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subr_autoconf.c revision 1.203.2.1
      1 /* $NetBSD: subr_autoconf.c,v 1.203.2.1 2010/05/30 05:17:57 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 1.203.2.1 2010/05/30 05:17:57 rmind Exp $");
     81 
     82 #ifdef _KERNEL_OPT
     83 #include "opt_ddb.h"
     84 #endif
     85 
     86 #include <sys/param.h>
     87 #include <sys/device.h>
     88 #include <sys/disklabel.h>
     89 #include <sys/conf.h>
     90 #include <sys/kauth.h>
     91 #include <sys/malloc.h>
     92 #include <sys/kmem.h>
     93 #include <sys/systm.h>
     94 #include <sys/kernel.h>
     95 #include <sys/errno.h>
     96 #include <sys/proc.h>
     97 #include <sys/reboot.h>
     98 #include <sys/kthread.h>
     99 #include <sys/buf.h>
    100 #include <sys/dirent.h>
    101 #include <sys/vnode.h>
    102 #include <sys/mount.h>
    103 #include <sys/namei.h>
    104 #include <sys/unistd.h>
    105 #include <sys/fcntl.h>
    106 #include <sys/lockf.h>
    107 #include <sys/callout.h>
    108 #include <sys/devmon.h>
    109 #include <sys/cpu.h>
    110 #include <sys/sysctl.h>
    111 
    112 #include <sys/disk.h>
    113 
    114 #include <machine/limits.h>
    115 
    116 #if defined(__i386__) && defined(_KERNEL_OPT)
    117 #include "opt_splash.h"
    118 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
    119 #include <dev/splash/splash.h>
    120 extern struct splash_progress *splash_progress_state;
    121 #endif
    122 #endif
    123 
    124 /*
    125  * Autoconfiguration subroutines.
    126  */
    127 
    128 /*
    129  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
    130  * devices and drivers are found via these tables.
    131  */
    132 extern struct cfdata cfdata[];
    133 extern const short cfroots[];
    134 
    135 /*
    136  * List of all cfdriver structures.  We use this to detect duplicates
    137  * when other cfdrivers are loaded.
    138  */
    139 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
    140 extern struct cfdriver * const cfdriver_list_initial[];
    141 
    142 /*
    143  * Initial list of cfattach's.
    144  */
    145 extern const struct cfattachinit cfattachinit[];
    146 
    147 /*
    148  * List of cfdata tables.  We always have one such list -- the one
    149  * built statically when the kernel was configured.
    150  */
    151 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
    152 static struct cftable initcftable;
    153 
    154 #define	ROOT ((device_t)NULL)
    155 
    156 struct matchinfo {
    157 	cfsubmatch_t fn;
    158 	struct	device *parent;
    159 	const int *locs;
    160 	void	*aux;
    161 	struct	cfdata *match;
    162 	int	pri;
    163 };
    164 
    165 struct alldevs_foray {
    166 	int			af_s;
    167 	struct devicelist	af_garbage;
    168 };
    169 
    170 static char *number(char *, int);
    171 static void mapply(struct matchinfo *, cfdata_t);
    172 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
    173 static void config_devdelete(device_t);
    174 static void config_devunlink(device_t, struct devicelist *);
    175 static void config_makeroom(int, struct cfdriver *);
    176 static void config_devlink(device_t);
    177 static void config_alldevs_unlock(int);
    178 static int config_alldevs_lock(void);
    179 static void config_alldevs_enter(struct alldevs_foray *);
    180 static void config_alldevs_exit(struct alldevs_foray *);
    181 
    182 static void config_collect_garbage(struct devicelist *);
    183 static void config_dump_garbage(struct devicelist *);
    184 
    185 static void pmflock_debug(device_t, const char *, int);
    186 
    187 static device_t deviter_next1(deviter_t *);
    188 static void deviter_reinit(deviter_t *);
    189 
    190 struct deferred_config {
    191 	TAILQ_ENTRY(deferred_config) dc_queue;
    192 	device_t dc_dev;
    193 	void (*dc_func)(device_t);
    194 };
    195 
    196 TAILQ_HEAD(deferred_config_head, deferred_config);
    197 
    198 struct deferred_config_head deferred_config_queue =
    199 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
    200 struct deferred_config_head interrupt_config_queue =
    201 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
    202 int interrupt_config_threads = 8;
    203 
    204 static void config_process_deferred(struct deferred_config_head *, device_t);
    205 
    206 /* Hooks to finalize configuration once all real devices have been found. */
    207 struct finalize_hook {
    208 	TAILQ_ENTRY(finalize_hook) f_list;
    209 	int (*f_func)(device_t);
    210 	device_t f_dev;
    211 };
    212 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
    213 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
    214 static int config_finalize_done;
    215 
    216 /* list of all devices */
    217 static struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
    218 static kmutex_t alldevs_mtx;
    219 static volatile bool alldevs_garbage = false;
    220 static volatile devgen_t alldevs_gen = 1;
    221 static volatile int alldevs_nread = 0;
    222 static volatile int alldevs_nwrite = 0;
    223 
    224 static int config_pending;		/* semaphore for mountroot */
    225 static kmutex_t config_misc_lock;
    226 static kcondvar_t config_misc_cv;
    227 
    228 static int detachall = 0;
    229 
    230 #define	STREQ(s1, s2)			\
    231 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
    232 
    233 static bool config_initialized = false;	/* config_init() has been called. */
    234 
    235 static int config_do_twiddle;
    236 static callout_t config_twiddle_ch;
    237 
    238 static void sysctl_detach_setup(struct sysctllog **);
    239 
    240 typedef int (*cfdriver_fn)(struct cfdriver *);
    241 static int
    242 frob_cfdrivervec(struct cfdriver * const *cfdriverv,
    243 	cfdriver_fn drv_do, cfdriver_fn drv_undo,
    244 	const char *style, bool dopanic)
    245 {
    246 	void (*pr)(const char *, ...) = dopanic ? panic : printf;
    247 	int i = 0, error = 0, e2;
    248 
    249 	for (i = 0; cfdriverv[i] != NULL; i++) {
    250 		if ((error = drv_do(cfdriverv[i])) != 0) {
    251 			pr("configure: `%s' driver %s failed: %d",
    252 			    cfdriverv[i]->cd_name, style, error);
    253 			goto bad;
    254 		}
    255 	}
    256 
    257 	KASSERT(error == 0);
    258 	return 0;
    259 
    260  bad:
    261 	printf("\n");
    262 	for (i--; i >= 0; i--) {
    263 		e2 = drv_undo(cfdriverv[i]);
    264 		KASSERT(e2 == 0);
    265 	}
    266 
    267 	return error;
    268 }
    269 
    270 typedef int (*cfattach_fn)(const char *, struct cfattach *);
    271 static int
    272 frob_cfattachvec(const struct cfattachinit *cfattachv,
    273 	cfattach_fn att_do, cfattach_fn att_undo,
    274 	const char *style, bool dopanic)
    275 {
    276 	const struct cfattachinit *cfai = NULL;
    277 	void (*pr)(const char *, ...) = dopanic ? panic : printf;
    278 	int j = 0, error = 0, e2;
    279 
    280 	for (cfai = &cfattachv[0]; cfai->cfai_name != NULL; cfai++) {
    281 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
    282 			if ((error = att_do(cfai->cfai_name,
    283 			    cfai->cfai_list[j]) != 0)) {
    284 				pr("configure: attachment `%s' "
    285 				    "of `%s' driver %s failed: %d",
    286 				    cfai->cfai_list[j]->ca_name,
    287 				    cfai->cfai_name, style, error);
    288 				goto bad;
    289 			}
    290 		}
    291 	}
    292 
    293 	KASSERT(error == 0);
    294 	return 0;
    295 
    296  bad:
    297 	/*
    298 	 * Rollback in reverse order.  dunno if super-important, but
    299 	 * do that anyway.  Although the code looks a little like
    300 	 * someone did a little integration (in the math sense).
    301 	 */
    302 	printf("\n");
    303 	if (cfai) {
    304 		bool last;
    305 
    306 		for (last = false; last == false; ) {
    307 			if (cfai == &cfattachv[0])
    308 				last = true;
    309 			for (j--; j >= 0; j--) {
    310 				e2 = att_undo(cfai->cfai_name,
    311 				    cfai->cfai_list[j]);
    312 				KASSERT(e2 == 0);
    313 			}
    314 			if (!last) {
    315 				cfai--;
    316 				for (j = 0; cfai->cfai_list[j] != NULL; j++)
    317 					;
    318 			}
    319 		}
    320 	}
    321 
    322 	return error;
    323 }
    324 
    325 /*
    326  * Initialize the autoconfiguration data structures.  Normally this
    327  * is done by configure(), but some platforms need to do this very
    328  * early (to e.g. initialize the console).
    329  */
    330 void
    331 config_init(void)
    332 {
    333 
    334 	KASSERT(config_initialized == false);
    335 
    336 	mutex_init(&alldevs_mtx, MUTEX_DEFAULT, IPL_VM);
    337 
    338 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
    339 	cv_init(&config_misc_cv, "cfgmisc");
    340 
    341 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
    342 
    343 	frob_cfdrivervec(cfdriver_list_initial,
    344 	    config_cfdriver_attach, NULL, "bootstrap", true);
    345 	frob_cfattachvec(cfattachinit,
    346 	    config_cfattach_attach, NULL, "bootstrap", true);
    347 
    348 	initcftable.ct_cfdata = cfdata;
    349 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
    350 
    351 	config_initialized = true;
    352 }
    353 
    354 /*
    355  * Init or fini drivers and attachments.  Either all or none
    356  * are processed (via rollback).  It would be nice if this were
    357  * atomic to outside consumers, but with the current state of
    358  * locking ...
