xref: /dragonfly/sys/kern/kern_udev.c (revision a563ca70)
1 /*
2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Alex Hornung <ahornung@gmail.com>
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  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/proc.h>
38 #include <sys/buf.h>
39 #include <sys/conf.h>
40 #include <sys/event.h>
41 #include <sys/ioccom.h>
42 #include <sys/malloc.h>
43 #include <sys/ctype.h>
44 #include <sys/syslog.h>
45 #include <sys/udev.h>
46 #include <sys/devfs.h>
47 #include <libprop/proplib.h>
48 
49 #include <sys/thread2.h>
50 
51 MALLOC_DEFINE(M_UDEV, "udev", "udev allocs");
52 
53 /* XXX: use UUIDs for identification; would need help from devfs */
54 
55 static cdev_t		udev_dev;
56 static d_open_t		udev_dev_open;
57 static d_close_t	udev_dev_close;
58 static d_read_t		udev_dev_read;
59 static d_kqfilter_t	udev_dev_kqfilter;
60 static d_ioctl_t	udev_dev_ioctl;
61 
62 static int _udev_dict_set_cstr(prop_dictionary_t, const char *, char *);
63 static int _udev_dict_set_int(prop_dictionary_t, const char *, int64_t);
64 static int _udev_dict_set_uint(prop_dictionary_t, const char *, uint64_t);
65 static int _udev_dict_delete_key(prop_dictionary_t, const char *);
66 static prop_dictionary_t udev_init_dict_event(cdev_t, const char *);
67 static int udev_init_dict(cdev_t);
68 static int udev_destroy_dict(cdev_t);
69 static void udev_event_insert(int, prop_dictionary_t);
70 static struct udev_event_kernel *udev_event_remove(void);
71 static void udev_event_free(struct udev_event_kernel *);
72 static char *udev_event_externalize(struct udev_event_kernel *);
73 static void udev_getdevs_scan_callback(cdev_t, void *);
74 static int udev_getdevs_ioctl(struct plistref *, u_long, prop_dictionary_t);
75 static void udev_dev_filter_detach(struct knote *);
76 static int udev_dev_filter_read(struct knote *, long);
77 
78 struct cmd_function {
79 	const char *cmd;
80 	int  (*fn)(struct plistref *, u_long, prop_dictionary_t);
81 };
82 
83 struct udev_prop_ctx {
84 	prop_array_t cdevs;
85 	int error;
86 };
87 
88 struct udev_event_kernel {
89 	struct udev_event ev;
90 	TAILQ_ENTRY(udev_event_kernel)	link;
91 };
92 
93 struct udev_softc {
94 	int opened;
95 	int initiated;
96 
97 	struct kqinfo kq;
98 
99 	int qlen;
100 	struct lock lock;
101 	TAILQ_HEAD(, udev_event_kernel) ev_queue;	/* list of thread_io */
102 } udevctx;
103 
104 static struct dev_ops udev_dev_ops = {
105 	{ "udev", 0, 0 },
106 	.d_open = udev_dev_open,
107 	.d_close = udev_dev_close,
108 	.d_read = udev_dev_read,
109 	.d_kqfilter = udev_dev_kqfilter,
110 	.d_ioctl = udev_dev_ioctl
111 };
112 
113 static struct cmd_function cmd_fn[] = {
114 		{ .cmd = "getdevs", .fn = udev_getdevs_ioctl},
115 		{NULL, NULL}
116 };
117 
118 static int
119 _udev_dict_set_cstr(prop_dictionary_t dict, const char *key, char *str)
120 {
121 	prop_string_t	ps;
122 
123 	KKASSERT(dict != NULL);
124 
125 	ps = prop_string_create_cstring(str);
126 	if (ps == NULL) {
127 		return ENOMEM;
128 	}
129 
130 	if (prop_dictionary_set(dict, key, ps) == false) {
131 		prop_object_release(ps);
132 		return ENOMEM;
133 	}
134 
135 	prop_object_release(ps);
136 	return 0;
137 }
138 
139 static int
140 _udev_dict_set_int(prop_dictionary_t dict, const char *key, int64_t val)
141 {
