Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
/*
 * IUCV base infrastructure.
 *
 * Copyright IBM Corp. 2001, 2009
 *
 * 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)
 *    Rewritten for af_iucv:
 *	Martin Schwidefsky <schwidefsky@de.ibm.com>
 *    PM functions:
 *	Ursula Braun (ursula.braun@de.ibm.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.
 */

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

#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/moduleparam.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 <linux/cpu.h>
#include <linux/reboot.h>
#include <net/iucv/iucv.h>
#include <linux/atomic.h>
#include <asm/ebcdic.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/smp.h>

/*
 * 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.
 * IPTRGCLS - Indicates you have specified a target class.
 * IPFGPID  - Indicates you have specified a pathid.
 * IPFGMID  - Indicates you have specified a message ID.
 * IPNORPY  - Indicates a one-way message. No reply expected.
 * IPALL    - Indicates that all paths are affected.
 */
#define IUCV_IPSRCCLS	0x01
#define IUCV_IPTRGCLS	0x01
#define IUCV_IPFGPID	0x02
#define IUCV_IPFGMID	0x04
#define IUCV_IPNORPY	0x10
#define IUCV_IPALL	0x80

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

enum iucv_pm_states {
	IUCV_PM_INITIAL = 0,
	IUCV_PM_FREEZING = 1,
	IUCV_PM_THAWING = 2,
	IUCV_PM_RESTORING = 3,
};
static enum iucv_pm_states iucv_pm_state;

static int iucv_pm_prepare(struct device *);
static void iucv_pm_complete(struct device *);
static int iucv_pm_freeze(struct device *);
static int iucv_pm_thaw(struct device *);
static int iucv_pm_restore(struct device *);

static const struct dev_pm_ops iucv_pm_ops = {
	.prepare = iucv_pm_prepare,
	.complete = iucv_pm_complete,
	.freeze = iucv_pm_freeze,
	.thaw = iucv_pm_thaw,
	.restore = iucv_pm_restore,
};

struct bus_type iucv_bus = {
	.name = "iucv",
	.match = iucv_bus_match,
	.pm = &iucv_pm_ops,
};
EXPORT_SYMBOL(iucv_bus);

struct device *iucv_root;
EXPORT_SYMBOL(iucv_root);

static int iucv_available;

/* General IUCV interrupt structure */
struct iucv_irq_data {
	u16 ippathid;
	u8  ipflags1;
	u8  iptype;
	u32 res2[8];
};

struct iucv_irq_list {
	struct list_head list;
	struct iucv_irq_data data;
};

static struct iucv_irq_data *iucv_irq_data[NR_CPUS];
static cpumask_t iucv_buffer_cpumask = { CPU_BITS_NONE };
static cpumask_t iucv_irq_cpumask = { CPU_BITS_NONE };

/*
 * Queue of interrupt buffers lock for delivery via the tasklet
 * (fast but can't call smp_call_function).
 */
static LIST_HEAD(iucv_task_queue);

/*
 * The tasklet for fast delivery of iucv interrupts.
 */
static void iucv_tasklet_fn(unsigned long);
static DECLARE_TASKLET(iucv_tasklet, iucv_tasklet_fn,0);

/*
 * Queue of interrupt buffers for delivery via a work queue
 * (slower but can call smp_call_function).
 */
static LIST_HEAD(iucv_work_queue);

/*
 * The work element to deliver path pending interrupts.
 */
static void iucv_work_fn(struct work_struct *work);
static DECLARE_WORK(iucv_work, iucv_work_fn);

/*
 * Spinlock protecting task and work queue.
 */
static DEFINE_SPINLOCK(iucv_queue_lock);

enum iucv_command_codes {
	IUCV_QUERY = 0,
	IUCV_RETRIEVE_BUFFER = 2,
	IUCV_SEND = 4,
	IUCV_RECEIVE = 5,
	IUCV_REPLY = 6,
	IUCV_REJECT = 8,
	IUCV_PURGE = 9,
	IUCV_ACCEPT = 10,
	IUCV_CONNECT = 11,
	IUCV_DECLARE_BUFFER = 12,
	IUCV_QUIESCE = 13,
	IUCV_RESUME = 14,
	IUCV_SEVER = 15,
	IUCV_SETMASK = 16,
	IUCV_SETCONTROLMASK = 17,
};

/*
 * Error messages that are used with the iucv_sever function. They get
 * converted to EBCDIC.
 */
static char iucv_error_no_listener[16] = "NO LISTENER";
static char iucv_error_no_memory[16] = "NO MEMORY";
static char iucv_error_pathid[16] = "INVALID PATHID";

/*
 * iucv_handler_list: List of registered handlers.
 */
static LIST_HEAD(iucv_handler_list);

/*
 * iucv_path_table: an array of iucv_path structures.
 */
static struct iucv_path **iucv_path_table;
static unsigned long iucv_max_pathid;

/*
 * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
 */
static DEFINE_SPINLOCK(iucv_table_lock);

/*
 * iucv_active_cpu: contains the number of the cpu executing the tasklet
 * or the work handler. Needed for iucv_path_sever called from tasklet.
 */
static int iucv_active_cpu = -1;

/*
 * Mutex and wait queue for iucv_register/iucv_unregister.
 */
static DEFINE_MUTEX(iucv_register_mutex);

/*
 * Counter for number of non-smp capable handlers.
 */
static int iucv_nonsmp_handler;

/*
 * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
 * iucv_path_quiesce and iucv_path_sever.
 */
struct iucv_cmd_control {
	u16 ippathid;
	u8  ipflags1;
	u8  iprcode;
	u16 ipmsglim;
	u16 res1;
	u8  ipvmid[8];
	u8  ipuser[16];
	u8  iptarget[8];
} __attribute__ ((packed,aligned(8)));

/*
 * Data in parameter list iucv structure. Used by iucv_message_send,
 * iucv_message_send2way and iucv_message_reply.
 */
struct iucv_cmd_dpl {
	u16 ippathid;
	u8  ipflags1;
	u8  iprcode;
	u32 ipmsgid;
	u32 iptrgcls;
	u8  iprmmsg[8];
	u32 ipsrccls;
	u32 ipmsgtag;
	u32 ipbfadr2;
	u32 ipbfln2f;
	u32 res;
} __attribute__ ((packed,aligned(8)));

/*
 * Data in buffer iucv structure. Used by iucv_message_receive,
 * iucv_message_reject, iucv_message_send, iucv_message_send2way
 * and iucv_declare_cpu.
 */
struct iucv_cmd_db {
	u16 ippathid;
	u8  ipflags1;
	u8  iprcode;
	u32 ipmsgid;
	u32 iptrgcls;
	u32 ipbfadr1;
	u32 ipbfln1f;
	u32 ipsrccls;
	u32 ipmsgtag;
	u32 ipbfadr2;
	u32 ipbfln2f;
	u32 res;
} __attribute__ ((packed,aligned(8)));

