aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/cdrom/cdrom.c
blob: 3170eaa250873bf5f0dae15b88aacf66d2a3ef1e (plain) (tree)
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
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
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
























































































































































































































































































































































































































                                                                                               












































































































































































































































                                                                                
                                       











































































































































































































































































































































































                                                                                                            
                                                 
                                                
                                                 













                                                                     

                               







































































































                                                                                                          
                                           




































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                                      



                                                  










                                                                      


                                                        




















                                                      
                                                          




                                                            
                                                









                                      
                            









































                                                                                  

                                                                  
 

                                          

                














                                                                           

                           



















                                                                               
                                   
         
 

                                           
 


                                                               
 



                                           
 



                                                              
 



                                      
 




                                                                
 




                                                                   
 
                                                              
 

                                          
 


                                                               
 

                                               
 


                                                  
 





                                                
 



                                                                 
 
















                                                                      
                                       



                                  
 



                                                                   
 


                                   
 



                                                                  
 



                                                
 


































































                                                                         
 







                                                                    



                                                                      




                                                             
 
                                                        
 




                                              
 




                                                          
 















































                                                                          

         





















































































































































































































































                                                                                

                                               
                                   
                                   

         




                                                                   
                      













                                                            


                        


                                                      
 














































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                          
/* linux/drivers/cdrom/cdrom.c. 
   Copyright (c) 1996, 1997 David A. van Leeuwen.
   Copyright (c) 1997, 1998 Erik Andersen <andersee@debian.org>
   Copyright (c) 1998, 1999 Jens Axboe <axboe@image.dk>

   May be copied or modified under the terms of the GNU General Public
   License.  See linux/COPYING for more information.

   Uniform CD-ROM driver for Linux.
   See Documentation/cdrom/cdrom-standard.tex for usage information.

   The routines in the file provide a uniform interface between the
   software that uses CD-ROMs and the various low-level drivers that
   actually talk to the hardware. Suggestions are welcome.
   Patches that work are more welcome though.  ;-)

 To Do List:
 ----------------------------------

 -- Modify sysctl/proc interface. I plan on having one directory per
 drive, with entries for outputing general drive information, and sysctl
 based tunable parameters such as whether the tray should auto-close for
 that drive. Suggestions (or patches) for this welcome!


 Revision History
 ----------------------------------
 1.00  Date Unknown -- David van Leeuwen <david@tm.tno.nl>
 -- Initial version by David A. van Leeuwen. I don't have a detailed
  changelog for the 1.x series, David?

2.00  Dec  2, 1997 -- Erik Andersen <andersee@debian.org>
  -- New maintainer! As David A. van Leeuwen has been too busy to activly
  maintain and improve this driver, I am now carrying on the torch. If
  you have a problem with this driver, please feel free to contact me.

  -- Added (rudimentary) sysctl interface. I realize this is really weak
  right now, and is _very_ badly implemented. It will be improved...

  -- Modified CDROM_DISC_STATUS so that it is now incorporated into
  the Uniform CD-ROM driver via the cdrom_count_tracks function.
  The cdrom_count_tracks function helps resolve some of the false
  assumptions of the CDROM_DISC_STATUS ioctl, and is also used to check
  for the correct media type when mounting or playing audio from a CD.

  -- Remove the calls to verify_area and only use the copy_from_user and
  copy_to_user stuff, since these calls now provide their own memory
  checking with the 2.1.x kernels.

  -- Major update to return codes so that errors from low-level drivers
  are passed on through (thanks to Gerd Knorr for pointing out this
  problem).

  -- Made it so if a function isn't implemented in a low-level driver,
  ENOSYS is now returned instead of EINVAL.

  -- Simplified some complex logic so that the source code is easier to read.

  -- Other stuff I probably forgot to mention (lots of changes).

2.01 to 2.11 Dec 1997-Jan 1998
  -- TO-DO!  Write changelogs for 2.01 to 2.12.

2.12  Jan  24, 1998 -- Erik Andersen <andersee@debian.org>
  -- Fixed a bug in the IOCTL_IN and IOCTL_OUT macros.  It turns out that
  copy_*_user does not return EFAULT on error, but instead returns the number 
  of bytes not copied.  I was returning whatever non-zero stuff came back from 
  the copy_*_user functions directly, which would result in strange errors.

2.13  July 17, 1998 -- Erik Andersen <andersee@debian.org>
  -- Fixed a bug in CDROM_SELECT_SPEED where you couldn't lower the speed
  of the drive.  Thanks to Tobias Ringstr|m <tori@prosolvia.se> for pointing
  this out and providing a simple fix.
  -- Fixed the procfs-unload-module bug with the fill_inode procfs callback.
  thanks to Andrea Arcangeli
  -- Fixed it so that the /proc entry now also shows up when cdrom is
  compiled into the kernel.  Before it only worked when loaded as a module.

  2.14 August 17, 1998 -- Erik Andersen <andersee@debian.org>
  -- Fixed a bug in cdrom_media_changed and handling of reporting that
  the media had changed for devices that _don't_ implement media_changed.  
  Thanks to Grant R. Guenther <grant@torque.net> for spotting this bug.
  -- Made a few things more pedanticly correct.

2.50 Oct 19, 1998 - Jens Axboe <axboe@image.dk>
  -- New maintainers! Erik was too busy to continue the work on the driver,
  so now Chris Zwilling <chris@cloudnet.com> and Jens Axboe <axboe@image.dk>
  will do their best to follow in his footsteps
  
  2.51 Dec 20, 1998 - Jens Axboe <axboe@image.dk>
  -- Check if drive is capable of doing what we ask before blindly changing
  cdi->options in various ioctl.
  -- Added version to proc entry.
  
  2.52 Jan 16, 1999 - Jens Axboe <axboe@image.dk>
  -- Fixed an error in open_for_data where we would sometimes not return
  the correct error value. Thanks Huba Gaspar <huba@softcell.hu>.
  -- Fixed module usage count - usage was based on /proc/sys/dev
  instead of /proc/sys/dev/cdrom. This could lead to an oops when other
  modules had entries in dev. Feb 02 - real bug was in sysctl.c where
  dev would be removed even though it was used. cdrom.c just illuminated
  that bug.
  
  2.53 Feb 22, 1999 - Jens Axboe <axboe@image.dk>
  -- Fixup of several ioctl calls, in particular CDROM_SET_OPTIONS has
  been "rewritten" because capabilities and options aren't in sync. They
  should be...
  -- Added CDROM_LOCKDOOR ioctl. Locks the door and keeps it that way.
  -- Added CDROM_RESET ioctl.
  -- Added CDROM_DEBUG ioctl. Enable debug messages on-the-fly.
  -- Added CDROM_GET_CAPABILITY ioctl. This relieves userspace programs
  from parsing /proc/sys/dev/cdrom/info.
  
  2.54 Mar 15, 1999 - Jens Axboe <axboe@image.dk>
  -- Check capability mask from low level driver when counting tracks as
  per suggestion from Corey J. Scotts <cstotts@blue.weeg.uiowa.edu>.
  
  2.55 Apr 25, 1999 - Jens Axboe <axboe@image.dk>
  -- autoclose was mistakenly checked against CDC_OPEN_TRAY instead of
  CDC_CLOSE_TRAY.
  -- proc info didn't mask against capabilities mask.
  
  3.00 Aug 5, 1999 - Jens Axboe <axboe@image.dk>
  -- Unified audio ioctl handling across CD-ROM drivers. A lot of the
  code was duplicated before. Drives that support the generic packet
  interface are now being fed packets from here instead.
  -- First attempt at adding support for MMC2 commands - for DVD and
  CD-R(W) drives. Only the DVD parts are in now - the interface used is
  the same as for the audio ioctls.
  -- ioctl cleanups. if a drive couldn't play audio, it didn't get
  a change to perform device specific ioctls as well.
  -- Defined CDROM_CAN(CDC_XXX) for checking the capabilities.
  -- Put in sysctl files for autoclose, autoeject, check_media, debug,
  and lock.
  -- /proc/sys/dev/cdrom/info has been updated to also contain info about
  CD-Rx and DVD capabilities.
  -- Now default to checking media type.
  -- CDROM_SEND_PACKET ioctl added. The infrastructure was in place for
  doing this anyway, with the generic_packet addition.
  
  3.01 Aug 6, 1999 - Jens Axboe <axboe@image.dk>
  -- Fix up the sysctl handling so that the option flags get set
  correctly.
  -- Fix up ioctl handling so the device specific ones actually get
  called :).
  
  3.02 Aug 8, 1999 - Jens Axboe <axboe@image.dk>
  -- Fixed volume control on SCSI drives (or others with longer audio
  page).
  -- Fixed a couple of DVD minors. Thanks to Andrew T. Veliath
  <andrewtv@usa.net> for telling me and for having defined the various
  DVD structures and ioctls in the first place! He designed the original
  DVD patches for ide-cd and while I rearranged and unified them, the
  interface is still the same.
  
  3.03 Sep 1, 1999 - Jens Axboe <axboe@image.dk>
  -- Moved the rest of the audio ioctls from the CD-ROM drivers here. Only
  CDROMREADTOCENTRY and CDROMREADTOCHDR are left.
  -- Moved the CDROMREADxxx ioctls in here.
  -- Defined the cdrom_get_last_written and cdrom_get_next_block as ioctls
  and exported functions.
  -- Erik Andersen <andersen@xmission.com> modified all SCMD_ commands
  to now read GPCMD_ for the new generic packet interface. All low level
  drivers are updated as well.
  -- Various other cleanups.

  3.04 Sep 12, 1999 - Jens Axboe <axboe@image.dk>
  -- Fixed a couple of possible memory leaks (if an operation failed and
  we didn't free the buffer before returning the error).
  -- Integrated Uniform CD Changer handling from Richard Sharman
  <rsharman@pobox.com>.
  -- Defined CD_DVD and CD_CHANGER log levels.
  -- Fixed the CDROMREADxxx ioctls.
  -- CDROMPLAYTRKIND uses the GPCMD_PLAY_AUDIO_MSF command - too few
  drives supported it. We lose the index part, however.
  -- Small modifications to accommodate opens of /dev/hdc1, required
  for ide-cd to handle multisession discs.
  -- Export cdrom_mode_sense and cdrom_mode_select.
  -- init_cdrom_command() for setting up a cgc command.
  
  3.05 Oct 24, 1999 - Jens Axboe <axboe@image.dk>
  -- Changed the interface for CDROM_SEND_PACKET. Before it was virtually
  impossible to send the drive data in a sensible way.
  -- Lowered stack usage in mmc_ioctl(), dvd_read_disckey(), and
  dvd_read_manufact.
  -- Added setup of write mode for packet writing.
  -- Fixed CDDA ripping with cdda2wav - accept much larger requests of
  number of frames and split the reads in blocks of 8.

  3.06 Dec 13, 1999 - Jens Axboe <axboe@image.dk>
  -- Added support for changing the region of DVD drives.
  -- Added sense data to generic command.

  3.07 Feb 2, 2000 - Jens Axboe <axboe@suse.de>
  -- Do same "read header length" trick in cdrom_get_disc_info() as
  we do in cdrom_get_track_info() -- some drive don't obey specs and
  fail if they can't supply the full Mt Fuji size table.
  -- Deleted stuff related to setting up write modes. It has a different
  home now.
  -- Clear header length in mode_select unconditionally.
  -- Removed the register_disk() that was added, not needed here.

  3.08 May 1, 2000 - Jens Axboe <axboe@suse.de>
  -- Fix direction flag in setup_send_key and setup_report_key. This
  gave some SCSI adapters problems.
  -- Always return -EROFS for write opens
  -- Convert to module_init/module_exit style init and remove some
  of the #ifdef MODULE stuff
  -- Fix several dvd errors - DVD_LU_SEND_ASF should pass agid,
  DVD_HOST_SEND_RPC_STATE did not set buffer size in cdb, and
  dvd_do_auth passed uninitialized data to drive because init_cdrom_command
  did not clear a 0 sized buffer.
  
  3.09 May 12, 2000 - Jens Axboe <axboe@suse.de>
  -- Fix Video-CD on SCSI drives that don't support READ_CD command. In
  that case switch block size and issue plain READ_10 again, then switch
  back.

  3.10 Jun 10, 2000 - Jens Axboe <axboe@suse.de>
  -- Fix volume control on CD's - old SCSI-II drives now use their own
  code, as doing MODE6 stuff in here is really not my intention.
  -- Use READ_DISC_INFO for more reliable end-of-disc.

  3.11 Jun 12, 2000 - Jens Axboe <axboe@suse.de>
  -- Fix bug in getting rpc phase 2 region info.
  -- Reinstate "correct" CDROMPLAYTRKIND

   3.12 Oct 18, 2000 - Jens Axboe <axboe@suse.de>
  -- Use quiet bit on packet commands not known to work

   3.20 Dec 17, 2003 - Jens Axboe <axboe@suse.de>
  -- Various fixes and lots of cleanups not listed :-)
  -- Locking fixes
  -- Mt Rainier support
  -- DVD-RAM write open fixes

  Nov 5 2001, Aug 8 2002. Modified by Andy Polyakov
  <appro@fy.chalmers.se> to support MMC-3 compliant DVD+RW units.

