kern_conf.c revision 244584
1/*-
2 * Copyright (c) 1999-2002 Poul-Henning Kamp
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/kern/kern_conf.c 244584 2012-12-22 13:33:28Z jh $");
29
30#include <sys/param.h>
31#include <sys/kernel.h>
32#include <sys/systm.h>
33#include <sys/bus.h>
34#include <sys/bio.h>
35#include <sys/lock.h>
36#include <sys/mutex.h>
37#include <sys/module.h>
38#include <sys/malloc.h>
39#include <sys/conf.h>
40#include <sys/vnode.h>
41#include <sys/queue.h>
42#include <sys/poll.h>
43#include <sys/sx.h>
44#include <sys/ctype.h>
45#include <sys/ucred.h>
46#include <sys/taskqueue.h>
47#include <machine/stdarg.h>
48
49#include <fs/devfs/devfs_int.h>
50#include <vm/vm.h>
51
52static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage");
53
54struct mtx devmtx;
55static void destroy_devl(struct cdev *dev);
56static int destroy_dev_sched_cbl(struct cdev *dev,
57    void (*cb)(void *), void *arg);
58static void destroy_dev_tq(void *ctx, int pending);
59static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw,
60    int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
61    va_list ap);
62
63static struct cdev_priv_list cdevp_free_list =
64    TAILQ_HEAD_INITIALIZER(cdevp_free_list);
65static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list =
66    SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list);
67
68void
69dev_lock(void)
70{
71
72	mtx_lock(&devmtx);
73}
74
75/*
76 * Free all the memory collected while the cdev mutex was
77 * locked. Since devmtx is after the system map mutex, free() cannot
78 * be called immediately and is postponed until cdev mutex can be
79 * dropped.
80 */
81static void
82dev_unlock_and_free(void)
83{
84	struct cdev_priv_list cdp_free;
85	struct free_cdevsw csw_free;
86	struct cdev_priv *cdp;
87	struct cdevsw *csw;
88
89	mtx_assert(&devmtx, MA_OWNED);
90
91	/*
92	 * Make the local copy of the list heads while the dev_mtx is
93	 * held. Free it later.
94	 */
95	TAILQ_INIT(&cdp_free);
96	TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list);
97	csw_free = cdevsw_gt_post_list;
98	SLIST_INIT(&cdevsw_gt_post_list);
99
100	mtx_unlock(&devmtx);
101
102	while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) {
103		TAILQ_REMOVE(&cdp_free, cdp, cdp_list);
104		devfs_free(&cdp->cdp_c);
105	}
106	while ((csw = SLIST_FIRST(&csw_free)) != NULL) {
107		SLIST_REMOVE_HEAD(&csw_free, d_postfree_list);
108		free(csw, M_DEVT);
109	}
110}
111
112static void
113dev_free_devlocked(struct cdev *cdev)
114{
115	struct cdev_priv *cdp;
116
117	mtx_assert(&devmtx, MA_OWNED);
118	cdp = cdev2priv(cdev);
119	TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list);
120}
121
122static void
123cdevsw_free_devlocked(struct cdevsw *csw)
124{
125
126	mtx_assert(&devmtx, MA_OWNED);
127	SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
128}
129
130void
131dev_unlock(void)
132{
133
134	mtx_unlock(&devmtx);
135}
136
137void
138dev_ref(struct cdev *dev)
139{
140
141	mtx_assert(&devmtx, MA_NOTOWNED);
142	mtx_lock(&devmtx);
143	dev->si_refcount++;
144	mtx_unlock(&devmtx);
145}
146
147void
148dev_refl(struct cdev *dev)
149{
150
151	mtx_assert(&devmtx, MA_OWNED);
152	dev->si_refcount++;
153}
154
155void
156dev_rel(struct cdev *dev)
157{
158	int flag = 0;
159
160	mtx_assert(&devmtx, MA_NOTOWNED);
161	dev_lock();
162	dev->si_refcount--;
163	KASSERT(dev->si_refcount >= 0,
164	    ("dev_rel(%s) gave negative count", devtoname(dev)));
165#if 0
166	if (dev->si_usecount == 0 &&
167	    (dev->si_flags & SI_CHEAPCLONE) && (dev->si_flags & SI_NAMED))
168		;
169	else
170#endif
171	if (dev->si_devsw == NULL && dev->si_refcount == 0) {
172		LIST_REMOVE(dev, si_list);
173		flag = 1;
174	}
175	dev_unlock();
176	if (flag)
177		devfs_free(dev);
178}
179
180struct cdevsw *
181dev_refthread(struct cdev *dev, int *ref)
182{
183	struct cdevsw *csw;
184	struct cdev_priv *cdp;
185
186	mtx_assert(&devmtx, MA_NOTOWNED);
187	if ((dev->si_flags & SI_ETERNAL) != 0) {
188		*ref = 0;
189		return (dev->si_devsw);
190	}
191	dev_lock();
192	csw = dev->si_devsw;
193	if (csw != NULL) {
194		cdp = cdev2priv(dev);
195		if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0)
196			dev->si_threadcount++;
197		else
198			csw = NULL;
199	}
200	dev_unlock();
