1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * sr.c Copyright (C) 1992 David Giller
4 * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
5 *
6 * adapted from:
7 * sd.c Copyright (C) 1992 Drew Eckhardt
8 * Linux scsi disk driver by
9 * Drew Eckhardt <drew@colorado.edu>
10 *
11 * Modified by Eric Youngdale ericy@andante.org to
12 * add scatter-gather, multiple outstanding request, and other
13 * enhancements.
14 *
15 * Modified by Eric Youngdale eric@andante.org to support loadable
16 * low-level scsi drivers.
17 *
18 * Modified by Thomas Quinot thomas@melchior.cuivre.fdn.fr to
19 * provide auto-eject.
20 *
21 * Modified by Gerd Knorr <kraxel@cs.tu-berlin.de> to support the
22 * generic cdrom interface
23 *
24 * Modified by Jens Axboe <axboe@suse.de> - Uniform sr_packet()
25 * interface, capabilities probe additions, ioctl cleanups, etc.
26 *
27 * Modified by Richard Gooch <rgooch@atnf.csiro.au> to support devfs
28 *
29 * Modified by Jens Axboe <axboe@suse.de> - support DVD-RAM
30 * transparently and lose the GHOST hack
31 *
32 * Modified by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
33 * check resource allocation in sr_init and some cleanups
34 */
35
36 #include <linux/module.h>
37 #include <linux/fs.h>
38 #include <linux/kernel.h>
39 #include <linux/mm.h>
40 #include <linux/bio.h>
41 #include <linux/compat.h>
42 #include <linux/string.h>
43 #include <linux/errno.h>
44 #include <linux/cdrom.h>
45 #include <linux/interrupt.h>
46 #include <linux/init.h>
47 #include <linux/blkdev.h>
48 #include <linux/blk-pm.h>
49 #include <linux/mutex.h>
50 #include <linux/slab.h>
51 #include <linux/pm_runtime.h>
52 #include <linux/uaccess.h>
53
54 #include <asm/unaligned.h>
55
56 #include <scsi/scsi.h>
57 #include <scsi/scsi_dbg.h>
58 #include <scsi/scsi_device.h>
59 #include <scsi/scsi_driver.h>
60 #include <scsi/scsi_cmnd.h>
61 #include <scsi/scsi_eh.h>
62 #include <scsi/scsi_host.h>
63 #include <scsi/scsi_ioctl.h> /* For the door lock/unlock commands */
64
65 #include "scsi_logging.h"
66 #include "sr.h"
67
68
69 MODULE_DESCRIPTION("SCSI cdrom (sr) driver");
70 MODULE_LICENSE("GPL");
71 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR);
72 MODULE_ALIAS_SCSI_DEVICE(TYPE_ROM);
73 MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
74
75 #define SR_DISKS 256
76
77 #define SR_CAPABILITIES \
78 (CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|CDC_SELECT_SPEED| \
79 CDC_SELECT_DISC|CDC_MULTI_SESSION|CDC_MCN|CDC_MEDIA_CHANGED| \
80 CDC_PLAY_AUDIO|CDC_RESET|CDC_DRIVE_STATUS| \
81 CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_DVD_RAM|CDC_GENERIC_PACKET| \
82 CDC_MRW|CDC_MRW_W|CDC_RAM)
83
84 static int sr_probe(struct device *);
85 static int sr_remove(struct device *);
86 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt);
87 static int sr_done(struct scsi_cmnd *);
88 static int sr_runtime_suspend(struct device *dev);
89
90 static const struct dev_pm_ops sr_pm_ops = {
91 .runtime_suspend = sr_runtime_suspend,
92 };
93
94 static struct scsi_driver sr_template = {
95 .gendrv = {
96 .name = "sr",
97 .owner = THIS_MODULE,
98 .probe = sr_probe,
99 .remove = sr_remove,
100 .pm = &sr_pm_ops,
101 },
102 .init_command = sr_init_command,
103 .done = sr_done,
104 };
105
106 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
107 static DEFINE_SPINLOCK(sr_index_lock);
108
109 /* This semaphore is used to mediate the 0->1 reference get in the
110 * face of object destruction (i.e. we can't allow a get on an
111 * object after last put) */
112 static DEFINE_MUTEX(sr_ref_mutex);
113
114 static int sr_open(struct cdrom_device_info *, int);
115 static void sr_release(struct cdrom_device_info *);
116
117 static void get_sectorsize(struct scsi_cd *);
118 static void get_capabilities(struct scsi_cd *);
119
120 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
121 unsigned int clearing, int slot);
122 static int sr_packet(struct cdrom_device_info *, struct packet_command *);
123
124 static const struct cdrom_device_ops sr_dops = {
125 .open = sr_open,
126 .release = sr_release,
127 .drive_status = sr_drive_status,
128 .check_events = sr_check_events,
129 .tray_move = sr_tray_move,
130 .lock_door = sr_lock_door,
131 .select_speed = sr_select_speed,
132 .get_last_session = sr_get_last_session,
133 .get_mcn = sr_get_mcn,
134 .reset = sr_reset,
135 .audio_ioctl = sr_audio_ioctl,
136 .capability = SR_CAPABILITIES,
137 .generic_packet = sr_packet,
138 };
139
140 static void sr_kref_release(struct kref *kref);
141
scsi_cd(struct gendisk * disk)142 static inline struct scsi_cd *scsi_cd(struct gendisk *disk)
143 {
144 return container_of(disk->private_data, struct scsi_cd, driver);
145 }
146
sr_runtime_suspend(struct device * dev)147 static int sr_runtime_suspend(struct device *dev)
148 {
149 struct scsi_cd *cd = dev_get_drvdata(dev);
150
151 if (!cd) /* E.g.: runtime suspend following sr_remove() */
152 return 0;
153
154 if (cd->media_present)
155 return -EBUSY;
156 else
157 return 0;
158 }
159
160 /*
161 * The get and put routines for the struct scsi_cd. Note this entity
162 * has a scsi_device pointer and owns a reference to this.
