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subr_autoconf.c revision 1.263
      1 /* $NetBSD: subr_autoconf.c,v 1.263 2018/09/18 01:25:09 mrg 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 1.263 2018/09/18 01:25:09 mrg Exp $");
     81 
     82 #ifdef _KERNEL_OPT
     83 #include "opt_ddb.h"
     84 #include "drvctl.h"
     85 #endif
     86 
     87 #include <sys/param.h>
     88 #include <sys/device.h>
     89 #include <sys/disklabel.h>
     90 #include <sys/conf.h>
     91 #include <sys/kauth.h>
     92 #include <sys/kmem.h>
     93 #include <sys/systm.h>
     94 #include <sys/kernel.h>
     95 #include <sys/errno.h>
     96 #include <sys/proc.h>
     97 #include <sys/reboot.h>
     98 #include <sys/kthread.h>
     99 #include <sys/buf.h>
    100 #include <sys/dirent.h>
    101 #include <sys/mount.h>
    102 #include <sys/namei.h>
    103 #include <sys/unistd.h>
    104 #include <sys/fcntl.h>
    105 #include <sys/lockf.h>
    106 #include <sys/callout.h>
    107 #include <sys/devmon.h>
    108 #include <sys/cpu.h>
    109 #include <sys/sysctl.h>
    110 
    111 #include <sys/disk.h>
    112 
    113 #include <sys/rndsource.h>
    114 
    115 #include <machine/limits.h>
    116 
    117 /*
    118  * Autoconfiguration subroutines.
    119  */
    120 
    121 /*
    122  * Device autoconfiguration timings are mixed into the entropy pool.
    123  */
    124 extern krndsource_t rnd_autoconf_source;
    125 
    126 /*
    127  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
    128  * devices and drivers are found via these tables.
    129  */
    130 extern struct cfdata cfdata[];
    131 extern const short cfroots[];
    132 
    133 /*
    134  * List of all cfdriver structures.  We use this to detect duplicates
    135  * when other cfdrivers are loaded.
    136  */
    137 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
    138 extern struct cfdriver * const cfdriver_list_initial[];
    139 
    140 /*
    141  * Initial list of cfattach's.
    142  */
    143 extern const struct cfattachinit cfattachinit[];
    144 
    145 /*
    146  * List of cfdata tables.  We always have one such list -- the one
    147  * built statically when the kernel was configured.
    148  */
    149 struct cftablelist allcftables = TAILQ_HEAD_INITIALIZER(allcftables);
    150 static struct cftable initcftable;
    151 
    152 #define	ROOT ((device_t)NULL)
    153 
    154 struct matchinfo {
    155 	cfsubmatch_t fn;
    156 	device_t parent;
    157 	const int *locs;
    158 	void	*aux;
    159 	struct	cfdata *match;
    160 	int	pri;
    161 };
    162 
    163 struct alldevs_foray {
    164 	int			af_s;
    165 	struct devicelist	af_garbage;
    166 };
    167 
    168 static char *number(char *, int);
    169 static void mapply(struct matchinfo *, cfdata_t);
    170 static device_t config_devalloc(const device_t, const cfdata_t, const int *);
    171 static void config_devdelete(device_t);
    172 static void config_devunlink(device_t, struct devicelist *);
    173 static void config_makeroom(int, struct cfdriver *);
    174 static void config_devlink(device_t);
    175 static void config_alldevs_enter(struct alldevs_foray *);
    176 static void config_alldevs_exit(struct alldevs_foray *);
    177 static void config_add_attrib_dict(device_t);
    178 
    179 static void config_collect_garbage(struct devicelist *);
    180 static void config_dump_garbage(struct devicelist *);
    181 
    182 static void pmflock_debug(device_t, const char *, int);
    183 
    184 static device_t deviter_next1(deviter_t *);
    185 static void deviter_reinit(deviter_t *);
    186 
    187 struct deferred_config {
    188 	TAILQ_ENTRY(deferred_config) dc_queue;
    189 	device_t dc_dev;
    190 	void (*dc_func)(device_t);
    191 };
    192 
    193 TAILQ_HEAD(deferred_config_head, deferred_config);
    194 
    195 static struct deferred_config_head deferred_config_queue =
    196 	TAILQ_HEAD_INITIALIZER(deferred_config_queue);
    197 static struct deferred_config_head interrupt_config_queue =
    198 	TAILQ_HEAD_INITIALIZER(interrupt_config_queue);
    199 static int interrupt_config_threads = 8;
    200 static struct deferred_config_head mountroot_config_queue =
    201 	TAILQ_HEAD_INITIALIZER(mountroot_config_queue);
    202 static int mountroot_config_threads = 2;
    203 static lwp_t **mountroot_config_lwpids;
    204 static size_t mountroot_config_lwpids_size;
    205 bool root_is_mounted = false;
    206 
    207 static void config_process_deferred(struct deferred_config_head *, device_t);
    208 
    209 /* Hooks to finalize configuration once all real devices have been found. */
    210 struct finalize_hook {
    211 	TAILQ_ENTRY(finalize_hook) f_list;
    212 	int (*f_func)(device_t);
    213 	device_t f_dev;
    214 };
    215 static TAILQ_HEAD(, finalize_hook) config_finalize_list =
    216 	TAILQ_HEAD_INITIALIZER(config_finalize_list);
    217 static int config_finalize_done;
    218 
    219 /* list of all devices */
    220 static struct devicelist alldevs = TAILQ_HEAD_INITIALIZER(alldevs);
    221 static kmutex_t alldevs_lock __cacheline_aligned;
    222 static devgen_t alldevs_gen = 1;
    223 static int alldevs_nread = 0;
    224 static int alldevs_nwrite = 0;
    225 static bool alldevs_garbage = false;
    226 
    227 static int config_pending;		/* semaphore for mountroot */
    228 static kmutex_t config_misc_lock;
    229 static kcondvar_t config_misc_cv;
    230 
    231 static bool detachall = false;
    232 
    233 #define	STREQ(s1, s2)			\
    234 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
    235 
    236 static bool config_initialized = false;	/* config_init() has been called. */
    237 
    238 static int config_do_twiddle;
    239 static callout_t config_twiddle_ch;
    240 
    241 static void sysctl_detach_setup(struct sysctllog **);
    242 
    243 int no_devmon_insert(const char *, prop_dictionary_t);
    244 int (*devmon_insert_vec)(const char *, prop_dictionary_t) = no_devmon_insert;
    245 
    246 typedef int (*cfdriver_fn)(struct cfdriver *);
    247 static int
    248 frob_cfdrivervec(struct cfdriver * const *cfdriverv,
    249 	cfdriver_fn drv_do, cfdriver_fn drv_undo,
    250 	const char *style, bool dopanic)
    251 {
    252 	void (*pr)(const char *, ...) __printflike(1, 2) =
    253 	    dopanic ? panic : printf;
    254 	int i, error = 0, e2 __diagused;
    255 
    256 	for (i = 0; cfdriverv[i] != NULL; i++) {
    257 		if ((error = drv_do(cfdriverv[i])) != 0) {
    258 			pr("configure: `%s' driver %s failed: %d",
    259 			    cfdriverv[i]->cd_name, style, error);
    260 			goto bad;
    261 		}
    262 	}
    263 
    264 	KASSERT(error == 0);
    265 	return 0;
    266 
    267  bad:
    268 	printf("\n");
    269 	for (i--; i >= 0; i--) {
    270 		e2 = drv_undo(cfdriverv[i]);
    271 		KASSERT(e2 == 0);
    272 	}
    273 
    274 	return error;
    275 }
    276 
    277 typedef int (*cfattach_fn)(const char *, struct cfattach *);
    278 static int
    279 frob_cfattachvec(const struct cfattachinit *cfattachv,
    280 	cfattach_fn att_do, cfattach_fn att_undo,
    281 	const char *style, bool dopanic)
    282 {
    283 	const struct cfattachinit *cfai = NULL;
    284 	void (*pr)(const char *, ...) __printflike(1, 2) =
    285 	    dopanic ? panic : printf;
    286 	int j = 0, error = 0, e2 __diagused;
    287 
    288 	for (cfai = &cfattachv[0]; cfai->cfai_name != NULL; cfai++) {
    289 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
    290 			if ((error = att_do(cfai->cfai_name,
    291 			    cfai->cfai_list[j])) != 0) {
    292 				pr("configure: attachment `%s' "
    293 				    "of `%s' driver %s failed: %d",
    294 				    cfai->cfai_list[j]->ca_name,
    295 				    cfai->cfai_name, style, error);
    296 				goto bad;
    297 			}
    298 		}
    299 	}
    300 
    301 	KASSERT(error == 0);
    302 	return 0;
    303 
    304  bad:
    305 	/*
    306 	 * Rollback in reverse order.  dunno if super-important, but
    307 	 * do that anyway.  Although the code looks a little like
    308 	 * someone did a little integration (in the math sense).
    309 	 */
    310 	printf("\n");
    311 	if (cfai) {
    312 		bool last;
    313 
    314 		for (last = false; last == false; ) {
    315 			if (cfai == &cfattachv[0])
    316 				last = true;
    317 			for (j--; j >= 0; j--) {
    318 				e2 = att_undo(cfai->cfai_name,
    319 				    cfai->cfai_list[j]);
    320 				KASSERT(e2 == 0);
    321 			}
    322 			if (!last) {
    323 				cfai--;
    324 				for (j = 0; cfai->cfai_list[j] != NULL; j++)
    325 					;
    326 			}
    327 		}
    328 	}
    329 
    330 	return error;
    331 }
    332 
    333 /*
    334  * Initialize the autoconfiguration data structures.  Normally this
    335  * is done by configure(), but some platforms need to do this very
    336  * early (to e.g. initialize the console).
    337  */
    338 void
    339 config_init(void)
    340 {
    341 
    342 	KASSERT(config_initialized == false);
    343 
    344 	mutex_init(&alldevs_lock, MUTEX_DEFAULT, IPL_VM);
    345 
    346 	mutex_init(&config_misc_lock, MUTEX_DEFAULT, IPL_NONE);
    347 	cv_init(&config_misc_cv, "cfgmisc");
    348 
    349 	callout_init(&config_twiddle_ch, CALLOUT_MPSAFE);
    350 
    351 	frob_cfdrivervec(cfdriver_list_initial,
    352 	    config_cfdriver_attach, NULL, "bootstrap", true);
    353 	frob_cfattachvec(cfattachinit,
    354 	    config_cfattach_attach, NULL, "bootstrap", true);
    355 
    356 	initcftable.ct_cfdata = cfdata;
    357 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
    358 
    359 	config_initialized = true;
    360 }
    361 
    362 /*
    363  * Init or fini drivers and attachments.  Either all or none
    364  * are processed (via rollback).  It would be nice if this were
    365  * atomic to outside consumers, but with the current state of
    366  * locking ...
