xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /* $NetBSD: subr_autoconf.c,v 1.273 2020/08/01 11:18:26 jdolecek 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 1.273 2020/08/01 11:18:26 jdolecek Exp $");
81 
82 #ifdef _KERNEL_OPT
83 #include "opt_ddb.h"
84 #include "drvctl.h"
85 #endif
86 
87 #include <sys/param.h>
88 #include <sys/device.h>
89 #include <sys/disklabel.h>
90 #include <sys/conf.h>
91 #include <sys/kauth.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/mount.h>
102 #include <sys/namei.h>
103 #include <sys/unistd.h>
104 #include <sys/fcntl.h>
105 #include <sys/lockf.h>
106 #include <sys/callout.h>
107 #include <sys/devmon.h>
108 #include <sys/cpu.h>
109 #include <sys/sysctl.h>
110 
111 #include <sys/disk.h>
112 
113 #include <sys/rndsource.h>
114 
115 #include <machine/limits.h>
116 
117 /*
118  * Autoconfiguration subroutines.
119  */
120 
121 /*
122  * Device autoconfiguration timings are mixed into the entropy pool.
123  */
124 static krndsource_t rnd_autoconf_source;
125 
126 /*
127  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
128  * devices and drivers are found via these tables.
129  */
130 extern struct cfdata cfdata[];
131 extern const short cfroots[];
132 
133 /*
134  * List of all cfdriver structures.  We use this to detect duplicates
135  * when other cfdrivers are loaded.
136  */
137 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
138 extern struct cfdriver * const cfdriver_list_initial[];
139 
140 /*
141  * Initial list of cfattach's.
142  */
143 extern const struct cfattachinit cfattachinit[];
144 
145 /*
146  * List of cfdata tables.  We always have one such list -- the one
147  * built statically when the kernel was configured.
148  */
149 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
150 static struct cftable initcftable;
151 
152 #define	ROOT ((device_t)NULL)
153 
154 struct matchinfo {
155 	cfsubmatch_t fn;
156 	device_t parent;
157 	const int *locs;
158 	void	*aux;
159 	struct	cfdata *match;
160 	int	pri;
161 };
162 
163 struct alldevs_foray {
164 	int			af_s;
165 	struct devicelist	af_garbage;
166 };
167 
168 static char *number(char *, int);
169 static void mapply(struct matchinfo *, cfdata_t);
170 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
171 static void config_devdelete(device_t);
172 static void config_devunlink(device_t, struct devicelist *);
173 static void config_makeroom(int, struct cfdriver *);
174 static void config_devlink(device_t);
175 static void config_alldevs_enter(struct alldevs_foray *);
176 static void config_alldevs_exit(struct alldevs_foray *);
177 static void config_add_attrib_dict(device_t);
178 
179 static void config_collect_garbage(struct devicelist *);
180 static void config_dump_garbage(struct devicelist *);
181 
182 static void pmflock_debug(device_t, const char *, int);
183 
184 static device_t deviter_next1(deviter_t *);
185 static void deviter_reinit(deviter_t *);
186 
187 struct deferred_config {
188 	TAILQ_ENTRY(deferred_config) dc_queue;
189 	device_t dc_dev;
190 	void (*dc_func)(device_t);
191 };
192 
193 TAILQ_HEAD(deferred_config_head, deferred_config);
194 
195 static struct deferred_config_head deferred_config_queue =
196 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
197 static struct deferred_config_head interrupt_config_queue =
198 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
199 static int interrupt_config_threads = 8;
200 static struct deferred_config_head mountroot_config_queue =
201 	TAILQ_HEAD_INITIALIZER(mountroot_config_queue);
202 static int mountroot_config_threads = 2;
203 static lwp_t **mountroot_config_lwpids;
204 static size_t mountroot_config_lwpids_size;
205 bool root_is_mounted = false;
206 
207 static void config_process_deferred(struct deferred_config_head *, device_t);
208 
209 /* Hooks to finalize configuration once all real devices have been found. */
210 struct finalize_hook {
211 	TAILQ_ENTRY(finalize_hook) f_list;
212 	int (*f_func)(device_t);
213 	device_t f_dev;
214 };
215 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
216 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
217 static int config_finalize_done;
218 
219 /* list of all devices */
220 static struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
221 static kmutex_t alldevs_lock __cacheline_aligned;
222 static devgen_t alldevs_gen = 1;
223 static int alldevs_nread = 0;
224 static int alldevs_nwrite = 0;
225 static bool alldevs_garbage = false;
226 
227 static int config_pending;		/* semaphore for mountroot */
228 static kmutex_t config_misc_lock;
229 static kcondvar_t config_misc_cv;
230 
231 static bool detachall = false;
232 
233 #define	STREQ(s1, s2)			\
234 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
235 
236 static bool config_initialized = false;	/* config_init() has been called. */
237 
238 static int config_do_twiddle;
239 static callout_t config_twiddle_ch;
240 
241 static void sysctl_detach_setup(struct sysctllog **);
242 
243 int no_devmon_insert(const char *, prop_dictionary_t);
244 int (*devmon_insert_vec)(const char *, prop_dictionary_t) = no_devmon_insert;
245 
246 typedef int (*cfdriver_fn)(struct cfdriver *);
247 static int
248 frob_cfdrivervec(struct cfdriver * const *cfdriverv,
249 	cfdriver_fn drv_do, cfdriver_fn drv_undo,
250 	const char *style, bool dopanic)
251 {
252 	void (*pr)(const char *, ...) __printflike(1, 2) =
253 	    dopanic ? panic : printf;
254 	int i, error = 0, e2 __diagused;
255 
256 	for (i = 0; cfdriverv[i] != NULL; i++) {
257 		if ((error = drv_do(cfdriverv[i])) != 0) {
258 			pr("configure: `%s' driver %s failed: %d",
259 			    cfdriverv[i]->cd_name, style, error);
260 			goto bad;
261 		}
262 	}
263 
264 	KASSERT(error == 0);
265 	return 0;
266 
267  bad:
268 	printf("\n");
269 	for (i--; i >= 0; i--) {
270 		e2 = drv_undo(cfdriverv[i]);
271 		KASSERT(e2 == 0);
272 	}
273 
274 	return error;
275 }
276 
277 typedef int (*cfattach_fn)(const char *, struct cfattach *);
278 static int
279 frob_cfattachvec(const struct cfattachinit *cfattachv,
280 	cfattach_fn att_do, cfattach_fn att_undo,
281 	const char *style, bool dopanic)
282 {
283 	const struct cfattachinit *cfai = NULL;
284 	void (*pr)(const char *, ...) __printflike(1, 2) =
285 	    dopanic ? panic : printf;
286 	int j = 0, error = 0, e2 __diagused;
287 
288 	for (cfai = &cfattachv[0]; cfai->cfai_name != NULL; cfai++) {
289 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
290 			if ((error = att_do(cfai->cfai_name,
291 			    cfai->cfai_list[j])) != 0) {
292 				pr("configure: attachment `%s' "
293 				    "of `%s' driver %s failed: %d",
294 				    cfai->cfai_list[j]->ca_name,
295 				    cfai->cfai_name, style, error);
296 				goto bad;
297 			}
298 		}
299 	}
300 
301 	KASSERT(error == 0);
302 	return 0;
303 
304  bad:
305 	/*
306 	 * Rollback in reverse order.  dunno if super-important, but
307 	 * do that anyway.  Although the code looks a little like
308 	 * someone did a little integration (in the math sense).
309 	 */
310 	printf("\n");
311 	if (cfai) {
312 		bool last;
313 
314 		for (last = false; last == false; ) {
315 			if (cfai == &cfattachv[0])
316 				last = true;
317 			for (j--; j >= 0; j--) {
318 				e2 = att_undo(cfai->cfai_name,
319 				    cfai->cfai_list[j]);
320 				KASSERT(e2 == 0);
321 			}
322 			if (!last) {
323 				cfai--;
324 				for (j = 0; cfai->cfai_list[j] != NULL; j++)
325 					;
326 			}
327 		}
328 	}
329 
330 	return error;
331 }
332 
333 /*
334  * Initialize the autoconfiguration data structures.  Normally this
335  * is done by configure(), but some platforms need to do this very
336  * early (to e.g. initialize the console).
337  */
338 void
339 config_init(void)
340 {
341 
342 	KASSERT(config_initialized == false);
343 
344 	mutex_init(&alldevs_lock, MUTEX_DEFAULT, IPL_VM);
345 
346 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
347 	cv_init(&config_misc_cv, "cfgmisc");
348 
349 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
350 
351 	frob_cfdrivervec(cfdriver_list_initial,
352 	    config_cfdriver_attach, NULL, "bootstrap", true);
353 	frob_cfattachvec(cfattachinit,
354 	    config_cfattach_attach, NULL, "bootstrap", true);
355 
356 	initcftable.ct_cfdata = cfdata;
357 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
358 
359 	rnd_attach_source(&rnd_autoconf_source, "autoconf", RND_TYPE_UNKNOWN,
360 	    RND_FLAG_COLLECT_TIME);
361 
362 	config_initialized = true;
363 }
364 
365 /*
366  * Init or fini drivers and attachments.  Either all or none
367  * are processed (via rollback).  It would be nice if this were
368  * atomic to outside consumers, but with the current state of
369  * locking ...
