xref: /linux/drivers/scsi/sr.c (revision 8e3ed5440b0c305dcd1d5fa7419bd8066d22ef42)
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/major.h>
48 #include <linux/blkdev.h>
49 #include <linux/blk-pm.h>
50 #include <linux/mutex.h>
51 #include <linux/slab.h>
52 #include <linux/pm_runtime.h>
53 #include <linux/uaccess.h>
54 
55 #include <asm/unaligned.h>
56 
57 #include <scsi/scsi.h>
58 #include <scsi/scsi_dbg.h>
59 #include <scsi/scsi_device.h>
60 #include <scsi/scsi_driver.h>
61 #include <scsi/scsi_cmnd.h>
62 #include <scsi/scsi_eh.h>
63 #include <scsi/scsi_host.h>
64 #include <scsi/scsi_ioctl.h>	/* For the door lock/unlock commands */
65 
66 #include "scsi_logging.h"
67 #include "sr.h"
68 
69 
70 MODULE_DESCRIPTION("SCSI cdrom (sr) driver");
71 MODULE_LICENSE("GPL");
72 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR);
73 MODULE_ALIAS_SCSI_DEVICE(TYPE_ROM);
74 MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
75 
76 #define SR_DISKS	256
77 
78 #define SR_CAPABILITIES \
79 	(CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|CDC_SELECT_SPEED| \
80 	 CDC_SELECT_DISC|CDC_MULTI_SESSION|CDC_MCN|CDC_MEDIA_CHANGED| \
81 	 CDC_PLAY_AUDIO|CDC_RESET|CDC_DRIVE_STATUS| \
82 	 CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_DVD_RAM|CDC_GENERIC_PACKET| \
83 	 CDC_MRW|CDC_MRW_W|CDC_RAM)
84 
85 static int sr_probe(struct device *);
86 static int sr_remove(struct device *);
87 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt);
88 static int sr_done(struct scsi_cmnd *);
89 static int sr_runtime_suspend(struct device *dev);
90 
91 static const struct dev_pm_ops sr_pm_ops = {
92 	.runtime_suspend	= sr_runtime_suspend,
93 };
94 
95 static struct scsi_driver sr_template = {
96 	.gendrv = {
97 		.name   	= "sr",
98 		.owner		= THIS_MODULE,
99 		.probe		= sr_probe,
100 		.remove		= sr_remove,
101 		.pm		= &sr_pm_ops,
102 	},
103 	.init_command		= sr_init_command,
104 	.done			= sr_done,
105 };
106 
107 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
108 static DEFINE_SPINLOCK(sr_index_lock);
109 
110 static struct lock_class_key sr_bio_compl_lkclass;
111 
112 static int sr_open(struct cdrom_device_info *, int);
113 static void sr_release(struct cdrom_device_info *);
114 
115 static void get_sectorsize(struct scsi_cd *);
116 static int get_capabilities(struct scsi_cd *);
117 
118 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
119 				    unsigned int clearing, int slot);
120 static int sr_packet(struct cdrom_device_info *, struct packet_command *);
121 static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
122 		u32 lba, u32 nr, u8 *last_sense);
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 	.generic_packet		= sr_packet,
137 	.read_cdda_bpc		= sr_read_cdda_bpc,
138 	.capability		= SR_CAPABILITIES,
139 };
140 
141 static inline struct scsi_cd *scsi_cd(struct gendisk *disk)
142 {
143 	return disk->private_data;
144 }
145 
146 static int sr_runtime_suspend(struct device *dev)
147 {
148 	struct scsi_cd *cd = dev_get_drvdata(dev);
149 
150 	if (!cd)	/* E.g.: runtime suspend following sr_remove() */
151 		return 0;
152 
153 	if (cd->media_present)
154 		return -EBUSY;
155 	else
156 		return 0;
157 }
158 
159 static unsigned int sr_get_events(struct scsi_device *sdev)
160 {
161 	u8 buf[8];
162 	u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION,
163 		     1,			/* polled */
164 		     0, 0,		/* reserved */
165 		     1 << 4,		/* notification class: media */
166 		     0, 0,		/* reserved */
167 		     0, sizeof(buf),	/* allocation length */
168 		     0,			/* control */
169 	};
170 	struct event_header *eh = (void *)buf;
171 	struct media_event_desc *med = (void *)(buf + 4);
172 	struct scsi_sense_hdr sshdr;
173 	const struct scsi_exec_args exec_args = {
174 		.sshdr = &sshdr,
175 	};
176 	int result;
177 
178 	result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buf, sizeof(buf),
179 				  SR_TIMEOUT, MAX_RETRIES, &exec_args);
180 	if (result > 0 && scsi_sense_valid(&sshdr) &&
181 	    sshdr.sense_key == UNIT_ATTENTION)
182 		return DISK_EVENT_MEDIA_CHANGE;
183 
184 	if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
185 		return 0;
186 
187 	if (eh->nea || eh->notification_class != 0x4)
188 		return 0;
189 
190 	if (med->media_event_code == 1)
191 		return DISK_EVENT_EJECT_REQUEST;
192 	else if (med->media_event_code == 2)
193 		return DISK_EVENT_MEDIA_CHANGE;
194 	else if (med->media_event_code == 3)
195 		return DISK_EVENT_MEDIA_CHANGE;
196 	return 0;
197 }
198 
199 /*
200  * This function checks to see if the media has been changed or eject
201  * button has been pressed.  It is possible that we have already
202  * sensed a change, or the drive may have sensed one and not yet
203  * reported it.  The past events are accumulated in sdev->changed and
204  * returned together with the current state.
