xref: /netbsd-src/sys/kern/subr_autoconf.c (revision e6d6e05cb173f30287ab619b21120b27baa66ad6)
1 /* $NetBSD: subr_autoconf.c,v 1.137 2008/03/05 15:37:55 dyoung Exp $ */
2 
3 /*
4  * Copyright (c) 1996, 2000 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.NetBSD.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )--
35  */
36 
37 /*
38  * Copyright (c) 1992, 1993
39  *	The Regents of the University of California.  All rights reserved.
40  *
41  * This software was developed by the Computer Systems Engineering group
42  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
43  * contributed to Berkeley.
44  *
45  * All advertising materials mentioning features or use of this software
46  * must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Lawrence Berkeley Laboratories.
49  *
50  * Redistribution and use in source and binary forms, with or without
51  * modification, are permitted provided that the following conditions
52  * are met:
53  * 1. Redistributions of source code must retain the above copyright
54  *    notice, this list of conditions and the following disclaimer.
55  * 2. Redistributions in binary form must reproduce the above copyright
56  *    notice, this list of conditions and the following disclaimer in the
57  *    documentation and/or other materials provided with the distribution.
58  * 3. Neither the name of the University nor the names of its contributors
59  *    may be used to endorse or promote products derived from this software
60  *    without specific prior written permission.
61  *
62  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
63  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
64  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
65  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
66  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
67  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
68  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
69  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
70  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
71  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72  * SUCH DAMAGE.
73  *
74  * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp  (LBL)
75  *
76  *	@(#)subr_autoconf.c	8.3 (Berkeley) 5/17/94
77  */
78 
79 #include <sys/cdefs.h>
80 __KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.137 2008/03/05 15:37:55 dyoung Exp $");
81 
82 #include "opt_multiprocessor.h"
83 #include "opt_ddb.h"
84 
85 #include <sys/param.h>
86 #include <sys/device.h>
87 #include <sys/disklabel.h>
88 #include <sys/conf.h>
89 #include <sys/kauth.h>
90 #include <sys/malloc.h>
91 #include <sys/systm.h>
92 #include <sys/kernel.h>
93 #include <sys/errno.h>
94 #include <sys/proc.h>
95 #include <sys/reboot.h>
96 
97 #include <sys/buf.h>
98 #include <sys/dirent.h>
99 #include <sys/vnode.h>
100 #include <sys/mount.h>
101 #include <sys/namei.h>
102 #include <sys/unistd.h>
103 #include <sys/fcntl.h>
104 #include <sys/lockf.h>
105 #include <sys/callout.h>
106 #include <sys/mutex.h>
107 #include <sys/condvar.h>
108 
109 #include <sys/disk.h>
110 
111 #include <machine/limits.h>
112 
113 #include "opt_userconf.h"
114 #ifdef USERCONF
115 #include <sys/userconf.h>
116 #endif
117 
118 #ifdef __i386__
119 #include "opt_splash.h"
120 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
121 #include <dev/splash/splash.h>
122 extern struct splash_progress *splash_progress_state;
123 #endif
124 #endif
125 
126 /*
127  * Autoconfiguration subroutines.
128  */
129 
130 /*
131  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
132  * devices and drivers are found via these tables.
133  */
134 extern struct cfdata cfdata[];
135 extern const short cfroots[];
136 
137 /*
138  * List of all cfdriver structures.  We use this to detect duplicates
139  * when other cfdrivers are loaded.
140  */
141 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
142 extern struct cfdriver * const cfdriver_list_initial[];
143 
144 /*
145  * Initial list of cfattach's.
146  */
147 extern const struct cfattachinit cfattachinit[];
148 
149 /*
150  * List of cfdata tables.  We always have one such list -- the one
151  * built statically when the kernel was configured.
152  */
153 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
154 static struct cftable initcftable;
155 
156 #define	ROOT ((device_t)NULL)
157 
158 struct matchinfo {
159 	cfsubmatch_t fn;
160 	struct	device *parent;
161 	const int *locs;
162 	void	*aux;
163 	struct	cfdata *match;
164 	int	pri;
165 };
166 
167 static char *number(char *, int);
168 static void mapply(struct matchinfo *, cfdata_t);
169 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
170 static void config_devdealloc(device_t);
171 static void config_makeroom(int, struct cfdriver *);
172 static void config_devlink(device_t);
173 static void config_devunlink(device_t);
174 
175 static device_t deviter_next1(deviter_t *);
176 static void deviter_reinit(deviter_t *);
177 
178 struct deferred_config {
179 	TAILQ_ENTRY(deferred_config) dc_queue;
180 	device_t dc_dev;
181 	void (*dc_func)(device_t);
182 };
183 
184 TAILQ_HEAD(deferred_config_head, deferred_config);
185 
186 struct deferred_config_head deferred_config_queue =
187 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
188 struct deferred_config_head interrupt_config_queue =
189 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
190 
191 static void config_process_deferred(struct deferred_config_head *, device_t);
192 
193 /* Hooks to finalize configuration once all real devices have been found. */
194 struct finalize_hook {
195 	TAILQ_ENTRY(finalize_hook) f_list;
196 	int (*f_func)(device_t);
197 	device_t f_dev;
198 };
199 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
200 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
201 static int config_finalize_done;
202 
203 /* list of all devices */
204 struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
205 kcondvar_t alldevs_cv;
206 kmutex_t alldevs_mtx;
207 static int alldevs_nread = 0;
208 static int alldevs_nwrite = 0;
209 static lwp_t *alldevs_writer = NULL;
210 
211 volatile int config_pending;		/* semaphore for mountroot */
212 
213 #define	STREQ(s1, s2)			\
214 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
215 
216 static int config_initialized;		/* config_init() has been called. */
217 
218 static int config_do_twiddle;
219 
220 struct vnode *
221 opendisk(struct device *dv)
222 {
223 	int bmajor, bminor;
224 	struct vnode *tmpvn;
225 	int error;
226 	dev_t dev;
227 
228 	/*
229 	 * Lookup major number for disk block device.
230 	 */
231 	bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
232 	if (bmajor == -1)
233 		return NULL;
234 
235 	bminor = minor(device_unit(dv));
236 	/*
237 	 * Fake a temporary vnode for the disk, open it, and read
238 	 * and hash the sectors.
239 	 */
240 	dev = device_is_a(dv, "dk") ? makedev(bmajor, bminor) :
241 	    MAKEDISKDEV(bmajor, bminor, RAW_PART);
242 	if (bdevvp(dev, &tmpvn))
243 		panic("%s: can't alloc vnode for %s", __func__,
244 		    device_xname(dv));
245 	error = VOP_OPEN(tmpvn, FREAD, NOCRED);
246 	if (error) {
247 #ifndef DEBUG
248 		/*
249 		 * Ignore errors caused by missing device, partition,
250 		 * or medium.
251 		 */
252 		if (error != ENXIO && error != ENODEV)
253 #endif
254 			printf("%s: can't open dev %s (%d)\n",
255 			    __func__, device_xname(dv), error);
256 		vput(tmpvn);
257 		return NULL;
258 	}
259 
260 	return tmpvn;
261 }
262 
263 int
264 config_handle_wedges(struct device *dv, int par)
265 {
266 	struct dkwedge_list wl;
267 	struct dkwedge_info *wi;
268 	struct vnode *vn;
269 	char diskname[16];
270 	int i, error;
271 
272 	if ((vn = opendisk(dv)) == NULL)
273 		return -1;
274 
275 	wl.dkwl_bufsize = sizeof(*wi) * 16;
276 	wl.dkwl_buf = wi = malloc(wl.dkwl_bufsize, M_TEMP, M_WAITOK);
277 
278 	error = VOP_IOCTL(vn, DIOCLWEDGES, &wl, FREAD, NOCRED);
279 	VOP_CLOSE(vn, FREAD, NOCRED);
280 	vput(vn);
281 	if (error) {
282 #ifdef DEBUG_WEDGE
283 		printf("%s: List wedges returned %d\n",
284 		    device_xname(dv), error);
285 #endif
286 		free(wi, M_TEMP);
287 		return -1;
288 	}
289 
290 #ifdef DEBUG_WEDGE
291 	printf("%s: Returned %u(%u) wedges\n", device_xname(dv),
292 	    wl.dkwl_nwedges, wl.dkwl_ncopied);
293 #endif
294 	snprintf(diskname, sizeof(diskname), "%s%c", device_xname(dv),
295 	    par + 'a');
296 
297 	for (i = 0; i < wl.dkwl_ncopied; i++) {
298 #ifdef DEBUG_WEDGE
299 		printf("%s: Looking for %s in %s\n",
300 		    device_xname(dv), diskname, wi[i].dkw_wname);
301 #endif
302 		if (strcmp(wi[i].dkw_wname, diskname) == 0)
303 			break;
304 	}
305 
306 	if (i == wl.dkwl_ncopied) {
307 #ifdef DEBUG_WEDGE
308 		printf("%s: Cannot find wedge with parent %s\n",
309 		    device_xname(dv), diskname);
310 #endif
311 		free(wi, M_TEMP);
312 		return -1;
313 	}
314 
315 #ifdef DEBUG_WEDGE
316 	printf("%s: Setting boot wedge %s (%s) at %llu %llu\n",
317 		device_xname(dv), wi[i].dkw_devname, wi[i].dkw_wname,
318 		(unsigned long long)wi[i].dkw_offset,
319 		(unsigned long long)wi[i].dkw_size);
320 #endif
321 	dkwedge_set_bootwedge(dv, wi[i].dkw_offset, wi[i].dkw_size);
322 	free(wi, M_TEMP);
323 	return 0;
324 }
325 
326 /*
327  * Initialize the autoconfiguration data structures.  Normally this
328  * is done by configure(), but some platforms need to do this very
329  * early (to e.g. initialize the console).
