xref: /netbsd-src/sys/kern/subr_autoconf.c (revision de4fa6c51a9708fc05f88b618fa6fad87c9508ec)
1 /* $NetBSD: subr_autoconf.c,v 1.180 2009/09/03 15:20:08 pooka 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 1.180 2009/09/03 15:20:08 pooka Exp $");
81 
82 #ifdef _KERNEL_OPT
83 #include "opt_ddb.h"
84 #include "drvctl.h"
85 #endif
86 
87 #include <sys/param.h>
88 #include <sys/device.h>
89 #include <sys/disklabel.h>
90 #include <sys/conf.h>
91 #include <sys/kauth.h>
92 #include <sys/malloc.h>
93 #include <sys/kmem.h>
94 #include <sys/systm.h>
95 #include <sys/kernel.h>
96 #include <sys/errno.h>
97 #include <sys/proc.h>
98 #include <sys/reboot.h>
99 #include <sys/kthread.h>
100 #include <sys/buf.h>
101 #include <sys/dirent.h>
102 #include <sys/vnode.h>
103 #include <sys/mount.h>
104 #include <sys/namei.h>
105 #include <sys/unistd.h>
106 #include <sys/fcntl.h>
107 #include <sys/lockf.h>
108 #include <sys/callout.h>
109 #include <sys/devmon.h>
110 #include <sys/cpu.h>
111 #include <sys/sysctl.h>
112 
113 #include <sys/disk.h>
114 
115 #include <machine/limits.h>
116 
117 #if defined(__i386__) && defined(_KERNEL_OPT)
118 #include "opt_splash.h"
119 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
120 #include <dev/splash/splash.h>
121 extern struct splash_progress *splash_progress_state;
122 #endif
123 #endif
124 
125 /*
126  * Autoconfiguration subroutines.
127  */
128 
129 /*
130  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
131  * devices and drivers are found via these tables.
132  */
133 extern struct cfdata cfdata[];
134 extern const short cfroots[];
135 
136 /*
137  * List of all cfdriver structures.  We use this to detect duplicates
138  * when other cfdrivers are loaded.
139  */
140 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
141 extern struct cfdriver * const cfdriver_list_initial[];
142 
143 /*
144  * Initial list of cfattach's.
145  */
146 extern const struct cfattachinit cfattachinit[];
147 
148 /*
149  * List of cfdata tables.  We always have one such list -- the one
150  * built statically when the kernel was configured.
151  */
152 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
153 static struct cftable initcftable;
154 
155 #define	ROOT ((device_t)NULL)
156 
157 struct matchinfo {
158 	cfsubmatch_t fn;
159 	struct	device *parent;
160 	const int *locs;
161 	void	*aux;
162 	struct	cfdata *match;
163 	int	pri;
164 };
165 
166 static char *number(char *, int);
167 static void mapply(struct matchinfo *, cfdata_t);
168 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
169 static void config_devdealloc(device_t);
170 static void config_makeroom(int, struct cfdriver *);
171 static void config_devlink(device_t);
172 static void config_devunlink(device_t);
173 
174 static void pmflock_debug(device_t, const char *, int);
175 static void pmflock_debug_with_flags(device_t, const char *, int PMF_FN_PROTO);
176 
177 static device_t deviter_next1(deviter_t *);
178 static void deviter_reinit(deviter_t *);
179 
180 struct deferred_config {
181 	TAILQ_ENTRY(deferred_config) dc_queue;
182 	device_t dc_dev;
183 	void (*dc_func)(device_t);
184 };
185 
186 TAILQ_HEAD(deferred_config_head, deferred_config);
187 
188 struct deferred_config_head deferred_config_queue =
189 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
190 struct deferred_config_head interrupt_config_queue =
191 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
192 int interrupt_config_threads = 8;
193 
194 static void config_process_deferred(struct deferred_config_head *, device_t);
195 
196 /* Hooks to finalize configuration once all real devices have been found. */
197 struct finalize_hook {
198 	TAILQ_ENTRY(finalize_hook) f_list;
199 	int (*f_func)(device_t);
200 	device_t f_dev;
201 };
202 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
203 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
204 static int config_finalize_done;
205 
206 /* list of all devices */
207 struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
208 kcondvar_t alldevs_cv;
209 kmutex_t alldevs_mtx;
210 static int alldevs_nread = 0;
211 static int alldevs_nwrite = 0;
212 static lwp_t *alldevs_writer = NULL;
213 
214 static int config_pending;		/* semaphore for mountroot */
215 static kmutex_t config_misc_lock;
216 static kcondvar_t config_misc_cv;
217 
218 static int detachall = 0;
219 
220 #define	STREQ(s1, s2)			\
221 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
222 
223 static int config_initialized;		/* config_init() has been called. */
224 
225 static int config_do_twiddle;
226 static callout_t config_twiddle_ch;
227 
228 struct vnode *
229 opendisk(struct device *dv)
230 {
231 	int bmajor, bminor;
232 	struct vnode *tmpvn;
233 	int error;
234 	dev_t dev;
235 
236 	/*
237 	 * Lookup major number for disk block device.
238 	 */
239 	bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
240 	if (bmajor == -1)
241 		return NULL;
242 
243 	bminor = minor(device_unit(dv));
244 	/*
245 	 * Fake a temporary vnode for the disk, open it, and read
246 	 * and hash the sectors.
247 	 */
248 	dev = device_is_a(dv, "dk") ? makedev(bmajor, bminor) :
249 	    MAKEDISKDEV(bmajor, bminor, RAW_PART);
250 	if (bdevvp(dev, &tmpvn))
251 		panic("%s: can't alloc vnode for %s", __func__,
252 		    device_xname(dv));
253 	error = VOP_OPEN(tmpvn, FREAD, NOCRED);
254 	if (error) {
255 #ifndef DEBUG
256 		/*
257 		 * Ignore errors caused by missing device, partition,
258 		 * or medium.
259 		 */
260 		if (error != ENXIO && error != ENODEV)
261 #endif
262 			printf("%s: can't open dev %s (%d)\n",
263 			    __func__, device_xname(dv), error);
264 		vput(tmpvn);
265 		return NULL;
266 	}
267 
268 	return tmpvn;
269 }
270 
271 int
272 config_handle_wedges(struct device *dv, int par)
273 {
274 	struct dkwedge_list wl;
275 	struct dkwedge_info *wi;
276 	struct vnode *vn;
277 	char diskname[16];
278 	int i, error;
279 
280 	if ((vn = opendisk(dv)) == NULL)
281 		return -1;
282 
283 	wl.dkwl_bufsize = sizeof(*wi) * 16;
284 	wl.dkwl_buf = wi = malloc(wl.dkwl_bufsize, M_TEMP, M_WAITOK);
285 
286 	error = VOP_IOCTL(vn, DIOCLWEDGES, &wl, FREAD, NOCRED);
287 	VOP_CLOSE(vn, FREAD, NOCRED);
288 	vput(vn);
289 	if (error) {
290 #ifdef DEBUG_WEDGE
291 		printf("%s: List wedges returned %d\n",
292 		    device_xname(dv), error);
293 #endif
294 		free(wi, M_TEMP);
295 		return -1;
296 	}
297 
298 #ifdef DEBUG_WEDGE
299 	printf("%s: Returned %u(%u) wedges\n", device_xname(dv),
300 	    wl.dkwl_nwedges, wl.dkwl_ncopied);
301 #endif
302 	snprintf(diskname, sizeof(diskname), "%s%c", device_xname(dv),
303 	    par + 'a');
304 
305 	for (i = 0; i < wl.dkwl_ncopied; i++) {
306 #ifdef DEBUG_WEDGE
307 		printf("%s: Looking for %s in %s\n",
308 		    device_xname(dv), diskname, wi[i].dkw_wname);
309 #endif
310 		if (strcmp(wi[i].dkw_wname, diskname) == 0)
311 			break;
312 	}
313 
314 	if (i == wl.dkwl_ncopied) {
315 #ifdef DEBUG_WEDGE
316 		printf("%s: Cannot find wedge with parent %s\n",
317 		    device_xname(dv), diskname);
318 #endif
319 		free(wi, M_TEMP);
320 		return -1;
321 	}
322 
323 #ifdef DEBUG_WEDGE
324 	printf("%s: Setting boot wedge %s (%s) at %llu %llu\n",
325 		device_xname(dv), wi[i].dkw_devname, wi[i].dkw_wname,
326 		(unsigned long long)wi[i].dkw_offset,
327 		(unsigned long long)wi[i].dkw_size);
328 #endif
329 	dkwedge_set_bootwedge(dv, wi[i].dkw_offset, wi[i].dkw_size);
330 	free(wi, M_TEMP);
331 	return 0;
332 }
333 
334 /*
335  * Initialize the autoconfiguration data structures.  Normally this
336  * is done by configure(), but some platforms need to do this very
337  * early (to e.g. initialize the console).
338  */
339 void
340 config_init(void)
341 {
342 	const struct cfattachinit *cfai;
343 	int i, j;
344 
345 	if (config_initialized)
346 		return;
347 
348 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_NONE);
349 	cv_init(&alldevs_cv, "alldevs");
350 
351 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
352 	cv_init(&config_misc_cv, "cfgmisc");
353 
354 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
355 
356 	/* allcfdrivers is statically initialized. */
357 	for (i = 0; cfdriver_list_initial[i] != NULL; i++) {
358 		if (config_cfdriver_attach(cfdriver_list_initial[i]) != 0)
359 			panic("configure: duplicate `%s' drivers",
360 			    cfdriver_list_initial[i]->cd_name);
361 	}
362 
363 	for (cfai = &cfattachinit[0]; cfai->cfai_name != NULL; cfai++) {
364 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
365 			if (config_cfattach_attach(cfai->cfai_name,
366 						   cfai->cfai_list[j]) != 0)
367 				panic("configure: duplicate `%s' attachment "
368 				    "of `%s' driver",
369 				    cfai->cfai_list[j]->ca_name,
370 				    cfai->cfai_name);
371 		}
372 	}
373 
374 	initcftable.ct_cfdata = cfdata;
375 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
376 
377 	config_initialized = 1;
378 }
379 
380 void
381 config_deferred(device_t dev)
382 {
383 	config_process_deferred(&deferred_config_queue, dev);
384 	config_process_deferred(&interrupt_config_queue, dev);
385 }
386 
387 static void
388 config_interrupts_thread(void *cookie)
389 {
390 	struct deferred_config *dc;
391 
392 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
393 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
394 		(*dc->dc_func)(dc->dc_dev);
395 		kmem_free(dc, sizeof(*dc));
396 		config_pending_decr();
397 	}
398 	kthread_exit(0);
399 }
400 
401 void
402 config_create_interruptthreads()
403 {
404 	int i;
405 
406 	for (i = 0; i < interrupt_config_threads; i++) {
407 		(void)kthread_create(PRI_NONE, 0, NULL,
408 		    config_interrupts_thread, NULL, NULL, "config");
409 	}
410 }
411 
412 /*
413  * Announce device attach/detach to userland listeners.
