1 /*
2  * Serial Attached SCSI (SAS) Expander discovery and configuration
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
22  *
23  */
24 
25 #include <linux/scatterlist.h>
26 #include <linux/blkdev.h>
27 #include <linux/slab.h>
28 
29 #include "sas_internal.h"
30 
31 #include <scsi/sas_ata.h>
32 #include <scsi/scsi_transport.h>
33 #include <scsi/scsi_transport_sas.h>
34 #include "../scsi_sas_internal.h"
35 
36 static int sas_discover_expander(struct domain_device *dev);
37 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
38 static int sas_configure_phy(struct domain_device *dev, int phy_id,
39 			     u8 *sas_addr, int include);
40 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
41 
42 /* ---------- SMP task management ---------- */
43 
44 static void smp_task_timedout(unsigned long _task)
45 {
46 	struct sas_task *task = (void *) _task;
47 	unsigned long flags;
48 
49 	spin_lock_irqsave(&task->task_state_lock, flags);
50 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
51 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
52 	spin_unlock_irqrestore(&task->task_state_lock, flags);
53 
54 	complete(&task->completion);
55 }
56 
57 static void smp_task_done(struct sas_task *task)
58 {
59 	if (!del_timer(&task->timer))
60 		return;
61 	complete(&task->completion);
62 }
63 
64 /* Give it some long enough timeout. In seconds. */
65 #define SMP_TIMEOUT 10
66 
67 static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
68 			    void *resp, int resp_size)
69 {
70 	int res, retry;
71 	struct sas_task *task = NULL;
72 	struct sas_internal *i =
73 		to_sas_internal(dev->port->ha->core.shost->transportt);
74 
75 	mutex_lock(&dev->ex_dev.cmd_mutex);
76 	for (retry = 0; retry < 3; retry++) {
77 		if (test_bit(SAS_DEV_GONE, &dev->state)) {
78 			res = -ECOMM;
79 			break;
80 		}
81 
82 		task = sas_alloc_task(GFP_KERNEL);
83 		if (!task) {
84 			res = -ENOMEM;
85 			break;
86 		}
87 		task->dev = dev;
88 		task->task_proto = dev->tproto;
89 		sg_init_one(&task->smp_task.smp_req, req, req_size);
90 		sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
91 
92 		task->task_done = smp_task_done;
93 
94 		task->timer.data = (unsigned long) task;
95 		task->timer.function = smp_task_timedout;
96 		task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
97 		add_timer(&task->timer);
98 
99 		res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
100 
101 		if (res) {
102 			del_timer(&task->timer);
103 			SAS_DPRINTK("executing SMP task failed:%d\n", res);
104 			break;
105 		}
106 
107 		wait_for_completion(&task->completion);
108 		res = -ECOMM;
109 		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
110 			SAS_DPRINTK("smp task timed out or aborted\n");
111 			i->dft->lldd_abort_task(task);
112 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
113 				SAS_DPRINTK("SMP task aborted and not done\n");
114 				break;
115 			}
116 		}
117 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
118 		    task->task_status.stat == SAM_STAT_GOOD) {
119 			res = 0;
120 			break;
121 		}
122 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
123 		    task->task_status.stat == SAS_DATA_UNDERRUN) {
124 			/* no error, but return the number of bytes of
125 			 * underrun */
126 			res = task->task_status.residual;
127 			break;
128 		}
129 		if (task->task_status.resp == SAS_TASK_COMPLETE &&
130 		    task->task_status.stat == SAS_DATA_OVERRUN) {
131 			res = -EMSGSIZE;
132 			break;
133 		}
134 		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
135 		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
136 			break;
137 		else {
138 			SAS_DPRINTK("%s: task to dev %016llx response: 0x%x "
139 				    "status 0x%x\n", __func__,
140 				    SAS_ADDR(dev->sas_addr),
141 				    task->task_status.resp,
142 				    task->task_status.stat);
143 			sas_free_task(task);
144 			task = NULL;
145 		}
146 	}
147 	mutex_unlock(&dev->ex_dev.cmd_mutex);
148 
149 	BUG_ON(retry == 3 && task != NULL);
150 	sas_free_task(task);
151 	return res;
152 }
153 
154 /* ---------- Allocations ---------- */
155 
156 static inline void *alloc_smp_req(int size)
157 {
158 	u8 *p = kzalloc(size, GFP_KERNEL);
159 	if (p)
160 		p[0] = SMP_REQUEST;
161 	return p;
162 }
163 
164 static inline void *alloc_smp_resp(int size)
165 {
166 	return kzalloc(size, GFP_KERNEL);
167 }
168 
169 static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
170 {
171 	switch (phy->routing_attr) {
172 	case TABLE_ROUTING:
173 		if (dev->ex_dev.t2t_supp)
174 			return 'U';
175 		else
176 			return 'T';
177 	case DIRECT_ROUTING:
178 		return 'D';
179 	case SUBTRACTIVE_ROUTING:
180 		return 'S';
181 	default:
182 		return '?';
183 	}
184 }
185 
186 static enum sas_dev_type to_dev_type(struct discover_resp *dr)
187 {
188 	/* This is detecting a failure to transmit initial dev to host
189 	 * FIS as described in section J.5 of sas-2 r16
190 	 */
191 	if (dr->attached_dev_type == NO_DEVICE && dr->attached_sata_dev &&
192 	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
193 		return SATA_PENDING;
194 	else
195 		return dr->attached_dev_type;
196 }
197 
198 static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
199 {
200 	enum sas_dev_type dev_type;
201 	enum sas_linkrate linkrate;
202 	u8 sas_addr[SAS_ADDR_SIZE];
203 	struct smp_resp *resp = rsp;
204 	struct discover_resp *dr = &resp->disc;
205 	struct sas_ha_struct *ha = dev->port->ha;
206 	struct expander_device *ex = &dev->ex_dev;
207 	struct ex_phy *phy = &ex->ex_phy[phy_id];
208 	struct sas_rphy *rphy = dev->rphy;
209 	bool new_phy = !phy->phy;
210 	char *type;
211 
212 	if (new_phy) {
213 		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
214 			return;
215 		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
216 
217 		/* FIXME: error_handling */
218 		BUG_ON(!phy->phy);
219 	}
220 
221 	switch (resp->result) {
222 	case SMP_RESP_PHY_VACANT:
223 		phy->phy_state = PHY_VACANT;
224 		break;
225 	default:
226 		phy->phy_state = PHY_NOT_PRESENT;
227 		break;
228 	case SMP_RESP_FUNC_ACC:
229 		phy->phy_state = PHY_EMPTY; /* do not know yet */
230 		break;
231 	}
232 
233 	/* check if anything important changed to squelch debug */
234 	dev_type = phy->attached_dev_type;
235 	linkrate  = phy->linkrate;
236 	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
237 
238 	phy->attached_dev_type = to_dev_type(dr);
239 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
240 		goto out;
241 	phy->phy_id = phy_id;
242 	phy->linkrate = dr->linkrate;
243 	phy->attached_sata_host = dr->attached_sata_host;
244 	phy->attached_sata_dev  = dr->attached_sata_dev;
245 	phy->attached_sata_ps   = dr->attached_sata_ps;
246 	phy->attached_iproto = dr->iproto << 1;
247 	phy->attached_tproto = dr->tproto << 1;
248 	/* help some expanders that fail to zero sas_address in the 'no
249 	 * device' case
250 	 */
251 	if (phy->attached_dev_type == NO_DEVICE ||
252 	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
253 		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
254 	else
255 		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
256 	phy->attached_phy_id = dr->attached_phy_id;
257 	phy->phy_change_count = dr->change_count;
258 	phy->routing_attr = dr->routing_attr;
259 	phy->virtual = dr->virtual;
260 	phy->last_da_index = -1;
261 
262 	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
263 	phy->phy->identify.device_type = dr->attached_dev_type;
264 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
265 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
266 	if (!phy->attached_tproto && dr->attached_sata_dev)
267 		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
268 	phy->phy->identify.phy_identifier = phy_id;
269 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
270 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
271 	phy->phy->minimum_linkrate = dr->pmin_linkrate;
272 	phy->phy->maximum_linkrate = dr->pmax_linkrate;
273 	phy->phy->negotiated_linkrate = phy->linkrate;
274 
275 	if (new_phy)
276 		if (sas_phy_add(phy->phy)) {
277 			sas_phy_free(phy->phy);
278 			return;
279 		}
280 
281  out:
282 	switch (phy->attached_dev_type) {
283 	case SATA_PENDING:
284 		type = "stp pending";
285 		break;
286 	case NO_DEVICE:
287 		type = "no device";
288 		break;
289 	case SAS_END_DEV:
290 		if (phy->attached_iproto) {
291 			if (phy->attached_tproto)
292 				type = "host+target";
293 			else
294 				type = "host";
295 		} else {
296 			if (dr->attached_sata_dev)
297 				type = "stp";
298 			else
299 				type = "ssp";
300 		}
301 		break;
302 	case EDGE_DEV:
303 	case FANOUT_DEV:
304 		type = "smp";
305 		break;
306 	default:
307 		type = "unknown";
308 	}
309 
310 	/* this routine is polled by libata error recovery so filter
311 	 * unimportant messages
312 	 */
313 	if (new_phy || phy->attached_dev_type != dev_type ||
314 	    phy->linkrate != linkrate ||
315 	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
316 		/* pass */;
317 	else
318 		return;
319 
320 	/* if the attached device type changed and ata_eh is active,
321 	 * make sure we run revalidation when eh completes (see:
322 	 * sas_enable_revalidation)
323 	 */
324 	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
325 		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
326 
327 	SAS_DPRINTK("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
328 		    test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
329 		    SAS_ADDR(dev->sas_addr), phy->phy_id,
330 		    sas_route_char(dev, phy), phy->linkrate,
331 		    SAS_ADDR(phy->attached_sas_addr), type);
332 }
333 
334 /* check if we have an existing attached ata device on this expander phy */
335 struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
336 {
337 	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
338 	struct domain_device *dev;
339 	struct sas_rphy *rphy;
340 
341 	if (!ex_phy->port)
342 		return NULL;
343 
344 	rphy = ex_phy->port->rphy;
345 	if (!rphy)
346 		return NULL;
347 
348 	dev = sas_find_dev_by_rphy(rphy);
349 
350 	if (dev && dev_is_sata(dev))
351 		return dev;
352 
353 	return NULL;
354 }
355 
356 #define DISCOVER_REQ_SIZE  16
357 #define DISCOVER_RESP_SIZE 56
358 
359 static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
360 				      u8 *disc_resp, int single)
361 {
362 	struct discover_resp *dr;
363 	int res;
364 
365 	disc_req[9] = single;
366 
367 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
368 			       disc_resp, DISCOVER_RESP_SIZE);
369 	if (res)
370 		return res;
371 	dr = &((struct smp_resp *)disc_resp)->disc;
372 	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
373 		sas_printk("Found loopback topology, just ignore it!\n");
374 		return 0;
375 	}
376 	sas_set_ex_phy(dev, single, disc_resp);
377 	return 0;
378 }
379 
380 int sas_ex_phy_discover(struct domain_device *dev, int single)
381 {
382 	struct expander_device *ex = &dev->ex_dev;
383 	int  res = 0;
384 	u8   *disc_req;
385 	u8   *disc_resp;
386 
387 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
388 	if (!disc_req)
389 		return -ENOMEM;
390 
391 	disc_resp = alloc_smp_req(DISCOVER_RESP_SIZE);
392 	if (!disc_resp) {
393 		kfree(disc_req);
394 		return -ENOMEM;
395 	}
396 
397 	disc_req[1] = SMP_DISCOVER;
398 
399 	if (0 <= single && single < ex->num_phys) {
400 		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
401 	} else {
402 		int i;
403 
404 		for (i = 0; i < ex->num_phys; i++) {
405 			res = sas_ex_phy_discover_helper(dev, disc_req,
406 							 disc_resp, i);
407 			if (res)
408 				goto out_err;
409 		}
410 	}
411 out_err:
412 	kfree(disc_resp);
413 	kfree(disc_req);
414 	return res;
415 }
416 
417 static int sas_expander_discover(struct domain_device *dev)
418 {
419 	struct expander_device *ex = &dev->ex_dev;
420 	int res = -ENOMEM;
421 
422 	ex->ex_phy = kzalloc(sizeof(*ex->ex_phy)*ex->num_phys, GFP_KERNEL);
423 	if (!ex->ex_phy)
424 		return -ENOMEM;
425 
426 	res = sas_ex_phy_discover(dev, -1);
427 	if (res)
428 		goto out_err;
429 
430 	return 0;
431  out_err:
432 	kfree(ex->ex_phy);
433 	ex->ex_phy = NULL;
434 	return res;
435 }
436 
437 #define MAX_EXPANDER_PHYS 128
438 
439 static void ex_assign_report_general(struct domain_device *dev,
440 					    struct smp_resp *resp)
441 {
442 	struct report_general_resp *rg = &resp->rg;
443 
444 	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
445 	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
446 	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
447 	dev->ex_dev.t2t_supp = rg->t2t_supp;
448 	dev->ex_dev.conf_route_table = rg->conf_route_table;
449 	dev->ex_dev.configuring = rg->configuring;
450 	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
451 }
452 
453 #define RG_REQ_SIZE   8
454 #define RG_RESP_SIZE 32
455 
456 static int sas_ex_general(struct domain_device *dev)
457 {
458 	u8 *rg_req;
459 	struct smp_resp *rg_resp;
460 	int res;
461 	int i;
462 
463 	rg_req = alloc_smp_req(RG_REQ_SIZE);
464 	if (!rg_req)
465 		return -ENOMEM;
466 
467 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
468 	if (!rg_resp) {
469 		kfree(rg_req);
470 		return -ENOMEM;
471 	}
472 
473 	rg_req[1] = SMP_REPORT_GENERAL;
474 
475 	for (i = 0; i < 5; i++) {
476 		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
477 				       RG_RESP_SIZE);
478 
479 		if (res) {
480 			SAS_DPRINTK("RG to ex %016llx failed:0x%x\n",
481 				    SAS_ADDR(dev->sas_addr), res);
482 			goto out;
483 		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
484 			SAS_DPRINTK("RG:ex %016llx returned SMP result:0x%x\n",
485 				    SAS_ADDR(dev->sas_addr), rg_resp->result);
486 			res = rg_resp->result;
487 			goto out;
488 		}
489 
490 		ex_assign_report_general(dev, rg_resp);
491 
492 		if (dev->ex_dev.configuring) {
493 			SAS_DPRINTK("RG: ex %llx self-configuring...\n",
494 				    SAS_ADDR(dev->sas_addr));
495 			schedule_timeout_interruptible(5*HZ);
496 		} else
497 			break;
498 	}
499 out:
500 	kfree(rg_req);
501 	kfree(rg_resp);
502 	return res;
503 }
504 
505 static void ex_assign_manuf_info(struct domain_device *dev, void
506 					*_mi_resp)
507 {
508 	u8 *mi_resp = _mi_resp;
509 	struct sas_rphy *rphy = dev->rphy;
510 	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
511 
512 	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
513 	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
514 	memcpy(edev->product_rev, mi_resp + 36,
515 	       SAS_EXPANDER_PRODUCT_REV_LEN);
516 
517 	if (mi_resp[8] & 1) {
518 		memcpy(edev->component_vendor_id, mi_resp + 40,
519 		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
520 		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
521 		edev->component_revision_id = mi_resp[50];
522 	}
523 }
524 
525 #define MI_REQ_SIZE   8
526 #define MI_RESP_SIZE 64
527 
528 static int sas_ex_manuf_info(struct domain_device *dev)
529 {
530 	u8 *mi_req;
531 	u8 *mi_resp;
532 	int res;
533 
534 	mi_req = alloc_smp_req(MI_REQ_SIZE);
535 	if (!mi_req)
536 		return -ENOMEM;
537 
538 	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
539 	if (!mi_resp) {
540 		kfree(mi_req);
541 		return -ENOMEM;
542 	}
543 
544 	mi_req[1] = SMP_REPORT_MANUF_INFO;
545 
546 	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
547 	if (res) {
548 		SAS_DPRINTK("MI: ex %016llx failed:0x%x\n",
549 			    SAS_ADDR(dev->sas_addr), res);
550 		goto out;
551 	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
552 		SAS_DPRINTK("MI ex %016llx returned SMP result:0x%x\n",
553 			    SAS_ADDR(dev->sas_addr), mi_resp[2]);
554 		goto out;
555 	}
556 
557 	ex_assign_manuf_info(dev, mi_resp);
558 out:
559 	kfree(mi_req);
560 	kfree(mi_resp);
561 	return res;
562 }
563 
564 #define PC_REQ_SIZE  44
565 #define PC_RESP_SIZE 8
566 
567 int sas_smp_phy_control(struct domain_device *dev, int phy_id,
568 			enum phy_func phy_func,
569 			struct sas_phy_linkrates *rates)
570 {
571 	u8 *pc_req;
572 	u8 *pc_resp;
573 	int res;
574 
575 	pc_req = alloc_smp_req(PC_REQ_SIZE);
576 	if (!pc_req)
577 		return -ENOMEM;
578 
579 	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
580 	if (!pc_resp) {
581 		kfree(pc_req);
582 		return -ENOMEM;
583 	}
584 
585 	pc_req[1] = SMP_PHY_CONTROL;
586 	pc_req[9] = phy_id;
587 	pc_req[10]= phy_func;
588 	if (rates) {
589 		pc_req[32] = rates->minimum_linkrate << 4;
590 		pc_req[33] = rates->maximum_linkrate << 4;
591 	}
592 
593 	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
594 
595 	kfree(pc_resp);
596 	kfree(pc_req);
597 	return res;
598 }
599 
600 static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
601 {
602 	struct expander_device *ex = &dev->ex_dev;
