xref: /freebsd/sys/kern/subr_bus.c (revision d5e3895ea4fe4ef9db8823774e07b4368180a23e)
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  *
864  * @param sb	sbuf to place the characters into
865  * @param src	Original buffer.
866  */
867 void
868 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
869 {
870 	while (*src != '\0') {
871 		if (*src == '"' || *src == '\\')
872 			sbuf_putc(sb, '\\');
873 		sbuf_putc(sb, *src++);
874 	}
875 }
876 
877 /* End of /dev/devctl code */
878 
879 static TAILQ_HEAD(,device)	bus_data_devices;
880 static int bus_data_generation = 1;
881 
882 static kobj_method_t null_methods[] = {
883 	KOBJMETHOD_END
884 };
885 
886 DEFINE_CLASS(null, null_methods, 0);
887 
888 /*
889  * Bus pass implementation
890  */
891 
892 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
893 int bus_current_pass = BUS_PASS_ROOT;
894 
895 /**
896  * @internal
897  * @brief Register the pass level of a new driver attachment
898  *
899  * Register a new driver attachment's pass level.  If no driver
900  * attachment with the same pass level has been added, then @p new
901  * will be added to the global passes list.
902  *
903  * @param new		the new driver attachment
904  */
905 static void
906 driver_register_pass(struct driverlink *new)
907 {
908 	struct driverlink *dl;
909 
910 	/* We only consider pass numbers during boot. */
911 	if (bus_current_pass == BUS_PASS_DEFAULT)
912 		return;
913 
914 	/*
915 	 * Walk the passes list.  If we already know about this pass
916 	 * then there is nothing to do.  If we don't, then insert this
917 	 * driver link into the list.
918 	 */
919 	TAILQ_FOREACH(dl, &passes, passlink) {
920 		if (dl->pass < new->pass)
921 			continue;
922 		if (dl->pass == new->pass)
923 			return;
924 		TAILQ_INSERT_BEFORE(dl, new, passlink);
925 		return;
926 	}
927 	TAILQ_INSERT_TAIL(&passes, new, passlink);
928 }
929 
930 /**
931  * @brief Raise the current bus pass
932  *
933  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
934  * method on the root bus to kick off a new device tree scan for each
935  * new pass level that has at least one driver.
936  */
937 void
938 bus_set_pass(int pass)
939 {
940 	struct driverlink *dl;
941 
942 	if (bus_current_pass > pass)
943 		panic("Attempt to lower bus pass level");
944 
945 	TAILQ_FOREACH(dl, &passes, passlink) {
946 		/* Skip pass values below the current pass level. */
947 		if (dl->pass <= bus_current_pass)
948 			continue;
949 
950 		/*
951 		 * Bail once we hit a driver with a pass level that is
952 		 * too high.
953 		 */
954 		if (dl->pass > pass)
955 			break;
956 
957 		/*
958 		 * Raise the pass level to the next level and rescan
959 		 * the tree.
960 		 */
961 		bus_current_pass = dl->pass;
962 		BUS_NEW_PASS(root_bus);
963 	}
964 
965 	/*
966 	 * If there isn't a driver registered for the requested pass,
967 	 * then bus_current_pass might still be less than 'pass'.  Set
968 	 * it to 'pass' in that case.
969 	 */
970 	if (bus_current_pass < pass)
971 		bus_current_pass = pass;
972 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
973 }
974 
975 /*
976  * Devclass implementation
977  */
978 
979 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
980 
981 /**
982  * @internal
983  * @brief Find or create a device class
984  *
985  * If a device class with the name @p classname exists, return it,
986  * otherwise if @p create is non-zero create and return a new device
987  * class.
988  *
989  * If @p parentname is non-NULL, the parent of the devclass is set to
990  * the devclass of that name.
991  *
992  * @param classname	the devclass name to find or create
993  * @param parentname	the parent devclass name or @c NULL
994  * @param create	non-zero to create a devclass
995  */
996 static devclass_t
997 devclass_find_internal(const char *classname, const char *parentname,
998 		       int create)
999 {
1000 	devclass_t dc;
1001 
1002 	PDEBUG(("looking for %s", classname));
1003 	if (!classname)
1004 		return (NULL);
1005 
1006 	TAILQ_FOREACH(dc, &devclasses, link) {
1007 		if (!strcmp(dc->name, classname))
1008 			break;
1009 	}
1010 
1011 	if (create && !dc) {
1012 		PDEBUG(("creating %s", classname));
1013 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1014 		    M_BUS, M_NOWAIT | M_ZERO);
1015 		if (!dc)
1016 			return (NULL);
1017 		dc->parent = NULL;
1018 		dc->name = (char*) (dc + 1);
1019 		strcpy(dc->name, classname);
1020 		TAILQ_INIT(&dc->drivers);
1021 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1022 
1023 		bus_data_generation_update();
1024 	}
1025 
1026 	/*
1027 	 * If a parent class is specified, then set that as our parent so
1028 	 * that this devclass will support drivers for the parent class as
1029 	 * well.  If the parent class has the same name don't do this though
1030 	 * as it creates a cycle that can trigger an infinite loop in
1031 	 * device_probe_child() if a device exists for which there is no
1032 	 * suitable driver.
1033 	 */
1034 	if (parentname && dc && !dc->parent &&
1035 	    strcmp(classname, parentname) != 0) {
1036 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1037 		dc->parent->flags |= DC_HAS_CHILDREN;
1038 	}
1039 
1040 	return (dc);
1041 }
1042 
1043 /**
1044  * @brief Create a device class
1045  *
1046  * If a device class with the name @p classname exists, return it,
1047  * otherwise create and return a new device class.
1048  *
1049  * @param classname	the devclass name to find or create
1050  */
1051 devclass_t
1052 devclass_create(const char *classname)
1053 {
1054 	return (devclass_find_internal(classname, NULL, TRUE));
1055 }
1056 
1057 /**
1058  * @brief Find a device class
1059  *
1060  * If a device class with the name @p classname exists, return it,
1061  * otherwise return @c NULL.
1062  *
1063  * @param classname	the devclass name to find
1064  */
1065 devclass_t
1066 devclass_find(const char *classname)
1067 {
1068 	return (devclass_find_internal(classname, NULL, FALSE));
1069 }
1070 
1071 /**
1072  * @brief Register that a device driver has been added to a devclass
1073  *
1074  * Register that a device driver has been added to a devclass.  This
1075  * is called by devclass_add_driver to accomplish the recursive
1076  * notification of all the children classes of dc, as well as dc.
1077  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1078  * the devclass.
1079  *
1080  * We do a full search here of the devclass list at each iteration
1081  * level to save storing children-lists in the devclass structure.  If
1082  * we ever move beyond a few dozen devices doing this, we may need to
1083  * reevaluate...
1084  *
1085  * @param dc		the devclass to edit
1086  * @param driver	the driver that was just added
1087  */
1088 static void
1089 devclass_driver_added(devclass_t dc, driver_t *driver)
1090 {
1091 	devclass_t parent;
1092 	int i;
1093 
1094 	/*
1095 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1096 	 */
1097 	for (i = 0; i < dc->maxunit; i++)
1098 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1099 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1100 
1101 	/*
1102 	 * Walk through the children classes.  Since we only keep a
1103 	 * single parent pointer around, we walk the entire list of
1104 	 * devclasses looking for children.  We set the
1105 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1106 	 * the parent, so we only walk the list for those devclasses
1107 	 * that have children.
1108 	 */
1109 	if (!(dc->flags & DC_HAS_CHILDREN))
1110 		return;
1111 	parent = dc;
1112 	TAILQ_FOREACH(dc, &devclasses, link) {
1113 		if (dc->parent == parent)
1114 			devclass_driver_added(dc, driver);
1115 	}
1116 }
1117 
1118 /**
1119  * @brief Add a device driver to a device class
1120  *
1121  * Add a device driver to a devclass. This is normally called
1122  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1123  * all devices in the devclass will be called to allow them to attempt
1124  * to re-probe any unmatched children.
1125  *
1126  * @param dc		the devclass to edit
1127  * @param driver	the driver to register
1128  */
1129 int
1130 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1131 {
1132 	driverlink_t dl;
1133 	const char *parentname;
1134 
1135 	PDEBUG(("%s", DRIVERNAME(driver)));
1136 
1137 	/* Don't allow invalid pass values. */
1138 	if (pass <= BUS_PASS_ROOT)
1139 		return (EINVAL);
1140 
1141 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1142 	if (!dl)
1143 		return (ENOMEM);
1144 
1145 	/*
1146 	 * Compile the driver's methods. Also increase the reference count
1147 	 * so that the class doesn't get freed when the last instance
1148 	 * goes. This means we can safely use static methods and avoids a
1149 	 * double-free in devclass_delete_driver.
1150 	 */
1151 	kobj_class_compile((kobj_class_t) driver);
1152 
1153 	/*
1154 	 * If the driver has any base classes, make the
1155 	 * devclass inherit from the devclass of the driver's
1156 	 * first base class. This will allow the system to
1157 	 * search for drivers in both devclasses for children
1158 	 * of a device using this driver.
1159 	 */
1160 	if (driver->baseclasses)
1161 		parentname = driver->baseclasses[0]->name;
1162 	else
1163 		parentname = NULL;
1164 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1165 
1166 	dl->driver = driver;
1167 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1168 	driver->refs++;		/* XXX: kobj_mtx */
1169 	dl->pass = pass;
1170 	driver_register_pass(dl);
1171 
1172 	if (device_frozen) {
1173 		dl->flags |= DL_DEFERRED_PROBE;
1174 	} else {
1175 		devclass_driver_added(dc, driver);
1176 	}
1177 	bus_data_generation_update();
1178 	return (0);
1179 }
1180 
1181 /**
1182  * @brief Register that a device driver has been deleted from a devclass
1183  *
1184  * Register that a device driver has been removed from a devclass.
1185  * This is called by devclass_delete_driver to accomplish the
1186  * recursive notification of all the children classes of busclass, as
1187  * well as busclass.  Each layer will attempt to detach the driver
1188  * from any devices that are children of the bus's devclass.  The function
1189  * will return an error if a device fails to detach.
1190  *
1191  * We do a full search here of the devclass list at each iteration
1192  * level to save storing children-lists in the devclass structure.  If
1193  * we ever move beyond a few dozen devices doing this, we may need to
1194  * reevaluate...
1195  *
1196  * @param busclass	the devclass of the parent bus
1197  * @param dc		the devclass of the driver being deleted
1198  * @param driver	the driver being deleted
1199  */
1200 static int
1201 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1202 {
1203 	devclass_t parent;
1204 	device_t dev;
1205 	int error, i;
1206 
1207 	/*
1208 	 * Disassociate from any devices.  We iterate through all the
1209 	 * devices in the devclass of the driver and detach any which are
1210 	 * using the driver and which have a parent in the devclass which
1211 	 * we are deleting from.
1212 	 *
1213 	 * Note that since a driver can be in multiple devclasses, we
1214 	 * should not detach devices which are not children of devices in
1215 	 * the affected devclass.
1216 	 *
1217 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1218 	 * generate later.
1219 	 */
1220 	for (i = 0; i < dc->maxunit; i++) {
1221 		if (dc->devices[i]) {
1222 			dev = dc->devices[i];
1223 			if (dev->driver == driver && dev->parent &&
1224 			    dev->parent->devclass == busclass) {
1225 				if ((error = device_detach(dev)) != 0)
1226 					return (error);
1227 				if (device_frozen) {
1228 					dev->flags &= ~DF_DONENOMATCH;
1229 					dev->flags |= DF_NEEDNOMATCH;
1230 				} else {
1231 					BUS_PROBE_NOMATCH(dev->parent, dev);
1232 					devnomatch(dev);
1233 					dev->flags |= DF_DONENOMATCH;
1234 				}
1235 			}
1236 		}
1237 	}
1238 
1239 	/*
1240 	 * Walk through the children classes.  Since we only keep a
1241 	 * single parent pointer around, we walk the entire list of
1242 	 * devclasses looking for children.  We set the
1243 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1244 	 * the parent, so we only walk the list for those devclasses
1245 	 * that have children.
1246 	 */
1247 	if (!(busclass->flags & DC_HAS_CHILDREN))
1248 		return (0);
1249 	parent = busclass;
1250 	TAILQ_FOREACH(busclass, &devclasses, link) {
1251 		if (busclass->parent == parent) {
1252 			error = devclass_driver_deleted(busclass, dc, driver);
1253 			if (error)
1254 				return (error);
1255 		}
1256 	}
1257 	return (0);
1258 }
1259 
1260 /**
1261  * @brief Delete a device driver from a device class
1262  *
1263  * Delete a device driver from a devclass. This is normally called
1264  * automatically by DRIVER_MODULE().
1265  *
1266  * If the driver is currently attached to any devices,
1267  * devclass_delete_driver() will first attempt to detach from each
1268  * device. If one of the detach calls fails, the driver will not be
1269  * deleted.
1270  *
1271  * @param dc		the devclass to edit
1272  * @param driver	the driver to unregister
1273  */
1274 int
1275 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1276 {
1277 	devclass_t dc = devclass_find(driver->name);
1278 	driverlink_t dl;
1279 	int error;
1280 
1281 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1282 
1283 	if (!dc)
1284 		return (0);
1285 
1286 	/*
1287 	 * Find the link structure in the bus' list of drivers.
1288 	 */
1289 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1290 		if (dl->driver == driver)
1291 			break;
1292 	}
1293 
1294 	if (!dl) {
1295 		PDEBUG(("%s not found in %s list", driver->name,
1296 		    busclass->name));
1297 		return (ENOENT);
1298 	}
1299 
1300 	error = devclass_driver_deleted(busclass, dc, driver);
1301 	if (error != 0)
1302 		return (error);
1303 
1304 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1305 	free(dl, M_BUS);
1306 
1307 	/* XXX: kobj_mtx */
1308 	driver->refs--;
1309 	if (driver->refs == 0)
1310 		kobj_class_free((kobj_class_t) driver);
1311 
1312 	bus_data_generation_update();
1313 	return (0);
1314 }
1315 
1316 /**
1317  * @brief Quiesces a set of device drivers from a device class
1318  *
1319  * Quiesce a device driver from a devclass. This is normally called
1320  * automatically by DRIVER_MODULE().
1321  *
1322  * If the driver is currently attached to any devices,
1323  * devclass_quiesece_driver() will first attempt to quiesce each
1324  * device.
1325  *
1326  * @param dc		the devclass to edit
1327  * @param driver	the driver to unregister
1328  */
1329 static int
1330 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1331 {
1332 	devclass_t dc = devclass_find(driver->name);
1333 	driverlink_t dl;
1334 	device_t dev;
1335 	int i;
1336 	int error;
1337 
1338 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1339 
1340 	if (!dc)
1341 		return (0);
1342 
1343 	/*
1344 	 * Find the link structure in the bus' list of drivers.
1345 	 */
1346 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1347 		if (dl->driver == driver)
1348 			break;
1349 	}
1350 
1351 	if (!dl) {
1352 		PDEBUG(("%s not found in %s list", driver->name,
1353 		    busclass->name));
1354 		return (ENOENT);
1355 	}
1356 
1357 	/*
1358 	 * Quiesce all devices.  We iterate through all the devices in
1359 	 * the devclass of the driver and quiesce any which are using
1360 	 * the driver and which have a parent in the devclass which we
1361 	 * are quiescing.
1362 	 *
1363 	 * Note that since a driver can be in multiple devclasses, we
1364 	 * should not quiesce devices which are not children of
1365 	 * devices in the affected devclass.
