xref: /openbmc/qemu/hw/ide/atapi.c (revision c39f95dc)
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 #include "trace.h"
31 
32 #define ATAPI_SECTOR_BITS (2 + BDRV_SECTOR_BITS)
33 #define ATAPI_SECTOR_SIZE (1 << ATAPI_SECTOR_BITS)
34 
35 static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret);
36 
37 static void padstr8(uint8_t *buf, int buf_size, const char *src)
38 {
39     int i;
40     for(i = 0; i < buf_size; i++) {
41         if (*src)
42             buf[i] = *src++;
43         else
44             buf[i] = ' ';
45     }
46 }
47 
48 static inline void cpu_to_ube16(uint8_t *buf, int val)
49 {
50     buf[0] = val >> 8;
51     buf[1] = val & 0xff;
52 }
53 
54 static inline void cpu_to_ube32(uint8_t *buf, unsigned int val)
55 {
56     buf[0] = val >> 24;
57     buf[1] = val >> 16;
58     buf[2] = val >> 8;
59     buf[3] = val & 0xff;
60 }
61 
62 static inline int ube16_to_cpu(const uint8_t *buf)
63 {
64     return (buf[0] << 8) | buf[1];
65 }
66 
67 static inline int ube32_to_cpu(const uint8_t *buf)
68 {
69     return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
70 }
71 
72 static void lba_to_msf(uint8_t *buf, int lba)
73 {
74     lba += 150;
75     buf[0] = (lba / 75) / 60;
76     buf[1] = (lba / 75) % 60;
77     buf[2] = lba % 75;
78 }
79 
80 static inline int media_present(IDEState *s)
81 {
82     return !s->tray_open && s->nb_sectors > 0;
83 }
84 
85 /* XXX: DVDs that could fit on a CD will be reported as a CD */
86 static inline int media_is_dvd(IDEState *s)
87 {
88     return (media_present(s) && s->nb_sectors > CD_MAX_SECTORS);
89 }
90 
91 static inline int media_is_cd(IDEState *s)
92 {
93     return (media_present(s) && s->nb_sectors <= CD_MAX_SECTORS);
94 }
95 
96 static void cd_data_to_raw(uint8_t *buf, int lba)
97 {
98     /* sync bytes */
99     buf[0] = 0x00;
100     memset(buf + 1, 0xff, 10);
101     buf[11] = 0x00;
102     buf += 12;
103     /* MSF */
104     lba_to_msf(buf, lba);
105     buf[3] = 0x01; /* mode 1 data */
106     buf += 4;
107     /* data */
108     buf += 2048;
109     /* XXX: ECC not computed */
110     memset(buf, 0, 288);
111 }
112 
113 static int
114 cd_read_sector_sync(IDEState *s)
115 {
116     int ret;
117     block_acct_start(blk_get_stats(s->blk), &s->acct,
118                      ATAPI_SECTOR_SIZE, BLOCK_ACCT_READ);
119 
120     trace_cd_read_sector_sync(s->lba);
121 
122     switch (s->cd_sector_size) {
123     case 2048:
124         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
125                         s->io_buffer, ATAPI_SECTOR_SIZE);
126         break;
127     case 2352:
128         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
129                         s->io_buffer + 16, ATAPI_SECTOR_SIZE);
130         if (ret >= 0) {
131             cd_data_to_raw(s->io_buffer, s->lba);
132         }
133         break;
134     default:
135         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_READ);
136         return -EIO;
137     }
138 
139     if (ret < 0) {
140         block_acct_failed(blk_get_stats(s->blk), &s->acct);
141     } else {
142         block_acct_done(blk_get_stats(s->blk), &s->acct);
143         s->lba++;
144         s->io_buffer_index = 0;
145     }
146 
147     return ret;
148 }
149 
150 static void cd_read_sector_cb(void *opaque, int ret)
151 {
152     IDEState *s = opaque;
153 
154     trace_cd_read_sector_cb(s->lba, ret);
155 
156     if (ret < 0) {
157         block_acct_failed(blk_get_stats(s->blk), &s->acct);
158         ide_atapi_io_error(s, ret);
159         return;
160     }
161 
162     block_acct_done(blk_get_stats(s->blk), &s->acct);
163 
164     if (s->cd_sector_size == 2352) {
165         cd_data_to_raw(s->io_buffer, s->lba);
166     }
167 
168     s->lba++;
169     s->io_buffer_index = 0;
170     s->status &= ~BUSY_STAT;
171 
172     ide_atapi_cmd_reply_end(s);
173 }
174 
175 static int cd_read_sector(IDEState *s)
176 {
177     if (s->cd_sector_size != 2048 && s->cd_sector_size != 2352) {
178         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_READ);
179         return -EINVAL;
180     }
181 
182     s->iov.iov_base = (s->cd_sector_size == 2352) ?