201	*ref = 1;
202	return (csw);
203}
204
205struct cdevsw *
206devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref)
207{
208	struct cdevsw *csw;
209	struct cdev_priv *cdp;
210	struct cdev *dev;
211
212	mtx_assert(&devmtx, MA_NOTOWNED);
213	if ((vp->v_vflag & VV_ETERNALDEV) != 0) {
214		dev = vp->v_rdev;
215		if (dev == NULL)
216			return (NULL);
217		KASSERT((dev->si_flags & SI_ETERNAL) != 0,
218		    ("Not eternal cdev"));
219		*ref = 0;
220		csw = dev->si_devsw;
221		KASSERT(csw != NULL, ("Eternal cdev is destroyed"));
222		*devp = dev;
223		return (csw);
224	}
225
226	csw = NULL;
227	dev_lock();
228	dev = vp->v_rdev;
229	if (dev == NULL) {
230		dev_unlock();
231		return (NULL);
232	}
233	cdp = cdev2priv(dev);
234	if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
235		csw = dev->si_devsw;
236		if (csw != NULL)
237			dev->si_threadcount++;
238	}
239	dev_unlock();
240	if (csw != NULL) {
241		*devp = dev;
242		*ref = 1;
243	}
244	return (csw);
245}
246
247void
248dev_relthread(struct cdev *dev, int ref)
249{
250
251	mtx_assert(&devmtx, MA_NOTOWNED);
252	if (!ref)
253		return;
254	dev_lock();
255	KASSERT(dev->si_threadcount > 0,
256	    ("%s threadcount is wrong", dev->si_name));
257	dev->si_threadcount--;
258	dev_unlock();
259}
260
261int
262nullop(void)
263{
264
265	return (0);
266}
267
268int
269eopnotsupp(void)
270{
271
272	return (EOPNOTSUPP);
273}
274
275static int
276enxio(void)
277{
278	return (ENXIO);
279}
280
281static int
282enodev(void)
283{
284	return (ENODEV);
285}
286
287/* Define a dead_cdevsw for use when devices leave unexpectedly. */
288
289#define dead_open	(d_open_t *)enxio
290#define dead_close	(d_close_t *)enxio
291#define dead_read	(d_read_t *)enxio
292#define dead_write	(d_write_t *)enxio
293#define dead_ioctl	(d_ioctl_t *)enxio
294#define dead_poll	(d_poll_t *)enodev
295#define dead_mmap	(d_mmap_t *)enodev
296
297static void
298dead_strategy(struct bio *bp)
299{
300
301	biofinish(bp, NULL, ENXIO);
302}
303
304#define dead_dump	(dumper_t *)enxio
305#define dead_kqfilter	(d_kqfilter_t *)enxio
306#define dead_mmap_single (d_mmap_single_t *)enodev
307
308static struct cdevsw dead_cdevsw = {
309	.d_version =	D_VERSION,
310	.d_open =	dead_open,
311	.d_close =	dead_close,
312	.d_read =	dead_read,
313	.d_write =	dead_write,
314	.d_ioctl =	dead_ioctl,
315	.d_poll =	dead_poll,
316	.d_mmap =	dead_mmap,
317	.d_strategy =	dead_strategy,
318	.d_name =	"dead",
319	.d_dump =	dead_dump,
320	.d_kqfilter =	dead_kqfilter,
321	.d_mmap_single = dead_mmap_single
322};
323
324/* Default methods if driver does not specify method */
325
326#define null_open	(d_open_t *)nullop
327#define null_close	(d_close_t *)nullop
328#define no_read		(d_read_t *)enodev
329#define no_write	(d_write_t *)enodev
330#define no_ioctl	(d_ioctl_t *)enodev
331#define no_mmap		(d_mmap_t *)enodev
332#define no_kqfilter	(d_kqfilter_t *)enodev
333#define no_mmap_single	(d_mmap_single_t *)enodev
334
335static void
336no_strategy(struct bio *bp)
337{
338
339	biofinish(bp, NULL, ENODEV);
340}
341
342static int
343no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
344{
345
346	return (poll_no_poll(events));
347}
348
349#define no_dump		(dumper_t *)enodev
350
351static int
352giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
353{
354	struct cdevsw *dsw;
355	int ref, retval;
356
357	dsw = dev_refthread(dev, &ref);
358	if (dsw == NULL)
359		return (ENXIO);
360	mtx_lock(&Giant);
361	retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
362	mtx_unlock(&Giant);
363	dev_relthread(dev, ref);
364	return (retval);
365}
366
367static int
368giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
369{
370	struct cdevsw *dsw;
371	int ref, retval;
372
373	dsw = dev_refthread(dev, &ref);
374	if (dsw == NULL)
375		return (ENXIO);
376	mtx_lock(&Giant);
377	retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
378	mtx_unlock(&Giant);
379	dev_relthread(dev, ref);
380	return (retval);
381}
382
383static int
384giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
385{
386	struct cdevsw *dsw;
387	int ref, retval;
388
389	dsw = dev_refthread(dev, &ref);
390	if (dsw == NULL)
391		return (ENXIO);
392	mtx_lock(&Giant);
393	retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
