summaryrefslogtreecommitdiff
path: root/drivers/s390/scsi/zfcp_fc.c
blob: db00b5e3abbe361143c83dc5d6becfaa0e62aac0 (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
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
// SPDX-License-Identifier: GPL-2.0
/*
 * zfcp device driver
 *
 * Fibre Channel related functions for the zfcp device driver.
 *
 * Copyright IBM Corp. 2008, 2017
 */

#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/random.h>
#include <linux/bsg-lib.h>
#include <scsi/fc/fc_els.h>
#include <scsi/libfc.h>
#include "zfcp_ext.h"
#include "zfcp_fc.h"

struct kmem_cache *zfcp_fc_req_cache;

static u32 zfcp_fc_rscn_range_mask[] = {
	[ELS_ADDR_FMT_PORT]		= 0xFFFFFF,
	[ELS_ADDR_FMT_AREA]		= 0xFFFF00,
	[ELS_ADDR_FMT_DOM]		= 0xFF0000,
	[ELS_ADDR_FMT_FAB]		= 0x000000,
};

static bool no_auto_port_rescan;
module_param(no_auto_port_rescan, bool, 0600);
MODULE_PARM_DESC(no_auto_port_rescan,
		 "no automatic port_rescan (default off)");

static unsigned int port_scan_backoff = 500;
module_param(port_scan_backoff, uint, 0600);
MODULE_PARM_DESC(port_scan_backoff,
	"upper limit of port scan random backoff in msecs (default 500)");

static unsigned int port_scan_ratelimit = 60000;
module_param(port_scan_ratelimit, uint, 0600);
MODULE_PARM_DESC(port_scan_ratelimit,
	"minimum interval between port scans in msecs (default 60000)");

unsigned int zfcp_fc_port_scan_backoff(void)
{
	if (!port_scan_backoff)
		return 0;
	return get_random_int() % port_scan_backoff;
}

static void zfcp_fc_port_scan_time(struct zfcp_adapter *adapter)
{
	unsigned long interval = msecs_to_jiffies(port_scan_ratelimit);
	unsigned long backoff = msecs_to_jiffies(zfcp_fc_port_scan_backoff());

	adapter->next_port_scan = jiffies + interval + backoff;
}

static void zfcp_fc_port_scan(struct zfcp_adapter *adapter)
{
	unsigned long now = jiffies;
	unsigned long next = adapter->next_port_scan;
	unsigned long delay = 0, max;

	/* delay only needed within waiting period */
	if (time_before(now, next)) {
		delay = next - now;
		/* paranoia: never ever delay scans longer than specified */
		max = msecs_to_jiffies(port_scan_ratelimit + port_scan_backoff);
		delay = min(delay, max);
	}

	queue_delayed_work(adapter->work_queue, &adapter->scan_work, delay);
}

void zfcp_fc_conditional_port_scan(struct zfcp_adapter *adapter)
{
	if (no_auto_port_rescan)
		return;

	zfcp_fc_port_scan(adapter);
}

void zfcp_fc_inverse_conditional_port_scan(struct zfcp_adapter *adapter)
{
	if (!no_auto_port_rescan)
		return;

	zfcp_fc_port_scan(adapter);
}

/**
 * zfcp_fc_post_event - post event to userspace via fc_transport
 * @work: work struct with enqueued events
 */
void zfcp_fc_post_event(struct work_struct *work)
{
	struct zfcp_fc_event *event = NULL, *tmp = NULL;
	LIST_HEAD(tmp_lh);
	struct zfcp_fc_events *events = container_of(work,
					struct zfcp_fc_events, work);
	struct zfcp_adapter *adapter = container_of(events, struct zfcp_adapter,
						events);

	spin_lock_bh(&events->list_lock);
	list_splice_init(&events->list, &tmp_lh);
	spin_unlock_bh(&events->list_lock);

	list_for_each_entry_safe(event, tmp, &tmp_lh, list) {
		fc_host_post_event(adapter->scsi_host, fc_get_event_number(),
				   event->code, event->data);
		list_del(&event->list);
		kfree(event);
	}
}

