xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 62a8debe1dc62962e18a1c918def78666141273b)
1 /* $NetBSD: subr_autoconf.c,v 1.203 2010/02/24 22:38:10 dyoung Exp $ */
2 
3 /*
4  * Copyright (c) 1996, 2000 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.NetBSD.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )--
35  */
36 
37 /*
38  * Copyright (c) 1992, 1993
39  *	The Regents of the University of California.  All rights reserved.
40  *
41  * This software was developed by the Computer Systems Engineering group
42  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
43  * contributed to Berkeley.
44  *
45  * All advertising materials mentioning features or use of this software
46  * must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Lawrence Berkeley Laboratories.
49  *
50  * Redistribution and use in source and binary forms, with or without
51  * modification, are permitted provided that the following conditions
52  * are met:
53  * 1. Redistributions of source code must retain the above copyright
54  *    notice, this list of conditions and the following disclaimer.
55  * 2. Redistributions in binary form must reproduce the above copyright
56  *    notice, this list of conditions and the following disclaimer in the
57  *    documentation and/or other materials provided with the distribution.
58  * 3. Neither the name of the University nor the names of its contributors
59  *    may be used to endorse or promote products derived from this software
60  *    without specific prior written permission.
61  *
62  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
63  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
64  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
65  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
66  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
67  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
68  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
69  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
70  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
71  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72  * SUCH DAMAGE.
73  *
74  * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp  (LBL)
75  *
76  *	@(#)subr_autoconf.c	8.3 (Berkeley) 5/17/94
77  */
78 
79 #include <sys/cdefs.h>
80 __KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.203 2010/02/24 22:38:10 dyoung Exp $");
81 
82 #ifdef _KERNEL_OPT
83 #include "opt_ddb.h"
84 #endif
85 
86 #include <sys/param.h>
87 #include <sys/device.h>
88 #include <sys/disklabel.h>
89 #include <sys/conf.h>
90 #include <sys/kauth.h>
91 #include <sys/malloc.h>
92 #include <sys/kmem.h>
93 #include <sys/systm.h>
94 #include <sys/kernel.h>
95 #include <sys/errno.h>
96 #include <sys/proc.h>
97 #include <sys/reboot.h>
98 #include <sys/kthread.h>
99 #include <sys/buf.h>
100 #include <sys/dirent.h>
101 #include <sys/vnode.h>
102 #include <sys/mount.h>
103 #include <sys/namei.h>
104 #include <sys/unistd.h>
105 #include <sys/fcntl.h>
106 #include <sys/lockf.h>
107 #include <sys/callout.h>
108 #include <sys/devmon.h>
109 #include <sys/cpu.h>
110 #include <sys/sysctl.h>
111 
112 #include <sys/disk.h>
113 
114 #include <machine/limits.h>
115 
116 #if defined(__i386__) && defined(_KERNEL_OPT)
117 #include "opt_splash.h"
118 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
119 #include <dev/splash/splash.h>
120 extern struct splash_progress *splash_progress_state;
121 #endif
122 #endif
123 
124 /*
125  * Autoconfiguration subroutines.
126  */
127 
128 /*
129  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
130  * devices and drivers are found via these tables.
131  */
132 extern struct cfdata cfdata[];
133 extern const short cfroots[];
134 
135 /*
136  * List of all cfdriver structures.  We use this to detect duplicates
137  * when other cfdrivers are loaded.
138  */
139 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
140 extern struct cfdriver * const cfdriver_list_initial[];
141 
142 /*
143  * Initial list of cfattach's.
144  */
145 extern const struct cfattachinit cfattachinit[];
146 
147 /*
148  * List of cfdata tables.  We always have one such list -- the one
149  * built statically when the kernel was configured.
150  */
151 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
152 static struct cftable initcftable;
153 
154 #define	ROOT ((device_t)NULL)
155 
156 struct matchinfo {
157 	cfsubmatch_t fn;
158 	struct	device *parent;
159 	const int *locs;
160 	void	*aux;
161 	struct	cfdata *match;
162 	int	pri;
163 };
164 
165 struct alldevs_foray {
166 	int			af_s;
167 	struct devicelist	af_garbage;
168 };
169 
170 static char *number(char *, int);
171 static void mapply(struct matchinfo *, cfdata_t);
172 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
173 static void config_devdelete(device_t);
174 static void config_devunlink(device_t, struct devicelist *);
175 static void config_makeroom(int, struct cfdriver *);
176 static void config_devlink(device_t);
177 static void config_alldevs_unlock(int);
178 static int config_alldevs_lock(void);
179 static void config_alldevs_enter(struct alldevs_foray *);
180 static void config_alldevs_exit(struct alldevs_foray *);
181 
182 static void config_collect_garbage(struct devicelist *);
183 static void config_dump_garbage(struct devicelist *);
184 
185 static void pmflock_debug(device_t, const char *, int);
186 
187 static device_t deviter_next1(deviter_t *);
188 static void deviter_reinit(deviter_t *);
189 
190 struct deferred_config {
191 	TAILQ_ENTRY(deferred_config) dc_queue;
192 	device_t dc_dev;
193 	void (*dc_func)(device_t);
194 };
195 
196 TAILQ_HEAD(deferred_config_head, deferred_config);
197 
198 struct deferred_config_head deferred_config_queue =
199 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
200 struct deferred_config_head interrupt_config_queue =
201 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
202 int interrupt_config_threads = 8;
203 
204 static void config_process_deferred(struct deferred_config_head *, device_t);
205 
206 /* Hooks to finalize configuration once all real devices have been found. */
207 struct finalize_hook {
208 	TAILQ_ENTRY(finalize_hook) f_list;
209 	int (*f_func)(device_t);
210 	device_t f_dev;
211 };
212 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
213 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
214 static int config_finalize_done;
215 
216 /* list of all devices */
217 static struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
218 static kmutex_t alldevs_mtx;
219 static volatile bool alldevs_garbage = false;
220 static volatile devgen_t alldevs_gen = 1;
221 static volatile int alldevs_nread = 0;
222 static volatile int alldevs_nwrite = 0;
223 
224 static int config_pending;		/* semaphore for mountroot */
225 static kmutex_t config_misc_lock;
226 static kcondvar_t config_misc_cv;
227 
228 static int detachall = 0;
229 
230 #define	STREQ(s1, s2)			\
231 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
232 
233 static bool config_initialized = false;	/* config_init() has been called. */
234 
235 static int config_do_twiddle;
236 static callout_t config_twiddle_ch;
237 
238 static void sysctl_detach_setup(struct sysctllog **);
239 
240 /*
241  * Initialize the autoconfiguration data structures.  Normally this
242  * is done by configure(), but some platforms need to do this very
243  * early (to e.g. initialize the console).
244  */
245 void
246 config_init(void)
247 {
248 	const struct cfattachinit *cfai;
249 	int i, j;
250 
251 	KASSERT(config_initialized == false);
252 
253 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_VM);
254 
255 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
256 	cv_init(&config_misc_cv, "cfgmisc");
257 
258 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
259 
260 	/* allcfdrivers is statically initialized. */
261 	for (i = 0; cfdriver_list_initial[i] != NULL; i++) {
262 		if (config_cfdriver_attach(cfdriver_list_initial[i]) != 0)
263 			panic("configure: duplicate `%s' drivers",
264 			    cfdriver_list_initial[i]->cd_name);
265 	}
266 
267 	for (cfai = &cfattachinit[0]; cfai->cfai_name != NULL; cfai++) {
268 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
269 			if (config_cfattach_attach(cfai->cfai_name,
270 						   cfai->cfai_list[j]) != 0)
271 				panic("configure: duplicate `%s' attachment "
272 				    "of `%s' driver",
273 				    cfai->cfai_list[j]->ca_name,
274 				    cfai->cfai_name);
275 		}
276 	}
277 
278 	initcftable.ct_cfdata = cfdata;
279 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
280 
281 	config_initialized = true;
282 }
283 
284 void
285 config_init_mi(void)
286 {
287 
288 	if (!config_initialized)
289 		config_init();
290 
291 	sysctl_detach_setup(NULL);
292 }
293 
294 void
295 config_deferred(device_t dev)
296 {
297 	config_process_deferred(&deferred_config_queue, dev);
298 	config_process_deferred(&interrupt_config_queue, dev);
299 }
300 
301 static void
302 config_interrupts_thread(void *cookie)
303 {
304 	struct deferred_config *dc;
305 
306 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
307 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
308 		(*dc->dc_func)(dc->dc_dev);
309 		kmem_free(dc, sizeof(*dc));
310 		config_pending_decr();
311 	}
312 	kthread_exit(0);
313 }
314 
315 void
316 config_create_interruptthreads()
317 {
318 	int i;
319 
320 	for (i = 0; i < interrupt_config_threads; i++) {
321 		(void)kthread_create(PRI_NONE, 0, NULL,
322 		    config_interrupts_thread, NULL, NULL, "config");
323 	}
324 }
325 
326 /*
327  * Announce device attach/detach to userland listeners.
328  */
329 static void
330 devmon_report_device(device_t dev, bool isattach)
331 {
332 #if NDRVCTL > 0
333 	prop_dictionary_t ev;
334 	const char *parent;
335 	const char *what;
336 	device_t pdev = device_parent(dev);
337 
338 	ev = prop_dictionary_create();
339 	if (ev == NULL)
340 		return;
341 
342 	what = (isattach ? "device-attach" : "device-detach");
343 	parent = (pdev == NULL ? "root" : device_xname(pdev));
344 	if (!prop_dictionary_set_cstring(ev, "device", device_xname(dev)) ||
345 	    !prop_dictionary_set_cstring(ev, "parent", parent)) {
346 		prop_object_release(ev);
347 		return;
348 	}
349 
350 	devmon_insert(what, ev);
351 #endif
352 }
353 
354 /*
355  * Add a cfdriver to the system.
