xref: /freebsd/sys/kern/subr_bus.c (revision 2b743a9e9ddc6736208dc8ca1ce06ce64ad20a19)
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_fini(device_t dev)
311 {
312 	if (dev->sysctl_tree == NULL)
313 		return;
314 	sysctl_ctx_free(&dev->sysctl_ctx);
315 	dev->sysctl_tree = NULL;
316 }
317 
318 /*
319  * /dev/devctl implementation
320  */
321 
322 /*
323  * This design allows only one reader for /dev/devctl.  This is not desirable
324  * in the long run, but will get a lot of hair out of this implementation.
325  * Maybe we should make this device a clonable device.
326  *
327  * Also note: we specifically do not attach a device to the device_t tree
328  * to avoid potential chicken and egg problems.  One could argue that all
329  * of this belongs to the root node.  One could also further argue that the
330  * sysctl interface that we have not might more properly be an ioctl
331  * interface, but at this stage of the game, I'm not inclined to rock that
332  * boat.
333  *
334  * I'm also not sure that the SIGIO support is done correctly or not, as
335  * I copied it from a driver that had SIGIO support that likely hasn't been
336  * tested since 3.4 or 2.2.8!
337  */
338 
339 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
340 static int devctl_disable = 0;
341 TUNABLE_INT("hw.bus.devctl_disable", &devctl_disable);
342 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RW, 0, 0,
343     sysctl_devctl_disable, "I", "devctl disable");
344 
345 static d_open_t		devopen;
346 static d_close_t	devclose;
347 static d_read_t		devread;
348 static d_ioctl_t	devioctl;
349 static d_poll_t		devpoll;
350 
351 static struct cdevsw dev_cdevsw = {
352 	.d_version =	D_VERSION,
353 	.d_flags =	D_NEEDGIANT,
354 	.d_open =	devopen,
355 	.d_close =	devclose,
356 	.d_read =	devread,
357 	.d_ioctl =	devioctl,
358 	.d_poll =	devpoll,
359 	.d_name =	"devctl",
360 };
361 
362 struct dev_event_info
363 {
364 	char *dei_data;
365 	TAILQ_ENTRY(dev_event_info) dei_link;
366 };
367 
368 TAILQ_HEAD(devq, dev_event_info);
369 
370 static struct dev_softc
371 {
372 	int	inuse;
373 	int	nonblock;
374 	struct mtx mtx;
375 	struct cv cv;
376 	struct selinfo sel;
377 	struct devq devq;
378 	struct proc *async_proc;
379 } devsoftc;
380 
381 static struct cdev *devctl_dev;
382 
383 static void
384 devinit(void)
385 {
386 	devctl_dev = make_dev(&dev_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
387 	    "devctl");
388 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
389 	cv_init(&devsoftc.cv, "dev cv");
390 	TAILQ_INIT(&devsoftc.devq);
391 }
392 
393 static int
394 devopen(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
395 {
396 	if (devsoftc.inuse)
397 		return (EBUSY);
398 	/* move to init */
399 	devsoftc.inuse = 1;
400 	devsoftc.nonblock = 0;
401 	devsoftc.async_proc = NULL;
402 	return (0);
403 }
404 
405 static int
406 devclose(struct cdev *dev, int fflag, int devtype, d_thread_t *td)
407 {
408 	devsoftc.inuse = 0;
409 	mtx_lock(&devsoftc.mtx);
410 	cv_broadcast(&devsoftc.cv);
411 	mtx_unlock(&devsoftc.mtx);
412 
413 	return (0);
414 }
415 
416 /*
417  * The read channel for this device is used to report changes to
418  * userland in realtime.  We are required to free the data as well as
419  * the n1 object because we allocate them separately.  Also note that
420  * we return one record at a time.  If you try to read this device a
421  * character at a time, you will lose the rest of the data.  Listening
422  * programs are expected to cope.
423  */
424 static int
425 devread(struct cdev *dev, struct uio *uio, int ioflag)
426 {
427 	struct dev_event_info *n1;
428 	int rv;
429 
430 	mtx_lock(&devsoftc.mtx);
431 	while (TAILQ_EMPTY(&devsoftc.devq)) {
432 		if (devsoftc.nonblock) {
433 			mtx_unlock(&devsoftc.mtx);
434 			return (EAGAIN);
435 		}
436 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
437 		if (rv) {
438 			/*
439 			 * Need to translate ERESTART to EINTR here? -- jake
440 			 */
441 			mtx_unlock(&devsoftc.mtx);
442 			return (rv);
443 		}
444 	}
445 	n1 = TAILQ_FIRST(&devsoftc.devq);
446 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
447 	mtx_unlock(&devsoftc.mtx);
448 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
449 	free(n1->dei_data, M_BUS);
450 	free(n1, M_BUS);
451 	return (rv);
452 }
453 
454 static	int
455 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, d_thread_t *td)
456 {
457 	switch (cmd) {
458 
459 	case FIONBIO:
460 		if (*(int*)data)
461 			devsoftc.nonblock = 1;
462 		else
463 			devsoftc.nonblock = 0;
464 		return (0);
465 	case FIOASYNC:
466 		if (*(int*)data)
467 			devsoftc.async_proc = td->td_proc;
468 		else
469 			devsoftc.async_proc = NULL;
470 		return (0);
471 
472 		/* (un)Support for other fcntl() calls. */
473 	case FIOCLEX:
474 	case FIONCLEX:
475 	case FIONREAD:
476 	case FIOSETOWN:
477 	case FIOGETOWN:
478 	default:
479 		break;
480 	}
481 	return (ENOTTY);
482 }
483 
484 static	int
485 devpoll(struct cdev *dev, int events, d_thread_t *td)
486 {
487 	int	revents = 0;
488 
489 	mtx_lock(&devsoftc.mtx);
490 	if (events & (POLLIN | POLLRDNORM)) {
491 		if (!TAILQ_EMPTY(&devsoftc.devq))
492 			revents = events & (POLLIN | POLLRDNORM);
493 		else
494 			selrecord(td, &devsoftc.sel);
495 	}
496 	mtx_unlock(&devsoftc.mtx);
497 
498 	return (revents);
499 }
500 
501 /**
502  * @brief Queue data to be read from the devctl device
503  *
504  * Generic interface to queue data to the devctl device.  It is
505  * assumed that @p data is properly formatted.  It is further assumed
506  * that @p data is allocated using the M_BUS malloc type.
507  */
508 void
509 devctl_queue_data(char *data)
510 {
511 	struct dev_event_info *n1 = NULL;
512 	struct proc *p;
513 
514 	n1 = malloc(sizeof(*n1), M_BUS, M_NOWAIT);
515 	if (n1 == NULL)
516 		return;
517 	n1->dei_data = data;
518 	mtx_lock(&devsoftc.mtx);
519 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
520 	cv_broadcast(&devsoftc.cv);
521 	mtx_unlock(&devsoftc.mtx);
522 	selwakeup(&devsoftc.sel);
523 	p = devsoftc.async_proc;
524 	if (p != NULL) {
525 		PROC_LOCK(p);
526 		psignal(p, SIGIO);
527 		PROC_UNLOCK(p);
528 	}
529 }
530 
531 /**
532  * @brief Send a 'notification' to userland, using standard ways
533  */
534 void
535 devctl_notify(const char *system, const char *subsystem, const char *type,
536     const char *data)
537 {
538 	int len = 0;
539 	char *msg;
540 
541 	if (system == NULL)
542 		return;		/* BOGUS!  Must specify system. */
543 	if (subsystem == NULL)
544 		return;		/* BOGUS!  Must specify subsystem. */
545 	if (type == NULL)
546 		return;		/* BOGUS!  Must specify type. */
547 	len += strlen(" system=") + strlen(system);
548 	len += strlen(" subsystem=") + strlen(subsystem);
549 	len += strlen(" type=") + strlen(type);
550 	/* add in the data message plus newline. */
551 	if (data != NULL)
552 		len += strlen(data);
553 	len += 3;	/* '!', '\n', and NUL */
554 	msg = malloc(len, M_BUS, M_NOWAIT);
555 	if (msg == NULL)
556 		return;		/* Drop it on the floor */
557 	if (data != NULL)
558 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
559 		    system, subsystem, type, data);
560 	else
561 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
562 		    system, subsystem, type);
563 	devctl_queue_data(msg);
564 }
565 
566 /*
567  * Common routine that tries to make sending messages as easy as possible.
568  * We allocate memory for the data, copy strings into that, but do not
569  * free it unless there's an error.  The dequeue part of the driver should
570  * free the data.  We don't send data when the device is disabled.  We do
571  * send data, even when we have no listeners, because we wish to avoid
572  * races relating to startup and restart of listening applications.
573  *
574  * devaddq is designed to string together the type of event, with the
575  * object of that event, plus the plug and play info and location info
576  * for that event.  This is likely most useful for devices, but less
577  * useful for other consumers of this interface.  Those should use
578  * the devctl_queue_data() interface instead.
579  */
580 static void
581 devaddq(const char *type, const char *what, device_t dev)
582 {
583 	char *data = NULL;
584 	char *loc = NULL;
585 	char *pnp = NULL;
586 	const char *parstr;
587 
588 	if (devctl_disable)
589 		return;
590 	data = malloc(1024, M_BUS, M_NOWAIT);
591 	if (data == NULL)
592 		goto bad;
593 
594 	/* get the bus specific location of this device */
595 	loc = malloc(1024, M_BUS, M_NOWAIT);
596 	if (loc == NULL)
597 		goto bad;
598 	*loc = '\0';
599 	bus_child_location_str(dev, loc, 1024);
600 
601 	/* Get the bus specific pnp info of this device */
602 	pnp = malloc(1024, M_BUS, M_NOWAIT);
603 	if (pnp == NULL)
604 		goto bad;
605 	*pnp = '\0';
606 	bus_child_pnpinfo_str(dev, pnp, 1024);
607 
608 	/* Get the parent of this device, or / if high enough in the tree. */
609 	if (device_get_parent(dev) == NULL)
610 		parstr = ".";	/* Or '/' ? */
611 	else
612 		parstr = device_get_nameunit(device_get_parent(dev));
613 	/* String it all together. */
614 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
615 	  parstr);
616 	free(loc, M_BUS);
617 	free(pnp, M_BUS);
618 	devctl_queue_data(data);
619 	return;
620 bad:
621 	free(pnp, M_BUS);
622 	free(loc, M_BUS);
623 	free(data, M_BUS);
624 	return;
625 }
626 
627 /*
628  * A device was added to the tree.  We are called just after it successfully
629  * attaches (that is, probe and attach success for this device).  No call
630  * is made if a device is merely parented into the tree.  See devnomatch
631  * if probe fails.  If attach fails, no notification is sent (but maybe
632  * we should have a different message for this).
633  */
634 static void
635 devadded(device_t dev)
636 {
637 	char *pnp = NULL;
638 	char *tmp = NULL;
639 
640 	pnp = malloc(1024, M_BUS, M_NOWAIT);
641 	if (pnp == NULL)
642 		goto fail;
643 	tmp = malloc(1024, M_BUS, M_NOWAIT);
644 	if (tmp == NULL)
645 		goto fail;
646 	*pnp = '\0';
647 	bus_child_pnpinfo_str(dev, pnp, 1024);
648 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
649 	devaddq("+", tmp, dev);
650 fail:
651 	if (pnp != NULL)
652 		free(pnp, M_BUS);
653 	if (tmp != NULL)
654 		free(tmp, M_BUS);
655 	return;
656 }
657 
658 /*
659  * A device was removed from the tree.  We are called just before this
660  * happens.
661  */
662 static void
663 devremoved(device_t dev)
664 {
665 	char *pnp = NULL;
666 	char *tmp = NULL;
667 
668 	pnp = malloc(1024, M_BUS, M_NOWAIT);
669 	if (pnp == NULL)
670 		goto fail;
671 	tmp = malloc(1024, M_BUS, M_NOWAIT);
672 	if (tmp == NULL)
673 		goto fail;
674 	*pnp = '\0';
675 	bus_child_pnpinfo_str(dev, pnp, 1024);
676 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
677 	devaddq("-", tmp, dev);
678 fail:
679 	if (pnp != NULL)
680 		free(pnp, M_BUS);
681 	if (tmp != NULL)
682 		free(tmp, M_BUS);
683 	return;
684 }
685 
686 /*
687  * Called when there's no match for this device.  This is only called
688  * the first time that no match happens, so we don't keep getitng this
689  * message.  Should that prove to be undesirable, we can change it.
690  * This is called when all drivers that can attach to a given bus
691  * decline to accept this device.  Other errrors may not be detected.
692  */
693 static void
694 devnomatch(device_t dev)
695 {
696 	devaddq("?", "", dev);
697 }
698 
699 static int
700 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
701 {
702 	struct dev_event_info *n1;
703 	int dis, error;
704 
705 	dis = devctl_disable;
706 	error = sysctl_handle_int(oidp, &dis, 0, req);
707 	if (error || !req->newptr)
708 		return (error);
709 	mtx_lock(&devsoftc.mtx);
710 	devctl_disable = dis;
711 	if (dis) {
712 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
713 			n1 = TAILQ_FIRST(&devsoftc.devq);
714 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
715 			free(n1->dei_data, M_BUS);
716 			free(n1, M_BUS);
717 		}
718 	}
719 	mtx_unlock(&devsoftc.mtx);
720 	return (0);
721 }
722 
723 /* End of /dev/devctl code */
724 
725 TAILQ_HEAD(,device)	bus_data_devices;
726 static int bus_data_generation = 1;
727 
728 kobj_method_t null_methods[] = {
729 	{ 0, 0 }
730 };
731 
732 DEFINE_CLASS(null, null_methods, 0);
733 
734 /*
735  * Devclass implementation
736  */
737 
738 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
739 
740 
741 /**
742  * @internal
743  * @brief Find or create a device class
744  *
745  * If a device class with the name @p classname exists, return it,
746  * otherwise if @p create is non-zero create and return a new device
747  * class.
748  *
749  * If @p parentname is non-NULL, the parent of the devclass is set to
750  * the devclass of that name.
