aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/scsi/scsi_transport_sas.c
blob: fed39abeff8667adccc59550908ea0d8758d816b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
/*
 * Copyright (C) 2005-2006 Dell Inc.
 *	Released under GPL v2.
 *
 * Serial Attached SCSI (SAS) transport class.
 *
 * The SAS transport class contains common code to deal with SAS HBAs,
 * an aproximated representation of SAS topologies in the driver model,
 * and various sysfs attributes to expose these topologies and managment
 * interfaces to userspace.
 *
 * In addition to the basic SCSI core objects this transport class
 * introduces two additional intermediate objects:  The SAS PHY
 * as represented by struct sas_phy defines an "outgoing" PHY on
 * a SAS HBA or Expander, and the SAS remote PHY represented by
 * struct sas_rphy defines an "incoming" PHY on a SAS Expander or
 * end device.  Note that this is purely a software concept, the
 * underlying hardware for a PHY and a remote PHY is the exactly
 * the same.
 *
 * There is no concept of a SAS port in this code, users can see
 * what PHYs form a wide port based on the port_identifier attribute,
 * which is the same for all PHYs in a port.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>


#define SAS_HOST_ATTRS		0
#define SAS_PORT_ATTRS		17
#define SAS_RPORT_ATTRS		7

struct sas_internal {
	struct scsi_transport_template t;
	struct sas_function_template *f;

	struct class_device_attribute private_host_attrs[SAS_HOST_ATTRS];
	struct class_device_attribute private_phy_attrs[SAS_PORT_ATTRS];
	struct class_device_attribute private_rphy_attrs[SAS_RPORT_ATTRS];

	struct transport_container phy_attr_cont;
	struct transport_container rphy_attr_cont;

	/*
	 * The array of null terminated pointers to attributes
	 * needed by scsi_sysfs.c
	 */
	struct class_device_attribute *host_attrs[SAS_HOST_ATTRS + 1];
	struct class_device_attribute *phy_attrs[SAS_PORT_ATTRS + 1];
	struct class_device_attribute *rphy_attrs[SAS_RPORT_ATTRS + 1];
};
#define to_sas_internal(tmpl)	container_of(tmpl, struct sas_internal, t)

struct sas_host_attrs {
	struct list_head rphy_list;
	struct mutex lock;
	u32 next_target_id;
};
#define to_sas_host_attrs(host)	((struct sas_host_attrs *)(host)->shost_data)


/*
 * Hack to allow attributes of the same name in different objects.
 */
#define SAS_CLASS_DEVICE_ATTR(_prefix,_name,_mode,_show,_store) \
	struct class_device_attribute class_device_attr_##_prefix##_##_name = \
	__ATTR(_name,_mode,_show,_store)


/*
 * Pretty printing helpers
 */

#define sas_bitfield_name_match(title, table)			\
static ssize_t							\
get_sas_##title##_names(u32 table_key, char *buf)		\
{								\
	char *prefix = "";					\
	ssize_t len = 0;					\
	int i;							\
								\
	for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) {	\
		if (table[i].value & table_key) {		\
			len += sprintf(buf + len, "%s%s",	\
				prefix, table[i].name);		\
			prefix = ", ";				\
		}						\
	}							\
	len += sprintf(buf + len, "\n");			\
	return len;						\
}

#define sas_bitfield_name_search(title, table)			\
static ssize_t							\
get_sas_##title##_names(u32 table_key, char *buf)		\
{								\
	ssize_t len = 0;					\
	int i;							\
								\
	for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) {	\
		if (table[i].value == table_key) {		\
			len += sprintf(buf + len, "%s",		\
				table[i].name);			\
			break;					\
		}						\
	}							\
	len += sprintf(buf + len, "\n");			\
	return len;						\
}

static struct {
	u32		value;
	char		*name;
} sas_device_type_names[] = {
	{ SAS_PHY_UNUSED,		"unused" },
	{ SAS_END_DEVICE,		"end device" },
	{ SAS_EDGE_EXPANDER_DEVICE,	"edge expander" },
	{ SAS_FANOUT_EXPANDER_DEVICE,	"fanout expander" },
};
sas_bitfield_name_search(device_type, sas_device_type_names)


