xref: /openbsd/usr.bin/cdio/mmc.c (revision 8529ddd3)
1 /*	$OpenBSD: mmc.c,v 1.30 2015/01/16 06:40:06 deraadt Exp $	*/
2 /*
3  * Copyright (c) 2006 Michael Coulter <mjc@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/limits.h>
19 #include <sys/types.h>
20 #include <sys/scsiio.h>
21 #include <sys/param.h>	/* setbit, isset */
22 #include <scsi/cd.h>
23 #include <scsi/scsi_all.h>
24 #include <scsi/scsi_disk.h>
25 #include <err.h>
26 #include <errno.h>
27 #include <fcntl.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <unistd.h>
31 #include "extern.h"
32 
33 extern int fd;
34 extern u_int8_t mediacap[];
35 extern char *cdname;
36 extern int verbose;
37 
38 #define SCSI_GET_CONFIGURATION		0x46
39 
40 #define MMC_FEATURE_HDR_LEN		8
41 
42 static const struct {
43 	u_int16_t id;
44 	char *name;
45 } mmc_feature[] = {
46 	{ 0x0000, "Profile List" },
47 	{ 0x0001, "Core" },
48 	{ 0x0002, "Morphing" },
49 	{ 0x0003, "Removable Medium" },
50 	{ 0x0004, "Write Protect" },
51 	{ 0x0010, "Random Readable" },
52 	{ 0x001d, "Multi-Read" },
53 	{ 0x001e, "CD Read" },
54 	{ 0x001f, "DVD Read" },
55 	{ 0x0020, "Random Writable" },
56 	{ 0x0021, "Incremental Streaming Writable" },
57 	{ 0x0022, "Sector Erasable" },
58 	{ 0x0023, "Formattable" },
59 	{ 0x0024, "Hardware Defect Management" },
60 	{ 0x0025, "Write Once" },
61 	{ 0x0026, "Restricted Overwrite" },
62 	{ 0x0027, "CD-RW CAV Write" },
63 	{ 0x0028, "MRW" },
64 	{ 0x0029, "Enhanced Defect Reporting" },
65 	{ 0x002a, "DVD+RW" },
66 	{ 0x002b, "DVD+R" },
67 	{ 0x002c, "Rigid Restricted Overwrite" },
68 	{ 0x002d, "CD Track at Once (TAO)" },
69 	{ 0x002e, "CD Mastering (Session at Once)" },
70 	{ 0x002f, "DVD-RW Write" },
71 	{ 0x0030, "DDCD-ROM (Legacy)" },
72 	{ 0x0031, "DDCD-R (Legacy)" },
73 	{ 0x0032, "DDCD-RW (Legacy)" },
74 	{ 0x0033, "Layer Jump Recording" },
75 	{ 0x0037, "CD-RW Media Write Support" },
76 	{ 0x0038, "BD-R Pseudo-Overwrite (POW)" },
77 	{ 0x003a, "DVD+RW Dual Layer" },
78 	{ 0x003b, "DVD+R Dual Layer" },
79 	{ 0x0040, "BD Read" },
80 	{ 0x0041, "BD Write" },
81 	{ 0x0042, "Timely Safe Recording (TSR)" },
82 	{ 0x0050, "HD DVD Read" },
83 	{ 0x0051, "HD DVD Write" },
84 	{ 0x0080, "Hybrid Disc" },
85 	{ 0x0100, "Power Management" },
86 	{ 0x0101, "S.M.A.R.T." },
87 	{ 0x0102, "Embedded Changer" },
88 	{ 0x0103, "CD Audio External Play (Legacy)" },
89 	{ 0x0104, "Microcode Upgrade" },
90 	{ 0x0105, "Timeout" },
91 	{ 0x0106, "DVD CSS" },
92 	{ 0x0107, "Real Time Streaming" },
93 	{ 0x0108, "Drive Serial Number" },
94 	{ 0x0109, "Media Serial Number" },
95 	{ 0x010a, "Disc Control Blocks (DCBs)" },
96 	{ 0x010b, "DVD CPRM" },
97 	{ 0x010c, "Firmware Information" },
98 	{ 0x010d, "AACS" },
99 	{ 0x0110, "VCPS" },
100 	{ 0, NULL }
101 };
102 
103 static const struct {
104 	u_int16_t id;
105 	char *name;
106 } mmc_profile[] = {
107 	{ 0x0001, "Re-writable disk, capable of changing behaviour" },
