xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 01ce72cef8d1825e9af5cd97c3bfc82185fd5e1f)
1 /* $NetBSD: subr_autoconf.c,v 1.201 2010/02/15 20:20:34 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 1.201 2010/02/15 20:20:34 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 	myunit = config_unit_alloc(dev, cd, cf);
1188 	if (myunit == -1) {
1189 		config_devfree(dev);
1190 		return NULL;
1191 	}
1192 
1193 	/* compute length of name and decimal expansion of unit number */
1194 	lname = strlen(cd->cd_name);
1195 	xunit = number(&num[sizeof(num)], myunit);
1196 	lunit = &num[sizeof(num)] - xunit;
1197 	if (lname + lunit > sizeof(dev->dv_xname))
1198 		panic("config_devalloc: device name too long");
1199 
1200 	dvl = device_getlock(dev);
1201 
1202 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
1203 	cv_init(&dvl->dvl_cv, "pmfsusp");
1204 
1205 	dev->dv_class = cd->cd_class;
1206 	dev->dv_cfdata = cf;
1207 	dev->dv_cfdriver = cd;
1208 	dev->dv_cfattach = ca;
1209 	dev->dv_activity_count = 0;
1210 	dev->dv_activity_handlers = NULL;
1211 	dev->dv_private = dev_private;
1212 	memcpy(dev->dv_xname, cd->cd_name, lname);
1213 	memcpy(dev->dv_xname + lname, xunit, lunit);
1214 	dev->dv_parent = parent;
1215 	if (parent != NULL)
1216 		dev->dv_depth = parent->dv_depth + 1;
1217 	else
1218 		dev->dv_depth = 0;
1219 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
1220 	dev->dv_flags |= ca->ca_flags;	/* inherit flags from class */
1221 	if (locs) {
1222 		KASSERT(parent); /* no locators at root */
1223 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
1224 		dev->dv_locators =
1225 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
1226 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
1227 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
1228 	}
1229 	dev->dv_properties = prop_dictionary_create();
1230 	KASSERT(dev->dv_properties != NULL);
1231 
1232 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
1233 	    "device-driver", dev->dv_cfdriver->cd_name);
1234 	prop_dictionary_set_uint16(dev->dv_properties,
1235 	    "device-unit", dev->dv_unit);
1236 
1237 	return dev;
1238 }
1239 
1240 /*
1241  * Attach a found device.
1242  */
1243 device_t
1244 config_attach_loc(device_t parent, cfdata_t cf,
1245 	const int *locs, void *aux, cfprint_t print)
1246 {
1247 	device_t dev;
1248 	struct cftable *ct;
1249 	const char *drvname;
1250 
1251 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1252 	if (splash_progress_state)
1253 		splash_progress_update(splash_progress_state);
1254 #endif
1255 
1256 	dev = config_devalloc(parent, cf, locs);
1257 	if (!dev)
1258 		panic("config_attach: allocation of device softc failed");
1259 
1260 	/* XXX redundant - see below? */
1261 	if (cf->cf_fstate != FSTATE_STAR) {
1262 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1263 		cf->cf_fstate = FSTATE_FOUND;
1264 	}
1265 
1266 	config_devlink(dev);
1267 
1268 	if (config_do_twiddle && cold)
1269 		twiddle();
1270 	else
1271 		aprint_naive("Found ");
1272 	/*
1273 	 * We want the next two printfs for normal, verbose, and quiet,
1274 	 * but not silent (in which case, we're twiddling, instead).
1275 	 */
1276 	if (parent == ROOT) {
1277 		aprint_naive("%s (root)", device_xname(dev));
1278 		aprint_normal("%s (root)", device_xname(dev));
1279 	} else {
1280 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
1281 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
1282 		if (print)
1283 			(void) (*print)(aux, NULL);
1284 	}
1285 
1286 	/*
1287 	 * Before attaching, clobber any unfound devices that are
1288 	 * otherwise identical.
1289 	 * XXX code above is redundant?
1290 	 */
1291 	drvname = dev->dv_cfdriver->cd_name;
1292 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1293 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1294 			if (STREQ(cf->cf_name, drvname) &&
1295 			    cf->cf_unit == dev->dv_unit) {
1296 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1297 					cf->cf_fstate = FSTATE_FOUND;
1298 			}
1299 		}
1300 	}
1301 #ifdef __HAVE_DEVICE_REGISTER
1302 	device_register(dev, aux);
1303 #endif
1304 
1305 	/* Let userland know */
1306 	devmon_report_device(dev, true);
1307 
1308 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1309 	if (splash_progress_state)
1310 		splash_progress_update(splash_progress_state);
1311 #endif
1312 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1313 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1314 	if (splash_progress_state)
1315 		splash_progress_update(splash_progress_state);
1316 #endif
1317 
1318 	if (!device_pmf_is_registered(dev))
1319 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1320 
1321 	config_process_deferred(&deferred_config_queue, dev);
1322 
1323 #ifdef __HAVE_DEVICE_REGISTER_POSTCONFIG
1324 	device_register_post_config(dev, aux);
1325 #endif
1326 	return dev;
1327 }
1328 
1329 device_t
1330 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1331 {
1332 
1333 	return config_attach_loc(parent, cf, NULL, aux, print);
1334 }
1335 
1336 /*
1337  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1338  * way are silently inserted into the device tree, and their children
1339  * attached.
1340  *
1341  * Note that because pseudo-devices are attached silently, any information
1342  * the attach routine wishes to print should be prefixed with the device
1343  * name by the attach routine.