356  */
357 int
358 config_cfdriver_attach(struct cfdriver *cd)
359 {
360 	struct cfdriver *lcd;
361 
362 	/* Make sure this driver isn't already in the system. */
363 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
364 		if (STREQ(lcd->cd_name, cd->cd_name))
365 			return EEXIST;
366 	}
367 
368 	LIST_INIT(&cd->cd_attach);
369 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
370 
371 	return 0;
372 }
373 
374 /*
375  * Remove a cfdriver from the system.
376  */
377 int
378 config_cfdriver_detach(struct cfdriver *cd)
379 {
380 	struct alldevs_foray af;
381 	int i, rc = 0;
382 
383 	config_alldevs_enter(&af);
384 	/* Make sure there are no active instances. */
385 	for (i = 0; i < cd->cd_ndevs; i++) {
386 		if (cd->cd_devs[i] != NULL) {
387 			rc = EBUSY;
388 			break;
389 		}
390 	}
391 	config_alldevs_exit(&af);
392 
393 	if (rc != 0)
394 		return rc;
395 
396 	/* ...and no attachments loaded. */
397 	if (LIST_EMPTY(&cd->cd_attach) == 0)
398 		return EBUSY;
399 
400 	LIST_REMOVE(cd, cd_list);
401 
402 	KASSERT(cd->cd_devs == NULL);
403 
404 	return 0;
405 }
406 
407 /*
408  * Look up a cfdriver by name.
409  */
410 struct cfdriver *
411 config_cfdriver_lookup(const char *name)
412 {
413 	struct cfdriver *cd;
414 
415 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
416 		if (STREQ(cd->cd_name, name))
417 			return cd;
418 	}
419 
420 	return NULL;
421 }
422 
423 /*
424  * Add a cfattach to the specified driver.
425  */
426 int
427 config_cfattach_attach(const char *driver, struct cfattach *ca)
428 {
429 	struct cfattach *lca;
430 	struct cfdriver *cd;
431 
432 	cd = config_cfdriver_lookup(driver);
433 	if (cd == NULL)
434 		return ESRCH;
435 
436 	/* Make sure this attachment isn't already on this driver. */
437 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
438 		if (STREQ(lca->ca_name, ca->ca_name))
439 			return EEXIST;
440 	}
441 
442 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
443 
444 	return 0;
445 }
446 
447 /*
448  * Remove a cfattach from the specified driver.
449  */
450 int
451 config_cfattach_detach(const char *driver, struct cfattach *ca)
452 {
453 	struct alldevs_foray af;
454 	struct cfdriver *cd;
455 	device_t dev;
456 	int i, rc = 0;
457 
458 	cd = config_cfdriver_lookup(driver);
459 	if (cd == NULL)
460 		return ESRCH;
461 
462 	config_alldevs_enter(&af);
463 	/* Make sure there are no active instances. */
464 	for (i = 0; i < cd->cd_ndevs; i++) {
465 		if ((dev = cd->cd_devs[i]) == NULL)
466 			continue;
467 		if (dev->dv_cfattach == ca) {
468 			rc = EBUSY;
469 			break;
470 		}
471 	}
472 	config_alldevs_exit(&af);
473 
474 	if (rc != 0)
475 		return rc;
476 
477 	LIST_REMOVE(ca, ca_list);
478 
479 	return 0;
480 }
481 
482 /*
483  * Look up a cfattach by name.
484  */
485 static struct cfattach *
486 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
487 {
488 	struct cfattach *ca;
489 
490 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
491 		if (STREQ(ca->ca_name, atname))
492 			return ca;
493 	}
494 
495 	return NULL;
496 }
497 
498 /*
499  * Look up a cfattach by driver/attachment name.
500  */
501 struct cfattach *
502 config_cfattach_lookup(const char *name, const char *atname)
503 {
504 	struct cfdriver *cd;
505 
506 	cd = config_cfdriver_lookup(name);
507 	if (cd == NULL)
508 		return NULL;
509 
510 	return config_cfattach_lookup_cd(cd, atname);
511 }
512 
513 /*
514  * Apply the matching function and choose the best.  This is used
515  * a few times and we want to keep the code small.
516  */
517 static void
518 mapply(struct matchinfo *m, cfdata_t cf)
519 {
520 	int pri;
521 
522 	if (m->fn != NULL) {
523 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
524 	} else {
525 		pri = config_match(m->parent, cf, m->aux);
526 	}
527 	if (pri > m->pri) {
528 		m->match = cf;
529 		m->pri = pri;
530 	}
531 }
532 
533 int
534 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
535 {
536 	const struct cfiattrdata *ci;
537 	const struct cflocdesc *cl;
538 	int nlocs, i;
539 
540 	ci = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
541 	KASSERT(ci);
542 	nlocs = ci->ci_loclen;
543 	KASSERT(!nlocs || locs);
544 	for (i = 0; i < nlocs; i++) {
545 		cl = &ci->ci_locdesc[i];
546 		/* !cld_defaultstr means no default value */
547 		if ((!(cl->cld_defaultstr)
548 		     || (cf->cf_loc[i] != cl->cld_default))
549 		    && cf->cf_loc[i] != locs[i])
550 			return 0;
551 	}
552 
553 	return config_match(parent, cf, aux);
554 }
555 
556 /*
557  * Helper function: check whether the driver supports the interface attribute
558  * and return its descriptor structure.
559  */
560 static const struct cfiattrdata *
561 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
562 {
563 	const struct cfiattrdata * const *cpp;
564 
565 	if (cd->cd_attrs == NULL)
566 		return 0;
567 
568 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
569 		if (STREQ((*cpp)->ci_name, ia)) {
570 			/* Match. */
571 			return *cpp;
572 		}
573 	}
574 	return 0;
575 }
576 
577 /*
578  * Lookup an interface attribute description by name.
579  * If the driver is given, consider only its supported attributes.
580  */
581 const struct cfiattrdata *
582 cfiattr_lookup(const char *name, const struct cfdriver *cd)
583 {
584 	const struct cfdriver *d;
585 	const struct cfiattrdata *ia;
586 
587 	if (cd)
588 		return cfdriver_get_iattr(cd, name);
589 
590 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
591 		ia = cfdriver_get_iattr(d, name);
592 		if (ia)
593 			return ia;
594 	}
595 	return 0;
596 }
597 
598 /*
599  * Determine if `parent' is a potential parent for a device spec based
600  * on `cfp'.
601  */
602 static int
603 cfparent_match(const device_t parent, const struct cfparent *cfp)
604 {
605 	struct cfdriver *pcd;
606 
607 	/* We don't match root nodes here. */
608 	if (cfp == NULL)
609 		return 0;
610 
611 	pcd = parent->dv_cfdriver;
612 	KASSERT(pcd != NULL);
613 
614 	/*
615 	 * First, ensure this parent has the correct interface
616 	 * attribute.
617 	 */
618 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
619 		return 0;
620 
621 	/*
622 	 * If no specific parent device instance was specified (i.e.
623 	 * we're attaching to the attribute only), we're done!
624 	 */
625 	if (cfp->cfp_parent == NULL)
626 		return 1;
627 
628 	/*
629 	 * Check the parent device's name.
630 	 */
631 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
632 		return 0;	/* not the same parent */
633 
634 	/*
635 	 * Make sure the unit number matches.
636 	 */
637 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
638 	    cfp->cfp_unit == parent->dv_unit)
639 		return 1;
640 
641 	/* Unit numbers don't match. */
642 	return 0;
643 }
644 
645 /*
646  * Helper for config_cfdata_attach(): check all devices whether it could be
647  * parent any attachment in the config data table passed, and rescan.
648  */
649 static void
650 rescan_with_cfdata(const struct cfdata *cf)
651 {
652 	device_t d;
653 	const struct cfdata *cf1;
654 	deviter_t di;
655 
656 
657 	/*
658 	 * "alldevs" is likely longer than a modules's cfdata, so make it
659 	 * the outer loop.
660 	 */
661 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
662 
663 		if (!(d->dv_cfattach->ca_rescan))
664 			continue;
665 
666 		for (cf1 = cf; cf1->cf_name; cf1++) {
667 
668 			if (!cfparent_match(d, cf1->cf_pspec))
669 				continue;
670 
671 			(*d->dv_cfattach->ca_rescan)(d,
672 				cfdata_ifattr(cf1), cf1->cf_loc);
673 		}
674 	}
675 	deviter_release(&di);
676 }
677 
678 /*
679  * Attach a supplemental config data table and rescan potential
680  * parent devices if required.
681  */
682 int
683 config_cfdata_attach(cfdata_t cf, int scannow)
684 {
685 	struct cftable *ct;
686 
687 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
688 	ct->ct_cfdata = cf;
689 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
690 
691 	if (scannow)
692 		rescan_with_cfdata(cf);
693 
694 	return 0;
695 }
696 
697 /*
698  * Helper for config_cfdata_detach: check whether a device is
699  * found through any attachment in the config data table.
700  */
701 static int
702 dev_in_cfdata(const struct device *d, const struct cfdata *cf)
703 {
704 	const struct cfdata *cf1;
705 
706 	for (cf1 = cf; cf1->cf_name; cf1++)
707 		if (d->dv_cfdata == cf1)
708 			return 1;
709 
710 	return 0;
711 }
712 
713 /*
714  * Detach a supplemental config data table. Detach all devices found
715  * through that table (and thus keeping references to it) before.