370  */
371 int
372 config_init_component(struct cfdriver * const *cfdriverv,
373 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
374 {
375 	int error;
376 
377 	if ((error = frob_cfdrivervec(cfdriverv,
378 	    config_cfdriver_attach, config_cfdriver_detach, "init", false))!= 0)
379 		return error;
380 	if ((error = frob_cfattachvec(cfattachv,
381 	    config_cfattach_attach, config_cfattach_detach,
382 	    "init", false)) != 0) {
383 		frob_cfdrivervec(cfdriverv,
384 	            config_cfdriver_detach, NULL, "init rollback", true);
385 		return error;
386 	}
387 	if ((error = config_cfdata_attach(cfdatav, 1)) != 0) {
388 		frob_cfattachvec(cfattachv,
389 		    config_cfattach_detach, NULL, "init rollback", true);
390 		frob_cfdrivervec(cfdriverv,
391 	            config_cfdriver_detach, NULL, "init rollback", true);
392 		return error;
393 	}
394 
395 	return 0;
396 }
397 
398 int
399 config_fini_component(struct cfdriver * const *cfdriverv,
400 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
401 {
402 	int error;
403 
404 	if ((error = config_cfdata_detach(cfdatav)) != 0)
405 		return error;
406 	if ((error = frob_cfattachvec(cfattachv,
407 	    config_cfattach_detach, config_cfattach_attach,
408 	    "fini", false)) != 0) {
409 		if (config_cfdata_attach(cfdatav, 0) != 0)
410 			panic("config_cfdata fini rollback failed");
411 		return error;
412 	}
413 	if ((error = frob_cfdrivervec(cfdriverv,
414 	    config_cfdriver_detach, config_cfdriver_attach,
415 	    "fini", false)) != 0) {
416 		frob_cfattachvec(cfattachv,
417 	            config_cfattach_attach, NULL, "fini rollback", true);
418 		if (config_cfdata_attach(cfdatav, 0) != 0)
419 			panic("config_cfdata fini rollback failed");
420 		return error;
421 	}
422 
423 	return 0;
424 }
425 
426 void
427 config_init_mi(void)
428 {
429 
430 	if (!config_initialized)
431 		config_init();
432 
433 	sysctl_detach_setup(NULL);
434 }
435 
436 void
437 config_deferred(device_t dev)
438 {
439 	config_process_deferred(&deferred_config_queue, dev);
440 	config_process_deferred(&interrupt_config_queue, dev);
441 	config_process_deferred(&mountroot_config_queue, dev);
442 }
443 
444 static void
445 config_interrupts_thread(void *cookie)
446 {
447 	struct deferred_config *dc;
448 	device_t dev;
449 
450 	mutex_enter(&config_misc_lock);
451 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
452 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
453 		mutex_exit(&config_misc_lock);
454 
455 		dev = dc->dc_dev;
456 		(*dc->dc_func)(dev);
457 		if (!device_pmf_is_registered(dev))
458 			aprint_debug_dev(dev,
459 			    "WARNING: power management not supported\n");
460 		config_pending_decr(dev);
461 		kmem_free(dc, sizeof(*dc));
462 
463 		mutex_enter(&config_misc_lock);
464 		dev->dv_flags &= ~DVF_ATTACH_INPROGRESS;
465 	}
466 	mutex_exit(&config_misc_lock);
467 
468 	kthread_exit(0);
469 }
470 
471 void
472 config_create_interruptthreads(void)
473 {
474 	int i;
475 
476 	for (i = 0; i < interrupt_config_threads; i++) {
477 		(void)kthread_create(PRI_NONE, 0/*XXXSMP */, NULL,
478 		    config_interrupts_thread, NULL, NULL, "configintr");
479 	}
480 }
481 
482 static void
483 config_mountroot_thread(void *cookie)
484 {
485 	struct deferred_config *dc;
486 
487 	mutex_enter(&config_misc_lock);
488 	while ((dc = TAILQ_FIRST(&mountroot_config_queue)) != NULL) {
489 		TAILQ_REMOVE(&mountroot_config_queue, dc, dc_queue);
490 		mutex_exit(&config_misc_lock);
491 
492 		(*dc->dc_func)(dc->dc_dev);
493 		kmem_free(dc, sizeof(*dc));
494 
495 		mutex_enter(&config_misc_lock);
496 	}
497 	mutex_exit(&config_misc_lock);
498 
499 	kthread_exit(0);
500 }
501 
502 void
503 config_create_mountrootthreads(void)
504 {
505 	int i;
506 
507 	if (!root_is_mounted)
508 		root_is_mounted = true;
509 
510 	mountroot_config_lwpids_size = sizeof(mountroot_config_lwpids) *
511 				       mountroot_config_threads;
512 	mountroot_config_lwpids = kmem_alloc(mountroot_config_lwpids_size,
513 					     KM_NOSLEEP);
514 	KASSERT(mountroot_config_lwpids);
515 	for (i = 0; i < mountroot_config_threads; i++) {
516 		mountroot_config_lwpids[i] = 0;
517 		(void)kthread_create(PRI_NONE, KTHREAD_MUSTJOIN/* XXXSMP */,
518 				     NULL, config_mountroot_thread, NULL,
519 				     &mountroot_config_lwpids[i],
520 				     "configroot");
521 	}
522 }
523 
524 void
525 config_finalize_mountroot(void)
526 {
527 	int i, error;
528 
529 	for (i = 0; i < mountroot_config_threads; i++) {
530 		if (mountroot_config_lwpids[i] == 0)
531 			continue;
532 
533 		error = kthread_join(mountroot_config_lwpids[i]);
534 		if (error)
535 			printf("%s: thread %x joined with error %d\n",
536 			       __func__, i, error);
537 	}
538 	kmem_free(mountroot_config_lwpids, mountroot_config_lwpids_size);
539 }
540 
541 /*
542  * Announce device attach/detach to userland listeners.
543  */
544 
545 int
546 no_devmon_insert(const char *name, prop_dictionary_t p)
547 {
548 
549 	return ENODEV;
550 }
551 
552 static void
553 devmon_report_device(device_t dev, bool isattach)
554 {
555 	prop_dictionary_t ev, dict = device_properties(dev);
556 	const char *parent;
557 	const char *what;
558 	const char *where;
559 	device_t pdev = device_parent(dev);
560 
561 	/* If currently no drvctl device, just return */
562 	if (devmon_insert_vec == no_devmon_insert)
563 		return;
564 
565 	ev = prop_dictionary_create();
566 	if (ev == NULL)
567 		return;
568 
569 	what = (isattach ? "device-attach" : "device-detach");
570 	parent = (pdev == NULL ? "root" : device_xname(pdev));
571 	if (prop_dictionary_get_string(dict, "location", &where)) {
572 		prop_dictionary_set_string(ev, "location", where);
573 		aprint_debug("ev: %s %s at %s in [%s]\n",
574 		    what, device_xname(dev), parent, where);
575 	}
576 	if (!prop_dictionary_set_string(ev, "device", device_xname(dev)) ||
577 	    !prop_dictionary_set_string(ev, "parent", parent)) {
578 		prop_object_release(ev);
579 		return;
580 	}
581 
582 	if ((*devmon_insert_vec)(what, ev) != 0)
583 		prop_object_release(ev);
584 }
585 
586 /*
587  * Add a cfdriver to the system.
588  */
589 int
590 config_cfdriver_attach(struct cfdriver *cd)
591 {
592 	struct cfdriver *lcd;
593 
594 	/* Make sure this driver isn't already in the system. */
595 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
596 		if (STREQ(lcd->cd_name, cd->cd_name))
597 			return EEXIST;
598 	}
599 
600 	LIST_INIT(&cd->cd_attach);
601 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
602 
603 	return 0;
604 }
605 
606 /*
607  * Remove a cfdriver from the system.
608  */
609 int
610 config_cfdriver_detach(struct cfdriver *cd)
611 {
612 	struct alldevs_foray af;
613 	int i, rc = 0;
614 
615 	config_alldevs_enter(&af);
616 	/* Make sure there are no active instances. */
617 	for (i = 0; i < cd->cd_ndevs; i++) {
618 		if (cd->cd_devs[i] != NULL) {
619 			rc = EBUSY;
620 			break;
621 		}
622 	}
623 	config_alldevs_exit(&af);
624 
625 	if (rc != 0)
626 		return rc;
627 
628 	/* ...and no attachments loaded. */
629 	if (LIST_EMPTY(&cd->cd_attach) == 0)
630 		return EBUSY;
631 
632 	LIST_REMOVE(cd, cd_list);
633 
634 	KASSERT(cd->cd_devs == NULL);
635 
636 	return 0;
637 }
638 
639 /*
640  * Look up a cfdriver by name.
641  */
642 struct cfdriver *
643 config_cfdriver_lookup(const char *name)
644 {
645 	struct cfdriver *cd;
646 
647 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
648 		if (STREQ(cd->cd_name, name))
649 			return cd;
650 	}
651 
652 	return NULL;
653 }
654 
655 /*
656  * Add a cfattach to the specified driver.
657  */
658 int
659 config_cfattach_attach(const char *driver, struct cfattach *ca)
660 {
661 	struct cfattach *lca;
662 	struct cfdriver *cd;
663 
664 	cd = config_cfdriver_lookup(driver);
665 	if (cd == NULL)
666 		return ESRCH;
667 
668 	/* Make sure this attachment isn't already on this driver. */
669 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
670 		if (STREQ(lca->ca_name, ca->ca_name))
671 			return EEXIST;
672 	}
673 
674 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
675 
676 	return 0;
677 }
678 
679 /*
680  * Remove a cfattach from the specified driver.
681  */
682 int
683 config_cfattach_detach(const char *driver, struct cfattach *ca)
684 {
685 	struct alldevs_foray af;
686 	struct cfdriver *cd;
687 	device_t dev;
688 	int i, rc = 0;
689 
690 	cd = config_cfdriver_lookup(driver);
691 	if (cd == NULL)
692 		return ESRCH;
693 
694 	config_alldevs_enter(&af);
695 	/* Make sure there are no active instances. */
696 	for (i = 0; i < cd->cd_ndevs; i++) {
697 		if ((dev = cd->cd_devs[i]) == NULL)
698 			continue;
699 		if (dev->dv_cfattach == ca) {
700 			rc = EBUSY;
701 			break;
702 		}
703 	}
704 	config_alldevs_exit(&af);
705 
706 	if (rc != 0)
707 		return rc;
708 
709 	LIST_REMOVE(ca, ca_list);
710 
711 	return 0;
712 }
713 
714 /*
715  * Look up a cfattach by name.
716  */
717 static struct cfattach *
718 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
719 {
720 	struct cfattach *ca;
721 
722 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
723 		if (STREQ(ca->ca_name, atname))
724 			return ca;
725 	}
726 
727 	return NULL;
728 }
729 
730 /*
731  * Look up a cfattach by driver/attachment name.
732  */
733 struct cfattach *
734 config_cfattach_lookup(const char *name, const char *atname)
735 {
736 	struct cfdriver *cd;
737 
738 	cd = config_cfdriver_lookup(name);
739 	if (cd == NULL)
740 		return NULL;
741 
742 	return config_cfattach_lookup_cd(cd, atname);
743 }
744 
745 /*
746  * Apply the matching function and choose the best.  This is used
747  * a few times and we want to keep the code small.
748  */
749 static void
750 mapply(struct matchinfo *m, cfdata_t cf)
751 {
752 	int pri;
753 
754 	if (m->fn != NULL) {
755 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
756 	} else {
757 		pri = config_match(m->parent, cf, m->aux);
758 	}
759 	if (pri > m->pri) {
760 		m->match = cf;
761 		m->pri = pri;
762 	}
763 }
764 
765 int
766 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
767 {
768 	const struct cfiattrdata *ci;
769 	const struct cflocdesc *cl;
770 	int nlocs, i;
771 
772 	ci = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
773 	KASSERT(ci);
774 	nlocs = ci->ci_loclen;
775 	KASSERT(!nlocs || locs);
776 	for (i = 0; i < nlocs; i++) {
777 		cl = &ci->ci_locdesc[i];
778 		if (cl->cld_defaultstr != NULL &&
779 		    cf->cf_loc[i] == cl->cld_default)
780 			continue;
781 		if (cf->cf_loc[i] == locs[i])
782 			continue;
783 		return 0;
784 	}
785 
786 	return config_match(parent, cf, aux);
787 }
788 
789 /*
790  * Helper function: check whether the driver supports the interface attribute
791  * and return its descriptor structure.
792  */
793 static const struct cfiattrdata *
794 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
795 {
796 	const struct cfiattrdata * const *cpp;
797 
798 	if (cd->cd_attrs == NULL)
799 		return 0;
800 
801 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
802 		if (STREQ((*cpp)->ci_name, ia)) {
803 			/* Match. */
804 			return *cpp;
805 		}
806 	}
807 	return 0;
808 }
809 
810 /*
811  * Lookup an interface attribute description by name.
812  * If the driver is given, consider only its supported attributes.
813  */
814 const struct cfiattrdata *
815 cfiattr_lookup(const char *name, const struct cfdriver *cd)
816 {
817 	const struct cfdriver *d;
818 	const struct cfiattrdata *ia;
819 
820 	if (cd)
821 		return cfdriver_get_iattr(cd, name);
822 
823 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
824 		ia = cfdriver_get_iattr(d, name);
825 		if (ia)
826 			return ia;
827 	}
828 	return 0;
829 }
830 
831 /*
832  * Determine if `parent' is a potential parent for a device spec based
833  * on `cfp'.
