xref: /freebsd/sys/kern/subr_bus.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*-
2  * Copyright (c) 1997,1998,2003 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_bus.h"
31 
32 #include <sys/param.h>
33 #include <sys/conf.h>
34 #include <sys/filio.h>
35 #include <sys/lock.h>
36 #include <sys/kernel.h>
37 #include <sys/kobj.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/poll.h>
42 #include <sys/proc.h>
43 #include <sys/condvar.h>
44 #include <sys/queue.h>
45 #include <machine/bus.h>
46 #include <sys/rman.h>
47 #include <sys/selinfo.h>
48 #include <sys/signalvar.h>
49 #include <sys/sysctl.h>
50 #include <sys/systm.h>
51 #include <sys/uio.h>
52 #include <sys/bus.h>
53 #include <sys/interrupt.h>
54 
55 #include <machine/stdarg.h>
56 
57 #include <vm/uma.h>
58 
59 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW, NULL, NULL);
60 SYSCTL_NODE(, OID_AUTO, dev, CTLFLAG_RW, NULL, NULL);
61 
62 /*
63  * Used to attach drivers to devclasses.
64  */
65 typedef struct driverlink *driverlink_t;
66 struct driverlink {
67 	kobj_class_t	driver;
68 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
69 };
70 
71 /*
72  * Forward declarations
73  */
74 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
75 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
76 typedef TAILQ_HEAD(device_list, device) device_list_t;
77 
78 struct devclass {
79 	TAILQ_ENTRY(devclass) link;
80 	devclass_t	parent;		/* parent in devclass hierarchy */
81 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
82 	char		*name;
83 	device_t	*devices;	/* array of devices indexed by unit */
84 	int		maxunit;	/* size of devices array */
85 
86 	struct sysctl_ctx_list sysctl_ctx;
87 	struct sysctl_oid *sysctl_tree;
88 };
89 
90 /**
91  * @brief Implementation of device.
92  */
93 struct device {
94 	/*
95 	 * A device is a kernel object. The first field must be the
96 	 * current ops table for the object.
97 	 */
98 	KOBJ_FIELDS;
99 
100 	/*
101 	 * Device hierarchy.
102 	 */
103 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
104 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
105 	device_t	parent;		/**< parent of this device  */
106 	device_list_t	children;	/**< list of child devices */
107 
108 	/*
109 	 * Details of this device.
110 	 */
111 	driver_t	*driver;	/**< current driver */
112 	devclass_t	devclass;	/**< current device class */
113 	int		unit;		/**< current unit number */
114 	char*		nameunit;	/**< name+unit e.g. foodev0 */
115 	char*		desc;		/**< driver specific description */
116 	int		busy;		/**< count of calls to device_busy() */
117 	device_state_t	state;		/**< current device state  */
118 	u_int32_t	devflags;	/**< api level flags for device_get_flags() */
119 	u_short		flags;		/**< internal device flags  */
120 #define	DF_ENABLED	1		/* device should be probed/attached */
121 #define	DF_FIXEDCLASS	2		/* devclass specified at create time */
122 #define	DF_WILDCARD	4		/* unit was originally wildcard */
123 #define	DF_DESCMALLOCED	8		/* description was malloced */
124 #define	DF_QUIET	16		/* don't print verbose attach message */
125 #define	DF_DONENOMATCH	32		/* don't execute DEVICE_NOMATCH again */
126 #define	DF_EXTERNALSOFTC 64		/* softc not allocated by us */
127 #define	DF_REBID	128		/* Can rebid after attach */
128 	u_char	order;			/**< order from device_add_child_ordered() */
129 	u_char	pad;
130 	void	*ivars;			/**< instance variables  */
131 	void	*softc;			/**< current driver's variables  */
132 
133 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
134 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
135 };
136 
137 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
138 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
139 
140 #ifdef BUS_DEBUG
141 
142 static int bus_debug = 1;
143 TUNABLE_INT("bus.debug", &bus_debug);
144 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RW, &bus_debug, 0,
145     "Debug bus code");
146 
147 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
148 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
149 #define DRIVERNAME(d)	((d)? d->name : "no driver")
150 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
151 
152 /**
153  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
154  * prevent syslog from deleting initial spaces
155  */
156 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
157 
158 static void print_device_short(device_t dev, int indent);
159 static void print_device(device_t dev, int indent);
160 void print_device_tree_short(device_t dev, int indent);
161 void print_device_tree(device_t dev, int indent);
162 static void print_driver_short(driver_t *driver, int indent);
163 static void print_driver(driver_t *driver, int indent);
164 static void print_driver_list(driver_list_t drivers, int indent);
165 static void print_devclass_short(devclass_t dc, int indent);
166 static void print_devclass(devclass_t dc, int indent);
167 void print_devclass_list_short(void);
168 void print_devclass_list(void);
169 
170 #else
171 /* Make the compiler ignore the function calls */
172 #define PDEBUG(a)			/* nop */
173 #define DEVICENAME(d)			/* nop */
174 #define DRIVERNAME(d)			/* nop */
175 #define DEVCLANAME(d)			/* nop */
176 
177 #define print_device_short(d,i)		/* nop */
178 #define print_device(d,i)		/* nop */
179 #define print_device_tree_short(d,i)	/* nop */
180 #define print_device_tree(d,i)		/* nop */
181 #define print_driver_short(d,i)		/* nop */
182 #define print_driver(d,i)		/* nop */
183 #define print_driver_list(d,i)		/* nop */
184 #define print_devclass_short(d,i)	/* nop */
185 #define print_devclass(d,i)		/* nop */
186 #define print_devclass_list_short()	/* nop */
187 #define print_devclass_list()		/* nop */
188 #endif
189 
190 /*
191  * dev sysctl tree
192  */
193 
194 enum {
195 	DEVCLASS_SYSCTL_PARENT,
196 };
197 
198 static int
199 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
200 {
201 	devclass_t dc = (devclass_t)arg1;
202 	const char *value;
203 
204 	switch (arg2) {
205 	case DEVCLASS_SYSCTL_PARENT:
206 		value = dc->parent ? dc->parent->name : "";
207 		break;
208 	default:
209 		return (EINVAL);
210 	}
211 	return (SYSCTL_OUT(req, value, strlen(value)));
212 }
213 
214 static void
215 devclass_sysctl_init(devclass_t dc)
216 {
217 
218 	if (dc->sysctl_tree != NULL)
219 		return;
220 	sysctl_ctx_init(&dc->sysctl_ctx);
221 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
222 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
223 	    CTLFLAG_RD, 0, "");
224 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
225 	    OID_AUTO, "%parent", CTLFLAG_RD,
226 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
227 	    "parent class");
228 }
229 
230 enum {
231 	DEVICE_SYSCTL_DESC,
232 	DEVICE_SYSCTL_DRIVER,
233 	DEVICE_SYSCTL_LOCATION,
234 	DEVICE_SYSCTL_PNPINFO,
235 	DEVICE_SYSCTL_PARENT,
236 };
237 
238 static int
239 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
240 {
241 	device_t dev = (device_t)arg1;
242 	const char *value;
243 	char *buf;
244 	int error;
245 
246 	buf = NULL;
247 	switch (arg2) {
248 	case DEVICE_SYSCTL_DESC:
249 		value = dev->desc ? dev->desc : "";
250 		break;
251 	case DEVICE_SYSCTL_DRIVER:
252 		value = dev->driver ? dev->driver->name : "";
253 		break;
254 	case DEVICE_SYSCTL_LOCATION:
255 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
256 		bus_child_location_str(dev, buf, 1024);
257 		break;
258 	case DEVICE_SYSCTL_PNPINFO:
259 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
260 		bus_child_pnpinfo_str(dev, buf, 1024);
261 		break;
262 	case DEVICE_SYSCTL_PARENT:
263 		value = dev->parent ? dev->parent->nameunit : "";
264 		break;
265 	default:
266 		return (EINVAL);
267 	}
268 	error = SYSCTL_OUT(req, value, strlen(value));
269 	if (buf != NULL)
270 		free(buf, M_BUS);
271 	return (error);
272 }
273 
274 static void
275 device_sysctl_init(device_t dev)
276 {
277 	devclass_t dc = dev->devclass;
278 
279 	if (dev->sysctl_tree != NULL)
280 		return;
281 	devclass_sysctl_init(dc);
282 	sysctl_ctx_init(&dev->sysctl_ctx);
283 	dev->sysctl_tree = SYSCTL_ADD_NODE(&dev->sysctl_ctx,
284 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
285 	    dev->nameunit + strlen(dc->name),
286 	    CTLFLAG_RD, 0, "");
287 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
288 	    OID_AUTO, "%desc", CTLFLAG_RD,
289 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
290 	    "device description");
291 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
292 	    OID_AUTO, "%driver", CTLFLAG_RD,
293 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
294 	    "device driver name");
295 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
296 	    OID_AUTO, "%location", CTLFLAG_RD,
297 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
298 	    "device location relative to parent");
299 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
300 	    OID_AUTO, "%pnpinfo", CTLFLAG_RD,
301 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
302 	    "device identification");
303 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
304 	    OID_AUTO, "%parent", CTLFLAG_RD,
305 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
306 	    "parent device");
307 }
308 
309 static void
310 device_sysctl_update(device_t dev)
311 {
312 	devclass_t dc = dev->devclass;
313 
314 	if (dev->sysctl_tree == NULL)
315 		return;
316 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
317 }
318 
319 static void
320 device_sysctl_fini(device_t dev)
321 {
322 	if (dev->sysctl_tree == NULL)
323 		return;
324 	sysctl_ctx_free(&dev->sysctl_ctx);
325 	dev->sysctl_tree = NULL;
326 }
327 
328 /*
329  * /dev/devctl implementation
330  */
331 
332 /*
333  * This design allows only one reader for /dev/devctl.  This is not desirable
334  * in the long run, but will get a lot of hair out of this implementation.
335  * Maybe we should make this device a clonable device.
336  *
337  * Also note: we specifically do not attach a device to the device_t tree
338  * to avoid potential chicken and egg problems.  One could argue that all
339  * of this belongs to the root node.  One could also further argue that the
340  * sysctl interface that we have not might more properly be an ioctl
341  * interface, but at this stage of the game, I'm not inclined to rock that
342  * boat.
343  *
344  * I'm also not sure that the SIGIO support is done correctly or not, as
345  * I copied it from a driver that had SIGIO support that likely hasn't been
346  * tested since 3.4 or 2.2.8!
347  */
348 
349 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
350 static int devctl_disable = 0;
351 TUNABLE_INT("hw.bus.devctl_disable", &devctl_disable);
352 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RW, 0, 0,
353     sysctl_devctl_disable, "I", "devctl disable");
354 
355 static d_open_t		devopen;
356 static d_close_t	devclose;
357 static d_read_t		devread;
358 static d_ioctl_t	devioctl;
359 static d_poll_t		devpoll;
360 
361 static struct cdevsw dev_cdevsw = {
362 	.d_version =	D_VERSION,
363 	.d_flags =	D_NEEDGIANT,
364 	.d_open =	devopen,
365 	.d_close =	devclose,
366 	.d_read =	devread,
367 	.d_ioctl =	devioctl,
368 	.d_poll =	devpoll,
369 	.d_name =	"devctl",
370 };
371 
372 struct dev_event_info
373 {
374 	char *dei_data;
375 	TAILQ_ENTRY(dev_event_info) dei_link;
376 };
377 
378 TAILQ_HEAD(devq, dev_event_info);
379 
380 static struct dev_softc
381 {
382 	int	inuse;
383 	int	nonblock;
384 	struct mtx mtx;
385 	struct cv cv;
386 	struct selinfo sel;
387 	struct devq devq;
388 	struct proc *async_proc;
389 } devsoftc;
390 
391 static struct cdev *devctl_dev;
392 
393 static void
394 devinit(void)
395 {
396 	devctl_dev = make_dev(&dev_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
397 	    "devctl");
398 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
399 	cv_init(&devsoftc.cv, "dev cv");
400 	TAILQ_INIT(&devsoftc.devq);
401 }
402 
403 static int
404 devopen(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
405 {
406 	if (devsoftc.inuse)
407 		return (EBUSY);
408 	/* move to init */
409 	devsoftc.inuse = 1;
410 	devsoftc.nonblock = 0;
411 	devsoftc.async_proc = NULL;
412 	return (0);
413 }
414 
415 static int
416 devclose(struct cdev *dev, int fflag, int devtype, d_thread_t *td)
417 {
418 	devsoftc.inuse = 0;
419 	mtx_lock(&devsoftc.mtx);
420 	cv_broadcast(&devsoftc.cv);
421 	mtx_unlock(&devsoftc.mtx);
422 
423 	return (0);
424 }
425 
426 /*
427  * The read channel for this device is used to report changes to
428  * userland in realtime.  We are required to free the data as well as
429  * the n1 object because we allocate them separately.  Also note that
430  * we return one record at a time.  If you try to read this device a
431  * character at a time, you will lose the rest of the data.  Listening
432  * programs are expected to cope.
433  */
434 static int
435 devread(struct cdev *dev, struct uio *uio, int ioflag)
436 {
437 	struct dev_event_info *n1;
438 	int rv;
439 
440 	mtx_lock(&devsoftc.mtx);
441 	while (TAILQ_EMPTY(&devsoftc.devq)) {
442 		if (devsoftc.nonblock) {
443 			mtx_unlock(&devsoftc.mtx);
444 			return (EAGAIN);
445 		}
446 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
447 		if (rv) {
448 			/*
449 			 * Need to translate ERESTART to EINTR here? -- jake
450 			 */
451 			mtx_unlock(&devsoftc.mtx);
452 			return (rv);
453 		}
454 	}
455 	n1 = TAILQ_FIRST(&devsoftc.devq);
456 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
457 	mtx_unlock(&devsoftc.mtx);
458 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
459 	free(n1->dei_data, M_BUS);
460 	free(n1, M_BUS);
461 	return (rv);
462 }
463 
464 static	int
465 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, d_thread_t *td)
466 {
467 	switch (cmd) {
468 
469 	case FIONBIO:
470 		if (*(int*)data)
471 			devsoftc.nonblock = 1;
472 		else
473 			devsoftc.nonblock = 0;
474 		return (0);
475 	case FIOASYNC:
476 		if (*(int*)data)
477 			devsoftc.async_proc = td->td_proc;
478 		else
479 			devsoftc.async_proc = NULL;
480 		return (0);
481 
482 		/* (un)Support for other fcntl() calls. */
483 	case FIOCLEX:
484 	case FIONCLEX:
485 	case FIONREAD:
486 	case FIOSETOWN:
487 	case FIOGETOWN:
488 	default:
489 		break;
490 	}
491 	return (ENOTTY);
492 }
493 
494 static	int
495 devpoll(struct cdev *dev, int events, d_thread_t *td)
496 {
497 	int	revents = 0;
498 
499 	mtx_lock(&devsoftc.mtx);
500 	if (events & (POLLIN | POLLRDNORM)) {
501 		if (!TAILQ_EMPTY(&devsoftc.devq))
502 			revents = events & (POLLIN | POLLRDNORM);
503 		else
504 			selrecord(td, &devsoftc.sel);
505 	}
506 	mtx_unlock(&devsoftc.mtx);
507 
508 	return (revents);
509 }
510 
511 /**
512  * @brief Return whether the userland process is running
513  */
514 boolean_t
515 devctl_process_running(void)
516 {
517 	return (devsoftc.async_proc != NULL);
518 }
519 
520 /**
521  * @brief Queue data to be read from the devctl device
522  *
523  * Generic interface to queue data to the devctl device.  It is
524  * assumed that @p data is properly formatted.  It is further assumed
525  * that @p data is allocated using the M_BUS malloc type.