1366 	 */
1367 	for (i = 0; i < dc->maxunit; i++) {
1368 		if (dc->devices[i]) {
1369 			dev = dc->devices[i];
1370 			if (dev->driver == driver && dev->parent &&
1371 			    dev->parent->devclass == busclass) {
1372 				if ((error = device_quiesce(dev)) != 0)
1373 					return (error);
1374 			}
1375 		}
1376 	}
1377 
1378 	return (0);
1379 }
1380 
1381 /**
1382  * @internal
1383  */
1384 static driverlink_t
1385 devclass_find_driver_internal(devclass_t dc, const char *classname)
1386 {
1387 	driverlink_t dl;
1388 
1389 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1390 
1391 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1392 		if (!strcmp(dl->driver->name, classname))
1393 			return (dl);
1394 	}
1395 
1396 	PDEBUG(("not found"));
1397 	return (NULL);
1398 }
1399 
1400 /**
1401  * @brief Return the name of the devclass
1402  */
1403 const char *
1404 devclass_get_name(devclass_t dc)
1405 {
1406 	return (dc->name);
1407 }
1408 
1409 /**
1410  * @brief Find a device given a unit number
1411  *
1412  * @param dc		the devclass to search
1413  * @param unit		the unit number to search for
1414  *
1415  * @returns		the device with the given unit number or @c
1416  *			NULL if there is no such device
1417  */
1418 device_t
1419 devclass_get_device(devclass_t dc, int unit)
1420 {
1421 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1422 		return (NULL);
1423 	return (dc->devices[unit]);
1424 }
1425 
1426 /**
1427  * @brief Find the softc field of a device given a unit number
1428  *
1429  * @param dc		the devclass to search
1430  * @param unit		the unit number to search for
1431  *
1432  * @returns		the softc field of the device with the given
1433  *			unit number or @c NULL if there is no such
1434  *			device
1435  */
1436 void *
1437 devclass_get_softc(devclass_t dc, int unit)
1438 {
1439 	device_t dev;
1440 
1441 	dev = devclass_get_device(dc, unit);
1442 	if (!dev)
1443 		return (NULL);
1444 
1445 	return (device_get_softc(dev));
1446 }
1447 
1448 /**
1449  * @brief Get a list of devices in the devclass
1450  *
1451  * An array containing a list of all the devices in the given devclass
1452  * is allocated and returned in @p *devlistp. The number of devices
1453  * in the array is returned in @p *devcountp. The caller should free
1454  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1455  *
1456  * @param dc		the devclass to examine
1457  * @param devlistp	points at location for array pointer return
1458  *			value
1459  * @param devcountp	points at location for array size return value
1460  *
1461  * @retval 0		success
1462  * @retval ENOMEM	the array allocation failed
1463  */
1464 int
1465 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1466 {
1467 	int count, i;
1468 	device_t *list;
1469 
1470 	count = devclass_get_count(dc);
1471 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1472 	if (!list)
1473 		return (ENOMEM);
1474 
1475 	count = 0;
1476 	for (i = 0; i < dc->maxunit; i++) {
1477 		if (dc->devices[i]) {
1478 			list[count] = dc->devices[i];
1479 			count++;
1480 		}
1481 	}
1482 
1483 	*devlistp = list;
1484 	*devcountp = count;
1485 
1486 	return (0);
1487 }
1488 
1489 /**
1490  * @brief Get a list of drivers in the devclass
1491  *
1492  * An array containing a list of pointers to all the drivers in the
1493  * given devclass is allocated and returned in @p *listp.  The number
1494  * of drivers in the array is returned in @p *countp. The caller should
1495  * free the array using @c free(p, M_TEMP).
1496  *
1497  * @param dc		the devclass to examine
1498  * @param listp		gives location for array pointer return value
1499  * @param countp	gives location for number of array elements
1500  *			return value
1501  *
1502  * @retval 0		success
1503  * @retval ENOMEM	the array allocation failed
1504  */
1505 int
1506 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1507 {
1508 	driverlink_t dl;
1509 	driver_t **list;
1510 	int count;
1511 
1512 	count = 0;
1513 	TAILQ_FOREACH(dl, &dc->drivers, link)
1514 		count++;
1515 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1516 	if (list == NULL)
1517 		return (ENOMEM);
1518 
1519 	count = 0;
1520 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1521 		list[count] = dl->driver;
1522 		count++;
1523 	}
1524 	*listp = list;
1525 	*countp = count;
1526 
1527 	return (0);
1528 }
1529 
1530 /**
1531  * @brief Get the number of devices in a devclass
1532  *
1533  * @param dc		the devclass to examine
1534  */
1535 int
1536 devclass_get_count(devclass_t dc)
1537 {
1538 	int count, i;
1539 
1540 	count = 0;
1541 	for (i = 0; i < dc->maxunit; i++)
1542 		if (dc->devices[i])
1543 			count++;
1544 	return (count);
1545 }
1546 
1547 /**
1548  * @brief Get the maximum unit number used in a devclass
1549  *
1550  * Note that this is one greater than the highest currently-allocated
1551  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1552  * that not even the devclass has been allocated yet.
1553  *
1554  * @param dc		the devclass to examine
1555  */
1556 int
1557 devclass_get_maxunit(devclass_t dc)
1558 {
1559 	if (dc == NULL)
1560 		return (-1);
1561 	return (dc->maxunit);
1562 }
1563 
1564 /**
1565  * @brief Find a free unit number in a devclass
1566  *
1567  * This function searches for the first unused unit number greater
1568  * that or equal to @p unit.
1569  *
1570  * @param dc		the devclass to examine
1571  * @param unit		the first unit number to check
1572  */
1573 int
1574 devclass_find_free_unit(devclass_t dc, int unit)
1575 {
1576 	if (dc == NULL)
1577 		return (unit);
1578 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1579 		unit++;
1580 	return (unit);
1581 }
1582 
1583 /**
1584  * @brief Set the parent of a devclass
1585  *
1586  * The parent class is normally initialised automatically by
1587  * DRIVER_MODULE().
1588  *
1589  * @param dc		the devclass to edit
1590  * @param pdc		the new parent devclass
1591  */
1592 void
1593 devclass_set_parent(devclass_t dc, devclass_t pdc)
1594 {
1595 	dc->parent = pdc;
1596 }
1597 
1598 /**
1599  * @brief Get the parent of a devclass
1600  *
1601  * @param dc		the devclass to examine
1602  */
1603 devclass_t
1604 devclass_get_parent(devclass_t dc)
1605 {
1606 	return (dc->parent);
1607 }
1608 
1609 struct sysctl_ctx_list *
1610 devclass_get_sysctl_ctx(devclass_t dc)
1611 {
1612 	return (&dc->sysctl_ctx);
1613 }
1614 
1615 struct sysctl_oid *
1616 devclass_get_sysctl_tree(devclass_t dc)
1617 {
1618 	return (dc->sysctl_tree);
1619 }
1620 
1621 /**
1622  * @internal
1623  * @brief Allocate a unit number
1624  *
1625  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1626  * will do). The allocated unit number is returned in @p *unitp.
1627 
1628  * @param dc		the devclass to allocate from
1629  * @param unitp		points at the location for the allocated unit
1630  *			number
1631  *
1632  * @retval 0		success
1633  * @retval EEXIST	the requested unit number is already allocated
1634  * @retval ENOMEM	memory allocation failure
1635  */
1636 static int
1637 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1638 {
1639 	const char *s;
1640 	int unit = *unitp;
1641 
1642 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1643 
1644 	/* Ask the parent bus if it wants to wire this device. */
1645 	if (unit == -1)
1646 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1647 		    &unit);
1648 
1649 	/* If we were given a wired unit number, check for existing device */
1650 	/* XXX imp XXX */
1651 	if (unit != -1) {
1652 		if (unit >= 0 && unit < dc->maxunit &&
1653 		    dc->devices[unit] != NULL) {
1654 			if (bootverbose)
1655 				printf("%s: %s%d already exists; skipping it\n",
1656 				    dc->name, dc->name, *unitp);
1657 			return (EEXIST);
1658 		}
1659 	} else {
1660 		/* Unwired device, find the next available slot for it */
1661 		unit = 0;
1662 		for (unit = 0;; unit++) {
1663 			/* If there is an "at" hint for a unit then skip it. */
1664 			if (resource_string_value(dc->name, unit, "at", &s) ==
1665 			    0)
1666 				continue;
1667 
1668 			/* If this device slot is already in use, skip it. */
1669 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1670 				continue;
1671 
1672 			break;
1673 		}
1674 	}
1675 
1676 	/*
1677 	 * We've selected a unit beyond the length of the table, so let's
1678 	 * extend the table to make room for all units up to and including
1679 	 * this one.
1680 	 */
1681 	if (unit >= dc->maxunit) {
1682 		device_t *newlist, *oldlist;
1683 		int newsize;
1684 
1685 		oldlist = dc->devices;
1686 		newsize = roundup((unit + 1),
1687 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1688 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1689 		if (!newlist)
1690 			return (ENOMEM);
1691 		if (oldlist != NULL)
1692 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1693 		bzero(newlist + dc->maxunit,
1694 		    sizeof(device_t) * (newsize - dc->maxunit));
1695 		dc->devices = newlist;
1696 		dc->maxunit = newsize;
1697 		if (oldlist != NULL)
1698 			free(oldlist, M_BUS);
1699 	}
1700 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1701 
1702 	*unitp = unit;
1703 	return (0);
1704 }
1705 
1706 /**
1707  * @internal
1708  * @brief Add a device to a devclass
1709  *
1710  * A unit number is allocated for the device (using the device's
1711  * preferred unit number if any) and the device is registered in the
1712  * devclass. This allows the device to be looked up by its unit
1713  * number, e.g. by decoding a dev_t minor number.
1714  *
1715  * @param dc		the devclass to add to
1716  * @param dev		the device to add
1717  *
1718  * @retval 0		success
1719  * @retval EEXIST	the requested unit number is already allocated
1720  * @retval ENOMEM	memory allocation failure
1721  */
1722 static int
1723 devclass_add_device(devclass_t dc, device_t dev)
1724 {
1725 	int buflen, error;
1726 
1727 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1728 
1729 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1730 	if (buflen < 0)
1731 		return (ENOMEM);
1732 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1733 	if (!dev->nameunit)
1734 		return (ENOMEM);
1735 
1736 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1737 		free(dev->nameunit, M_BUS);
1738 		dev->nameunit = NULL;
1739 		return (error);
1740 	}
1741 	dc->devices[dev->unit] = dev;
1742 	dev->devclass = dc;
1743 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1744 
1745 	return (0);
1746 }
1747 
1748 /**
1749  * @internal
1750  * @brief Delete a device from a devclass
1751  *
1752  * The device is removed from the devclass's device list and its unit
1753  * number is freed.
1754 
1755  * @param dc		the devclass to delete from
1756  * @param dev		the device to delete
1757  *
1758  * @retval 0		success
1759  */
1760 static int
1761 devclass_delete_device(devclass_t dc, device_t dev)
1762 {
1763 	if (!dc || !dev)
1764 		return (0);
1765 
1766 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1767 
1768 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1769 		panic("devclass_delete_device: inconsistent device class");
1770 	dc->devices[dev->unit] = NULL;
1771 	if (dev->flags & DF_WILDCARD)
1772 		dev->unit = -1;
1773 	dev->devclass = NULL;
1774 	free(dev->nameunit, M_BUS);
1775 	dev->nameunit = NULL;
1776 
1777 	return (0);
1778 }
1779 
1780 /**
1781  * @internal
1782  * @brief Make a new device and add it as a child of @p parent
1783  *
1784  * @param parent	the parent of the new device
1785  * @param name		the devclass name of the new device or @c NULL
1786  *			to leave the devclass unspecified
1787  * @parem unit		the unit number of the new device of @c -1 to
1788  *			leave the unit number unspecified
1789  *
1790  * @returns the new device
1791  */
1792 static device_t
1793 make_device(device_t parent, const char *name, int unit)
1794 {
1795 	device_t dev;
1796 	devclass_t dc;
1797 
1798 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1799 
1800 	if (name) {
1801 		dc = devclass_find_internal(name, NULL, TRUE);
1802 		if (!dc) {
1803 			printf("make_device: can't find device class %s\n",
1804 			    name);
1805 			return (NULL);
1806 		}
1807 	} else {
1808 		dc = NULL;
1809 	}
1810 
1811 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1812 	if (!dev)
1813 		return (NULL);
1814 
1815 	dev->parent = parent;
1816 	TAILQ_INIT(&dev->children);
1817 	kobj_init((kobj_t) dev, &null_class);
1818 	dev->driver = NULL;
1819 	dev->devclass = NULL;
1820 	dev->unit = unit;
1821 	dev->nameunit = NULL;
1822 	dev->desc = NULL;
1823 	dev->busy = 0;
1824 	dev->devflags = 0;
1825 	dev->flags = DF_ENABLED;
1826 	dev->order = 0;
1827 	if (unit == -1)
1828 		dev->flags |= DF_WILDCARD;
1829 	if (name) {
1830 		dev->flags |= DF_FIXEDCLASS;
1831 		if (devclass_add_device(dc, dev)) {
1832 			kobj_delete((kobj_t) dev, M_BUS);
1833 			return (NULL);
1834 		}
1835 	}
1836 	if (parent != NULL && device_has_quiet_children(parent))
1837 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1838 	dev->ivars = NULL;
1839 	dev->softc = NULL;
1840 
1841 	dev->state = DS_NOTPRESENT;
1842 
1843 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1844 	bus_data_generation_update();
1845 
1846 	return (dev);
1847 }
1848 
1849 /**
1850  * @internal
1851  * @brief Print a description of a device.
1852  */
1853 static int
1854 device_print_child(device_t dev, device_t child)
1855 {
1856 	int retval = 0;
1857 
1858 	if (device_is_alive(child))
1859 		retval += BUS_PRINT_CHILD(dev, child);
1860 	else
1861 		retval += device_printf(child, " not found\n");
1862 
1863 	return (retval);
1864 }
1865 
1866 /**
1867  * @brief Create a new device
1868  *
1869  * This creates a new device and adds it as a child of an existing
1870  * parent device. The new device will be added after the last existing
1871  * child with order zero.
1872  *
1873  * @param dev		the device which will be the parent of the
1874  *			new child device
1875  * @param name		devclass name for new device or @c NULL if not
1876  *			specified
1877  * @param unit		unit number for new device or @c -1 if not
1878  *			specified
1879  *
1880  * @returns		the new device
1881  */
1882 device_t
1883 device_add_child(device_t dev, const char *name, int unit)
1884 {
1885 	return (device_add_child_ordered(dev, 0, name, unit));
1886 }
1887 
1888 /**
1889  * @brief Create a new device
1890  *
1891  * This creates a new device and adds it as a child of an existing
1892  * parent device. The new device will be added after the last existing
1893  * child with the same order.
1894  *
1895  * @param dev		the device which will be the parent of the
1896  *			new child device
1897  * @param order		a value which is used to partially sort the
1898  *			children of @p dev - devices created using
1899  *			lower values of @p order appear first in @p
1900  *			dev's list of children
1901  * @param name		devclass name for new device or @c NULL if not
1902  *			specified
1903  * @param unit		unit number for new device or @c -1 if not
1904  *			specified
1905  *
1906  * @returns		the new device
1907  */
1908 device_t
1909 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1910 {
1911 	device_t child;
1912 	device_t place;
1913 
1914 	PDEBUG(("%s at %s with order %u as unit %d",
1915 	    name, DEVICENAME(dev), order, unit));
1916 	KASSERT(name != NULL || unit == -1,
1917 	    ("child device with wildcard name and specific unit number"));
1918 
1919 	child = make_device(dev, name, unit);
1920 	if (child == NULL)
1921 		return (child);
1922 	child->order = order;
1923 
1924 	TAILQ_FOREACH(place, &dev->children, link) {
1925 		if (place->order > order)
1926 			break;
1927 	}
1928 
1929 	if (place) {
1930 		/*
1931 		 * The device 'place' is the first device whose order is
1932 		 * greater than the new child.
1933 		 */
1934 		TAILQ_INSERT_BEFORE(place, child, link);
1935 	} else {
1936 		/*
1937 		 * The new child's order is greater or equal to the order of
1938 		 * any existing device. Add the child to the tail of the list.
1939 		 */
1940 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1941 	}
1942 
1943 	bus_data_generation_update();
1944 	return (child);
1945 }
1946 
1947 /**
1948  * @brief Delete a device
1949  *
1950  * This function deletes a device along with all of its children. If
1951  * the device currently has a driver attached to it, the device is
1952  * detached first using device_detach().
1953  *
1954  * @param dev		the parent device
1955  * @param child		the device to delete
1956  *
1957  * @retval 0		success
1958  * @retval non-zero	a unit error code describing the error
1959  */
1960 int
1961 device_delete_child(device_t dev, device_t child)
1962 {
1963 	int error;
1964 	device_t grandchild;
1965 
1966 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1967 
1968 	/* detach parent before deleting children, if any */
1969 	if ((error = device_detach(child)) != 0)
1970 		return (error);
1971 
1972 	/* remove children second */
1973 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1974 		error = device_delete_child(child, grandchild);
1975 		if (error)
1976 			return (error);
1977 	}
1978 
1979 	if (child->devclass)
1980 		devclass_delete_device(child->devclass, child);
1981 	if (child->parent)
1982 		BUS_CHILD_DELETED(dev, child);
1983 	TAILQ_REMOVE(&dev->children, child, link);
1984 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1985 	kobj_delete((kobj_t) child, M_BUS);
1986 
1987 	bus_data_generation_update();
1988 	return (0);
1989 }
1990 
1991 /**
1992  * @brief Delete all children devices of the given device, if any.