716  */
717 int
718 config_cfdata_detach(cfdata_t cf)
719 {
720 	device_t d;
721 	int error = 0;
722 	struct cftable *ct;
723 	deviter_t di;
724 
725 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
726 	     d = deviter_next(&di)) {
727 		if (!dev_in_cfdata(d, cf))
728 			continue;
729 		if ((error = config_detach(d, 0)) != 0)
730 			break;
731 	}
732 	deviter_release(&di);
733 	if (error) {
734 		aprint_error_dev(d, "unable to detach instance\n");
735 		return error;
736 	}
737 
738 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
739 		if (ct->ct_cfdata == cf) {
740 			TAILQ_REMOVE(&allcftables, ct, ct_list);
741 			kmem_free(ct, sizeof(*ct));
742 			return 0;
743 		}
744 	}
745 
746 	/* not found -- shouldn't happen */
747 	return EINVAL;
748 }
749 
750 /*
751  * Invoke the "match" routine for a cfdata entry on behalf of
752  * an external caller, usually a "submatch" routine.
753  */
754 int
755 config_match(device_t parent, cfdata_t cf, void *aux)
756 {
757 	struct cfattach *ca;
758 
759 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
760 	if (ca == NULL) {
761 		/* No attachment for this entry, oh well. */
762 		return 0;
763 	}
764 
765 	return (*ca->ca_match)(parent, cf, aux);
766 }
767 
768 /*
769  * Iterate over all potential children of some device, calling the given
770  * function (default being the child's match function) for each one.
771  * Nonzero returns are matches; the highest value returned is considered
772  * the best match.  Return the `found child' if we got a match, or NULL
773  * otherwise.  The `aux' pointer is simply passed on through.
774  *
775  * Note that this function is designed so that it can be used to apply
776  * an arbitrary function to all potential children (its return value
777  * can be ignored).
778  */
779 cfdata_t
780 config_search_loc(cfsubmatch_t fn, device_t parent,
781 		  const char *ifattr, const int *locs, void *aux)
782 {
783 	struct cftable *ct;
784 	cfdata_t cf;
785 	struct matchinfo m;
786 
787 	KASSERT(config_initialized);
788 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
789 
790 	m.fn = fn;
791 	m.parent = parent;
792 	m.locs = locs;
793 	m.aux = aux;
794 	m.match = NULL;
795 	m.pri = 0;
796 
797 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
798 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
799 
800 			/* We don't match root nodes here. */
801 			if (!cf->cf_pspec)
802 				continue;
803 
804 			/*
805 			 * Skip cf if no longer eligible, otherwise scan
806 			 * through parents for one matching `parent', and
807 			 * try match function.
808 			 */
809 			if (cf->cf_fstate == FSTATE_FOUND)
810 				continue;
811 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
812 			    cf->cf_fstate == FSTATE_DSTAR)
813 				continue;
814 
815 			/*
816 			 * If an interface attribute was specified,
817 			 * consider only children which attach to
818 			 * that attribute.
819 			 */
820 			if (ifattr && !STREQ(ifattr, cfdata_ifattr(cf)))
821 				continue;
822 
823 			if (cfparent_match(parent, cf->cf_pspec))
824 				mapply(&m, cf);
825 		}
826 	}
827 	return m.match;
828 }
829 
830 cfdata_t
831 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
832     void *aux)
833 {
834 
835 	return config_search_loc(fn, parent, ifattr, NULL, aux);
836 }
837 
838 /*
839  * Find the given root device.
840  * This is much like config_search, but there is no parent.
841  * Don't bother with multiple cfdata tables; the root node
842  * must always be in the initial table.
843  */
844 cfdata_t
845 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
846 {
847 	cfdata_t cf;
848 	const short *p;
849 	struct matchinfo m;
850 
851 	m.fn = fn;
852 	m.parent = ROOT;
853 	m.aux = aux;
854 	m.match = NULL;
855 	m.pri = 0;
856 	m.locs = 0;
857 	/*
858 	 * Look at root entries for matching name.  We do not bother
859 	 * with found-state here since only one root should ever be
860 	 * searched (and it must be done first).
861 	 */
862 	for (p = cfroots; *p >= 0; p++) {
863 		cf = &cfdata[*p];
864 		if (strcmp(cf->cf_name, rootname) == 0)
865 			mapply(&m, cf);
866 	}
867 	return m.match;
868 }
869 
870 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
871 
872 /*
873  * The given `aux' argument describes a device that has been found
874  * on the given parent, but not necessarily configured.  Locate the
875  * configuration data for that device (using the submatch function
876  * provided, or using candidates' cd_match configuration driver
877  * functions) and attach it, and return true.  If the device was
878  * not configured, call the given `print' function and return 0.
879  */
880 device_t
881 config_found_sm_loc(device_t parent,
882 		const char *ifattr, const int *locs, void *aux,
883 		cfprint_t print, cfsubmatch_t submatch)
884 {
885 	cfdata_t cf;
886 
887 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
888 	if (splash_progress_state)
889 		splash_progress_update(splash_progress_state);
890 #endif
891 
892 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
893 		return(config_attach_loc(parent, cf, locs, aux, print));
894 	if (print) {
895 		if (config_do_twiddle && cold)
896 			twiddle();
897 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
898 	}
899 
900 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
901 	if (splash_progress_state)
902 		splash_progress_update(splash_progress_state);
903 #endif
904 
905 	return NULL;
906 }
907 
908 device_t
909 config_found_ia(device_t parent, const char *ifattr, void *aux,
910     cfprint_t print)
911 {
912 
913 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
914 }
915 
916 device_t
917 config_found(device_t parent, void *aux, cfprint_t print)
918 {
919 
920 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
921 }
922 
923 /*
924  * As above, but for root devices.
925  */
926 device_t
927 config_rootfound(const char *rootname, void *aux)
928 {
929 	cfdata_t cf;
930 
931 	if ((cf = config_rootsearch((cfsubmatch_t)NULL, rootname, aux)) != NULL)
932 		return config_attach(ROOT, cf, aux, (cfprint_t)NULL);
933 	aprint_error("root device %s not configured\n", rootname);
934 	return NULL;
935 }
936 
937 /* just like sprintf(buf, "%d") except that it works from the end */
938 static char *
939 number(char *ep, int n)
940 {
941 
942 	*--ep = 0;
943 	while (n >= 10) {
944 		*--ep = (n % 10) + '0';
945 		n /= 10;
946 	}
947 	*--ep = n + '0';
948 	return ep;
949 }
950 
951 /*
952  * Expand the size of the cd_devs array if necessary.
953  *
954  * The caller must hold alldevs_mtx. config_makeroom() may release and
955  * re-acquire alldevs_mtx, so callers should re-check conditions such
956  * as alldevs_nwrite == 0 and alldevs_nread == 0 when config_makeroom()
957  * returns.
958  */
959 static void
960 config_makeroom(int n, struct cfdriver *cd)
961 {
962 	int old, new;
963 	device_t *osp, *nsp;
964 
965 	alldevs_nwrite++;
966 
967 	for (new = MAX(4, cd->cd_ndevs); new <= n; new += new)
968 		;
969 
970 	while (n >= cd->cd_ndevs) {
971 		/*
972 		 * Need to expand the array.
973 		 */
974 		old = cd->cd_ndevs;
975 		osp = cd->cd_devs;
976 
977 		/* Release alldevs_mtx around allocation, which may
978 		 * sleep.
979 		 */
980 		mutex_exit(&alldevs_mtx);
981 		nsp = kmem_alloc(sizeof(device_t[new]), KM_SLEEP);
982 		if (nsp == NULL)
983 			panic("%s: could not expand cd_devs", __func__);
984 		mutex_enter(&alldevs_mtx);
985 
986 		/* If another thread moved the array while we did
987 		 * not hold alldevs_mtx, try again.
988 		 */
989 		if (cd->cd_devs != osp) {
990 			kmem_free(nsp, sizeof(device_t[new]));
991 			continue;
992 		}
993 
994 		memset(nsp + old, 0, sizeof(device_t[new - old]));
995 		if (old != 0)
996 			memcpy(nsp, cd->cd_devs, sizeof(device_t[old]));
997 
998 		cd->cd_ndevs = new;
999 		cd->cd_devs = nsp;
1000 		if (old != 0)
1001 			kmem_free(osp, sizeof(device_t[old]));
1002 	}
1003 	alldevs_nwrite--;
1004 }
1005 
1006 /*
1007  * Put dev into the devices list.
1008  */
1009 static void
1010 config_devlink(device_t dev)
1011 {
1012 	int s;
1013 
1014 	s = config_alldevs_lock();
1015 
1016 	KASSERT(device_cfdriver(dev)->cd_devs[dev->dv_unit] == dev);
1017 
1018 	dev->dv_add_gen = alldevs_gen;
1019 	/* It is safe to add a device to the tail of the list while
1020 	 * readers and writers are in the list.
1021 	 */
1022 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);
1023 	config_alldevs_unlock(s);
1024 }
1025 
1026 static void
1027 config_devfree(device_t dev)
1028 {
1029 	int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
1030 
1031 	if (dev->dv_cfattach->ca_devsize > 0)
1032 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
1033 	if (priv)
1034 		kmem_free(dev, sizeof(*dev));
1035 }
1036 
1037 /*
1038  * Caller must hold alldevs_mtx.
1039  */
1040 static void
1041 config_devunlink(device_t dev, struct devicelist *garbage)
1042 {
1043 	struct device_garbage *dg = &dev->dv_garbage;
1044 	cfdriver_t cd = device_cfdriver(dev);
1045 	int i;
1046 
1047 	KASSERT(mutex_owned(&alldevs_mtx));
1048 
1049  	/* Unlink from device list.  Link to garbage list. */
1050 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1051 	TAILQ_INSERT_TAIL(garbage, dev, dv_list);
1052 
1053 	/* Remove from cfdriver's array. */
1054 	cd->cd_devs[dev->dv_unit] = NULL;
1055 
1056 	/*
1057 	 * If the device now has no units in use, unlink its softc array.