526  */
527 void
528 devctl_queue_data(char *data)
529 {
530 	struct dev_event_info *n1 = NULL;
531 	struct proc *p;
532 
533 	n1 = malloc(sizeof(*n1), M_BUS, M_NOWAIT);
534 	if (n1 == NULL)
535 		return;
536 	n1->dei_data = data;
537 	mtx_lock(&devsoftc.mtx);
538 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
539 	cv_broadcast(&devsoftc.cv);
540 	mtx_unlock(&devsoftc.mtx);
541 	selwakeup(&devsoftc.sel);
542 	p = devsoftc.async_proc;
543 	if (p != NULL) {
544 		PROC_LOCK(p);
545 		psignal(p, SIGIO);
546 		PROC_UNLOCK(p);
547 	}
548 }
549 
550 /**
551  * @brief Send a 'notification' to userland, using standard ways
552  */
553 void
554 devctl_notify(const char *system, const char *subsystem, const char *type,
555     const char *data)
556 {
557 	int len = 0;
558 	char *msg;
559 
560 	if (system == NULL)
561 		return;		/* BOGUS!  Must specify system. */
562 	if (subsystem == NULL)
563 		return;		/* BOGUS!  Must specify subsystem. */
564 	if (type == NULL)
565 		return;		/* BOGUS!  Must specify type. */
566 	len += strlen(" system=") + strlen(system);
567 	len += strlen(" subsystem=") + strlen(subsystem);
568 	len += strlen(" type=") + strlen(type);
569 	/* add in the data message plus newline. */
570 	if (data != NULL)
571 		len += strlen(data);
572 	len += 3;	/* '!', '\n', and NUL */
573 	msg = malloc(len, M_BUS, M_NOWAIT);
574 	if (msg == NULL)
575 		return;		/* Drop it on the floor */
576 	if (data != NULL)
577 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
578 		    system, subsystem, type, data);
579 	else
580 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
581 		    system, subsystem, type);
582 	devctl_queue_data(msg);
583 }
584 
585 /*
586  * Common routine that tries to make sending messages as easy as possible.
587  * We allocate memory for the data, copy strings into that, but do not
588  * free it unless there's an error.  The dequeue part of the driver should
589  * free the data.  We don't send data when the device is disabled.  We do
590  * send data, even when we have no listeners, because we wish to avoid
591  * races relating to startup and restart of listening applications.
592  *
593  * devaddq is designed to string together the type of event, with the
594  * object of that event, plus the plug and play info and location info
595  * for that event.  This is likely most useful for devices, but less
596  * useful for other consumers of this interface.  Those should use
597  * the devctl_queue_data() interface instead.
598  */
599 static void
600 devaddq(const char *type, const char *what, device_t dev)
601 {
602 	char *data = NULL;
603 	char *loc = NULL;
604 	char *pnp = NULL;
605 	const char *parstr;
606 
607 	if (devctl_disable)
608 		return;
609 	data = malloc(1024, M_BUS, M_NOWAIT);
610 	if (data == NULL)
611 		goto bad;
612 
613 	/* get the bus specific location of this device */
614 	loc = malloc(1024, M_BUS, M_NOWAIT);
615 	if (loc == NULL)
616 		goto bad;
617 	*loc = '\0';
618 	bus_child_location_str(dev, loc, 1024);
619 
620 	/* Get the bus specific pnp info of this device */
621 	pnp = malloc(1024, M_BUS, M_NOWAIT);
622 	if (pnp == NULL)
623 		goto bad;
624 	*pnp = '\0';
625 	bus_child_pnpinfo_str(dev, pnp, 1024);
626 
627 	/* Get the parent of this device, or / if high enough in the tree. */
628 	if (device_get_parent(dev) == NULL)
629 		parstr = ".";	/* Or '/' ? */
630 	else
631 		parstr = device_get_nameunit(device_get_parent(dev));
632 	/* String it all together. */
633 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
634 	  parstr);
635 	free(loc, M_BUS);
636 	free(pnp, M_BUS);
637 	devctl_queue_data(data);
638 	return;
639 bad:
640 	free(pnp, M_BUS);
641 	free(loc, M_BUS);
642 	free(data, M_BUS);
643 	return;
644 }
645 
646 /*
647  * A device was added to the tree.  We are called just after it successfully
648  * attaches (that is, probe and attach success for this device).  No call
649  * is made if a device is merely parented into the tree.  See devnomatch
650  * if probe fails.  If attach fails, no notification is sent (but maybe
651  * we should have a different message for this).
652  */
653 static void
654 devadded(device_t dev)
655 {
656 	char *pnp = NULL;
657 	char *tmp = NULL;
658 
659 	pnp = malloc(1024, M_BUS, M_NOWAIT);
660 	if (pnp == NULL)
661 		goto fail;
662 	tmp = malloc(1024, M_BUS, M_NOWAIT);
663 	if (tmp == NULL)
664 		goto fail;
665 	*pnp = '\0';
666 	bus_child_pnpinfo_str(dev, pnp, 1024);
667 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
668 	devaddq("+", tmp, dev);
669 fail:
670 	if (pnp != NULL)
671 		free(pnp, M_BUS);
672 	if (tmp != NULL)
673 		free(tmp, M_BUS);
674 	return;
675 }
676 
677 /*
678  * A device was removed from the tree.  We are called just before this
679  * happens.
680  */
681 static void
682 devremoved(device_t dev)
683 {
684 	char *pnp = NULL;
685 	char *tmp = NULL;
686 
687 	pnp = malloc(1024, M_BUS, M_NOWAIT);
688 	if (pnp == NULL)
689 		goto fail;
690 	tmp = malloc(1024, M_BUS, M_NOWAIT);
691 	if (tmp == NULL)
692 		goto fail;
693 	*pnp = '\0';
694 	bus_child_pnpinfo_str(dev, pnp, 1024);
695 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
696 	devaddq("-", tmp, dev);
697 fail:
698 	if (pnp != NULL)
699 		free(pnp, M_BUS);
700 	if (tmp != NULL)
701 		free(tmp, M_BUS);
702 	return;
703 }
704 
705 /*
706  * Called when there's no match for this device.  This is only called
707  * the first time that no match happens, so we don't keep getitng this
708  * message.  Should that prove to be undesirable, we can change it.
709  * This is called when all drivers that can attach to a given bus
710  * decline to accept this device.  Other errrors may not be detected.
711  */
712 static void
713 devnomatch(device_t dev)
714 {
715 	devaddq("?", "", dev);
716 }
717 
718 static int
719 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
720 {
721 	struct dev_event_info *n1;
722 	int dis, error;
723 
724 	dis = devctl_disable;
725 	error = sysctl_handle_int(oidp, &dis, 0, req);
726 	if (error || !req->newptr)
727 		return (error);
728 	mtx_lock(&devsoftc.mtx);
729 	devctl_disable = dis;
730 	if (dis) {
731 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
732 			n1 = TAILQ_FIRST(&devsoftc.devq);
733 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
734 			free(n1->dei_data, M_BUS);
735 			free(n1, M_BUS);
736 		}
737 	}
738 	mtx_unlock(&devsoftc.mtx);
739 	return (0);
740 }
741 
742 /* End of /dev/devctl code */
743 
744 TAILQ_HEAD(,device)	bus_data_devices;
745 static int bus_data_generation = 1;
746 
747 kobj_method_t null_methods[] = {
748 	{ 0, 0 }
749 };
750 
751 DEFINE_CLASS(null, null_methods, 0);
752 
753 /*
754  * Devclass implementation
755  */
756 
757 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
758 
759 
760 /**
761  * @internal
762  * @brief Find or create a device class
763  *
764  * If a device class with the name @p classname exists, return it,
765  * otherwise if @p create is non-zero create and return a new device
766  * class.
767  *
768  * If @p parentname is non-NULL, the parent of the devclass is set to
769  * the devclass of that name.
770  *
771  * @param classname	the devclass name to find or create
772  * @param parentname	the parent devclass name or @c NULL
773  * @param create	non-zero to create a devclass
774  */
775 static devclass_t
776 devclass_find_internal(const char *classname, const char *parentname,
777 		       int create)
778 {
779 	devclass_t dc;
780 
781 	PDEBUG(("looking for %s", classname));
782 	if (!classname)
783 		return (NULL);
784 
785 	TAILQ_FOREACH(dc, &devclasses, link) {
786 		if (!strcmp(dc->name, classname))
787 			break;
788 	}
789 
790 	if (create && !dc) {
791 		PDEBUG(("creating %s", classname));
792 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
793 		    M_BUS, M_NOWAIT|M_ZERO);
794 		if (!dc)
795 			return (NULL);
796 		dc->parent = NULL;
797 		dc->name = (char*) (dc + 1);
798 		strcpy(dc->name, classname);
799 		TAILQ_INIT(&dc->drivers);
800 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
801 
802 		bus_data_generation_update();
803 	}
804 
805 	/*
806 	 * If a parent class is specified, then set that as our parent so
807 	 * that this devclass will support drivers for the parent class as
808 	 * well.  If the parent class has the same name don't do this though
809 	 * as it creates a cycle that can trigger an infinite loop in
810 	 * device_probe_child() if a device exists for which there is no
811 	 * suitable driver.
812 	 */
813 	if (parentname && dc && !dc->parent &&
814 	    strcmp(classname, parentname) != 0) {
815 		dc->parent = devclass_find_internal(parentname, NULL, FALSE);
816 	}
817 
818 	return (dc);
819 }
820 
821 /**
822  * @brief Create a device class
823  *
824  * If a device class with the name @p classname exists, return it,
825  * otherwise create and return a new device class.
826  *
827  * @param classname	the devclass name to find or create
828  */
829 devclass_t
830 devclass_create(const char *classname)
831 {
832 	return (devclass_find_internal(classname, NULL, TRUE));
833 }
834 
835 /**
836  * @brief Find a device class
837  *
838  * If a device class with the name @p classname exists, return it,
839  * otherwise return @c NULL.
840  *
841  * @param classname	the devclass name to find
842  */
843 devclass_t
844 devclass_find(const char *classname)
845 {
846 	return (devclass_find_internal(classname, NULL, FALSE));
847 }
848 
849 /**
850  * @brief Add a device driver to a device class
851  *
852  * Add a device driver to a devclass. This is normally called
853  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
854  * all devices in the devclass will be called to allow them to attempt
855  * to re-probe any unmatched children.
856  *
857  * @param dc		the devclass to edit
858  * @param driver	the driver to register
859  */
860 int
861 devclass_add_driver(devclass_t dc, driver_t *driver)
862 {
863 	driverlink_t dl;
864 	int i;
865 
866 	PDEBUG(("%s", DRIVERNAME(driver)));
867 
868 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
869 	if (!dl)
870 		return (ENOMEM);
871 
872 	/*
873 	 * Compile the driver's methods. Also increase the reference count
874 	 * so that the class doesn't get freed when the last instance
875 	 * goes. This means we can safely use static methods and avoids a
876 	 * double-free in devclass_delete_driver.
877 	 */
878 	kobj_class_compile((kobj_class_t) driver);
879 
880 	/*
881 	 * Make sure the devclass which the driver is implementing exists.
882 	 */
883 	devclass_find_internal(driver->name, NULL, TRUE);
884 
885 	dl->driver = driver;
886 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
887 	driver->refs++;		/* XXX: kobj_mtx */
888 
889 	/*
890 	 * Call BUS_DRIVER_ADDED for any existing busses in this class.
891 	 */
892 	for (i = 0; i < dc->maxunit; i++)
893 		if (dc->devices[i])
894 			BUS_DRIVER_ADDED(dc->devices[i], driver);
895 
896 	bus_data_generation_update();
897 	return (0);
898 }
899 
900 /**
901  * @brief Delete a device driver from a device class
902  *
903  * Delete a device driver from a devclass. This is normally called
904  * automatically by DRIVER_MODULE().
905  *
906  * If the driver is currently attached to any devices,
907  * devclass_delete_driver() will first attempt to detach from each
908  * device. If one of the detach calls fails, the driver will not be
909  * deleted.
910  *
911  * @param dc		the devclass to edit
912  * @param driver	the driver to unregister
913  */
914 int
915 devclass_delete_driver(devclass_t busclass, driver_t *driver)
916 {
917 	devclass_t dc = devclass_find(driver->name);
918 	driverlink_t dl;
919 	device_t dev;
920 	int i;
921 	int error;
922 
923 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
924 
925 	if (!dc)
926 		return (0);
927 
928 	/*
929 	 * Find the link structure in the bus' list of drivers.
930 	 */
931 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
932 		if (dl->driver == driver)
933 			break;
934 	}
935 
936 	if (!dl) {
937 		PDEBUG(("%s not found in %s list", driver->name,
938 		    busclass->name));
939 		return (ENOENT);
940 	}
941 
942 	/*
943 	 * Disassociate from any devices.  We iterate through all the
944 	 * devices in the devclass of the driver and detach any which are
945 	 * using the driver and which have a parent in the devclass which
946 	 * we are deleting from.
947 	 *
948 	 * Note that since a driver can be in multiple devclasses, we
949 	 * should not detach devices which are not children of devices in
950 	 * the affected devclass.
951 	 */
952 	for (i = 0; i < dc->maxunit; i++) {
953 		if (dc->devices[i]) {
954 			dev = dc->devices[i];
955 			if (dev->driver == driver && dev->parent &&
956 			    dev->parent->devclass == busclass) {
957 				if ((error = device_detach(dev)) != 0)
958 					return (error);
959 				device_set_driver(dev, NULL);
960 			}
961 		}
962 	}
963 
964 	TAILQ_REMOVE(&busclass->drivers, dl, link);
965 	free(dl, M_BUS);
966 
967 	/* XXX: kobj_mtx */
968 	driver->refs--;
969 	if (driver->refs == 0)
970 		kobj_class_free((kobj_class_t) driver);
971 
972 	bus_data_generation_update();
973 	return (0);
974 }
975 
976 /**
977  * @brief Quiesces a set of device drivers from a device class
978  *
979  * Quiesce a device driver from a devclass. This is normally called
980  * automatically by DRIVER_MODULE().
981  *
982  * If the driver is currently attached to any devices,
983  * devclass_quiesece_driver() will first attempt to quiesce each
984  * device.
985  *
986  * @param dc		the devclass to edit
987  * @param driver	the driver to unregister
988  */
989 int
990 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
991 {
992 	devclass_t dc = devclass_find(driver->name);
993 	driverlink_t dl;
994 	device_t dev;
995 	int i;
996 	int error;
997 
998 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
999 
1000 	if (!dc)
1001 		return (0);
1002 
1003 	/*
1004 	 * Find the link structure in the bus' list of drivers.