142 	prop_number_t	pn;
143 
144 	KKASSERT(dict != NULL);
145 
146 	pn = prop_number_create_integer(val);
147 	if (pn == NULL)
148 		return ENOMEM;
149 
150 	if (prop_dictionary_set(dict, key, pn) == false) {
151 		prop_object_release(pn);
152 		return ENOMEM;
153 	}
154 
155 	prop_object_release(pn);
156 	return 0;
157 }
158 
159 static int
160 _udev_dict_set_uint(prop_dictionary_t dict, const char *key, uint64_t val)
161 {
162 	prop_number_t	pn;
163 
164 	KKASSERT(dict != NULL);
165 
166 	pn = prop_number_create_unsigned_integer(val);
167 	if (pn == NULL)
168 		return ENOMEM;
169 
170 	if (prop_dictionary_set(dict, key, pn) == false) {
171 		prop_object_release(pn);
172 		return ENOMEM;
173 	}
174 
175 	prop_object_release(pn);
176 	return 0;
177 }
178 
179 static int
180 _udev_dict_delete_key(prop_dictionary_t dict, const char *key)
181 {
182 	KKASSERT(dict != NULL);
183 
184 	prop_dictionary_remove(dict, key);
185 
186 	return 0;
187 }
188 
189 /*
190  * Initialize an event dictionary, which contains three parameters to
191  * identify the device referred to (name, devnum, kptr) and the affected key.
192  */
193 static prop_dictionary_t
194 udev_init_dict_event(cdev_t dev, const char *key)
195 {
196 	prop_dictionary_t	dict;
197 	uint64_t	kptr;
198 	int error;
199 
200 	kptr = (uint64_t)(uintptr_t)dev;
201 	KKASSERT(dev != NULL);
202 
203 	dict = prop_dictionary_create();
204 	if (dict == NULL) {
205 		log(LOG_DEBUG, "udev_init_dict_event: prop_dictionary_create() failed\n");
206 		return NULL;
207 	}
208 
209 	if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
210 		goto error_out;
211 	if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
212 		goto error_out;
213 	if ((error = _udev_dict_set_uint(dict, "devtype", (dev_dflags(dev) & D_TYPEMASK))))
214 		goto error_out;
215 	if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
216 		goto error_out;
217 	if ((error = _udev_dict_set_cstr(dict, "key", __DECONST(char *, key))))
218 		goto error_out;
219 
220 	return dict;
221 
222 error_out:
223 	prop_object_release(dict);
224 	return NULL;
225 }
226 
227 int
228 udev_dict_set_cstr(cdev_t dev, const char *key, char *str)
229 {
230 	prop_dictionary_t	dict;
231 	int error;
232 
233 	KKASSERT(dev != NULL);
234 
235 	if (dev->si_dict == NULL) {
236 		error = udev_init_dict(dev);
237 		if (error)
238 			return -1;
239 	}
240 
241 	/* Queue a key update event */
242 	dict = udev_init_dict_event(dev, key);
243 	if (dict == NULL)
244 		return ENOMEM;
245 
246 	if ((error = _udev_dict_set_cstr(dict, "value", str))) {
247 		prop_object_release(dict);
248 		return error;
249 	}
250 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
251 	prop_object_release(dict);
252 
253 	error = _udev_dict_set_cstr(dev->si_dict, key, str);
254 	return error;
255 }
256 
257 int
258 udev_dict_set_int(cdev_t dev, const char *key, int64_t val)
259 {
260 	prop_dictionary_t	dict;
261 	int error;
262 
263 	KKASSERT(dev != NULL);
264 
265 	if (dev->si_dict == NULL) {
266 		error = udev_init_dict(dev);
267 		if (error)
268 			return -1;
269 	}
270 
271 	/* Queue a key update event */
272 	dict = udev_init_dict_event(dev, key);
273 	if (dict == NULL)
274 		return ENOMEM;
275 	if ((error = _udev_dict_set_int(dict, "value", val))) {
276 		prop_object_release(dict);