1993  *
1994  * This function deletes all children devices of the given device, if
1995  * any, using the device_delete_child() function for each device it
1996  * finds. If a child device cannot be deleted, this function will
1997  * return an error code.
1998  *
1999  * @param dev		the parent device
2000  *
2001  * @retval 0		success
2002  * @retval non-zero	a device would not detach
2003  */
2004 int
2005 device_delete_children(device_t dev)
2006 {
2007 	device_t child;
2008 	int error;
2009 
2010 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2011 
2012 	error = 0;
2013 
2014 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2015 		error = device_delete_child(dev, child);
2016 		if (error) {
2017 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2018 			break;
2019 		}
2020 	}
2021 	return (error);
2022 }
2023 
2024 /**
2025  * @brief Find a device given a unit number
2026  *
2027  * This is similar to devclass_get_devices() but only searches for
2028  * devices which have @p dev as a parent.
2029  *
2030  * @param dev		the parent device to search
2031  * @param unit		the unit number to search for.  If the unit is -1,
2032  *			return the first child of @p dev which has name
2033  *			@p classname (that is, the one with the lowest unit.)
2034  *
2035  * @returns		the device with the given unit number or @c
2036  *			NULL if there is no such device
2037  */
2038 device_t
2039 device_find_child(device_t dev, const char *classname, int unit)
2040 {
2041 	devclass_t dc;
2042 	device_t child;
2043 
2044 	dc = devclass_find(classname);
2045 	if (!dc)
2046 		return (NULL);
2047 
2048 	if (unit != -1) {
2049 		child = devclass_get_device(dc, unit);
2050 		if (child && child->parent == dev)
2051 			return (child);
2052 	} else {
2053 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2054 			child = devclass_get_device(dc, unit);
2055 			if (child && child->parent == dev)
2056 				return (child);
2057 		}
2058 	}
2059 	return (NULL);
2060 }
2061 
2062 /**
2063  * @internal
2064  */
2065 static driverlink_t
2066 first_matching_driver(devclass_t dc, device_t dev)
2067 {
2068 	if (dev->devclass)
2069 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2070 	return (TAILQ_FIRST(&dc->drivers));
2071 }
2072 
2073 /**
2074  * @internal
2075  */
2076 static driverlink_t
2077 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2078 {
2079 	if (dev->devclass) {
2080 		driverlink_t dl;
2081 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2082 			if (!strcmp(dev->devclass->name, dl->driver->name))
2083 				return (dl);
2084 		return (NULL);
2085 	}
2086 	return (TAILQ_NEXT(last, link));
2087 }
2088 
2089 /**
2090  * @internal
2091  */
2092 int
2093 device_probe_child(device_t dev, device_t child)
2094 {
2095 	devclass_t dc;
2096 	driverlink_t best = NULL;
2097 	driverlink_t dl;
2098 	int result, pri = 0;
2099 	int hasclass = (child->devclass != NULL);
2100 
2101 	GIANT_REQUIRED;
2102 
2103 	dc = dev->devclass;
2104 	if (!dc)
2105 		panic("device_probe_child: parent device has no devclass");
2106 
2107 	/*
2108 	 * If the state is already probed, then return.  However, don't
2109 	 * return if we can rebid this object.
2110 	 */
2111 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2112 		return (0);
2113 
2114 	for (; dc; dc = dc->parent) {
2115 		for (dl = first_matching_driver(dc, child);
2116 		     dl;
2117 		     dl = next_matching_driver(dc, child, dl)) {
2118 			/* If this driver's pass is too high, then ignore it. */
2119 			if (dl->pass > bus_current_pass)
2120 				continue;
2121 
2122 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2123 			result = device_set_driver(child, dl->driver);
2124 			if (result == ENOMEM)
2125 				return (result);
2126 			else if (result != 0)
2127 				continue;
2128 			if (!hasclass) {
2129 				if (device_set_devclass(child,
2130 				    dl->driver->name) != 0) {
2131 					char const * devname =
2132 					    device_get_name(child);
2133 					if (devname == NULL)
2134 						devname = "(unknown)";
2135 					printf("driver bug: Unable to set "
2136 					    "devclass (class: %s "
2137 					    "devname: %s)\n",
2138 					    dl->driver->name,
2139 					    devname);
2140 					(void)device_set_driver(child, NULL);
2141 					continue;
2142 				}
2143 			}
2144 
2145 			/* Fetch any flags for the device before probing. */
2146 			resource_int_value(dl->driver->name, child->unit,
2147 			    "flags", &child->devflags);
2148 
2149 			result = DEVICE_PROBE(child);
2150 
2151 			/* Reset flags and devclass before the next probe. */
2152 			child->devflags = 0;
2153 			if (!hasclass)
2154 				(void)device_set_devclass(child, NULL);
2155 
2156 			/*
2157 			 * If the driver returns SUCCESS, there can be
2158 			 * no higher match for this device.
2159 			 */
2160 			if (result == 0) {
2161 				best = dl;
2162 				pri = 0;
2163 				break;
2164 			}
2165 
2166 			/*
2167 			 * Reset DF_QUIET in case this driver doesn't
2168 			 * end up as the best driver.
2169 			 */
2170 			device_verbose(child);
2171 
2172 			/*
2173 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2174 			 * only match on devices whose driver was explicitly
2175 			 * specified.
2176 			 */
2177 			if (result <= BUS_PROBE_NOWILDCARD &&
2178 			    !(child->flags & DF_FIXEDCLASS)) {
2179 				result = ENXIO;
2180 			}
2181 
2182 			/*
2183 			 * The driver returned an error so it
2184 			 * certainly doesn't match.
2185 			 */
2186 			if (result > 0) {
2187 				(void)device_set_driver(child, NULL);
2188 				continue;
2189 			}
2190 
2191 			/*
2192 			 * A priority lower than SUCCESS, remember the
2193 			 * best matching driver. Initialise the value
2194 			 * of pri for the first match.
2195 			 */
2196 			if (best == NULL || result > pri) {
2197 				best = dl;
2198 				pri = result;
2199 				continue;
2200 			}
2201 		}
2202 		/*
2203 		 * If we have an unambiguous match in this devclass,
2204 		 * don't look in the parent.
2205 		 */
2206 		if (best && pri == 0)
2207 			break;
2208 	}
2209 
2210 	/*
2211 	 * If we found a driver, change state and initialise the devclass.
2212 	 */
2213 	/* XXX What happens if we rebid and got no best? */
2214 	if (best) {
2215 		/*
2216 		 * If this device was attached, and we were asked to
2217 		 * rescan, and it is a different driver, then we have
2218 		 * to detach the old driver and reattach this new one.
2219 		 * Note, we don't have to check for DF_REBID here
2220 		 * because if the state is > DS_ALIVE, we know it must
2221 		 * be.
2222 		 *
2223 		 * This assumes that all DF_REBID drivers can have
2224 		 * their probe routine called at any time and that
2225 		 * they are idempotent as well as completely benign in
2226 		 * normal operations.
2227 		 *
2228 		 * We also have to make sure that the detach
2229 		 * succeeded, otherwise we fail the operation (or
2230 		 * maybe it should just fail silently?  I'm torn).
2231 		 */
2232 		if (child->state > DS_ALIVE && best->driver != child->driver)
2233 			if ((result = device_detach(dev)) != 0)
2234 				return (result);
2235 
2236 		/* Set the winning driver, devclass, and flags. */
2237 		if (!child->devclass) {
2238 			result = device_set_devclass(child, best->driver->name);
2239 			if (result != 0)
2240 				return (result);
2241 		}
2242 		result = device_set_driver(child, best->driver);
2243 		if (result != 0)
2244 			return (result);
2245 		resource_int_value(best->driver->name, child->unit,
2246 		    "flags", &child->devflags);
2247 
2248 		if (pri < 0) {
2249 			/*
2250 			 * A bit bogus. Call the probe method again to make
2251 			 * sure that we have the right description.
2252 			 */
2253 			DEVICE_PROBE(child);
2254 #if 0
2255 			child->flags |= DF_REBID;
2256 #endif
2257 		} else
2258 			child->flags &= ~DF_REBID;
2259 		child->state = DS_ALIVE;
2260 
2261 		bus_data_generation_update();
2262 		return (0);
2263 	}
2264 
2265 	return (ENXIO);
2266 }
2267 
2268 /**
2269  * @brief Return the parent of a device
2270  */
2271 device_t
2272 device_get_parent(device_t dev)
2273 {
2274 	return (dev->parent);
2275 }
2276 
2277 /**
2278  * @brief Get a list of children of a device
2279  *
2280  * An array containing a list of all the children of the given device
2281  * is allocated and returned in @p *devlistp. The number of devices
2282  * in the array is returned in @p *devcountp. The caller should free
2283  * the array using @c free(p, M_TEMP).
2284  *
2285  * @param dev		the device to examine
2286  * @param devlistp	points at location for array pointer return
2287  *			value
2288  * @param devcountp	points at location for array size return value
2289  *
2290  * @retval 0		success
2291  * @retval ENOMEM	the array allocation failed
2292  */
2293 int
2294 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2295 {
2296 	int count;
2297 	device_t child;
2298 	device_t *list;
2299 
2300 	count = 0;
2301 	TAILQ_FOREACH(child, &dev->children, link) {
2302 		count++;
2303 	}
2304 	if (count == 0) {
2305 		*devlistp = NULL;
2306 		*devcountp = 0;
2307 		return (0);
2308 	}
2309 
2310 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2311 	if (!list)
2312 		return (ENOMEM);
2313 
2314 	count = 0;
2315 	TAILQ_FOREACH(child, &dev->children, link) {
2316 		list[count] = child;
2317 		count++;
2318 	}
2319 
2320 	*devlistp = list;
2321 	*devcountp = count;
2322 
2323 	return (0);
2324 }
2325 
2326 /**
2327  * @brief Return the current driver for the device or @c NULL if there
2328  * is no driver currently attached
2329  */
2330 driver_t *
2331 device_get_driver(device_t dev)
2332 {
2333 	return (dev->driver);
2334 }
2335 
2336 /**
2337  * @brief Return the current devclass for the device or @c NULL if
2338  * there is none.
2339  */
2340 devclass_t
2341 device_get_devclass(device_t dev)
2342 {
2343 	return (dev->devclass);
2344 }
2345 
2346 /**
2347  * @brief Return the name of the device's devclass or @c NULL if there
2348  * is none.
2349  */
2350 const char *
2351 device_get_name(device_t dev)
2352 {
2353 	if (dev != NULL && dev->devclass)
2354 		return (devclass_get_name(dev->devclass));
2355 	return (NULL);
2356 }
2357 
2358 /**
2359  * @brief Return a string containing the device's devclass name
2360  * followed by an ascii representation of the device's unit number
2361  * (e.g. @c "foo2").
2362  */
2363 const char *
2364 device_get_nameunit(device_t dev)
2365 {
2366 	return (dev->nameunit);
2367 }
2368 
2369 /**
2370  * @brief Return the device's unit number.
2371  */
2372 int
2373 device_get_unit(device_t dev)
2374 {
2375 	return (dev->unit);
2376 }
2377 
2378 /**
2379  * @brief Return the device's description string
2380  */
2381 const char *
2382 device_get_desc(device_t dev)
2383 {
2384 	return (dev->desc);
2385 }
2386 
2387 /**
2388  * @brief Return the device's flags
2389  */
2390 uint32_t
2391 device_get_flags(device_t dev)
2392 {
2393 	return (dev->devflags);
2394 }
2395 
2396 struct sysctl_ctx_list *
2397 device_get_sysctl_ctx(device_t dev)
2398 {
2399 	return (&dev->sysctl_ctx);
2400 }
2401 
2402 struct sysctl_oid *
2403 device_get_sysctl_tree(device_t dev)
2404 {
2405 	return (dev->sysctl_tree);
2406 }
2407 
2408 /**
2409  * @brief Print the name of the device followed by a colon and a space
2410  *
2411  * @returns the number of characters printed
2412  */
2413 int
2414 device_print_prettyname(device_t dev)
2415 {
2416 	const char *name = device_get_name(dev);
2417 
2418 	if (name == NULL)
2419 		return (printf("unknown: "));
2420 	return (printf("%s%d: ", name, device_get_unit(dev)));
2421 }
2422 
2423 /**
2424  * @brief Print the name of the device followed by a colon, a space
2425  * and the result of calling vprintf() with the value of @p fmt and
2426  * the following arguments.
2427  *
2428  * @returns the number of characters printed
2429  */
2430 int
2431 device_printf(device_t dev, const char * fmt, ...)
2432 {
2433 	char buf[128];
2434 	struct sbuf sb;
2435 	const char *name;
2436 	va_list ap;
2437 	size_t retval;
2438 
2439 	retval = 0;
2440 
2441 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2442 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2443 
2444 	name = device_get_name(dev);
2445 
2446 	if (name == NULL)
2447 		sbuf_cat(&sb, "unknown: ");
2448 	else
2449 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2450 
2451 	va_start(ap, fmt);
2452 	sbuf_vprintf(&sb, fmt, ap);
2453 	va_end(ap);
2454 
2455 	sbuf_finish(&sb);
2456 	sbuf_delete(&sb);
2457 
2458 	return (retval);
2459 }
2460 
2461 /**
2462  * @internal
2463  */
2464 static void
2465 device_set_desc_internal(device_t dev, const char* desc, int copy)
2466 {
2467 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2468 		free(dev->desc, M_BUS);
2469 		dev->flags &= ~DF_DESCMALLOCED;
2470 		dev->desc = NULL;
2471 	}
2472 
2473 	if (copy && desc) {
2474 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2475 		if (dev->desc) {
2476 			strcpy(dev->desc, desc);
2477 			dev->flags |= DF_DESCMALLOCED;
2478 		}
2479 	} else {
2480 		/* Avoid a -Wcast-qual warning */
2481 		dev->desc = (char *)(uintptr_t) desc;
2482 	}
2483 
2484 	bus_data_generation_update();
2485 }
2486 
2487 /**
2488  * @brief Set the device's description
2489  *
2490  * The value of @c desc should be a string constant that will not
2491  * change (at least until the description is changed in a subsequent
2492  * call to device_set_desc() or device_set_desc_copy()).
2493  */
2494 void
2495 device_set_desc(device_t dev, const char* desc)
2496 {
2497 	device_set_desc_internal(dev, desc, FALSE);
2498 }
2499 
2500 /**
2501  * @brief Set the device's description
2502  *
2503  * The string pointed to by @c desc is copied. Use this function if
2504  * the device description is generated, (e.g. with sprintf()).
2505  */
2506 void
2507 device_set_desc_copy(device_t dev, const char* desc)
2508 {
2509 	device_set_desc_internal(dev, desc, TRUE);
2510 }
2511 
2512 /**
2513  * @brief Set the device's flags
2514  */
2515 void
2516 device_set_flags(device_t dev, uint32_t flags)
2517 {
2518 	dev->devflags = flags;
2519 }
2520 
2521 /**
2522  * @brief Return the device's softc field
2523  *
2524  * The softc is allocated and zeroed when a driver is attached, based
2525  * on the size field of the driver.
2526  */
2527 void *
2528 device_get_softc(device_t dev)
2529 {
2530 	return (dev->softc);
2531 }
2532 
2533 /**
2534  * @brief Set the device's softc field
2535  *
2536  * Most drivers do not need to use this since the softc is allocated
2537  * automatically when the driver is attached.
2538  */
2539 void
2540 device_set_softc(device_t dev, void *softc)
2541 {
2542 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2543 		free(dev->softc, M_BUS_SC);
2544 	dev->softc = softc;
2545 	if (dev->softc)
2546 		dev->flags |= DF_EXTERNALSOFTC;
2547 	else
2548 		dev->flags &= ~DF_EXTERNALSOFTC;
2549 }
2550 
2551 /**
2552  * @brief Free claimed softc
2553  *
2554  * Most drivers do not need to use this since the softc is freed
2555  * automatically when the driver is detached.
2556  */
2557 void
2558 device_free_softc(void *softc)
2559 {
2560 	free(softc, M_BUS_SC);
2561 }
2562 
2563 /**
2564  * @brief Claim softc
2565  *
2566  * This function can be used to let the driver free the automatically
2567  * allocated softc using "device_free_softc()". This function is
2568  * useful when the driver is refcounting the softc and the softc
2569  * cannot be freed when the "device_detach" method is called.