static struct {
	u32		value;
	char		*name;
} sas_protocol_names[] = {
	{ SAS_PROTOCOL_SATA,		"sata" },
	{ SAS_PROTOCOL_SMP,		"smp" },
	{ SAS_PROTOCOL_STP,		"stp" },
	{ SAS_PROTOCOL_SSP,		"ssp" },
};
sas_bitfield_name_match(protocol, sas_protocol_names)

static struct {
	u32		value;
	char		*name;
} sas_linkspeed_names[] = {
	{ SAS_LINK_RATE_UNKNOWN,	"Unknown" },
	{ SAS_PHY_DISABLED,		"Phy disabled" },
	{ SAS_LINK_RATE_FAILED,		"Link Rate failed" },
	{ SAS_SATA_SPINUP_HOLD,		"Spin-up hold" },
	{ SAS_LINK_RATE_1_5_GBPS,	"1.5 Gbit" },
	{ SAS_LINK_RATE_3_0_GBPS,	"3.0 Gbit" },
	{ SAS_LINK_RATE_6_0_GBPS,	"6.0 Gbit" },
};
sas_bitfield_name_search(linkspeed, sas_linkspeed_names)


/*
 * SAS host attributes
 */

static int sas_host_setup(struct transport_container *tc, struct device *dev,
			  struct class_device *cdev)
{
	struct Scsi_Host *shost = dev_to_shost(dev);
	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

	INIT_LIST_HEAD(&sas_host->rphy_list);
	mutex_init(&sas_host->lock);
	sas_host->next_target_id = 0;
	return 0;
}

static DECLARE_TRANSPORT_CLASS(sas_host_class,
		"sas_host", sas_host_setup, NULL, NULL);

static int sas_host_match(struct attribute_container *cont,
			    struct device *dev)
{
	struct Scsi_Host *shost;
	struct sas_internal *i;

	if (!scsi_is_host_device(dev))
		return 0;
	shost = dev_to_shost(dev);

	if (!shost->transportt)
		return 0;
	if (shost->transportt->host_attrs.ac.class !=
			&sas_host_class.class)
		return 0;

	i = to_sas_internal(shost->transportt);
	return &i->t.host_attrs.ac == cont;
}

static int do_sas_phy_delete(struct device *dev, void *data)
{
	if (scsi_is_sas_phy(dev))
		sas_phy_delete(dev_to_phy(dev));
	return 0;
}

/**
 * sas_remove_host  --  tear down a Scsi_Host's SAS data structures
 * @shost:	Scsi Host that is torn down
 *
 * Removes all SAS PHYs and remote PHYs for a given Scsi_Host.
 * Must be called just before scsi_remove_host for SAS HBAs.
 */
void sas_remove_host(struct Scsi_Host *shost)
{
	device_for_each_child(&shost->shost_gendev, NULL, do_sas_phy_delete);
}
EXPORT_SYMBOL(sas_remove_host);


/*
 * SAS Port attributes
 */

#define sas_phy_show_simple(field, name, format_string, cast)		\
static ssize_t								\
show_sas_phy_##name(struct class_device *cdev, char *buf)		\
{									\
	struct sas_phy *phy = transport_class_to_phy(cdev);		\
									\
	return snprintf(buf, 20, format_string, cast phy->field);	\
}

#define sas_phy_simple_attr(field, name, format_string, type)		\
	sas_phy_show_simple(field, name, format_string, (type))	\
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_sas_phy_##name, NULL)

#define sas_phy_show_protocol(field, name)				\
static ssize_t								\
show_sas_phy_##name(struct class_device *cdev, char *buf)		\
{									\
	struct sas_phy *phy = transport_class_to_phy(cdev);		\
									\
	if (!phy->field)						\
		return snprintf(buf, 20, "none\n");			\
	return get_sas_protocol_names(phy->field, buf);		\
}