    367  */
    368 int
    369 config_init_component(struct cfdriver * const *cfdriverv,
    370 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
    371 {
    372 	int error;
    373 
    374 	if ((error = frob_cfdrivervec(cfdriverv,
    375 	    config_cfdriver_attach, config_cfdriver_detach, "init", false))!= 0)
    376 		return error;
    377 	if ((error = frob_cfattachvec(cfattachv,
    378 	    config_cfattach_attach, config_cfattach_detach,
    379 	    "init", false)) != 0) {
    380 		frob_cfdrivervec(cfdriverv,
    381 	            config_cfdriver_detach, NULL, "init rollback", true);
    382 		return error;
    383 	}
    384 	if ((error = config_cfdata_attach(cfdatav, 1)) != 0) {
    385 		frob_cfattachvec(cfattachv,
    386 		    config_cfattach_detach, NULL, "init rollback", true);
    387 		frob_cfdrivervec(cfdriverv,
    388 	            config_cfdriver_detach, NULL, "init rollback", true);
    389 		return error;
    390 	}
    391 
    392 	return 0;
    393 }
    394 
    395 int
    396 config_fini_component(struct cfdriver * const *cfdriverv,
    397 	const struct cfattachinit *cfattachv, struct cfdata *cfdatav)
    398 {
    399 	int error;
    400 
    401 	if ((error = config_cfdata_detach(cfdatav)) != 0)
    402 		return error;
    403 	if ((error = frob_cfattachvec(cfattachv,
    404 	    config_cfattach_detach, config_cfattach_attach,
    405 	    "fini", false)) != 0) {
    406 		if (config_cfdata_attach(cfdatav, 0) != 0)
    407 			panic("config_cfdata fini rollback failed");
    408 		return error;
    409 	}
    410 	if ((error = frob_cfdrivervec(cfdriverv,
    411 	    config_cfdriver_detach, config_cfdriver_attach,
    412 	    "fini", false)) != 0) {
    413 		frob_cfattachvec(cfattachv,
    414 	            config_cfattach_attach, NULL, "fini rollback", true);
    415 		if (config_cfdata_attach(cfdatav, 0) != 0)
    416 			panic("config_cfdata fini rollback failed");
    417 		return error;
    418 	}
    419 
    420 	return 0;
    421 }
    422 
    423 void
    424 config_init_mi(void)
    425 {
    426 
    427 	if (!config_initialized)
    428 		config_init();
    429 
    430 	sysctl_detach_setup(NULL);
    431 }
    432 
    433 void
    434 config_deferred(device_t dev)
    435 {
    436 	config_process_deferred(&deferred_config_queue, dev);
    437 	config_process_deferred(&interrupt_config_queue, dev);
    438 	config_process_deferred(&mountroot_config_queue, dev);
    439 }
    440 
    441 static void
    442 config_interrupts_thread(void *cookie)
    443 {
    444 	struct deferred_config *dc;
    445 
    446 	while ((dc = TAILQ_FIRST(&interrupt_config_queue)) != NULL) {
    447 		TAILQ_REMOVE(&interrupt_config_queue, dc, dc_queue);
    448 		(*dc->dc_func)(dc->dc_dev);
    449 		config_pending_decr(dc->dc_dev);
    450 		kmem_free(dc, sizeof(*dc));
    451 	}
    452 	kthread_exit(0);
    453 }
    454 
    455 void
    456 config_create_interruptthreads(void)
    457 {
    458 	int i;
    459 
    460 	for (i = 0; i < interrupt_config_threads; i++) {
    461 		(void)kthread_create(PRI_NONE, 0, NULL,
    462 		    config_interrupts_thread, NULL, NULL, "configintr");
    463 	}
    464 }
    465 
    466 static void
    467 config_mountroot_thread(void *cookie)
    468 {
    469 	struct deferred_config *dc;
    470 
    471 	while ((dc = TAILQ_FIRST(&mountroot_config_queue)) != NULL) {
    472 		TAILQ_REMOVE(&mountroot_config_queue, dc, dc_queue);
    473 		(*dc->dc_func)(dc->dc_dev);
    474 		kmem_free(dc, sizeof(*dc));
    475 	}
    476 	kthread_exit(0);
    477 }
    478 
    479 void
    480 config_create_mountrootthreads(void)
    481 {
    482 	int i;
    483 
    484 	if (!root_is_mounted)
    485 		root_is_mounted = true;
    486 
    487 	mountroot_config_lwpids_size = sizeof(mountroot_config_lwpids) *
    488 				       mountroot_config_threads;
    489 	mountroot_config_lwpids = kmem_alloc(mountroot_config_lwpids_size,
    490 					     KM_NOSLEEP);
    491 	KASSERT(mountroot_config_lwpids);
    492 	for (i = 0; i < mountroot_config_threads; i++) {
    493 		mountroot_config_lwpids[i] = 0;
    494 		(void)kthread_create(PRI_NONE, KTHREAD_MUSTJOIN, NULL,
    495 				     config_mountroot_thread, NULL,
    496 				     &mountroot_config_lwpids[i],
    497 				     "configroot");
    498 	}
    499 }
    500 
    501 void
    502 config_finalize_mountroot(void)
    503 {
    504 	int i, error;
    505 
    506 	for (i = 0; i < mountroot_config_threads; i++) {
    507 		if (mountroot_config_lwpids[i] == 0)
    508 			continue;
    509 
    510 		error = kthread_join(mountroot_config_lwpids[i]);
    511 		if (error)
    512 			printf("%s: thread %x joined with error %d\n",
    513 			       __func__, i, error);
    514 	}
    515 	kmem_free(mountroot_config_lwpids, mountroot_config_lwpids_size);
    516 }
    517 
    518 /*
    519  * Announce device attach/detach to userland listeners.
    520  */
    521 
    522 int
    523 no_devmon_insert(const char *name, prop_dictionary_t p)
    524 {
    525 
    526 	return ENODEV;
    527 }
    528 
    529 static void
    530 devmon_report_device(device_t dev, bool isattach)
    531 {
    532 	prop_dictionary_t ev;
    533 	const char *parent;
    534 	const char *what;
    535 	device_t pdev = device_parent(dev);
    536 
    537 	/* If currently no drvctl device, just return */
    538 	if (devmon_insert_vec == no_devmon_insert)
    539 		return;
    540 
    541 	ev = prop_dictionary_create();
    542 	if (ev == NULL)
    543 		return;
    544 
    545 	what = (isattach ? "device-attach" : "device-detach");
    546 	parent = (pdev == NULL ? "root" : device_xname(pdev));
    547 	if (!prop_dictionary_set_cstring(ev, "device", device_xname(dev)) ||
    548 	    !prop_dictionary_set_cstring(ev, "parent", parent)) {
    549 		prop_object_release(ev);
    550 		return;
    551 	}
    552 
    553 	if ((*devmon_insert_vec)(what, ev) != 0)
    554 		prop_object_release(ev);
    555 }
    556 
    557 /*
    558  * Add a cfdriver to the system.
    559  */
    560 int
    561 config_cfdriver_attach(struct cfdriver *cd)
    562 {
    563 	struct cfdriver *lcd;
    564 
    565 	/* Make sure this driver isn't already in the system. */
    566 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
    567 		if (STREQ(lcd->cd_name, cd->cd_name))
    568 			return EEXIST;
    569 	}
    570 
    571 	LIST_INIT(&cd->cd_attach);
    572 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
    573 
    574 	return 0;
    575 }
    576 
    577 /*
    578  * Remove a cfdriver from the system.
    579  */
    580 int
    581 config_cfdriver_detach(struct cfdriver *cd)
    582 {
    583 	struct alldevs_foray af;
    584 	int i, rc = 0;
    585 
    586 	config_alldevs_enter(&af);
    587 	/* Make sure there are no active instances. */
    588 	for (i = 0; i < cd->cd_ndevs; i++) {
    589 		if (cd->cd_devs[i] != NULL) {
    590 			rc = EBUSY;
    591 			break;
    592 		}
    593 	}
    594 	config_alldevs_exit(&af);
    595 
    596 	if (rc != 0)
    597 		return rc;
    598 
    599 	/* ...and no attachments loaded. */
    600 	if (LIST_EMPTY(&cd->cd_attach) == 0)
    601 		return EBUSY;
    602 
    603 	LIST_REMOVE(cd, cd_list);
    604 
    605 	KASSERT(cd->cd_devs == NULL);
    606 
    607 	return 0;
    608 }
    609 
    610 /*
    611  * Look up a cfdriver by name.
    612  */
    613 struct cfdriver *
    614 config_cfdriver_lookup(const char *name)
    615 {
    616 	struct cfdriver *cd;
    617 
    618 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
    619 		if (STREQ(cd->cd_name, name))
    620 			return cd;
    621 	}
    622 
    623 	return NULL;
    624 }
    625 
    626 /*
    627  * Add a cfattach to the specified driver.
    628  */
    629 int
    630 config_cfattach_attach(const char *driver, struct cfattach *ca)
    631 {
    632 	struct cfattach *lca;
    633 	struct cfdriver *cd;
    634 
    635 	cd = config_cfdriver_lookup(driver);
    636 	if (cd == NULL)
    637 		return ESRCH;
    638 
    639 	/* Make sure this attachment isn't already on this driver. */
    640 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
    641 		if (STREQ(lca->ca_name, ca->ca_name))
    642 			return EEXIST;
    643 	}
    644 
    645 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
    646 
    647 	return 0;
    648 }
    649 
    650 /*
    651  * Remove a cfattach from the specified driver.
    652  */
    653 int
    654 config_cfattach_detach(const char *driver, struct cfattach *ca)
    655 {
    656 	struct alldevs_foray af;
    657 	struct cfdriver *cd;
    658 	device_t dev;
    659 	int i, rc = 0;
    660 
    661 	cd = config_cfdriver_lookup(driver);
    662 	if (cd == NULL)
    663 		return ESRCH;
    664 
    665 	config_alldevs_enter(&af);
    666 	/* Make sure there are no active instances. */
    667 	for (i = 0; i < cd->cd_ndevs; i++) {
    668 		if ((dev = cd->cd_devs[i]) == NULL)
    669 			continue;
    670 		if (dev->dv_cfattach == ca) {
    671 			rc = EBUSY;
    672 			break;
    673 		}
    674 	}
    675 	config_alldevs_exit(&af);
    676 
    677 	if (rc != 0)
    678 		return rc;
    679 
    680 	LIST_REMOVE(ca, ca_list);
    681 
    682 	return 0;
    683 }
    684 
    685 /*
    686  * Look up a cfattach by name.
    687  */
    688 static struct cfattach *
    689 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
    690 {
    691 	struct cfattach *ca;
    692 
    693 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
    694 		if (STREQ(ca->ca_name, atname))
    695 			return ca;
    696 	}
    697 
    698 	return NULL;
    699 }
    700 
    701 /*
    702  * Look up a cfattach by driver/attachment name.
    703  */
    704 struct cfattach *
    705 config_cfattach_lookup(const char *name, const char *atname)
    706 {
    707 	struct cfdriver *cd;
    708 
    709 	cd = config_cfdriver_lookup(name);
    710 	if (cd == NULL)
    711 		return NULL;
    712 
    713 	return config_cfattach_lookup_cd(cd, atname);
    714 }
    715 
    716 /*
    717  * Apply the matching function and choose the best.  This is used
    718  * a few times and we want to keep the code small.
    719  */
    720 static void
    721 mapply(struct matchinfo *m, cfdata_t cf)
    722 {
    723 	int pri;
    724 
    725 	if (m->fn != NULL) {
    726 		pri = (*m->fn)(m->parent, cf, m->locs, m->aux);
    727 	} else {
    728 		pri = config_match(m->parent, cf, m->aux);
    729 	}
    730 	if (pri > m->pri) {
    731 		m->match = cf;
    732 		m->pri = pri;
    733 	}
    734 }
    735 
    736 int
    737 config_stdsubmatch(device_t parent, cfdata_t cf, const int *locs, void *aux)
    738 {
    739 	const struct cfiattrdata *ci;
    740 	const struct cflocdesc *cl;
    741 	int nlocs, i;
    742 
    743 	ci = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
    744 	KASSERT(ci);
    745 	nlocs = ci->ci_loclen;
    746 	KASSERT(!nlocs || locs);
    747 	for (i = 0; i < nlocs; i++) {
    748 		cl = &ci->ci_locdesc[i];
    749 		if (cl->cld_defaultstr != NULL &&
    750 		    cf->cf_loc[i] == cl->cld_default)
    751 			continue;
    752 		if (cf->cf_loc[i] == locs[i])
    753 			continue;
    754 		return 0;
    755 	}
    756 
    757 	return config_match(parent, cf, aux);
    758 }
    759 
    760 /*
    761  * Helper function: check whether the driver supports the interface attribute
    762  * and return its descriptor structure.
    763  */
    764 static const struct cfiattrdata *
    765 cfdriver_get_iattr(const struct cfdriver *cd, const char *ia)
    766 {
    767 	const struct cfiattrdata * const *cpp;
    768 
    769 	if (cd->cd_attrs == NULL)
    770 		return 0;
    771 
    772 	for (cpp = cd->cd_attrs; *cpp; cpp++) {
    773 		if (STREQ((*cpp)->ci_name, ia)) {
    774 			/* Match. */
    775 			return *cpp;
    776 		}
    777 	}
    778 	return 0;
    779 }
    780 
    781 /*
    782  * Lookup an interface attribute description by name.
    783  * If the driver is given, consider only its supported attributes.
    784  */
    785 const struct cfiattrdata *
    786 cfiattr_lookup(const char *name, const struct cfdriver *cd)
    787 {
    788 	const struct cfdriver *d;
    789 	const struct cfiattrdata *ia;
    790 
    791 	if (cd)
    792 		return cfdriver_get_iattr(cd, name);
    793 
    794 	LIST_FOREACH(d, &allcfdrivers, cd_list) {
    795 		ia = cfdriver_get_iattr(d, name);
    796 		if (ia)
    797 			return ia;
    798 	}
    799 	return 0;
    800 }
    801 
    802 /*
    803  * Determine if `parent' is a potential parent for a device spec based
    804  * on `cfp'.
    805  */
    806 static int
    807 cfparent_match(const device_t parent, const struct cfparent *cfp)
    808 {
    809 	struct cfdriver *pcd;
    810 
    811 	/* We don't match root nodes here. */
    812 	if (cfp == NULL)
    813 		return 0;
    814 
    815 	pcd = parent->dv_cfdriver;
    816 	KASSERT(pcd != NULL);
    817 
    818 	/*
    819 	 * First, ensure this parent has the correct interface
    820 	 * attribute.
    821 	 */
    822 	if (!cfdriver_get_iattr(pcd, cfp->cfp_iattr))
    823 		return 0;
    824 
    825 	/*
    826 	 * If no specific parent device instance was specified (i.e.
    827 	 * we're attaching to the attribute only), we're done!
    828 	 */
    829 	if (cfp->cfp_parent == NULL)
    830 		return 1;
    831 
    832 	/*
    833 	 * Check the parent device's name.
    834 	 */
    835 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
    836 		return 0;	/* not the same parent */
    837 
    838 	/*
    839 	 * Make sure the unit number matches.
