summaryrefslogtreecommitdiff
path: root/drivers/s390/block/dasd_eckd.c
blob: c48c72abbefc640671af73090536bd206b1c95dc (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
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
/*
 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
 *		    Horst Hummel <Horst.Hummel@de.ibm.com>
 *		    Carsten Otte <Cotte@de.ibm.com>
 *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
 * Bugreports.to..: <Linux390@de.ibm.com>
 * Copyright IBM Corp. 1999, 2009
 * EMC Symmetrix ioctl Copyright EMC Corporation, 2008
 * Author.........: Nigel Hislop <hislop_nigel@emc.com>
 */

#define KMSG_COMPONENT "dasd-eckd"

#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/hdreg.h>	/* HDIO_GETGEO			    */
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/compat.h>
#include <linux/init.h>

#include <asm/debug.h>
#include <asm/idals.h>
#include <asm/ebcdic.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/cio.h>
#include <asm/ccwdev.h>
#include <asm/itcw.h>

#include "dasd_int.h"
#include "dasd_eckd.h"
#include "../cio/chsc.h"


#ifdef PRINTK_HEADER
#undef PRINTK_HEADER
#endif				/* PRINTK_HEADER */
#define PRINTK_HEADER "dasd(eckd):"

#define ECKD_C0(i) (i->home_bytes)
#define ECKD_F(i) (i->formula)
#define ECKD_F1(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f1):\
		    (i->factors.f_0x02.f1))
#define ECKD_F2(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f2):\
		    (i->factors.f_0x02.f2))
#define ECKD_F3(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f3):\
		    (i->factors.f_0x02.f3))
#define ECKD_F4(i) (ECKD_F(i)==0x02?(i->factors.f_0x02.f4):0)
#define ECKD_F5(i) (ECKD_F(i)==0x02?(i->factors.f_0x02.f5):0)
#define ECKD_F6(i) (i->factor6)
#define ECKD_F7(i) (i->factor7)
#define ECKD_F8(i) (i->factor8)

/*
 * raw track access always map to 64k in memory
 * so it maps to 16 blocks of 4k per track
 */
#define DASD_RAW_BLOCK_PER_TRACK 16
#define DASD_RAW_BLOCKSIZE 4096
/* 64k are 128 x 512 byte sectors  */
#define DASD_RAW_SECTORS_PER_TRACK 128

MODULE_LICENSE("GPL");

static struct dasd_discipline dasd_eckd_discipline;

/* The ccw bus type uses this table to find devices that it sends to
 * dasd_eckd_probe */
static struct ccw_device_id dasd_eckd_ids[] = {
	{ CCW_DEVICE_DEVTYPE (0x3990, 0, 0x3390, 0), .driver_info = 0x1},
	{ CCW_DEVICE_DEVTYPE (0x2105, 0, 0x3390, 0), .driver_info = 0x2},
	{ CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3380, 0), .driver_info = 0x3},
	{ CCW_DEVICE_DEVTYPE (0x3990, 0, 0x3380, 0), .driver_info = 0x4},
	{ CCW_DEVICE_DEVTYPE (0x2105, 0, 0x3380, 0), .driver_info = 0x5},
	{ CCW_DEVICE_DEVTYPE (0x9343, 0, 0x9345, 0), .driver_info = 0x6},
	{ CCW_DEVICE_DEVTYPE (0x2107, 0, 0x3390, 0), .driver_info = 0x7},
	{ CCW_DEVICE_DEVTYPE (0x2107, 0, 0x3380, 0), .driver_info = 0x8},
	{ CCW_DEVICE_DEVTYPE (0x1750, 0, 0x3390, 0), .driver_info = 0x9},
	{ CCW_DEVICE_DEVTYPE (0x1750, 0, 0x3380, 0), .driver_info = 0xa},
	{ /* end of list */ },
};

MODULE_DEVICE_TABLE(ccw, dasd_eckd_ids);

static struct ccw_driver dasd_eckd_driver; /* see below */

#define INIT_CQR_OK 0
#define INIT_CQR_UNFORMATTED 1
#define INIT_CQR_ERROR 2

/* emergency request for reserve/release */
static struct {
	struct dasd_ccw_req cqr;
	struct ccw1 ccw;
	char data[32];
} *dasd_reserve_req;
static DEFINE_MUTEX(dasd_reserve_mutex);

/* definitions for the path verification worker */
struct path_verification_work_data {
	struct work_struct worker;
	struct dasd_device *device;
	struct dasd_ccw_req cqr;
	struct ccw1 ccw;
	__u8 rcd_buffer[DASD_ECKD_RCD_DATA_SIZE];
	int isglobal;
	__u8 tbvpm;
};
static struct path_verification_work_data *path_verification_worker;
static DEFINE_MUTEX(dasd_path_verification_mutex);

/* initial attempt at a probe function. this can be simplified once
 * the other detection code is gone */
static int
dasd_eckd_probe (struct ccw_device *cdev)
{
	int ret;

	/* set ECKD specific ccw-device options */
	ret = ccw_device_set_options(cdev, CCWDEV_ALLOW_FORCE |
				     CCWDEV_DO_PATHGROUP | CCWDEV_DO_MULTIPATH);
	if (ret) {
		DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
				"dasd_eckd_probe: could not set "
				"ccw-device options");
		return ret;
	}
	ret = dasd_generic_probe(cdev, &dasd_eckd_discipline);
	return ret;
}

static int
dasd_eckd_set_online(struct ccw_device *cdev)
{
	return dasd_generic_set_online(cdev, &dasd_eckd_discipline);
}

static const int sizes_trk0[] = { 28, 148, 84 };
#define LABEL_SIZE 140

static inline unsigned int
round_up_multiple(unsigned int no, unsigned int mult)
{
	int rem = no % mult;
	return (rem ? no - rem + mult : no);
}

static inline unsigned int
ceil_quot(unsigned int d1, unsigned int d2)
{
	return (d1 + (d2 - 1)) / d2;
}

static unsigned int
recs_per_track(struct dasd_eckd_characteristics * rdc,
	       unsigned int kl, unsigned int dl)
{
	int dn, kn;

	switch (rdc->dev_type) {
	case 0x3380:
		if (kl)
			return 1499 / (15 + 7 + ceil_quot(kl + 12, 32) +
				       ceil_quot(dl + 12, 32));
		else
			return 1499 / (15 + ceil_quot(dl + 12, 32));
	case 0x3390:
		dn = ceil_quot(dl + 6, 232) + 1;
		if (kl) {
			kn = ceil_quot(kl + 6, 232) + 1;
			return 1729 / (10 + 9 + ceil_quot(kl + 6 * kn, 34) +
				       9 + ceil_quot(dl + 6 * dn, 34));
		} else
			return 1729 / (10 + 9 + ceil_quot(dl + 6 * dn, 34));
	case 0x9345:
		dn = ceil_quot(dl + 6, 232) + 1;
		if (kl) {
			kn = ceil_quot(kl + 6, 232) + 1;
			return 1420 / (18 + 7 + ceil_quot(kl + 6 * kn, 34) +
				       ceil_quot(dl + 6 * dn, 34));
		} else
			return 1420 / (18 + 7 + ceil_quot(dl + 6 * dn, 34));
	}
	return 0;
}

static void set_ch_t(struct ch_t *geo, __u32 cyl, __u8 head)
{
	geo->cyl = (__u16) cyl;
	geo->head = cyl >> 16;
	geo->head <<= 4;
	geo->head |= head;
}

static int
check_XRC (struct ccw1         *de_ccw,
           struct DE_eckd_data *data,
           struct dasd_device  *device)
{
        struct dasd_eckd_private *private;
	int rc;

        private = (struct dasd_eckd_private *) device->private;
	if (!private->rdc_data.facilities.XRC_supported)
		return 0;

        /* switch on System Time Stamp - needed for XRC Support */
	data->ga_extended |= 0x08; /* switch on 'Time Stamp Valid'   */
	data->ga_extended |= 0x02; /* switch on 'Extended Parameter' */

	rc = get_sync_clock(&data->ep_sys_time);
	/* Ignore return code if sync clock is switched off. */
	if (rc == -ENOSYS || rc == -EACCES)
		rc = 0;

	de_ccw->count = sizeof(struct DE_eckd_data);
	de_ccw->flags |= CCW_FLAG_SLI;
	return rc;
}

static int
define_extent(struct ccw1 *ccw, struct DE_eckd_data *data, unsigned int trk,
	      unsigned int totrk, int cmd, struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	u32 begcyl, endcyl;
	u16 heads, beghead, endhead;
	int rc = 0;

	private = (struct dasd_eckd_private *) device->private;

	ccw->cmd_code = DASD_ECKD_CCW_DEFINE_EXTENT;
	ccw->flags = 0;
	ccw->count = 16;
	ccw->cda = (__u32) __pa(data);

	memset(data, 0, sizeof(struct DE_eckd_data));
	switch (cmd) {
	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
	case DASD_ECKD_CCW_READ_RECORD_ZERO:
	case DASD_ECKD_CCW_READ:
	case DASD_ECKD_CCW_READ_MT:
	case DASD_ECKD_CCW_READ_CKD:
	case DASD_ECKD_CCW_READ_CKD_MT:
	case DASD_ECKD_CCW_READ_KD:
	case DASD_ECKD_CCW_READ_KD_MT:
	case DASD_ECKD_CCW_READ_COUNT:
		data->mask.perm = 0x1;
		data->attributes.operation = private->attrib.operation;
		break;
	case DASD_ECKD_CCW_WRITE:
	case DASD_ECKD_CCW_WRITE_MT:
	case DASD_ECKD_CCW_WRITE_KD:
	case DASD_ECKD_CCW_WRITE_KD_MT:
		data->mask.perm = 0x02;
		data->attributes.operation = private->attrib.operation;
		rc = check_XRC (ccw, data, device);
		break;
	case DASD_ECKD_CCW_WRITE_CKD:
	case DASD_ECKD_CCW_WRITE_CKD_MT:
		data->attributes.operation = DASD_BYPASS_CACHE;
		rc = check_XRC (ccw, data, device);
		break;
	case DASD_ECKD_CCW_ERASE:
	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
		data->mask.perm = 0x3;
		data->mask.auth = 0x1;
		data->attributes.operation = DASD_BYPASS_CACHE;
		rc = check_XRC (ccw, data, device);
		break;
	default:
		dev_err(&device->cdev->dev,
			"0x%x is not a known command\n", cmd);
		break;
	}

	data->attributes.mode = 0x3;	/* ECKD */

	if ((private->rdc_data.cu_type == 0x2105 ||
	     private->rdc_data.cu_type == 0x2107 ||
	     private->rdc_data.cu_type == 0x1750)
	    && !(private->uses_cdl && trk < 2))
		data->ga_extended |= 0x40; /* Regular Data Format Mode */

	heads = private->rdc_data.trk_per_cyl;
	begcyl = trk / heads;
	beghead = trk % heads;
	endcyl = totrk / heads;
	endhead = totrk % heads;

	/* check for sequential prestage - enhance cylinder range */
	if (data->attributes.operation == DASD_SEQ_PRESTAGE ||
	    data->attributes.operation == DASD_SEQ_ACCESS) {

		if (endcyl + private->attrib.nr_cyl < private->real_cyl)
			endcyl += private->attrib.nr_cyl;
		else
			endcyl = (private->real_cyl - 1);
	}

	set_ch_t(&data->beg_ext, begcyl, beghead);
	set_ch_t(&data->end_ext, endcyl, endhead);
	return rc;
}

static int check_XRC_on_prefix(struct PFX_eckd_data *pfxdata,
			       struct dasd_device  *device)
{
	struct dasd_eckd_private *private;
	int rc;

	private = (struct dasd_eckd_private *) device->private;
	if (!private->rdc_data.facilities.XRC_supported)
		return 0;

	/* switch on System Time Stamp - needed for XRC Support */
	pfxdata->define_extent.ga_extended |= 0x08; /* 'Time Stamp Valid'   */
	pfxdata->define_extent.ga_extended |= 0x02; /* 'Extended Parameter' */
	pfxdata->validity.time_stamp = 1;	    /* 'Time Stamp Valid'   */

	rc = get_sync_clock(&pfxdata->define_extent.ep_sys_time);
	/* Ignore return code if sync clock is switched off. */
	if (rc == -ENOSYS || rc == -EACCES)
		rc = 0;
	return rc;
}

static void fill_LRE_data(struct LRE_eckd_data *data, unsigned int trk,
			  unsigned int rec_on_trk, int count, int cmd,
			  struct dasd_device *device, unsigned int reclen,
			  unsigned int tlf)
{
	struct dasd_eckd_private *private;
	int sector;
	int dn, d;

	private = (struct dasd_eckd_private *) device->private;

	memset(data, 0, sizeof(*data));
	sector = 0;
	if (rec_on_trk) {
		switch (private->rdc_data.dev_type) {
		case 0x3390:
			dn = ceil_quot(reclen + 6, 232);
			d = 9 + ceil_quot(reclen + 6 * (dn + 1), 34);
			sector = (49 + (rec_on_trk - 1) * (10 + d)) / 8;
			break;
		case 0x3380:
			d = 7 + ceil_quot(reclen + 12, 32);
			sector = (39 + (rec_on_trk - 1) * (8 + d)) / 7;
			break;
		}
	}
	data->sector = sector;
	/* note: meaning of count depends on the operation
	 *	 for record based I/O it's the number of records, but for
	 *	 track based I/O it's the number of tracks
	 */
	data->count = count;
	switch (cmd) {
	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
		data->operation.orientation = 0x1;
		data->operation.operation = 0x03;
		data->count++;
		break;
	case DASD_ECKD_CCW_READ_RECORD_ZERO:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		data->count++;
		break;
	case DASD_ECKD_CCW_WRITE:
	case DASD_ECKD_CCW_WRITE_MT:
	case DASD_ECKD_CCW_WRITE_KD:
	case DASD_ECKD_CCW_WRITE_KD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x01;
		break;
	case DASD_ECKD_CCW_WRITE_CKD:
	case DASD_ECKD_CCW_WRITE_CKD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_WRITE_FULL_TRACK:
		data->operation.orientation = 0x0;
		data->operation.operation = 0x3F;
		data->extended_operation = 0x11;
		data->length = 0;
		data->extended_parameter_length = 0x02;
		if (data->count > 8) {
			data->extended_parameter[0] = 0xFF;
			data->extended_parameter[1] = 0xFF;
			data->extended_parameter[1] <<= (16 - count);
		} else {
			data->extended_parameter[0] = 0xFF;
			data->extended_parameter[0] <<= (8 - count);
			data->extended_parameter[1] = 0x00;
		}
		data->sector = 0xFF;
		break;
	case DASD_ECKD_CCW_WRITE_TRACK_DATA:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;	/* not tlf, as one might think */
		data->operation.operation = 0x3F;
		data->extended_operation = 0x23;
		break;
	case DASD_ECKD_CCW_READ:
	case DASD_ECKD_CCW_READ_MT:
	case DASD_ECKD_CCW_READ_KD:
	case DASD_ECKD_CCW_READ_KD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_READ_CKD:
	case DASD_ECKD_CCW_READ_CKD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_READ_COUNT:
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_READ_TRACK:
		data->operation.orientation = 0x1;
		data->operation.operation = 0x0C;
		data->extended_parameter_length = 0;
		data->sector = 0xFF;
		break;
	case DASD_ECKD_CCW_READ_TRACK_DATA:
		data->auxiliary.length_valid = 0x1;
		data->length = tlf;
		data->operation.operation = 0x0C;
		break;
	case DASD_ECKD_CCW_ERASE:
		data->length = reclen;
		data->auxiliary.length_valid = 0x1;
		data->operation.operation = 0x0b;
		break;
	default:
		DBF_DEV_EVENT(DBF_ERR, device,
			    "fill LRE unknown opcode 0x%x", cmd);
		BUG();
	}
	set_ch_t(&data->seek_addr,
		 trk / private->rdc_data.trk_per_cyl,
		 trk % private->rdc_data.trk_per_cyl);
	data->search_arg.cyl = data->seek_addr.cyl;
	data->search_arg.head = data->seek_addr.head;
	data->search_arg.record = rec_on_trk;
}

static int prefix_LRE(struct ccw1 *ccw, struct PFX_eckd_data *pfxdata,
		      unsigned int trk, unsigned int totrk, int cmd,
		      struct dasd_device *basedev, struct dasd_device *startdev,
		      unsigned char format, unsigned int rec_on_trk, int count,
		      unsigned int blksize, unsigned int tlf)
{
	struct dasd_eckd_private *basepriv, *startpriv;
	struct DE_eckd_data *dedata;
	struct LRE_eckd_data *lredata;
	u32 begcyl, endcyl;
	u16 heads, beghead, endhead;
	int rc = 0;

	basepriv = (struct dasd_eckd_private *) basedev->private;
	startpriv = (struct dasd_eckd_private *) startdev->private;
	dedata = &pfxdata->define_extent;
	lredata = &pfxdata->locate_record;

	ccw->cmd_code = DASD_ECKD_CCW_PFX;
	ccw->flags = 0;
	if (cmd == DASD_ECKD_CCW_WRITE_FULL_TRACK) {
		ccw->count = sizeof(*pfxdata) + 2;
		ccw->cda = (__u32) __pa(pfxdata);
		memset(pfxdata, 0, sizeof(*pfxdata) + 2);
	} else {
		ccw->count = sizeof(*pfxdata);
		ccw->cda = (__u32) __pa(pfxdata);
		memset(pfxdata, 0, sizeof(*pfxdata));
	}

	/* prefix data */
	if (format > 1) {
		DBF_DEV_EVENT(DBF_ERR, basedev,
			      "PFX LRE unknown format 0x%x", format);
		BUG();
		return -EINVAL;
	}
	pfxdata->format = format;
	pfxdata->base_address = basepriv->ned->unit_addr;
	pfxdata->base_lss = basepriv->ned->ID;
	pfxdata->validity.define_extent = 1;

	/* private uid is kept up to date, conf_data may be outdated */
	if (startpriv->uid.type != UA_BASE_DEVICE) {
		pfxdata->validity.verify_base = 1;
		if (startpriv->uid.type == UA_HYPER_PAV_ALIAS)
			pfxdata->validity.hyper_pav = 1;
	}