2570  */
2571 void
2572 device_claim_softc(device_t dev)
2573 {
2574 	if (dev->softc)
2575 		dev->flags |= DF_EXTERNALSOFTC;
2576 	else
2577 		dev->flags &= ~DF_EXTERNALSOFTC;
2578 }
2579 
2580 /**
2581  * @brief Get the device's ivars field
2582  *
2583  * The ivars field is used by the parent device to store per-device
2584  * state (e.g. the physical location of the device or a list of
2585  * resources).
2586  */
2587 void *
2588 device_get_ivars(device_t dev)
2589 {
2590 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2591 	return (dev->ivars);
2592 }
2593 
2594 /**
2595  * @brief Set the device's ivars field
2596  */
2597 void
2598 device_set_ivars(device_t dev, void * ivars)
2599 {
2600 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2601 	dev->ivars = ivars;
2602 }
2603 
2604 /**
2605  * @brief Return the device's state
2606  */
2607 device_state_t
2608 device_get_state(device_t dev)
2609 {
2610 	return (dev->state);
2611 }
2612 
2613 /**
2614  * @brief Set the DF_ENABLED flag for the device
2615  */
2616 void
2617 device_enable(device_t dev)
2618 {
2619 	dev->flags |= DF_ENABLED;
2620 }
2621 
2622 /**
2623  * @brief Clear the DF_ENABLED flag for the device
2624  */
2625 void
2626 device_disable(device_t dev)
2627 {
2628 	dev->flags &= ~DF_ENABLED;
2629 }
2630 
2631 /**
2632  * @brief Increment the busy counter for the device
2633  */
2634 void
2635 device_busy(device_t dev)
2636 {
2637 	if (dev->state < DS_ATTACHING)
2638 		panic("device_busy: called for unattached device");
2639 	if (dev->busy == 0 && dev->parent)
2640 		device_busy(dev->parent);
2641 	dev->busy++;
2642 	if (dev->state == DS_ATTACHED)
2643 		dev->state = DS_BUSY;
2644 }
2645 
2646 /**
2647  * @brief Decrement the busy counter for the device
2648  */
2649 void
2650 device_unbusy(device_t dev)
2651 {
2652 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2653 	    dev->state != DS_ATTACHING)
2654 		panic("device_unbusy: called for non-busy device %s",
2655 		    device_get_nameunit(dev));
2656 	dev->busy--;
2657 	if (dev->busy == 0) {
2658 		if (dev->parent)
2659 			device_unbusy(dev->parent);
2660 		if (dev->state == DS_BUSY)
2661 			dev->state = DS_ATTACHED;
2662 	}
2663 }
2664 
2665 /**
2666  * @brief Set the DF_QUIET flag for the device
2667  */
2668 void
2669 device_quiet(device_t dev)
2670 {
2671 	dev->flags |= DF_QUIET;
2672 }
2673 
2674 /**
2675  * @brief Set the DF_QUIET_CHILDREN flag for the device
2676  */
2677 void
2678 device_quiet_children(device_t dev)
2679 {
2680 	dev->flags |= DF_QUIET_CHILDREN;
2681 }
2682 
2683 /**
2684  * @brief Clear the DF_QUIET flag for the device
2685  */
2686 void
2687 device_verbose(device_t dev)
2688 {
2689 	dev->flags &= ~DF_QUIET;
2690 }
2691 
2692 /**
2693  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2694  */
2695 int
2696 device_has_quiet_children(device_t dev)
2697 {
2698 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2699 }
2700 
2701 /**
2702  * @brief Return non-zero if the DF_QUIET flag is set on the device
2703  */
2704 int
2705 device_is_quiet(device_t dev)
2706 {
2707 	return ((dev->flags & DF_QUIET) != 0);
2708 }
2709 
2710 /**
2711  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2712  */
2713 int
2714 device_is_enabled(device_t dev)
2715 {
2716 	return ((dev->flags & DF_ENABLED) != 0);
2717 }
2718 
2719 /**
2720  * @brief Return non-zero if the device was successfully probed
2721  */
2722 int
2723 device_is_alive(device_t dev)
2724 {
2725 	return (dev->state >= DS_ALIVE);
2726 }
2727 
2728 /**
2729  * @brief Return non-zero if the device currently has a driver
2730  * attached to it
2731  */
2732 int
2733 device_is_attached(device_t dev)
2734 {
2735 	return (dev->state >= DS_ATTACHED);
2736 }
2737 
2738 /**
2739  * @brief Return non-zero if the device is currently suspended.
2740  */
2741 int
2742 device_is_suspended(device_t dev)
2743 {
2744 	return ((dev->flags & DF_SUSPENDED) != 0);
2745 }
2746 
2747 /**
2748  * @brief Set the devclass of a device
2749  * @see devclass_add_device().
2750  */
2751 int
2752 device_set_devclass(device_t dev, const char *classname)
2753 {
2754 	devclass_t dc;
2755 	int error;
2756 
2757 	if (!classname) {
2758 		if (dev->devclass)
2759 			devclass_delete_device(dev->devclass, dev);
2760 		return (0);
2761 	}
2762 
2763 	if (dev->devclass) {
2764 		printf("device_set_devclass: device class already set\n");
2765 		return (EINVAL);
2766 	}
2767 
2768 	dc = devclass_find_internal(classname, NULL, TRUE);
2769 	if (!dc)
2770 		return (ENOMEM);
2771 
2772 	error = devclass_add_device(dc, dev);
2773 
2774 	bus_data_generation_update();
2775 	return (error);
2776 }
2777 
2778 /**
2779  * @brief Set the devclass of a device and mark the devclass fixed.
2780  * @see device_set_devclass()
2781  */
2782 int
2783 device_set_devclass_fixed(device_t dev, const char *classname)
2784 {
2785 	int error;
2786 
2787 	if (classname == NULL)
2788 		return (EINVAL);
2789 
2790 	error = device_set_devclass(dev, classname);
2791 	if (error)
2792 		return (error);
2793 	dev->flags |= DF_FIXEDCLASS;
2794 	return (0);
2795 }
2796 
2797 /**
2798  * @brief Query the device to determine if it's of a fixed devclass
2799  * @see device_set_devclass_fixed()
2800  */
2801 bool
2802 device_is_devclass_fixed(device_t dev)
2803 {
2804 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2805 }
2806 
2807 /**
2808  * @brief Set the driver of a device
2809  *
2810  * @retval 0		success
2811  * @retval EBUSY	the device already has a driver attached
2812  * @retval ENOMEM	a memory allocation failure occurred
2813  */
2814 int
2815 device_set_driver(device_t dev, driver_t *driver)
2816 {
2817 	int domain;
2818 	struct domainset *policy;
2819 
2820 	if (dev->state >= DS_ATTACHED)
2821 		return (EBUSY);
2822 
2823 	if (dev->driver == driver)
2824 		return (0);
2825 
2826 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2827 		free(dev->softc, M_BUS_SC);
2828 		dev->softc = NULL;
2829 	}
2830 	device_set_desc(dev, NULL);
2831 	kobj_delete((kobj_t) dev, NULL);
2832 	dev->driver = driver;
2833 	if (driver) {
2834 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2835 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2836 			if (bus_get_domain(dev, &domain) == 0)
2837 				policy = DOMAINSET_PREF(domain);
2838 			else
2839 				policy = DOMAINSET_RR();
2840 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2841 			    policy, M_NOWAIT | M_ZERO);
2842 			if (!dev->softc) {
2843 				kobj_delete((kobj_t) dev, NULL);
2844 				kobj_init((kobj_t) dev, &null_class);
2845 				dev->driver = NULL;
2846 				return (ENOMEM);
2847 			}
2848 		}
2849 	} else {
2850 		kobj_init((kobj_t) dev, &null_class);
2851 	}
2852 
2853 	bus_data_generation_update();
2854 	return (0);
2855 }
2856 
2857 /**
2858  * @brief Probe a device, and return this status.
2859  *
2860  * This function is the core of the device autoconfiguration
2861  * system. Its purpose is to select a suitable driver for a device and
2862  * then call that driver to initialise the hardware appropriately. The
2863  * driver is selected by calling the DEVICE_PROBE() method of a set of
2864  * candidate drivers and then choosing the driver which returned the
2865  * best value. This driver is then attached to the device using
2866  * device_attach().
2867  *
2868  * The set of suitable drivers is taken from the list of drivers in
2869  * the parent device's devclass. If the device was originally created
2870  * with a specific class name (see device_add_child()), only drivers
2871  * with that name are probed, otherwise all drivers in the devclass
2872  * are probed. If no drivers return successful probe values in the
2873  * parent devclass, the search continues in the parent of that
2874  * devclass (see devclass_get_parent()) if any.
2875  *
2876  * @param dev		the device to initialise
2877  *
2878  * @retval 0		success
2879  * @retval ENXIO	no driver was found
2880  * @retval ENOMEM	memory allocation failure
2881  * @retval non-zero	some other unix error code
2882  * @retval -1		Device already attached
2883  */
2884 int
2885 device_probe(device_t dev)
2886 {
2887 	int error;
2888 
2889 	GIANT_REQUIRED;
2890 
2891 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2892 		return (-1);
2893 
2894 	if (!(dev->flags & DF_ENABLED)) {
2895 		if (bootverbose && device_get_name(dev) != NULL) {
2896 			device_print_prettyname(dev);
2897 			printf("not probed (disabled)\n");
2898 		}
2899 		return (-1);
2900 	}
2901 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2902 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2903 		    !(dev->flags & DF_DONENOMATCH)) {
2904 			BUS_PROBE_NOMATCH(dev->parent, dev);
2905 			devnomatch(dev);
2906 			dev->flags |= DF_DONENOMATCH;
2907 		}
2908 		return (error);
2909 	}
2910 	return (0);
2911 }
2912 
2913 /**
2914  * @brief Probe a device and attach a driver if possible
2915  *
2916  * calls device_probe() and attaches if that was successful.
2917  */
2918 int
2919 device_probe_and_attach(device_t dev)
2920 {
2921 	int error;
2922 
2923 	GIANT_REQUIRED;
2924 
2925 	error = device_probe(dev);
2926 	if (error == -1)
2927 		return (0);
2928 	else if (error != 0)
2929 		return (error);
2930 
2931 	CURVNET_SET_QUIET(vnet0);
2932 	error = device_attach(dev);
2933 	CURVNET_RESTORE();
2934 	return error;
2935 }
2936 
2937 /**
2938  * @brief Attach a device driver to a device
2939  *
2940  * This function is a wrapper around the DEVICE_ATTACH() driver
2941  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2942  * device's sysctl tree, optionally prints a description of the device
2943  * and queues a notification event for user-based device management
2944  * services.
2945  *
2946  * Normally this function is only called internally from
2947  * device_probe_and_attach().
2948  *
2949  * @param dev		the device to initialise
2950  *
2951  * @retval 0		success
2952  * @retval ENXIO	no driver was found
2953  * @retval ENOMEM	memory allocation failure
2954  * @retval non-zero	some other unix error code
2955  */
2956 int
2957 device_attach(device_t dev)
2958 {
2959 	uint64_t attachtime;
2960 	uint16_t attachentropy;
2961 	int error;
2962 
2963 	if (resource_disabled(dev->driver->name, dev->unit)) {
2964 		device_disable(dev);
2965 		if (bootverbose)
2966 			 device_printf(dev, "disabled via hints entry\n");
2967 		return (ENXIO);
2968 	}
2969 
2970 	device_sysctl_init(dev);
2971 	if (!device_is_quiet(dev))
2972 		device_print_child(dev->parent, dev);
2973 	attachtime = get_cyclecount();
2974 	dev->state = DS_ATTACHING;
2975 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2976 		printf("device_attach: %s%d attach returned %d\n",
2977 		    dev->driver->name, dev->unit, error);
2978 		if (!(dev->flags & DF_FIXEDCLASS))
2979 			devclass_delete_device(dev->devclass, dev);
2980 		(void)device_set_driver(dev, NULL);
2981 		device_sysctl_fini(dev);
2982 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2983 		dev->state = DS_NOTPRESENT;
2984 		return (error);
2985 	}
2986 	dev->flags |= DF_ATTACHED_ONCE;
2987 	/* We only need the low bits of this time, but ranges from tens to thousands
2988 	 * have been seen, so keep 2 bytes' worth.
2989 	 */
2990 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
2991 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
2992 	device_sysctl_update(dev);
2993 	if (dev->busy)
2994 		dev->state = DS_BUSY;
2995 	else
2996 		dev->state = DS_ATTACHED;
2997 	dev->flags &= ~DF_DONENOMATCH;
2998 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
2999 	devadded(dev);
3000 	return (0);
3001 }
3002 
3003 /**
3004  * @brief Detach a driver from a device
3005  *
3006  * This function is a wrapper around the DEVICE_DETACH() driver
3007  * method. If the call to DEVICE_DETACH() succeeds, it calls
3008  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3009  * notification event for user-based device management services and
3010  * cleans up the device's sysctl tree.
3011  *
3012  * @param dev		the device to un-initialise
3013  *
3014  * @retval 0		success
3015  * @retval ENXIO	no driver was found
3016  * @retval ENOMEM	memory allocation failure
3017  * @retval non-zero	some other unix error code
3018  */
3019 int
3020 device_detach(device_t dev)
3021 {
3022 	int error;
3023 
3024 	GIANT_REQUIRED;
3025 
3026 	PDEBUG(("%s", DEVICENAME(dev)));
3027 	if (dev->state == DS_BUSY)
3028 		return (EBUSY);
3029 	if (dev->state == DS_ATTACHING) {
3030 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3031 		return (EBUSY);
3032 	}
3033 	if (dev->state != DS_ATTACHED)
3034 		return (0);
3035 
3036 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3037 	if ((error = DEVICE_DETACH(dev)) != 0) {
3038 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3039 		    EVHDEV_DETACH_FAILED);
3040 		return (error);
3041 	} else {
3042 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3043 		    EVHDEV_DETACH_COMPLETE);
3044 	}
3045 	devremoved(dev);
3046 	if (!device_is_quiet(dev))
3047 		device_printf(dev, "detached\n");
3048 	if (dev->parent)
3049 		BUS_CHILD_DETACHED(dev->parent, dev);
3050 
3051 	if (!(dev->flags & DF_FIXEDCLASS))
3052 		devclass_delete_device(dev->devclass, dev);
3053 
3054 	device_verbose(dev);
3055 	dev->state = DS_NOTPRESENT;
3056 	(void)device_set_driver(dev, NULL);
3057 	device_sysctl_fini(dev);
3058 
3059 	return (0);
3060 }
3061 
3062 /**
3063  * @brief Tells a driver to quiesce itself.
3064  *
3065  * This function is a wrapper around the DEVICE_QUIESCE() driver
3066  * method. If the call to DEVICE_QUIESCE() succeeds.
3067  *
3068  * @param dev		the device to quiesce
3069  *
3070  * @retval 0		success
3071  * @retval ENXIO	no driver was found
3072  * @retval ENOMEM	memory allocation failure
3073  * @retval non-zero	some other unix error code
3074  */
3075 int
3076 device_quiesce(device_t dev)
3077 {
3078 	PDEBUG(("%s", DEVICENAME(dev)));
3079 	if (dev->state == DS_BUSY)
3080 		return (EBUSY);
3081 	if (dev->state != DS_ATTACHED)
3082 		return (0);
3083 
3084 	return (DEVICE_QUIESCE(dev));
3085 }
3086 
3087 /**
3088  * @brief Notify a device of system shutdown
3089  *
3090  * This function calls the DEVICE_SHUTDOWN() driver method if the
3091  * device currently has an attached driver.
3092  *
3093  * @returns the value returned by DEVICE_SHUTDOWN()
3094  */
3095 int
3096 device_shutdown(device_t dev)
3097 {
3098 	if (dev->state < DS_ATTACHED)
3099 		return (0);
3100 	return (DEVICE_SHUTDOWN(dev));
3101 }
3102 
3103 /**
3104  * @brief Set the unit number of a device
3105  *
3106  * This function can be used to override the unit number used for a
3107  * device (e.g. to wire a device to a pre-configured unit number).
