xref: /openbmc/linux/drivers/scsi/sr.c (revision 84764a41)
1 /*
2  *  sr.c Copyright (C) 1992 David Giller
3  *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
4  *
5  *  adapted from:
6  *      sd.c Copyright (C) 1992 Drew Eckhardt
7  *      Linux scsi disk driver by
8  *              Drew Eckhardt <drew@colorado.edu>
9  *
10  *	Modified by Eric Youngdale ericy@andante.org to
11  *	add scatter-gather, multiple outstanding request, and other
12  *	enhancements.
13  *
14  *      Modified by Eric Youngdale eric@andante.org to support loadable
15  *      low-level scsi drivers.
16  *
17  *      Modified by Thomas Quinot thomas@melchior.cuivre.fdn.fr to
18  *      provide auto-eject.
19  *
20  *      Modified by Gerd Knorr <kraxel@cs.tu-berlin.de> to support the
21  *      generic cdrom interface
22  *
23  *      Modified by Jens Axboe <axboe@suse.de> - Uniform sr_packet()
24  *      interface, capabilities probe additions, ioctl cleanups, etc.
25  *
26  *	Modified by Richard Gooch <rgooch@atnf.csiro.au> to support devfs
27  *
28  *	Modified by Jens Axboe <axboe@suse.de> - support DVD-RAM
29  *	transparently and lose the GHOST hack
30  *
31  *	Modified by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
32  *	check resource allocation in sr_init and some cleanups
33  */
34 
35 #include <linux/module.h>
36 #include <linux/fs.h>
37 #include <linux/kernel.h>
38 #include <linux/mm.h>
39 #include <linux/bio.h>
40 #include <linux/string.h>
41 #include <linux/errno.h>
42 #include <linux/cdrom.h>
43 #include <linux/interrupt.h>
44 #include <linux/init.h>
45 #include <linux/blkdev.h>
46 #include <linux/mutex.h>
47 #include <linux/slab.h>
48 #include <asm/uaccess.h>
49 
50 #include <scsi/scsi.h>
51 #include <scsi/scsi_dbg.h>
52 #include <scsi/scsi_device.h>
53 #include <scsi/scsi_driver.h>
54 #include <scsi/scsi_cmnd.h>
55 #include <scsi/scsi_eh.h>
56 #include <scsi/scsi_host.h>
57 #include <scsi/scsi_ioctl.h>	/* For the door lock/unlock commands */
58 
59 #include "scsi_logging.h"
60 #include "sr.h"
61 
62 
63 MODULE_DESCRIPTION("SCSI cdrom (sr) driver");
64 MODULE_LICENSE("GPL");
65 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR);
66 MODULE_ALIAS_SCSI_DEVICE(TYPE_ROM);
67 MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
68 
69 #define SR_DISKS	256
70 
71 #define SR_CAPABILITIES \
72 	(CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|CDC_SELECT_SPEED| \
73 	 CDC_SELECT_DISC|CDC_MULTI_SESSION|CDC_MCN|CDC_MEDIA_CHANGED| \
74 	 CDC_PLAY_AUDIO|CDC_RESET|CDC_DRIVE_STATUS| \
75 	 CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_DVD_RAM|CDC_GENERIC_PACKET| \
76 	 CDC_MRW|CDC_MRW_W|CDC_RAM)
77 
78 static DEFINE_MUTEX(sr_mutex);
79 static int sr_probe(struct device *);
80 static int sr_remove(struct device *);
81 static int sr_done(struct scsi_cmnd *);
82 
83 static struct scsi_driver sr_template = {
84 	.owner			= THIS_MODULE,
85 	.gendrv = {
86 		.name   	= "sr",
87 		.probe		= sr_probe,
88 		.remove		= sr_remove,
89 	},
90 	.done			= sr_done,
91 };
92 
93 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
94 static DEFINE_SPINLOCK(sr_index_lock);
95 
96 /* This semaphore is used to mediate the 0->1 reference get in the
97  * face of object destruction (i.e. we can't allow a get on an
98  * object after last put) */
99 static DEFINE_MUTEX(sr_ref_mutex);
100 
101 static int sr_open(struct cdrom_device_info *, int);
102 static void sr_release(struct cdrom_device_info *);
103 
104 static void get_sectorsize(struct scsi_cd *);
105 static void get_capabilities(struct scsi_cd *);
106 
107 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
108 				    unsigned int clearing, int slot);
109 static int sr_packet(struct cdrom_device_info *, struct packet_command *);
110 
111 static struct cdrom_device_ops sr_dops = {
112 	.open			= sr_open,
113 	.release	 	= sr_release,
114 	.drive_status	 	= sr_drive_status,
115 	.check_events		= sr_check_events,
116 	.tray_move		= sr_tray_move,
117 	.lock_door		= sr_lock_door,
118 	.select_speed		= sr_select_speed,
119 	.get_last_session	= sr_get_last_session,
120 	.get_mcn		= sr_get_mcn,
121 	.reset			= sr_reset,
122 	.audio_ioctl		= sr_audio_ioctl,
123 	.capability		= SR_CAPABILITIES,
124 	.generic_packet		= sr_packet,
125 };
126 
127 static void sr_kref_release(struct kref *kref);
128 
129 static inline struct scsi_cd *scsi_cd(struct gendisk *disk)
130 {
131 	return container_of(disk->private_data, struct scsi_cd, driver);
132 }
133 
134 /*
135  * The get and put routines for the struct scsi_cd.  Note this entity
136  * has a scsi_device pointer and owns a reference to this.
