summaryrefslogtreecommitdiffstats
path: root/drivers/s390/net/iucv.c
blob: e08e74e16124704b1f7b8bede6092a2d1cab376e (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
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
/* 
 * $Id: iucv.c,v 1.45 2005/04/26 22:59:06 braunu Exp $
 *
 * IUCV network driver
 *
 * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation
 * Author(s):
 *    Original source:
 *      Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
 *      Xenia Tkatschow (xenia@us.ibm.com)
 *    2Gb awareness and general cleanup:
 *      Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
 *
 * Documentation used:
 *    The original source
 *    CP Programming Service, IBM document # SC24-5760
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * RELEASE-TAG: IUCV lowlevel driver $Revision: 1.45 $
 *
 */

/* #define DEBUG */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/config.h>

#include <linux/spinlock.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/device.h>
#include <asm/atomic.h>
#include "iucv.h"
#include <asm/io.h>
#include <asm/s390_ext.h>
#include <asm/ebcdic.h>
#include <asm/smp.h>
#include <asm/ccwdev.h> //for root device stuff

/* FLAGS:
 * All flags are defined in the field IPFLAGS1 of each function
 * and can be found in CP Programming Services.
 * IPSRCCLS - Indicates you have specified a source class
 * IPFGMCL  - Indicates you have specified a target class
 * IPFGPID  - Indicates you have specified a pathid
 * IPFGMID  - Indicates you have specified a message ID
 * IPANSLST - Indicates that you are using an address list for
 *            reply data
 * IPBUFLST - Indicates that you are using an address list for
 *            message data
 */

#define IPSRCCLS 	0x01
#define IPFGMCL         0x01
#define IPFGPID         0x02
#define IPFGMID         0x04
#define IPANSLST        0x08
#define IPBUFLST        0x40

static int
iucv_bus_match (struct device *dev, struct device_driver *drv)
{
	return 0;
}

struct bus_type iucv_bus = {
	.name = "iucv",
	.match = iucv_bus_match,
};	

struct device *iucv_root;

/* General IUCV interrupt structure */
typedef struct {
	__u16 ippathid;
	__u8  res1;
	__u8  iptype;
	__u32 res2;
	__u8  ipvmid[8];
	__u8  res3[24];
} iucv_GeneralInterrupt;

static iucv_GeneralInterrupt *iucv_external_int_buffer = NULL;

/* Spin Lock declaration */

static DEFINE_SPINLOCK(iucv_lock);

static int messagesDisabled = 0;

/***************INTERRUPT HANDLING ***************/

typedef struct {
	struct list_head queue;
	iucv_GeneralInterrupt data;
} iucv_irqdata;

static struct list_head  iucv_irq_queue;
static DEFINE_SPINLOCK(iucv_irq_queue_lock);

/*
 *Internal function prototypes
 */
static void iucv_tasklet_handler(unsigned long);
static void iucv_irq_handler(struct pt_regs *, __u16);

static DECLARE_TASKLET(iucv_tasklet,iucv_tasklet_handler,0);

/************ FUNCTION ID'S ****************************/

#define ACCEPT          10
#define CONNECT         11
#define DECLARE_BUFFER  12
#define PURGE           9
#define QUERY           0
#define QUIESCE         13
#define RECEIVE         5
#define REJECT          8
#define REPLY           6
#define RESUME          14
#define RETRIEVE_BUFFER 2
#define SEND            4
#define SETMASK         16
#define SEVER           15

/**
 * Structure: handler
 * members: list - list management.
 *          structure: id
 *             userid - 8 char array of machine identification
 *             user_data - 16 char array for user identification
 *             mask - 24 char array used to compare the 2 previous
 *          interrupt_table - vector of interrupt functions.
 *          pgm_data -  ulong, application data that is passed
 *                      to the interrupt handlers
*/
typedef struct handler_t {
	struct list_head list;
	struct {
		__u8 userid[8];
		__u8 user_data[16];
		__u8 mask[24];
	}                    id;
	iucv_interrupt_ops_t *interrupt_table;
	void                 *pgm_data;
} handler;

/**
 * iucv_handler_table: List of registered handlers.
 */
static struct list_head iucv_handler_table;

/**
 * iucv_pathid_table: an array of *handler pointing into
 *                    iucv_handler_table for fast indexing by pathid;
 */
static handler **iucv_pathid_table;

static unsigned long max_connections;

/**
 * iucv_cpuid: contains the logical cpu number of the cpu which
 * has declared the iucv buffer by issuing DECLARE_BUFFER.
 * If no cpu has done the initialization iucv_cpuid contains -1.
 */
static int iucv_cpuid = -1;
/**
 * register_flag: is 0 when external interrupt has not been registered
 */
static int register_flag;

/****************FIVE 40-BYTE PARAMETER STRUCTURES******************/
/* Data struct 1: iparml_control
 * Used for iucv_accept
 *          iucv_connect
 *          iucv_quiesce
 *          iucv_resume
 *          iucv_sever
 *          iucv_retrieve_buffer
 * Data struct 2: iparml_dpl     (data in parameter list)
 * Used for iucv_send_prmmsg
 *          iucv_send2way_prmmsg
 *          iucv_send2way_prmmsg_array
 *          iucv_reply_prmmsg
 * Data struct 3: iparml_db       (data in a buffer)
 * Used for iucv_receive
 *          iucv_receive_array
 *          iucv_reject
 *          iucv_reply
 *          iucv_reply_array
 *          iucv_send
 *          iucv_send_array
 *          iucv_send2way
 *          iucv_send2way_array
 *          iucv_declare_buffer
 * Data struct 4: iparml_purge
 * Used for iucv_purge
 *          iucv_query
 * Data struct 5: iparml_set_mask
 * Used for iucv_set_mask
 */

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u16 ipmsglim;
	__u16 res1;
	__u8  ipvmid[8];
	__u8  ipuser[16];
	__u8  iptarget[8];
} iparml_control;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u32 iptrgcls;
	__u8  iprmmsg[8];
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 ipbfadr2;
	__u32 ipbfln2f;
	__u32 res;
} iparml_dpl;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u32 iptrgcls;
	__u32 ipbfadr1;
	__u32 ipbfln1f;
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 ipbfadr2;
	__u32 ipbfln2f;
	__u32 res;
} iparml_db;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u8  ipaudit[3];
	__u8  res1[5];
	__u32 res2;
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 res3[3];
} iparml_purge;

typedef struct {
	__u8  ipmask;
	__u8  res1[2];
	__u8  iprcode;
	__u32 res2[9];
} iparml_set_mask;

typedef struct {
	union {
		iparml_control  p_ctrl;
		iparml_dpl      p_dpl;
		iparml_db       p_db;
		iparml_purge    p_purge;
		iparml_set_mask p_set_mask;
	} param;
	atomic_t in_use;
	__u32    res;
}  __attribute__ ((aligned(8))) iucv_param;
#define PARAM_POOL_SIZE (PAGE_SIZE / sizeof(iucv_param))

static iucv_param * iucv_param_pool;

MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
MODULE_LICENSE("GPL");

/*
 * Debugging stuff
 *******************************************************************************/


#ifdef DEBUG
static int debuglevel = 0;

module_param(debuglevel, int, 0);
MODULE_PARM_DESC(debuglevel,
 "Specifies the debug level (0=off ... 3=all)");

static void
iucv_dumpit(char *title, void *buf, int len)
{
	int i;
	__u8 *p = (__u8 *)buf;

	if (debuglevel < 3)
		return;

	printk(KERN_DEBUG "%s\n", title);
	printk("  ");
	for (i = 0; i < len; i++) {
		if (!(i % 16) && i != 0)
			printk ("\n  ");
		else if (!(i % 4) && i != 0)
			printk(" ");
		printk("%02X", *p++);
	}
	if (len % 16)
		printk ("\n");
	return;
}
#define iucv_debug(lvl, fmt, args...) \
do { \
	if (debuglevel >= lvl) \
		printk(KERN_DEBUG "%s: " fmt "\n", __FUNCTION__ , ## args); \
} while (0)

#else

#define iucv_debug(lvl, fmt, args...)
#define iucv_dumpit(title, buf, len)

#endif

/*
 * Internal functions
 *******************************************************************************/

/**
 * print start banner
 */
static void
iucv_banner(void)
{
	char vbuf[] = "$Revision: 1.45 $";
	char *version = vbuf;

	if ((version = strchr(version, ':'))) {
		char *p = strchr(version + 1, '$');
		if (p)
			*p = '\0';
	} else
		version = " ??? ";
	printk(KERN_INFO
	       "IUCV lowlevel driver Version%s initialized\n", version);
}

/**
 * iucv_init - Initialization
 *
 * Allocates and initializes various data structures.
 */
static int
iucv_init(void)
{
	int ret;

	if (iucv_external_int_buffer)
		return 0;

	if (!MACHINE_IS_VM) {
		printk(KERN_ERR "IUCV: IUCV connection needs VM as base\n");
		return -EPROTONOSUPPORT;
	}

	ret = bus_register(&iucv_bus);
	if (ret) {
		printk(KERN_ERR "IUCV: failed to register bus.\n");
		return ret;
	}

	iucv_root = s390_root_dev_register("iucv");
	if (IS_ERR(iucv_root)) {
		printk(KERN_ERR "IUCV: failed to register iucv root.\n");
		bus_unregister(&iucv_bus);
		return PTR_ERR(iucv_root);
	}