603 	struct ex_phy *phy = &ex->ex_phy[phy_id];
604 
605 	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
606 	phy->linkrate = SAS_PHY_DISABLED;
607 }
608 
609 static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
610 {
611 	struct expander_device *ex = &dev->ex_dev;
612 	int i;
613 
614 	for (i = 0; i < ex->num_phys; i++) {
615 		struct ex_phy *phy = &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) == SAS_ADDR(sas_addr))
622 			sas_ex_disable_phy(dev, i);
623 	}
624 }
625 
626 static int sas_dev_present_in_domain(struct asd_sas_port *port,
627 					    u8 *sas_addr)
628 {
629 	struct domain_device *dev;
630 
631 	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
632 		return 1;
633 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
634 		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
635 			return 1;
636 	}
637 	return 0;
638 }
639 
640 #define RPEL_REQ_SIZE	16
641 #define RPEL_RESP_SIZE	32
642 int sas_smp_get_phy_events(struct sas_phy *phy)
643 {
644 	int res;
645 	u8 *req;
646 	u8 *resp;
647 	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
648 	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
649 
650 	req = alloc_smp_req(RPEL_REQ_SIZE);
651 	if (!req)
652 		return -ENOMEM;
653 
654 	resp = alloc_smp_resp(RPEL_RESP_SIZE);
655 	if (!resp) {
656 		kfree(req);
657 		return -ENOMEM;
658 	}
659 
660 	req[1] = SMP_REPORT_PHY_ERR_LOG;
661 	req[9] = phy->number;
662 
663 	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
664 			            resp, RPEL_RESP_SIZE);
665 
666 	if (!res)
667 		goto out;
668 
669 	phy->invalid_dword_count = scsi_to_u32(&resp[12]);
670 	phy->running_disparity_error_count = scsi_to_u32(&resp[16]);
671 	phy->loss_of_dword_sync_count = scsi_to_u32(&resp[20]);
672 	phy->phy_reset_problem_count = scsi_to_u32(&resp[24]);
673 
674  out:
675 	kfree(resp);
676 	return res;
677 
678 }
679 
680 #ifdef CONFIG_SCSI_SAS_ATA
681 
682 #define RPS_REQ_SIZE  16
683 #define RPS_RESP_SIZE 60
684 
685 int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
686 			    struct smp_resp *rps_resp)
687 {
688 	int res;
689 	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
690 	u8 *resp = (u8 *)rps_resp;
691 
692 	if (!rps_req)
693 		return -ENOMEM;
694 
695 	rps_req[1] = SMP_REPORT_PHY_SATA;
696 	rps_req[9] = phy_id;
697 
698 	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
699 			            rps_resp, RPS_RESP_SIZE);
700 
701 	/* 0x34 is the FIS type for the D2H fis.  There's a potential
702 	 * standards cockup here.  sas-2 explicitly specifies the FIS
703 	 * should be encoded so that FIS type is in resp[24].
704 	 * However, some expanders endian reverse this.  Undo the
705 	 * reversal here */
706 	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
707 		int i;
708 
709 		for (i = 0; i < 5; i++) {
710 			int j = 24 + (i*4);
711 			u8 a, b;
712 			a = resp[j + 0];
713 			b = resp[j + 1];
714 			resp[j + 0] = resp[j + 3];
715 			resp[j + 1] = resp[j + 2];
716 			resp[j + 2] = b;
717 			resp[j + 3] = a;
718 		}
719 	}
720 
721 	kfree(rps_req);
722 	return res;
723 }
724 #endif
725 
726 static void sas_ex_get_linkrate(struct domain_device *parent,
727 				       struct domain_device *child,
728 				       struct ex_phy *parent_phy)
729 {
730 	struct expander_device *parent_ex = &parent->ex_dev;
731 	struct sas_port *port;
732 	int i;
733 
734 	child->pathways = 0;
735 
736 	port = parent_phy->port;
737 
738 	for (i = 0; i < parent_ex->num_phys; i++) {
739 		struct ex_phy *phy = &parent_ex->ex_phy[i];
740 
741 		if (phy->phy_state == PHY_VACANT ||
742 		    phy->phy_state == PHY_NOT_PRESENT)
743 			continue;
744 
745 		if (SAS_ADDR(phy->attached_sas_addr) ==
746 		    SAS_ADDR(child->sas_addr)) {
747 
748 			child->min_linkrate = min(parent->min_linkrate,
749 						  phy->linkrate);
750 			child->max_linkrate = max(parent->max_linkrate,
751 						  phy->linkrate);
752 			child->pathways++;
753 			sas_port_add_phy(port, phy->phy);
754 		}
755 	}
756 	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
757 	child->pathways = min(child->pathways, parent->pathways);
758 }
759 
760 static struct domain_device *sas_ex_discover_end_dev(
761 	struct domain_device *parent, int phy_id)
762 {
763 	struct expander_device *parent_ex = &parent->ex_dev;
764 	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
765 	struct domain_device *child = NULL;
766 	struct sas_rphy *rphy;
767 	int res;
768 
769 	if (phy->attached_sata_host || phy->attached_sata_ps)
770 		return NULL;
771 
772 	child = sas_alloc_device();
773 	if (!child)
774 		return NULL;
775 
776 	kref_get(&parent->kref);
777 	child->parent = parent;
778 	child->port   = parent->port;
779 	child->iproto = phy->attached_iproto;
780 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
781 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
782 	if (!phy->port) {
783 		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
784 		if (unlikely(!phy->port))
785 			goto out_err;
786 		if (unlikely(sas_port_add(phy->port) != 0)) {
787 			sas_port_free(phy->port);
788 			goto out_err;
789 		}
790 	}
791 	sas_ex_get_linkrate(parent, child, phy);
792 	sas_device_set_phy(child, phy->port);
793 
794 #ifdef CONFIG_SCSI_SAS_ATA
795 	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
796 		res = sas_get_ata_info(child, phy);
797 		if (res)
798 			goto out_free;
799 
800 		sas_init_dev(child);
801 		res = sas_ata_init(child);
802 		if (res)
803 			goto out_free;
804 		rphy = sas_end_device_alloc(phy->port);
805 		if (!rphy)
806 			goto out_free;
807 
808 		child->rphy = rphy;
809 		get_device(&rphy->dev);
810 
811 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
812 
813 		res = sas_discover_sata(child);
814 		if (res) {
815 			SAS_DPRINTK("sas_discover_sata() for device %16llx at "
816 				    "%016llx:0x%x returned 0x%x\n",
817 				    SAS_ADDR(child->sas_addr),
818 				    SAS_ADDR(parent->sas_addr), phy_id, res);
819 			goto out_list_del;
820 		}
821 	} else
822 #endif
823 	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
824 		child->dev_type = SAS_END_DEV;
825 		rphy = sas_end_device_alloc(phy->port);
826 		/* FIXME: error handling */
827 		if (unlikely(!rphy))
828 			goto out_free;
829 		child->tproto = phy->attached_tproto;
830 		sas_init_dev(child);
831 
832 		child->rphy = rphy;
833 		get_device(&rphy->dev);
834 		sas_fill_in_rphy(child, rphy);
835 
836 		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
837 
838 		res = sas_discover_end_dev(child);
839 		if (res) {
840 			SAS_DPRINTK("sas_discover_end_dev() for device %16llx "
841 				    "at %016llx:0x%x returned 0x%x\n",
842 				    SAS_ADDR(child->sas_addr),
843 				    SAS_ADDR(parent->sas_addr), phy_id, res);
844 			goto out_list_del;
845 		}
846 	} else {
847 		SAS_DPRINTK("target proto 0x%x at %016llx:0x%x not handled\n",
848 			    phy->attached_tproto, SAS_ADDR(parent->sas_addr),
849 			    phy_id);
850 		goto out_free;
851 	}
852 
853 	list_add_tail(&child->siblings, &parent_ex->children);
854 	return child;
855 
856  out_list_del:
857 	sas_rphy_free(child->rphy);
858 	list_del(&child->disco_list_node);
859 	spin_lock_irq(&parent->port->dev_list_lock);
860 	list_del(&child->dev_list_node);
861 	spin_unlock_irq(&parent->port->dev_list_lock);
862  out_free:
863 	sas_port_delete(phy->port);
864  out_err:
865 	phy->port = NULL;
866 	sas_put_device(child);
867 	return NULL;
868 }
869 
870 /* See if this phy is part of a wide port */
871 static int sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
872 {
873 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
874 	int i;
875 
876 	for (i = 0; i < parent->ex_dev.num_phys; i++) {
877 		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
878 
879 		if (ephy == phy)
880 			continue;
881 
882 		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
883 			    SAS_ADDR_SIZE) && ephy->port) {
884 			sas_port_add_phy(ephy->port, phy->phy);
885 			phy->port = ephy->port;
886 			phy->phy_state = PHY_DEVICE_DISCOVERED;
887 			return 0;
888 		}
889 	}
890 
891 	return -ENODEV;
892 }
893 
894 static struct domain_device *sas_ex_discover_expander(
895 	struct domain_device *parent, int phy_id)
896 {
897 	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
898 	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
