xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /* $NetBSD: subr_autoconf.c,v 1.238 2015/12/20 04:21:03 pgoyette 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 1.238 2015/12/20 04:21:03 pgoyette 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 extern 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_unlock(int);
176 static int config_alldevs_lock(void);
177 static void config_alldevs_enter(struct alldevs_foray *);
178 static void config_alldevs_exit(struct alldevs_foray *);
179 static void config_add_attrib_dict(device_t);
180 
181 static void config_collect_garbage(struct devicelist *);
182 static void config_dump_garbage(struct devicelist *);
183 
184 static void pmflock_debug(device_t, const char *, int);
185 
186 static device_t deviter_next1(deviter_t *);
187 static void deviter_reinit(deviter_t *);
188 
189 struct deferred_config {
190 	TAILQ_ENTRY(deferred_config) dc_queue;
191 	device_t dc_dev;
192 	void (*dc_func)(device_t);
193 };
194 
195 TAILQ_HEAD(deferred_config_head, deferred_config);
196 
197 struct deferred_config_head deferred_config_queue =
198 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
199 struct deferred_config_head interrupt_config_queue =
200 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
201 int interrupt_config_threads = 8;
202 struct deferred_config_head mountroot_config_queue =
203 	TAILQ_HEAD_INITIALIZER(mountroot_config_queue);
204 int mountroot_config_threads = 2;
205 static lwp_t **mountroot_config_lwpids;
206 static size_t mountroot_config_lwpids_size;
207 static bool root_is_mounted = false;
208 
209 static void config_process_deferred(struct deferred_config_head *, device_t);
210 
211 /* Hooks to finalize configuration once all real devices have been found. */
212 struct finalize_hook {
213 	TAILQ_ENTRY(finalize_hook) f_list;
214 	int (*f_func)(device_t);
215 	device_t f_dev;
216 };
217 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
218 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
219 static int config_finalize_done;
220 
221 /* list of all devices */
222 static struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
223 static kmutex_t alldevs_mtx;
224 static volatile bool alldevs_garbage = false;
225 static volatile devgen_t alldevs_gen = 1;
226 static volatile int alldevs_nread = 0;
227 static volatile int alldevs_nwrite = 0;
228 
229 static int config_pending;		/* semaphore for mountroot */
230 static kmutex_t config_misc_lock;
231 static kcondvar_t config_misc_cv;
232 
233 static bool detachall = false;
234 
235 #define	STREQ(s1, s2)			\
236 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
237 
238 static bool config_initialized = false;	/* config_init() has been called. */
239 
240 static int config_do_twiddle;
241 static callout_t config_twiddle_ch;
242 
243 static void sysctl_detach_setup(struct sysctllog **);
244 
245 int no_devmon_insert(const char *, prop_dictionary_t);
246 int (*devmon_insert_vec)(const char *, prop_dictionary_t) = no_devmon_insert;
247 
248 typedef int (*cfdriver_fn)(struct cfdriver *);
249 static int
250 frob_cfdrivervec(struct cfdriver * const *cfdriverv,
251 	cfdriver_fn drv_do, cfdriver_fn drv_undo,
252 	const char *style, bool dopanic)
253 {
254 	void (*pr)(const char *, ...) __printflike(1, 2) =
255 	    dopanic ? panic : printf;
256 	int i, error = 0, e2 __diagused;
257 
258 	for (i = 0; cfdriverv[i] != NULL; i++) {
259 		if ((error = drv_do(cfdriverv[i])) != 0) {
260 			pr("configure: `%s' driver %s failed: %d",
261 			    cfdriverv[i]->cd_name, style, error);
262 			goto bad;
263 		}
264 	}
265 
266 	KASSERT(error == 0);
267 	return 0;
268 
269  bad:
270 	printf("\n");
271 	for (i--; i >= 0; i--) {
272 		e2 = drv_undo(cfdriverv[i]);
273 		KASSERT(e2 == 0);
274 	}
275 
276 	return error;
277 }
278 
279 typedef int (*cfattach_fn)(const char *, struct cfattach *);
280 static int
281 frob_cfattachvec(const struct cfattachinit *cfattachv,
282 	cfattach_fn att_do, cfattach_fn att_undo,
283 	const char *style, bool dopanic)
284 {
285 	const struct cfattachinit *cfai = NULL;
286 	void (*pr)(const char *, ...) __printflike(1, 2) =
287 	    dopanic ? panic : printf;
288 	int j = 0, error = 0, e2 __diagused;
289 
290 	for (cfai = &cfattachv[0]; cfai->cfai_name != NULL; cfai++) {
291 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
292 			if ((error = att_do(cfai->cfai_name,
293 			    cfai->cfai_list[j])) != 0) {
294 				pr("configure: attachment `%s' "
295 				    "of `%s' driver %s failed: %d",
296 				    cfai->cfai_list[j]->ca_name,
297 				    cfai->cfai_name, style, error);
298 				goto bad;
299 			}
300 		}
301 	}
302 
303 	KASSERT(error == 0);
304 	return 0;
305 
306  bad:
307 	/*
308 	 * Rollback in reverse order.  dunno if super-important, but
309 	 * do that anyway.  Although the code looks a little like
310 	 * someone did a little integration (in the math sense).
311 	 */
312 	printf("\n");
313 	if (cfai) {
314 		bool last;
315 
316 		for (last = false; last == false; ) {
317 			if (cfai == &cfattachv[0])
318 				last = true;
319 			for (j--; j >= 0; j--) {
320 				e2 = att_undo(cfai->cfai_name,
321 				    cfai->cfai_list[j]);
322 				KASSERT(e2 == 0);
323 			}
324 			if (!last) {
325 				cfai--;
326 				for (j = 0; cfai->cfai_list[j] != NULL; j++)
327 					;
328 			}
329 		}
330 	}
331 
332 	return error;
333 }
334 
335 /*
336  * Initialize the autoconfiguration data structures.  Normally this
337  * is done by configure(), but some platforms need to do this very
338  * early (to e.g. initialize the console).
339  */
340 void
341 config_init(void)
342 {
343 
344 	KASSERT(config_initialized == false);
345 
346 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_VM);
347 
348 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
349 	cv_init(&config_misc_cv, "cfgmisc");
350 
351 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
352 
353 	frob_cfdrivervec(cfdriver_list_initial,
354 	    config_cfdriver_attach, NULL, "bootstrap", true);
355 	frob_cfattachvec(cfattachinit,
356 	    config_cfattach_attach, NULL, "bootstrap", true);
357 
358 	initcftable.ct_cfdata = cfdata;
359 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
360 
361 	config_initialized = true;
362 }
363 
364 /*
365  * Init or fini drivers and attachments.  Either all or none
366  * are processed (via rollback).  It would be nice if this were
367  * atomic to outside consumers, but with the current state of
368  * locking ...
369  */
370 int
371 config_init_component(struct cfdriver * const *cfdriverv,
372 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
373 {
374 	int error;
375 
376 	if ((error = frob_cfdrivervec(cfdriverv,
377 	    config_cfdriver_attach, config_cfdriver_detach, "init", false))!= 0)
378 		return error;
379 	if ((error = frob_cfattachvec(cfattachv,
380 	    config_cfattach_attach, config_cfattach_detach,
381 	    "init", false)) != 0) {
382 		frob_cfdrivervec(cfdriverv,
383 	            config_cfdriver_detach, NULL, "init rollback", true);
384 		return error;
385 	}
386 	if ((error = config_cfdata_attach(cfdatav, 1)) != 0) {
387 		frob_cfattachvec(cfattachv,
388 		    config_cfattach_detach, NULL, "init rollback", true);
389 		frob_cfdrivervec(cfdriverv,
390 	            config_cfdriver_detach, NULL, "init rollback", true);
391 		return error;
392 	}
393 
394 	return 0;
395 }
396 
397 int
398 config_fini_component(struct cfdriver * const *cfdriverv,
399 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
400 {
401 	int error;
402 
403 	if ((error = config_cfdata_detach(cfdatav)) != 0)
404 		return error;
405 	if ((error = frob_cfattachvec(cfattachv,
406 	    config_cfattach_detach, config_cfattach_attach,
407 	    "fini", false)) != 0) {
408 		if (config_cfdata_attach(cfdatav, 0) != 0)
409 			panic("config_cfdata fini rollback failed");
410 		return error;
411 	}
412 	if ((error = frob_cfdrivervec(cfdriverv,
413 	    config_cfdriver_detach, config_cfdriver_attach,
414 	    "fini", false)) != 0) {
415 		frob_cfattachvec(cfattachv,
416 	            config_cfattach_attach, NULL, "fini rollback", true);
417 		if (config_cfdata_attach(cfdatav, 0) != 0)
418 			panic("config_cfdata fini rollback failed");
419 		return error;
420 	}
421 
422 	return 0;
423 }
424 
425 void
426 config_init_mi(void)
427 {
428 
429 	if (!config_initialized)
430 		config_init();
431 
432 	sysctl_detach_setup(NULL);
433 }
434 
435 void
436 config_deferred(device_t dev)
437 {
438 	config_process_deferred(&deferred_config_queue, dev);
439 	config_process_deferred(&interrupt_config_queue, dev);
440 	config_process_deferred(&mountroot_config_queue, dev);
441 }
442 
443 static void
444 config_interrupts_thread(void *cookie)
445 {
446 	struct deferred_config *dc;
447 
448 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
449 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
450 		(*dc->dc_func)(dc->dc_dev);
451 		config_pending_decr(dc->dc_dev);
452 		kmem_free(dc, sizeof(*dc));
453 	}
454 	kthread_exit(0);
455 }
456 
457 void
458 config_create_interruptthreads(void)
459 {
460 	int i;
461 
462 	for (i = 0; i < interrupt_config_threads; i++) {
463 		(void)kthread_create(PRI_NONE, 0, NULL,
464 		    config_interrupts_thread, NULL, NULL, "configintr");
465 	}
466 }
467 
468 static void
469 config_mountroot_thread(void *cookie)
470 {
471 	struct deferred_config *dc;
472 
473 	while ((dc = TAILQ_FIRST(&mountroot_config_queue)) != NULL) {
474 		TAILQ_REMOVE(&mountroot_config_queue, dc, dc_queue);
475 		(*dc->dc_func)(dc->dc_dev);
476 		kmem_free(dc, sizeof(*dc));
477 	}
478 	kthread_exit(0);
479 }
480 
481 void
482 config_create_mountrootthreads(void)
483 {
484 	int i;
485 
486 	if (!root_is_mounted)
487 		root_is_mounted = true;
488 
489 	mountroot_config_lwpids_size = sizeof(mountroot_config_lwpids) *
490 				       mountroot_config_threads;
491 	mountroot_config_lwpids = kmem_alloc(mountroot_config_lwpids_size,
492 					     KM_NOSLEEP);
493 	KASSERT(mountroot_config_lwpids);
494 	for (i = 0; i < mountroot_config_threads; i++) {
495 		mountroot_config_lwpids[i] = 0;
496 		(void)kthread_create(PRI_NONE, KTHREAD_MUSTJOIN, NULL,
497 				     config_mountroot_thread, NULL,
498 				     &mountroot_config_lwpids[i],
499 				     "configroot");
500 	}
501 }
502 
503 void
504 config_finalize_mountroot(void)
505 {
506 	int i, error;
507 
508 	for (i = 0; i < mountroot_config_threads; i++) {
509 		if (mountroot_config_lwpids[i] == 0)
510 			continue;
511 
512 		error = kthread_join(mountroot_config_lwpids[i]);
513 		if (error)
514 			printf("%s: thread %x joined with error %d\n",
515 			       __func__, i, error);
516 	}
517 	kmem_free(mountroot_config_lwpids, mountroot_config_lwpids_size);
518 }
519 
520 /*
521  * Announce device attach/detach to userland listeners.