414  */
415 static void
416 devmon_report_device(device_t dev, bool isattach)
417 {
418 #if NDRVCTL > 0
419 	prop_dictionary_t ev;
420 	const char *parent;
421 	const char *what;
422 	device_t pdev = device_parent(dev);
423 
424 	ev = prop_dictionary_create();
425 	if (ev == NULL)
426 		return;
427 
428 	what = (isattach ? "device-attach" : "device-detach");
429 	parent = (pdev == NULL ? "root" : device_xname(pdev));
430 	if (!prop_dictionary_set_cstring(ev, "device", device_xname(dev)) ||
431 	    !prop_dictionary_set_cstring(ev, "parent", parent)) {
432 		prop_object_release(ev);
433 		return;
434 	}
435 
436 	devmon_insert(what, ev);
437 #endif
438 }
439 
440 /*
441  * Add a cfdriver to the system.
442  */
443 int
444 config_cfdriver_attach(struct cfdriver *cd)
445 {
446 	struct cfdriver *lcd;
447 
448 	/* Make sure this driver isn't already in the system. */
449 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
450 		if (STREQ(lcd->cd_name, cd->cd_name))
451 			return EEXIST;
452 	}
453 
454 	LIST_INIT(&cd->cd_attach);
455 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
456 
457 	return 0;
458 }
459 
460 /*
461  * Remove a cfdriver from the system.
462  */
463 int
464 config_cfdriver_detach(struct cfdriver *cd)
465 {
466 	int i;
467 
468 	/* Make sure there are no active instances. */
469 	for (i = 0; i < cd->cd_ndevs; i++) {
470 		if (cd->cd_devs[i] != NULL)
471 			return EBUSY;
472 	}
473 
474 	/* ...and no attachments loaded. */
475 	if (LIST_EMPTY(&cd->cd_attach) == 0)
476 		return EBUSY;
477 
478 	LIST_REMOVE(cd, cd_list);
479 
480 	KASSERT(cd->cd_devs == NULL);
481 
482 	return 0;
483 }
484 
485 /*
486  * Look up a cfdriver by name.
487  */
488 struct cfdriver *
489 config_cfdriver_lookup(const char *name)
490 {
491 	struct cfdriver *cd;
492 
493 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
494 		if (STREQ(cd->cd_name, name))
495 			return cd;
496 	}
497 
498 	return NULL;
499 }
500 
501 /*
502  * Add a cfattach to the specified driver.
503  */
504 int
505 config_cfattach_attach(const char *driver, struct cfattach *ca)
506 {
507 	struct cfattach *lca;
508 	struct cfdriver *cd;
509 
510 	cd = config_cfdriver_lookup(driver);
511 	if (cd == NULL)
512 		return ESRCH;
513 
514 	/* Make sure this attachment isn't already on this driver. */
515 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
516 		if (STREQ(lca->ca_name, ca->ca_name))
517 			return EEXIST;
518 	}
519 
520 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
521 
522 	return 0;
523 }
524 
525 /*
526  * Remove a cfattach from the specified driver.
527  */
528 int
529 config_cfattach_detach(const char *driver, struct cfattach *ca)
530 {
531 	struct cfdriver *cd;
532 	device_t dev;
533 	int i;
534 
535 	cd = config_cfdriver_lookup(driver);
536 	if (cd == NULL)
537 		return ESRCH;
538 
539 	/* Make sure there are no active instances. */
540 	for (i = 0; i < cd->cd_ndevs; i++) {
541 		if ((dev = cd->cd_devs[i]) == NULL)
542 			continue;
543 		if (dev->dv_cfattach == ca)
544 			return EBUSY;
545 	}
546 
547 	LIST_REMOVE(ca, ca_list);
548 
549 	return 0;
550 }
551 
552 /*
553  * Look up a cfattach by name.
554  */
555 static struct cfattach *
556 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
557 {
558 	struct cfattach *ca;
559 
560 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
561 		if (STREQ(ca->ca_name, atname))
562 			return ca;
563 	}
564 
565 	return NULL;
566 }
567 
568 /*
569  * Look up a cfattach by driver/attachment name.
570  */
571 struct cfattach *
572 config_cfattach_lookup(const char *name, const char *atname)
573 {
574 	struct cfdriver *cd;
575 
576 	cd = config_cfdriver_lookup(name);
577 	if (cd == NULL)
578 		return NULL;
579 
580 	return config_cfattach_lookup_cd(cd, atname);
581 }
582 
583 /*
584  * Apply the matching function and choose the best.  This is used
585  * a few times and we want to keep the code small.
586  */
587 static void
588 mapply(struct matchinfo *m, cfdata_t cf)
589 {
590 	int pri;
591 
592 	if (m->fn != NULL) {
593 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
594 	} else {
595 		pri = config_match(m->parent, cf, m->aux);
596 	}
597 	if (pri > m->pri) {
598 		m->match = cf;
599 		m->pri = pri;
600 	}
601 }
602 
603 int
604 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
605 {
606 	const struct cfiattrdata *ci;
607 	const struct cflocdesc *cl;
608 	int nlocs, i;
609 
610 	ci = cfiattr_lookup(cf->cf_pspec->cfp_iattr, parent->dv_cfdriver);
611 	KASSERT(ci);
612 	nlocs = ci->ci_loclen;
613 	KASSERT(!nlocs || locs);
614 	for (i = 0; i < nlocs; i++) {
615 		cl = &ci->ci_locdesc[i];
616 		/* !cld_defaultstr means no default value */
617 		if ((!(cl->cld_defaultstr)
618 		     || (cf->cf_loc[i] != cl->cld_default))
619 		    && cf->cf_loc[i] != locs[i])
620 			return 0;
621 	}
622 
623 	return config_match(parent, cf, aux);
624 }
625 
626 /*
627  * Helper function: check whether the driver supports the interface attribute
628  * and return its descriptor structure.
629  */
630 static const struct cfiattrdata *
631 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
632 {
633 	const struct cfiattrdata * const *cpp;
634 
635 	if (cd->cd_attrs == NULL)
636 		return 0;
637 
638 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
639 		if (STREQ((*cpp)->ci_name, ia)) {
640 			/* Match. */
641 			return *cpp;
642 		}
643 	}
644 	return 0;
645 }
646 
647 /*
648  * Lookup an interface attribute description by name.
649  * If the driver is given, consider only its supported attributes.
650  */
651 const struct cfiattrdata *
652 cfiattr_lookup(const char *name, const struct cfdriver *cd)
653 {
654 	const struct cfdriver *d;
655 	const struct cfiattrdata *ia;
656 
657 	if (cd)
658 		return cfdriver_get_iattr(cd, name);
659 
660 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
661 		ia = cfdriver_get_iattr(d, name);
662 		if (ia)
663 			return ia;
664 	}
665 	return 0;
666 }
667 
668 /*
669  * Determine if `parent' is a potential parent for a device spec based
670  * on `cfp'.
671  */
672 static int
673 cfparent_match(const device_t parent, const struct cfparent *cfp)
674 {
675 	struct cfdriver *pcd;
676 
677 	/* We don't match root nodes here. */
678 	if (cfp == NULL)
679 		return 0;
680 
681 	pcd = parent->dv_cfdriver;
682 	KASSERT(pcd != NULL);
683 
684 	/*
685 	 * First, ensure this parent has the correct interface
686 	 * attribute.
687 	 */
688 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
689 		return 0;
690 
691 	/*
692 	 * If no specific parent device instance was specified (i.e.
693 	 * we're attaching to the attribute only), we're done!
694 	 */
695 	if (cfp->cfp_parent == NULL)
696 		return 1;
697 
698 	/*
699 	 * Check the parent device's name.
700 	 */
701 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
702 		return 0;	/* not the same parent */
703 
704 	/*
705 	 * Make sure the unit number matches.
706 	 */
707 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
708 	    cfp->cfp_unit == parent->dv_unit)
709 		return 1;
710 
711 	/* Unit numbers don't match. */
712 	return 0;
713 }
714 
715 /*
716  * Helper for config_cfdata_attach(): check all devices whether it could be
717  * parent any attachment in the config data table passed, and rescan.
718  */
719 static void
720 rescan_with_cfdata(const struct cfdata *cf)
721 {
722 	device_t d;
723 	const struct cfdata *cf1;
724 	deviter_t di;
725 
726 
727 	/*
728 	 * "alldevs" is likely longer than a modules's cfdata, so make it
729 	 * the outer loop.
730 	 */
731 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
732 
733 		if (!(d->dv_cfattach->ca_rescan))
734 			continue;
735 
736 		for (cf1 = cf; cf1->cf_name; cf1++) {
737 
738 			if (!cfparent_match(d, cf1->cf_pspec))
739 				continue;
740 
741 			(*d->dv_cfattach->ca_rescan)(d,
742 				cf1->cf_pspec->cfp_iattr, cf1->cf_loc);
743 		}
744 	}
745 	deviter_release(&di);
746 }
747 
748 /*
749  * Attach a supplemental config data table and rescan potential
750  * parent devices if required.
751  */
752 int
753 config_cfdata_attach(cfdata_t cf, int scannow)
754 {
755 	struct cftable *ct;
756 
757 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
758 	ct->ct_cfdata = cf;
759 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
760 
761 	if (scannow)
762 		rescan_with_cfdata(cf);
763 
764 	return 0;
765 }
766 
767 /*
768  * Helper for config_cfdata_detach: check whether a device is
769  * found through any attachment in the config data table.