108 	{ 0x0002, "Re-writable, with removable media" },
109 	{ 0x0003, "Magneto-Optical disk with sector erase capability" },
110 	{ 0x0004, "Optical write once" },
111 	{ 0x0005, "Advance Storage -- Magneto-Optical" },
112 	{ 0x0008, "Read only Compact Disc" },
113 	{ 0x0009, "Write once Compact Disc" },
114 	{ 0x000a, "Re-writable Compact Disc" },
115 	{ 0x0010, "Read only DVD" },
116 	{ 0x0011, "Write once DVD using Sequential recording" },
117 	{ 0x0012, "Re-writable DVD" },
118 	{ 0x0013, "Re-recordable DVD using Restricted Overwrite" },
119 	{ 0x0014, "Re-recordable DVD using Sequential recording" },
120 	{ 0x0015, "Dual Layer DVD-R using Sequential recording" },
121 	{ 0x0016, "Dual Layer DVD-R using Layer Jump recording" },
122 	{ 0x001a, "DVD+ReWritable" },
123 	{ 0x001b, "DVD+Recordable" },
124 	{ 0x0020, "DDCD-ROM" },
125 	{ 0x0021, "DDCD-R" },
126 	{ 0x0022, "DDCD-RW" },
127 	{ 0x002a, "DVD+Rewritable Dual Layer" },
128 	{ 0x002b, "DVD+Recordable Dual Layer" },
129 	{ 0x003e, "Blu-ray Disc ROM" },
130 	{ 0x003f, "Blu-ray Disc Recordable -- Sequential Recording Mode" },
131 	{ 0x0040, "Blu-ray Disc Recordable -- Random Recording Mode" },
132 	{ 0x0041, "Blu-ray Disc Rewritable" },
133 	{ 0x004e, "Read-only HD DVD" },
134 	{ 0x004f, "Write-once HD DVD" },
135 	{ 0x0050, "Rewritable HD DVD" },
136 	{ 0, NULL }
137 };
138 
139 int
140 get_media_type(void)
141 {
142 	scsireq_t scr;
143 	char buf[32];
144 	u_char disctype;
145 	int rv, error;
146 
147 	rv = MEDIATYPE_UNKNOWN;
148 	memset(buf, 0, sizeof(buf));
149 	memset(&scr, 0, sizeof(scr));
150 
151 	scr.cmd[0] = READ_TOC;
152 	scr.cmd[1] = 0x2;	/* MSF */
153 	scr.cmd[2] = 0x4;	/* ATIP */
154 	scr.cmd[8] = 0x20;
155 
156 	scr.flags = SCCMD_ESCAPE | SCCMD_READ;
157 	scr.databuf = buf;
158 	scr.datalen = sizeof(buf);
159 	scr.cmdlen = 10;
160 	scr.timeout = 120000;
161 	scr.senselen = SENSEBUFLEN;
162 
163 	error = ioctl(fd, SCIOCCOMMAND, &scr);
164 	if (error != -1 && scr.retsts == SCCMD_OK && scr.datalen_used > 7) {
165 		disctype = (buf[6] >> 6) & 0x1;
166 		if (disctype == 0)
167 			rv = MEDIATYPE_CDR;
168 		else if (disctype == 1)
169 			rv = MEDIATYPE_CDRW;
170 	}
171 
172 	return (rv);
173 }
174 
175 int
176 get_media_capabilities(u_int8_t *cap, int rt)
177 {
178 	scsireq_t scr;
179 	u_char buf[4096];
180 	u_int32_t i, dlen;
181 	u_int16_t feature, profile, tmp;
182 	u_int8_t feature_len;
183 	int current, error, j, k;
184 
185 	memset(cap, 0, MMC_FEATURE_MAX / NBBY);
186 	memset(buf, 0, sizeof(buf));
187 	memset(&scr, 0, sizeof(scr));
188 
189 	scr.cmd[0] = SCSI_GET_CONFIGURATION;
190 	scr.cmd[1] = rt;
191 	tmp = htobe16(sizeof(buf));
192 	memcpy(scr.cmd + 7, &tmp, sizeof(u_int16_t));
193 
194 	scr.flags = SCCMD_ESCAPE | SCCMD_READ;
195 	scr.databuf = buf;
196 	scr.datalen = sizeof(buf);
197 	scr.cmdlen = 10;
198 	scr.timeout = 120000;
199 	scr.senselen = SENSEBUFLEN;
200 
