summaryrefslogtreecommitdiff
path: root/linux/dev/drivers/block/ide.c
blob: 5dcd0aa9ec2bcaee441e6394b3dfed1b3a19072b (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
/*
 *  linux/drivers/block/ide.c	Version 5.53  Jun  24, 1997
 *
 *  Copyright (C) 1994-1996  Linus Torvalds & authors (see below)
 */
#define _IDE_C		/* needed by <linux/blk.h> */

/*
 *  Maintained by Mark Lord  <mlord@pobox.com>
 *            and Gadi Oxman <gadio@netvision.net.il>
 *
 * This is the multiple IDE interface driver, as evolved from hd.c.
 * It supports up to four IDE interfaces, on one or more IRQs (usually 14 & 15).
 * There can be up to two drives per interface, as per the ATA-2 spec.
 *
 * Primary:    ide0, port 0x1f0; major=3;  hda is minor=0; hdb is minor=64
 * Secondary:  ide1, port 0x170; major=22; hdc is minor=0; hdd is minor=64
 * Tertiary:   ide2, port 0x???; major=33; hde is minor=0; hdf is minor=64
 * Quaternary: ide3, port 0x???; major=34; hdg is minor=0; hdh is minor=64
 *
 * It is easy to extend ide.c to handle more than four interfaces:
 *
 *	Change the MAX_HWIFS constant in ide.h.
 *
 *	Define some new major numbers (in major.h), and insert them into
 *	the ide_hwif_to_major table in ide.c.
 *
 *	Fill in the extra values for the new interfaces into the two tables
 *	inside ide.c:  default_io_base[]  and  default_irqs[].
 *
 *	Create the new request handlers by cloning "do_ide3_request()"
 *	for each new interface, and add them to the switch statement
 *	in the ide_init() function in ide.c.
 *
 *	Recompile, create the new /dev/ entries, and it will probably work.
 *
 *  From hd.c:
 *  |
 *  | It traverses the request-list, using interrupts to jump between functions.
 *  | As nearly all functions can be called within interrupts, we may not sleep.
 *  | Special care is recommended.  Have Fun!
 *  |
 *  | modified by Drew Eckhardt to check nr of hd's from the CMOS.
 *  |
 *  | Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
 *  | in the early extended-partition checks and added DM partitions.
 *  |
 *  | Early work on error handling by Mika Liljeberg (liljeber@cs.Helsinki.FI).
 *  |
 *  | IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
 *  | and general streamlining by Mark Lord (mlord@pobox.com).
 *
 *  October, 1994 -- Complete line-by-line overhaul for linux 1.1.x, by:
 *
 *	Mark Lord	(mlord@pobox.com)		(IDE Perf.Pkg)
 *	Delman Lee	(delman@mipg.upenn.edu)		("Mr. atdisk2")
 *	Scott Snyder	(snyder@fnald0.fnal.gov)	(ATAPI IDE cd-rom)
 *
 *  This was a rewrite of just about everything from hd.c, though some original
 *  code is still sprinkled about.  Think of it as a major evolution, with
 *  inspiration from lots of linux users, esp.  hamish@zot.apana.org.au
 *
 *  Version 1.0 ALPHA	initial code, primary i/f working okay
 *  Version 1.3 BETA	dual i/f on shared irq tested & working!
 *  Version 1.4 BETA	added auto probing for irq(s)
 *  Version 1.5 BETA	added ALPHA (untested) support for IDE cd-roms,
 *  ...
 *  Version 3.5		correct the bios_cyl field if it's too small
 *  (linux 1.1.76)	 (to help fdisk with brain-dead BIOSs)
 *  Version 3.6		cosmetic corrections to comments and stuff
 *  (linux 1.1.77)	reorganise probing code to make it understandable
 *			added halfway retry to probing for drive identification
 *			added "hdx=noprobe" command line option
 *			allow setting multmode even when identification fails
 *  Version 3.7		move set_geometry=1 from do_identify() to ide_init()
 *			increase DRQ_WAIT to eliminate nuisance messages
 *			wait for DRQ_STAT instead of DATA_READY during probing
 *			  (courtesy of Gary Thomas gary@efland.UU.NET)
 *  Version 3.8		fixed byte-swapping for confused Mitsumi cdrom drives
 *			update of ide-cd.c from Scott, allows blocksize=1024
 *			cdrom probe fixes, inspired by jprang@uni-duisburg.de
 *  Version 3.9		don't use LBA if lba_capacity looks funny
 *			correct the drive capacity calculations
 *			fix probing for old Seagates without IDE_ALTSTATUS_REG
 *			fix byte-ordering for some NEC cdrom drives
 *  Version 3.10	disable multiple mode by default; was causing trouble
 *  Version 3.11	fix mis-identification of old WD disks as cdroms
 *  Version 3,12	simplify logic for selecting initial mult_count
 *			  (fixes problems with buggy WD drives)
 *  Version 3.13	remove excess "multiple mode disabled" messages
 *  Version 3.14	fix ide_error() handling of BUSY_STAT
 *			fix byte-swapped cdrom strings (again.. arghh!)
 *			ignore INDEX bit when checking the ALTSTATUS reg
 *  Version 3.15	add SINGLE_THREADED flag for use with dual-CMD i/f
 *			ignore WRERR_STAT for non-write operations
 *			added vlb_sync support for DC-2000A & others,
 *			 (incl. some Promise chips), courtesy of Frank Gockel
 *  Version 3.16	convert vlb_32bit and vlb_sync into runtime flags
 *			add ioctls to get/set VLB flags (HDIO_[SG]ET_CHIPSET)
 *			rename SINGLE_THREADED to SUPPORT_SERIALIZE,
 *			add boot flag to "serialize" operation for CMD i/f
 *			add optional support for DTC2278 interfaces,
 *			 courtesy of andy@cercle.cts.com (Dyan Wile).
 *			add boot flag to enable "dtc2278" probe
 *			add probe to avoid EATA (SCSI) interfaces,
 *			 courtesy of neuffer@goofy.zdv.uni-mainz.de.
 *  Version 4.00	tidy up verify_area() calls - heiko@colossus.escape.de
 *			add flag to ignore WRERR_STAT for some drives
 *			 courtesy of David.H.West@um.cc.umich.edu
 *			assembly syntax tweak to vlb_sync
 *			removable drive support from scuba@cs.tu-berlin.de
 *			add transparent support for DiskManager-6.0x "Dynamic
 *			 Disk Overlay" (DDO), most of this is in genhd.c
 *			eliminate "multiple mode turned off" message at boot
 *  Version 4.10	fix bug in ioctl for "hdparm -c3"
 *			fix DM6:DDO support -- now works with LILO, fdisk, ...
 *			don't treat some naughty WD drives as removable
 *  Version 4.11	updated DM6 support using info provided by OnTrack
 *  Version 5.00	major overhaul, multmode setting fixed, vlb_sync fixed
 *			added support for 3rd/4th/alternative IDE ports
 *			created ide.h; ide-cd.c now compiles separate from ide.c
 *			hopefully fixed infinite "unexpected_intr" from cdroms
 *			zillions of other changes and restructuring
 *			somehow reduced overall memory usage by several kB
 *			probably slowed things down slightly, but worth it
 *  Version 5.01	AT LAST!!  Finally understood why "unexpected_intr"
 *			 was happening at various times/places:  whenever the
 *			 ide-interface's ctl_port was used to "mask" the irq,
 *			 it also would trigger an edge in the process of masking
 *			 which would result in a self-inflicted interrupt!!
 *			 (such a stupid way to build a hardware interrupt mask).
 *			 This is now fixed (after a year of head-scratching).
 *  Version 5.02	got rid of need for {enable,disable}_irq_list()
 *  Version 5.03	tune-ups, comments, remove "busy wait" from drive resets
 *			removed PROBE_FOR_IRQS option -- no longer needed
 *			OOOPS!  fixed "bad access" bug for 2nd drive on an i/f
 *  Version 5.04	changed "ira %d" to "irq %d" in DEBUG message
 *			added more comments, cleaned up unexpected_intr()
 *			OOOPS!  fixed null pointer problem in ide reset code
 *			added autodetect for Triton chipset -- no effect yet
 *  Version 5.05	OOOPS!  fixed bug in revalidate_disk()
 *			OOOPS!  fixed bug in ide_do_request()
 *			added ATAPI reset sequence for cdroms
 *  Version 5.10	added Bus-Mastered DMA support for Triton Chipset
 *			some (mostly) cosmetic changes
 *  Version 5.11	added ht6560b support by malafoss@snakemail.hut.fi
 *			reworked PCI scanning code
 *			added automatic RZ1000 detection/support
 *			added automatic PCI CMD640 detection/support
 *			added option for VLB CMD640 support
 *			tweaked probe to find cdrom on hdb with disks on hda,hdc
 *  Version 5.12	some performance tuning
 *			added message to alert user to bad /dev/hd[cd] entries
 *			OOOPS!  fixed bug in atapi reset
 *			driver now forces "serialize" again for all cmd640 chips
 *			noticed REALLY_SLOW_IO had no effect, moved it to ide.c
 *			made do_drive_cmd() into public ide_do_drive_cmd()
 *  Version 5.13	fixed typo ('B'), thanks to houston@boyd.geog.mcgill.ca
 *			fixed ht6560b support
 *  Version 5.13b (sss)	fix problem in calling ide_cdrom_setup()
 *			don't bother invalidating nonexistent partitions
 *  Version 5.14	fixes to cmd640 support.. maybe it works now(?)
 *			added & tested full EZ-DRIVE support -- don't use LILO!
 *			don't enable 2nd CMD640 PCI port during init - conflict
 *  Version 5.15	bug fix in init_cmd640_vlb()
 *			bug fix in interrupt sharing code
 *  Version 5.16	ugh.. fix "serialize" support, broken in 5.15
 *			remove "Huh?" from cmd640 code
 *			added qd6580 interface speed select from Colten Edwards
 *  Version 5.17	kludge around bug in BIOS32 on Intel triton motherboards
 *  Version 5.18	new CMD640 code, moved to cmd640.c, #include'd for now
 *			new UMC8672 code, moved to umc8672.c, #include'd for now
 *			disallow turning on DMA when h/w not capable of DMA
 *  Version 5.19	fix potential infinite timeout on resets
 *			extend reset poll into a general purpose polling scheme
 *			add atapi tape drive support from Gadi Oxman
 *			simplify exit from _intr routines -- no IDE_DO_REQUEST
 *  Version 5.20	leave current rq on blkdev request list during I/O
 *			generalized ide_do_drive_cmd() for tape/cdrom driver use
 *  Version 5.21	fix nasty cdrom/tape bug (ide_preempt was messed up)
 *  Version 5.22	fix ide_xlate_1024() to work with/without drive->id
 *  Version 5.23	miscellaneous touch-ups
 *  Version 5.24	fix #if's for SUPPORT_CMD640
 *  Version 5.25	more touch-ups, fix cdrom resets, ...
 *			cmd640.c now configs/compiles separate from ide.c
 *  Version 5.26	keep_settings now maintains the using_dma flag
 *			fix [EZD] remap message to only output at boot time
 *			fix "bad /dev/ entry" message to say hdc, not hdc0
 *			fix ide_xlate_1024() to respect user specified CHS
 *			use CHS from partn table if it looks translated
 *			re-merged flags chipset,vlb_32bit,vlb_sync into io_32bit
 *			keep track of interface chipset type, when known
 *			add generic PIO mode "tuneproc" mechanism
 *			fix cmd640_vlb option
 *			fix ht6560b support (was completely broken)
 *			umc8672.c now configures/compiles separate from ide.c
 *			move dtc2278 support to dtc2278.c
 *			move ht6560b support to ht6560b.c
 *			move qd6580  support to qd6580.c
 *			add  ali14xx support in ali14xx.c
 * Version 5.27		add [no]autotune parameters to help cmd640
 *			move rz1000  support to rz1000.c
 * Version 5.28		#include "ide_modes.h"
 *			fix disallow_unmask: now per-interface "no_unmask" bit
 *			force io_32bit to be the same on drive pairs of dtc2278
 *			improved IDE tape error handling, and tape DMA support
 *			bugfix in ide_do_drive_cmd() for cdroms + serialize
 * Version 5.29		fixed non-IDE check for too many physical heads
 *			don't use LBA if capacity is smaller than CHS
 * Version 5.30		remove real_devices kludge, formerly used by genhd.c
 * Version 5.32		change "KB" to "kB"
 *			fix serialize (was broken in kernel 1.3.72)
 *			add support for "hdparm -I"
 *			use common code for disk/tape/cdrom IDE_DRIVE_CMDs
 *			add support for Promise DC4030VL caching card
 *			improved serialize support
 *			put partition check back into alphabetical order
 *			add config option for PCMCIA baggage
 *			try to make PCMCIA support safer to use
 *			improve security on ioctls(): all are suser() only
 * Version 5.33		improve handling of HDIO_DRIVE_CMDs that read data
 * Version 5.34		fix irq-sharing problem from 5.33
 *			fix cdrom ioctl problem from 5.33
 * Version 5.35		cosmetic changes
 *			fix cli() problem in try_to_identify()
 * Version 5.36		fixes to optional PCMCIA support
 * Version 5.37		don't use DMA when "noautotune" is specified
 * Version 5.37a (go)	fix shared irq probing (was broken in kernel 1.3.72)
 *			call unplug_device() from ide_do_drive_cmd()
 * Version 5.38		add "hdx=none" option, courtesy of Joel Maslak
 *			mask drive irq after use, if sharing with another hwif
 *			add code to help debug weird cmd640 problems
 * Version 5.39		fix horrible error in earlier irq sharing "fix"
 * Version 5.40		fix serialization -- was broken in 5.39
 *			help sharing by masking device irq after probing
 * Version 5.41		more fixes to irq sharing/serialize detection
 *			disable io_32bit by default on drive reset
 * Version 5.42		simplify irq-masking after probe
 *			fix NULL pointer deref in save_match()
 * Version 5.43		Ugh.. unexpected_intr is back: try to exterminate it
 * Version 5.44		Fix for "irq probe failed" on cmd640
 *			change path on message regarding MAKEDEV.ide
 *			add a throttle to the unexpected_intr() messages
 * Version 5.45		fix ugly parameter parsing bugs (thanks Derek)
 *			include Gadi's magic fix for cmd640 unexpected_intr
 *			include mc68000 patches from Geert Uytterhoeven
 *			add Gadi's fix for PCMCIA cdroms
 * Version 5.46		remove the mc68000 #ifdefs for 2.0.x
 * Version 5.47		fix set_tune race condition
 *			fix bug in earlier PCMCIA cdrom update
 * Version 5.48		if def'd, invoke CMD640_DUMP_REGS when irq probe fails
 *			lengthen the do_reset1() pulse, for laptops
 *			add idebus=xx parameter for cmd640 and ali chipsets
 *			no_unmask flag now per-drive instead of per-hwif
 *			fix tune_req so that it gets done immediately
 *			fix missing restore_flags() in ide_ioctl
 *			prevent use of io_32bit on cmd640 with no prefetch
 * Version 5.49		fix minor quirks in probing routines
 * Version 5.50		allow values as small as 20 for idebus=
 * Version 5.51		force non io_32bit in drive_cmd_intr()
 *			change delay_10ms() to delay_50ms() to fix problems
 * Version 5.52		fix incorrect invalidation of removable devices
 *			add "hdx=slow" command line option
 * Version 5.53		add ATAPI floppy drive support
 *			change default media for type 0 to floppy
 *			add support for Exabyte Nest
 *			add missing set_blocksize() in revalidate_disk()
 *			handle bad status bit sequencing in ide_wait_stat()
 *			support partition table translations with 255 heads
 *			probe all interfaces by default
 *			add probe for the i82371AB chipset
 *			acknowledge media change on removable drives
 *			add work-around for BMI drives
 *			remove "LBA" from boot messages
 * Version 5.53.1	add UDMA "CRC retry" support
 * Version 5.53.2	add Promise/33 auto-detection and DMA support
 *			fix MC_ERR handling
 *			fix mis-detection of NEC cdrom as floppy
 *			issue ATAPI reset and re-probe after "no response"
 *
 *  Some additional driver compile-time options are in ide.h
 *
 *  To do, in likely order of completion:
 *	- modify kernel to obtain BIOS geometry for drives on 2nd/3rd/4th i/f
*/

#undef REALLY_SLOW_IO		/* most systems can safely undef this */

#include <linux/config.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/malloc.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/segment.h>
#include <asm/io.h>

#ifdef CONFIG_PCI
#include <linux/bios32.h>
#include <linux/pci.h>
#endif /* CONFIG_PCI */

#include "ide.h"
#include "ide_modes.h"

#ifdef CONFIG_BLK_DEV_PROMISE
#include "promise.h"
#define IS_PROMISE_DRIVE (HWIF(drive)->chipset == ide_promise)
#else
#define IS_PROMISE_DRIVE (0)	/* auto-NULLs out Promise code */
#endif /* CONFIG_BLK_DEV_PROMISE */

static const byte	ide_hwif_to_major[MAX_HWIFS] = {IDE0_MAJOR, IDE1_MAJOR, IDE2_MAJOR, IDE3_MAJOR};
static const unsigned short default_io_base[MAX_HWIFS] = {0x1f0, 0x170, 0x1e8, 0x168};
static const byte	default_irqs[MAX_HWIFS]     = {14, 15, 11, 10};
static int	idebus_parameter; /* holds the "idebus=" parameter */
static int	system_bus_speed; /* holds what we think is VESA/PCI bus speed */

/*
 * This is declared extern in ide.h, for access by other IDE modules:
 */
ide_hwif_t	ide_hwifs[MAX_HWIFS];	/* master data repository */

#if (DISK_RECOVERY_TIME > 0)
/*
 * For really screwy hardware (hey, at least it *can* be used with Linux)
 * we can enforce a minimum delay time between successive operations.
 */
static unsigned long read_timer(void)
{
	unsigned long t, flags;
	int i;

	save_flags(flags);
	cli();
	t = jiffies * 11932;
    	outb_p(0, 0x43);
	i = inb_p(0x40);
	i |= inb(0x40) << 8;
	restore_flags(flags);
	return (t - i);
}

static void set_recovery_timer (ide_hwif_t *hwif)
{
	hwif->last_time = read_timer();
}
#define SET_RECOVERY_TIMER(drive) set_recovery_timer (drive)