751  *
752  * @param classname	the devclass name to find or create
753  * @param parentname	the parent devclass name or @c NULL
754  * @param create	non-zero to create a devclass
755  */
756 static devclass_t
757 devclass_find_internal(const char *classname, const char *parentname,
758 		       int create)
759 {
760 	devclass_t dc;
761 
762 	PDEBUG(("looking for %s", classname));
763 	if (!classname)
764 		return (NULL);
765 
766 	TAILQ_FOREACH(dc, &devclasses, link) {
767 		if (!strcmp(dc->name, classname))
768 			break;
769 	}
770 
771 	if (create && !dc) {
772 		PDEBUG(("creating %s", classname));
773 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
774 		    M_BUS, M_NOWAIT|M_ZERO);
775 		if (!dc)
776 			return (NULL);
777 		dc->parent = NULL;
778 		dc->name = (char*) (dc + 1);
779 		strcpy(dc->name, classname);
780 		TAILQ_INIT(&dc->drivers);
781 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
782 
783 		bus_data_generation_update();
784 	}
785 
786 	/*
787 	 * If a parent class is specified, then set that as our parent so
788 	 * that this devclass will support drivers for the parent class as
789 	 * well.  If the parent class has the same name don't do this though
790 	 * as it creates a cycle that can trigger an infinite loop in
791 	 * device_probe_child() if a device exists for which there is no
792 	 * suitable driver.
793 	 */
794 	if (parentname && dc && !dc->parent &&
795 	    strcmp(classname, parentname) != 0) {
796 		dc->parent = devclass_find_internal(parentname, NULL, FALSE);
797 	}
798 
799 	return (dc);
800 }
801 
802 /**
803  * @brief Create a device class
804  *
805  * If a device class with the name @p classname exists, return it,
806  * otherwise create and return a new device class.
807  *
808  * @param classname	the devclass name to find or create
809  */
810 devclass_t
811 devclass_create(const char *classname)
812 {
813 	return (devclass_find_internal(classname, NULL, TRUE));
814 }
815 
816 /**
817  * @brief Find a device class
818  *
819  * If a device class with the name @p classname exists, return it,
820  * otherwise return @c NULL.
821  *
822  * @param classname	the devclass name to find
823  */
824 devclass_t
825 devclass_find(const char *classname)
826 {
827 	return (devclass_find_internal(classname, NULL, FALSE));
828 }
829 
830 /**
831  * @brief Add a device driver to a device class
832  *
833  * Add a device driver to a devclass. This is normally called
834  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
835  * all devices in the devclass will be called to allow them to attempt
836  * to re-probe any unmatched children.
837  *
838  * @param dc		the devclass to edit
839  * @param driver	the driver to register
840  */
841 int
842 devclass_add_driver(devclass_t dc, driver_t *driver)
843 {
844 	driverlink_t dl;
845 	int i;
846 
847 	PDEBUG(("%s", DRIVERNAME(driver)));
848 
849 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
850 	if (!dl)
851 		return (ENOMEM);
852 
853 	/*
854 	 * Compile the driver's methods. Also increase the reference count
855 	 * so that the class doesn't get freed when the last instance
856 	 * goes. This means we can safely use static methods and avoids a
857 	 * double-free in devclass_delete_driver.
858 	 */
859 	kobj_class_compile((kobj_class_t) driver);
860 
861 	/*
862 	 * Make sure the devclass which the driver is implementing exists.
863 	 */
864 	devclass_find_internal(driver->name, NULL, TRUE);
865 
866 	dl->driver = driver;
867 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
868 	driver->refs++;		/* XXX: kobj_mtx */
869 
870 	/*
871 	 * Call BUS_DRIVER_ADDED for any existing busses in this class.
872 	 */
873 	for (i = 0; i < dc->maxunit; i++)
874 		if (dc->devices[i])
875 			BUS_DRIVER_ADDED(dc->devices[i], driver);
876 
877 	bus_data_generation_update();
878 	return (0);
879 }
880 
881 /**
882  * @brief Delete a device driver from a device class
883  *
884  * Delete a device driver from a devclass. This is normally called
885  * automatically by DRIVER_MODULE().
886  *
887  * If the driver is currently attached to any devices,
888  * devclass_delete_driver() will first attempt to detach from each
889  * device. If one of the detach calls fails, the driver will not be
890  * deleted.
891  *
892  * @param dc		the devclass to edit
893  * @param driver	the driver to unregister
894  */
895 int
896 devclass_delete_driver(devclass_t busclass, driver_t *driver)
897 {
898 	devclass_t dc = devclass_find(driver->name);
899 	driverlink_t dl;
900 	device_t dev;
901 	int i;
902 	int error;
903 
904 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
905 
906 	if (!dc)
907 		return (0);
908 
909 	/*
910 	 * Find the link structure in the bus' list of drivers.
911 	 */
912 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
913 		if (dl->driver == driver)
914 			break;
915 	}
916 
917 	if (!dl) {
918 		PDEBUG(("%s not found in %s list", driver->name,
919 		    busclass->name));
920 		return (ENOENT);
921 	}
922 
923 	/*
924 	 * Disassociate from any devices.  We iterate through all the
925 	 * devices in the devclass of the driver and detach any which are
926 	 * using the driver and which have a parent in the devclass which
927 	 * we are deleting from.
928 	 *
929 	 * Note that since a driver can be in multiple devclasses, we
930 	 * should not detach devices which are not children of devices in
931 	 * the affected devclass.
932 	 */
933 	for (i = 0; i < dc->maxunit; i++) {
934 		if (dc->devices[i]) {
935 			dev = dc->devices[i];
936 			if (dev->driver == driver && dev->parent &&
937 			    dev->parent->devclass == busclass) {
938 				if ((error = device_detach(dev)) != 0)
939 					return (error);
940 				device_set_driver(dev, NULL);
941 			}
942 		}
943 	}
944 
945 	TAILQ_REMOVE(&busclass->drivers, dl, link);
946 	free(dl, M_BUS);
947 
948 	/* XXX: kobj_mtx */
949 	driver->refs--;
950 	if (driver->refs == 0)
951 		kobj_class_free((kobj_class_t) driver);
952 
953 	bus_data_generation_update();
954 	return (0);
955 }
956 
957 /**
958  * @brief Quiesces a set of device drivers from a device class
959  *
960  * Quiesce a device driver from a devclass. This is normally called
961  * automatically by DRIVER_MODULE().
962  *
963  * If the driver is currently attached to any devices,
964  * devclass_quiesece_driver() will first attempt to quiesce each
965  * device.
966  *
967  * @param dc		the devclass to edit
968  * @param driver	the driver to unregister
969  */
970 int
971 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
972 {
973 	devclass_t dc = devclass_find(driver->name);
974 	driverlink_t dl;
975 	device_t dev;
976 	int i;
977 	int error;
978 
979 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
980 
981 	if (!dc)
982 		return (0);
983 
984 	/*
985 	 * Find the link structure in the bus' list of drivers.
986 	 */
987 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
988 		if (dl->driver == driver)
989 			break;
990 	}
991 
992 	if (!dl) {
993 		PDEBUG(("%s not found in %s list", driver->name,
994 		    busclass->name));
995 		return (ENOENT);
996 	}
997 
998 	/*
999 	 * Quiesce all devices.  We iterate through all the devices in
1000 	 * the devclass of the driver and quiesce any which are using
1001 	 * the driver and which have a parent in the devclass which we
1002 	 * are quiescing.
1003 	 *
1004 	 * Note that since a driver can be in multiple devclasses, we
1005 	 * should not quiesce devices which are not children of
1006 	 * devices in the affected devclass.
1007 	 */
1008 	for (i = 0; i < dc->maxunit; i++) {
1009 		if (dc->devices[i]) {
1010 			dev = dc->devices[i];
1011 			if (dev->driver == driver && dev->parent &&
1012 			    dev->parent->devclass == busclass) {
1013 				if ((error = device_quiesce(dev)) != 0)
1014 					return (error);
1015 			}
1016 		}
1017 	}
1018 
1019 	return (0);
1020 }
1021 
1022 /**
1023  * @internal
1024  */
1025 static driverlink_t
1026 devclass_find_driver_internal(devclass_t dc, const char *classname)
1027 {
1028 	driverlink_t dl;
1029 
1030 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1031 
1032 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1033 		if (!strcmp(dl->driver->name, classname))
1034 			return (dl);
1035 	}
1036 
1037 	PDEBUG(("not found"));
1038 	return (NULL);
1039 }
1040 
1041 /**
1042  * @brief Search a devclass for a driver
1043  *
1044  * This function searches the devclass's list of drivers and returns
1045  * the first driver whose name is @p classname or @c NULL if there is
1046  * no driver of that name.
1047  *
1048  * @param dc		the devclass to search
1049  * @param classname	the driver name to search for
1050  */
1051 kobj_class_t
1052 devclass_find_driver(devclass_t dc, const char *classname)
1053 {
1054 	driverlink_t dl;
1055 
1056 	dl = devclass_find_driver_internal(dc, classname);
1057 	if (dl)
1058 		return (dl->driver);
1059 	return (NULL);
1060 }
1061 
1062 /**
1063  * @brief Return the name of the devclass
1064  */
1065 const char *
1066 devclass_get_name(devclass_t dc)
1067 {
1068 	return (dc->name);
1069 }
1070 
1071 /**
1072  * @brief Find a device given a unit number
1073  *
1074  * @param dc		the devclass to search
1075  * @param unit		the unit number to search for
1076  *
1077  * @returns		the device with the given unit number or @c
1078  *			NULL if there is no such device
1079  */
1080 device_t
1081 devclass_get_device(devclass_t dc, int unit)
1082 {
1083 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1084 		return (NULL);
1085 	return (dc->devices[unit]);
1086 }
1087 
1088 /**
1089  * @brief Find the softc field of a device given a unit number
1090  *
1091  * @param dc		the devclass to search
1092  * @param unit		the unit number to search for
1093  *
1094  * @returns		the softc field of the device with the given
1095  *			unit number or @c NULL if there is no such
1096  *			device
1097  */
1098 void *
1099 devclass_get_softc(devclass_t dc, int unit)
1100 {
1101 	device_t dev;
1102 
1103 	dev = devclass_get_device(dc, unit);
1104 	if (!dev)
1105 		return (NULL);
1106 
1107 	return (device_get_softc(dev));
1108 }
1109 
1110 /**
1111  * @brief Get a list of devices in the devclass
1112  *
1113  * An array containing a list of all the devices in the given devclass
1114  * is allocated and returned in @p *devlistp. The number of devices
1115  * in the array is returned in @p *devcountp. The caller should free
1116  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1117  *
1118  * @param dc		the devclass to examine
1119  * @param devlistp	points at location for array pointer return
1120  *			value
1121  * @param devcountp	points at location for array size return value
1122  *
1123  * @retval 0		success
1124  * @retval ENOMEM	the array allocation failed
1125  */
1126 int
1127 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1128 {
1129 	int count, i;
1130 	device_t *list;
1131 
1132 	count = devclass_get_count(dc);
1133 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1134 	if (!list)
1135 		return (ENOMEM);
1136 
1137 	count = 0;
1138 	for (i = 0; i < dc->maxunit; i++) {
1139 		if (dc->devices[i]) {
1140 			list[count] = dc->devices[i];
1141 			count++;
1142 		}
1143 	}
1144 
1145 	*devlistp = list;
1146 	*devcountp = count;
1147 
1148 	return (0);
1149 }
1150 
1151 /**
1152  * @brief Get a list of drivers in the devclass
1153  *
1154  * An array containing a list of pointers to all the drivers in the
1155  * given devclass is allocated and returned in @p *listp.  The number
1156  * of drivers in the array is returned in @p *countp. The caller should
1157  * free the array using @c free(p, M_TEMP).
1158  *
1159  * @param dc		the devclass to examine
1160  * @param listp		gives location for array pointer return value
1161  * @param countp	gives location for number of array elements
1162  *			return value
1163  *
1164  * @retval 0		success
1165  * @retval ENOMEM	the array allocation failed
1166  */
1167 int
1168 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1169 {
1170 	driverlink_t dl;
1171 	driver_t **list;
1172 	int count;
1173 
1174 	count = 0;
1175 	TAILQ_FOREACH(dl, &dc->drivers, link)
1176 		count++;
1177 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1178 	if (list == NULL)
1179 		return (ENOMEM);
1180 
1181 	count = 0;
1182 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1183 		list[count] = dl->driver;
1184 		count++;
1185 	}
1186 	*listp = list;
1187 	*countp = count;
1188 
1189 	return (0);
1190 }
1191 
1192 /**
1193  * @brief Get the number of devices in a devclass
1194  *
1195  * @param dc		the devclass to examine
1196  */
1197 int
1198 devclass_get_count(devclass_t dc)
1199 {
1200 	int count, i;
1201 
1202 	count = 0;
1203 	for (i = 0; i < dc->maxunit; i++)
1204 		if (dc->devices[i])
1205 			count++;
1206 	return (count);
1207 }
1208 
1209 /**
1210  * @brief Get the maximum unit number used in a devclass
1211  *
1212  * Note that this is one greater than the highest currently-allocated
1213  * unit.
1214  *
1215  * @param dc		the devclass to examine
1216  */
1217 int
1218 devclass_get_maxunit(devclass_t dc)
1219 {
1220 	return (dc->maxunit);
1221 }
1222 
1223 /**
1224  * @brief Find a free unit number in a devclass
1225  *
1226  * This function searches for the first unused unit number greater
1227  * that or equal to @p unit.
1228  *
1229  * @param dc		the devclass to examine
1230  * @param unit		the first unit number to check
1231  */
1232 int
1233 devclass_find_free_unit(devclass_t dc, int unit)
1234 {
1235 	if (dc == NULL)
1236 		return (unit);
1237 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1238 		unit++;
1239 	return (unit);
1240 }
1241 
1242 /**
1243  * @brief Set the parent of a devclass
1244  *
1245  * The parent class is normally initialised automatically by
1246  * DRIVER_MODULE().