201 	error = ioctl(fd, SCIOCCOMMAND, &scr);
202 	if (error == -1 || scr.retsts != SCCMD_OK)
203 		return (-1);
204 	if (scr.datalen_used < MMC_FEATURE_HDR_LEN)
205 		return (-1);	/* Can't get the header. */
206 
207 	/* Include the whole header in the length. */
208 	dlen = betoh32(*(u_int32_t *)buf) + 4;
209 	if (dlen > scr.datalen_used)
210 		dlen = scr.datalen_used;
211 
212 	if (verbose > 1)
213 		printf("Features:\n");
214 	for (i = MMC_FEATURE_HDR_LEN; i + 3 < dlen; i += feature_len) {
215 		feature_len = buf[i + 3] + 4;
216 		if (feature_len + i > dlen)
217 			break;
218 
219 		feature = betoh16(*(u_int16_t *)(buf + i));
220 		if (feature >= MMC_FEATURE_MAX)
221 			break;
222 
223 		if (verbose > 1) {
224 			printf("0x%04x", feature);
225 			for (j = 0; mmc_feature[j].name != NULL; j++)
226 				if (feature == mmc_feature[j].id)
227 					break;
228 			if (mmc_feature[j].name == NULL)
229 				printf(" <Undocumented>");
230 			else
231 				printf(" %s", mmc_feature[j].name);
232 			if (feature_len > 4)
233 				printf(" (%d bytes of data)", feature_len - 4);
234 			printf("\n");
235 			if (verbose > 2) {
236 				printf("    ");
237 				for (j = i; j < i + feature_len; j++) {
238 					printf("%02x", buf[j]);
239 					if ((j + 1) == (i + feature_len))
240 						printf("\n");
241 					else if ((j > i) && ((j - i + 1) % 16
242 					    == 0))
243 						printf("\n    ");
244 					else if ((j - i) == 3)
245 						printf("|");
246 					else
247 						printf(" ");
248 				}
249 			}
250 		}
251 		if (feature == 0 && verbose > 1) {
252 			if (verbose > 2)
253 				printf("    Profiles:\n");
254 			for (j = i + 4; j < i + feature_len; j += 4) {
255 				profile = betoh16(*(u_int16_t *)(buf+j));
256 				current = buf[j+2] == 1;
257 				if (verbose < 3 && !current)
258 					continue;
259 				if (current)
260 					printf("  * ");
261 				else
262 					printf("    ");
263 				printf("0x%04x", profile);
264 				for (k = 0; mmc_profile[k].name != NULL; k++)
265 					if (profile == mmc_profile[k].id)
266 						break;
267 				if (mmc_profile[k].name == NULL)
268 					printf(" <Undocumented>");
269 				else
270 					printf(" %s", mmc_profile[k].name);
271 				printf(" %s\n", current ? "[Current Profile]" :
272 				    "" );
273 			}
274 		}
275 		setbit(cap, feature);
276 	}
277 
278 	return (0);
279 }
280 
281 static int
282 set_speed(int wspeed)
283 {
284 	scsireq_t scr;
285 	int r;
286 
287 	memset(&scr, 0, sizeof(scr));
288 	scr.cmd[0] = SET_CD_SPEED;
289 	scr.cmd[1] = (isset(mediacap, MMC_FEATURE_CDRW_CAV)) != 0;
290 	*(u_int16_t *)(scr.cmd + 2) = htobe16(DRIVE_SPEED_OPTIMAL);
291 	*(u_int16_t *)(scr.cmd + 4) = htobe16(wspeed);
292 
293 	scr.cmdlen = 12;
294 	scr.datalen = 0;
295 	scr.timeout = 120000;
296 	scr.flags = SCCMD_ESCAPE;
297 	scr.senselen = SENSEBUFLEN;
298 
299 	r = ioctl(fd, SCIOCCOMMAND, &scr);
300 	return (r == 0 ? scr.retsts : -1);
301 }
302 
303 int
304 blank(void)