/*
 * Purge message iucv structure. Used by iucv_message_purge.
 */
struct iucv_cmd_purge {
	u16 ippathid;
	u8  ipflags1;
	u8  iprcode;
	u32 ipmsgid;
	u8  ipaudit[3];
	u8  res1[5];
	u32 res2;
	u32 ipsrccls;
	u32 ipmsgtag;
	u32 res3[3];
} __attribute__ ((packed,aligned(8)));

/*
 * Set mask iucv structure. Used by iucv_enable_cpu.
 */
struct iucv_cmd_set_mask {
	u8  ipmask;
	u8  res1[2];
	u8  iprcode;
	u32 res2[9];
} __attribute__ ((packed,aligned(8)));

union iucv_param {
	struct iucv_cmd_control ctrl;
	struct iucv_cmd_dpl dpl;
	struct iucv_cmd_db db;
	struct iucv_cmd_purge purge;
	struct iucv_cmd_set_mask set_mask;
};

/*
 * Anchor for per-cpu IUCV command parameter block.
 */
static union iucv_param *iucv_param[NR_CPUS];
static union iucv_param *iucv_param_irq[NR_CPUS];

/**
 * iucv_call_b2f0
 * @code: identifier of IUCV call to CP.
 * @parm: pointer to a struct iucv_parm block
 *
 * Calls CP to execute IUCV commands.
 *
 * Returns the result of the CP IUCV call.
 */
static inline int iucv_call_b2f0(int command, union iucv_param *parm)
{
	register unsigned long reg0 asm ("0");
	register unsigned long reg1 asm ("1");
	int ccode;

	reg0 = command;
	reg1 = virt_to_phys(parm);
	asm volatile(
		"	.long 0xb2f01000\n"
		"	ipm	%0\n"
		"	srl	%0,28\n"
		: "=d" (ccode), "=m" (*parm), "+d" (reg0), "+a" (reg1)
		:  "m" (*parm) : "cc");
	return (ccode == 1) ? parm->ctrl.iprcode : ccode;
}

/**
 * iucv_query_maxconn
 *
 * Determines the maximum number of connections that may be established.
 *
 * Returns the maximum number of connections or -EPERM is IUCV is not
 * available.
 */
static int iucv_query_maxconn(void)
{
	register unsigned long reg0 asm ("0");
	register unsigned long reg1 asm ("1");
	void *param;
	int ccode;

	param = kzalloc(sizeof(union iucv_param), GFP_KERNEL|GFP_DMA);
	if (!param)
		return -ENOMEM;
	reg0 = IUCV_QUERY;
	reg1 = (unsigned long) param;
	asm volatile (
		"	.long	0xb2f01000\n"
		"	ipm	%0\n"
		"	srl	%0,28\n"
		: "=d" (ccode), "+d" (reg0), "+d" (reg1) : : "cc");
	if (ccode == 0)
		iucv_max_pathid = reg1;
	kfree(param);
	return ccode ? -EPERM : 0;
}

/**
 * iucv_allow_cpu
 * @data: unused
 *
 * Allow iucv interrupts on this cpu.
 */
static void iucv_allow_cpu(void *data)
{
	int cpu = smp_processor_id();
	union iucv_param *parm;

	/*
	 * Enable all iucv interrupts.
	 * ipmask contains bits for the different interrupts
	 *	0x80 - Flag to allow nonpriority message pending interrupts
	 *	0x40 - Flag to allow priority message pending interrupts
	 *	0x20 - Flag to allow nonpriority message completion interrupts
	 *	0x10 - Flag to allow priority message completion interrupts
	 *	0x08 - Flag to allow IUCV control interrupts
	 */
	parm = iucv_param_irq[cpu];
	memset(parm, 0, sizeof(union iucv_param));
	parm->set_mask.ipmask = 0xf8;
	iucv_call_b2f0(IUCV_SETMASK, parm);

	/*
	 * Enable all iucv control interrupts.
	 * ipmask contains bits for the different interrupts
	 *	0x80 - Flag to allow pending connections interrupts
	 *	0x40 - Flag to allow connection complete interrupts
	 *	0x20 - Flag to allow connection severed interrupts
	 *	0x10 - Flag to allow connection quiesced interrupts
	 *	0x08 - Flag to allow connection resumed interrupts
	 */
	memset(parm, 0, sizeof(union iucv_param));
	parm->set_mask.ipmask = 0xf8;
	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
	/* Set indication that iucv interrupts are allowed for this cpu. */
	cpumask_set_cpu(cpu, &iucv_irq_cpumask);
}

/**
 * iucv_block_cpu
 * @data: unused
 *
 * Block iucv interrupts on this cpu.
 */
static void iucv_block_cpu(void *data)
{
	int cpu = smp_processor_id();
	union iucv_param *parm;

	/* Disable all iucv interrupts. */
	parm = iucv_param_irq[cpu];
	memset(parm, 0, sizeof(union iucv_param));
	iucv_call_b2f0(IUCV_SETMASK, parm);

	/* Clear indication that iucv interrupts are allowed for this cpu. */
	cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
}

/**
 * iucv_block_cpu_almost
 * @data: unused
 *
 * Allow connection-severed interrupts only on this cpu.
 */
static void iucv_block_cpu_almost(void *data)
{
	int cpu = smp_processor_id();
	union iucv_param *parm;

	/* Allow iucv control interrupts only */
	parm = iucv_param_irq[cpu];
	memset(parm, 0, sizeof(union iucv_param));
	parm->set_mask.ipmask = 0x08;
	iucv_call_b2f0(IUCV_SETMASK, parm);
	/* Allow iucv-severed interrupt only */
	memset(parm, 0, sizeof(union iucv_param));
	parm->set_mask.ipmask = 0x20;
	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);

	/* Clear indication that iucv interrupts are allowed for this cpu. */
	cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
}

/**
 * iucv_declare_cpu
 * @data: unused
 *
 * Declare a interrupt buffer on this cpu.
 */
static void iucv_declare_cpu(void *data)
{
	int cpu = smp_processor_id();
	union iucv_param *parm;
	int rc;

	if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
		return;

	/* Declare interrupt buffer. */
	parm = iucv_param_irq[cpu];
	memset(parm, 0, sizeof(union iucv_param));
	parm->db.ipbfadr1 = virt_to_phys(iucv_irq_data[cpu]);
	rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
	if (rc) {
		char *err = "Unknown";
		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;
		}
		pr_warning("Defining an interrupt buffer on CPU %i"
			   " failed with 0x%02x (%s)\n", cpu, rc, err);
		return;
	}

	/* Set indication that an iucv buffer exists for this cpu. */
	cpumask_set_cpu(cpu, &iucv_buffer_cpumask);

	if (iucv_nonsmp_handler == 0 || cpumask_empty(&iucv_irq_cpumask))
		/* Enable iucv interrupts on this cpu. */
		iucv_allow_cpu(NULL);
	else
		/* Disable iucv interrupts on this cpu. */
		iucv_block_cpu(NULL);
}

/**
 * iucv_retrieve_cpu
 * @data: unused
 *
 * Retrieve interrupt buffer on this cpu.
 */
static void iucv_retrieve_cpu(void *data)
{
	int cpu = smp_processor_id();
	union iucv_param *parm;

	if (!cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
		return;

