xref: /freebsd/sys/kern/subr_bus.c (revision 54ebdd631db8c0bba2baab0155f603a8b5cf014a)
1 /*-
2  * Copyright (c) 1997,1998,2003 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_bus.h"
31 
32 #include <sys/param.h>
33 #include <sys/conf.h>
34 #include <sys/filio.h>
35 #include <sys/lock.h>
36 #include <sys/kernel.h>
37 #include <sys/kobj.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/poll.h>
42 #include <sys/proc.h>
43 #include <sys/condvar.h>
44 #include <sys/queue.h>
45 #include <machine/bus.h>
46 #include <sys/rman.h>
47 #include <sys/selinfo.h>
48 #include <sys/signalvar.h>
49 #include <sys/sysctl.h>
50 #include <sys/systm.h>
51 #include <sys/uio.h>
52 #include <sys/bus.h>
53 #include <sys/interrupt.h>
54 
55 #include <machine/stdarg.h>
56 
57 #include <vm/uma.h>
58 
59 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW, NULL, NULL);
60 SYSCTL_NODE(, OID_AUTO, dev, CTLFLAG_RW, NULL, NULL);
61 
62 /*
63  * Used to attach drivers to devclasses.
64  */
65 typedef struct driverlink *driverlink_t;
66 struct driverlink {
67 	kobj_class_t	driver;
68 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
69 };
70 
71 /*
72  * Forward declarations
73  */
74 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
75 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
76 typedef TAILQ_HEAD(device_list, device) device_list_t;
77 
78 struct devclass {
79 	TAILQ_ENTRY(devclass) link;
80 	devclass_t	parent;		/* parent in devclass hierarchy */
81 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
82 	char		*name;
83 	device_t	*devices;	/* array of devices indexed by unit */
84 	int		maxunit;	/* size of devices array */
85 
86 	struct sysctl_ctx_list sysctl_ctx;
87 	struct sysctl_oid *sysctl_tree;
88 };
89 
90 /**
91  * @brief Implementation of device.
92  */
93 struct device {
94 	/*
95 	 * A device is a kernel object. The first field must be the
96 	 * current ops table for the object.
97 	 */
98 	KOBJ_FIELDS;
99 
100 	/*
101 	 * Device hierarchy.
102 	 */
103 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
104 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
105 	device_t	parent;		/**< parent of this device  */
106 	device_list_t	children;	/**< list of child devices */
107 
108 	/*
109 	 * Details of this device.
110 	 */
111 	driver_t	*driver;	/**< current driver */
112 	devclass_t	devclass;	/**< current device class */
113 	int		unit;		/**< current unit number */
114 	char*		nameunit;	/**< name+unit e.g. foodev0 */
115 	char*		desc;		/**< driver specific description */
116 	int		busy;		/**< count of calls to device_busy() */
117 	device_state_t	state;		/**< current device state  */
118 	u_int32_t	devflags;	/**< api level flags for device_get_flags() */
119 	u_short		flags;		/**< internal device flags  */
120 #define	DF_ENABLED	1		/* device should be probed/attached */
121 #define	DF_FIXEDCLASS	2		/* devclass specified at create time */
122 #define	DF_WILDCARD	4		/* unit was originally wildcard */
123 #define	DF_DESCMALLOCED	8		/* description was malloced */
124 #define	DF_QUIET	16		/* don't print verbose attach message */
125 #define	DF_DONENOMATCH	32		/* don't execute DEVICE_NOMATCH again */
126 #define	DF_EXTERNALSOFTC 64		/* softc not allocated by us */
127 #define	DF_REBID	128		/* Can rebid after attach */
128 	u_char	order;			/**< order from device_add_child_ordered() */
129 	u_char	pad;
130 	void	*ivars;			/**< instance variables  */
131 	void	*softc;			/**< current driver's variables  */
132 
133 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
134 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
135 };
136 
137 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
138 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
139 
140 #ifdef BUS_DEBUG
141 
142 static int bus_debug = 1;
143 TUNABLE_INT("bus.debug", &bus_debug);
144 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RW, &bus_debug, 0,
145     "Debug bus code");
146 
147 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
148 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
149 #define DRIVERNAME(d)	((d)? d->name : "no driver")
150 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
151 
152 /**
153  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
154  * prevent syslog from deleting initial spaces
155  */
156 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
157 
158 static void print_device_short(device_t dev, int indent);
159 static void print_device(device_t dev, int indent);
160 void print_device_tree_short(device_t dev, int indent);
161 void print_device_tree(device_t dev, int indent);
162 static void print_driver_short(driver_t *driver, int indent);
163 static void print_driver(driver_t *driver, int indent);
164 static void print_driver_list(driver_list_t drivers, int indent);
165 static void print_devclass_short(devclass_t dc, int indent);
166 static void print_devclass(devclass_t dc, int indent);
167 void print_devclass_list_short(void);
168 void print_devclass_list(void);
169 
170 #else
171 /* Make the compiler ignore the function calls */
172 #define PDEBUG(a)			/* nop */
173 #define DEVICENAME(d)			/* nop */
174 #define DRIVERNAME(d)			/* nop */
175 #define DEVCLANAME(d)			/* nop */
176 
177 #define print_device_short(d,i)		/* nop */
178 #define print_device(d,i)		/* nop */
179 #define print_device_tree_short(d,i)	/* nop */
180 #define print_device_tree(d,i)		/* nop */
181 #define print_driver_short(d,i)		/* nop */
182 #define print_driver(d,i)		/* nop */
183 #define print_driver_list(d,i)		/* nop */
184 #define print_devclass_short(d,i)	/* nop */
185 #define print_devclass(d,i)		/* nop */
186 #define print_devclass_list_short()	/* nop */
187 #define print_devclass_list()		/* nop */
188 #endif
189 
190 /*
191  * dev sysctl tree
192  */
193 
194 enum {
195 	DEVCLASS_SYSCTL_PARENT,
196 };
197 
198 static int
199 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
200 {
201 	devclass_t dc = (devclass_t)arg1;
202 	const char *value;
203 
204 	switch (arg2) {
205 	case DEVCLASS_SYSCTL_PARENT:
206 		value = dc->parent ? dc->parent->name : "";
207 		break;
208 	default:
209 		return (EINVAL);
210 	}
211 	return (SYSCTL_OUT(req, value, strlen(value)));
212 }
213 
214 static void
215 devclass_sysctl_init(devclass_t dc)
216 {
217 
218 	if (dc->sysctl_tree != NULL)
219 		return;
220 	sysctl_ctx_init(&dc->sysctl_ctx);
221 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
222 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
223 	    CTLFLAG_RD, 0, "");
224 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
225 	    OID_AUTO, "%parent", CTLFLAG_RD,
226 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
227 	    "parent class");
228 }
229 
230 enum {
231 	DEVICE_SYSCTL_DESC,
232 	DEVICE_SYSCTL_DRIVER,
233 	DEVICE_SYSCTL_LOCATION,
234 	DEVICE_SYSCTL_PNPINFO,
235 	DEVICE_SYSCTL_PARENT,
236 };
237 
238 static int
239 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
240 {
241 	device_t dev = (device_t)arg1;
242 	const char *value;
243 	char *buf;
244 	int error;
245 
246 	buf = NULL;
247 	switch (arg2) {
248 	case DEVICE_SYSCTL_DESC:
249 		value = dev->desc ? dev->desc : "";
250 		break;
251 	case DEVICE_SYSCTL_DRIVER:
252 		value = dev->driver ? dev->driver->name : "";
253 		break;
254 	case DEVICE_SYSCTL_LOCATION:
255 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
256 		bus_child_location_str(dev, buf, 1024);
257 		break;
258 	case DEVICE_SYSCTL_PNPINFO:
259 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
260 		bus_child_pnpinfo_str(dev, buf, 1024);
261 		break;
262 	case DEVICE_SYSCTL_PARENT:
263 		value = dev->parent ? dev->parent->nameunit : "";
264 		break;
265 	default:
266 		return (EINVAL);
267 	}
268 	error = SYSCTL_OUT(req, value, strlen(value));
269 	if (buf != NULL)
270 		free(buf, M_BUS);
271 	return (error);
272 }
273 
274 static void
275 device_sysctl_init(device_t dev)
276 {
277 	devclass_t dc = dev->devclass;
278 
279 	if (dev->sysctl_tree != NULL)
280 		return;
281 	devclass_sysctl_init(dc);
282 	sysctl_ctx_init(&dev->sysctl_ctx);
283 	dev->sysctl_tree = SYSCTL_ADD_NODE(&dev->sysctl_ctx,
284 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
285 	    dev->nameunit + strlen(dc->name),
286 	    CTLFLAG_RD, 0, "");
287 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
288 	    OID_AUTO, "%desc", CTLFLAG_RD,
289 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
290 	    "device description");
291 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
292 	    OID_AUTO, "%driver", CTLFLAG_RD,
293 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
294 	    "device driver name");
295 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
296 	    OID_AUTO, "%location", CTLFLAG_RD,
297 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
298 	    "device location relative to parent");
299 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
300 	    OID_AUTO, "%pnpinfo", CTLFLAG_RD,
301 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
302 	    "device identification");
303 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
304 	    OID_AUTO, "%parent", CTLFLAG_RD,
305 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
306 	    "parent device");
307 }
308 
309 static void
310 device_sysctl_update(device_t dev)
311 {
312 	devclass_t dc = dev->devclass;
313 
314 	if (dev->sysctl_tree == NULL)
315 		return;
316 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
317 }
318 
319 static void
320 device_sysctl_fini(device_t dev)
321 {
322 	if (dev->sysctl_tree == NULL)
323 		return;
324 	sysctl_ctx_free(&dev->sysctl_ctx);
325 	dev->sysctl_tree = NULL;
326 }
327 
328 /*
329  * /dev/devctl implementation
330  */
331 
332 /*
333  * This design allows only one reader for /dev/devctl.  This is not desirable
334  * in the long run, but will get a lot of hair out of this implementation.
335  * Maybe we should make this device a clonable device.
336  *
337  * Also note: we specifically do not attach a device to the device_t tree
338  * to avoid potential chicken and egg problems.  One could argue that all
339  * of this belongs to the root node.  One could also further argue that the
340  * sysctl interface that we have not might more properly be an ioctl
341  * interface, but at this stage of the game, I'm not inclined to rock that
342  * boat.
343  *
344  * I'm also not sure that the SIGIO support is done correctly or not, as
345  * I copied it from a driver that had SIGIO support that likely hasn't been
346  * tested since 3.4 or 2.2.8!
347  */
348 
349 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
350 static int devctl_disable = 0;
351 TUNABLE_INT("hw.bus.devctl_disable", &devctl_disable);
352 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RW, 0, 0,
353     sysctl_devctl_disable, "I", "devctl disable");
354 
355 static d_open_t		devopen;
356 static d_close_t	devclose;
357 static d_read_t		devread;
358 static d_ioctl_t	devioctl;
359 static d_poll_t		devpoll;
360 
361 static struct cdevsw dev_cdevsw = {
362 	.d_version =	D_VERSION,
363 	.d_flags =	D_NEEDGIANT,
364 	.d_open =	devopen,
365 	.d_close =	devclose,
366 	.d_read =	devread,
367 	.d_ioctl =	devioctl,
368 	.d_poll =	devpoll,
369 	.d_name =	"devctl",
370 };
371 
372 struct dev_event_info
373 {
374 	char *dei_data;
375 	TAILQ_ENTRY(dev_event_info) dei_link;
376 };
377 
378 TAILQ_HEAD(devq, dev_event_info);
379 
380 static struct dev_softc
381 {
382 	int	inuse;
383 	int	nonblock;
384 	struct mtx mtx;
385 	struct cv cv;
386 	struct selinfo sel;
387 	struct devq devq;
388 	struct proc *async_proc;
389 } devsoftc;
390 
391 static struct cdev *devctl_dev;
392 
393 static void
394 devinit(void)
395 {
396 	devctl_dev = make_dev(&dev_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
397 	    "devctl");
398 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
399 	cv_init(&devsoftc.cv, "dev cv");
400 	TAILQ_INIT(&devsoftc.devq);
401 }
402 
403 static int
404 devopen(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
405 {
406 	if (devsoftc.inuse)
407 		return (EBUSY);
408 	/* move to init */
409 	devsoftc.inuse = 1;
410 	devsoftc.nonblock = 0;
411 	devsoftc.async_proc = NULL;
412 	return (0);
413 }
414 
415 static int
416 devclose(struct cdev *dev, int fflag, int devtype, d_thread_t *td)
417 {
418 	devsoftc.inuse = 0;
419 	mtx_lock(&devsoftc.mtx);
420 	cv_broadcast(&devsoftc.cv);
421 	mtx_unlock(&devsoftc.mtx);
422 
423 	return (0);
424 }
425 
426 /*
427  * The read channel for this device is used to report changes to
428  * userland in realtime.  We are required to free the data as well as
429  * the n1 object because we allocate them separately.  Also note that
430  * we return one record at a time.  If you try to read this device a
431  * character at a time, you will lose the rest of the data.  Listening
432  * programs are expected to cope.
433  */
434 static int
435 devread(struct cdev *dev, struct uio *uio, int ioflag)
436 {
437 	struct dev_event_info *n1;
438 	int rv;
439 
440 	mtx_lock(&devsoftc.mtx);
441 	while (TAILQ_EMPTY(&devsoftc.devq)) {
442 		if (devsoftc.nonblock) {
443 			mtx_unlock(&devsoftc.mtx);
444 			return (EAGAIN);
445 		}
446 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
447 		if (rv) {
448 			/*
449 			 * Need to translate ERESTART to EINTR here? -- jake
450 			 */
451 			mtx_unlock(&devsoftc.mtx);
452 			return (rv);
453 		}
454 	}
455 	n1 = TAILQ_FIRST(&devsoftc.devq);
456 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
457 	mtx_unlock(&devsoftc.mtx);
458 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
459 	free(n1->dei_data, M_BUS);
460 	free(n1, M_BUS);
461 	return (rv);
462 }
463 
464 static	int
465 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, d_thread_t *td)
466 {
467 	switch (cmd) {
468 
469 	case FIONBIO:
470 		if (*(int*)data)
471 			devsoftc.nonblock = 1;
472 		else
473 			devsoftc.nonblock = 0;
474 		return (0);
475 	case FIOASYNC:
476 		if (*(int*)data)
477 			devsoftc.async_proc = td->td_proc;
478 		else
479 			devsoftc.async_proc = NULL;
480 		return (0);
481 
482 		/* (un)Support for other fcntl() calls. */
483 	case FIOCLEX:
484 	case FIONCLEX:
485 	case FIONREAD:
486 	case FIOSETOWN:
487 	case FIOGETOWN:
488 	default:
489 		break;
490 	}
491 	return (ENOTTY);
492 }
493 
494 static	int
495 devpoll(struct cdev *dev, int events, d_thread_t *td)
496 {
497 	int	revents = 0;
498 
499 	mtx_lock(&devsoftc.mtx);
500 	if (events & (POLLIN | POLLRDNORM)) {
501 		if (!TAILQ_EMPTY(&devsoftc.devq))
502 			revents = events & (POLLIN | POLLRDNORM);
503 		else
504 			selrecord(td, &devsoftc.sel);
505 	}
506 	mtx_unlock(&devsoftc.mtx);
507 
508 	return (revents);
509 }
510 
511 /**
512  * @brief Return whether the userland process is running
513  */
514 boolean_t
515 devctl_process_running(void)
516 {
517 	return (devsoftc.inuse == 1);
518 }
519 
520 /**
521  * @brief Queue data to be read from the devctl device
522  *
523  * Generic interface to queue data to the devctl device.  It is
524  * assumed that @p data is properly formatted.  It is further assumed
525  * that @p data is allocated using the M_BUS malloc type.
