xref: /netbsd-src/sys/kern/subr_autoconf.c (revision cd22f25e6f6d1cc1f197fe8c5468a80f51d1c4e1)
1 /* $NetBSD: subr_autoconf.c,v 1.147 2008/04/29 14:35:21 rmind 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 1.147 2008/04/29 14:35:21 rmind 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 #include <sys/kthread.h>
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 typedef struct pmf_private {
131 	int		pp_nwait;
132 	int		pp_nlock;
133 	lwp_t		*pp_holder;
134 	kmutex_t	pp_mtx;
135 	kcondvar_t	pp_cv;
136 } pmf_private_t;
137 
138 /*
139  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
140  * devices and drivers are found via these tables.
141  */
142 extern struct cfdata cfdata[];
143 extern const short cfroots[];
144 
145 /*
146  * List of all cfdriver structures.  We use this to detect duplicates
147  * when other cfdrivers are loaded.
148  */
149 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
150 extern struct cfdriver * const cfdriver_list_initial[];
151 
152 /*
153  * Initial list of cfattach's.
154  */
155 extern const struct cfattachinit cfattachinit[];
156 
157 /*
158  * List of cfdata tables.  We always have one such list -- the one
159  * built statically when the kernel was configured.
160  */
161 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
162 static struct cftable initcftable;
163 
164 #define	ROOT ((device_t)NULL)
165 
166 struct matchinfo {
167 	cfsubmatch_t fn;
168 	struct	device *parent;
169 	const int *locs;
170 	void	*aux;
171 	struct	cfdata *match;
172 	int	pri;
173 };
174 
175 static char *number(char *, int);
176 static void mapply(struct matchinfo *, cfdata_t);
177 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
178 static void config_devdealloc(device_t);
179 static void config_makeroom(int, struct cfdriver *);
180 static void config_devlink(device_t);
181 static void config_devunlink(device_t);
182 
183 static void pmflock_debug(device_t, const char *, int);
184 static void pmflock_debug_with_flags(device_t, const char *, int PMF_FN_PROTO);
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 
203 static void config_process_deferred(struct deferred_config_head *, device_t);
204 
205 /* Hooks to finalize configuration once all real devices have been found. */
206 struct finalize_hook {
207 	TAILQ_ENTRY(finalize_hook) f_list;
208 	int (*f_func)(device_t);
209 	device_t f_dev;
210 };
211 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
212 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
213 static int config_finalize_done;
214 
215 /* list of all devices */
216 struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
217 kcondvar_t alldevs_cv;
218 kmutex_t alldevs_mtx;
219 static int alldevs_nread = 0;
220 static int alldevs_nwrite = 0;
221 static lwp_t *alldevs_writer = NULL;
222 
223 volatile int config_pending;		/* semaphore for mountroot */
224 
225 #define	STREQ(s1, s2)			\
226 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
227 
228 static int config_initialized;		/* config_init() has been called. */
229 
230 static int config_do_twiddle;
231 
232 MALLOC_DEFINE(M_PMFPRIV, "pmfpriv", "device pmf private storage");
233 
234 struct vnode *
235 opendisk(struct device *dv)
236 {
237 	int bmajor, bminor;
238 	struct vnode *tmpvn;
239 	int error;
240 	dev_t dev;
241 
242 	/*
243 	 * Lookup major number for disk block device.
244 	 */
245 	bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
246 	if (bmajor == -1)
247 		return NULL;
248 
249 	bminor = minor(device_unit(dv));
250 	/*
251 	 * Fake a temporary vnode for the disk, open it, and read
252 	 * and hash the sectors.
253 	 */
254 	dev = device_is_a(dv, "dk") ? makedev(bmajor, bminor) :
255 	    MAKEDISKDEV(bmajor, bminor, RAW_PART);
256 	if (bdevvp(dev, &tmpvn))
257 		panic("%s: can't alloc vnode for %s", __func__,
258 		    device_xname(dv));
259 	error = VOP_OPEN(tmpvn, FREAD, NOCRED);
260 	if (error) {
261 #ifndef DEBUG
262 		/*
263 		 * Ignore errors caused by missing device, partition,
264 		 * or medium.
265 		 */
266 		if (error != ENXIO && error != ENODEV)
267 #endif
268 			printf("%s: can't open dev %s (%d)\n",
269 			    __func__, device_xname(dv), error);
270 		vput(tmpvn);
271 		return NULL;
272 	}
273 
274 	return tmpvn;
275 }
276 
277 int
278 config_handle_wedges(struct device *dv, int par)
279 {
280 	struct dkwedge_list wl;
281 	struct dkwedge_info *wi;
282 	struct vnode *vn;
283 	char diskname[16];
284 	int i, error;
285 
286 	if ((vn = opendisk(dv)) == NULL)
287 		return -1;
288 
289 	wl.dkwl_bufsize = sizeof(*wi) * 16;
290 	wl.dkwl_buf = wi = malloc(wl.dkwl_bufsize, M_TEMP, M_WAITOK);
291 
292 	error = VOP_IOCTL(vn, DIOCLWEDGES, &wl, FREAD, NOCRED);
293 	VOP_CLOSE(vn, FREAD, NOCRED);
294 	vput(vn);
295 	if (error) {
296 #ifdef DEBUG_WEDGE
297 		printf("%s: List wedges returned %d\n",
298 		    device_xname(dv), error);
299 #endif
300 		free(wi, M_TEMP);
301 		return -1;
302 	}
303 
304 #ifdef DEBUG_WEDGE
305 	printf("%s: Returned %u(%u) wedges\n", device_xname(dv),
306 	    wl.dkwl_nwedges, wl.dkwl_ncopied);
307 #endif
308 	snprintf(diskname, sizeof(diskname), "%s%c", device_xname(dv),
309 	    par + 'a');
310 
311 	for (i = 0; i < wl.dkwl_ncopied; i++) {
312 #ifdef DEBUG_WEDGE
313 		printf("%s: Looking for %s in %s\n",
314 		    device_xname(dv), diskname, wi[i].dkw_wname);
315 #endif
316 		if (strcmp(wi[i].dkw_wname, diskname) == 0)
317 			break;
318 	}
319 
320 	if (i == wl.dkwl_ncopied) {
321 #ifdef DEBUG_WEDGE
322 		printf("%s: Cannot find wedge with parent %s\n",
323 		    device_xname(dv), diskname);
324 #endif
325 		free(wi, M_TEMP);
326 		return -1;
327 	}
328 
329 #ifdef DEBUG_WEDGE
330 	printf("%s: Setting boot wedge %s (%s) at %llu %llu\n",
331 		device_xname(dv), wi[i].dkw_devname, wi[i].dkw_wname,
332 		(unsigned long long)wi[i].dkw_offset,
333 		(unsigned long long)wi[i].dkw_size);
334 #endif
335 	dkwedge_set_bootwedge(dv, wi[i].dkw_offset, wi[i].dkw_size);
336 	free(wi, M_TEMP);
337 	return 0;
338 }
339 
340 /*
341  * Initialize the autoconfiguration data structures.  Normally this
342  * is done by configure(), but some platforms need to do this very
343  * early (to e.g. initialize the console).
344  */
345 void
346 config_init(void)
347 {
348 	const struct cfattachinit *cfai;
349 	int i, j;
350 
351 	if (config_initialized)
352 		return;
353 
354 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_NONE);
355 	cv_init(&alldevs_cv, "alldevs");
356 
357 	/* allcfdrivers is statically initialized. */
358 	for (i = 0; cfdriver_list_initial[i] != NULL; i++) {
359 		if (config_cfdriver_attach(cfdriver_list_initial[i]) != 0)
360 			panic("configure: duplicate `%s' drivers",
361 			    cfdriver_list_initial[i]->cd_name);
362 	}
363 
364 	for (cfai = &cfattachinit[0]; cfai->cfai_name != NULL; cfai++) {
365 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
366 			if (config_cfattach_attach(cfai->cfai_name,
367 						   cfai->cfai_list[j]) != 0)
368 				panic("configure: duplicate `%s' attachment "
369 				    "of `%s' driver",
370 				    cfai->cfai_list[j]->ca_name,
371 				    cfai->cfai_name);
372 		}
373 	}
374 
375 	initcftable.ct_cfdata = cfdata;
376 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
377 
378 	config_initialized = 1;
379 }
380 
381 void
382 config_deferred(device_t dev)
383 {
384 	config_process_deferred(&deferred_config_queue, dev);
385 	config_process_deferred(&interrupt_config_queue, dev);
386 }
387 
388 static void
389 config_interrupts_thread(void *cookie)
390 {
391 	struct deferred_config *dc;
392 
393 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
394 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
395 		(*dc->dc_func)(dc->dc_dev);
396 		free(dc, M_DEVBUF);
397 		config_pending_decr();
398 	}
399 	kthread_exit(0);
400 }
401 
402 /*
403  * Configure the system's hardware.
404  */
405 void
406 configure(void)
407 {
408 	extern void ssp_init(void);
409 	int i, s;
410 
411 	/* Initialize data structures. */
412 	config_init();
413 	pmf_init();
414 
415 #ifdef USERCONF
416 	if (boothowto & RB_USERCONF)
417 		user_config();
418 #endif
419 
420 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
421 		config_do_twiddle = 1;
422 		printf_nolog("Detecting hardware...");
423 	}
424 
425 	/*
426 	 * Do the machine-dependent portion of autoconfiguration.  This
427 	 * sets the configuration machinery here in motion by "finding"
428 	 * the root bus.  When this function returns, we expect interrupts
429 	 * to be enabled.