163 */
scsi_cd_get(struct gendisk * disk)164 static inline struct scsi_cd *scsi_cd_get(struct gendisk *disk)
165 {
166 struct scsi_cd *cd = NULL;
167
168 mutex_lock(&sr_ref_mutex);
169 if (disk->private_data == NULL)
170 goto out;
171 cd = scsi_cd(disk);
172 kref_get(&cd->kref);
173 if (scsi_device_get(cd->device)) {
174 kref_put(&cd->kref, sr_kref_release);
175 cd = NULL;
176 }
177 out:
178 mutex_unlock(&sr_ref_mutex);
179 return cd;
180 }
181
scsi_cd_put(struct scsi_cd * cd)182 static void scsi_cd_put(struct scsi_cd *cd)
183 {
184 struct scsi_device *sdev = cd->device;
185
186 mutex_lock(&sr_ref_mutex);
187 kref_put(&cd->kref, sr_kref_release);
188 scsi_device_put(sdev);
189 mutex_unlock(&sr_ref_mutex);
190 }
191
sr_get_events(struct scsi_device * sdev)192 static unsigned int sr_get_events(struct scsi_device *sdev)
193 {
194 u8 buf[8];
195 u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION,
196 1, /* polled */
197 0, 0, /* reserved */
198 1 << 4, /* notification class: media */
199 0, 0, /* reserved */
200 0, sizeof(buf), /* allocation length */
201 0, /* control */
202 };
203 struct event_header *eh = (void *)buf;
204 struct media_event_desc *med = (void *)(buf + 4);
205 struct scsi_sense_hdr sshdr;
206 int result;
207
208 result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf),
209 &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL);
210 if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
211 return DISK_EVENT_MEDIA_CHANGE;
212
213 if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
214 return 0;
215
216 if (eh->nea || eh->notification_class != 0x4)
217 return 0;
218
219 if (med->media_event_code == 1)
220 return DISK_EVENT_EJECT_REQUEST;
221 else if (med->media_event_code == 2)
222 return DISK_EVENT_MEDIA_CHANGE;
223 else if (med->media_event_code == 3)
224 return DISK_EVENT_MEDIA_CHANGE;
225 return 0;
226 }
227
228 /*
229 * This function checks to see if the media has been changed or eject
230 * button has been pressed. It is possible that we have already
231 * sensed a change, or the drive may have sensed one and not yet
232 * reported it. The past events are accumulated in sdev->changed and
233 * returned together with the current state.
234 */
sr_check_events(struct cdrom_device_info * cdi,unsigned int clearing,int slot)235 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
236 unsigned int clearing, int slot)
237 {
238 struct scsi_cd *cd = cdi->handle;
239 bool last_present;
240 struct scsi_sense_hdr sshdr;
241 unsigned int events;
242 int ret;
243
244 /* no changer support */
245 if (CDSL_CURRENT != slot)
246 return 0;
247
248 events = sr_get_events(cd->device);
249 cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE;
250
251 /*
252 * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree
253 * for several times in a row. We rely on TUR only for this likely
254 * broken device, to prevent generating incorrect media changed
255 * events for every open().
256 */
257 if (cd->ignore_get_event) {
258 events &= ~DISK_EVENT_MEDIA_CHANGE;
259 goto do_tur;
260 }
261
262 /*
263 * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE
264 * is being cleared. Note that there are devices which hang
265 * if asked to execute TUR repeatedly.
