summaryrefslogtreecommitdiff
path: root/drivers/scsi/libfc/fc_rport.c
blob: a7175adab32dd4278967a0a49e276ed09f8d6a1b (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
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
/*
 * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Maintained at www.Open-FCoE.org
 */

/*
 * RPORT GENERAL INFO
 *
 * This file contains all processing regarding fc_rports. It contains the
 * rport state machine and does all rport interaction with the transport class.
 * There should be no other places in libfc that interact directly with the
 * transport class in regards to adding and deleting rports.
 *
 * fc_rport's represent N_Port's within the fabric.
 */

/*
 * RPORT LOCKING
 *
 * The rport should never hold the rport mutex and then attempt to acquire
 * either the lport or disc mutexes. The rport's mutex is considered lesser
 * than both the lport's mutex and the disc mutex. Refer to fc_lport.c for
 * more comments on the hierarchy.
 *
 * The locking strategy is similar to the lport's strategy. The lock protects
 * the rport's states and is held and released by the entry points to the rport
 * block. All _enter_* functions correspond to rport states and expect the rport
 * mutex to be locked before calling them. This means that rports only handle
 * one request or response at a time, since they're not critical for the I/O
 * path this potential over-use of the mutex is acceptable.
 */

#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/rcupdate.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <asm/unaligned.h>

#include <scsi/libfc.h>
#include <scsi/fc_encode.h>

#include "fc_libfc.h"

struct workqueue_struct *rport_event_queue;

static void fc_rport_enter_flogi(struct fc_rport_priv *);
static void fc_rport_enter_plogi(struct fc_rport_priv *);
static void fc_rport_enter_prli(struct fc_rport_priv *);
static void fc_rport_enter_rtv(struct fc_rport_priv *);
static void fc_rport_enter_ready(struct fc_rport_priv *);
static void fc_rport_enter_logo(struct fc_rport_priv *);
static void fc_rport_enter_adisc(struct fc_rport_priv *);

static void fc_rport_recv_plogi_req(struct fc_lport *, struct fc_frame *);
static void fc_rport_recv_prli_req(struct fc_rport_priv *, struct fc_frame *);
static void fc_rport_recv_prlo_req(struct fc_rport_priv *, struct fc_frame *);
static void fc_rport_recv_logo_req(struct fc_lport *, struct fc_frame *);
static void fc_rport_timeout(struct work_struct *);
static void fc_rport_error(struct fc_rport_priv *, struct fc_frame *);
static void fc_rport_error_retry(struct fc_rport_priv *, struct fc_frame *);
static void fc_rport_work(struct work_struct *);

static const char *fc_rport_state_names[] = {
	[RPORT_ST_INIT] = "Init",
	[RPORT_ST_FLOGI] = "FLOGI",
	[RPORT_ST_PLOGI_WAIT] = "PLOGI_WAIT",
	[RPORT_ST_PLOGI] = "PLOGI",
	[RPORT_ST_PRLI] = "PRLI",
	[RPORT_ST_RTV] = "RTV",
	[RPORT_ST_READY] = "Ready",
	[RPORT_ST_ADISC] = "ADISC",
	[RPORT_ST_DELETE] = "Delete",
};

/**
 * fc_rport_lookup() - Lookup a remote port by port_id
 * @lport:   The local port to lookup the remote port on
 * @port_id: The remote port ID to look up
 *
 * The caller must hold either disc_mutex or rcu_read_lock().
 */
static struct fc_rport_priv *fc_rport_lookup(const struct fc_lport *lport,
					     u32 port_id)
{
	struct fc_rport_priv *rdata;

	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers)
		if (rdata->ids.port_id == port_id)
			return rdata;
	return NULL;
}

/**
 * fc_rport_create() - Create a new remote port
 * @lport: The local port this remote port will be associated with
 * @ids:   The identifiers for the new remote port
 *
 * The remote port will start in the INIT state.
 *
 * Locking note:  must be called with the disc_mutex held.
 */
static struct fc_rport_priv *fc_rport_create(struct fc_lport *lport,
					     u32 port_id)
{
	struct fc_rport_priv *rdata;

	rdata = lport->tt.rport_lookup(lport, port_id);
	if (rdata)
		return rdata;

	rdata = kzalloc(sizeof(*rdata) + lport->rport_priv_size, GFP_KERNEL);
	if (!rdata)
		return NULL;

	rdata->ids.node_name = -1;
	rdata->ids.port_name = -1;
	rdata->ids.port_id = port_id;
	rdata->ids.roles = FC_RPORT_ROLE_UNKNOWN;

	kref_init(&rdata->kref);
	mutex_init(&rdata->rp_mutex);
	rdata->local_port = lport;
	rdata->rp_state = RPORT_ST_INIT;
	rdata->event = RPORT_EV_NONE;
	rdata->flags = FC_RP_FLAGS_REC_SUPPORTED;
	rdata->e_d_tov = lport->e_d_tov;
	rdata->r_a_tov = lport->r_a_tov;
	rdata->maxframe_size = FC_MIN_MAX_PAYLOAD;
	INIT_DELAYED_WORK(&rdata->retry_work, fc_rport_timeout);
	INIT_WORK(&rdata->event_work, fc_rport_work);
	if (port_id != FC_FID_DIR_SERV)
		list_add_rcu(&rdata->peers, &lport->disc.rports);
	return rdata;
}

/**
 * fc_rport_free_rcu() - Free a remote port
 * @rcu: The rcu_head structure inside the remote port
 */
static void fc_rport_free_rcu(struct rcu_head *rcu)
{
	struct fc_rport_priv *rdata;

	rdata = container_of(rcu, struct fc_rport_priv, rcu);
	kfree(rdata);
}

/**
 * fc_rport_destroy() - Free a remote port after last reference is released
 * @kref: The remote port's kref
 */
static void fc_rport_destroy(struct kref *kref)
{
	struct fc_rport_priv *rdata;

	rdata = container_of(kref, struct fc_rport_priv, kref);
	call_rcu(&rdata->rcu, fc_rport_free_rcu);
}

/**
 * fc_rport_state() - Return a string identifying the remote port's state
 * @rdata: The remote port
 */
static const char *fc_rport_state(struct fc_rport_priv *rdata)
{
	const char *cp;

	cp = fc_rport_state_names[rdata->rp_state];
	if (!cp)
		cp = "Unknown";
	return cp;
}

/**
 * fc_set_rport_loss_tmo() - Set the remote port loss timeout
 * @rport:   The remote port that gets a new timeout value
 * @timeout: The new timeout value (in seconds)
 */
void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout)
{
	if (timeout)
		rport->dev_loss_tmo = timeout;
	else
		rport->dev_loss_tmo = 1;
}
EXPORT_SYMBOL(fc_set_rport_loss_tmo);

/**
 * fc_plogi_get_maxframe() - Get the maximum payload from the common service
 *			     parameters in a FLOGI frame
 * @flp:    The FLOGI or PLOGI payload
 * @maxval: The maximum frame size upper limit; this may be less than what
 *	    is in the service parameters
 */
static unsigned int fc_plogi_get_maxframe(struct fc_els_flogi *flp,
					  unsigned int maxval)
{
	unsigned int mfs;

	/*
	 * Get max payload from the common service parameters and the
	 * class 3 receive data field size.
	 */
	mfs = ntohs(flp->fl_csp.sp_bb_data) & FC_SP_BB_DATA_MASK;
	if (mfs >= FC_SP_MIN_MAX_PAYLOAD && mfs < maxval)
		maxval = mfs;
	mfs = ntohs(flp->fl_cssp[3 - 1].cp_rdfs);
	if (mfs >= FC_SP_MIN_MAX_PAYLOAD && mfs < maxval)
		maxval = mfs;
	return maxval;
}

/**
 * fc_rport_state_enter() - Change the state of a remote port
 * @rdata: The remote port whose state should change
 * @new:   The new state
 *
 * Locking Note: Called with the rport lock held
 */
static void fc_rport_state_enter(struct fc_rport_priv *rdata,
				 enum fc_rport_state new)
{
	if (rdata->rp_state != new)
		rdata->retries = 0;
	rdata->rp_state = new;
}