/**
 * zfcp_fc_enqueue_event - safely enqueue FC HBA API event from irq context
 * @adapter: The adapter where to enqueue the event
 * @event_code: The event code (as defined in fc_host_event_code in
 *		scsi_transport_fc.h)
 * @event_data: The event data (e.g. n_port page in case of els)
 */
void zfcp_fc_enqueue_event(struct zfcp_adapter *adapter,
			   enum fc_host_event_code event_code, u32 event_data)
{
	struct zfcp_fc_event *event;

	event = kmalloc(sizeof(struct zfcp_fc_event), GFP_ATOMIC);
	if (!event)
		return;

	event->code = event_code;
	event->data = event_data;

	spin_lock(&adapter->events.list_lock);
	list_add_tail(&event->list, &adapter->events.list);
	spin_unlock(&adapter->events.list_lock);

	queue_work(adapter->work_queue, &adapter->events.work);
}

static int zfcp_fc_wka_port_get(struct zfcp_fc_wka_port *wka_port)
{
	if (mutex_lock_interruptible(&wka_port->mutex))
		return -ERESTARTSYS;

	if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
	    wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
		wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
		if (zfcp_fsf_open_wka_port(wka_port))
			wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
	}

	mutex_unlock(&wka_port->mutex);

	wait_event(wka_port->completion_wq,
		   wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);

	if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
		atomic_inc(&wka_port->refcount);
		return 0;
	}
	return -EIO;
}

static void zfcp_fc_wka_port_offline(struct work_struct *work)
{
	struct delayed_work *dw = to_delayed_work(work);
	struct zfcp_fc_wka_port *wka_port =
			container_of(dw, struct zfcp_fc_wka_port, work);

	mutex_lock(&wka_port->mutex);
	if ((atomic_read(&wka_port->refcount) != 0) ||
	    (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
		goto out;

	wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
	if (zfcp_fsf_close_wka_port(wka_port)) {
		wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
		wake_up(&wka_port->completion_wq);
	}
out:
	mutex_unlock(&wka_port->mutex);
}

static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
{
	if (atomic_dec_return(&wka_port->refcount) != 0)
		return;
	/* wait 10 milliseconds, other reqs might pop in */
	schedule_delayed_work(&wka_port->work, HZ / 100);
}

static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
				  struct zfcp_adapter *adapter)
{
	init_waitqueue_head(&wka_port->completion_wq);

	wka_port->adapter = adapter;
	wka_port->d_id = d_id;

	wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
	atomic_set(&wka_port->refcount, 0);
	mutex_init(&wka_port->mutex);
	INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
}

static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
{
	cancel_delayed_work_sync(&wka->work);
	mutex_lock(&wka->mutex);
	wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
	mutex_unlock(&wka->mutex);
}

void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
{
	if (!gs)
		return;
	zfcp_fc_wka_port_force_offline(&gs->ms);
	zfcp_fc_wka_port_force_offline(&gs->ts);
	zfcp_fc_wka_port_force_offline(&gs->ds);
	zfcp_fc_wka_port_force_offline(&gs->as);
}

static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
				   struct fc_els_rscn_page *page)
{
	unsigned long flags;
	struct zfcp_adapter *adapter = fsf_req->adapter;
	struct zfcp_port *port;

	read_lock_irqsave(&adapter->port_list_lock, flags);
	list_for_each_entry(port, &adapter->port_list, list) {
		if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
			zfcp_fc_test_link(port);
		if (!port->d_id)
			zfcp_erp_port_reopen(port,
					     ZFCP_STATUS_COMMON_ERP_FAILED,
					     "fcrscn1");
	}
	read_unlock_irqrestore(&adapter->port_list_lock, flags);
}

static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
{
	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
	struct fc_els_rscn *head;
	struct fc_els_rscn_page *page;
	u16 i;
	u16 no_entries;
	unsigned int afmt;

	head = (struct fc_els_rscn *) status_buffer->payload.data;
	page = (struct fc_els_rscn_page *) head;