899 	struct domain_device *child = NULL;
900 	struct sas_rphy *rphy;
901 	struct sas_expander_device *edev;
902 	struct asd_sas_port *port;
903 	int res;
904 
905 	if (phy->routing_attr == DIRECT_ROUTING) {
906 		SAS_DPRINTK("ex %016llx:0x%x:D <--> ex %016llx:0x%x is not "
907 			    "allowed\n",
908 			    SAS_ADDR(parent->sas_addr), phy_id,
909 			    SAS_ADDR(phy->attached_sas_addr),
910 			    phy->attached_phy_id);
911 		return NULL;
912 	}
913 	child = sas_alloc_device();
914 	if (!child)
915 		return NULL;
916 
917 	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
918 	/* FIXME: better error handling */
919 	BUG_ON(sas_port_add(phy->port) != 0);
920 
921 
922 	switch (phy->attached_dev_type) {
923 	case EDGE_DEV:
924 		rphy = sas_expander_alloc(phy->port,
925 					  SAS_EDGE_EXPANDER_DEVICE);
926 		break;
927 	case FANOUT_DEV:
928 		rphy = sas_expander_alloc(phy->port,
929 					  SAS_FANOUT_EXPANDER_DEVICE);
930 		break;
931 	default:
932 		rphy = NULL;	/* shut gcc up */
933 		BUG();
934 	}
935 	port = parent->port;
936 	child->rphy = rphy;
937 	get_device(&rphy->dev);
938 	edev = rphy_to_expander_device(rphy);
939 	child->dev_type = phy->attached_dev_type;
940 	kref_get(&parent->kref);
941 	child->parent = parent;
942 	child->port = port;
943 	child->iproto = phy->attached_iproto;
944 	child->tproto = phy->attached_tproto;
945 	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
946 	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
947 	sas_ex_get_linkrate(parent, child, phy);
948 	edev->level = parent_ex->level + 1;
949 	parent->port->disc.max_level = max(parent->port->disc.max_level,
950 					   edev->level);
951 	sas_init_dev(child);
952 	sas_fill_in_rphy(child, rphy);
953 	sas_rphy_add(rphy);
954 
955 	spin_lock_irq(&parent->port->dev_list_lock);
956 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
957 	spin_unlock_irq(&parent->port->dev_list_lock);
958 
959 	res = sas_discover_expander(child);
960 	if (res) {
961 		sas_rphy_delete(rphy);
962 		spin_lock_irq(&parent->port->dev_list_lock);
963 		list_del(&child->dev_list_node);
964 		spin_unlock_irq(&parent->port->dev_list_lock);
965 		sas_put_device(child);
966 		return NULL;
967 	}
968 	list_add_tail(&child->siblings, &parent->ex_dev.children);
969 	return child;
970 }
971 
972 static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
973 {
974 	struct expander_device *ex = &dev->ex_dev;
975 	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
976 	struct domain_device *child = NULL;
977 	int res = 0;
978 
979 	/* Phy state */
980 	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
981 		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
982 			res = sas_ex_phy_discover(dev, phy_id);
983 		if (res)
984 			return res;
985 	}
986 
987 	/* Parent and domain coherency */
988 	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
989 			     SAS_ADDR(dev->port->sas_addr))) {
990 		sas_add_parent_port(dev, phy_id);
991 		return 0;
992 	}
993 	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
994 			    SAS_ADDR(dev->parent->sas_addr))) {
995 		sas_add_parent_port(dev, phy_id);
996 		if (ex_phy->routing_attr == TABLE_ROUTING)
997 			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
998 		return 0;
999 	}
1000 
1001 	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
1002 		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
1003 
1004 	if (ex_phy->attached_dev_type == NO_DEVICE) {
1005 		if (ex_phy->routing_attr == DIRECT_ROUTING) {
1006 			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1007 			sas_configure_routing(dev, ex_phy->attached_sas_addr);
1008 		}
1009 		return 0;
1010 	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
1011 		return 0;
1012 
1013 	if (ex_phy->attached_dev_type != SAS_END_DEV &&
1014 	    ex_phy->attached_dev_type != FANOUT_DEV &&
1015 	    ex_phy->attached_dev_type != EDGE_DEV &&
1016 	    ex_phy->attached_dev_type != SATA_PENDING) {
1017 		SAS_DPRINTK("unknown device type(0x%x) attached to ex %016llx "
1018 			    "phy 0x%x\n", ex_phy->attached_dev_type,
1019 			    SAS_ADDR(dev->sas_addr),
1020 			    phy_id);
1021 		return 0;
1022 	}
1023 
1024 	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
1025 	if (res) {
1026 		SAS_DPRINTK("configure routing for dev %016llx "
1027 			    "reported 0x%x. Forgotten\n",
1028 			    SAS_ADDR(ex_phy->attached_sas_addr), res);
1029 		sas_disable_routing(dev, ex_phy->attached_sas_addr);
1030 		return res;
1031 	}
1032 
1033 	res = sas_ex_join_wide_port(dev, phy_id);
1034 	if (!res) {
1035 		SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
1036 			    phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
1037 		return res;
1038 	}
1039 
1040 	switch (ex_phy->attached_dev_type) {
1041 	case SAS_END_DEV:
1042 	case SATA_PENDING:
1043 		child = sas_ex_discover_end_dev(dev, phy_id);
1044 		break;
1045 	case FANOUT_DEV:
1046 		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
1047 			SAS_DPRINTK("second fanout expander %016llx phy 0x%x "
1048 				    "attached to ex %016llx phy 0x%x\n",
1049 				    SAS_ADDR(ex_phy->attached_sas_addr),
1050 				    ex_phy->attached_phy_id,
1051 				    SAS_ADDR(dev->sas_addr),
1052 				    phy_id);
1053 			sas_ex_disable_phy(dev, phy_id);
1054 			break;
1055 		} else
1056 			memcpy(dev->port->disc.fanout_sas_addr,
1057 			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
1058 		/* fallthrough */
1059 	case EDGE_DEV:
1060 		child = sas_ex_discover_expander(dev, phy_id);
1061 		break;
1062 	default:
1063 		break;
1064 	}
1065 
1066 	if (child) {
1067 		int i;
1068 
1069 		for (i = 0; i < ex->num_phys; i++) {
1070 			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
1071 			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
1072 				continue;
1073 			/*
1074 			 * Due to races, the phy might not get added to the
1075 			 * wide port, so we add the phy to the wide port here.
1076 			 */
1077 			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
1078 			    SAS_ADDR(child->sas_addr)) {
1079 				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
1080 				res = sas_ex_join_wide_port(dev, i);
1081 				if (!res)
1082 					SAS_DPRINTK("Attaching ex phy%d to wide port %016llx\n",
1083 						    i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
1084 
1085 			}
1086 		}
1087 	}
1088 
1089 	return res;
1090 }
1091 
1092 static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
1093 {
1094 	struct expander_device *ex = &dev->ex_dev;
1095 	int i;
1096 
1097 	for (i = 0; i < ex->num_phys; i++) {
1098 		struct ex_phy *phy = &ex->ex_phy[i];
1099 
1100 		if (phy->phy_state == PHY_VACANT ||
1101 		    phy->phy_state == PHY_NOT_PRESENT)
1102 			continue;
1103 
1104 		if ((phy->attached_dev_type == EDGE_DEV ||
1105 		     phy->attached_dev_type == FANOUT_DEV) &&
1106 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1107 
1108 			memcpy(sub_addr, phy->attached_sas_addr,SAS_ADDR_SIZE);
1109 
1110 			return 1;
1111 		}
1112 	}
1113 	return 0;
1114 }
1115 
1116 static int sas_check_level_subtractive_boundary(struct domain_device *dev)
1117 {
1118 	struct expander_device *ex = &dev->ex_dev;
1119 	struct domain_device *child;
1120 	u8 sub_addr[8] = {0, };
1121 
1122 	list_for_each_entry(child, &ex->children, siblings) {
1123 		if (child->dev_type != EDGE_DEV &&
1124 		    child->dev_type != FANOUT_DEV)
1125 			continue;
1126 		if (sub_addr[0] == 0) {
1127 			sas_find_sub_addr(child, sub_addr);
1128 			continue;
1129 		} else {
1130 			u8 s2[8];
1131 
1132 			if (sas_find_sub_addr(child, s2) &&
1133 			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
1134 
1135 				SAS_DPRINTK("ex %016llx->%016llx-?->%016llx "
1136 					    "diverges from subtractive "
1137 					    "boundary %016llx\n",
1138 					    SAS_ADDR(dev->sas_addr),
1139 					    SAS_ADDR(child->sas_addr),
1140 					    SAS_ADDR(s2),
1141 					    SAS_ADDR(sub_addr));
1142 
1143 				sas_ex_disable_port(child, s2);
1144 			}
1145 		}
1146 	}
1147 	return 0;
1148 }
1149 /**
1150  * sas_ex_discover_devices -- discover devices attached to this expander
1151  * dev: pointer to the expander domain device
1152  * single: if you want to do a single phy, else set to -1;
1153  *
1154  * Configure this expander for use with its devices and register the
1155  * devices of this expander.