/**
 * fc_rport_work() - Handler for remote port events in the rport_event_queue
 * @work: Handle to the remote port being dequeued
 */
static void fc_rport_work(struct work_struct *work)
{
	u32 port_id;
	struct fc_rport_priv *rdata =
		container_of(work, struct fc_rport_priv, event_work);
	struct fc_rport_libfc_priv *rpriv;
	enum fc_rport_event event;
	struct fc_lport *lport = rdata->local_port;
	struct fc_rport_operations *rport_ops;
	struct fc_rport_identifiers ids;
	struct fc_rport *rport;

	mutex_lock(&rdata->rp_mutex);
	event = rdata->event;
	rport_ops = rdata->ops;
	rport = rdata->rport;

	FC_RPORT_DBG(rdata, "work event %u\n", event);

	switch (event) {
	case RPORT_EV_READY:
		ids = rdata->ids;
		rdata->event = RPORT_EV_NONE;
		rdata->major_retries = 0;
		kref_get(&rdata->kref);
		mutex_unlock(&rdata->rp_mutex);

		if (!rport)
			rport = fc_remote_port_add(lport->host, 0, &ids);
		if (!rport) {
			FC_RPORT_DBG(rdata, "Failed to add the rport\n");
			lport->tt.rport_logoff(rdata);
			kref_put(&rdata->kref, lport->tt.rport_destroy);
			return;
		}
		mutex_lock(&rdata->rp_mutex);
		if (rdata->rport)
			FC_RPORT_DBG(rdata, "rport already allocated\n");
		rdata->rport = rport;
		rport->maxframe_size = rdata->maxframe_size;
		rport->supported_classes = rdata->supported_classes;

		rpriv = rport->dd_data;
		rpriv->local_port = lport;
		rpriv->rp_state = rdata->rp_state;
		rpriv->flags = rdata->flags;
		rpriv->e_d_tov = rdata->e_d_tov;
		rpriv->r_a_tov = rdata->r_a_tov;
		mutex_unlock(&rdata->rp_mutex);

		if (rport_ops && rport_ops->event_callback) {
			FC_RPORT_DBG(rdata, "callback ev %d\n", event);
			rport_ops->event_callback(lport, rdata, event);
		}
		kref_put(&rdata->kref, lport->tt.rport_destroy);
		break;

	case RPORT_EV_FAILED:
	case RPORT_EV_LOGO:
	case RPORT_EV_STOP:
		port_id = rdata->ids.port_id;
		mutex_unlock(&rdata->rp_mutex);

		if (rport_ops && rport_ops->event_callback) {
			FC_RPORT_DBG(rdata, "callback ev %d\n", event);
			rport_ops->event_callback(lport, rdata, event);
		}
		cancel_delayed_work_sync(&rdata->retry_work);

		/*
		 * Reset any outstanding exchanges before freeing rport.
		 */
		lport->tt.exch_mgr_reset(lport, 0, port_id);
		lport->tt.exch_mgr_reset(lport, port_id, 0);

		if (rport) {
			rpriv = rport->dd_data;
			rpriv->rp_state = RPORT_ST_DELETE;
			mutex_lock(&rdata->rp_mutex);
			rdata->rport = NULL;
			mutex_unlock(&rdata->rp_mutex);
			fc_remote_port_delete(rport);
		}

		mutex_lock(&lport->disc.disc_mutex);
		mutex_lock(&rdata->rp_mutex);
		if (rdata->rp_state == RPORT_ST_DELETE) {
			if (port_id == FC_FID_DIR_SERV) {
				rdata->event = RPORT_EV_NONE;
				mutex_unlock(&rdata->rp_mutex);
			} else if ((rdata->flags & FC_RP_STARTED) &&
				   rdata->major_retries <
				   lport->max_rport_retry_count) {
				rdata->major_retries++;
				rdata->event = RPORT_EV_NONE;
				FC_RPORT_DBG(rdata, "work restart\n");
				fc_rport_enter_flogi(rdata);
				mutex_unlock(&rdata->rp_mutex);
			} else {
				FC_RPORT_DBG(rdata, "work delete\n");
				list_del_rcu(&rdata->peers);
				mutex_unlock(&rdata->rp_mutex);
				kref_put(&rdata->kref, lport->tt.rport_destroy);
			}
		} else {
			/*
			 * Re-open for events.  Reissue READY event if ready.
			 */
			rdata->event = RPORT_EV_NONE;
			if (rdata->rp_state == RPORT_ST_READY)
				fc_rport_enter_ready(rdata);
			mutex_unlock(&rdata->rp_mutex);
		}
		mutex_unlock(&lport->disc.disc_mutex);
		break;

	default:
		mutex_unlock(&rdata->rp_mutex);
		break;
	}
}

/**
 * fc_rport_login() - Start the remote port login state machine
 * @rdata: The remote port to be logged in to
 *
 * Locking Note: Called without the rport lock held. This
 * function will hold the rport lock, call an _enter_*
 * function and then unlock the rport.
 *
 * This indicates the intent to be logged into the remote port.
 * If it appears we are already logged in, ADISC is used to verify
 * the setup.
 */
int fc_rport_login(struct fc_rport_priv *rdata)
{
	mutex_lock(&rdata->rp_mutex);

	rdata->flags |= FC_RP_STARTED;
	switch (rdata->rp_state) {
	case RPORT_ST_READY:
		FC_RPORT_DBG(rdata, "ADISC port\n");
		fc_rport_enter_adisc(rdata);
		break;
	case RPORT_ST_DELETE:
		FC_RPORT_DBG(rdata, "Restart deleted port\n");
		break;
	default:
		FC_RPORT_DBG(rdata, "Login to port\n");
		fc_rport_enter_flogi(rdata);
		break;
	}
	mutex_unlock(&rdata->rp_mutex);

	return 0;
}

/**
 * fc_rport_enter_delete() - Schedule a remote port to be deleted
 * @rdata: The remote port to be deleted
 * @event: The event to report as the reason for deletion
 *
 * Locking Note: Called with the rport lock held.
 *
 * Allow state change into DELETE only once.
 *
 * Call queue_work only if there's no event already pending.
 * Set the new event so that the old pending event will not occur.
 * Since we have the mutex, even if fc_rport_work() is already started,
 * it'll see the new event.
 */
static void fc_rport_enter_delete(struct fc_rport_priv *rdata,
				  enum fc_rport_event event)
{
	if (rdata->rp_state == RPORT_ST_DELETE)
		return;

	FC_RPORT_DBG(rdata, "Delete port\n");

	fc_rport_state_enter(rdata, RPORT_ST_DELETE);

	if (rdata->event == RPORT_EV_NONE)
		queue_work(rport_event_queue, &rdata->event_work);
	rdata->event = event;
}

/**
 * fc_rport_logoff() - Logoff and remove a remote port
 * @rdata: The remote port to be logged off of
 *
 * Locking Note: Called without the rport lock held. This
 * function will hold the rport lock, call an _enter_*
 * function and then unlock the rport.
 */
int fc_rport_logoff(struct fc_rport_priv *rdata)
{
	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Remove port\n");

	rdata->flags &= ~FC_RP_STARTED;
	if (rdata->rp_state == RPORT_ST_DELETE) {
		FC_RPORT_DBG(rdata, "Port in Delete state, not removing\n");
		goto out;
	}
	fc_rport_enter_logo(rdata);

	/*
	 * Change the state to Delete so that we discard
	 * the response.
	 */
	fc_rport_enter_delete(rdata, RPORT_EV_STOP);
out:
	mutex_unlock(&rdata->rp_mutex);
	return 0;
}

/**
 * fc_rport_enter_ready() - Transition to the RPORT_ST_READY state
 * @rdata: The remote port that is ready
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_ready(struct fc_rport_priv *rdata)
{
	fc_rport_state_enter(rdata, RPORT_ST_READY);

	FC_RPORT_DBG(rdata, "Port is Ready\n");

	if (rdata->event == RPORT_EV_NONE)
		queue_work(rport_event_queue, &rdata->event_work);
	rdata->event = RPORT_EV_READY;
}