1247  *
1248  * @param dc		the devclass to edit
1249  * @param pdc		the new parent devclass
1250  */
1251 void
1252 devclass_set_parent(devclass_t dc, devclass_t pdc)
1253 {
1254 	dc->parent = pdc;
1255 }
1256 
1257 /**
1258  * @brief Get the parent of a devclass
1259  *
1260  * @param dc		the devclass to examine
1261  */
1262 devclass_t
1263 devclass_get_parent(devclass_t dc)
1264 {
1265 	return (dc->parent);
1266 }
1267 
1268 struct sysctl_ctx_list *
1269 devclass_get_sysctl_ctx(devclass_t dc)
1270 {
1271 	return (&dc->sysctl_ctx);
1272 }
1273 
1274 struct sysctl_oid *
1275 devclass_get_sysctl_tree(devclass_t dc)
1276 {
1277 	return (dc->sysctl_tree);
1278 }
1279 
1280 /**
1281  * @internal
1282  * @brief Allocate a unit number
1283  *
1284  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1285  * will do). The allocated unit number is returned in @p *unitp.
1286 
1287  * @param dc		the devclass to allocate from
1288  * @param unitp		points at the location for the allocated unit
1289  *			number
1290  *
1291  * @retval 0		success
1292  * @retval EEXIST	the requested unit number is already allocated
1293  * @retval ENOMEM	memory allocation failure
1294  */
1295 static int
1296 devclass_alloc_unit(devclass_t dc, int *unitp)
1297 {
1298 	int unit = *unitp;
1299 
1300 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1301 
1302 	/* If we were given a wired unit number, check for existing device */
1303 	/* XXX imp XXX */
1304 	if (unit != -1) {
1305 		if (unit >= 0 && unit < dc->maxunit &&
1306 		    dc->devices[unit] != NULL) {
1307 			if (bootverbose)
1308 				printf("%s: %s%d already exists; skipping it\n",
1309 				    dc->name, dc->name, *unitp);
1310 			return (EEXIST);
1311 		}
1312 	} else {
1313 		/* Unwired device, find the next available slot for it */
1314 		unit = 0;
1315 		while (unit < dc->maxunit && dc->devices[unit] != NULL)
1316 			unit++;
1317 	}
1318 
1319 	/*
1320 	 * We've selected a unit beyond the length of the table, so let's
1321 	 * extend the table to make room for all units up to and including
1322 	 * this one.
1323 	 */
1324 	if (unit >= dc->maxunit) {
1325 		device_t *newlist;
1326 		int newsize;
1327 
1328 		newsize = roundup((unit + 1), MINALLOCSIZE / sizeof(device_t));
1329 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1330 		if (!newlist)
1331 			return (ENOMEM);
1332 		bcopy(dc->devices, newlist, sizeof(device_t) * dc->maxunit);
1333 		bzero(newlist + dc->maxunit,
1334 		    sizeof(device_t) * (newsize - dc->maxunit));
1335 		if (dc->devices)
1336 			free(dc->devices, M_BUS);
1337 		dc->devices = newlist;
1338 		dc->maxunit = newsize;
1339 	}
1340 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1341 
1342 	*unitp = unit;
1343 	return (0);
1344 }
1345 
1346 /**
1347  * @internal
1348  * @brief Add a device to a devclass
1349  *
1350  * A unit number is allocated for the device (using the device's
1351  * preferred unit number if any) and the device is registered in the
1352  * devclass. This allows the device to be looked up by its unit
1353  * number, e.g. by decoding a dev_t minor number.
1354  *
1355  * @param dc		the devclass to add to
1356  * @param dev		the device to add
1357  *
1358  * @retval 0		success
1359  * @retval EEXIST	the requested unit number is already allocated
1360  * @retval ENOMEM	memory allocation failure
1361  */
1362 static int
1363 devclass_add_device(devclass_t dc, device_t dev)
1364 {
1365 	int buflen, error;
1366 
1367 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1368 
1369 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, dev->unit);
1370 	if (buflen < 0)
1371 		return (ENOMEM);
1372 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1373 	if (!dev->nameunit)
1374 		return (ENOMEM);
1375 
1376 	if ((error = devclass_alloc_unit(dc, &dev->unit)) != 0) {
1377 		free(dev->nameunit, M_BUS);
1378 		dev->nameunit = NULL;
1379 		return (error);
1380 	}
1381 	dc->devices[dev->unit] = dev;
1382 	dev->devclass = dc;
1383 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1384 
1385 	return (0);
1386 }
1387 
1388 /**
1389  * @internal
1390  * @brief Delete a device from a devclass
1391  *
1392  * The device is removed from the devclass's device list and its unit
1393  * number is freed.
1394 
1395  * @param dc		the devclass to delete from
1396  * @param dev		the device to delete
1397  *
1398  * @retval 0		success
1399  */
1400 static int
1401 devclass_delete_device(devclass_t dc, device_t dev)
1402 {
1403 	if (!dc || !dev)
1404 		return (0);
1405 
1406 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1407 
1408 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1409 		panic("devclass_delete_device: inconsistent device class");
1410 	dc->devices[dev->unit] = NULL;
1411 	if (dev->flags & DF_WILDCARD)
1412 		dev->unit = -1;
1413 	dev->devclass = NULL;
1414 	free(dev->nameunit, M_BUS);
1415 	dev->nameunit = NULL;
1416 
1417 	return (0);
1418 }
1419 
1420 /**
1421  * @internal
1422  * @brief Make a new device and add it as a child of @p parent
1423  *
1424  * @param parent	the parent of the new device
1425  * @param name		the devclass name of the new device or @c NULL
1426  *			to leave the devclass unspecified
1427  * @parem unit		the unit number of the new device of @c -1 to
1428  *			leave the unit number unspecified
1429  *
1430  * @returns the new device
1431  */
1432 static device_t
1433 make_device(device_t parent, const char *name, int unit)
1434 {
1435 	device_t dev;
1436 	devclass_t dc;
1437 
1438 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1439 
1440 	if (name) {
1441 		dc = devclass_find_internal(name, NULL, TRUE);
1442 		if (!dc) {
1443 			printf("make_device: can't find device class %s\n",
1444 			    name);
1445 			return (NULL);
1446 		}
1447 	} else {
1448 		dc = NULL;
1449 	}
1450 
1451 	dev = malloc(sizeof(struct device), M_BUS, M_NOWAIT|M_ZERO);
1452 	if (!dev)
1453 		return (NULL);
1454 
1455 	dev->parent = parent;
1456 	TAILQ_INIT(&dev->children);
1457 	kobj_init((kobj_t) dev, &null_class);
1458 	dev->driver = NULL;
1459 	dev->devclass = NULL;
1460 	dev->unit = unit;
1461 	dev->nameunit = NULL;
1462 	dev->desc = NULL;
1463 	dev->busy = 0;
1464 	dev->devflags = 0;
1465 	dev->flags = DF_ENABLED;
1466 	dev->order = 0;
1467 	if (unit == -1)
1468 		dev->flags |= DF_WILDCARD;
1469 	if (name) {
1470 		dev->flags |= DF_FIXEDCLASS;
1471 		if (devclass_add_device(dc, dev)) {
1472 			kobj_delete((kobj_t) dev, M_BUS);
1473 			return (NULL);
1474 		}
1475 	}
1476 	dev->ivars = NULL;
1477 	dev->softc = NULL;
1478 
1479 	dev->state = DS_NOTPRESENT;
1480 
1481 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1482 	bus_data_generation_update();
1483 
1484 	return (dev);
1485 }
1486 
1487 /**
1488  * @internal
1489  * @brief Print a description of a device.
1490  */
1491 static int
1492 device_print_child(device_t dev, device_t child)
1493 {
1494 	int retval = 0;
1495 
1496 	if (device_is_alive(child))
1497 		retval += BUS_PRINT_CHILD(dev, child);
1498 	else
1499 		retval += device_printf(child, " not found\n");
1500 
1501 	return (retval);
1502 }
1503 
1504 /**
1505  * @brief Create a new device
1506  *
1507  * This creates a new device and adds it as a child of an existing
1508  * parent device. The new device will be added after the last existing
1509  * child with order zero.
1510  *
1511  * @param dev		the device which will be the parent of the
1512  *			new child device
1513  * @param name		devclass name for new device or @c NULL if not
1514  *			specified
1515  * @param unit		unit number for new device or @c -1 if not
1516  *			specified
1517  *
1518  * @returns		the new device
1519  */
1520 device_t
1521 device_add_child(device_t dev, const char *name, int unit)
1522 {
1523 	return (device_add_child_ordered(dev, 0, name, unit));
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 the same order.
1532  *
1533  * @param dev		the device which will be the parent of the
1534  *			new child device
1535  * @param order		a value which is used to partially sort the
1536  *			children of @p dev - devices created using
1537  *			lower values of @p order appear first in @p
1538  *			dev's list of children
1539  * @param name		devclass name for new device or @c NULL if not
1540  *			specified
1541  * @param unit		unit number for new device or @c -1 if not
1542  *			specified
1543  *
1544  * @returns		the new device
1545  */
1546 device_t
1547 device_add_child_ordered(device_t dev, int order, const char *name, int unit)
1548 {
1549 	device_t child;
1550 	device_t place;
1551 
1552 	PDEBUG(("%s at %s with order %d as unit %d",
1553 	    name, DEVICENAME(dev), order, unit));
1554 
1555 	child = make_device(dev, name, unit);
1556 	if (child == NULL)
1557 		return (child);
1558 	child->order = order;
1559 
1560 	TAILQ_FOREACH(place, &dev->children, link) {
1561 		if (place->order > order)
1562 			break;
1563 	}
1564 
1565 	if (place) {
1566 		/*
1567 		 * The device 'place' is the first device whose order is
1568 		 * greater than the new child.
1569 		 */
1570 		TAILQ_INSERT_BEFORE(place, child, link);
1571 	} else {
1572 		/*
1573 		 * The new child's order is greater or equal to the order of
1574 		 * any existing device. Add the child to the tail of the list.
1575 		 */
1576 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1577 	}
1578 
1579 	bus_data_generation_update();
1580 	return (child);
1581 }
1582 
1583 /**
1584  * @brief Delete a device
1585  *
1586  * This function deletes a device along with all of its children. If
1587  * the device currently has a driver attached to it, the device is
1588  * detached first using device_detach().
1589  *
1590  * @param dev		the parent device
1591  * @param child		the device to delete
1592  *
1593  * @retval 0		success
1594  * @retval non-zero	a unit error code describing the error
1595  */
1596 int
1597 device_delete_child(device_t dev, device_t child)
1598 {
1599 	int error;
1600 	device_t grandchild;
1601 
1602 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1603 
1604 	/* remove children first */
1605 	while ( (grandchild = TAILQ_FIRST(&child->children)) ) {
1606 		error = device_delete_child(child, grandchild);
1607 		if (error)
1608 			return (error);
1609 	}
1610 
1611 	if ((error = device_detach(child)) != 0)
1612 		return (error);
1613 	if (child->devclass)
1614 		devclass_delete_device(child->devclass, child);
1615 	TAILQ_REMOVE(&dev->children, child, link);
1616 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1617 	kobj_delete((kobj_t) child, M_BUS);
1618 
1619 	bus_data_generation_update();
1620 	return (0);
1621 }
1622 
1623 /**
1624  * @brief Find a device given a unit number
1625  *
1626  * This is similar to devclass_get_devices() but only searches for
1627  * devices which have @p dev as a parent.
1628  *
1629  * @param dev		the parent device to search
1630  * @param unit		the unit number to search for.  If the unit is -1,
1631  *			return the first child of @p dev which has name
1632  *			@p classname (that is, the one with the lowest unit.)
1633  *
1634  * @returns		the device with the given unit number or @c
1635  *			NULL if there is no such device
1636  */
1637 device_t
1638 device_find_child(device_t dev, const char *classname, int unit)
1639 {
1640 	devclass_t dc;
1641 	device_t child;
1642 
1643 	dc = devclass_find(classname);
1644 	if (!dc)
1645 		return (NULL);
1646 
1647 	if (unit != -1) {
1648 		child = devclass_get_device(dc, unit);
1649 		if (child && child->parent == dev)
1650 			return (child);
1651 	} else {
1652 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
1653 			child = devclass_get_device(dc, unit);
1654 			if (child && child->parent == dev)
1655 				return (child);
1656 		}
1657 	}
1658 	return (NULL);
1659 }
1660 
1661 /**
1662  * @internal
1663  */
1664 static driverlink_t
1665 first_matching_driver(devclass_t dc, device_t dev)
1666 {
1667 	if (dev->devclass)
1668 		return (devclass_find_driver_internal(dc, dev->devclass->name));
1669 	return (TAILQ_FIRST(&dc->drivers));
1670 }
1671 
1672 /**
1673  * @internal
1674  */
1675 static driverlink_t
1676 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
1677 {
1678 	if (dev->devclass) {
1679 		driverlink_t dl;
1680 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
1681 			if (!strcmp(dev->devclass->name, dl->driver->name))
1682 				return (dl);
1683 		return (NULL);
1684 	}
1685 	return (TAILQ_NEXT(last, link));
1686 }
1687 
1688 /**
1689  * @internal
1690  */
1691 int
1692 device_probe_child(device_t dev, device_t child)
1693 {
1694 	devclass_t dc;
1695 	driverlink_t best = NULL;
1696 	driverlink_t dl;
1697 	int result, pri = 0;
1698 	int hasclass = (child->devclass != 0);
1699 
1700 	GIANT_REQUIRED;
1701 
1702 	dc = dev->devclass;
1703 	if (!dc)
1704 		panic("device_probe_child: parent device has no devclass");
1705 
1706 	/*
1707 	 * If the state is already probed, then return.  However, don't
1708 	 * return if we can rebid this object.
