xref: /netbsd-src/sys/dev/ld.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: ld.c,v 1.111 2020/08/02 01:17:56 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran and Charles M. Hannum.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Disk driver for use by RAID controllers.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: ld.c,v 1.111 2020/08/02 01:17:56 riastradh Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/device.h>
43 #include <sys/queue.h>
44 #include <sys/proc.h>
45 #include <sys/buf.h>
46 #include <sys/bufq.h>
47 #include <sys/endian.h>
48 #include <sys/disklabel.h>
49 #include <sys/disk.h>
50 #include <sys/dkio.h>
51 #include <sys/stat.h>
52 #include <sys/conf.h>
53 #include <sys/fcntl.h>
54 #include <sys/vnode.h>
55 #include <sys/syslog.h>
56 #include <sys/mutex.h>
57 #include <sys/module.h>
58 #include <sys/reboot.h>
59 
60 #include <dev/ldvar.h>
61 
62 #include "ioconf.h"
63 
64 static void	ldminphys(struct buf *bp);
65 static bool	ld_suspend(device_t, const pmf_qual_t *);
66 static bool	ld_shutdown(device_t, int);
67 static int	ld_diskstart(device_t, struct buf *bp);
68 static void	ld_iosize(device_t, int *);
69 static int	ld_dumpblocks(device_t, void *, daddr_t, int);
70 static void	ld_fake_geometry(struct ld_softc *);
71 static void	ld_set_geometry(struct ld_softc *);
72 static void	ld_config_interrupts (device_t);
73 static int	ld_lastclose(device_t);
74 static int	ld_discard(device_t, off_t, off_t);
75 static int	ld_flush(device_t, bool);
76 
77 static dev_type_open(ldopen);
78 static dev_type_close(ldclose);
79 static dev_type_read(ldread);
80 static dev_type_write(ldwrite);
81 static dev_type_ioctl(ldioctl);
82 static dev_type_strategy(ldstrategy);
83 static dev_type_dump(lddump);
84 static dev_type_size(ldsize);
85 static dev_type_discard(lddiscard);
86 
87 const struct bdevsw ld_bdevsw = {
88 	.d_open = ldopen,
89 	.d_close = ldclose,
90 	.d_strategy = ldstrategy,
91 	.d_ioctl = ldioctl,
92 	.d_dump = lddump,
93 	.d_psize = ldsize,
94 	.d_discard = lddiscard,
95 	.d_flag = D_DISK | D_MPSAFE
96 };
97 
98 const struct cdevsw ld_cdevsw = {
99 	.d_open = ldopen,
100 	.d_close = ldclose,
101 	.d_read = ldread,
102 	.d_write = ldwrite,
103 	.d_ioctl = ldioctl,
104 	.d_stop = nostop,
105 	.d_tty = notty,
106 	.d_poll = nopoll,
107 	.d_mmap = nommap,
108 	.d_kqfilter = nokqfilter,
109 	.d_discard = lddiscard,
110 	.d_flag = D_DISK | D_MPSAFE
111 };
112 
113 static const struct	dkdriver lddkdriver = {
114 	.d_open = ldopen,
115 	.d_close = ldclose,
116 	.d_strategy = ldstrategy,
117 	.d_iosize = ld_iosize,
118 	.d_minphys  = ldminphys,
119 	.d_diskstart = ld_diskstart,
120 	.d_dumpblocks = ld_dumpblocks,
121 	.d_lastclose = ld_lastclose,
122 	.d_discard = ld_discard
123 };
124 
125 void