137  */
138 static inline struct scsi_cd *scsi_cd_get(struct gendisk *disk)
139 {
140 	struct scsi_cd *cd = NULL;
141 
142 	mutex_lock(&sr_ref_mutex);
143 	if (disk->private_data == NULL)
144 		goto out;
145 	cd = scsi_cd(disk);
146 	kref_get(&cd->kref);
147 	if (scsi_device_get(cd->device))
148 		goto out_put;
149 	goto out;
150 
151  out_put:
152 	kref_put(&cd->kref, sr_kref_release);
153 	cd = NULL;
154  out:
155 	mutex_unlock(&sr_ref_mutex);
156 	return cd;
157 }
158 
159 static void scsi_cd_put(struct scsi_cd *cd)
160 {
161 	struct scsi_device *sdev = cd->device;
162 
163 	mutex_lock(&sr_ref_mutex);
164 	kref_put(&cd->kref, sr_kref_release);
165 	scsi_device_put(sdev);
166 	mutex_unlock(&sr_ref_mutex);
167 }
168 
169 static unsigned int sr_get_events(struct scsi_device *sdev)
170 {
171 	u8 buf[8];
172 	u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION,
173 		     1,			/* polled */
174 		     0, 0,		/* reserved */
175 		     1 << 4,		/* notification class: media */
176 		     0, 0,		/* reserved */
177 		     0, sizeof(buf),	/* allocation length */
178 		     0,			/* control */
179 	};
180 	struct event_header *eh = (void *)buf;
181 	struct media_event_desc *med = (void *)(buf + 4);
182 	struct scsi_sense_hdr sshdr;
183 	int result;
184 
185 	result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf),
186 				  &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL);
187 	if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
188 		return DISK_EVENT_MEDIA_CHANGE;
189 
190 	if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
191 		return 0;
192 
193 	if (eh->nea || eh->notification_class != 0x4)
194 		return 0;
195 
196 	if (med->media_event_code == 1)
197 		return DISK_EVENT_EJECT_REQUEST;
198 	else if (med->media_event_code == 2)
199 		return DISK_EVENT_MEDIA_CHANGE;
200 	return 0;
201 }
202 
203 /*
204  * This function checks to see if the media has been changed or eject
205  * button has been pressed.  It is possible that we have already
206  * sensed a change, or the drive may have sensed one and not yet
207  * reported it.  The past events are accumulated in sdev->changed and
208  * returned together with the current state.
209  */
210 static unsigned int sr_check_events(struct cdrom_device_info *cdi,
211 				    unsigned int clearing, int slot)
212 {
213 	struct scsi_cd *cd = cdi->handle;
214 	bool last_present;
215 	struct scsi_sense_hdr sshdr;
216 	unsigned int events;
217 	int ret;
218 
219 	/* no changer support */
220 	if (CDSL_CURRENT != slot)
221 		return 0;
222 
223 	events = sr_get_events(cd->device);
224 	cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE;
225 
226 	/*
227 	 * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree
228 	 * for several times in a row.  We rely on TUR only for this likely
229 	 * broken device, to prevent generating incorrect media changed
230 	 * events for every open().
231 	 */
232 	if (cd->ignore_get_event) {
233 		events &= ~DISK_EVENT_MEDIA_CHANGE;
234 		goto do_tur;
235 	}
236 
237 	/*
238 	 * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE
239 	 * is being cleared.  Note that there are devices which hang
240 	 * if asked to execute TUR repeatedly.