1709 	 */
1710 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
1711 		return (0);
1712 
1713 	for (; dc; dc = dc->parent) {
1714 		for (dl = first_matching_driver(dc, child);
1715 		     dl;
1716 		     dl = next_matching_driver(dc, child, dl)) {
1717 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
1718 			device_set_driver(child, dl->driver);
1719 			if (!hasclass)
1720 				device_set_devclass(child, dl->driver->name);
1721 
1722 			/* Fetch any flags for the device before probing. */
1723 			resource_int_value(dl->driver->name, child->unit,
1724 			    "flags", &child->devflags);
1725 
1726 			result = DEVICE_PROBE(child);
1727 
1728 			/* Reset flags and devclass before the next probe. */
1729 			child->devflags = 0;
1730 			if (!hasclass)
1731 				device_set_devclass(child, NULL);
1732 
1733 			/*
1734 			 * If the driver returns SUCCESS, there can be
1735 			 * no higher match for this device.
1736 			 */
1737 			if (result == 0) {
1738 				best = dl;
1739 				pri = 0;
1740 				break;
1741 			}
1742 
1743 			/*
1744 			 * The driver returned an error so it
1745 			 * certainly doesn't match.
1746 			 */
1747 			if (result > 0) {
1748 				device_set_driver(child, NULL);
1749 				continue;
1750 			}
1751 
1752 			/*
1753 			 * A priority lower than SUCCESS, remember the
1754 			 * best matching driver. Initialise the value
1755 			 * of pri for the first match.
1756 			 */
1757 			if (best == NULL || result > pri) {
1758 				best = dl;
1759 				pri = result;
1760 				continue;
1761 			}
1762 		}
1763 		/*
1764 		 * If we have an unambiguous match in this devclass,
1765 		 * don't look in the parent.
1766 		 */
1767 		if (best && pri == 0)
1768 			break;
1769 	}
1770 
1771 	/*
1772 	 * If we found a driver, change state and initialise the devclass.
1773 	 */
1774 	/* XXX What happens if we rebid and got no best? */
1775 	if (best) {
1776 		/*
1777 		 * If this device was atached, and we were asked to
1778 		 * rescan, and it is a different driver, then we have
1779 		 * to detach the old driver and reattach this new one.
1780 		 * Note, we don't have to check for DF_REBID here
1781 		 * because if the state is > DS_ALIVE, we know it must
1782 		 * be.
1783 		 *
1784 		 * This assumes that all DF_REBID drivers can have
1785 		 * their probe routine called at any time and that
1786 		 * they are idempotent as well as completely benign in
1787 		 * normal operations.
1788 		 *
1789 		 * We also have to make sure that the detach
1790 		 * succeeded, otherwise we fail the operation (or
1791 		 * maybe it should just fail silently?  I'm torn).
1792 		 */
1793 		if (child->state > DS_ALIVE && best->driver != child->driver)
1794 			if ((result = device_detach(dev)) != 0)
1795 				return (result);
1796 
1797 		/* Set the winning driver, devclass, and flags. */
1798 		if (!child->devclass)
1799 			device_set_devclass(child, best->driver->name);
1800 		device_set_driver(child, best->driver);
1801 		resource_int_value(best->driver->name, child->unit,
1802 		    "flags", &child->devflags);
1803 
1804 		if (pri < 0) {
1805 			/*
1806 			 * A bit bogus. Call the probe method again to make
1807 			 * sure that we have the right description.
1808 			 */
1809 			DEVICE_PROBE(child);
1810 #if 0
1811 			child->flags |= DF_REBID;
1812 #endif
1813 		} else
1814 			child->flags &= ~DF_REBID;
1815 		child->state = DS_ALIVE;
1816 
1817 		bus_data_generation_update();
1818 		return (0);
1819 	}
1820 
1821 	return (ENXIO);
1822 }
1823 
1824 /**
1825  * @brief Return the parent of a device
1826  */
1827 device_t
1828 device_get_parent(device_t dev)
1829 {
1830 	return (dev->parent);
1831 }
1832 
1833 /**
1834  * @brief Get a list of children of a device
1835  *
1836  * An array containing a list of all the children of the given device
1837  * is allocated and returned in @p *devlistp. The number of devices
1838  * in the array is returned in @p *devcountp. The caller should free
1839  * the array using @c free(p, M_TEMP).
1840  *
1841  * @param dev		the device to examine
1842  * @param devlistp	points at location for array pointer return
1843  *			value
1844  * @param devcountp	points at location for array size return value
1845  *
1846  * @retval 0		success
1847  * @retval ENOMEM	the array allocation failed
1848  */
1849 int
1850 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
1851 {
1852 	int count;
1853 	device_t child;
1854 	device_t *list;
1855 
1856 	count = 0;
1857 	TAILQ_FOREACH(child, &dev->children, link) {
1858 		count++;
1859 	}
1860 
1861 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1862 	if (!list)
1863 		return (ENOMEM);
1864 
1865 	count = 0;
1866 	TAILQ_FOREACH(child, &dev->children, link) {
1867 		list[count] = child;
1868 		count++;
1869 	}
1870 
1871 	*devlistp = list;
1872 	*devcountp = count;
1873 
1874 	return (0);
1875 }
1876 
1877 /**
1878  * @brief Return the current driver for the device or @c NULL if there
1879  * is no driver currently attached
1880  */
1881 driver_t *
1882 device_get_driver(device_t dev)
1883 {
1884 	return (dev->driver);
1885 }
1886 
1887 /**
1888  * @brief Return the current devclass for the device or @c NULL if
1889  * there is none.
1890  */
1891 devclass_t
1892 device_get_devclass(device_t dev)
1893 {
1894 	return (dev->devclass);
1895 }
1896 
1897 /**
1898  * @brief Return the name of the device's devclass or @c NULL if there
1899  * is none.
1900  */
1901 const char *
1902 device_get_name(device_t dev)
1903 {
1904 	if (dev != NULL && dev->devclass)
1905 		return (devclass_get_name(dev->devclass));
1906 	return (NULL);
1907 }
1908 
1909 /**
1910  * @brief Return a string containing the device's devclass name
1911  * followed by an ascii representation of the device's unit number
1912  * (e.g. @c "foo2").
1913  */
1914 const char *
1915 device_get_nameunit(device_t dev)
1916 {
1917 	return (dev->nameunit);
1918 }
1919 
1920 /**
1921  * @brief Return the device's unit number.
1922  */
1923 int
1924 device_get_unit(device_t dev)
1925 {
1926 	return (dev->unit);
1927 }
1928 
1929 /**
1930  * @brief Return the device's description string
1931  */
1932 const char *
1933 device_get_desc(device_t dev)
1934 {
1935 	return (dev->desc);
1936 }
1937 
1938 /**
1939  * @brief Return the device's flags
1940  */
1941 u_int32_t
1942 device_get_flags(device_t dev)
1943 {
1944 	return (dev->devflags);
1945 }
1946 
1947 struct sysctl_ctx_list *
1948 device_get_sysctl_ctx(device_t dev)
1949 {
1950 	return (&dev->sysctl_ctx);
1951 }
1952 
1953 struct sysctl_oid *
1954 device_get_sysctl_tree(device_t dev)
1955 {
1956 	return (dev->sysctl_tree);
1957 }
1958 
1959 /**
1960  * @brief Print the name of the device followed by a colon and a space
1961  *
1962  * @returns the number of characters printed
1963  */
1964 int
1965 device_print_prettyname(device_t dev)
1966 {
1967 	const char *name = device_get_name(dev);
1968 
1969 	if (name == 0)
1970 		return (printf("unknown: "));
1971 	return (printf("%s%d: ", name, device_get_unit(dev)));
1972 }
1973 
1974 /**
1975  * @brief Print the name of the device followed by a colon, a space
1976  * and the result of calling vprintf() with the value of @p fmt and
1977  * the following arguments.
1978  *
1979  * @returns the number of characters printed
1980  */
1981 int
1982 device_printf(device_t dev, const char * fmt, ...)
1983 {
1984 	va_list ap;
1985 	int retval;
1986 
1987 	retval = device_print_prettyname(dev);
1988 	va_start(ap, fmt);
1989 	retval += vprintf(fmt, ap);
1990 	va_end(ap);
1991 	return (retval);
1992 }
1993 
1994 /**
1995  * @internal
1996  */
1997 static void
1998 device_set_desc_internal(device_t dev, const char* desc, int copy)
1999 {
2000 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2001 		free(dev->desc, M_BUS);
2002 		dev->flags &= ~DF_DESCMALLOCED;
2003 		dev->desc = NULL;
2004 	}
2005 
2006 	if (copy && desc) {
2007 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2008 		if (dev->desc) {
2009 			strcpy(dev->desc, desc);
2010 			dev->flags |= DF_DESCMALLOCED;
2011 		}
2012 	} else {
2013 		/* Avoid a -Wcast-qual warning */
2014 		dev->desc = (char *)(uintptr_t) desc;
2015 	}
2016 
2017 	bus_data_generation_update();
2018 }
2019 
2020 /**
2021  * @brief Set the device's description
2022  *
2023  * The value of @c desc should be a string constant that will not
2024  * change (at least until the description is changed in a subsequent
2025  * call to device_set_desc() or device_set_desc_copy()).
2026  */
2027 void
2028 device_set_desc(device_t dev, const char* desc)
2029 {
2030 	device_set_desc_internal(dev, desc, FALSE);
2031 }
2032 
2033 /**
2034  * @brief Set the device's description
2035  *
2036  * The string pointed to by @c desc is copied. Use this function if
2037  * the device description is generated, (e.g. with sprintf()).
2038  */
2039 void
2040 device_set_desc_copy(device_t dev, const char* desc)
2041 {
2042 	device_set_desc_internal(dev, desc, TRUE);
2043 }
2044 
2045 /**
2046  * @brief Set the device's flags
2047  */
2048 void
2049 device_set_flags(device_t dev, u_int32_t flags)
2050 {
2051 	dev->devflags = flags;
2052 }
2053 
2054 /**
2055  * @brief Return the device's softc field
2056  *
2057  * The softc is allocated and zeroed when a driver is attached, based
2058  * on the size field of the driver.
2059  */
2060 void *
2061 device_get_softc(device_t dev)
2062 {
2063 	return (dev->softc);
2064 }
2065 
2066 /**
2067  * @brief Set the device's softc field
2068  *
2069  * Most drivers do not need to use this since the softc is allocated
2070  * automatically when the driver is attached.
2071  */
2072 void
2073 device_set_softc(device_t dev, void *softc)
2074 {
2075 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2076 		free(dev->softc, M_BUS_SC);
2077 	dev->softc = softc;
2078 	if (dev->softc)
2079 		dev->flags |= DF_EXTERNALSOFTC;
2080 	else
2081 		dev->flags &= ~DF_EXTERNALSOFTC;
2082 }
2083 
2084 /**
2085  * @brief Get the device's ivars field
2086  *
2087  * The ivars field is used by the parent device to store per-device
2088  * state (e.g. the physical location of the device or a list of
2089  * resources).
2090  */
2091 void *
2092 device_get_ivars(device_t dev)
2093 {
2094 
2095 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2096 	return (dev->ivars);
2097 }
2098 
2099 /**
2100  * @brief Set the device's ivars field
2101  */
2102 void
2103 device_set_ivars(device_t dev, void * ivars)
2104 {
2105 
2106 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2107 	dev->ivars = ivars;
2108 }
2109 
2110 /**
2111  * @brief Return the device's state
2112  */
2113 device_state_t
2114 device_get_state(device_t dev)
2115 {
2116 	return (dev->state);
2117 }
2118 
2119 /**
2120  * @brief Set the DF_ENABLED flag for the device
2121  */
2122 void
2123 device_enable(device_t dev)
2124 {
2125 	dev->flags |= DF_ENABLED;
2126 }
2127 
2128 /**
2129  * @brief Clear the DF_ENABLED flag for the device
2130  */
2131 void
2132 device_disable(device_t dev)
2133 {
2134 	dev->flags &= ~DF_ENABLED;
2135 }
2136 
2137 /**
2138  * @brief Increment the busy counter for the device
2139  */
2140 void
2141 device_busy(device_t dev)
2142 {
2143 	if (dev->state < DS_ATTACHED)
2144 		panic("device_busy: called for unattached device");
2145 	if (dev->busy == 0 && dev->parent)
2146 		device_busy(dev->parent);
2147 	dev->busy++;
2148 	dev->state = DS_BUSY;
2149 }
2150 
2151 /**
2152  * @brief Decrement the busy counter for the device
2153  */
2154 void
2155 device_unbusy(device_t dev)
2156 {
2157 	if (dev->state != DS_BUSY)
2158 		panic("device_unbusy: called for non-busy device %s",
2159 		    device_get_nameunit(dev));
2160 	dev->busy--;
2161 	if (dev->busy == 0) {
2162 		if (dev->parent)
2163 			device_unbusy(dev->parent);
2164 		dev->state = DS_ATTACHED;
2165 	}
2166 }
2167 
2168 /**
2169  * @brief Set the DF_QUIET flag for the device
2170  */
2171 void
2172 device_quiet(device_t dev)
2173 {
2174 	dev->flags |= DF_QUIET;
2175 }
2176 
2177 /**
2178  * @brief Clear the DF_QUIET flag for the device
2179  */
2180 void
2181 device_verbose(device_t dev)
2182 {
2183 	dev->flags &= ~DF_QUIET;
2184 }
2185 
2186 /**
2187  * @brief Return non-zero if the DF_QUIET flag is set on the device
2188  */
2189 int
2190 device_is_quiet(device_t dev)
2191 {
2192 	return ((dev->flags & DF_QUIET) != 0);
2193 }
2194 
2195 /**
2196  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2197  */
2198 int
2199 device_is_enabled(device_t dev)
2200 {
2201 	return ((dev->flags & DF_ENABLED) != 0);
2202 }
2203 
2204 /**
2205  * @brief Return non-zero if the device was successfully probed
2206  */
2207 int
2208 device_is_alive(device_t dev)
2209 {
2210 	return (dev->state >= DS_ALIVE);
2211 }
2212 
2213 /**
2214  * @brief Return non-zero if the device currently has a driver
2215  * attached to it
2216  */
2217 int
2218 device_is_attached(device_t dev)
2219 {
2220 	return (dev->state >= DS_ATTACHED);
2221 }
2222 
2223 /**
2224  * @brief Set the devclass of a device
2225  * @see devclass_add_device().