770  */
771 static int
772 dev_in_cfdata(const struct device *d, const struct cfdata *cf)
773 {
774 	const struct cfdata *cf1;
775 
776 	for (cf1 = cf; cf1->cf_name; cf1++)
777 		if (d->dv_cfdata == cf1)
778 			return 1;
779 
780 	return 0;
781 }
782 
783 /*
784  * Detach a supplemental config data table. Detach all devices found
785  * through that table (and thus keeping references to it) before.
786  */
787 int
788 config_cfdata_detach(cfdata_t cf)
789 {
790 	device_t d;
791 	int error = 0;
792 	struct cftable *ct;
793 	deviter_t di;
794 
795 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
796 	     d = deviter_next(&di)) {
797 		if (!dev_in_cfdata(d, cf))
798 			continue;
799 		if ((error = config_detach(d, 0)) != 0)
800 			break;
801 	}
802 	deviter_release(&di);
803 	if (error) {
804 		aprint_error_dev(d, "unable to detach instance\n");
805 		return error;
806 	}
807 
808 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
809 		if (ct->ct_cfdata == cf) {
810 			TAILQ_REMOVE(&allcftables, ct, ct_list);
811 			kmem_free(ct, sizeof(*ct));
812 			return 0;
813 		}
814 	}
815 
816 	/* not found -- shouldn't happen */
817 	return EINVAL;
818 }
819 
820 /*
821  * Invoke the "match" routine for a cfdata entry on behalf of
822  * an external caller, usually a "submatch" routine.
823  */
824 int
825 config_match(device_t parent, cfdata_t cf, void *aux)
826 {
827 	struct cfattach *ca;
828 
829 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
830 	if (ca == NULL) {
831 		/* No attachment for this entry, oh well. */
832 		return 0;
833 	}
834 
835 	return (*ca->ca_match)(parent, cf, aux);
836 }
837 
838 /*
839  * Iterate over all potential children of some device, calling the given
840  * function (default being the child's match function) for each one.
841  * Nonzero returns are matches; the highest value returned is considered
842  * the best match.  Return the `found child' if we got a match, or NULL
843  * otherwise.  The `aux' pointer is simply passed on through.
844  *
845  * Note that this function is designed so that it can be used to apply
846  * an arbitrary function to all potential children (its return value
847  * can be ignored).
848  */
849 cfdata_t
850 config_search_loc(cfsubmatch_t fn, device_t parent,
851 		  const char *ifattr, const int *locs, void *aux)
852 {
853 	struct cftable *ct;
854 	cfdata_t cf;
855 	struct matchinfo m;
856 
857 	KASSERT(config_initialized);
858 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
859 
860 	m.fn = fn;
861 	m.parent = parent;
862 	m.locs = locs;
863 	m.aux = aux;
864 	m.match = NULL;
865 	m.pri = 0;
866 
867 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
868 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
869 
870 			/* We don't match root nodes here. */
871 			if (!cf->cf_pspec)
872 				continue;
873 
874 			/*
875 			 * Skip cf if no longer eligible, otherwise scan
876 			 * through parents for one matching `parent', and
877 			 * try match function.
878 			 */
879 			if (cf->cf_fstate == FSTATE_FOUND)
880 				continue;
881 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
882 			    cf->cf_fstate == FSTATE_DSTAR)
883 				continue;
884 
885 			/*
886 			 * If an interface attribute was specified,
887 			 * consider only children which attach to
888 			 * that attribute.
889 			 */
890 			if (ifattr && !STREQ(ifattr, cf->cf_pspec->cfp_iattr))
891 				continue;
892 
893 			if (cfparent_match(parent, cf->cf_pspec))
894 				mapply(&m, cf);
895 		}
896 	}
897 	return m.match;
898 }
899 
900 cfdata_t
901 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
902     void *aux)
903 {
904 
905 	return config_search_loc(fn, parent, ifattr, NULL, aux);
906 }
907 
908 /*
909  * Find the given root device.
910  * This is much like config_search, but there is no parent.
911  * Don't bother with multiple cfdata tables; the root node
912  * must always be in the initial table.
913  */
914 cfdata_t
915 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
916 {
917 	cfdata_t cf;
918 	const short *p;
919 	struct matchinfo m;
920 
921 	m.fn = fn;
922 	m.parent = ROOT;
923 	m.aux = aux;
924 	m.match = NULL;
925 	m.pri = 0;
926 	m.locs = 0;
927 	/*
928 	 * Look at root entries for matching name.  We do not bother
929 	 * with found-state here since only one root should ever be
930 	 * searched (and it must be done first).
931 	 */
932 	for (p = cfroots; *p >= 0; p++) {
933 		cf = &cfdata[*p];
934 		if (strcmp(cf->cf_name, rootname) == 0)
935 			mapply(&m, cf);
936 	}
937 	return m.match;
938 }
939 
940 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
941 
942 /*
943  * The given `aux' argument describes a device that has been found
944  * on the given parent, but not necessarily configured.  Locate the
945  * configuration data for that device (using the submatch function
946  * provided, or using candidates' cd_match configuration driver
947  * functions) and attach it, and return true.  If the device was
948  * not configured, call the given `print' function and return 0.
949  */
950 device_t
951 config_found_sm_loc(device_t parent,
952 		const char *ifattr, const int *locs, void *aux,
953 		cfprint_t print, cfsubmatch_t submatch)
954 {
955 	cfdata_t cf;
956 
957 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
958 	if (splash_progress_state)
959 		splash_progress_update(splash_progress_state);
960 #endif
961 
962 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
963 		return(config_attach_loc(parent, cf, locs, aux, print));
964 	if (print) {
965 		if (config_do_twiddle && cold)
966 			twiddle();
967 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
968 	}
969 
970 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
971 	if (splash_progress_state)
972 		splash_progress_update(splash_progress_state);
973 #endif
974 
975 	return NULL;
976 }
977 
978 device_t
979 config_found_ia(device_t parent, const char *ifattr, void *aux,
980     cfprint_t print)
981 {
982 
983 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
984 }
985 
986 device_t
987 config_found(device_t parent, void *aux, cfprint_t print)
988 {
989 
990 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
991 }
992 
993 /*
994  * As above, but for root devices.
995  */
996 device_t
997 config_rootfound(const char *rootname, void *aux)
998 {
999 	cfdata_t cf;
1000 
1001 	if ((cf = config_rootsearch((cfsubmatch_t)NULL, rootname, aux)) != NULL)
1002 		return config_attach(ROOT, cf, aux, (cfprint_t)NULL);
1003 	aprint_error("root device %s not configured\n", rootname);
1004 	return NULL;
1005 }
1006 
1007 /* just like sprintf(buf, "%d") except that it works from the end */
1008 static char *
1009 number(char *ep, int n)
1010 {
1011 
1012 	*--ep = 0;
1013 	while (n >= 10) {
1014 		*--ep = (n % 10) + '0';
1015 		n /= 10;
1016 	}
1017 	*--ep = n + '0';
1018 	return ep;
1019 }
1020 
1021 /*
1022  * Expand the size of the cd_devs array if necessary.
1023  */
1024 static void
1025 config_makeroom(int n, struct cfdriver *cd)
1026 {
1027 	int old, new;
1028 	device_t *nsp;
1029 
1030 	if (n < cd->cd_ndevs)
1031 		return;
1032 
1033 	/*
1034 	 * Need to expand the array.
1035 	 */
1036 	old = cd->cd_ndevs;
1037 	if (old == 0)
1038 		new = 4;
1039 	else
1040 		new = old * 2;
1041 	while (new <= n)
1042 		new *= 2;
1043 	cd->cd_ndevs = new;
1044 	nsp = kmem_alloc(sizeof(device_t [new]), KM_SLEEP);
1045 	if (nsp == NULL)
1046 		panic("config_attach: %sing dev array",
1047 		    old != 0 ? "expand" : "creat");
1048 	memset(nsp + old, 0, sizeof(device_t [new - old]));
1049 	if (old != 0) {
1050 		memcpy(nsp, cd->cd_devs, sizeof(device_t [old]));
1051 		kmem_free(cd->cd_devs, sizeof(device_t [old]));
1052 	}
1053 	cd->cd_devs = nsp;
1054 }
1055 
1056 static void
1057 config_devlink(device_t dev)
1058 {
1059 	struct cfdriver *cd = dev->dv_cfdriver;
1060 
1061 	/* put this device in the devices array */
1062 	config_makeroom(dev->dv_unit, cd);
1063 	if (cd->cd_devs[dev->dv_unit])
1064 		panic("config_attach: duplicate %s", device_xname(dev));
1065 	cd->cd_devs[dev->dv_unit] = dev;
1066 
1067 	/* It is safe to add a device to the tail of the list while
1068 	 * readers are in the list, but not while a writer is in
1069 	 * the list.  Wait for any writer to complete.
1070 	 */
1071 	mutex_enter(&alldevs_mtx);
1072 	while (alldevs_nwrite != 0 && alldevs_writer != curlwp)
1073 		cv_wait(&alldevs_cv, &alldevs_mtx);
1074 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
1075 	cv_signal(&alldevs_cv);
1076 	mutex_exit(&alldevs_mtx);
1077 }
1078 
1079 static void
1080 config_devunlink(device_t dev)
1081 {
1082 	struct cfdriver *cd = dev->dv_cfdriver;
1083 	int i;
1084 
1085 	/* Unlink from device list. */
1086 	TAILQ_REMOVE(&alldevs, dev, dv_list);
1087 
1088 	/* Remove from cfdriver's array. */
1089 	cd->cd_devs[dev->dv_unit] = NULL;
1090 
1091 	/*
1092 	 * If the device now has no units in use, deallocate its softc array.