277 		return error;
278 	}
279 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
280 	prop_object_release(dict);
281 
282 	return _udev_dict_set_int(dev->si_dict, key, val);
283 }
284 
285 int
286 udev_dict_set_uint(cdev_t dev, const char *key, uint64_t val)
287 {
288 	prop_dictionary_t	dict;
289 	int error;
290 
291 	KKASSERT(dev != NULL);
292 
293 	if (dev->si_dict == NULL) {
294 		error = udev_init_dict(dev);
295 		if (error)
296 			return -1;
297 	}
298 
299 	/* Queue a key update event */
300 	dict = udev_init_dict_event(dev, key);
301 	if (dict == NULL)
302 		return ENOMEM;
303 	if ((error = _udev_dict_set_uint(dict, "value", val))) {
304 		prop_object_release(dict);
305 		return error;
306 	}
307 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
308 	prop_object_release(dict);
309 
310 	return _udev_dict_set_uint(dev->si_dict, key, val);
311 }
312 
313 int
314 udev_dict_delete_key(cdev_t dev, const char *key)
315 {
316 	prop_dictionary_t	dict;
317 
318 	KKASSERT(dev != NULL);
319 
320 	/* Queue a key removal event */
321 	dict = udev_init_dict_event(dev, key);
322 	if (dict == NULL)
323 		return ENOMEM;
324 	udev_event_insert(UDEV_EV_KEY_REMOVE, dict);
325 	prop_object_release(dict);
326 
327 	return _udev_dict_delete_key(dev->si_dict, key);
328 }
329 
330 static int
331 udev_init_dict(cdev_t dev)
332 {
333 	prop_dictionary_t dict;
334 	uint64_t	kptr;
335 	int error;
336 
337 	kptr = (uint64_t)(uintptr_t)dev;
338 
339 	KKASSERT(dev != NULL);
340 
341 	if (dev->si_dict != NULL) {
342 #if 0
343 		log(LOG_DEBUG,
344 		    "udev_init_dict: new dict for %s, but has dict already (%p)!\n",
345 		    dev->si_name, dev->si_dict);
346 #endif
347 		return 0;
348 	}
349 
350 	dict = prop_dictionary_create();
351 	if (dict == NULL) {
352 		log(LOG_DEBUG, "udev_init_dict: prop_dictionary_create() failed\n");
353 		return ENOMEM;
354 	}
355 
356 	if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
357 		goto error_out;
358 	if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
359 		goto error_out;
360 	if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
361 		goto error_out;
362 	if ((error = _udev_dict_set_uint(dict, "devtype", (dev_dflags(dev) & D_TYPEMASK))))
363 		goto error_out;
364 
365 	/* XXX: The next 3 are marginallly useful, if at all */
366 	if ((error = _udev_dict_set_uint(dict, "uid", dev->si_uid)))
367 		goto error_out;
368 	if ((error = _udev_dict_set_uint(dict, "gid", dev->si_gid)))
369 		goto error_out;
370 	if ((error = _udev_dict_set_int(dict, "mode", dev->si_perms)))
371 		goto error_out;
372 
373 	if ((error = _udev_dict_set_int(dict, "major", umajor(dev->si_inode))))
374 		goto error_out;
375 	if ((error = _udev_dict_set_int(dict, "minor", dev->si_uminor)))
376 		goto error_out;
377 	if (dev->si_ops->head.name != NULL) {
378 		if ((error = _udev_dict_set_cstr(dict, "driver",
379 		    __DECONST(char *, dev->si_ops->head.name))))
380 			goto error_out;
381 	}
382 
383 	dev->si_dict = dict;
384 	return 0;
385 
386 error_out:
387 	dev->si_dict = NULL;
388 	prop_object_release(dict);
389 	return error;
390 }
391 
392 static int
393 udev_destroy_dict(cdev_t dev)
394 {
395 	KKASSERT(dev != NULL);
396 
397 	if (dev->si_dict != NULL) {
398 		prop_object_release(dev->si_dict);
399 		dev->si_dict = NULL;
