
1405 	struct expander_device *ex_parent = &parent->ex_dev;
1406 	int res = 0;
1407 	int i;
1408 
1409 	if (parent->parent) {
1410 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1411 					   include);
1412 		if (res)
1413 			return res;
1414 	}
1415 
1416 	if (ex_parent->conf_route_table == 0) {
1417 		SAS_DPRINTK("ex %016llx has self-configuring routing table\n",
1418 			    SAS_ADDR(parent->sas_addr));
1419 		return 0;
1420 	}
1421 
1422 	for (i = 0; i < ex_parent->num_phys; i++) {
1423 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1424 
1425 		if ((phy->routing_attr == TABLE_ROUTING) &&
1426 		    (SAS_ADDR(phy->attached_sas_addr) ==
1427 		     SAS_ADDR(child->sas_addr))) {
1428 			res = sas_configure_phy(parent, i, sas_addr, include);
1429 			if (res)
1430 				return res;
1431 		}
1432 	}
1433 
1434 	return res;
1435 }
1436 
1437 /**
1438  * sas_configure_routing -- configure routing
1439  * dev: expander device
1440  * sas_addr: port identifier of device directly attached to the expander device
1441  */
1442 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1443 {
1444 	if (dev->parent)
1445 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1446 	return 0;
1447 }
1448 
1449 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1450 {
1451 	if (dev->parent)
1452 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1453 	return 0;
1454 }
1455 
1456 /**
1457  * sas_discover_expander -- expander discovery
1458  * @ex: pointer to expander domain device
1459  *
1460  * See comment in sas_discover_sata().
1461  */
1462 static int sas_discover_expander(struct domain_device *dev)
1463 {
1464 	int res;
1465 
1466 	res = sas_notify_lldd_dev_found(dev);
1467 	if (res)
1468 		return res;
1469 
1470 	res = sas_ex_general(dev);
1471 	if (res)
1472 		goto out_err;
1473 	res = sas_ex_manuf_info(dev);
1474 	if (res)
1475 		goto out_err;
1476 
1477 	res = sas_expander_discover(dev);
1478 	if (res) {
1479 		SAS_DPRINTK("expander %016llx discovery failed(0x%x)\n",
1480 			    SAS_ADDR(dev->sas_addr), res);
1481 		goto out_err;
1482 	}
1483 
1484 	sas_check_ex_subtractive_boundary(dev);
1485 	res = sas_check_parent_topology(dev);
1486 	if (res)
1487 		goto out_err;
1488 	return 0;
1489 out_err:
1490 	sas_notify_lldd_dev_gone(dev);
1491 	return res;
1492 }
1493 
1494 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1495 {
1496 	int res = 0;
1497 	struct domain_device *dev;
1498 
1499 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1500 		if (dev->dev_type == EDGE_DEV ||
1501 		    dev->dev_type == FANOUT_DEV) {
1502 			struct sas_expander_device *ex =
1503 				rphy_to_expander_device(dev->rphy);
1504 
1505 			if (level == ex->level)
1506 				res = sas_ex_discover_devices(dev, -1);
1507 			else if (level > 0)
1508 				res = sas_ex_discover_devices(port->port_dev, -1);
1509 
1510 		}
1511 	}
1512 
1513 	return res;
1514 }
1515 
1516 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1517 {
1518 	int res;
1519 	int level;
1520 
1521 	do {
1522 		level = port->disc.max_level;
1523 		res = sas_ex_level_discovery(port, level);
1524 		mb();
1525 	} while (level < port->disc.max_level);
1526 
1527 	return res;
1528 }
1529 
1530 int sas_discover_root_expander(struct domain_device *dev)
1531 {
1532 	int res;
1533 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1534 
1535 	res = sas_rphy_add(dev->rphy);
1536 	if (res)
1537 		goto out_err;
1538 
1539 	ex->level = dev->port->disc.max_level; /* 0 */
1540 	res = sas_discover_expander(dev);
1541 	if (res)
1542 		goto out_err2;
1543 
1544 	sas_ex_bfs_disc(dev->port);
1545 
1546 	return res;
1547 
1548 out_err2:
1549 	sas_rphy_remove(dev->rphy);
1550 out_err:
1551 	return res;
1552 }
1553 
1554 /* ---------- Domain revalidation ---------- */
1555 
1556 static int sas_get_phy_discover(struct domain_device *dev,