#else

#define SET_RECOVERY_TIMER(drive)

#endif /* DISK_RECOVERY_TIME */


/*
 * Do not even *think* about calling this!
 */
static void init_hwif_data (unsigned int index)
{
	byte *p;
	unsigned int unit;
	ide_hwif_t *hwif = &ide_hwifs[index];

	/* bulk initialize hwif & drive info with zeros */
	p = ((byte *) hwif) + sizeof(ide_hwif_t);
	do {
		*--p = 0;
	} while (p > (byte *) hwif);

	/* fill in any non-zero initial values */
	hwif->index     = index;
	hwif->io_base	= default_io_base[index];
	hwif->ctl_port	= hwif->io_base ? hwif->io_base+0x206 : 0x000;
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->io_base == HD_DATA)
		hwif->noprobe = 1; /* may be overridden by ide_setup() */
#endif /* CONFIG_BLK_DEV_HD */
	hwif->major	= ide_hwif_to_major[index];
	hwif->name[0]	= 'i';
	hwif->name[1]	= 'd';
	hwif->name[2]	= 'e';
	hwif->name[3]	= '0' + index;
#ifdef CONFIG_BLK_DEV_IDETAPE
	hwif->tape_drive = NULL;
#endif /* CONFIG_BLK_DEV_IDETAPE */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];

		drive->select.all		= (unit<<4)|0xa0;
		drive->hwif			= hwif;
		drive->ctl			= 0x08;
		drive->ready_stat		= READY_STAT;
		drive->bad_wstat		= BAD_W_STAT;
		drive->special.b.recalibrate	= 1;
		drive->special.b.set_geometry	= 1;
		drive->name[0]			= 'h';
		drive->name[1]			= 'd';
#ifdef MACH
		drive->name[2]			= '0' + (index * MAX_DRIVES) + unit;
#else
		drive->name[2]			= 'a' + (index * MAX_DRIVES) + unit;
#endif
	}
}

/*
 * init_ide_data() sets reasonable default values into all fields
 * of all instances of the hwifs and drives, but only on the first call.
 * Subsequent calls have no effect (they don't wipe out anything).
 *
 * This routine is normally called at driver initialization time,
 * but may also be called MUCH earlier during kernel "command-line"
 * parameter processing.  As such, we cannot depend on any other parts
 * of the kernel (such as memory allocation) to be functioning yet.
 *
 * This is too bad, as otherwise we could dynamically allocate the
 * ide_drive_t structs as needed, rather than always consuming memory
 * for the max possible number (MAX_HWIFS * MAX_DRIVES) of them.
 */
#define MAGIC_COOKIE 0x12345678
static void init_ide_data (void)
{
	unsigned int index;
	static unsigned long magic_cookie = MAGIC_COOKIE;

	if (magic_cookie != MAGIC_COOKIE)
		return;		/* already initialized */
	magic_cookie = 0;

	for (index = 0; index < MAX_HWIFS; ++index)
		init_hwif_data(index);

	idebus_parameter = 0;
	system_bus_speed = 0;
}

/*
 * ide_system_bus_speed() returns what we think is the system VESA/PCI
 * bus speed (in Mhz).  This is used for calculating interface PIO timings.
 * The default is 40 for known PCI systems, 50 otherwise.
 * The "idebus=xx" parameter can be used to override this value.
 * The actual value to be used is computed/displayed the first time through.
 */
int ide_system_bus_speed (void)
{
	if (!system_bus_speed) {
		if (idebus_parameter)
			system_bus_speed = idebus_parameter;	/* user supplied value */
#ifdef CONFIG_PCI
		else if (pcibios_present())
			system_bus_speed = 40;	/* safe default value for PCI */
#endif /* CONFIG_PCI */
		else
			system_bus_speed = 50;	/* safe default value for VESA and PCI */
		printk("ide: Assuming %dMhz system bus speed for PIO modes; override with idebus=xx\n", system_bus_speed);
	}
	return system_bus_speed;
}

#if SUPPORT_VLB_SYNC
/*
 * Some localbus EIDE interfaces require a special access sequence
 * when using 32-bit I/O instructions to transfer data.  We call this
 * the "vlb_sync" sequence, which consists of three successive reads
 * of the sector count register location, with interrupts disabled
 * to ensure that the reads all happen together.
 */
static inline void do_vlb_sync (unsigned short port) {
	(void) inb (port);
	(void) inb (port);
	(void) inb (port);
}
#endif /* SUPPORT_VLB_SYNC */

/*
 * This is used for most PIO data transfers *from* the IDE interface
 */
void ide_input_data (ide_drive_t *drive, void *buffer, unsigned int wcount)
{
	unsigned short io_base  = HWIF(drive)->io_base;
	unsigned short data_reg = io_base+IDE_DATA_OFFSET;
	byte io_32bit = drive->io_32bit;

	if (io_32bit) {
#if SUPPORT_VLB_SYNC
		if (io_32bit & 2) {
			cli();
			do_vlb_sync(io_base+IDE_NSECTOR_OFFSET);
			insl(data_reg, buffer, wcount);
			if (drive->unmask)
				sti();
		} else
#endif /* SUPPORT_VLB_SYNC */
			insl(data_reg, buffer, wcount);
	} else {
#if SUPPORT_SLOW_DATA_PORTS
		if (drive->slow) {
			unsigned short *ptr = (unsigned short *) buffer;
			while (wcount--) {
				*ptr++ = inw_p(data_reg);
				*ptr++ = inw_p(data_reg);
			}
		} else
#endif /* SUPPORT_SLOW_DATA_PORTS */
			insw(data_reg, buffer, wcount<<1);
	}
}

/*
 * This is used for most PIO data transfers *to* the IDE interface
 */
void ide_output_data (ide_drive_t *drive, void *buffer, unsigned int wcount)
{
	unsigned short io_base  = HWIF(drive)->io_base;
	unsigned short data_reg = io_base+IDE_DATA_OFFSET;
	byte io_32bit = drive->io_32bit;

	if (io_32bit) {
#if SUPPORT_VLB_SYNC
		if (io_32bit & 2) {
			cli();
			do_vlb_sync(io_base+IDE_NSECTOR_OFFSET);
			outsl(data_reg, buffer, wcount);
			if (drive->unmask)
				sti();
		} else
#endif /* SUPPORT_VLB_SYNC */
			outsl(data_reg, buffer, wcount);
	} else {
#if SUPPORT_SLOW_DATA_PORTS
		if (drive->slow) {
			unsigned short *ptr = (unsigned short *) buffer;
			while (wcount--) {
				outw_p(*ptr++, data_reg);
				outw_p(*ptr++, data_reg);
			}
		} else
#endif /* SUPPORT_SLOW_DATA_PORTS */
			outsw(data_reg, buffer, wcount<<1);
	}
}

/*
 * The following routines are mainly used by the ATAPI drivers.
 *
 * These routines will round up any request for an odd number of bytes,
 * so if an odd bytecount is specified, be sure that there's at least one
 * extra byte allocated for the buffer.
 */
void atapi_input_bytes (ide_drive_t *drive, void *buffer, unsigned int bytecount)
{
	++bytecount;
	ide_input_data (drive, buffer, bytecount / 4);
	if ((bytecount & 0x03) >= 2)
		insw (IDE_DATA_REG, ((byte *)buffer) + (bytecount & ~0x03), 1);
}

void atapi_output_bytes (ide_drive_t *drive, void *buffer, unsigned int bytecount)
{
	++bytecount;
	ide_output_data (drive, buffer, bytecount / 4);
	if ((bytecount & 0x03) >= 2)
		outsw (IDE_DATA_REG, ((byte *)buffer) + (bytecount & ~0x03), 1);
}

/*
 * This should get invoked any time we exit the driver to
 * wait for an interrupt response from a drive.  handler() points
 * at the appropriate code to handle the next interrupt, and a
 * timer is started to prevent us from waiting forever in case
 * something goes wrong (see the timer_expiry() handler later on).
 */
void ide_set_handler (ide_drive_t *drive, ide_handler_t *handler, unsigned int timeout)
{
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
#ifdef DEBUG
	if (hwgroup->handler != NULL) {
		printk("%s: ide_set_handler: handler not null; old=%p, new=%p\n",
			drive->name, hwgroup->handler, handler);
	}
#endif
	hwgroup->handler       = handler;
	hwgroup->timer.expires = jiffies + timeout;
	add_timer(&(hwgroup->timer));
}

/*
 * lba_capacity_is_ok() performs a sanity check on the claimed "lba_capacity"
 * value for this drive (from its reported identification information).
 *
 * Returns:	1 if lba_capacity looks sensible
 *		0 otherwise
 */
static int lba_capacity_is_ok (struct hd_driveid *id)
{
	unsigned long lba_sects   = id->lba_capacity;
	unsigned long chs_sects   = id->cyls * id->heads * id->sectors;
	unsigned long _10_percent = chs_sects / 10;

	/* very large drives (8GB+) may lie about the number of cylinders */
	if (id->cyls == 16383 && id->heads == 16 && id->sectors == 63 && lba_sects > chs_sects) {
		return 1;	/* lba_capacity is our only option */
	}
	/* perform a rough sanity check on lba_sects:  within 10% is "okay" */
	if ((lba_sects - chs_sects) < _10_percent)
		return 1;	/* lba_capacity is good */

	/* some drives have the word order reversed */
	lba_sects = (lba_sects << 16) | (lba_sects >> 16);
	if ((lba_sects - chs_sects) < _10_percent) {
		id->lba_capacity = lba_sects;	/* fix it */
		return 1;	/* lba_capacity is (now) good */
	}
	return 0;	/* lba_capacity value is bad */
}

/*
 * current_capacity() returns the capacity (in sectors) of a drive
 * according to its current geometry/LBA settings.
 */
static unsigned long current_capacity (ide_drive_t  *drive)
{
	struct hd_driveid *id = drive->id;
	unsigned long capacity = drive->cyl * drive->head * drive->sect;

	if (!drive->present)
		return 0;
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
	if (drive->media == ide_floppy)
		return idefloppy_capacity(drive);
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
	if (drive->media != ide_disk)
		return 0x7fffffff;	/* cdrom or tape */
	drive->select.b.lba = 0;
	/* Determine capacity, and use LBA if the drive properly supports it */
	if (id != NULL && (id->capability & 2) && lba_capacity_is_ok(id)) {
		if (id->lba_capacity >= capacity) {
			capacity = id->lba_capacity;
			drive->select.b.lba = 1;
		}
	}
	return (capacity - drive->sect0);
}

/*
 * ide_geninit() is called exactly *once* for each major, from genhd.c,
 * at the beginning of the initial partition check for the drives.
 */
static void ide_geninit (struct gendisk *gd)
{
	unsigned int unit;
	ide_hwif_t *hwif = gd->real_devices;

	for (unit = 0; unit < gd->nr_real; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
#ifdef CONFIG_BLK_DEV_IDECD
		if (drive->present && drive->media == ide_cdrom)
			ide_cdrom_setup(drive);
#endif /* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDETAPE
		if (drive->present && drive->media == ide_tape)
			idetape_setup(drive);
#endif /* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
		if (drive->present && drive->media == ide_floppy)
			idefloppy_setup(drive);
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
		drive->part[0].nr_sects = current_capacity(drive);
		if (!drive->present || (drive->media != ide_disk && drive->media != ide_floppy) ||
		    !drive->part[0].nr_sects) {
			drive->part[0].start_sect = -1; /* skip partition check */
		}
	}
}

/*
 * init_gendisk() (as opposed to ide_geninit) is called for each major device,
 * after probing for drives, to allocate partition tables and other data
 * structures needed for the routines in genhd.c.  ide_geninit() gets called
 * somewhat later, during the partition check.
 */
static void init_gendisk (ide_hwif_t *hwif)
{
	struct gendisk *gd, **gdp;
	unsigned int unit, units, minors;
	int *bs;

	/* figure out maximum drive number on the interface */
	for (units = MAX_DRIVES; units > 0; --units) {
		if (hwif->drives[units-1].present)
			break;
	}
	minors    = units * (1<<PARTN_BITS);
	gd        = kmalloc (sizeof(struct gendisk), GFP_KERNEL);
	gd->sizes = kmalloc (minors * sizeof(int), GFP_KERNEL);
	gd->part  = kmalloc (minors * sizeof(struct hd_struct), GFP_KERNEL);
	bs        = kmalloc (minors*sizeof(int), GFP_KERNEL);

	memset(gd->part, 0, minors * sizeof(struct hd_struct));

	/* cdroms and msdos f/s are examples of non-1024 blocksizes */
	blksize_size[hwif->major] = bs;
	for (unit = 0; unit < minors; ++unit)
		*bs++ = BLOCK_SIZE;

	for (unit = 0; unit < units; ++unit)
		hwif->drives[unit].part = &gd->part[unit << PARTN_BITS];

	gd->major	= hwif->major;		/* our major device number */
	gd->major_name	= IDE_MAJOR_NAME;	/* treated special in genhd.c */
	gd->minor_shift	= PARTN_BITS;		/* num bits for partitions */
	gd->max_p	= 1<<PARTN_BITS;	/* 1 + max partitions / drive */
	gd->max_nr	= units;		/* max num real drives */
	gd->nr_real	= units;		/* current num real drives */
	gd->init	= ide_geninit;		/* initialization function */
	gd->real_devices= hwif;			/* ptr to internal data */
	gd->next	= NULL;			/* linked list of major devs */

	for (gdp = &gendisk_head; *gdp; gdp = &((*gdp)->next)) ;
	hwif->gd = *gdp = gd;			/* link onto tail of list */
}

static void do_reset1 (ide_drive_t *, int);		/* needed below */

#ifdef CONFIG_BLK_DEV_IDEATAPI
/*
 * atapi_reset_pollfunc() gets invoked to poll the interface for completion every 50ms
 * during an atapi drive reset operation. If the drive has not yet responded,
 * and we have not yet hit our maximum waiting time, then the timer is restarted
 * for another 50ms.
 */
static void atapi_reset_pollfunc (ide_drive_t *drive)
{
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
	byte stat;

	OUT_BYTE (drive->select.all, IDE_SELECT_REG);
	udelay (10);

	if (OK_STAT(stat=GET_STAT(), 0, BUSY_STAT)) {
		printk("%s: ATAPI reset complete\n", drive->name);
	} else {
		if (jiffies < hwgroup->poll_timeout) {
			ide_set_handler (drive, &atapi_reset_pollfunc, HZ/20);
			return;	/* continue polling */
		}
		hwgroup->poll_timeout = 0;	/* end of polling */
		printk("%s: ATAPI reset timed-out, status=0x%02x\n", drive->name, stat);
		do_reset1 (drive, 1);	/* do it the old fashioned way */
		return;
	}
	hwgroup->poll_timeout = 0;	/* done polling */
}
#endif /* CONFIG_BLK_DEV_IDEATAPI */

/*
 * reset_pollfunc() gets invoked to poll the interface for completion every 50ms
 * during an ide reset operation. If the drives have not yet responded,
 * and we have not yet hit our maximum waiting time, then the timer is restarted
 * for another 50ms.
 */
static void reset_pollfunc (ide_drive_t *drive)
{
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
	ide_hwif_t *hwif = HWIF(drive);
	byte tmp;

	if (!OK_STAT(tmp=GET_STAT(), 0, BUSY_STAT)) {
		if (jiffies < hwgroup->poll_timeout) {
			ide_set_handler (drive, &reset_pollfunc, HZ/20);
			return;	/* continue polling */
		}
		printk("%s: reset timed-out, status=0x%02x\n", hwif->name, tmp);
	} else  {
		printk("%s: reset: ", hwif->name);
		if ((tmp = GET_ERR()) == 1)
			printk("success\n");
		else {
#if FANCY_STATUS_DUMPS
			printk("master: ");
			switch (tmp & 0x7f) {
				case 1: printk("passed");
					break;
				case 2: printk("formatter device error");
					break;
				case 3: printk("sector buffer error");
					break;
				case 4: printk("ECC circuitry error");
					break;
				case 5: printk("controlling MPU error");
					break;
				default:printk("error (0x%02x?)", tmp);
			}
			if (tmp & 0x80)
				printk("; slave: failed");
			printk("\n");
#else
			printk("failed\n");
#endif /* FANCY_STATUS_DUMPS */
		}
	}
	hwgroup->poll_timeout = 0;	/* done polling */
}

/*
 * do_reset1() attempts to recover a confused drive by resetting it.
 * Unfortunately, resetting a disk drive actually resets all devices on
 * the same interface, so it can really be thought of as resetting the
 * interface rather than resetting the drive.
 *
 * ATAPI devices have their own reset mechanism which allows them to be
 * individually reset without clobbering other devices on the same interface.
 *
 * Unfortunately, the IDE interface does not generate an interrupt to let
 * us know when the reset operation has finished, so we must poll for this.
 * Equally poor, though, is the fact that this may a very long time to complete,
 * (up to 30 seconds worstcase).  So, instead of busy-waiting here for it,
 * we set a timer to poll at 50ms intervals.
 */
static void do_reset1 (ide_drive_t *drive, int  do_not_try_atapi)
{
	unsigned int unit;
	unsigned long flags;
	ide_hwif_t *hwif = HWIF(drive);
	ide_hwgroup_t *hwgroup = HWGROUP(drive);

	save_flags(flags);
	cli();		/* Why ? */

#ifdef CONFIG_BLK_DEV_IDEATAPI
	/* For an ATAPI device, first try an ATAPI SRST. */
	if (drive->media != ide_disk) {
		if (!do_not_try_atapi) {
			if (!drive->keep_settings) {
				drive->unmask = 0;
				drive->io_32bit = 0;
			}
			OUT_BYTE (drive->select.all, IDE_SELECT_REG);
			udelay (20);
			OUT_BYTE (WIN_SRST, IDE_COMMAND_REG);
			hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
			ide_set_handler (drive, &atapi_reset_pollfunc, HZ/20);
			restore_flags (flags);
			return;
		}
	}
#endif /* CONFIG_BLK_DEV_IDEATAPI */

