xref: /openbmc/qemu/hw/ide/atapi.c (revision 4b4629d9)
1 /*
2  * QEMU ATAPI Emulation
3  *
4  * Copyright (c) 2003 Fabrice Bellard
5  * Copyright (c) 2006 Openedhand Ltd.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "hw/ide/internal.h"
28 #include "hw/scsi/scsi.h"
29 #include "sysemu/block-backend.h"
30 
31 #define ATAPI_SECTOR_BITS (2 + BDRV_SECTOR_BITS)
32 #define ATAPI_SECTOR_SIZE (1 << ATAPI_SECTOR_BITS)
33 
34 static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret);
35 
36 static void padstr8(uint8_t *buf, int buf_size, const char *src)
37 {
38     int i;
39     for(i = 0; i < buf_size; i++) {
40         if (*src)
41             buf[i] = *src++;
42         else
43             buf[i] = ' ';
44     }
45 }
46 
47 static inline void cpu_to_ube16(uint8_t *buf, int val)
48 {
49     buf[0] = val >> 8;
50     buf[1] = val & 0xff;
51 }
52 
53 static inline void cpu_to_ube32(uint8_t *buf, unsigned int val)
54 {
55     buf[0] = val >> 24;
56     buf[1] = val >> 16;
57     buf[2] = val >> 8;
58     buf[3] = val & 0xff;
59 }
60 
61 static inline int ube16_to_cpu(const uint8_t *buf)
62 {
63     return (buf[0] << 8) | buf[1];
64 }
65 
66 static inline int ube32_to_cpu(const uint8_t *buf)
67 {
68     return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
69 }
70 
71 static void lba_to_msf(uint8_t *buf, int lba)
72 {
73     lba += 150;
74     buf[0] = (lba / 75) / 60;
75     buf[1] = (lba / 75) % 60;
76     buf[2] = lba % 75;
77 }
78 
79 static inline int media_present(IDEState *s)
80 {
81     return !s->tray_open && s->nb_sectors > 0;
82 }
83 
84 /* XXX: DVDs that could fit on a CD will be reported as a CD */
85 static inline int media_is_dvd(IDEState *s)
86 {
87     return (media_present(s) && s->nb_sectors > CD_MAX_SECTORS);
88 }
89 
90 static inline int media_is_cd(IDEState *s)
91 {
92     return (media_present(s) && s->nb_sectors <= CD_MAX_SECTORS);
93 }
94 
95 static void cd_data_to_raw(uint8_t *buf, int lba)
96 {
97     /* sync bytes */
98     buf[0] = 0x00;
99     memset(buf + 1, 0xff, 10);
100     buf[11] = 0x00;
101     buf += 12;
102     /* MSF */
103     lba_to_msf(buf, lba);
104     buf[3] = 0x01; /* mode 1 data */
105     buf += 4;
106     /* data */
107     buf += 2048;
108     /* XXX: ECC not computed */
109     memset(buf, 0, 288);
110 }
111 
112 static int
113 cd_read_sector_sync(IDEState *s)
114 {
115     int ret;
116     block_acct_start(blk_get_stats(s->blk), &s->acct,
117                      ATAPI_SECTOR_SIZE, BLOCK_ACCT_READ);
118 
119 #ifdef DEBUG_IDE_ATAPI
120     printf("cd_read_sector_sync: lba=%d\n", s->lba);
121 #endif
122 
123     switch (s->cd_sector_size) {
124     case 2048:
125         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
126                         s->io_buffer, ATAPI_SECTOR_SIZE);
127         break;
128     case 2352:
129         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
130                         s->io_buffer + 16, ATAPI_SECTOR_SIZE);
131         if (ret >= 0) {
132             cd_data_to_raw(s->io_buffer, s->lba);
133         }
134         break;
135     default:
136         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_READ);
137         return -EIO;
138     }
139 
140     if (ret < 0) {
141         block_acct_failed(blk_get_stats(s->blk), &s->acct);
142     } else {
143         block_acct_done(blk_get_stats(s->blk), &s->acct);
144         s->lba++;
145         s->io_buffer_index = 0;
146     }
147 
148     return ret;
149 }
150 
151 static void cd_read_sector_cb(void *opaque, int ret)
152 {
153     IDEState *s = opaque;
154 
155 #ifdef DEBUG_IDE_ATAPI
156     printf("cd_read_sector_cb: lba=%d ret=%d\n", s->lba, ret);
157 #endif
158 
159     if (ret < 0) {
160         block_acct_failed(blk_get_stats(s->blk), &s->acct);
161         ide_atapi_io_error(s, ret);
162         return;
163     }
164 
165     block_acct_done(blk_get_stats(s->blk), &s->acct);
166 
167     if (s->cd_sector_size == 2352) {
168         cd_data_to_raw(s->io_buffer, s->lba);
169     }
170 
171     s->lba++;
172     s->io_buffer_index = 0;
173     s->status &= ~BUSY_STAT;
174 
175     ide_atapi_cmd_reply_end(s);
176 }
177 
178 static int cd_read_sector(IDEState *s)
179 {
180     if (s->cd_sector_size != 2048 && s->cd_sector_size != 2352) {
181         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_READ);
182         return -EINVAL;
183     }
184 
185     s->iov.iov_base = (s->cd_sector_size == 2352) ?