522  */
523 
524 int
525 no_devmon_insert(const char *name, prop_dictionary_t p)
526 {
527 
528 	return ENODEV;
529 }
530 
531 static void
532 devmon_report_device(device_t dev, bool isattach)
533 {
534 	prop_dictionary_t ev;
535 	const char *parent;
536 	const char *what;
537 	device_t pdev = device_parent(dev);
538 
539 	/* If currently no drvctl device, just return */
540 	if (devmon_insert_vec == no_devmon_insert)
541 		return;
542 
543 	ev = prop_dictionary_create();
544 	if (ev == NULL)
545 		return;
546 
547 	what = (isattach ? "device-attach" : "device-detach");
548 	parent = (pdev == NULL ? "root" : device_xname(pdev));
549 	if (!prop_dictionary_set_cstring(ev, "device", device_xname(dev)) ||
550 	    !prop_dictionary_set_cstring(ev, "parent", parent)) {
551 		prop_object_release(ev);
552 		return;
553 	}
554 
555 	if ((*devmon_insert_vec)(what, ev) != 0)
556 		prop_object_release(ev);
557 }
558 
559 /*
560  * Add a cfdriver to the system.
561  */
562 int
563 config_cfdriver_attach(struct cfdriver *cd)
564 {
565 	struct cfdriver *lcd;
566 
567 	/* Make sure this driver isn't already in the system. */
568 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
569 		if (STREQ(lcd->cd_name, cd->cd_name))
570 			return EEXIST;
571 	}
572 
573 	LIST_INIT(&cd->cd_attach);
574 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
575 
576 	return 0;
577 }
578 
579 /*
580  * Remove a cfdriver from the system.
581  */
582 int
583 config_cfdriver_detach(struct cfdriver *cd)
584 {
585 	struct alldevs_foray af;
586 	int i, rc = 0;
587 
588 	config_alldevs_enter(&af);
589 	/* Make sure there are no active instances. */
590 	for (i = 0; i < cd->cd_ndevs; i++) {
591 		if (cd->cd_devs[i] != NULL) {
592 			rc = EBUSY;
593 			break;
594 		}
595 	}
596 	config_alldevs_exit(&af);
597 
598 	if (rc != 0)
599 		return rc;
600 
601 	/* ...and no attachments loaded. */
602 	if (LIST_EMPTY(&cd->cd_attach) == 0)
603 		return EBUSY;
604 
605 	LIST_REMOVE(cd, cd_list);
606 
607 	KASSERT(cd->cd_devs == NULL);
608 
609 	return 0;
610 }
611 
612 /*
613  * Look up a cfdriver by name.
614  */
615 struct cfdriver *
616 config_cfdriver_lookup(const char *name)
617 {
618 	struct cfdriver *cd;
619 
620 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
621 		if (STREQ(cd->cd_name, name))
622 			return cd;
623 	}
624 
625 	return NULL;
626 }
627 
628 /*
629  * Add a cfattach to the specified driver.
630  */
631 int
632 config_cfattach_attach(const char *driver, struct cfattach *ca)
633 {
634 	struct cfattach *lca;
635 	struct cfdriver *cd;
636 
637 	cd = config_cfdriver_lookup(driver);
638 	if (cd == NULL)
639 		return ESRCH;
640 
641 	/* Make sure this attachment isn't already on this driver. */
642 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
643 		if (STREQ(lca->ca_name, ca->ca_name))
644 			return EEXIST;
645 	}
646 
647 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
648 
649 	return 0;
650 }
651 
652 /*
653  * Remove a cfattach from the specified driver.
654  */
655 int
656 config_cfattach_detach(const char *driver, struct cfattach *ca)
657 {
658 	struct alldevs_foray af;
659 	struct cfdriver *cd;
660 	device_t dev;
661 	int i, rc = 0;
662 
663 	cd = config_cfdriver_lookup(driver);
664 	if (cd == NULL)
665 		return ESRCH;
666 
667 	config_alldevs_enter(&af);
668 	/* Make sure there are no active instances. */
669 	for (i = 0; i < cd->cd_ndevs; i++) {
670 		if ((dev = cd->cd_devs[i]) == NULL)
671 			continue;
672 		if (dev->dv_cfattach == ca) {
673 			rc = EBUSY;
674 			break;
675 		}
676 	}
677 	config_alldevs_exit(&af);
678 
679 	if (rc != 0)
680 		return rc;
681 
682 	LIST_REMOVE(ca, ca_list);
683 
684 	return 0;
685 }
686 
687 /*
688  * Look up a cfattach by name.
689  */
690 static struct cfattach *
691 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
692 {
693 	struct cfattach *ca;
694 
695 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
696 		if (STREQ(ca->ca_name, atname))
697 			return ca;
698 	}
699 
700 	return NULL;
701 }
702 
703 /*
704  * Look up a cfattach by driver/attachment name.
705  */
706 struct cfattach *
707 config_cfattach_lookup(const char *name, const char *atname)
708 {
709 	struct cfdriver *cd;
710 
711 	cd = config_cfdriver_lookup(name);
712 	if (cd == NULL)
713 		return NULL;
714 
715 	return config_cfattach_lookup_cd(cd, atname);
716 }
717 
718 /*
719  * Apply the matching function and choose the best.  This is used
720  * a few times and we want to keep the code small.
721  */
722 static void
723 mapply(struct matchinfo *m, cfdata_t cf)
724 {
725 	int pri;
726 
727 	if (m->fn != NULL) {
728 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
729 	} else {
730 		pri = config_match(m->parent, cf, m->aux);
731 	}
732 	if (pri > m->pri) {
733 		m->match = cf;
734 		m->pri = pri;
735 	}
736 }
737 
738 int
739 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
740 {
741 	const struct cfiattrdata *ci;
742 	const struct cflocdesc *cl;
743 	int nlocs, i;
744 
745 	ci = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
746 	KASSERT(ci);
747 	nlocs = ci->ci_loclen;
748 	KASSERT(!nlocs || locs);
749 	for (i = 0; i < nlocs; i++) {
750 		cl = &ci->ci_locdesc[i];
751 		if (cl->cld_defaultstr != NULL &&
752 		    cf->cf_loc[i] == cl->cld_default)
753 			continue;
754 		if (cf->cf_loc[i] == locs[i])
755 			continue;
756 		return 0;
757 	}
758 
759 	return config_match(parent, cf, aux);
760 }
761 
762 /*
763  * Helper function: check whether the driver supports the interface attribute
764  * and return its descriptor structure.
765  */
766 static const struct cfiattrdata *
767 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
768 {
769 	const struct cfiattrdata * const *cpp;
770 
771 	if (cd->cd_attrs == NULL)
772 		return 0;
773 
774 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
775 		if (STREQ((*cpp)->ci_name, ia)) {
776 			/* Match. */
777 			return *cpp;
778 		}
779 	}
780 	return 0;
781 }
782 
783 /*
784  * Lookup an interface attribute description by name.
785  * If the driver is given, consider only its supported attributes.
786  */
787 const struct cfiattrdata *
788 cfiattr_lookup(const char *name, const struct cfdriver *cd)
789 {
790 	const struct cfdriver *d;
791 	const struct cfiattrdata *ia;
792 
793 	if (cd)
794 		return cfdriver_get_iattr(cd, name);
795 
796 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
797 		ia = cfdriver_get_iattr(d, name);
798 		if (ia)
799 			return ia;
800 	}
801 	return 0;
802 }
803 
804 /*
805  * Determine if `parent' is a potential parent for a device spec based
806  * on `cfp'.
807  */
808 static int
809 cfparent_match(const device_t parent, const struct cfparent *cfp)
810 {
811 	struct cfdriver *pcd;
812 
813 	/* We don't match root nodes here. */
814 	if (cfp == NULL)
815 		return 0;
816 
817 	pcd = parent->dv_cfdriver;
818 	KASSERT(pcd != NULL);
819 
820 	/*
821 	 * First, ensure this parent has the correct interface
822 	 * attribute.
823 	 */
824 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
825 		return 0;
826 
827 	/*
828 	 * If no specific parent device instance was specified (i.e.
829 	 * we're attaching to the attribute only), we're done!
830 	 */
831 	if (cfp->cfp_parent == NULL)
832 		return 1;
833 
834 	/*
835 	 * Check the parent device's name.
836 	 */
837 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
838 		return 0;	/* not the same parent */
839 
840 	/*
841 	 * Make sure the unit number matches.
842 	 */
843 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
844 	    cfp->cfp_unit == parent->dv_unit)
845 		return 1;
846 
847 	/* Unit numbers don't match. */
848 	return 0;
849 }
850 
851 /*
852  * Helper for config_cfdata_attach(): check all devices whether it could be
853  * parent any attachment in the config data table passed, and rescan.
854  */
855 static void
856 rescan_with_cfdata(const struct cfdata *cf)
857 {
858 	device_t d;
859 	const struct cfdata *cf1;
860 	deviter_t di;
861 
862 
863 	/*
864 	 * "alldevs" is likely longer than a modules's cfdata, so make it
865 	 * the outer loop.
866 	 */
867 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
868 
869 		if (!(d->dv_cfattach->ca_rescan))
870 			continue;
871 
872 		for (cf1 = cf; cf1->cf_name; cf1++) {
873 
874 			if (!cfparent_match(d, cf1->cf_pspec))
875 				continue;
876 
877 			(*d->dv_cfattach->ca_rescan)(d,
878 				cfdata_ifattr(cf1), cf1->cf_loc);
879 
880 			config_deferred(d);
881 		}
882 	}
883 	deviter_release(&di);
884 }
885 
886 /*
887  * Attach a supplemental config data table and rescan potential
888  * parent devices if required.
