xref: /freebsd/sys/kern/subr_bus.c (revision ce3adf4362fcca6a43e500b2531f0038adbfbd21)
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/limits.h>
39 #include <sys/malloc.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/poll.h>
43 #include <sys/proc.h>
44 #include <sys/condvar.h>
45 #include <sys/queue.h>
46 #include <machine/bus.h>
47 #include <sys/rman.h>
48 #include <sys/selinfo.h>
49 #include <sys/signalvar.h>
50 #include <sys/sysctl.h>
51 #include <sys/systm.h>
52 #include <sys/uio.h>
53 #include <sys/bus.h>
54 #include <sys/interrupt.h>
55 
56 #include <net/vnet.h>
57 
58 #include <machine/stdarg.h>
59 
60 #include <vm/uma.h>
61 
62 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW, NULL, NULL);
63 SYSCTL_NODE(, OID_AUTO, dev, CTLFLAG_RW, NULL, NULL);
64 
65 /*
66  * Used to attach drivers to devclasses.
67  */
68 typedef struct driverlink *driverlink_t;
69 struct driverlink {
70 	kobj_class_t	driver;
71 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
72 	int		pass;
73 	TAILQ_ENTRY(driverlink) passlink;
74 };
75 
76 /*
77  * Forward declarations
78  */
79 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
80 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
81 typedef TAILQ_HEAD(device_list, device) device_list_t;
82 
83 struct devclass {
84 	TAILQ_ENTRY(devclass) link;
85 	devclass_t	parent;		/* parent in devclass hierarchy */
86 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
87 	char		*name;
88 	device_t	*devices;	/* array of devices indexed by unit */
89 	int		maxunit;	/* size of devices array */
90 	int		flags;
91 #define DC_HAS_CHILDREN		1
92 
93 	struct sysctl_ctx_list sysctl_ctx;
94 	struct sysctl_oid *sysctl_tree;
95 };
96 
97 /**
98  * @brief Implementation of device.
99  */
100 struct device {
101 	/*
102 	 * A device is a kernel object. The first field must be the
103 	 * current ops table for the object.
104 	 */
105 	KOBJ_FIELDS;
106 
107 	/*
108 	 * Device hierarchy.
109 	 */
110 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
111 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
112 	device_t	parent;		/**< parent of this device  */
113 	device_list_t	children;	/**< list of child devices */
114 
115 	/*
116 	 * Details of this device.
117 	 */
118 	driver_t	*driver;	/**< current driver */
119 	devclass_t	devclass;	/**< current device class */
120 	int		unit;		/**< current unit number */
121 	char*		nameunit;	/**< name+unit e.g. foodev0 */
122 	char*		desc;		/**< driver specific description */
123 	int		busy;		/**< count of calls to device_busy() */
124 	device_state_t	state;		/**< current device state  */
125 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
126 	u_int		flags;		/**< internal device flags  */
127 #define	DF_ENABLED	0x01		/* device should be probed/attached */
128 #define	DF_FIXEDCLASS	0x02		/* devclass specified at create time */
129 #define	DF_WILDCARD	0x04		/* unit was originally wildcard */
130 #define	DF_DESCMALLOCED	0x08		/* description was malloced */
131 #define	DF_QUIET	0x10		/* don't print verbose attach message */
132 #define	DF_DONENOMATCH	0x20		/* don't execute DEVICE_NOMATCH again */
133 #define	DF_EXTERNALSOFTC 0x40		/* softc not allocated by us */
134 #define	DF_REBID	0x80		/* Can rebid after attach */
135 	u_int	order;			/**< order from device_add_child_ordered() */
136 	void	*ivars;			/**< instance variables  */
137 	void	*softc;			/**< current driver's variables  */
138 
139 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
140 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
141 };
142 
143 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
144 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
145 
146 #ifdef BUS_DEBUG
147 
148 static int bus_debug = 1;
149 TUNABLE_INT("bus.debug", &bus_debug);
150 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RW, &bus_debug, 0,
151     "Debug bus code");
152 
153 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
154 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
155 #define DRIVERNAME(d)	((d)? d->name : "no driver")
156 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
157 
158 /**
159  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
160  * prevent syslog from deleting initial spaces
161  */
162 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
163 
164 static void print_device_short(device_t dev, int indent);
165 static void print_device(device_t dev, int indent);
166 void print_device_tree_short(device_t dev, int indent);
167 void print_device_tree(device_t dev, int indent);
168 static void print_driver_short(driver_t *driver, int indent);
169 static void print_driver(driver_t *driver, int indent);
170 static void print_driver_list(driver_list_t drivers, int indent);
171 static void print_devclass_short(devclass_t dc, int indent);
172 static void print_devclass(devclass_t dc, int indent);
173 void print_devclass_list_short(void);
174 void print_devclass_list(void);
175 
176 #else
177 /* Make the compiler ignore the function calls */
178 #define PDEBUG(a)			/* nop */
179 #define DEVICENAME(d)			/* nop */
180 #define DRIVERNAME(d)			/* nop */
181 #define DEVCLANAME(d)			/* nop */
182 
183 #define print_device_short(d,i)		/* nop */
184 #define print_device(d,i)		/* nop */
185 #define print_device_tree_short(d,i)	/* nop */
186 #define print_device_tree(d,i)		/* nop */
187 #define print_driver_short(d,i)		/* nop */
188 #define print_driver(d,i)		/* nop */
189 #define print_driver_list(d,i)		/* nop */
190 #define print_devclass_short(d,i)	/* nop */
191 #define print_devclass(d,i)		/* nop */
192 #define print_devclass_list_short()	/* nop */
193 #define print_devclass_list()		/* nop */
194 #endif
195 
196 /*
197  * dev sysctl tree
198  */
199 
200 enum {
201 	DEVCLASS_SYSCTL_PARENT,
202 };
203 
204 static int
205 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
206 {
207 	devclass_t dc = (devclass_t)arg1;
208 	const char *value;
209 
210 	switch (arg2) {
211 	case DEVCLASS_SYSCTL_PARENT:
212 		value = dc->parent ? dc->parent->name : "";
213 		break;
214 	default:
215 		return (EINVAL);
216 	}
217 	return (SYSCTL_OUT(req, value, strlen(value)));
218 }
219 
220 static void
221 devclass_sysctl_init(devclass_t dc)
222 {
223 
224 	if (dc->sysctl_tree != NULL)
225 		return;
226 	sysctl_ctx_init(&dc->sysctl_ctx);
227 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
228 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
229 	    CTLFLAG_RD, NULL, "");
230 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
231 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
232 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
233 	    "parent class");
234 }
235 
236 enum {
237 	DEVICE_SYSCTL_DESC,
238 	DEVICE_SYSCTL_DRIVER,
239 	DEVICE_SYSCTL_LOCATION,
240 	DEVICE_SYSCTL_PNPINFO,
241 	DEVICE_SYSCTL_PARENT,
242 };
243 
244 static int
245 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
246 {
247 	device_t dev = (device_t)arg1;
248 	const char *value;
249 	char *buf;
250 	int error;
251 
252 	buf = NULL;
253 	switch (arg2) {
254 	case DEVICE_SYSCTL_DESC:
255 		value = dev->desc ? dev->desc : "";
256 		break;
257 	case DEVICE_SYSCTL_DRIVER:
258 		value = dev->driver ? dev->driver->name : "";
259 		break;
260 	case DEVICE_SYSCTL_LOCATION:
261 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
262 		bus_child_location_str(dev, buf, 1024);
263 		break;
264 	case DEVICE_SYSCTL_PNPINFO:
265 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
266 		bus_child_pnpinfo_str(dev, buf, 1024);
267 		break;
268 	case DEVICE_SYSCTL_PARENT:
269 		value = dev->parent ? dev->parent->nameunit : "";
270 		break;
271 	default:
272 		return (EINVAL);
273 	}
274 	error = SYSCTL_OUT(req, value, strlen(value));
275 	if (buf != NULL)
276 		free(buf, M_BUS);
277 	return (error);
278 }
279 
280 static void
281 device_sysctl_init(device_t dev)
282 {
283 	devclass_t dc = dev->devclass;
284 
285 	if (dev->sysctl_tree != NULL)
286 		return;
287 	devclass_sysctl_init(dc);
288 	sysctl_ctx_init(&dev->sysctl_ctx);
289 	dev->sysctl_tree = SYSCTL_ADD_NODE(&dev->sysctl_ctx,
290 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
291 	    dev->nameunit + strlen(dc->name),
292 	    CTLFLAG_RD, NULL, "");
293 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
294 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD,
295 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
296 	    "device description");
297 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
298 	    OID_AUTO, "%driver", CTLTYPE_STRING | CTLFLAG_RD,
299 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
300 	    "device driver name");
301 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
302 	    OID_AUTO, "%location", CTLTYPE_STRING | CTLFLAG_RD,
303 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
304 	    "device location relative to parent");
305 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
306 	    OID_AUTO, "%pnpinfo", CTLTYPE_STRING | CTLFLAG_RD,
307 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
308 	    "device identification");
309 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
310 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
311 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
312 	    "parent device");
313 }
314 
315 static void
316 device_sysctl_update(device_t dev)
317 {
318 	devclass_t dc = dev->devclass;
319 
320 	if (dev->sysctl_tree == NULL)
321 		return;
322 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
323 }
324 
325 static void
326 device_sysctl_fini(device_t dev)
327 {
328 	if (dev->sysctl_tree == NULL)
329 		return;
330 	sysctl_ctx_free(&dev->sysctl_ctx);
331 	dev->sysctl_tree = NULL;
332 }
333 
334 /*
335  * /dev/devctl implementation
336  */
337 
338 /*
339  * This design allows only one reader for /dev/devctl.  This is not desirable
340  * in the long run, but will get a lot of hair out of this implementation.
341  * Maybe we should make this device a clonable device.
342  *
343  * Also note: we specifically do not attach a device to the device_t tree
344  * to avoid potential chicken and egg problems.  One could argue that all
345  * of this belongs to the root node.  One could also further argue that the
346  * sysctl interface that we have not might more properly be an ioctl
347  * interface, but at this stage of the game, I'm not inclined to rock that
348  * boat.
349  *
350  * I'm also not sure that the SIGIO support is done correctly or not, as
351  * I copied it from a driver that had SIGIO support that likely hasn't been
352  * tested since 3.4 or 2.2.8!
353  */
354 
355 /* Deprecated way to adjust queue length */
356 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
357 /* XXX Need to support old-style tunable hw.bus.devctl_disable" */
358 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RW, NULL,
359     0, sysctl_devctl_disable, "I", "devctl disable -- deprecated");
360 
361 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
362 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
363 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
364 TUNABLE_INT("hw.bus.devctl_queue", &devctl_queue_length);
365 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RW, NULL,
366     0, sysctl_devctl_queue, "I", "devctl queue length");
367 
368 static d_open_t		devopen;
369 static d_close_t	devclose;
370 static d_read_t		devread;
371 static d_ioctl_t	devioctl;
372 static d_poll_t		devpoll;
373 
374 static struct cdevsw dev_cdevsw = {
375 	.d_version =	D_VERSION,
376 	.d_flags =	D_NEEDGIANT,
377 	.d_open =	devopen,
378 	.d_close =	devclose,
379 	.d_read =	devread,
380 	.d_ioctl =	devioctl,
381 	.d_poll =	devpoll,
382 	.d_name =	"devctl",
383 };
384 
385 struct dev_event_info
386 {
387 	char *dei_data;
388 	TAILQ_ENTRY(dev_event_info) dei_link;
389 };
390 
391 TAILQ_HEAD(devq, dev_event_info);
392 
393 static struct dev_softc
394 {
395 	int	inuse;
396 	int	nonblock;
397 	int	queued;
398 	struct mtx mtx;
399 	struct cv cv;
400 	struct selinfo sel;
401 	struct devq devq;
402 	struct proc *async_proc;
403 } devsoftc;
404 
405 static struct cdev *devctl_dev;
406 
407 static void
408 devinit(void)
409 {
410 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
411 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
412 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
413 	cv_init(&devsoftc.cv, "dev cv");
414 	TAILQ_INIT(&devsoftc.devq);
415 }
416 
417 static int
418 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
419 {
420 	if (devsoftc.inuse)
421 		return (EBUSY);
422 	/* move to init */
423 	devsoftc.inuse = 1;
424 	devsoftc.nonblock = 0;
425 	devsoftc.async_proc = NULL;
426 	return (0);
427 }
428 
429 static int
430 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
431 {
432 	devsoftc.inuse = 0;
433 	mtx_lock(&devsoftc.mtx);
434 	cv_broadcast(&devsoftc.cv);
435 	mtx_unlock(&devsoftc.mtx);
436 	devsoftc.async_proc = NULL;
437 	return (0);
438 }
439 
440 /*
441  * The read channel for this device is used to report changes to
442  * userland in realtime.  We are required to free the data as well as
443  * the n1 object because we allocate them separately.  Also note that
444  * we return one record at a time.  If you try to read this device a
445  * character at a time, you will lose the rest of the data.  Listening
446  * programs are expected to cope.
447  */
448 static int
449 devread(struct cdev *dev, struct uio *uio, int ioflag)
450 {
451 	struct dev_event_info *n1;
452 	int rv;
453 
454 	mtx_lock(&devsoftc.mtx);
455 	while (TAILQ_EMPTY(&devsoftc.devq)) {
456 		if (devsoftc.nonblock) {
457 			mtx_unlock(&devsoftc.mtx);
458 			return (EAGAIN);
459 		}
460 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
461 		if (rv) {
462 			/*
463 			 * Need to translate ERESTART to EINTR here? -- jake
464 			 */
465 			mtx_unlock(&devsoftc.mtx);
466 			return (rv);
467 		}
468 	}
469 	n1 = TAILQ_FIRST(&devsoftc.devq);
470 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
471 	devsoftc.queued--;
472 	mtx_unlock(&devsoftc.mtx);
473 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
474 	free(n1->dei_data, M_BUS);
475 	free(n1, M_BUS);
476 	return (rv);
477 }
478 
479 static	int
480 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
481 {
482 	switch (cmd) {
483 
484 	case FIONBIO:
485 		if (*(int*)data)
486 			devsoftc.nonblock = 1;
487 		else
488 			devsoftc.nonblock = 0;
489 		return (0);
490 	case FIOASYNC:
491 		if (*(int*)data)
492 			devsoftc.async_proc = td->td_proc;
493 		else
494 			devsoftc.async_proc = NULL;
495 		return (0);
496 
497 		/* (un)Support for other fcntl() calls. */
498 	case FIOCLEX:
499 	case FIONCLEX:
500 	case FIONREAD:
501 	case FIOSETOWN:
502 	case FIOGETOWN:
503 	default:
504 		break;
505 	}
506 	return (ENOTTY);
507 }
508 
509 static	int
510 devpoll(struct cdev *dev, int events, struct thread *td)
511 {
512 	int	revents = 0;
513 
514 	mtx_lock(&devsoftc.mtx);
515 	if (events & (POLLIN | POLLRDNORM)) {
516 		if (!TAILQ_EMPTY(&devsoftc.devq))
517 			revents = events & (POLLIN | POLLRDNORM);
518 		else
519 			selrecord(td, &devsoftc.sel);
520 	}
521 	mtx_unlock(&devsoftc.mtx);
522 
523 	return (revents);
524 }
525 
526 /**
527  * @brief Return whether the userland process is running
528  */
529 boolean_t
530 devctl_process_running(void)
531 {
532 	return (devsoftc.inuse == 1);
533 }
534 
535 /**
536  * @brief Queue data to be read from the devctl device
537  *
538  * Generic interface to queue data to the devctl device.  It is
539  * assumed that @p data is properly formatted.  It is further assumed
540  * that @p data is allocated using the M_BUS malloc type.
541  */
542 void
543 devctl_queue_data_f(char *data, int flags)
544 {
545 	struct dev_event_info *n1 = NULL, *n2 = NULL;
546 	struct proc *p;
547 
548 	if (strlen(data) == 0)
549 		goto out;
550 	if (devctl_queue_length == 0)
551 		goto out;
552 	n1 = malloc(sizeof(*n1), M_BUS, flags);
553 	if (n1 == NULL)
554 		goto out;
555 	n1->dei_data = data;
556 	mtx_lock(&devsoftc.mtx);
557 	if (devctl_queue_length == 0) {
558 		mtx_unlock(&devsoftc.mtx);
559 		free(n1->dei_data, M_BUS);
560 		free(n1, M_BUS);
561 		return;
562 	}
563 	/* Leave at least one spot in the queue... */
564 	while (devsoftc.queued > devctl_queue_length - 1) {
565 		n2 = TAILQ_FIRST(&devsoftc.devq);
566 		TAILQ_REMOVE(&devsoftc.devq, n2, dei_link);
567 		free(n2->dei_data, M_BUS);
568 		free(n2, M_BUS);
569 		devsoftc.queued--;
570 	}
571 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
572 	devsoftc.queued++;
573 	cv_broadcast(&devsoftc.cv);
574 	mtx_unlock(&devsoftc.mtx);
575 	selwakeup(&devsoftc.sel);
576 	p = devsoftc.async_proc;
577 	if (p != NULL) {
578 		PROC_LOCK(p);
579 		kern_psignal(p, SIGIO);
580 		PROC_UNLOCK(p);
581 	}
582 	return;
583 out:
584 	/*
585 	 * We have to free data on all error paths since the caller
586 	 * assumes it will be free'd when this item is dequeued.