186                       s->io_buffer + 16 : s->io_buffer;
187 
188     s->iov.iov_len = ATAPI_SECTOR_SIZE;
189     qemu_iovec_init_external(&s->qiov, &s->iov, 1);
190 
191 #ifdef DEBUG_IDE_ATAPI
192     printf("cd_read_sector: lba=%d\n", s->lba);
193 #endif
194 
195     block_acct_start(blk_get_stats(s->blk), &s->acct,
196                      ATAPI_SECTOR_SIZE, BLOCK_ACCT_READ);
197 
198     ide_buffered_readv(s, (int64_t)s->lba << 2, &s->qiov, 4,
199                        cd_read_sector_cb, s);
200 
201     s->status |= BUSY_STAT;
202     return 0;
203 }
204 
205 void ide_atapi_cmd_ok(IDEState *s)
206 {
207     s->error = 0;
208     s->status = READY_STAT | SEEK_STAT;
209     s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
210     ide_transfer_stop(s);
211     ide_set_irq(s->bus);
212 }
213 
214 void ide_atapi_cmd_error(IDEState *s, int sense_key, int asc)
215 {
216 #ifdef DEBUG_IDE_ATAPI
217     printf("atapi_cmd_error: sense=0x%x asc=0x%x\n", sense_key, asc);
218 #endif
219     s->error = sense_key << 4;
220     s->status = READY_STAT | ERR_STAT;
221     s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
222     s->sense_key = sense_key;
223     s->asc = asc;
224     ide_transfer_stop(s);
225     ide_set_irq(s->bus);
226 }
227 
228 void ide_atapi_io_error(IDEState *s, int ret)
229 {
230     /* XXX: handle more errors */
231     if (ret == -ENOMEDIUM) {
232         ide_atapi_cmd_error(s, NOT_READY,
233                             ASC_MEDIUM_NOT_PRESENT);
234     } else {
235         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
236                             ASC_LOGICAL_BLOCK_OOR);
237     }
238 }
239 
240 static uint16_t atapi_byte_count_limit(IDEState *s)
241 {
242     uint16_t bcl;
243 
244     bcl = s->lcyl | (s->hcyl << 8);
245     if (bcl == 0xffff) {
246         return 0xfffe;
247     }
248     return bcl;
249 }
250 
251 /* The whole ATAPI transfer logic is handled in this function */
252 void ide_atapi_cmd_reply_end(IDEState *s)
253 {
254     int byte_count_limit, size, ret;
255 #ifdef DEBUG_IDE_ATAPI
256     printf("reply: tx_size=%d elem_tx_size=%d index=%d\n",
257            s->packet_transfer_size,
258            s->elementary_transfer_size,
259            s->io_buffer_index);
260 #endif
261     if (s->packet_transfer_size <= 0) {
262         /* end of transfer */
263         ide_atapi_cmd_ok(s);
264         ide_set_irq(s->bus);
265 #ifdef DEBUG_IDE_ATAPI
266         printf("end of transfer, status=0x%x\n", s->status);
267 #endif
268     } else {
269         /* see if a new sector must be read */
270         if (s->lba != -1 && s->io_buffer_index >= s->cd_sector_size) {
271             if (!s->elementary_transfer_size) {
272                 ret = cd_read_sector(s);
273                 if (ret < 0) {
274                     ide_atapi_io_error(s, ret);
275                 }
276                 return;
277             } else {
278                 /* rebuffering within an elementary transfer is
279                  * only possible with a sync request because we
280                  * end up with a race condition otherwise */
281                 ret = cd_read_sector_sync(s);
282                 if (ret < 0) {
283                     ide_atapi_io_error(s, ret);
284                     return;
285                 }
286             }
287         }
288         if (s->elementary_transfer_size > 0) {
289             /* there are some data left to transmit in this elementary
290                transfer */
291             size = s->cd_sector_size - s->io_buffer_index;
292             if (size > s->elementary_transfer_size)
293                 size = s->elementary_transfer_size;
294             s->packet_transfer_size -= size;
295             s->elementary_transfer_size -= size;
296             s->io_buffer_index += size;
297             ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
298                                size, ide_atapi_cmd_reply_end);
299         } else {
300             /* a new transfer is needed */
301             s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
302             byte_count_limit = atapi_byte_count_limit(s);
303 #ifdef DEBUG_IDE_ATAPI
304             printf("byte_count_limit=%d\n", byte_count_limit);
305 #endif
306             size = s->packet_transfer_size;
307             if (size > byte_count_limit) {
308                 /* byte count limit must be even if this case */
309                 if (byte_count_limit & 1)
310                     byte_count_limit--;
311                 size = byte_count_limit;
312             }
313             s->lcyl = size;
314             s->hcyl = size >> 8;
315             s->elementary_transfer_size = size;
316             /* we cannot transmit more than one sector at a time */
317             if (s->lba != -1) {
318                 if (size > (s->cd_sector_size - s->io_buffer_index))
319                     size = (s->cd_sector_size - s->io_buffer_index);
320             }
321             s->packet_transfer_size -= size;
322             s->elementary_transfer_size -= size;
323             s->io_buffer_index += size;
324             ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
325                                size, ide_atapi_cmd_reply_end);
326             ide_set_irq(s->bus);
327 #ifdef DEBUG_IDE_ATAPI
328             printf("status=0x%x\n", s->status);
329 #endif
330         }
331     }
332 }
333 
334 /* send a reply of 'size' bytes in s->io_buffer to an ATAPI command */
335 static void ide_atapi_cmd_reply(IDEState *s, int size, int max_size)
336 {
337     if (size > max_size)
338         size = max_size;
339     s->lba = -1; /* no sector read */
340     s->packet_transfer_size = size;
341     s->io_buffer_size = size;    /* dma: send the reply data as one chunk */
342     s->elementary_transfer_size = 0;
343 
344     if (s->atapi_dma) {
345         block_acct_start(blk_get_stats(s->blk), &s->acct, size,
346                          BLOCK_ACCT_READ);
347         s->status = READY_STAT | SEEK_STAT | DRQ_STAT;
348         ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
349     } else {
350         s->status = READY_STAT | SEEK_STAT;
351         s->io_buffer_index = 0;
352         ide_atapi_cmd_reply_end(s);
353     }
354 }
355 
356 /* start a CD-CDROM read command */
357 static void ide_atapi_cmd_read_pio(IDEState *s, int lba, int nb_sectors,
358                                    int sector_size)
359 {
360     s->lba = lba;
361     s->packet_transfer_size = nb_sectors * sector_size;
362     s->elementary_transfer_size = 0;
363     s->io_buffer_index = sector_size;
364     s->cd_sector_size = sector_size;
365 
366     ide_atapi_cmd_reply_end(s);
367 }
368 
369 static void ide_atapi_cmd_check_status(IDEState *s)
370 {
371 #ifdef DEBUG_IDE_ATAPI
372     printf("atapi_cmd_check_status\n");
373 #endif
374     s->error = MC_ERR | (UNIT_ATTENTION << 4);
375     s->status = ERR_STAT;
376     s->nsector = 0;
377     ide_set_irq(s->bus);
378 }
379 /* ATAPI DMA support */
380 
381 static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret)
382 {
383     IDEState *s = opaque;
384     int data_offset, n;
385 
386     if (ret < 0) {
387         if (ide_handle_rw_error(s, -ret, ide_dma_cmd_to_retry(s->dma_cmd))) {
388             if (s->bus->error_status) {
389                 return;
390             }
391             goto eot;
392         }
393     }
394 
395     if (s->io_buffer_size > 0) {
396         /*
397          * For a cdrom read sector command (s->lba != -1),
398          * adjust the lba for the next s->io_buffer_size chunk
399          * and dma the current chunk.