126 ldattach(struct ld_softc *sc, const char *default_strategy)
127 {
128 	device_t self = sc->sc_dv;
129 	struct dk_softc *dksc = &sc->sc_dksc;
130 
131 	mutex_init(&sc->sc_mutex, MUTEX_DEFAULT, IPL_VM);
132 	cv_init(&sc->sc_drain, "lddrain");
133 
134 	if ((sc->sc_flags & LDF_ENABLED) == 0) {
135 		return;
136 	}
137 
138 	/* don't attach a disk that we cannot handle */
139 	if (sc->sc_secsize < DEV_BSIZE) {
140 		sc->sc_flags &= ~LDF_ENABLED;
141 		return;
142 	}
143 
144 	/* Initialise dk and disk structure. */
145 	dk_init(dksc, self, DKTYPE_LD);
146 	disk_init(&dksc->sc_dkdev, dksc->sc_xname, &lddkdriver);
147 
148 	if (sc->sc_maxxfer > MAXPHYS)
149 		sc->sc_maxxfer = MAXPHYS;
150 
151 	/* Build synthetic geometry if necessary. */
152 	if (sc->sc_nheads == 0 || sc->sc_nsectors == 0 ||
153 	    sc->sc_ncylinders == 0)
154 	    ld_fake_geometry(sc);
155 
156 	sc->sc_disksize512 = sc->sc_secperunit * sc->sc_secsize / DEV_BSIZE;
157 
158 	if (sc->sc_flags & LDF_NO_RND)
159 		dksc->sc_flags |= DKF_NO_RND;
160 
161 	/* Attach dk and disk subsystems */
162 	dk_attach(dksc);
163 	disk_attach(&dksc->sc_dkdev);
164 	ld_set_geometry(sc);
165 
166 	bufq_alloc(&dksc->sc_bufq, default_strategy, BUFQ_SORT_RAWBLOCK);
167 
168 	/* Register with PMF */
169 	if (!pmf_device_register1(dksc->sc_dev, ld_suspend, NULL, ld_shutdown))
170 		aprint_error_dev(dksc->sc_dev,
171 		    "couldn't establish power handler\n");
172 
173 	/* Discover wedges on this disk. */
174 	config_interrupts(sc->sc_dv, ld_config_interrupts);
175 }
176 
177 int
178 ldadjqparam(struct ld_softc *sc, int xmax)
179 {
180 
181 	mutex_enter(&sc->sc_mutex);
182 	sc->sc_maxqueuecnt = xmax;
183 	mutex_exit(&sc->sc_mutex);
184 
185 	return (0);
186 }
187 
188 int
189 ldbegindetach(struct ld_softc *sc, int flags)
190 {
191 	struct dk_softc *dksc = &sc->sc_dksc;
192 	int error;
193 
194 	/* If we never attached properly, no problem with detaching.  */
195 	if ((sc->sc_flags & LDF_ENABLED) == 0)
196 		return 0;
197 
198 	/*
199 	 * If the disk is still open, back out before we commit to
200 	 * detaching.
201 	 */
202 	error = disk_begindetach(&dksc->sc_dkdev, ld_lastclose, dksc->sc_dev,
203 	    flags);
204 	if (error)
205 		return error;
206 
207 	/* We are now committed to detaching.  Prevent new xfers.  */
208 	ldadjqparam(sc, 0);
209 
210 	return 0;
211 }
212 
213 void
214 ldenddetach(struct ld_softc *sc)
215 {
216 	struct dk_softc *dksc = &sc->sc_dksc;
217 	int bmaj, cmaj, i, mn;
218 
219 	if ((sc->sc_flags & LDF_ENABLED) == 0)
220 		return;
221 
222 	/* Wait for commands queued with the hardware to complete. */
223 	mutex_enter(&sc->sc_mutex);
224 	while (sc->sc_queuecnt > 0) {
225 		if (cv_timedwait(&sc->sc_drain, &sc->sc_mutex, 30 * hz)) {
226 			/*
227 			 * XXX This seems like a recipe for crashing on
228 			 * use after free...