587 	 */
588 	free(data, M_BUS);
589 	return;
590 }
591 
592 void
593 devctl_queue_data(char *data)
594 {
595 
596 	devctl_queue_data_f(data, M_NOWAIT);
597 }
598 
599 /**
600  * @brief Send a 'notification' to userland, using standard ways
601  */
602 void
603 devctl_notify_f(const char *system, const char *subsystem, const char *type,
604     const char *data, int flags)
605 {
606 	int len = 0;
607 	char *msg;
608 
609 	if (system == NULL)
610 		return;		/* BOGUS!  Must specify system. */
611 	if (subsystem == NULL)
612 		return;		/* BOGUS!  Must specify subsystem. */
613 	if (type == NULL)
614 		return;		/* BOGUS!  Must specify type. */
615 	len += strlen(" system=") + strlen(system);
616 	len += strlen(" subsystem=") + strlen(subsystem);
617 	len += strlen(" type=") + strlen(type);
618 	/* add in the data message plus newline. */
619 	if (data != NULL)
620 		len += strlen(data);
621 	len += 3;	/* '!', '\n', and NUL */
622 	msg = malloc(len, M_BUS, flags);
623 	if (msg == NULL)
624 		return;		/* Drop it on the floor */
625 	if (data != NULL)
626 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
627 		    system, subsystem, type, data);
628 	else
629 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
630 		    system, subsystem, type);
631 	devctl_queue_data_f(msg, flags);
632 }
633 
634 void
635 devctl_notify(const char *system, const char *subsystem, const char *type,
636     const char *data)
637 {
638 
639 	devctl_notify_f(system, subsystem, type, data, M_NOWAIT);
640 }
641 
642 /*
643  * Common routine that tries to make sending messages as easy as possible.
644  * We allocate memory for the data, copy strings into that, but do not
645  * free it unless there's an error.  The dequeue part of the driver should
646  * free the data.  We don't send data when the device is disabled.  We do
647  * send data, even when we have no listeners, because we wish to avoid
648  * races relating to startup and restart of listening applications.
649  *
650  * devaddq is designed to string together the type of event, with the
651  * object of that event, plus the plug and play info and location info
652  * for that event.  This is likely most useful for devices, but less
653  * useful for other consumers of this interface.  Those should use
654  * the devctl_queue_data() interface instead.
655  */
656 static void
657 devaddq(const char *type, const char *what, device_t dev)
658 {
659 	char *data = NULL;
660 	char *loc = NULL;
661 	char *pnp = NULL;
662 	const char *parstr;
663 
664 	if (!devctl_queue_length)/* Rare race, but lost races safely discard */
665 		return;
666 	data = malloc(1024, M_BUS, M_NOWAIT);
667 	if (data == NULL)
668 		goto bad;
669 
670 	/* get the bus specific location of this device */
671 	loc = malloc(1024, M_BUS, M_NOWAIT);
672 	if (loc == NULL)
673 		goto bad;
674 	*loc = '\0';
675 	bus_child_location_str(dev, loc, 1024);
676 
677 	/* Get the bus specific pnp info of this device */
678 	pnp = malloc(1024, M_BUS, M_NOWAIT);
679 	if (pnp == NULL)
680 		goto bad;
681 	*pnp = '\0';
682 	bus_child_pnpinfo_str(dev, pnp, 1024);
683 
684 	/* Get the parent of this device, or / if high enough in the tree. */
685 	if (device_get_parent(dev) == NULL)
686 		parstr = ".";	/* Or '/' ? */
687 	else
688 		parstr = device_get_nameunit(device_get_parent(dev));
689 	/* String it all together. */
690 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
691 	  parstr);
692 	free(loc, M_BUS);
693 	free(pnp, M_BUS);
694 	devctl_queue_data(data);
695 	return;
696 bad:
697 	free(pnp, M_BUS);
698 	free(loc, M_BUS);
699 	free(data, M_BUS);
700 	return;
701 }
702 
703 /*
704  * A device was added to the tree.  We are called just after it successfully
705  * attaches (that is, probe and attach success for this device).  No call
706  * is made if a device is merely parented into the tree.  See devnomatch
707  * if probe fails.  If attach fails, no notification is sent (but maybe
708  * we should have a different message for this).
709  */
710 static void
711 devadded(device_t dev)
712 {
713 	devaddq("+", device_get_nameunit(dev), dev);
714 }
715 
716 /*
717  * A device was removed from the tree.  We are called just before this
718  * happens.
719  */
720 static void
721 devremoved(device_t dev)
722 {
723 	devaddq("-", device_get_nameunit(dev), dev);
724 }
725 
726 /*
727  * Called when there's no match for this device.  This is only called
728  * the first time that no match happens, so we don't keep getting this
729  * message.  Should that prove to be undesirable, we can change it.
730  * This is called when all drivers that can attach to a given bus
731  * decline to accept this device.  Other errors may not be detected.
732  */
733 static void
734 devnomatch(device_t dev)
735 {
736 	devaddq("?", "", dev);
737 }
738 
739 static int
740 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
741 {
742 	struct dev_event_info *n1;
743 	int dis, error;
744 
745 	dis = devctl_queue_length == 0;
746 	error = sysctl_handle_int(oidp, &dis, 0, req);
747 	if (error || !req->newptr)
748 		return (error);
749 	mtx_lock(&devsoftc.mtx);
750 	if (dis) {
751 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
752 			n1 = TAILQ_FIRST(&devsoftc.devq);
753 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
754 			free(n1->dei_data, M_BUS);
755 			free(n1, M_BUS);
756 		}
757 		devsoftc.queued = 0;
758 		devctl_queue_length = 0;
759 	} else {
760 		devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
761 	}
762 	mtx_unlock(&devsoftc.mtx);
763 	return (0);
764 }
765 
766 static int
767 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
768 {
769 	struct dev_event_info *n1;
770 	int q, error;
771 
772 	q = devctl_queue_length;
773 	error = sysctl_handle_int(oidp, &q, 0, req);
774 	if (error || !req->newptr)
775 		return (error);
776 	if (q < 0)
777 		return (EINVAL);
778 	mtx_lock(&devsoftc.mtx);
779 	devctl_queue_length = q;
780 	while (devsoftc.queued > devctl_queue_length) {
781 		n1 = TAILQ_FIRST(&devsoftc.devq);
782 		TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
783 		free(n1->dei_data, M_BUS);
784 		free(n1, M_BUS);
785 		devsoftc.queued--;
786 	}
787 	mtx_unlock(&devsoftc.mtx);
788 	return (0);
789 }
790 
791 /* End of /dev/devctl code */
792 
793 static TAILQ_HEAD(,device)	bus_data_devices;
794 static int bus_data_generation = 1;
795 
796 static kobj_method_t null_methods[] = {
797 	KOBJMETHOD_END
798 };
799 
800 DEFINE_CLASS(null, null_methods, 0);
801 
802 /*
803  * Bus pass implementation
804  */
805 
806 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
807 int bus_current_pass = BUS_PASS_ROOT;
808 
809 /**
810  * @internal
811  * @brief Register the pass level of a new driver attachment
812  *
813  * Register a new driver attachment's pass level.  If no driver
814  * attachment with the same pass level has been added, then @p new
815  * will be added to the global passes list.
816  *
817  * @param new		the new driver attachment
818  */
819 static void
820 driver_register_pass(struct driverlink *new)
821 {
822 	struct driverlink *dl;
823 
824 	/* We only consider pass numbers during boot. */
825 	if (bus_current_pass == BUS_PASS_DEFAULT)
826 		return;
827 
828 	/*
829 	 * Walk the passes list.  If we already know about this pass
830 	 * then there is nothing to do.  If we don't, then insert this
831 	 * driver link into the list.
832 	 */
833 	TAILQ_FOREACH(dl, &passes, passlink) {
834 		if (dl->pass < new->pass)
835 			continue;
836 		if (dl->pass == new->pass)
837 			return;
838 		TAILQ_INSERT_BEFORE(dl, new, passlink);
839 		return;
840 	}
841 	TAILQ_INSERT_TAIL(&passes, new, passlink);
842 }
843 
844 /**
845  * @brief Raise the current bus pass
846  *
847  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
848  * method on the root bus to kick off a new device tree scan for each
849  * new pass level that has at least one driver.
850  */
851 void
852 bus_set_pass(int pass)
853 {
854 	struct driverlink *dl;
855 
856 	if (bus_current_pass > pass)
857 		panic("Attempt to lower bus pass level");
858 
859 	TAILQ_FOREACH(dl, &passes, passlink) {
860 		/* Skip pass values below the current pass level. */
861 		if (dl->pass <= bus_current_pass)
862 			continue;
863 
864 		/*
865 		 * Bail once we hit a driver with a pass level that is
866 		 * too high.
867 		 */
868 		if (dl->pass > pass)
869 			break;
870 
871 		/*
872 		 * Raise the pass level to the next level and rescan
873 		 * the tree.
874 		 */
875 		bus_current_pass = dl->pass;
876 		BUS_NEW_PASS(root_bus);
877 	}
878 
879 	/*
880 	 * If there isn't a driver registered for the requested pass,
881 	 * then bus_current_pass might still be less than 'pass'.  Set
882 	 * it to 'pass' in that case.
883 	 */
884 	if (bus_current_pass < pass)
885 		bus_current_pass = pass;
886 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
887 }
888 
889 /*
890  * Devclass implementation
891  */
892 
893 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
894 
895 /**
896  * @internal
897  * @brief Find or create a device class
898  *
899  * If a device class with the name @p classname exists, return it,
900  * otherwise if @p create is non-zero create and return a new device
901  * class.
902  *
903  * If @p parentname is non-NULL, the parent of the devclass is set to
904  * the devclass of that name.
905  *
906  * @param classname	the devclass name to find or create
907  * @param parentname	the parent devclass name or @c NULL
908  * @param create	non-zero to create a devclass
909  */
910 static devclass_t
911 devclass_find_internal(const char *classname, const char *parentname,
912 		       int create)
913 {
914 	devclass_t dc;
915 
916 	PDEBUG(("looking for %s", classname));
917 	if (!classname)
918 		return (NULL);
919 
920 	TAILQ_FOREACH(dc, &devclasses, link) {
921 		if (!strcmp(dc->name, classname))
922 			break;
923 	}
924 
925 	if (create && !dc) {
926 		PDEBUG(("creating %s", classname));
927 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
928 		    M_BUS, M_NOWAIT | M_ZERO);
929 		if (!dc)
930 			return (NULL);
931 		dc->parent = NULL;
932 		dc->name = (char*) (dc + 1);
933 		strcpy(dc->name, classname);
934 		TAILQ_INIT(&dc->drivers);
935 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
936 
937 		bus_data_generation_update();
938 	}
939 
940 	/*
941 	 * If a parent class is specified, then set that as our parent so
942 	 * that this devclass will support drivers for the parent class as
943 	 * well.  If the parent class has the same name don't do this though
944 	 * as it creates a cycle that can trigger an infinite loop in
945 	 * device_probe_child() if a device exists for which there is no
946 	 * suitable driver.
947 	 */
948 	if (parentname && dc && !dc->parent &&
949 	    strcmp(classname, parentname) != 0) {
950 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
951 		dc->parent->flags |= DC_HAS_CHILDREN;
952 	}
953 
954 	return (dc);
955 }
956 
957 /**
958  * @brief Create a device class
959  *
960  * If a device class with the name @p classname exists, return it,
961  * otherwise create and return a new device class.
962  *
963  * @param classname	the devclass name to find or create
964  */
965 devclass_t
966 devclass_create(const char *classname)
967 {
968 	return (devclass_find_internal(classname, NULL, TRUE));
969 }
970 
971 /**
972  * @brief Find a device class
973  *
974  * If a device class with the name @p classname exists, return it,
975  * otherwise return @c NULL.
976  *
977  * @param classname	the devclass name to find
978  */
979 devclass_t
980 devclass_find(const char *classname)
981 {
982 	return (devclass_find_internal(classname, NULL, FALSE));
983 }
984 
985 /**
986  * @brief Register that a device driver has been added to a devclass
987  *
988  * Register that a device driver has been added to a devclass.  This
989  * is called by devclass_add_driver to accomplish the recursive
990  * notification of all the children classes of dc, as well as dc.
991  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
992  * the devclass.
993  *
994  * We do a full search here of the devclass list at each iteration
995  * level to save storing children-lists in the devclass structure.  If
996  * we ever move beyond a few dozen devices doing this, we may need to
997  * reevaluate...
998  *
999  * @param dc		the devclass to edit
1000  * @param driver	the driver that was just added
1001  */
1002 static void
1003 devclass_driver_added(devclass_t dc, driver_t *driver)
1004 {
1005 	devclass_t parent;
1006 	int i;
1007 
1008 	/*
1009 	 * Call BUS_DRIVER_ADDED for any existing busses in this class.
1010 	 */
1011 	for (i = 0; i < dc->maxunit; i++)
1012 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1013 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1014 
1015 	/*
1016 	 * Walk through the children classes.  Since we only keep a
1017 	 * single parent pointer around, we walk the entire list of
1018 	 * devclasses looking for children.  We set the
1019 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1020 	 * the parent, so we only walk the list for those devclasses
1021 	 * that have children.
1022 	 */
1023 	if (!(dc->flags & DC_HAS_CHILDREN))
1024 		return;
1025 	parent = dc;
1026 	TAILQ_FOREACH(dc, &devclasses, link) {
1027 		if (dc->parent == parent)
1028 			devclass_driver_added(dc, driver);
1029 	}
1030 }
1031 
1032 /**
1033  * @brief Add a device driver to a device class
1034  *
1035  * Add a device driver to a devclass. This is normally called
1036  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1037  * all devices in the devclass will be called to allow them to attempt
1038  * to re-probe any unmatched children.
1039  *
1040  * @param dc		the devclass to edit
1041  * @param driver	the driver to register
1042  */
1043 int
1044 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1045 {
1046 	driverlink_t dl;
1047 	const char *parentname;
1048 
1049 	PDEBUG(("%s", DRIVERNAME(driver)));
1050 
1051 	/* Don't allow invalid pass values. */
1052 	if (pass <= BUS_PASS_ROOT)
1053 		return (EINVAL);
1054 
1055 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1056 	if (!dl)
1057 		return (ENOMEM);
1058 
1059 	/*
1060 	 * Compile the driver's methods. Also increase the reference count
1061 	 * so that the class doesn't get freed when the last instance
1062 	 * goes. This means we can safely use static methods and avoids a
1063 	 * double-free in devclass_delete_driver.
1064 	 */
1065 	kobj_class_compile((kobj_class_t) driver);
1066 
1067 	/*
1068 	 * If the driver has any base classes, make the
1069 	 * devclass inherit from the devclass of the driver's
1070 	 * first base class. This will allow the system to
1071 	 * search for drivers in both devclasses for children
1072 	 * of a device using this driver.
1073 	 */
1074 	if (driver->baseclasses)
1075 		parentname = driver->baseclasses[0]->name;
1076 	else
1077 		parentname = NULL;
1078 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1079 
1080 	dl->driver = driver;
1081 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1082 	driver->refs++;		/* XXX: kobj_mtx */
1083 	dl->pass = pass;
1084 	driver_register_pass(dl);
1085 
1086 	devclass_driver_added(dc, driver);
1087 	bus_data_generation_update();
1088 	return (0);
1089 }
1090 
1091 /**
1092  * @brief Register that a device driver has been deleted from a devclass
1093  *
1094  * Register that a device driver has been removed from a devclass.
1095  * This is called by devclass_delete_driver to accomplish the
1096  * recursive notification of all the children classes of busclass, as
1097  * well as busclass.  Each layer will attempt to detach the driver
1098  * from any devices that are children of the bus's devclass.  The function
1099  * will return an error if a device fails to detach.
1100  *
1101  * We do a full search here of the devclass list at each iteration
1102  * level to save storing children-lists in the devclass structure.  If
1103  * we ever move beyond a few dozen devices doing this, we may need to
1104  * reevaluate...
1105  *
1106  * @param busclass	the devclass of the parent bus
1107  * @param dc		the devclass of the driver being deleted
1108  * @param driver	the driver being deleted
1109  */
1110 static int
1111 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1112 {
1113 	devclass_t parent;
1114 	device_t dev;
1115 	int error, i;
1116 
1117 	/*
1118 	 * Disassociate from any devices.  We iterate through all the
1119 	 * devices in the devclass of the driver and detach any which are
1120 	 * using the driver and which have a parent in the devclass which
1121 	 * we are deleting from.
1122 	 *
1123 	 * Note that since a driver can be in multiple devclasses, we
1124 	 * should not detach devices which are not children of devices in
1125 	 * the affected devclass.
1126 	 */
1127 	for (i = 0; i < dc->maxunit; i++) {
1128 		if (dc->devices[i]) {
1129 			dev = dc->devices[i];
1130 			if (dev->driver == driver && dev->parent &&
1131 			    dev->parent->devclass == busclass) {
1132 				if ((error = device_detach(dev)) != 0)
1133 					return (error);
1134 				BUS_PROBE_NOMATCH(dev->parent, dev);
1135 				devnomatch(dev);
1136 				dev->flags |= DF_DONENOMATCH;
1137 			}
1138 		}
1139 	}
1140 
1141 	/*
1142 	 * Walk through the children classes.  Since we only keep a
1143 	 * single parent pointer around, we walk the entire list of
1144 	 * devclasses looking for children.  We set the
1145 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1146 	 * the parent, so we only walk the list for those devclasses
1147 	 * that have children.
1148 	 */
1149 	if (!(busclass->flags & DC_HAS_CHILDREN))
1150 		return (0);
1151 	parent = busclass;
1152 	TAILQ_FOREACH(busclass, &devclasses, link) {
1153 		if (busclass->parent == parent) {
1154 			error = devclass_driver_deleted(busclass, dc, driver);
1155 			if (error)
1156 				return (error);
1157 		}
1158 	}
1159 	return (0);
1160 }
1161 
1162 /**
1163  * @brief Delete a device driver from a device class
1164  *
1165  * Delete a device driver from a devclass. This is normally called
1166  * automatically by DRIVER_MODULE().