430 	 */
431 	cpu_configure();
432 
433 	/* Initialize SSP. */
434 	ssp_init();
435 
436 	/*
437 	 * Now that we've found all the hardware, start the real time
438 	 * and statistics clocks.
439 	 */
440 	initclocks();
441 
442 	cold = 0;	/* clocks are running, we're warm now! */
443 	s = splsched();
444 	curcpu()->ci_schedstate.spc_flags |= SPCF_RUNNING;
445 	splx(s);
446 
447 	/* Boot the secondary processors. */
448 	mp_online = true;
449 #if defined(MULTIPROCESSOR)
450 	cpu_boot_secondary_processors();
451 #endif
452 
453 	/* Setup the runqueues and scheduler. */
454 	runq_init();
455 	sched_init();
456 
457 	/*
458 	 * Create threads to call back and finish configuration for
459 	 * devices that want interrupts enabled.
460 	 */
461 	for (i = 0; i < interrupt_config_threads; i++) {
462 		(void)kthread_create(PRI_NONE, 0, NULL,
463 		    config_interrupts_thread, NULL, NULL, "config");
464 	}
465 
466 	/* Get the threads going and into any sleeps before continuing. */
467 	yield();
468 
469 	/* Lock the kernel on behalf of lwp0. */
470 	KERNEL_LOCK(1, NULL);
471 }
472 
473 /*
474  * Add a cfdriver to the system.
475  */
476 int
477 config_cfdriver_attach(struct cfdriver *cd)
478 {
479 	struct cfdriver *lcd;
480 
481 	/* Make sure this driver isn't already in the system. */
482 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
483 		if (STREQ(lcd->cd_name, cd->cd_name))
484 			return (EEXIST);
485 	}
486 
487 	LIST_INIT(&cd->cd_attach);
488 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
489 
490 	return (0);
491 }
492 
493 /*
494  * Remove a cfdriver from the system.
495  */
496 int
497 config_cfdriver_detach(struct cfdriver *cd)
498 {
499 	int i;
500 
501 	/* Make sure there are no active instances. */
502 	for (i = 0; i < cd->cd_ndevs; i++) {
503 		if (cd->cd_devs[i] != NULL)
504 			return (EBUSY);
505 	}
506 
507 	/* ...and no attachments loaded. */
508 	if (LIST_EMPTY(&cd->cd_attach) == 0)
509 		return (EBUSY);
510 
511 	LIST_REMOVE(cd, cd_list);
512 
513 	KASSERT(cd->cd_devs == NULL);
514 
515 	return (0);
516 }
517 
518 /*
519  * Look up a cfdriver by name.
520  */
521 struct cfdriver *
522 config_cfdriver_lookup(const char *name)
523 {
524 	struct cfdriver *cd;
525 
526 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
527 		if (STREQ(cd->cd_name, name))
528 			return (cd);
529 	}
530 
531 	return (NULL);
532 }
533 
534 /*
535  * Add a cfattach to the specified driver.
536  */
537 int
538 config_cfattach_attach(const char *driver, struct cfattach *ca)
539 {
540 	struct cfattach *lca;
541 	struct cfdriver *cd;
542 
543 	cd = config_cfdriver_lookup(driver);
544 	if (cd == NULL)
545 		return (ESRCH);
546 
547 	/* Make sure this attachment isn't already on this driver. */
548 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
549 		if (STREQ(lca->ca_name, ca->ca_name))
550 			return (EEXIST);
551 	}
552 
553 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
554 
555 	return (0);
556 }
557 
558 /*
559  * Remove a cfattach from the specified driver.
560  */
561 int
562 config_cfattach_detach(const char *driver, struct cfattach *ca)
563 {
564 	struct cfdriver *cd;
565 	device_t dev;
566 	int i;
567 
568 	cd = config_cfdriver_lookup(driver);
569 	if (cd == NULL)
570 		return (ESRCH);
571 
572 	/* Make sure there are no active instances. */
573 	for (i = 0; i < cd->cd_ndevs; i++) {
574 		if ((dev = cd->cd_devs[i]) == NULL)
575 			continue;
576 		if (dev->dv_cfattach == ca)
577 			return (EBUSY);
578 	}
579 
580 	LIST_REMOVE(ca, ca_list);
581 
582 	return (0);
583 }
584 
585 /*
586  * Look up a cfattach by name.
587  */
588 static struct cfattach *
589 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
590 {
591 	struct cfattach *ca;
592 
593 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
594 		if (STREQ(ca->ca_name, atname))
595 			return (ca);
596 	}
597 
598 	return (NULL);
599 }
600 
601 /*
602  * Look up a cfattach by driver/attachment name.
603  */
604 struct cfattach *
605 config_cfattach_lookup(const char *name, const char *atname)
606 {
607 	struct cfdriver *cd;
608 
609 	cd = config_cfdriver_lookup(name);
610 	if (cd == NULL)
611 		return (NULL);
612 
613 	return (config_cfattach_lookup_cd(cd, atname));
614 }
615 
616 /*
617  * Apply the matching function and choose the best.  This is used
618  * a few times and we want to keep the code small.
619  */
620 static void
621 mapply(struct matchinfo *m, cfdata_t cf)
622 {
623 	int pri;
624 
625 	if (m->fn != NULL) {
626 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
627 	} else {
628 		pri = config_match(m->parent, cf, m->aux);
629 	}
630 	if (pri > m->pri) {
631 		m->match = cf;
632 		m->pri = pri;
633 	}
634 }
635 
636 int
637 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
638 {
639 	const struct cfiattrdata *ci;
640 	const struct cflocdesc *cl;
641 	int nlocs, i;
642 
643 	ci = cfiattr_lookup(cf->cf_pspec->cfp_iattr, parent->dv_cfdriver);
644 	KASSERT(ci);
645 	nlocs = ci->ci_loclen;
646 	for (i = 0; i < nlocs; i++) {
647 		cl = &ci->ci_locdesc[i];
648 		/* !cld_defaultstr means no default value */
649 		if ((!(cl->cld_defaultstr)
650 		     || (cf->cf_loc[i] != cl->cld_default))
651 		    && cf->cf_loc[i] != locs[i])
652 			return (0);
653 	}
654 
655 	return (config_match(parent, cf, aux));
656 }
657 
658 /*
659  * Helper function: check whether the driver supports the interface attribute
660  * and return its descriptor structure.
661  */
662 static const struct cfiattrdata *
663 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
664 {
665 	const struct cfiattrdata * const *cpp;
666 
667 	if (cd->cd_attrs == NULL)
668 		return (0);
669 
670 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
671 		if (STREQ((*cpp)->ci_name, ia)) {
672 			/* Match. */
673 			return (*cpp);
674 		}
675 	}
676 	return (0);
677 }
678 
679 /*
680  * Lookup an interface attribute description by name.
681  * If the driver is given, consider only its supported attributes.
682  */
683 const struct cfiattrdata *
684 cfiattr_lookup(const char *name, const struct cfdriver *cd)
685 {
686 	const struct cfdriver *d;
687 	const struct cfiattrdata *ia;
688 
689 	if (cd)
690 		return (cfdriver_get_iattr(cd, name));
691 
692 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
693 		ia = cfdriver_get_iattr(d, name);
694 		if (ia)
695 			return (ia);
696 	}
697 	return (0);
698 }
699 
700 /*
701  * Determine if `parent' is a potential parent for a device spec based
702  * on `cfp'.
703  */
704 static int
705 cfparent_match(const device_t parent, const struct cfparent *cfp)
706 {
707 	struct cfdriver *pcd;
708 
709 	/* We don't match root nodes here. */
710 	if (cfp == NULL)
711 		return (0);
712 
713 	pcd = parent->dv_cfdriver;
714 	KASSERT(pcd != NULL);
715 
716 	/*
717 	 * First, ensure this parent has the correct interface
718 	 * attribute.
719 	 */
720 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
721 		return (0);
722 
723 	/*
724 	 * If no specific parent device instance was specified (i.e.
725 	 * we're attaching to the attribute only), we're done!
726 	 */
727 	if (cfp->cfp_parent == NULL)
728 		return (1);
729 
730 	/*
731 	 * Check the parent device's name.
732 	 */
733 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
734 		return (0);	/* not the same parent */
735 
736 	/*
737 	 * Make sure the unit number matches.
738 	 */
739 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
740 	    cfp->cfp_unit == parent->dv_unit)
741 		return (1);
742 
743 	/* Unit numbers don't match. */
744 	return (0);
745 }
746 
747 /*
748  * Helper for config_cfdata_attach(): check all devices whether it could be
749  * parent any attachment in the config data table passed, and rescan.
750  */
751 static void
752 rescan_with_cfdata(const struct cfdata *cf)
753 {
754 	device_t d;
755 	const struct cfdata *cf1;
756 	deviter_t di;
757 
758 
759 	/*
760 	 * "alldevs" is likely longer than an LKM's cfdata, so make it
761 	 * the outer loop.
762 	 */
763 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
764 
765 		if (!(d->dv_cfattach->ca_rescan))
766 			continue;
767 
768 		for (cf1 = cf; cf1->cf_name; cf1++) {
769 
770 			if (!cfparent_match(d, cf1->cf_pspec))
771 				continue;
772 
773 			(*d->dv_cfattach->ca_rescan)(d,
774 				cf1->cf_pspec->cfp_iattr, cf1->cf_loc);
775 		}
776 	}
777 	deviter_release(&di);
778 }
779 
780 /*
781  * Attach a supplemental config data table and rescan potential
782  * parent devices if required.