229 			 */
230 			printf("%s: not drained\n", dksc->sc_xname);
231 			break;
232 		}
233 	}
234 	mutex_exit(&sc->sc_mutex);
235 
236 	/* Kill off any queued buffers. */
237 	dk_drain(dksc);
238 	bufq_free(dksc->sc_bufq);
239 
240 	/* Locate the major numbers. */
241 	bmaj = bdevsw_lookup_major(&ld_bdevsw);
242 	cmaj = cdevsw_lookup_major(&ld_cdevsw);
243 
244 	/* Nuke the vnodes for any open instances. */
245 	for (i = 0; i < MAXPARTITIONS; i++) {
246 		mn = DISKMINOR(device_unit(dksc->sc_dev), i);
247 		vdevgone(bmaj, mn, mn, VBLK);
248 		vdevgone(cmaj, mn, mn, VCHR);
249 	}
250 
251 	/* Delete all of our wedges. */
252 	dkwedge_delall(&dksc->sc_dkdev);
253 
254 	/* Detach from the disk list. */
255 	disk_detach(&dksc->sc_dkdev);
256 	disk_destroy(&dksc->sc_dkdev);
257 
258 	dk_detach(dksc);
259 
260 	/* Deregister with PMF */
261 	pmf_device_deregister(dksc->sc_dev);
262 
263 	/*
264 	 * XXX We can't really flush the cache here, because the
265 	 * XXX device may already be non-existent from the controller's
266 	 * XXX perspective.
267 	 */
268 #if 0
269 	ld_flush(dksc->sc_dev, false);
270 #endif
271 	cv_destroy(&sc->sc_drain);
272 	mutex_destroy(&sc->sc_mutex);
273 }
274 
275 /* ARGSUSED */
276 static bool
277 ld_suspend(device_t dev, const pmf_qual_t *qual)
278 {
279 	return ld_shutdown(dev, 0);
280 }
281 
282 /* ARGSUSED */
283 static bool
284 ld_shutdown(device_t dev, int flags)
285 {
286 	if ((flags & RB_NOSYNC) == 0 && ld_flush(dev, true) != 0)
287 		return false;
288 
289 	return true;
290 }
291 
292 /* ARGSUSED */
293 static int
294 ldopen(dev_t dev, int flags, int fmt, struct lwp *l)
295 {
296 	struct ld_softc *sc;
297 	struct dk_softc *dksc;
298 	int unit;
299 
300 	unit = DISKUNIT(dev);
301 	if ((sc = device_lookup_private(&ld_cd, unit)) == NULL)
302 		return (ENXIO);
303 
304 	if ((sc->sc_flags & LDF_ENABLED) == 0)
305 		return (ENODEV);
306 
307 	dksc = &sc->sc_dksc;
308 
309 	return dk_open(dksc, dev, flags, fmt, l);
310 }
311 
312 static int
313 ld_lastclose(device_t self)
314 {
315 	ld_flush(self, false);
316 
317 	return 0;
318 }
319 
320 /* ARGSUSED */
321 static int
322 ldclose(dev_t dev, int flags, int fmt, struct lwp *l)
323 {
324 	struct ld_softc *sc;
325 	struct dk_softc *dksc;
326 	int unit;
327 
328 	unit = DISKUNIT(dev);
329 	sc = device_lookup_private(&ld_cd, unit);
330 	dksc = &sc->sc_dksc;
331 
332 	return dk_close(dksc, dev, flags, fmt, l);
333 }
334 
335 /* ARGSUSED */
336 static int
337 ldread(dev_t dev, struct uio *uio, int ioflag)
338 {
339 
340 	return (physio(ldstrategy, NULL, dev, B_READ, ldminphys, uio));
341 }
342 
343 /* ARGSUSED */
344 static int
345 ldwrite(dev_t dev, struct uio *uio, int ioflag)
346 {
347 
348 	return (physio(ldstrategy, NULL, dev, B_WRITE, ldminphys, uio));
349 }
350 
351 /* ARGSUSED */
352 static int
353 ldioctl(dev_t dev, u_long cmd, void *addr, int32_t flag, struct lwp *l)
354 {
355 	struct ld_softc *sc;
356 	struct dk_softc *dksc;
357 	int unit, error;
358 
359 	unit = DISKUNIT(dev);
360 	sc = device_lookup_private(&ld_cd, unit);
361 	dksc = &sc->sc_dksc;
362 
363 	error = 0;
364 
365 	/*
366 	 * Some common checks so that individual attachments wouldn't need
367 	 * to duplicate them.