2226  */
2227 int
2228 device_set_devclass(device_t dev, const char *classname)
2229 {
2230 	devclass_t dc;
2231 	int error;
2232 
2233 	if (!classname) {
2234 		if (dev->devclass)
2235 			devclass_delete_device(dev->devclass, dev);
2236 		return (0);
2237 	}
2238 
2239 	if (dev->devclass) {
2240 		printf("device_set_devclass: device class already set\n");
2241 		return (EINVAL);
2242 	}
2243 
2244 	dc = devclass_find_internal(classname, NULL, TRUE);
2245 	if (!dc)
2246 		return (ENOMEM);
2247 
2248 	error = devclass_add_device(dc, dev);
2249 
2250 	bus_data_generation_update();
2251 	return (error);
2252 }
2253 
2254 /**
2255  * @brief Set the driver of a device
2256  *
2257  * @retval 0		success
2258  * @retval EBUSY	the device already has a driver attached
2259  * @retval ENOMEM	a memory allocation failure occurred
2260  */
2261 int
2262 device_set_driver(device_t dev, driver_t *driver)
2263 {
2264 	if (dev->state >= DS_ATTACHED)
2265 		return (EBUSY);
2266 
2267 	if (dev->driver == driver)
2268 		return (0);
2269 
2270 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2271 		free(dev->softc, M_BUS_SC);
2272 		dev->softc = NULL;
2273 	}
2274 	kobj_delete((kobj_t) dev, NULL);
2275 	dev->driver = driver;
2276 	if (driver) {
2277 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2278 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2279 			dev->softc = malloc(driver->size, M_BUS_SC,
2280 			    M_NOWAIT | M_ZERO);
2281 			if (!dev->softc) {
2282 				kobj_delete((kobj_t) dev, NULL);
2283 				kobj_init((kobj_t) dev, &null_class);
2284 				dev->driver = NULL;
2285 				return (ENOMEM);
2286 			}
2287 		}
2288 	} else {
2289 		kobj_init((kobj_t) dev, &null_class);
2290 	}
2291 
2292 	bus_data_generation_update();
2293 	return (0);
2294 }
2295 
2296 /**
2297  * @brief Probe a device and attach a driver if possible
2298  *
2299  * This function is the core of the device autoconfiguration
2300  * system. Its purpose is to select a suitable driver for a device and
2301  * then call that driver to initialise the hardware appropriately. The
2302  * driver is selected by calling the DEVICE_PROBE() method of a set of
2303  * candidate drivers and then choosing the driver which returned the
2304  * best value. This driver is then attached to the device using
2305  * device_attach().
2306  *
2307  * The set of suitable drivers is taken from the list of drivers in
2308  * the parent device's devclass. If the device was originally created
2309  * with a specific class name (see device_add_child()), only drivers
2310  * with that name are probed, otherwise all drivers in the devclass
2311  * are probed. If no drivers return successful probe values in the
2312  * parent devclass, the search continues in the parent of that
2313  * devclass (see devclass_get_parent()) if any.
2314  *
2315  * @param dev		the device to initialise
2316  *
2317  * @retval 0		success
2318  * @retval ENXIO	no driver was found
2319  * @retval ENOMEM	memory allocation failure
2320  * @retval non-zero	some other unix error code
2321  */
2322 int
2323 device_probe_and_attach(device_t dev)
2324 {
2325 	int error;
2326 
2327 	GIANT_REQUIRED;
2328 
2329 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2330 		return (0);
2331 
2332 	if (!(dev->flags & DF_ENABLED)) {
2333 		if (bootverbose && device_get_name(dev) != NULL) {
2334 			device_print_prettyname(dev);
2335 			printf("not probed (disabled)\n");
2336 		}
2337 		return (0);
2338 	}
2339 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2340 		if (!(dev->flags & DF_DONENOMATCH)) {
2341 			BUS_PROBE_NOMATCH(dev->parent, dev);
2342 			devnomatch(dev);
2343 			dev->flags |= DF_DONENOMATCH;
2344 		}
2345 		return (error);
2346 	}
2347 	error = device_attach(dev);
2348 
2349 	return (error);
2350 }
2351 
2352 /**
2353  * @brief Attach a device driver to a device
2354  *
2355  * This function is a wrapper around the DEVICE_ATTACH() driver
2356  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2357  * device's sysctl tree, optionally prints a description of the device
2358  * and queues a notification event for user-based device management
2359  * services.
2360  *
2361  * Normally this function is only called internally from
2362  * device_probe_and_attach().
2363  *
2364  * @param dev		the device to initialise
2365  *
2366  * @retval 0		success
2367  * @retval ENXIO	no driver was found
2368  * @retval ENOMEM	memory allocation failure
2369  * @retval non-zero	some other unix error code
2370  */
2371 int
2372 device_attach(device_t dev)
2373 {
2374 	int error;
2375 
2376 	device_sysctl_init(dev);
2377 	if (!device_is_quiet(dev))
2378 		device_print_child(dev->parent, dev);
2379 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2380 		printf("device_attach: %s%d attach returned %d\n",
2381 		    dev->driver->name, dev->unit, error);
2382 		/* Unset the class; set in device_probe_child */
2383 		if (dev->devclass == NULL)
2384 			device_set_devclass(dev, NULL);
2385 		device_set_driver(dev, NULL);
2386 		device_sysctl_fini(dev);
2387 		dev->state = DS_NOTPRESENT;
2388 		return (error);
2389 	}
2390 	dev->state = DS_ATTACHED;
2391 	devadded(dev);
2392 	return (0);
2393 }
2394 
2395 /**
2396  * @brief Detach a driver from a device
2397  *
2398  * This function is a wrapper around the DEVICE_DETACH() driver
2399  * method. If the call to DEVICE_DETACH() succeeds, it calls
2400  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
2401  * notification event for user-based device management services and
2402  * cleans up the device's sysctl tree.
2403  *
2404  * @param dev		the device to un-initialise
2405  *
2406  * @retval 0		success
2407  * @retval ENXIO	no driver was found
2408  * @retval ENOMEM	memory allocation failure
2409  * @retval non-zero	some other unix error code
2410  */
2411 int
2412 device_detach(device_t dev)
2413 {
2414 	int error;
2415 
2416 	GIANT_REQUIRED;
2417 
2418 	PDEBUG(("%s", DEVICENAME(dev)));
2419 	if (dev->state == DS_BUSY)
2420 		return (EBUSY);
2421 	if (dev->state != DS_ATTACHED)
2422 		return (0);
2423 
2424 	if ((error = DEVICE_DETACH(dev)) != 0)
2425 		return (error);
2426 	devremoved(dev);
2427 	device_printf(dev, "detached\n");
2428 	if (dev->parent)
2429 		BUS_CHILD_DETACHED(dev->parent, dev);
2430 
2431 	if (!(dev->flags & DF_FIXEDCLASS))
2432 		devclass_delete_device(dev->devclass, dev);
2433 
2434 	dev->state = DS_NOTPRESENT;
2435 	device_set_driver(dev, NULL);
2436 	device_set_desc(dev, NULL);
2437 	device_sysctl_fini(dev);
2438 
2439 	return (0);
2440 }
2441 
2442 /**
2443  * @brief Tells a driver to quiesce itself.
2444  *
2445  * This function is a wrapper around the DEVICE_QUIESCE() driver
2446  * method. If the call to DEVICE_QUIESCE() succeeds.
2447  *
2448  * @param dev		the device to quiesce
2449  *
2450  * @retval 0		success
2451  * @retval ENXIO	no driver was found
2452  * @retval ENOMEM	memory allocation failure
2453  * @retval non-zero	some other unix error code
2454  */
2455 int
2456 device_quiesce(device_t dev)
2457 {
2458 
2459 	PDEBUG(("%s", DEVICENAME(dev)));
2460 	if (dev->state == DS_BUSY)
2461 		return (EBUSY);
2462 	if (dev->state != DS_ATTACHED)
2463 		return (0);
2464 
2465 	return (DEVICE_QUIESCE(dev));
2466 }
2467 
2468 /**
2469  * @brief Notify a device of system shutdown
2470  *
2471  * This function calls the DEVICE_SHUTDOWN() driver method if the
2472  * device currently has an attached driver.
2473  *
2474  * @returns the value returned by DEVICE_SHUTDOWN()
2475  */
2476 int
2477 device_shutdown(device_t dev)
2478 {
2479 	if (dev->state < DS_ATTACHED)
2480 		return (0);
2481 	return (DEVICE_SHUTDOWN(dev));
2482 }
2483 
2484 /**
2485  * @brief Set the unit number of a device
2486  *
2487  * This function can be used to override the unit number used for a
2488  * device (e.g. to wire a device to a pre-configured unit number).
2489  */
2490 int
2491 device_set_unit(device_t dev, int unit)
2492 {
2493 	devclass_t dc;
2494 	int err;
2495 
2496 	dc = device_get_devclass(dev);
2497 	if (unit < dc->maxunit && dc->devices[unit])
2498 		return (EBUSY);
2499 	err = devclass_delete_device(dc, dev);
2500 	if (err)
2501 		return (err);
2502 	dev->unit = unit;
2503 	err = devclass_add_device(dc, dev);
2504 	if (err)
2505 		return (err);
2506 
2507 	bus_data_generation_update();
2508 	return (0);
2509 }
2510 
2511 /*======================================*/
2512 /*
2513  * Some useful method implementations to make life easier for bus drivers.
2514  */
2515 
2516 /**
2517  * @brief Initialise a resource list.
2518  *
2519  * @param rl		the resource list to initialise
2520  */
2521 void
2522 resource_list_init(struct resource_list *rl)
2523 {
2524 	STAILQ_INIT(rl);
2525 }
2526 
2527 /**
2528  * @brief Reclaim memory used by a resource list.
2529  *
2530  * This function frees the memory for all resource entries on the list
2531  * (if any).
2532  *
2533  * @param rl		the resource list to free
2534  */
2535 void
2536 resource_list_free(struct resource_list *rl)
2537 {
2538 	struct resource_list_entry *rle;
2539 
2540 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2541 		if (rle->res)
2542 			panic("resource_list_free: resource entry is busy");
2543 		STAILQ_REMOVE_HEAD(rl, link);
2544 		free(rle, M_BUS);
2545 	}
2546 }
2547 
2548 /**
2549  * @brief Add a resource entry.
2550  *
2551  * This function adds a resource entry using the given @p type, @p
2552  * start, @p end and @p count values. A rid value is chosen by
2553  * searching sequentially for the first unused rid starting at zero.
2554  *
2555  * @param rl		the resource list to edit
2556  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2557  * @param start		the start address of the resource
2558  * @param end		the end address of the resource
2559  * @param count		XXX end-start+1
2560  */
2561 int
2562 resource_list_add_next(struct resource_list *rl, int type, u_long start,
2563     u_long end, u_long count)
2564 {
2565 	int rid;
2566 
2567 	rid = 0;
2568 	while (resource_list_find(rl, type, rid) != NULL)
2569 		rid++;
2570 	resource_list_add(rl, type, rid, start, end, count);
2571 	return (rid);
2572 }
2573 
2574 /**
2575  * @brief Add or modify a resource entry.
2576  *
2577  * If an existing entry exists with the same type and rid, it will be
2578  * modified using the given values of @p start, @p end and @p
2579  * count. If no entry exists, a new one will be created using the
2580  * given values.  The resource list entry that matches is then returned.
2581  *
2582  * @param rl		the resource list to edit
2583  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2584  * @param rid		the resource identifier
2585  * @param start		the start address of the resource
2586  * @param end		the end address of the resource
2587  * @param count		XXX end-start+1
2588  */
2589 struct resource_list_entry *
2590 resource_list_add(struct resource_list *rl, int type, int rid,
2591     u_long start, u_long end, u_long count)
2592 {
2593 	struct resource_list_entry *rle;
2594 
2595 	rle = resource_list_find(rl, type, rid);
2596 	if (!rle) {
2597 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
2598 		    M_NOWAIT);
2599 		if (!rle)
2600 			panic("resource_list_add: can't record entry");
2601 		STAILQ_INSERT_TAIL(rl, rle, link);
2602 		rle->type = type;
2603 		rle->rid = rid;
2604 		rle->res = NULL;
2605 	}
2606 
2607 	if (rle->res)
2608 		panic("resource_list_add: resource entry is busy");
2609 
2610 	rle->start = start;
2611 	rle->end = end;
2612 	rle->count = count;
2613 	return (rle);
2614 }
2615 
2616 /**
2617  * @brief Find a resource entry by type and rid.
2618  *
2619  * @param rl		the resource list to search
2620  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2621  * @param rid		the resource identifier
2622  *
2623  * @returns the resource entry pointer or NULL if there is no such
2624  * entry.
2625  */
2626 struct resource_list_entry *
2627 resource_list_find(struct resource_list *rl, int type, int rid)
2628 {
2629 	struct resource_list_entry *rle;
2630 
2631 	STAILQ_FOREACH(rle, rl, link) {
2632 		if (rle->type == type && rle->rid == rid)
2633 			return (rle);
2634 	}
2635 	return (NULL);
2636 }
2637 
2638 /**
2639  * @brief Delete a resource entry.
2640  *
2641  * @param rl		the resource list to edit
2642  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2643  * @param rid		the resource identifier
2644  */
2645 void
2646 resource_list_delete(struct resource_list *rl, int type, int rid)
2647 {
2648 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
2649 
2650 	if (rle) {
2651 		if (rle->res != NULL)
2652 			panic("resource_list_delete: resource has not been released");
2653 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
2654 		free(rle, M_BUS);
2655 	}
2656 }
2657 
2658 /**
2659  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
2660  *
2661  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
2662  * and passing the allocation up to the parent of @p bus. This assumes
2663  * that the first entry of @c device_get_ivars(child) is a struct
2664  * resource_list. This also handles 'passthrough' allocations where a
2665  * child is a remote descendant of bus by passing the allocation up to
2666  * the parent of bus.