1005 	 */
1006 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1007 		if (dl->driver == driver)
1008 			break;
1009 	}
1010 
1011 	if (!dl) {
1012 		PDEBUG(("%s not found in %s list", driver->name,
1013 		    busclass->name));
1014 		return (ENOENT);
1015 	}
1016 
1017 	/*
1018 	 * Quiesce all devices.  We iterate through all the devices in
1019 	 * the devclass of the driver and quiesce any which are using
1020 	 * the driver and which have a parent in the devclass which we
1021 	 * are quiescing.
1022 	 *
1023 	 * Note that since a driver can be in multiple devclasses, we
1024 	 * should not quiesce devices which are not children of
1025 	 * devices in the affected devclass.
1026 	 */
1027 	for (i = 0; i < dc->maxunit; i++) {
1028 		if (dc->devices[i]) {
1029 			dev = dc->devices[i];
1030 			if (dev->driver == driver && dev->parent &&
1031 			    dev->parent->devclass == busclass) {
1032 				if ((error = device_quiesce(dev)) != 0)
1033 					return (error);
1034 			}
1035 		}
1036 	}
1037 
1038 	return (0);
1039 }
1040 
1041 /**
1042  * @internal
1043  */
1044 static driverlink_t
1045 devclass_find_driver_internal(devclass_t dc, const char *classname)
1046 {
1047 	driverlink_t dl;
1048 
1049 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1050 
1051 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1052 		if (!strcmp(dl->driver->name, classname))
1053 			return (dl);
1054 	}
1055 
1056 	PDEBUG(("not found"));
1057 	return (NULL);
1058 }
1059 
1060 /**
1061  * @brief Search a devclass for a driver
1062  *
1063  * This function searches the devclass's list of drivers and returns
1064  * the first driver whose name is @p classname or @c NULL if there is
1065  * no driver of that name.
1066  *
1067  * @param dc		the devclass to search
1068  * @param classname	the driver name to search for
1069  */
1070 kobj_class_t
1071 devclass_find_driver(devclass_t dc, const char *classname)
1072 {
1073 	driverlink_t dl;
1074 
1075 	dl = devclass_find_driver_internal(dc, classname);
1076 	if (dl)
1077 		return (dl->driver);
1078 	return (NULL);
1079 }
1080 
1081 /**
1082  * @brief Return the name of the devclass
1083  */
1084 const char *
1085 devclass_get_name(devclass_t dc)
1086 {
1087 	return (dc->name);
1088 }
1089 
1090 /**
1091  * @brief Find a device given a unit number
1092  *
1093  * @param dc		the devclass to search
1094  * @param unit		the unit number to search for
1095  *
1096  * @returns		the device with the given unit number or @c
1097  *			NULL if there is no such device
1098  */
1099 device_t
1100 devclass_get_device(devclass_t dc, int unit)
1101 {
1102 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1103 		return (NULL);
1104 	return (dc->devices[unit]);
1105 }
1106 
1107 /**
1108  * @brief Find the softc field of a device given a unit number
1109  *
1110  * @param dc		the devclass to search
1111  * @param unit		the unit number to search for
1112  *
1113  * @returns		the softc field of the device with the given
1114  *			unit number or @c NULL if there is no such
1115  *			device
1116  */
1117 void *
1118 devclass_get_softc(devclass_t dc, int unit)
1119 {
1120 	device_t dev;
1121 
1122 	dev = devclass_get_device(dc, unit);
1123 	if (!dev)
1124 		return (NULL);
1125 
1126 	return (device_get_softc(dev));
1127 }
1128 
1129 /**
1130  * @brief Get a list of devices in the devclass
1131  *
1132  * An array containing a list of all the devices in the given devclass
1133  * is allocated and returned in @p *devlistp. The number of devices
1134  * in the array is returned in @p *devcountp. The caller should free
1135  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1136  *
1137  * @param dc		the devclass to examine
1138  * @param devlistp	points at location for array pointer return
1139  *			value
1140  * @param devcountp	points at location for array size return value
1141  *
1142  * @retval 0		success
1143  * @retval ENOMEM	the array allocation failed
1144  */
1145 int
1146 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1147 {
1148 	int count, i;
1149 	device_t *list;
1150 
1151 	count = devclass_get_count(dc);
1152 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1153 	if (!list)
1154 		return (ENOMEM);
1155 
1156 	count = 0;
1157 	for (i = 0; i < dc->maxunit; i++) {
1158 		if (dc->devices[i]) {
1159 			list[count] = dc->devices[i];
1160 			count++;
1161 		}
1162 	}
1163 
1164 	*devlistp = list;
1165 	*devcountp = count;
1166 
1167 	return (0);
1168 }
1169 
1170 /**
1171  * @brief Get a list of drivers in the devclass
1172  *
1173  * An array containing a list of pointers to all the drivers in the
1174  * given devclass is allocated and returned in @p *listp.  The number
1175  * of drivers in the array is returned in @p *countp. The caller should
1176  * free the array using @c free(p, M_TEMP).
1177  *
1178  * @param dc		the devclass to examine
1179  * @param listp		gives location for array pointer return value
1180  * @param countp	gives location for number of array elements
1181  *			return value
1182  *
1183  * @retval 0		success
1184  * @retval ENOMEM	the array allocation failed
1185  */
1186 int
1187 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1188 {
1189 	driverlink_t dl;
1190 	driver_t **list;
1191 	int count;
1192 
1193 	count = 0;
1194 	TAILQ_FOREACH(dl, &dc->drivers, link)
1195 		count++;
1196 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1197 	if (list == NULL)
1198 		return (ENOMEM);
1199 
1200 	count = 0;
1201 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1202 		list[count] = dl->driver;
1203 		count++;
1204 	}
1205 	*listp = list;
1206 	*countp = count;
1207 
1208 	return (0);
1209 }
1210 
1211 /**
1212  * @brief Get the number of devices in a devclass
1213  *
1214  * @param dc		the devclass to examine
1215  */
1216 int
1217 devclass_get_count(devclass_t dc)
1218 {
1219 	int count, i;
1220 
1221 	count = 0;
1222 	for (i = 0; i < dc->maxunit; i++)
1223 		if (dc->devices[i])
1224 			count++;
1225 	return (count);
1226 }
1227 
1228 /**
1229  * @brief Get the maximum unit number used in a devclass
1230  *
1231  * Note that this is one greater than the highest currently-allocated
1232  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1233  * that not even the devclass has been allocated yet.
1234  *
1235  * @param dc		the devclass to examine
1236  */
1237 int
1238 devclass_get_maxunit(devclass_t dc)
1239 {
1240 	if (dc == NULL)
1241 		return (-1);
1242 	return (dc->maxunit);
1243 }
1244 
1245 /**
1246  * @brief Find a free unit number in a devclass
1247  *
1248  * This function searches for the first unused unit number greater
1249  * that or equal to @p unit.
1250  *
1251  * @param dc		the devclass to examine
1252  * @param unit		the first unit number to check
1253  */
1254 int
1255 devclass_find_free_unit(devclass_t dc, int unit)
1256 {
1257 	if (dc == NULL)
1258 		return (unit);
1259 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1260 		unit++;
1261 	return (unit);
1262 }
1263 
1264 /**
1265  * @brief Set the parent of a devclass
1266  *
1267  * The parent class is normally initialised automatically by
1268  * DRIVER_MODULE().
1269  *
1270  * @param dc		the devclass to edit
1271  * @param pdc		the new parent devclass
1272  */
1273 void
1274 devclass_set_parent(devclass_t dc, devclass_t pdc)
1275 {
1276 	dc->parent = pdc;
1277 }
1278 
1279 /**
1280  * @brief Get the parent of a devclass
1281  *
1282  * @param dc		the devclass to examine
1283  */
1284 devclass_t
1285 devclass_get_parent(devclass_t dc)
1286 {
1287 	return (dc->parent);
1288 }
1289 
1290 struct sysctl_ctx_list *
1291 devclass_get_sysctl_ctx(devclass_t dc)
1292 {
1293 	return (&dc->sysctl_ctx);
1294 }
1295 
1296 struct sysctl_oid *
1297 devclass_get_sysctl_tree(devclass_t dc)
1298 {
1299 	return (dc->sysctl_tree);
1300 }
1301 
1302 /**
1303  * @internal
1304  * @brief Allocate a unit number
1305  *
1306  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1307  * will do). The allocated unit number is returned in @p *unitp.
1308 
1309  * @param dc		the devclass to allocate from
1310  * @param unitp		points at the location for the allocated unit
1311  *			number
1312  *
1313  * @retval 0		success
1314  * @retval EEXIST	the requested unit number is already allocated
1315  * @retval ENOMEM	memory allocation failure
1316  */
1317 static int
1318 devclass_alloc_unit(devclass_t dc, int *unitp)
1319 {
1320 	int unit = *unitp;
1321 
1322 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1323 
1324 	/* If we were given a wired unit number, check for existing device */
1325 	/* XXX imp XXX */
1326 	if (unit != -1) {
1327 		if (unit >= 0 && unit < dc->maxunit &&
1328 		    dc->devices[unit] != NULL) {
1329 			if (bootverbose)
1330 				printf("%s: %s%d already exists; skipping it\n",
1331 				    dc->name, dc->name, *unitp);
1332 			return (EEXIST);
1333 		}
1334 	} else {
1335 		/* Unwired device, find the next available slot for it */
1336 		unit = 0;
1337 		while (unit < dc->maxunit && dc->devices[unit] != NULL)
1338 			unit++;
1339 	}
1340 
1341 	/*
1342 	 * We've selected a unit beyond the length of the table, so let's
1343 	 * extend the table to make room for all units up to and including
1344 	 * this one.
1345 	 */
1346 	if (unit >= dc->maxunit) {
1347 		device_t *newlist;
1348 		int newsize;
1349 
1350 		newsize = roundup((unit + 1), MINALLOCSIZE / sizeof(device_t));
1351 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1352 		if (!newlist)
1353 			return (ENOMEM);
1354 		bcopy(dc->devices, newlist, sizeof(device_t) * dc->maxunit);
1355 		bzero(newlist + dc->maxunit,
1356 		    sizeof(device_t) * (newsize - dc->maxunit));
1357 		if (dc->devices)
1358 			free(dc->devices, M_BUS);
1359 		dc->devices = newlist;
1360 		dc->maxunit = newsize;
1361 	}
1362 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1363 
1364 	*unitp = unit;
1365 	return (0);
1366 }
1367 
1368 /**
1369  * @internal
1370  * @brief Add a device to a devclass
1371  *
1372  * A unit number is allocated for the device (using the device's
1373  * preferred unit number if any) and the device is registered in the
1374  * devclass. This allows the device to be looked up by its unit
1375  * number, e.g. by decoding a dev_t minor number.
1376  *
1377  * @param dc		the devclass to add to
1378  * @param dev		the device to add
1379  *
1380  * @retval 0		success
1381  * @retval EEXIST	the requested unit number is already allocated
1382  * @retval ENOMEM	memory allocation failure
1383  */
1384 static int
1385 devclass_add_device(devclass_t dc, device_t dev)
1386 {
1387 	int buflen, error;
1388 
1389 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1390 
1391 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, dev->unit);
1392 	if (buflen < 0)
1393 		return (ENOMEM);
1394 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1395 	if (!dev->nameunit)
1396 		return (ENOMEM);
1397 
1398 	if ((error = devclass_alloc_unit(dc, &dev->unit)) != 0) {
1399 		free(dev->nameunit, M_BUS);
1400 		dev->nameunit = NULL;
1401 		return (error);
1402 	}
1403 	dc->devices[dev->unit] = dev;
1404 	dev->devclass = dc;
1405 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1406 
1407 	return (0);
1408 }
1409 
1410 /**
1411  * @internal
1412  * @brief Delete a device from a devclass
1413  *
1414  * The device is removed from the devclass's device list and its unit
1415  * number is freed.
1416 
1417  * @param dc		the devclass to delete from
1418  * @param dev		the device to delete
1419  *
1420  * @retval 0		success
1421  */
1422 static int
1423 devclass_delete_device(devclass_t dc, device_t dev)
1424 {
1425 	if (!dc || !dev)
1426 		return (0);
1427 
1428 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1429 
1430 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1431 		panic("devclass_delete_device: inconsistent device class");
1432 	dc->devices[dev->unit] = NULL;
1433 	if (dev->flags & DF_WILDCARD)
1434 		dev->unit = -1;
1435 	dev->devclass = NULL;
1436 	free(dev->nameunit, M_BUS);
1437 	dev->nameunit = NULL;
1438 
1439 	return (0);
1440 }
1441 
1442 /**
1443  * @internal
1444  * @brief Make a new device and add it as a child of @p parent
1445  *
1446  * @param parent	the parent of the new device
1447  * @param name		the devclass name of the new device or @c NULL
1448  *			to leave the devclass unspecified
1449  * @parem unit		the unit number of the new device of @c -1 to
1450  *			leave the unit number unspecified
1451  *
1452  * @returns the new device
1453  */
1454 static device_t
1455 make_device(device_t parent, const char *name, int unit)
1456 {
1457 	device_t dev;
1458 	devclass_t dc;
1459 
1460 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1461 
1462 	if (name) {
1463 		dc = devclass_find_internal(name, NULL, TRUE);
1464 		if (!dc) {
1465 			printf("make_device: can't find device class %s\n",
1466 			    name);
1467 			return (NULL);
1468 		}
1469 	} else {
1470 		dc = NULL;
1471 	}
1472 
1473 	dev = malloc(sizeof(struct device), M_BUS, M_NOWAIT|M_ZERO);
1474 	if (!dev)
1475 		return (NULL);
1476 
1477 	dev->parent = parent;
1478 	TAILQ_INIT(&dev->children);
1479 	kobj_init((kobj_t) dev, &null_class);
1480 	dev->driver = NULL;
1481 	dev->devclass = NULL;
1482 	dev->unit = unit;
1483 	dev->nameunit = NULL;
1484 	dev->desc = NULL;
1485 	dev->busy = 0;
1486 	dev->devflags = 0;
1487 	dev->flags = DF_ENABLED;
1488 	dev->order = 0;
1489 	if (unit == -1)
1490 		dev->flags |= DF_WILDCARD;
1491 	if (name) {
1492 		dev->flags |= DF_FIXEDCLASS;
1493 		if (devclass_add_device(dc, dev)) {
1494 			kobj_delete((kobj_t) dev, M_BUS);
1495 			return (NULL);
1496 		}
1497 	}
1498 	dev->ivars = NULL;
1499 	dev->softc = NULL;
1500 
1501 	dev->state = DS_NOTPRESENT;
1502 
1503 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1504 	bus_data_generation_update();
1505 
1506 	return (dev);
1507 }
1508 
1509 /**
1510  * @internal
1511  * @brief Print a description of a device.
1512  */
1513 static int
1514 device_print_child(device_t dev, device_t child)
1515 {
1516 	int retval = 0;
1517 
1518 	if (device_is_alive(child))
1519 		retval += BUS_PRINT_CHILD(dev, child);
1520 	else
1521 		retval += device_printf(child, " not found\n");
1522 
1523 	return (retval);
1524 }
1525 
1526 /**
1527  * @brief Create a new device
1528  *
1529  * This creates a new device and adds it as a child of an existing
1530  * parent device. The new device will be added after the last existing
1531  * child with order zero.
