xref: /dragonfly/sys/kern/kern_udev.c (revision f503b4c4)
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/vnode.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 static d_clone_t	udev_dev_clone;
62 
63 struct udev_prop_ctx {
64 	prop_array_t cdevs;
65 	int error;
66 };
67 
68 struct udev_event_kernel {
69 	struct udev_event ev;
70 	TAILQ_ENTRY(udev_event_kernel)	link;
71 };
72 
73 struct udev_softc {
74 	TAILQ_ENTRY(udev_softc) entry;
75 	int opened;
76 	int initiated;
77 	int unit;
78 	cdev_t dev;
79 
80 	struct udev_event_kernel marker;	/* udev_evq marker */
81 };
82 
83 struct cmd_function {
84 	const char *cmd;
85 	int  (*fn)(struct udev_softc *, struct plistref *,
86 		   u_long, prop_dictionary_t);
87 };
88 
89 
90 static int _udev_dict_set_cstr(prop_dictionary_t, const char *, char *);
91 static int _udev_dict_set_int(prop_dictionary_t, const char *, int64_t);
92 static int _udev_dict_set_uint(prop_dictionary_t, const char *, uint64_t);
93 static int _udev_dict_delete_key(prop_dictionary_t, const char *);
94 static prop_dictionary_t udev_init_dict_event(cdev_t, const char *);
95 static int udev_init_dict(cdev_t);
96 static int udev_destroy_dict(cdev_t);
97 static void udev_event_insert(int, prop_dictionary_t);
98 static void udev_clean_events_locked(void);
99 static char *udev_event_externalize(struct udev_event_kernel *);
100 static void udev_getdevs_scan_callback(char *, cdev_t, bool, void *);
101 static int udev_getdevs_ioctl(struct udev_softc *, struct plistref *,
102 					u_long, prop_dictionary_t);
103 static void udev_dev_filter_detach(struct knote *);
104 static int udev_dev_filter_read(struct knote *, long);
105 
106 static struct dev_ops udev_dev_ops = {
107 	{ "udev", 0, 0 },
108 	.d_open = udev_dev_open,
109 	.d_close = udev_dev_close,
110 	.d_read = udev_dev_read,
111 	.d_kqfilter = udev_dev_kqfilter,
112 	.d_ioctl = udev_dev_ioctl
113 };
114 
115 static struct cmd_function cmd_fn[] = {
116 		{ .cmd = "getdevs", .fn = udev_getdevs_ioctl},
117 		{NULL, NULL}
118 };
119 
120 DEVFS_DECLARE_CLONE_BITMAP(udev);
121 
122 static TAILQ_HEAD(, udev_softc) udevq;
123 static TAILQ_HEAD(, udev_event_kernel) udev_evq;
124 static struct kqinfo udev_kq;
125 static struct lock udev_lk;
126 static int udev_evqlen;
127 static int udev_initiated_count;
128 static int udev_open_count;
129 static int udev_seqwait;
130 static int udev_seq;
131 
132 static int
133 _udev_dict_set_cstr(prop_dictionary_t dict, const char *key, char *str)
134 {
135 	prop_string_t	ps;
136 
137 	KKASSERT(dict != NULL);
138 
139 	ps = prop_string_create_cstring(str);
140 	if (ps == NULL) {
141 		return ENOMEM;
142 	}
143 
144 	if (prop_dictionary_set(dict, key, ps) == false) {
145 		prop_object_release(ps);
146 		return ENOMEM;
147 	}
148 
149 	prop_object_release(ps);
150 	return 0;
151 }
152 
153 static int
154 _udev_dict_set_int(prop_dictionary_t dict, const char *key, int64_t val)
155 {
156 	prop_number_t	pn;
157 
158 	KKASSERT(dict != NULL);
159 
160 	pn = prop_number_create_integer(val);
161 	if (pn == NULL)
162 		return ENOMEM;
163 
164 	if (prop_dictionary_set(dict, key, pn) == false) {
165 		prop_object_release(pn);
166 		return ENOMEM;
167 	}
168 
169 	prop_object_release(pn);
170 	return 0;
171 }
172 
173 static int
174 _udev_dict_set_uint(prop_dictionary_t dict, const char *key, uint64_t val)
175 {
176 	prop_number_t	pn;
177 
178 	KKASSERT(dict != NULL);
179 
180 	pn = prop_number_create_unsigned_integer(val);
181 	if (pn == NULL)
182 		return ENOMEM;
183 
184 	if (prop_dictionary_set(dict, key, pn) == false) {
185 		prop_object_release(pn);
186 		return ENOMEM;
187 	}
188 
189 	prop_object_release(pn);
190 	return 0;
191 }
192 
193 static int
194 _udev_dict_delete_key(prop_dictionary_t dict, const char *key)
195 {
196 	KKASSERT(dict != NULL);
197 
198 	prop_dictionary_remove(dict, key);
199 
200 	return 0;
201 }
202 
203 /*
204  * Initialize an event dictionary, which contains three parameters to
205  * identify the device referred to (name, devnum, kptr) and the affected key.
