xref: /freebsd/sys/kern/subr_bus.c (revision 3422ca83ba48e5c9174542a2d3ba8225275779a6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/rman.h>
55 #include <sys/sbuf.h>
56 #include <sys/selinfo.h>
57 #include <sys/signalvar.h>
58 #include <sys/smp.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61 #include <sys/uio.h>
62 #include <sys/bus.h>
63 #include <sys/cpuset.h>
64 
65 #include <net/vnet.h>
66 
67 #include <machine/cpu.h>
68 #include <machine/stdarg.h>
69 
70 #include <vm/uma.h>
71 #include <vm/vm.h>
72 
73 #include <ddb/ddb.h>
74 
75 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
76     NULL);
77 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
78     NULL);
79 
80 /*
81  * Used to attach drivers to devclasses.
82  */
83 typedef struct driverlink *driverlink_t;
84 struct driverlink {
85 	kobj_class_t	driver;
86 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
87 	int		pass;
88 	int		flags;
89 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
90 	TAILQ_ENTRY(driverlink) passlink;
91 };
92 
93 /*
94  * Forward declarations
95  */
96 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
97 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
98 typedef TAILQ_HEAD(device_list, device) device_list_t;
99 
100 struct devclass {
101 	TAILQ_ENTRY(devclass) link;
102 	devclass_t	parent;		/* parent in devclass hierarchy */
103 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
104 	char		*name;
105 	device_t	*devices;	/* array of devices indexed by unit */
106 	int		maxunit;	/* size of devices array */
107 	int		flags;
108 #define DC_HAS_CHILDREN		1
109 
110 	struct sysctl_ctx_list sysctl_ctx;
111 	struct sysctl_oid *sysctl_tree;
112 };
113 
114 /**
115  * @brief Implementation of device.
116  */
117 struct device {
118 	/*
119 	 * A device is a kernel object. The first field must be the
120 	 * current ops table for the object.
121 	 */
122 	KOBJ_FIELDS;
123 
124 	/*
125 	 * Device hierarchy.
126 	 */
127 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
128 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
129 	device_t	parent;		/**< parent of this device  */
130 	device_list_t	children;	/**< list of child devices */
131 
132 	/*
133 	 * Details of this device.
134 	 */
135 	driver_t	*driver;	/**< current driver */
136 	devclass_t	devclass;	/**< current device class */
137 	int		unit;		/**< current unit number */
138 	char*		nameunit;	/**< name+unit e.g. foodev0 */
139 	char*		desc;		/**< driver specific description */
140 	int		busy;		/**< count of calls to device_busy() */
141 	device_state_t	state;		/**< current device state  */
142 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
143 	u_int		flags;		/**< internal device flags  */
144 	u_int	order;			/**< order from device_add_child_ordered() */
145 	void	*ivars;			/**< instance variables  */
146 	void	*softc;			/**< current driver's variables  */
147 
148 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
149 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
150 };
151 
152 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
153 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
154 
155 EVENTHANDLER_LIST_DEFINE(device_attach);
156 EVENTHANDLER_LIST_DEFINE(device_detach);
157 EVENTHANDLER_LIST_DEFINE(dev_lookup);
158 
159 static void devctl2_init(void);
160 static bool device_frozen;
161 
162 #define DRIVERNAME(d)	((d)? d->name : "no driver")
163 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
164 
165 #ifdef BUS_DEBUG
166 
167 static int bus_debug = 1;
168 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
169     "Bus debug level");
170 
171 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
172 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
173 
174 /**
175  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
176  * prevent syslog from deleting initial spaces
177  */
178 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
179 
180 static void print_device_short(device_t dev, int indent);
181 static void print_device(device_t dev, int indent);
182 void print_device_tree_short(device_t dev, int indent);
183 void print_device_tree(device_t dev, int indent);
184 static void print_driver_short(driver_t *driver, int indent);
185 static void print_driver(driver_t *driver, int indent);
186 static void print_driver_list(driver_list_t drivers, int indent);
187 static void print_devclass_short(devclass_t dc, int indent);
188 static void print_devclass(devclass_t dc, int indent);
189 void print_devclass_list_short(void);
190 void print_devclass_list(void);
191 
192 #else
193 /* Make the compiler ignore the function calls */
194 #define PDEBUG(a)			/* nop */
195 #define DEVICENAME(d)			/* nop */
196 
197 #define print_device_short(d,i)		/* nop */
198 #define print_device(d,i)		/* nop */
199 #define print_device_tree_short(d,i)	/* nop */
200 #define print_device_tree(d,i)		/* nop */
201 #define print_driver_short(d,i)		/* nop */
202 #define print_driver(d,i)		/* nop */
203 #define print_driver_list(d,i)		/* nop */
204 #define print_devclass_short(d,i)	/* nop */
205 #define print_devclass(d,i)		/* nop */
206 #define print_devclass_list_short()	/* nop */
207 #define print_devclass_list()		/* nop */
208 #endif
209 
210 /*
211  * dev sysctl tree
212  */
213 
214 enum {
215 	DEVCLASS_SYSCTL_PARENT,
216 };
217 
218 static int
219 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
220 {
221 	devclass_t dc = (devclass_t)arg1;
222 	const char *value;
223 
224 	switch (arg2) {
225 	case DEVCLASS_SYSCTL_PARENT:
226 		value = dc->parent ? dc->parent->name : "";
227 		break;
228 	default:
229 		return (EINVAL);
230 	}
231 	return (SYSCTL_OUT_STR(req, value));
232 }
233 
234 static void
235 devclass_sysctl_init(devclass_t dc)
236 {
237 	if (dc->sysctl_tree != NULL)
238 		return;
239 	sysctl_ctx_init(&dc->sysctl_ctx);
240 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
241 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
242 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
243 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
244 	    OID_AUTO, "%parent",
245 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
246 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
247 	    "parent class");
248 }
249 
250 enum {
251 	DEVICE_SYSCTL_DESC,
252 	DEVICE_SYSCTL_DRIVER,
253 	DEVICE_SYSCTL_LOCATION,
254 	DEVICE_SYSCTL_PNPINFO,
255 	DEVICE_SYSCTL_PARENT,
256 };
257 
258 static int
259 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
260 {
261 	device_t dev = (device_t)arg1;
262 	const char *value;
263 	char *buf;
264 	int error;
265 
266 	buf = NULL;
267 	switch (arg2) {
268 	case DEVICE_SYSCTL_DESC:
269 		value = dev->desc ? dev->desc : "";
270 		break;
271 	case DEVICE_SYSCTL_DRIVER:
272 		value = dev->driver ? dev->driver->name : "";
273 		break;
274 	case DEVICE_SYSCTL_LOCATION:
275 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
276 		bus_child_location_str(dev, buf, 1024);
277 		break;
278 	case DEVICE_SYSCTL_PNPINFO:
279 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
280 		bus_child_pnpinfo_str(dev, buf, 1024);
281 		break;
282 	case DEVICE_SYSCTL_PARENT:
283 		value = dev->parent ? dev->parent->nameunit : "";
284 		break;
285 	default:
286 		return (EINVAL);
287 	}
288 	error = SYSCTL_OUT_STR(req, value);
289 	if (buf != NULL)
290 		free(buf, M_BUS);
291 	return (error);
292 }
293 
294 static void
295 device_sysctl_init(device_t dev)
296 {
297 	devclass_t dc = dev->devclass;
298 	int domain;
299 
300 	if (dev->sysctl_tree != NULL)
301 		return;
302 	devclass_sysctl_init(dc);
303 	sysctl_ctx_init(&dev->sysctl_ctx);
304 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
305 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
306 	    dev->nameunit + strlen(dc->name),
307 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
308 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
309 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
310 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
311 	    "device description");
312 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
313 	    OID_AUTO, "%driver",
314 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
315 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
316 	    "device driver name");
317 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
318 	    OID_AUTO, "%location",
319 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
320 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
321 	    "device location relative to parent");
322 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
323 	    OID_AUTO, "%pnpinfo",
324 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
325 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
326 	    "device identification");
327 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
328 	    OID_AUTO, "%parent",
329 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
330 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
331 	    "parent device");
332 	if (bus_get_domain(dev, &domain) == 0)
333 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
334 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
335 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
336 }
337 
338 static void
339 device_sysctl_update(device_t dev)
340 {
341 	devclass_t dc = dev->devclass;
342 
343 	if (dev->sysctl_tree == NULL)
344 		return;
345 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
346 }
347 
348 static void
349 device_sysctl_fini(device_t dev)
350 {
351 	if (dev->sysctl_tree == NULL)
352 		return;
353 	sysctl_ctx_free(&dev->sysctl_ctx);
354 	dev->sysctl_tree = NULL;
355 }
356 
357 /*
358  * /dev/devctl implementation
359  */
360 
361 /*
362  * This design allows only one reader for /dev/devctl.  This is not desirable
363  * in the long run, but will get a lot of hair out of this implementation.
364  * Maybe we should make this device a clonable device.
365  *
366  * Also note: we specifically do not attach a device to the device_t tree
367  * to avoid potential chicken and egg problems.  One could argue that all
368  * of this belongs to the root node.  One could also further argue that the
369  * sysctl interface that we have not might more properly be an ioctl
370  * interface, but at this stage of the game, I'm not inclined to rock that
371  * boat.
372  *
373  * I'm also not sure that the SIGIO support is done correctly or not, as
374  * I copied it from a driver that had SIGIO support that likely hasn't been
375  * tested since 3.4 or 2.2.8!
376  */
377 
378 /* Deprecated way to adjust queue length */
379 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
380 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RWTUN |
381     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_disable, "I",
382     "devctl disable -- deprecated");
383 
384 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
385 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
386 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
387 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
388     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
389 
390 static d_open_t		devopen;
391 static d_close_t	devclose;
392 static d_read_t		devread;
393 static d_ioctl_t	devioctl;
394 static d_poll_t		devpoll;
395 static d_kqfilter_t	devkqfilter;
396 
397 static struct cdevsw dev_cdevsw = {
398 	.d_version =	D_VERSION,
399 	.d_open =	devopen,
400 	.d_close =	devclose,
401 	.d_read =	devread,
402 	.d_ioctl =	devioctl,
403 	.d_poll =	devpoll,
404 	.d_kqfilter =	devkqfilter,
405 	.d_name =	"devctl",
406 };
407 
408 struct dev_event_info
409 {
410 	char *dei_data;
411 	TAILQ_ENTRY(dev_event_info) dei_link;
412 };
413 
414 TAILQ_HEAD(devq, dev_event_info);
415 
416 static struct dev_softc
417 {
418 	int	inuse;
419 	int	nonblock;
420 	int	queued;
421 	int	async;
422 	struct mtx mtx;
423 	struct cv cv;
424 	struct selinfo sel;
425 	struct devq devq;
426 	struct sigio *sigio;
427 } devsoftc;
428 
429 static void	filt_devctl_detach(struct knote *kn);
430 static int	filt_devctl_read(struct knote *kn, long hint);
431 
432 struct filterops devctl_rfiltops = {
433 	.f_isfd = 1,
434 	.f_detach = filt_devctl_detach,
435 	.f_event = filt_devctl_read,
436 };
437 
438 static struct cdev *devctl_dev;
439 
440 static void
441 devinit(void)
442 {
443 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
444 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
445 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
446 	cv_init(&devsoftc.cv, "dev cv");
447 	TAILQ_INIT(&devsoftc.devq);
448 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
449 	devctl2_init();
450 }
451 
452 static int
453 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
454 {
455 	mtx_lock(&devsoftc.mtx);
456 	if (devsoftc.inuse) {
457 		mtx_unlock(&devsoftc.mtx);
458 		return (EBUSY);
459 	}
460 	/* move to init */
461 	devsoftc.inuse = 1;
462 	mtx_unlock(&devsoftc.mtx);
463 	return (0);
464 }
465 
466 static int
467 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
468 {
469 	mtx_lock(&devsoftc.mtx);
470 	devsoftc.inuse = 0;
471 	devsoftc.nonblock = 0;
472 	devsoftc.async = 0;
473 	cv_broadcast(&devsoftc.cv);
474 	funsetown(&devsoftc.sigio);
475 	mtx_unlock(&devsoftc.mtx);
476 	return (0);
477 }
478 
479 /*
480  * The read channel for this device is used to report changes to
481  * userland in realtime.  We are required to free the data as well as
482  * the n1 object because we allocate them separately.  Also note that
483  * we return one record at a time.  If you try to read this device a
484  * character at a time, you will lose the rest of the data.  Listening
485  * programs are expected to cope.
486  */
487 static int
488 devread(struct cdev *dev, struct uio *uio, int ioflag)
489 {
490 	struct dev_event_info *n1;
491 	int rv;
492 
493 	mtx_lock(&devsoftc.mtx);
494 	while (TAILQ_EMPTY(&devsoftc.devq)) {
495 		if (devsoftc.nonblock) {
496 			mtx_unlock(&devsoftc.mtx);
497 			return (EAGAIN);
498 		}
499 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
500 		if (rv) {
501 			/*
502 			 * Need to translate ERESTART to EINTR here? -- jake
503 			 */
504 			mtx_unlock(&devsoftc.mtx);
505 			return (rv);
506 		}
507 	}
508 	n1 = TAILQ_FIRST(&devsoftc.devq);
509 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
510 	devsoftc.queued--;
511 	mtx_unlock(&devsoftc.mtx);
512 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
513 	free(n1->dei_data, M_BUS);
514 	free(n1, M_BUS);
515 	return (rv);
516 }
517 
518 static	int
519 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
520 {
521 	switch (cmd) {
522 	case FIONBIO:
523 		if (*(int*)data)
524 			devsoftc.nonblock = 1;
525 		else
526 			devsoftc.nonblock = 0;
527 		return (0);
528 	case FIOASYNC:
529 		if (*(int*)data)
530 			devsoftc.async = 1;
531 		else
532 			devsoftc.async = 0;
533 		return (0);
534 	case FIOSETOWN:
535 		return fsetown(*(int *)data, &devsoftc.sigio);
536 	case FIOGETOWN:
537 		*(int *)data = fgetown(&devsoftc.sigio);
538 		return (0);
539 
540 		/* (un)Support for other fcntl() calls. */
541 	case FIOCLEX:
542 	case FIONCLEX:
543 	case FIONREAD:
544 	default:
545 		break;
546 	}
547 	return (ENOTTY);
548 }
549 
550 static	int
551 devpoll(struct cdev *dev, int events, struct thread *td)
552 {
553 	int	revents = 0;
554 
555 	mtx_lock(&devsoftc.mtx);
556 	if (events & (POLLIN | POLLRDNORM)) {
557 		if (!TAILQ_EMPTY(&devsoftc.devq))
558 			revents = events & (POLLIN | POLLRDNORM);
559 		else
560 			selrecord(td, &devsoftc.sel);
561 	}
562 	mtx_unlock(&devsoftc.mtx);
563 
564 	return (revents);
565 }
566 
567 static int
568 devkqfilter(struct cdev *dev, struct knote *kn)
569 {
570 	int error;
571 
572 	if (kn->kn_filter == EVFILT_READ) {
573 		kn->kn_fop = &devctl_rfiltops;
574 		knlist_add(&devsoftc.sel.si_note, kn, 0);
575 		error = 0;
576 	} else
577 		error = EINVAL;
578 	return (error);
579 }
580 
581 static void
582 filt_devctl_detach(struct knote *kn)
583 {
584 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
585 }
586 
587 static int
588 filt_devctl_read(struct knote *kn, long hint)
589 {
590 	kn->kn_data = devsoftc.queued;
591 	return (kn->kn_data != 0);
592 }
593 
594 /**
595  * @brief Return whether the userland process is running
596  */
597 boolean_t
598 devctl_process_running(void)
599 {
600 	return (devsoftc.inuse == 1);
601 }
602 
603 /**
604  * @brief Queue data to be read from the devctl device
605  *
606  * Generic interface to queue data to the devctl device.  It is
607  * assumed that @p data is properly formatted.  It is further assumed
608  * that @p data is allocated using the M_BUS malloc type.
609  */
610 void
611 devctl_queue_data_f(char *data, int flags)
612 {
613 	struct dev_event_info *n1 = NULL, *n2 = NULL;
614 
615 	if (strlen(data) == 0)
616 		goto out;
617 	if (devctl_queue_length == 0)
618 		goto out;
619 	n1 = malloc(sizeof(*n1), M_BUS, flags);
620 	if (n1 == NULL)
621 		goto out;
622 	n1->dei_data = data;
623 	mtx_lock(&devsoftc.mtx);
624 	if (devctl_queue_length == 0) {
625 		mtx_unlock(&devsoftc.mtx);
626 		free(n1->dei_data, M_BUS);
627 		free(n1, M_BUS);
628 		return;
629 	}
630 	/* Leave at least one spot in the queue... */
631 	while (devsoftc.queued > devctl_queue_length - 1) {
632 		n2 = TAILQ_FIRST(&devsoftc.devq);
633 		TAILQ_REMOVE(&devsoftc.devq, n2, dei_link);
634 		free(n2->dei_data, M_BUS);
635 		free(n2, M_BUS);
636 		devsoftc.queued--;
637 	}
638 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
639 	devsoftc.queued++;
640 	cv_broadcast(&devsoftc.cv);
641 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
642 	mtx_unlock(&devsoftc.mtx);
643 	selwakeup(&devsoftc.sel);
644 	if (devsoftc.async && devsoftc.sigio != NULL)
645 		pgsigio(&devsoftc.sigio, SIGIO, 0);
646 	return;
647 out:
648 	/*
649 	 * We have to free data on all error paths since the caller
650 	 * assumes it will be free'd when this item is dequeued.
651 	 */
652 	free(data, M_BUS);
653 	return;
654 }
655 
656 void
657 devctl_queue_data(char *data)
658 {
659 	devctl_queue_data_f(data, M_NOWAIT);
660 }
661 
662 /**
663  * @brief Send a 'notification' to userland, using standard ways
664  */
665 void
666 devctl_notify_f(const char *system, const char *subsystem, const char *type,
667     const char *data, int flags)
668 {
669 	int len = 0;
670 	char *msg;
671 
672 	if (system == NULL)
673 		return;		/* BOGUS!  Must specify system. */
674 	if (subsystem == NULL)
675 		return;		/* BOGUS!  Must specify subsystem. */
676 	if (type == NULL)
677 		return;		/* BOGUS!  Must specify type. */
678 	len += strlen(" system=") + strlen(system);
679 	len += strlen(" subsystem=") + strlen(subsystem);
680 	len += strlen(" type=") + strlen(type);
681 	/* add in the data message plus newline. */
682 	if (data != NULL)
683 		len += strlen(data);
684 	len += 3;	/* '!', '\n', and NUL */
685 	msg = malloc(len, M_BUS, flags);
686 	if (msg == NULL)
687 		return;		/* Drop it on the floor */
688 	if (data != NULL)
689 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
690 		    system, subsystem, type, data);
691 	else
692 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
693 		    system, subsystem, type);
694 	devctl_queue_data_f(msg, flags);
695 }
696 
697 void
698 devctl_notify(const char *system, const char *subsystem, const char *type,
699     const char *data)
700 {
701 	devctl_notify_f(system, subsystem, type, data, M_NOWAIT);
702 }
703 
704 /*
705  * Common routine that tries to make sending messages as easy as possible.
706  * We allocate memory for the data, copy strings into that, but do not
707  * free it unless there's an error.  The dequeue part of the driver should
708  * free the data.  We don't send data when the device is disabled.  We do
709  * send data, even when we have no listeners, because we wish to avoid
710  * races relating to startup and restart of listening applications.
711  *
712  * devaddq is designed to string together the type of event, with the
713  * object of that event, plus the plug and play info and location info
714  * for that event.  This is likely most useful for devices, but less
715  * useful for other consumers of this interface.  Those should use
716  * the devctl_queue_data() interface instead.
717  */
718 static void
719 devaddq(const char *type, const char *what, device_t dev)
720 {
721 	char *data = NULL;
722 	char *loc = NULL;
723 	char *pnp = NULL;
724 	const char *parstr;
725 
726 	if (!devctl_queue_length)/* Rare race, but lost races safely discard */
727 		return;
728 	data = malloc(1024, M_BUS, M_NOWAIT);
729 	if (data == NULL)
730 		goto bad;
731 
732 	/* get the bus specific location of this device */
733 	loc = malloc(1024, M_BUS, M_NOWAIT);
734 	if (loc == NULL)
735 		goto bad;
736 	*loc = '\0';
737 	bus_child_location_str(dev, loc, 1024);
738 
739 	/* Get the bus specific pnp info of this device */
740 	pnp = malloc(1024, M_BUS, M_NOWAIT);
741 	if (pnp == NULL)
742 		goto bad;
743 	*pnp = '\0';
744 	bus_child_pnpinfo_str(dev, pnp, 1024);
745 
746 	/* Get the parent of this device, or / if high enough in the tree. */
747 	if (device_get_parent(dev) == NULL)
748 		parstr = ".";	/* Or '/' ? */
749 	else
750 		parstr = device_get_nameunit(device_get_parent(dev));
751 	/* String it all together. */
752 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
753 	  parstr);
754 	free(loc, M_BUS);
755 	free(pnp, M_BUS);
756 	devctl_queue_data(data);
757 	return;
758 bad:
759 	free(pnp, M_BUS);
760 	free(loc, M_BUS);
761 	free(data, M_BUS);
762 	return;
763 }
764 
765 /*
766  * A device was added to the tree.  We are called just after it successfully
767  * attaches (that is, probe and attach success for this device).  No call
768  * is made if a device is merely parented into the tree.  See devnomatch
769  * if probe fails.  If attach fails, no notification is sent (but maybe
770  * we should have a different message for this).
