aboutsummaryrefslogtreecommitdiff
path: root/hw/ide/atapi.c
blob: fe2fb0b8067d157a00938e8c6a3fcb010d30df67 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
/*
 * QEMU ATAPI Emulation
 *
 * Copyright (c) 2003 Fabrice Bellard
 * Copyright (c) 2006 Openedhand Ltd.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "hw/ide/internal.h"
#include "hw/scsi.h"

static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret);

static void padstr8(uint8_t *buf, int buf_size, const char *src)
{
    int i;
    for(i = 0; i < buf_size; i++) {
        if (*src)
            buf[i] = *src++;
        else
            buf[i] = ' ';
    }
}

static inline void cpu_to_ube16(uint8_t *buf, int val)
{
    buf[0] = val >> 8;
    buf[1] = val & 0xff;
}

static inline void cpu_to_ube32(uint8_t *buf, unsigned int val)
{
    buf[0] = val >> 24;
    buf[1] = val >> 16;
    buf[2] = val >> 8;
    buf[3] = val & 0xff;
}

static inline int ube16_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 8) | buf[1];
}

static inline int ube32_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
}

static void lba_to_msf(uint8_t *buf, int lba)
{
    lba += 150;
    buf[0] = (lba / 75) / 60;
    buf[1] = (lba / 75) % 60;
    buf[2] = lba % 75;
}

static inline int media_present(IDEState *s)
{
    return (s->nb_sectors > 0);
}

/* XXX: DVDs that could fit on a CD will be reported as a CD */
static inline int media_is_dvd(IDEState *s)
{
    return (media_present(s) && s->nb_sectors > CD_MAX_SECTORS);
}

static inline int media_is_cd(IDEState *s)
{
    return (media_present(s) && s->nb_sectors <= CD_MAX_SECTORS);
}

static void cd_data_to_raw(uint8_t *buf, int lba)
{
    /* sync bytes */
    buf[0] = 0x00;
    memset(buf + 1, 0xff, 10);
    buf[11] = 0x00;
    buf += 12;
    /* MSF */
    lba_to_msf(buf, lba);
    buf[3] = 0x01; /* mode 1 data */
    buf += 4;
    /* data */
    buf += 2048;
    /* XXX: ECC not computed */
    memset(buf, 0, 288);
}

static int cd_read_sector(BlockDriverState *bs, int lba, uint8_t *buf,
                           int sector_size)
{
    int ret;

    switch(sector_size) {
    case 2048:
        ret = bdrv_read(bs, (int64_t)lba << 2, buf, 4);
        break;
    case 2352:
        ret = bdrv_read(bs, (int64_t)lba << 2, buf + 16, 4);
        if (ret < 0)
            return ret;
        cd_data_to_raw(buf, lba);
        break;
    default:
        ret = -EIO;
        break;
    }
    return ret;
}

void ide_atapi_cmd_ok(IDEState *s)
{
    s->error = 0;
    s->status = READY_STAT | SEEK_STAT;
    s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
    ide_set_irq(s->bus);
}

void ide_atapi_cmd_error(IDEState *s, int sense_key, int asc)
{
#ifdef DEBUG_IDE_ATAPI
    printf("atapi_cmd_error: sense=0x%x asc=0x%x\n", sense_key, asc);
#endif
    s->error = sense_key << 4;
    s->status = READY_STAT | ERR_STAT;
    s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
    s->sense_key = sense_key;
    s->asc = asc;
    ide_set_irq(s->bus);
}

void ide_atapi_io_error(IDEState *s, int ret)
{
    /* XXX: handle more errors */
    if (ret == -ENOMEDIUM) {
        ide_atapi_cmd_error(s, SENSE_NOT_READY,
                            ASC_MEDIUM_NOT_PRESENT);
    } else {
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_LOGICAL_BLOCK_OOR);
    }
}