834  */
835 static int
836 cfparent_match(const device_t parent, const struct cfparent *cfp)
837 {
838 	struct cfdriver *pcd;
839 
840 	/* We don't match root nodes here. */
841 	if (cfp == NULL)
842 		return 0;
843 
844 	pcd = parent->dv_cfdriver;
845 	KASSERT(pcd != NULL);
846 
847 	/*
848 	 * First, ensure this parent has the correct interface
849 	 * attribute.
850 	 */
851 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
852 		return 0;
853 
854 	/*
855 	 * If no specific parent device instance was specified (i.e.
856 	 * we're attaching to the attribute only), we're done!
857 	 */
858 	if (cfp->cfp_parent == NULL)
859 		return 1;
860 
861 	/*
862 	 * Check the parent device's name.
863 	 */
864 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
865 		return 0;	/* not the same parent */
866 
867 	/*
868 	 * Make sure the unit number matches.
869 	 */
870 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
871 	    cfp->cfp_unit == parent->dv_unit)
872 		return 1;
873 
874 	/* Unit numbers don't match. */
875 	return 0;
876 }
877 
878 /*
879  * Helper for config_cfdata_attach(): check all devices whether it could be
880  * parent any attachment in the config data table passed, and rescan.
881  */
882 static void
883 rescan_with_cfdata(const struct cfdata *cf)
884 {
885 	device_t d;
886 	const struct cfdata *cf1;
887 	deviter_t di;
888 
889 
890 	/*
891 	 * "alldevs" is likely longer than a modules's cfdata, so make it
892 	 * the outer loop.
893 	 */
894 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
895 
896 		if (!(d->dv_cfattach->ca_rescan))
897 			continue;
898 
899 		for (cf1 = cf; cf1->cf_name; cf1++) {
900 
901 			if (!cfparent_match(d, cf1->cf_pspec))
902 				continue;
903 
904 			(*d->dv_cfattach->ca_rescan)(d,
905 				cfdata_ifattr(cf1), cf1->cf_loc);
906 
907 			config_deferred(d);
908 		}
909 	}
910 	deviter_release(&di);
911 }
912 
913 /*
914  * Attach a supplemental config data table and rescan potential
915  * parent devices if required.
916  */
917 int
918 config_cfdata_attach(cfdata_t cf, int scannow)
919 {
920 	struct cftable *ct;
921 
922 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
923 	ct->ct_cfdata = cf;
924 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
925 
926 	if (scannow)
927 		rescan_with_cfdata(cf);
928 
929 	return 0;
930 }
931 
932 /*
933  * Helper for config_cfdata_detach: check whether a device is
934  * found through any attachment in the config data table.
935  */
936 static int
937 dev_in_cfdata(device_t d, cfdata_t cf)
938 {
939 	const struct cfdata *cf1;
940 
941 	for (cf1 = cf; cf1->cf_name; cf1++)
942 		if (d->dv_cfdata == cf1)
943 			return 1;
944 
945 	return 0;
946 }
947 
948 /*
949  * Detach a supplemental config data table. Detach all devices found
950  * through that table (and thus keeping references to it) before.
951  */
952 int
953 config_cfdata_detach(cfdata_t cf)
954 {
955 	device_t d;
956 	int error = 0;
957 	struct cftable *ct;
958 	deviter_t di;
959 
960 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
961 	     d = deviter_next(&di)) {
962 		if (!dev_in_cfdata(d, cf))
963 			continue;
964 		if ((error = config_detach(d, 0)) != 0)
965 			break;
966 	}
967 	deviter_release(&di);
968 	if (error) {
969 		aprint_error_dev(d, "unable to detach instance\n");
970 		return error;
971 	}
972 
973 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
974 		if (ct->ct_cfdata == cf) {
975 			TAILQ_REMOVE(&allcftables, ct, ct_list);
976 			kmem_free(ct, sizeof(*ct));
977 			return 0;
978 		}
979 	}
980 
981 	/* not found -- shouldn't happen */
982 	return EINVAL;
983 }
984 
985 /*
986  * Invoke the "match" routine for a cfdata entry on behalf of
987  * an external caller, usually a "submatch" routine.
988  */
989 int
990 config_match(device_t parent, cfdata_t cf, void *aux)
991 {
992 	struct cfattach *ca;
993 
994 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
995 	if (ca == NULL) {
996 		/* No attachment for this entry, oh well. */
997 		return 0;
998 	}
999 
1000 	return (*ca->ca_match)(parent, cf, aux);
1001 }
1002 
1003 /*
1004  * Iterate over all potential children of some device, calling the given
1005  * function (default being the child's match function) for each one.
1006  * Nonzero returns are matches; the highest value returned is considered
1007  * the best match.  Return the `found child' if we got a match, or NULL
1008  * otherwise.  The `aux' pointer is simply passed on through.
1009  *
1010  * Note that this function is designed so that it can be used to apply
1011  * an arbitrary function to all potential children (its return value
1012  * can be ignored).
1013  */
1014 cfdata_t
1015 config_search_loc(cfsubmatch_t fn, device_t parent,
1016 		  const char *ifattr, const int *locs, void *aux)
1017 {
1018 	struct cftable *ct;
1019 	cfdata_t cf;
1020 	struct matchinfo m;
1021 
1022 	KASSERT(config_initialized);
1023 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
1024 
1025 	m.fn = fn;
1026 	m.parent = parent;
1027 	m.locs = locs;
1028 	m.aux = aux;
1029 	m.match = NULL;
1030 	m.pri = 0;
1031 
1032 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1033 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1034 
1035 			/* We don't match root nodes here. */
1036 			if (!cf->cf_pspec)
1037 				continue;
1038 
1039 			/*
1040 			 * Skip cf if no longer eligible, otherwise scan
1041 			 * through parents for one matching `parent', and
1042 			 * try match function.
1043 			 */
1044 			if (cf->cf_fstate == FSTATE_FOUND)
1045 				continue;
1046 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
1047 			    cf->cf_fstate == FSTATE_DSTAR)
1048 				continue;
1049 
1050 			/*
1051 			 * If an interface attribute was specified,
1052 			 * consider only children which attach to
1053 			 * that attribute.
1054 			 */
1055 			if (ifattr && !STREQ(ifattr, cfdata_ifattr(cf)))
1056 				continue;
1057 
1058 			if (cfparent_match(parent, cf->cf_pspec))
1059 				mapply(&m, cf);
1060 		}
1061 	}
1062 	return m.match;
1063 }
1064 
1065 cfdata_t
1066 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
1067     void *aux)
1068 {
1069 
1070 	return config_search_loc(fn, parent, ifattr, NULL, aux);
1071 }
1072 
1073 /*
1074  * Find the given root device.
1075  * This is much like config_search, but there is no parent.
1076  * Don't bother with multiple cfdata tables; the root node
1077  * must always be in the initial table.
1078  */
1079 cfdata_t
1080 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
1081 {
1082 	cfdata_t cf;
1083 	const short *p;
1084 	struct matchinfo m;
1085 
1086 	m.fn = fn;
1087 	m.parent = ROOT;
1088 	m.aux = aux;
1089 	m.match = NULL;
1090 	m.pri = 0;
1091 	m.locs = 0;
1092 	/*
1093 	 * Look at root entries for matching name.  We do not bother
1094 	 * with found-state here since only one root should ever be
1095 	 * searched (and it must be done first).
1096 	 */
1097 	for (p = cfroots; *p >= 0; p++) {
1098 		cf = &cfdata[*p];
1099 		if (strcmp(cf->cf_name, rootname) == 0)
1100 			mapply(&m, cf);
1101 	}
1102 	return m.match;
1103 }
1104 
1105 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
1106 
1107 /*
1108  * The given `aux' argument describes a device that has been found
1109  * on the given parent, but not necessarily configured.  Locate the
1110  * configuration data for that device (using the submatch function
1111  * provided, or using candidates' cd_match configuration driver
1112  * functions) and attach it, and return its device_t.  If the device was
1113  * not configured, call the given `print' function and return NULL.
1114  */
1115 device_t
1116 config_found_sm_loc(device_t parent,
1117 		const char *ifattr, const int *locs, void *aux,
1118 		cfprint_t print, cfsubmatch_t submatch)
1119 {
1120 	cfdata_t cf;
1121 
1122 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
1123 		return(config_attach_loc(parent, cf, locs, aux, print));
1124 	if (print) {
1125 		if (config_do_twiddle && cold)
1126 			twiddle();
1127 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
1128 	}
1129 
1130 	/*
1131 	 * This has the effect of mixing in a single timestamp to the
1132 	 * entropy pool.  Experiments indicate the estimator will almost
1133 	 * always attribute one bit of entropy to this sample; analysis
1134 	 * of device attach/detach timestamps on FreeBSD indicates 4
1135 	 * bits of entropy/sample so this seems appropriately conservative.
1136 	 */
1137 	rnd_add_uint32(&rnd_autoconf_source, 0);
1138 	return NULL;
1139 }
1140 
1141 device_t
1142 config_found_ia(device_t parent, const char *ifattr, void *aux,
1143     cfprint_t print)
1144 {
1145 
1146 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
1147 }
1148 
1149 device_t
1150 config_found(device_t parent, void *aux, cfprint_t print)
1151 {
1152 
1153 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
1154 }
1155 
1156 /*
1157  * As above, but for root devices.
1158  */
1159 device_t
1160 config_rootfound(const char *rootname, void *aux)
1161 {
1162 	cfdata_t cf;
1163 
1164 	if ((cf = config_rootsearch(NULL, rootname, aux)) != NULL)
1165 		return config_attach(ROOT, cf, aux, NULL);
1166 	aprint_error("root device %s not configured\n", rootname);
1167 	return NULL;
1168 }
1169 
1170 /* just like sprintf(buf, "%d") except that it works from the end */
1171 static char *
1172 number(char *ep, int n)
1173 {
1174 
1175 	*--ep = 0;
1176 	while (n >= 10) {
1177 		*--ep = (n % 10) + '0';
1178 		n /= 10;
1179 	}
1180 	*--ep = n + '0';
1181 	return ep;
1182 }
1183 
1184 /*
1185  * Expand the size of the cd_devs array if necessary.
1186  *
1187  * The caller must hold alldevs_lock. config_makeroom() may release and
1188  * re-acquire alldevs_lock, so callers should re-check conditions such
1189  * as alldevs_nwrite == 0 and alldevs_nread == 0 when config_makeroom()
1190  * returns.
1191  */
1192 static void
1193 config_makeroom(int n, struct cfdriver *cd)
1194 {
1195 	int ondevs, nndevs;
1196 	device_t *osp, *nsp;
1197 
1198 	KASSERT(mutex_owned(&alldevs_lock));
1199 	alldevs_nwrite++;
1200 
1201 	for (nndevs = MAX(4, cd->cd_ndevs); nndevs <= n; nndevs += nndevs)
1202 		;
1203 
1204 	while (n >= cd->cd_ndevs) {
1205 		/*
1206 		 * Need to expand the array.
1207 		 */
1208 		ondevs = cd->cd_ndevs;
1209 		osp = cd->cd_devs;
1210 
1211 		/*
1212 		 * Release alldevs_lock around allocation, which may
1213 		 * sleep.
1214 		 */
1215 		mutex_exit(&alldevs_lock);
1216 		nsp = kmem_alloc(sizeof(device_t) * nndevs, KM_SLEEP);
1217 		mutex_enter(&alldevs_lock);
1218 
1219 		/*
1220 		 * If another thread moved the array while we did
1221 		 * not hold alldevs_lock, try again.