241 	 */
242 	if (cd->device->changed) {
243 		events |= DISK_EVENT_MEDIA_CHANGE;
244 		cd->device->changed = 0;
245 		cd->tur_changed = true;
246 	}
247 
248 	if (!(clearing & DISK_EVENT_MEDIA_CHANGE))
249 		return events;
250 do_tur:
251 	/* let's see whether the media is there with TUR */
252 	last_present = cd->media_present;
253 	ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
254 
255 	/*
256 	 * Media is considered to be present if TUR succeeds or fails with
257 	 * sense data indicating something other than media-not-present
258 	 * (ASC 0x3a).
259 	 */
260 	cd->media_present = scsi_status_is_good(ret) ||
261 		(scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a);
262 
263 	if (last_present != cd->media_present)
264 		cd->device->changed = 1;
265 
266 	if (cd->device->changed) {
267 		events |= DISK_EVENT_MEDIA_CHANGE;
268 		cd->device->changed = 0;
269 		cd->tur_changed = true;
270 	}
271 
272 	if (cd->ignore_get_event)
273 		return events;
274 
275 	/* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */
276 	if (!cd->tur_changed) {
277 		if (cd->get_event_changed) {
278 			if (cd->tur_mismatch++ > 8) {
279 				sdev_printk(KERN_WARNING, cd->device,
280 					    "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n");
281 				cd->ignore_get_event = true;
282 			}
283 		} else {
284 			cd->tur_mismatch = 0;
285 		}
286 	}
287 	cd->tur_changed = false;
288 	cd->get_event_changed = false;
289 
290 	return events;
291 }
292 
293 /*
294  * sr_done is the interrupt routine for the device driver.
295  *
296  * It will be notified on the end of a SCSI read / write, and will take one
297  * of several actions based on success or failure.
298  */
299 static int sr_done(struct scsi_cmnd *SCpnt)
300 {
301 	int result = SCpnt->result;
302 	int this_count = scsi_bufflen(SCpnt);
303 	int good_bytes = (result == 0 ? this_count : 0);
304 	int block_sectors = 0;
305 	long error_sector;
306 	struct scsi_cd *cd = scsi_cd(SCpnt->request->rq_disk);
307 
308 #ifdef DEBUG
309 	printk("sr.c done: %x\n", result);
310 #endif
311 
312 	/*
313 	 * Handle MEDIUM ERRORs or VOLUME OVERFLOWs that indicate partial
314 	 * success.  Since this is a relatively rare error condition, no
315 	 * care is taken to avoid unnecessary additional work such as
316 	 * memcpy's that could be avoided.
317 	 */
318 	if (driver_byte(result) != 0 &&		/* An error occurred */
319 	    (SCpnt->sense_buffer[0] & 0x7f) == 0x70) { /* Sense current */
320 		switch (SCpnt->sense_buffer[2]) {
321 		case MEDIUM_ERROR:
322 		case VOLUME_OVERFLOW:
323 		case ILLEGAL_REQUEST:
324 			if (!(SCpnt->sense_buffer[0] & 0x90))
325 				break;
326 			error_sector = (SCpnt->sense_buffer[3] << 24) |
327 				(SCpnt->sense_buffer[4] << 16) |
328 				(SCpnt->sense_buffer[5] << 8) |
329 				SCpnt->sense_buffer[6];
330 			if (SCpnt->request->bio != NULL)
331 				block_sectors =
332 					bio_sectors(SCpnt->request->bio);
333 			if (block_sectors < 4)
334 				block_sectors = 4;
335 			if (cd->device->sector_size == 2048)
336 				error_sector <<= 2;
337 			error_sector &= ~(block_sectors - 1);
338 			good_bytes = (error_sector -
339 				      blk_rq_pos(SCpnt->request)) << 9;
340 			if (good_bytes < 0 || good_bytes >= this_count)
341 				good_bytes = 0;
342 			/*
343 			 * The SCSI specification allows for the value
344 			 * returned by READ CAPACITY to be up to 75 2K
345 			 * sectors past the last readable block.
346 			 * Therefore, if we hit a medium error within the
347 			 * last 75 2K sectors, we decrease the saved size
348 			 * value.