	/* Note: GFP_DMA used used to get memory below 2G */
	iucv_external_int_buffer = kmalloc(sizeof(iucv_GeneralInterrupt),
					   GFP_KERNEL|GFP_DMA);
	if (!iucv_external_int_buffer) {
		printk(KERN_WARNING
		       "%s: Could not allocate external interrupt buffer\n",
		       __FUNCTION__);
		s390_root_dev_unregister(iucv_root);
		bus_unregister(&iucv_bus);
		return -ENOMEM;
	}
	memset(iucv_external_int_buffer, 0, sizeof(iucv_GeneralInterrupt));

	/* Initialize parameter pool */
	iucv_param_pool = kmalloc(sizeof(iucv_param) * PARAM_POOL_SIZE,
				  GFP_KERNEL|GFP_DMA);
	if (!iucv_param_pool) {
		printk(KERN_WARNING "%s: Could not allocate param pool\n",
		       __FUNCTION__);
		kfree(iucv_external_int_buffer);
		iucv_external_int_buffer = NULL;
		s390_root_dev_unregister(iucv_root);
		bus_unregister(&iucv_bus);
		return -ENOMEM;
	}
	memset(iucv_param_pool, 0, sizeof(iucv_param) * PARAM_POOL_SIZE);

	/* Initialize irq queue */
	INIT_LIST_HEAD(&iucv_irq_queue);

	/* Initialize handler table */
	INIT_LIST_HEAD(&iucv_handler_table);

	iucv_banner();
	return 0;
}

/**
 * iucv_exit - De-Initialization
 *
 * Frees everything allocated from iucv_init.
 */
static int iucv_retrieve_buffer (void);

static void
iucv_exit(void)
{
	iucv_retrieve_buffer();
      	if (iucv_external_int_buffer) {
		kfree(iucv_external_int_buffer);
		iucv_external_int_buffer = NULL;
	}
	if (iucv_param_pool) {
		kfree(iucv_param_pool);
		iucv_param_pool = NULL;
	}
	s390_root_dev_unregister(iucv_root);
	bus_unregister(&iucv_bus);
	printk(KERN_INFO "IUCV lowlevel driver unloaded\n");
}

/**
 * grab_param: - Get a parameter buffer from the pre-allocated pool.
 *
 * This function searches for an unused element in the pre-allocated pool
 * of parameter buffers. If one is found, it marks it "in use" and returns
 * a pointer to it. The calling function is responsible for releasing it
 * when it has finished its usage.
 *
 * Returns: A pointer to iucv_param.
 */
static __inline__ iucv_param *
grab_param(void)
{
	iucv_param *ptr;
        static int hint = 0;

	ptr = iucv_param_pool + hint;
	do {
		ptr++;
		if (ptr >= iucv_param_pool + PARAM_POOL_SIZE)
			ptr = iucv_param_pool;
	} while (atomic_compare_and_swap(0, 1, &ptr->in_use));
	hint = ptr - iucv_param_pool;

	memset(&ptr->param, 0, sizeof(ptr->param));
	return ptr;
}

/**
 * release_param - Release a parameter buffer.
 * @p: A pointer to a struct iucv_param, previously obtained by calling
 *     grab_param().
 *
 * This function marks the specified parameter buffer "unused".
 */
static __inline__ void
release_param(void *p)
{
	atomic_set(&((iucv_param *)p)->in_use, 0);
}

/**
 * iucv_add_handler: - Add a new handler
 * @new_handler: handle that is being entered into chain.
 *
 * Places new handle on iucv_handler_table, if identical handler is not
 * found.
 *
 * Returns: 0 on success, !0 on failure (handler already in chain).
 */
static int
iucv_add_handler (handler *new)
{
	ulong flags;

	iucv_debug(1, "entering");
	iucv_dumpit("handler:", new, sizeof(handler));

	spin_lock_irqsave (&iucv_lock, flags);
	if (!list_empty(&iucv_handler_table)) {
		struct list_head *lh;

		/**
		 * Search list for handler with identical id. If one
		 * is found, the new handler is _not_ added.
		 */
		list_for_each(lh, &iucv_handler_table) {
			handler *h = list_entry(lh, handler, list);
			if (!memcmp(&new->id, &h->id, sizeof(h->id))) {
				iucv_debug(1, "ret 1");
				spin_unlock_irqrestore (&iucv_lock, flags);
				return 1;
			}
		}
	}
	/**
	 * If we get here, no handler was found.
	 */
	INIT_LIST_HEAD(&new->list);
	list_add(&new->list, &iucv_handler_table);
	spin_unlock_irqrestore (&iucv_lock, flags);

	iucv_debug(1, "exiting");
	return 0;
}

/**
 * b2f0:
 * @code: identifier of IUCV call to CP.
 * @parm: pointer to 40 byte iparml area passed to CP
 *
 * Calls CP to execute IUCV commands.
 *
 * Returns: return code from CP's IUCV call
 */
static __inline__ ulong
b2f0(__u32 code, void *parm)
{
	iucv_dumpit("iparml before b2f0 call:", parm, sizeof(iucv_param));

	asm volatile (
		"LRA   1,0(%1)\n\t"
		"LR    0,%0\n\t"
		".long 0xb2f01000"
		:
		: "d" (code), "a" (parm)
		: "0", "1"
		);

	iucv_dumpit("iparml after b2f0 call:", parm, sizeof(iucv_param));

	return (unsigned long)*((__u8 *)(parm + 3));
}

/*
 * Name: iucv_add_pathid
 * Purpose: Adds a path id to the system.
 * Input: pathid -  pathid that is going to be entered into system
 *        handle -  address of handler that the pathid will be associated
 *		   with.
 *        pgm_data - token passed in by application.
 * Output: 0: successful addition of pathid
 *	   - EINVAL - pathid entry is being used by another application
 *	   - ENOMEM - storage allocation for a new pathid table failed
*/
static int
__iucv_add_pathid(__u16 pathid, handler *handler)
{

	iucv_debug(1, "entering");

	iucv_debug(1, "handler is pointing to %p", handler);

	if (pathid > (max_connections - 1))
		return -EINVAL;

	if (iucv_pathid_table[pathid]) {
		iucv_debug(1, "pathid entry is %p", iucv_pathid_table[pathid]);
		printk(KERN_WARNING
		       "%s: Pathid being used, error.\n", __FUNCTION__);
		return -EINVAL;
	}
	iucv_pathid_table[pathid] = handler;

	iucv_debug(1, "exiting");
	return 0;
}				/* end of add_pathid function */

static int
iucv_add_pathid(__u16 pathid, handler *handler)
{
	ulong flags;
	int rc;

	spin_lock_irqsave (&iucv_lock, flags);
	rc = __iucv_add_pathid(pathid, handler);
	spin_unlock_irqrestore (&iucv_lock, flags);
	return rc;
}

static void
iucv_remove_pathid(__u16 pathid)
{
	ulong flags;

	if (pathid > (max_connections - 1))
		return;

	spin_lock_irqsave (&iucv_lock, flags);
	iucv_pathid_table[pathid] = NULL;
	spin_unlock_irqrestore (&iucv_lock, flags);
}

/**
 * iucv_declare_buffer_cpuid
 * Register at VM for subsequent IUCV operations. This is executed
 * on the reserved CPU iucv_cpuid. Called from iucv_declare_buffer().
 */
static void
iucv_declare_buffer_cpuid (void *result)
{
	iparml_db *parm;

	parm = (iparml_db *)grab_param();
	parm->ipbfadr1 = virt_to_phys(iucv_external_int_buffer);
	if ((*((ulong *)result) = b2f0(DECLARE_BUFFER, parm)) == 1)
		*((ulong *)result) = parm->iprcode;
	release_param(parm);
}

/**
 * iucv_retrieve_buffer_cpuid:
 * Unregister IUCV usage at VM. This is always executed on the same
 * cpu that registered the buffer to VM.
 * Called from iucv_retrieve_buffer().
 */
static void
iucv_retrieve_buffer_cpuid (void *cpu)
{
	iparml_control *parm;

	parm = (iparml_control *)grab_param();
	b2f0(RETRIEVE_BUFFER, parm);
	release_param(parm);
}

/**
 * Name: iucv_declare_buffer
 * Purpose: Specifies the guests real address of an external
 *          interrupt.
 * Input: void
 * Output: iprcode - return code from b2f0 call
 */
static int
iucv_declare_buffer (void)
{
	unsigned long flags;
	ulong b2f0_result;

	iucv_debug(1, "entering");
	b2f0_result = -ENODEV;
	spin_lock_irqsave (&iucv_lock, flags);
	if (iucv_cpuid == -1) {
		/* Reserve any cpu for use by iucv. */
		iucv_cpuid = smp_get_cpu(CPU_MASK_ALL);
		spin_unlock_irqrestore (&iucv_lock, flags);
		smp_call_function_on(iucv_declare_buffer_cpuid,
			&b2f0_result, 0, 1, iucv_cpuid);
		if (b2f0_result) {
			smp_put_cpu(iucv_cpuid);
			iucv_cpuid = -1;
		}
		iucv_debug(1, "Address of EIB = %p", iucv_external_int_buffer);
	} else {
		spin_unlock_irqrestore (&iucv_lock, flags);
		b2f0_result = 0;
	}
	iucv_debug(1, "exiting");
	return b2f0_result;
}