/* The whole ATAPI transfer logic is handled in this function */
void ide_atapi_cmd_reply_end(IDEState *s)
{
    int byte_count_limit, size, ret;
#ifdef DEBUG_IDE_ATAPI
    printf("reply: tx_size=%d elem_tx_size=%d index=%d\n",
           s->packet_transfer_size,
           s->elementary_transfer_size,
           s->io_buffer_index);
#endif
    if (s->packet_transfer_size <= 0) {
        /* end of transfer */
        ide_transfer_stop(s);
        s->status = READY_STAT | SEEK_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s->bus);
#ifdef DEBUG_IDE_ATAPI
        printf("status=0x%x\n", s->status);
#endif
    } else {
        /* see if a new sector must be read */
        if (s->lba != -1 && s->io_buffer_index >= s->cd_sector_size) {
            ret = cd_read_sector(s->bs, s->lba, s->io_buffer, s->cd_sector_size);
            if (ret < 0) {
                ide_transfer_stop(s);
                ide_atapi_io_error(s, ret);
                return;
            }
            s->lba++;
            s->io_buffer_index = 0;
        }
        if (s->elementary_transfer_size > 0) {
            /* there are some data left to transmit in this elementary
               transfer */
            size = s->cd_sector_size - s->io_buffer_index;
            if (size > s->elementary_transfer_size)
                size = s->elementary_transfer_size;
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
                               size, ide_atapi_cmd_reply_end);
        } else {
            /* a new transfer is needed */
            s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
            byte_count_limit = s->lcyl | (s->hcyl << 8);
#ifdef DEBUG_IDE_ATAPI
            printf("byte_count_limit=%d\n", byte_count_limit);
#endif
            if (byte_count_limit == 0xffff)
                byte_count_limit--;
            size = s->packet_transfer_size;
            if (size > byte_count_limit) {
                /* byte count limit must be even if this case */
                if (byte_count_limit & 1)
                    byte_count_limit--;
                size = byte_count_limit;
            }
            s->lcyl = size;
            s->hcyl = size >> 8;
            s->elementary_transfer_size = size;
            /* we cannot transmit more than one sector at a time */
            if (s->lba != -1) {
                if (size > (s->cd_sector_size - s->io_buffer_index))
                    size = (s->cd_sector_size - s->io_buffer_index);
            }
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
                               size, ide_atapi_cmd_reply_end);
            ide_set_irq(s->bus);
#ifdef DEBUG_IDE_ATAPI
            printf("status=0x%x\n", s->status);
#endif
        }
    }
}

/* send a reply of 'size' bytes in s->io_buffer to an ATAPI command */
static void ide_atapi_cmd_reply(IDEState *s, int size, int max_size)
{
    if (size > max_size)
        size = max_size;
    s->lba = -1; /* no sector read */
    s->packet_transfer_size = size;
    s->io_buffer_size = size;    /* dma: send the reply data as one chunk */
    s->elementary_transfer_size = 0;
    s->io_buffer_index = 0;

    if (s->atapi_dma) {
        s->status = READY_STAT | SEEK_STAT | DRQ_STAT;
        s->bus->dma->ops->start_dma(s->bus->dma, s,
                                   ide_atapi_cmd_read_dma_cb);
    } else {
        s->status = READY_STAT | SEEK_STAT;
        ide_atapi_cmd_reply_end(s);
    }
}

/* start a CD-CDROM read command */
static void ide_atapi_cmd_read_pio(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->elementary_transfer_size = 0;
    s->io_buffer_index = sector_size;
    s->cd_sector_size = sector_size;

    s->status = READY_STAT | SEEK_STAT;
    ide_atapi_cmd_reply_end(s);
}

static void ide_atapi_cmd_check_status(IDEState *s)
{
#ifdef DEBUG_IDE_ATAPI
    printf("atapi_cmd_check_status\n");
#endif
    s->error = MC_ERR | (SENSE_UNIT_ATTENTION << 4);
    s->status = ERR_STAT;
    s->nsector = 0;
    ide_set_irq(s->bus);
}
/* ATAPI DMA support */

/* XXX: handle read errors */
static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret)
{
    IDEState *s = opaque;
    int data_offset, n;

    if (ret < 0) {
        ide_atapi_io_error(s, ret);
        goto eot;
    }

    if (s->io_buffer_size > 0) {
        /*
         * For a cdrom read sector command (s->lba != -1),
         * adjust the lba for the next s->io_buffer_size chunk
         * and dma the current chunk.
         * For a command != read (s->lba == -1), just transfer
         * the reply data.
         */
        if (s->lba != -1) {
            if (s->cd_sector_size == 2352) {
                n = 1;
                cd_data_to_raw(s->io_buffer, s->lba);
            } else {
                n = s->io_buffer_size >> 11;
            }
            s->lba += n;
        }
        s->packet_transfer_size -= s->io_buffer_size;
        if (s->bus->dma->ops->rw_buf(s->bus->dma, 1) == 0)
            goto eot;
    }

    if (s->packet_transfer_size <= 0) {
        s->status = READY_STAT | SEEK_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s->bus);
    eot:
        s->bus->dma->ops->add_status(s->bus->dma, BM_STATUS_INT);
        ide_set_inactive(s);
        return;
    }