1222 		 */
1223 		if (cd->cd_devs != osp) {
1224 			mutex_exit(&alldevs_lock);
1225 			kmem_free(nsp, sizeof(device_t) * nndevs);
1226 			mutex_enter(&alldevs_lock);
1227 			continue;
1228 		}
1229 
1230 		memset(nsp + ondevs, 0, sizeof(device_t) * (nndevs - ondevs));
1231 		if (ondevs != 0)
1232 			memcpy(nsp, cd->cd_devs, sizeof(device_t) * ondevs);
1233 
1234 		cd->cd_ndevs = nndevs;
1235 		cd->cd_devs = nsp;
1236 		if (ondevs != 0) {
1237 			mutex_exit(&alldevs_lock);
1238 			kmem_free(osp, sizeof(device_t) * ondevs);
1239 			mutex_enter(&alldevs_lock);
1240 		}
1241 	}
1242 	KASSERT(mutex_owned(&alldevs_lock));
1243 	alldevs_nwrite--;
1244 }
1245 
1246 /*
1247  * Put dev into the devices list.
1248  */
1249 static void
1250 config_devlink(device_t dev)
1251 {
1252 
1253 	mutex_enter(&alldevs_lock);
1254 
1255 	KASSERT(device_cfdriver(dev)->cd_devs[dev->dv_unit] == dev);
1256 
1257 	dev->dv_add_gen = alldevs_gen;
1258 	/* It is safe to add a device to the tail of the list while
1259 	 * readers and writers are in the list.
1260 	 */
1261 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);
1262 	mutex_exit(&alldevs_lock);
1263 }
1264 
1265 static void
1266 config_devfree(device_t dev)
1267 {
1268 	KASSERT(dev->dv_flags & DVF_PRIV_ALLOC);
1269 
1270 	if (dev->dv_cfattach->ca_devsize > 0)
1271 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
1272 	kmem_free(dev, sizeof(*dev));
1273 }
1274 
1275 /*
1276  * Caller must hold alldevs_lock.
1277  */
1278 static void
1279 config_devunlink(device_t dev, struct devicelist *garbage)
1280 {
1281 	struct device_garbage *dg = &dev->dv_garbage;
1282 	cfdriver_t cd = device_cfdriver(dev);
1283 	int i;
1284 
1285 	KASSERT(mutex_owned(&alldevs_lock));
1286 
1287  	/* Unlink from device list.  Link to garbage list. */
1288 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1289 	TAILQ_INSERT_TAIL(garbage, dev, dv_list);
1290 
1291 	/* Remove from cfdriver's array. */
1292 	cd->cd_devs[dev->dv_unit] = NULL;
1293 
1294 	/*
1295 	 * If the device now has no units in use, unlink its softc array.
1296 	 */
1297 	for (i = 0; i < cd->cd_ndevs; i++) {
1298 		if (cd->cd_devs[i] != NULL)
1299 			break;
1300 	}
1301 	/* Nothing found.  Unlink, now.  Deallocate, later. */
1302 	if (i == cd->cd_ndevs) {
1303 		dg->dg_ndevs = cd->cd_ndevs;
1304 		dg->dg_devs = cd->cd_devs;
1305 		cd->cd_devs = NULL;
1306 		cd->cd_ndevs = 0;
1307 	}
1308 }
1309 
1310 static void
1311 config_devdelete(device_t dev)
1312 {
1313 	struct device_garbage *dg = &dev->dv_garbage;
1314 	device_lock_t dvl = device_getlock(dev);
1315 
1316 	if (dg->dg_devs != NULL)
1317 		kmem_free(dg->dg_devs, sizeof(device_t) * dg->dg_ndevs);
1318 
1319 	cv_destroy(&dvl->dvl_cv);
1320 	mutex_destroy(&dvl->dvl_mtx);
1321 
1322 	KASSERT(dev->dv_properties != NULL);
1323 	prop_object_release(dev->dv_properties);
1324 
1325 	if (dev->dv_activity_handlers)
1326 		panic("%s with registered handlers", __func__);
1327 
1328 	if (dev->dv_locators) {
1329 		size_t amount = *--dev->dv_locators;
1330 		kmem_free(dev->dv_locators, amount);
1331 	}
1332 
1333 	config_devfree(dev);
1334 }
1335 
1336 static int
1337 config_unit_nextfree(cfdriver_t cd, cfdata_t cf)
1338 {
1339 	int unit;
1340 
1341 	if (cf->cf_fstate == FSTATE_STAR) {
1342 		for (unit = cf->cf_unit; unit < cd->cd_ndevs; unit++)
1343 			if (cd->cd_devs[unit] == NULL)
1344 				break;
1345 		/*
1346 		 * unit is now the unit of the first NULL device pointer,
1347 		 * or max(cd->cd_ndevs,cf->cf_unit).
1348 		 */
1349 	} else {
1350 		unit = cf->cf_unit;
1351 		if (unit < cd->cd_ndevs && cd->cd_devs[unit] != NULL)
1352 			unit = -1;
1353 	}
1354 	return unit;
1355 }
1356 
1357 static int
1358 config_unit_alloc(device_t dev, cfdriver_t cd, cfdata_t cf)
1359 {
1360 	struct alldevs_foray af;
1361 	int unit;
1362 
1363 	config_alldevs_enter(&af);
1364 	for (;;) {
1365 		unit = config_unit_nextfree(cd, cf);
1366 		if (unit == -1)
1367 			break;
1368 		if (unit < cd->cd_ndevs) {
1369 			cd->cd_devs[unit] = dev;
1370 			dev->dv_unit = unit;
1371 			break;
1372 		}
1373 		config_makeroom(unit, cd);
1374 	}
1375 	config_alldevs_exit(&af);
1376 
1377 	return unit;
1378 }
1379 
1380 static device_t
1381 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1382 {
1383 	cfdriver_t cd;
1384 	cfattach_t ca;
1385 	size_t lname, lunit;
1386 	const char *xunit;
1387 	int myunit;
1388 	char num[10];
1389 	device_t dev;
1390 	void *dev_private;
1391 	const struct cfiattrdata *ia;
1392 	device_lock_t dvl;
1393 
1394 	cd = config_cfdriver_lookup(cf->cf_name);
1395 	if (cd == NULL)
1396 		return NULL;
1397 
1398 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1399 	if (ca == NULL)
1400 		return NULL;
1401 
1402 	/* get memory for all device vars */
1403 	KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1404 	if (ca->ca_devsize > 0) {
1405 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
1406 	} else {
1407 		dev_private = NULL;
1408 	}
1409 	dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
1410 
1411 	dev->dv_class = cd->cd_class;
1412 	dev->dv_cfdata = cf;
1413 	dev->dv_cfdriver = cd;
1414 	dev->dv_cfattach = ca;
1415 	dev->dv_activity_count = 0;
1416 	dev->dv_activity_handlers = NULL;
1417 	dev->dv_private = dev_private;
1418 	dev->dv_flags = ca->ca_flags;	/* inherit flags from class */
1419 
1420 	myunit = config_unit_alloc(dev, cd, cf);
1421 	if (myunit == -1) {
1422 		config_devfree(dev);
1423 		return NULL;
1424 	}
1425 
1426 	/* compute length of name and decimal expansion of unit number */
1427 	lname = strlen(cd->cd_name);
1428 	xunit = number(&num[sizeof(num)], myunit);
1429 	lunit = &num[sizeof(num)] - xunit;
1430 	if (lname + lunit > sizeof(dev->dv_xname))
1431 		panic("config_devalloc: device name too long");
1432 
1433 	dvl = device_getlock(dev);
1434 
1435 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
1436 	cv_init(&dvl->dvl_cv, "pmfsusp");
1437 
1438 	memcpy(dev->dv_xname, cd->cd_name, lname);
1439 	memcpy(dev->dv_xname + lname, xunit, lunit);
1440 	dev->dv_parent = parent;
1441 	if (parent != NULL)
1442 		dev->dv_depth = parent->dv_depth + 1;
1443 	else
1444 		dev->dv_depth = 0;
1445 	dev->dv_flags |= DVF_ACTIVE;	/* always initially active */
1446 	if (locs) {
1447 		KASSERT(parent); /* no locators at root */
1448 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
1449 		dev->dv_locators =
1450 		    kmem_alloc(sizeof(int) * (ia->ci_loclen + 1), KM_SLEEP);
1451 		*dev->dv_locators++ = sizeof(int) * (ia->ci_loclen + 1);
1452 		memcpy(dev->dv_locators, locs, sizeof(int) * ia->ci_loclen);
1453 	}
1454 	dev->dv_properties = prop_dictionary_create();
1455 	KASSERT(dev->dv_properties != NULL);
1456 
1457 	prop_dictionary_set_string_nocopy(dev->dv_properties,
1458 	    "device-driver", dev->dv_cfdriver->cd_name);
1459 	prop_dictionary_set_uint16(dev->dv_properties,
1460 	    "device-unit", dev->dv_unit);
1461 	if (parent != NULL) {
1462 		prop_dictionary_set_string(dev->dv_properties,
1463 		    "device-parent", device_xname(parent));
1464 	}
1465 
1466 	if (dev->dv_cfdriver->cd_attrs != NULL)
1467 		config_add_attrib_dict(dev);
1468 
1469 	return dev;
1470 }
1471 
1472 /*
1473  * Create an array of device attach attributes and add it
1474  * to the device's dv_properties dictionary.
1475  *
1476  * <key>interface-attributes</key>
1477  * <array>
1478  *    <dict>
1479  *       <key>attribute-name</key>
1480  *       <string>foo</string>
1481  *       <key>locators</key>
1482  *       <array>
1483  *          <dict>
1484  *             <key>loc-name</key>
1485  *             <string>foo-loc1</string>
1486  *          </dict>
1487  *          <dict>
1488  *             <key>loc-name</key>
1489  *             <string>foo-loc2</string>
1490  *             <key>default</key>
1491  *             <string>foo-loc2-default</string>
1492  *          </dict>
1493  *          ...
1494  *       </array>
1495  *    </dict>
1496  *    ...
1497  * </array>
1498  */
1499 
1500 static void
1501 config_add_attrib_dict(device_t dev)
1502 {
1503 	int i, j;
1504 	const struct cfiattrdata *ci;
1505 	prop_dictionary_t attr_dict, loc_dict;
1506 	prop_array_t attr_array, loc_array;
1507 
1508 	if ((attr_array = prop_array_create()) == NULL)
1509 		return;
1510 
1511 	for (i = 0; ; i++) {
1512 		if ((ci = dev->dv_cfdriver->cd_attrs[i]) == NULL)
1513 			break;
1514 		if ((attr_dict = prop_dictionary_create()) == NULL)
1515 			break;
1516 		prop_dictionary_set_string_nocopy(attr_dict, "attribute-name",
1517 		    ci->ci_name);
1518 
1519 		/* Create an array of the locator names and defaults */
1520 
1521 		if (ci->ci_loclen != 0 &&
1522 		    (loc_array = prop_array_create()) != NULL) {
1523 			for (j = 0; j < ci->ci_loclen; j++) {
1524 				loc_dict = prop_dictionary_create();
1525 				if (loc_dict == NULL)
1526 					continue;
1527 				prop_dictionary_set_string_nocopy(loc_dict,
1528 				    "loc-name", ci->ci_locdesc[j].cld_name);
1529 				if (ci->ci_locdesc[j].cld_defaultstr != NULL)
1530 					prop_dictionary_set_string_nocopy(
1531 					    loc_dict, "default",
1532 					    ci->ci_locdesc[j].cld_defaultstr);
1533 				prop_array_set(loc_array, j, loc_dict);
1534 				prop_object_release(loc_dict);
1535 			}
1536 			prop_dictionary_set_and_rel(attr_dict, "locators",
1537 			    loc_array);
1538 		}
1539 		prop_array_add(attr_array, attr_dict);
1540 		prop_object_release(attr_dict);
1541 	}
1542 	if (i == 0)
1543 		prop_object_release(attr_array);
1544 	else
1545 		prop_dictionary_set_and_rel(dev->dv_properties,
1546 		    "interface-attributes", attr_array);
1547 
1548 	return;
1549 }
1550 
1551 /*
1552  * Attach a found device.