1093 	 */
1094 	for (i = 0; i < cd->cd_ndevs; i++) {
1095 		if (cd->cd_devs[i] != NULL)
1096 			return;
1097 	}
1098 	/* nothing found; deallocate */
1099 	kmem_free(cd->cd_devs, sizeof(device_t [cd->cd_ndevs]));
1100 	cd->cd_devs = NULL;
1101 	cd->cd_ndevs = 0;
1102 }
1103 
1104 static device_t
1105 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
1106 {
1107 	struct cfdriver *cd;
1108 	struct cfattach *ca;
1109 	size_t lname, lunit;
1110 	const char *xunit;
1111 	int myunit;
1112 	char num[10];
1113 	device_t dev;
1114 	void *dev_private;
1115 	const struct cfiattrdata *ia;
1116 	device_lock_t dvl;
1117 
1118 	cd = config_cfdriver_lookup(cf->cf_name);
1119 	if (cd == NULL)
1120 		return NULL;
1121 
1122 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
1123 	if (ca == NULL)
1124 		return NULL;
1125 
1126 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
1127 	    ca->ca_devsize < sizeof(struct device))
1128 		panic("config_devalloc: %s", cf->cf_atname);
1129 
1130 #ifndef __BROKEN_CONFIG_UNIT_USAGE
1131 	if (cf->cf_fstate == FSTATE_STAR) {
1132 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
1133 			if (cd->cd_devs[myunit] == NULL)
1134 				break;
1135 		/*
1136 		 * myunit is now the unit of the first NULL device pointer,
1137 		 * or max(cd->cd_ndevs,cf->cf_unit).
1138 		 */
1139 	} else {
1140 		myunit = cf->cf_unit;
1141 		if (myunit < cd->cd_ndevs && cd->cd_devs[myunit] != NULL)
1142 			return NULL;
1143 	}
1144 #else
1145 	myunit = cf->cf_unit;
1146 #endif /* ! __BROKEN_CONFIG_UNIT_USAGE */
1147 
1148 	/* compute length of name and decimal expansion of unit number */
1149 	lname = strlen(cd->cd_name);
1150 	xunit = number(&num[sizeof(num)], myunit);
1151 	lunit = &num[sizeof(num)] - xunit;
1152 	if (lname + lunit > sizeof(dev->dv_xname))
1153 		panic("config_devalloc: device name too long");
1154 
1155 	/* get memory for all device vars */
1156 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
1157 	if (ca->ca_devsize > 0) {
1158 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
1159 		if (dev_private == NULL)
1160 			panic("config_devalloc: memory allocation for device softc failed");
1161 	} else {
1162 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
1163 		dev_private = NULL;
1164 	}
1165 
1166 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
1167 		dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
1168 	} else {
1169 		dev = dev_private;
1170 	}
1171 	if (dev == NULL)
1172 		panic("config_devalloc: memory allocation for device_t failed");
1173 
1174 	dvl = device_getlock(dev);
1175 
1176 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
1177 	cv_init(&dvl->dvl_cv, "pmfsusp");
1178 
1179 	dev->dv_class = cd->cd_class;
1180 	dev->dv_cfdata = cf;
1181 	dev->dv_cfdriver = cd;
1182 	dev->dv_cfattach = ca;
1183 	dev->dv_unit = myunit;
1184 	dev->dv_activity_count = 0;
1185 	dev->dv_activity_handlers = NULL;
1186 	dev->dv_private = dev_private;
1187 	memcpy(dev->dv_xname, cd->cd_name, lname);
1188 	memcpy(dev->dv_xname + lname, xunit, lunit);
1189 	dev->dv_parent = parent;
1190 	if (parent != NULL)
1191 		dev->dv_depth = parent->dv_depth + 1;
1192 	else
1193 		dev->dv_depth = 0;
1194 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
1195 	dev->dv_flags |= ca->ca_flags;	/* inherit flags from class */
1196 	if (locs) {
1197 		KASSERT(parent); /* no locators at root */
1198 		ia = cfiattr_lookup(cf->cf_pspec->cfp_iattr,
1199 				    parent->dv_cfdriver);
1200 		dev->dv_locators =
1201 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
1202 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
1203 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
1204 	}
1205 	dev->dv_properties = prop_dictionary_create();
1206 	KASSERT(dev->dv_properties != NULL);
1207 
1208 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
1209 	    "device-driver", dev->dv_cfdriver->cd_name);
1210 	prop_dictionary_set_uint16(dev->dv_properties,
1211 	    "device-unit", dev->dv_unit);
1212 
1213 	return dev;
1214 }
1215 
1216 static void
1217 config_devdealloc(device_t dev)
1218 {
1219 	device_lock_t dvl = device_getlock(dev);
1220 	int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
1221 
1222 	cv_destroy(&dvl->dvl_cv);
1223 	mutex_destroy(&dvl->dvl_mtx);
1224 
1225 	KASSERT(dev->dv_properties != NULL);
1226 	prop_object_release(dev->dv_properties);
1227 
1228 	if (dev->dv_activity_handlers)
1229 		panic("config_devdealloc with registered handlers");
1230 
1231 	if (dev->dv_locators) {
1232 		size_t amount = *--dev->dv_locators;
1233 		kmem_free(dev->dv_locators, amount);
1234 	}
1235 
1236 	if (dev->dv_cfattach->ca_devsize > 0)
1237 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
1238 	if (priv)
1239 		kmem_free(dev, sizeof(*dev));
1240 }
1241 
1242 /*
1243  * Attach a found device.
1244  */
1245 device_t
1246 config_attach_loc(device_t parent, cfdata_t cf,
1247 	const int *locs, void *aux, cfprint_t print)
1248 {
1249 	device_t dev;
1250 	struct cftable *ct;
1251 	const char *drvname;
1252 
1253 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1254 	if (splash_progress_state)
1255 		splash_progress_update(splash_progress_state);
1256 #endif
1257 
1258 	dev = config_devalloc(parent, cf, locs);
1259 	if (!dev)
1260 		panic("config_attach: allocation of device softc failed");
1261 
1262 	/* XXX redundant - see below? */
1263 	if (cf->cf_fstate != FSTATE_STAR) {
1264 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1265 		cf->cf_fstate = FSTATE_FOUND;
1266 	}
1267 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1268 	  else
1269 		cf->cf_unit++;
1270 #endif
1271 
1272 	config_devlink(dev);
1273 
1274 	if (config_do_twiddle && cold)
1275 		twiddle();
1276 	else
1277 		aprint_naive("Found ");
1278 	/*
1279 	 * We want the next two printfs for normal, verbose, and quiet,
1280 	 * but not silent (in which case, we're twiddling, instead).
1281 	 */
1282 	if (parent == ROOT) {
1283 		aprint_naive("%s (root)", device_xname(dev));
1284 		aprint_normal("%s (root)", device_xname(dev));
1285 	} else {
1286 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
1287 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
1288 		if (print)
1289 			(void) (*print)(aux, NULL);
1290 	}
1291 
1292 	/*
1293 	 * Before attaching, clobber any unfound devices that are
1294 	 * otherwise identical.
1295 	 * XXX code above is redundant?
1296 	 */
1297 	drvname = dev->dv_cfdriver->cd_name;
1298 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1299 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1300 			if (STREQ(cf->cf_name, drvname) &&
1301 			    cf->cf_unit == dev->dv_unit) {
1302 				if (cf->cf_fstate == FSTATE_NOTFOUND)
1303 					cf->cf_fstate = FSTATE_FOUND;
1304 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1305 				/*
1306 				 * Bump the unit number on all starred cfdata
1307 				 * entries for this device.
1308 				 */
1309 				if (cf->cf_fstate == FSTATE_STAR)
1310 					cf->cf_unit++;
1311 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1312 			}
1313 		}
1314 	}
1315 #ifdef __HAVE_DEVICE_REGISTER
1316 	device_register(dev, aux);
1317 #endif
1318 
1319 	/* Let userland know */
1320 	devmon_report_device(dev, true);
1321 
1322 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1323 	if (splash_progress_state)
1324 		splash_progress_update(splash_progress_state);
1325 #endif
1326 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
1327 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
1328 	if (splash_progress_state)
1329 		splash_progress_update(splash_progress_state);
1330 #endif
1331 
1332 	if (!device_pmf_is_registered(dev))
1333 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
1334 
1335 	config_process_deferred(&deferred_config_queue, dev);
1336 	return dev;
1337 }
1338 
1339 device_t
1340 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
1341 {
1342 
1343 	return config_attach_loc(parent, cf, NULL, aux, print);
1344 }
1345 
1346 /*
1347  * As above, but for pseudo-devices.  Pseudo-devices attached in this
1348  * way are silently inserted into the device tree, and their children
1349  * attached.
1350  *
1351  * Note that because pseudo-devices are attached silently, any information
1352  * the attach routine wishes to print should be prefixed with the device
1353  * name by the attach routine.
1354  */
1355 device_t
1356 config_attach_pseudo(cfdata_t cf)
1357 {
1358 	device_t dev;
1359 
1360 	dev = config_devalloc(ROOT, cf, NULL);
1361 	if (!dev)
1362 		return NULL;
1363 
1364 	/* XXX mark busy in cfdata */
1365 
1366 	if (cf->cf_fstate != FSTATE_STAR) {
1367 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
1368 		cf->cf_fstate = FSTATE_FOUND;
1369 	}
1370 
1371 	config_devlink(dev);
1372 
1373 #if 0	/* XXXJRT not yet */
1374 #ifdef __HAVE_DEVICE_REGISTER
1375 	device_register(dev, NULL);	/* like a root node */
1376 #endif
1377 #endif
1378 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
1379 	config_process_deferred(&deferred_config_queue, dev);
1380 	return dev;
1381 }
1382 
1383 /*
1384  * Detach a device.  Optionally forced (e.g. because of hardware
1385  * removal) and quiet.  Returns zero if successful, non-zero
1386  * (an error code) otherwise.
1387  *
1388  * Note that this code wants to be run from a process context, so
1389  * that the detach can sleep to allow processes which have a device
1390  * open to run and unwind their stacks.