206  */
207 static prop_dictionary_t
208 udev_init_dict_event(cdev_t dev, const char *key)
209 {
210 	prop_dictionary_t	dict;
211 	uint64_t	kptr;
212 	int error;
213 
214 	kptr = (uint64_t)(uintptr_t)dev;
215 	KKASSERT(dev != NULL);
216 
217 	dict = prop_dictionary_create();
218 	if (dict == NULL) {
219 		log(LOG_DEBUG, "udev_init_dict_event: prop_dictionary_create() failed\n");
220 		return NULL;
221 	}
222 
223 	if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
224 		goto error_out;
225 	if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
226 		goto error_out;
227 	if ((error = _udev_dict_set_uint(dict, "devtype", (dev_dflags(dev) & D_TYPEMASK))))
228 		goto error_out;
229 	if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
230 		goto error_out;
231 	if ((error = _udev_dict_set_cstr(dict, "key", __DECONST(char *, key))))
232 		goto error_out;
233 
234 	return dict;
235 
236 error_out:
237 	prop_object_release(dict);
238 	return NULL;
239 }
240 
241 int
242 udev_dict_set_cstr(cdev_t dev, const char *key, char *str)
243 {
244 	prop_dictionary_t	dict;
245 	int error;
246 
247 	KKASSERT(dev != NULL);
248 
249 	if (dev->si_dict == NULL) {
250 		error = udev_init_dict(dev);
251 		if (error)
252 			return -1;
253 	}
254 
255 	/* Queue a key update event */
256 	dict = udev_init_dict_event(dev, key);
257 	if (dict == NULL)
258 		return ENOMEM;
259 
260 	if ((error = _udev_dict_set_cstr(dict, "value", str))) {
261 		prop_object_release(dict);
262 		return error;
263 	}
264 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
265 	prop_object_release(dict);
266 
267 	error = _udev_dict_set_cstr(dev->si_dict, key, str);
268 	return error;
269 }
270 
271 int
272 udev_dict_set_int(cdev_t dev, const char *key, int64_t val)
273 {
274 	prop_dictionary_t	dict;
275 	int error;
276 
277 	KKASSERT(dev != NULL);
278 
279 	if (dev->si_dict == NULL) {
280 		error = udev_init_dict(dev);
281 		if (error)
282 			return -1;
283 	}
284 
285 	/* Queue a key update event */
286 	dict = udev_init_dict_event(dev, key);
287 	if (dict == NULL)
288 		return ENOMEM;
289 	if ((error = _udev_dict_set_int(dict, "value", val))) {
290 		prop_object_release(dict);
291 		return error;
292 	}
293 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
294 	prop_object_release(dict);
295 
296 	return _udev_dict_set_int(dev->si_dict, key, val);
297 }
298 
299 int
300 udev_dict_set_uint(cdev_t dev, const char *key, uint64_t val)
301 {
302 	prop_dictionary_t	dict;
303 	int error;
304 
305 	KKASSERT(dev != NULL);
306 
307 	if (dev->si_dict == NULL) {
308 		error = udev_init_dict(dev);
309 		if (error)
310 			return -1;
311 	}
312 
313 	/* Queue a key update event */
314 	dict = udev_init_dict_event(dev, key);
315 	if (dict == NULL)
316 		return ENOMEM;
317 	if ((error = _udev_dict_set_uint(dict, "value", val))) {
318 		prop_object_release(dict);
319 		return error;
320 	}
321 	udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
322 	prop_object_release(dict);
323 
324 	return _udev_dict_set_uint(dev->si_dict, key, val);
325 }
326 
327 int