889  */
890 int
891 config_cfdata_attach(cfdata_t cf, int scannow)
892 {
893 	struct cftable *ct;
894 
895 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
896 	ct->ct_cfdata = cf;
897 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
898 
899 	if (scannow)
900 		rescan_with_cfdata(cf);
901 
902 	return 0;
903 }
904 
905 /*
906  * Helper for config_cfdata_detach: check whether a device is
907  * found through any attachment in the config data table.
908  */
909 static int
910 dev_in_cfdata(device_t d, cfdata_t cf)
911 {
912 	const struct cfdata *cf1;
913 
914 	for (cf1 = cf; cf1->cf_name; cf1++)
915 		if (d->dv_cfdata == cf1)
916 			return 1;
917 
918 	return 0;
919 }
920 
921 /*
922  * Detach a supplemental config data table. Detach all devices found
923  * through that table (and thus keeping references to it) before.
924  */
925 int
926 config_cfdata_detach(cfdata_t cf)
927 {
928 	device_t d;
929 	int error = 0;
930 	struct cftable *ct;
931 	deviter_t di;
932 
933 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
934 	     d = deviter_next(&di)) {
935 		if (!dev_in_cfdata(d, cf))
936 			continue;
937 		if ((error = config_detach(d, 0)) != 0)
938 			break;
939 	}
940 	deviter_release(&di);
941 	if (error) {
942 		aprint_error_dev(d, "unable to detach instance\n");
943 		return error;
944 	}
945 
946 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
947 		if (ct->ct_cfdata == cf) {
948 			TAILQ_REMOVE(&allcftables, ct, ct_list);
949 			kmem_free(ct, sizeof(*ct));
950 			return 0;
951 		}
952 	}
953 
954 	/* not found -- shouldn't happen */
955 	return EINVAL;
956 }
957 
958 /*
959  * Invoke the "match" routine for a cfdata entry on behalf of
960  * an external caller, usually a "submatch" routine.
961  */
962 int
963 config_match(device_t parent, cfdata_t cf, void *aux)
964 {
965 	struct cfattach *ca;
966 
967 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
968 	if (ca == NULL) {
969 		/* No attachment for this entry, oh well. */
970 		return 0;
971 	}
972 
973 	return (*ca->ca_match)(parent, cf, aux);
974 }
975 
976 /*
977  * Iterate over all potential children of some device, calling the given
978  * function (default being the child's match function) for each one.
979  * Nonzero returns are matches; the highest value returned is considered
980  * the best match.  Return the `found child' if we got a match, or NULL
981  * otherwise.  The `aux' pointer is simply passed on through.
982  *
983  * Note that this function is designed so that it can be used to apply
984  * an arbitrary function to all potential children (its return value
985  * can be ignored).
986  */
987 cfdata_t
988 config_search_loc(cfsubmatch_t fn, device_t parent,
989 		  const char *ifattr, const int *locs, void *aux)
990 {
991 	struct cftable *ct;
992 	cfdata_t cf;
993 	struct matchinfo m;
994 
995 	KASSERT(config_initialized);
996 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
997 
998 	m.fn = fn;
999 	m.parent = parent;
1000 	m.locs = locs;
1001 	m.aux = aux;
1002 	m.match = NULL;
1003 	m.pri = 0;
1004 
1005 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1006 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1007 
1008 			/* We don't match root nodes here. */
1009 			if (!cf->cf_pspec)
1010 				continue;
1011 
1012 			/*
1013 			 * Skip cf if no longer eligible, otherwise scan
1014 			 * through parents for one matching `parent', and
1015 			 * try match function.
1016 			 */
1017 			if (cf->cf_fstate == FSTATE_FOUND)
1018 				continue;
1019 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
1020 			    cf->cf_fstate == FSTATE_DSTAR)
1021 				continue;
1022 
1023 			/*
1024 			 * If an interface attribute was specified,
1025 			 * consider only children which attach to
1026 			 * that attribute.
1027 			 */
1028 			if (ifattr && !STREQ(ifattr, cfdata_ifattr(cf)))
1029 				continue;
1030 
1031 			if (cfparent_match(parent, cf->cf_pspec))
1032 				mapply(&m, cf);
1033 		}
1034 	}
1035 	return m.match;
1036 }
1037 
1038 cfdata_t
1039 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
1040     void *aux)
1041 {
1042 
1043 	return config_search_loc(fn, parent, ifattr, NULL, aux);
1044 }
1045 
1046 /*
1047  * Find the given root device.
1048  * This is much like config_search, but there is no parent.
1049  * Don't bother with multiple cfdata tables; the root node
1050  * must always be in the initial table.
1051  */
1052 cfdata_t
1053 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
1054 {
1055 	cfdata_t cf;
1056 	const short *p;
1057 	struct matchinfo m;
1058 
1059 	m.fn = fn;
1060 	m.parent = ROOT;
1061 	m.aux = aux;
1062 	m.match = NULL;
1063 	m.pri = 0;
1064 	m.locs = 0;
1065 	/*
1066 	 * Look at root entries for matching name.  We do not bother
1067 	 * with found-state here since only one root should ever be
1068 	 * searched (and it must be done first).
1069 	 */
1070 	for (p = cfroots; *p >= 0; p++) {
1071 		cf = &cfdata[*p];
1072 		if (strcmp(cf->cf_name, rootname) == 0)
1073 			mapply(&m, cf);
1074 	}
1075 	return m.match;
1076 }
1077 
1078 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
1079 
1080 /*
1081  * The given `aux' argument describes a device that has been found
1082  * on the given parent, but not necessarily configured.  Locate the
1083  * configuration data for that device (using the submatch function
1084  * provided, or using candidates' cd_match configuration driver
1085  * functions) and attach it, and return its device_t.  If the device was
1086  * not configured, call the given `print' function and return NULL.
1087  */
1088 device_t
1089 config_found_sm_loc(device_t parent,
1090 		const char *ifattr, const int *locs, void *aux,
1091 		cfprint_t print, cfsubmatch_t submatch)
1092 {
1093 	cfdata_t cf;
1094 
1095 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
1096 		return(config_attach_loc(parent, cf, locs, aux, print));
1097 	if (print) {
1098 		if (config_do_twiddle && cold)
1099 			twiddle();
1100 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
1101 	}
1102 
1103 	/*
1104 	 * This has the effect of mixing in a single timestamp to the
1105 	 * entropy pool.  Experiments indicate the estimator will almost
1106 	 * always attribute one bit of entropy to this sample; analysis
1107 	 * of device attach/detach timestamps on FreeBSD indicates 4
1108 	 * bits of entropy/sample so this seems appropriately conservative.
1109 	 */
1110 	rnd_add_uint32(&rnd_autoconf_source, 0);
1111 	return NULL;
1112 }
1113 
1114 device_t
1115 config_found_ia(device_t parent, const char *ifattr, void *aux,
1116     cfprint_t print)
1117 {
1118 
1119 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
1120 }
1121 
1122 device_t
1123 config_found(device_t parent, void *aux, cfprint_t print)
1124 {
1125 
1126 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
1127 }
1128 
1129 /*
1130  * As above, but for root devices.
1131  */
1132 device_t
1133 config_rootfound(const char *rootname, void *aux)
1134 {
1135 	cfdata_t cf;
1136 
1137 	if ((cf = config_rootsearch(NULL, rootname, aux)) != NULL)
1138 		return config_attach(ROOT, cf, aux, NULL);
1139 	aprint_error("root device %s not configured\n", rootname);
1140 	return NULL;
1141 }
1142 
1143 /* just like sprintf(buf, "%d") except that it works from the end */
1144 static char *
1145 number(char *ep, int n)
1146 {
1147 
1148 	*--ep = 0;
1149 	while (n >= 10) {
1150 		*--ep = (n % 10) + '0';
1151 		n /= 10;
1152 	}
1153 	*--ep = n + '0';
1154 	return ep;
1155 }
1156 
1157 /*
1158  * Expand the size of the cd_devs array if necessary.
1159  *
1160  * The caller must hold alldevs_mtx. config_makeroom() may release and
1161  * re-acquire alldevs_mtx, so callers should re-check conditions such
1162  * as alldevs_nwrite == 0 and alldevs_nread == 0 when config_makeroom()
1163  * returns.
1164  */
1165 static void
1166 config_makeroom(int n, struct cfdriver *cd)
1167 {
1168 	int ondevs, nndevs;
1169 	device_t *osp, *nsp;
1170 
1171 	alldevs_nwrite++;
1172 
1173 	for (nndevs = MAX(4, cd->cd_ndevs); nndevs <= n; nndevs += nndevs)
1174 		;
1175 
1176 	while (n >= cd->cd_ndevs) {
1177 		/*
1178 		 * Need to expand the array.
1179 		 */
1180 		ondevs = cd->cd_ndevs;
1181 		osp = cd->cd_devs;
1182 
1183 		/* Release alldevs_mtx around allocation, which may
1184 		 * sleep.
1185 		 */
1186 		mutex_exit(&alldevs_mtx);
1187 		nsp = kmem_alloc(sizeof(device_t[nndevs]), KM_SLEEP);
1188 		if (nsp == NULL)
1189 			panic("%s: could not expand cd_devs", __func__);
1190 		mutex_enter(&alldevs_mtx);
1191 
1192 		/* If another thread moved the array while we did
1193 		 * not hold alldevs_mtx, try again.
1194 		 */
1195 		if (cd->cd_devs != osp) {
1196 			mutex_exit(&alldevs_mtx);
1197 			kmem_free(nsp, sizeof(device_t[nndevs]));
1198 			mutex_enter(&alldevs_mtx);
1199 			continue;
1200 		}
1201 
1202 		memset(nsp + ondevs, 0, sizeof(device_t[nndevs - ondevs]));
1203 		if (ondevs != 0)
1204 			memcpy(nsp, cd->cd_devs, sizeof(device_t[ondevs]));
1205 
1206 		cd->cd_ndevs = nndevs;
1207 		cd->cd_devs = nsp;
1208 		if (ondevs != 0) {
1209 			mutex_exit(&alldevs_mtx);
1210 			kmem_free(osp, sizeof(device_t[ondevs]));
1211 			mutex_enter(&alldevs_mtx);
1212 		}
1213 	}
1214 	alldevs_nwrite--;
1215 }
1216 
1217 /*
1218  * Put dev into the devices list.
1219  */
1220 static void
1221 config_devlink(device_t dev)
1222 {
1223 	int s;
1224 
1225 	s = config_alldevs_lock();
1226 
1227 	KASSERT(device_cfdriver(dev)->cd_devs[dev->dv_unit] == dev);
1228 
1229 	dev->dv_add_gen = alldevs_gen;
1230 	/* It is safe to add a device to the tail of the list while
1231 	 * readers and writers are in the list.