2667  *
2668  * Typically, a bus driver would store a list of child resources
2669  * somewhere in the child device's ivars (see device_get_ivars()) and
2670  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
2671  * then call resource_list_alloc() to perform the allocation.
2672  *
2673  * @param rl		the resource list to allocate from
2674  * @param bus		the parent device of @p child
2675  * @param child		the device which is requesting an allocation
2676  * @param type		the type of resource to allocate
2677  * @param rid		a pointer to the resource identifier
2678  * @param start		hint at the start of the resource range - pass
2679  *			@c 0UL for any start address
2680  * @param end		hint at the end of the resource range - pass
2681  *			@c ~0UL for any end address
2682  * @param count		hint at the size of range required - pass @c 1
2683  *			for any size
2684  * @param flags		any extra flags to control the resource
2685  *			allocation - see @c RF_XXX flags in
2686  *			<sys/rman.h> for details
2687  *
2688  * @returns		the resource which was allocated or @c NULL if no
2689  *			resource could be allocated
2690  */
2691 struct resource *
2692 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
2693     int type, int *rid, u_long start, u_long end, u_long count, u_int flags)
2694 {
2695 	struct resource_list_entry *rle = NULL;
2696 	int passthrough = (device_get_parent(child) != bus);
2697 	int isdefault = (start == 0UL && end == ~0UL);
2698 
2699 	if (passthrough) {
2700 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2701 		    type, rid, start, end, count, flags));
2702 	}
2703 
2704 	rle = resource_list_find(rl, type, *rid);
2705 
2706 	if (!rle)
2707 		return (NULL);		/* no resource of that type/rid */
2708 
2709 	if (rle->res)
2710 		panic("resource_list_alloc: resource entry is busy");
2711 
2712 	if (isdefault) {
2713 		start = rle->start;
2714 		count = ulmax(count, rle->count);
2715 		end = ulmax(rle->end, start + count - 1);
2716 	}
2717 
2718 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2719 	    type, rid, start, end, count, flags);
2720 
2721 	/*
2722 	 * Record the new range.
2723 	 */
2724 	if (rle->res) {
2725 		rle->start = rman_get_start(rle->res);
2726 		rle->end = rman_get_end(rle->res);
2727 		rle->count = count;
2728 	}
2729 
2730 	return (rle->res);
2731 }
2732 
2733 /**
2734  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
2735  *
2736  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
2737  * used with resource_list_alloc().
2738  *
2739  * @param rl		the resource list which was allocated from
2740  * @param bus		the parent device of @p child
2741  * @param child		the device which is requesting a release
2742  * @param type		the type of resource to allocate
2743  * @param rid		the resource identifier
2744  * @param res		the resource to release
2745  *
2746  * @retval 0		success
2747  * @retval non-zero	a standard unix error code indicating what
2748  *			error condition prevented the operation
2749  */
2750 int
2751 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
2752     int type, int rid, struct resource *res)
2753 {
2754 	struct resource_list_entry *rle = NULL;
2755 	int passthrough = (device_get_parent(child) != bus);
2756 	int error;
2757 
2758 	if (passthrough) {
2759 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2760 		    type, rid, res));
2761 	}
2762 
2763 	rle = resource_list_find(rl, type, rid);
2764 
2765 	if (!rle)
2766 		panic("resource_list_release: can't find resource");
2767 	if (!rle->res)
2768 		panic("resource_list_release: resource entry is not busy");
2769 
2770 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2771 	    type, rid, res);
2772 	if (error)
2773 		return (error);
2774 
2775 	rle->res = NULL;
2776 	return (0);
2777 }
2778 
2779 /**
2780  * @brief Print a description of resources in a resource list
2781  *
2782  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
2783  * The name is printed if at least one resource of the given type is available.
2784  * The format is used to print resource start and end.
2785  *
2786  * @param rl		the resource list to print
2787  * @param name		the name of @p type, e.g. @c "memory"
2788  * @param type		type type of resource entry to print
2789  * @param format	printf(9) format string to print resource
2790  *			start and end values
2791  *
2792  * @returns		the number of characters printed
2793  */
2794 int
2795 resource_list_print_type(struct resource_list *rl, const char *name, int type,
2796     const char *format)
2797 {
2798 	struct resource_list_entry *rle;
2799 	int printed, retval;
2800 
2801 	printed = 0;
2802 	retval = 0;
2803 	/* Yes, this is kinda cheating */
2804 	STAILQ_FOREACH(rle, rl, link) {
2805 		if (rle->type == type) {
2806 			if (printed == 0)
2807 				retval += printf(" %s ", name);
2808 			else
2809 				retval += printf(",");
2810 			printed++;
2811 			retval += printf(format, rle->start);
2812 			if (rle->count > 1) {
2813 				retval += printf("-");
2814 				retval += printf(format, rle->start +
2815 						 rle->count - 1);
2816 			}
2817 		}
2818 	}
2819 	return (retval);
2820 }
2821 
2822 /**
2823  * @brief Releases all the resources in a list.
2824  *
2825  * @param rl		The resource list to purge.
2826  *
2827  * @returns		nothing
2828  */
2829 void
2830 resource_list_purge(struct resource_list *rl)
2831 {
2832 	struct resource_list_entry *rle;
2833 
2834 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2835 		if (rle->res)
2836 			bus_release_resource(rman_get_device(rle->res),
2837 			    rle->type, rle->rid, rle->res);
2838 		STAILQ_REMOVE_HEAD(rl, link);
2839 		free(rle, M_BUS);
2840 	}
2841 }
2842 
2843 device_t
2844 bus_generic_add_child(device_t dev, int order, const char *name, int unit)
2845 {
2846 
2847 	return (device_add_child_ordered(dev, order, name, unit));
2848 }
2849 
2850 /**
2851  * @brief Helper function for implementing DEVICE_PROBE()
2852  *
2853  * This function can be used to help implement the DEVICE_PROBE() for
2854  * a bus (i.e. a device which has other devices attached to it). It
2855  * calls the DEVICE_IDENTIFY() method of each driver in the device's
2856  * devclass.
2857  */
2858 int
2859 bus_generic_probe(device_t dev)
2860 {
2861 	devclass_t dc = dev->devclass;
2862 	driverlink_t dl;
2863 
2864 	TAILQ_FOREACH(dl, &dc->drivers, link) {
2865 		DEVICE_IDENTIFY(dl->driver, dev);
2866 	}
2867 
2868 	return (0);
2869 }
2870 
2871 /**
2872  * @brief Helper function for implementing DEVICE_ATTACH()
2873  *
2874  * This function can be used to help implement the DEVICE_ATTACH() for
2875  * a bus. It calls device_probe_and_attach() for each of the device's
2876  * children.
2877  */
2878 int
2879 bus_generic_attach(device_t dev)
2880 {
2881 	device_t child;
2882 
2883 	TAILQ_FOREACH(child, &dev->children, link) {
2884 		device_probe_and_attach(child);
2885 	}
2886 
2887 	return (0);
2888 }
2889 
2890 /**
2891  * @brief Helper function for implementing DEVICE_DETACH()
2892  *
2893  * This function can be used to help implement the DEVICE_DETACH() for
2894  * a bus. It calls device_detach() for each of the device's
2895  * children.
2896  */
2897 int
2898 bus_generic_detach(device_t dev)
2899 {
2900 	device_t child;
2901 	int error;
2902 
2903 	if (dev->state != DS_ATTACHED)
2904 		return (EBUSY);
2905 
2906 	TAILQ_FOREACH(child, &dev->children, link) {
2907 		if ((error = device_detach(child)) != 0)
2908 			return (error);
2909 	}
2910 
2911 	return (0);
2912 }
2913 
2914 /**
2915  * @brief Helper function for implementing DEVICE_SHUTDOWN()
2916  *
2917  * This function can be used to help implement the DEVICE_SHUTDOWN()
2918  * for a bus. It calls device_shutdown() for each of the device's
2919  * children.
2920  */
2921 int
2922 bus_generic_shutdown(device_t dev)
2923 {
2924 	device_t child;
2925 
2926 	TAILQ_FOREACH(child, &dev->children, link) {
2927 		device_shutdown(child);
2928 	}
2929 
2930 	return (0);
2931 }
2932 
2933 /**
2934  * @brief Helper function for implementing DEVICE_SUSPEND()
2935  *
2936  * This function can be used to help implement the DEVICE_SUSPEND()
2937  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
2938  * children. If any call to DEVICE_SUSPEND() fails, the suspend
2939  * operation is aborted and any devices which were suspended are
2940  * resumed immediately by calling their DEVICE_RESUME() methods.
2941  */
2942 int
2943 bus_generic_suspend(device_t dev)
2944 {
2945 	int		error;
2946 	device_t	child, child2;
2947 
2948 	TAILQ_FOREACH(child, &dev->children, link) {
2949 		error = DEVICE_SUSPEND(child);
2950 		if (error) {
2951 			for (child2 = TAILQ_FIRST(&dev->children);
2952 			     child2 && child2 != child;
2953 			     child2 = TAILQ_NEXT(child2, link))
2954 				DEVICE_RESUME(child2);
2955 			return (error);
2956 		}
2957 	}
2958 	return (0);
2959 }
2960 
2961 /**
2962  * @brief Helper function for implementing DEVICE_RESUME()
2963  *
2964  * This function can be used to help implement the DEVICE_RESUME() for
2965  * a bus. It calls DEVICE_RESUME() on each of the device's children.
2966  */
2967 int
2968 bus_generic_resume(device_t dev)
2969 {
2970 	device_t	child;
2971 
2972 	TAILQ_FOREACH(child, &dev->children, link) {
2973 		DEVICE_RESUME(child);
2974 		/* if resume fails, there's nothing we can usefully do... */
2975 	}
2976 	return (0);
2977 }
2978 
2979 /**
2980  * @brief Helper function for implementing BUS_PRINT_CHILD().
2981  *
2982  * This function prints the first part of the ascii representation of
2983  * @p child, including its name, unit and description (if any - see
2984  * device_set_desc()).
2985  *
2986  * @returns the number of characters printed
2987  */
2988 int
2989 bus_print_child_header(device_t dev, device_t child)
2990 {
2991 	int	retval = 0;
2992 
2993 	if (device_get_desc(child)) {
2994 		retval += device_printf(child, "<%s>", device_get_desc(child));
2995 	} else {
2996 		retval += printf("%s", device_get_nameunit(child));
2997 	}
2998 
2999 	return (retval);
3000 }
3001 
3002 /**
3003  * @brief Helper function for implementing BUS_PRINT_CHILD().
3004  *
3005  * This function prints the last part of the ascii representation of
3006  * @p child, which consists of the string @c " on " followed by the
3007  * name and unit of the @p dev.
3008  *
3009  * @returns the number of characters printed
3010  */
3011 int
3012 bus_print_child_footer(device_t dev, device_t child)
3013 {
3014 	return (printf(" on %s\n", device_get_nameunit(dev)));
3015 }
3016 
3017 /**
3018  * @brief Helper function for implementing BUS_PRINT_CHILD().
3019  *
3020  * This function simply calls bus_print_child_header() followed by
3021  * bus_print_child_footer().
3022  *
3023  * @returns the number of characters printed
3024  */
3025 int
3026 bus_generic_print_child(device_t dev, device_t child)
3027 {
3028 	int	retval = 0;
3029 
3030 	retval += bus_print_child_header(dev, child);
3031 	retval += bus_print_child_footer(dev, child);
3032 
3033 	return (retval);
3034 }
3035 
3036 /**
3037  * @brief Stub function for implementing BUS_READ_IVAR().
3038  *
3039  * @returns ENOENT
3040  */
3041 int
3042 bus_generic_read_ivar(device_t dev, device_t child, int index,
3043     uintptr_t * result)
3044 {
3045 	return (ENOENT);
3046 }
3047 
3048 /**
3049  * @brief Stub function for implementing BUS_WRITE_IVAR().
3050  *
3051  * @returns ENOENT
3052  */
3053 int
3054 bus_generic_write_ivar(device_t dev, device_t child, int index,
3055     uintptr_t value)
3056 {
3057 	return (ENOENT);
3058 }
3059 
3060 /**
3061  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
3062  *
3063  * @returns NULL
3064  */
3065 struct resource_list *
3066 bus_generic_get_resource_list(device_t dev, device_t child)
3067 {
3068 	return (NULL);
3069 }
3070 
3071 /**
3072  * @brief Helper function for implementing BUS_DRIVER_ADDED().
3073  *
3074  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
3075  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
3076  * and then calls device_probe_and_attach() for each unattached child.
3077  */
3078 void
3079 bus_generic_driver_added(device_t dev, driver_t *driver)
3080 {
3081 	device_t child;
3082 
3083 	DEVICE_IDENTIFY(driver, dev);
3084 	TAILQ_FOREACH(child, &dev->children, link) {
3085 		if (child->state == DS_NOTPRESENT ||
3086 		    (child->flags & DF_REBID))
3087 			device_probe_and_attach(child);
3088 	}
3089 }
3090 
3091 /**
3092  * @brief Helper function for implementing BUS_SETUP_INTR().
3093  *
3094  * This simple implementation of BUS_SETUP_INTR() simply calls the
3095  * BUS_SETUP_INTR() method of the parent of @p dev.