1553  */
1554 device_t
1555 config_attach_loc(device_t parent, cfdata_t cf,
1556 	const int *locs, void *aux, cfprint_t print)
1557 {
1558 	device_t dev;
1559 	struct cftable *ct;
1560 	const char *drvname;
1561 
1562 	dev = config_devalloc(parent, cf, locs);
1563 	if (!dev)
1564 		panic("config_attach: allocation of device softc failed");
1565 
1566 	/* XXX redundant - see below? */
1567 	if (cf->cf_fstate != FSTATE_STAR) {
1568 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1569 		cf->cf_fstate = FSTATE_FOUND;
1570 	}
1571 
1572 	config_devlink(dev);
1573 
1574 	if (config_do_twiddle && cold)
1575 		twiddle();
1576 	else
1577 		aprint_naive("Found ");
1578 	/*
1579 	 * We want the next two printfs for normal, verbose, and quiet,
1580 	 * but not silent (in which case, we're twiddling, instead).
1581 	 */
1582 	if (parent == ROOT) {
1583 		aprint_naive("%s (root)", device_xname(dev));
1584 		aprint_normal("%s (root)", device_xname(dev));
1585 	} else {
1586 		aprint_naive("%s at %s", device_xname(dev),
1587 		    device_xname(parent));
1588 		aprint_normal("%s at %s", device_xname(dev),
1589 		    device_xname(parent));
1590 		if (print)
1591 			(void) (*print)(aux, NULL);
1592 	}
1593 
1594 	/*
1595 	 * Before attaching, clobber any unfound devices that are
1596 	 * otherwise identical.
1597 	 * XXX code above is redundant?
1598 	 */
1599 	drvname = dev->dv_cfdriver->cd_name;
1600 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1601 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1602 			if (STREQ(cf->cf_name, drvname) &&
1603 			    cf->cf_unit == dev->dv_unit) {
1604 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1605 					cf->cf_fstate = FSTATE_FOUND;
1606 			}
1607 		}
1608 	}
1609 	device_register(dev, aux);
1610 
1611 	/* Let userland know */
1612 	devmon_report_device(dev, true);
1613 
1614 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1615 
1616 	if (((dev->dv_flags & DVF_ATTACH_INPROGRESS) == 0)
1617 	    && !device_pmf_is_registered(dev))
1618 		aprint_debug_dev(dev,
1619 		    "WARNING: power management not supported\n");
1620 
1621 	config_process_deferred(&deferred_config_queue, dev);
1622 
1623 	device_register_post_config(dev, aux);
1624 	return dev;
1625 }
1626 
1627 device_t
1628 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1629 {
1630 
1631 	return config_attach_loc(parent, cf, NULL, aux, print);
1632 }
1633 
1634 /*
1635  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1636  * way are silently inserted into the device tree, and their children
1637  * attached.
1638  *
1639  * Note that because pseudo-devices are attached silently, any information
1640  * the attach routine wishes to print should be prefixed with the device
1641  * name by the attach routine.
1642  */
1643 device_t
1644 config_attach_pseudo(cfdata_t cf)
1645 {
1646 	device_t dev;
1647 
1648 	dev = config_devalloc(ROOT, cf, NULL);
1649 	if (!dev)
1650 		return NULL;
1651 
1652 	/* XXX mark busy in cfdata */
1653 
1654 	if (cf->cf_fstate != FSTATE_STAR) {
1655 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1656 		cf->cf_fstate = FSTATE_FOUND;
1657 	}
1658 
1659 	config_devlink(dev);
1660 
1661 #if 0	/* XXXJRT not yet */
1662 	device_register(dev, NULL);	/* like a root node */
1663 #endif
1664 
1665 	/* Let userland know */
1666 	devmon_report_device(dev, true);
1667 
1668 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1669 
1670 	config_process_deferred(&deferred_config_queue, dev);
1671 	return dev;
1672 }
1673 
1674 /*
1675  * Caller must hold alldevs_lock.
1676  */
1677 static void
1678 config_collect_garbage(struct devicelist *garbage)
1679 {
1680 	device_t dv;
1681 
1682 	KASSERT(!cpu_intr_p());
1683 	KASSERT(!cpu_softintr_p());
1684 	KASSERT(mutex_owned(&alldevs_lock));
1685 
1686 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
1687 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
1688 			if (dv->dv_del_gen != 0)
1689 				break;
1690 		}
1691 		if (dv == NULL) {
1692 			alldevs_garbage = false;
1693 			break;
1694 		}
1695 		config_devunlink(dv, garbage);
1696 	}
1697 	KASSERT(mutex_owned(&alldevs_lock));
1698 }
1699 
1700 static void
1701 config_dump_garbage(struct devicelist *garbage)
1702 {
1703 	device_t dv;
1704 
1705 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
1706 		TAILQ_REMOVE(garbage, dv, dv_list);
1707 		config_devdelete(dv);
1708 	}
1709 }
1710 
1711 /*
1712  * Detach a device.  Optionally forced (e.g. because of hardware
1713  * removal) and quiet.  Returns zero if successful, non-zero
1714  * (an error code) otherwise.
1715  *
1716  * Note that this code wants to be run from a process context, so
1717  * that the detach can sleep to allow processes which have a device
1718  * open to run and unwind their stacks.
1719  */
1720 int
1721 config_detach(device_t dev, int flags)
1722 {
1723 	struct alldevs_foray af;
1724 	struct cftable *ct;
1725 	cfdata_t cf;
1726 	const struct cfattach *ca;
1727 	struct cfdriver *cd;
1728 	device_t d __diagused;
1729 	int rv = 0;
1730 
1731 	cf = dev->dv_cfdata;
1732 	KASSERTMSG((cf == NULL || cf->cf_fstate == FSTATE_FOUND ||
1733 		cf->cf_fstate == FSTATE_STAR),
1734 	    "config_detach: %s: bad device fstate: %d",
1735 	    device_xname(dev), cf ? cf->cf_fstate : -1);
1736 
1737 	cd = dev->dv_cfdriver;
1738 	KASSERT(cd != NULL);
1739 
1740 	ca = dev->dv_cfattach;
1741 	KASSERT(ca != NULL);
1742 
1743 	mutex_enter(&alldevs_lock);
1744 	if (dev->dv_del_gen != 0) {
1745 		mutex_exit(&alldevs_lock);
1746 #ifdef DIAGNOSTIC
1747 		printf("%s: %s is already detached\n", __func__,
1748 		    device_xname(dev));
1749 #endif /* DIAGNOSTIC */
1750 		return ENOENT;
1751 	}
1752 	alldevs_nwrite++;
1753 	mutex_exit(&alldevs_lock);
1754 
1755 	if (!detachall &&
1756 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
1757 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
1758 		rv = EOPNOTSUPP;
1759 	} else if (ca->ca_detach != NULL) {
1760 		rv = (*ca->ca_detach)(dev, flags);
1761 	} else
1762 		rv = EOPNOTSUPP;
1763 
1764 	/*
1765 	 * If it was not possible to detach the device, then we either
1766 	 * panic() (for the forced but failed case), or return an error.
1767 	 *
1768 	 * If it was possible to detach the device, ensure that the
1769 	 * device is deactivated.
1770 	 */
1771 	if (rv == 0)
1772 		dev->dv_flags &= ~DVF_ACTIVE;
1773 	else if ((flags & DETACH_FORCE) == 0)
1774 		goto out;
1775 	else {
1776 		panic("config_detach: forced detach of %s failed (%d)",
1777 		    device_xname(dev), rv);
1778 	}
1779 
1780 	/*
1781 	 * The device has now been successfully detached.
1782 	 */
1783 
1784 	/* Let userland know */
1785 	devmon_report_device(dev, false);
1786 
1787 #ifdef DIAGNOSTIC
1788 	/*
1789 	 * Sanity: If you're successfully detached, you should have no
1790 	 * children.  (Note that because children must be attached
1791 	 * after parents, we only need to search the latter part of
1792 	 * the list.)
1793 	 */
1794 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1795 	    d = TAILQ_NEXT(d, dv_list)) {
1796 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
1797 			printf("config_detach: detached device %s"
1798 			    " has children %s\n", device_xname(dev),
1799 			    device_xname(d));
1800 			panic("config_detach");
1801 		}
1802 	}
1803 #endif
1804 
1805 	/* notify the parent that the child is gone */
1806 	if (dev->dv_parent) {
1807 		device_t p = dev->dv_parent;
1808 		if (p->dv_cfattach->ca_childdetached)
1809 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1810 	}
1811 
1812 	/*
1813 	 * Mark cfdata to show that the unit can be reused, if possible.
1814 	 */
1815 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1816 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1817 			if (STREQ(cf->cf_name, cd->cd_name)) {
1818 				if (cf->cf_fstate == FSTATE_FOUND &&
1819 				    cf->cf_unit == dev->dv_unit)
1820 					cf->cf_fstate = FSTATE_NOTFOUND;
1821 			}
1822 		}
1823 	}
1824 
1825 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1826 		aprint_normal_dev(dev, "detached\n");
1827 
1828 out:
1829 	config_alldevs_enter(&af);
1830 	KASSERT(alldevs_nwrite != 0);
1831 	--alldevs_nwrite;
1832 	if (rv == 0 && dev->dv_del_gen == 0) {
1833 		if (alldevs_nwrite == 0 && alldevs_nread == 0)
1834 			config_devunlink(dev, &af.af_garbage);
1835 		else {
1836 			dev->dv_del_gen = alldevs_gen;
1837 			alldevs_garbage = true;
1838 		}
1839 	}
1840 	config_alldevs_exit(&af);
1841 
1842 	return rv;
1843 }
1844 
1845 int
1846 config_detach_children(device_t parent, int flags)
1847 {
1848 	device_t dv;
1849 	deviter_t di;
1850 	int error = 0;
1851 
1852 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1853 	     dv = deviter_next(&di)) {
1854 		if (device_parent(dv) != parent)
1855 			continue;
1856 		if ((error = config_detach(dv, flags)) != 0)
1857 			break;
1858 	}
1859 	deviter_release(&di);
1860 	return error;
1861 }
1862 
1863 device_t
1864 shutdown_first(struct shutdown_state *s)
1865 {
1866 	if (!s->initialized) {
1867 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
1868 		s->initialized = true;
1869 	}
1870 	return shutdown_next(s);
1871 }
1872 
1873 device_t
1874 shutdown_next(struct shutdown_state *s)
1875 {
1876 	device_t dv;
1877 
1878 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
1879 		;
1880 
1881 	if (dv == NULL)
1882 		s->initialized = false;
1883 
1884 	return dv;
1885 }
1886 
1887 bool
1888 config_detach_all(int how)
1889 {
1890 	static struct shutdown_state s;
1891 	device_t curdev;
1892 	bool progress = false;
1893 	int flags;
1894 
1895 	if ((how & (RB_NOSYNC|RB_DUMP)) != 0)
1896 		return false;
1897 
1898 	if ((how & RB_POWERDOWN) == RB_POWERDOWN)
1899 		flags = DETACH_SHUTDOWN | DETACH_POWEROFF;
1900 	else
1901 		flags = DETACH_SHUTDOWN;
1902 
1903 	for (curdev = shutdown_first(&s); curdev != NULL;
1904 	     curdev = shutdown_next(&s)) {
1905 		aprint_debug(" detaching %s, ", device_xname(curdev));
1906 		if (config_detach(curdev, flags) == 0) {
1907 			progress = true;
1908 			aprint_debug("success.");
1909 		} else
1910 			aprint_debug("failed.");
1911 	}
1912 	return progress;
1913 }
1914 
1915 static bool
1916 device_is_ancestor_of(device_t ancestor, device_t descendant)
1917 {
1918 	device_t dv;
1919 
1920 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
1921 		if (device_parent(dv) == ancestor)
1922 			return true;
1923 	}
1924 	return false;
1925 }
1926 
1927 int
1928 config_deactivate(device_t dev)
1929 {
1930 	deviter_t di;
1931 	const struct cfattach *ca;
1932 	device_t descendant;
1933 	int s, rv = 0, oflags;
1934 
1935 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
1936 	     descendant != NULL;
1937 	     descendant = deviter_next(&di)) {
1938 		if (dev != descendant &&
1939 		    !device_is_ancestor_of(dev, descendant))
1940 			continue;
1941 
1942 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
1943 			continue;
1944 
1945 		ca = descendant->dv_cfattach;
1946 		oflags = descendant->dv_flags;
1947 
1948 		descendant->dv_flags &= ~DVF_ACTIVE;
1949 		if (ca->ca_activate == NULL)
1950 			continue;
1951 		s = splhigh();
1952 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
1953 		splx(s);
1954 		if (rv != 0)
1955 			descendant->dv_flags = oflags;
1956 	}
1957 	deviter_release(&di);
1958 	return rv;
1959 }
1960 
1961 /*
1962  * Defer the configuration of the specified device until all
1963  * of its parent's devices have been attached.