771  */
772 static void
773 devadded(device_t dev)
774 {
775 	devaddq("+", device_get_nameunit(dev), dev);
776 }
777 
778 /*
779  * A device was removed from the tree.  We are called just before this
780  * happens.
781  */
782 static void
783 devremoved(device_t dev)
784 {
785 	devaddq("-", device_get_nameunit(dev), dev);
786 }
787 
788 /*
789  * Called when there's no match for this device.  This is only called
790  * the first time that no match happens, so we don't keep getting this
791  * message.  Should that prove to be undesirable, we can change it.
792  * This is called when all drivers that can attach to a given bus
793  * decline to accept this device.  Other errors may not be detected.
794  */
795 static void
796 devnomatch(device_t dev)
797 {
798 	devaddq("?", "", dev);
799 }
800 
801 static int
802 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
803 {
804 	struct dev_event_info *n1;
805 	int dis, error;
806 
807 	dis = (devctl_queue_length == 0);
808 	error = sysctl_handle_int(oidp, &dis, 0, req);
809 	if (error || !req->newptr)
810 		return (error);
811 	if (mtx_initialized(&devsoftc.mtx))
812 		mtx_lock(&devsoftc.mtx);
813 	if (dis) {
814 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
815 			n1 = TAILQ_FIRST(&devsoftc.devq);
816 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
817 			free(n1->dei_data, M_BUS);
818 			free(n1, M_BUS);
819 		}
820 		devsoftc.queued = 0;
821 		devctl_queue_length = 0;
822 	} else {
823 		devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
824 	}
825 	if (mtx_initialized(&devsoftc.mtx))
826 		mtx_unlock(&devsoftc.mtx);
827 	return (0);
828 }
829 
830 static int
831 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
832 {
833 	struct dev_event_info *n1;
834 	int q, error;
835 
836 	q = devctl_queue_length;
837 	error = sysctl_handle_int(oidp, &q, 0, req);
838 	if (error || !req->newptr)
839 		return (error);
840 	if (q < 0)
841 		return (EINVAL);
842 	if (mtx_initialized(&devsoftc.mtx))
843 		mtx_lock(&devsoftc.mtx);
844 	devctl_queue_length = q;
845 	while (devsoftc.queued > devctl_queue_length) {
846 		n1 = TAILQ_FIRST(&devsoftc.devq);
847 		TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
848 		free(n1->dei_data, M_BUS);
849 		free(n1, M_BUS);
850 		devsoftc.queued--;
851 	}
852 	if (mtx_initialized(&devsoftc.mtx))
853 		mtx_unlock(&devsoftc.mtx);
854 	return (0);
855 }
856 
857 /**
858  * @brief safely quotes strings that might have double quotes in them.
859  *
860  * The devctl protocol relies on quoted strings having matching quotes.
861  * This routine quotes any internal quotes so the resulting string
862  * is safe to pass to snprintf to construct, for example pnp info strings.
863  * Strings are always terminated with a NUL, but may be truncated if longer
864  * than @p len bytes after quotes.
865  *
866  * @param sb	sbuf to place the characters into
867  * @param src	Original buffer.
868  */
869 void
870 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
871 {
872 	while (*src != '\0') {
873 		if (*src == '"' || *src == '\\')
874 			sbuf_putc(sb, '\\');
875 		sbuf_putc(sb, *src++);
876 	}
877 }
878 
879 /* End of /dev/devctl code */
880 
881 static TAILQ_HEAD(,device)	bus_data_devices;
882 static int bus_data_generation = 1;
883 
884 static kobj_method_t null_methods[] = {
885 	KOBJMETHOD_END
886 };
887 
888 DEFINE_CLASS(null, null_methods, 0);
889 
890 /*
891  * Bus pass implementation
892  */
893 
894 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
895 int bus_current_pass = BUS_PASS_ROOT;
896 
897 /**
898  * @internal
899  * @brief Register the pass level of a new driver attachment
900  *
901  * Register a new driver attachment's pass level.  If no driver
902  * attachment with the same pass level has been added, then @p new
903  * will be added to the global passes list.
904  *
905  * @param new		the new driver attachment
906  */
907 static void
908 driver_register_pass(struct driverlink *new)
909 {
910 	struct driverlink *dl;
911 
912 	/* We only consider pass numbers during boot. */
913 	if (bus_current_pass == BUS_PASS_DEFAULT)
914 		return;
915 
916 	/*
917 	 * Walk the passes list.  If we already know about this pass
918 	 * then there is nothing to do.  If we don't, then insert this
919 	 * driver link into the list.
920 	 */
921 	TAILQ_FOREACH(dl, &passes, passlink) {
922 		if (dl->pass < new->pass)
923 			continue;
924 		if (dl->pass == new->pass)
925 			return;
926 		TAILQ_INSERT_BEFORE(dl, new, passlink);
927 		return;
928 	}
929 	TAILQ_INSERT_TAIL(&passes, new, passlink);
930 }
931 
932 /**
933  * @brief Raise the current bus pass
934  *
935  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
936  * method on the root bus to kick off a new device tree scan for each
937  * new pass level that has at least one driver.
938  */
939 void
940 bus_set_pass(int pass)
941 {
942 	struct driverlink *dl;
943 
944 	if (bus_current_pass > pass)
945 		panic("Attempt to lower bus pass level");
946 
947 	TAILQ_FOREACH(dl, &passes, passlink) {
948 		/* Skip pass values below the current pass level. */
949 		if (dl->pass <= bus_current_pass)
950 			continue;
951 
952 		/*
953 		 * Bail once we hit a driver with a pass level that is
954 		 * too high.
955 		 */
956 		if (dl->pass > pass)
957 			break;
958 
959 		/*
960 		 * Raise the pass level to the next level and rescan
961 		 * the tree.
962 		 */
963 		bus_current_pass = dl->pass;
964 		BUS_NEW_PASS(root_bus);
965 	}
966 
967 	/*
968 	 * If there isn't a driver registered for the requested pass,
969 	 * then bus_current_pass might still be less than 'pass'.  Set
970 	 * it to 'pass' in that case.
971 	 */
972 	if (bus_current_pass < pass)
973 		bus_current_pass = pass;
974 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
975 }
976 
977 /*
978  * Devclass implementation
979  */
980 
981 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
982 
983 /**
984  * @internal
985  * @brief Find or create a device class
986  *
987  * If a device class with the name @p classname exists, return it,
988  * otherwise if @p create is non-zero create and return a new device
989  * class.
990  *
991  * If @p parentname is non-NULL, the parent of the devclass is set to
992  * the devclass of that name.
993  *
994  * @param classname	the devclass name to find or create
995  * @param parentname	the parent devclass name or @c NULL
996  * @param create	non-zero to create a devclass
997  */
998 static devclass_t
999 devclass_find_internal(const char *classname, const char *parentname,
1000 		       int create)
1001 {
1002 	devclass_t dc;
1003 
1004 	PDEBUG(("looking for %s", classname));
1005 	if (!classname)
1006 		return (NULL);
1007 
1008 	TAILQ_FOREACH(dc, &devclasses, link) {
1009 		if (!strcmp(dc->name, classname))
1010 			break;
1011 	}
1012 
1013 	if (create && !dc) {
1014 		PDEBUG(("creating %s", classname));
1015 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1016 		    M_BUS, M_NOWAIT | M_ZERO);
1017 		if (!dc)
1018 			return (NULL);
1019 		dc->parent = NULL;
1020 		dc->name = (char*) (dc + 1);
1021 		strcpy(dc->name, classname);
1022 		TAILQ_INIT(&dc->drivers);
1023 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1024 
1025 		bus_data_generation_update();
1026 	}
1027 
1028 	/*
1029 	 * If a parent class is specified, then set that as our parent so
1030 	 * that this devclass will support drivers for the parent class as
1031 	 * well.  If the parent class has the same name don't do this though
1032 	 * as it creates a cycle that can trigger an infinite loop in
1033 	 * device_probe_child() if a device exists for which there is no
1034 	 * suitable driver.
1035 	 */
1036 	if (parentname && dc && !dc->parent &&
1037 	    strcmp(classname, parentname) != 0) {
1038 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1039 		dc->parent->flags |= DC_HAS_CHILDREN;
1040 	}
1041 
1042 	return (dc);
1043 }
1044 
1045 /**
1046  * @brief Create a device class
1047  *
1048  * If a device class with the name @p classname exists, return it,
1049  * otherwise create and return a new device class.
1050  *
1051  * @param classname	the devclass name to find or create
1052  */
1053 devclass_t
1054 devclass_create(const char *classname)
1055 {
1056 	return (devclass_find_internal(classname, NULL, TRUE));
1057 }
1058 
1059 /**
1060  * @brief Find a device class
1061  *
1062  * If a device class with the name @p classname exists, return it,
1063  * otherwise return @c NULL.
1064  *
1065  * @param classname	the devclass name to find
1066  */
1067 devclass_t
1068 devclass_find(const char *classname)
1069 {
1070 	return (devclass_find_internal(classname, NULL, FALSE));
1071 }
1072 
1073 /**
1074  * @brief Register that a device driver has been added to a devclass
1075  *
1076  * Register that a device driver has been added to a devclass.  This
1077  * is called by devclass_add_driver to accomplish the recursive
1078  * notification of all the children classes of dc, as well as dc.
1079  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1080  * the devclass.
1081  *
1082  * We do a full search here of the devclass list at each iteration
1083  * level to save storing children-lists in the devclass structure.  If
1084  * we ever move beyond a few dozen devices doing this, we may need to
1085  * reevaluate...
1086  *
1087  * @param dc		the devclass to edit
1088  * @param driver	the driver that was just added
1089  */
1090 static void
1091 devclass_driver_added(devclass_t dc, driver_t *driver)
1092 {
1093 	devclass_t parent;
1094 	int i;
1095 
1096 	/*
1097 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1098 	 */
1099 	for (i = 0; i < dc->maxunit; i++)
1100 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1101 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1102 
1103 	/*
1104 	 * Walk through the children classes.  Since we only keep a
1105 	 * single parent pointer around, we walk the entire list of
1106 	 * devclasses looking for children.  We set the
1107 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1108 	 * the parent, so we only walk the list for those devclasses
1109 	 * that have children.
1110 	 */
1111 	if (!(dc->flags & DC_HAS_CHILDREN))
1112 		return;
1113 	parent = dc;
1114 	TAILQ_FOREACH(dc, &devclasses, link) {
1115 		if (dc->parent == parent)
1116 			devclass_driver_added(dc, driver);
1117 	}
1118 }
1119 
1120 /**
1121  * @brief Add a device driver to a device class
1122  *
1123  * Add a device driver to a devclass. This is normally called
1124  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1125  * all devices in the devclass will be called to allow them to attempt
1126  * to re-probe any unmatched children.
1127  *
1128  * @param dc		the devclass to edit
1129  * @param driver	the driver to register
1130  */
1131 int
1132 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1133 {
1134 	driverlink_t dl;
1135 	const char *parentname;
1136 
1137 	PDEBUG(("%s", DRIVERNAME(driver)));
1138 
1139 	/* Don't allow invalid pass values. */
1140 	if (pass <= BUS_PASS_ROOT)
1141 		return (EINVAL);
1142 
1143 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1144 	if (!dl)
1145 		return (ENOMEM);
1146 
1147 	/*
1148 	 * Compile the driver's methods. Also increase the reference count
1149 	 * so that the class doesn't get freed when the last instance
1150 	 * goes. This means we can safely use static methods and avoids a
1151 	 * double-free in devclass_delete_driver.
1152 	 */
1153 	kobj_class_compile((kobj_class_t) driver);
1154 
1155 	/*
1156 	 * If the driver has any base classes, make the
1157 	 * devclass inherit from the devclass of the driver's
1158 	 * first base class. This will allow the system to
1159 	 * search for drivers in both devclasses for children
1160 	 * of a device using this driver.
1161 	 */
1162 	if (driver->baseclasses)
1163 		parentname = driver->baseclasses[0]->name;
1164 	else
1165 		parentname = NULL;
1166 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1167 
1168 	dl->driver = driver;
1169 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1170 	driver->refs++;		/* XXX: kobj_mtx */
1171 	dl->pass = pass;
1172 	driver_register_pass(dl);
1173 
1174 	if (device_frozen) {
1175 		dl->flags |= DL_DEFERRED_PROBE;
1176 	} else {
1177 		devclass_driver_added(dc, driver);
1178 	}
1179 	bus_data_generation_update();
1180 	return (0);
1181 }
1182 
1183 /**
1184  * @brief Register that a device driver has been deleted from a devclass
1185  *
1186  * Register that a device driver has been removed from a devclass.
1187  * This is called by devclass_delete_driver to accomplish the
1188  * recursive notification of all the children classes of busclass, as
1189  * well as busclass.  Each layer will attempt to detach the driver
1190  * from any devices that are children of the bus's devclass.  The function
1191  * will return an error if a device fails to detach.
1192  *
1193  * We do a full search here of the devclass list at each iteration
1194  * level to save storing children-lists in the devclass structure.  If
1195  * we ever move beyond a few dozen devices doing this, we may need to
1196  * reevaluate...
1197  *
1198  * @param busclass	the devclass of the parent bus
1199  * @param dc		the devclass of the driver being deleted
1200  * @param driver	the driver being deleted
1201  */
1202 static int
1203 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1204 {
1205 	devclass_t parent;
1206 	device_t dev;
1207 	int error, i;
1208 
1209 	/*
1210 	 * Disassociate from any devices.  We iterate through all the
1211 	 * devices in the devclass of the driver and detach any which are
1212 	 * using the driver and which have a parent in the devclass which
1213 	 * we are deleting from.
1214 	 *
1215 	 * Note that since a driver can be in multiple devclasses, we
1216 	 * should not detach devices which are not children of devices in
1217 	 * the affected devclass.
1218 	 *
1219 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1220 	 * generate later.
1221 	 */
1222 	for (i = 0; i < dc->maxunit; i++) {
1223 		if (dc->devices[i]) {
1224 			dev = dc->devices[i];
1225 			if (dev->driver == driver && dev->parent &&
1226 			    dev->parent->devclass == busclass) {
1227 				if ((error = device_detach(dev)) != 0)
1228 					return (error);
1229 				if (device_frozen) {
1230 					dev->flags &= ~DF_DONENOMATCH;
1231 					dev->flags |= DF_NEEDNOMATCH;
1232 				} else {
1233 					BUS_PROBE_NOMATCH(dev->parent, dev);
1234 					devnomatch(dev);
1235 					dev->flags |= DF_DONENOMATCH;
1236 				}
1237 			}
1238 		}
1239 	}
1240 
1241 	/*
1242 	 * Walk through the children classes.  Since we only keep a
1243 	 * single parent pointer around, we walk the entire list of
1244 	 * devclasses looking for children.  We set the
1245 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1246 	 * the parent, so we only walk the list for those devclasses
1247 	 * that have children.
1248 	 */
1249 	if (!(busclass->flags & DC_HAS_CHILDREN))
1250 		return (0);
1251 	parent = busclass;
1252 	TAILQ_FOREACH(busclass, &devclasses, link) {
1253 		if (busclass->parent == parent) {
1254 			error = devclass_driver_deleted(busclass, dc, driver);
1255 			if (error)
1256 				return (error);
1257 		}
1258 	}
1259 	return (0);
1260 }
1261 
1262 /**
1263  * @brief Delete a device driver from a device class
1264  *
1265  * Delete a device driver from a devclass. This is normally called
1266  * automatically by DRIVER_MODULE().
1267  *
1268  * If the driver is currently attached to any devices,
1269  * devclass_delete_driver() will first attempt to detach from each
1270  * device. If one of the detach calls fails, the driver will not be
1271  * deleted.
1272  *
1273  * @param dc		the devclass to edit
1274  * @param driver	the driver to unregister
1275  */
1276 int
1277 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1278 {
1279 	devclass_t dc = devclass_find(driver->name);
1280 	driverlink_t dl;
1281 	int error;
1282 
1283 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1284 
1285 	if (!dc)
1286 		return (0);
1287 
1288 	/*
1289 	 * Find the link structure in the bus' list of drivers.
1290 	 */
1291 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1292 		if (dl->driver == driver)
1293 			break;
1294 	}
1295 
1296 	if (!dl) {
1297 		PDEBUG(("%s not found in %s list", driver->name,
1298 		    busclass->name));
1299 		return (ENOENT);
1300 	}
1301 
1302 	error = devclass_driver_deleted(busclass, dc, driver);
1303 	if (error != 0)
1304 		return (error);
1305 
1306 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1307 	free(dl, M_BUS);
1308 
1309 	/* XXX: kobj_mtx */
1310 	driver->refs--;
1311 	if (driver->refs == 0)
1312 		kobj_class_free((kobj_class_t) driver);
1313 
1314 	bus_data_generation_update();
1315 	return (0);
1316 }
1317 
1318 /**
1319  * @brief Quiesces a set of device drivers from a device class
1320  *
1321  * Quiesce a device driver from a devclass. This is normally called
1322  * automatically by DRIVER_MODULE().
1323  *
1324  * If the driver is currently attached to any devices,
1325  * devclass_quiesece_driver() will first attempt to quiesce each
1326  * device.
1327  *
1328  * @param dc		the devclass to edit
1329  * @param driver	the driver to unregister
1330  */
1331 static int
1332 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1333 {
1334 	devclass_t dc = devclass_find(driver->name);
1335 	driverlink_t dl;
1336 	device_t dev;
1337 	int i;
1338 	int error;
1339 
1340 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1341 
1342 	if (!dc)
1343 		return (0);
1344 
1345 	/*
1346 	 * Find the link structure in the bus' list of drivers.
1347 	 */
1348 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1349 		if (dl->driver == driver)
1350 			break;
1351 	}
1352 
1353 	if (!dl) {
1354 		PDEBUG(("%s not found in %s list", driver->name,
1355 		    busclass->name));
1356 		return (ENOENT);
1357 	}
1358 
1359 	/*
1360 	 * Quiesce all devices.  We iterate through all the devices in
1361 	 * the devclass of the driver and quiesce any which are using
1362 	 * the driver and which have a parent in the devclass which we
1363 	 * are quiescing.
1364 	 *
1365 	 * Note that since a driver can be in multiple devclasses, we
1366 	 * should not quiesce devices which are not children of
1367 	 * devices in the affected devclass.
1368 	 */
1369 	for (i = 0; i < dc->maxunit; i++) {
1370 		if (dc->devices[i]) {
1371 			dev = dc->devices[i];
1372 			if (dev->driver == driver && dev->parent &&
1373 			    dev->parent->devclass == busclass) {
1374 				if ((error = device_quiesce(dev)) != 0)
1375 					return (error);
1376 			}
1377 		}
1378 	}
1379 
1380 	return (0);
1381 }
1382 
1383 /**
1384  * @internal
1385  */
1386 static driverlink_t
1387 devclass_find_driver_internal(devclass_t dc, const char *classname)
1388 {
1389 	driverlink_t dl;
1390 
1391 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1392 
1393 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1394 		if (!strcmp(dl->driver->name, classname))
1395 			return (dl);
1396 	}
1397 
1398 	PDEBUG(("not found"));
1399 	return (NULL);
1400 }
1401 
1402 /**
1403  * @brief Return the name of the devclass
1404  */
1405 const char *
1406 devclass_get_name(devclass_t dc)
1407 {
1408 	return (dc->name);
1409 }
1410 
1411 /**
1412  * @brief Find a device given a unit number
1413  *
1414  * @param dc		the devclass to search
1415  * @param unit		the unit number to search for
1416  *
1417  * @returns		the device with the given unit number or @c
1418  *			NULL if there is no such device
1419  */
1420 device_t
1421 devclass_get_device(devclass_t dc, int unit)
1422 {
1423 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1424 		return (NULL);
1425 	return (dc->devices[unit]);
1426 }
1427 
1428 /**
1429  * @brief Find the softc field of a device given a unit number
1430  *
1431  * @param dc		the devclass to search
1432  * @param unit		the unit number to search for
1433  *
1434  * @returns		the softc field of the device with the given
1435  *			unit number or @c NULL if there is no such
1436  *			device
1437  */
1438 void *
1439 devclass_get_softc(devclass_t dc, int unit)
1440 {
1441 	device_t dev;
1442 
1443 	dev = devclass_get_device(dc, unit);
1444 	if (!dev)
1445 		return (NULL);
1446 
1447 	return (device_get_softc(dev));
1448 }
1449 
1450 /**
1451  * @brief Get a list of devices in the devclass
1452  *
1453  * An array containing a list of all the devices in the given devclass
1454  * is allocated and returned in @p *devlistp. The number of devices
1455  * in the array is returned in @p *devcountp. The caller should free
1456  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1457  *
1458  * @param dc		the devclass to examine
1459  * @param devlistp	points at location for array pointer return
1460  *			value
1461  * @param devcountp	points at location for array size return value
1462  *
1463  * @retval 0		success
1464  * @retval ENOMEM	the array allocation failed
1465  */
1466 int
1467 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1468 {
1469 	int count, i;
1470 	device_t *list;
1471 
1472 	count = devclass_get_count(dc);
1473 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1474 	if (!list)
1475 		return (ENOMEM);
1476 
1477 	count = 0;
1478 	for (i = 0; i < dc->maxunit; i++) {
1479 		if (dc->devices[i]) {
1480 			list[count] = dc->devices[i];
1481 			count++;
1482 		}
1483 	}
1484 
1485 	*devlistp = list;
1486 	*devcountp = count;
1487 
1488 	return (0);
1489 }
1490 
1491 /**
1492  * @brief Get a list of drivers in the devclass
1493  *
1494  * An array containing a list of pointers to all the drivers in the
1495  * given devclass is allocated and returned in @p *listp.  The number
1496  * of drivers in the array is returned in @p *countp. The caller should
1497  * free the array using @c free(p, M_TEMP).