/**
 * fc_rport_timeout() - Handler for the retry_work timer
 * @work: Handle to the remote port that has timed out
 *
 * Locking Note: Called without the rport lock held. This
 * function will hold the rport lock, call an _enter_*
 * function and then unlock the rport.
 */
static void fc_rport_timeout(struct work_struct *work)
{
	struct fc_rport_priv *rdata =
		container_of(work, struct fc_rport_priv, retry_work.work);

	mutex_lock(&rdata->rp_mutex);

	switch (rdata->rp_state) {
	case RPORT_ST_FLOGI:
		fc_rport_enter_flogi(rdata);
		break;
	case RPORT_ST_PLOGI:
		fc_rport_enter_plogi(rdata);
		break;
	case RPORT_ST_PRLI:
		fc_rport_enter_prli(rdata);
		break;
	case RPORT_ST_RTV:
		fc_rport_enter_rtv(rdata);
		break;
	case RPORT_ST_ADISC:
		fc_rport_enter_adisc(rdata);
		break;
	case RPORT_ST_PLOGI_WAIT:
	case RPORT_ST_READY:
	case RPORT_ST_INIT:
	case RPORT_ST_DELETE:
		break;
	}

	mutex_unlock(&rdata->rp_mutex);
}

/**
 * fc_rport_error() - Error handler, called once retries have been exhausted
 * @rdata: The remote port the error is happened on
 * @fp:	   The error code encapsulated in a frame pointer
 *
 * Locking Note: The rport lock is expected to be held before
 * calling this routine
 */
static void fc_rport_error(struct fc_rport_priv *rdata, struct fc_frame *fp)
{
	FC_RPORT_DBG(rdata, "Error %ld in state %s, retries %d\n",
		     IS_ERR(fp) ? -PTR_ERR(fp) : 0,
		     fc_rport_state(rdata), rdata->retries);

	switch (rdata->rp_state) {
	case RPORT_ST_FLOGI:
	case RPORT_ST_PLOGI:
		rdata->flags &= ~FC_RP_STARTED;
		fc_rport_enter_delete(rdata, RPORT_EV_FAILED);
		break;
	case RPORT_ST_RTV:
		fc_rport_enter_ready(rdata);
		break;
	case RPORT_ST_PRLI:
	case RPORT_ST_ADISC:
		fc_rport_enter_logo(rdata);
		break;
	case RPORT_ST_PLOGI_WAIT:
	case RPORT_ST_DELETE:
	case RPORT_ST_READY:
	case RPORT_ST_INIT:
		break;
	}
}

/**
 * fc_rport_error_retry() - Handler for remote port state retries
 * @rdata: The remote port whose state is to be retried
 * @fp:	   The error code encapsulated in a frame pointer
 *
 * If the error was an exchange timeout retry immediately,
 * otherwise wait for E_D_TOV.
 *
 * Locking Note: The rport lock is expected to be held before
 * calling this routine
 */
static void fc_rport_error_retry(struct fc_rport_priv *rdata,
				 struct fc_frame *fp)
{
	unsigned long delay = FC_DEF_E_D_TOV;

	/* make sure this isn't an FC_EX_CLOSED error, never retry those */
	if (PTR_ERR(fp) == -FC_EX_CLOSED)
		return fc_rport_error(rdata, fp);

	if (rdata->retries < rdata->local_port->max_rport_retry_count) {
		FC_RPORT_DBG(rdata, "Error %ld in state %s, retrying\n",
			     PTR_ERR(fp), fc_rport_state(rdata));
		rdata->retries++;
		/* no additional delay on exchange timeouts */
		if (PTR_ERR(fp) == -FC_EX_TIMEOUT)
			delay = 0;
		schedule_delayed_work(&rdata->retry_work, delay);
		return;
	}

	return fc_rport_error(rdata, fp);
}

/**
 * fc_rport_login_complete() - Handle parameters and completion of p-mp login.
 * @rdata:  The remote port which we logged into or which logged into us.
 * @fp:     The FLOGI or PLOGI request or response frame
 *
 * Returns non-zero error if a problem is detected with the frame.
 * Does not free the frame.
 *
 * This is only used in point-to-multipoint mode for FIP currently.
 */
static int fc_rport_login_complete(struct fc_rport_priv *rdata,
				   struct fc_frame *fp)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_els_flogi *flogi;
	unsigned int e_d_tov;
	u16 csp_flags;

	flogi = fc_frame_payload_get(fp, sizeof(*flogi));
	if (!flogi)
		return -EINVAL;

	csp_flags = ntohs(flogi->fl_csp.sp_features);

	if (fc_frame_payload_op(fp) == ELS_FLOGI) {
		if (csp_flags & FC_SP_FT_FPORT) {
			FC_RPORT_DBG(rdata, "Fabric bit set in FLOGI\n");
			return -EINVAL;
		}
	} else {

		/*
		 * E_D_TOV is not valid on an incoming FLOGI request.
		 */
		e_d_tov = ntohl(flogi->fl_csp.sp_e_d_tov);
		if (csp_flags & FC_SP_FT_EDTR)
			e_d_tov /= 1000000;
		if (e_d_tov > rdata->e_d_tov)
			rdata->e_d_tov = e_d_tov;
	}
	rdata->maxframe_size = fc_plogi_get_maxframe(flogi, lport->mfs);
	return 0;
}

/**
 * fc_rport_flogi_resp() - Handle response to FLOGI request for p-mp mode
 * @sp:	    The sequence that the FLOGI was on
 * @fp:	    The FLOGI response frame
 * @rp_arg: The remote port that received the FLOGI response
 */
void fc_rport_flogi_resp(struct fc_seq *sp, struct fc_frame *fp,
			 void *rp_arg)
{
	struct fc_rport_priv *rdata = rp_arg;
	struct fc_lport *lport = rdata->local_port;
	struct fc_els_flogi *flogi;
	unsigned int r_a_tov;

	FC_RPORT_DBG(rdata, "Received a FLOGI %s\n", fc_els_resp_type(fp));

	if (fp == ERR_PTR(-FC_EX_CLOSED))
		goto put;

	mutex_lock(&rdata->rp_mutex);

	if (rdata->rp_state != RPORT_ST_FLOGI) {
		FC_RPORT_DBG(rdata, "Received a FLOGI response, but in state "
			     "%s\n", fc_rport_state(rdata));
		if (IS_ERR(fp))
			goto err;
		goto out;
	}

	if (IS_ERR(fp)) {
		fc_rport_error(rdata, fp);
		goto err;
	}

	if (fc_frame_payload_op(fp) != ELS_LS_ACC)
		goto bad;
	if (fc_rport_login_complete(rdata, fp))
		goto bad;

	flogi = fc_frame_payload_get(fp, sizeof(*flogi));
	if (!flogi)
		goto bad;
	r_a_tov = ntohl(flogi->fl_csp.sp_r_a_tov);
	if (r_a_tov > rdata->r_a_tov)
		rdata->r_a_tov = r_a_tov;

	if (rdata->ids.port_name < lport->wwpn)
		fc_rport_enter_plogi(rdata);
	else
		fc_rport_state_enter(rdata, RPORT_ST_PLOGI_WAIT);
out:
	fc_frame_free(fp);
err:
	mutex_unlock(&rdata->rp_mutex);
put:
	kref_put(&rdata->kref, rdata->local_port->tt.rport_destroy);
	return;
bad:
	FC_RPORT_DBG(rdata, "Bad FLOGI response\n");
	fc_rport_error_retry(rdata, fp);
	goto out;
}

/**
 * fc_rport_enter_flogi() - Send a FLOGI request to the remote port for p-mp
 * @rdata: The remote port to send a FLOGI to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_flogi(struct fc_rport_priv *rdata)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;

	if (!lport->point_to_multipoint)
		return fc_rport_enter_plogi(rdata);

	FC_RPORT_DBG(rdata, "Entered FLOGI state from %s state\n",
		     fc_rport_state(rdata));

	fc_rport_state_enter(rdata, RPORT_ST_FLOGI);

	fp = fc_frame_alloc(lport, sizeof(struct fc_els_flogi));
	if (!fp)
		return fc_rport_error_retry(rdata, fp);

	if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_FLOGI,
				  fc_rport_flogi_resp, rdata,
				  2 * lport->r_a_tov))
		fc_rport_error_retry(rdata, NULL);
	else
		kref_get(&rdata->kref);
}

