summaryrefslogtreecommitdiff
path: root/usr.bin/cdio/mmc.c
blob: 4136815241aa782e284d301a9acd019260440468 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
/*	$OpenBSD: mmc.c,v 1.31 2017/12/23 20:04:23 cheloha Exp $	*/
/*
 * Copyright (c) 2006 Michael Coulter <mjc@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/limits.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/scsiio.h>
#include <sys/param.h>	/* setbit, isset */
#include <scsi/cd.h>
#include <scsi/scsi_all.h>
#include <scsi/scsi_disk.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "extern.h"

extern int fd;
extern u_int8_t mediacap[];
extern char *cdname;
extern int verbose;

#define SCSI_GET_CONFIGURATION		0x46

#define MMC_FEATURE_HDR_LEN		8

static const struct {
	u_int16_t id;
	char *name;
} mmc_feature[] = {
	{ 0x0000, "Profile List" },
	{ 0x0001, "Core" },
	{ 0x0002, "Morphing" },
	{ 0x0003, "Removable Medium" },
	{ 0x0004, "Write Protect" },
	{ 0x0010, "Random Readable" },
	{ 0x001d, "Multi-Read" },
	{ 0x001e, "CD Read" },
	{ 0x001f, "DVD Read" },
	{ 0x0020, "Random Writable" },
	{ 0x0021, "Incremental Streaming Writable" },
	{ 0x0022, "Sector Erasable" },
	{ 0x0023, "Formattable" },
	{ 0x0024, "Hardware Defect Management" },
	{ 0x0025, "Write Once" },
	{ 0x0026, "Restricted Overwrite" },
	{ 0x0027, "CD-RW CAV Write" },
	{ 0x0028, "MRW" },
	{ 0x0029, "Enhanced Defect Reporting" },
	{ 0x002a, "DVD+RW" },
	{ 0x002b, "DVD+R" },
	{ 0x002c, "Rigid Restricted Overwrite" },
	{ 0x002d, "CD Track at Once (TAO)" },
	{ 0x002e, "CD Mastering (Session at Once)" },
	{ 0x002f, "DVD-RW Write" },
	{ 0x0030, "DDCD-ROM (Legacy)" },
	{ 0x0031, "DDCD-R (Legacy)" },
	{ 0x0032, "DDCD-RW (Legacy)" },
	{ 0x0033, "Layer Jump Recording" },
	{ 0x0037, "CD-RW Media Write Support" },
	{ 0x0038, "BD-R Pseudo-Overwrite (POW)" },
	{ 0x003a, "DVD+RW Dual Layer" },
	{ 0x003b, "DVD+R Dual Layer" },
	{ 0x0040, "BD Read" },
	{ 0x0041, "BD Write" },
	{ 0x0042, "Timely Safe Recording (TSR)" },
	{ 0x0050, "HD DVD Read" },
	{ 0x0051, "HD DVD Write" },
	{ 0x0080, "Hybrid Disc" },
	{ 0x0100, "Power Management" },
	{ 0x0101, "S.M.A.R.T." },
	{ 0x0102, "Embedded Changer" },
	{ 0x0103, "CD Audio External Play (Legacy)" },
	{ 0x0104, "Microcode Upgrade" },
	{ 0x0105, "Timeout" },
	{ 0x0106, "DVD CSS" },
	{ 0x0107, "Real Time Streaming" },
	{ 0x0108, "Drive Serial Number" },
	{ 0x0109, "Media Serial Number" },
	{ 0x010a, "Disc Control Blocks (DCBs)" },
	{ 0x010b, "DVD CPRM" },
	{ 0x010c, "Firmware Information" },
	{ 0x010d, "AACS" },
	{ 0x0110, "VCPS" },
	{ 0, NULL }
};