526  */
527 void
528 devctl_queue_data(char *data)
529 {
530 	struct dev_event_info *n1 = NULL;
531 	struct proc *p;
532 
533 	n1 = malloc(sizeof(*n1), M_BUS, M_NOWAIT);
534 	if (n1 == NULL)
535 		return;
536 	n1->dei_data = data;
537 	mtx_lock(&devsoftc.mtx);
538 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
539 	cv_broadcast(&devsoftc.cv);
540 	mtx_unlock(&devsoftc.mtx);
541 	selwakeup(&devsoftc.sel);
542 	p = devsoftc.async_proc;
543 	if (p != NULL) {
544 		PROC_LOCK(p);
545 		psignal(p, SIGIO);
546 		PROC_UNLOCK(p);
547 	}
548 }
549 
550 /**
551  * @brief Send a 'notification' to userland, using standard ways
552  */
553 void
554 devctl_notify(const char *system, const char *subsystem, const char *type,
555     const char *data)
556 {
557 	int len = 0;
558 	char *msg;
559 
560 	if (system == NULL)
561 		return;		/* BOGUS!  Must specify system. */
562 	if (subsystem == NULL)
563 		return;		/* BOGUS!  Must specify subsystem. */
564 	if (type == NULL)
565 		return;		/* BOGUS!  Must specify type. */
566 	len += strlen(" system=") + strlen(system);
567 	len += strlen(" subsystem=") + strlen(subsystem);
568 	len += strlen(" type=") + strlen(type);
569 	/* add in the data message plus newline. */
570 	if (data != NULL)
571 		len += strlen(data);
572 	len += 3;	/* '!', '\n', and NUL */
573 	msg = malloc(len, M_BUS, M_NOWAIT);
574 	if (msg == NULL)
575 		return;		/* Drop it on the floor */
576 	if (data != NULL)
577 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
578 		    system, subsystem, type, data);
579 	else
580 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
581 		    system, subsystem, type);
582 	devctl_queue_data(msg);
583 }
584 
585 /*
586  * Common routine that tries to make sending messages as easy as possible.
587  * We allocate memory for the data, copy strings into that, but do not
588  * free it unless there's an error.  The dequeue part of the driver should
589  * free the data.  We don't send data when the device is disabled.  We do
590  * send data, even when we have no listeners, because we wish to avoid
591  * races relating to startup and restart of listening applications.
592  *
593  * devaddq is designed to string together the type of event, with the
594  * object of that event, plus the plug and play info and location info
595  * for that event.  This is likely most useful for devices, but less
596  * useful for other consumers of this interface.  Those should use
597  * the devctl_queue_data() interface instead.
598  */
599 static void
600 devaddq(const char *type, const char *what, device_t dev)
601 {
602 	char *data = NULL;
603 	char *loc = NULL;
604 	char *pnp = NULL;
605 	const char *parstr;
606 
607 	if (devctl_disable)
608 		return;
609 	data = malloc(1024, M_BUS, M_NOWAIT);
610 	if (data == NULL)
611 		goto bad;
612 
613 	/* get the bus specific location of this device */
614 	loc = malloc(1024, M_BUS, M_NOWAIT);
615 	if (loc == NULL)
616 		goto bad;
617 	*loc = '\0';
618 	bus_child_location_str(dev, loc, 1024);
619 
620 	/* Get the bus specific pnp info of this device */
621 	pnp = malloc(1024, M_BUS, M_NOWAIT);
622 	if (pnp == NULL)
623 		goto bad;
624 	*pnp = '\0';
625 	bus_child_pnpinfo_str(dev, pnp, 1024);
626 
627 	/* Get the parent of this device, or / if high enough in the tree. */
628 	if (device_get_parent(dev) == NULL)
629 		parstr = ".";	/* Or '/' ? */
630 	else
631 		parstr = device_get_nameunit(device_get_parent(dev));
632 	/* String it all together. */
633 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
634 	  parstr);
635 	free(loc, M_BUS);
636 	free(pnp, M_BUS);
637 	devctl_queue_data(data);
638 	return;
639 bad:
640 	free(pnp, M_BUS);
641 	free(loc, M_BUS);
642 	free(data, M_BUS);
643 	return;
644 }
645 
646 /*
647  * A device was added to the tree.  We are called just after it successfully
648  * attaches (that is, probe and attach success for this device).  No call
649  * is made if a device is merely parented into the tree.  See devnomatch
650  * if probe fails.  If attach fails, no notification is sent (but maybe
651  * we should have a different message for this).
652  */
653 static void
654 devadded(device_t dev)
655 {
656 	char *pnp = NULL;
657 	char *tmp = NULL;
658 
659 	pnp = malloc(1024, M_BUS, M_NOWAIT);
660 	if (pnp == NULL)
661 		goto fail;
662 	tmp = malloc(1024, M_BUS, M_NOWAIT);
663 	if (tmp == NULL)
664 		goto fail;
665 	*pnp = '\0';
666 	bus_child_pnpinfo_str(dev, pnp, 1024);
667 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
668 	devaddq("+", tmp, dev);
669 fail:
670 	if (pnp != NULL)
671 		free(pnp, M_BUS);
672 	if (tmp != NULL)
673 		free(tmp, M_BUS);
674 	return;
675 }
676 
677 /*
678  * A device was removed from the tree.  We are called just before this
679  * happens.
680  */
681 static void
682 devremoved(device_t dev)
683 {
684 	char *pnp = NULL;
685 	char *tmp = NULL;
686 
687 	pnp = malloc(1024, M_BUS, M_NOWAIT);
688 	if (pnp == NULL)
689 		goto fail;
690 	tmp = malloc(1024, M_BUS, M_NOWAIT);
691 	if (tmp == NULL)
692 		goto fail;
693 	*pnp = '\0';
694 	bus_child_pnpinfo_str(dev, pnp, 1024);
695 	snprintf(tmp, 1024, "%s %s", device_get_nameunit(dev), pnp);
696 	devaddq("-", tmp, dev);
697 fail:
698 	if (pnp != NULL)
699 		free(pnp, M_BUS);
700 	if (tmp != NULL)
701 		free(tmp, M_BUS);
702 	return;
703 }
704 
705 /*
706  * Called when there's no match for this device.  This is only called
707  * the first time that no match happens, so we don't keep getitng this
708  * message.  Should that prove to be undesirable, we can change it.
709  * This is called when all drivers that can attach to a given bus
710  * decline to accept this device.  Other errrors may not be detected.
711  */
712 static void
713 devnomatch(device_t dev)
714 {
715 	devaddq("?", "", dev);
716 }
717 
718 static int
719 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
720 {
721 	struct dev_event_info *n1;
722 	int dis, error;
723 
724 	dis = devctl_disable;
725 	error = sysctl_handle_int(oidp, &dis, 0, req);
726 	if (error || !req->newptr)
727 		return (error);
728 	mtx_lock(&devsoftc.mtx);
729 	devctl_disable = dis;
730 	if (dis) {
731 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
732 			n1 = TAILQ_FIRST(&devsoftc.devq);
733 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
734 			free(n1->dei_data, M_BUS);
735 			free(n1, M_BUS);
736 		}
737 	}
738 	mtx_unlock(&devsoftc.mtx);
739 	return (0);
740 }
741 
742 /* End of /dev/devctl code */
743 
744 TAILQ_HEAD(,device)	bus_data_devices;
745 static int bus_data_generation = 1;
746 
747 kobj_method_t null_methods[] = {
748 	{ 0, 0 }
749 };
750 
751 DEFINE_CLASS(null, null_methods, 0);
752 
753 /*
754  * Devclass implementation
755  */
756 
757 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
758 
759 
760 /**
761  * @internal
762  * @brief Find or create a device class
763  *
764  * If a device class with the name @p classname exists, return it,
765  * otherwise if @p create is non-zero create and return a new device
766  * class.
767  *
768  * If @p parentname is non-NULL, the parent of the devclass is set to
769  * the devclass of that name.
770  *
771  * @param classname	the devclass name to find or create
772  * @param parentname	the parent devclass name or @c NULL
773  * @param create	non-zero to create a devclass
774  */
775 static devclass_t
776 devclass_find_internal(const char *classname, const char *parentname,
777 		       int create)
778 {
779 	devclass_t dc;
780 
781 	PDEBUG(("looking for %s", classname));
782 	if (!classname)
783 		return (NULL);
784 
785 	TAILQ_FOREACH(dc, &devclasses, link) {
786 		if (!strcmp(dc->name, classname))
787 			break;
788 	}
789 
790 	if (create && !dc) {
791 		PDEBUG(("creating %s", classname));
792 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
793 		    M_BUS, M_NOWAIT|M_ZERO);
794 		if (!dc)
795 			return (NULL);
796 		dc->parent = NULL;
797 		dc->name = (char*) (dc + 1);
798 		strcpy(dc->name, classname);
799 		TAILQ_INIT(&dc->drivers);
800 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
801 
802 		bus_data_generation_update();
803 	}
804 
805 	/*
806 	 * If a parent class is specified, then set that as our parent so
807 	 * that this devclass will support drivers for the parent class as
808 	 * well.  If the parent class has the same name don't do this though
809 	 * as it creates a cycle that can trigger an infinite loop in
810 	 * device_probe_child() if a device exists for which there is no
811 	 * suitable driver.
812 	 */
813 	if (parentname && dc && !dc->parent &&
814 	    strcmp(classname, parentname) != 0) {
815 		dc->parent = devclass_find_internal(parentname, NULL, FALSE);
816 	}
817 
818 	return (dc);
819 }
820 
821 /**
822  * @brief Create a device class
823  *
824  * If a device class with the name @p classname exists, return it,
825  * otherwise create and return a new device class.
826  *
827  * @param classname	the devclass name to find or create
828  */
829 devclass_t
830 devclass_create(const char *classname)
831 {
832 	return (devclass_find_internal(classname, NULL, TRUE));
833 }
834 
835 /**
836  * @brief Find a device class
837  *
838  * If a device class with the name @p classname exists, return it,
839  * otherwise return @c NULL.
840  *
841  * @param classname	the devclass name to find
842  */
843 devclass_t
844 devclass_find(const char *classname)
845 {
846 	return (devclass_find_internal(classname, NULL, FALSE));
847 }
848 
849 /**
850  * @brief Add a device driver to a device class
851  *
852  * Add a device driver to a devclass. This is normally called
853  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
854  * all devices in the devclass will be called to allow them to attempt
855  * to re-probe any unmatched children.
856  *
857  * @param dc		the devclass to edit
858  * @param driver	the driver to register
859  */
860 int
861 devclass_add_driver(devclass_t dc, driver_t *driver)
862 {
863 	driverlink_t dl;
864 	int i;
865 
866 	PDEBUG(("%s", DRIVERNAME(driver)));
867 
868 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
869 	if (!dl)
870 		return (ENOMEM);
871 
872 	/*
873 	 * Compile the driver's methods. Also increase the reference count
874 	 * so that the class doesn't get freed when the last instance
875 	 * goes. This means we can safely use static methods and avoids a
876 	 * double-free in devclass_delete_driver.
877 	 */
878 	kobj_class_compile((kobj_class_t) driver);
879 
880 	/*
881 	 * Make sure the devclass which the driver is implementing exists.
882 	 */
883 	devclass_find_internal(driver->name, NULL, TRUE);
884 
885 	dl->driver = driver;
886 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
887 	driver->refs++;		/* XXX: kobj_mtx */
888 
889 	/*
890 	 * Call BUS_DRIVER_ADDED for any existing busses in this class.
891 	 */
892 	for (i = 0; i < dc->maxunit; i++)
893 		if (dc->devices[i])
894 			BUS_DRIVER_ADDED(dc->devices[i], driver);
895 
896 	bus_data_generation_update();
897 	return (0);
898 }
899 
900 /**
901  * @brief Delete a device driver from a device class
902  *
903  * Delete a device driver from a devclass. This is normally called
904  * automatically by DRIVER_MODULE().
905  *
906  * If the driver is currently attached to any devices,
907  * devclass_delete_driver() will first attempt to detach from each
908  * device. If one of the detach calls fails, the driver will not be
909  * deleted.
910  *
911  * @param dc		the devclass to edit
912  * @param driver	the driver to unregister
913  */
914 int
915 devclass_delete_driver(devclass_t busclass, driver_t *driver)
916 {
917 	devclass_t dc = devclass_find(driver->name);
918 	driverlink_t dl;
919 	device_t dev;
920 	int i;
921 	int error;
922 
923 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
924 
925 	if (!dc)
926 		return (0);
927 
928 	/*
929 	 * Find the link structure in the bus' list of drivers.
930 	 */
931 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
932 		if (dl->driver == driver)
933 			break;
934 	}
935 
936 	if (!dl) {
937 		PDEBUG(("%s not found in %s list", driver->name,
938 		    busclass->name));
939 		return (ENOENT);
940 	}
941 
942 	/*
943 	 * Disassociate from any devices.  We iterate through all the
944 	 * devices in the devclass of the driver and detach any which are
945 	 * using the driver and which have a parent in the devclass which
946 	 * we are deleting from.
947 	 *
948 	 * Note that since a driver can be in multiple devclasses, we
949 	 * should not detach devices which are not children of devices in
950 	 * the affected devclass.
951 	 */
952 	for (i = 0; i < dc->maxunit; i++) {
953 		if (dc->devices[i]) {
954 			dev = dc->devices[i];
955 			if (dev->driver == driver && dev->parent &&
956 			    dev->parent->devclass == busclass) {
957 				if ((error = device_detach(dev)) != 0)
958 					return (error);
959 				device_set_driver(dev, NULL);
960 			}
961 		}
962 	}
963 
964 	TAILQ_REMOVE(&busclass->drivers, dl, link);
965 	free(dl, M_BUS);
966 
967 	/* XXX: kobj_mtx */
968 	driver->refs--;
969 	if (driver->refs == 0)
970 		kobj_class_free((kobj_class_t) driver);
971 
972 	bus_data_generation_update();
973 	return (0);
974 }
975 
976 /**
977  * @brief Quiesces a set of device drivers from a device class
978  *
979  * Quiesce a device driver from a devclass. This is normally called
980  * automatically by DRIVER_MODULE().
981  *
982  * If the driver is currently attached to any devices,
983  * devclass_quiesece_driver() will first attempt to quiesce each
984  * device.
985  *
986  * @param dc		the devclass to edit
987  * @param driver	the driver to unregister
988  */
989 int
990 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
991 {
992 	devclass_t dc = devclass_find(driver->name);
993 	driverlink_t dl;
994 	device_t dev;
995 	int i;
996 	int error;
997 
998 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
999 
1000 	if (!dc)
1001 		return (0);
1002 
1003 	/*
1004 	 * Find the link structure in the bus' list of drivers.
1005 	 */
1006 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1007 		if (dl->driver == driver)
1008 			break;
1009 	}
1010 
1011 	if (!dl) {
1012 		PDEBUG(("%s not found in %s list", driver->name,
1013 		    busclass->name));
1014 		return (ENOENT);
1015 	}
1016 
1017 	/*
1018 	 * Quiesce all devices.  We iterate through all the devices in
1019 	 * the devclass of the driver and quiesce any which are using
1020 	 * the driver and which have a parent in the devclass which we
1021 	 * are quiescing.