  Modified by Nigel Kukard <nkukard@lbsd.net> - support DVD+RW
  2.4.x patch by Andy Polyakov <appro@fy.chalmers.se>

-------------------------------------------------------------------------*/

#define REVISION "Revision: 3.20"
#define VERSION "Id: cdrom.c 3.20 2003/12/17"

/* I use an error-log mask to give fine grain control over the type of
   messages dumped to the system logs.  The available masks include: */
#define CD_NOTHING      0x0
#define CD_WARNING	0x1
#define CD_REG_UNREG	0x2
#define CD_DO_IOCTL	0x4
#define CD_OPEN		0x8
#define CD_CLOSE	0x10
#define CD_COUNT_TRACKS 0x20
#define CD_CHANGER	0x40
#define CD_DVD		0x80

/* Define this to remove _all_ the debugging messages */
/* #define ERRLOGMASK CD_NOTHING */
#define ERRLOGMASK CD_WARNING
/* #define ERRLOGMASK (CD_WARNING|CD_OPEN|CD_COUNT_TRACKS|CD_CLOSE) */
/* #define ERRLOGMASK (CD_WARNING|CD_REG_UNREG|CD_DO_IOCTL|CD_OPEN|CD_CLOSE|CD_COUNT_TRACKS) */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/major.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h> 
#include <linux/cdrom.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/blkpg.h>
#include <linux/init.h>
#include <linux/fcntl.h>
#include <linux/blkdev.h>
#include <linux/times.h>

#include <asm/uaccess.h>

/* used to tell the module to turn on full debugging messages */
static int debug;
/* used to keep tray locked at all times */
static int keeplocked;
/* default compatibility mode */
static int autoclose=1;
static int autoeject;
static int lockdoor = 1;
/* will we ever get to use this... sigh. */
static int check_media_type;
/* automatically restart mrw format */
static int mrw_format_restart = 1;
module_param(debug, bool, 0);
module_param(autoclose, bool, 0);
module_param(autoeject, bool, 0);
module_param(lockdoor, bool, 0);
module_param(check_media_type, bool, 0);
module_param(mrw_format_restart, bool, 0);

static DEFINE_SPINLOCK(cdrom_lock);

static const char *mrw_format_status[] = {
	"not mrw",
	"bgformat inactive",
	"bgformat active",
	"mrw complete",
};

static const char *mrw_address_space[] = { "DMA", "GAA" };

#if (ERRLOGMASK!=CD_NOTHING)
#define cdinfo(type, fmt, args...) \
        if ((ERRLOGMASK & type) || debug==1 ) \
            printk(KERN_INFO "cdrom: " fmt, ## args)
#else
#define cdinfo(type, fmt, args...) 
#endif

/* These are used to simplify getting data in from and back to user land */
#define IOCTL_IN(arg, type, in)					\
	if (copy_from_user(&(in), (type __user *) (arg), sizeof (in)))	\
		return -EFAULT;

#define IOCTL_OUT(arg, type, out) \
	if (copy_to_user((type __user *) (arg), &(out), sizeof (out)))	\
		return -EFAULT;

/* The (cdo->capability & ~cdi->mask & CDC_XXX) construct was used in
   a lot of places. This macro makes the code more clear. */
#define CDROM_CAN(type) (cdi->ops->capability & ~cdi->mask & (type))

/* used in the audio ioctls */
#define CHECKAUDIO if ((ret=check_for_audio_disc(cdi, cdo))) return ret

/* Not-exported routines. */
static int open_for_data(struct cdrom_device_info * cdi);
static int check_for_audio_disc(struct cdrom_device_info * cdi,
			 struct cdrom_device_ops * cdo);
static void sanitize_format(union cdrom_addr *addr, 
		u_char * curr, u_char requested);
static int mmc_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
		     unsigned long arg);

int cdrom_get_last_written(struct cdrom_device_info *, long *);
static int cdrom_get_next_writable(struct cdrom_device_info *, long *);
static void cdrom_count_tracks(struct cdrom_device_info *, tracktype*);

static int cdrom_mrw_exit(struct cdrom_device_info *cdi);

static int cdrom_get_disc_info(struct cdrom_device_info *cdi, disc_information *di);

#ifdef CONFIG_SYSCTL
static void cdrom_sysctl_register(void);
#endif /* CONFIG_SYSCTL */ 
static struct cdrom_device_info *topCdromPtr;

static int cdrom_dummy_generic_packet(struct cdrom_device_info *cdi,
				      struct packet_command *cgc)
{
	if (cgc->sense) {
		cgc->sense->sense_key = 0x05;
		cgc->sense->asc = 0x20;
		cgc->sense->ascq = 0x00;
	}

	cgc->stat = -EIO;
	return -EIO;
}

/* This macro makes sure we don't have to check on cdrom_device_ops
 * existence in the run-time routines below. Change_capability is a
 * hack to have the capability flags defined const, while we can still
 * change it here without gcc complaining at every line.
 */
#define ENSURE(call, bits) if (cdo->call == NULL) *change_capability &= ~(bits)

int register_cdrom(struct cdrom_device_info *cdi)
{
	static char banner_printed;
        struct cdrom_device_ops *cdo = cdi->ops;
        int *change_capability = (int *)&cdo->capability; /* hack */

	cdinfo(CD_OPEN, "entering register_cdrom\n"); 

	if (cdo->open == NULL || cdo->release == NULL)
		return -2;
	if (!banner_printed) {
		printk(KERN_INFO "Uniform CD-ROM driver " REVISION "\n");
		banner_printed = 1;
#ifdef CONFIG_SYSCTL
		cdrom_sysctl_register();
#endif /* CONFIG_SYSCTL */ 
	}

	ENSURE(drive_status, CDC_DRIVE_STATUS );
	ENSURE(media_changed, CDC_MEDIA_CHANGED);
	ENSURE(tray_move, CDC_CLOSE_TRAY | CDC_OPEN_TRAY);
	ENSURE(lock_door, CDC_LOCK);
	ENSURE(select_speed, CDC_SELECT_SPEED);
	ENSURE(get_last_session, CDC_MULTI_SESSION);
	ENSURE(get_mcn, CDC_MCN);
	ENSURE(reset, CDC_RESET);
	ENSURE(audio_ioctl, CDC_PLAY_AUDIO);
	ENSURE(generic_packet, CDC_GENERIC_PACKET);
	cdi->mc_flags = 0;
	cdo->n_minors = 0;
        cdi->options = CDO_USE_FFLAGS;
	
	if (autoclose==1 && CDROM_CAN(CDC_CLOSE_TRAY))
		cdi->options |= (int) CDO_AUTO_CLOSE;
	if (autoeject==1 && CDROM_CAN(CDC_OPEN_TRAY))
		cdi->options |= (int) CDO_AUTO_EJECT;
	if (lockdoor==1)
		cdi->options |= (int) CDO_LOCK;
	if (check_media_type==1)
		cdi->options |= (int) CDO_CHECK_TYPE;

	if (CDROM_CAN(CDC_MRW_W))
		cdi->exit = cdrom_mrw_exit;

	if (cdi->disk)
		cdi->cdda_method = CDDA_BPC_FULL;
	else
		cdi->cdda_method = CDDA_OLD;

	if (!cdo->generic_packet)
		cdo->generic_packet = cdrom_dummy_generic_packet;

	cdinfo(CD_REG_UNREG, "drive \"/dev/%s\" registered\n", cdi->name);
	spin_lock(&cdrom_lock);
	cdi->next = topCdromPtr; 	
	topCdromPtr = cdi;
	spin_unlock(&cdrom_lock);
	return 0;
}
#undef ENSURE

int unregister_cdrom(struct cdrom_device_info *unreg)
{
	struct cdrom_device_info *cdi, *prev;
	cdinfo(CD_OPEN, "entering unregister_cdrom\n"); 

	prev = NULL;
	spin_lock(&cdrom_lock);
	cdi = topCdromPtr;
	while (cdi && cdi != unreg) {
		prev = cdi;
		cdi = cdi->next;
	}

	if (cdi == NULL) {
		spin_unlock(&cdrom_lock);
		return -2;
	}
	if (prev)
		prev->next = cdi->next;
	else
		topCdromPtr = cdi->next;

	spin_unlock(&cdrom_lock);

	if (cdi->exit)
		cdi->exit(cdi);

	cdi->ops->n_minors--;
	cdinfo(CD_REG_UNREG, "drive \"/dev/%s\" unregistered\n", cdi->name);
	return 0;
}

int cdrom_get_media_event(struct cdrom_device_info *cdi,
			  struct media_event_desc *med)
{
	struct packet_command cgc;
	unsigned char buffer[8];
	struct event_header *eh = (struct event_header *) buffer;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_GET_EVENT_STATUS_NOTIFICATION;
	cgc.cmd[1] = 1;		/* IMMED */
	cgc.cmd[4] = 1 << 4;	/* media event */
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

	if (cdi->ops->generic_packet(cdi, &cgc))
		return 1;

	if (be16_to_cpu(eh->data_len) < sizeof(*med))
		return 1;

	if (eh->nea || eh->notification_class != 0x4)
		return 1;

	memcpy(med, &buffer[sizeof(*eh)], sizeof(*med));
	return 0;
}

/*
 * the first prototypes used 0x2c as the page code for the mrw mode page,
 * subsequently this was changed to 0x03. probe the one used by this drive
 */
static int cdrom_mrw_probe_pc(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[16];

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.timeout = HZ;
	cgc.quiet = 1;

	if (!cdrom_mode_sense(cdi, &cgc, MRW_MODE_PC, 0)) {
		cdi->mrw_mode_page = MRW_MODE_PC;
		return 0;
	} else if (!cdrom_mode_sense(cdi, &cgc, MRW_MODE_PC_PRE1, 0)) {
		cdi->mrw_mode_page = MRW_MODE_PC_PRE1;
		return 0;
	}

	return 1;
}

static int cdrom_is_mrw(struct cdrom_device_info *cdi, int *write)
{
	struct packet_command cgc;
	struct mrw_feature_desc *mfd;
	unsigned char buffer[16];
	int ret;

	*write = 0;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[3] = CDF_MRW;
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

	if ((ret = cdi->ops->generic_packet(cdi, &cgc)))
		return ret;

	mfd = (struct mrw_feature_desc *)&buffer[sizeof(struct feature_header)];
	if (be16_to_cpu(mfd->feature_code) != CDF_MRW)
		return 1;
	*write = mfd->write;

	if ((ret = cdrom_mrw_probe_pc(cdi))) {
		*write = 0;
		return ret;
	}

	return 0;
}

static int cdrom_mrw_bgformat(struct cdrom_device_info *cdi, int cont)
{
	struct packet_command cgc;
	unsigned char buffer[12];
	int ret;

	printk(KERN_INFO "cdrom: %sstarting format\n", cont ? "Re" : "");

	/*
	 * FmtData bit set (bit 4), format type is 1
	 */
	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_WRITE);
	cgc.cmd[0] = GPCMD_FORMAT_UNIT;
	cgc.cmd[1] = (1 << 4) | 1;

	cgc.timeout = 5 * 60 * HZ;

	/*
	 * 4 byte format list header, 8 byte format list descriptor
	 */
	buffer[1] = 1 << 1;
	buffer[3] = 8;

	/*
	 * nr_blocks field
	 */
	buffer[4] = 0xff;
	buffer[5] = 0xff;
	buffer[6] = 0xff;
	buffer[7] = 0xff;

	buffer[8] = 0x24 << 2;
	buffer[11] = cont;

	ret = cdi->ops->generic_packet(cdi, &cgc);
	if (ret)
		printk(KERN_INFO "cdrom: bgformat failed\n");

	return ret;
}

static int cdrom_mrw_bgformat_susp(struct cdrom_device_info *cdi, int immed)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_CLOSE_TRACK;

	/*
	 * Session = 1, Track = 0
	 */
	cgc.cmd[1] = !!immed;
	cgc.cmd[2] = 1 << 1;

	cgc.timeout = 5 * 60 * HZ;

	return cdi->ops->generic_packet(cdi, &cgc);
}

static int cdrom_flush_cache(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_FLUSH_CACHE;

	cgc.timeout = 5 * 60 * HZ;

	return cdi->ops->generic_packet(cdi, &cgc);
}

static int cdrom_mrw_exit(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < (int)offsetof(typeof(di),disc_type))
		return 1;

	ret = 0;
	if (di.mrw_status == CDM_MRW_BGFORMAT_ACTIVE) {
		printk(KERN_INFO "cdrom: issuing MRW back ground "
				"format suspend\n");
		ret = cdrom_mrw_bgformat_susp(cdi, 0);
	}

	if (!ret && cdi->media_written)
		ret = cdrom_flush_cache(cdi);

	return ret;
}

static int cdrom_mrw_set_lba_space(struct cdrom_device_info *cdi, int space)
{
	struct packet_command cgc;
	struct mode_page_header *mph;
	char buffer[16];
	int ret, offset, size;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.buffer = buffer;
	cgc.buflen = sizeof(buffer);

	if ((ret = cdrom_mode_sense(cdi, &cgc, cdi->mrw_mode_page, 0)))
		return ret;

	mph = (struct mode_page_header *) buffer;
	offset = be16_to_cpu(mph->desc_length);
	size = be16_to_cpu(mph->mode_data_length) + 2;

	buffer[offset + 3] = space;
	cgc.buflen = size;

	if ((ret = cdrom_mode_select(cdi, &cgc)))
		return ret;

	printk(KERN_INFO "cdrom: %s: mrw address space %s selected\n", cdi->name, mrw_address_space[space]);
	return 0;
}

static int cdrom_get_random_writable(struct cdrom_device_info *cdi,
			      struct rwrt_feature_desc *rfd)
{
	struct packet_command cgc;
	char buffer[24];
	int ret;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;	/* often 0x46 */
	cgc.cmd[3] = CDF_RWRT;			/* often 0x0020 */
	cgc.cmd[8] = sizeof(buffer);		/* often 0x18 */
	cgc.quiet = 1;

	if ((ret = cdi->ops->generic_packet(cdi, &cgc)))
		return ret;

	memcpy(rfd, &buffer[sizeof(struct feature_header)], sizeof (*rfd));
	return 0;
}

static int cdrom_has_defect_mgt(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[16];
	__u16 *feature_code;
	int ret;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[3] = CDF_HWDM;
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

	if ((ret = cdi->ops->generic_packet(cdi, &cgc)))
		return ret;

	feature_code = (__u16 *) &buffer[sizeof(struct feature_header)];
	if (be16_to_cpu(*feature_code) == CDF_HWDM)
		return 0;

	return 1;
}


static int cdrom_is_random_writable(struct cdrom_device_info *cdi, int *write)
{
	struct rwrt_feature_desc rfd;
	int ret;

	*write = 0;

	if ((ret = cdrom_get_random_writable(cdi, &rfd)))
		return ret;

	if (CDF_RWRT == be16_to_cpu(rfd.feature_code))
		*write = 1;

	return 0;
}

static int cdrom_media_erasable(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < offsetof(typeof(di), n_first_track))
		return -1;

	return di.erasable;
}

/*
 * FIXME: check RO bit
 */
static int cdrom_dvdram_open_write(struct cdrom_device_info *cdi)
{
	int ret = cdrom_media_erasable(cdi);

	/*
	 * allow writable open if media info read worked and media is
	 * erasable, _or_ if it fails since not all drives support it
	 */
	if (!ret)
		return 1;

	return 0;
}

static int cdrom_mrw_open_write(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	/*
	 * always reset to DMA lba space on open
	 */
	if (cdrom_mrw_set_lba_space(cdi, MRW_LBA_DMA)) {
		printk(KERN_ERR "cdrom: failed setting lba address space\n");
		return 1;
	}

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < offsetof(typeof(di),disc_type))
		return 1;

	if (!di.erasable)
		return 1;