    840 	 */
    841 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
    842 	    cfp->cfp_unit == parent->dv_unit)
    843 		return 1;
    844 
    845 	/* Unit numbers don't match. */
    846 	return 0;
    847 }
    848 
    849 /*
    850  * Helper for config_cfdata_attach(): check all devices whether it could be
    851  * parent any attachment in the config data table passed, and rescan.
    852  */
    853 static void
    854 rescan_with_cfdata(const struct cfdata *cf)
    855 {
    856 	device_t d;
    857 	const struct cfdata *cf1;
    858 	deviter_t di;
    859 
    860 
    861 	/*
    862 	 * "alldevs" is likely longer than a modules's cfdata, so make it
    863 	 * the outer loop.
    864 	 */
    865 	for (d = deviter_first(&di, 0); d != NULL; d = deviter_next(&di)) {
    866 
    867 		if (!(d->dv_cfattach->ca_rescan))
    868 			continue;
    869 
    870 		for (cf1 = cf; cf1->cf_name; cf1++) {
    871 
    872 			if (!cfparent_match(d, cf1->cf_pspec))
    873 				continue;
    874 
    875 			(*d->dv_cfattach->ca_rescan)(d,
    876 				cfdata_ifattr(cf1), cf1->cf_loc);
    877 
    878 			config_deferred(d);
    879 		}
    880 	}
    881 	deviter_release(&di);
    882 }
    883 
    884 /*
    885  * Attach a supplemental config data table and rescan potential
    886  * parent devices if required.
    887  */
    888 int
    889 config_cfdata_attach(cfdata_t cf, int scannow)
    890 {
    891 	struct cftable *ct;
    892 
    893 	ct = kmem_alloc(sizeof(*ct), KM_SLEEP);
    894 	ct->ct_cfdata = cf;
    895 	TAILQ_INSERT_TAIL(&allcftables, ct, ct_list);
    896 
    897 	if (scannow)
    898 		rescan_with_cfdata(cf);
    899 
    900 	return 0;
    901 }
    902 
    903 /*
    904  * Helper for config_cfdata_detach: check whether a device is
    905  * found through any attachment in the config data table.
    906  */
    907 static int
    908 dev_in_cfdata(device_t d, cfdata_t cf)
    909 {
    910 	const struct cfdata *cf1;
    911 
    912 	for (cf1 = cf; cf1->cf_name; cf1++)
    913 		if (d->dv_cfdata == cf1)
    914 			return 1;
    915 
    916 	return 0;
    917 }
    918 
    919 /*
    920  * Detach a supplemental config data table. Detach all devices found
    921  * through that table (and thus keeping references to it) before.
    922  */
    923 int
    924 config_cfdata_detach(cfdata_t cf)
    925 {
    926 	device_t d;
    927 	int error = 0;
    928 	struct cftable *ct;
    929 	deviter_t di;
    930 
    931 	for (d = deviter_first(&di, DEVITER_F_RW); d != NULL;
    932 	     d = deviter_next(&di)) {
    933 		if (!dev_in_cfdata(d, cf))
    934 			continue;
    935 		if ((error = config_detach(d, 0)) != 0)
    936 			break;
    937 	}
    938 	deviter_release(&di);
    939 	if (error) {
    940 		aprint_error_dev(d, "unable to detach instance\n");
    941 		return error;
    942 	}
    943 
    944 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
    945 		if (ct->ct_cfdata == cf) {
    946 			TAILQ_REMOVE(&allcftables, ct, ct_list);
    947 			kmem_free(ct, sizeof(*ct));
    948 			return 0;
    949 		}
    950 	}
    951 
    952 	/* not found -- shouldn't happen */
    953 	return EINVAL;
    954 }
    955 
    956 /*
    957  * Invoke the "match" routine for a cfdata entry on behalf of
    958  * an external caller, usually a "submatch" routine.
    959  */
    960 int
    961 config_match(device_t parent, cfdata_t cf, void *aux)
    962 {
    963 	struct cfattach *ca;
    964 
    965 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
    966 	if (ca == NULL) {
    967 		/* No attachment for this entry, oh well. */
    968 		return 0;
    969 	}
    970 
    971 	return (*ca->ca_match)(parent, cf, aux);
    972 }
    973 
    974 /*
    975  * Iterate over all potential children of some device, calling the given
    976  * function (default being the child's match function) for each one.
    977  * Nonzero returns are matches; the highest value returned is considered
    978  * the best match.  Return the `found child' if we got a match, or NULL
    979  * otherwise.  The `aux' pointer is simply passed on through.
    980  *
    981  * Note that this function is designed so that it can be used to apply
    982  * an arbitrary function to all potential children (its return value
    983  * can be ignored).
    984  */
    985 cfdata_t
    986 config_search_loc(cfsubmatch_t fn, device_t parent,
    987 		  const char *ifattr, const int *locs, void *aux)
    988 {
    989 	struct cftable *ct;
    990 	cfdata_t cf;
    991 	struct matchinfo m;
    992 
    993 	KASSERT(config_initialized);
    994 	KASSERT(!ifattr || cfdriver_get_iattr(parent->dv_cfdriver, ifattr));
    995 
    996 	m.fn = fn;
    997 	m.parent = parent;
    998 	m.locs = locs;
    999 	m.aux = aux;
   1000 	m.match = NULL;
   1001 	m.pri = 0;
   1002 
   1003 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
   1004 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
   1005 
   1006 			/* We don't match root nodes here. */
   1007 			if (!cf->cf_pspec)
   1008 				continue;
   1009 
   1010 			/*
   1011 			 * Skip cf if no longer eligible, otherwise scan
   1012 			 * through parents for one matching `parent', and
   1013 			 * try match function.
   1014 			 */
   1015 			if (cf->cf_fstate == FSTATE_FOUND)
   1016 				continue;
   1017 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
   1018 			    cf->cf_fstate == FSTATE_DSTAR)
   1019 				continue;
   1020 
   1021 			/*
   1022 			 * If an interface attribute was specified,
   1023 			 * consider only children which attach to
   1024 			 * that attribute.
   1025 			 */
   1026 			if (ifattr && !STREQ(ifattr, cfdata_ifattr(cf)))
   1027 				continue;
   1028 
   1029 			if (cfparent_match(parent, cf->cf_pspec))
   1030 				mapply(&m, cf);
   1031 		}
   1032 	}
   1033 	return m.match;
   1034 }
   1035 
   1036 cfdata_t
   1037 config_search_ia(cfsubmatch_t fn, device_t parent, const char *ifattr,
   1038     void *aux)
   1039 {
   1040 
   1041 	return config_search_loc(fn, parent, ifattr, NULL, aux);
   1042 }
   1043 
   1044 /*
   1045  * Find the given root device.
   1046  * This is much like config_search, but there is no parent.
   1047  * Don't bother with multiple cfdata tables; the root node
   1048  * must always be in the initial table.
   1049  */
   1050 cfdata_t
   1051 config_rootsearch(cfsubmatch_t fn, const char *rootname, void *aux)
   1052 {
   1053 	cfdata_t cf;
   1054 	const short *p;
   1055 	struct matchinfo m;
   1056 
   1057 	m.fn = fn;
   1058 	m.parent = ROOT;
   1059 	m.aux = aux;
   1060 	m.match = NULL;
   1061 	m.pri = 0;
   1062 	m.locs = 0;
   1063 	/*
   1064 	 * Look at root entries for matching name.  We do not bother
   1065 	 * with found-state here since only one root should ever be
   1066 	 * searched (and it must be done first).
   1067 	 */
   1068 	for (p = cfroots; *p >= 0; p++) {
   1069 		cf = &cfdata[*p];
   1070 		if (strcmp(cf->cf_name, rootname) == 0)
   1071 			mapply(&m, cf);
   1072 	}
   1073 	return m.match;
   1074 }
   1075 
   1076 static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
   1077 
   1078 /*
   1079  * The given `aux' argument describes a device that has been found
   1080  * on the given parent, but not necessarily configured.  Locate the
   1081  * configuration data for that device (using the submatch function
   1082  * provided, or using candidates' cd_match configuration driver
   1083  * functions) and attach it, and return its device_t.  If the device was
   1084  * not configured, call the given `print' function and return NULL.
   1085  */
   1086 device_t
   1087 config_found_sm_loc(device_t parent,
   1088 		const char *ifattr, const int *locs, void *aux,
   1089 		cfprint_t print, cfsubmatch_t submatch)
   1090 {
   1091 	cfdata_t cf;
   1092 
   1093 	if ((cf = config_search_loc(submatch, parent, ifattr, locs, aux)))
   1094 		return(config_attach_loc(parent, cf, locs, aux, print));
   1095 	if (print) {
   1096 		if (config_do_twiddle && cold)
   1097 			twiddle();
   1098 		aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
   1099 	}
   1100 
   1101 	/*
   1102 	 * This has the effect of mixing in a single timestamp to the
   1103 	 * entropy pool.  Experiments indicate the estimator will almost
   1104 	 * always attribute one bit of entropy to this sample; analysis
   1105 	 * of device attach/detach timestamps on FreeBSD indicates 4
   1106 	 * bits of entropy/sample so this seems appropriately conservative.
   1107 	 */
   1108 	rnd_add_uint32(&rnd_autoconf_source, 0);
   1109 	return NULL;
   1110 }
   1111 
   1112 device_t
   1113 config_found_ia(device_t parent, const char *ifattr, void *aux,
   1114     cfprint_t print)
   1115 {
   1116 
   1117 	return config_found_sm_loc(parent, ifattr, NULL, aux, print, NULL);
   1118 }
   1119 
   1120 device_t
   1121 config_found(device_t parent, void *aux, cfprint_t print)
   1122 {
   1123 
   1124 	return config_found_sm_loc(parent, NULL, NULL, aux, print, NULL);
   1125 }
   1126 
   1127 /*
   1128  * As above, but for root devices.
   1129  */
   1130 device_t
   1131 config_rootfound(const char *rootname, void *aux)
   1132 {
   1133 	cfdata_t cf;
   1134 
   1135 	if ((cf = config_rootsearch(NULL, rootname, aux)) != NULL)
   1136 		return config_attach(ROOT, cf, aux, NULL);
   1137 	aprint_error("root device %s not configured\n", rootname);
   1138 	return NULL;
   1139 }
   1140 
   1141 /* just like sprintf(buf, "%d") except that it works from the end */
   1142 static char *
   1143 number(char *ep, int n)
   1144 {
   1145 
   1146 	*--ep = 0;
   1147 	while (n >= 10) {
   1148 		*--ep = (n % 10) + '0';
   1149 		n /= 10;
   1150 	}
   1151 	*--ep = n + '0';
   1152 	return ep;
   1153 }
   1154 
   1155 /*
   1156  * Expand the size of the cd_devs array if necessary.
   1157  *
   1158  * The caller must hold alldevs_lock. config_makeroom() may release and
   1159  * re-acquire alldevs_lock, so callers should re-check conditions such
   1160  * as alldevs_nwrite == 0 and alldevs_nread == 0 when config_makeroom()
   1161  * returns.
   1162  */
   1163 static void
   1164 config_makeroom(int n, struct cfdriver *cd)
   1165 {
   1166 	int ondevs, nndevs;
   1167 	device_t *osp, *nsp;
   1168 
   1169 	KASSERT(mutex_owned(&alldevs_lock));
   1170 	alldevs_nwrite++;
   1171 
   1172 	for (nndevs = MAX(4, cd->cd_ndevs); nndevs <= n; nndevs += nndevs)
   1173 		;
   1174 
   1175 	while (n >= cd->cd_ndevs) {
   1176 		/*
   1177 		 * Need to expand the array.
   1178 		 */
   1179 		ondevs = cd->cd_ndevs;
   1180 		osp = cd->cd_devs;
   1181 
   1182 		/*
   1183 		 * Release alldevs_lock around allocation, which may
   1184 		 * sleep.
   1185 		 */
   1186 		mutex_exit(&alldevs_lock);
   1187 		nsp = kmem_alloc(sizeof(device_t[nndevs]), KM_SLEEP);
   1188 		mutex_enter(&alldevs_lock);
   1189 
   1190 		/*
   1191 		 * If another thread moved the array while we did
   1192 		 * not hold alldevs_lock, try again.
   1193 		 */
   1194 		if (cd->cd_devs != osp) {
   1195 			mutex_exit(&alldevs_lock);
   1196 			kmem_free(nsp, sizeof(device_t[nndevs]));
   1197 			mutex_enter(&alldevs_lock);
   1198 			continue;
   1199 		}
   1200 
   1201 		memset(nsp + ondevs, 0, sizeof(device_t[nndevs - ondevs]));
   1202 		if (ondevs != 0)
   1203 			memcpy(nsp, cd->cd_devs, sizeof(device_t[ondevs]));
   1204 
   1205 		cd->cd_ndevs = nndevs;
   1206 		cd->cd_devs = nsp;
   1207 		if (ondevs != 0) {
   1208 			mutex_exit(&alldevs_lock);
   1209 			kmem_free(osp, sizeof(device_t[ondevs]));
   1210 			mutex_enter(&alldevs_lock);
   1211 		}
   1212 	}
   1213 	KASSERT(mutex_owned(&alldevs_lock));
   1214 	alldevs_nwrite--;
   1215 }
   1216 
   1217 /*
   1218  * Put dev into the devices list.