1167  *
1168  * If the driver is currently attached to any devices,
1169  * devclass_delete_driver() will first attempt to detach from each
1170  * device. If one of the detach calls fails, the driver will not be
1171  * deleted.
1172  *
1173  * @param dc		the devclass to edit
1174  * @param driver	the driver to unregister
1175  */
1176 int
1177 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1178 {
1179 	devclass_t dc = devclass_find(driver->name);
1180 	driverlink_t dl;
1181 	int error;
1182 
1183 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1184 
1185 	if (!dc)
1186 		return (0);
1187 
1188 	/*
1189 	 * Find the link structure in the bus' list of drivers.
1190 	 */
1191 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1192 		if (dl->driver == driver)
1193 			break;
1194 	}
1195 
1196 	if (!dl) {
1197 		PDEBUG(("%s not found in %s list", driver->name,
1198 		    busclass->name));
1199 		return (ENOENT);
1200 	}
1201 
1202 	error = devclass_driver_deleted(busclass, dc, driver);
1203 	if (error != 0)
1204 		return (error);
1205 
1206 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1207 	free(dl, M_BUS);
1208 
1209 	/* XXX: kobj_mtx */
1210 	driver->refs--;
1211 	if (driver->refs == 0)
1212 		kobj_class_free((kobj_class_t) driver);
1213 
1214 	bus_data_generation_update();
1215 	return (0);
1216 }
1217 
1218 /**
1219  * @brief Quiesces a set of device drivers from a device class
1220  *
1221  * Quiesce a device driver from a devclass. This is normally called
1222  * automatically by DRIVER_MODULE().
1223  *
1224  * If the driver is currently attached to any devices,
1225  * devclass_quiesece_driver() will first attempt to quiesce each
1226  * device.
1227  *
1228  * @param dc		the devclass to edit
1229  * @param driver	the driver to unregister
1230  */
1231 static int
1232 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1233 {
1234 	devclass_t dc = devclass_find(driver->name);
1235 	driverlink_t dl;
1236 	device_t dev;
1237 	int i;
1238 	int error;
1239 
1240 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1241 
1242 	if (!dc)
1243 		return (0);
1244 
1245 	/*
1246 	 * Find the link structure in the bus' list of drivers.
1247 	 */
1248 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1249 		if (dl->driver == driver)
1250 			break;
1251 	}
1252 
1253 	if (!dl) {
1254 		PDEBUG(("%s not found in %s list", driver->name,
1255 		    busclass->name));
1256 		return (ENOENT);
1257 	}
1258 
1259 	/*
1260 	 * Quiesce all devices.  We iterate through all the devices in
1261 	 * the devclass of the driver and quiesce any which are using
1262 	 * the driver and which have a parent in the devclass which we
1263 	 * are quiescing.
1264 	 *
1265 	 * Note that since a driver can be in multiple devclasses, we
1266 	 * should not quiesce devices which are not children of
1267 	 * devices in the affected devclass.
1268 	 */
1269 	for (i = 0; i < dc->maxunit; i++) {
1270 		if (dc->devices[i]) {
1271 			dev = dc->devices[i];
1272 			if (dev->driver == driver && dev->parent &&
1273 			    dev->parent->devclass == busclass) {
1274 				if ((error = device_quiesce(dev)) != 0)
1275 					return (error);
1276 			}
1277 		}
1278 	}
1279 
1280 	return (0);
1281 }
1282 
1283 /**
1284  * @internal
1285  */
1286 static driverlink_t
1287 devclass_find_driver_internal(devclass_t dc, const char *classname)
1288 {
1289 	driverlink_t dl;
1290 
1291 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1292 
1293 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1294 		if (!strcmp(dl->driver->name, classname))
1295 			return (dl);
1296 	}
1297 
1298 	PDEBUG(("not found"));
1299 	return (NULL);
1300 }
1301 
1302 /**
1303  * @brief Return the name of the devclass
1304  */
1305 const char *
1306 devclass_get_name(devclass_t dc)
1307 {
1308 	return (dc->name);
1309 }
1310 
1311 /**
1312  * @brief Find a device given a unit number
1313  *
1314  * @param dc		the devclass to search
1315  * @param unit		the unit number to search for
1316  *
1317  * @returns		the device with the given unit number or @c
1318  *			NULL if there is no such device
1319  */
1320 device_t
1321 devclass_get_device(devclass_t dc, int unit)
1322 {
1323 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1324 		return (NULL);
1325 	return (dc->devices[unit]);
1326 }
1327 
1328 /**
1329  * @brief Find the softc field of a device given a unit number
1330  *
1331  * @param dc		the devclass to search
1332  * @param unit		the unit number to search for
1333  *
1334  * @returns		the softc field of the device with the given
1335  *			unit number or @c NULL if there is no such
1336  *			device
1337  */
1338 void *
1339 devclass_get_softc(devclass_t dc, int unit)
1340 {
1341 	device_t dev;
1342 
1343 	dev = devclass_get_device(dc, unit);
1344 	if (!dev)
1345 		return (NULL);
1346 
1347 	return (device_get_softc(dev));
1348 }
1349 
1350 /**
1351  * @brief Get a list of devices in the devclass
1352  *
1353  * An array containing a list of all the devices in the given devclass
1354  * is allocated and returned in @p *devlistp. The number of devices
1355  * in the array is returned in @p *devcountp. The caller should free
1356  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1357  *
1358  * @param dc		the devclass to examine
1359  * @param devlistp	points at location for array pointer return
1360  *			value
1361  * @param devcountp	points at location for array size return value
1362  *
1363  * @retval 0		success
1364  * @retval ENOMEM	the array allocation failed
1365  */
1366 int
1367 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1368 {
1369 	int count, i;
1370 	device_t *list;
1371 
1372 	count = devclass_get_count(dc);
1373 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1374 	if (!list)
1375 		return (ENOMEM);
1376 
1377 	count = 0;
1378 	for (i = 0; i < dc->maxunit; i++) {
1379 		if (dc->devices[i]) {
1380 			list[count] = dc->devices[i];
1381 			count++;
1382 		}
1383 	}
1384 
1385 	*devlistp = list;
1386 	*devcountp = count;
1387 
1388 	return (0);
1389 }
1390 
1391 /**
1392  * @brief Get a list of drivers in the devclass
1393  *
1394  * An array containing a list of pointers to all the drivers in the
1395  * given devclass is allocated and returned in @p *listp.  The number
1396  * of drivers in the array is returned in @p *countp. The caller should
1397  * free the array using @c free(p, M_TEMP).
1398  *
1399  * @param dc		the devclass to examine
1400  * @param listp		gives location for array pointer return value
1401  * @param countp	gives location for number of array elements
1402  *			return value
1403  *
1404  * @retval 0		success
1405  * @retval ENOMEM	the array allocation failed
1406  */
1407 int
1408 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1409 {
1410 	driverlink_t dl;
1411 	driver_t **list;
1412 	int count;
1413 
1414 	count = 0;
1415 	TAILQ_FOREACH(dl, &dc->drivers, link)
1416 		count++;
1417 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1418 	if (list == NULL)
1419 		return (ENOMEM);
1420 
1421 	count = 0;
1422 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1423 		list[count] = dl->driver;
1424 		count++;
1425 	}
1426 	*listp = list;
1427 	*countp = count;
1428 
1429 	return (0);
1430 }
1431 
1432 /**
1433  * @brief Get the number of devices in a devclass
1434  *
1435  * @param dc		the devclass to examine
1436  */
1437 int
1438 devclass_get_count(devclass_t dc)
1439 {
1440 	int count, i;
1441 
1442 	count = 0;
1443 	for (i = 0; i < dc->maxunit; i++)
1444 		if (dc->devices[i])
1445 			count++;
1446 	return (count);
1447 }
1448 
1449 /**
1450  * @brief Get the maximum unit number used in a devclass
1451  *
1452  * Note that this is one greater than the highest currently-allocated
1453  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1454  * that not even the devclass has been allocated yet.
1455  *
1456  * @param dc		the devclass to examine
1457  */
1458 int
1459 devclass_get_maxunit(devclass_t dc)
1460 {
1461 	if (dc == NULL)
1462 		return (-1);
1463 	return (dc->maxunit);
1464 }
1465 
1466 /**
1467  * @brief Find a free unit number in a devclass
1468  *
1469  * This function searches for the first unused unit number greater
1470  * that or equal to @p unit.
1471  *
1472  * @param dc		the devclass to examine
1473  * @param unit		the first unit number to check
1474  */
1475 int
1476 devclass_find_free_unit(devclass_t dc, int unit)
1477 {
1478 	if (dc == NULL)
1479 		return (unit);
1480 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1481 		unit++;
1482 	return (unit);
1483 }
1484 
1485 /**
1486  * @brief Set the parent of a devclass
1487  *
1488  * The parent class is normally initialised automatically by
1489  * DRIVER_MODULE().
1490  *
1491  * @param dc		the devclass to edit
1492  * @param pdc		the new parent devclass
1493  */
1494 void
1495 devclass_set_parent(devclass_t dc, devclass_t pdc)
1496 {
1497 	dc->parent = pdc;
1498 }
1499 
1500 /**
1501  * @brief Get the parent of a devclass
1502  *
1503  * @param dc		the devclass to examine
1504  */
1505 devclass_t
1506 devclass_get_parent(devclass_t dc)
1507 {
1508 	return (dc->parent);
1509 }
1510 
1511 struct sysctl_ctx_list *
1512 devclass_get_sysctl_ctx(devclass_t dc)
1513 {
1514 	return (&dc->sysctl_ctx);
1515 }
1516 
1517 struct sysctl_oid *
1518 devclass_get_sysctl_tree(devclass_t dc)
1519 {
1520 	return (dc->sysctl_tree);
1521 }
1522 
1523 /**
1524  * @internal
1525  * @brief Allocate a unit number
1526  *
1527  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1528  * will do). The allocated unit number is returned in @p *unitp.
1529 
1530  * @param dc		the devclass to allocate from
1531  * @param unitp		points at the location for the allocated unit
1532  *			number
1533  *
1534  * @retval 0		success
1535  * @retval EEXIST	the requested unit number is already allocated
1536  * @retval ENOMEM	memory allocation failure
1537  */
1538 static int
1539 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1540 {
1541 	const char *s;
1542 	int unit = *unitp;
1543 
1544 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1545 
1546 	/* Ask the parent bus if it wants to wire this device. */
1547 	if (unit == -1)
1548 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1549 		    &unit);
1550 
1551 	/* If we were given a wired unit number, check for existing device */
1552 	/* XXX imp XXX */
1553 	if (unit != -1) {
1554 		if (unit >= 0 && unit < dc->maxunit &&
1555 		    dc->devices[unit] != NULL) {
1556 			if (bootverbose)
1557 				printf("%s: %s%d already exists; skipping it\n",
1558 				    dc->name, dc->name, *unitp);
1559 			return (EEXIST);
1560 		}
1561 	} else {
1562 		/* Unwired device, find the next available slot for it */
1563 		unit = 0;
1564 		for (unit = 0;; unit++) {
1565 			/* If there is an "at" hint for a unit then skip it. */
1566 			if (resource_string_value(dc->name, unit, "at", &s) ==
1567 			    0)
1568 				continue;
1569 
1570 			/* If this device slot is already in use, skip it. */
1571 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1572 				continue;
1573 
1574 			break;
1575 		}
1576 	}
1577 
1578 	/*
1579 	 * We've selected a unit beyond the length of the table, so let's
1580 	 * extend the table to make room for all units up to and including
1581 	 * this one.
1582 	 */
1583 	if (unit >= dc->maxunit) {
1584 		device_t *newlist, *oldlist;
1585 		int newsize;
1586 
1587 		oldlist = dc->devices;
1588 		newsize = roundup((unit + 1), MINALLOCSIZE / sizeof(device_t));
1589 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1590 		if (!newlist)
1591 			return (ENOMEM);
1592 		if (oldlist != NULL)
1593 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1594 		bzero(newlist + dc->maxunit,
1595 		    sizeof(device_t) * (newsize - dc->maxunit));
1596 		dc->devices = newlist;
1597 		dc->maxunit = newsize;
1598 		if (oldlist != NULL)
1599 			free(oldlist, M_BUS);
1600 	}
1601 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1602 
1603 	*unitp = unit;
1604 	return (0);
1605 }
1606 
1607 /**
1608  * @internal
1609  * @brief Add a device to a devclass
1610  *
1611  * A unit number is allocated for the device (using the device's
1612  * preferred unit number if any) and the device is registered in the
1613  * devclass. This allows the device to be looked up by its unit
1614  * number, e.g. by decoding a dev_t minor number.
1615  *
1616  * @param dc		the devclass to add to
1617  * @param dev		the device to add
1618  *
1619  * @retval 0		success
1620  * @retval EEXIST	the requested unit number is already allocated
1621  * @retval ENOMEM	memory allocation failure
1622  */
1623 static int
1624 devclass_add_device(devclass_t dc, device_t dev)
1625 {
1626 	int buflen, error;
1627 
1628 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1629 
1630 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1631 	if (buflen < 0)
1632 		return (ENOMEM);
1633 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1634 	if (!dev->nameunit)
1635 		return (ENOMEM);
1636 
1637 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1638 		free(dev->nameunit, M_BUS);
1639 		dev->nameunit = NULL;
1640 		return (error);
1641 	}
1642 	dc->devices[dev->unit] = dev;
1643 	dev->devclass = dc;
1644 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1645 
1646 	return (0);
1647 }
1648 
1649 /**
1650  * @internal
1651  * @brief Delete a device from a devclass
1652  *
1653  * The device is removed from the devclass's device list and its unit
1654  * number is freed.
1655 
1656  * @param dc		the devclass to delete from
1657  * @param dev		the device to delete
1658  *
1659  * @retval 0		success
1660  */
1661 static int
1662 devclass_delete_device(devclass_t dc, device_t dev)
1663 {
1664 	if (!dc || !dev)
1665 		return (0);
1666 
1667 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1668 
1669 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1670 		panic("devclass_delete_device: inconsistent device class");
1671 	dc->devices[dev->unit] = NULL;
1672 	if (dev->flags & DF_WILDCARD)
1673 		dev->unit = -1;
1674 	dev->devclass = NULL;
1675 	free(dev->nameunit, M_BUS);
1676 	dev->nameunit = NULL;
1677 
1678 	return (0);
1679 }
1680 
1681 /**
1682  * @internal
1683  * @brief Make a new device and add it as a child of @p parent
1684  *
1685  * @param parent	the parent of the new device
1686  * @param name		the devclass name of the new device or @c NULL
1687  *			to leave the devclass unspecified
1688  * @parem unit		the unit number of the new device of @c -1 to
1689  *			leave the unit number unspecified
1690  *
1691  * @returns the new device
1692  */
1693 static device_t
1694 make_device(device_t parent, const char *name, int unit)
1695 {
1696 	device_t dev;
1697 	devclass_t dc;
1698 
1699 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1700 
1701 	if (name) {
1702 		dc = devclass_find_internal(name, NULL, TRUE);
1703 		if (!dc) {
1704 			printf("make_device: can't find device class %s\n",
1705 			    name);
1706 			return (NULL);
1707 		}
1708 	} else {
1709 		dc = NULL;
1710 	}
1711 
1712 	dev = malloc(sizeof(struct device), M_BUS, M_NOWAIT|M_ZERO);
1713 	if (!dev)
1714 		return (NULL);
1715 
1716 	dev->parent = parent;
1717 	TAILQ_INIT(&dev->children);
1718 	kobj_init((kobj_t) dev, &null_class);
1719 	dev->driver = NULL;
1720 	dev->devclass = NULL;
1721 	dev->unit = unit;
1722 	dev->nameunit = NULL;
1723 	dev->desc = NULL;
1724 	dev->busy = 0;
1725 	dev->devflags = 0;
1726 	dev->flags = DF_ENABLED;
1727 	dev->order = 0;
1728 	if (unit == -1)
1729 		dev->flags |= DF_WILDCARD;
1730 	if (name) {
1731 		dev->flags |= DF_FIXEDCLASS;
1732 		if (devclass_add_device(dc, dev)) {
1733 			kobj_delete((kobj_t) dev, M_BUS);
1734 			return (NULL);
1735 		}
1736 	}
1737 	dev->ivars = NULL;
1738 	dev->softc = NULL;
1739 
1740 	dev->state = DS_NOTPRESENT;
1741 
1742 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1743 	bus_data_generation_update();
1744 
1745 	return (dev);
1746 }
1747 
1748 /**
1749  * @internal
1750  * @brief Print a description of a device.
1751  */
1752 static int
1753 device_print_child(device_t dev, device_t child)
1754 {
1755 	int retval = 0;
1756 
1757 	if (device_is_alive(child))
1758 		retval += BUS_PRINT_CHILD(dev, child);
1759 	else
1760 		retval += device_printf(child, " not found\n");
1761 
1762 	return (retval);
1763 }
1764 
1765 /**
1766  * @brief Create a new device
1767  *
1768  * This creates a new device and adds it as a child of an existing
1769  * parent device. The new device will be added after the last existing
1770  * child with order zero.
1771  *
1772  * @param dev		the device which will be the parent of the
1773  *			new child device
1774  * @param name		devclass name for new device or @c NULL if not
1775  *			specified
1776  * @param unit		unit number for new device or @c -1 if not
1777  *			specified
1778  *
1779  * @returns		the new device
1780  */
1781 device_t
1782 device_add_child(device_t dev, const char *name, int unit)
1783 {
1784 	return (device_add_child_ordered(dev, 0, name, unit));
1785 }
1786 
1787 /**
1788  * @brief Create a new device
1789  *
1790  * This creates a new device and adds it as a child of an existing
1791  * parent device. The new device will be added after the last existing
1792  * child with the same order.