183                       s->io_buffer + 16 : s->io_buffer;
184 
185     s->iov.iov_len = ATAPI_SECTOR_SIZE;
186     qemu_iovec_init_external(&s->qiov, &s->iov, 1);
187 
188     trace_cd_read_sector(s->lba);
189 
190     block_acct_start(blk_get_stats(s->blk), &s->acct,
191                      ATAPI_SECTOR_SIZE, BLOCK_ACCT_READ);
192 
193     ide_buffered_readv(s, (int64_t)s->lba << 2, &s->qiov, 4,
194                        cd_read_sector_cb, s);
195 
196     s->status |= BUSY_STAT;
197     return 0;
198 }
199 
200 void ide_atapi_cmd_ok(IDEState *s)
201 {
202     s->error = 0;
203     s->status = READY_STAT | SEEK_STAT;
204     s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
205     ide_transfer_stop(s);
206     ide_set_irq(s->bus);
207 }
208 
209 void ide_atapi_cmd_error(IDEState *s, int sense_key, int asc)
210 {
211     trace_ide_atapi_cmd_error(s, sense_key, asc);
212     s->error = sense_key << 4;
213     s->status = READY_STAT | ERR_STAT;
214     s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
215     s->sense_key = sense_key;
216     s->asc = asc;
217     ide_transfer_stop(s);
218     ide_set_irq(s->bus);
219 }
220 
221 void ide_atapi_io_error(IDEState *s, int ret)
222 {
223     /* XXX: handle more errors */
224     if (ret == -ENOMEDIUM) {
225         ide_atapi_cmd_error(s, NOT_READY,
226                             ASC_MEDIUM_NOT_PRESENT);
227     } else {
228         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
229                             ASC_LOGICAL_BLOCK_OOR);
230     }
231 }
232 
233 static uint16_t atapi_byte_count_limit(IDEState *s)
234 {
235     uint16_t bcl;
236 
237     bcl = s->lcyl | (s->hcyl << 8);
238     if (bcl == 0xffff) {
239         return 0xfffe;
240     }
241     return bcl;
242 }
243 
244 /* The whole ATAPI transfer logic is handled in this function */
245 void ide_atapi_cmd_reply_end(IDEState *s)
246 {
247     int byte_count_limit, size, ret;
248     trace_ide_atapi_cmd_reply_end(s, s->packet_transfer_size,
249                                   s->elementary_transfer_size,
250                                   s->io_buffer_index);
251     if (s->packet_transfer_size <= 0) {
252         /* end of transfer */
253         ide_atapi_cmd_ok(s);
254         ide_set_irq(s->bus);
255         trace_ide_atapi_cmd_reply_end_eot(s, s->status);
256     } else {
257         /* see if a new sector must be read */
258         if (s->lba != -1 && s->io_buffer_index >= s->cd_sector_size) {
259             if (!s->elementary_transfer_size) {
260                 ret = cd_read_sector(s);
261                 if (ret < 0) {
262                     ide_atapi_io_error(s, ret);
263                 }
264                 return;
265             } else {
266                 /* rebuffering within an elementary transfer is
267                  * only possible with a sync request because we
268                  * end up with a race condition otherwise */
269                 ret = cd_read_sector_sync(s);
270                 if (ret < 0) {
271                     ide_atapi_io_error(s, ret);
272                     return;
273                 }
274             }
275         }
276         if (s->elementary_transfer_size > 0) {
277             /* there are some data left to transmit in this elementary
278                transfer */
279             size = s->cd_sector_size - s->io_buffer_index;
280             if (size > s->elementary_transfer_size)
281                 size = s->elementary_transfer_size;
282             s->packet_transfer_size -= size;
283             s->elementary_transfer_size -= size;
284             s->io_buffer_index += size;
285             ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
286                                size, ide_atapi_cmd_reply_end);
287         } else {
288             /* a new transfer is needed */
289             s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
290             byte_count_limit = atapi_byte_count_limit(s);
291             trace_ide_atapi_cmd_reply_end_bcl(s, byte_count_limit);
292             size = s->packet_transfer_size;
293             if (size > byte_count_limit) {
294                 /* byte count limit must be even if this case */
295                 if (byte_count_limit & 1)
296                     byte_count_limit--;
297                 size = byte_count_limit;
298             }
299             s->lcyl = size;
300             s->hcyl = size >> 8;
301             s->elementary_transfer_size = size;
302             /* we cannot transmit more than one sector at a time */
303             if (s->lba != -1) {
304                 if (size > (s->cd_sector_size - s->io_buffer_index))
305                     size = (s->cd_sector_size - s->io_buffer_index);
306             }
307             s->packet_transfer_size -= size;
308             s->elementary_transfer_size -= size;
309             s->io_buffer_index += size;
310             ide_transfer_start(s, s->io_buffer + s->io_buffer_index - size,
311                                size, ide_atapi_cmd_reply_end);
312             ide_set_irq(s->bus);
313             trace_ide_atapi_cmd_reply_end_new(s, s->status);
314         }
315     }
316 }
317 
318 /* send a reply of 'size' bytes in s->io_buffer to an ATAPI command */
319 static void ide_atapi_cmd_reply(IDEState *s, int size, int max_size)
320 {
321     if (size > max_size)
322         size = max_size;
323     s->lba = -1; /* no sector read */
324     s->packet_transfer_size = size;
325     s->io_buffer_size = size;    /* dma: send the reply data as one chunk */
326     s->elementary_transfer_size = 0;
327 
328     if (s->atapi_dma) {
329         block_acct_start(blk_get_stats(s->blk), &s->acct, size,
330                          BLOCK_ACCT_READ);
331         s->status = READY_STAT | SEEK_STAT | DRQ_STAT;
332         ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
333     } else {
334         s->status = READY_STAT | SEEK_STAT;
335         s->io_buffer_index = 0;
336         ide_atapi_cmd_reply_end(s);
337     }
338 }
339 
340 /* start a CD-CDROM read command */
341 static void ide_atapi_cmd_read_pio(IDEState *s, int lba, int nb_sectors,
342                                    int sector_size)
343 {
344     s->lba = lba;
345     s->packet_transfer_size = nb_sectors * sector_size;
346     s->elementary_transfer_size = 0;
347     s->io_buffer_index = sector_size;
348     s->cd_sector_size = sector_size;
349 
350     ide_atapi_cmd_reply_end(s);
351 }
352 
353 static void ide_atapi_cmd_check_status(IDEState *s)
354 {
355     trace_ide_atapi_cmd_check_status(s);
356     s->error = MC_ERR | (UNIT_ATTENTION << 4);
357     s->status = ERR_STAT;
358     s->nsector = 0;
359     ide_set_irq(s->bus);
360 }
361 /* ATAPI DMA support */
362 
363 static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret)
364 {
365     IDEState *s = opaque;
366     int data_offset, n;
367 
368     if (ret < 0) {
369         if (ide_handle_rw_error(s, -ret, ide_dma_cmd_to_retry(s->dma_cmd))) {
370             if (s->bus->error_status) {
371                 s->bus->dma->aiocb = NULL;
372                 return;
373             }
374             goto eot;
375         }
376     }
377 
378     if (s->io_buffer_size > 0) {
379         /*
380          * For a cdrom read sector command (s->lba != -1),
381          * adjust the lba for the next s->io_buffer_size chunk
382          * and dma the current chunk.
383          * For a command != read (s->lba == -1), just transfer
384          * the reply data.