/**
 * iucv_retrieve_buffer:
 *
 * Terminates all use of IUCV.
 * Returns: return code from CP
 */
static int
iucv_retrieve_buffer (void)
{
	iucv_debug(1, "entering");
	if (iucv_cpuid != -1) {
		smp_call_function_on(iucv_retrieve_buffer_cpuid,
				     0, 0, 1, iucv_cpuid);
		/* Release the cpu reserved by iucv_declare_buffer. */
		smp_put_cpu(iucv_cpuid);
		iucv_cpuid = -1;
	}
	iucv_debug(1, "exiting");
	return 0;
}

/**
 * iucv_remove_handler:
 * @users_handler: handler to be removed
 *
 * Remove handler when application unregisters.
 */
static void
iucv_remove_handler(handler *handler)
{
	unsigned long flags;

	if ((!iucv_pathid_table) || (!handler))
		return;

	iucv_debug(1, "entering");

	spin_lock_irqsave (&iucv_lock, flags);
	list_del(&handler->list);
	if (list_empty(&iucv_handler_table)) {
		if (register_flag) {
			unregister_external_interrupt(0x4000, iucv_irq_handler);
			register_flag = 0;
		}
	}
	spin_unlock_irqrestore (&iucv_lock, flags);

	iucv_debug(1, "exiting");
	return;
}

/**
 * iucv_register_program:
 * @pgmname:  user identification
 * @userid:   machine identification
 * @pgmmask:  Indicates which bits in the pgmname and userid combined will be
 *            used to determine who is given control.
 * @ops:      Address of interrupt handler table.
 * @pgm_data: Application data to be passed to interrupt handlers.
 *
 * Registers an application with IUCV.
 * Returns:
 *           The address of handler, or NULL on failure.
 * NOTE on pgmmask:
 *   If pgmname, userid and pgmmask are provided, pgmmask is entered into the
 *   handler as is.
 *   If pgmmask is NULL, the internal mask is set to all 0xff's
 *   When userid is NULL, the first 8 bytes of the internal mask are forced
 *   to 0x00.
 *   If pgmmask and userid are NULL, the first 8 bytes of the internal mask
 *   are forced to 0x00 and the last 16 bytes to 0xff.
 */

iucv_handle_t
iucv_register_program (__u8 pgmname[16],
		       __u8 userid[8],
		       __u8 pgmmask[24],
		       iucv_interrupt_ops_t * ops, void *pgm_data)
{
	ulong rc = 0;		/* return code from function calls */
	handler *new_handler;

	iucv_debug(1, "entering");

	if (ops == NULL) {
		/* interrupt table is not defined */
		printk(KERN_WARNING "%s: Interrupt table is not defined, "
		       "exiting\n", __FUNCTION__);
		return NULL;
	}
	if (!pgmname) {
		printk(KERN_WARNING "%s: pgmname not provided\n", __FUNCTION__);
		return NULL;
	}

	/* Allocate handler entry */
	new_handler = (handler *)kmalloc(sizeof(handler), GFP_ATOMIC);
	if (new_handler == NULL) {
		printk(KERN_WARNING "%s: storage allocation for new handler "
		       "failed.\n", __FUNCTION__);
		return NULL;
	}

	if (!iucv_pathid_table) {
		if (iucv_init()) {
			kfree(new_handler);
			return NULL;
		}

		max_connections = iucv_query_maxconn();
		iucv_pathid_table = kmalloc(max_connections * sizeof(handler *),
				       GFP_ATOMIC);
		if (iucv_pathid_table == NULL) {
			printk(KERN_WARNING "%s: iucv_pathid_table storage "
			       "allocation failed\n", __FUNCTION__);
			kfree(new_handler);
			return NULL;
		}
		memset (iucv_pathid_table, 0, max_connections * sizeof(handler *));
	}
	memset(new_handler, 0, sizeof (handler));
	memcpy(new_handler->id.user_data, pgmname,
		sizeof (new_handler->id.user_data));
	if (userid) {
		memcpy (new_handler->id.userid, userid,
			sizeof (new_handler->id.userid));
		ASCEBC (new_handler->id.userid,
			sizeof (new_handler->id.userid));
		EBC_TOUPPER (new_handler->id.userid,
			     sizeof (new_handler->id.userid));
		
		if (pgmmask) {
			memcpy (new_handler->id.mask, pgmmask,
				sizeof (new_handler->id.mask));
		} else {
			memset (new_handler->id.mask, 0xFF,
				sizeof (new_handler->id.mask));
		}
	} else {
		if (pgmmask) {
			memcpy (new_handler->id.mask, pgmmask,
				sizeof (new_handler->id.mask));
		} else {
			memset (new_handler->id.mask, 0xFF,
				sizeof (new_handler->id.mask));
		}
		memset (new_handler->id.userid, 0x00,
			sizeof (new_handler->id.userid));
	}
	/* fill in the rest of handler */
	new_handler->pgm_data = pgm_data;
	new_handler->interrupt_table = ops;

	/*
	 * Check if someone else is registered with same pgmname, userid
	 * and mask. If someone is already registered with same pgmname,
	 * userid and mask, registration will fail and NULL will be returned
	 * to the application.
	 * If identical handler not found, then handler is added to list.
	 */
	rc = iucv_add_handler(new_handler);
	if (rc) {
		printk(KERN_WARNING "%s: Someone already registered with same "
		       "pgmname, userid, pgmmask\n", __FUNCTION__);
		kfree (new_handler);
		return NULL;
	}

	rc = iucv_declare_buffer();
	if (rc) {
		char *err = "Unknown";
		iucv_remove_handler(new_handler);
		kfree(new_handler);
		switch(rc) {
		case 0x03:
			err = "Directory error";
			break;
		case 0x0a:
			err = "Invalid length";
			break;
		case 0x13:
			err = "Buffer already exists";
			break;
		case 0x3e:
			err = "Buffer overlap";
			break;
		case 0x5c:
			err = "Paging or storage error";
			break;
		}
		printk(KERN_WARNING "%s: iucv_declare_buffer "
		       "returned error 0x%02lx (%s)\n", __FUNCTION__, rc, err);
		return NULL;
	}
	if (!register_flag) {
		/* request the 0x4000 external interrupt */
		rc = register_external_interrupt (0x4000, iucv_irq_handler);
		if (rc) {
			iucv_remove_handler(new_handler);
			kfree (new_handler);
			printk(KERN_WARNING "%s: "
			       "register_external_interrupt returned %ld\n",
			       __FUNCTION__, rc);
			return NULL;

		}
		register_flag = 1;
	}
	iucv_debug(1, "exiting");
	return new_handler;
}				/* end of register function */

/**
 * iucv_unregister_program:
 * @handle: address of handler
 *
 * Unregister application with IUCV.
 * Returns:
 *   0 on success, -EINVAL, if specified handle is invalid.
 */

int
iucv_unregister_program (iucv_handle_t handle)
{
	handler *h = NULL;
	struct list_head *lh;
	int i;
	ulong flags;

	iucv_debug(1, "entering");
	iucv_debug(1, "address of handler is %p", h);

	/* Checking if handle is valid  */
	spin_lock_irqsave (&iucv_lock, flags);
	list_for_each(lh, &iucv_handler_table) {
		if ((handler *)handle == list_entry(lh, handler, list)) {
			h = (handler *)handle;
			break;
		}
	}
	if (!h) {
		spin_unlock_irqrestore (&iucv_lock, flags);
		if (handle)
			printk(KERN_WARNING
			       "%s: Handler not found in iucv_handler_table.\n",
			       __FUNCTION__);
		else
			printk(KERN_WARNING
			       "%s: NULL handle passed by application.\n",
			       __FUNCTION__);
		return -EINVAL;
	}