static const struct {
	u_int16_t id;
	char *name;
} mmc_profile[] = {
	{ 0x0001, "Re-writable disk, capable of changing behaviour" },
	{ 0x0002, "Re-writable, with removable media" },
	{ 0x0003, "Magneto-Optical disk with sector erase capability" },
	{ 0x0004, "Optical write once" },
	{ 0x0005, "Advance Storage -- Magneto-Optical" },
	{ 0x0008, "Read only Compact Disc" },
	{ 0x0009, "Write once Compact Disc" },
	{ 0x000a, "Re-writable Compact Disc" },
	{ 0x0010, "Read only DVD" },
	{ 0x0011, "Write once DVD using Sequential recording" },
	{ 0x0012, "Re-writable DVD" },
	{ 0x0013, "Re-recordable DVD using Restricted Overwrite" },
	{ 0x0014, "Re-recordable DVD using Sequential recording" },
	{ 0x0015, "Dual Layer DVD-R using Sequential recording" },
	{ 0x0016, "Dual Layer DVD-R using Layer Jump recording" },
	{ 0x001a, "DVD+ReWritable" },
	{ 0x001b, "DVD+Recordable" },
	{ 0x0020, "DDCD-ROM" },
	{ 0x0021, "DDCD-R" },
	{ 0x0022, "DDCD-RW" },
	{ 0x002a, "DVD+Rewritable Dual Layer" },
	{ 0x002b, "DVD+Recordable Dual Layer" },
	{ 0x003e, "Blu-ray Disc ROM" },
	{ 0x003f, "Blu-ray Disc Recordable -- Sequential Recording Mode" },
	{ 0x0040, "Blu-ray Disc Recordable -- Random Recording Mode" },
	{ 0x0041, "Blu-ray Disc Rewritable" },
	{ 0x004e, "Read-only HD DVD" },
	{ 0x004f, "Write-once HD DVD" },
	{ 0x0050, "Rewritable HD DVD" },
	{ 0, NULL }
};

int
get_media_type(void)
{
	scsireq_t scr;
	char buf[32];
	u_char disctype;
	int rv, error;

	rv = MEDIATYPE_UNKNOWN;
	memset(buf, 0, sizeof(buf));
	memset(&scr, 0, sizeof(scr));

	scr.cmd[0] = READ_TOC;
	scr.cmd[1] = 0x2;	/* MSF */
	scr.cmd[2] = 0x4;	/* ATIP */
	scr.cmd[8] = 0x20;

	scr.flags = SCCMD_ESCAPE | SCCMD_READ;
	scr.databuf = buf;
	scr.datalen = sizeof(buf);
	scr.cmdlen = 10;
	scr.timeout = 120000;
	scr.senselen = SENSEBUFLEN;

	error = ioctl(fd, SCIOCCOMMAND, &scr);
	if (error != -1 && scr.retsts == SCCMD_OK && scr.datalen_used > 7) {
		disctype = (buf[6] >> 6) & 0x1;
		if (disctype == 0)
			rv = MEDIATYPE_CDR;
		else if (disctype == 1)
			rv = MEDIATYPE_CDRW;
	}

	return (rv);
}

int
get_media_capabilities(u_int8_t *cap, int rt)
{
	scsireq_t scr;
	u_char buf[4096];
	u_int32_t i, dlen;
	u_int16_t feature, profile, tmp;
	u_int8_t feature_len;
	int current, error, j, k;

	memset(cap, 0, MMC_FEATURE_MAX / NBBY);
	memset(buf, 0, sizeof(buf));
	memset(&scr, 0, sizeof(scr));

	scr.cmd[0] = SCSI_GET_CONFIGURATION;
	scr.cmd[1] = rt;
	tmp = htobe16(sizeof(buf));
	memcpy(scr.cmd + 7, &tmp, sizeof(u_int16_t));

	scr.flags = SCCMD_ESCAPE | SCCMD_READ;
	scr.databuf = buf;
	scr.datalen = sizeof(buf);
	scr.cmdlen = 10;
	scr.timeout = 120000;
	scr.senselen = SENSEBUFLEN;

	error = ioctl(fd, SCIOCCOMMAND, &scr);
	if (error == -1 || scr.retsts != SCCMD_OK)
		return (-1);
	if (scr.datalen_used < MMC_FEATURE_HDR_LEN)
		return (-1);	/* Can't get the header. */