1391  */
1392 int
1393 config_detach(device_t dev, int flags)
1394 {
1395 	struct cftable *ct;
1396 	cfdata_t cf;
1397 	const struct cfattach *ca;
1398 	struct cfdriver *cd;
1399 #ifdef DIAGNOSTIC
1400 	device_t d;
1401 #endif
1402 	int rv = 0;
1403 
1404 #ifdef DIAGNOSTIC
1405 	cf = dev->dv_cfdata;
1406 	if (cf != NULL && cf->cf_fstate != FSTATE_FOUND &&
1407 	    cf->cf_fstate != FSTATE_STAR)
1408 		panic("config_detach: %s: bad device fstate %d",
1409 		    device_xname(dev), cf ? cf->cf_fstate : -1);
1410 #endif
1411 	cd = dev->dv_cfdriver;
1412 	KASSERT(cd != NULL);
1413 
1414 	ca = dev->dv_cfattach;
1415 	KASSERT(ca != NULL);
1416 
1417 	KASSERT(curlwp != NULL);
1418 	mutex_enter(&alldevs_mtx);
1419 	if (alldevs_nwrite > 0 && alldevs_writer == NULL)
1420 		;
1421 	else while (alldevs_nread != 0 ||
1422 	       (alldevs_nwrite != 0 && alldevs_writer != curlwp))
1423 		cv_wait(&alldevs_cv, &alldevs_mtx);
1424 	if (alldevs_nwrite++ == 0)
1425 		alldevs_writer = curlwp;
1426 	mutex_exit(&alldevs_mtx);
1427 
1428 	/*
1429 	 * Ensure the device is deactivated.  If the device doesn't
1430 	 * have an activation entry point, we allow DVF_ACTIVE to
1431 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
1432 	 * device is busy, and the detach fails.
1433 	 */
1434 	if (!detachall &&
1435 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
1436 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
1437 		rv = EBUSY;	/* XXX EOPNOTSUPP? */
1438 	} else if ((rv = config_deactivate(dev)) == EOPNOTSUPP)
1439 		rv = 0;	/* Do not treat EOPNOTSUPP as an error */
1440 
1441 	/*
1442 	 * Try to detach the device.  If that's not possible, then
1443 	 * we either panic() (for the forced but failed case), or
1444 	 * return an error.
1445 	 */
1446 	if (rv == 0) {
1447 		if (ca->ca_detach != NULL)
1448 			rv = (*ca->ca_detach)(dev, flags);
1449 		else
1450 			rv = EOPNOTSUPP;
1451 	}
1452 	if (rv != 0) {
1453 		if ((flags & DETACH_FORCE) == 0)
1454 			goto out;
1455 		else
1456 			panic("config_detach: forced detach of %s failed (%d)",
1457 			    device_xname(dev), rv);
1458 	}
1459 
1460 	dev->dv_flags &= ~DVF_ACTIVE;
1461 
1462 	/*
1463 	 * The device has now been successfully detached.
1464 	 */
1465 
1466 	/* Let userland know */
1467 	devmon_report_device(dev, false);
1468 
1469 #ifdef DIAGNOSTIC
1470 	/*
1471 	 * Sanity: If you're successfully detached, you should have no
1472 	 * children.  (Note that because children must be attached
1473 	 * after parents, we only need to search the latter part of
1474 	 * the list.)
1475 	 */
1476 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
1477 	    d = TAILQ_NEXT(d, dv_list)) {
1478 		if (d->dv_parent == dev) {
1479 			printf("config_detach: detached device %s"
1480 			    " has children %s\n", device_xname(dev), device_xname(d));
1481 			panic("config_detach");
1482 		}
1483 	}
1484 #endif
1485 
1486 	/* notify the parent that the child is gone */
1487 	if (dev->dv_parent) {
1488 		device_t p = dev->dv_parent;
1489 		if (p->dv_cfattach->ca_childdetached)
1490 			(*p->dv_cfattach->ca_childdetached)(p, dev);
1491 	}
1492 
1493 	/*
1494 	 * Mark cfdata to show that the unit can be reused, if possible.
1495 	 */
1496 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
1497 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
1498 			if (STREQ(cf->cf_name, cd->cd_name)) {
1499 				if (cf->cf_fstate == FSTATE_FOUND &&
1500 				    cf->cf_unit == dev->dv_unit)
1501 					cf->cf_fstate = FSTATE_NOTFOUND;
1502 #ifdef __BROKEN_CONFIG_UNIT_USAGE
1503 				/*
1504 				 * Note that we can only re-use a starred
1505 				 * unit number if the unit being detached
1506 				 * had the last assigned unit number.
1507 				 */
1508 				if (cf->cf_fstate == FSTATE_STAR &&
1509 				    cf->cf_unit == dev->dv_unit + 1)
1510 					cf->cf_unit--;
1511 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
1512 			}
1513 		}
1514 	}
1515 
1516 	config_devunlink(dev);
1517 
1518 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
1519 		aprint_normal_dev(dev, "detached\n");
1520 
1521 	config_devdealloc(dev);
1522 
1523 out:
1524 	mutex_enter(&alldevs_mtx);
1525 	KASSERT(alldevs_nwrite != 0);
1526 	if (--alldevs_nwrite == 0)
1527 		alldevs_writer = NULL;
1528 	cv_signal(&alldevs_cv);
1529 	mutex_exit(&alldevs_mtx);
1530 	return rv;
1531 }
1532 
1533 int
1534 config_detach_children(device_t parent, int flags)
1535 {
1536 	device_t dv;
1537 	deviter_t di;
1538 	int error = 0;
1539 
1540 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
1541 	     dv = deviter_next(&di)) {
1542 		if (device_parent(dv) != parent)
1543 			continue;
1544 		if ((error = config_detach(dv, flags)) != 0)
1545 			break;
1546 	}
1547 	deviter_release(&di);
1548 	return error;
1549 }
1550 
1551 device_t
1552 shutdown_first(struct shutdown_state *s)
1553 {
1554 	if (!s->initialized) {
1555 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
1556 		s->initialized = true;
1557 	}
1558 	return shutdown_next(s);
1559 }
1560 
1561 device_t
1562 shutdown_next(struct shutdown_state *s)
1563 {
1564 	device_t dv;
1565 
1566 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
1567 		;
1568 
1569 	if (dv == NULL)
1570 		s->initialized = false;
1571 
1572 	return dv;
1573 }
1574 
1575 bool
1576 config_detach_all(int how)
1577 {
1578 	static struct shutdown_state s;
1579 	device_t curdev;
1580 	bool progress = false;
1581 
1582 	if ((how & RB_NOSYNC) != 0)
1583 		return false;
1584 
1585 	for (curdev = shutdown_first(&s); curdev != NULL;
1586 	     curdev = shutdown_next(&s)) {
1587 		aprint_debug(" detaching %s, ", device_xname(curdev));
1588 		if (config_detach(curdev, DETACH_SHUTDOWN) == 0) {
1589 			progress = true;
1590 			aprint_debug("success.");
1591 		} else
1592 			aprint_debug("failed.");
1593 	}
1594 	return progress;
1595 }
1596 
1597 int
1598 config_activate(device_t dev)
1599 {
1600 	const struct cfattach *ca = dev->dv_cfattach;
1601 	int rv = 0, oflags = dev->dv_flags;
1602 
1603 	if (ca->ca_activate == NULL)
1604 		return EOPNOTSUPP;
1605 
1606 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
1607 		dev->dv_flags |= DVF_ACTIVE;
1608 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
1609 		if (rv)
1610 			dev->dv_flags = oflags;
1611 	}
1612 	return rv;
1613 }
1614 
1615 int
1616 config_deactivate(device_t dev)
1617 {
1618 	const struct cfattach *ca = dev->dv_cfattach;
1619 	int rv = 0, oflags = dev->dv_flags;
1620 
1621 	if (ca->ca_activate == NULL)
1622 		return EOPNOTSUPP;
1623 
1624 	if (dev->dv_flags & DVF_ACTIVE) {
1625 		dev->dv_flags &= ~DVF_ACTIVE;
1626 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
1627 		if (rv)
1628 			dev->dv_flags = oflags;
1629 	}
1630 	return rv;
1631 }
1632 
1633 /*
1634  * Defer the configuration of the specified device until all
1635  * of its parent's devices have been attached.
1636  */
1637 void
1638 config_defer(device_t dev, void (*func)(device_t))
1639 {
1640 	struct deferred_config *dc;
1641 
1642 	if (dev->dv_parent == NULL)
1643 		panic("config_defer: can't defer config of a root device");
1644 
1645 #ifdef DIAGNOSTIC
1646 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
1647 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1648 		if (dc->dc_dev == dev)
1649 			panic("config_defer: deferred twice");
1650 	}
1651 #endif
1652 
1653 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1654 	if (dc == NULL)
1655 		panic("config_defer: unable to allocate callback");
1656 
1657 	dc->dc_dev = dev;
1658 	dc->dc_func = func;
1659 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1660 	config_pending_incr();
1661 }
1662 
1663 /*
1664  * Defer some autoconfiguration for a device until after interrupts
1665  * are enabled.
1666  */
1667 void
1668 config_interrupts(device_t dev, void (*func)(device_t))
1669 {
1670 	struct deferred_config *dc;
1671 
1672 	/*
1673 	 * If interrupts are enabled, callback now.
1674 	 */
1675 	if (cold == 0) {
1676 		(*func)(dev);
1677 		return;
1678 	}
1679 
1680 #ifdef DIAGNOSTIC
1681 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
1682 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1683 		if (dc->dc_dev == dev)
1684 			panic("config_interrupts: deferred twice");
1685 	}
1686 #endif
1687 
1688 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
1689 	if (dc == NULL)
1690 		panic("config_interrupts: unable to allocate callback");
1691 
1692 	dc->dc_dev = dev;
1693 	dc->dc_func = func;
1694 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1695 	config_pending_incr();
1696 }
1697 
1698 /*
1699  * Process a deferred configuration queue.
1700  */
1701 static void
1702 config_process_deferred(struct deferred_config_head *queue,
1703     device_t parent)
1704 {
1705 	struct deferred_config *dc, *ndc;
1706 
1707 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1708 		ndc = TAILQ_NEXT(dc, dc_queue);
1709 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1710 			TAILQ_REMOVE(queue, dc, dc_queue);
1711 			(*dc->dc_func)(dc->dc_dev);
1712 			kmem_free(dc, sizeof(*dc));
1713 			config_pending_decr();
1714 		}
1715 	}
1716 }
1717 
1718 /*
1719  * Manipulate the config_pending semaphore.