1557 				int phy_id, struct smp_resp *disc_resp)
1558 {
1559 	int res;
1560 	u8 *disc_req;
1561 
1562 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1563 	if (!disc_req)
1564 		return -ENOMEM;
1565 
1566 	disc_req[1] = SMP_DISCOVER;
1567 	disc_req[9] = phy_id;
1568 
1569 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1570 			       disc_resp, DISCOVER_RESP_SIZE);
1571 	if (res)
1572 		goto out;
1573 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1574 		res = disc_resp->result;
1575 		goto out;
1576 	}
1577 out:
1578 	kfree(disc_req);
1579 	return res;
1580 }
1581 
1582 static int sas_get_phy_change_count(struct domain_device *dev,
1583 				    int phy_id, int *pcc)
1584 {
1585 	int res;
1586 	struct smp_resp *disc_resp;
1587 
1588 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1589 	if (!disc_resp)
1590 		return -ENOMEM;
1591 
1592 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1593 	if (!res)
1594 		*pcc = disc_resp->disc.change_count;
1595 
1596 	kfree(disc_resp);
1597 	return res;
1598 }
1599 
1600 static int sas_get_phy_attached_sas_addr(struct domain_device *dev,
1601 					 int phy_id, u8 *attached_sas_addr)
1602 {
1603 	int res;
1604 	struct smp_resp *disc_resp;
1605 	struct discover_resp *dr;
1606 
1607 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1608 	if (!disc_resp)
1609 		return -ENOMEM;
1610 	dr = &disc_resp->disc;
1611 
1612 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1613 	if (!res) {
1614 		memcpy(attached_sas_addr,disc_resp->disc.attached_sas_addr,8);
1615 		if (dr->attached_dev_type == 0)
1616 			memset(attached_sas_addr, 0, 8);
1617 	}
1618 	kfree(disc_resp);
1619 	return res;
1620 }
1621 
1622 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1623 			      int from_phy, bool update)
1624 {
1625 	struct expander_device *ex = &dev->ex_dev;
1626 	int res = 0;
1627 	int i;
1628 
1629 	for (i = from_phy; i < ex->num_phys; i++) {
1630 		int phy_change_count = 0;
1631 
1632 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1633 		if (res)
1634 			goto out;
1635 		else if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1636 			if (update)
1637 				ex->ex_phy[i].phy_change_count =
1638 					phy_change_count;
1639 			*phy_id = i;
1640 			return 0;
1641 		}
1642 	}
1643 out:
1644 	return res;
1645 }
1646 
1647 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1648 {
1649 	int res;
1650 	u8  *rg_req;
1651 	struct smp_resp  *rg_resp;
1652 
1653 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1654 	if (!rg_req)
1655 		return -ENOMEM;
1656 
1657 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1658 	if (!rg_resp) {
1659 		kfree(rg_req);
1660 		return -ENOMEM;
1661 	}
1662 
1663 	rg_req[1] = SMP_REPORT_GENERAL;
1664 
1665 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1666 			       RG_RESP_SIZE);
1667 	if (res)
1668 		goto out;
1669 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1670 		res = rg_resp->result;
1671 		goto out;
1672 	}
1673 
1674 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1675 out:
1676 	kfree(rg_resp);
1677 	kfree(rg_req);
1678 	return res;
1679 }
1680 /**
1681  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1682  * @dev:domain device to be detect.
1683  * @src_dev: the device which originated BROADCAST(CHANGE).
1684  *
1685  * Add self-configuration expander suport. Suppose two expander cascading,
1686  * when the first level expander is self-configuring, hotplug the disks in
1687  * second level expander, BROADCAST(CHANGE) will not only be originated
1688  * in the second level expander, but also be originated in the first level
1689  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1690  * expander changed count in two level expanders will all increment at least
1691  * once, but the phy which chang count has changed is the source device which
1692  * we concerned.