1498  *
1499  * @param dc		the devclass to examine
1500  * @param listp		gives location for array pointer return value
1501  * @param countp	gives location for number of array elements
1502  *			return value
1503  *
1504  * @retval 0		success
1505  * @retval ENOMEM	the array allocation failed
1506  */
1507 int
1508 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1509 {
1510 	driverlink_t dl;
1511 	driver_t **list;
1512 	int count;
1513 
1514 	count = 0;
1515 	TAILQ_FOREACH(dl, &dc->drivers, link)
1516 		count++;
1517 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1518 	if (list == NULL)
1519 		return (ENOMEM);
1520 
1521 	count = 0;
1522 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1523 		list[count] = dl->driver;
1524 		count++;
1525 	}
1526 	*listp = list;
1527 	*countp = count;
1528 
1529 	return (0);
1530 }
1531 
1532 /**
1533  * @brief Get the number of devices in a devclass
1534  *
1535  * @param dc		the devclass to examine
1536  */
1537 int
1538 devclass_get_count(devclass_t dc)
1539 {
1540 	int count, i;
1541 
1542 	count = 0;
1543 	for (i = 0; i < dc->maxunit; i++)
1544 		if (dc->devices[i])
1545 			count++;
1546 	return (count);
1547 }
1548 
1549 /**
1550  * @brief Get the maximum unit number used in a devclass
1551  *
1552  * Note that this is one greater than the highest currently-allocated
1553  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1554  * that not even the devclass has been allocated yet.
1555  *
1556  * @param dc		the devclass to examine
1557  */
1558 int
1559 devclass_get_maxunit(devclass_t dc)
1560 {
1561 	if (dc == NULL)
1562 		return (-1);
1563 	return (dc->maxunit);
1564 }
1565 
1566 /**
1567  * @brief Find a free unit number in a devclass
1568  *
1569  * This function searches for the first unused unit number greater
1570  * that or equal to @p unit.
1571  *
1572  * @param dc		the devclass to examine
1573  * @param unit		the first unit number to check
1574  */
1575 int
1576 devclass_find_free_unit(devclass_t dc, int unit)
1577 {
1578 	if (dc == NULL)
1579 		return (unit);
1580 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1581 		unit++;
1582 	return (unit);
1583 }
1584 
1585 /**
1586  * @brief Set the parent of a devclass
1587  *
1588  * The parent class is normally initialised automatically by
1589  * DRIVER_MODULE().
1590  *
1591  * @param dc		the devclass to edit
1592  * @param pdc		the new parent devclass
1593  */
1594 void
1595 devclass_set_parent(devclass_t dc, devclass_t pdc)
1596 {
1597 	dc->parent = pdc;
1598 }
1599 
1600 /**
1601  * @brief Get the parent of a devclass
1602  *
1603  * @param dc		the devclass to examine
1604  */
1605 devclass_t
1606 devclass_get_parent(devclass_t dc)
1607 {
1608 	return (dc->parent);
1609 }
1610 
1611 struct sysctl_ctx_list *
1612 devclass_get_sysctl_ctx(devclass_t dc)
1613 {
1614 	return (&dc->sysctl_ctx);
1615 }
1616 
1617 struct sysctl_oid *
1618 devclass_get_sysctl_tree(devclass_t dc)
1619 {
1620 	return (dc->sysctl_tree);
1621 }
1622 
1623 /**
1624  * @internal
1625  * @brief Allocate a unit number
1626  *
1627  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1628  * will do). The allocated unit number is returned in @p *unitp.
1629 
1630  * @param dc		the devclass to allocate from
1631  * @param unitp		points at the location for the allocated unit
1632  *			number
1633  *
1634  * @retval 0		success
1635  * @retval EEXIST	the requested unit number is already allocated
1636  * @retval ENOMEM	memory allocation failure
1637  */
1638 static int
1639 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1640 {
1641 	const char *s;
1642 	int unit = *unitp;
1643 
1644 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1645 
1646 	/* Ask the parent bus if it wants to wire this device. */
1647 	if (unit == -1)
1648 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1649 		    &unit);
1650 
1651 	/* If we were given a wired unit number, check for existing device */
1652 	/* XXX imp XXX */
1653 	if (unit != -1) {
1654 		if (unit >= 0 && unit < dc->maxunit &&
1655 		    dc->devices[unit] != NULL) {
1656 			if (bootverbose)
1657 				printf("%s: %s%d already exists; skipping it\n",
1658 				    dc->name, dc->name, *unitp);
1659 			return (EEXIST);
1660 		}
1661 	} else {
1662 		/* Unwired device, find the next available slot for it */
1663 		unit = 0;
1664 		for (unit = 0;; unit++) {
1665 			/* If there is an "at" hint for a unit then skip it. */
1666 			if (resource_string_value(dc->name, unit, "at", &s) ==
1667 			    0)
1668 				continue;
1669 
1670 			/* If this device slot is already in use, skip it. */
1671 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1672 				continue;
1673 
1674 			break;
1675 		}
1676 	}
1677 
1678 	/*
1679 	 * We've selected a unit beyond the length of the table, so let's
1680 	 * extend the table to make room for all units up to and including
1681 	 * this one.
1682 	 */
1683 	if (unit >= dc->maxunit) {
1684 		device_t *newlist, *oldlist;
1685 		int newsize;
1686 
1687 		oldlist = dc->devices;
1688 		newsize = roundup((unit + 1),
1689 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1690 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1691 		if (!newlist)
1692 			return (ENOMEM);
1693 		if (oldlist != NULL)
1694 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1695 		bzero(newlist + dc->maxunit,
1696 		    sizeof(device_t) * (newsize - dc->maxunit));
1697 		dc->devices = newlist;
1698 		dc->maxunit = newsize;
1699 		if (oldlist != NULL)
1700 			free(oldlist, M_BUS);
1701 	}
1702 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1703 
1704 	*unitp = unit;
1705 	return (0);
1706 }
1707 
1708 /**
1709  * @internal
1710  * @brief Add a device to a devclass
1711  *
1712  * A unit number is allocated for the device (using the device's
1713  * preferred unit number if any) and the device is registered in the
1714  * devclass. This allows the device to be looked up by its unit
1715  * number, e.g. by decoding a dev_t minor number.
1716  *
1717  * @param dc		the devclass to add to
1718  * @param dev		the device to add
1719  *
1720  * @retval 0		success
1721  * @retval EEXIST	the requested unit number is already allocated
1722  * @retval ENOMEM	memory allocation failure
1723  */
1724 static int
1725 devclass_add_device(devclass_t dc, device_t dev)
1726 {
1727 	int buflen, error;
1728 
1729 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1730 
1731 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1732 	if (buflen < 0)
1733 		return (ENOMEM);
1734 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1735 	if (!dev->nameunit)
1736 		return (ENOMEM);
1737 
1738 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1739 		free(dev->nameunit, M_BUS);
1740 		dev->nameunit = NULL;
1741 		return (error);
1742 	}
1743 	dc->devices[dev->unit] = dev;
1744 	dev->devclass = dc;
1745 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1746 
1747 	return (0);
1748 }
1749 
1750 /**
1751  * @internal
1752  * @brief Delete a device from a devclass
1753  *
1754  * The device is removed from the devclass's device list and its unit
1755  * number is freed.
1756 
1757  * @param dc		the devclass to delete from
1758  * @param dev		the device to delete
1759  *
1760  * @retval 0		success
1761  */
1762 static int
1763 devclass_delete_device(devclass_t dc, device_t dev)
1764 {
1765 	if (!dc || !dev)
1766 		return (0);
1767 
1768 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1769 
1770 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1771 		panic("devclass_delete_device: inconsistent device class");
1772 	dc->devices[dev->unit] = NULL;
1773 	if (dev->flags & DF_WILDCARD)
1774 		dev->unit = -1;
1775 	dev->devclass = NULL;
1776 	free(dev->nameunit, M_BUS);
1777 	dev->nameunit = NULL;
1778 
1779 	return (0);
1780 }
1781 
1782 /**
1783  * @internal
1784  * @brief Make a new device and add it as a child of @p parent
1785  *
1786  * @param parent	the parent of the new device
1787  * @param name		the devclass name of the new device or @c NULL
1788  *			to leave the devclass unspecified
1789  * @parem unit		the unit number of the new device of @c -1 to
1790  *			leave the unit number unspecified
1791  *
1792  * @returns the new device
1793  */
1794 static device_t
1795 make_device(device_t parent, const char *name, int unit)
1796 {
1797 	device_t dev;
1798 	devclass_t dc;
1799 
1800 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1801 
1802 	if (name) {
1803 		dc = devclass_find_internal(name, NULL, TRUE);
1804 		if (!dc) {
1805 			printf("make_device: can't find device class %s\n",
1806 			    name);
1807 			return (NULL);
1808 		}
1809 	} else {
1810 		dc = NULL;
1811 	}
1812 
1813 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1814 	if (!dev)
1815 		return (NULL);
1816 
1817 	dev->parent = parent;
1818 	TAILQ_INIT(&dev->children);
1819 	kobj_init((kobj_t) dev, &null_class);
1820 	dev->driver = NULL;
1821 	dev->devclass = NULL;
1822 	dev->unit = unit;
1823 	dev->nameunit = NULL;
1824 	dev->desc = NULL;
1825 	dev->busy = 0;
1826 	dev->devflags = 0;
1827 	dev->flags = DF_ENABLED;
1828 	dev->order = 0;
1829 	if (unit == -1)
1830 		dev->flags |= DF_WILDCARD;
1831 	if (name) {
1832 		dev->flags |= DF_FIXEDCLASS;
1833 		if (devclass_add_device(dc, dev)) {
1834 			kobj_delete((kobj_t) dev, M_BUS);
1835 			return (NULL);
1836 		}
1837 	}
1838 	if (parent != NULL && device_has_quiet_children(parent))
1839 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1840 	dev->ivars = NULL;
1841 	dev->softc = NULL;
1842 
1843 	dev->state = DS_NOTPRESENT;
1844 
1845 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1846 	bus_data_generation_update();
1847 
1848 	return (dev);
1849 }
1850 
1851 /**
1852  * @internal
1853  * @brief Print a description of a device.
1854  */
1855 static int
1856 device_print_child(device_t dev, device_t child)
1857 {
1858 	int retval = 0;
1859 
1860 	if (device_is_alive(child))
1861 		retval += BUS_PRINT_CHILD(dev, child);
1862 	else
1863 		retval += device_printf(child, " not found\n");
1864 
1865 	return (retval);
1866 }
1867 
1868 /**
1869  * @brief Create a new device
1870  *
1871  * This creates a new device and adds it as a child of an existing
1872  * parent device. The new device will be added after the last existing
1873  * child with order zero.
1874  *
1875  * @param dev		the device which will be the parent of the
1876  *			new child device
1877  * @param name		devclass name for new device or @c NULL if not
1878  *			specified
1879  * @param unit		unit number for new device or @c -1 if not
1880  *			specified
1881  *
1882  * @returns		the new device
1883  */
1884 device_t
1885 device_add_child(device_t dev, const char *name, int unit)
1886 {
1887 	return (device_add_child_ordered(dev, 0, name, unit));
1888 }
1889 
1890 /**
1891  * @brief Create a new device
1892  *
1893  * This creates a new device and adds it as a child of an existing
1894  * parent device. The new device will be added after the last existing
1895  * child with the same order.
1896  *
1897  * @param dev		the device which will be the parent of the
1898  *			new child device
1899  * @param order		a value which is used to partially sort the
1900  *			children of @p dev - devices created using
1901  *			lower values of @p order appear first in @p
1902  *			dev's list of children
1903  * @param name		devclass name for new device or @c NULL if not
1904  *			specified
1905  * @param unit		unit number for new device or @c -1 if not
1906  *			specified
1907  *
1908  * @returns		the new device
1909  */
1910 device_t
1911 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1912 {
1913 	device_t child;
1914 	device_t place;
1915 
1916 	PDEBUG(("%s at %s with order %u as unit %d",
1917 	    name, DEVICENAME(dev), order, unit));
1918 	KASSERT(name != NULL || unit == -1,
1919 	    ("child device with wildcard name and specific unit number"));
1920 
1921 	child = make_device(dev, name, unit);
1922 	if (child == NULL)
1923 		return (child);
1924 	child->order = order;
1925 
1926 	TAILQ_FOREACH(place, &dev->children, link) {
1927 		if (place->order > order)
1928 			break;
1929 	}
1930 
1931 	if (place) {
1932 		/*
1933 		 * The device 'place' is the first device whose order is
1934 		 * greater than the new child.
1935 		 */
1936 		TAILQ_INSERT_BEFORE(place, child, link);
1937 	} else {
1938 		/*
1939 		 * The new child's order is greater or equal to the order of
1940 		 * any existing device. Add the child to the tail of the list.
1941 		 */
1942 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1943 	}
1944 
1945 	bus_data_generation_update();
1946 	return (child);
1947 }
1948 
1949 /**
1950  * @brief Delete a device
1951  *
1952  * This function deletes a device along with all of its children. If
1953  * the device currently has a driver attached to it, the device is
1954  * detached first using device_detach().
1955  *
1956  * @param dev		the parent device
1957  * @param child		the device to delete
1958  *
1959  * @retval 0		success
1960  * @retval non-zero	a unit error code describing the error
1961  */
1962 int
1963 device_delete_child(device_t dev, device_t child)
1964 {
1965 	int error;
1966 	device_t grandchild;
1967 
1968 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1969 
1970 	/* detach parent before deleting children, if any */
1971 	if ((error = device_detach(child)) != 0)
1972 		return (error);
1973 
1974 	/* remove children second */
1975 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1976 		error = device_delete_child(child, grandchild);
1977 		if (error)
1978 			return (error);
1979 	}
1980 
1981 	if (child->devclass)
1982 		devclass_delete_device(child->devclass, child);
1983 	if (child->parent)
1984 		BUS_CHILD_DELETED(dev, child);
1985 	TAILQ_REMOVE(&dev->children, child, link);
1986 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1987 	kobj_delete((kobj_t) child, M_BUS);
1988 
1989 	bus_data_generation_update();
1990 	return (0);
1991 }
1992 
1993 /**
1994  * @brief Delete all children devices of the given device, if any.
1995  *
1996  * This function deletes all children devices of the given device, if
1997  * any, using the device_delete_child() function for each device it
1998  * finds. If a child device cannot be deleted, this function will
1999  * return an error code.
2000  *
2001  * @param dev		the parent device
2002  *
2003  * @retval 0		success
2004  * @retval non-zero	a device would not detach
2005  */
2006 int
2007 device_delete_children(device_t dev)
2008 {
2009 	device_t child;
2010 	int error;
2011 
2012 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2013 
2014 	error = 0;
2015 
2016 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2017 		error = device_delete_child(dev, child);
2018 		if (error) {
2019 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2020 			break;
2021 		}
2022 	}
2023 	return (error);
2024 }
2025 
2026 /**
2027  * @brief Find a device given a unit number
2028  *
2029  * This is similar to devclass_get_devices() but only searches for
2030  * devices which have @p dev as a parent.
2031  *
2032  * @param dev		the parent device to search
2033  * @param unit		the unit number to search for.  If the unit is -1,
2034  *			return the first child of @p dev which has name
2035  *			@p classname (that is, the one with the lowest unit.)
2036  *
2037  * @returns		the device with the given unit number or @c
2038  *			NULL if there is no such device
2039  */
2040 device_t
2041 device_find_child(device_t dev, const char *classname, int unit)
2042 {
2043 	devclass_t dc;
2044 	device_t child;
2045 
2046 	dc = devclass_find(classname);
2047 	if (!dc)
2048 		return (NULL);
2049 
2050 	if (unit != -1) {
2051 		child = devclass_get_device(dc, unit);
2052 		if (child && child->parent == dev)
2053 			return (child);
2054 	} else {
2055 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2056 			child = devclass_get_device(dc, unit);
2057 			if (child && child->parent == dev)
2058 				return (child);
2059 		}
2060 	}
2061 	return (NULL);
2062 }
2063 
2064 /**
2065  * @internal
2066  */
2067 static driverlink_t
2068 first_matching_driver(devclass_t dc, device_t dev)
2069 {
2070 	if (dev->devclass)
2071 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2072 	return (TAILQ_FIRST(&dc->drivers));
2073 }
2074 
2075 /**
2076  * @internal
2077  */
2078 static driverlink_t
2079 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2080 {
2081 	if (dev->devclass) {
2082 		driverlink_t dl;
2083 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2084 			if (!strcmp(dev->devclass->name, dl->driver->name))
2085 				return (dl);
2086 		return (NULL);
2087 	}
2088 	return (TAILQ_NEXT(last, link));
2089 }
2090 
2091 /**
2092  * @internal
2093  */
2094 int
2095 device_probe_child(device_t dev, device_t child)
2096 {
2097 	devclass_t dc;
2098 	driverlink_t best = NULL;
2099 	driverlink_t dl;
2100 	int result, pri = 0;
2101 	int hasclass = (child->devclass != NULL);
2102 
2103 	GIANT_REQUIRED;
2104 
2105 	dc = dev->devclass;
2106 	if (!dc)
2107 		panic("device_probe_child: parent device has no devclass");
2108 
2109 	/*
2110 	 * If the state is already probed, then return.  However, don't
2111 	 * return if we can rebid this object.
2112 	 */
2113 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2114 		return (0);
2115 
2116 	for (; dc; dc = dc->parent) {
2117 		for (dl = first_matching_driver(dc, child);
2118 		     dl;
2119 		     dl = next_matching_driver(dc, child, dl)) {
2120 			/* If this driver's pass is too high, then ignore it. */
2121 			if (dl->pass > bus_current_pass)
2122 				continue;
2123 
2124 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2125 			result = device_set_driver(child, dl->driver);
2126 			if (result == ENOMEM)
2127 				return (result);
2128 			else if (result != 0)
2129 				continue;
2130 			if (!hasclass) {
2131 				if (device_set_devclass(child,
2132 				    dl->driver->name) != 0) {
2133 					char const * devname =
2134 					    device_get_name(child);
2135 					if (devname == NULL)
2136 						devname = "(unknown)";
2137 					printf("driver bug: Unable to set "
2138 					    "devclass (class: %s "
2139 					    "devname: %s)\n",
2140 					    dl->driver->name,
2141 					    devname);
2142 					(void)device_set_driver(child, NULL);
2143 					continue;
2144 				}
2145 			}
2146 
2147 			/* Fetch any flags for the device before probing. */
2148 			resource_int_value(dl->driver->name, child->unit,
2149 			    "flags", &child->devflags);
2150 
2151 			result = DEVICE_PROBE(child);
2152 
2153 			/* Reset flags and devclass before the next probe. */
2154 			child->devflags = 0;
2155 			if (!hasclass)
2156 				(void)device_set_devclass(child, NULL);
2157 
2158 			/*
2159 			 * If the driver returns SUCCESS, there can be
2160 			 * no higher match for this device.
2161 			 */
2162 			if (result == 0) {
2163 				best = dl;
2164 				pri = 0;
2165 				break;
2166 			}
2167 
2168 			/*
2169 			 * Reset DF_QUIET in case this driver doesn't
2170 			 * end up as the best driver.
2171 			 */
2172 			device_verbose(child);
2173 
2174 			/*
2175 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2176 			 * only match on devices whose driver was explicitly
2177 			 * specified.
2178 			 */
2179 			if (result <= BUS_PROBE_NOWILDCARD &&
2180 			    !(child->flags & DF_FIXEDCLASS)) {
2181 				result = ENXIO;
2182 			}
2183 
2184 			/*
2185 			 * The driver returned an error so it
2186 			 * certainly doesn't match.
2187 			 */
2188 			if (result > 0) {
2189 				(void)device_set_driver(child, NULL);
2190 				continue;
2191 			}
2192 
2193 			/*
2194 			 * A priority lower than SUCCESS, remember the
2195 			 * best matching driver. Initialise the value
2196 			 * of pri for the first match.
2197 			 */
2198 			if (best == NULL || result > pri) {
2199 				best = dl;
2200 				pri = result;
2201 				continue;
2202 			}
2203 		}
2204 		/*
2205 		 * If we have an unambiguous match in this devclass,
2206 		 * don't look in the parent.
2207 		 */
2208 		if (best && pri == 0)
2209 			break;
2210 	}
2211 
2212 	/*
2213 	 * If we found a driver, change state and initialise the devclass.