266 */
267 if (cd->device->changed) {
268 events |= DISK_EVENT_MEDIA_CHANGE;
269 cd->device->changed = 0;
270 cd->tur_changed = true;
271 }
272
273 if (!(clearing & DISK_EVENT_MEDIA_CHANGE))
274 return events;
275 do_tur:
276 /* let's see whether the media is there with TUR */
277 last_present = cd->media_present;
278 ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
279
280 /*
281 * Media is considered to be present if TUR succeeds or fails with
282 * sense data indicating something other than media-not-present
283 * (ASC 0x3a).
284 */
285 cd->media_present = scsi_status_is_good(ret) ||
286 (scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a);
287
288 if (last_present != cd->media_present)
289 cd->device->changed = 1;
290
291 if (cd->device->changed) {
292 events |= DISK_EVENT_MEDIA_CHANGE;
293 cd->device->changed = 0;
294 cd->tur_changed = true;
295 }
296
297 if (cd->ignore_get_event)
298 return events;
299
300 /* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */
301 if (!cd->tur_changed) {
302 if (cd->get_event_changed) {
303 if (cd->tur_mismatch++ > 8) {
304 sr_printk(KERN_WARNING, cd,
305 "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n");
306 cd->ignore_get_event = true;
307 }
308 } else {
309 cd->tur_mismatch = 0;
310 }
311 }
312 cd->tur_changed = false;
313 cd->get_event_changed = false;
314
315 return events;
316 }
317
318 /*
319 * sr_done is the interrupt routine for the device driver.
320 *
321 * It will be notified on the end of a SCSI read / write, and will take one
322 * of several actions based on success or failure.
323 */
sr_done(struct scsi_cmnd * SCpnt)324 static int sr_done(struct scsi_cmnd *SCpnt)
325 {
326 int result = SCpnt->result;
327 int this_count = scsi_bufflen(SCpnt);
328 int good_bytes = (result == 0 ? this_count : 0);
329 int block_sectors = 0;
330 long error_sector;
331 struct scsi_cd *cd = scsi_cd(SCpnt->request->rq_disk);
332
333 #ifdef DEBUG
334 scmd_printk(KERN_INFO, SCpnt, "done: %x\n", result);
335 #endif
336
337 /*
338 * Handle MEDIUM ERRORs or VOLUME OVERFLOWs that indicate partial
339 * success. Since this is a relatively rare error condition, no
340 * care is taken to avoid unnecessary additional work such as
341 * memcpy's that could be avoided.
342 */
343 if (driver_byte(result) != 0 && /* An error occurred */
344 (SCpnt->sense_buffer[0] & 0x7f) == 0x70) { /* Sense current */
345 switch (SCpnt->sense_buffer[2]) {
346 case MEDIUM_ERROR:
347 case VOLUME_OVERFLOW:
348 case ILLEGAL_REQUEST:
349 if (!(SCpnt->sense_buffer[0] & 0x90))
350 break;
351 error_sector =
352 get_unaligned_be32(&SCpnt->sense_buffer[3]);
353 if (SCpnt->request->bio != NULL)
354 block_sectors =
355 bio_sectors(SCpnt->request->bio);
356 if (block_sectors < 4)
357 block_sectors = 4;
358 if (cd->device->sector_size == 2048)
359 error_sector <<= 2;
360 error_sector &= ~(block_sectors - 1);
361 good_bytes = (error_sector -
362 blk_rq_pos(SCpnt->request)) << 9;
363 if (good_bytes < 0 || good_bytes >= this_count)
364 good_bytes = 0;
365 /*
366 * The SCSI specification allows for the value
367 * returned by READ CAPACITY to be up to 75 2K
368 * sectors past the last readable block.
369 * Therefore, if we hit a medium error within the
370 * last 75 2K sectors, we decrease the saved size
371 * value.