1156  */
1157 static int sas_ex_discover_devices(struct domain_device *dev, int single)
1158 {
1159 	struct expander_device *ex = &dev->ex_dev;
1160 	int i = 0, end = ex->num_phys;
1161 	int res = 0;
1162 
1163 	if (0 <= single && single < end) {
1164 		i = single;
1165 		end = i+1;
1166 	}
1167 
1168 	for ( ; i < end; i++) {
1169 		struct ex_phy *ex_phy = &ex->ex_phy[i];
1170 
1171 		if (ex_phy->phy_state == PHY_VACANT ||
1172 		    ex_phy->phy_state == PHY_NOT_PRESENT ||
1173 		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
1174 			continue;
1175 
1176 		switch (ex_phy->linkrate) {
1177 		case SAS_PHY_DISABLED:
1178 		case SAS_PHY_RESET_PROBLEM:
1179 		case SAS_SATA_PORT_SELECTOR:
1180 			continue;
1181 		default:
1182 			res = sas_ex_discover_dev(dev, i);
1183 			if (res)
1184 				break;
1185 			continue;
1186 		}
1187 	}
1188 
1189 	if (!res)
1190 		sas_check_level_subtractive_boundary(dev);
1191 
1192 	return res;
1193 }
1194 
1195 static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
1196 {
1197 	struct expander_device *ex = &dev->ex_dev;
1198 	int i;
1199 	u8  *sub_sas_addr = NULL;
1200 
1201 	if (dev->dev_type != EDGE_DEV)
1202 		return 0;
1203 
1204 	for (i = 0; i < ex->num_phys; i++) {
1205 		struct ex_phy *phy = &ex->ex_phy[i];
1206 
1207 		if (phy->phy_state == PHY_VACANT ||
1208 		    phy->phy_state == PHY_NOT_PRESENT)
1209 			continue;
1210 
1211 		if ((phy->attached_dev_type == FANOUT_DEV ||
1212 		     phy->attached_dev_type == EDGE_DEV) &&
1213 		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
1214 
1215 			if (!sub_sas_addr)
1216 				sub_sas_addr = &phy->attached_sas_addr[0];
1217 			else if (SAS_ADDR(sub_sas_addr) !=
1218 				 SAS_ADDR(phy->attached_sas_addr)) {
1219 
1220 				SAS_DPRINTK("ex %016llx phy 0x%x "
1221 					    "diverges(%016llx) on subtractive "
1222 					    "boundary(%016llx). Disabled\n",
1223 					    SAS_ADDR(dev->sas_addr), i,
1224 					    SAS_ADDR(phy->attached_sas_addr),
1225 					    SAS_ADDR(sub_sas_addr));
1226 				sas_ex_disable_phy(dev, i);
1227 			}
1228 		}
1229 	}
1230 	return 0;
1231 }
1232 
1233 static void sas_print_parent_topology_bug(struct domain_device *child,
1234 						 struct ex_phy *parent_phy,
1235 						 struct ex_phy *child_phy)
1236 {
1237 	static const char *ex_type[] = {
1238 		[EDGE_DEV] = "edge",
1239 		[FANOUT_DEV] = "fanout",
1240 	};
1241 	struct domain_device *parent = child->parent;
1242 
1243 	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx "
1244 		   "phy 0x%x has %c:%c routing link!\n",
1245 
1246 		   ex_type[parent->dev_type],
1247 		   SAS_ADDR(parent->sas_addr),
1248 		   parent_phy->phy_id,
1249 
1250 		   ex_type[child->dev_type],
1251 		   SAS_ADDR(child->sas_addr),
1252 		   child_phy->phy_id,
1253 
1254 		   sas_route_char(parent, parent_phy),
1255 		   sas_route_char(child, child_phy));
1256 }
1257 
1258 static int sas_check_eeds(struct domain_device *child,
1259 				 struct ex_phy *parent_phy,
1260 				 struct ex_phy *child_phy)
1261 {
1262 	int res = 0;
1263 	struct domain_device *parent = child->parent;
1264 
1265 	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
1266 		res = -ENODEV;
1267 		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
1268 			    "phy S:0x%x, while there is a fanout ex %016llx\n",
1269 			    SAS_ADDR(parent->sas_addr),
1270 			    parent_phy->phy_id,
1271 			    SAS_ADDR(child->sas_addr),
1272 			    child_phy->phy_id,
1273 			    SAS_ADDR(parent->port->disc.fanout_sas_addr));
1274 	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
1275 		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
1276 		       SAS_ADDR_SIZE);
1277 		memcpy(parent->port->disc.eeds_b, child->sas_addr,
1278 		       SAS_ADDR_SIZE);
1279 	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
1280 		    SAS_ADDR(parent->sas_addr)) ||
1281 		   (SAS_ADDR(parent->port->disc.eeds_a) ==
1282 		    SAS_ADDR(child->sas_addr)))
1283 		   &&
1284 		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
1285 		     SAS_ADDR(parent->sas_addr)) ||
1286 		    (SAS_ADDR(parent->port->disc.eeds_b) ==
1287 		     SAS_ADDR(child->sas_addr))))
1288 		;
1289 	else {
1290 		res = -ENODEV;
1291 		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
1292 			    "phy 0x%x link forms a third EEDS!\n",
1293 			    SAS_ADDR(parent->sas_addr),
1294 			    parent_phy->phy_id,
1295 			    SAS_ADDR(child->sas_addr),
1296 			    child_phy->phy_id);
1297 	}
1298 
1299 	return res;
1300 }
1301 
1302 /* Here we spill over 80 columns.  It is intentional.
1303  */
1304 static int sas_check_parent_topology(struct domain_device *child)
1305 {
1306 	struct expander_device *child_ex = &child->ex_dev;
1307 	struct expander_device *parent_ex;
1308 	int i;
1309 	int res = 0;
1310 
1311 	if (!child->parent)
1312 		return 0;
1313 
1314 	if (child->parent->dev_type != EDGE_DEV &&
1315 	    child->parent->dev_type != FANOUT_DEV)
1316 		return 0;
1317 
1318 	parent_ex = &child->parent->ex_dev;
1319 
1320 	for (i = 0; i < parent_ex->num_phys; i++) {
1321 		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
1322 		struct ex_phy *child_phy;
1323 
1324 		if (parent_phy->phy_state == PHY_VACANT ||
1325 		    parent_phy->phy_state == PHY_NOT_PRESENT)
1326 			continue;
1327 
1328 		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
1329 			continue;
1330 
1331 		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
1332 
1333 		switch (child->parent->dev_type) {
1334 		case EDGE_DEV:
1335 			if (child->dev_type == FANOUT_DEV) {
1336 				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
1337 				    child_phy->routing_attr != TABLE_ROUTING) {
1338 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1339 					res = -ENODEV;
1340 				}
1341 			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1342 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
1343 					res = sas_check_eeds(child, parent_phy, child_phy);
1344 				} else if (child_phy->routing_attr != TABLE_ROUTING) {
1345 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1346 					res = -ENODEV;
1347 				}
1348 			} else if (parent_phy->routing_attr == TABLE_ROUTING) {
1349 				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING ||
1350 				    (child_phy->routing_attr == TABLE_ROUTING &&
1351 				     child_ex->t2t_supp && parent_ex->t2t_supp)) {
1352 					/* All good */;
1353 				} else {
1354 					sas_print_parent_topology_bug(child, parent_phy, child_phy);
1355 					res = -ENODEV;
1356 				}
1357 			}
1358 			break;
1359 		case FANOUT_DEV:
1360 			if (parent_phy->routing_attr != TABLE_ROUTING ||
1361 			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
1362 				sas_print_parent_topology_bug(child, parent_phy, child_phy);
1363 				res = -ENODEV;
1364 			}
1365 			break;
1366 		default:
1367 			break;
1368 		}
1369 	}
1370 
1371 	return res;
1372 }
1373 
1374 #define RRI_REQ_SIZE  16
1375 #define RRI_RESP_SIZE 44
1376 
1377 static int sas_configure_present(struct domain_device *dev, int phy_id,
1378 				 u8 *sas_addr, int *index, int *present)
1379 {
1380 	int i, res = 0;
1381 	struct expander_device *ex = &dev->ex_dev;
1382 	struct ex_phy *phy = &ex->ex_phy[phy_id];
1383 	u8 *rri_req;
1384 	u8 *rri_resp;
1385 
1386 	*present = 0;
1387 	*index = 0;
1388 
1389 	rri_req = alloc_smp_req(RRI_REQ_SIZE);
1390 	if (!rri_req)
1391 		return -ENOMEM;
1392 
1393 	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
1394 	if (!rri_resp) {
1395 		kfree(rri_req);
1396 		return -ENOMEM;
1397 	}
1398 
1399 	rri_req[1] = SMP_REPORT_ROUTE_INFO;
1400 	rri_req[9] = phy_id;
1401 
1402 	for (i = 0; i < ex->max_route_indexes ; i++) {
1403 		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