	/* Block iucv interrupts. */
	iucv_block_cpu(NULL);

	/* Retrieve interrupt buffer. */
	parm = iucv_param_irq[cpu];
	iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);

	/* Clear indication that an iucv buffer exists for this cpu. */
	cpumask_clear_cpu(cpu, &iucv_buffer_cpumask);
}

/**
 * iucv_setmask_smp
 *
 * Allow iucv interrupts on all cpus.
 */
static void iucv_setmask_mp(void)
{
	int cpu;

	get_online_cpus();
	for_each_online_cpu(cpu)
		/* Enable all cpus with a declared buffer. */
		if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask) &&
		    !cpumask_test_cpu(cpu, &iucv_irq_cpumask))
			smp_call_function_single(cpu, iucv_allow_cpu,
						 NULL, 1);
	put_online_cpus();
}

/**
 * iucv_setmask_up
 *
 * Allow iucv interrupts on a single cpu.
 */
static void iucv_setmask_up(void)
{
	cpumask_t cpumask;
	int cpu;

	/* Disable all cpu but the first in cpu_irq_cpumask. */
	cpumask_copy(&cpumask, &iucv_irq_cpumask);
	cpumask_clear_cpu(cpumask_first(&iucv_irq_cpumask), &cpumask);
	for_each_cpu(cpu, &cpumask)
		smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
}

/**
 * iucv_enable
 *
 * This function makes iucv ready for use. It allocates the pathid
 * table, declares an iucv interrupt buffer and enables the iucv
 * interrupts. Called when the first user has registered an iucv
 * handler.
 */
static int iucv_enable(void)
{
	size_t alloc_size;
	int cpu, rc;

	get_online_cpus();
	rc = -ENOMEM;
	alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
	iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
	if (!iucv_path_table)
		goto out;
	/* Declare per cpu buffers. */
	rc = -EIO;
	for_each_online_cpu(cpu)
		smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
	if (cpumask_empty(&iucv_buffer_cpumask))
		/* No cpu could declare an iucv buffer. */
		goto out;
	put_online_cpus();
	return 0;
out:
	kfree(iucv_path_table);
	iucv_path_table = NULL;
	put_online_cpus();
	return rc;
}

/**
 * iucv_disable
 *
 * This function shuts down iucv. It disables iucv interrupts, retrieves
 * the iucv interrupt buffer and frees the pathid table. Called after the
 * last user unregister its iucv handler.
 */
static void iucv_disable(void)
{
	get_online_cpus();
	on_each_cpu(iucv_retrieve_cpu, NULL, 1);
	kfree(iucv_path_table);
	iucv_path_table = NULL;
	put_online_cpus();
}

static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
				     unsigned long action, void *hcpu)
{
	cpumask_t cpumask;
	long cpu = (long) hcpu;

	switch (action) {
	case CPU_UP_PREPARE:
	case CPU_UP_PREPARE_FROZEN:
		iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
					GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_irq_data[cpu])
			return notifier_from_errno(-ENOMEM);

		iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
				     GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_param[cpu]) {
			kfree(iucv_irq_data[cpu]);
			iucv_irq_data[cpu] = NULL;
			return notifier_from_errno(-ENOMEM);
		}
		iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
					GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_param_irq[cpu]) {
			kfree(iucv_param[cpu]);
			iucv_param[cpu] = NULL;
			kfree(iucv_irq_data[cpu]);
			iucv_irq_data[cpu] = NULL;
			return notifier_from_errno(-ENOMEM);
		}
		break;
	case CPU_UP_CANCELED:
	case CPU_UP_CANCELED_FROZEN:
	case CPU_DEAD:
	case CPU_DEAD_FROZEN:
		kfree(iucv_param_irq[cpu]);
		iucv_param_irq[cpu] = NULL;
		kfree(iucv_param[cpu]);
		iucv_param[cpu] = NULL;
		kfree(iucv_irq_data[cpu]);
		iucv_irq_data[cpu] = NULL;
		break;
	case CPU_ONLINE:
	case CPU_ONLINE_FROZEN:
	case CPU_DOWN_FAILED:
	case CPU_DOWN_FAILED_FROZEN:
		if (!iucv_path_table)
			break;
		smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
		break;
	case CPU_DOWN_PREPARE:
	case CPU_DOWN_PREPARE_FROZEN:
		if (!iucv_path_table)
			break;
		cpumask_copy(&cpumask, &iucv_buffer_cpumask);
		cpumask_clear_cpu(cpu, &cpumask);
		if (cpumask_empty(&cpumask))
			/* Can't offline last IUCV enabled cpu. */
			return notifier_from_errno(-EINVAL);
		smp_call_function_single(cpu, iucv_retrieve_cpu, NULL, 1);
		if (cpumask_empty(&iucv_irq_cpumask))
			smp_call_function_single(
				cpumask_first(&iucv_buffer_cpumask),
				iucv_allow_cpu, NULL, 1);
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block __refdata iucv_cpu_notifier = {
	.notifier_call = iucv_cpu_notify,
};

/**
 * iucv_sever_pathid
 * @pathid: path identification number.
 * @userdata: 16-bytes of user data.
 *
 * Sever an iucv path to free up the pathid. Used internally.
 */
static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
{
	union iucv_param *parm;

	parm = iucv_param_irq[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (userdata)
		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
	parm->ctrl.ippathid = pathid;
	return iucv_call_b2f0(IUCV_SEVER, parm);
}

/**
 * __iucv_cleanup_queue
 * @dummy: unused dummy argument
 *
 * Nop function called via smp_call_function to force work items from
 * pending external iucv interrupts to the work queue.
 */
static void __iucv_cleanup_queue(void *dummy)
{
}

/**
 * iucv_cleanup_queue
 *
 * Function called after a path has been severed to find all remaining
 * work items for the now stale pathid. The caller needs to hold the
 * iucv_table_lock.
 */
static void iucv_cleanup_queue(void)
{
	struct iucv_irq_list *p, *n;

	/*
	 * When a path is severed, the pathid can be reused immediately
	 * on a iucv connect or a connection pending interrupt. Remove
	 * all entries from the task queue that refer to a stale pathid
	 * (iucv_path_table[ix] == NULL). Only then do the iucv connect
	 * or deliver the connection pending interrupt. To get all the
	 * pending interrupts force them to the work queue by calling
	 * an empty function on all cpus.
	 */
	smp_call_function(__iucv_cleanup_queue, NULL, 1);
	spin_lock_irq(&iucv_queue_lock);
	list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
		/* Remove stale work items from the task queue. */
		if (iucv_path_table[p->data.ippathid] == NULL) {
			list_del(&p->list);
			kfree(p);
		}
	}
	spin_unlock_irq(&iucv_queue_lock);
}