400          * For a command != read (s->lba == -1), just transfer
401          * the reply data.
402          */
403         if (s->lba != -1) {
404             if (s->cd_sector_size == 2352) {
405                 n = 1;
406                 cd_data_to_raw(s->io_buffer, s->lba);
407             } else {
408                 n = s->io_buffer_size >> 11;
409             }
410             s->lba += n;
411         }
412         s->packet_transfer_size -= s->io_buffer_size;
413         if (s->bus->dma->ops->rw_buf(s->bus->dma, 1) == 0)
414             goto eot;
415     }
416 
417     if (s->packet_transfer_size <= 0) {
418         s->status = READY_STAT | SEEK_STAT;
419         s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
420         ide_set_irq(s->bus);
421         goto eot;
422     }
423 
424     s->io_buffer_index = 0;
425     if (s->cd_sector_size == 2352) {
426         n = 1;
427         s->io_buffer_size = s->cd_sector_size;
428         data_offset = 16;
429     } else {
430         n = s->packet_transfer_size >> 11;
431         if (n > (IDE_DMA_BUF_SECTORS / 4))
432             n = (IDE_DMA_BUF_SECTORS / 4);
433         s->io_buffer_size = n * 2048;
434         data_offset = 0;
435     }
436 #ifdef DEBUG_AIO
437     printf("aio_read_cd: lba=%u n=%d\n", s->lba, n);
438 #endif
439 
440     s->bus->dma->iov.iov_base = (void *)(s->io_buffer + data_offset);
441     s->bus->dma->iov.iov_len = n * ATAPI_SECTOR_SIZE;
442     qemu_iovec_init_external(&s->bus->dma->qiov, &s->bus->dma->iov, 1);
443 
444     s->bus->dma->aiocb = ide_buffered_readv(s, (int64_t)s->lba << 2,
445                                             &s->bus->dma->qiov, n * 4,
446                                             ide_atapi_cmd_read_dma_cb, s);
447     return;
448 
449 eot:
450     if (ret < 0) {
451         block_acct_failed(blk_get_stats(s->blk), &s->acct);
452     } else {
453         block_acct_done(blk_get_stats(s->blk), &s->acct);
454     }
455     ide_set_inactive(s, false);
456 }
457 
458 /* start a CD-CDROM read command with DMA */
459 /* XXX: test if DMA is available */
460 static void ide_atapi_cmd_read_dma(IDEState *s, int lba, int nb_sectors,
461                                    int sector_size)
462 {
463     s->lba = lba;
464     s->packet_transfer_size = nb_sectors * sector_size;
465     s->io_buffer_size = 0;
466     s->cd_sector_size = sector_size;
467 
468     block_acct_start(blk_get_stats(s->blk), &s->acct, s->packet_transfer_size,
469                      BLOCK_ACCT_READ);
470 
471     /* XXX: check if BUSY_STAT should be set */
472     s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
473     ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
474 }
475 
476 static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors,
477                                int sector_size)
478 {
479 #ifdef DEBUG_IDE_ATAPI
480     printf("read %s: LBA=%d nb_sectors=%d\n", s->atapi_dma ? "dma" : "pio",
481         lba, nb_sectors);
482 #endif
483     if (s->atapi_dma) {
484         ide_atapi_cmd_read_dma(s, lba, nb_sectors, sector_size);
485     } else {
486         ide_atapi_cmd_read_pio(s, lba, nb_sectors, sector_size);
487     }
488 }
489 
490 void ide_atapi_dma_restart(IDEState *s)
491 {
492     /*
493      * At this point we can just re-evaluate the packet command and start over.
494      * The presence of ->dma_cb callback in the pre_save ensures that the packet
495      * command has been completely sent and we can safely restart command.
496      */
497     s->unit = s->bus->retry_unit;
498     s->bus->dma->ops->restart_dma(s->bus->dma);
499     ide_atapi_cmd(s);
500 }
501 
502 static inline uint8_t ide_atapi_set_profile(uint8_t *buf, uint8_t *index,
503                                             uint16_t profile)
504 {
505     uint8_t *buf_profile = buf + 12; /* start of profiles */
506 
507     buf_profile += ((*index) * 4); /* start of indexed profile */
508     cpu_to_ube16 (buf_profile, profile);
509     buf_profile[2] = ((buf_profile[0] == buf[6]) && (buf_profile[1] == buf[7]));
510 
511     /* each profile adds 4 bytes to the response */
512     (*index)++;
513     buf[11] += 4; /* Additional Length */
514 
515     return 4;
516 }
517 
518 static int ide_dvd_read_structure(IDEState *s, int format,
519                                   const uint8_t *packet, uint8_t *buf)
520 {
521     switch (format) {
522         case 0x0: /* Physical format information */
523             {
524                 int layer = packet[6];
525                 uint64_t total_sectors;
526 
527                 if (layer != 0)
528                     return -ASC_INV_FIELD_IN_CMD_PACKET;
529 
530                 total_sectors = s->nb_sectors >> 2;
531                 if (total_sectors == 0) {
532                     return -ASC_MEDIUM_NOT_PRESENT;
533                 }
534 
535                 buf[4] = 1;   /* DVD-ROM, part version 1 */
536                 buf[5] = 0xf; /* 120mm disc, minimum rate unspecified */
537                 buf[6] = 1;   /* one layer, read-only (per MMC-2 spec) */
538                 buf[7] = 0;   /* default densities */
539 
540                 /* FIXME: 0x30000 per spec? */
541                 cpu_to_ube32(buf + 8, 0); /* start sector */
542                 cpu_to_ube32(buf + 12, total_sectors - 1); /* end sector */
543                 cpu_to_ube32(buf + 16, total_sectors - 1); /* l0 end sector */
544 
545                 /* Size of buffer, not including 2 byte size field */
546                 stw_be_p(buf, 2048 + 2);
547 
548                 /* 2k data + 4 byte header */
549                 return (2048 + 4);
550             }
551 
552         case 0x01: /* DVD copyright information */
553             buf[4] = 0; /* no copyright data */
554             buf[5] = 0; /* no region restrictions */
555 
556             /* Size of buffer, not including 2 byte size field */
557             stw_be_p(buf, 4 + 2);
558 
559             /* 4 byte header + 4 byte data */
560             return (4 + 4);
561 
562         case 0x03: /* BCA information - invalid field for no BCA info */
563             return -ASC_INV_FIELD_IN_CMD_PACKET;
564 
565         case 0x04: /* DVD disc manufacturing information */
566             /* Size of buffer, not including 2 byte size field */
567             stw_be_p(buf, 2048 + 2);
568 
569             /* 2k data + 4 byte header */
570             return (2048 + 4);
571 
572         case 0xff:
573             /*
574              * This lists all the command capabilities above.  Add new ones
575              * in order and update the length and buffer return values.