1058 	 */
1059 	for (i = 0; i < cd->cd_ndevs; i++) {
1060 		if (cd->cd_devs[i] != NULL)
1061 			break;
1062 	}
1063 	/* Nothing found.  Unlink, now.  Deallocate, later. */
1064 	if (i == cd->cd_ndevs) {
1065 		dg->dg_ndevs = cd->cd_ndevs;
1066 		dg->dg_devs = cd->cd_devs;
1067 		cd->cd_devs = NULL;
1068 		cd->cd_ndevs = 0;
1069 	}
1070 }
1071 
1072 static void
1073 config_devdelete(device_t dev)
1074 {
1075 	struct device_garbage *dg = &dev->dv_garbage;
1076 	device_lock_t dvl = device_getlock(dev);
1077 
1078 	if (dg->dg_devs != NULL)
1079 		kmem_free(dg->dg_devs, sizeof(device_t[dg->dg_ndevs]));
1080 
1081 	cv_destroy(&dvl->dvl_cv);
1082 	mutex_destroy(&dvl->dvl_mtx);
1083 
1084 	KASSERT(dev->dv_properties != NULL);
1085 	prop_object_release(dev->dv_properties);
1086 
1087 	if (dev->dv_activity_handlers)
1088 		panic("%s with registered handlers", __func__);
1089 
1090 	if (dev->dv_locators) {
1091 		size_t amount = *--dev->dv_locators;
1092 		kmem_free(dev->dv_locators, amount);
1093 	}
1094 
1095 	config_devfree(dev);
1096 }
1097 
1098 static int
1099 config_unit_nextfree(cfdriver_t cd, cfdata_t cf)
1100 {
1101 	int unit;
1102 
1103 	if (cf->cf_fstate == FSTATE_STAR) {
1104 		for (unit = cf->cf_unit; unit < cd->cd_ndevs; unit++)
1105 			if (cd->cd_devs[unit] == NULL)
1106 				break;
1107 		/*
1108 		 * unit is now the unit of the first NULL device pointer,
1109 		 * or max(cd->cd_ndevs,cf->cf_unit).
1110 		 */
1111 	} else {
1112 		unit = cf->cf_unit;
1113 		if (unit < cd->cd_ndevs && cd->cd_devs[unit] != NULL)
1114 			unit = -1;
1115 	}
1116 	return unit;
1117 }
1118 
1119 static int
1120 config_unit_alloc(device_t dev, cfdriver_t cd, cfdata_t cf)
1121 {
1122 	struct alldevs_foray af;
1123 	int unit;
1124 
1125 	config_alldevs_enter(&af);
1126 	for (;;) {
1127 		unit = config_unit_nextfree(cd, cf);
1128 		if (unit == -1)
1129 			break;
1130 		if (unit < cd->cd_ndevs) {
1131 			cd->cd_devs[unit] = dev;
1132 			dev->dv_unit = unit;
1133 			break;
1134 		}
1135 		config_makeroom(unit, cd);
1136 	}
1137 	config_alldevs_exit(&af);
1138 
1139 	return unit;
1140 }
1141 
1142 static device_t
1143 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1144 {
1145 	cfdriver_t cd;
1146 	cfattach_t ca;
1147 	size_t lname, lunit;
1148 	const char *xunit;
1149 	int myunit;
1150 	char num[10];
1151 	device_t dev;
1152 	void *dev_private;
1153 	const struct cfiattrdata *ia;
1154 	device_lock_t dvl;
1155 
1156 	cd = config_cfdriver_lookup(cf->cf_name);
1157 	if (cd == NULL)
1158 		return NULL;
1159 
1160 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1161 	if (ca == NULL)
1162 		return NULL;
1163 
1164 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
1165 	    ca->ca_devsize < sizeof(struct device))
1166 		panic("config_devalloc: %s", cf->cf_atname);
1167 
1168 	/* get memory for all device vars */
1169 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
1170 	if (ca->ca_devsize > 0) {
1171 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
1172 		if (dev_private == NULL)
1173 			panic("config_devalloc: memory allocation for device softc failed");
1174 	} else {
1175 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1176 		dev_private = NULL;
1177 	}
1178 
1179 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
1180 		dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
1181 	} else {
1182 		dev = dev_private;
1183 	}
1184 	if (dev == NULL)
1185 		panic("config_devalloc: memory allocation for device_t failed");
1186 
1187 	dev->dv_class = cd->cd_class;
1188 	dev->dv_cfdata = cf;
1189 	dev->dv_cfdriver = cd;
1190 	dev->dv_cfattach = ca;
1191 	dev->dv_activity_count = 0;
1192 	dev->dv_activity_handlers = NULL;
1193 	dev->dv_private = dev_private;
1194 	dev->dv_flags = ca->ca_flags;	/* inherit flags from class */
1195 
1196 	myunit = config_unit_alloc(dev, cd, cf);
1197 	if (myunit == -1) {
1198 		config_devfree(dev);
1199 		return NULL;
1200 	}
1201 
1202 	/* compute length of name and decimal expansion of unit number */
1203 	lname = strlen(cd->cd_name);
1204 	xunit = number(&num[sizeof(num)], myunit);
1205 	lunit = &num[sizeof(num)] - xunit;
1206 	if (lname + lunit > sizeof(dev->dv_xname))
1207 		panic("config_devalloc: device name too long");
1208 
1209 	dvl = device_getlock(dev);
1210 
1211 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
1212 	cv_init(&dvl->dvl_cv, "pmfsusp");
1213 
1214 	memcpy(dev->dv_xname, cd->cd_name, lname);
1215 	memcpy(dev->dv_xname + lname, xunit, lunit);
1216 	dev->dv_parent = parent;
1217 	if (parent != NULL)
1218 		dev->dv_depth = parent->dv_depth + 1;
1219 	else
1220 		dev->dv_depth = 0;
1221 	dev->dv_flags |= DVF_ACTIVE;	/* always initially active */
1222 	if (locs) {
1223 		KASSERT(parent); /* no locators at root */
1224 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
1225 		dev->dv_locators =
1226 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
1227 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
1228 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
1229 	}
1230 	dev->dv_properties = prop_dictionary_create();
1231 	KASSERT(dev->dv_properties != NULL);
1232 
1233 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
1234 	    "device-driver", dev->dv_cfdriver->cd_name);
1235 	prop_dictionary_set_uint16(dev->dv_properties,
1236 	    "device-unit", dev->dv_unit);
1237 
1238 	return dev;
1239 }
1240 
1241 /*
1242  * Attach a found device.
1243  */
1244 device_t
1245 config_attach_loc(device_t parent, cfdata_t cf,
1246 	const int *locs, void *aux, cfprint_t print)
1247 {
1248 	device_t dev;
1249 	struct cftable *ct;
1250 	const char *drvname;
1251 
1252 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1253 	if (splash_progress_state)
1254 		splash_progress_update(splash_progress_state);
1255 #endif
1256 
1257 	dev = config_devalloc(parent, cf, locs);
1258 	if (!dev)
1259 		panic("config_attach: allocation of device softc failed");
1260 
1261 	/* XXX redundant - see below? */
1262 	if (cf->cf_fstate != FSTATE_STAR) {
1263 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1264 		cf->cf_fstate = FSTATE_FOUND;
1265 	}
1266 
1267 	config_devlink(dev);
1268 
1269 	if (config_do_twiddle && cold)
1270 		twiddle();
1271 	else
1272 		aprint_naive("Found ");
1273 	/*
1274 	 * We want the next two printfs for normal, verbose, and quiet,
1275 	 * but not silent (in which case, we're twiddling, instead).
1276 	 */
1277 	if (parent == ROOT) {
1278 		aprint_naive("%s (root)", device_xname(dev));
1279 		aprint_normal("%s (root)", device_xname(dev));
1280 	} else {
1281 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
1282 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
1283 		if (print)
1284 			(void) (*print)(aux, NULL);
1285 	}
1286 
1287 	/*
1288 	 * Before attaching, clobber any unfound devices that are
1289 	 * otherwise identical.
1290 	 * XXX code above is redundant?
1291 	 */
1292 	drvname = dev->dv_cfdriver->cd_name;
1293 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1294 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1295 			if (STREQ(cf->cf_name, drvname) &&
1296 			    cf->cf_unit == dev->dv_unit) {
1297 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1298 					cf->cf_fstate = FSTATE_FOUND;
1299 			}
1300 		}
1301 	}
1302 #ifdef __HAVE_DEVICE_REGISTER
1303 	device_register(dev, aux);
1304 #endif
1305 
1306 	/* Let userland know */
1307 	devmon_report_device(dev, true);
1308 
1309 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1310 	if (splash_progress_state)
1311 		splash_progress_update(splash_progress_state);
1312 #endif
1313 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1314 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1315 	if (splash_progress_state)
1316 		splash_progress_update(splash_progress_state);
1317 #endif
1318 
1319 	if (!device_pmf_is_registered(dev))
1320 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1321 
1322 	config_process_deferred(&deferred_config_queue, dev);
1323 
1324 #ifdef __HAVE_DEVICE_REGISTER_POSTCONFIG
1325 	device_register_post_config(dev, aux);
1326 #endif
1327 	return dev;
1328 }
1329 
1330 device_t
1331 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1332 {
1333 
1334 	return config_attach_loc(parent, cf, NULL, aux, print);
1335 }
1336 
1337 /*
1338  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1339  * way are silently inserted into the device tree, and their children
1340  * attached.
1341  *
1342  * Note that because pseudo-devices are attached silently, any information
1343  * the attach routine wishes to print should be prefixed with the device
1344  * name by the attach routine.