	/* see FC-FS */
	no_entries = be16_to_cpu(head->rscn_plen) /
		sizeof(struct fc_els_rscn_page);

	for (i = 1; i < no_entries; i++) {
		/* skip head and start with 1st element */
		page++;
		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
				       page);
		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
				      *(u32 *)page);
	}
	zfcp_fc_conditional_port_scan(fsf_req->adapter);
}

static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
{
	unsigned long flags;
	struct zfcp_adapter *adapter = req->adapter;
	struct zfcp_port *port;

	read_lock_irqsave(&adapter->port_list_lock, flags);
	list_for_each_entry(port, &adapter->port_list, list)
		if (port->wwpn == wwpn) {
			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
			break;
		}
	read_unlock_irqrestore(&adapter->port_list_lock, flags);
}

static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
{
	struct fsf_status_read_buffer *status_buffer;
	struct fc_els_flogi *plogi;

	status_buffer = (struct fsf_status_read_buffer *) req->data;
	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
	zfcp_fc_incoming_wwpn(req, be64_to_cpu(plogi->fl_wwpn));
}

static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
{
	struct fsf_status_read_buffer *status_buffer =
		(struct fsf_status_read_buffer *)req->data;
	struct fc_els_logo *logo =
		(struct fc_els_logo *) status_buffer->payload.data;

	zfcp_fc_incoming_wwpn(req, be64_to_cpu(logo->fl_n_port_wwn));
}

/**
 * zfcp_fc_incoming_els - handle incoming ELS
 * @fsf_req: request which contains incoming ELS
 */
void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
{
	struct fsf_status_read_buffer *status_buffer =
		(struct fsf_status_read_buffer *) fsf_req->data;
	unsigned int els_type = status_buffer->payload.data[0];

	zfcp_dbf_san_in_els("fciels1", fsf_req);
	if (els_type == ELS_PLOGI)
		zfcp_fc_incoming_plogi(fsf_req);
	else if (els_type == ELS_LOGO)
		zfcp_fc_incoming_logo(fsf_req);
	else if (els_type == ELS_RSCN)
		zfcp_fc_incoming_rscn(fsf_req);
}

static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
{
	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;

	if (ct_els->status)
		return;
	if (gid_pn_rsp->ct_hdr.ct_cmd != cpu_to_be16(FC_FS_ACC))
		return;

	/* looks like a valid d_id */
	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
}

static void zfcp_fc_complete(void *data)
{
	complete(data);
}

static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
{
	ct_hdr->ct_rev = FC_CT_REV;
	ct_hdr->ct_fs_type = FC_FST_DIR;
	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
	ct_hdr->ct_cmd = cpu_to_be16(cmd);
	ct_hdr->ct_mr_size = cpu_to_be16(mr_size / 4);
}

static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
				     struct zfcp_fc_req *fc_req)
{
	struct zfcp_adapter *adapter = port->adapter;
	DECLARE_COMPLETION_ONSTACK(completion);
	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
	int ret;

	/* setup parameters for send generic command */
	fc_req->ct_els.port = port;
	fc_req->ct_els.handler = zfcp_fc_complete;
	fc_req->ct_els.handler_data = &completion;
	fc_req->ct_els.req = &fc_req->sg_req;
	fc_req->ct_els.resp = &fc_req->sg_rsp;
	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));

	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
	gid_pn_req->gid_pn.fn_wwpn = cpu_to_be64(port->wwpn);

	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
			       adapter->pool.gid_pn_req,
			       ZFCP_FC_CTELS_TMO);
	if (!ret) {
		wait_for_completion(&completion);
		zfcp_fc_ns_gid_pn_eval(fc_req);
	}
	return ret;
}

/**
 * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
 * @port: port where GID_PN request is needed
 * return: -ENOMEM on error, 0 otherwise
 */
static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
{
	int ret;
	struct zfcp_fc_req *fc_req;
	struct zfcp_adapter *adapter = port->adapter;

	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
	if (!fc_req)
		return -ENOMEM;

	memset(fc_req, 0, sizeof(*fc_req));

	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
	if (ret)
		goto out;