205  */
206 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
207 				    unsigned int clearing, int slot)
208 {
209 	struct scsi_cd *cd = cdi->handle;
210 	bool last_present;
211 	struct scsi_sense_hdr sshdr;
212 	unsigned int events;
213 	int ret;
214 
215 	/* no changer support */
216 	if (CDSL_CURRENT != slot)
217 		return 0;
218 
219 	events = sr_get_events(cd->device);
220 	cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE;
221 
222 	/*
223 	 * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree
224 	 * for several times in a row.  We rely on TUR only for this likely
225 	 * broken device, to prevent generating incorrect media changed
226 	 * events for every open().
227 	 */
228 	if (cd->ignore_get_event) {
229 		events &= ~DISK_EVENT_MEDIA_CHANGE;
230 		goto do_tur;
231 	}
232 
233 	/*
234 	 * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE
235 	 * is being cleared.  Note that there are devices which hang
236 	 * if asked to execute TUR repeatedly.
237 	 */
238 	if (cd->device->changed) {
239 		events |= DISK_EVENT_MEDIA_CHANGE;
240 		cd->device->changed = 0;
241 		cd->tur_changed = true;
242 	}
243 
244 	if (!(clearing & DISK_EVENT_MEDIA_CHANGE))
245 		return events;
246 do_tur:
247 	/* let's see whether the media is there with TUR */
248 	last_present = cd->media_present;
249 	ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
250 
251 	/*
252 	 * Media is considered to be present if TUR succeeds or fails with
253 	 * sense data indicating something other than media-not-present
254 	 * (ASC 0x3a).
255 	 */
256 	cd->media_present = scsi_status_is_good(ret) ||
257 		(scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a);
258 
259 	if (last_present != cd->media_present)
260 		cd->device->changed = 1;
261 
262 	if (cd->device->changed) {
263 		events |= DISK_EVENT_MEDIA_CHANGE;
264 		cd->device->changed = 0;
265 		cd->tur_changed = true;
266 	}
267 
268 	if (cd->ignore_get_event)
269 		return events;
270 
271 	/* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */
272 	if (!cd->tur_changed) {
273 		if (cd->get_event_changed) {
274 			if (cd->tur_mismatch++ > 8) {
275 				sr_printk(KERN_WARNING, cd,
276 					  "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n");
277 				cd->ignore_get_event = true;
278 			}
279 		} else {
280 			cd->tur_mismatch = 0;
281 		}
282 	}
283 	cd->tur_changed = false;
284 	cd->get_event_changed = false;
285 
286 	return events;
287 }
288 
289 /*
290  * sr_done is the interrupt routine for the device driver.
291  *
292  * It will be notified on the end of a SCSI read / write, and will take one
293  * of several actions based on success or failure.