394	mtx_unlock(&Giant);
395	dev_relthread(dev, ref);
396	return (retval);
397}
398
399static void
400giant_strategy(struct bio *bp)
401{
402	struct cdevsw *dsw;
403	struct cdev *dev;
404	int ref;
405
406	dev = bp->bio_dev;
407	dsw = dev_refthread(dev, &ref);
408	if (dsw == NULL) {
409		biofinish(bp, NULL, ENXIO);
410		return;
411	}
412	mtx_lock(&Giant);
413	dsw->d_gianttrick->d_strategy(bp);
414	mtx_unlock(&Giant);
415	dev_relthread(dev, ref);
416}
417
418static int
419giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
420{
421	struct cdevsw *dsw;
422	int ref, retval;
423
424	dsw = dev_refthread(dev, &ref);
425	if (dsw == NULL)
426		return (ENXIO);
427	mtx_lock(&Giant);
428	retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
429	mtx_unlock(&Giant);
430	dev_relthread(dev, ref);
431	return (retval);
432}
433
434static int
435giant_read(struct cdev *dev, struct uio *uio, int ioflag)
436{
437	struct cdevsw *dsw;
438	int ref, retval;
439
440	dsw = dev_refthread(dev, &ref);
441	if (dsw == NULL)
442		return (ENXIO);
443	mtx_lock(&Giant);
444	retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
445	mtx_unlock(&Giant);
446	dev_relthread(dev, ref);
447	return (retval);
448}
449
450static int
451giant_write(struct cdev *dev, struct uio *uio, int ioflag)
452{
453	struct cdevsw *dsw;
454	int ref, retval;
455
456	dsw = dev_refthread(dev, &ref);
457	if (dsw == NULL)
458		return (ENXIO);
459	mtx_lock(&Giant);
460	retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
461	mtx_unlock(&Giant);
462	dev_relthread(dev, ref);
463	return (retval);
464}
465
466static int
467giant_poll(struct cdev *dev, int events, struct thread *td)
468{
469	struct cdevsw *dsw;
470	int ref, retval;
471
472	dsw = dev_refthread(dev, &ref);
473	if (dsw == NULL)
474		return (ENXIO);
475	mtx_lock(&Giant);
476	retval = dsw->d_gianttrick->d_poll(dev, events, td);
477	mtx_unlock(&Giant);
478	dev_relthread(dev, ref);
479	return (retval);
480}
481
482static int
483giant_kqfilter(struct cdev *dev, struct knote *kn)
484{
485	struct cdevsw *dsw;
486	int ref, retval;
487
488	dsw = dev_refthread(dev, &ref);
489	if (dsw == NULL)
490		return (ENXIO);
491	mtx_lock(&Giant);
492	retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
493	mtx_unlock(&Giant);
494	dev_relthread(dev, ref);
495	return (retval);
496}
497
498static int
499giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot,
500    vm_memattr_t *memattr)
501{
502	struct cdevsw *dsw;
503	int ref, retval;
504
505	dsw = dev_refthread(dev, &ref);
506	if (dsw == NULL)
507		return (ENXIO);
508	mtx_lock(&Giant);
509	retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot,
510	    memattr);
511	mtx_unlock(&Giant);
512	dev_relthread(dev, ref);
513	return (retval);
514}
515
516static int
517giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size,
518    vm_object_t *object, int nprot)
519{
520	struct cdevsw *dsw;
521	int ref, retval;
522
523	dsw = dev_refthread(dev, &ref);
524	if (dsw == NULL)
525		return (ENXIO);
526	mtx_lock(&Giant);
527	retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object,
528	    nprot);
529	mtx_unlock(&Giant);
530	dev_relthread(dev, ref);
531	return (retval);
532}
533
534static void
535notify(struct cdev *dev, const char *ev, int flags)
536{
537	static const char prefix[] = "cdev=";
538	char *data;
539	int namelen, mflags;
540
541	if (cold)
542		return;
543	mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
544	namelen = strlen(dev->si_name);
545	data = malloc(namelen + sizeof(prefix), M_TEMP, mflags);
546	if (data == NULL)
547		return;
548	memcpy(data, prefix, sizeof(prefix) - 1);
549	memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1);
550	devctl_notify_f("DEVFS", "CDEV", ev, data, mflags);
551	free(data, M_TEMP);
552}
553
554static void
555notify_create(struct cdev *dev, int flags)
556{
557
558	notify(dev, "CREATE", flags);
559}
560
561static void
562notify_destroy(struct cdev *dev)
563{
564
565	notify(dev, "DESTROY", MAKEDEV_WAITOK);
566}
567
568static struct cdev *
569newdev(struct cdevsw *csw, int unit, struct cdev *si)
570{
571	struct cdev *si2;
572
573	mtx_assert(&devmtx, MA_OWNED);
574	if (csw->d_flags & D_NEEDMINOR) {
575		/* We may want to return an existing device */