#define sas_phy_protocol_attr(field, name)				\
	sas_phy_show_protocol(field, name)				\
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_sas_phy_##name, NULL)

#define sas_phy_show_linkspeed(field)					\
static ssize_t								\
show_sas_phy_##field(struct class_device *cdev, char *buf)		\
{									\
	struct sas_phy *phy = transport_class_to_phy(cdev);		\
									\
	return get_sas_linkspeed_names(phy->field, buf);		\
}

#define sas_phy_linkspeed_attr(field)					\
	sas_phy_show_linkspeed(field)					\
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_sas_phy_##field, NULL)

#define sas_phy_show_linkerror(field)					\
static ssize_t								\
show_sas_phy_##field(struct class_device *cdev, char *buf)		\
{									\
	struct sas_phy *phy = transport_class_to_phy(cdev);		\
	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);	\
	struct sas_internal *i = to_sas_internal(shost->transportt);	\
	int error;							\
									\
	if (!phy->local_attached)					\
		return -EINVAL;						\
									\
	error = i->f->get_linkerrors(phy);				\
	if (error)							\
		return error;						\
	return snprintf(buf, 20, "%u\n", phy->field);			\
}

#define sas_phy_linkerror_attr(field)					\
	sas_phy_show_linkerror(field)					\
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_sas_phy_##field, NULL)


static ssize_t
show_sas_device_type(struct class_device *cdev, char *buf)
{
	struct sas_phy *phy = transport_class_to_phy(cdev);

	if (!phy->identify.device_type)
		return snprintf(buf, 20, "none\n");
	return get_sas_device_type_names(phy->identify.device_type, buf);
}
static CLASS_DEVICE_ATTR(device_type, S_IRUGO, show_sas_device_type, NULL);

static ssize_t do_sas_phy_reset(struct class_device *cdev,
		size_t count, int hard_reset)
{
	struct sas_phy *phy = transport_class_to_phy(cdev);
	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
	struct sas_internal *i = to_sas_internal(shost->transportt);
	int error;

	if (!phy->local_attached)
		return -EINVAL;

	error = i->f->phy_reset(phy, hard_reset);
	if (error)
		return error;
	return count;
};

static ssize_t store_sas_link_reset(struct class_device *cdev,
		const char *buf, size_t count)
{
	return do_sas_phy_reset(cdev, count, 0);
}
static CLASS_DEVICE_ATTR(link_reset, S_IWUSR, NULL, store_sas_link_reset);

static ssize_t store_sas_hard_reset(struct class_device *cdev,
		const char *buf, size_t count)
{
	return do_sas_phy_reset(cdev, count, 1);
}
static CLASS_DEVICE_ATTR(hard_reset, S_IWUSR, NULL, store_sas_hard_reset);

sas_phy_protocol_attr(identify.initiator_port_protocols,
		initiator_port_protocols);
sas_phy_protocol_attr(identify.target_port_protocols,
		target_port_protocols);
sas_phy_simple_attr(identify.sas_address, sas_address, "0x%016llx\n",
		unsigned long long);
sas_phy_simple_attr(identify.phy_identifier, phy_identifier, "%d\n", u8);
sas_phy_simple_attr(port_identifier, port_identifier, "%d\n", u8);
sas_phy_linkspeed_attr(negotiated_linkrate);
sas_phy_linkspeed_attr(minimum_linkrate_hw);
sas_phy_linkspeed_attr(minimum_linkrate);
sas_phy_linkspeed_attr(maximum_linkrate_hw);
sas_phy_linkspeed_attr(maximum_linkrate);
sas_phy_linkerror_attr(invalid_dword_count);
sas_phy_linkerror_attr(running_disparity_error_count);
sas_phy_linkerror_attr(loss_of_dword_sync_count);
sas_phy_linkerror_attr(phy_reset_problem_count);


static DECLARE_TRANSPORT_CLASS(sas_phy_class,
		"sas_phy", NULL, NULL, NULL);

static int sas_phy_match(struct attribute_container *cont, struct device *dev)
{
	struct Scsi_Host *shost;
	struct sas_internal *i;