1532  *
1533  * @param dev		the device which will be the parent of the
1534  *			new child device
1535  * @param name		devclass name for new device or @c NULL if not
1536  *			specified
1537  * @param unit		unit number for new device or @c -1 if not
1538  *			specified
1539  *
1540  * @returns		the new device
1541  */
1542 device_t
1543 device_add_child(device_t dev, const char *name, int unit)
1544 {
1545 	return (device_add_child_ordered(dev, 0, name, unit));
1546 }
1547 
1548 /**
1549  * @brief Create a new device
1550  *
1551  * This creates a new device and adds it as a child of an existing
1552  * parent device. The new device will be added after the last existing
1553  * child with the same order.
1554  *
1555  * @param dev		the device which will be the parent of the
1556  *			new child device
1557  * @param order		a value which is used to partially sort the
1558  *			children of @p dev - devices created using
1559  *			lower values of @p order appear first in @p
1560  *			dev's list of children
1561  * @param name		devclass name for new device or @c NULL if not
1562  *			specified
1563  * @param unit		unit number for new device or @c -1 if not
1564  *			specified
1565  *
1566  * @returns		the new device
1567  */
1568 device_t
1569 device_add_child_ordered(device_t dev, int order, const char *name, int unit)
1570 {
1571 	device_t child;
1572 	device_t place;
1573 
1574 	PDEBUG(("%s at %s with order %d as unit %d",
1575 	    name, DEVICENAME(dev), order, unit));
1576 
1577 	child = make_device(dev, name, unit);
1578 	if (child == NULL)
1579 		return (child);
1580 	child->order = order;
1581 
1582 	TAILQ_FOREACH(place, &dev->children, link) {
1583 		if (place->order > order)
1584 			break;
1585 	}
1586 
1587 	if (place) {
1588 		/*
1589 		 * The device 'place' is the first device whose order is
1590 		 * greater than the new child.
1591 		 */
1592 		TAILQ_INSERT_BEFORE(place, child, link);
1593 	} else {
1594 		/*
1595 		 * The new child's order is greater or equal to the order of
1596 		 * any existing device. Add the child to the tail of the list.
1597 		 */
1598 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1599 	}
1600 
1601 	bus_data_generation_update();
1602 	return (child);
1603 }
1604 
1605 /**
1606  * @brief Delete a device
1607  *
1608  * This function deletes a device along with all of its children. If
1609  * the device currently has a driver attached to it, the device is
1610  * detached first using device_detach().
1611  *
1612  * @param dev		the parent device
1613  * @param child		the device to delete
1614  *
1615  * @retval 0		success
1616  * @retval non-zero	a unit error code describing the error
1617  */
1618 int
1619 device_delete_child(device_t dev, device_t child)
1620 {
1621 	int error;
1622 	device_t grandchild;
1623 
1624 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1625 
1626 	/* remove children first */
1627 	while ( (grandchild = TAILQ_FIRST(&child->children)) ) {
1628 		error = device_delete_child(child, grandchild);
1629 		if (error)
1630 			return (error);
1631 	}
1632 
1633 	if ((error = device_detach(child)) != 0)
1634 		return (error);
1635 	if (child->devclass)
1636 		devclass_delete_device(child->devclass, child);
1637 	TAILQ_REMOVE(&dev->children, child, link);
1638 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1639 	kobj_delete((kobj_t) child, M_BUS);
1640 
1641 	bus_data_generation_update();
1642 	return (0);
1643 }
1644 
1645 /**
1646  * @brief Find a device given a unit number
1647  *
1648  * This is similar to devclass_get_devices() but only searches for
1649  * devices which have @p dev as a parent.
1650  *
1651  * @param dev		the parent device to search
1652  * @param unit		the unit number to search for.  If the unit is -1,
1653  *			return the first child of @p dev which has name
1654  *			@p classname (that is, the one with the lowest unit.)
1655  *
1656  * @returns		the device with the given unit number or @c
1657  *			NULL if there is no such device
1658  */
1659 device_t
1660 device_find_child(device_t dev, const char *classname, int unit)
1661 {
1662 	devclass_t dc;
1663 	device_t child;
1664 
1665 	dc = devclass_find(classname);
1666 	if (!dc)
1667 		return (NULL);
1668 
1669 	if (unit != -1) {
1670 		child = devclass_get_device(dc, unit);
1671 		if (child && child->parent == dev)
1672 			return (child);
1673 	} else {
1674 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
1675 			child = devclass_get_device(dc, unit);
1676 			if (child && child->parent == dev)
1677 				return (child);
1678 		}
1679 	}
1680 	return (NULL);
1681 }
1682 
1683 /**
1684  * @internal
1685  */
1686 static driverlink_t
1687 first_matching_driver(devclass_t dc, device_t dev)
1688 {
1689 	if (dev->devclass)
1690 		return (devclass_find_driver_internal(dc, dev->devclass->name));
1691 	return (TAILQ_FIRST(&dc->drivers));
1692 }
1693 
1694 /**
1695  * @internal
1696  */
1697 static driverlink_t
1698 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
1699 {
1700 	if (dev->devclass) {
1701 		driverlink_t dl;
1702 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
1703 			if (!strcmp(dev->devclass->name, dl->driver->name))
1704 				return (dl);
1705 		return (NULL);
1706 	}
1707 	return (TAILQ_NEXT(last, link));
1708 }
1709 
1710 /**
1711  * @internal
1712  */
1713 int
1714 device_probe_child(device_t dev, device_t child)
1715 {
1716 	devclass_t dc;
1717 	driverlink_t best = NULL;
1718 	driverlink_t dl;
1719 	int result, pri = 0;
1720 	int hasclass = (child->devclass != 0);
1721 
1722 	GIANT_REQUIRED;
1723 
1724 	dc = dev->devclass;
1725 	if (!dc)
1726 		panic("device_probe_child: parent device has no devclass");
1727 
1728 	/*
1729 	 * If the state is already probed, then return.  However, don't
1730 	 * return if we can rebid this object.
1731 	 */
1732 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
1733 		return (0);
1734 
1735 	for (; dc; dc = dc->parent) {
1736 		for (dl = first_matching_driver(dc, child);
1737 		     dl;
1738 		     dl = next_matching_driver(dc, child, dl)) {
1739 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
1740 			device_set_driver(child, dl->driver);
1741 			if (!hasclass)
1742 				device_set_devclass(child, dl->driver->name);
1743 
1744 			/* Fetch any flags for the device before probing. */
1745 			resource_int_value(dl->driver->name, child->unit,
1746 			    "flags", &child->devflags);
1747 
1748 			result = DEVICE_PROBE(child);
1749 
1750 			/* Reset flags and devclass before the next probe. */
1751 			child->devflags = 0;
1752 			if (!hasclass)
1753 				device_set_devclass(child, NULL);
1754 
1755 			/*
1756 			 * If the driver returns SUCCESS, there can be
1757 			 * no higher match for this device.
1758 			 */
1759 			if (result == 0) {
1760 				best = dl;
1761 				pri = 0;
1762 				break;
1763 			}
1764 
1765 			/*
1766 			 * The driver returned an error so it
1767 			 * certainly doesn't match.
1768 			 */
1769 			if (result > 0) {
1770 				device_set_driver(child, NULL);
1771 				continue;
1772 			}
1773 
1774 			/*
1775 			 * A priority lower than SUCCESS, remember the
1776 			 * best matching driver. Initialise the value
1777 			 * of pri for the first match.
1778 			 */
1779 			if (best == NULL || result > pri) {
1780 				best = dl;
1781 				pri = result;
1782 				continue;
1783 			}
1784 		}
1785 		/*
1786 		 * If we have an unambiguous match in this devclass,
1787 		 * don't look in the parent.
1788 		 */
1789 		if (best && pri == 0)
1790 			break;
1791 	}
1792 
1793 	/*
1794 	 * If we found a driver, change state and initialise the devclass.
1795 	 */
1796 	/* XXX What happens if we rebid and got no best? */
1797 	if (best) {
1798 		/*
1799 		 * If this device was atached, and we were asked to
1800 		 * rescan, and it is a different driver, then we have
1801 		 * to detach the old driver and reattach this new one.
1802 		 * Note, we don't have to check for DF_REBID here
1803 		 * because if the state is > DS_ALIVE, we know it must
1804 		 * be.
1805 		 *
1806 		 * This assumes that all DF_REBID drivers can have
1807 		 * their probe routine called at any time and that
1808 		 * they are idempotent as well as completely benign in
1809 		 * normal operations.
1810 		 *
1811 		 * We also have to make sure that the detach
1812 		 * succeeded, otherwise we fail the operation (or
1813 		 * maybe it should just fail silently?  I'm torn).
1814 		 */
1815 		if (child->state > DS_ALIVE && best->driver != child->driver)
1816 			if ((result = device_detach(dev)) != 0)
1817 				return (result);
1818 
1819 		/* Set the winning driver, devclass, and flags. */
1820 		if (!child->devclass)
1821 			device_set_devclass(child, best->driver->name);
1822 		device_set_driver(child, best->driver);
1823 		resource_int_value(best->driver->name, child->unit,
1824 		    "flags", &child->devflags);
1825 
1826 		if (pri < 0) {
1827 			/*
1828 			 * A bit bogus. Call the probe method again to make
1829 			 * sure that we have the right description.
1830 			 */
1831 			DEVICE_PROBE(child);
1832 #if 0
1833 			child->flags |= DF_REBID;
1834 #endif
1835 		} else
1836 			child->flags &= ~DF_REBID;
1837 		child->state = DS_ALIVE;
1838 
1839 		bus_data_generation_update();
1840 		return (0);
1841 	}
1842 
1843 	return (ENXIO);
1844 }
1845 
1846 /**
1847  * @brief Return the parent of a device
1848  */
1849 device_t
1850 device_get_parent(device_t dev)
1851 {
1852 	return (dev->parent);
1853 }
1854 
1855 /**
1856  * @brief Get a list of children of a device
1857  *
1858  * An array containing a list of all the children of the given device
1859  * is allocated and returned in @p *devlistp. The number of devices
1860  * in the array is returned in @p *devcountp. The caller should free
1861  * the array using @c free(p, M_TEMP).
1862  *
1863  * @param dev		the device to examine
1864  * @param devlistp	points at location for array pointer return
1865  *			value
1866  * @param devcountp	points at location for array size return value
1867  *
1868  * @retval 0		success
1869  * @retval ENOMEM	the array allocation failed
1870  */
1871 int
1872 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
1873 {
1874 	int count;
1875 	device_t child;
1876 	device_t *list;
1877 
1878 	count = 0;
1879 	TAILQ_FOREACH(child, &dev->children, link) {
1880 		count++;
1881 	}
1882 
1883 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1884 	if (!list)
1885 		return (ENOMEM);
1886 
1887 	count = 0;
1888 	TAILQ_FOREACH(child, &dev->children, link) {
1889 		list[count] = child;
1890 		count++;
1891 	}
1892 
1893 	*devlistp = list;
1894 	*devcountp = count;
1895 
1896 	return (0);
1897 }
1898 
1899 /**
1900  * @brief Return the current driver for the device or @c NULL if there
1901  * is no driver currently attached
1902  */
1903 driver_t *
1904 device_get_driver(device_t dev)
1905 {
1906 	return (dev->driver);
1907 }
1908 
1909 /**
1910  * @brief Return the current devclass for the device or @c NULL if
1911  * there is none.
1912  */
1913 devclass_t
1914 device_get_devclass(device_t dev)
1915 {
1916 	return (dev->devclass);
1917 }
1918 
1919 /**
1920  * @brief Return the name of the device's devclass or @c NULL if there
1921  * is none.
1922  */
1923 const char *
1924 device_get_name(device_t dev)
1925 {
1926 	if (dev != NULL && dev->devclass)
1927 		return (devclass_get_name(dev->devclass));
1928 	return (NULL);
1929 }
1930 
1931 /**
1932  * @brief Return a string containing the device's devclass name
1933  * followed by an ascii representation of the device's unit number
1934  * (e.g. @c "foo2").
1935  */
1936 const char *
1937 device_get_nameunit(device_t dev)
1938 {
1939 	return (dev->nameunit);
1940 }
1941 
1942 /**
1943  * @brief Return the device's unit number.
1944  */
1945 int
1946 device_get_unit(device_t dev)
1947 {
1948 	return (dev->unit);
1949 }
1950 
1951 /**
1952  * @brief Return the device's description string
1953  */
1954 const char *
1955 device_get_desc(device_t dev)
1956 {
1957 	return (dev->desc);
1958 }
1959 
1960 /**
1961  * @brief Return the device's flags
1962  */
1963 u_int32_t
1964 device_get_flags(device_t dev)
1965 {
1966 	return (dev->devflags);
1967 }
1968 
1969 struct sysctl_ctx_list *
1970 device_get_sysctl_ctx(device_t dev)
1971 {
1972 	return (&dev->sysctl_ctx);
1973 }
1974 
1975 struct sysctl_oid *
1976 device_get_sysctl_tree(device_t dev)
1977 {
1978 	return (dev->sysctl_tree);
1979 }
1980 
1981 /**
1982  * @brief Print the name of the device followed by a colon and a space
1983  *
1984  * @returns the number of characters printed
1985  */
1986 int
1987 device_print_prettyname(device_t dev)
1988 {
1989 	const char *name = device_get_name(dev);
1990 
1991 	if (name == 0)
1992 		return (printf("unknown: "));
1993 	return (printf("%s%d: ", name, device_get_unit(dev)));
1994 }
1995 
1996 /**
1997  * @brief Print the name of the device followed by a colon, a space
1998  * and the result of calling vprintf() with the value of @p fmt and
1999  * the following arguments.
2000  *
2001  * @returns the number of characters printed
2002  */
2003 int
2004 device_printf(device_t dev, const char * fmt, ...)
2005 {
2006 	va_list ap;
2007 	int retval;
2008 
2009 	retval = device_print_prettyname(dev);
2010 	va_start(ap, fmt);
2011 	retval += vprintf(fmt, ap);
2012 	va_end(ap);
2013 	return (retval);
2014 }
2015 
2016 /**
2017  * @internal
2018  */
2019 static void
2020 device_set_desc_internal(device_t dev, const char* desc, int copy)
2021 {
2022 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2023 		free(dev->desc, M_BUS);
2024 		dev->flags &= ~DF_DESCMALLOCED;
2025 		dev->desc = NULL;
2026 	}
2027 
2028 	if (copy && desc) {
2029 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2030 		if (dev->desc) {
2031 			strcpy(dev->desc, desc);
2032 			dev->flags |= DF_DESCMALLOCED;
2033 		}
2034 	} else {
2035 		/* Avoid a -Wcast-qual warning */
2036 		dev->desc = (char *)(uintptr_t) desc;
2037 	}
2038 
2039 	bus_data_generation_update();
2040 }
2041 
2042 /**
2043  * @brief Set the device's description
2044  *
2045  * The value of @c desc should be a string constant that will not
2046  * change (at least until the description is changed in a subsequent
2047  * call to device_set_desc() or device_set_desc_copy()).
2048  */
2049 void
2050 device_set_desc(device_t dev, const char* desc)
2051 {
2052 	device_set_desc_internal(dev, desc, FALSE);
2053 }
2054 
2055 /**
2056  * @brief Set the device's description
2057  *
2058  * The string pointed to by @c desc is copied. Use this function if
2059  * the device description is generated, (e.g. with sprintf()).