400 	}
401 
402 	return 0;
403 }
404 
405 static void
406 udev_event_insert(int ev_type, prop_dictionary_t dict)
407 {
408 	struct udev_event_kernel *ev;
409 
410 	/* Only start queing events after client has initiated properly */
411 	if (!udevctx.initiated)
412 		return;
413 
414 	/* XXX: use objcache eventually */
415 	ev = kmalloc(sizeof(*ev), M_UDEV, M_WAITOK);
416 	ev->ev.ev_dict = prop_dictionary_copy(dict);
417 	if (ev->ev.ev_dict == NULL) {
418 		kfree(ev, M_UDEV);
419 		return;
420 	}
421 	ev->ev.ev_type = ev_type;
422 
423 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
424 	TAILQ_INSERT_TAIL(&udevctx.ev_queue, ev, link);
425 	++udevctx.qlen;
426 	lockmgr(&udevctx.lock, LK_RELEASE);
427 
428 	wakeup(&udevctx);
429 	KNOTE(&udevctx.kq.ki_note, 0);
430 }
431 
432 static struct udev_event_kernel *
433 udev_event_remove(void)
434 {
435 	struct udev_event_kernel *ev;
436 
437 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
438 	if (TAILQ_EMPTY(&udevctx.ev_queue)) {
439 		lockmgr(&udevctx.lock, LK_RELEASE);
440 		return NULL;
441 	}
442 
443 	ev = TAILQ_FIRST(&udevctx.ev_queue);
444 	TAILQ_REMOVE(&udevctx.ev_queue, ev, link);
445 	--udevctx.qlen;
446 	lockmgr(&udevctx.lock, LK_RELEASE);
447 
448 	return ev;
449 }
450 
451 static void
452 udev_event_free(struct udev_event_kernel *ev)
453 {
454 	/* XXX: use objcache eventually */
455 	kfree(ev, M_UDEV);
456 }
457 
458 static char *
459 udev_event_externalize(struct udev_event_kernel *ev)
460 {
461 	prop_dictionary_t	dict;
462 	char *xml;
463 	int error;
464 
465 
466 	dict = prop_dictionary_create();
467 	if (dict == NULL) {
468 		log(LOG_DEBUG, "udev_event_externalize: prop_dictionary_create() failed\n");
469 		return NULL;
470 	}
471 
472 	if ((error = _udev_dict_set_int(dict, "evtype", ev->ev.ev_type))) {
473 		prop_object_release(dict);
474 		return NULL;
475 	}
476 
477 	if (prop_dictionary_set(dict, "evdict", ev->ev.ev_dict) == false) {
478 		prop_object_release(dict);
479 		return NULL;
480 	}
481 
482 	prop_object_release(ev->ev.ev_dict);
483 
484 	xml = prop_dictionary_externalize(dict);
485 
486 	prop_object_release(dict);
487 
488 	return xml;
489 }
490 
491 int
492 udev_event_attach(cdev_t dev, char *name, int alias)
493 {
494 	prop_dictionary_t	dict;
495 	int error;
496 
497 	KKASSERT(dev != NULL);
498 
499 	error = ENOMEM;
500 
501 	if (alias) {
502 		dict = prop_dictionary_copy(dev->si_dict);
503 		if (dict == NULL)
504 			goto error_out;
505 
506 		if ((error = _udev_dict_set_cstr(dict, "name", name))) {
507 			prop_object_release(dict);
508 			goto error_out;
509 		}
510 
511 		_udev_dict_set_int(dict, "alias", 1);
512 
513 		udev_event_insert(UDEV_EVENT_ATTACH, dict);
514 		prop_object_release(dict);
515 	} else {
516 		error = udev_init_dict(dev);
517 		if (error)
518 			goto error_out;
519 
520 		_udev_dict_set_int(dev->si_dict, "alias", 0);
521 		udev_event_insert(UDEV_EVENT_ATTACH, dev->si_dict);
522 	}
523 
524 error_out:
525 	return error;
526 }
527 
528 int
529 udev_event_detach(cdev_t dev, char *name, int alias)
530 {
531 	prop_dictionary_t	dict;
532 
533 	KKASSERT(dev != NULL);
534 
535 	if (alias) {
536 		dict = prop_dictionary_copy(dev->si_dict);
537 		if (dict == NULL)
538 			goto error_out;
539 
540 		if (_udev_dict_set_cstr(dict, "name", name)) {