385          */
386         if (s->lba != -1) {
387             if (s->cd_sector_size == 2352) {
388                 n = 1;
389                 cd_data_to_raw(s->io_buffer, s->lba);
390             } else {
391                 n = s->io_buffer_size >> 11;
392             }
393             s->lba += n;
394         }
395         s->packet_transfer_size -= s->io_buffer_size;
396         if (s->bus->dma->ops->rw_buf(s->bus->dma, 1) == 0)
397             goto eot;
398     }
399 
400     if (s->packet_transfer_size <= 0) {
401         s->status = READY_STAT | SEEK_STAT;
402         s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
403         ide_set_irq(s->bus);
404         goto eot;
405     }
406 
407     s->io_buffer_index = 0;
408     if (s->cd_sector_size == 2352) {
409         n = 1;
410         s->io_buffer_size = s->cd_sector_size;
411         data_offset = 16;
412     } else {
413         n = s->packet_transfer_size >> 11;
414         if (n > (IDE_DMA_BUF_SECTORS / 4))
415             n = (IDE_DMA_BUF_SECTORS / 4);
416         s->io_buffer_size = n * 2048;
417         data_offset = 0;
418     }
419     trace_ide_atapi_cmd_read_dma_cb_aio(s, s->lba, n);
420     s->bus->dma->iov.iov_base = (void *)(s->io_buffer + data_offset);
421     s->bus->dma->iov.iov_len = n * ATAPI_SECTOR_SIZE;
422     qemu_iovec_init_external(&s->bus->dma->qiov, &s->bus->dma->iov, 1);
423 
424     s->bus->dma->aiocb = ide_buffered_readv(s, (int64_t)s->lba << 2,
425                                             &s->bus->dma->qiov, n * 4,
426                                             ide_atapi_cmd_read_dma_cb, s);
427     return;
428 
429 eot:
430     if (ret < 0) {
431         block_acct_failed(blk_get_stats(s->blk), &s->acct);
432     } else {
433         block_acct_done(blk_get_stats(s->blk), &s->acct);
434     }
435     ide_set_inactive(s, false);
436 }
437 
438 /* start a CD-CDROM read command with DMA */
439 /* XXX: test if DMA is available */
440 static void ide_atapi_cmd_read_dma(IDEState *s, int lba, int nb_sectors,
441                                    int sector_size)
442 {
443     s->lba = lba;
444     s->packet_transfer_size = nb_sectors * sector_size;
445     s->io_buffer_size = 0;
446     s->cd_sector_size = sector_size;
447 
448     block_acct_start(blk_get_stats(s->blk), &s->acct, s->packet_transfer_size,
449                      BLOCK_ACCT_READ);
450 
451     /* XXX: check if BUSY_STAT should be set */
452     s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
453     ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
454 }
455 
456 static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors,
457                                int sector_size)
458 {
459     trace_ide_atapi_cmd_read(s, s->atapi_dma ? "dma" : "pio",
460                              lba, nb_sectors);
461     if (s->atapi_dma) {
462         ide_atapi_cmd_read_dma(s, lba, nb_sectors, sector_size);
463     } else {
464         ide_atapi_cmd_read_pio(s, lba, nb_sectors, sector_size);
465     }
466 }
467 
468 void ide_atapi_dma_restart(IDEState *s)
469 {
470     /*
471      * At this point we can just re-evaluate the packet command and start over.
472      * The presence of ->dma_cb callback in the pre_save ensures that the packet
473      * command has been completely sent and we can safely restart command.
474      */
475     s->unit = s->bus->retry_unit;
476     s->bus->dma->ops->restart_dma(s->bus->dma);
477     ide_atapi_cmd(s);
478 }
479 
480 static inline uint8_t ide_atapi_set_profile(uint8_t *buf, uint8_t *index,
481                                             uint16_t profile)
482 {
483     uint8_t *buf_profile = buf + 12; /* start of profiles */
484 
485     buf_profile += ((*index) * 4); /* start of indexed profile */
486     cpu_to_ube16 (buf_profile, profile);
487     buf_profile[2] = ((buf_profile[0] == buf[6]) && (buf_profile[1] == buf[7]));
488 
489     /* each profile adds 4 bytes to the response */
490     (*index)++;
491     buf[11] += 4; /* Additional Length */
492 
493     return 4;
494 }
495 
496 static int ide_dvd_read_structure(IDEState *s, int format,
497                                   const uint8_t *packet, uint8_t *buf)
498 {
499     switch (format) {
500         case 0x0: /* Physical format information */
501             {
502                 int layer = packet[6];
503                 uint64_t total_sectors;
504 
505                 if (layer != 0)
506                     return -ASC_INV_FIELD_IN_CMD_PACKET;
507 
508                 total_sectors = s->nb_sectors >> 2;
509                 if (total_sectors == 0) {
510                     return -ASC_MEDIUM_NOT_PRESENT;
511                 }
512 
513                 buf[4] = 1;   /* DVD-ROM, part version 1 */
514                 buf[5] = 0xf; /* 120mm disc, minimum rate unspecified */
515                 buf[6] = 1;   /* one layer, read-only (per MMC-2 spec) */
516                 buf[7] = 0;   /* default densities */
517 
518                 /* FIXME: 0x30000 per spec? */
519                 cpu_to_ube32(buf + 8, 0); /* start sector */
520                 cpu_to_ube32(buf + 12, total_sectors - 1); /* end sector */
521                 cpu_to_ube32(buf + 16, total_sectors - 1); /* l0 end sector */
522 
523                 /* Size of buffer, not including 2 byte size field */
524                 stw_be_p(buf, 2048 + 2);
525 
526                 /* 2k data + 4 byte header */
527                 return (2048 + 4);
528             }
529 
530         case 0x01: /* DVD copyright information */
531             buf[4] = 0; /* no copyright data */
532             buf[5] = 0; /* no region restrictions */
533 
534             /* Size of buffer, not including 2 byte size field */
535             stw_be_p(buf, 4 + 2);
536 
537             /* 4 byte header + 4 byte data */
538             return (4 + 4);
539 
540         case 0x03: /* BCA information - invalid field for no BCA info */
541             return -ASC_INV_FIELD_IN_CMD_PACKET;
542 
543         case 0x04: /* DVD disc manufacturing information */
544             /* Size of buffer, not including 2 byte size field */
545             stw_be_p(buf, 2048 + 2);
546 
547             /* 2k data + 4 byte header */
548             return (2048 + 4);
549 
550         case 0xff:
551             /*
552              * This lists all the command capabilities above.  Add new ones
553              * in order and update the length and buffer return values.