    359  */
    360 int
    361 config_init_component(struct cfdriver * const *cfdriverv,
    362 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
    363 {
    364 	int error;
    365 
    366 	if ((error = frob_cfdrivervec(cfdriverv,
    367 	    config_cfdriver_attach, config_cfdriver_detach, "init", false))!= 0)
    368 		return error;
    369 	if ((error = frob_cfattachvec(cfattachv,
    370 	    config_cfattach_attach, config_cfattach_detach,
    371 	    "init", false)) != 0) {
    372 		frob_cfdrivervec(cfdriverv,
    373 	            config_cfdriver_detach, NULL, "init rollback", true);
    374 		return error;
    375 	}
    376 	if ((error = config_cfdata_attach(cfdatav, 1)) != 0) {
    377 		frob_cfattachvec(cfattachv,
    378 		    config_cfattach_detach, NULL, "init rollback", true);
    379 		frob_cfdrivervec(cfdriverv,
    380 	            config_cfdriver_detach, NULL, "init rollback", true);
    381 		return error;
    382 	}
    383 
    384 	return 0;
    385 }
    386 
    387 int
    388 config_fini_component(struct cfdriver * const *cfdriverv,
    389 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
    390 {
    391 	int error;
    392 
    393 	if ((error = config_cfdata_detach(cfdatav)) != 0)
    394 		return error;
    395 	if ((error = frob_cfattachvec(cfattachv,
    396 	    config_cfattach_detach, config_cfattach_attach,
    397 	    "fini", false)) != 0) {
    398 		if (config_cfdata_attach(cfdatav, 0) != 0)
    399 			panic("config_cfdata fini rollback failed");
    400 		return error;
    401 	}
    402 	if ((error = frob_cfdrivervec(cfdriverv,
    403 	    config_cfdriver_detach, config_cfdriver_attach,
    404 	    "fini", false)) != 0) {
    405 		frob_cfattachvec(cfattachv,
    406 	            config_cfattach_attach, NULL, "fini rollback", true);
    407 		if (config_cfdata_attach(cfdatav, 0) != 0)
    408 			panic("config_cfdata fini rollback failed");
    409 		return error;
    410 	}
    411 
    412 	return 0;
    413 }
    414 
    415 void
    416 config_init_mi(void)
    417 {
    418 
    419 	if (!config_initialized)
    420 		config_init();
    421 
    422 	sysctl_detach_setup(NULL);
    423 }
    424 
    425 void
    426 config_deferred(device_t dev)
    427 {
    428 	config_process_deferred(&deferred_config_queue, dev);
    429 	config_process_deferred(&interrupt_config_queue, dev);
    430 }
    431 
    432 static void
    433 config_interrupts_thread(void *cookie)
    434 {
    435 	struct deferred_config *dc;
    436 
    437 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
    438 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
    439 		(*dc->dc_func)(dc->dc_dev);
    440 		kmem_free(dc, sizeof(*dc));
    441 		config_pending_decr();
    442 	}
    443 	kthread_exit(0);
    444 }
    445 
    446 void
    447 config_create_interruptthreads()
    448 {
    449 	int i;
    450 
    451 	for (i = 0; i < interrupt_config_threads; i++) {
    452 		(void)kthread_create(PRI_NONE, 0, NULL,
    453 		    config_interrupts_thread, NULL, NULL, "config");
    454 	}
    455 }
    456 
    457 /*
    458  * Announce device attach/detach to userland listeners.
    459  */
    460 static void
    461 devmon_report_device(device_t dev, bool isattach)
    462 {
    463 #if NDRVCTL > 0
    464 	prop_dictionary_t ev;
    465 	const char *parent;
    466 	const char *what;
    467 	device_t pdev = device_parent(dev);
    468 
    469 	ev = prop_dictionary_create();
    470 	if (ev == NULL)
    471 		return;
    472 
    473 	what = (isattach ? "device-attach" : "device-detach");
    474 	parent = (pdev == NULL ? "root" : device_xname(pdev));
    475 	if (!prop_dictionary_set_cstring(ev, "device", device_xname(dev)) ||
    476 	    !prop_dictionary_set_cstring(ev, "parent", parent)) {
    477 		prop_object_release(ev);
    478 		return;
    479 	}
    480 
    481 	devmon_insert(what, ev);
    482 #endif
    483 }
    484 
    485 /*
    486  * Add a cfdriver to the system.
    487  */
    488 int
    489 config_cfdriver_attach(struct cfdriver *cd)
    490 {
    491 	struct cfdriver *lcd;
    492 
    493 	/* Make sure this driver isn't already in the system. */
    494 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
    495 		if (STREQ(lcd->cd_name, cd->cd_name))
    496 			return EEXIST;
    497 	}
    498 
    499 	LIST_INIT(&cd->cd_attach);
    500 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
    501 
    502 	return 0;
    503 }
    504 
    505 /*
    506  * Remove a cfdriver from the system.
    507  */
    508 int
    509 config_cfdriver_detach(struct cfdriver *cd)
    510 {
    511 	struct alldevs_foray af;
    512 	int i, rc = 0;
    513 
    514 	config_alldevs_enter(&af);
    515 	/* Make sure there are no active instances. */
    516 	for (i = 0; i < cd->cd_ndevs; i++) {
    517 		if (cd->cd_devs[i] != NULL) {
    518 			rc = EBUSY;
    519 			break;
    520 		}
    521 	}
    522 	config_alldevs_exit(&af);
    523 
    524 	if (rc != 0)
    525 		return rc;
    526 
    527 	/* ...and no attachments loaded. */
    528 	if (LIST_EMPTY(&cd->cd_attach) == 0)
    529 		return EBUSY;
    530 
    531 	LIST_REMOVE(cd, cd_list);
    532 
    533 	KASSERT(cd->cd_devs == NULL);
    534 
    535 	return 0;
    536 }
    537 
    538 /*
    539  * Look up a cfdriver by name.
    540  */
    541 struct cfdriver *
    542 config_cfdriver_lookup(const char *name)
    543 {
    544 	struct cfdriver *cd;
    545 
    546 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
    547 		if (STREQ(cd->cd_name, name))
    548 			return cd;
    549 	}
    550 
    551 	return NULL;
    552 }
    553 
    554 /*
    555  * Add a cfattach to the specified driver.
    556  */
    557 int
    558 config_cfattach_attach(const char *driver, struct cfattach *ca)
    559 {
    560 	struct cfattach *lca;
    561 	struct cfdriver *cd;
    562 
    563 	cd = config_cfdriver_lookup(driver);
    564 	if (cd == NULL)
    565 		return ESRCH;
    566 
    567 	/* Make sure this attachment isn't already on this driver. */
    568 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
    569 		if (STREQ(lca->ca_name, ca->ca_name))
    570 			return EEXIST;
    571 	}
    572 
    573 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
    574 
    575 	return 0;
    576 }
    577 
    578 /*
    579  * Remove a cfattach from the specified driver.
    580  */
    581 int
    582 config_cfattach_detach(const char *driver, struct cfattach *ca)
    583 {
    584 	struct alldevs_foray af;
    585 	struct cfdriver *cd;
    586 	device_t dev;
    587 	int i, rc = 0;
    588 
    589 	cd = config_cfdriver_lookup(driver);
    590 	if (cd == NULL)
    591 		return ESRCH;
    592 
    593 	config_alldevs_enter(&af);
    594 	/* Make sure there are no active instances. */
    595 	for (i = 0; i < cd->cd_ndevs; i++) {
    596 		if ((dev = cd->cd_devs[i]) == NULL)
    597 			continue;
    598 		if (dev->dv_cfattach == ca) {
    599 			rc = EBUSY;
    600 			break;
    601 		}
    602 	}
    603 	config_alldevs_exit(&af);
    604 
    605 	if (rc != 0)
    606 		return rc;
    607 
    608 	LIST_REMOVE(ca, ca_list);
    609 
    610 	return 0;
    611 }
    612 
    613 /*
    614  * Look up a cfattach by name.
    615  */
    616 static struct cfattach *
    617 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
    618 {
    619 	struct cfattach *ca;
    620 
    621 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
    622 		if (STREQ(ca->ca_name, atname))
    623 			return ca;
    624 	}
    625 
    626 	return NULL;
    627 }
    628 
    629 /*
    630  * Look up a cfattach by driver/attachment name.
    631  */
    632 struct cfattach *
    633 config_cfattach_lookup(const char *name, const char *atname)
    634 {
    635 	struct cfdriver *cd;
    636 
    637 	cd = config_cfdriver_lookup(name);
    638 	if (cd == NULL)
    639 		return NULL;
    640 
    641 	return config_cfattach_lookup_cd(cd, atname);
    642 }
    643 
    644 /*
    645  * Apply the matching function and choose the best.  This is used
    646  * a few times and we want to keep the code small.
    647  */
    648 static void
    649 mapply(struct matchinfo *m, cfdata_t cf)
    650 {
    651 	int pri;
    652 
    653 	if (m->fn != NULL) {
    654 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
    655 	} else {
    656 		pri = config_match(m->parent, cf, m->aux);
    657 	}
    658 	if (pri > m->pri) {
    659 		m->match = cf;
    660 		m->pri = pri;
    661 	}
    662 }
    663 
    664 int
    665 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
    666 {
    667 	const struct cfiattrdata *ci;
    668 	const struct cflocdesc *cl;
    669 	int nlocs, i;
    670 
    671 	ci = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
    672 	KASSERT(ci);
    673 	nlocs = ci->ci_loclen;
    674 	KASSERT(!nlocs || locs);
    675 	for (i = 0; i < nlocs; i++) {
    676 		cl = &ci->ci_locdesc[i];
    677 		/* !cld_defaultstr means no default value */
    678 		if ((!(cl->cld_defaultstr)
    679 		     || (cf->cf_loc[i] != cl->cld_default))
    680 		    && cf->cf_loc[i] != locs[i])
    681 			return 0;
    682 	}
    683 
    684 	return config_match(parent, cf, aux);
    685 }
    686 
    687 /*
    688  * Helper function: check whether the driver supports the interface attribute
    689  * and return its descriptor structure.
    690  */
    691 static const struct cfiattrdata *
    692 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
    693 {
    694 	const struct cfiattrdata * const *cpp;
    695 
    696 	if (cd->cd_attrs == NULL)
    697 		return 0;
    698 
    699 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
    700 		if (STREQ((*cpp)->ci_name, ia)) {
    701 			/* Match. */
    702 			return *cpp;
    703 		}
    704 	}
    705 	return 0;
    706 }
    707 
    708 /*
    709  * Lookup an interface attribute description by name.
    710  * If the driver is given, consider only its supported attributes.
    711  */
    712 const struct cfiattrdata *
    713 cfiattr_lookup(const char *name, const struct cfdriver *cd)
    714 {
    715 	const struct cfdriver *d;
    716 	const struct cfiattrdata *ia;
    717 
    718 	if (cd)
    719 		return cfdriver_get_iattr(cd, name);
    720 
    721 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
    722 		ia = cfdriver_get_iattr(d, name);
    723 		if (ia)
    724 			return ia;
    725 	}
    726 	return 0;
    727 }
    728 
    729 /*
    730  * Determine if `parent' is a potential parent for a device spec based
    731  * on `cfp'.
    732  */
    733 static int
    734 cfparent_match(const device_t parent, const struct cfparent *cfp)
    735 {
    736 	struct cfdriver *pcd;
    737 
    738 	/* We don't match root nodes here. */
    739 	if (cfp == NULL)
    740 		return 0;
    741 
    742 	pcd = parent->dv_cfdriver;
    743 	KASSERT(pcd != NULL);
    744 
    745 	/*
    746 	 * First, ensure this parent has the correct interface
    747 	 * attribute.
    748 	 */
    749 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
    750 		return 0;
    751 
    752 	/*
    753 	 * If no specific parent device instance was specified (i.e.
    754 	 * we're attaching to the attribute only), we're done!
    755 	 */
    756 	if (cfp->cfp_parent == NULL)
    757 		return 1;
    758 
    759 	/*
    760 	 * Check the parent device's name.
    761 	 */
    762 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
    763 		return 0;	/* not the same parent */
    764 
    765 	/*
    766 	 * Make sure the unit number matches.
    767 	 */
    768 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
    769 	    cfp->cfp_unit == parent->dv_unit)
    770 		return 1;
    771 
    772 	/* Unit numbers don't match. */
    773 	return 0;
    774 }
    775 
    776 /*
    777  * Helper for config_cfdata_attach(): check all devices whether it could be
    778  * parent any attachment in the config data table passed, and rescan.