2060  */
2061 void
2062 device_set_desc_copy(device_t dev, const char* desc)
2063 {
2064 	device_set_desc_internal(dev, desc, TRUE);
2065 }
2066 
2067 /**
2068  * @brief Set the device's flags
2069  */
2070 void
2071 device_set_flags(device_t dev, u_int32_t flags)
2072 {
2073 	dev->devflags = flags;
2074 }
2075 
2076 /**
2077  * @brief Return the device's softc field
2078  *
2079  * The softc is allocated and zeroed when a driver is attached, based
2080  * on the size field of the driver.
2081  */
2082 void *
2083 device_get_softc(device_t dev)
2084 {
2085 	return (dev->softc);
2086 }
2087 
2088 /**
2089  * @brief Set the device's softc field
2090  *
2091  * Most drivers do not need to use this since the softc is allocated
2092  * automatically when the driver is attached.
2093  */
2094 void
2095 device_set_softc(device_t dev, void *softc)
2096 {
2097 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2098 		free(dev->softc, M_BUS_SC);
2099 	dev->softc = softc;
2100 	if (dev->softc)
2101 		dev->flags |= DF_EXTERNALSOFTC;
2102 	else
2103 		dev->flags &= ~DF_EXTERNALSOFTC;
2104 }
2105 
2106 /**
2107  * @brief Get the device's ivars field
2108  *
2109  * The ivars field is used by the parent device to store per-device
2110  * state (e.g. the physical location of the device or a list of
2111  * resources).
2112  */
2113 void *
2114 device_get_ivars(device_t dev)
2115 {
2116 
2117 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2118 	return (dev->ivars);
2119 }
2120 
2121 /**
2122  * @brief Set the device's ivars field
2123  */
2124 void
2125 device_set_ivars(device_t dev, void * ivars)
2126 {
2127 
2128 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2129 	dev->ivars = ivars;
2130 }
2131 
2132 /**
2133  * @brief Return the device's state
2134  */
2135 device_state_t
2136 device_get_state(device_t dev)
2137 {
2138 	return (dev->state);
2139 }
2140 
2141 /**
2142  * @brief Set the DF_ENABLED flag for the device
2143  */
2144 void
2145 device_enable(device_t dev)
2146 {
2147 	dev->flags |= DF_ENABLED;
2148 }
2149 
2150 /**
2151  * @brief Clear the DF_ENABLED flag for the device
2152  */
2153 void
2154 device_disable(device_t dev)
2155 {
2156 	dev->flags &= ~DF_ENABLED;
2157 }
2158 
2159 /**
2160  * @brief Increment the busy counter for the device
2161  */
2162 void
2163 device_busy(device_t dev)
2164 {
2165 	if (dev->state < DS_ATTACHED)
2166 		panic("device_busy: called for unattached device");
2167 	if (dev->busy == 0 && dev->parent)
2168 		device_busy(dev->parent);
2169 	dev->busy++;
2170 	dev->state = DS_BUSY;
2171 }
2172 
2173 /**
2174  * @brief Decrement the busy counter for the device
2175  */
2176 void
2177 device_unbusy(device_t dev)
2178 {
2179 	if (dev->state != DS_BUSY)
2180 		panic("device_unbusy: called for non-busy device %s",
2181 		    device_get_nameunit(dev));
2182 	dev->busy--;
2183 	if (dev->busy == 0) {
2184 		if (dev->parent)
2185 			device_unbusy(dev->parent);
2186 		dev->state = DS_ATTACHED;
2187 	}
2188 }
2189 
2190 /**
2191  * @brief Set the DF_QUIET flag for the device
2192  */
2193 void
2194 device_quiet(device_t dev)
2195 {
2196 	dev->flags |= DF_QUIET;
2197 }
2198 
2199 /**
2200  * @brief Clear the DF_QUIET flag for the device
2201  */
2202 void
2203 device_verbose(device_t dev)
2204 {
2205 	dev->flags &= ~DF_QUIET;
2206 }
2207 
2208 /**
2209  * @brief Return non-zero if the DF_QUIET flag is set on the device
2210  */
2211 int
2212 device_is_quiet(device_t dev)
2213 {
2214 	return ((dev->flags & DF_QUIET) != 0);
2215 }
2216 
2217 /**
2218  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2219  */
2220 int
2221 device_is_enabled(device_t dev)
2222 {
2223 	return ((dev->flags & DF_ENABLED) != 0);
2224 }
2225 
2226 /**
2227  * @brief Return non-zero if the device was successfully probed
2228  */
2229 int
2230 device_is_alive(device_t dev)
2231 {
2232 	return (dev->state >= DS_ALIVE);
2233 }
2234 
2235 /**
2236  * @brief Return non-zero if the device currently has a driver
2237  * attached to it
2238  */
2239 int
2240 device_is_attached(device_t dev)
2241 {
2242 	return (dev->state >= DS_ATTACHED);
2243 }
2244 
2245 /**
2246  * @brief Set the devclass of a device
2247  * @see devclass_add_device().
2248  */
2249 int
2250 device_set_devclass(device_t dev, const char *classname)
2251 {
2252 	devclass_t dc;
2253 	int error;
2254 
2255 	if (!classname) {
2256 		if (dev->devclass)
2257 			devclass_delete_device(dev->devclass, dev);
2258 		return (0);
2259 	}
2260 
2261 	if (dev->devclass) {
2262 		printf("device_set_devclass: device class already set\n");
2263 		return (EINVAL);
2264 	}
2265 
2266 	dc = devclass_find_internal(classname, NULL, TRUE);
2267 	if (!dc)
2268 		return (ENOMEM);
2269 
2270 	error = devclass_add_device(dc, dev);
2271 
2272 	bus_data_generation_update();
2273 	return (error);
2274 }
2275 
2276 /**
2277  * @brief Set the driver of a device
2278  *
2279  * @retval 0		success
2280  * @retval EBUSY	the device already has a driver attached
2281  * @retval ENOMEM	a memory allocation failure occurred
2282  */
2283 int
2284 device_set_driver(device_t dev, driver_t *driver)
2285 {
2286 	if (dev->state >= DS_ATTACHED)
2287 		return (EBUSY);
2288 
2289 	if (dev->driver == driver)
2290 		return (0);
2291 
2292 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2293 		free(dev->softc, M_BUS_SC);
2294 		dev->softc = NULL;
2295 	}
2296 	kobj_delete((kobj_t) dev, NULL);
2297 	dev->driver = driver;
2298 	if (driver) {
2299 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2300 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2301 			dev->softc = malloc(driver->size, M_BUS_SC,
2302 			    M_NOWAIT | M_ZERO);
2303 			if (!dev->softc) {
2304 				kobj_delete((kobj_t) dev, NULL);
2305 				kobj_init((kobj_t) dev, &null_class);
2306 				dev->driver = NULL;
2307 				return (ENOMEM);
2308 			}
2309 		}
2310 	} else {
2311 		kobj_init((kobj_t) dev, &null_class);
2312 	}
2313 
2314 	bus_data_generation_update();
2315 	return (0);
2316 }
2317 
2318 /**
2319  * @brief Probe a device and attach a driver if possible
2320  *
2321  * This function is the core of the device autoconfiguration
2322  * system. Its purpose is to select a suitable driver for a device and
2323  * then call that driver to initialise the hardware appropriately. The
2324  * driver is selected by calling the DEVICE_PROBE() method of a set of
2325  * candidate drivers and then choosing the driver which returned the
2326  * best value. This driver is then attached to the device using
2327  * device_attach().
2328  *
2329  * The set of suitable drivers is taken from the list of drivers in
2330  * the parent device's devclass. If the device was originally created
2331  * with a specific class name (see device_add_child()), only drivers
2332  * with that name are probed, otherwise all drivers in the devclass
2333  * are probed. If no drivers return successful probe values in the
2334  * parent devclass, the search continues in the parent of that
2335  * devclass (see devclass_get_parent()) if any.
2336  *
2337  * @param dev		the device to initialise
2338  *
2339  * @retval 0		success
2340  * @retval ENXIO	no driver was found
2341  * @retval ENOMEM	memory allocation failure
2342  * @retval non-zero	some other unix error code
2343  */
2344 int
2345 device_probe_and_attach(device_t dev)
2346 {
2347 	int error;
2348 
2349 	GIANT_REQUIRED;
2350 
2351 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2352 		return (0);
2353 
2354 	if (!(dev->flags & DF_ENABLED)) {
2355 		if (bootverbose && device_get_name(dev) != NULL) {
2356 			device_print_prettyname(dev);
2357 			printf("not probed (disabled)\n");
2358 		}
2359 		return (0);
2360 	}
2361 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2362 		if (!(dev->flags & DF_DONENOMATCH)) {
2363 			BUS_PROBE_NOMATCH(dev->parent, dev);
2364 			devnomatch(dev);
2365 			dev->flags |= DF_DONENOMATCH;
2366 		}
2367 		return (error);
2368 	}
2369 	error = device_attach(dev);
2370 
2371 	return (error);
2372 }
2373 
2374 /**
2375  * @brief Attach a device driver to a device
2376  *
2377  * This function is a wrapper around the DEVICE_ATTACH() driver
2378  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2379  * device's sysctl tree, optionally prints a description of the device
2380  * and queues a notification event for user-based device management
2381  * services.
2382  *
2383  * Normally this function is only called internally from
2384  * device_probe_and_attach().
2385  *
2386  * @param dev		the device to initialise
2387  *
2388  * @retval 0		success
2389  * @retval ENXIO	no driver was found
2390  * @retval ENOMEM	memory allocation failure
2391  * @retval non-zero	some other unix error code
2392  */
2393 int
2394 device_attach(device_t dev)
2395 {
2396 	int error;
2397 
2398 	device_sysctl_init(dev);
2399 	if (!device_is_quiet(dev))
2400 		device_print_child(dev->parent, dev);
2401 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2402 		printf("device_attach: %s%d attach returned %d\n",
2403 		    dev->driver->name, dev->unit, error);
2404 		/* Unset the class; set in device_probe_child */
2405 		if (dev->devclass == NULL)
2406 			device_set_devclass(dev, NULL);
2407 		device_set_driver(dev, NULL);
2408 		device_sysctl_fini(dev);
2409 		dev->state = DS_NOTPRESENT;
2410 		return (error);
2411 	}
2412 	device_sysctl_update(dev);
2413 	dev->state = DS_ATTACHED;
2414 	devadded(dev);
2415 	return (0);
2416 }
2417 
2418 /**
2419  * @brief Detach a driver from a device
2420  *
2421  * This function is a wrapper around the DEVICE_DETACH() driver
2422  * method. If the call to DEVICE_DETACH() succeeds, it calls
2423  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
2424  * notification event for user-based device management services and
2425  * cleans up the device's sysctl tree.
2426  *
2427  * @param dev		the device to un-initialise
2428  *
2429  * @retval 0		success
2430  * @retval ENXIO	no driver was found
2431  * @retval ENOMEM	memory allocation failure
2432  * @retval non-zero	some other unix error code
2433  */
2434 int
2435 device_detach(device_t dev)
2436 {
2437 	int error;
2438 
2439 	GIANT_REQUIRED;
2440 
2441 	PDEBUG(("%s", DEVICENAME(dev)));
2442 	if (dev->state == DS_BUSY)
2443 		return (EBUSY);
2444 	if (dev->state != DS_ATTACHED)
2445 		return (0);
2446 
2447 	if ((error = DEVICE_DETACH(dev)) != 0)
2448 		return (error);
2449 	devremoved(dev);
2450 	device_printf(dev, "detached\n");
2451 	if (dev->parent)
2452 		BUS_CHILD_DETACHED(dev->parent, dev);
2453 
2454 	if (!(dev->flags & DF_FIXEDCLASS))
2455 		devclass_delete_device(dev->devclass, dev);
2456 
2457 	dev->state = DS_NOTPRESENT;
2458 	device_set_driver(dev, NULL);
2459 	device_set_desc(dev, NULL);
2460 	device_sysctl_fini(dev);
2461 
2462 	return (0);
2463 }
2464 
2465 /**
2466  * @brief Tells a driver to quiesce itself.
2467  *
2468  * This function is a wrapper around the DEVICE_QUIESCE() driver
2469  * method. If the call to DEVICE_QUIESCE() succeeds.
2470  *
2471  * @param dev		the device to quiesce
2472  *
2473  * @retval 0		success
2474  * @retval ENXIO	no driver was found
2475  * @retval ENOMEM	memory allocation failure
2476  * @retval non-zero	some other unix error code
2477  */
2478 int
2479 device_quiesce(device_t dev)
2480 {
2481 
2482 	PDEBUG(("%s", DEVICENAME(dev)));
2483 	if (dev->state == DS_BUSY)
2484 		return (EBUSY);
2485 	if (dev->state != DS_ATTACHED)
2486 		return (0);
2487 
2488 	return (DEVICE_QUIESCE(dev));
2489 }
2490 
2491 /**
2492  * @brief Notify a device of system shutdown
2493  *
2494  * This function calls the DEVICE_SHUTDOWN() driver method if the
2495  * device currently has an attached driver.
2496  *
2497  * @returns the value returned by DEVICE_SHUTDOWN()
2498  */
2499 int
2500 device_shutdown(device_t dev)
2501 {
2502 	if (dev->state < DS_ATTACHED)
2503 		return (0);
2504 	return (DEVICE_SHUTDOWN(dev));
2505 }
2506 
2507 /**
2508  * @brief Set the unit number of a device
2509  *
2510  * This function can be used to override the unit number used for a
2511  * device (e.g. to wire a device to a pre-configured unit number).
2512  */
2513 int
2514 device_set_unit(device_t dev, int unit)
2515 {
2516 	devclass_t dc;
2517 	int err;
2518 
2519 	dc = device_get_devclass(dev);
2520 	if (unit < dc->maxunit && dc->devices[unit])
2521 		return (EBUSY);
2522 	err = devclass_delete_device(dc, dev);
2523 	if (err)
2524 		return (err);
2525 	dev->unit = unit;
2526 	err = devclass_add_device(dc, dev);
2527 	if (err)
2528 		return (err);
2529 
2530 	bus_data_generation_update();
2531 	return (0);
2532 }
2533 
2534 /*======================================*/
2535 /*
2536  * Some useful method implementations to make life easier for bus drivers.
2537  */
2538 
2539 /**
2540  * @brief Initialise a resource list.
2541  *
2542  * @param rl		the resource list to initialise
2543  */
2544 void
2545 resource_list_init(struct resource_list *rl)
2546 {
2547 	STAILQ_INIT(rl);
2548 }
2549 
2550 /**
2551  * @brief Reclaim memory used by a resource list.
2552  *
2553  * This function frees the memory for all resource entries on the list
2554  * (if any).
2555  *
2556  * @param rl		the resource list to free
2557  */
2558 void
2559 resource_list_free(struct resource_list *rl)
2560 {
2561 	struct resource_list_entry *rle;
2562 
2563 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2564 		if (rle->res)
2565 			panic("resource_list_free: resource entry is busy");
2566 		STAILQ_REMOVE_HEAD(rl, link);
2567 		free(rle, M_BUS);
2568 	}
2569 }
2570 
2571 /**
2572  * @brief Add a resource entry.