783  */
784 int
785 config_cfdata_attach(cfdata_t cf, int scannow)
786 {
787 	struct cftable *ct;
788 
789 	ct = malloc(sizeof(struct cftable), M_DEVBUF, M_WAITOK);
790 	ct->ct_cfdata = cf;
791 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
792 
793 	if (scannow)
794 		rescan_with_cfdata(cf);
795 
796 	return (0);
797 }
798 
799 /*
800  * Helper for config_cfdata_detach: check whether a device is
801  * found through any attachment in the config data table.
802  */
803 static int
804 dev_in_cfdata(const struct device *d, const struct cfdata *cf)
805 {
806 	const struct cfdata *cf1;
807 
808 	for (cf1 = cf; cf1->cf_name; cf1++)
809 		if (d->dv_cfdata == cf1)
810 			return (1);
811 
812 	return (0);
813 }
814 
815 /*
816  * Detach a supplemental config data table. Detach all devices found
817  * through that table (and thus keeping references to it) before.
818  */
819 int
820 config_cfdata_detach(cfdata_t cf)
821 {
822 	device_t d;
823 	int error = 0;
824 	struct cftable *ct;
825 	deviter_t di;
826 
827 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
828 	     d = deviter_next(&di)) {
829 		if (!dev_in_cfdata(d, cf))
830 			continue;
831 		if ((error = config_detach(d, 0)) != 0)
832 			break;
833 	}
834 	deviter_release(&di);
835 	if (error) {
836 		aprint_error_dev(d, "unable to detach instance\n");
837 		return error;
838 	}
839 
840 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
841 		if (ct->ct_cfdata == cf) {
842 			TAILQ_REMOVE(&allcftables, ct, ct_list);
843 			free(ct, M_DEVBUF);
844 			return (0);
845 		}
846 	}
847 
848 	/* not found -- shouldn't happen */
849 	return (EINVAL);
850 }
851 
852 /*
853  * Invoke the "match" routine for a cfdata entry on behalf of
854  * an external caller, usually a "submatch" routine.
855  */
856 int
857 config_match(device_t parent, cfdata_t cf, void *aux)
858 {
859 	struct cfattach *ca;
860 
861 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
862 	if (ca == NULL) {
863 		/* No attachment for this entry, oh well. */
864 		return (0);
865 	}
866 
867 	return ((*ca->ca_match)(parent, cf, aux));
868 }
869 
870 /*
871  * Iterate over all potential children of some device, calling the given
872  * function (default being the child's match function) for each one.
873  * Nonzero returns are matches; the highest value returned is considered
874  * the best match.  Return the `found child' if we got a match, or NULL
875  * otherwise.  The `aux' pointer is simply passed on through.
876  *
877  * Note that this function is designed so that it can be used to apply
878  * an arbitrary function to all potential children (its return value
879  * can be ignored).
880  */
881 cfdata_t
882 config_search_loc(cfsubmatch_t fn, device_t parent,
883 		  const char *ifattr, const int *locs, void *aux)
884 {
885 	struct cftable *ct;
886 	cfdata_t cf;
887 	struct matchinfo m;
888 
889 	KASSERT(config_initialized);
890 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
891 
892 	m.fn = fn;
893 	m.parent = parent;
894 	m.locs = locs;
895 	m.aux = aux;
896 	m.match = NULL;
897 	m.pri = 0;
898 
899 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
900 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
901 
902 			/* We don't match root nodes here. */
903 			if (!cf->cf_pspec)
904 				continue;
905 
906 			/*
907 			 * Skip cf if no longer eligible, otherwise scan
908 			 * through parents for one matching `parent', and
909 			 * try match function.
910 			 */
911 			if (cf->cf_fstate == FSTATE_FOUND)
912 				continue;
913 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
914 			    cf->cf_fstate == FSTATE_DSTAR)
915 				continue;
916 
917 			/*
918 			 * If an interface attribute was specified,
919 			 * consider only children which attach to
920 			 * that attribute.
921 			 */
922 			if (ifattr && !STREQ(ifattr, cf->cf_pspec->cfp_iattr))
923 				continue;
924 
925 			if (cfparent_match(parent, cf->cf_pspec))
926 				mapply(&m, cf);
927 		}
928 	}
929 	return (m.match);
930 }
931 
932 cfdata_t
933 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
934     void *aux)
935 {
936 
937 	return (config_search_loc(fn, parent, ifattr, NULL, aux));
938 }
939 
940 /*
941  * Find the given root device.
942  * This is much like config_search, but there is no parent.
943  * Don't bother with multiple cfdata tables; the root node
944  * must always be in the initial table.
945  */
946 cfdata_t
947 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
948 {
949 	cfdata_t cf;
950 	const short *p;
951 	struct matchinfo m;
952 
953 	m.fn = fn;
954 	m.parent = ROOT;
955 	m.aux = aux;
956 	m.match = NULL;
957 	m.pri = 0;
958 	m.locs = 0;
959 	/*
960 	 * Look at root entries for matching name.  We do not bother
961 	 * with found-state here since only one root should ever be
962 	 * searched (and it must be done first).
963 	 */
964 	for (p = cfroots; *p >= 0; p++) {
965 		cf = &cfdata[*p];
966 		if (strcmp(cf->cf_name, rootname) == 0)
967 			mapply(&m, cf);
968 	}
969 	return (m.match);
970 }
971 
972 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
973 
974 /*
975  * The given `aux' argument describes a device that has been found
976  * on the given parent, but not necessarily configured.  Locate the
977  * configuration data for that device (using the submatch function
978  * provided, or using candidates' cd_match configuration driver
979  * functions) and attach it, and return true.  If the device was
980  * not configured, call the given `print' function and return 0.
981  */
982 device_t
983 config_found_sm_loc(device_t parent,
984 		const char *ifattr, const int *locs, void *aux,
985 		cfprint_t print, cfsubmatch_t submatch)
986 {
987 	cfdata_t cf;
988 
989 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
990 	if (splash_progress_state)
991 		splash_progress_update(splash_progress_state);
992 #endif
993 
994 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
995 		return(config_attach_loc(parent, cf, locs, aux, print));
996 	if (print) {
997 		if (config_do_twiddle)
998 			twiddle();
999 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
1000 	}
1001 
1002 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1003 	if (splash_progress_state)
1004 		splash_progress_update(splash_progress_state);
1005 #endif
1006 
1007 	return (NULL);
1008 }
1009 
1010 device_t
1011 config_found_ia(device_t parent, const char *ifattr, void *aux,
1012     cfprint_t print)
1013 {
1014 
1015 	return (config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL));
1016 }
1017 
1018 device_t
1019 config_found(device_t parent, void *aux, cfprint_t print)
1020 {
1021 
1022 	return (config_found_sm_loc(parent, NULL, NULL, aux, print, NULL));
1023 }
1024 
1025 /*
1026  * As above, but for root devices.
1027  */
1028 device_t
1029 config_rootfound(const char *rootname, void *aux)
1030 {
1031 	cfdata_t cf;
1032 
1033 	if ((cf = config_rootsearch((cfsubmatch_t)NULL, rootname, aux)) != NULL)
1034 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
1035 	aprint_error("root device %s not configured\n", rootname);
1036 	return (NULL);
1037 }
1038 
1039 /* just like sprintf(buf, "%d") except that it works from the end */
1040 static char *
1041 number(char *ep, int n)
1042 {
1043 
1044 	*--ep = 0;
1045 	while (n >= 10) {
1046 		*--ep = (n % 10) + '0';
1047 		n /= 10;
1048 	}
1049 	*--ep = n + '0';
1050 	return (ep);
1051 }
1052 
1053 /*
1054  * Expand the size of the cd_devs array if necessary.
1055  */
1056 static void
1057 config_makeroom(int n, struct cfdriver *cd)
1058 {
1059 	int old, new;
1060 	void **nsp;
1061 
1062 	if (n < cd->cd_ndevs)
1063 		return;
1064 
1065 	/*
1066 	 * Need to expand the array.
1067 	 */
1068 	old = cd->cd_ndevs;
1069 	if (old == 0)
1070 		new = 4;
1071 	else
1072 		new = old * 2;
1073 	while (new <= n)
1074 		new *= 2;
1075 	cd->cd_ndevs = new;
1076 	nsp = malloc(new * sizeof(void *), M_DEVBUF,
1077 	    cold ? M_NOWAIT : M_WAITOK);
1078 	if (nsp == NULL)
1079 		panic("config_attach: %sing dev array",
1080 		    old != 0 ? "expand" : "creat");
1081 	memset(nsp + old, 0, (new - old) * sizeof(void *));
1082 	if (old != 0) {
1083 		memcpy(nsp, cd->cd_devs, old * sizeof(void *));
1084 		free(cd->cd_devs, M_DEVBUF);
1085 	}
1086 	cd->cd_devs = nsp;
1087 }
1088 
1089 static void
1090 config_devlink(device_t dev)
1091 {
1092 	struct cfdriver *cd = dev->dv_cfdriver;
1093 
1094 	/* put this device in the devices array */
1095 	config_makeroom(dev->dv_unit, cd);
1096 	if (cd->cd_devs[dev->dv_unit])
1097 		panic("config_attach: duplicate %s", device_xname(dev));
1098 	cd->cd_devs[dev->dv_unit] = dev;
1099 
1100 	/* It is safe to add a device to the tail of the list while
1101 	 * readers are in the list, but not while a writer is in
1102 	 * the list.  Wait for any writer to complete.
1103 	 */
1104 	mutex_enter(&alldevs_mtx);
1105 	while (alldevs_nwrite != 0 && alldevs_writer != curlwp)
1106 		cv_wait(&alldevs_cv, &alldevs_mtx);
1107 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
1108 	cv_signal(&alldevs_cv);
1109 	mutex_exit(&alldevs_mtx);
1110 }
1111 
1112 static void
1113 config_devunlink(device_t dev)
1114 {
1115 	struct cfdriver *cd = dev->dv_cfdriver;
1116 	int i;
1117 
1118 	/* Unlink from device list. */
1119 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1120 
1121 	/* Remove from cfdriver's array. */
1122 	cd->cd_devs[dev->dv_unit] = NULL;
1123 
1124 	/*
1125 	 * If the device now has no units in use, deallocate its softc array.