	/*
	 * First, reset any device state data we were maintaining
	 * for any of the drives on this interface.
	 */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *rdrive = &hwif->drives[unit];
#ifdef CONFIG_BLK_DEV_IDETAPE
		if (rdrive->media == ide_tape)
			rdrive->tape.reset_issued = 1;
#endif /* CONFIG_BLK_DEV_IDETAPE */
		rdrive->special.all = 0;
		rdrive->special.b.set_geometry = 1;
		rdrive->special.b.recalibrate  = 1;
		if (OK_TO_RESET_CONTROLLER)
			rdrive->mult_count = 0;
		if (!rdrive->keep_settings) {
			rdrive->mult_req = 0;
			rdrive->unmask = 0;
			rdrive->io_32bit = 0;
			if (rdrive->using_dma) {
				rdrive->using_dma = 0;
				printk("%s: disabled DMA\n", rdrive->name);
			}
		}
		if (rdrive->mult_req != rdrive->mult_count)
			rdrive->special.b.set_multmode = 1;
	}

#if OK_TO_RESET_CONTROLLER
	/*
	 * Note that we also set nIEN while resetting the device,
	 * to mask unwanted interrupts from the interface during the reset.
	 * However, due to the design of PC hardware, this will cause an
	 * immediate interrupt due to the edge transition it produces.
	 * This single interrupt gives us a "fast poll" for drives that
	 * recover from reset very quickly, saving us the first 50ms wait time.
	 */
	OUT_BYTE(drive->ctl|6,IDE_CONTROL_REG);	/* set SRST and nIEN */
	udelay(10);			/* more than enough time */
	OUT_BYTE(drive->ctl|2,IDE_CONTROL_REG);	/* clear SRST, leave nIEN */
	udelay(10);			/* more than enough time */
	hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
	ide_set_handler (drive, &reset_pollfunc, HZ/20);
#endif	/* OK_TO_RESET_CONTROLLER */

	restore_flags (flags);
}

/*
 * ide_do_reset() is the entry point to the drive/interface reset code.
 */
void ide_do_reset (ide_drive_t *drive)
{
	do_reset1 (drive, 0);
#ifdef CONFIG_BLK_DEV_IDETAPE
	if (drive->media == ide_tape)
		drive->tape.reset_issued=1;
#endif /* CONFIG_BLK_DEV_IDETAPE */
}

/*
 * Clean up after success/failure of an explicit drive cmd
 */
void ide_end_drive_cmd (ide_drive_t *drive, byte stat, byte err)
{
	unsigned long flags;
	struct request *rq = HWGROUP(drive)->rq;

	if (rq->cmd == IDE_DRIVE_CMD) {
		byte *args = (byte *) rq->buffer;
		rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
		if (args) {
			args[0] = stat;
			args[1] = err;
			args[2] = IN_BYTE(IDE_NSECTOR_REG);
		}
	}
	save_flags(flags);
	cli();
	blk_dev[MAJOR(rq->rq_dev)].current_request = rq->next;
	HWGROUP(drive)->rq = NULL;
	rq->rq_status = RQ_INACTIVE;
	if (rq->sem != NULL)
		up(rq->sem);
	restore_flags(flags);
}

/*
 * Error reporting, in human readable form (luxurious, but a memory hog).
 */
byte ide_dump_status (ide_drive_t *drive, const char *msg, byte stat)
{
	unsigned long flags;
	byte err = 0;

	save_flags (flags);
	sti();
	printk("%s: %s: status=0x%02x", drive->name, msg, stat);
#if FANCY_STATUS_DUMPS
	if (drive->media == ide_disk) {
		printk(" { ");
		if (stat & BUSY_STAT)
			printk("Busy ");
		else {
			if (stat & READY_STAT)	printk("DriveReady ");
			if (stat & WRERR_STAT)	printk("DeviceFault ");
			if (stat & SEEK_STAT)	printk("SeekComplete ");
			if (stat & DRQ_STAT)	printk("DataRequest ");
			if (stat & ECC_STAT)	printk("CorrectedError ");
			if (stat & INDEX_STAT)	printk("Index ");
			if (stat & ERR_STAT)	printk("Error ");
		}
		printk("}");
	}
#endif	/* FANCY_STATUS_DUMPS */
	printk("\n");
	if ((stat & (BUSY_STAT|ERR_STAT)) == ERR_STAT) {
		err = GET_ERR();
		printk("%s: %s: error=0x%02x", drive->name, msg, err);
#if FANCY_STATUS_DUMPS
		if (drive->media == ide_disk) {
			printk(" { ");
			if (err & ICRC_ERR)	printk((err & ABRT_ERR) ? "BadCRC " : "BadSector ");
			if (err & ECC_ERR)	printk("UncorrectableError ");
			if (err & ID_ERR)	printk("SectorIdNotFound ");
			if (err & ABRT_ERR)	printk("DriveStatusError ");
			if (err & TRK0_ERR)	printk("TrackZeroNotFound ");
			if (err & MARK_ERR)	printk("AddrMarkNotFound ");
			printk("}");
			if (err & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
				byte cur = IN_BYTE(IDE_SELECT_REG);
				if (cur & 0x40) {	/* using LBA? */
					printk(", LBAsect=%ld", (unsigned long)
					 ((cur&0xf)<<24)
					 |(IN_BYTE(IDE_HCYL_REG)<<16)
					 |(IN_BYTE(IDE_LCYL_REG)<<8)
					 | IN_BYTE(IDE_SECTOR_REG));
				} else {
					printk(", CHS=%d/%d/%d",
					 (IN_BYTE(IDE_HCYL_REG)<<8) +
					  IN_BYTE(IDE_LCYL_REG),
					  cur & 0xf,
					  IN_BYTE(IDE_SECTOR_REG));
				}
				if (HWGROUP(drive)->rq)
					printk(", sector=%ld", HWGROUP(drive)->rq->sector);
			}
		}
#endif	/* FANCY_STATUS_DUMPS */
		printk("\n");
	}
	restore_flags (flags);
	return err;
}

/*
 * try_to_flush_leftover_data() is invoked in response to a drive
 * unexpectedly having its DRQ_STAT bit set.  As an alternative to
 * resetting the drive, this routine tries to clear the condition
 * by read a sector's worth of data from the drive.  Of course,
 * this may not help if the drive is *waiting* for data from *us*.
 */
static void try_to_flush_leftover_data (ide_drive_t *drive)
{
	int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;

	while (i > 0) {
		unsigned long buffer[16];
		unsigned int wcount = (i > 16) ? 16 : i;
		i -= wcount;
		ide_input_data (drive, buffer, wcount);
	}
}

/*
 * ide_error() takes action based on the error returned by the controller.
 */
void ide_error (ide_drive_t *drive, const char *msg, byte stat)
{
	struct request *rq;
	byte err;

	err = ide_dump_status(drive, msg, stat);
	if ((rq = HWGROUP(drive)->rq) == NULL || drive == NULL)
		return;
	/* retry only "normal" I/O: */
	if (rq->cmd == IDE_DRIVE_CMD) {
		rq->errors = 1;
		ide_end_drive_cmd(drive, stat, err);
		return;
	}
	if (stat & BUSY_STAT) {		/* other bits are useless when BUSY */
		rq->errors |= ERROR_RESET;
	} else {
		if (drive->media == ide_disk && (stat & ERR_STAT)) {
			/* err has different meaning on cdrom and tape */
			if (err == ABRT_ERR) {
				if (drive->select.b.lba && IN_BYTE(IDE_COMMAND_REG) == WIN_SPECIFY)
					return;	/* some newer drives don't support WIN_SPECIFY */
			} else if ((err & (ABRT_ERR | ICRC_ERR)) == (ABRT_ERR | ICRC_ERR))
				; /* UDMA crc error -- just retry the operation */
			else if (err & (BBD_ERR | ECC_ERR))	/* retries won't help these */
				rq->errors = ERROR_MAX;
			else if (err & TRK0_ERR)	/* help it find track zero */
				rq->errors |= ERROR_RECAL;
			else if (err & MC_ERR)
				drive->special.b.mc = 1;
		}
		if ((stat & DRQ_STAT) && rq->cmd != WRITE)
			try_to_flush_leftover_data(drive);
	}
	if (GET_STAT() & (BUSY_STAT|DRQ_STAT))
		rq->errors |= ERROR_RESET;	/* Mmmm.. timing problem */

	if (rq->errors >= ERROR_MAX) {
#ifdef CONFIG_BLK_DEV_IDETAPE
		if (drive->media == ide_tape) {
			rq->errors = 0;
			idetape_end_request(0, HWGROUP(drive));
		} else
#endif /* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
		if (drive->media == ide_floppy) {
			rq->errors = 0;
			idefloppy_end_request(0, HWGROUP(drive));
		} else
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
#ifdef CONFIG_BLK_DEV_IDESCSI
		if (drive->media == ide_scsi) {
			rq->errors = 0;
			idescsi_end_request(0, HWGROUP(drive));
		} else
#endif /* CONFIG_BLK_DEV_IDESCSI */
 		ide_end_request(0, HWGROUP(drive));
	}
	else {
		if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
			++rq->errors;
			ide_do_reset(drive);
			return;
		} else if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
			drive->special.b.recalibrate = 1;
		++rq->errors;
	}
}

/*
 * read_intr() is the handler for disk read/multread interrupts
 */
static void read_intr (ide_drive_t *drive)
{
	byte stat;
	int i;
	unsigned int msect, nsect;
	struct request *rq;

	if (!OK_STAT(stat=GET_STAT(),DATA_READY,BAD_R_STAT)) {
		ide_error(drive, "read_intr", stat);
		return;
	}
	msect = drive->mult_count;
read_next:
	rq = HWGROUP(drive)->rq;
	if (msect) {
		if ((nsect = rq->current_nr_sectors) > msect)
			nsect = msect;
		msect -= nsect;
	} else
		nsect = 1;
	i = rq->nr_sectors - nsect;
	if (i > 0 && !msect)
		ide_set_handler (drive, &read_intr, WAIT_CMD);
	ide_input_data(drive, rq->buffer, nsect * SECTOR_WORDS);
#ifdef DEBUG
	printk("%s:  read: sectors(%ld-%ld), buffer=0x%08lx, remaining=%ld\n",
		drive->name, rq->sector, rq->sector+nsect-1,
		(unsigned long) rq->buffer+(nsect<<9), rq->nr_sectors-nsect);
#endif
	rq->sector += nsect;
	rq->buffer += nsect<<9;
	rq->errors = 0;
	rq->nr_sectors = i;
	if ((rq->current_nr_sectors -= nsect) <= 0)
		ide_end_request(1, HWGROUP(drive));
	if (i > 0 && msect)
		goto read_next;
}

/*
 * write_intr() is the handler for disk write interrupts
 */
static void write_intr (ide_drive_t *drive)
{
	byte stat;
	int i;
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
	struct request *rq = hwgroup->rq;

	if (OK_STAT(stat=GET_STAT(),DRIVE_READY,drive->bad_wstat)) {
#ifdef DEBUG
		printk("%s: write: sector %ld, buffer=0x%08lx, remaining=%ld\n",
			drive->name, rq->sector, (unsigned long) rq->buffer,
			rq->nr_sectors-1);
#endif
		if ((rq->nr_sectors == 1) ^ ((stat & DRQ_STAT) != 0)) {
			rq->sector++;
			rq->buffer += 512;
			rq->errors = 0;
			i = --rq->nr_sectors;
			--rq->current_nr_sectors;
			if (rq->current_nr_sectors <= 0)
				ide_end_request(1, hwgroup);
			if (i > 0) {
				ide_set_handler (drive, &write_intr, WAIT_CMD);
				ide_output_data (drive, rq->buffer, SECTOR_WORDS);
			}
			return;
		}
	}
	ide_error(drive, "write_intr", stat);
}

/*
 * ide_multwrite() transfers a block of up to mcount sectors of data
 * to a drive as part of a disk multiple-sector write operation.
 */
void ide_multwrite (ide_drive_t *drive, unsigned int mcount)
{
	struct request *rq = &HWGROUP(drive)->wrq;

	do {
		unsigned int nsect = rq->current_nr_sectors;
		if (nsect > mcount)
			nsect = mcount;
		mcount -= nsect;

		ide_output_data(drive, rq->buffer, nsect<<7);
#ifdef DEBUG
		printk("%s: multwrite: sector %ld, buffer=0x%08lx, count=%d, remaining=%ld\n",
			drive->name, rq->sector, (unsigned long) rq->buffer,
			nsect, rq->nr_sectors - nsect);
#endif
		if ((rq->nr_sectors -= nsect) <= 0)
			break;
		if ((rq->current_nr_sectors -= nsect) == 0) {
			if ((rq->bh = rq->bh->b_reqnext) != NULL) {
				rq->current_nr_sectors = rq->bh->b_size>>9;
				rq->buffer             = rq->bh->b_data;
			} else {
				panic("%s: buffer list corrupted\n", drive->name);
				break;
			}
		} else {
			rq->buffer += nsect << 9;
		}
	} while (mcount);
}

/*
 * multwrite_intr() is the handler for disk multwrite interrupts
 */
static void multwrite_intr (ide_drive_t *drive)
{
	byte stat;
	int i;
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
	struct request *rq = &hwgroup->wrq;

	if (OK_STAT(stat=GET_STAT(),DRIVE_READY,drive->bad_wstat)) {
		if (stat & DRQ_STAT) {
			if (rq->nr_sectors) {
				ide_set_handler (drive, &multwrite_intr, WAIT_CMD);
				ide_multwrite(drive, drive->mult_count);
				return;
			}
		} else {
			if (!rq->nr_sectors) {	/* all done? */
				rq = hwgroup->rq;
				for (i = rq->nr_sectors; i > 0;){
					i -= rq->current_nr_sectors;
					ide_end_request(1, hwgroup);
				}
				return;
			}
		}
	}
	ide_error(drive, "multwrite_intr", stat);
}

/*
 * Issue a simple drive command
 * The drive must be selected beforehand.
 */
static void ide_cmd(ide_drive_t *drive, byte cmd, byte nsect, ide_handler_t *handler)
{
	ide_set_handler (drive, handler, WAIT_CMD);
	OUT_BYTE(drive->ctl,IDE_CONTROL_REG);
	OUT_BYTE(nsect,IDE_NSECTOR_REG);
	OUT_BYTE(cmd,IDE_COMMAND_REG);
}

/*
 * set_multmode_intr() is invoked on completion of a WIN_SETMULT cmd.
 */
static void set_multmode_intr (ide_drive_t *drive)
{
	byte stat = GET_STAT();

	sti();
	if (OK_STAT(stat,READY_STAT,BAD_STAT)) {
		drive->mult_count = drive->mult_req;
	} else {
		drive->mult_req = drive->mult_count = 0;
		drive->special.b.recalibrate = 1;
		(void) ide_dump_status(drive, "set_multmode", stat);
	}
}

/*
 * set_geometry_intr() is invoked on completion of a WIN_SPECIFY cmd.
 */
static void set_geometry_intr (ide_drive_t *drive)
{
	byte stat = GET_STAT();

	sti();
	if (!OK_STAT(stat,READY_STAT,BAD_STAT))
		ide_error(drive, "set_geometry_intr", stat);
}

/*
 * recal_intr() is invoked on completion of a WIN_RESTORE (recalibrate) cmd.
 */
static void recal_intr (ide_drive_t *drive)
{
	byte stat = GET_STAT();

	sti();
	if (!OK_STAT(stat,READY_STAT,BAD_STAT))
		ide_error(drive, "recal_intr", stat);
}

/*
 * mc_intr() is invoked on completion of a WIN_ACKMC cmd.
 */
static void mc_intr (ide_drive_t *drive)
{
	byte stat = GET_STAT();

	sti();
	if (!OK_STAT(stat,READY_STAT,BAD_STAT))
		ide_error(drive, "mc_intr", stat);
	drive->special.b.mc = 0;
}

/*
 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
 */
static void drive_cmd_intr (ide_drive_t *drive)
{
	struct request *rq = HWGROUP(drive)->rq;
	byte *args = (byte *) rq->buffer;
	byte stat = GET_STAT();

	sti();
	if ((stat & DRQ_STAT) && args && args[3]) {
		byte io_32bit = drive->io_32bit;
		drive->io_32bit = 0;
		ide_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
		drive->io_32bit = io_32bit;
		stat = GET_STAT();
	}
	if (OK_STAT(stat,READY_STAT,BAD_STAT))
		ide_end_drive_cmd (drive, stat, GET_ERR());
	else
		ide_error(drive, "drive_cmd", stat); /* calls ide_end_drive_cmd */
}

/*
 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
 * commands to a drive.  It used to do much more, but has been scaled back.
 */
static inline void do_special (ide_drive_t *drive)
{
	special_t *s = &drive->special;

#ifdef DEBUG
	printk("%s: do_special: 0x%02x\n", drive->name, s->all);
#endif
	if (s->b.set_geometry) {
		s->b.set_geometry = 0;
		if (drive->media == ide_disk && !drive->no_geom) {
			OUT_BYTE(drive->sect,IDE_SECTOR_REG);
			OUT_BYTE(drive->cyl,IDE_LCYL_REG);
			OUT_BYTE(drive->cyl>>8,IDE_HCYL_REG);
			OUT_BYTE(((drive->head-1)|drive->select.all)&0xBF,IDE_SELECT_REG);
			if (!IS_PROMISE_DRIVE)
				ide_cmd(drive, WIN_SPECIFY, drive->sect, &set_geometry_intr);
		}
	} else if (s->b.recalibrate) {
		s->b.recalibrate = 0;
		if (drive->media == ide_disk && !IS_PROMISE_DRIVE)
			ide_cmd(drive, WIN_RESTORE, drive->sect, &recal_intr);
	} else if (s->b.set_tune) {
		ide_tuneproc_t *tuneproc = HWIF(drive)->tuneproc;
		s->b.set_tune = 0;
		if (tuneproc != NULL)
			tuneproc(drive, drive->tune_req);
	} else if (s->b.set_multmode) {
		s->b.set_multmode = 0;
		if (drive->media == ide_disk) {
			if (drive->id && drive->mult_req > drive->id->max_multsect)
				drive->mult_req = drive->id->max_multsect;
			if (!IS_PROMISE_DRIVE)
				ide_cmd(drive, WIN_SETMULT, drive->mult_req, &set_multmode_intr);
		} else
			drive->mult_req = 0;
	} else if (s->b.mc) {
		s->b.mc = 0;
		if (drive->media == ide_disk && !IS_PROMISE_DRIVE)
			ide_cmd(drive, WIN_ACKMC, drive->sect, &mc_intr);
	} else if (s->all) {
		int special = s->all;
		s->all = 0;
		printk("%s: bad special flag: 0x%02x\n", drive->name, special);
	}
}