	/**
	 * First, walk thru iucv_pathid_table and sever any pathid which is
	 * still pointing to the handler to be removed.
	 */
	for (i = 0; i < max_connections; i++)
		if (iucv_pathid_table[i] == h) {
			spin_unlock_irqrestore (&iucv_lock, flags);
			iucv_sever(i, h->id.user_data);
			spin_lock_irqsave(&iucv_lock, flags);
		}
	spin_unlock_irqrestore (&iucv_lock, flags);

	iucv_remove_handler(h);
	kfree(h);

	iucv_debug(1, "exiting");
	return 0;
}

/**
 * iucv_accept:
 * @pathid:             Path identification number
 * @msglim_reqstd:      The number of outstanding messages requested.
 * @user_data:          Data specified by the iucv_connect function.
 * @flags1:             Contains options for this path.
 *     - IPPRTY (0x20)   Specifies if you want to send priority message.
 *     - IPRMDATA (0x80) Specifies whether your program can handle a message
 *                       in the parameter list.
 *     - IPQUSCE (0x40)  Specifies whether you want to quiesce the path being
 *		         established.
 * @handle:             Address of handler.
 * @pgm_data:           Application data passed to interrupt handlers.
 * @flags1_out:         Pointer to an int. If not NULL, on return the options for
 *                      the path are stored at the given location:
 *     - IPPRTY (0x20)  Indicates you may send a priority message.
 * @msglim:             Pointer to an __u16. If not NULL, on return the maximum
 *                      number of outstanding messages is stored at the given
 *                      location.
 *
 * This function is issued after the user receives a Connection Pending external
 * interrupt and now wishes to complete the IUCV communication path.
 * Returns:
 *   return code from CP
 */
int
iucv_accept(__u16 pathid, __u16 msglim_reqstd,
	     __u8 user_data[16], int flags1,
	     iucv_handle_t handle, void *pgm_data,
	     int *flags1_out, __u16 * msglim)
{
	ulong b2f0_result = 0;
	ulong flags;
	struct list_head *lh;
	handler *h = NULL;
	iparml_control *parm;

	iucv_debug(1, "entering");
	iucv_debug(1, "pathid = %d", pathid);

	/* Checking if handle is valid  */
	spin_lock_irqsave (&iucv_lock, flags);
	list_for_each(lh, &iucv_handler_table) {
		if ((handler *)handle == list_entry(lh, handler, list)) {
			h = (handler *)handle;
			break;
		}
	}
	spin_unlock_irqrestore (&iucv_lock, flags);

	if (!h) {
		if (handle)
			printk(KERN_WARNING
			       "%s: Handler not found in iucv_handler_table.\n",
			       __FUNCTION__);
		else
			printk(KERN_WARNING
			       "%s: NULL handle passed by application.\n",
			       __FUNCTION__);
		return -EINVAL;
	}

	parm = (iparml_control *)grab_param();

	parm->ippathid = pathid;
	parm->ipmsglim = msglim_reqstd;
	if (user_data)
		memcpy(parm->ipuser, user_data, sizeof(parm->ipuser));

	parm->ipflags1 = (__u8)flags1;
	b2f0_result = b2f0(ACCEPT, parm);

	if (!b2f0_result) {
		if (msglim)
			*msglim = parm->ipmsglim;
		if (pgm_data)
			h->pgm_data = pgm_data;
		if (flags1_out)
			*flags1_out = (parm->ipflags1 & IPPRTY) ? IPPRTY : 0;
	}
	release_param(parm);

	iucv_debug(1, "exiting");
	return b2f0_result;
}

/**
 * iucv_connect:
 * @pathid:        Path identification number
 * @msglim_reqstd: Number of outstanding messages requested
 * @user_data:     16-byte user data
 * @userid:        8-byte of user identification
 * @system_name:   8-byte identifying the system name
 * @flags1:        Specifies options for this path:
 *     - IPPRTY (0x20)   Specifies if you want to send priority message.
 *     - IPRMDATA (0x80) Specifies whether your program can handle a message
 *                       in  the parameter list.
 *     - IPQUSCE (0x40)  Specifies whether you want to quiesce the path being
 *                       established.
 *     - IPLOCAL (0x01)  Allows an application to force the partner to be on the
 *                       local system. If local is specified then target class
 *                       cannot be specified.
 * @flags1_out:    Pointer to an int. If not NULL, on return the options for
 *                 the path are stored at the given location:
 *     - IPPRTY (0x20)   Indicates you may send a priority message.
 * @msglim:        Pointer to an __u16. If not NULL, on return the maximum
 *                 number of outstanding messages is stored at the given
 *                 location.
 * @handle:        Address of handler.
 * @pgm_data:      Application data to be passed to interrupt handlers.
 *
 * This function establishes an IUCV path. Although the connect may complete
 * successfully, you are not able to use the path until you receive an IUCV
 * Connection Complete external interrupt.
 * Returns: return code from CP, or one of the following
 *     - ENOMEM
 *     - return code from iucv_declare_buffer
 *     - EINVAL - invalid handle passed by application
 *     - EINVAL - pathid address is NULL
 *     - ENOMEM - pathid table storage allocation failed
 *     - return code from internal function add_pathid
 */
int
iucv_connect (__u16 *pathid, __u16 msglim_reqstd,
	      __u8 user_data[16], __u8 userid[8],
	      __u8 system_name[8], int flags1,
	      int *flags1_out, __u16 * msglim,
	      iucv_handle_t handle, void *pgm_data)
{
	iparml_control *parm;
	iparml_control local_parm;
	struct list_head *lh;
	ulong b2f0_result = 0;
	ulong flags;
	int add_pathid_result = 0;
	handler *h = NULL;
	__u8 no_memory[16] = "NO MEMORY";

	iucv_debug(1, "entering");

	/* Checking if handle is valid  */
	spin_lock_irqsave (&iucv_lock, flags);
	list_for_each(lh, &iucv_handler_table) {
		if ((handler *)handle == list_entry(lh, handler, list)) {
			h = (handler *)handle;
			break;
		}
	}
	spin_unlock_irqrestore (&iucv_lock, flags);

	if (!h) {
		if (handle)
			printk(KERN_WARNING
			       "%s: Handler not found in iucv_handler_table.\n",
			       __FUNCTION__);
		else
			printk(KERN_WARNING
			       "%s: NULL handle passed by application.\n",
			       __FUNCTION__);
		return -EINVAL;
	}

	if (pathid == NULL) {
		printk(KERN_WARNING "%s: NULL pathid pointer\n",
		       __FUNCTION__);
		return -EINVAL;
	}

	parm = (iparml_control *)grab_param();

	parm->ipmsglim = msglim_reqstd;

	if (user_data)
		memcpy(parm->ipuser, user_data, sizeof(parm->ipuser));

	if (userid) {
		memcpy(parm->ipvmid, userid, sizeof(parm->ipvmid));
		ASCEBC(parm->ipvmid, sizeof(parm->ipvmid));
		EBC_TOUPPER(parm->ipvmid, sizeof(parm->ipvmid));
	}

	if (system_name) {
		memcpy(parm->iptarget, system_name, sizeof(parm->iptarget));
		ASCEBC(parm->iptarget, sizeof(parm->iptarget));
		EBC_TOUPPER(parm->iptarget, sizeof(parm->iptarget));
	}

	/* In order to establish an IUCV connection, the procedure is:
         *
         * b2f0(CONNECT)
         * take the ippathid from the b2f0 call
         * register the handler to the ippathid
         *
         * Unfortunately, the ConnectionEstablished message gets sent after the
         * b2f0(CONNECT) call but before the register is handled.
         *
         * In order for this race condition to be eliminated, the IUCV Control
         * Interrupts must be disabled for the above procedure.
         *
         * David Kennedy <dkennedy@linuxcare.com>
         */

	/* Enable everything but IUCV Control messages */
	iucv_setmask(~(AllInterrupts));
	messagesDisabled = 1;

	spin_lock_irqsave (&iucv_lock, flags);
	parm->ipflags1 = (__u8)flags1;
	b2f0_result = b2f0(CONNECT, parm);
	memcpy(&local_parm, parm, sizeof(local_parm));
	release_param(parm);
	parm = &local_parm;
	if (!b2f0_result)
		add_pathid_result = __iucv_add_pathid(parm->ippathid, h);
	spin_unlock_irqrestore (&iucv_lock, flags);

	if (b2f0_result) {
		iucv_setmask(~0);
		messagesDisabled = 0;
		return b2f0_result;
	}

	*pathid = parm->ippathid;

	/* Enable everything again */
	iucv_setmask(IUCVControlInterruptsFlag);

	if (msglim)
		*msglim = parm->ipmsglim;
	if (flags1_out)
		*flags1_out = (parm->ipflags1 & IPPRTY) ? IPPRTY : 0;

	if (add_pathid_result) {
		iucv_sever(*pathid, no_memory);
		printk(KERN_WARNING "%s: add_pathid failed with rc ="
			" %d\n", __FUNCTION__, add_pathid_result);
		return(add_pathid_result);
	}

	iucv_debug(1, "exiting");
	return b2f0_result;
}

/**
 * iucv_purge:
 * @pathid: Path identification number
 * @msgid:  Message ID of message to purge.
 * @srccls: Message class of the message to purge.
 * @audit:  Pointer to an __u32. If not NULL, on return, information about
 *          asynchronous errors that may have affected the normal completion
 *          of this message ist stored at the given location.
 *
 * Cancels a message you have sent.
 * Returns: return code from CP
 */
int
iucv_purge (__u16 pathid, __u32 msgid, __u32 srccls, __u32 *audit)
{
	iparml_purge *parm;
	ulong b2f0_result = 0;

	iucv_debug(1, "entering");
	iucv_debug(1, "pathid = %d", pathid);

	parm = (iparml_purge *)grab_param();

	parm->ipmsgid = msgid;
	parm->ippathid = pathid;
	parm->ipsrccls = srccls;
	parm->ipflags1 |= (IPSRCCLS | IPFGMID | IPFGPID);
	b2f0_result = b2f0(PURGE, parm);

	if (!b2f0_result && audit) {
		memcpy(audit, parm->ipaudit, sizeof(parm->ipaudit));
		/* parm->ipaudit has only 3 bytes */
		*audit >>= 8;
	}
	
	release_param(parm);

	iucv_debug(1, "b2f0_result = %ld", b2f0_result);
	iucv_debug(1, "exiting");
	return b2f0_result;
}