328 udev_dict_delete_key(cdev_t dev, const char *key)
329 {
330 	prop_dictionary_t	dict;
331 
332 	KKASSERT(dev != NULL);
333 
334 	/* Queue a key removal event */
335 	dict = udev_init_dict_event(dev, key);
336 	if (dict == NULL)
337 		return ENOMEM;
338 	udev_event_insert(UDEV_EV_KEY_REMOVE, dict);
339 	prop_object_release(dict);
340 
341 	return _udev_dict_delete_key(dev->si_dict, key);
342 }
343 
344 static int
345 udev_init_dict(cdev_t dev)
346 {
347 	prop_dictionary_t dict;
348 	uint64_t	kptr;
349 	int error;
350 
351 	kptr = (uint64_t)(uintptr_t)dev;
352 
353 	KKASSERT(dev != NULL);
354 
355 	if (dev->si_dict != NULL) {
356 #if 0
357 		log(LOG_DEBUG,
358 		    "udev_init_dict: new dict for %s, but has dict already (%p)!\n",
359 		    dev->si_name, dev->si_dict);
360 #endif
361 		return 0;
362 	}
363 
364 	dict = prop_dictionary_create();
365 	if (dict == NULL) {
366 		log(LOG_DEBUG, "udev_init_dict: prop_dictionary_create() failed\n");
367 		return ENOMEM;
368 	}
369 
370 	if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
371 		goto error_out;
372 	if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
373 		goto error_out;
374 	if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
375 		goto error_out;
376 	if ((error = _udev_dict_set_uint(dict, "devtype", (dev_dflags(dev) & D_TYPEMASK))))
377 		goto error_out;
378 
379 	/* XXX: The next 3 are marginallly useful, if at all */
380 	if ((error = _udev_dict_set_uint(dict, "uid", dev->si_uid)))
381 		goto error_out;
382 	if ((error = _udev_dict_set_uint(dict, "gid", dev->si_gid)))
383 		goto error_out;
384 	if ((error = _udev_dict_set_int(dict, "mode", dev->si_perms)))
385 		goto error_out;
386 
387 	if ((error = _udev_dict_set_int(dict, "major", dev->si_umajor)))
388 		goto error_out;
389 	if ((error = _udev_dict_set_int(dict, "minor", dev->si_uminor)))
390 		goto error_out;
391 	if (dev->si_ops->head.name != NULL) {
392 		if ((error = _udev_dict_set_cstr(dict, "driver",
393 		    __DECONST(char *, dev->si_ops->head.name))))
394 			goto error_out;
395 	}
396 
397 	dev->si_dict = dict;
398 	return 0;
399 
400 error_out:
401 	dev->si_dict = NULL;
402 	prop_object_release(dict);
403 	return error;
404 }
405 
406 static int
407 udev_destroy_dict(cdev_t dev)
408 {
409 	KKASSERT(dev != NULL);
410 
411 	if (dev->si_dict != NULL) {
412 		prop_object_release(dev->si_dict);
413 		dev->si_dict = NULL;
414 	}
415 
416 	return 0;
417 }
418 
419 static void
420 udev_event_insert(int ev_type, prop_dictionary_t dict)
421 {
422 	struct udev_event_kernel *ev;
423 
424 	/* Only start queing events after client has initiated properly */
425 	if (udev_initiated_count) {
426 		/* XXX: use objcache eventually */
427 		ev = kmalloc(sizeof(*ev), M_UDEV, M_WAITOK);
428 		ev->ev.ev_dict = prop_dictionary_copy(dict);
429 		if (ev->ev.ev_dict == NULL) {
430 			kfree(ev, M_UDEV);
431 			return;
432 		}
433 		ev->ev.ev_type = ev_type;
434 
435 		lockmgr(&udev_lk, LK_EXCLUSIVE);
436 		TAILQ_INSERT_TAIL(&udev_evq, ev, link);
437 		++udev_evqlen;
438 		++udev_seq;
439 		if (udev_seqwait)