1232 	 */
1233 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);
1234 	config_alldevs_unlock(s);
1235 }
1236 
1237 static void
1238 config_devfree(device_t dev)
1239 {
1240 	int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
1241 
1242 	if (dev->dv_cfattach->ca_devsize > 0)
1243 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
1244 	if (priv)
1245 		kmem_free(dev, sizeof(*dev));
1246 }
1247 
1248 /*
1249  * Caller must hold alldevs_mtx.
1250  */
1251 static void
1252 config_devunlink(device_t dev, struct devicelist *garbage)
1253 {
1254 	struct device_garbage *dg = &dev->dv_garbage;
1255 	cfdriver_t cd = device_cfdriver(dev);
1256 	int i;
1257 
1258 	KASSERT(mutex_owned(&alldevs_mtx));
1259 
1260  	/* Unlink from device list.  Link to garbage list. */
1261 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1262 	TAILQ_INSERT_TAIL(garbage, dev, dv_list);
1263 
1264 	/* Remove from cfdriver's array. */
1265 	cd->cd_devs[dev->dv_unit] = NULL;
1266 
1267 	/*
1268 	 * If the device now has no units in use, unlink its softc array.
1269 	 */
1270 	for (i = 0; i < cd->cd_ndevs; i++) {
1271 		if (cd->cd_devs[i] != NULL)
1272 			break;
1273 	}
1274 	/* Nothing found.  Unlink, now.  Deallocate, later. */
1275 	if (i == cd->cd_ndevs) {
1276 		dg->dg_ndevs = cd->cd_ndevs;
1277 		dg->dg_devs = cd->cd_devs;
1278 		cd->cd_devs = NULL;
1279 		cd->cd_ndevs = 0;
1280 	}
1281 }
1282 
1283 static void
1284 config_devdelete(device_t dev)
1285 {
1286 	struct device_garbage *dg = &dev->dv_garbage;
1287 	device_lock_t dvl = device_getlock(dev);
1288 
1289 	if (dg->dg_devs != NULL)
1290 		kmem_free(dg->dg_devs, sizeof(device_t[dg->dg_ndevs]));
1291 
1292 	cv_destroy(&dvl->dvl_cv);
1293 	mutex_destroy(&dvl->dvl_mtx);
1294 
1295 	KASSERT(dev->dv_properties != NULL);
1296 	prop_object_release(dev->dv_properties);
1297 
1298 	if (dev->dv_activity_handlers)
1299 		panic("%s with registered handlers", __func__);
1300 
1301 	if (dev->dv_locators) {
1302 		size_t amount = *--dev->dv_locators;
1303 		kmem_free(dev->dv_locators, amount);
1304 	}
1305 
1306 	config_devfree(dev);
1307 }
1308 
1309 static int
1310 config_unit_nextfree(cfdriver_t cd, cfdata_t cf)
1311 {
1312 	int unit;
1313 
1314 	if (cf->cf_fstate == FSTATE_STAR) {
1315 		for (unit = cf->cf_unit; unit < cd->cd_ndevs; unit++)
1316 			if (cd->cd_devs[unit] == NULL)
1317 				break;
1318 		/*
1319 		 * unit is now the unit of the first NULL device pointer,
1320 		 * or max(cd->cd_ndevs,cf->cf_unit).
1321 		 */
1322 	} else {
1323 		unit = cf->cf_unit;
1324 		if (unit < cd->cd_ndevs && cd->cd_devs[unit] != NULL)
1325 			unit = -1;
1326 	}
1327 	return unit;
1328 }
1329 
1330 static int
1331 config_unit_alloc(device_t dev, cfdriver_t cd, cfdata_t cf)
1332 {
1333 	struct alldevs_foray af;
1334 	int unit;
1335 
1336 	config_alldevs_enter(&af);
1337 	for (;;) {
1338 		unit = config_unit_nextfree(cd, cf);
1339 		if (unit == -1)
1340 			break;
1341 		if (unit < cd->cd_ndevs) {
1342 			cd->cd_devs[unit] = dev;
1343 			dev->dv_unit = unit;
1344 			break;
1345 		}
1346 		config_makeroom(unit, cd);
1347 	}
1348 	config_alldevs_exit(&af);
1349 
1350 	return unit;
1351 }
1352 
1353 static device_t
1354 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1355 {
1356 	cfdriver_t cd;
1357 	cfattach_t ca;
1358 	size_t lname, lunit;
1359 	const char *xunit;
1360 	int myunit;
1361 	char num[10];
1362 	device_t dev;
1363 	void *dev_private;
1364 	const struct cfiattrdata *ia;
1365 	device_lock_t dvl;
1366 
1367 	cd = config_cfdriver_lookup(cf->cf_name);
1368 	if (cd == NULL)
1369 		return NULL;
1370 
1371 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1372 	if (ca == NULL)
1373 		return NULL;
1374 
1375 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
1376 	    ca->ca_devsize < sizeof(struct device))
1377 		panic("config_devalloc: %s (%zu < %zu)", cf->cf_atname,
1378 		    ca->ca_devsize, sizeof(struct device));
1379 
1380 	/* get memory for all device vars */
1381 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
1382 	if (ca->ca_devsize > 0) {
1383 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
1384 		if (dev_private == NULL)
1385 			panic("config_devalloc: memory allocation for device softc failed");
1386 	} else {
1387 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1388 		dev_private = NULL;
1389 	}
1390 
1391 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
1392 		dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
1393 	} else {
1394 		dev = dev_private;
1395 #ifdef DIAGNOSTIC
1396 		printf("%s has not been converted to device_t\n", cd->cd_name);
1397 #endif
1398 	}
1399 	if (dev == NULL)
1400 		panic("config_devalloc: memory allocation for device_t failed");
1401 
1402 	dev->dv_class = cd->cd_class;
1403 	dev->dv_cfdata = cf;
1404 	dev->dv_cfdriver = cd;
1405 	dev->dv_cfattach = ca;
1406 	dev->dv_activity_count = 0;
1407 	dev->dv_activity_handlers = NULL;
1408 	dev->dv_private = dev_private;
1409 	dev->dv_flags = ca->ca_flags;	/* inherit flags from class */
1410 
1411 	myunit = config_unit_alloc(dev, cd, cf);
1412 	if (myunit == -1) {
1413 		config_devfree(dev);
1414 		return NULL;
1415 	}
1416 
1417 	/* compute length of name and decimal expansion of unit number */
1418 	lname = strlen(cd->cd_name);
1419 	xunit = number(&num[sizeof(num)], myunit);
1420 	lunit = &num[sizeof(num)] - xunit;
1421 	if (lname + lunit > sizeof(dev->dv_xname))
1422 		panic("config_devalloc: device name too long");
1423 
1424 	dvl = device_getlock(dev);
1425 
1426 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
1427 	cv_init(&dvl->dvl_cv, "pmfsusp");
1428 
1429 	memcpy(dev->dv_xname, cd->cd_name, lname);
1430 	memcpy(dev->dv_xname + lname, xunit, lunit);
1431 	dev->dv_parent = parent;
1432 	if (parent != NULL)
1433 		dev->dv_depth = parent->dv_depth + 1;
1434 	else
1435 		dev->dv_depth = 0;
1436 	dev->dv_flags |= DVF_ACTIVE;	/* always initially active */
1437 	if (locs) {
1438 		KASSERT(parent); /* no locators at root */
1439 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
1440 		dev->dv_locators =
1441 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
1442 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
1443 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
1444 	}
1445 	dev->dv_properties = prop_dictionary_create();
1446 	KASSERT(dev->dv_properties != NULL);
1447 
1448 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
1449 	    "device-driver", dev->dv_cfdriver->cd_name);
1450 	prop_dictionary_set_uint16(dev->dv_properties,
1451 	    "device-unit", dev->dv_unit);
1452 	if (parent != NULL) {
1453 		prop_dictionary_set_cstring(dev->dv_properties,
1454 		    "device-parent", device_xname(parent));
1455 	}
1456 
1457 	if (dev->dv_cfdriver->cd_attrs != NULL)
1458 		config_add_attrib_dict(dev);
1459 
1460 	return dev;
1461 }
1462 
1463 /*
1464  * Create an array of device attach attributes and add it
1465  * to the device's dv_properties dictionary.
1466  *
1467  * <key>interface-attributes</key>
1468  * <array>
1469  *    <dict>
1470  *       <key>attribute-name</key>
1471  *       <string>foo</string>
1472  *       <key>locators</key>
1473  *       <array>
1474  *          <dict>
1475  *             <key>loc-name</key>
1476  *             <string>foo-loc1</string>
1477  *          </dict>
1478  *          <dict>
1479  *             <key>loc-name</key>
1480  *             <string>foo-loc2</string>
1481  *             <key>default</key>
1482  *             <string>foo-loc2-default</string>
1483  *          </dict>
1484  *          ...
1485  *       </array>
1486  *    </dict>
1487  *    ...
1488  * </array>
1489  */
1490 
1491 static void
1492 config_add_attrib_dict(device_t dev)
1493 {
1494 	int i, j;
1495 	const struct cfiattrdata *ci;
1496 	prop_dictionary_t attr_dict, loc_dict;
1497 	prop_array_t attr_array, loc_array;
1498 
1499 	if ((attr_array = prop_array_create()) == NULL)
1500 		return;
1501 
1502 	for (i = 0; ; i++) {
1503 		if ((ci = dev->dv_cfdriver->cd_attrs[i]) == NULL)
1504 			break;
1505 		if ((attr_dict = prop_dictionary_create()) == NULL)
1506 			break;
1507 		prop_dictionary_set_cstring_nocopy(attr_dict, "attribute-name",
1508 		    ci->ci_name);
1509 
1510 		/* Create an array of the locator names and defaults */
1511 
1512 		if (ci->ci_loclen != 0 &&
1513 		    (loc_array = prop_array_create()) != NULL) {
1514 			for (j = 0; j < ci->ci_loclen; j++) {
1515 				loc_dict = prop_dictionary_create();
1516 				if (loc_dict == NULL)
1517 					continue;
1518 				prop_dictionary_set_cstring_nocopy(loc_dict,
1519 				    "loc-name", ci->ci_locdesc[j].cld_name);
1520 				if (ci->ci_locdesc[j].cld_defaultstr != NULL)
1521 					prop_dictionary_set_cstring_nocopy(
1522 					    loc_dict, "default",
1523 					    ci->ci_locdesc[j].cld_defaultstr);
1524 				prop_array_set(loc_array, j, loc_dict);
1525 				prop_object_release(loc_dict);
1526 			}
1527 			prop_dictionary_set_and_rel(attr_dict, "locators",
1528 			    loc_array);
1529 		}
1530 		prop_array_add(attr_array, attr_dict);
1531 		prop_object_release(attr_dict);
1532 	}
1533 	if (i == 0)
1534 		prop_object_release(attr_array);
1535 	else
1536 		prop_dictionary_set_and_rel(dev->dv_properties,
1537 		    "interface-attributes", attr_array);
1538 
1539 	return;
1540 }
1541 
1542 /*
1543  * Attach a found device.