1022 	 *
1023 	 * Note that since a driver can be in multiple devclasses, we
1024 	 * should not quiesce devices which are not children of
1025 	 * devices in the affected devclass.
1026 	 */
1027 	for (i = 0; i < dc->maxunit; i++) {
1028 		if (dc->devices[i]) {
1029 			dev = dc->devices[i];
1030 			if (dev->driver == driver && dev->parent &&
1031 			    dev->parent->devclass == busclass) {
1032 				if ((error = device_quiesce(dev)) != 0)
1033 					return (error);
1034 			}
1035 		}
1036 	}
1037 
1038 	return (0);
1039 }
1040 
1041 /**
1042  * @internal
1043  */
1044 static driverlink_t
1045 devclass_find_driver_internal(devclass_t dc, const char *classname)
1046 {
1047 	driverlink_t dl;
1048 
1049 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1050 
1051 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1052 		if (!strcmp(dl->driver->name, classname))
1053 			return (dl);
1054 	}
1055 
1056 	PDEBUG(("not found"));
1057 	return (NULL);
1058 }
1059 
1060 /**
1061  * @brief Search a devclass for a driver
1062  *
1063  * This function searches the devclass's list of drivers and returns
1064  * the first driver whose name is @p classname or @c NULL if there is
1065  * no driver of that name.
1066  *
1067  * @param dc		the devclass to search
1068  * @param classname	the driver name to search for
1069  */
1070 kobj_class_t
1071 devclass_find_driver(devclass_t dc, const char *classname)
1072 {
1073 	driverlink_t dl;
1074 
1075 	dl = devclass_find_driver_internal(dc, classname);
1076 	if (dl)
1077 		return (dl->driver);
1078 	return (NULL);
1079 }
1080 
1081 /**
1082  * @brief Return the name of the devclass
1083  */
1084 const char *
1085 devclass_get_name(devclass_t dc)
1086 {
1087 	return (dc->name);
1088 }
1089 
1090 /**
1091  * @brief Find a device given a unit number
1092  *
1093  * @param dc		the devclass to search
1094  * @param unit		the unit number to search for
1095  *
1096  * @returns		the device with the given unit number or @c
1097  *			NULL if there is no such device
1098  */
1099 device_t
1100 devclass_get_device(devclass_t dc, int unit)
1101 {
1102 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1103 		return (NULL);
1104 	return (dc->devices[unit]);
1105 }
1106 
1107 /**
1108  * @brief Find the softc field of a device given a unit number
1109  *
1110  * @param dc		the devclass to search
1111  * @param unit		the unit number to search for
1112  *
1113  * @returns		the softc field of the device with the given
1114  *			unit number or @c NULL if there is no such
1115  *			device
1116  */
1117 void *
1118 devclass_get_softc(devclass_t dc, int unit)
1119 {
1120 	device_t dev;
1121 
1122 	dev = devclass_get_device(dc, unit);
1123 	if (!dev)
1124 		return (NULL);
1125 
1126 	return (device_get_softc(dev));
1127 }
1128 
1129 /**
1130  * @brief Get a list of devices in the devclass
1131  *
1132  * An array containing a list of all the devices in the given devclass
1133  * is allocated and returned in @p *devlistp. The number of devices
1134  * in the array is returned in @p *devcountp. The caller should free
1135  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1136  *
1137  * @param dc		the devclass to examine
1138  * @param devlistp	points at location for array pointer return
1139  *			value
1140  * @param devcountp	points at location for array size return value
1141  *
1142  * @retval 0		success
1143  * @retval ENOMEM	the array allocation failed
1144  */
1145 int
1146 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1147 {
1148 	int count, i;
1149 	device_t *list;
1150 
1151 	count = devclass_get_count(dc);
1152 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1153 	if (!list)
1154 		return (ENOMEM);
1155 
1156 	count = 0;
1157 	for (i = 0; i < dc->maxunit; i++) {
1158 		if (dc->devices[i]) {
1159 			list[count] = dc->devices[i];
1160 			count++;
1161 		}
1162 	}
1163 
1164 	*devlistp = list;
1165 	*devcountp = count;
1166 
1167 	return (0);
1168 }
1169 
1170 /**
1171  * @brief Get a list of drivers in the devclass
1172  *
1173  * An array containing a list of pointers to all the drivers in the
1174  * given devclass is allocated and returned in @p *listp.  The number
1175  * of drivers in the array is returned in @p *countp. The caller should
1176  * free the array using @c free(p, M_TEMP).
1177  *
1178  * @param dc		the devclass to examine
1179  * @param listp		gives location for array pointer return value
1180  * @param countp	gives location for number of array elements
1181  *			return value
1182  *
1183  * @retval 0		success
1184  * @retval ENOMEM	the array allocation failed
1185  */
1186 int
1187 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1188 {
1189 	driverlink_t dl;
1190 	driver_t **list;
1191 	int count;
1192 
1193 	count = 0;
1194 	TAILQ_FOREACH(dl, &dc->drivers, link)
1195 		count++;
1196 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1197 	if (list == NULL)
1198 		return (ENOMEM);
1199 
1200 	count = 0;
1201 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1202 		list[count] = dl->driver;
1203 		count++;
1204 	}
1205 	*listp = list;
1206 	*countp = count;
1207 
1208 	return (0);
1209 }
1210 
1211 /**
1212  * @brief Get the number of devices in a devclass
1213  *
1214  * @param dc		the devclass to examine
1215  */
1216 int
1217 devclass_get_count(devclass_t dc)
1218 {
1219 	int count, i;
1220 
1221 	count = 0;
1222 	for (i = 0; i < dc->maxunit; i++)
1223 		if (dc->devices[i])
1224 			count++;
1225 	return (count);
1226 }
1227 
1228 /**
1229  * @brief Get the maximum unit number used in a devclass
1230  *
1231  * Note that this is one greater than the highest currently-allocated
1232  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1233  * that not even the devclass has been allocated yet.
1234  *
1235  * @param dc		the devclass to examine
1236  */
1237 int
1238 devclass_get_maxunit(devclass_t dc)
1239 {
1240 	if (dc == NULL)
1241 		return (-1);
1242 	return (dc->maxunit);
1243 }
1244 
1245 /**
1246  * @brief Find a free unit number in a devclass
1247  *
1248  * This function searches for the first unused unit number greater
1249  * that or equal to @p unit.
1250  *
1251  * @param dc		the devclass to examine
1252  * @param unit		the first unit number to check
1253  */
1254 int
1255 devclass_find_free_unit(devclass_t dc, int unit)
1256 {
1257 	if (dc == NULL)
1258 		return (unit);
1259 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1260 		unit++;
1261 	return (unit);
1262 }
1263 
1264 /**
1265  * @brief Set the parent of a devclass
1266  *
1267  * The parent class is normally initialised automatically by
1268  * DRIVER_MODULE().
1269  *
1270  * @param dc		the devclass to edit
1271  * @param pdc		the new parent devclass
1272  */
1273 void
1274 devclass_set_parent(devclass_t dc, devclass_t pdc)
1275 {
1276 	dc->parent = pdc;
1277 }
1278 
1279 /**
1280  * @brief Get the parent of a devclass
1281  *
1282  * @param dc		the devclass to examine
1283  */
1284 devclass_t
1285 devclass_get_parent(devclass_t dc)
1286 {
1287 	return (dc->parent);
1288 }
1289 
1290 struct sysctl_ctx_list *
1291 devclass_get_sysctl_ctx(devclass_t dc)
1292 {
1293 	return (&dc->sysctl_ctx);
1294 }
1295 
1296 struct sysctl_oid *
1297 devclass_get_sysctl_tree(devclass_t dc)
1298 {
1299 	return (dc->sysctl_tree);
1300 }
1301 
1302 /**
1303  * @internal
1304  * @brief Allocate a unit number
1305  *
1306  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1307  * will do). The allocated unit number is returned in @p *unitp.
1308 
1309  * @param dc		the devclass to allocate from
1310  * @param unitp		points at the location for the allocated unit
1311  *			number
1312  *
1313  * @retval 0		success
1314  * @retval EEXIST	the requested unit number is already allocated
1315  * @retval ENOMEM	memory allocation failure
1316  */
1317 static int
1318 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1319 {
1320 	const char *s;
1321 	int unit = *unitp;
1322 
1323 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1324 
1325 	/* Ask the parent bus if it wants to wire this device. */
1326 	if (unit == -1)
1327 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1328 		    &unit);
1329 
1330 	/* If we were given a wired unit number, check for existing device */
1331 	/* XXX imp XXX */
1332 	if (unit != -1) {
1333 		if (unit >= 0 && unit < dc->maxunit &&
1334 		    dc->devices[unit] != NULL) {
1335 			if (bootverbose)
1336 				printf("%s: %s%d already exists; skipping it\n",
1337 				    dc->name, dc->name, *unitp);
1338 			return (EEXIST);
1339 		}
1340 	} else {
1341 		/* Unwired device, find the next available slot for it */
1342 		unit = 0;
1343 		for (unit = 0;; unit++) {
1344 			/* If there is an "at" hint for a unit then skip it. */
1345 			if (resource_string_value(dc->name, unit, "at", &s) ==
1346 			    0)
1347 				continue;
1348 
1349 			/* If this device slot is already in use, skip it. */
1350 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1351 				continue;
1352 
1353 			break;
1354 		}
1355 	}
1356 
1357 	/*
1358 	 * We've selected a unit beyond the length of the table, so let's
1359 	 * extend the table to make room for all units up to and including
1360 	 * this one.
1361 	 */
1362 	if (unit >= dc->maxunit) {
1363 		device_t *newlist, *oldlist;
1364 		int newsize;
1365 
1366 		oldlist = dc->devices;
1367 		newsize = roundup((unit + 1), MINALLOCSIZE / sizeof(device_t));
1368 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1369 		if (!newlist)
1370 			return (ENOMEM);
1371 		if (oldlist != NULL)
1372 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1373 		bzero(newlist + dc->maxunit,
1374 		    sizeof(device_t) * (newsize - dc->maxunit));
1375 		dc->devices = newlist;
1376 		dc->maxunit = newsize;
1377 		if (oldlist != NULL)
1378 			free(oldlist, M_BUS);
1379 	}
1380 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1381 
1382 	*unitp = unit;
1383 	return (0);
1384 }
1385 
1386 /**
1387  * @internal
1388  * @brief Add a device to a devclass
1389  *
1390  * A unit number is allocated for the device (using the device's
1391  * preferred unit number if any) and the device is registered in the
1392  * devclass. This allows the device to be looked up by its unit
1393  * number, e.g. by decoding a dev_t minor number.
1394  *
1395  * @param dc		the devclass to add to
1396  * @param dev		the device to add
1397  *
1398  * @retval 0		success
1399  * @retval EEXIST	the requested unit number is already allocated
1400  * @retval ENOMEM	memory allocation failure
1401  */
1402 static int
1403 devclass_add_device(devclass_t dc, device_t dev)
1404 {
1405 	int buflen, error;
1406 
1407 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1408 
1409 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, dev->unit);
1410 	if (buflen < 0)
1411 		return (ENOMEM);
1412 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1413 	if (!dev->nameunit)
1414 		return (ENOMEM);
1415 
1416 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1417 		free(dev->nameunit, M_BUS);
1418 		dev->nameunit = NULL;
1419 		return (error);
1420 	}
1421 	dc->devices[dev->unit] = dev;
1422 	dev->devclass = dc;
1423 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1424 
1425 	return (0);
1426 }
1427 
1428 /**
1429  * @internal
1430  * @brief Delete a device from a devclass
1431  *
1432  * The device is removed from the devclass's device list and its unit
1433  * number is freed.
1434 
1435  * @param dc		the devclass to delete from
1436  * @param dev		the device to delete
1437  *
1438  * @retval 0		success
1439  */
1440 static int
1441 devclass_delete_device(devclass_t dc, device_t dev)
1442 {
1443 	if (!dc || !dev)
1444 		return (0);
1445 
1446 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1447 
1448 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1449 		panic("devclass_delete_device: inconsistent device class");
1450 	dc->devices[dev->unit] = NULL;
1451 	if (dev->flags & DF_WILDCARD)
1452 		dev->unit = -1;
1453 	dev->devclass = NULL;
1454 	free(dev->nameunit, M_BUS);
1455 	dev->nameunit = NULL;
1456 
1457 	return (0);
1458 }
1459 
1460 /**
1461  * @internal
1462  * @brief Make a new device and add it as a child of @p parent
1463  *
1464  * @param parent	the parent of the new device
1465  * @param name		the devclass name of the new device or @c NULL
1466  *			to leave the devclass unspecified
1467  * @parem unit		the unit number of the new device of @c -1 to
1468  *			leave the unit number unspecified
1469  *
1470  * @returns the new device
1471  */
1472 static device_t
1473 make_device(device_t parent, const char *name, int unit)
1474 {
1475 	device_t dev;
1476 	devclass_t dc;
1477 
1478 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1479 
1480 	if (name) {
1481 		dc = devclass_find_internal(name, NULL, TRUE);
1482 		if (!dc) {
1483 			printf("make_device: can't find device class %s\n",
1484 			    name);
1485 			return (NULL);
1486 		}
1487 	} else {
1488 		dc = NULL;
1489 	}
1490 
1491 	dev = malloc(sizeof(struct device), M_BUS, M_NOWAIT|M_ZERO);
1492 	if (!dev)
1493 		return (NULL);
1494 
1495 	dev->parent = parent;
1496 	TAILQ_INIT(&dev->children);
1497 	kobj_init((kobj_t) dev, &null_class);
1498 	dev->driver = NULL;
1499 	dev->devclass = NULL;
1500 	dev->unit = unit;
1501 	dev->nameunit = NULL;
1502 	dev->desc = NULL;
1503 	dev->busy = 0;
1504 	dev->devflags = 0;
1505 	dev->flags = DF_ENABLED;
1506 	dev->order = 0;
1507 	if (unit == -1)
1508 		dev->flags |= DF_WILDCARD;
1509 	if (name) {
1510 		dev->flags |= DF_FIXEDCLASS;
1511 		if (devclass_add_device(dc, dev)) {
1512 			kobj_delete((kobj_t) dev, M_BUS);
1513 			return (NULL);
1514 		}
1515 	}
1516 	dev->ivars = NULL;
1517 	dev->softc = NULL;
1518 
1519 	dev->state = DS_NOTPRESENT;
1520 
1521 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1522 	bus_data_generation_update();
1523 
1524 	return (dev);
1525 }
1526 
1527 /**
1528  * @internal
1529  * @brief Print a description of a device.
1530  */
1531 static int
1532 device_print_child(device_t dev, device_t child)
1533 {
1534 	int retval = 0;
1535 
1536 	if (device_is_alive(child))
1537 		retval += BUS_PRINT_CHILD(dev, child);
1538 	else
1539 		retval += device_printf(child, " not found\n");
1540 
1541 	return (retval);
1542 }
1543 
1544 /**
1545  * @brief Create a new device
1546  *
1547  * This creates a new device and adds it as a child of an existing
1548  * parent device. The new device will be added after the last existing
1549  * child with order zero.