	/*
	 * mrw_status
	 * 0	-	not MRW formatted
	 * 1	-	MRW bgformat started, but not running or complete
	 * 2	-	MRW bgformat in progress
	 * 3	-	MRW formatting complete
	 */
	ret = 0;
	printk(KERN_INFO "cdrom open: mrw_status '%s'\n",
			mrw_format_status[di.mrw_status]);
	if (!di.mrw_status)
		ret = 1;
	else if (di.mrw_status == CDM_MRW_BGFORMAT_INACTIVE &&
			mrw_format_restart)
		ret = cdrom_mrw_bgformat(cdi, 1);

	return ret;
}

static int mo_open_write(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[255];
	int ret;

	init_cdrom_command(&cgc, &buffer, 4, CGC_DATA_READ);
	cgc.quiet = 1;

	/*
	 * obtain write protect information as per
	 * drivers/scsi/sd.c:sd_read_write_protect_flag
	 */

	ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
	if (ret)
		ret = cdrom_mode_sense(cdi, &cgc, GPMODE_VENDOR_PAGE, 0);
	if (ret) {
		cgc.buflen = 255;
		ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
	}

	/* drive gave us no info, let the user go ahead */
	if (ret)
		return 0;

	return buffer[3] & 0x80;
}

static int cdrom_ram_open_write(struct cdrom_device_info *cdi)
{
	struct rwrt_feature_desc rfd;
	int ret;

	if ((ret = cdrom_has_defect_mgt(cdi)))
		return ret;

	if ((ret = cdrom_get_random_writable(cdi, &rfd)))
		return ret;
	else if (CDF_RWRT == be16_to_cpu(rfd.feature_code))
		ret = !rfd.curr;

	cdinfo(CD_OPEN, "can open for random write\n");
	return ret;
}

static void cdrom_mmc3_profile(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[32];
	int ret, mmc3_profile;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[1] = 0;
	cgc.cmd[2] = cgc.cmd[3] = 0;		/* Starting Feature Number */
	cgc.cmd[8] = sizeof(buffer);		/* Allocation Length */
	cgc.quiet = 1;

	if ((ret = cdi->ops->generic_packet(cdi, &cgc)))
		mmc3_profile = 0xffff;
	else
		mmc3_profile = (buffer[6] << 8) | buffer[7];

	cdi->mmc3_profile = mmc3_profile;
}

static int cdrom_is_dvd_rw(struct cdrom_device_info *cdi)
{
	switch (cdi->mmc3_profile) {
	case 0x12:	/* DVD-RAM	*/
	case 0x1A:	/* DVD+RW	*/
		return 0;
	default:
		return 1;
	}
}

/*
 * returns 0 for ok to open write, non-0 to disallow
 */
static int cdrom_open_write(struct cdrom_device_info *cdi)
{
	int mrw, mrw_write, ram_write;
	int ret = 1;

	mrw = 0;
	if (!cdrom_is_mrw(cdi, &mrw_write))
		mrw = 1;

	if (CDROM_CAN(CDC_MO_DRIVE))
		ram_write = 1;
	else
		(void) cdrom_is_random_writable(cdi, &ram_write);
	
	if (mrw)
		cdi->mask &= ~CDC_MRW;
	else
		cdi->mask |= CDC_MRW;

	if (mrw_write)
		cdi->mask &= ~CDC_MRW_W;
	else
		cdi->mask |= CDC_MRW_W;

	if (ram_write)
		cdi->mask &= ~CDC_RAM;
	else
		cdi->mask |= CDC_RAM;

	if (CDROM_CAN(CDC_MRW_W))
		ret = cdrom_mrw_open_write(cdi);
	else if (CDROM_CAN(CDC_DVD_RAM))
		ret = cdrom_dvdram_open_write(cdi);
 	else if (CDROM_CAN(CDC_RAM) &&
 		 !CDROM_CAN(CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_MRW|CDC_MO_DRIVE))
 		ret = cdrom_ram_open_write(cdi);
	else if (CDROM_CAN(CDC_MO_DRIVE))
		ret = mo_open_write(cdi);
	else if (!cdrom_is_dvd_rw(cdi))
		ret = 0;

	return ret;
}

static void cdrom_dvd_rw_close_write(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;

	if (cdi->mmc3_profile != 0x1a) {
		cdinfo(CD_CLOSE, "%s: No DVD+RW\n", cdi->name);
		return;
	}

	if (!cdi->media_written) {
		cdinfo(CD_CLOSE, "%s: DVD+RW media clean\n", cdi->name);
		return;
	}

	printk(KERN_INFO "cdrom: %s: dirty DVD+RW media, \"finalizing\"\n",
	       cdi->name);

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
	cgc.timeout = 30*HZ;
	cdi->ops->generic_packet(cdi, &cgc);

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_CLOSE_TRACK;
	cgc.timeout = 3000*HZ;
	cgc.quiet = 1;
	cdi->ops->generic_packet(cdi, &cgc);

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_CLOSE_TRACK;
	cgc.cmd[2] = 2;	 /* Close session */
	cgc.quiet = 1;
	cgc.timeout = 3000*HZ;
	cdi->ops->generic_packet(cdi, &cgc);

	cdi->media_written = 0;
}

static int cdrom_close_write(struct cdrom_device_info *cdi)
{
#if 0
	return cdrom_flush_cache(cdi);
#else
	return 0;
#endif
}

/* We use the open-option O_NONBLOCK to indicate that the
 * purpose of opening is only for subsequent ioctl() calls; no device
 * integrity checks are performed.
 *
 * We hope that all cd-player programs will adopt this convention. It
 * is in their own interest: device control becomes a lot easier
 * this way.
 */
int cdrom_open(struct cdrom_device_info *cdi, struct inode *ip, struct file *fp)
{
	int ret;

	cdinfo(CD_OPEN, "entering cdrom_open\n"); 

	/* if this was a O_NONBLOCK open and we should honor the flags,
	 * do a quick open without drive/disc integrity checks. */
	cdi->use_count++;
	if ((fp->f_flags & O_NONBLOCK) && (cdi->options & CDO_USE_FFLAGS)) {
		ret = cdi->ops->open(cdi, 1);
	} else {
		ret = open_for_data(cdi);
		if (ret)
			goto err;
		cdrom_mmc3_profile(cdi);
		if (fp->f_mode & FMODE_WRITE) {
			ret = -EROFS;
			if (cdrom_open_write(cdi))
				goto err_release;
			if (!CDROM_CAN(CDC_RAM))
				goto err_release;
			ret = 0;
			cdi->media_written = 0;
		}
	}

	if (ret)
		goto err;

	cdinfo(CD_OPEN, "Use count for \"/dev/%s\" now %d\n",
			cdi->name, cdi->use_count);
	/* Do this on open.  Don't wait for mount, because they might
	    not be mounting, but opening with O_NONBLOCK */
	check_disk_change(ip->i_bdev);
	return 0;
err_release:
	cdi->ops->release(cdi);
err:
	cdi->use_count--;
	return ret;
}

static
int open_for_data(struct cdrom_device_info * cdi)
{
	int ret;
	struct cdrom_device_ops *cdo = cdi->ops;
	tracktype tracks;
	cdinfo(CD_OPEN, "entering open_for_data\n");
	/* Check if the driver can report drive status.  If it can, we
	   can do clever things.  If it can't, well, we at least tried! */
	if (cdo->drive_status != NULL) {
		ret = cdo->drive_status(cdi, CDSL_CURRENT);
		cdinfo(CD_OPEN, "drive_status=%d\n", ret); 
		if (ret == CDS_TRAY_OPEN) {
			cdinfo(CD_OPEN, "the tray is open...\n"); 
			/* can/may i close it? */
			if (CDROM_CAN(CDC_CLOSE_TRAY) &&
			    cdi->options & CDO_AUTO_CLOSE) {
				cdinfo(CD_OPEN, "trying to close the tray.\n"); 
				ret=cdo->tray_move(cdi,0);
				if (ret) {
					cdinfo(CD_OPEN, "bummer. tried to close the tray but failed.\n"); 
					/* Ignore the error from the low
					level driver.  We don't care why it
					couldn't close the tray.  We only care 
					that there is no disc in the drive, 
					since that is the _REAL_ problem here.*/
					ret=-ENOMEDIUM;
					goto clean_up_and_return;
				}
			} else {
				cdinfo(CD_OPEN, "bummer. this drive can't close the tray.\n"); 
				ret=-ENOMEDIUM;
				goto clean_up_and_return;
			}
			/* Ok, the door should be closed now.. Check again */
			ret = cdo->drive_status(cdi, CDSL_CURRENT);
			if ((ret == CDS_NO_DISC) || (ret==CDS_TRAY_OPEN)) {
				cdinfo(CD_OPEN, "bummer. the tray is still not closed.\n"); 
				cdinfo(CD_OPEN, "tray might not contain a medium.\n");
				ret=-ENOMEDIUM;
				goto clean_up_and_return;
			}
			cdinfo(CD_OPEN, "the tray is now closed.\n"); 
		}
		/* the door should be closed now, check for the disc */
		ret = cdo->drive_status(cdi, CDSL_CURRENT);
		if (ret!=CDS_DISC_OK) {
			ret = -ENOMEDIUM;
			goto clean_up_and_return;
		}
	}
	cdrom_count_tracks(cdi, &tracks);
	if (tracks.error == CDS_NO_DISC) {
		cdinfo(CD_OPEN, "bummer. no disc.\n");
		ret=-ENOMEDIUM;
		goto clean_up_and_return;
	}
	/* CD-Players which don't use O_NONBLOCK, workman
	 * for example, need bit CDO_CHECK_TYPE cleared! */
	if (tracks.data==0) {
		if (cdi->options & CDO_CHECK_TYPE) {
		    /* give people a warning shot, now that CDO_CHECK_TYPE
		       is the default case! */
		    cdinfo(CD_OPEN, "bummer. wrong media type.\n"); 
		    cdinfo(CD_WARNING, "pid %d must open device O_NONBLOCK!\n",
					(unsigned int)current->pid); 
		    ret=-EMEDIUMTYPE;
		    goto clean_up_and_return;
		}
		else {
		    cdinfo(CD_OPEN, "wrong media type, but CDO_CHECK_TYPE not set.\n");
		}
	}

	cdinfo(CD_OPEN, "all seems well, opening the device.\n"); 

	/* all seems well, we can open the device */
	ret = cdo->open(cdi, 0); /* open for data */
	cdinfo(CD_OPEN, "opening the device gave me %d.\n", ret); 
	/* After all this careful checking, we shouldn't have problems
	   opening the device, but we don't want the device locked if 
	   this somehow fails... */
	if (ret) {
		cdinfo(CD_OPEN, "open device failed.\n"); 
		goto clean_up_and_return;
	}
	if (CDROM_CAN(CDC_LOCK) && (cdi->options & CDO_LOCK)) {
			cdo->lock_door(cdi, 1);
			cdinfo(CD_OPEN, "door locked.\n");
	}
	cdinfo(CD_OPEN, "device opened successfully.\n"); 
	return ret;

	/* Something failed.  Try to unlock the drive, because some drivers
	(notably ide-cd) lock the drive after every command.  This produced
	a nasty bug where after mount failed, the drive would remain locked!  
	This ensures that the drive gets unlocked after a mount fails.  This 
	is a goto to avoid bloating the driver with redundant code. */ 
clean_up_and_return:
	cdinfo(CD_OPEN, "open failed.\n"); 
	if (CDROM_CAN(CDC_LOCK) && cdi->options & CDO_LOCK) {
			cdo->lock_door(cdi, 0);
			cdinfo(CD_OPEN, "door unlocked.\n");
	}
	return ret;
}

/* This code is similar to that in open_for_data. The routine is called
   whenever an audio play operation is requested.
*/
int check_for_audio_disc(struct cdrom_device_info * cdi,
			 struct cdrom_device_ops * cdo)
{
        int ret;
	tracktype tracks;
	cdinfo(CD_OPEN, "entering check_for_audio_disc\n");
	if (!(cdi->options & CDO_CHECK_TYPE))
		return 0;
	if (cdo->drive_status != NULL) {
		ret = cdo->drive_status(cdi, CDSL_CURRENT);
		cdinfo(CD_OPEN, "drive_status=%d\n", ret); 
		if (ret == CDS_TRAY_OPEN) {
			cdinfo(CD_OPEN, "the tray is open...\n"); 
			/* can/may i close it? */
			if (CDROM_CAN(CDC_CLOSE_TRAY) &&
			    cdi->options & CDO_AUTO_CLOSE) {
				cdinfo(CD_OPEN, "trying to close the tray.\n"); 
				ret=cdo->tray_move(cdi,0);
				if (ret) {
					cdinfo(CD_OPEN, "bummer. tried to close tray but failed.\n"); 
					/* Ignore the error from the low
					level driver.  We don't care why it
					couldn't close the tray.  We only care 
					that there is no disc in the drive, 
					since that is the _REAL_ problem here.*/
					return -ENOMEDIUM;
				}
			} else {
				cdinfo(CD_OPEN, "bummer. this driver can't close the tray.\n"); 
				return -ENOMEDIUM;
			}
			/* Ok, the door should be closed now.. Check again */
			ret = cdo->drive_status(cdi, CDSL_CURRENT);
			if ((ret == CDS_NO_DISC) || (ret==CDS_TRAY_OPEN)) {
				cdinfo(CD_OPEN, "bummer. the tray is still not closed.\n"); 
				return -ENOMEDIUM;
			}	
			if (ret!=CDS_DISC_OK) {
				cdinfo(CD_OPEN, "bummer. disc isn't ready.\n"); 
				return -EIO;
			}	
			cdinfo(CD_OPEN, "the tray is now closed.\n"); 
		}	
	}
	cdrom_count_tracks(cdi, &tracks);
	if (tracks.error) 
		return(tracks.error);

	if (tracks.audio==0)
		return -EMEDIUMTYPE;

	return 0;
}

/* Admittedly, the logic below could be performed in a nicer way. */
int cdrom_release(struct cdrom_device_info *cdi, struct file *fp)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	int opened_for_data;

	cdinfo(CD_CLOSE, "entering cdrom_release\n"); 

	if (cdi->use_count > 0)
		cdi->use_count--;
	if (cdi->use_count == 0)
		cdinfo(CD_CLOSE, "Use count for \"/dev/%s\" now zero\n", cdi->name);
	if (cdi->use_count == 0)
		cdrom_dvd_rw_close_write(cdi);
	if (cdi->use_count == 0 &&
	    (cdo->capability & CDC_LOCK) && !keeplocked) {
		cdinfo(CD_CLOSE, "Unlocking door!\n");
		cdo->lock_door(cdi, 0);
	}
	opened_for_data = !(cdi->options & CDO_USE_FFLAGS) ||
		!(fp && fp->f_flags & O_NONBLOCK);