330  */
331 void
332 config_init(void)
333 {
334 	const struct cfattachinit *cfai;
335 	int i, j;
336 
337 	if (config_initialized)
338 		return;
339 
340 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_NONE);
341 	cv_init(&alldevs_cv, "alldevs");
342 
343 	/* allcfdrivers is statically initialized. */
344 	for (i = 0; cfdriver_list_initial[i] != NULL; i++) {
345 		if (config_cfdriver_attach(cfdriver_list_initial[i]) != 0)
346 			panic("configure: duplicate `%s' drivers",
347 			    cfdriver_list_initial[i]->cd_name);
348 	}
349 
350 	for (cfai = &cfattachinit[0]; cfai->cfai_name != NULL; cfai++) {
351 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
352 			if (config_cfattach_attach(cfai->cfai_name,
353 						   cfai->cfai_list[j]) != 0)
354 				panic("configure: duplicate `%s' attachment "
355 				    "of `%s' driver",
356 				    cfai->cfai_list[j]->ca_name,
357 				    cfai->cfai_name);
358 		}
359 	}
360 
361 	initcftable.ct_cfdata = cfdata;
362 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
363 
364 	config_initialized = 1;
365 }
366 
367 void
368 config_deferred(device_t dev)
369 {
370 	config_process_deferred(&deferred_config_queue, dev);
371 	config_process_deferred(&interrupt_config_queue, dev);
372 }
373 
374 /*
375  * Configure the system's hardware.
376  */
377 void
378 configure(void)
379 {
380 	int errcnt;
381 
382 	/* Initialize data structures. */
383 	config_init();
384 	pmf_init();
385 
386 #ifdef USERCONF
387 	if (boothowto & RB_USERCONF)
388 		user_config();
389 #endif
390 
391 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
392 		config_do_twiddle = 1;
393 		printf_nolog("Detecting hardware...");
394 	}
395 
396 	/*
397 	 * Do the machine-dependent portion of autoconfiguration.  This
398 	 * sets the configuration machinery here in motion by "finding"
399 	 * the root bus.  When this function returns, we expect interrupts
400 	 * to be enabled.
401 	 */
402 	cpu_configure();
403 
404 	/* Initialize callouts, part 2. */
405 	callout_startup2();
406 
407 	/*
408 	 * Now that we've found all the hardware, start the real time
409 	 * and statistics clocks.
410 	 */
411 	initclocks();
412 
413 	cold = 0;	/* clocks are running, we're warm now! */
414 
415 	/* Boot the secondary processors. */
416 	mp_online = true;
417 #if defined(MULTIPROCESSOR)
418 	cpu_boot_secondary_processors();
419 #endif
420 
421 	/*
422 	 * Now callback to finish configuration for devices which want
423 	 * to do this once interrupts are enabled.
424 	 */
425 	config_process_deferred(&interrupt_config_queue, NULL);
426 
427 	errcnt = aprint_get_error_count();
428 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
429 	    (boothowto & AB_VERBOSE) == 0) {
430 		if (config_do_twiddle) {
431 			config_do_twiddle = 0;
432 			printf_nolog("done.\n");
433 		}
434 		if (errcnt != 0) {
435 			printf("WARNING: %d error%s while detecting hardware; "
436 			    "check system log.\n", errcnt,
437 			    errcnt == 1 ? "" : "s");
438 		}
439 	}
440 }
441 
442 /*
443  * Add a cfdriver to the system.
444  */
445 int
446 config_cfdriver_attach(struct cfdriver *cd)
447 {
448 	struct cfdriver *lcd;
449 
450 	/* Make sure this driver isn't already in the system. */
451 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
452 		if (STREQ(lcd->cd_name, cd->cd_name))
453 			return (EEXIST);
454 	}
455 
456 	LIST_INIT(&cd->cd_attach);
457 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
458 
459 	return (0);
460 }
461 
462 /*
463  * Remove a cfdriver from the system.
464  */
465 int
466 config_cfdriver_detach(struct cfdriver *cd)
467 {
468 	int i;
469 
470 	/* Make sure there are no active instances. */
471 	for (i = 0; i < cd->cd_ndevs; i++) {
472 		if (cd->cd_devs[i] != NULL)
473 			return (EBUSY);
474 	}
475 
476 	/* ...and no attachments loaded. */
477 	if (LIST_EMPTY(&cd->cd_attach) == 0)
478 		return (EBUSY);
479 
480 	LIST_REMOVE(cd, cd_list);
481 
482 	KASSERT(cd->cd_devs == NULL);
483 
484 	return (0);
485 }
486 
487 /*
488  * Look up a cfdriver by name.
489  */
490 struct cfdriver *
491 config_cfdriver_lookup(const char *name)
492 {
493 	struct cfdriver *cd;
494 
495 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
496 		if (STREQ(cd->cd_name, name))
497 			return (cd);
498 	}
499 
500 	return (NULL);
501 }
502 
503 /*
504  * Add a cfattach to the specified driver.
505  */
506 int
507 config_cfattach_attach(const char *driver, struct cfattach *ca)
508 {
509 	struct cfattach *lca;
510 	struct cfdriver *cd;
511 
512 	cd = config_cfdriver_lookup(driver);
513 	if (cd == NULL)
514 		return (ESRCH);
515 
516 	/* Make sure this attachment isn't already on this driver. */
517 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
518 		if (STREQ(lca->ca_name, ca->ca_name))
519 			return (EEXIST);
520 	}
521 
522 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
523 
524 	return (0);
525 }
526 
527 /*
528  * Remove a cfattach from the specified driver.
529  */
530 int
531 config_cfattach_detach(const char *driver, struct cfattach *ca)
532 {
533 	struct cfdriver *cd;
534 	device_t dev;
535 	int i;
536 
537 	cd = config_cfdriver_lookup(driver);
538 	if (cd == NULL)
539 		return (ESRCH);
540 
541 	/* Make sure there are no active instances. */
542 	for (i = 0; i < cd->cd_ndevs; i++) {
543 		if ((dev = cd->cd_devs[i]) == NULL)
544 			continue;
545 		if (dev->dv_cfattach == ca)
546 			return (EBUSY);
547 	}
548 
549 	LIST_REMOVE(ca, ca_list);
550 
551 	return (0);
552 }
553 
554 /*
555  * Look up a cfattach by name.
556  */
557 static struct cfattach *
558 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
559 {
560 	struct cfattach *ca;
561 
562 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
563 		if (STREQ(ca->ca_name, atname))
564 			return (ca);
565 	}
566 
567 	return (NULL);
568 }
569 
570 /*
571  * Look up a cfattach by driver/attachment name.
572  */
573 struct cfattach *
574 config_cfattach_lookup(const char *name, const char *atname)
575 {
576 	struct cfdriver *cd;
577 
578 	cd = config_cfdriver_lookup(name);
579 	if (cd == NULL)
580 		return (NULL);
581 
582 	return (config_cfattach_lookup_cd(cd, atname));
583 }
584 
585 /*
586  * Apply the matching function and choose the best.  This is used
587  * a few times and we want to keep the code small.
588  */
589 static void
590 mapply(struct matchinfo *m, cfdata_t cf)
591 {
592 	int pri;
593 
594 	if (m->fn != NULL) {
595 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
596 	} else {
597 		pri = config_match(m->parent, cf, m->aux);
598 	}
599 	if (pri > m->pri) {
600 		m->match = cf;
601 		m->pri = pri;
602 	}
603 }
604 
605 int
606 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
607 {
608 	const struct cfiattrdata *ci;
609 	const struct cflocdesc *cl;
610 	int nlocs, i;
611 
612 	ci = cfiattr_lookup(cf->cf_pspec->cfp_iattr, parent->dv_cfdriver);
613 	KASSERT(ci);
614 	nlocs = ci->ci_loclen;
615 	for (i = 0; i < nlocs; i++) {
616 		cl = &ci->ci_locdesc[i];
617 		/* !cld_defaultstr means no default value */
618 		if ((!(cl->cld_defaultstr)
619 		     || (cf->cf_loc[i] != cl->cld_default))
620 		    && cf->cf_loc[i] != locs[i])
621 			return (0);
622 	}
623 
624 	return (config_match(parent, cf, aux));
625 }
626 
627 /*
628  * Helper function: check whether the driver supports the interface attribute
629  * and return its descriptor structure.