305 {
306 	struct scsi_blank *scb;
307 	scsireq_t scr;
308 	int r;
309 
310 	bzero(&scr, sizeof(scr));
311 	scb = (struct scsi_blank *)scr.cmd;
312 	scb->opcode = BLANK;
313 	scb->byte2 |= BLANK_MINIMAL;
314 	scr.cmdlen = sizeof(*scb);
315 	scr.datalen = 0;
316 	scr.timeout = 120000;
317 	scr.flags = SCCMD_ESCAPE;
318 	scr.senselen = SENSEBUFLEN;
319 
320 	r = ioctl(fd, SCIOCCOMMAND, &scr);
321 	return (r == 0 ? scr.retsts : -1);
322 }
323 
324 int
325 unit_ready(void)
326 {
327 	struct scsi_test_unit_ready *scb;
328 	scsireq_t scr;
329 	int r;
330 
331 	bzero(&scr, sizeof(scr));
332 	scb = (struct scsi_test_unit_ready *)scr.cmd;
333 	scb->opcode = TEST_UNIT_READY;
334 	scr.cmdlen = sizeof(*scb);
335 	scr.datalen = 0;
336 	scr.timeout = 120000;
337 	scr.flags = SCCMD_ESCAPE;
338 	scr.senselen = SENSEBUFLEN;
339 
340 	r = ioctl(fd, SCIOCCOMMAND, &scr);
341 	return (r == 0 ? scr.retsts : -1);
342 }
343 
344 int
345 synchronize_cache(void)
346 {
347 	struct scsi_synchronize_cache *scb;
348 	scsireq_t scr;
349 	int r;
350 
351 	bzero(&scr, sizeof(scr));
352 	scb = (struct scsi_synchronize_cache *)scr.cmd;
353 	scb->opcode = SYNCHRONIZE_CACHE;
354 	scr.cmdlen = sizeof(*scb);
355 	scr.datalen = 0;
356 	scr.timeout = 120000;
357 	scr.flags = SCCMD_ESCAPE;
358 	scr.senselen = SENSEBUFLEN;
359 
360 	r = ioctl(fd, SCIOCCOMMAND, &scr);
361 	return (r == 0 ? scr.retsts : -1);
362 }
363 
364 int
365 close_session(void)
366 {
367 	struct scsi_close_track *scb;
368 	scsireq_t scr;
369 	int r;
370 
371 	bzero(&scr, sizeof(scr));
372 	scb = (struct scsi_close_track *)scr.cmd;
373 	scb->opcode = CLOSE_TRACK;
374 	scb->closefunc = CT_CLOSE_SESS;
375 	scr.cmdlen = sizeof(*scb);
376 	scr.datalen = 0;
377 	scr.timeout = 120000;
378 	scr.flags = SCCMD_ESCAPE;
379 	scr.senselen = SENSEBUFLEN;
380 
381 	r = ioctl(fd, SCIOCCOMMAND, &scr);
382 	return (r == 0 ? scr.retsts : -1);
383 }
384 
385 int
386 writetao(struct track_head *thp)
387 {
388 	u_char modebuf[70], bdlen;
389 	struct track_info *tr;
390 	int r, track = 0;
391 
392 	if ((r = mode_sense_write(modebuf)) != SCCMD_OK) {
393 		warnx("mode sense failed: %d", r);
394 		return (r);
395 	}
396 	bdlen = modebuf[7];
397 	modebuf[2+8+bdlen] |= 0x40; /* Buffer Underrun Free Enable */
398 	modebuf[2+8+bdlen] |= 0x01; /* change write type to TAO */
399 
400 	SLIST_FOREACH(tr, thp, track_list) {
401 		track++;
402 		switch (tr->type) {
403 		case 'd':
404 			modebuf[3+8+bdlen] = 0x04; /* track mode = data */
405 			modebuf[4+8+bdlen] = 0x08; /* 2048 block track mode */
406 			modebuf[8+8+bdlen] = 0x00; /* turn off XA */
407 			break;
408 		case 'a':
409 			modebuf[3+8+bdlen] = 0x00; /* track mode = audio */
410 			modebuf[4+8+bdlen] = 0x00; /* 2352 block track mode */
411 			modebuf[8+8+bdlen] = 0x00; /* turn off XA */
412 			break;
413 		default:
414 			warn("impossible tracktype detected");
415 			break;
416 		}