1344  */
1345 device_t
1346 config_attach_pseudo(cfdata_t cf)
1347 {
1348 	device_t dev;
1349 
1350 	dev = config_devalloc(ROOT, cf, NULL);
1351 	if (!dev)
1352 		return NULL;
1353 
1354 	/* XXX mark busy in cfdata */
1355 
1356 	if (cf->cf_fstate != FSTATE_STAR) {
1357 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1358 		cf->cf_fstate = FSTATE_FOUND;
1359 	}
1360 
1361 	config_devlink(dev);
1362 
1363 #if 0	/* XXXJRT not yet */
1364 #ifdef __HAVE_DEVICE_REGISTER
1365 	device_register(dev, NULL);	/* like a root node */
1366 #endif
1367 #endif
1368 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1369 	config_process_deferred(&deferred_config_queue, dev);
1370 	return dev;
1371 }
1372 
1373 /*
1374  * Caller must hold alldevs_mtx.
1375  */
1376 static void
1377 config_collect_garbage(struct devicelist *garbage)
1378 {
1379 	device_t dv;
1380 
1381 	KASSERT(!cpu_intr_p());
1382 	KASSERT(!cpu_softintr_p());
1383 	KASSERT(mutex_owned(&alldevs_mtx));
1384 
1385 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
1386 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
1387 			if (dv->dv_del_gen != 0)
1388 				break;
1389 		}
1390 		if (dv == NULL) {
1391 			alldevs_garbage = false;
1392 			break;
1393 		}
1394 		config_devunlink(dv, garbage);
1395 	}
1396 	KASSERT(mutex_owned(&alldevs_mtx));
1397 }
1398 
1399 static void
1400 config_dump_garbage(struct devicelist *garbage)
1401 {
1402 	device_t dv;
1403 
1404 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
1405 		TAILQ_REMOVE(garbage, dv, dv_list);
1406 		config_devdelete(dv);
1407 	}
1408 }
1409 
1410 /*
1411  * Detach a device.  Optionally forced (e.g. because of hardware
1412  * removal) and quiet.  Returns zero if successful, non-zero
1413  * (an error code) otherwise.
1414  *
1415  * Note that this code wants to be run from a process context, so
1416  * that the detach can sleep to allow processes which have a device
1417  * open to run and unwind their stacks.
1418  */
1419 int
1420 config_detach(device_t dev, int flags)
1421 {
1422 	struct alldevs_foray af;
1423 	struct cftable *ct;
1424 	cfdata_t cf;
1425 	const struct cfattach *ca;
1426 	struct cfdriver *cd;
1427 #ifdef DIAGNOSTIC
1428 	device_t d;
1429 #endif
1430 	int rv = 0, s;
1431 
1432 #ifdef DIAGNOSTIC
1433 	cf = dev->dv_cfdata;
1434 	if (cf != NULL && cf->cf_fstate != FSTATE_FOUND &&
1435 	    cf->cf_fstate != FSTATE_STAR)
1436 		panic("config_detach: %s: bad device fstate %d",
1437 		    device_xname(dev), cf ? cf->cf_fstate : -1);
1438 #endif
1439 	cd = dev->dv_cfdriver;
1440 	KASSERT(cd != NULL);
1441 
1442 	ca = dev->dv_cfattach;
1443 	KASSERT(ca != NULL);
1444 
1445 	s = config_alldevs_lock();
1446 	if (dev->dv_del_gen != 0) {
1447 		config_alldevs_unlock(s);
1448 #ifdef DIAGNOSTIC
1449 		printf("%s: %s is already detached\n", __func__,
1450 		    device_xname(dev));
1451 #endif /* DIAGNOSTIC */
1452 		return ENOENT;
1453 	}
1454 	alldevs_nwrite++;
1455 	config_alldevs_unlock(s);
1456 
1457 	if (!detachall &&
1458 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
1459 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
1460 		rv = EOPNOTSUPP;
1461 	} else if (ca->ca_detach != NULL) {
1462 		rv = (*ca->ca_detach)(dev, flags);
1463 	} else
1464 		rv = EOPNOTSUPP;
1465 
1466 	/*
1467 	 * If it was not possible to detach the device, then we either
1468 	 * panic() (for the forced but failed case), or return an error.
1469 	 *
1470 	 * If it was possible to detach the device, ensure that the
1471 	 * device is deactivated.
1472 	 */
1473 	if (rv == 0)
1474 		dev->dv_flags &= ~DVF_ACTIVE;
1475 	else if ((flags & DETACH_FORCE) == 0)
1476 		goto out;
1477 	else {
1478 		panic("config_detach: forced detach of %s failed (%d)",
1479 		    device_xname(dev), rv);
1480 	}
1481 
1482 	/*
1483 	 * The device has now been successfully detached.
1484 	 */
1485 
1486 	/* Let userland know */
1487 	devmon_report_device(dev, false);
1488 
1489 #ifdef DIAGNOSTIC
1490 	/*
1491 	 * Sanity: If you're successfully detached, you should have no
1492 	 * children.  (Note that because children must be attached
1493 	 * after parents, we only need to search the latter part of
1494 	 * the list.)
1495 	 */
1496 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1497 	    d = TAILQ_NEXT(d, dv_list)) {
1498 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
1499 			printf("config_detach: detached device %s"
1500 			    " has children %s\n", device_xname(dev), device_xname(d));
1501 			panic("config_detach");
1502 		}
1503 	}
1504 #endif
1505 
1506 	/* notify the parent that the child is gone */
1507 	if (dev->dv_parent) {
1508 		device_t p = dev->dv_parent;
1509 		if (p->dv_cfattach->ca_childdetached)
1510 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1511 	}
1512 
1513 	/*
1514 	 * Mark cfdata to show that the unit can be reused, if possible.