1964  */
1965 void
1966 config_defer(device_t dev, void (*func)(device_t))
1967 {
1968 	struct deferred_config *dc;
1969 
1970 	if (dev->dv_parent == NULL)
1971 		panic("config_defer: can't defer config of a root device");
1972 
1973 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1974 
1975 	config_pending_incr(dev);
1976 
1977 	mutex_enter(&config_misc_lock);
1978 #ifdef DIAGNOSTIC
1979 	struct deferred_config *odc;
1980 	TAILQ_FOREACH(odc, &deferred_config_queue, dc_queue) {
1981 		if (odc->dc_dev == dev)
1982 			panic("config_defer: deferred twice");
1983 	}
1984 #endif
1985 	dc->dc_dev = dev;
1986 	dc->dc_func = func;
1987 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1988 	mutex_exit(&config_misc_lock);
1989 }
1990 
1991 /*
1992  * Defer some autoconfiguration for a device until after interrupts
1993  * are enabled.
1994  */
1995 void
1996 config_interrupts(device_t dev, void (*func)(device_t))
1997 {
1998 	struct deferred_config *dc;
1999 
2000 	/*
2001 	 * If interrupts are enabled, callback now.
2002 	 */
2003 	if (cold == 0) {
2004 		(*func)(dev);
2005 		return;
2006 	}
2007 
2008 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
2009 
2010 	config_pending_incr(dev);
2011 
2012 	mutex_enter(&config_misc_lock);
2013 #ifdef DIAGNOSTIC
2014 	struct deferred_config *odc;
2015 	TAILQ_FOREACH(odc, &interrupt_config_queue, dc_queue) {
2016 		if (odc->dc_dev == dev)
2017 			panic("config_interrupts: deferred twice");
2018 	}
2019 #endif
2020 	dc->dc_dev = dev;
2021 	dc->dc_func = func;
2022 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
2023 	dev->dv_flags |= DVF_ATTACH_INPROGRESS;
2024 	mutex_exit(&config_misc_lock);
2025 }
2026 
2027 /*
2028  * Defer some autoconfiguration for a device until after root file system
2029  * is mounted (to load firmware etc).
2030  */
2031 void
2032 config_mountroot(device_t dev, void (*func)(device_t))
2033 {
2034 	struct deferred_config *dc;
2035 
2036 	/*
2037 	 * If root file system is mounted, callback now.
2038 	 */
2039 	if (root_is_mounted) {
2040 		(*func)(dev);
2041 		return;
2042 	}
2043 
2044 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
2045 
2046 	mutex_enter(&config_misc_lock);
2047 #ifdef DIAGNOSTIC
2048 	struct deferred_config *odc;
2049 	TAILQ_FOREACH(odc, &mountroot_config_queue, dc_queue) {
2050 		if (odc->dc_dev == dev)
2051 			panic("%s: deferred twice", __func__);
2052 	}
2053 #endif
2054 
2055 	dc->dc_dev = dev;
2056 	dc->dc_func = func;
2057 	TAILQ_INSERT_TAIL(&mountroot_config_queue, dc, dc_queue);
2058 	mutex_exit(&config_misc_lock);
2059 }
2060 
2061 /*
2062  * Process a deferred configuration queue.
2063  */
2064 static void
2065 config_process_deferred(struct deferred_config_head *queue, device_t parent)
2066 {
2067 	struct deferred_config *dc;
2068 
2069 	mutex_enter(&config_misc_lock);
2070 	dc = TAILQ_FIRST(queue);
2071 	while (dc) {
2072 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
2073 			TAILQ_REMOVE(queue, dc, dc_queue);
2074 			mutex_exit(&config_misc_lock);
2075 
2076 			(*dc->dc_func)(dc->dc_dev);
2077 			config_pending_decr(dc->dc_dev);
2078 			kmem_free(dc, sizeof(*dc));
2079 
2080 			mutex_enter(&config_misc_lock);
2081 			/* Restart, queue might have changed */
2082 			dc = TAILQ_FIRST(queue);
2083 		} else {
2084 			dc = TAILQ_NEXT(dc, dc_queue);
2085 		}
2086 	}
2087 	mutex_exit(&config_misc_lock);
2088 }
2089 
2090 /*
2091  * Manipulate the config_pending semaphore.
2092  */
2093 void
2094 config_pending_incr(device_t dev)
2095 {
2096 
2097 	mutex_enter(&config_misc_lock);
2098 	config_pending++;
2099 #ifdef DEBUG_AUTOCONF
2100 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
2101 #endif
2102 	mutex_exit(&config_misc_lock);
2103 }
2104 
2105 void
2106 config_pending_decr(device_t dev)
2107 {
2108 
2109 	KASSERT(0 < config_pending);
2110 	mutex_enter(&config_misc_lock);
2111 	config_pending--;
2112 #ifdef DEBUG_AUTOCONF
2113 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
2114 #endif
2115 	if (config_pending == 0)
2116 		cv_broadcast(&config_misc_cv);
2117 	mutex_exit(&config_misc_lock);
2118 }
2119 
2120 /*
2121  * Register a "finalization" routine.  Finalization routines are
2122  * called iteratively once all real devices have been found during
2123  * autoconfiguration, for as long as any one finalizer has done
2124  * any work.
2125  */
2126 int
2127 config_finalize_register(device_t dev, int (*fn)(device_t))
2128 {
2129 	struct finalize_hook *f;
2130 
2131 	/*
2132 	 * If finalization has already been done, invoke the
2133 	 * callback function now.
2134 	 */
2135 	if (config_finalize_done) {
2136 		while ((*fn)(dev) != 0)
2137 			/* loop */ ;
2138 		return 0;
2139 	}
2140 
2141 	/* Ensure this isn't already on the list. */
2142 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
2143 		if (f->f_func == fn && f->f_dev == dev)
2144 			return EEXIST;
2145 	}
2146 
2147 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
2148 	f->f_func = fn;
2149 	f->f_dev = dev;
2150 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
2151 
2152 	return 0;
2153 }
2154 
2155 void
2156 config_finalize(void)
2157 {
2158 	struct finalize_hook *f;
2159 	struct pdevinit *pdev;
2160 	extern struct pdevinit pdevinit[];
2161 	int errcnt, rv;
2162 
2163 	/*
2164 	 * Now that device driver threads have been created, wait for
2165 	 * them to finish any deferred autoconfiguration.
2166 	 */
2167 	mutex_enter(&config_misc_lock);
2168 	while (config_pending != 0)
2169 		cv_wait(&config_misc_cv, &config_misc_lock);
2170 	mutex_exit(&config_misc_lock);
2171 
2172 	KERNEL_LOCK(1, NULL);
2173 
2174 	/* Attach pseudo-devices. */
2175 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
2176 		(*pdev->pdev_attach)(pdev->pdev_count);
2177 
2178 	/* Run the hooks until none of them does any work. */
2179 	do {
2180 		rv = 0;
2181 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
2182 			rv |= (*f->f_func)(f->f_dev);
2183 	} while (rv != 0);
2184 
2185 	config_finalize_done = 1;
2186 
2187 	/* Now free all the hooks. */
2188 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
2189 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
2190 		kmem_free(f, sizeof(*f));
2191 	}
2192 
2193 	KERNEL_UNLOCK_ONE(NULL);
2194 
2195 	errcnt = aprint_get_error_count();
2196 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
2197 	    (boothowto & AB_VERBOSE) == 0) {
2198 		mutex_enter(&config_misc_lock);
2199 		if (config_do_twiddle) {
2200 			config_do_twiddle = 0;
2201 			printf_nolog(" done.\n");
2202 		}
2203 		mutex_exit(&config_misc_lock);
2204 	}
2205 	if (errcnt != 0) {
2206 		printf("WARNING: %d error%s while detecting hardware; "
2207 		    "check system log.\n", errcnt,
2208 		    errcnt == 1 ? "" : "s");
2209 	}
2210 }
2211 
2212 void
2213 config_twiddle_init(void)
2214 {
2215 
2216 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
2217 		config_do_twiddle = 1;
2218 	}
2219 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
2220 }
2221 
2222 void
2223 config_twiddle_fn(void *cookie)
2224 {
2225 
2226 	mutex_enter(&config_misc_lock);
2227 	if (config_do_twiddle) {
2228 		twiddle();
2229 		callout_schedule(&config_twiddle_ch, mstohz(100));
2230 	}
2231 	mutex_exit(&config_misc_lock);
2232 }
2233 
2234 static void
2235 config_alldevs_enter(struct alldevs_foray *af)
2236 {
2237 	TAILQ_INIT(&af->af_garbage);
2238 	mutex_enter(&alldevs_lock);
2239 	config_collect_garbage(&af->af_garbage);
2240 }
2241 
2242 static void
2243 config_alldevs_exit(struct alldevs_foray *af)
2244 {
2245 	mutex_exit(&alldevs_lock);
2246 	config_dump_garbage(&af->af_garbage);
2247 }
2248 
2249 /*
2250  * device_lookup:
2251  *
2252  *	Look up a device instance for a given driver.
2253  */
2254 device_t
2255 device_lookup(cfdriver_t cd, int unit)
2256 {
2257 	device_t dv;
2258 
2259 	mutex_enter(&alldevs_lock);
2260 	if (unit < 0 || unit >= cd->cd_ndevs)
2261 		dv = NULL;
2262 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
2263 		dv = NULL;
2264 	mutex_exit(&alldevs_lock);
2265 
2266 	return dv;
2267 }
2268 
2269 /*
2270  * device_lookup_private:
2271  *
2272  *	Look up a softc instance for a given driver.