	/* define extend data (mostly)*/
	switch (cmd) {
	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
	case DASD_ECKD_CCW_READ_RECORD_ZERO:
	case DASD_ECKD_CCW_READ:
	case DASD_ECKD_CCW_READ_MT:
	case DASD_ECKD_CCW_READ_CKD:
	case DASD_ECKD_CCW_READ_CKD_MT:
	case DASD_ECKD_CCW_READ_KD:
	case DASD_ECKD_CCW_READ_KD_MT:
	case DASD_ECKD_CCW_READ_COUNT:
		dedata->mask.perm = 0x1;
		dedata->attributes.operation = basepriv->attrib.operation;
		break;
	case DASD_ECKD_CCW_READ_TRACK:
	case DASD_ECKD_CCW_READ_TRACK_DATA:
		dedata->mask.perm = 0x1;
		dedata->attributes.operation = basepriv->attrib.operation;
		dedata->blk_size = 0;
		break;
	case DASD_ECKD_CCW_WRITE:
	case DASD_ECKD_CCW_WRITE_MT:
	case DASD_ECKD_CCW_WRITE_KD:
	case DASD_ECKD_CCW_WRITE_KD_MT:
		dedata->mask.perm = 0x02;
		dedata->attributes.operation = basepriv->attrib.operation;
		rc = check_XRC_on_prefix(pfxdata, basedev);
		break;
	case DASD_ECKD_CCW_WRITE_CKD:
	case DASD_ECKD_CCW_WRITE_CKD_MT:
		dedata->attributes.operation = DASD_BYPASS_CACHE;
		rc = check_XRC_on_prefix(pfxdata, basedev);
		break;
	case DASD_ECKD_CCW_ERASE:
	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
		dedata->mask.perm = 0x3;
		dedata->mask.auth = 0x1;
		dedata->attributes.operation = DASD_BYPASS_CACHE;
		rc = check_XRC_on_prefix(pfxdata, basedev);
		break;
	case DASD_ECKD_CCW_WRITE_FULL_TRACK:
		dedata->mask.perm = 0x03;
		dedata->attributes.operation = basepriv->attrib.operation;
		dedata->blk_size = 0;
		break;
	case DASD_ECKD_CCW_WRITE_TRACK_DATA:
		dedata->mask.perm = 0x02;
		dedata->attributes.operation = basepriv->attrib.operation;
		dedata->blk_size = blksize;
		rc = check_XRC_on_prefix(pfxdata, basedev);
		break;
	default:
		DBF_DEV_EVENT(DBF_ERR, basedev,
			    "PFX LRE unknown opcode 0x%x", cmd);
		BUG();
		return -EINVAL;
	}

	dedata->attributes.mode = 0x3;	/* ECKD */

	if ((basepriv->rdc_data.cu_type == 0x2105 ||
	     basepriv->rdc_data.cu_type == 0x2107 ||
	     basepriv->rdc_data.cu_type == 0x1750)
	    && !(basepriv->uses_cdl && trk < 2))
		dedata->ga_extended |= 0x40; /* Regular Data Format Mode */

	heads = basepriv->rdc_data.trk_per_cyl;
	begcyl = trk / heads;
	beghead = trk % heads;
	endcyl = totrk / heads;
	endhead = totrk % heads;

	/* check for sequential prestage - enhance cylinder range */
	if (dedata->attributes.operation == DASD_SEQ_PRESTAGE ||
	    dedata->attributes.operation == DASD_SEQ_ACCESS) {

		if (endcyl + basepriv->attrib.nr_cyl < basepriv->real_cyl)
			endcyl += basepriv->attrib.nr_cyl;
		else
			endcyl = (basepriv->real_cyl - 1);
	}

	set_ch_t(&dedata->beg_ext, begcyl, beghead);
	set_ch_t(&dedata->end_ext, endcyl, endhead);

	if (format == 1) {
		fill_LRE_data(lredata, trk, rec_on_trk, count, cmd,
			      basedev, blksize, tlf);
	}

	return rc;
}

static int prefix(struct ccw1 *ccw, struct PFX_eckd_data *pfxdata,
		  unsigned int trk, unsigned int totrk, int cmd,
		  struct dasd_device *basedev, struct dasd_device *startdev)
{
	return prefix_LRE(ccw, pfxdata, trk, totrk, cmd, basedev, startdev,
			  0, 0, 0, 0, 0);
}

static void
locate_record(struct ccw1 *ccw, struct LO_eckd_data *data, unsigned int trk,
	      unsigned int rec_on_trk, int no_rec, int cmd,
	      struct dasd_device * device, int reclen)
{
	struct dasd_eckd_private *private;
	int sector;
	int dn, d;

	private = (struct dasd_eckd_private *) device->private;

	DBF_DEV_EVENT(DBF_INFO, device,
		  "Locate: trk %d, rec %d, no_rec %d, cmd %d, reclen %d",
		  trk, rec_on_trk, no_rec, cmd, reclen);

	ccw->cmd_code = DASD_ECKD_CCW_LOCATE_RECORD;
	ccw->flags = 0;
	ccw->count = 16;
	ccw->cda = (__u32) __pa(data);

	memset(data, 0, sizeof(struct LO_eckd_data));
	sector = 0;
	if (rec_on_trk) {
		switch (private->rdc_data.dev_type) {
		case 0x3390:
			dn = ceil_quot(reclen + 6, 232);
			d = 9 + ceil_quot(reclen + 6 * (dn + 1), 34);
			sector = (49 + (rec_on_trk - 1) * (10 + d)) / 8;
			break;
		case 0x3380:
			d = 7 + ceil_quot(reclen + 12, 32);
			sector = (39 + (rec_on_trk - 1) * (8 + d)) / 7;
			break;
		}
	}
	data->sector = sector;
	data->count = no_rec;
	switch (cmd) {
	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
		data->operation.orientation = 0x1;
		data->operation.operation = 0x03;
		data->count++;
		break;
	case DASD_ECKD_CCW_READ_RECORD_ZERO:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		data->count++;
		break;
	case DASD_ECKD_CCW_WRITE:
	case DASD_ECKD_CCW_WRITE_MT:
	case DASD_ECKD_CCW_WRITE_KD:
	case DASD_ECKD_CCW_WRITE_KD_MT:
		data->auxiliary.last_bytes_used = 0x1;
		data->length = reclen;
		data->operation.operation = 0x01;
		break;
	case DASD_ECKD_CCW_WRITE_CKD:
	case DASD_ECKD_CCW_WRITE_CKD_MT:
		data->auxiliary.last_bytes_used = 0x1;
		data->length = reclen;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_READ:
	case DASD_ECKD_CCW_READ_MT:
	case DASD_ECKD_CCW_READ_KD:
	case DASD_ECKD_CCW_READ_KD_MT:
		data->auxiliary.last_bytes_used = 0x1;
		data->length = reclen;
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_READ_CKD:
	case DASD_ECKD_CCW_READ_CKD_MT:
		data->auxiliary.last_bytes_used = 0x1;
		data->length = reclen;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_READ_COUNT:
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_ERASE:
		data->length = reclen;
		data->auxiliary.last_bytes_used = 0x1;
		data->operation.operation = 0x0b;
		break;
	default:
		DBF_DEV_EVENT(DBF_ERR, device, "unknown locate record "
			      "opcode 0x%x", cmd);
	}
	set_ch_t(&data->seek_addr,
		 trk / private->rdc_data.trk_per_cyl,
		 trk % private->rdc_data.trk_per_cyl);
	data->search_arg.cyl = data->seek_addr.cyl;
	data->search_arg.head = data->seek_addr.head;
	data->search_arg.record = rec_on_trk;
}

/*
 * Returns 1 if the block is one of the special blocks that needs
 * to get read/written with the KD variant of the command.
 * That is DASD_ECKD_READ_KD_MT instead of DASD_ECKD_READ_MT and
 * DASD_ECKD_WRITE_KD_MT instead of DASD_ECKD_WRITE_MT.
 * Luckily the KD variants differ only by one bit (0x08) from the
 * normal variant. So don't wonder about code like:
 * if (dasd_eckd_cdl_special(blk_per_trk, recid))
 *         ccw->cmd_code |= 0x8;
 */
static inline int
dasd_eckd_cdl_special(int blk_per_trk, int recid)
{
	if (recid < 3)
		return 1;
	if (recid < blk_per_trk)
		return 0;
	if (recid < 2 * blk_per_trk)
		return 1;
	return 0;
}

/*
 * Returns the record size for the special blocks of the cdl format.
 * Only returns something useful if dasd_eckd_cdl_special is true
 * for the recid.
 */
static inline int
dasd_eckd_cdl_reclen(int recid)
{
	if (recid < 3)
		return sizes_trk0[recid];
	return LABEL_SIZE;
}
/* create unique id from private structure. */
static void create_uid(struct dasd_eckd_private *private)
{
	int count;
	struct dasd_uid *uid;

	uid = &private->uid;
	memset(uid, 0, sizeof(struct dasd_uid));
	memcpy(uid->vendor, private->ned->HDA_manufacturer,
	       sizeof(uid->vendor) - 1);
	EBCASC(uid->vendor, sizeof(uid->vendor) - 1);
	memcpy(uid->serial, private->ned->HDA_location,
	       sizeof(uid->serial) - 1);
	EBCASC(uid->serial, sizeof(uid->serial) - 1);
	uid->ssid = private->gneq->subsystemID;
	uid->real_unit_addr = private->ned->unit_addr;
	if (private->sneq) {
		uid->type = private->sneq->sua_flags;
		if (uid->type == UA_BASE_PAV_ALIAS)
			uid->base_unit_addr = private->sneq->base_unit_addr;
	} else {
		uid->type = UA_BASE_DEVICE;
	}
	if (private->vdsneq) {
		for (count = 0; count < 16; count++) {
			sprintf(uid->vduit+2*count, "%02x",
				private->vdsneq->uit[count]);
		}
	}
}

/*
 * Generate device unique id that specifies the physical device.
 */
static int dasd_eckd_generate_uid(struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	unsigned long flags;

	private = (struct dasd_eckd_private *) device->private;
	if (!private)
		return -ENODEV;
	if (!private->ned || !private->gneq)
		return -ENODEV;
	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
	create_uid(private);
	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
	return 0;
}

static int dasd_eckd_get_uid(struct dasd_device *device, struct dasd_uid *uid)
{
	struct dasd_eckd_private *private;
	unsigned long flags;

	if (device->private) {
		private = (struct dasd_eckd_private *)device->private;
		spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
		*uid = private->uid;
		spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
		return 0;
	}
	return -EINVAL;
}

/*
 * compare device UID with data of a given dasd_eckd_private structure
 * return 0 for match
 */
static int dasd_eckd_compare_path_uid(struct dasd_device *device,
				      struct dasd_eckd_private *private)
{
	struct dasd_uid device_uid;

	create_uid(private);
	dasd_eckd_get_uid(device, &device_uid);

	return memcmp(&device_uid, &private->uid, sizeof(struct dasd_uid));
}

static void dasd_eckd_fill_rcd_cqr(struct dasd_device *device,
				   struct dasd_ccw_req *cqr,
				   __u8 *rcd_buffer,
				   __u8 lpm)
{
	struct ccw1 *ccw;
	/*
	 * buffer has to start with EBCDIC "V1.0" to show
	 * support for virtual device SNEQ
	 */
	rcd_buffer[0] = 0xE5;
	rcd_buffer[1] = 0xF1;
	rcd_buffer[2] = 0x4B;
	rcd_buffer[3] = 0xF0;

	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_RCD;
	ccw->flags = 0;
	ccw->cda = (__u32)(addr_t)rcd_buffer;
	ccw->count = DASD_ECKD_RCD_DATA_SIZE;
	cqr->magic = DASD_ECKD_MAGIC;

	cqr->startdev = device;
	cqr->memdev = device;
	cqr->block = NULL;
	cqr->expires = 10*HZ;
	cqr->lpm = lpm;
	cqr->retries = 256;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	set_bit(DASD_CQR_VERIFY_PATH, &cqr->flags);
}

/*
 * Wakeup helper for read_conf
 * if the cqr is not done and needs some error recovery
 * the buffer has to be re-initialized with the EBCDIC "V1.0"
 * to show support for virtual device SNEQ
 */
static void read_conf_cb(struct dasd_ccw_req *cqr, void *data)
{
	struct ccw1 *ccw;
	__u8 *rcd_buffer;

	if (cqr->status !=  DASD_CQR_DONE) {
		ccw = cqr->cpaddr;
		rcd_buffer = (__u8 *)((addr_t) ccw->cda);
		memset(rcd_buffer, 0, sizeof(*rcd_buffer));

		rcd_buffer[0] = 0xE5;
		rcd_buffer[1] = 0xF1;
		rcd_buffer[2] = 0x4B;
		rcd_buffer[3] = 0xF0;
	}
	dasd_wakeup_cb(cqr, data);
}

static int dasd_eckd_read_conf_immediately(struct dasd_device *device,
					   struct dasd_ccw_req *cqr,
					   __u8 *rcd_buffer,
					   __u8 lpm)
{
	struct ciw *ciw;
	int rc;
	/*
	 * sanity check: scan for RCD command in extended SenseID data
	 * some devices do not support RCD
	 */
	ciw = ccw_device_get_ciw(device->cdev, CIW_TYPE_RCD);
	if (!ciw || ciw->cmd != DASD_ECKD_CCW_RCD)
		return -EOPNOTSUPP;

	dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buffer, lpm);
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags);
	cqr->retries = 5;
	cqr->callback = read_conf_cb;
	rc = dasd_sleep_on_immediatly(cqr);
	return rc;
}

static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
				   void **rcd_buffer,
				   int *rcd_buffer_size, __u8 lpm)
{
	struct ciw *ciw;
	char *rcd_buf = NULL;
	int ret;
	struct dasd_ccw_req *cqr;

	/*
	 * sanity check: scan for RCD command in extended SenseID data
	 * some devices do not support RCD
	 */
	ciw = ccw_device_get_ciw(device->cdev, CIW_TYPE_RCD);
	if (!ciw || ciw->cmd != DASD_ECKD_CCW_RCD) {
		ret = -EOPNOTSUPP;
		goto out_error;
	}
	rcd_buf = kzalloc(DASD_ECKD_RCD_DATA_SIZE, GFP_KERNEL | GFP_DMA);
	if (!rcd_buf) {
		ret = -ENOMEM;
		goto out_error;
	}
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* RCD */,
				   0, /* use rcd_buf as data ara */
				   device);
	if (IS_ERR(cqr)) {
		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
			      "Could not allocate RCD request");
		ret = -ENOMEM;
		goto out_error;
	}
	dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buf, lpm);
	cqr->callback = read_conf_cb;
	ret = dasd_sleep_on(cqr);
	/*
	 * on success we update the user input parms
	 */
	dasd_sfree_request(cqr, cqr->memdev);
	if (ret)
		goto out_error;

	*rcd_buffer_size = DASD_ECKD_RCD_DATA_SIZE;
	*rcd_buffer = rcd_buf;
	return 0;
out_error:
	kfree(rcd_buf);
	*rcd_buffer = NULL;
	*rcd_buffer_size = 0;
	return ret;
}

static int dasd_eckd_identify_conf_parts(struct dasd_eckd_private *private)
{

	struct dasd_sneq *sneq;
	int i, count;

	private->ned = NULL;
	private->sneq = NULL;
	private->vdsneq = NULL;
	private->gneq = NULL;
	count = private->conf_len / sizeof(struct dasd_sneq);
	sneq = (struct dasd_sneq *)private->conf_data;
	for (i = 0; i < count; ++i) {
		if (sneq->flags.identifier == 1 && sneq->format == 1)
			private->sneq = sneq;
		else if (sneq->flags.identifier == 1 && sneq->format == 4)
			private->vdsneq = (struct vd_sneq *)sneq;
		else if (sneq->flags.identifier == 2)
			private->gneq = (struct dasd_gneq *)sneq;
		else if (sneq->flags.identifier == 3 && sneq->res1 == 1)
			private->ned = (struct dasd_ned *)sneq;
		sneq++;
	}
	if (!private->ned || !private->gneq) {
		private->ned = NULL;
		private->sneq = NULL;
		private->vdsneq = NULL;
		private->gneq = NULL;
		return -EINVAL;
	}
	return 0;