1515 	 */
1516 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1517 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1518 			if (STREQ(cf->cf_name, cd->cd_name)) {
1519 				if (cf->cf_fstate == FSTATE_FOUND &&
1520 				    cf->cf_unit == dev->dv_unit)
1521 					cf->cf_fstate = FSTATE_NOTFOUND;
1522 			}
1523 		}
1524 	}
1525 
1526 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1527 		aprint_normal_dev(dev, "detached\n");
1528 
1529 out:
1530 	config_alldevs_enter(&af);
1531 	KASSERT(alldevs_nwrite != 0);
1532 	--alldevs_nwrite;
1533 	if (rv == 0 && dev->dv_del_gen == 0)
1534 		config_devunlink(dev, &af.af_garbage);
1535 	config_alldevs_exit(&af);
1536 
1537 	return rv;
1538 }
1539 
1540 int
1541 config_detach_children(device_t parent, int flags)
1542 {
1543 	device_t dv;
1544 	deviter_t di;
1545 	int error = 0;
1546 
1547 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1548 	     dv = deviter_next(&di)) {
1549 		if (device_parent(dv) != parent)
1550 			continue;
1551 		if ((error = config_detach(dv, flags)) != 0)
1552 			break;
1553 	}
1554 	deviter_release(&di);
1555 	return error;
1556 }
1557 
1558 device_t
1559 shutdown_first(struct shutdown_state *s)
1560 {
1561 	if (!s->initialized) {
1562 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
1563 		s->initialized = true;
1564 	}
1565 	return shutdown_next(s);
1566 }
1567 
1568 device_t
1569 shutdown_next(struct shutdown_state *s)
1570 {
1571 	device_t dv;
1572 
1573 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
1574 		;
1575 
1576 	if (dv == NULL)
1577 		s->initialized = false;
1578 
1579 	return dv;
1580 }
1581 
1582 bool
1583 config_detach_all(int how)
1584 {
1585 	static struct shutdown_state s;
1586 	device_t curdev;
1587 	bool progress = false;
1588 
1589 	if ((how & RB_NOSYNC) != 0)
1590 		return false;
1591 
1592 	for (curdev = shutdown_first(&s); curdev != NULL;
1593 	     curdev = shutdown_next(&s)) {
1594 		aprint_debug(" detaching %s, ", device_xname(curdev));
1595 		if (config_detach(curdev, DETACH_SHUTDOWN) == 0) {
1596 			progress = true;
1597 			aprint_debug("success.");
1598 		} else
1599 			aprint_debug("failed.");
1600 	}
1601 	return progress;
1602 }
1603 
1604 static bool
1605 device_is_ancestor_of(device_t ancestor, device_t descendant)
1606 {
1607 	device_t dv;
1608 
1609 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
1610 		if (device_parent(dv) == ancestor)
1611 			return true;
1612 	}
1613 	return false;
1614 }
1615 
1616 int
1617 config_deactivate(device_t dev)
1618 {
1619 	deviter_t di;
1620 	const struct cfattach *ca;
1621 	device_t descendant;
1622 	int s, rv = 0, oflags;
1623 
1624 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
1625 	     descendant != NULL;
1626 	     descendant = deviter_next(&di)) {
1627 		if (dev != descendant &&
1628 		    !device_is_ancestor_of(dev, descendant))
1629 			continue;
1630 
1631 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
1632 			continue;
1633 
1634 		ca = descendant->dv_cfattach;
1635 		oflags = descendant->dv_flags;
1636 
1637 		descendant->dv_flags &= ~DVF_ACTIVE;
1638 		if (ca->ca_activate == NULL)
1639 			continue;
1640 		s = splhigh();
1641 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
1642 		splx(s);
1643 		if (rv != 0)
1644 			descendant->dv_flags = oflags;
1645 	}
1646 	deviter_release(&di);
1647 	return rv;
1648 }
1649 
1650 /*
1651  * Defer the configuration of the specified device until all
1652  * of its parent's devices have been attached.
1653  */
1654 void
1655 config_defer(device_t dev, void (*func)(device_t))
1656 {
1657 	struct deferred_config *dc;
1658 
1659 	if (dev->dv_parent == NULL)
1660 		panic("config_defer: can't defer config of a root device");
1661 
1662 #ifdef DIAGNOSTIC
1663 	TAILQ_FOREACH(dc, &deferred_config_queue, dc_queue) {
1664 		if (dc->dc_dev == dev)
1665 			panic("config_defer: deferred twice");
1666 	}
1667 #endif
1668 
1669 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1670 	if (dc == NULL)
1671 		panic("config_defer: unable to allocate callback");
1672 
1673 	dc->dc_dev = dev;
1674 	dc->dc_func = func;
1675 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1676 	config_pending_incr();
1677 }
1678 
1679 /*
1680  * Defer some autoconfiguration for a device until after interrupts
1681  * are enabled.
1682  */
1683 void
1684 config_interrupts(device_t dev, void (*func)(device_t))
1685 {
1686 	struct deferred_config *dc;
1687 
1688 	/*
1689 	 * If interrupts are enabled, callback now.
1690 	 */
1691 	if (cold == 0) {
1692 		(*func)(dev);
1693 		return;
1694 	}
1695 
1696 #ifdef DIAGNOSTIC
1697 	TAILQ_FOREACH(dc, &interrupt_config_queue, dc_queue) {
1698 		if (dc->dc_dev == dev)
1699 			panic("config_interrupts: deferred twice");
1700 	}
1701 #endif
1702 
1703 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1704 	if (dc == NULL)
1705 		panic("config_interrupts: unable to allocate callback");
1706 
1707 	dc->dc_dev = dev;
1708 	dc->dc_func = func;
1709 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1710 	config_pending_incr();
1711 }
1712 
1713 /*
1714  * Process a deferred configuration queue.