	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);

	zfcp_fc_wka_port_put(&adapter->gs->ds);
out:
	mempool_free(fc_req, adapter->pool.gid_pn);
	return ret;
}

void zfcp_fc_port_did_lookup(struct work_struct *work)
{
	int ret;
	struct zfcp_port *port = container_of(work, struct zfcp_port,
					      gid_pn_work);

	set_worker_desc("zgidpn%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
	ret = zfcp_fc_ns_gid_pn(port);
	if (ret) {
		/* could not issue gid_pn for some reason */
		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
		goto out;
	}

	if (!port->d_id) {
		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
		goto out;
	}

	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
out:
	put_device(&port->dev);
}

/**
 * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
 * @port: The zfcp_port to lookup the d_id for.
 */
void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
{
	get_device(&port->dev);
	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
		put_device(&port->dev);
}

/**
 * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
 * @port: zfcp_port structure
 * @plogi: plogi payload
 *
 * Evaluate PLOGI playload and copy important fields into zfcp_port structure
 */
void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
{
	if (be64_to_cpu(plogi->fl_wwpn) != port->wwpn) {
		port->d_id = 0;
		dev_warn(&port->adapter->ccw_device->dev,
			 "A port opened with WWPN 0x%016Lx returned data that "
			 "identifies it as WWPN 0x%016Lx\n",
			 (unsigned long long) port->wwpn,
			 (unsigned long long) be64_to_cpu(plogi->fl_wwpn));
		return;
	}

	port->wwnn = be64_to_cpu(plogi->fl_wwnn);
	port->maxframe_size = be16_to_cpu(plogi->fl_csp.sp_bb_data);

	if (plogi->fl_cssp[0].cp_class & cpu_to_be16(FC_CPC_VALID))
		port->supported_classes |= FC_COS_CLASS1;
	if (plogi->fl_cssp[1].cp_class & cpu_to_be16(FC_CPC_VALID))
		port->supported_classes |= FC_COS_CLASS2;
	if (plogi->fl_cssp[2].cp_class & cpu_to_be16(FC_CPC_VALID))
		port->supported_classes |= FC_COS_CLASS3;
	if (plogi->fl_cssp[3].cp_class & cpu_to_be16(FC_CPC_VALID))
		port->supported_classes |= FC_COS_CLASS4;
}

static void zfcp_fc_adisc_handler(void *data)
{
	struct zfcp_fc_req *fc_req = data;
	struct zfcp_port *port = fc_req->ct_els.port;
	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;

	if (fc_req->ct_els.status) {
		/* request rejected or timed out */
		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
					    "fcadh_1");
		goto out;
	}

	if (!port->wwnn)
		port->wwnn = be64_to_cpu(adisc_resp->adisc_wwnn);

	if ((port->wwpn != be64_to_cpu(adisc_resp->adisc_wwpn)) ||
	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
				     "fcadh_2");
		goto out;
	}

	/* port is good, unblock rport without going through erp */
	zfcp_scsi_schedule_rport_register(port);
 out:
	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
	put_device(&port->dev);
	kmem_cache_free(zfcp_fc_req_cache, fc_req);
}

static int zfcp_fc_adisc(struct zfcp_port *port)
{
	struct zfcp_fc_req *fc_req;
	struct zfcp_adapter *adapter = port->adapter;
	struct Scsi_Host *shost = adapter->scsi_host;
	int ret;

	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
	if (!fc_req)
		return -ENOMEM;

	fc_req->ct_els.port = port;
	fc_req->ct_els.req = &fc_req->sg_req;
	fc_req->ct_els.resp = &fc_req->sg_rsp;
	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
		    sizeof(struct fc_els_adisc));
	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
		    sizeof(struct fc_els_adisc));

	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
	fc_req->ct_els.handler_data = fc_req;

	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
	   without FC-AL-2 capability, so we don't set it */
	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));

	ret = zfcp_fsf_send_els(adapter, port->d_id, &fc_req->ct_els,
				ZFCP_FC_CTELS_TMO);
	if (ret)
		kmem_cache_free(zfcp_fc_req_cache, fc_req);

	return ret;
}

void zfcp_fc_link_test_work(struct work_struct *work)
{
	struct zfcp_port *port =
		container_of(work, struct zfcp_port, test_link_work);
	int retval;

	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
	get_device(&port->dev);
	port->rport_task = RPORT_DEL;
	zfcp_scsi_rport_work(&port->rport_work);