1693  */
1694 
1695 static int sas_find_bcast_dev(struct domain_device *dev,
1696 			      struct domain_device **src_dev)
1697 {
1698 	struct expander_device *ex = &dev->ex_dev;
1699 	int ex_change_count = -1;
1700 	int phy_id = -1;
1701 	int res;
1702 	struct domain_device *ch;
1703 
1704 	res = sas_get_ex_change_count(dev, &ex_change_count);
1705 	if (res)
1706 		goto out;
1707 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1708 		/* Just detect if this expander phys phy change count changed,
1709 		* in order to determine if this expander originate BROADCAST,
1710 		* and do not update phy change count field in our structure.
1711 		*/
1712 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1713 		if (phy_id != -1) {
1714 			*src_dev = dev;
1715 			ex->ex_change_count = ex_change_count;
1716 			SAS_DPRINTK("Expander phy change count has changed\n");
1717 			return res;
1718 		} else
1719 			SAS_DPRINTK("Expander phys DID NOT change\n");
1720 	}
1721 	list_for_each_entry(ch, &ex->children, siblings) {
1722 		if (ch->dev_type == EDGE_DEV || ch->dev_type == FANOUT_DEV) {
1723 			res = sas_find_bcast_dev(ch, src_dev);
1724 			if (*src_dev)
1725 				return res;
1726 		}
1727 	}
1728 out:
1729 	return res;
1730 }
1731 
1732 static void sas_unregister_ex_tree(struct domain_device *dev)
1733 {
1734 	struct expander_device *ex = &dev->ex_dev;
1735 	struct domain_device *child, *n;
1736 
1737 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1738 		child->gone = 1;
1739 		if (child->dev_type == EDGE_DEV ||
1740 		    child->dev_type == FANOUT_DEV)
1741 			sas_unregister_ex_tree(child);
1742 		else
1743 			sas_unregister_dev(child);
1744 	}
1745 	sas_unregister_dev(dev);
1746 }
1747 
1748 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1749 					 int phy_id, bool last)
1750 {
1751 	struct expander_device *ex_dev = &parent->ex_dev;
1752 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1753 	struct domain_device *child, *n;
1754 	if (last) {
1755 		list_for_each_entry_safe(child, n,
1756 			&ex_dev->children, siblings) {
1757 			if (SAS_ADDR(child->sas_addr) ==
1758 			    SAS_ADDR(phy->attached_sas_addr)) {
1759 				child->gone = 1;
1760 				if (child->dev_type == EDGE_DEV ||
1761 				    child->dev_type == FANOUT_DEV)
1762 					sas_unregister_ex_tree(child);
1763 				else
1764 					sas_unregister_dev(child);
1765 				break;
1766 			}
1767 		}
1768 		parent->gone = 1;
1769 		sas_disable_routing(parent, phy->attached_sas_addr);
1770 	}
1771 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1772 	if (phy->port) {
1773 		sas_port_delete_phy(phy->port, phy->phy);
1774 		if (phy->port->num_phys == 0)
1775 			sas_port_delete(phy->port);
1776 		phy->port = NULL;
1777 	}
1778 }
1779 
1780 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1781 					  const int level)
1782 {
1783 	struct expander_device *ex_root = &root->ex_dev;
1784 	struct domain_device *child;
1785 	int res = 0;
1786 
1787 	list_for_each_entry(child, &ex_root->children, siblings) {
1788 		if (child->dev_type == EDGE_DEV ||
1789 		    child->dev_type == FANOUT_DEV) {
1790 			struct sas_expander_device *ex =
1791 				rphy_to_expander_device(child->rphy);
1792 
1793 			if (level > ex->level)
1794 				res = sas_discover_bfs_by_root_level(child,
1795 								     level);
1796 			else if (level == ex->level)
1797 				res = sas_ex_discover_devices(child, -1);
1798 		}
1799 	}
1800 	return res;
1801 }
1802 
1803 static int sas_discover_bfs_by_root(struct domain_device *dev)
1804 {
1805 	int res;