2273  */
2274 void *
2275 device_lookup_private(cfdriver_t cd, int unit)
2276 {
2277 
2278 	return device_private(device_lookup(cd, unit));
2279 }
2280 
2281 /*
2282  * device_find_by_xname:
2283  *
2284  *	Returns the device of the given name or NULL if it doesn't exist.
2285  */
2286 device_t
2287 device_find_by_xname(const char *name)
2288 {
2289 	device_t dv;
2290 	deviter_t di;
2291 
2292 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
2293 		if (strcmp(device_xname(dv), name) == 0)
2294 			break;
2295 	}
2296 	deviter_release(&di);
2297 
2298 	return dv;
2299 }
2300 
2301 /*
2302  * device_find_by_driver_unit:
2303  *
2304  *	Returns the device of the given driver name and unit or
2305  *	NULL if it doesn't exist.
2306  */
2307 device_t
2308 device_find_by_driver_unit(const char *name, int unit)
2309 {
2310 	struct cfdriver *cd;
2311 
2312 	if ((cd = config_cfdriver_lookup(name)) == NULL)
2313 		return NULL;
2314 	return device_lookup(cd, unit);
2315 }
2316 
2317 /*
2318  * device_compatible_match:
2319  *
2320  *	Match a driver's "compatible" data against a device's
2321  *	"compatible" strings.  If a match is found, we return
2322  *	a weighted match result, and optionally the matching
2323  *	entry.
2324  */
2325 int
2326 device_compatible_match(const char **device_compats, int ndevice_compats,
2327 			const struct device_compatible_entry *driver_compats,
2328 			const struct device_compatible_entry **matching_entryp)
2329 {
2330 	const struct device_compatible_entry *dce = NULL;
2331 	int i, match_weight;
2332 
2333 	if (ndevice_compats == 0 || device_compats == NULL ||
2334 	    driver_compats == NULL)
2335 		return 0;
2336 
2337 	/*
2338 	 * We take the first match because we start with the most-specific
2339 	 * device compatible string.
2340 	 */
2341 	for (i = 0, match_weight = ndevice_compats - 1;
2342 	     i < ndevice_compats;
2343 	     i++, match_weight--) {
2344 		for (dce = driver_compats; dce->compat != NULL; dce++) {
2345 			if (strcmp(dce->compat, device_compats[i]) == 0) {
2346 				KASSERT(match_weight >= 0);
2347 				if (matching_entryp)
2348 					*matching_entryp = dce;
2349 				return 1 + match_weight;
2350 			}
2351 		}
2352 	}
2353 	return 0;
2354 }
2355 
2356 /*
2357  * Power management related functions.
2358  */
2359 
2360 bool
2361 device_pmf_is_registered(device_t dev)
2362 {
2363 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
2364 }
2365 
2366 bool
2367 device_pmf_driver_suspend(device_t dev, const pmf_qual_t *qual)
2368 {
2369 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2370 		return true;
2371 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2372 		return false;
2373 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2374 	    dev->dv_driver_suspend != NULL &&
2375 	    !(*dev->dv_driver_suspend)(dev, qual))
2376 		return false;
2377 
2378 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
2379 	return true;
2380 }
2381 
2382 bool
2383 device_pmf_driver_resume(device_t dev, const pmf_qual_t *qual)
2384 {
2385 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2386 		return true;
2387 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2388 		return false;
2389 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2390 	    dev->dv_driver_resume != NULL &&
2391 	    !(*dev->dv_driver_resume)(dev, qual))
2392 		return false;
2393 
2394 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2395 	return true;
2396 }
2397 
2398 bool
2399 device_pmf_driver_shutdown(device_t dev, int how)
2400 {
2401 
2402 	if (*dev->dv_driver_shutdown != NULL &&
2403 	    !(*dev->dv_driver_shutdown)(dev, how))
2404 		return false;
2405 	return true;
2406 }
2407 
2408 bool
2409 device_pmf_driver_register(device_t dev,
2410     bool (*suspend)(device_t, const pmf_qual_t *),
2411     bool (*resume)(device_t, const pmf_qual_t *),
2412     bool (*shutdown)(device_t, int))
2413 {
2414 	dev->dv_driver_suspend = suspend;
2415 	dev->dv_driver_resume = resume;
2416 	dev->dv_driver_shutdown = shutdown;
2417 	dev->dv_flags |= DVF_POWER_HANDLERS;
2418 	return true;
2419 }
2420 
2421 static const char *
2422 curlwp_name(void)
2423 {
2424 	if (curlwp->l_name != NULL)
2425 		return curlwp->l_name;
2426 	else
2427 		return curlwp->l_proc->p_comm;
2428 }
2429 
2430 void
2431 device_pmf_driver_deregister(device_t dev)
2432 {
2433 	device_lock_t dvl = device_getlock(dev);
2434 
2435 	dev->dv_driver_suspend = NULL;
2436 	dev->dv_driver_resume = NULL;
2437 
2438 	mutex_enter(&dvl->dvl_mtx);
2439 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2440 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
2441 		/* Wake a thread that waits for the lock.  That
2442 		 * thread will fail to acquire the lock, and then
2443 		 * it will wake the next thread that waits for the
2444 		 * lock, or else it will wake us.
2445 		 */
2446 		cv_signal(&dvl->dvl_cv);
2447 		pmflock_debug(dev, __func__, __LINE__);
2448 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2449 		pmflock_debug(dev, __func__, __LINE__);
2450 	}
2451 	mutex_exit(&dvl->dvl_mtx);
2452 }
2453 
2454 bool
2455 device_pmf_driver_child_register(device_t dev)
2456 {
2457 	device_t parent = device_parent(dev);
2458 
2459 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2460 		return true;
2461 	return (*parent->dv_driver_child_register)(dev);
2462 }
2463 
2464 void
2465 device_pmf_driver_set_child_register(device_t dev,
2466     bool (*child_register)(device_t))
2467 {
2468 	dev->dv_driver_child_register = child_register;
2469 }
2470 
2471 static void
2472 pmflock_debug(device_t dev, const char *func, int line)
2473 {
2474 	device_lock_t dvl = device_getlock(dev);
2475 
2476 	aprint_debug_dev(dev,
2477 	    "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n", func, line,
2478 	    curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait, dev->dv_flags);
2479 }
2480 
2481 static bool
2482 device_pmf_lock1(device_t dev)
2483 {
2484 	device_lock_t dvl = device_getlock(dev);
2485 
2486 	while (device_pmf_is_registered(dev) &&
2487 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
2488 		dvl->dvl_nwait++;
2489 		pmflock_debug(dev, __func__, __LINE__);
2490 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2491 		pmflock_debug(dev, __func__, __LINE__);
2492 		dvl->dvl_nwait--;
2493 	}
2494 	if (!device_pmf_is_registered(dev)) {
2495 		pmflock_debug(dev, __func__, __LINE__);
2496 		/* We could not acquire the lock, but some other thread may
2497 		 * wait for it, also.  Wake that thread.
2498 		 */
2499 		cv_signal(&dvl->dvl_cv);
2500 		return false;
2501 	}
2502 	dvl->dvl_nlock++;
2503 	dvl->dvl_holder = curlwp;
2504 	pmflock_debug(dev, __func__, __LINE__);
2505 	return true;
2506 }
2507 
2508 bool
2509 device_pmf_lock(device_t dev)
2510 {
2511 	bool rc;
2512 	device_lock_t dvl = device_getlock(dev);
2513 
2514 	mutex_enter(&dvl->dvl_mtx);
2515 	rc = device_pmf_lock1(dev);
2516 	mutex_exit(&dvl->dvl_mtx);
2517 
2518 	return rc;
2519 }
2520 
2521 void
2522 device_pmf_unlock(device_t dev)
2523 {
2524 	device_lock_t dvl = device_getlock(dev);
2525 
2526 	KASSERT(dvl->dvl_nlock > 0);
2527 	mutex_enter(&dvl->dvl_mtx);
2528 	if (--dvl->dvl_nlock == 0)
2529 		dvl->dvl_holder = NULL;
2530 	cv_signal(&dvl->dvl_cv);
2531 	pmflock_debug(dev, __func__, __LINE__);
2532 	mutex_exit(&dvl->dvl_mtx);
2533 }
2534 
2535 device_lock_t
2536 device_getlock(device_t dev)
2537 {
2538 	return &dev->dv_lock;
2539 }
2540 
2541 void *
2542 device_pmf_bus_private(device_t dev)
2543 {
2544 	return dev->dv_bus_private;
2545 }
2546 
2547 bool
2548 device_pmf_bus_suspend(device_t dev, const pmf_qual_t *qual)
2549 {
2550 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2551 		return true;
2552 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2553 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2554 		return false;
2555 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2556 	    dev->dv_bus_suspend != NULL &&
2557 	    !(*dev->dv_bus_suspend)(dev, qual))
2558 		return false;
2559 
2560 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2561 	return true;
2562 }
2563 
2564 bool
2565 device_pmf_bus_resume(device_t dev, const pmf_qual_t *qual)
2566 {
2567 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2568 		return true;
2569 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2570 	    dev->dv_bus_resume != NULL &&
2571 	    !(*dev->dv_bus_resume)(dev, qual))
2572 		return false;
2573 
2574 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2575 	return true;
2576 }
2577 
2578 bool
2579 device_pmf_bus_shutdown(device_t dev, int how)
2580 {
2581 
2582 	if (*dev->dv_bus_shutdown != NULL &&
2583 	    !(*dev->dv_bus_shutdown)(dev, how))
2584 		return false;
2585 	return true;
2586 }
2587 
2588 void
2589 device_pmf_bus_register(device_t dev, void *priv,
2590     bool (*suspend)(device_t, const pmf_qual_t *),
2591     bool (*resume)(device_t, const pmf_qual_t *),
2592     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2593 {
2594 	dev->dv_bus_private = priv;
2595 	dev->dv_bus_resume = resume;
2596 	dev->dv_bus_suspend = suspend;
2597 	dev->dv_bus_shutdown = shutdown;
2598 	dev->dv_bus_deregister = deregister;
2599 }
2600 
2601 void
2602 device_pmf_bus_deregister(device_t dev)
2603 {
2604 	if (dev->dv_bus_deregister == NULL)
2605 		return;
2606 	(*dev->dv_bus_deregister)(dev);
2607 	dev->dv_bus_private = NULL;
2608 	dev->dv_bus_suspend = NULL;
2609 	dev->dv_bus_resume = NULL;
2610 	dev->dv_bus_deregister = NULL;
2611 }
2612 
2613 void *
2614 device_pmf_class_private(device_t dev)
2615 {
2616 	return dev->dv_class_private;
2617 }
2618 
2619 bool
2620 device_pmf_class_suspend(device_t dev, const pmf_qual_t *qual)
2621 {
2622 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2623 		return true;
2624 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2625 	    dev->dv_class_suspend != NULL &&
2626 	    !(*dev->dv_class_suspend)(dev, qual))
2627 		return false;
2628 
2629 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2630 	return true;
2631 }
2632 
2633 bool
2634 device_pmf_class_resume(device_t dev, const pmf_qual_t *qual)
2635 {
2636 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2637 		return true;
2638 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2639 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2640 		return false;
2641 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2642 	    dev->dv_class_resume != NULL &&