};

static unsigned char dasd_eckd_path_access(void *conf_data, int conf_len)
{
	struct dasd_gneq *gneq;
	int i, count, found;

	count = conf_len / sizeof(*gneq);
	gneq = (struct dasd_gneq *)conf_data;
	found = 0;
	for (i = 0; i < count; ++i) {
		if (gneq->flags.identifier == 2) {
			found = 1;
			break;
		}
		gneq++;
	}
	if (found)
		return ((char *)gneq)[18] & 0x07;
	else
		return 0;
}

static int dasd_eckd_read_conf(struct dasd_device *device)
{
	void *conf_data;
	int conf_len, conf_data_saved;
	int rc;
	__u8 lpm, opm;
	struct dasd_eckd_private *private, path_private;
	struct dasd_path *path_data;
	struct dasd_uid *uid;
	char print_path_uid[60], print_device_uid[60];

	private = (struct dasd_eckd_private *) device->private;
	path_data = &device->path_data;
	opm = ccw_device_get_path_mask(device->cdev);
	conf_data_saved = 0;
	/* get configuration data per operational path */
	for (lpm = 0x80; lpm; lpm>>= 1) {
		if (!(lpm & opm))
			continue;
		rc = dasd_eckd_read_conf_lpm(device, &conf_data,
					     &conf_len, lpm);
		if (rc && rc != -EOPNOTSUPP) {	/* -EOPNOTSUPP is ok */
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
					"Read configuration data returned "
					"error %d", rc);
			return rc;
		}
		if (conf_data == NULL) {
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
					"No configuration data "
					"retrieved");
			/* no further analysis possible */
			path_data->opm |= lpm;
			continue;	/* no error */
		}
		/* save first valid configuration data */
		if (!conf_data_saved) {
			kfree(private->conf_data);
			private->conf_data = conf_data;
			private->conf_len = conf_len;
			if (dasd_eckd_identify_conf_parts(private)) {
				private->conf_data = NULL;
				private->conf_len = 0;
				kfree(conf_data);
				continue;
			}
			/*
			 * build device UID that other path data
			 * can be compared to it
			 */
			dasd_eckd_generate_uid(device);
			conf_data_saved++;
		} else {
			path_private.conf_data = conf_data;
			path_private.conf_len = DASD_ECKD_RCD_DATA_SIZE;
			if (dasd_eckd_identify_conf_parts(
				    &path_private)) {
				path_private.conf_data = NULL;
				path_private.conf_len = 0;
				kfree(conf_data);
				continue;
			}

			if (dasd_eckd_compare_path_uid(
				    device, &path_private)) {
				uid = &path_private.uid;
				if (strlen(uid->vduit) > 0)
					snprintf(print_path_uid,
						 sizeof(print_path_uid),
						 "%s.%s.%04x.%02x.%s",
						 uid->vendor, uid->serial,
						 uid->ssid, uid->real_unit_addr,
						 uid->vduit);
				else
					snprintf(print_path_uid,
						 sizeof(print_path_uid),
						 "%s.%s.%04x.%02x",
						 uid->vendor, uid->serial,
						 uid->ssid,
						 uid->real_unit_addr);
				uid = &private->uid;
				if (strlen(uid->vduit) > 0)
					snprintf(print_device_uid,
						 sizeof(print_device_uid),
						 "%s.%s.%04x.%02x.%s",
						 uid->vendor, uid->serial,
						 uid->ssid, uid->real_unit_addr,
						 uid->vduit);
				else
					snprintf(print_device_uid,
						 sizeof(print_device_uid),
						 "%s.%s.%04x.%02x",
						 uid->vendor, uid->serial,
						 uid->ssid,
						 uid->real_unit_addr);
				dev_err(&device->cdev->dev,
					"Not all channel paths lead to "
					"the same device, path %02X leads to "
					"device %s instead of %s\n", lpm,
					print_path_uid, print_device_uid);
				return -EINVAL;
			}

			path_private.conf_data = NULL;
			path_private.conf_len = 0;
		}
		switch (dasd_eckd_path_access(conf_data, conf_len)) {
		case 0x02:
			path_data->npm |= lpm;
			break;
		case 0x03:
			path_data->ppm |= lpm;
			break;
		}
		path_data->opm |= lpm;

		if (conf_data != private->conf_data)
			kfree(conf_data);
	}

	return 0;
}

static int verify_fcx_max_data(struct dasd_device *device, __u8 lpm)
{
	struct dasd_eckd_private *private;
	int mdc;
	u32 fcx_max_data;

	private = (struct dasd_eckd_private *) device->private;
	if (private->fcx_max_data) {
		mdc = ccw_device_get_mdc(device->cdev, lpm);
		if ((mdc < 0)) {
			dev_warn(&device->cdev->dev,
				 "Detecting the maximum data size for zHPF "
				 "requests failed (rc=%d) for a new path %x\n",
				 mdc, lpm);
			return mdc;
		}
		fcx_max_data = mdc * FCX_MAX_DATA_FACTOR;
		if (fcx_max_data < private->fcx_max_data) {
			dev_warn(&device->cdev->dev,
				 "The maximum data size for zHPF requests %u "
				 "on a new path %x is below the active maximum "
				 "%u\n", fcx_max_data, lpm,
				 private->fcx_max_data);
			return -EACCES;
		}
	}
	return 0;
}

static int rebuild_device_uid(struct dasd_device *device,
			      struct path_verification_work_data *data)
{
	struct dasd_eckd_private *private;
	struct dasd_path *path_data;
	__u8 lpm, opm;
	int rc;

	rc = -ENODEV;
	private = (struct dasd_eckd_private *) device->private;
	path_data = &device->path_data;
	opm = device->path_data.opm;

	for (lpm = 0x80; lpm; lpm >>= 1) {
		if (!(lpm & opm))
			continue;
		memset(&data->rcd_buffer, 0, sizeof(data->rcd_buffer));
		memset(&data->cqr, 0, sizeof(data->cqr));
		data->cqr.cpaddr = &data->ccw;
		rc = dasd_eckd_read_conf_immediately(device, &data->cqr,
						     data->rcd_buffer,
						     lpm);

		if (rc) {
			if (rc == -EOPNOTSUPP) /* -EOPNOTSUPP is ok */
				continue;
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
					"Read configuration data "
					"returned error %d", rc);
			break;
		}
		memcpy(private->conf_data, data->rcd_buffer,
		       DASD_ECKD_RCD_DATA_SIZE);
		if (dasd_eckd_identify_conf_parts(private)) {
			rc = -ENODEV;
		} else /* first valid path is enough */
			break;
	}

	if (!rc)
		rc = dasd_eckd_generate_uid(device);

	return rc;
}

static void do_path_verification_work(struct work_struct *work)
{
	struct path_verification_work_data *data;
	struct dasd_device *device;
	struct dasd_eckd_private path_private;
	struct dasd_uid *uid;
	__u8 path_rcd_buf[DASD_ECKD_RCD_DATA_SIZE];
	__u8 lpm, opm, npm, ppm, epm;
	unsigned long flags;
	char print_uid[60];
	int rc;

	data = container_of(work, struct path_verification_work_data, worker);
	device = data->device;

	/* delay path verification until device was resumed */
	if (test_bit(DASD_FLAG_SUSPENDED, &device->flags)) {
		schedule_work(work);
		return;
	}

	opm = 0;
	npm = 0;
	ppm = 0;
	epm = 0;
	for (lpm = 0x80; lpm; lpm >>= 1) {
		if (!(lpm & data->tbvpm))
			continue;
		memset(&data->rcd_buffer, 0, sizeof(data->rcd_buffer));
		memset(&data->cqr, 0, sizeof(data->cqr));
		data->cqr.cpaddr = &data->ccw;
		rc = dasd_eckd_read_conf_immediately(device, &data->cqr,
						     data->rcd_buffer,
						     lpm);
		if (!rc) {
			switch (dasd_eckd_path_access(data->rcd_buffer,
						      DASD_ECKD_RCD_DATA_SIZE)
				) {
			case 0x02:
				npm |= lpm;
				break;
			case 0x03:
				ppm |= lpm;
				break;
			}
			opm |= lpm;
		} else if (rc == -EOPNOTSUPP) {
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
					"path verification: No configuration "
					"data retrieved");
			opm |= lpm;
		} else if (rc == -EAGAIN) {
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
					"path verification: device is stopped,"
					" try again later");
			epm |= lpm;
		} else {
			dev_warn(&device->cdev->dev,
				 "Reading device feature codes failed "
				 "(rc=%d) for new path %x\n", rc, lpm);
			continue;
		}
		if (verify_fcx_max_data(device, lpm)) {
			opm &= ~lpm;
			npm &= ~lpm;
			ppm &= ~lpm;
			continue;
		}

		/*
		 * save conf_data for comparison after
		 * rebuild_device_uid may have changed
		 * the original data
		 */
		memcpy(&path_rcd_buf, data->rcd_buffer,
		       DASD_ECKD_RCD_DATA_SIZE);
		path_private.conf_data = (void *) &path_rcd_buf;
		path_private.conf_len = DASD_ECKD_RCD_DATA_SIZE;
		if (dasd_eckd_identify_conf_parts(&path_private)) {
			path_private.conf_data = NULL;
			path_private.conf_len = 0;
			continue;
		}

		/*
		 * compare path UID with device UID only if at least
		 * one valid path is left
		 * in other case the device UID may have changed and
		 * the first working path UID will be used as device UID
		 */
		if (device->path_data.opm &&
		    dasd_eckd_compare_path_uid(device, &path_private)) {
			/*
			 * the comparison was not successful
			 * rebuild the device UID with at least one
			 * known path in case a z/VM hyperswap command
			 * has changed the device
			 *
			 * after this compare again
			 *
			 * if either the rebuild or the recompare fails
			 * the path can not be used
			 */
			if (rebuild_device_uid(device, data) ||
			    dasd_eckd_compare_path_uid(
				    device, &path_private)) {
				uid = &path_private.uid;
				if (strlen(uid->vduit) > 0)
					snprintf(print_uid, sizeof(print_uid),
						 "%s.%s.%04x.%02x.%s",
						 uid->vendor, uid->serial,
						 uid->ssid, uid->real_unit_addr,
						 uid->vduit);
				else
					snprintf(print_uid, sizeof(print_uid),
						 "%s.%s.%04x.%02x",
						 uid->vendor, uid->serial,
						 uid->ssid,
						 uid->real_unit_addr);
				dev_err(&device->cdev->dev,
					"The newly added channel path %02X "
					"will not be used because it leads "
					"to a different device %s\n",
					lpm, print_uid);
				opm &= ~lpm;
				npm &= ~lpm;
				ppm &= ~lpm;
				continue;
			}
		}

		/*
		 * There is a small chance that a path is lost again between
		 * above path verification and the following modification of
		 * the device opm mask. We could avoid that race here by using
		 * yet another path mask, but we rather deal with this unlikely
		 * situation in dasd_start_IO.
		 */
		spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
		if (!device->path_data.opm && opm) {
			device->path_data.opm = opm;
			dasd_generic_path_operational(device);
		} else
			device->path_data.opm |= opm;
		device->path_data.npm |= npm;
		device->path_data.ppm |= ppm;
		device->path_data.tbvpm |= epm;
		spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
	}

	dasd_put_device(device);
	if (data->isglobal)
		mutex_unlock(&dasd_path_verification_mutex);
	else
		kfree(data);
}

static int dasd_eckd_verify_path(struct dasd_device *device, __u8 lpm)
{
	struct path_verification_work_data *data;

	data = kmalloc(sizeof(*data), GFP_ATOMIC | GFP_DMA);
	if (!data) {
		if (mutex_trylock(&dasd_path_verification_mutex)) {
			data = path_verification_worker;
			data->isglobal = 1;
		} else
			return -ENOMEM;
	} else {
		memset(data, 0, sizeof(*data));
		data->isglobal = 0;
	}
	INIT_WORK(&data->worker, do_path_verification_work);
	dasd_get_device(device);
	data->device = device;
	data->tbvpm = lpm;
	schedule_work(&data->worker);
	return 0;
}

static int dasd_eckd_read_features(struct dasd_device *device)
{
	struct dasd_psf_prssd_data *prssdp;
	struct dasd_rssd_features *features;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	int rc;
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) device->private;
	memset(&private->features, 0, sizeof(struct dasd_rssd_features));
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */	+ 1 /* RSSD */,
				   (sizeof(struct dasd_psf_prssd_data) +
				    sizeof(struct dasd_rssd_features)),
				   device);
	if (IS_ERR(cqr)) {
		DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s", "Could not "
				"allocate initialization request");
		return PTR_ERR(cqr);
	}
	cqr->startdev = device;
	cqr->memdev = device;
	cqr->block = NULL;
	cqr->retries = 256;
	cqr->expires = 10 * HZ;

	/* Prepare for Read Subsystem Data */
	prssdp = (struct dasd_psf_prssd_data *) cqr->data;
	memset(prssdp, 0, sizeof(struct dasd_psf_prssd_data));
	prssdp->order = PSF_ORDER_PRSSD;
	prssdp->suborder = 0x41;	/* Read Feature Codes */
	/* all other bytes of prssdp must be zero */

	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_PSF;
	ccw->count = sizeof(struct dasd_psf_prssd_data);
	ccw->flags |= CCW_FLAG_CC;
	ccw->cda = (__u32)(addr_t) prssdp;

	/* Read Subsystem Data - feature codes */
	features = (struct dasd_rssd_features *) (prssdp + 1);
	memset(features, 0, sizeof(struct dasd_rssd_features));

	ccw++;
	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
	ccw->count = sizeof(struct dasd_rssd_features);
	ccw->cda = (__u32)(addr_t) features;

	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	rc = dasd_sleep_on(cqr);
	if (rc == 0) {
		prssdp = (struct dasd_psf_prssd_data *) cqr->data;
		features = (struct dasd_rssd_features *) (prssdp + 1);
		memcpy(&private->features, features,
		       sizeof(struct dasd_rssd_features));
	} else
		dev_warn(&device->cdev->dev, "Reading device feature codes"
			 " failed with rc=%d\n", rc);
	dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}


/*
 * Build CP for Perform Subsystem Function - SSC.
 */
static struct dasd_ccw_req *dasd_eckd_build_psf_ssc(struct dasd_device *device,
						    int enable_pav)
{
	struct dasd_ccw_req *cqr;
	struct dasd_psf_ssc_data *psf_ssc_data;
	struct ccw1 *ccw;

	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */ ,
				  sizeof(struct dasd_psf_ssc_data),
				  device);

	if (IS_ERR(cqr)) {
		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
			   "Could not allocate PSF-SSC request");
		return cqr;
	}
	psf_ssc_data = (struct dasd_psf_ssc_data *)cqr->data;
	psf_ssc_data->order = PSF_ORDER_SSC;
	psf_ssc_data->suborder = 0xc0;
	if (enable_pav) {
		psf_ssc_data->suborder |= 0x08;
		psf_ssc_data->reserved[0] = 0x88;
	}
	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_PSF;
	ccw->cda = (__u32)(addr_t)psf_ssc_data;
	ccw->count = 66;

	cqr->startdev = device;
	cqr->memdev = device;
	cqr->block = NULL;
	cqr->retries = 256;
	cqr->expires = 10*HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	return cqr;
}

/*
 * Perform Subsystem Function.
 * It is necessary to trigger CIO for channel revalidation since this
 * call might change behaviour of DASD devices.
 */
static int
dasd_eckd_psf_ssc(struct dasd_device *device, int enable_pav,
		  unsigned long flags)
{
	struct dasd_ccw_req *cqr;
	int rc;

	cqr = dasd_eckd_build_psf_ssc(device, enable_pav);
	if (IS_ERR(cqr))
		return PTR_ERR(cqr);

	/*
	 * set flags e.g. turn on failfast, to prevent blocking
	 * the calling function should handle failed requests
	 */
	cqr->flags |= flags;

	rc = dasd_sleep_on(cqr);
	if (!rc)
		/* trigger CIO to reprobe devices */
		css_schedule_reprobe();
	else if (cqr->intrc == -EAGAIN)
		rc = -EAGAIN;

	dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * Valide storage server of current device.
 */
static int dasd_eckd_validate_server(struct dasd_device *device,
				     unsigned long flags)
{
	int rc;
	struct dasd_eckd_private *private;
	int enable_pav;

	private = (struct dasd_eckd_private *) device->private;
	if (private->uid.type == UA_BASE_PAV_ALIAS ||
	    private->uid.type == UA_HYPER_PAV_ALIAS)
		return 0;
	if (dasd_nopav || MACHINE_IS_VM)
		enable_pav = 0;
	else
		enable_pav = 1;
	rc = dasd_eckd_psf_ssc(device, enable_pav, flags);

	/* may be requested feature is not available on server,
	 * therefore just report error and go ahead */
	DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "PSF-SSC for SSID %04x "
			"returned rc=%d", private->uid.ssid, rc);
	return rc;
}

/*
 * worker to do a validate server in case of a lost pathgroup
 */
static void dasd_eckd_do_validate_server(struct work_struct *work)
{
	struct dasd_device *device = container_of(work, struct dasd_device,
						  kick_validate);
	if (dasd_eckd_validate_server(device, DASD_CQR_FLAGS_FAILFAST)
	    == -EAGAIN) {
		/* schedule worker again if failed */
		schedule_work(&device->kick_validate);
		return;
	}

	dasd_put_device(device);
}

static void dasd_eckd_kick_validate_server(struct dasd_device *device)
{
	dasd_get_device(device);
	/* exit if device not online or in offline processing */
	if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
	   device->state < DASD_STATE_ONLINE) {
		dasd_put_device(device);
		return;
	}
	/* queue call to do_validate_server to the kernel event daemon. */
	schedule_work(&device->kick_validate);
}

static u32 get_fcx_max_data(struct dasd_device *device)
{
#if defined(CONFIG_64BIT)
	int tpm, mdc;
	int fcx_in_css, fcx_in_gneq, fcx_in_features;
	struct dasd_eckd_private *private;

	if (dasd_nofcx)
		return 0;
	/* is transport mode supported? */
	private = (struct dasd_eckd_private *) device->private;
	fcx_in_css = css_general_characteristics.fcx;
	fcx_in_gneq = private->gneq->reserved2[7] & 0x04;
	fcx_in_features = private->features.feature[40] & 0x80;
	tpm = fcx_in_css && fcx_in_gneq && fcx_in_features;

	if (!tpm)
		return 0;

	mdc = ccw_device_get_mdc(device->cdev, 0);
	if (mdc < 0) {
		dev_warn(&device->cdev->dev, "Detecting the maximum supported"
			 " data size for zHPF requests failed\n");
		return 0;
	} else
		return mdc * FCX_MAX_DATA_FACTOR;
#else
	return 0;
#endif
}

/*
 * Check device characteristics.
 * If the device is accessible using ECKD discipline, the device is enabled.
 */
static int
dasd_eckd_check_characteristics(struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	struct dasd_block *block;
	struct dasd_uid temp_uid;
	int rc, i;
	int readonly;
	unsigned long value;

	/* setup work queue for validate server*/
	INIT_WORK(&device->kick_validate, dasd_eckd_do_validate_server);

	if (!ccw_device_is_pathgroup(device->cdev)) {
		dev_warn(&device->cdev->dev,
			 "A channel path group could not be established\n");
		return -EIO;
	}
	if (!ccw_device_is_multipath(device->cdev)) {
		dev_info(&device->cdev->dev,
			 "The DASD is not operating in multipath mode\n");
	}
	private = (struct dasd_eckd_private *) device->private;
	if (!private) {
		private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
		if (!private) {
			dev_warn(&device->cdev->dev,
				 "Allocating memory for private DASD data "
				 "failed\n");
			return -ENOMEM;
		}
		device->private = (void *) private;
	} else {
		memset(private, 0, sizeof(*private));
	}
	/* Invalidate status of initial analysis. */
	private->init_cqr_status = -1;
	/* Set default cache operations. */
	private->attrib.operation = DASD_NORMAL_CACHE;
	private->attrib.nr_cyl = 0;

	/* Read Configuration Data */
	rc = dasd_eckd_read_conf(device);
	if (rc)
		goto out_err1;