/**
 * iucv_register:
 * @handler: address of iucv handler structure
 * @smp: != 0 indicates that the handler can deal with out of order messages
 *
 * Registers a driver with IUCV.
 *
 * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 */
int iucv_register(struct iucv_handler *handler, int smp)
{
	int rc;

	if (!iucv_available)
		return -ENOSYS;
	mutex_lock(&iucv_register_mutex);
	if (!smp)
		iucv_nonsmp_handler++;
	if (list_empty(&iucv_handler_list)) {
		rc = iucv_enable();
		if (rc)
			goto out_mutex;
	} else if (!smp && iucv_nonsmp_handler == 1)
		iucv_setmask_up();
	INIT_LIST_HEAD(&handler->paths);

	spin_lock_bh(&iucv_table_lock);
	list_add_tail(&handler->list, &iucv_handler_list);
	spin_unlock_bh(&iucv_table_lock);
	rc = 0;
out_mutex:
	mutex_unlock(&iucv_register_mutex);
	return rc;
}
EXPORT_SYMBOL(iucv_register);

/**
 * iucv_unregister
 * @handler:  address of iucv handler structure
 * @smp: != 0 indicates that the handler can deal with out of order messages
 *
 * Unregister driver from IUCV.
 */
void iucv_unregister(struct iucv_handler *handler, int smp)
{
	struct iucv_path *p, *n;

	mutex_lock(&iucv_register_mutex);
	spin_lock_bh(&iucv_table_lock);
	/* Remove handler from the iucv_handler_list. */
	list_del_init(&handler->list);
	/* Sever all pathids still referring to the handler. */
	list_for_each_entry_safe(p, n, &handler->paths, list) {
		iucv_sever_pathid(p->pathid, NULL);
		iucv_path_table[p->pathid] = NULL;
		list_del(&p->list);
		iucv_path_free(p);
	}
	spin_unlock_bh(&iucv_table_lock);
	if (!smp)
		iucv_nonsmp_handler--;
	if (list_empty(&iucv_handler_list))
		iucv_disable();
	else if (!smp && iucv_nonsmp_handler == 0)
		iucv_setmask_mp();
	mutex_unlock(&iucv_register_mutex);
}
EXPORT_SYMBOL(iucv_unregister);

static int iucv_reboot_event(struct notifier_block *this,
			     unsigned long event, void *ptr)
{
	int i;

	get_online_cpus();
	on_each_cpu(iucv_block_cpu, NULL, 1);
	preempt_disable();
	for (i = 0; i < iucv_max_pathid; i++) {
		if (iucv_path_table[i])
			iucv_sever_pathid(i, NULL);
	}
	preempt_enable();
	put_online_cpus();
	iucv_disable();
	return NOTIFY_DONE;
}

static struct notifier_block iucv_reboot_notifier = {
	.notifier_call = iucv_reboot_event,
};

/**
 * iucv_path_accept
 * @path: address of iucv path structure
 * @handler: address of iucv handler structure
 * @userdata: 16 bytes of data reflected to the communication partner
 * @private: private data passed to interrupt handlers for this path
 *
 * This function is issued after the user received a connection pending
 * external interrupt and now wishes to complete the IUCV communication path.
 *
 * Returns the result of the CP IUCV call.
 */
int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
		     u8 userdata[16], void *private)
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	/* Prepare parameter block. */
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	parm->ctrl.ippathid = path->pathid;
	parm->ctrl.ipmsglim = path->msglim;
	if (userdata)
		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
	parm->ctrl.ipflags1 = path->flags;

	rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
	if (!rc) {
		path->private = private;
		path->msglim = parm->ctrl.ipmsglim;
		path->flags = parm->ctrl.ipflags1;
	}
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_path_accept);

/**
 * iucv_path_connect
 * @path: address of iucv path structure
 * @handler: address of iucv handler structure
 * @userid: 8-byte user identification
 * @system: 8-byte target system identification
 * @userdata: 16 bytes of data reflected to the communication partner
 * @private: private data passed to interrupt handlers for this path
 *
 * 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 the result of the CP IUCV call.
 */
int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
		      u8 userid[8], u8 system[8], u8 userdata[16],
		      void *private)
{
	union iucv_param *parm;
	int rc;

	spin_lock_bh(&iucv_table_lock);
	iucv_cleanup_queue();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	parm->ctrl.ipmsglim = path->msglim;
	parm->ctrl.ipflags1 = path->flags;
	if (userid) {
		memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
		ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
		EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
	}
	if (system) {
		memcpy(parm->ctrl.iptarget, system,
		       sizeof(parm->ctrl.iptarget));
		ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
		EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
	}
	if (userdata)
		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));

	rc = iucv_call_b2f0(IUCV_CONNECT, parm);
	if (!rc) {
		if (parm->ctrl.ippathid < iucv_max_pathid) {
			path->pathid = parm->ctrl.ippathid;
			path->msglim = parm->ctrl.ipmsglim;
			path->flags = parm->ctrl.ipflags1;
			path->handler = handler;
			path->private = private;
			list_add_tail(&path->list, &handler->paths);
			iucv_path_table[path->pathid] = path;
		} else {
			iucv_sever_pathid(parm->ctrl.ippathid,
					  iucv_error_pathid);
			rc = -EIO;
		}
	}
out:
	spin_unlock_bh(&iucv_table_lock);
	return rc;
}
EXPORT_SYMBOL(iucv_path_connect);

/**
 * iucv_path_quiesce:
 * @path: address of iucv path structure
 * @userdata: 16 bytes of data reflected to the communication partner
 *
 * This function temporarily suspends incoming messages on an IUCV path.
 * You can later reactivate the path by invoking the iucv_resume function.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (userdata)
		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
	parm->ctrl.ippathid = path->pathid;
	rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_path_quiesce);

/**
 * iucv_path_resume:
 * @path: address of iucv path structure
 * @userdata: 16 bytes of data reflected to the communication partner
 *
 * This function resumes incoming messages on an IUCV path that has
 * been stopped with iucv_path_quiesce.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (userdata)
		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
	parm->ctrl.ippathid = path->pathid;
	rc = iucv_call_b2f0(IUCV_RESUME, parm);
out:
	local_bh_enable();
	return rc;
}

/**
 * iucv_path_sever
 * @path: address of iucv path structure
 * @userdata: 16 bytes of data reflected to the communication partner
 *
 * This function terminates an IUCV path.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
{
	int rc;

	preempt_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	if (iucv_active_cpu != smp_processor_id())
		spin_lock_bh(&iucv_table_lock);
	rc = iucv_sever_pathid(path->pathid, userdata);
	iucv_path_table[path->pathid] = NULL;
	list_del_init(&path->list);
	if (iucv_active_cpu != smp_processor_id())
		spin_unlock_bh(&iucv_table_lock);
out:
	preempt_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_path_sever);

/**
 * iucv_message_purge
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @srccls: source class of message
 *
 * Cancels a message you have sent.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
		       u32 srccls)
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	parm->purge.ippathid = path->pathid;
	parm->purge.ipmsgid = msg->id;
	parm->purge.ipsrccls = srccls;
	parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
	rc = iucv_call_b2f0(IUCV_PURGE, parm);
	if (!rc) {
		msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
		msg->tag = parm->purge.ipmsgtag;
	}
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_purge);