294  */
295 static int sr_done(struct scsi_cmnd *SCpnt)
296 {
297 	int result = SCpnt->result;
298 	int this_count = scsi_bufflen(SCpnt);
299 	int good_bytes = (result == 0 ? this_count : 0);
300 	int block_sectors = 0;
301 	long error_sector;
302 	struct request *rq = scsi_cmd_to_rq(SCpnt);
303 	struct scsi_cd *cd = scsi_cd(rq->q->disk);
304 
305 #ifdef DEBUG
306 	scmd_printk(KERN_INFO, SCpnt, "done: %x\n", result);
307 #endif
308 
309 	/*
310 	 * Handle MEDIUM ERRORs or VOLUME OVERFLOWs that indicate partial
311 	 * success.  Since this is a relatively rare error condition, no
312 	 * care is taken to avoid unnecessary additional work such as
313 	 * memcpy's that could be avoided.
314 	 */
315 	if (scsi_status_is_check_condition(result) &&
316 	    (SCpnt->sense_buffer[0] & 0x7f) == 0x70) { /* Sense current */
317 		switch (SCpnt->sense_buffer[2]) {
318 		case MEDIUM_ERROR:
319 		case VOLUME_OVERFLOW:
320 		case ILLEGAL_REQUEST:
321 			if (!(SCpnt->sense_buffer[0] & 0x90))
322 				break;
323 			error_sector =
324 				get_unaligned_be32(&SCpnt->sense_buffer[3]);
325 			if (rq->bio != NULL)
326 				block_sectors = bio_sectors(rq->bio);
327 			if (block_sectors < 4)
328 				block_sectors = 4;
329 			if (cd->device->sector_size == 2048)
330 				error_sector <<= 2;
331 			error_sector &= ~(block_sectors - 1);
332 			good_bytes = (error_sector - blk_rq_pos(rq)) << 9;
333 			if (good_bytes < 0 || good_bytes >= this_count)
334 				good_bytes = 0;
335 			/*
336 			 * The SCSI specification allows for the value
337 			 * returned by READ CAPACITY to be up to 75 2K
338 			 * sectors past the last readable block.
339 			 * Therefore, if we hit a medium error within the
340 			 * last 75 2K sectors, we decrease the saved size
341 			 * value.
342 			 */
343 			if (error_sector < get_capacity(cd->disk) &&
344 			    cd->capacity - error_sector < 4 * 75)
345 				set_capacity(cd->disk, error_sector);
346 			break;
347 
348 		case RECOVERED_ERROR:
349 			good_bytes = this_count;
350 			break;
351 
352 		default:
353 			break;
354 		}
355 	}
356 
357 	return good_bytes;
358 }
359 
360 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
361 {
362 	int block = 0, this_count, s_size;
363 	struct scsi_cd *cd;
364 	struct request *rq = scsi_cmd_to_rq(SCpnt);
365 	blk_status_t ret;
366 
367 	ret = scsi_alloc_sgtables(SCpnt);
368 	if (ret != BLK_STS_OK)
369 		return ret;
370 	cd = scsi_cd(rq->q->disk);
371 
372 	SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
373 		"Doing sr request, block = %d\n", block));
374 
375 	if (!cd->device || !scsi_device_online(cd->device)) {
376 		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
377 			"Finishing %u sectors\n", blk_rq_sectors(rq)));
378 		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
379 			"Retry with 0x%p\n", SCpnt));
380 		goto out;
381 	}
382 
383 	if (cd->device->changed) {
384 		/*
385 		 * quietly refuse to do anything to a changed disc until the
386 		 * changed bit has been reset
387 		 */
388 		goto out;
389 	}
390 
391 	s_size = cd->device->sector_size;
392 	if (s_size != 512 && s_size != 1024 && s_size != 2048) {
393 		scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
394 		goto out;
395 	}
396 
397 	switch (req_op(rq)) {
398 	case REQ_OP_WRITE:
399 		if (!cd->writeable)
400 			goto out;
401 		SCpnt->cmnd[0] = WRITE_10;
402 		cd->cdi.media_written = 1;
403 		break;
404 	case REQ_OP_READ:
405 		SCpnt->cmnd[0] = READ_10;
406 		break;
407 	default:
408 		blk_dump_rq_flags(rq, "Unknown sr command");
409 		goto out;
410 	}
411 
412 	{
413 		struct scatterlist *sg;
414 		int i, size = 0, sg_count = scsi_sg_count(SCpnt);
415 
416 		scsi_for_each_sg(SCpnt, sg, sg_count, i)
417 			size += sg->length;
418 
419 		if (size != scsi_bufflen(SCpnt)) {
420 			scmd_printk(KERN_ERR, SCpnt,
421 				"mismatch count %d, bytes %d\n",
422 				size, scsi_bufflen(SCpnt));
423 			if (scsi_bufflen(SCpnt) > size)
424 				SCpnt->sdb.length = size;
425 		}
426 	}
427 
428 	/*
429 	 * request doesn't start on hw block boundary, add scatter pads
430 	 */
431 	if (((unsigned int)blk_rq_pos(rq) % (s_size >> 9)) ||
432 	    (scsi_bufflen(SCpnt) % s_size)) {
433 		scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
434 		goto out;
435 	}
436 
437 	this_count = (scsi_bufflen(SCpnt) >> 9) / (s_size >> 9);
438 
439 
440 	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
441 					"%s %d/%u 512 byte blocks.\n",
442 					(rq_data_dir(rq) == WRITE) ?