    s->io_buffer_index = 0;
    if (s->cd_sector_size == 2352) {
        n = 1;
        s->io_buffer_size = s->cd_sector_size;
        data_offset = 16;
    } else {
        n = s->packet_transfer_size >> 11;
        if (n > (IDE_DMA_BUF_SECTORS / 4))
            n = (IDE_DMA_BUF_SECTORS / 4);
        s->io_buffer_size = n * 2048;
        data_offset = 0;
    }
#ifdef DEBUG_AIO
    printf("aio_read_cd: lba=%u n=%d\n", s->lba, n);
#endif
    s->bus->dma->iov.iov_base = (void *)(s->io_buffer + data_offset);
    s->bus->dma->iov.iov_len = n * 4 * 512;
    qemu_iovec_init_external(&s->bus->dma->qiov, &s->bus->dma->iov, 1);
    s->bus->dma->aiocb = bdrv_aio_readv(s->bs, (int64_t)s->lba << 2,
                                       &s->bus->dma->qiov, n * 4,
                                       ide_atapi_cmd_read_dma_cb, s);
    if (!s->bus->dma->aiocb) {
        /* Note: media not present is the most likely case */
        ide_atapi_cmd_error(s, SENSE_NOT_READY,
                            ASC_MEDIUM_NOT_PRESENT);
        goto eot;
    }
}

/* start a CD-CDROM read command with DMA */
/* XXX: test if DMA is available */
static void ide_atapi_cmd_read_dma(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->io_buffer_index = 0;
    s->io_buffer_size = 0;
    s->cd_sector_size = sector_size;

    /* XXX: check if BUSY_STAT should be set */
    s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
    s->bus->dma->ops->start_dma(s->bus->dma, s,
                               ide_atapi_cmd_read_dma_cb);
}

static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors,
                               int sector_size)
{
#ifdef DEBUG_IDE_ATAPI
    printf("read %s: LBA=%d nb_sectors=%d\n", s->atapi_dma ? "dma" : "pio",
        lba, nb_sectors);
#endif
    if (s->atapi_dma) {
        ide_atapi_cmd_read_dma(s, lba, nb_sectors, sector_size);
    } else {
        ide_atapi_cmd_read_pio(s, lba, nb_sectors, sector_size);
    }
}

static inline uint8_t ide_atapi_set_profile(uint8_t *buf, uint8_t *index,
                                            uint16_t profile)
{
    uint8_t *buf_profile = buf + 12; /* start of profiles */

    buf_profile += ((*index) * 4); /* start of indexed profile */
    cpu_to_ube16 (buf_profile, profile);
    buf_profile[2] = ((buf_profile[0] == buf[6]) && (buf_profile[1] == buf[7]));

    /* each profile adds 4 bytes to the response */
    (*index)++;
    buf[11] += 4; /* Additional Length */

    return 4;
}

static int ide_dvd_read_structure(IDEState *s, int format,
                                  const uint8_t *packet, uint8_t *buf)
{
    switch (format) {
        case 0x0: /* Physical format information */
            {
                int layer = packet[6];
                uint64_t total_sectors;

                if (layer != 0)
                    return -ASC_INV_FIELD_IN_CMD_PACKET;

                total_sectors = s->nb_sectors >> 2;
                if (total_sectors == 0) {
                    return -ASC_MEDIUM_NOT_PRESENT;
                }

                buf[4] = 1;   /* DVD-ROM, part version 1 */
                buf[5] = 0xf; /* 120mm disc, minimum rate unspecified */
                buf[6] = 1;   /* one layer, read-only (per MMC-2 spec) */
                buf[7] = 0;   /* default densities */

                /* FIXME: 0x30000 per spec? */
                cpu_to_ube32(buf + 8, 0); /* start sector */
                cpu_to_ube32(buf + 12, total_sectors - 1); /* end sector */
                cpu_to_ube32(buf + 16, total_sectors - 1); /* l0 end sector */

                /* Size of buffer, not including 2 byte size field */
                cpu_to_be16wu((uint16_t *)buf, 2048 + 2);

                /* 2k data + 4 byte header */
                return (2048 + 4);
            }

        case 0x01: /* DVD copyright information */
            buf[4] = 0; /* no copyright data */
            buf[5] = 0; /* no region restrictions */

            /* Size of buffer, not including 2 byte size field */
            cpu_to_be16wu((uint16_t *)buf, 4 + 2);

            /* 4 byte header + 4 byte data */
            return (4 + 4);

        case 0x03: /* BCA information - invalid field for no BCA info */
            return -ASC_INV_FIELD_IN_CMD_PACKET;

        case 0x04: /* DVD disc manufacturing information */
            /* Size of buffer, not including 2 byte size field */
            cpu_to_be16wu((uint16_t *)buf, 2048 + 2);