	/* Include the whole header in the length. */
	dlen = betoh32(*(u_int32_t *)buf) + 4;
	if (dlen > scr.datalen_used)
		dlen = scr.datalen_used;

	if (verbose > 1)
		printf("Features:\n");
	for (i = MMC_FEATURE_HDR_LEN; i + 3 < dlen; i += feature_len) {
		feature_len = buf[i + 3] + 4;
		if (feature_len + i > dlen)
			break;

		feature = betoh16(*(u_int16_t *)(buf + i));
		if (feature >= MMC_FEATURE_MAX)
			break;

		if (verbose > 1) {
			printf("0x%04x", feature);
			for (j = 0; mmc_feature[j].name != NULL; j++)
				if (feature == mmc_feature[j].id)
					break;
			if (mmc_feature[j].name == NULL)
				printf(" <Undocumented>");
			else
				printf(" %s", mmc_feature[j].name);
			if (feature_len > 4)
				printf(" (%d bytes of data)", feature_len - 4);
			printf("\n");
			if (verbose > 2) {
				printf("    ");
				for (j = i; j < i + feature_len; j++) {
					printf("%02x", buf[j]);
					if ((j + 1) == (i + feature_len))
						printf("\n");
					else if ((j > i) && ((j - i + 1) % 16
					    == 0))
						printf("\n    ");
					else if ((j - i) == 3)
						printf("|");
					else
						printf(" ");
				}
			}
		}
		if (feature == 0 && verbose > 1) {
			if (verbose > 2)
				printf("    Profiles:\n");
			for (j = i + 4; j < i + feature_len; j += 4) {
				profile = betoh16(*(u_int16_t *)(buf+j));
				current = buf[j+2] == 1;
				if (verbose < 3 && !current)
					continue;
				if (current)
					printf("  * ");
				else
					printf("    ");
				printf("0x%04x", profile);
				for (k = 0; mmc_profile[k].name != NULL; k++)
					if (profile == mmc_profile[k].id)
						break;
				if (mmc_profile[k].name == NULL)
					printf(" <Undocumented>");
				else
					printf(" %s", mmc_profile[k].name);
				printf(" %s\n", current ? "[Current Profile]" :
				    "" );
			}
		}
		setbit(cap, feature);
	}

	return (0);
}

static int
set_speed(int wspeed)
{
	scsireq_t scr;
	int r;

	memset(&scr, 0, sizeof(scr));
	scr.cmd[0] = SET_CD_SPEED;
	scr.cmd[1] = (isset(mediacap, MMC_FEATURE_CDRW_CAV)) != 0;
	*(u_int16_t *)(scr.cmd + 2) = htobe16(DRIVE_SPEED_OPTIMAL);
	*(u_int16_t *)(scr.cmd + 4) = htobe16(wspeed);

	scr.cmdlen = 12;
	scr.datalen = 0;
	scr.timeout = 120000;
	scr.flags = SCCMD_ESCAPE;
	scr.senselen = SENSEBUFLEN;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
blank(void)
{
	struct scsi_blank *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_blank *)scr.cmd;
	scb->opcode = BLANK;
	scb->byte2 |= BLANK_MINIMAL;
	scr.cmdlen = sizeof(*scb);
	scr.datalen = 0;
	scr.timeout = 120000;
	scr.flags = SCCMD_ESCAPE;
	scr.senselen = SENSEBUFLEN;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
unit_ready(void)
{
	struct scsi_test_unit_ready *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_test_unit_ready *)scr.cmd;
	scb->opcode = TEST_UNIT_READY;
	scr.cmdlen = sizeof(*scb);
	scr.datalen = 0;
	scr.timeout = 120000;
	scr.flags = SCCMD_ESCAPE;
	scr.senselen = SENSEBUFLEN;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
synchronize_cache(void)
{
	struct scsi_synchronize_cache *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_synchronize_cache *)scr.cmd;
	scb->opcode = SYNCHRONIZE_CACHE;
	scr.cmdlen = sizeof(*scb);
	scr.datalen = 0;
	scr.timeout = 120000;
	scr.flags = SCCMD_ESCAPE;
	scr.senselen = SENSEBUFLEN;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
close_session(void)
{
	struct scsi_close_track *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_close_track *)scr.cmd;
	scb->opcode = CLOSE_TRACK;
	scb->closefunc = CT_CLOSE_SESS;
	scr.cmdlen = sizeof(*scb);
	scr.datalen = 0;
	scr.timeout = 120000;
	scr.flags = SCCMD_ESCAPE;
	scr.senselen = SENSEBUFLEN;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
writetao(struct track_head *thp)
{
	u_char modebuf[70], bdlen;
	struct track_info *tr;
	int r, track = 0;