443 					"writing" : "reading",
444 					this_count, blk_rq_sectors(rq)));
445 
446 	SCpnt->cmnd[1] = 0;
447 	block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);
448 
449 	if (this_count > 0xffff) {
450 		this_count = 0xffff;
451 		SCpnt->sdb.length = this_count * s_size;
452 	}
453 
454 	put_unaligned_be32(block, &SCpnt->cmnd[2]);
455 	SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
456 	put_unaligned_be16(this_count, &SCpnt->cmnd[7]);
457 
458 	/*
459 	 * We shouldn't disconnect in the middle of a sector, so with a dumb
460 	 * host adapter, it's safe to assume that we can at least transfer
461 	 * this many bytes between each connect / disconnect.
462 	 */
463 	SCpnt->transfersize = cd->device->sector_size;
464 	SCpnt->underflow = this_count << 9;
465 	SCpnt->allowed = MAX_RETRIES;
466 	SCpnt->cmd_len = 10;
467 
468 	/*
469 	 * This indicates that the command is ready from our end to be queued.
470 	 */
471 	return BLK_STS_OK;
472  out:
473 	scsi_free_sgtables(SCpnt);
474 	return BLK_STS_IOERR;
475 }
476 
477 static void sr_revalidate_disk(struct scsi_cd *cd)
478 {
479 	struct scsi_sense_hdr sshdr;
480 
481 	/* if the unit is not ready, nothing more to do */
482 	if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr))
483 		return;
484 	sr_cd_check(&cd->cdi);
485 	get_sectorsize(cd);
486 }
487 
488 static int sr_block_open(struct gendisk *disk, blk_mode_t mode)
489 {
490 	struct scsi_cd *cd = scsi_cd(disk);
491 	struct scsi_device *sdev = cd->device;
492 	int ret;
493 
494 	if (scsi_device_get(cd->device))
495 		return -ENXIO;
496 
497 	scsi_autopm_get_device(sdev);
498 	if (disk_check_media_change(disk))
499 		sr_revalidate_disk(cd);
500 
501 	mutex_lock(&cd->lock);
502 	ret = cdrom_open(&cd->cdi, mode);
503 	mutex_unlock(&cd->lock);
504 
505 	scsi_autopm_put_device(sdev);
506 	if (ret)
507 		scsi_device_put(cd->device);
508 	return ret;
509 }
510 
511 static void sr_block_release(struct gendisk *disk)
512 {
513 	struct scsi_cd *cd = scsi_cd(disk);
514 
515 	mutex_lock(&cd->lock);
516 	cdrom_release(&cd->cdi);
517 	mutex_unlock(&cd->lock);
518 
519 	scsi_device_put(cd->device);
520 }
521 
522 static int sr_block_ioctl(struct block_device *bdev, blk_mode_t mode,
523 		unsigned cmd, unsigned long arg)
524 {
525 	struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
526 	struct scsi_device *sdev = cd->device;
527 	void __user *argp = (void __user *)arg;
528 	int ret;
529 
530 	if (bdev_is_partition(bdev) && !capable(CAP_SYS_RAWIO))
531 		return -ENOIOCTLCMD;
532 
533 	mutex_lock(&cd->lock);
534 
535 	ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
536 			(mode & BLK_OPEN_NDELAY));
537 	if (ret)
538 		goto out;
539 
540 	scsi_autopm_get_device(sdev);
541 
542 	if (cmd != CDROMCLOSETRAY && cmd != CDROMEJECT) {
543 		ret = cdrom_ioctl(&cd->cdi, bdev, cmd, arg);
544 		if (ret != -ENOSYS)
545 			goto put;
546 	}
547 	ret = scsi_ioctl(sdev, mode & BLK_OPEN_WRITE, cmd, argp);
548 
549 put:
550 	scsi_autopm_put_device(sdev);
551 out:
552 	mutex_unlock(&cd->lock);
553 	return ret;
554 }
555 
556 static unsigned int sr_block_check_events(struct gendisk *disk,
557 					  unsigned int clearing)
558 {
559 	struct scsi_cd *cd = disk->private_data;
560 
561 	if (atomic_read(&cd->device->disk_events_disable_depth))
562 		return 0;
563 	return cdrom_check_events(&cd->cdi, clearing);