    779  */
    780 static void
    781 rescan_with_cfdata(const struct cfdata *cf)
    782 {
    783 	device_t d;
    784 	const struct cfdata *cf1;
    785 	deviter_t di;
    786 
    787 
    788 	/*
    789 	 * "alldevs" is likely longer than a modules's cfdata, so make it
    790 	 * the outer loop.
    791 	 */
    792 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
    793 
    794 		if (!(d->dv_cfattach->ca_rescan))
    795 			continue;
    796 
    797 		for (cf1 = cf; cf1->cf_name; cf1++) {
    798 
    799 			if (!cfparent_match(d, cf1->cf_pspec))
    800 				continue;
    801 
    802 			(*d->dv_cfattach->ca_rescan)(d,
    803 				cfdata_ifattr(cf1), cf1->cf_loc);
    804 		}
    805 	}
    806 	deviter_release(&di);
    807 }
    808 
    809 /*
    810  * Attach a supplemental config data table and rescan potential
    811  * parent devices if required.
    812  */
    813 int
    814 config_cfdata_attach(cfdata_t cf, int scannow)
    815 {
    816 	struct cftable *ct;
    817 
    818 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
    819 	ct->ct_cfdata = cf;
    820 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
    821 
    822 	if (scannow)
    823 		rescan_with_cfdata(cf);
    824 
    825 	return 0;
    826 }
    827 
    828 /*
    829  * Helper for config_cfdata_detach: check whether a device is
    830  * found through any attachment in the config data table.
    831  */
    832 static int
    833 dev_in_cfdata(const struct device *d, const struct cfdata *cf)
    834 {
    835 	const struct cfdata *cf1;
    836 
    837 	for (cf1 = cf; cf1->cf_name; cf1++)
    838 		if (d->dv_cfdata == cf1)
    839 			return 1;
    840 
    841 	return 0;
    842 }
    843 
    844 /*
    845  * Detach a supplemental config data table. Detach all devices found
    846  * through that table (and thus keeping references to it) before.
    847  */
    848 int
    849 config_cfdata_detach(cfdata_t cf)
    850 {
    851 	device_t d;
    852 	int error = 0;
    853 	struct cftable *ct;
    854 	deviter_t di;
    855 
    856 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
    857 	     d = deviter_next(&di)) {
    858 		if (!dev_in_cfdata(d, cf))
    859 			continue;
    860 		if ((error = config_detach(d, 0)) != 0)
    861 			break;
    862 	}
    863 	deviter_release(&di);
    864 	if (error) {
    865 		aprint_error_dev(d, "unable to detach instance\n");
    866 		return error;
    867 	}
    868 
    869 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
    870 		if (ct->ct_cfdata == cf) {
    871 			TAILQ_REMOVE(&allcftables, ct, ct_list);
    872 			kmem_free(ct, sizeof(*ct));
    873 			return 0;
    874 		}
    875 	}
    876 
    877 	/* not found -- shouldn't happen */
    878 	return EINVAL;
    879 }
    880 
    881 /*
    882  * Invoke the "match" routine for a cfdata entry on behalf of
    883  * an external caller, usually a "submatch" routine.
    884  */
    885 int
    886 config_match(device_t parent, cfdata_t cf, void *aux)
    887 {
    888 	struct cfattach *ca;
    889 
    890 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
    891 	if (ca == NULL) {
    892 		/* No attachment for this entry, oh well. */
    893 		return 0;
    894 	}
    895 
    896 	return (*ca->ca_match)(parent, cf, aux);
    897 }
    898 
    899 /*
    900  * Iterate over all potential children of some device, calling the given
    901  * function (default being the child's match function) for each one.
    902  * Nonzero returns are matches; the highest value returned is considered
    903  * the best match.  Return the `found child' if we got a match, or NULL
    904  * otherwise.  The `aux' pointer is simply passed on through.
    905  *
    906  * Note that this function is designed so that it can be used to apply
    907  * an arbitrary function to all potential children (its return value
    908  * can be ignored).
    909  */
    910 cfdata_t
    911 config_search_loc(cfsubmatch_t fn, device_t parent,
    912 		  const char *ifattr, const int *locs, void *aux)
    913 {
    914 	struct cftable *ct;
    915 	cfdata_t cf;
    916 	struct matchinfo m;
    917 
    918 	KASSERT(config_initialized);
    919 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
    920 
    921 	m.fn = fn;
    922 	m.parent = parent;
    923 	m.locs = locs;
    924 	m.aux = aux;
    925 	m.match = NULL;
    926 	m.pri = 0;
    927 
    928 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
    929 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
    930 
    931 			/* We don't match root nodes here. */
    932 			if (!cf->cf_pspec)
    933 				continue;
    934 
    935 			/*
    936 			 * Skip cf if no longer eligible, otherwise scan
    937 			 * through parents for one matching `parent', and
    938 			 * try match function.
    939 			 */
    940 			if (cf->cf_fstate == FSTATE_FOUND)
    941 				continue;
    942 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
    943 			    cf->cf_fstate == FSTATE_DSTAR)
    944 				continue;
    945 
    946 			/*
    947 			 * If an interface attribute was specified,
    948 			 * consider only children which attach to
    949 			 * that attribute.
    950 			 */
    951 			if (ifattr && !STREQ(ifattr, cfdata_ifattr(cf)))
    952 				continue;
    953 
    954 			if (cfparent_match(parent, cf->cf_pspec))
    955 				mapply(&m, cf);
    956 		}
    957 	}
    958 	return m.match;
    959 }
    960 
    961 cfdata_t
    962 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
    963     void *aux)
    964 {
    965 
    966 	return config_search_loc(fn, parent, ifattr, NULL, aux);
    967 }
    968 
    969 /*
    970  * Find the given root device.
    971  * This is much like config_search, but there is no parent.
    972  * Don't bother with multiple cfdata tables; the root node
    973  * must always be in the initial table.
    974  */
    975 cfdata_t
    976 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
    977 {
    978 	cfdata_t cf;
    979 	const short *p;
    980 	struct matchinfo m;
    981 
    982 	m.fn = fn;
    983 	m.parent = ROOT;
    984 	m.aux = aux;
    985 	m.match = NULL;
    986 	m.pri = 0;
    987 	m.locs = 0;
    988 	/*
    989 	 * Look at root entries for matching name.  We do not bother
    990 	 * with found-state here since only one root should ever be
    991 	 * searched (and it must be done first).
    992 	 */
    993 	for (p = cfroots; *p >= 0; p++) {
    994 		cf = &cfdata[*p];
    995 		if (strcmp(cf->cf_name, rootname) == 0)
    996 			mapply(&m, cf);
    997 	}
    998 	return m.match;
    999 }
   1000 
   1001 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
   1002 
   1003 /*
   1004  * The given `aux' argument describes a device that has been found
   1005  * on the given parent, but not necessarily configured.  Locate the
   1006  * configuration data for that device (using the submatch function
   1007  * provided, or using candidates' cd_match configuration driver
   1008  * functions) and attach it, and return true.  If the device was
   1009  * not configured, call the given `print' function and return 0.
   1010  */
   1011 device_t
   1012 config_found_sm_loc(device_t parent,
   1013 		const char *ifattr, const int *locs, void *aux,
   1014 		cfprint_t print, cfsubmatch_t submatch)
   1015 {
   1016 	cfdata_t cf;
   1017 
   1018 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
   1019 	if (splash_progress_state)
   1020 		splash_progress_update(splash_progress_state);
   1021 #endif
   1022 
   1023 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
   1024 		return(config_attach_loc(parent, cf, locs, aux, print));
   1025 	if (print) {
   1026 		if (config_do_twiddle && cold)
   1027 			twiddle();
   1028 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
   1029 	}
   1030 
   1031 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
   1032 	if (splash_progress_state)
   1033 		splash_progress_update(splash_progress_state);
   1034 #endif
   1035 
   1036 	return NULL;
   1037 }
   1038 
   1039 device_t
   1040 config_found_ia(device_t parent, const char *ifattr, void *aux,
   1041     cfprint_t print)
   1042 {
   1043 
   1044 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
   1045 }
   1046 
   1047 device_t
   1048 config_found(device_t parent, void *aux, cfprint_t print)
   1049 {
   1050 
   1051 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
   1052 }
   1053 
   1054 /*
   1055  * As above, but for root devices.
   1056  */
   1057 device_t
   1058 config_rootfound(const char *rootname, void *aux)
   1059 {
   1060 	cfdata_t cf;
   1061 
   1062 	if ((cf = config_rootsearch((cfsubmatch_t)NULL, rootname, aux)) != NULL)
   1063 		return config_attach(ROOT, cf, aux, (cfprint_t)NULL);
   1064 	aprint_error("root device %s not configured\n", rootname);
   1065 	return NULL;
   1066 }
   1067 
   1068 /* just like sprintf(buf, "%d") except that it works from the end */
   1069 static char *
   1070 number(char *ep, int n)
   1071 {
   1072 
   1073 	*--ep = 0;
   1074 	while (n >= 10) {
   1075 		*--ep = (n % 10) + '0';
   1076 		n /= 10;
   1077 	}
   1078 	*--ep = n + '0';
   1079 	return ep;
   1080 }
   1081 
   1082 /*
   1083  * Expand the size of the cd_devs array if necessary.
   1084  *
   1085  * The caller must hold alldevs_mtx. config_makeroom() may release and
   1086  * re-acquire alldevs_mtx, so callers should re-check conditions such
   1087  * as alldevs_nwrite == 0 and alldevs_nread == 0 when config_makeroom()
   1088  * returns.
   1089  */
   1090 static void
   1091 config_makeroom(int n, struct cfdriver *cd)
   1092 {
   1093 	int old, new;
   1094 	device_t *osp, *nsp;
   1095 
   1096 	alldevs_nwrite++;
   1097 
   1098 	for (new = MAX(4, cd->cd_ndevs); new <= n; new += new)
   1099 		;
   1100 
   1101 	while (n >= cd->cd_ndevs) {
   1102 		/*
   1103 		 * Need to expand the array.
   1104 		 */
   1105 		old = cd->cd_ndevs;
   1106 		osp = cd->cd_devs;
   1107 
   1108 		/* Release alldevs_mtx around allocation, which may
   1109 		 * sleep.
   1110 		 */
   1111 		mutex_exit(&alldevs_mtx);
   1112 		nsp = kmem_alloc(sizeof(device_t[new]), KM_SLEEP);
   1113 		if (nsp == NULL)
   1114 			panic("%s: could not expand cd_devs", __func__);
   1115 		mutex_enter(&alldevs_mtx);
   1116 
   1117 		/* If another thread moved the array while we did
   1118 		 * not hold alldevs_mtx, try again.