2643 	    !(*dev->dv_class_resume)(dev, qual))
2644 		return false;
2645 
2646 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2647 	return true;
2648 }
2649 
2650 void
2651 device_pmf_class_register(device_t dev, void *priv,
2652     bool (*suspend)(device_t, const pmf_qual_t *),
2653     bool (*resume)(device_t, const pmf_qual_t *),
2654     void (*deregister)(device_t))
2655 {
2656 	dev->dv_class_private = priv;
2657 	dev->dv_class_suspend = suspend;
2658 	dev->dv_class_resume = resume;
2659 	dev->dv_class_deregister = deregister;
2660 }
2661 
2662 void
2663 device_pmf_class_deregister(device_t dev)
2664 {
2665 	if (dev->dv_class_deregister == NULL)
2666 		return;
2667 	(*dev->dv_class_deregister)(dev);
2668 	dev->dv_class_private = NULL;
2669 	dev->dv_class_suspend = NULL;
2670 	dev->dv_class_resume = NULL;
2671 	dev->dv_class_deregister = NULL;
2672 }
2673 
2674 bool
2675 device_active(device_t dev, devactive_t type)
2676 {
2677 	size_t i;
2678 
2679 	if (dev->dv_activity_count == 0)
2680 		return false;
2681 
2682 	for (i = 0; i < dev->dv_activity_count; ++i) {
2683 		if (dev->dv_activity_handlers[i] == NULL)
2684 			break;
2685 		(*dev->dv_activity_handlers[i])(dev, type);
2686 	}
2687 
2688 	return true;
2689 }
2690 
2691 bool
2692 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2693 {
2694 	void (**new_handlers)(device_t, devactive_t);
2695 	void (**old_handlers)(device_t, devactive_t);
2696 	size_t i, old_size, new_size;
2697 	int s;
2698 
2699 	old_handlers = dev->dv_activity_handlers;
2700 	old_size = dev->dv_activity_count;
2701 
2702 	KASSERT(old_size == 0 || old_handlers != NULL);
2703 
2704 	for (i = 0; i < old_size; ++i) {
2705 		KASSERT(old_handlers[i] != handler);
2706 		if (old_handlers[i] == NULL) {
2707 			old_handlers[i] = handler;
2708 			return true;
2709 		}
2710 	}
2711 
2712 	new_size = old_size + 4;
2713 	new_handlers = kmem_alloc(sizeof(void *) * new_size, KM_SLEEP);
2714 
2715 	for (i = 0; i < old_size; ++i)
2716 		new_handlers[i] = old_handlers[i];
2717 	new_handlers[old_size] = handler;
2718 	for (i = old_size+1; i < new_size; ++i)
2719 		new_handlers[i] = NULL;
2720 
2721 	s = splhigh();
2722 	dev->dv_activity_count = new_size;
2723 	dev->dv_activity_handlers = new_handlers;
2724 	splx(s);
2725 
2726 	if (old_size > 0)
2727 		kmem_free(old_handlers, sizeof(void *) * old_size);
2728 
2729 	return true;
2730 }
2731 
2732 void
2733 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2734 {
2735 	void (**old_handlers)(device_t, devactive_t);
2736 	size_t i, old_size;
2737 	int s;
2738 
2739 	old_handlers = dev->dv_activity_handlers;
2740 	old_size = dev->dv_activity_count;
2741 
2742 	for (i = 0; i < old_size; ++i) {
2743 		if (old_handlers[i] == handler)
2744 			break;
2745 		if (old_handlers[i] == NULL)
2746 			return; /* XXX panic? */
2747 	}
2748 
2749 	if (i == old_size)
2750 		return; /* XXX panic? */
2751 
2752 	for (; i < old_size - 1; ++i) {
2753 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
2754 			continue;
2755 
2756 		if (i == 0) {
2757 			s = splhigh();
2758 			dev->dv_activity_count = 0;
2759 			dev->dv_activity_handlers = NULL;
2760 			splx(s);
2761 			kmem_free(old_handlers, sizeof(void *) * old_size);
2762 		}
2763 		return;
2764 	}
2765 	old_handlers[i] = NULL;
2766 }
2767 
2768 /* Return true iff the device_t `dev' exists at generation `gen'. */
2769 static bool
2770 device_exists_at(device_t dv, devgen_t gen)
2771 {
2772 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
2773 	    dv->dv_add_gen <= gen;
2774 }
2775 
2776 static bool
2777 deviter_visits(const deviter_t *di, device_t dv)
2778 {
2779 	return device_exists_at(dv, di->di_gen);
2780 }
2781 
2782 /*
2783  * Device Iteration
2784  *
2785  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2786  *     each device_t's in the device tree.
2787  *
2788  * deviter_init(di, flags): initialize the device iterator `di'
2789  *     to "walk" the device tree.  deviter_next(di) will return
2790  *     the first device_t in the device tree, or NULL if there are
2791  *     no devices.
2792  *
2793  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2794  *     caller intends to modify the device tree by calling
2795  *     config_detach(9) on devices in the order that the iterator
2796  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2797  *     nearest the "root" of the device tree to be returned, first;
2798  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2799  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2800  *     indicating both that deviter_init() should not respect any
2801  *     locks on the device tree, and that deviter_next(di) may run
2802  *     in more than one LWP before the walk has finished.
2803  *
2804  *     Only one DEVITER_F_RW iterator may be in the device tree at
2805  *     once.
2806  *
2807  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2808  *
2809  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2810  *     DEVITER_F_LEAVES_FIRST are used in combination.
2811  *
2812  * deviter_first(di, flags): initialize the device iterator `di'
2813  *     and return the first device_t in the device tree, or NULL
2814  *     if there are no devices.  The statement
2815  *
2816  *         dv = deviter_first(di);
2817  *
2818  *     is shorthand for
2819  *
2820  *         deviter_init(di);
2821  *         dv = deviter_next(di);
2822  *
2823  * deviter_next(di): return the next device_t in the device tree,
2824  *     or NULL if there are no more devices.  deviter_next(di)
2825  *     is undefined if `di' was not initialized with deviter_init() or
2826  *     deviter_first().
2827  *
2828  * deviter_release(di): stops iteration (subsequent calls to
2829  *     deviter_next() will return NULL), releases any locks and
2830  *     resources held by the device iterator.
2831  *
2832  * Device iteration does not return device_t's in any particular
2833  * order.  An iterator will never return the same device_t twice.
2834  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2835  * is called repeatedly on the same `di', it will eventually return
2836  * NULL.  It is ok to attach/detach devices during device iteration.
2837  */
2838 void
2839 deviter_init(deviter_t *di, deviter_flags_t flags)
2840 {
2841 	device_t dv;
2842 
2843 	memset(di, 0, sizeof(*di));
2844 
2845 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
2846 		flags |= DEVITER_F_RW;
2847 
2848 	mutex_enter(&alldevs_lock);
2849 	if ((flags & DEVITER_F_RW) != 0)
2850 		alldevs_nwrite++;
2851 	else
2852 		alldevs_nread++;
2853 	di->di_gen = alldevs_gen++;
2854 	di->di_flags = flags;
2855 
2856 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2857 	case DEVITER_F_LEAVES_FIRST:
2858 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2859 			if (!deviter_visits(di, dv))
2860 				continue;
2861 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2862 		}
2863 		break;
2864 	case DEVITER_F_ROOT_FIRST:
2865 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2866 			if (!deviter_visits(di, dv))
2867 				continue;
2868 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2869 		}
2870 		break;
2871 	default:
2872 		break;
2873 	}
2874 
2875 	deviter_reinit(di);
2876 	mutex_exit(&alldevs_lock);
2877 }
2878 
2879 static void
2880 deviter_reinit(deviter_t *di)
2881 {
2882 
2883 	KASSERT(mutex_owned(&alldevs_lock));
2884 	if ((di->di_flags & DEVITER_F_RW) != 0)
2885 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2886 	else
2887 		di->di_prev = TAILQ_FIRST(&alldevs);
2888 }
2889 
2890 device_t
2891 deviter_first(deviter_t *di, deviter_flags_t flags)
2892 {
2893 
2894 	deviter_init(di, flags);
2895 	return deviter_next(di);
2896 }
2897 
2898 static device_t
2899 deviter_next2(deviter_t *di)
2900 {
2901 	device_t dv;
2902 
2903 	KASSERT(mutex_owned(&alldevs_lock));
2904 
2905 	dv = di->di_prev;
2906 
2907 	if (dv == NULL)
2908 		return NULL;
2909 
2910 	if ((di->di_flags & DEVITER_F_RW) != 0)
2911 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2912 	else
2913 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2914 
2915 	return dv;
2916 }
2917 
2918 static device_t
2919 deviter_next1(deviter_t *di)
2920 {
2921 	device_t dv;
2922 
2923 	KASSERT(mutex_owned(&alldevs_lock));
2924 
2925 	do {
2926 		dv = deviter_next2(di);
2927 	} while (dv != NULL && !deviter_visits(di, dv));
2928 
2929 	return dv;
2930 }
2931 
2932 device_t
2933 deviter_next(deviter_t *di)
2934 {
2935 	device_t dv = NULL;
2936 
2937 	mutex_enter(&alldevs_lock);
2938 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2939 	case 0:
2940 		dv = deviter_next1(di);
2941 		break;
2942 	case DEVITER_F_LEAVES_FIRST:
2943 		while (di->di_curdepth >= 0) {
2944 			if ((dv = deviter_next1(di)) == NULL) {
2945 				di->di_curdepth--;
2946 				deviter_reinit(di);
2947 			} else if (dv->dv_depth == di->di_curdepth)
2948 				break;
2949 		}
2950 		break;
2951 	case DEVITER_F_ROOT_FIRST:
2952 		while (di->di_curdepth <= di->di_maxdepth) {
2953 			if ((dv = deviter_next1(di)) == NULL) {
2954 				di->di_curdepth++;
2955 				deviter_reinit(di);
2956 			} else if (dv->dv_depth == di->di_curdepth)
2957 				break;
2958 		}
2959 		break;
2960 	default:
2961 		break;
2962 	}
2963 	mutex_exit(&alldevs_lock);
2964 
2965 	return dv;
2966 }
2967 
2968 void
2969 deviter_release(deviter_t *di)
2970 {
2971 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2972 
2973 	mutex_enter(&alldevs_lock);
2974 	if (rw)
2975 		--alldevs_nwrite;
2976 	else
2977 		--alldevs_nread;
2978 	/* XXX wake a garbage-collection thread */
2979 	mutex_exit(&alldevs_lock);
2980 }
2981 
2982 const char *
2983 cfdata_ifattr(const struct cfdata *cf)
2984 {
2985 	return cf->cf_pspec->cfp_iattr;
2986 }
2987 
2988 bool
2989 ifattr_match(const char *snull, const char *t)
2990 {
2991 	return (snull == NULL) || strcmp(snull, t) == 0;
2992 }
2993 
2994 void
2995 null_childdetached(device_t self, device_t child)
2996 {
2997 	/* do nothing */
2998 }
2999 
3000 static void
3001 sysctl_detach_setup(struct sysctllog **clog)
3002 {
3003 
3004 	sysctl_createv(clog, 0, NULL, NULL,
3005 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
3006 		CTLTYPE_BOOL, "detachall",
3007 		SYSCTL_DESCR("Detach all devices at shutdown"),
3008 		NULL, 0, &detachall, 0,
3009 		CTL_KERN, CTL_CREATE, CTL_EOL);
3010 }
3011