1715  */
1716 static void
1717 config_process_deferred(struct deferred_config_head *queue,
1718     device_t parent)
1719 {
1720 	struct deferred_config *dc, *ndc;
1721 
1722 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1723 		ndc = TAILQ_NEXT(dc, dc_queue);
1724 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1725 			TAILQ_REMOVE(queue, dc, dc_queue);
1726 			(*dc->dc_func)(dc->dc_dev);
1727 			kmem_free(dc, sizeof(*dc));
1728 			config_pending_decr();
1729 		}
1730 	}
1731 }
1732 
1733 /*
1734  * Manipulate the config_pending semaphore.
1735  */
1736 void
1737 config_pending_incr(void)
1738 {
1739 
1740 	mutex_enter(&config_misc_lock);
1741 	config_pending++;
1742 	mutex_exit(&config_misc_lock);
1743 }
1744 
1745 void
1746 config_pending_decr(void)
1747 {
1748 
1749 #ifdef DIAGNOSTIC
1750 	if (config_pending == 0)
1751 		panic("config_pending_decr: config_pending == 0");
1752 #endif
1753 	mutex_enter(&config_misc_lock);
1754 	config_pending--;
1755 	if (config_pending == 0)
1756 		cv_broadcast(&config_misc_cv);
1757 	mutex_exit(&config_misc_lock);
1758 }
1759 
1760 /*
1761  * Register a "finalization" routine.  Finalization routines are
1762  * called iteratively once all real devices have been found during
1763  * autoconfiguration, for as long as any one finalizer has done
1764  * any work.
1765  */
1766 int
1767 config_finalize_register(device_t dev, int (*fn)(device_t))
1768 {
1769 	struct finalize_hook *f;
1770 
1771 	/*
1772 	 * If finalization has already been done, invoke the
1773 	 * callback function now.
1774 	 */
1775 	if (config_finalize_done) {
1776 		while ((*fn)(dev) != 0)
1777 			/* loop */ ;
1778 	}
1779 
1780 	/* Ensure this isn't already on the list. */
1781 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1782 		if (f->f_func == fn && f->f_dev == dev)
1783 			return EEXIST;
1784 	}
1785 
1786 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
1787 	f->f_func = fn;
1788 	f->f_dev = dev;
1789 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1790 
1791 	return 0;
1792 }
1793 
1794 void
1795 config_finalize(void)
1796 {
1797 	struct finalize_hook *f;
1798 	struct pdevinit *pdev;
1799 	extern struct pdevinit pdevinit[];
1800 	int errcnt, rv;
1801 
1802 	/*
1803 	 * Now that device driver threads have been created, wait for
1804 	 * them to finish any deferred autoconfiguration.
1805 	 */
1806 	mutex_enter(&config_misc_lock);
1807 	while (config_pending != 0)
1808 		cv_wait(&config_misc_cv, &config_misc_lock);
1809 	mutex_exit(&config_misc_lock);
1810 
1811 	KERNEL_LOCK(1, NULL);
1812 
1813 	/* Attach pseudo-devices. */
1814 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
1815 		(*pdev->pdev_attach)(pdev->pdev_count);
1816 
1817 	/* Run the hooks until none of them does any work. */
1818 	do {
1819 		rv = 0;
1820 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1821 			rv |= (*f->f_func)(f->f_dev);
1822 	} while (rv != 0);
1823 
1824 	config_finalize_done = 1;
1825 
1826 	/* Now free all the hooks. */
1827 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1828 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1829 		kmem_free(f, sizeof(*f));
1830 	}
1831 
1832 	KERNEL_UNLOCK_ONE(NULL);
1833 
1834 	errcnt = aprint_get_error_count();
1835 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
1836 	    (boothowto & AB_VERBOSE) == 0) {
1837 		mutex_enter(&config_misc_lock);
1838 		if (config_do_twiddle) {
1839 			config_do_twiddle = 0;
1840 			printf_nolog(" done.\n");
1841 		}
1842 		mutex_exit(&config_misc_lock);
1843 		if (errcnt != 0) {
1844 			printf("WARNING: %d error%s while detecting hardware; "
1845 			    "check system log.\n", errcnt,
1846 			    errcnt == 1 ? "" : "s");
1847 		}
1848 	}
1849 }
1850 
1851 void
1852 config_twiddle_init()
1853 {
1854 
1855 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
1856 		config_do_twiddle = 1;
1857 	}
1858 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
1859 }
1860 
1861 void
1862 config_twiddle_fn(void *cookie)
1863 {
1864 
1865 	mutex_enter(&config_misc_lock);
1866 	if (config_do_twiddle) {
1867 		twiddle();
1868 		callout_schedule(&config_twiddle_ch, mstohz(100));
1869 	}
1870 	mutex_exit(&config_misc_lock);
1871 }
1872 
1873 static int
1874 config_alldevs_lock(void)
1875 {
1876 	int s;
1877 
1878 	s = splhigh();
1879 	mutex_enter(&alldevs_mtx);
1880 	return s;
1881 }
1882 
1883 static void
1884 config_alldevs_enter(struct alldevs_foray *af)
1885 {
1886 	TAILQ_INIT(&af->af_garbage);
1887 	af->af_s = config_alldevs_lock();
1888 	config_collect_garbage(&af->af_garbage);
1889 }
1890 
1891 static void
1892 config_alldevs_exit(struct alldevs_foray *af)
1893 {
1894 	config_alldevs_unlock(af->af_s);
1895 	config_dump_garbage(&af->af_garbage);
1896 }
1897 
1898 static void
1899 config_alldevs_unlock(int s)
1900 {
1901 	mutex_exit(&alldevs_mtx);
1902 	splx(s);
1903 }
1904 
1905 /*
1906  * device_lookup:
1907  *
1908  *	Look up a device instance for a given driver.