440 			wakeup(&udev_seqwait);
441 		lockmgr(&udev_lk, LK_RELEASE);
442 		wakeup(&udev_evq);
443 		KNOTE(&udev_kq.ki_note, 0);
444 	} else if (udev_open_count) {
445 		lockmgr(&udev_lk, LK_EXCLUSIVE);
446 		++udev_seq;
447 		if (udev_seqwait)
448 			wakeup(&udev_seqwait);
449 		lockmgr(&udev_lk, LK_RELEASE);
450 		KNOTE(&udev_kq.ki_note, 0);
451 	}
452 }
453 
454 static void
455 udev_clean_events_locked(void)
456 {
457 	struct udev_event_kernel *ev;
458 
459 	while ((ev = TAILQ_FIRST(&udev_evq)) &&
460 	       ev->ev.ev_dict != NULL) {
461 		TAILQ_REMOVE(&udev_evq, ev, link);
462 		kfree(ev, M_UDEV);
463 		--udev_evqlen;
464 	}
465 }
466 
467 static char *
468 udev_event_externalize(struct udev_event_kernel *ev)
469 {
470 	prop_dictionary_t	dict;
471 	char *xml;
472 	int error;
473 
474 
475 	dict = prop_dictionary_create();
476 	if (dict == NULL) {
477 		log(LOG_DEBUG,
478 		    "udev_event_externalize: prop_dictionary_create() failed\n");
479 		return NULL;
480 	}
481 
482 	if ((error = _udev_dict_set_int(dict, "evtype", ev->ev.ev_type))) {
483 		prop_object_release(dict);
484 		return NULL;
485 	}
486 
487 	if (prop_dictionary_set(dict, "evdict", ev->ev.ev_dict) == false) {
488 		prop_object_release(dict);
489 		return NULL;
490 	}
491 
492 	prop_object_release(ev->ev.ev_dict);
493 
494 	xml = prop_dictionary_externalize(dict);
495 
496 	prop_object_release(dict);
497 
498 	return xml;
499 }
500 
501 int
502 udev_event_attach(cdev_t dev, char *name, int alias)
503 {
504 	prop_dictionary_t	dict;
505 	int error;
506 
507 	KKASSERT(dev != NULL);
508 
509 	error = ENOMEM;
510 
511 	if (alias) {
512 		dict = prop_dictionary_copy(dev->si_dict);
513 		if (dict == NULL)
514 			goto error_out;
515 
516 		if ((error = _udev_dict_set_cstr(dict, "name", name))) {
517 			prop_object_release(dict);
518 			goto error_out;
519 		}
520 
521 		_udev_dict_set_int(dict, "alias", 1);
522 
523 		udev_event_insert(UDEV_EVENT_ATTACH, dict);
524 		prop_object_release(dict);
525 	} else {
526 		error = udev_init_dict(dev);
527 		if (error)
528 			goto error_out;
529 
530 		_udev_dict_set_int(dev->si_dict, "alias", 0);
531 		udev_event_insert(UDEV_EVENT_ATTACH, dev->si_dict);
532 	}
533 
534 error_out:
535 	return error;
536 }
537 
538 int
539 udev_event_detach(cdev_t dev, char *name, int alias)
540 {
541 	prop_dictionary_t	dict;
542 
543 	KKASSERT(dev != NULL);
544 
545 	if (alias) {
546 		dict = prop_dictionary_copy(dev->si_dict);
547 		if (dict == NULL)
548 			goto error_out;
549 
550 		if (_udev_dict_set_cstr(dict, "name", name)) {
551 			prop_object_release(dict);
552 			goto error_out;
553 		}
554 
555 		_udev_dict_set_int(dict, "alias", 1);
556 
557 		udev_event_insert(UDEV_EVENT_DETACH, dict);
558 		prop_object_release(dict);
559 	} else {
560 		udev_event_insert(UDEV_EVENT_DETACH, dev->si_dict);
561 	}
562 
563 error_out:
564 	udev_destroy_dict(dev);
565 
566 	return 0;
567 }
568 
569 /*
570  * Allow multiple opens.  Each opener gets a different device.
571  * Messages are replicated to all devices using a marker system.