372 */
373 if (error_sector < get_capacity(cd->disk) &&
374 cd->capacity - error_sector < 4 * 75)
375 set_capacity(cd->disk, error_sector);
376 break;
377
378 case RECOVERED_ERROR:
379 good_bytes = this_count;
380 break;
381
382 default:
383 break;
384 }
385 }
386
387 return good_bytes;
388 }
389
sr_init_command(struct scsi_cmnd * SCpnt)390 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
391 {
392 int block = 0, this_count, s_size;
393 struct scsi_cd *cd;
394 struct request *rq = SCpnt->request;
395 blk_status_t ret;
396
397 ret = scsi_alloc_sgtables(SCpnt);
398 if (ret != BLK_STS_OK)
399 return ret;
400 cd = scsi_cd(rq->rq_disk);
401
402 SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
403 "Doing sr request, block = %d\n", block));
404
405 if (!cd->device || !scsi_device_online(cd->device)) {
406 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
407 "Finishing %u sectors\n", blk_rq_sectors(rq)));
408 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
409 "Retry with 0x%p\n", SCpnt));
410 goto out;
411 }
412
413 if (cd->device->changed) {
414 /*
415 * quietly refuse to do anything to a changed disc until the
416 * changed bit has been reset
417 */
418 goto out;
419 }
420
421 /*
422 * we do lazy blocksize switching (when reading XA sectors,
423 * see CDROMREADMODE2 ioctl)
424 */
425 s_size = cd->device->sector_size;
426 if (s_size > 2048) {
427 if (!in_interrupt())
428 sr_set_blocklength(cd, 2048);
429 else
430 scmd_printk(KERN_INFO, SCpnt,
431 "can't switch blocksize: in interrupt\n");
432 }
433
434 if (s_size != 512 && s_size != 1024 && s_size != 2048) {
435 scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
436 goto out;
437 }
438
439 switch (req_op(rq)) {
440 case REQ_OP_WRITE:
441 if (!cd->writeable)
442 goto out;
443 SCpnt->cmnd[0] = WRITE_10;
444 cd->cdi.media_written = 1;
445 break;
446 case REQ_OP_READ:
447 SCpnt->cmnd[0] = READ_10;
448 break;
449 default:
450 blk_dump_rq_flags(rq, "Unknown sr command");
451 goto out;
452 }
453
454 {
455 struct scatterlist *sg;
456 int i, size = 0, sg_count = scsi_sg_count(SCpnt);
457
458 scsi_for_each_sg(SCpnt, sg, sg_count, i)
459 size += sg->length;
460
461 if (size != scsi_bufflen(SCpnt)) {
462 scmd_printk(KERN_ERR, SCpnt,
463 "mismatch count %d, bytes %d\n",
464 size, scsi_bufflen(SCpnt));
465 if (scsi_bufflen(SCpnt) > size)
466 SCpnt->sdb.length = size;
467 }
468 }
469
470 /*
471 * request doesn't start on hw block boundary, add scatter pads
472 */
473 if (((unsigned int)blk_rq_pos(rq) % (s_size >> 9)) ||
474 (scsi_bufflen(SCpnt) % s_size)) {
475 scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
476 goto out;
477 }
478
479 this_count = (scsi_bufflen(SCpnt) >> 9) / (s_size >> 9);
480
481
482 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
483 "%s %d/%u 512 byte blocks.\n",
484 (rq_data_dir(rq) == WRITE) ?
485 "writing" : "reading",
486 this_count, blk_rq_sectors(rq)));
487
488 SCpnt->cmnd[1] = 0;
489 block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);
490
491 if (this_count > 0xffff) {
492 this_count = 0xffff;
493 SCpnt->sdb.length = this_count * s_size;
494 }
495
496 put_unaligned_be32(block, &SCpnt->cmnd[2]);
497 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
498 put_unaligned_be16(this_count, &SCpnt->cmnd[7]);
499
500 /*
501 * We shouldn't disconnect in the middle of a sector, so with a dumb
502 * host adapter, it's safe to assume that we can at least transfer
503 * this many bytes between each connect / disconnect.
504 */
505 SCpnt->transfersize = cd->device->sector_size;
506 SCpnt->underflow = this_count << 9;
507 SCpnt->allowed = MAX_RETRIES;
508 SCpnt->cmd_len = 10;
509
510 /*
511 * This indicates that the command is ready from our end to be queued.