554              */
555 
556             buf[4] = 0x00; /* Physical format */
557             buf[5] = 0x40; /* Not writable, is readable */
558             stw_be_p(buf + 6, 2048 + 4);
559 
560             buf[8] = 0x01; /* Copyright info */
561             buf[9] = 0x40; /* Not writable, is readable */
562             stw_be_p(buf + 10, 4 + 4);
563 
564             buf[12] = 0x03; /* BCA info */
565             buf[13] = 0x40; /* Not writable, is readable */
566             stw_be_p(buf + 14, 188 + 4);
567 
568             buf[16] = 0x04; /* Manufacturing info */
569             buf[17] = 0x40; /* Not writable, is readable */
570             stw_be_p(buf + 18, 2048 + 4);
571 
572             /* Size of buffer, not including 2 byte size field */
573             stw_be_p(buf, 16 + 2);
574 
575             /* data written + 4 byte header */
576             return (16 + 4);
577 
578         default: /* TODO: formats beyond DVD-ROM requires */
579             return -ASC_INV_FIELD_IN_CMD_PACKET;
580     }
581 }
582 
583 static unsigned int event_status_media(IDEState *s,
584                                        uint8_t *buf)
585 {
586     uint8_t event_code, media_status;
587 
588     media_status = 0;
589     if (s->tray_open) {
590         media_status = MS_TRAY_OPEN;
591     } else if (blk_is_inserted(s->blk)) {
592         media_status = MS_MEDIA_PRESENT;
593     }
594 
595     /* Event notification descriptor */
596     event_code = MEC_NO_CHANGE;
597     if (media_status != MS_TRAY_OPEN) {
598         if (s->events.new_media) {
599             event_code = MEC_NEW_MEDIA;
600             s->events.new_media = false;
601         } else if (s->events.eject_request) {
602             event_code = MEC_EJECT_REQUESTED;
603             s->events.eject_request = false;
604         }
605     }
606 
607     buf[4] = event_code;
608     buf[5] = media_status;
609 
610     /* These fields are reserved, just clear them. */
611     buf[6] = 0;
612     buf[7] = 0;
613 
614     return 8; /* We wrote to 4 extra bytes from the header */
615 }
616 
617 /*
618  * Before transferring data or otherwise signalling acceptance of a command
619  * marked CONDDATA, we must check the validity of the byte_count_limit.
620  */
621 static bool validate_bcl(IDEState *s)
622 {
623     /* TODO: Check IDENTIFY data word 125 for defacult BCL (currently 0) */
624     if (s->atapi_dma || atapi_byte_count_limit(s)) {
625         return true;
626     }
627 
628     /* TODO: Move abort back into core.c and introduce proper error flow between
629      *       ATAPI layer and IDE core layer */
630     ide_abort_command(s);
631     return false;
632 }
633 
634 static void cmd_get_event_status_notification(IDEState *s,
635                                               uint8_t *buf)
636 {
637     const uint8_t *packet = buf;
638 
639     struct {
640         uint8_t opcode;
641         uint8_t polled;        /* lsb bit is polled; others are reserved */
642         uint8_t reserved2[2];
643         uint8_t class;
644         uint8_t reserved3[2];
645         uint16_t len;
646         uint8_t control;
647     } QEMU_PACKED *gesn_cdb;
648 
649     struct {
650         uint16_t len;
651         uint8_t notification_class;
652         uint8_t supported_events;
653     } QEMU_PACKED *gesn_event_header;
654     unsigned int max_len, used_len;
655 
656     gesn_cdb = (void *)packet;
657     gesn_event_header = (void *)buf;
658 
659     max_len = be16_to_cpu(gesn_cdb->len);
660 
661     /* It is fine by the MMC spec to not support async mode operations */
662     if (!(gesn_cdb->polled & 0x01)) { /* asynchronous mode */
663         /* Only polling is supported, asynchronous mode is not. */
664         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
665                             ASC_INV_FIELD_IN_CMD_PACKET);
666         return;
667     }
668 
669     /* polling mode operation */
670 
671     /*
672      * These are the supported events.
673      *
674      * We currently only support requests of the 'media' type.
675      * Notification class requests and supported event classes are bitmasks,
676      * but they are build from the same values as the "notification class"
677      * field.
678      */
679     gesn_event_header->supported_events = 1 << GESN_MEDIA;
680 
681     /*
682      * We use |= below to set the class field; other bits in this byte
683      * are reserved now but this is useful to do if we have to use the
684      * reserved fields later.
685      */
686     gesn_event_header->notification_class = 0;
687 
688     /*
689      * Responses to requests are to be based on request priority.  The
690      * notification_class_request_type enum above specifies the
691      * priority: upper elements are higher prio than lower ones.
692      */
693     if (gesn_cdb->class & (1 << GESN_MEDIA)) {
694         gesn_event_header->notification_class |= GESN_MEDIA;
695         used_len = event_status_media(s, buf);
696     } else {
697         gesn_event_header->notification_class = 0x80; /* No event available */
698         used_len = sizeof(*gesn_event_header);
699     }
700     gesn_event_header->len = cpu_to_be16(used_len
701                                          - sizeof(*gesn_event_header));
702     ide_atapi_cmd_reply(s, used_len, max_len);
703 }
704 
705 static void cmd_request_sense(IDEState *s, uint8_t *buf)
706 {
707     int max_len = buf[4];
708 
709     memset(buf, 0, 18);
710     buf[0] = 0x70 | (1 << 7);
711     buf[2] = s->sense_key;
712     buf[7] = 10;
713     buf[12] = s->asc;
714 
715     if (s->sense_key == UNIT_ATTENTION) {
716         s->sense_key = NO_SENSE;
717     }
718 
719     ide_atapi_cmd_reply(s, 18, max_len);
720 }
721 
722 static void cmd_inquiry(IDEState *s, uint8_t *buf)
723 {
724     uint8_t page_code = buf[2];
725     int max_len = buf[4];
726 
727     unsigned idx = 0;
728     unsigned size_idx;
729     unsigned preamble_len;
730 
731     /* If the EVPD (Enable Vital Product Data) bit is set in byte 1,
732      * we are being asked for a specific page of info indicated by byte 2. */
733     if (buf[1] & 0x01) {
734         preamble_len = 4;
735         size_idx = 3;
736 
737         buf[idx++] = 0x05;      /* CD-ROM */
738         buf[idx++] = page_code; /* Page Code */
739         buf[idx++] = 0x00;      /* reserved */
740         idx++;                  /* length (set later) */
741 
742         switch (page_code) {
743         case 0x00:
744             /* Supported Pages: List of supported VPD responses. */
745             buf[idx++] = 0x00; /* 0x00: Supported Pages, and: */
746             buf[idx++] = 0x83; /* 0x83: Device Identification. */
747             break;
748 
749         case 0x83:
750             /* Device Identification. Each entry is optional, but the entries
751              * included here are modeled after libata's VPD responses.