1345  */
1346 device_t
1347 config_attach_pseudo(cfdata_t cf)
1348 {
1349 	device_t dev;
1350 
1351 	dev = config_devalloc(ROOT, cf, NULL);
1352 	if (!dev)
1353 		return NULL;
1354 
1355 	/* XXX mark busy in cfdata */
1356 
1357 	if (cf->cf_fstate != FSTATE_STAR) {
1358 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1359 		cf->cf_fstate = FSTATE_FOUND;
1360 	}
1361 
1362 	config_devlink(dev);
1363 
1364 #if 0	/* XXXJRT not yet */
1365 #ifdef __HAVE_DEVICE_REGISTER
1366 	device_register(dev, NULL);	/* like a root node */
1367 #endif
1368 #endif
1369 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1370 	config_process_deferred(&deferred_config_queue, dev);
1371 	return dev;
1372 }
1373 
1374 /*
1375  * Caller must hold alldevs_mtx.
1376  */
1377 static void
1378 config_collect_garbage(struct devicelist *garbage)
1379 {
1380 	device_t dv;
1381 
1382 	KASSERT(!cpu_intr_p());
1383 	KASSERT(!cpu_softintr_p());
1384 	KASSERT(mutex_owned(&alldevs_mtx));
1385 
1386 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
1387 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
1388 			if (dv->dv_del_gen != 0)
1389 				break;
1390 		}
1391 		if (dv == NULL) {
1392 			alldevs_garbage = false;
1393 			break;
1394 		}
1395 		config_devunlink(dv, garbage);
1396 	}
1397 	KASSERT(mutex_owned(&alldevs_mtx));
1398 }
1399 
1400 static void
1401 config_dump_garbage(struct devicelist *garbage)
1402 {
1403 	device_t dv;
1404 
1405 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
1406 		TAILQ_REMOVE(garbage, dv, dv_list);
1407 		config_devdelete(dv);
1408 	}
1409 }
1410 
1411 /*
1412  * Detach a device.  Optionally forced (e.g. because of hardware
1413  * removal) and quiet.  Returns zero if successful, non-zero
1414  * (an error code) otherwise.
1415  *
1416  * Note that this code wants to be run from a process context, so
1417  * that the detach can sleep to allow processes which have a device
1418  * open to run and unwind their stacks.
1419  */
1420 int
1421 config_detach(device_t dev, int flags)
1422 {
1423 	struct alldevs_foray af;
1424 	struct cftable *ct;
1425 	cfdata_t cf;
1426 	const struct cfattach *ca;
1427 	struct cfdriver *cd;
1428 #ifdef DIAGNOSTIC
1429 	device_t d;
1430 #endif
1431 	int rv = 0, s;
1432 
1433 #ifdef DIAGNOSTIC
1434 	cf = dev->dv_cfdata;
1435 	if (cf != NULL && cf->cf_fstate != FSTATE_FOUND &&
1436 	    cf->cf_fstate != FSTATE_STAR)
1437 		panic("config_detach: %s: bad device fstate %d",
1438 		    device_xname(dev), cf ? cf->cf_fstate : -1);
1439 #endif
1440 	cd = dev->dv_cfdriver;
1441 	KASSERT(cd != NULL);
1442 
1443 	ca = dev->dv_cfattach;
1444 	KASSERT(ca != NULL);
1445 
1446 	s = config_alldevs_lock();
1447 	if (dev->dv_del_gen != 0) {
1448 		config_alldevs_unlock(s);
1449 #ifdef DIAGNOSTIC
1450 		printf("%s: %s is already detached\n", __func__,
1451 		    device_xname(dev));
1452 #endif /* DIAGNOSTIC */
1453 		return ENOENT;
1454 	}
1455 	alldevs_nwrite++;
1456 	config_alldevs_unlock(s);
1457 
1458 	if (!detachall &&
1459 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
1460 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
1461 		rv = EOPNOTSUPP;
1462 	} else if (ca->ca_detach != NULL) {
1463 		rv = (*ca->ca_detach)(dev, flags);
1464 	} else
1465 		rv = EOPNOTSUPP;
1466 
1467 	/*
1468 	 * If it was not possible to detach the device, then we either
1469 	 * panic() (for the forced but failed case), or return an error.
1470 	 *
1471 	 * If it was possible to detach the device, ensure that the
1472 	 * device is deactivated.
1473 	 */
1474 	if (rv == 0)
1475 		dev->dv_flags &= ~DVF_ACTIVE;
1476 	else if ((flags & DETACH_FORCE) == 0)
1477 		goto out;
1478 	else {
1479 		panic("config_detach: forced detach of %s failed (%d)",
1480 		    device_xname(dev), rv);
1481 	}
1482 
1483 	/*
1484 	 * The device has now been successfully detached.
1485 	 */
1486 
1487 	/* Let userland know */
1488 	devmon_report_device(dev, false);
1489 
1490 #ifdef DIAGNOSTIC
1491 	/*
1492 	 * Sanity: If you're successfully detached, you should have no
1493 	 * children.  (Note that because children must be attached
1494 	 * after parents, we only need to search the latter part of
1495 	 * the list.)
1496 	 */
1497 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1498 	    d = TAILQ_NEXT(d, dv_list)) {
1499 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
1500 			printf("config_detach: detached device %s"
1501 			    " has children %s\n", device_xname(dev), device_xname(d));
1502 			panic("config_detach");
1503 		}
1504 	}
1505 #endif
1506 
1507 	/* notify the parent that the child is gone */
1508 	if (dev->dv_parent) {
1509 		device_t p = dev->dv_parent;
1510 		if (p->dv_cfattach->ca_childdetached)
1511 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1512 	}
1513 
1514 	/*
1515 	 * Mark cfdata to show that the unit can be reused, if possible.
1516 	 */
1517 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1518 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1519 			if (STREQ(cf->cf_name, cd->cd_name)) {
1520 				if (cf->cf_fstate == FSTATE_FOUND &&
1521 				    cf->cf_unit == dev->dv_unit)
1522 					cf->cf_fstate = FSTATE_NOTFOUND;
1523 			}
1524 		}
1525 	}
1526 
1527 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1528 		aprint_normal_dev(dev, "detached\n");
1529 
1530 out:
1531 	config_alldevs_enter(&af);
1532 	KASSERT(alldevs_nwrite != 0);
1533 	--alldevs_nwrite;
1534 	if (rv == 0 && dev->dv_del_gen == 0)
1535 		config_devunlink(dev, &af.af_garbage);
1536 	config_alldevs_exit(&af);
1537 
1538 	return rv;
1539 }
1540 
1541 int
1542 config_detach_children(device_t parent, int flags)
1543 {
1544 	device_t dv;
1545 	deviter_t di;
1546 	int error = 0;
1547 
1548 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1549 	     dv = deviter_next(&di)) {
1550 		if (device_parent(dv) != parent)
1551 			continue;
1552 		if ((error = config_detach(dv, flags)) != 0)
1553 			break;
1554 	}
1555 	deviter_release(&di);
1556 	return error;
1557 }
1558 
1559 device_t
1560 shutdown_first(struct shutdown_state *s)
1561 {
1562 	if (!s->initialized) {
1563 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
1564 		s->initialized = true;
1565 	}
1566 	return shutdown_next(s);
1567 }
1568 
1569 device_t
1570 shutdown_next(struct shutdown_state *s)
1571 {
1572 	device_t dv;
1573 
1574 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
1575 		;
1576 
1577 	if (dv == NULL)
1578 		s->initialized = false;
1579 
1580 	return dv;
1581 }
1582 
1583 bool
1584 config_detach_all(int how)
1585 {
1586 	static struct shutdown_state s;
1587 	device_t curdev;
1588 	bool progress = false;
1589 
1590 	if ((how & RB_NOSYNC) != 0)
1591 		return false;
1592 
1593 	for (curdev = shutdown_first(&s); curdev != NULL;
1594 	     curdev = shutdown_next(&s)) {
1595 		aprint_debug(" detaching %s, ", device_xname(curdev));
1596 		if (config_detach(curdev, DETACH_SHUTDOWN) == 0) {
1597 			progress = true;
1598 			aprint_debug("success.");
1599 		} else
1600 			aprint_debug("failed.");
1601 	}
1602 	return progress;
1603 }
1604 
1605 static bool
1606 device_is_ancestor_of(device_t ancestor, device_t descendant)
1607 {
1608 	device_t dv;
1609 
1610 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
1611 		if (device_parent(dv) == ancestor)
1612 			return true;
1613 	}
1614 	return false;
1615 }
1616 
1617 int
1618 config_deactivate(device_t dev)
1619 {
1620 	deviter_t di;
1621 	const struct cfattach *ca;
1622 	device_t descendant;
1623 	int s, rv = 0, oflags;
1624 
1625 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
1626 	     descendant != NULL;
1627 	     descendant = deviter_next(&di)) {
1628 		if (dev != descendant &&
1629 		    !device_is_ancestor_of(dev, descendant))
1630 			continue;
1631 
1632 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
1633 			continue;
1634 
1635 		ca = descendant->dv_cfattach;
1636 		oflags = descendant->dv_flags;
1637 
1638 		descendant->dv_flags &= ~DVF_ACTIVE;
1639 		if (ca->ca_activate == NULL)
1640 			continue;
1641 		s = splhigh();
1642 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
1643 		splx(s);
1644 		if (rv != 0)
1645 			descendant->dv_flags = oflags;
1646 	}
1647 	deviter_release(&di);
1648 	return rv;
1649 }
1650 
1651 /*
1652  * Defer the configuration of the specified device until all
1653  * of its parent's devices have been attached.