512 */
513 return BLK_STS_OK;
514 out:
515 scsi_free_sgtables(SCpnt);
516 return BLK_STS_IOERR;
517 }
518
sr_revalidate_disk(struct scsi_cd * cd)519 static void sr_revalidate_disk(struct scsi_cd *cd)
520 {
521 struct scsi_sense_hdr sshdr;
522
523 /* if the unit is not ready, nothing more to do */
524 if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr))
525 return;
526 sr_cd_check(&cd->cdi);
527 get_sectorsize(cd);
528 }
529
sr_block_open(struct block_device * bdev,fmode_t mode)530 static int sr_block_open(struct block_device *bdev, fmode_t mode)
531 {
532 struct scsi_cd *cd;
533 struct scsi_device *sdev;
534 int ret = -ENXIO;
535
536 cd = scsi_cd_get(bdev->bd_disk);
537 if (!cd)
538 goto out;
539
540 sdev = cd->device;
541 scsi_autopm_get_device(sdev);
542 if (bdev_check_media_change(bdev))
543 sr_revalidate_disk(cd);
544
545 mutex_lock(&cd->lock);
546 ret = cdrom_open(&cd->cdi, bdev, mode);
547 mutex_unlock(&cd->lock);
548
549 scsi_autopm_put_device(sdev);
550 if (ret)
551 scsi_cd_put(cd);
552
553 out:
554 return ret;
555 }
556
sr_block_release(struct gendisk * disk,fmode_t mode)557 static void sr_block_release(struct gendisk *disk, fmode_t mode)
558 {
559 struct scsi_cd *cd = scsi_cd(disk);
560
561 mutex_lock(&cd->lock);
562 cdrom_release(&cd->cdi, mode);
563 mutex_unlock(&cd->lock);
564
565 scsi_cd_put(cd);
566 }
567
sr_block_ioctl(struct block_device * bdev,fmode_t mode,unsigned cmd,unsigned long arg)568 static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
569 unsigned long arg)
570 {
571 struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
572 struct scsi_device *sdev = cd->device;
573 void __user *argp = (void __user *)arg;
574 int ret;
575
576 mutex_lock(&cd->lock);
577
578 ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
579 (mode & FMODE_NDELAY) != 0);
580 if (ret)
581 goto out;
582
583 scsi_autopm_get_device(sdev);
584
585 /*
586 * Send SCSI addressing ioctls directly to mid level, send other
587 * ioctls to cdrom/block level.
588 */
589 switch (cmd) {
590 case SCSI_IOCTL_GET_IDLUN:
591 case SCSI_IOCTL_GET_BUS_NUMBER:
592 ret = scsi_ioctl(sdev, cmd, argp);
593 goto put;
594 }
595
596 ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
597 if (ret != -ENOSYS)
598 goto put;
599
600 ret = scsi_ioctl(sdev, cmd, argp);
601
602 put:
603 scsi_autopm_put_device(sdev);
604
605 out:
606 mutex_unlock(&cd->lock);
607 return ret;
608 }
609
610 #ifdef CONFIG_COMPAT
sr_block_compat_ioctl(struct block_device * bdev,fmode_t mode,unsigned cmd,unsigned long arg)611 static int sr_block_compat_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
612 unsigned long arg)
613 {
614 struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
615 struct scsi_device *sdev = cd->device;
616 void __user *argp = compat_ptr(arg);
617 int ret;
618
619 mutex_lock(&cd->lock);
620
621 ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
622 (mode & FMODE_NDELAY) != 0);
623 if (ret)
624 goto out;
625
626 scsi_autopm_get_device(sdev);
627
628 /*
629 * Send SCSI addressing ioctls directly to mid level, send other
630 * ioctls to cdrom/block level.
631 */
632 switch (cmd) {
633 case SCSI_IOCTL_GET_IDLUN:
634 case SCSI_IOCTL_GET_BUS_NUMBER:
635 ret = scsi_compat_ioctl(sdev, cmd, argp);
636 goto put;
637 }
638
639 ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, (unsigned long)argp);
640 if (ret != -ENOSYS)
641 goto put;
642
643 ret = scsi_compat_ioctl(sdev, cmd, argp);
644
645 put:
646 scsi_autopm_put_device(sdev);
647
648 out:
649 mutex_unlock(&cd->lock);
650 return ret;
651
652 }
653 #endif
654
sr_block_check_events(struct gendisk * disk,unsigned int clearing)655 static unsigned int sr_block_check_events(struct gendisk *disk,
656 unsigned int clearing)
657 {
658 unsigned int ret = 0;
659 struct scsi_cd *cd;
660
661 cd = scsi_cd_get(disk);
662 if (!cd)
663 return 0;
664
665 if (!atomic_read(&cd->device->disk_events_disable_depth))
666 ret = cdrom_check_events(&cd->cdi, clearing);
667
668 scsi_cd_put(cd);
669 return ret;
670 }
671
672 static const struct block_device_operations sr_bdops =
673 {
674 .owner = THIS_MODULE,
675 .open = sr_block_open,
676 .release = sr_block_release,
677 .ioctl = sr_block_ioctl,
678 #ifdef CONFIG_COMPAT
679 .compat_ioctl = sr_block_compat_ioctl,
680 #endif
681 .check_events = sr_block_check_events,
682 };
683
sr_open(struct cdrom_device_info * cdi,int purpose)684 static int sr_open(struct cdrom_device_info *cdi, int purpose)
685 {
686 struct scsi_cd *cd = cdi->handle;
687 struct scsi_device *sdev = cd->device;
688 int retval;
689
690 /*
691 * If the device is in error recovery, wait until it is done.