349 			 */
350 			if (error_sector < get_capacity(cd->disk) &&
351 			    cd->capacity - error_sector < 4 * 75)
352 				set_capacity(cd->disk, error_sector);
353 			break;
354 
355 		case RECOVERED_ERROR:
356 			good_bytes = this_count;
357 			break;
358 
359 		default:
360 			break;
361 		}
362 	}
363 
364 	return good_bytes;
365 }
366 
367 static int sr_prep_fn(struct request_queue *q, struct request *rq)
368 {
369 	int block = 0, this_count, s_size;
370 	struct scsi_cd *cd;
371 	struct scsi_cmnd *SCpnt;
372 	struct scsi_device *sdp = q->queuedata;
373 	int ret;
374 
375 	if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
376 		ret = scsi_setup_blk_pc_cmnd(sdp, rq);
377 		goto out;
378 	} else if (rq->cmd_type != REQ_TYPE_FS) {
379 		ret = BLKPREP_KILL;
380 		goto out;
381 	}
382 	ret = scsi_setup_fs_cmnd(sdp, rq);
383 	if (ret != BLKPREP_OK)
384 		goto out;
385 	SCpnt = rq->special;
386 	cd = scsi_cd(rq->rq_disk);
387 
388 	/* from here on until we're complete, any goto out
389 	 * is used for a killable error condition */
390 	ret = BLKPREP_KILL;
391 
392 	SCSI_LOG_HLQUEUE(1, printk("Doing sr request, dev = %s, block = %d\n",
393 				cd->disk->disk_name, block));
394 
395 	if (!cd->device || !scsi_device_online(cd->device)) {
396 		SCSI_LOG_HLQUEUE(2, printk("Finishing %u sectors\n",
397 					   blk_rq_sectors(rq)));
398 		SCSI_LOG_HLQUEUE(2, printk("Retry with 0x%p\n", SCpnt));
399 		goto out;
400 	}
401 
402 	if (cd->device->changed) {
403 		/*
404 		 * quietly refuse to do anything to a changed disc until the
405 		 * changed bit has been reset
406 		 */
407 		goto out;
408 	}
409 
410 	/*
411 	 * we do lazy blocksize switching (when reading XA sectors,
412 	 * see CDROMREADMODE2 ioctl)
413 	 */
414 	s_size = cd->device->sector_size;
415 	if (s_size > 2048) {
416 		if (!in_interrupt())
417 			sr_set_blocklength(cd, 2048);
418 		else
419 			printk("sr: can't switch blocksize: in interrupt\n");
420 	}
421 
422 	if (s_size != 512 && s_size != 1024 && s_size != 2048) {
423 		scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
424 		goto out;
425 	}
426 
427 	if (rq_data_dir(rq) == WRITE) {
428 		if (!cd->device->writeable)
429 			goto out;
430 		SCpnt->cmnd[0] = WRITE_10;
431 		SCpnt->sc_data_direction = DMA_TO_DEVICE;
432  	 	cd->cdi.media_written = 1;
433 	} else if (rq_data_dir(rq) == READ) {
434 		SCpnt->cmnd[0] = READ_10;
435 		SCpnt->sc_data_direction = DMA_FROM_DEVICE;
436 	} else {
437 		blk_dump_rq_flags(rq, "Unknown sr command");
438 		goto out;
439 	}
440 
441 	{
442 		struct scatterlist *sg;
443 		int i, size = 0, sg_count = scsi_sg_count(SCpnt);
444 
445 		scsi_for_each_sg(SCpnt, sg, sg_count, i)
446 			size += sg->length;
447 
448 		if (size != scsi_bufflen(SCpnt)) {
449 			scmd_printk(KERN_ERR, SCpnt,
450 				"mismatch count %d, bytes %d\n",
451 				size, scsi_bufflen(SCpnt));
452 			if (scsi_bufflen(SCpnt) > size)
453 				SCpnt->sdb.length = size;
454 		}
455 	}
456 
457 	/*
458 	 * request doesn't start on hw block boundary, add scatter pads
459 	 */
460 	if (((unsigned int)blk_rq_pos(rq) % (s_size >> 9)) ||
461 	    (scsi_bufflen(SCpnt) % s_size)) {
462 		scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
463 		goto out;
464 	}
465 
466 	this_count = (scsi_bufflen(SCpnt) >> 9) / (s_size >> 9);
467 
468 
469 	SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%u 512 byte blocks.\n",
470 				cd->cdi.name,
471 				(rq_data_dir(rq) == WRITE) ?
472 					"writing" : "reading",
473 				this_count, blk_rq_sectors(rq)));
474 
475 	SCpnt->cmnd[1] = 0;
476 	block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);
477 
478 	if (this_count > 0xffff) {
479 		this_count = 0xffff;
480 		SCpnt->sdb.length = this_count * s_size;
481 	}
482 
483 	SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
484 	SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
485 	SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
486 	SCpnt->cmnd[5] = (unsigned char) block & 0xff;
487 	SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
488 	SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
489 	SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
490 
491 	/*
492 	 * We shouldn't disconnect in the middle of a sector, so with a dumb
493 	 * host adapter, it's safe to assume that we can at least transfer
494 	 * this many bytes between each connect / disconnect.