2573  *
2574  * This function adds a resource entry using the given @p type, @p
2575  * start, @p end and @p count values. A rid value is chosen by
2576  * searching sequentially for the first unused rid starting at zero.
2577  *
2578  * @param rl		the resource list to edit
2579  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2580  * @param start		the start address of the resource
2581  * @param end		the end address of the resource
2582  * @param count		XXX end-start+1
2583  */
2584 int
2585 resource_list_add_next(struct resource_list *rl, int type, u_long start,
2586     u_long end, u_long count)
2587 {
2588 	int rid;
2589 
2590 	rid = 0;
2591 	while (resource_list_find(rl, type, rid) != NULL)
2592 		rid++;
2593 	resource_list_add(rl, type, rid, start, end, count);
2594 	return (rid);
2595 }
2596 
2597 /**
2598  * @brief Add or modify a resource entry.
2599  *
2600  * If an existing entry exists with the same type and rid, it will be
2601  * modified using the given values of @p start, @p end and @p
2602  * count. If no entry exists, a new one will be created using the
2603  * given values.  The resource list entry that matches is then returned.
2604  *
2605  * @param rl		the resource list to edit
2606  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2607  * @param rid		the resource identifier
2608  * @param start		the start address of the resource
2609  * @param end		the end address of the resource
2610  * @param count		XXX end-start+1
2611  */
2612 struct resource_list_entry *
2613 resource_list_add(struct resource_list *rl, int type, int rid,
2614     u_long start, u_long end, u_long count)
2615 {
2616 	struct resource_list_entry *rle;
2617 
2618 	rle = resource_list_find(rl, type, rid);
2619 	if (!rle) {
2620 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
2621 		    M_NOWAIT);
2622 		if (!rle)
2623 			panic("resource_list_add: can't record entry");
2624 		STAILQ_INSERT_TAIL(rl, rle, link);
2625 		rle->type = type;
2626 		rle->rid = rid;
2627 		rle->res = NULL;
2628 	}
2629 
2630 	if (rle->res)
2631 		panic("resource_list_add: resource entry is busy");
2632 
2633 	rle->start = start;
2634 	rle->end = end;
2635 	rle->count = count;
2636 	return (rle);
2637 }
2638 
2639 /**
2640  * @brief Find a resource entry by type and rid.
2641  *
2642  * @param rl		the resource list to search
2643  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2644  * @param rid		the resource identifier
2645  *
2646  * @returns the resource entry pointer or NULL if there is no such
2647  * entry.
2648  */
2649 struct resource_list_entry *
2650 resource_list_find(struct resource_list *rl, int type, int rid)
2651 {
2652 	struct resource_list_entry *rle;
2653 
2654 	STAILQ_FOREACH(rle, rl, link) {
2655 		if (rle->type == type && rle->rid == rid)
2656 			return (rle);
2657 	}
2658 	return (NULL);
2659 }
2660 
2661 /**
2662  * @brief Delete a resource entry.
2663  *
2664  * @param rl		the resource list to edit
2665  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2666  * @param rid		the resource identifier
2667  */
2668 void
2669 resource_list_delete(struct resource_list *rl, int type, int rid)
2670 {
2671 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
2672 
2673 	if (rle) {
2674 		if (rle->res != NULL)
2675 			panic("resource_list_delete: resource has not been released");
2676 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
2677 		free(rle, M_BUS);
2678 	}
2679 }
2680 
2681 /**
2682  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
2683  *
2684  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
2685  * and passing the allocation up to the parent of @p bus. This assumes
2686  * that the first entry of @c device_get_ivars(child) is a struct
2687  * resource_list. This also handles 'passthrough' allocations where a
2688  * child is a remote descendant of bus by passing the allocation up to
2689  * the parent of bus.
2690  *
2691  * Typically, a bus driver would store a list of child resources
2692  * somewhere in the child device's ivars (see device_get_ivars()) and
2693  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
2694  * then call resource_list_alloc() to perform the allocation.
2695  *
2696  * @param rl		the resource list to allocate from
2697  * @param bus		the parent device of @p child
2698  * @param child		the device which is requesting an allocation
2699  * @param type		the type of resource to allocate
2700  * @param rid		a pointer to the resource identifier
2701  * @param start		hint at the start of the resource range - pass
2702  *			@c 0UL for any start address
2703  * @param end		hint at the end of the resource range - pass
2704  *			@c ~0UL for any end address
2705  * @param count		hint at the size of range required - pass @c 1
2706  *			for any size
2707  * @param flags		any extra flags to control the resource
2708  *			allocation - see @c RF_XXX flags in
2709  *			<sys/rman.h> for details
2710  *
2711  * @returns		the resource which was allocated or @c NULL if no
2712  *			resource could be allocated
2713  */
2714 struct resource *
2715 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
2716     int type, int *rid, u_long start, u_long end, u_long count, u_int flags)
2717 {
2718 	struct resource_list_entry *rle = NULL;
2719 	int passthrough = (device_get_parent(child) != bus);
2720 	int isdefault = (start == 0UL && end == ~0UL);
2721 
2722 	if (passthrough) {
2723 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2724 		    type, rid, start, end, count, flags));
2725 	}
2726 
2727 	rle = resource_list_find(rl, type, *rid);
2728 
2729 	if (!rle)
2730 		return (NULL);		/* no resource of that type/rid */
2731 
2732 	if (rle->res)
2733 		panic("resource_list_alloc: resource entry is busy");
2734 
2735 	if (isdefault) {
2736 		start = rle->start;
2737 		count = ulmax(count, rle->count);
2738 		end = ulmax(rle->end, start + count - 1);
2739 	}
2740 
2741 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2742 	    type, rid, start, end, count, flags);
2743 
2744 	/*
2745 	 * Record the new range.
2746 	 */
2747 	if (rle->res) {
2748 		rle->start = rman_get_start(rle->res);
2749 		rle->end = rman_get_end(rle->res);
2750 		rle->count = count;
2751 	}
2752 
2753 	return (rle->res);
2754 }
2755 
2756 /**
2757  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
2758  *
2759  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
2760  * used with resource_list_alloc().
2761  *
2762  * @param rl		the resource list which was allocated from
2763  * @param bus		the parent device of @p child
2764  * @param child		the device which is requesting a release
2765  * @param type		the type of resource to allocate
2766  * @param rid		the resource identifier
2767  * @param res		the resource to release
2768  *
2769  * @retval 0		success
2770  * @retval non-zero	a standard unix error code indicating what
2771  *			error condition prevented the operation
2772  */
2773 int
2774 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
2775     int type, int rid, struct resource *res)
2776 {
2777 	struct resource_list_entry *rle = NULL;
2778 	int passthrough = (device_get_parent(child) != bus);
2779 	int error;
2780 
2781 	if (passthrough) {
2782 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2783 		    type, rid, res));
2784 	}
2785 
2786 	rle = resource_list_find(rl, type, rid);
2787 
2788 	if (!rle)
2789 		panic("resource_list_release: can't find resource");
2790 	if (!rle->res)
2791 		panic("resource_list_release: resource entry is not busy");
2792 
2793 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2794 	    type, rid, res);
2795 	if (error)
2796 		return (error);
2797 
2798 	rle->res = NULL;
2799 	return (0);
2800 }
2801 
2802 /**
2803  * @brief Print a description of resources in a resource list
2804  *
2805  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
2806  * The name is printed if at least one resource of the given type is available.
2807  * The format is used to print resource start and end.
2808  *
2809  * @param rl		the resource list to print
2810  * @param name		the name of @p type, e.g. @c "memory"
2811  * @param type		type type of resource entry to print
2812  * @param format	printf(9) format string to print resource
2813  *			start and end values
2814  *
2815  * @returns		the number of characters printed
2816  */
2817 int
2818 resource_list_print_type(struct resource_list *rl, const char *name, int type,
2819     const char *format)
2820 {
2821 	struct resource_list_entry *rle;
2822 	int printed, retval;
2823 
2824 	printed = 0;
2825 	retval = 0;
2826 	/* Yes, this is kinda cheating */
2827 	STAILQ_FOREACH(rle, rl, link) {
2828 		if (rle->type == type) {
2829 			if (printed == 0)
2830 				retval += printf(" %s ", name);
2831 			else
2832 				retval += printf(",");
2833 			printed++;
2834 			retval += printf(format, rle->start);
2835 			if (rle->count > 1) {
2836 				retval += printf("-");
2837 				retval += printf(format, rle->start +
2838 						 rle->count - 1);
2839 			}
2840 		}
2841 	}
2842 	return (retval);
2843 }
2844 
2845 /**
2846  * @brief Releases all the resources in a list.
2847  *
2848  * @param rl		The resource list to purge.
2849  *
2850  * @returns		nothing
2851  */
2852 void
2853 resource_list_purge(struct resource_list *rl)
2854 {
2855 	struct resource_list_entry *rle;
2856 
2857 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2858 		if (rle->res)
2859 			bus_release_resource(rman_get_device(rle->res),
2860 			    rle->type, rle->rid, rle->res);
2861 		STAILQ_REMOVE_HEAD(rl, link);
2862 		free(rle, M_BUS);
2863 	}
2864 }
2865 
2866 device_t
2867 bus_generic_add_child(device_t dev, int order, const char *name, int unit)
2868 {
2869 
2870 	return (device_add_child_ordered(dev, order, name, unit));
2871 }
2872 
2873 /**
2874  * @brief Helper function for implementing DEVICE_PROBE()
2875  *
2876  * This function can be used to help implement the DEVICE_PROBE() for
2877  * a bus (i.e. a device which has other devices attached to it). It
2878  * calls the DEVICE_IDENTIFY() method of each driver in the device's
2879  * devclass.
2880  */
2881 int
2882 bus_generic_probe(device_t dev)
2883 {
2884 	devclass_t dc = dev->devclass;
2885 	driverlink_t dl;
2886 
2887 	TAILQ_FOREACH(dl, &dc->drivers, link) {
2888 		DEVICE_IDENTIFY(dl->driver, dev);
2889 	}
2890 
2891 	return (0);
2892 }
2893 
2894 /**
2895  * @brief Helper function for implementing DEVICE_ATTACH()
2896  *
2897  * This function can be used to help implement the DEVICE_ATTACH() for
2898  * a bus. It calls device_probe_and_attach() for each of the device's
2899  * children.
2900  */
2901 int
2902 bus_generic_attach(device_t dev)
2903 {
2904 	device_t child;
2905 
2906 	TAILQ_FOREACH(child, &dev->children, link) {
2907 		device_probe_and_attach(child);
2908 	}
2909 
2910 	return (0);
2911 }
2912 
2913 /**
2914  * @brief Helper function for implementing DEVICE_DETACH()
2915  *
2916  * This function can be used to help implement the DEVICE_DETACH() for
2917  * a bus. It calls device_detach() for each of the device's
2918  * children.
2919  */
2920 int
2921 bus_generic_detach(device_t dev)
2922 {
2923 	device_t child;
2924 	int error;
2925 
2926 	if (dev->state != DS_ATTACHED)
2927 		return (EBUSY);
2928 
2929 	TAILQ_FOREACH(child, &dev->children, link) {
2930 		if ((error = device_detach(child)) != 0)
2931 			return (error);
2932 	}
2933 
2934 	return (0);
2935 }
2936 
2937 /**
2938  * @brief Helper function for implementing DEVICE_SHUTDOWN()
2939  *
2940  * This function can be used to help implement the DEVICE_SHUTDOWN()
2941  * for a bus. It calls device_shutdown() for each of the device's
2942  * children.
2943  */
2944 int
2945 bus_generic_shutdown(device_t dev)
2946 {
2947 	device_t child;
2948 
2949 	TAILQ_FOREACH(child, &dev->children, link) {
2950 		device_shutdown(child);
2951 	}
2952 
2953 	return (0);
2954 }
2955 
2956 /**
2957  * @brief Helper function for implementing DEVICE_SUSPEND()
2958  *
2959  * This function can be used to help implement the DEVICE_SUSPEND()
2960  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
2961  * children. If any call to DEVICE_SUSPEND() fails, the suspend
2962  * operation is aborted and any devices which were suspended are
2963  * resumed immediately by calling their DEVICE_RESUME() methods.
2964  */
2965 int
2966 bus_generic_suspend(device_t dev)
2967 {
2968 	int		error;
2969 	device_t	child, child2;
2970 
2971 	TAILQ_FOREACH(child, &dev->children, link) {
2972 		error = DEVICE_SUSPEND(child);
2973 		if (error) {
2974 			for (child2 = TAILQ_FIRST(&dev->children);
2975 			     child2 && child2 != child;
2976 			     child2 = TAILQ_NEXT(child2, link))
2977 				DEVICE_RESUME(child2);
2978 			return (error);
2979 		}
2980 	}
2981 	return (0);
2982 }
2983 
2984 /**
2985  * @brief Helper function for implementing DEVICE_RESUME()
2986  *
2987  * This function can be used to help implement the DEVICE_RESUME() for
2988  * a bus. It calls DEVICE_RESUME() on each of the device's children.
2989  */
2990 int
2991 bus_generic_resume(device_t dev)
2992 {
2993 	device_t	child;
2994 
2995 	TAILQ_FOREACH(child, &dev->children, link) {
2996 		DEVICE_RESUME(child);
2997 		/* if resume fails, there's nothing we can usefully do... */
2998 	}
2999 	return (0);
3000 }
3001 
3002 /**
3003  * @brief Helper function for implementing BUS_PRINT_CHILD().
3004  *
3005  * This function prints the first part of the ascii representation of
3006  * @p child, including its name, unit and description (if any - see
3007  * device_set_desc()).
3008  *
3009  * @returns the number of characters printed
3010  */
3011 int
3012 bus_print_child_header(device_t dev, device_t child)
3013 {
3014 	int	retval = 0;
3015 
3016 	if (device_get_desc(child)) {
3017 		retval += device_printf(child, "<%s>", device_get_desc(child));
3018 	} else {
3019 		retval += printf("%s", device_get_nameunit(child));
3020 	}
3021 
3022 	return (retval);
3023 }
3024 
3025 /**
3026  * @brief Helper function for implementing BUS_PRINT_CHILD().
3027  *
3028  * This function prints the last part of the ascii representation of
3029  * @p child, which consists of the string @c " on " followed by the
3030  * name and unit of the @p dev.
3031  *
3032  * @returns the number of characters printed
3033  */
3034 int
3035 bus_print_child_footer(device_t dev, device_t child)
3036 {
3037 	return (printf(" on %s\n", device_get_nameunit(dev)));
3038 }
3039 
3040 /**
3041  * @brief Helper function for implementing BUS_PRINT_CHILD().
3042  *
3043  * This function simply calls bus_print_child_header() followed by
3044  * bus_print_child_footer().
3045  *
3046  * @returns the number of characters printed
3047  */
3048 int
3049 bus_generic_print_child(device_t dev, device_t child)
3050 {
3051 	int	retval = 0;
3052 
3053 	retval += bus_print_child_header(dev, child);
3054 	retval += bus_print_child_footer(dev, child);
3055 
3056 	return (retval);
3057 }
3058 
3059 /**
3060  * @brief Stub function for implementing BUS_READ_IVAR().