   1219  */
   1220 static void
   1221 config_devlink(device_t dev)
   1222 {
   1223 
   1224 	mutex_enter(&alldevs_lock);
   1225 
   1226 	KASSERT(device_cfdriver(dev)->cd_devs[dev->dv_unit] == dev);
   1227 
   1228 	dev->dv_add_gen = alldevs_gen;
   1229 	/* It is safe to add a device to the tail of the list while
   1230 	 * readers and writers are in the list.
   1231 	 */
   1232 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);
   1233 	mutex_exit(&alldevs_lock);
   1234 }
   1235 
   1236 static void
   1237 config_devfree(device_t dev)
   1238 {
   1239 	int priv = (dev->dv_flags & DVF_PRIV_ALLOC);
   1240 
   1241 	if (dev->dv_cfattach->ca_devsize > 0)
   1242 		kmem_free(dev->dv_private, dev->dv_cfattach->ca_devsize);
   1243 	if (priv)
   1244 		kmem_free(dev, sizeof(*dev));
   1245 }
   1246 
   1247 /*
   1248  * Caller must hold alldevs_lock.
   1249  */
   1250 static void
   1251 config_devunlink(device_t dev, struct devicelist *garbage)
   1252 {
   1253 	struct device_garbage *dg = &dev->dv_garbage;
   1254 	cfdriver_t cd = device_cfdriver(dev);
   1255 	int i;
   1256 
   1257 	KASSERT(mutex_owned(&alldevs_lock));
   1258 
   1259  	/* Unlink from device list.  Link to garbage list. */
   1260 	TAILQ_REMOVE(&alldevs, dev, dv_list);
   1261 	TAILQ_INSERT_TAIL(garbage, dev, dv_list);
   1262 
   1263 	/* Remove from cfdriver's array. */
   1264 	cd->cd_devs[dev->dv_unit] = NULL;
   1265 
   1266 	/*
   1267 	 * If the device now has no units in use, unlink its softc array.
   1268 	 */
   1269 	for (i = 0; i < cd->cd_ndevs; i++) {
   1270 		if (cd->cd_devs[i] != NULL)
   1271 			break;
   1272 	}
   1273 	/* Nothing found.  Unlink, now.  Deallocate, later. */
   1274 	if (i == cd->cd_ndevs) {
   1275 		dg->dg_ndevs = cd->cd_ndevs;
   1276 		dg->dg_devs = cd->cd_devs;
   1277 		cd->cd_devs = NULL;
   1278 		cd->cd_ndevs = 0;
   1279 	}
   1280 }
   1281 
   1282 static void
   1283 config_devdelete(device_t dev)
   1284 {
   1285 	struct device_garbage *dg = &dev->dv_garbage;
   1286 	device_lock_t dvl = device_getlock(dev);
   1287 
   1288 	if (dg->dg_devs != NULL)
   1289 		kmem_free(dg->dg_devs, sizeof(device_t[dg->dg_ndevs]));
   1290 
   1291 	cv_destroy(&dvl->dvl_cv);
   1292 	mutex_destroy(&dvl->dvl_mtx);
   1293 
   1294 	KASSERT(dev->dv_properties != NULL);
   1295 	prop_object_release(dev->dv_properties);
   1296 
   1297 	if (dev->dv_activity_handlers)
   1298 		panic("%s with registered handlers", __func__);
   1299 
   1300 	if (dev->dv_locators) {
   1301 		size_t amount = *--dev->dv_locators;
   1302 		kmem_free(dev->dv_locators, amount);
   1303 	}
   1304 
   1305 	config_devfree(dev);
   1306 }
   1307 
   1308 static int
   1309 config_unit_nextfree(cfdriver_t cd, cfdata_t cf)
   1310 {
   1311 	int unit;
   1312 
   1313 	if (cf->cf_fstate == FSTATE_STAR) {
   1314 		for (unit = cf->cf_unit; unit < cd->cd_ndevs; unit++)
   1315 			if (cd->cd_devs[unit] == NULL)
   1316 				break;
   1317 		/*
   1318 		 * unit is now the unit of the first NULL device pointer,
   1319 		 * or max(cd->cd_ndevs,cf->cf_unit).
   1320 		 */
   1321 	} else {
   1322 		unit = cf->cf_unit;
   1323 		if (unit < cd->cd_ndevs && cd->cd_devs[unit] != NULL)
   1324 			unit = -1;
   1325 	}
   1326 	return unit;
   1327 }
   1328 
   1329 static int
   1330 config_unit_alloc(device_t dev, cfdriver_t cd, cfdata_t cf)
   1331 {
   1332 	struct alldevs_foray af;
   1333 	int unit;
   1334 
   1335 	config_alldevs_enter(&af);
   1336 	for (;;) {
   1337 		unit = config_unit_nextfree(cd, cf);
   1338 		if (unit == -1)
   1339 			break;
   1340 		if (unit < cd->cd_ndevs) {
   1341 			cd->cd_devs[unit] = dev;
   1342 			dev->dv_unit = unit;
   1343 			break;
   1344 		}
   1345 		config_makeroom(unit, cd);
   1346 	}
   1347 	config_alldevs_exit(&af);
   1348 
   1349 	return unit;
   1350 }
   1351 
   1352 static device_t
   1353 config_devalloc(const device_t parent, const cfdata_t cf, const int *locs)
   1354 {
   1355 	cfdriver_t cd;
   1356 	cfattach_t ca;
   1357 	size_t lname, lunit;
   1358 	const char *xunit;
   1359 	int myunit;
   1360 	char num[10];
   1361 	device_t dev;
   1362 	void *dev_private;
   1363 	const struct cfiattrdata *ia;
   1364 	device_lock_t dvl;
   1365 
   1366 	cd = config_cfdriver_lookup(cf->cf_name);
   1367 	if (cd == NULL)
   1368 		return NULL;
   1369 
   1370 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
   1371 	if (ca == NULL)
   1372 		return NULL;
   1373 
   1374 	/* get memory for all device vars */
   1375 	KASSERTMSG((ca->ca_flags & DVF_PRIV_ALLOC)
   1376 	    || ca->ca_devsize >= sizeof(struct device),
   1377 	    "%s: %s (%zu < %zu)", __func__, cf->cf_atname, ca->ca_devsize,
   1378 	    sizeof(struct device));
   1379 	if (ca->ca_devsize > 0) {
   1380 		dev_private = kmem_zalloc(ca->ca_devsize, KM_SLEEP);
   1381 	} else {
   1382 		KASSERT(ca->ca_flags & DVF_PRIV_ALLOC);
   1383 		dev_private = NULL;
   1384 	}
   1385 
   1386 	if ((ca->ca_flags & DVF_PRIV_ALLOC) != 0) {
   1387 		dev = kmem_zalloc(sizeof(*dev), KM_SLEEP);
   1388 	} else {
   1389 		dev = dev_private;
   1390 #ifdef DIAGNOSTIC
   1391 		printf("%s has not been converted to device_t\n", cd->cd_name);
   1392 #endif
   1393 		KASSERT(dev != NULL);
   1394 	}
   1395 	dev->dv_class = cd->cd_class;
   1396 	dev->dv_cfdata = cf;
   1397 	dev->dv_cfdriver = cd;
   1398 	dev->dv_cfattach = ca;
   1399 	dev->dv_activity_count = 0;
   1400 	dev->dv_activity_handlers = NULL;
   1401 	dev->dv_private = dev_private;
   1402 	dev->dv_flags = ca->ca_flags;	/* inherit flags from class */
   1403 
   1404 	myunit = config_unit_alloc(dev, cd, cf);
   1405 	if (myunit == -1) {
   1406 		config_devfree(dev);
   1407 		return NULL;
   1408 	}
   1409 
   1410 	/* compute length of name and decimal expansion of unit number */
   1411 	lname = strlen(cd->cd_name);
   1412 	xunit = number(&num[sizeof(num)], myunit);
   1413 	lunit = &num[sizeof(num)] - xunit;
   1414 	if (lname + lunit > sizeof(dev->dv_xname))
   1415 		panic("config_devalloc: device name too long");
   1416 
   1417 	dvl = device_getlock(dev);
   1418 
   1419 	mutex_init(&dvl->dvl_mtx, MUTEX_DEFAULT, IPL_NONE);
   1420 	cv_init(&dvl->dvl_cv, "pmfsusp");
   1421 
   1422 	memcpy(dev->dv_xname, cd->cd_name, lname);
   1423 	memcpy(dev->dv_xname + lname, xunit, lunit);
   1424 	dev->dv_parent = parent;
   1425 	if (parent != NULL)
   1426 		dev->dv_depth = parent->dv_depth + 1;
   1427 	else
   1428 		dev->dv_depth = 0;
   1429 	dev->dv_flags |= DVF_ACTIVE;	/* always initially active */
   1430 	if (locs) {
   1431 		KASSERT(parent); /* no locators at root */
   1432 		ia = cfiattr_lookup(cfdata_ifattr(cf), parent->dv_cfdriver);
   1433 		dev->dv_locators =
   1434 		    kmem_alloc(sizeof(int [ia->ci_loclen + 1]), KM_SLEEP);
   1435 		*dev->dv_locators++ = sizeof(int [ia->ci_loclen + 1]);
   1436 		memcpy(dev->dv_locators, locs, sizeof(int [ia->ci_loclen]));
   1437 	}
   1438 	dev->dv_properties = prop_dictionary_create();
   1439 	KASSERT(dev->dv_properties != NULL);
   1440 
   1441 	prop_dictionary_set_cstring_nocopy(dev->dv_properties,
   1442 	    "device-driver", dev->dv_cfdriver->cd_name);
   1443 	prop_dictionary_set_uint16(dev->dv_properties,
   1444 	    "device-unit", dev->dv_unit);
   1445 	if (parent != NULL) {
   1446 		prop_dictionary_set_cstring(dev->dv_properties,
   1447 		    "device-parent", device_xname(parent));
   1448 	}
   1449 
   1450 	if (dev->dv_cfdriver->cd_attrs != NULL)
   1451 		config_add_attrib_dict(dev);
   1452 
   1453 	return dev;
   1454 }
   1455 
   1456 /*
   1457  * Create an array of device attach attributes and add it
   1458  * to the device's dv_properties dictionary.
   1459  *
   1460  * <key>interface-attributes</key>
   1461  * <array>
   1462  *    <dict>
   1463  *       <key>attribute-name</key>
   1464  *       <string>foo</string>
   1465  *       <key>locators</key>
   1466  *       <array>
   1467  *          <dict>
   1468  *             <key>loc-name</key>
   1469  *             <string>foo-loc1</string>
   1470  *          </dict>
   1471  *          <dict>
   1472  *             <key>loc-name</key>
   1473  *             <string>foo-loc2</string>
   1474  *             <key>default</key>
   1475  *             <string>foo-loc2-default</string>
   1476  *          </dict>
   1477  *          ...
   1478  *       </array>
   1479  *    </dict>
   1480  *    ...
   1481  * </array>
   1482  */
   1483 
   1484 static void
   1485 config_add_attrib_dict(device_t dev)
   1486 {
   1487 	int i, j;
   1488 	const struct cfiattrdata *ci;
   1489 	prop_dictionary_t attr_dict, loc_dict;
   1490 	prop_array_t attr_array, loc_array;
   1491 
   1492 	if ((attr_array = prop_array_create()) == NULL)
   1493 		return;
   1494 
   1495 	for (i = 0; ; i++) {
   1496 		if ((ci = dev->dv_cfdriver->cd_attrs[i]) == NULL)
   1497 			break;
   1498 		if ((attr_dict = prop_dictionary_create()) == NULL)
   1499 			break;
   1500 		prop_dictionary_set_cstring_nocopy(attr_dict, "attribute-name",
   1501 		    ci->ci_name);
   1502 
   1503 		/* Create an array of the locator names and defaults */
   1504 
   1505 		if (ci->ci_loclen != 0 &&
   1506 		    (loc_array = prop_array_create()) != NULL) {
   1507 			for (j = 0; j < ci->ci_loclen; j++) {
   1508 				loc_dict = prop_dictionary_create();
   1509 				if (loc_dict == NULL)
   1510 					continue;
   1511 				prop_dictionary_set_cstring_nocopy(loc_dict,
   1512 				    "loc-name", ci->ci_locdesc[j].cld_name);
   1513 				if (ci->ci_locdesc[j].cld_defaultstr != NULL)
   1514 					prop_dictionary_set_cstring_nocopy(
   1515 					    loc_dict, "default",
   1516 					    ci->ci_locdesc[j].cld_defaultstr);
   1517 				prop_array_set(loc_array, j, loc_dict);
   1518 				prop_object_release(loc_dict);
   1519 			}
   1520 			prop_dictionary_set_and_rel(attr_dict, "locators",
   1521 			    loc_array);
   1522 		}
   1523 		prop_array_add(attr_array, attr_dict);
   1524 		prop_object_release(attr_dict);
   1525 	}
   1526 	if (i == 0)
   1527 		prop_object_release(attr_array);
   1528 	else
   1529 		prop_dictionary_set_and_rel(dev->dv_properties,
   1530 		    "interface-attributes", attr_array);
   1531 
   1532 	return;
   1533 }
   1534 
   1535 /*
   1536  * Attach a found device.