564 }
565 
566 static void sr_free_disk(struct gendisk *disk)
567 {
568 	struct scsi_cd *cd = disk->private_data;
569 
570 	spin_lock(&sr_index_lock);
571 	clear_bit(MINOR(disk_devt(disk)), sr_index_bits);
572 	spin_unlock(&sr_index_lock);
573 
574 	unregister_cdrom(&cd->cdi);
575 	mutex_destroy(&cd->lock);
576 	kfree(cd);
577 }
578 
579 static const struct block_device_operations sr_bdops =
580 {
581 	.owner		= THIS_MODULE,
582 	.open		= sr_block_open,
583 	.release	= sr_block_release,
584 	.ioctl		= sr_block_ioctl,
585 	.compat_ioctl	= blkdev_compat_ptr_ioctl,
586 	.check_events	= sr_block_check_events,
587 	.free_disk	= sr_free_disk,
588 };
589 
590 static int sr_open(struct cdrom_device_info *cdi, int purpose)
591 {
592 	struct scsi_cd *cd = cdi->handle;
593 	struct scsi_device *sdev = cd->device;
594 
595 	/*
596 	 * If the device is in error recovery, wait until it is done.
597 	 * If the device is offline, then disallow any access to it.
598 	 */
599 	if (!scsi_block_when_processing_errors(sdev))
600 		return -ENXIO;
601 
602 	return 0;
603 }
604 
605 static void sr_release(struct cdrom_device_info *cdi)
606 {
607 }
608 
609 static int sr_probe(struct device *dev)
610 {
611 	struct scsi_device *sdev = to_scsi_device(dev);
612 	struct gendisk *disk;
613 	struct scsi_cd *cd;
614 	int minor, error;
615 
616 	scsi_autopm_get_device(sdev);
617 	error = -ENODEV;
618 	if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)
619 		goto fail;
620 
621 	error = -ENOMEM;
622 	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
623 	if (!cd)
624 		goto fail;
625 
626 	disk = blk_mq_alloc_disk_for_queue(sdev->request_queue,
627 					   &sr_bio_compl_lkclass);
628 	if (!disk)
629 		goto fail_free;
630 	mutex_init(&cd->lock);
631 
632 	spin_lock(&sr_index_lock);
633 	minor = find_first_zero_bit(sr_index_bits, SR_DISKS);
634 	if (minor == SR_DISKS) {
635 		spin_unlock(&sr_index_lock);
636 		error = -EBUSY;
637 		goto fail_put;
638 	}
639 	__set_bit(minor, sr_index_bits);
640 	spin_unlock(&sr_index_lock);
641 
642 	disk->major = SCSI_CDROM_MAJOR;
643 	disk->first_minor = minor;
644 	disk->minors = 1;
645 	sprintf(disk->disk_name, "sr%d", minor);
646 	disk->fops = &sr_bdops;
647 	disk->flags |= GENHD_FL_REMOVABLE | GENHD_FL_NO_PART;
648 	disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST;
649 	disk->event_flags = DISK_EVENT_FLAG_POLL | DISK_EVENT_FLAG_UEVENT |
650 				DISK_EVENT_FLAG_BLOCK_ON_EXCL_WRITE;
651 
652 	blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
653 
654 	cd->device = sdev;
655 	cd->disk = disk;
656 	cd->capacity = 0x1fffff;
657 	cd->device->changed = 1;	/* force recheck CD type */
658 	cd->media_present = 1;
659 	cd->use = 1;
660 	cd->readcd_known = 0;
661 	cd->readcd_cdda = 0;
662 
663 	cd->cdi.ops = &sr_dops;
664 	cd->cdi.handle = cd;
665 	cd->cdi.mask = 0;
666 	cd->cdi.capacity = 1;
667 	sprintf(cd->cdi.name, "sr%d", minor);
668 
669 	sdev->sector_size = 2048;	/* A guess, just in case */
670 
671 	error = -ENOMEM;
672 	if (get_capabilities(cd))
673 		goto fail_minor;
674 	sr_vendor_init(cd);
675 
676 	set_capacity(disk, cd->capacity);
677 	disk->private_data = cd;
678 
679 	if (register_cdrom(disk, &cd->cdi))
680 		goto fail_minor;
681 
682 	/*
683 	 * Initialize block layer runtime PM stuffs before the
684 	 * periodic event checking request gets started in add_disk.