692 * If the device is offline, then disallow any access to it.
693 */
694 retval = -ENXIO;
695 if (!scsi_block_when_processing_errors(sdev))
696 goto error_out;
697
698 return 0;
699
700 error_out:
701 return retval;
702 }
703
sr_release(struct cdrom_device_info * cdi)704 static void sr_release(struct cdrom_device_info *cdi)
705 {
706 struct scsi_cd *cd = cdi->handle;
707
708 if (cd->device->sector_size > 2048)
709 sr_set_blocklength(cd, 2048);
710
711 }
712
sr_probe(struct device * dev)713 static int sr_probe(struct device *dev)
714 {
715 struct scsi_device *sdev = to_scsi_device(dev);
716 struct gendisk *disk;
717 struct scsi_cd *cd;
718 int minor, error;
719
720 scsi_autopm_get_device(sdev);
721 error = -ENODEV;
722 if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)
723 goto fail;
724
725 error = -ENOMEM;
726 cd = kzalloc(sizeof(*cd), GFP_KERNEL);
727 if (!cd)
728 goto fail;
729
730 kref_init(&cd->kref);
731
732 disk = alloc_disk(1);
733 if (!disk)
734 goto fail_free;
735 mutex_init(&cd->lock);
736
737 spin_lock(&sr_index_lock);
738 minor = find_first_zero_bit(sr_index_bits, SR_DISKS);
739 if (minor == SR_DISKS) {
740 spin_unlock(&sr_index_lock);
741 error = -EBUSY;
742 goto fail_put;
743 }
744 __set_bit(minor, sr_index_bits);
745 spin_unlock(&sr_index_lock);
746
747 disk->major = SCSI_CDROM_MAJOR;
748 disk->first_minor = minor;
749 sprintf(disk->disk_name, "sr%d", minor);
750 disk->fops = &sr_bdops;
751 disk->flags = GENHD_FL_CD | GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE;
752 disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST;
753 disk->event_flags = DISK_EVENT_FLAG_POLL | DISK_EVENT_FLAG_UEVENT;
754
755 blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
756
757 cd->device = sdev;
758 cd->disk = disk;
759 cd->driver = &sr_template;
760 cd->disk = disk;
761 cd->capacity = 0x1fffff;
762 cd->device->changed = 1; /* force recheck CD type */
763 cd->media_present = 1;
764 cd->use = 1;
765 cd->readcd_known = 0;
766 cd->readcd_cdda = 0;
767
768 cd->cdi.ops = &sr_dops;
769 cd->cdi.handle = cd;
770 cd->cdi.mask = 0;
771 cd->cdi.capacity = 1;
772 sprintf(cd->cdi.name, "sr%d", minor);
773
774 sdev->sector_size = 2048; /* A guess, just in case */
775
776 /* FIXME: need to handle a get_capabilities failure properly ?? */
777 get_capabilities(cd);
778 sr_vendor_init(cd);
779
780 set_capacity(disk, cd->capacity);
781 disk->private_data = &cd->driver;
782 disk->queue = sdev->request_queue;
783
784 if (register_cdrom(disk, &cd->cdi))
785 goto fail_minor;
786
787 /*
788 * Initialize block layer runtime PM stuffs before the
789 * periodic event checking request gets started in add_disk.
790 */
791 blk_pm_runtime_init(sdev->request_queue, dev);
792
793 dev_set_drvdata(dev, cd);
794 disk->flags |= GENHD_FL_REMOVABLE;
795 sr_revalidate_disk(cd);
796 device_add_disk(&sdev->sdev_gendev, disk, NULL);
797
798 sdev_printk(KERN_DEBUG, sdev,
799 "Attached scsi CD-ROM %s\n", cd->cdi.name);
800 scsi_autopm_put_device(cd->device);
801
802 return 0;
803
804 fail_minor:
805 spin_lock(&sr_index_lock);
806 clear_bit(minor, sr_index_bits);
807 spin_unlock(&sr_index_lock);
808 fail_put:
809 put_disk(disk);
810 mutex_destroy(&cd->lock);
811 fail_free:
812 kfree(cd);
813 fail:
814 scsi_autopm_put_device(sdev);
815 return error;
816 }
817
818
get_sectorsize(struct scsi_cd * cd)819 static void get_sectorsize(struct scsi_cd *cd)
820 {
821 unsigned char cmd[10];
822 unsigned char buffer[8];
823 int the_result, retries = 3;
824 int sector_size;
825 struct request_queue *queue;
826
827 do {
828 cmd[0] = READ_CAPACITY;
829 memset((void *) &cmd[1], 0, 9);
830 memset(buffer, 0, sizeof(buffer));
831
832 /* Do the command and wait.. */
833 the_result = scsi_execute_req(cd->device, cmd, DMA_FROM_DEVICE,
834 buffer, sizeof(buffer), NULL,
835 SR_TIMEOUT, MAX_RETRIES, NULL);
836
837 retries--;
838
839 } while (the_result && retries);
840
841
842 if (the_result) {
843 cd->capacity = 0x1fffff;
844 sector_size = 2048; /* A guess, just in case */
845 } else {
846 long last_written;
847
848 cd->capacity = 1 + get_unaligned_be32(&buffer[0]);
849 /*
850 * READ_CAPACITY doesn't return the correct size on
851 * certain UDF media. If last_written is larger, use
852 * it instead.