3108  */
3109 int
3110 device_set_unit(device_t dev, int unit)
3111 {
3112 	devclass_t dc;
3113 	int err;
3114 
3115 	dc = device_get_devclass(dev);
3116 	if (unit < dc->maxunit && dc->devices[unit])
3117 		return (EBUSY);
3118 	err = devclass_delete_device(dc, dev);
3119 	if (err)
3120 		return (err);
3121 	dev->unit = unit;
3122 	err = devclass_add_device(dc, dev);
3123 	if (err)
3124 		return (err);
3125 
3126 	bus_data_generation_update();
3127 	return (0);
3128 }
3129 
3130 /*======================================*/
3131 /*
3132  * Some useful method implementations to make life easier for bus drivers.
3133  */
3134 
3135 void
3136 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3137 {
3138 	bzero(args, sz);
3139 	args->size = sz;
3140 	args->memattr = VM_MEMATTR_UNCACHEABLE;
3141 }
3142 
3143 /**
3144  * @brief Initialise a resource list.
3145  *
3146  * @param rl		the resource list to initialise
3147  */
3148 void
3149 resource_list_init(struct resource_list *rl)
3150 {
3151 	STAILQ_INIT(rl);
3152 }
3153 
3154 /**
3155  * @brief Reclaim memory used by a resource list.
3156  *
3157  * This function frees the memory for all resource entries on the list
3158  * (if any).
3159  *
3160  * @param rl		the resource list to free
3161  */
3162 void
3163 resource_list_free(struct resource_list *rl)
3164 {
3165 	struct resource_list_entry *rle;
3166 
3167 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3168 		if (rle->res)
3169 			panic("resource_list_free: resource entry is busy");
3170 		STAILQ_REMOVE_HEAD(rl, link);
3171 		free(rle, M_BUS);
3172 	}
3173 }
3174 
3175 /**
3176  * @brief Add a resource entry.
3177  *
3178  * This function adds a resource entry using the given @p type, @p
3179  * start, @p end and @p count values. A rid value is chosen by
3180  * searching sequentially for the first unused rid starting at zero.
3181  *
3182  * @param rl		the resource list to edit
3183  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3184  * @param start		the start address of the resource
3185  * @param end		the end address of the resource
3186  * @param count		XXX end-start+1
3187  */
3188 int
3189 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3190     rman_res_t end, rman_res_t count)
3191 {
3192 	int rid;
3193 
3194 	rid = 0;
3195 	while (resource_list_find(rl, type, rid) != NULL)
3196 		rid++;
3197 	resource_list_add(rl, type, rid, start, end, count);
3198 	return (rid);
3199 }
3200 
3201 /**
3202  * @brief Add or modify a resource entry.
3203  *
3204  * If an existing entry exists with the same type and rid, it will be
3205  * modified using the given values of @p start, @p end and @p
3206  * count. If no entry exists, a new one will be created using the
3207  * given values.  The resource list entry that matches is then returned.
3208  *
3209  * @param rl		the resource list to edit
3210  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3211  * @param rid		the resource identifier
3212  * @param start		the start address of the resource
3213  * @param end		the end address of the resource
3214  * @param count		XXX end-start+1
3215  */
3216 struct resource_list_entry *
3217 resource_list_add(struct resource_list *rl, int type, int rid,
3218     rman_res_t start, rman_res_t end, rman_res_t count)
3219 {
3220 	struct resource_list_entry *rle;
3221 
3222 	rle = resource_list_find(rl, type, rid);
3223 	if (!rle) {
3224 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3225 		    M_NOWAIT);
3226 		if (!rle)
3227 			panic("resource_list_add: can't record entry");
3228 		STAILQ_INSERT_TAIL(rl, rle, link);
3229 		rle->type = type;
3230 		rle->rid = rid;
3231 		rle->res = NULL;
3232 		rle->flags = 0;
3233 	}
3234 
3235 	if (rle->res)
3236 		panic("resource_list_add: resource entry is busy");
3237 
3238 	rle->start = start;
3239 	rle->end = end;
3240 	rle->count = count;
3241 	return (rle);
3242 }
3243 
3244 /**
3245  * @brief Determine if a resource entry is busy.
3246  *
3247  * Returns true if a resource entry is busy meaning that it has an
3248  * associated resource that is not an unallocated "reserved" resource.
3249  *
3250  * @param rl		the resource list to search
3251  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3252  * @param rid		the resource identifier
3253  *
3254  * @returns Non-zero if the entry is busy, zero otherwise.
3255  */
3256 int
3257 resource_list_busy(struct resource_list *rl, int type, int rid)
3258 {
3259 	struct resource_list_entry *rle;
3260 
3261 	rle = resource_list_find(rl, type, rid);
3262 	if (rle == NULL || rle->res == NULL)
3263 		return (0);
3264 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3265 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3266 		    ("reserved resource is active"));
3267 		return (0);
3268 	}
3269 	return (1);
3270 }
3271 
3272 /**
3273  * @brief Determine if a resource entry is reserved.
3274  *
3275  * Returns true if a resource entry is reserved meaning that it has an
3276  * associated "reserved" resource.  The resource can either be
3277  * allocated or unallocated.
3278  *
3279  * @param rl		the resource list to search
3280  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3281  * @param rid		the resource identifier
3282  *
3283  * @returns Non-zero if the entry is reserved, zero otherwise.
3284  */
3285 int
3286 resource_list_reserved(struct resource_list *rl, int type, int rid)
3287 {
3288 	struct resource_list_entry *rle;
3289 
3290 	rle = resource_list_find(rl, type, rid);
3291 	if (rle != NULL && rle->flags & RLE_RESERVED)
3292 		return (1);
3293 	return (0);
3294 }
3295 
3296 /**
3297  * @brief Find a resource entry by type and rid.
3298  *
3299  * @param rl		the resource list to search
3300  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3301  * @param rid		the resource identifier
3302  *
3303  * @returns the resource entry pointer or NULL if there is no such
3304  * entry.
3305  */
3306 struct resource_list_entry *
3307 resource_list_find(struct resource_list *rl, int type, int rid)
3308 {
3309 	struct resource_list_entry *rle;
3310 
3311 	STAILQ_FOREACH(rle, rl, link) {
3312 		if (rle->type == type && rle->rid == rid)
3313 			return (rle);
3314 	}
3315 	return (NULL);
3316 }
3317 
3318 /**
3319  * @brief Delete a resource entry.
3320  *
3321  * @param rl		the resource list to edit
3322  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3323  * @param rid		the resource identifier
3324  */
3325 void
3326 resource_list_delete(struct resource_list *rl, int type, int rid)
3327 {
3328 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3329 
3330 	if (rle) {
3331 		if (rle->res != NULL)
3332 			panic("resource_list_delete: resource has not been released");
3333 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3334 		free(rle, M_BUS);
3335 	}
3336 }
3337 
3338 /**
3339  * @brief Allocate a reserved resource
3340  *
3341  * This can be used by buses to force the allocation of resources
3342  * that are always active in the system even if they are not allocated
3343  * by a driver (e.g. PCI BARs).  This function is usually called when
3344  * adding a new child to the bus.  The resource is allocated from the
3345  * parent bus when it is reserved.  The resource list entry is marked
3346  * with RLE_RESERVED to note that it is a reserved resource.
3347  *
3348  * Subsequent attempts to allocate the resource with
3349  * resource_list_alloc() will succeed the first time and will set
3350  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3351  * resource that has been allocated is released with
3352  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3353  * the actual resource remains allocated.  The resource can be released to
3354  * the parent bus by calling resource_list_unreserve().
3355  *
3356  * @param rl		the resource list to allocate from
3357  * @param bus		the parent device of @p child
3358  * @param child		the device for which the resource is being reserved
3359  * @param type		the type of resource to allocate
3360  * @param rid		a pointer to the resource identifier
3361  * @param start		hint at the start of the resource range - pass
3362  *			@c 0 for any start address
3363  * @param end		hint at the end of the resource range - pass
3364  *			@c ~0 for any end address
3365  * @param count		hint at the size of range required - pass @c 1
3366  *			for any size
3367  * @param flags		any extra flags to control the resource
3368  *			allocation - see @c RF_XXX flags in
3369  *			<sys/rman.h> for details
3370  *
3371  * @returns		the resource which was allocated or @c NULL if no
3372  *			resource could be allocated
3373  */
3374 struct resource *
3375 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3376     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3377 {
3378 	struct resource_list_entry *rle = NULL;
3379 	int passthrough = (device_get_parent(child) != bus);
3380 	struct resource *r;
3381 
3382 	if (passthrough)
3383 		panic(
3384     "resource_list_reserve() should only be called for direct children");
3385 	if (flags & RF_ACTIVE)
3386 		panic(
3387     "resource_list_reserve() should only reserve inactive resources");
3388 
3389 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3390 	    flags);
3391 	if (r != NULL) {
3392 		rle = resource_list_find(rl, type, *rid);
3393 		rle->flags |= RLE_RESERVED;
3394 	}
3395 	return (r);
3396 }
3397 
3398 /**
3399  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3400  *
3401  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3402  * and passing the allocation up to the parent of @p bus. This assumes
3403  * that the first entry of @c device_get_ivars(child) is a struct
3404  * resource_list. This also handles 'passthrough' allocations where a
3405  * child is a remote descendant of bus by passing the allocation up to
3406  * the parent of bus.
3407  *
3408  * Typically, a bus driver would store a list of child resources
3409  * somewhere in the child device's ivars (see device_get_ivars()) and
3410  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3411  * then call resource_list_alloc() to perform the allocation.
3412  *
3413  * @param rl		the resource list to allocate from
3414  * @param bus		the parent device of @p child
3415  * @param child		the device which is requesting an allocation
3416  * @param type		the type of resource to allocate
3417  * @param rid		a pointer to the resource identifier
3418  * @param start		hint at the start of the resource range - pass
3419  *			@c 0 for any start address
3420  * @param end		hint at the end of the resource range - pass
3421  *			@c ~0 for any end address
3422  * @param count		hint at the size of range required - pass @c 1
3423  *			for any size
3424  * @param flags		any extra flags to control the resource
3425  *			allocation - see @c RF_XXX flags in
3426  *			<sys/rman.h> for details
3427  *
3428  * @returns		the resource which was allocated or @c NULL if no
3429  *			resource could be allocated
3430  */
3431 struct resource *
3432 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3433     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3434 {
3435 	struct resource_list_entry *rle = NULL;
3436 	int passthrough = (device_get_parent(child) != bus);
3437 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3438 
3439 	if (passthrough) {
3440 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3441 		    type, rid, start, end, count, flags));
3442 	}
3443 
3444 	rle = resource_list_find(rl, type, *rid);
3445 
3446 	if (!rle)
3447 		return (NULL);		/* no resource of that type/rid */
3448 
3449 	if (rle->res) {
3450 		if (rle->flags & RLE_RESERVED) {
3451 			if (rle->flags & RLE_ALLOCATED)
3452 				return (NULL);
3453 			if ((flags & RF_ACTIVE) &&
3454 			    bus_activate_resource(child, type, *rid,
3455 			    rle->res) != 0)
3456 				return (NULL);
3457 			rle->flags |= RLE_ALLOCATED;
3458 			return (rle->res);
3459 		}
3460 		device_printf(bus,
3461 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3462 		    type, device_get_nameunit(child));
3463 		return (NULL);
3464 	}
3465 
3466 	if (isdefault) {
3467 		start = rle->start;
3468 		count = ulmax(count, rle->count);
3469 		end = ulmax(rle->end, start + count - 1);
3470 	}
3471 
3472 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3473 	    type, rid, start, end, count, flags);
3474 
3475 	/*
3476 	 * Record the new range.
3477 	 */
3478 	if (rle->res) {
3479 		rle->start = rman_get_start(rle->res);
3480 		rle->end = rman_get_end(rle->res);
3481 		rle->count = count;
3482 	}
3483 
3484 	return (rle->res);
3485 }
3486 
3487 /**
3488  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3489  *
3490  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3491  * used with resource_list_alloc().
3492  *
3493  * @param rl		the resource list which was allocated from
3494  * @param bus		the parent device of @p child
3495  * @param child		the device which is requesting a release
3496  * @param type		the type of resource to release
3497  * @param rid		the resource identifier
3498  * @param res		the resource to release
3499  *
3500  * @retval 0		success
3501  * @retval non-zero	a standard unix error code indicating what
3502  *			error condition prevented the operation
3503  */
3504 int
3505 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3506     int type, int rid, struct resource *res)
3507 {
3508 	struct resource_list_entry *rle = NULL;
3509 	int passthrough = (device_get_parent(child) != bus);
3510 	int error;
3511 
3512 	if (passthrough) {
3513 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3514 		    type, rid, res));
3515 	}
3516 
3517 	rle = resource_list_find(rl, type, rid);
3518 
3519 	if (!rle)
3520 		panic("resource_list_release: can't find resource");
3521 	if (!rle->res)
3522 		panic("resource_list_release: resource entry is not busy");
3523 	if (rle->flags & RLE_RESERVED) {
3524 		if (rle->flags & RLE_ALLOCATED) {
3525 			if (rman_get_flags(res) & RF_ACTIVE) {
3526 				error = bus_deactivate_resource(child, type,
3527 				    rid, res);
3528 				if (error)
3529 					return (error);
3530 			}
3531 			rle->flags &= ~RLE_ALLOCATED;
3532 			return (0);
3533 		}
3534 		return (EINVAL);
3535 	}
3536 
3537 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3538 	    type, rid, res);
3539 	if (error)
3540 		return (error);
3541 
3542 	rle->res = NULL;
3543 	return (0);
3544 }
3545 
3546 /**
3547  * @brief Release all active resources of a given type
3548  *
3549  * Release all active resources of a specified type.  This is intended
3550  * to be used to cleanup resources leaked by a driver after detach or
3551  * a failed attach.
3552  *
3553  * @param rl		the resource list which was allocated from
3554  * @param bus		the parent device of @p child
3555  * @param child		the device whose active resources are being released
3556  * @param type		the type of resources to release
3557  *
3558  * @retval 0		success
3559  * @retval EBUSY	at least one resource was active
3560  */
3561 int
3562 resource_list_release_active(struct resource_list *rl, device_t bus,
3563     device_t child, int type)
3564 {
3565 	struct resource_list_entry *rle;
3566 	int error, retval;
3567 
3568 	retval = 0;
3569 	STAILQ_FOREACH(rle, rl, link) {
3570 		if (rle->type != type)
3571 			continue;
3572 		if (rle->res == NULL)
3573 			continue;
3574 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3575 		    RLE_RESERVED)
3576 			continue;
3577 		retval = EBUSY;
3578 		error = resource_list_release(rl, bus, child, type,
3579 		    rman_get_rid(rle->res), rle->res);
3580 		if (error != 0)
3581 			device_printf(bus,
3582 			    "Failed to release active resource: %d\n", error);
3583 	}
3584 	return (retval);
3585 }
3586 
3587 /**
3588  * @brief Fully release a reserved resource
3589  *
3590  * Fully releases a resource reserved via resource_list_reserve().
3591  *
3592  * @param rl		the resource list which was allocated from
3593  * @param bus		the parent device of @p child
3594  * @param child		the device whose reserved resource is being released
3595  * @param type		the type of resource to release
3596  * @param rid		the resource identifier
3597  * @param res		the resource to release
3598  *
3599  * @retval 0		success
3600  * @retval non-zero	a standard unix error code indicating what
3601  *			error condition prevented the operation
3602  */
3603 int
3604 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3605     int type, int rid)
3606 {
3607 	struct resource_list_entry *rle = NULL;
3608 	int passthrough = (device_get_parent(child) != bus);
3609 
3610 	if (passthrough)
3611 		panic(
3612     "resource_list_unreserve() should only be called for direct children");
3613 
3614 	rle = resource_list_find(rl, type, rid);
3615 
3616 	if (!rle)
3617 		panic("resource_list_unreserve: can't find resource");
3618 	if (!(rle->flags & RLE_RESERVED))
3619 		return (EINVAL);
3620 	if (rle->flags & RLE_ALLOCATED)
3621 		return (EBUSY);
3622 	rle->flags &= ~RLE_RESERVED;
3623 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3624 }
3625 
3626 /**
3627  * @brief Print a description of resources in a resource list
3628  *
3629  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3630  * The name is printed if at least one resource of the given type is available.
3631  * The format is used to print resource start and end.