685 	 */
686 	blk_pm_runtime_init(sdev->request_queue, dev);
687 
688 	dev_set_drvdata(dev, cd);
689 	sr_revalidate_disk(cd);
690 
691 	error = device_add_disk(&sdev->sdev_gendev, disk, NULL);
692 	if (error)
693 		goto unregister_cdrom;
694 
695 	sdev_printk(KERN_DEBUG, sdev,
696 		    "Attached scsi CD-ROM %s\n", cd->cdi.name);
697 	scsi_autopm_put_device(cd->device);
698 
699 	return 0;
700 
701 unregister_cdrom:
702 	unregister_cdrom(&cd->cdi);
703 fail_minor:
704 	spin_lock(&sr_index_lock);
705 	clear_bit(minor, sr_index_bits);
706 	spin_unlock(&sr_index_lock);
707 fail_put:
708 	put_disk(disk);
709 	mutex_destroy(&cd->lock);
710 fail_free:
711 	kfree(cd);
712 fail:
713 	scsi_autopm_put_device(sdev);
714 	return error;
715 }
716 
717 
718 static void get_sectorsize(struct scsi_cd *cd)
719 {
720 	unsigned char cmd[10];
721 	unsigned char buffer[8];
722 	int the_result, retries = 3;
723 	int sector_size;
724 	struct request_queue *queue;
725 
726 	do {
727 		cmd[0] = READ_CAPACITY;
728 		memset((void *) &cmd[1], 0, 9);
729 		memset(buffer, 0, sizeof(buffer));
730 
731 		/* Do the command and wait.. */
732 		the_result = scsi_execute_cmd(cd->device, cmd, REQ_OP_DRV_IN,
733 					      buffer, sizeof(buffer),
734 					      SR_TIMEOUT, MAX_RETRIES, NULL);
735 
736 		retries--;
737 
738 	} while (the_result && retries);
739 
740 
741 	if (the_result) {
742 		cd->capacity = 0x1fffff;
743 		sector_size = 2048;	/* A guess, just in case */
744 	} else {
745 		long last_written;
746 
747 		cd->capacity = 1 + get_unaligned_be32(&buffer[0]);
748 		/*
749 		 * READ_CAPACITY doesn't return the correct size on
750 		 * certain UDF media.  If last_written is larger, use
751 		 * it instead.
752 		 *
753 		 * http://bugzilla.kernel.org/show_bug.cgi?id=9668
754 		 */
755 		if (!cdrom_get_last_written(&cd->cdi, &last_written))
756 			cd->capacity = max_t(long, cd->capacity, last_written);
757 
758 		sector_size = get_unaligned_be32(&buffer[4]);
759 		switch (sector_size) {
760 			/*
761 			 * HP 4020i CD-Recorder reports 2340 byte sectors
762 			 * Philips CD-Writers report 2352 byte sectors
763 			 *
764 			 * Use 2k sectors for them..
765 			 */
766 		case 0:
767 		case 2340:
768 		case 2352:
769 			sector_size = 2048;
770 			fallthrough;
771 		case 2048:
772 			cd->capacity *= 4;
773 			fallthrough;
774 		case 512:
775 			break;
776 		default:
777 			sr_printk(KERN_INFO, cd,
778 				  "unsupported sector size %d.", sector_size);
779 			cd->capacity = 0;
780 		}
781 
782 		cd->device->sector_size = sector_size;
783 
784 		/*
785 		 * Add this so that we have the ability to correctly gauge
786 		 * what the device is capable of.