495 	 */
496 	SCpnt->transfersize = cd->device->sector_size;
497 	SCpnt->underflow = this_count << 9;
498 	SCpnt->allowed = MAX_RETRIES;
499 
500 	/*
501 	 * This indicates that the command is ready from our end to be
502 	 * queued.
503 	 */
504 	ret = BLKPREP_OK;
505  out:
506 	return scsi_prep_return(q, rq, ret);
507 }
508 
509 static int sr_block_open(struct block_device *bdev, fmode_t mode)
510 {
511 	struct scsi_cd *cd;
512 	int ret = -ENXIO;
513 
514 	mutex_lock(&sr_mutex);
515 	cd = scsi_cd_get(bdev->bd_disk);
516 	if (cd) {
517 		ret = cdrom_open(&cd->cdi, bdev, mode);
518 		if (ret)
519 			scsi_cd_put(cd);
520 	}
521 	mutex_unlock(&sr_mutex);
522 	return ret;
523 }
524 
525 static int sr_block_release(struct gendisk *disk, fmode_t mode)
526 {
527 	struct scsi_cd *cd = scsi_cd(disk);
528 	mutex_lock(&sr_mutex);
529 	cdrom_release(&cd->cdi, mode);
530 	scsi_cd_put(cd);
531 	mutex_unlock(&sr_mutex);
532 	return 0;
533 }
534 
535 static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
536 			  unsigned long arg)
537 {
538 	struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
539 	struct scsi_device *sdev = cd->device;
540 	void __user *argp = (void __user *)arg;
541 	int ret;
542 
543 	mutex_lock(&sr_mutex);
544 
545 	/*
546 	 * Send SCSI addressing ioctls directly to mid level, send other
547 	 * ioctls to cdrom/block level.
548 	 */
549 	switch (cmd) {
550 	case SCSI_IOCTL_GET_IDLUN:
551 	case SCSI_IOCTL_GET_BUS_NUMBER:
552 		ret = scsi_ioctl(sdev, cmd, argp);
553 		goto out;
554 	}
555 
556 	ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
557 	if (ret != -ENOSYS)
558 		goto out;
559 
560 	/*
561 	 * ENODEV means that we didn't recognise the ioctl, or that we
562 	 * cannot execute it in the current device state.  In either
563 	 * case fall through to scsi_ioctl, which will return ENDOEV again
564 	 * if it doesn't recognise the ioctl
565 	 */
566 	ret = scsi_nonblockable_ioctl(sdev, cmd, argp,
567 					(mode & FMODE_NDELAY) != 0);
568 	if (ret != -ENODEV)
569 		goto out;
570 	ret = scsi_ioctl(sdev, cmd, argp);
571 
572 out:
573 	mutex_unlock(&sr_mutex);
574 	return ret;
575 }
576 
577 static unsigned int sr_block_check_events(struct gendisk *disk,
578 					  unsigned int clearing)
579 {
580 	struct scsi_cd *cd = scsi_cd(disk);
581 	return cdrom_check_events(&cd->cdi, clearing);
582 }
583 
584 static int sr_block_revalidate_disk(struct gendisk *disk)
585 {
586 	struct scsi_cd *cd = scsi_cd(disk);
587 	struct scsi_sense_hdr sshdr;
588 
589 	/* if the unit is not ready, nothing more to do */
590 	if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr))
591 		return 0;
592 
593 	sr_cd_check(&cd->cdi);
594 	get_sectorsize(cd);
595 	return 0;
596 }
597 
598 static const struct block_device_operations sr_bdops =
599 {
600 	.owner		= THIS_MODULE,
601 	.open		= sr_block_open,
602 	.release	= sr_block_release,
603 	.ioctl		= sr_block_ioctl,
604 	.check_events	= sr_block_check_events,
605 	.revalidate_disk = sr_block_revalidate_disk,
606 	/*
607 	 * No compat_ioctl for now because sr_block_ioctl never
608 	 * seems to pass arbitrary ioctls down to host drivers.
609 	 */
610 };
611 
612 static int sr_open(struct cdrom_device_info *cdi, int purpose)
613 {
614 	struct scsi_cd *cd = cdi->handle;
615 	struct scsi_device *sdev = cd->device;
616 	int retval;
617 
618 	/*
619 	 * If the device is in error recovery, wait until it is done.