1654  */
1655 void
1656 config_defer(device_t dev, void (*func)(device_t))
1657 {
1658 	struct deferred_config *dc;
1659 
1660 	if (dev->dv_parent == NULL)
1661 		panic("config_defer: can't defer config of a root device");
1662 
1663 #ifdef DIAGNOSTIC
1664 	TAILQ_FOREACH(dc, &deferred_config_queue, dc_queue) {
1665 		if (dc->dc_dev == dev)
1666 			panic("config_defer: deferred twice");
1667 	}
1668 #endif
1669 
1670 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1671 	if (dc == NULL)
1672 		panic("config_defer: unable to allocate callback");
1673 
1674 	dc->dc_dev = dev;
1675 	dc->dc_func = func;
1676 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1677 	config_pending_incr();
1678 }
1679 
1680 /*
1681  * Defer some autoconfiguration for a device until after interrupts
1682  * are enabled.
1683  */
1684 void
1685 config_interrupts(device_t dev, void (*func)(device_t))
1686 {
1687 	struct deferred_config *dc;
1688 
1689 	/*
1690 	 * If interrupts are enabled, callback now.
1691 	 */
1692 	if (cold == 0) {
1693 		(*func)(dev);
1694 		return;
1695 	}
1696 
1697 #ifdef DIAGNOSTIC
1698 	TAILQ_FOREACH(dc, &interrupt_config_queue, dc_queue) {
1699 		if (dc->dc_dev == dev)
1700 			panic("config_interrupts: deferred twice");
1701 	}
1702 #endif
1703 
1704 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1705 	if (dc == NULL)
1706 		panic("config_interrupts: unable to allocate callback");
1707 
1708 	dc->dc_dev = dev;
1709 	dc->dc_func = func;
1710 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1711 	config_pending_incr();
1712 }
1713 
1714 /*
1715  * Process a deferred configuration queue.
1716  */
1717 static void
1718 config_process_deferred(struct deferred_config_head *queue,
1719     device_t parent)
1720 {
1721 	struct deferred_config *dc, *ndc;
1722 
1723 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1724 		ndc = TAILQ_NEXT(dc, dc_queue);
1725 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1726 			TAILQ_REMOVE(queue, dc, dc_queue);
1727 			(*dc->dc_func)(dc->dc_dev);
1728 			kmem_free(dc, sizeof(*dc));
1729 			config_pending_decr();
1730 		}
1731 	}
1732 }
1733 
1734 /*
1735  * Manipulate the config_pending semaphore.
1736  */
1737 void
1738 config_pending_incr(void)
1739 {
1740 
1741 	mutex_enter(&config_misc_lock);
1742 	config_pending++;
1743 	mutex_exit(&config_misc_lock);
1744 }
1745 
1746 void
1747 config_pending_decr(void)
1748 {
1749 
1750 #ifdef DIAGNOSTIC
1751 	if (config_pending == 0)
1752 		panic("config_pending_decr: config_pending == 0");
1753 #endif
1754 	mutex_enter(&config_misc_lock);
1755 	config_pending--;
1756 	if (config_pending == 0)
1757 		cv_broadcast(&config_misc_cv);
1758 	mutex_exit(&config_misc_lock);
1759 }
1760 
1761 /*
1762  * Register a "finalization" routine.  Finalization routines are
1763  * called iteratively once all real devices have been found during
1764  * autoconfiguration, for as long as any one finalizer has done
1765  * any work.
1766  */
1767 int
1768 config_finalize_register(device_t dev, int (*fn)(device_t))
1769 {
1770 	struct finalize_hook *f;
1771 
1772 	/*
1773 	 * If finalization has already been done, invoke the
1774 	 * callback function now.
1775 	 */
1776 	if (config_finalize_done) {
1777 		while ((*fn)(dev) != 0)
1778 			/* loop */ ;
1779 	}
1780 
1781 	/* Ensure this isn't already on the list. */
1782 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1783 		if (f->f_func == fn && f->f_dev == dev)
1784 			return EEXIST;
1785 	}
1786 
1787 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
1788 	f->f_func = fn;
1789 	f->f_dev = dev;
1790 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1791 
1792 	return 0;
1793 }
1794 
1795 void
1796 config_finalize(void)
1797 {
1798 	struct finalize_hook *f;
1799 	struct pdevinit *pdev;
1800 	extern struct pdevinit pdevinit[];
1801 	int errcnt, rv;
1802 
1803 	/*
1804 	 * Now that device driver threads have been created, wait for
1805 	 * them to finish any deferred autoconfiguration.
1806 	 */
1807 	mutex_enter(&config_misc_lock);
1808 	while (config_pending != 0)
1809 		cv_wait(&config_misc_cv, &config_misc_lock);
1810 	mutex_exit(&config_misc_lock);
1811 
1812 	KERNEL_LOCK(1, NULL);
1813 
1814 	/* Attach pseudo-devices. */
1815 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
1816 		(*pdev->pdev_attach)(pdev->pdev_count);
1817 
1818 	/* Run the hooks until none of them does any work. */
1819 	do {
1820 		rv = 0;
1821 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1822 			rv |= (*f->f_func)(f->f_dev);
1823 	} while (rv != 0);
1824 
1825 	config_finalize_done = 1;
1826 
1827 	/* Now free all the hooks. */
1828 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1829 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1830 		kmem_free(f, sizeof(*f));
1831 	}
1832 
1833 	KERNEL_UNLOCK_ONE(NULL);
1834 
1835 	errcnt = aprint_get_error_count();
1836 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
1837 	    (boothowto & AB_VERBOSE) == 0) {
1838 		mutex_enter(&config_misc_lock);
1839 		if (config_do_twiddle) {
1840 			config_do_twiddle = 0;
1841 			printf_nolog(" done.\n");
1842 		}
1843 		mutex_exit(&config_misc_lock);
1844 		if (errcnt != 0) {
1845 			printf("WARNING: %d error%s while detecting hardware; "
1846 			    "check system log.\n", errcnt,
1847 			    errcnt == 1 ? "" : "s");
1848 		}
1849 	}
1850 }
1851 
1852 void
1853 config_twiddle_init()
1854 {
1855 
1856 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
1857 		config_do_twiddle = 1;
1858 	}
1859 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
1860 }
1861 
1862 void
1863 config_twiddle_fn(void *cookie)
1864 {
1865 
1866 	mutex_enter(&config_misc_lock);
1867 	if (config_do_twiddle) {
1868 		twiddle();
1869 		callout_schedule(&config_twiddle_ch, mstohz(100));
1870 	}
1871 	mutex_exit(&config_misc_lock);
1872 }
1873 
1874 static int
1875 config_alldevs_lock(void)
1876 {
1877 	int s;
1878 
1879 	s = splhigh();
1880 	mutex_enter(&alldevs_mtx);
1881 	return s;
1882 }
1883 
1884 static void
1885 config_alldevs_enter(struct alldevs_foray *af)
1886 {
1887 	TAILQ_INIT(&af->af_garbage);
1888 	af->af_s = config_alldevs_lock();
1889 	config_collect_garbage(&af->af_garbage);
1890 }
1891 
1892 static void
1893 config_alldevs_exit(struct alldevs_foray *af)
1894 {
1895 	config_alldevs_unlock(af->af_s);
1896 	config_dump_garbage(&af->af_garbage);
1897 }
1898 
1899 static void
1900 config_alldevs_unlock(int s)
1901 {
1902 	mutex_exit(&alldevs_mtx);
1903 	splx(s);
1904 }
1905 
1906 /*
1907  * device_lookup:
1908  *
1909  *	Look up a device instance for a given driver.
1910  */
1911 device_t
1912 device_lookup(cfdriver_t cd, int unit)
1913 {
1914 	device_t dv;
1915 	int s;
1916 
1917 	s = config_alldevs_lock();
1918 	KASSERT(mutex_owned(&alldevs_mtx));
1919 	if (unit < 0 || unit >= cd->cd_ndevs)
1920 		dv = NULL;
1921 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
1922 		dv = NULL;
1923 	config_alldevs_unlock(s);
1924 
1925 	return dv;
1926 }
1927 
1928 /*
1929  * device_lookup_private:
1930  *
1931  *	Look up a softc instance for a given driver.
1932  */
1933 void *
1934 device_lookup_private(cfdriver_t cd, int unit)
1935 {
1936 
1937 	return device_private(device_lookup(cd, unit));
1938 }
1939 
1940 /*
1941  * device_find_by_xname:
1942  *
1943  *	Returns the device of the given name or NULL if it doesn't exist.
1944  */
1945 device_t
1946 device_find_by_xname(const char *name)
1947 {
1948 	device_t dv;
1949 	deviter_t di;
1950 
1951 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
1952 		if (strcmp(device_xname(dv), name) == 0)
1953 			break;
1954 	}
1955 	deviter_release(&di);
1956 
1957 	return dv;
1958 }
1959 
1960 /*
1961  * device_find_by_driver_unit:
1962  *
1963  *	Returns the device of the given driver name and unit or
1964  *	NULL if it doesn't exist.
1965  */
1966 device_t
1967 device_find_by_driver_unit(const char *name, int unit)
1968 {
1969 	struct cfdriver *cd;
1970 
1971 	if ((cd = config_cfdriver_lookup(name)) == NULL)
1972 		return NULL;
1973 	return device_lookup(cd, unit);
1974 }
1975 
1976 /*
1977  * Power management related functions.