787 		 */
788 		set_capacity(cd->disk, cd->capacity);
789 	}
790 
791 	queue = cd->device->request_queue;
792 	blk_queue_logical_block_size(queue, sector_size);
793 
794 	return;
795 }
796 
797 static int get_capabilities(struct scsi_cd *cd)
798 {
799 	unsigned char *buffer;
800 	struct scsi_mode_data data;
801 	struct scsi_sense_hdr sshdr;
802 	unsigned int ms_len = 128;
803 	int rc, n;
804 
805 	static const char *loadmech[] =
806 	{
807 		"caddy",
808 		"tray",
809 		"pop-up",
810 		"",
811 		"changer",
812 		"cartridge changer",
813 		"",
814 		""
815 	};
816 
817 
818 	/* allocate transfer buffer */
819 	buffer = kmalloc(512, GFP_KERNEL);
820 	if (!buffer) {
821 		sr_printk(KERN_ERR, cd, "out of memory.\n");
822 		return -ENOMEM;
823 	}
824 
825 	/* eat unit attentions */
826 	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
827 
828 	/* ask for mode page 0x2a */
829 	rc = scsi_mode_sense(cd->device, 0, 0x2a, 0, buffer, ms_len,
830 			     SR_TIMEOUT, 3, &data, NULL);
831 
832 	if (rc < 0 || data.length > ms_len ||
833 	    data.header_length + data.block_descriptor_length > data.length) {
834 		/* failed, drive doesn't have capabilities mode page */
835 		cd->cdi.speed = 1;
836 		cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
837 				 CDC_DVD | CDC_DVD_RAM |
838 				 CDC_SELECT_DISC | CDC_SELECT_SPEED |
839 				 CDC_MRW | CDC_MRW_W | CDC_RAM);
840 		kfree(buffer);
841 		sr_printk(KERN_INFO, cd, "scsi-1 drive");
842 		return 0;
843 	}
844 
845 	n = data.header_length + data.block_descriptor_length;
846 	cd->cdi.speed = get_unaligned_be16(&buffer[n + 8]) / 176;
847 	cd->readcd_known = 1;
848 	cd->readcd_cdda = buffer[n + 5] & 0x01;
849 	/* print some capability bits */
850 	sr_printk(KERN_INFO, cd,
851 		  "scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n",
852 		  get_unaligned_be16(&buffer[n + 14]) / 176,
853 		  cd->cdi.speed,
854 		  buffer[n + 3] & 0x01 ? "writer " : "", /* CD Writer */
855 		  buffer[n + 3] & 0x20 ? "dvd-ram " : "",
856 		  buffer[n + 2] & 0x02 ? "cd/rw " : "", /* can read rewriteable */
857 		  buffer[n + 4] & 0x20 ? "xa/form2 " : "",	/* can read xa/from2 */
858 		  buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
859 		  loadmech[buffer[n + 6] >> 5]);
860 	if ((buffer[n + 6] >> 5) == 0)
861 		/* caddy drives can't close tray... */
862 		cd->cdi.mask |= CDC_CLOSE_TRAY;
863 	if ((buffer[n + 2] & 0x8) == 0)
864 		/* not a DVD drive */
865 		cd->cdi.mask |= CDC_DVD;
866 	if ((buffer[n + 3] & 0x20) == 0)
867 		/* can't write DVD-RAM media */
868 		cd->cdi.mask |= CDC_DVD_RAM;
869 	if ((buffer[n + 3] & 0x10) == 0)
870 		/* can't write DVD-R media */
871 		cd->cdi.mask |= CDC_DVD_R;
872 	if ((buffer[n + 3] & 0x2) == 0)
873 		/* can't write CD-RW media */
874 		cd->cdi.mask |= CDC_CD_RW;
875 	if ((buffer[n + 3] & 0x1) == 0)
876 		/* can't write CD-R media */
877 		cd->cdi.mask |= CDC_CD_R;
878 	if ((buffer[n + 6] & 0x8) == 0)
879 		/* can't eject */
880 		cd->cdi.mask |= CDC_OPEN_TRAY;
881 
882 	if ((buffer[n + 6] >> 5) == mechtype_individual_changer ||
883 	    (buffer[n + 6] >> 5) == mechtype_cartridge_changer)
884 		cd->cdi.capacity =
885 		    cdrom_number_of_slots(&cd->cdi);
886 	if (cd->cdi.capacity <= 1)
887 		/* not a changer */
888 		cd->cdi.mask |= CDC_SELECT_DISC;
889 	/*else    I don't think it can close its tray
890 		cd->cdi.mask |= CDC_CLOSE_TRAY; */
891 
892 	/*
893 	 * if DVD-RAM, MRW-W or CD-RW, we are randomly writable
894 	 */
895 	if ((cd->cdi.mask & (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) !=
896 			(CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) {
897 		cd->writeable = 1;
898 	}
899 
900 	kfree(buffer);
901 	return 0;
902 }
903 
904 /*
905  * sr_packet() is the entry point for the generic commands generated
906  * by the Uniform CD-ROM layer.