   1119 		 */
   1120 		if (cd->cd_devs != osp) {
   1121 			mutex_exit(&alldevs_mtx);
   1122 			kmem_free(nsp, sizeof(device_t[new]));
   1123 			mutex_enter(&alldevs_mtx);
   1124 			continue;
   1125 		}
   1126 
   1127 		memset(nsp + old, 0, sizeof(device_t[new - old]));
   1128 		if (old != 0)
   1129 			memcpy(nsp, cd->cd_devs, sizeof(device_t[old]));
   1130 
   1131 		cd->cd_ndevs = new;
   1132 		cd->cd_devs = nsp;
   1133 		if (old != 0) {
   1134 			mutex_exit(&alldevs_mtx);
   1135 			kmem_free(osp, sizeof(device_t[old]));
   1136 			mutex_enter(&alldevs_mtx);
   1137 		}
   1138 	}
   1139 	alldevs_nwrite--;
   1140 }
   1141 
   1142 /*
   1143  * Put dev into the devices list.
   1144  */
   1145 static void
   1146 config_devlink(device_t dev)
   1147 {
   1148 	int s;
   1149 
   1150 	s = config_alldevs_lock();
   1151 
   1152 	KASSERT(device_cfdriver(dev)->cd_devs[dev->dv_unit] == dev);
   1153 
   1154 	dev->dv_add_gen = alldevs_gen;
   1155 	/* It is safe to add a device to the tail of the list while
   1156 	 * readers and writers are in the list.
   1157 	 */
   1158 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);
   1159 	config_alldevs_unlock(s);
   1160 }
   1161 
   1162 static void
   1163 config_devfree(device_t dev)
   1164 {
   1165 	int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
   1166 
   1167 	if (dev->dv_cfattach->ca_devsize > 0)
   1168 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
   1169 	if (priv)
   1170 		kmem_free(dev, sizeof(*dev));
   1171 }
   1172 
   1173 /*
   1174  * Caller must hold alldevs_mtx.
   1175  */
   1176 static void
   1177 config_devunlink(device_t dev, struct devicelist *garbage)
   1178 {
   1179 	struct device_garbage *dg = &dev->dv_garbage;
   1180 	cfdriver_t cd = device_cfdriver(dev);
   1181 	int i;
   1182 
   1183 	KASSERT(mutex_owned(&alldevs_mtx));
   1184 
   1185  	/* Unlink from device list.  Link to garbage list. */
   1186 	TAILQ_REMOVE(&alldevs, dev, dv_list);
   1187 	TAILQ_INSERT_TAIL(garbage, dev, dv_list);
   1188 
   1189 	/* Remove from cfdriver's array. */
   1190 	cd->cd_devs[dev->dv_unit] = NULL;
   1191 
   1192 	/*
   1193 	 * If the device now has no units in use, unlink its softc array.
   1194 	 */
   1195 	for (i = 0; i < cd->cd_ndevs; i++) {
   1196 		if (cd->cd_devs[i] != NULL)
   1197 			break;
   1198 	}
   1199 	/* Nothing found.  Unlink, now.  Deallocate, later. */
   1200 	if (i == cd->cd_ndevs) {
   1201 		dg->dg_ndevs = cd->cd_ndevs;
   1202 		dg->dg_devs = cd->cd_devs;
   1203 		cd->cd_devs = NULL;
   1204 		cd->cd_ndevs = 0;
   1205 	}
   1206 }
   1207 
   1208 static void
   1209 config_devdelete(device_t dev)
   1210 {
   1211 	struct device_garbage *dg = &dev->dv_garbage;
   1212 	device_lock_t dvl = device_getlock(dev);
   1213 
   1214 	if (dg->dg_devs != NULL)
   1215 		kmem_free(dg->dg_devs, sizeof(device_t[dg->dg_ndevs]));
   1216 
   1217 	cv_destroy(&dvl->dvl_cv);
   1218 	mutex_destroy(&dvl->dvl_mtx);
   1219 
   1220 	KASSERT(dev->dv_properties != NULL);
   1221 	prop_object_release(dev->dv_properties);
   1222 
   1223 	if (dev->dv_activity_handlers)
   1224 		panic("%s with registered handlers", __func__);
   1225 
   1226 	if (dev->dv_locators) {
   1227 		size_t amount = *--dev->dv_locators;
   1228 		kmem_free(dev->dv_locators, amount);
   1229 	}
   1230 
   1231 	config_devfree(dev);
   1232 }
   1233 
   1234 static int
   1235 config_unit_nextfree(cfdriver_t cd, cfdata_t cf)
   1236 {
   1237 	int unit;
   1238 
   1239 	if (cf->cf_fstate == FSTATE_STAR) {
   1240 		for (unit = cf->cf_unit; unit < cd->cd_ndevs; unit++)
   1241 			if (cd->cd_devs[unit] == NULL)
   1242 				break;
   1243 		/*
   1244 		 * unit is now the unit of the first NULL device pointer,
   1245 		 * or max(cd->cd_ndevs,cf->cf_unit).
   1246 		 */
   1247 	} else {
   1248 		unit = cf->cf_unit;
   1249 		if (unit < cd->cd_ndevs && cd->cd_devs[unit] != NULL)
   1250 			unit = -1;
   1251 	}
   1252 	return unit;
   1253 }
   1254 
   1255 static int
   1256 config_unit_alloc(device_t dev, cfdriver_t cd, cfdata_t cf)
   1257 {
   1258 	struct alldevs_foray af;
   1259 	int unit;
   1260 
   1261 	config_alldevs_enter(&af);
   1262 	for (;;) {
   1263 		unit = config_unit_nextfree(cd, cf);
   1264 		if (unit == -1)
   1265 			break;
   1266 		if (unit < cd->cd_ndevs) {
   1267 			cd->cd_devs[unit] = dev;
   1268 			dev->dv_unit = unit;
   1269 			break;
   1270 		}
   1271 		config_makeroom(unit, cd);
   1272 	}
   1273 	config_alldevs_exit(&af);
   1274 
   1275 	return unit;
   1276 }
   1277 
   1278 static device_t
   1279 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
   1280 {
   1281 	cfdriver_t cd;
   1282 	cfattach_t ca;
   1283 	size_t lname, lunit;
   1284 	const char *xunit;
   1285 	int myunit;
   1286 	char num[10];
   1287 	device_t dev;
   1288 	void *dev_private;
   1289 	const struct cfiattrdata *ia;
   1290 	device_lock_t dvl;
   1291 
   1292 	cd = config_cfdriver_lookup(cf->cf_name);
   1293 	if (cd == NULL)
   1294 		return NULL;
   1295 
   1296 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
   1297 	if (ca == NULL)
   1298 		return NULL;
   1299 
   1300 	if ((ca->ca_flags & DVF_PRIV_ALLOC) == 0 &&
   1301 	    ca->ca_devsize < sizeof(struct device))
   1302 		panic("config_devalloc: %s", cf->cf_atname);
   1303 
   1304 	/* get memory for all device vars */
   1305 	KASSERT((ca->ca_flags & DVF_PRIV_ALLOC) || ca->ca_devsize >= sizeof(struct device));
   1306 	if (ca->ca_devsize > 0) {
   1307 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
   1308 		if (dev_private == NULL)
   1309 			panic("config_devalloc: memory allocation for device softc failed");
   1310 	} else {
   1311 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
   1312 		dev_private = NULL;
   1313 	}
   1314 
   1315 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
   1316 		dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
   1317 	} else {
   1318 		dev = dev_private;
   1319 	}
   1320 	if (dev == NULL)
   1321 		panic("config_devalloc: memory allocation for device_t failed");
   1322 
   1323 	dev->dv_class = cd->cd_class;
   1324 	dev->dv_cfdata = cf;
   1325 	dev->dv_cfdriver = cd;
   1326 	dev->dv_cfattach = ca;
   1327 	dev->dv_activity_count = 0;
   1328 	dev->dv_activity_handlers = NULL;
   1329 	dev->dv_private = dev_private;
   1330 	dev->dv_flags = ca->ca_flags;	/* inherit flags from class */
   1331 
   1332 	myunit = config_unit_alloc(dev, cd, cf);
   1333 	if (myunit == -1) {
   1334 		config_devfree(dev);
   1335 		return NULL;
   1336 	}
   1337 
   1338 	/* compute length of name and decimal expansion of unit number */
   1339 	lname = strlen(cd->cd_name);
   1340 	xunit = number(&num[sizeof(num)], myunit);
   1341 	lunit = &num[sizeof(num)] - xunit;
   1342 	if (lname + lunit > sizeof(dev->dv_xname))
   1343 		panic("config_devalloc: device name too long");
   1344 
   1345 	dvl = device_getlock(dev);
   1346 
   1347 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
   1348 	cv_init(&dvl->dvl_cv, "pmfsusp");
   1349 
   1350 	memcpy(dev->dv_xname, cd->cd_name, lname);
   1351 	memcpy(dev->dv_xname + lname, xunit, lunit);
   1352 	dev->dv_parent = parent;
   1353 	if (parent != NULL)
   1354 		dev->dv_depth = parent->dv_depth + 1;
   1355 	else
   1356 		dev->dv_depth = 0;
   1357 	dev->dv_flags |= DVF_ACTIVE;	/* always initially active */
   1358 	if (locs) {
   1359 		KASSERT(parent); /* no locators at root */
   1360 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
   1361 		dev->dv_locators =
   1362 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
   1363 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
   1364 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
   1365 	}
   1366 	dev->dv_properties = prop_dictionary_create();
   1367 	KASSERT(dev->dv_properties != NULL);
   1368 
   1369 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
   1370 	    "device-driver", dev->dv_cfdriver->cd_name);
   1371 	prop_dictionary_set_uint16(dev->dv_properties,
   1372 	    "device-unit", dev->dv_unit);
   1373 
   1374 	return dev;
   1375 }
   1376 
   1377 /*
   1378  * Attach a found device.
   1379  */
   1380 device_t
   1381 config_attach_loc(device_t parent, cfdata_t cf,
   1382 	const int *locs, void *aux, cfprint_t print)
   1383 {
   1384 	device_t dev;
   1385 	struct cftable *ct;
   1386 	const char *drvname;
   1387 
   1388 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
   1389 	if (splash_progress_state)
   1390 		splash_progress_update(splash_progress_state);
   1391 #endif
   1392 
   1393 	dev = config_devalloc(parent, cf, locs);
   1394 	if (!dev)
   1395 		panic("config_attach: allocation of device softc failed");
   1396 
   1397 	/* XXX redundant - see below? */
   1398 	if (cf->cf_fstate != FSTATE_STAR) {
   1399 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
   1400 		cf->cf_fstate = FSTATE_FOUND;
   1401 	}
   1402 
   1403 	config_devlink(dev);
   1404 
   1405 	if (config_do_twiddle && cold)
   1406 		twiddle();
   1407 	else
   1408 		aprint_naive("Found ");
   1409 	/*
   1410 	 * We want the next two printfs for normal, verbose, and quiet,
   1411 	 * but not silent (in which case, we're twiddling, instead).
   1412 	 */
   1413 	if (parent == ROOT) {
   1414 		aprint_naive("%s (root)", device_xname(dev));
   1415 		aprint_normal("%s (root)", device_xname(dev));
   1416 	} else {
   1417 		aprint_naive("%s at %s", device_xname(dev), device_xname(parent));
   1418 		aprint_normal("%s at %s", device_xname(dev), device_xname(parent));
   1419 		if (print)
   1420 			(void) (*print)(aux, NULL);
   1421 	}
   1422 
   1423 	/*
   1424 	 * Before attaching, clobber any unfound devices that are
   1425 	 * otherwise identical.