1793  *
1794  * @param dev		the device which will be the parent of the
1795  *			new child device
1796  * @param order		a value which is used to partially sort the
1797  *			children of @p dev - devices created using
1798  *			lower values of @p order appear first in @p
1799  *			dev's list of children
1800  * @param name		devclass name for new device or @c NULL if not
1801  *			specified
1802  * @param unit		unit number for new device or @c -1 if not
1803  *			specified
1804  *
1805  * @returns		the new device
1806  */
1807 device_t
1808 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1809 {
1810 	device_t child;
1811 	device_t place;
1812 
1813 	PDEBUG(("%s at %s with order %u as unit %d",
1814 	    name, DEVICENAME(dev), order, unit));
1815 	KASSERT(name != NULL || unit == -1,
1816 	    ("child device with wildcard name and specific unit number"));
1817 
1818 	child = make_device(dev, name, unit);
1819 	if (child == NULL)
1820 		return (child);
1821 	child->order = order;
1822 
1823 	TAILQ_FOREACH(place, &dev->children, link) {
1824 		if (place->order > order)
1825 			break;
1826 	}
1827 
1828 	if (place) {
1829 		/*
1830 		 * The device 'place' is the first device whose order is
1831 		 * greater than the new child.
1832 		 */
1833 		TAILQ_INSERT_BEFORE(place, child, link);
1834 	} else {
1835 		/*
1836 		 * The new child's order is greater or equal to the order of
1837 		 * any existing device. Add the child to the tail of the list.
1838 		 */
1839 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1840 	}
1841 
1842 	bus_data_generation_update();
1843 	return (child);
1844 }
1845 
1846 /**
1847  * @brief Delete a device
1848  *
1849  * This function deletes a device along with all of its children. If
1850  * the device currently has a driver attached to it, the device is
1851  * detached first using device_detach().
1852  *
1853  * @param dev		the parent device
1854  * @param child		the device to delete
1855  *
1856  * @retval 0		success
1857  * @retval non-zero	a unit error code describing the error
1858  */
1859 int
1860 device_delete_child(device_t dev, device_t child)
1861 {
1862 	int error;
1863 	device_t grandchild;
1864 
1865 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1866 
1867 	/* remove children first */
1868 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1869 		error = device_delete_child(child, grandchild);
1870 		if (error)
1871 			return (error);
1872 	}
1873 
1874 	if ((error = device_detach(child)) != 0)
1875 		return (error);
1876 	if (child->devclass)
1877 		devclass_delete_device(child->devclass, child);
1878 	if (child->parent)
1879 		BUS_CHILD_DELETED(dev, child);
1880 	TAILQ_REMOVE(&dev->children, child, link);
1881 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1882 	kobj_delete((kobj_t) child, M_BUS);
1883 
1884 	bus_data_generation_update();
1885 	return (0);
1886 }
1887 
1888 /**
1889  * @brief Delete all children devices of the given device, if any.
1890  *
1891  * This function deletes all children devices of the given device, if
1892  * any, using the device_delete_child() function for each device it
1893  * finds. If a child device cannot be deleted, this function will
1894  * return an error code.
1895  *
1896  * @param dev		the parent device
1897  *
1898  * @retval 0		success
1899  * @retval non-zero	a device would not detach
1900  */
1901 int
1902 device_delete_children(device_t dev)
1903 {
1904 	device_t child;
1905 	int error;
1906 
1907 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
1908 
1909 	error = 0;
1910 
1911 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
1912 		error = device_delete_child(dev, child);
1913 		if (error) {
1914 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
1915 			break;
1916 		}
1917 	}
1918 	return (error);
1919 }
1920 
1921 /**
1922  * @brief Find a device given a unit number
1923  *
1924  * This is similar to devclass_get_devices() but only searches for
1925  * devices which have @p dev as a parent.
1926  *
1927  * @param dev		the parent device to search
1928  * @param unit		the unit number to search for.  If the unit is -1,
1929  *			return the first child of @p dev which has name
1930  *			@p classname (that is, the one with the lowest unit.)
1931  *
1932  * @returns		the device with the given unit number or @c
1933  *			NULL if there is no such device
1934  */
1935 device_t
1936 device_find_child(device_t dev, const char *classname, int unit)
1937 {
1938 	devclass_t dc;
1939 	device_t child;
1940 
1941 	dc = devclass_find(classname);
1942 	if (!dc)
1943 		return (NULL);
1944 
1945 	if (unit != -1) {
1946 		child = devclass_get_device(dc, unit);
1947 		if (child && child->parent == dev)
1948 			return (child);
1949 	} else {
1950 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
1951 			child = devclass_get_device(dc, unit);
1952 			if (child && child->parent == dev)
1953 				return (child);
1954 		}
1955 	}
1956 	return (NULL);
1957 }
1958 
1959 /**
1960  * @internal
1961  */
1962 static driverlink_t
1963 first_matching_driver(devclass_t dc, device_t dev)
1964 {
1965 	if (dev->devclass)
1966 		return (devclass_find_driver_internal(dc, dev->devclass->name));
1967 	return (TAILQ_FIRST(&dc->drivers));
1968 }
1969 
1970 /**
1971  * @internal
1972  */
1973 static driverlink_t
1974 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
1975 {
1976 	if (dev->devclass) {
1977 		driverlink_t dl;
1978 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
1979 			if (!strcmp(dev->devclass->name, dl->driver->name))
1980 				return (dl);
1981 		return (NULL);
1982 	}
1983 	return (TAILQ_NEXT(last, link));
1984 }
1985 
1986 /**
1987  * @internal
1988  */
1989 int
1990 device_probe_child(device_t dev, device_t child)
1991 {
1992 	devclass_t dc;
1993 	driverlink_t best = NULL;
1994 	driverlink_t dl;
1995 	int result, pri = 0;
1996 	int hasclass = (child->devclass != NULL);
1997 
1998 	GIANT_REQUIRED;
1999 
2000 	dc = dev->devclass;
2001 	if (!dc)
2002 		panic("device_probe_child: parent device has no devclass");
2003 
2004 	/*
2005 	 * If the state is already probed, then return.  However, don't
2006 	 * return if we can rebid this object.
2007 	 */
2008 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2009 		return (0);
2010 
2011 	for (; dc; dc = dc->parent) {
2012 		for (dl = first_matching_driver(dc, child);
2013 		     dl;
2014 		     dl = next_matching_driver(dc, child, dl)) {
2015 			/* If this driver's pass is too high, then ignore it. */
2016 			if (dl->pass > bus_current_pass)
2017 				continue;
2018 
2019 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2020 			result = device_set_driver(child, dl->driver);
2021 			if (result == ENOMEM)
2022 				return (result);
2023 			else if (result != 0)
2024 				continue;
2025 			if (!hasclass) {
2026 				if (device_set_devclass(child,
2027 				    dl->driver->name) != 0) {
2028 					char const * devname =
2029 					    device_get_name(child);
2030 					if (devname == NULL)
2031 						devname = "(unknown)";
2032 					printf("driver bug: Unable to set "
2033 					    "devclass (class: %s "
2034 					    "devname: %s)\n",
2035 					    dl->driver->name,
2036 					    devname);
2037 					(void)device_set_driver(child, NULL);
2038 					continue;
2039 				}
2040 			}
2041 
2042 			/* Fetch any flags for the device before probing. */
2043 			resource_int_value(dl->driver->name, child->unit,
2044 			    "flags", &child->devflags);
2045 
2046 			result = DEVICE_PROBE(child);
2047 
2048 			/* Reset flags and devclass before the next probe. */
2049 			child->devflags = 0;
2050 			if (!hasclass)
2051 				(void)device_set_devclass(child, NULL);
2052 
2053 			/*
2054 			 * If the driver returns SUCCESS, there can be
2055 			 * no higher match for this device.
2056 			 */
2057 			if (result == 0) {
2058 				best = dl;
2059 				pri = 0;
2060 				break;
2061 			}
2062 
2063 			/*
2064 			 * The driver returned an error so it
2065 			 * certainly doesn't match.
2066 			 */
2067 			if (result > 0) {
2068 				(void)device_set_driver(child, NULL);
2069 				continue;
2070 			}
2071 
2072 			/*
2073 			 * A priority lower than SUCCESS, remember the
2074 			 * best matching driver. Initialise the value
2075 			 * of pri for the first match.
2076 			 */
2077 			if (best == NULL || result > pri) {
2078 				/*
2079 				 * Probes that return BUS_PROBE_NOWILDCARD
2080 				 * or lower only match on devices whose
2081 				 * driver was explicitly specified.
2082 				 */
2083 				if (result <= BUS_PROBE_NOWILDCARD &&
2084 				    !(child->flags & DF_FIXEDCLASS))
2085 					continue;
2086 				best = dl;
2087 				pri = result;
2088 				continue;
2089 			}
2090 		}
2091 		/*
2092 		 * If we have an unambiguous match in this devclass,
2093 		 * don't look in the parent.
2094 		 */
2095 		if (best && pri == 0)
2096 			break;
2097 	}
2098 
2099 	/*
2100 	 * If we found a driver, change state and initialise the devclass.
2101 	 */
2102 	/* XXX What happens if we rebid and got no best? */
2103 	if (best) {
2104 		/*
2105 		 * If this device was attached, and we were asked to
2106 		 * rescan, and it is a different driver, then we have
2107 		 * to detach the old driver and reattach this new one.
2108 		 * Note, we don't have to check for DF_REBID here
2109 		 * because if the state is > DS_ALIVE, we know it must
2110 		 * be.
2111 		 *
2112 		 * This assumes that all DF_REBID drivers can have
2113 		 * their probe routine called at any time and that
2114 		 * they are idempotent as well as completely benign in
2115 		 * normal operations.
2116 		 *
2117 		 * We also have to make sure that the detach
2118 		 * succeeded, otherwise we fail the operation (or
2119 		 * maybe it should just fail silently?  I'm torn).
2120 		 */
2121 		if (child->state > DS_ALIVE && best->driver != child->driver)
2122 			if ((result = device_detach(dev)) != 0)
2123 				return (result);
2124 
2125 		/* Set the winning driver, devclass, and flags. */
2126 		if (!child->devclass) {
2127 			result = device_set_devclass(child, best->driver->name);
2128 			if (result != 0)
2129 				return (result);
2130 		}
2131 		result = device_set_driver(child, best->driver);
2132 		if (result != 0)
2133 			return (result);
2134 		resource_int_value(best->driver->name, child->unit,
2135 		    "flags", &child->devflags);
2136 
2137 		if (pri < 0) {
2138 			/*
2139 			 * A bit bogus. Call the probe method again to make
2140 			 * sure that we have the right description.
2141 			 */
2142 			DEVICE_PROBE(child);
2143 #if 0
2144 			child->flags |= DF_REBID;
2145 #endif
2146 		} else
2147 			child->flags &= ~DF_REBID;
2148 		child->state = DS_ALIVE;
2149 
2150 		bus_data_generation_update();
2151 		return (0);
2152 	}
2153 
2154 	return (ENXIO);
2155 }
2156 
2157 /**
2158  * @brief Return the parent of a device
2159  */
2160 device_t
2161 device_get_parent(device_t dev)
2162 {
2163 	return (dev->parent);
2164 }
2165 
2166 /**
2167  * @brief Get a list of children of a device
2168  *
2169  * An array containing a list of all the children of the given device
2170  * is allocated and returned in @p *devlistp. The number of devices
2171  * in the array is returned in @p *devcountp. The caller should free
2172  * the array using @c free(p, M_TEMP).
2173  *
2174  * @param dev		the device to examine
2175  * @param devlistp	points at location for array pointer return
2176  *			value
2177  * @param devcountp	points at location for array size return value
2178  *
2179  * @retval 0		success
2180  * @retval ENOMEM	the array allocation failed
2181  */
2182 int
2183 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2184 {
2185 	int count;
2186 	device_t child;
2187 	device_t *list;
2188 
2189 	count = 0;
2190 	TAILQ_FOREACH(child, &dev->children, link) {
2191 		count++;
2192 	}
2193 	if (count == 0) {
2194 		*devlistp = NULL;
2195 		*devcountp = 0;
2196 		return (0);
2197 	}
2198 
2199 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2200 	if (!list)
2201 		return (ENOMEM);
2202 
2203 	count = 0;
2204 	TAILQ_FOREACH(child, &dev->children, link) {
2205 		list[count] = child;
2206 		count++;
2207 	}
2208 
2209 	*devlistp = list;
2210 	*devcountp = count;
2211 
2212 	return (0);
2213 }
2214 
2215 /**
2216  * @brief Return the current driver for the device or @c NULL if there
2217  * is no driver currently attached
2218  */
2219 driver_t *
2220 device_get_driver(device_t dev)
2221 {
2222 	return (dev->driver);
2223 }
2224 
2225 /**
2226  * @brief Return the current devclass for the device or @c NULL if
2227  * there is none.
2228  */
2229 devclass_t
2230 device_get_devclass(device_t dev)
2231 {
2232 	return (dev->devclass);
2233 }
2234 
2235 /**
2236  * @brief Return the name of the device's devclass or @c NULL if there
2237  * is none.
2238  */
2239 const char *
2240 device_get_name(device_t dev)
2241 {
2242 	if (dev != NULL && dev->devclass)
2243 		return (devclass_get_name(dev->devclass));
2244 	return (NULL);
2245 }
2246 
2247 /**
2248  * @brief Return a string containing the device's devclass name
2249  * followed by an ascii representation of the device's unit number
2250  * (e.g. @c "foo2").
2251  */
2252 const char *
2253 device_get_nameunit(device_t dev)
2254 {
2255 	return (dev->nameunit);
2256 }
2257 
2258 /**
2259  * @brief Return the device's unit number.
2260  */
2261 int
2262 device_get_unit(device_t dev)
2263 {
2264 	return (dev->unit);
2265 }
2266 
2267 /**
2268  * @brief Return the device's description string
2269  */
2270 const char *
2271 device_get_desc(device_t dev)
2272 {
2273 	return (dev->desc);
2274 }
2275 
2276 /**
2277  * @brief Return the device's flags
2278  */
2279 uint32_t
2280 device_get_flags(device_t dev)
2281 {
2282 	return (dev->devflags);
2283 }
2284 
2285 struct sysctl_ctx_list *
2286 device_get_sysctl_ctx(device_t dev)
2287 {
2288 	return (&dev->sysctl_ctx);
2289 }
2290 
2291 struct sysctl_oid *
2292 device_get_sysctl_tree(device_t dev)
2293 {
2294 	return (dev->sysctl_tree);
2295 }
2296 
2297 /**
2298  * @brief Print the name of the device followed by a colon and a space
2299  *
2300  * @returns the number of characters printed
2301  */
2302 int
2303 device_print_prettyname(device_t dev)
2304 {
2305 	const char *name = device_get_name(dev);
2306 
2307 	if (name == NULL)
2308 		return (printf("unknown: "));
2309 	return (printf("%s%d: ", name, device_get_unit(dev)));
2310 }
2311 
2312 /**
2313  * @brief Print the name of the device followed by a colon, a space
2314  * and the result of calling vprintf() with the value of @p fmt and
2315  * the following arguments.
2316  *
2317  * @returns the number of characters printed
2318  */
2319 int
2320 device_printf(device_t dev, const char * fmt, ...)
2321 {
2322 	va_list ap;
2323 	int retval;
2324 
2325 	retval = device_print_prettyname(dev);
2326 	va_start(ap, fmt);
2327 	retval += vprintf(fmt, ap);
2328 	va_end(ap);
2329 	return (retval);
2330 }
2331 
2332 /**
2333  * @internal
2334  */
2335 static void
2336 device_set_desc_internal(device_t dev, const char* desc, int copy)
2337 {
2338 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2339 		free(dev->desc, M_BUS);
2340 		dev->flags &= ~DF_DESCMALLOCED;
2341 		dev->desc = NULL;
2342 	}
2343 
2344 	if (copy && desc) {
2345 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2346 		if (dev->desc) {
2347 			strcpy(dev->desc, desc);
2348 			dev->flags |= DF_DESCMALLOCED;
2349 		}
2350 	} else {
2351 		/* Avoid a -Wcast-qual warning */
2352 		dev->desc = (char *)(uintptr_t) desc;
2353 	}
2354 
2355 	bus_data_generation_update();
2356 }
2357 
2358 /**
2359  * @brief Set the device's description
2360  *
2361  * The value of @c desc should be a string constant that will not
2362  * change (at least until the description is changed in a subsequent
2363  * call to device_set_desc() or device_set_desc_copy()).
2364  */
2365 void
2366 device_set_desc(device_t dev, const char* desc)
2367 {
2368 	device_set_desc_internal(dev, desc, FALSE);
2369 }
2370 
2371 /**
2372  * @brief Set the device's description
2373  *
2374  * The string pointed to by @c desc is copied. Use this function if
2375  * the device description is generated, (e.g. with sprintf()).
2376  */
2377 void
2378 device_set_desc_copy(device_t dev, const char* desc)
2379 {
2380 	device_set_desc_internal(dev, desc, TRUE);
2381 }
2382 
2383 /**
2384  * @brief Set the device's flags
2385  */
2386 void
2387 device_set_flags(device_t dev, uint32_t flags)
2388 {
2389 	dev->devflags = flags;
2390 }
2391 
2392 /**
2393  * @brief Return the device's softc field
2394  *
2395  * The softc is allocated and zeroed when a driver is attached, based
2396  * on the size field of the driver.
2397  */
2398 void *
2399 device_get_softc(device_t dev)
2400 {
2401 	return (dev->softc);
2402 }
2403 
2404 /**
2405  * @brief Set the device's softc field
2406  *
2407  * Most drivers do not need to use this since the softc is allocated
2408  * automatically when the driver is attached.