576              */
577 
578             buf[4] = 0x00; /* Physical format */
579             buf[5] = 0x40; /* Not writable, is readable */
580             stw_be_p(buf + 6, 2048 + 4);
581 
582             buf[8] = 0x01; /* Copyright info */
583             buf[9] = 0x40; /* Not writable, is readable */
584             stw_be_p(buf + 10, 4 + 4);
585 
586             buf[12] = 0x03; /* BCA info */
587             buf[13] = 0x40; /* Not writable, is readable */
588             stw_be_p(buf + 14, 188 + 4);
589 
590             buf[16] = 0x04; /* Manufacturing info */
591             buf[17] = 0x40; /* Not writable, is readable */
592             stw_be_p(buf + 18, 2048 + 4);
593 
594             /* Size of buffer, not including 2 byte size field */
595             stw_be_p(buf, 16 + 2);
596 
597             /* data written + 4 byte header */
598             return (16 + 4);
599 
600         default: /* TODO: formats beyond DVD-ROM requires */
601             return -ASC_INV_FIELD_IN_CMD_PACKET;
602     }
603 }
604 
605 static unsigned int event_status_media(IDEState *s,
606                                        uint8_t *buf)
607 {
608     uint8_t event_code, media_status;
609 
610     media_status = 0;
611     if (s->tray_open) {
612         media_status = MS_TRAY_OPEN;
613     } else if (blk_is_inserted(s->blk)) {
614         media_status = MS_MEDIA_PRESENT;
615     }
616 
617     /* Event notification descriptor */
618     event_code = MEC_NO_CHANGE;
619     if (media_status != MS_TRAY_OPEN) {
620         if (s->events.new_media) {
621             event_code = MEC_NEW_MEDIA;
622             s->events.new_media = false;
623         } else if (s->events.eject_request) {
624             event_code = MEC_EJECT_REQUESTED;
625             s->events.eject_request = false;
626         }
627     }
628 
629     buf[4] = event_code;
630     buf[5] = media_status;
631 
632     /* These fields are reserved, just clear them. */
633     buf[6] = 0;
634     buf[7] = 0;
635 
636     return 8; /* We wrote to 4 extra bytes from the header */
637 }
638 
639 static void cmd_get_event_status_notification(IDEState *s,
640                                               uint8_t *buf)
641 {
642     const uint8_t *packet = buf;
643 
644     struct {
645         uint8_t opcode;
646         uint8_t polled;        /* lsb bit is polled; others are reserved */
647         uint8_t reserved2[2];
648         uint8_t class;
649         uint8_t reserved3[2];
650         uint16_t len;
651         uint8_t control;
652     } QEMU_PACKED *gesn_cdb;
653 
654     struct {
655         uint16_t len;
656         uint8_t notification_class;
657         uint8_t supported_events;
658     } QEMU_PACKED *gesn_event_header;
659     unsigned int max_len, used_len;
660 
661     gesn_cdb = (void *)packet;
662     gesn_event_header = (void *)buf;
663 
664     max_len = be16_to_cpu(gesn_cdb->len);
665 
666     /* It is fine by the MMC spec to not support async mode operations */
667     if (!(gesn_cdb->polled & 0x01)) { /* asynchronous mode */
668         /* Only polling is supported, asynchronous mode is not. */
669         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
670                             ASC_INV_FIELD_IN_CMD_PACKET);
671         return;
672     }
673 
674     /* polling mode operation */
675 
676     /*
677      * These are the supported events.
678      *
679      * We currently only support requests of the 'media' type.
680      * Notification class requests and supported event classes are bitmasks,
681      * but they are build from the same values as the "notification class"
682      * field.
683      */
684     gesn_event_header->supported_events = 1 << GESN_MEDIA;
685 
686     /*
687      * We use |= below to set the class field; other bits in this byte
688      * are reserved now but this is useful to do if we have to use the
689      * reserved fields later.
690      */
691     gesn_event_header->notification_class = 0;
692 
693     /*
694      * Responses to requests are to be based on request priority.  The
695      * notification_class_request_type enum above specifies the
696      * priority: upper elements are higher prio than lower ones.