	/* set default timeout */
	device->default_expires = DASD_EXPIRES;
	if (private->gneq) {
		value = 1;
		for (i = 0; i < private->gneq->timeout.value; i++)
			value = 10 * value;
		value = value * private->gneq->timeout.number;
		/* do not accept useless values */
		if (value != 0 && value <= DASD_EXPIRES_MAX)
			device->default_expires = value;
	}

	dasd_eckd_get_uid(device, &temp_uid);
	if (temp_uid.type == UA_BASE_DEVICE) {
		block = dasd_alloc_block();
		if (IS_ERR(block)) {
			DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
					"could not allocate dasd "
					"block structure");
			rc = PTR_ERR(block);
			goto out_err1;
		}
		device->block = block;
		block->base = device;
	}

	/* register lcu with alias handling, enable PAV */
	rc = dasd_alias_make_device_known_to_lcu(device);
	if (rc)
		goto out_err2;

	dasd_eckd_validate_server(device, 0);

	/* device may report different configuration data after LCU setup */
	rc = dasd_eckd_read_conf(device);
	if (rc)
		goto out_err3;

	/* Read Feature Codes */
	dasd_eckd_read_features(device);

	/* Read Device Characteristics */
	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
					 &private->rdc_data, 64);
	if (rc) {
		DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
				"Read device characteristic failed, rc=%d", rc);
		goto out_err3;
	}

	if ((device->features & DASD_FEATURE_USERAW) &&
	    !(private->rdc_data.facilities.RT_in_LR)) {
		dev_err(&device->cdev->dev, "The storage server does not "
			"support raw-track access\n");
		rc = -EINVAL;
		goto out_err3;
	}

	/* find the valid cylinder size */
	if (private->rdc_data.no_cyl == LV_COMPAT_CYL &&
	    private->rdc_data.long_no_cyl)
		private->real_cyl = private->rdc_data.long_no_cyl;
	else
		private->real_cyl = private->rdc_data.no_cyl;

	private->fcx_max_data = get_fcx_max_data(device);

	readonly = dasd_device_is_ro(device);
	if (readonly)
		set_bit(DASD_FLAG_DEVICE_RO, &device->flags);

	dev_info(&device->cdev->dev, "New DASD %04X/%02X (CU %04X/%02X) "
		 "with %d cylinders, %d heads, %d sectors%s\n",
		 private->rdc_data.dev_type,
		 private->rdc_data.dev_model,
		 private->rdc_data.cu_type,
		 private->rdc_data.cu_model.model,
		 private->real_cyl,
		 private->rdc_data.trk_per_cyl,
		 private->rdc_data.sec_per_trk,
		 readonly ? ", read-only device" : "");
	return 0;

out_err3:
	dasd_alias_disconnect_device_from_lcu(device);
out_err2:
	dasd_free_block(device->block);
	device->block = NULL;
out_err1:
	kfree(private->conf_data);
	kfree(device->private);
	device->private = NULL;
	return rc;
}

static void dasd_eckd_uncheck_device(struct dasd_device *device)
{
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) device->private;
	dasd_alias_disconnect_device_from_lcu(device);
	private->ned = NULL;
	private->sneq = NULL;
	private->vdsneq = NULL;
	private->gneq = NULL;
	private->conf_len = 0;
	kfree(private->conf_data);
	private->conf_data = NULL;
}

static struct dasd_ccw_req *
dasd_eckd_analysis_ccw(struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	struct eckd_count *count_data;
	struct LO_eckd_data *LO_data;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	int cplength, datasize;
	int i;

	private = (struct dasd_eckd_private *) device->private;

	cplength = 8;
	datasize = sizeof(struct DE_eckd_data) + 2*sizeof(struct LO_eckd_data);
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize, device);
	if (IS_ERR(cqr))
		return cqr;
	ccw = cqr->cpaddr;
	/* Define extent for the first 3 tracks. */
	define_extent(ccw++, cqr->data, 0, 2,
		      DASD_ECKD_CCW_READ_COUNT, device);
	LO_data = cqr->data + sizeof(struct DE_eckd_data);
	/* Locate record for the first 4 records on track 0. */
	ccw[-1].flags |= CCW_FLAG_CC;
	locate_record(ccw++, LO_data++, 0, 0, 4,
		      DASD_ECKD_CCW_READ_COUNT, device, 0);

	count_data = private->count_area;
	for (i = 0; i < 4; i++) {
		ccw[-1].flags |= CCW_FLAG_CC;
		ccw->cmd_code = DASD_ECKD_CCW_READ_COUNT;
		ccw->flags = 0;
		ccw->count = 8;
		ccw->cda = (__u32)(addr_t) count_data;
		ccw++;
		count_data++;
	}

	/* Locate record for the first record on track 2. */
	ccw[-1].flags |= CCW_FLAG_CC;
	locate_record(ccw++, LO_data++, 2, 0, 1,
		      DASD_ECKD_CCW_READ_COUNT, device, 0);
	/* Read count ccw. */
	ccw[-1].flags |= CCW_FLAG_CC;
	ccw->cmd_code = DASD_ECKD_CCW_READ_COUNT;
	ccw->flags = 0;
	ccw->count = 8;
	ccw->cda = (__u32)(addr_t) count_data;

	cqr->block = NULL;
	cqr->startdev = device;
	cqr->memdev = device;
	cqr->retries = 255;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	return cqr;
}

/* differentiate between 'no record found' and any other error */
static int dasd_eckd_analysis_evaluation(struct dasd_ccw_req *init_cqr)
{
	char *sense;
	if (init_cqr->status == DASD_CQR_DONE)
		return INIT_CQR_OK;
	else if (init_cqr->status == DASD_CQR_NEED_ERP ||
		 init_cqr->status == DASD_CQR_FAILED) {
		sense = dasd_get_sense(&init_cqr->irb);
		if (sense && (sense[1] & SNS1_NO_REC_FOUND))
			return INIT_CQR_UNFORMATTED;
		else
			return INIT_CQR_ERROR;
	} else
		return INIT_CQR_ERROR;
}

/*
 * This is the callback function for the init_analysis cqr. It saves
 * the status of the initial analysis ccw before it frees it and kicks
 * the device to continue the startup sequence. This will call
 * dasd_eckd_do_analysis again (if the devices has not been marked
 * for deletion in the meantime).
 */
static void dasd_eckd_analysis_callback(struct dasd_ccw_req *init_cqr,
					void *data)
{
	struct dasd_eckd_private *private;
	struct dasd_device *device;

	device = init_cqr->startdev;
	private = (struct dasd_eckd_private *) device->private;
	private->init_cqr_status = dasd_eckd_analysis_evaluation(init_cqr);
	dasd_sfree_request(init_cqr, device);
	dasd_kick_device(device);
}

static int dasd_eckd_start_analysis(struct dasd_block *block)
{
	struct dasd_ccw_req *init_cqr;

	init_cqr = dasd_eckd_analysis_ccw(block->base);
	if (IS_ERR(init_cqr))
		return PTR_ERR(init_cqr);
	init_cqr->callback = dasd_eckd_analysis_callback;
	init_cqr->callback_data = NULL;
	init_cqr->expires = 5*HZ;
	/* first try without ERP, so we can later handle unformatted
	 * devices as special case
	 */
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &init_cqr->flags);
	init_cqr->retries = 0;
	dasd_add_request_head(init_cqr);
	return -EAGAIN;
}

static int dasd_eckd_end_analysis(struct dasd_block *block)
{
	struct dasd_device *device;
	struct dasd_eckd_private *private;
	struct eckd_count *count_area;
	unsigned int sb, blk_per_trk;
	int status, i;
	struct dasd_ccw_req *init_cqr;

	device = block->base;
	private = (struct dasd_eckd_private *) device->private;
	status = private->init_cqr_status;
	private->init_cqr_status = -1;
	if (status == INIT_CQR_ERROR) {
		/* try again, this time with full ERP */
		init_cqr = dasd_eckd_analysis_ccw(device);
		dasd_sleep_on(init_cqr);
		status = dasd_eckd_analysis_evaluation(init_cqr);
		dasd_sfree_request(init_cqr, device);
	}

	if (device->features & DASD_FEATURE_USERAW) {
		block->bp_block = DASD_RAW_BLOCKSIZE;
		blk_per_trk = DASD_RAW_BLOCK_PER_TRACK;
		block->s2b_shift = 3;
		goto raw;
	}

	if (status == INIT_CQR_UNFORMATTED) {
		dev_warn(&device->cdev->dev, "The DASD is not formatted\n");
		return -EMEDIUMTYPE;
	} else if (status == INIT_CQR_ERROR) {
		dev_err(&device->cdev->dev,
			"Detecting the DASD disk layout failed because "
			"of an I/O error\n");
		return -EIO;
	}

	private->uses_cdl = 1;
	/* Check Track 0 for Compatible Disk Layout */
	count_area = NULL;
	for (i = 0; i < 3; i++) {
		if (private->count_area[i].kl != 4 ||
		    private->count_area[i].dl != dasd_eckd_cdl_reclen(i) - 4) {
			private->uses_cdl = 0;
			break;
		}
	}
	if (i == 3)
		count_area = &private->count_area[4];

	if (private->uses_cdl == 0) {
		for (i = 0; i < 5; i++) {
			if ((private->count_area[i].kl != 0) ||
			    (private->count_area[i].dl !=
			     private->count_area[0].dl))
				break;
		}
		if (i == 5)
			count_area = &private->count_area[0];
	} else {
		if (private->count_area[3].record == 1)
			dev_warn(&device->cdev->dev,
				 "Track 0 has no records following the VTOC\n");
	}

	if (count_area != NULL && count_area->kl == 0) {
		/* we found notthing violating our disk layout */
		if (dasd_check_blocksize(count_area->dl) == 0)
			block->bp_block = count_area->dl;
	}
	if (block->bp_block == 0) {
		dev_warn(&device->cdev->dev,
			 "The disk layout of the DASD is not supported\n");
		return -EMEDIUMTYPE;
	}
	block->s2b_shift = 0;	/* bits to shift 512 to get a block */
	for (sb = 512; sb < block->bp_block; sb = sb << 1)
		block->s2b_shift++;

	blk_per_trk = recs_per_track(&private->rdc_data, 0, block->bp_block);

raw:
	block->blocks = (private->real_cyl *
			  private->rdc_data.trk_per_cyl *
			  blk_per_trk);

	dev_info(&device->cdev->dev,
		 "DASD with %d KB/block, %d KB total size, %d KB/track, "
		 "%s\n", (block->bp_block >> 10),
		 ((private->real_cyl *
		   private->rdc_data.trk_per_cyl *
		   blk_per_trk * (block->bp_block >> 9)) >> 1),
		 ((blk_per_trk * block->bp_block) >> 10),
		 private->uses_cdl ?
		 "compatible disk layout" : "linux disk layout");

	return 0;
}

static int dasd_eckd_do_analysis(struct dasd_block *block)
{
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) block->base->private;
	if (private->init_cqr_status < 0)
		return dasd_eckd_start_analysis(block);
	else
		return dasd_eckd_end_analysis(block);
}

static int dasd_eckd_ready_to_online(struct dasd_device *device)
{
	return dasd_alias_add_device(device);
};

static int dasd_eckd_online_to_ready(struct dasd_device *device)
{
	cancel_work_sync(&device->reload_device);
	cancel_work_sync(&device->kick_validate);
	return dasd_alias_remove_device(device);
};

static int
dasd_eckd_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
{
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) block->base->private;
	if (dasd_check_blocksize(block->bp_block) == 0) {
		geo->sectors = recs_per_track(&private->rdc_data,
					      0, block->bp_block);
	}
	geo->cylinders = private->rdc_data.no_cyl;
	geo->heads = private->rdc_data.trk_per_cyl;
	return 0;
}

static struct dasd_ccw_req *
dasd_eckd_format_device(struct dasd_device * device,
			struct format_data_t * fdata)
{
	struct dasd_eckd_private *private;
	struct dasd_ccw_req *fcp;
	struct eckd_count *ect;
	struct ccw1 *ccw;
	void *data;
	int rpt;
	struct ch_t address;
	int cplength, datasize;
	int i;
	int intensity = 0;
	int r0_perm;

	private = (struct dasd_eckd_private *) device->private;
	rpt = recs_per_track(&private->rdc_data, 0, fdata->blksize);
	set_ch_t(&address,
		 fdata->start_unit / private->rdc_data.trk_per_cyl,
		 fdata->start_unit % private->rdc_data.trk_per_cyl);

	/* Sanity checks. */
	if (fdata->start_unit >=
	    (private->real_cyl * private->rdc_data.trk_per_cyl)) {
		dev_warn(&device->cdev->dev, "Start track number %d used in "
			 "formatting is too big\n", fdata->start_unit);
		return ERR_PTR(-EINVAL);
	}
	if (fdata->start_unit > fdata->stop_unit) {
		dev_warn(&device->cdev->dev, "Start track %d used in "
			 "formatting exceeds end track\n", fdata->start_unit);
		return ERR_PTR(-EINVAL);
	}
	if (dasd_check_blocksize(fdata->blksize) != 0) {
		dev_warn(&device->cdev->dev,
			 "The DASD cannot be formatted with block size %d\n",
			 fdata->blksize);
		return ERR_PTR(-EINVAL);
	}

	/*
	 * fdata->intensity is a bit string that tells us what to do:
	 *   Bit 0: write record zero
	 *   Bit 1: write home address, currently not supported
	 *   Bit 2: invalidate tracks
	 *   Bit 3: use OS/390 compatible disk layout (cdl)
	 *   Bit 4: do not allow storage subsystem to modify record zero
	 * Only some bit combinations do make sense.
	 */
	if (fdata->intensity & 0x10) {
		r0_perm = 0;
		intensity = fdata->intensity & ~0x10;
	} else {
		r0_perm = 1;
		intensity = fdata->intensity;
	}
	switch (intensity) {
	case 0x00:	/* Normal format */
	case 0x08:	/* Normal format, use cdl. */
		cplength = 2 + rpt;
		datasize = sizeof(struct DE_eckd_data) +
			sizeof(struct LO_eckd_data) +
			rpt * sizeof(struct eckd_count);
		break;
	case 0x01:	/* Write record zero and format track. */
	case 0x09:	/* Write record zero and format track, use cdl. */
		cplength = 3 + rpt;
		datasize = sizeof(struct DE_eckd_data) +
			sizeof(struct LO_eckd_data) +
			sizeof(struct eckd_count) +
			rpt * sizeof(struct eckd_count);
		break;
	case 0x04:	/* Invalidate track. */
	case 0x0c:	/* Invalidate track, use cdl. */
		cplength = 3;
		datasize = sizeof(struct DE_eckd_data) +
			sizeof(struct LO_eckd_data) +
			sizeof(struct eckd_count);
		break;
	default:
		dev_warn(&device->cdev->dev, "An I/O control call used "
			 "incorrect flags 0x%x\n", fdata->intensity);
		return ERR_PTR(-EINVAL);
	}
	/* Allocate the format ccw request. */
	fcp = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize, device);
	if (IS_ERR(fcp))
		return fcp;

	data = fcp->data;
	ccw = fcp->cpaddr;

	switch (intensity & ~0x08) {
	case 0x00: /* Normal format. */
		define_extent(ccw++, (struct DE_eckd_data *) data,
			      fdata->start_unit, fdata->start_unit,
			      DASD_ECKD_CCW_WRITE_CKD, device);
		/* grant subsystem permission to format R0 */
		if (r0_perm)
			((struct DE_eckd_data *)data)->ga_extended |= 0x04;
		data += sizeof(struct DE_eckd_data);
		ccw[-1].flags |= CCW_FLAG_CC;
		locate_record(ccw++, (struct LO_eckd_data *) data,
			      fdata->start_unit, 0, rpt,
			      DASD_ECKD_CCW_WRITE_CKD, device,
			      fdata->blksize);
		data += sizeof(struct LO_eckd_data);
		break;
	case 0x01: /* Write record zero + format track. */
		define_extent(ccw++, (struct DE_eckd_data *) data,
			      fdata->start_unit, fdata->start_unit,
			      DASD_ECKD_CCW_WRITE_RECORD_ZERO,
			      device);
		data += sizeof(struct DE_eckd_data);
		ccw[-1].flags |= CCW_FLAG_CC;
		locate_record(ccw++, (struct LO_eckd_data *) data,
			      fdata->start_unit, 0, rpt + 1,
			      DASD_ECKD_CCW_WRITE_RECORD_ZERO, device,
			      device->block->bp_block);
		data += sizeof(struct LO_eckd_data);
		break;
	case 0x04: /* Invalidate track. */
		define_extent(ccw++, (struct DE_eckd_data *) data,
			      fdata->start_unit, fdata->start_unit,
			      DASD_ECKD_CCW_WRITE_CKD, device);
		data += sizeof(struct DE_eckd_data);
		ccw[-1].flags |= CCW_FLAG_CC;
		locate_record(ccw++, (struct LO_eckd_data *) data,
			      fdata->start_unit, 0, 1,
			      DASD_ECKD_CCW_WRITE_CKD, device, 8);
		data += sizeof(struct LO_eckd_data);
		break;
	}
	if (intensity & 0x01) {	/* write record zero */
		ect = (struct eckd_count *) data;
		data += sizeof(struct eckd_count);
		ect->cyl = address.cyl;
		ect->head = address.head;
		ect->record = 0;
		ect->kl = 0;
		ect->dl = 8;
		ccw[-1].flags |= CCW_FLAG_CC;
		ccw->cmd_code = DASD_ECKD_CCW_WRITE_RECORD_ZERO;
		ccw->flags = CCW_FLAG_SLI;
		ccw->count = 8;
		ccw->cda = (__u32)(addr_t) ect;
		ccw++;
	}
	if ((intensity & ~0x08) & 0x04) {	/* erase track */
		ect = (struct eckd_count *) data;
		data += sizeof(struct eckd_count);
		ect->cyl = address.cyl;
		ect->head = address.head;
		ect->record = 1;
		ect->kl = 0;
		ect->dl = 0;
		ccw[-1].flags |= CCW_FLAG_CC;
		ccw->cmd_code = DASD_ECKD_CCW_WRITE_CKD;
		ccw->flags = CCW_FLAG_SLI;
		ccw->count = 8;
		ccw->cda = (__u32)(addr_t) ect;
	} else {		/* write remaining records */
		for (i = 0; i < rpt; i++) {
			ect = (struct eckd_count *) data;
			data += sizeof(struct eckd_count);
			ect->cyl = address.cyl;
			ect->head = address.head;
			ect->record = i + 1;
			ect->kl = 0;
			ect->dl = fdata->blksize;
			/* Check for special tracks 0-1 when formatting CDL */
			if ((intensity & 0x08) &&
			    fdata->start_unit == 0) {
				if (i < 3) {
					ect->kl = 4;
					ect->dl = sizes_trk0[i] - 4;
				}
			}
			if ((intensity & 0x08) &&
			    fdata->start_unit == 1) {
				ect->kl = 44;
				ect->dl = LABEL_SIZE - 44;
			}
			ccw[-1].flags |= CCW_FLAG_CC;
			ccw->cmd_code = DASD_ECKD_CCW_WRITE_CKD;
			ccw->flags = CCW_FLAG_SLI;
			ccw->count = 8;
			ccw->cda = (__u32)(addr_t) ect;
			ccw++;
		}
	}
	fcp->startdev = device;
	fcp->memdev = device;
	fcp->retries = 256;
	fcp->buildclk = get_clock();
	fcp->status = DASD_CQR_FILLED;
	return fcp;
}