1544  */
1545 device_t
1546 config_attach_loc(device_t parent, cfdata_t cf,
1547 	const int *locs, void *aux, cfprint_t print)
1548 {
1549 	device_t dev;
1550 	struct cftable *ct;
1551 	const char *drvname;
1552 
1553 	dev = config_devalloc(parent, cf, locs);
1554 	if (!dev)
1555 		panic("config_attach: allocation of device softc failed");
1556 
1557 	/* XXX redundant - see below? */
1558 	if (cf->cf_fstate != FSTATE_STAR) {
1559 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1560 		cf->cf_fstate = FSTATE_FOUND;
1561 	}
1562 
1563 	config_devlink(dev);
1564 
1565 	if (config_do_twiddle && cold)
1566 		twiddle();
1567 	else
1568 		aprint_naive("Found ");
1569 	/*
1570 	 * We want the next two printfs for normal, verbose, and quiet,
1571 	 * but not silent (in which case, we're twiddling, instead).
1572 	 */
1573 	if (parent == ROOT) {
1574 		aprint_naive("%s (root)", device_xname(dev));
1575 		aprint_normal("%s (root)", device_xname(dev));
1576 	} else {
1577 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
1578 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
1579 		if (print)
1580 			(void) (*print)(aux, NULL);
1581 	}
1582 
1583 	/*
1584 	 * Before attaching, clobber any unfound devices that are
1585 	 * otherwise identical.
1586 	 * XXX code above is redundant?
1587 	 */
1588 	drvname = dev->dv_cfdriver->cd_name;
1589 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1590 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1591 			if (STREQ(cf->cf_name, drvname) &&
1592 			    cf->cf_unit == dev->dv_unit) {
1593 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1594 					cf->cf_fstate = FSTATE_FOUND;
1595 			}
1596 		}
1597 	}
1598 	device_register(dev, aux);
1599 
1600 	/* Let userland know */
1601 	devmon_report_device(dev, true);
1602 
1603 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1604 
1605 	if (!device_pmf_is_registered(dev))
1606 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1607 
1608 	config_process_deferred(&deferred_config_queue, dev);
1609 
1610 	device_register_post_config(dev, aux);
1611 	return dev;
1612 }
1613 
1614 device_t
1615 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1616 {
1617 
1618 	return config_attach_loc(parent, cf, NULL, aux, print);
1619 }
1620 
1621 /*
1622  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1623  * way are silently inserted into the device tree, and their children
1624  * attached.
1625  *
1626  * Note that because pseudo-devices are attached silently, any information
1627  * the attach routine wishes to print should be prefixed with the device
1628  * name by the attach routine.
1629  */
1630 device_t
1631 config_attach_pseudo(cfdata_t cf)
1632 {
1633 	device_t dev;
1634 
1635 	dev = config_devalloc(ROOT, cf, NULL);
1636 	if (!dev)
1637 		return NULL;
1638 
1639 	/* XXX mark busy in cfdata */
1640 
1641 	if (cf->cf_fstate != FSTATE_STAR) {
1642 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1643 		cf->cf_fstate = FSTATE_FOUND;
1644 	}
1645 
1646 	config_devlink(dev);
1647 
1648 #if 0	/* XXXJRT not yet */
1649 	device_register(dev, NULL);	/* like a root node */
1650 #endif
1651 
1652 	/* Let userland know */
1653 	devmon_report_device(dev, true);
1654 
1655 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1656 
1657 	config_process_deferred(&deferred_config_queue, dev);
1658 	return dev;
1659 }
1660 
1661 /*
1662  * Caller must hold alldevs_mtx.
1663  */
1664 static void
1665 config_collect_garbage(struct devicelist *garbage)
1666 {
1667 	device_t dv;
1668 
1669 	KASSERT(!cpu_intr_p());
1670 	KASSERT(!cpu_softintr_p());
1671 	KASSERT(mutex_owned(&alldevs_mtx));
1672 
1673 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
1674 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
1675 			if (dv->dv_del_gen != 0)
1676 				break;
1677 		}
1678 		if (dv == NULL) {
1679 			alldevs_garbage = false;
1680 			break;
1681 		}
1682 		config_devunlink(dv, garbage);
1683 	}
1684 	KASSERT(mutex_owned(&alldevs_mtx));
1685 }
1686 
1687 static void
1688 config_dump_garbage(struct devicelist *garbage)
1689 {
1690 	device_t dv;
1691 
1692 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
1693 		TAILQ_REMOVE(garbage, dv, dv_list);
1694 		config_devdelete(dv);
1695 	}
1696 }
1697 
1698 /*
1699  * Detach a device.  Optionally forced (e.g. because of hardware
1700  * removal) and quiet.  Returns zero if successful, non-zero
1701  * (an error code) otherwise.
1702  *
1703  * Note that this code wants to be run from a process context, so
1704  * that the detach can sleep to allow processes which have a device
1705  * open to run and unwind their stacks.
1706  */
1707 int
1708 config_detach(device_t dev, int flags)
1709 {
1710 	struct alldevs_foray af;
1711 	struct cftable *ct;
1712 	cfdata_t cf;
1713 	const struct cfattach *ca;
1714 	struct cfdriver *cd;
1715 #ifdef DIAGNOSTIC
1716 	device_t d;
1717 #endif
1718 	int rv = 0, s;
1719 
1720 #ifdef DIAGNOSTIC
1721 	cf = dev->dv_cfdata;
1722 	if (cf != NULL && cf->cf_fstate != FSTATE_FOUND &&
1723 	    cf->cf_fstate != FSTATE_STAR)
1724 		panic("config_detach: %s: bad device fstate %d",
1725 		    device_xname(dev), cf ? cf->cf_fstate : -1);
1726 #endif
1727 	cd = dev->dv_cfdriver;
1728 	KASSERT(cd != NULL);
1729 
1730 	ca = dev->dv_cfattach;
1731 	KASSERT(ca != NULL);
1732 
1733 	s = config_alldevs_lock();
1734 	if (dev->dv_del_gen != 0) {
1735 		config_alldevs_unlock(s);
1736 #ifdef DIAGNOSTIC
1737 		printf("%s: %s is already detached\n", __func__,
1738 		    device_xname(dev));
1739 #endif /* DIAGNOSTIC */
1740 		return ENOENT;
1741 	}
1742 	alldevs_nwrite++;
1743 	config_alldevs_unlock(s);
1744 
1745 	if (!detachall &&
1746 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
1747 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
1748 		rv = EOPNOTSUPP;
1749 	} else if (ca->ca_detach != NULL) {
1750 		rv = (*ca->ca_detach)(dev, flags);
1751 	} else
1752 		rv = EOPNOTSUPP;
1753 
1754 	/*
1755 	 * If it was not possible to detach the device, then we either
1756 	 * panic() (for the forced but failed case), or return an error.
1757 	 *
1758 	 * If it was possible to detach the device, ensure that the
1759 	 * device is deactivated.
1760 	 */
1761 	if (rv == 0)
1762 		dev->dv_flags &= ~DVF_ACTIVE;
1763 	else if ((flags & DETACH_FORCE) == 0)
1764 		goto out;
1765 	else {
1766 		panic("config_detach: forced detach of %s failed (%d)",
1767 		    device_xname(dev), rv);
1768 	}
1769 
1770 	/*
1771 	 * The device has now been successfully detached.
1772 	 */
1773 
1774 	/* Let userland know */
1775 	devmon_report_device(dev, false);
1776 
1777 #ifdef DIAGNOSTIC
1778 	/*
1779 	 * Sanity: If you're successfully detached, you should have no
1780 	 * children.  (Note that because children must be attached
1781 	 * after parents, we only need to search the latter part of
1782 	 * the list.)
1783 	 */
1784 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1785 	    d = TAILQ_NEXT(d, dv_list)) {
1786 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
1787 			printf("config_detach: detached device %s"
1788 			    " has children %s\n", device_xname(dev), device_xname(d));
1789 			panic("config_detach");
1790 		}
1791 	}
1792 #endif
1793 
1794 	/* notify the parent that the child is gone */
1795 	if (dev->dv_parent) {
1796 		device_t p = dev->dv_parent;
1797 		if (p->dv_cfattach->ca_childdetached)
1798 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1799 	}
1800 
1801 	/*
1802 	 * Mark cfdata to show that the unit can be reused, if possible.
1803 	 */
1804 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1805 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1806 			if (STREQ(cf->cf_name, cd->cd_name)) {
1807 				if (cf->cf_fstate == FSTATE_FOUND &&
1808 				    cf->cf_unit == dev->dv_unit)
1809 					cf->cf_fstate = FSTATE_NOTFOUND;
1810 			}
1811 		}
1812 	}
1813 
1814 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1815 		aprint_normal_dev(dev, "detached\n");
1816 
1817 out:
1818 	config_alldevs_enter(&af);
1819 	KASSERT(alldevs_nwrite != 0);
1820 	--alldevs_nwrite;
1821 	if (rv == 0 && dev->dv_del_gen == 0) {
1822 		if (alldevs_nwrite == 0 && alldevs_nread == 0)
1823 			config_devunlink(dev, &af.af_garbage);
1824 		else {
1825 			dev->dv_del_gen = alldevs_gen;
1826 			alldevs_garbage = true;
1827 		}
1828 	}
1829 	config_alldevs_exit(&af);
1830 
1831 	return rv;
1832 }
1833 
1834 int
1835 config_detach_children(device_t parent, int flags)
1836 {
1837 	device_t dv;
1838 	deviter_t di;
1839 	int error = 0;
1840 
1841 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1842 	     dv = deviter_next(&di)) {
1843 		if (device_parent(dv) != parent)
1844 			continue;
1845 		if ((error = config_detach(dv, flags)) != 0)
1846 			break;
1847 	}
1848 	deviter_release(&di);
1849 	return error;
1850 }
1851 
1852 device_t
1853 shutdown_first(struct shutdown_state *s)
1854 {
1855 	if (!s->initialized) {
1856 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
1857 		s->initialized = true;
1858 	}
1859 	return shutdown_next(s);
1860 }
1861 
1862 device_t
1863 shutdown_next(struct shutdown_state *s)
1864 {
1865 	device_t dv;
1866 
1867 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
1868 		;
1869 
1870 	if (dv == NULL)
1871 		s->initialized = false;
1872 
1873 	return dv;
1874 }
1875 
1876 bool
1877 config_detach_all(int how)
1878 {
1879 	static struct shutdown_state s;
1880 	device_t curdev;
1881 	bool progress = false;
1882 
1883 	if ((how & RB_NOSYNC) != 0)
1884 		return false;
1885 
1886 	for (curdev = shutdown_first(&s); curdev != NULL;
1887 	     curdev = shutdown_next(&s)) {
1888 		aprint_debug(" detaching %s, ", device_xname(curdev));
1889 		if (config_detach(curdev, DETACH_SHUTDOWN) == 0) {
1890 			progress = true;
1891 			aprint_debug("success.");
1892 		} else
1893 			aprint_debug("failed.");
1894 	}
1895 	return progress;
1896 }
1897 
1898 static bool
1899 device_is_ancestor_of(device_t ancestor, device_t descendant)
1900 {
1901 	device_t dv;
1902 
1903 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
1904 		if (device_parent(dv) == ancestor)
1905 			return true;
1906 	}
1907 	return false;
1908 }
1909 
1910 int
1911 config_deactivate(device_t dev)
1912 {
1913 	deviter_t di;
1914 	const struct cfattach *ca;
1915 	device_t descendant;
1916 	int s, rv = 0, oflags;
1917 
1918 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
1919 	     descendant != NULL;
1920 	     descendant = deviter_next(&di)) {
1921 		if (dev != descendant &&
1922 		    !device_is_ancestor_of(dev, descendant))
1923 			continue;
1924 
1925 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
1926 			continue;
1927 
1928 		ca = descendant->dv_cfattach;
1929 		oflags = descendant->dv_flags;
1930 
1931 		descendant->dv_flags &= ~DVF_ACTIVE;
1932 		if (ca->ca_activate == NULL)
1933 			continue;
1934 		s = splhigh();
1935 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
1936 		splx(s);
1937 		if (rv != 0)
1938 			descendant->dv_flags = oflags;
1939 	}
1940 	deviter_release(&di);
1941 	return rv;
1942 }
1943 
1944 /*
1945  * Defer the configuration of the specified device until all
1946  * of its parent's devices have been attached.