1404 		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
1405 				       RRI_RESP_SIZE);
1406 		if (res)
1407 			goto out;
1408 		res = rri_resp[2];
1409 		if (res == SMP_RESP_NO_INDEX) {
1410 			SAS_DPRINTK("overflow of indexes: dev %016llx "
1411 				    "phy 0x%x index 0x%x\n",
1412 				    SAS_ADDR(dev->sas_addr), phy_id, i);
1413 			goto out;
1414 		} else if (res != SMP_RESP_FUNC_ACC) {
1415 			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
1416 				    "result 0x%x\n", __func__,
1417 				    SAS_ADDR(dev->sas_addr), phy_id, i, res);
1418 			goto out;
1419 		}
1420 		if (SAS_ADDR(sas_addr) != 0) {
1421 			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
1422 				*index = i;
1423 				if ((rri_resp[12] & 0x80) == 0x80)
1424 					*present = 0;
1425 				else
1426 					*present = 1;
1427 				goto out;
1428 			} else if (SAS_ADDR(rri_resp+16) == 0) {
1429 				*index = i;
1430 				*present = 0;
1431 				goto out;
1432 			}
1433 		} else if (SAS_ADDR(rri_resp+16) == 0 &&
1434 			   phy->last_da_index < i) {
1435 			phy->last_da_index = i;
1436 			*index = i;
1437 			*present = 0;
1438 			goto out;
1439 		}
1440 	}
1441 	res = -1;
1442 out:
1443 	kfree(rri_req);
1444 	kfree(rri_resp);
1445 	return res;
1446 }
1447 
1448 #define CRI_REQ_SIZE  44
1449 #define CRI_RESP_SIZE  8
1450 
1451 static int sas_configure_set(struct domain_device *dev, int phy_id,
1452 			     u8 *sas_addr, int index, int include)
1453 {
1454 	int res;
1455 	u8 *cri_req;
1456 	u8 *cri_resp;
1457 
1458 	cri_req = alloc_smp_req(CRI_REQ_SIZE);
1459 	if (!cri_req)
1460 		return -ENOMEM;
1461 
1462 	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
1463 	if (!cri_resp) {
1464 		kfree(cri_req);
1465 		return -ENOMEM;
1466 	}
1467 
1468 	cri_req[1] = SMP_CONF_ROUTE_INFO;
1469 	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
1470 	cri_req[9] = phy_id;
1471 	if (SAS_ADDR(sas_addr) == 0 || !include)
1472 		cri_req[12] |= 0x80;
1473 	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
1474 
1475 	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
1476 			       CRI_RESP_SIZE);
1477 	if (res)
1478 		goto out;
1479 	res = cri_resp[2];
1480 	if (res == SMP_RESP_NO_INDEX) {
1481 		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
1482 			    "index 0x%x\n",
1483 			    SAS_ADDR(dev->sas_addr), phy_id, index);
1484 	}
1485 out:
1486 	kfree(cri_req);
1487 	kfree(cri_resp);
1488 	return res;
1489 }
1490 
1491 static int sas_configure_phy(struct domain_device *dev, int phy_id,
1492 				    u8 *sas_addr, int include)
1493 {
1494 	int index;
1495 	int present;
1496 	int res;
1497 
1498 	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
1499 	if (res)
1500 		return res;
1501 	if (include ^ present)
1502 		return sas_configure_set(dev, phy_id, sas_addr, index,include);
1503 
1504 	return res;
1505 }
1506 
1507 /**
1508  * sas_configure_parent -- configure routing table of parent
1509  * parent: parent expander
1510  * child: child expander
1511  * sas_addr: SAS port identifier of device directly attached to child
1512  */
1513 static int sas_configure_parent(struct domain_device *parent,
1514 				struct domain_device *child,
1515 				u8 *sas_addr, int include)
1516 {
1517 	struct expander_device *ex_parent = &parent->ex_dev;
1518 	int res = 0;
1519 	int i;
1520 
1521 	if (parent->parent) {
1522 		res = sas_configure_parent(parent->parent, parent, sas_addr,
1523 					   include);
1524 		if (res)
1525 			return res;
1526 	}
1527 
1528 	if (ex_parent->conf_route_table == 0) {
1529 		SAS_DPRINTK("ex %016llx has self-configuring routing table\n",
1530 			    SAS_ADDR(parent->sas_addr));
1531 		return 0;
1532 	}
1533 
1534 	for (i = 0; i < ex_parent->num_phys; i++) {
1535 		struct ex_phy *phy = &ex_parent->ex_phy[i];
1536 
1537 		if ((phy->routing_attr == TABLE_ROUTING) &&
1538 		    (SAS_ADDR(phy->attached_sas_addr) ==
1539 		     SAS_ADDR(child->sas_addr))) {
1540 			res = sas_configure_phy(parent, i, sas_addr, include);
1541 			if (res)
1542 				return res;
1543 		}
1544 	}
1545 
1546 	return res;
1547 }
1548 
1549 /**
1550  * sas_configure_routing -- configure routing
1551  * dev: expander device
1552  * sas_addr: port identifier of device directly attached to the expander device
1553  */
1554 static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
1555 {
1556 	if (dev->parent)
1557 		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
1558 	return 0;
1559 }
1560 
1561 static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
1562 {
1563 	if (dev->parent)
1564 		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
1565 	return 0;
1566 }
1567 
1568 /**
1569  * sas_discover_expander -- expander discovery
1570  * @ex: pointer to expander domain device
1571  *
1572  * See comment in sas_discover_sata().
1573  */
1574 static int sas_discover_expander(struct domain_device *dev)
1575 {
1576 	int res;
1577 
1578 	res = sas_notify_lldd_dev_found(dev);
1579 	if (res)
1580 		return res;
1581 
1582 	res = sas_ex_general(dev);
1583 	if (res)
1584 		goto out_err;
1585 	res = sas_ex_manuf_info(dev);
1586 	if (res)
1587 		goto out_err;
1588 
1589 	res = sas_expander_discover(dev);
1590 	if (res) {
1591 		SAS_DPRINTK("expander %016llx discovery failed(0x%x)\n",
1592 			    SAS_ADDR(dev->sas_addr), res);
1593 		goto out_err;
1594 	}
1595 
1596 	sas_check_ex_subtractive_boundary(dev);
1597 	res = sas_check_parent_topology(dev);
1598 	if (res)
1599 		goto out_err;
1600 	return 0;
1601 out_err:
1602 	sas_notify_lldd_dev_gone(dev);
1603 	return res;
1604 }
1605 
1606 static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
1607 {
1608 	int res = 0;
1609 	struct domain_device *dev;
1610 
1611 	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
1612 		if (dev->dev_type == EDGE_DEV ||
1613 		    dev->dev_type == FANOUT_DEV) {
1614 			struct sas_expander_device *ex =
1615 				rphy_to_expander_device(dev->rphy);
1616 
1617 			if (level == ex->level)
1618 				res = sas_ex_discover_devices(dev, -1);
1619 			else if (level > 0)
1620 				res = sas_ex_discover_devices(port->port_dev, -1);
1621 
1622 		}
1623 	}
1624 
1625 	return res;
1626 }
1627 
1628 static int sas_ex_bfs_disc(struct asd_sas_port *port)
1629 {
1630 	int res;
1631 	int level;
1632 
1633 	do {
1634 		level = port->disc.max_level;
1635 		res = sas_ex_level_discovery(port, level);
1636 		mb();
1637 	} while (level < port->disc.max_level);
1638 
1639 	return res;
1640 }
1641 
1642 int sas_discover_root_expander(struct domain_device *dev)
1643 {
1644 	int res;
1645 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1646 
1647 	res = sas_rphy_add(dev->rphy);
1648 	if (res)
1649 		goto out_err;
1650 
1651 	ex->level = dev->port->disc.max_level; /* 0 */
1652 	res = sas_discover_expander(dev);
1653 	if (res)
1654 		goto out_err2;
1655 
1656 	sas_ex_bfs_disc(dev->port);
1657 
1658 	return res;
1659 
1660 out_err2:
1661 	sas_rphy_remove(dev->rphy);
1662 out_err:
1663 	return res;
1664 }
1665 
1666 /* ---------- Domain revalidation ---------- */
1667 
1668 static int sas_get_phy_discover(struct domain_device *dev,
1669 				int phy_id, struct smp_resp *disc_resp)
1670 {
1671 	int res;
1672 	u8 *disc_req;
1673 
1674 	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
1675 	if (!disc_req)
1676 		return -ENOMEM;
1677 
1678 	disc_req[1] = SMP_DISCOVER;
1679 	disc_req[9] = phy_id;
1680 
1681 	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
1682 			       disc_resp, DISCOVER_RESP_SIZE);
1683 	if (res)
1684 		goto out;
1685 	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
1686 		res = disc_resp->result;
1687 		goto out;
1688 	}
1689 out:
1690 	kfree(disc_req);
1691 	return res;
1692 }
1693 
1694 static int sas_get_phy_change_count(struct domain_device *dev,