1909  */
1910 device_t
1911 device_lookup(cfdriver_t cd, int unit)
1912 {
1913 	device_t dv;
1914 	int s;
1915 
1916 	s = config_alldevs_lock();
1917 	KASSERT(mutex_owned(&alldevs_mtx));
1918 	if (unit < 0 || unit >= cd->cd_ndevs)
1919 		dv = NULL;
1920 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
1921 		dv = NULL;
1922 	config_alldevs_unlock(s);
1923 
1924 	return dv;
1925 }
1926 
1927 /*
1928  * device_lookup_private:
1929  *
1930  *	Look up a softc instance for a given driver.
1931  */
1932 void *
1933 device_lookup_private(cfdriver_t cd, int unit)
1934 {
1935 
1936 	return device_private(device_lookup(cd, unit));
1937 }
1938 
1939 /*
1940  * device_find_by_xname:
1941  *
1942  *	Returns the device of the given name or NULL if it doesn't exist.
1943  */
1944 device_t
1945 device_find_by_xname(const char *name)
1946 {
1947 	device_t dv;
1948 	deviter_t di;
1949 
1950 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
1951 		if (strcmp(device_xname(dv), name) == 0)
1952 			break;
1953 	}
1954 	deviter_release(&di);
1955 
1956 	return dv;
1957 }
1958 
1959 /*
1960  * device_find_by_driver_unit:
1961  *
1962  *	Returns the device of the given driver name and unit or
1963  *	NULL if it doesn't exist.
1964  */
1965 device_t
1966 device_find_by_driver_unit(const char *name, int unit)
1967 {
1968 	struct cfdriver *cd;
1969 
1970 	if ((cd = config_cfdriver_lookup(name)) == NULL)
1971 		return NULL;
1972 	return device_lookup(cd, unit);
1973 }
1974 
1975 /*
1976  * Power management related functions.
1977  */
1978 
1979 bool
1980 device_pmf_is_registered(device_t dev)
1981 {
1982 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
1983 }
1984 
1985 bool
1986 device_pmf_driver_suspend(device_t dev, pmf_qual_t qual)
1987 {
1988 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
1989 		return true;
1990 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
1991 		return false;
1992 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
1993 	    dev->dv_driver_suspend != NULL &&
1994 	    !(*dev->dv_driver_suspend)(dev, qual))
1995 		return false;
1996 
1997 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
1998 	return true;
1999 }
2000 
2001 bool
2002 device_pmf_driver_resume(device_t dev, pmf_qual_t qual)
2003 {
2004 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2005 		return true;
2006 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2007 		return false;
2008 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2009 	    dev->dv_driver_resume != NULL &&
2010 	    !(*dev->dv_driver_resume)(dev, qual))
2011 		return false;
2012 
2013 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2014 	return true;
2015 }
2016 
2017 bool
2018 device_pmf_driver_shutdown(device_t dev, int how)
2019 {
2020 
2021 	if (*dev->dv_driver_shutdown != NULL &&
2022 	    !(*dev->dv_driver_shutdown)(dev, how))
2023 		return false;
2024 	return true;
2025 }
2026 
2027 bool
2028 device_pmf_driver_register(device_t dev,
2029     bool (*suspend)(device_t, pmf_qual_t),
2030     bool (*resume)(device_t, pmf_qual_t),
2031     bool (*shutdown)(device_t, int))
2032 {
2033 	dev->dv_driver_suspend = suspend;
2034 	dev->dv_driver_resume = resume;
2035 	dev->dv_driver_shutdown = shutdown;
2036 	dev->dv_flags |= DVF_POWER_HANDLERS;
2037 	return true;
2038 }
2039 
2040 static const char *
2041 curlwp_name(void)
2042 {
2043 	if (curlwp->l_name != NULL)
2044 		return curlwp->l_name;
2045 	else
2046 		return curlwp->l_proc->p_comm;
2047 }
2048 
2049 void
2050 device_pmf_driver_deregister(device_t dev)
2051 {
2052 	device_lock_t dvl = device_getlock(dev);
2053 
2054 	dev->dv_driver_suspend = NULL;
2055 	dev->dv_driver_resume = NULL;
2056 
2057 	mutex_enter(&dvl->dvl_mtx);
2058 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2059 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
2060 		/* Wake a thread that waits for the lock.  That
2061 		 * thread will fail to acquire the lock, and then
2062 		 * it will wake the next thread that waits for the
2063 		 * lock, or else it will wake us.