1720  */
1721 void
1722 config_pending_incr(void)
1723 {
1724 
1725 	mutex_enter(&config_misc_lock);
1726 	config_pending++;
1727 	mutex_exit(&config_misc_lock);
1728 }
1729 
1730 void
1731 config_pending_decr(void)
1732 {
1733 
1734 #ifdef DIAGNOSTIC
1735 	if (config_pending == 0)
1736 		panic("config_pending_decr: config_pending == 0");
1737 #endif
1738 	mutex_enter(&config_misc_lock);
1739 	config_pending--;
1740 	if (config_pending == 0)
1741 		cv_broadcast(&config_misc_cv);
1742 	mutex_exit(&config_misc_lock);
1743 }
1744 
1745 /*
1746  * Register a "finalization" routine.  Finalization routines are
1747  * called iteratively once all real devices have been found during
1748  * autoconfiguration, for as long as any one finalizer has done
1749  * any work.
1750  */
1751 int
1752 config_finalize_register(device_t dev, int (*fn)(device_t))
1753 {
1754 	struct finalize_hook *f;
1755 
1756 	/*
1757 	 * If finalization has already been done, invoke the
1758 	 * callback function now.
1759 	 */
1760 	if (config_finalize_done) {
1761 		while ((*fn)(dev) != 0)
1762 			/* loop */ ;
1763 	}
1764 
1765 	/* Ensure this isn't already on the list. */
1766 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1767 		if (f->f_func == fn && f->f_dev == dev)
1768 			return EEXIST;
1769 	}
1770 
1771 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
1772 	f->f_func = fn;
1773 	f->f_dev = dev;
1774 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1775 
1776 	return 0;
1777 }
1778 
1779 void
1780 config_finalize(void)
1781 {
1782 	struct finalize_hook *f;
1783 	struct pdevinit *pdev;
1784 	extern struct pdevinit pdevinit[];
1785 	int errcnt, rv;
1786 
1787 	/*
1788 	 * Now that device driver threads have been created, wait for
1789 	 * them to finish any deferred autoconfiguration.
1790 	 */
1791 	mutex_enter(&config_misc_lock);
1792 	while (config_pending != 0)
1793 		cv_wait(&config_misc_cv, &config_misc_lock);
1794 	mutex_exit(&config_misc_lock);
1795 
1796 	KERNEL_LOCK(1, NULL);
1797 
1798 	/* Attach pseudo-devices. */
1799 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
1800 		(*pdev->pdev_attach)(pdev->pdev_count);
1801 
1802 	/* Run the hooks until none of them does any work. */
1803 	do {
1804 		rv = 0;
1805 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1806 			rv |= (*f->f_func)(f->f_dev);
1807 	} while (rv != 0);
1808 
1809 	config_finalize_done = 1;
1810 
1811 	/* Now free all the hooks. */
1812 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1813 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1814 		kmem_free(f, sizeof(*f));
1815 	}
1816 
1817 	KERNEL_UNLOCK_ONE(NULL);
1818 
1819 	errcnt = aprint_get_error_count();
1820 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
1821 	    (boothowto & AB_VERBOSE) == 0) {
1822 		mutex_enter(&config_misc_lock);
1823 		if (config_do_twiddle) {
1824 			config_do_twiddle = 0;
1825 			printf_nolog(" done.\n");
1826 		}
1827 		mutex_exit(&config_misc_lock);
1828 		if (errcnt != 0) {
1829 			printf("WARNING: %d error%s while detecting hardware; "
1830 			    "check system log.\n", errcnt,
1831 			    errcnt == 1 ? "" : "s");
1832 		}
1833 	}
1834 }
1835 
1836 void
1837 config_twiddle_init()
1838 {
1839 
1840 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
1841 		config_do_twiddle = 1;
1842 	}
1843 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
1844 }
1845 
1846 void
1847 config_twiddle_fn(void *cookie)
1848 {
1849 
1850 	mutex_enter(&config_misc_lock);
1851 	if (config_do_twiddle) {
1852 		twiddle();
1853 		callout_schedule(&config_twiddle_ch, mstohz(100));
1854 	}
1855 	mutex_exit(&config_misc_lock);
1856 }
1857 
1858 /*
1859  * device_lookup:
1860  *
1861  *	Look up a device instance for a given driver.
1862  */
1863 device_t
1864 device_lookup(cfdriver_t cd, int unit)
1865 {
1866 
1867 	if (unit < 0 || unit >= cd->cd_ndevs)
1868 		return NULL;
1869 
1870 	return cd->cd_devs[unit];
1871 }
1872 
1873 /*
1874  * device_lookup:
1875  *
1876  *	Look up a device instance for a given driver.
1877  */
1878 void *
1879 device_lookup_private(cfdriver_t cd, int unit)
1880 {
1881 	device_t dv;
1882 
1883 	if (unit < 0 || unit >= cd->cd_ndevs)
1884 		return NULL;
1885 
1886 	if ((dv = cd->cd_devs[unit]) == NULL)
1887 		return NULL;
1888 
1889 	return dv->dv_private;
1890 }
1891 
1892 /*
1893  * Accessor functions for the device_t type.
1894  */
1895 devclass_t
1896 device_class(device_t dev)
1897 {
1898 
1899 	return dev->dv_class;
1900 }
1901 
1902 cfdata_t
1903 device_cfdata(device_t dev)
1904 {
1905 
1906 	return dev->dv_cfdata;
1907 }
1908 
1909 cfdriver_t
1910 device_cfdriver(device_t dev)
1911 {
1912 
1913 	return dev->dv_cfdriver;
1914 }
1915 
1916 cfattach_t
1917 device_cfattach(device_t dev)
1918 {
1919 
1920 	return dev->dv_cfattach;
1921 }
1922 
1923 int
1924 device_unit(device_t dev)
1925 {
1926 
1927 	return dev->dv_unit;
1928 }
1929 
1930 const char *
1931 device_xname(device_t dev)
1932 {
1933 
1934 	return dev->dv_xname;
1935 }
1936 
1937 device_t
1938 device_parent(device_t dev)
1939 {
1940 
1941 	return dev->dv_parent;
1942 }
1943 
1944 bool
1945 device_is_active(device_t dev)
1946 {
1947 	int active_flags;
1948 
1949 	active_flags = DVF_ACTIVE;
1950 	active_flags |= DVF_CLASS_SUSPENDED;
1951 	active_flags |= DVF_DRIVER_SUSPENDED;
1952 	active_flags |= DVF_BUS_SUSPENDED;
1953 
1954 	return (dev->dv_flags & active_flags) == DVF_ACTIVE;
1955 }
1956 
1957 bool
1958 device_is_enabled(device_t dev)
1959 {
1960 	return (dev->dv_flags & DVF_ACTIVE) == DVF_ACTIVE;
1961 }
1962 
1963 bool
1964 device_has_power(device_t dev)
1965 {
1966 	int active_flags;
1967 
1968 	active_flags = DVF_ACTIVE | DVF_BUS_SUSPENDED;
1969 
1970 	return (dev->dv_flags & active_flags) == DVF_ACTIVE;
1971 }
1972 
1973 int
1974 device_locator(device_t dev, u_int locnum)
1975 {
1976 
1977 	KASSERT(dev->dv_locators != NULL);
1978 	return dev->dv_locators[locnum];
1979 }
1980 
1981 void *
1982 device_private(device_t dev)
1983 {
1984 
1985 	/*
1986 	 * The reason why device_private(NULL) is allowed is to simplify the
1987 	 * work of a lot of userspace request handlers (i.e., c/bdev
1988 	 * handlers) which grab cfdriver_t->cd_units[n].
1989 	 * It avoids having them test for it to be NULL and only then calling
1990 	 * device_private.
1991 	 */
1992 	return dev == NULL ? NULL : dev->dv_private;
1993 }
1994 
1995 prop_dictionary_t
1996 device_properties(device_t dev)
1997 {
1998 
1999 	return dev->dv_properties;
2000 }
2001 
2002 /*
2003  * device_is_a:
2004  *
2005  *	Returns true if the device is an instance of the specified
2006  *	driver.
2007  */
2008 bool
2009 device_is_a(device_t dev, const char *dname)
2010 {
2011 
2012 	return strcmp(dev->dv_cfdriver->cd_name, dname) == 0;
2013 }
2014 
2015 /*
2016  * device_find_by_xname:
2017  *
2018  *	Returns the device of the given name or NULL if it doesn't exist.
2019  */
2020 device_t
2021 device_find_by_xname(const char *name)
2022 {
2023 	device_t dv;
2024 	deviter_t di;
2025 
2026 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
2027 		if (strcmp(device_xname(dv), name) == 0)
2028 			break;
2029 	}
2030 	deviter_release(&di);
2031 
2032 	return dv;
2033 }
2034 
2035 /*
2036  * device_find_by_driver_unit:
2037  *
2038  *	Returns the device of the given driver name and unit or
2039  *	NULL if it doesn't exist.
2040  */
2041 device_t
2042 device_find_by_driver_unit(const char *name, int unit)
2043 {
2044 	struct cfdriver *cd;
2045 
2046 	if ((cd = config_cfdriver_lookup(name)) == NULL)
2047 		return NULL;
2048 	return device_lookup(cd, unit);
2049 }
2050 
2051 /*
2052  * Power management related functions.