/**
 * iucv_message_receive_iprmdata
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is received (IUCV_IPBUFLST)
 * @buffer: address of data buffer or address of struct iucv_array
 * @size: length of data buffer
 * @residual:
 *
 * Internal function used by iucv_message_receive and __iucv_message_receive
 * to receive RMDATA data stored in struct iucv_message.
 */
static int iucv_message_receive_iprmdata(struct iucv_path *path,
					 struct iucv_message *msg,
					 u8 flags, void *buffer,
					 size_t size, size_t *residual)
{
	struct iucv_array *array;
	u8 *rmmsg;
	size_t copy;

	/*
	 * Message is 8 bytes long and has been stored to the
	 * message descriptor itself.
	 */
	if (residual)
		*residual = abs(size - 8);
	rmmsg = msg->rmmsg;
	if (flags & IUCV_IPBUFLST) {
		/* Copy to struct iucv_array. */
		size = (size < 8) ? size : 8;
		for (array = buffer; size > 0; array++) {
			copy = min_t(size_t, size, array->length);
			memcpy((u8 *)(addr_t) array->address,
				rmmsg, copy);
			rmmsg += copy;
			size -= copy;
		}
	} else {
		/* Copy to direct buffer. */
		memcpy(buffer, rmmsg, min_t(size_t, size, 8));
	}
	return 0;
}

/**
 * __iucv_message_receive
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is received (IUCV_IPBUFLST)
 * @buffer: address of data buffer or address of struct iucv_array
 * @size: length of data buffer
 * @residual:
 *
 * This function receives messages that are being sent to you over
 * established paths. This function will deal with RMDATA messages
 * embedded in struct iucv_message as well.
 *
 * Locking:	no locking
 *
 * Returns the result from the CP IUCV call.
 */
int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
			   u8 flags, void *buffer, size_t size, size_t *residual)
{
	union iucv_param *parm;
	int rc;

	if (msg->flags & IUCV_IPRMDATA)
		return iucv_message_receive_iprmdata(path, msg, flags,
						     buffer, size, residual);
	 if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	parm->db.ipbfadr1 = (u32)(addr_t) buffer;
	parm->db.ipbfln1f = (u32) size;
	parm->db.ipmsgid = msg->id;
	parm->db.ippathid = path->pathid;
	parm->db.iptrgcls = msg->class;
	parm->db.ipflags1 = (flags | IUCV_IPFGPID |
			     IUCV_IPFGMID | IUCV_IPTRGCLS);
	rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
	if (!rc || rc == 5) {
		msg->flags = parm->db.ipflags1;
		if (residual)
			*residual = parm->db.ipbfln1f;
	}
out:
	return rc;
}
EXPORT_SYMBOL(__iucv_message_receive);

/**
 * iucv_message_receive
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is received (IUCV_IPBUFLST)
 * @buffer: address of data buffer or address of struct iucv_array
 * @size: length of data buffer
 * @residual:
 *
 * This function receives messages that are being sent to you over
 * established paths. This function will deal with RMDATA messages
 * embedded in struct iucv_message as well.
 *
 * Locking:	local_bh_enable/local_bh_disable
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
			 u8 flags, void *buffer, size_t size, size_t *residual)
{
	int rc;

	if (msg->flags & IUCV_IPRMDATA)
		return iucv_message_receive_iprmdata(path, msg, flags,
						     buffer, size, residual);
	local_bh_disable();
	rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_receive);

/**
 * iucv_message_reject
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 *
 * The reject function 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.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	parm->db.ippathid = path->pathid;
	parm->db.ipmsgid = msg->id;
	parm->db.iptrgcls = msg->class;
	parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
	rc = iucv_call_b2f0(IUCV_REJECT, parm);
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_reject);

/**
 * iucv_message_reply
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
 * @reply: address of reply data buffer or address of struct iucv_array
 * @size: length of reply data buffer
 *
 * 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.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
		       u8 flags, void *reply, size_t size)
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (flags & IUCV_IPRMDATA) {
		parm->dpl.ippathid = path->pathid;
		parm->dpl.ipflags1 = flags;
		parm->dpl.ipmsgid = msg->id;
		parm->dpl.iptrgcls = msg->class;
		memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
	} else {
		parm->db.ipbfadr1 = (u32)(addr_t) reply;
		parm->db.ipbfln1f = (u32) size;
		parm->db.ippathid = path->pathid;
		parm->db.ipflags1 = flags;
		parm->db.ipmsgid = msg->id;
		parm->db.iptrgcls = msg->class;
	}
	rc = iucv_call_b2f0(IUCV_REPLY, parm);
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_reply);

/**
 * __iucv_message_send
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
 * @srccls: source class of message
 * @buffer: address of send buffer or address of struct iucv_array
 * @size: length of send buffer
 *
 * This function transmits data to another application. Data to be
 * transmitted is in a buffer and this is a one-way message and the
 * receiver will not reply to the message.
 *
 * Locking:	no locking
 *
 * Returns the result from the CP IUCV call.
 */
int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
		      u8 flags, u32 srccls, void *buffer, size_t size)
{
	union iucv_param *parm;
	int rc;

	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (flags & IUCV_IPRMDATA) {
		/* Message of 8 bytes can be placed into the parameter list. */
		parm->dpl.ippathid = path->pathid;
		parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
		parm->dpl.iptrgcls = msg->class;
		parm->dpl.ipsrccls = srccls;
		parm->dpl.ipmsgtag = msg->tag;
		memcpy(parm->dpl.iprmmsg, buffer, 8);
	} else {
		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
		parm->db.ipbfln1f = (u32) size;
		parm->db.ippathid = path->pathid;
		parm->db.ipflags1 = flags | IUCV_IPNORPY;
		parm->db.iptrgcls = msg->class;
		parm->db.ipsrccls = srccls;
		parm->db.ipmsgtag = msg->tag;
	}
	rc = iucv_call_b2f0(IUCV_SEND, parm);
	if (!rc)
		msg->id = parm->db.ipmsgid;
out:
	return rc;
}
EXPORT_SYMBOL(__iucv_message_send);

/**
 * iucv_message_send
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
 * @srccls: source class of message
 * @buffer: address of send buffer or address of struct iucv_array
 * @size: length of send buffer
 *
 * This function transmits data to another application. Data to be
 * transmitted is in a buffer and this is a one-way message and the
 * receiver will not reply to the message.
 *
 * Locking:	local_bh_enable/local_bh_disable
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
		      u8 flags, u32 srccls, void *buffer, size_t size)
{
	int rc;

	local_bh_disable();
	rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_send);