572  */
573 static int
574 udev_dev_clone(struct dev_clone_args *ap)
575 {
576 	struct udev_softc *softc;
577 	int unit;
578 
579 	unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(udev), 1000);
580 	if (unit < 0) {
581 		ap->a_dev = NULL;
582 		return 1;
583 	}
584 
585 	softc = kmalloc(sizeof(*softc), M_UDEV, M_WAITOK | M_ZERO);
586 	softc->unit = unit;
587 	lockmgr(&udev_lk, LK_EXCLUSIVE);
588 	TAILQ_INSERT_TAIL(&udevq, softc, entry);
589 	lockmgr(&udev_lk, LK_RELEASE);
590 
591 	softc->dev = make_only_dev(&udev_dev_ops, unit, ap->a_cred->cr_ruid,
592 				   0, 0600, "udev/%d", unit);
593 	softc->dev->si_drv1 = softc;
594 	ap->a_dev = softc->dev;
595 	return 0;
596 }
597 
598 /*
599  * dev stuff
600  */
601 static int
602 udev_dev_open(struct dev_open_args *ap)
603 {
604 	struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
605 
606 	lockmgr(&udev_lk, LK_EXCLUSIVE);
607 	if (softc == NULL || softc->opened) {
608 		lockmgr(&udev_lk, LK_RELEASE);
609 		return EBUSY;
610 	}
611 	softc->opened = 1;
612 	++udev_open_count;
613 	lockmgr(&udev_lk, LK_RELEASE);
614 
615 	return 0;
616 }
617 
618 static int
619 udev_dev_close(struct dev_close_args *ap)
620 {
621 	struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
622 
623 	KKASSERT(softc->dev == ap->a_head.a_dev);
624 	KKASSERT(softc->opened == 1);
625 
626 	lockmgr(&udev_lk, LK_EXCLUSIVE);
627 	TAILQ_REMOVE(&udevq, softc, entry);
628 	devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(udev), softc->unit);
629 
630 	if (softc->initiated) {
631 		TAILQ_REMOVE(&udev_evq, &softc->marker, link);
632 		softc->initiated = 0;
633 		--udev_initiated_count;
634 		udev_clean_events_locked();
635 	}
636 	softc->opened = 0;
637 	softc->dev = NULL;
638 	ap->a_head.a_dev->si_drv1 = NULL;
639 	--udev_open_count;
640 	lockmgr(&udev_lk, LK_RELEASE);
641 
642 	destroy_dev(ap->a_head.a_dev);
643 	wakeup(&udev_evq);
644 
645 	kfree(softc, M_UDEV);
646 
647 	return 0;
648 }
649 
650 static struct filterops udev_dev_read_filtops =
651 	{ FILTEROP_ISFD, NULL, udev_dev_filter_detach, udev_dev_filter_read };
652 
653 static int
654 udev_dev_kqfilter(struct dev_kqfilter_args *ap)
655 {
656 	struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
657 	struct knote *kn = ap->a_kn;
658 	struct klist *klist;
659 
660 	ap->a_result = 0;
661 	lockmgr(&udev_lk, LK_EXCLUSIVE);
662 
663 	switch (kn->kn_filter) {
664 	case EVFILT_READ:
665 		kn->kn_fop = &udev_dev_read_filtops;
666 		kn->kn_hook = (caddr_t)softc;
667 		break;
668 	default:
669 		ap->a_result = EOPNOTSUPP;
670 	        lockmgr(&udev_lk, LK_RELEASE);
671 		return (0);
672 	}
673 
674 	klist = &udev_kq.ki_note;
675 	knote_insert(klist, kn);
676 
677         lockmgr(&udev_lk, LK_RELEASE);
678 
679 	return (0);
680 }
681 
682 static void
683 udev_dev_filter_detach(struct knote *kn)
684 {
685 	struct klist *klist;
686 
687 	lockmgr(&udev_lk, LK_EXCLUSIVE);
688 	klist = &udev_kq.ki_note;
689 	knote_remove(klist, kn);
690 	lockmgr(&udev_lk, LK_RELEASE);
691 }
692 
693 static int
694 udev_dev_filter_read(struct knote *kn, long hint)
695 {
696 	struct udev_softc *softc = (void *)kn->kn_hook;
697 	struct udev_event_kernel *ev;
698 	int ready = 0;
699 
700 	lockmgr(&udev_lk, LK_EXCLUSIVE);
701 	if (softc->initiated) {
702 		ev = TAILQ_NEXT(&softc->marker, link);
703 		while (ev && ev->ev.ev_dict == NULL)
704 			ev = TAILQ_NEXT(ev, link);
705 		if (ev)
706 			ready = 1;
707 	}
708 	lockmgr(&udev_lk, LK_RELEASE);
709 
710 	return (ready);
711 }
712 
713 static int
714 udev_dev_read(struct dev_read_args *ap)
715 {
716 	struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
717 	struct udev_event_kernel *ev;
718 	struct uio *uio = ap->a_uio;
719 	char	*xml;
720 	size_t	len;
721 	int	error;
722 
723 	lockmgr(&udev_lk, LK_EXCLUSIVE);
724 
725 	/*
726 	 * Automatically enable message collection if it has not already
727 	 * been enabled.