   1426 	 * XXX code above is redundant?
   1427 	 */
   1428 	drvname = dev->dv_cfdriver->cd_name;
   1429 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
   1430 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
   1431 			if (STREQ(cf->cf_name, drvname) &&
   1432 			    cf->cf_unit == dev->dv_unit) {
   1433 				if (cf->cf_fstate == FSTATE_NOTFOUND)
   1434 					cf->cf_fstate = FSTATE_FOUND;
   1435 			}
   1436 		}
   1437 	}
   1438 #ifdef __HAVE_DEVICE_REGISTER
   1439 	device_register(dev, aux);
   1440 #endif
   1441 
   1442 	/* Let userland know */
   1443 	devmon_report_device(dev, true);
   1444 
   1445 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
   1446 	if (splash_progress_state)
   1447 		splash_progress_update(splash_progress_state);
   1448 #endif
   1449 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
   1450 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_PROGRESS)
   1451 	if (splash_progress_state)
   1452 		splash_progress_update(splash_progress_state);
   1453 #endif
   1454 
   1455 	if (!device_pmf_is_registered(dev))
   1456 		aprint_debug_dev(dev, "WARNING: power management not supported\n");
   1457 
   1458 	config_process_deferred(&deferred_config_queue, dev);
   1459 
   1460 #ifdef __HAVE_DEVICE_REGISTER_POSTCONFIG
   1461 	device_register_post_config(dev, aux);
   1462 #endif
   1463 	return dev;
   1464 }
   1465 
   1466 device_t
   1467 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
   1468 {
   1469 
   1470 	return config_attach_loc(parent, cf, NULL, aux, print);
   1471 }
   1472 
   1473 /*
   1474  * As above, but for pseudo-devices.  Pseudo-devices attached in this
   1475  * way are silently inserted into the device tree, and their children
   1476  * attached.
   1477  *
   1478  * Note that because pseudo-devices are attached silently, any information
   1479  * the attach routine wishes to print should be prefixed with the device
   1480  * name by the attach routine.
   1481  */
   1482 device_t
   1483 config_attach_pseudo(cfdata_t cf)
   1484 {
   1485 	device_t dev;
   1486 
   1487 	dev = config_devalloc(ROOT, cf, NULL);
   1488 	if (!dev)
   1489 		return NULL;
   1490 
   1491 	/* XXX mark busy in cfdata */
   1492 
   1493 	if (cf->cf_fstate != FSTATE_STAR) {
   1494 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
   1495 		cf->cf_fstate = FSTATE_FOUND;
   1496 	}
   1497 
   1498 	config_devlink(dev);
   1499 
   1500 #if 0	/* XXXJRT not yet */
   1501 #ifdef __HAVE_DEVICE_REGISTER
   1502 	device_register(dev, NULL);	/* like a root node */
   1503 #endif
   1504 #endif
   1505 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
   1506 	config_process_deferred(&deferred_config_queue, dev);
   1507 	return dev;
   1508 }
   1509 
   1510 /*
   1511  * Caller must hold alldevs_mtx.
   1512  */
   1513 static void
   1514 config_collect_garbage(struct devicelist *garbage)
   1515 {
   1516 	device_t dv;
   1517 
   1518 	KASSERT(!cpu_intr_p());
   1519 	KASSERT(!cpu_softintr_p());
   1520 	KASSERT(mutex_owned(&alldevs_mtx));
   1521 
   1522 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
   1523 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   1524 			if (dv->dv_del_gen != 0)
   1525 				break;
   1526 		}
   1527 		if (dv == NULL) {
   1528 			alldevs_garbage = false;
   1529 			break;
   1530 		}
   1531 		config_devunlink(dv, garbage);
   1532 	}
   1533 	KASSERT(mutex_owned(&alldevs_mtx));
   1534 }
   1535 
   1536 static void
   1537 config_dump_garbage(struct devicelist *garbage)
   1538 {
   1539 	device_t dv;
   1540 
   1541 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
   1542 		TAILQ_REMOVE(garbage, dv, dv_list);
   1543 		config_devdelete(dv);
   1544 	}
   1545 }
   1546 
   1547 /*
   1548  * Detach a device.  Optionally forced (e.g. because of hardware
   1549  * removal) and quiet.  Returns zero if successful, non-zero
   1550  * (an error code) otherwise.
   1551  *
   1552  * Note that this code wants to be run from a process context, so
   1553  * that the detach can sleep to allow processes which have a device
   1554  * open to run and unwind their stacks.
   1555  */
   1556 int
   1557 config_detach(device_t dev, int flags)
   1558 {
   1559 	struct alldevs_foray af;
   1560 	struct cftable *ct;
   1561 	cfdata_t cf;
   1562 	const struct cfattach *ca;
   1563 	struct cfdriver *cd;
   1564 #ifdef DIAGNOSTIC
   1565 	device_t d;
   1566 #endif
   1567 	int rv = 0, s;
   1568 
   1569 #ifdef DIAGNOSTIC
   1570 	cf = dev->dv_cfdata;
   1571 	if (cf != NULL && cf->cf_fstate != FSTATE_FOUND &&
   1572 	    cf->cf_fstate != FSTATE_STAR)
   1573 		panic("config_detach: %s: bad device fstate %d",
   1574 		    device_xname(dev), cf ? cf->cf_fstate : -1);
   1575 #endif
   1576 	cd = dev->dv_cfdriver;
   1577 	KASSERT(cd != NULL);
   1578 
   1579 	ca = dev->dv_cfattach;
   1580 	KASSERT(ca != NULL);
   1581 
   1582 	s = config_alldevs_lock();
   1583 	if (dev->dv_del_gen != 0) {
   1584 		config_alldevs_unlock(s);
   1585 #ifdef DIAGNOSTIC
   1586 		printf("%s: %s is already detached\n", __func__,
   1587 		    device_xname(dev));
   1588 #endif /* DIAGNOSTIC */
   1589 		return ENOENT;
   1590 	}
   1591 	alldevs_nwrite++;
   1592 	config_alldevs_unlock(s);
   1593 
   1594 	if (!detachall &&
   1595 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
   1596 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
   1597 		rv = EOPNOTSUPP;
   1598 	} else if (ca->ca_detach != NULL) {
   1599 		rv = (*ca->ca_detach)(dev, flags);
   1600 	} else
   1601 		rv = EOPNOTSUPP;
   1602 
   1603 	/*
   1604 	 * If it was not possible to detach the device, then we either
   1605 	 * panic() (for the forced but failed case), or return an error.
   1606 	 *
   1607 	 * If it was possible to detach the device, ensure that the
   1608 	 * device is deactivated.
   1609 	 */
   1610 	if (rv == 0)
   1611 		dev->dv_flags &= ~DVF_ACTIVE;
   1612 	else if ((flags & DETACH_FORCE) == 0)
   1613 		goto out;
   1614 	else {
   1615 		panic("config_detach: forced detach of %s failed (%d)",
   1616 		    device_xname(dev), rv);
   1617 	}
   1618 
   1619 	/*
   1620 	 * The device has now been successfully detached.
   1621 	 */
   1622 
   1623 	/* Let userland know */
   1624 	devmon_report_device(dev, false);
   1625 
   1626 #ifdef DIAGNOSTIC
   1627 	/*
   1628 	 * Sanity: If you're successfully detached, you should have no
   1629 	 * children.  (Note that because children must be attached
   1630 	 * after parents, we only need to search the latter part of
   1631 	 * the list.)
   1632 	 */
   1633 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
   1634 	    d = TAILQ_NEXT(d, dv_list)) {
   1635 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
   1636 			printf("config_detach: detached device %s"
   1637 			    " has children %s\n", device_xname(dev), device_xname(d));
   1638 			panic("config_detach");
   1639 		}
   1640 	}
   1641 #endif
   1642 
   1643 	/* notify the parent that the child is gone */
   1644 	if (dev->dv_parent) {
   1645 		device_t p = dev->dv_parent;
   1646 		if (p->dv_cfattach->ca_childdetached)
   1647 			(*p->dv_cfattach->ca_childdetached)(p, dev);
   1648 	}
   1649 
   1650 	/*
   1651 	 * Mark cfdata to show that the unit can be reused, if possible.
   1652 	 */
   1653 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
   1654 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
   1655 			if (STREQ(cf->cf_name, cd->cd_name)) {
   1656 				if (cf->cf_fstate == FSTATE_FOUND &&
   1657 				    cf->cf_unit == dev->dv_unit)
   1658 					cf->cf_fstate = FSTATE_NOTFOUND;
   1659 			}
   1660 		}
   1661 	}
   1662 
   1663 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
   1664 		aprint_normal_dev(dev, "detached\n");
   1665 
   1666 out:
   1667 	config_alldevs_enter(&af);
   1668 	KASSERT(alldevs_nwrite != 0);
   1669 	--alldevs_nwrite;
   1670 	if (rv == 0 && dev->dv_del_gen == 0)
   1671 		config_devunlink(dev, &af.af_garbage);
   1672 	config_alldevs_exit(&af);
   1673 
   1674 	return rv;
   1675 }
   1676 
   1677 int
   1678 config_detach_children(device_t parent, int flags)
   1679 {
   1680 	device_t dv;
   1681 	deviter_t di;
   1682 	int error = 0;
   1683 
   1684 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
   1685 	     dv = deviter_next(&di)) {
   1686 		if (device_parent(dv) != parent)
   1687 			continue;
   1688 		if ((error = config_detach(dv, flags)) != 0)
   1689 			break;
   1690 	}
   1691 	deviter_release(&di);
   1692 	return error;
   1693 }
   1694 
   1695 device_t
   1696 shutdown_first(struct shutdown_state *s)
   1697 {
   1698 	if (!s->initialized) {
   1699 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
   1700 		s->initialized = true;
   1701 	}
   1702 	return shutdown_next(s);
   1703 }
   1704 
   1705 device_t
   1706 shutdown_next(struct shutdown_state *s)
   1707 {
   1708 	device_t dv;
   1709 
   1710 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
   1711 		;
   1712 
   1713 	if (dv == NULL)
   1714 		s->initialized = false;
   1715 
   1716 	return dv;
   1717 }
   1718 
   1719 bool
   1720 config_detach_all(int how)
   1721 {
   1722 	static struct shutdown_state s;
   1723 	device_t curdev;
   1724 	bool progress = false;
   1725 
   1726 	if ((how & RB_NOSYNC) != 0)
   1727 		return false;
   1728 
   1729 	for (curdev = shutdown_first(&s); curdev != NULL;
   1730 	     curdev = shutdown_next(&s)) {
   1731 		aprint_debug(" detaching %s, ", device_xname(curdev));
   1732 		if (config_detach(curdev, DETACH_SHUTDOWN) == 0) {
   1733 			progress = true;
   1734 			aprint_debug("success.");
   1735 		} else
   1736 			aprint_debug("failed.");
   1737 	}
   1738 	return progress;
   1739 }
   1740 
   1741 static bool
   1742 device_is_ancestor_of(device_t ancestor, device_t descendant)
   1743 {
   1744 	device_t dv;
   1745 
   1746 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
   1747 		if (device_parent(dv) == ancestor)
   1748 			return true;
   1749 	}
   1750 	return false;
   1751 }
   1752 
   1753 int
   1754 config_deactivate(device_t dev)
   1755 {
   1756 	deviter_t di;
   1757 	const struct cfattach *ca;
   1758 	device_t descendant;
   1759 	int s, rv = 0, oflags;
   1760 
   1761 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
   1762 	     descendant != NULL;
   1763 	     descendant = deviter_next(&di)) {
   1764 		if (dev != descendant &&
   1765 		    !device_is_ancestor_of(dev, descendant))
   1766 			continue;
   1767 
   1768 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
   1769 			continue;
   1770 
   1771 		ca = descendant->dv_cfattach;
   1772 		oflags = descendant->dv_flags;
   1773 
   1774 		descendant->dv_flags &= ~DVF_ACTIVE;
   1775 		if (ca->ca_activate == NULL)
   1776 			continue;
   1777 		s = splhigh();
   1778 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
   1779 		splx(s);
   1780 		if (rv != 0)
   1781 			descendant->dv_flags = oflags;
   1782 	}
   1783 	deviter_release(&di);
   1784 	return rv;
   1785 }
   1786 
   1787 /*
   1788  * Defer the configuration of the specified device until all
   1789  * of its parent's devices have been attached.