1550  *
1551  * @param dev		the device which will be the parent of the
1552  *			new child device
1553  * @param name		devclass name for new device or @c NULL if not
1554  *			specified
1555  * @param unit		unit number for new device or @c -1 if not
1556  *			specified
1557  *
1558  * @returns		the new device
1559  */
1560 device_t
1561 device_add_child(device_t dev, const char *name, int unit)
1562 {
1563 	return (device_add_child_ordered(dev, 0, name, unit));
1564 }
1565 
1566 /**
1567  * @brief Create a new device
1568  *
1569  * This creates a new device and adds it as a child of an existing
1570  * parent device. The new device will be added after the last existing
1571  * child with the same order.
1572  *
1573  * @param dev		the device which will be the parent of the
1574  *			new child device
1575  * @param order		a value which is used to partially sort the
1576  *			children of @p dev - devices created using
1577  *			lower values of @p order appear first in @p
1578  *			dev's list of children
1579  * @param name		devclass name for new device or @c NULL if not
1580  *			specified
1581  * @param unit		unit number for new device or @c -1 if not
1582  *			specified
1583  *
1584  * @returns		the new device
1585  */
1586 device_t
1587 device_add_child_ordered(device_t dev, int order, const char *name, int unit)
1588 {
1589 	device_t child;
1590 	device_t place;
1591 
1592 	PDEBUG(("%s at %s with order %d as unit %d",
1593 	    name, DEVICENAME(dev), order, unit));
1594 
1595 	child = make_device(dev, name, unit);
1596 	if (child == NULL)
1597 		return (child);
1598 	child->order = order;
1599 
1600 	TAILQ_FOREACH(place, &dev->children, link) {
1601 		if (place->order > order)
1602 			break;
1603 	}
1604 
1605 	if (place) {
1606 		/*
1607 		 * The device 'place' is the first device whose order is
1608 		 * greater than the new child.
1609 		 */
1610 		TAILQ_INSERT_BEFORE(place, child, link);
1611 	} else {
1612 		/*
1613 		 * The new child's order is greater or equal to the order of
1614 		 * any existing device. Add the child to the tail of the list.
1615 		 */
1616 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1617 	}
1618 
1619 	bus_data_generation_update();
1620 	return (child);
1621 }
1622 
1623 /**
1624  * @brief Delete a device
1625  *
1626  * This function deletes a device along with all of its children. If
1627  * the device currently has a driver attached to it, the device is
1628  * detached first using device_detach().
1629  *
1630  * @param dev		the parent device
1631  * @param child		the device to delete
1632  *
1633  * @retval 0		success
1634  * @retval non-zero	a unit error code describing the error
1635  */
1636 int
1637 device_delete_child(device_t dev, device_t child)
1638 {
1639 	int error;
1640 	device_t grandchild;
1641 
1642 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1643 
1644 	/* remove children first */
1645 	while ( (grandchild = TAILQ_FIRST(&child->children)) ) {
1646 		error = device_delete_child(child, grandchild);
1647 		if (error)
1648 			return (error);
1649 	}
1650 
1651 	if ((error = device_detach(child)) != 0)
1652 		return (error);
1653 	if (child->devclass)
1654 		devclass_delete_device(child->devclass, child);
1655 	TAILQ_REMOVE(&dev->children, child, link);
1656 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1657 	kobj_delete((kobj_t) child, M_BUS);
1658 
1659 	bus_data_generation_update();
1660 	return (0);
1661 }
1662 
1663 /**
1664  * @brief Find a device given a unit number
1665  *
1666  * This is similar to devclass_get_devices() but only searches for
1667  * devices which have @p dev as a parent.
1668  *
1669  * @param dev		the parent device to search
1670  * @param unit		the unit number to search for.  If the unit is -1,
1671  *			return the first child of @p dev which has name
1672  *			@p classname (that is, the one with the lowest unit.)
1673  *
1674  * @returns		the device with the given unit number or @c
1675  *			NULL if there is no such device
1676  */
1677 device_t
1678 device_find_child(device_t dev, const char *classname, int unit)
1679 {
1680 	devclass_t dc;
1681 	device_t child;
1682 
1683 	dc = devclass_find(classname);
1684 	if (!dc)
1685 		return (NULL);
1686 
1687 	if (unit != -1) {
1688 		child = devclass_get_device(dc, unit);
1689 		if (child && child->parent == dev)
1690 			return (child);
1691 	} else {
1692 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
1693 			child = devclass_get_device(dc, unit);
1694 			if (child && child->parent == dev)
1695 				return (child);
1696 		}
1697 	}
1698 	return (NULL);
1699 }
1700 
1701 /**
1702  * @internal
1703  */
1704 static driverlink_t
1705 first_matching_driver(devclass_t dc, device_t dev)
1706 {
1707 	if (dev->devclass)
1708 		return (devclass_find_driver_internal(dc, dev->devclass->name));
1709 	return (TAILQ_FIRST(&dc->drivers));
1710 }
1711 
1712 /**
1713  * @internal
1714  */
1715 static driverlink_t
1716 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
1717 {
1718 	if (dev->devclass) {
1719 		driverlink_t dl;
1720 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
1721 			if (!strcmp(dev->devclass->name, dl->driver->name))
1722 				return (dl);
1723 		return (NULL);
1724 	}
1725 	return (TAILQ_NEXT(last, link));
1726 }
1727 
1728 /**
1729  * @internal
1730  */
1731 int
1732 device_probe_child(device_t dev, device_t child)
1733 {
1734 	devclass_t dc;
1735 	driverlink_t best = NULL;
1736 	driverlink_t dl;
1737 	int result, pri = 0;
1738 	int hasclass = (child->devclass != 0);
1739 
1740 	GIANT_REQUIRED;
1741 
1742 	dc = dev->devclass;
1743 	if (!dc)
1744 		panic("device_probe_child: parent device has no devclass");
1745 
1746 	/*
1747 	 * If the state is already probed, then return.  However, don't
1748 	 * return if we can rebid this object.
1749 	 */
1750 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
1751 		return (0);
1752 
1753 	for (; dc; dc = dc->parent) {
1754 		for (dl = first_matching_driver(dc, child);
1755 		     dl;
1756 		     dl = next_matching_driver(dc, child, dl)) {
1757 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
1758 			device_set_driver(child, dl->driver);
1759 			if (!hasclass)
1760 				device_set_devclass(child, dl->driver->name);
1761 
1762 			/* Fetch any flags for the device before probing. */
1763 			resource_int_value(dl->driver->name, child->unit,
1764 			    "flags", &child->devflags);
1765 
1766 			result = DEVICE_PROBE(child);
1767 
1768 			/* Reset flags and devclass before the next probe. */
1769 			child->devflags = 0;
1770 			if (!hasclass)
1771 				device_set_devclass(child, NULL);
1772 
1773 			/*
1774 			 * If the driver returns SUCCESS, there can be
1775 			 * no higher match for this device.
1776 			 */
1777 			if (result == 0) {
1778 				best = dl;
1779 				pri = 0;
1780 				break;
1781 			}
1782 
1783 			/*
1784 			 * The driver returned an error so it
1785 			 * certainly doesn't match.
1786 			 */
1787 			if (result > 0) {
1788 				device_set_driver(child, NULL);
1789 				continue;
1790 			}
1791 
1792 			/*
1793 			 * A priority lower than SUCCESS, remember the
1794 			 * best matching driver. Initialise the value
1795 			 * of pri for the first match.
1796 			 */
1797 			if (best == NULL || result > pri) {
1798 				/*
1799 				 * Probes that return BUS_PROBE_NOWILDCARD
1800 				 * or lower only match when they are set
1801 				 * in stone by the parent bus.
1802 				 */
1803 				if (result <= BUS_PROBE_NOWILDCARD &&
1804 				    child->flags & DF_WILDCARD)
1805 					continue;
1806 				best = dl;
1807 				pri = result;
1808 				continue;
1809 			}
1810 		}
1811 		/*
1812 		 * If we have an unambiguous match in this devclass,
1813 		 * don't look in the parent.
1814 		 */
1815 		if (best && pri == 0)
1816 			break;
1817 	}
1818 
1819 	/*
1820 	 * If we found a driver, change state and initialise the devclass.
1821 	 */
1822 	/* XXX What happens if we rebid and got no best? */
1823 	if (best) {
1824 		/*
1825 		 * If this device was atached, and we were asked to
1826 		 * rescan, and it is a different driver, then we have
1827 		 * to detach the old driver and reattach this new one.
1828 		 * Note, we don't have to check for DF_REBID here
1829 		 * because if the state is > DS_ALIVE, we know it must
1830 		 * be.
1831 		 *
1832 		 * This assumes that all DF_REBID drivers can have
1833 		 * their probe routine called at any time and that
1834 		 * they are idempotent as well as completely benign in
1835 		 * normal operations.
1836 		 *
1837 		 * We also have to make sure that the detach
1838 		 * succeeded, otherwise we fail the operation (or
1839 		 * maybe it should just fail silently?  I'm torn).
1840 		 */
1841 		if (child->state > DS_ALIVE && best->driver != child->driver)
1842 			if ((result = device_detach(dev)) != 0)
1843 				return (result);
1844 
1845 		/* Set the winning driver, devclass, and flags. */
1846 		if (!child->devclass)
1847 			device_set_devclass(child, best->driver->name);
1848 		device_set_driver(child, best->driver);
1849 		resource_int_value(best->driver->name, child->unit,
1850 		    "flags", &child->devflags);
1851 
1852 		if (pri < 0) {
1853 			/*
1854 			 * A bit bogus. Call the probe method again to make
1855 			 * sure that we have the right description.
1856 			 */
1857 			DEVICE_PROBE(child);
1858 #if 0
1859 			child->flags |= DF_REBID;
1860 #endif
1861 		} else
1862 			child->flags &= ~DF_REBID;
1863 		child->state = DS_ALIVE;
1864 
1865 		bus_data_generation_update();
1866 		return (0);
1867 	}
1868 
1869 	return (ENXIO);
1870 }
1871 
1872 /**
1873  * @brief Return the parent of a device
1874  */
1875 device_t
1876 device_get_parent(device_t dev)
1877 {
1878 	return (dev->parent);
1879 }
1880 
1881 /**
1882  * @brief Get a list of children of a device
1883  *
1884  * An array containing a list of all the children of the given device
1885  * is allocated and returned in @p *devlistp. The number of devices
1886  * in the array is returned in @p *devcountp. The caller should free
1887  * the array using @c free(p, M_TEMP).
1888  *
1889  * @param dev		the device to examine
1890  * @param devlistp	points at location for array pointer return
1891  *			value
1892  * @param devcountp	points at location for array size return value
1893  *
1894  * @retval 0		success
1895  * @retval ENOMEM	the array allocation failed
1896  */
1897 int
1898 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
1899 {
1900 	int count;
1901 	device_t child;
1902 	device_t *list;
1903 
1904 	count = 0;
1905 	TAILQ_FOREACH(child, &dev->children, link) {
1906 		count++;
1907 	}
1908 
1909 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1910 	if (!list)
1911 		return (ENOMEM);
1912 
1913 	count = 0;
1914 	TAILQ_FOREACH(child, &dev->children, link) {
1915 		list[count] = child;
1916 		count++;
1917 	}
1918 
1919 	*devlistp = list;
1920 	*devcountp = count;
1921 
1922 	return (0);
1923 }
1924 
1925 /**
1926  * @brief Return the current driver for the device or @c NULL if there
1927  * is no driver currently attached
1928  */
1929 driver_t *
1930 device_get_driver(device_t dev)
1931 {
1932 	return (dev->driver);
1933 }
1934 
1935 /**
1936  * @brief Return the current devclass for the device or @c NULL if
1937  * there is none.
1938  */
1939 devclass_t
1940 device_get_devclass(device_t dev)
1941 {
1942 	return (dev->devclass);
1943 }
1944 
1945 /**
1946  * @brief Return the name of the device's devclass or @c NULL if there
1947  * is none.
1948  */
1949 const char *
1950 device_get_name(device_t dev)
1951 {
1952 	if (dev != NULL && dev->devclass)
1953 		return (devclass_get_name(dev->devclass));
1954 	return (NULL);
1955 }
1956 
1957 /**
1958  * @brief Return a string containing the device's devclass name
1959  * followed by an ascii representation of the device's unit number
1960  * (e.g. @c "foo2").
1961  */
1962 const char *
1963 device_get_nameunit(device_t dev)
1964 {
1965 	return (dev->nameunit);
1966 }
1967 
1968 /**
1969  * @brief Return the device's unit number.
1970  */
1971 int
1972 device_get_unit(device_t dev)
1973 {
1974 	return (dev->unit);
1975 }
1976 
1977 /**
1978  * @brief Return the device's description string
1979  */
1980 const char *
1981 device_get_desc(device_t dev)
1982 {
1983 	return (dev->desc);
1984 }
1985 
1986 /**
1987  * @brief Return the device's flags
1988  */
1989 u_int32_t
1990 device_get_flags(device_t dev)
1991 {
1992 	return (dev->devflags);
1993 }
1994 
1995 struct sysctl_ctx_list *
1996 device_get_sysctl_ctx(device_t dev)
1997 {
1998 	return (&dev->sysctl_ctx);
1999 }
2000 
2001 struct sysctl_oid *
2002 device_get_sysctl_tree(device_t dev)
2003 {
2004 	return (dev->sysctl_tree);
2005 }
2006 
2007 /**
2008  * @brief Print the name of the device followed by a colon and a space
2009  *
2010  * @returns the number of characters printed
2011  */
2012 int
2013 device_print_prettyname(device_t dev)
2014 {
2015 	const char *name = device_get_name(dev);
2016 
2017 	if (name == 0)
2018 		return (printf("unknown: "));
2019 	return (printf("%s%d: ", name, device_get_unit(dev)));
2020 }
2021 
2022 /**
2023  * @brief Print the name of the device followed by a colon, a space
2024  * and the result of calling vprintf() with the value of @p fmt and
2025  * the following arguments.
2026  *
2027  * @returns the number of characters printed
2028  */
2029 int
2030 device_printf(device_t dev, const char * fmt, ...)
2031 {
2032 	va_list ap;
2033 	int retval;
2034 
2035 	retval = device_print_prettyname(dev);
2036 	va_start(ap, fmt);
2037 	retval += vprintf(fmt, ap);
2038 	va_end(ap);
2039 	return (retval);
2040 }
2041 
2042 /**
2043  * @internal
2044  */
2045 static void
2046 device_set_desc_internal(device_t dev, const char* desc, int copy)
2047 {
2048 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2049 		free(dev->desc, M_BUS);
2050 		dev->flags &= ~DF_DESCMALLOCED;
2051 		dev->desc = NULL;
2052 	}
2053 
2054 	if (copy && desc) {
2055 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2056 		if (dev->desc) {
2057 			strcpy(dev->desc, desc);
2058 			dev->flags |= DF_DESCMALLOCED;
2059 		}
2060 	} else {
2061 		/* Avoid a -Wcast-qual warning */
2062 		dev->desc = (char *)(uintptr_t) desc;
2063 	}
2064 
2065 	bus_data_generation_update();
2066 }
2067 
2068 /**
2069  * @brief Set the device's description
2070  *
2071  * The value of @c desc should be a string constant that will not
2072  * change (at least until the description is changed in a subsequent
2073  * call to device_set_desc() or device_set_desc_copy()).
2074  */
2075 void
2076 device_set_desc(device_t dev, const char* desc)
2077 {
2078 	device_set_desc_internal(dev, desc, FALSE);
2079 }
2080 
2081 /**
2082  * @brief Set the device's description
2083  *
2084  * The string pointed to by @c desc is copied. Use this function if
2085  * the device description is generated, (e.g. with sprintf()).