1126 	 */
1127 	for (i = 0; i < cd->cd_ndevs; i++)
1128 		if (cd->cd_devs[i] != NULL)
1129 			break;
1130 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
1131 		free(cd->cd_devs, M_DEVBUF);
1132 		cd->cd_devs = NULL;
1133 		cd->cd_ndevs = 0;
1134 	}
1135 }
1136 
1137 static device_t
1138 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1139 {
1140 	struct cfdriver *cd;
1141 	struct cfattach *ca;
1142 	size_t lname, lunit;
1143 	const char *xunit;
1144 	int myunit;
1145 	char num[10];
1146 	device_t dev;
1147 	void *dev_private;
1148 	const struct cfiattrdata *ia;
1149 
1150 	cd = config_cfdriver_lookup(cf->cf_name);
1151 	if (cd == NULL)
1152 		return (NULL);
1153 
1154 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1155 	if (ca == NULL)
1156 		return (NULL);
1157 
1158 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
1159 	    ca->ca_devsize < sizeof(struct device))
1160 		panic("config_devalloc: %s", cf->cf_atname);
1161 
1162 #ifndef __BROKEN_CONFIG_UNIT_USAGE
1163 	if (cf->cf_fstate == FSTATE_STAR) {
1164 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
1165 			if (cd->cd_devs[myunit] == NULL)
1166 				break;
1167 		/*
1168 		 * myunit is now the unit of the first NULL device pointer,
1169 		 * or max(cd->cd_ndevs,cf->cf_unit).
1170 		 */
1171 	} else {
1172 		myunit = cf->cf_unit;
1173 		if (myunit < cd->cd_ndevs && cd->cd_devs[myunit] != NULL)
1174 			return (NULL);
1175 	}
1176 #else
1177 	myunit = cf->cf_unit;
1178 #endif /* ! __BROKEN_CONFIG_UNIT_USAGE */
1179 
1180 	/* compute length of name and decimal expansion of unit number */
1181 	lname = strlen(cd->cd_name);
1182 	xunit = number(&num[sizeof(num)], myunit);
1183 	lunit = &num[sizeof(num)] - xunit;
1184 	if (lname + lunit > sizeof(dev->dv_xname))
1185 		panic("config_devalloc: device name too long");
1186 
1187 	/* get memory for all device vars */
1188 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
1189 	if (ca->ca_devsize > 0) {
1190 		dev_private = malloc(ca->ca_devsize, M_DEVBUF,
1191 				     M_ZERO | (cold ? M_NOWAIT : M_WAITOK));
1192 		if (dev_private == NULL)
1193 			panic("config_devalloc: memory allocation for device softc failed");
1194 	} else {
1195 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1196 		dev_private = NULL;
1197 	}
1198 
1199 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
1200 		dev = malloc(sizeof(struct device), M_DEVBUF,
1201 			     M_ZERO | (cold ? M_NOWAIT : M_WAITOK));
1202 	} else {
1203 		dev = dev_private;
1204 	}
1205 	if (dev == NULL)
1206 		panic("config_devalloc: memory allocation for device_t failed");
1207 
1208 	dev->dv_class = cd->cd_class;
1209 	dev->dv_cfdata = cf;
1210 	dev->dv_cfdriver = cd;
1211 	dev->dv_cfattach = ca;
1212 	dev->dv_unit = myunit;
1213 	dev->dv_activity_count = 0;
1214 	dev->dv_activity_handlers = NULL;
1215 	dev->dv_private = dev_private;
1216 	memcpy(dev->dv_xname, cd->cd_name, lname);
1217 	memcpy(dev->dv_xname + lname, xunit, lunit);
1218 	dev->dv_parent = parent;
1219 	if (parent != NULL)
1220 		dev->dv_depth = parent->dv_depth + 1;
1221 	else
1222 		dev->dv_depth = 0;
1223 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
1224 	dev->dv_flags |= ca->ca_flags;	/* inherit flags from class */
1225 	if (locs) {
1226 		KASSERT(parent); /* no locators at root */
1227 		ia = cfiattr_lookup(cf->cf_pspec->cfp_iattr,
1228 				    parent->dv_cfdriver);
1229 		dev->dv_locators = malloc(ia->ci_loclen * sizeof(int),
1230 					  M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1231 		memcpy(dev->dv_locators, locs, ia->ci_loclen * sizeof(int));
1232 	}
1233 	dev->dv_properties = prop_dictionary_create();
1234 	KASSERT(dev->dv_properties != NULL);
1235 
1236 	return (dev);
1237 }
1238 
1239 static void
1240 config_devdealloc(device_t dev)
1241 {
1242 
1243 	KASSERT(dev->dv_properties != NULL);
1244 	prop_object_release(dev->dv_properties);
1245 
1246 	if (dev->dv_activity_handlers)
1247 		panic("config_devdealloc with registered handlers");
1248 
1249 	if (dev->dv_locators)
1250 		free(dev->dv_locators, M_DEVBUF);
1251 
1252 	if ((dev->dv_flags & DVF_PRIV_ALLOC) != 0 && dev->dv_private != NULL)
1253 		free(dev->dv_private, M_DEVBUF);
1254 
1255 	free(dev, M_DEVBUF);
1256 }
1257 
1258 /*
1259  * Attach a found device.
1260  */
1261 device_t
1262 config_attach_loc(device_t parent, cfdata_t cf,
1263 	const int *locs, void *aux, cfprint_t print)
1264 {
1265 	device_t dev;
1266 	struct cftable *ct;
1267 	const char *drvname;
1268 
1269 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1270 	if (splash_progress_state)
1271 		splash_progress_update(splash_progress_state);
1272 #endif
1273 
1274 	dev = config_devalloc(parent, cf, locs);
1275 	if (!dev)
1276 		panic("config_attach: allocation of device softc failed");
1277 
1278 	/* XXX redundant - see below? */
1279 	if (cf->cf_fstate != FSTATE_STAR) {
1280 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1281 		cf->cf_fstate = FSTATE_FOUND;
1282 	}
1283 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1284 	  else
1285 		cf->cf_unit++;
1286 #endif
1287 
1288 	config_devlink(dev);
1289 
1290 	if (config_do_twiddle)
1291 		twiddle();
1292 	else
1293 		aprint_naive("Found ");
1294 	/*
1295 	 * We want the next two printfs for normal, verbose, and quiet,
1296 	 * but not silent (in which case, we're twiddling, instead).
1297 	 */
1298 	if (parent == ROOT) {
1299 		aprint_naive("%s (root)", device_xname(dev));
1300 		aprint_normal("%s (root)", device_xname(dev));
1301 	} else {
1302 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
1303 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
1304 		if (print)
1305 			(void) (*print)(aux, NULL);
1306 	}
1307 
1308 	/*
1309 	 * Before attaching, clobber any unfound devices that are
1310 	 * otherwise identical.
1311 	 * XXX code above is redundant?
1312 	 */
1313 	drvname = dev->dv_cfdriver->cd_name;
1314 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1315 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1316 			if (STREQ(cf->cf_name, drvname) &&
1317 			    cf->cf_unit == dev->dv_unit) {
1318 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1319 					cf->cf_fstate = FSTATE_FOUND;
1320 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1321 				/*
1322 				 * Bump the unit number on all starred cfdata
1323 				 * entries for this device.
1324 				 */
1325 				if (cf->cf_fstate == FSTATE_STAR)
1326 					cf->cf_unit++;
1327 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1328 			}
1329 		}
1330 	}
1331 #ifdef __HAVE_DEVICE_REGISTER
1332 	device_register(dev, aux);
1333 #endif
1334 
1335 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1336 	if (splash_progress_state)
1337 		splash_progress_update(splash_progress_state);
1338 #endif
1339 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1340 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1341 	if (splash_progress_state)
1342 		splash_progress_update(splash_progress_state);
1343 #endif
1344 
1345 	if (!device_pmf_is_registered(dev))
1346 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1347 
1348 	config_process_deferred(&deferred_config_queue, dev);
1349 	return (dev);
1350 }
1351 
1352 device_t
1353 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1354 {
1355 
1356 	return (config_attach_loc(parent, cf, NULL, aux, print));
1357 }
1358 
1359 /*
1360  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1361  * way are silently inserted into the device tree, and their children
1362  * attached.
1363  *
1364  * Note that because pseudo-devices are attached silently, any information
1365  * the attach routine wishes to print should be prefixed with the device
1366  * name by the attach routine.
1367  */
1368 device_t
1369 config_attach_pseudo(cfdata_t cf)
1370 {
1371 	device_t dev;
1372 
1373 	dev = config_devalloc(ROOT, cf, NULL);
1374 	if (!dev)
1375 		return (NULL);
1376 
1377 	/* XXX mark busy in cfdata */
1378 
1379 	config_devlink(dev);
1380 
1381 #if 0	/* XXXJRT not yet */
1382 #ifdef __HAVE_DEVICE_REGISTER
1383 	device_register(dev, NULL);	/* like a root node */
1384 #endif
1385 #endif
1386 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1387 	config_process_deferred(&deferred_config_queue, dev);
1388 	return (dev);
1389 }
1390 
1391 /*
1392  * Detach a device.  Optionally forced (e.g. because of hardware
1393  * removal) and quiet.  Returns zero if successful, non-zero
1394  * (an error code) otherwise.