	/*
	 * flush cache on last write release
	 */
	if (CDROM_CAN(CDC_RAM) && !cdi->use_count && cdi->for_data)
		cdrom_close_write(cdi);

	cdo->release(cdi);
	if (cdi->use_count == 0) {      /* last process that closes dev*/
		if (opened_for_data &&
		    cdi->options & CDO_AUTO_EJECT && CDROM_CAN(CDC_OPEN_TRAY))
			cdo->tray_move(cdi, 1);
	}
	return 0;
}

static int cdrom_read_mech_status(struct cdrom_device_info *cdi, 
				  struct cdrom_changer_info *buf)
{
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;
	int length;

	/*
	 * Sanyo changer isn't spec compliant (doesn't use regular change
	 * LOAD_UNLOAD command, and it doesn't implement the mech status
	 * command below
	 */
	if (cdi->sanyo_slot) {
		buf->hdr.nslots = 3;
		buf->hdr.curslot = cdi->sanyo_slot == 3 ? 0 : cdi->sanyo_slot;
		for (length = 0; length < 3; length++) {
			buf->slots[length].disc_present = 1;
			buf->slots[length].change = 0;
		}
		return 0;
	}

	length = sizeof(struct cdrom_mechstat_header) +
		 cdi->capacity * sizeof(struct cdrom_slot);

	init_cdrom_command(&cgc, buf, length, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_MECHANISM_STATUS;
	cgc.cmd[8] = (length >> 8) & 0xff;
	cgc.cmd[9] = length & 0xff;
	return cdo->generic_packet(cdi, &cgc);
}

static int cdrom_slot_status(struct cdrom_device_info *cdi, int slot)
{
	struct cdrom_changer_info *info;
	int ret;

	cdinfo(CD_CHANGER, "entering cdrom_slot_status()\n"); 
	if (cdi->sanyo_slot)
		return CDS_NO_INFO;
	
	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	if ((ret = cdrom_read_mech_status(cdi, info)))
		goto out_free;

	if (info->slots[slot].disc_present)
		ret = CDS_DISC_OK;
	else
		ret = CDS_NO_DISC;

out_free:
	kfree(info);
	return ret;
}

/* Return the number of slots for an ATAPI/SCSI cdrom, 
 * return 1 if not a changer. 
 */
int cdrom_number_of_slots(struct cdrom_device_info *cdi) 
{
	int status;
	int nslots = 1;
	struct cdrom_changer_info *info;

	cdinfo(CD_CHANGER, "entering cdrom_number_of_slots()\n"); 
	/* cdrom_read_mech_status requires a valid value for capacity: */
	cdi->capacity = 0; 

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	if ((status = cdrom_read_mech_status(cdi, info)) == 0)
		nslots = info->hdr.nslots;

	kfree(info);
	return nslots;
}


/* If SLOT < 0, unload the current slot.  Otherwise, try to load SLOT. */
static int cdrom_load_unload(struct cdrom_device_info *cdi, int slot) 
{
	struct packet_command cgc;

	cdinfo(CD_CHANGER, "entering cdrom_load_unload()\n"); 
	if (cdi->sanyo_slot && slot < 0)
		return 0;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_LOAD_UNLOAD;
	cgc.cmd[4] = 2 + (slot >= 0);
	cgc.cmd[8] = slot;
	cgc.timeout = 60 * HZ;

	/* The Sanyo 3 CD changer uses byte 7 of the 
	GPCMD_TEST_UNIT_READY to command to switch CDs instead of
	using the GPCMD_LOAD_UNLOAD opcode. */
	if (cdi->sanyo_slot && -1 < slot) {
		cgc.cmd[0] = GPCMD_TEST_UNIT_READY;
		cgc.cmd[7] = slot;
		cgc.cmd[4] = cgc.cmd[8] = 0;
		cdi->sanyo_slot = slot ? slot : 3;
	}

	return cdi->ops->generic_packet(cdi, &cgc);
}

static int cdrom_select_disc(struct cdrom_device_info *cdi, int slot)
{
	struct cdrom_changer_info *info;
	int curslot;
	int ret;

	cdinfo(CD_CHANGER, "entering cdrom_select_disc()\n"); 
	if (!CDROM_CAN(CDC_SELECT_DISC))
		return -EDRIVE_CANT_DO_THIS;

	(void) cdi->ops->media_changed(cdi, slot);

	if (slot == CDSL_NONE) {
		/* set media changed bits, on both queues */
		cdi->mc_flags = 0x3;
		return cdrom_load_unload(cdi, -1);
	}

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	if ((ret = cdrom_read_mech_status(cdi, info))) {
		kfree(info);
		return ret;
	}

	curslot = info->hdr.curslot;
	kfree(info);

	if (cdi->use_count > 1 || keeplocked) {
		if (slot == CDSL_CURRENT) {
	    		return curslot;
		} else {
			return -EBUSY;
		}
	}

	/* Specifying CDSL_CURRENT will attempt to load the currnet slot,
	which is useful if it had been previously unloaded.
	Whether it can or not, it returns the current slot. 
	Similarly,  if slot happens to be the current one, we still
	try and load it. */
	if (slot == CDSL_CURRENT)
		slot = curslot;

	/* set media changed bits on both queues */
	cdi->mc_flags = 0x3;
	if ((ret = cdrom_load_unload(cdi, slot)))
		return ret;

	return slot;
}

/* We want to make media_changed accessible to the user through an
 * ioctl. The main problem now is that we must double-buffer the
 * low-level implementation, to assure that the VFS and the user both
 * see a medium change once.
 */

static
int media_changed(struct cdrom_device_info *cdi, int queue)
{
	unsigned int mask = (1 << (queue & 1));
	int ret = !!(cdi->mc_flags & mask);

	if (!CDROM_CAN(CDC_MEDIA_CHANGED))
	    return ret;
	/* changed since last call? */
	if (cdi->ops->media_changed(cdi, CDSL_CURRENT)) {
		cdi->mc_flags = 0x3;    /* set bit on both queues */
		ret |= 1;
		cdi->media_written = 0;
	}
	cdi->mc_flags &= ~mask;         /* clear bit */
	return ret;
}

int cdrom_media_changed(struct cdrom_device_info *cdi)
{
	/* This talks to the VFS, which doesn't like errors - just 1 or 0.  
	 * Returning "0" is always safe (media hasn't been changed). Do that 
	 * if the low-level cdrom driver dosn't support media changed. */ 
	if (cdi == NULL || cdi->ops->media_changed == NULL)
		return 0;
	if (!CDROM_CAN(CDC_MEDIA_CHANGED))
		return 0;
	return media_changed(cdi, 0);
}

/* badly broken, I know. Is due for a fixup anytime. */
static void cdrom_count_tracks(struct cdrom_device_info *cdi, tracktype* tracks)
{
	struct cdrom_tochdr header;
	struct cdrom_tocentry entry;
	int ret, i;
	tracks->data=0;
	tracks->audio=0;
	tracks->cdi=0;
	tracks->xa=0;
	tracks->error=0;
	cdinfo(CD_COUNT_TRACKS, "entering cdrom_count_tracks\n"); 
        if (!CDROM_CAN(CDC_PLAY_AUDIO)) { 
                tracks->error=CDS_NO_INFO;
                return;
        }        
	/* Grab the TOC header so we can see how many tracks there are */
	if ((ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCHDR, &header))) {
		if (ret == -ENOMEDIUM)
			tracks->error = CDS_NO_DISC;
		else
			tracks->error = CDS_NO_INFO;
		return;
	}	
	/* check what type of tracks are on this disc */
	entry.cdte_format = CDROM_MSF;
	for (i = header.cdth_trk0; i <= header.cdth_trk1; i++) {
		entry.cdte_track  = i;
		if (cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, &entry)) {
			tracks->error=CDS_NO_INFO;
			return;
		}	
		if (entry.cdte_ctrl & CDROM_DATA_TRACK) {
		    if (entry.cdte_format == 0x10)
			tracks->cdi++;
		    else if (entry.cdte_format == 0x20) 
			tracks->xa++;
		    else
			tracks->data++;
		} else
		    tracks->audio++;
		cdinfo(CD_COUNT_TRACKS, "track %d: format=%d, ctrl=%d\n",
		       i, entry.cdte_format, entry.cdte_ctrl);
	}	
	cdinfo(CD_COUNT_TRACKS, "disc has %d tracks: %d=audio %d=data %d=Cd-I %d=XA\n", 
		header.cdth_trk1, tracks->audio, tracks->data, 
		tracks->cdi, tracks->xa);
}	

/* Requests to the low-level drivers will /always/ be done in the
   following format convention:

   CDROM_LBA: all data-related requests.
   CDROM_MSF: all audio-related requests.

   However, a low-level implementation is allowed to refuse this
   request, and return information in its own favorite format.

   It doesn't make sense /at all/ to ask for a play_audio in LBA
   format, or ask for multi-session info in MSF format. However, for
   backward compatibility these format requests will be satisfied, but
   the requests to the low-level drivers will be sanitized in the more
   meaningful format indicated above.
 */

static
void sanitize_format(union cdrom_addr *addr,
		     u_char * curr, u_char requested)
{
	if (*curr == requested)
		return;                 /* nothing to be done! */
	if (requested == CDROM_LBA) {
		addr->lba = (int) addr->msf.frame +
			75 * (addr->msf.second - 2 + 60 * addr->msf.minute);
	} else {                        /* CDROM_MSF */
		int lba = addr->lba;
		addr->msf.frame = lba % 75;
		lba /= 75;
		lba += 2;
		addr->msf.second = lba % 60;
		addr->msf.minute = lba / 60;
	}
	*curr = requested;
}

void init_cdrom_command(struct packet_command *cgc, void *buf, int len,
			int type)
{
	memset(cgc, 0, sizeof(struct packet_command));
	if (buf)
		memset(buf, 0, len);
	cgc->buffer = (char *) buf;
	cgc->buflen = len;
	cgc->data_direction = type;
	cgc->timeout = 5*HZ;
}

/* DVD handling */

#define copy_key(dest,src)	memcpy((dest), (src), sizeof(dvd_key))
#define copy_chal(dest,src)	memcpy((dest), (src), sizeof(dvd_challenge))

static void setup_report_key(struct packet_command *cgc, unsigned agid, unsigned type)
{
	cgc->cmd[0] = GPCMD_REPORT_KEY;
	cgc->cmd[10] = type | (agid << 6);
	switch (type) {
		case 0: case 8: case 5: {
			cgc->buflen = 8;
			break;
		}
		case 1: {
			cgc->buflen = 16;
			break;
		}
		case 2: case 4: {
			cgc->buflen = 12;
			break;
		}
	}
	cgc->cmd[9] = cgc->buflen;
	cgc->data_direction = CGC_DATA_READ;
}

static void setup_send_key(struct packet_command *cgc, unsigned agid, unsigned type)
{
	cgc->cmd[0] = GPCMD_SEND_KEY;
	cgc->cmd[10] = type | (agid << 6);
	switch (type) {
		case 1: {
			cgc->buflen = 16;
			break;
		}
		case 3: {
			cgc->buflen = 12;
			break;
		}
		case 6: {
			cgc->buflen = 8;
			break;
		}
	}
	cgc->cmd[9] = cgc->buflen;
	cgc->data_direction = CGC_DATA_WRITE;
}

static int dvd_do_auth(struct cdrom_device_info *cdi, dvd_authinfo *ai)
{
	int ret;
	u_char buf[20];
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;
	rpc_state_t rpc_state;

	memset(buf, 0, sizeof(buf));
	init_cdrom_command(&cgc, buf, 0, CGC_DATA_READ);

	switch (ai->type) {
	/* LU data send */
	case DVD_LU_SEND_AGID:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_AGID\n"); 
		cgc.quiet = 1;
		setup_report_key(&cgc, ai->lsa.agid, 0);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lsa.agid = buf[7] >> 6;
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_KEY1:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_KEY1\n"); 
		setup_report_key(&cgc, ai->lsk.agid, 2);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		copy_key(ai->lsk.key, &buf[4]);
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_CHALLENGE:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_CHALLENGE\n"); 
		setup_report_key(&cgc, ai->lsc.agid, 1);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		copy_chal(ai->lsc.chal, &buf[4]);
		/* Returning data, let host change state */
		break;

	/* Post-auth key */
	case DVD_LU_SEND_TITLE_KEY:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_TITLE_KEY\n"); 
		cgc.quiet = 1;
		setup_report_key(&cgc, ai->lstk.agid, 4);
		cgc.cmd[5] = ai->lstk.lba;
		cgc.cmd[4] = ai->lstk.lba >> 8;
		cgc.cmd[3] = ai->lstk.lba >> 16;
		cgc.cmd[2] = ai->lstk.lba >> 24;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lstk.cpm = (buf[4] >> 7) & 1;
		ai->lstk.cp_sec = (buf[4] >> 6) & 1;
		ai->lstk.cgms = (buf[4] >> 4) & 3;
		copy_key(ai->lstk.title_key, &buf[5]);
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_ASF:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_ASF\n"); 
		setup_report_key(&cgc, ai->lsasf.agid, 5);
		
		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lsasf.asf = buf[7] & 1;
		break;

	/* LU data receive (LU changes state) */
	case DVD_HOST_SEND_CHALLENGE:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_CHALLENGE\n"); 
		setup_send_key(&cgc, ai->hsc.agid, 1);
		buf[1] = 0xe;
		copy_chal(&buf[4], ai->hsc.chal);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->type = DVD_LU_SEND_KEY1;
		break;

	case DVD_HOST_SEND_KEY2:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_KEY2\n"); 
		setup_send_key(&cgc, ai->hsk.agid, 3);
		buf[1] = 0xa;
		copy_key(&buf[4], ai->hsk.key);

		if ((ret = cdo->generic_packet(cdi, &cgc))) {
			ai->type = DVD_AUTH_FAILURE;
			return ret;
		}
		ai->type = DVD_AUTH_ESTABLISHED;
		break;

	/* Misc */
	case DVD_INVALIDATE_AGID:
		cgc.quiet = 1;
		cdinfo(CD_DVD, "entering DVD_INVALIDATE_AGID\n"); 
		setup_report_key(&cgc, ai->lsa.agid, 0x3f);
		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;
		break;

	/* Get region settings */
	case DVD_LU_SEND_RPC_STATE:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_RPC_STATE\n");
		setup_report_key(&cgc, 0, 8);
		memset(&rpc_state, 0, sizeof(rpc_state_t));
		cgc.buffer = (char *) &rpc_state;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lrpcs.type = rpc_state.type_code;
		ai->lrpcs.vra = rpc_state.vra;
		ai->lrpcs.ucca = rpc_state.ucca;
		ai->lrpcs.region_mask = rpc_state.region_mask;
		ai->lrpcs.rpc_scheme = rpc_state.rpc_scheme;
		break;