/**
 * iucv_message_send2way
 * @path: address of iucv path structure
 * @msg: address of iucv msg structure
 * @flags: how the message is sent and the reply is received
 *	   (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
 * @srccls: source class of message
 * @buffer: address of send buffer or address of struct iucv_array
 * @size: length of send buffer
 * @ansbuf: address of answer buffer or address of struct iucv_array
 * @asize: size of reply buffer
 *
 * 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.
 *
 * Returns the result from the CP IUCV call.
 */
int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
			  u8 flags, u32 srccls, void *buffer, size_t size,
			  void *answer, size_t asize, size_t *residual)
{
	union iucv_param *parm;
	int rc;

	local_bh_disable();
	if (cpumask_empty(&iucv_buffer_cpumask)) {
		rc = -EIO;
		goto out;
	}
	parm = iucv_param[smp_processor_id()];
	memset(parm, 0, sizeof(union iucv_param));
	if (flags & IUCV_IPRMDATA) {
		parm->dpl.ippathid = path->pathid;
		parm->dpl.ipflags1 = path->flags;	/* priority message */
		parm->dpl.iptrgcls = msg->class;
		parm->dpl.ipsrccls = srccls;
		parm->dpl.ipmsgtag = msg->tag;
		parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
		parm->dpl.ipbfln2f = (u32) asize;
		memcpy(parm->dpl.iprmmsg, buffer, 8);
	} else {
		parm->db.ippathid = path->pathid;
		parm->db.ipflags1 = path->flags;	/* priority message */
		parm->db.iptrgcls = msg->class;
		parm->db.ipsrccls = srccls;
		parm->db.ipmsgtag = msg->tag;
		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
		parm->db.ipbfln1f = (u32) size;
		parm->db.ipbfadr2 = (u32)(addr_t) answer;
		parm->db.ipbfln2f = (u32) asize;
	}
	rc = iucv_call_b2f0(IUCV_SEND, parm);
	if (!rc)
		msg->id = parm->db.ipmsgid;
out:
	local_bh_enable();
	return rc;
}
EXPORT_SYMBOL(iucv_message_send2way);

/**
 * iucv_path_pending
 * @data: Pointer to external interrupt buffer
 *
 * Process connection pending work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_path_pending {
	u16 ippathid;
	u8  ipflags1;
	u8  iptype;
	u16 ipmsglim;
	u16 res1;
	u8  ipvmid[8];
	u8  ipuser[16];
	u32 res3;
	u8  ippollfg;
	u8  res4[3];
} __packed;

static void iucv_path_pending(struct iucv_irq_data *data)
{
	struct iucv_path_pending *ipp = (void *) data;
	struct iucv_handler *handler;
	struct iucv_path *path;
	char *error;

	BUG_ON(iucv_path_table[ipp->ippathid]);
	/* New pathid, handler found. Create a new path struct. */
	error = iucv_error_no_memory;
	path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
	if (!path)
		goto out_sever;
	path->pathid = ipp->ippathid;
	iucv_path_table[path->pathid] = path;
	EBCASC(ipp->ipvmid, 8);

	/* Call registered handler until one is found that wants the path. */
	list_for_each_entry(handler, &iucv_handler_list, list) {
		if (!handler->path_pending)
			continue;
		/*
		 * Add path to handler to allow a call to iucv_path_sever
		 * inside the path_pending function. If the handler returns
		 * an error remove the path from the handler again.
		 */
		list_add(&path->list, &handler->paths);
		path->handler = handler;
		if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
			return;
		list_del(&path->list);
		path->handler = NULL;
	}
	/* No handler wanted the path. */
	iucv_path_table[path->pathid] = NULL;
	iucv_path_free(path);
	error = iucv_error_no_listener;
out_sever:
	iucv_sever_pathid(ipp->ippathid, error);
}

/**
 * iucv_path_complete
 * @data: Pointer to external interrupt buffer
 *
 * Process connection complete work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_path_complete {
	u16 ippathid;
	u8  ipflags1;
	u8  iptype;
	u16 ipmsglim;
	u16 res1;
	u8  res2[8];
	u8  ipuser[16];
	u32 res3;
	u8  ippollfg;
	u8  res4[3];
} __packed;

static void iucv_path_complete(struct iucv_irq_data *data)
{
	struct iucv_path_complete *ipc = (void *) data;
	struct iucv_path *path = iucv_path_table[ipc->ippathid];

	if (path)
		path->flags = ipc->ipflags1;
	if (path && path->handler && path->handler->path_complete)
		path->handler->path_complete(path, ipc->ipuser);
}

/**
 * iucv_path_severed
 * @data: Pointer to external interrupt buffer
 *
 * Process connection severed work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_path_severed {
	u16 ippathid;
	u8  res1;
	u8  iptype;
	u32 res2;
	u8  res3[8];
	u8  ipuser[16];
	u32 res4;
	u8  ippollfg;
	u8  res5[3];
} __packed;

static void iucv_path_severed(struct iucv_irq_data *data)
{
	struct iucv_path_severed *ips = (void *) data;
	struct iucv_path *path = iucv_path_table[ips->ippathid];

	if (!path || !path->handler)	/* Already severed */
		return;
	if (path->handler->path_severed)
		path->handler->path_severed(path, ips->ipuser);
	else {
		iucv_sever_pathid(path->pathid, NULL);
		iucv_path_table[path->pathid] = NULL;
		list_del(&path->list);
		iucv_path_free(path);
	}
}

/**
 * iucv_path_quiesced
 * @data: Pointer to external interrupt buffer
 *
 * Process connection quiesced work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_path_quiesced {
	u16 ippathid;
	u8  res1;
	u8  iptype;
	u32 res2;
	u8  res3[8];
	u8  ipuser[16];
	u32 res4;
	u8  ippollfg;
	u8  res5[3];
} __packed;

static void iucv_path_quiesced(struct iucv_irq_data *data)
{
	struct iucv_path_quiesced *ipq = (void *) data;
	struct iucv_path *path = iucv_path_table[ipq->ippathid];

	if (path && path->handler && path->handler->path_quiesced)
		path->handler->path_quiesced(path, ipq->ipuser);
}

/**
 * iucv_path_resumed
 * @data: Pointer to external interrupt buffer
 *
 * Process connection resumed work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_path_resumed {
	u16 ippathid;
	u8  res1;
	u8  iptype;
	u32 res2;
	u8  res3[8];
	u8  ipuser[16];
	u32 res4;
	u8  ippollfg;
	u8  res5[3];
} __packed;

static void iucv_path_resumed(struct iucv_irq_data *data)
{
	struct iucv_path_resumed *ipr = (void *) data;
	struct iucv_path *path = iucv_path_table[ipr->ippathid];

	if (path && path->handler && path->handler->path_resumed)
		path->handler->path_resumed(path, ipr->ipuser);
}

/**
 * iucv_message_complete
 * @data: Pointer to external interrupt buffer
 *
 * Process message complete work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_message_complete {
	u16 ippathid;
	u8  ipflags1;
	u8  iptype;
	u32 ipmsgid;
	u32 ipaudit;
	u8  iprmmsg[8];
	u32 ipsrccls;
	u32 ipmsgtag;
	u32 res;
	u32 ipbfln2f;
	u8  ippollfg;
	u8  res2[3];
} __packed;

static void iucv_message_complete(struct iucv_irq_data *data)
{
	struct iucv_message_complete *imc = (void *) data;
	struct iucv_path *path = iucv_path_table[imc->ippathid];
	struct iucv_message msg;

	if (path && path->handler && path->handler->message_complete) {
		msg.flags = imc->ipflags1;
		msg.id = imc->ipmsgid;
		msg.audit = imc->ipaudit;
		memcpy(msg.rmmsg, imc->iprmmsg, 8);
		msg.class = imc->ipsrccls;
		msg.tag = imc->ipmsgtag;
		msg.length = imc->ipbfln2f;
		path->handler->message_complete(path, &msg);
	}
}