	if (!scsi_is_sas_phy(dev))
		return 0;
	shost = dev_to_shost(dev->parent);

	if (!shost->transportt)
		return 0;
	if (shost->transportt->host_attrs.ac.class !=
			&sas_host_class.class)
		return 0;

	i = to_sas_internal(shost->transportt);
	return &i->phy_attr_cont.ac == cont;
}

static void sas_phy_release(struct device *dev)
{
	struct sas_phy *phy = dev_to_phy(dev);

	put_device(dev->parent);
	kfree(phy);
}

/**
 * sas_phy_alloc  --  allocates and initialize a SAS PHY structure
 * @parent:	Parent device
 * @number:	Phy index
 *
 * Allocates an SAS PHY structure.  It will be added in the device tree
 * below the device specified by @parent, which has to be either a Scsi_Host
 * or sas_rphy.
 *
 * Returns:
 *	SAS PHY allocated or %NULL if the allocation failed.
 */
struct sas_phy *sas_phy_alloc(struct device *parent, int number)
{
	struct Scsi_Host *shost = dev_to_shost(parent);
	struct sas_phy *phy;

	phy = kzalloc(sizeof(*phy), GFP_KERNEL);
	if (!phy)
		return NULL;

	get_device(parent);

	phy->number = number;

	device_initialize(&phy->dev);
	phy->dev.parent = get_device(parent);
	phy->dev.release = sas_phy_release;
	sprintf(phy->dev.bus_id, "phy-%d:%d", shost->host_no, number);

	transport_setup_device(&phy->dev);

	return phy;
}
EXPORT_SYMBOL(sas_phy_alloc);

/**
 * sas_phy_add  --  add a SAS PHY to the device hierachy
 * @phy:	The PHY to be added
 *
 * Publishes a SAS PHY to the rest of the system.
 */
int sas_phy_add(struct sas_phy *phy)
{
	int error;

	error = device_add(&phy->dev);
	if (!error) {
		transport_add_device(&phy->dev);
		transport_configure_device(&phy->dev);
	}

	return error;
}
EXPORT_SYMBOL(sas_phy_add);

/**
 * sas_phy_free  --  free a SAS PHY
 * @phy:	SAS PHY to free
 *
 * Frees the specified SAS PHY.
 *
 * Note:
 *   This function must only be called on a PHY that has not
 *   sucessfully been added using sas_phy_add().
 */
void sas_phy_free(struct sas_phy *phy)
{
	transport_destroy_device(&phy->dev);
	put_device(phy->dev.parent);
	put_device(phy->dev.parent);
	put_device(phy->dev.parent);
	kfree(phy);
}
EXPORT_SYMBOL(sas_phy_free);

/**
 * sas_phy_delete  --  remove SAS PHY
 * @phy:	SAS PHY to remove
 *
 * Removes the specified SAS PHY.  If the SAS PHY has an
 * associated remote PHY it is removed before.
 */
void
sas_phy_delete(struct sas_phy *phy)
{
	struct device *dev = &phy->dev;

	if (phy->rphy)
		sas_rphy_delete(phy->rphy);

	transport_remove_device(dev);
	device_del(dev);
	transport_destroy_device(dev);
	put_device(dev->parent);
}
EXPORT_SYMBOL(sas_phy_delete);

/**
 * scsi_is_sas_phy  --  check if a struct device represents a SAS PHY
 * @dev:	device to check
 *
 * Returns:
 *	%1 if the device represents a SAS PHY, %0 else
 */
int scsi_is_sas_phy(const struct device *dev)
{
	return dev->release == sas_phy_release;
}
EXPORT_SYMBOL(scsi_is_sas_phy);

/*
 * SAS remote PHY attributes.
 */

#define sas_rphy_show_simple(field, name, format_string, cast)		\
static ssize_t								\
show_sas_rphy_##name(struct class_device *cdev, char *buf)		\
{									\
	struct sas_rphy *rphy = transport_class_to_rphy(cdev);	\
									\
	return snprintf(buf, 20, format_string, cast rphy->field);	\
}