1695 				    int phy_id, int *pcc)
1696 {
1697 	int res;
1698 	struct smp_resp *disc_resp;
1699 
1700 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1701 	if (!disc_resp)
1702 		return -ENOMEM;
1703 
1704 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1705 	if (!res)
1706 		*pcc = disc_resp->disc.change_count;
1707 
1708 	kfree(disc_resp);
1709 	return res;
1710 }
1711 
1712 static int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
1713 				    u8 *sas_addr, enum sas_dev_type *type)
1714 {
1715 	int res;
1716 	struct smp_resp *disc_resp;
1717 	struct discover_resp *dr;
1718 
1719 	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
1720 	if (!disc_resp)
1721 		return -ENOMEM;
1722 	dr = &disc_resp->disc;
1723 
1724 	res = sas_get_phy_discover(dev, phy_id, disc_resp);
1725 	if (res == 0) {
1726 		memcpy(sas_addr, disc_resp->disc.attached_sas_addr, 8);
1727 		*type = to_dev_type(dr);
1728 		if (*type == 0)
1729 			memset(sas_addr, 0, 8);
1730 	}
1731 	kfree(disc_resp);
1732 	return res;
1733 }
1734 
1735 static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
1736 			      int from_phy, bool update)
1737 {
1738 	struct expander_device *ex = &dev->ex_dev;
1739 	int res = 0;
1740 	int i;
1741 
1742 	for (i = from_phy; i < ex->num_phys; i++) {
1743 		int phy_change_count = 0;
1744 
1745 		res = sas_get_phy_change_count(dev, i, &phy_change_count);
1746 		switch (res) {
1747 		case SMP_RESP_PHY_VACANT:
1748 		case SMP_RESP_NO_PHY:
1749 			continue;
1750 		case SMP_RESP_FUNC_ACC:
1751 			break;
1752 		default:
1753 			return res;
1754 		}
1755 
1756 		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
1757 			if (update)
1758 				ex->ex_phy[i].phy_change_count =
1759 					phy_change_count;
1760 			*phy_id = i;
1761 			return 0;
1762 		}
1763 	}
1764 	return 0;
1765 }
1766 
1767 static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
1768 {
1769 	int res;
1770 	u8  *rg_req;
1771 	struct smp_resp  *rg_resp;
1772 
1773 	rg_req = alloc_smp_req(RG_REQ_SIZE);
1774 	if (!rg_req)
1775 		return -ENOMEM;
1776 
1777 	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
1778 	if (!rg_resp) {
1779 		kfree(rg_req);
1780 		return -ENOMEM;
1781 	}
1782 
1783 	rg_req[1] = SMP_REPORT_GENERAL;
1784 
1785 	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
1786 			       RG_RESP_SIZE);
1787 	if (res)
1788 		goto out;
1789 	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
1790 		res = rg_resp->result;
1791 		goto out;
1792 	}
1793 
1794 	*ecc = be16_to_cpu(rg_resp->rg.change_count);
1795 out:
1796 	kfree(rg_resp);
1797 	kfree(rg_req);
1798 	return res;
1799 }
1800 /**
1801  * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
1802  * @dev:domain device to be detect.
1803  * @src_dev: the device which originated BROADCAST(CHANGE).
1804  *
1805  * Add self-configuration expander suport. Suppose two expander cascading,
1806  * when the first level expander is self-configuring, hotplug the disks in
1807  * second level expander, BROADCAST(CHANGE) will not only be originated
1808  * in the second level expander, but also be originated in the first level
1809  * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
1810  * expander changed count in two level expanders will all increment at least
1811  * once, but the phy which chang count has changed is the source device which
1812  * we concerned.
1813  */
1814 
1815 static int sas_find_bcast_dev(struct domain_device *dev,
1816 			      struct domain_device **src_dev)
1817 {
1818 	struct expander_device *ex = &dev->ex_dev;
1819 	int ex_change_count = -1;
1820 	int phy_id = -1;
1821 	int res;
1822 	struct domain_device *ch;
1823 
1824 	res = sas_get_ex_change_count(dev, &ex_change_count);
1825 	if (res)
1826 		goto out;
1827 	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
1828 		/* Just detect if this expander phys phy change count changed,
1829 		* in order to determine if this expander originate BROADCAST,
1830 		* and do not update phy change count field in our structure.
1831 		*/
1832 		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
1833 		if (phy_id != -1) {
1834 			*src_dev = dev;
1835 			ex->ex_change_count = ex_change_count;
1836 			SAS_DPRINTK("Expander phy change count has changed\n");
1837 			return res;
1838 		} else
1839 			SAS_DPRINTK("Expander phys DID NOT change\n");
1840 	}
1841 	list_for_each_entry(ch, &ex->children, siblings) {
1842 		if (ch->dev_type == EDGE_DEV || ch->dev_type == FANOUT_DEV) {
1843 			res = sas_find_bcast_dev(ch, src_dev);
1844 			if (*src_dev)
1845 				return res;
1846 		}
1847 	}
1848 out:
1849 	return res;
1850 }
1851 
1852 static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
1853 {
1854 	struct expander_device *ex = &dev->ex_dev;
1855 	struct domain_device *child, *n;
1856 
1857 	list_for_each_entry_safe(child, n, &ex->children, siblings) {
1858 		set_bit(SAS_DEV_GONE, &child->state);
1859 		if (child->dev_type == EDGE_DEV ||
1860 		    child->dev_type == FANOUT_DEV)
1861 			sas_unregister_ex_tree(port, child);
1862 		else
1863 			sas_unregister_dev(port, child);
1864 	}
1865 	sas_unregister_dev(port, dev);
1866 }
1867 
1868 static void sas_unregister_devs_sas_addr(struct domain_device *parent,
1869 					 int phy_id, bool last)
1870 {
1871 	struct expander_device *ex_dev = &parent->ex_dev;
1872 	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
1873 	struct domain_device *child, *n, *found = NULL;
1874 	if (last) {
1875 		list_for_each_entry_safe(child, n,
1876 			&ex_dev->children, siblings) {
1877 			if (SAS_ADDR(child->sas_addr) ==
1878 			    SAS_ADDR(phy->attached_sas_addr)) {
1879 				set_bit(SAS_DEV_GONE, &child->state);
1880 				if (child->dev_type == EDGE_DEV ||
1881 				    child->dev_type == FANOUT_DEV)
1882 					sas_unregister_ex_tree(parent->port, child);
1883 				else
1884 					sas_unregister_dev(parent->port, child);
1885 				found = child;
1886 				break;
1887 			}
1888 		}
1889 		sas_disable_routing(parent, phy->attached_sas_addr);
1890 	}
1891 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
1892 	if (phy->port) {
1893 		sas_port_delete_phy(phy->port, phy->phy);
1894 		sas_device_set_phy(found, phy->port);
1895 		if (phy->port->num_phys == 0)
1896 			sas_port_delete(phy->port);
1897 		phy->port = NULL;
1898 	}
1899 }
1900 
1901 static int sas_discover_bfs_by_root_level(struct domain_device *root,
1902 					  const int level)
1903 {
1904 	struct expander_device *ex_root = &root->ex_dev;
1905 	struct domain_device *child;
1906 	int res = 0;
1907 
1908 	list_for_each_entry(child, &ex_root->children, siblings) {
1909 		if (child->dev_type == EDGE_DEV ||
1910 		    child->dev_type == FANOUT_DEV) {
1911 			struct sas_expander_device *ex =
1912 				rphy_to_expander_device(child->rphy);
1913 
1914 			if (level > ex->level)
1915 				res = sas_discover_bfs_by_root_level(child,
1916 								     level);
1917 			else if (level == ex->level)
1918 				res = sas_ex_discover_devices(child, -1);
1919 		}
1920 	}
1921 	return res;
1922 }
1923 
1924 static int sas_discover_bfs_by_root(struct domain_device *dev)
1925 {
1926 	int res;
1927 	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
1928 	int level = ex->level+1;
1929 
1930 	res = sas_ex_discover_devices(dev, -1);
1931 	if (res)
1932 		goto out;
1933 	do {
1934 		res = sas_discover_bfs_by_root_level(dev, level);
1935 		mb();
1936 		level += 1;
1937 	} while (level <= dev->port->disc.max_level);
1938 out:
1939 	return res;
1940 }
1941 
1942 static int sas_discover_new(struct domain_device *dev, int phy_id)
1943 {
1944 	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
1945 	struct domain_device *child;
1946 	bool found = false;