2064 		 */
2065 		cv_signal(&dvl->dvl_cv);
2066 		pmflock_debug(dev, __func__, __LINE__);
2067 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2068 		pmflock_debug(dev, __func__, __LINE__);
2069 	}
2070 	mutex_exit(&dvl->dvl_mtx);
2071 }
2072 
2073 bool
2074 device_pmf_driver_child_register(device_t dev)
2075 {
2076 	device_t parent = device_parent(dev);
2077 
2078 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2079 		return true;
2080 	return (*parent->dv_driver_child_register)(dev);
2081 }
2082 
2083 void
2084 device_pmf_driver_set_child_register(device_t dev,
2085     bool (*child_register)(device_t))
2086 {
2087 	dev->dv_driver_child_register = child_register;
2088 }
2089 
2090 static void
2091 pmflock_debug(device_t dev, const char *func, int line)
2092 {
2093 	device_lock_t dvl = device_getlock(dev);
2094 
2095 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n",
2096 	    func, line, curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait,
2097 	    dev->dv_flags);
2098 }
2099 
2100 static bool
2101 device_pmf_lock1(device_t dev)
2102 {
2103 	device_lock_t dvl = device_getlock(dev);
2104 
2105 	while (device_pmf_is_registered(dev) &&
2106 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
2107 		dvl->dvl_nwait++;
2108 		pmflock_debug(dev, __func__, __LINE__);
2109 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2110 		pmflock_debug(dev, __func__, __LINE__);
2111 		dvl->dvl_nwait--;
2112 	}
2113 	if (!device_pmf_is_registered(dev)) {
2114 		pmflock_debug(dev, __func__, __LINE__);
2115 		/* We could not acquire the lock, but some other thread may
2116 		 * wait for it, also.  Wake that thread.
2117 		 */
2118 		cv_signal(&dvl->dvl_cv);
2119 		return false;
2120 	}
2121 	dvl->dvl_nlock++;
2122 	dvl->dvl_holder = curlwp;
2123 	pmflock_debug(dev, __func__, __LINE__);
2124 	return true;
2125 }
2126 
2127 bool
2128 device_pmf_lock(device_t dev)
2129 {
2130 	bool rc;
2131 	device_lock_t dvl = device_getlock(dev);
2132 
2133 	mutex_enter(&dvl->dvl_mtx);
2134 	rc = device_pmf_lock1(dev);
2135 	mutex_exit(&dvl->dvl_mtx);
2136 
2137 	return rc;
2138 }
2139 
2140 void
2141 device_pmf_unlock(device_t dev)
2142 {
2143 	device_lock_t dvl = device_getlock(dev);
2144 
2145 	KASSERT(dvl->dvl_nlock > 0);
2146 	mutex_enter(&dvl->dvl_mtx);
2147 	if (--dvl->dvl_nlock == 0)
2148 		dvl->dvl_holder = NULL;
2149 	cv_signal(&dvl->dvl_cv);
2150 	pmflock_debug(dev, __func__, __LINE__);
2151 	mutex_exit(&dvl->dvl_mtx);
2152 }
2153 
2154 device_lock_t
2155 device_getlock(device_t dev)
2156 {
2157 	return &dev->dv_lock;
2158 }
2159 
2160 void *
2161 device_pmf_bus_private(device_t dev)
2162 {
2163 	return dev->dv_bus_private;
2164 }
2165 
2166 bool
2167 device_pmf_bus_suspend(device_t dev, pmf_qual_t qual)
2168 {
2169 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2170 		return true;
2171 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2172 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2173 		return false;
2174 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2175 	    dev->dv_bus_suspend != NULL &&
2176 	    !(*dev->dv_bus_suspend)(dev, qual))
2177 		return false;
2178 
2179 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2180 	return true;
2181 }
2182 
2183 bool
2184 device_pmf_bus_resume(device_t dev, pmf_qual_t qual)
2185 {
2186 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2187 		return true;
2188 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2189 	    dev->dv_bus_resume != NULL &&
2190 	    !(*dev->dv_bus_resume)(dev, qual))
2191 		return false;
2192 
2193 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2194 	return true;
2195 }
2196 
2197 bool
2198 device_pmf_bus_shutdown(device_t dev, int how)
2199 {
2200 
2201 	if (*dev->dv_bus_shutdown != NULL &&
2202 	    !(*dev->dv_bus_shutdown)(dev, how))
2203 		return false;
2204 	return true;
2205 }
2206 
2207 void
2208 device_pmf_bus_register(device_t dev, void *priv,
2209     bool (*suspend)(device_t, pmf_qual_t),
2210     bool (*resume)(device_t, pmf_qual_t),
2211     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2212 {
2213 	dev->dv_bus_private = priv;
2214 	dev->dv_bus_resume = resume;
2215 	dev->dv_bus_suspend = suspend;
2216 	dev->dv_bus_shutdown = shutdown;
2217 	dev->dv_bus_deregister = deregister;
2218 }
2219 
2220 void
2221 device_pmf_bus_deregister(device_t dev)
2222 {
2223 	if (dev->dv_bus_deregister == NULL)
2224 		return;
2225 	(*dev->dv_bus_deregister)(dev);
2226 	dev->dv_bus_private = NULL;
2227 	dev->dv_bus_suspend = NULL;
2228 	dev->dv_bus_resume = NULL;
2229 	dev->dv_bus_deregister = NULL;
2230 }
2231 
2232 void *
2233 device_pmf_class_private(device_t dev)
2234 {
2235 	return dev->dv_class_private;
2236 }
2237 
2238 bool
2239 device_pmf_class_suspend(device_t dev, pmf_qual_t qual)
2240 {
2241 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2242 		return true;
2243 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2244 	    dev->dv_class_suspend != NULL &&
2245 	    !(*dev->dv_class_suspend)(dev, qual))
2246 		return false;
2247 
2248 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2249 	return true;
2250 }
2251 
2252 bool
2253 device_pmf_class_resume(device_t dev, pmf_qual_t qual)
2254 {
2255 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2256 		return true;
2257 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2258 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2259 		return false;
2260 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2261 	    dev->dv_class_resume != NULL &&