728 	 */
729 	if (softc->initiated == 0) {
730 		softc->initiated = 1;
731 		++udev_initiated_count;
732 		TAILQ_INSERT_HEAD(&udev_evq, &softc->marker, link);
733 	}
734 
735 	/*
736 	 * Loop, sleep interruptably until we get an event or signal.
737 	 */
738 	error = 0;
739 	for (;;) {
740 		if (softc->initiated) {
741 			ev = TAILQ_NEXT(&softc->marker, link);
742 			while (ev && ev->ev.ev_dict == NULL)
743 				ev = TAILQ_NEXT(ev, link);
744 			if (ev) {
745 				if ((xml = udev_event_externalize(ev)) == NULL) {
746 					error = ENOMEM;
747 					break;
748 				}
749 				len = strlen(xml) + 1; /* include terminator */
750 				if (uio->uio_resid < len)
751 					error = ENOMEM;
752 				else
753 					error = uiomove((caddr_t)xml, len, uio);
754 				kfree(xml, M_TEMP);
755 
756 				/*
757 				 * Move the marker
758 				 */
759 				TAILQ_REMOVE(&udev_evq, &softc->marker, link);
760 				TAILQ_INSERT_AFTER(&udev_evq,
761 						   ev, &softc->marker, link);
762 				udev_clean_events_locked();
763 				break;
764 			}
765 		}
766 		if (ap->a_ioflag & IO_NDELAY) {
767 			error = EWOULDBLOCK;
768 			break;
769 		}
770 		if ((error = lksleep(&udev_evq, &udev_lk, PCATCH, "udevq", 0)))
771 			break;
772 	}
773 
774 	lockmgr(&udev_lk, LK_RELEASE);
775 	return error;
776 }
777 
778 static int
779 udev_dev_ioctl(struct dev_ioctl_args *ap)
780 {
781 	struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
782 	prop_dictionary_t dict;
783 	prop_object_t	po;
784 	prop_string_t	ps;
785 	struct plistref *pref;
786 	int i, error;
787 	int seq;
788 
789 	error = 0;
790 
791 	switch(ap->a_cmd) {
792 	case UDEVPROP:
793 		/* Use proplib(3) for userspace/kernel communication */
794 		pref = (struct plistref *)ap->a_data;
795 		error = prop_dictionary_copyin_ioctl(pref, ap->a_cmd, &dict);
796 		if (error)
797 			return error;
798 
799 		po = prop_dictionary_get(dict, "command");
800 		if (po == NULL || prop_object_type(po) != PROP_TYPE_STRING) {
801 			log(LOG_DEBUG, "udev: prop_dictionary_get() failed\n");
802 			prop_object_release(dict);
803 			return EINVAL;
804 		}
805 
806 		ps = po;
807 		/* Handle cmd */
808 		for(i = 0; cmd_fn[i].cmd != NULL; i++) {
809 			if (prop_string_equals_cstring(ps, cmd_fn[i].cmd))
810 				break;
811 		}
812 
813 		if (cmd_fn[i].cmd != NULL) {
814 			error = cmd_fn[i].fn(softc, pref, ap->a_cmd, dict);
815 		} else {
816 			error = EINVAL;
817 		}
818 
819 		//prop_object_release(po);
820 		prop_object_release(dict);
821 		break;
822 	case UDEVWAIT:
823 		/*
824 		 * Wait for events based on sequence number.  Updates
825 		 * sequence number for loop.