752              * If the response is given, at least one entry must be present. */
753 
754             /* Entry 1: Serial */
755             if (idx + 24 > max_len) {
756                 /* Not enough room for even the first entry: */
757                 /* 4 byte header + 20 byte string */
758                 ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
759                                     ASC_DATA_PHASE_ERROR);
760                 return;
761             }
762             buf[idx++] = 0x02; /* Ascii */
763             buf[idx++] = 0x00; /* Vendor Specific */
764             buf[idx++] = 0x00;
765             buf[idx++] = 20;   /* Remaining length */
766             padstr8(buf + idx, 20, s->drive_serial_str);
767             idx += 20;
768 
769             /* Entry 2: Drive Model and Serial */
770             if (idx + 72 > max_len) {
771                 /* 4 (header) + 8 (vendor) + 60 (model & serial) */
772                 goto out;
773             }
774             buf[idx++] = 0x02; /* Ascii */
775             buf[idx++] = 0x01; /* T10 Vendor */
776             buf[idx++] = 0x00;
777             buf[idx++] = 68;
778             padstr8(buf + idx, 8, "ATA"); /* Generic T10 vendor */
779             idx += 8;
780             padstr8(buf + idx, 40, s->drive_model_str);
781             idx += 40;
782             padstr8(buf + idx, 20, s->drive_serial_str);
783             idx += 20;
784 
785             /* Entry 3: WWN */
786             if (s->wwn && (idx + 12 <= max_len)) {
787                 /* 4 byte header + 8 byte wwn */
788                 buf[idx++] = 0x01; /* Binary */
789                 buf[idx++] = 0x03; /* NAA */
790                 buf[idx++] = 0x00;
791                 buf[idx++] = 0x08;
792                 stq_be_p(&buf[idx], s->wwn);
793                 idx += 8;
794             }
795             break;
796 
797         default:
798             /* SPC-3, revision 23 sec. 6.4 */
799             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
800                                 ASC_INV_FIELD_IN_CMD_PACKET);
801             return;
802         }
803     } else {
804         preamble_len = 5;
805         size_idx = 4;
806 
807         buf[0] = 0x05; /* CD-ROM */
808         buf[1] = 0x80; /* removable */
809         buf[2] = 0x00; /* ISO */
810         buf[3] = 0x21; /* ATAPI-2 (XXX: put ATAPI-4 ?) */
811         /* buf[size_idx] set below. */
812         buf[5] = 0;    /* reserved */
813         buf[6] = 0;    /* reserved */
814         buf[7] = 0;    /* reserved */
815         padstr8(buf + 8, 8, "QEMU");
816         padstr8(buf + 16, 16, "QEMU DVD-ROM");
817         padstr8(buf + 32, 4, s->version);
818         idx = 36;
819     }
820 
821  out:
822     buf[size_idx] = idx - preamble_len;
823     ide_atapi_cmd_reply(s, idx, max_len);
824 }
825 
826 static void cmd_get_configuration(IDEState *s, uint8_t *buf)
827 {
828     uint32_t len;
829     uint8_t index = 0;
830     int max_len;
831 
832     /* only feature 0 is supported */
833     if (buf[2] != 0 || buf[3] != 0) {
834         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
835                             ASC_INV_FIELD_IN_CMD_PACKET);
836         return;
837     }
838 
839     /* XXX: could result in alignment problems in some architectures */
840     max_len = ube16_to_cpu(buf + 7);
841 
842     /*
843      * XXX: avoid overflow for io_buffer if max_len is bigger than
844      *      the size of that buffer (dimensioned to max number of
845      *      sectors to transfer at once)
846      *
847      *      Only a problem if the feature/profiles grow.
848      */
849     if (max_len > 512) {
850         /* XXX: assume 1 sector */
851         max_len = 512;
852     }
853 
854     memset(buf, 0, max_len);
855     /*
856      * the number of sectors from the media tells us which profile
857      * to use as current.  0 means there is no media
858      */
859     if (media_is_dvd(s)) {
860         cpu_to_ube16(buf + 6, MMC_PROFILE_DVD_ROM);
861     } else if (media_is_cd(s)) {
862         cpu_to_ube16(buf + 6, MMC_PROFILE_CD_ROM);
863     }
864 
865     buf[10] = 0x02 | 0x01; /* persistent and current */
866     len = 12; /* headers: 8 + 4 */
867     len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_DVD_ROM);
868     len += ide_atapi_set_profile(buf, &index, MMC_PROFILE_CD_ROM);
869     cpu_to_ube32(buf, len - 4); /* data length */
870 
871     ide_atapi_cmd_reply(s, len, max_len);
872 }
873 
874 static void cmd_mode_sense(IDEState *s, uint8_t *buf)
875 {
876     int action, code;
877     int max_len;
878 
879     max_len = ube16_to_cpu(buf + 7);
880     action = buf[2] >> 6;
881     code = buf[2] & 0x3f;
882 
883     switch(action) {
884     case 0: /* current values */
885         switch(code) {
886         case MODE_PAGE_R_W_ERROR: /* error recovery */
887             cpu_to_ube16(&buf[0], 16 - 2);
888             buf[2] = 0x70;
889             buf[3] = 0;
890             buf[4] = 0;
891             buf[5] = 0;
892             buf[6] = 0;
893             buf[7] = 0;
894 
895             buf[8] = MODE_PAGE_R_W_ERROR;
896             buf[9] = 16 - 10;
897             buf[10] = 0x00;
898             buf[11] = 0x05;
899             buf[12] = 0x00;
900             buf[13] = 0x00;
901             buf[14] = 0x00;
902             buf[15] = 0x00;
903             ide_atapi_cmd_reply(s, 16, max_len);
904             break;
905         case MODE_PAGE_AUDIO_CTL:
906             cpu_to_ube16(&buf[0], 24 - 2);
907             buf[2] = 0x70;
908             buf[3] = 0;
909             buf[4] = 0;
910             buf[5] = 0;