3061  *
3062  * @returns ENOENT
3063  */
3064 int
3065 bus_generic_read_ivar(device_t dev, device_t child, int index,
3066     uintptr_t * result)
3067 {
3068 	return (ENOENT);
3069 }
3070 
3071 /**
3072  * @brief Stub function for implementing BUS_WRITE_IVAR().
3073  *
3074  * @returns ENOENT
3075  */
3076 int
3077 bus_generic_write_ivar(device_t dev, device_t child, int index,
3078     uintptr_t value)
3079 {
3080 	return (ENOENT);
3081 }
3082 
3083 /**
3084  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
3085  *
3086  * @returns NULL
3087  */
3088 struct resource_list *
3089 bus_generic_get_resource_list(device_t dev, device_t child)
3090 {
3091 	return (NULL);
3092 }
3093 
3094 /**
3095  * @brief Helper function for implementing BUS_DRIVER_ADDED().
3096  *
3097  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
3098  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
3099  * and then calls device_probe_and_attach() for each unattached child.
3100  */
3101 void
3102 bus_generic_driver_added(device_t dev, driver_t *driver)
3103 {
3104 	device_t child;
3105 
3106 	DEVICE_IDENTIFY(driver, dev);
3107 	TAILQ_FOREACH(child, &dev->children, link) {
3108 		if (child->state == DS_NOTPRESENT ||
3109 		    (child->flags & DF_REBID))
3110 			device_probe_and_attach(child);
3111 	}
3112 }
3113 
3114 /**
3115  * @brief Helper function for implementing BUS_SETUP_INTR().
3116  *
3117  * This simple implementation of BUS_SETUP_INTR() simply calls the
3118  * BUS_SETUP_INTR() method of the parent of @p dev.
3119  */
3120 int
3121 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
3122     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
3123     void **cookiep)
3124 {
3125 	/* Propagate up the bus hierarchy until someone handles it. */
3126 	if (dev->parent)
3127 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
3128 		    filter, intr, arg, cookiep));
3129 	return (EINVAL);
3130 }
3131 
3132 /**
3133  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
3134  *
3135  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
3136  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
3137  */
3138 int
3139 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
3140     void *cookie)
3141 {
3142 	/* Propagate up the bus hierarchy until someone handles it. */
3143 	if (dev->parent)
3144 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
3145 	return (EINVAL);
3146 }
3147 
3148 /**
3149  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3150  *
3151  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
3152  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
3153  */
3154 struct resource *
3155 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
3156     u_long start, u_long end, u_long count, u_int flags)
3157 {
3158 	/* Propagate up the bus hierarchy until someone handles it. */
3159 	if (dev->parent)
3160 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
3161 		    start, end, count, flags));
3162 	return (NULL);
3163 }
3164 
3165 /**
3166  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3167  *
3168  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
3169  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
3170  */
3171 int
3172 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
3173     struct resource *r)
3174 {
3175 	/* Propagate up the bus hierarchy until someone handles it. */
3176 	if (dev->parent)
3177 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
3178 		    r));
3179 	return (EINVAL);
3180 }
3181 
3182 /**
3183  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
3184  *
3185  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
3186  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
3187  */
3188 int
3189 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
3190     struct resource *r)
3191 {
3192 	/* Propagate up the bus hierarchy until someone handles it. */
3193 	if (dev->parent)
3194 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
3195 		    r));
3196 	return (EINVAL);
3197 }
3198 
3199 /**
3200  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
3201  *
3202  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
3203  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
3204  */
3205 int
3206 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
3207     int rid, struct resource *r)
3208 {
3209 	/* Propagate up the bus hierarchy until someone handles it. */
3210 	if (dev->parent)
3211 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
3212 		    r));
3213 	return (EINVAL);
3214 }
3215 
3216 /**
3217  * @brief Helper function for implementing BUS_CONFIG_INTR().
3218  *
3219  * This simple implementation of BUS_CONFIG_INTR() simply calls the
3220  * BUS_CONFIG_INTR() method of the parent of @p dev.
3221  */
3222 int
3223 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
3224     enum intr_polarity pol)
3225 {
3226 
3227 	/* Propagate up the bus hierarchy until someone handles it. */
3228 	if (dev->parent)
3229 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
3230 	return (EINVAL);
3231 }
3232 
3233 /**
3234  * @brief Helper function for implementing BUS_GET_DMA_TAG().
3235  *
3236  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
3237  * BUS_GET_DMA_TAG() method of the parent of @p dev.
3238  */
3239 bus_dma_tag_t
3240 bus_generic_get_dma_tag(device_t dev, device_t child)
3241 {
3242 
3243 	/* Propagate up the bus hierarchy until someone handles it. */
3244 	if (dev->parent != NULL)
3245 		return (BUS_GET_DMA_TAG(dev->parent, child));
3246 	return (NULL);
3247 }
3248 
3249 /**
3250  * @brief Helper function for implementing BUS_GET_RESOURCE().
3251  *
3252  * This implementation of BUS_GET_RESOURCE() uses the
3253  * resource_list_find() function to do most of the work. It calls
3254  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3255  * search.
3256  */
3257 int
3258 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
3259     u_long *startp, u_long *countp)
3260 {
3261 	struct resource_list *		rl = NULL;
3262 	struct resource_list_entry *	rle = NULL;
3263 
3264 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3265 	if (!rl)
3266 		return (EINVAL);
3267 
3268 	rle = resource_list_find(rl, type, rid);
3269 	if (!rle)
3270 		return (ENOENT);
3271 
3272 	if (startp)
3273 		*startp = rle->start;
3274 	if (countp)
3275 		*countp = rle->count;
3276 
3277 	return (0);
3278 }
3279 
3280 /**
3281  * @brief Helper function for implementing BUS_SET_RESOURCE().
3282  *
3283  * This implementation of BUS_SET_RESOURCE() uses the
3284  * resource_list_add() function to do most of the work. It calls
3285  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3286  * edit.
3287  */
3288 int
3289 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
3290     u_long start, u_long count)
3291 {
3292 	struct resource_list *		rl = NULL;
3293 
3294 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3295 	if (!rl)
3296 		return (EINVAL);
3297 
3298 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
3299 
3300 	return (0);
3301 }
3302 
3303 /**
3304  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
3305  *
3306  * This implementation of BUS_DELETE_RESOURCE() uses the
3307  * resource_list_delete() function to do most of the work. It calls
3308  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3309  * edit.
3310  */
3311 void
3312 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
3313 {
3314 	struct resource_list *		rl = NULL;
3315 
3316 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3317 	if (!rl)
3318 		return;
3319 
3320 	resource_list_delete(rl, type, rid);
3321 
3322 	return;
3323 }
3324 
3325 /**
3326  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3327  *
3328  * This implementation of BUS_RELEASE_RESOURCE() uses the
3329  * resource_list_release() function to do most of the work. It calls
3330  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3331  */
3332 int
3333 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
3334     int rid, struct resource *r)
3335 {
3336 	struct resource_list *		rl = NULL;
3337 
3338 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3339 	if (!rl)
3340 		return (EINVAL);
3341 
3342 	return (resource_list_release(rl, dev, child, type, rid, r));
3343 }
3344 
3345 /**
3346  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3347  *
3348  * This implementation of BUS_ALLOC_RESOURCE() uses the
3349  * resource_list_alloc() function to do most of the work. It calls
3350  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3351  */
3352 struct resource *
3353 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
3354     int *rid, u_long start, u_long end, u_long count, u_int flags)
3355 {
3356 	struct resource_list *		rl = NULL;
3357 
3358 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3359 	if (!rl)
3360 		return (NULL);
3361 
3362 	return (resource_list_alloc(rl, dev, child, type, rid,
3363 	    start, end, count, flags));
3364 }
3365 
3366 /**
3367  * @brief Helper function for implementing BUS_CHILD_PRESENT().
3368  *
3369  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
3370  * BUS_CHILD_PRESENT() method of the parent of @p dev.
3371  */
3372 int
3373 bus_generic_child_present(device_t dev, device_t child)
3374 {
3375 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
3376 }
3377 
3378 /*
3379  * Some convenience functions to make it easier for drivers to use the
3380  * resource-management functions.  All these really do is hide the
3381  * indirection through the parent's method table, making for slightly
3382  * less-wordy code.  In the future, it might make sense for this code
3383  * to maintain some sort of a list of resources allocated by each device.
3384  */
3385 
3386 int
3387 bus_alloc_resources(device_t dev, struct resource_spec *rs,
3388     struct resource **res)
3389 {
3390 	int i;
3391 
3392 	for (i = 0; rs[i].type != -1; i++)
3393 		res[i] = NULL;
3394 	for (i = 0; rs[i].type != -1; i++) {
3395 		res[i] = bus_alloc_resource_any(dev,
3396 		    rs[i].type, &rs[i].rid, rs[i].flags);
3397 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
3398 			bus_release_resources(dev, rs, res);
3399 			return (ENXIO);
3400 		}
3401 	}
3402 	return (0);
3403 }
3404 
3405 void
3406 bus_release_resources(device_t dev, const struct resource_spec *rs,
3407     struct resource **res)
3408 {
3409 	int i;
3410 
3411 	for (i = 0; rs[i].type != -1; i++)
3412 		if (res[i] != NULL) {
3413 			bus_release_resource(
3414 			    dev, rs[i].type, rs[i].rid, res[i]);
3415 			res[i] = NULL;
3416 		}
3417 }
3418 
3419 /**
3420  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
3421  *
3422  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
3423  * parent of @p dev.
3424  */
3425 struct resource *
3426 bus_alloc_resource(device_t dev, int type, int *rid, u_long start, u_long end,
3427     u_long count, u_int flags)
3428 {
3429 	if (dev->parent == NULL)
3430 		return (NULL);
3431 	return (BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
3432 	    count, flags));
3433 }
3434 
3435 /**
3436  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
3437  *
3438  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
3439  * parent of @p dev.
3440  */
3441 int
3442 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
3443 {
3444 	if (dev->parent == NULL)
3445 		return (EINVAL);
3446 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3447 }
3448 
3449 /**
3450  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
3451  *
3452  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
3453  * parent of @p dev.
3454  */
3455 int
3456 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
3457 {
3458 	if (dev->parent == NULL)
3459 		return (EINVAL);
3460 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3461 }
3462 
3463 /**
3464  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
3465  *
3466  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
3467  * parent of @p dev.
3468  */
3469 int
3470 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
3471 {
3472 	if (dev->parent == NULL)
3473 		return (EINVAL);
3474 	return (BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r));
3475 }
3476 
3477 /**
3478  * @brief Wrapper function for BUS_SETUP_INTR().
3479  *
3480  * This function simply calls the BUS_SETUP_INTR() method of the
3481  * parent of @p dev.
3482  */
3483 int
3484 bus_setup_intr(device_t dev, struct resource *r, int flags,
3485     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
3486 {
3487 	int error;
3488 
3489 	if (dev->parent != NULL) {
3490 		error = BUS_SETUP_INTR(dev->parent, dev, r, flags,
3491 		    filter, handler, arg, cookiep);
3492 		if (error == 0) {
3493 			if (handler != NULL && !(flags & INTR_MPSAFE))
3494 				device_printf(dev, "[GIANT-LOCKED]\n");
3495 			if (bootverbose && (flags & INTR_MPSAFE))
3496 				device_printf(dev, "[MPSAFE]\n");
3497 			if (filter != NULL) {
3498 				if (handler == NULL)
3499 					device_printf(dev, "[FILTER]\n");
3500 				else
3501 					device_printf(dev, "[FILTER+ITHREAD]\n");
3502 			} else
3503 				device_printf(dev, "[ITHREAD]\n");
3504 		}
3505 	} else
3506 		error = EINVAL;
3507 	return (error);
3508 }
3509 
3510 /**
3511  * @brief Wrapper function for BUS_TEARDOWN_INTR().
3512  *
3513  * This function simply calls the BUS_TEARDOWN_INTR() method of the
3514  * parent of @p dev.
3515  */
3516 int
3517 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
3518 {
3519 	if (dev->parent == NULL)
3520 		return (EINVAL);
3521 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
3522 }
3523 
3524 /**
3525  * @brief Wrapper function for BUS_SET_RESOURCE().
3526  *
3527  * This function simply calls the BUS_SET_RESOURCE() method of the
3528  * parent of @p dev.
3529  */
3530 int
3531 bus_set_resource(device_t dev, int type, int rid,
3532     u_long start, u_long count)
3533 {
3534 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
3535 	    start, count));
3536 }
3537 
3538 /**
3539  * @brief Wrapper function for BUS_GET_RESOURCE().
3540  *
3541  * This function simply calls the BUS_GET_RESOURCE() method of the
3542  * parent of @p dev.
3543  */
3544 int
3545 bus_get_resource(device_t dev, int type, int rid,
3546     u_long *startp, u_long *countp)
3547 {
3548 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3549 	    startp, countp));
3550 }
3551 
3552 /**
3553  * @brief Wrapper function for BUS_GET_RESOURCE().
3554  *
3555  * This function simply calls the BUS_GET_RESOURCE() method of the
3556  * parent of @p dev and returns the start value.
3557  */
3558 u_long
3559 bus_get_resource_start(device_t dev, int type, int rid)
3560 {
3561 	u_long start, count;
3562 	int error;
3563 
3564 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3565 	    &start, &count);
3566 	if (error)
3567 		return (0);
3568 	return (start);
3569 }
3570 
3571 /**
3572  * @brief Wrapper function for BUS_GET_RESOURCE().
3573  *
3574  * This function simply calls the BUS_GET_RESOURCE() method of the
3575  * parent of @p dev and returns the count value.
3576  */
3577 u_long
3578 bus_get_resource_count(device_t dev, int type, int rid)
3579 {
3580 	u_long start, count;
3581 	int error;
3582 
3583 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3584 	    &start, &count);
3585 	if (error)
3586 		return (0);
3587 	return (count);
3588 }
3589 
3590 /**
3591  * @brief Wrapper function for BUS_DELETE_RESOURCE().
3592  *
3593  * This function simply calls the BUS_DELETE_RESOURCE() method of the
3594  * parent of @p dev.
3595  */
3596 void
3597 bus_delete_resource(device_t dev, int type, int rid)
3598 {
3599 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
3600 }
3601 
3602 /**
3603  * @brief Wrapper function for BUS_CHILD_PRESENT().
3604  *
3605  * This function simply calls the BUS_CHILD_PRESENT() method of the
3606  * parent of @p dev.
3607  */
3608 int
3609 bus_child_present(device_t child)
3610 {
3611 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
3612 }
3613 
3614 /**
3615  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
3616  *
3617  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
3618  * parent of @p dev.
3619  */
3620 int
3621 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
3622 {
3623 	device_t parent;
3624 
3625 	parent = device_get_parent(child);
3626 	if (parent == NULL) {
3627 		*buf = '\0';
3628 		return (0);
3629 	}
3630 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
3631 }
3632 
3633 /**
3634  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
3635  *
3636  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
3637  * parent of @p dev.