3096  */
3097 int
3098 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
3099     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
3100     void **cookiep)
3101 {
3102 	/* Propagate up the bus hierarchy until someone handles it. */
3103 	if (dev->parent)
3104 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
3105 		    filter, intr, arg, cookiep));
3106 	return (EINVAL);
3107 }
3108 
3109 /**
3110  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
3111  *
3112  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
3113  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
3114  */
3115 int
3116 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
3117     void *cookie)
3118 {
3119 	/* Propagate up the bus hierarchy until someone handles it. */
3120 	if (dev->parent)
3121 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
3122 	return (EINVAL);
3123 }
3124 
3125 /**
3126  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3127  *
3128  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
3129  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
3130  */
3131 struct resource *
3132 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
3133     u_long start, u_long end, u_long count, u_int flags)
3134 {
3135 	/* Propagate up the bus hierarchy until someone handles it. */
3136 	if (dev->parent)
3137 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
3138 		    start, end, count, flags));
3139 	return (NULL);
3140 }
3141 
3142 /**
3143  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3144  *
3145  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
3146  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
3147  */
3148 int
3149 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
3150     struct resource *r)
3151 {
3152 	/* Propagate up the bus hierarchy until someone handles it. */
3153 	if (dev->parent)
3154 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
3155 		    r));
3156 	return (EINVAL);
3157 }
3158 
3159 /**
3160  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
3161  *
3162  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
3163  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
3164  */
3165 int
3166 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
3167     struct resource *r)
3168 {
3169 	/* Propagate up the bus hierarchy until someone handles it. */
3170 	if (dev->parent)
3171 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
3172 		    r));
3173 	return (EINVAL);
3174 }
3175 
3176 /**
3177  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
3178  *
3179  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
3180  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
3181  */
3182 int
3183 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
3184     int rid, struct resource *r)
3185 {
3186 	/* Propagate up the bus hierarchy until someone handles it. */
3187 	if (dev->parent)
3188 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
3189 		    r));
3190 	return (EINVAL);
3191 }
3192 
3193 /**
3194  * @brief Helper function for implementing BUS_CONFIG_INTR().
3195  *
3196  * This simple implementation of BUS_CONFIG_INTR() simply calls the
3197  * BUS_CONFIG_INTR() method of the parent of @p dev.
3198  */
3199 int
3200 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
3201     enum intr_polarity pol)
3202 {
3203 
3204 	/* Propagate up the bus hierarchy until someone handles it. */
3205 	if (dev->parent)
3206 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
3207 	return (EINVAL);
3208 }
3209 
3210 /**
3211  * @brief Helper function for implementing BUS_GET_DMA_TAG().
3212  *
3213  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
3214  * BUS_GET_DMA_TAG() method of the parent of @p dev.
3215  */
3216 bus_dma_tag_t
3217 bus_generic_get_dma_tag(device_t dev, device_t child)
3218 {
3219 
3220 	/* Propagate up the bus hierarchy until someone handles it. */
3221 	if (dev->parent != NULL)
3222 		return (BUS_GET_DMA_TAG(dev->parent, child));
3223 	return (NULL);
3224 }
3225 
3226 /**
3227  * @brief Helper function for implementing BUS_GET_RESOURCE().
3228  *
3229  * This implementation of BUS_GET_RESOURCE() uses the
3230  * resource_list_find() function to do most of the work. It calls
3231  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3232  * search.
3233  */
3234 int
3235 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
3236     u_long *startp, u_long *countp)
3237 {
3238 	struct resource_list *		rl = NULL;
3239 	struct resource_list_entry *	rle = NULL;
3240 
3241 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3242 	if (!rl)
3243 		return (EINVAL);
3244 
3245 	rle = resource_list_find(rl, type, rid);
3246 	if (!rle)
3247 		return (ENOENT);
3248 
3249 	if (startp)
3250 		*startp = rle->start;
3251 	if (countp)
3252 		*countp = rle->count;
3253 
3254 	return (0);
3255 }
3256 
3257 /**
3258  * @brief Helper function for implementing BUS_SET_RESOURCE().
3259  *
3260  * This implementation of BUS_SET_RESOURCE() uses the
3261  * resource_list_add() function to do most of the work. It calls
3262  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3263  * edit.
3264  */
3265 int
3266 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
3267     u_long start, u_long count)
3268 {
3269 	struct resource_list *		rl = NULL;
3270 
3271 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3272 	if (!rl)
3273 		return (EINVAL);
3274 
3275 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
3276 
3277 	return (0);
3278 }
3279 
3280 /**
3281  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
3282  *
3283  * This implementation of BUS_DELETE_RESOURCE() uses the
3284  * resource_list_delete() 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 void
3289 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
3290 {
3291 	struct resource_list *		rl = NULL;
3292 
3293 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3294 	if (!rl)
3295 		return;
3296 
3297 	resource_list_delete(rl, type, rid);
3298 
3299 	return;
3300 }
3301 
3302 /**
3303  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3304  *
3305  * This implementation of BUS_RELEASE_RESOURCE() uses the
3306  * resource_list_release() function to do most of the work. It calls
3307  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3308  */
3309 int
3310 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
3311     int rid, struct resource *r)
3312 {
3313 	struct resource_list *		rl = NULL;
3314 
3315 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3316 	if (!rl)
3317 		return (EINVAL);
3318 
3319 	return (resource_list_release(rl, dev, child, type, rid, r));
3320 }
3321 
3322 /**
3323  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3324  *
3325  * This implementation of BUS_ALLOC_RESOURCE() uses the
3326  * resource_list_alloc() function to do most of the work. It calls
3327  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3328  */
3329 struct resource *
3330 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
3331     int *rid, u_long start, u_long end, u_long count, u_int flags)
3332 {
3333 	struct resource_list *		rl = NULL;
3334 
3335 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3336 	if (!rl)
3337 		return (NULL);
3338 
3339 	return (resource_list_alloc(rl, dev, child, type, rid,
3340 	    start, end, count, flags));
3341 }
3342 
3343 /**
3344  * @brief Helper function for implementing BUS_CHILD_PRESENT().
3345  *
3346  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
3347  * BUS_CHILD_PRESENT() method of the parent of @p dev.
3348  */
3349 int
3350 bus_generic_child_present(device_t dev, device_t child)
3351 {
3352 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
3353 }
3354 
3355 /*
3356  * Some convenience functions to make it easier for drivers to use the
3357  * resource-management functions.  All these really do is hide the
3358  * indirection through the parent's method table, making for slightly
3359  * less-wordy code.  In the future, it might make sense for this code
3360  * to maintain some sort of a list of resources allocated by each device.
3361  */
3362 
3363 int
3364 bus_alloc_resources(device_t dev, struct resource_spec *rs,
3365     struct resource **res)
3366 {
3367 	int i;
3368 
3369 	for (i = 0; rs[i].type != -1; i++)
3370 		res[i] = NULL;
3371 	for (i = 0; rs[i].type != -1; i++) {
3372 		res[i] = bus_alloc_resource_any(dev,
3373 		    rs[i].type, &rs[i].rid, rs[i].flags);
3374 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
3375 			bus_release_resources(dev, rs, res);
3376 			return (ENXIO);
3377 		}
3378 	}
3379 	return (0);
3380 }
3381 
3382 void
3383 bus_release_resources(device_t dev, const struct resource_spec *rs,
3384     struct resource **res)
3385 {
3386 	int i;
3387 
3388 	for (i = 0; rs[i].type != -1; i++)
3389 		if (res[i] != NULL) {
3390 			bus_release_resource(
3391 			    dev, rs[i].type, rs[i].rid, res[i]);
3392 			res[i] = NULL;
3393 		}
3394 }
3395 
3396 /**
3397  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
3398  *
3399  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
3400  * parent of @p dev.
3401  */
3402 struct resource *
3403 bus_alloc_resource(device_t dev, int type, int *rid, u_long start, u_long end,
3404     u_long count, u_int flags)
3405 {
3406 	if (dev->parent == NULL)
3407 		return (NULL);
3408 	return (BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
3409 	    count, flags));
3410 }
3411 
3412 /**
3413  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
3414  *
3415  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
3416  * parent of @p dev.
3417  */
3418 int
3419 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
3420 {
3421 	if (dev->parent == NULL)
3422 		return (EINVAL);
3423 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3424 }
3425 
3426 /**
3427  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
3428  *
3429  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
3430  * parent of @p dev.
3431  */
3432 int
3433 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
3434 {
3435 	if (dev->parent == NULL)
3436 		return (EINVAL);
3437 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3438 }
3439 
3440 /**
3441  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
3442  *
3443  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
3444  * parent of @p dev.
3445  */
3446 int
3447 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
3448 {
3449 	if (dev->parent == NULL)
3450 		return (EINVAL);
3451 	return (BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r));
3452 }
3453 
3454 /**
3455  * @brief Wrapper function for BUS_SETUP_INTR().
3456  *
3457  * This function simply calls the BUS_SETUP_INTR() method of the
3458  * parent of @p dev.
3459  */
3460 int
3461 bus_setup_intr(device_t dev, struct resource *r, int flags,
3462     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
3463 {
3464 	int error;
3465 
3466 	if (dev->parent != NULL) {
3467 		if ((flags &~ INTR_ENTROPY) == (INTR_TYPE_NET | INTR_MPSAFE) &&
3468 		    !debug_mpsafenet)
3469 			flags &= ~INTR_MPSAFE;
3470 		error = BUS_SETUP_INTR(dev->parent, dev, r, flags,
3471 		    filter, handler, arg, cookiep);
3472 		if (error == 0) {
3473 			if (handler != NULL && !(flags & INTR_MPSAFE))
3474 				device_printf(dev, "[GIANT-LOCKED]\n");
3475 			if (bootverbose && (flags & INTR_MPSAFE))
3476 				device_printf(dev, "[MPSAFE]\n");
3477 			if (filter != NULL) {
3478 				if (handler == NULL)
3479 					device_printf(dev, "[FILTER]\n");
3480 				else
3481 					device_printf(dev, "[FILTER+ITHREAD]\n");
3482 			} else
3483 				device_printf(dev, "[ITHREAD]\n");
3484 		}
3485 	} else
3486 		error = EINVAL;
3487 	return (error);
3488 }
3489 
3490 /**
3491  * @brief Wrapper function for BUS_TEARDOWN_INTR().
3492  *
3493  * This function simply calls the BUS_TEARDOWN_INTR() method of the
3494  * parent of @p dev.
3495  */
3496 int
3497 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
3498 {
3499 	if (dev->parent == NULL)
3500 		return (EINVAL);
3501 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
3502 }
3503 
3504 /**
3505  * @brief Wrapper function for BUS_SET_RESOURCE().
3506  *
3507  * This function simply calls the BUS_SET_RESOURCE() method of the
3508  * parent of @p dev.
3509  */
3510 int
3511 bus_set_resource(device_t dev, int type, int rid,
3512     u_long start, u_long count)
3513 {
3514 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
3515 	    start, count));
3516 }
3517 
3518 /**
3519  * @brief Wrapper function for BUS_GET_RESOURCE().
3520  *
3521  * This function simply calls the BUS_GET_RESOURCE() method of the
3522  * parent of @p dev.
3523  */
3524 int
3525 bus_get_resource(device_t dev, int type, int rid,
3526     u_long *startp, u_long *countp)
3527 {
3528 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3529 	    startp, countp));
3530 }
3531 
3532 /**
3533  * @brief Wrapper function for BUS_GET_RESOURCE().
3534  *
3535  * This function simply calls the BUS_GET_RESOURCE() method of the
3536  * parent of @p dev and returns the start value.
3537  */
3538 u_long
3539 bus_get_resource_start(device_t dev, int type, int rid)
3540 {
3541 	u_long start, count;
3542 	int error;
3543 
3544 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3545 	    &start, &count);
3546 	if (error)
3547 		return (0);
3548 	return (start);
3549 }
3550 
3551 /**
3552  * @brief Wrapper function for BUS_GET_RESOURCE().
3553  *
3554  * This function simply calls the BUS_GET_RESOURCE() method of the
3555  * parent of @p dev and returns the count value.
3556  */
3557 u_long
3558 bus_get_resource_count(device_t dev, int type, int rid)
3559 {
3560 	u_long start, count;
3561 	int error;
3562 
3563 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3564 	    &start, &count);
3565 	if (error)
3566 		return (0);
3567 	return (count);
3568 }
3569 
3570 /**
3571  * @brief Wrapper function for BUS_DELETE_RESOURCE().
3572  *
3573  * This function simply calls the BUS_DELETE_RESOURCE() method of the
3574  * parent of @p dev.
3575  */
3576 void
3577 bus_delete_resource(device_t dev, int type, int rid)
3578 {
3579 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
3580 }
3581 
3582 /**
3583  * @brief Wrapper function for BUS_CHILD_PRESENT().
3584  *
3585  * This function simply calls the BUS_CHILD_PRESENT() method of the
3586  * parent of @p dev.
3587  */
3588 int
3589 bus_child_present(device_t child)
3590 {
3591 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
3592 }
3593 
3594 /**
3595  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
3596  *
3597  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
3598  * parent of @p dev.
3599  */
3600 int
3601 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
3602 {
3603 	device_t parent;
3604 
3605 	parent = device_get_parent(child);
3606 	if (parent == NULL) {
3607 		*buf = '\0';
3608 		return (0);
3609 	}
3610 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
3611 }
3612 
3613 /**
3614  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
3615  *
3616  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
3617  * parent of @p dev.
3618  */
3619 int
3620 bus_child_location_str(device_t child, char *buf, size_t buflen)
3621 {
3622 	device_t parent;
3623 
3624 	parent = device_get_parent(child);
3625 	if (parent == NULL) {
3626 		*buf = '\0';
3627 		return (0);
3628 	}
3629 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
3630 }
3631 
3632 /**
3633  * @brief Wrapper function for BUS_GET_DMA_TAG().
3634  *
3635  * This function simply calls the BUS_GET_DMA_TAG() method of the
3636  * parent of @p dev.
3637  */
3638 bus_dma_tag_t
3639 bus_get_dma_tag(device_t dev)
3640 {
3641 	device_t parent;
3642 
3643 	parent = device_get_parent(dev);
3644 	if (parent == NULL)
3645 		return (NULL);
3646 	return (BUS_GET_DMA_TAG(parent, dev));
3647 }
3648 
3649 /* Resume all devices and then notify userland that we're up again. */
3650 static int
3651 root_resume(device_t dev)
3652 {
3653 	int error;
3654 
3655 	error = bus_generic_resume(dev);
3656 	if (error == 0)
3657 		devctl_notify("kern", "power", "resume", NULL);
3658 	return (error);
3659 }
3660 
3661 static int
3662 root_print_child(device_t dev, device_t child)
3663 {
3664 	int	retval = 0;
3665 
3666 	retval += bus_print_child_header(dev, child);
3667 	retval += printf("\n");
3668 
3669 	return (retval);
3670 }
3671 
3672 static int
3673 root_setup_intr(device_t dev, device_t child, driver_intr_t *intr, void *arg,
3674     void **cookiep)
3675 {
3676 	/*
3677 	 * If an interrupt mapping gets to here something bad has happened.