static void dasd_eckd_handle_terminated_request(struct dasd_ccw_req *cqr)
{
	cqr->status = DASD_CQR_FILLED;
	if (cqr->block && (cqr->startdev != cqr->block->base)) {
		dasd_eckd_reset_ccw_to_base_io(cqr);
		cqr->startdev = cqr->block->base;
		cqr->lpm = cqr->block->base->path_data.opm;
	}
};

static dasd_erp_fn_t
dasd_eckd_erp_action(struct dasd_ccw_req * cqr)
{
	struct dasd_device *device = (struct dasd_device *) cqr->startdev;
	struct ccw_device *cdev = device->cdev;

	switch (cdev->id.cu_type) {
	case 0x3990:
	case 0x2105:
	case 0x2107:
	case 0x1750:
		return dasd_3990_erp_action;
	case 0x9343:
	case 0x3880:
	default:
		return dasd_default_erp_action;
	}
}

static dasd_erp_fn_t
dasd_eckd_erp_postaction(struct dasd_ccw_req * cqr)
{
	return dasd_default_erp_postaction;
}

static void dasd_eckd_check_for_device_change(struct dasd_device *device,
					      struct dasd_ccw_req *cqr,
					      struct irb *irb)
{
	char mask;
	char *sense = NULL;
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) device->private;
	/* first of all check for state change pending interrupt */
	mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
	if ((scsw_dstat(&irb->scsw) & mask) == mask) {
		/*
		 * for alias only, not in offline processing
		 * and only if not suspended
		 */
		if (!device->block && private->lcu &&
		    device->state == DASD_STATE_ONLINE &&
		    !test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
		    !test_bit(DASD_FLAG_SUSPENDED, &device->flags)) {
			/*
			 * the state change could be caused by an alias
			 * reassignment remove device from alias handling
			 * to prevent new requests from being scheduled on
			 * the wrong alias device
			 */
			dasd_alias_remove_device(device);

			/* schedule worker to reload device */
			dasd_reload_device(device);
		}
		dasd_generic_handle_state_change(device);
		return;
	}

	sense = dasd_get_sense(irb);
	if (!sense)
		return;

	/* summary unit check */
	if ((sense[27] & DASD_SENSE_BIT_0) && (sense[7] == 0x0D) &&
	    (scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK)) {
		dasd_alias_handle_summary_unit_check(device, irb);
		return;
	}

	/* service information message SIM */
	if (!cqr && !(sense[27] & DASD_SENSE_BIT_0) &&
	    ((sense[6] & DASD_SIM_SENSE) == DASD_SIM_SENSE)) {
		dasd_3990_erp_handle_sim(device, sense);
		return;
	}

	/* loss of device reservation is handled via base devices only
	 * as alias devices may be used with several bases
	 */
	if (device->block && (sense[27] & DASD_SENSE_BIT_0) &&
	    (sense[7] == 0x3F) &&
	    (scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
	    test_bit(DASD_FLAG_IS_RESERVED, &device->flags)) {
		if (device->features & DASD_FEATURE_FAILONSLCK)
			set_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
		clear_bit(DASD_FLAG_IS_RESERVED, &device->flags);
		dev_err(&device->cdev->dev,
			"The device reservation was lost\n");
	}
}

static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single(
					       struct dasd_device *startdev,
					       struct dasd_block *block,
					       struct request *req,
					       sector_t first_rec,
					       sector_t last_rec,
					       sector_t first_trk,
					       sector_t last_trk,
					       unsigned int first_offs,
					       unsigned int last_offs,
					       unsigned int blk_per_trk,
					       unsigned int blksize)
{
	struct dasd_eckd_private *private;
	unsigned long *idaws;
	struct LO_eckd_data *LO_data;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	struct req_iterator iter;
	struct bio_vec *bv;
	char *dst;
	unsigned int off;
	int count, cidaw, cplength, datasize;
	sector_t recid;
	unsigned char cmd, rcmd;
	int use_prefix;
	struct dasd_device *basedev;

	basedev = block->base;
	private = (struct dasd_eckd_private *) basedev->private;
	if (rq_data_dir(req) == READ)
		cmd = DASD_ECKD_CCW_READ_MT;
	else if (rq_data_dir(req) == WRITE)
		cmd = DASD_ECKD_CCW_WRITE_MT;
	else
		return ERR_PTR(-EINVAL);

	/* Check struct bio and count the number of blocks for the request. */
	count = 0;
	cidaw = 0;
	rq_for_each_segment(bv, req, iter) {
		if (bv->bv_len & (blksize - 1))
			/* Eckd can only do full blocks. */
			return ERR_PTR(-EINVAL);
		count += bv->bv_len >> (block->s2b_shift + 9);
#if defined(CONFIG_64BIT)
		if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
			cidaw += bv->bv_len >> (block->s2b_shift + 9);
#endif
	}
	/* Paranoia. */
	if (count != last_rec - first_rec + 1)
		return ERR_PTR(-EINVAL);

	/* use the prefix command if available */
	use_prefix = private->features.feature[8] & 0x01;
	if (use_prefix) {
		/* 1x prefix + number of blocks */
		cplength = 2 + count;
		/* 1x prefix + cidaws*sizeof(long) */
		datasize = sizeof(struct PFX_eckd_data) +
			sizeof(struct LO_eckd_data) +
			cidaw * sizeof(unsigned long);
	} else {
		/* 1x define extent + 1x locate record + number of blocks */
		cplength = 2 + count;
		/* 1x define extent + 1x locate record + cidaws*sizeof(long) */
		datasize = sizeof(struct DE_eckd_data) +
			sizeof(struct LO_eckd_data) +
			cidaw * sizeof(unsigned long);
	}
	/* Find out the number of additional locate record ccws for cdl. */
	if (private->uses_cdl && first_rec < 2*blk_per_trk) {
		if (last_rec >= 2*blk_per_trk)
			count = 2*blk_per_trk - first_rec;
		cplength += count;
		datasize += count*sizeof(struct LO_eckd_data);
	}
	/* Allocate the ccw request. */
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize,
				   startdev);
	if (IS_ERR(cqr))
		return cqr;
	ccw = cqr->cpaddr;
	/* First ccw is define extent or prefix. */
	if (use_prefix) {
		if (prefix(ccw++, cqr->data, first_trk,
			   last_trk, cmd, basedev, startdev) == -EAGAIN) {
			/* Clock not in sync and XRC is enabled.
			 * Try again later.
			 */
			dasd_sfree_request(cqr, startdev);
			return ERR_PTR(-EAGAIN);
		}
		idaws = (unsigned long *) (cqr->data +
					   sizeof(struct PFX_eckd_data));
	} else {
		if (define_extent(ccw++, cqr->data, first_trk,
				  last_trk, cmd, basedev) == -EAGAIN) {
			/* Clock not in sync and XRC is enabled.
			 * Try again later.
			 */
			dasd_sfree_request(cqr, startdev);
			return ERR_PTR(-EAGAIN);
		}
		idaws = (unsigned long *) (cqr->data +
					   sizeof(struct DE_eckd_data));
	}
	/* Build locate_record+read/write/ccws. */
	LO_data = (struct LO_eckd_data *) (idaws + cidaw);
	recid = first_rec;
	if (private->uses_cdl == 0 || recid > 2*blk_per_trk) {
		/* Only standard blocks so there is just one locate record. */
		ccw[-1].flags |= CCW_FLAG_CC;
		locate_record(ccw++, LO_data++, first_trk, first_offs + 1,
			      last_rec - recid + 1, cmd, basedev, blksize);
	}
	rq_for_each_segment(bv, req, iter) {
		dst = page_address(bv->bv_page) + bv->bv_offset;
		if (dasd_page_cache) {
			char *copy = kmem_cache_alloc(dasd_page_cache,
						      GFP_DMA | __GFP_NOWARN);
			if (copy && rq_data_dir(req) == WRITE)
				memcpy(copy + bv->bv_offset, dst, bv->bv_len);
			if (copy)
				dst = copy + bv->bv_offset;
		}
		for (off = 0; off < bv->bv_len; off += blksize) {
			sector_t trkid = recid;
			unsigned int recoffs = sector_div(trkid, blk_per_trk);
			rcmd = cmd;
			count = blksize;
			/* Locate record for cdl special block ? */
			if (private->uses_cdl && recid < 2*blk_per_trk) {
				if (dasd_eckd_cdl_special(blk_per_trk, recid)){
					rcmd |= 0x8;
					count = dasd_eckd_cdl_reclen(recid);
					if (count < blksize &&
					    rq_data_dir(req) == READ)
						memset(dst + count, 0xe5,
						       blksize - count);
				}
				ccw[-1].flags |= CCW_FLAG_CC;
				locate_record(ccw++, LO_data++,
					      trkid, recoffs + 1,
					      1, rcmd, basedev, count);
			}
			/* Locate record for standard blocks ? */
			if (private->uses_cdl && recid == 2*blk_per_trk) {
				ccw[-1].flags |= CCW_FLAG_CC;
				locate_record(ccw++, LO_data++,
					      trkid, recoffs + 1,
					      last_rec - recid + 1,
					      cmd, basedev, count);
			}
			/* Read/write ccw. */
			ccw[-1].flags |= CCW_FLAG_CC;
			ccw->cmd_code = rcmd;
			ccw->count = count;
			if (idal_is_needed(dst, blksize)) {
				ccw->cda = (__u32)(addr_t) idaws;
				ccw->flags = CCW_FLAG_IDA;
				idaws = idal_create_words(idaws, dst, blksize);
			} else {
				ccw->cda = (__u32)(addr_t) dst;
				ccw->flags = 0;
			}
			ccw++;
			dst += blksize;
			recid++;
		}
	}
	if (blk_noretry_request(req) ||
	    block->base->features & DASD_FEATURE_FAILFAST)
		set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->startdev = startdev;
	cqr->memdev = startdev;
	cqr->block = block;
	cqr->expires = startdev->default_expires * HZ;	/* default 5 minutes */
	cqr->lpm = startdev->path_data.ppm;
	cqr->retries = 256;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	return cqr;
}

static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_track(
					       struct dasd_device *startdev,
					       struct dasd_block *block,
					       struct request *req,
					       sector_t first_rec,
					       sector_t last_rec,
					       sector_t first_trk,
					       sector_t last_trk,
					       unsigned int first_offs,
					       unsigned int last_offs,
					       unsigned int blk_per_trk,
					       unsigned int blksize)
{
	unsigned long *idaws;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	struct req_iterator iter;
	struct bio_vec *bv;
	char *dst, *idaw_dst;
	unsigned int cidaw, cplength, datasize;
	unsigned int tlf;
	sector_t recid;
	unsigned char cmd;
	struct dasd_device *basedev;
	unsigned int trkcount, count, count_to_trk_end;
	unsigned int idaw_len, seg_len, part_len, len_to_track_end;
	unsigned char new_track, end_idaw;
	sector_t trkid;
	unsigned int recoffs;

	basedev = block->base;
	if (rq_data_dir(req) == READ)
		cmd = DASD_ECKD_CCW_READ_TRACK_DATA;
	else if (rq_data_dir(req) == WRITE)
		cmd = DASD_ECKD_CCW_WRITE_TRACK_DATA;
	else
		return ERR_PTR(-EINVAL);

	/* Track based I/O needs IDAWs for each page, and not just for
	 * 64 bit addresses. We need additional idals for pages
	 * that get filled from two tracks, so we use the number
	 * of records as upper limit.
	 */
	cidaw = last_rec - first_rec + 1;
	trkcount = last_trk - first_trk + 1;

	/* 1x prefix + one read/write ccw per track */
	cplength = 1 + trkcount;

	/* on 31-bit we need space for two 32 bit addresses per page
	 * on 64-bit one 64 bit address
	 */
	datasize = sizeof(struct PFX_eckd_data) +
		cidaw * sizeof(unsigned long long);

	/* Allocate the ccw request. */
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength, datasize,
				   startdev);
	if (IS_ERR(cqr))
		return cqr;
	ccw = cqr->cpaddr;
	/* transfer length factor: how many bytes to read from the last track */
	if (first_trk == last_trk)
		tlf = last_offs - first_offs + 1;
	else
		tlf = last_offs + 1;
	tlf *= blksize;

	if (prefix_LRE(ccw++, cqr->data, first_trk,
		       last_trk, cmd, basedev, startdev,
		       1 /* format */, first_offs + 1,
		       trkcount, blksize,
		       tlf) == -EAGAIN) {
		/* Clock not in sync and XRC is enabled.
		 * Try again later.
		 */
		dasd_sfree_request(cqr, startdev);
		return ERR_PTR(-EAGAIN);
	}

	/*
	 * The translation of request into ccw programs must meet the
	 * following conditions:
	 * - all idaws but the first and the last must address full pages
	 *   (or 2K blocks on 31-bit)
	 * - the scope of a ccw and it's idal ends with the track boundaries
	 */
	idaws = (unsigned long *) (cqr->data + sizeof(struct PFX_eckd_data));
	recid = first_rec;
	new_track = 1;
	end_idaw = 0;
	len_to_track_end = 0;
	idaw_dst = NULL;
	idaw_len = 0;
	rq_for_each_segment(bv, req, iter) {
		dst = page_address(bv->bv_page) + bv->bv_offset;
		seg_len = bv->bv_len;
		while (seg_len) {
			if (new_track) {
				trkid = recid;
				recoffs = sector_div(trkid, blk_per_trk);
				count_to_trk_end = blk_per_trk - recoffs;
				count = min((last_rec - recid + 1),
					    (sector_t)count_to_trk_end);
				len_to_track_end = count * blksize;
				ccw[-1].flags |= CCW_FLAG_CC;
				ccw->cmd_code = cmd;
				ccw->count = len_to_track_end;
				ccw->cda = (__u32)(addr_t)idaws;
				ccw->flags = CCW_FLAG_IDA;
				ccw++;
				recid += count;
				new_track = 0;
				/* first idaw for a ccw may start anywhere */
				if (!idaw_dst)
					idaw_dst = dst;
			}
			/* If we start a new idaw, we must make sure that it
			 * starts on an IDA_BLOCK_SIZE boundary.
			 * If we continue an idaw, we must make sure that the
			 * current segment begins where the so far accumulated
			 * idaw ends
			 */
			if (!idaw_dst) {
				if (__pa(dst) & (IDA_BLOCK_SIZE-1)) {
					dasd_sfree_request(cqr, startdev);
					return ERR_PTR(-ERANGE);
				} else
					idaw_dst = dst;
			}
			if ((idaw_dst + idaw_len) != dst) {
				dasd_sfree_request(cqr, startdev);
				return ERR_PTR(-ERANGE);
			}
			part_len = min(seg_len, len_to_track_end);
			seg_len -= part_len;
			dst += part_len;
			idaw_len += part_len;
			len_to_track_end -= part_len;
			/* collected memory area ends on an IDA_BLOCK border,
			 * -> create an idaw
			 * idal_create_words will handle cases where idaw_len
			 * is larger then IDA_BLOCK_SIZE
			 */
			if (!(__pa(idaw_dst + idaw_len) & (IDA_BLOCK_SIZE-1)))
				end_idaw = 1;
			/* We also need to end the idaw at track end */
			if (!len_to_track_end) {
				new_track = 1;
				end_idaw = 1;
			}
			if (end_idaw) {
				idaws = idal_create_words(idaws, idaw_dst,
							  idaw_len);
				idaw_dst = NULL;
				idaw_len = 0;
				end_idaw = 0;
			}
		}
	}

	if (blk_noretry_request(req) ||
	    block->base->features & DASD_FEATURE_FAILFAST)
		set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->startdev = startdev;
	cqr->memdev = startdev;
	cqr->block = block;
	cqr->expires = startdev->default_expires * HZ;	/* default 5 minutes */
	cqr->lpm = startdev->path_data.ppm;
	cqr->retries = 256;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	return cqr;
}

static int prepare_itcw(struct itcw *itcw,
			unsigned int trk, unsigned int totrk, int cmd,
			struct dasd_device *basedev,
			struct dasd_device *startdev,
			unsigned int rec_on_trk, int count,
			unsigned int blksize,
			unsigned int total_data_size,
			unsigned int tlf,
			unsigned int blk_per_trk)
{
	struct PFX_eckd_data pfxdata;
	struct dasd_eckd_private *basepriv, *startpriv;
	struct DE_eckd_data *dedata;
	struct LRE_eckd_data *lredata;
	struct dcw *dcw;

	u32 begcyl, endcyl;
	u16 heads, beghead, endhead;
	u8 pfx_cmd;

	int rc = 0;
	int sector = 0;
	int dn, d;


	/* setup prefix data */
	basepriv = (struct dasd_eckd_private *) basedev->private;
	startpriv = (struct dasd_eckd_private *) startdev->private;
	dedata = &pfxdata.define_extent;
	lredata = &pfxdata.locate_record;

	memset(&pfxdata, 0, sizeof(pfxdata));
	pfxdata.format = 1; /* PFX with LRE */
	pfxdata.base_address = basepriv->ned->unit_addr;
	pfxdata.base_lss = basepriv->ned->ID;
	pfxdata.validity.define_extent = 1;