2214 	 */
2215 	/* XXX What happens if we rebid and got no best? */
2216 	if (best) {
2217 		/*
2218 		 * If this device was attached, and we were asked to
2219 		 * rescan, and it is a different driver, then we have
2220 		 * to detach the old driver and reattach this new one.
2221 		 * Note, we don't have to check for DF_REBID here
2222 		 * because if the state is > DS_ALIVE, we know it must
2223 		 * be.
2224 		 *
2225 		 * This assumes that all DF_REBID drivers can have
2226 		 * their probe routine called at any time and that
2227 		 * they are idempotent as well as completely benign in
2228 		 * normal operations.
2229 		 *
2230 		 * We also have to make sure that the detach
2231 		 * succeeded, otherwise we fail the operation (or
2232 		 * maybe it should just fail silently?  I'm torn).
2233 		 */
2234 		if (child->state > DS_ALIVE && best->driver != child->driver)
2235 			if ((result = device_detach(dev)) != 0)
2236 				return (result);
2237 
2238 		/* Set the winning driver, devclass, and flags. */
2239 		if (!child->devclass) {
2240 			result = device_set_devclass(child, best->driver->name);
2241 			if (result != 0)
2242 				return (result);
2243 		}
2244 		result = device_set_driver(child, best->driver);
2245 		if (result != 0)
2246 			return (result);
2247 		resource_int_value(best->driver->name, child->unit,
2248 		    "flags", &child->devflags);
2249 
2250 		if (pri < 0) {
2251 			/*
2252 			 * A bit bogus. Call the probe method again to make
2253 			 * sure that we have the right description.
2254 			 */
2255 			DEVICE_PROBE(child);
2256 #if 0
2257 			child->flags |= DF_REBID;
2258 #endif
2259 		} else
2260 			child->flags &= ~DF_REBID;
2261 		child->state = DS_ALIVE;
2262 
2263 		bus_data_generation_update();
2264 		return (0);
2265 	}
2266 
2267 	return (ENXIO);
2268 }
2269 
2270 /**
2271  * @brief Return the parent of a device
2272  */
2273 device_t
2274 device_get_parent(device_t dev)
2275 {
2276 	return (dev->parent);
2277 }
2278 
2279 /**
2280  * @brief Get a list of children of a device
2281  *
2282  * An array containing a list of all the children of the given device
2283  * is allocated and returned in @p *devlistp. The number of devices
2284  * in the array is returned in @p *devcountp. The caller should free
2285  * the array using @c free(p, M_TEMP).
2286  *
2287  * @param dev		the device to examine
2288  * @param devlistp	points at location for array pointer return
2289  *			value
2290  * @param devcountp	points at location for array size return value
2291  *
2292  * @retval 0		success
2293  * @retval ENOMEM	the array allocation failed
2294  */
2295 int
2296 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2297 {
2298 	int count;
2299 	device_t child;
2300 	device_t *list;
2301 
2302 	count = 0;
2303 	TAILQ_FOREACH(child, &dev->children, link) {
2304 		count++;
2305 	}
2306 	if (count == 0) {
2307 		*devlistp = NULL;
2308 		*devcountp = 0;
2309 		return (0);
2310 	}
2311 
2312 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2313 	if (!list)
2314 		return (ENOMEM);
2315 
2316 	count = 0;
2317 	TAILQ_FOREACH(child, &dev->children, link) {
2318 		list[count] = child;
2319 		count++;
2320 	}
2321 
2322 	*devlistp = list;
2323 	*devcountp = count;
2324 
2325 	return (0);
2326 }
2327 
2328 /**
2329  * @brief Return the current driver for the device or @c NULL if there
2330  * is no driver currently attached
2331  */
2332 driver_t *
2333 device_get_driver(device_t dev)
2334 {
2335 	return (dev->driver);
2336 }
2337 
2338 /**
2339  * @brief Return the current devclass for the device or @c NULL if
2340  * there is none.
2341  */
2342 devclass_t
2343 device_get_devclass(device_t dev)
2344 {
2345 	return (dev->devclass);
2346 }
2347 
2348 /**
2349  * @brief Return the name of the device's devclass or @c NULL if there
2350  * is none.
2351  */
2352 const char *
2353 device_get_name(device_t dev)
2354 {
2355 	if (dev != NULL && dev->devclass)
2356 		return (devclass_get_name(dev->devclass));
2357 	return (NULL);
2358 }
2359 
2360 /**
2361  * @brief Return a string containing the device's devclass name
2362  * followed by an ascii representation of the device's unit number
2363  * (e.g. @c "foo2").
2364  */
2365 const char *
2366 device_get_nameunit(device_t dev)
2367 {
2368 	return (dev->nameunit);
2369 }
2370 
2371 /**
2372  * @brief Return the device's unit number.
2373  */
2374 int
2375 device_get_unit(device_t dev)
2376 {
2377 	return (dev->unit);
2378 }
2379 
2380 /**
2381  * @brief Return the device's description string
2382  */
2383 const char *
2384 device_get_desc(device_t dev)
2385 {
2386 	return (dev->desc);
2387 }
2388 
2389 /**
2390  * @brief Return the device's flags
2391  */
2392 uint32_t
2393 device_get_flags(device_t dev)
2394 {
2395 	return (dev->devflags);
2396 }
2397 
2398 struct sysctl_ctx_list *
2399 device_get_sysctl_ctx(device_t dev)
2400 {
2401 	return (&dev->sysctl_ctx);
2402 }
2403 
2404 struct sysctl_oid *
2405 device_get_sysctl_tree(device_t dev)
2406 {
2407 	return (dev->sysctl_tree);
2408 }
2409 
2410 /**
2411  * @brief Print the name of the device followed by a colon and a space
2412  *
2413  * @returns the number of characters printed
2414  */
2415 int
2416 device_print_prettyname(device_t dev)
2417 {
2418 	const char *name = device_get_name(dev);
2419 
2420 	if (name == NULL)
2421 		return (printf("unknown: "));
2422 	return (printf("%s%d: ", name, device_get_unit(dev)));
2423 }
2424 
2425 /**
2426  * @brief Print the name of the device followed by a colon, a space
2427  * and the result of calling vprintf() with the value of @p fmt and
2428  * the following arguments.
2429  *
2430  * @returns the number of characters printed
2431  */
2432 int
2433 device_printf(device_t dev, const char * fmt, ...)
2434 {
2435 	char buf[128];
2436 	struct sbuf sb;
2437 	const char *name;
2438 	va_list ap;
2439 	size_t retval;
2440 
2441 	retval = 0;
2442 
2443 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2444 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2445 
2446 	name = device_get_name(dev);
2447 
2448 	if (name == NULL)
2449 		sbuf_cat(&sb, "unknown: ");
2450 	else
2451 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2452 
2453 	va_start(ap, fmt);
2454 	sbuf_vprintf(&sb, fmt, ap);
2455 	va_end(ap);
2456 
2457 	sbuf_finish(&sb);
2458 	sbuf_delete(&sb);
2459 
2460 	return (retval);
2461 }
2462 
2463 /**
2464  * @internal
2465  */
2466 static void
2467 device_set_desc_internal(device_t dev, const char* desc, int copy)
2468 {
2469 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2470 		free(dev->desc, M_BUS);
2471 		dev->flags &= ~DF_DESCMALLOCED;
2472 		dev->desc = NULL;
2473 	}
2474 
2475 	if (copy && desc) {
2476 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2477 		if (dev->desc) {
2478 			strcpy(dev->desc, desc);
2479 			dev->flags |= DF_DESCMALLOCED;
2480 		}
2481 	} else {
2482 		/* Avoid a -Wcast-qual warning */
2483 		dev->desc = (char *)(uintptr_t) desc;
2484 	}
2485 
2486 	bus_data_generation_update();
2487 }
2488 
2489 /**
2490  * @brief Set the device's description
2491  *
2492  * The value of @c desc should be a string constant that will not
2493  * change (at least until the description is changed in a subsequent
2494  * call to device_set_desc() or device_set_desc_copy()).
2495  */
2496 void
2497 device_set_desc(device_t dev, const char* desc)
2498 {
2499 	device_set_desc_internal(dev, desc, FALSE);
2500 }
2501 
2502 /**
2503  * @brief Set the device's description
2504  *
2505  * The string pointed to by @c desc is copied. Use this function if
2506  * the device description is generated, (e.g. with sprintf()).
2507  */
2508 void
2509 device_set_desc_copy(device_t dev, const char* desc)
2510 {
2511 	device_set_desc_internal(dev, desc, TRUE);
2512 }
2513 
2514 /**
2515  * @brief Set the device's flags
2516  */
2517 void
2518 device_set_flags(device_t dev, uint32_t flags)
2519 {
2520 	dev->devflags = flags;
2521 }
2522 
2523 /**
2524  * @brief Return the device's softc field
2525  *
2526  * The softc is allocated and zeroed when a driver is attached, based
2527  * on the size field of the driver.
2528  */
2529 void *
2530 device_get_softc(device_t dev)
2531 {
2532 	return (dev->softc);
2533 }
2534 
2535 /**
2536  * @brief Set the device's softc field
2537  *
2538  * Most drivers do not need to use this since the softc is allocated
2539  * automatically when the driver is attached.
2540  */
2541 void
2542 device_set_softc(device_t dev, void *softc)
2543 {
2544 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2545 		free_domain(dev->softc, M_BUS_SC);
2546 	dev->softc = softc;
2547 	if (dev->softc)
2548 		dev->flags |= DF_EXTERNALSOFTC;
2549 	else
2550 		dev->flags &= ~DF_EXTERNALSOFTC;
2551 }
2552 
2553 /**
2554  * @brief Free claimed softc
2555  *
2556  * Most drivers do not need to use this since the softc is freed
2557  * automatically when the driver is detached.
2558  */
2559 void
2560 device_free_softc(void *softc)
2561 {
2562 	free_domain(softc, M_BUS_SC);
2563 }
2564 
2565 /**
2566  * @brief Claim softc
2567  *
2568  * This function can be used to let the driver free the automatically
2569  * allocated softc using "device_free_softc()". This function is
2570  * useful when the driver is refcounting the softc and the softc
2571  * cannot be freed when the "device_detach" method is called.
2572  */
2573 void
2574 device_claim_softc(device_t dev)
2575 {
2576 	if (dev->softc)
2577 		dev->flags |= DF_EXTERNALSOFTC;
2578 	else
2579 		dev->flags &= ~DF_EXTERNALSOFTC;
2580 }
2581 
2582 /**
2583  * @brief Get the device's ivars field
2584  *
2585  * The ivars field is used by the parent device to store per-device
2586  * state (e.g. the physical location of the device or a list of
2587  * resources).
2588  */
2589 void *
2590 device_get_ivars(device_t dev)
2591 {
2592 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2593 	return (dev->ivars);
2594 }
2595 
2596 /**
2597  * @brief Set the device's ivars field
2598  */
2599 void
2600 device_set_ivars(device_t dev, void * ivars)
2601 {
2602 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2603 	dev->ivars = ivars;
2604 }
2605 
2606 /**
2607  * @brief Return the device's state
2608  */
2609 device_state_t
2610 device_get_state(device_t dev)
2611 {
2612 	return (dev->state);
2613 }
2614 
2615 /**
2616  * @brief Set the DF_ENABLED flag for the device
2617  */
2618 void
2619 device_enable(device_t dev)
2620 {
2621 	dev->flags |= DF_ENABLED;
2622 }
2623 
2624 /**
2625  * @brief Clear the DF_ENABLED flag for the device
2626  */
2627 void
2628 device_disable(device_t dev)
2629 {
2630 	dev->flags &= ~DF_ENABLED;
2631 }
2632 
2633 /**
2634  * @brief Increment the busy counter for the device
2635  */
2636 void
2637 device_busy(device_t dev)
2638 {
2639 	if (dev->state < DS_ATTACHING)
2640 		panic("device_busy: called for unattached device");
2641 	if (dev->busy == 0 && dev->parent)
2642 		device_busy(dev->parent);
2643 	dev->busy++;
2644 	if (dev->state == DS_ATTACHED)
2645 		dev->state = DS_BUSY;
2646 }
2647 
2648 /**
2649  * @brief Decrement the busy counter for the device
2650  */
2651 void
2652 device_unbusy(device_t dev)
2653 {
2654 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2655 	    dev->state != DS_ATTACHING)
2656 		panic("device_unbusy: called for non-busy device %s",
2657 		    device_get_nameunit(dev));
2658 	dev->busy--;
2659 	if (dev->busy == 0) {
2660 		if (dev->parent)
2661 			device_unbusy(dev->parent);
2662 		if (dev->state == DS_BUSY)
2663 			dev->state = DS_ATTACHED;
2664 	}
2665 }
2666 
2667 /**
2668  * @brief Set the DF_QUIET flag for the device
2669  */
2670 void
2671 device_quiet(device_t dev)
2672 {
2673 	dev->flags |= DF_QUIET;
2674 }
2675 
2676 /**
2677  * @brief Set the DF_QUIET_CHILDREN flag for the device
2678  */
2679 void
2680 device_quiet_children(device_t dev)
2681 {
2682 	dev->flags |= DF_QUIET_CHILDREN;
2683 }
2684 
2685 /**
2686  * @brief Clear the DF_QUIET flag for the device
2687  */
2688 void
2689 device_verbose(device_t dev)
2690 {
2691 	dev->flags &= ~DF_QUIET;
2692 }
2693 
2694 /**
2695  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2696  */
2697 int
2698 device_has_quiet_children(device_t dev)
2699 {
2700 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2701 }
2702 
2703 /**
2704  * @brief Return non-zero if the DF_QUIET flag is set on the device
2705  */
2706 int
2707 device_is_quiet(device_t dev)
2708 {
2709 	return ((dev->flags & DF_QUIET) != 0);
2710 }
2711 
2712 /**
2713  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2714  */
2715 int
2716 device_is_enabled(device_t dev)
2717 {
2718 	return ((dev->flags & DF_ENABLED) != 0);
2719 }
2720 
2721 /**
2722  * @brief Return non-zero if the device was successfully probed
2723  */
2724 int
2725 device_is_alive(device_t dev)
2726 {
2727 	return (dev->state >= DS_ALIVE);
2728 }
2729 
2730 /**
2731  * @brief Return non-zero if the device currently has a driver
2732  * attached to it
2733  */
2734 int
2735 device_is_attached(device_t dev)
2736 {
2737 	return (dev->state >= DS_ATTACHED);
2738 }
2739 
2740 /**
2741  * @brief Return non-zero if the device is currently suspended.
2742  */
2743 int
2744 device_is_suspended(device_t dev)
2745 {
2746 	return ((dev->flags & DF_SUSPENDED) != 0);
2747 }
2748 
2749 /**
2750  * @brief Set the devclass of a device
2751  * @see devclass_add_device().
2752  */
2753 int
2754 device_set_devclass(device_t dev, const char *classname)
2755 {
2756 	devclass_t dc;
2757 	int error;
2758 
2759 	if (!classname) {
2760 		if (dev->devclass)
2761 			devclass_delete_device(dev->devclass, dev);
2762 		return (0);
2763 	}
2764 
2765 	if (dev->devclass) {
2766 		printf("device_set_devclass: device class already set\n");
2767 		return (EINVAL);
2768 	}
2769 
2770 	dc = devclass_find_internal(classname, NULL, TRUE);
2771 	if (!dc)
2772 		return (ENOMEM);
2773 
2774 	error = devclass_add_device(dc, dev);
2775 
2776 	bus_data_generation_update();
2777 	return (error);
2778 }
2779 
2780 /**
2781  * @brief Set the devclass of a device and mark the devclass fixed.
2782  * @see device_set_devclass()
2783  */
2784 int
2785 device_set_devclass_fixed(device_t dev, const char *classname)
2786 {
2787 	int error;
2788 
2789 	if (classname == NULL)
2790 		return (EINVAL);
2791 
2792 	error = device_set_devclass(dev, classname);
2793 	if (error)
2794 		return (error);
2795 	dev->flags |= DF_FIXEDCLASS;
2796 	return (0);
2797 }
2798 
2799 /**
2800  * @brief Query the device to determine if it's of a fixed devclass
2801  * @see device_set_devclass_fixed()
2802  */
2803 bool
2804 device_is_devclass_fixed(device_t dev)
2805 {
2806 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2807 }
2808 
2809 /**
2810  * @brief Set the driver of a device
2811  *
2812  * @retval 0		success
2813  * @retval EBUSY	the device already has a driver attached
2814  * @retval ENOMEM	a memory allocation failure occurred
2815  */
2816 int
2817 device_set_driver(device_t dev, driver_t *driver)
2818 {
2819 	int domain;
2820 	struct domainset *policy;
2821 
2822 	if (dev->state >= DS_ATTACHED)
2823 		return (EBUSY);
2824 
2825 	if (dev->driver == driver)
2826 		return (0);
2827 
2828 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2829 		free_domain(dev->softc, M_BUS_SC);
2830 		dev->softc = NULL;
2831 	}
2832 	device_set_desc(dev, NULL);
2833 	kobj_delete((kobj_t) dev, NULL);
2834 	dev->driver = driver;
2835 	if (driver) {
2836 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2837 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2838 			if (bus_get_domain(dev, &domain) == 0)
2839 				policy = DOMAINSET_PREF(domain);
2840 			else
2841 				policy = DOMAINSET_RR();
2842 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2843 			    policy, M_NOWAIT | M_ZERO);
2844 			if (!dev->softc) {
2845 				kobj_delete((kobj_t) dev, NULL);
2846 				kobj_init((kobj_t) dev, &null_class);
2847 				dev->driver = NULL;
2848 				return (ENOMEM);
2849 			}
2850 		}
2851 	} else {
2852 		kobj_init((kobj_t) dev, &null_class);
2853 	}
2854 
2855 	bus_data_generation_update();
2856 	return (0);
2857 }
2858 
2859 /**
2860  * @brief Probe a device, and return this status.
2861  *
2862  * This function is the core of the device autoconfiguration
2863  * system. Its purpose is to select a suitable driver for a device and
2864  * then call that driver to initialise the hardware appropriately. The
2865  * driver is selected by calling the DEVICE_PROBE() method of a set of
2866  * candidate drivers and then choosing the driver which returned the
2867  * best value. This driver is then attached to the device using
2868  * device_attach().
2869  *
2870  * The set of suitable drivers is taken from the list of drivers in
2871  * the parent device's devclass. If the device was originally created
2872  * with a specific class name (see device_add_child()), only drivers
2873  * with that name are probed, otherwise all drivers in the devclass
2874  * are probed. If no drivers return successful probe values in the
2875  * parent devclass, the search continues in the parent of that
2876  * devclass (see devclass_get_parent()) if any.
2877  *
2878  * @param dev		the device to initialise
2879  *
2880  * @retval 0		success
2881  * @retval ENXIO	no driver was found
2882  * @retval ENOMEM	memory allocation failure
2883  * @retval non-zero	some other unix error code
2884  * @retval -1		Device already attached
2885  */
2886 int
2887 device_probe(device_t dev)
2888 {
2889 	int error;
2890 
2891 	GIANT_REQUIRED;
2892 
2893 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2894 		return (-1);
2895 
2896 	if (!(dev->flags & DF_ENABLED)) {
2897 		if (bootverbose && device_get_name(dev) != NULL) {
2898 			device_print_prettyname(dev);
2899 			printf("not probed (disabled)\n");
2900 		}
2901 		return (-1);
2902 	}
2903 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2904 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2905 		    !(dev->flags & DF_DONENOMATCH)) {
2906 			BUS_PROBE_NOMATCH(dev->parent, dev);
2907 			devnomatch(dev);
2908 			dev->flags |= DF_DONENOMATCH;
2909 		}
2910 		return (error);
2911 	}
2912 	return (0);
2913 }
2914 
2915 /**
2916  * @brief Probe a device and attach a driver if possible
2917  *
2918  * calls device_probe() and attaches if that was successful.
2919  */
2920 int
2921 device_probe_and_attach(device_t dev)
2922 {
2923 	int error;
2924 
2925 	GIANT_REQUIRED;
2926 
2927 	error = device_probe(dev);
2928 	if (error == -1)
2929 		return (0);
2930 	else if (error != 0)
2931 		return (error);
2932 
2933 	CURVNET_SET_QUIET(vnet0);
2934 	error = device_attach(dev);
2935 	CURVNET_RESTORE();
2936 	return error;
2937 }
2938 
2939 /**
2940  * @brief Attach a device driver to a device
2941  *
2942  * This function is a wrapper around the DEVICE_ATTACH() driver
2943  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2944  * device's sysctl tree, optionally prints a description of the device
2945  * and queues a notification event for user-based device management
2946  * services.
2947  *
2948  * Normally this function is only called internally from
2949  * device_probe_and_attach().