576		LIST_FOREACH(si2, &csw->d_devs, si_list) {
577			if (dev2unit(si2) == unit) {
578				dev_free_devlocked(si);
579				return (si2);
580			}
581		}
582	}
583	si->si_drv0 = unit;
584	si->si_devsw = csw;
585	LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
586	return (si);
587}
588
589static void
590fini_cdevsw(struct cdevsw *devsw)
591{
592	struct cdevsw *gt;
593
594	if (devsw->d_gianttrick != NULL) {
595		gt = devsw->d_gianttrick;
596		memcpy(devsw, gt, sizeof *devsw);
597		cdevsw_free_devlocked(gt);
598		devsw->d_gianttrick = NULL;
599	}
600	devsw->d_flags &= ~D_INIT;
601}
602
603static int
604prep_cdevsw(struct cdevsw *devsw, int flags)
605{
606	struct cdevsw *dsw2;
607
608	mtx_assert(&devmtx, MA_OWNED);
609	if (devsw->d_flags & D_INIT)
610		return (0);
611	if (devsw->d_flags & D_NEEDGIANT) {
612		dev_unlock();
613		dsw2 = malloc(sizeof *dsw2, M_DEVT,
614		     (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
615		dev_lock();
616		if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
617			return (ENOMEM);
618	} else
619		dsw2 = NULL;
620	if (devsw->d_flags & D_INIT) {
621		if (dsw2 != NULL)
622			cdevsw_free_devlocked(dsw2);
623		return (0);
624	}
625
626	if (devsw->d_version != D_VERSION_03) {
627		printf(
628		    "WARNING: Device driver \"%s\" has wrong version %s\n",
629		    devsw->d_name == NULL ? "???" : devsw->d_name,
630		    "and is disabled.  Recompile KLD module.");
631		devsw->d_open = dead_open;
632		devsw->d_close = dead_close;
633		devsw->d_read = dead_read;
634		devsw->d_write = dead_write;
635		devsw->d_ioctl = dead_ioctl;
636		devsw->d_poll = dead_poll;
637		devsw->d_mmap = dead_mmap;
638		devsw->d_mmap_single = dead_mmap_single;
639		devsw->d_strategy = dead_strategy;
640		devsw->d_dump = dead_dump;
641		devsw->d_kqfilter = dead_kqfilter;
642	}
643
644	if (devsw->d_flags & D_NEEDGIANT) {
645		if (devsw->d_gianttrick == NULL) {
646			memcpy(dsw2, devsw, sizeof *dsw2);
647			devsw->d_gianttrick = dsw2;
648			dsw2 = NULL;
649		}
650	}
651
652#define FIXUP(member, noop, giant) 				\
653	do {							\
654		if (devsw->member == NULL) {			\
655			devsw->member = noop;			\
656		} else if (devsw->d_flags & D_NEEDGIANT)	\
657			devsw->member = giant;			\
658		}						\
659	while (0)
660
661	FIXUP(d_open,		null_open,	giant_open);
662	FIXUP(d_fdopen,		NULL,		giant_fdopen);
663	FIXUP(d_close,		null_close,	giant_close);
664	FIXUP(d_read,		no_read,	giant_read);
665	FIXUP(d_write,		no_write,	giant_write);
666	FIXUP(d_ioctl,		no_ioctl,	giant_ioctl);
667	FIXUP(d_poll,		no_poll,	giant_poll);
668	FIXUP(d_mmap,		no_mmap,	giant_mmap);
669	FIXUP(d_strategy,	no_strategy,	giant_strategy);
670	FIXUP(d_kqfilter,	no_kqfilter,	giant_kqfilter);
671	FIXUP(d_mmap_single,	no_mmap_single,	giant_mmap_single);
672
673	if (devsw->d_dump == NULL)	devsw->d_dump = no_dump;
674
675	LIST_INIT(&devsw->d_devs);
676
677	devsw->d_flags |= D_INIT;
678
679	if (dsw2 != NULL)
680		cdevsw_free_devlocked(dsw2);
681	return (0);
682}
683
684static int
685prep_devname(struct cdev *dev, const char *fmt, va_list ap)
686{
687	int len;
688	char *from, *q, *s, *to;
689
690	mtx_assert(&devmtx, MA_OWNED);
691
692	len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap);
693	if (len > sizeof(dev->si_name) - 1)
694		return (ENAMETOOLONG);
695
696	/* Strip leading slashes. */
697	for (from = dev->si_name; *from == '/'; from++)
698		;
699
700	for (to = dev->si_name; *from != '\0'; from++, to++) {
701		/*
702		 * Spaces and double quotation marks cause
703		 * problems for the devctl(4) protocol.
704		 * Reject names containing those characters.
705		 */
706		if (isspace(*from) || *from == '"')
707			return (EINVAL);
708		/* Treat multiple sequential slashes as single. */
709		while (from[0] == '/' && from[1] == '/')
710			from++;
711		/* Trailing slash is considered invalid. */
712		if (from[0] == '/' && from[1] == '\0')
713			return (EINVAL);
714		*to = *from;
715	}
716	*to = '\0';
717
718	if (dev->si_name[0] == '\0')
719		return (EINVAL);
720
721	/* Disallow "." and ".." components. */
722	for (s = dev->si_name;;) {
723		for (q = s; *q != '/' && *q != '\0'; q++)
724			;
725		if (q - s == 1 && s[0] == '.')
726			return (EINVAL);
727		if (q - s == 2 && s[0] == '.' && s[1] == '.')