1395  *
1396  * Note that this code wants to be run from a process context, so
1397  * that the detach can sleep to allow processes which have a device
1398  * open to run and unwind their stacks.
1399  */
1400 int
1401 config_detach(device_t dev, int flags)
1402 {
1403 	struct cftable *ct;
1404 	cfdata_t cf;
1405 	const struct cfattach *ca;
1406 	struct cfdriver *cd;
1407 #ifdef DIAGNOSTIC
1408 	device_t d;
1409 #endif
1410 	int rv = 0;
1411 
1412 #ifdef DIAGNOSTIC
1413 	if (dev->dv_cfdata != NULL &&
1414 	    dev->dv_cfdata->cf_fstate != FSTATE_FOUND &&
1415 	    dev->dv_cfdata->cf_fstate != FSTATE_STAR)
1416 		panic("config_detach: bad device fstate");
1417 #endif
1418 	cd = dev->dv_cfdriver;
1419 	KASSERT(cd != NULL);
1420 
1421 	ca = dev->dv_cfattach;
1422 	KASSERT(ca != NULL);
1423 
1424 	KASSERT(curlwp != NULL);
1425 	mutex_enter(&alldevs_mtx);
1426 	if (alldevs_nwrite > 0 && alldevs_writer == NULL)
1427 		;
1428 	else while (alldevs_nread != 0 ||
1429 	       (alldevs_nwrite != 0 && alldevs_writer != curlwp))
1430 		cv_wait(&alldevs_cv, &alldevs_mtx);
1431 	if (alldevs_nwrite++ == 0)
1432 		alldevs_writer = curlwp;
1433 	mutex_exit(&alldevs_mtx);
1434 
1435 	/*
1436 	 * Ensure the device is deactivated.  If the device doesn't
1437 	 * have an activation entry point, we allow DVF_ACTIVE to
1438 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
1439 	 * device is busy, and the detach fails.
1440 	 */
1441 	if (ca->ca_activate != NULL)
1442 		rv = config_deactivate(dev);
1443 
1444 	/*
1445 	 * Try to detach the device.  If that's not possible, then
1446 	 * we either panic() (for the forced but failed case), or
1447 	 * return an error.
1448 	 */
1449 	if (rv == 0) {
1450 		if (ca->ca_detach != NULL)
1451 			rv = (*ca->ca_detach)(dev, flags);
1452 		else
1453 			rv = EOPNOTSUPP;
1454 	}
1455 	if (rv != 0) {
1456 		if ((flags & DETACH_FORCE) == 0)
1457 			goto out;
1458 		else
1459 			panic("config_detach: forced detach of %s failed (%d)",
1460 			    device_xname(dev), rv);
1461 	}
1462 
1463 	/*
1464 	 * The device has now been successfully detached.
1465 	 */
1466 
1467 #ifdef DIAGNOSTIC
1468 	/*
1469 	 * Sanity: If you're successfully detached, you should have no
1470 	 * children.  (Note that because children must be attached
1471 	 * after parents, we only need to search the latter part of
1472 	 * the list.)
1473 	 */
1474 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1475 	    d = TAILQ_NEXT(d, dv_list)) {
1476 		if (d->dv_parent == dev) {
1477 			printf("config_detach: detached device %s"
1478 			    " has children %s\n", device_xname(dev), device_xname(d));
1479 			panic("config_detach");
1480 		}
1481 	}
1482 #endif
1483 
1484 	/* notify the parent that the child is gone */
1485 	if (dev->dv_parent) {
1486 		device_t p = dev->dv_parent;
1487 		if (p->dv_cfattach->ca_childdetached)
1488 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1489 	}
1490 
1491 	/*
1492 	 * Mark cfdata to show that the unit can be reused, if possible.
1493 	 */
1494 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1495 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1496 			if (STREQ(cf->cf_name, cd->cd_name)) {
1497 				if (cf->cf_fstate == FSTATE_FOUND &&
1498 				    cf->cf_unit == dev->dv_unit)
1499 					cf->cf_fstate = FSTATE_NOTFOUND;
1500 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1501 				/*
1502 				 * Note that we can only re-use a starred
1503 				 * unit number if the unit being detached
1504 				 * had the last assigned unit number.
1505 				 */
1506 				if (cf->cf_fstate == FSTATE_STAR &&
1507 				    cf->cf_unit == dev->dv_unit + 1)
1508 					cf->cf_unit--;
1509 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1510 			}
1511 		}
1512 	}
1513 
1514 	config_devunlink(dev);
1515 
1516 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1517 		aprint_normal_dev(dev, "detached\n");
1518 
1519 	config_devdealloc(dev);
1520 
1521 out:
1522 	mutex_enter(&alldevs_mtx);
1523 	if (--alldevs_nwrite == 0)
1524 		alldevs_writer = NULL;
1525 	cv_signal(&alldevs_cv);
1526 	mutex_exit(&alldevs_mtx);
1527 	return rv;
1528 }
1529 
1530 int
1531 config_detach_children(device_t parent, int flags)
1532 {
1533 	device_t dv;
1534 	deviter_t di;
1535 	int error = 0;
1536 
1537 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1538 	     dv = deviter_next(&di)) {
1539 		if (device_parent(dv) != parent)
1540 			continue;
1541 		if ((error = config_detach(dv, flags)) != 0)
1542 			break;
1543 	}
1544 	deviter_release(&di);
1545 	return error;
1546 }
1547 
1548 int
1549 config_activate(device_t dev)
1550 {
1551 	const struct cfattach *ca = dev->dv_cfattach;
1552 	int rv = 0, oflags = dev->dv_flags;
1553 
1554 	if (ca->ca_activate == NULL)
1555 		return (EOPNOTSUPP);
1556 
1557 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
1558 		dev->dv_flags |= DVF_ACTIVE;
1559 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
1560 		if (rv)
1561 			dev->dv_flags = oflags;
1562 	}
1563 	return (rv);
1564 }
1565 
1566 int
1567 config_deactivate(device_t dev)
1568 {
1569 	const struct cfattach *ca = dev->dv_cfattach;
1570 	int rv = 0, oflags = dev->dv_flags;
1571 
1572 	if (ca->ca_activate == NULL)
1573 		return (EOPNOTSUPP);
1574 
1575 	if (dev->dv_flags & DVF_ACTIVE) {
1576 		dev->dv_flags &= ~DVF_ACTIVE;
1577 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
1578 		if (rv)
1579 			dev->dv_flags = oflags;
1580 	}
1581 	return (rv);
1582 }
1583 
1584 /*
1585  * Defer the configuration of the specified device until all
1586  * of its parent's devices have been attached.
1587  */
1588 void
1589 config_defer(device_t dev, void (*func)(device_t))
1590 {
1591 	struct deferred_config *dc;
1592 
1593 	if (dev->dv_parent == NULL)
1594 		panic("config_defer: can't defer config of a root device");
1595 
1596 #ifdef DIAGNOSTIC
1597 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
1598 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1599 		if (dc->dc_dev == dev)
1600 			panic("config_defer: deferred twice");
1601 	}
1602 #endif
1603 
1604 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1605 	if (dc == NULL)
1606 		panic("config_defer: unable to allocate callback");
1607 
1608 	dc->dc_dev = dev;
1609 	dc->dc_func = func;
1610 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1611 	config_pending_incr();
1612 }
1613 
1614 /*
1615  * Defer some autoconfiguration for a device until after interrupts
1616  * are enabled.
1617  */
1618 void
1619 config_interrupts(device_t dev, void (*func)(device_t))
1620 {
1621 	struct deferred_config *dc;
1622 
1623 	/*
1624 	 * If interrupts are enabled, callback now.
1625 	 */
1626 	if (cold == 0) {
1627 		(*func)(dev);
1628 		return;
1629 	}
1630 
1631 #ifdef DIAGNOSTIC
1632 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
1633 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1634 		if (dc->dc_dev == dev)
1635 			panic("config_interrupts: deferred twice");
1636 	}
1637 #endif
1638 
1639 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1640 	if (dc == NULL)
1641 		panic("config_interrupts: unable to allocate callback");
1642 
1643 	dc->dc_dev = dev;
1644 	dc->dc_func = func;
1645 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1646 	config_pending_incr();
1647 }
1648 
1649 /*
1650  * Process a deferred configuration queue.
1651  */
1652 static void
1653 config_process_deferred(struct deferred_config_head *queue,
1654     device_t parent)
1655 {
1656 	struct deferred_config *dc, *ndc;
1657 
1658 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1659 		ndc = TAILQ_NEXT(dc, dc_queue);
1660 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1661 			TAILQ_REMOVE(queue, dc, dc_queue);
1662 			(*dc->dc_func)(dc->dc_dev);
1663 			free(dc, M_DEVBUF);
1664 			config_pending_decr();
1665 		}
1666 	}
1667 }
1668 
1669 /*
1670  * Manipulate the config_pending semaphore.
1671  */
1672 void
1673 config_pending_incr(void)
1674 {
1675 
1676 	config_pending++;
1677 }
1678 
1679 void
1680 config_pending_decr(void)
1681 {
1682 
1683 #ifdef DIAGNOSTIC
1684 	if (config_pending == 0)
1685 		panic("config_pending_decr: config_pending == 0");
1686 #endif
1687 	config_pending--;
1688 	if (config_pending == 0)
1689 		wakeup(&config_pending);
1690 }
1691 
1692 /*
1693  * Register a "finalization" routine.  Finalization routines are
1694  * called iteratively once all real devices have been found during
1695  * autoconfiguration, for as long as any one finalizer has done
1696  * any work.