2950  *
2951  * @param dev		the device to initialise
2952  *
2953  * @retval 0		success
2954  * @retval ENXIO	no driver was found
2955  * @retval ENOMEM	memory allocation failure
2956  * @retval non-zero	some other unix error code
2957  */
2958 int
2959 device_attach(device_t dev)
2960 {
2961 	uint64_t attachtime;
2962 	uint16_t attachentropy;
2963 	int error;
2964 
2965 	if (resource_disabled(dev->driver->name, dev->unit)) {
2966 		device_disable(dev);
2967 		if (bootverbose)
2968 			 device_printf(dev, "disabled via hints entry\n");
2969 		return (ENXIO);
2970 	}
2971 
2972 	device_sysctl_init(dev);
2973 	if (!device_is_quiet(dev))
2974 		device_print_child(dev->parent, dev);
2975 	attachtime = get_cyclecount();
2976 	dev->state = DS_ATTACHING;
2977 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2978 		printf("device_attach: %s%d attach returned %d\n",
2979 		    dev->driver->name, dev->unit, error);
2980 		if (!(dev->flags & DF_FIXEDCLASS))
2981 			devclass_delete_device(dev->devclass, dev);
2982 		(void)device_set_driver(dev, NULL);
2983 		device_sysctl_fini(dev);
2984 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2985 		dev->state = DS_NOTPRESENT;
2986 		return (error);
2987 	}
2988 	dev->flags |= DF_ATTACHED_ONCE;
2989 	/* We only need the low bits of this time, but ranges from tens to thousands
2990 	 * have been seen, so keep 2 bytes' worth.
2991 	 */
2992 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
2993 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
2994 	device_sysctl_update(dev);
2995 	if (dev->busy)
2996 		dev->state = DS_BUSY;
2997 	else
2998 		dev->state = DS_ATTACHED;
2999 	dev->flags &= ~DF_DONENOMATCH;
3000 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3001 	devadded(dev);
3002 	return (0);
3003 }
3004 
3005 /**
3006  * @brief Detach a driver from a device
3007  *
3008  * This function is a wrapper around the DEVICE_DETACH() driver
3009  * method. If the call to DEVICE_DETACH() succeeds, it calls
3010  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3011  * notification event for user-based device management services and
3012  * cleans up the device's sysctl tree.
3013  *
3014  * @param dev		the device to un-initialise
3015  *
3016  * @retval 0		success
3017  * @retval ENXIO	no driver was found
3018  * @retval ENOMEM	memory allocation failure
3019  * @retval non-zero	some other unix error code
3020  */
3021 int
3022 device_detach(device_t dev)
3023 {
3024 	int error;
3025 
3026 	GIANT_REQUIRED;
3027 
3028 	PDEBUG(("%s", DEVICENAME(dev)));
3029 	if (dev->state == DS_BUSY)
3030 		return (EBUSY);
3031 	if (dev->state == DS_ATTACHING) {
3032 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3033 		return (EBUSY);
3034 	}
3035 	if (dev->state != DS_ATTACHED)
3036 		return (0);
3037 
3038 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3039 	if ((error = DEVICE_DETACH(dev)) != 0) {
3040 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3041 		    EVHDEV_DETACH_FAILED);
3042 		return (error);
3043 	} else {
3044 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3045 		    EVHDEV_DETACH_COMPLETE);
3046 	}
3047 	devremoved(dev);
3048 	if (!device_is_quiet(dev))
3049 		device_printf(dev, "detached\n");
3050 	if (dev->parent)
3051 		BUS_CHILD_DETACHED(dev->parent, dev);
3052 
3053 	if (!(dev->flags & DF_FIXEDCLASS))
3054 		devclass_delete_device(dev->devclass, dev);
3055 
3056 	device_verbose(dev);
3057 	dev->state = DS_NOTPRESENT;
3058 	(void)device_set_driver(dev, NULL);
3059 	device_sysctl_fini(dev);
3060 
3061 	return (0);
3062 }
3063 
3064 /**
3065  * @brief Tells a driver to quiesce itself.
3066  *
3067  * This function is a wrapper around the DEVICE_QUIESCE() driver
3068  * method. If the call to DEVICE_QUIESCE() succeeds.
3069  *
3070  * @param dev		the device to quiesce
3071  *
3072  * @retval 0		success
3073  * @retval ENXIO	no driver was found
3074  * @retval ENOMEM	memory allocation failure
3075  * @retval non-zero	some other unix error code
3076  */
3077 int
3078 device_quiesce(device_t dev)
3079 {
3080 	PDEBUG(("%s", DEVICENAME(dev)));
3081 	if (dev->state == DS_BUSY)
3082 		return (EBUSY);
3083 	if (dev->state != DS_ATTACHED)
3084 		return (0);
3085 
3086 	return (DEVICE_QUIESCE(dev));
3087 }
3088 
3089 /**
3090  * @brief Notify a device of system shutdown
3091  *
3092  * This function calls the DEVICE_SHUTDOWN() driver method if the
3093  * device currently has an attached driver.
3094  *
3095  * @returns the value returned by DEVICE_SHUTDOWN()
3096  */
3097 int
3098 device_shutdown(device_t dev)
3099 {
3100 	if (dev->state < DS_ATTACHED)
3101 		return (0);
3102 	return (DEVICE_SHUTDOWN(dev));
3103 }
3104 
3105 /**
3106  * @brief Set the unit number of a device
3107  *
3108  * This function can be used to override the unit number used for a
3109  * device (e.g. to wire a device to a pre-configured unit number).
3110  */
3111 int
3112 device_set_unit(device_t dev, int unit)
3113 {
3114 	devclass_t dc;
3115 	int err;
3116 
3117 	dc = device_get_devclass(dev);
3118 	if (unit < dc->maxunit && dc->devices[unit])
3119 		return (EBUSY);
3120 	err = devclass_delete_device(dc, dev);
3121 	if (err)
3122 		return (err);
3123 	dev->unit = unit;
3124 	err = devclass_add_device(dc, dev);
3125 	if (err)
3126 		return (err);
3127 
3128 	bus_data_generation_update();
3129 	return (0);
3130 }
3131 
3132 /*======================================*/
3133 /*
3134  * Some useful method implementations to make life easier for bus drivers.
3135  */
3136 
3137 void
3138 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3139 {
3140 	bzero(args, sz);
3141 	args->size = sz;
3142 	args->memattr = VM_MEMATTR_UNCACHEABLE;
3143 }
3144 
3145 /**
3146  * @brief Initialise a resource list.
3147  *
3148  * @param rl		the resource list to initialise
3149  */
3150 void
3151 resource_list_init(struct resource_list *rl)
3152 {
3153 	STAILQ_INIT(rl);
3154 }
3155 
3156 /**
3157  * @brief Reclaim memory used by a resource list.
3158  *
3159  * This function frees the memory for all resource entries on the list
3160  * (if any).
3161  *
3162  * @param rl		the resource list to free
3163  */
3164 void
3165 resource_list_free(struct resource_list *rl)
3166 {
3167 	struct resource_list_entry *rle;
3168 
3169 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3170 		if (rle->res)
3171 			panic("resource_list_free: resource entry is busy");
3172 		STAILQ_REMOVE_HEAD(rl, link);
3173 		free(rle, M_BUS);
3174 	}
3175 }
3176 
3177 /**
3178  * @brief Add a resource entry.
3179  *
3180  * This function adds a resource entry using the given @p type, @p
3181  * start, @p end and @p count values. A rid value is chosen by
3182  * searching sequentially for the first unused rid starting at zero.
3183  *
3184  * @param rl		the resource list to edit
3185  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3186  * @param start		the start address of the resource
3187  * @param end		the end address of the resource
3188  * @param count		XXX end-start+1
3189  */
3190 int
3191 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3192     rman_res_t end, rman_res_t count)
3193 {
3194 	int rid;
3195 
3196 	rid = 0;
3197 	while (resource_list_find(rl, type, rid) != NULL)
3198 		rid++;
3199 	resource_list_add(rl, type, rid, start, end, count);
3200 	return (rid);
3201 }
3202 
3203 /**
3204  * @brief Add or modify a resource entry.
3205  *
3206  * If an existing entry exists with the same type and rid, it will be
3207  * modified using the given values of @p start, @p end and @p
3208  * count. If no entry exists, a new one will be created using the
3209  * given values.  The resource list entry that matches is then returned.
3210  *
3211  * @param rl		the resource list to edit
3212  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3213  * @param rid		the resource identifier
3214  * @param start		the start address of the resource
3215  * @param end		the end address of the resource
3216  * @param count		XXX end-start+1
3217  */
3218 struct resource_list_entry *
3219 resource_list_add(struct resource_list *rl, int type, int rid,
3220     rman_res_t start, rman_res_t end, rman_res_t count)
3221 {
3222 	struct resource_list_entry *rle;
3223 
3224 	rle = resource_list_find(rl, type, rid);
3225 	if (!rle) {
3226 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3227 		    M_NOWAIT);
3228 		if (!rle)
3229 			panic("resource_list_add: can't record entry");
3230 		STAILQ_INSERT_TAIL(rl, rle, link);
3231 		rle->type = type;
3232 		rle->rid = rid;
3233 		rle->res = NULL;
3234 		rle->flags = 0;
3235 	}
3236 
3237 	if (rle->res)
3238 		panic("resource_list_add: resource entry is busy");
3239 
3240 	rle->start = start;
3241 	rle->end = end;
3242 	rle->count = count;
3243 	return (rle);
3244 }
3245 
3246 /**
3247  * @brief Determine if a resource entry is busy.
3248  *
3249  * Returns true if a resource entry is busy meaning that it has an
3250  * associated resource that is not an unallocated "reserved" resource.
3251  *
3252  * @param rl		the resource list to search
3253  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3254  * @param rid		the resource identifier
3255  *
3256  * @returns Non-zero if the entry is busy, zero otherwise.
3257  */
3258 int
3259 resource_list_busy(struct resource_list *rl, int type, int rid)
3260 {
3261 	struct resource_list_entry *rle;
3262 
3263 	rle = resource_list_find(rl, type, rid);
3264 	if (rle == NULL || rle->res == NULL)
3265 		return (0);
3266 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3267 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3268 		    ("reserved resource is active"));
3269 		return (0);
3270 	}
3271 	return (1);
3272 }
3273 
3274 /**
3275  * @brief Determine if a resource entry is reserved.
3276  *
3277  * Returns true if a resource entry is reserved meaning that it has an
3278  * associated "reserved" resource.  The resource can either be
3279  * allocated or unallocated.
3280  *
3281  * @param rl		the resource list to search
3282  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3283  * @param rid		the resource identifier
3284  *
3285  * @returns Non-zero if the entry is reserved, zero otherwise.
3286  */
3287 int
3288 resource_list_reserved(struct resource_list *rl, int type, int rid)
3289 {
3290 	struct resource_list_entry *rle;
3291 
3292 	rle = resource_list_find(rl, type, rid);
3293 	if (rle != NULL && rle->flags & RLE_RESERVED)
3294 		return (1);
3295 	return (0);
3296 }
3297 
3298 /**
3299  * @brief Find a resource entry by type and rid.
3300  *
3301  * @param rl		the resource list to search
3302  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3303  * @param rid		the resource identifier
3304  *
3305  * @returns the resource entry pointer or NULL if there is no such
3306  * entry.
3307  */
3308 struct resource_list_entry *
3309 resource_list_find(struct resource_list *rl, int type, int rid)
3310 {
3311 	struct resource_list_entry *rle;
3312 
3313 	STAILQ_FOREACH(rle, rl, link) {
3314 		if (rle->type == type && rle->rid == rid)
3315 			return (rle);
3316 	}
3317 	return (NULL);
3318 }
3319 
3320 /**
3321  * @brief Delete a resource entry.
3322  *
3323  * @param rl		the resource list to edit
3324  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3325  * @param rid		the resource identifier
3326  */
3327 void
3328 resource_list_delete(struct resource_list *rl, int type, int rid)
3329 {
3330 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3331 
3332 	if (rle) {
3333 		if (rle->res != NULL)
3334 			panic("resource_list_delete: resource has not been released");
3335 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3336 		free(rle, M_BUS);
3337 	}
3338 }
3339 
3340 /**
3341  * @brief Allocate a reserved resource
3342  *
3343  * This can be used by buses to force the allocation of resources
3344  * that are always active in the system even if they are not allocated
3345  * by a driver (e.g. PCI BARs).  This function is usually called when
3346  * adding a new child to the bus.  The resource is allocated from the
3347  * parent bus when it is reserved.  The resource list entry is marked
3348  * with RLE_RESERVED to note that it is a reserved resource.
3349  *
3350  * Subsequent attempts to allocate the resource with
3351  * resource_list_alloc() will succeed the first time and will set
3352  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3353  * resource that has been allocated is released with
3354  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3355  * the actual resource remains allocated.  The resource can be released to
3356  * the parent bus by calling resource_list_unreserve().
3357  *
3358  * @param rl		the resource list to allocate from
3359  * @param bus		the parent device of @p child
3360  * @param child		the device for which the resource is being reserved
3361  * @param type		the type of resource to allocate
3362  * @param rid		a pointer to the resource identifier
3363  * @param start		hint at the start of the resource range - pass
3364  *			@c 0 for any start address
3365  * @param end		hint at the end of the resource range - pass
3366  *			@c ~0 for any end address
3367  * @param count		hint at the size of range required - pass @c 1
3368  *			for any size
3369  * @param flags		any extra flags to control the resource
3370  *			allocation - see @c RF_XXX flags in
3371  *			<sys/rman.h> for details
3372  *
3373  * @returns		the resource which was allocated or @c NULL if no
3374  *			resource could be allocated
3375  */
3376 struct resource *
3377 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3378     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3379 {
3380 	struct resource_list_entry *rle = NULL;
3381 	int passthrough = (device_get_parent(child) != bus);
3382 	struct resource *r;
3383 
3384 	if (passthrough)
3385 		panic(
3386     "resource_list_reserve() should only be called for direct children");
3387 	if (flags & RF_ACTIVE)
3388 		panic(
3389     "resource_list_reserve() should only reserve inactive resources");
3390 
3391 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3392 	    flags);
3393 	if (r != NULL) {
3394 		rle = resource_list_find(rl, type, *rid);
3395 		rle->flags |= RLE_RESERVED;
3396 	}
3397 	return (r);
3398 }
3399 
3400 /**
3401  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3402  *
3403  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3404  * and passing the allocation up to the parent of @p bus. This assumes
3405  * that the first entry of @c device_get_ivars(child) is a struct
3406  * resource_list. This also handles 'passthrough' allocations where a
3407  * child is a remote descendant of bus by passing the allocation up to
3408  * the parent of bus.
3409  *
3410  * Typically, a bus driver would store a list of child resources
3411  * somewhere in the child device's ivars (see device_get_ivars()) and
3412  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3413  * then call resource_list_alloc() to perform the allocation.
3414  *
3415  * @param rl		the resource list to allocate from
3416  * @param bus		the parent device of @p child
3417  * @param child		the device which is requesting an allocation
3418  * @param type		the type of resource to allocate
3419  * @param rid		a pointer to the resource identifier
3420  * @param start		hint at the start of the resource range - pass
3421  *			@c 0 for any start address
3422  * @param end		hint at the end of the resource range - pass
3423  *			@c ~0 for any end address
3424  * @param count		hint at the size of range required - pass @c 1
3425  *			for any size
3426  * @param flags		any extra flags to control the resource
3427  *			allocation - see @c RF_XXX flags in
3428  *			<sys/rman.h> for details
3429  *
3430  * @returns		the resource which was allocated or @c NULL if no
3431  *			resource could be allocated
3432  */
3433 struct resource *
3434 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3435     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3436 {
3437 	struct resource_list_entry *rle = NULL;
3438 	int passthrough = (device_get_parent(child) != bus);
3439 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3440 
3441 	if (passthrough) {
3442 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3443 		    type, rid, start, end, count, flags));
3444 	}
3445 
3446 	rle = resource_list_find(rl, type, *rid);
3447 
3448 	if (!rle)
3449 		return (NULL);		/* no resource of that type/rid */
3450 
3451 	if (rle->res) {
3452 		if (rle->flags & RLE_RESERVED) {
3453 			if (rle->flags & RLE_ALLOCATED)
3454 				return (NULL);
3455 			if ((flags & RF_ACTIVE) &&
3456 			    bus_activate_resource(child, type, *rid,
3457 			    rle->res) != 0)
3458 				return (NULL);
3459 			rle->flags |= RLE_ALLOCATED;
3460 			return (rle->res);
3461 		}
3462 		device_printf(bus,
3463 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3464 		    type, device_get_nameunit(child));
3465 		return (NULL);
3466 	}
3467 
3468 	if (isdefault) {
3469 		start = rle->start;
3470 		count = ulmax(count, rle->count);
3471 		end = ulmax(rle->end, start + count - 1);
3472 	}
3473 
3474 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3475 	    type, rid, start, end, count, flags);
3476 
3477 	/*
3478 	 * Record the new range.
3479 	 */
3480 	if (rle->res) {
3481 		rle->start = rman_get_start(rle->res);
3482 		rle->end = rman_get_end(rle->res);
3483 		rle->count = count;
3484 	}
3485 
3486 	return (rle->res);
3487 }
3488 
3489 /**
3490  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3491  *
3492  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3493  * used with resource_list_alloc().
3494  *
3495  * @param rl		the resource list which was allocated from
3496  * @param bus		the parent device of @p child
3497  * @param child		the device which is requesting a release
3498  * @param type		the type of resource to release
3499  * @param rid		the resource identifier
3500  * @param res		the resource to release
3501  *
3502  * @retval 0		success
3503  * @retval non-zero	a standard unix error code indicating what
3504  *			error condition prevented the operation
3505  */
3506 int
3507 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3508     int type, int rid, struct resource *res)
3509 {
3510 	struct resource_list_entry *rle = NULL;
3511 	int passthrough = (device_get_parent(child) != bus);
3512 	int error;
3513 
3514 	if (passthrough) {
3515 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3516 		    type, rid, res));
3517 	}
3518 
3519 	rle = resource_list_find(rl, type, rid);
3520 
3521 	if (!rle)
3522 		panic("resource_list_release: can't find resource");
3523 	if (!rle->res)
3524 		panic("resource_list_release: resource entry is not busy");
3525 	if (rle->flags & RLE_RESERVED) {
3526 		if (rle->flags & RLE_ALLOCATED) {
3527 			if (rman_get_flags(res) & RF_ACTIVE) {
3528 				error = bus_deactivate_resource(child, type,
3529 				    rid, res);
3530 				if (error)
3531 					return (error);
3532 			}
3533 			rle->flags &= ~RLE_ALLOCATED;
3534 			return (0);
3535 		}
3536 		return (EINVAL);
3537 	}
3538 
3539 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3540 	    type, rid, res);
3541 	if (error)
3542 		return (error);
3543 
3544 	rle->res = NULL;
3545 	return (0);
3546 }
3547 
3548 /**
3549  * @brief Release all active resources of a given type
3550  *
3551  * Release all active resources of a specified type.  This is intended
3552  * to be used to cleanup resources leaked by a driver after detach or
3553  * a failed attach.
3554  *
3555  * @param rl		the resource list which was allocated from
3556  * @param bus		the parent device of @p child
3557  * @param child		the device whose active resources are being released
3558  * @param type		the type of resources to release
3559  *
3560  * @retval 0		success
3561  * @retval EBUSY	at least one resource was active
3562  */
3563 int
3564 resource_list_release_active(struct resource_list *rl, device_t bus,
3565     device_t child, int type)
3566 {
3567 	struct resource_list_entry *rle;
3568 	int error, retval;
3569 
3570 	retval = 0;
3571 	STAILQ_FOREACH(rle, rl, link) {
3572 		if (rle->type != type)
3573 			continue;
3574 		if (rle->res == NULL)
3575 			continue;
3576 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3577 		    RLE_RESERVED)
3578 			continue;
3579 		retval = EBUSY;
3580 		error = resource_list_release(rl, bus, child, type,
3581 		    rman_get_rid(rle->res), rle->res);
3582 		if (error != 0)
3583 			device_printf(bus,
3584 			    "Failed to release active resource: %d\n", error);
3585 	}
3586 	return (retval);
3587 }
3588 
3589 /**
3590  * @brief Fully release a reserved resource
3591  *
3592  * Fully releases a resource reserved via resource_list_reserve().
3593  *
3594  * @param rl		the resource list which was allocated from
3595  * @param bus		the parent device of @p child
3596  * @param child		the device whose reserved resource is being released
3597  * @param type		the type of resource to release
3598  * @param rid		the resource identifier
3599  * @param res		the resource to release
3600  *
3601  * @retval 0		success
3602  * @retval non-zero	a standard unix error code indicating what
3603  *			error condition prevented the operation
3604  */
3605 int
3606 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3607     int type, int rid)
3608 {
3609 	struct resource_list_entry *rle = NULL;
3610 	int passthrough = (device_get_parent(child) != bus);
3611 
3612 	if (passthrough)
3613 		panic(
3614     "resource_list_unreserve() should only be called for direct children");
3615 
3616 	rle = resource_list_find(rl, type, rid);
3617 
3618 	if (!rle)
3619 		panic("resource_list_unreserve: can't find resource");
3620 	if (!(rle->flags & RLE_RESERVED))
3621 		return (EINVAL);
3622 	if (rle->flags & RLE_ALLOCATED)
3623 		return (EBUSY);
3624 	rle->flags &= ~RLE_RESERVED;
3625 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3626 }
3627 
3628 /**
3629  * @brief Print a description of resources in a resource list
3630  *
3631  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3632  * The name is printed if at least one resource of the given type is available.
3633  * The format is used to print resource start and end.