826 		 */
827 		lockmgr(&udev_lk, LK_EXCLUSIVE);
828 		seq = *(int *)ap->a_data;
829 		++udev_seqwait;
830 		while (seq == udev_seq) {
831 			error = lksleep(&udev_seqwait, &udev_lk,
832 					PCATCH, "udevw", 0);
833 			if (error)
834 				break;
835 		}
836 		--udev_seqwait;
837 		*(int *)ap->a_data = udev_seq;
838 		lockmgr(&udev_lk, LK_RELEASE);
839 		break;
840 	default:
841 		error = ENOTTY; /* Inappropriate ioctl for device */
842 		break;
843 	}
844 
845 	return(error);
846 }
847 
848 static void
849 udev_getdevs_scan_callback(char *name, cdev_t cdev, bool is_alias, void *arg)
850 {
851 	struct udev_prop_ctx *ctx = arg;
852 
853 	KKASSERT(arg != NULL);
854 
855 	if (cdev->si_dict == NULL)
856 		return;
857 
858 	if (prop_array_add(ctx->cdevs, cdev->si_dict) == false) {
859 		ctx->error = EINVAL;
860 		return;
861 	}
862 }
863 
864 static int
865 udev_getdevs_ioctl(struct udev_softc *softc, struct plistref *pref,
866 		   u_long cmd, prop_dictionary_t dict)
867 {
868 	prop_dictionary_t odict;
869 	struct udev_prop_ctx ctx;
870 	int error;
871 
872 	/*
873 	 * Ensure event notification is enabled before doing the devfs
874 	 * scan so nothing gets missed.
875 	 */
876 	lockmgr(&udev_lk, LK_EXCLUSIVE);
877 	if (softc->initiated == 0) {
878 		softc->initiated = 1;
879 		++udev_initiated_count;
880 		TAILQ_INSERT_HEAD(&udev_evq, &softc->marker, link);
881 	}
882 	lockmgr(&udev_lk, LK_RELEASE);
883 
884 	/*
885 	 * Devfs scan to build full dictionary.
886 	 */
887 	ctx.error = 0;
888 	ctx.cdevs = prop_array_create();
889 	if (ctx.cdevs == NULL) {
890 		log(LOG_DEBUG,
891 		    "udev_getdevs_ioctl: prop_array_create() failed\n");
892 		return EINVAL;
893 	}
894 
895 	devfs_scan_callback(udev_getdevs_scan_callback, &ctx);
896 
897 	if (ctx.error != 0) {
898 		prop_object_release(ctx.cdevs);
899 		return (ctx.error);
900 	}
901 
902 	odict = prop_dictionary_create();
903 	if (odict == NULL) {
904 		return ENOMEM;
905 	}
906 
907 	if ((prop_dictionary_set(odict, "array", ctx.cdevs)) == 0) {
908 		log(LOG_DEBUG,
909 		    "udev_getdevs_ioctl: prop_dictionary_set failed\n");
910 		prop_object_release(odict);
911 		return ENOMEM;
912 	}
913 
914 	error = prop_dictionary_copyout_ioctl(pref, cmd, odict);
915 
916 	prop_object_release(odict);
917 	return error;
918 }
919 
920 
921 /*
922  * SYSINIT stuff
923  */
924 static void
925 udev_init(void)
926 {
927 	lockinit(&udev_lk, "udevlk", 0, LK_CANRECURSE);
928 	TAILQ_INIT(&udevq);
929 	TAILQ_INIT(&udev_evq);
930 }
931 
932 static void
933 udev_uninit(void)
934 {
935 }
936 
937 static void
938 udev_dev_init(void)
939 {
940 	udev_dev = make_autoclone_dev(&udev_dev_ops, &DEVFS_CLONE_BITMAP(udev),
941 				      udev_dev_clone,
942 				      UID_ROOT, GID_WHEEL, 0600, "udev");
943 }
944 
945 static void
946 udev_dev_uninit(void)
947 {
948 	destroy_dev(udev_dev);
949 }
950 
951 SYSINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY,
952 	udev_init, NULL);
953 SYSUNINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY,
954 	udev_uninit, NULL);
955 SYSINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
956 	udev_dev_init, NULL);
957 SYSUNINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
958 	udev_dev_uninit, NULL);
959