3638  */
3639 int
3640 bus_child_location_str(device_t child, char *buf, size_t buflen)
3641 {
3642 	device_t parent;
3643 
3644 	parent = device_get_parent(child);
3645 	if (parent == NULL) {
3646 		*buf = '\0';
3647 		return (0);
3648 	}
3649 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
3650 }
3651 
3652 /**
3653  * @brief Wrapper function for BUS_GET_DMA_TAG().
3654  *
3655  * This function simply calls the BUS_GET_DMA_TAG() method of the
3656  * parent of @p dev.
3657  */
3658 bus_dma_tag_t
3659 bus_get_dma_tag(device_t dev)
3660 {
3661 	device_t parent;
3662 
3663 	parent = device_get_parent(dev);
3664 	if (parent == NULL)
3665 		return (NULL);
3666 	return (BUS_GET_DMA_TAG(parent, dev));
3667 }
3668 
3669 /* Resume all devices and then notify userland that we're up again. */
3670 static int
3671 root_resume(device_t dev)
3672 {
3673 	int error;
3674 
3675 	error = bus_generic_resume(dev);
3676 	if (error == 0)
3677 		devctl_notify("kern", "power", "resume", NULL);
3678 	return (error);
3679 }
3680 
3681 static int
3682 root_print_child(device_t dev, device_t child)
3683 {
3684 	int	retval = 0;
3685 
3686 	retval += bus_print_child_header(dev, child);
3687 	retval += printf("\n");
3688 
3689 	return (retval);
3690 }
3691 
3692 static int
3693 root_setup_intr(device_t dev, device_t child, driver_intr_t *intr, void *arg,
3694     void **cookiep)
3695 {
3696 	/*
3697 	 * If an interrupt mapping gets to here something bad has happened.
3698 	 */
3699 	panic("root_setup_intr");
3700 }
3701 
3702 /*
3703  * If we get here, assume that the device is permanant and really is
3704  * present in the system.  Removable bus drivers are expected to intercept
3705  * this call long before it gets here.  We return -1 so that drivers that
3706  * really care can check vs -1 or some ERRNO returned higher in the food
3707  * chain.
3708  */
3709 static int
3710 root_child_present(device_t dev, device_t child)
3711 {
3712 	return (-1);
3713 }
3714 
3715 static kobj_method_t root_methods[] = {
3716 	/* Device interface */
3717 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
3718 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
3719 	KOBJMETHOD(device_resume,	root_resume),
3720 
3721 	/* Bus interface */
3722 	KOBJMETHOD(bus_print_child,	root_print_child),
3723 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
3724 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
3725 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
3726 	KOBJMETHOD(bus_child_present,	root_child_present),
3727 
3728 	{ 0, 0 }
3729 };
3730 
3731 static driver_t root_driver = {
3732 	"root",
3733 	root_methods,
3734 	1,			/* no softc */
3735 };
3736 
3737 device_t	root_bus;
3738 devclass_t	root_devclass;
3739 
3740 static int
3741 root_bus_module_handler(module_t mod, int what, void* arg)
3742 {
3743 	switch (what) {
3744 	case MOD_LOAD:
3745 		TAILQ_INIT(&bus_data_devices);
3746 		kobj_class_compile((kobj_class_t) &root_driver);
3747 		root_bus = make_device(NULL, "root", 0);
3748 		root_bus->desc = "System root bus";
3749 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
3750 		root_bus->driver = &root_driver;
3751 		root_bus->state = DS_ATTACHED;
3752 		root_devclass = devclass_find_internal("root", NULL, FALSE);
3753 		devinit();
3754 		return (0);
3755 
3756 	case MOD_SHUTDOWN:
3757 		device_shutdown(root_bus);
3758 		return (0);
3759 	default:
3760 		return (EOPNOTSUPP);
3761 	}
3762 
3763 	return (0);
3764 }
3765 
3766 static moduledata_t root_bus_mod = {
3767 	"rootbus",
3768 	root_bus_module_handler,
3769 	0
3770 };
3771 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
3772 
3773 /**
3774  * @brief Automatically configure devices
3775  *
3776  * This function begins the autoconfiguration process by calling
3777  * device_probe_and_attach() for each child of the @c root0 device.
3778  */
3779 void
3780 root_bus_configure(void)
3781 {
3782 	device_t dev;
3783 
3784 	PDEBUG(("."));
3785 
3786 	TAILQ_FOREACH(dev, &root_bus->children, link) {
3787 		device_probe_and_attach(dev);
3788 	}
3789 }
3790 
3791 /**
3792  * @brief Module handler for registering device drivers
3793  *
3794  * This module handler is used to automatically register device
3795  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
3796  * devclass_add_driver() for the driver described by the
3797  * driver_module_data structure pointed to by @p arg
3798  */
3799 int
3800 driver_module_handler(module_t mod, int what, void *arg)
3801 {
3802 	int error;
3803 	struct driver_module_data *dmd;
3804 	devclass_t bus_devclass;
3805 	kobj_class_t driver;
3806 
3807 	dmd = (struct driver_module_data *)arg;
3808 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
3809 	error = 0;
3810 
3811 	switch (what) {
3812 	case MOD_LOAD:
3813 		if (dmd->dmd_chainevh)
3814 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3815 
3816 		driver = dmd->dmd_driver;
3817 		PDEBUG(("Loading module: driver %s on bus %s",
3818 		    DRIVERNAME(driver), dmd->dmd_busname));
3819 		error = devclass_add_driver(bus_devclass, driver);
3820 		if (error)
3821 			break;
3822 
3823 		/*
3824 		 * If the driver has any base classes, make the
3825 		 * devclass inherit from the devclass of the driver's
3826 		 * first base class. This will allow the system to
3827 		 * search for drivers in both devclasses for children
3828 		 * of a device using this driver.
3829 		 */
3830 		if (driver->baseclasses) {
3831 			const char *parentname;
3832 			parentname = driver->baseclasses[0]->name;
3833 			*dmd->dmd_devclass =
3834 				devclass_find_internal(driver->name,
3835 				    parentname, TRUE);
3836 		} else {
3837 			*dmd->dmd_devclass =
3838 				devclass_find_internal(driver->name, NULL, TRUE);
3839 		}
3840 		break;
3841 
3842 	case MOD_UNLOAD:
3843 		PDEBUG(("Unloading module: driver %s from bus %s",
3844 		    DRIVERNAME(dmd->dmd_driver),
3845 		    dmd->dmd_busname));
3846 		error = devclass_delete_driver(bus_devclass,
3847 		    dmd->dmd_driver);
3848 
3849 		if (!error && dmd->dmd_chainevh)
3850 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3851 		break;
3852 	case MOD_QUIESCE:
3853 		PDEBUG(("Quiesce module: driver %s from bus %s",
3854 		    DRIVERNAME(dmd->dmd_driver),
3855 		    dmd->dmd_busname));
3856 		error = devclass_quiesce_driver(bus_devclass,
3857 		    dmd->dmd_driver);
3858 
3859 		if (!error && dmd->dmd_chainevh)
3860 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3861 		break;
3862 	default:
3863 		error = EOPNOTSUPP;
3864 		break;
3865 	}
3866 
3867 	return (error);
3868 }
3869 
3870 /**
3871  * @brief Enumerate all hinted devices for this bus.
3872  *
3873  * Walks through the hints for this bus and calls the bus_hinted_child
3874  * routine for each one it fines.  It searches first for the specific
3875  * bus that's being probed for hinted children (eg isa0), and then for
3876  * generic children (eg isa).
3877  *
3878  * @param	dev	bus device to enumerate
3879  */
3880 void
3881 bus_enumerate_hinted_children(device_t bus)
3882 {
3883 	int i;
3884 	const char *dname, *busname;
3885 	int dunit;
3886 
3887 	/*
3888 	 * enumerate all devices on the specific bus
3889 	 */
3890 	busname = device_get_nameunit(bus);
3891 	i = 0;
3892 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3893 		BUS_HINTED_CHILD(bus, dname, dunit);
3894 
3895 	/*
3896 	 * and all the generic ones.
3897 	 */
3898 	busname = device_get_name(bus);
3899 	i = 0;
3900 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3901 		BUS_HINTED_CHILD(bus, dname, dunit);
3902 }
3903 
3904 #ifdef BUS_DEBUG
3905 
3906 /* the _short versions avoid iteration by not calling anything that prints
3907  * more than oneliners. I love oneliners.
3908  */
3909 
3910 static void
3911 print_device_short(device_t dev, int indent)
3912 {
3913 	if (!dev)
3914 		return;
3915 
3916 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
3917 	    dev->unit, dev->desc,
3918 	    (dev->parent? "":"no "),
3919 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
3920 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
3921 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
3922 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
3923 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
3924 	    (dev->flags&DF_REBID? "rebiddable,":""),
3925 	    (dev->ivars? "":"no "),
3926 	    (dev->softc? "":"no "),
3927 	    dev->busy));
3928 }
3929 
3930 static void
3931 print_device(device_t dev, int indent)
3932 {
3933 	if (!dev)
3934 		return;
3935 
3936 	print_device_short(dev, indent);
3937 
3938 	indentprintf(("Parent:\n"));
3939 	print_device_short(dev->parent, indent+1);
3940 	indentprintf(("Driver:\n"));
3941 	print_driver_short(dev->driver, indent+1);
3942 	indentprintf(("Devclass:\n"));
3943 	print_devclass_short(dev->devclass, indent+1);
3944 }
3945 
3946 void
3947 print_device_tree_short(device_t dev, int indent)
3948 /* print the device and all its children (indented) */
3949 {
3950 	device_t child;
3951 
3952 	if (!dev)
3953 		return;
3954 
3955 	print_device_short(dev, indent);
3956 
3957 	TAILQ_FOREACH(child, &dev->children, link) {
3958 		print_device_tree_short(child, indent+1);
3959 	}
3960 }
3961 
3962 void
3963 print_device_tree(device_t dev, int indent)
3964 /* print the device and all its children (indented) */
3965 {
3966 	device_t child;
3967 
3968 	if (!dev)
3969 		return;
3970 
3971 	print_device(dev, indent);
3972 
3973 	TAILQ_FOREACH(child, &dev->children, link) {
3974 		print_device_tree(child, indent+1);
3975 	}
3976 }
3977 
3978 static void
3979 print_driver_short(driver_t *driver, int indent)
3980 {
3981 	if (!driver)
3982 		return;
3983 
3984 	indentprintf(("driver %s: softc size = %zd\n",
3985 	    driver->name, driver->size));
3986 }
3987 
3988 static void
3989 print_driver(driver_t *driver, int indent)
3990 {
3991 	if (!driver)
3992 		return;
3993 
3994 	print_driver_short(driver, indent);
3995 }
3996 
3997 
3998 static void
3999 print_driver_list(driver_list_t drivers, int indent)
4000 {
4001 	driverlink_t driver;
4002 
4003 	TAILQ_FOREACH(driver, &drivers, link) {
4004 		print_driver(driver->driver, indent);
4005 	}
4006 }
4007 
4008 static void
4009 print_devclass_short(devclass_t dc, int indent)
4010 {
4011 	if ( !dc )
4012 		return;
4013 
4014 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
4015 }
4016 
4017 static void
4018 print_devclass(devclass_t dc, int indent)
4019 {
4020 	int i;
4021 
4022 	if ( !dc )
4023 		return;
4024 
4025 	print_devclass_short(dc, indent);
4026 	indentprintf(("Drivers:\n"));
4027 	print_driver_list(dc->drivers, indent+1);
4028 
4029 	indentprintf(("Devices:\n"));
4030 	for (i = 0; i < dc->maxunit; i++)
4031 		if (dc->devices[i])
4032 			print_device(dc->devices[i], indent+1);
4033 }
4034 
4035 void
4036 print_devclass_list_short(void)
4037 {
4038 	devclass_t dc;
4039 
4040 	printf("Short listing of devclasses, drivers & devices:\n");
4041 	TAILQ_FOREACH(dc, &devclasses, link) {
4042 		print_devclass_short(dc, 0);
4043 	}
4044 }
4045 
4046 void
4047 print_devclass_list(void)
4048 {
4049 	devclass_t dc;
4050 
4051 	printf("Full listing of devclasses, drivers & devices:\n");
4052 	TAILQ_FOREACH(dc, &devclasses, link) {
4053 		print_devclass(dc, 0);
4054 	}
4055 }
4056 
4057 #endif
4058 
4059 /*
4060  * User-space access to the device tree.
4061  *
4062  * We implement a small set of nodes:
4063  *
4064  * hw.bus			Single integer read method to obtain the
4065  *				current generation count.
4066  * hw.bus.devices		Reads the entire device tree in flat space.
4067  * hw.bus.rman			Resource manager interface
4068  *
4069  * We might like to add the ability to scan devclasses and/or drivers to
4070  * determine what else is currently loaded/available.
4071  */
4072 
4073 static int
4074 sysctl_bus(SYSCTL_HANDLER_ARGS)
4075 {
4076 	struct u_businfo	ubus;
4077 
4078 	ubus.ub_version = BUS_USER_VERSION;
4079 	ubus.ub_generation = bus_data_generation;
4080 
4081 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
4082 }
4083 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
4084     "bus-related data");
4085 
4086 static int
4087 sysctl_devices(SYSCTL_HANDLER_ARGS)
4088 {
4089 	int			*name = (int *)arg1;
4090 	u_int			namelen = arg2;
4091 	int			index;
4092 	struct device		*dev;
4093 	struct u_device		udev;	/* XXX this is a bit big */
4094 	int			error;
4095 
4096 	if (namelen != 2)
4097 		return (EINVAL);
4098 
4099 	if (bus_data_generation_check(name[0]))
4100 		return (EINVAL);
4101 
4102 	index = name[1];
4103 
4104 	/*
4105 	 * Scan the list of devices, looking for the requested index.
4106 	 */
4107 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
4108 		if (index-- == 0)
4109 			break;
4110 	}
4111 	if (dev == NULL)
4112 		return (ENOENT);
4113 
4114 	/*
4115 	 * Populate the return array.
4116 	 */
4117 	bzero(&udev, sizeof(udev));
4118 	udev.dv_handle = (uintptr_t)dev;
4119 	udev.dv_parent = (uintptr_t)dev->parent;
4120 	if (dev->nameunit != NULL)
4121 		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
4122 	if (dev->desc != NULL)
4123 		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
4124 	if (dev->driver != NULL && dev->driver->name != NULL)
4125 		strlcpy(udev.dv_drivername, dev->driver->name,
4126 		    sizeof(udev.dv_drivername));
4127 	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
4128 	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
4129 	udev.dv_devflags = dev->devflags;
4130 	udev.dv_flags = dev->flags;
4131 	udev.dv_state = dev->state;
4132 	error = SYSCTL_OUT(req, &udev, sizeof(udev));
4133 	return (error);
4134 }
4135 
4136 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
4137     "system device tree");
4138 
4139 int
4140 bus_data_generation_check(int generation)
4141 {
4142 	if (generation != bus_data_generation)
4143 		return (1);
4144 
4145 	/* XXX generate optimised lists here? */
4146 	return (0);
4147 }
4148 
4149 void
4150 bus_data_generation_update(void)
4151 {
4152 	bus_data_generation++;
4153 }
4154 
4155 int
4156 bus_free_resource(device_t dev, int type, struct resource *r)
4157 {
4158 	if (r == NULL)
4159 		return (0);
4160 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
4161 }
4162