#define sas_rphy_simple_attr(field, name, format_string, type)		\
	sas_rphy_show_simple(field, name, format_string, (type))	\
static SAS_CLASS_DEVICE_ATTR(rphy, name, S_IRUGO, 			\
		show_sas_rphy_##name, NULL)

#define sas_rphy_show_protocol(field, name)				\
static ssize_t								\
show_sas_rphy_##name(struct class_device *cdev, char *buf)		\
{									\
	struct sas_rphy *rphy = transport_class_to_rphy(cdev);	\
									\
	if (!rphy->field)					\
		return snprintf(buf, 20, "none\n");			\
	return get_sas_protocol_names(rphy->field, buf);	\
}

#define sas_rphy_protocol_attr(field, name)				\
	sas_rphy_show_protocol(field, name)				\
static SAS_CLASS_DEVICE_ATTR(rphy, name, S_IRUGO,			\
		show_sas_rphy_##name, NULL)

static ssize_t
show_sas_rphy_device_type(struct class_device *cdev, char *buf)
{
	struct sas_rphy *rphy = transport_class_to_rphy(cdev);

	if (!rphy->identify.device_type)
		return snprintf(buf, 20, "none\n");
	return get_sas_device_type_names(
			rphy->identify.device_type, buf);
}

static SAS_CLASS_DEVICE_ATTR(rphy, device_type, S_IRUGO,
		show_sas_rphy_device_type, NULL);

static ssize_t
show_sas_rphy_enclosure_identifier(struct class_device *cdev, char *buf)
{
	struct sas_rphy *rphy = transport_class_to_rphy(cdev);
	struct sas_phy *phy = dev_to_phy(rphy->dev.parent);
	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
	struct sas_internal *i = to_sas_internal(shost->transportt);
	u64 identifier;
	int error;

	/*
	 * Only devices behind an expander are supported, because the
	 * enclosure identifier is a SMP feature.
	 */
	if (phy->local_attached)
		return -EINVAL;

	error = i->f->get_enclosure_identifier(rphy, &identifier);
	if (error)
		return error;
	return sprintf(buf, "0x%llx\n", (unsigned long long)identifier);
}

static SAS_CLASS_DEVICE_ATTR(rphy, enclosure_identifier, S_IRUGO,
		show_sas_rphy_enclosure_identifier, NULL);

static ssize_t
show_sas_rphy_bay_identifier(struct class_device *cdev, char *buf)
{
	struct sas_rphy *rphy = transport_class_to_rphy(cdev);
	struct sas_phy *phy = dev_to_phy(rphy->dev.parent);
	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
	struct sas_internal *i = to_sas_internal(shost->transportt);
	int val;

	if (phy->local_attached)
		return -EINVAL;

	val = i->f->get_bay_identifier(rphy);
	if (val < 0)
		return val;
	return sprintf(buf, "%d\n", val);
}

static SAS_CLASS_DEVICE_ATTR(rphy, bay_identifier, S_IRUGO,
		show_sas_rphy_bay_identifier, NULL);

sas_rphy_protocol_attr(identify.initiator_port_protocols,
		initiator_port_protocols);
sas_rphy_protocol_attr(identify.target_port_protocols, target_port_protocols);
sas_rphy_simple_attr(identify.sas_address, sas_address, "0x%016llx\n",
		unsigned long long);
sas_rphy_simple_attr(identify.phy_identifier, phy_identifier, "%d\n", u8);

static DECLARE_TRANSPORT_CLASS(sas_rphy_class,
		"sas_rphy", NULL, NULL, NULL);

static int sas_rphy_match(struct attribute_container *cont, struct device *dev)
{
	struct Scsi_Host *shost;
	struct sas_internal *i;

	if (!scsi_is_sas_rphy(dev))
		return 0;
	shost = dev_to_shost(dev->parent->parent);

	if (!shost->transportt)
		return 0;
	if (shost->transportt->host_attrs.ac.class !=
			&sas_host_class.class)
		return 0;