728			return (EINVAL);
729		if (*q != '/')
730			break;
731		s = q + 1;
732	}
733
734	if (devfs_dev_exists(dev->si_name) != 0)
735		return (EEXIST);
736
737	return (0);
738}
739
740static int
741make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
742    struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
743    va_list ap)
744{
745	struct cdev *dev, *dev_new;
746	int res;
747
748	KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
749	    ("make_dev_credv: both WAITOK and NOWAIT specified"));
750	dev_new = devfs_alloc(flags);
751	if (dev_new == NULL)
752		return (ENOMEM);
753	dev_lock();
754	res = prep_cdevsw(devsw, flags);
755	if (res != 0) {
756		dev_unlock();
757		devfs_free(dev_new);
758		return (res);
759	}
760	dev = newdev(devsw, unit, dev_new);
761	if ((dev->si_flags & SI_NAMED) == 0) {
762		res = prep_devname(dev, fmt, ap);
763		if (res != 0) {
764			if ((flags & MAKEDEV_CHECKNAME) == 0) {
765				panic(
766			"make_dev_credv: bad si_name (error=%d, si_name=%s)",
767				    res, dev->si_name);
768			}
769			if (dev == dev_new) {
770				LIST_REMOVE(dev, si_list);
771				dev_unlock();
772				devfs_free(dev);
773			} else
774				dev_unlock();
775			return (res);
776		}
777	}
778	if (flags & MAKEDEV_REF)
779		dev_refl(dev);
780	if (flags & MAKEDEV_ETERNAL)
781		dev->si_flags |= SI_ETERNAL;
782	if (dev->si_flags & SI_CHEAPCLONE &&
783	    dev->si_flags & SI_NAMED) {
784		/*
785		 * This is allowed as it removes races and generally
786		 * simplifies cloning devices.
787		 * XXX: still ??
788		 */
789		dev_unlock_and_free();
790		*dres = dev;
791		return (0);
792	}
793	KASSERT(!(dev->si_flags & SI_NAMED),
794	    ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
795	    devsw->d_name, dev2unit(dev), devtoname(dev)));
796	dev->si_flags |= SI_NAMED;
797	if (cr != NULL)
798		dev->si_cred = crhold(cr);
799	dev->si_uid = uid;
800	dev->si_gid = gid;
801	dev->si_mode = mode;
802
803	devfs_create(dev);
804	clean_unrhdrl(devfs_inos);
805	dev_unlock_and_free();
806
807	notify_create(dev, flags);
808
809	*dres = dev;
810	return (0);
811}
812
813struct cdev *
814make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
815    const char *fmt, ...)
816{
817	struct cdev *dev;
818	va_list ap;
819	int res;
820
821	va_start(ap, fmt);
822	res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
823	    ap);
824	va_end(ap);
825	KASSERT(res == 0 && dev != NULL,
826	    ("make_dev: failed make_dev_credv (error=%d)", res));
827	return (dev);
828}
829
830struct cdev *
831make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
832    gid_t gid, int mode, const char *fmt, ...)
833{
834	struct cdev *dev;
835	va_list ap;
836	int res;
837
838	va_start(ap, fmt);
839	res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
840	va_end(ap);
841
842	KASSERT(res == 0 && dev != NULL,
843	    ("make_dev_cred: failed make_dev_credv (error=%d)", res));
844	return (dev);
845}
846
847struct cdev *
848make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
849    uid_t uid, gid_t gid, int mode, const char *fmt, ...)
850{
851	struct cdev *dev;
852	va_list ap;
853	int res;
854
855	va_start(ap, fmt);
856	res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
857	    fmt, ap);
858	va_end(ap);
859
860	KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
861	    ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
862	    ("make_dev_credf: failed make_dev_credv (error=%d)", res));
863	return (res == 0 ? dev : NULL);
864}
865
866int
867make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw,
868    struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
869{
870	va_list ap;
871	int res;
872
873	va_start(ap, fmt);
874	res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
875	    fmt, ap);
876	va_end(ap);
877
878	KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
879	    ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
880	    ("make_dev_p: failed make_dev_credv (error=%d)", res));
881	return (res);
882}
883
884static void
885dev_dependsl(struct cdev *pdev, struct cdev *cdev)
886{
887
888	cdev->si_parent = pdev;
889	cdev->si_flags |= SI_CHILD;
890	LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
891}
892
893
894void
895dev_depends(struct cdev *pdev, struct cdev *cdev)
896{
897
898	dev_lock();
899	dev_dependsl(pdev, cdev);
900	dev_unlock();
901}
902
903static int
904make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
905    const char *fmt, va_list ap)
906{
907	struct cdev *dev;
908	int error;
909
910	KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL"));
911	KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
912	    ("make_dev_alias_v: both WAITOK and NOWAIT specified"));
913	KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT |
914	    MAKEDEV_CHECKNAME)) == 0,
915	    ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags));
916
917	dev = devfs_alloc(flags);
918	if (dev == NULL)
919		return (ENOMEM);
920	dev_lock();
921	dev->si_flags |= SI_ALIAS;
922	error = prep_devname(dev, fmt, ap);
923	if (error != 0) {
924		if ((flags & MAKEDEV_CHECKNAME) == 0) {
925			panic("make_dev_alias_v: bad si_name "
926			    "(error=%d, si_name=%s)", error, dev->si_name);
927		}
928		dev_unlock();
929		devfs_free(dev);
930		return (error);
931	}
932	dev->si_flags |= SI_NAMED;
933	devfs_create(dev);
934	dev_dependsl(pdev, dev);
935	clean_unrhdrl(devfs_inos);
936	dev_unlock();
937
938	notify_create(dev, flags);
939	*cdev = dev;
940
941	return (0);
942}
943
944struct cdev *
945make_dev_alias(struct cdev *pdev, const char *fmt, ...)
946{
947	struct cdev *dev;
948	va_list ap;
949	int res;
950
951	va_start(ap, fmt);
952	res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
953	va_end(ap);
954
955	KASSERT(res == 0 && dev != NULL,
956	    ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
957	return (dev);
958}
959
960int
961make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
962    const char *fmt, ...)