1947  */
1948 void
1949 config_defer(device_t dev, void (*func)(device_t))
1950 {
1951 	struct deferred_config *dc;
1952 
1953 	if (dev->dv_parent == NULL)
1954 		panic("config_defer: can't defer config of a root device");
1955 
1956 #ifdef DIAGNOSTIC
1957 	TAILQ_FOREACH(dc, &deferred_config_queue, dc_queue) {
1958 		if (dc->dc_dev == dev)
1959 			panic("config_defer: deferred twice");
1960 	}
1961 #endif
1962 
1963 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1964 	if (dc == NULL)
1965 		panic("config_defer: unable to allocate callback");
1966 
1967 	dc->dc_dev = dev;
1968 	dc->dc_func = func;
1969 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1970 	config_pending_incr(dev);
1971 }
1972 
1973 /*
1974  * Defer some autoconfiguration for a device until after interrupts
1975  * are enabled.
1976  */
1977 void
1978 config_interrupts(device_t dev, void (*func)(device_t))
1979 {
1980 	struct deferred_config *dc;
1981 
1982 	/*
1983 	 * If interrupts are enabled, callback now.
1984 	 */
1985 	if (cold == 0) {
1986 		(*func)(dev);
1987 		return;
1988 	}
1989 
1990 #ifdef DIAGNOSTIC
1991 	TAILQ_FOREACH(dc, &interrupt_config_queue, dc_queue) {
1992 		if (dc->dc_dev == dev)
1993 			panic("config_interrupts: deferred twice");
1994 	}
1995 #endif
1996 
1997 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1998 	if (dc == NULL)
1999 		panic("config_interrupts: unable to allocate callback");
2000 
2001 	dc->dc_dev = dev;
2002 	dc->dc_func = func;
2003 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
2004 	config_pending_incr(dev);
2005 }
2006 
2007 /*
2008  * Defer some autoconfiguration for a device until after root file system
2009  * is mounted (to load firmware etc).
2010  */
2011 void
2012 config_mountroot(device_t dev, void (*func)(device_t))
2013 {
2014 	struct deferred_config *dc;
2015 
2016 	/*
2017 	 * If root file system is mounted, callback now.
2018 	 */
2019 	if (root_is_mounted) {
2020 		(*func)(dev);
2021 		return;
2022 	}
2023 
2024 #ifdef DIAGNOSTIC
2025 	TAILQ_FOREACH(dc, &mountroot_config_queue, dc_queue) {
2026 		if (dc->dc_dev == dev)
2027 			panic("%s: deferred twice", __func__);
2028 	}
2029 #endif
2030 
2031 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
2032 	if (dc == NULL)
2033 		panic("%s: unable to allocate callback", __func__);
2034 
2035 	dc->dc_dev = dev;
2036 	dc->dc_func = func;
2037 	TAILQ_INSERT_TAIL(&mountroot_config_queue, dc, dc_queue);
2038 }
2039 
2040 /*
2041  * Process a deferred configuration queue.
2042  */
2043 static void
2044 config_process_deferred(struct deferred_config_head *queue,
2045     device_t parent)
2046 {
2047 	struct deferred_config *dc, *ndc;
2048 
2049 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
2050 		ndc = TAILQ_NEXT(dc, dc_queue);
2051 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
2052 			TAILQ_REMOVE(queue, dc, dc_queue);
2053 			(*dc->dc_func)(dc->dc_dev);
2054 			config_pending_decr(dc->dc_dev);
2055 			kmem_free(dc, sizeof(*dc));
2056 		}
2057 	}
2058 }
2059 
2060 /*
2061  * Manipulate the config_pending semaphore.
2062  */
2063 void
2064 config_pending_incr(device_t dev)
2065 {
2066 
2067 	mutex_enter(&config_misc_lock);
2068 	config_pending++;
2069 #ifdef DEBUG_AUTOCONF
2070 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
2071 #endif
2072 	mutex_exit(&config_misc_lock);
2073 }
2074 
2075 void
2076 config_pending_decr(device_t dev)
2077 {
2078 
2079 #ifdef DIAGNOSTIC
2080 	if (config_pending == 0)
2081 		panic("config_pending_decr: config_pending == 0");
2082 #endif
2083 	mutex_enter(&config_misc_lock);
2084 	config_pending--;
2085 #ifdef DEBUG_AUTOCONF
2086 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
2087 #endif
2088 	if (config_pending == 0)
2089 		cv_broadcast(&config_misc_cv);
2090 	mutex_exit(&config_misc_lock);
2091 }
2092 
2093 /*
2094  * Register a "finalization" routine.  Finalization routines are
2095  * called iteratively once all real devices have been found during
2096  * autoconfiguration, for as long as any one finalizer has done
2097  * any work.
2098  */
2099 int
2100 config_finalize_register(device_t dev, int (*fn)(device_t))
2101 {
2102 	struct finalize_hook *f;
2103 
2104 	/*
2105 	 * If finalization has already been done, invoke the
2106 	 * callback function now.
2107 	 */
2108 	if (config_finalize_done) {
2109 		while ((*fn)(dev) != 0)
2110 			/* loop */ ;
2111 		return 0;
2112 	}
2113 
2114 	/* Ensure this isn't already on the list. */
2115 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
2116 		if (f->f_func == fn && f->f_dev == dev)
2117 			return EEXIST;
2118 	}
2119 
2120 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
2121 	f->f_func = fn;
2122 	f->f_dev = dev;
2123 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
2124 
2125 	return 0;
2126 }
2127 
2128 void
2129 config_finalize(void)
2130 {
2131 	struct finalize_hook *f;
2132 	struct pdevinit *pdev;
2133 	extern struct pdevinit pdevinit[];
2134 	int errcnt, rv;
2135 
2136 	/*
2137 	 * Now that device driver threads have been created, wait for
2138 	 * them to finish any deferred autoconfiguration.
2139 	 */
2140 	mutex_enter(&config_misc_lock);
2141 	while (config_pending != 0)
2142 		cv_wait(&config_misc_cv, &config_misc_lock);
2143 	mutex_exit(&config_misc_lock);
2144 
2145 	KERNEL_LOCK(1, NULL);
2146 
2147 	/* Attach pseudo-devices. */
2148 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
2149 		(*pdev->pdev_attach)(pdev->pdev_count);
2150 
2151 	/* Run the hooks until none of them does any work. */
2152 	do {
2153 		rv = 0;
2154 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
2155 			rv |= (*f->f_func)(f->f_dev);
2156 	} while (rv != 0);
2157 
2158 	config_finalize_done = 1;
2159 
2160 	/* Now free all the hooks. */
2161 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
2162 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
2163 		kmem_free(f, sizeof(*f));
2164 	}
2165 
2166 	KERNEL_UNLOCK_ONE(NULL);
2167 
2168 	errcnt = aprint_get_error_count();
2169 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
2170 	    (boothowto & AB_VERBOSE) == 0) {
2171 		mutex_enter(&config_misc_lock);
2172 		if (config_do_twiddle) {
2173 			config_do_twiddle = 0;
2174 			printf_nolog(" done.\n");
2175 		}
2176 		mutex_exit(&config_misc_lock);
2177 		if (errcnt != 0) {
2178 			printf("WARNING: %d error%s while detecting hardware; "
2179 			    "check system log.\n", errcnt,
2180 			    errcnt == 1 ? "" : "s");
2181 		}
2182 	}
2183 }
2184 
2185 void
2186 config_twiddle_init(void)
2187 {
2188 
2189 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
2190 		config_do_twiddle = 1;
2191 	}
2192 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
2193 }
2194 
2195 void
2196 config_twiddle_fn(void *cookie)
2197 {
2198 
2199 	mutex_enter(&config_misc_lock);
2200 	if (config_do_twiddle) {
2201 		twiddle();
2202 		callout_schedule(&config_twiddle_ch, mstohz(100));
2203 	}
2204 	mutex_exit(&config_misc_lock);
2205 }
2206 
2207 static int
2208 config_alldevs_lock(void)
2209 {
2210 	mutex_enter(&alldevs_mtx);
2211 	return 0;
2212 }
2213 
2214 static void
2215 config_alldevs_enter(struct alldevs_foray *af)
2216 {
2217 	TAILQ_INIT(&af->af_garbage);
2218 	af->af_s = config_alldevs_lock();
2219 	config_collect_garbage(&af->af_garbage);
2220 }
2221 
2222 static void
2223 config_alldevs_exit(struct alldevs_foray *af)
2224 {
2225 	config_alldevs_unlock(af->af_s);
2226 	config_dump_garbage(&af->af_garbage);
2227 }
2228 
2229 /*ARGSUSED*/
2230 static void
2231 config_alldevs_unlock(int s)
2232 {
2233 	mutex_exit(&alldevs_mtx);
2234 }
2235 
2236 /*
2237  * device_lookup:
2238  *
2239  *	Look up a device instance for a given driver.