2409  */
2410 void
2411 device_set_softc(device_t dev, void *softc)
2412 {
2413 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2414 		free(dev->softc, M_BUS_SC);
2415 	dev->softc = softc;
2416 	if (dev->softc)
2417 		dev->flags |= DF_EXTERNALSOFTC;
2418 	else
2419 		dev->flags &= ~DF_EXTERNALSOFTC;
2420 }
2421 
2422 /**
2423  * @brief Free claimed softc
2424  *
2425  * Most drivers do not need to use this since the softc is freed
2426  * automatically when the driver is detached.
2427  */
2428 void
2429 device_free_softc(void *softc)
2430 {
2431 	free(softc, M_BUS_SC);
2432 }
2433 
2434 /**
2435  * @brief Claim softc
2436  *
2437  * This function can be used to let the driver free the automatically
2438  * allocated softc using "device_free_softc()". This function is
2439  * useful when the driver is refcounting the softc and the softc
2440  * cannot be freed when the "device_detach" method is called.
2441  */
2442 void
2443 device_claim_softc(device_t dev)
2444 {
2445 	if (dev->softc)
2446 		dev->flags |= DF_EXTERNALSOFTC;
2447 	else
2448 		dev->flags &= ~DF_EXTERNALSOFTC;
2449 }
2450 
2451 /**
2452  * @brief Get the device's ivars field
2453  *
2454  * The ivars field is used by the parent device to store per-device
2455  * state (e.g. the physical location of the device or a list of
2456  * resources).
2457  */
2458 void *
2459 device_get_ivars(device_t dev)
2460 {
2461 
2462 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2463 	return (dev->ivars);
2464 }
2465 
2466 /**
2467  * @brief Set the device's ivars field
2468  */
2469 void
2470 device_set_ivars(device_t dev, void * ivars)
2471 {
2472 
2473 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2474 	dev->ivars = ivars;
2475 }
2476 
2477 /**
2478  * @brief Return the device's state
2479  */
2480 device_state_t
2481 device_get_state(device_t dev)
2482 {
2483 	return (dev->state);
2484 }
2485 
2486 /**
2487  * @brief Set the DF_ENABLED flag for the device
2488  */
2489 void
2490 device_enable(device_t dev)
2491 {
2492 	dev->flags |= DF_ENABLED;
2493 }
2494 
2495 /**
2496  * @brief Clear the DF_ENABLED flag for the device
2497  */
2498 void
2499 device_disable(device_t dev)
2500 {
2501 	dev->flags &= ~DF_ENABLED;
2502 }
2503 
2504 /**
2505  * @brief Increment the busy counter for the device
2506  */
2507 void
2508 device_busy(device_t dev)
2509 {
2510 	if (dev->state < DS_ATTACHING)
2511 		panic("device_busy: called for unattached device");
2512 	if (dev->busy == 0 && dev->parent)
2513 		device_busy(dev->parent);
2514 	dev->busy++;
2515 	if (dev->state == DS_ATTACHED)
2516 		dev->state = DS_BUSY;
2517 }
2518 
2519 /**
2520  * @brief Decrement the busy counter for the device
2521  */
2522 void
2523 device_unbusy(device_t dev)
2524 {
2525 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2526 	    dev->state != DS_ATTACHING)
2527 		panic("device_unbusy: called for non-busy device %s",
2528 		    device_get_nameunit(dev));
2529 	dev->busy--;
2530 	if (dev->busy == 0) {
2531 		if (dev->parent)
2532 			device_unbusy(dev->parent);
2533 		if (dev->state == DS_BUSY)
2534 			dev->state = DS_ATTACHED;
2535 	}
2536 }
2537 
2538 /**
2539  * @brief Set the DF_QUIET flag for the device
2540  */
2541 void
2542 device_quiet(device_t dev)
2543 {
2544 	dev->flags |= DF_QUIET;
2545 }
2546 
2547 /**
2548  * @brief Clear the DF_QUIET flag for the device
2549  */
2550 void
2551 device_verbose(device_t dev)
2552 {
2553 	dev->flags &= ~DF_QUIET;
2554 }
2555 
2556 /**
2557  * @brief Return non-zero if the DF_QUIET flag is set on the device
2558  */
2559 int
2560 device_is_quiet(device_t dev)
2561 {
2562 	return ((dev->flags & DF_QUIET) != 0);
2563 }
2564 
2565 /**
2566  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2567  */
2568 int
2569 device_is_enabled(device_t dev)
2570 {
2571 	return ((dev->flags & DF_ENABLED) != 0);
2572 }
2573 
2574 /**
2575  * @brief Return non-zero if the device was successfully probed
2576  */
2577 int
2578 device_is_alive(device_t dev)
2579 {
2580 	return (dev->state >= DS_ALIVE);
2581 }
2582 
2583 /**
2584  * @brief Return non-zero if the device currently has a driver
2585  * attached to it
2586  */
2587 int
2588 device_is_attached(device_t dev)
2589 {
2590 	return (dev->state >= DS_ATTACHED);
2591 }
2592 
2593 /**
2594  * @brief Set the devclass of a device
2595  * @see devclass_add_device().
2596  */
2597 int
2598 device_set_devclass(device_t dev, const char *classname)
2599 {
2600 	devclass_t dc;
2601 	int error;
2602 
2603 	if (!classname) {
2604 		if (dev->devclass)
2605 			devclass_delete_device(dev->devclass, dev);
2606 		return (0);
2607 	}
2608 
2609 	if (dev->devclass) {
2610 		printf("device_set_devclass: device class already set\n");
2611 		return (EINVAL);
2612 	}
2613 
2614 	dc = devclass_find_internal(classname, NULL, TRUE);
2615 	if (!dc)
2616 		return (ENOMEM);
2617 
2618 	error = devclass_add_device(dc, dev);
2619 
2620 	bus_data_generation_update();
2621 	return (error);
2622 }
2623 
2624 /**
2625  * @brief Set the driver of a device
2626  *
2627  * @retval 0		success
2628  * @retval EBUSY	the device already has a driver attached
2629  * @retval ENOMEM	a memory allocation failure occurred
2630  */
2631 int
2632 device_set_driver(device_t dev, driver_t *driver)
2633 {
2634 	if (dev->state >= DS_ATTACHED)
2635 		return (EBUSY);
2636 
2637 	if (dev->driver == driver)
2638 		return (0);
2639 
2640 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2641 		free(dev->softc, M_BUS_SC);
2642 		dev->softc = NULL;
2643 	}
2644 	device_set_desc(dev, NULL);
2645 	kobj_delete((kobj_t) dev, NULL);
2646 	dev->driver = driver;
2647 	if (driver) {
2648 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2649 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2650 			dev->softc = malloc(driver->size, M_BUS_SC,
2651 			    M_NOWAIT | M_ZERO);
2652 			if (!dev->softc) {
2653 				kobj_delete((kobj_t) dev, NULL);
2654 				kobj_init((kobj_t) dev, &null_class);
2655 				dev->driver = NULL;
2656 				return (ENOMEM);
2657 			}
2658 		}
2659 	} else {
2660 		kobj_init((kobj_t) dev, &null_class);
2661 	}
2662 
2663 	bus_data_generation_update();
2664 	return (0);
2665 }
2666 
2667 /**
2668  * @brief Probe a device, and return this status.
2669  *
2670  * This function is the core of the device autoconfiguration
2671  * system. Its purpose is to select a suitable driver for a device and
2672  * then call that driver to initialise the hardware appropriately. The
2673  * driver is selected by calling the DEVICE_PROBE() method of a set of
2674  * candidate drivers and then choosing the driver which returned the
2675  * best value. This driver is then attached to the device using
2676  * device_attach().
2677  *
2678  * The set of suitable drivers is taken from the list of drivers in
2679  * the parent device's devclass. If the device was originally created
2680  * with a specific class name (see device_add_child()), only drivers
2681  * with that name are probed, otherwise all drivers in the devclass
2682  * are probed. If no drivers return successful probe values in the
2683  * parent devclass, the search continues in the parent of that
2684  * devclass (see devclass_get_parent()) if any.
2685  *
2686  * @param dev		the device to initialise
2687  *
2688  * @retval 0		success
2689  * @retval ENXIO	no driver was found
2690  * @retval ENOMEM	memory allocation failure
2691  * @retval non-zero	some other unix error code
2692  * @retval -1		Device already attached
2693  */
2694 int
2695 device_probe(device_t dev)
2696 {
2697 	int error;
2698 
2699 	GIANT_REQUIRED;
2700 
2701 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2702 		return (-1);
2703 
2704 	if (!(dev->flags & DF_ENABLED)) {
2705 		if (bootverbose && device_get_name(dev) != NULL) {
2706 			device_print_prettyname(dev);
2707 			printf("not probed (disabled)\n");
2708 		}
2709 		return (-1);
2710 	}
2711 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2712 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2713 		    !(dev->flags & DF_DONENOMATCH)) {
2714 			BUS_PROBE_NOMATCH(dev->parent, dev);
2715 			devnomatch(dev);
2716 			dev->flags |= DF_DONENOMATCH;
2717 		}
2718 		return (error);
2719 	}
2720 	return (0);
2721 }
2722 
2723 /**
2724  * @brief Probe a device and attach a driver if possible
2725  *
2726  * calls device_probe() and attaches if that was successful.
2727  */
2728 int
2729 device_probe_and_attach(device_t dev)
2730 {
2731 	int error;
2732 
2733 	GIANT_REQUIRED;
2734 
2735 	error = device_probe(dev);
2736 	if (error == -1)
2737 		return (0);
2738 	else if (error != 0)
2739 		return (error);
2740 
2741 	CURVNET_SET_QUIET(vnet0);
2742 	error = device_attach(dev);
2743 	CURVNET_RESTORE();
2744 	return error;
2745 }
2746 
2747 /**
2748  * @brief Attach a device driver to a device
2749  *
2750  * This function is a wrapper around the DEVICE_ATTACH() driver
2751  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2752  * device's sysctl tree, optionally prints a description of the device
2753  * and queues a notification event for user-based device management
2754  * services.
2755  *
2756  * Normally this function is only called internally from
2757  * device_probe_and_attach().
2758  *
2759  * @param dev		the device to initialise
2760  *
2761  * @retval 0		success
2762  * @retval ENXIO	no driver was found
2763  * @retval ENOMEM	memory allocation failure
2764  * @retval non-zero	some other unix error code
2765  */
2766 int
2767 device_attach(device_t dev)
2768 {
2769 	int error;
2770 
2771 	if (resource_disabled(dev->driver->name, dev->unit)) {
2772 		device_disable(dev);
2773 		if (bootverbose)
2774 			 device_printf(dev, "disabled via hints entry\n");
2775 		return (ENXIO);
2776 	}
2777 
2778 	device_sysctl_init(dev);
2779 	if (!device_is_quiet(dev))
2780 		device_print_child(dev->parent, dev);
2781 	dev->state = DS_ATTACHING;
2782 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2783 		printf("device_attach: %s%d attach returned %d\n",
2784 		    dev->driver->name, dev->unit, error);
2785 		if (!(dev->flags & DF_FIXEDCLASS))
2786 			devclass_delete_device(dev->devclass, dev);
2787 		(void)device_set_driver(dev, NULL);
2788 		device_sysctl_fini(dev);
2789 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2790 		dev->state = DS_NOTPRESENT;
2791 		return (error);
2792 	}
2793 	device_sysctl_update(dev);
2794 	if (dev->busy)
2795 		dev->state = DS_BUSY;
2796 	else
2797 		dev->state = DS_ATTACHED;
2798 	dev->flags &= ~DF_DONENOMATCH;
2799 	devadded(dev);
2800 	return (0);
2801 }
2802 
2803 /**
2804  * @brief Detach a driver from a device
2805  *
2806  * This function is a wrapper around the DEVICE_DETACH() driver
2807  * method. If the call to DEVICE_DETACH() succeeds, it calls
2808  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
2809  * notification event for user-based device management services and
2810  * cleans up the device's sysctl tree.
2811  *
2812  * @param dev		the device to un-initialise
2813  *
2814  * @retval 0		success
2815  * @retval ENXIO	no driver was found
2816  * @retval ENOMEM	memory allocation failure
2817  * @retval non-zero	some other unix error code
2818  */
2819 int
2820 device_detach(device_t dev)
2821 {
2822 	int error;
2823 
2824 	GIANT_REQUIRED;
2825 
2826 	PDEBUG(("%s", DEVICENAME(dev)));
2827 	if (dev->state == DS_BUSY)
2828 		return (EBUSY);
2829 	if (dev->state != DS_ATTACHED)
2830 		return (0);
2831 
2832 	if ((error = DEVICE_DETACH(dev)) != 0)
2833 		return (error);
2834 	devremoved(dev);
2835 	if (!device_is_quiet(dev))
2836 		device_printf(dev, "detached\n");
2837 	if (dev->parent)
2838 		BUS_CHILD_DETACHED(dev->parent, dev);
2839 
2840 	if (!(dev->flags & DF_FIXEDCLASS))
2841 		devclass_delete_device(dev->devclass, dev);
2842 
2843 	dev->state = DS_NOTPRESENT;
2844 	(void)device_set_driver(dev, NULL);
2845 	device_sysctl_fini(dev);
2846 
2847 	return (0);
2848 }
2849 
2850 /**
2851  * @brief Tells a driver to quiesce itself.
2852  *
2853  * This function is a wrapper around the DEVICE_QUIESCE() driver
2854  * method. If the call to DEVICE_QUIESCE() succeeds.
2855  *
2856  * @param dev		the device to quiesce
2857  *
2858  * @retval 0		success
2859  * @retval ENXIO	no driver was found
2860  * @retval ENOMEM	memory allocation failure
2861  * @retval non-zero	some other unix error code
2862  */
2863 int
2864 device_quiesce(device_t dev)
2865 {
2866 
2867 	PDEBUG(("%s", DEVICENAME(dev)));
2868 	if (dev->state == DS_BUSY)
2869 		return (EBUSY);
2870 	if (dev->state != DS_ATTACHED)
2871 		return (0);
2872 
2873 	return (DEVICE_QUIESCE(dev));
2874 }
2875 
2876 /**
2877  * @brief Notify a device of system shutdown
2878  *
2879  * This function calls the DEVICE_SHUTDOWN() driver method if the
2880  * device currently has an attached driver.
2881  *
2882  * @returns the value returned by DEVICE_SHUTDOWN()
2883  */
2884 int
2885 device_shutdown(device_t dev)
2886 {
2887 	if (dev->state < DS_ATTACHED)
2888 		return (0);
2889 	return (DEVICE_SHUTDOWN(dev));
2890 }
2891 
2892 /**
2893  * @brief Set the unit number of a device
2894  *
2895  * This function can be used to override the unit number used for a
2896  * device (e.g. to wire a device to a pre-configured unit number).
2897  */
2898 int
2899 device_set_unit(device_t dev, int unit)
2900 {
2901 	devclass_t dc;
2902 	int err;
2903 
2904 	dc = device_get_devclass(dev);
2905 	if (unit < dc->maxunit && dc->devices[unit])
2906 		return (EBUSY);
2907 	err = devclass_delete_device(dc, dev);
2908 	if (err)
2909 		return (err);
2910 	dev->unit = unit;
2911 	err = devclass_add_device(dc, dev);
2912 	if (err)
2913 		return (err);
2914 
2915 	bus_data_generation_update();
2916 	return (0);
2917 }
2918 
2919 /*======================================*/
2920 /*
2921  * Some useful method implementations to make life easier for bus drivers.
2922  */
2923 
2924 /**
2925  * @brief Initialise a resource list.
2926  *
2927  * @param rl		the resource list to initialise
2928  */
2929 void
2930 resource_list_init(struct resource_list *rl)
2931 {
2932 	STAILQ_INIT(rl);
2933 }
2934 
2935 /**
2936  * @brief Reclaim memory used by a resource list.
2937  *
2938  * This function frees the memory for all resource entries on the list
2939  * (if any).
2940  *
2941  * @param rl		the resource list to free
2942  */
2943 void
2944 resource_list_free(struct resource_list *rl)
2945 {
2946 	struct resource_list_entry *rle;
2947 
2948 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
2949 		if (rle->res)
2950 			panic("resource_list_free: resource entry is busy");
2951 		STAILQ_REMOVE_HEAD(rl, link);
2952 		free(rle, M_BUS);
2953 	}
2954 }
2955 
2956 /**
2957  * @brief Add a resource entry.
2958  *
2959  * This function adds a resource entry using the given @p type, @p
2960  * start, @p end and @p count values. A rid value is chosen by
2961  * searching sequentially for the first unused rid starting at zero.
2962  *
2963  * @param rl		the resource list to edit
2964  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2965  * @param start		the start address of the resource
2966  * @param end		the end address of the resource
2967  * @param count		XXX end-start+1
2968  */
2969 int
2970 resource_list_add_next(struct resource_list *rl, int type, u_long start,
2971     u_long end, u_long count)
2972 {
2973 	int rid;
2974 
2975 	rid = 0;
2976 	while (resource_list_find(rl, type, rid) != NULL)
2977 		rid++;
2978 	resource_list_add(rl, type, rid, start, end, count);
2979 	return (rid);
2980 }
2981 
2982 /**
2983  * @brief Add or modify a resource entry.
2984  *
2985  * If an existing entry exists with the same type and rid, it will be
2986  * modified using the given values of @p start, @p end and @p
2987  * count. If no entry exists, a new one will be created using the
2988  * given values.  The resource list entry that matches is then returned.