1697  */
1698 int
1699 config_finalize_register(device_t dev, int (*fn)(device_t))
1700 {
1701 	struct finalize_hook *f;
1702 
1703 	/*
1704 	 * If finalization has already been done, invoke the
1705 	 * callback function now.
1706 	 */
1707 	if (config_finalize_done) {
1708 		while ((*fn)(dev) != 0)
1709 			/* loop */ ;
1710 	}
1711 
1712 	/* Ensure this isn't already on the list. */
1713 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1714 		if (f->f_func == fn && f->f_dev == dev)
1715 			return (EEXIST);
1716 	}
1717 
1718 	f = malloc(sizeof(*f), M_TEMP, M_WAITOK);
1719 	f->f_func = fn;
1720 	f->f_dev = dev;
1721 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1722 
1723 	return (0);
1724 }
1725 
1726 void
1727 config_finalize(void)
1728 {
1729 	struct finalize_hook *f;
1730 	struct pdevinit *pdev;
1731 	extern struct pdevinit pdevinit[];
1732 	int errcnt, rv;
1733 
1734 	/*
1735 	 * Now that device driver threads have been created, wait for
1736 	 * them to finish any deferred autoconfiguration.
1737 	 */
1738 	while (config_pending)
1739 		(void) tsleep(&config_pending, PWAIT, "cfpend", hz);
1740 
1741 	/* Attach pseudo-devices. */
1742 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
1743 		(*pdev->pdev_attach)(pdev->pdev_count);
1744 
1745 	/* Run the hooks until none of them does any work. */
1746 	do {
1747 		rv = 0;
1748 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1749 			rv |= (*f->f_func)(f->f_dev);
1750 	} while (rv != 0);
1751 
1752 	config_finalize_done = 1;
1753 
1754 	/* Now free all the hooks. */
1755 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1756 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1757 		free(f, M_TEMP);
1758 	}
1759 
1760 	errcnt = aprint_get_error_count();
1761 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
1762 	    (boothowto & AB_VERBOSE) == 0) {
1763 		if (config_do_twiddle) {
1764 			config_do_twiddle = 0;
1765 			printf_nolog("done.\n");
1766 		}
1767 		if (errcnt != 0) {
1768 			printf("WARNING: %d error%s while detecting hardware; "
1769 			    "check system log.\n", errcnt,
1770 			    errcnt == 1 ? "" : "s");
1771 		}
1772 	}
1773 }
1774 
1775 /*
1776  * device_lookup:
1777  *
1778  *	Look up a device instance for a given driver.
1779  */
1780 void *
1781 device_lookup(cfdriver_t cd, int unit)
1782 {
1783 
1784 	if (unit < 0 || unit >= cd->cd_ndevs)
1785 		return (NULL);
1786 
1787 	return (cd->cd_devs[unit]);
1788 }
1789 
1790 /*
1791  * device_lookup:
1792  *
1793  *	Look up a device instance for a given driver.
1794  */
1795 void *
1796 device_lookup_private(cfdriver_t cd, int unit)
1797 {
1798 	device_t dv;
1799 
1800 	if (unit < 0 || unit >= cd->cd_ndevs)
1801 		return NULL;
1802 
1803 	if ((dv = cd->cd_devs[unit]) == NULL)
1804 		return NULL;
1805 
1806 	return dv->dv_private;
1807 }
1808 
1809 /*
1810  * Accessor functions for the device_t type.
1811  */
1812 devclass_t
1813 device_class(device_t dev)
1814 {
1815 
1816 	return (dev->dv_class);
1817 }
1818 
1819 cfdata_t
1820 device_cfdata(device_t dev)
1821 {
1822 
1823 	return (dev->dv_cfdata);
1824 }
1825 
1826 cfdriver_t
1827 device_cfdriver(device_t dev)
1828 {
1829 
1830 	return (dev->dv_cfdriver);
1831 }
1832 
1833 cfattach_t
1834 device_cfattach(device_t dev)
1835 {
1836 
1837 	return (dev->dv_cfattach);
1838 }
1839 
1840 int
1841 device_unit(device_t dev)
1842 {
1843 
1844 	return (dev->dv_unit);
1845 }
1846 
1847 const char *
1848 device_xname(device_t dev)
1849 {
1850 
1851 	return (dev->dv_xname);
1852 }
1853 
1854 device_t
1855 device_parent(device_t dev)
1856 {
1857 
1858 	return (dev->dv_parent);
1859 }
1860 
1861 bool
1862 device_is_active(device_t dev)
1863 {
1864 	int active_flags;
1865 
1866 	active_flags = DVF_ACTIVE;
1867 	active_flags |= DVF_CLASS_SUSPENDED;
1868 	active_flags |= DVF_DRIVER_SUSPENDED;
1869 	active_flags |= DVF_BUS_SUSPENDED;
1870 
1871 	return ((dev->dv_flags & active_flags) == DVF_ACTIVE);
1872 }
1873 
1874 bool
1875 device_is_enabled(device_t dev)
1876 {
1877 	return (dev->dv_flags & DVF_ACTIVE) == DVF_ACTIVE;
1878 }
1879 
1880 bool
1881 device_has_power(device_t dev)
1882 {
1883 	int active_flags;
1884 
1885 	active_flags = DVF_ACTIVE | DVF_BUS_SUSPENDED;
1886 
1887 	return ((dev->dv_flags & active_flags) == DVF_ACTIVE);
1888 }
1889 
1890 int
1891 device_locator(device_t dev, u_int locnum)
1892 {
1893 
1894 	KASSERT(dev->dv_locators != NULL);
1895 	return (dev->dv_locators[locnum]);
1896 }
1897 
1898 void *
1899 device_private(device_t dev)
1900 {
1901 
1902 	/*
1903 	 * The reason why device_private(NULL) is allowed is to simplify the
1904 	 * work of a lot of userspace request handlers (i.e., c/bdev
1905 	 * handlers) which grab cfdriver_t->cd_units[n].
1906 	 * It avoids having them test for it to be NULL and only then calling
1907 	 * device_private.
1908 	 */
1909 	return dev == NULL ? NULL : dev->dv_private;
1910 }
1911 
1912 prop_dictionary_t
1913 device_properties(device_t dev)
1914 {
1915 
1916 	return (dev->dv_properties);
1917 }
1918 
1919 /*
1920  * device_is_a:
1921  *
1922  *	Returns true if the device is an instance of the specified
1923  *	driver.
1924  */
1925 bool
1926 device_is_a(device_t dev, const char *dname)
1927 {
1928 
1929 	return (strcmp(dev->dv_cfdriver->cd_name, dname) == 0);
1930 }
1931 
1932 /*
1933  * device_find_by_xname:
1934  *
1935  *	Returns the device of the given name or NULL if it doesn't exist.
1936  */
1937 device_t
1938 device_find_by_xname(const char *name)
1939 {
1940 	device_t dv;
1941 	deviter_t di;
1942 
1943 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
1944 		if (strcmp(device_xname(dv), name) == 0)
1945 			break;
1946 	}
1947 	deviter_release(&di);
1948 
1949 	return dv;
1950 }
1951 
1952 /*
1953  * device_find_by_driver_unit:
1954  *
1955  *	Returns the device of the given driver name and unit or
1956  *	NULL if it doesn't exist.
1957  */
1958 device_t
1959 device_find_by_driver_unit(const char *name, int unit)
1960 {
1961 	struct cfdriver *cd;
1962 
1963 	if ((cd = config_cfdriver_lookup(name)) == NULL)
1964 		return NULL;
1965 	return device_lookup(cd, unit);
1966 }
1967 
1968 /*
1969  * Power management related functions.
1970  */
1971 
1972 bool
1973 device_pmf_is_registered(device_t dev)
1974 {
1975 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
1976 }
1977 
1978 bool
1979 device_pmf_driver_suspend(device_t dev PMF_FN_ARGS)
1980 {
1981 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
1982 		return true;
1983 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
1984 		return false;
1985 	if (*dev->dv_driver_suspend != NULL &&
1986 	    !(*dev->dv_driver_suspend)(dev PMF_FN_CALL))
1987 		return false;
1988 
1989 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
1990 	return true;
1991 }
1992 
1993 bool
1994 device_pmf_driver_resume(device_t dev PMF_FN_ARGS)
1995 {
1996 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
1997 		return true;
1998 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
1999 		return false;
2000 	if ((flags & PMF_F_SELF) != 0 && !device_is_self_suspended(dev))
2001 		return false;
2002 	if (*dev->dv_driver_resume != NULL &&
2003 	    !(*dev->dv_driver_resume)(dev PMF_FN_CALL))
2004 		return false;
2005 
2006 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2007 	return true;
2008 }
2009 
2010 bool
2011 device_pmf_driver_shutdown(device_t dev, int how)
2012 {
2013 
2014 	if (*dev->dv_driver_shutdown != NULL &&
2015 	    !(*dev->dv_driver_shutdown)(dev, how))
2016 		return false;
2017 	return true;
2018 }
2019 
2020 bool
2021 device_pmf_driver_register(device_t dev,
2022     bool (*suspend)(device_t PMF_FN_PROTO),
2023     bool (*resume)(device_t PMF_FN_PROTO),
2024     bool (*shutdown)(device_t, int))
2025 {
2026 	pmf_private_t *pp;
2027 
2028 	if ((pp = malloc(sizeof(*pp), M_PMFPRIV, M_NOWAIT|M_ZERO)) == NULL)
2029 		return false;
2030 	mutex_init(&pp->pp_mtx, MUTEX_DEFAULT, IPL_NONE);
2031 	cv_init(&pp->pp_cv, "pmfsusp");
2032 	dev->dv_pmf_private = pp;
2033 
2034 	dev->dv_driver_suspend = suspend;
2035 	dev->dv_driver_resume = resume;
2036 	dev->dv_driver_shutdown = shutdown;
2037 	dev->dv_flags |= DVF_POWER_HANDLERS;
2038 	return true;
2039 }
2040 
2041 static const char *
2042 curlwp_name(void)
2043 {
2044 	if (curlwp->l_name != NULL)
2045 		return curlwp->l_name;
2046 	else
2047 		return curlwp->l_proc->p_comm;
2048 }
2049 
2050 void
2051 device_pmf_driver_deregister(device_t dev)
2052 {
2053 	pmf_private_t *pp = dev->dv_pmf_private;
2054 
2055 	dev->dv_driver_suspend = NULL;
2056 	dev->dv_driver_resume = NULL;
2057 
2058 	dev->dv_pmf_private = NULL;
2059 
2060 	mutex_enter(&pp->pp_mtx);
2061 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2062 	while (pp->pp_nlock > 0 || pp->pp_nwait > 0) {
2063 		/* Wake a thread that waits for the lock.  That
2064 		 * thread will fail to acquire the lock, and then
2065 		 * it will wake the next thread that waits for the
2066 		 * lock, or else it will wake us.