3634  *
3635  * @param rl		the resource list to print
3636  * @param name		the name of @p type, e.g. @c "memory"
3637  * @param type		type type of resource entry to print
3638  * @param format	printf(9) format string to print resource
3639  *			start and end values
3640  *
3641  * @returns		the number of characters printed
3642  */
3643 int
3644 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3645     const char *format)
3646 {
3647 	struct resource_list_entry *rle;
3648 	int printed, retval;
3649 
3650 	printed = 0;
3651 	retval = 0;
3652 	/* Yes, this is kinda cheating */
3653 	STAILQ_FOREACH(rle, rl, link) {
3654 		if (rle->type == type) {
3655 			if (printed == 0)
3656 				retval += printf(" %s ", name);
3657 			else
3658 				retval += printf(",");
3659 			printed++;
3660 			retval += printf(format, rle->start);
3661 			if (rle->count > 1) {
3662 				retval += printf("-");
3663 				retval += printf(format, rle->start +
3664 						 rle->count - 1);
3665 			}
3666 		}
3667 	}
3668 	return (retval);
3669 }
3670 
3671 /**
3672  * @brief Releases all the resources in a list.
3673  *
3674  * @param rl		The resource list to purge.
3675  *
3676  * @returns		nothing
3677  */
3678 void
3679 resource_list_purge(struct resource_list *rl)
3680 {
3681 	struct resource_list_entry *rle;
3682 
3683 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3684 		if (rle->res)
3685 			bus_release_resource(rman_get_device(rle->res),
3686 			    rle->type, rle->rid, rle->res);
3687 		STAILQ_REMOVE_HEAD(rl, link);
3688 		free(rle, M_BUS);
3689 	}
3690 }
3691 
3692 device_t
3693 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3694 {
3695 	return (device_add_child_ordered(dev, order, name, unit));
3696 }
3697 
3698 /**
3699  * @brief Helper function for implementing DEVICE_PROBE()
3700  *
3701  * This function can be used to help implement the DEVICE_PROBE() for
3702  * a bus (i.e. a device which has other devices attached to it). It
3703  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3704  * devclass.
3705  */
3706 int
3707 bus_generic_probe(device_t dev)
3708 {
3709 	devclass_t dc = dev->devclass;
3710 	driverlink_t dl;
3711 
3712 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3713 		/*
3714 		 * If this driver's pass is too high, then ignore it.
3715 		 * For most drivers in the default pass, this will
3716 		 * never be true.  For early-pass drivers they will
3717 		 * only call the identify routines of eligible drivers
3718 		 * when this routine is called.  Drivers for later
3719 		 * passes should have their identify routines called
3720 		 * on early-pass buses during BUS_NEW_PASS().
3721 		 */
3722 		if (dl->pass > bus_current_pass)
3723 			continue;
3724 		DEVICE_IDENTIFY(dl->driver, dev);
3725 	}
3726 
3727 	return (0);
3728 }
3729 
3730 /**
3731  * @brief Helper function for implementing DEVICE_ATTACH()
3732  *
3733  * This function can be used to help implement the DEVICE_ATTACH() for
3734  * a bus. It calls device_probe_and_attach() for each of the device's
3735  * children.
3736  */
3737 int
3738 bus_generic_attach(device_t dev)
3739 {
3740 	device_t child;
3741 
3742 	TAILQ_FOREACH(child, &dev->children, link) {
3743 		device_probe_and_attach(child);
3744 	}
3745 
3746 	return (0);
3747 }
3748 
3749 /**
3750  * @brief Helper function for delaying attaching children
3751  *
3752  * Many buses can't run transactions on the bus which children need to probe and
3753  * attach until after interrupts and/or timers are running.  This function
3754  * delays their attach until interrupts and timers are enabled.
3755  */
3756 int
3757 bus_delayed_attach_children(device_t dev)
3758 {
3759 	/* Probe and attach the bus children when interrupts are available */
3760 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3761 
3762 	return (0);
3763 }
3764 
3765 /**
3766  * @brief Helper function for implementing DEVICE_DETACH()
3767  *
3768  * This function can be used to help implement the DEVICE_DETACH() for
3769  * a bus. It calls device_detach() for each of the device's
3770  * children.
3771  */
3772 int
3773 bus_generic_detach(device_t dev)
3774 {
3775 	device_t child;
3776 	int error;
3777 
3778 	if (dev->state != DS_ATTACHED)
3779 		return (EBUSY);
3780 
3781 	/*
3782 	 * Detach children in the reverse order.
3783 	 * See bus_generic_suspend for details.
3784 	 */
3785 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3786 		if ((error = device_detach(child)) != 0)
3787 			return (error);
3788 	}
3789 
3790 	return (0);
3791 }
3792 
3793 /**
3794  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3795  *
3796  * This function can be used to help implement the DEVICE_SHUTDOWN()
3797  * for a bus. It calls device_shutdown() for each of the device's
3798  * children.
3799  */
3800 int
3801 bus_generic_shutdown(device_t dev)
3802 {
3803 	device_t child;
3804 
3805 	/*
3806 	 * Shut down children in the reverse order.
3807 	 * See bus_generic_suspend for details.
3808 	 */
3809 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3810 		device_shutdown(child);
3811 	}
3812 
3813 	return (0);
3814 }
3815 
3816 /**
3817  * @brief Default function for suspending a child device.
3818  *
3819  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3820  */
3821 int
3822 bus_generic_suspend_child(device_t dev, device_t child)
3823 {
3824 	int	error;
3825 
3826 	error = DEVICE_SUSPEND(child);
3827 
3828 	if (error == 0)
3829 		child->flags |= DF_SUSPENDED;
3830 
3831 	return (error);
3832 }
3833 
3834 /**
3835  * @brief Default function for resuming a child device.
3836  *
3837  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3838  */
3839 int
3840 bus_generic_resume_child(device_t dev, device_t child)
3841 {
3842 	DEVICE_RESUME(child);
3843 	child->flags &= ~DF_SUSPENDED;
3844 
3845 	return (0);
3846 }
3847 
3848 /**
3849  * @brief Helper function for implementing DEVICE_SUSPEND()
3850  *
3851  * This function can be used to help implement the DEVICE_SUSPEND()
3852  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3853  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3854  * operation is aborted and any devices which were suspended are
3855  * resumed immediately by calling their DEVICE_RESUME() methods.
3856  */
3857 int
3858 bus_generic_suspend(device_t dev)
3859 {
3860 	int		error;
3861 	device_t	child;
3862 
3863 	/*
3864 	 * Suspend children in the reverse order.
3865 	 * For most buses all children are equal, so the order does not matter.
3866 	 * Other buses, such as acpi, carefully order their child devices to
3867 	 * express implicit dependencies between them.  For such buses it is
3868 	 * safer to bring down devices in the reverse order.
3869 	 */
3870 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3871 		error = BUS_SUSPEND_CHILD(dev, child);
3872 		if (error != 0) {
3873 			child = TAILQ_NEXT(child, link);
3874 			if (child != NULL) {
3875 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3876 					BUS_RESUME_CHILD(dev, child);
3877 			}
3878 			return (error);
3879 		}
3880 	}
3881 	return (0);
3882 }
3883 
3884 /**
3885  * @brief Helper function for implementing DEVICE_RESUME()
3886  *
3887  * This function can be used to help implement the DEVICE_RESUME() for
3888  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3889  */
3890 int
3891 bus_generic_resume(device_t dev)
3892 {
3893 	device_t	child;
3894 
3895 	TAILQ_FOREACH(child, &dev->children, link) {
3896 		BUS_RESUME_CHILD(dev, child);
3897 		/* if resume fails, there's nothing we can usefully do... */
3898 	}
3899 	return (0);
3900 }
3901 
3902 /**
3903  * @brief Helper function for implementing BUS_RESET_POST
3904  *
3905  * Bus can use this function to implement common operations of
3906  * re-attaching or resuming the children after the bus itself was
3907  * reset, and after restoring bus-unique state of children.
3908  *
3909  * @param dev	The bus
3910  * #param flags	DEVF_RESET_*
3911  */
3912 int
3913 bus_helper_reset_post(device_t dev, int flags)
3914 {
3915 	device_t child;
3916 	int error, error1;
3917 
3918 	error = 0;
3919 	TAILQ_FOREACH(child, &dev->children,link) {
3920 		BUS_RESET_POST(dev, child);
3921 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3922 		    device_probe_and_attach(child) :
3923 		    BUS_RESUME_CHILD(dev, child);
3924 		if (error == 0 && error1 != 0)
3925 			error = error1;
3926 	}
3927 	return (error);
3928 }
3929 
3930 static void
3931 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3932 {
3933 	child = TAILQ_NEXT(child, link);
3934 	if (child == NULL)
3935 		return;
3936 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3937 		BUS_RESET_POST(dev, child);
3938 		if ((flags & DEVF_RESET_DETACH) != 0)
3939 			device_probe_and_attach(child);
3940 		else
3941 			BUS_RESUME_CHILD(dev, child);
3942 	}
3943 }
3944 
3945 /**
3946  * @brief Helper function for implementing BUS_RESET_PREPARE
3947  *
3948  * Bus can use this function to implement common operations of
3949  * detaching or suspending the children before the bus itself is
3950  * reset, and then save bus-unique state of children that must
3951  * persists around reset.
3952  *
3953  * @param dev	The bus
3954  * #param flags	DEVF_RESET_*
3955  */
3956 int
3957 bus_helper_reset_prepare(device_t dev, int flags)
3958 {
3959 	device_t child;
3960 	int error;
3961 
3962 	if (dev->state != DS_ATTACHED)
3963 		return (EBUSY);
3964 
3965 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3966 		if ((flags & DEVF_RESET_DETACH) != 0) {
3967 			error = device_get_state(child) == DS_ATTACHED ?
3968 			    device_detach(child) : 0;
3969 		} else {
3970 			error = BUS_SUSPEND_CHILD(dev, child);
3971 		}
3972 		if (error == 0) {
3973 			error = BUS_RESET_PREPARE(dev, child);
3974 			if (error != 0) {
3975 				if ((flags & DEVF_RESET_DETACH) != 0)
3976 					device_probe_and_attach(child);
3977 				else
3978 					BUS_RESUME_CHILD(dev, child);
3979 			}
3980 		}
3981 		if (error != 0) {
3982 			bus_helper_reset_prepare_rollback(dev, child, flags);
3983 			return (error);
3984 		}
3985 	}
3986 	return (0);
3987 }
3988 
3989 /**
3990  * @brief Helper function for implementing BUS_PRINT_CHILD().
3991  *
3992  * This function prints the first part of the ascii representation of
3993  * @p child, including its name, unit and description (if any - see
3994  * device_set_desc()).
3995  *
3996  * @returns the number of characters printed
3997  */
3998 int
3999 bus_print_child_header(device_t dev, device_t child)
4000 {
4001 	int	retval = 0;
4002 
4003 	if (device_get_desc(child)) {
4004 		retval += device_printf(child, "<%s>", device_get_desc(child));
4005 	} else {
4006 		retval += printf("%s", device_get_nameunit(child));
4007 	}
4008 
4009 	return (retval);
4010 }
4011 
4012 /**
4013  * @brief Helper function for implementing BUS_PRINT_CHILD().
4014  *
4015  * This function prints the last part of the ascii representation of
4016  * @p child, which consists of the string @c " on " followed by the
4017  * name and unit of the @p dev.
4018  *
4019  * @returns the number of characters printed
4020  */
4021 int
4022 bus_print_child_footer(device_t dev, device_t child)
4023 {
4024 	return (printf(" on %s\n", device_get_nameunit(dev)));
4025 }
4026 
4027 /**
4028  * @brief Helper function for implementing BUS_PRINT_CHILD().
4029  *
4030  * This function prints out the VM domain for the given device.
4031  *
4032  * @returns the number of characters printed
4033  */
4034 int
4035 bus_print_child_domain(device_t dev, device_t child)
4036 {
4037 	int domain;
4038 
4039 	/* No domain? Don't print anything */
4040 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4041 		return (0);
4042 
4043 	return (printf(" numa-domain %d", domain));
4044 }
4045 
4046 /**
4047  * @brief Helper function for implementing BUS_PRINT_CHILD().
4048  *
4049  * This function simply calls bus_print_child_header() followed by
4050  * bus_print_child_footer().
4051  *
4052  * @returns the number of characters printed
4053  */
4054 int
4055 bus_generic_print_child(device_t dev, device_t child)
4056 {
4057 	int	retval = 0;
4058 
4059 	retval += bus_print_child_header(dev, child);
4060 	retval += bus_print_child_domain(dev, child);
4061 	retval += bus_print_child_footer(dev, child);
4062 
4063 	return (retval);
4064 }
4065 
4066 /**
4067  * @brief Stub function for implementing BUS_READ_IVAR().
4068  *
4069  * @returns ENOENT
4070  */
4071 int
4072 bus_generic_read_ivar(device_t dev, device_t child, int index,
4073     uintptr_t * result)
4074 {
4075 	return (ENOENT);
4076 }
4077 
4078 /**
4079  * @brief Stub function for implementing BUS_WRITE_IVAR().
4080  *
4081  * @returns ENOENT
4082  */
4083 int
4084 bus_generic_write_ivar(device_t dev, device_t child, int index,
4085     uintptr_t value)
4086 {
4087 	return (ENOENT);
4088 }
4089 
4090 /**
4091  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4092  *
4093  * @returns NULL
4094  */
4095 struct resource_list *
4096 bus_generic_get_resource_list(device_t dev, device_t child)
4097 {
4098 	return (NULL);
4099 }
4100 
4101 /**
4102  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4103  *
4104  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4105  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4106  * and then calls device_probe_and_attach() for each unattached child.
4107  */
4108 void
4109 bus_generic_driver_added(device_t dev, driver_t *driver)
4110 {
4111 	device_t child;
4112 
4113 	DEVICE_IDENTIFY(driver, dev);
4114 	TAILQ_FOREACH(child, &dev->children, link) {
4115 		if (child->state == DS_NOTPRESENT ||
4116 		    (child->flags & DF_REBID))
4117 			device_probe_and_attach(child);
4118 	}
4119 }
4120 
4121 /**
4122  * @brief Helper function for implementing BUS_NEW_PASS().
4123  *
4124  * This implementing of BUS_NEW_PASS() first calls the identify
4125  * routines for any drivers that probe at the current pass.  Then it
4126  * walks the list of devices for this bus.  If a device is already
4127  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4128  * device is not already attached, it attempts to attach a driver to
4129  * it.
4130  */
4131 void
4132 bus_generic_new_pass(device_t dev)
4133 {
4134 	driverlink_t dl;
4135 	devclass_t dc;
4136 	device_t child;
4137 
4138 	dc = dev->devclass;
4139 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4140 		if (dl->pass == bus_current_pass)
4141 			DEVICE_IDENTIFY(dl->driver, dev);
4142 	}
4143 	TAILQ_FOREACH(child, &dev->children, link) {
4144 		if (child->state >= DS_ATTACHED)
4145 			BUS_NEW_PASS(child);
4146 		else if (child->state == DS_NOTPRESENT)
4147 			device_probe_and_attach(child);
4148 	}
4149 }
4150 
4151 /**
4152  * @brief Helper function for implementing BUS_SETUP_INTR().
4153  *
4154  * This simple implementation of BUS_SETUP_INTR() simply calls the
4155  * BUS_SETUP_INTR() method of the parent of @p dev.
4156  */
4157 int
4158 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4159     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4160     void **cookiep)
4161 {
4162 	/* Propagate up the bus hierarchy until someone handles it. */
4163 	if (dev->parent)
4164 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4165 		    filter, intr, arg, cookiep));
4166 	return (EINVAL);
4167 }
4168 
4169 /**
4170  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4171  *
4172  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4173  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4174  */
4175 int
4176 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4177     void *cookie)
4178 {
4179 	/* Propagate up the bus hierarchy until someone handles it. */
4180 	if (dev->parent)
4181 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4182 	return (EINVAL);
4183 }
4184 
4185 /**
4186  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4187  *
4188  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4189  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4190  */
4191 int
4192 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4193 {
4194 	/* Propagate up the bus hierarchy until someone handles it. */
4195 	if (dev->parent)
4196 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4197 	return (EINVAL);
4198 }
4199 
4200 /**
4201  * @brief Helper function for implementing BUS_RESUME_INTR().
4202  *
4203  * This simple implementation of BUS_RESUME_INTR() simply calls the
4204  * BUS_RESUME_INTR() method of the parent of @p dev.
4205  */
4206 int
4207 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4208 {
4209 	/* Propagate up the bus hierarchy until someone handles it. */
4210 	if (dev->parent)
4211 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4212 	return (EINVAL);
4213 }
4214 
4215 /**
4216  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4217  *
4218  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4219  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4220  */
4221 int
4222 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4223     struct resource *r, rman_res_t start, rman_res_t end)
4224 {
4225 	/* Propagate up the bus hierarchy until someone handles it. */
4226 	if (dev->parent)
4227 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4228 		    end));
4229 	return (EINVAL);
4230 }
4231 
4232 /**
4233  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4234  *
4235  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4236  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4237  */
4238 struct resource *
4239 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4240     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4241 {
4242 	/* Propagate up the bus hierarchy until someone handles it. */
4243 	if (dev->parent)
4244 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4245 		    start, end, count, flags));
4246 	return (NULL);
4247 }
4248 
4249 /**
4250  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4251  *
4252  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4253  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4254  */
4255 int
4256 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4257     struct resource *r)
4258 {
4259 	/* Propagate up the bus hierarchy until someone handles it. */
4260 	if (dev->parent)
4261 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4262 		    r));
4263 	return (EINVAL);
4264 }
4265 
4266 /**
4267  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4268  *
4269  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4270  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4271  */
4272 int
4273 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4274     struct resource *r)
4275 {
4276 	/* Propagate up the bus hierarchy until someone handles it. */
4277 	if (dev->parent)
4278 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4279 		    r));
4280 	return (EINVAL);
4281 }
4282 
4283 /**
4284  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4285  *
4286  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4287  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4288  */
4289 int
4290 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4291     int rid, struct resource *r)
4292 {
4293 	/* Propagate up the bus hierarchy until someone handles it. */
4294 	if (dev->parent)
4295 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4296 		    r));
4297 	return (EINVAL);
4298 }
4299 
4300 /**
4301  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4302  *
4303  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4304  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4305  */
4306 int
4307 bus_generic_map_resource(device_t dev, device_t child, int type,
4308     struct resource *r, struct resource_map_request *args,
4309     struct resource_map *map)
4310 {
4311 	/* Propagate up the bus hierarchy until someone handles it. */
4312 	if (dev->parent)
4313 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4314 		    map));
4315 	return (EINVAL);
4316 }
4317 
4318 /**
4319  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4320  *
4321  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4322  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4323  */
4324 int
4325 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4326     struct resource *r, struct resource_map *map)
4327 {
4328 	/* Propagate up the bus hierarchy until someone handles it. */
4329 	if (dev->parent)
4330 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4331 	return (EINVAL);
4332 }
4333 
4334 /**
4335  * @brief Helper function for implementing BUS_BIND_INTR().
4336  *
4337  * This simple implementation of BUS_BIND_INTR() simply calls the
4338  * BUS_BIND_INTR() method of the parent of @p dev.
4339  */
4340 int
4341 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4342     int cpu)
4343 {
4344 	/* Propagate up the bus hierarchy until someone handles it. */
4345 	if (dev->parent)
4346 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4347 	return (EINVAL);
4348 }
4349 
4350 /**
4351  * @brief Helper function for implementing BUS_CONFIG_INTR().
4352  *
4353  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4354  * BUS_CONFIG_INTR() method of the parent of @p dev.
4355  */
4356 int
4357 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4358     enum intr_polarity pol)
4359 {
4360 	/* Propagate up the bus hierarchy until someone handles it. */
4361 	if (dev->parent)
4362 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4363 	return (EINVAL);
4364 }
4365 
4366 /**
4367  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4368  *
4369  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4370  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4371  */
4372 int
4373 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4374     void *cookie, const char *descr)
4375 {
4376 	/* Propagate up the bus hierarchy until someone handles it. */
4377 	if (dev->parent)
4378 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4379 		    descr));
4380 	return (EINVAL);
4381 }
4382 
4383 /**
4384  * @brief Helper function for implementing BUS_GET_CPUS().
4385  *
4386  * This simple implementation of BUS_GET_CPUS() simply calls the
4387  * BUS_GET_CPUS() method of the parent of @p dev.
4388  */
4389 int
4390 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4391     size_t setsize, cpuset_t *cpuset)
4392 {
4393 	/* Propagate up the bus hierarchy until someone handles it. */
4394 	if (dev->parent != NULL)
4395 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4396 	return (EINVAL);
4397 }
4398 
4399 /**
4400  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4401  *
4402  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4403  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4404  */
4405 bus_dma_tag_t
4406 bus_generic_get_dma_tag(device_t dev, device_t child)
4407 {
4408 	/* Propagate up the bus hierarchy until someone handles it. */
4409 	if (dev->parent != NULL)
4410 		return (BUS_GET_DMA_TAG(dev->parent, child));
4411 	return (NULL);
4412 }
4413 
4414 /**
4415  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4416  *
4417  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4418  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4419  */
4420 bus_space_tag_t
4421 bus_generic_get_bus_tag(device_t dev, device_t child)
4422 {
4423 	/* Propagate up the bus hierarchy until someone handles it. */
4424 	if (dev->parent != NULL)
4425 		return (BUS_GET_BUS_TAG(dev->parent, child));
4426 	return ((bus_space_tag_t)0);
4427 }
4428 
4429 /**
4430  * @brief Helper function for implementing BUS_GET_RESOURCE().