1978  */
1979 
1980 bool
1981 device_pmf_is_registered(device_t dev)
1982 {
1983 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
1984 }
1985 
1986 bool
1987 device_pmf_driver_suspend(device_t dev, const pmf_qual_t *qual)
1988 {
1989 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
1990 		return true;
1991 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
1992 		return false;
1993 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
1994 	    dev->dv_driver_suspend != NULL &&
1995 	    !(*dev->dv_driver_suspend)(dev, qual))
1996 		return false;
1997 
1998 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
1999 	return true;
2000 }
2001 
2002 bool
2003 device_pmf_driver_resume(device_t dev, const pmf_qual_t *qual)
2004 {
2005 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2006 		return true;
2007 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2008 		return false;
2009 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2010 	    dev->dv_driver_resume != NULL &&
2011 	    !(*dev->dv_driver_resume)(dev, qual))
2012 		return false;
2013 
2014 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2015 	return true;
2016 }
2017 
2018 bool
2019 device_pmf_driver_shutdown(device_t dev, int how)
2020 {
2021 
2022 	if (*dev->dv_driver_shutdown != NULL &&
2023 	    !(*dev->dv_driver_shutdown)(dev, how))
2024 		return false;
2025 	return true;
2026 }
2027 
2028 bool
2029 device_pmf_driver_register(device_t dev,
2030     bool (*suspend)(device_t, const pmf_qual_t *),
2031     bool (*resume)(device_t, const pmf_qual_t *),
2032     bool (*shutdown)(device_t, int))
2033 {
2034 	dev->dv_driver_suspend = suspend;
2035 	dev->dv_driver_resume = resume;
2036 	dev->dv_driver_shutdown = shutdown;
2037 	dev->dv_flags |= DVF_POWER_HANDLERS;
2038 	return true;
2039 }
2040 
2041 static const char *
2042 curlwp_name(void)
2043 {
2044 	if (curlwp->l_name != NULL)
2045 		return curlwp->l_name;
2046 	else
2047 		return curlwp->l_proc->p_comm;
2048 }
2049 
2050 void
2051 device_pmf_driver_deregister(device_t dev)
2052 {
2053 	device_lock_t dvl = device_getlock(dev);
2054 
2055 	dev->dv_driver_suspend = NULL;
2056 	dev->dv_driver_resume = NULL;
2057 
2058 	mutex_enter(&dvl->dvl_mtx);
2059 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2060 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
2061 		/* Wake a thread that waits for the lock.  That
2062 		 * thread will fail to acquire the lock, and then
2063 		 * it will wake the next thread that waits for the
2064 		 * lock, or else it will wake us.
2065 		 */
2066 		cv_signal(&dvl->dvl_cv);
2067 		pmflock_debug(dev, __func__, __LINE__);
2068 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2069 		pmflock_debug(dev, __func__, __LINE__);
2070 	}
2071 	mutex_exit(&dvl->dvl_mtx);
2072 }
2073 
2074 bool
2075 device_pmf_driver_child_register(device_t dev)
2076 {
2077 	device_t parent = device_parent(dev);
2078 
2079 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2080 		return true;
2081 	return (*parent->dv_driver_child_register)(dev);
2082 }
2083 
2084 void
2085 device_pmf_driver_set_child_register(device_t dev,
2086     bool (*child_register)(device_t))
2087 {
2088 	dev->dv_driver_child_register = child_register;
2089 }
2090 
2091 static void
2092 pmflock_debug(device_t dev, const char *func, int line)
2093 {
2094 	device_lock_t dvl = device_getlock(dev);
2095 
2096 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n",
2097 	    func, line, curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait,
2098 	    dev->dv_flags);
2099 }
2100 
2101 static bool
2102 device_pmf_lock1(device_t dev)
2103 {
2104 	device_lock_t dvl = device_getlock(dev);
2105 
2106 	while (device_pmf_is_registered(dev) &&
2107 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
2108 		dvl->dvl_nwait++;
2109 		pmflock_debug(dev, __func__, __LINE__);
2110 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2111 		pmflock_debug(dev, __func__, __LINE__);
2112 		dvl->dvl_nwait--;
2113 	}
2114 	if (!device_pmf_is_registered(dev)) {
2115 		pmflock_debug(dev, __func__, __LINE__);
2116 		/* We could not acquire the lock, but some other thread may
2117 		 * wait for it, also.  Wake that thread.
2118 		 */
2119 		cv_signal(&dvl->dvl_cv);
2120 		return false;
2121 	}
2122 	dvl->dvl_nlock++;
2123 	dvl->dvl_holder = curlwp;
2124 	pmflock_debug(dev, __func__, __LINE__);
2125 	return true;
2126 }
2127 
2128 bool
2129 device_pmf_lock(device_t dev)
2130 {
2131 	bool rc;
2132 	device_lock_t dvl = device_getlock(dev);
2133 
2134 	mutex_enter(&dvl->dvl_mtx);
2135 	rc = device_pmf_lock1(dev);
2136 	mutex_exit(&dvl->dvl_mtx);
2137 
2138 	return rc;
2139 }
2140 
2141 void
2142 device_pmf_unlock(device_t dev)
2143 {
2144 	device_lock_t dvl = device_getlock(dev);
2145 
2146 	KASSERT(dvl->dvl_nlock > 0);
2147 	mutex_enter(&dvl->dvl_mtx);
2148 	if (--dvl->dvl_nlock == 0)
2149 		dvl->dvl_holder = NULL;
2150 	cv_signal(&dvl->dvl_cv);
2151 	pmflock_debug(dev, __func__, __LINE__);
2152 	mutex_exit(&dvl->dvl_mtx);
2153 }
2154 
2155 device_lock_t
2156 device_getlock(device_t dev)
2157 {
2158 	return &dev->dv_lock;
2159 }
2160 
2161 void *
2162 device_pmf_bus_private(device_t dev)
2163 {
2164 	return dev->dv_bus_private;
2165 }
2166 
2167 bool
2168 device_pmf_bus_suspend(device_t dev, const pmf_qual_t *qual)
2169 {
2170 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2171 		return true;
2172 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2173 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2174 		return false;
2175 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2176 	    dev->dv_bus_suspend != NULL &&
2177 	    !(*dev->dv_bus_suspend)(dev, qual))
2178 		return false;
2179 
2180 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2181 	return true;
2182 }
2183 
2184 bool
2185 device_pmf_bus_resume(device_t dev, const pmf_qual_t *qual)
2186 {
2187 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2188 		return true;
2189 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2190 	    dev->dv_bus_resume != NULL &&
2191 	    !(*dev->dv_bus_resume)(dev, qual))
2192 		return false;
2193 
2194 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2195 	return true;
2196 }
2197 
2198 bool
2199 device_pmf_bus_shutdown(device_t dev, int how)
2200 {
2201 
2202 	if (*dev->dv_bus_shutdown != NULL &&
2203 	    !(*dev->dv_bus_shutdown)(dev, how))
2204 		return false;
2205 	return true;
2206 }
2207 
2208 void
2209 device_pmf_bus_register(device_t dev, void *priv,
2210     bool (*suspend)(device_t, const pmf_qual_t *),
2211     bool (*resume)(device_t, const pmf_qual_t *),
2212     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2213 {
2214 	dev->dv_bus_private = priv;
2215 	dev->dv_bus_resume = resume;
2216 	dev->dv_bus_suspend = suspend;
2217 	dev->dv_bus_shutdown = shutdown;
2218 	dev->dv_bus_deregister = deregister;
2219 }
2220 
2221 void
2222 device_pmf_bus_deregister(device_t dev)
2223 {
2224 	if (dev->dv_bus_deregister == NULL)
2225 		return;
2226 	(*dev->dv_bus_deregister)(dev);
2227 	dev->dv_bus_private = NULL;
2228 	dev->dv_bus_suspend = NULL;
2229 	dev->dv_bus_resume = NULL;
2230 	dev->dv_bus_deregister = NULL;
2231 }
2232 
2233 void *
2234 device_pmf_class_private(device_t dev)
2235 {
2236 	return dev->dv_class_private;
2237 }
2238 
2239 bool
2240 device_pmf_class_suspend(device_t dev, const pmf_qual_t *qual)
2241 {
2242 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2243 		return true;
2244 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2245 	    dev->dv_class_suspend != NULL &&
2246 	    !(*dev->dv_class_suspend)(dev, qual))
2247 		return false;
2248 
2249 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2250 	return true;
2251 }
2252 
2253 bool
2254 device_pmf_class_resume(device_t dev, const pmf_qual_t *qual)
2255 {
2256 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2257 		return true;
2258 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2259 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2260 		return false;
2261 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2262 	    dev->dv_class_resume != NULL &&
2263 	    !(*dev->dv_class_resume)(dev, qual))
2264 		return false;
2265 
2266 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2267 	return true;
2268 }
2269 
2270 void
2271 device_pmf_class_register(device_t dev, void *priv,
2272     bool (*suspend)(device_t, const pmf_qual_t *),
2273     bool (*resume)(device_t, const pmf_qual_t *),
2274     void (*deregister)(device_t))
2275 {
2276 	dev->dv_class_private = priv;
2277 	dev->dv_class_suspend = suspend;
2278 	dev->dv_class_resume = resume;
2279 	dev->dv_class_deregister = deregister;
2280 }
2281 
2282 void
2283 device_pmf_class_deregister(device_t dev)
2284 {
2285 	if (dev->dv_class_deregister == NULL)
2286 		return;
2287 	(*dev->dv_class_deregister)(dev);
2288 	dev->dv_class_private = NULL;
2289 	dev->dv_class_suspend = NULL;
2290 	dev->dv_class_resume = NULL;
2291 	dev->dv_class_deregister = NULL;
2292 }
2293 
2294 bool
2295 device_active(device_t dev, devactive_t type)
2296 {
2297 	size_t i;
2298 
2299 	if (dev->dv_activity_count == 0)
2300 		return false;
2301 
2302 	for (i = 0; i < dev->dv_activity_count; ++i) {
2303 		if (dev->dv_activity_handlers[i] == NULL)
2304 			break;
2305 		(*dev->dv_activity_handlers[i])(dev, type);
2306 	}
2307 
2308 	return true;
2309 }
2310 
2311 bool
2312 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2313 {
2314 	void (**new_handlers)(device_t, devactive_t);
2315 	void (**old_handlers)(device_t, devactive_t);
2316 	size_t i, old_size, new_size;
2317 	int s;
2318 
2319 	old_handlers = dev->dv_activity_handlers;
2320 	old_size = dev->dv_activity_count;
2321 
2322 	for (i = 0; i < old_size; ++i) {
2323 		KASSERT(old_handlers[i] != handler);
2324 		if (old_handlers[i] == NULL) {
2325 			old_handlers[i] = handler;
2326 			return true;
2327 		}
2328 	}
2329 
2330 	new_size = old_size + 4;
2331 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
2332 
2333 	memcpy(new_handlers, old_handlers, sizeof(void *[old_size]));
2334 	new_handlers[old_size] = handler;
2335 	memset(new_handlers + old_size + 1, 0,
2336 	    sizeof(int [new_size - (old_size+1)]));
2337 
2338 	s = splhigh();
2339 	dev->dv_activity_count = new_size;
2340 	dev->dv_activity_handlers = new_handlers;
2341 	splx(s);
2342 
2343 	if (old_handlers != NULL)
2344 		kmem_free(old_handlers, sizeof(void * [old_size]));
2345 
2346 	return true;
2347 }
2348 
2349 void
2350 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2351 {
2352 	void (**old_handlers)(device_t, devactive_t);
2353 	size_t i, old_size;
2354 	int s;
2355 
2356 	old_handlers = dev->dv_activity_handlers;
2357 	old_size = dev->dv_activity_count;
2358 
2359 	for (i = 0; i < old_size; ++i) {
2360 		if (old_handlers[i] == handler)
2361 			break;
2362 		if (old_handlers[i] == NULL)
2363 			return; /* XXX panic? */
2364 	}
2365 
2366 	if (i == old_size)
2367 		return; /* XXX panic? */
2368 
2369 	for (; i < old_size - 1; ++i) {
2370 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
2371 			continue;
2372 
2373 		if (i == 0) {
2374 			s = splhigh();
2375 			dev->dv_activity_count = 0;
2376 			dev->dv_activity_handlers = NULL;
2377 			splx(s);
2378 			kmem_free(old_handlers, sizeof(void *[old_size]));
2379 		}
2380 		return;
2381 	}
2382 	old_handlers[i] = NULL;
2383 }
2384 
2385 /* Return true iff the device_t `dev' exists at generation `gen'. */
2386 static bool
2387 device_exists_at(device_t dv, devgen_t gen)
2388 {
2389 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
2390 	    dv->dv_add_gen <= gen;
2391 }
2392 
2393 static bool
2394 deviter_visits(const deviter_t *di, device_t dv)
2395 {
2396 	return device_exists_at(dv, di->di_gen);
2397 }
2398 
2399 /*
2400  * Device Iteration
2401  *
2402  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2403  *     each device_t's in the device tree.