	i = to_sas_internal(shost->transportt);
	return &i->rphy_attr_cont.ac == cont;
}

static void sas_rphy_release(struct device *dev)
{
	struct sas_rphy *rphy = dev_to_rphy(dev);

	put_device(dev->parent);
	kfree(rphy);
}

/**
 * sas_rphy_alloc  --  allocates and initialize a SAS remote PHY structure
 * @parent:		SAS PHY this remote PHY is conneted to
 *
 * Allocates an SAS remote PHY structure, connected to @parent.
 *
 * Returns:
 *	SAS PHY allocated or %NULL if the allocation failed.
 */
struct sas_rphy *sas_rphy_alloc(struct sas_phy *parent)
{
	struct Scsi_Host *shost = dev_to_shost(&parent->dev);
	struct sas_rphy *rphy;

	rphy = kzalloc(sizeof(*rphy), GFP_KERNEL);
	if (!rphy) {
		put_device(&parent->dev);
		return NULL;
	}

	device_initialize(&rphy->dev);
	rphy->dev.parent = get_device(&parent->dev);
	rphy->dev.release = sas_rphy_release;
	sprintf(rphy->dev.bus_id, "rphy-%d:%d-%d",
		shost->host_no, parent->port_identifier, parent->number);
	transport_setup_device(&rphy->dev);

	return rphy;
}
EXPORT_SYMBOL(sas_rphy_alloc);

/**
 * sas_rphy_add  --  add a SAS remote PHY to the device hierachy
 * @rphy:	The remote PHY to be added
 *
 * Publishes a SAS remote PHY to the rest of the system.
 */
int sas_rphy_add(struct sas_rphy *rphy)
{
	struct sas_phy *parent = dev_to_phy(rphy->dev.parent);
	struct Scsi_Host *shost = dev_to_shost(parent->dev.parent);
	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
	struct sas_identify *identify = &rphy->identify;
	int error;

	if (parent->rphy)
		return -ENXIO;
	parent->rphy = rphy;

	error = device_add(&rphy->dev);
	if (error)
		return error;
	transport_add_device(&rphy->dev);
	transport_configure_device(&rphy->dev);

	mutex_lock(&sas_host->lock);
	list_add_tail(&rphy->list, &sas_host->rphy_list);
	if (identify->device_type == SAS_END_DEVICE &&
	    (identify->target_port_protocols &
	     (SAS_PROTOCOL_SSP|SAS_PROTOCOL_STP|SAS_PROTOCOL_SATA)))
		rphy->scsi_target_id = sas_host->next_target_id++;
	else
		rphy->scsi_target_id = -1;
	mutex_unlock(&sas_host->lock);

	if (rphy->scsi_target_id != -1) {
		scsi_scan_target(&rphy->dev, parent->port_identifier,
				rphy->scsi_target_id, ~0, 0);
	}

	return 0;
}
EXPORT_SYMBOL(sas_rphy_add);

/**
 * sas_rphy_free  --  free a SAS remote PHY
 * @rphy	SAS remote PHY to free
 *
 * Frees the specified SAS remote PHY.
 *
 * Note:
 *   This function must only be called on a remote
 *   PHY that has not sucessfully been added using
 *   sas_rphy_add().
 */
void sas_rphy_free(struct sas_rphy *rphy)
{
	struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent->parent);
	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

	mutex_lock(&sas_host->lock);
	list_del(&rphy->list);
	mutex_unlock(&sas_host->lock);

	transport_destroy_device(&rphy->dev);
	put_device(rphy->dev.parent);
	put_device(rphy->dev.parent);
	put_device(rphy->dev.parent);
	kfree(rphy);
}
EXPORT_SYMBOL(sas_rphy_free);