	if ((r = mode_sense_write(modebuf)) != SCCMD_OK) {
		warnx("mode sense failed: %d", r);
		return (r);
	}
	bdlen = modebuf[7];
	modebuf[2+8+bdlen] |= 0x40; /* Buffer Underrun Free Enable */
	modebuf[2+8+bdlen] |= 0x01; /* change write type to TAO */

	SLIST_FOREACH(tr, thp, track_list) {
		track++;
		switch (tr->type) {
		case 'd':
			modebuf[3+8+bdlen] = 0x04; /* track mode = data */
			modebuf[4+8+bdlen] = 0x08; /* 2048 block track mode */
			modebuf[8+8+bdlen] = 0x00; /* turn off XA */
			break;
		case 'a':
			modebuf[3+8+bdlen] = 0x00; /* track mode = audio */
			modebuf[4+8+bdlen] = 0x00; /* 2352 block track mode */
			modebuf[8+8+bdlen] = 0x00; /* turn off XA */
			break;
		default:
			warn("impossible tracktype detected");
			break;
		}
		while (unit_ready() != SCCMD_OK)
			continue;
		if ((r = mode_select_write(modebuf)) != SCCMD_OK) {
			warnx("mode select failed: %d", r);
			return (r);
		}

		set_speed(tr->speed);
		writetrack(tr, track);
		synchronize_cache();
	}
	fprintf(stderr, "Closing session.\n");
	close_session();
	return (0);
}

int
writetrack(struct track_info *tr, int track)
{
	struct timespec ts, ots, ats;
	u_char databuf[65536], nblk;
	u_int end_lba, lba, tmp;
	scsireq_t scr;
	int r;

	nblk = 65535/tr->blklen;
	bzero(&scr, sizeof(scr));
	scr.timeout = 300000;
	scr.cmd[0] = WRITE_BIG;
	scr.cmd[1] = 0x00;
	scr.cmd[8] = nblk; /* Transfer length in blocks (LSB) */
	scr.cmdlen = 10;
	scr.databuf = (caddr_t)databuf;
	scr.datalen = nblk * tr->blklen;
	scr.senselen = SENSEBUFLEN;
	scr.flags = SCCMD_ESCAPE|SCCMD_WRITE;

	timespecclear(&ots);
	ats.tv_sec = 1;
	ats.tv_nsec = 0;

	if (get_nwa(&lba) != SCCMD_OK) {
		warnx("cannot get next writable address");
		return (-1);
	}
	tmp = htobe32(lba); /* update lba in cdb */
	memcpy(&scr.cmd[2], &tmp, sizeof(tmp));

	if (tr->sz / tr->blklen + 1 > UINT_MAX || tr->sz < tr->blklen) {
		warnx("file %s has invalid size", tr->file);
		return (-1);
	}
	if (tr->sz % tr->blklen) {
		warnx("file %s is not multiple of block length %d",
		    tr->file, tr->blklen);
		end_lba = tr->sz / tr->blklen + lba + 1;
	} else {
		end_lba = tr->sz / tr->blklen + lba;
	}
	if (lseek(tr->fd, tr->off, SEEK_SET) == -1)
		err(1, "seek failed for file %s", tr->file);
	while (lba < end_lba && nblk != 0) {
		while (lba + nblk <= end_lba) {
			read(tr->fd, databuf, nblk * tr->blklen);
			scr.cmd[8] = nblk;
			scr.datalen = nblk * tr->blklen;
again:
			r = ioctl(fd, SCIOCCOMMAND, &scr);
			if (r != 0) {
				printf("\r%60s", "");
				warn("ioctl failed while attempting to write");
				return (-1);
			}
			if (scr.retsts == SCCMD_SENSE && scr.sense[2] == 0x2) {
				usleep(1000);
				goto again;
			}
			if (scr.retsts != SCCMD_OK) {
				printf("\r%60s", "");
				warnx("ioctl returned bad status while "
				    "attempting to write: %d",
				    scr.retsts);
				return (r);
			}
			lba += nblk;