417 		while (unit_ready() != SCCMD_OK)
418 			continue;
419 		if ((r = mode_select_write(modebuf)) != SCCMD_OK) {
420 			warnx("mode select failed: %d", r);
421 			return (r);
422 		}
423 
424 		set_speed(tr->speed);
425 		writetrack(tr, track);
426 		synchronize_cache();
427 	}
428 	fprintf(stderr, "Closing session.\n");
429 	close_session();
430 	return (0);
431 }
432 
433 int
434 writetrack(struct track_info *tr, int track)
435 {
436 	struct timeval tv, otv, atv;
437 	u_char databuf[65536], nblk;
438 	u_int end_lba, lba, tmp;
439 	scsireq_t scr;
440 	int r;
441 
442 	nblk = 65535/tr->blklen;
443 	bzero(&scr, sizeof(scr));
444 	scr.timeout = 300000;
445 	scr.cmd[0] = WRITE_BIG;
446 	scr.cmd[1] = 0x00;
447 	scr.cmd[8] = nblk; /* Transfer length in blocks (LSB) */
448 	scr.cmdlen = 10;
449 	scr.databuf = (caddr_t)databuf;
450 	scr.datalen = nblk * tr->blklen;
451 	scr.senselen = SENSEBUFLEN;
452 	scr.flags = SCCMD_ESCAPE|SCCMD_WRITE;
453 
454 	timerclear(&otv);
455 	atv.tv_sec = 1;
456 	atv.tv_usec = 0;
457 
458 	if (get_nwa(&lba) != SCCMD_OK) {
459 		warnx("cannot get next writable address");
460 		return (-1);
461 	}
462 	tmp = htobe32(lba); /* update lba in cdb */
463 	memcpy(&scr.cmd[2], &tmp, sizeof(tmp));
464 
465 	if (tr->sz / tr->blklen + 1 > UINT_MAX || tr->sz < tr->blklen) {
466 		warnx("file %s has invalid size", tr->file);
467 		return (-1);
468 	}
469 	if (tr->sz % tr->blklen) {
470 		warnx("file %s is not multiple of block length %d",
471 		    tr->file, tr->blklen);
472 		end_lba = tr->sz / tr->blklen + lba + 1;
473 	} else {
474 		end_lba = tr->sz / tr->blklen + lba;
475 	}
476 	if (lseek(tr->fd, tr->off, SEEK_SET) == -1)
477 		err(1, "seek failed for file %s", tr->file);
478 	while (lba < end_lba && nblk != 0) {
479 		while (lba + nblk <= end_lba) {
480 			read(tr->fd, databuf, nblk * tr->blklen);
481 			scr.cmd[8] = nblk;
482 			scr.datalen = nblk * tr->blklen;
483 again:
484 			r = ioctl(fd, SCIOCCOMMAND, &scr);
485 			if (r != 0) {
486 				printf("\r%60s", "");
487 				warn("ioctl failed while attempting to write");
488 				return (-1);
489 			}
490 			if (scr.retsts == SCCMD_SENSE && scr.sense[2] == 0x2) {
491 				usleep(1000);
492 				goto again;
493 			}
494 			if (scr.retsts != SCCMD_OK) {
495 				printf("\r%60s", "");
496 				warnx("ioctl returned bad status while "
497 				    "attempting to write: %d",
498 				    scr.retsts);
499 				return (r);
500 			}
501 			lba += nblk;
502 
503 			gettimeofday(&tv, NULL);
504 			if (lba == end_lba || timercmp(&tv, &otv, >)) {
505 				fprintf(stderr,
506 				    "\rtrack %02d '%c' %08u/%08u %3d%%",
507 				    track, tr->type,
508 				    lba, end_lba, 100 * lba / end_lba);
509 				timeradd(&tv, &atv, &otv);
510 			}
511 			tmp = htobe32(lba); /* update lba in cdb */
512 			memcpy(&scr.cmd[2], &tmp, sizeof(tmp));
513 		}
514 		nblk--;
515 	}
516 	printf("\n");
517 	close(tr->fd);
518 	return (0);