2240  */
2241 device_t
2242 device_lookup(cfdriver_t cd, int unit)
2243 {
2244 	device_t dv;
2245 	int s;
2246 
2247 	s = config_alldevs_lock();
2248 	KASSERT(mutex_owned(&alldevs_mtx));
2249 	if (unit < 0 || unit >= cd->cd_ndevs)
2250 		dv = NULL;
2251 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
2252 		dv = NULL;
2253 	config_alldevs_unlock(s);
2254 
2255 	return dv;
2256 }
2257 
2258 /*
2259  * device_lookup_private:
2260  *
2261  *	Look up a softc instance for a given driver.
2262  */
2263 void *
2264 device_lookup_private(cfdriver_t cd, int unit)
2265 {
2266 
2267 	return device_private(device_lookup(cd, unit));
2268 }
2269 
2270 /*
2271  * device_find_by_xname:
2272  *
2273  *	Returns the device of the given name or NULL if it doesn't exist.
2274  */
2275 device_t
2276 device_find_by_xname(const char *name)
2277 {
2278 	device_t dv;
2279 	deviter_t di;
2280 
2281 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
2282 		if (strcmp(device_xname(dv), name) == 0)
2283 			break;
2284 	}
2285 	deviter_release(&di);
2286 
2287 	return dv;
2288 }
2289 
2290 /*
2291  * device_find_by_driver_unit:
2292  *
2293  *	Returns the device of the given driver name and unit or
2294  *	NULL if it doesn't exist.
2295  */
2296 device_t
2297 device_find_by_driver_unit(const char *name, int unit)
2298 {
2299 	struct cfdriver *cd;
2300 
2301 	if ((cd = config_cfdriver_lookup(name)) == NULL)
2302 		return NULL;
2303 	return device_lookup(cd, unit);
2304 }
2305 
2306 /*
2307  * Power management related functions.
2308  */
2309 
2310 bool
2311 device_pmf_is_registered(device_t dev)
2312 {
2313 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
2314 }
2315 
2316 bool
2317 device_pmf_driver_suspend(device_t dev, const pmf_qual_t *qual)
2318 {
2319 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2320 		return true;
2321 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2322 		return false;
2323 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2324 	    dev->dv_driver_suspend != NULL &&
2325 	    !(*dev->dv_driver_suspend)(dev, qual))
2326 		return false;
2327 
2328 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
2329 	return true;
2330 }
2331 
2332 bool
2333 device_pmf_driver_resume(device_t dev, const pmf_qual_t *qual)
2334 {
2335 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2336 		return true;
2337 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2338 		return false;
2339 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
2340 	    dev->dv_driver_resume != NULL &&
2341 	    !(*dev->dv_driver_resume)(dev, qual))
2342 		return false;
2343 
2344 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2345 	return true;
2346 }
2347 
2348 bool
2349 device_pmf_driver_shutdown(device_t dev, int how)
2350 {
2351 
2352 	if (*dev->dv_driver_shutdown != NULL &&
2353 	    !(*dev->dv_driver_shutdown)(dev, how))
2354 		return false;
2355 	return true;
2356 }
2357 
2358 bool
2359 device_pmf_driver_register(device_t dev,
2360     bool (*suspend)(device_t, const pmf_qual_t *),
2361     bool (*resume)(device_t, const pmf_qual_t *),
2362     bool (*shutdown)(device_t, int))
2363 {
2364 	dev->dv_driver_suspend = suspend;
2365 	dev->dv_driver_resume = resume;
2366 	dev->dv_driver_shutdown = shutdown;
2367 	dev->dv_flags |= DVF_POWER_HANDLERS;
2368 	return true;
2369 }
2370 
2371 static const char *
2372 curlwp_name(void)
2373 {
2374 	if (curlwp->l_name != NULL)
2375 		return curlwp->l_name;
2376 	else
2377 		return curlwp->l_proc->p_comm;
2378 }
2379 
2380 void
2381 device_pmf_driver_deregister(device_t dev)
2382 {
2383 	device_lock_t dvl = device_getlock(dev);
2384 
2385 	dev->dv_driver_suspend = NULL;
2386 	dev->dv_driver_resume = NULL;
2387 
2388 	mutex_enter(&dvl->dvl_mtx);
2389 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2390 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
2391 		/* Wake a thread that waits for the lock.  That
2392 		 * thread will fail to acquire the lock, and then
2393 		 * it will wake the next thread that waits for the
2394 		 * lock, or else it will wake us.
2395 		 */
2396 		cv_signal(&dvl->dvl_cv);
2397 		pmflock_debug(dev, __func__, __LINE__);
2398 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2399 		pmflock_debug(dev, __func__, __LINE__);
2400 	}
2401 	mutex_exit(&dvl->dvl_mtx);
2402 }
2403 
2404 bool
2405 device_pmf_driver_child_register(device_t dev)
2406 {
2407 	device_t parent = device_parent(dev);
2408 
2409 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2410 		return true;
2411 	return (*parent->dv_driver_child_register)(dev);
2412 }
2413 
2414 void
2415 device_pmf_driver_set_child_register(device_t dev,
2416     bool (*child_register)(device_t))
2417 {
2418 	dev->dv_driver_child_register = child_register;
2419 }
2420 
2421 static void
2422 pmflock_debug(device_t dev, const char *func, int line)
2423 {
2424 	device_lock_t dvl = device_getlock(dev);
2425 
2426 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n",
2427 	    func, line, curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait,
2428 	    dev->dv_flags);
2429 }
2430 
2431 static bool
2432 device_pmf_lock1(device_t dev)
2433 {
2434 	device_lock_t dvl = device_getlock(dev);
2435 
2436 	while (device_pmf_is_registered(dev) &&
2437 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
2438 		dvl->dvl_nwait++;
2439 		pmflock_debug(dev, __func__, __LINE__);
2440 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2441 		pmflock_debug(dev, __func__, __LINE__);
2442 		dvl->dvl_nwait--;
2443 	}
2444 	if (!device_pmf_is_registered(dev)) {
2445 		pmflock_debug(dev, __func__, __LINE__);
2446 		/* We could not acquire the lock, but some other thread may
2447 		 * wait for it, also.  Wake that thread.
2448 		 */
2449 		cv_signal(&dvl->dvl_cv);
2450 		return false;
2451 	}
2452 	dvl->dvl_nlock++;
2453 	dvl->dvl_holder = curlwp;
2454 	pmflock_debug(dev, __func__, __LINE__);
2455 	return true;
2456 }
2457 
2458 bool
2459 device_pmf_lock(device_t dev)
2460 {
2461 	bool rc;
2462 	device_lock_t dvl = device_getlock(dev);
2463 
2464 	mutex_enter(&dvl->dvl_mtx);
2465 	rc = device_pmf_lock1(dev);
2466 	mutex_exit(&dvl->dvl_mtx);
2467 
2468 	return rc;
2469 }
2470 
2471 void
2472 device_pmf_unlock(device_t dev)
2473 {
2474 	device_lock_t dvl = device_getlock(dev);
2475 
2476 	KASSERT(dvl->dvl_nlock > 0);
2477 	mutex_enter(&dvl->dvl_mtx);
2478 	if (--dvl->dvl_nlock == 0)
2479 		dvl->dvl_holder = NULL;
2480 	cv_signal(&dvl->dvl_cv);
2481 	pmflock_debug(dev, __func__, __LINE__);
2482 	mutex_exit(&dvl->dvl_mtx);
2483 }
2484 
2485 device_lock_t
2486 device_getlock(device_t dev)
2487 {
2488 	return &dev->dv_lock;
2489 }
2490 
2491 void *
2492 device_pmf_bus_private(device_t dev)
2493 {
2494 	return dev->dv_bus_private;
2495 }
2496 
2497 bool
2498 device_pmf_bus_suspend(device_t dev, const pmf_qual_t *qual)
2499 {
2500 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2501 		return true;
2502 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2503 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2504 		return false;
2505 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2506 	    dev->dv_bus_suspend != NULL &&
2507 	    !(*dev->dv_bus_suspend)(dev, qual))
2508 		return false;
2509 
2510 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2511 	return true;
2512 }
2513 
2514 bool
2515 device_pmf_bus_resume(device_t dev, const pmf_qual_t *qual)
2516 {
2517 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2518 		return true;
2519 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
2520 	    dev->dv_bus_resume != NULL &&
2521 	    !(*dev->dv_bus_resume)(dev, qual))
2522 		return false;
2523 
2524 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2525 	return true;
2526 }
2527 
2528 bool
2529 device_pmf_bus_shutdown(device_t dev, int how)
2530 {
2531 
2532 	if (*dev->dv_bus_shutdown != NULL &&
2533 	    !(*dev->dv_bus_shutdown)(dev, how))
2534 		return false;
2535 	return true;
2536 }
2537 
2538 void
2539 device_pmf_bus_register(device_t dev, void *priv,
2540     bool (*suspend)(device_t, const pmf_qual_t *),
2541     bool (*resume)(device_t, const pmf_qual_t *),
2542     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2543 {
2544 	dev->dv_bus_private = priv;
2545 	dev->dv_bus_resume = resume;
2546 	dev->dv_bus_suspend = suspend;
2547 	dev->dv_bus_shutdown = shutdown;
2548 	dev->dv_bus_deregister = deregister;
2549 }
2550 
2551 void
2552 device_pmf_bus_deregister(device_t dev)
2553 {
2554 	if (dev->dv_bus_deregister == NULL)
2555 		return;
2556 	(*dev->dv_bus_deregister)(dev);
2557 	dev->dv_bus_private = NULL;
2558 	dev->dv_bus_suspend = NULL;
2559 	dev->dv_bus_resume = NULL;
2560 	dev->dv_bus_deregister = NULL;
2561 }
2562 
2563 void *
2564 device_pmf_class_private(device_t dev)
2565 {
2566 	return dev->dv_class_private;
2567 }
2568 
2569 bool
2570 device_pmf_class_suspend(device_t dev, const pmf_qual_t *qual)
2571 {
2572 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2573 		return true;
2574 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2575 	    dev->dv_class_suspend != NULL &&
2576 	    !(*dev->dv_class_suspend)(dev, qual))
2577 		return false;
2578 
2579 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2580 	return true;
2581 }
2582 
2583 bool
2584 device_pmf_class_resume(device_t dev, const pmf_qual_t *qual)
2585 {
2586 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2587 		return true;
2588 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2589 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2590 		return false;
2591 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
2592 	    dev->dv_class_resume != NULL &&
2593 	    !(*dev->dv_class_resume)(dev, qual))
2594 		return false;
2595 
2596 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2597 	return true;
2598 }
2599 
2600 void