2989  *
2990  * @param rl		the resource list to edit
2991  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
2992  * @param rid		the resource identifier
2993  * @param start		the start address of the resource
2994  * @param end		the end address of the resource
2995  * @param count		XXX end-start+1
2996  */
2997 struct resource_list_entry *
2998 resource_list_add(struct resource_list *rl, int type, int rid,
2999     u_long start, u_long end, u_long count)
3000 {
3001 	struct resource_list_entry *rle;
3002 
3003 	rle = resource_list_find(rl, type, rid);
3004 	if (!rle) {
3005 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3006 		    M_NOWAIT);
3007 		if (!rle)
3008 			panic("resource_list_add: can't record entry");
3009 		STAILQ_INSERT_TAIL(rl, rle, link);
3010 		rle->type = type;
3011 		rle->rid = rid;
3012 		rle->res = NULL;
3013 		rle->flags = 0;
3014 	}
3015 
3016 	if (rle->res)
3017 		panic("resource_list_add: resource entry is busy");
3018 
3019 	rle->start = start;
3020 	rle->end = end;
3021 	rle->count = count;
3022 	return (rle);
3023 }
3024 
3025 /**
3026  * @brief Determine if a resource entry is busy.
3027  *
3028  * Returns true if a resource entry is busy meaning that it has an
3029  * associated resource that is not an unallocated "reserved" resource.
3030  *
3031  * @param rl		the resource list to search
3032  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3033  * @param rid		the resource identifier
3034  *
3035  * @returns Non-zero if the entry is busy, zero otherwise.
3036  */
3037 int
3038 resource_list_busy(struct resource_list *rl, int type, int rid)
3039 {
3040 	struct resource_list_entry *rle;
3041 
3042 	rle = resource_list_find(rl, type, rid);
3043 	if (rle == NULL || rle->res == NULL)
3044 		return (0);
3045 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3046 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3047 		    ("reserved resource is active"));
3048 		return (0);
3049 	}
3050 	return (1);
3051 }
3052 
3053 /**
3054  * @brief Determine if a resource entry is reserved.
3055  *
3056  * Returns true if a resource entry is reserved meaning that it has an
3057  * associated "reserved" resource.  The resource can either be
3058  * allocated or unallocated.
3059  *
3060  * @param rl		the resource list to search
3061  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3062  * @param rid		the resource identifier
3063  *
3064  * @returns Non-zero if the entry is reserved, zero otherwise.
3065  */
3066 int
3067 resource_list_reserved(struct resource_list *rl, int type, int rid)
3068 {
3069 	struct resource_list_entry *rle;
3070 
3071 	rle = resource_list_find(rl, type, rid);
3072 	if (rle != NULL && rle->flags & RLE_RESERVED)
3073 		return (1);
3074 	return (0);
3075 }
3076 
3077 /**
3078  * @brief Find a resource entry by type and rid.
3079  *
3080  * @param rl		the resource list to search
3081  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3082  * @param rid		the resource identifier
3083  *
3084  * @returns the resource entry pointer or NULL if there is no such
3085  * entry.
3086  */
3087 struct resource_list_entry *
3088 resource_list_find(struct resource_list *rl, int type, int rid)
3089 {
3090 	struct resource_list_entry *rle;
3091 
3092 	STAILQ_FOREACH(rle, rl, link) {
3093 		if (rle->type == type && rle->rid == rid)
3094 			return (rle);
3095 	}
3096 	return (NULL);
3097 }
3098 
3099 /**
3100  * @brief Delete a resource entry.
3101  *
3102  * @param rl		the resource list to edit
3103  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3104  * @param rid		the resource identifier
3105  */
3106 void
3107 resource_list_delete(struct resource_list *rl, int type, int rid)
3108 {
3109 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3110 
3111 	if (rle) {
3112 		if (rle->res != NULL)
3113 			panic("resource_list_delete: resource has not been released");
3114 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3115 		free(rle, M_BUS);
3116 	}
3117 }
3118 
3119 /**
3120  * @brief Allocate a reserved resource
3121  *
3122  * This can be used by busses to force the allocation of resources
3123  * that are always active in the system even if they are not allocated
3124  * by a driver (e.g. PCI BARs).  This function is usually called when
3125  * adding a new child to the bus.  The resource is allocated from the
3126  * parent bus when it is reserved.  The resource list entry is marked
3127  * with RLE_RESERVED to note that it is a reserved resource.
3128  *
3129  * Subsequent attempts to allocate the resource with
3130  * resource_list_alloc() will succeed the first time and will set
3131  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3132  * resource that has been allocated is released with
3133  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3134  * the actual resource remains allocated.  The resource can be released to
3135  * the parent bus by calling resource_list_unreserve().
3136  *
3137  * @param rl		the resource list to allocate from
3138  * @param bus		the parent device of @p child
3139  * @param child		the device for which the resource is being reserved
3140  * @param type		the type of resource to allocate
3141  * @param rid		a pointer to the resource identifier
3142  * @param start		hint at the start of the resource range - pass
3143  *			@c 0UL for any start address
3144  * @param end		hint at the end of the resource range - pass
3145  *			@c ~0UL for any end address
3146  * @param count		hint at the size of range required - pass @c 1
3147  *			for any size
3148  * @param flags		any extra flags to control the resource
3149  *			allocation - see @c RF_XXX flags in
3150  *			<sys/rman.h> for details
3151  *
3152  * @returns		the resource which was allocated or @c NULL if no
3153  *			resource could be allocated
3154  */
3155 struct resource *
3156 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3157     int type, int *rid, u_long start, u_long end, u_long count, u_int flags)
3158 {
3159 	struct resource_list_entry *rle = NULL;
3160 	int passthrough = (device_get_parent(child) != bus);
3161 	struct resource *r;
3162 
3163 	if (passthrough)
3164 		panic(
3165     "resource_list_reserve() should only be called for direct children");
3166 	if (flags & RF_ACTIVE)
3167 		panic(
3168     "resource_list_reserve() should only reserve inactive resources");
3169 
3170 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3171 	    flags);
3172 	if (r != NULL) {
3173 		rle = resource_list_find(rl, type, *rid);
3174 		rle->flags |= RLE_RESERVED;
3175 	}
3176 	return (r);
3177 }
3178 
3179 /**
3180  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3181  *
3182  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3183  * and passing the allocation up to the parent of @p bus. This assumes
3184  * that the first entry of @c device_get_ivars(child) is a struct
3185  * resource_list. This also handles 'passthrough' allocations where a
3186  * child is a remote descendant of bus by passing the allocation up to
3187  * the parent of bus.
3188  *
3189  * Typically, a bus driver would store a list of child resources
3190  * somewhere in the child device's ivars (see device_get_ivars()) and
3191  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3192  * then call resource_list_alloc() to perform the allocation.
3193  *
3194  * @param rl		the resource list to allocate from
3195  * @param bus		the parent device of @p child
3196  * @param child		the device which is requesting an allocation
3197  * @param type		the type of resource to allocate
3198  * @param rid		a pointer to the resource identifier
3199  * @param start		hint at the start of the resource range - pass
3200  *			@c 0UL for any start address
3201  * @param end		hint at the end of the resource range - pass
3202  *			@c ~0UL for any end address
3203  * @param count		hint at the size of range required - pass @c 1
3204  *			for any size
3205  * @param flags		any extra flags to control the resource
3206  *			allocation - see @c RF_XXX flags in
3207  *			<sys/rman.h> for details
3208  *
3209  * @returns		the resource which was allocated or @c NULL if no
3210  *			resource could be allocated
3211  */
3212 struct resource *
3213 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3214     int type, int *rid, u_long start, u_long end, u_long count, u_int flags)
3215 {
3216 	struct resource_list_entry *rle = NULL;
3217 	int passthrough = (device_get_parent(child) != bus);
3218 	int isdefault = (start == 0UL && end == ~0UL);
3219 
3220 	if (passthrough) {
3221 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3222 		    type, rid, start, end, count, flags));
3223 	}
3224 
3225 	rle = resource_list_find(rl, type, *rid);
3226 
3227 	if (!rle)
3228 		return (NULL);		/* no resource of that type/rid */
3229 
3230 	if (rle->res) {
3231 		if (rle->flags & RLE_RESERVED) {
3232 			if (rle->flags & RLE_ALLOCATED)
3233 				return (NULL);
3234 			if ((flags & RF_ACTIVE) &&
3235 			    bus_activate_resource(child, type, *rid,
3236 			    rle->res) != 0)
3237 				return (NULL);
3238 			rle->flags |= RLE_ALLOCATED;
3239 			return (rle->res);
3240 		}
3241 		panic("resource_list_alloc: resource entry is busy");
3242 	}
3243 
3244 	if (isdefault) {
3245 		start = rle->start;
3246 		count = ulmax(count, rle->count);
3247 		end = ulmax(rle->end, start + count - 1);
3248 	}
3249 
3250 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3251 	    type, rid, start, end, count, flags);
3252 
3253 	/*
3254 	 * Record the new range.
3255 	 */
3256 	if (rle->res) {
3257 		rle->start = rman_get_start(rle->res);
3258 		rle->end = rman_get_end(rle->res);
3259 		rle->count = count;
3260 	}
3261 
3262 	return (rle->res);
3263 }
3264 
3265 /**
3266  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3267  *
3268  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3269  * used with resource_list_alloc().
3270  *
3271  * @param rl		the resource list which was allocated from
3272  * @param bus		the parent device of @p child
3273  * @param child		the device which is requesting a release
3274  * @param type		the type of resource to release
3275  * @param rid		the resource identifier
3276  * @param res		the resource to release
3277  *
3278  * @retval 0		success
3279  * @retval non-zero	a standard unix error code indicating what
3280  *			error condition prevented the operation
3281  */
3282 int
3283 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3284     int type, int rid, struct resource *res)
3285 {
3286 	struct resource_list_entry *rle = NULL;
3287 	int passthrough = (device_get_parent(child) != bus);
3288 	int error;
3289 
3290 	if (passthrough) {
3291 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3292 		    type, rid, res));
3293 	}
3294 
3295 	rle = resource_list_find(rl, type, rid);
3296 
3297 	if (!rle)
3298 		panic("resource_list_release: can't find resource");
3299 	if (!rle->res)
3300 		panic("resource_list_release: resource entry is not busy");
3301 	if (rle->flags & RLE_RESERVED) {
3302 		if (rle->flags & RLE_ALLOCATED) {
3303 			if (rman_get_flags(res) & RF_ACTIVE) {
3304 				error = bus_deactivate_resource(child, type,
3305 				    rid, res);
3306 				if (error)
3307 					return (error);
3308 			}
3309 			rle->flags &= ~RLE_ALLOCATED;
3310 			return (0);
3311 		}
3312 		return (EINVAL);
3313 	}
3314 
3315 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3316 	    type, rid, res);
3317 	if (error)
3318 		return (error);
3319 
3320 	rle->res = NULL;
3321 	return (0);
3322 }
3323 
3324 /**
3325  * @brief Release all active resources of a given type
3326  *
3327  * Release all active resources of a specified type.  This is intended
3328  * to be used to cleanup resources leaked by a driver after detach or
3329  * a failed attach.
3330  *
3331  * @param rl		the resource list which was allocated from
3332  * @param bus		the parent device of @p child
3333  * @param child		the device whose active resources are being released
3334  * @param type		the type of resources to release
3335  *
3336  * @retval 0		success
3337  * @retval EBUSY	at least one resource was active
3338  */
3339 int
3340 resource_list_release_active(struct resource_list *rl, device_t bus,
3341     device_t child, int type)
3342 {
3343 	struct resource_list_entry *rle;
3344 	int error, retval;
3345 
3346 	retval = 0;
3347 	STAILQ_FOREACH(rle, rl, link) {
3348 		if (rle->type != type)
3349 			continue;
3350 		if (rle->res == NULL)
3351 			continue;
3352 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3353 		    RLE_RESERVED)
3354 			continue;
3355 		retval = EBUSY;
3356 		error = resource_list_release(rl, bus, child, type,
3357 		    rman_get_rid(rle->res), rle->res);
3358 		if (error != 0)
3359 			device_printf(bus,
3360 			    "Failed to release active resource: %d\n", error);
3361 	}
3362 	return (retval);
3363 }
3364 
3365 
3366 /**
3367  * @brief Fully release a reserved resource
3368  *
3369  * Fully releases a resource reserved via resource_list_reserve().
3370  *
3371  * @param rl		the resource list which was allocated from
3372  * @param bus		the parent device of @p child
3373  * @param child		the device whose reserved resource is being released
3374  * @param type		the type of resource to release
3375  * @param rid		the resource identifier
3376  * @param res		the resource to release
3377  *
3378  * @retval 0		success
3379  * @retval non-zero	a standard unix error code indicating what
3380  *			error condition prevented the operation
3381  */
3382 int
3383 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3384     int type, int rid)
3385 {
3386 	struct resource_list_entry *rle = NULL;
3387 	int passthrough = (device_get_parent(child) != bus);
3388 
3389 	if (passthrough)
3390 		panic(
3391     "resource_list_unreserve() should only be called for direct children");
3392 
3393 	rle = resource_list_find(rl, type, rid);
3394 
3395 	if (!rle)
3396 		panic("resource_list_unreserve: can't find resource");
3397 	if (!(rle->flags & RLE_RESERVED))
3398 		return (EINVAL);
3399 	if (rle->flags & RLE_ALLOCATED)
3400 		return (EBUSY);
3401 	rle->flags &= ~RLE_RESERVED;
3402 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3403 }
3404 
3405 /**
3406  * @brief Print a description of resources in a resource list
3407  *
3408  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3409  * The name is printed if at least one resource of the given type is available.
3410  * The format is used to print resource start and end.
3411  *
3412  * @param rl		the resource list to print
3413  * @param name		the name of @p type, e.g. @c "memory"
3414  * @param type		type type of resource entry to print
3415  * @param format	printf(9) format string to print resource
3416  *			start and end values
3417  *
3418  * @returns		the number of characters printed
3419  */
3420 int
3421 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3422     const char *format)
3423 {
3424 	struct resource_list_entry *rle;
3425 	int printed, retval;
3426 
3427 	printed = 0;
3428 	retval = 0;
3429 	/* Yes, this is kinda cheating */
3430 	STAILQ_FOREACH(rle, rl, link) {
3431 		if (rle->type == type) {
3432 			if (printed == 0)
3433 				retval += printf(" %s ", name);
3434 			else
3435 				retval += printf(",");
3436 			printed++;
3437 			retval += printf(format, rle->start);
3438 			if (rle->count > 1) {
3439 				retval += printf("-");
3440 				retval += printf(format, rle->start +
3441 						 rle->count - 1);
3442 			}
3443 		}
3444 	}
3445 	return (retval);
3446 }
3447 
3448 /**
3449  * @brief Releases all the resources in a list.
3450  *
3451  * @param rl		The resource list to purge.
3452  *
3453  * @returns		nothing
3454  */
3455 void
3456 resource_list_purge(struct resource_list *rl)
3457 {
3458 	struct resource_list_entry *rle;
3459 
3460 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3461 		if (rle->res)
3462 			bus_release_resource(rman_get_device(rle->res),
3463 			    rle->type, rle->rid, rle->res);
3464 		STAILQ_REMOVE_HEAD(rl, link);
3465 		free(rle, M_BUS);
3466 	}
3467 }
3468 
3469 device_t
3470 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3471 {
3472 
3473 	return (device_add_child_ordered(dev, order, name, unit));
3474 }
3475 
3476 /**
3477  * @brief Helper function for implementing DEVICE_PROBE()
3478  *
3479  * This function can be used to help implement the DEVICE_PROBE() for
3480  * a bus (i.e. a device which has other devices attached to it). It
3481  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3482  * devclass.
3483  */
3484 int
3485 bus_generic_probe(device_t dev)
3486 {
3487 	devclass_t dc = dev->devclass;
3488 	driverlink_t dl;
3489 
3490 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3491 		/*
3492 		 * If this driver's pass is too high, then ignore it.
3493 		 * For most drivers in the default pass, this will
3494 		 * never be true.  For early-pass drivers they will
3495 		 * only call the identify routines of eligible drivers
3496 		 * when this routine is called.  Drivers for later
3497 		 * passes should have their identify routines called
3498 		 * on early-pass busses during BUS_NEW_PASS().
3499 		 */
3500 		if (dl->pass > bus_current_pass)
3501 			continue;
3502 		DEVICE_IDENTIFY(dl->driver, dev);
3503 	}
3504 
3505 	return (0);
3506 }
3507 
3508 /**
3509  * @brief Helper function for implementing DEVICE_ATTACH()
3510  *
3511  * This function can be used to help implement the DEVICE_ATTACH() for
3512  * a bus. It calls device_probe_and_attach() for each of the device's
3513  * children.
3514  */
3515 int
3516 bus_generic_attach(device_t dev)
3517 {
3518 	device_t child;
3519 
3520 	TAILQ_FOREACH(child, &dev->children, link) {
3521 		device_probe_and_attach(child);
3522 	}
3523 
3524 	return (0);
3525 }
3526 
3527 /**
3528  * @brief Helper function for implementing DEVICE_DETACH()
3529  *
3530  * This function can be used to help implement the DEVICE_DETACH() for
3531  * a bus. It calls device_detach() for each of the device's
3532  * children.
3533  */
3534 int
3535 bus_generic_detach(device_t dev)
3536 {
3537 	device_t child;
3538 	int error;
3539 
3540 	if (dev->state != DS_ATTACHED)
3541 		return (EBUSY);
3542 
3543 	TAILQ_FOREACH(child, &dev->children, link) {
3544 		if ((error = device_detach(child)) != 0)
3545 			return (error);
3546 	}
3547 
3548 	return (0);
3549 }
3550 
3551 /**
3552  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3553  *
3554  * This function can be used to help implement the DEVICE_SHUTDOWN()
3555  * for a bus. It calls device_shutdown() for each of the device's
3556  * children.