368 	 */
369 	switch (cmd) {
370 	case DIOCCACHESYNC:
371 		/*
372 		 * XXX Do we really need to care about having a writable
373 		 * file descriptor here?
374 		 */
375 		if ((flag & FWRITE) == 0)
376 			error = EBADF;
377 		else
378 			error = 0;
379 		break;
380 	}
381 
382 	if (error != 0)
383 		return (error);
384 
385 	if (sc->sc_ioctl) {
386 		if ((sc->sc_flags & LDF_MPSAFE) == 0)
387 			KERNEL_LOCK(1, curlwp);
388 		error = (*sc->sc_ioctl)(sc, cmd, addr, flag, 0);
389 		if ((sc->sc_flags & LDF_MPSAFE) == 0)
390 			KERNEL_UNLOCK_ONE(curlwp);
391 		if (error != EPASSTHROUGH)
392 			return (error);
393 	}
394 
395 	/* something not handled by the attachment */
396 	return dk_ioctl(dksc, dev, cmd, addr, flag, l);
397 }
398 
399 /*
400  * Flush the device's cache.
401  */
402 static int
403 ld_flush(device_t self, bool poll)
404 {
405 	int error = 0;
406 	struct ld_softc *sc = device_private(self);
407 
408 	if (sc->sc_ioctl) {
409 		if ((sc->sc_flags & LDF_MPSAFE) == 0)
410 			KERNEL_LOCK(1, curlwp);
411 		error = (*sc->sc_ioctl)(sc, DIOCCACHESYNC, NULL, 0, poll);
412 		if ((sc->sc_flags & LDF_MPSAFE) == 0)
413 			KERNEL_UNLOCK_ONE(curlwp);
414 		if (error != 0)
415 			device_printf(self, "unable to flush cache\n");
416 	}
417 
418 	return error;
419 }
420 
421 static void
422 ldstrategy(struct buf *bp)
423 {
424 	struct ld_softc *sc;
425 	struct dk_softc *dksc;
426 	int unit;
427 
428 	unit = DISKUNIT(bp->b_dev);
429 	sc = device_lookup_private(&ld_cd, unit);
430 	dksc = &sc->sc_dksc;
431 
432 	dk_strategy(dksc, bp);
433 }
434 
435 static int
436 ld_diskstart(device_t dev, struct buf *bp)
437 {
438 	struct ld_softc *sc = device_private(dev);
439 	int error;
440 
441 	if (sc->sc_queuecnt >= sc->sc_maxqueuecnt)
442 		return EAGAIN;
443 
444 	if ((sc->sc_flags & LDF_MPSAFE) == 0)
445 		KERNEL_LOCK(1, curlwp);
446 
447 	mutex_enter(&sc->sc_mutex);
448 
449 	if (sc->sc_queuecnt >= sc->sc_maxqueuecnt)
450 		error = EAGAIN;
451 	else {
452 		error = (*sc->sc_start)(sc, bp);
453 		if (error == 0)
454 			sc->sc_queuecnt++;
455 	}
456 
457 	mutex_exit(&sc->sc_mutex);
458 
459 	if ((sc->sc_flags & LDF_MPSAFE) == 0)
460 		KERNEL_UNLOCK_ONE(curlwp);
461 
462 	return error;
463 }
464 
465 void
466 lddone(struct ld_softc *sc, struct buf *bp)
467 {
468 	struct dk_softc *dksc = &sc->sc_dksc;
469 
470 	dk_done(dksc, bp);
471 
472 	mutex_enter(&sc->sc_mutex);
473 	if (--sc->sc_queuecnt <= sc->sc_maxqueuecnt) {
474 		cv_broadcast(&sc->sc_drain);
475 		mutex_exit(&sc->sc_mutex);
476 		dk_start(dksc, NULL);
477 	} else
478 		mutex_exit(&sc->sc_mutex);
479 }
480 
481 static int
482 ldsize(dev_t dev)
483 {
484 	struct ld_softc *sc;
485 	struct dk_softc *dksc;
486 	int unit;
487 
488 	unit = DISKUNIT(dev);
489 	if ((sc = device_lookup_private(&ld_cd, unit)) == NULL)
490 		return (-1);
491 	dksc = &sc->sc_dksc;
492 
493 	if ((sc->sc_flags & LDF_ENABLED) == 0)
494 		return (-1);
495 
496 	return dk_size(dksc, dev);
497 }
498 
499 /*
500  * Take a dump.