2086  */
2087 void
2088 device_set_desc_copy(device_t dev, const char* desc)
2089 {
2090 	device_set_desc_internal(dev, desc, TRUE);
2091 }
2092 
2093 /**
2094  * @brief Set the device's flags
2095  */
2096 void
2097 device_set_flags(device_t dev, u_int32_t flags)
2098 {
2099 	dev->devflags = flags;
2100 }
2101 
2102 /**
2103  * @brief Return the device's softc field
2104  *
2105  * The softc is allocated and zeroed when a driver is attached, based
2106  * on the size field of the driver.
2107  */
2108 void *
2109 device_get_softc(device_t dev)
2110 {
2111 	return (dev->softc);
2112 }
2113 
2114 /**
2115  * @brief Set the device's softc field
2116  *
2117  * Most drivers do not need to use this since the softc is allocated
2118  * automatically when the driver is attached.
2119  */
2120 void
2121 device_set_softc(device_t dev, void *softc)
2122 {
2123 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2124 		free(dev->softc, M_BUS_SC);
2125 	dev->softc = softc;
2126 	if (dev->softc)
2127 		dev->flags |= DF_EXTERNALSOFTC;
2128 	else
2129 		dev->flags &= ~DF_EXTERNALSOFTC;
2130 }
2131 
2132 /**
2133  * @brief Get the device's ivars field
2134  *
2135  * The ivars field is used by the parent device to store per-device
2136  * state (e.g. the physical location of the device or a list of
2137  * resources).
2138  */
2139 void *
2140 device_get_ivars(device_t dev)
2141 {
2142 
2143 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2144 	return (dev->ivars);
2145 }
2146 
2147 /**
2148  * @brief Set the device's ivars field
2149  */
2150 void
2151 device_set_ivars(device_t dev, void * ivars)
2152 {
2153 
2154 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2155 	dev->ivars = ivars;
2156 }
2157 
2158 /**
2159  * @brief Return the device's state
2160  */
2161 device_state_t
2162 device_get_state(device_t dev)
2163 {
2164 	return (dev->state);
2165 }
2166 
2167 /**
2168  * @brief Set the DF_ENABLED flag for the device
2169  */
2170 void
2171 device_enable(device_t dev)
2172 {
2173 	dev->flags |= DF_ENABLED;
2174 }
2175 
2176 /**
2177  * @brief Clear the DF_ENABLED flag for the device
2178  */
2179 void
2180 device_disable(device_t dev)
2181 {
2182 	dev->flags &= ~DF_ENABLED;
2183 }
2184 
2185 /**
2186  * @brief Increment the busy counter for the device
2187  */
2188 void
2189 device_busy(device_t dev)
2190 {
2191 	if (dev->state < DS_ATTACHED)
2192 		panic("device_busy: called for unattached device");
2193 	if (dev->busy == 0 && dev->parent)
2194 		device_busy(dev->parent);
2195 	dev->busy++;
2196 	dev->state = DS_BUSY;
2197 }
2198 
2199 /**
2200  * @brief Decrement the busy counter for the device
2201  */
2202 void
2203 device_unbusy(device_t dev)
2204 {
2205 	if (dev->state != DS_BUSY)
2206 		panic("device_unbusy: called for non-busy device %s",
2207 		    device_get_nameunit(dev));
2208 	dev->busy--;
2209 	if (dev->busy == 0) {
2210 		if (dev->parent)
2211 			device_unbusy(dev->parent);
2212 		dev->state = DS_ATTACHED;
2213 	}
2214 }
2215 
2216 /**
2217  * @brief Set the DF_QUIET flag for the device
2218  */
2219 void
2220 device_quiet(device_t dev)
2221 {
2222 	dev->flags |= DF_QUIET;
2223 }
2224 
2225 /**
2226  * @brief Clear the DF_QUIET flag for the device
2227  */
2228 void
2229 device_verbose(device_t dev)
2230 {
2231 	dev->flags &= ~DF_QUIET;
2232 }
2233 
2234 /**
2235  * @brief Return non-zero if the DF_QUIET flag is set on the device
2236  */
2237 int
2238 device_is_quiet(device_t dev)
2239 {
2240 	return ((dev->flags & DF_QUIET) != 0);
2241 }
2242 
2243 /**
2244  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2245  */
2246 int
2247 device_is_enabled(device_t dev)
2248 {
2249 	return ((dev->flags & DF_ENABLED) != 0);
2250 }
2251 
2252 /**
2253  * @brief Return non-zero if the device was successfully probed
2254  */
2255 int
2256 device_is_alive(device_t dev)
2257 {
2258 	return (dev->state >= DS_ALIVE);
2259 }
2260 
2261 /**
2262  * @brief Return non-zero if the device currently has a driver
2263  * attached to it
2264  */
2265 int
2266 device_is_attached(device_t dev)
2267 {
2268 	return (dev->state >= DS_ATTACHED);
2269 }
2270 
2271 /**
2272  * @brief Set the devclass of a device
2273  * @see devclass_add_device().
2274  */
2275 int
2276 device_set_devclass(device_t dev, const char *classname)
2277 {
2278 	devclass_t dc;
2279 	int error;
2280 
2281 	if (!classname) {
2282 		if (dev->devclass)
2283 			devclass_delete_device(dev->devclass, dev);
2284 		return (0);
2285 	}
2286 
2287 	if (dev->devclass) {
2288 		printf("device_set_devclass: device class already set\n");
2289 		return (EINVAL);
2290 	}
2291 
2292 	dc = devclass_find_internal(classname, NULL, TRUE);
2293 	if (!dc)
2294 		return (ENOMEM);
2295 
2296 	error = devclass_add_device(dc, dev);
2297 
2298 	bus_data_generation_update();
2299 	return (error);
2300 }
2301 
2302 /**
2303  * @brief Set the driver of a device
2304  *
2305  * @retval 0		success
2306  * @retval EBUSY	the device already has a driver attached
2307  * @retval ENOMEM	a memory allocation failure occurred
2308  */
2309 int
2310 device_set_driver(device_t dev, driver_t *driver)
2311 {
2312 	if (dev->state >= DS_ATTACHED)
2313 		return (EBUSY);
2314 
2315 	if (dev->driver == driver)
2316 		return (0);
2317 
2318 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2319 		free(dev->softc, M_BUS_SC);
2320 		dev->softc = NULL;
2321 	}
2322 	kobj_delete((kobj_t) dev, NULL);
2323 	dev->driver = driver;
2324 	if (driver) {
2325 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2326 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2327 			dev->softc = malloc(driver->size, M_BUS_SC,
2328 			    M_NOWAIT | M_ZERO);
2329 			if (!dev->softc) {
2330 				kobj_delete((kobj_t) dev, NULL);
2331 				kobj_init((kobj_t) dev, &null_class);
2332 				dev->driver = NULL;
2333 				return (ENOMEM);
2334 			}
2335 		}
2336 	} else {
2337 		kobj_init((kobj_t) dev, &null_class);
2338 	}
2339 
2340 	bus_data_generation_update();
2341 	return (0);
2342 }
2343 
2344 /**
2345  * @brief Probe a device, and return this status.
2346  *
2347  * This function is the core of the device autoconfiguration
2348  * system. Its purpose is to select a suitable driver for a device and
2349  * then call that driver to initialise the hardware appropriately. The
2350  * driver is selected by calling the DEVICE_PROBE() method of a set of
2351  * candidate drivers and then choosing the driver which returned the
2352  * best value. This driver is then attached to the device using
2353  * device_attach().
2354  *
2355  * The set of suitable drivers is taken from the list of drivers in
2356  * the parent device's devclass. If the device was originally created
2357  * with a specific class name (see device_add_child()), only drivers
2358  * with that name are probed, otherwise all drivers in the devclass
2359  * are probed. If no drivers return successful probe values in the
2360  * parent devclass, the search continues in the parent of that
2361  * devclass (see devclass_get_parent()) if any.
2362  *
2363  * @param dev		the device to initialise
2364  *
2365  * @retval 0		success
2366  * @retval ENXIO	no driver was found
2367  * @retval ENOMEM	memory allocation failure
2368  * @retval non-zero	some other unix error code
2369  * @retval -1		Device already attached
2370  */
2371 int
2372 device_probe(device_t dev)
2373 {
2374 	int error;
2375 
2376 	GIANT_REQUIRED;
2377 
2378 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2379 		return (-1);
2380 
2381 	if (!(dev->flags & DF_ENABLED)) {
2382 		if (bootverbose && device_get_name(dev) != NULL) {
2383 			device_print_prettyname(dev);
2384 			printf("not probed (disabled)\n");
2385 		}
2386 		return (-1);
2387 	}
2388 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2389 		if (!(dev->flags & DF_DONENOMATCH)) {
2390 			BUS_PROBE_NOMATCH(dev->parent, dev);
2391 			devnomatch(dev);
2392 			dev->flags |= DF_DONENOMATCH;
2393 		}
2394 		return (error);
2395 	}
2396 	return (0);
2397 }
2398 
2399 /**
2400  * @brief Probe a device and attach a driver if possible
2401  *
2402  * calls device_probe() and attaches if that was successful.
2403  */
2404 int
2405 device_probe_and_attach(device_t dev)
2406 {
2407 	int error;
2408 
2409 	GIANT_REQUIRED;
2410 
2411 	error = device_probe(dev);
2412 	if (error == -1)
2413 		return (0);
2414 	else if (error != 0)
2415 		return (error);
2416 	return (device_attach(dev));
2417 }
2418 
2419 /**
2420  * @brief Attach a device driver to a device
2421  *
2422  * This function is a wrapper around the DEVICE_ATTACH() driver
2423  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2424  * device's sysctl tree, optionally prints a description of the device
2425  * and queues a notification event for user-based device management
2426  * services.
2427  *
2428  * Normally this function is only called internally from
2429  * device_probe_and_attach().
2430  *
2431  * @param dev		the device to initialise
2432  *
2433  * @retval 0		success
2434  * @retval ENXIO	no driver was found
2435  * @retval ENOMEM	memory allocation failure
2436  * @retval non-zero	some other unix error code
2437  */
2438 int
2439 device_attach(device_t dev)
2440 {
2441 	int error;
2442 
2443 	device_sysctl_init(dev);
2444 	if (!device_is_quiet(dev))
2445 		device_print_child(dev->parent, dev);
2446 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2447 		printf("device_attach: %s%d attach returned %d\n",
2448 		    dev->driver->name, dev->unit, error);
2449 		/* Unset the class; set in device_probe_child */
2450 		if (dev->devclass == NULL)
2451 			device_set_devclass(dev, NULL);
2452 		device_set_driver(dev, NULL);
2453 		device_sysctl_fini(dev);
2454 		dev->state = DS_NOTPRESENT;
2455 		return (error);
2456 	}
2457 	device_sysctl_update(dev);
2458 	dev->state = DS_ATTACHED;
2459 	devadded(dev);
2460 	return (0);
2461 }
2462 
2463 /**
2464  * @brief Detach a driver from a device
2465  *
2466  * This function is a wrapper around the DEVICE_DETACH() driver
2467  * method. If the call to DEVICE_DETACH() succeeds, it calls
2468  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
2469  * notification event for user-based device management services and
2470  * cleans up the device's sysctl tree.
2471  *
2472  * @param dev		the device to un-initialise
2473  *
2474  * @retval 0		success
2475  * @retval ENXIO	no driver was found
2476  * @retval ENOMEM	memory allocation failure
2477  * @retval non-zero	some other unix error code
2478  */
2479 int
2480 device_detach(device_t dev)
2481 {
2482 	int error;
2483 
2484 	GIANT_REQUIRED;
2485 
2486 	PDEBUG(("%s", DEVICENAME(dev)));
2487 	if (dev->state == DS_BUSY)
2488 		return (EBUSY);
2489 	if (dev->state != DS_ATTACHED)
2490 		return (0);
2491 
2492 	if ((error = DEVICE_DETACH(dev)) != 0)
2493 		return (error);
2494 	devremoved(dev);
2495 	if (!device_is_quiet(dev))
2496 		device_printf(dev, "detached\n");
2497 	if (dev->parent)
2498 		BUS_CHILD_DETACHED(dev->parent, dev);
2499 
2500 	if (!(dev->flags & DF_FIXEDCLASS))
2501 		devclass_delete_device(dev->devclass, dev);
2502 
2503 	dev->state = DS_NOTPRESENT;
2504 	device_set_driver(dev, NULL);
2505 	device_set_desc(dev, NULL);
2506 	device_sysctl_fini(dev);
2507 
2508 	return (0);
2509 }
2510 
2511 /**
2512  * @brief Tells a driver to quiesce itself.
2513  *
2514  * This function is a wrapper around the DEVICE_QUIESCE() driver
2515  * method. If the call to DEVICE_QUIESCE() succeeds.
2516  *
2517  * @param dev		the device to quiesce
2518  *
2519  * @retval 0		success
2520  * @retval ENXIO	no driver was found
2521  * @retval ENOMEM	memory allocation failure
2522  * @retval non-zero	some other unix error code
2523  */
2524 int
2525 device_quiesce(device_t dev)
2526 {
2527 
2528 	PDEBUG(("%s", DEVICENAME(dev)));
2529 	if (dev->state == DS_BUSY)
2530 		return (EBUSY);
2531 	if (dev->state != DS_ATTACHED)
2532 		return (0);
2533 
2534 	return (DEVICE_QUIESCE(dev));
2535 }
2536 
2537 /**
2538  * @brief Notify a device of system shutdown
2539  *
2540  * This function calls the DEVICE_SHUTDOWN() driver method if the
2541  * device currently has an attached driver.
2542  *
2543  * @returns the value returned by DEVICE_SHUTDOWN()
2544  */
2545 int
2546 device_shutdown(device_t dev)
2547 {
2548 	if (dev->state < DS_ATTACHED)
2549 		return (0);
2550 	return (DEVICE_SHUTDOWN(dev));
2551 }
2552 
2553 /**
2554  * @brief Set the unit number of a device
2555  *
2556  * This function can be used to override the unit number used for a
2557  * device (e.g. to wire a device to a pre-configured unit number).
2558  */
2559 int
2560 device_set_unit(device_t dev, int unit)
2561 {
2562 	devclass_t dc;
2563 	int err;
2564 
2565 	dc = device_get_devclass(dev);
2566 	if (unit < dc->maxunit && dc->devices[unit])
2567 		return (EBUSY);
2568 	err = devclass_delete_device(dc, dev);
2569 	if (err)
2570 		return (err);
2571 	dev->unit = unit;
2572 	err = devclass_add_device(dc, dev);
2573 	if (err)
2574 		return (err);
2575 
2576 	bus_data_generation_update();
2577 	return (0);
2578 }
2579 
2580 /*======================================*/
2581 /*
2582  * Some useful method implementations to make life easier for bus drivers.
2583  */
2584 
2585 /**
2586  * @brief Initialise a resource list.
2587  *
2588  * @param rl		the resource list to initialise
2589  */
2590 void
2591 resource_list_init(struct resource_list *rl)
2592 {
2593 	STAILQ_INIT(rl);
2594 }
2595 
2596 /**
2597  * @brief Reclaim memory used by a resource list.
2598  *
2599  * This function frees the memory for all resource entries on the list
2600  * (if any).
2601  *
2602  * @param rl		the resource list to free
2603  */
2604 void
2605 resource_list_free(struct resource_list *rl)
2606 {
2607 	struct resource_list_entry *rle;
2608 
2609 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2610 		if (rle->res)
2611 			panic("resource_list_free: resource entry is busy");
2612 		STAILQ_REMOVE_HEAD(rl, link);
2613 		free(rle, M_BUS);
2614 	}
2615 }
2616 
2617 /**
2618  * @brief Add a resource entry.