963{
964	va_list ap;
965	int res;
966
967	va_start(ap, fmt);
968	res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
969	va_end(ap);
970	return (res);
971}
972
973int
974make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
975    struct cdev *old_alias, const char *physpath)
976{
977	char *devfspath;
978	int physpath_len;
979	int max_parentpath_len;
980	int parentpath_len;
981	int devfspathbuf_len;
982	int mflags;
983	int ret;
984
985	*cdev = NULL;
986	devfspath = NULL;
987	physpath_len = strlen(physpath);
988	ret = EINVAL;
989	if (physpath_len == 0)
990		goto out;
991
992	if (strncmp("id1,", physpath, 4) == 0) {
993		physpath += 4;
994		physpath_len -= 4;
995		if (physpath_len == 0)
996			goto out;
997	}
998
999	max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
1000	parentpath_len = strlen(pdev->si_name);
1001	if (max_parentpath_len < parentpath_len) {
1002		if (bootverbose)
1003			printf("WARNING: Unable to alias %s "
1004			    "to %s/%s - path too long\n",
1005			    pdev->si_name, physpath, pdev->si_name);
1006		ret = ENAMETOOLONG;
1007		goto out;
1008	}
1009
1010	mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
1011	devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1;
1012	devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags);
1013	if (devfspath == NULL) {
1014		ret = ENOMEM;
1015		goto out;
1016	}
1017
1018	sprintf(devfspath, "%s/%s", physpath, pdev->si_name);
1019	if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) {
1020		/* Retain the existing alias. */
1021		*cdev = old_alias;
1022		old_alias = NULL;
1023		ret = 0;
1024	} else {
1025		ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1026	}
1027out:
1028	if (old_alias != NULL)
1029		destroy_dev(old_alias);
1030	if (devfspath != NULL)
1031		free(devfspath, M_DEVBUF);
1032	return (ret);
1033}
1034
1035static void
1036destroy_devl(struct cdev *dev)
1037{
1038	struct cdevsw *csw;
1039	struct cdev_privdata *p;
1040
1041	mtx_assert(&devmtx, MA_OWNED);
1042	KASSERT(dev->si_flags & SI_NAMED,
1043	    ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
1044	KASSERT((dev->si_flags & SI_ETERNAL) == 0,
1045	    ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
1046	     dev2unit(dev)));
1047
1048	devfs_destroy(dev);
1049
1050	/* Remove name marking */
1051	dev->si_flags &= ~SI_NAMED;
1052
1053	dev->si_refcount++;	/* Avoid race with dev_rel() */
1054
1055	/* If we are a child, remove us from the parents list */
1056	if (dev->si_flags & SI_CHILD) {
1057		LIST_REMOVE(dev, si_siblings);
1058		dev->si_flags &= ~SI_CHILD;
1059	}
1060
1061	/* Kill our children */
1062	while (!LIST_EMPTY(&dev->si_children))
1063		destroy_devl(LIST_FIRST(&dev->si_children));
1064
1065	/* Remove from clone list */
1066	if (dev->si_flags & SI_CLONELIST) {
1067		LIST_REMOVE(dev, si_clone);
1068		dev->si_flags &= ~SI_CLONELIST;
1069	}
1070
1071	csw = dev->si_devsw;
1072	dev->si_devsw = NULL;	/* already NULL for SI_ALIAS */
1073	while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
1074		csw->d_purge(dev);
1075		msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
1076		if (dev->si_threadcount)
1077			printf("Still %lu threads in %s\n",
1078			    dev->si_threadcount, devtoname(dev));
1079	}
1080	while (dev->si_threadcount != 0) {
1081		/* Use unique dummy wait ident */
1082		msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
1083	}
1084
1085	dev_unlock();
1086	notify_destroy(dev);
1087	mtx_lock(&cdevpriv_mtx);
1088	while ((p = LIST_FIRST(&cdev2priv(dev)->cdp_fdpriv)) != NULL) {
1089		devfs_destroy_cdevpriv(p);
1090		mtx_lock(&cdevpriv_mtx);
1091	}
1092	mtx_unlock(&cdevpriv_mtx);
1093	dev_lock();
1094
1095	dev->si_drv1 = 0;
1096	dev->si_drv2 = 0;
1097	bzero(&dev->__si_u, sizeof(dev->__si_u));
1098
1099	if (!(dev->si_flags & SI_ALIAS)) {
1100		/* Remove from cdevsw list */
1101		LIST_REMOVE(dev, si_list);
1102
1103		/* If cdevsw has no more struct cdev *'s, clean it */
1104		if (LIST_EMPTY(&csw->d_devs)) {
1105			fini_cdevsw(csw);
1106			wakeup(&csw->d_devs);
1107		}
1108	}
1109	dev->si_flags &= ~SI_ALIAS;
1110	dev->si_refcount--;	/* Avoid race with dev_rel() */
1111
1112	if (dev->si_refcount > 0) {
1113		LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1114	} else {
1115		dev_free_devlocked(dev);
1116	}
1117}
1118
1119void
1120destroy_dev(struct cdev *dev)
1121{
1122
1123	WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1124	dev_lock();
1125	destroy_devl(dev);
1126	dev_unlock_and_free();
1127}
1128
1129const char *
1130devtoname(struct cdev *dev)
1131{
1132
1133	return (dev->si_name);
1134}
1135
1136int
1137dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1138{
1139	int u, i;
1140
1141	i = strlen(stem);
1142	if (bcmp(stem, name, i) != 0)
1143		return (0);
1144	if (!isdigit(name[i]))
1145		return (0);
1146	u = 0;
1147	if (name[i] == '0' && isdigit(name[i+1]))
1148		return (0);
1149	while (isdigit(name[i])) {
1150		u *= 10;
1151		u += name[i++] - '0';
1152	}
1153	if (u > 0xffffff)
1154		return (0);
1155	*unit = u;
1156	if (namep)
1157		*namep = &name[i];
1158	if (name[i])
1159		return (2);
1160	return (1);
1161}
1162
1163/*
1164 * Helper functions for cloning device drivers.