   1790  */
   1791 void
   1792 config_defer(device_t dev, void (*func)(device_t))
   1793 {
   1794 	struct deferred_config *dc;
   1795 
   1796 	if (dev->dv_parent == NULL)
   1797 		panic("config_defer: can't defer config of a root device");
   1798 
   1799 #ifdef DIAGNOSTIC
   1800 	TAILQ_FOREACH(dc, &deferred_config_queue, dc_queue) {
   1801 		if (dc->dc_dev == dev)
   1802 			panic("config_defer: deferred twice");
   1803 	}
   1804 #endif
   1805 
   1806 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
   1807 	if (dc == NULL)
   1808 		panic("config_defer: unable to allocate callback");
   1809 
   1810 	dc->dc_dev = dev;
   1811 	dc->dc_func = func;
   1812 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
   1813 	config_pending_incr();
   1814 }
   1815 
   1816 /*
   1817  * Defer some autoconfiguration for a device until after interrupts
   1818  * are enabled.
   1819  */
   1820 void
   1821 config_interrupts(device_t dev, void (*func)(device_t))
   1822 {
   1823 	struct deferred_config *dc;
   1824 
   1825 	/*
   1826 	 * If interrupts are enabled, callback now.
   1827 	 */
   1828 	if (cold == 0) {
   1829 		(*func)(dev);
   1830 		return;
   1831 	}
   1832 
   1833 #ifdef DIAGNOSTIC
   1834 	TAILQ_FOREACH(dc, &interrupt_config_queue, dc_queue) {
   1835 		if (dc->dc_dev == dev)
   1836 			panic("config_interrupts: deferred twice");
   1837 	}
   1838 #endif
   1839 
   1840 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
   1841 	if (dc == NULL)
   1842 		panic("config_interrupts: unable to allocate callback");
   1843 
   1844 	dc->dc_dev = dev;
   1845 	dc->dc_func = func;
   1846 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
   1847 	config_pending_incr();
   1848 }
   1849 
   1850 /*
   1851  * Process a deferred configuration queue.
   1852  */
   1853 static void
   1854 config_process_deferred(struct deferred_config_head *queue,
   1855     device_t parent)
   1856 {
   1857 	struct deferred_config *dc, *ndc;
   1858 
   1859 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
   1860 		ndc = TAILQ_NEXT(dc, dc_queue);
   1861 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
   1862 			TAILQ_REMOVE(queue, dc, dc_queue);
   1863 			(*dc->dc_func)(dc->dc_dev);
   1864 			kmem_free(dc, sizeof(*dc));
   1865 			config_pending_decr();
   1866 		}
   1867 	}
   1868 }
   1869 
   1870 /*
   1871  * Manipulate the config_pending semaphore.
   1872  */
   1873 void
   1874 config_pending_incr(void)
   1875 {
   1876 
   1877 	mutex_enter(&config_misc_lock);
   1878 	config_pending++;
   1879 	mutex_exit(&config_misc_lock);
   1880 }
   1881 
   1882 void
   1883 config_pending_decr(void)
   1884 {
   1885 
   1886 #ifdef DIAGNOSTIC
   1887 	if (config_pending == 0)
   1888 		panic("config_pending_decr: config_pending == 0");
   1889 #endif
   1890 	mutex_enter(&config_misc_lock);
   1891 	config_pending--;
   1892 	if (config_pending == 0)
   1893 		cv_broadcast(&config_misc_cv);
   1894 	mutex_exit(&config_misc_lock);
   1895 }
   1896 
   1897 /*
   1898  * Register a "finalization" routine.  Finalization routines are
   1899  * called iteratively once all real devices have been found during
   1900  * autoconfiguration, for as long as any one finalizer has done
   1901  * any work.
   1902  */
   1903 int
   1904 config_finalize_register(device_t dev, int (*fn)(device_t))
   1905 {
   1906 	struct finalize_hook *f;
   1907 
   1908 	/*
   1909 	 * If finalization has already been done, invoke the
   1910 	 * callback function now.
   1911 	 */
   1912 	if (config_finalize_done) {
   1913 		while ((*fn)(dev) != 0)
   1914 			/* loop */ ;
   1915 	}
   1916 
   1917 	/* Ensure this isn't already on the list. */
   1918 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
   1919 		if (f->f_func == fn && f->f_dev == dev)
   1920 			return EEXIST;
   1921 	}
   1922 
   1923 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
   1924 	f->f_func = fn;
   1925 	f->f_dev = dev;
   1926 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
   1927 
   1928 	return 0;
   1929 }
   1930 
   1931 void
   1932 config_finalize(void)
   1933 {
   1934 	struct finalize_hook *f;
   1935 	struct pdevinit *pdev;
   1936 	extern struct pdevinit pdevinit[];
   1937 	int errcnt, rv;
   1938 
   1939 	/*
   1940 	 * Now that device driver threads have been created, wait for
   1941 	 * them to finish any deferred autoconfiguration.
   1942 	 */
   1943 	mutex_enter(&config_misc_lock);
   1944 	while (config_pending != 0)
   1945 		cv_wait(&config_misc_cv, &config_misc_lock);
   1946 	mutex_exit(&config_misc_lock);
   1947 
   1948 	KERNEL_LOCK(1, NULL);
   1949 
   1950 	/* Attach pseudo-devices. */
   1951 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
   1952 		(*pdev->pdev_attach)(pdev->pdev_count);
   1953 
   1954 	/* Run the hooks until none of them does any work. */
   1955 	do {
   1956 		rv = 0;
   1957 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
   1958 			rv |= (*f->f_func)(f->f_dev);
   1959 	} while (rv != 0);
   1960 
   1961 	config_finalize_done = 1;
   1962 
   1963 	/* Now free all the hooks. */
   1964 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
   1965 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
   1966 		kmem_free(f, sizeof(*f));
   1967 	}
   1968 
   1969 	KERNEL_UNLOCK_ONE(NULL);
   1970 
   1971 	errcnt = aprint_get_error_count();
   1972 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
   1973 	    (boothowto & AB_VERBOSE) == 0) {
   1974 		mutex_enter(&config_misc_lock);
   1975 		if (config_do_twiddle) {
   1976 			config_do_twiddle = 0;
   1977 			printf_nolog(" done.\n");
   1978 		}
   1979 		mutex_exit(&config_misc_lock);
   1980 		if (errcnt != 0) {
   1981 			printf("WARNING: %d error%s while detecting hardware; "
   1982 			    "check system log.\n", errcnt,
   1983 			    errcnt == 1 ? "" : "s");
   1984 		}
   1985 	}
   1986 }
   1987 
   1988 void
   1989 config_twiddle_init()
   1990 {
   1991 
   1992 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
   1993 		config_do_twiddle = 1;
   1994 	}
   1995 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
   1996 }
   1997 
   1998 void
   1999 config_twiddle_fn(void *cookie)
   2000 {
   2001 
   2002 	mutex_enter(&config_misc_lock);
   2003 	if (config_do_twiddle) {
   2004 		twiddle();
   2005 		callout_schedule(&config_twiddle_ch, mstohz(100));
   2006 	}
   2007 	mutex_exit(&config_misc_lock);
   2008 }
   2009 
   2010 static int
   2011 config_alldevs_lock(void)
   2012 {
   2013 	mutex_enter(&alldevs_mtx);
   2014 	return 0;
   2015 }
   2016 
   2017 static void
   2018 config_alldevs_enter(struct alldevs_foray *af)
   2019 {
   2020 	TAILQ_INIT(&af->af_garbage);
   2021 	af->af_s = config_alldevs_lock();
   2022 	config_collect_garbage(&af->af_garbage);
   2023 }
   2024 
   2025 static void
   2026 config_alldevs_exit(struct alldevs_foray *af)
   2027 {
   2028 	config_alldevs_unlock(af->af_s);
   2029 	config_dump_garbage(&af->af_garbage);
   2030 }
   2031 
   2032 /*ARGSUSED*/
   2033 static void
   2034 config_alldevs_unlock(int s)
   2035 {
   2036 	mutex_exit(&alldevs_mtx);
   2037 }
   2038 
   2039 /*
   2040  * device_lookup:
   2041  *
   2042  *	Look up a device instance for a given driver.
   2043  */
   2044 device_t
   2045 device_lookup(cfdriver_t cd, int unit)
   2046 {
   2047 	device_t dv;
   2048 	int s;
   2049 
   2050 	s = config_alldevs_lock();
   2051 	KASSERT(mutex_owned(&alldevs_mtx));
   2052 	if (unit < 0 || unit >= cd->cd_ndevs)
   2053 		dv = NULL;
   2054 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
   2055 		dv = NULL;
   2056 	config_alldevs_unlock(s);
   2057 
   2058 	return dv;
   2059 }
   2060 
   2061 /*
   2062  * device_lookup_private:
   2063  *
   2064  *	Look up a softc instance for a given driver.
   2065  */
   2066 void *
   2067 device_lookup_private(cfdriver_t cd, int unit)
   2068 {
   2069 
   2070 	return device_private(device_lookup(cd, unit));
   2071 }
   2072 
   2073 /*
   2074  * device_find_by_xname:
   2075  *
   2076  *	Returns the device of the given name or NULL if it doesn't exist.
   2077  */
   2078 device_t
   2079 device_find_by_xname(const char *name)
   2080 {
   2081 	device_t dv;
   2082 	deviter_t di;
   2083 
   2084 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
   2085 		if (strcmp(device_xname(dv), name) == 0)
   2086 			break;
   2087 	}
   2088 	deviter_release(&di);
   2089 
   2090 	return dv;
   2091 }
   2092 
   2093 /*
   2094  * device_find_by_driver_unit:
   2095  *
   2096  *	Returns the device of the given driver name and unit or
   2097  *	NULL if it doesn't exist.