   1537  */
   1538 device_t
   1539 config_attach_loc(device_t parent, cfdata_t cf,
   1540 	const int *locs, void *aux, cfprint_t print)
   1541 {
   1542 	device_t dev;
   1543 	struct cftable *ct;
   1544 	const char *drvname;
   1545 
   1546 	dev = config_devalloc(parent, cf, locs);
   1547 	if (!dev)
   1548 		panic("config_attach: allocation of device softc failed");
   1549 
   1550 	/* XXX redundant - see below? */
   1551 	if (cf->cf_fstate != FSTATE_STAR) {
   1552 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
   1553 		cf->cf_fstate = FSTATE_FOUND;
   1554 	}
   1555 
   1556 	config_devlink(dev);
   1557 
   1558 	if (config_do_twiddle && cold)
   1559 		twiddle();
   1560 	else
   1561 		aprint_naive("Found ");
   1562 	/*
   1563 	 * We want the next two printfs for normal, verbose, and quiet,
   1564 	 * but not silent (in which case, we're twiddling, instead).
   1565 	 */
   1566 	if (parent == ROOT) {
   1567 		aprint_naive("%s (root)", device_xname(dev));
   1568 		aprint_normal("%s (root)", device_xname(dev));
   1569 	} else {
   1570 		aprint_naive("%s at %s", device_xname(dev),
   1571 		    device_xname(parent));
   1572 		aprint_normal("%s at %s", device_xname(dev),
   1573 		    device_xname(parent));
   1574 		if (print)
   1575 			(void) (*print)(aux, NULL);
   1576 	}
   1577 
   1578 	/*
   1579 	 * Before attaching, clobber any unfound devices that are
   1580 	 * otherwise identical.
   1581 	 * XXX code above is redundant?
   1582 	 */
   1583 	drvname = dev->dv_cfdriver->cd_name;
   1584 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
   1585 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
   1586 			if (STREQ(cf->cf_name, drvname) &&
   1587 			    cf->cf_unit == dev->dv_unit) {
   1588 				if (cf->cf_fstate == FSTATE_NOTFOUND)
   1589 					cf->cf_fstate = FSTATE_FOUND;
   1590 			}
   1591 		}
   1592 	}
   1593 	device_register(dev, aux);
   1594 
   1595 	/* Let userland know */
   1596 	devmon_report_device(dev, true);
   1597 
   1598 	(*dev->dv_cfattach->ca_attach)(parent, dev, aux);
   1599 
   1600 	if (!device_pmf_is_registered(dev))
   1601 		aprint_debug_dev(dev, "WARNING: power management not "
   1602 		    "supported\n");
   1603 
   1604 	config_process_deferred(&deferred_config_queue, dev);
   1605 
   1606 	device_register_post_config(dev, aux);
   1607 	return dev;
   1608 }
   1609 
   1610 device_t
   1611 config_attach(device_t parent, cfdata_t cf, void *aux, cfprint_t print)
   1612 {
   1613 
   1614 	return config_attach_loc(parent, cf, NULL, aux, print);
   1615 }
   1616 
   1617 /*
   1618  * As above, but for pseudo-devices.  Pseudo-devices attached in this
   1619  * way are silently inserted into the device tree, and their children
   1620  * attached.
   1621  *
   1622  * Note that because pseudo-devices are attached silently, any information
   1623  * the attach routine wishes to print should be prefixed with the device
   1624  * name by the attach routine.
   1625  */
   1626 device_t
   1627 config_attach_pseudo(cfdata_t cf)
   1628 {
   1629 	device_t dev;
   1630 
   1631 	dev = config_devalloc(ROOT, cf, NULL);
   1632 	if (!dev)
   1633 		return NULL;
   1634 
   1635 	/* XXX mark busy in cfdata */
   1636 
   1637 	if (cf->cf_fstate != FSTATE_STAR) {
   1638 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
   1639 		cf->cf_fstate = FSTATE_FOUND;
   1640 	}
   1641 
   1642 	config_devlink(dev);
   1643 
   1644 #if 0	/* XXXJRT not yet */
   1645 	device_register(dev, NULL);	/* like a root node */
   1646 #endif
   1647 
   1648 	/* Let userland know */
   1649 	devmon_report_device(dev, true);
   1650 
   1651 	(*dev->dv_cfattach->ca_attach)(ROOT, dev, NULL);
   1652 
   1653 	config_process_deferred(&deferred_config_queue, dev);
   1654 	return dev;
   1655 }
   1656 
   1657 /*
   1658  * Caller must hold alldevs_lock.
   1659  */
   1660 static void
   1661 config_collect_garbage(struct devicelist *garbage)
   1662 {
   1663 	device_t dv;
   1664 
   1665 	KASSERT(!cpu_intr_p());
   1666 	KASSERT(!cpu_softintr_p());
   1667 	KASSERT(mutex_owned(&alldevs_lock));
   1668 
   1669 	while (alldevs_nwrite == 0 && alldevs_nread == 0 && alldevs_garbage) {
   1670 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   1671 			if (dv->dv_del_gen != 0)
   1672 				break;
   1673 		}
   1674 		if (dv == NULL) {
   1675 			alldevs_garbage = false;
   1676 			break;
   1677 		}
   1678 		config_devunlink(dv, garbage);
   1679 	}
   1680 	KASSERT(mutex_owned(&alldevs_lock));
   1681 }
   1682 
   1683 static void
   1684 config_dump_garbage(struct devicelist *garbage)
   1685 {
   1686 	device_t dv;
   1687 
   1688 	while ((dv = TAILQ_FIRST(garbage)) != NULL) {
   1689 		TAILQ_REMOVE(garbage, dv, dv_list);
   1690 		config_devdelete(dv);
   1691 	}
   1692 }
   1693 
   1694 /*
   1695  * Detach a device.  Optionally forced (e.g. because of hardware
   1696  * removal) and quiet.  Returns zero if successful, non-zero
   1697  * (an error code) otherwise.
   1698  *
   1699  * Note that this code wants to be run from a process context, so
   1700  * that the detach can sleep to allow processes which have a device
   1701  * open to run and unwind their stacks.
   1702  */
   1703 int
   1704 config_detach(device_t dev, int flags)
   1705 {
   1706 	struct alldevs_foray af;
   1707 	struct cftable *ct;
   1708 	cfdata_t cf;
   1709 	const struct cfattach *ca;
   1710 	struct cfdriver *cd;
   1711 	device_t d __diagused;
   1712 	int rv = 0;
   1713 
   1714 	cf = dev->dv_cfdata;
   1715 	KASSERTMSG((cf == NULL || cf->cf_fstate == FSTATE_FOUND ||
   1716 		cf->cf_fstate == FSTATE_STAR),
   1717 	    "config_detach: %s: bad device fstate: %d",
   1718 	    device_xname(dev), cf ? cf->cf_fstate : -1);
   1719 
   1720 	cd = dev->dv_cfdriver;
   1721 	KASSERT(cd != NULL);
   1722 
   1723 	ca = dev->dv_cfattach;
   1724 	KASSERT(ca != NULL);
   1725 
   1726 	mutex_enter(&alldevs_lock);
   1727 	if (dev->dv_del_gen != 0) {
   1728 		mutex_exit(&alldevs_lock);
   1729 #ifdef DIAGNOSTIC
   1730 		printf("%s: %s is already detached\n", __func__,
   1731 		    device_xname(dev));
   1732 #endif /* DIAGNOSTIC */
   1733 		return ENOENT;
   1734 	}
   1735 	alldevs_nwrite++;
   1736 	mutex_exit(&alldevs_lock);
   1737 
   1738 	if (!detachall &&
   1739 	    (flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
   1740 	    (dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
   1741 		rv = EOPNOTSUPP;
   1742 	} else if (ca->ca_detach != NULL) {
   1743 		rv = (*ca->ca_detach)(dev, flags);
   1744 	} else
   1745 		rv = EOPNOTSUPP;
   1746 
   1747 	/*
   1748 	 * If it was not possible to detach the device, then we either
   1749 	 * panic() (for the forced but failed case), or return an error.
   1750 	 *
   1751 	 * If it was possible to detach the device, ensure that the
   1752 	 * device is deactivated.
   1753 	 */
   1754 	if (rv == 0)
   1755 		dev->dv_flags &= ~DVF_ACTIVE;
   1756 	else if ((flags & DETACH_FORCE) == 0)
   1757 		goto out;
   1758 	else {
   1759 		panic("config_detach: forced detach of %s failed (%d)",
   1760 		    device_xname(dev), rv);
   1761 	}
   1762 
   1763 	/*
   1764 	 * The device has now been successfully detached.
   1765 	 */
   1766 
   1767 	/* Let userland know */
   1768 	devmon_report_device(dev, false);
   1769 
   1770 #ifdef DIAGNOSTIC
   1771 	/*
   1772 	 * Sanity: If you're successfully detached, you should have no
   1773 	 * children.  (Note that because children must be attached
   1774 	 * after parents, we only need to search the latter part of
   1775 	 * the list.)
   1776 	 */
   1777 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
   1778 	    d = TAILQ_NEXT(d, dv_list)) {
   1779 		if (d->dv_parent == dev && d->dv_del_gen == 0) {
   1780 			printf("config_detach: detached device %s"
   1781 			    " has children %s\n", device_xname(dev),
   1782 			    device_xname(d));
   1783 			panic("config_detach");
   1784 		}
   1785 	}
   1786 #endif
   1787 
   1788 	/* notify the parent that the child is gone */
   1789 	if (dev->dv_parent) {
   1790 		device_t p = dev->dv_parent;
   1791 		if (p->dv_cfattach->ca_childdetached)
   1792 			(*p->dv_cfattach->ca_childdetached)(p, dev);
   1793 	}
   1794 
   1795 	/*
   1796 	 * Mark cfdata to show that the unit can be reused, if possible.
   1797 	 */
   1798 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
   1799 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
   1800 			if (STREQ(cf->cf_name, cd->cd_name)) {
   1801 				if (cf->cf_fstate == FSTATE_FOUND &&
   1802 				    cf->cf_unit == dev->dv_unit)
   1803 					cf->cf_fstate = FSTATE_NOTFOUND;
   1804 			}
   1805 		}
   1806 	}
   1807 
   1808 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
   1809 		aprint_normal_dev(dev, "detached\n");
   1810 
   1811 out:
   1812 	config_alldevs_enter(&af);
   1813 	KASSERT(alldevs_nwrite != 0);
   1814 	--alldevs_nwrite;
   1815 	if (rv == 0 && dev->dv_del_gen == 0) {
   1816 		if (alldevs_nwrite == 0 && alldevs_nread == 0)
   1817 			config_devunlink(dev, &af.af_garbage);
   1818 		else {
   1819 			dev->dv_del_gen = alldevs_gen;
   1820 			alldevs_garbage = true;
   1821 		}
   1822 	}
   1823 	config_alldevs_exit(&af);
   1824 
   1825 	return rv;
   1826 }
   1827 
   1828 int
   1829 config_detach_children(device_t parent, int flags)
   1830 {
   1831 	device_t dv;
   1832 	deviter_t di;
   1833 	int error = 0;
   1834 
   1835 	for (dv = deviter_first(&di, DEVITER_F_RW); dv != NULL;
   1836 	     dv = deviter_next(&di)) {
   1837 		if (device_parent(dv) != parent)
   1838 			continue;
   1839 		if ((error = config_detach(dv, flags)) != 0)
   1840 			break;
   1841 	}
   1842 	deviter_release(&di);
   1843 	return error;
   1844 }
   1845 
   1846 device_t
   1847 shutdown_first(struct shutdown_state *s)
   1848 {
   1849 	if (!s->initialized) {
   1850 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
   1851 		s->initialized = true;
   1852 	}
   1853 	return shutdown_next(s);
   1854 }
   1855 
   1856 device_t
   1857 shutdown_next(struct shutdown_state *s)
   1858 {
   1859 	device_t dv;
   1860 
   1861 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
   1862 		;
   1863 
   1864 	if (dv == NULL)
   1865 		s->initialized = false;
   1866 
   1867 	return dv;
   1868 }
   1869 
   1870 bool
   1871 config_detach_all(int how)
   1872 {
   1873 	static struct shutdown_state s;
   1874 	device_t curdev;
   1875 	bool progress = false;
   1876 	int flags;
   1877 
   1878 	if ((how & (RB_NOSYNC|RB_DUMP)) != 0)
   1879 		return false;
   1880 
   1881 	if ((how & RB_POWERDOWN) == RB_POWERDOWN)
   1882 		flags = DETACH_SHUTDOWN | DETACH_POWEROFF;
   1883 	else
   1884 		flags = DETACH_SHUTDOWN;
   1885 
   1886 	for (curdev = shutdown_first(&s); curdev != NULL;
   1887 	     curdev = shutdown_next(&s)) {
   1888 		aprint_debug(" detaching %s, ", device_xname(curdev));
   1889 		if (config_detach(curdev, flags) == 0) {
   1890 			progress = true;
   1891 			aprint_debug("success.");
   1892 		} else
   1893 			aprint_debug("failed.");
   1894 	}
   1895 	return progress;
   1896 }
   1897 
   1898 static bool
   1899 device_is_ancestor_of(device_t ancestor, device_t descendant)
   1900 {
   1901 	device_t dv;
   1902 
   1903 	for (dv = descendant; dv != NULL; dv = device_parent(dv)) {
   1904 		if (device_parent(dv) == ancestor)
   1905 			return true;
   1906 	}
   1907 	return false;
   1908 }
   1909 
   1910 int
   1911 config_deactivate(device_t dev)
   1912 {
   1913 	deviter_t di;
   1914 	const struct cfattach *ca;
   1915 	device_t descendant;
   1916 	int s, rv = 0, oflags;
   1917 
   1918 	for (descendant = deviter_first(&di, DEVITER_F_ROOT_FIRST);
   1919 	     descendant != NULL;
   1920 	     descendant = deviter_next(&di)) {
   1921 		if (dev != descendant &&
   1922 		    !device_is_ancestor_of(dev, descendant))
   1923 			continue;
   1924 
   1925 		if ((descendant->dv_flags & DVF_ACTIVE) == 0)
   1926 			continue;
   1927 
   1928 		ca = descendant->dv_cfattach;
   1929 		oflags = descendant->dv_flags;
   1930 
   1931 		descendant->dv_flags &= ~DVF_ACTIVE;
   1932 		if (ca->ca_activate == NULL)
   1933 			continue;
   1934 		s = splhigh();
   1935 		rv = (*ca->ca_activate)(descendant, DVACT_DEACTIVATE);
   1936 		splx(s);
   1937 		if (rv != 0)
   1938 			descendant->dv_flags = oflags;
   1939 	}
   1940 	deviter_release(&di);
   1941 	return rv;
   1942 }
   1943 
   1944 /*
   1945  * Defer the configuration of the specified device until all
   1946  * of its parent's devices have been attached.