2262 	    !(*dev->dv_class_resume)(dev, qual))
2263 		return false;
2264 
2265 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2266 	return true;
2267 }
2268 
2269 void
2270 device_pmf_class_register(device_t dev, void *priv,
2271     bool (*suspend)(device_t, pmf_qual_t),
2272     bool (*resume)(device_t, pmf_qual_t),
2273     void (*deregister)(device_t))
2274 {
2275 	dev->dv_class_private = priv;
2276 	dev->dv_class_suspend = suspend;
2277 	dev->dv_class_resume = resume;
2278 	dev->dv_class_deregister = deregister;
2279 }
2280 
2281 void
2282 device_pmf_class_deregister(device_t dev)
2283 {
2284 	if (dev->dv_class_deregister == NULL)
2285 		return;
2286 	(*dev->dv_class_deregister)(dev);
2287 	dev->dv_class_private = NULL;
2288 	dev->dv_class_suspend = NULL;
2289 	dev->dv_class_resume = NULL;
2290 	dev->dv_class_deregister = NULL;
2291 }
2292 
2293 bool
2294 device_active(device_t dev, devactive_t type)
2295 {
2296 	size_t i;
2297 
2298 	if (dev->dv_activity_count == 0)
2299 		return false;
2300 
2301 	for (i = 0; i < dev->dv_activity_count; ++i) {
2302 		if (dev->dv_activity_handlers[i] == NULL)
2303 			break;
2304 		(*dev->dv_activity_handlers[i])(dev, type);
2305 	}
2306 
2307 	return true;
2308 }
2309 
2310 bool
2311 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2312 {
2313 	void (**new_handlers)(device_t, devactive_t);
2314 	void (**old_handlers)(device_t, devactive_t);
2315 	size_t i, old_size, new_size;
2316 	int s;
2317 
2318 	old_handlers = dev->dv_activity_handlers;
2319 	old_size = dev->dv_activity_count;
2320 
2321 	for (i = 0; i < old_size; ++i) {
2322 		KASSERT(old_handlers[i] != handler);
2323 		if (old_handlers[i] == NULL) {
2324 			old_handlers[i] = handler;
2325 			return true;
2326 		}
2327 	}
2328 
2329 	new_size = old_size + 4;
2330 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
2331 
2332 	memcpy(new_handlers, old_handlers, sizeof(void *[old_size]));
2333 	new_handlers[old_size] = handler;
2334 	memset(new_handlers + old_size + 1, 0,
2335 	    sizeof(int [new_size - (old_size+1)]));
2336 
2337 	s = splhigh();
2338 	dev->dv_activity_count = new_size;
2339 	dev->dv_activity_handlers = new_handlers;
2340 	splx(s);
2341 
2342 	if (old_handlers != NULL)
2343 		kmem_free(old_handlers, sizeof(void * [old_size]));
2344 
2345 	return true;
2346 }
2347 
2348 void
2349 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2350 {
2351 	void (**old_handlers)(device_t, devactive_t);
2352 	size_t i, old_size;
2353 	int s;
2354 
2355 	old_handlers = dev->dv_activity_handlers;
2356 	old_size = dev->dv_activity_count;
2357 
2358 	for (i = 0; i < old_size; ++i) {
2359 		if (old_handlers[i] == handler)
2360 			break;
2361 		if (old_handlers[i] == NULL)
2362 			return; /* XXX panic? */
2363 	}
2364 
2365 	if (i == old_size)
2366 		return; /* XXX panic? */
2367 
2368 	for (; i < old_size - 1; ++i) {
2369 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
2370 			continue;
2371 
2372 		if (i == 0) {
2373 			s = splhigh();
2374 			dev->dv_activity_count = 0;
2375 			dev->dv_activity_handlers = NULL;
2376 			splx(s);
2377 			kmem_free(old_handlers, sizeof(void *[old_size]));
2378 		}
2379 		return;
2380 	}
2381 	old_handlers[i] = NULL;
2382 }
2383 
2384 /* Return true iff the device_t `dev' exists at generation `gen'. */
2385 static bool
2386 device_exists_at(device_t dv, devgen_t gen)
2387 {
2388 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
2389 	    dv->dv_add_gen <= gen;
2390 }
2391 
2392 static bool
2393 deviter_visits(const deviter_t *di, device_t dv)
2394 {
2395 	return device_exists_at(dv, di->di_gen);
2396 }
2397 
2398 /*
2399  * Device Iteration
2400  *
2401  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2402  *     each device_t's in the device tree.
2403  *
2404  * deviter_init(di, flags): initialize the device iterator `di'
2405  *     to "walk" the device tree.  deviter_next(di) will return
2406  *     the first device_t in the device tree, or NULL if there are
2407  *     no devices.
2408  *
2409  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2410  *     caller intends to modify the device tree by calling
2411  *     config_detach(9) on devices in the order that the iterator
2412  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2413  *     nearest the "root" of the device tree to be returned, first;
2414  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2415  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2416  *     indicating both that deviter_init() should not respect any
2417  *     locks on the device tree, and that deviter_next(di) may run
2418  *     in more than one LWP before the walk has finished.
2419  *
2420  *     Only one DEVITER_F_RW iterator may be in the device tree at
2421  *     once.
2422  *
2423  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2424  *
2425  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2426  *     DEVITER_F_LEAVES_FIRST are used in combination.
2427  *
2428  * deviter_first(di, flags): initialize the device iterator `di'
2429  *     and return the first device_t in the device tree, or NULL
2430  *     if there are no devices.  The statement
2431  *
2432  *         dv = deviter_first(di);
2433  *
2434  *     is shorthand for
2435  *
2436  *         deviter_init(di);
2437  *         dv = deviter_next(di);
2438  *
2439  * deviter_next(di): return the next device_t in the device tree,
2440  *     or NULL if there are no more devices.  deviter_next(di)
2441  *     is undefined if `di' was not initialized with deviter_init() or
2442  *     deviter_first().