            /* 2k data + 4 byte header */
            return (2048 + 4);

        case 0xff:
            /*
             * This lists all the command capabilities above.  Add new ones
             * in order and update the length and buffer return values.
             */

            buf[4] = 0x00; /* Physical format */
            buf[5] = 0x40; /* Not writable, is readable */
            cpu_to_be16wu((uint16_t *)(buf + 6), 2048 + 4);

            buf[8] = 0x01; /* Copyright info */
            buf[9] = 0x40; /* Not writable, is readable */
            cpu_to_be16wu((uint16_t *)(buf + 10), 4 + 4);

            buf[12] = 0x03; /* BCA info */
            buf[13] = 0x40; /* Not writable, is readable */
            cpu_to_be16wu((uint16_t *)(buf + 14), 188 + 4);

            buf[16] = 0x04; /* Manufacturing info */
            buf[17] = 0x40; /* Not writable, is readable */
            cpu_to_be16wu((uint16_t *)(buf + 18), 2048 + 4);

            /* Size of buffer, not including 2 byte size field */
            cpu_to_be16wu((uint16_t *)buf, 16 + 2);

            /* data written + 4 byte header */
            return (16 + 4);

        default: /* TODO: formats beyond DVD-ROM requires */
            return -ASC_INV_FIELD_IN_CMD_PACKET;
    }
}

static unsigned int event_status_media(IDEState *s,
                                       uint8_t *buf)
{
    enum media_event_code {
        MEC_NO_CHANGE = 0,       /* Status unchanged */
        MEC_EJECT_REQUESTED,     /* received a request from user to eject */
        MEC_NEW_MEDIA,           /* new media inserted and ready for access */
        MEC_MEDIA_REMOVAL,       /* only for media changers */
        MEC_MEDIA_CHANGED,       /* only for media changers */
        MEC_BG_FORMAT_COMPLETED, /* MRW or DVD+RW b/g format completed */
        MEC_BG_FORMAT_RESTARTED, /* MRW or DVD+RW b/g format restarted */
    };
    enum media_status {
        MS_TRAY_OPEN = 1,
        MS_MEDIA_PRESENT = 2,
    };
    uint8_t event_code, media_status;

    media_status = 0;
    if (s->bs->tray_open) {
        media_status = MS_TRAY_OPEN;
    } else if (bdrv_is_inserted(s->bs)) {
        media_status = MS_MEDIA_PRESENT;
    }

    /* Event notification descriptor */
    event_code = MEC_NO_CHANGE;
    if (media_status != MS_TRAY_OPEN && s->events.new_media) {
        event_code = MEC_NEW_MEDIA;
        s->events.new_media = false;
    }

    buf[4] = event_code;
    buf[5] = media_status;

    /* These fields are reserved, just clear them. */
    buf[6] = 0;
    buf[7] = 0;

    return 8; /* We wrote to 4 extra bytes from the header */
}

static void cmd_get_event_status_notification(IDEState *s,
                                              uint8_t *buf)
{
    const uint8_t *packet = buf;

    struct {
        uint8_t opcode;
        uint8_t polled;        /* lsb bit is polled; others are reserved */
        uint8_t reserved2[2];
        uint8_t class;
        uint8_t reserved3[2];
        uint16_t len;
        uint8_t control;
    } __attribute__((packed)) *gesn_cdb;

    struct {
        uint16_t len;
        uint8_t notification_class;
        uint8_t supported_events;
    } __attribute((packed)) *gesn_event_header;

    enum notification_class_request_type {
        NCR_RESERVED1 = 1 << 0,
        NCR_OPERATIONAL_CHANGE = 1 << 1,
        NCR_POWER_MANAGEMENT = 1 << 2,
        NCR_EXTERNAL_REQUEST = 1 << 3,
        NCR_MEDIA = 1 << 4,
        NCR_MULTI_HOST = 1 << 5,
        NCR_DEVICE_BUSY = 1 << 6,
        NCR_RESERVED2 = 1 << 7,
    };
    enum event_notification_class_field {
        ENC_NO_EVENTS = 0,
        ENC_OPERATIONAL_CHANGE,
        ENC_POWER_MANAGEMENT,
        ENC_EXTERNAL_REQUEST,
        ENC_MEDIA,
        ENC_MULTIPLE_HOSTS,
        ENC_DEVICE_BUSY,
        ENC_RESERVED,
    };
    unsigned int max_len, used_len;

    gesn_cdb = (void *)packet;
    gesn_event_header = (void *)buf;

    max_len = be16_to_cpu(gesn_cdb->len);