	/* only issue one test command at one time per port */
	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
		goto out;

	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);

	retval = zfcp_fc_adisc(port);
	if (retval == 0)
		return;

	/* send of ADISC was not possible */
	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");

out:
	put_device(&port->dev);
}

/**
 * zfcp_fc_test_link - lightweight link test procedure
 * @port: port to be tested
 *
 * Test status of a link to a remote port using the ELS command ADISC.
 * If there is a problem with the remote port, error recovery steps
 * will be triggered.
 */
void zfcp_fc_test_link(struct zfcp_port *port)
{
	get_device(&port->dev);
	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
		put_device(&port->dev);
}

/**
 * zfcp_fc_sg_free_table - free memory used by scatterlists
 * @sg: pointer to scatterlist
 * @count: number of scatterlist which are to be free'ed
 * the scatterlist are expected to reference pages always
 */
static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
{
	int i;

	for (i = 0; i < count; i++, sg++)
		if (sg)
			free_page((unsigned long) sg_virt(sg));
		else
			break;
}

/**
 * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
 * @sg: pointer to struct scatterlist
 * @count: number of scatterlists which should be assigned with buffers
 * of size page
 *
 * Returns: 0 on success, -ENOMEM otherwise
 */
static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
{
	void *addr;
	int i;

	sg_init_table(sg, count);
	for (i = 0; i < count; i++, sg++) {
		addr = (void *) get_zeroed_page(GFP_KERNEL);
		if (!addr) {
			zfcp_fc_sg_free_table(sg, i);
			return -ENOMEM;
		}
		sg_set_buf(sg, addr, PAGE_SIZE);
	}
	return 0;
}

static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
{
	struct zfcp_fc_req *fc_req;

	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
	if (!fc_req)
		return NULL;

	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
		kmem_cache_free(zfcp_fc_req_cache, fc_req);
		return NULL;
	}

	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
		    sizeof(struct zfcp_fc_gpn_ft_req));

	return fc_req;
}

static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
			       struct zfcp_adapter *adapter, int max_bytes)
{
	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
	DECLARE_COMPLETION_ONSTACK(completion);
	int ret;

	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;

	ct_els->handler = zfcp_fc_complete;
	ct_els->handler_data = &completion;
	ct_els->req = &fc_req->sg_req;
	ct_els->resp = &fc_req->sg_rsp;

	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
			       ZFCP_FC_CTELS_TMO);
	if (!ret)
		wait_for_completion(&completion);
	return ret;
}

static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
{
	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
		return;

	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);

	if ((port->supported_classes != 0) ||
	    !list_empty(&port->unit_list))
		return;

	list_move_tail(&port->list, lh);
}

static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
			       struct zfcp_adapter *adapter, int max_entries)
{
	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
	struct scatterlist *sg = &fc_req->sg_rsp;
	struct fc_ct_hdr *hdr = sg_virt(sg);
	struct fc_gpn_ft_resp *acc = sg_virt(sg);
	struct zfcp_port *port, *tmp;
	unsigned long flags;
	LIST_HEAD(remove_lh);
	u32 d_id;
	int ret = 0, x, last = 0;

	if (ct_els->status)
		return -EIO;

	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
		if (hdr->ct_reason == FC_FS_RJT_UNABL)
			return -EAGAIN; /* might be a temporary condition */
		return -EIO;
	}

	if (hdr->ct_mr_size) {
		dev_warn(&adapter->ccw_device->dev,
			 "The name server reported %d words residual data\n",
			 hdr->ct_mr_size);
		return -E2BIG;
	}

	/* first entry is the header */
	for (x = 1; x < max_entries && !last; x++) {
		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
			acc++;
		else
			acc = sg_virt(++sg);

		last = acc->fp_flags & FC_NS_FID_LAST;
		d_id = ntoh24(acc->fp_fid);

		/* don't attach ports with a well known address */
		if (d_id >= FC_FID_WELL_KNOWN_BASE)
			continue;
		/* skip the adapter's port and known remote ports */
		if (be64_to_cpu(acc->fp_wwpn) ==
		    fc_host_port_name(adapter->scsi_host))
			continue;