1165 *
1166 * The objective here is to make it unnecessary for the device drivers to
1167 * use rman or similar to manage their unit number space.  Due to the way
1168 * we do "on-demand" devices, using rman or other "private" methods
1169 * will be very tricky to lock down properly once we lock down this file.
1170 *
1171 * Instead we give the drivers these routines which puts the struct cdev *'s
1172 * that are to be managed on their own list, and gives the driver the ability
1173 * to ask for the first free unit number or a given specified unit number.
1174 *
1175 * In addition these routines support paired devices (pty, nmdm and similar)
1176 * by respecting a number of "flag" bits in the minor number.
1177 *
1178 */
1179
1180struct clonedevs {
1181	LIST_HEAD(,cdev)	head;
1182};
1183
1184void
1185clone_setup(struct clonedevs **cdp)
1186{
1187
1188	*cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1189	LIST_INIT(&(*cdp)->head);
1190}
1191
1192int
1193clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1194    struct cdev **dp, int extra)
1195{
1196	struct clonedevs *cd;
1197	struct cdev *dev, *ndev, *dl, *de;
1198	int unit, low, u;
1199
1200	KASSERT(*cdp != NULL,
1201	    ("clone_setup() not called in driver \"%s\"", csw->d_name));
1202	KASSERT(!(extra & CLONE_UNITMASK),
1203	    ("Illegal extra bits (0x%x) in clone_create", extra));
1204	KASSERT(*up <= CLONE_UNITMASK,
1205	    ("Too high unit (0x%x) in clone_create", *up));
1206	KASSERT(csw->d_flags & D_NEEDMINOR,
1207	    ("clone_create() on cdevsw without minor numbers"));
1208
1209
1210	/*
1211	 * Search the list for a lot of things in one go:
1212	 *   A preexisting match is returned immediately.
1213	 *   The lowest free unit number if we are passed -1, and the place
1214	 *	 in the list where we should insert that new element.
1215	 *   The place to insert a specified unit number, if applicable
1216	 *       the end of the list.
1217	 */
1218	unit = *up;
1219	ndev = devfs_alloc(MAKEDEV_WAITOK);
1220	dev_lock();
1221	prep_cdevsw(csw, MAKEDEV_WAITOK);
1222	low = extra;
1223	de = dl = NULL;
1224	cd = *cdp;
1225	LIST_FOREACH(dev, &cd->head, si_clone) {
1226		KASSERT(dev->si_flags & SI_CLONELIST,
1227		    ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1228		u = dev2unit(dev);
1229		if (u == (unit | extra)) {
1230			*dp = dev;
1231			dev_unlock();
1232			devfs_free(ndev);
1233			return (0);
1234		}
1235		if (unit == -1 && u == low) {
1236			low++;
1237			de = dev;
1238			continue;
1239		} else if (u < (unit | extra)) {
1240			de = dev;
1241			continue;
1242		} else if (u > (unit | extra)) {
1243			dl = dev;
1244			break;
1245		}
1246	}
1247	if (unit == -1)
1248		unit = low & CLONE_UNITMASK;
1249	dev = newdev(csw, unit | extra, ndev);
1250	if (dev->si_flags & SI_CLONELIST) {
1251		printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1252		printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1253		LIST_FOREACH(dev, &cd->head, si_clone) {
1254			printf("\t%p %s\n", dev, dev->si_name);
1255		}
1256		panic("foo");
1257	}
1258	KASSERT(!(dev->si_flags & SI_CLONELIST),
1259	    ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1260	if (dl != NULL)
1261		LIST_INSERT_BEFORE(dl, dev, si_clone);
1262	else if (de != NULL)
1263		LIST_INSERT_AFTER(de, dev, si_clone);
1264	else
1265		LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1266	dev->si_flags |= SI_CLONELIST;
1267	*up = unit;
1268	dev_unlock_and_free();
1269	return (1);
1270}
1271
1272/*
1273 * Kill everything still on the list.  The driver should already have
1274 * disposed of any softc hung of the struct cdev *'s at this time.