3632  *
3633  * @param rl		the resource list to print
3634  * @param name		the name of @p type, e.g. @c "memory"
3635  * @param type		type type of resource entry to print
3636  * @param format	printf(9) format string to print resource
3637  *			start and end values
3638  *
3639  * @returns		the number of characters printed
3640  */
3641 int
3642 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3643     const char *format)
3644 {
3645 	struct resource_list_entry *rle;
3646 	int printed, retval;
3647 
3648 	printed = 0;
3649 	retval = 0;
3650 	/* Yes, this is kinda cheating */
3651 	STAILQ_FOREACH(rle, rl, link) {
3652 		if (rle->type == type) {
3653 			if (printed == 0)
3654 				retval += printf(" %s ", name);
3655 			else
3656 				retval += printf(",");
3657 			printed++;
3658 			retval += printf(format, rle->start);
3659 			if (rle->count > 1) {
3660 				retval += printf("-");
3661 				retval += printf(format, rle->start +
3662 						 rle->count - 1);
3663 			}
3664 		}
3665 	}
3666 	return (retval);
3667 }
3668 
3669 /**
3670  * @brief Releases all the resources in a list.
3671  *
3672  * @param rl		The resource list to purge.
3673  *
3674  * @returns		nothing
3675  */
3676 void
3677 resource_list_purge(struct resource_list *rl)
3678 {
3679 	struct resource_list_entry *rle;
3680 
3681 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3682 		if (rle->res)
3683 			bus_release_resource(rman_get_device(rle->res),
3684 			    rle->type, rle->rid, rle->res);
3685 		STAILQ_REMOVE_HEAD(rl, link);
3686 		free(rle, M_BUS);
3687 	}
3688 }
3689 
3690 device_t
3691 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3692 {
3693 	return (device_add_child_ordered(dev, order, name, unit));
3694 }
3695 
3696 /**
3697  * @brief Helper function for implementing DEVICE_PROBE()
3698  *
3699  * This function can be used to help implement the DEVICE_PROBE() for
3700  * a bus (i.e. a device which has other devices attached to it). It
3701  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3702  * devclass.
3703  */
3704 int
3705 bus_generic_probe(device_t dev)
3706 {
3707 	devclass_t dc = dev->devclass;
3708 	driverlink_t dl;
3709 
3710 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3711 		/*
3712 		 * If this driver's pass is too high, then ignore it.
3713 		 * For most drivers in the default pass, this will
3714 		 * never be true.  For early-pass drivers they will
3715 		 * only call the identify routines of eligible drivers
3716 		 * when this routine is called.  Drivers for later
3717 		 * passes should have their identify routines called
3718 		 * on early-pass buses during BUS_NEW_PASS().
3719 		 */
3720 		if (dl->pass > bus_current_pass)
3721 			continue;
3722 		DEVICE_IDENTIFY(dl->driver, dev);
3723 	}
3724 
3725 	return (0);
3726 }
3727 
3728 /**
3729  * @brief Helper function for implementing DEVICE_ATTACH()
3730  *
3731  * This function can be used to help implement the DEVICE_ATTACH() for
3732  * a bus. It calls device_probe_and_attach() for each of the device's
3733  * children.
3734  */
3735 int
3736 bus_generic_attach(device_t dev)
3737 {
3738 	device_t child;
3739 
3740 	TAILQ_FOREACH(child, &dev->children, link) {
3741 		device_probe_and_attach(child);
3742 	}
3743 
3744 	return (0);
3745 }
3746 
3747 /**
3748  * @brief Helper function for delaying attaching children
3749  *
3750  * Many buses can't run transactions on the bus which children need to probe and
3751  * attach until after interrupts and/or timers are running.  This function
3752  * delays their attach until interrupts and timers are enabled.
3753  */
3754 int
3755 bus_delayed_attach_children(device_t dev)
3756 {
3757 	/* Probe and attach the bus children when interrupts are available */
3758 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3759 
3760 	return (0);
3761 }
3762 
3763 /**
3764  * @brief Helper function for implementing DEVICE_DETACH()
3765  *
3766  * This function can be used to help implement the DEVICE_DETACH() for
3767  * a bus. It calls device_detach() for each of the device's
3768  * children.
3769  */
3770 int
3771 bus_generic_detach(device_t dev)
3772 {
3773 	device_t child;
3774 	int error;
3775 
3776 	if (dev->state != DS_ATTACHED)
3777 		return (EBUSY);
3778 
3779 	/*
3780 	 * Detach children in the reverse order.
3781 	 * See bus_generic_suspend for details.
3782 	 */
3783 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3784 		if ((error = device_detach(child)) != 0)
3785 			return (error);
3786 	}
3787 
3788 	return (0);
3789 }
3790 
3791 /**
3792  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3793  *
3794  * This function can be used to help implement the DEVICE_SHUTDOWN()
3795  * for a bus. It calls device_shutdown() for each of the device's
3796  * children.
3797  */
3798 int
3799 bus_generic_shutdown(device_t dev)
3800 {
3801 	device_t child;
3802 
3803 	/*
3804 	 * Shut down children in the reverse order.
3805 	 * See bus_generic_suspend for details.
3806 	 */
3807 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3808 		device_shutdown(child);
3809 	}
3810 
3811 	return (0);
3812 }
3813 
3814 /**
3815  * @brief Default function for suspending a child device.
3816  *
3817  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3818  */
3819 int
3820 bus_generic_suspend_child(device_t dev, device_t child)
3821 {
3822 	int	error;
3823 
3824 	error = DEVICE_SUSPEND(child);
3825 
3826 	if (error == 0)
3827 		child->flags |= DF_SUSPENDED;
3828 
3829 	return (error);
3830 }
3831 
3832 /**
3833  * @brief Default function for resuming a child device.
3834  *
3835  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3836  */
3837 int
3838 bus_generic_resume_child(device_t dev, device_t child)
3839 {
3840 	DEVICE_RESUME(child);
3841 	child->flags &= ~DF_SUSPENDED;
3842 
3843 	return (0);
3844 }
3845 
3846 /**
3847  * @brief Helper function for implementing DEVICE_SUSPEND()
3848  *
3849  * This function can be used to help implement the DEVICE_SUSPEND()
3850  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3851  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3852  * operation is aborted and any devices which were suspended are
3853  * resumed immediately by calling their DEVICE_RESUME() methods.
3854  */
3855 int
3856 bus_generic_suspend(device_t dev)
3857 {
3858 	int		error;
3859 	device_t	child;
3860 
3861 	/*
3862 	 * Suspend children in the reverse order.
3863 	 * For most buses all children are equal, so the order does not matter.
3864 	 * Other buses, such as acpi, carefully order their child devices to
3865 	 * express implicit dependencies between them.  For such buses it is
3866 	 * safer to bring down devices in the reverse order.
3867 	 */
3868 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3869 		error = BUS_SUSPEND_CHILD(dev, child);
3870 		if (error != 0) {
3871 			child = TAILQ_NEXT(child, link);
3872 			if (child != NULL) {
3873 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3874 					BUS_RESUME_CHILD(dev, child);
3875 			}
3876 			return (error);
3877 		}
3878 	}
3879 	return (0);
3880 }
3881 
3882 /**
3883  * @brief Helper function for implementing DEVICE_RESUME()
3884  *
3885  * This function can be used to help implement the DEVICE_RESUME() for
3886  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3887  */
3888 int
3889 bus_generic_resume(device_t dev)
3890 {
3891 	device_t	child;
3892 
3893 	TAILQ_FOREACH(child, &dev->children, link) {
3894 		BUS_RESUME_CHILD(dev, child);
3895 		/* if resume fails, there's nothing we can usefully do... */
3896 	}
3897 	return (0);
3898 }
3899 
3900 /**
3901  * @brief Helper function for implementing BUS_RESET_POST
3902  *
3903  * Bus can use this function to implement common operations of
3904  * re-attaching or resuming the children after the bus itself was
3905  * reset, and after restoring bus-unique state of children.
3906  *
3907  * @param dev	The bus
3908  * #param flags	DEVF_RESET_*
3909  */
3910 int
3911 bus_helper_reset_post(device_t dev, int flags)
3912 {
3913 	device_t child;
3914 	int error, error1;
3915 
3916 	error = 0;
3917 	TAILQ_FOREACH(child, &dev->children,link) {
3918 		BUS_RESET_POST(dev, child);
3919 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3920 		    device_probe_and_attach(child) :
3921 		    BUS_RESUME_CHILD(dev, child);
3922 		if (error == 0 && error1 != 0)
3923 			error = error1;
3924 	}
3925 	return (error);
3926 }
3927 
3928 static void
3929 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3930 {
3931 	child = TAILQ_NEXT(child, link);
3932 	if (child == NULL)
3933 		return;
3934 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3935 		BUS_RESET_POST(dev, child);
3936 		if ((flags & DEVF_RESET_DETACH) != 0)
3937 			device_probe_and_attach(child);
3938 		else
3939 			BUS_RESUME_CHILD(dev, child);
3940 	}
3941 }
3942 
3943 /**
3944  * @brief Helper function for implementing BUS_RESET_PREPARE
3945  *
3946  * Bus can use this function to implement common operations of
3947  * detaching or suspending the children before the bus itself is
3948  * reset, and then save bus-unique state of children that must
3949  * persists around reset.
3950  *
3951  * @param dev	The bus
3952  * #param flags	DEVF_RESET_*
3953  */
3954 int
3955 bus_helper_reset_prepare(device_t dev, int flags)
3956 {
3957 	device_t child;
3958 	int error;
3959 
3960 	if (dev->state != DS_ATTACHED)
3961 		return (EBUSY);
3962 
3963 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3964 		if ((flags & DEVF_RESET_DETACH) != 0) {
3965 			error = device_get_state(child) == DS_ATTACHED ?
3966 			    device_detach(child) : 0;
3967 		} else {
3968 			error = BUS_SUSPEND_CHILD(dev, child);
3969 		}
3970 		if (error == 0) {
3971 			error = BUS_RESET_PREPARE(dev, child);
3972 			if (error != 0) {
3973 				if ((flags & DEVF_RESET_DETACH) != 0)
3974 					device_probe_and_attach(child);
3975 				else
3976 					BUS_RESUME_CHILD(dev, child);
3977 			}
3978 		}
3979 		if (error != 0) {
3980 			bus_helper_reset_prepare_rollback(dev, child, flags);
3981 			return (error);
3982 		}
3983 	}
3984 	return (0);
3985 }
3986 
3987 /**
3988  * @brief Helper function for implementing BUS_PRINT_CHILD().
3989  *
3990  * This function prints the first part of the ascii representation of
3991  * @p child, including its name, unit and description (if any - see
3992  * device_set_desc()).
3993  *
3994  * @returns the number of characters printed
3995  */
3996 int
3997 bus_print_child_header(device_t dev, device_t child)
3998 {
3999 	int	retval = 0;
4000 
4001 	if (device_get_desc(child)) {
4002 		retval += device_printf(child, "<%s>", device_get_desc(child));
4003 	} else {
4004 		retval += printf("%s", device_get_nameunit(child));
4005 	}
4006 
4007 	return (retval);
4008 }
4009 
4010 /**
4011  * @brief Helper function for implementing BUS_PRINT_CHILD().
4012  *
4013  * This function prints the last part of the ascii representation of
4014  * @p child, which consists of the string @c " on " followed by the
4015  * name and unit of the @p dev.
4016  *
4017  * @returns the number of characters printed
4018  */
4019 int
4020 bus_print_child_footer(device_t dev, device_t child)
4021 {
4022 	return (printf(" on %s\n", device_get_nameunit(dev)));
4023 }
4024 
4025 /**
4026  * @brief Helper function for implementing BUS_PRINT_CHILD().
4027  *
4028  * This function prints out the VM domain for the given device.
4029  *
4030  * @returns the number of characters printed
4031  */
4032 int
4033 bus_print_child_domain(device_t dev, device_t child)
4034 {
4035 	int domain;
4036 
4037 	/* No domain? Don't print anything */
4038 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4039 		return (0);
4040 
4041 	return (printf(" numa-domain %d", domain));
4042 }
4043 
4044 /**
4045  * @brief Helper function for implementing BUS_PRINT_CHILD().
4046  *
4047  * This function simply calls bus_print_child_header() followed by
4048  * bus_print_child_footer().
4049  *
4050  * @returns the number of characters printed
4051  */
4052 int
4053 bus_generic_print_child(device_t dev, device_t child)
4054 {
4055 	int	retval = 0;
4056 
4057 	retval += bus_print_child_header(dev, child);
4058 	retval += bus_print_child_domain(dev, child);
4059 	retval += bus_print_child_footer(dev, child);
4060 
4061 	return (retval);
4062 }
4063 
4064 /**
4065  * @brief Stub function for implementing BUS_READ_IVAR().
4066  *
4067  * @returns ENOENT
4068  */
4069 int
4070 bus_generic_read_ivar(device_t dev, device_t child, int index,
4071     uintptr_t * result)
4072 {
4073 	return (ENOENT);
4074 }
4075 
4076 /**
4077  * @brief Stub function for implementing BUS_WRITE_IVAR().
4078  *
4079  * @returns ENOENT
4080  */
4081 int
4082 bus_generic_write_ivar(device_t dev, device_t child, int index,
4083     uintptr_t value)
4084 {
4085 	return (ENOENT);
4086 }
4087 
4088 /**
4089  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4090  *
4091  * @returns NULL
4092  */
4093 struct resource_list *
4094 bus_generic_get_resource_list(device_t dev, device_t child)
4095 {
4096 	return (NULL);
4097 }
4098 
4099 /**
4100  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4101  *
4102  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4103  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4104  * and then calls device_probe_and_attach() for each unattached child.
4105  */
4106 void
4107 bus_generic_driver_added(device_t dev, driver_t *driver)
4108 {
4109 	device_t child;
4110 
4111 	DEVICE_IDENTIFY(driver, dev);
4112 	TAILQ_FOREACH(child, &dev->children, link) {
4113 		if (child->state == DS_NOTPRESENT ||
4114 		    (child->flags & DF_REBID))
4115 			device_probe_and_attach(child);
4116 	}
4117 }
4118 
4119 /**
4120  * @brief Helper function for implementing BUS_NEW_PASS().
4121  *
4122  * This implementing of BUS_NEW_PASS() first calls the identify
4123  * routines for any drivers that probe at the current pass.  Then it
4124  * walks the list of devices for this bus.  If a device is already
4125  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4126  * device is not already attached, it attempts to attach a driver to
4127  * it.
4128  */
4129 void
4130 bus_generic_new_pass(device_t dev)
4131 {
4132 	driverlink_t dl;
4133 	devclass_t dc;
4134 	device_t child;
4135 
4136 	dc = dev->devclass;
4137 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4138 		if (dl->pass == bus_current_pass)
4139 			DEVICE_IDENTIFY(dl->driver, dev);
4140 	}
4141 	TAILQ_FOREACH(child, &dev->children, link) {
4142 		if (child->state >= DS_ATTACHED)
4143 			BUS_NEW_PASS(child);
4144 		else if (child->state == DS_NOTPRESENT)
4145 			device_probe_and_attach(child);
4146 	}
4147 }
4148 
4149 /**
4150  * @brief Helper function for implementing BUS_SETUP_INTR().
4151  *
4152  * This simple implementation of BUS_SETUP_INTR() simply calls the
4153  * BUS_SETUP_INTR() method of the parent of @p dev.
4154  */
4155 int
4156 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4157     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4158     void **cookiep)
4159 {
4160 	/* Propagate up the bus hierarchy until someone handles it. */
4161 	if (dev->parent)
4162 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4163 		    filter, intr, arg, cookiep));
4164 	return (EINVAL);
4165 }
4166 
4167 /**
4168  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4169  *
4170  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4171  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4172  */
4173 int
4174 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4175     void *cookie)
4176 {
4177 	/* Propagate up the bus hierarchy until someone handles it. */
4178 	if (dev->parent)
4179 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4180 	return (EINVAL);
4181 }
4182 
4183 /**
4184  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4185  *
4186  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4187  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4188  */
4189 int
4190 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4191 {
4192 	/* Propagate up the bus hierarchy until someone handles it. */
4193 	if (dev->parent)
4194 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4195 	return (EINVAL);
4196 }
4197 
4198 /**
4199  * @brief Helper function for implementing BUS_RESUME_INTR().
4200  *
4201  * This simple implementation of BUS_RESUME_INTR() simply calls the
4202  * BUS_RESUME_INTR() method of the parent of @p dev.