/**
 * iucv_query_generic:
 * @want_maxconn: Flag, describing which value is to be returned.
 *
 * Helper function for iucv_query_maxconn() and iucv_query_bufsize().
 *
 * Returns: The buffersize, if want_maxconn is 0; the maximum number of
 *           connections, if want_maxconn is 1 or an error-code < 0 on failure.
 */
static int
iucv_query_generic(int want_maxconn)
{
	iparml_purge *parm = (iparml_purge *)grab_param();
	int bufsize, maxconn;
	int ccode;

	/**
	 * Call b2f0 and store R0 (max buffer size),
	 * R1 (max connections) and CC.
	 */
	asm volatile (
		"LRA   1,0(%4)\n\t"
		"LR    0,%3\n\t"
		".long 0xb2f01000\n\t"
		"IPM   %0\n\t"
		"SRL   %0,28\n\t"
		"ST    0,%1\n\t"
		"ST    1,%2\n\t"
		: "=d" (ccode), "=m" (bufsize), "=m" (maxconn)
		: "d" (QUERY), "a" (parm)
		: "0", "1", "cc"
		);
	release_param(parm);

	if (ccode)
		return -EPERM;
	if (want_maxconn)
		return maxconn;
	return bufsize;
}

/**
 * iucv_query_maxconn:
 *
 * Determines the maximum number of connections thay may be established.
 *
 * Returns: Maximum number of connections that can be.
 */
ulong
iucv_query_maxconn(void)
{
	return iucv_query_generic(1);
}

/**
 * iucv_query_bufsize:
 *
 * Determines the size of the external interrupt buffer.
 *
 * Returns: Size of external interrupt buffer.
 */
ulong
iucv_query_bufsize (void)
{
	return iucv_query_generic(0);
}

/**
 * iucv_quiesce:
 * @pathid:    Path identification number
 * @user_data: 16-byte user data
 *
 * Temporarily suspends incoming messages on an IUCV path.
 * You can later reactivate the path by invoking the iucv_resume function.
 * Returns: return code from CP
 */
int
iucv_quiesce (__u16 pathid, __u8 user_data[16])
{
	iparml_control *parm;
	ulong b2f0_result = 0;

	iucv_debug(1, "entering");
	iucv_debug(1, "pathid = %d", pathid);

	parm = (iparml_control *)grab_param();

	memcpy(parm->ipuser, user_data, sizeof(parm->ipuser));
	parm->ippathid = pathid;

	b2f0_result = b2f0(QUIESCE, parm);
	release_param(parm);

	iucv_debug(1, "b2f0_result = %ld", b2f0_result);
	iucv_debug(1, "exiting");

	return b2f0_result;
}

/**
 * iucv_receive:
 * @pathid: Path identification number.
 * @buffer: Address of buffer to receive. Must be below 2G.
 * @buflen: Length of buffer to receive.
 * @msgid:  Specifies the message ID.
 * @trgcls: Specifies target class.
 * @flags1_out: Receives options for path on return.
 *    - IPNORPY (0x10)  Specifies whether a reply is required
 *    - IPPRTY (0x20)   Specifies if you want to send priority message
 *    - IPRMDATA (0x80) Specifies the data is contained in the parameter list
 * @residual_buffer: Receives the address of buffer updated by the number
 *                   of bytes you have received on return.
 * @residual_length: On return, receives one of the following values:
 *    - 0                          If the receive buffer is the same length as
 *                                 the message.
 *    - Remaining bytes in buffer  If the receive buffer is longer than the
 *                                 message.
 *    - Remaining bytes in message If the receive buffer is shorter than the
 *                                 message.
 *
 * This function receives messages that are being sent to you over established
 * paths.
 * Returns: return code from CP IUCV call; If the receive buffer is shorter
 *   than the message, always 5
 *   -EINVAL - buffer address is pointing to NULL
 */
int
iucv_receive (__u16 pathid, __u32 msgid, __u32 trgcls,
	      void *buffer, ulong buflen,
	      int *flags1_out, ulong * residual_buffer, ulong * residual_length)
{
	iparml_db *parm;
	ulong b2f0_result;
	int moved = 0;	/* number of bytes moved from parmlist to buffer */

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ipbfadr1 = (__u32) (addr_t) buffer;
	parm->ipbfln1f = (__u32) ((ulong) buflen);
	parm->ipmsgid = msgid;
	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipflags1 = (IPFGPID | IPFGMID | IPFGMCL);

	b2f0_result = b2f0(RECEIVE, parm);

	if (!b2f0_result || b2f0_result == 5) {
		if (flags1_out) {
			iucv_debug(2, "*flags1_out = %d", *flags1_out);
			*flags1_out = (parm->ipflags1 & (~0x07));
			iucv_debug(2, "*flags1_out = %d", *flags1_out);
		}

		if (!(parm->ipflags1 & IPRMDATA)) {	/*msg not in parmlist */
			if (residual_length)
				*residual_length = parm->ipbfln1f;

			if (residual_buffer)
				*residual_buffer = parm->ipbfadr1;
		} else {
			moved = min_t (unsigned long, buflen, 8);

			memcpy ((char *) buffer,
				(char *) &parm->ipbfadr1, moved);

			if (buflen < 8)
				b2f0_result = 5;

			if (residual_length)
				*residual_length = abs (buflen - 8);

			if (residual_buffer)
				*residual_buffer = (ulong) (buffer + moved);
		}
	}
	release_param(parm);

	iucv_debug(2, "exiting");
	return b2f0_result;
}

/*
 * Name: iucv_receive_array
 * Purpose: This function receives messages that are being sent to you
 *          over established paths.
 * Input: pathid - path identification number
 *        buffer - address of array of buffers
 *        buflen - total length of buffers
 *        msgid - specifies the message ID.
 *        trgcls - specifies target class
 * Output:
 *        flags1_out: Options for path.
 *          IPNORPY - 0x10 specifies whether a reply is required
 *          IPPRTY - 0x20 specifies if you want to send priority message
 *         IPRMDATA - 0x80 specifies the data is contained in the parameter list
 *       residual_buffer - address points to the current list entry IUCV
 *                         is working on.
 *       residual_length -
 *              Contains one of the following values, if the receive buffer is:
 *               The same length as the message, this field is zero.
 *               Longer than the message, this field contains the number of
 *                bytes remaining in the buffer.
 *               Shorter than the message, this field contains the residual
 *                count (that is, the number of bytes remaining in the
 *                message that does not fit into the buffer. In this case
 *		  b2f0_result = 5.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer address is NULL
 */
int
iucv_receive_array (__u16 pathid,
		    __u32 msgid, __u32 trgcls,
		    iucv_array_t * buffer, ulong buflen,
		    int *flags1_out,
		    ulong * residual_buffer, ulong * residual_length)
{
	iparml_db *parm;
	ulong b2f0_result;
	int i = 0, moved = 0, need_to_move = 8, dyn_len;

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ipbfadr1 = (__u32) ((ulong) buffer);
	parm->ipbfln1f = (__u32) buflen;
	parm->ipmsgid = msgid;
	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipflags1 = (IPBUFLST | IPFGPID | IPFGMID | IPFGMCL);

	b2f0_result = b2f0(RECEIVE, parm);

	if (!b2f0_result || b2f0_result == 5) {

		if (flags1_out) {
			iucv_debug(2, "*flags1_out = %d", *flags1_out);
			*flags1_out = (parm->ipflags1 & (~0x07));
			iucv_debug(2, "*flags1_out = %d", *flags1_out);
		}

		if (!(parm->ipflags1 & IPRMDATA)) {	/*msg not in parmlist */

			if (residual_length)
				*residual_length = parm->ipbfln1f;

			if (residual_buffer)
				*residual_buffer = parm->ipbfadr1;

		} else {
			/* copy msg from parmlist to users array. */

			while ((moved < 8) && (moved < buflen)) {
				dyn_len =
				    min_t (unsigned int,
					 (buffer + i)->length, need_to_move);

				memcpy ((char *)((ulong)((buffer + i)->address)),
					((char *) &parm->ipbfadr1) + moved,
					dyn_len);

				moved += dyn_len;
				need_to_move -= dyn_len;

				(buffer + i)->address =
				    	(__u32)
				((ulong)(__u8 *) ((ulong)(buffer + i)->address)
						+ dyn_len);

				(buffer + i)->length -= dyn_len;
				i++;
			}

			if (need_to_move)	/* buflen < 8 bytes */
				b2f0_result = 5;

			if (residual_length)
				*residual_length = abs (buflen - 8);

			if (residual_buffer) {
				if (!moved)
					*residual_buffer = (ulong) buffer;
				else
					*residual_buffer =
					    (ulong) (buffer + (i - 1));
			}