2619  *
2620  * This function adds a resource entry using the given @p type, @p
2621  * start, @p end and @p count values. A rid value is chosen by
2622  * searching sequentially for the first unused rid starting at zero.
2623  *
2624  * @param rl		the resource list to edit
2625  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2626  * @param start		the start address of the resource
2627  * @param end		the end address of the resource
2628  * @param count		XXX end-start+1
2629  */
2630 int
2631 resource_list_add_next(struct resource_list *rl, int type, u_long start,
2632     u_long end, u_long count)
2633 {
2634 	int rid;
2635 
2636 	rid = 0;
2637 	while (resource_list_find(rl, type, rid) != NULL)
2638 		rid++;
2639 	resource_list_add(rl, type, rid, start, end, count);
2640 	return (rid);
2641 }
2642 
2643 /**
2644  * @brief Add or modify a resource entry.
2645  *
2646  * If an existing entry exists with the same type and rid, it will be
2647  * modified using the given values of @p start, @p end and @p
2648  * count. If no entry exists, a new one will be created using the
2649  * given values.  The resource list entry that matches is then returned.
2650  *
2651  * @param rl		the resource list to edit
2652  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2653  * @param rid		the resource identifier
2654  * @param start		the start address of the resource
2655  * @param end		the end address of the resource
2656  * @param count		XXX end-start+1
2657  */
2658 struct resource_list_entry *
2659 resource_list_add(struct resource_list *rl, int type, int rid,
2660     u_long start, u_long end, u_long count)
2661 {
2662 	struct resource_list_entry *rle;
2663 
2664 	rle = resource_list_find(rl, type, rid);
2665 	if (!rle) {
2666 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
2667 		    M_NOWAIT);
2668 		if (!rle)
2669 			panic("resource_list_add: can't record entry");
2670 		STAILQ_INSERT_TAIL(rl, rle, link);
2671 		rle->type = type;
2672 		rle->rid = rid;
2673 		rle->res = NULL;
2674 	}
2675 
2676 	if (rle->res)
2677 		panic("resource_list_add: resource entry is busy");
2678 
2679 	rle->start = start;
2680 	rle->end = end;
2681 	rle->count = count;
2682 	return (rle);
2683 }
2684 
2685 /**
2686  * @brief Find a resource entry by type and rid.
2687  *
2688  * @param rl		the resource list to search
2689  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2690  * @param rid		the resource identifier
2691  *
2692  * @returns the resource entry pointer or NULL if there is no such
2693  * entry.
2694  */
2695 struct resource_list_entry *
2696 resource_list_find(struct resource_list *rl, int type, int rid)
2697 {
2698 	struct resource_list_entry *rle;
2699 
2700 	STAILQ_FOREACH(rle, rl, link) {
2701 		if (rle->type == type && rle->rid == rid)
2702 			return (rle);
2703 	}
2704 	return (NULL);
2705 }
2706 
2707 /**
2708  * @brief Delete a resource entry.
2709  *
2710  * @param rl		the resource list to edit
2711  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2712  * @param rid		the resource identifier
2713  */
2714 void
2715 resource_list_delete(struct resource_list *rl, int type, int rid)
2716 {
2717 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
2718 
2719 	if (rle) {
2720 		if (rle->res != NULL)
2721 			panic("resource_list_delete: resource has not been released");
2722 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
2723 		free(rle, M_BUS);
2724 	}
2725 }
2726 
2727 /**
2728  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
2729  *
2730  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
2731  * and passing the allocation up to the parent of @p bus. This assumes
2732  * that the first entry of @c device_get_ivars(child) is a struct
2733  * resource_list. This also handles 'passthrough' allocations where a
2734  * child is a remote descendant of bus by passing the allocation up to
2735  * the parent of bus.
2736  *
2737  * Typically, a bus driver would store a list of child resources
2738  * somewhere in the child device's ivars (see device_get_ivars()) and
2739  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
2740  * then call resource_list_alloc() to perform the allocation.
2741  *
2742  * @param rl		the resource list to allocate from
2743  * @param bus		the parent device of @p child
2744  * @param child		the device which is requesting an allocation
2745  * @param type		the type of resource to allocate
2746  * @param rid		a pointer to the resource identifier
2747  * @param start		hint at the start of the resource range - pass
2748  *			@c 0UL for any start address
2749  * @param end		hint at the end of the resource range - pass
2750  *			@c ~0UL for any end address
2751  * @param count		hint at the size of range required - pass @c 1
2752  *			for any size
2753  * @param flags		any extra flags to control the resource
2754  *			allocation - see @c RF_XXX flags in
2755  *			<sys/rman.h> for details
2756  *
2757  * @returns		the resource which was allocated or @c NULL if no
2758  *			resource could be allocated
2759  */
2760 struct resource *
2761 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
2762     int type, int *rid, u_long start, u_long end, u_long count, u_int flags)
2763 {
2764 	struct resource_list_entry *rle = NULL;
2765 	int passthrough = (device_get_parent(child) != bus);
2766 	int isdefault = (start == 0UL && end == ~0UL);
2767 
2768 	if (passthrough) {
2769 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2770 		    type, rid, start, end, count, flags));
2771 	}
2772 
2773 	rle = resource_list_find(rl, type, *rid);
2774 
2775 	if (!rle)
2776 		return (NULL);		/* no resource of that type/rid */
2777 
2778 	if (rle->res)
2779 		panic("resource_list_alloc: resource entry is busy");
2780 
2781 	if (isdefault) {
2782 		start = rle->start;
2783 		count = ulmax(count, rle->count);
2784 		end = ulmax(rle->end, start + count - 1);
2785 	}
2786 
2787 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
2788 	    type, rid, start, end, count, flags);
2789 
2790 	/*
2791 	 * Record the new range.
2792 	 */
2793 	if (rle->res) {
2794 		rle->start = rman_get_start(rle->res);
2795 		rle->end = rman_get_end(rle->res);
2796 		rle->count = count;
2797 	}
2798 
2799 	return (rle->res);
2800 }
2801 
2802 /**
2803  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
2804  *
2805  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
2806  * used with resource_list_alloc().
2807  *
2808  * @param rl		the resource list which was allocated from
2809  * @param bus		the parent device of @p child
2810  * @param child		the device which is requesting a release
2811  * @param type		the type of resource to allocate
2812  * @param rid		the resource identifier
2813  * @param res		the resource to release
2814  *
2815  * @retval 0		success
2816  * @retval non-zero	a standard unix error code indicating what
2817  *			error condition prevented the operation
2818  */
2819 int
2820 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
2821     int type, int rid, struct resource *res)
2822 {
2823 	struct resource_list_entry *rle = NULL;
2824 	int passthrough = (device_get_parent(child) != bus);
2825 	int error;
2826 
2827 	if (passthrough) {
2828 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2829 		    type, rid, res));
2830 	}
2831 
2832 	rle = resource_list_find(rl, type, rid);
2833 
2834 	if (!rle)
2835 		panic("resource_list_release: can't find resource");
2836 	if (!rle->res)
2837 		panic("resource_list_release: resource entry is not busy");
2838 
2839 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
2840 	    type, rid, res);
2841 	if (error)
2842 		return (error);
2843 
2844 	rle->res = NULL;
2845 	return (0);
2846 }
2847 
2848 /**
2849  * @brief Print a description of resources in a resource list
2850  *
2851  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
2852  * The name is printed if at least one resource of the given type is available.
2853  * The format is used to print resource start and end.
2854  *
2855  * @param rl		the resource list to print
2856  * @param name		the name of @p type, e.g. @c "memory"
2857  * @param type		type type of resource entry to print
2858  * @param format	printf(9) format string to print resource
2859  *			start and end values
2860  *
2861  * @returns		the number of characters printed
2862  */
2863 int
2864 resource_list_print_type(struct resource_list *rl, const char *name, int type,
2865     const char *format)
2866 {
2867 	struct resource_list_entry *rle;
2868 	int printed, retval;
2869 
2870 	printed = 0;
2871 	retval = 0;
2872 	/* Yes, this is kinda cheating */
2873 	STAILQ_FOREACH(rle, rl, link) {
2874 		if (rle->type == type) {
2875 			if (printed == 0)
2876 				retval += printf(" %s ", name);
2877 			else
2878 				retval += printf(",");
2879 			printed++;
2880 			retval += printf(format, rle->start);
2881 			if (rle->count > 1) {
2882 				retval += printf("-");
2883 				retval += printf(format, rle->start +
2884 						 rle->count - 1);
2885 			}
2886 		}
2887 	}
2888 	return (retval);
2889 }
2890 
2891 /**
2892  * @brief Releases all the resources in a list.
2893  *
2894  * @param rl		The resource list to purge.
2895  *
2896  * @returns		nothing
2897  */
2898 void
2899 resource_list_purge(struct resource_list *rl)
2900 {
2901 	struct resource_list_entry *rle;
2902 
2903 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2904 		if (rle->res)
2905 			bus_release_resource(rman_get_device(rle->res),
2906 			    rle->type, rle->rid, rle->res);
2907 		STAILQ_REMOVE_HEAD(rl, link);
2908 		free(rle, M_BUS);
2909 	}
2910 }
2911 
2912 device_t
2913 bus_generic_add_child(device_t dev, int order, const char *name, int unit)
2914 {
2915 
2916 	return (device_add_child_ordered(dev, order, name, unit));
2917 }
2918 
2919 /**
2920  * @brief Helper function for implementing DEVICE_PROBE()
2921  *
2922  * This function can be used to help implement the DEVICE_PROBE() for
2923  * a bus (i.e. a device which has other devices attached to it). It
2924  * calls the DEVICE_IDENTIFY() method of each driver in the device's
2925  * devclass.
2926  */
2927 int
2928 bus_generic_probe(device_t dev)
2929 {
2930 	devclass_t dc = dev->devclass;
2931 	driverlink_t dl;
2932 
2933 	TAILQ_FOREACH(dl, &dc->drivers, link) {
2934 		DEVICE_IDENTIFY(dl->driver, dev);
2935 	}
2936 
2937 	return (0);
2938 }
2939 
2940 /**
2941  * @brief Helper function for implementing DEVICE_ATTACH()
2942  *
2943  * This function can be used to help implement the DEVICE_ATTACH() for
2944  * a bus. It calls device_probe_and_attach() for each of the device's
2945  * children.
2946  */
2947 int
2948 bus_generic_attach(device_t dev)
2949 {
2950 	device_t child;
2951 
2952 	TAILQ_FOREACH(child, &dev->children, link) {
2953 		device_probe_and_attach(child);
2954 	}
2955 
2956 	return (0);
2957 }
2958 
2959 /**
2960  * @brief Helper function for implementing DEVICE_DETACH()
2961  *
2962  * This function can be used to help implement the DEVICE_DETACH() for
2963  * a bus. It calls device_detach() for each of the device's
2964  * children.
2965  */
2966 int
2967 bus_generic_detach(device_t dev)
2968 {
2969 	device_t child;
2970 	int error;
2971 
2972 	if (dev->state != DS_ATTACHED)
2973 		return (EBUSY);
2974 
2975 	TAILQ_FOREACH(child, &dev->children, link) {
2976 		if ((error = device_detach(child)) != 0)
2977 			return (error);
2978 	}
2979 
2980 	return (0);
2981 }
2982 
2983 /**
2984  * @brief Helper function for implementing DEVICE_SHUTDOWN()
2985  *
2986  * This function can be used to help implement the DEVICE_SHUTDOWN()
2987  * for a bus. It calls device_shutdown() for each of the device's
2988  * children.
2989  */
2990 int
2991 bus_generic_shutdown(device_t dev)
2992 {
2993 	device_t child;
2994 
2995 	TAILQ_FOREACH(child, &dev->children, link) {
2996 		device_shutdown(child);
2997 	}
2998 
2999 	return (0);
3000 }
3001 
3002 /**
3003  * @brief Helper function for implementing DEVICE_SUSPEND()
3004  *
3005  * This function can be used to help implement the DEVICE_SUSPEND()
3006  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3007  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3008  * operation is aborted and any devices which were suspended are
3009  * resumed immediately by calling their DEVICE_RESUME() methods.
3010  */
3011 int
3012 bus_generic_suspend(device_t dev)
3013 {
3014 	int		error;
3015 	device_t	child, child2;
3016 
3017 	TAILQ_FOREACH(child, &dev->children, link) {
3018 		error = DEVICE_SUSPEND(child);
3019 		if (error) {
3020 			for (child2 = TAILQ_FIRST(&dev->children);
3021 			     child2 && child2 != child;
3022 			     child2 = TAILQ_NEXT(child2, link))
3023 				DEVICE_RESUME(child2);
3024 			return (error);
3025 		}
3026 	}
3027 	return (0);
3028 }
3029 
3030 /**
3031  * @brief Helper function for implementing DEVICE_RESUME()
3032  *
3033  * This function can be used to help implement the DEVICE_RESUME() for
3034  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3035  */
3036 int
3037 bus_generic_resume(device_t dev)
3038 {
3039 	device_t	child;
3040 
3041 	TAILQ_FOREACH(child, &dev->children, link) {
3042 		DEVICE_RESUME(child);
3043 		/* if resume fails, there's nothing we can usefully do... */
3044 	}
3045 	return (0);
3046 }
3047 
3048 /**
3049  * @brief Helper function for implementing BUS_PRINT_CHILD().
3050  *
3051  * This function prints the first part of the ascii representation of
3052  * @p child, including its name, unit and description (if any - see
3053  * device_set_desc()).
3054  *
3055  * @returns the number of characters printed
3056  */
3057 int
3058 bus_print_child_header(device_t dev, device_t child)
3059 {
3060 	int	retval = 0;
3061 
3062 	if (device_get_desc(child)) {
3063 		retval += device_printf(child, "<%s>", device_get_desc(child));
3064 	} else {
3065 		retval += printf("%s", device_get_nameunit(child));
3066 	}
3067 
3068 	return (retval);
3069 }
3070 
3071 /**
3072  * @brief Helper function for implementing BUS_PRINT_CHILD().
3073  *
3074  * This function prints the last part of the ascii representation of
3075  * @p child, which consists of the string @c " on " followed by the
3076  * name and unit of the @p dev.
3077  *
3078  * @returns the number of characters printed
3079  */
3080 int
3081 bus_print_child_footer(device_t dev, device_t child)
3082 {
3083 	return (printf(" on %s\n", device_get_nameunit(dev)));
3084 }
3085 
3086 /**
3087  * @brief Helper function for implementing BUS_PRINT_CHILD().
3088  *
3089  * This function simply calls bus_print_child_header() followed by
3090  * bus_print_child_footer().
3091  *
3092  * @returns the number of characters printed
3093  */
3094 int
3095 bus_generic_print_child(device_t dev, device_t child)
3096 {
3097 	int	retval = 0;
3098 
3099 	retval += bus_print_child_header(dev, child);
3100 	retval += bus_print_child_footer(dev, child);
3101 
3102 	return (retval);
3103 }
3104 
3105 /**
3106  * @brief Stub function for implementing BUS_READ_IVAR().
3107  *
3108  * @returns ENOENT
3109  */
3110 int
3111 bus_generic_read_ivar(device_t dev, device_t child, int index,
3112     uintptr_t * result)
3113 {
3114 	return (ENOENT);
3115 }
3116 
3117 /**
3118  * @brief Stub function for implementing BUS_WRITE_IVAR().