/**
 * sas_rphy_delete  --  remove SAS remote PHY
 * @rphy:	SAS remote PHY to remove
 *
 * Removes the specified SAS remote PHY.
 */
void
sas_rphy_delete(struct sas_rphy *rphy)
{
	struct device *dev = &rphy->dev;
	struct sas_phy *parent = dev_to_phy(dev->parent);
	struct Scsi_Host *shost = dev_to_shost(parent->dev.parent);
	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

	switch (rphy->identify.device_type) {
	case SAS_END_DEVICE:
		scsi_remove_target(dev);
		break;
	case SAS_EDGE_EXPANDER_DEVICE:
	case SAS_FANOUT_EXPANDER_DEVICE:
		device_for_each_child(dev, NULL, do_sas_phy_delete);
		break;
	default:
		break;
	}

	transport_remove_device(dev);
	device_del(dev);
	transport_destroy_device(dev);

	mutex_lock(&sas_host->lock);
	list_del(&rphy->list);
	mutex_unlock(&sas_host->lock);

	parent->rphy = NULL;

	put_device(&parent->dev);
}
EXPORT_SYMBOL(sas_rphy_delete);

/**
 * scsi_is_sas_rphy  --  check if a struct device represents a SAS remote PHY
 * @dev:	device to check
 *
 * Returns:
 *	%1 if the device represents a SAS remote PHY, %0 else
 */
int scsi_is_sas_rphy(const struct device *dev)
{
	return dev->release == sas_rphy_release;
}
EXPORT_SYMBOL(scsi_is_sas_rphy);


/*
 * SCSI scan helper
 */

static int sas_user_scan(struct Scsi_Host *shost, uint channel,
		uint id, uint lun)
{
	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
	struct sas_rphy *rphy;

	mutex_lock(&sas_host->lock);
	list_for_each_entry(rphy, &sas_host->rphy_list, list) {
		struct sas_phy *parent = dev_to_phy(rphy->dev.parent);

		if (rphy->scsi_target_id == -1)
			continue;

		if ((channel == SCAN_WILD_CARD || channel == parent->port_identifier) &&
		    (id == SCAN_WILD_CARD || id == rphy->scsi_target_id)) {
			scsi_scan_target(&rphy->dev, parent->port_identifier,
					 rphy->scsi_target_id, lun, 1);
		}
	}
	mutex_unlock(&sas_host->lock);

	return 0;
}


/*
 * Setup / Teardown code
 */

#define SETUP_RPORT_ATTRIBUTE(field)					\
	i->private_rphy_attrs[count] = class_device_attr_##field;	\
	i->private_rphy_attrs[count].attr.mode = S_IRUGO;		\
	i->private_rphy_attrs[count].store = NULL;			\
	i->rphy_attrs[count] = &i->private_rphy_attrs[count];	\
	count++

#define SETUP_PORT_ATTRIBUTE(field)					\
	i->private_phy_attrs[count] = class_device_attr_##field;	\
        i->private_phy_attrs[count].attr.mode = S_IRUGO;		\
        i->private_phy_attrs[count].store = NULL;			\
        i->phy_attrs[count] = &i->private_phy_attrs[count];		\
	count++

#define SETUP_PORT_ATTRIBUTE_WRONLY(field)				\
	i->private_phy_attrs[count] = class_device_attr_##field;	\
	i->private_phy_attrs[count].attr.mode = S_IWUGO;		\
	i->private_phy_attrs[count].show = NULL;			\
	i->phy_attrs[count] = &i->private_phy_attrs[count];		\
	count++


/**
 * sas_attach_transport  --  instantiate SAS transport template
 * @ft:		SAS transport class function template
 */
struct scsi_transport_template *
sas_attach_transport(struct sas_function_template *ft)
{
	struct sas_internal *i;
	int count;

	i = kzalloc(sizeof(struct sas_internal), GFP_KERNEL);
	if (!i)
		return NULL;

	i->t.user_scan = sas_user_scan;

	i->t.host_attrs.ac.attrs = &i->host_attrs[0];
	i->t.host_attrs.ac.class = &sas_host_class.class;
	i->t.host_attrs.ac.match = sas_host_match;
	transport_container_register(&i->t.host_attrs);
	i->t.host_size = sizeof(struct sas_host_attrs);

	i->phy_attr_cont.ac.class = &sas_phy_class.class;
	i->phy_attr_cont.ac.attrs = &i->phy_attrs[0];
	i->phy_attr_cont.ac.match = sas_phy_match;
	transport_container_register(&i->phy_attr_cont);