/*
 * This routine busy-waits for the drive status to be not "busy".
 * It then checks the status for all of the "good" bits and none
 * of the "bad" bits, and if all is okay it returns 0.  All other
 * cases return 1 after invoking ide_error() -- caller should just return.
 *
 * This routine should get fixed to not hog the cpu during extra long waits..
 * That could be done by busy-waiting for the first jiffy or two, and then
 * setting a timer to wake up at half second intervals thereafter,
 * until timeout is achieved, before timing out.
 */
int ide_wait_stat (ide_drive_t *drive, byte good, byte bad, unsigned long timeout)
{
	byte stat;
	unsigned long flags;

	udelay(1);	/* spec allows drive 400ns to assert "BUSY" */
	if ((stat = GET_STAT()) & BUSY_STAT) {
		save_flags(flags);
		sti();
		timeout += jiffies;
		while ((stat = GET_STAT()) & BUSY_STAT) {
			if (jiffies > timeout) {
				restore_flags(flags);
				ide_error(drive, "status timeout", stat);
				return 1;
			}
		}
		restore_flags(flags);
	}
	udelay(1);	/* allow status to settle, then read it again */
	if (OK_STAT((stat = GET_STAT()), good, bad))
		return 0;
	ide_error(drive, "status error", stat);
	return 1;
}

/*
 * do_rw_disk() issues READ and WRITE commands to a disk,
 * using LBA if supported, or CHS otherwise, to address sectors.
 * It also takes care of issuing special DRIVE_CMDs.
 */
static inline void do_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
{
	ide_hwif_t *hwif = HWIF(drive);
	unsigned short io_base = hwif->io_base;
#ifdef CONFIG_BLK_DEV_PROMISE
	int use_promise_io = 0;
#endif /* CONFIG_BLK_DEV_PROMISE */

	OUT_BYTE(drive->ctl,IDE_CONTROL_REG);
	OUT_BYTE(rq->nr_sectors,io_base+IDE_NSECTOR_OFFSET);
#ifdef CONFIG_BLK_DEV_PROMISE
	if (IS_PROMISE_DRIVE) {
		if (hwif->is_promise2 || rq->cmd == READ) {
			use_promise_io = 1;
		}
	}
	if (drive->select.b.lba || use_promise_io) {
#else /* !CONFIG_BLK_DEV_PROMISE */
	if (drive->select.b.lba) {
#endif /* CONFIG_BLK_DEV_PROMISE */
#ifdef DEBUG
		printk("%s: %sing: LBAsect=%ld, sectors=%ld, buffer=0x%08lx\n",
			drive->name, (rq->cmd==READ)?"read":"writ",
			block, rq->nr_sectors, (unsigned long) rq->buffer);
#endif
		OUT_BYTE(block,io_base+IDE_SECTOR_OFFSET);
		OUT_BYTE(block>>=8,io_base+IDE_LCYL_OFFSET);
		OUT_BYTE(block>>=8,io_base+IDE_HCYL_OFFSET);
		OUT_BYTE(((block>>8)&0x0f)|drive->select.all,io_base+IDE_SELECT_OFFSET);
	} else {
		unsigned int sect,head,cyl,track;
		track = block / drive->sect;
		sect  = block % drive->sect + 1;
		OUT_BYTE(sect,io_base+IDE_SECTOR_OFFSET);
		head  = track % drive->head;
		cyl   = track / drive->head;
		OUT_BYTE(cyl,io_base+IDE_LCYL_OFFSET);
		OUT_BYTE(cyl>>8,io_base+IDE_HCYL_OFFSET);
		OUT_BYTE(head|drive->select.all,io_base+IDE_SELECT_OFFSET);
#ifdef DEBUG
		printk("%s: %sing: CHS=%d/%d/%d, sectors=%ld, buffer=0x%08lx\n",
			drive->name, (rq->cmd==READ)?"read":"writ", cyl,
			head, sect, rq->nr_sectors, (unsigned long) rq->buffer);
#endif
	}
#ifdef CONFIG_BLK_DEV_PROMISE
	if (use_promise_io) {
		do_promise_io (drive, rq);
		return;
	}
#endif /* CONFIG_BLK_DEV_PROMISE */
	if (rq->cmd == READ) {
#ifdef CONFIG_BLK_DEV_TRITON
		if (drive->using_dma && !(HWIF(drive)->dmaproc(ide_dma_read, drive)))
			return;
#endif /* CONFIG_BLK_DEV_TRITON */
		ide_set_handler(drive, &read_intr, WAIT_CMD);
		OUT_BYTE(drive->mult_count ? WIN_MULTREAD : WIN_READ, io_base+IDE_COMMAND_OFFSET);
		return;
	}
	if (rq->cmd == WRITE) {
#ifdef CONFIG_BLK_DEV_TRITON
		if (drive->using_dma && !(HWIF(drive)->dmaproc(ide_dma_write, drive)))
			return;
#endif /* CONFIG_BLK_DEV_TRITON */
		OUT_BYTE(drive->mult_count ? WIN_MULTWRITE : WIN_WRITE, io_base+IDE_COMMAND_OFFSET);
		if (ide_wait_stat(drive, DATA_READY, drive->bad_wstat, WAIT_DRQ)) {
			printk("%s: no DRQ after issuing %s\n", drive->name,
				drive->mult_count ? "MULTWRITE" : "WRITE");
			return;
		}
		if (!drive->unmask)
			cli();
		if (drive->mult_count) {
			HWGROUP(drive)->wrq = *rq; /* scratchpad */
			ide_set_handler (drive, &multwrite_intr, WAIT_CMD);
			ide_multwrite(drive, drive->mult_count);
		} else {
			ide_set_handler (drive, &write_intr, WAIT_CMD);
			ide_output_data(drive, rq->buffer, SECTOR_WORDS);
		}
		return;
	}
	printk("%s: bad command: %d\n", drive->name, rq->cmd);
	ide_end_request(0, HWGROUP(drive));
}

/*
 * execute_drive_cmd() issues a special drive command,
 * usually initiated by ioctl() from the external hdparm program.
 */
static void execute_drive_cmd (ide_drive_t *drive, struct request *rq)
{
	byte *args = rq->buffer;
	if (args) {
#ifdef DEBUG
		printk("%s: DRIVE_CMD cmd=0x%02x sc=0x%02x fr=0x%02x xx=0x%02x\n",
		 drive->name, args[0], args[1], args[2], args[3]);
#endif
		OUT_BYTE(args[2],IDE_FEATURE_REG);
		ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
		return;
	} else {
		/*
		 * NULL is actually a valid way of waiting for
		 * all current requests to be flushed from the queue.
		 */
#ifdef DEBUG
		printk("%s: DRIVE_CMD (null)\n", drive->name);
#endif
		ide_end_drive_cmd(drive, GET_STAT(), GET_ERR());
		return;
	}
}

/*
 * do_request() initiates handling of a new I/O request
 */
static inline void do_request (ide_hwif_t *hwif, struct request *rq)
{
	unsigned int minor, unit;
	unsigned long block, blockend;
	ide_drive_t *drive;

	sti();
#ifdef DEBUG
	printk("%s: do_request: current=0x%08lx\n", hwif->name, (unsigned long) rq);
#endif
	minor = MINOR(rq->rq_dev);
	unit = minor >> PARTN_BITS;
	if (MAJOR(rq->rq_dev) != hwif->major || unit >= MAX_DRIVES) {
		printk("%s: bad device number: %s\n",
		       hwif->name, kdevname(rq->rq_dev));
		goto kill_rq;
	}
	drive = &hwif->drives[unit];
#ifdef DEBUG
	if (rq->bh && !buffer_locked(rq->bh)) {
		printk("%s: block not locked\n", drive->name);
		goto kill_rq;
	}
#endif
	block    = rq->sector;
	blockend = block + rq->nr_sectors;
	if ((blockend < block) || (blockend > drive->part[minor&PARTN_MASK].nr_sects)) {
#ifdef MACH
	  printk ("%s%c: bad access: block=%ld, count=%ld, blockend=%ld, nr_sects%ld\n",
		  drive->name, (minor&PARTN_MASK)?'0'+(minor&PARTN_MASK):' ',
		  block, rq->nr_sectors, blockend, drive->part[minor&PARTN_MASK].nr_sects);
#else
		printk("%s%c: bad access: block=%ld, count=%ld\n", drive->name,
		 (minor&PARTN_MASK)?'0'+(minor&PARTN_MASK):' ', block, rq->nr_sectors);
#endif
		goto kill_rq;
	}
	block += drive->part[minor&PARTN_MASK].start_sect + drive->sect0;
#if FAKE_FDISK_FOR_EZDRIVE
	if (block == 0 && drive->remap_0_to_1)
		block = 1;  /* redirect MBR access to EZ-Drive partn table */
#endif /* FAKE_FDISK_FOR_EZDRIVE */
	((ide_hwgroup_t *)hwif->hwgroup)->drive = drive;
#if (DISK_RECOVERY_TIME > 0)
	while ((read_timer() - hwif->last_time) < DISK_RECOVERY_TIME);
#endif

#ifdef CONFIG_BLK_DEV_IDETAPE
	POLL_HWIF_TAPE_DRIVE;	/* macro from ide-tape.h */
#endif /* CONFIG_BLK_DEV_IDETAPE */

	SELECT_DRIVE(hwif,drive);
	if (ide_wait_stat(drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
		printk("%s: drive not ready for command\n", drive->name);
		return;
	}

	if (!drive->special.all) {
		if (rq->cmd == IDE_DRIVE_CMD) {
			execute_drive_cmd(drive, rq);
			return;
		}
#ifdef CONFIG_BLK_DEV_IDEATAPI
		switch (drive->media) {
			case ide_disk:
				do_rw_disk (drive, rq, block);
				return;
#ifdef CONFIG_BLK_DEV_IDECD
			case ide_cdrom:
				ide_do_rw_cdrom (drive, block);
				return;
#endif /* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDETAPE
			case ide_tape:
				idetape_do_request (drive, rq, block);
				return;
#endif /* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
			case ide_floppy:
				idefloppy_do_request (drive, rq, block);
				return;
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
#ifdef CONFIG_BLK_DEV_IDESCSI
			case ide_scsi:
				idescsi_do_request (drive, rq, block);
				return;
#endif /* CONFIG_BLK_DEV_IDESCSI */

			default:
				printk("%s: media type %d not supported\n",
					drive->name, drive->media);
				goto kill_rq;
		}
#else
		do_rw_disk (drive, rq, block); /* simpler and faster */
		return;
#endif /* CONFIG_BLK_DEV_IDEATAPI */
	}
	do_special(drive);
	return;
kill_rq:
	ide_end_request(0, hwif->hwgroup);
}

/*
 * The driver enables interrupts as much as possible.  In order to do this,
 * (a) the device-interrupt is always masked before entry, and
 * (b) the timeout-interrupt is always disabled before entry.
 *
 * If we enter here from, say irq14, and then start a new request for irq15,
 * (possible with "serialize" option) then we cannot ensure that we exit
 * before the irq15 hits us. So, we must be careful not to let this bother us.
 *
 * Interrupts are still masked (by default) whenever we are exchanging
 * data/cmds with a drive, because some drives seem to have very poor
 * tolerance for latency during I/O.  For devices which don't suffer from
 * this problem (most don't), the unmask flag can be set using the "hdparm"
 * utility, to permit other interrupts during data/cmd transfers.
 */
void ide_do_request (ide_hwgroup_t *hwgroup)
{
	cli();	/* paranoia */
	if (hwgroup->handler != NULL) {
		printk("%s: EEeekk!! handler not NULL in ide_do_request()\n", hwgroup->hwif->name);
		return;
	}
	do {
		ide_hwif_t *hwif = hwgroup->hwif;
		struct request *rq;
		if ((rq = hwgroup->rq) == NULL) {
			if (hwif->sharing_irq && hwgroup->drive) /* set nIEN */
				OUT_BYTE(hwgroup->drive->ctl|2,hwif->ctl_port);
			/*
			 * hwgroup->next_hwif is different from hwgroup->hwif
			 * only when a request is inserted using "ide_next".
			 * This saves wear and tear on IDE tapes.
			 */
			hwif = hwgroup->next_hwif;
			do {
				rq = blk_dev[hwif->major].current_request;
				if (rq != NULL && rq->rq_status != RQ_INACTIVE)
					goto got_rq;
			} while ((hwif = hwif->next) != hwgroup->next_hwif);
			hwgroup->active = 0;
			return;		/* no work left for this hwgroup */
		}
	got_rq:
		do_request(hwgroup->hwif = hwgroup->next_hwif = hwif, hwgroup->rq = rq);
		cli();
	} while (hwgroup->handler == NULL);
}

/*
 * do_hwgroup_request() invokes ide_do_request() after first masking
 * all possible interrupts for the current hwgroup.  This prevents race
 * conditions in the event that an unexpected interrupt occurs while
 * we are in the driver.
 *
 * Note that when an interrupt is used to reenter the driver, the first level
 * handler will already have masked the irq that triggered, but any other ones
 * for the hwgroup will still be unmasked.  The driver tries to be careful
 * about such things.
 */
static void do_hwgroup_request (ide_hwgroup_t *hwgroup)
{
	if (hwgroup->handler == NULL) {
		ide_hwif_t *hgif = hwgroup->hwif;
		ide_hwif_t *hwif = hgif;
		hwgroup->active = 1;
		do {
			disable_irq(hwif->irq);
		} while ((hwif = hwif->next) != hgif);
		ide_do_request (hwgroup);
		do {
			enable_irq(hwif->irq);
		} while ((hwif = hwif->next) != hgif);
	}
}

static void do_ide0_request (void)	/* invoked with cli() */
{
	do_hwgroup_request (ide_hwifs[0].hwgroup);
}

#if MAX_HWIFS > 1
static void do_ide1_request (void)	/* invoked with cli() */
{
	do_hwgroup_request (ide_hwifs[1].hwgroup);
}
#endif

#if MAX_HWIFS > 2
static void do_ide2_request (void)	/* invoked with cli() */
{
	do_hwgroup_request (ide_hwifs[2].hwgroup);
}
#endif

#if MAX_HWIFS > 3
static void do_ide3_request (void)	/* invoked with cli() */
{
	do_hwgroup_request (ide_hwifs[3].hwgroup);
}
#endif

static void timer_expiry (unsigned long data)
{
	ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
	ide_drive_t   *drive   = hwgroup->drive;
	unsigned long flags;

	save_flags(flags);
	cli();

	if (hwgroup->poll_timeout != 0) { /* polling in progress? */
		ide_handler_t *handler = hwgroup->handler;
		hwgroup->handler = NULL;
		handler(drive);
	} else if (hwgroup->handler == NULL) {	 /* not waiting for anything? */
		sti(); /* drive must have responded just as the timer expired */
		printk("%s: marginal timeout\n", drive->name);
	} else {
		hwgroup->handler = NULL;	/* abort the operation */
		if (hwgroup->hwif->dmaproc)
			(void) hwgroup->hwif->dmaproc (ide_dma_abort, drive);
		ide_error(drive, "irq timeout", GET_STAT());
	}
	if (hwgroup->handler == NULL)
		do_hwgroup_request (hwgroup);
	restore_flags(flags);
}

/*
 * There's nothing really useful we can do with an unexpected interrupt,
 * other than reading the status register (to clear it), and logging it.
 * There should be no way that an irq can happen before we're ready for it,
 * so we needn't worry much about losing an "important" interrupt here.
 *
 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
 * drive enters "idle", "standby", or "sleep" mode, so if the status looks
 * "good", we just ignore the interrupt completely.
 *
 * This routine assumes cli() is in effect when called.
 *
 * If an unexpected interrupt happens on irq15 while we are handling irq14
 * and if the two interfaces are "serialized" (CMD640), then it looks like
 * we could screw up by interfering with a new request being set up for irq15.
 *
 * In reality, this is a non-issue.  The new command is not sent unless the
 * drive is ready to accept one, in which case we know the drive is not
 * trying to interrupt us.  And ide_set_handler() is always invoked before
 * completing the issuance of any new drive command, so we will not be
 * accidently invoked as a result of any valid command completion interrupt.
 *
 */
static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
{
	byte stat;
	unsigned int unit;
	ide_hwif_t *hwif = hwgroup->hwif;

	/*
	 * handle the unexpected interrupt
	 */
	do {
		if (hwif->irq == irq) {
			for (unit = 0; unit < MAX_DRIVES; ++unit) {
				ide_drive_t *drive = &hwif->drives[unit];
				if (!drive->present)
					continue;
				SELECT_DRIVE(hwif,drive);
				udelay(100);  /* Ugly, but wait_stat() may not be safe here */
				if (!OK_STAT(stat=GET_STAT(), drive->ready_stat, BAD_STAT)) {
					/* Try to not flood the console with msgs */
					static unsigned long last_msgtime = 0;
					if ((last_msgtime + (HZ/2)) < jiffies) {
						last_msgtime = jiffies;
						(void) ide_dump_status(drive, "unexpected_intr", stat);
					}
				}
				if ((stat & DRQ_STAT))
					try_to_flush_leftover_data(drive);
			}
		}
	} while ((hwif = hwif->next) != hwgroup->hwif);
	SELECT_DRIVE(hwif,hwgroup->drive); /* Ugh.. probably interrupts current I/O */
	udelay(100);  /* Ugly, but wait_stat() may not be safe here */
}