	/* private uid is kept up to date, conf_data may be outdated */
	if (startpriv->uid.type != UA_BASE_DEVICE) {
		pfxdata.validity.verify_base = 1;
		if (startpriv->uid.type == UA_HYPER_PAV_ALIAS)
			pfxdata.validity.hyper_pav = 1;
	}

	switch (cmd) {
	case DASD_ECKD_CCW_READ_TRACK_DATA:
		dedata->mask.perm = 0x1;
		dedata->attributes.operation = basepriv->attrib.operation;
		dedata->blk_size = blksize;
		dedata->ga_extended |= 0x42;
		lredata->operation.orientation = 0x0;
		lredata->operation.operation = 0x0C;
		lredata->auxiliary.check_bytes = 0x01;
		pfx_cmd = DASD_ECKD_CCW_PFX_READ;
		break;
	case DASD_ECKD_CCW_WRITE_TRACK_DATA:
		dedata->mask.perm = 0x02;
		dedata->attributes.operation = basepriv->attrib.operation;
		dedata->blk_size = blksize;
		rc = check_XRC_on_prefix(&pfxdata, basedev);
		dedata->ga_extended |= 0x42;
		lredata->operation.orientation = 0x0;
		lredata->operation.operation = 0x3F;
		lredata->extended_operation = 0x23;
		lredata->auxiliary.check_bytes = 0x2;
		pfx_cmd = DASD_ECKD_CCW_PFX;
		break;
	default:
		DBF_DEV_EVENT(DBF_ERR, basedev,
			      "prepare itcw, unknown opcode 0x%x", cmd);
		BUG();
		break;
	}
	if (rc)
		return rc;

	dedata->attributes.mode = 0x3;	/* ECKD */

	heads = basepriv->rdc_data.trk_per_cyl;
	begcyl = trk / heads;
	beghead = trk % heads;
	endcyl = totrk / heads;
	endhead = totrk % heads;

	/* check for sequential prestage - enhance cylinder range */
	if (dedata->attributes.operation == DASD_SEQ_PRESTAGE ||
	    dedata->attributes.operation == DASD_SEQ_ACCESS) {

		if (endcyl + basepriv->attrib.nr_cyl < basepriv->real_cyl)
			endcyl += basepriv->attrib.nr_cyl;
		else
			endcyl = (basepriv->real_cyl - 1);
	}

	set_ch_t(&dedata->beg_ext, begcyl, beghead);
	set_ch_t(&dedata->end_ext, endcyl, endhead);

	dedata->ep_format = 0x20; /* records per track is valid */
	dedata->ep_rec_per_track = blk_per_trk;

	if (rec_on_trk) {
		switch (basepriv->rdc_data.dev_type) {
		case 0x3390:
			dn = ceil_quot(blksize + 6, 232);
			d = 9 + ceil_quot(blksize + 6 * (dn + 1), 34);
			sector = (49 + (rec_on_trk - 1) * (10 + d)) / 8;
			break;
		case 0x3380:
			d = 7 + ceil_quot(blksize + 12, 32);
			sector = (39 + (rec_on_trk - 1) * (8 + d)) / 7;
			break;
		}
	}

	lredata->auxiliary.length_valid = 1;
	lredata->auxiliary.length_scope = 1;
	lredata->auxiliary.imbedded_ccw_valid = 1;
	lredata->length = tlf;
	lredata->imbedded_ccw = cmd;
	lredata->count = count;
	lredata->sector = sector;
	set_ch_t(&lredata->seek_addr, begcyl, beghead);
	lredata->search_arg.cyl = lredata->seek_addr.cyl;
	lredata->search_arg.head = lredata->seek_addr.head;
	lredata->search_arg.record = rec_on_trk;

	dcw = itcw_add_dcw(itcw, pfx_cmd, 0,
		     &pfxdata, sizeof(pfxdata), total_data_size);
	return IS_ERR(dcw) ? PTR_ERR(dcw) : 0;
}

static struct dasd_ccw_req *dasd_eckd_build_cp_tpm_track(
					       struct dasd_device *startdev,
					       struct dasd_block *block,
					       struct request *req,
					       sector_t first_rec,
					       sector_t last_rec,
					       sector_t first_trk,
					       sector_t last_trk,
					       unsigned int first_offs,
					       unsigned int last_offs,
					       unsigned int blk_per_trk,
					       unsigned int blksize)
{
	struct dasd_ccw_req *cqr;
	struct req_iterator iter;
	struct bio_vec *bv;
	char *dst;
	unsigned int trkcount, ctidaw;
	unsigned char cmd;
	struct dasd_device *basedev;
	unsigned int tlf;
	struct itcw *itcw;
	struct tidaw *last_tidaw = NULL;
	int itcw_op;
	size_t itcw_size;
	u8 tidaw_flags;
	unsigned int seg_len, part_len, len_to_track_end;
	unsigned char new_track;
	sector_t recid, trkid;
	unsigned int offs;
	unsigned int count, count_to_trk_end;
	int ret;

	basedev = block->base;
	if (rq_data_dir(req) == READ) {
		cmd = DASD_ECKD_CCW_READ_TRACK_DATA;
		itcw_op = ITCW_OP_READ;
	} else if (rq_data_dir(req) == WRITE) {
		cmd = DASD_ECKD_CCW_WRITE_TRACK_DATA;
		itcw_op = ITCW_OP_WRITE;
	} else
		return ERR_PTR(-EINVAL);

	/* trackbased I/O needs address all memory via TIDAWs,
	 * not just for 64 bit addresses. This allows us to map
	 * each segment directly to one tidaw.
	 * In the case of write requests, additional tidaws may
	 * be needed when a segment crosses a track boundary.
	 */
	trkcount = last_trk - first_trk + 1;
	ctidaw = 0;
	rq_for_each_segment(bv, req, iter) {
		++ctidaw;
	}
	if (rq_data_dir(req) == WRITE)
		ctidaw += (last_trk - first_trk);

	/* Allocate the ccw request. */
	itcw_size = itcw_calc_size(0, ctidaw, 0);
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 0, itcw_size, startdev);
	if (IS_ERR(cqr))
		return cqr;

	/* transfer length factor: how many bytes to read from the last track */
	if (first_trk == last_trk)
		tlf = last_offs - first_offs + 1;
	else
		tlf = last_offs + 1;
	tlf *= blksize;

	itcw = itcw_init(cqr->data, itcw_size, itcw_op, 0, ctidaw, 0);
	if (IS_ERR(itcw)) {
		ret = -EINVAL;
		goto out_error;
	}
	cqr->cpaddr = itcw_get_tcw(itcw);
	if (prepare_itcw(itcw, first_trk, last_trk,
			 cmd, basedev, startdev,
			 first_offs + 1,
			 trkcount, blksize,
			 (last_rec - first_rec + 1) * blksize,
			 tlf, blk_per_trk) == -EAGAIN) {
		/* Clock not in sync and XRC is enabled.
		 * Try again later.
		 */
		ret = -EAGAIN;
		goto out_error;
	}
	len_to_track_end = 0;
	/*
	 * A tidaw can address 4k of memory, but must not cross page boundaries
	 * We can let the block layer handle this by setting
	 * blk_queue_segment_boundary to page boundaries and
	 * blk_max_segment_size to page size when setting up the request queue.
	 * For write requests, a TIDAW must not cross track boundaries, because
	 * we have to set the CBC flag on the last tidaw for each track.
	 */
	if (rq_data_dir(req) == WRITE) {
		new_track = 1;
		recid = first_rec;
		rq_for_each_segment(bv, req, iter) {
			dst = page_address(bv->bv_page) + bv->bv_offset;
			seg_len = bv->bv_len;
			while (seg_len) {
				if (new_track) {
					trkid = recid;
					offs = sector_div(trkid, blk_per_trk);
					count_to_trk_end = blk_per_trk - offs;
					count = min((last_rec - recid + 1),
						    (sector_t)count_to_trk_end);
					len_to_track_end = count * blksize;
					recid += count;
					new_track = 0;
				}
				part_len = min(seg_len, len_to_track_end);
				seg_len -= part_len;
				len_to_track_end -= part_len;
				/* We need to end the tidaw at track end */
				if (!len_to_track_end) {
					new_track = 1;
					tidaw_flags = TIDAW_FLAGS_INSERT_CBC;
				} else
					tidaw_flags = 0;
				last_tidaw = itcw_add_tidaw(itcw, tidaw_flags,
							    dst, part_len);
				if (IS_ERR(last_tidaw)) {
					ret = -EINVAL;
					goto out_error;
				}
				dst += part_len;
			}
		}
	} else {
		rq_for_each_segment(bv, req, iter) {
			dst = page_address(bv->bv_page) + bv->bv_offset;
			last_tidaw = itcw_add_tidaw(itcw, 0x00,
						    dst, bv->bv_len);
			if (IS_ERR(last_tidaw)) {
				ret = -EINVAL;
				goto out_error;
			}
		}
	}
	last_tidaw->flags |= TIDAW_FLAGS_LAST;
	last_tidaw->flags &= ~TIDAW_FLAGS_INSERT_CBC;
	itcw_finalize(itcw);

	if (blk_noretry_request(req) ||
	    block->base->features & DASD_FEATURE_FAILFAST)
		set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->cpmode = 1;
	cqr->startdev = startdev;
	cqr->memdev = startdev;
	cqr->block = block;
	cqr->expires = startdev->default_expires * HZ;	/* default 5 minutes */
	cqr->lpm = startdev->path_data.ppm;
	cqr->retries = 256;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	return cqr;
out_error:
	dasd_sfree_request(cqr, startdev);
	return ERR_PTR(ret);
}

static struct dasd_ccw_req *dasd_eckd_build_cp(struct dasd_device *startdev,
					       struct dasd_block *block,
					       struct request *req)
{
	int cmdrtd, cmdwtd;
	int use_prefix;
	int fcx_multitrack;
	struct dasd_eckd_private *private;
	struct dasd_device *basedev;
	sector_t first_rec, last_rec;
	sector_t first_trk, last_trk;
	unsigned int first_offs, last_offs;
	unsigned int blk_per_trk, blksize;
	int cdlspecial;
	unsigned int data_size;
	struct dasd_ccw_req *cqr;

	basedev = block->base;
	private = (struct dasd_eckd_private *) basedev->private;

	/* Calculate number of blocks/records per track. */
	blksize = block->bp_block;
	blk_per_trk = recs_per_track(&private->rdc_data, 0, blksize);
	if (blk_per_trk == 0)
		return ERR_PTR(-EINVAL);
	/* Calculate record id of first and last block. */
	first_rec = first_trk = blk_rq_pos(req) >> block->s2b_shift;
	first_offs = sector_div(first_trk, blk_per_trk);
	last_rec = last_trk =
		(blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
	last_offs = sector_div(last_trk, blk_per_trk);
	cdlspecial = (private->uses_cdl && first_rec < 2*blk_per_trk);

	fcx_multitrack = private->features.feature[40] & 0x20;
	data_size = blk_rq_bytes(req);
	/* tpm write request add CBC data on each track boundary */
	if (rq_data_dir(req) == WRITE)
		data_size += (last_trk - first_trk) * 4;

	/* is read track data and write track data in command mode supported? */
	cmdrtd = private->features.feature[9] & 0x20;
	cmdwtd = private->features.feature[12] & 0x40;
	use_prefix = private->features.feature[8] & 0x01;

	cqr = NULL;
	if (cdlspecial || dasd_page_cache) {
		/* do nothing, just fall through to the cmd mode single case */
	} else if ((data_size <= private->fcx_max_data)
		   && (fcx_multitrack || (first_trk == last_trk))) {
		cqr = dasd_eckd_build_cp_tpm_track(startdev, block, req,
						    first_rec, last_rec,
						    first_trk, last_trk,
						    first_offs, last_offs,
						    blk_per_trk, blksize);
		if (IS_ERR(cqr) && (PTR_ERR(cqr) != -EAGAIN) &&
		    (PTR_ERR(cqr) != -ENOMEM))
			cqr = NULL;
	} else if (use_prefix &&
		   (((rq_data_dir(req) == READ) && cmdrtd) ||
		    ((rq_data_dir(req) == WRITE) && cmdwtd))) {
		cqr = dasd_eckd_build_cp_cmd_track(startdev, block, req,
						   first_rec, last_rec,
						   first_trk, last_trk,
						   first_offs, last_offs,
						   blk_per_trk, blksize);
		if (IS_ERR(cqr) && (PTR_ERR(cqr) != -EAGAIN) &&
		    (PTR_ERR(cqr) != -ENOMEM))
			cqr = NULL;
	}
	if (!cqr)
		cqr = dasd_eckd_build_cp_cmd_single(startdev, block, req,
						    first_rec, last_rec,
						    first_trk, last_trk,
						    first_offs, last_offs,
						    blk_per_trk, blksize);
	return cqr;
}

static struct dasd_ccw_req *dasd_raw_build_cp(struct dasd_device *startdev,
					       struct dasd_block *block,
					       struct request *req)
{
	unsigned long *idaws;
	struct dasd_device *basedev;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	struct req_iterator iter;
	struct bio_vec *bv;
	char *dst;
	unsigned char cmd;
	unsigned int trkcount;
	unsigned int seg_len, len_to_track_end;
	unsigned int first_offs;
	unsigned int cidaw, cplength, datasize;
	sector_t first_trk, last_trk;
	unsigned int pfx_datasize;

	/*
	 * raw track access needs to be mutiple of 64k and on 64k boundary
	 */
	if ((blk_rq_pos(req) % DASD_RAW_SECTORS_PER_TRACK) != 0) {
		cqr = ERR_PTR(-EINVAL);
		goto out;
	}
	if (((blk_rq_pos(req) + blk_rq_sectors(req)) %
	     DASD_RAW_SECTORS_PER_TRACK) != 0) {
		cqr = ERR_PTR(-EINVAL);
		goto out;
	}

	first_trk = blk_rq_pos(req) / DASD_RAW_SECTORS_PER_TRACK;
	last_trk = (blk_rq_pos(req) + blk_rq_sectors(req) - 1) /
		DASD_RAW_SECTORS_PER_TRACK;
	trkcount = last_trk - first_trk + 1;
	first_offs = 0;
	basedev = block->base;

	if (rq_data_dir(req) == READ)
		cmd = DASD_ECKD_CCW_READ_TRACK;
	else if (rq_data_dir(req) == WRITE)
		cmd = DASD_ECKD_CCW_WRITE_FULL_TRACK;
	else {
		cqr = ERR_PTR(-EINVAL);
		goto out;
	}

	/*
	 * Raw track based I/O needs IDAWs for each page,
	 * and not just for 64 bit addresses.
	 */
	cidaw = trkcount * DASD_RAW_BLOCK_PER_TRACK;

	/* 1x prefix + one read/write ccw per track */
	cplength = 1 + trkcount;

	/*
	 * struct PFX_eckd_data has up to 2 byte as extended parameter
	 * this is needed for write full track and has to be mentioned
	 * separately
	 * add 8 instead of 2 to keep 8 byte boundary
	 */
	pfx_datasize = sizeof(struct PFX_eckd_data) + 8;

	datasize = pfx_datasize + cidaw * sizeof(unsigned long long);

	/* Allocate the ccw request. */
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength,
				   datasize, startdev);
	if (IS_ERR(cqr))
		goto out;
	ccw = cqr->cpaddr;

	if (prefix_LRE(ccw++, cqr->data, first_trk, last_trk, cmd,
		       basedev, startdev, 1 /* format */, first_offs + 1,
		       trkcount, 0, 0) == -EAGAIN) {
		/* Clock not in sync and XRC is enabled.
		 * Try again later.
		 */
		dasd_sfree_request(cqr, startdev);
		cqr = ERR_PTR(-EAGAIN);
		goto out;
	}

	idaws = (unsigned long *)(cqr->data + pfx_datasize);

	len_to_track_end = 0;

	rq_for_each_segment(bv, req, iter) {
		dst = page_address(bv->bv_page) + bv->bv_offset;
		seg_len = bv->bv_len;
		if (!len_to_track_end) {
			ccw[-1].flags |= CCW_FLAG_CC;
			ccw->cmd_code = cmd;
			/* maximum 3390 track size */
			ccw->count = 57326;
			/* 64k map to one track */
			len_to_track_end = 65536;
			ccw->cda = (__u32)(addr_t)idaws;
			ccw->flags |= CCW_FLAG_IDA;
			ccw->flags |= CCW_FLAG_SLI;
			ccw++;
		}
		len_to_track_end -= seg_len;
		idaws = idal_create_words(idaws, dst, seg_len);
	}

	if (blk_noretry_request(req) ||
	    block->base->features & DASD_FEATURE_FAILFAST)
		set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->startdev = startdev;
	cqr->memdev = startdev;
	cqr->block = block;
	cqr->expires = startdev->default_expires * HZ;
	cqr->lpm = startdev->path_data.ppm;
	cqr->retries = 256;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;

	if (IS_ERR(cqr) && PTR_ERR(cqr) != -EAGAIN)
		cqr = NULL;
out:
	return cqr;
}


static int
dasd_eckd_free_cp(struct dasd_ccw_req *cqr, struct request *req)
{
	struct dasd_eckd_private *private;
	struct ccw1 *ccw;
	struct req_iterator iter;
	struct bio_vec *bv;
	char *dst, *cda;
	unsigned int blksize, blk_per_trk, off;
	sector_t recid;
	int status;

	if (!dasd_page_cache)
		goto out;
	private = (struct dasd_eckd_private *) cqr->block->base->private;
	blksize = cqr->block->bp_block;
	blk_per_trk = recs_per_track(&private->rdc_data, 0, blksize);
	recid = blk_rq_pos(req) >> cqr->block->s2b_shift;
	ccw = cqr->cpaddr;
	/* Skip over define extent & locate record. */
	ccw++;
	if (private->uses_cdl == 0 || recid > 2*blk_per_trk)
		ccw++;
	rq_for_each_segment(bv, req, iter) {
		dst = page_address(bv->bv_page) + bv->bv_offset;
		for (off = 0; off < bv->bv_len; off += blksize) {
			/* Skip locate record. */
			if (private->uses_cdl && recid <= 2*blk_per_trk)
				ccw++;
			if (dst) {
				if (ccw->flags & CCW_FLAG_IDA)
					cda = *((char **)((addr_t) ccw->cda));
				else
					cda = (char *)((addr_t) ccw->cda);
				if (dst != cda) {
					if (rq_data_dir(req) == READ)
						memcpy(dst, cda, bv->bv_len);
					kmem_cache_free(dasd_page_cache,
					    (void *)((addr_t)cda & PAGE_MASK));
				}
				dst = NULL;
			}
			ccw++;
			recid++;
		}
	}
out:
	status = cqr->status == DASD_CQR_DONE;
	dasd_sfree_request(cqr, cqr->memdev);
	return status;
}