	/* Set region settings */
	case DVD_HOST_SEND_RPC_STATE:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_RPC_STATE\n");
		setup_send_key(&cgc, 0, 6);
		buf[1] = 6;
		buf[4] = ai->hrpcs.pdrc;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;
		break;

	default:
		cdinfo(CD_WARNING, "Invalid DVD key ioctl (%d)\n", ai->type);
		return -ENOTTY;
	}

	return 0;
}

static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s)
{
	unsigned char buf[21], *base;
	struct dvd_layer *layer;
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;
	int ret, layer_num = s->physical.layer_num;

	if (layer_num >= DVD_LAYERS)
		return -EINVAL;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[6] = layer_num;
	cgc.cmd[7] = s->type;
	cgc.cmd[9] = cgc.buflen & 0xff;

	/*
	 * refrain from reporting errors on non-existing layers (mainly)
	 */
	cgc.quiet = 1;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	base = &buf[4];
	layer = &s->physical.layer[layer_num];

	/*
	 * place the data... really ugly, but at least we won't have to
	 * worry about endianess in userspace.
	 */
	memset(layer, 0, sizeof(*layer));
	layer->book_version = base[0] & 0xf;
	layer->book_type = base[0] >> 4;
	layer->min_rate = base[1] & 0xf;
	layer->disc_size = base[1] >> 4;
	layer->layer_type = base[2] & 0xf;
	layer->track_path = (base[2] >> 4) & 1;
	layer->nlayers = (base[2] >> 5) & 3;
	layer->track_density = base[3] & 0xf;
	layer->linear_density = base[3] >> 4;
	layer->start_sector = base[5] << 16 | base[6] << 8 | base[7];
	layer->end_sector = base[9] << 16 | base[10] << 8 | base[11];
	layer->end_sector_l0 = base[13] << 16 | base[14] << 8 | base[15];
	layer->bca = base[16] >> 7;

	return 0;
}

static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret;
	u_char buf[8];
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[6] = s->copyright.layer_num;
	cgc.cmd[7] = s->type;
	cgc.cmd[8] = cgc.buflen >> 8;
	cgc.cmd[9] = cgc.buflen & 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	s->copyright.cpst = buf[4];
	s->copyright.rmi = buf[5];

	return 0;
}

static int dvd_read_disckey(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret, size;
	u_char *buf;
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	size = sizeof(s->disckey.value) + 4;

	if ((buf = (u_char *) kmalloc(size, GFP_KERNEL)) == NULL)
		return -ENOMEM;

	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[7] = s->type;
	cgc.cmd[8] = size >> 8;
	cgc.cmd[9] = size & 0xff;
	cgc.cmd[10] = s->disckey.agid << 6;

	if (!(ret = cdo->generic_packet(cdi, &cgc)))
		memcpy(s->disckey.value, &buf[4], sizeof(s->disckey.value));

	kfree(buf);
	return ret;
}

static int dvd_read_bca(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret;
	u_char buf[4 + 188];
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[7] = s->type;
	cgc.cmd[9] = cgc.buflen = 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	s->bca.len = buf[0] << 8 | buf[1];
	if (s->bca.len < 12 || s->bca.len > 188) {
		cdinfo(CD_WARNING, "Received invalid BCA length (%d)\n", s->bca.len);
		return -EIO;
	}
	memcpy(s->bca.value, &buf[4], s->bca.len);

	return 0;
}

static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret = 0, size;
	u_char *buf;
	struct packet_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	size = sizeof(s->manufact.value) + 4;

	if ((buf = (u_char *) kmalloc(size, GFP_KERNEL)) == NULL)
		return -ENOMEM;

	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[7] = s->type;
	cgc.cmd[8] = size >> 8;
	cgc.cmd[9] = size & 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc))) {
		kfree(buf);
		return ret;
	}

	s->manufact.len = buf[0] << 8 | buf[1];
	if (s->manufact.len < 0 || s->manufact.len > 2048) {
		cdinfo(CD_WARNING, "Received invalid manufacture info length"
				   " (%d)\n", s->manufact.len);
		ret = -EIO;
	} else {
		memcpy(s->manufact.value, &buf[4], s->manufact.len);
	}

	kfree(buf);
	return ret;
}

static int dvd_read_struct(struct cdrom_device_info *cdi, dvd_struct *s)
{
	switch (s->type) {
	case DVD_STRUCT_PHYSICAL:
		return dvd_read_physical(cdi, s);

	case DVD_STRUCT_COPYRIGHT:
		return dvd_read_copyright(cdi, s);

	case DVD_STRUCT_DISCKEY:
		return dvd_read_disckey(cdi, s);

	case DVD_STRUCT_BCA:
		return dvd_read_bca(cdi, s);

	case DVD_STRUCT_MANUFACT:
		return dvd_read_manufact(cdi, s);
		
	default:
		cdinfo(CD_WARNING, ": Invalid DVD structure read requested (%d)\n",
					s->type);
		return -EINVAL;
	}
}

int cdrom_mode_sense(struct cdrom_device_info *cdi,
		     struct packet_command *cgc,
		     int page_code, int page_control)
{
	struct cdrom_device_ops *cdo = cdi->ops;

	memset(cgc->cmd, 0, sizeof(cgc->cmd));

	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
	cgc->cmd[2] = page_code | (page_control << 6);
	cgc->cmd[7] = cgc->buflen >> 8;
	cgc->cmd[8] = cgc->buflen & 0xff;
	cgc->data_direction = CGC_DATA_READ;
	return cdo->generic_packet(cdi, cgc);
}

int cdrom_mode_select(struct cdrom_device_info *cdi,
		      struct packet_command *cgc)
{
	struct cdrom_device_ops *cdo = cdi->ops;

	memset(cgc->cmd, 0, sizeof(cgc->cmd));
	memset(cgc->buffer, 0, 2);
	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
	cgc->cmd[1] = 0x10;		/* PF */
	cgc->cmd[7] = cgc->buflen >> 8;
	cgc->cmd[8] = cgc->buflen & 0xff;
	cgc->data_direction = CGC_DATA_WRITE;
	return cdo->generic_packet(cdi, cgc);
}

static int cdrom_read_subchannel(struct cdrom_device_info *cdi,
				 struct cdrom_subchnl *subchnl, int mcn)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	struct packet_command cgc;
	char buffer[32];
	int ret;

	init_cdrom_command(&cgc, buffer, 16, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_SUBCHANNEL;
	cgc.cmd[1] = 2;     /* MSF addressing */
	cgc.cmd[2] = 0x40;  /* request subQ data */
	cgc.cmd[3] = mcn ? 2 : 1;
	cgc.cmd[8] = 16;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	subchnl->cdsc_audiostatus = cgc.buffer[1];
	subchnl->cdsc_format = CDROM_MSF;
	subchnl->cdsc_ctrl = cgc.buffer[5] & 0xf;
	subchnl->cdsc_trk = cgc.buffer[6];
	subchnl->cdsc_ind = cgc.buffer[7];

	subchnl->cdsc_reladdr.msf.minute = cgc.buffer[13];
	subchnl->cdsc_reladdr.msf.second = cgc.buffer[14];
	subchnl->cdsc_reladdr.msf.frame = cgc.buffer[15];
	subchnl->cdsc_absaddr.msf.minute = cgc.buffer[9];
	subchnl->cdsc_absaddr.msf.second = cgc.buffer[10];
	subchnl->cdsc_absaddr.msf.frame = cgc.buffer[11];

	return 0;
}

/*
 * Specific READ_10 interface
 */
static int cdrom_read_cd(struct cdrom_device_info *cdi,
			 struct packet_command *cgc, int lba,
			 int blocksize, int nblocks)
{
	struct cdrom_device_ops *cdo = cdi->ops;

	memset(&cgc->cmd, 0, sizeof(cgc->cmd));
	cgc->cmd[0] = GPCMD_READ_10;
	cgc->cmd[2] = (lba >> 24) & 0xff;
	cgc->cmd[3] = (lba >> 16) & 0xff;
	cgc->cmd[4] = (lba >>  8) & 0xff;
	cgc->cmd[5] = lba & 0xff;
	cgc->cmd[6] = (nblocks >> 16) & 0xff;
	cgc->cmd[7] = (nblocks >>  8) & 0xff;
	cgc->cmd[8] = nblocks & 0xff;
	cgc->buflen = blocksize * nblocks;
	return cdo->generic_packet(cdi, cgc);
}

/* very generic interface for reading the various types of blocks */
static int cdrom_read_block(struct cdrom_device_info *cdi,
			    struct packet_command *cgc,
			    int lba, int nblocks, int format, int blksize)
{
	struct cdrom_device_ops *cdo = cdi->ops;

	memset(&cgc->cmd, 0, sizeof(cgc->cmd));
	cgc->cmd[0] = GPCMD_READ_CD;
	/* expected sector size - cdda,mode1,etc. */
	cgc->cmd[1] = format << 2;
	/* starting address */
	cgc->cmd[2] = (lba >> 24) & 0xff;
	cgc->cmd[3] = (lba >> 16) & 0xff;
	cgc->cmd[4] = (lba >>  8) & 0xff;
	cgc->cmd[5] = lba & 0xff;
	/* number of blocks */
	cgc->cmd[6] = (nblocks >> 16) & 0xff;
	cgc->cmd[7] = (nblocks >>  8) & 0xff;
	cgc->cmd[8] = nblocks & 0xff;
	cgc->buflen = blksize * nblocks;
	
	/* set the header info returned */
	switch (blksize) {
	case CD_FRAMESIZE_RAW0	: cgc->cmd[9] = 0x58; break;
	case CD_FRAMESIZE_RAW1	: cgc->cmd[9] = 0x78; break;
	case CD_FRAMESIZE_RAW	: cgc->cmd[9] = 0xf8; break;
	default			: cgc->cmd[9] = 0x10;
	}
	
	return cdo->generic_packet(cdi, cgc);
}

static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf,
			       int lba, int nframes)
{
	struct packet_command cgc;
	int ret = 0;
	int nr;

	cdi->last_sense = 0;

	memset(&cgc, 0, sizeof(cgc));

	/*
	 * start with will ra.nframes size, back down if alloc fails
	 */
	nr = nframes;
	do {
		cgc.buffer = kmalloc(CD_FRAMESIZE_RAW * nr, GFP_KERNEL);
		if (cgc.buffer)
			break;

		nr >>= 1;
	} while (nr);

	if (!nr)
		return -ENOMEM;

	if (!access_ok(VERIFY_WRITE, ubuf, nframes * CD_FRAMESIZE_RAW)) {
		ret = -EFAULT;
		goto out;
	}

	cgc.data_direction = CGC_DATA_READ;
	while (nframes > 0) {
		if (nr > nframes)
			nr = nframes;

		ret = cdrom_read_block(cdi, &cgc, lba, nr, 1, CD_FRAMESIZE_RAW);
		if (ret)
			break;
		if (__copy_to_user(ubuf, cgc.buffer, CD_FRAMESIZE_RAW * nr)) {
			ret = -EFAULT;
			break;
		}
		ubuf += CD_FRAMESIZE_RAW * nr;
		nframes -= nr;
		lba += nr;
	}
out:
	kfree(cgc.buffer);
	return ret;
}

static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf,
			       int lba, int nframes)
{
	request_queue_t *q = cdi->disk->queue;
	struct request *rq;
	struct bio *bio;
	unsigned int len;
	int nr, ret = 0;

	if (!q)
		return -ENXIO;

	rq = blk_get_request(q, READ, GFP_KERNEL);
	if (!rq)
		return -ENOMEM;

	cdi->last_sense = 0;

	while (nframes) {
		nr = nframes;
		if (cdi->cdda_method == CDDA_BPC_SINGLE)
			nr = 1;
		if (nr * CD_FRAMESIZE_RAW > (q->max_sectors << 9))
			nr = (q->max_sectors << 9) / CD_FRAMESIZE_RAW;

		len = nr * CD_FRAMESIZE_RAW;

		ret = blk_rq_map_user(q, rq, ubuf, len);
		if (ret)
			break;

		memset(rq->cmd, 0, sizeof(rq->cmd));
		rq->cmd[0] = GPCMD_READ_CD;
		rq->cmd[1] = 1 << 2;
		rq->cmd[2] = (lba >> 24) & 0xff;
		rq->cmd[3] = (lba >> 16) & 0xff;
		rq->cmd[4] = (lba >>  8) & 0xff;
		rq->cmd[5] = lba & 0xff;
		rq->cmd[6] = (nr >> 16) & 0xff;
		rq->cmd[7] = (nr >>  8) & 0xff;
		rq->cmd[8] = nr & 0xff;
		rq->cmd[9] = 0xf8;

		rq->cmd_len = 12;
		rq->flags |= REQ_BLOCK_PC;
		rq->timeout = 60 * HZ;
		bio = rq->bio;

		if (rq->bio)
			blk_queue_bounce(q, &rq->bio);

		if (blk_execute_rq(q, cdi->disk, rq, 0)) {
			struct request_sense *s = rq->sense;
			ret = -EIO;
			cdi->last_sense = s->sense_key;
		}

		if (blk_rq_unmap_user(bio, len))
			ret = -EFAULT;

		if (ret)
			break;

		nframes -= nr;
		lba += nr;
		ubuf += len;
	}

	blk_put_request(rq);
	return ret;
}

static int cdrom_read_cdda(struct cdrom_device_info *cdi, __u8 __user *ubuf,
			   int lba, int nframes)
{
	int ret;

	if (cdi->cdda_method == CDDA_OLD)
		return cdrom_read_cdda_old(cdi, ubuf, lba, nframes);

retry:
	/*
	 * for anything else than success and io error, we need to retry
	 */
	ret = cdrom_read_cdda_bpc(cdi, ubuf, lba, nframes);
	if (!ret || ret != -EIO)
		return ret;

	/*
	 * I've seen drives get sense 4/8/3 udma crc errors on multi
	 * frame dma, so drop to single frame dma if we need to
	 */
	if (cdi->cdda_method == CDDA_BPC_FULL && nframes > 1) {
		printk("cdrom: dropping to single frame dma\n");
		cdi->cdda_method = CDDA_BPC_SINGLE;
		goto retry;
	}