    /* It is fine by the MMC spec to not support async mode operations */
    if (!(gesn_cdb->polled & 0x01)) { /* asynchronous mode */
        /* Only polling is supported, asynchronous mode is not. */
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_INV_FIELD_IN_CMD_PACKET);
        return;
    }

    /* polling mode operation */

    /*
     * These are the supported events.
     *
     * We currently only support requests of the 'media' type.
     */
    gesn_event_header->supported_events = NCR_MEDIA;

    /*
     * We use |= below to set the class field; other bits in this byte
     * are reserved now but this is useful to do if we have to use the
     * reserved fields later.
     */
    gesn_event_header->notification_class = 0;

    /*
     * Responses to requests are to be based on request priority.  The
     * notification_class_request_type enum above specifies the
     * priority: upper elements are higher prio than lower ones.
     */
    if (gesn_cdb->class & NCR_MEDIA) {
        gesn_event_header->notification_class |= ENC_MEDIA;
        used_len = event_status_media(s, buf);
    } else {
        gesn_event_header->notification_class = 0x80; /* No event available */
        used_len = sizeof(*gesn_event_header);
    }
    gesn_event_header->len = cpu_to_be16(used_len
                                         - sizeof(*gesn_event_header));
    ide_atapi_cmd_reply(s, used_len, max_len);
}

static void cmd_request_sense(IDEState *s, uint8_t *buf)
{
    int max_len = buf[4];

    memset(buf, 0, 18);
    buf[0] = 0x70 | (1 << 7);
    buf[2] = s->sense_key;
    buf[7] = 10;
    buf[12] = s->asc;

    if (s->sense_key == SENSE_UNIT_ATTENTION) {
        s->sense_key = SENSE_NONE;
    }

    ide_atapi_cmd_reply(s, 18, max_len);
}

static void cmd_inquiry(IDEState *s, uint8_t *buf)
{
    int max_len = buf[4];

    buf[0] = 0x05; /* CD-ROM */
    buf[1] = 0x80; /* removable */
    buf[2] = 0x00; /* ISO */
    buf[3] = 0x21; /* ATAPI-2 (XXX: put ATAPI-4 ?) */
    buf[4] = 31; /* additional length */
    buf[5] = 0; /* reserved */
    buf[6] = 0; /* reserved */
    buf[7] = 0; /* reserved */
    padstr8(buf + 8, 8, "QEMU");
    padstr8(buf + 16, 16, "QEMU DVD-ROM");
    padstr8(buf + 32, 4, s->version);
    ide_atapi_cmd_reply(s, 36, max_len);
}

static void cmd_get_configuration(IDEState *s, uint8_t *buf)
{
    uint32_t len;
    uint8_t index = 0;
    int max_len;

    /* only feature 0 is supported */
    if (buf[2] != 0 || buf[3] != 0) {
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_INV_FIELD_IN_CMD_PACKET);
        return;
    }

    /* XXX: could result in alignment problems in some architectures */
    max_len = ube16_to_cpu(buf + 7);

    /*
     * XXX: avoid overflow for io_buffer if max_len is bigger than
     *      the size of that buffer (dimensioned to max number of
     *      sectors to transfer at once)
     *
     *      Only a problem if the feature/profiles grow.
     */
    if (max_len > 512) {
        /* XXX: assume 1 sector */
        max_len = 512;
    }

    memset(buf, 0, max_len);
    /*
     * the number of sectors from the media tells us which profile
     * to use as current.  0 means there is no media
     */
    if (media_is_dvd(s)) {
        cpu_to_ube16(buf + 6, MMC_PROFILE_DVD_ROM);
    } else if (media_is_cd(s)) {
        cpu_to_ube16(buf + 6, MMC_PROFILE_CD_ROM);
    }

    buf[10] = 0x02 | 0x01; /* persistent and current */
    len = 12; /* headers: 8 + 4 */
    len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_DVD_ROM);
    len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_CD_ROM);
    cpu_to_ube32(buf, len - 4); /* data length */

    ide_atapi_cmd_reply(s, len, max_len);
}

static void cmd_mode_sense(IDEState *s, uint8_t *buf)
{
    int action, code;
    int max_len;

    if (buf[0] == GPCMD_MODE_SENSE_10) {
        max_len = ube16_to_cpu(buf + 7);
    } else {
        max_len = buf[4];
    }

    action = buf[2] >> 6;
    code = buf[2] & 0x3f;