2053  */
2054 
2055 bool
2056 device_pmf_is_registered(device_t dev)
2057 {
2058 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
2059 }
2060 
2061 bool
2062 device_pmf_driver_suspend(device_t dev PMF_FN_ARGS)
2063 {
2064 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2065 		return true;
2066 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2067 		return false;
2068 	if (*dev->dv_driver_suspend != NULL &&
2069 	    !(*dev->dv_driver_suspend)(dev PMF_FN_CALL))
2070 		return false;
2071 
2072 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
2073 	return true;
2074 }
2075 
2076 bool
2077 device_pmf_driver_resume(device_t dev PMF_FN_ARGS)
2078 {
2079 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2080 		return true;
2081 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2082 		return false;
2083 	if ((flags & PMF_F_SELF) != 0 && !device_is_self_suspended(dev))
2084 		return false;
2085 	if (*dev->dv_driver_resume != NULL &&
2086 	    !(*dev->dv_driver_resume)(dev PMF_FN_CALL))
2087 		return false;
2088 
2089 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
2090 	return true;
2091 }
2092 
2093 bool
2094 device_pmf_driver_shutdown(device_t dev, int how)
2095 {
2096 
2097 	if (*dev->dv_driver_shutdown != NULL &&
2098 	    !(*dev->dv_driver_shutdown)(dev, how))
2099 		return false;
2100 	return true;
2101 }
2102 
2103 bool
2104 device_pmf_driver_register(device_t dev,
2105     bool (*suspend)(device_t PMF_FN_PROTO),
2106     bool (*resume)(device_t PMF_FN_PROTO),
2107     bool (*shutdown)(device_t, int))
2108 {
2109 	dev->dv_driver_suspend = suspend;
2110 	dev->dv_driver_resume = resume;
2111 	dev->dv_driver_shutdown = shutdown;
2112 	dev->dv_flags |= DVF_POWER_HANDLERS;
2113 	return true;
2114 }
2115 
2116 static const char *
2117 curlwp_name(void)
2118 {
2119 	if (curlwp->l_name != NULL)
2120 		return curlwp->l_name;
2121 	else
2122 		return curlwp->l_proc->p_comm;
2123 }
2124 
2125 void
2126 device_pmf_driver_deregister(device_t dev)
2127 {
2128 	device_lock_t dvl = device_getlock(dev);
2129 
2130 	dev->dv_driver_suspend = NULL;
2131 	dev->dv_driver_resume = NULL;
2132 
2133 	mutex_enter(&dvl->dvl_mtx);
2134 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
2135 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
2136 		/* Wake a thread that waits for the lock.  That
2137 		 * thread will fail to acquire the lock, and then
2138 		 * it will wake the next thread that waits for the
2139 		 * lock, or else it will wake us.
2140 		 */
2141 		cv_signal(&dvl->dvl_cv);
2142 		pmflock_debug(dev, __func__, __LINE__);
2143 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2144 		pmflock_debug(dev, __func__, __LINE__);
2145 	}
2146 	mutex_exit(&dvl->dvl_mtx);
2147 }
2148 
2149 bool
2150 device_pmf_driver_child_register(device_t dev)
2151 {
2152 	device_t parent = device_parent(dev);
2153 
2154 	if (parent == NULL || parent->dv_driver_child_register == NULL)
2155 		return true;
2156 	return (*parent->dv_driver_child_register)(dev);
2157 }
2158 
2159 void
2160 device_pmf_driver_set_child_register(device_t dev,
2161     bool (*child_register)(device_t))
2162 {
2163 	dev->dv_driver_child_register = child_register;
2164 }
2165 
2166 void
2167 device_pmf_self_resume(device_t dev PMF_FN_ARGS)
2168 {
2169 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2170 	if ((dev->dv_flags & DVF_SELF_SUSPENDED) != 0)
2171 		dev->dv_flags &= ~DVF_SELF_SUSPENDED;
2172 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2173 }
2174 
2175 bool
2176 device_is_self_suspended(device_t dev)
2177 {
2178 	return (dev->dv_flags & DVF_SELF_SUSPENDED) != 0;
2179 }
2180 
2181 void
2182 device_pmf_self_suspend(device_t dev PMF_FN_ARGS)
2183 {
2184 	bool self = (flags & PMF_F_SELF) != 0;
2185 
2186 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2187 
2188 	if (!self)
2189 		dev->dv_flags &= ~DVF_SELF_SUSPENDED;
2190 	else if (device_is_active(dev))
2191 		dev->dv_flags |= DVF_SELF_SUSPENDED;
2192 
2193 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2194 }
2195 
2196 static void
2197 pmflock_debug(device_t dev, const char *func, int line)
2198 {
2199 	device_lock_t dvl = device_getlock(dev);
2200 
2201 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n",
2202 	    func, line, curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait,
2203 	    dev->dv_flags);
2204 }
2205 
2206 static void
2207 pmflock_debug_with_flags(device_t dev, const char *func, int line PMF_FN_ARGS)
2208 {
2209 	device_lock_t dvl = device_getlock(dev);
2210 
2211 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x "
2212 	    "flags " PMF_FLAGS_FMT "\n", func, line, curlwp_name(),
2213 	    dvl->dvl_nlock, dvl->dvl_nwait, dev->dv_flags PMF_FN_CALL);
2214 }
2215 
2216 static bool
2217 device_pmf_lock1(device_t dev PMF_FN_ARGS)
2218 {
2219 	device_lock_t dvl = device_getlock(dev);
2220 
2221 	while (device_pmf_is_registered(dev) &&
2222 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
2223 		dvl->dvl_nwait++;
2224 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2225 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
2226 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2227 		dvl->dvl_nwait--;
2228 	}
2229 	if (!device_pmf_is_registered(dev)) {
2230 		pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2231 		/* We could not acquire the lock, but some other thread may
2232 		 * wait for it, also.  Wake that thread.
2233 		 */
2234 		cv_signal(&dvl->dvl_cv);
2235 		return false;
2236 	}
2237 	dvl->dvl_nlock++;
2238 	dvl->dvl_holder = curlwp;
2239 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2240 	return true;
2241 }
2242 
2243 bool
2244 device_pmf_lock(device_t dev PMF_FN_ARGS)
2245 {
2246 	bool rc;
2247 	device_lock_t dvl = device_getlock(dev);
2248 
2249 	mutex_enter(&dvl->dvl_mtx);
2250 	rc = device_pmf_lock1(dev PMF_FN_CALL);
2251 	mutex_exit(&dvl->dvl_mtx);
2252 
2253 	return rc;
2254 }
2255 
2256 void
2257 device_pmf_unlock(device_t dev PMF_FN_ARGS)
2258 {
2259 	device_lock_t dvl = device_getlock(dev);
2260 
2261 	KASSERT(dvl->dvl_nlock > 0);
2262 	mutex_enter(&dvl->dvl_mtx);
2263 	if (--dvl->dvl_nlock == 0)
2264 		dvl->dvl_holder = NULL;
2265 	cv_signal(&dvl->dvl_cv);
2266 	pmflock_debug_with_flags(dev, __func__, __LINE__ PMF_FN_CALL);
2267 	mutex_exit(&dvl->dvl_mtx);
2268 }
2269 
2270 device_lock_t
2271 device_getlock(device_t dev)
2272 {
2273 	return &dev->dv_lock;
2274 }
2275 
2276 void *
2277 device_pmf_bus_private(device_t dev)
2278 {
2279 	return dev->dv_bus_private;
2280 }
2281 
2282 bool
2283 device_pmf_bus_suspend(device_t dev PMF_FN_ARGS)
2284 {
2285 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
2286 		return true;
2287 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
2288 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
2289 		return false;
2290 	if (*dev->dv_bus_suspend != NULL &&
2291 	    !(*dev->dv_bus_suspend)(dev PMF_FN_CALL))
2292 		return false;
2293 
2294 	dev->dv_flags |= DVF_BUS_SUSPENDED;
2295 	return true;
2296 }
2297 
2298 bool
2299 device_pmf_bus_resume(device_t dev PMF_FN_ARGS)
2300 {
2301 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
2302 		return true;
2303 	if ((flags & PMF_F_SELF) != 0 && !device_is_self_suspended(dev))
2304 		return false;
2305 	if (*dev->dv_bus_resume != NULL &&
2306 	    !(*dev->dv_bus_resume)(dev PMF_FN_CALL))
2307 		return false;
2308 
2309 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
2310 	return true;
2311 }
2312 
2313 bool
2314 device_pmf_bus_shutdown(device_t dev, int how)
2315 {
2316 
2317 	if (*dev->dv_bus_shutdown != NULL &&
2318 	    !(*dev->dv_bus_shutdown)(dev, how))
2319 		return false;
2320 	return true;
2321 }
2322 
2323 void
2324 device_pmf_bus_register(device_t dev, void *priv,
2325     bool (*suspend)(device_t PMF_FN_PROTO),
2326     bool (*resume)(device_t PMF_FN_PROTO),
2327     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
2328 {
2329 	dev->dv_bus_private = priv;
2330 	dev->dv_bus_resume = resume;
2331 	dev->dv_bus_suspend = suspend;
2332 	dev->dv_bus_shutdown = shutdown;
2333 	dev->dv_bus_deregister = deregister;
2334 }
2335 
2336 void
2337 device_pmf_bus_deregister(device_t dev)
2338 {
2339 	if (dev->dv_bus_deregister == NULL)
2340 		return;
2341 	(*dev->dv_bus_deregister)(dev);
2342 	dev->dv_bus_private = NULL;
2343 	dev->dv_bus_suspend = NULL;
2344 	dev->dv_bus_resume = NULL;
2345 	dev->dv_bus_deregister = NULL;
2346 }
2347 
2348 void *
2349 device_pmf_class_private(device_t dev)
2350 {
2351 	return dev->dv_class_private;
2352 }
2353 
2354 bool
2355 device_pmf_class_suspend(device_t dev PMF_FN_ARGS)
2356 {
2357 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
2358 		return true;
2359 	if (*dev->dv_class_suspend != NULL &&
2360 	    !(*dev->dv_class_suspend)(dev PMF_FN_CALL))
2361 		return false;
2362 
2363 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
2364 	return true;
2365 }
2366 
2367 bool
2368 device_pmf_class_resume(device_t dev PMF_FN_ARGS)
2369 {
2370 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
2371 		return true;
2372 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
2373 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
2374 		return false;
2375 	if (*dev->dv_class_resume != NULL &&
2376 	    !(*dev->dv_class_resume)(dev PMF_FN_CALL))
2377 		return false;
2378 
2379 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
2380 	return true;
2381 }
2382 
2383 void
2384 device_pmf_class_register(device_t dev, void *priv,
2385     bool (*suspend)(device_t PMF_FN_PROTO),