/**
 * iucv_message_pending
 * @data: Pointer to external interrupt buffer
 *
 * Process message pending work item. Called from tasklet while holding
 * iucv_table_lock.
 */
struct iucv_message_pending {
	u16 ippathid;
	u8  ipflags1;
	u8  iptype;
	u32 ipmsgid;
	u32 iptrgcls;
	union {
		u32 iprmmsg1_u32;
		u8  iprmmsg1[4];
	} ln1msg1;
	union {
		u32 ipbfln1f;
		u8  iprmmsg2[4];
	} ln1msg2;
	u32 res1[3];
	u32 ipbfln2f;
	u8  ippollfg;
	u8  res2[3];
} __packed;

static void iucv_message_pending(struct iucv_irq_data *data)
{
	struct iucv_message_pending *imp = (void *) data;
	struct iucv_path *path = iucv_path_table[imp->ippathid];
	struct iucv_message msg;

	if (path && path->handler && path->handler->message_pending) {
		msg.flags = imp->ipflags1;
		msg.id = imp->ipmsgid;
		msg.class = imp->iptrgcls;
		if (imp->ipflags1 & IUCV_IPRMDATA) {
			memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
			msg.length = 8;
		} else
			msg.length = imp->ln1msg2.ipbfln1f;
		msg.reply_size = imp->ipbfln2f;
		path->handler->message_pending(path, &msg);
	}
}

/**
 * iucv_tasklet_fn:
 *
 * This tasklet loops over the queue of irq buffers created by
 * iucv_external_interrupt, calls the appropriate action handler
 * and then frees the buffer.
 */
static void iucv_tasklet_fn(unsigned long ignored)
{
	typedef void iucv_irq_fn(struct iucv_irq_data *);
	static iucv_irq_fn *irq_fn[] = {
		[0x02] = iucv_path_complete,
		[0x03] = iucv_path_severed,
		[0x04] = iucv_path_quiesced,
		[0x05] = iucv_path_resumed,
		[0x06] = iucv_message_complete,
		[0x07] = iucv_message_complete,
		[0x08] = iucv_message_pending,
		[0x09] = iucv_message_pending,
	};
	LIST_HEAD(task_queue);
	struct iucv_irq_list *p, *n;

	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
	if (!spin_trylock(&iucv_table_lock)) {
		tasklet_schedule(&iucv_tasklet);
		return;
	}
	iucv_active_cpu = smp_processor_id();

	spin_lock_irq(&iucv_queue_lock);
	list_splice_init(&iucv_task_queue, &task_queue);
	spin_unlock_irq(&iucv_queue_lock);

	list_for_each_entry_safe(p, n, &task_queue, list) {
		list_del_init(&p->list);
		irq_fn[p->data.iptype](&p->data);
		kfree(p);
	}

	iucv_active_cpu = -1;
	spin_unlock(&iucv_table_lock);
}

/**
 * iucv_work_fn:
 *
 * This work function loops over the queue of path pending irq blocks
 * created by iucv_external_interrupt, calls the appropriate action
 * handler and then frees the buffer.
 */
static void iucv_work_fn(struct work_struct *work)
{
	LIST_HEAD(work_queue);
	struct iucv_irq_list *p, *n;

	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
	spin_lock_bh(&iucv_table_lock);
	iucv_active_cpu = smp_processor_id();

	spin_lock_irq(&iucv_queue_lock);
	list_splice_init(&iucv_work_queue, &work_queue);
	spin_unlock_irq(&iucv_queue_lock);

	iucv_cleanup_queue();
	list_for_each_entry_safe(p, n, &work_queue, list) {
		list_del_init(&p->list);
		iucv_path_pending(&p->data);
		kfree(p);
	}

	iucv_active_cpu = -1;
	spin_unlock_bh(&iucv_table_lock);
}

/**
 * iucv_external_interrupt
 * @code: irq code
 *
 * Handles external interrupts coming in from CP.
 * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
 */
static void iucv_external_interrupt(struct ext_code ext_code,
				    unsigned int param32, unsigned long param64)
{
	struct iucv_irq_data *p;
	struct iucv_irq_list *work;

	kstat_cpu(smp_processor_id()).irqs[EXTINT_IUC]++;
	p = iucv_irq_data[smp_processor_id()];
	if (p->ippathid >= iucv_max_pathid) {
		WARN_ON(p->ippathid >= iucv_max_pathid);
		iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
		return;
	}
	BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
	work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
	if (!work) {
		pr_warning("iucv_external_interrupt: out of memory\n");
		return;
	}
	memcpy(&work->data, p, sizeof(work->data));
	spin_lock(&iucv_queue_lock);
	if (p->iptype == 0x01) {
		/* Path pending interrupt. */
		list_add_tail(&work->list, &iucv_work_queue);
		schedule_work(&iucv_work);
	} else {
		/* The other interrupts. */
		list_add_tail(&work->list, &iucv_task_queue);
		tasklet_schedule(&iucv_tasklet);
	}
	spin_unlock(&iucv_queue_lock);
}

static int iucv_pm_prepare(struct device *dev)
{
	int rc = 0;

#ifdef CONFIG_PM_DEBUG
	printk(KERN_INFO "iucv_pm_prepare\n");
#endif
	if (dev->driver && dev->driver->pm && dev->driver->pm->prepare)
		rc = dev->driver->pm->prepare(dev);
	return rc;
}

static void iucv_pm_complete(struct device *dev)
{
#ifdef CONFIG_PM_DEBUG
	printk(KERN_INFO "iucv_pm_complete\n");
#endif
	if (dev->driver && dev->driver->pm && dev->driver->pm->complete)
		dev->driver->pm->complete(dev);
}

/**
 * iucv_path_table_empty() - determine if iucv path table is empty
 *
 * Returns 0 if there are still iucv pathes defined
 *	   1 if there are no iucv pathes defined
 */
int iucv_path_table_empty(void)
{
	int i;

	for (i = 0; i < iucv_max_pathid; i++) {
		if (iucv_path_table[i])
			return 0;
	}
	return 1;
}

/**
 * iucv_pm_freeze() - Freeze PM callback
 * @dev:	iucv-based device
 *
 * disable iucv interrupts
 * invoke callback function of the iucv-based driver
 * shut down iucv, if no iucv-pathes are established anymore
 */
static int iucv_pm_freeze(struct device *dev)
{
	int cpu;
	struct iucv_irq_list *p, *n;
	int rc = 0;

#ifdef CONFIG_PM_DEBUG
	printk(KERN_WARNING "iucv_pm_freeze\n");
#endif
	if (iucv_pm_state != IUCV_PM_FREEZING) {
		for_each_cpu(cpu, &iucv_irq_cpumask)
			smp_call_function_single(cpu, iucv_block_cpu_almost,
						 NULL, 1);
		cancel_work_sync(&iucv_work);
		list_for_each_entry_safe(p, n, &iucv_work_queue, list) {
			list_del_init(&p->list);
			iucv_sever_pathid(p->data.ippathid,
					  iucv_error_no_listener);
			kfree(p);
		}
	}
	iucv_pm_state = IUCV_PM_FREEZING;
	if (dev->driver && dev->driver->pm && dev->driver->pm->freeze)
		rc = dev->driver->pm->freeze(dev);
	if (iucv_path_table_empty())
		iucv_disable();
	return rc;
}