630  */
631 static const struct cfiattrdata *
632 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
633 {
634 	const struct cfiattrdata * const *cpp;
635 
636 	if (cd->cd_attrs == NULL)
637 		return (0);
638 
639 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
640 		if (STREQ((*cpp)->ci_name, ia)) {
641 			/* Match. */
642 			return (*cpp);
643 		}
644 	}
645 	return (0);
646 }
647 
648 /*
649  * Lookup an interface attribute description by name.
650  * If the driver is given, consider only its supported attributes.
651  */
652 const struct cfiattrdata *
653 cfiattr_lookup(const char *name, const struct cfdriver *cd)
654 {
655 	const struct cfdriver *d;
656 	const struct cfiattrdata *ia;
657 
658 	if (cd)
659 		return (cfdriver_get_iattr(cd, name));
660 
661 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
662 		ia = cfdriver_get_iattr(d, name);
663 		if (ia)
664 			return (ia);
665 	}
666 	return (0);
667 }
668 
669 /*
670  * Determine if `parent' is a potential parent for a device spec based
671  * on `cfp'.
672  */
673 static int
674 cfparent_match(const device_t parent, const struct cfparent *cfp)
675 {
676 	struct cfdriver *pcd;
677 
678 	/* We don't match root nodes here. */
679 	if (cfp == NULL)
680 		return (0);
681 
682 	pcd = parent->dv_cfdriver;
683 	KASSERT(pcd != NULL);
684 
685 	/*
686 	 * First, ensure this parent has the correct interface
687 	 * attribute.
688 	 */
689 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
690 		return (0);
691 
692 	/*
693 	 * If no specific parent device instance was specified (i.e.
694 	 * we're attaching to the attribute only), we're done!
695 	 */
696 	if (cfp->cfp_parent == NULL)
697 		return (1);
698 
699 	/*
700 	 * Check the parent device's name.
701 	 */
702 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
703 		return (0);	/* not the same parent */
704 
705 	/*
706 	 * Make sure the unit number matches.
707 	 */
708 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
709 	    cfp->cfp_unit == parent->dv_unit)
710 		return (1);
711 
712 	/* Unit numbers don't match. */
713 	return (0);
714 }
715 
716 /*
717  * Helper for config_cfdata_attach(): check all devices whether it could be
718  * parent any attachment in the config data table passed, and rescan.
719  */
720 static void
721 rescan_with_cfdata(const struct cfdata *cf)
722 {
723 	device_t d;
724 	const struct cfdata *cf1;
725 	deviter_t di;
726 
727 
728 	/*
729 	 * "alldevs" is likely longer than an LKM's cfdata, so make it
730 	 * the outer loop.
731 	 */
732 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
733 
734 		if (!(d->dv_cfattach->ca_rescan))
735 			continue;
736 
737 		for (cf1 = cf; cf1->cf_name; cf1++) {
738 
739 			if (!cfparent_match(d, cf1->cf_pspec))
740 				continue;
741 
742 			(*d->dv_cfattach->ca_rescan)(d,
743 				cf1->cf_pspec->cfp_iattr, cf1->cf_loc);
744 		}
745 	}
746 	deviter_release(&di);
747 }
748 
749 /*
750  * Attach a supplemental config data table and rescan potential
751  * parent devices if required.
752  */
753 int
754 config_cfdata_attach(cfdata_t cf, int scannow)
755 {
756 	struct cftable *ct;
757 
758 	ct = malloc(sizeof(struct cftable), M_DEVBUF, M_WAITOK);
759 	ct->ct_cfdata = cf;
760 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
761 
762 	if (scannow)
763 		rescan_with_cfdata(cf);
764 
765 	return (0);
766 }
767 
768 /*
769  * Helper for config_cfdata_detach: check whether a device is
770  * found through any attachment in the config data table.
771  */
772 static int
773 dev_in_cfdata(const struct device *d, const struct cfdata *cf)
774 {
775 	const struct cfdata *cf1;
776 
777 	for (cf1 = cf; cf1->cf_name; cf1++)
778 		if (d->dv_cfdata == cf1)
779 			return (1);
780 
781 	return (0);
782 }
783 
784 /*
785  * Detach a supplemental config data table. Detach all devices found
786  * through that table (and thus keeping references to it) before.
787  */
788 int
789 config_cfdata_detach(cfdata_t cf)
790 {
791 	device_t d;
792 	int error = 0;
793 	struct cftable *ct;
794 	deviter_t di;
795 
796 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
797 	     d = deviter_next(&di)) {
798 		if (!dev_in_cfdata(d, cf))
799 			continue;
800 		if ((error = config_detach(d, 0)) != 0)
801 			break;
802 	}
803 	deviter_release(&di);
804 	if (error) {
805 		aprint_error_dev(d, "unable to detach instance\n");
806 		return error;
807 	}
808 
809 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
810 		if (ct->ct_cfdata == cf) {
811 			TAILQ_REMOVE(&allcftables, ct, ct_list);
812 			free(ct, M_DEVBUF);
813 			return (0);
814 		}
815 	}
816 
817 	/* not found -- shouldn't happen */
818 	return (EINVAL);
819 }
820 
821 /*
822  * Invoke the "match" routine for a cfdata entry on behalf of
823  * an external caller, usually a "submatch" routine.
824  */
825 int
826 config_match(device_t parent, cfdata_t cf, void *aux)
827 {
828 	struct cfattach *ca;
829 
830 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
831 	if (ca == NULL) {
832 		/* No attachment for this entry, oh well. */
833 		return (0);
834 	}
835 
836 	return ((*ca->ca_match)(parent, cf, aux));
837 }
838 
839 /*
840  * Iterate over all potential children of some device, calling the given
841  * function (default being the child's match function) for each one.
842  * Nonzero returns are matches; the highest value returned is considered
843  * the best match.  Return the `found child' if we got a match, or NULL
844  * otherwise.  The `aux' pointer is simply passed on through.
845  *
846  * Note that this function is designed so that it can be used to apply
847  * an arbitrary function to all potential children (its return value
848  * can be ignored).
849  */
850 cfdata_t
851 config_search_loc(cfsubmatch_t fn, device_t parent,
852 		  const char *ifattr, const int *locs, void *aux)
853 {
854 	struct cftable *ct;
855 	cfdata_t cf;
856 	struct matchinfo m;
857 
858 	KASSERT(config_initialized);
859 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
860 
861 	m.fn = fn;
862 	m.parent = parent;
863 	m.locs = locs;
864 	m.aux = aux;
865 	m.match = NULL;
866 	m.pri = 0;
867 
868 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
869 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
870 
871 			/* We don't match root nodes here. */
872 			if (!cf->cf_pspec)
873 				continue;
874 
875 			/*
876 			 * Skip cf if no longer eligible, otherwise scan
877 			 * through parents for one matching `parent', and
878 			 * try match function.
879 			 */
880 			if (cf->cf_fstate == FSTATE_FOUND)
881 				continue;
882 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
883 			    cf->cf_fstate == FSTATE_DSTAR)
884 				continue;
885 
886 			/*
887 			 * If an interface attribute was specified,
888 			 * consider only children which attach to
889 			 * that attribute.
890 			 */
891 			if (ifattr && !STREQ(ifattr, cf->cf_pspec->cfp_iattr))
892 				continue;
893 
894 			if (cfparent_match(parent, cf->cf_pspec))
895 				mapply(&m, cf);
896 		}
897 	}
898 	return (m.match);
899 }
900 
901 cfdata_t
902 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
903     void *aux)
904 {
905 
906 	return (config_search_loc(fn, parent, ifattr, NULL, aux));
907 }
908 
909 /*
910  * Find the given root device.
911  * This is much like config_search, but there is no parent.
912  * Don't bother with multiple cfdata tables; the root node
913  * must always be in the initial table.
914  */
915 cfdata_t
916 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
917 {
918 	cfdata_t cf;
919 	const short *p;
920 	struct matchinfo m;
921 
922 	m.fn = fn;
923 	m.parent = ROOT;
924 	m.aux = aux;
925 	m.match = NULL;
926 	m.pri = 0;
927 	m.locs = 0;
928 	/*
929 	 * Look at root entries for matching name.  We do not bother
930 	 * with found-state here since only one root should ever be
931 	 * searched (and it must be done first).
932 	 */
933 	for (p = cfroots; *p >= 0; p++) {
934 		cf = &cfdata[*p];
935 		if (strcmp(cf->cf_name, rootname) == 0)
936 			mapply(&m, cf);
937 	}
938 	return (m.match);
939 }
940 
941 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
942 
943 /*
944  * The given `aux' argument describes a device that has been found
945  * on the given parent, but not necessarily configured.  Locate the
946  * configuration data for that device (using the submatch function
947  * provided, or using candidates' cd_match configuration driver
948  * functions) and attach it, and return true.  If the device was
949  * not configured, call the given `print' function and return 0.