/**
 * fc_rport_recv_flogi_req() - Handle Fabric Login (FLOGI) request in p-mp mode
 * @lport: The local port that received the PLOGI request
 * @rx_fp: The PLOGI request frame
 */
static void fc_rport_recv_flogi_req(struct fc_lport *lport,
				    struct fc_frame *rx_fp)
{
	struct fc_disc *disc;
	struct fc_els_flogi *flp;
	struct fc_rport_priv *rdata;
	struct fc_frame *fp = rx_fp;
	struct fc_seq_els_data rjt_data;
	u32 sid;

	sid = fc_frame_sid(fp);

	FC_RPORT_ID_DBG(lport, sid, "Received FLOGI request\n");

	disc = &lport->disc;
	mutex_lock(&disc->disc_mutex);

	if (!lport->point_to_multipoint) {
		rjt_data.reason = ELS_RJT_UNSUP;
		rjt_data.explan = ELS_EXPL_NONE;
		goto reject;
	}

	flp = fc_frame_payload_get(fp, sizeof(*flp));
	if (!flp) {
		rjt_data.reason = ELS_RJT_LOGIC;
		rjt_data.explan = ELS_EXPL_INV_LEN;
		goto reject;
	}

	rdata = lport->tt.rport_lookup(lport, sid);
	if (!rdata) {
		rjt_data.reason = ELS_RJT_FIP;
		rjt_data.explan = ELS_EXPL_NOT_NEIGHBOR;
		goto reject;
	}
	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Received FLOGI in %s state\n",
		     fc_rport_state(rdata));

	switch (rdata->rp_state) {
	case RPORT_ST_INIT:
	case RPORT_ST_DELETE:
		mutex_unlock(&rdata->rp_mutex);
		rjt_data.reason = ELS_RJT_FIP;
		rjt_data.explan = ELS_EXPL_NOT_NEIGHBOR;
		goto reject;
	case RPORT_ST_FLOGI:
	case RPORT_ST_PLOGI_WAIT:
	case RPORT_ST_PLOGI:
		break;
	case RPORT_ST_PRLI:
	case RPORT_ST_RTV:
	case RPORT_ST_READY:
	case RPORT_ST_ADISC:
		/*
		 * Set the remote port to be deleted and to then restart.
		 * This queues work to be sure exchanges are reset.
		 */
		fc_rport_enter_delete(rdata, RPORT_EV_LOGO);
		mutex_unlock(&rdata->rp_mutex);
		rjt_data.reason = ELS_RJT_BUSY;
		rjt_data.explan = ELS_EXPL_NONE;
		goto reject;
	}
	if (fc_rport_login_complete(rdata, fp)) {
		mutex_unlock(&rdata->rp_mutex);
		rjt_data.reason = ELS_RJT_LOGIC;
		rjt_data.explan = ELS_EXPL_NONE;
		goto reject;
	}

	fp = fc_frame_alloc(lport, sizeof(*flp));
	if (!fp)
		goto out;

	fc_flogi_fill(lport, fp);
	flp = fc_frame_payload_get(fp, sizeof(*flp));
	flp->fl_cmd = ELS_LS_ACC;

	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);

	if (rdata->ids.port_name < lport->wwpn)
		fc_rport_enter_plogi(rdata);
	else
		fc_rport_state_enter(rdata, RPORT_ST_PLOGI_WAIT);
out:
	mutex_unlock(&rdata->rp_mutex);
	mutex_unlock(&disc->disc_mutex);
	fc_frame_free(rx_fp);
	return;

reject:
	mutex_unlock(&disc->disc_mutex);
	lport->tt.seq_els_rsp_send(rx_fp, ELS_LS_RJT, &rjt_data);
	fc_frame_free(rx_fp);
}

/**
 * fc_rport_plogi_resp() - Handler for ELS PLOGI responses
 * @sp:	       The sequence the PLOGI is on
 * @fp:	       The PLOGI response frame
 * @rdata_arg: The remote port that sent the PLOGI response
 *
 * Locking Note: This function will be called without the rport lock
 * held, but it will lock, call an _enter_* function or fc_rport_error
 * and then unlock the rport.
 */
static void fc_rport_plogi_resp(struct fc_seq *sp, struct fc_frame *fp,
				void *rdata_arg)
{
	struct fc_rport_priv *rdata = rdata_arg;
	struct fc_lport *lport = rdata->local_port;
	struct fc_els_flogi *plp = NULL;
	u16 csp_seq;
	u16 cssp_seq;
	u8 op;

	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Received a PLOGI %s\n", fc_els_resp_type(fp));

	if (rdata->rp_state != RPORT_ST_PLOGI) {
		FC_RPORT_DBG(rdata, "Received a PLOGI response, but in state "
			     "%s\n", fc_rport_state(rdata));
		if (IS_ERR(fp))
			goto err;
		goto out;
	}

	if (IS_ERR(fp)) {
		fc_rport_error_retry(rdata, fp);
		goto err;
	}

	op = fc_frame_payload_op(fp);
	if (op == ELS_LS_ACC &&
	    (plp = fc_frame_payload_get(fp, sizeof(*plp))) != NULL) {
		rdata->ids.port_name = get_unaligned_be64(&plp->fl_wwpn);
		rdata->ids.node_name = get_unaligned_be64(&plp->fl_wwnn);

		if (lport->point_to_multipoint)
			fc_rport_login_complete(rdata, fp);
		csp_seq = ntohs(plp->fl_csp.sp_tot_seq);
		cssp_seq = ntohs(plp->fl_cssp[3 - 1].cp_con_seq);
		if (cssp_seq < csp_seq)
			csp_seq = cssp_seq;
		rdata->max_seq = csp_seq;
		rdata->maxframe_size = fc_plogi_get_maxframe(plp, lport->mfs);
		fc_rport_enter_prli(rdata);
	} else
		fc_rport_error_retry(rdata, fp);

out:
	fc_frame_free(fp);
err:
	mutex_unlock(&rdata->rp_mutex);
	kref_put(&rdata->kref, rdata->local_port->tt.rport_destroy);
}

/**
 * fc_rport_enter_plogi() - Send Port Login (PLOGI) request
 * @rdata: The remote port to send a PLOGI to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_plogi(struct fc_rport_priv *rdata)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;

	FC_RPORT_DBG(rdata, "Port entered PLOGI state from %s state\n",
		     fc_rport_state(rdata));

	fc_rport_state_enter(rdata, RPORT_ST_PLOGI);

	rdata->maxframe_size = FC_MIN_MAX_PAYLOAD;
	fp = fc_frame_alloc(lport, sizeof(struct fc_els_flogi));
	if (!fp) {
		FC_RPORT_DBG(rdata, "%s frame alloc failed\n", __func__);
		fc_rport_error_retry(rdata, fp);
		return;
	}
	rdata->e_d_tov = lport->e_d_tov;

	if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_PLOGI,
				  fc_rport_plogi_resp, rdata,
				  2 * lport->r_a_tov))
		fc_rport_error_retry(rdata, NULL);
	else
		kref_get(&rdata->kref);
}

/**
 * fc_rport_prli_resp() - Process Login (PRLI) response handler
 * @sp:	       The sequence the PRLI response was on
 * @fp:	       The PRLI response frame
 * @rdata_arg: The remote port that sent the PRLI response
 *
 * Locking Note: This function will be called without the rport lock
 * held, but it will lock, call an _enter_* function or fc_rport_error
 * and then unlock the rport.
 */
static void fc_rport_prli_resp(struct fc_seq *sp, struct fc_frame *fp,
			       void *rdata_arg)
{
	struct fc_rport_priv *rdata = rdata_arg;
	struct {
		struct fc_els_prli prli;
		struct fc_els_spp spp;
	} *pp;
	u32 roles = FC_RPORT_ROLE_UNKNOWN;
	u32 fcp_parm = 0;
	u8 op;
	u8 resp_code = 0;