3119  *
3120  * @returns ENOENT
3121  */
3122 int
3123 bus_generic_write_ivar(device_t dev, device_t child, int index,
3124     uintptr_t value)
3125 {
3126 	return (ENOENT);
3127 }
3128 
3129 /**
3130  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
3131  *
3132  * @returns NULL
3133  */
3134 struct resource_list *
3135 bus_generic_get_resource_list(device_t dev, device_t child)
3136 {
3137 	return (NULL);
3138 }
3139 
3140 /**
3141  * @brief Helper function for implementing BUS_DRIVER_ADDED().
3142  *
3143  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
3144  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
3145  * and then calls device_probe_and_attach() for each unattached child.
3146  */
3147 void
3148 bus_generic_driver_added(device_t dev, driver_t *driver)
3149 {
3150 	device_t child;
3151 
3152 	DEVICE_IDENTIFY(driver, dev);
3153 	TAILQ_FOREACH(child, &dev->children, link) {
3154 		if (child->state == DS_NOTPRESENT ||
3155 		    (child->flags & DF_REBID))
3156 			device_probe_and_attach(child);
3157 	}
3158 }
3159 
3160 /**
3161  * @brief Helper function for implementing BUS_SETUP_INTR().
3162  *
3163  * This simple implementation of BUS_SETUP_INTR() simply calls the
3164  * BUS_SETUP_INTR() method of the parent of @p dev.
3165  */
3166 int
3167 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
3168     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
3169     void **cookiep)
3170 {
3171 	/* Propagate up the bus hierarchy until someone handles it. */
3172 	if (dev->parent)
3173 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
3174 		    filter, intr, arg, cookiep));
3175 	return (EINVAL);
3176 }
3177 
3178 /**
3179  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
3180  *
3181  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
3182  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
3183  */
3184 int
3185 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
3186     void *cookie)
3187 {
3188 	/* Propagate up the bus hierarchy until someone handles it. */
3189 	if (dev->parent)
3190 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
3191 	return (EINVAL);
3192 }
3193 
3194 /**
3195  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3196  *
3197  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
3198  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
3199  */
3200 struct resource *
3201 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
3202     u_long start, u_long end, u_long count, u_int flags)
3203 {
3204 	/* Propagate up the bus hierarchy until someone handles it. */
3205 	if (dev->parent)
3206 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
3207 		    start, end, count, flags));
3208 	return (NULL);
3209 }
3210 
3211 /**
3212  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3213  *
3214  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
3215  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
3216  */
3217 int
3218 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
3219     struct resource *r)
3220 {
3221 	/* Propagate up the bus hierarchy until someone handles it. */
3222 	if (dev->parent)
3223 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
3224 		    r));
3225 	return (EINVAL);
3226 }
3227 
3228 /**
3229  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
3230  *
3231  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
3232  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
3233  */
3234 int
3235 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
3236     struct resource *r)
3237 {
3238 	/* Propagate up the bus hierarchy until someone handles it. */
3239 	if (dev->parent)
3240 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
3241 		    r));
3242 	return (EINVAL);
3243 }
3244 
3245 /**
3246  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
3247  *
3248  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
3249  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
3250  */
3251 int
3252 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
3253     int rid, struct resource *r)
3254 {
3255 	/* Propagate up the bus hierarchy until someone handles it. */
3256 	if (dev->parent)
3257 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
3258 		    r));
3259 	return (EINVAL);
3260 }
3261 
3262 /**
3263  * @brief Helper function for implementing BUS_BIND_INTR().
3264  *
3265  * This simple implementation of BUS_BIND_INTR() simply calls the
3266  * BUS_BIND_INTR() method of the parent of @p dev.
3267  */
3268 int
3269 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
3270     int cpu)
3271 {
3272 
3273 	/* Propagate up the bus hierarchy until someone handles it. */
3274 	if (dev->parent)
3275 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
3276 	return (EINVAL);
3277 }
3278 
3279 /**
3280  * @brief Helper function for implementing BUS_CONFIG_INTR().
3281  *
3282  * This simple implementation of BUS_CONFIG_INTR() simply calls the
3283  * BUS_CONFIG_INTR() method of the parent of @p dev.
3284  */
3285 int
3286 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
3287     enum intr_polarity pol)
3288 {
3289 
3290 	/* Propagate up the bus hierarchy until someone handles it. */
3291 	if (dev->parent)
3292 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
3293 	return (EINVAL);
3294 }
3295 
3296 /**
3297  * @brief Helper function for implementing BUS_GET_DMA_TAG().
3298  *
3299  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
3300  * BUS_GET_DMA_TAG() method of the parent of @p dev.
3301  */
3302 bus_dma_tag_t
3303 bus_generic_get_dma_tag(device_t dev, device_t child)
3304 {
3305 
3306 	/* Propagate up the bus hierarchy until someone handles it. */
3307 	if (dev->parent != NULL)
3308 		return (BUS_GET_DMA_TAG(dev->parent, child));
3309 	return (NULL);
3310 }
3311 
3312 /**
3313  * @brief Helper function for implementing BUS_GET_RESOURCE().
3314  *
3315  * This implementation of BUS_GET_RESOURCE() uses the
3316  * resource_list_find() function to do most of the work. It calls
3317  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3318  * search.
3319  */
3320 int
3321 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
3322     u_long *startp, u_long *countp)
3323 {
3324 	struct resource_list *		rl = NULL;
3325 	struct resource_list_entry *	rle = NULL;
3326 
3327 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3328 	if (!rl)
3329 		return (EINVAL);
3330 
3331 	rle = resource_list_find(rl, type, rid);
3332 	if (!rle)
3333 		return (ENOENT);
3334 
3335 	if (startp)
3336 		*startp = rle->start;
3337 	if (countp)
3338 		*countp = rle->count;
3339 
3340 	return (0);
3341 }
3342 
3343 /**
3344  * @brief Helper function for implementing BUS_SET_RESOURCE().
3345  *
3346  * This implementation of BUS_SET_RESOURCE() uses the
3347  * resource_list_add() function to do most of the work. It calls
3348  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3349  * edit.
3350  */
3351 int
3352 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
3353     u_long start, u_long count)
3354 {
3355 	struct resource_list *		rl = NULL;
3356 
3357 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3358 	if (!rl)
3359 		return (EINVAL);
3360 
3361 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
3362 
3363 	return (0);
3364 }
3365 
3366 /**
3367  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
3368  *
3369  * This implementation of BUS_DELETE_RESOURCE() uses the
3370  * resource_list_delete() function to do most of the work. It calls
3371  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3372  * edit.
3373  */
3374 void
3375 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
3376 {
3377 	struct resource_list *		rl = NULL;
3378 
3379 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3380 	if (!rl)
3381 		return;
3382 
3383 	resource_list_delete(rl, type, rid);
3384 
3385 	return;
3386 }
3387 
3388 /**
3389  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3390  *
3391  * This implementation of BUS_RELEASE_RESOURCE() uses the
3392  * resource_list_release() function to do most of the work. It calls
3393  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3394  */
3395 int
3396 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
3397     int rid, struct resource *r)
3398 {
3399 	struct resource_list *		rl = NULL;
3400 
3401 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3402 	if (!rl)
3403 		return (EINVAL);
3404 
3405 	return (resource_list_release(rl, dev, child, type, rid, r));
3406 }
3407 
3408 /**
3409  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3410  *
3411  * This implementation of BUS_ALLOC_RESOURCE() uses the
3412  * resource_list_alloc() function to do most of the work. It calls
3413  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
3414  */
3415 struct resource *
3416 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
3417     int *rid, u_long start, u_long end, u_long count, u_int flags)
3418 {
3419 	struct resource_list *		rl = NULL;
3420 
3421 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3422 	if (!rl)
3423 		return (NULL);
3424 
3425 	return (resource_list_alloc(rl, dev, child, type, rid,
3426 	    start, end, count, flags));
3427 }
3428 
3429 /**
3430  * @brief Helper function for implementing BUS_CHILD_PRESENT().
3431  *
3432  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
3433  * BUS_CHILD_PRESENT() method of the parent of @p dev.
3434  */
3435 int
3436 bus_generic_child_present(device_t dev, device_t child)
3437 {
3438 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
3439 }
3440 
3441 /*
3442  * Some convenience functions to make it easier for drivers to use the
3443  * resource-management functions.  All these really do is hide the
3444  * indirection through the parent's method table, making for slightly
3445  * less-wordy code.  In the future, it might make sense for this code
3446  * to maintain some sort of a list of resources allocated by each device.
3447  */
3448 
3449 int
3450 bus_alloc_resources(device_t dev, struct resource_spec *rs,
3451     struct resource **res)
3452 {
3453 	int i;
3454 
3455 	for (i = 0; rs[i].type != -1; i++)
3456 		res[i] = NULL;
3457 	for (i = 0; rs[i].type != -1; i++) {
3458 		res[i] = bus_alloc_resource_any(dev,
3459 		    rs[i].type, &rs[i].rid, rs[i].flags);
3460 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
3461 			bus_release_resources(dev, rs, res);
3462 			return (ENXIO);
3463 		}
3464 	}
3465 	return (0);
3466 }
3467 
3468 void
3469 bus_release_resources(device_t dev, const struct resource_spec *rs,
3470     struct resource **res)
3471 {
3472 	int i;
3473 
3474 	for (i = 0; rs[i].type != -1; i++)
3475 		if (res[i] != NULL) {
3476 			bus_release_resource(
3477 			    dev, rs[i].type, rs[i].rid, res[i]);
3478 			res[i] = NULL;
3479 		}
3480 }
3481 
3482 /**
3483  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
3484  *
3485  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
3486  * parent of @p dev.
3487  */
3488 struct resource *
3489 bus_alloc_resource(device_t dev, int type, int *rid, u_long start, u_long end,
3490     u_long count, u_int flags)
3491 {
3492 	if (dev->parent == NULL)
3493 		return (NULL);
3494 	return (BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
3495 	    count, flags));
3496 }
3497 
3498 /**
3499  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
3500  *
3501  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
3502  * parent of @p dev.
3503  */
3504 int
3505 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
3506 {
3507 	if (dev->parent == NULL)
3508 		return (EINVAL);
3509 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3510 }
3511 
3512 /**
3513  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
3514  *
3515  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
3516  * parent of @p dev.
3517  */
3518 int
3519 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
3520 {
3521 	if (dev->parent == NULL)
3522 		return (EINVAL);
3523 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
3524 }
3525 
3526 /**
3527  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
3528  *
3529  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
3530  * parent of @p dev.
3531  */
3532 int
3533 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
3534 {
3535 	if (dev->parent == NULL)
3536 		return (EINVAL);
3537 	return (BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r));
3538 }
3539 
3540 /**
3541  * @brief Wrapper function for BUS_SETUP_INTR().
3542  *
3543  * This function simply calls the BUS_SETUP_INTR() method of the
3544  * parent of @p dev.
3545  */
3546 int
3547 bus_setup_intr(device_t dev, struct resource *r, int flags,
3548     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
3549 {
3550 	int error;
3551 
3552 	if (dev->parent == NULL)
3553 		return (EINVAL);
3554 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
3555 	    arg, cookiep);
3556 	if (error != 0)
3557 		return (error);
3558 	if (handler != NULL && !(flags & INTR_MPSAFE))
3559 		device_printf(dev, "[GIANT-LOCKED]\n");
3560 	if (bootverbose && (flags & INTR_MPSAFE))
3561 		device_printf(dev, "[MPSAFE]\n");
3562 	if (filter != NULL) {
3563 		if (handler == NULL)
3564 			device_printf(dev, "[FILTER]\n");
3565 		else
3566 			device_printf(dev, "[FILTER+ITHREAD]\n");
3567 	} else
3568 		device_printf(dev, "[ITHREAD]\n");
3569 	return (0);
3570 }
3571 
3572 /**
3573  * @brief Wrapper function for BUS_TEARDOWN_INTR().
3574  *
3575  * This function simply calls the BUS_TEARDOWN_INTR() method of the
3576  * parent of @p dev.
3577  */
3578 int
3579 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
3580 {
3581 	if (dev->parent == NULL)
3582 		return (EINVAL);
3583 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
3584 }
3585 
3586 /**
3587  * @brief Wrapper function for BUS_BIND_INTR().
3588  *
3589  * This function simply calls the BUS_BIND_INTR() method of the
3590  * parent of @p dev.
3591  */
3592 int
3593 bus_bind_intr(device_t dev, struct resource *r, int cpu)
3594 {
3595 	if (dev->parent == NULL)
3596 		return (EINVAL);
3597 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
3598 }
3599 
3600 /**
3601  * @brief Wrapper function for BUS_SET_RESOURCE().
3602  *
3603  * This function simply calls the BUS_SET_RESOURCE() method of the
3604  * parent of @p dev.
3605  */
3606 int
3607 bus_set_resource(device_t dev, int type, int rid,
3608     u_long start, u_long count)
3609 {
3610 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
3611 	    start, count));
3612 }
3613 
3614 /**
3615  * @brief Wrapper function for BUS_GET_RESOURCE().
3616  *
3617  * This function simply calls the BUS_GET_RESOURCE() method of the
3618  * parent of @p dev.
3619  */
3620 int
3621 bus_get_resource(device_t dev, int type, int rid,
3622     u_long *startp, u_long *countp)
3623 {
3624 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3625 	    startp, countp));
3626 }
3627 
3628 /**
3629  * @brief Wrapper function for BUS_GET_RESOURCE().
3630  *
3631  * This function simply calls the BUS_GET_RESOURCE() method of the
3632  * parent of @p dev and returns the start value.
3633  */
3634 u_long
3635 bus_get_resource_start(device_t dev, int type, int rid)
3636 {
3637 	u_long start, count;
3638 	int error;
3639 
3640 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3641 	    &start, &count);
3642 	if (error)
3643 		return (0);
3644 	return (start);
3645 }
3646 
3647 /**
3648  * @brief Wrapper function for BUS_GET_RESOURCE().
3649  *
3650  * This function simply calls the BUS_GET_RESOURCE() method of the
3651  * parent of @p dev and returns the count value.
3652  */
3653 u_long
3654 bus_get_resource_count(device_t dev, int type, int rid)
3655 {
3656 	u_long start, count;
3657 	int error;
3658 
3659 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
3660 	    &start, &count);
3661 	if (error)
3662 		return (0);
3663 	return (count);
3664 }
3665 
3666 /**
3667  * @brief Wrapper function for BUS_DELETE_RESOURCE().
3668  *
3669  * This function simply calls the BUS_DELETE_RESOURCE() method of the
3670  * parent of @p dev.
3671  */
3672 void
3673 bus_delete_resource(device_t dev, int type, int rid)
3674 {
3675 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
3676 }
3677 
3678 /**
3679  * @brief Wrapper function for BUS_CHILD_PRESENT().
3680  *
3681  * This function simply calls the BUS_CHILD_PRESENT() method of the
3682  * parent of @p dev.
3683  */
3684 int
3685 bus_child_present(device_t child)
3686 {
3687 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
3688 }
3689 
3690 /**
3691  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
3692  *
3693  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
3694  * parent of @p dev.
3695  */
3696 int
3697 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
3698 {
3699 	device_t parent;
3700 
3701 	parent = device_get_parent(child);
3702 	if (parent == NULL) {
3703 		*buf = '\0';
3704 		return (0);
3705 	}
3706 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
3707 }
3708 
3709 /**
3710  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
3711  *
3712  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
3713  * parent of @p dev.