697      */
698     if (gesn_cdb->class & (1 << GESN_MEDIA)) {
699         gesn_event_header->notification_class |= GESN_MEDIA;
700         used_len = event_status_media(s, buf);
701     } else {
702         gesn_event_header->notification_class = 0x80; /* No event available */
703         used_len = sizeof(*gesn_event_header);
704     }
705     gesn_event_header->len = cpu_to_be16(used_len
706                                          - sizeof(*gesn_event_header));
707     ide_atapi_cmd_reply(s, used_len, max_len);
708 }
709 
710 static void cmd_request_sense(IDEState *s, uint8_t *buf)
711 {
712     int max_len = buf[4];
713 
714     memset(buf, 0, 18);
715     buf[0] = 0x70 | (1 << 7);
716     buf[2] = s->sense_key;
717     buf[7] = 10;
718     buf[12] = s->asc;
719 
720     if (s->sense_key == UNIT_ATTENTION) {
721         s->sense_key = NO_SENSE;
722     }
723 
724     ide_atapi_cmd_reply(s, 18, max_len);
725 }
726 
727 static void cmd_inquiry(IDEState *s, uint8_t *buf)
728 {
729     uint8_t page_code = buf[2];
730     int max_len = buf[4];
731 
732     unsigned idx = 0;
733     unsigned size_idx;
734     unsigned preamble_len;
735 
736     /* If the EVPD (Enable Vital Product Data) bit is set in byte 1,
737      * we are being asked for a specific page of info indicated by byte 2. */
738     if (buf[1] & 0x01) {
739         preamble_len = 4;
740         size_idx = 3;
741 
742         buf[idx++] = 0x05;      /* CD-ROM */
743         buf[idx++] = page_code; /* Page Code */
744         buf[idx++] = 0x00;      /* reserved */
745         idx++;                  /* length (set later) */
746 
747         switch (page_code) {
748         case 0x00:
749             /* Supported Pages: List of supported VPD responses. */
750             buf[idx++] = 0x00; /* 0x00: Supported Pages, and: */
751             buf[idx++] = 0x83; /* 0x83: Device Identification. */
752             break;
753 
754         case 0x83:
755             /* Device Identification. Each entry is optional, but the entries
756              * included here are modeled after libata's VPD responses.
757              * If the response is given, at least one entry must be present. */
758 
759             /* Entry 1: Serial */
760             if (idx + 24 > max_len) {
761                 /* Not enough room for even the first entry: */
762                 /* 4 byte header + 20 byte string */
763                 ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
764                                     ASC_DATA_PHASE_ERROR);
765                 return;
766             }
767             buf[idx++] = 0x02; /* Ascii */
768             buf[idx++] = 0x00; /* Vendor Specific */
769             buf[idx++] = 0x00;
770             buf[idx++] = 20;   /* Remaining length */
771             padstr8(buf + idx, 20, s->drive_serial_str);
772             idx += 20;
773 
774             /* Entry 2: Drive Model and Serial */
775             if (idx + 72 > max_len) {
776                 /* 4 (header) + 8 (vendor) + 60 (model & serial) */
777                 goto out;
778             }
779             buf[idx++] = 0x02; /* Ascii */
780             buf[idx++] = 0x01; /* T10 Vendor */
781             buf[idx++] = 0x00;
782             buf[idx++] = 68;
783             padstr8(buf + idx, 8, "ATA"); /* Generic T10 vendor */
784             idx += 8;
785             padstr8(buf + idx, 40, s->drive_model_str);
786             idx += 40;
787             padstr8(buf + idx, 20, s->drive_serial_str);
788             idx += 20;
789 
790             /* Entry 3: WWN */
791             if (s->wwn && (idx + 12 <= max_len)) {
792                 /* 4 byte header + 8 byte wwn */
793                 buf[idx++] = 0x01; /* Binary */
794                 buf[idx++] = 0x03; /* NAA */
795                 buf[idx++] = 0x00;
796                 buf[idx++] = 0x08;
797                 stq_be_p(&buf[idx], s->wwn);
798                 idx += 8;
799             }
800             break;
801 
802         default:
803             /* SPC-3, revision 23 sec. 6.4 */
804             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
805                                 ASC_INV_FIELD_IN_CMD_PACKET);
806             return;
807         }
808     } else {
809         preamble_len = 5;
810         size_idx = 4;
811 
812         buf[0] = 0x05; /* CD-ROM */
813         buf[1] = 0x80; /* removable */
814         buf[2] = 0x00; /* ISO */
815         buf[3] = 0x21; /* ATAPI-2 (XXX: put ATAPI-4 ?) */
816         /* buf[size_idx] set below. */
817         buf[5] = 0;    /* reserved */
818         buf[6] = 0;    /* reserved */
819         buf[7] = 0;    /* reserved */
820         padstr8(buf + 8, 8, "QEMU");
821         padstr8(buf + 16, 16, "QEMU DVD-ROM");
822         padstr8(buf + 32, 4, s->version);
823         idx = 36;
824     }
825 
826  out:
827     buf[size_idx] = idx - preamble_len;
828     ide_atapi_cmd_reply(s, idx, max_len);
829 }
830 
831 static void cmd_get_configuration(IDEState *s, uint8_t *buf)
832 {
833     uint32_t len;
834     uint8_t index = 0;
835     int max_len;
836 
837     /* only feature 0 is supported */
838     if (buf[2] != 0 || buf[3] != 0) {
839         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
840                             ASC_INV_FIELD_IN_CMD_PACKET);
841         return;
842     }
843 
844     /* XXX: could result in alignment problems in some architectures */
845     max_len = ube16_to_cpu(buf + 7);
846 
847     /*
848      * XXX: avoid overflow for io_buffer if max_len is bigger than
849      *      the size of that buffer (dimensioned to max number of
850      *      sectors to transfer at once)
851      *
852      *      Only a problem if the feature/profiles grow.