853 *
854 * http://bugzilla.kernel.org/show_bug.cgi?id=9668
855 */
856 if (!cdrom_get_last_written(&cd->cdi, &last_written))
857 cd->capacity = max_t(long, cd->capacity, last_written);
858
859 sector_size = get_unaligned_be32(&buffer[4]);
860 switch (sector_size) {
861 /*
862 * HP 4020i CD-Recorder reports 2340 byte sectors
863 * Philips CD-Writers report 2352 byte sectors
864 *
865 * Use 2k sectors for them..
866 */
867 case 0:
868 case 2340:
869 case 2352:
870 sector_size = 2048;
871 fallthrough;
872 case 2048:
873 cd->capacity *= 4;
874 fallthrough;
875 case 512:
876 break;
877 default:
878 sr_printk(KERN_INFO, cd,
879 "unsupported sector size %d.", sector_size);
880 cd->capacity = 0;
881 }
882
883 cd->device->sector_size = sector_size;
884
885 /*
886 * Add this so that we have the ability to correctly gauge
887 * what the device is capable of.
888 */
889 set_capacity(cd->disk, cd->capacity);
890 }
891
892 queue = cd->device->request_queue;
893 blk_queue_logical_block_size(queue, sector_size);
894
895 return;
896 }
897
get_capabilities(struct scsi_cd * cd)898 static void get_capabilities(struct scsi_cd *cd)
899 {
900 unsigned char *buffer;
901 struct scsi_mode_data data;
902 struct scsi_sense_hdr sshdr;
903 unsigned int ms_len = 128;
904 int rc, n;
905
906 static const char *loadmech[] =
907 {
908 "caddy",
909 "tray",
910 "pop-up",
911 "",
912 "changer",
913 "cartridge changer",
914 "",
915 ""
916 };
917
918
919 /* allocate transfer buffer */
920 buffer = kmalloc(512, GFP_KERNEL);
921 if (!buffer) {
922 sr_printk(KERN_ERR, cd, "out of memory.\n");
923 return;
924 }
925
926 /* eat unit attentions */
927 scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
928
929 /* ask for mode page 0x2a */
930 rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
931 SR_TIMEOUT, 3, &data, NULL);
932
933 if (rc < 0 || data.length > ms_len ||
934 data.header_length + data.block_descriptor_length > data.length) {
935 /* failed, drive doesn't have capabilities mode page */
936 cd->cdi.speed = 1;
937 cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
938 CDC_DVD | CDC_DVD_RAM |
939 CDC_SELECT_DISC | CDC_SELECT_SPEED |
940 CDC_MRW | CDC_MRW_W | CDC_RAM);
941 kfree(buffer);
942 sr_printk(KERN_INFO, cd, "scsi-1 drive");
943 return;
944 }
945
946 n = data.header_length + data.block_descriptor_length;
947 cd->cdi.speed = get_unaligned_be16(&buffer[n + 8]) / 176;
948 cd->readcd_known = 1;
949 cd->readcd_cdda = buffer[n + 5] & 0x01;
950 /* print some capability bits */
951 sr_printk(KERN_INFO, cd,
952 "scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n",
953 get_unaligned_be16(&buffer[n + 14]) / 176,
954 cd->cdi.speed,
955 buffer[n + 3] & 0x01 ? "writer " : "", /* CD Writer */
956 buffer[n + 3] & 0x20 ? "dvd-ram " : "",
957 buffer[n + 2] & 0x02 ? "cd/rw " : "", /* can read rewriteable */
958 buffer[n + 4] & 0x20 ? "xa/form2 " : "", /* can read xa/from2 */
959 buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
960 loadmech[buffer[n + 6] >> 5]);
961 if ((buffer[n + 6] >> 5) == 0)
962 /* caddy drives can't close tray... */
963 cd->cdi.mask |= CDC_CLOSE_TRAY;
964 if ((buffer[n + 2] & 0x8) == 0)
965 /* not a DVD drive */
966 cd->cdi.mask |= CDC_DVD;
967 if ((buffer[n + 3] & 0x20) == 0)
968 /* can't write DVD-RAM media */
969 cd->cdi.mask |= CDC_DVD_RAM;
970 if ((buffer[n + 3] & 0x10) == 0)
971 /* can't write DVD-R media */
972 cd->cdi.mask |= CDC_DVD_R;