   1947  */
   1948 void
   1949 config_defer(device_t dev, void (*func)(device_t))
   1950 {
   1951 	struct deferred_config *dc;
   1952 
   1953 	if (dev->dv_parent == NULL)
   1954 		panic("config_defer: can't defer config of a root device");
   1955 
   1956 #ifdef DIAGNOSTIC
   1957 	TAILQ_FOREACH(dc, &deferred_config_queue, dc_queue) {
   1958 		if (dc->dc_dev == dev)
   1959 			panic("config_defer: deferred twice");
   1960 	}
   1961 #endif
   1962 
   1963 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
   1964 	dc->dc_dev = dev;
   1965 	dc->dc_func = func;
   1966 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
   1967 	config_pending_incr(dev);
   1968 }
   1969 
   1970 /*
   1971  * Defer some autoconfiguration for a device until after interrupts
   1972  * are enabled.
   1973  */
   1974 void
   1975 config_interrupts(device_t dev, void (*func)(device_t))
   1976 {
   1977 	struct deferred_config *dc;
   1978 
   1979 	/*
   1980 	 * If interrupts are enabled, callback now.
   1981 	 */
   1982 	if (cold == 0) {
   1983 		(*func)(dev);
   1984 		return;
   1985 	}
   1986 
   1987 #ifdef DIAGNOSTIC
   1988 	TAILQ_FOREACH(dc, &interrupt_config_queue, dc_queue) {
   1989 		if (dc->dc_dev == dev)
   1990 			panic("config_interrupts: deferred twice");
   1991 	}
   1992 #endif
   1993 
   1994 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
   1995 	dc->dc_dev = dev;
   1996 	dc->dc_func = func;
   1997 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
   1998 	config_pending_incr(dev);
   1999 }
   2000 
   2001 /*
   2002  * Defer some autoconfiguration for a device until after root file system
   2003  * is mounted (to load firmware etc).
   2004  */
   2005 void
   2006 config_mountroot(device_t dev, void (*func)(device_t))
   2007 {
   2008 	struct deferred_config *dc;
   2009 
   2010 	/*
   2011 	 * If root file system is mounted, callback now.
   2012 	 */
   2013 	if (root_is_mounted) {
   2014 		(*func)(dev);
   2015 		return;
   2016 	}
   2017 
   2018 #ifdef DIAGNOSTIC
   2019 	TAILQ_FOREACH(dc, &mountroot_config_queue, dc_queue) {
   2020 		if (dc->dc_dev == dev)
   2021 			panic("%s: deferred twice", __func__);
   2022 	}
   2023 #endif
   2024 
   2025 	dc = kmem_alloc(sizeof(*dc), KM_SLEEP);
   2026 	dc->dc_dev = dev;
   2027 	dc->dc_func = func;
   2028 	TAILQ_INSERT_TAIL(&mountroot_config_queue, dc, dc_queue);
   2029 }
   2030 
   2031 /*
   2032  * Process a deferred configuration queue.
   2033  */
   2034 static void
   2035 config_process_deferred(struct deferred_config_head *queue, device_t parent)
   2036 {
   2037 	struct deferred_config *dc, *ndc;
   2038 
   2039 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
   2040 		ndc = TAILQ_NEXT(dc, dc_queue);
   2041 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
   2042 			TAILQ_REMOVE(queue, dc, dc_queue);
   2043 			(*dc->dc_func)(dc->dc_dev);
   2044 			config_pending_decr(dc->dc_dev);
   2045 			kmem_free(dc, sizeof(*dc));
   2046 		}
   2047 	}
   2048 }
   2049 
   2050 /*
   2051  * Manipulate the config_pending semaphore.
   2052  */
   2053 void
   2054 config_pending_incr(device_t dev)
   2055 {
   2056 
   2057 	mutex_enter(&config_misc_lock);
   2058 	config_pending++;
   2059 #ifdef DEBUG_AUTOCONF
   2060 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
   2061 #endif
   2062 	mutex_exit(&config_misc_lock);
   2063 }
   2064 
   2065 void
   2066 config_pending_decr(device_t dev)
   2067 {
   2068 
   2069 	KASSERT(0 < config_pending);
   2070 	mutex_enter(&config_misc_lock);
   2071 	config_pending--;
   2072 #ifdef DEBUG_AUTOCONF
   2073 	printf("%s: %s %d\n", __func__, device_xname(dev), config_pending);
   2074 #endif
   2075 	if (config_pending == 0)
   2076 		cv_broadcast(&config_misc_cv);
   2077 	mutex_exit(&config_misc_lock);
   2078 }
   2079 
   2080 /*
   2081  * Register a "finalization" routine.  Finalization routines are
   2082  * called iteratively once all real devices have been found during
   2083  * autoconfiguration, for as long as any one finalizer has done
   2084  * any work.
   2085  */
   2086 int
   2087 config_finalize_register(device_t dev, int (*fn)(device_t))
   2088 {
   2089 	struct finalize_hook *f;
   2090 
   2091 	/*
   2092 	 * If finalization has already been done, invoke the
   2093 	 * callback function now.
   2094 	 */
   2095 	if (config_finalize_done) {
   2096 		while ((*fn)(dev) != 0)
   2097 			/* loop */ ;
   2098 		return 0;
   2099 	}
   2100 
   2101 	/* Ensure this isn't already on the list. */
   2102 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
   2103 		if (f->f_func == fn && f->f_dev == dev)
   2104 			return EEXIST;
   2105 	}
   2106 
   2107 	f = kmem_alloc(sizeof(*f), KM_SLEEP);
   2108 	f->f_func = fn;
   2109 	f->f_dev = dev;
   2110 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
   2111 
   2112 	return 0;
   2113 }
   2114 
   2115 void
   2116 config_finalize(void)
   2117 {
   2118 	struct finalize_hook *f;
   2119 	struct pdevinit *pdev;
   2120 	extern struct pdevinit pdevinit[];
   2121 	int errcnt, rv;
   2122 
   2123 	/*
   2124 	 * Now that device driver threads have been created, wait for
   2125 	 * them to finish any deferred autoconfiguration.
   2126 	 */
   2127 	mutex_enter(&config_misc_lock);
   2128 	while (config_pending != 0)
   2129 		cv_wait(&config_misc_cv, &config_misc_lock);
   2130 	mutex_exit(&config_misc_lock);
   2131 
   2132 	KERNEL_LOCK(1, NULL);
   2133 
   2134 	/* Attach pseudo-devices. */
   2135 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
   2136 		(*pdev->pdev_attach)(pdev->pdev_count);
   2137 
   2138 	/* Run the hooks until none of them does any work. */
   2139 	do {
   2140 		rv = 0;
   2141 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
   2142 			rv |= (*f->f_func)(f->f_dev);
   2143 	} while (rv != 0);
   2144 
   2145 	config_finalize_done = 1;
   2146 
   2147 	/* Now free all the hooks. */
   2148 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
   2149 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
   2150 		kmem_free(f, sizeof(*f));
   2151 	}
   2152 
   2153 	KERNEL_UNLOCK_ONE(NULL);
   2154 
   2155 	errcnt = aprint_get_error_count();
   2156 	if ((boothowto & (AB_QUIET|AB_SILENT)) != 0 &&
   2157 	    (boothowto & AB_VERBOSE) == 0) {
   2158 		mutex_enter(&config_misc_lock);
   2159 		if (config_do_twiddle) {
   2160 			config_do_twiddle = 0;
   2161 			printf_nolog(" done.\n");
   2162 		}
   2163 		mutex_exit(&config_misc_lock);
   2164 	}
   2165 	if (errcnt != 0) {
   2166 		printf("WARNING: %d error%s while detecting hardware; "
   2167 		    "check system log.\n", errcnt,
   2168 		    errcnt == 1 ? "" : "s");
   2169 	}
   2170 }
   2171 
   2172 void
   2173 config_twiddle_init(void)
   2174 {
   2175 
   2176 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
   2177 		config_do_twiddle = 1;
   2178 	}
   2179 	callout_setfunc(&config_twiddle_ch, config_twiddle_fn, NULL);
   2180 }
   2181 
   2182 void
   2183 config_twiddle_fn(void *cookie)
   2184 {
   2185 
   2186 	mutex_enter(&config_misc_lock);
   2187 	if (config_do_twiddle) {
   2188 		twiddle();
   2189 		callout_schedule(&config_twiddle_ch, mstohz(100));
   2190 	}
   2191 	mutex_exit(&config_misc_lock);
   2192 }
   2193 
   2194 static void
   2195 config_alldevs_enter(struct alldevs_foray *af)
   2196 {
   2197 	TAILQ_INIT(&af->af_garbage);
   2198 	mutex_enter(&alldevs_lock);
   2199 	config_collect_garbage(&af->af_garbage);
   2200 }
   2201 
   2202 static void
   2203 config_alldevs_exit(struct alldevs_foray *af)
   2204 {
   2205 	mutex_exit(&alldevs_lock);
   2206 	config_dump_garbage(&af->af_garbage);
   2207 }
   2208 
   2209 /*
   2210  * device_lookup:
   2211  *
   2212  *	Look up a device instance for a given driver.
   2213  */
   2214 device_t
   2215 device_lookup(cfdriver_t cd, int unit)
   2216 {
   2217 	device_t dv;
   2218 
   2219 	mutex_enter(&alldevs_lock);
   2220 	if (unit < 0 || unit >= cd->cd_ndevs)
   2221 		dv = NULL;
   2222 	else if ((dv = cd->cd_devs[unit]) != NULL && dv->dv_del_gen != 0)
   2223 		dv = NULL;
   2224 	mutex_exit(&alldevs_lock);
   2225 
   2226 	return dv;
   2227 }
   2228 
   2229 /*
   2230  * device_lookup_private:
   2231  *
   2232  *	Look up a softc instance for a given driver.
   2233  */
   2234 void *
   2235 device_lookup_private(cfdriver_t cd, int unit)
   2236 {
   2237 
   2238 	return device_private(device_lookup(cd, unit));
   2239 }
   2240 
   2241 /*
   2242  * device_find_by_xname:
   2243  *
   2244  *	Returns the device of the given name or NULL if it doesn't exist.
   2245  */
   2246 device_t
   2247 device_find_by_xname(const char *name)
   2248 {
   2249 	device_t dv;
   2250 	deviter_t di;
   2251 
   2252 	for (dv = deviter_first(&di, 0); dv != NULL; dv = deviter_next(&di)) {
   2253 		if (strcmp(device_xname(dv), name) == 0)
   2254 			break;
   2255 	}
   2256 	deviter_release(&di);
   2257 
   2258 	return dv;
   2259 }
   2260 
   2261 /*
   2262  * device_find_by_driver_unit:
   2263  *
   2264  *	Returns the device of the given driver name and unit or
   2265  *	NULL if it doesn't exist.
   2266  */
   2267 device_t
   2268 device_find_by_driver_unit(const char *name, int unit)
   2269 {
   2270 	struct cfdriver *cd;
   2271 
   2272 	if ((cd = config_cfdriver_lookup(name)) == NULL)
   2273 		return NULL;
   2274 	return device_lookup(cd, unit);
   2275 }
   2276 
   2277 /*
   2278  * device_compatible_match:
   2279  *
   2280  *	Match a driver's "compatible" data against a device's
   2281  *	"compatible" strings.  If a match is found, we return
   2282  *	a weighted match result, and optionally the matching
   2283  *	entry.