1806 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1807 	int level = ex->level+1;
1808 
1809 	res = sas_ex_discover_devices(dev, -1);
1810 	if (res)
1811 		goto out;
1812 	do {
1813 		res = sas_discover_bfs_by_root_level(dev, level);
1814 		mb();
1815 		level += 1;
1816 	} while (level <= dev->port->disc.max_level);
1817 out:
1818 	return res;
1819 }
1820 
1821 static int sas_discover_new(struct domain_device *dev, int phy_id)
1822 {
1823 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1824 	struct domain_device *child;
1825 	bool found = false;
1826 	int res, i;
1827 
1828 	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
1829 		    SAS_ADDR(dev->sas_addr), phy_id);
1830 	res = sas_ex_phy_discover(dev, phy_id);
1831 	if (res)
1832 		goto out;
1833 	/* to support the wide port inserted */
1834 	for (i = 0; i < dev->ex_dev.num_phys; i++) {
1835 		struct ex_phy *ex_phy_temp = &dev->ex_dev.ex_phy[i];
1836 		if (i == phy_id)
1837 			continue;
1838 		if (SAS_ADDR(ex_phy_temp->attached_sas_addr) ==
1839 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1840 			found = true;
1841 			break;
1842 		}
1843 	}
1844 	if (found) {
1845 		sas_ex_join_wide_port(dev, phy_id);
1846 		return 0;
1847 	}
1848 	res = sas_ex_discover_devices(dev, phy_id);
1849 	if (!res)
1850 		goto out;
1851 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1852 		if (SAS_ADDR(child->sas_addr) ==
1853 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1854 			if (child->dev_type == EDGE_DEV ||
1855 			    child->dev_type == FANOUT_DEV)
1856 				res = sas_discover_bfs_by_root(child);
1857 			break;
1858 		}
1859 	}
1860 out:
1861 	return res;
1862 }
1863 
1864 static int sas_rediscover_dev(struct domain_device *dev, int phy_id, bool last)
1865 {
1866 	struct expander_device *ex = &dev->ex_dev;
1867 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1868 	u8 attached_sas_addr[8];
1869 	int res;
1870 
1871 	res = sas_get_phy_attached_sas_addr(dev, phy_id, attached_sas_addr);
1872 	switch (res) {
1873 	case SMP_RESP_NO_PHY:
1874 		phy->phy_state = PHY_NOT_PRESENT;
1875 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1876 		goto out; break;
1877 	case SMP_RESP_PHY_VACANT:
1878 		phy->phy_state = PHY_VACANT;
1879 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1880 		goto out; break;
1881 	case SMP_RESP_FUNC_ACC:
1882 		break;
1883 	}
1884 
1885 	if (SAS_ADDR(attached_sas_addr) == 0) {
1886 		phy->phy_state = PHY_EMPTY;
1887 		sas_unregister_devs_sas_addr(dev, phy_id, last);
1888 	} else if (SAS_ADDR(attached_sas_addr) ==
1889 		   SAS_ADDR(phy->attached_sas_addr)) {
1890 		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter\n",
1891 			    SAS_ADDR(dev->sas_addr), phy_id);
1892 		sas_ex_phy_discover(dev, phy_id);
1893 	} else
1894 		res = sas_discover_new(dev, phy_id);
1895 out:
1896 	return res;
1897 }
1898 
1899 /**
1900  * sas_rediscover - revalidate the domain.
1901  * @dev:domain device to be detect.
1902  * @phy_id: the phy id will be detected.
1903  *
1904  * NOTE: this process _must_ quit (return) as soon as any connection
1905  * errors are encountered.  Connection recovery is done elsewhere.
1906  * Discover process only interrogates devices in order to discover the
1907  * domain.For plugging out, we un-register the device only when it is
1908  * the last phy in the port, for other phys in this port, we just delete it
1909  * from the port.For inserting, we do discovery when it is the
1910  * first phy,for other phys in this port, we add it to the port to
1911  * forming the wide-port.