   2098  */
   2099 device_t
   2100 device_find_by_driver_unit(const char *name, int unit)
   2101 {
   2102 	struct cfdriver *cd;
   2103 
   2104 	if ((cd = config_cfdriver_lookup(name)) == NULL)
   2105 		return NULL;
   2106 	return device_lookup(cd, unit);
   2107 }
   2108 
   2109 /*
   2110  * Power management related functions.
   2111  */
   2112 
   2113 bool
   2114 device_pmf_is_registered(device_t dev)
   2115 {
   2116 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
   2117 }
   2118 
   2119 bool
   2120 device_pmf_driver_suspend(device_t dev, const pmf_qual_t *qual)
   2121 {
   2122 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
   2123 		return true;
   2124 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
   2125 		return false;
   2126 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
   2127 	    dev->dv_driver_suspend != NULL &&
   2128 	    !(*dev->dv_driver_suspend)(dev, qual))
   2129 		return false;
   2130 
   2131 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
   2132 	return true;
   2133 }
   2134 
   2135 bool
   2136 device_pmf_driver_resume(device_t dev, const pmf_qual_t *qual)
   2137 {
   2138 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
   2139 		return true;
   2140 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
   2141 		return false;
   2142 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
   2143 	    dev->dv_driver_resume != NULL &&
   2144 	    !(*dev->dv_driver_resume)(dev, qual))
   2145 		return false;
   2146 
   2147 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
   2148 	return true;
   2149 }
   2150 
   2151 bool
   2152 device_pmf_driver_shutdown(device_t dev, int how)
   2153 {
   2154 
   2155 	if (*dev->dv_driver_shutdown != NULL &&
   2156 	    !(*dev->dv_driver_shutdown)(dev, how))
   2157 		return false;
   2158 	return true;
   2159 }
   2160 
   2161 bool
   2162 device_pmf_driver_register(device_t dev,
   2163     bool (*suspend)(device_t, const pmf_qual_t *),
   2164     bool (*resume)(device_t, const pmf_qual_t *),
   2165     bool (*shutdown)(device_t, int))
   2166 {
   2167 	dev->dv_driver_suspend = suspend;
   2168 	dev->dv_driver_resume = resume;
   2169 	dev->dv_driver_shutdown = shutdown;
   2170 	dev->dv_flags |= DVF_POWER_HANDLERS;
   2171 	return true;
   2172 }
   2173 
   2174 static const char *
   2175 curlwp_name(void)
   2176 {
   2177 	if (curlwp->l_name != NULL)
   2178 		return curlwp->l_name;
   2179 	else
   2180 		return curlwp->l_proc->p_comm;
   2181 }
   2182 
   2183 void
   2184 device_pmf_driver_deregister(device_t dev)
   2185 {
   2186 	device_lock_t dvl = device_getlock(dev);
   2187 
   2188 	dev->dv_driver_suspend = NULL;
   2189 	dev->dv_driver_resume = NULL;
   2190 
   2191 	mutex_enter(&dvl->dvl_mtx);
   2192 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
   2193 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
   2194 		/* Wake a thread that waits for the lock.  That
   2195 		 * thread will fail to acquire the lock, and then
   2196 		 * it will wake the next thread that waits for the
   2197 		 * lock, or else it will wake us.
   2198 		 */
   2199 		cv_signal(&dvl->dvl_cv);
   2200 		pmflock_debug(dev, __func__, __LINE__);
   2201 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
   2202 		pmflock_debug(dev, __func__, __LINE__);
   2203 	}
   2204 	mutex_exit(&dvl->dvl_mtx);
   2205 }
   2206 
   2207 bool
   2208 device_pmf_driver_child_register(device_t dev)
   2209 {
   2210 	device_t parent = device_parent(dev);
   2211 
   2212 	if (parent == NULL || parent->dv_driver_child_register == NULL)
   2213 		return true;
   2214 	return (*parent->dv_driver_child_register)(dev);
   2215 }
   2216 
   2217 void
   2218 device_pmf_driver_set_child_register(device_t dev,
   2219     bool (*child_register)(device_t))
   2220 {
   2221 	dev->dv_driver_child_register = child_register;
   2222 }
   2223 
   2224 static void
   2225 pmflock_debug(device_t dev, const char *func, int line)
   2226 {
   2227 	device_lock_t dvl = device_getlock(dev);
   2228 
   2229 	aprint_debug_dev(dev, "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n",
   2230 	    func, line, curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait,
   2231 	    dev->dv_flags);
   2232 }
   2233 
   2234 static bool
   2235 device_pmf_lock1(device_t dev)
   2236 {
   2237 	device_lock_t dvl = device_getlock(dev);
   2238 
   2239 	while (device_pmf_is_registered(dev) &&
   2240 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
   2241 		dvl->dvl_nwait++;
   2242 		pmflock_debug(dev, __func__, __LINE__);
   2243 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
   2244 		pmflock_debug(dev, __func__, __LINE__);
   2245 		dvl->dvl_nwait--;
   2246 	}
   2247 	if (!device_pmf_is_registered(dev)) {
   2248 		pmflock_debug(dev, __func__, __LINE__);
   2249 		/* We could not acquire the lock, but some other thread may
   2250 		 * wait for it, also.  Wake that thread.
   2251 		 */
   2252 		cv_signal(&dvl->dvl_cv);
   2253 		return false;
   2254 	}
   2255 	dvl->dvl_nlock++;
   2256 	dvl->dvl_holder = curlwp;
   2257 	pmflock_debug(dev, __func__, __LINE__);
   2258 	return true;
   2259 }
   2260 
   2261 bool
   2262 device_pmf_lock(device_t dev)
   2263 {
   2264 	bool rc;
   2265 	device_lock_t dvl = device_getlock(dev);
   2266 
   2267 	mutex_enter(&dvl->dvl_mtx);
   2268 	rc = device_pmf_lock1(dev);
   2269 	mutex_exit(&dvl->dvl_mtx);
   2270 
   2271 	return rc;
   2272 }
   2273 
   2274 void
   2275 device_pmf_unlock(device_t dev)
   2276 {
   2277 	device_lock_t dvl = device_getlock(dev);
   2278 
   2279 	KASSERT(dvl->dvl_nlock > 0);
   2280 	mutex_enter(&dvl->dvl_mtx);
   2281 	if (--dvl->dvl_nlock == 0)
   2282 		dvl->dvl_holder = NULL;
   2283 	cv_signal(&dvl->dvl_cv);
   2284 	pmflock_debug(dev, __func__, __LINE__);
   2285 	mutex_exit(&dvl->dvl_mtx);
   2286 }
   2287 
   2288 device_lock_t
   2289 device_getlock(device_t dev)
   2290 {
   2291 	return &dev->dv_lock;
   2292 }
   2293 
   2294 void *
   2295 device_pmf_bus_private(device_t dev)
   2296 {
   2297 	return dev->dv_bus_private;
   2298 }
   2299 
   2300 bool
   2301 device_pmf_bus_suspend(device_t dev, const pmf_qual_t *qual)
   2302 {
   2303 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
   2304 		return true;
   2305 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
   2306 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
   2307 		return false;
   2308 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
   2309 	    dev->dv_bus_suspend != NULL &&
   2310 	    !(*dev->dv_bus_suspend)(dev, qual))
   2311 		return false;
   2312 
   2313 	dev->dv_flags |= DVF_BUS_SUSPENDED;
   2314 	return true;
   2315 }
   2316 
   2317 bool
   2318 device_pmf_bus_resume(device_t dev, const pmf_qual_t *qual)
   2319 {
   2320 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
   2321 		return true;
   2322 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
   2323 	    dev->dv_bus_resume != NULL &&
   2324 	    !(*dev->dv_bus_resume)(dev, qual))
   2325 		return false;
   2326 
   2327 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
   2328 	return true;
   2329 }
   2330 
   2331 bool
   2332 device_pmf_bus_shutdown(device_t dev, int how)
   2333 {
   2334 
   2335 	if (*dev->dv_bus_shutdown != NULL &&
   2336 	    !(*dev->dv_bus_shutdown)(dev, how))
   2337 		return false;
   2338 	return true;
   2339 }
   2340 
   2341 void
   2342 device_pmf_bus_register(device_t dev, void *priv,
   2343     bool (*suspend)(device_t, const pmf_qual_t *),
   2344     bool (*resume)(device_t, const pmf_qual_t *),
   2345     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
   2346 {
   2347 	dev->dv_bus_private = priv;
   2348 	dev->dv_bus_resume = resume;
   2349 	dev->dv_bus_suspend = suspend;
   2350 	dev->dv_bus_shutdown = shutdown;
   2351 	dev->dv_bus_deregister = deregister;
   2352 }
   2353 
   2354 void
   2355 device_pmf_bus_deregister(device_t dev)
   2356 {
   2357 	if (dev->dv_bus_deregister == NULL)
   2358 		return;
   2359 	(*dev->dv_bus_deregister)(dev);
   2360 	dev->dv_bus_private = NULL;
   2361 	dev->dv_bus_suspend = NULL;
   2362 	dev->dv_bus_resume = NULL;
   2363 	dev->dv_bus_deregister = NULL;
   2364 }
   2365 
   2366 void *
   2367 device_pmf_class_private(device_t dev)
   2368 {
   2369 	return dev->dv_class_private;
   2370 }
   2371 
   2372 bool
   2373 device_pmf_class_suspend(device_t dev, const pmf_qual_t *qual)
   2374 {
   2375 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
   2376 		return true;
   2377 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
   2378 	    dev->dv_class_suspend != NULL &&
   2379 	    !(*dev->dv_class_suspend)(dev, qual))
   2380 		return false;
   2381 
   2382 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
   2383 	return true;
   2384 }
   2385 
   2386 bool
   2387 device_pmf_class_resume(device_t dev, const pmf_qual_t *qual)
   2388 {
   2389 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
   2390 		return true;
   2391 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
   2392 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
   2393 		return false;
   2394 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
   2395 	    dev->dv_class_resume != NULL &&
   2396 	    !(*dev->dv_class_resume)(dev, qual))
   2397 		return false;
   2398 
   2399 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
   2400 	return true;
   2401 }
   2402 
   2403 void
   2404 device_pmf_class_register(device_t dev, void *priv,
   2405     bool (*suspend)(device_t, const pmf_qual_t *),
   2406     bool (*resume)(device_t, const pmf_qual_t *),
   2407     void (*deregister)(device_t))
   2408 {
   2409 	dev->dv_class_private = priv;
   2410 	dev->dv_class_suspend = suspend;
   2411 	dev->dv_class_resume = resume;
   2412 	dev->dv_class_deregister = deregister;
   2413 }
   2414 
   2415 void
   2416 device_pmf_class_deregister(device_t dev)
   2417 {
   2418 	if (dev->dv_class_deregister == NULL)
   2419 		return;
   2420 	(*dev->dv_class_deregister)(dev);
   2421 	dev->dv_class_private = NULL;
   2422 	dev->dv_class_suspend = NULL;
   2423 	dev->dv_class_resume = NULL;
   2424 	dev->dv_class_deregister = NULL;
   2425 }
   2426 
   2427 bool
   2428 device_active(device_t dev, devactive_t type)