2386     bool (*resume)(device_t PMF_FN_PROTO),
2387     void (*deregister)(device_t))
2388 {
2389 	dev->dv_class_private = priv;
2390 	dev->dv_class_suspend = suspend;
2391 	dev->dv_class_resume = resume;
2392 	dev->dv_class_deregister = deregister;
2393 }
2394 
2395 void
2396 device_pmf_class_deregister(device_t dev)
2397 {
2398 	if (dev->dv_class_deregister == NULL)
2399 		return;
2400 	(*dev->dv_class_deregister)(dev);
2401 	dev->dv_class_private = NULL;
2402 	dev->dv_class_suspend = NULL;
2403 	dev->dv_class_resume = NULL;
2404 	dev->dv_class_deregister = NULL;
2405 }
2406 
2407 bool
2408 device_active(device_t dev, devactive_t type)
2409 {
2410 	size_t i;
2411 
2412 	if (dev->dv_activity_count == 0)
2413 		return false;
2414 
2415 	for (i = 0; i < dev->dv_activity_count; ++i) {
2416 		if (dev->dv_activity_handlers[i] == NULL)
2417 			break;
2418 		(*dev->dv_activity_handlers[i])(dev, type);
2419 	}
2420 
2421 	return true;
2422 }
2423 
2424 bool
2425 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
2426 {
2427 	void (**new_handlers)(device_t, devactive_t);
2428 	void (**old_handlers)(device_t, devactive_t);
2429 	size_t i, old_size, new_size;
2430 	int s;
2431 
2432 	old_handlers = dev->dv_activity_handlers;
2433 	old_size = dev->dv_activity_count;
2434 
2435 	for (i = 0; i < old_size; ++i) {
2436 		KASSERT(old_handlers[i] != handler);
2437 		if (old_handlers[i] == NULL) {
2438 			old_handlers[i] = handler;
2439 			return true;
2440 		}
2441 	}
2442 
2443 	new_size = old_size + 4;
2444 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
2445 
2446 	memcpy(new_handlers, old_handlers, sizeof(void *[old_size]));
2447 	new_handlers[old_size] = handler;
2448 	memset(new_handlers + old_size + 1, 0,
2449 	    sizeof(int [new_size - (old_size+1)]));
2450 
2451 	s = splhigh();
2452 	dev->dv_activity_count = new_size;
2453 	dev->dv_activity_handlers = new_handlers;
2454 	splx(s);
2455 
2456 	if (old_handlers != NULL)
2457 		kmem_free(old_handlers, sizeof(void * [old_size]));
2458 
2459 	return true;
2460 }
2461 
2462 void
2463 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
2464 {
2465 	void (**old_handlers)(device_t, devactive_t);
2466 	size_t i, old_size;
2467 	int s;
2468 
2469 	old_handlers = dev->dv_activity_handlers;
2470 	old_size = dev->dv_activity_count;
2471 
2472 	for (i = 0; i < old_size; ++i) {
2473 		if (old_handlers[i] == handler)
2474 			break;
2475 		if (old_handlers[i] == NULL)
2476 			return; /* XXX panic? */
2477 	}
2478 
2479 	if (i == old_size)
2480 		return; /* XXX panic? */
2481 
2482 	for (; i < old_size - 1; ++i) {
2483 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
2484 			continue;
2485 
2486 		if (i == 0) {
2487 			s = splhigh();
2488 			dev->dv_activity_count = 0;
2489 			dev->dv_activity_handlers = NULL;
2490 			splx(s);
2491 			kmem_free(old_handlers, sizeof(void *[old_size]));
2492 		}
2493 		return;
2494 	}
2495 	old_handlers[i] = NULL;
2496 }
2497 
2498 /*
2499  * Device Iteration
2500  *
2501  * deviter_t: a device iterator.  Holds state for a "walk" visiting
2502  *     each device_t's in the device tree.
2503  *
2504  * deviter_init(di, flags): initialize the device iterator `di'
2505  *     to "walk" the device tree.  deviter_next(di) will return
2506  *     the first device_t in the device tree, or NULL if there are
2507  *     no devices.
2508  *
2509  *     `flags' is one or more of DEVITER_F_RW, indicating that the
2510  *     caller intends to modify the device tree by calling
2511  *     config_detach(9) on devices in the order that the iterator
2512  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
2513  *     nearest the "root" of the device tree to be returned, first;
2514  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
2515  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
2516  *     indicating both that deviter_init() should not respect any
2517  *     locks on the device tree, and that deviter_next(di) may run
2518  *     in more than one LWP before the walk has finished.
2519  *
2520  *     Only one DEVITER_F_RW iterator may be in the device tree at
2521  *     once.
2522  *
2523  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
2524  *
2525  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
2526  *     DEVITER_F_LEAVES_FIRST are used in combination.
2527  *
2528  * deviter_first(di, flags): initialize the device iterator `di'
2529  *     and return the first device_t in the device tree, or NULL
2530  *     if there are no devices.  The statement
2531  *
2532  *         dv = deviter_first(di);
2533  *
2534  *     is shorthand for
2535  *
2536  *         deviter_init(di);
2537  *         dv = deviter_next(di);
2538  *
2539  * deviter_next(di): return the next device_t in the device tree,
2540  *     or NULL if there are no more devices.  deviter_next(di)
2541  *     is undefined if `di' was not initialized with deviter_init() or
2542  *     deviter_first().
2543  *
2544  * deviter_release(di): stops iteration (subsequent calls to
2545  *     deviter_next() will return NULL), releases any locks and
2546  *     resources held by the device iterator.
2547  *
2548  * Device iteration does not return device_t's in any particular
2549  * order.  An iterator will never return the same device_t twice.
2550  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
2551  * is called repeatedly on the same `di', it will eventually return
2552  * NULL.  It is ok to attach/detach devices during device iteration.
2553  */
2554 void
2555 deviter_init(deviter_t *di, deviter_flags_t flags)
2556 {
2557 	device_t dv;
2558 	bool rw;
2559 
2560 	mutex_enter(&alldevs_mtx);
2561 	if ((flags & DEVITER_F_SHUTDOWN) != 0) {
2562 		flags |= DEVITER_F_RW;
2563 		alldevs_nwrite++;
2564 		alldevs_writer = NULL;
2565 		alldevs_nread = 0;
2566 	} else {
2567 		rw = (flags & DEVITER_F_RW) != 0;
2568 
2569 		if (alldevs_nwrite > 0 && alldevs_writer == NULL)
2570 			;
2571 		else while ((alldevs_nwrite != 0 && alldevs_writer != curlwp) ||
2572 		       (rw && alldevs_nread != 0))
2573 			cv_wait(&alldevs_cv, &alldevs_mtx);
2574 
2575 		if (rw) {
2576 			if (alldevs_nwrite++ == 0)
2577 				alldevs_writer = curlwp;
2578 		} else
2579 			alldevs_nread++;
2580 	}
2581 	mutex_exit(&alldevs_mtx);
2582 
2583 	memset(di, 0, sizeof(*di));
2584 
2585 	di->di_flags = flags;
2586 
2587 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2588 	case DEVITER_F_LEAVES_FIRST:
2589 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2590 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
2591 		break;
2592 	case DEVITER_F_ROOT_FIRST:
2593 		TAILQ_FOREACH(dv, &alldevs, dv_list)
2594 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
2595 		break;
2596 	default:
2597 		break;
2598 	}
2599 
2600 	deviter_reinit(di);
2601 }
2602 
2603 static void
2604 deviter_reinit(deviter_t *di)
2605 {
2606 	if ((di->di_flags & DEVITER_F_RW) != 0)
2607 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
2608 	else
2609 		di->di_prev = TAILQ_FIRST(&alldevs);
2610 }
2611 
2612 device_t
2613 deviter_first(deviter_t *di, deviter_flags_t flags)
2614 {
2615 	deviter_init(di, flags);
2616 	return deviter_next(di);
2617 }
2618 
2619 static device_t
2620 deviter_next1(deviter_t *di)
2621 {
2622 	device_t dv;
2623 
2624 	dv = di->di_prev;
2625 
2626 	if (dv == NULL)
2627 		;
2628 	else if ((di->di_flags & DEVITER_F_RW) != 0)
2629 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
2630 	else
2631 		di->di_prev = TAILQ_NEXT(dv, dv_list);
2632 
2633 	return dv;
2634 }
2635 
2636 device_t
2637 deviter_next(deviter_t *di)
2638 {
2639 	device_t dv = NULL;
2640 
2641 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
2642 	case 0:
2643 		return deviter_next1(di);
2644 	case DEVITER_F_LEAVES_FIRST:
2645 		while (di->di_curdepth >= 0) {
2646 			if ((dv = deviter_next1(di)) == NULL) {
2647 				di->di_curdepth--;
2648 				deviter_reinit(di);
2649 			} else if (dv->dv_depth == di->di_curdepth)
2650 				break;
2651 		}
2652 		return dv;
2653 	case DEVITER_F_ROOT_FIRST:
2654 		while (di->di_curdepth <= di->di_maxdepth) {
2655 			if ((dv = deviter_next1(di)) == NULL) {
2656 				di->di_curdepth++;
2657 				deviter_reinit(di);
2658 			} else if (dv->dv_depth == di->di_curdepth)
2659 				break;
2660 		}
2661 		return dv;
2662 	default:
2663 		return NULL;
2664 	}
2665 }
2666 
2667 void
2668 deviter_release(deviter_t *di)
2669 {
2670 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
2671 
2672 	mutex_enter(&alldevs_mtx);
2673 	if (!rw) {
2674 		--alldevs_nread;
2675 		cv_signal(&alldevs_cv);
2676 	} else if (alldevs_nwrite > 0 && alldevs_writer == NULL) {
2677 		--alldevs_nwrite;	/* shutting down: do not signal */
2678 	} else {
2679 		KASSERT(alldevs_nwrite != 0);
2680 		if (--alldevs_nwrite == 0)
2681 			alldevs_writer = NULL;
2682 		cv_signal(&alldevs_cv);
2683 	}
2684 	mutex_exit(&alldevs_mtx);
2685 }
2686 
2687 SYSCTL_SETUP(sysctl_detach_setup, "sysctl detach setup")
2688 {
2689 	const struct sysctlnode *node = NULL;
2690 
2691 	sysctl_createv(clog, 0, NULL, &node,
2692 		CTLFLAG_PERMANENT,
2693 		CTLTYPE_NODE, "kern", NULL,
2694 		NULL, 0, NULL, 0,
2695 		CTL_KERN, CTL_EOL);
2696 
2697 	if (node == NULL)
2698 		return;
2699 
2700 	sysctl_createv(clog, 0, &node, NULL,
2701 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
2702 		CTLTYPE_INT, "detachall",
2703 		SYSCTL_DESCR("Detach all devices at shutdown"),
2704 		NULL, 0, &detachall, 0,
2705 		CTL_CREATE, CTL_EOL);
2706 }
2707