4431  *
4432  * This implementation of BUS_GET_RESOURCE() uses the
4433  * resource_list_find() function to do most of the work. It calls
4434  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4435  * search.
4436  */
4437 int
4438 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4439     rman_res_t *startp, rman_res_t *countp)
4440 {
4441 	struct resource_list *		rl = NULL;
4442 	struct resource_list_entry *	rle = NULL;
4443 
4444 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4445 	if (!rl)
4446 		return (EINVAL);
4447 
4448 	rle = resource_list_find(rl, type, rid);
4449 	if (!rle)
4450 		return (ENOENT);
4451 
4452 	if (startp)
4453 		*startp = rle->start;
4454 	if (countp)
4455 		*countp = rle->count;
4456 
4457 	return (0);
4458 }
4459 
4460 /**
4461  * @brief Helper function for implementing BUS_SET_RESOURCE().
4462  *
4463  * This implementation of BUS_SET_RESOURCE() uses the
4464  * resource_list_add() function to do most of the work. It calls
4465  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4466  * edit.
4467  */
4468 int
4469 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4470     rman_res_t start, rman_res_t count)
4471 {
4472 	struct resource_list *		rl = NULL;
4473 
4474 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4475 	if (!rl)
4476 		return (EINVAL);
4477 
4478 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4479 
4480 	return (0);
4481 }
4482 
4483 /**
4484  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4485  *
4486  * This implementation of BUS_DELETE_RESOURCE() uses the
4487  * resource_list_delete() function to do most of the work. It calls
4488  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4489  * edit.
4490  */
4491 void
4492 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4493 {
4494 	struct resource_list *		rl = NULL;
4495 
4496 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4497 	if (!rl)
4498 		return;
4499 
4500 	resource_list_delete(rl, type, rid);
4501 
4502 	return;
4503 }
4504 
4505 /**
4506  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4507  *
4508  * This implementation of BUS_RELEASE_RESOURCE() uses the
4509  * resource_list_release() function to do most of the work. It calls
4510  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4511  */
4512 int
4513 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4514     int rid, struct resource *r)
4515 {
4516 	struct resource_list *		rl = NULL;
4517 
4518 	if (device_get_parent(child) != dev)
4519 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4520 		    type, rid, r));
4521 
4522 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4523 	if (!rl)
4524 		return (EINVAL);
4525 
4526 	return (resource_list_release(rl, dev, child, type, rid, r));
4527 }
4528 
4529 /**
4530  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4531  *
4532  * This implementation of BUS_ALLOC_RESOURCE() uses the
4533  * resource_list_alloc() function to do most of the work. It calls
4534  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4535  */
4536 struct resource *
4537 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4538     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4539 {
4540 	struct resource_list *		rl = NULL;
4541 
4542 	if (device_get_parent(child) != dev)
4543 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4544 		    type, rid, start, end, count, flags));
4545 
4546 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4547 	if (!rl)
4548 		return (NULL);
4549 
4550 	return (resource_list_alloc(rl, dev, child, type, rid,
4551 	    start, end, count, flags));
4552 }
4553 
4554 /**
4555  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4556  *
4557  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4558  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4559  */
4560 int
4561 bus_generic_child_present(device_t dev, device_t child)
4562 {
4563 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4564 }
4565 
4566 int
4567 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4568 {
4569 	if (dev->parent)
4570 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4571 
4572 	return (ENOENT);
4573 }
4574 
4575 /**
4576  * @brief Helper function for implementing BUS_RESCAN().
4577  *
4578  * This null implementation of BUS_RESCAN() always fails to indicate
4579  * the bus does not support rescanning.
4580  */
4581 int
4582 bus_null_rescan(device_t dev)
4583 {
4584 	return (ENXIO);
4585 }
4586 
4587 /*
4588  * Some convenience functions to make it easier for drivers to use the
4589  * resource-management functions.  All these really do is hide the
4590  * indirection through the parent's method table, making for slightly
4591  * less-wordy code.  In the future, it might make sense for this code
4592  * to maintain some sort of a list of resources allocated by each device.
4593  */
4594 
4595 int
4596 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4597     struct resource **res)
4598 {
4599 	int i;
4600 
4601 	for (i = 0; rs[i].type != -1; i++)
4602 		res[i] = NULL;
4603 	for (i = 0; rs[i].type != -1; i++) {
4604 		res[i] = bus_alloc_resource_any(dev,
4605 		    rs[i].type, &rs[i].rid, rs[i].flags);
4606 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4607 			bus_release_resources(dev, rs, res);
4608 			return (ENXIO);
4609 		}
4610 	}
4611 	return (0);
4612 }
4613 
4614 void
4615 bus_release_resources(device_t dev, const struct resource_spec *rs,
4616     struct resource **res)
4617 {
4618 	int i;
4619 
4620 	for (i = 0; rs[i].type != -1; i++)
4621 		if (res[i] != NULL) {
4622 			bus_release_resource(
4623 			    dev, rs[i].type, rs[i].rid, res[i]);
4624 			res[i] = NULL;
4625 		}
4626 }
4627 
4628 /**
4629  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4630  *
4631  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4632  * parent of @p dev.
4633  */
4634 struct resource *
4635 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4636     rman_res_t end, rman_res_t count, u_int flags)
4637 {
4638 	struct resource *res;
4639 
4640 	if (dev->parent == NULL)
4641 		return (NULL);
4642 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4643 	    count, flags);
4644 	return (res);
4645 }
4646 
4647 /**
4648  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4649  *
4650  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4651  * parent of @p dev.
4652  */
4653 int
4654 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4655     rman_res_t end)
4656 {
4657 	if (dev->parent == NULL)
4658 		return (EINVAL);
4659 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4660 }
4661 
4662 /**
4663  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4664  *
4665  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4666  * parent of @p dev.
4667  */
4668 int
4669 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4670 {
4671 	if (dev->parent == NULL)
4672 		return (EINVAL);
4673 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4674 }
4675 
4676 /**
4677  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4678  *
4679  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4680  * parent of @p dev.
4681  */
4682 int
4683 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4684 {
4685 	if (dev->parent == NULL)
4686 		return (EINVAL);
4687 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4688 }
4689 
4690 /**
4691  * @brief Wrapper function for BUS_MAP_RESOURCE().
4692  *
4693  * This function simply calls the BUS_MAP_RESOURCE() method of the
4694  * parent of @p dev.
4695  */
4696 int
4697 bus_map_resource(device_t dev, int type, struct resource *r,
4698     struct resource_map_request *args, struct resource_map *map)
4699 {
4700 	if (dev->parent == NULL)
4701 		return (EINVAL);
4702 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4703 }
4704 
4705 /**
4706  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4707  *
4708  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4709  * parent of @p dev.
4710  */
4711 int
4712 bus_unmap_resource(device_t dev, int type, struct resource *r,
4713     struct resource_map *map)
4714 {
4715 	if (dev->parent == NULL)
4716 		return (EINVAL);
4717 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4718 }
4719 
4720 /**
4721  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4722  *
4723  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4724  * parent of @p dev.
4725  */
4726 int
4727 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4728 {
4729 	int rv;
4730 
4731 	if (dev->parent == NULL)
4732 		return (EINVAL);
4733 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4734 	return (rv);
4735 }
4736 
4737 /**
4738  * @brief Wrapper function for BUS_SETUP_INTR().
4739  *
4740  * This function simply calls the BUS_SETUP_INTR() method of the
4741  * parent of @p dev.
4742  */
4743 int
4744 bus_setup_intr(device_t dev, struct resource *r, int flags,
4745     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4746 {
4747 	int error;
4748 
4749 	if (dev->parent == NULL)
4750 		return (EINVAL);
4751 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4752 	    arg, cookiep);
4753 	if (error != 0)
4754 		return (error);
4755 	if (handler != NULL && !(flags & INTR_MPSAFE))
4756 		device_printf(dev, "[GIANT-LOCKED]\n");
4757 	return (0);
4758 }
4759 
4760 /**
4761  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4762  *
4763  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4764  * parent of @p dev.
4765  */
4766 int
4767 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4768 {
4769 	if (dev->parent == NULL)
4770 		return (EINVAL);
4771 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4772 }
4773 
4774 /**
4775  * @brief Wrapper function for BUS_SUSPEND_INTR().
4776  *
4777  * This function simply calls the BUS_SUSPEND_INTR() method of the
4778  * parent of @p dev.
4779  */
4780 int
4781 bus_suspend_intr(device_t dev, struct resource *r)
4782 {
4783 	if (dev->parent == NULL)
4784 		return (EINVAL);
4785 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4786 }
4787 
4788 /**
4789  * @brief Wrapper function for BUS_RESUME_INTR().
4790  *
4791  * This function simply calls the BUS_RESUME_INTR() method of the
4792  * parent of @p dev.
4793  */
4794 int
4795 bus_resume_intr(device_t dev, struct resource *r)
4796 {
4797 	if (dev->parent == NULL)
4798 		return (EINVAL);
4799 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4800 }
4801 
4802 /**
4803  * @brief Wrapper function for BUS_BIND_INTR().
4804  *
4805  * This function simply calls the BUS_BIND_INTR() method of the
4806  * parent of @p dev.
4807  */
4808 int
4809 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4810 {
4811 	if (dev->parent == NULL)
4812 		return (EINVAL);
4813 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4814 }
4815 
4816 /**
4817  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4818  *
4819  * This function first formats the requested description into a
4820  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4821  * the parent of @p dev.
4822  */
4823 int
4824 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4825     const char *fmt, ...)
4826 {
4827 	va_list ap;
4828 	char descr[MAXCOMLEN + 1];
4829 
4830 	if (dev->parent == NULL)
4831 		return (EINVAL);
4832 	va_start(ap, fmt);
4833 	vsnprintf(descr, sizeof(descr), fmt, ap);
4834 	va_end(ap);
4835 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4836 }
4837 
4838 /**
4839  * @brief Wrapper function for BUS_SET_RESOURCE().
4840  *
4841  * This function simply calls the BUS_SET_RESOURCE() method of the
4842  * parent of @p dev.
4843  */
4844 int
4845 bus_set_resource(device_t dev, int type, int rid,
4846     rman_res_t start, rman_res_t count)
4847 {
4848 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4849 	    start, count));
4850 }
4851 
4852 /**
4853  * @brief Wrapper function for BUS_GET_RESOURCE().
4854  *
4855  * This function simply calls the BUS_GET_RESOURCE() method of the
4856  * parent of @p dev.
4857  */
4858 int
4859 bus_get_resource(device_t dev, int type, int rid,
4860     rman_res_t *startp, rman_res_t *countp)
4861 {
4862 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4863 	    startp, countp));
4864 }
4865 
4866 /**
4867  * @brief Wrapper function for BUS_GET_RESOURCE().
4868  *
4869  * This function simply calls the BUS_GET_RESOURCE() method of the
4870  * parent of @p dev and returns the start value.
4871  */
4872 rman_res_t
4873 bus_get_resource_start(device_t dev, int type, int rid)
4874 {
4875 	rman_res_t start;
4876 	rman_res_t count;
4877 	int error;
4878 
4879 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4880 	    &start, &count);
4881 	if (error)
4882 		return (0);
4883 	return (start);
4884 }
4885 
4886 /**
4887  * @brief Wrapper function for BUS_GET_RESOURCE().
4888  *
4889  * This function simply calls the BUS_GET_RESOURCE() method of the
4890  * parent of @p dev and returns the count value.
4891  */
4892 rman_res_t
4893 bus_get_resource_count(device_t dev, int type, int rid)
4894 {
4895 	rman_res_t start;
4896 	rman_res_t count;
4897 	int error;
4898 
4899 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4900 	    &start, &count);
4901 	if (error)
4902 		return (0);
4903 	return (count);
4904 }
4905 
4906 /**
4907  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4908  *
4909  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4910  * parent of @p dev.
4911  */
4912 void
4913 bus_delete_resource(device_t dev, int type, int rid)
4914 {
4915 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4916 }
4917 
4918 /**
4919  * @brief Wrapper function for BUS_CHILD_PRESENT().
4920  *
4921  * This function simply calls the BUS_CHILD_PRESENT() method of the
4922  * parent of @p dev.
4923  */
4924 int
4925 bus_child_present(device_t child)
4926 {
4927 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4928 }
4929 
4930 /**
4931  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4932  *
4933  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4934  * parent of @p dev.
4935  */
4936 int
4937 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4938 {
4939 	device_t parent;
4940 
4941 	parent = device_get_parent(child);
4942 	if (parent == NULL) {
4943 		*buf = '\0';
4944 		return (0);
4945 	}
4946 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4947 }
4948 
4949 /**
4950  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4951  *
4952  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4953  * parent of @p dev.
4954  */
4955 int
4956 bus_child_location_str(device_t child, char *buf, size_t buflen)
4957 {
4958 	device_t parent;
4959 
4960 	parent = device_get_parent(child);
4961 	if (parent == NULL) {
4962 		*buf = '\0';
4963 		return (0);
4964 	}
4965 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4966 }
4967 
4968 /**
4969  * @brief Wrapper function for BUS_GET_CPUS().
4970  *
4971  * This function simply calls the BUS_GET_CPUS() method of the
4972  * parent of @p dev.
4973  */
4974 int
4975 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
4976 {
4977 	device_t parent;
4978 
4979 	parent = device_get_parent(dev);
4980 	if (parent == NULL)
4981 		return (EINVAL);
4982 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
4983 }
4984 
4985 /**
4986  * @brief Wrapper function for BUS_GET_DMA_TAG().
4987  *
4988  * This function simply calls the BUS_GET_DMA_TAG() method of the
4989  * parent of @p dev.
4990  */
4991 bus_dma_tag_t
4992 bus_get_dma_tag(device_t dev)
4993 {
4994 	device_t parent;
4995 
4996 	parent = device_get_parent(dev);
4997 	if (parent == NULL)
4998 		return (NULL);
4999 	return (BUS_GET_DMA_TAG(parent, dev));
5000 }
5001 
5002 /**
5003  * @brief Wrapper function for BUS_GET_BUS_TAG().
5004  *
5005  * This function simply calls the BUS_GET_BUS_TAG() method of the
5006  * parent of @p dev.
5007  */
5008 bus_space_tag_t
5009 bus_get_bus_tag(device_t dev)
5010 {
5011 	device_t parent;
5012 
5013 	parent = device_get_parent(dev);
5014 	if (parent == NULL)
5015 		return ((bus_space_tag_t)0);
5016 	return (BUS_GET_BUS_TAG(parent, dev));
5017 }
5018 
5019 /**
5020  * @brief Wrapper function for BUS_GET_DOMAIN().
5021  *
5022  * This function simply calls the BUS_GET_DOMAIN() method of the
5023  * parent of @p dev.
5024  */
5025 int
5026 bus_get_domain(device_t dev, int *domain)
5027 {
5028 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5029 }
5030 
5031 /* Resume all devices and then notify userland that we're up again. */
5032 static int
5033 root_resume(device_t dev)
5034 {
5035 	int error;
5036 
5037 	error = bus_generic_resume(dev);
5038 	if (error == 0)
5039 		devctl_notify("kern", "power", "resume", NULL);
5040 	return (error);
5041 }
5042 
5043 static int
5044 root_print_child(device_t dev, device_t child)
5045 {
5046 	int	retval = 0;
5047 
5048 	retval += bus_print_child_header(dev, child);
5049 	retval += printf("\n");
5050 
5051 	return (retval);
5052 }
5053 
5054 static int
5055 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5056     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5057 {
5058 	/*
5059 	 * If an interrupt mapping gets to here something bad has happened.
5060 	 */
5061 	panic("root_setup_intr");
5062 }
5063 
5064 /*
5065  * If we get here, assume that the device is permanent and really is
5066  * present in the system.  Removable bus drivers are expected to intercept
5067  * this call long before it gets here.  We return -1 so that drivers that
5068  * really care can check vs -1 or some ERRNO returned higher in the food
5069  * chain.
5070  */
5071 static int
5072 root_child_present(device_t dev, device_t child)
5073 {
5074 	return (-1);
5075 }
5076 
5077 static int
5078 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5079     cpuset_t *cpuset)
5080 {
5081 	switch (op) {
5082 	case INTR_CPUS:
5083 		/* Default to returning the set of all CPUs. */
5084 		if (setsize != sizeof(cpuset_t))
5085 			return (EINVAL);
5086 		*cpuset = all_cpus;
5087 		return (0);
5088 	default:
5089 		return (EINVAL);
5090 	}
5091 }
5092 
5093 static kobj_method_t root_methods[] = {
5094 	/* Device interface */
5095 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5096 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5097 	KOBJMETHOD(device_resume,	root_resume),
5098 
5099 	/* Bus interface */
5100 	KOBJMETHOD(bus_print_child,	root_print_child),
5101 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5102 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5103 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5104 	KOBJMETHOD(bus_child_present,	root_child_present),
5105 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5106 
5107 	KOBJMETHOD_END
5108 };
5109 
5110 static driver_t root_driver = {
5111 	"root",
5112 	root_methods,
5113 	1,			/* no softc */
5114 };
5115 
5116 device_t	root_bus;
5117 devclass_t	root_devclass;
5118 
5119 static int
5120 root_bus_module_handler(module_t mod, int what, void* arg)
5121 {
5122 	switch (what) {
5123 	case MOD_LOAD:
5124 		TAILQ_INIT(&bus_data_devices);
5125 		kobj_class_compile((kobj_class_t) &root_driver);
5126 		root_bus = make_device(NULL, "root", 0);
5127 		root_bus->desc = "System root bus";
5128 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5129 		root_bus->driver = &root_driver;
5130 		root_bus->state = DS_ATTACHED;
5131 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5132 		devinit();
5133 		return (0);
5134 
5135 	case MOD_SHUTDOWN:
5136 		device_shutdown(root_bus);
5137 		return (0);
5138 	default:
5139 		return (EOPNOTSUPP);
5140 	}
5141 
5142 	return (0);
5143 }
5144 
5145 static moduledata_t root_bus_mod = {
5146 	"rootbus",
5147 	root_bus_module_handler,
5148 	NULL
5149 };
5150 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5151 
5152 /**
5153  * @brief Automatically configure devices
5154  *
5155  * This function begins the autoconfiguration process by calling
5156  * device_probe_and_attach() for each child of the @c root0 device.
5157  */
5158 void
5159 root_bus_configure(void)
5160 {
5161 	PDEBUG(("."));
5162 
5163 	/* Eventually this will be split up, but this is sufficient for now. */
5164 	bus_set_pass(BUS_PASS_DEFAULT);
5165 }
5166 
5167 /**
5168  * @brief Module handler for registering device drivers
5169  *
5170  * This module handler is used to automatically register device
5171  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5172  * devclass_add_driver() for the driver described by the
5173  * driver_module_data structure pointed to by @p arg
5174  */
5175 int
5176 driver_module_handler(module_t mod, int what, void *arg)
5177 {
5178 	struct driver_module_data *dmd;
5179 	devclass_t bus_devclass;
5180 	kobj_class_t driver;
5181 	int error, pass;
5182 
5183 	dmd = (struct driver_module_data *)arg;
5184 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5185 	error = 0;
5186 
5187 	switch (what) {
5188 	case MOD_LOAD:
5189 		if (dmd->dmd_chainevh)
5190 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5191 
5192 		pass = dmd->dmd_pass;
5193 		driver = dmd->dmd_driver;
5194 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5195 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5196 		error = devclass_add_driver(bus_devclass, driver, pass,
5197 		    dmd->dmd_devclass);
5198 		break;
5199 
5200 	case MOD_UNLOAD:
5201 		PDEBUG(("Unloading module: driver %s from bus %s",
5202 		    DRIVERNAME(dmd->dmd_driver),
5203 		    dmd->dmd_busname));
5204 		error = devclass_delete_driver(bus_devclass,
5205 		    dmd->dmd_driver);
5206 
5207 		if (!error && dmd->dmd_chainevh)
5208 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5209 		break;
5210 	case MOD_QUIESCE:
5211 		PDEBUG(("Quiesce module: driver %s from bus %s",
5212 		    DRIVERNAME(dmd->dmd_driver),
5213 		    dmd->dmd_busname));
5214 		error = devclass_quiesce_driver(bus_devclass,
5215 		    dmd->dmd_driver);
5216 
5217 		if (!error && dmd->dmd_chainevh)
5218 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5219 		break;
5220 	default:
5221 		error = EOPNOTSUPP;
5222 		break;
5223 	}
5224 
5225 	return (error);
5226 }
5227 
5228 /**
5229  * @brief Enumerate all hinted devices for this bus.
5230  *
5231  * Walks through the hints for this bus and calls the bus_hinted_child
5232  * routine for each one it fines.  It searches first for the specific
5233  * bus that's being probed for hinted children (eg isa0), and then for
5234  * generic children (eg isa).
5235  *
5236  * @param	dev	bus device to enumerate
5237  */
5238 void
5239 bus_enumerate_hinted_children(device_t bus)
5240 {
5241 	int i;
5242 	const char *dname, *busname;
5243 	int dunit;
5244 
5245 	/*
5246 	 * enumerate all devices on the specific bus
5247 	 */
5248 	busname = device_get_nameunit(bus);
5249 	i = 0;
5250 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5251 		BUS_HINTED_CHILD(bus, dname, dunit);
5252 
5253 	/*
5254 	 * and all the generic ones.