853      */
854     if (max_len > 512) {
855         /* XXX: assume 1 sector */
856         max_len = 512;
857     }
858 
859     memset(buf, 0, max_len);
860     /*
861      * the number of sectors from the media tells us which profile
862      * to use as current.  0 means there is no media
863      */
864     if (media_is_dvd(s)) {
865         cpu_to_ube16(buf + 6, MMC_PROFILE_DVD_ROM);
866     } else if (media_is_cd(s)) {
867         cpu_to_ube16(buf + 6, MMC_PROFILE_CD_ROM);
868     }
869 
870     buf[10] = 0x02 | 0x01; /* persistent and current */
871     len = 12; /* headers: 8 + 4 */
872     len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_DVD_ROM);
873     len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_CD_ROM);
874     cpu_to_ube32(buf, len - 4); /* data length */
875 
876     ide_atapi_cmd_reply(s, len, max_len);
877 }
878 
879 static void cmd_mode_sense(IDEState *s, uint8_t *buf)
880 {
881     int action, code;
882     int max_len;
883 
884     max_len = ube16_to_cpu(buf + 7);
885     action = buf[2] >> 6;
886     code = buf[2] & 0x3f;
887 
888     switch(action) {
889     case 0: /* current values */
890         switch(code) {
891         case MODE_PAGE_R_W_ERROR: /* error recovery */
892             cpu_to_ube16(&buf[0], 16 - 2);
893             buf[2] = 0x70;
894             buf[3] = 0;
895             buf[4] = 0;
896             buf[5] = 0;
897             buf[6] = 0;
898             buf[7] = 0;
899 
900             buf[8] = MODE_PAGE_R_W_ERROR;
901             buf[9] = 16 - 10;
902             buf[10] = 0x00;
903             buf[11] = 0x05;
904             buf[12] = 0x00;
905             buf[13] = 0x00;
906             buf[14] = 0x00;
907             buf[15] = 0x00;
908             ide_atapi_cmd_reply(s, 16, max_len);
909             break;
910         case MODE_PAGE_AUDIO_CTL:
911             cpu_to_ube16(&buf[0], 24 - 2);
912             buf[2] = 0x70;
913             buf[3] = 0;
914             buf[4] = 0;
915             buf[5] = 0;
916             buf[6] = 0;
917             buf[7] = 0;
918 
919             buf[8] = MODE_PAGE_AUDIO_CTL;
920             buf[9] = 24 - 10;
921             /* Fill with CDROM audio volume */
922             buf[17] = 0;
923             buf[19] = 0;
924             buf[21] = 0;
925             buf[23] = 0;
926 
927             ide_atapi_cmd_reply(s, 24, max_len);
928             break;
929         case MODE_PAGE_CAPABILITIES:
930             cpu_to_ube16(&buf[0], 30 - 2);
931             buf[2] = 0x70;
932             buf[3] = 0;
933             buf[4] = 0;
934             buf[5] = 0;
935             buf[6] = 0;
936             buf[7] = 0;
937 
938             buf[8] = MODE_PAGE_CAPABILITIES;
939             buf[9] = 30 - 10;
940             buf[10] = 0x3b; /* read CDR/CDRW/DVDROM/DVDR/DVDRAM */
941             buf[11] = 0x00;
942 
943             /* Claim PLAY_AUDIO capability (0x01) since some Linux
944                code checks for this to automount media. */
945             buf[12] = 0x71;
946             buf[13] = 3 << 5;
947             buf[14] = (1 << 0) | (1 << 3) | (1 << 5);
948             if (s->tray_locked) {
949                 buf[14] |= 1 << 1;
950             }
951             buf[15] = 0x00; /* No volume & mute control, no changer */
952             cpu_to_ube16(&buf[16], 704); /* 4x read speed */
953             buf[18] = 0; /* Two volume levels */
954             buf[19] = 2;
955             cpu_to_ube16(&buf[20], 512); /* 512k buffer */
956             cpu_to_ube16(&buf[22], 704); /* 4x read speed current */
957             buf[24] = 0;
958             buf[25] = 0;
959             buf[26] = 0;
960             buf[27] = 0;
961             buf[28] = 0;
962             buf[29] = 0;
963             ide_atapi_cmd_reply(s, 30, max_len);
964             break;
965         default:
966             goto error_cmd;
967         }
968         break;
969     case 1: /* changeable values */
970         goto error_cmd;
971     case 2: /* default values */
972         goto error_cmd;
973     default:
974     case 3: /* saved values */
975         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
976                             ASC_SAVING_PARAMETERS_NOT_SUPPORTED);
977         break;
978     }
979     return;
980 
981 error_cmd:
982     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_INV_FIELD_IN_CMD_PACKET);
983 }
984 
985 static void cmd_test_unit_ready(IDEState *s, uint8_t *buf)
986 {
987     /* Not Ready Conditions are already handled in ide_atapi_cmd(), so if we
988      * come here, we know that it's ready. */
989     ide_atapi_cmd_ok(s);
990 }
991 
992 static void cmd_prevent_allow_medium_removal(IDEState *s, uint8_t* buf)
993 {
994     s->tray_locked = buf[4] & 1;
995     blk_lock_medium(s->blk, buf[4] & 1);
996     ide_atapi_cmd_ok(s);
997 }
998 
999 static void cmd_read(IDEState *s, uint8_t* buf)
1000 {
1001     int nb_sectors, lba;
1002 
1003     if (buf[0] == GPCMD_READ_10) {
1004         nb_sectors = ube16_to_cpu(buf + 7);
1005     } else {
1006         nb_sectors = ube32_to_cpu(buf + 6);
1007     }
1008 
1009     lba = ube32_to_cpu(buf + 2);
1010     if (nb_sectors == 0) {
1011         ide_atapi_cmd_ok(s);
1012         return;
1013     }
1014 
1015     ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
1016 }
1017 
1018 static void cmd_read_cd(IDEState *s, uint8_t* buf)
1019 {
1020     int nb_sectors, lba, transfer_request;
1021 
1022     nb_sectors = (buf[6] << 16) | (buf[7] << 8) | buf[8];
1023     lba = ube32_to_cpu(buf + 2);
1024 
1025     if (nb_sectors == 0) {
1026         ide_atapi_cmd_ok(s);
1027         return;
1028     }
1029 
1030     transfer_request = buf[9];
1031     switch(transfer_request & 0xf8) {
1032     case 0x00:
1033         /* nothing */
1034         ide_atapi_cmd_ok(s);
1035         break;
1036     case 0x10:
1037         /* normal read */
1038         ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
1039         break;
1040     case 0xf8:
1041         /* read all data */
1042         ide_atapi_cmd_read(s, lba, nb_sectors, 2352);
1043         break;
1044     default:
1045         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1046                             ASC_INV_FIELD_IN_CMD_PACKET);
1047         break;
1048     }
1049 }
1050 
1051 static void cmd_seek(IDEState *s, uint8_t* buf)
1052 {
1053     unsigned int lba;
1054     uint64_t total_sectors = s->nb_sectors >> 2;
1055 
1056     lba = ube32_to_cpu(buf + 2);
1057     if (lba >= total_sectors) {
1058         ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_LOGICAL_BLOCK_OOR);