973 if ((buffer[n + 3] & 0x2) == 0)
974 /* can't write CD-RW media */
975 cd->cdi.mask |= CDC_CD_RW;
976 if ((buffer[n + 3] & 0x1) == 0)
977 /* can't write CD-R media */
978 cd->cdi.mask |= CDC_CD_R;
979 if ((buffer[n + 6] & 0x8) == 0)
980 /* can't eject */
981 cd->cdi.mask |= CDC_OPEN_TRAY;
982
983 if ((buffer[n + 6] >> 5) == mechtype_individual_changer ||
984 (buffer[n + 6] >> 5) == mechtype_cartridge_changer)
985 cd->cdi.capacity =
986 cdrom_number_of_slots(&cd->cdi);
987 if (cd->cdi.capacity <= 1)
988 /* not a changer */
989 cd->cdi.mask |= CDC_SELECT_DISC;
990 /*else I don't think it can close its tray
991 cd->cdi.mask |= CDC_CLOSE_TRAY; */
992
993 /*
994 * if DVD-RAM, MRW-W or CD-RW, we are randomly writable
995 */
996 if ((cd->cdi.mask & (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) !=
997 (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) {
998 cd->writeable = 1;
999 }
1000
1001 kfree(buffer);
1002 }
1003
1004 /*
1005 * sr_packet() is the entry point for the generic commands generated
1006 * by the Uniform CD-ROM layer.
1007 */
sr_packet(struct cdrom_device_info * cdi,struct packet_command * cgc)1008 static int sr_packet(struct cdrom_device_info *cdi,
1009 struct packet_command *cgc)
1010 {
1011 struct scsi_cd *cd = cdi->handle;
1012 struct scsi_device *sdev = cd->device;
1013
1014 if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info)
1015 return -EDRIVE_CANT_DO_THIS;
1016
1017 if (cgc->timeout <= 0)
1018 cgc->timeout = IOCTL_TIMEOUT;
1019
1020 sr_do_ioctl(cd, cgc);
1021
1022 return cgc->stat;
1023 }
1024
1025 /**
1026 * sr_kref_release - Called to free the scsi_cd structure
1027 * @kref: pointer to embedded kref
1028 *
1029 * sr_ref_mutex must be held entering this routine. Because it is
1030 * called on last put, you should always use the scsi_cd_get()
1031 * scsi_cd_put() helpers which manipulate the semaphore directly
1032 * and never do a direct kref_put().
1033 **/
sr_kref_release(struct kref * kref)1034 static void sr_kref_release(struct kref *kref)
1035 {
1036 struct scsi_cd *cd = container_of(kref, struct scsi_cd, kref);
1037 struct gendisk *disk = cd->disk;
1038
1039 spin_lock(&sr_index_lock);
1040 clear_bit(MINOR(disk_devt(disk)), sr_index_bits);
1041 spin_unlock(&sr_index_lock);
1042
1043 unregister_cdrom(&cd->cdi);
1044
1045 disk->private_data = NULL;
1046
1047 put_disk(disk);
1048
1049 mutex_destroy(&cd->lock);
1050
1051 kfree(cd);
1052 }
1053
sr_remove(struct device * dev)1054 static int sr_remove(struct device *dev)
1055 {
1056 struct scsi_cd *cd = dev_get_drvdata(dev);
1057
1058 scsi_autopm_get_device(cd->device);
1059
1060 del_gendisk(cd->disk);
1061 dev_set_drvdata(dev, NULL);
1062
1063 mutex_lock(&sr_ref_mutex);
1064 kref_put(&cd->kref, sr_kref_release);
1065 mutex_unlock(&sr_ref_mutex);
1066
1067 return 0;
1068 }
1069
init_sr(void)1070 static int __init init_sr(void)
1071 {
1072 int rc;
1073
1074 rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
1075 if (rc)
1076 return rc;
1077 rc = scsi_register_driver(&sr_template.gendrv);
1078 if (rc)
1079 unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
1080
1081 return rc;
1082 }
1083
exit_sr(void)1084 static void __exit exit_sr(void)
1085 {
1086 scsi_unregister_driver(&sr_template.gendrv);
1087 unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
1088 }
1089
1090 module_init(init_sr);
1091 module_exit(exit_sr);
1092 MODULE_LICENSE("GPL");
1093