   2429 {
   2430 	size_t i;
   2431 
   2432 	if (dev->dv_activity_count == 0)
   2433 		return false;
   2434 
   2435 	for (i = 0; i < dev->dv_activity_count; ++i) {
   2436 		if (dev->dv_activity_handlers[i] == NULL)
   2437 			break;
   2438 		(*dev->dv_activity_handlers[i])(dev, type);
   2439 	}
   2440 
   2441 	return true;
   2442 }
   2443 
   2444 bool
   2445 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
   2446 {
   2447 	void (**new_handlers)(device_t, devactive_t);
   2448 	void (**old_handlers)(device_t, devactive_t);
   2449 	size_t i, old_size, new_size;
   2450 	int s;
   2451 
   2452 	old_handlers = dev->dv_activity_handlers;
   2453 	old_size = dev->dv_activity_count;
   2454 
   2455 	for (i = 0; i < old_size; ++i) {
   2456 		KASSERT(old_handlers[i] != handler);
   2457 		if (old_handlers[i] == NULL) {
   2458 			old_handlers[i] = handler;
   2459 			return true;
   2460 		}
   2461 	}
   2462 
   2463 	new_size = old_size + 4;
   2464 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
   2465 
   2466 	memcpy(new_handlers, old_handlers, sizeof(void *[old_size]));
   2467 	new_handlers[old_size] = handler;
   2468 	memset(new_handlers + old_size + 1, 0,
   2469 	    sizeof(int [new_size - (old_size+1)]));
   2470 
   2471 	s = splhigh();
   2472 	dev->dv_activity_count = new_size;
   2473 	dev->dv_activity_handlers = new_handlers;
   2474 	splx(s);
   2475 
   2476 	if (old_handlers != NULL)
   2477 		kmem_free(old_handlers, sizeof(void * [old_size]));
   2478 
   2479 	return true;
   2480 }
   2481 
   2482 void
   2483 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
   2484 {
   2485 	void (**old_handlers)(device_t, devactive_t);
   2486 	size_t i, old_size;
   2487 	int s;
   2488 
   2489 	old_handlers = dev->dv_activity_handlers;
   2490 	old_size = dev->dv_activity_count;
   2491 
   2492 	for (i = 0; i < old_size; ++i) {
   2493 		if (old_handlers[i] == handler)
   2494 			break;
   2495 		if (old_handlers[i] == NULL)
   2496 			return; /* XXX panic? */
   2497 	}
   2498 
   2499 	if (i == old_size)
   2500 		return; /* XXX panic? */
   2501 
   2502 	for (; i < old_size - 1; ++i) {
   2503 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
   2504 			continue;
   2505 
   2506 		if (i == 0) {
   2507 			s = splhigh();
   2508 			dev->dv_activity_count = 0;
   2509 			dev->dv_activity_handlers = NULL;
   2510 			splx(s);
   2511 			kmem_free(old_handlers, sizeof(void *[old_size]));
   2512 		}
   2513 		return;
   2514 	}
   2515 	old_handlers[i] = NULL;
   2516 }
   2517 
   2518 /* Return true iff the device_t `dev' exists at generation `gen'. */
   2519 static bool
   2520 device_exists_at(device_t dv, devgen_t gen)
   2521 {
   2522 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
   2523 	    dv->dv_add_gen <= gen;
   2524 }
   2525 
   2526 static bool
   2527 deviter_visits(const deviter_t *di, device_t dv)
   2528 {
   2529 	return device_exists_at(dv, di->di_gen);
   2530 }
   2531 
   2532 /*
   2533  * Device Iteration
   2534  *
   2535  * deviter_t: a device iterator.  Holds state for a "walk" visiting
   2536  *     each device_t's in the device tree.
   2537  *
   2538  * deviter_init(di, flags): initialize the device iterator `di'
   2539  *     to "walk" the device tree.  deviter_next(di) will return
   2540  *     the first device_t in the device tree, or NULL if there are
   2541  *     no devices.
   2542  *
   2543  *     `flags' is one or more of DEVITER_F_RW, indicating that the
   2544  *     caller intends to modify the device tree by calling
   2545  *     config_detach(9) on devices in the order that the iterator
   2546  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
   2547  *     nearest the "root" of the device tree to be returned, first;
   2548  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
   2549  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
   2550  *     indicating both that deviter_init() should not respect any
   2551  *     locks on the device tree, and that deviter_next(di) may run
   2552  *     in more than one LWP before the walk has finished.
   2553  *
   2554  *     Only one DEVITER_F_RW iterator may be in the device tree at
   2555  *     once.
   2556  *
   2557  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
   2558  *
   2559  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
   2560  *     DEVITER_F_LEAVES_FIRST are used in combination.
   2561  *
   2562  * deviter_first(di, flags): initialize the device iterator `di'
   2563  *     and return the first device_t in the device tree, or NULL
   2564  *     if there are no devices.  The statement
   2565  *
   2566  *         dv = deviter_first(di);
   2567  *
   2568  *     is shorthand for
   2569  *
   2570  *         deviter_init(di);
   2571  *         dv = deviter_next(di);
   2572  *
   2573  * deviter_next(di): return the next device_t in the device tree,
   2574  *     or NULL if there are no more devices.  deviter_next(di)
   2575  *     is undefined if `di' was not initialized with deviter_init() or
   2576  *     deviter_first().
   2577  *
   2578  * deviter_release(di): stops iteration (subsequent calls to
   2579  *     deviter_next() will return NULL), releases any locks and
   2580  *     resources held by the device iterator.
   2581  *
   2582  * Device iteration does not return device_t's in any particular
   2583  * order.  An iterator will never return the same device_t twice.
   2584  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
   2585  * is called repeatedly on the same `di', it will eventually return
   2586  * NULL.  It is ok to attach/detach devices during device iteration.
   2587  */
   2588 void
   2589 deviter_init(deviter_t *di, deviter_flags_t flags)
   2590 {
   2591 	device_t dv;
   2592 	int s;
   2593 
   2594 	memset(di, 0, sizeof(*di));
   2595 
   2596 	s = config_alldevs_lock();
   2597 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
   2598 		flags |= DEVITER_F_RW;
   2599 
   2600 	if ((flags & DEVITER_F_RW) != 0)
   2601 		alldevs_nwrite++;
   2602 	else
   2603 		alldevs_nread++;
   2604 	di->di_gen = alldevs_gen++;
   2605 	config_alldevs_unlock(s);
   2606 
   2607 	di->di_flags = flags;
   2608 
   2609 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
   2610 	case DEVITER_F_LEAVES_FIRST:
   2611 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   2612 			if (!deviter_visits(di, dv))
   2613 				continue;
   2614 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
   2615 		}
   2616 		break;
   2617 	case DEVITER_F_ROOT_FIRST:
   2618 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   2619 			if (!deviter_visits(di, dv))
   2620 				continue;
   2621 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
   2622 		}
   2623 		break;
   2624 	default:
   2625 		break;
   2626 	}
   2627 
   2628 	deviter_reinit(di);
   2629 }
   2630 
   2631 static void
   2632 deviter_reinit(deviter_t *di)
   2633 {
   2634 	if ((di->di_flags & DEVITER_F_RW) != 0)
   2635 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
   2636 	else
   2637 		di->di_prev = TAILQ_FIRST(&alldevs);
   2638 }
   2639 
   2640 device_t
   2641 deviter_first(deviter_t *di, deviter_flags_t flags)
   2642 {
   2643 	deviter_init(di, flags);
   2644 	return deviter_next(di);
   2645 }
   2646 
   2647 static device_t
   2648 deviter_next2(deviter_t *di)
   2649 {
   2650 	device_t dv;
   2651 
   2652 	dv = di->di_prev;
   2653 
   2654 	if (dv == NULL)
   2655 		return NULL;
   2656 
   2657 	if ((di->di_flags & DEVITER_F_RW) != 0)
   2658 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
   2659 	else
   2660 		di->di_prev = TAILQ_NEXT(dv, dv_list);
   2661 
   2662 	return dv;
   2663 }
   2664 
   2665 static device_t
   2666 deviter_next1(deviter_t *di)
   2667 {
   2668 	device_t dv;
   2669 
   2670 	do {
   2671 		dv = deviter_next2(di);
   2672 	} while (dv != NULL && !deviter_visits(di, dv));
   2673 
   2674 	return dv;
   2675 }
   2676 
   2677 device_t
   2678 deviter_next(deviter_t *di)
   2679 {
   2680 	device_t dv = NULL;
   2681 
   2682 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
   2683 	case 0:
   2684 		return deviter_next1(di);
   2685 	case DEVITER_F_LEAVES_FIRST:
   2686 		while (di->di_curdepth >= 0) {
   2687 			if ((dv = deviter_next1(di)) == NULL) {
   2688 				di->di_curdepth--;
   2689 				deviter_reinit(di);
   2690 			} else if (dv->dv_depth == di->di_curdepth)
   2691 				break;
   2692 		}
   2693 		return dv;
   2694 	case DEVITER_F_ROOT_FIRST:
   2695 		while (di->di_curdepth <= di->di_maxdepth) {
   2696 			if ((dv = deviter_next1(di)) == NULL) {
   2697 				di->di_curdepth++;
   2698 				deviter_reinit(di);
   2699 			} else if (dv->dv_depth == di->di_curdepth)
   2700 				break;
   2701 		}
   2702 		return dv;
   2703 	default:
   2704 		return NULL;
   2705 	}
   2706 }
   2707 
   2708 void
   2709 deviter_release(deviter_t *di)
   2710 {
   2711 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
   2712 	int s;
   2713 
   2714 	s = config_alldevs_lock();
   2715 	if (rw)
   2716 		--alldevs_nwrite;
   2717 	else
   2718 		--alldevs_nread;
   2719 	/* XXX wake a garbage-collection thread */
   2720 	config_alldevs_unlock(s);
   2721 }
   2722 
   2723 const char *
   2724 cfdata_ifattr(const struct cfdata *cf)
   2725 {
   2726 	return cf->cf_pspec->cfp_iattr;
   2727 }
   2728 
   2729 bool
   2730 ifattr_match(const char *snull, const char *t)
   2731 {
   2732 	return (snull == NULL) || strcmp(snull, t) == 0;
   2733 }
   2734 
   2735 void
   2736 null_childdetached(device_t self, device_t child)
   2737 {
   2738 	/* do nothing */
   2739 }
   2740 
   2741 static void
   2742 sysctl_detach_setup(struct sysctllog **clog)
   2743 {
   2744 	const struct sysctlnode *node = NULL;
   2745 
   2746 	sysctl_createv(clog, 0, NULL, &node,
   2747 		CTLFLAG_PERMANENT,
   2748 		CTLTYPE_NODE, "kern", NULL,
   2749 		NULL, 0, NULL, 0,
   2750 		CTL_KERN, CTL_EOL);
   2751 
   2752 	if (node == NULL)
   2753 		return;
   2754 
   2755 	sysctl_createv(clog, 0, &node, NULL,
   2756 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
   2757 		CTLTYPE_BOOL, "detachall",
   2758 		SYSCTL_DESCR("Detach all devices at shutdown"),
   2759 		NULL, 0, &detachall, 0,
   2760 		CTL_CREATE, CTL_EOL);
   2761 }
   2762