519 }
520 
521 int
522 mode_sense_write(unsigned char buf[])
523 {
524 	struct scsi_mode_sense_big *scb;
525 	scsireq_t scr;
526 	int r;
527 
528 	bzero(&scr, sizeof(scr));
529 	scb = (struct scsi_mode_sense_big *)scr.cmd;
530 	scb->opcode = MODE_SENSE_BIG;
531 	/* XXX: need to set disable block descriptors and check SCSI drive */
532 	scb->page = WRITE_PARAM_PAGE;
533 	scb->length[1] = 0x46; /* 16 for the header + size from pg. 89 mmc-r10a.pdf */
534 	scr.cmdlen = sizeof(*scb);
535 	scr.timeout = 4000;
536 	scr.senselen = SENSEBUFLEN;
537 	scr.datalen= 0x46;
538 	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
539 	scr.databuf = (caddr_t)buf;
540 
541 	r = ioctl(fd, SCIOCCOMMAND, &scr);
542 	return (r == 0 ? scr.retsts : -1);
543 }
544 
545 int
546 mode_select_write(unsigned char buf[])
547 {
548 	struct scsi_mode_select_big *scb;
549 	scsireq_t scr;
550 	int r;
551 
552 	bzero(&scr, sizeof(scr));
553 	scb = (struct scsi_mode_select_big *)scr.cmd;
554 	scb->opcode = MODE_SELECT_BIG;
555 
556 	/*
557 	 * INF-8020 says bit 4 in byte 2 is '1'
558 	 * INF-8090 refers to it as 'PF(1)' then doesn't
559 	 * describe it.
560 	 */
561 	scb->byte2 = 0x10;
562 	scb->length[1] = 2 + buf[1] + 256 * buf[0];
563 	scr.timeout = 4000;
564 	scr.senselen = SENSEBUFLEN;
565 	scr.cmdlen = sizeof(*scb);
566 	scr.datalen = 2 + buf[1] + 256 * buf[0];
567 	scr.flags = SCCMD_ESCAPE|SCCMD_WRITE;
568 	scr.databuf = (caddr_t)buf;
569 
570 	r = ioctl(fd, SCIOCCOMMAND, &scr);
571 	return (r == 0 ? scr.retsts : -1);
572 }
573 
574 int
575 get_disc_size(off_t *availblk)
576 {
577 	u_char databuf[28];
578 	struct scsi_read_track_info *scb;
579 	scsireq_t scr;
580 	int r, tmp;
581 
582 	bzero(&scr, sizeof(scr));
583 	scb = (struct scsi_read_track_info *)scr.cmd;
584 	scr.timeout = 4000;
585 	scr.senselen = SENSEBUFLEN;
586 	scb->opcode = READ_TRACK_INFO;
587 	scb->addrtype = RTI_TRACK;
588 	scb->addr[3] = 1;
589 	scb->data_len[1] = 0x1c;
590 	scr.cmdlen = sizeof(*scb);
591 	scr.datalen= 0x1c;
592 	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
593 	scr.databuf = (caddr_t)databuf;
594 
595 	r = ioctl(fd, SCIOCCOMMAND, &scr);
596 	memcpy(&tmp, &databuf[16], sizeof(tmp));
597 	*availblk = betoh32(tmp);
598 	return (r == 0 ? scr.retsts : -1);
599 }
600 
601 int
602 get_nwa(int *nwa)
603 {
604 	u_char databuf[28];
605 	scsireq_t scr;
606 	int r, tmp;
607 
608 	bzero(&scr, sizeof(scr));
609 	scr.timeout = 4000;
610 	scr.senselen = SENSEBUFLEN;
611 	scr.cmd[0] = READ_TRACK_INFO;
612 	scr.cmd[1] = 0x01;
613 	scr.cmd[5] = 0xff; /* Invisible Track */
614 	scr.cmd[7] = 0x00;
615 	scr.cmd[8] = 0x1c;
616 	scr.cmdlen = 10;
617 	scr.datalen= 0x1c;
618 	scr.flags = SCCMD_ESCAPE|SCCMD_READ;
619 	scr.databuf = (caddr_t)databuf;
620 
621 	r = ioctl(fd, SCIOCCOMMAND, &scr);
622 	memcpy(&tmp, &databuf[12], sizeof(tmp));
623 	*nwa = betoh32(tmp);
624 	return (r == 0 ? scr.retsts : -1);
625 }
626