   2284  */
   2285 int
   2286 device_compatible_match(const char **device_compats, int ndevice_compats,
   2287 			const struct device_compatible_entry *driver_compats,
   2288 			const struct device_compatible_entry **matching_entryp)
   2289 {
   2290 	const struct device_compatible_entry *dce = NULL;
   2291 	int i, match_weight;
   2292 
   2293 	if (ndevice_compats == 0 || device_compats == NULL ||
   2294 	    driver_compats == NULL)
   2295 		return 0;
   2296 
   2297 	/*
   2298 	 * We take the first match because we start with the most-specific
   2299 	 * device compatible string.
   2300 	 */
   2301 	for (i = 0, match_weight = ndevice_compats - 1;
   2302 	     i < ndevice_compats;
   2303 	     i++, match_weight--) {
   2304 		for (dce = driver_compats; dce->compat != NULL; dce++) {
   2305 			if (strcmp(dce->compat, device_compats[i]) == 0) {
   2306 				KASSERT(match_weight >= 0);
   2307 				if (matching_entryp)
   2308 					*matching_entryp = dce;
   2309 				return 1 + match_weight;
   2310 			}
   2311 		}
   2312 	}
   2313 	return 0;
   2314 }
   2315 
   2316 /*
   2317  * Power management related functions.
   2318  */
   2319 
   2320 bool
   2321 device_pmf_is_registered(device_t dev)
   2322 {
   2323 	return (dev->dv_flags & DVF_POWER_HANDLERS) != 0;
   2324 }
   2325 
   2326 bool
   2327 device_pmf_driver_suspend(device_t dev, const pmf_qual_t *qual)
   2328 {
   2329 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
   2330 		return true;
   2331 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
   2332 		return false;
   2333 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
   2334 	    dev->dv_driver_suspend != NULL &&
   2335 	    !(*dev->dv_driver_suspend)(dev, qual))
   2336 		return false;
   2337 
   2338 	dev->dv_flags |= DVF_DRIVER_SUSPENDED;
   2339 	return true;
   2340 }
   2341 
   2342 bool
   2343 device_pmf_driver_resume(device_t dev, const pmf_qual_t *qual)
   2344 {
   2345 	if ((dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
   2346 		return true;
   2347 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
   2348 		return false;
   2349 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_DRIVER &&
   2350 	    dev->dv_driver_resume != NULL &&
   2351 	    !(*dev->dv_driver_resume)(dev, qual))
   2352 		return false;
   2353 
   2354 	dev->dv_flags &= ~DVF_DRIVER_SUSPENDED;
   2355 	return true;
   2356 }
   2357 
   2358 bool
   2359 device_pmf_driver_shutdown(device_t dev, int how)
   2360 {
   2361 
   2362 	if (*dev->dv_driver_shutdown != NULL &&
   2363 	    !(*dev->dv_driver_shutdown)(dev, how))
   2364 		return false;
   2365 	return true;
   2366 }
   2367 
   2368 bool
   2369 device_pmf_driver_register(device_t dev,
   2370     bool (*suspend)(device_t, const pmf_qual_t *),
   2371     bool (*resume)(device_t, const pmf_qual_t *),
   2372     bool (*shutdown)(device_t, int))
   2373 {
   2374 	dev->dv_driver_suspend = suspend;
   2375 	dev->dv_driver_resume = resume;
   2376 	dev->dv_driver_shutdown = shutdown;
   2377 	dev->dv_flags |= DVF_POWER_HANDLERS;
   2378 	return true;
   2379 }
   2380 
   2381 static const char *
   2382 curlwp_name(void)
   2383 {
   2384 	if (curlwp->l_name != NULL)
   2385 		return curlwp->l_name;
   2386 	else
   2387 		return curlwp->l_proc->p_comm;
   2388 }
   2389 
   2390 void
   2391 device_pmf_driver_deregister(device_t dev)
   2392 {
   2393 	device_lock_t dvl = device_getlock(dev);
   2394 
   2395 	dev->dv_driver_suspend = NULL;
   2396 	dev->dv_driver_resume = NULL;
   2397 
   2398 	mutex_enter(&dvl->dvl_mtx);
   2399 	dev->dv_flags &= ~DVF_POWER_HANDLERS;
   2400 	while (dvl->dvl_nlock > 0 || dvl->dvl_nwait > 0) {
   2401 		/* Wake a thread that waits for the lock.  That
   2402 		 * thread will fail to acquire the lock, and then
   2403 		 * it will wake the next thread that waits for the
   2404 		 * lock, or else it will wake us.
   2405 		 */
   2406 		cv_signal(&dvl->dvl_cv);
   2407 		pmflock_debug(dev, __func__, __LINE__);
   2408 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
   2409 		pmflock_debug(dev, __func__, __LINE__);
   2410 	}
   2411 	mutex_exit(&dvl->dvl_mtx);
   2412 }
   2413 
   2414 bool
   2415 device_pmf_driver_child_register(device_t dev)
   2416 {
   2417 	device_t parent = device_parent(dev);
   2418 
   2419 	if (parent == NULL || parent->dv_driver_child_register == NULL)
   2420 		return true;
   2421 	return (*parent->dv_driver_child_register)(dev);
   2422 }
   2423 
   2424 void
   2425 device_pmf_driver_set_child_register(device_t dev,
   2426     bool (*child_register)(device_t))
   2427 {
   2428 	dev->dv_driver_child_register = child_register;
   2429 }
   2430 
   2431 static void
   2432 pmflock_debug(device_t dev, const char *func, int line)
   2433 {
   2434 	device_lock_t dvl = device_getlock(dev);
   2435 
   2436 	aprint_debug_dev(dev,
   2437 	    "%s.%d, %s dvl_nlock %d dvl_nwait %d dv_flags %x\n", func, line,
   2438 	    curlwp_name(), dvl->dvl_nlock, dvl->dvl_nwait, dev->dv_flags);
   2439 }
   2440 
   2441 static bool
   2442 device_pmf_lock1(device_t dev)
   2443 {
   2444 	device_lock_t dvl = device_getlock(dev);
   2445 
   2446 	while (device_pmf_is_registered(dev) &&
   2447 	    dvl->dvl_nlock > 0 && dvl->dvl_holder != curlwp) {
   2448 		dvl->dvl_nwait++;
   2449 		pmflock_debug(dev, __func__, __LINE__);
   2450 		cv_wait(&dvl->dvl_cv, &dvl->dvl_mtx);
   2451 		pmflock_debug(dev, __func__, __LINE__);
   2452 		dvl->dvl_nwait--;
   2453 	}
   2454 	if (!device_pmf_is_registered(dev)) {
   2455 		pmflock_debug(dev, __func__, __LINE__);
   2456 		/* We could not acquire the lock, but some other thread may
   2457 		 * wait for it, also.  Wake that thread.
   2458 		 */
   2459 		cv_signal(&dvl->dvl_cv);
   2460 		return false;
   2461 	}
   2462 	dvl->dvl_nlock++;
   2463 	dvl->dvl_holder = curlwp;
   2464 	pmflock_debug(dev, __func__, __LINE__);
   2465 	return true;
   2466 }
   2467 
   2468 bool
   2469 device_pmf_lock(device_t dev)
   2470 {
   2471 	bool rc;
   2472 	device_lock_t dvl = device_getlock(dev);
   2473 
   2474 	mutex_enter(&dvl->dvl_mtx);
   2475 	rc = device_pmf_lock1(dev);
   2476 	mutex_exit(&dvl->dvl_mtx);
   2477 
   2478 	return rc;
   2479 }
   2480 
   2481 void
   2482 device_pmf_unlock(device_t dev)
   2483 {
   2484 	device_lock_t dvl = device_getlock(dev);
   2485 
   2486 	KASSERT(dvl->dvl_nlock > 0);
   2487 	mutex_enter(&dvl->dvl_mtx);
   2488 	if (--dvl->dvl_nlock == 0)
   2489 		dvl->dvl_holder = NULL;
   2490 	cv_signal(&dvl->dvl_cv);
   2491 	pmflock_debug(dev, __func__, __LINE__);
   2492 	mutex_exit(&dvl->dvl_mtx);
   2493 }
   2494 
   2495 device_lock_t
   2496 device_getlock(device_t dev)
   2497 {
   2498 	return &dev->dv_lock;
   2499 }
   2500 
   2501 void *
   2502 device_pmf_bus_private(device_t dev)
   2503 {
   2504 	return dev->dv_bus_private;
   2505 }
   2506 
   2507 bool
   2508 device_pmf_bus_suspend(device_t dev, const pmf_qual_t *qual)
   2509 {
   2510 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0)
   2511 		return true;
   2512 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0 ||
   2513 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) == 0)
   2514 		return false;
   2515 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
   2516 	    dev->dv_bus_suspend != NULL &&
   2517 	    !(*dev->dv_bus_suspend)(dev, qual))
   2518 		return false;
   2519 
   2520 	dev->dv_flags |= DVF_BUS_SUSPENDED;
   2521 	return true;
   2522 }
   2523 
   2524 bool
   2525 device_pmf_bus_resume(device_t dev, const pmf_qual_t *qual)
   2526 {
   2527 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) == 0)
   2528 		return true;
   2529 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_BUS &&
   2530 	    dev->dv_bus_resume != NULL &&
   2531 	    !(*dev->dv_bus_resume)(dev, qual))
   2532 		return false;
   2533 
   2534 	dev->dv_flags &= ~DVF_BUS_SUSPENDED;
   2535 	return true;
   2536 }
   2537 
   2538 bool
   2539 device_pmf_bus_shutdown(device_t dev, int how)
   2540 {
   2541 
   2542 	if (*dev->dv_bus_shutdown != NULL &&
   2543 	    !(*dev->dv_bus_shutdown)(dev, how))
   2544 		return false;
   2545 	return true;
   2546 }
   2547 
   2548 void
   2549 device_pmf_bus_register(device_t dev, void *priv,
   2550     bool (*suspend)(device_t, const pmf_qual_t *),
   2551     bool (*resume)(device_t, const pmf_qual_t *),
   2552     bool (*shutdown)(device_t, int), void (*deregister)(device_t))
   2553 {
   2554 	dev->dv_bus_private = priv;
   2555 	dev->dv_bus_resume = resume;
   2556 	dev->dv_bus_suspend = suspend;
   2557 	dev->dv_bus_shutdown = shutdown;
   2558 	dev->dv_bus_deregister = deregister;
   2559 }
   2560 
   2561 void
   2562 device_pmf_bus_deregister(device_t dev)
   2563 {
   2564 	if (dev->dv_bus_deregister == NULL)
   2565 		return;
   2566 	(*dev->dv_bus_deregister)(dev);
   2567 	dev->dv_bus_private = NULL;
   2568 	dev->dv_bus_suspend = NULL;
   2569 	dev->dv_bus_resume = NULL;
   2570 	dev->dv_bus_deregister = NULL;
   2571 }
   2572 
   2573 void *
   2574 device_pmf_class_private(device_t dev)
   2575 {
   2576 	return dev->dv_class_private;
   2577 }
   2578 
   2579 bool
   2580 device_pmf_class_suspend(device_t dev, const pmf_qual_t *qual)
   2581 {
   2582 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) != 0)
   2583 		return true;
   2584 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
   2585 	    dev->dv_class_suspend != NULL &&
   2586 	    !(*dev->dv_class_suspend)(dev, qual))
   2587 		return false;
   2588 
   2589 	dev->dv_flags |= DVF_CLASS_SUSPENDED;
   2590 	return true;
   2591 }
   2592 
   2593 bool
   2594 device_pmf_class_resume(device_t dev, const pmf_qual_t *qual)
   2595 {
   2596 	if ((dev->dv_flags & DVF_CLASS_SUSPENDED) == 0)
   2597 		return true;
   2598 	if ((dev->dv_flags & DVF_BUS_SUSPENDED) != 0 ||
   2599 	    (dev->dv_flags & DVF_DRIVER_SUSPENDED) != 0)
   2600 		return false;
   2601 	if (pmf_qual_depth(qual) <= DEVACT_LEVEL_CLASS &&
   2602 	    dev->dv_class_resume != NULL &&
   2603 	    !(*dev->dv_class_resume)(dev, qual))
   2604 		return false;
   2605 
   2606 	dev->dv_flags &= ~DVF_CLASS_SUSPENDED;
   2607 	return true;
   2608 }
   2609 
   2610 void
   2611 device_pmf_class_register(device_t dev, void *priv,
   2612     bool (*suspend)(device_t, const pmf_qual_t *),
   2613     bool (*resume)(device_t, const pmf_qual_t *),
   2614     void (*deregister)(device_t))
   2615 {
   2616 	dev->dv_class_private = priv;
   2617 	dev->dv_class_suspend = suspend;
   2618 	dev->dv_class_resume = resume;
   2619 	dev->dv_class_deregister = deregister;
   2620 }
   2621 
   2622 void
   2623 device_pmf_class_deregister(device_t dev)
   2624 {
   2625 	if (dev->dv_class_deregister == NULL)