3557  */
3558 int
3559 bus_generic_shutdown(device_t dev)
3560 {
3561 	device_t child;
3562 
3563 	TAILQ_FOREACH(child, &dev->children, link) {
3564 		device_shutdown(child);
3565 	}
3566 
3567 	return (0);
3568 }
3569 
3570 /**
3571  * @brief Helper function for implementing DEVICE_SUSPEND()
3572  *
3573  * This function can be used to help implement the DEVICE_SUSPEND()
3574  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3575  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3576  * operation is aborted and any devices which were suspended are
3577  * resumed immediately by calling their DEVICE_RESUME() methods.
3578  */
3579 int
3580 bus_generic_suspend(device_t dev)
3581 {
3582 	int		error;
3583 	device_t	child, child2;
3584 
3585 	TAILQ_FOREACH(child, &dev->children, link) {
3586 		error = DEVICE_SUSPEND(child);
3587 		if (error) {
3588 			for (child2 = TAILQ_FIRST(&dev->children);
3589 			     child2 && child2 != child;
3590 			     child2 = TAILQ_NEXT(child2, link))
3591 				DEVICE_RESUME(child2);
3592 			return (error);
3593 		}
3594 	}
3595 	return (0);
3596 }
3597 
3598 /**
3599  * @brief Helper function for implementing DEVICE_RESUME()
3600  *
3601  * This function can be used to help implement the DEVICE_RESUME() for
3602  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3603  */
3604 int
3605 bus_generic_resume(device_t dev)
3606 {
3607 	device_t	child;
3608 
3609 	TAILQ_FOREACH(child, &dev->children, link) {
3610 		DEVICE_RESUME(child);
3611 		/* if resume fails, there's nothing we can usefully do... */
3612 	}
3613 	return (0);
3614 }
3615 
3616 /**
3617  * @brief Helper function for implementing BUS_PRINT_CHILD().
3618  *
3619  * This function prints the first part of the ascii representation of
3620  * @p child, including its name, unit and description (if any - see
3621  * device_set_desc()).
3622  *
3623  * @returns the number of characters printed
3624  */
3625 int
3626 bus_print_child_header(device_t dev, device_t child)
3627 {
3628 	int	retval = 0;
3629 
3630 	if (device_get_desc(child)) {
3631 		retval += device_printf(child, "<%s>", device_get_desc(child));
3632 	} else {
3633 		retval += printf("%s", device_get_nameunit(child));
3634 	}
3635 
3636 	return (retval);
3637 }
3638 
3639 /**
3640  * @brief Helper function for implementing BUS_PRINT_CHILD().
3641  *
3642  * This function prints the last part of the ascii representation of
3643  * @p child, which consists of the string @c " on " followed by the
3644  * name and unit of the @p dev.
3645  *
3646  * @returns the number of characters printed
3647  */
3648 int
3649 bus_print_child_footer(device_t dev, device_t child)
3650 {
3651 	return (printf(" on %s\n", device_get_nameunit(dev)));
3652 }
3653 
3654 /**
3655  * @brief Helper function for implementing BUS_PRINT_CHILD().
3656  *
3657  * This function simply calls bus_print_child_header() followed by
3658  * bus_print_child_footer().
3659  *
3660  * @returns the number of characters printed
3661  */
3662 int
3663 bus_generic_print_child(device_t dev, device_t child)
3664 {
3665 	int	retval = 0;
3666 
3667 	retval += bus_print_child_header(dev, child);
3668 	retval += bus_print_child_footer(dev, child);
3669 
3670 	return (retval);
3671 }
3672 
3673 /**
3674  * @brief Stub function for implementing BUS_READ_IVAR().
3675  *
3676  * @returns ENOENT
3677  */
3678 int
3679 bus_generic_read_ivar(device_t dev, device_t child, int index,
3680     uintptr_t * result)
3681 {
3682 	return (ENOENT);
3683 }
3684 
3685 /**
3686  * @brief Stub function for implementing BUS_WRITE_IVAR().
3687  *
3688  * @returns ENOENT
3689  */
3690 int
3691 bus_generic_write_ivar(device_t dev, device_t child, int index,
3692     uintptr_t value)
3693 {
3694 	return (ENOENT);
3695 }
3696 
3697 /**
3698  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
3699  *
3700  * @returns NULL
3701  */
3702 struct resource_list *
3703 bus_generic_get_resource_list(device_t dev, device_t child)
3704 {
3705 	return (NULL);
3706 }
3707 
3708 /**
3709  * @brief Helper function for implementing BUS_DRIVER_ADDED().
3710  *
3711  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
3712  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
3713  * and then calls device_probe_and_attach() for each unattached child.
3714  */
3715 void
3716 bus_generic_driver_added(device_t dev, driver_t *driver)
3717 {
3718 	device_t child;
3719 
3720 	DEVICE_IDENTIFY(driver, dev);
3721 	TAILQ_FOREACH(child, &dev->children, link) {
3722 		if (child->state == DS_NOTPRESENT ||
3723 		    (child->flags & DF_REBID))
3724 			device_probe_and_attach(child);
3725 	}
3726 }
3727 
3728 /**
3729  * @brief Helper function for implementing BUS_NEW_PASS().
3730  *
3731  * This implementing of BUS_NEW_PASS() first calls the identify
3732  * routines for any drivers that probe at the current pass.  Then it
3733  * walks the list of devices for this bus.  If a device is already
3734  * attached, then it calls BUS_NEW_PASS() on that device.  If the
3735  * device is not already attached, it attempts to attach a driver to
3736  * it.
3737  */
3738 void
3739 bus_generic_new_pass(device_t dev)
3740 {
3741 	driverlink_t dl;
3742 	devclass_t dc;
3743 	device_t child;
3744 
3745 	dc = dev->devclass;
3746 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3747 		if (dl->pass == bus_current_pass)
3748 			DEVICE_IDENTIFY(dl->driver, dev);
3749 	}
3750 	TAILQ_FOREACH(child, &dev->children, link) {
3751 		if (child->state >= DS_ATTACHED)
3752 			BUS_NEW_PASS(child);
3753 		else if (child->state == DS_NOTPRESENT)
3754 			device_probe_and_attach(child);
3755 	}
3756 }
3757 
3758 /**
3759  * @brief Helper function for implementing BUS_SETUP_INTR().
3760  *
3761  * This simple implementation of BUS_SETUP_INTR() simply calls the
3762  * BUS_SETUP_INTR() method of the parent of @p dev.
3763  */
3764 int
3765 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
3766     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
3767     void **cookiep)
3768 {
3769 	/* Propagate up the bus hierarchy until someone handles it. */
3770 	if (dev->parent)
3771 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
3772 		    filter, intr, arg, cookiep));
3773 	return (EINVAL);
3774 }
3775 
3776 /**
3777  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
3778  *
3779  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
3780  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
3781  */
3782 int
3783 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
3784     void *cookie)
3785 {
3786 	/* Propagate up the bus hierarchy until someone handles it. */
3787 	if (dev->parent)
3788 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
3789 	return (EINVAL);
3790 }
3791 
3792 /**
3793  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
3794  *
3795  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
3796  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
3797  */
3798 int
3799 bus_generic_adjust_resource(device_t dev, device_t child, int type,
3800     struct resource *r, u_long start, u_long end)
3801 {
3802 	/* Propagate up the bus hierarchy until someone handles it. */
3803 	if (dev->parent)
3804 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
3805 		    end));
3806 	return (EINVAL);
3807 }
3808 
3809 /**
3810  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
3811  *
3812  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
3813  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
3814  */
3815 struct resource *
3816 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
3817     u_long start, u_long end, u_long count, u_int flags)
3818 {
3819 	/* Propagate up the bus hierarchy until someone handles it. */
3820 	if (dev->parent)
3821 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
3822 		    start, end, count, flags));
3823 	return (NULL);
3824 }
3825 
3826 /**
3827  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
3828  *
3829  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
3830  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
3831  */
3832 int
3833 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
3834     struct resource *r)
3835 {
3836 	/* Propagate up the bus hierarchy until someone handles it. */
3837 	if (dev->parent)
3838 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
3839 		    r));
3840 	return (EINVAL);
3841 }
3842 
3843 /**
3844  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
3845  *
3846  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
3847  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
3848  */
3849 int
3850 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
3851     struct resource *r)
3852 {
3853 	/* Propagate up the bus hierarchy until someone handles it. */
3854 	if (dev->parent)
3855 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
3856 		    r));
3857 	return (EINVAL);
3858 }
3859 
3860 /**
3861  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
3862  *
3863  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
3864  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
3865  */
3866 int
3867 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
3868     int rid, struct resource *r)
3869 {
3870 	/* Propagate up the bus hierarchy until someone handles it. */
3871 	if (dev->parent)
3872 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
3873 		    r));
3874 	return (EINVAL);
3875 }
3876 
3877 /**
3878  * @brief Helper function for implementing BUS_BIND_INTR().
3879  *
3880  * This simple implementation of BUS_BIND_INTR() simply calls the
3881  * BUS_BIND_INTR() method of the parent of @p dev.
3882  */
3883 int
3884 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
3885     int cpu)
3886 {
3887 
3888 	/* Propagate up the bus hierarchy until someone handles it. */
3889 	if (dev->parent)
3890 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
3891 	return (EINVAL);
3892 }
3893 
3894 /**
3895  * @brief Helper function for implementing BUS_CONFIG_INTR().
3896  *
3897  * This simple implementation of BUS_CONFIG_INTR() simply calls the
3898  * BUS_CONFIG_INTR() method of the parent of @p dev.
3899  */
3900 int
3901 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
3902     enum intr_polarity pol)
3903 {
3904 
3905 	/* Propagate up the bus hierarchy until someone handles it. */
3906 	if (dev->parent)
3907 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
3908 	return (EINVAL);
3909 }
3910 
3911 /**
3912  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
3913  *
3914  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
3915  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
3916  */
3917 int
3918 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
3919     void *cookie, const char *descr)
3920 {
3921 
3922 	/* Propagate up the bus hierarchy until someone handles it. */
3923 	if (dev->parent)
3924 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
3925 		    descr));
3926 	return (EINVAL);
3927 }
3928 
3929 /**
3930  * @brief Helper function for implementing BUS_GET_DMA_TAG().
3931  *
3932  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
3933  * BUS_GET_DMA_TAG() method of the parent of @p dev.
3934  */
3935 bus_dma_tag_t
3936 bus_generic_get_dma_tag(device_t dev, device_t child)
3937 {
3938 
3939 	/* Propagate up the bus hierarchy until someone handles it. */
3940 	if (dev->parent != NULL)
3941 		return (BUS_GET_DMA_TAG(dev->parent, child));
3942 	return (NULL);
3943 }
3944 
3945 /**
3946  * @brief Helper function for implementing BUS_GET_RESOURCE().
3947  *
3948  * This implementation of BUS_GET_RESOURCE() uses the
3949  * resource_list_find() function to do most of the work. It calls
3950  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3951  * search.
3952  */
3953 int
3954 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
3955     u_long *startp, u_long *countp)
3956 {
3957 	struct resource_list *		rl = NULL;
3958 	struct resource_list_entry *	rle = NULL;
3959 
3960 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3961 	if (!rl)
3962 		return (EINVAL);
3963 
3964 	rle = resource_list_find(rl, type, rid);
3965 	if (!rle)
3966 		return (ENOENT);
3967 
3968 	if (startp)
3969 		*startp = rle->start;
3970 	if (countp)
3971 		*countp = rle->count;
3972 
3973 	return (0);
3974 }
3975 
3976 /**
3977  * @brief Helper function for implementing BUS_SET_RESOURCE().
3978  *
3979  * This implementation of BUS_SET_RESOURCE() uses the
3980  * resource_list_add() function to do most of the work. It calls
3981  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
3982  * edit.
3983  */
3984 int
3985 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
3986     u_long start, u_long count)
3987 {
3988 	struct resource_list *		rl = NULL;
3989 
3990 	rl = BUS_GET_RESOURCE_LIST(dev, child);
3991 	if (!rl)
3992 		return (EINVAL);
3993 
3994 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
3995 
3996 	return (0);
3997 }
3998 
3999 /**
4000  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4001  *
4002  * This implementation of BUS_DELETE_RESOURCE() uses the
4003  * resource_list_delete() function to do most of the work. It calls
4004  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4005  * edit.
4006  */
4007 void
4008 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4009 {
4010 	struct resource_list *		rl = NULL;
4011 
4012 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4013 	if (!rl)
4014 		return;
4015 
4016 	resource_list_delete(rl, type, rid);
4017 
4018 	return;
4019 }
4020 
4021 /**
4022  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4023  *
4024  * This implementation of BUS_RELEASE_RESOURCE() uses the
4025  * resource_list_release() function to do most of the work. It calls
4026  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4027  */
4028 int
4029 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4030     int rid, struct resource *r)
4031 {
4032 	struct resource_list *		rl = NULL;
4033 
4034 	if (device_get_parent(child) != dev)
4035 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4036 		    type, rid, r));
4037 
4038 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4039 	if (!rl)
4040 		return (EINVAL);
4041 
4042 	return (resource_list_release(rl, dev, child, type, rid, r));
4043 }
4044 
4045 /**
4046  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4047  *
4048  * This implementation of BUS_ALLOC_RESOURCE() uses the
4049  * resource_list_alloc() function to do most of the work. It calls
4050  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4051  */
4052 struct resource *
4053 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4054     int *rid, u_long start, u_long end, u_long count, u_int flags)
4055 {
4056 	struct resource_list *		rl = NULL;
4057 
4058 	if (device_get_parent(child) != dev)
4059 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4060 		    type, rid, start, end, count, flags));
4061 
4062 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4063 	if (!rl)
4064 		return (NULL);
4065 
4066 	return (resource_list_alloc(rl, dev, child, type, rid,
4067 	    start, end, count, flags));
4068 }
4069 
4070 /**
4071  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4072  *
4073  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4074  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4075  */
4076 int
4077 bus_generic_child_present(device_t dev, device_t child)
4078 {
4079 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4080 }
4081 
4082 /*
4083  * Some convenience functions to make it easier for drivers to use the
4084  * resource-management functions.  All these really do is hide the
4085  * indirection through the parent's method table, making for slightly
4086  * less-wordy code.  In the future, it might make sense for this code
4087  * to maintain some sort of a list of resources allocated by each device.
4088  */
4089 
4090 int
4091 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4092     struct resource **res)
4093 {
4094 	int i;
4095 
4096 	for (i = 0; rs[i].type != -1; i++)
4097 		res[i] = NULL;
4098 	for (i = 0; rs[i].type != -1; i++) {
4099 		res[i] = bus_alloc_resource_any(dev,
4100 		    rs[i].type, &rs[i].rid, rs[i].flags);
4101 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4102 			bus_release_resources(dev, rs, res);
4103 			return (ENXIO);
4104 		}
4105 	}
4106 	return (0);
4107 }
4108 
4109 void
4110 bus_release_resources(device_t dev, const struct resource_spec *rs,
4111     struct resource **res)
4112 {
4113 	int i;
4114 
4115 	for (i = 0; rs[i].type != -1; i++)
4116 		if (res[i] != NULL) {
4117 			bus_release_resource(
4118 			    dev, rs[i].type, rs[i].rid, res[i]);
4119 			res[i] = NULL;
4120 		}
4121 }
4122 
4123 /**
4124  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4125  *
4126  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4127  * parent of @p dev.
4128  */
4129 struct resource *
4130 bus_alloc_resource(device_t dev, int type, int *rid, u_long start, u_long end,
4131     u_long count, u_int flags)
4132 {
4133 	if (dev->parent == NULL)
4134 		return (NULL);
4135 	return (BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4136 	    count, flags));
4137 }
4138 
4139 /**
4140  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4141  *
4142  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4143  * parent of @p dev.
4144  */
4145 int
4146 bus_adjust_resource(device_t dev, int type, struct resource *r, u_long start,
4147     u_long end)
4148 {
4149 	if (dev->parent == NULL)
4150 		return (EINVAL);
4151 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4152 }
4153 
4154 /**
4155  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4156  *
4157  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4158  * parent of @p dev.
4159  */
4160 int
4161 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4162 {
4163 	if (dev->parent == NULL)
4164 		return (EINVAL);
4165 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4166 }
4167 
4168 /**
4169  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4170  *
4171  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4172  * parent of @p dev.
4173  */
4174 int
4175 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4176 {
4177 	if (dev->parent == NULL)
4178 		return (EINVAL);
4179 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4180 }
4181 
4182 /**
4183  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4184  *
4185  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4186  * parent of @p dev.
4187  */
4188 int
4189 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4190 {
4191 	if (dev->parent == NULL)
4192 		return (EINVAL);
4193 	return (BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r));
4194 }
4195 
4196 /**
4197  * @brief Wrapper function for BUS_SETUP_INTR().
4198  *
4199  * This function simply calls the BUS_SETUP_INTR() method of the
4200  * parent of @p dev.
4201  */
4202 int
4203 bus_setup_intr(device_t dev, struct resource *r, int flags,
4204     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4205 {
4206 	int error;
4207 
4208 	if (dev->parent == NULL)
4209 		return (EINVAL);
4210 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4211 	    arg, cookiep);
4212 	if (error != 0)
4213 		return (error);
4214 	if (handler != NULL && !(flags & INTR_MPSAFE))
4215 		device_printf(dev, "[GIANT-LOCKED]\n");
4216 	return (0);
4217 }
4218 
4219 /**
4220  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4221  *
4222  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4223  * parent of @p dev.
4224  */
4225 int
4226 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4227 {
4228 	if (dev->parent == NULL)
4229 		return (EINVAL);
4230 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4231 }
4232 
4233 /**
4234  * @brief Wrapper function for BUS_BIND_INTR().
4235  *
4236  * This function simply calls the BUS_BIND_INTR() method of the
4237  * parent of @p dev.
4238  */
4239 int
4240 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4241 {
4242 	if (dev->parent == NULL)
4243 		return (EINVAL);
4244 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4245 }
4246 
4247 /**
4248  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4249  *
4250  * This function first formats the requested description into a
4251  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4252  * the parent of @p dev.