950  */
951 device_t
952 config_found_sm_loc(device_t parent,
953 		const char *ifattr, const int *locs, void *aux,
954 		cfprint_t print, cfsubmatch_t submatch)
955 {
956 	cfdata_t cf;
957 
958 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
959 	if (splash_progress_state)
960 		splash_progress_update(splash_progress_state);
961 #endif
962 
963 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
964 		return(config_attach_loc(parent, cf, locs, aux, print));
965 	if (print) {
966 		if (config_do_twiddle)
967 			twiddle();
968 		aprint_normal("%s", msgs[(*print)(aux, parent->dv_xname)]);
969 	}
970 
971 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
972 	if (splash_progress_state)
973 		splash_progress_update(splash_progress_state);
974 #endif
975 
976 	return (NULL);
977 }
978 
979 device_t
980 config_found_ia(device_t parent, const char *ifattr, void *aux,
981     cfprint_t print)
982 {
983 
984 	return (config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL));
985 }
986 
987 device_t
988 config_found(device_t parent, void *aux, cfprint_t print)
989 {
990 
991 	return (config_found_sm_loc(parent, NULL, NULL, aux, print, NULL));
992 }
993 
994 /*
995  * As above, but for root devices.
996  */
997 device_t
998 config_rootfound(const char *rootname, void *aux)
999 {
1000 	cfdata_t cf;
1001 
1002 	if ((cf = config_rootsearch((cfsubmatch_t)NULL, rootname, aux)) != NULL)
1003 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
1004 	aprint_error("root device %s not configured\n", rootname);
1005 	return (NULL);
1006 }
1007 
1008 /* just like sprintf(buf, "%d") except that it works from the end */
1009 static char *
1010 number(char *ep, int n)
1011 {
1012 
1013 	*--ep = 0;
1014 	while (n >= 10) {
1015 		*--ep = (n % 10) + '0';
1016 		n /= 10;
1017 	}
1018 	*--ep = n + '0';
1019 	return (ep);
1020 }
1021 
1022 /*
1023  * Expand the size of the cd_devs array if necessary.
1024  */
1025 static void
1026 config_makeroom(int n, struct cfdriver *cd)
1027 {
1028 	int old, new;
1029 	void **nsp;
1030 
1031 	if (n < cd->cd_ndevs)
1032 		return;
1033 
1034 	/*
1035 	 * Need to expand the array.
1036 	 */
1037 	old = cd->cd_ndevs;
1038 	if (old == 0)
1039 		new = 4;
1040 	else
1041 		new = old * 2;
1042 	while (new <= n)
1043 		new *= 2;
1044 	cd->cd_ndevs = new;
1045 	nsp = malloc(new * sizeof(void *), M_DEVBUF,
1046 	    cold ? M_NOWAIT : M_WAITOK);
1047 	if (nsp == NULL)
1048 		panic("config_attach: %sing dev array",
1049 		    old != 0 ? "expand" : "creat");
1050 	memset(nsp + old, 0, (new - old) * sizeof(void *));
1051 	if (old != 0) {
1052 		memcpy(nsp, cd->cd_devs, old * sizeof(void *));
1053 		free(cd->cd_devs, M_DEVBUF);
1054 	}
1055 	cd->cd_devs = nsp;
1056 }
1057 
1058 static void
1059 config_devlink(device_t dev)
1060 {
1061 	struct cfdriver *cd = dev->dv_cfdriver;
1062 
1063 	/* put this device in the devices array */
1064 	config_makeroom(dev->dv_unit, cd);
1065 	if (cd->cd_devs[dev->dv_unit])
1066 		panic("config_attach: duplicate %s", dev->dv_xname);
1067 	cd->cd_devs[dev->dv_unit] = dev;
1068 
1069 	/* It is safe to add a device to the tail of the list while
1070 	 * readers are in the list, but not while a writer is in
1071 	 * the list.  Wait for any writer to complete.
1072 	 */
1073 	mutex_enter(&alldevs_mtx);
1074 	while (alldevs_nwrite != 0 && alldevs_writer != curlwp)
1075 		cv_wait(&alldevs_cv, &alldevs_mtx);
1076 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
1077 	cv_signal(&alldevs_cv);
1078 	mutex_exit(&alldevs_mtx);
1079 }
1080 
1081 static void
1082 config_devunlink(device_t dev)
1083 {
1084 	struct cfdriver *cd = dev->dv_cfdriver;
1085 	int i;
1086 
1087 	/* Unlink from device list. */
1088 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1089 
1090 	/* Remove from cfdriver's array. */
1091 	cd->cd_devs[dev->dv_unit] = NULL;
1092 
1093 	/*
1094 	 * If the device now has no units in use, deallocate its softc array.
1095 	 */
1096 	for (i = 0; i < cd->cd_ndevs; i++)
1097 		if (cd->cd_devs[i] != NULL)
1098 			break;
1099 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
1100 		free(cd->cd_devs, M_DEVBUF);
1101 		cd->cd_devs = NULL;
1102 		cd->cd_ndevs = 0;
1103 	}
1104 }
1105 
1106 static device_t
1107 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1108 {
1109 	struct cfdriver *cd;
1110 	struct cfattach *ca;
1111 	size_t lname, lunit;
1112 	const char *xunit;
1113 	int myunit;
1114 	char num[10];
1115 	device_t dev;
1116 	void *dev_private;
1117 	const struct cfiattrdata *ia;
1118 
1119 	cd = config_cfdriver_lookup(cf->cf_name);
1120 	if (cd == NULL)
1121 		return (NULL);
1122 
1123 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1124 	if (ca == NULL)
1125 		return (NULL);
1126 
1127 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
1128 	    ca->ca_devsize < sizeof(struct device))
1129 		panic("config_devalloc");
1130 
1131 #ifndef __BROKEN_CONFIG_UNIT_USAGE
1132 	if (cf->cf_fstate == FSTATE_STAR) {
1133 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
1134 			if (cd->cd_devs[myunit] == NULL)
1135 				break;
1136 		/*
1137 		 * myunit is now the unit of the first NULL device pointer,
1138 		 * or max(cd->cd_ndevs,cf->cf_unit).
1139 		 */
1140 	} else {
1141 		myunit = cf->cf_unit;
1142 		if (myunit < cd->cd_ndevs && cd->cd_devs[myunit] != NULL)
1143 			return (NULL);
1144 	}
1145 #else
1146 	myunit = cf->cf_unit;
1147 #endif /* ! __BROKEN_CONFIG_UNIT_USAGE */
1148 
1149 	/* compute length of name and decimal expansion of unit number */
1150 	lname = strlen(cd->cd_name);
1151 	xunit = number(&num[sizeof(num)], myunit);
1152 	lunit = &num[sizeof(num)] - xunit;
1153 	if (lname + lunit > sizeof(dev->dv_xname))
1154 		panic("config_devalloc: device name too long");
1155 
1156 	/* get memory for all device vars */
1157 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
1158 	if (ca->ca_devsize > 0) {
1159 		dev_private = malloc(ca->ca_devsize, M_DEVBUF,
1160 				     M_ZERO | (cold ? M_NOWAIT : M_WAITOK));
1161 		if (dev_private == NULL)
1162 			panic("config_devalloc: memory allocation for device softc failed");
1163 	} else {
1164 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1165 		dev_private = NULL;
1166 	}
1167 
1168 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
1169 		dev = malloc(sizeof(struct device), M_DEVBUF,
1170 			     M_ZERO | (cold ? M_NOWAIT : M_WAITOK));
1171 	} else {
1172 		dev = dev_private;
1173 	}
1174 	if (dev == NULL)
1175 		panic("config_devalloc: memory allocation for device_t failed");
1176 
1177 	dev->dv_class = cd->cd_class;
1178 	dev->dv_cfdata = cf;
1179 	dev->dv_cfdriver = cd;
1180 	dev->dv_cfattach = ca;
1181 	dev->dv_unit = myunit;
1182 	dev->dv_activity_count = 0;
1183 	dev->dv_activity_handlers = NULL;
1184 	dev->dv_private = dev_private;
1185 	memcpy(dev->dv_xname, cd->cd_name, lname);
1186 	memcpy(dev->dv_xname + lname, xunit, lunit);
1187 	dev->dv_parent = parent;
1188 	if (parent != NULL)
1189 		dev->dv_depth = parent->dv_depth + 1;
1190 	else
1191 		dev->dv_depth = 0;
1192 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
1193 	dev->dv_flags |= ca->ca_flags;	/* inherit flags from class */
1194 	if (locs) {
1195 		KASSERT(parent); /* no locators at root */
1196 		ia = cfiattr_lookup(cf->cf_pspec->cfp_iattr,
1197 				    parent->dv_cfdriver);
1198 		dev->dv_locators = malloc(ia->ci_loclen * sizeof(int),
1199 					  M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1200 		memcpy(dev->dv_locators, locs, ia->ci_loclen * sizeof(int));
1201 	}
1202 	dev->dv_properties = prop_dictionary_create();
1203 	KASSERT(dev->dv_properties != NULL);
1204 
1205 	return (dev);
1206 }
1207 
1208 static void
1209 config_devdealloc(device_t dev)
1210 {
1211 
1212 	KASSERT(dev->dv_properties != NULL);
1213 	prop_object_release(dev->dv_properties);
1214 
1215 	if (dev->dv_activity_handlers)
1216 		panic("config_devdealloc with registered handlers");
1217 
1218 	if (dev->dv_locators)
1219 		free(dev->dv_locators, M_DEVBUF);
1220 
1221 	if ((dev->dv_flags & DVF_PRIV_ALLOC) != 0)
1222 		free(dev->dv_private, M_DEVBUF);
1223 
1224 	free(dev, M_DEVBUF);
1225 }
1226 
1227 /*
1228  * Attach a found device.