2404  *
2405  * deviter_init(di, flags): initialize the device iterator `di'
2406  *     to "walk" the device tree.  deviter_next(di) will return
2407  *     the first device_t in the device tree, or NULL if there are
2408  *     no devices.
2409  *
2410  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2411  *     caller intends to modify the device tree by calling
2412  *     config_detach(9) on devices in the order that the iterator
2413  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2414  *     nearest the "root" of the device tree to be returned, first;
2415  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2416  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2417  *     indicating both that deviter_init() should not respect any
2418  *     locks on the device tree, and that deviter_next(di) may run
2419  *     in more than one LWP before the walk has finished.
2420  *
2421  *     Only one DEVITER_F_RW iterator may be in the device tree at
2422  *     once.
2423  *
2424  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2425  *
2426  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2427  *     DEVITER_F_LEAVES_FIRST are used in combination.
2428  *
2429  * deviter_first(di, flags): initialize the device iterator `di'
2430  *     and return the first device_t in the device tree, or NULL
2431  *     if there are no devices.  The statement
2432  *
2433  *         dv = deviter_first(di);
2434  *
2435  *     is shorthand for
2436  *
2437  *         deviter_init(di);
2438  *         dv = deviter_next(di);
2439  *
2440  * deviter_next(di): return the next device_t in the device tree,
2441  *     or NULL if there are no more devices.  deviter_next(di)
2442  *     is undefined if `di' was not initialized with deviter_init() or
2443  *     deviter_first().
2444  *
2445  * deviter_release(di): stops iteration (subsequent calls to
2446  *     deviter_next() will return NULL), releases any locks and
2447  *     resources held by the device iterator.
2448  *
2449  * Device iteration does not return device_t's in any particular
2450  * order.  An iterator will never return the same device_t twice.
2451  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2452  * is called repeatedly on the same `di', it will eventually return
2453  * NULL.  It is ok to attach/detach devices during device iteration.
2454  */
2455 void
2456 deviter_init(deviter_t *di, deviter_flags_t flags)
2457 {
2458 	device_t dv;
2459 	int s;
2460 
2461 	memset(di, 0, sizeof(*di));
2462 
2463 	s = config_alldevs_lock();
2464 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
2465 		flags |= DEVITER_F_RW;
2466 
2467 	if ((flags & DEVITER_F_RW) != 0)
2468 		alldevs_nwrite++;
2469 	else
2470 		alldevs_nread++;
2471 	di->di_gen = alldevs_gen++;
2472 	config_alldevs_unlock(s);
2473 
2474 	di->di_flags = flags;
2475 
2476 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2477 	case DEVITER_F_LEAVES_FIRST:
2478 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2479 			if (!deviter_visits(di, dv))
2480 				continue;
2481 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2482 		}
2483 		break;
2484 	case DEVITER_F_ROOT_FIRST:
2485 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2486 			if (!deviter_visits(di, dv))
2487 				continue;
2488 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2489 		}
2490 		break;
2491 	default:
2492 		break;
2493 	}
2494 
2495 	deviter_reinit(di);
2496 }
2497 
2498 static void
2499 deviter_reinit(deviter_t *di)
2500 {
2501 	if ((di->di_flags & DEVITER_F_RW) != 0)
2502 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2503 	else
2504 		di->di_prev = TAILQ_FIRST(&alldevs);
2505 }
2506 
2507 device_t
2508 deviter_first(deviter_t *di, deviter_flags_t flags)
2509 {
2510 	deviter_init(di, flags);
2511 	return deviter_next(di);
2512 }
2513 
2514 static device_t
2515 deviter_next2(deviter_t *di)
2516 {
2517 	device_t dv;
2518 
2519 	dv = di->di_prev;
2520 
2521 	if (dv == NULL)
2522 		return NULL;
2523 
2524 	if ((di->di_flags & DEVITER_F_RW) != 0)
2525 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2526 	else
2527 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2528 
2529 	return dv;
2530 }
2531 
2532 static device_t
2533 deviter_next1(deviter_t *di)
2534 {
2535 	device_t dv;
2536 
2537 	do {
2538 		dv = deviter_next2(di);
2539 	} while (dv != NULL && !deviter_visits(di, dv));
2540 
2541 	return dv;
2542 }
2543 
2544 device_t
2545 deviter_next(deviter_t *di)
2546 {
2547 	device_t dv = NULL;
2548 
2549 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2550 	case 0:
2551 		return deviter_next1(di);
2552 	case DEVITER_F_LEAVES_FIRST:
2553 		while (di->di_curdepth >= 0) {
2554 			if ((dv = deviter_next1(di)) == NULL) {
2555 				di->di_curdepth--;
2556 				deviter_reinit(di);
2557 			} else if (dv->dv_depth == di->di_curdepth)
2558 				break;
2559 		}
2560 		return dv;
2561 	case DEVITER_F_ROOT_FIRST:
2562 		while (di->di_curdepth <= di->di_maxdepth) {
2563 			if ((dv = deviter_next1(di)) == NULL) {
2564 				di->di_curdepth++;
2565 				deviter_reinit(di);
2566 			} else if (dv->dv_depth == di->di_curdepth)
2567 				break;
2568 		}
2569 		return dv;
2570 	default:
2571 		return NULL;
2572 	}
2573 }
2574 
2575 void
2576 deviter_release(deviter_t *di)
2577 {
2578 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2579 	int s;
2580 
2581 	s = config_alldevs_lock();
2582 	if (rw)
2583 		--alldevs_nwrite;
2584 	else
2585 		--alldevs_nread;
2586 	/* XXX wake a garbage-collection thread */
2587 	config_alldevs_unlock(s);
2588 }
2589 
2590 const char *
2591 cfdata_ifattr(const struct cfdata *cf)
2592 {
2593 	return cf->cf_pspec->cfp_iattr;
2594 }
2595 
2596 bool
2597 ifattr_match(const char *snull, const char *t)
2598 {
2599 	return (snull == NULL) || strcmp(snull, t) == 0;
2600 }
2601 
2602 void
2603 null_childdetached(device_t self, device_t child)
2604 {
2605 	/* do nothing */
2606 }
2607 
2608 static void
2609 sysctl_detach_setup(struct sysctllog **clog)
2610 {
2611 	const struct sysctlnode *node = NULL;
2612 
2613 	sysctl_createv(clog, 0, NULL, &node,
2614 		CTLFLAG_PERMANENT,
2615 		CTLTYPE_NODE, "kern", NULL,
2616 		NULL, 0, NULL, 0,
2617 		CTL_KERN, CTL_EOL);
2618 
2619 	if (node == NULL)
2620 		return;
2621 
2622 	sysctl_createv(clog, 0, &node, NULL,
2623 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
2624 		CTLTYPE_INT, "detachall",
2625 		SYSCTL_DESCR("Detach all devices at shutdown"),
2626 		NULL, 0, &detachall, 0,
2627 		CTL_CREATE, CTL_EOL);
2628 }
2629