/*
 * Modify ccw/tcw in cqr so it can be started on a base device.
 *
 * Note that this is not enough to restart the cqr!
 * Either reset cqr->startdev as well (summary unit check handling)
 * or restart via separate cqr (as in ERP handling).
 */
void dasd_eckd_reset_ccw_to_base_io(struct dasd_ccw_req *cqr)
{
	struct ccw1 *ccw;
	struct PFX_eckd_data *pfxdata;
	struct tcw *tcw;
	struct tccb *tccb;
	struct dcw *dcw;

	if (cqr->cpmode == 1) {
		tcw = cqr->cpaddr;
		tccb = tcw_get_tccb(tcw);
		dcw = (struct dcw *)&tccb->tca[0];
		pfxdata = (struct PFX_eckd_data *)&dcw->cd[0];
		pfxdata->validity.verify_base = 0;
		pfxdata->validity.hyper_pav = 0;
	} else {
		ccw = cqr->cpaddr;
		pfxdata = cqr->data;
		if (ccw->cmd_code == DASD_ECKD_CCW_PFX) {
			pfxdata->validity.verify_base = 0;
			pfxdata->validity.hyper_pav = 0;
		}
	}
}

#define DASD_ECKD_CHANQ_MAX_SIZE 4

static struct dasd_ccw_req *dasd_eckd_build_alias_cp(struct dasd_device *base,
						     struct dasd_block *block,
						     struct request *req)
{
	struct dasd_eckd_private *private;
	struct dasd_device *startdev;
	unsigned long flags;
	struct dasd_ccw_req *cqr;

	startdev = dasd_alias_get_start_dev(base);
	if (!startdev)
		startdev = base;
	private = (struct dasd_eckd_private *) startdev->private;
	if (private->count >= DASD_ECKD_CHANQ_MAX_SIZE)
		return ERR_PTR(-EBUSY);

	spin_lock_irqsave(get_ccwdev_lock(startdev->cdev), flags);
	private->count++;
	if ((base->features & DASD_FEATURE_USERAW))
		cqr = dasd_raw_build_cp(startdev, block, req);
	else
		cqr = dasd_eckd_build_cp(startdev, block, req);
	if (IS_ERR(cqr))
		private->count--;
	spin_unlock_irqrestore(get_ccwdev_lock(startdev->cdev), flags);
	return cqr;
}

static int dasd_eckd_free_alias_cp(struct dasd_ccw_req *cqr,
				   struct request *req)
{
	struct dasd_eckd_private *private;
	unsigned long flags;

	spin_lock_irqsave(get_ccwdev_lock(cqr->memdev->cdev), flags);
	private = (struct dasd_eckd_private *) cqr->memdev->private;
	private->count--;
	spin_unlock_irqrestore(get_ccwdev_lock(cqr->memdev->cdev), flags);
	return dasd_eckd_free_cp(cqr, req);
}

static int
dasd_eckd_fill_info(struct dasd_device * device,
		    struct dasd_information2_t * info)
{
	struct dasd_eckd_private *private;

	private = (struct dasd_eckd_private *) device->private;
	info->label_block = 2;
	info->FBA_layout = private->uses_cdl ? 0 : 1;
	info->format = private->uses_cdl ? DASD_FORMAT_CDL : DASD_FORMAT_LDL;
	info->characteristics_size = sizeof(struct dasd_eckd_characteristics);
	memcpy(info->characteristics, &private->rdc_data,
	       sizeof(struct dasd_eckd_characteristics));
	info->confdata_size = min((unsigned long)private->conf_len,
				  sizeof(info->configuration_data));
	memcpy(info->configuration_data, private->conf_data,
	       info->confdata_size);
	return 0;
}

/*
 * SECTION: ioctl functions for eckd devices.
 */

/*
 * Release device ioctl.
 * Buils a channel programm to releases a prior reserved
 * (see dasd_eckd_reserve) device.
 */
static int
dasd_eckd_release(struct dasd_device *device)
{
	struct dasd_ccw_req *cqr;
	int rc;
	struct ccw1 *ccw;
	int useglobal;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	useglobal = 0;
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
	if (IS_ERR(cqr)) {
		mutex_lock(&dasd_reserve_mutex);
		useglobal = 1;
		cqr = &dasd_reserve_req->cqr;
		memset(cqr, 0, sizeof(*cqr));
		memset(&dasd_reserve_req->ccw, 0,
		       sizeof(dasd_reserve_req->ccw));
		cqr->cpaddr = &dasd_reserve_req->ccw;
		cqr->data = &dasd_reserve_req->data;
		cqr->magic = DASD_ECKD_MAGIC;
	}
	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_RELEASE;
	ccw->flags |= CCW_FLAG_SLI;
	ccw->count = 32;
	ccw->cda = (__u32)(addr_t) cqr->data;
	cqr->startdev = device;
	cqr->memdev = device;
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->retries = 2;	/* set retry counter to enable basic ERP */
	cqr->expires = 2 * HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;

	rc = dasd_sleep_on_immediatly(cqr);
	if (!rc)
		clear_bit(DASD_FLAG_IS_RESERVED, &device->flags);

	if (useglobal)
		mutex_unlock(&dasd_reserve_mutex);
	else
		dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * Reserve device ioctl.
 * Options are set to 'synchronous wait for interrupt' and
 * 'timeout the request'. This leads to a terminate IO if
 * the interrupt is outstanding for a certain time.
 */
static int
dasd_eckd_reserve(struct dasd_device *device)
{
	struct dasd_ccw_req *cqr;
	int rc;
	struct ccw1 *ccw;
	int useglobal;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	useglobal = 0;
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
	if (IS_ERR(cqr)) {
		mutex_lock(&dasd_reserve_mutex);
		useglobal = 1;
		cqr = &dasd_reserve_req->cqr;
		memset(cqr, 0, sizeof(*cqr));
		memset(&dasd_reserve_req->ccw, 0,
		       sizeof(dasd_reserve_req->ccw));
		cqr->cpaddr = &dasd_reserve_req->ccw;
		cqr->data = &dasd_reserve_req->data;
		cqr->magic = DASD_ECKD_MAGIC;
	}
	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_RESERVE;
	ccw->flags |= CCW_FLAG_SLI;
	ccw->count = 32;
	ccw->cda = (__u32)(addr_t) cqr->data;
	cqr->startdev = device;
	cqr->memdev = device;
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->retries = 2;	/* set retry counter to enable basic ERP */
	cqr->expires = 2 * HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;

	rc = dasd_sleep_on_immediatly(cqr);
	if (!rc)
		set_bit(DASD_FLAG_IS_RESERVED, &device->flags);

	if (useglobal)
		mutex_unlock(&dasd_reserve_mutex);
	else
		dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * Steal lock ioctl - unconditional reserve device.
 * Buils a channel programm to break a device's reservation.
 * (unconditional reserve)
 */
static int
dasd_eckd_steal_lock(struct dasd_device *device)
{
	struct dasd_ccw_req *cqr;
	int rc;
	struct ccw1 *ccw;
	int useglobal;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	useglobal = 0;
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device);
	if (IS_ERR(cqr)) {
		mutex_lock(&dasd_reserve_mutex);
		useglobal = 1;
		cqr = &dasd_reserve_req->cqr;
		memset(cqr, 0, sizeof(*cqr));
		memset(&dasd_reserve_req->ccw, 0,
		       sizeof(dasd_reserve_req->ccw));
		cqr->cpaddr = &dasd_reserve_req->ccw;
		cqr->data = &dasd_reserve_req->data;
		cqr->magic = DASD_ECKD_MAGIC;
	}
	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_SLCK;
	ccw->flags |= CCW_FLAG_SLI;
	ccw->count = 32;
	ccw->cda = (__u32)(addr_t) cqr->data;
	cqr->startdev = device;
	cqr->memdev = device;
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	cqr->retries = 2;	/* set retry counter to enable basic ERP */
	cqr->expires = 2 * HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;

	rc = dasd_sleep_on_immediatly(cqr);
	if (!rc)
		set_bit(DASD_FLAG_IS_RESERVED, &device->flags);

	if (useglobal)
		mutex_unlock(&dasd_reserve_mutex);
	else
		dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * SNID - Sense Path Group ID
 * This ioctl may be used in situations where I/O is stalled due to
 * a reserve, so if the normal dasd_smalloc_request fails, we use the
 * preallocated dasd_reserve_req.
 */
static int dasd_eckd_snid(struct dasd_device *device,
			  void __user *argp)
{
	struct dasd_ccw_req *cqr;
	int rc;
	struct ccw1 *ccw;
	int useglobal;
	struct dasd_snid_ioctl_data usrparm;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
		return -EFAULT;

	useglobal = 0;
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1,
				   sizeof(struct dasd_snid_data), device);
	if (IS_ERR(cqr)) {
		mutex_lock(&dasd_reserve_mutex);
		useglobal = 1;
		cqr = &dasd_reserve_req->cqr;
		memset(cqr, 0, sizeof(*cqr));
		memset(&dasd_reserve_req->ccw, 0,
		       sizeof(dasd_reserve_req->ccw));
		cqr->cpaddr = &dasd_reserve_req->ccw;
		cqr->data = &dasd_reserve_req->data;
		cqr->magic = DASD_ECKD_MAGIC;
	}
	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_SNID;
	ccw->flags |= CCW_FLAG_SLI;
	ccw->count = 12;
	ccw->cda = (__u32)(addr_t) cqr->data;
	cqr->startdev = device;
	cqr->memdev = device;
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
	set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags);
	cqr->retries = 5;
	cqr->expires = 10 * HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	cqr->lpm = usrparm.path_mask;

	rc = dasd_sleep_on_immediatly(cqr);
	/* verify that I/O processing didn't modify the path mask */
	if (!rc && usrparm.path_mask && (cqr->lpm != usrparm.path_mask))
		rc = -EIO;
	if (!rc) {
		usrparm.data = *((struct dasd_snid_data *)cqr->data);
		if (copy_to_user(argp, &usrparm, sizeof(usrparm)))
			rc = -EFAULT;
	}

	if (useglobal)
		mutex_unlock(&dasd_reserve_mutex);
	else
		dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * Read performance statistics
 */
static int
dasd_eckd_performance(struct dasd_device *device, void __user *argp)
{
	struct dasd_psf_prssd_data *prssdp;
	struct dasd_rssd_perf_stats_t *stats;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	int rc;

	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */  + 1 /* RSSD */,
				   (sizeof(struct dasd_psf_prssd_data) +
				    sizeof(struct dasd_rssd_perf_stats_t)),
				   device);
	if (IS_ERR(cqr)) {
		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
			    "Could not allocate initialization request");
		return PTR_ERR(cqr);
	}
	cqr->startdev = device;
	cqr->memdev = device;
	cqr->retries = 0;
	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
	cqr->expires = 10 * HZ;

	/* Prepare for Read Subsystem Data */
	prssdp = (struct dasd_psf_prssd_data *) cqr->data;
	memset(prssdp, 0, sizeof(struct dasd_psf_prssd_data));
	prssdp->order = PSF_ORDER_PRSSD;
	prssdp->suborder = 0x01;	/* Performance Statistics */
	prssdp->varies[1] = 0x01;	/* Perf Statistics for the Subsystem */

	ccw = cqr->cpaddr;
	ccw->cmd_code = DASD_ECKD_CCW_PSF;
	ccw->count = sizeof(struct dasd_psf_prssd_data);
	ccw->flags |= CCW_FLAG_CC;
	ccw->cda = (__u32)(addr_t) prssdp;

	/* Read Subsystem Data - Performance Statistics */
	stats = (struct dasd_rssd_perf_stats_t *) (prssdp + 1);
	memset(stats, 0, sizeof(struct dasd_rssd_perf_stats_t));

	ccw++;
	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
	ccw->count = sizeof(struct dasd_rssd_perf_stats_t);
	ccw->cda = (__u32)(addr_t) stats;

	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;
	rc = dasd_sleep_on(cqr);
	if (rc == 0) {
		prssdp = (struct dasd_psf_prssd_data *) cqr->data;
		stats = (struct dasd_rssd_perf_stats_t *) (prssdp + 1);
		if (copy_to_user(argp, stats,
				 sizeof(struct dasd_rssd_perf_stats_t)))
			rc = -EFAULT;
	}
	dasd_sfree_request(cqr, cqr->memdev);
	return rc;
}

/*
 * Get attributes (cache operations)
 * Returnes the cache attributes used in Define Extend (DE).
 */
static int
dasd_eckd_get_attrib(struct dasd_device *device, void __user *argp)
{
	struct dasd_eckd_private *private =
		(struct dasd_eckd_private *)device->private;
	struct attrib_data_t attrib = private->attrib;
	int rc;

        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
	if (!argp)
                return -EINVAL;

	rc = 0;
	if (copy_to_user(argp, (long *) &attrib,
			 sizeof(struct attrib_data_t)))
		rc = -EFAULT;

	return rc;
}

/*
 * Set attributes (cache operations)
 * Stores the attributes for cache operation to be used in Define Extend (DE).
 */
static int
dasd_eckd_set_attrib(struct dasd_device *device, void __user *argp)
{
	struct dasd_eckd_private *private =
		(struct dasd_eckd_private *)device->private;
	struct attrib_data_t attrib;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if (!argp)
		return -EINVAL;

	if (copy_from_user(&attrib, argp, sizeof(struct attrib_data_t)))
		return -EFAULT;
	private->attrib = attrib;

	dev_info(&device->cdev->dev,
		 "The DASD cache mode was set to %x (%i cylinder prestage)\n",
		 private->attrib.operation, private->attrib.nr_cyl);
	return 0;
}

/*
 * Issue syscall I/O to EMC Symmetrix array.
 * CCWs are PSF and RSSD
 */
static int dasd_symm_io(struct dasd_device *device, void __user *argp)
{
	struct dasd_symmio_parms usrparm;
	char *psf_data, *rssd_result;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	char psf0, psf1;
	int rc;

	if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RAWIO))
		return -EACCES;
	psf0 = psf1 = 0;

	/* Copy parms from caller */
	rc = -EFAULT;
	if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
		goto out;
	if (is_compat_task() || sizeof(long) == 4) {
		/* Make sure pointers are sane even on 31 bit. */
		rc = -EINVAL;
		if ((usrparm.psf_data >> 32) != 0)
			goto out;
		if ((usrparm.rssd_result >> 32) != 0)
			goto out;
		usrparm.psf_data &= 0x7fffffffULL;
		usrparm.rssd_result &= 0x7fffffffULL;
	}
	/* alloc I/O data area */
	psf_data = kzalloc(usrparm.psf_data_len, GFP_KERNEL | GFP_DMA);
	rssd_result = kzalloc(usrparm.rssd_result_len, GFP_KERNEL | GFP_DMA);
	if (!psf_data || !rssd_result) {
		rc = -ENOMEM;
		goto out_free;
	}

	/* get syscall header from user space */
	rc = -EFAULT;
	if (copy_from_user(psf_data,
			   (void __user *)(unsigned long) usrparm.psf_data,
			   usrparm.psf_data_len))
		goto out_free;
	psf0 = psf_data[0];
	psf1 = psf_data[1];

	/* setup CCWs for PSF + RSSD */
	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 2 , 0, device);
	if (IS_ERR(cqr)) {
		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
			"Could not allocate initialization request");
		rc = PTR_ERR(cqr);
		goto out_free;
	}

	cqr->startdev = device;
	cqr->memdev = device;
	cqr->retries = 3;
	cqr->expires = 10 * HZ;
	cqr->buildclk = get_clock();
	cqr->status = DASD_CQR_FILLED;

	/* Build the ccws */
	ccw = cqr->cpaddr;

	/* PSF ccw */
	ccw->cmd_code = DASD_ECKD_CCW_PSF;
	ccw->count = usrparm.psf_data_len;
	ccw->flags |= CCW_FLAG_CC;
	ccw->cda = (__u32)(addr_t) psf_data;

	ccw++;

	/* RSSD ccw  */
	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
	ccw->count = usrparm.rssd_result_len;
	ccw->flags = CCW_FLAG_SLI ;
	ccw->cda = (__u32)(addr_t) rssd_result;

	rc = dasd_sleep_on(cqr);
	if (rc)
		goto out_sfree;

	rc = -EFAULT;
	if (copy_to_user((void __user *)(unsigned long) usrparm.rssd_result,
			   rssd_result, usrparm.rssd_result_len))
		goto out_sfree;
	rc = 0;

out_sfree:
	dasd_sfree_request(cqr, cqr->memdev);
out_free:
	kfree(rssd_result);
	kfree(psf_data);
out:
	DBF_DEV_EVENT(DBF_WARNING, device,
		      "Symmetrix ioctl (0x%02x 0x%02x): rc=%d",
		      (int) psf0, (int) psf1, rc);
	return rc;
}

static int
dasd_eckd_ioctl(struct dasd_block *block, unsigned int cmd, void __user *argp)
{
	struct dasd_device *device = block->base;

	switch (cmd) {
	case BIODASDGATTR:
		return dasd_eckd_get_attrib(device, argp);
	case BIODASDSATTR:
		return dasd_eckd_set_attrib(device, argp);
	case BIODASDPSRD:
		return dasd_eckd_performance(device, argp);
	case BIODASDRLSE:
		return dasd_eckd_release(device);
	case BIODASDRSRV:
		return dasd_eckd_reserve(device);
	case BIODASDSLCK:
		return dasd_eckd_steal_lock(device);
	case BIODASDSNID:
		return dasd_eckd_snid(device, argp);
	case BIODASDSYMMIO:
		return dasd_symm_io(device, argp);
	default:
		return -ENOTTY;
	}
}