    switch(action) {
    case 0: /* current values */
        switch(code) {
        case GPMODE_R_W_ERROR_PAGE: /* error recovery */
            cpu_to_ube16(&buf[0], 16 + 6);
            buf[2] = 0x70;
            buf[3] = 0;
            buf[4] = 0;
            buf[5] = 0;
            buf[6] = 0;
            buf[7] = 0;

            buf[8] = 0x01;
            buf[9] = 0x06;
            buf[10] = 0x00;
            buf[11] = 0x05;
            buf[12] = 0x00;
            buf[13] = 0x00;
            buf[14] = 0x00;
            buf[15] = 0x00;
            ide_atapi_cmd_reply(s, 16, max_len);
            break;
        case GPMODE_AUDIO_CTL_PAGE:
            cpu_to_ube16(&buf[0], 24 + 6);
            buf[2] = 0x70;
            buf[3] = 0;
            buf[4] = 0;
            buf[5] = 0;
            buf[6] = 0;
            buf[7] = 0;

            /* Fill with CDROM audio volume */
            buf[17] = 0;
            buf[19] = 0;
            buf[21] = 0;
            buf[23] = 0;

            ide_atapi_cmd_reply(s, 24, max_len);
            break;
        case GPMODE_CAPABILITIES_PAGE:
            cpu_to_ube16(&buf[0], 28 + 6);
            buf[2] = 0x70;
            buf[3] = 0;
            buf[4] = 0;
            buf[5] = 0;
            buf[6] = 0;
            buf[7] = 0;

            buf[8] = 0x2a;
            buf[9] = 0x12;
            buf[10] = 0x00;
            buf[11] = 0x00;

            /* Claim PLAY_AUDIO capability (0x01) since some Linux
               code checks for this to automount media. */
            buf[12] = 0x71;
            buf[13] = 3 << 5;
            buf[14] = (1 << 0) | (1 << 3) | (1 << 5);
            if (bdrv_is_locked(s->bs))
                buf[6] |= 1 << 1;
            buf[15] = 0x00;
            cpu_to_ube16(&buf[16], 706);
            buf[18] = 0;
            buf[19] = 2;
            cpu_to_ube16(&buf[20], 512);
            cpu_to_ube16(&buf[22], 706);
            buf[24] = 0;
            buf[25] = 0;
            buf[26] = 0;
            buf[27] = 0;
            ide_atapi_cmd_reply(s, 28, max_len);
            break;
        default:
            goto error_cmd;
        }
        break;
    case 1: /* changeable values */
        goto error_cmd;
    case 2: /* default values */
        goto error_cmd;
    default:
    case 3: /* saved values */
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_SAVING_PARAMETERS_NOT_SUPPORTED);
        break;
    }
    return;

error_cmd:
    ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, ASC_INV_FIELD_IN_CMD_PACKET);
}

static void cmd_test_unit_ready(IDEState *s, uint8_t *buf)
{
    /* Not Ready Conditions are already handled in ide_atapi_cmd(), so if we
     * come here, we know that it's ready. */
    ide_atapi_cmd_ok(s);
}

static void cmd_prevent_allow_medium_removal(IDEState *s, uint8_t* buf)
{
    bdrv_set_locked(s->bs, buf[4] & 1);
    ide_atapi_cmd_ok(s);
}

static void cmd_read(IDEState *s, uint8_t* buf)
{
    int nb_sectors, lba;

    if (buf[0] == GPCMD_READ_10) {
        nb_sectors = ube16_to_cpu(buf + 7);
    } else {
        nb_sectors = ube32_to_cpu(buf + 6);
    }

    lba = ube32_to_cpu(buf + 2);
    if (nb_sectors == 0) {
        ide_atapi_cmd_ok(s);
        return;
    }

    ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
}

static void cmd_read_cd(IDEState *s, uint8_t* buf)
{
    int nb_sectors, lba, transfer_request;

    nb_sectors = (buf[6] << 16) | (buf[7] << 8) | buf[8];
    lba = ube32_to_cpu(buf + 2);

    if (nb_sectors == 0) {
        ide_atapi_cmd_ok(s);
        return;
    }

    transfer_request = buf[9];
    switch(transfer_request & 0xf8) {
    case 0x00:
        /* nothing */
        ide_atapi_cmd_ok(s);
        break;
    case 0x10:
        /* normal read */
        ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
        break;
    case 0xf8:
        /* read all data */
        ide_atapi_cmd_read(s, lba, nb_sectors, 2352);
        break;
    default:
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_INV_FIELD_IN_CMD_PACKET);
        break;
    }
}