	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Received a PRLI %s\n", fc_els_resp_type(fp));

	if (rdata->rp_state != RPORT_ST_PRLI) {
		FC_RPORT_DBG(rdata, "Received a PRLI response, but in state "
			     "%s\n", fc_rport_state(rdata));
		if (IS_ERR(fp))
			goto err;
		goto out;
	}

	if (IS_ERR(fp)) {
		fc_rport_error_retry(rdata, fp);
		goto err;
	}

	/* reinitialize remote port roles */
	rdata->ids.roles = FC_RPORT_ROLE_UNKNOWN;

	op = fc_frame_payload_op(fp);
	if (op == ELS_LS_ACC) {
		pp = fc_frame_payload_get(fp, sizeof(*pp));
		if (!pp)
			goto out;

		resp_code = (pp->spp.spp_flags & FC_SPP_RESP_MASK);
		FC_RPORT_DBG(rdata, "PRLI spp_flags = 0x%x\n",
			     pp->spp.spp_flags);
		if (resp_code != FC_SPP_RESP_ACK) {
			if (resp_code == FC_SPP_RESP_CONF)
				fc_rport_error(rdata, fp);
			else
				fc_rport_error_retry(rdata, fp);
			goto out;
		}
		if (pp->prli.prli_spp_len < sizeof(pp->spp))
			goto out;

		fcp_parm = ntohl(pp->spp.spp_params);
		if (fcp_parm & FCP_SPPF_RETRY)
			rdata->flags |= FC_RP_FLAGS_RETRY;

		rdata->supported_classes = FC_COS_CLASS3;
		if (fcp_parm & FCP_SPPF_INIT_FCN)
			roles |= FC_RPORT_ROLE_FCP_INITIATOR;
		if (fcp_parm & FCP_SPPF_TARG_FCN)
			roles |= FC_RPORT_ROLE_FCP_TARGET;

		rdata->ids.roles = roles;
		fc_rport_enter_rtv(rdata);

	} else {
		FC_RPORT_DBG(rdata, "Bad ELS response for PRLI command\n");
		fc_rport_error_retry(rdata, fp);
	}

out:
	fc_frame_free(fp);
err:
	mutex_unlock(&rdata->rp_mutex);
	kref_put(&rdata->kref, rdata->local_port->tt.rport_destroy);
}

/**
 * fc_rport_enter_prli() - Send Process Login (PRLI) request
 * @rdata: The remote port to send the PRLI request to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_prli(struct fc_rport_priv *rdata)
{
	struct fc_lport *lport = rdata->local_port;
	struct {
		struct fc_els_prli prli;
		struct fc_els_spp spp;
	} *pp;
	struct fc_frame *fp;

	/*
	 * If the rport is one of the well known addresses
	 * we skip PRLI and RTV and go straight to READY.
	 */
	if (rdata->ids.port_id >= FC_FID_DOM_MGR) {
		fc_rport_enter_ready(rdata);
		return;
	}

	FC_RPORT_DBG(rdata, "Port entered PRLI state from %s state\n",
		     fc_rport_state(rdata));

	fc_rport_state_enter(rdata, RPORT_ST_PRLI);

	fp = fc_frame_alloc(lport, sizeof(*pp));
	if (!fp) {
		fc_rport_error_retry(rdata, fp);
		return;
	}

	if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_PRLI,
				  fc_rport_prli_resp, rdata,
				  2 * lport->r_a_tov))
		fc_rport_error_retry(rdata, NULL);
	else
		kref_get(&rdata->kref);
}

/**
 * fc_rport_els_rtv_resp() - Handler for Request Timeout Value (RTV) responses
 * @sp:	       The sequence the RTV was on
 * @fp:	       The RTV response frame
 * @rdata_arg: The remote port that sent the RTV response
 *
 * Many targets don't seem to support this.
 *
 * Locking Note: This function will be called without the rport lock
 * held, but it will lock, call an _enter_* function or fc_rport_error
 * and then unlock the rport.
 */
static void fc_rport_rtv_resp(struct fc_seq *sp, struct fc_frame *fp,
			      void *rdata_arg)
{
	struct fc_rport_priv *rdata = rdata_arg;
	u8 op;

	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Received a RTV %s\n", fc_els_resp_type(fp));

	if (rdata->rp_state != RPORT_ST_RTV) {
		FC_RPORT_DBG(rdata, "Received a RTV response, but in state "
			     "%s\n", fc_rport_state(rdata));
		if (IS_ERR(fp))
			goto err;
		goto out;
	}

	if (IS_ERR(fp)) {
		fc_rport_error(rdata, fp);
		goto err;
	}

	op = fc_frame_payload_op(fp);
	if (op == ELS_LS_ACC) {
		struct fc_els_rtv_acc *rtv;
		u32 toq;
		u32 tov;

		rtv = fc_frame_payload_get(fp, sizeof(*rtv));
		if (rtv) {
			toq = ntohl(rtv->rtv_toq);
			tov = ntohl(rtv->rtv_r_a_tov);
			if (tov == 0)
				tov = 1;
			rdata->r_a_tov = tov;
			tov = ntohl(rtv->rtv_e_d_tov);
			if (toq & FC_ELS_RTV_EDRES)
				tov /= 1000000;
			if (tov == 0)
				tov = 1;
			rdata->e_d_tov = tov;
		}
	}

	fc_rport_enter_ready(rdata);

out:
	fc_frame_free(fp);
err:
	mutex_unlock(&rdata->rp_mutex);
	kref_put(&rdata->kref, rdata->local_port->tt.rport_destroy);
}

/**
 * fc_rport_enter_rtv() - Send Request Timeout Value (RTV) request
 * @rdata: The remote port to send the RTV request to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_rtv(struct fc_rport_priv *rdata)
{
	struct fc_frame *fp;
	struct fc_lport *lport = rdata->local_port;

	FC_RPORT_DBG(rdata, "Port entered RTV state from %s state\n",
		     fc_rport_state(rdata));

	fc_rport_state_enter(rdata, RPORT_ST_RTV);

	fp = fc_frame_alloc(lport, sizeof(struct fc_els_rtv));
	if (!fp) {
		fc_rport_error_retry(rdata, fp);
		return;
	}

	if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_RTV,
				  fc_rport_rtv_resp, rdata,
				  2 * lport->r_a_tov))
		fc_rport_error_retry(rdata, NULL);
	else
		kref_get(&rdata->kref);
}

/**
 * fc_rport_logo_resp() - Handler for logout (LOGO) responses
 * @sp:	       The sequence the LOGO was on
 * @fp:	       The LOGO response frame
 * @lport_arg: The local port
 */
static void fc_rport_logo_resp(struct fc_seq *sp, struct fc_frame *fp,
			       void *lport_arg)
{
	struct fc_lport *lport = lport_arg;

	FC_RPORT_ID_DBG(lport, fc_seq_exch(sp)->did,
			"Received a LOGO %s\n", fc_els_resp_type(fp));
	if (IS_ERR(fp))
		return;
	fc_frame_free(fp);
}

/**
 * fc_rport_enter_logo() - Send a logout (LOGO) request
 * @rdata: The remote port to send the LOGO request to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_logo(struct fc_rport_priv *rdata)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;

	FC_RPORT_DBG(rdata, "Port sending LOGO from %s state\n",
		     fc_rport_state(rdata));

	fp = fc_frame_alloc(lport, sizeof(struct fc_els_logo));
	if (!fp)
		return;
	(void)lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_LOGO,
				   fc_rport_logo_resp, lport, 0);
}

/**
 * fc_rport_els_adisc_resp() - Handler for Address Discovery (ADISC) responses
 * @sp:	       The sequence the ADISC response was on
 * @fp:	       The ADISC response frame
 * @rdata_arg: The remote port that sent the ADISC response
 *
 * Locking Note: This function will be called without the rport lock
 * held, but it will lock, call an _enter_* function or fc_rport_error
 * and then unlock the rport.
 */
static void fc_rport_adisc_resp(struct fc_seq *sp, struct fc_frame *fp,
				void *rdata_arg)
{
	struct fc_rport_priv *rdata = rdata_arg;
	struct fc_els_adisc *adisc;
	u8 op;

	mutex_lock(&rdata->rp_mutex);