/*
 * Dump the range of CCWs into 'page' buffer
 * and return number of printed chars.
 */
static int
dasd_eckd_dump_ccw_range(struct ccw1 *from, struct ccw1 *to, char *page)
{
	int len, count;
	char *datap;

	len = 0;
	while (from <= to) {
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " CCW %p: %08X %08X DAT:",
			       from, ((int *) from)[0], ((int *) from)[1]);

		/* get pointer to data (consider IDALs) */
		if (from->flags & CCW_FLAG_IDA)
			datap = (char *) *((addr_t *) (addr_t) from->cda);
		else
			datap = (char *) ((addr_t) from->cda);

		/* dump data (max 32 bytes) */
		for (count = 0; count < from->count && count < 32; count++) {
			if (count % 8 == 0) len += sprintf(page + len, " ");
			if (count % 4 == 0) len += sprintf(page + len, " ");
			len += sprintf(page + len, "%02x", datap[count]);
		}
		len += sprintf(page + len, "\n");
		from++;
	}
	return len;
}

static void
dasd_eckd_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
			 char *reason)
{
	u64 *sense;
	u64 *stat;

	sense = (u64 *) dasd_get_sense(irb);
	stat = (u64 *) &irb->scsw;
	if (sense) {
		DBF_DEV_EVENT(DBF_EMERG, device, "%s: %016llx %08x : "
			      "%016llx %016llx %016llx %016llx",
			      reason, *stat, *((u32 *) (stat + 1)),
			      sense[0], sense[1], sense[2], sense[3]);
	} else {
		DBF_DEV_EVENT(DBF_EMERG, device, "%s: %016llx %08x : %s",
			      reason, *stat, *((u32 *) (stat + 1)),
			      "NO VALID SENSE");
	}
}

/*
 * Print sense data and related channel program.
 * Parts are printed because printk buffer is only 1024 bytes.
 */
static void dasd_eckd_dump_sense_ccw(struct dasd_device *device,
				 struct dasd_ccw_req *req, struct irb *irb)
{
	char *page;
	struct ccw1 *first, *last, *fail, *from, *to;
	int len, sl, sct;

	page = (char *) get_zeroed_page(GFP_ATOMIC);
	if (page == NULL) {
		DBF_DEV_EVENT(DBF_WARNING, device, "%s",
			      "No memory to dump sense data\n");
		return;
	}
	/* dump the sense data */
	len = sprintf(page,  KERN_ERR PRINTK_HEADER
		      " I/O status report for device %s:\n",
		      dev_name(&device->cdev->dev));
	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
		       " in req: %p CC:%02X FC:%02X AC:%02X SC:%02X DS:%02X "
		       "CS:%02X RC:%d\n",
		       req, scsw_cc(&irb->scsw), scsw_fctl(&irb->scsw),
		       scsw_actl(&irb->scsw), scsw_stctl(&irb->scsw),
		       scsw_dstat(&irb->scsw), scsw_cstat(&irb->scsw),
		       req ? req->intrc : 0);
	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
		       " device %s: Failing CCW: %p\n",
		       dev_name(&device->cdev->dev),
		       (void *) (addr_t) irb->scsw.cmd.cpa);
	if (irb->esw.esw0.erw.cons) {
		for (sl = 0; sl < 4; sl++) {
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
				       " Sense(hex) %2d-%2d:",
				       (8 * sl), ((8 * sl) + 7));

			for (sct = 0; sct < 8; sct++) {
				len += sprintf(page + len, " %02x",
					       irb->ecw[8 * sl + sct]);
			}
			len += sprintf(page + len, "\n");
		}

		if (irb->ecw[27] & DASD_SENSE_BIT_0) {
			/* 24 Byte Sense Data */
			sprintf(page + len, KERN_ERR PRINTK_HEADER
				" 24 Byte: %x MSG %x, "
				"%s MSGb to SYSOP\n",
				irb->ecw[7] >> 4, irb->ecw[7] & 0x0f,
				irb->ecw[1] & 0x10 ? "" : "no");
		} else {
			/* 32 Byte Sense Data */
			sprintf(page + len, KERN_ERR PRINTK_HEADER
				" 32 Byte: Format: %x "
				"Exception class %x\n",
				irb->ecw[6] & 0x0f, irb->ecw[22] >> 4);
		}
	} else {
		sprintf(page + len, KERN_ERR PRINTK_HEADER
			" SORRY - NO VALID SENSE AVAILABLE\n");
	}
	printk("%s", page);

	if (req) {
		/* req == NULL for unsolicited interrupts */
		/* dump the Channel Program (max 140 Bytes per line) */
		/* Count CCW and print first CCWs (maximum 1024 % 140 = 7) */
		first = req->cpaddr;
		for (last = first; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
		to = min(first + 6, last);
		len = sprintf(page,  KERN_ERR PRINTK_HEADER
			      " Related CP in req: %p\n", req);
		dasd_eckd_dump_ccw_range(first, to, page + len);
		printk("%s", page);

		/* print failing CCW area (maximum 4) */
		/* scsw->cda is either valid or zero  */
		len = 0;
		from = ++to;
		fail = (struct ccw1 *)(addr_t)
				irb->scsw.cmd.cpa; /* failing CCW */
		if (from <  fail - 2) {
			from = fail - 2;     /* there is a gap - print header */
			len += sprintf(page, KERN_ERR PRINTK_HEADER "......\n");
		}
		to = min(fail + 1, last);
		len += dasd_eckd_dump_ccw_range(from, to, page + len);

		/* print last CCWs (maximum 2) */
		from = max(from, ++to);
		if (from < last - 1) {
			from = last - 1;     /* there is a gap - print header */
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
		}
		len += dasd_eckd_dump_ccw_range(from, last, page + len);
		if (len > 0)
			printk("%s", page);
	}
	free_page((unsigned long) page);
}


/*
 * Print sense data from a tcw.
 */
static void dasd_eckd_dump_sense_tcw(struct dasd_device *device,
				 struct dasd_ccw_req *req, struct irb *irb)
{
	char *page;
	int len, sl, sct, residual;
	struct tsb *tsb;
	u8 *sense, *rcq;

	page = (char *) get_zeroed_page(GFP_ATOMIC);
	if (page == NULL) {
		DBF_DEV_EVENT(DBF_WARNING, device, " %s",
			    "No memory to dump sense data");
		return;
	}
	/* dump the sense data */
	len = sprintf(page,  KERN_ERR PRINTK_HEADER
		      " I/O status report for device %s:\n",
		      dev_name(&device->cdev->dev));
	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
		       " in req: %p CC:%02X FC:%02X AC:%02X SC:%02X DS:%02X "
		       "CS:%02X fcxs:%02X schxs:%02X RC:%d\n",
		       req, scsw_cc(&irb->scsw), scsw_fctl(&irb->scsw),
		       scsw_actl(&irb->scsw), scsw_stctl(&irb->scsw),
		       scsw_dstat(&irb->scsw), scsw_cstat(&irb->scsw),
		       irb->scsw.tm.fcxs, irb->scsw.tm.schxs,
		       req ? req->intrc : 0);
	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
		       " device %s: Failing TCW: %p\n",
		       dev_name(&device->cdev->dev),
		       (void *) (addr_t) irb->scsw.tm.tcw);

	tsb = NULL;
	sense = NULL;
	if (irb->scsw.tm.tcw && (irb->scsw.tm.fcxs & 0x01))
		tsb = tcw_get_tsb(
			(struct tcw *)(unsigned long)irb->scsw.tm.tcw);

	if (tsb) {
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->length %d\n", tsb->length);
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->flags %x\n", tsb->flags);
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->dcw_offset %d\n", tsb->dcw_offset);
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->count %d\n", tsb->count);
		residual = tsb->count - 28;
		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " residual %d\n", residual);

		switch (tsb->flags & 0x07) {
		case 1:	/* tsa_iostat */
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.iostat.dev_time %d\n",
				       tsb->tsa.iostat.dev_time);
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.iostat.def_time %d\n",
				       tsb->tsa.iostat.def_time);
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.iostat.queue_time %d\n",
				       tsb->tsa.iostat.queue_time);
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.iostat.dev_busy_time %d\n",
				       tsb->tsa.iostat.dev_busy_time);
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.iostat.dev_act_time %d\n",
				       tsb->tsa.iostat.dev_act_time);
			sense = tsb->tsa.iostat.sense;
			break;
		case 2: /* ts_ddpc */
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
			       " tsb->tsa.ddpc.rc %d\n", tsb->tsa.ddpc.rc);
			for (sl = 0; sl < 2; sl++) {
				len += sprintf(page + len,
					       KERN_ERR PRINTK_HEADER
					       " tsb->tsa.ddpc.rcq %2d-%2d: ",
					       (8 * sl), ((8 * sl) + 7));
				rcq = tsb->tsa.ddpc.rcq;
				for (sct = 0; sct < 8; sct++) {
					len += sprintf(page + len, " %02x",
						       rcq[8 * sl + sct]);
				}
				len += sprintf(page + len, "\n");
			}
			sense = tsb->tsa.ddpc.sense;
			break;
		case 3: /* tsa_intrg */
			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
				      " tsb->tsa.intrg.: not supportet yet \n");
			break;
		}

		if (sense) {
			for (sl = 0; sl < 4; sl++) {
				len += sprintf(page + len,
					       KERN_ERR PRINTK_HEADER
					       " Sense(hex) %2d-%2d:",
					       (8 * sl), ((8 * sl) + 7));
				for (sct = 0; sct < 8; sct++) {
					len += sprintf(page + len, " %02x",
						       sense[8 * sl + sct]);
				}
				len += sprintf(page + len, "\n");
			}

			if (sense[27] & DASD_SENSE_BIT_0) {
				/* 24 Byte Sense Data */
				sprintf(page + len, KERN_ERR PRINTK_HEADER
					" 24 Byte: %x MSG %x, "
					"%s MSGb to SYSOP\n",
					sense[7] >> 4, sense[7] & 0x0f,
					sense[1] & 0x10 ? "" : "no");
			} else {
				/* 32 Byte Sense Data */
				sprintf(page + len, KERN_ERR PRINTK_HEADER
					" 32 Byte: Format: %x "
					"Exception class %x\n",
					sense[6] & 0x0f, sense[22] >> 4);
			}
		} else {
			sprintf(page + len, KERN_ERR PRINTK_HEADER
				" SORRY - NO VALID SENSE AVAILABLE\n");
		}
	} else {
		sprintf(page + len, KERN_ERR PRINTK_HEADER
			" SORRY - NO TSB DATA AVAILABLE\n");
	}
	printk("%s", page);
	free_page((unsigned long) page);
}

static void dasd_eckd_dump_sense(struct dasd_device *device,
				 struct dasd_ccw_req *req, struct irb *irb)
{
	if (scsw_is_tm(&irb->scsw))
		dasd_eckd_dump_sense_tcw(device, req, irb);
	else
		dasd_eckd_dump_sense_ccw(device, req, irb);
}

static int dasd_eckd_pm_freeze(struct dasd_device *device)
{
	/*
	 * the device should be disconnected from our LCU structure
	 * on restore we will reconnect it and reread LCU specific
	 * information like PAV support that might have changed
	 */
	dasd_alias_remove_device(device);
	dasd_alias_disconnect_device_from_lcu(device);

	return 0;
}

static int dasd_eckd_restore_device(struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	struct dasd_eckd_characteristics temp_rdc_data;
	int rc;
	struct dasd_uid temp_uid;
	unsigned long flags;

	private = (struct dasd_eckd_private *) device->private;

	/* Read Configuration Data */
	rc = dasd_eckd_read_conf(device);
	if (rc)
		goto out_err;

	dasd_eckd_get_uid(device, &temp_uid);
	/* Generate device unique id */
	rc = dasd_eckd_generate_uid(device);
	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
	if (memcmp(&private->uid, &temp_uid, sizeof(struct dasd_uid)) != 0)
		dev_err(&device->cdev->dev, "The UID of the DASD has "
			"changed\n");
	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
	if (rc)
		goto out_err;

	/* register lcu with alias handling, enable PAV if this is a new lcu */
	rc = dasd_alias_make_device_known_to_lcu(device);
	if (rc)
		return rc;
	dasd_eckd_validate_server(device, DASD_CQR_FLAGS_FAILFAST);

	/* RE-Read Configuration Data */
	rc = dasd_eckd_read_conf(device);
	if (rc)
		goto out_err;

	/* Read Feature Codes */
	dasd_eckd_read_features(device);

	/* Read Device Characteristics */
	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
					 &temp_rdc_data, 64);
	if (rc) {
		DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
				"Read device characteristic failed, rc=%d", rc);
		goto out_err;
	}
	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
	memcpy(&private->rdc_data, &temp_rdc_data, sizeof(temp_rdc_data));
	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);

	/* add device to alias management */
	dasd_alias_add_device(device);

	return 0;

out_err:
	return -1;
}

static int dasd_eckd_reload_device(struct dasd_device *device)
{
	struct dasd_eckd_private *private;
	int rc, old_base;
	char print_uid[60];
	struct dasd_uid uid;
	unsigned long flags;

	private = (struct dasd_eckd_private *) device->private;

	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
	old_base = private->uid.base_unit_addr;
	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);

	/* Read Configuration Data */
	rc = dasd_eckd_read_conf(device);
	if (rc)
		goto out_err;

	rc = dasd_eckd_generate_uid(device);
	if (rc)
		goto out_err;
	/*
	 * update unit address configuration and
	 * add device to alias management
	 */
	dasd_alias_update_add_device(device);

	dasd_eckd_get_uid(device, &uid);

	if (old_base != uid.base_unit_addr) {
		if (strlen(uid.vduit) > 0)
			snprintf(print_uid, sizeof(print_uid),
				 "%s.%s.%04x.%02x.%s", uid.vendor, uid.serial,
				 uid.ssid, uid.base_unit_addr, uid.vduit);
		else
			snprintf(print_uid, sizeof(print_uid),
				 "%s.%s.%04x.%02x", uid.vendor, uid.serial,
				 uid.ssid, uid.base_unit_addr);

		dev_info(&device->cdev->dev,
			 "An Alias device was reassigned to a new base device "
			 "with UID: %s\n", print_uid);
	}
	return 0;

out_err:
	return -1;
}

static struct ccw_driver dasd_eckd_driver = {
	.driver = {
		.name	= "dasd-eckd",
		.owner	= THIS_MODULE,
	},
	.ids	     = dasd_eckd_ids,
	.probe	     = dasd_eckd_probe,
	.remove      = dasd_generic_remove,
	.set_offline = dasd_generic_set_offline,
	.set_online  = dasd_eckd_set_online,
	.notify      = dasd_generic_notify,
	.path_event  = dasd_generic_path_event,
	.shutdown    = dasd_generic_shutdown,
	.freeze      = dasd_generic_pm_freeze,
	.thaw	     = dasd_generic_restore_device,
	.restore     = dasd_generic_restore_device,
	.uc_handler  = dasd_generic_uc_handler,
	.int_class   = IOINT_DAS,
};

/*
 * max_blocks is dependent on the amount of storage that is available
 * in the static io buffer for each device. Currently each device has
 * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
 * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
 * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
 * addition we have one define extent ccw + 16 bytes of data and one
 * locate record ccw + 16 bytes of data. That makes:
 * (8192 - 24 - 136 - 8 - 16 - 8 - 16) / 16 = 499 blocks at maximum.
 * We want to fit two into the available memory so that we can immediately
 * start the next request if one finishes off. That makes 249.5 blocks
 * for one request. Give a little safety and the result is 240.
 */
static struct dasd_discipline dasd_eckd_discipline = {
	.owner = THIS_MODULE,
	.name = "ECKD",
	.ebcname = "ECKD",
	.max_blocks = 190,
	.check_device = dasd_eckd_check_characteristics,
	.uncheck_device = dasd_eckd_uncheck_device,
	.do_analysis = dasd_eckd_do_analysis,
	.verify_path = dasd_eckd_verify_path,
	.ready_to_online = dasd_eckd_ready_to_online,
	.online_to_ready = dasd_eckd_online_to_ready,
	.fill_geometry = dasd_eckd_fill_geometry,
	.start_IO = dasd_start_IO,
	.term_IO = dasd_term_IO,
	.handle_terminated_request = dasd_eckd_handle_terminated_request,
	.format_device = dasd_eckd_format_device,
	.erp_action = dasd_eckd_erp_action,
	.erp_postaction = dasd_eckd_erp_postaction,
	.check_for_device_change = dasd_eckd_check_for_device_change,
	.build_cp = dasd_eckd_build_alias_cp,
	.free_cp = dasd_eckd_free_alias_cp,
	.dump_sense = dasd_eckd_dump_sense,
	.dump_sense_dbf = dasd_eckd_dump_sense_dbf,
	.fill_info = dasd_eckd_fill_info,
	.ioctl = dasd_eckd_ioctl,
	.freeze = dasd_eckd_pm_freeze,
	.restore = dasd_eckd_restore_device,
	.reload = dasd_eckd_reload_device,
	.get_uid = dasd_eckd_get_uid,
	.kick_validate = dasd_eckd_kick_validate_server,
};

static int __init
dasd_eckd_init(void)
{
	int ret;

	ASCEBC(dasd_eckd_discipline.ebcname, 4);
	dasd_reserve_req = kmalloc(sizeof(*dasd_reserve_req),
				   GFP_KERNEL | GFP_DMA);
	if (!dasd_reserve_req)
		return -ENOMEM;
	path_verification_worker = kmalloc(sizeof(*path_verification_worker),
				   GFP_KERNEL | GFP_DMA);
	if (!path_verification_worker) {
		kfree(dasd_reserve_req);
		return -ENOMEM;
	}
	ret = ccw_driver_register(&dasd_eckd_driver);
	if (!ret)
		wait_for_device_probe();
	else {
		kfree(path_verification_worker);
		kfree(dasd_reserve_req);
	}
	return ret;
}

static void __exit
dasd_eckd_cleanup(void)
{
	ccw_driver_unregister(&dasd_eckd_driver);
	kfree(path_verification_worker);
	kfree(dasd_reserve_req);
}

module_init(dasd_eckd_init);
module_exit(dasd_eckd_cleanup);