620 	 * If the device is offline, then disallow any access to it.
621 	 */
622 	retval = -ENXIO;
623 	if (!scsi_block_when_processing_errors(sdev))
624 		goto error_out;
625 
626 	return 0;
627 
628 error_out:
629 	return retval;
630 }
631 
632 static void sr_release(struct cdrom_device_info *cdi)
633 {
634 	struct scsi_cd *cd = cdi->handle;
635 
636 	if (cd->device->sector_size > 2048)
637 		sr_set_blocklength(cd, 2048);
638 
639 }
640 
641 static int sr_probe(struct device *dev)
642 {
643 	struct scsi_device *sdev = to_scsi_device(dev);
644 	struct gendisk *disk;
645 	struct scsi_cd *cd;
646 	int minor, error;
647 
648 	error = -ENODEV;
649 	if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)
650 		goto fail;
651 
652 	error = -ENOMEM;
653 	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
654 	if (!cd)
655 		goto fail;
656 
657 	kref_init(&cd->kref);
658 
659 	disk = alloc_disk(1);
660 	if (!disk)
661 		goto fail_free;
662 
663 	spin_lock(&sr_index_lock);
664 	minor = find_first_zero_bit(sr_index_bits, SR_DISKS);
665 	if (minor == SR_DISKS) {
666 		spin_unlock(&sr_index_lock);
667 		error = -EBUSY;
668 		goto fail_put;
669 	}
670 	__set_bit(minor, sr_index_bits);
671 	spin_unlock(&sr_index_lock);
672 
673 	disk->major = SCSI_CDROM_MAJOR;
674 	disk->first_minor = minor;
675 	sprintf(disk->disk_name, "sr%d", minor);
676 	disk->fops = &sr_bdops;
677 	disk->flags = GENHD_FL_CD | GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE;
678 	disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST;
679 
680 	blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
681 
682 	cd->device = sdev;
683 	cd->disk = disk;
684 	cd->driver = &sr_template;
685 	cd->disk = disk;
686 	cd->capacity = 0x1fffff;
687 	cd->device->changed = 1;	/* force recheck CD type */
688 	cd->media_present = 1;
689 	cd->use = 1;
690 	cd->readcd_known = 0;
691 	cd->readcd_cdda = 0;
692 
693 	cd->cdi.ops = &sr_dops;
694 	cd->cdi.handle = cd;
695 	cd->cdi.mask = 0;
696 	cd->cdi.capacity = 1;
697 	sprintf(cd->cdi.name, "sr%d", minor);
698 
699 	sdev->sector_size = 2048;	/* A guess, just in case */
700 
701 	/* FIXME: need to handle a get_capabilities failure properly ?? */
702 	get_capabilities(cd);
703 	blk_queue_prep_rq(sdev->request_queue, sr_prep_fn);
704 	sr_vendor_init(cd);
705 
706 	disk->driverfs_dev = &sdev->sdev_gendev;
707 	set_capacity(disk, cd->capacity);
708 	disk->private_data = &cd->driver;
709 	disk->queue = sdev->request_queue;
710 	cd->cdi.disk = disk;
711 
712 	if (register_cdrom(&cd->cdi))
713 		goto fail_put;
714 
715 	dev_set_drvdata(dev, cd);
716 	disk->flags |= GENHD_FL_REMOVABLE;
717 	add_disk(disk);
718 
719 	sdev_printk(KERN_DEBUG, sdev,
720 		    "Attached scsi CD-ROM %s\n", cd->cdi.name);
721 	return 0;
722 
723 fail_put:
724 	put_disk(disk);
725 fail_free:
726 	kfree(cd);
727 fail:
728 	return error;
729 }
730 
731 
732 static void get_sectorsize(struct scsi_cd *cd)
733 {
734 	unsigned char cmd[10];
735 	unsigned char buffer[8];
736 	int the_result, retries = 3;
737 	int sector_size;
738 	struct request_queue *queue;
739 
740 	do {
741 		cmd[0] = READ_CAPACITY;
742 		memset((void *) &cmd[1], 0, 9);
743 		memset(buffer, 0, sizeof(buffer));
744 
745 		/* Do the command and wait.. */
746 		the_result = scsi_execute_req(cd->device, cmd, DMA_FROM_DEVICE,
747 					      buffer, sizeof(buffer), NULL,
748 					      SR_TIMEOUT, MAX_RETRIES, NULL);
749 
750 		retries--;
751 
752 	} while (the_result && retries);
753 
754 
755 	if (the_result) {
756 		cd->capacity = 0x1fffff;
757 		sector_size = 2048;	/* A guess, just in case */
758 	} else {
759 		long last_written;
760 
761 		cd->capacity = 1 + ((buffer[0] << 24) | (buffer[1] << 16) |
762 				    (buffer[2] << 8) | buffer[3]);
763 		/*
764 		 * READ_CAPACITY doesn't return the correct size on
765 		 * certain UDF media.  If last_written is larger, use
766 		 * it instead.