	/*
	 * so we have an io error of some sort with multi frame dma. if the
	 * condition wasn't a hardware error
	 * problems, not for any error
	 */
	if (cdi->last_sense != 0x04 && cdi->last_sense != 0x0b)
		return ret;

	printk("cdrom: dropping to old style cdda (sense=%x)\n", cdi->last_sense);
	cdi->cdda_method = CDDA_OLD;
	return cdrom_read_cdda_old(cdi, ubuf, lba, nframes);	
}

static int cdrom_ioctl_multisession(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_multisession ms_info;
	u8 requested_format;
	int ret;

	cdinfo(CD_DO_IOCTL, "entering CDROMMULTISESSION\n");

	if (!(cdi->ops->capability & CDC_MULTI_SESSION))
		return -ENOSYS;

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

	requested_format = ms_info.addr_format;
	if (requested_format != CDROM_MSF && requested_format != CDROM_LBA)
		return -EINVAL;
	ms_info.addr_format = CDROM_LBA;

	ret = cdi->ops->get_last_session(cdi, &ms_info);
	if (ret)
		return ret;

	sanitize_format(&ms_info.addr, &ms_info.addr_format, requested_format);

	if (copy_to_user(argp, &ms_info, sizeof(ms_info)))
		return -EFAULT;

	cdinfo(CD_DO_IOCTL, "CDROMMULTISESSION successful\n");
	return 0;
}

static int cdrom_ioctl_eject(struct cdrom_device_info *cdi)
{
	cdinfo(CD_DO_IOCTL, "entering CDROMEJECT\n");

	if (!CDROM_CAN(CDC_OPEN_TRAY))
		return -ENOSYS;
	if (cdi->use_count != 1 || keeplocked)
		return -EBUSY;
	if (CDROM_CAN(CDC_LOCK)) {
		int ret = cdi->ops->lock_door(cdi, 0);
		if (ret)
			return ret;
	}

	return cdi->ops->tray_move(cdi, 1);
}

static int cdrom_ioctl_closetray(struct cdrom_device_info *cdi)
{
	cdinfo(CD_DO_IOCTL, "entering CDROMCLOSETRAY\n");

	if (!CDROM_CAN(CDC_CLOSE_TRAY))
		return -ENOSYS;
	return cdi->ops->tray_move(cdi, 0);
}

static int cdrom_ioctl_eject_sw(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROMEJECT_SW\n");

	if (!CDROM_CAN(CDC_OPEN_TRAY))
		return -ENOSYS;
	if (keeplocked)
		return -EBUSY;

	cdi->options &= ~(CDO_AUTO_CLOSE | CDO_AUTO_EJECT);
	if (arg)
		cdi->options |= CDO_AUTO_CLOSE | CDO_AUTO_EJECT;
	return 0;
}

static int cdrom_ioctl_media_changed(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	struct cdrom_changer_info *info;
	int ret;

	cdinfo(CD_DO_IOCTL, "entering CDROM_MEDIA_CHANGED\n");

	if (!CDROM_CAN(CDC_MEDIA_CHANGED))
		return -ENOSYS;

	/* cannot select disc or select current disc */
	if (!CDROM_CAN(CDC_SELECT_DISC) || arg == CDSL_CURRENT)
		return media_changed(cdi, 1);

	if ((unsigned int)arg >= cdi->capacity)
		return -EINVAL;

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	ret = cdrom_read_mech_status(cdi, info);
	if (!ret)
		ret = info->slots[arg].change;
	kfree(info);
	return ret;
}

static int cdrom_ioctl_set_options(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_SET_OPTIONS\n");

	/*
	 * Options need to be in sync with capability.
	 * Too late for that, so we have to check each one separately.
	 */
	switch (arg) {
	case CDO_USE_FFLAGS:
	case CDO_CHECK_TYPE:
		break;
	case CDO_LOCK:
		if (!CDROM_CAN(CDC_LOCK))
			return -ENOSYS;
		break;
	case 0:
		return cdi->options;
	/* default is basically CDO_[AUTO_CLOSE|AUTO_EJECT] */
	default:
		if (!CDROM_CAN(arg))
			return -ENOSYS;
	}
	cdi->options |= (int) arg;
	return cdi->options;
}

static int cdrom_ioctl_clear_options(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_CLEAR_OPTIONS\n");

	cdi->options &= ~(int) arg;
	return cdi->options;
}

static int cdrom_ioctl_select_speed(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_SELECT_SPEED\n");

	if (!CDROM_CAN(CDC_SELECT_SPEED))
		return -ENOSYS;
	return cdi->ops->select_speed(cdi, arg);
}

static int cdrom_ioctl_select_disc(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_SELECT_DISC\n");

	if (!CDROM_CAN(CDC_SELECT_DISC))
		return -ENOSYS;

	if (arg != CDSL_CURRENT && arg != CDSL_NONE) {
		if ((int)arg >= cdi->capacity)
			return -EINVAL;
	}

	/*
	 * ->select_disc is a hook to allow a driver-specific way of
	 * seleting disc.  However, since there is no equivalent hook for
	 * cdrom_slot_status this may not actually be useful...
	 */
	if (cdi->ops->select_disc)
		return cdi->ops->select_disc(cdi, arg);

	cdinfo(CD_CHANGER, "Using generic cdrom_select_disc()\n");
	return cdrom_select_disc(cdi, arg);
}

static int cdrom_ioctl_reset(struct cdrom_device_info *cdi,
		struct block_device *bdev)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_RESET\n");

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if (!CDROM_CAN(CDC_RESET))
		return -ENOSYS;
	invalidate_bdev(bdev, 0);
	return cdi->ops->reset(cdi);
}

static int cdrom_ioctl_lock_door(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "%socking door.\n", arg ? "L" : "Unl");

	if (!CDROM_CAN(CDC_LOCK))
		return -EDRIVE_CANT_DO_THIS;

	keeplocked = arg ? 1 : 0;

	/*
	 * Don't unlock the door on multiple opens by default, but allow
	 * root to do so.
	 */
	if (cdi->use_count != 1 && !arg && !capable(CAP_SYS_ADMIN))
		return -EBUSY;
	return cdi->ops->lock_door(cdi, arg);
}

static int cdrom_ioctl_debug(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "%sabling debug.\n", arg ? "En" : "Dis");

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	debug = arg ? 1 : 0;
	return debug;
}

static int cdrom_ioctl_get_capability(struct cdrom_device_info *cdi)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_GET_CAPABILITY\n");
	return (cdi->ops->capability & ~cdi->mask);
}

/*
 * The following function is implemented, although very few audio
 * discs give Universal Product Code information, which should just be
 * the Medium Catalog Number on the box.  Note, that the way the code
 * is written on the CD is /not/ uniform across all discs!
 */
static int cdrom_ioctl_get_mcn(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_mcn mcn;
	int ret;

	cdinfo(CD_DO_IOCTL, "entering CDROM_GET_MCN\n");

	if (!(cdi->ops->capability & CDC_MCN))
		return -ENOSYS;
	ret = cdi->ops->get_mcn(cdi, &mcn);
	if (ret)
		return ret;

	if (copy_to_user(argp, &mcn, sizeof(mcn)))
		return -EFAULT;
	cdinfo(CD_DO_IOCTL, "CDROM_GET_MCN successful\n");
	return 0;
}

static int cdrom_ioctl_drive_status(struct cdrom_device_info *cdi,
		unsigned long arg)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_DRIVE_STATUS\n");

	if (!(cdi->ops->capability & CDC_DRIVE_STATUS))
		return -ENOSYS;
	if (!CDROM_CAN(CDC_SELECT_DISC) ||
	    (arg == CDSL_CURRENT || arg == CDSL_NONE))
		return cdi->ops->drive_status(cdi, CDSL_CURRENT);
	if (((int)arg >= cdi->capacity))
		return -EINVAL;
	return cdrom_slot_status(cdi, arg);
}

/*
 * Ok, this is where problems start.  The current interface for the
 * CDROM_DISC_STATUS ioctl is flawed.  It makes the false assumption that
 * CDs are all CDS_DATA_1 or all CDS_AUDIO, etc.  Unfortunatly, while this
 * is often the case, it is also very common for CDs to have some tracks
 * with data, and some tracks with audio.  Just because I feel like it,
 * I declare the following to be the best way to cope.  If the CD has ANY
 * data tracks on it, it will be returned as a data CD.  If it has any XA
 * tracks, I will return it as that.  Now I could simplify this interface
 * by combining these  returns with the above, but this more clearly
 * demonstrates the problem with the current interface.  Too bad this
 * wasn't designed to use bitmasks...         -Erik
 *
 * Well, now we have the option CDS_MIXED: a mixed-type CD.
 * User level programmers might feel the ioctl is not very useful.
 *					---david
 */
static int cdrom_ioctl_disc_status(struct cdrom_device_info *cdi)
{
	tracktype tracks;

	cdinfo(CD_DO_IOCTL, "entering CDROM_DISC_STATUS\n");

	cdrom_count_tracks(cdi, &tracks);
	if (tracks.error)
		return tracks.error;

	/* Policy mode on */
	if (tracks.audio > 0) {
		if (!tracks.data && !tracks.cdi && !tracks.xa)
			return CDS_AUDIO;
		else
			return CDS_MIXED;
	}

	if (tracks.cdi > 0)
		return CDS_XA_2_2;
	if (tracks.xa > 0)
		return CDS_XA_2_1;
	if (tracks.data > 0)
		return CDS_DATA_1;
	/* Policy mode off */

	cdinfo(CD_WARNING,"This disc doesn't have any tracks I recognize!\n");
	return CDS_NO_INFO;
}

static int cdrom_ioctl_changer_nslots(struct cdrom_device_info *cdi)
{
	cdinfo(CD_DO_IOCTL, "entering CDROM_CHANGER_NSLOTS\n");
	return cdi->capacity;
}

static int cdrom_ioctl_get_subchnl(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_subchnl q;
	u8 requested, back;
	int ret;

	/* cdinfo(CD_DO_IOCTL,"entering CDROMSUBCHNL\n");*/

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&q, argp, sizeof(q)))
		return -EFAULT;

	requested = q.cdsc_format;
	if (requested != CDROM_MSF && requested != CDROM_LBA)
		return -EINVAL;
	q.cdsc_format = CDROM_MSF;

	ret = cdi->ops->audio_ioctl(cdi, CDROMSUBCHNL, &q);
	if (ret)
		return ret;

	back = q.cdsc_format; /* local copy */
	sanitize_format(&q.cdsc_absaddr, &back, requested);
	sanitize_format(&q.cdsc_reladdr, &q.cdsc_format, requested);

	if (copy_to_user(argp, &q, sizeof(q)))
		return -EFAULT;
	/* cdinfo(CD_DO_IOCTL, "CDROMSUBCHNL successful\n"); */
	return 0;
}

static int cdrom_ioctl_read_tochdr(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_tochdr header;
	int ret;

	/* cdinfo(CD_DO_IOCTL, "entering CDROMREADTOCHDR\n"); */

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&header, argp, sizeof(header)))
		return -EFAULT;

	ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCHDR, &header);
	if (ret)
		return ret;

	if (copy_to_user(argp, &header, sizeof(header)))
		return -EFAULT;
	/* cdinfo(CD_DO_IOCTL, "CDROMREADTOCHDR successful\n"); */
	return 0;
}

static int cdrom_ioctl_read_tocentry(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_tocentry entry;
	u8 requested_format;
	int ret;

	/* cdinfo(CD_DO_IOCTL, "entering CDROMREADTOCENTRY\n"); */

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&entry, argp, sizeof(entry)))
		return -EFAULT;

	requested_format = entry.cdte_format;
	if (requested_format != CDROM_MSF && requested_format != CDROM_LBA)
		return -EINVAL;
	/* make interface to low-level uniform */
	entry.cdte_format = CDROM_MSF;
	ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, &entry);
	if (ret)
		return ret;
	sanitize_format(&entry.cdte_addr, &entry.cdte_format, requested_format);

	if (copy_to_user(argp, &entry, sizeof(entry)))
		return -EFAULT;
	/* cdinfo(CD_DO_IOCTL, "CDROMREADTOCENTRY successful\n"); */
	return 0;
}

static int cdrom_ioctl_play_msf(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_msf msf;

	cdinfo(CD_DO_IOCTL, "entering CDROMPLAYMSF\n");

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&msf, argp, sizeof(msf)))
		return -EFAULT;
	return cdi->ops->audio_ioctl(cdi, CDROMPLAYMSF, &msf);
}

static int cdrom_ioctl_play_trkind(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_ti ti;
	int ret;

	cdinfo(CD_DO_IOCTL, "entering CDROMPLAYTRKIND\n");

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&ti, argp, sizeof(ti)))
		return -EFAULT;

	ret = check_for_audio_disc(cdi, cdi->ops);
	if (ret)
		return ret;
	return cdi->ops->audio_ioctl(cdi, CDROMPLAYTRKIND, &ti);
}
static int cdrom_ioctl_volctrl(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_volctrl volume;

	cdinfo(CD_DO_IOCTL, "entering CDROMVOLCTRL\n");

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	if (copy_from_user(&volume, argp, sizeof(volume)))
		return -EFAULT;
	return cdi->ops->audio_ioctl(cdi, CDROMVOLCTRL, &volume);
}

static int cdrom_ioctl_volread(struct cdrom_device_info *cdi,
		void __user *argp)
{
	struct cdrom_volctrl volume;
	int ret;

	cdinfo(CD_DO_IOCTL, "entering CDROMVOLREAD\n");

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;

	ret = cdi->ops->audio_ioctl(cdi, CDROMVOLREAD, &volume);
	if (ret)
		return ret;

	if (copy_to_user(argp, &volume, sizeof(volume)))
		return -EFAULT;
	return 0;
}

static int cdrom_ioctl_audioctl(struct cdrom_device_info *cdi,
		unsigned int cmd)
{
	int ret;

	cdinfo(CD_DO_IOCTL, "doing audio ioctl (start/stop/pause/resume)\n");

	if (!CDROM_CAN(CDC_PLAY_AUDIO))
		return -ENOSYS;
	ret = check_for_audio_disc(cdi, cdi->ops);
	if (ret)
		return ret;
	return cdi->ops->audio_ioctl(cdi, cmd, NULL);
}

/*
 * Just about every imaginable ioctl is supported in the Uniform layer
 * these days.
 * ATAPI / SCSI specific code now mainly resides in mmc_ioctl().
 */
int cdrom_ioctl(struct file * file, struct cdrom_device_info *cdi,
		struct inode *ip, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int ret;