static void cmd_seek(IDEState *s, uint8_t* buf)
{
    unsigned int lba;
    uint64_t total_sectors = s->nb_sectors >> 2;

    lba = ube32_to_cpu(buf + 2);
    if (lba >= total_sectors) {
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, ASC_LOGICAL_BLOCK_OOR);
        return;
    }

    ide_atapi_cmd_ok(s);
}

static void cmd_start_stop_unit(IDEState *s, uint8_t* buf)
{
    int start, eject, sense, err = 0;
    start = buf[4] & 1;
    eject = (buf[4] >> 1) & 1;

    if (eject) {
        err = bdrv_eject(s->bs, !start);
    }

    switch (err) {
    case 0:
        ide_atapi_cmd_ok(s);
        break;
    case -EBUSY:
        sense = SENSE_NOT_READY;
        if (bdrv_is_inserted(s->bs)) {
            sense = SENSE_ILLEGAL_REQUEST;
        }
        ide_atapi_cmd_error(s, sense, ASC_MEDIA_REMOVAL_PREVENTED);
        break;
    default:
        ide_atapi_cmd_error(s, SENSE_NOT_READY, ASC_MEDIUM_NOT_PRESENT);
        break;
    }
}

static void cmd_mechanism_status(IDEState *s, uint8_t* buf)
{
    int max_len = ube16_to_cpu(buf + 8);

    cpu_to_ube16(buf, 0);
    /* no current LBA */
    buf[2] = 0;
    buf[3] = 0;
    buf[4] = 0;
    buf[5] = 1;
    cpu_to_ube16(buf + 6, 0);
    ide_atapi_cmd_reply(s, 8, max_len);
}

static void cmd_read_toc_pma_atip(IDEState *s, uint8_t* buf)
{
    int format, msf, start_track, len;
    int max_len;
    uint64_t total_sectors = s->nb_sectors >> 2;

    max_len = ube16_to_cpu(buf + 7);
    format = buf[9] >> 6;
    msf = (buf[1] >> 1) & 1;
    start_track = buf[6];

    switch(format) {
    case 0:
        len = cdrom_read_toc(total_sectors, buf, msf, start_track);
        if (len < 0)
            goto error_cmd;
        ide_atapi_cmd_reply(s, len, max_len);
        break;
    case 1:
        /* multi session : only a single session defined */
        memset(buf, 0, 12);
        buf[1] = 0x0a;
        buf[2] = 0x01;
        buf[3] = 0x01;
        ide_atapi_cmd_reply(s, 12, max_len);
        break;
    case 2:
        len = cdrom_read_toc_raw(total_sectors, buf, msf, start_track);
        if (len < 0)
            goto error_cmd;
        ide_atapi_cmd_reply(s, len, max_len);
        break;
    default:
    error_cmd:
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                            ASC_INV_FIELD_IN_CMD_PACKET);
    }
}

static void cmd_read_cdvd_capacity(IDEState *s, uint8_t* buf)
{
    uint64_t total_sectors = s->nb_sectors >> 2;

    /* NOTE: it is really the number of sectors minus 1 */
    cpu_to_ube32(buf, total_sectors - 1);
    cpu_to_ube32(buf + 4, 2048);
    ide_atapi_cmd_reply(s, 8, 8);
}

static void cmd_read_dvd_structure(IDEState *s, uint8_t* buf)
{
    int max_len;
    int media = buf[1];
    int format = buf[7];
    int ret;

    max_len = ube16_to_cpu(buf + 8);

    if (format < 0xff) {
        if (media_is_cd(s)) {
            ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                                ASC_INCOMPATIBLE_FORMAT);
            return;
        } else if (!media_present(s)) {
            ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                                ASC_INV_FIELD_IN_CMD_PACKET);
            return;
        }
    }

    memset(buf, 0, max_len > IDE_DMA_BUF_SECTORS * 512 + 4 ?
           IDE_DMA_BUF_SECTORS * 512 + 4 : max_len);

    switch (format) {
        case 0x00 ... 0x7f:
        case 0xff:
            if (media == 0) {
                ret = ide_dvd_read_structure(s, format, buf, buf);

                if (ret < 0) {
                    ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, -ret);
                } else {
                    ide_atapi_cmd_reply(s, ret, max_len);
                }

                break;
            }
            /* TODO: BD support, fall through for now */

        /* Generic disk structures */
        case 0x80: /* TODO: AACS volume identifier */
        case 0x81: /* TODO: AACS media serial number */
        case 0x82: /* TODO: AACS media identifier */
        case 0x83: /* TODO: AACS media key block */
        case 0x90: /* TODO: List of recognized format layers */
        case 0xc0: /* TODO: Write protection status */
        default:
            ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                                ASC_INV_FIELD_IN_CMD_PACKET);
            break;
    }
}

static void cmd_set_speed(IDEState *s, uint8_t* buf)
{
    ide_atapi_cmd_ok(s);
}

enum {
    /*
     * Only commands flagged as ALLOW_UA are allowed to run under a
     * unit attention condition. (See MMC-5, section 4.1.6.1)
     */
    ALLOW_UA = 0x01,