		}
	}
	release_param(parm);

	iucv_debug(2, "exiting");
	return b2f0_result;
}

/**
 * iucv_reject:
 * @pathid: Path identification number.
 * @msgid:  Message ID of the message to reject.
 * @trgcls: Target class of the message to reject.
 * Returns: return code from CP
 *
 * Refuses a specified message. Between the time you are notified of a
 * message and the time that you complete the message, the message may
 * be rejected.
 */
int
iucv_reject (__u16 pathid, __u32 msgid, __u32 trgcls)
{
	iparml_db *parm;
	ulong b2f0_result = 0;

	iucv_debug(1, "entering");
	iucv_debug(1, "pathid = %d", pathid);

	parm = (iparml_db *)grab_param();

	parm->ippathid = pathid;
	parm->ipmsgid = msgid;
	parm->iptrgcls = trgcls;
	parm->ipflags1 = (IPFGMCL | IPFGMID | IPFGPID);

	b2f0_result = b2f0(REJECT, parm);
	release_param(parm);

	iucv_debug(1, "b2f0_result = %ld", b2f0_result);
	iucv_debug(1, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_reply
 * Purpose: This function responds to the two-way messages that you
 *          receive. You must identify completely the message to
 *          which you wish to reply. ie, pathid, msgid, and trgcls.
 * Input: pathid - path identification number
 *        msgid - specifies the message ID.
 *        trgcls - specifies target class
 *        flags1 - option for path
 *                 IPPRTY- 0x20 - specifies if you want to send priority message
 *        buffer - address of reply buffer
 *        buflen - length of reply buffer
 * Output: ipbfadr2 - Address of buffer updated by the number
 *                    of bytes you have moved.
 *         ipbfln2f - Contains one of the following values:
 *              If the answer buffer is the same length as the reply, this field
 *               contains zero.
 *              If the answer buffer is longer than the reply, this field contains
 *               the number of bytes remaining in the buffer.
 *              If the answer buffer is shorter than the reply, this field contains
 *               a residual count (that is, the number of bytes remianing in the
 *               reply that does not fit into the buffer. In this
 *                case b2f0_result = 5.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer address is NULL
 */
int
iucv_reply (__u16 pathid,
	    __u32 msgid, __u32 trgcls,
	    int flags1,
	    void *buffer, ulong buflen, ulong * ipbfadr2, ulong * ipbfln2f)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ipbfadr2 = (__u32) ((ulong) buffer);
	parm->ipbfln2f = (__u32) buflen;	/* length of message */
	parm->ippathid = pathid;
	parm->ipmsgid = msgid;
	parm->iptrgcls = trgcls;
	parm->ipflags1 = (__u8) flags1;	/* priority message */

	b2f0_result = b2f0(REPLY, parm);

	if ((!b2f0_result) || (b2f0_result == 5)) {
		if (ipbfadr2)
			*ipbfadr2 = parm->ipbfadr2;
		if (ipbfln2f)
			*ipbfln2f = parm->ipbfln2f;
	}
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_reply_array
 * Purpose: This function responds to the two-way messages that you
 *          receive. You must identify completely the message to
 *          which you wish to reply. ie, pathid, msgid, and trgcls.
 *          The array identifies a list of addresses and lengths of
 *          discontiguous buffers that contains the reply data.
 * Input: pathid - path identification number
 *        msgid - specifies the message ID.
 *        trgcls - specifies target class
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        buffer - address of array of reply buffers
 *        buflen - total length of reply buffers
 * Output: ipbfadr2 - Address of buffer which IUCV is currently working on.
 *         ipbfln2f - Contains one of the following values:
 *              If the answer buffer is the same length as the reply, this field
 *               contains zero.
 *              If the answer buffer is longer than the reply, this field contains
 *               the number of bytes remaining in the buffer.
 *              If the answer buffer is shorter than the reply, this field contains
 *               a residual count (that is, the number of bytes remianing in the
 *               reply that does not fit into the buffer. In this
 *               case b2f0_result = 5.
 * Return: b2f0_result - return code from CP
 *             (-EINVAL) - buffer address is NULL
*/
int
iucv_reply_array (__u16 pathid,
		  __u32 msgid, __u32 trgcls,
		  int flags1,
		  iucv_array_t * buffer,
		  ulong buflen, ulong * ipbfadr2, ulong * ipbfln2f)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ipbfadr2 = (__u32) ((ulong) buffer);
	parm->ipbfln2f = buflen;	/* length of message */
	parm->ippathid = pathid;
	parm->ipmsgid = msgid;
	parm->iptrgcls = trgcls;
	parm->ipflags1 = (IPANSLST | flags1);

	b2f0_result = b2f0(REPLY, parm);

	if ((!b2f0_result) || (b2f0_result == 5)) {

		if (ipbfadr2)
			*ipbfadr2 = parm->ipbfadr2;
		if (ipbfln2f)
			*ipbfln2f = parm->ipbfln2f;
	}
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_reply_prmmsg
 * Purpose: This function responds to the two-way messages that you
 *          receive. You must identify completely the message to
 *          which you wish to reply. ie, pathid, msgid, and trgcls.
 *          Prmmsg signifies the data is moved into the
 *          parameter list.
 * Input: pathid - path identification number
 *        msgid - specifies the message ID.
 *        trgcls - specifies target class
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        prmmsg - 8-bytes of data to be placed into the parameter
 *                 list.
 * Output: NA
 * Return: b2f0_result - return code from CP
*/
int
iucv_reply_prmmsg (__u16 pathid,
		   __u32 msgid, __u32 trgcls, int flags1, __u8 prmmsg[8])
{
	iparml_dpl *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	parm = (iparml_dpl *)grab_param();

	parm->ippathid = pathid;
	parm->ipmsgid = msgid;
	parm->iptrgcls = trgcls;
	memcpy(parm->iprmmsg, prmmsg, sizeof (parm->iprmmsg));
	parm->ipflags1 = (IPRMDATA | flags1);

	b2f0_result = b2f0(REPLY, parm);
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/**
 * iucv_resume:
 * @pathid:    Path identification number
 * @user_data: 16-byte of user data
 *
 * This function restores communication over a quiesced path.
 * Returns: return code from CP
 */
int
iucv_resume (__u16 pathid, __u8 user_data[16])
{
	iparml_control *parm;
	ulong b2f0_result = 0;

	iucv_debug(1, "entering");
	iucv_debug(1, "pathid = %d", pathid);

	parm = (iparml_control *)grab_param();

	memcpy (parm->ipuser, user_data, sizeof (*user_data));
	parm->ippathid = pathid;

	b2f0_result = b2f0(RESUME, parm);
	release_param(parm);

	iucv_debug(1, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_send
 * Purpose: sends messages
 * Input: pathid - ushort, pathid
 *        msgid  - ulong *, id of message returned to caller
 *        trgcls - ulong, target message class
 *        srccls - ulong, source message class
 *        msgtag - ulong, message tag
 *	  flags1  - Contains options for this path.
 *		IPPRTY - Ox20 - specifies if you want to send a priority message.
 *        buffer - pointer to buffer
 *        buflen - ulong, length of buffer
 * Output: b2f0_result - return code from b2f0 call
 *         msgid - returns message id
 */
int
iucv_send (__u16 pathid, __u32 * msgid,
	   __u32 trgcls, __u32 srccls,
	   __u32 msgtag, int flags1, void *buffer, ulong buflen)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ipbfadr1 = (__u32) ((ulong) buffer);
	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipbfln1f = (__u32) buflen;	/* length of message */
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipflags1 = (IPNORPY | flags1);	/* one way priority message */

	b2f0_result = b2f0(SEND, parm);

	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_send_array
 * Purpose: This function transmits data to another application.
 *          The contents of buffer is the address of the array of
 *          addresses and lengths of discontiguous buffers that hold
 *          the message text. This is a one-way message and the
 *          receiver will not reply to the message.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - specifies a tag to be associated witht the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        buffer - address of array of send buffers
 *        buflen - total length of send buffers
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer address is NULL
 */
int
iucv_send_array (__u16 pathid,
		 __u32 * msgid,
		 __u32 trgcls,
		 __u32 srccls,
		 __u32 msgtag, int flags1, iucv_array_t * buffer, ulong buflen)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipbfadr1 = (__u32) ((ulong) buffer);
	parm->ipbfln1f = (__u32) buflen;	/* length of message */
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipflags1 = (IPNORPY | IPBUFLST | flags1);
	b2f0_result = b2f0(SEND, parm);

	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");
	return b2f0_result;
}

/*
 * Name: iucv_send_prmmsg
 * Purpose: This function transmits data to another application.
 *          Prmmsg specifies that the 8-bytes of data are to be moved
 *          into the parameter list. This is a one-way message and the
 *          receiver will not reply to the message.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - specifies a tag to be associated with the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        prmmsg - 8-bytes of data to be placed into parameter list
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
*/
int
iucv_send_prmmsg (__u16 pathid,
		  __u32 * msgid,
		  __u32 trgcls,
		  __u32 srccls, __u32 msgtag, int flags1, __u8 prmmsg[8])
{
	iparml_dpl *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	parm = (iparml_dpl *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipflags1 = (IPRMDATA | IPNORPY | flags1);
	memcpy(parm->iprmmsg, prmmsg, sizeof(parm->iprmmsg));

	b2f0_result = b2f0(SEND, parm);