501  */
502 static int
503 lddump(dev_t dev, daddr_t blkno, void *va, size_t size)
504 {
505 	struct ld_softc *sc;
506 	struct dk_softc *dksc;
507 	int unit;
508 
509 	unit = DISKUNIT(dev);
510 	if ((sc = device_lookup_private(&ld_cd, unit)) == NULL)
511 		return (ENXIO);
512 	dksc = &sc->sc_dksc;
513 
514 	if ((sc->sc_flags & LDF_ENABLED) == 0)
515 		return (ENODEV);
516 
517 	return dk_dump(dksc, dev, blkno, va, size, 0);
518 }
519 
520 static int
521 ld_dumpblocks(device_t dev, void *va, daddr_t blkno, int nblk)
522 {
523 	struct ld_softc *sc = device_private(dev);
524 
525 	if (sc->sc_dump == NULL)
526 		return (ENODEV);
527 
528 	return (*sc->sc_dump)(sc, va, blkno, nblk);
529 }
530 
531 /*
532  * Adjust the size of a transfer.
533  */
534 static void
535 ldminphys(struct buf *bp)
536 {
537 	int unit;
538 	struct ld_softc *sc;
539 
540 	unit = DISKUNIT(bp->b_dev);
541 	sc = device_lookup_private(&ld_cd, unit);
542 
543 	ld_iosize(sc->sc_dv, &bp->b_bcount);
544 	minphys(bp);
545 }
546 
547 static void
548 ld_iosize(device_t d, int *countp)
549 {
550 	struct ld_softc *sc = device_private(d);
551 
552 	if (*countp > sc->sc_maxxfer)
553 		*countp = sc->sc_maxxfer;
554 }
555 
556 static void
557 ld_fake_geometry(struct ld_softc *sc)
558 {
559 	uint64_t ncyl;
560 
561 	if (sc->sc_secperunit <= 528 * 2048)		/* 528MB */
562 		sc->sc_nheads = 16;
563 	else if (sc->sc_secperunit <= 1024 * 2048)	/* 1GB */
564 		sc->sc_nheads = 32;
565 	else if (sc->sc_secperunit <= 21504 * 2048)	/* 21GB */
566 		sc->sc_nheads = 64;
567 	else if (sc->sc_secperunit <= 43008 * 2048)	/* 42GB */
568 		sc->sc_nheads = 128;
569 	else
570 		sc->sc_nheads = 255;
571 
572 	sc->sc_nsectors = 63;
573 	sc->sc_ncylinders = INT_MAX;
574 	ncyl = sc->sc_secperunit /
575 	    (sc->sc_nheads * sc->sc_nsectors);
576 	if (ncyl < INT_MAX)
577 		sc->sc_ncylinders = (int)ncyl;
578 }
579 
580 static void
581 ld_set_geometry(struct ld_softc *sc)
582 {
583 	struct dk_softc *dksc = &sc->sc_dksc;
584 	struct disk_geom *dg = &dksc->sc_dkdev.dk_geom;
585 	char tbuf[9];
586 
587 	format_bytes(tbuf, sizeof(tbuf), sc->sc_secperunit *
588 	    sc->sc_secsize);
589 	aprint_normal_dev(dksc->sc_dev, "%s, %d cyl, %d head, %d sec, "
590 	    "%d bytes/sect x %"PRIu64" sectors\n",
591 	    tbuf, sc->sc_ncylinders, sc->sc_nheads,
592 	    sc->sc_nsectors, sc->sc_secsize, sc->sc_secperunit);
593 
594 	memset(dg, 0, sizeof(*dg));
595 	dg->dg_secperunit = sc->sc_secperunit;
596 	dg->dg_secsize = sc->sc_secsize;