767 		 *
768 		 * http://bugzilla.kernel.org/show_bug.cgi?id=9668
769 		 */
770 		if (!cdrom_get_last_written(&cd->cdi, &last_written))
771 			cd->capacity = max_t(long, cd->capacity, last_written);
772 
773 		sector_size = (buffer[4] << 24) |
774 		    (buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
775 		switch (sector_size) {
776 			/*
777 			 * HP 4020i CD-Recorder reports 2340 byte sectors
778 			 * Philips CD-Writers report 2352 byte sectors
779 			 *
780 			 * Use 2k sectors for them..
781 			 */
782 		case 0:
783 		case 2340:
784 		case 2352:
785 			sector_size = 2048;
786 			/* fall through */
787 		case 2048:
788 			cd->capacity *= 4;
789 			/* fall through */
790 		case 512:
791 			break;
792 		default:
793 			printk("%s: unsupported sector size %d.\n",
794 			       cd->cdi.name, sector_size);
795 			cd->capacity = 0;
796 		}
797 
798 		cd->device->sector_size = sector_size;
799 
800 		/*
801 		 * Add this so that we have the ability to correctly gauge
802 		 * what the device is capable of.
803 		 */
804 		set_capacity(cd->disk, cd->capacity);
805 	}
806 
807 	queue = cd->device->request_queue;
808 	blk_queue_logical_block_size(queue, sector_size);
809 
810 	return;
811 }
812 
813 static void get_capabilities(struct scsi_cd *cd)
814 {
815 	unsigned char *buffer;
816 	struct scsi_mode_data data;
817 	struct scsi_sense_hdr sshdr;
818 	int rc, n;
819 
820 	static const char *loadmech[] =
821 	{
822 		"caddy",
823 		"tray",
824 		"pop-up",
825 		"",
826 		"changer",
827 		"cartridge changer",
828 		"",
829 		""
830 	};
831 
832 
833 	/* allocate transfer buffer */
834 	buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
835 	if (!buffer) {
836 		printk(KERN_ERR "sr: out of memory.\n");
837 		return;
838 	}
839 
840 	/* eat unit attentions */
841 	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
842 
843 	/* ask for mode page 0x2a */
844 	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, 128,
845 			     SR_TIMEOUT, 3, &data, NULL);
846 
847 	if (!scsi_status_is_good(rc)) {
848 		/* failed, drive doesn't have capabilities mode page */
849 		cd->cdi.speed = 1;
850 		cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
851 				 CDC_DVD | CDC_DVD_RAM |
852 				 CDC_SELECT_DISC | CDC_SELECT_SPEED |
853 				 CDC_MRW | CDC_MRW_W | CDC_RAM);
854 		kfree(buffer);
855 		printk("%s: scsi-1 drive\n", cd->cdi.name);
856 		return;
857 	}
858 
859 	n = data.header_length + data.block_descriptor_length;
860 	cd->cdi.speed = ((buffer[n + 8] << 8) + buffer[n + 9]) / 176;
861 	cd->readcd_known = 1;
862 	cd->readcd_cdda = buffer[n + 5] & 0x01;
863 	/* print some capability bits */
864 	printk("%s: scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n", cd->cdi.name,
865 	       ((buffer[n + 14] << 8) + buffer[n + 15]) / 176,
866 	       cd->cdi.speed,
867 	       buffer[n + 3] & 0x01 ? "writer " : "", /* CD Writer */
868 	       buffer[n + 3] & 0x20 ? "dvd-ram " : "",
869 	       buffer[n + 2] & 0x02 ? "cd/rw " : "", /* can read rewriteable */
870 	       buffer[n + 4] & 0x20 ? "xa/form2 " : "",	/* can read xa/from2 */
871 	       buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
872 	       loadmech[buffer[n + 6] >> 5]);
873 	if ((buffer[n + 6] >> 5) == 0)
874 		/* caddy drives can't close tray... */
875 		cd->cdi.mask |= CDC_CLOSE_TRAY;
876 	if ((buffer[n + 2] & 0x8) == 0)
877 		/* not a DVD drive */
878 		cd->cdi.mask |= CDC_DVD;
879 	if ((buffer[n + 3] & 0x20) == 0)