	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_send2way
 * Purpose: This function transmits data to another application.
 *          Data to be transmitted is in a buffer. The receiver
 *          of the send is expected to reply to the message and
 *          a buffer is provided into which IUCV moves the reply
 *          to this message.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - specifies a tag associated with the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        buffer - address of send buffer
 *        buflen - length of send buffer
 *        ansbuf - address of buffer to reply with
 *        anslen - length of buffer to reply with
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer or ansbuf address is NULL
 */
int
iucv_send2way (__u16 pathid,
	       __u32 * msgid,
	       __u32 trgcls,
	       __u32 srccls,
	       __u32 msgtag,
	       int flags1,
	       void *buffer, ulong buflen, void *ansbuf, ulong anslen)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer || !ansbuf)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipbfadr1 = (__u32) ((ulong) buffer);
	parm->ipbfln1f = (__u32) buflen;	/* length of message */
	parm->ipbfadr2 = (__u32) ((ulong) ansbuf);
	parm->ipbfln2f = (__u32) anslen;
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipflags1 = flags1;	/* priority message */

	b2f0_result = b2f0(SEND, parm);

	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_send2way_array
 * Purpose: This function transmits data to another application.
 *          The contents of buffer is the address of the array of
 *          addresses and lengths of discontiguous buffers that hold
 *          the message text. The receiver of the send is expected to
 *          reply to the message and a buffer is provided into which
 *          IUCV moves the reply to this message.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - spcifies a tag to be associated with the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        buffer - address of array of send buffers
 *        buflen - total length of send buffers
 *        ansbuf - address of buffer to reply with
 *        anslen - length of buffer to reply with
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer address is NULL
 */
int
iucv_send2way_array (__u16 pathid,
		     __u32 * msgid,
		     __u32 trgcls,
		     __u32 srccls,
		     __u32 msgtag,
		     int flags1,
		     iucv_array_t * buffer,
		     ulong buflen, iucv_array_t * ansbuf, ulong anslen)
{
	iparml_db *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!buffer || !ansbuf)
		return -EINVAL;

	parm = (iparml_db *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipbfadr1 = (__u32) ((ulong) buffer);
	parm->ipbfln1f = (__u32) buflen;	/* length of message */
	parm->ipbfadr2 = (__u32) ((ulong) ansbuf);
	parm->ipbfln2f = (__u32) anslen;
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipflags1 = (IPBUFLST | IPANSLST | flags1);
	b2f0_result = b2f0(SEND, parm);
	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");
	return b2f0_result;
}

/*
 * Name: iucv_send2way_prmmsg
 * Purpose: This function transmits data to another application.
 *          Prmmsg specifies that the 8-bytes of data are to be moved
 *          into the parameter list. This is a two-way message and the
 *          receiver of the message is expected to reply. A buffer
 *          is provided into which IUCV moves the reply to this
 *          message.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - specifies a tag to be associated with the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        prmmsg - 8-bytes of data to be placed in parameter list
 *        ansbuf - address of buffer to reply with
 *        anslen - length of buffer to reply with
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - buffer address is NULL
*/
int
iucv_send2way_prmmsg (__u16 pathid,
		      __u32 * msgid,
		      __u32 trgcls,
		      __u32 srccls,
		      __u32 msgtag,
		      ulong flags1, __u8 prmmsg[8], void *ansbuf, ulong anslen)
{
	iparml_dpl *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!ansbuf)
		return -EINVAL;

	parm = (iparml_dpl *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipbfadr2 = (__u32) ((ulong) ansbuf);
	parm->ipbfln2f = (__u32) anslen;
	parm->ipflags1 = (IPRMDATA | flags1);	/* message in prmlist */
	memcpy(parm->iprmmsg, prmmsg, sizeof(parm->iprmmsg));

	b2f0_result = b2f0(SEND, parm);

	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");

	return b2f0_result;
}

/*
 * Name: iucv_send2way_prmmsg_array
 * Purpose: This function transmits data to another application.
 *          Prmmsg specifies that the 8-bytes of data are to be moved
 *          into the parameter list. This is a two-way message and the
 *          receiver of the message is expected to reply. A buffer
 *          is provided into which IUCV moves the reply to this
 *          message. The contents of ansbuf is the address of the
 *          array of addresses and lengths of discontiguous buffers
 *          that contain the reply.
 * Input: pathid - path identification number
 *        trgcls - specifies target class
 *        srccls - specifies the source message class
 *        msgtag - specifies a tag to be associated with the message
 *        flags1 - option for path
 *                 IPPRTY- specifies if you want to send priority message
 *        prmmsg - 8-bytes of data to be placed into the parameter list
 *        ansbuf - address of buffer to reply with
 *        anslen - length of buffer to reply with
 * Output: msgid - specifies the message ID.
 * Return: b2f0_result - return code from CP
 *         (-EINVAL) - ansbuf address is NULL
 */
int
iucv_send2way_prmmsg_array (__u16 pathid,
			    __u32 * msgid,
			    __u32 trgcls,
			    __u32 srccls,
			    __u32 msgtag,
			    int flags1,
			    __u8 prmmsg[8],
			    iucv_array_t * ansbuf, ulong anslen)
{
	iparml_dpl *parm;
	ulong b2f0_result;

	iucv_debug(2, "entering");

	if (!ansbuf)
		return -EINVAL;

	parm = (iparml_dpl *)grab_param();

	parm->ippathid = pathid;
	parm->iptrgcls = trgcls;
	parm->ipsrccls = srccls;
	parm->ipmsgtag = msgtag;
	parm->ipbfadr2 = (__u32) ((ulong) ansbuf);
	parm->ipbfln2f = (__u32) anslen;
	parm->ipflags1 = (IPRMDATA | IPANSLST | flags1);
	memcpy(parm->iprmmsg, prmmsg, sizeof(parm->iprmmsg));
	b2f0_result = b2f0(SEND, parm);
	if ((!b2f0_result) && (msgid))
		*msgid = parm->ipmsgid;
	release_param(parm);

	iucv_debug(2, "exiting");
	return b2f0_result;
}

void
iucv_setmask_cpuid (void *result)
{
        iparml_set_mask *parm;

        iucv_debug(1, "entering");
        parm = (iparml_set_mask *)grab_param();
        parm->ipmask = *((__u8*)result);
        *((ulong *)result) = b2f0(SETMASK, parm);
        release_param(parm);

        iucv_debug(1, "b2f0_result = %ld", *((ulong *)result));
        iucv_debug(1, "exiting");
}

/*
 * Name: iucv_setmask
 * Purpose: This function enables or disables the following IUCV
 *          external interruptions: Nonpriority and priority message
 *          interrupts, nonpriority and priority reply interrupts.
 * Input: SetMaskFlag - options for interrupts
 *           0x80 - Nonpriority_MessagePendingInterruptsFlag
 *           0x40 - Priority_MessagePendingInterruptsFlag
 *           0x20 - Nonpriority_MessageCompletionInterruptsFlag
 *           0x10 - Priority_MessageCompletionInterruptsFlag
 *           0x08 - IUCVControlInterruptsFlag
 * Output: NA
 * Return: b2f0_result - return code from CP
*/
int
iucv_setmask (int SetMaskFlag)
{
	union {
		ulong result;
		__u8  param;
	} u;
	int cpu;

	u.param = SetMaskFlag;
	cpu = get_cpu();
	smp_call_function_on(iucv_setmask_cpuid, &u, 0, 1, iucv_cpuid);
	put_cpu();

	return u.result;
}

/**
 * iucv_sever:
 * @pathid:    Path identification number
 * @user_data: 16-byte of user data
 *
 * This function terminates an iucv path.
 * Returns: return code from CP
 */
int
iucv_sever(__u16 pathid, __u8 user_data[16])
{
	iparml_control *parm;
	ulong b2f0_result = 0;

	iucv_debug(1, "entering");
	parm = (iparml_control *)grab_param();

	memcpy(parm->ipuser, user_data, sizeof(parm->ipuser));
	parm->ippathid = pathid;

	b2f0_result = b2f0(SEVER, parm);

	if (!b2f0_result)
		iucv_remove_pathid(pathid);
	release_param(parm);

	iucv_debug(1, "exiting");
	return b2f0_result;
}

/*
 * Interrupt Handlers
 *******************************************************************************/