1059         return;
1060     }
1061 
1062     ide_atapi_cmd_ok(s);
1063 }
1064 
1065 static void cmd_start_stop_unit(IDEState *s, uint8_t* buf)
1066 {
1067     int sense;
1068     bool start = buf[4] & 1;
1069     bool loej = buf[4] & 2;     /* load on start, eject on !start */
1070     int pwrcnd = buf[4] & 0xf0;
1071 
1072     if (pwrcnd) {
1073         /* eject/load only happens for power condition == 0 */
1074         ide_atapi_cmd_ok(s);
1075         return;
1076     }
1077 
1078     if (loej) {
1079         if (!start && !s->tray_open && s->tray_locked) {
1080             sense = blk_is_inserted(s->blk)
1081                 ? NOT_READY : ILLEGAL_REQUEST;
1082             ide_atapi_cmd_error(s, sense, ASC_MEDIA_REMOVAL_PREVENTED);
1083             return;
1084         }
1085 
1086         if (s->tray_open != !start) {
1087             blk_eject(s->blk, !start);
1088             s->tray_open = !start;
1089         }
1090     }
1091 
1092     ide_atapi_cmd_ok(s);
1093 }
1094 
1095 static void cmd_mechanism_status(IDEState *s, uint8_t* buf)
1096 {
1097     int max_len = ube16_to_cpu(buf + 8);
1098 
1099     cpu_to_ube16(buf, 0);
1100     /* no current LBA */
1101     buf[2] = 0;
1102     buf[3] = 0;
1103     buf[4] = 0;
1104     buf[5] = 1;
1105     cpu_to_ube16(buf + 6, 0);
1106     ide_atapi_cmd_reply(s, 8, max_len);
1107 }
1108 
1109 static void cmd_read_toc_pma_atip(IDEState *s, uint8_t* buf)
1110 {
1111     int format, msf, start_track, len;
1112     int max_len;
1113     uint64_t total_sectors = s->nb_sectors >> 2;
1114 
1115     max_len = ube16_to_cpu(buf + 7);
1116     format = buf[9] >> 6;
1117     msf = (buf[1] >> 1) & 1;
1118     start_track = buf[6];
1119 
1120     switch(format) {
1121     case 0:
1122         len = cdrom_read_toc(total_sectors, buf, msf, start_track);
1123         if (len < 0)
1124             goto error_cmd;
1125         ide_atapi_cmd_reply(s, len, max_len);
1126         break;
1127     case 1:
1128         /* multi session : only a single session defined */
1129         memset(buf, 0, 12);
1130         buf[1] = 0x0a;
1131         buf[2] = 0x01;
1132         buf[3] = 0x01;
1133         ide_atapi_cmd_reply(s, 12, max_len);
1134         break;
1135     case 2:
1136         len = cdrom_read_toc_raw(total_sectors, buf, msf, start_track);
1137         if (len < 0)
1138             goto error_cmd;
1139         ide_atapi_cmd_reply(s, len, max_len);
1140         break;
1141     default:
1142     error_cmd:
1143         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1144                             ASC_INV_FIELD_IN_CMD_PACKET);
1145     }
1146 }
1147 
1148 static void cmd_read_cdvd_capacity(IDEState *s, uint8_t* buf)
1149 {
1150     uint64_t total_sectors = s->nb_sectors >> 2;
1151 
1152     /* NOTE: it is really the number of sectors minus 1 */
1153     cpu_to_ube32(buf, total_sectors - 1);
1154     cpu_to_ube32(buf + 4, 2048);
1155     ide_atapi_cmd_reply(s, 8, 8);
1156 }
1157 
1158 static void cmd_read_disc_information(IDEState *s, uint8_t* buf)
1159 {
1160     uint8_t type = buf[1] & 7;
1161     uint32_t max_len = ube16_to_cpu(buf + 7);
1162 
1163     /* Types 1/2 are only defined for Blu-Ray.  */
1164     if (type != 0) {
1165         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1166                             ASC_INV_FIELD_IN_CMD_PACKET);
1167         return;
1168     }
1169 
1170     memset(buf, 0, 34);
1171     buf[1] = 32;
1172     buf[2] = 0xe; /* last session complete, disc finalized */
1173     buf[3] = 1;   /* first track on disc */
1174     buf[4] = 1;   /* # of sessions */
1175     buf[5] = 1;   /* first track of last session */
1176     buf[6] = 1;   /* last track of last session */
1177     buf[7] = 0x20; /* unrestricted use */
1178     buf[8] = 0x00; /* CD-ROM or DVD-ROM */
1179     /* 9-10-11: most significant byte corresponding bytes 4-5-6 */
1180     /* 12-23: not meaningful for CD-ROM or DVD-ROM */
1181     /* 24-31: disc bar code */
1182     /* 32: disc application code */
1183     /* 33: number of OPC tables */
1184 
1185     ide_atapi_cmd_reply(s, 34, max_len);
1186 }
1187 
1188 static void cmd_read_dvd_structure(IDEState *s, uint8_t* buf)
1189 {
1190     int max_len;
1191     int media = buf[1];
1192     int format = buf[7];
1193     int ret;
1194 
1195     max_len = ube16_to_cpu(buf + 8);
1196 
1197     if (format < 0xff) {
1198         if (media_is_cd(s)) {
1199             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1200                                 ASC_INCOMPATIBLE_FORMAT);
1201             return;
1202         } else if (!media_present(s)) {
1203             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1204                                 ASC_INV_FIELD_IN_CMD_PACKET);
1205             return;
1206         }
1207     }
1208 
1209     memset(buf, 0, max_len > IDE_DMA_BUF_SECTORS * 512 + 4 ?
1210            IDE_DMA_BUF_SECTORS * 512 + 4 : max_len);
1211 
1212     switch (format) {
1213         case 0x00 ... 0x7f:
1214         case 0xff:
1215             if (media == 0) {
1216                 ret = ide_dvd_read_structure(s, format, buf, buf);
1217 
1218                 if (ret < 0) {
1219                     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, -ret);
1220                 } else {
1221                     ide_atapi_cmd_reply(s, ret, max_len);
1222                 }
1223 
1224                 break;
1225             }
1226             /* TODO: BD support, fall through for now */
1227 
1228         /* Generic disk structures */
1229         case 0x80: /* TODO: AACS volume identifier */
1230         case 0x81: /* TODO: AACS media serial number */
1231         case 0x82: /* TODO: AACS media identifier */
1232         case 0x83: /* TODO: AACS media key block */
1233         case 0x90: /* TODO: List of recognized format layers */
1234         case 0xc0: /* TODO: Write protection status */
1235         default:
1236             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1237                                 ASC_INV_FIELD_IN_CMD_PACKET);
1238             break;
1239     }
1240 }
1241 
1242 static void cmd_set_speed(IDEState *s, uint8_t* buf)
1243 {
1244     ide_atapi_cmd_ok(s);
1245 }
1246 
1247 enum {
1248     /*
1249      * Only commands flagged as ALLOW_UA are allowed to run under a
1250      * unit attention condition. (See MMC-5, section 4.1.6.1)
1251      */
1252     ALLOW_UA = 0x01,
1253 
1254     /*
1255      * Commands flagged with CHECK_READY can only execute if a medium is present.