4253  */
4254 int
4255 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4256     const char *fmt, ...)
4257 {
4258 	va_list ap;
4259 	char descr[MAXCOMLEN + 1];
4260 
4261 	if (dev->parent == NULL)
4262 		return (EINVAL);
4263 	va_start(ap, fmt);
4264 	vsnprintf(descr, sizeof(descr), fmt, ap);
4265 	va_end(ap);
4266 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4267 }
4268 
4269 /**
4270  * @brief Wrapper function for BUS_SET_RESOURCE().
4271  *
4272  * This function simply calls the BUS_SET_RESOURCE() method of the
4273  * parent of @p dev.
4274  */
4275 int
4276 bus_set_resource(device_t dev, int type, int rid,
4277     u_long start, u_long count)
4278 {
4279 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4280 	    start, count));
4281 }
4282 
4283 /**
4284  * @brief Wrapper function for BUS_GET_RESOURCE().
4285  *
4286  * This function simply calls the BUS_GET_RESOURCE() method of the
4287  * parent of @p dev.
4288  */
4289 int
4290 bus_get_resource(device_t dev, int type, int rid,
4291     u_long *startp, u_long *countp)
4292 {
4293 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4294 	    startp, countp));
4295 }
4296 
4297 /**
4298  * @brief Wrapper function for BUS_GET_RESOURCE().
4299  *
4300  * This function simply calls the BUS_GET_RESOURCE() method of the
4301  * parent of @p dev and returns the start value.
4302  */
4303 u_long
4304 bus_get_resource_start(device_t dev, int type, int rid)
4305 {
4306 	u_long start, count;
4307 	int error;
4308 
4309 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4310 	    &start, &count);
4311 	if (error)
4312 		return (0);
4313 	return (start);
4314 }
4315 
4316 /**
4317  * @brief Wrapper function for BUS_GET_RESOURCE().
4318  *
4319  * This function simply calls the BUS_GET_RESOURCE() method of the
4320  * parent of @p dev and returns the count value.
4321  */
4322 u_long
4323 bus_get_resource_count(device_t dev, int type, int rid)
4324 {
4325 	u_long start, count;
4326 	int error;
4327 
4328 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4329 	    &start, &count);
4330 	if (error)
4331 		return (0);
4332 	return (count);
4333 }
4334 
4335 /**
4336  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4337  *
4338  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4339  * parent of @p dev.
4340  */
4341 void
4342 bus_delete_resource(device_t dev, int type, int rid)
4343 {
4344 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4345 }
4346 
4347 /**
4348  * @brief Wrapper function for BUS_CHILD_PRESENT().
4349  *
4350  * This function simply calls the BUS_CHILD_PRESENT() method of the
4351  * parent of @p dev.
4352  */
4353 int
4354 bus_child_present(device_t child)
4355 {
4356 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4357 }
4358 
4359 /**
4360  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4361  *
4362  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4363  * parent of @p dev.
4364  */
4365 int
4366 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4367 {
4368 	device_t parent;
4369 
4370 	parent = device_get_parent(child);
4371 	if (parent == NULL) {
4372 		*buf = '\0';
4373 		return (0);
4374 	}
4375 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4376 }
4377 
4378 /**
4379  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4380  *
4381  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4382  * parent of @p dev.
4383  */
4384 int
4385 bus_child_location_str(device_t child, char *buf, size_t buflen)
4386 {
4387 	device_t parent;
4388 
4389 	parent = device_get_parent(child);
4390 	if (parent == NULL) {
4391 		*buf = '\0';
4392 		return (0);
4393 	}
4394 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4395 }
4396 
4397 /**
4398  * @brief Wrapper function for BUS_GET_DMA_TAG().
4399  *
4400  * This function simply calls the BUS_GET_DMA_TAG() method of the
4401  * parent of @p dev.
4402  */
4403 bus_dma_tag_t
4404 bus_get_dma_tag(device_t dev)
4405 {
4406 	device_t parent;
4407 
4408 	parent = device_get_parent(dev);
4409 	if (parent == NULL)
4410 		return (NULL);
4411 	return (BUS_GET_DMA_TAG(parent, dev));
4412 }
4413 
4414 /* Resume all devices and then notify userland that we're up again. */
4415 static int
4416 root_resume(device_t dev)
4417 {
4418 	int error;
4419 
4420 	error = bus_generic_resume(dev);
4421 	if (error == 0)
4422 		devctl_notify("kern", "power", "resume", NULL);
4423 	return (error);
4424 }
4425 
4426 static int
4427 root_print_child(device_t dev, device_t child)
4428 {
4429 	int	retval = 0;
4430 
4431 	retval += bus_print_child_header(dev, child);
4432 	retval += printf("\n");
4433 
4434 	return (retval);
4435 }
4436 
4437 static int
4438 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
4439     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
4440 {
4441 	/*
4442 	 * If an interrupt mapping gets to here something bad has happened.
4443 	 */
4444 	panic("root_setup_intr");
4445 }
4446 
4447 /*
4448  * If we get here, assume that the device is permanant and really is
4449  * present in the system.  Removable bus drivers are expected to intercept
4450  * this call long before it gets here.  We return -1 so that drivers that
4451  * really care can check vs -1 or some ERRNO returned higher in the food
4452  * chain.
4453  */
4454 static int
4455 root_child_present(device_t dev, device_t child)
4456 {
4457 	return (-1);
4458 }
4459 
4460 static kobj_method_t root_methods[] = {
4461 	/* Device interface */
4462 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
4463 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
4464 	KOBJMETHOD(device_resume,	root_resume),
4465 
4466 	/* Bus interface */
4467 	KOBJMETHOD(bus_print_child,	root_print_child),
4468 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
4469 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
4470 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
4471 	KOBJMETHOD(bus_child_present,	root_child_present),
4472 
4473 	KOBJMETHOD_END
4474 };
4475 
4476 static driver_t root_driver = {
4477 	"root",
4478 	root_methods,
4479 	1,			/* no softc */
4480 };
4481 
4482 device_t	root_bus;
4483 devclass_t	root_devclass;
4484 
4485 static int
4486 root_bus_module_handler(module_t mod, int what, void* arg)
4487 {
4488 	switch (what) {
4489 	case MOD_LOAD:
4490 		TAILQ_INIT(&bus_data_devices);
4491 		kobj_class_compile((kobj_class_t) &root_driver);
4492 		root_bus = make_device(NULL, "root", 0);
4493 		root_bus->desc = "System root bus";
4494 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
4495 		root_bus->driver = &root_driver;
4496 		root_bus->state = DS_ATTACHED;
4497 		root_devclass = devclass_find_internal("root", NULL, FALSE);
4498 		devinit();
4499 		return (0);
4500 
4501 	case MOD_SHUTDOWN:
4502 		device_shutdown(root_bus);
4503 		return (0);
4504 	default:
4505 		return (EOPNOTSUPP);
4506 	}
4507 
4508 	return (0);
4509 }
4510 
4511 static moduledata_t root_bus_mod = {
4512 	"rootbus",
4513 	root_bus_module_handler,
4514 	NULL
4515 };
4516 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
4517 
4518 /**
4519  * @brief Automatically configure devices
4520  *
4521  * This function begins the autoconfiguration process by calling
4522  * device_probe_and_attach() for each child of the @c root0 device.
4523  */
4524 void
4525 root_bus_configure(void)
4526 {
4527 
4528 	PDEBUG(("."));
4529 
4530 	/* Eventually this will be split up, but this is sufficient for now. */
4531 	bus_set_pass(BUS_PASS_DEFAULT);
4532 }
4533 
4534 /**
4535  * @brief Module handler for registering device drivers
4536  *
4537  * This module handler is used to automatically register device
4538  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
4539  * devclass_add_driver() for the driver described by the
4540  * driver_module_data structure pointed to by @p arg
4541  */
4542 int
4543 driver_module_handler(module_t mod, int what, void *arg)
4544 {
4545 	struct driver_module_data *dmd;
4546 	devclass_t bus_devclass;
4547 	kobj_class_t driver;
4548 	int error, pass;
4549 
4550 	dmd = (struct driver_module_data *)arg;
4551 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
4552 	error = 0;
4553 
4554 	switch (what) {
4555 	case MOD_LOAD:
4556 		if (dmd->dmd_chainevh)
4557 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4558 
4559 		pass = dmd->dmd_pass;
4560 		driver = dmd->dmd_driver;
4561 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
4562 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
4563 		error = devclass_add_driver(bus_devclass, driver, pass,
4564 		    dmd->dmd_devclass);
4565 		break;
4566 
4567 	case MOD_UNLOAD:
4568 		PDEBUG(("Unloading module: driver %s from bus %s",
4569 		    DRIVERNAME(dmd->dmd_driver),
4570 		    dmd->dmd_busname));
4571 		error = devclass_delete_driver(bus_devclass,
4572 		    dmd->dmd_driver);
4573 
4574 		if (!error && dmd->dmd_chainevh)
4575 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4576 		break;
4577 	case MOD_QUIESCE:
4578 		PDEBUG(("Quiesce module: driver %s from bus %s",
4579 		    DRIVERNAME(dmd->dmd_driver),
4580 		    dmd->dmd_busname));
4581 		error = devclass_quiesce_driver(bus_devclass,
4582 		    dmd->dmd_driver);
4583 
4584 		if (!error && dmd->dmd_chainevh)
4585 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4586 		break;
4587 	default:
4588 		error = EOPNOTSUPP;
4589 		break;
4590 	}
4591 
4592 	return (error);
4593 }
4594 
4595 /**
4596  * @brief Enumerate all hinted devices for this bus.
4597  *
4598  * Walks through the hints for this bus and calls the bus_hinted_child
4599  * routine for each one it fines.  It searches first for the specific
4600  * bus that's being probed for hinted children (eg isa0), and then for
4601  * generic children (eg isa).
4602  *
4603  * @param	dev	bus device to enumerate
4604  */
4605 void
4606 bus_enumerate_hinted_children(device_t bus)
4607 {
4608 	int i;
4609 	const char *dname, *busname;
4610 	int dunit;
4611 
4612 	/*
4613 	 * enumerate all devices on the specific bus
4614 	 */
4615 	busname = device_get_nameunit(bus);
4616 	i = 0;
4617 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
4618 		BUS_HINTED_CHILD(bus, dname, dunit);
4619 
4620 	/*
4621 	 * and all the generic ones.
4622 	 */
4623 	busname = device_get_name(bus);
4624 	i = 0;
4625 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
4626 		BUS_HINTED_CHILD(bus, dname, dunit);
4627 }
4628 
4629 #ifdef BUS_DEBUG
4630 
4631 /* the _short versions avoid iteration by not calling anything that prints
4632  * more than oneliners. I love oneliners.
4633  */
4634 
4635 static void
4636 print_device_short(device_t dev, int indent)
4637 {
4638 	if (!dev)
4639 		return;
4640 
4641 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
4642 	    dev->unit, dev->desc,
4643 	    (dev->parent? "":"no "),
4644 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
4645 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
4646 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
4647 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
4648 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
4649 	    (dev->flags&DF_REBID? "rebiddable,":""),
4650 	    (dev->ivars? "":"no "),
4651 	    (dev->softc? "":"no "),
4652 	    dev->busy));
4653 }
4654 
4655 static void
4656 print_device(device_t dev, int indent)
4657 {
4658 	if (!dev)
4659 		return;
4660 
4661 	print_device_short(dev, indent);
4662 
4663 	indentprintf(("Parent:\n"));
4664 	print_device_short(dev->parent, indent+1);
4665 	indentprintf(("Driver:\n"));
4666 	print_driver_short(dev->driver, indent+1);
4667 	indentprintf(("Devclass:\n"));
4668 	print_devclass_short(dev->devclass, indent+1);
4669 }
4670 
4671 void
4672 print_device_tree_short(device_t dev, int indent)
4673 /* print the device and all its children (indented) */
4674 {
4675 	device_t child;
4676 
4677 	if (!dev)
4678 		return;
4679 
4680 	print_device_short(dev, indent);
4681 
4682 	TAILQ_FOREACH(child, &dev->children, link) {
4683 		print_device_tree_short(child, indent+1);
4684 	}
4685 }
4686 
4687 void
4688 print_device_tree(device_t dev, int indent)
4689 /* print the device and all its children (indented) */
4690 {
4691 	device_t child;
4692 
4693 	if (!dev)
4694 		return;
4695 
4696 	print_device(dev, indent);
4697 
4698 	TAILQ_FOREACH(child, &dev->children, link) {
4699 		print_device_tree(child, indent+1);
4700 	}
4701 }
4702 
4703 static void
4704 print_driver_short(driver_t *driver, int indent)
4705 {
4706 	if (!driver)
4707 		return;
4708 
4709 	indentprintf(("driver %s: softc size = %zd\n",
4710 	    driver->name, driver->size));
4711 }
4712 
4713 static void
4714 print_driver(driver_t *driver, int indent)
4715 {
4716 	if (!driver)
4717 		return;
4718 
4719 	print_driver_short(driver, indent);
4720 }
4721 
4722 static void
4723 print_driver_list(driver_list_t drivers, int indent)
4724 {
4725 	driverlink_t driver;
4726 
4727 	TAILQ_FOREACH(driver, &drivers, link) {
4728 		print_driver(driver->driver, indent);
4729 	}
4730 }
4731 
4732 static void
4733 print_devclass_short(devclass_t dc, int indent)
4734 {
4735 	if ( !dc )
4736 		return;
4737 
4738 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
4739 }
4740 
4741 static void
4742 print_devclass(devclass_t dc, int indent)
4743 {
4744 	int i;
4745 
4746 	if ( !dc )
4747 		return;
4748 
4749 	print_devclass_short(dc, indent);
4750 	indentprintf(("Drivers:\n"));
4751 	print_driver_list(dc->drivers, indent+1);
4752 
4753 	indentprintf(("Devices:\n"));
4754 	for (i = 0; i < dc->maxunit; i++)
4755 		if (dc->devices[i])
4756 			print_device(dc->devices[i], indent+1);
4757 }
4758 
4759 void
4760 print_devclass_list_short(void)
4761 {
4762 	devclass_t dc;
4763 
4764 	printf("Short listing of devclasses, drivers & devices:\n");
4765 	TAILQ_FOREACH(dc, &devclasses, link) {
4766 		print_devclass_short(dc, 0);
4767 	}
4768 }
4769 
4770 void
4771 print_devclass_list(void)
4772 {
4773 	devclass_t dc;
4774 
4775 	printf("Full listing of devclasses, drivers & devices:\n");
4776 	TAILQ_FOREACH(dc, &devclasses, link) {
4777 		print_devclass(dc, 0);
4778 	}
4779 }
4780 
4781 #endif
4782 
4783 /*
4784  * User-space access to the device tree.
4785  *
4786  * We implement a small set of nodes:
4787  *
4788  * hw.bus			Single integer read method to obtain the
4789  *				current generation count.
4790  * hw.bus.devices		Reads the entire device tree in flat space.
4791  * hw.bus.rman			Resource manager interface
4792  *
4793  * We might like to add the ability to scan devclasses and/or drivers to
4794  * determine what else is currently loaded/available.
4795  */
4796 
4797 static int
4798 sysctl_bus(SYSCTL_HANDLER_ARGS)
4799 {
4800 	struct u_businfo	ubus;
4801 
4802 	ubus.ub_version = BUS_USER_VERSION;
4803 	ubus.ub_generation = bus_data_generation;
4804 
4805 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
4806 }
4807 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
4808     "bus-related data");
4809 
4810 static int
4811 sysctl_devices(SYSCTL_HANDLER_ARGS)
4812 {
4813 	int			*name = (int *)arg1;
4814 	u_int			namelen = arg2;
4815 	int			index;
4816 	struct device		*dev;
4817 	struct u_device		udev;	/* XXX this is a bit big */
4818 	int			error;
4819 
4820 	if (namelen != 2)
4821 		return (EINVAL);
4822 
4823 	if (bus_data_generation_check(name[0]))
4824 		return (EINVAL);
4825 
4826 	index = name[1];
4827 
4828 	/*
4829 	 * Scan the list of devices, looking for the requested index.
4830 	 */
4831 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
4832 		if (index-- == 0)
4833 			break;
4834 	}
4835 	if (dev == NULL)
4836 		return (ENOENT);
4837 
4838 	/*
4839 	 * Populate the return array.
4840 	 */
4841 	bzero(&udev, sizeof(udev));
4842 	udev.dv_handle = (uintptr_t)dev;
4843 	udev.dv_parent = (uintptr_t)dev->parent;
4844 	if (dev->nameunit != NULL)
4845 		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
4846 	if (dev->desc != NULL)
4847 		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
4848 	if (dev->driver != NULL && dev->driver->name != NULL)
4849 		strlcpy(udev.dv_drivername, dev->driver->name,
4850 		    sizeof(udev.dv_drivername));
4851 	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
4852 	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
4853 	udev.dv_devflags = dev->devflags;
4854 	udev.dv_flags = dev->flags;
4855 	udev.dv_state = dev->state;
4856 	error = SYSCTL_OUT(req, &udev, sizeof(udev));
4857 	return (error);
4858 }
4859 
4860 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
4861     "system device tree");
4862 
4863 int
4864 bus_data_generation_check(int generation)
4865 {
4866 	if (generation != bus_data_generation)
4867 		return (1);
4868 
4869 	/* XXX generate optimised lists here? */
4870 	return (0);
4871 }
4872 
4873 void
4874 bus_data_generation_update(void)
4875 {
4876 	bus_data_generation++;
4877 }
4878 
4879 int
4880 bus_free_resource(device_t dev, int type, struct resource *r)
4881 {
4882 	if (r == NULL)
4883 		return (0);
4884 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
4885 }
4886