541 			prop_object_release(dict);
542 			goto error_out;
543 		}
544 
545 		_udev_dict_set_int(dict, "alias", 1);
546 
547 		udev_event_insert(UDEV_EVENT_DETACH, dict);
548 		prop_object_release(dict);
549 	} else {
550 		udev_event_insert(UDEV_EVENT_DETACH, dev->si_dict);
551 	}
552 
553 error_out:
554 	udev_destroy_dict(dev);
555 
556 	return 0;
557 }
558 
559 /*
560  * dev stuff
561  */
562 static int
563 udev_dev_open(struct dev_open_args *ap)
564 {
565 	if (udevctx.opened)
566 		return EBUSY;
567 
568 	udevctx.opened = 1;
569 
570 	return 0;
571 }
572 
573 static int
574 udev_dev_close(struct dev_close_args *ap)
575 {
576 	udevctx.opened = 0;
577 	udevctx.initiated = 0;
578 	wakeup(&udevctx);
579 
580 	return 0;
581 }
582 
583 static struct filterops udev_dev_read_filtops =
584 	{ FILTEROP_ISFD, NULL, udev_dev_filter_detach, udev_dev_filter_read };
585 
586 static int
587 udev_dev_kqfilter(struct dev_kqfilter_args *ap)
588 {
589 	struct knote *kn = ap->a_kn;
590 	struct klist *klist;
591 
592 	ap->a_result = 0;
593 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
594 
595 	switch (kn->kn_filter) {
596 	case EVFILT_READ:
597 		kn->kn_fop = &udev_dev_read_filtops;
598 		break;
599 	default:
600 		ap->a_result = EOPNOTSUPP;
601 	        lockmgr(&udevctx.lock, LK_RELEASE);
602 		return (0);
603 	}
604 
605 	klist = &udevctx.kq.ki_note;
606 	knote_insert(klist, kn);
607 
608         lockmgr(&udevctx.lock, LK_RELEASE);
609 
610 	return (0);
611 }
612 
613 static void
614 udev_dev_filter_detach(struct knote *kn)
615 {
616 	struct klist *klist;
617 
618 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
619 	klist = &udevctx.kq.ki_note;
620 	knote_remove(klist, kn);
621 	lockmgr(&udevctx.lock, LK_RELEASE);
622 }
623 
624 static int
625 udev_dev_filter_read(struct knote *kn, long hint)
626 {
627 	int ready = 0;
628 
629 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
630 	if (!TAILQ_EMPTY(&udevctx.ev_queue))
631 		ready = 1;
632 	lockmgr(&udevctx.lock, LK_RELEASE);
633 
634 	return (ready);
635 }
636 
637 static int
638 udev_dev_read(struct dev_read_args *ap)
639 {
640 	struct udev_event_kernel *ev;
641 	struct uio *uio = ap->a_uio;
642 	char	*xml;
643 	size_t	len;
644 	int	error;
645 
646 
647 	lockmgr(&udevctx.lock, LK_EXCLUSIVE);
648 
649 	for (;;) {
650 		if ((ev = udev_event_remove()) != NULL) {
651 			if ((xml = udev_event_externalize(ev)) == NULL) {
652 				lockmgr(&udevctx.lock, LK_RELEASE);
653 				return ENOMEM;
654 			}
655 
656 			len = strlen(xml) + 1; /* account for NULL-termination */
657 			if (uio->uio_resid < len) {
658 				error = ENOMEM;
659 			} else {
660 				error = uiomove((caddr_t)xml, len, uio);
661 			}
662 
663 			kfree(xml, M_TEMP);
664 			udev_event_free(ev);
665 			lockmgr(&udevctx.lock, LK_RELEASE);
666 			return error;
667 		}
668 
669 		if ((error = lksleep(&udevctx, &udevctx.lock, 0, "udevq", 0))) {
670 			lockmgr(&udevctx.lock, LK_RELEASE);
671 			return error;
672 		}
673 	}
674 
675 	lockmgr(&udevctx.lock, LK_RELEASE);
676 
677 }
678 
679 static int
680 udev_dev_ioctl(struct dev_ioctl_args *ap)
681 {
682 	prop_dictionary_t dict;
683 	prop_object_t	po;
684 	prop_string_t	ps;
685 	struct plistref *pref;
686 	int i, error;
687 
688 	error = 0;
689 
690 	switch(ap->a_cmd) {