880 		/* can't write DVD-RAM media */
881 		cd->cdi.mask |= CDC_DVD_RAM;
882 	if ((buffer[n + 3] & 0x10) == 0)
883 		/* can't write DVD-R media */
884 		cd->cdi.mask |= CDC_DVD_R;
885 	if ((buffer[n + 3] & 0x2) == 0)
886 		/* can't write CD-RW media */
887 		cd->cdi.mask |= CDC_CD_RW;
888 	if ((buffer[n + 3] & 0x1) == 0)
889 		/* can't write CD-R media */
890 		cd->cdi.mask |= CDC_CD_R;
891 	if ((buffer[n + 6] & 0x8) == 0)
892 		/* can't eject */
893 		cd->cdi.mask |= CDC_OPEN_TRAY;
894 
895 	if ((buffer[n + 6] >> 5) == mechtype_individual_changer ||
896 	    (buffer[n + 6] >> 5) == mechtype_cartridge_changer)
897 		cd->cdi.capacity =
898 		    cdrom_number_of_slots(&cd->cdi);
899 	if (cd->cdi.capacity <= 1)
900 		/* not a changer */
901 		cd->cdi.mask |= CDC_SELECT_DISC;
902 	/*else    I don't think it can close its tray
903 		cd->cdi.mask |= CDC_CLOSE_TRAY; */
904 
905 	/*
906 	 * if DVD-RAM, MRW-W or CD-RW, we are randomly writable
907 	 */
908 	if ((cd->cdi.mask & (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) !=
909 			(CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) {
910 		cd->device->writeable = 1;
911 	}
912 
913 	kfree(buffer);
914 }
915 
916 /*
917  * sr_packet() is the entry point for the generic commands generated
918  * by the Uniform CD-ROM layer.
919  */
920 static int sr_packet(struct cdrom_device_info *cdi,
921 		struct packet_command *cgc)
922 {
923 	struct scsi_cd *cd = cdi->handle;
924 	struct scsi_device *sdev = cd->device;
925 
926 	if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info)
927 		return -EDRIVE_CANT_DO_THIS;
928 
929 	if (cgc->timeout <= 0)
930 		cgc->timeout = IOCTL_TIMEOUT;
931 
932 	sr_do_ioctl(cd, cgc);
933 
934 	return cgc->stat;
935 }
936 
937 /**
938  *	sr_kref_release - Called to free the scsi_cd structure
939  *	@kref: pointer to embedded kref
940  *
941  *	sr_ref_mutex must be held entering this routine.  Because it is
942  *	called on last put, you should always use the scsi_cd_get()
943  *	scsi_cd_put() helpers which manipulate the semaphore directly
944  *	and never do a direct kref_put().
945  **/
946 static void sr_kref_release(struct kref *kref)
947 {
948 	struct scsi_cd *cd = container_of(kref, struct scsi_cd, kref);
949 	struct gendisk *disk = cd->disk;
950 
951 	spin_lock(&sr_index_lock);
952 	clear_bit(MINOR(disk_devt(disk)), sr_index_bits);
953 	spin_unlock(&sr_index_lock);
954 
955 	unregister_cdrom(&cd->cdi);
956 
957 	disk->private_data = NULL;
958 
959 	put_disk(disk);
960 
961 	kfree(cd);
962 }
963 
964 static int sr_remove(struct device *dev)
965 {
966 	struct scsi_cd *cd = dev_get_drvdata(dev);
967 
968 	blk_queue_prep_rq(cd->device->request_queue, scsi_prep_fn);
969 	del_gendisk(cd->disk);
970 
971 	mutex_lock(&sr_ref_mutex);
972 	kref_put(&cd->kref, sr_kref_release);
973 	mutex_unlock(&sr_ref_mutex);
974 
975 	return 0;
976 }
977 
978 static int __init init_sr(void)
979 {
980 	int rc;
981 
982 	rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
983 	if (rc)
984 		return rc;
985 	rc = scsi_register_driver(&sr_template.gendrv);
986 	if (rc)
987 		unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
988 
989 	return rc;
990 }
991 
992 static void __exit exit_sr(void)
993 {
994 	scsi_unregister_driver(&sr_template.gendrv);
995 	unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
996 }
997 
998 module_init(init_sr);
999 module_exit(exit_sr);
1000 MODULE_LICENSE("GPL");
1001