3714  */
3715 int
3716 bus_child_location_str(device_t child, char *buf, size_t buflen)
3717 {
3718 	device_t parent;
3719 
3720 	parent = device_get_parent(child);
3721 	if (parent == NULL) {
3722 		*buf = '\0';
3723 		return (0);
3724 	}
3725 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
3726 }
3727 
3728 /**
3729  * @brief Wrapper function for BUS_GET_DMA_TAG().
3730  *
3731  * This function simply calls the BUS_GET_DMA_TAG() method of the
3732  * parent of @p dev.
3733  */
3734 bus_dma_tag_t
3735 bus_get_dma_tag(device_t dev)
3736 {
3737 	device_t parent;
3738 
3739 	parent = device_get_parent(dev);
3740 	if (parent == NULL)
3741 		return (NULL);
3742 	return (BUS_GET_DMA_TAG(parent, dev));
3743 }
3744 
3745 /* Resume all devices and then notify userland that we're up again. */
3746 static int
3747 root_resume(device_t dev)
3748 {
3749 	int error;
3750 
3751 	error = bus_generic_resume(dev);
3752 	if (error == 0)
3753 		devctl_notify("kern", "power", "resume", NULL);
3754 	return (error);
3755 }
3756 
3757 static int
3758 root_print_child(device_t dev, device_t child)
3759 {
3760 	int	retval = 0;
3761 
3762 	retval += bus_print_child_header(dev, child);
3763 	retval += printf("\n");
3764 
3765 	return (retval);
3766 }
3767 
3768 static int
3769 root_setup_intr(device_t dev, device_t child, driver_intr_t *intr, void *arg,
3770     void **cookiep)
3771 {
3772 	/*
3773 	 * If an interrupt mapping gets to here something bad has happened.
3774 	 */
3775 	panic("root_setup_intr");
3776 }
3777 
3778 /*
3779  * If we get here, assume that the device is permanant and really is
3780  * present in the system.  Removable bus drivers are expected to intercept
3781  * this call long before it gets here.  We return -1 so that drivers that
3782  * really care can check vs -1 or some ERRNO returned higher in the food
3783  * chain.
3784  */
3785 static int
3786 root_child_present(device_t dev, device_t child)
3787 {
3788 	return (-1);
3789 }
3790 
3791 static kobj_method_t root_methods[] = {
3792 	/* Device interface */
3793 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
3794 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
3795 	KOBJMETHOD(device_resume,	root_resume),
3796 
3797 	/* Bus interface */
3798 	KOBJMETHOD(bus_print_child,	root_print_child),
3799 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
3800 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
3801 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
3802 	KOBJMETHOD(bus_child_present,	root_child_present),
3803 
3804 	{ 0, 0 }
3805 };
3806 
3807 static driver_t root_driver = {
3808 	"root",
3809 	root_methods,
3810 	1,			/* no softc */
3811 };
3812 
3813 device_t	root_bus;
3814 devclass_t	root_devclass;
3815 
3816 static int
3817 root_bus_module_handler(module_t mod, int what, void* arg)
3818 {
3819 	switch (what) {
3820 	case MOD_LOAD:
3821 		TAILQ_INIT(&bus_data_devices);
3822 		kobj_class_compile((kobj_class_t) &root_driver);
3823 		root_bus = make_device(NULL, "root", 0);
3824 		root_bus->desc = "System root bus";
3825 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
3826 		root_bus->driver = &root_driver;
3827 		root_bus->state = DS_ATTACHED;
3828 		root_devclass = devclass_find_internal("root", NULL, FALSE);
3829 		devinit();
3830 		return (0);
3831 
3832 	case MOD_SHUTDOWN:
3833 		device_shutdown(root_bus);
3834 		return (0);
3835 	default:
3836 		return (EOPNOTSUPP);
3837 	}
3838 
3839 	return (0);
3840 }
3841 
3842 static moduledata_t root_bus_mod = {
3843 	"rootbus",
3844 	root_bus_module_handler,
3845 	0
3846 };
3847 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
3848 
3849 /**
3850  * @brief Automatically configure devices
3851  *
3852  * This function begins the autoconfiguration process by calling
3853  * device_probe_and_attach() for each child of the @c root0 device.
3854  */
3855 void
3856 root_bus_configure(void)
3857 {
3858 	device_t dev;
3859 
3860 	PDEBUG(("."));
3861 
3862 	TAILQ_FOREACH(dev, &root_bus->children, link) {
3863 		device_probe_and_attach(dev);
3864 	}
3865 }
3866 
3867 /**
3868  * @brief Module handler for registering device drivers
3869  *
3870  * This module handler is used to automatically register device
3871  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
3872  * devclass_add_driver() for the driver described by the
3873  * driver_module_data structure pointed to by @p arg
3874  */
3875 int
3876 driver_module_handler(module_t mod, int what, void *arg)
3877 {
3878 	int error;
3879 	struct driver_module_data *dmd;
3880 	devclass_t bus_devclass;
3881 	kobj_class_t driver;
3882 
3883 	dmd = (struct driver_module_data *)arg;
3884 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
3885 	error = 0;
3886 
3887 	switch (what) {
3888 	case MOD_LOAD:
3889 		if (dmd->dmd_chainevh)
3890 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3891 
3892 		driver = dmd->dmd_driver;
3893 		PDEBUG(("Loading module: driver %s on bus %s",
3894 		    DRIVERNAME(driver), dmd->dmd_busname));
3895 		error = devclass_add_driver(bus_devclass, driver);
3896 		if (error)
3897 			break;
3898 
3899 		/*
3900 		 * If the driver has any base classes, make the
3901 		 * devclass inherit from the devclass of the driver's
3902 		 * first base class. This will allow the system to
3903 		 * search for drivers in both devclasses for children
3904 		 * of a device using this driver.
3905 		 */
3906 		if (driver->baseclasses) {
3907 			const char *parentname;
3908 			parentname = driver->baseclasses[0]->name;
3909 			*dmd->dmd_devclass =
3910 				devclass_find_internal(driver->name,
3911 				    parentname, TRUE);
3912 		} else {
3913 			*dmd->dmd_devclass =
3914 				devclass_find_internal(driver->name, NULL, TRUE);
3915 		}
3916 		break;
3917 
3918 	case MOD_UNLOAD:
3919 		PDEBUG(("Unloading module: driver %s from bus %s",
3920 		    DRIVERNAME(dmd->dmd_driver),
3921 		    dmd->dmd_busname));
3922 		error = devclass_delete_driver(bus_devclass,
3923 		    dmd->dmd_driver);
3924 
3925 		if (!error && dmd->dmd_chainevh)
3926 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3927 		break;
3928 	case MOD_QUIESCE:
3929 		PDEBUG(("Quiesce module: driver %s from bus %s",
3930 		    DRIVERNAME(dmd->dmd_driver),
3931 		    dmd->dmd_busname));
3932 		error = devclass_quiesce_driver(bus_devclass,
3933 		    dmd->dmd_driver);
3934 
3935 		if (!error && dmd->dmd_chainevh)
3936 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
3937 		break;
3938 	default:
3939 		error = EOPNOTSUPP;
3940 		break;
3941 	}
3942 
3943 	return (error);
3944 }
3945 
3946 /**
3947  * @brief Enumerate all hinted devices for this bus.
3948  *
3949  * Walks through the hints for this bus and calls the bus_hinted_child
3950  * routine for each one it fines.  It searches first for the specific
3951  * bus that's being probed for hinted children (eg isa0), and then for
3952  * generic children (eg isa).
3953  *
3954  * @param	dev	bus device to enumerate
3955  */
3956 void
3957 bus_enumerate_hinted_children(device_t bus)
3958 {
3959 	int i;
3960 	const char *dname, *busname;
3961 	int dunit;
3962 
3963 	/*
3964 	 * enumerate all devices on the specific bus
3965 	 */
3966 	busname = device_get_nameunit(bus);
3967 	i = 0;
3968 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3969 		BUS_HINTED_CHILD(bus, dname, dunit);
3970 
3971 	/*
3972 	 * and all the generic ones.
3973 	 */
3974 	busname = device_get_name(bus);
3975 	i = 0;
3976 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
3977 		BUS_HINTED_CHILD(bus, dname, dunit);
3978 }
3979 
3980 #ifdef BUS_DEBUG
3981 
3982 /* the _short versions avoid iteration by not calling anything that prints
3983  * more than oneliners. I love oneliners.
3984  */
3985 
3986 static void
3987 print_device_short(device_t dev, int indent)
3988 {
3989 	if (!dev)
3990 		return;
3991 
3992 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
3993 	    dev->unit, dev->desc,
3994 	    (dev->parent? "":"no "),
3995 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
3996 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
3997 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
3998 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
3999 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
4000 	    (dev->flags&DF_REBID? "rebiddable,":""),
4001 	    (dev->ivars? "":"no "),
4002 	    (dev->softc? "":"no "),
4003 	    dev->busy));
4004 }
4005 
4006 static void
4007 print_device(device_t dev, int indent)
4008 {
4009 	if (!dev)
4010 		return;
4011 
4012 	print_device_short(dev, indent);
4013 
4014 	indentprintf(("Parent:\n"));
4015 	print_device_short(dev->parent, indent+1);
4016 	indentprintf(("Driver:\n"));
4017 	print_driver_short(dev->driver, indent+1);
4018 	indentprintf(("Devclass:\n"));
4019 	print_devclass_short(dev->devclass, indent+1);
4020 }
4021 
4022 void
4023 print_device_tree_short(device_t dev, int indent)
4024 /* print the device and all its children (indented) */
4025 {
4026 	device_t child;
4027 
4028 	if (!dev)
4029 		return;
4030 
4031 	print_device_short(dev, indent);
4032 
4033 	TAILQ_FOREACH(child, &dev->children, link) {
4034 		print_device_tree_short(child, indent+1);
4035 	}
4036 }
4037 
4038 void
4039 print_device_tree(device_t dev, int indent)
4040 /* print the device and all its children (indented) */
4041 {
4042 	device_t child;
4043 
4044 	if (!dev)
4045 		return;
4046 
4047 	print_device(dev, indent);
4048 
4049 	TAILQ_FOREACH(child, &dev->children, link) {
4050 		print_device_tree(child, indent+1);
4051 	}
4052 }
4053 
4054 static void
4055 print_driver_short(driver_t *driver, int indent)
4056 {
4057 	if (!driver)
4058 		return;
4059 
4060 	indentprintf(("driver %s: softc size = %zd\n",
4061 	    driver->name, driver->size));
4062 }
4063 
4064 static void
4065 print_driver(driver_t *driver, int indent)
4066 {
4067 	if (!driver)
4068 		return;
4069 
4070 	print_driver_short(driver, indent);
4071 }
4072 
4073 
4074 static void
4075 print_driver_list(driver_list_t drivers, int indent)
4076 {
4077 	driverlink_t driver;
4078 
4079 	TAILQ_FOREACH(driver, &drivers, link) {
4080 		print_driver(driver->driver, indent);
4081 	}
4082 }
4083 
4084 static void
4085 print_devclass_short(devclass_t dc, int indent)
4086 {
4087 	if ( !dc )
4088 		return;
4089 
4090 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
4091 }
4092 
4093 static void
4094 print_devclass(devclass_t dc, int indent)
4095 {
4096 	int i;
4097 
4098 	if ( !dc )
4099 		return;
4100 
4101 	print_devclass_short(dc, indent);
4102 	indentprintf(("Drivers:\n"));
4103 	print_driver_list(dc->drivers, indent+1);
4104 
4105 	indentprintf(("Devices:\n"));
4106 	for (i = 0; i < dc->maxunit; i++)
4107 		if (dc->devices[i])
4108 			print_device(dc->devices[i], indent+1);
4109 }
4110 
4111 void
4112 print_devclass_list_short(void)
4113 {
4114 	devclass_t dc;
4115 
4116 	printf("Short listing of devclasses, drivers & devices:\n");
4117 	TAILQ_FOREACH(dc, &devclasses, link) {
4118 		print_devclass_short(dc, 0);
4119 	}
4120 }
4121 
4122 void
4123 print_devclass_list(void)
4124 {
4125 	devclass_t dc;
4126 
4127 	printf("Full listing of devclasses, drivers & devices:\n");
4128 	TAILQ_FOREACH(dc, &devclasses, link) {
4129 		print_devclass(dc, 0);
4130 	}
4131 }
4132 
4133 #endif
4134 
4135 /*
4136  * User-space access to the device tree.
4137  *
4138  * We implement a small set of nodes:
4139  *
4140  * hw.bus			Single integer read method to obtain the
4141  *				current generation count.
4142  * hw.bus.devices		Reads the entire device tree in flat space.
4143  * hw.bus.rman			Resource manager interface
4144  *
4145  * We might like to add the ability to scan devclasses and/or drivers to
4146  * determine what else is currently loaded/available.
4147  */
4148 
4149 static int
4150 sysctl_bus(SYSCTL_HANDLER_ARGS)
4151 {
4152 	struct u_businfo	ubus;
4153 
4154 	ubus.ub_version = BUS_USER_VERSION;
4155 	ubus.ub_generation = bus_data_generation;
4156 
4157 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
4158 }
4159 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
4160     "bus-related data");
4161 
4162 static int
4163 sysctl_devices(SYSCTL_HANDLER_ARGS)
4164 {
4165 	int			*name = (int *)arg1;
4166 	u_int			namelen = arg2;
4167 	int			index;
4168 	struct device		*dev;
4169 	struct u_device		udev;	/* XXX this is a bit big */
4170 	int			error;
4171 
4172 	if (namelen != 2)
4173 		return (EINVAL);
4174 
4175 	if (bus_data_generation_check(name[0]))
4176 		return (EINVAL);
4177 
4178 	index = name[1];
4179 
4180 	/*
4181 	 * Scan the list of devices, looking for the requested index.
4182 	 */
4183 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
4184 		if (index-- == 0)
4185 			break;
4186 	}
4187 	if (dev == NULL)
4188 		return (ENOENT);
4189 
4190 	/*
4191 	 * Populate the return array.
4192 	 */
4193 	bzero(&udev, sizeof(udev));
4194 	udev.dv_handle = (uintptr_t)dev;
4195 	udev.dv_parent = (uintptr_t)dev->parent;
4196 	if (dev->nameunit != NULL)
4197 		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
4198 	if (dev->desc != NULL)
4199 		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
4200 	if (dev->driver != NULL && dev->driver->name != NULL)
4201 		strlcpy(udev.dv_drivername, dev->driver->name,
4202 		    sizeof(udev.dv_drivername));
4203 	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
4204 	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
4205 	udev.dv_devflags = dev->devflags;
4206 	udev.dv_flags = dev->flags;
4207 	udev.dv_state = dev->state;
4208 	error = SYSCTL_OUT(req, &udev, sizeof(udev));
4209 	return (error);
4210 }
4211 
4212 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
4213     "system device tree");
4214 
4215 int
4216 bus_data_generation_check(int generation)
4217 {
4218 	if (generation != bus_data_generation)
4219 		return (1);
4220 
4221 	/* XXX generate optimised lists here? */
4222 	return (0);
4223 }
4224 
4225 void
4226 bus_data_generation_update(void)
4227 {
4228 	bus_data_generation++;
4229 }
4230 
4231 int
4232 bus_free_resource(device_t dev, int type, struct resource *r)
4233 {
4234 	if (r == NULL)
4235 		return (0);
4236 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
4237 }
4238