	/*
	 * Try the generic SCSI command ioctl's first.
	 */
	ret = scsi_cmd_ioctl(file, ip->i_bdev->bd_disk, cmd, argp);
	if (ret != -ENOTTY)
		return ret;

	switch (cmd) {
	case CDROMMULTISESSION:
		return cdrom_ioctl_multisession(cdi, argp);
	case CDROMEJECT:
		return cdrom_ioctl_eject(cdi);
	case CDROMCLOSETRAY:
		return cdrom_ioctl_closetray(cdi);
	case CDROMEJECT_SW:
		return cdrom_ioctl_eject_sw(cdi, arg);
	case CDROM_MEDIA_CHANGED:
		return cdrom_ioctl_media_changed(cdi, arg);
	case CDROM_SET_OPTIONS:
		return cdrom_ioctl_set_options(cdi, arg);
	case CDROM_CLEAR_OPTIONS:
		return cdrom_ioctl_clear_options(cdi, arg);
	case CDROM_SELECT_SPEED:
		return cdrom_ioctl_select_speed(cdi, arg);
	case CDROM_SELECT_DISC:
		return cdrom_ioctl_select_disc(cdi, arg);
	case CDROMRESET:
		return cdrom_ioctl_reset(cdi, ip->i_bdev);
	case CDROM_LOCKDOOR:
		return cdrom_ioctl_lock_door(cdi, arg);
	case CDROM_DEBUG:
		return cdrom_ioctl_debug(cdi, arg);
	case CDROM_GET_CAPABILITY:
		return cdrom_ioctl_get_capability(cdi);
	case CDROM_GET_MCN:
		return cdrom_ioctl_get_mcn(cdi, argp);
	case CDROM_DRIVE_STATUS:
		return cdrom_ioctl_drive_status(cdi, arg);
	case CDROM_DISC_STATUS:
		return cdrom_ioctl_disc_status(cdi);
	case CDROM_CHANGER_NSLOTS:
		return cdrom_ioctl_changer_nslots(cdi);
	}

	/*
	 * Use the ioctls that are implemented through the generic_packet()
	 * interface. this may look at bit funny, but if -ENOTTY is
	 * returned that particular ioctl is not implemented and we
	 * let it go through the device specific ones.
	 */
	if (CDROM_CAN(CDC_GENERIC_PACKET)) {
		ret = mmc_ioctl(cdi, cmd, arg);
		if (ret != -ENOTTY)
			return ret;
	}

	/*
	 * Note: most of the cdinfo() calls are commented out here,
	 * because they fill up the sys log when CD players poll
	 * the drive.
	 */
	switch (cmd) {
	case CDROMSUBCHNL:
		return cdrom_ioctl_get_subchnl(cdi, argp);
	case CDROMREADTOCHDR:
		return cdrom_ioctl_read_tochdr(cdi, argp);
	case CDROMREADTOCENTRY:
		return cdrom_ioctl_read_tocentry(cdi, argp);
	case CDROMPLAYMSF:
		return cdrom_ioctl_play_msf(cdi, argp);
	case CDROMPLAYTRKIND:
		return cdrom_ioctl_play_trkind(cdi, argp);
	case CDROMVOLCTRL:
		return cdrom_ioctl_volctrl(cdi, argp);
	case CDROMVOLREAD:
		return cdrom_ioctl_volread(cdi, argp);
	case CDROMSTART:
	case CDROMSTOP:
	case CDROMPAUSE:
	case CDROMRESUME:
		return cdrom_ioctl_audioctl(cdi, cmd);
	}

	return -ENOSYS;
}

static inline
int msf_to_lba(char m, char s, char f)
{
	return (((m * CD_SECS) + s) * CD_FRAMES + f) - CD_MSF_OFFSET;
}

/*
 * Required when we need to use READ_10 to issue other than 2048 block
 * reads
 */
static int cdrom_switch_blocksize(struct cdrom_device_info *cdi, int size)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	struct packet_command cgc;
	struct modesel_head mh;

	memset(&mh, 0, sizeof(mh));
	mh.block_desc_length = 0x08;
	mh.block_length_med = (size >> 8) & 0xff;
	mh.block_length_lo = size & 0xff;

	memset(&cgc, 0, sizeof(cgc));
	cgc.cmd[0] = 0x15;
	cgc.cmd[1] = 1 << 4;
	cgc.cmd[4] = 12;
	cgc.buflen = sizeof(mh);
	cgc.buffer = (char *) &mh;
	cgc.data_direction = CGC_DATA_WRITE;
	mh.block_desc_length = 0x08;
	mh.block_length_med = (size >> 8) & 0xff;
	mh.block_length_lo = size & 0xff;

	return cdo->generic_packet(cdi, &cgc);
}

static int mmc_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
		     unsigned long arg)
{		
	struct cdrom_device_ops *cdo = cdi->ops;
	struct packet_command cgc;
	struct request_sense sense;
	unsigned char buffer[32];
	int ret = 0;

	memset(&cgc, 0, sizeof(cgc));

	/* build a unified command and queue it through
	   cdo->generic_packet() */
	switch (cmd) {
	case CDROMREADRAW:
	case CDROMREADMODE1:
	case CDROMREADMODE2: {
		struct cdrom_msf msf;
		int blocksize = 0, format = 0, lba;
		
		switch (cmd) {
		case CDROMREADRAW:
			blocksize = CD_FRAMESIZE_RAW;
			break;
		case CDROMREADMODE1:
			blocksize = CD_FRAMESIZE;
			format = 2;
			break;
		case CDROMREADMODE2:
			blocksize = CD_FRAMESIZE_RAW0;
			break;
		}
		IOCTL_IN(arg, struct cdrom_msf, msf);
		lba = msf_to_lba(msf.cdmsf_min0,msf.cdmsf_sec0,msf.cdmsf_frame0);
		/* FIXME: we need upper bound checking, too!! */
		if (lba < 0)
			return -EINVAL;
		cgc.buffer = (char *) kmalloc(blocksize, GFP_KERNEL);
		if (cgc.buffer == NULL)
			return -ENOMEM;
		memset(&sense, 0, sizeof(sense));
		cgc.sense = &sense;
		cgc.data_direction = CGC_DATA_READ;
		ret = cdrom_read_block(cdi, &cgc, lba, 1, format, blocksize);
		if (ret && sense.sense_key==0x05 && sense.asc==0x20 && sense.ascq==0x00) {
			/*
			 * SCSI-II devices are not required to support
			 * READ_CD, so let's try switching block size
			 */
			/* FIXME: switch back again... */
			if ((ret = cdrom_switch_blocksize(cdi, blocksize))) {
				kfree(cgc.buffer);
				return ret;
			}
			cgc.sense = NULL;
			ret = cdrom_read_cd(cdi, &cgc, lba, blocksize, 1);
			ret |= cdrom_switch_blocksize(cdi, blocksize);
		}
		if (!ret && copy_to_user((char __user *)arg, cgc.buffer, blocksize))
			ret = -EFAULT;
		kfree(cgc.buffer);
		return ret;
		}
	case CDROMREADAUDIO: {
		struct cdrom_read_audio ra;
		int lba;

		IOCTL_IN(arg, struct cdrom_read_audio, ra);

		if (ra.addr_format == CDROM_MSF)
			lba = msf_to_lba(ra.addr.msf.minute,
					 ra.addr.msf.second,
					 ra.addr.msf.frame);
		else if (ra.addr_format == CDROM_LBA)
			lba = ra.addr.lba;
		else
			return -EINVAL;

		/* FIXME: we need upper bound checking, too!! */
		if (lba < 0 || ra.nframes <= 0 || ra.nframes > CD_FRAMES)
			return -EINVAL;

		return cdrom_read_cdda(cdi, ra.buf, lba, ra.nframes);
		}
	case CDROMSUBCHNL: {
		struct cdrom_subchnl q;
		u_char requested, back;
		IOCTL_IN(arg, struct cdrom_subchnl, q);
		requested = q.cdsc_format;
		if (!((requested == CDROM_MSF) ||
		      (requested == CDROM_LBA)))
			return -EINVAL;
		q.cdsc_format = CDROM_MSF;
		if ((ret = cdrom_read_subchannel(cdi, &q, 0)))
			return ret;
		back = q.cdsc_format; /* local copy */
		sanitize_format(&q.cdsc_absaddr, &back, requested);
		sanitize_format(&q.cdsc_reladdr, &q.cdsc_format, requested);
		IOCTL_OUT(arg, struct cdrom_subchnl, q);
		/* cdinfo(CD_DO_IOCTL, "CDROMSUBCHNL successful\n"); */ 
		return 0;
		}
	case CDROMPLAYMSF: {
		struct cdrom_msf msf;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYMSF\n");
		IOCTL_IN(arg, struct cdrom_msf, msf);
		cgc.cmd[0] = GPCMD_PLAY_AUDIO_MSF;
		cgc.cmd[3] = msf.cdmsf_min0;
		cgc.cmd[4] = msf.cdmsf_sec0;
		cgc.cmd[5] = msf.cdmsf_frame0;
		cgc.cmd[6] = msf.cdmsf_min1;
		cgc.cmd[7] = msf.cdmsf_sec1;
		cgc.cmd[8] = msf.cdmsf_frame1;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}
	case CDROMPLAYBLK: {
		struct cdrom_blk blk;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYBLK\n");
		IOCTL_IN(arg, struct cdrom_blk, blk);
		cgc.cmd[0] = GPCMD_PLAY_AUDIO_10;
		cgc.cmd[2] = (blk.from >> 24) & 0xff;
		cgc.cmd[3] = (blk.from >> 16) & 0xff;
		cgc.cmd[4] = (blk.from >>  8) & 0xff;
		cgc.cmd[5] = blk.from & 0xff;
		cgc.cmd[7] = (blk.len >> 8) & 0xff;
		cgc.cmd[8] = blk.len & 0xff;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}
	case CDROMVOLCTRL:
	case CDROMVOLREAD: {
		struct cdrom_volctrl volctrl;
		char mask[sizeof(buffer)];
		unsigned short offset;

		cdinfo(CD_DO_IOCTL, "entering CDROMVOLUME\n");

		IOCTL_IN(arg, struct cdrom_volctrl, volctrl);

		cgc.buffer = buffer;
		cgc.buflen = 24;
		if ((ret = cdrom_mode_sense(cdi, &cgc, GPMODE_AUDIO_CTL_PAGE, 0)))
		    return ret;
		
		/* originally the code depended on buffer[1] to determine
		   how much data is available for transfer. buffer[1] is
		   unfortunately ambigious and the only reliable way seem
		   to be to simply skip over the block descriptor... */
		offset = 8 + be16_to_cpu(*(unsigned short *)(buffer+6));

		if (offset + 16 > sizeof(buffer))
			return -E2BIG;

		if (offset + 16 > cgc.buflen) {
			cgc.buflen = offset+16;
			ret = cdrom_mode_sense(cdi, &cgc,
						GPMODE_AUDIO_CTL_PAGE, 0);
			if (ret)
				return ret;
		}

		/* sanity check */
		if ((buffer[offset] & 0x3f) != GPMODE_AUDIO_CTL_PAGE ||
				buffer[offset+1] < 14)
			return -EINVAL;

		/* now we have the current volume settings. if it was only
		   a CDROMVOLREAD, return these values */
		if (cmd == CDROMVOLREAD) {
			volctrl.channel0 = buffer[offset+9];
			volctrl.channel1 = buffer[offset+11];
			volctrl.channel2 = buffer[offset+13];
			volctrl.channel3 = buffer[offset+15];
			IOCTL_OUT(arg, struct cdrom_volctrl, volctrl);
			return 0;
		}
		
		/* get the volume mask */
		cgc.buffer = mask;
		if ((ret = cdrom_mode_sense(cdi, &cgc, 
				GPMODE_AUDIO_CTL_PAGE, 1)))
			return ret;

		buffer[offset+9] = volctrl.channel0 & mask[offset+9];
		buffer[offset+11] = volctrl.channel1 & mask[offset+11];
		buffer[offset+13] = volctrl.channel2 & mask[offset+13];
		buffer[offset+15] = volctrl.channel3 & mask[offset+15];

		/* set volume */
		cgc.buffer = buffer + offset - 8;
		memset(cgc.buffer, 0, 8);
		return cdrom_mode_select(cdi, &cgc);
		}

	case CDROMSTART:
	case CDROMSTOP: {
		cdinfo(CD_DO_IOCTL, "entering CDROMSTART/CDROMSTOP\n"); 
		cgc.cmd[0] = GPCMD_START_STOP_UNIT;
		cgc.cmd[1] = 1;
		cgc.cmd[4] = (cmd == CDROMSTART) ? 1 : 0;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}

	case CDROMPAUSE:
	case CDROMRESUME: {
		cdinfo(CD_DO_IOCTL, "entering CDROMPAUSE/CDROMRESUME\n"); 
		cgc.cmd[0] = GPCMD_PAUSE_RESUME;
		cgc.cmd[8] = (cmd == CDROMRESUME) ? 1 : 0;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}

	case DVD_READ_STRUCT: {
		dvd_struct *s;
		int size = sizeof(dvd_struct);
		if (!CDROM_CAN(CDC_DVD))
			return -ENOSYS;
		if ((s = (dvd_struct *) kmalloc(size, GFP_KERNEL)) == NULL)
			return -ENOMEM;
		cdinfo(CD_DO_IOCTL, "entering DVD_READ_STRUCT\n"); 
		if (copy_from_user(s, (dvd_struct __user *)arg, size)) {
			kfree(s);
			return -EFAULT;
		}
		if ((ret = dvd_read_struct(cdi, s))) {
			kfree(s);
			return ret;
		}
		if (copy_to_user((dvd_struct __user *)arg, s, size))
			ret = -EFAULT;
		kfree(s);
		return ret;
		}

	case DVD_AUTH: {
		dvd_authinfo ai;
		if (!CDROM_CAN(CDC_DVD))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "entering DVD_AUTH\n"); 
		IOCTL_IN(arg, dvd_authinfo, ai);
		if ((ret = dvd_do_auth (cdi, &ai)))
			return ret;
		IOCTL_OUT(arg, dvd_authinfo, ai);
		return 0;
		}

	case CDROM_NEXT_WRITABLE: {
		long next = 0;
		cdinfo(CD_DO_IOCTL, "entering CDROM_NEXT_WRITABLE\n"); 
		if ((ret = cdrom_get_next_writable(cdi, &next)))
			return ret;
		IOCTL_OUT(arg, long, next);
		return 0;
		}
	case CDROM_LAST_WRITTEN: {
		long last = 0;
		cdinfo(CD_DO_IOCTL, "entering CDROM_LAST_WRITTEN\n"); 
		if ((ret = cdrom_get_last_written(cdi, &last)))
			return ret;
		IOCTL_OUT(arg, long, last);
		return 0;
		}
	} /* switch */

	return -ENOTTY;
}

static int cdrom_get_track_info(struct cdrom_device_info *cdi, __u16 track, __u8 type,
			 track_information *ti)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	struct packet_command cgc;
	int ret, buflen;