1229  */
1230 device_t
1231 config_attach_loc(device_t parent, cfdata_t cf,
1232 	const int *locs, void *aux, cfprint_t print)
1233 {
1234 	device_t dev;
1235 	struct cftable *ct;
1236 	const char *drvname;
1237 
1238 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1239 	if (splash_progress_state)
1240 		splash_progress_update(splash_progress_state);
1241 #endif
1242 
1243 	dev = config_devalloc(parent, cf, locs);
1244 	if (!dev)
1245 		panic("config_attach: allocation of device softc failed");
1246 
1247 	/* XXX redundant - see below? */
1248 	if (cf->cf_fstate != FSTATE_STAR) {
1249 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1250 		cf->cf_fstate = FSTATE_FOUND;
1251 	}
1252 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1253 	  else
1254 		cf->cf_unit++;
1255 #endif
1256 
1257 	config_devlink(dev);
1258 
1259 	if (config_do_twiddle)
1260 		twiddle();
1261 	else
1262 		aprint_naive("Found ");
1263 	/*
1264 	 * We want the next two printfs for normal, verbose, and quiet,
1265 	 * but not silent (in which case, we're twiddling, instead).
1266 	 */
1267 	if (parent == ROOT) {
1268 		aprint_naive("%s (root)", dev->dv_xname);
1269 		aprint_normal("%s (root)", dev->dv_xname);
1270 	} else {
1271 		aprint_naive("%s at %s", dev->dv_xname, parent->dv_xname);
1272 		aprint_normal("%s at %s", dev->dv_xname, parent->dv_xname);
1273 		if (print)
1274 			(void) (*print)(aux, NULL);
1275 	}
1276 
1277 	/*
1278 	 * Before attaching, clobber any unfound devices that are
1279 	 * otherwise identical.
1280 	 * XXX code above is redundant?
1281 	 */
1282 	drvname = dev->dv_cfdriver->cd_name;
1283 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1284 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1285 			if (STREQ(cf->cf_name, drvname) &&
1286 			    cf->cf_unit == dev->dv_unit) {
1287 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1288 					cf->cf_fstate = FSTATE_FOUND;
1289 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1290 				/*
1291 				 * Bump the unit number on all starred cfdata
1292 				 * entries for this device.
1293 				 */
1294 				if (cf->cf_fstate == FSTATE_STAR)
1295 					cf->cf_unit++;
1296 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1297 			}
1298 		}
1299 	}
1300 #ifdef __HAVE_DEVICE_REGISTER
1301 	device_register(dev, aux);
1302 #endif
1303 
1304 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1305 	if (splash_progress_state)
1306 		splash_progress_update(splash_progress_state);
1307 #endif
1308 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1309 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1310 	if (splash_progress_state)
1311 		splash_progress_update(splash_progress_state);
1312 #endif
1313 
1314 	if (!device_pmf_is_registered(dev))
1315 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1316 
1317 	config_process_deferred(&deferred_config_queue, dev);
1318 	return (dev);
1319 }
1320 
1321 device_t
1322 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1323 {
1324 
1325 	return (config_attach_loc(parent, cf, NULL, aux, print));
1326 }
1327 
1328 /*
1329  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1330  * way are silently inserted into the device tree, and their children
1331  * attached.
1332  *
1333  * Note that because pseudo-devices are attached silently, any information
1334  * the attach routine wishes to print should be prefixed with the device
1335  * name by the attach routine.
1336  */
1337 device_t
1338 config_attach_pseudo(cfdata_t cf)
1339 {
1340 	device_t dev;
1341 
1342 	dev = config_devalloc(ROOT, cf, NULL);
1343 	if (!dev)
1344 		return (NULL);
1345 
1346 	/* XXX mark busy in cfdata */
1347 
1348 	config_devlink(dev);
1349 
1350 #if 0	/* XXXJRT not yet */
1351 #ifdef __HAVE_DEVICE_REGISTER
1352 	device_register(dev, NULL);	/* like a root node */
1353 #endif
1354 #endif
1355 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1356 	config_process_deferred(&deferred_config_queue, dev);
1357 	return (dev);
1358 }
1359 
1360 /*
1361  * Detach a device.  Optionally forced (e.g. because of hardware
1362  * removal) and quiet.  Returns zero if successful, non-zero
1363  * (an error code) otherwise.
1364  *
1365  * Note that this code wants to be run from a process context, so
1366  * that the detach can sleep to allow processes which have a device
1367  * open to run and unwind their stacks.
1368  */
1369 int
1370 config_detach(device_t dev, int flags)
1371 {
1372 	struct cftable *ct;
1373 	cfdata_t cf;
1374 	const struct cfattach *ca;
1375 	struct cfdriver *cd;
1376 #ifdef DIAGNOSTIC
1377 	device_t d;
1378 #endif
1379 	int rv = 0;
1380 
1381 #ifdef DIAGNOSTIC
1382 	if (dev->dv_cfdata != NULL &&
1383 	    dev->dv_cfdata->cf_fstate != FSTATE_FOUND &&
1384 	    dev->dv_cfdata->cf_fstate != FSTATE_STAR)
1385 		panic("config_detach: bad device fstate");
1386 #endif
1387 	cd = dev->dv_cfdriver;
1388 	KASSERT(cd != NULL);
1389 
1390 	ca = dev->dv_cfattach;
1391 	KASSERT(ca != NULL);
1392 
1393 	KASSERT(curlwp != NULL);
1394 	mutex_enter(&alldevs_mtx);
1395 	if (alldevs_nwrite > 0 && alldevs_writer == NULL)
1396 		;
1397 	else while (alldevs_nread != 0 ||
1398 	       (alldevs_nwrite != 0 && alldevs_writer != curlwp))
1399 		cv_wait(&alldevs_cv, &alldevs_mtx);
1400 	if (alldevs_nwrite++ == 0)
1401 		alldevs_writer = curlwp;
1402 	mutex_exit(&alldevs_mtx);
1403 
1404 	/*
1405 	 * Ensure the device is deactivated.  If the device doesn't
1406 	 * have an activation entry point, we allow DVF_ACTIVE to
1407 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
1408 	 * device is busy, and the detach fails.
1409 	 */
1410 	if (ca->ca_activate != NULL)
1411 		rv = config_deactivate(dev);
1412 
1413 	/*
1414 	 * Try to detach the device.  If that's not possible, then
1415 	 * we either panic() (for the forced but failed case), or
1416 	 * return an error.
1417 	 */
1418 	if (rv == 0) {
1419 		if (ca->ca_detach != NULL)
1420 			rv = (*ca->ca_detach)(dev, flags);
1421 		else
1422 			rv = EOPNOTSUPP;
1423 	}
1424 	if (rv != 0) {
1425 		if ((flags & DETACH_FORCE) == 0)
1426 			goto out;
1427 		else
1428 			panic("config_detach: forced detach of %s failed (%d)",
1429 			    dev->dv_xname, rv);
1430 	}
1431 
1432 	/*
1433 	 * The device has now been successfully detached.
1434 	 */
1435 
1436 #ifdef DIAGNOSTIC
1437 	/*
1438 	 * Sanity: If you're successfully detached, you should have no
1439 	 * children.  (Note that because children must be attached
1440 	 * after parents, we only need to search the latter part of
1441 	 * the list.)
1442 	 */
1443 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1444 	    d = TAILQ_NEXT(d, dv_list)) {
1445 		if (d->dv_parent == dev) {
1446 			printf("config_detach: detached device %s"
1447 			    " has children %s\n", dev->dv_xname, d->dv_xname);
1448 			panic("config_detach");
1449 		}
1450 	}
1451 #endif
1452 
1453 	/* notify the parent that the child is gone */
1454 	if (dev->dv_parent) {
1455 		device_t p = dev->dv_parent;
1456 		if (p->dv_cfattach->ca_childdetached)
1457 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1458 	}
1459 
1460 	/*
1461 	 * Mark cfdata to show that the unit can be reused, if possible.
1462 	 */
1463 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1464 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1465 			if (STREQ(cf->cf_name, cd->cd_name)) {
1466 				if (cf->cf_fstate == FSTATE_FOUND &&
1467 				    cf->cf_unit == dev->dv_unit)
1468 					cf->cf_fstate = FSTATE_NOTFOUND;
1469 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1470 				/*
1471 				 * Note that we can only re-use a starred
1472 				 * unit number if the unit being detached
1473 				 * had the last assigned unit number.