597 	dg->dg_nsectors = sc->sc_nsectors;
598 	dg->dg_ntracks = sc->sc_nheads;
599 	dg->dg_ncylinders = sc->sc_ncylinders;
600 
601 	disk_set_info(dksc->sc_dev, &dksc->sc_dkdev, sc->sc_typename);
602 }
603 
604 static void
605 ld_config_interrupts(device_t d)
606 {
607 	struct ld_softc *sc = device_private(d);
608 	struct dk_softc *dksc = &sc->sc_dksc;
609 
610 	dkwedge_discover(&dksc->sc_dkdev);
611 }
612 
613 static int
614 ld_discard(device_t dev, off_t pos, off_t len)
615 {
616 	struct ld_softc *sc = device_private(dev);
617 	struct buf dbuf, *bp = &dbuf;
618 	int error = 0;
619 
620 	KASSERT(len <= INT_MAX);
621 
622 	if (sc->sc_discard == NULL)
623 		return (ENODEV);
624 
625 	if ((sc->sc_flags & LDF_MPSAFE) == 0)
626 		KERNEL_LOCK(1, curlwp);
627 
628 	buf_init(bp);
629 	bp->b_vp = NULL;
630 	bp->b_data = NULL;
631 	bp->b_bufsize = 0;
632 	bp->b_rawblkno = pos / sc->sc_secsize;
633 	bp->b_bcount = len;
634 	bp->b_flags = B_WRITE;
635 	bp->b_cflags = BC_BUSY;
636 
637 	error = (*sc->sc_discard)(sc, bp);
638 	if (error == 0)
639 		error = biowait(bp);
640 
641 	buf_destroy(bp);
642 
643 	if ((sc->sc_flags & LDF_MPSAFE) == 0)
644 		KERNEL_UNLOCK_ONE(curlwp);
645 
646 	return error;
647 }
648 
649 void
650 lddiscardend(struct ld_softc *sc, struct buf *bp)
651 {
652 
653 	if (bp->b_error)
654 		bp->b_resid = bp->b_bcount;
655 	biodone(bp);
656 }
657 
658 static int
659 lddiscard(dev_t dev, off_t pos, off_t len)
660 {
661 	struct ld_softc *sc;
662 	struct dk_softc *dksc;
663 	int unit;
664 
665 	unit = DISKUNIT(dev);
666 	sc = device_lookup_private(&ld_cd, unit);
667 	dksc = &sc->sc_dksc;
668 
669 	return dk_discard(dksc, dev, pos, len);
670 }
671 
672 MODULE(MODULE_CLASS_DRIVER, ld, "dk_subr");
673 
674 #ifdef _MODULE
675 CFDRIVER_DECL(ld, DV_DISK, NULL);
676 #endif
677 
678 static int
679 ld_modcmd(modcmd_t cmd, void *opaque)
680 {
681 #ifdef _MODULE
682 	devmajor_t bmajor, cmajor;
683 #endif
684 	int error = 0;
685 
686 #ifdef _MODULE
687 	switch (cmd) {
688 	case MODULE_CMD_INIT:
689 		bmajor = cmajor = -1;
690 		error = devsw_attach(ld_cd.cd_name, &ld_bdevsw, &bmajor,
691 		    &ld_cdevsw, &cmajor);
692 		if (error)
693 			break;
694 		error = config_cfdriver_attach(&ld_cd);
695 		break;
696 	case MODULE_CMD_FINI:
697 		error = config_cfdriver_detach(&ld_cd);
698 		if (error)
699 			break;
700 		devsw_detach(&ld_bdevsw, &ld_cdevsw);
701 		break;
702 	default:
703 		error = ENOTTY;
704 		break;
705 	}
706 #endif
707 
708 	return error;
709 }
710