1912  */
1913 static int sas_rediscover(struct domain_device *dev, const int phy_id)
1914 {
1915 	struct expander_device *ex = &dev->ex_dev;
1916 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
1917 	int res = 0;
1918 	int i;
1919 	bool last = true;	/* is this the last phy of the port */
1920 
1921 	SAS_DPRINTK("ex %016llx phy%d originated BROADCAST(CHANGE)\n",
1922 		    SAS_ADDR(dev->sas_addr), phy_id);
1923 
1924 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
1925 		for (i = 0; i < ex->num_phys; i++) {
1926 			struct ex_phy *phy = &ex->ex_phy[i];
1927 
1928 			if (i == phy_id)
1929 				continue;
1930 			if (SAS_ADDR(phy->attached_sas_addr) ==
1931 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
1932 				SAS_DPRINTK("phy%d part of wide port with "
1933 					    "phy%d\n", phy_id, i);
1934 				last = false;
1935 				break;
1936 			}
1937 		}
1938 		res = sas_rediscover_dev(dev, phy_id, last);
1939 	} else
1940 		res = sas_discover_new(dev, phy_id);
1941 	return res;
1942 }
1943 
1944 /**
1945  * sas_revalidate_domain -- revalidate the domain
1946  * @port: port to the domain of interest
1947  *
1948  * NOTE: this process _must_ quit (return) as soon as any connection
1949  * errors are encountered.  Connection recovery is done elsewhere.
1950  * Discover process only interrogates devices in order to discover the
1951  * domain.
1952  */
1953 int sas_ex_revalidate_domain(struct domain_device *port_dev)
1954 {
1955 	int res;
1956 	struct domain_device *dev = NULL;
1957 
1958 	res = sas_find_bcast_dev(port_dev, &dev);
1959 	if (res)
1960 		goto out;
1961 	if (dev) {
1962 		struct expander_device *ex = &dev->ex_dev;
1963 		int i = 0, phy_id;
1964 
1965 		do {
1966 			phy_id = -1;
1967 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
1968 			if (phy_id == -1)
1969 				break;
1970 			res = sas_rediscover(dev, phy_id);
1971 			i = phy_id + 1;
1972 		} while (i < ex->num_phys);
1973 	}
1974 out:
1975 	return res;
1976 }
1977 
1978 int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
1979 		    struct request *req)
1980 {
1981 	struct domain_device *dev;
1982 	int ret, type;
1983 	struct request *rsp = req->next_rq;
1984 
1985 	if (!rsp) {
1986 		printk("%s: space for a smp response is missing\n",
1987 		       __func__);
1988 		return -EINVAL;
1989 	}
1990 
1991 	/* no rphy means no smp target support (ie aic94xx host) */
1992 	if (!rphy)
1993 		return sas_smp_host_handler(shost, req, rsp);
1994 
1995 	type = rphy->identify.device_type;
1996 
1997 	if (type != SAS_EDGE_EXPANDER_DEVICE &&
1998 	    type != SAS_FANOUT_EXPANDER_DEVICE) {
1999 		printk("%s: can we send a smp request to a device?\n",
2000 		       __func__);
2001 		return -EINVAL;
2002 	}
2003 
2004 	dev = sas_find_dev_by_rphy(rphy);
2005 	if (!dev) {
2006 		printk("%s: fail to find a domain_device?\n", __func__);
2007 		return -EINVAL;
2008 	}
2009 
2010 	/* do we need to support multiple segments? */
2011 	if (req->bio->bi_vcnt > 1 || rsp->bio->bi_vcnt > 1) {
2012 		printk("%s: multiple segments req %u %u, rsp %u %u\n",
2013 		       __func__, req->bio->bi_vcnt, blk_rq_bytes(req),
2014 		       rsp->bio->bi_vcnt, blk_rq_bytes(rsp));
2015 		return -EINVAL;
2016 	}
2017 
2018 	ret = smp_execute_task(dev, bio_data(req->bio), blk_rq_bytes(req),
2019 			       bio_data(rsp->bio), blk_rq_bytes(rsp));
2020 	if (ret > 0) {
2021 		/* positive number is the untransferred residual */
2022 		rsp->resid_len = ret;
2023 		req->resid_len = 0;
2024 		ret = 0;
2025 	} else if (ret == 0) {
2026 		rsp->resid_len = 0;
2027 		req->resid_len = 0;
2028 	}
2029 
2030 	return ret;
2031 }
2032