   2626 		return;
   2627 	(*dev->dv_class_deregister)(dev);
   2628 	dev->dv_class_private = NULL;
   2629 	dev->dv_class_suspend = NULL;
   2630 	dev->dv_class_resume = NULL;
   2631 	dev->dv_class_deregister = NULL;
   2632 }
   2633 
   2634 bool
   2635 device_active(device_t dev, devactive_t type)
   2636 {
   2637 	size_t i;
   2638 
   2639 	if (dev->dv_activity_count == 0)
   2640 		return false;
   2641 
   2642 	for (i = 0; i < dev->dv_activity_count; ++i) {
   2643 		if (dev->dv_activity_handlers[i] == NULL)
   2644 			break;
   2645 		(*dev->dv_activity_handlers[i])(dev, type);
   2646 	}
   2647 
   2648 	return true;
   2649 }
   2650 
   2651 bool
   2652 device_active_register(device_t dev, void (*handler)(device_t, devactive_t))
   2653 {
   2654 	void (**new_handlers)(device_t, devactive_t);
   2655 	void (**old_handlers)(device_t, devactive_t);
   2656 	size_t i, old_size, new_size;
   2657 	int s;
   2658 
   2659 	old_handlers = dev->dv_activity_handlers;
   2660 	old_size = dev->dv_activity_count;
   2661 
   2662 	KASSERT(old_size == 0 || old_handlers != NULL);
   2663 
   2664 	for (i = 0; i < old_size; ++i) {
   2665 		KASSERT(old_handlers[i] != handler);
   2666 		if (old_handlers[i] == NULL) {
   2667 			old_handlers[i] = handler;
   2668 			return true;
   2669 		}
   2670 	}
   2671 
   2672 	new_size = old_size + 4;
   2673 	new_handlers = kmem_alloc(sizeof(void *[new_size]), KM_SLEEP);
   2674 
   2675 	for (i = 0; i < old_size; ++i)
   2676 		new_handlers[i] = old_handlers[i];
   2677 	new_handlers[old_size] = handler;
   2678 	for (i = old_size+1; i < new_size; ++i)
   2679 		new_handlers[i] = NULL;
   2680 
   2681 	s = splhigh();
   2682 	dev->dv_activity_count = new_size;
   2683 	dev->dv_activity_handlers = new_handlers;
   2684 	splx(s);
   2685 
   2686 	if (old_size > 0)
   2687 		kmem_free(old_handlers, sizeof(void * [old_size]));
   2688 
   2689 	return true;
   2690 }
   2691 
   2692 void
   2693 device_active_deregister(device_t dev, void (*handler)(device_t, devactive_t))
   2694 {
   2695 	void (**old_handlers)(device_t, devactive_t);
   2696 	size_t i, old_size;
   2697 	int s;
   2698 
   2699 	old_handlers = dev->dv_activity_handlers;
   2700 	old_size = dev->dv_activity_count;
   2701 
   2702 	for (i = 0; i < old_size; ++i) {
   2703 		if (old_handlers[i] == handler)
   2704 			break;
   2705 		if (old_handlers[i] == NULL)
   2706 			return; /* XXX panic? */
   2707 	}
   2708 
   2709 	if (i == old_size)
   2710 		return; /* XXX panic? */
   2711 
   2712 	for (; i < old_size - 1; ++i) {
   2713 		if ((old_handlers[i] = old_handlers[i + 1]) != NULL)
   2714 			continue;
   2715 
   2716 		if (i == 0) {
   2717 			s = splhigh();
   2718 			dev->dv_activity_count = 0;
   2719 			dev->dv_activity_handlers = NULL;
   2720 			splx(s);
   2721 			kmem_free(old_handlers, sizeof(void *[old_size]));
   2722 		}
   2723 		return;
   2724 	}
   2725 	old_handlers[i] = NULL;
   2726 }
   2727 
   2728 /* Return true iff the device_t `dev' exists at generation `gen'. */
   2729 static bool
   2730 device_exists_at(device_t dv, devgen_t gen)
   2731 {
   2732 	return (dv->dv_del_gen == 0 || dv->dv_del_gen > gen) &&
   2733 	    dv->dv_add_gen <= gen;
   2734 }
   2735 
   2736 static bool
   2737 deviter_visits(const deviter_t *di, device_t dv)
   2738 {
   2739 	return device_exists_at(dv, di->di_gen);
   2740 }
   2741 
   2742 /*
   2743  * Device Iteration
   2744  *
   2745  * deviter_t: a device iterator.  Holds state for a "walk" visiting
   2746  *     each device_t's in the device tree.
   2747  *
   2748  * deviter_init(di, flags): initialize the device iterator `di'
   2749  *     to "walk" the device tree.  deviter_next(di) will return
   2750  *     the first device_t in the device tree, or NULL if there are
   2751  *     no devices.
   2752  *
   2753  *     `flags' is one or more of DEVITER_F_RW, indicating that the
   2754  *     caller intends to modify the device tree by calling
   2755  *     config_detach(9) on devices in the order that the iterator
   2756  *     returns them; DEVITER_F_ROOT_FIRST, asking for the devices
   2757  *     nearest the "root" of the device tree to be returned, first;
   2758  *     DEVITER_F_LEAVES_FIRST, asking for the devices furthest from
   2759  *     the root of the device tree, first; and DEVITER_F_SHUTDOWN,
   2760  *     indicating both that deviter_init() should not respect any
   2761  *     locks on the device tree, and that deviter_next(di) may run
   2762  *     in more than one LWP before the walk has finished.
   2763  *
   2764  *     Only one DEVITER_F_RW iterator may be in the device tree at
   2765  *     once.
   2766  *
   2767  *     DEVITER_F_SHUTDOWN implies DEVITER_F_RW.
   2768  *
   2769  *     Results are undefined if the flags DEVITER_F_ROOT_FIRST and
   2770  *     DEVITER_F_LEAVES_FIRST are used in combination.
   2771  *
   2772  * deviter_first(di, flags): initialize the device iterator `di'
   2773  *     and return the first device_t in the device tree, or NULL
   2774  *     if there are no devices.  The statement
   2775  *
   2776  *         dv = deviter_first(di);
   2777  *
   2778  *     is shorthand for
   2779  *
   2780  *         deviter_init(di);
   2781  *         dv = deviter_next(di);
   2782  *
   2783  * deviter_next(di): return the next device_t in the device tree,
   2784  *     or NULL if there are no more devices.  deviter_next(di)
   2785  *     is undefined if `di' was not initialized with deviter_init() or
   2786  *     deviter_first().
   2787  *
   2788  * deviter_release(di): stops iteration (subsequent calls to
   2789  *     deviter_next() will return NULL), releases any locks and
   2790  *     resources held by the device iterator.
   2791  *
   2792  * Device iteration does not return device_t's in any particular
   2793  * order.  An iterator will never return the same device_t twice.
   2794  * Device iteration is guaranteed to complete---i.e., if deviter_next(di)
   2795  * is called repeatedly on the same `di', it will eventually return
   2796  * NULL.  It is ok to attach/detach devices during device iteration.
   2797  */
   2798 void
   2799 deviter_init(deviter_t *di, deviter_flags_t flags)
   2800 {
   2801 	device_t dv;
   2802 
   2803 	memset(di, 0, sizeof(*di));
   2804 
   2805 	if ((flags & DEVITER_F_SHUTDOWN) != 0)
   2806 		flags |= DEVITER_F_RW;
   2807 
   2808 	mutex_enter(&alldevs_lock);
   2809 	if ((flags & DEVITER_F_RW) != 0)
   2810 		alldevs_nwrite++;
   2811 	else
   2812 		alldevs_nread++;
   2813 	di->di_gen = alldevs_gen++;
   2814 	di->di_flags = flags;
   2815 
   2816 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
   2817 	case DEVITER_F_LEAVES_FIRST:
   2818 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   2819 			if (!deviter_visits(di, dv))
   2820 				continue;
   2821 			di->di_curdepth = MAX(di->di_curdepth, dv->dv_depth);
   2822 		}
   2823 		break;
   2824 	case DEVITER_F_ROOT_FIRST:
   2825 		TAILQ_FOREACH(dv, &alldevs, dv_list) {
   2826 			if (!deviter_visits(di, dv))
   2827 				continue;
   2828 			di->di_maxdepth = MAX(di->di_maxdepth, dv->dv_depth);
   2829 		}
   2830 		break;
   2831 	default:
   2832 		break;
   2833 	}
   2834 
   2835 	deviter_reinit(di);
   2836 	mutex_exit(&alldevs_lock);
   2837 }
   2838 
   2839 static void
   2840 deviter_reinit(deviter_t *di)
   2841 {
   2842 
   2843 	KASSERT(mutex_owned(&alldevs_lock));
   2844 	if ((di->di_flags & DEVITER_F_RW) != 0)
   2845 		di->di_prev = TAILQ_LAST(&alldevs, devicelist);
   2846 	else
   2847 		di->di_prev = TAILQ_FIRST(&alldevs);
   2848 }
   2849 
   2850 device_t
   2851 deviter_first(deviter_t *di, deviter_flags_t flags)
   2852 {
   2853 
   2854 	deviter_init(di, flags);
   2855 	return deviter_next(di);
   2856 }
   2857 
   2858 static device_t
   2859 deviter_next2(deviter_t *di)
   2860 {
   2861 	device_t dv;
   2862 
   2863 	KASSERT(mutex_owned(&alldevs_lock));
   2864 
   2865 	dv = di->di_prev;
   2866 
   2867 	if (dv == NULL)
   2868 		return NULL;
   2869 
   2870 	if ((di->di_flags & DEVITER_F_RW) != 0)
   2871 		di->di_prev = TAILQ_PREV(dv, devicelist, dv_list);
   2872 	else
   2873 		di->di_prev = TAILQ_NEXT(dv, dv_list);
   2874 
   2875 	return dv;
   2876 }
   2877 
   2878 static device_t
   2879 deviter_next1(deviter_t *di)
   2880 {
   2881 	device_t dv;
   2882 
   2883 	KASSERT(mutex_owned(&alldevs_lock));
   2884 
   2885 	do {
   2886 		dv = deviter_next2(di);
   2887 	} while (dv != NULL && !deviter_visits(di, dv));
   2888 
   2889 	return dv;
   2890 }
   2891 
   2892 device_t
   2893 deviter_next(deviter_t *di)
   2894 {
   2895 	device_t dv = NULL;
   2896 
   2897 	mutex_enter(&alldevs_lock);
   2898 	switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
   2899 	case 0:
   2900 		dv = deviter_next1(di);
   2901 		break;
   2902 	case DEVITER_F_LEAVES_FIRST:
   2903 		while (di->di_curdepth >= 0) {
   2904 			if ((dv = deviter_next1(di)) == NULL) {
   2905 				di->di_curdepth--;
   2906 				deviter_reinit(di);
   2907 			} else if (dv->dv_depth == di->di_curdepth)
   2908 				break;
   2909 		}
   2910 		break;
   2911 	case DEVITER_F_ROOT_FIRST:
   2912 		while (di->di_curdepth <= di->di_maxdepth) {
   2913 			if ((dv = deviter_next1(di)) == NULL) {
   2914 				di->di_curdepth++;
   2915 				deviter_reinit(di);
   2916 			} else if (dv->dv_depth == di->di_curdepth)
   2917 				break;
   2918 		}
   2919 		break;
   2920 	default:
   2921 		break;
   2922 	}
   2923 	mutex_exit(&alldevs_lock);
   2924 
   2925 	return dv;
   2926 }
   2927 
   2928 void
   2929 deviter_release(deviter_t *di)
   2930 {
   2931 	bool rw = (di->di_flags & DEVITER_F_RW) != 0;
   2932 
   2933 	mutex_enter(&alldevs_lock);
   2934 	if (rw)
   2935 		--alldevs_nwrite;
   2936 	else
   2937 		--alldevs_nread;
   2938 	/* XXX wake a garbage-collection thread */
   2939 	mutex_exit(&alldevs_lock);
   2940 }
   2941 
   2942 const char *
   2943 cfdata_ifattr(const struct cfdata *cf)
   2944 {
   2945 	return cf->cf_pspec->cfp_iattr;
   2946 }
   2947 
   2948 bool
   2949 ifattr_match(const char *snull, const char *t)
   2950 {
   2951 	return (snull == NULL) || strcmp(snull, t) == 0;
   2952 }
   2953 
   2954 void
   2955 null_childdetached(device_t self, device_t child)
   2956 {
   2957 	/* do nothing */
   2958 }
   2959 
   2960 static void
   2961 sysctl_detach_setup(struct sysctllog **clog)
   2962 {
   2963 
   2964 	sysctl_createv(clog, 0, NULL, NULL,
   2965 		CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
   2966 		CTLTYPE_BOOL, "detachall",
   2967 		SYSCTL_DESCR("Detach all devices at shutdown"),
   2968 		NULL, 0, &detachall, 0,
   2969 		CTL_KERN, CTL_CREATE, CTL_EOL);
   2970 }
   2971