	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
	cgc.cmd[1] = type & 3;
	cgc.cmd[4] = (track & 0xff00) >> 8;
	cgc.cmd[5] = track & 0xff;
	cgc.cmd[8] = 8;
	cgc.quiet = 1;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;
	
	buflen = be16_to_cpu(ti->track_information_length) +
		     sizeof(ti->track_information_length);

	if (buflen > sizeof(track_information))
		buflen = sizeof(track_information);

	cgc.cmd[8] = cgc.buflen = buflen;
	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	/* return actual fill size */
	return buflen;
}

/* requires CD R/RW */
static int cdrom_get_disc_info(struct cdrom_device_info *cdi, disc_information *di)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	struct packet_command cgc;
	int ret, buflen;

	/* set up command and get the disc info */
	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
	cgc.cmd[8] = cgc.buflen = 2;
	cgc.quiet = 1;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	/* not all drives have the same disc_info length, so requeue
	 * packet with the length the drive tells us it can supply
	 */
	buflen = be16_to_cpu(di->disc_information_length) +
		     sizeof(di->disc_information_length);

	if (buflen > sizeof(disc_information))
		buflen = sizeof(disc_information);

	cgc.cmd[8] = cgc.buflen = buflen;
	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	/* return actual fill size */
	return buflen;
}

/* return the last written block on the CD-R media. this is for the udf
   file system. */
int cdrom_get_last_written(struct cdrom_device_info *cdi, long *last_written)
{
	struct cdrom_tocentry toc;
	disc_information di;
	track_information ti;
	__u32 last_track;
	int ret = -1, ti_size;

	if (!CDROM_CAN(CDC_GENERIC_PACKET))
		goto use_toc;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < (int)(offsetof(typeof(di), last_track_lsb)
			+ sizeof(di.last_track_lsb)))
		goto use_toc;

	/* if unit didn't return msb, it's zeroed by cdrom_get_disc_info */
	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
	ti_size = cdrom_get_track_info(cdi, last_track, 1, &ti);
	if (ti_size < (int)offsetof(typeof(ti), track_start))
		goto use_toc;

	/* if this track is blank, try the previous. */
	if (ti.blank) {
		if (last_track==1)
			goto use_toc;
		last_track--;
		ti_size = cdrom_get_track_info(cdi, last_track, 1, &ti);
	}

	if (ti_size < (int)(offsetof(typeof(ti), track_size)
				+ sizeof(ti.track_size)))
		goto use_toc;

	/* if last recorded field is valid, return it. */
	if (ti.lra_v && ti_size >= (int)(offsetof(typeof(ti), last_rec_address)
				+ sizeof(ti.last_rec_address))) {
		*last_written = be32_to_cpu(ti.last_rec_address);
	} else {
		/* make it up instead */
		*last_written = be32_to_cpu(ti.track_start) +
				be32_to_cpu(ti.track_size);
		if (ti.free_blocks)
			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
	}
	return 0;

	/* this is where we end up if the drive either can't do a
	   GPCMD_READ_DISC_INFO or GPCMD_READ_TRACK_RZONE_INFO or if
	   it doesn't give enough information or fails. then we return
	   the toc contents. */
use_toc:
	toc.cdte_format = CDROM_MSF;
	toc.cdte_track = CDROM_LEADOUT;
	if ((ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, &toc)))
		return ret;
	sanitize_format(&toc.cdte_addr, &toc.cdte_format, CDROM_LBA);
	*last_written = toc.cdte_addr.lba;
	return 0;
}

/* return the next writable block. also for udf file system. */
static int cdrom_get_next_writable(struct cdrom_device_info *cdi, long *next_writable)
{
	disc_information di;
	track_information ti;
	__u16 last_track;
	int ret, ti_size;

	if (!CDROM_CAN(CDC_GENERIC_PACKET))
		goto use_last_written;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < offsetof(typeof(di), last_track_lsb)
				+ sizeof(di.last_track_lsb))
		goto use_last_written;

	/* if unit didn't return msb, it's zeroed by cdrom_get_disc_info */
	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
	ti_size = cdrom_get_track_info(cdi, last_track, 1, &ti);
	if (ti_size < 0 || ti_size < offsetof(typeof(ti), track_start))
		goto use_last_written;

        /* if this track is blank, try the previous. */
	if (ti.blank) {
		if (last_track == 1)
			goto use_last_written;
		last_track--;
		ti_size = cdrom_get_track_info(cdi, last_track, 1, &ti);
		if (ti_size < 0)
			goto use_last_written;
	}

	/* if next recordable address field is valid, use it. */
	if (ti.nwa_v && ti_size >= offsetof(typeof(ti), next_writable)
				+ sizeof(ti.next_writable)) {
		*next_writable = be32_to_cpu(ti.next_writable);
		return 0;
	}

use_last_written:
	if ((ret = cdrom_get_last_written(cdi, next_writable))) {
		*next_writable = 0;
		return ret;
	} else {
		*next_writable += 7;
		return 0;
	}
}

EXPORT_SYMBOL(cdrom_get_last_written);
EXPORT_SYMBOL(register_cdrom);
EXPORT_SYMBOL(unregister_cdrom);
EXPORT_SYMBOL(cdrom_open);
EXPORT_SYMBOL(cdrom_release);
EXPORT_SYMBOL(cdrom_ioctl);
EXPORT_SYMBOL(cdrom_media_changed);
EXPORT_SYMBOL(cdrom_number_of_slots);
EXPORT_SYMBOL(cdrom_mode_select);
EXPORT_SYMBOL(cdrom_mode_sense);
EXPORT_SYMBOL(init_cdrom_command);
EXPORT_SYMBOL(cdrom_get_media_event);

#ifdef CONFIG_SYSCTL

#define CDROM_STR_SIZE 1000

static struct cdrom_sysctl_settings {
	char	info[CDROM_STR_SIZE];	/* general info */
	int	autoclose;		/* close tray upon mount, etc */
	int	autoeject;		/* eject on umount */
	int	debug;			/* turn on debugging messages */
	int	lock;			/* lock the door on device open */
	int	check;			/* check media type */
} cdrom_sysctl_settings;

static int cdrom_sysctl_info(ctl_table *ctl, int write, struct file * filp,
                           void __user *buffer, size_t *lenp, loff_t *ppos)
{
        int pos;
	struct cdrom_device_info *cdi;
	char *info = cdrom_sysctl_settings.info;
	
	if (!*lenp || (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}

	pos = sprintf(info, "CD-ROM information, " VERSION "\n");
	
	pos += sprintf(info+pos, "\ndrive name:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%s", cdi->name);

	pos += sprintf(info+pos, "\ndrive speed:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", cdi->speed);

	pos += sprintf(info+pos, "\ndrive # of slots:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", cdi->capacity);

	pos += sprintf(info+pos, "\nCan close tray:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_CLOSE_TRAY) != 0);

	pos += sprintf(info+pos, "\nCan open tray:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_OPEN_TRAY) != 0);

	pos += sprintf(info+pos, "\nCan lock tray:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_LOCK) != 0);

	pos += sprintf(info+pos, "\nCan change speed:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_SELECT_SPEED) != 0);

	pos += sprintf(info+pos, "\nCan select disk:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_SELECT_DISC) != 0);

	pos += sprintf(info+pos, "\nCan read multisession:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MULTI_SESSION) != 0);

	pos += sprintf(info+pos, "\nCan read MCN:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MCN) != 0);

	pos += sprintf(info+pos, "\nReports media changed:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MEDIA_CHANGED) != 0);

	pos += sprintf(info+pos, "\nCan play audio:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_PLAY_AUDIO) != 0);

	pos += sprintf(info+pos, "\nCan write CD-R:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_CD_R) != 0);

	pos += sprintf(info+pos, "\nCan write CD-RW:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_CD_RW) != 0);

	pos += sprintf(info+pos, "\nCan read DVD:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_DVD) != 0);

	pos += sprintf(info+pos, "\nCan write DVD-R:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_DVD_R) != 0);

	pos += sprintf(info+pos, "\nCan write DVD-RAM:");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_DVD_RAM) != 0);

	pos += sprintf(info+pos, "\nCan read MRW:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MRW) != 0);

	pos += sprintf(info+pos, "\nCan write MRW:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MRW_W) != 0);

	pos += sprintf(info+pos, "\nCan write RAM:\t");
	for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next)
	    pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_RAM) != 0);

	strcpy(info+pos,"\n\n");
		
        return proc_dostring(ctl, write, filp, buffer, lenp, ppos);
}

/* Unfortunately, per device settings are not implemented through
   procfs/sysctl yet. When they are, this will naturally disappear. For now
   just update all drives. Later this will become the template on which
   new registered drives will be based. */
static void cdrom_update_settings(void)
{
	struct cdrom_device_info *cdi;

	for (cdi = topCdromPtr; cdi != NULL; cdi = cdi->next) {
		if (autoclose && CDROM_CAN(CDC_CLOSE_TRAY))
			cdi->options |= CDO_AUTO_CLOSE;
		else if (!autoclose)
			cdi->options &= ~CDO_AUTO_CLOSE;
		if (autoeject && CDROM_CAN(CDC_OPEN_TRAY))
			cdi->options |= CDO_AUTO_EJECT;
		else if (!autoeject)
			cdi->options &= ~CDO_AUTO_EJECT;
		if (lockdoor && CDROM_CAN(CDC_LOCK))
			cdi->options |= CDO_LOCK;
		else if (!lockdoor)
			cdi->options &= ~CDO_LOCK;
		if (check_media_type)
			cdi->options |= CDO_CHECK_TYPE;
		else
			cdi->options &= ~CDO_CHECK_TYPE;
	}
}

static int cdrom_sysctl_handler(ctl_table *ctl, int write, struct file * filp,
				void __user *buffer, size_t *lenp, loff_t *ppos)
{
	int *valp = ctl->data;
	int val = *valp;
	int ret;
	
	ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);

	if (write && *valp != val) {
	
		/* we only care for 1 or 0. */
		if (*valp)
			*valp = 1;
		else
			*valp = 0;

		switch (ctl->ctl_name) {
		case DEV_CDROM_AUTOCLOSE: {
			if (valp == &cdrom_sysctl_settings.autoclose)
				autoclose = cdrom_sysctl_settings.autoclose;
			break;
			}
		case DEV_CDROM_AUTOEJECT: {
			if (valp == &cdrom_sysctl_settings.autoeject)
				autoeject = cdrom_sysctl_settings.autoeject;
			break;
			}
		case DEV_CDROM_DEBUG: {
			if (valp == &cdrom_sysctl_settings.debug)
				debug = cdrom_sysctl_settings.debug;
			break;
			}
		case DEV_CDROM_LOCK: {
			if (valp == &cdrom_sysctl_settings.lock)
				lockdoor = cdrom_sysctl_settings.lock;
			break;
			}
		case DEV_CDROM_CHECK_MEDIA: {
			if (valp == &cdrom_sysctl_settings.check)
				check_media_type = cdrom_sysctl_settings.check;
			break;
			}
		}
		/* update the option flags according to the changes. we
		   don't have per device options through sysctl yet,
		   but we will have and then this will disappear. */
		cdrom_update_settings();
	}

        return ret;
}

/* Place files in /proc/sys/dev/cdrom */
static ctl_table cdrom_table[] = {
	{
		.ctl_name	= DEV_CDROM_INFO,
		.procname	= "info",
		.data		= &cdrom_sysctl_settings.info, 
		.maxlen		= CDROM_STR_SIZE,
		.mode		= 0444,
		.proc_handler	= &cdrom_sysctl_info,
	},
	{
		.ctl_name	= DEV_CDROM_AUTOCLOSE,
		.procname	= "autoclose",
		.data		= &cdrom_sysctl_settings.autoclose,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &cdrom_sysctl_handler,
	},
	{
		.ctl_name	= DEV_CDROM_AUTOEJECT,
		.procname	= "autoeject",
		.data		= &cdrom_sysctl_settings.autoeject,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &cdrom_sysctl_handler,
	},
	{
		.ctl_name	= DEV_CDROM_DEBUG,
		.procname	= "debug",
		.data		= &cdrom_sysctl_settings.debug,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &cdrom_sysctl_handler,
	},
	{
		.ctl_name	= DEV_CDROM_LOCK,
		.procname	= "lock",
		.data		= &cdrom_sysctl_settings.lock,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &cdrom_sysctl_handler,
	},
	{
		.ctl_name	= DEV_CDROM_CHECK_MEDIA,
		.procname	= "check_media",
		.data		= &cdrom_sysctl_settings.check,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &cdrom_sysctl_handler
	},
	{ .ctl_name = 0 }
};

static ctl_table cdrom_cdrom_table[] = {
	{
		.ctl_name	= DEV_CDROM,
		.procname	= "cdrom",
		.maxlen		= 0,
		.mode		= 0555,
		.child		= cdrom_table,
	},
	{ .ctl_name = 0 }
};

/* Make sure that /proc/sys/dev is there */
static ctl_table cdrom_root_table[] = {
	{
		.ctl_name	= CTL_DEV,
		.procname	= "dev",
		.maxlen		= 0,
		.mode		= 0555,
		.child		= cdrom_cdrom_table,
	},
	{ .ctl_name = 0 }
};
static struct ctl_table_header *cdrom_sysctl_header;

static void cdrom_sysctl_register(void)
{
	static int initialized;

	if (initialized == 1)
		return;

	cdrom_sysctl_header = register_sysctl_table(cdrom_root_table, 1);
	if (cdrom_root_table->ctl_name && cdrom_root_table->child->de)
		cdrom_root_table->child->de->owner = THIS_MODULE;

	/* set the defaults */
	cdrom_sysctl_settings.autoclose = autoclose;
	cdrom_sysctl_settings.autoeject = autoeject;
	cdrom_sysctl_settings.debug = debug;
	cdrom_sysctl_settings.lock = lockdoor;
	cdrom_sysctl_settings.check = check_media_type;

	initialized = 1;
}

static void cdrom_sysctl_unregister(void)
{
	if (cdrom_sysctl_header)
		unregister_sysctl_table(cdrom_sysctl_header);
}

#endif /* CONFIG_SYSCTL */

static int __init cdrom_init(void)
{
#ifdef CONFIG_SYSCTL
	cdrom_sysctl_register();
#endif
	return 0;
}

static void __exit cdrom_exit(void)
{
	printk(KERN_INFO "Uniform CD-ROM driver unloaded\n");
#ifdef CONFIG_SYSCTL
	cdrom_sysctl_unregister();
#endif
}

module_init(cdrom_init);
module_exit(cdrom_exit);
MODULE_LICENSE("GPL");