/*
 * entry point for all interrupts, caller does cli() for us
 */
void ide_intr (int irq, void *dev_id, struct pt_regs *regs)
{
	ide_hwgroup_t *hwgroup = dev_id;
	ide_handler_t *handler;

	if (irq == hwgroup->hwif->irq && (handler = hwgroup->handler) != NULL) {
		ide_drive_t *drive = hwgroup->drive;
		hwgroup->handler = NULL;
		del_timer(&(hwgroup->timer));
		if (drive->unmask)
			sti();
		handler(drive);
		cli();	/* this is necessary, as next rq may be different irq */
		if (hwgroup->handler == NULL) {
			SET_RECOVERY_TIMER(HWIF(drive));
 			ide_do_request(hwgroup);
		}
	} else {
		unexpected_intr(irq, hwgroup);
	}
	cli();
}

/*
 * get_info_ptr() returns the (ide_drive_t *) for a given device number.
 * It returns NULL if the given device number does not match any present drives.
 */
static ide_drive_t *get_info_ptr (kdev_t i_rdev)
{
	int		major = MAJOR(i_rdev);
	unsigned int	h;

	for (h = 0; h < MAX_HWIFS; ++h) {
		ide_hwif_t  *hwif = &ide_hwifs[h];
		if (hwif->present && major == hwif->major) {
			unsigned unit = DEVICE_NR(i_rdev);
			if (unit < MAX_DRIVES) {
				ide_drive_t *drive = &hwif->drives[unit];
				if (drive->present)
					return drive;
			} else if (major == IDE0_MAJOR && unit < 4) {
				printk("ide: probable bad entry for /dev/hd%c\n", 'a'+unit);
				printk("ide: to fix it, run:  /usr/src/linux/scripts/MAKEDEV.ide\n");
			}
			break;
		}
	}
	return NULL;
}

/*
 * This function is intended to be used prior to invoking ide_do_drive_cmd().
 */
void ide_init_drive_cmd (struct request *rq)
{
	rq->buffer = NULL;
	rq->cmd = IDE_DRIVE_CMD;
	rq->sector = 0;
	rq->nr_sectors = 0;
	rq->current_nr_sectors = 0;
	rq->sem = NULL;
	rq->bh = NULL;
	rq->bhtail = NULL;
	rq->next = NULL;

#if 0	/* these are done each time through ide_do_drive_cmd() */
	rq->errors = 0;
	rq->rq_status = RQ_ACTIVE;
	rq->rq_dev = ????;
#endif
}

/*
 * This function issues a special IDE device request
 * onto the request queue.
 *
 * If action is ide_wait, then the rq is queued at the end of the
 * request queue, and the function sleeps until it has been processed.
 * This is for use when invoked from an ioctl handler.
 *
 * If action is ide_preempt, then the rq is queued at the head of
 * the request queue, displacing the currently-being-processed
 * request and this function returns immediately without waiting
 * for the new rq to be completed.  This is VERY DANGEROUS, and is
 * intended for careful use by the ATAPI tape/cdrom driver code.
 *
 * If action is ide_next, then the rq is queued immediately after
 * the currently-being-processed-request (if any), and the function
 * returns without waiting for the new rq to be completed.  As above,
 * This is VERY DANGEROUS, and is intended for careful use by the
 * ATAPI tape/cdrom driver code.
 *
 * If action is ide_end, then the rq is queued at the end of the
 * request queue, and the function returns immediately without waiting
 * for the new rq to be completed. This is again intended for careful
 * use by the ATAPI tape/cdrom driver code. (Currently used by ide-tape.c,
 * when operating in the pipelined operation mode).
 */
int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
{
	unsigned long flags;
	unsigned int major = HWIF(drive)->major;
	struct request *cur_rq;
	struct blk_dev_struct *bdev = &blk_dev[major];
	struct semaphore sem = MUTEX_LOCKED;

	if (IS_PROMISE_DRIVE && rq->buffer != NULL)
		return -ENOSYS;  /* special drive cmds not supported */
	rq->errors = 0;
	rq->rq_status = RQ_ACTIVE;
	rq->rq_dev = MKDEV(major,(drive->select.b.unit)<<PARTN_BITS);
	if (action == ide_wait)
		rq->sem = &sem;
	unplug_device(bdev);

	save_flags(flags);
	cli();
	if (action == ide_next)
		HWGROUP(drive)->next_hwif = HWIF(drive);
	cur_rq = bdev->current_request;

	if (cur_rq == NULL || action == ide_preempt) {
		rq->next = cur_rq;
		bdev->current_request = rq;
		if (action == ide_preempt)
			HWGROUP(drive)->rq = NULL;
	} else {
		if (action == ide_wait || action == ide_end) {
			while (cur_rq->next != NULL)	/* find end of list */
				cur_rq = cur_rq->next;
		}
		rq->next = cur_rq->next;
		cur_rq->next = rq;
	}
	if (!HWGROUP(drive)->active) {
		do_hwgroup_request(HWGROUP(drive));
		cli();
	}
	if (action == ide_wait  && rq->rq_status != RQ_INACTIVE)
		down(&sem);	/* wait for it to be serviced */
	restore_flags(flags);
	return rq->errors ? -EIO : 0;	/* return -EIO if errors */
}

static int ide_open(struct inode * inode, struct file * filp)
{
	ide_drive_t *drive;
	unsigned long flags;

	if ((drive = get_info_ptr(inode->i_rdev)) == NULL)
		return -ENXIO;
	save_flags(flags);
	cli();
	while (drive->busy)
		sleep_on(&drive->wqueue);
	drive->usage++;
	restore_flags(flags);
#ifdef CONFIG_BLK_DEV_IDECD
	if (drive->media == ide_cdrom)
		return ide_cdrom_open (inode, filp, drive);
#endif	/* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDETAPE
	if (drive->media == ide_tape)
		return idetape_blkdev_open (inode, filp, drive);
#endif	/* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
	if (drive->media == ide_floppy)
		return idefloppy_open (inode, filp, drive);
#endif	/* CONFIG_BLK_DEV_IDEFLOPPY */
#ifdef CONFIG_BLK_DEV_IDESCSI
	if (drive->media == ide_scsi)
		return idescsi_open (inode, filp, drive);
#endif	/* CONFIG_BLK_DEV_IDESCSI */
	if (drive->removable && drive->usage == 1) {
		byte door_lock[] = {WIN_DOORLOCK,0,0,0};
		struct request rq;
		check_disk_change(inode->i_rdev);
		ide_init_drive_cmd (&rq);
		rq.buffer = door_lock;
		/*
		 * Ignore the return code from door_lock,
		 * since the open() has already succeeded,
		 * and the door_lock is irrelevant at this point.
		 */
		(void) ide_do_drive_cmd(drive, &rq, ide_wait);
	}
	return 0;
}

/*
 * Releasing a block device means we sync() it, so that it can safely
 * be forgotten about...
 */
static void ide_release(struct inode * inode, struct file * file)
{
	ide_drive_t *drive;

	if ((drive = get_info_ptr(inode->i_rdev)) != NULL) {
		fsync_dev(inode->i_rdev);
		drive->usage--;
#ifdef CONFIG_BLK_DEV_IDECD
		if (drive->media == ide_cdrom) {
			ide_cdrom_release (inode, file, drive);
			return;
		}
#endif	/* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDETAPE
		if (drive->media == ide_tape) {
			idetape_blkdev_release (inode, file, drive);
			return;
		}
#endif	/* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
		if (drive->media == ide_floppy) {
			idefloppy_release (inode, file, drive);
			return;
		}
#endif	/* CONFIG_BLK_DEV_IDEFLOPPY */
#ifdef CONFIG_BLK_DEV_IDESCSI
		if (drive->media == ide_scsi) {
			idescsi_ide_release (inode, file, drive);
			return;
		}
#endif	/* CONFIG_BLK_DEV_IDESCSI */
		if (drive->removable && !drive->usage) {
			byte door_unlock[] = {WIN_DOORUNLOCK,0,0,0};
			struct request rq;
			invalidate_buffers(inode->i_rdev);
			ide_init_drive_cmd (&rq);
			rq.buffer = door_unlock;
			(void) ide_do_drive_cmd(drive, &rq, ide_wait);
		}
	}
}

/*
 * This routine is called to flush all partitions and partition tables
 * for a changed disk, and then re-read the new partition table.
 * If we are revalidating a disk because of a media change, then we
 * enter with usage == 0.  If we are using an ioctl, we automatically have
 * usage == 1 (we need an open channel to use an ioctl :-), so this
 * is our limit.
 */
static int revalidate_disk(kdev_t i_rdev)
{
	ide_drive_t *drive;
	unsigned int p, major, minor;
	long flags;

	if ((drive = get_info_ptr(i_rdev)) == NULL)
		return -ENODEV;

	major = MAJOR(i_rdev);
	minor = drive->select.b.unit << PARTN_BITS;
	save_flags(flags);
	cli();
	if (drive->busy || (drive->usage > 1)) {
		restore_flags(flags);
		return -EBUSY;
	};
	drive->busy = 1;
	restore_flags(flags);

	for (p = 0; p < (1<<PARTN_BITS); ++p) {
		if (drive->part[p].nr_sects > 0) {
			kdev_t devp = MKDEV(major, minor+p);
			fsync_dev          (devp);
			invalidate_inodes  (devp);
			invalidate_buffers (devp);
			set_blocksize(devp, 1024);
		}
		drive->part[p].start_sect = 0;
		drive->part[p].nr_sects   = 0;
	};

	drive->part[0].nr_sects = current_capacity(drive);
	if ((drive->media != ide_disk && drive->media != ide_floppy) || !drive->part[0].nr_sects)
		drive->part[0].start_sect = -1;
	resetup_one_dev(HWIF(drive)->gd, drive->select.b.unit);

	drive->busy = 0;
	wake_up(&drive->wqueue);
	return 0;
}

static int write_fs_long (unsigned long useraddr, long value)
{
	int err;

	if (NULL == (long *)useraddr)
		return -EINVAL;
	if ((err = verify_area(VERIFY_WRITE, (long *)useraddr, sizeof(long))))
		return err;
	put_user((unsigned)value, (long *) useraddr);
	return 0;
}

static int ide_ioctl (struct inode *inode, struct file *file,
			unsigned int cmd, unsigned long arg)
{
	int err;
	ide_drive_t *drive;
	unsigned long flags;
	struct request rq;

	if (!inode || !(inode->i_rdev))
		return -EINVAL;
	if ((drive = get_info_ptr(inode->i_rdev)) == NULL)
		return -ENODEV;
	ide_init_drive_cmd (&rq);
	switch (cmd) {
		case HDIO_GETGEO:
		{
			struct hd_geometry *loc = (struct hd_geometry *) arg;
			if (!loc || (drive->media != ide_disk && drive->media != ide_floppy)) return -EINVAL;
#ifdef MACH
			loc->heads = drive->bios_head;
			loc->sectors = drive->bios_sect;
			loc->cylinders = drive->bios_cyl;
			loc->start
			  = (drive->part[MINOR(inode->i_rdev)&PARTN_MASK]
			     .start_sect);
#else
			err = verify_area(VERIFY_WRITE, loc, sizeof(*loc));
			if (err) return err;
			put_user(drive->bios_head, (byte *) &loc->heads);
			put_user(drive->bios_sect, (byte *) &loc->sectors);
			put_user(drive->bios_cyl, (unsigned short *) &loc->cylinders);
			put_user((unsigned)drive->part[MINOR(inode->i_rdev)&PARTN_MASK].start_sect,
				(unsigned long *) &loc->start);
#endif
			return 0;
		}
		case BLKFLSBUF:
			if (!suser()) return -EACCES;
			fsync_dev(inode->i_rdev);
			invalidate_buffers(inode->i_rdev);
			return 0;

		case BLKRASET:
			if (!suser()) return -EACCES;
			if(arg > 0xff) return -EINVAL;
			read_ahead[MAJOR(inode->i_rdev)] = arg;
			return 0;

		case BLKRAGET:
			return write_fs_long(arg, read_ahead[MAJOR(inode->i_rdev)]);

	 	case BLKGETSIZE:   /* Return device size */
			return write_fs_long(arg, drive->part[MINOR(inode->i_rdev)&PARTN_MASK].nr_sects);
		case BLKRRPART: /* Re-read partition tables */
			if (!suser()) return -EACCES;
			return revalidate_disk(inode->i_rdev);

		case HDIO_GET_KEEPSETTINGS:
			return write_fs_long(arg, drive->keep_settings);

		case HDIO_GET_UNMASKINTR:
			return write_fs_long(arg, drive->unmask);

		case HDIO_GET_DMA:
			return write_fs_long(arg, drive->using_dma);

		case HDIO_GET_32BIT:
			return write_fs_long(arg, drive->io_32bit);

		case HDIO_GET_MULTCOUNT:
			return write_fs_long(arg, drive->mult_count);

		case HDIO_GET_IDENTITY:
			if (!arg || (MINOR(inode->i_rdev) & PARTN_MASK))
				return -EINVAL;
			if (drive->id == NULL)
				return -ENOMSG;
			err = verify_area(VERIFY_WRITE, (char *)arg, sizeof(*drive->id));
			if (!err)
				memcpy_tofs((char *)arg, (char *)drive->id, sizeof(*drive->id));
			return err;

			case HDIO_GET_NOWERR:
			return write_fs_long(arg, drive->bad_wstat == BAD_R_STAT);

		case HDIO_SET_DMA:
			if (!suser()) return -EACCES;
#ifdef CONFIG_BLK_DEV_IDECD
			if (drive->media == ide_cdrom)
				return -EPERM;
#endif /* CONFIG_BLK_DEV_IDECD */
			if (!drive->id || !(drive->id->capability & 1) || !HWIF(drive)->dmaproc)
				return -EPERM;
		case HDIO_SET_KEEPSETTINGS:
		case HDIO_SET_UNMASKINTR:
		case HDIO_SET_NOWERR:
			if (arg > 1)
				return -EINVAL;
		case HDIO_SET_32BIT:
			if (!suser()) return -EACCES;
			if ((MINOR(inode->i_rdev) & PARTN_MASK))
				return -EINVAL;
			save_flags(flags);
			cli();
			switch (cmd) {
				case HDIO_SET_DMA:
					if (!(HWIF(drive)->dmaproc)) {
						restore_flags(flags);
						return -EPERM;
					}
					drive->using_dma = arg;
					break;
				case HDIO_SET_KEEPSETTINGS:
					drive->keep_settings = arg;
					break;
				case HDIO_SET_UNMASKINTR:
					if (arg && drive->no_unmask) {
						restore_flags(flags);
						return -EPERM;
					}
					drive->unmask = arg;
					break;
				case HDIO_SET_NOWERR:
					drive->bad_wstat = arg ? BAD_R_STAT : BAD_W_STAT;
					break;
				case HDIO_SET_32BIT:
					if (arg > (1 + (SUPPORT_VLB_SYNC<<1))) {
						restore_flags(flags);
						return -EINVAL;
					}
					if (arg && drive->no_io_32bit) {
						restore_flags(flags);
						return -EPERM;
					}
					drive->io_32bit = arg;
#ifdef CONFIG_BLK_DEV_DTC2278
					if (HWIF(drive)->chipset == ide_dtc2278)
						HWIF(drive)->drives[!drive->select.b.unit].io_32bit = arg;
#endif /* CONFIG_BLK_DEV_DTC2278 */
					break;
			}
			restore_flags(flags);
			return 0;

		case HDIO_SET_MULTCOUNT:
			if (!suser()) return -EACCES;
			if (MINOR(inode->i_rdev) & PARTN_MASK)
				return -EINVAL;
			if (drive->id && arg > drive->id->max_multsect)
				return -EINVAL;
			save_flags(flags);
			cli();
			if (drive->special.b.set_multmode) {
				restore_flags(flags);
				return -EBUSY;
			}
			drive->mult_req = arg;
			drive->special.b.set_multmode = 1;
			restore_flags(flags);
			(void) ide_do_drive_cmd (drive, &rq, ide_wait);
			return (drive->mult_count == arg) ? 0 : -EIO;

		case HDIO_DRIVE_CMD:
		{
			byte args[4], *argbuf = args;
			int argsize = 4;
			if (!suser() || securelevel > 0) return -EACCES;
			if (NULL == (void *) arg) {
				err = ide_do_drive_cmd(drive, &rq, ide_wait);
			} else if (!(err = verify_area(VERIFY_READ,(void *)arg, 4))) {
				memcpy_fromfs(args, (void *)arg, 4);
				if (args[3]) {
					argsize = 4 + (SECTOR_WORDS * 4 * args[3]);
					argbuf = kmalloc(argsize, GFP_KERNEL);
					if (argbuf == NULL)
						return -ENOMEM;
					argbuf[0] = args[0];
					argbuf[1] = args[1];
					argbuf[2] = args[2];
					argbuf[3] = args[3];
				}
				if (!(err = verify_area(VERIFY_WRITE,(void *)arg, argsize))) {
					rq.buffer = argbuf;
					err = ide_do_drive_cmd(drive, &rq, ide_wait);
					memcpy_tofs((void *)arg, argbuf, argsize);
				}
				if (argsize > 4)
					kfree(argbuf);
			}
			return err;
		}
		case HDIO_SET_PIO_MODE:
			if (!suser()) return -EACCES;
			if (MINOR(inode->i_rdev) & PARTN_MASK)
				return -EINVAL;
			if (!HWIF(drive)->tuneproc)
				return -ENOSYS;
			save_flags(flags);
			cli();
			if (drive->special.b.set_tune) {
				restore_flags(flags);
				return -EBUSY;
			}
			drive->tune_req = (byte) arg;
			drive->special.b.set_tune = 1;
			restore_flags(flags);
			(void) ide_do_drive_cmd (drive, &rq, ide_wait);
			return 0;