/**
 * iucv_pm_thaw() - Thaw PM callback
 * @dev:	iucv-based device
 *
 * make iucv ready for use again: allocate path table, declare interrupt buffers
 *				  and enable iucv interrupts
 * invoke callback function of the iucv-based driver
 */
static int iucv_pm_thaw(struct device *dev)
{
	int rc = 0;

#ifdef CONFIG_PM_DEBUG
	printk(KERN_WARNING "iucv_pm_thaw\n");
#endif
	iucv_pm_state = IUCV_PM_THAWING;
	if (!iucv_path_table) {
		rc = iucv_enable();
		if (rc)
			goto out;
	}
	if (cpumask_empty(&iucv_irq_cpumask)) {
		if (iucv_nonsmp_handler)
			/* enable interrupts on one cpu */
			iucv_allow_cpu(NULL);
		else
			/* enable interrupts on all cpus */
			iucv_setmask_mp();
	}
	if (dev->driver && dev->driver->pm && dev->driver->pm->thaw)
		rc = dev->driver->pm->thaw(dev);
out:
	return rc;
}

/**
 * iucv_pm_restore() - Restore PM callback
 * @dev:	iucv-based device
 *
 * make iucv ready for use again: allocate path table, declare interrupt buffers
 *				  and enable iucv interrupts
 * invoke callback function of the iucv-based driver
 */
static int iucv_pm_restore(struct device *dev)
{
	int rc = 0;

#ifdef CONFIG_PM_DEBUG
	printk(KERN_WARNING "iucv_pm_restore %p\n", iucv_path_table);
#endif
	if ((iucv_pm_state != IUCV_PM_RESTORING) && iucv_path_table)
		pr_warning("Suspending Linux did not completely close all IUCV "
			"connections\n");
	iucv_pm_state = IUCV_PM_RESTORING;
	if (cpumask_empty(&iucv_irq_cpumask)) {
		rc = iucv_query_maxconn();
		rc = iucv_enable();
		if (rc)
			goto out;
	}
	if (dev->driver && dev->driver->pm && dev->driver->pm->restore)
		rc = dev->driver->pm->restore(dev);
out:
	return rc;
}

struct iucv_interface iucv_if = {
	.message_receive = iucv_message_receive,
	.__message_receive = __iucv_message_receive,
	.message_reply = iucv_message_reply,
	.message_reject = iucv_message_reject,
	.message_send = iucv_message_send,
	.__message_send = __iucv_message_send,
	.message_send2way = iucv_message_send2way,
	.message_purge = iucv_message_purge,
	.path_accept = iucv_path_accept,
	.path_connect = iucv_path_connect,
	.path_quiesce = iucv_path_quiesce,
	.path_resume = iucv_path_resume,
	.path_sever = iucv_path_sever,
	.iucv_register = iucv_register,
	.iucv_unregister = iucv_unregister,
	.bus = NULL,
	.root = NULL,
};
EXPORT_SYMBOL(iucv_if);

/**
 * iucv_init
 *
 * Allocates and initializes various data structures.
 */
static int __init iucv_init(void)
{
	int rc;
	int cpu;

	if (!MACHINE_IS_VM) {
		rc = -EPROTONOSUPPORT;
		goto out;
	}
	ctl_set_bit(0, 1);
	rc = iucv_query_maxconn();
	if (rc)
		goto out_ctl;
	rc = register_external_interrupt(0x4000, iucv_external_interrupt);
	if (rc)
		goto out_ctl;
	iucv_root = root_device_register("iucv");
	if (IS_ERR(iucv_root)) {
		rc = PTR_ERR(iucv_root);
		goto out_int;
	}

	for_each_online_cpu(cpu) {
		/* Note: GFP_DMA used to get memory below 2G */
		iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
				     GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_irq_data[cpu]) {
			rc = -ENOMEM;
			goto out_free;
		}

		/* Allocate parameter blocks. */
		iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
				  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_param[cpu]) {
			rc = -ENOMEM;
			goto out_free;
		}
		iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
				  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
		if (!iucv_param_irq[cpu]) {
			rc = -ENOMEM;
			goto out_free;
		}

	}
	rc = register_hotcpu_notifier(&iucv_cpu_notifier);
	if (rc)
		goto out_free;
	rc = register_reboot_notifier(&iucv_reboot_notifier);
	if (rc)
		goto out_cpu;
	ASCEBC(iucv_error_no_listener, 16);
	ASCEBC(iucv_error_no_memory, 16);
	ASCEBC(iucv_error_pathid, 16);
	iucv_available = 1;
	rc = bus_register(&iucv_bus);
	if (rc)
		goto out_reboot;
	iucv_if.root = iucv_root;
	iucv_if.bus = &iucv_bus;
	return 0;

out_reboot:
	unregister_reboot_notifier(&iucv_reboot_notifier);
out_cpu:
	unregister_hotcpu_notifier(&iucv_cpu_notifier);
out_free:
	for_each_possible_cpu(cpu) {
		kfree(iucv_param_irq[cpu]);
		iucv_param_irq[cpu] = NULL;
		kfree(iucv_param[cpu]);
		iucv_param[cpu] = NULL;
		kfree(iucv_irq_data[cpu]);
		iucv_irq_data[cpu] = NULL;
	}
	root_device_unregister(iucv_root);
out_int:
	unregister_external_interrupt(0x4000, iucv_external_interrupt);
out_ctl:
	ctl_clear_bit(0, 1);
out:
	return rc;
}

/**
 * iucv_exit
 *
 * Frees everything allocated from iucv_init.
 */
static void __exit iucv_exit(void)
{
	struct iucv_irq_list *p, *n;
	int cpu;

	spin_lock_irq(&iucv_queue_lock);
	list_for_each_entry_safe(p, n, &iucv_task_queue, list)
		kfree(p);
	list_for_each_entry_safe(p, n, &iucv_work_queue, list)
		kfree(p);
	spin_unlock_irq(&iucv_queue_lock);
	unregister_reboot_notifier(&iucv_reboot_notifier);
	unregister_hotcpu_notifier(&iucv_cpu_notifier);
	for_each_possible_cpu(cpu) {
		kfree(iucv_param_irq[cpu]);
		iucv_param_irq[cpu] = NULL;
		kfree(iucv_param[cpu]);
		iucv_param[cpu] = NULL;
		kfree(iucv_irq_data[cpu]);
		iucv_irq_data[cpu] = NULL;
	}
	root_device_unregister(iucv_root);
	bus_unregister(&iucv_bus);
	unregister_external_interrupt(0x4000, iucv_external_interrupt);
}

subsys_initcall(iucv_init);
module_exit(iucv_exit);

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