691 	case UDEVPROP:
692 		/* Use proplib(3) for userspace/kernel communication */
693 		pref = (struct plistref *)ap->a_data;
694 		error = prop_dictionary_copyin_ioctl(pref, ap->a_cmd, &dict);
695 		if (error)
696 			return error;
697 
698 		po = prop_dictionary_get(dict, "command");
699 		if (po == NULL || prop_object_type(po) != PROP_TYPE_STRING) {
700 			log(LOG_DEBUG, "udev: prop_dictionary_get() failed\n");
701 			prop_object_release(dict);
702 			return EINVAL;
703 		}
704 
705 		ps = po;
706 		/* Handle cmd */
707 		for(i = 0; cmd_fn[i].cmd != NULL; i++) {
708 			if (prop_string_equals_cstring(ps, cmd_fn[i].cmd))
709 				break;
710 		}
711 
712 		if (cmd_fn[i].cmd != NULL) {
713 			error = cmd_fn[i].fn(pref, ap->a_cmd, dict);
714 		} else {
715 			error = EINVAL;
716 		}
717 
718 		//prop_object_release(po);
719 		prop_object_release(dict);
720 		break;
721 	default:
722 		error = ENOTTY; /* Inappropriate ioctl for device */
723 		break;
724 	}
725 
726 	return(error);
727 }
728 
729 static void
730 udev_getdevs_scan_callback(cdev_t cdev, void *arg)
731 {
732 	struct udev_prop_ctx *ctx = arg;
733 
734 	KKASSERT(arg != NULL);
735 
736 	if (cdev->si_dict == NULL)
737 		return;
738 
739 	if (prop_array_add(ctx->cdevs, cdev->si_dict) == false) {
740 		ctx->error = EINVAL;
741 		return;
742 	}
743 }
744 
745 static int
746 udev_getdevs_ioctl(struct plistref *pref, u_long cmd, prop_dictionary_t dict)
747 {
748 	prop_dictionary_t odict;
749 	struct udev_prop_ctx ctx;
750 	int error;
751 
752 	ctx.error = 0;
753 	ctx.cdevs = prop_array_create();
754 	if (ctx.cdevs == NULL) {
755 		log(LOG_DEBUG, "udev_getdevs_ioctl: prop_array_create() failed\n");
756 		return EINVAL;
757 	}
758 
759 	/* XXX: need devfs_scan_alias_callback() */
760 	devfs_scan_callback(udev_getdevs_scan_callback, &ctx);
761 
762 	if (ctx.error != 0) {
763 		prop_object_release(ctx.cdevs);
764 		return (ctx.error);
765 	}
766 	udevctx.initiated = 1;
767 
768 	odict = prop_dictionary_create();
769 	if (odict == NULL) {
770 		return ENOMEM;
771 	}
772 
773 	if ((prop_dictionary_set(odict, "array", ctx.cdevs)) == 0) {
774 		log(LOG_DEBUG, "udev_getdevs_ioctl: prop_dictionary_set failed\n");
775 		prop_object_release(odict);
776 		return ENOMEM;
777 	}
778 
779 	error = prop_dictionary_copyout_ioctl(pref, cmd, odict);
780 
781 	prop_object_release(odict);
782 	return error;
783 }
784 
785 
786 /*
787  * SYSINIT stuff
788  */
789 static void
790 udev_init(void)
791 {
792 	lockinit(&udevctx.lock, "udevevq", 0, LK_CANRECURSE);
793 	TAILQ_INIT(&udevctx.ev_queue);
794 }
795 
796 static void
797 udev_uninit(void)
798 {
799 }
800 
801 static void
802 udev_dev_init(void)
803 {
804 	udev_dev = make_dev(&udev_dev_ops,
805             0,
806             UID_ROOT,
807             GID_WHEEL,
808             0600,
809             "udev");
810 }
811 
812 static void
813 udev_dev_uninit(void)
814 {
815 	destroy_dev(udev_dev);
816 }
817 
818 SYSINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY, udev_init, NULL);
819 SYSUNINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY, udev_uninit, NULL);
820 SYSINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY, udev_dev_init, NULL);
821 SYSUNINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY, udev_dev_uninit, NULL);
822