1947 	int res, i;
1948 
1949 	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
1950 		    SAS_ADDR(dev->sas_addr), phy_id);
1951 	res = sas_ex_phy_discover(dev, phy_id);
1952 	if (res)
1953 		goto out;
1954 	/* to support the wide port inserted */
1955 	for (i = 0; i < dev->ex_dev.num_phys; i++) {
1956 		struct ex_phy *ex_phy_temp = &dev->ex_dev.ex_phy[i];
1957 		if (i == phy_id)
1958 			continue;
1959 		if (SAS_ADDR(ex_phy_temp->attached_sas_addr) ==
1960 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1961 			found = true;
1962 			break;
1963 		}
1964 	}
1965 	if (found) {
1966 		sas_ex_join_wide_port(dev, phy_id);
1967 		return 0;
1968 	}
1969 	res = sas_ex_discover_devices(dev, phy_id);
1970 	if (!res)
1971 		goto out;
1972 	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
1973 		if (SAS_ADDR(child->sas_addr) ==
1974 		    SAS_ADDR(ex_phy->attached_sas_addr)) {
1975 			if (child->dev_type == EDGE_DEV ||
1976 			    child->dev_type == FANOUT_DEV)
1977 				res = sas_discover_bfs_by_root(child);
1978 			break;
1979 		}
1980 	}
1981 out:
1982 	return res;
1983 }
1984 
1985 static bool dev_type_flutter(enum sas_dev_type new, enum sas_dev_type old)
1986 {
1987 	if (old == new)
1988 		return true;
1989 
1990 	/* treat device directed resets as flutter, if we went
1991 	 * SAS_END_DEV to SATA_PENDING the link needs recovery
1992 	 */
1993 	if ((old == SATA_PENDING && new == SAS_END_DEV) ||
1994 	    (old == SAS_END_DEV && new == SATA_PENDING))
1995 		return true;
1996 
1997 	return false;
1998 }
1999 
2000 static int sas_rediscover_dev(struct domain_device *dev, int phy_id, bool last)
2001 {
2002 	struct expander_device *ex = &dev->ex_dev;
2003 	struct ex_phy *phy = &ex->ex_phy[phy_id];
2004 	enum sas_dev_type type = NO_DEVICE;
2005 	u8 sas_addr[8];
2006 	int res;
2007 
2008 	res = sas_get_phy_attached_dev(dev, phy_id, sas_addr, &type);
2009 	switch (res) {
2010 	case SMP_RESP_NO_PHY:
2011 		phy->phy_state = PHY_NOT_PRESENT;
2012 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2013 		return res;
2014 	case SMP_RESP_PHY_VACANT:
2015 		phy->phy_state = PHY_VACANT;
2016 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2017 		return res;
2018 	case SMP_RESP_FUNC_ACC:
2019 		break;
2020 	}
2021 
2022 	if (SAS_ADDR(sas_addr) == 0) {
2023 		phy->phy_state = PHY_EMPTY;
2024 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2025 		return res;
2026 	} else if (SAS_ADDR(sas_addr) == SAS_ADDR(phy->attached_sas_addr) &&
2027 		   dev_type_flutter(type, phy->attached_dev_type)) {
2028 		struct domain_device *ata_dev = sas_ex_to_ata(dev, phy_id);
2029 		char *action = "";
2030 
2031 		sas_ex_phy_discover(dev, phy_id);
2032 
2033 		if (ata_dev && phy->attached_dev_type == SATA_PENDING)
2034 			action = ", needs recovery";
2035 		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter%s\n",
2036 			    SAS_ADDR(dev->sas_addr), phy_id, action);
2037 		return res;
2038 	}
2039 
2040 	/* delete the old link */
2041 	if (SAS_ADDR(phy->attached_sas_addr) &&
2042 	    SAS_ADDR(sas_addr) != SAS_ADDR(phy->attached_sas_addr)) {
2043 		SAS_DPRINTK("ex %016llx phy 0x%x replace %016llx\n",
2044 			    SAS_ADDR(dev->sas_addr), phy_id,
2045 			    SAS_ADDR(phy->attached_sas_addr));
2046 		sas_unregister_devs_sas_addr(dev, phy_id, last);
2047 	}
2048 
2049 	return sas_discover_new(dev, phy_id);
2050 }
2051 
2052 /**
2053  * sas_rediscover - revalidate the domain.
2054  * @dev:domain device to be detect.
2055  * @phy_id: the phy id will be detected.
2056  *
2057  * NOTE: this process _must_ quit (return) as soon as any connection
2058  * errors are encountered.  Connection recovery is done elsewhere.
2059  * Discover process only interrogates devices in order to discover the
2060  * domain.For plugging out, we un-register the device only when it is
2061  * the last phy in the port, for other phys in this port, we just delete it
2062  * from the port.For inserting, we do discovery when it is the
2063  * first phy,for other phys in this port, we add it to the port to
2064  * forming the wide-port.
2065  */
2066 static int sas_rediscover(struct domain_device *dev, const int phy_id)
2067 {
2068 	struct expander_device *ex = &dev->ex_dev;
2069 	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
2070 	int res = 0;
2071 	int i;
2072 	bool last = true;	/* is this the last phy of the port */
2073 
2074 	SAS_DPRINTK("ex %016llx phy%d originated BROADCAST(CHANGE)\n",
2075 		    SAS_ADDR(dev->sas_addr), phy_id);
2076 
2077 	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
2078 		for (i = 0; i < ex->num_phys; i++) {
2079 			struct ex_phy *phy = &ex->ex_phy[i];
2080 
2081 			if (i == phy_id)
2082 				continue;
2083 			if (SAS_ADDR(phy->attached_sas_addr) ==
2084 			    SAS_ADDR(changed_phy->attached_sas_addr)) {
2085 				SAS_DPRINTK("phy%d part of wide port with "
2086 					    "phy%d\n", phy_id, i);
2087 				last = false;
2088 				break;
2089 			}
2090 		}
2091 		res = sas_rediscover_dev(dev, phy_id, last);
2092 	} else
2093 		res = sas_discover_new(dev, phy_id);
2094 	return res;
2095 }
2096 
2097 /**
2098  * sas_revalidate_domain -- revalidate the domain
2099  * @port: port to the domain of interest
2100  *
2101  * NOTE: this process _must_ quit (return) as soon as any connection
2102  * errors are encountered.  Connection recovery is done elsewhere.
2103  * Discover process only interrogates devices in order to discover the
2104  * domain.
2105  */
2106 int sas_ex_revalidate_domain(struct domain_device *port_dev)
2107 {
2108 	int res;
2109 	struct domain_device *dev = NULL;
2110 
2111 	res = sas_find_bcast_dev(port_dev, &dev);
2112 	if (res)
2113 		goto out;
2114 	if (dev) {
2115 		struct expander_device *ex = &dev->ex_dev;
2116 		int i = 0, phy_id;
2117 
2118 		do {
2119 			phy_id = -1;
2120 			res = sas_find_bcast_phy(dev, &phy_id, i, true);
2121 			if (phy_id == -1)
2122 				break;
2123 			res = sas_rediscover(dev, phy_id);
2124 			i = phy_id + 1;
2125 		} while (i < ex->num_phys);
2126 	}
2127 out:
2128 	return res;
2129 }
2130 
2131 int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
2132 		    struct request *req)
2133 {
2134 	struct domain_device *dev;
2135 	int ret, type;
2136 	struct request *rsp = req->next_rq;
2137 
2138 	if (!rsp) {
2139 		printk("%s: space for a smp response is missing\n",
2140 		       __func__);
2141 		return -EINVAL;
2142 	}
2143 
2144 	/* no rphy means no smp target support (ie aic94xx host) */
2145 	if (!rphy)
2146 		return sas_smp_host_handler(shost, req, rsp);
2147 
2148 	type = rphy->identify.device_type;
2149 
2150 	if (type != SAS_EDGE_EXPANDER_DEVICE &&
2151 	    type != SAS_FANOUT_EXPANDER_DEVICE) {
2152 		printk("%s: can we send a smp request to a device?\n",
2153 		       __func__);
2154 		return -EINVAL;
2155 	}
2156 
2157 	dev = sas_find_dev_by_rphy(rphy);
2158 	if (!dev) {
2159 		printk("%s: fail to find a domain_device?\n", __func__);
2160 		return -EINVAL;
2161 	}
2162 
2163 	/* do we need to support multiple segments? */
2164 	if (req->bio->bi_vcnt > 1 || rsp->bio->bi_vcnt > 1) {
2165 		printk("%s: multiple segments req %u %u, rsp %u %u\n",
2166 		       __func__, req->bio->bi_vcnt, blk_rq_bytes(req),
2167 		       rsp->bio->bi_vcnt, blk_rq_bytes(rsp));
2168 		return -EINVAL;
2169 	}
2170 
2171 	ret = smp_execute_task(dev, bio_data(req->bio), blk_rq_bytes(req),
2172 			       bio_data(rsp->bio), blk_rq_bytes(rsp));
2173 	if (ret > 0) {
2174 		/* positive number is the untransferred residual */
2175 		rsp->resid_len = ret;
2176 		req->resid_len = 0;
2177 		ret = 0;
2178 	} else if (ret == 0) {
2179 		rsp->resid_len = 0;
2180 		req->resid_len = 0;
2181 	}
2182 
2183 	return ret;
2184 }
2185