/**
 * iucv_irq_handler:
 * @regs: Current registers
 * @code: irq code
 *
 * Handles external interrupts coming in from CP.
 * Places the interrupt buffer on a queue and schedules iucv_tasklet_handler().
 */
static void
iucv_irq_handler(struct pt_regs *regs, __u16 code)
{
	iucv_irqdata *irqdata;

	irqdata = kmalloc(sizeof(iucv_irqdata), GFP_ATOMIC);
	if (!irqdata) {
		printk(KERN_WARNING "%s: out of memory\n", __FUNCTION__);
		return;
	}

	memcpy(&irqdata->data, iucv_external_int_buffer,
	       sizeof(iucv_GeneralInterrupt));

	spin_lock(&iucv_irq_queue_lock);
	list_add_tail(&irqdata->queue, &iucv_irq_queue);
	spin_unlock(&iucv_irq_queue_lock);

	tasklet_schedule(&iucv_tasklet);
}

/**
 * iucv_do_int:
 * @int_buf: Pointer to copy of external interrupt buffer
 *
 * The workhorse for handling interrupts queued by iucv_irq_handler().
 * This function is called from the bottom half iucv_tasklet_handler().
 */
static void
iucv_do_int(iucv_GeneralInterrupt * int_buf)
{
	handler *h = NULL;
	struct list_head *lh;
	ulong flags;
	iucv_interrupt_ops_t *interrupt = NULL;	/* interrupt addresses */
	__u8 temp_buff1[24], temp_buff2[24];	/* masked handler id. */
	int rc = 0, j = 0;
	__u8 no_listener[16] = "NO LISTENER";

	iucv_debug(2, "entering, pathid %d, type %02X",
		 int_buf->ippathid, int_buf->iptype);
	iucv_dumpit("External Interrupt Buffer:",
		    int_buf, sizeof(iucv_GeneralInterrupt));

	ASCEBC (no_listener, 16);

	if (int_buf->iptype != 01) {
		if ((int_buf->ippathid) > (max_connections - 1)) {
			printk(KERN_WARNING "%s: Got interrupt with pathid %d"
			       " > max_connections (%ld)\n", __FUNCTION__,
			       int_buf->ippathid, max_connections - 1);
		} else {
			h = iucv_pathid_table[int_buf->ippathid];
			interrupt = h->interrupt_table;
			iucv_dumpit("Handler:", h, sizeof(handler));
		}
	}

	/* end of if statement */
	switch (int_buf->iptype) {
		case 0x01:		/* connection pending */
			if (messagesDisabled) {
			    iucv_setmask(~0);
			    messagesDisabled = 0;
			}
			spin_lock_irqsave(&iucv_lock, flags);
			list_for_each(lh, &iucv_handler_table) {
				h = list_entry(lh, handler, list);
				memcpy(temp_buff1, &(int_buf->ipvmid), 24);
				memcpy(temp_buff2, &(h->id.userid), 24);
				for (j = 0; j < 24; j++) {
					temp_buff1[j] &= (h->id.mask)[j];
					temp_buff2[j] &= (h->id.mask)[j];
				}
				
				iucv_dumpit("temp_buff1:",
					    temp_buff1, sizeof(temp_buff1));
				iucv_dumpit("temp_buff2",
					    temp_buff2, sizeof(temp_buff2));
				
				if (!memcmp (temp_buff1, temp_buff2, 24)) {
					
					iucv_debug(2,
						   "found a matching handler");
					break;
				} else
					h = NULL;
			}
			spin_unlock_irqrestore (&iucv_lock, flags);
			if (h) {
				/* ADD PATH TO PATHID TABLE */
				rc = iucv_add_pathid(int_buf->ippathid, h);
				if (rc) {
					iucv_sever (int_buf->ippathid,
						    no_listener);
					iucv_debug(1,
						   "add_pathid failed, rc = %d",
						   rc);
				} else {
					interrupt = h->interrupt_table;
					if (interrupt->ConnectionPending) {
						EBCASC (int_buf->ipvmid, 8);
						interrupt->ConnectionPending(
							(iucv_ConnectionPending *)int_buf,
							h->pgm_data);
					} else
						iucv_sever(int_buf->ippathid,
							   no_listener);
				}
			} else
				iucv_sever(int_buf->ippathid, no_listener);
			break;
			
		case 0x02:		/*connection complete */
			if (messagesDisabled) {
			    iucv_setmask(~0);
			    messagesDisabled = 0;
			}
			if (h) {
				if (interrupt->ConnectionComplete)
				{
					interrupt->ConnectionComplete(
						(iucv_ConnectionComplete *)int_buf,
						h->pgm_data);
				}
				else
					iucv_debug(1,
						   "ConnectionComplete not called");
			} else
				iucv_sever(int_buf->ippathid, no_listener);
			break;
			
		case 0x03:		/* connection severed */
			if (messagesDisabled) {
			    iucv_setmask(~0);
			    messagesDisabled = 0;
			}
			if (h) {
				if (interrupt->ConnectionSevered)
					interrupt->ConnectionSevered(
						(iucv_ConnectionSevered *)int_buf,
						h->pgm_data);
				
				else
					iucv_sever (int_buf->ippathid, no_listener);
			} else
				iucv_sever(int_buf->ippathid, no_listener);
			break;
			
		case 0x04:		/* connection quiesced */
			if (messagesDisabled) {
			    iucv_setmask(~0);
			    messagesDisabled = 0;
			}
			if (h) {
				if (interrupt->ConnectionQuiesced)
					interrupt->ConnectionQuiesced(
						(iucv_ConnectionQuiesced *)int_buf,
						h->pgm_data);
				else
					iucv_debug(1,
						   "ConnectionQuiesced not called");
			}
			break;
			
		case 0x05:		/* connection resumed */
			if (messagesDisabled) {
			    iucv_setmask(~0);
			    messagesDisabled = 0;
			}
			if (h) {
				if (interrupt->ConnectionResumed)
					interrupt->ConnectionResumed(
						(iucv_ConnectionResumed *)int_buf,
						h->pgm_data);
				else
					iucv_debug(1,
						   "ConnectionResumed not called");
			}
			break;
			
		case 0x06:		/* priority message complete */
		case 0x07:		/* nonpriority message complete */
			if (h) {
				if (interrupt->MessageComplete)
					interrupt->MessageComplete(
						(iucv_MessageComplete *)int_buf,
						h->pgm_data);
				else
					iucv_debug(2,
						   "MessageComplete not called");
			}
			break;
			
		case 0x08:		/* priority message pending  */
		case 0x09:		/* nonpriority message pending  */
			if (h) {
				if (interrupt->MessagePending)
					interrupt->MessagePending(
						(iucv_MessagePending *) int_buf,
						h->pgm_data);
				else
					iucv_debug(2,
						   "MessagePending not called");
			}
			break;
		default:		/* unknown iucv type */
			printk(KERN_WARNING "%s: unknown iucv interrupt\n",
			       __FUNCTION__);
			break;
	}			/* end switch */
	
	iucv_debug(2, "exiting pathid %d, type %02X",
		 int_buf->ippathid, int_buf->iptype);

	return;
}

/**
 * iucv_tasklet_handler:
 *
 * This function loops over the queue of irq buffers and runs iucv_do_int()
 * on every queue element.
 */
static void
iucv_tasklet_handler(unsigned long ignored)
{
	struct list_head head;
	struct list_head *next;
	ulong  flags;

	spin_lock_irqsave(&iucv_irq_queue_lock, flags);
	list_add(&head, &iucv_irq_queue);
	list_del_init(&iucv_irq_queue);
	spin_unlock_irqrestore (&iucv_irq_queue_lock, flags);

	next = head.next;
	while (next != &head) {
		iucv_irqdata *p = list_entry(next, iucv_irqdata, queue);

		next = next->next;
		iucv_do_int(&p->data);
		kfree(p);
	}

	return;
}

subsys_initcall(iucv_init);
module_exit(iucv_exit);

/**
 * Export all public stuff
 */
EXPORT_SYMBOL (iucv_bus);
EXPORT_SYMBOL (iucv_root);
EXPORT_SYMBOL (iucv_accept);
EXPORT_SYMBOL (iucv_connect);
#if 0
EXPORT_SYMBOL (iucv_purge);
EXPORT_SYMBOL (iucv_query_maxconn);
EXPORT_SYMBOL (iucv_query_bufsize);
EXPORT_SYMBOL (iucv_quiesce);
#endif
EXPORT_SYMBOL (iucv_receive);
#if 0
EXPORT_SYMBOL (iucv_receive_array);
#endif
EXPORT_SYMBOL (iucv_reject);
#if 0
EXPORT_SYMBOL (iucv_reply);
EXPORT_SYMBOL (iucv_reply_array);
EXPORT_SYMBOL (iucv_resume);
#endif
EXPORT_SYMBOL (iucv_reply_prmmsg);
EXPORT_SYMBOL (iucv_send);
EXPORT_SYMBOL (iucv_send2way);
EXPORT_SYMBOL (iucv_send2way_array);
EXPORT_SYMBOL (iucv_send2way_prmmsg);
EXPORT_SYMBOL (iucv_send2way_prmmsg_array);
#if 0
EXPORT_SYMBOL (iucv_send_array);
EXPORT_SYMBOL (iucv_send_prmmsg);
EXPORT_SYMBOL (iucv_setmask);
#endif
EXPORT_SYMBOL (iucv_sever);
EXPORT_SYMBOL (iucv_register_program);
EXPORT_SYMBOL (iucv_unregister_program);