		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
					 ZFCP_STATUS_COMMON_NOESC, d_id);
		if (!IS_ERR(port))
			zfcp_erp_port_reopen(port, 0, "fcegpf1");
		else if (PTR_ERR(port) != -EEXIST)
			ret = PTR_ERR(port);
	}

	zfcp_erp_wait(adapter);
	write_lock_irqsave(&adapter->port_list_lock, flags);
	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
		zfcp_fc_validate_port(port, &remove_lh);
	write_unlock_irqrestore(&adapter->port_list_lock, flags);

	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
		device_unregister(&port->dev);
	}

	return ret;
}

/**
 * zfcp_fc_scan_ports - scan remote ports and attach new ports
 * @work: reference to scheduled work
 */
void zfcp_fc_scan_ports(struct work_struct *work)
{
	struct delayed_work *dw = to_delayed_work(work);
	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
						    scan_work);
	int ret, i;
	struct zfcp_fc_req *fc_req;
	int chain, max_entries, buf_num, max_bytes;

	zfcp_fc_port_scan_time(adapter);

	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;

	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
		return;

	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
		return;

	fc_req = zfcp_fc_alloc_sg_env(buf_num);
	if (!fc_req)
		goto out;

	for (i = 0; i < 3; i++) {
		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
		if (!ret) {
			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
			if (ret == -EAGAIN)
				ssleep(1);
			else
				break;
		}
	}
	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
	kmem_cache_free(zfcp_fc_req_cache, fc_req);
out:
	zfcp_fc_wka_port_put(&adapter->gs->ds);
}

static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
			struct zfcp_fc_req *fc_req)
{
	DECLARE_COMPLETION_ONSTACK(completion);
	char devno[] = "DEVNO:";
	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
	int ret;

	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
			   FC_SYMBOLIC_NAME_SIZE);
	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));

	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));

	ct_els->handler = zfcp_fc_complete;
	ct_els->handler_data = &completion;
	ct_els->req = &fc_req->sg_req;
	ct_els->resp = &fc_req->sg_rsp;

	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
			       ZFCP_FC_CTELS_TMO);
	if (ret)
		return ret;

	wait_for_completion(&completion);
	if (ct_els->status)
		return ct_els->status;

	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
		snprintf(fc_host_symbolic_name(adapter->scsi_host),
			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
			 gspn_rsp->gspn.fp_name, devno,
			 dev_name(&adapter->ccw_device->dev),
			 init_utsname()->nodename);
	else
		strlcpy(fc_host_symbolic_name(adapter->scsi_host),
			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);

	return 0;
}

static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
			 struct zfcp_fc_req *fc_req)
{
	DECLARE_COMPLETION_ONSTACK(completion);
	struct Scsi_Host *shost = adapter->scsi_host;
	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
	int ret, len;

	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
			   FC_SYMBOLIC_NAME_SIZE);
	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
		      FC_SYMBOLIC_NAME_SIZE);
	rspn_req->rspn.fr_name_len = len;

	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));

	ct_els->handler = zfcp_fc_complete;
	ct_els->handler_data = &completion;
	ct_els->req = &fc_req->sg_req;
	ct_els->resp = &fc_req->sg_rsp;

	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
			       ZFCP_FC_CTELS_TMO);
	if (!ret)
		wait_for_completion(&completion);
}

/**
 * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
 * @work: ns_up_work of the adapter where to update the symbolic port name
 *
 * Retrieve the current symbolic port name that may have been set by
 * the hardware using the GSPN request and update the fc_host
 * symbolic_name sysfs attribute. When running in NPIV mode (and hence
 * the port name is unique for this system), update the symbolic port
 * name to add Linux specific information and update the FC nameserver
 * using the RSPN request.
 */
void zfcp_fc_sym_name_update(struct work_struct *work)
{
	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
						    ns_up_work);
	int ret;
	struct zfcp_fc_req *fc_req;

	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
		return;

	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
	if (!fc_req)
		return;