1275 */
1276void
1277clone_cleanup(struct clonedevs **cdp)
1278{
1279	struct cdev *dev;
1280	struct cdev_priv *cp;
1281	struct clonedevs *cd;
1282
1283	cd = *cdp;
1284	if (cd == NULL)
1285		return;
1286	dev_lock();
1287	while (!LIST_EMPTY(&cd->head)) {
1288		dev = LIST_FIRST(&cd->head);
1289		LIST_REMOVE(dev, si_clone);
1290		KASSERT(dev->si_flags & SI_CLONELIST,
1291		    ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1292		dev->si_flags &= ~SI_CLONELIST;
1293		cp = cdev2priv(dev);
1294		if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1295			cp->cdp_flags |= CDP_SCHED_DTR;
1296			KASSERT(dev->si_flags & SI_NAMED,
1297				("Driver has goofed in cloning underways udev %x unit %x", dev2udev(dev), dev2unit(dev)));
1298			destroy_devl(dev);
1299		}
1300	}
1301	dev_unlock_and_free();
1302	free(cd, M_DEVBUF);
1303	*cdp = NULL;
1304}
1305
1306static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1307	TAILQ_HEAD_INITIALIZER(dev_ddtr);
1308static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL);
1309
1310static void
1311destroy_dev_tq(void *ctx, int pending)
1312{
1313	struct cdev_priv *cp;
1314	struct cdev *dev;
1315	void (*cb)(void *);
1316	void *cb_arg;
1317
1318	dev_lock();
1319	while (!TAILQ_EMPTY(&dev_ddtr)) {
1320		cp = TAILQ_FIRST(&dev_ddtr);
1321		dev = &cp->cdp_c;
1322		KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1323		    ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1324		TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list);
1325		cb = cp->cdp_dtr_cb;
1326		cb_arg = cp->cdp_dtr_cb_arg;
1327		destroy_devl(dev);
1328		dev_unlock_and_free();
1329		dev_rel(dev);
1330		if (cb != NULL)
1331			cb(cb_arg);
1332		dev_lock();
1333	}
1334	dev_unlock();
1335}
1336
1337/*
1338 * devmtx shall be locked on entry. devmtx will be unlocked after
1339 * function return.
1340 */
1341static int
1342destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1343{
1344	struct cdev_priv *cp;
1345
1346	mtx_assert(&devmtx, MA_OWNED);
1347	cp = cdev2priv(dev);
1348	if (cp->cdp_flags & CDP_SCHED_DTR) {
1349		dev_unlock();
1350		return (0);
1351	}
1352	dev_refl(dev);
1353	cp->cdp_flags |= CDP_SCHED_DTR;
1354	cp->cdp_dtr_cb = cb;
1355	cp->cdp_dtr_cb_arg = arg;
1356	TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1357	dev_unlock();
1358	taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1359	return (1);
1360}
1361
1362int
1363destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1364{
1365
1366	dev_lock();
1367	return (destroy_dev_sched_cbl(dev, cb, arg));
1368}
1369
1370int
1371destroy_dev_sched(struct cdev *dev)
1372{
1373
1374	return (destroy_dev_sched_cb(dev, NULL, NULL));
1375}
1376
1377void
1378destroy_dev_drain(struct cdevsw *csw)
1379{
1380
1381	dev_lock();
1382	while (!LIST_EMPTY(&csw->d_devs)) {
1383		msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1384	}
1385	dev_unlock();
1386}
1387
1388void
1389drain_dev_clone_events(void)
1390{
1391
1392	sx_xlock(&clone_drain_lock);
1393	sx_xunlock(&clone_drain_lock);
1394}
1395
1396#include "opt_ddb.h"
1397#ifdef DDB
1398#include <sys/kernel.h>
1399
1400#include <ddb/ddb.h>
1401
1402DB_SHOW_COMMAND(cdev, db_show_cdev)
1403{
1404	struct cdev_priv *cdp;
1405	struct cdev *dev;
1406	u_int flags;
1407	char buf[512];
1408
1409	if (!have_addr) {
1410		TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1411			dev = &cdp->cdp_c;
1412			db_printf("%s %p\n", dev->si_name, dev);
1413			if (db_pager_quit)
1414				break;
1415		}
1416		return;
1417	}
1418
1419	dev = (struct cdev *)addr;
1420	cdp = cdev2priv(dev);
1421	db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n",
1422	    dev->si_name, dev->si_refcount, dev->si_usecount,
1423	    dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first);
1424	db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n",
1425	    dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2);
1426	flags = dev->si_flags;
1427#define	SI_FLAG(flag)	do {						\
1428	if (flags & (flag)) {						\
1429		if (buf[0] != '\0')					\
1430			strlcat(buf, ", ", sizeof(buf));		\
1431		strlcat(buf, (#flag) + 3, sizeof(buf));			\
1432		flags &= ~(flag);					\
1433	}								\
1434} while (0)
1435	buf[0] = '\0';
1436	SI_FLAG(SI_ETERNAL);
1437	SI_FLAG(SI_ALIAS);
1438	SI_FLAG(SI_NAMED);
1439	SI_FLAG(SI_CHEAPCLONE);
1440	SI_FLAG(SI_CHILD);
1441	SI_FLAG(SI_DUMPDEV);
1442	SI_FLAG(SI_CLONELIST);
1443	db_printf("si_flags %s\n", buf);
1444
1445	flags = cdp->cdp_flags;
1446#define	CDP_FLAG(flag)	do {						\
1447	if (flags & (flag)) {						\
1448		if (buf[0] != '\0')					\
1449			strlcat(buf, ", ", sizeof(buf));		\
1450		strlcat(buf, (#flag) + 4, sizeof(buf));			\
1451		flags &= ~(flag);					\
1452	}								\
1453} while (0)
1454	buf[0] = '\0';
1455	CDP_FLAG(CDP_ACTIVE);
1456	CDP_FLAG(CDP_SCHED_DTR);
1457	db_printf("cdp_flags %s\n", buf);
1458}
1459#endif
1460