    /*
     * Commands flagged with CHECK_READY can only execute if a medium is present.
     * Otherwise they report the Not Ready Condition. (See MMC-5, section
     * 4.1.8)
     */
    CHECK_READY = 0x02,
};

static const struct {
    void (*handler)(IDEState *s, uint8_t *buf);
    int flags;
} atapi_cmd_table[0x100] = {
    [ 0x00 ] = { cmd_test_unit_ready,               CHECK_READY },
    [ 0x03 ] = { cmd_request_sense,                 ALLOW_UA },
    [ 0x12 ] = { cmd_inquiry,                       ALLOW_UA },
    [ 0x1a ] = { cmd_mode_sense, /* (6) */          0 },
    [ 0x1b ] = { cmd_start_stop_unit,               0 },
    [ 0x1e ] = { cmd_prevent_allow_medium_removal,  0 },
    [ 0x25 ] = { cmd_read_cdvd_capacity,            CHECK_READY },
    [ 0x28 ] = { cmd_read, /* (10) */               0 },
    [ 0x2b ] = { cmd_seek,                          CHECK_READY },
    [ 0x43 ] = { cmd_read_toc_pma_atip,             CHECK_READY },
    [ 0x46 ] = { cmd_get_configuration,             ALLOW_UA },
    [ 0x4a ] = { cmd_get_event_status_notification, ALLOW_UA },
    [ 0x5a ] = { cmd_mode_sense, /* (10) */         0 },
    [ 0xa8 ] = { cmd_read, /* (12) */               0 },
    [ 0xad ] = { cmd_read_dvd_structure,            0 },
    [ 0xbb ] = { cmd_set_speed,                     0 },
    [ 0xbd ] = { cmd_mechanism_status,              0 },
    [ 0xbe ] = { cmd_read_cd,                       0 },
};

void ide_atapi_cmd(IDEState *s)
{
    uint8_t *buf;

    buf = s->io_buffer;
#ifdef DEBUG_IDE_ATAPI
    {
        int i;
        printf("ATAPI limit=0x%x packet:", s->lcyl | (s->hcyl << 8));
        for(i = 0; i < ATAPI_PACKET_SIZE; i++) {
            printf(" %02x", buf[i]);
        }
        printf("\n");
    }
#endif
    /*
     * If there's a UNIT_ATTENTION condition pending, only command flagged with
     * ALLOW_UA are allowed to complete. with other commands getting a CHECK
     * condition response unless a higher priority status, defined by the drive
     * here, is pending.
     */
    if (s->sense_key == SENSE_UNIT_ATTENTION &&
        !(atapi_cmd_table[s->io_buffer[0]].flags & ALLOW_UA)) {
        ide_atapi_cmd_check_status(s);
        return;
    }
    /*
     * When a CD gets changed, we have to report an ejected state and
     * then a loaded state to guests so that they detect tray
     * open/close and media change events.  Guests that do not use
     * GET_EVENT_STATUS_NOTIFICATION to detect such tray open/close
     * states rely on this behavior.
     */
    if (bdrv_is_inserted(s->bs) && s->cdrom_changed) {
        ide_atapi_cmd_error(s, SENSE_NOT_READY, ASC_MEDIUM_NOT_PRESENT);

        s->cdrom_changed = 0;
        s->sense_key = SENSE_UNIT_ATTENTION;
        s->asc = ASC_MEDIUM_MAY_HAVE_CHANGED;
        return;
    }

    /* Report a Not Ready condition if appropriate for the command */
    if ((atapi_cmd_table[s->io_buffer[0]].flags & CHECK_READY) &&
        (!media_present(s) || !bdrv_is_inserted(s->bs)))
    {
        ide_atapi_cmd_error(s, SENSE_NOT_READY, ASC_MEDIUM_NOT_PRESENT);
        return;
    }

    /* Execute the command */
    if (atapi_cmd_table[s->io_buffer[0]].handler) {
        atapi_cmd_table[s->io_buffer[0]].handler(s, buf);
        return;
    }

    ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, ASC_ILLEGAL_OPCODE);
}