2067 		 */
2068 		cv_signal(&pp->pp_cv);
2069 		pmflock_debug(dev, __func__, __LINE__);
2070 		cv_wait(&pp->pp_cv, &pp->pp_mtx);
2071 		pmflock_debug(dev, __func__, __LINE__);
2072 	}
2073 	mutex_exit(&pp->pp_mtx);
2074 
2075 	cv_destroy(&pp->pp_cv);
2076 	mutex_destroy(&pp->pp_mtx);
2077 	free(pp, M_PMFPRIV);
2078 }
2079 
2080 bool
2081 device_pmf_driver_child_register(device_t dev)
2082 {
2083 	device_t parent = device_parent(dev);
2084 
2085 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2086 		return true;
2087 	return (*parent->dv_driver_child_register)(dev);
2088 }
2089 
2090 void
2091 device_pmf_driver_set_child_register(device_t dev,
2092     bool (*child_register)(device_t))
2093 {
2094 	dev->dv_driver_child_register = child_register;
2095 }
2096 
2097 void
2098 device_pmf_self_resume(device_t dev PMF_FN_ARGS)
2099 {
2100 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2101 	if ((dev->dv_flags & DVF_SELF_SUSPENDED) != 0)
2102 		dev->dv_flags &= ~DVF_SELF_SUSPENDED;
2103 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2104 }
2105 
2106 bool
2107 device_is_self_suspended(device_t dev)
2108 {
2109 	return (dev->dv_flags & DVF_SELF_SUSPENDED) != 0;
2110 }
2111 
2112 void
2113 device_pmf_self_suspend(device_t dev PMF_FN_ARGS)
2114 {
2115 	bool self = (flags & PMF_F_SELF) != 0;
2116 
2117 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2118 
2119 	if (!self)
2120 		dev->dv_flags &= ~DVF_SELF_SUSPENDED;
2121 	else if (device_is_active(dev))
2122 		dev->dv_flags |= DVF_SELF_SUSPENDED;
2123 
2124 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2125 }
2126 
2127 static void
2128 pmflock_debug(device_t dev, const char *func, int line)
2129 {
2130 	pmf_private_t *pp = device_pmf_private(dev);
2131 
2132 	aprint_debug_dev(dev, "%s.%d, %s pp_nlock %d pp_nwait %d dv_flags %x\n",
2133 	    func, line, curlwp_name(), pp->pp_nlock, pp->pp_nwait,
2134 	    dev->dv_flags);
2135 }
2136 
2137 static void
2138 pmflock_debug_with_flags(device_t dev, const char *func, int line PMF_FN_ARGS)
2139 {
2140 	pmf_private_t *pp = device_pmf_private(dev);
2141 
2142 	aprint_debug_dev(dev, "%s.%d, %s pp_nlock %d pp_nwait %d dv_flags %x "
2143 	    "flags " PMF_FLAGS_FMT "\n", func, line, curlwp_name(),
2144 	    pp->pp_nlock, pp->pp_nwait, dev->dv_flags PMF_FN_CALL);
2145 }
2146 
2147 static bool
2148 device_pmf_lock1(device_t dev PMF_FN_ARGS)
2149 {
2150 	pmf_private_t *pp = device_pmf_private(dev);
2151 
2152 	while (pp->pp_nlock > 0 && pp->pp_holder != curlwp &&
2153 	       device_pmf_is_registered(dev)) {
2154 		pp->pp_nwait++;
2155 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2156 		cv_wait(&pp->pp_cv, &pp->pp_mtx);
2157 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2158 		pp->pp_nwait--;
2159 	}
2160 	if (!device_pmf_is_registered(dev)) {
2161 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2162 		/* We could not acquire the lock, but some other thread may
2163 		 * wait for it, also.  Wake that thread.
2164 		 */
2165 		cv_signal(&pp->pp_cv);
2166 		return false;
2167 	}
2168 	pp->pp_nlock++;
2169 	pp->pp_holder = curlwp;
2170 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2171 	return true;
2172 }
2173 
2174 bool
2175 device_pmf_lock(device_t dev PMF_FN_ARGS)
2176 {
2177 	bool rc;
2178 	pmf_private_t *pp = device_pmf_private(dev);
2179 
2180 	mutex_enter(&pp->pp_mtx);
2181 	rc = device_pmf_lock1(dev PMF_FN_CALL);
2182 	mutex_exit(&pp->pp_mtx);
2183 
2184 	return rc;
2185 }
2186 
2187 void
2188 device_pmf_unlock(device_t dev PMF_FN_ARGS)
2189 {
2190 	pmf_private_t *pp = device_pmf_private(dev);
2191 
2192 	KASSERT(pp->pp_nlock > 0);
2193 	mutex_enter(&pp->pp_mtx);
2194 	if (--pp->pp_nlock == 0)
2195 		pp->pp_holder = NULL;
2196 	cv_signal(&pp->pp_cv);
2197 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2198 	mutex_exit(&pp->pp_mtx);
2199 }
2200 
2201 void *
2202 device_pmf_private(device_t dev)
2203 {
2204 	return dev->dv_pmf_private;
2205 }
2206 
2207 void *
2208 device_pmf_bus_private(device_t dev)
2209 {
2210 	return dev->dv_bus_private;
2211 }
2212 
2213 bool
2214 device_pmf_bus_suspend(device_t dev PMF_FN_ARGS)
2215 {
2216 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2217 		return true;
2218 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2219 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2220 		return false;
2221 	if (*dev->dv_bus_suspend != NULL &&
2222 	    !(*dev->dv_bus_suspend)(dev PMF_FN_CALL))
2223 		return false;
2224 
2225 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2226 	return true;
2227 }
2228 
2229 bool
2230 device_pmf_bus_resume(device_t dev PMF_FN_ARGS)
2231 {
2232 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2233 		return true;
2234 	if ((flags & PMF_F_SELF) != 0 && !device_is_self_suspended(dev))
2235 		return false;
2236 	if (*dev->dv_bus_resume != NULL &&
2237 	    !(*dev->dv_bus_resume)(dev PMF_FN_CALL))
2238 		return false;
2239 
2240 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2241 	return true;
2242 }
2243 
2244 bool
2245 device_pmf_bus_shutdown(device_t dev, int how)
2246 {
2247 
2248 	if (*dev->dv_bus_shutdown != NULL &&
2249 	    !(*dev->dv_bus_shutdown)(dev, how))
2250 		return false;
2251 	return true;
2252 }
2253 
2254 void
2255 device_pmf_bus_register(device_t dev, void *priv,
2256     bool (*suspend)(device_t PMF_FN_PROTO),
2257     bool (*resume)(device_t PMF_FN_PROTO),
2258     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2259 {
2260 	dev->dv_bus_private = priv;
2261 	dev->dv_bus_resume = resume;
2262 	dev->dv_bus_suspend = suspend;
2263 	dev->dv_bus_shutdown = shutdown;
2264 	dev->dv_bus_deregister = deregister;
2265 }
2266 
2267 void
2268 device_pmf_bus_deregister(device_t dev)
2269 {
2270 	if (dev->dv_bus_deregister == NULL)
2271 		return;
2272 	(*dev->dv_bus_deregister)(dev);
2273 	dev->dv_bus_private = NULL;
2274 	dev->dv_bus_suspend = NULL;
2275 	dev->dv_bus_resume = NULL;
2276 	dev->dv_bus_deregister = NULL;
2277 }
2278 
2279 void *
2280 device_pmf_class_private(device_t dev)
2281 {
2282 	return dev->dv_class_private;
2283 }
2284 
2285 bool
2286 device_pmf_class_suspend(device_t dev PMF_FN_ARGS)
2287 {
2288 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2289 		return true;
2290 	if (*dev->dv_class_suspend != NULL &&
2291 	    !(*dev->dv_class_suspend)(dev PMF_FN_CALL))
2292 		return false;
2293 
2294 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2295 	return true;
2296 }
2297 
2298 bool
2299 device_pmf_class_resume(device_t dev PMF_FN_ARGS)
2300 {
2301 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2302 		return true;
2303 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2304 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2305 		return false;
2306 	if (*dev->dv_class_resume != NULL &&
2307 	    !(*dev->dv_class_resume)(dev PMF_FN_CALL))
2308 		return false;
2309 
2310 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2311 	return true;
2312 }
2313 
2314 void
2315 device_pmf_class_register(device_t dev, void *priv,
2316     bool (*suspend)(device_t PMF_FN_PROTO),
2317     bool (*resume)(device_t PMF_FN_PROTO),
2318     void (*deregister)(device_t))
2319 {
2320 	dev->dv_class_private = priv;
2321 	dev->dv_class_suspend = suspend;
2322 	dev->dv_class_resume = resume;
2323 	dev->dv_class_deregister = deregister;
2324 }
2325 
2326 void
2327 device_pmf_class_deregister(device_t dev)
2328 {
2329 	if (dev->dv_class_deregister == NULL)
2330 		return;
2331 	(*dev->dv_class_deregister)(dev);
2332 	dev->dv_class_private = NULL;
2333 	dev->dv_class_suspend = NULL;
2334 	dev->dv_class_resume = NULL;
2335 	dev->dv_class_deregister = NULL;
2336 }
2337 
2338 bool
2339 device_active(device_t dev, devactive_t type)
2340 {
2341 	size_t i;
2342 
2343 	if (dev->dv_activity_count == 0)
2344 		return false;
2345 
2346 	for (i = 0; i < dev->dv_activity_count; ++i)
2347 		(*dev->dv_activity_handlers[i])(dev, type);