	FC_RPORT_DBG(rdata, "Received a ADISC response\n");

	if (rdata->rp_state != RPORT_ST_ADISC) {
		FC_RPORT_DBG(rdata, "Received a ADISC resp but in state %s\n",
			     fc_rport_state(rdata));
		if (IS_ERR(fp))
			goto err;
		goto out;
	}

	if (IS_ERR(fp)) {
		fc_rport_error(rdata, fp);
		goto err;
	}

	/*
	 * If address verification failed.  Consider us logged out of the rport.
	 * Since the rport is still in discovery, we want to be
	 * logged in, so go to PLOGI state.  Otherwise, go back to READY.
	 */
	op = fc_frame_payload_op(fp);
	adisc = fc_frame_payload_get(fp, sizeof(*adisc));
	if (op != ELS_LS_ACC || !adisc ||
	    ntoh24(adisc->adisc_port_id) != rdata->ids.port_id ||
	    get_unaligned_be64(&adisc->adisc_wwpn) != rdata->ids.port_name ||
	    get_unaligned_be64(&adisc->adisc_wwnn) != rdata->ids.node_name) {
		FC_RPORT_DBG(rdata, "ADISC error or mismatch\n");
		fc_rport_enter_flogi(rdata);
	} else {
		FC_RPORT_DBG(rdata, "ADISC OK\n");
		fc_rport_enter_ready(rdata);
	}
out:
	fc_frame_free(fp);
err:
	mutex_unlock(&rdata->rp_mutex);
	kref_put(&rdata->kref, rdata->local_port->tt.rport_destroy);
}

/**
 * fc_rport_enter_adisc() - Send Address Discover (ADISC) request
 * @rdata: The remote port to send the ADISC request to
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this routine.
 */
static void fc_rport_enter_adisc(struct fc_rport_priv *rdata)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;

	FC_RPORT_DBG(rdata, "sending ADISC from %s state\n",
		     fc_rport_state(rdata));

	fc_rport_state_enter(rdata, RPORT_ST_ADISC);

	fp = fc_frame_alloc(lport, sizeof(struct fc_els_adisc));
	if (!fp) {
		fc_rport_error_retry(rdata, fp);
		return;
	}
	if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, ELS_ADISC,
				  fc_rport_adisc_resp, rdata,
				  2 * lport->r_a_tov))
		fc_rport_error_retry(rdata, NULL);
	else
		kref_get(&rdata->kref);
}

/**
 * fc_rport_recv_adisc_req() - Handler for Address Discovery (ADISC) requests
 * @rdata: The remote port that sent the ADISC request
 * @in_fp: The ADISC request frame
 *
 * Locking Note:  Called with the lport and rport locks held.
 */
static void fc_rport_recv_adisc_req(struct fc_rport_priv *rdata,
				    struct fc_frame *in_fp)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;
	struct fc_els_adisc *adisc;
	struct fc_seq_els_data rjt_data;

	FC_RPORT_DBG(rdata, "Received ADISC request\n");

	adisc = fc_frame_payload_get(in_fp, sizeof(*adisc));
	if (!adisc) {
		rjt_data.reason = ELS_RJT_PROT;
		rjt_data.explan = ELS_EXPL_INV_LEN;
		lport->tt.seq_els_rsp_send(in_fp, ELS_LS_RJT, &rjt_data);
		goto drop;
	}

	fp = fc_frame_alloc(lport, sizeof(*adisc));
	if (!fp)
		goto drop;
	fc_adisc_fill(lport, fp);
	adisc = fc_frame_payload_get(fp, sizeof(*adisc));
	adisc->adisc_cmd = ELS_LS_ACC;
	fc_fill_reply_hdr(fp, in_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);
drop:
	fc_frame_free(in_fp);
}

/**
 * fc_rport_recv_rls_req() - Handle received Read Link Status request
 * @rdata: The remote port that sent the RLS request
 * @rx_fp: The PRLI request frame
 *
 * Locking Note: The rport lock is expected to be held before calling
 * this function.
 */
static void fc_rport_recv_rls_req(struct fc_rport_priv *rdata,
				  struct fc_frame *rx_fp)

{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;
	struct fc_els_rls *rls;
	struct fc_els_rls_resp *rsp;
	struct fc_els_lesb *lesb;
	struct fc_seq_els_data rjt_data;
	struct fc_host_statistics *hst;

	FC_RPORT_DBG(rdata, "Received RLS request while in state %s\n",
		     fc_rport_state(rdata));

	rls = fc_frame_payload_get(rx_fp, sizeof(*rls));
	if (!rls) {
		rjt_data.reason = ELS_RJT_PROT;
		rjt_data.explan = ELS_EXPL_INV_LEN;
		goto out_rjt;
	}

	fp = fc_frame_alloc(lport, sizeof(*rsp));
	if (!fp) {
		rjt_data.reason = ELS_RJT_UNAB;
		rjt_data.explan = ELS_EXPL_INSUF_RES;
		goto out_rjt;
	}

	rsp = fc_frame_payload_get(fp, sizeof(*rsp));
	memset(rsp, 0, sizeof(*rsp));
	rsp->rls_cmd = ELS_LS_ACC;
	lesb = &rsp->rls_lesb;
	if (lport->tt.get_lesb) {
		/* get LESB from LLD if it supports it */
		lport->tt.get_lesb(lport, lesb);
	} else {
		fc_get_host_stats(lport->host);
		hst = &lport->host_stats;
		lesb->lesb_link_fail = htonl(hst->link_failure_count);
		lesb->lesb_sync_loss = htonl(hst->loss_of_sync_count);
		lesb->lesb_sig_loss = htonl(hst->loss_of_signal_count);
		lesb->lesb_prim_err = htonl(hst->prim_seq_protocol_err_count);
		lesb->lesb_inv_word = htonl(hst->invalid_tx_word_count);
		lesb->lesb_inv_crc = htonl(hst->invalid_crc_count);
	}

	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);
	goto out;

out_rjt:
	lport->tt.seq_els_rsp_send(rx_fp, ELS_LS_RJT, &rjt_data);
out:
	fc_frame_free(rx_fp);
}

/**
 * fc_rport_recv_els_req() - Handler for validated ELS requests
 * @lport: The local port that received the ELS request
 * @fp:	   The ELS request frame
 *
 * Handle incoming ELS requests that require port login.
 * The ELS opcode has already been validated by the caller.
 *
 * Locking Note: Called with the lport lock held.
 */
static void fc_rport_recv_els_req(struct fc_lport *lport, struct fc_frame *fp)
{
	struct fc_rport_priv *rdata;
	struct fc_seq_els_data els_data;

	mutex_lock(&lport->disc.disc_mutex);
	rdata = lport->tt.rport_lookup(lport, fc_frame_sid(fp));
	if (!rdata) {
		mutex_unlock(&lport->disc.disc_mutex);
		goto reject;
	}
	mutex_lock(&rdata->rp_mutex);
	mutex_unlock(&lport->disc.disc_mutex);

	switch (rdata->rp_state) {
	case RPORT_ST_PRLI:
	case RPORT_ST_RTV:
	case RPORT_ST_READY:
	case RPORT_ST_ADISC:
		break;
	default:
		mutex_unlock(&rdata->rp_mutex);
		goto reject;
	}

	switch (fc_frame_payload_op(fp)) {
	case ELS_PRLI:
		fc_rport_recv_prli_req(rdata, fp);
		break;
	case ELS_PRLO:
		fc_rport_recv_prlo_req(rdata, fp);
		break;
	case ELS_ADISC:
		fc_rport_recv_adisc_req(rdata, fp);
		break;
	case ELS_RRQ:
		lport->tt.seq_els_rsp_send(fp, ELS_RRQ, NULL);
		fc_frame_free(fp);
		break;
	case ELS_REC:
		lport->tt.seq_els_rsp_send(fp, ELS_REC, NULL);
		fc_frame_free(fp);
		break;
	case ELS_RLS:
		fc_rport_recv_rls_req(rdata, fp);
		break;
	default:
		fc_frame_free(fp);	/* can't happen */
		break;
	}

	mutex_unlock(&rdata->rp_mutex);
	return;

reject:
	els_data.reason = ELS_RJT_UNAB;
	els_data.explan = ELS_EXPL_PLOGI_REQD;
	lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &els_data);
	fc_frame_free(fp);
}