		RO_IOCTLS(inode->i_rdev, arg);

		default:
#ifdef CONFIG_BLK_DEV_IDECD
			if (drive->media == ide_cdrom)
				return ide_cdrom_ioctl(drive, inode, file, cmd, arg);
#endif /* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDETAPE
			if (drive->media == ide_tape)
				return idetape_blkdev_ioctl(drive, inode, file, cmd, arg);
#endif /* CONFIG_BLK_DEV_IDETAPE */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
			if (drive->media == ide_floppy)
				return idefloppy_ioctl(drive, inode, file, cmd, arg);
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
#ifdef CONFIG_BLK_DEV_IDESCSI
			if (drive->media == ide_scsi)
				return idescsi_ioctl(drive, inode, file, cmd, arg);
#endif /* CONFIG_BLK_DEV_IDESCSI */
			return -EPERM;
	}
}

static int ide_check_media_change (kdev_t i_rdev)
{
	ide_drive_t *drive;

	if ((drive = get_info_ptr(i_rdev)) == NULL)
		return -ENODEV;
#ifdef CONFIG_BLK_DEV_IDECD
	if (drive->media == ide_cdrom)
		return ide_cdrom_check_media_change (drive);
#endif	/* CONFIG_BLK_DEV_IDECD */
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
	if (drive->media == ide_floppy)
		return idefloppy_media_change (drive);
#endif	/* CONFIG_BLK_DEV_IDEFLOPPY */
	if (drive->removable) /* for disks */
		return 1;	/* always assume it was changed */
	return 0;
}

void ide_fixstring (byte *s, const int bytecount, const int byteswap)
{
	byte *p = s, *end = &s[bytecount & ~1]; /* bytecount must be even */

	if (byteswap) {
		/* convert from big-endian to host byte order */
		for (p = end ; p != s;) {
			unsigned short *pp = (unsigned short *) (p -= 2);
			*pp = ntohs(*pp);
		}
	}

	/* strip leading blanks */
	while (s != end && *s == ' ')
		++s;

	/* compress internal blanks and strip trailing blanks */
	while (s != end && *s) {
		if (*s++ != ' ' || (s != end && *s && *s != ' '))
			*p++ = *(s-1);
	}

	/* wipe out trailing garbage */
	while (p != end)
		*p++ = '\0';
}

static inline void do_identify (ide_drive_t *drive, byte cmd)
{
	int bswap;
	struct hd_driveid *id;
	unsigned long capacity, check;

	id = drive->id = kmalloc (SECTOR_WORDS*4, GFP_KERNEL);
	ide_input_data(drive, id, SECTOR_WORDS);/* read 512 bytes of id info */
	sti();

#if defined (CONFIG_SCSI_EATA_DMA) || defined (CONFIG_SCSI_EATA_PIO) || defined (CONFIG_SCSI_EATA)
	/*
	 * EATA SCSI controllers do a hardware ATA emulation:
	 * Ignore them if there is a driver for them available.
	 */
	if ((id->model[0] == 'P' && id->model[1] == 'M')
	 || (id->model[0] == 'S' && id->model[1] == 'K')) {
		printk("%s: EATA SCSI HBA %.10s\n", drive->name, id->model);
		drive->present = 0;
		return;
	}
#endif

	/*
	 *  WIN_IDENTIFY returns little-endian info,
	 *  WIN_PIDENTIFY *usually* returns little-endian info.
	 */
	bswap = 1;
	if (cmd == WIN_PIDENTIFY) {
		if ((id->model[0] == 'N' && id->model[1] == 'E') /* NEC */
		 || (id->model[0] == 'F' && id->model[1] == 'X') /* Mitsumi */
		 || (id->model[0] == 'P' && id->model[1] == 'i'))/* Pioneer */
			bswap = 0;	/* Vertos drives may still be weird */
	}
	ide_fixstring (id->model,     sizeof(id->model),     bswap);
	ide_fixstring (id->fw_rev,    sizeof(id->fw_rev),    bswap);
	ide_fixstring (id->serial_no, sizeof(id->serial_no), bswap);

	if (strstr(id->model, "E X A B Y T E N E S T"))
		return;

#ifdef CONFIG_BLK_DEV_IDEATAPI
	/*
	 * Check for an ATAPI device
	 */
	if (cmd == WIN_PIDENTIFY) {
		byte type = (id->config >> 8) & 0x1f;
		printk("%s: %s, ATAPI ", drive->name, id->model);
#ifdef CONFIG_BLK_DEV_PROMISE
		if (HWIF(drive)->is_promise2) {
			printk(" -- not supported on 2nd Promise port\n");
			drive->present = 0;
			return;
		}
#endif /* CONFIG_BLK_DEV_PROMISE */
		if (!drive->ide_scsi) switch (type) {
			case 0:
				if (!strstr(id->model, "oppy") && !strstr(id->model, "poyp") && !strstr(id->model, "ZIP"))
					printk("cdrom or floppy?, assuming ");
				if (drive->media != ide_cdrom && !strstr(id->model, "CD-ROM")) {
#ifdef CONFIG_BLK_DEV_IDEFLOPPY
					printk("FLOPPY drive\n");
					drive->media = ide_floppy;
					if (idefloppy_identify_device(drive, id))
						drive->present = 1;
					return;
#else
					printk("FLOPPY ");
					break;
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
				}
				/* Early cdrom models used zero */
			case 5:
#ifdef CONFIG_BLK_DEV_IDECD
				printk ("CDROM drive\n");
				drive->media = ide_cdrom;
 				drive->present = 1;
				drive->removable = 1;
				return;
#else
				printk ("CDROM ");
				break;
#endif /* CONFIG_BLK_DEV_IDECD */
			case 1:
#ifdef CONFIG_BLK_DEV_IDETAPE
				printk ("TAPE drive");
				if (idetape_identify_device (drive,id)) {
					drive->media = ide_tape;
					drive->present = 1;
					drive->removable = 1;
					if (drive->autotune != 2 && HWIF(drive)->dmaproc != NULL) {
						if (!HWIF(drive)->dmaproc(ide_dma_check, drive))
							printk(", DMA");
					}
					printk("\n");
				}
				else {
					drive->present = 0;
					printk ("\nide-tape: the tape is not supported by this version of the driver\n");
				}
				return;
#else
				printk ("TAPE ");
				break;
#endif /* CONFIG_BLK_DEV_IDETAPE */
			default:
				drive->present = 0;
				printk("Type %d - Unknown device\n", type);
				return;
		}
#ifdef CONFIG_BLK_DEV_IDESCSI
		printk("drive - enabling SCSI emulation\n");
		drive->media = ide_scsi;
		drive->present = 1;
		idescsi_setup(drive);
#else
		drive->present = 0;
		printk("- not supported by this kernel\n");
#endif /* CONFIG_BLK_DEV_IDESCSI */
		return;
	}
#endif /* CONFIG_BLK_DEV_IDEATAPI */

	/* check for removable disks (eg. SYQUEST), ignore 'WD' drives */
	if (id->config & (1<<7)) {	/* removable disk ? */
		if (id->model[0] != 'W' || id->model[1] != 'D')
			drive->removable = 1;
	}

	/* SunDisk drives: treat as non-removable, force one unit */
	if (id->model[0] == 'S' && id->model[1] == 'u') {
		drive->removable = 0;
		if (drive->select.all & (1<<4)) {
		    drive->present = 0;
		    return;
		}
	}

	drive->media = ide_disk;
	/* Extract geometry if we did not already have one for the drive */
	if (!drive->present) {
		drive->present = 1;
		drive->cyl     = drive->bios_cyl  = id->cyls;
		drive->head    = drive->bios_head = id->heads;
		drive->sect    = drive->bios_sect = id->sectors;
	}
	/* Handle logical geometry translation by the drive */
	if ((id->field_valid & 1) && id->cur_cyls && id->cur_heads
	 && (id->cur_heads <= 16) && id->cur_sectors)
	{
		/*
		 * Extract the physical drive geometry for our use.
		 * Note that we purposely do *not* update the bios info.
		 * This way, programs that use it (like fdisk) will
		 * still have the same logical view as the BIOS does,
		 * which keeps the partition table from being screwed.
		 *
		 * An exception to this is the cylinder count,
		 * which we reexamine later on to correct for 1024 limitations.
		 */
		drive->cyl  = id->cur_cyls;
		drive->head = id->cur_heads;
		drive->sect = id->cur_sectors;

		/* check for word-swapped "capacity" field in id information */
		capacity = drive->cyl * drive->head * drive->sect;
		check = (id->cur_capacity0 << 16) | id->cur_capacity1;
		if (check == capacity) {	/* was it swapped? */
			/* yes, bring it into little-endian order: */
			id->cur_capacity0 = (capacity >>  0) & 0xffff;
			id->cur_capacity1 = (capacity >> 16) & 0xffff;
		}
	}
	/* Use physical geometry if what we have still makes no sense */
	if ((!drive->head || drive->head > 16) && id->heads && id->heads <= 16) {
		drive->cyl  = id->cyls;
		drive->head = id->heads;
		drive->sect = id->sectors;
	}

	/* calculate drive capacity, and select LBA if possible */
	capacity = current_capacity (drive);

	/* Correct the number of cyls if the bios value is too small */
        if (!drive->forced_geom &&
            capacity > drive->bios_cyl * drive->bios_sect * drive->bios_head) {
                unsigned long cylsize;
                cylsize = drive->bios_sect * drive->bios_head;
                if (cylsize == 0 || capacity/cylsize > 65535) {
                        drive->bios_sect = 63;
                        drive->bios_head = 255;
                        cylsize = 63*255;
                }
                if (capacity/cylsize > 65535)
                        drive->bios_cyl = 65535;
                else
                        drive->bios_cyl = capacity/cylsize;
        }

	if (!strncmp(id->model, "BMI ", 4) &&
	    strstr(id->model, " ENHANCED IDE ") &&
	    drive->select.b.lba)
		drive->no_geom = 1;

	printk ("%s: %.40s, %ldMB w/%dkB Cache, CHS=%d/%d/%d",
	 drive->name, id->model, current_capacity(drive)/2048L, id->buf_size/2,
	 drive->bios_cyl, drive->bios_head, drive->bios_sect);

	drive->mult_count = 0;
	if (id->max_multsect) {
		drive->mult_req = INITIAL_MULT_COUNT;
		if (drive->mult_req > id->max_multsect)
			drive->mult_req = id->max_multsect;
		if (drive->mult_req || ((id->multsect_valid & 1) && id->multsect))
			drive->special.b.set_multmode = 1;
	}
	if (drive->autotune != 2 && HWIF(drive)->dmaproc != NULL) {
		if (!(HWIF(drive)->dmaproc(ide_dma_check, drive))) {
			if ((id->field_valid & 4) && (id->dma_ultra & (id->dma_ultra >> 8) & 7))
				printk(", UDMA");
			else
				printk(", DMA");
		}
	}
	printk("\n");
}

/*
 * Delay for *at least* 50ms.  As we don't know how much time is left
 * until the next tick occurs, we wait an extra tick to be safe.
 * This is used only during the probing/polling for drives at boot time.
 */
static void delay_50ms (void)
{
	unsigned long timer = jiffies + ((HZ + 19)/20) + 1;
	while (timer > jiffies);
}

/*
 * try_to_identify() sends an ATA(PI) IDENTIFY request to a drive
 * and waits for a response.  It also monitors irqs while this is
 * happening, in hope of automatically determining which one is
 * being used by the interface.
 *
 * Returns:	0  device was identified
 *		1  device timed-out (no response to identify request)
 *		2  device aborted the command (refused to identify itself)
 */
static int try_to_identify (ide_drive_t *drive, byte cmd)
{
	int hd_status, rc;
	unsigned long timeout;
	unsigned long irqs_on = 0;
	int irq_off;

	if (!HWIF(drive)->irq) {		/* already got an IRQ? */
		probe_irq_off(probe_irq_on());	/* clear dangling irqs */
		irqs_on = probe_irq_on();	/* start monitoring irqs */
		OUT_BYTE(drive->ctl,IDE_CONTROL_REG);	/* enable device irq */
	}

	delay_50ms();				/* take a deep breath */
	if ((IN_BYTE(IDE_ALTSTATUS_REG) ^ IN_BYTE(IDE_STATUS_REG)) & ~INDEX_STAT) {
		printk("%s: probing with STATUS instead of ALTSTATUS\n", drive->name);
		hd_status = IDE_STATUS_REG;	/* ancient Seagate drives */
	} else
		hd_status = IDE_ALTSTATUS_REG;	/* use non-intrusive polling */

#if CONFIG_BLK_DEV_PROMISE
	if (IS_PROMISE_DRIVE) {
		if (promise_cmd(drive,PROMISE_IDENTIFY)) {
			if (irqs_on)
				(void) probe_irq_off(irqs_on);
			return 1;
		}
	} else
#endif /* CONFIG_BLK_DEV_PROMISE */
		OUT_BYTE(cmd,IDE_COMMAND_REG);		/* ask drive for ID */
	timeout = ((cmd == WIN_IDENTIFY) ? WAIT_WORSTCASE : WAIT_PIDENTIFY) / 2;
	timeout += jiffies;
	do {
		if (jiffies > timeout) {
			if (irqs_on)
				(void) probe_irq_off(irqs_on);
			return 1;	/* drive timed-out */
		}
		delay_50ms();		/* give drive a breather */
	} while (IN_BYTE(hd_status) & BUSY_STAT);

	delay_50ms();		/* wait for IRQ and DRQ_STAT */
	if (OK_STAT(GET_STAT(),DRQ_STAT,BAD_R_STAT)) {
		unsigned long flags;
		save_flags(flags);
		cli();			/* some systems need this */
		do_identify(drive, cmd); /* drive returned ID */
		rc = 0;			/* drive responded with ID */
		(void) GET_STAT();	/* clear drive IRQ */
		restore_flags(flags);
	} else
		rc = 2;			/* drive refused ID */
	if (!HWIF(drive)->irq) {
		irq_off = probe_irq_off(irqs_on);	/* get our irq number */
		if (irq_off > 0) {
			HWIF(drive)->irq = irq_off; /* save it for later */
			irqs_on = probe_irq_on();
			OUT_BYTE(drive->ctl|2,IDE_CONTROL_REG); /* mask device irq */
			udelay(5);
			(void) probe_irq_off(irqs_on);
			(void) probe_irq_off(probe_irq_on()); /* clear self-inflicted irq */
			(void) GET_STAT();	/* clear drive IRQ */

		} else {	/* Mmmm.. multiple IRQs.. don't know which was ours */
			printk("%s: IRQ probe failed (%d)\n", drive->name, irq_off);
#ifdef CONFIG_BLK_DEV_CMD640
#ifdef CMD640_DUMP_REGS
			if (HWIF(drive)->chipset == ide_cmd640) {
				printk("%s: Hmmm.. probably a driver problem.\n", drive->name);
				CMD640_DUMP_REGS;
			}
#endif /* CMD640_DUMP_REGS */
#endif /* CONFIG_BLK_DEV_CMD640 */
		}
	}
	return rc;
}

/*
 * do_probe() has the difficult job of finding a drive if it exists,
 * without getting hung up if it doesn't exist, without trampling on
 * ethernet cards, and without leaving any IRQs dangling to haunt us later.
 *
 * If a drive is "known" to exist (from CMOS or kernel parameters),
 * but does not respond right away, the probe will "hang in there"
 * for the maximum wait time (about 30 seconds), otherwise it will
 * exit much more quickly.
 *
 * Returns:	0  device was identified
 *		1  device timed-out (no response to identify request)
 *		2  device aborted the command (refused to identify itself)
 *		3  bad status from device (possible for ATAPI drives)
 *		4  probe was not attempted because failure was obvious
 */
static int do_probe (ide_drive_t *drive, byte cmd)
{
	int rc;
	ide_hwif_t *hwif = HWIF(drive);
	unsigned long timeout;
#ifdef CONFIG_BLK_DEV_IDEATAPI
	if (drive->present) {	/* avoid waiting for inappropriate probes */
		if ((drive->media != ide_disk) && (cmd == WIN_IDENTIFY))
			return 4;
	}
#endif	/* CONFIG_BLK_DEV_IDEATAPI */
#ifdef DEBUG
	printk("probing for %s: present=%d, media=%d, probetype=%s\n",
		drive->name, drive->present, drive->media,
		(cmd == WIN_IDENTIFY) ? "ATA" : "ATAPI");
#endif
	SELECT_DRIVE(hwif,drive);
	delay_50ms();
	if (IN_BYTE(IDE_SELECT_REG) != drive->select.all && !drive->present) {
		OUT_BYTE(0xa0,IDE_SELECT_REG);	/* exit with drive0 selected */
		delay_50ms();		/* allow BUSY_STAT to assert & clear */
		return 3;    /* no i/f present: avoid killing ethernet cards */
	}

	if (OK_STAT(GET_STAT(),READY_STAT,BUSY_STAT)
	 || drive->present || cmd == WIN_PIDENTIFY)
	{
		if ((rc = try_to_identify(drive,cmd)))   /* send cmd and wait */
			rc = try_to_identify(drive,cmd); /* failed: try again */
		if (rc == 1 && cmd == WIN_PIDENTIFY && drive->autotune != 2) {
			printk("%s: no response (status = 0x%02x), resetting drive\n", drive->name, GET_STAT());
			delay_50ms();
			OUT_BYTE (drive->select.all, IDE_SELECT_REG);
			delay_50ms();
			OUT_BYTE(WIN_SRST, IDE_COMMAND_REG);
			timeout = jiffies;
			while ((GET_STAT() & BUSY_STAT) && jiffies < timeout + WAIT_WORSTCASE)
				delay_50ms();
			rc = try_to_identify(drive, cmd);
		}
		if (rc == 1)
			printk("%s: no response (status = 0x%02x)\n", drive->name, GET_STAT());
		(void) GET_STAT();		/* ensure drive irq is clear */
	} else {
		rc = 3;				/* not present or maybe ATAPI */
	}
	if (drive->select.b.unit != 0) {
		OUT_BYTE(0xa0,IDE_SELECT_REG);	/* exit with drive0 selected */
		delay_50ms();
		(void) GET_STAT();		/* ensure drive irq is clear */
	}
	return rc;
}

static void enable_nest (ide_drive_t *drive)
{
	unsigned long timeout;

	printk("%s: enabling %s -- ", HWIF(drive)->name, drive->id->model);
	SELECT_DRIVE(HWIF(drive), drive);
	delay_50ms();
	OUT_BYTE(EXABYTE_ENABLE_NEST, IDE_COMMAND_REG);
	timeout = jiffies + WAIT_WORSTCASE;
	do {
		if (jiffies > timeout) {
			printk("failed (timeout)\n");
			return;
		}
		delay_50ms();
	} while (GET_STAT() & BUSY_STAT);
	delay_50ms();
	if (!OK_STAT(GET_STAT(), 0, BAD_STAT))
		printk("failed (status = 0x%02x)\n", GET_STAT());
	else
		printk("success\n");
	if (do_probe(drive, WIN_IDENTIFY) >= 2) { /* if !(success||timed-out) */
#ifdef CONFIG_BLK_DEV_IDEATAPI
		(void) do_probe(drive, WIN_PIDENTIFY); /* look for ATAPI device */
#endif	/* CONFIG_BLK_DEV_IDEATAPI */
	}
}