2348 
2349 	return true;
2350 }
2351 
2352 bool
2353 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2354 {
2355 	void (**new_handlers)(device_t, devactive_t);
2356 	void (**old_handlers)(device_t, devactive_t);
2357 	size_t i, new_size;
2358 	int s;
2359 
2360 	old_handlers = dev->dv_activity_handlers;
2361 
2362 	for (i = 0; i < dev->dv_activity_count; ++i) {
2363 		if (old_handlers[i] == handler)
2364 			panic("Double registering of idle handlers");
2365 	}
2366 
2367 	new_size = dev->dv_activity_count + 1;
2368 	new_handlers = malloc(sizeof(void *) * new_size, M_DEVBUF, M_WAITOK);
2369 
2370 	memcpy(new_handlers, old_handlers,
2371 	    sizeof(void *) * dev->dv_activity_count);
2372 	new_handlers[new_size - 1] = handler;
2373 
2374 	s = splhigh();
2375 	dev->dv_activity_count = new_size;
2376 	dev->dv_activity_handlers = new_handlers;
2377 	splx(s);
2378 
2379 	if (old_handlers != NULL)
2380 		free(old_handlers, M_DEVBUF);
2381 
2382 	return true;
2383 }
2384 
2385 void
2386 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2387 {
2388 	void (**new_handlers)(device_t, devactive_t);
2389 	void (**old_handlers)(device_t, devactive_t);
2390 	size_t i, new_size;
2391 	int s;
2392 
2393 	old_handlers = dev->dv_activity_handlers;
2394 
2395 	for (i = 0; i < dev->dv_activity_count; ++i) {
2396 		if (old_handlers[i] == handler)
2397 			break;
2398 	}
2399 
2400 	if (i == dev->dv_activity_count)
2401 		return; /* XXX panic? */
2402 
2403 	new_size = dev->dv_activity_count - 1;
2404 
2405 	if (new_size == 0) {
2406 		new_handlers = NULL;
2407 	} else {
2408 		new_handlers = malloc(sizeof(void *) * new_size, M_DEVBUF,
2409 		    M_WAITOK);
2410 		memcpy(new_handlers, old_handlers, sizeof(void *) * i);
2411 		memcpy(new_handlers + i, old_handlers + i + 1,
2412 		    sizeof(void *) * (new_size - i));
2413 	}
2414 
2415 	s = splhigh();
2416 	dev->dv_activity_count = new_size;
2417 	dev->dv_activity_handlers = new_handlers;
2418 	splx(s);
2419 
2420 	free(old_handlers, M_DEVBUF);
2421 }
2422 
2423 /*
2424  * Device Iteration
2425  *
2426  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2427  *     each device_t's in the device tree.
2428  *
2429  * deviter_init(di, flags): initialize the device iterator `di'
2430  *     to "walk" the device tree.  deviter_next(di) will return
2431  *     the first device_t in the device tree, or NULL if there are
2432  *     no devices.
2433  *
2434  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2435  *     caller intends to modify the device tree by calling
2436  *     config_detach(9) on devices in the order that the iterator
2437  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2438  *     nearest the "root" of the device tree to be returned, first;
2439  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2440  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2441  *     indicating both that deviter_init() should not respect any
2442  *     locks on the device tree, and that deviter_next(di) may run
2443  *     in more than one LWP before the walk has finished.
2444  *
2445  *     Only one DEVITER_F_RW iterator may be in the device tree at
2446  *     once.
2447  *
2448  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2449  *
2450  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2451  *     DEVITER_F_LEAVES_FIRST are used in combination.
2452  *
2453  * deviter_first(di, flags): initialize the device iterator `di'
2454  *     and return the first device_t in the device tree, or NULL
2455  *     if there are no devices.  The statement
2456  *
2457  *         dv = deviter_first(di);
2458  *
2459  *     is shorthand for
2460  *
2461  *         deviter_init(di);
2462  *         dv = deviter_next(di);
2463  *
2464  * deviter_next(di): return the next device_t in the device tree,
2465  *     or NULL if there are no more devices.  deviter_next(di)
2466  *     is undefined if `di' was not initialized with deviter_init() or
2467  *     deviter_first().
2468  *
2469  * deviter_release(di): stops iteration (subsequent calls to
2470  *     deviter_next() will return NULL), releases any locks and
2471  *     resources held by the device iterator.
2472  *
2473  * Device iteration does not return device_t's in any particular
2474  * order.  An iterator will never return the same device_t twice.
2475  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2476  * is called repeatedly on the same `di', it will eventually return
2477  * NULL.  It is ok to attach/detach devices during device iteration.
2478  */
2479 void
2480 deviter_init(deviter_t *di, deviter_flags_t flags)
2481 {
2482 	device_t dv;
2483 	bool rw;
2484 
2485 	mutex_enter(&alldevs_mtx);
2486 	if ((flags & DEVITER_F_SHUTDOWN) != 0) {
2487 		flags |= DEVITER_F_RW;
2488 		alldevs_nwrite++;
2489 		alldevs_writer = NULL;
2490 		alldevs_nread = 0;
2491 	} else {
2492 		rw = (flags & DEVITER_F_RW) != 0;
2493 
2494 		if (alldevs_nwrite > 0 && alldevs_writer == NULL)
2495 			;
2496 		else while ((alldevs_nwrite != 0 && alldevs_writer != curlwp) ||
2497 		       (rw && alldevs_nread != 0))
2498 			cv_wait(&alldevs_cv, &alldevs_mtx);
2499 
2500 		if (rw) {
2501 			if (alldevs_nwrite++ == 0)
2502 				alldevs_writer = curlwp;
2503 		} else
2504 			alldevs_nread++;
2505 	}
2506 	mutex_exit(&alldevs_mtx);
2507 
2508 	memset(di, 0, sizeof(*di));
2509 
2510 	di->di_flags = flags;
2511 
2512 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2513 	case DEVITER_F_LEAVES_FIRST:
2514 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2515 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2516 		break;
2517 	case DEVITER_F_ROOT_FIRST:
2518 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2519 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2520 		break;
2521 	default:
2522 		break;
2523 	}
2524 
2525 	deviter_reinit(di);
2526 }
2527 
2528 static void
2529 deviter_reinit(deviter_t *di)
2530 {
2531 	if ((di->di_flags & DEVITER_F_RW) != 0)
2532 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2533 	else
2534 		di->di_prev = TAILQ_FIRST(&alldevs);
2535 }
2536 
2537 device_t
2538 deviter_first(deviter_t *di, deviter_flags_t flags)
2539 {
2540 	deviter_init(di, flags);
2541 	return deviter_next(di);
2542 }
2543 
2544 static device_t
2545 deviter_next1(deviter_t *di)
2546 {
2547 	device_t dv;
2548 
2549 	dv = di->di_prev;
2550 
2551 	if (dv == NULL)
2552 		;
2553 	else if ((di->di_flags & DEVITER_F_RW) != 0)
2554 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2555 	else
2556 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2557 
2558 	return dv;
2559 }
2560 
2561 device_t
2562 deviter_next(deviter_t *di)
2563 {
2564 	device_t dv = NULL;
2565 
2566 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2567 	case 0:
2568 		return deviter_next1(di);
2569 	case DEVITER_F_LEAVES_FIRST:
2570 		while (di->di_curdepth >= 0) {
2571 			if ((dv = deviter_next1(di)) == NULL) {
2572 				di->di_curdepth--;
2573 				deviter_reinit(di);
2574 			} else if (dv->dv_depth == di->di_curdepth)
2575 				break;
2576 		}
2577 		return dv;
2578 	case DEVITER_F_ROOT_FIRST:
2579 		while (di->di_curdepth <= di->di_maxdepth) {
2580 			if ((dv = deviter_next1(di)) == NULL) {
2581 				di->di_curdepth++;
2582 				deviter_reinit(di);
2583 			} else if (dv->dv_depth == di->di_curdepth)
2584 				break;
2585 		}
2586 		return dv;
2587 	default:
2588 		return NULL;
2589 	}
2590 }
2591 
2592 void
2593 deviter_release(deviter_t *di)
2594 {
2595 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2596 
2597 	mutex_enter(&alldevs_mtx);
2598 	if (alldevs_nwrite > 0 && alldevs_writer == NULL)
2599 		--alldevs_nwrite;
2600 	else {
2601 
2602 		if (rw) {
2603 			if (--alldevs_nwrite == 0)
2604 				alldevs_writer = NULL;
2605 		} else
2606 			--alldevs_nread;
2607 
2608 		cv_signal(&alldevs_cv);
2609 	}
2610 	mutex_exit(&alldevs_mtx);
2611 }
2612