/**
 * fc_rport_recv_req() - Handler for requests
 * @lport: The local port that received the request
 * @fp:	   The request frame
 *
 * Locking Note: Called with the lport lock held.
 */
void fc_rport_recv_req(struct fc_lport *lport, struct fc_frame *fp)
{
	struct fc_seq_els_data els_data;

	/*
	 * Handle FLOGI, PLOGI and LOGO requests separately, since they
	 * don't require prior login.
	 * Check for unsupported opcodes first and reject them.
	 * For some ops, it would be incorrect to reject with "PLOGI required".
	 */
	switch (fc_frame_payload_op(fp)) {
	case ELS_FLOGI:
		fc_rport_recv_flogi_req(lport, fp);
		break;
	case ELS_PLOGI:
		fc_rport_recv_plogi_req(lport, fp);
		break;
	case ELS_LOGO:
		fc_rport_recv_logo_req(lport, fp);
		break;
	case ELS_PRLI:
	case ELS_PRLO:
	case ELS_ADISC:
	case ELS_RRQ:
	case ELS_REC:
	case ELS_RLS:
		fc_rport_recv_els_req(lport, fp);
		break;
	default:
		els_data.reason = ELS_RJT_UNSUP;
		els_data.explan = ELS_EXPL_NONE;
		lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &els_data);
		fc_frame_free(fp);
		break;
	}
}

/**
 * fc_rport_recv_plogi_req() - Handler for Port Login (PLOGI) requests
 * @lport: The local port that received the PLOGI request
 * @rx_fp: The PLOGI request frame
 *
 * Locking Note: The rport lock is held before calling this function.
 */
static void fc_rport_recv_plogi_req(struct fc_lport *lport,
				    struct fc_frame *rx_fp)
{
	struct fc_disc *disc;
	struct fc_rport_priv *rdata;
	struct fc_frame *fp = rx_fp;
	struct fc_els_flogi *pl;
	struct fc_seq_els_data rjt_data;
	u32 sid;

	sid = fc_frame_sid(fp);

	FC_RPORT_ID_DBG(lport, sid, "Received PLOGI request\n");

	pl = fc_frame_payload_get(fp, sizeof(*pl));
	if (!pl) {
		FC_RPORT_ID_DBG(lport, sid, "Received PLOGI too short\n");
		rjt_data.reason = ELS_RJT_PROT;
		rjt_data.explan = ELS_EXPL_INV_LEN;
		goto reject;
	}

	disc = &lport->disc;
	mutex_lock(&disc->disc_mutex);
	rdata = lport->tt.rport_create(lport, sid);
	if (!rdata) {
		mutex_unlock(&disc->disc_mutex);
		rjt_data.reason = ELS_RJT_UNAB;
		rjt_data.explan = ELS_EXPL_INSUF_RES;
		goto reject;
	}

	mutex_lock(&rdata->rp_mutex);
	mutex_unlock(&disc->disc_mutex);

	rdata->ids.port_name = get_unaligned_be64(&pl->fl_wwpn);
	rdata->ids.node_name = get_unaligned_be64(&pl->fl_wwnn);

	/*
	 * If the rport was just created, possibly due to the incoming PLOGI,
	 * set the state appropriately and accept the PLOGI.
	 *
	 * If we had also sent a PLOGI, and if the received PLOGI is from a
	 * higher WWPN, we accept it, otherwise an LS_RJT is sent with reason
	 * "command already in progress".
	 *
	 * XXX TBD: If the session was ready before, the PLOGI should result in
	 * all outstanding exchanges being reset.
	 */
	switch (rdata->rp_state) {
	case RPORT_ST_INIT:
		FC_RPORT_DBG(rdata, "Received PLOGI in INIT state\n");
		break;
	case RPORT_ST_PLOGI_WAIT:
		FC_RPORT_DBG(rdata, "Received PLOGI in PLOGI_WAIT state\n");
		break;
	case RPORT_ST_PLOGI:
		FC_RPORT_DBG(rdata, "Received PLOGI in PLOGI state\n");
		if (rdata->ids.port_name < lport->wwpn) {
			mutex_unlock(&rdata->rp_mutex);
			rjt_data.reason = ELS_RJT_INPROG;
			rjt_data.explan = ELS_EXPL_NONE;
			goto reject;
		}
		break;
	case RPORT_ST_PRLI:
	case RPORT_ST_RTV:
	case RPORT_ST_READY:
	case RPORT_ST_ADISC:
		FC_RPORT_DBG(rdata, "Received PLOGI in logged-in state %d "
			     "- ignored for now\n", rdata->rp_state);
		/* XXX TBD - should reset */
		break;
	case RPORT_ST_FLOGI:
	case RPORT_ST_DELETE:
		FC_RPORT_DBG(rdata, "Received PLOGI in state %s - send busy\n",
			     fc_rport_state(rdata));
		mutex_unlock(&rdata->rp_mutex);
		rjt_data.reason = ELS_RJT_BUSY;
		rjt_data.explan = ELS_EXPL_NONE;
		goto reject;
	}

	/*
	 * Get session payload size from incoming PLOGI.
	 */
	rdata->maxframe_size = fc_plogi_get_maxframe(pl, lport->mfs);

	/*
	 * Send LS_ACC.	 If this fails, the originator should retry.
	 */
	fp = fc_frame_alloc(lport, sizeof(*pl));
	if (!fp)
		goto out;

	fc_plogi_fill(lport, fp, ELS_LS_ACC);
	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);
	fc_rport_enter_prli(rdata);
out:
	mutex_unlock(&rdata->rp_mutex);
	fc_frame_free(rx_fp);
	return;

reject:
	lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &rjt_data);
	fc_frame_free(fp);
}

/**
 * fc_rport_recv_prli_req() - Handler for process login (PRLI) requests
 * @rdata: The remote port that sent the PRLI request
 * @rx_fp: The PRLI request frame
 *
 * Locking Note: The rport lock is exected to be held before calling
 * this function.
 */
static void fc_rport_recv_prli_req(struct fc_rport_priv *rdata,
				   struct fc_frame *rx_fp)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;
	struct {
		struct fc_els_prli prli;
		struct fc_els_spp spp;
	} *pp;
	struct fc_els_spp *rspp;	/* request service param page */
	struct fc_els_spp *spp;	/* response spp */
	unsigned int len;
	unsigned int plen;
	enum fc_els_spp_resp resp;
	struct fc_seq_els_data rjt_data;
	u32 fcp_parm;
	u32 roles = FC_RPORT_ROLE_UNKNOWN;

	FC_RPORT_DBG(rdata, "Received PRLI request while in state %s\n",
		     fc_rport_state(rdata));

	len = fr_len(rx_fp) - sizeof(struct fc_frame_header);
	pp = fc_frame_payload_get(rx_fp, sizeof(*pp));
	if (!pp)
		goto reject_len;
	plen = ntohs(pp->prli.prli_len);
	if ((plen % 4) != 0 || plen > len || plen < 16)
		goto reject_len;
	if (plen < len)
		len = plen;
	plen = pp->prli.prli_spp_len;
	if ((plen % 4) != 0 || plen < sizeof(*spp) ||
	    plen > len || len < sizeof(*pp) || plen < 12)
		goto reject_len;
	rspp = &pp->spp;

	fp = fc_frame_alloc(lport, len);
	if (!fp) {
		rjt_data.reason = ELS_RJT_UNAB;
		rjt_data.explan = ELS_EXPL_INSUF_RES;
		goto reject;
	}
	pp = fc_frame_payload_get(fp, len);
	WARN_ON(!pp);
	memset(pp, 0, len);
	pp->prli.prli_cmd = ELS_LS_ACC;
	pp->prli.prli_spp_len = plen;
	pp->prli.prli_len = htons(len);
	len -= sizeof(struct fc_els_prli);