1256      * Otherwise they report the Not Ready Condition. (See MMC-5, section
1257      * 4.1.8)
1258      */
1259     CHECK_READY = 0x02,
1260 
1261     /*
1262      * Commands flagged with NONDATA do not in any circumstances return
1263      * any data via ide_atapi_cmd_reply. These commands are exempt from
1264      * the normal byte_count_limit constraints.
1265      * See ATA8-ACS3 "7.21.5 Byte Count Limit"
1266      */
1267     NONDATA = 0x04,
1268 };
1269 
1270 static const struct AtapiCmd {
1271     void (*handler)(IDEState *s, uint8_t *buf);
1272     int flags;
1273 } atapi_cmd_table[0x100] = {
1274     [ 0x00 ] = { cmd_test_unit_ready,               CHECK_READY | NONDATA },
1275     [ 0x03 ] = { cmd_request_sense,                 ALLOW_UA },
1276     [ 0x12 ] = { cmd_inquiry,                       ALLOW_UA },
1277     [ 0x1b ] = { cmd_start_stop_unit,               NONDATA }, /* [1] */
1278     [ 0x1e ] = { cmd_prevent_allow_medium_removal,  NONDATA },
1279     [ 0x25 ] = { cmd_read_cdvd_capacity,            CHECK_READY },
1280     [ 0x28 ] = { cmd_read, /* (10) */               CHECK_READY },
1281     [ 0x2b ] = { cmd_seek,                          CHECK_READY | NONDATA },
1282     [ 0x43 ] = { cmd_read_toc_pma_atip,             CHECK_READY },
1283     [ 0x46 ] = { cmd_get_configuration,             ALLOW_UA },
1284     [ 0x4a ] = { cmd_get_event_status_notification, ALLOW_UA },
1285     [ 0x51 ] = { cmd_read_disc_information,         CHECK_READY },
1286     [ 0x5a ] = { cmd_mode_sense, /* (10) */         0 },
1287     [ 0xa8 ] = { cmd_read, /* (12) */               CHECK_READY },
1288     [ 0xad ] = { cmd_read_dvd_structure,            CHECK_READY },
1289     [ 0xbb ] = { cmd_set_speed,                     NONDATA },
1290     [ 0xbd ] = { cmd_mechanism_status,              0 },
1291     [ 0xbe ] = { cmd_read_cd,                       CHECK_READY },
1292     /* [1] handler detects and reports not ready condition itself */
1293 };
1294 
1295 void ide_atapi_cmd(IDEState *s)
1296 {
1297     uint8_t *buf = s->io_buffer;
1298     const struct AtapiCmd *cmd = &atapi_cmd_table[s->io_buffer[0]];
1299 
1300 #ifdef DEBUG_IDE_ATAPI
1301     {
1302         int i;
1303         printf("ATAPI limit=0x%x packet:", s->lcyl | (s->hcyl << 8));
1304         for(i = 0; i < ATAPI_PACKET_SIZE; i++) {
1305             printf(" %02x", buf[i]);
1306         }
1307         printf("\n");
1308     }
1309 #endif
1310 
1311     /*
1312      * If there's a UNIT_ATTENTION condition pending, only command flagged with
1313      * ALLOW_UA are allowed to complete. with other commands getting a CHECK
1314      * condition response unless a higher priority status, defined by the drive
1315      * here, is pending.
1316      */
1317     if (s->sense_key == UNIT_ATTENTION && !(cmd->flags & ALLOW_UA)) {
1318         ide_atapi_cmd_check_status(s);
1319         return;
1320     }
1321     /*
1322      * When a CD gets changed, we have to report an ejected state and
1323      * then a loaded state to guests so that they detect tray
1324      * open/close and media change events.  Guests that do not use
1325      * GET_EVENT_STATUS_NOTIFICATION to detect such tray open/close
1326      * states rely on this behavior.
1327      */
1328     if (!(cmd->flags & ALLOW_UA) &&
1329         !s->tray_open && blk_is_inserted(s->blk) && s->cdrom_changed) {
1330 
1331         if (s->cdrom_changed == 1) {
1332             ide_atapi_cmd_error(s, NOT_READY, ASC_MEDIUM_NOT_PRESENT);
1333             s->cdrom_changed = 2;
1334         } else {
1335             ide_atapi_cmd_error(s, UNIT_ATTENTION, ASC_MEDIUM_MAY_HAVE_CHANGED);
1336             s->cdrom_changed = 0;
1337         }
1338 
1339         return;
1340     }
1341 
1342     /* Report a Not Ready condition if appropriate for the command */
1343     if ((cmd->flags & CHECK_READY) &&
1344         (!media_present(s) || !blk_is_inserted(s->blk)))
1345     {
1346         ide_atapi_cmd_error(s, NOT_READY, ASC_MEDIUM_NOT_PRESENT);
1347         return;
1348     }
1349 
1350     /* Nondata commands permit the byte_count_limit to be 0.
1351      * If this is a data-transferring PIO command and BCL is 0,
1352      * we abort at the /ATA/ level, not the ATAPI level.
1353      * See ATA8 ACS3 section 7.17.6.49 and 7.21.5 */
1354     if (cmd->handler && !(cmd->flags & NONDATA)) {
1355         /* TODO: Check IDENTIFY data word 125 for default BCL (currently 0) */
1356         if (!(atapi_byte_count_limit(s) || s->atapi_dma)) {
1357             /* TODO: Move abort back into core.c and make static inline again */
1358             ide_abort_command(s);
1359             return;
1360         }
1361     }
1362 
1363     /* Execute the command */
1364     if (cmd->handler) {
1365         cmd->handler(s, buf);
1366         return;
1367     }
1368 
1369     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_ILLEGAL_OPCODE);
1370 }
1371