4203  */
4204 int
4205 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4206 {
4207 	/* Propagate up the bus hierarchy until someone handles it. */
4208 	if (dev->parent)
4209 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4210 	return (EINVAL);
4211 }
4212 
4213 /**
4214  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4215  *
4216  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4217  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4218  */
4219 int
4220 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4221     struct resource *r, rman_res_t start, rman_res_t end)
4222 {
4223 	/* Propagate up the bus hierarchy until someone handles it. */
4224 	if (dev->parent)
4225 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4226 		    end));
4227 	return (EINVAL);
4228 }
4229 
4230 /**
4231  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4232  *
4233  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4234  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4235  */
4236 struct resource *
4237 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4238     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4239 {
4240 	/* Propagate up the bus hierarchy until someone handles it. */
4241 	if (dev->parent)
4242 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4243 		    start, end, count, flags));
4244 	return (NULL);
4245 }
4246 
4247 /**
4248  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4249  *
4250  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4251  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4252  */
4253 int
4254 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4255     struct resource *r)
4256 {
4257 	/* Propagate up the bus hierarchy until someone handles it. */
4258 	if (dev->parent)
4259 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4260 		    r));
4261 	return (EINVAL);
4262 }
4263 
4264 /**
4265  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4266  *
4267  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4268  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4269  */
4270 int
4271 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4272     struct resource *r)
4273 {
4274 	/* Propagate up the bus hierarchy until someone handles it. */
4275 	if (dev->parent)
4276 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4277 		    r));
4278 	return (EINVAL);
4279 }
4280 
4281 /**
4282  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4283  *
4284  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4285  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4286  */
4287 int
4288 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4289     int rid, struct resource *r)
4290 {
4291 	/* Propagate up the bus hierarchy until someone handles it. */
4292 	if (dev->parent)
4293 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4294 		    r));
4295 	return (EINVAL);
4296 }
4297 
4298 /**
4299  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4300  *
4301  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4302  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4303  */
4304 int
4305 bus_generic_map_resource(device_t dev, device_t child, int type,
4306     struct resource *r, struct resource_map_request *args,
4307     struct resource_map *map)
4308 {
4309 	/* Propagate up the bus hierarchy until someone handles it. */
4310 	if (dev->parent)
4311 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4312 		    map));
4313 	return (EINVAL);
4314 }
4315 
4316 /**
4317  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4318  *
4319  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4320  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4321  */
4322 int
4323 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4324     struct resource *r, struct resource_map *map)
4325 {
4326 	/* Propagate up the bus hierarchy until someone handles it. */
4327 	if (dev->parent)
4328 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4329 	return (EINVAL);
4330 }
4331 
4332 /**
4333  * @brief Helper function for implementing BUS_BIND_INTR().
4334  *
4335  * This simple implementation of BUS_BIND_INTR() simply calls the
4336  * BUS_BIND_INTR() method of the parent of @p dev.
4337  */
4338 int
4339 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4340     int cpu)
4341 {
4342 	/* Propagate up the bus hierarchy until someone handles it. */
4343 	if (dev->parent)
4344 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4345 	return (EINVAL);
4346 }
4347 
4348 /**
4349  * @brief Helper function for implementing BUS_CONFIG_INTR().
4350  *
4351  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4352  * BUS_CONFIG_INTR() method of the parent of @p dev.
4353  */
4354 int
4355 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4356     enum intr_polarity pol)
4357 {
4358 	/* Propagate up the bus hierarchy until someone handles it. */
4359 	if (dev->parent)
4360 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4361 	return (EINVAL);
4362 }
4363 
4364 /**
4365  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4366  *
4367  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4368  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4369  */
4370 int
4371 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4372     void *cookie, const char *descr)
4373 {
4374 	/* Propagate up the bus hierarchy until someone handles it. */
4375 	if (dev->parent)
4376 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4377 		    descr));
4378 	return (EINVAL);
4379 }
4380 
4381 /**
4382  * @brief Helper function for implementing BUS_GET_CPUS().
4383  *
4384  * This simple implementation of BUS_GET_CPUS() simply calls the
4385  * BUS_GET_CPUS() method of the parent of @p dev.
4386  */
4387 int
4388 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4389     size_t setsize, cpuset_t *cpuset)
4390 {
4391 	/* Propagate up the bus hierarchy until someone handles it. */
4392 	if (dev->parent != NULL)
4393 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4394 	return (EINVAL);
4395 }
4396 
4397 /**
4398  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4399  *
4400  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4401  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4402  */
4403 bus_dma_tag_t
4404 bus_generic_get_dma_tag(device_t dev, device_t child)
4405 {
4406 	/* Propagate up the bus hierarchy until someone handles it. */
4407 	if (dev->parent != NULL)
4408 		return (BUS_GET_DMA_TAG(dev->parent, child));
4409 	return (NULL);
4410 }
4411 
4412 /**
4413  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4414  *
4415  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4416  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4417  */
4418 bus_space_tag_t
4419 bus_generic_get_bus_tag(device_t dev, device_t child)
4420 {
4421 	/* Propagate up the bus hierarchy until someone handles it. */
4422 	if (dev->parent != NULL)
4423 		return (BUS_GET_BUS_TAG(dev->parent, child));
4424 	return ((bus_space_tag_t)0);
4425 }
4426 
4427 /**
4428  * @brief Helper function for implementing BUS_GET_RESOURCE().
4429  *
4430  * This implementation of BUS_GET_RESOURCE() uses the
4431  * resource_list_find() function to do most of the work. It calls
4432  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4433  * search.
4434  */
4435 int
4436 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4437     rman_res_t *startp, rman_res_t *countp)
4438 {
4439 	struct resource_list *		rl = NULL;
4440 	struct resource_list_entry *	rle = NULL;
4441 
4442 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4443 	if (!rl)
4444 		return (EINVAL);
4445 
4446 	rle = resource_list_find(rl, type, rid);
4447 	if (!rle)
4448 		return (ENOENT);
4449 
4450 	if (startp)
4451 		*startp = rle->start;
4452 	if (countp)
4453 		*countp = rle->count;
4454 
4455 	return (0);
4456 }
4457 
4458 /**
4459  * @brief Helper function for implementing BUS_SET_RESOURCE().
4460  *
4461  * This implementation of BUS_SET_RESOURCE() uses the
4462  * resource_list_add() function to do most of the work. It calls
4463  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4464  * edit.
4465  */
4466 int
4467 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4468     rman_res_t start, rman_res_t count)
4469 {
4470 	struct resource_list *		rl = NULL;
4471 
4472 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4473 	if (!rl)
4474 		return (EINVAL);
4475 
4476 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4477 
4478 	return (0);
4479 }
4480 
4481 /**
4482  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4483  *
4484  * This implementation of BUS_DELETE_RESOURCE() uses the
4485  * resource_list_delete() function to do most of the work. It calls
4486  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4487  * edit.
4488  */
4489 void
4490 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4491 {
4492 	struct resource_list *		rl = NULL;
4493 
4494 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4495 	if (!rl)
4496 		return;
4497 
4498 	resource_list_delete(rl, type, rid);
4499 
4500 	return;
4501 }
4502 
4503 /**
4504  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4505  *
4506  * This implementation of BUS_RELEASE_RESOURCE() uses the
4507  * resource_list_release() function to do most of the work. It calls
4508  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4509  */
4510 int
4511 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4512     int rid, struct resource *r)
4513 {
4514 	struct resource_list *		rl = NULL;
4515 
4516 	if (device_get_parent(child) != dev)
4517 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4518 		    type, rid, r));
4519 
4520 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4521 	if (!rl)
4522 		return (EINVAL);
4523 
4524 	return (resource_list_release(rl, dev, child, type, rid, r));
4525 }
4526 
4527 /**
4528  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4529  *
4530  * This implementation of BUS_ALLOC_RESOURCE() uses the
4531  * resource_list_alloc() function to do most of the work. It calls
4532  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4533  */
4534 struct resource *
4535 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4536     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4537 {
4538 	struct resource_list *		rl = NULL;
4539 
4540 	if (device_get_parent(child) != dev)
4541 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4542 		    type, rid, start, end, count, flags));
4543 
4544 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4545 	if (!rl)
4546 		return (NULL);
4547 
4548 	return (resource_list_alloc(rl, dev, child, type, rid,
4549 	    start, end, count, flags));
4550 }
4551 
4552 /**
4553  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4554  *
4555  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4556  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4557  */
4558 int
4559 bus_generic_child_present(device_t dev, device_t child)
4560 {
4561 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4562 }
4563 
4564 int
4565 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4566 {
4567 	if (dev->parent)
4568 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4569 
4570 	return (ENOENT);
4571 }
4572 
4573 /**
4574  * @brief Helper function for implementing BUS_RESCAN().
4575  *
4576  * This null implementation of BUS_RESCAN() always fails to indicate
4577  * the bus does not support rescanning.
4578  */
4579 int
4580 bus_null_rescan(device_t dev)
4581 {
4582 	return (ENXIO);
4583 }
4584 
4585 /*
4586  * Some convenience functions to make it easier for drivers to use the
4587  * resource-management functions.  All these really do is hide the
4588  * indirection through the parent's method table, making for slightly
4589  * less-wordy code.  In the future, it might make sense for this code
4590  * to maintain some sort of a list of resources allocated by each device.
4591  */
4592 
4593 int
4594 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4595     struct resource **res)
4596 {
4597 	int i;
4598 
4599 	for (i = 0; rs[i].type != -1; i++)
4600 		res[i] = NULL;
4601 	for (i = 0; rs[i].type != -1; i++) {
4602 		res[i] = bus_alloc_resource_any(dev,
4603 		    rs[i].type, &rs[i].rid, rs[i].flags);
4604 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4605 			bus_release_resources(dev, rs, res);
4606 			return (ENXIO);
4607 		}
4608 	}
4609 	return (0);
4610 }
4611 
4612 void
4613 bus_release_resources(device_t dev, const struct resource_spec *rs,
4614     struct resource **res)
4615 {
4616 	int i;
4617 
4618 	for (i = 0; rs[i].type != -1; i++)
4619 		if (res[i] != NULL) {
4620 			bus_release_resource(
4621 			    dev, rs[i].type, rs[i].rid, res[i]);
4622 			res[i] = NULL;
4623 		}
4624 }
4625 
4626 /**
4627  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4628  *
4629  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4630  * parent of @p dev.
4631  */
4632 struct resource *
4633 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4634     rman_res_t end, rman_res_t count, u_int flags)
4635 {
4636 	struct resource *res;
4637 
4638 	if (dev->parent == NULL)
4639 		return (NULL);
4640 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4641 	    count, flags);
4642 	return (res);
4643 }
4644 
4645 /**
4646  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4647  *
4648  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4649  * parent of @p dev.
4650  */
4651 int
4652 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4653     rman_res_t end)
4654 {
4655 	if (dev->parent == NULL)
4656 		return (EINVAL);
4657 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4658 }
4659 
4660 /**
4661  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4662  *
4663  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4664  * parent of @p dev.
4665  */
4666 int
4667 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4668 {
4669 	if (dev->parent == NULL)
4670 		return (EINVAL);
4671 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4672 }
4673 
4674 /**
4675  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4676  *
4677  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4678  * parent of @p dev.
4679  */
4680 int
4681 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4682 {
4683 	if (dev->parent == NULL)
4684 		return (EINVAL);
4685 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4686 }
4687 
4688 /**
4689  * @brief Wrapper function for BUS_MAP_RESOURCE().
4690  *
4691  * This function simply calls the BUS_MAP_RESOURCE() method of the
4692  * parent of @p dev.
4693  */
4694 int
4695 bus_map_resource(device_t dev, int type, struct resource *r,
4696     struct resource_map_request *args, struct resource_map *map)
4697 {
4698 	if (dev->parent == NULL)
4699 		return (EINVAL);
4700 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4701 }
4702 
4703 /**
4704  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4705  *
4706  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4707  * parent of @p dev.
4708  */
4709 int
4710 bus_unmap_resource(device_t dev, int type, struct resource *r,
4711     struct resource_map *map)
4712 {
4713 	if (dev->parent == NULL)
4714 		return (EINVAL);
4715 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4716 }
4717 
4718 /**
4719  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4720  *
4721  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4722  * parent of @p dev.
4723  */
4724 int
4725 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4726 {
4727 	int rv;
4728 
4729 	if (dev->parent == NULL)
4730 		return (EINVAL);
4731 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4732 	return (rv);
4733 }
4734 
4735 /**
4736  * @brief Wrapper function for BUS_SETUP_INTR().
4737  *
4738  * This function simply calls the BUS_SETUP_INTR() method of the
4739  * parent of @p dev.
4740  */
4741 int
4742 bus_setup_intr(device_t dev, struct resource *r, int flags,
4743     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4744 {
4745 	int error;
4746 
4747 	if (dev->parent == NULL)
4748 		return (EINVAL);
4749 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4750 	    arg, cookiep);
4751 	if (error != 0)
4752 		return (error);
4753 	if (handler != NULL && !(flags & INTR_MPSAFE))
4754 		device_printf(dev, "[GIANT-LOCKED]\n");
4755 	return (0);
4756 }
4757 
4758 /**
4759  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4760  *
4761  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4762  * parent of @p dev.
4763  */
4764 int
4765 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4766 {
4767 	if (dev->parent == NULL)
4768 		return (EINVAL);
4769 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4770 }
4771 
4772 /**
4773  * @brief Wrapper function for BUS_SUSPEND_INTR().
4774  *
4775  * This function simply calls the BUS_SUSPEND_INTR() method of the
4776  * parent of @p dev.
4777  */
4778 int
4779 bus_suspend_intr(device_t dev, struct resource *r)
4780 {
4781 	if (dev->parent == NULL)
4782 		return (EINVAL);
4783 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4784 }
4785 
4786 /**
4787  * @brief Wrapper function for BUS_RESUME_INTR().
4788  *
4789  * This function simply calls the BUS_RESUME_INTR() method of the
4790  * parent of @p dev.
4791  */
4792 int
4793 bus_resume_intr(device_t dev, struct resource *r)
4794 {
4795 	if (dev->parent == NULL)
4796 		return (EINVAL);
4797 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4798 }
4799 
4800 /**
4801  * @brief Wrapper function for BUS_BIND_INTR().
4802  *
4803  * This function simply calls the BUS_BIND_INTR() method of the
4804  * parent of @p dev.
4805  */
4806 int
4807 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4808 {
4809 	if (dev->parent == NULL)
4810 		return (EINVAL);
4811 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4812 }
4813 
4814 /**
4815  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4816  *
4817  * This function first formats the requested description into a
4818  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4819  * the parent of @p dev.
4820  */
4821 int
4822 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4823     const char *fmt, ...)
4824 {
4825 	va_list ap;
4826 	char descr[MAXCOMLEN + 1];
4827 
4828 	if (dev->parent == NULL)
4829 		return (EINVAL);
4830 	va_start(ap, fmt);
4831 	vsnprintf(descr, sizeof(descr), fmt, ap);
4832 	va_end(ap);
4833 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4834 }
4835 
4836 /**
4837  * @brief Wrapper function for BUS_SET_RESOURCE().
4838  *
4839  * This function simply calls the BUS_SET_RESOURCE() method of the
4840  * parent of @p dev.
4841  */
4842 int
4843 bus_set_resource(device_t dev, int type, int rid,
4844     rman_res_t start, rman_res_t count)
4845 {
4846 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4847 	    start, count));
4848 }
4849 
4850 /**
4851  * @brief Wrapper function for BUS_GET_RESOURCE().
4852  *
4853  * This function simply calls the BUS_GET_RESOURCE() method of the
4854  * parent of @p dev.
4855  */
4856 int
4857 bus_get_resource(device_t dev, int type, int rid,
4858     rman_res_t *startp, rman_res_t *countp)
4859 {
4860 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4861 	    startp, countp));
4862 }
4863 
4864 /**
4865  * @brief Wrapper function for BUS_GET_RESOURCE().
4866  *
4867  * This function simply calls the BUS_GET_RESOURCE() method of the
4868  * parent of @p dev and returns the start value.
4869  */
4870 rman_res_t
4871 bus_get_resource_start(device_t dev, int type, int rid)
4872 {
4873 	rman_res_t start;
4874 	rman_res_t count;
4875 	int error;
4876 
4877 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4878 	    &start, &count);
4879 	if (error)
4880 		return (0);
4881 	return (start);
4882 }
4883 
4884 /**
4885  * @brief Wrapper function for BUS_GET_RESOURCE().
4886  *
4887  * This function simply calls the BUS_GET_RESOURCE() method of the
4888  * parent of @p dev and returns the count value.
4889  */
4890 rman_res_t
4891 bus_get_resource_count(device_t dev, int type, int rid)
4892 {
4893 	rman_res_t start;
4894 	rman_res_t count;
4895 	int error;
4896 
4897 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4898 	    &start, &count);
4899 	if (error)
4900 		return (0);
4901 	return (count);
4902 }
4903 
4904 /**
4905  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4906  *
4907  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4908  * parent of @p dev.