	/* reinitialize remote port roles */
	rdata->ids.roles = FC_RPORT_ROLE_UNKNOWN;

	/*
	 * Go through all the service parameter pages and build
	 * response.  If plen indicates longer SPP than standard,
	 * use that.  The entire response has been pre-cleared above.
	 */
	spp = &pp->spp;
	while (len >= plen) {
		spp->spp_type = rspp->spp_type;
		spp->spp_type_ext = rspp->spp_type_ext;
		spp->spp_flags = rspp->spp_flags & FC_SPP_EST_IMG_PAIR;
		resp = FC_SPP_RESP_ACK;

		switch (rspp->spp_type) {
		case 0:	/* common to all FC-4 types */
			break;
		case FC_TYPE_FCP:
			fcp_parm = ntohl(rspp->spp_params);
			if (fcp_parm & FCP_SPPF_RETRY)
				rdata->flags |= FC_RP_FLAGS_RETRY;
			rdata->supported_classes = FC_COS_CLASS3;
			if (fcp_parm & FCP_SPPF_INIT_FCN)
				roles |= FC_RPORT_ROLE_FCP_INITIATOR;
			if (fcp_parm & FCP_SPPF_TARG_FCN)
				roles |= FC_RPORT_ROLE_FCP_TARGET;
			rdata->ids.roles = roles;

			spp->spp_params = htonl(lport->service_params);
			break;
		default:
			resp = FC_SPP_RESP_INVL;
			break;
		}
		spp->spp_flags |= resp;
		len -= plen;
		rspp = (struct fc_els_spp *)((char *)rspp + plen);
		spp = (struct fc_els_spp *)((char *)spp + plen);
	}

	/*
	 * Send LS_ACC.	 If this fails, the originator should retry.
	 */
	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);

	switch (rdata->rp_state) {
	case RPORT_ST_PRLI:
		fc_rport_enter_ready(rdata);
		break;
	default:
		break;
	}
	goto drop;

reject_len:
	rjt_data.reason = ELS_RJT_PROT;
	rjt_data.explan = ELS_EXPL_INV_LEN;
reject:
	lport->tt.seq_els_rsp_send(rx_fp, ELS_LS_RJT, &rjt_data);
drop:
	fc_frame_free(rx_fp);
}

/**
 * fc_rport_recv_prlo_req() - Handler for process logout (PRLO) requests
 * @rdata: The remote port that sent the PRLO request
 * @rx_fp: The PRLO request frame
 *
 * Locking Note: The rport lock is exected to be held before calling
 * this function.
 */
static void fc_rport_recv_prlo_req(struct fc_rport_priv *rdata,
				   struct fc_frame *rx_fp)
{
	struct fc_lport *lport = rdata->local_port;
	struct fc_frame *fp;
	struct {
		struct fc_els_prlo prlo;
		struct fc_els_spp spp;
	} *pp;
	struct fc_els_spp *rspp;	/* request service param page */
	struct fc_els_spp *spp;		/* response spp */
	unsigned int len;
	unsigned int plen;
	struct fc_seq_els_data rjt_data;

	FC_RPORT_DBG(rdata, "Received PRLO request while in state %s\n",
		     fc_rport_state(rdata));

	len = fr_len(rx_fp) - sizeof(struct fc_frame_header);
	pp = fc_frame_payload_get(rx_fp, sizeof(*pp));
	if (!pp)
		goto reject_len;
	plen = ntohs(pp->prlo.prlo_len);
	if (plen != 20)
		goto reject_len;
	if (plen < len)
		len = plen;

	rspp = &pp->spp;

	fp = fc_frame_alloc(lport, len);
	if (!fp) {
		rjt_data.reason = ELS_RJT_UNAB;
		rjt_data.explan = ELS_EXPL_INSUF_RES;
		goto reject;
	}

	pp = fc_frame_payload_get(fp, len);
	WARN_ON(!pp);
	memset(pp, 0, len);
	pp->prlo.prlo_cmd = ELS_LS_ACC;
	pp->prlo.prlo_obs = 0x10;
	pp->prlo.prlo_len = htons(len);
	spp = &pp->spp;
	spp->spp_type = rspp->spp_type;
	spp->spp_type_ext = rspp->spp_type_ext;
	spp->spp_flags = FC_SPP_RESP_ACK;

	fc_rport_enter_delete(rdata, RPORT_EV_LOGO);

	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
	lport->tt.frame_send(lport, fp);
	goto drop;

reject_len:
	rjt_data.reason = ELS_RJT_PROT;
	rjt_data.explan = ELS_EXPL_INV_LEN;
reject:
	lport->tt.seq_els_rsp_send(rx_fp, ELS_LS_RJT, &rjt_data);
drop:
	fc_frame_free(rx_fp);
}

/**
 * fc_rport_recv_logo_req() - Handler for logout (LOGO) requests
 * @lport: The local port that received the LOGO request
 * @fp:	   The LOGO request frame
 *
 * Locking Note: The rport lock is exected to be held before calling
 * this function.
 */
static void fc_rport_recv_logo_req(struct fc_lport *lport, struct fc_frame *fp)
{
	struct fc_rport_priv *rdata;
	u32 sid;

	lport->tt.seq_els_rsp_send(fp, ELS_LS_ACC, NULL);

	sid = fc_frame_sid(fp);

	mutex_lock(&lport->disc.disc_mutex);
	rdata = lport->tt.rport_lookup(lport, sid);
	if (rdata) {
		mutex_lock(&rdata->rp_mutex);
		FC_RPORT_DBG(rdata, "Received LOGO request while in state %s\n",
			     fc_rport_state(rdata));

		fc_rport_enter_delete(rdata, RPORT_EV_LOGO);
		mutex_unlock(&rdata->rp_mutex);
	} else
		FC_RPORT_ID_DBG(lport, sid,
				"Received LOGO from non-logged-in port\n");
	mutex_unlock(&lport->disc.disc_mutex);
	fc_frame_free(fp);
}

/**
 * fc_rport_flush_queue() - Flush the rport_event_queue
 */
static void fc_rport_flush_queue(void)
{
	flush_workqueue(rport_event_queue);
}

/**
 * fc_rport_init() - Initialize the remote port layer for a local port
 * @lport: The local port to initialize the remote port layer for
 */
int fc_rport_init(struct fc_lport *lport)
{
	if (!lport->tt.rport_lookup)
		lport->tt.rport_lookup = fc_rport_lookup;

	if (!lport->tt.rport_create)
		lport->tt.rport_create = fc_rport_create;

	if (!lport->tt.rport_login)
		lport->tt.rport_login = fc_rport_login;

	if (!lport->tt.rport_logoff)
		lport->tt.rport_logoff = fc_rport_logoff;

	if (!lport->tt.rport_recv_req)
		lport->tt.rport_recv_req = fc_rport_recv_req;

	if (!lport->tt.rport_flush_queue)
		lport->tt.rport_flush_queue = fc_rport_flush_queue;

	if (!lport->tt.rport_destroy)
		lport->tt.rport_destroy = fc_rport_destroy;

	return 0;
}
EXPORT_SYMBOL(fc_rport_init);

/**
 * fc_setup_rport() - Initialize the rport_event_queue
 */
int fc_setup_rport()
{
	rport_event_queue = create_singlethread_workqueue("fc_rport_eq");
	if (!rport_event_queue)
		return -ENOMEM;
	return 0;
}

/**
 * fc_destroy_rport() - Destroy the rport_event_queue
 */
void fc_destroy_rport()
{
	destroy_workqueue(rport_event_queue);
}

/**
 * fc_rport_terminate_io() - Stop all outstanding I/O on a remote port
 * @rport: The remote port whose I/O should be terminated
 */
void fc_rport_terminate_io(struct fc_rport *rport)
{
	struct fc_rport_libfc_priv *rpriv = rport->dd_data;
	struct fc_lport *lport = rpriv->local_port;

	lport->tt.exch_mgr_reset(lport, 0, rport->port_id);
	lport->tt.exch_mgr_reset(lport, rport->port_id, 0);
}
EXPORT_SYMBOL(fc_rport_terminate_io);