911             buf[6] = 0;
912             buf[7] = 0;
913 
914             buf[8] = MODE_PAGE_AUDIO_CTL;
915             buf[9] = 24 - 10;
916             /* Fill with CDROM audio volume */
917             buf[17] = 0;
918             buf[19] = 0;
919             buf[21] = 0;
920             buf[23] = 0;
921 
922             ide_atapi_cmd_reply(s, 24, max_len);
923             break;
924         case MODE_PAGE_CAPABILITIES:
925             cpu_to_ube16(&buf[0], 30 - 2);
926             buf[2] = 0x70;
927             buf[3] = 0;
928             buf[4] = 0;
929             buf[5] = 0;
930             buf[6] = 0;
931             buf[7] = 0;
932 
933             buf[8] = MODE_PAGE_CAPABILITIES;
934             buf[9] = 30 - 10;
935             buf[10] = 0x3b; /* read CDR/CDRW/DVDROM/DVDR/DVDRAM */
936             buf[11] = 0x00;
937 
938             /* Claim PLAY_AUDIO capability (0x01) since some Linux
939                code checks for this to automount media. */
940             buf[12] = 0x71;
941             buf[13] = 3 << 5;
942             buf[14] = (1 << 0) | (1 << 3) | (1 << 5);
943             if (s->tray_locked) {
944                 buf[14] |= 1 << 1;
945             }
946             buf[15] = 0x00; /* No volume & mute control, no changer */
947             cpu_to_ube16(&buf[16], 704); /* 4x read speed */
948             buf[18] = 0; /* Two volume levels */
949             buf[19] = 2;
950             cpu_to_ube16(&buf[20], 512); /* 512k buffer */
951             cpu_to_ube16(&buf[22], 704); /* 4x read speed current */
952             buf[24] = 0;
953             buf[25] = 0;
954             buf[26] = 0;
955             buf[27] = 0;
956             buf[28] = 0;
957             buf[29] = 0;
958             ide_atapi_cmd_reply(s, 30, max_len);
959             break;
960         default:
961             goto error_cmd;
962         }
963         break;
964     case 1: /* changeable values */
965         goto error_cmd;
966     case 2: /* default values */
967         goto error_cmd;
968     default:
969     case 3: /* saved values */
970         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
971                             ASC_SAVING_PARAMETERS_NOT_SUPPORTED);
972         break;
973     }
974     return;
975 
976 error_cmd:
977     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_INV_FIELD_IN_CMD_PACKET);
978 }
979 
980 static void cmd_test_unit_ready(IDEState *s, uint8_t *buf)
981 {
982     /* Not Ready Conditions are already handled in ide_atapi_cmd(), so if we
983      * come here, we know that it's ready. */
984     ide_atapi_cmd_ok(s);
985 }
986 
987 static void cmd_prevent_allow_medium_removal(IDEState *s, uint8_t* buf)
988 {
989     s->tray_locked = buf[4] & 1;
990     blk_lock_medium(s->blk, buf[4] & 1);
991     ide_atapi_cmd_ok(s);
992 }
993 
994 static void cmd_read(IDEState *s, uint8_t* buf)
995 {
996     int nb_sectors, lba;
997 
998     if (buf[0] == GPCMD_READ_10) {
999         nb_sectors = ube16_to_cpu(buf + 7);
1000     } else {
1001         nb_sectors = ube32_to_cpu(buf + 6);
1002     }
1003 
1004     lba = ube32_to_cpu(buf + 2);
1005     if (nb_sectors == 0) {
1006         ide_atapi_cmd_ok(s);
1007         return;
1008     }
1009 
1010     ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
1011 }
1012 
1013 static void cmd_read_cd(IDEState *s, uint8_t* buf)
1014 {
1015     int nb_sectors, lba, transfer_request;
1016 
1017     nb_sectors = (buf[6] << 16) | (buf[7] << 8) | buf[8];
1018     lba = ube32_to_cpu(buf + 2);
1019 
1020     if (nb_sectors == 0) {
1021         ide_atapi_cmd_ok(s);
1022         return;
1023     }
1024 
1025     transfer_request = buf[9] & 0xf8;
1026     if (transfer_request == 0x00) {
1027         /* nothing */
1028         ide_atapi_cmd_ok(s);
1029         return;
1030     }
1031 
1032     /* Check validity of BCL before transferring data */
1033     if (!validate_bcl(s)) {
1034         return;
1035     }
1036 
1037     switch (transfer_request) {
1038     case 0x10:
1039         /* normal read */
1040         ide_atapi_cmd_read(s, lba, nb_sectors, 2048);
1041         break;
1042     case 0xf8:
1043         /* read all data */
1044         ide_atapi_cmd_read(s, lba, nb_sectors, 2352);
1045         break;
1046     default:
1047         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1048                             ASC_INV_FIELD_IN_CMD_PACKET);
1049         break;
1050     }
1051 }
1052 
1053 static void cmd_seek(IDEState *s, uint8_t* buf)
1054 {
1055     unsigned int lba;
1056     uint64_t total_sectors = s->nb_sectors >> 2;
1057 
1058     lba = ube32_to_cpu(buf + 2);
1059     if (lba >= total_sectors) {
1060         ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_LOGICAL_BLOCK_OOR);
1061         return;
1062     }
1063 
1064     ide_atapi_cmd_ok(s);
1065 }
1066 
1067 static void cmd_start_stop_unit(IDEState *s, uint8_t* buf)
1068 {
1069     int sense;
1070     bool start = buf[4] & 1;
1071     bool loej = buf[4] & 2;     /* load on start, eject on !start */
1072     int pwrcnd = buf[4] & 0xf0;
1073 
1074     if (pwrcnd) {
1075         /* eject/load only happens for power condition == 0 */
1076         ide_atapi_cmd_ok(s);
1077         return;
1078     }
1079 
1080     if (loej) {
1081         if (!start && !s->tray_open && s->tray_locked) {
1082             sense = blk_is_inserted(s->blk)
1083                 ? NOT_READY : ILLEGAL_REQUEST;
1084             ide_atapi_cmd_error(s, sense, ASC_MEDIA_REMOVAL_PREVENTED);
1085             return;
1086         }
1087 
1088         if (s->tray_open != !start) {
1089             blk_eject(s->blk, !start);