5255 	 */
5256 	busname = device_get_name(bus);
5257 	i = 0;
5258 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5259 		BUS_HINTED_CHILD(bus, dname, dunit);
5260 }
5261 
5262 #ifdef BUS_DEBUG
5263 
5264 /* the _short versions avoid iteration by not calling anything that prints
5265  * more than oneliners. I love oneliners.
5266  */
5267 
5268 static void
5269 print_device_short(device_t dev, int indent)
5270 {
5271 	if (!dev)
5272 		return;
5273 
5274 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5275 	    dev->unit, dev->desc,
5276 	    (dev->parent? "":"no "),
5277 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5278 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5279 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5280 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5281 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5282 	    (dev->flags&DF_REBID? "rebiddable,":""),
5283 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5284 	    (dev->ivars? "":"no "),
5285 	    (dev->softc? "":"no "),
5286 	    dev->busy));
5287 }
5288 
5289 static void
5290 print_device(device_t dev, int indent)
5291 {
5292 	if (!dev)
5293 		return;
5294 
5295 	print_device_short(dev, indent);
5296 
5297 	indentprintf(("Parent:\n"));
5298 	print_device_short(dev->parent, indent+1);
5299 	indentprintf(("Driver:\n"));
5300 	print_driver_short(dev->driver, indent+1);
5301 	indentprintf(("Devclass:\n"));
5302 	print_devclass_short(dev->devclass, indent+1);
5303 }
5304 
5305 void
5306 print_device_tree_short(device_t dev, int indent)
5307 /* print the device and all its children (indented) */
5308 {
5309 	device_t child;
5310 
5311 	if (!dev)
5312 		return;
5313 
5314 	print_device_short(dev, indent);
5315 
5316 	TAILQ_FOREACH(child, &dev->children, link) {
5317 		print_device_tree_short(child, indent+1);
5318 	}
5319 }
5320 
5321 void
5322 print_device_tree(device_t dev, int indent)
5323 /* print the device and all its children (indented) */
5324 {
5325 	device_t child;
5326 
5327 	if (!dev)
5328 		return;
5329 
5330 	print_device(dev, indent);
5331 
5332 	TAILQ_FOREACH(child, &dev->children, link) {
5333 		print_device_tree(child, indent+1);
5334 	}
5335 }
5336 
5337 static void
5338 print_driver_short(driver_t *driver, int indent)
5339 {
5340 	if (!driver)
5341 		return;
5342 
5343 	indentprintf(("driver %s: softc size = %zd\n",
5344 	    driver->name, driver->size));
5345 }
5346 
5347 static void
5348 print_driver(driver_t *driver, int indent)
5349 {
5350 	if (!driver)
5351 		return;
5352 
5353 	print_driver_short(driver, indent);
5354 }
5355 
5356 static void
5357 print_driver_list(driver_list_t drivers, int indent)
5358 {
5359 	driverlink_t driver;
5360 
5361 	TAILQ_FOREACH(driver, &drivers, link) {
5362 		print_driver(driver->driver, indent);
5363 	}
5364 }
5365 
5366 static void
5367 print_devclass_short(devclass_t dc, int indent)
5368 {
5369 	if ( !dc )
5370 		return;
5371 
5372 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5373 }
5374 
5375 static void
5376 print_devclass(devclass_t dc, int indent)
5377 {
5378 	int i;
5379 
5380 	if ( !dc )
5381 		return;
5382 
5383 	print_devclass_short(dc, indent);
5384 	indentprintf(("Drivers:\n"));
5385 	print_driver_list(dc->drivers, indent+1);
5386 
5387 	indentprintf(("Devices:\n"));
5388 	for (i = 0; i < dc->maxunit; i++)
5389 		if (dc->devices[i])
5390 			print_device(dc->devices[i], indent+1);
5391 }
5392 
5393 void
5394 print_devclass_list_short(void)
5395 {
5396 	devclass_t dc;
5397 
5398 	printf("Short listing of devclasses, drivers & devices:\n");
5399 	TAILQ_FOREACH(dc, &devclasses, link) {
5400 		print_devclass_short(dc, 0);
5401 	}
5402 }
5403 
5404 void
5405 print_devclass_list(void)
5406 {
5407 	devclass_t dc;
5408 
5409 	printf("Full listing of devclasses, drivers & devices:\n");
5410 	TAILQ_FOREACH(dc, &devclasses, link) {
5411 		print_devclass(dc, 0);
5412 	}
5413 }
5414 
5415 #endif
5416 
5417 /*
5418  * User-space access to the device tree.
5419  *
5420  * We implement a small set of nodes:
5421  *
5422  * hw.bus			Single integer read method to obtain the
5423  *				current generation count.
5424  * hw.bus.devices		Reads the entire device tree in flat space.
5425  * hw.bus.rman			Resource manager interface
5426  *
5427  * We might like to add the ability to scan devclasses and/or drivers to
5428  * determine what else is currently loaded/available.
5429  */
5430 
5431 static int
5432 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5433 {
5434 	struct u_businfo	ubus;
5435 
5436 	ubus.ub_version = BUS_USER_VERSION;
5437 	ubus.ub_generation = bus_data_generation;
5438 
5439 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5440 }
5441 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5442     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5443     "bus-related data");
5444 
5445 static int
5446 sysctl_devices(SYSCTL_HANDLER_ARGS)
5447 {
5448 	int			*name = (int *)arg1;
5449 	u_int			namelen = arg2;
5450 	int			index;
5451 	device_t		dev;
5452 	struct u_device		*udev;
5453 	int			error;
5454 	char			*walker, *ep;
5455 
5456 	if (namelen != 2)
5457 		return (EINVAL);
5458 
5459 	if (bus_data_generation_check(name[0]))
5460 		return (EINVAL);
5461 
5462 	index = name[1];
5463 
5464 	/*
5465 	 * Scan the list of devices, looking for the requested index.
5466 	 */
5467 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5468 		if (index-- == 0)
5469 			break;
5470 	}
5471 	if (dev == NULL)
5472 		return (ENOENT);
5473 
5474 	/*
5475 	 * Populate the return item, careful not to overflow the buffer.
5476 	 */
5477 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5478 	if (udev == NULL)
5479 		return (ENOMEM);
5480 	udev->dv_handle = (uintptr_t)dev;
5481 	udev->dv_parent = (uintptr_t)dev->parent;
5482 	udev->dv_devflags = dev->devflags;
5483 	udev->dv_flags = dev->flags;
5484 	udev->dv_state = dev->state;
5485 	walker = udev->dv_fields;
5486 	ep = walker + sizeof(udev->dv_fields);
5487 #define CP(src)						\
5488 	if ((src) == NULL)				\
5489 		*walker++ = '\0';			\
5490 	else {						\
5491 		strlcpy(walker, (src), ep - walker);	\
5492 		walker += strlen(walker) + 1;		\
5493 	}						\
5494 	if (walker >= ep)				\
5495 		break;
5496 
5497 	do {
5498 		CP(dev->nameunit);
5499 		CP(dev->desc);
5500 		CP(dev->driver != NULL ? dev->driver->name : NULL);
5501 		bus_child_pnpinfo_str(dev, walker, ep - walker);
5502 		walker += strlen(walker) + 1;
5503 		if (walker >= ep)
5504 			break;
5505 		bus_child_location_str(dev, walker, ep - walker);
5506 		walker += strlen(walker) + 1;
5507 		if (walker >= ep)
5508 			break;
5509 		*walker++ = '\0';
5510 	} while (0);
5511 #undef CP
5512 	error = SYSCTL_OUT(req, udev, sizeof(*udev));
5513 	free(udev, M_BUS);
5514 	return (error);
5515 }
5516 
5517 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5518     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5519     "system device tree");
5520 
5521 int
5522 bus_data_generation_check(int generation)
5523 {
5524 	if (generation != bus_data_generation)
5525 		return (1);
5526 
5527 	/* XXX generate optimised lists here? */
5528 	return (0);
5529 }
5530 
5531 void
5532 bus_data_generation_update(void)
5533 {
5534 	atomic_add_int(&bus_data_generation, 1);
5535 }
5536 
5537 int
5538 bus_free_resource(device_t dev, int type, struct resource *r)
5539 {
5540 	if (r == NULL)
5541 		return (0);
5542 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5543 }
5544 
5545 device_t
5546 device_lookup_by_name(const char *name)
5547 {
5548 	device_t dev;
5549 
5550 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5551 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5552 			return (dev);
5553 	}
5554 	return (NULL);
5555 }
5556 
5557 /*
5558  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5559  * implicit semantics on open, so it could not be reused for this.
5560  * Another option would be to call this /dev/bus?
5561  */
5562 static int
5563 find_device(struct devreq *req, device_t *devp)
5564 {
5565 	device_t dev;
5566 
5567 	/*
5568 	 * First, ensure that the name is nul terminated.
5569 	 */
5570 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5571 		return (EINVAL);
5572 
5573 	/*
5574 	 * Second, try to find an attached device whose name matches
5575 	 * 'name'.
5576 	 */
5577 	dev = device_lookup_by_name(req->dr_name);
5578 	if (dev != NULL) {
5579 		*devp = dev;
5580 		return (0);
5581 	}
5582 
5583 	/* Finally, give device enumerators a chance. */
5584 	dev = NULL;
5585 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5586 	if (dev == NULL)
5587 		return (ENOENT);
5588 	*devp = dev;
5589 	return (0);
5590 }
5591 
5592 static bool
5593 driver_exists(device_t bus, const char *driver)
5594 {
5595 	devclass_t dc;
5596 
5597 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5598 		if (devclass_find_driver_internal(dc, driver) != NULL)
5599 			return (true);
5600 	}
5601 	return (false);
5602 }
5603 
5604 static void
5605 device_gen_nomatch(device_t dev)
5606 {
5607 	device_t child;
5608 
5609 	if (dev->flags & DF_NEEDNOMATCH &&
5610 	    dev->state == DS_NOTPRESENT) {
5611 		BUS_PROBE_NOMATCH(dev->parent, dev);
5612 		devnomatch(dev);
5613 		dev->flags |= DF_DONENOMATCH;
5614 	}
5615 	dev->flags &= ~DF_NEEDNOMATCH;
5616 	TAILQ_FOREACH(child, &dev->children, link) {
5617 		device_gen_nomatch(child);
5618 	}
5619 }
5620 
5621 static void
5622 device_do_deferred_actions(void)
5623 {
5624 	devclass_t dc;
5625 	driverlink_t dl;
5626 
5627 	/*
5628 	 * Walk through the devclasses to find all the drivers we've tagged as
5629 	 * deferred during the freeze and call the driver added routines. They
5630 	 * have already been added to the lists in the background, so the driver
5631 	 * added routines that trigger a probe will have all the right bidders
5632 	 * for the probe auction.
5633 	 */
5634 	TAILQ_FOREACH(dc, &devclasses, link) {
5635 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5636 			if (dl->flags & DL_DEFERRED_PROBE) {
5637 				devclass_driver_added(dc, dl->driver);
5638 				dl->flags &= ~DL_DEFERRED_PROBE;
5639 			}
5640 		}
5641 	}
5642 
5643 	/*
5644 	 * We also defer no-match events during a freeze. Walk the tree and
5645 	 * generate all the pent-up events that are still relevant.
5646 	 */
5647 	device_gen_nomatch(root_bus);
5648 	bus_data_generation_update();
5649 }
5650 
5651 static int
5652 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5653     struct thread *td)
5654 {
5655 	struct devreq *req;
5656 	device_t dev;
5657 	int error, old;
5658 
5659 	/* Locate the device to control. */
5660 	mtx_lock(&Giant);
5661 	req = (struct devreq *)data;
5662 	switch (cmd) {
5663 	case DEV_ATTACH:
5664 	case DEV_DETACH:
5665 	case DEV_ENABLE:
5666 	case DEV_DISABLE:
5667 	case DEV_SUSPEND:
5668 	case DEV_RESUME:
5669 	case DEV_SET_DRIVER:
5670 	case DEV_CLEAR_DRIVER:
5671 	case DEV_RESCAN:
5672 	case DEV_DELETE:
5673 	case DEV_RESET:
5674 		error = priv_check(td, PRIV_DRIVER);
5675 		if (error == 0)
5676 			error = find_device(req, &dev);
5677 		break;
5678 	case DEV_FREEZE:
5679 	case DEV_THAW:
5680 		error = priv_check(td, PRIV_DRIVER);
5681 		break;
5682 	default:
5683 		error = ENOTTY;
5684 		break;
5685 	}
5686 	if (error) {
5687 		mtx_unlock(&Giant);
5688 		return (error);
5689 	}
5690 
5691 	/* Perform the requested operation. */
5692 	switch (cmd) {
5693 	case DEV_ATTACH:
5694 		if (device_is_attached(dev) && (dev->flags & DF_REBID) == 0)
5695 			error = EBUSY;
5696 		else if (!device_is_enabled(dev))
5697 			error = ENXIO;
5698 		else
5699 			error = device_probe_and_attach(dev);
5700 		break;
5701 	case DEV_DETACH:
5702 		if (!device_is_attached(dev)) {
5703 			error = ENXIO;
5704 			break;
5705 		}
5706 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5707 			error = device_quiesce(dev);
5708 			if (error)
5709 				break;
5710 		}
5711 		error = device_detach(dev);
5712 		break;
5713 	case DEV_ENABLE:
5714 		if (device_is_enabled(dev)) {
5715 			error = EBUSY;
5716 			break;
5717 		}
5718 
5719 		/*
5720 		 * If the device has been probed but not attached (e.g.
5721 		 * when it has been disabled by a loader hint), just
5722 		 * attach the device rather than doing a full probe.
5723 		 */
5724 		device_enable(dev);
5725 		if (device_is_alive(dev)) {
5726 			/*
5727 			 * If the device was disabled via a hint, clear
5728 			 * the hint.
5729 			 */
5730 			if (resource_disabled(dev->driver->name, dev->unit))
5731 				resource_unset_value(dev->driver->name,
5732 				    dev->unit, "disabled");
5733 			error = device_attach(dev);
5734 		} else
5735 			error = device_probe_and_attach(dev);
5736 		break;
5737 	case DEV_DISABLE:
5738 		if (!device_is_enabled(dev)) {
5739 			error = ENXIO;
5740 			break;
5741 		}
5742 
5743 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5744 			error = device_quiesce(dev);
5745 			if (error)
5746 				break;
5747 		}
5748 
5749 		/*
5750 		 * Force DF_FIXEDCLASS on around detach to preserve
5751 		 * the existing name.
5752 		 */
5753 		old = dev->flags;
5754 		dev->flags |= DF_FIXEDCLASS;
5755 		error = device_detach(dev);
5756 		if (!(old & DF_FIXEDCLASS))
5757 			dev->flags &= ~DF_FIXEDCLASS;
5758 		if (error == 0)
5759 			device_disable(dev);
5760 		break;
5761 	case DEV_SUSPEND:
5762 		if (device_is_suspended(dev)) {
5763 			error = EBUSY;
5764 			break;
5765 		}
5766 		if (device_get_parent(dev) == NULL) {
5767 			error = EINVAL;
5768 			break;
5769 		}
5770 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5771 		break;
5772 	case DEV_RESUME:
5773 		if (!device_is_suspended(dev)) {
5774 			error = EINVAL;
5775 			break;
5776 		}
5777 		if (device_get_parent(dev) == NULL) {
5778 			error = EINVAL;
5779 			break;
5780 		}
5781 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5782 		break;
5783 	case DEV_SET_DRIVER: {
5784 		devclass_t dc;
5785 		char driver[128];
5786 
5787 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5788 		if (error)
5789 			break;
5790 		if (driver[0] == '\0') {
5791 			error = EINVAL;
5792 			break;
5793 		}
5794 		if (dev->devclass != NULL &&
5795 		    strcmp(driver, dev->devclass->name) == 0)
5796 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5797 			break;
5798 
5799 		/*
5800 		 * Scan drivers for this device's bus looking for at
5801 		 * least one matching driver.
5802 		 */
5803 		if (dev->parent == NULL) {
5804 			error = EINVAL;
5805 			break;
5806 		}
5807 		if (!driver_exists(dev->parent, driver)) {
5808 			error = ENOENT;
5809 			break;
5810 		}
5811 		dc = devclass_create(driver);
5812 		if (dc == NULL) {
5813 			error = ENOMEM;
5814 			break;
5815 		}
5816 
5817 		/* Detach device if necessary. */
5818 		if (device_is_attached(dev)) {
5819 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5820 				error = device_detach(dev);
5821 			else
5822 				error = EBUSY;
5823 			if (error)
5824 				break;
5825 		}
5826 
5827 		/* Clear any previously-fixed device class and unit. */
5828 		if (dev->flags & DF_FIXEDCLASS)
5829 			devclass_delete_device(dev->devclass, dev);
5830 		dev->flags |= DF_WILDCARD;
5831 		dev->unit = -1;
5832 
5833 		/* Force the new device class. */
5834 		error = devclass_add_device(dc, dev);
5835 		if (error)
5836 			break;
5837 		dev->flags |= DF_FIXEDCLASS;
5838 		error = device_probe_and_attach(dev);
5839 		break;
5840 	}
5841 	case DEV_CLEAR_DRIVER:
5842 		if (!(dev->flags & DF_FIXEDCLASS)) {
5843 			error = 0;
5844 			break;
5845 		}
5846 		if (device_is_attached(dev)) {
5847 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5848 				error = device_detach(dev);
5849 			else
5850 				error = EBUSY;
5851 			if (error)
5852 				break;
5853 		}
5854 
5855 		dev->flags &= ~DF_FIXEDCLASS;
5856 		dev->flags |= DF_WILDCARD;
5857 		devclass_delete_device(dev->devclass, dev);
5858 		error = device_probe_and_attach(dev);
5859 		break;
5860 	case DEV_RESCAN:
5861 		if (!device_is_attached(dev)) {
5862 			error = ENXIO;
5863 			break;
5864 		}
5865 		error = BUS_RESCAN(dev);
5866 		break;
5867 	case DEV_DELETE: {
5868 		device_t parent;
5869 
5870 		parent = device_get_parent(dev);
5871 		if (parent == NULL) {
5872 			error = EINVAL;
5873 			break;
5874 		}
5875 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5876 			if (bus_child_present(dev) != 0) {
5877 				error = EBUSY;
5878 				break;
5879 			}
5880 		}
5881 
5882 		error = device_delete_child(parent, dev);
5883 		break;
5884 	}
5885 	case DEV_FREEZE:
5886 		if (device_frozen)
5887 			error = EBUSY;
5888 		else
5889 			device_frozen = true;
5890 		break;
5891 	case DEV_THAW:
5892 		if (!device_frozen)
5893 			error = EBUSY;
5894 		else {
5895 			device_do_deferred_actions();
5896 			device_frozen = false;
5897 		}
5898 		break;
5899 	case DEV_RESET:
5900 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5901 			error = EINVAL;
5902 			break;
5903 		}
5904 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5905 		    req->dr_flags);
5906 		break;
5907 	}
5908 	mtx_unlock(&Giant);
5909 	return (error);
5910 }
5911 
5912 static struct cdevsw devctl2_cdevsw = {
5913 	.d_version =	D_VERSION,
5914 	.d_ioctl =	devctl2_ioctl,
5915 	.d_name =	"devctl2",
5916 };
5917 
5918 static void
5919 devctl2_init(void)
5920 {
5921 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5922 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5923 }
5924 
5925 /*
5926  * APIs to manage deprecation and obsolescence.
5927  */
5928 static int obsolete_panic = 0;
5929 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
5930     "Panic when obsolete features are used (0 = never, 1 = if osbolete, "
5931     "2 = if deprecated)");
5932 
5933 static void
5934 gone_panic(int major, int running, const char *msg)
5935 {
5936 	switch (obsolete_panic)
5937 	{
5938 	case 0:
5939 		return;
5940 	case 1:
5941 		if (running < major)
5942 			return;
5943 		/* FALLTHROUGH */
5944 	default:
5945 		panic("%s", msg);
5946 	}
5947 }
5948 
5949 void
5950 _gone_in(int major, const char *msg)
5951 {
5952 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5953 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5954 		printf("Obsolete code will be removed soon: %s\n", msg);
5955 	else
5956 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
5957 		    major, msg);
5958 }
5959 
5960 void
5961 _gone_in_dev(device_t dev, int major, const char *msg)
5962 {
5963 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5964 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5965 		device_printf(dev,
5966 		    "Obsolete code will be removed soon: %s\n", msg);
5967 	else
5968 		device_printf(dev,
5969 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
5970 		    major, msg);
5971 }
5972 
5973 #ifdef DDB
5974 DB_SHOW_COMMAND(device, db_show_device)
5975 {
5976 	device_t dev;
5977 
5978 	if (!have_addr)
5979 		return;
5980 
5981 	dev = (device_t)addr;
5982 
5983 	db_printf("name:    %s\n", device_get_nameunit(dev));
5984 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
5985 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
5986 	db_printf("  addr:    %p\n", dev);
5987 	db_printf("  parent:  %p\n", dev->parent);
5988 	db_printf("  softc:   %p\n", dev->softc);
5989 	db_printf("  ivars:   %p\n", dev->ivars);
5990 }
5991 
5992 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
5993 {
5994 	device_t dev;
5995 
5996 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5997 		db_show_device((db_expr_t)dev, true, count, modif);
5998 	}
5999 }
6000 #endif
6001