	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
	if (ret)
		goto out_free;

	ret = zfcp_fc_gspn(adapter, fc_req);
	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
		goto out_ds_put;

	memset(fc_req, 0, sizeof(*fc_req));
	zfcp_fc_rspn(adapter, fc_req);

out_ds_put:
	zfcp_fc_wka_port_put(&adapter->gs->ds);
out_free:
	kmem_cache_free(zfcp_fc_req_cache, fc_req);
}

static void zfcp_fc_ct_els_job_handler(void *data)
{
	struct bsg_job *job = data;
	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
	struct fc_bsg_reply *jr = job->reply;

	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
	jr->result = zfcp_ct_els->status ? -EIO : 0;
	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
}

static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
{
	u32 preamble_word1;
	u8 gs_type;
	struct zfcp_adapter *adapter;
	struct fc_bsg_request *bsg_request = job->request;
	struct fc_rport *rport = fc_bsg_to_rport(job);
	struct Scsi_Host *shost;

	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
	gs_type = (preamble_word1 & 0xff000000) >> 24;

	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
	adapter = (struct zfcp_adapter *) shost->hostdata[0];

	switch (gs_type) {
	case FC_FST_ALIAS:
		return &adapter->gs->as;
	case FC_FST_MGMT:
		return &adapter->gs->ms;
	case FC_FST_TIME:
		return &adapter->gs->ts;
		break;
	case FC_FST_DIR:
		return &adapter->gs->ds;
		break;
	default:
		return NULL;
	}
}

static void zfcp_fc_ct_job_handler(void *data)
{
	struct bsg_job *job = data;
	struct zfcp_fc_wka_port *wka_port;

	wka_port = zfcp_fc_job_wka_port(job);
	zfcp_fc_wka_port_put(wka_port);

	zfcp_fc_ct_els_job_handler(data);
}

static int zfcp_fc_exec_els_job(struct bsg_job *job,
				struct zfcp_adapter *adapter)
{
	struct zfcp_fsf_ct_els *els = job->dd_data;
	struct fc_rport *rport = fc_bsg_to_rport(job);
	struct fc_bsg_request *bsg_request = job->request;
	struct zfcp_port *port;
	u32 d_id;

	if (rport) {
		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
		if (!port)
			return -EINVAL;

		d_id = port->d_id;
		put_device(&port->dev);
	} else
		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);

	els->handler = zfcp_fc_ct_els_job_handler;
	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
}

static int zfcp_fc_exec_ct_job(struct bsg_job *job,
			       struct zfcp_adapter *adapter)
{
	int ret;
	struct zfcp_fsf_ct_els *ct = job->dd_data;
	struct zfcp_fc_wka_port *wka_port;

	wka_port = zfcp_fc_job_wka_port(job);
	if (!wka_port)
		return -EINVAL;

	ret = zfcp_fc_wka_port_get(wka_port);
	if (ret)
		return ret;

	ct->handler = zfcp_fc_ct_job_handler;
	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
	if (ret)
		zfcp_fc_wka_port_put(wka_port);

	return ret;
}

int zfcp_fc_exec_bsg_job(struct bsg_job *job)
{
	struct Scsi_Host *shost;
	struct zfcp_adapter *adapter;
	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
	struct fc_bsg_request *bsg_request = job->request;
	struct fc_rport *rport = fc_bsg_to_rport(job);

	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
	adapter = (struct zfcp_adapter *)shost->hostdata[0];

	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
		return -EINVAL;

	ct_els->req = job->request_payload.sg_list;
	ct_els->resp = job->reply_payload.sg_list;
	ct_els->handler_data = job;

	switch (bsg_request->msgcode) {
	case FC_BSG_RPT_ELS:
	case FC_BSG_HST_ELS_NOLOGIN:
		return zfcp_fc_exec_els_job(job, adapter);
	case FC_BSG_RPT_CT:
	case FC_BSG_HST_CT:
		return zfcp_fc_exec_ct_job(job, adapter);
	default:
		return -EINVAL;
	}
}

int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
{
	/* hardware tracks timeout, reset bsg timeout to not interfere */
	return -EAGAIN;
}

int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
{
	struct zfcp_fc_wka_ports *wka_ports;

	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
	if (!wka_ports)
		return -ENOMEM;

	adapter->gs = wka_ports;
	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);

	return 0;
}

void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
{
	kfree(adapter->gs);
	adapter->gs = NULL;
}