1474 				 */
1475 				if (cf->cf_fstate == FSTATE_STAR &&
1476 				    cf->cf_unit == dev->dv_unit + 1)
1477 					cf->cf_unit--;
1478 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1479 			}
1480 		}
1481 	}
1482 
1483 	config_devunlink(dev);
1484 
1485 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1486 		aprint_normal_dev(dev, "detached\n");
1487 
1488 	config_devdealloc(dev);
1489 
1490 out:
1491 	mutex_enter(&alldevs_mtx);
1492 	if (--alldevs_nwrite == 0)
1493 		alldevs_writer = NULL;
1494 	cv_signal(&alldevs_cv);
1495 	mutex_exit(&alldevs_mtx);
1496 	return rv;
1497 }
1498 
1499 int
1500 config_detach_children(device_t parent, int flags)
1501 {
1502 	device_t dv;
1503 	deviter_t di;
1504 	int error = 0;
1505 
1506 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1507 	     dv = deviter_next(&di)) {
1508 		if (device_parent(dv) != parent)
1509 			continue;
1510 		if ((error = config_detach(dv, flags)) != 0)
1511 			break;
1512 	}
1513 	deviter_release(&di);
1514 	return error;
1515 }
1516 
1517 int
1518 config_activate(device_t dev)
1519 {
1520 	const struct cfattach *ca = dev->dv_cfattach;
1521 	int rv = 0, oflags = dev->dv_flags;
1522 
1523 	if (ca->ca_activate == NULL)
1524 		return (EOPNOTSUPP);
1525 
1526 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
1527 		dev->dv_flags |= DVF_ACTIVE;
1528 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
1529 		if (rv)
1530 			dev->dv_flags = oflags;
1531 	}
1532 	return (rv);
1533 }
1534 
1535 int
1536 config_deactivate(device_t dev)
1537 {
1538 	const struct cfattach *ca = dev->dv_cfattach;
1539 	int rv = 0, oflags = dev->dv_flags;
1540 
1541 	if (ca->ca_activate == NULL)
1542 		return (EOPNOTSUPP);
1543 
1544 	if (dev->dv_flags & DVF_ACTIVE) {
1545 		dev->dv_flags &= ~DVF_ACTIVE;
1546 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
1547 		if (rv)
1548 			dev->dv_flags = oflags;
1549 	}
1550 	return (rv);
1551 }
1552 
1553 /*
1554  * Defer the configuration of the specified device until all
1555  * of its parent's devices have been attached.
1556  */
1557 void
1558 config_defer(device_t dev, void (*func)(device_t))
1559 {
1560 	struct deferred_config *dc;
1561 
1562 	if (dev->dv_parent == NULL)
1563 		panic("config_defer: can't defer config of a root device");
1564 
1565 #ifdef DIAGNOSTIC
1566 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
1567 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1568 		if (dc->dc_dev == dev)
1569 			panic("config_defer: deferred twice");
1570 	}
1571 #endif
1572 
1573 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1574 	if (dc == NULL)
1575 		panic("config_defer: unable to allocate callback");
1576 
1577 	dc->dc_dev = dev;
1578 	dc->dc_func = func;
1579 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1580 	config_pending_incr();
1581 }
1582 
1583 /*
1584  * Defer some autoconfiguration for a device until after interrupts
1585  * are enabled.
1586  */
1587 void
1588 config_interrupts(device_t dev, void (*func)(device_t))
1589 {
1590 	struct deferred_config *dc;
1591 
1592 	/*
1593 	 * If interrupts are enabled, callback now.
1594 	 */
1595 	if (cold == 0) {
1596 		(*func)(dev);
1597 		return;
1598 	}
1599 
1600 #ifdef DIAGNOSTIC
1601 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
1602 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1603 		if (dc->dc_dev == dev)
1604 			panic("config_interrupts: deferred twice");
1605 	}
1606 #endif
1607 
1608 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1609 	if (dc == NULL)
1610 		panic("config_interrupts: unable to allocate callback");
1611 
1612 	dc->dc_dev = dev;
1613 	dc->dc_func = func;
1614 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1615 	config_pending_incr();
1616 }
1617 
1618 /*
1619  * Process a deferred configuration queue.
1620  */
1621 static void
1622 config_process_deferred(struct deferred_config_head *queue,
1623     device_t parent)
1624 {
1625 	struct deferred_config *dc, *ndc;
1626 
1627 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1628 		ndc = TAILQ_NEXT(dc, dc_queue);
1629 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1630 			TAILQ_REMOVE(queue, dc, dc_queue);
1631 			(*dc->dc_func)(dc->dc_dev);
1632 			free(dc, M_DEVBUF);
1633 			config_pending_decr();
1634 		}
1635 	}
1636 }
1637 
1638 /*
1639  * Manipulate the config_pending semaphore.
1640  */
1641 void
1642 config_pending_incr(void)
1643 {
1644 
1645 	config_pending++;
1646 }
1647 
1648 void
1649 config_pending_decr(void)
1650 {
1651 
1652 #ifdef DIAGNOSTIC
1653 	if (config_pending == 0)
1654 		panic("config_pending_decr: config_pending == 0");
1655 #endif
1656 	config_pending--;
1657 	if (config_pending == 0)
1658 		wakeup(&config_pending);
1659 }
1660 
1661 /*
1662  * Register a "finalization" routine.  Finalization routines are
1663  * called iteratively once all real devices have been found during
1664  * autoconfiguration, for as long as any one finalizer has done
1665  * any work.
1666  */
1667 int
1668 config_finalize_register(device_t dev, int (*fn)(device_t))
1669 {
1670 	struct finalize_hook *f;
1671 
1672 	/*
1673 	 * If finalization has already been done, invoke the
1674 	 * callback function now.
1675 	 */
1676 	if (config_finalize_done) {
1677 		while ((*fn)(dev) != 0)
1678 			/* loop */ ;
1679 	}
1680 
1681 	/* Ensure this isn't already on the list. */
1682 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1683 		if (f->f_func == fn && f->f_dev == dev)
1684 			return (EEXIST);
1685 	}
1686 
1687 	f = malloc(sizeof(*f), M_TEMP, M_WAITOK);
1688 	f->f_func = fn;
1689 	f->f_dev = dev;
1690 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1691 
1692 	return (0);
1693 }
1694 
1695 void
1696 config_finalize(void)
1697 {
1698 	struct finalize_hook *f;
1699 	int rv;
1700 
1701 	/* Run the hooks until none of them does any work. */
1702 	do {
1703 		rv = 0;
1704 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1705 			rv |= (*f->f_func)(f->f_dev);
1706 	} while (rv != 0);
1707 
1708 	config_finalize_done = 1;
1709 
1710 	/* Now free all the hooks. */
1711 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1712 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1713 		free(f, M_TEMP);
1714 	}
1715 }
1716 
1717 /*
1718  * device_lookup:
1719  *
1720  *	Look up a device instance for a given driver.
1721  */
1722 void *
1723 device_lookup(cfdriver_t cd, int unit)
1724 {
1725 
1726 	if (unit < 0 || unit >= cd->cd_ndevs)
1727 		return (NULL);
1728 
1729 	return (cd->cd_devs[unit]);
1730 }
1731 
1732 /*
1733  * Accessor functions for the device_t type.
1734  */
1735 devclass_t
1736 device_class(device_t dev)
1737 {
1738 
1739 	return (dev->dv_class);
1740 }
1741 
1742 cfdata_t
1743 device_cfdata(device_t dev)
1744 {
1745 
1746 	return (dev->dv_cfdata);
1747 }
1748 
1749 cfdriver_t
1750 device_cfdriver(device_t dev)
1751 {
1752 
1753 	return (dev->dv_cfdriver);
1754 }
1755 
1756 cfattach_t
1757 device_cfattach(device_t dev)
1758 {
1759 
1760 	return (dev->dv_cfattach);
1761 }
1762 
1763 int
1764 device_unit(device_t dev)
1765 {
1766 
1767 	return (dev->dv_unit);
1768 }
1769 
1770 const char *
1771 device_xname(device_t dev)
1772 {
1773 
1774 	return (dev->dv_xname);
1775 }
1776 
1777 device_t
1778 device_parent(device_t dev)
1779 {
1780 
1781 	return (dev->dv_parent);
1782 }
1783 
1784 bool
1785 device_is_active(device_t dev)
1786 {
1787 	int active_flags;
1788 
1789 	active_flags = DVF_ACTIVE;
1790 	active_flags |= DVF_CLASS_SUSPENDED;
1791 	active_flags |= DVF_DRIVER_SUSPENDED;
1792 	active_flags |= DVF_BUS_SUSPENDED;
1793 
1794 	return ((dev->dv_flags & active_flags) == DVF_ACTIVE);
1795 }
1796 
1797 bool
1798 device_is_enabled(device_t dev)
1799 {
1800 	return (dev->dv_flags & DVF_ACTIVE) == DVF_ACTIVE;
1801 }
1802 
1803 bool
1804 device_has_power(device_t dev)
1805 {
1806 	int active_flags;
1807 
1808 	active_flags = DVF_ACTIVE | DVF_BUS_SUSPENDED;
1809 
1810 	return ((dev->dv_flags & active_flags) == DVF_ACTIVE);
1811 }
1812 
1813 int
1814 device_locator(device_t dev, u_int locnum)
1815 {
1816 
1817 	KASSERT(dev->dv_locators != NULL);
1818 	return (dev->dv_locators[locnum]);
1819 }
1820 
1821 void *
1822 device_private(device_t dev)
1823 {
1824 
1825 	/*
1826 	 * The reason why device_private(NULL) is allowed is to simplify the
1827 	 * work of a lot of userspace request handlers (i.e., c/bdev
1828 	 * handlers) which grab cfdriver_t->cd_units[n].