907  */
908 static int sr_packet(struct cdrom_device_info *cdi,
909 		struct packet_command *cgc)
910 {
911 	struct scsi_cd *cd = cdi->handle;
912 	struct scsi_device *sdev = cd->device;
913 
914 	if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info)
915 		return -EDRIVE_CANT_DO_THIS;
916 
917 	if (cgc->timeout <= 0)
918 		cgc->timeout = IOCTL_TIMEOUT;
919 
920 	sr_do_ioctl(cd, cgc);
921 
922 	return cgc->stat;
923 }
924 
925 static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
926 		u32 lba, u32 nr, u8 *last_sense)
927 {
928 	struct gendisk *disk = cdi->disk;
929 	u32 len = nr * CD_FRAMESIZE_RAW;
930 	struct scsi_cmnd *scmd;
931 	struct request *rq;
932 	struct bio *bio;
933 	int ret;
934 
935 	rq = scsi_alloc_request(disk->queue, REQ_OP_DRV_IN, 0);
936 	if (IS_ERR(rq))
937 		return PTR_ERR(rq);
938 	scmd = blk_mq_rq_to_pdu(rq);
939 
940 	ret = blk_rq_map_user(disk->queue, rq, NULL, ubuf, len, GFP_KERNEL);
941 	if (ret)
942 		goto out_put_request;
943 
944 	scmd->cmnd[0] = GPCMD_READ_CD;
945 	scmd->cmnd[1] = 1 << 2;
946 	scmd->cmnd[2] = (lba >> 24) & 0xff;
947 	scmd->cmnd[3] = (lba >> 16) & 0xff;
948 	scmd->cmnd[4] = (lba >>  8) & 0xff;
949 	scmd->cmnd[5] = lba & 0xff;
950 	scmd->cmnd[6] = (nr >> 16) & 0xff;
951 	scmd->cmnd[7] = (nr >>  8) & 0xff;
952 	scmd->cmnd[8] = nr & 0xff;
953 	scmd->cmnd[9] = 0xf8;
954 	scmd->cmd_len = 12;
955 	rq->timeout = 60 * HZ;
956 	bio = rq->bio;
957 
958 	blk_execute_rq(rq, false);
959 	if (scmd->result) {
960 		struct scsi_sense_hdr sshdr;
961 
962 		scsi_normalize_sense(scmd->sense_buffer, scmd->sense_len,
963 				     &sshdr);
964 		*last_sense = sshdr.sense_key;
965 		ret = -EIO;
966 	}
967 
968 	if (blk_rq_unmap_user(bio))
969 		ret = -EFAULT;
970 out_put_request:
971 	blk_mq_free_request(rq);
972 	return ret;
973 }
974 
975 static int sr_remove(struct device *dev)
976 {
977 	struct scsi_cd *cd = dev_get_drvdata(dev);
978 
979 	scsi_autopm_get_device(cd->device);
980 
981 	del_gendisk(cd->disk);
982 	put_disk(cd->disk);
983 
984 	return 0;
985 }
986 
987 static int __init init_sr(void)
988 {
989 	int rc;
990 
991 	rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
992 	if (rc)
993 		return rc;
994 	rc = scsi_register_driver(&sr_template.gendrv);
995 	if (rc)
996 		unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
997 
998 	return rc;
999 }
1000 
1001 static void __exit exit_sr(void)
1002 {
1003 	scsi_unregister_driver(&sr_template.gendrv);
1004 	unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
1005 }
1006 
1007 module_init(init_sr);
1008 module_exit(exit_sr);
1009 MODULE_LICENSE("GPL");
1010