	i->rphy_attr_cont.ac.class = &sas_rphy_class.class;
	i->rphy_attr_cont.ac.attrs = &i->rphy_attrs[0];
	i->rphy_attr_cont.ac.match = sas_rphy_match;
	transport_container_register(&i->rphy_attr_cont);

	i->f = ft;

	count = 0;
	i->host_attrs[count] = NULL;

	count = 0;
	SETUP_PORT_ATTRIBUTE(initiator_port_protocols);
	SETUP_PORT_ATTRIBUTE(target_port_protocols);
	SETUP_PORT_ATTRIBUTE(device_type);
	SETUP_PORT_ATTRIBUTE(sas_address);
	SETUP_PORT_ATTRIBUTE(phy_identifier);
	SETUP_PORT_ATTRIBUTE(port_identifier);
	SETUP_PORT_ATTRIBUTE(negotiated_linkrate);
	SETUP_PORT_ATTRIBUTE(minimum_linkrate_hw);
	SETUP_PORT_ATTRIBUTE(minimum_linkrate);
	SETUP_PORT_ATTRIBUTE(maximum_linkrate_hw);
	SETUP_PORT_ATTRIBUTE(maximum_linkrate);

	SETUP_PORT_ATTRIBUTE(invalid_dword_count);
	SETUP_PORT_ATTRIBUTE(running_disparity_error_count);
	SETUP_PORT_ATTRIBUTE(loss_of_dword_sync_count);
	SETUP_PORT_ATTRIBUTE(phy_reset_problem_count);
	SETUP_PORT_ATTRIBUTE_WRONLY(link_reset);
	SETUP_PORT_ATTRIBUTE_WRONLY(hard_reset);
	i->phy_attrs[count] = NULL;

	count = 0;
	SETUP_RPORT_ATTRIBUTE(rphy_initiator_port_protocols);
	SETUP_RPORT_ATTRIBUTE(rphy_target_port_protocols);
	SETUP_RPORT_ATTRIBUTE(rphy_device_type);
	SETUP_RPORT_ATTRIBUTE(rphy_sas_address);
	SETUP_RPORT_ATTRIBUTE(rphy_phy_identifier);
	SETUP_RPORT_ATTRIBUTE(rphy_enclosure_identifier);
	SETUP_RPORT_ATTRIBUTE(rphy_bay_identifier);
	i->rphy_attrs[count] = NULL;

	return &i->t;
}
EXPORT_SYMBOL(sas_attach_transport);

/**
 * sas_release_transport  --  release SAS transport template instance
 * @t:		transport template instance
 */
void sas_release_transport(struct scsi_transport_template *t)
{
	struct sas_internal *i = to_sas_internal(t);

	transport_container_unregister(&i->t.host_attrs);
	transport_container_unregister(&i->phy_attr_cont);
	transport_container_unregister(&i->rphy_attr_cont);

	kfree(i);
}
EXPORT_SYMBOL(sas_release_transport);

static __init int sas_transport_init(void)
{
	int error;

	error = transport_class_register(&sas_host_class);
	if (error)
		goto out;
	error = transport_class_register(&sas_phy_class);
	if (error)
		goto out_unregister_transport;
	error = transport_class_register(&sas_rphy_class);
	if (error)
		goto out_unregister_phy;

	return 0;

 out_unregister_phy:
	transport_class_unregister(&sas_phy_class);
 out_unregister_transport:
	transport_class_unregister(&sas_host_class);
 out:
	return error;

}

static void __exit sas_transport_exit(void)
{
	transport_class_unregister(&sas_host_class);
	transport_class_unregister(&sas_phy_class);
	transport_class_unregister(&sas_rphy_class);
}

MODULE_AUTHOR("Christoph Hellwig");
MODULE_DESCRIPTION("SAS Transphy Attributes");
MODULE_LICENSE("GPL");

module_init(sas_transport_init);
module_exit(sas_transport_exit);