1090             s->tray_open = !start;
1091         }
1092     }
1093 
1094     ide_atapi_cmd_ok(s);
1095 }
1096 
1097 static void cmd_mechanism_status(IDEState *s, uint8_t* buf)
1098 {
1099     int max_len = ube16_to_cpu(buf + 8);
1100 
1101     cpu_to_ube16(buf, 0);
1102     /* no current LBA */
1103     buf[2] = 0;
1104     buf[3] = 0;
1105     buf[4] = 0;
1106     buf[5] = 1;
1107     cpu_to_ube16(buf + 6, 0);
1108     ide_atapi_cmd_reply(s, 8, max_len);
1109 }
1110 
1111 static void cmd_read_toc_pma_atip(IDEState *s, uint8_t* buf)
1112 {
1113     int format, msf, start_track, len;
1114     int max_len;
1115     uint64_t total_sectors = s->nb_sectors >> 2;
1116 
1117     max_len = ube16_to_cpu(buf + 7);
1118     format = buf[9] >> 6;
1119     msf = (buf[1] >> 1) & 1;
1120     start_track = buf[6];
1121 
1122     switch(format) {
1123     case 0:
1124         len = cdrom_read_toc(total_sectors, buf, msf, start_track);
1125         if (len < 0)
1126             goto error_cmd;
1127         ide_atapi_cmd_reply(s, len, max_len);
1128         break;
1129     case 1:
1130         /* multi session : only a single session defined */
1131         memset(buf, 0, 12);
1132         buf[1] = 0x0a;
1133         buf[2] = 0x01;
1134         buf[3] = 0x01;
1135         ide_atapi_cmd_reply(s, 12, max_len);
1136         break;
1137     case 2:
1138         len = cdrom_read_toc_raw(total_sectors, buf, msf, start_track);
1139         if (len < 0)
1140             goto error_cmd;
1141         ide_atapi_cmd_reply(s, len, max_len);
1142         break;
1143     default:
1144     error_cmd:
1145         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1146                             ASC_INV_FIELD_IN_CMD_PACKET);
1147     }
1148 }
1149 
1150 static void cmd_read_cdvd_capacity(IDEState *s, uint8_t* buf)
1151 {
1152     uint64_t total_sectors = s->nb_sectors >> 2;
1153 
1154     /* NOTE: it is really the number of sectors minus 1 */
1155     cpu_to_ube32(buf, total_sectors - 1);
1156     cpu_to_ube32(buf + 4, 2048);
1157     ide_atapi_cmd_reply(s, 8, 8);
1158 }
1159 
1160 static void cmd_read_disc_information(IDEState *s, uint8_t* buf)
1161 {
1162     uint8_t type = buf[1] & 7;
1163     uint32_t max_len = ube16_to_cpu(buf + 7);
1164 
1165     /* Types 1/2 are only defined for Blu-Ray.  */
1166     if (type != 0) {
1167         ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1168                             ASC_INV_FIELD_IN_CMD_PACKET);
1169         return;
1170     }
1171 
1172     memset(buf, 0, 34);
1173     buf[1] = 32;
1174     buf[2] = 0xe; /* last session complete, disc finalized */
1175     buf[3] = 1;   /* first track on disc */
1176     buf[4] = 1;   /* # of sessions */
1177     buf[5] = 1;   /* first track of last session */
1178     buf[6] = 1;   /* last track of last session */
1179     buf[7] = 0x20; /* unrestricted use */
1180     buf[8] = 0x00; /* CD-ROM or DVD-ROM */
1181     /* 9-10-11: most significant byte corresponding bytes 4-5-6 */
1182     /* 12-23: not meaningful for CD-ROM or DVD-ROM */
1183     /* 24-31: disc bar code */
1184     /* 32: disc application code */
1185     /* 33: number of OPC tables */
1186 
1187     ide_atapi_cmd_reply(s, 34, max_len);
1188 }
1189 
1190 static void cmd_read_dvd_structure(IDEState *s, uint8_t* buf)
1191 {
1192     int max_len;
1193     int media = buf[1];
1194     int format = buf[7];
1195     int ret;
1196 
1197     max_len = ube16_to_cpu(buf + 8);
1198 
1199     if (format < 0xff) {
1200         if (media_is_cd(s)) {
1201             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1202                                 ASC_INCOMPATIBLE_FORMAT);
1203             return;
1204         } else if (!media_present(s)) {
1205             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1206                                 ASC_INV_FIELD_IN_CMD_PACKET);
1207             return;
1208         }
1209     }
1210 
1211     memset(buf, 0, max_len > IDE_DMA_BUF_SECTORS * 512 + 4 ?
1212            IDE_DMA_BUF_SECTORS * 512 + 4 : max_len);
1213 
1214     switch (format) {
1215         case 0x00 ... 0x7f:
1216         case 0xff:
1217             if (media == 0) {
1218                 ret = ide_dvd_read_structure(s, format, buf, buf);
1219 
1220                 if (ret < 0) {
1221                     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, -ret);
1222                 } else {
1223                     ide_atapi_cmd_reply(s, ret, max_len);
1224                 }
1225 
1226                 break;
1227             }
1228             /* TODO: BD support, fall through for now */
1229 
1230         /* Generic disk structures */
1231         case 0x80: /* TODO: AACS volume identifier */
1232         case 0x81: /* TODO: AACS media serial number */
1233         case 0x82: /* TODO: AACS media identifier */
1234         case 0x83: /* TODO: AACS media key block */
1235         case 0x90: /* TODO: List of recognized format layers */
1236         case 0xc0: /* TODO: Write protection status */
1237         default:
1238             ide_atapi_cmd_error(s, ILLEGAL_REQUEST,
1239                                 ASC_INV_FIELD_IN_CMD_PACKET);
1240             break;
1241     }
1242 }
1243 
1244 static void cmd_set_speed(IDEState *s, uint8_t* buf)
1245 {
1246     ide_atapi_cmd_ok(s);
1247 }
1248 
1249 enum {
1250     /*
1251      * Only commands flagged as ALLOW_UA are allowed to run under a
1252      * unit attention condition. (See MMC-5, section 4.1.6.1)
1253      */
1254     ALLOW_UA = 0x01,
1255 
1256     /*
1257      * Commands flagged with CHECK_READY can only execute if a medium is present.