1829 	 * It avoids having them test for it to be NULL and only then calling
1830 	 * device_private.
1831 	 */
1832 	return dev == NULL ? NULL : dev->dv_private;
1833 }
1834 
1835 prop_dictionary_t
1836 device_properties(device_t dev)
1837 {
1838 
1839 	return (dev->dv_properties);
1840 }
1841 
1842 /*
1843  * device_is_a:
1844  *
1845  *	Returns true if the device is an instance of the specified
1846  *	driver.
1847  */
1848 bool
1849 device_is_a(device_t dev, const char *dname)
1850 {
1851 
1852 	return (strcmp(dev->dv_cfdriver->cd_name, dname) == 0);
1853 }
1854 
1855 /*
1856  * device_find_by_xname:
1857  *
1858  *	Returns the device of the given name or NULL if it doesn't exist.
1859  */
1860 device_t
1861 device_find_by_xname(const char *name)
1862 {
1863 	device_t dv;
1864 	deviter_t di;
1865 
1866 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
1867 		if (strcmp(device_xname(dv), name) == 0)
1868 			break;
1869 	}
1870 	deviter_release(&di);
1871 
1872 	return dv;
1873 }
1874 
1875 /*
1876  * device_find_by_driver_unit:
1877  *
1878  *	Returns the device of the given driver name and unit or
1879  *	NULL if it doesn't exist.
1880  */
1881 device_t
1882 device_find_by_driver_unit(const char *name, int unit)
1883 {
1884 	struct cfdriver *cd;
1885 
1886 	if ((cd = config_cfdriver_lookup(name)) == NULL)
1887 		return NULL;
1888 	return device_lookup(cd, unit);
1889 }
1890 
1891 /*
1892  * Power management related functions.
1893  */
1894 
1895 bool
1896 device_pmf_is_registered(device_t dev)
1897 {
1898 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
1899 }
1900 
1901 bool
1902 device_pmf_driver_suspend(device_t dev PMF_FN_ARGS)
1903 {
1904 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
1905 		return true;
1906 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
1907 		return false;
1908 	if (*dev->dv_driver_suspend != NULL &&
1909 	    !(*dev->dv_driver_suspend)(dev PMF_FN_CALL))
1910 		return false;
1911 
1912 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
1913 	return true;
1914 }
1915 
1916 bool
1917 device_pmf_driver_resume(device_t dev PMF_FN_ARGS)
1918 {
1919 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
1920 		return true;
1921 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
1922 		return false;
1923 	if (*dev->dv_driver_resume != NULL &&
1924 	    !(*dev->dv_driver_resume)(dev PMF_FN_CALL))
1925 		return false;
1926 
1927 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
1928 	return true;
1929 }
1930 
1931 bool
1932 device_pmf_driver_shutdown(device_t dev, int how)
1933 {
1934 
1935 	if (*dev->dv_driver_shutdown != NULL &&
1936 	    !(*dev->dv_driver_shutdown)(dev, how))
1937 		return false;
1938 	return true;
1939 }
1940 
1941 bool
1942 device_pmf_driver_register(device_t dev,
1943     bool (*suspend)(device_t PMF_FN_PROTO),
1944     bool (*resume)(device_t PMF_FN_PROTO),
1945     bool (*shutdown)(device_t, int))
1946 {
1947 	dev->dv_driver_suspend = suspend;
1948 	dev->dv_driver_resume = resume;
1949 	dev->dv_driver_shutdown = shutdown;
1950 	dev->dv_flags |= DVF_POWER_HANDLERS;
1951 	return true;
1952 }
1953 
1954 void
1955 device_pmf_driver_deregister(device_t dev)
1956 {
1957 	dev->dv_driver_suspend = NULL;
1958 	dev->dv_driver_resume = NULL;
1959 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
1960 }
1961 
1962 bool
1963 device_pmf_driver_child_register(device_t dev)
1964 {
1965 	device_t parent = device_parent(dev);
1966 
1967 	if (parent == NULL || parent->dv_driver_child_register == NULL)
1968 		return true;
1969 	return (*parent->dv_driver_child_register)(dev);
1970 }
1971 
1972 void
1973 device_pmf_driver_set_child_register(device_t dev,
1974     bool (*child_register)(device_t))
1975 {
1976 	dev->dv_driver_child_register = child_register;
1977 }
1978 
1979 void *
1980 device_pmf_bus_private(device_t dev)
1981 {
1982 	return dev->dv_bus_private;
1983 }
1984 
1985 bool
1986 device_pmf_bus_suspend(device_t dev PMF_FN_ARGS)
1987 {
1988 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
1989 		return true;
1990 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
1991 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
1992 		return false;
1993 	if (*dev->dv_bus_suspend != NULL &&
1994 	    !(*dev->dv_bus_suspend)(dev PMF_FN_CALL))
1995 		return false;
1996 
1997 	dev->dv_flags |= DVF_BUS_SUSPENDED;
1998 	return true;
1999 }
2000 
2001 bool
2002 device_pmf_bus_resume(device_t dev PMF_FN_ARGS)
2003 {
2004 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2005 		return true;
2006 	if (*dev->dv_bus_resume != NULL &&
2007 	    !(*dev->dv_bus_resume)(dev PMF_FN_CALL))
2008 		return false;
2009 
2010 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2011 	return true;
2012 }
2013 
2014 bool
2015 device_pmf_bus_shutdown(device_t dev, int how)
2016 {
2017 
2018 	if (*dev->dv_bus_shutdown != NULL &&
2019 	    !(*dev->dv_bus_shutdown)(dev, how))
2020 		return false;
2021 	return true;
2022 }
2023 
2024 void
2025 device_pmf_bus_register(device_t dev, void *priv,
2026     bool (*suspend)(device_t PMF_FN_PROTO),
2027     bool (*resume)(device_t PMF_FN_PROTO),
2028     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2029 {
2030 	dev->dv_bus_private = priv;
2031 	dev->dv_bus_resume = resume;
2032 	dev->dv_bus_suspend = suspend;
2033 	dev->dv_bus_shutdown = shutdown;
2034 	dev->dv_bus_deregister = deregister;
2035 }
2036 
2037 void
2038 device_pmf_bus_deregister(device_t dev)
2039 {
2040 	if (dev->dv_bus_deregister == NULL)
2041 		return;
2042 	(*dev->dv_bus_deregister)(dev);
2043 	dev->dv_bus_private = NULL;
2044 	dev->dv_bus_suspend = NULL;
2045 	dev->dv_bus_resume = NULL;
2046 	dev->dv_bus_deregister = NULL;
2047 }
2048 
2049 void *
2050 device_pmf_class_private(device_t dev)
2051 {
2052 	return dev->dv_class_private;
2053 }
2054 
2055 bool
2056 device_pmf_class_suspend(device_t dev PMF_FN_ARGS)
2057 {
2058 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2059 		return true;
2060 	if (*dev->dv_class_suspend != NULL &&
2061 	    !(*dev->dv_class_suspend)(dev PMF_FN_CALL))
2062 		return false;
2063 
2064 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2065 	return true;
2066 }
2067 
2068 bool
2069 device_pmf_class_resume(device_t dev PMF_FN_ARGS)
2070 {
2071 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2072 		return true;
2073 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2074 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2075 		return false;
2076 	if (*dev->dv_class_resume != NULL &&
2077 	    !(*dev->dv_class_resume)(dev PMF_FN_CALL))
2078 		return false;
2079 
2080 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2081 	return true;
2082 }
2083 
2084 void
2085 device_pmf_class_register(device_t dev, void *priv,
2086     bool (*suspend)(device_t PMF_FN_PROTO),
2087     bool (*resume)(device_t PMF_FN_PROTO),
2088     void (*deregister)(device_t))
2089 {
2090 	dev->dv_class_private = priv;
2091 	dev->dv_class_suspend = suspend;
2092 	dev->dv_class_resume = resume;
2093 	dev->dv_class_deregister = deregister;
2094 }
2095 
2096 void
2097 device_pmf_class_deregister(device_t dev)
2098 {
2099 	if (dev->dv_class_deregister == NULL)
2100 		return;
2101 	(*dev->dv_class_deregister)(dev);
2102 	dev->dv_class_private = NULL;
2103 	dev->dv_class_suspend = NULL;
2104 	dev->dv_class_resume = NULL;
2105 	dev->dv_class_deregister = NULL;
2106 }
2107 
2108 bool
2109 device_active(device_t dev, devactive_t type)
2110 {
2111 	size_t i;
2112 
2113 	if (dev->dv_activity_count == 0)
2114 		return false;
2115 
2116 	for (i = 0; i < dev->dv_activity_count; ++i)
2117 		(*dev->dv_activity_handlers[i])(dev, type);
2118 
2119 	return true;
2120 }
2121 
2122 bool
2123 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2124 {