3678 	 */
3679 	panic("root_setup_intr");
3680 }
3681 
3682 /*
3683  * If we get here, assume that the device is permanant and really is
3684  * present in the system.  Removable bus drivers are expected to intercept
3685  * this call long before it gets here.  We return -1 so that drivers that
3686  * really care can check vs -1 or some ERRNO returned higher in the food
3687  * chain.
3688  */
3689 static int
3690 root_child_present(device_t dev, device_t child)
3691 {
3692 	return (-1);
3693 }
3694 
3695 static kobj_method_t root_methods[] = {
3696 	/* Device interface */
3697 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
3698 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
3699 	KOBJMETHOD(device_resume,	root_resume),
3700 
3701 	/* Bus interface */
3702 	KOBJMETHOD(bus_print_child,	root_print_child),
3703 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
3704 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
3705 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
3706 	KOBJMETHOD(bus_child_present,	root_child_present),
3707 
3708 	{ 0, 0 }
3709 };
3710 
3711 static driver_t root_driver = {
3712 	"root",
3713 	root_methods,
3714 	1,			/* no softc */
3715 };
3716 
3717 device_t	root_bus;
3718 devclass_t	root_devclass;
3719 
3720 static int
3721 root_bus_module_handler(module_t mod, int what, void* arg)
3722 {
3723 	switch (what) {
3724 	case MOD_LOAD:
3725 		TAILQ_INIT(&bus_data_devices);
3726 		kobj_class_compile((kobj_class_t) &root_driver);
3727 		root_bus = make_device(NULL, "root", 0);
3728 		root_bus->desc = "System root bus";
3729 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
3730 		root_bus->driver = &root_driver;
3731 		root_bus->state = DS_ATTACHED;
3732 		root_devclass = devclass_find_internal("root", NULL, FALSE);
3733 		devinit();
3734 		return (0);
3735 
3736 	case MOD_SHUTDOWN:
3737 		device_shutdown(root_bus);
3738 		return (0);
3739 	default:
3740 		return (EOPNOTSUPP);
3741 	}
3742 
3743 	return (0);
3744 }
3745 
3746 static moduledata_t root_bus_mod = {
3747 	"rootbus",
3748 	root_bus_module_handler,
3749 	0
3750 };
3751 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
3752 
3753 /**
3754  * @brief Automatically configure devices
3755  *
3756  * This function begins the autoconfiguration process by calling
3757  * device_probe_and_attach() for each child of the @c root0 device.
3758  */
3759 void
3760 root_bus_configure(void)
3761 {
3762 	device_t dev;
3763 
3764 	PDEBUG(("."));
3765 
3766 	TAILQ_FOREACH(dev, &root_bus->children, link) {
3767 		device_probe_and_attach(dev);
3768 	}
3769 }
3770 
3771 /**
3772  * @brief Module handler for registering device drivers
3773  *
3774  * This module handler is used to automatically register device
3775  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
3776  * devclass_add_driver() for the driver described by the
3777  * driver_module_data structure pointed to by @p arg
3778  */
3779 int
3780 driver_module_handler(module_t mod, int what, void *arg)
3781 {
3782 	int error;
3783 	struct driver_module_data *dmd;
3784 	devclass_t bus_devclass;
3785 	kobj_class_t driver;
3786 
3787 	dmd = (struct driver_module_data *)arg;
3788 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
3789 	error = 0;
3790 
3791 	switch (what) {
3792 	case MOD_LOAD:
3793 		if (dmd->dmd_chainevh)
3794 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3795 
3796 		driver = dmd->dmd_driver;
3797 		PDEBUG(("Loading module: driver %s on bus %s",
3798 		    DRIVERNAME(driver), dmd->dmd_busname));
3799 		error = devclass_add_driver(bus_devclass, driver);
3800 		if (error)
3801 			break;
3802 
3803 		/*
3804 		 * If the driver has any base classes, make the
3805 		 * devclass inherit from the devclass of the driver's
3806 		 * first base class. This will allow the system to
3807 		 * search for drivers in both devclasses for children
3808 		 * of a device using this driver.
3809 		 */
3810 		if (driver->baseclasses) {
3811 			const char *parentname;
3812 			parentname = driver->baseclasses[0]->name;
3813 			*dmd->dmd_devclass =
3814 				devclass_find_internal(driver->name,
3815 				    parentname, TRUE);
3816 		} else {
3817 			*dmd->dmd_devclass =
3818 				devclass_find_internal(driver->name, NULL, TRUE);
3819 		}
3820 		break;
3821 
3822 	case MOD_UNLOAD:
3823 		PDEBUG(("Unloading module: driver %s from bus %s",
3824 		    DRIVERNAME(dmd->dmd_driver),
3825 		    dmd->dmd_busname));
3826 		error = devclass_delete_driver(bus_devclass,
3827 		    dmd->dmd_driver);
3828 
3829 		if (!error && dmd->dmd_chainevh)
3830 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3831 		break;
3832 	case MOD_QUIESCE:
3833 		PDEBUG(("Quiesce module: driver %s from bus %s",
3834 		    DRIVERNAME(dmd->dmd_driver),
3835 		    dmd->dmd_busname));
3836 		error = devclass_quiesce_driver(bus_devclass,
3837 		    dmd->dmd_driver);
3838 
3839 		if (!error && dmd->dmd_chainevh)
3840 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3841 		break;
3842 	default:
3843 		error = EOPNOTSUPP;
3844 		break;
3845 	}
3846 
3847 	return (error);
3848 }
3849 
3850 /**
3851  * @brief Enumerate all hinted devices for this bus.
3852  *
3853  * Walks throught he hints for this bus and calls the bus_hinted_child
3854  * routine for each one it fines.  It searches first for the specific
3855  * bus that's being probed for hinted children (eg isa0), and then for
3856  * generic children (eg isa).
3857  *
3858  * @param	dev	bus device to enumerate
3859  */
3860 void
3861 bus_enumerate_hinted_children(device_t bus)
3862 {
3863 	int i;
3864 	const char *dname, *busname;
3865 	int dunit;
3866 
3867 	/*
3868 	 * enumerate all devices on the specific bus
3869 	 */
3870 	busname = device_get_nameunit(bus);
3871 	i = 0;
3872 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3873 		BUS_HINTED_CHILD(bus, dname, dunit);
3874 
3875 	/*
3876 	 * and all the generic ones.
3877 	 */
3878 	busname = device_get_name(bus);
3879 	i = 0;
3880 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3881 		BUS_HINTED_CHILD(bus, dname, dunit);
3882 }
3883 
3884 #ifdef BUS_DEBUG
3885 
3886 /* the _short versions avoid iteration by not calling anything that prints
3887  * more than oneliners. I love oneliners.
3888  */
3889 
3890 static void
3891 print_device_short(device_t dev, int indent)
3892 {
3893 	if (!dev)
3894 		return;
3895 
3896 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
3897 	    dev->unit, dev->desc,
3898 	    (dev->parent? "":"no "),
3899 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
3900 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
3901 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
3902 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
3903 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
3904 	    (dev->flags&DF_REBID? "rebiddable,":""),
3905 	    (dev->ivars? "":"no "),
3906 	    (dev->softc? "":"no "),
3907 	    dev->busy));
3908 }
3909 
3910 static void
3911 print_device(device_t dev, int indent)
3912 {
3913 	if (!dev)
3914 		return;
3915 
3916 	print_device_short(dev, indent);
3917 
3918 	indentprintf(("Parent:\n"));
3919 	print_device_short(dev->parent, indent+1);
3920 	indentprintf(("Driver:\n"));
3921 	print_driver_short(dev->driver, indent+1);
3922 	indentprintf(("Devclass:\n"));
3923 	print_devclass_short(dev->devclass, indent+1);
3924 }
3925 
3926 void
3927 print_device_tree_short(device_t dev, int indent)
3928 /* print the device and all its children (indented) */
3929 {
3930 	device_t child;
3931 
3932 	if (!dev)
3933 		return;
3934 
3935 	print_device_short(dev, indent);
3936 
3937 	TAILQ_FOREACH(child, &dev->children, link) {
3938 		print_device_tree_short(child, indent+1);
3939 	}
3940 }
3941 
3942 void
3943 print_device_tree(device_t dev, int indent)
3944 /* print the device and all its children (indented) */
3945 {
3946 	device_t child;
3947 
3948 	if (!dev)
3949 		return;
3950 
3951 	print_device(dev, indent);
3952 
3953 	TAILQ_FOREACH(child, &dev->children, link) {
3954 		print_device_tree(child, indent+1);
3955 	}
3956 }
3957 
3958 static void
3959 print_driver_short(driver_t *driver, int indent)
3960 {
3961 	if (!driver)
3962 		return;
3963 
3964 	indentprintf(("driver %s: softc size = %zd\n",
3965 	    driver->name, driver->size));
3966 }
3967 
3968 static void
3969 print_driver(driver_t *driver, int indent)
3970 {
3971 	if (!driver)
3972 		return;
3973 
3974 	print_driver_short(driver, indent);
3975 }
3976 
3977 
3978 static void
3979 print_driver_list(driver_list_t drivers, int indent)
3980 {
3981 	driverlink_t driver;
3982 
3983 	TAILQ_FOREACH(driver, &drivers, link) {
3984 		print_driver(driver->driver, indent);
3985 	}
3986 }
3987 
3988 static void
3989 print_devclass_short(devclass_t dc, int indent)
3990 {
3991 	if ( !dc )
3992 		return;
3993 
3994 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
3995 }
3996 
3997 static void
3998 print_devclass(devclass_t dc, int indent)
3999 {
4000 	int i;
4001 
4002 	if ( !dc )
4003 		return;
4004 
4005 	print_devclass_short(dc, indent);
4006 	indentprintf(("Drivers:\n"));
4007 	print_driver_list(dc->drivers, indent+1);
4008 
4009 	indentprintf(("Devices:\n"));
4010 	for (i = 0; i < dc->maxunit; i++)
4011 		if (dc->devices[i])
4012 			print_device(dc->devices[i], indent+1);
4013 }
4014 
4015 void
4016 print_devclass_list_short(void)
4017 {
4018 	devclass_t dc;
4019 
4020 	printf("Short listing of devclasses, drivers & devices:\n");
4021 	TAILQ_FOREACH(dc, &devclasses, link) {
4022 		print_devclass_short(dc, 0);
4023 	}
4024 }
4025 
4026 void
4027 print_devclass_list(void)
4028 {
4029 	devclass_t dc;
4030 
4031 	printf("Full listing of devclasses, drivers & devices:\n");
4032 	TAILQ_FOREACH(dc, &devclasses, link) {
4033 		print_devclass(dc, 0);
4034 	}
4035 }
4036 
4037 #endif
4038 
4039 /*
4040  * User-space access to the device tree.
4041  *
4042  * We implement a small set of nodes:
4043  *
4044  * hw.bus			Single integer read method to obtain the
4045  *				current generation count.
4046  * hw.bus.devices		Reads the entire device tree in flat space.
4047  * hw.bus.rman			Resource manager interface
4048  *
4049  * We might like to add the ability to scan devclasses and/or drivers to
4050  * determine what else is currently loaded/available.
4051  */
4052 
4053 static int
4054 sysctl_bus(SYSCTL_HANDLER_ARGS)
4055 {
4056 	struct u_businfo	ubus;
4057 
4058 	ubus.ub_version = BUS_USER_VERSION;
4059 	ubus.ub_generation = bus_data_generation;
4060 
4061 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
4062 }
4063 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
4064     "bus-related data");
4065 
4066 static int
4067 sysctl_devices(SYSCTL_HANDLER_ARGS)
4068 {
4069 	int			*name = (int *)arg1;
4070 	u_int			namelen = arg2;
4071 	int			index;
4072 	struct device		*dev;
4073 	struct u_device		udev;	/* XXX this is a bit big */
4074 	int			error;
4075 
4076 	if (namelen != 2)
4077 		return (EINVAL);
4078 
4079 	if (bus_data_generation_check(name[0]))
4080 		return (EINVAL);
4081 
4082 	index = name[1];
4083 
4084 	/*
4085 	 * Scan the list of devices, looking for the requested index.
4086 	 */
4087 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
4088 		if (index-- == 0)
4089 			break;
4090 	}
4091 	if (dev == NULL)
4092 		return (ENOENT);
4093 
4094 	/*
4095 	 * Populate the return array.
4096 	 */
4097 	bzero(&udev, sizeof(udev));
4098 	udev.dv_handle = (uintptr_t)dev;
4099 	udev.dv_parent = (uintptr_t)dev->parent;
4100 	if (dev->nameunit != NULL)
4101 		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
4102 	if (dev->desc != NULL)
4103 		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
4104 	if (dev->driver != NULL && dev->driver->name != NULL)
4105 		strlcpy(udev.dv_drivername, dev->driver->name,
4106 		    sizeof(udev.dv_drivername));
4107 	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
4108 	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
4109 	udev.dv_devflags = dev->devflags;
4110 	udev.dv_flags = dev->flags;
4111 	udev.dv_state = dev->state;
4112 	error = SYSCTL_OUT(req, &udev, sizeof(udev));
4113 	return (error);
4114 }
4115 
4116 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
4117     "system device tree");
4118 
4119 int
4120 bus_data_generation_check(int generation)
4121 {
4122 	if (generation != bus_data_generation)
4123 		return (1);
4124 
4125 	/* XXX generate optimised lists here? */
4126 	return (0);
4127 }
4128 
4129 void
4130 bus_data_generation_update(void)
4131 {
4132 	bus_data_generation++;
4133 }
4134 
4135 int
4136 bus_free_resource(device_t dev, int type, struct resource *r)
4137 {
4138 	if (r == NULL)
4139 		return (0);
4140 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
4141 }
4142