/*
 * probe_for_drive() tests for existence of a given drive using do_probe().
 *
 * Returns:	0  no device was found
 *		1  device was found (note: drive->present might still be 0)
 */
static inline byte probe_for_drive (ide_drive_t *drive)
{
	if (drive->noprobe)			/* skip probing? */
		return drive->present;
	if (do_probe(drive, WIN_IDENTIFY) >= 2) { /* if !(success||timed-out) */
#ifdef CONFIG_BLK_DEV_IDEATAPI
		(void) do_probe(drive, WIN_PIDENTIFY); /* look for ATAPI device */
#endif	/* CONFIG_BLK_DEV_IDEATAPI */
	}
	if (drive->id && strstr(drive->id->model, "E X A B Y T E N E S T"))
		enable_nest(drive);
	if (!drive->present)
		return 0;			/* drive not found */
	if (drive->id == NULL) {		/* identification failed? */
		if (drive->media == ide_disk) {
			printk ("%s: non-IDE drive, CHS=%d/%d/%d\n",
			 drive->name, drive->cyl, drive->head, drive->sect);
		}
#ifdef CONFIG_BLK_DEV_IDECD
		else if (drive->media == ide_cdrom) {
			printk("%s: ATAPI cdrom (?)\n", drive->name);
		}
#endif	/* CONFIG_BLK_DEV_IDECD */
		else {
			drive->present = 0;	/* nuke it */
		}
	}
	return 1;	/* drive was found */
}

/*
 * We query CMOS about hard disks : it could be that we have a SCSI/ESDI/etc
 * controller that is BIOS compatible with ST-506, and thus showing up in our
 * BIOS table, but not register compatible, and therefore not present in CMOS.
 *
 * Furthermore, we will assume that our ST-506 drives <if any> are the primary
 * drives in the system -- the ones reflected as drive 1 or 2.  The first
 * drive is stored in the high nibble of CMOS byte 0x12, the second in the low
 * nibble.  This will be either a 4 bit drive type or 0xf indicating use byte
 * 0x19 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.  A non-zero value
 * means we have an AT controller hard disk for that drive.
 *
 * Of course, there is no guarantee that either drive is actually on the
 * "primary" IDE interface, but we don't bother trying to sort that out here.
 * If a drive is not actually on the primary interface, then these parameters
 * will be ignored.  This results in the user having to supply the logical
 * drive geometry as a boot parameter for each drive not on the primary i/f.
 *
 * The only "perfect" way to handle this would be to modify the setup.[cS] code
 * to do BIOS calls Int13h/Fn08h and Int13h/Fn48h to get all of the drive info
 * for us during initialization.  I have the necessary docs -- any takers?  -ml
 */
static void probe_cmos_for_drives (ide_hwif_t *hwif)
{
#ifdef __i386__
	extern struct drive_info_struct drive_info;
	byte cmos_disks, *BIOS = (byte *) &drive_info;
	int unit;

#ifdef CONFIG_BLK_DEV_PROMISE
	if (hwif->is_promise2)
		return;
#endif /* CONFIG_BLK_DEV_PROMISE */
	outb_p(0x12,0x70);		/* specify CMOS address 0x12 */
	cmos_disks = inb_p(0x71);	/* read the data from 0x12 */
	/* Extract drive geometry from CMOS+BIOS if not already setup */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
		if ((cmos_disks & (0xf0 >> (unit*4))) && !drive->present && !drive->nobios) {
			drive->cyl   = drive->bios_cyl  = *(unsigned short *)BIOS;
			drive->head  = drive->bios_head = *(BIOS+2);
			drive->sect  = drive->bios_sect = *(BIOS+14);
			drive->ctl   = *(BIOS+8);
			drive->present = 1;
		}
		BIOS += 16;
	}
#endif
}

/*
 * This routine only knows how to look for drive units 0 and 1
 * on an interface, so any setting of MAX_DRIVES > 2 won't work here.
 */
static void probe_hwif (ide_hwif_t *hwif)
{
	unsigned int unit;

	if (hwif->noprobe)
		return;
	if (hwif->io_base == HD_DATA)
		probe_cmos_for_drives (hwif);
#if CONFIG_BLK_DEV_PROMISE
	if (!hwif->is_promise2 &&
	   (check_region(hwif->io_base,8) || check_region(hwif->ctl_port,1))) {
#else
	if (check_region(hwif->io_base,8) || check_region(hwif->ctl_port,1)) {
#endif /* CONFIG_BLK_DEV_PROMISE */
		int msgout = 0;
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			if (drive->present) {
				drive->present = 0;
				printk("%s: ERROR, PORTS ALREADY IN USE\n", drive->name);
				msgout = 1;
			}
		}
		if (!msgout)
			printk("%s: ports already in use, skipping probe\n", hwif->name);
	} else {
		unsigned long flags;
		save_flags(flags);

		sti();	/* needed for jiffies and irq probing */
		/*
		 * Second drive should only exist if first drive was found,
		 * but a lot of cdrom drives are configured as single slaves.
		 */
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			(void) probe_for_drive (drive);
			if (drive->present && drive->media == ide_disk) {
				if ((!drive->head || drive->head > 16) && !drive->select.b.lba) {
					printk("%s: INVALID GEOMETRY: %d PHYSICAL HEADS?\n",
					 drive->name, drive->head);
					drive->present = 0;
				}
			}
			if (drive->present && !hwif->present) {
				hwif->present = 1;
				request_region(hwif->io_base,  8, hwif->name);
				request_region(hwif->ctl_port, 1, hwif->name);
			}
		}
		restore_flags(flags);
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			if (drive->present && drive->media != ide_tape) {
				ide_tuneproc_t *tuneproc = HWIF(drive)->tuneproc;
				if (tuneproc != NULL && drive->autotune == 1)
					tuneproc(drive, 255);	/* auto-tune PIO mode */
			}
		}
	}
}

/*
 * stridx() returns the offset of c within s,
 * or -1 if c is '\0' or not found within s.
 */
static int stridx (const char *s, char c)
{
	char *i = strchr(s, c);
	return (i && c) ? i - s : -1;
}

/*
 * match_parm() does parsing for ide_setup():
 *
 * 1. the first char of s must be '='.
 * 2. if the remainder matches one of the supplied keywords,
 *     the index (1 based) of the keyword is negated and returned.
 * 3. if the remainder is a series of no more than max_vals numbers
 *     separated by commas, the numbers are saved in vals[] and a
 *     count of how many were saved is returned.  Base10 is assumed,
 *     and base16 is allowed when prefixed with "0x".
 * 4. otherwise, zero is returned.
 */
static int match_parm (char *s, const char *keywords[], int vals[], int max_vals)
{
	static const char *decimal = "0123456789";
	static const char *hex = "0123456789abcdef";
	int i, n;

	if (*s++ == '=') {
		/*
		 * Try matching against the supplied keywords,
		 * and return -(index+1) if we match one
		 */
		if (keywords != NULL) {
			for (i = 0; *keywords != NULL; ++i) {
				if (!strcmp(s, *keywords++))
					return -(i+1);
			}
		}
		/*
		 * Look for a series of no more than "max_vals"
		 * numeric values separated by commas, in base10,
		 * or base16 when prefixed with "0x".
		 * Return a count of how many were found.
		 */
		for (n = 0; (i = stridx(decimal, *s)) >= 0;) {
			vals[n] = i;
			while ((i = stridx(decimal, *++s)) >= 0)
				vals[n] = (vals[n] * 10) + i;
			if (*s == 'x' && !vals[n]) {
				while ((i = stridx(hex, *++s)) >= 0)
					vals[n] = (vals[n] * 0x10) + i;
			}
			if (++n == max_vals)
				break;
			if (*s == ',')
				++s;
		}
		if (!*s)
			return n;
	}
	return 0;	/* zero = nothing matched */
}

/*
 * ide_setup() gets called VERY EARLY during initialization,
 * to handle kernel "command line" strings beginning with "hdx="
 * or "ide".  Here is the complete set currently supported:
 *
 * "hdx="  is recognized for all "x" from "a" to "h", such as "hdc".
 * "idex=" is recognized for all "x" from "0" to "3", such as "ide1".
 *
 * "hdx=noprobe"	: drive may be present, but do not probe for it
 * "hdx=none"		: drive is NOT present, ignore cmos and do not probe
 * "hdx=nowerr"		: ignore the WRERR_STAT bit on this drive
 * "hdx=cdrom"		: drive is present, and is a cdrom drive
 * "hdx=cyl,head,sect"	: disk drive is present, with specified geometry
 * "hdx=autotune"	: driver will attempt to tune interface speed
 *				to the fastest PIO mode supported,
 *				if possible for this drive only.
 *				Not fully supported by all chipset types,
 *				and quite likely to cause trouble with
 *				older/odd IDE drives.
 *
 * "idebus=xx"		: inform IDE driver of VESA/PCI bus speed in Mhz,
 *				where "xx" is between 20 and 66 inclusive,
 *				used when tuning chipset PIO modes.
 *				For PCI bus, 25 is correct for a P75 system,
 *				30 is correct for P90,P120,P180 systems,
 *				and 33 is used for P100,P133,P166 systems.
 *				If in doubt, use idebus=33 for PCI.
 *				As for VLB, it is safest to not specify it.
 *
 * "idex=noprobe"	: do not attempt to access/use this interface
 * "idex=base"		: probe for an interface at the addr specified,
 *				where "base" is usually 0x1f0 or 0x170
 *				and "ctl" is assumed to be "base"+0x206
 * "idex=base,ctl"	: specify both base and ctl
 * "idex=base,ctl,irq"	: specify base, ctl, and irq number
 * "idex=autotune"	: driver will attempt to tune interface speed
 *				to the fastest PIO mode supported,
 *				for all drives on this interface.
 *				Not fully supported by all chipset types,
 *				and quite likely to cause trouble with
 *				older/odd IDE drives.
 * "idex=noautotune"	: driver will NOT attempt to tune interface speed
 *				This is the default for most chipsets,
 *				except the cmd640.
 * "idex=serialize"	: do not overlap operations on idex and ide(x^1)
 *
 * The following are valid ONLY on ide0,
 * and the defaults for the base,ctl ports must not be altered.
 *
 * "ide0=dtc2278"	: probe/support DTC2278 interface
 * "ide0=ht6560b"	: probe/support HT6560B interface
 * "ide0=cmd640_vlb"	: *REQUIRED* for VLB cards with the CMD640 chip
 *			  (not for PCI -- automatically detected)
 * "ide0=qd6580"	: probe/support qd6580 interface
 * "ide0=ali14xx"	: probe/support ali14xx chipsets (ALI M1439, M1443, M1445)
 * "ide0=umc8672"	: probe/support umc8672 chipsets
 */
void ide_setup (char *s)
{
	int i, vals[3];
	ide_hwif_t *hwif;
	ide_drive_t *drive;
	unsigned int hw, unit;
	const char max_drive = 'a' + ((MAX_HWIFS * MAX_DRIVES) - 1);
	const char max_hwif  = '0' + (MAX_HWIFS - 1);

	printk("ide_setup: %s", s);
	init_ide_data ();

	/*
	 * Look for drive options:  "hdx="
	 */
	if (s[0] == 'h' && s[1] == 'd' && s[2] >= 'a' && s[2] <= max_drive) {
		const char *hd_words[] = {"none", "noprobe", "nowerr", "cdrom",
				"serialize", "autotune", "noautotune",
				"slow", "ide-scsi", NULL};
		unit = s[2] - 'a';
		hw   = unit / MAX_DRIVES;
		unit = unit % MAX_DRIVES;
		hwif = &ide_hwifs[hw];
		drive = &hwif->drives[unit];
		switch (match_parm(&s[3], hd_words, vals, 3)) {
			case -1: /* "none" */
				drive->nobios = 1;  /* drop into "noprobe" */
			case -2: /* "noprobe" */
				drive->noprobe = 1;
				goto done;
			case -3: /* "nowerr" */
				drive->bad_wstat = BAD_R_STAT;
				hwif->noprobe = 0;
				goto done;
			case -4: /* "cdrom" */
				drive->present = 1;
				drive->media = ide_cdrom;
				hwif->noprobe = 0;
				goto done;
			case -5: /* "serialize" */
				printk(" -- USE \"ide%d=serialize\" INSTEAD", hw);
				goto do_serialize;
			case -6: /* "autotune" */
				drive->autotune = 1;
				goto done;
			case -7: /* "noautotune" */
				drive->autotune = 2;
				goto done;
			case -8: /* "slow" */
				drive->slow = 1;
				goto done;
			case -9: /* "ide-scsi" */
				drive->ide_scsi = 1;
				goto done;
			case 3: /* cyl,head,sect */
				drive->media	= ide_disk;
				drive->cyl	= drive->bios_cyl  = vals[0];
				drive->head	= drive->bios_head = vals[1];
				drive->sect	= drive->bios_sect = vals[2];
				drive->present	= 1;
				drive->forced_geom = 1;
				hwif->noprobe = 0;
				goto done;
			default:
				goto bad_option;
		}
	}

	if (s[0] != 'i' || s[1] != 'd' || s[2] != 'e')
		goto bad_option;
	/*
	 * Look for bus speed option:  "idebus="
	 */
	if (s[3] == 'b' && s[4] == 'u' && s[5] == 's') {
		if (match_parm(&s[6], NULL, vals, 1) != 1)
			goto bad_option;
		if (vals[0] >= 20 && vals[0] <= 66)
			idebus_parameter = vals[0];
		else
			printk(" -- BAD BUS SPEED! Expected value from 20 to 66");
		goto done;
	}
	/*
	 * Look for interface options:  "idex="
	 */
	if (s[3] >= '0' && s[3] <= max_hwif) {
		/*
		 * Be VERY CAREFUL changing this: note hardcoded indexes below
		 */
		const char *ide_words[] = {"noprobe", "serialize", "autotune", "noautotune",
			"qd6580", "ht6560b", "cmd640_vlb", "dtc2278", "umc8672", "ali14xx", "dc4030", NULL};
		hw = s[3] - '0';
		hwif = &ide_hwifs[hw];
		i = match_parm(&s[4], ide_words, vals, 3);

		/*
		 * Cryptic check to ensure chipset not already set for hwif:
		 */
		if (i > 0 || i <= -5) {
			if (hwif->chipset != ide_unknown)
				goto bad_option;
			if (i <= -5) {
				if (ide_hwifs[1].chipset != ide_unknown)
					goto bad_option;
				/*
				 * Interface keywords work only for ide0:
				 */
				if (hw != 0)
					goto bad_hwif;
			}
		}

		switch (i) {
#ifdef CONFIG_BLK_DEV_PROMISE
			case -11: /* "dc4030" */
			{
				setup_dc4030(hwif);
				goto done;
			}
#endif /* CONFIG_BLK_DEV_PROMISE */
#ifdef CONFIG_BLK_DEV_ALI14XX
			case -10: /* "ali14xx" */
			{
				extern void init_ali14xx (void);
				init_ali14xx();
				goto done;
			}
#endif /* CONFIG_BLK_DEV_ALI14XX */
#ifdef CONFIG_BLK_DEV_UMC8672
			case -9: /* "umc8672" */
			{
				extern void init_umc8672 (void);
				init_umc8672();
				goto done;
			}
#endif /* CONFIG_BLK_DEV_UMC8672 */
#ifdef CONFIG_BLK_DEV_DTC2278
			case -8: /* "dtc2278" */
			{
				extern void init_dtc2278 (void);
				init_dtc2278();
				goto done;
			}
#endif /* CONFIG_BLK_DEV_DTC2278 */
#ifdef CONFIG_BLK_DEV_CMD640
			case -7: /* "cmd640_vlb" */
			{
				extern int cmd640_vlb; /* flag for cmd640.c */
				cmd640_vlb = 1;
				goto done;
			}
#endif /* CONFIG_BLK_DEV_CMD640 */
#ifdef CONFIG_BLK_DEV_HT6560B
			case -6: /* "ht6560b" */
			{
				extern void init_ht6560b (void);
				init_ht6560b();
				goto done;
			}
#endif /* CONFIG_BLK_DEV_HT6560B */
#if CONFIG_BLK_DEV_QD6580
			case -5: /* "qd6580" (has secondary i/f) */
			{
				extern void init_qd6580 (void);
				init_qd6580();
				goto done;
			}
#endif /* CONFIG_BLK_DEV_QD6580 */
			case -4: /* "noautotune" */
				hwif->drives[0].autotune = 2;
				hwif->drives[1].autotune = 2;
				goto done;
			case -3: /* "autotune" */
				hwif->drives[0].autotune = 1;
				hwif->drives[1].autotune = 1;
				goto done;
			case -2: /* "serialize" */
			do_serialize:
				ide_hwifs[hw].serialized = 1;   /* serialize */
				ide_hwifs[hw^1].serialized = 1; /* with mate */
				goto done;

			case -1: /* "noprobe" */
				hwif->noprobe = 1;
				goto done;

			case 1:	/* base */
				vals[1] = vals[0] + 0x206; /* default ctl */
			case 2: /* base,ctl */
				vals[2] = 0;	/* default irq = probe for it */
			case 3: /* base,ctl,irq */
				hwif->io_base  = vals[0];
				hwif->ctl_port = vals[1];
				hwif->irq      = vals[2];
				hwif->noprobe  = 0;
				hwif->chipset  = ide_generic;
				goto done;

			case 0: goto bad_option;
			default:
				printk(" -- SUPPORT NOT CONFIGURED IN THIS KERNEL\n");
				return;
		}
	}
bad_option:
	printk(" -- BAD OPTION\n");
	return;
bad_hwif:
	printk("-- NOT SUPPORTED ON ide%d", hw);
done:
	printk("\n");
}