2443  *
2444  * deviter_release(di): stops iteration (subsequent calls to
2445  *     deviter_next() will return NULL), releases any locks and
2446  *     resources held by the device iterator.
2447  *
2448  * Device iteration does not return device_t's in any particular
2449  * order.  An iterator will never return the same device_t twice.
2450  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2451  * is called repeatedly on the same `di', it will eventually return
2452  * NULL.  It is ok to attach/detach devices during device iteration.
2453  */
2454 void
2455 deviter_init(deviter_t *di, deviter_flags_t flags)
2456 {
2457 	device_t dv;
2458 	int s;
2459 
2460 	memset(di, 0, sizeof(*di));
2461 
2462 	s = config_alldevs_lock();
2463 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
2464 		flags |= DEVITER_F_RW;
2465 
2466 	if ((flags & DEVITER_F_RW) != 0)
2467 		alldevs_nwrite++;
2468 	else
2469 		alldevs_nread++;
2470 	di->di_gen = alldevs_gen++;
2471 	config_alldevs_unlock(s);
2472 
2473 	di->di_flags = flags;
2474 
2475 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2476 	case DEVITER_F_LEAVES_FIRST:
2477 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2478 			if (!deviter_visits(di, dv))
2479 				continue;
2480 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2481 		}
2482 		break;
2483 	case DEVITER_F_ROOT_FIRST:
2484 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2485 			if (!deviter_visits(di, dv))
2486 				continue;
2487 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2488 		}
2489 		break;
2490 	default:
2491 		break;
2492 	}
2493 
2494 	deviter_reinit(di);
2495 }
2496 
2497 static void
2498 deviter_reinit(deviter_t *di)
2499 {
2500 	if ((di->di_flags & DEVITER_F_RW) != 0)
2501 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2502 	else
2503 		di->di_prev = TAILQ_FIRST(&alldevs);
2504 }
2505 
2506 device_t
2507 deviter_first(deviter_t *di, deviter_flags_t flags)
2508 {
2509 	deviter_init(di, flags);
2510 	return deviter_next(di);
2511 }
2512 
2513 static device_t
2514 deviter_next2(deviter_t *di)
2515 {
2516 	device_t dv;
2517 
2518 	dv = di->di_prev;
2519 
2520 	if (dv == NULL)
2521 		return NULL;
2522 
2523 	if ((di->di_flags & DEVITER_F_RW) != 0)
2524 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2525 	else
2526 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2527 
2528 	return dv;
2529 }
2530 
2531 static device_t
2532 deviter_next1(deviter_t *di)
2533 {
2534 	device_t dv;
2535 
2536 	do {
2537 		dv = deviter_next2(di);
2538 	} while (dv != NULL && !deviter_visits(di, dv));
2539 
2540 	return dv;
2541 }
2542 
2543 device_t
2544 deviter_next(deviter_t *di)
2545 {
2546 	device_t dv = NULL;
2547 
2548 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2549 	case 0:
2550 		return deviter_next1(di);
2551 	case DEVITER_F_LEAVES_FIRST:
2552 		while (di->di_curdepth >= 0) {
2553 			if ((dv = deviter_next1(di)) == NULL) {
2554 				di->di_curdepth--;
2555 				deviter_reinit(di);
2556 			} else if (dv->dv_depth == di->di_curdepth)
2557 				break;
2558 		}
2559 		return dv;
2560 	case DEVITER_F_ROOT_FIRST:
2561 		while (di->di_curdepth <= di->di_maxdepth) {
2562 			if ((dv = deviter_next1(di)) == NULL) {
2563 				di->di_curdepth++;
2564 				deviter_reinit(di);
2565 			} else if (dv->dv_depth == di->di_curdepth)
2566 				break;
2567 		}
2568 		return dv;
2569 	default:
2570 		return NULL;
2571 	}
2572 }
2573 
2574 void
2575 deviter_release(deviter_t *di)
2576 {
2577 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2578 	int s;
2579 
2580 	s = config_alldevs_lock();
2581 	if (rw)
2582 		--alldevs_nwrite;
2583 	else
2584 		--alldevs_nread;
2585 	/* XXX wake a garbage-collection thread */
2586 	config_alldevs_unlock(s);
2587 }
2588 
2589 const char *
2590 cfdata_ifattr(const struct cfdata *cf)
2591 {
2592 	return cf->cf_pspec->cfp_iattr;
2593 }
2594 
2595 bool
2596 ifattr_match(const char *snull, const char *t)
2597 {
2598 	return (snull == NULL) || strcmp(snull, t) == 0;
2599 }
2600 
2601 void
2602 null_childdetached(device_t self, device_t child)
2603 {
2604 	/* do nothing */
2605 }
2606 
2607 static void
2608 sysctl_detach_setup(struct sysctllog **clog)
2609 {
2610 	const struct sysctlnode *node = NULL;
2611 
2612 	sysctl_createv(clog, 0, NULL, &node,
2613 		CTLFLAG_PERMANENT,
2614 		CTLTYPE_NODE, "kern", NULL,
2615 		NULL, 0, NULL, 0,
2616 		CTL_KERN, CTL_EOL);
2617 
2618 	if (node == NULL)
2619 		return;
2620 
2621 	sysctl_createv(clog, 0, &node, NULL,
2622 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
2623 		CTLTYPE_INT, "detachall",
2624 		SYSCTL_DESCR("Detach all devices at shutdown"),
2625 		NULL, 0, &detachall, 0,
2626 		CTL_CREATE, CTL_EOL);
2627 }
2628