			clock_gettime(CLOCK_MONOTONIC, &ts);
			if (lba == end_lba || timespeccmp(&ts, &ots, >)) {
				fprintf(stderr,
				    "\rtrack %02d '%c' %08u/%08u %3d%%",
				    track, tr->type,
				    lba, end_lba, 100 * lba / end_lba);
				timespecadd(&ts, &ats, &ots);
			}
			tmp = htobe32(lba); /* update lba in cdb */
			memcpy(&scr.cmd[2], &tmp, sizeof(tmp));
		}
		nblk--;
	}
	printf("\n");
	close(tr->fd);
	return (0);
}

int
mode_sense_write(unsigned char buf[])
{
	struct scsi_mode_sense_big *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_mode_sense_big *)scr.cmd;
	scb->opcode = MODE_SENSE_BIG;
	/* XXX: need to set disable block descriptors and check SCSI drive */
	scb->page = WRITE_PARAM_PAGE;
	scb->length[1] = 0x46; /* 16 for the header + size from pg. 89 mmc-r10a.pdf */
	scr.cmdlen = sizeof(*scb);
	scr.timeout = 4000;
	scr.senselen = SENSEBUFLEN;
	scr.datalen= 0x46;
	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
	scr.databuf = (caddr_t)buf;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
mode_select_write(unsigned char buf[])
{
	struct scsi_mode_select_big *scb;
	scsireq_t scr;
	int r;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_mode_select_big *)scr.cmd;
	scb->opcode = MODE_SELECT_BIG;

	/*
	 * INF-8020 says bit 4 in byte 2 is '1'
	 * INF-8090 refers to it as 'PF(1)' then doesn't
	 * describe it.
	 */
	scb->byte2 = 0x10;
	scb->length[1] = 2 + buf[1] + 256 * buf[0];
	scr.timeout = 4000;
	scr.senselen = SENSEBUFLEN;
	scr.cmdlen = sizeof(*scb);
	scr.datalen = 2 + buf[1] + 256 * buf[0];
	scr.flags = SCCMD_ESCAPE|SCCMD_WRITE;
	scr.databuf = (caddr_t)buf;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	return (r == 0 ? scr.retsts : -1);
}

int
get_disc_size(off_t *availblk)
{
	u_char databuf[28];
	struct scsi_read_track_info *scb;
	scsireq_t scr;
	int r, tmp;

	bzero(&scr, sizeof(scr));
	scb = (struct scsi_read_track_info *)scr.cmd;
	scr.timeout = 4000;
	scr.senselen = SENSEBUFLEN;
	scb->opcode = READ_TRACK_INFO;
	scb->addrtype = RTI_TRACK;
	scb->addr[3] = 1;
	scb->data_len[1] = 0x1c;
	scr.cmdlen = sizeof(*scb);
	scr.datalen= 0x1c;
	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
	scr.databuf = (caddr_t)databuf;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	memcpy(&tmp, &databuf[16], sizeof(tmp));
	*availblk = betoh32(tmp);
	return (r == 0 ? scr.retsts : -1);
}

int
get_nwa(int *nwa)
{
	u_char databuf[28];
	scsireq_t scr;
	int r, tmp;

	bzero(&scr, sizeof(scr));
	scr.timeout = 4000;
	scr.senselen = SENSEBUFLEN;
	scr.cmd[0] = READ_TRACK_INFO;
	scr.cmd[1] = 0x01;
	scr.cmd[5] = 0xff; /* Invisible Track */
	scr.cmd[7] = 0x00;
	scr.cmd[8] = 0x1c;
	scr.cmdlen = 10;
	scr.datalen= 0x1c;
	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
	scr.databuf = (caddr_t)databuf;

	r = ioctl(fd, SCIOCCOMMAND, &scr);
	memcpy(&tmp, &databuf[12], sizeof(tmp));
	*nwa = betoh32(tmp);
	return (r == 0 ? scr.retsts : -1);
}