2601 device_pmf_class_register(device_t dev, void *priv,
2602     bool (*suspend)(device_t, const pmf_qual_t *),
2603     bool (*resume)(device_t, const pmf_qual_t *),
2604     void (*deregister)(device_t))
2605 {
2606 	dev->dv_class_private = priv;
2607 	dev->dv_class_suspend = suspend;
2608 	dev->dv_class_resume = resume;
2609 	dev->dv_class_deregister = deregister;
2610 }
2611 
2612 void
2613 device_pmf_class_deregister(device_t dev)
2614 {
2615 	if (dev->dv_class_deregister == NULL)
2616 		return;
2617 	(*dev->dv_class_deregister)(dev);
2618 	dev->dv_class_private = NULL;
2619 	dev->dv_class_suspend = NULL;
2620 	dev->dv_class_resume = NULL;
2621 	dev->dv_class_deregister = NULL;
2622 }
2623 
2624 bool
2625 device_active(device_t dev, devactive_t type)
2626 {
2627 	size_t i;
2628 
2629 	if (dev->dv_activity_count == 0)
2630 		return false;
2631 
2632 	for (i = 0; i < dev->dv_activity_count; ++i) {
2633 		if (dev->dv_activity_handlers[i] == NULL)
2634 			break;
2635 		(*dev->dv_activity_handlers[i])(dev, type);
2636 	}
2637 
2638 	return true;
2639 }
2640 
2641 bool
2642 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2643 {
2644 	void (**new_handlers)(device_t, devactive_t);
2645 	void (**old_handlers)(device_t, devactive_t);
2646 	size_t i, old_size, new_size;
2647 	int s;
2648 
2649 	old_handlers = dev->dv_activity_handlers;
2650 	old_size = dev->dv_activity_count;
2651 
2652 	for (i = 0; i < old_size; ++i) {
2653 		KASSERT(old_handlers[i] != handler);
2654 		if (old_handlers[i] == NULL) {
2655 			old_handlers[i] = handler;
2656 			return true;
2657 		}
2658 	}
2659 
2660 	new_size = old_size + 4;
2661 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
2662 
2663 	memcpy(new_handlers, old_handlers, sizeof(void *[old_size]));
2664 	new_handlers[old_size] = handler;
2665 	memset(new_handlers + old_size + 1, 0,
2666 	    sizeof(int [new_size - (old_size+1)]));
2667 
2668 	s = splhigh();
2669 	dev->dv_activity_count = new_size;
2670 	dev->dv_activity_handlers = new_handlers;
2671 	splx(s);
2672 
2673 	if (old_handlers != NULL)
2674 		kmem_free(old_handlers, sizeof(void * [old_size]));
2675 
2676 	return true;
2677 }
2678 
2679 void
2680 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2681 {
2682 	void (**old_handlers)(device_t, devactive_t);
2683 	size_t i, old_size;
2684 	int s;
2685 
2686 	old_handlers = dev->dv_activity_handlers;
2687 	old_size = dev->dv_activity_count;
2688 
2689 	for (i = 0; i < old_size; ++i) {
2690 		if (old_handlers[i] == handler)
2691 			break;
2692 		if (old_handlers[i] == NULL)
2693 			return; /* XXX panic? */
2694 	}
2695 
2696 	if (i == old_size)
2697 		return; /* XXX panic? */
2698 
2699 	for (; i < old_size - 1; ++i) {
2700 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
2701 			continue;
2702 
2703 		if (i == 0) {
2704 			s = splhigh();
2705 			dev->dv_activity_count = 0;
2706 			dev->dv_activity_handlers = NULL;
2707 			splx(s);
2708 			kmem_free(old_handlers, sizeof(void *[old_size]));
2709 		}
2710 		return;
2711 	}
2712 	old_handlers[i] = NULL;
2713 }
2714 
2715 /* Return true iff the device_t `dev' exists at generation `gen'. */
2716 static bool
2717 device_exists_at(device_t dv, devgen_t gen)
2718 {
2719 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
2720 	    dv->dv_add_gen <= gen;
2721 }
2722 
2723 static bool
2724 deviter_visits(const deviter_t *di, device_t dv)
2725 {
2726 	return device_exists_at(dv, di->di_gen);
2727 }
2728 
2729 /*
2730  * Device Iteration
2731  *
2732  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2733  *     each device_t's in the device tree.
2734  *
2735  * deviter_init(di, flags): initialize the device iterator `di'
2736  *     to "walk" the device tree.  deviter_next(di) will return
2737  *     the first device_t in the device tree, or NULL if there are
2738  *     no devices.
2739  *
2740  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2741  *     caller intends to modify the device tree by calling
2742  *     config_detach(9) on devices in the order that the iterator
2743  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2744  *     nearest the "root" of the device tree to be returned, first;
2745  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2746  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2747  *     indicating both that deviter_init() should not respect any
2748  *     locks on the device tree, and that deviter_next(di) may run
2749  *     in more than one LWP before the walk has finished.
2750  *
2751  *     Only one DEVITER_F_RW iterator may be in the device tree at
2752  *     once.
2753  *
2754  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2755  *
2756  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2757  *     DEVITER_F_LEAVES_FIRST are used in combination.
2758  *
2759  * deviter_first(di, flags): initialize the device iterator `di'
2760  *     and return the first device_t in the device tree, or NULL
2761  *     if there are no devices.  The statement
2762  *
2763  *         dv = deviter_first(di);
2764  *
2765  *     is shorthand for
2766  *
2767  *         deviter_init(di);
2768  *         dv = deviter_next(di);
2769  *
2770  * deviter_next(di): return the next device_t in the device tree,
2771  *     or NULL if there are no more devices.  deviter_next(di)
2772  *     is undefined if `di' was not initialized with deviter_init() or
2773  *     deviter_first().
2774  *
2775  * deviter_release(di): stops iteration (subsequent calls to
2776  *     deviter_next() will return NULL), releases any locks and
2777  *     resources held by the device iterator.
2778  *
2779  * Device iteration does not return device_t's in any particular
2780  * order.  An iterator will never return the same device_t twice.
2781  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2782  * is called repeatedly on the same `di', it will eventually return
2783  * NULL.  It is ok to attach/detach devices during device iteration.
2784  */
2785 void
2786 deviter_init(deviter_t *di, deviter_flags_t flags)
2787 {
2788 	device_t dv;
2789 	int s;
2790 
2791 	memset(di, 0, sizeof(*di));
2792 
2793 	s = config_alldevs_lock();
2794 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
2795 		flags |= DEVITER_F_RW;
2796 
2797 	if ((flags & DEVITER_F_RW) != 0)
2798 		alldevs_nwrite++;
2799 	else
2800 		alldevs_nread++;
2801 	di->di_gen = alldevs_gen++;
2802 	config_alldevs_unlock(s);
2803 
2804 	di->di_flags = flags;
2805 
2806 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2807 	case DEVITER_F_LEAVES_FIRST:
2808 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2809 			if (!deviter_visits(di, dv))
2810 				continue;
2811 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2812 		}
2813 		break;
2814 	case DEVITER_F_ROOT_FIRST:
2815 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
2816 			if (!deviter_visits(di, dv))
2817 				continue;
2818 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2819 		}
2820 		break;
2821 	default:
2822 		break;
2823 	}
2824 
2825 	deviter_reinit(di);
2826 }
2827 
2828 static void
2829 deviter_reinit(deviter_t *di)
2830 {
2831 	if ((di->di_flags & DEVITER_F_RW) != 0)
2832 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2833 	else
2834 		di->di_prev = TAILQ_FIRST(&alldevs);
2835 }
2836 
2837 device_t
2838 deviter_first(deviter_t *di, deviter_flags_t flags)
2839 {
2840 	deviter_init(di, flags);
2841 	return deviter_next(di);
2842 }
2843 
2844 static device_t
2845 deviter_next2(deviter_t *di)
2846 {
2847 	device_t dv;
2848 
2849 	dv = di->di_prev;
2850 
2851 	if (dv == NULL)
2852 		return NULL;
2853 
2854 	if ((di->di_flags & DEVITER_F_RW) != 0)
2855 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2856 	else
2857 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2858 
2859 	return dv;
2860 }
2861 
2862 static device_t
2863 deviter_next1(deviter_t *di)
2864 {
2865 	device_t dv;
2866 
2867 	do {
2868 		dv = deviter_next2(di);
2869 	} while (dv != NULL && !deviter_visits(di, dv));
2870 
2871 	return dv;
2872 }
2873 
2874 device_t
2875 deviter_next(deviter_t *di)
2876 {
2877 	device_t dv = NULL;
2878 
2879 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2880 	case 0:
2881 		return deviter_next1(di);
2882 	case DEVITER_F_LEAVES_FIRST:
2883 		while (di->di_curdepth >= 0) {
2884 			if ((dv = deviter_next1(di)) == NULL) {
2885 				di->di_curdepth--;
2886 				deviter_reinit(di);
2887 			} else if (dv->dv_depth == di->di_curdepth)
2888 				break;
2889 		}
2890 		return dv;
2891 	case DEVITER_F_ROOT_FIRST:
2892 		while (di->di_curdepth <= di->di_maxdepth) {
2893 			if ((dv = deviter_next1(di)) == NULL) {
2894 				di->di_curdepth++;
2895 				deviter_reinit(di);
2896 			} else if (dv->dv_depth == di->di_curdepth)
2897 				break;
2898 		}
2899 		return dv;
2900 	default:
2901 		return NULL;
2902 	}
2903 }
2904 
2905 void
2906 deviter_release(deviter_t *di)
2907 {
2908 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2909 	int s;
2910 
2911 	s = config_alldevs_lock();
2912 	if (rw)
2913 		--alldevs_nwrite;
2914 	else
2915 		--alldevs_nread;
2916 	/* XXX wake a garbage-collection thread */
2917 	config_alldevs_unlock(s);
2918 }
2919 
2920 const char *
2921 cfdata_ifattr(const struct cfdata *cf)
2922 {
2923 	return cf->cf_pspec->cfp_iattr;
2924 }
2925 
2926 bool
2927 ifattr_match(const char *snull, const char *t)
2928 {
2929 	return (snull == NULL) || strcmp(snull, t) == 0;
2930 }
2931 
2932 void
2933 null_childdetached(device_t self, device_t child)
2934 {
2935 	/* do nothing */
2936 }
2937 
2938 static void
2939 sysctl_detach_setup(struct sysctllog **clog)
2940 {
2941 
2942 	sysctl_createv(clog, 0, NULL, NULL,
2943 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
2944 		CTLTYPE_BOOL, "detachall",
2945 		SYSCTL_DESCR("Detach all devices at shutdown"),
2946 		NULL, 0, &detachall, 0,
2947 		CTL_KERN, CTL_CREATE, CTL_EOL);
2948 }
2949