2125 	void (**new_handlers)(device_t, devactive_t);
2126 	void (**old_handlers)(device_t, devactive_t);
2127 	size_t i, new_size;
2128 	int s;
2129 
2130 	old_handlers = dev->dv_activity_handlers;
2131 
2132 	for (i = 0; i < dev->dv_activity_count; ++i) {
2133 		if (old_handlers[i] == handler)
2134 			panic("Double registering of idle handlers");
2135 	}
2136 
2137 	new_size = dev->dv_activity_count + 1;
2138 	new_handlers = malloc(sizeof(void *) * new_size, M_DEVBUF, M_WAITOK);
2139 
2140 	memcpy(new_handlers, old_handlers,
2141 	    sizeof(void *) * dev->dv_activity_count);
2142 	new_handlers[new_size - 1] = handler;
2143 
2144 	s = splhigh();
2145 	dev->dv_activity_count = new_size;
2146 	dev->dv_activity_handlers = new_handlers;
2147 	splx(s);
2148 
2149 	if (old_handlers != NULL)
2150 		free(old_handlers, M_DEVBUF);
2151 
2152 	return true;
2153 }
2154 
2155 void
2156 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2157 {
2158 	void (**new_handlers)(device_t, devactive_t);
2159 	void (**old_handlers)(device_t, devactive_t);
2160 	size_t i, new_size;
2161 	int s;
2162 
2163 	old_handlers = dev->dv_activity_handlers;
2164 
2165 	for (i = 0; i < dev->dv_activity_count; ++i) {
2166 		if (old_handlers[i] == handler)
2167 			break;
2168 	}
2169 
2170 	if (i == dev->dv_activity_count)
2171 		return; /* XXX panic? */
2172 
2173 	new_size = dev->dv_activity_count - 1;
2174 
2175 	if (new_size == 0) {
2176 		new_handlers = NULL;
2177 	} else {
2178 		new_handlers = malloc(sizeof(void *) * new_size, M_DEVBUF,
2179 		    M_WAITOK);
2180 		memcpy(new_handlers, old_handlers, sizeof(void *) * i);
2181 		memcpy(new_handlers + i, old_handlers + i + 1,
2182 		    sizeof(void *) * (new_size - i));
2183 	}
2184 
2185 	s = splhigh();
2186 	dev->dv_activity_count = new_size;
2187 	dev->dv_activity_handlers = new_handlers;
2188 	splx(s);
2189 
2190 	free(old_handlers, M_DEVBUF);
2191 }
2192 
2193 /*
2194  * Device Iteration
2195  *
2196  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2197  *     each device_t's in the device tree.
2198  *
2199  * deviter_init(di, flags): initialize the device iterator `di'
2200  *     to "walk" the device tree.  deviter_next(di) will return
2201  *     the first device_t in the device tree, or NULL if there are
2202  *     no devices.
2203  *
2204  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2205  *     caller intends to modify the device tree by calling
2206  *     config_detach(9) on devices in the order that the iterator
2207  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2208  *     nearest the "root" of the device tree to be returned, first;
2209  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2210  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2211  *     indicating both that deviter_init() should not respect any
2212  *     locks on the device tree, and that deviter_next(di) may run
2213  *     in more than one LWP before the walk has finished.
2214  *
2215  *     Only one DEVITER_F_RW iterator may be in the device tree at
2216  *     once.
2217  *
2218  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2219  *
2220  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2221  *     DEVITER_F_LEAVES_FIRST are used in combination.
2222  *
2223  * deviter_first(di, flags): initialize the device iterator `di'
2224  *     and return the first device_t in the device tree, or NULL
2225  *     if there are no devices.  The statement
2226  *
2227  *         dv = deviter_first(di);
2228  *
2229  *     is shorthand for
2230  *
2231  *         deviter_init(di);
2232  *         dv = deviter_next(di);
2233  *
2234  * deviter_next(di): return the next device_t in the device tree,
2235  *     or NULL if there are no more devices.  deviter_next(di)
2236  *     is undefined if `di' was not initialized with deviter_init() or
2237  *     deviter_first().
2238  *
2239  * deviter_release(di): stops iteration (subsequent calls to
2240  *     deviter_next() will return NULL), releases any locks and
2241  *     resources held by the device iterator.
2242  *
2243  * Device iteration does not return device_t's in any particular
2244  * order.  An iterator will never return the same device_t twice.
2245  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2246  * is called repeatedly on the same `di', it will eventually return
2247  * NULL.  It is ok to attach/detach devices during device iteration.
2248  */
2249 void
2250 deviter_init(deviter_t *di, deviter_flags_t flags)
2251 {
2252 	device_t dv;
2253 	bool rw;
2254 
2255 	mutex_enter(&alldevs_mtx);
2256 	if ((flags & DEVITER_F_SHUTDOWN) != 0) {
2257 		flags |= DEVITER_F_RW;
2258 		alldevs_nwrite++;
2259 		alldevs_writer = NULL;
2260 		alldevs_nread = 0;
2261 	} else {
2262 		rw = (flags & DEVITER_F_RW) != 0;
2263 
2264 		if (alldevs_nwrite > 0 && alldevs_writer == NULL)
2265 			;
2266 		else while ((alldevs_nwrite != 0 && alldevs_writer != curlwp) ||
2267 		       (rw && alldevs_nread != 0))
2268 			cv_wait(&alldevs_cv, &alldevs_mtx);
2269 
2270 		if (rw) {
2271 			if (alldevs_nwrite++ == 0)
2272 				alldevs_writer = curlwp;
2273 		} else
2274 			alldevs_nread++;
2275 	}
2276 	mutex_exit(&alldevs_mtx);
2277 
2278 	memset(di, 0, sizeof(*di));
2279 
2280 	di->di_flags = flags;
2281 
2282 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2283 	case DEVITER_F_LEAVES_FIRST:
2284 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2285 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2286 		break;
2287 	case DEVITER_F_ROOT_FIRST:
2288 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2289 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2290 		break;
2291 	default:
2292 		break;
2293 	}
2294 
2295 	deviter_reinit(di);
2296 }
2297 
2298 static void
2299 deviter_reinit(deviter_t *di)
2300 {
2301 	if ((di->di_flags & DEVITER_F_RW) != 0)
2302 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2303 	else
2304 		di->di_prev = TAILQ_FIRST(&alldevs);
2305 }
2306 
2307 device_t
2308 deviter_first(deviter_t *di, deviter_flags_t flags)
2309 {
2310 	deviter_init(di, flags);
2311 	return deviter_next(di);
2312 }
2313 
2314 static device_t
2315 deviter_next1(deviter_t *di)
2316 {
2317 	device_t dv;
2318 
2319 	dv = di->di_prev;
2320 
2321 	if (dv == NULL)
2322 		;
2323 	else if ((di->di_flags & DEVITER_F_RW) != 0)
2324 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2325 	else
2326 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2327 
2328 	return dv;
2329 }
2330 
2331 device_t
2332 deviter_next(deviter_t *di)
2333 {
2334 	device_t dv = NULL;
2335 
2336 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2337 	case 0:
2338 		return deviter_next1(di);
2339 	case DEVITER_F_LEAVES_FIRST:
2340 		while (di->di_curdepth >= 0) {
2341 			if ((dv = deviter_next1(di)) == NULL) {
2342 				di->di_curdepth--;
2343 				deviter_reinit(di);
2344 			} else if (dv->dv_depth == di->di_curdepth)
2345 				break;
2346 		}
2347 		return dv;
2348 	case DEVITER_F_ROOT_FIRST:
2349 		while (di->di_curdepth <= di->di_maxdepth) {
2350 			if ((dv = deviter_next1(di)) == NULL) {
2351 				di->di_curdepth++;
2352 				deviter_reinit(di);
2353 			} else if (dv->dv_depth == di->di_curdepth)
2354 				break;
2355 		}
2356 		return dv;
2357 	default:
2358 		return NULL;
2359 	}
2360 }
2361 
2362 void
2363 deviter_release(deviter_t *di)
2364 {
2365 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2366 
2367 	mutex_enter(&alldevs_mtx);
2368 	if (alldevs_nwrite > 0 && alldevs_writer == NULL)
2369 		--alldevs_nwrite;
2370 	else {
2371 
2372 		if (rw) {
2373 			if (--alldevs_nwrite == 0)
2374 				alldevs_writer = NULL;
2375 		} else
2376 			--alldevs_nread;
2377 
2378 		cv_signal(&alldevs_cv);
2379 	}
2380 	mutex_exit(&alldevs_mtx);
2381 }
2382