1258      * Otherwise they report the Not Ready Condition. (See MMC-5, section
1259      * 4.1.8)
1260      */
1261     CHECK_READY = 0x02,
1262 
1263     /*
1264      * Commands flagged with NONDATA do not in any circumstances return
1265      * any data via ide_atapi_cmd_reply. These commands are exempt from
1266      * the normal byte_count_limit constraints.
1267      * See ATA8-ACS3 "7.21.5 Byte Count Limit"
1268      */
1269     NONDATA = 0x04,
1270 
1271     /*
1272      * CONDDATA implies a command that transfers data only conditionally based
1273      * on the presence of suboptions. It should be exempt from the BCL check at
1274      * command validation time, but it needs to be checked at the command
1275      * handler level instead.
1276      */
1277     CONDDATA = 0x08,
1278 };
1279 
1280 static const struct AtapiCmd {
1281     void (*handler)(IDEState *s, uint8_t *buf);
1282     int flags;
1283 } atapi_cmd_table[0x100] = {
1284     [ 0x00 ] = { cmd_test_unit_ready,               CHECK_READY | NONDATA },
1285     [ 0x03 ] = { cmd_request_sense,                 ALLOW_UA },
1286     [ 0x12 ] = { cmd_inquiry,                       ALLOW_UA },
1287     [ 0x1b ] = { cmd_start_stop_unit,               NONDATA }, /* [1] */
1288     [ 0x1e ] = { cmd_prevent_allow_medium_removal,  NONDATA },
1289     [ 0x25 ] = { cmd_read_cdvd_capacity,            CHECK_READY },
1290     [ 0x28 ] = { cmd_read, /* (10) */               CHECK_READY },
1291     [ 0x2b ] = { cmd_seek,                          CHECK_READY | NONDATA },
1292     [ 0x43 ] = { cmd_read_toc_pma_atip,             CHECK_READY },
1293     [ 0x46 ] = { cmd_get_configuration,             ALLOW_UA },
1294     [ 0x4a ] = { cmd_get_event_status_notification, ALLOW_UA },
1295     [ 0x51 ] = { cmd_read_disc_information,         CHECK_READY },
1296     [ 0x5a ] = { cmd_mode_sense, /* (10) */         0 },
1297     [ 0xa8 ] = { cmd_read, /* (12) */               CHECK_READY },
1298     [ 0xad ] = { cmd_read_dvd_structure,            CHECK_READY },
1299     [ 0xbb ] = { cmd_set_speed,                     NONDATA },
1300     [ 0xbd ] = { cmd_mechanism_status,              0 },
1301     [ 0xbe ] = { cmd_read_cd,                       CHECK_READY | CONDDATA },
1302     /* [1] handler detects and reports not ready condition itself */
1303 };
1304 
1305 void ide_atapi_cmd(IDEState *s)
1306 {
1307     uint8_t *buf = s->io_buffer;
1308     const struct AtapiCmd *cmd = &atapi_cmd_table[s->io_buffer[0]];
1309 
1310     trace_ide_atapi_cmd(s, s->io_buffer[0]);
1311 
1312     if (trace_event_get_state_backends(TRACE_IDE_ATAPI_CMD_PACKET)) {
1313         /* Each pretty-printed byte needs two bytes and a space; */
1314         char *ppacket = g_malloc(ATAPI_PACKET_SIZE * 3 + 1);
1315         int i;
1316         for (i = 0; i < ATAPI_PACKET_SIZE; i++) {
1317             sprintf(ppacket + (i * 3), "%02x ", buf[i]);
1318         }
1319         trace_ide_atapi_cmd_packet(s, s->lcyl | (s->hcyl << 8), ppacket);
1320         g_free(ppacket);
1321     }
1322 
1323     /*
1324      * If there's a UNIT_ATTENTION condition pending, only command flagged with
1325      * ALLOW_UA are allowed to complete. with other commands getting a CHECK
1326      * condition response unless a higher priority status, defined by the drive
1327      * here, is pending.
1328      */
1329     if (s->sense_key == UNIT_ATTENTION && !(cmd->flags & ALLOW_UA)) {
1330         ide_atapi_cmd_check_status(s);
1331         return;
1332     }
1333     /*
1334      * When a CD gets changed, we have to report an ejected state and
1335      * then a loaded state to guests so that they detect tray
1336      * open/close and media change events.  Guests that do not use
1337      * GET_EVENT_STATUS_NOTIFICATION to detect such tray open/close
1338      * states rely on this behavior.
1339      */
1340     if (!(cmd->flags & ALLOW_UA) &&
1341         !s->tray_open && blk_is_inserted(s->blk) && s->cdrom_changed) {
1342 
1343         if (s->cdrom_changed == 1) {
1344             ide_atapi_cmd_error(s, NOT_READY, ASC_MEDIUM_NOT_PRESENT);
1345             s->cdrom_changed = 2;
1346         } else {
1347             ide_atapi_cmd_error(s, UNIT_ATTENTION, ASC_MEDIUM_MAY_HAVE_CHANGED);
1348             s->cdrom_changed = 0;
1349         }
1350 
1351         return;
1352     }
1353 
1354     /* Report a Not Ready condition if appropriate for the command */
1355     if ((cmd->flags & CHECK_READY) &&
1356         (!media_present(s) || !blk_is_inserted(s->blk)))
1357     {
1358         ide_atapi_cmd_error(s, NOT_READY, ASC_MEDIUM_NOT_PRESENT);
1359         return;
1360     }
1361 
1362     /* Commands that don't transfer DATA permit the byte_count_limit to be 0.
1363      * If this is a data-transferring PIO command and BCL is 0,
1364      * we abort at the /ATA/ level, not the ATAPI level.
1365      * See ATA8 ACS3 section 7.17.6.49 and 7.21.5 */
1366     if (cmd->handler && !(cmd->flags & (NONDATA | CONDDATA))) {
1367         if (!validate_bcl(s)) {
1368             return;
1369         }
1370     }
1371 
1372     /* Execute the command */
1373     if (cmd->handler) {
1374         cmd->handler(s, buf);
1375         return;
1376     }
1377 
1378     ide_atapi_cmd_error(s, ILLEGAL_REQUEST, ASC_ILLEGAL_OPCODE);
1379 }
1380