/*
 * This routine is called from the partition-table code in genhd.c
 * to "convert" a drive to a logical geometry with fewer than 1024 cyls.
 *
 * The second parameter, "xparm", determines exactly how the translation
 * will be handled:
 *		 0 = convert to CHS with fewer than 1024 cyls
 *			using the same method as Ontrack DiskManager.
 *		 1 = same as "0", plus offset everything by 63 sectors.
 *		-1 = similar to "0", plus redirect sector 0 to sector 1.
 *		>1 = convert to a CHS geometry with "xparm" heads.
 *
 * Returns 0 if the translation was not possible, if the device was not
 * an IDE disk drive, or if a geometry was "forced" on the commandline.
 * Returns 1 if the geometry translation was successful.
 */
int ide_xlate_1024 (kdev_t i_rdev, int xparm, const char *msg)
{
	ide_drive_t *drive;
	static const byte head_vals[] = {4, 8, 16, 32, 64, 128, 255, 0};
	const byte *heads = head_vals;
	unsigned long tracks;

	if ((drive = get_info_ptr(i_rdev)) == NULL || drive->forced_geom)
		return 0;

	if (xparm > 1 && xparm <= drive->bios_head && drive->bios_sect == 63)
		return 0;		/* we already have a translation */

	printk("%s ", msg);

	if (drive->id) {
		drive->cyl  = drive->id->cyls;
		drive->head = drive->id->heads;
		drive->sect = drive->id->sectors;
	}
	drive->bios_cyl  = drive->cyl;
	drive->bios_head = drive->head;
	drive->bios_sect = drive->sect;
	drive->special.b.set_geometry = 1;

	tracks = drive->bios_cyl * drive->bios_head * drive->bios_sect / 63;
	drive->bios_sect = 63;
	if (xparm > 1) {
		drive->bios_head = xparm;
		drive->bios_cyl = tracks / drive->bios_head;
	} else {
		while (drive->bios_cyl >= 1024) {
			drive->bios_head = *heads;
			drive->bios_cyl = tracks / drive->bios_head;
			if (0 == *++heads)
				break;
		}
#if FAKE_FDISK_FOR_EZDRIVE
		if (xparm == -1) {
			drive->remap_0_to_1 = 1;
			msg = "0->1";
		} else
#endif /* FAKE_FDISK_FOR_EZDRIVE */
		if (xparm == 1) {
			drive->sect0 = 63;
			drive->bios_cyl = (tracks - 1) / drive->bios_head;
			msg = "+63";
		}
		printk("[remap %s] ", msg);
	}
	drive->part[0].nr_sects = current_capacity(drive);
	printk("[%d/%d/%d]", drive->bios_cyl, drive->bios_head, drive->bios_sect);
	return 1;
}

#if MAX_HWIFS > 1
/*
 * save_match() is used to simplify logic in init_irq() below.
 *
 * A loophole here is that we may not know about a particular
 * hwif's irq until after that hwif is actually probed/initialized..
 * This could be a problem for the case where an hwif is on a
 * dual interface that requires serialization (eg. cmd640) and another
 * hwif using one of the same irqs is initialized beforehand.
 *
 * This routine detects and reports such situations, but does not fix them.
 */
static void save_match (ide_hwif_t *hwif, ide_hwif_t *new, ide_hwif_t **match)
{
	ide_hwif_t *m = *match;

	if (m && m->hwgroup && m->hwgroup != new->hwgroup) {
		if (!new->hwgroup)
			return;
		printk("%s: potential irq problem with %s and %s\n", hwif->name, new->name, m->name);
	}
	if (!m || m->irq != hwif->irq) /* don't undo a prior perfect match */
		*match = new;
}
#endif /* MAX_HWIFS > 1 */

/*
 * This routine sets up the irq for an ide interface, and creates a new
 * hwgroup for the irq/hwif if none was previously assigned.
 *
 * Much of the code is for correctly detecting/handling irq sharing
 * and irq serialization situations.  This is somewhat complex because
 * it handles static as well as dynamic (PCMCIA) IDE interfaces.
 *
 * The SA_INTERRUPT in sa_flags means ide_intr() is always entered with
 * interrupts completely disabled.  This can be bad for interrupt latency,
 * but anything else has led to problems on some machines.  We re-enable
 * interrupts as much as we can safely do in most places.
 */
static int init_irq (ide_hwif_t *hwif)
{
	unsigned long flags;
#if MAX_HWIFS > 1
	unsigned int index;
#endif /* MAX_HWIFS > 1 */
	ide_hwgroup_t *hwgroup;
	ide_hwif_t *match = NULL;

	save_flags(flags);
	cli();

	hwif->hwgroup = NULL;
#if MAX_HWIFS > 1
	/*
	 * Group up with any other hwifs that share our irq(s).
	 */
	for (index = 0; index < MAX_HWIFS; index++) {
		ide_hwif_t *h = &ide_hwifs[index];
		if (h->hwgroup) {  /* scan only initialized hwif's */
			if (hwif->irq == h->irq) {
				hwif->sharing_irq = h->sharing_irq = 1;
				save_match(hwif, h, &match);
			}
			if (hwif->serialized) {
				ide_hwif_t *mate = &ide_hwifs[hwif->index^1];
				if (index == mate->index || h->irq == mate->irq)
					save_match(hwif, h, &match);
			}
			if (h->serialized) {
				ide_hwif_t *mate = &ide_hwifs[h->index^1];
				if (hwif->irq == mate->irq)
					save_match(hwif, h, &match);
			}
		}
	}
#endif /* MAX_HWIFS > 1 */
	/*
	 * If we are still without a hwgroup, then form a new one
	 */
	if (match) {
		hwgroup = match->hwgroup;
	} else {
		hwgroup = kmalloc(sizeof(ide_hwgroup_t), GFP_KERNEL);
		hwgroup->hwif 	 = hwgroup->next_hwif = hwif->next = hwif;
		hwgroup->rq      = NULL;
		hwgroup->handler = NULL;
		if (hwif->drives[0].present)
			hwgroup->drive = &hwif->drives[0];
		else
			hwgroup->drive = &hwif->drives[1];
		hwgroup->poll_timeout = 0;
		hwgroup->active = 0;
		init_timer(&hwgroup->timer);
		hwgroup->timer.function = &timer_expiry;
		hwgroup->timer.data = (unsigned long) hwgroup;
	}

	/*
	 * Allocate the irq, if not already obtained for another hwif
	 */
	if (!match || match->irq != hwif->irq) {
		if (request_irq(hwif->irq, ide_intr, SA_INTERRUPT, hwif->name, hwgroup)) {
			if (!match)
				kfree(hwgroup);
			restore_flags(flags);
			return 1;
		}
	}

	/*
	 * Everything is okay, so link us into the hwgroup
	 */
	hwif->hwgroup = hwgroup;
	hwif->next = hwgroup->hwif->next;
	hwgroup->hwif->next = hwif;

	restore_flags(flags);	/* safe now that hwif->hwgroup is set up */

	printk("%s at 0x%03x-0x%03x,0x%03x on irq %d", hwif->name,
		hwif->io_base, hwif->io_base+7, hwif->ctl_port, hwif->irq);
	if (match)
		printk(" (%sed with %s)", hwif->sharing_irq ? "shar" : "serializ", match->name);
	printk("\n");
	return 0;
}

static struct file_operations ide_fops = {
	NULL,			/* lseek - default */
	block_read,		/* read - general block-dev read */
	block_write,		/* write - general block-dev write */
	NULL,			/* readdir - bad */
	NULL,			/* select */
	ide_ioctl,		/* ioctl */
	NULL,			/* mmap */
	ide_open,		/* open */
	ide_release,		/* release */
	block_fsync		/* fsync */
	,NULL,			/* fasync */
	ide_check_media_change,	/* check_media_change */
	revalidate_disk		/* revalidate */
};

#ifdef CONFIG_PCI
#if defined(CONFIG_BLK_DEV_RZ1000) || defined(CONFIG_BLK_DEV_TRITON)

typedef void (ide_pci_init_proc_t)(byte, byte);

/*
 * ide_probe_pci() scans PCI for a specific vendor/device function,
 * and invokes the supplied init routine for each instance detected.
 */
static void ide_probe_pci (unsigned short vendor, unsigned short device, ide_pci_init_proc_t *init, int func_adj)
{
	unsigned long flags;
	unsigned index;
	byte fn, bus;

	save_flags(flags);
	cli();
	for (index = 0; !pcibios_find_device (vendor, device, index, &bus, &fn); ++index) {
		init (bus, fn + func_adj);
	}
	restore_flags(flags);
}

#endif /* defined(CONFIG_BLK_DEV_RZ1000) || defined(CONFIG_BLK_DEV_TRITON) */

static void ide_probe_promise_20246(void)
{
	byte fn, bus;
	unsigned short io[6], count = 0;
	unsigned int reg, tmp, i;
	ide_hwif_t *hwif;

	memset(io, 0, 6 * sizeof(unsigned short));
	if (pcibios_find_device(PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20246, 0, &bus, &fn))
		return;
	printk("ide: Promise Technology IDE Ultra-DMA 33 on PCI bus %d function %d\n", bus, fn);
	for (reg = PCI_BASE_ADDRESS_0; reg <= PCI_BASE_ADDRESS_5; reg += 4) {
		pcibios_read_config_dword(bus, fn, reg, &tmp);
		if (tmp & PCI_BASE_ADDRESS_SPACE_IO)
			io[count++] = tmp & PCI_BASE_ADDRESS_IO_MASK;
	}
	for (i = 2; i < 4; i++) {
		hwif = ide_hwifs + i;
		if (hwif->chipset == ide_generic) {
			printk("ide%d: overridden with command line parameter\n", i);
			return;
		}
		tmp = (i - 2) * 2;
		if (!io[tmp] || !io[tmp + 1]) {
			printk("ide%d: invalid port address %x, %x -- aborting\n", i, io[tmp], io[tmp + 1]);
			return;
		}
		hwif->io_base = io[tmp];
		hwif->ctl_port = io[tmp + 1] + 2;
		hwif->noprobe = 0;
	}
#ifdef CONFIG_BLK_DEV_TRITON
	ide_init_promise (bus, fn, &ide_hwifs[2], &ide_hwifs[3], io[4]);
#endif /* CONFIG_BLK_DEV_TRITON */
}

#endif /* CONFIG_PCI */

/*
 * ide_init_pci() finds/initializes "known" PCI IDE interfaces
 *
 * This routine should ideally be using pcibios_find_class() to find
 * all IDE interfaces, but that function causes some systems to "go weird".
 */
static void probe_for_hwifs (void)
{
#ifdef CONFIG_PCI
	/*
	 * Find/initialize PCI IDE interfaces
	 */
	if (pcibios_present()) {
#ifdef CONFIG_BLK_DEV_RZ1000
		ide_pci_init_proc_t init_rz1000;
		ide_probe_pci (PCI_VENDOR_ID_PCTECH, PCI_DEVICE_ID_PCTECH_RZ1000, &init_rz1000, 0);
		ide_probe_pci (PCI_VENDOR_ID_PCTECH, PCI_DEVICE_ID_PCTECH_RZ1001, &init_rz1000, 0);
#endif /* CONFIG_BLK_DEV_RZ1000 */
#ifdef CONFIG_BLK_DEV_TRITON
		/*
		 * Apparently the BIOS32 services on Intel motherboards are
		 * buggy and won't find the PCI_DEVICE_ID_INTEL_82371_1 for us.
		 * So instead, we search for PCI_DEVICE_ID_INTEL_82371_0,
		 * and then add 1.
		 */
		ide_probe_pci (PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371_0, &ide_init_triton, 1);
		ide_probe_pci (PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371SB_1, &ide_init_triton, 0);
		ide_probe_pci (PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB, &ide_init_triton, 0);
#endif /* CONFIG_BLK_DEV_TRITON */
		ide_probe_promise_20246();
	}
#endif /* CONFIG_PCI */
#ifdef CONFIG_BLK_DEV_CMD640
	{
		extern void ide_probe_for_cmd640x (void);
		ide_probe_for_cmd640x();
	}
#endif
#ifdef CONFIG_BLK_DEV_PROMISE
	init_dc4030();
#endif
}

static int hwif_init (int h)
{
	ide_hwif_t *hwif = &ide_hwifs[h];
	void (*rfn)(void);

	if (!hwif->present)
		return 0;
	if (!hwif->irq) {
		if (!(hwif->irq = default_irqs[h])) {
			printk("%s: DISABLED, NO IRQ\n", hwif->name);
			return (hwif->present = 0);
		}
	}
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->irq == HD_IRQ && hwif->io_base != HD_DATA) {
		printk("%s: CANNOT SHARE IRQ WITH OLD HARDDISK DRIVER (hd.c)\n", hwif->name);
		return (hwif->present = 0);
	}
#endif /* CONFIG_BLK_DEV_HD */

	hwif->present = 0; /* we set it back to 1 if all is ok below */
	switch (hwif->major) {
	case IDE0_MAJOR: rfn = &do_ide0_request; break;
#if MAX_HWIFS > 1
	case IDE1_MAJOR: rfn = &do_ide1_request; break;
#endif
#if MAX_HWIFS > 2
	case IDE2_MAJOR: rfn = &do_ide2_request; break;
#endif
#if MAX_HWIFS > 3
	case IDE3_MAJOR: rfn = &do_ide3_request; break;
#endif
	default:
		printk("%s: request_fn NOT DEFINED\n", hwif->name);
		return (hwif->present = 0);
	}
	if (register_blkdev (hwif->major, hwif->name, &ide_fops)) {
		printk("%s: UNABLE TO GET MAJOR NUMBER %d\n", hwif->name, hwif->major);
	} else if (init_irq (hwif)) {
		printk("%s: UNABLE TO GET IRQ %d\n", hwif->name, hwif->irq);
		(void) unregister_blkdev (hwif->major, hwif->name);
	} else {
		init_gendisk(hwif);
		blk_dev[hwif->major].request_fn = rfn;
		read_ahead[hwif->major] = 8;	/* (4kB) */
		hwif->present = 1;	/* success */
	}
	return hwif->present;
}

/*
 * This is gets invoked once during initialization, to set *everything* up
 */
int ide_init (void)
{
	int index;

	init_ide_data ();
	/*
	 * Probe for special "known" interface chipsets
	 */
	probe_for_hwifs ();

	/*
	 * Probe for drives in the usual way.. CMOS/BIOS, then poke at ports
	 */
	for (index = 0; index < MAX_HWIFS; ++index)
		probe_hwif (&ide_hwifs[index]);
	for (index = 0; index < MAX_HWIFS; ++index)
		hwif_init (index);

#ifdef CONFIG_BLK_DEV_IDETAPE
	idetape_register_chrdev();	/* Register character device interface to the ide tape */
#endif /* CONFIG_BLK_DEV_IDETAPE */

	return 0;
}

#ifdef CONFIG_BLK_DEV_IDE_PCMCIA
int ide_register(int io_base, int ctl_port, int irq)
{
	int index, i, rc = -1;
	ide_hwif_t *hwif;
	ide_drive_t *drive;
	unsigned long flags;

	save_flags(flags);
	cli();
	for (index = 0; index < MAX_HWIFS; ++index) {
		hwif = &ide_hwifs[index];
		if (hwif->present) {
			if (hwif->io_base == io_base || hwif->ctl_port == ctl_port)
				break; /* this ide port already exists */
		} else {
			hwif->io_base = io_base;
			hwif->ctl_port = ctl_port;
			hwif->irq = irq;
			hwif->noprobe = 0;
			probe_hwif(hwif);
			if (!hwif_init(index))
				break;
			for (i = 0; i < hwif->gd->nr_real; i++) {
				drive = &hwif->drives[i];
				revalidate_disk(MKDEV(hwif->major, i<<PARTN_BITS));
#ifdef CONFIG_BLK_DEV_IDECD
				if (drive->present && drive->media == ide_cdrom)
					ide_cdrom_setup(drive);
#endif /* CONFIG_BLK_DEV_IDECD */
			}
			rc = index;
			break;
		}
	}
	restore_flags(flags);
	return rc;
}

void ide_unregister (unsigned int index)
{
	struct gendisk *gd, **gdp;
	ide_hwif_t *hwif, *g;
	ide_hwgroup_t *hwgroup;
	int irq_count = 0;
	unsigned long flags;

	if (index >= MAX_HWIFS)
		return;
	save_flags(flags);
	cli();
	hwif = &ide_hwifs[index];
	if (!hwif->present || hwif->drives[0].busy || hwif->drives[1].busy) {
		restore_flags(flags);
		return;
	}
	hwif->present = 0;
	hwgroup = hwif->hwgroup;

	/*
	 * free the irq if we were the only hwif using it
	 */
	g = hwgroup->hwif;
	do {
		if (g->irq == hwif->irq)
			++irq_count;
		g = g->next;
	} while (g != hwgroup->hwif);
	if (irq_count == 1)
		free_irq(hwif->irq, hwgroup);

	/*
	 * Note that we only release the standard ports,
	 * and do not even try to handle any extra ports
	 * allocated for weird IDE interface chipsets.
	 */
	release_region(hwif->io_base, 8);
	release_region(hwif->ctl_port, 1);

	/*
	 * Remove us from the hwgroup, and free
	 * the hwgroup if we were the only member
	 */
	while (hwgroup->hwif->next != hwif)
		hwgroup->hwif = hwgroup->hwif->next;
	hwgroup->hwif->next = hwif->next;
	if (hwgroup->hwif == hwif)
		hwgroup->hwif = hwif->next;
	if (hwgroup->next_hwif == hwif)
		hwgroup->next_hwif = hwif->next;
	if (hwgroup->hwif == hwif)
		kfree(hwgroup);

	/*
	 * Remove us from the kernel's knowledge
	 */
	unregister_blkdev(hwif->major, hwif->name);
	kfree(blksize_size[hwif->major]);
	blk_dev[hwif->major].request_fn = NULL;
	blksize_size[hwif->major] = NULL;
	for (gdp = &gendisk_head; *gdp; gdp = &((*gdp)->next))
		if (*gdp == hwif->gd)
			break;
	if (*gdp == NULL)
		printk("gd not in disk chain!\n");
	else {
		gd = *gdp; *gdp = gd->next;
		kfree(gd->sizes);
		kfree(gd->part);
		kfree(gd);
	}
	init_hwif_data (index);	/* restore hwif data to pristine status */
	restore_flags(flags);
}
#endif /* CONFIG_BLK_DEV_IDE_PCMCIA */