4909  */
4910 void
4911 bus_delete_resource(device_t dev, int type, int rid)
4912 {
4913 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4914 }
4915 
4916 /**
4917  * @brief Wrapper function for BUS_CHILD_PRESENT().
4918  *
4919  * This function simply calls the BUS_CHILD_PRESENT() method of the
4920  * parent of @p dev.
4921  */
4922 int
4923 bus_child_present(device_t child)
4924 {
4925 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4926 }
4927 
4928 /**
4929  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4930  *
4931  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4932  * parent of @p dev.
4933  */
4934 int
4935 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4936 {
4937 	device_t parent;
4938 
4939 	parent = device_get_parent(child);
4940 	if (parent == NULL) {
4941 		*buf = '\0';
4942 		return (0);
4943 	}
4944 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4945 }
4946 
4947 /**
4948  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4949  *
4950  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4951  * parent of @p dev.
4952  */
4953 int
4954 bus_child_location_str(device_t child, char *buf, size_t buflen)
4955 {
4956 	device_t parent;
4957 
4958 	parent = device_get_parent(child);
4959 	if (parent == NULL) {
4960 		*buf = '\0';
4961 		return (0);
4962 	}
4963 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4964 }
4965 
4966 /**
4967  * @brief Wrapper function for BUS_GET_CPUS().
4968  *
4969  * This function simply calls the BUS_GET_CPUS() method of the
4970  * parent of @p dev.
4971  */
4972 int
4973 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
4974 {
4975 	device_t parent;
4976 
4977 	parent = device_get_parent(dev);
4978 	if (parent == NULL)
4979 		return (EINVAL);
4980 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
4981 }
4982 
4983 /**
4984  * @brief Wrapper function for BUS_GET_DMA_TAG().
4985  *
4986  * This function simply calls the BUS_GET_DMA_TAG() method of the
4987  * parent of @p dev.
4988  */
4989 bus_dma_tag_t
4990 bus_get_dma_tag(device_t dev)
4991 {
4992 	device_t parent;
4993 
4994 	parent = device_get_parent(dev);
4995 	if (parent == NULL)
4996 		return (NULL);
4997 	return (BUS_GET_DMA_TAG(parent, dev));
4998 }
4999 
5000 /**
5001  * @brief Wrapper function for BUS_GET_BUS_TAG().
5002  *
5003  * This function simply calls the BUS_GET_BUS_TAG() method of the
5004  * parent of @p dev.
5005  */
5006 bus_space_tag_t
5007 bus_get_bus_tag(device_t dev)
5008 {
5009 	device_t parent;
5010 
5011 	parent = device_get_parent(dev);
5012 	if (parent == NULL)
5013 		return ((bus_space_tag_t)0);
5014 	return (BUS_GET_BUS_TAG(parent, dev));
5015 }
5016 
5017 /**
5018  * @brief Wrapper function for BUS_GET_DOMAIN().
5019  *
5020  * This function simply calls the BUS_GET_DOMAIN() method of the
5021  * parent of @p dev.
5022  */
5023 int
5024 bus_get_domain(device_t dev, int *domain)
5025 {
5026 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5027 }
5028 
5029 /* Resume all devices and then notify userland that we're up again. */
5030 static int
5031 root_resume(device_t dev)
5032 {
5033 	int error;
5034 
5035 	error = bus_generic_resume(dev);
5036 	if (error == 0)
5037 		devctl_notify("kern", "power", "resume", NULL);
5038 	return (error);
5039 }
5040 
5041 static int
5042 root_print_child(device_t dev, device_t child)
5043 {
5044 	int	retval = 0;
5045 
5046 	retval += bus_print_child_header(dev, child);
5047 	retval += printf("\n");
5048 
5049 	return (retval);
5050 }
5051 
5052 static int
5053 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5054     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5055 {
5056 	/*
5057 	 * If an interrupt mapping gets to here something bad has happened.
5058 	 */
5059 	panic("root_setup_intr");
5060 }
5061 
5062 /*
5063  * If we get here, assume that the device is permanent and really is
5064  * present in the system.  Removable bus drivers are expected to intercept
5065  * this call long before it gets here.  We return -1 so that drivers that
5066  * really care can check vs -1 or some ERRNO returned higher in the food
5067  * chain.
5068  */
5069 static int
5070 root_child_present(device_t dev, device_t child)
5071 {
5072 	return (-1);
5073 }
5074 
5075 static int
5076 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5077     cpuset_t *cpuset)
5078 {
5079 	switch (op) {
5080 	case INTR_CPUS:
5081 		/* Default to returning the set of all CPUs. */
5082 		if (setsize != sizeof(cpuset_t))
5083 			return (EINVAL);
5084 		*cpuset = all_cpus;
5085 		return (0);
5086 	default:
5087 		return (EINVAL);
5088 	}
5089 }
5090 
5091 static kobj_method_t root_methods[] = {
5092 	/* Device interface */
5093 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5094 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5095 	KOBJMETHOD(device_resume,	root_resume),
5096 
5097 	/* Bus interface */
5098 	KOBJMETHOD(bus_print_child,	root_print_child),
5099 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5100 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5101 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5102 	KOBJMETHOD(bus_child_present,	root_child_present),
5103 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5104 
5105 	KOBJMETHOD_END
5106 };
5107 
5108 static driver_t root_driver = {
5109 	"root",
5110 	root_methods,
5111 	1,			/* no softc */
5112 };
5113 
5114 device_t	root_bus;
5115 devclass_t	root_devclass;
5116 
5117 static int
5118 root_bus_module_handler(module_t mod, int what, void* arg)
5119 {
5120 	switch (what) {
5121 	case MOD_LOAD:
5122 		TAILQ_INIT(&bus_data_devices);
5123 		kobj_class_compile((kobj_class_t) &root_driver);
5124 		root_bus = make_device(NULL, "root", 0);
5125 		root_bus->desc = "System root bus";
5126 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5127 		root_bus->driver = &root_driver;
5128 		root_bus->state = DS_ATTACHED;
5129 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5130 		devinit();
5131 		return (0);
5132 
5133 	case MOD_SHUTDOWN:
5134 		device_shutdown(root_bus);
5135 		return (0);
5136 	default:
5137 		return (EOPNOTSUPP);
5138 	}
5139 
5140 	return (0);
5141 }
5142 
5143 static moduledata_t root_bus_mod = {
5144 	"rootbus",
5145 	root_bus_module_handler,
5146 	NULL
5147 };
5148 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5149 
5150 /**
5151  * @brief Automatically configure devices
5152  *
5153  * This function begins the autoconfiguration process by calling
5154  * device_probe_and_attach() for each child of the @c root0 device.
5155  */
5156 void
5157 root_bus_configure(void)
5158 {
5159 	PDEBUG(("."));
5160 
5161 	/* Eventually this will be split up, but this is sufficient for now. */
5162 	bus_set_pass(BUS_PASS_DEFAULT);
5163 }
5164 
5165 /**
5166  * @brief Module handler for registering device drivers
5167  *
5168  * This module handler is used to automatically register device
5169  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5170  * devclass_add_driver() for the driver described by the
5171  * driver_module_data structure pointed to by @p arg
5172  */
5173 int
5174 driver_module_handler(module_t mod, int what, void *arg)
5175 {
5176 	struct driver_module_data *dmd;
5177 	devclass_t bus_devclass;
5178 	kobj_class_t driver;
5179 	int error, pass;
5180 
5181 	dmd = (struct driver_module_data *)arg;
5182 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5183 	error = 0;
5184 
5185 	switch (what) {
5186 	case MOD_LOAD:
5187 		if (dmd->dmd_chainevh)
5188 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5189 
5190 		pass = dmd->dmd_pass;
5191 		driver = dmd->dmd_driver;
5192 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5193 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5194 		error = devclass_add_driver(bus_devclass, driver, pass,
5195 		    dmd->dmd_devclass);
5196 		break;
5197 
5198 	case MOD_UNLOAD:
5199 		PDEBUG(("Unloading module: driver %s from bus %s",
5200 		    DRIVERNAME(dmd->dmd_driver),
5201 		    dmd->dmd_busname));
5202 		error = devclass_delete_driver(bus_devclass,
5203 		    dmd->dmd_driver);
5204 
5205 		if (!error && dmd->dmd_chainevh)
5206 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5207 		break;
5208 	case MOD_QUIESCE:
5209 		PDEBUG(("Quiesce module: driver %s from bus %s",
5210 		    DRIVERNAME(dmd->dmd_driver),
5211 		    dmd->dmd_busname));
5212 		error = devclass_quiesce_driver(bus_devclass,
5213 		    dmd->dmd_driver);
5214 
5215 		if (!error && dmd->dmd_chainevh)
5216 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5217 		break;
5218 	default:
5219 		error = EOPNOTSUPP;
5220 		break;
5221 	}
5222 
5223 	return (error);
5224 }
5225 
5226 /**
5227  * @brief Enumerate all hinted devices for this bus.
5228  *
5229  * Walks through the hints for this bus and calls the bus_hinted_child
5230  * routine for each one it fines.  It searches first for the specific
5231  * bus that's being probed for hinted children (eg isa0), and then for
5232  * generic children (eg isa).
5233  *
5234  * @param	dev	bus device to enumerate
5235  */
5236 void
5237 bus_enumerate_hinted_children(device_t bus)
5238 {
5239 	int i;
5240 	const char *dname, *busname;
5241 	int dunit;
5242 
5243 	/*
5244 	 * enumerate all devices on the specific bus
5245 	 */
5246 	busname = device_get_nameunit(bus);
5247 	i = 0;
5248 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5249 		BUS_HINTED_CHILD(bus, dname, dunit);
5250 
5251 	/*
5252 	 * and all the generic ones.
5253 	 */
5254 	busname = device_get_name(bus);
5255 	i = 0;
5256 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5257 		BUS_HINTED_CHILD(bus, dname, dunit);
5258 }
5259 
5260 #ifdef BUS_DEBUG
5261 
5262 /* the _short versions avoid iteration by not calling anything that prints
5263  * more than oneliners. I love oneliners.
5264  */
5265 
5266 static void
5267 print_device_short(device_t dev, int indent)
5268 {
5269 	if (!dev)
5270 		return;
5271 
5272 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5273 	    dev->unit, dev->desc,
5274 	    (dev->parent? "":"no "),
5275 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5276 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5277 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5278 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5279 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5280 	    (dev->flags&DF_REBID? "rebiddable,":""),
5281 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5282 	    (dev->ivars? "":"no "),
5283 	    (dev->softc? "":"no "),
5284 	    dev->busy));
5285 }
5286 
5287 static void
5288 print_device(device_t dev, int indent)
5289 {
5290 	if (!dev)
5291 		return;
5292 
5293 	print_device_short(dev, indent);
5294 
5295 	indentprintf(("Parent:\n"));
5296 	print_device_short(dev->parent, indent+1);
5297 	indentprintf(("Driver:\n"));
5298 	print_driver_short(dev->driver, indent+1);
5299 	indentprintf(("Devclass:\n"));
5300 	print_devclass_short(dev->devclass, indent+1);
5301 }
5302 
5303 void
5304 print_device_tree_short(device_t dev, int indent)
5305 /* print the device and all its children (indented) */
5306 {
5307 	device_t child;
5308 
5309 	if (!dev)
5310 		return;
5311 
5312 	print_device_short(dev, indent);
5313 
5314 	TAILQ_FOREACH(child, &dev->children, link) {
5315 		print_device_tree_short(child, indent+1);
5316 	}
5317 }
5318 
5319 void
5320 print_device_tree(device_t dev, int indent)
5321 /* print the device and all its children (indented) */
5322 {
5323 	device_t child;
5324 
5325 	if (!dev)
5326 		return;
5327 
5328 	print_device(dev, indent);
5329 
5330 	TAILQ_FOREACH(child, &dev->children, link) {
5331 		print_device_tree(child, indent+1);
5332 	}
5333 }
5334 
5335 static void
5336 print_driver_short(driver_t *driver, int indent)
5337 {
5338 	if (!driver)
5339 		return;
5340 
5341 	indentprintf(("driver %s: softc size = %zd\n",
5342 	    driver->name, driver->size));
5343 }
5344 
5345 static void
5346 print_driver(driver_t *driver, int indent)
5347 {
5348 	if (!driver)
5349 		return;
5350 
5351 	print_driver_short(driver, indent);
5352 }
5353 
5354 static void
5355 print_driver_list(driver_list_t drivers, int indent)
5356 {
5357 	driverlink_t driver;
5358 
5359 	TAILQ_FOREACH(driver, &drivers, link) {
5360 		print_driver(driver->driver, indent);
5361 	}
5362 }
5363 
5364 static void
5365 print_devclass_short(devclass_t dc, int indent)
5366 {
5367 	if ( !dc )
5368 		return;
5369 
5370 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5371 }
5372 
5373 static void
5374 print_devclass(devclass_t dc, int indent)
5375 {
5376 	int i;
5377 
5378 	if ( !dc )
5379 		return;
5380 
5381 	print_devclass_short(dc, indent);
5382 	indentprintf(("Drivers:\n"));
5383 	print_driver_list(dc->drivers, indent+1);
5384 
5385 	indentprintf(("Devices:\n"));
5386 	for (i = 0; i < dc->maxunit; i++)
5387 		if (dc->devices[i])
5388 			print_device(dc->devices[i], indent+1);
5389 }
5390 
5391 void
5392 print_devclass_list_short(void)
5393 {
5394 	devclass_t dc;
5395 
5396 	printf("Short listing of devclasses, drivers & devices:\n");
5397 	TAILQ_FOREACH(dc, &devclasses, link) {
5398 		print_devclass_short(dc, 0);
5399 	}
5400 }
5401 
5402 void
5403 print_devclass_list(void)
5404 {
5405 	devclass_t dc;
5406 
5407 	printf("Full listing of devclasses, drivers & devices:\n");
5408 	TAILQ_FOREACH(dc, &devclasses, link) {
5409 		print_devclass(dc, 0);
5410 	}
5411 }
5412 
5413 #endif
5414 
5415 /*
5416  * User-space access to the device tree.
5417  *
5418  * We implement a small set of nodes:
5419  *
5420  * hw.bus			Single integer read method to obtain the
5421  *				current generation count.
5422  * hw.bus.devices		Reads the entire device tree in flat space.
5423  * hw.bus.rman			Resource manager interface
5424  *
5425  * We might like to add the ability to scan devclasses and/or drivers to
5426  * determine what else is currently loaded/available.
5427  */
5428 
5429 static int
5430 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5431 {
5432 	struct u_businfo	ubus;
5433 
5434 	ubus.ub_version = BUS_USER_VERSION;
5435 	ubus.ub_generation = bus_data_generation;
5436 
5437 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5438 }
5439 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5440     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5441     "bus-related data");
5442 
5443 static int
5444 sysctl_devices(SYSCTL_HANDLER_ARGS)
5445 {
5446 	int			*name = (int *)arg1;
5447 	u_int			namelen = arg2;
5448 	int			index;
5449 	device_t		dev;
5450 	struct u_device		*udev;
5451 	int			error;
5452 	char			*walker, *ep;
5453 
5454 	if (namelen != 2)
5455 		return (EINVAL);
5456 
5457 	if (bus_data_generation_check(name[0]))
5458 		return (EINVAL);
5459 
5460 	index = name[1];
5461 
5462 	/*
5463 	 * Scan the list of devices, looking for the requested index.
5464 	 */
5465 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5466 		if (index-- == 0)
5467 			break;
5468 	}
5469 	if (dev == NULL)
5470 		return (ENOENT);
5471 
5472 	/*
5473 	 * Populate the return item, careful not to overflow the buffer.
5474 	 */
5475 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5476 	if (udev == NULL)
5477 		return (ENOMEM);
5478 	udev->dv_handle = (uintptr_t)dev;
5479 	udev->dv_parent = (uintptr_t)dev->parent;
5480 	udev->dv_devflags = dev->devflags;
5481 	udev->dv_flags = dev->flags;
5482 	udev->dv_state = dev->state;
5483 	walker = udev->dv_fields;
5484 	ep = walker + sizeof(udev->dv_fields);
5485 #define CP(src)						\
5486 	if ((src) == NULL)				\
5487 		*walker++ = '\0';			\
5488 	else {						\
5489 		strlcpy(walker, (src), ep - walker);	\
5490 		walker += strlen(walker) + 1;		\
5491 	}						\
5492 	if (walker >= ep)				\
5493 		break;
5494 
5495 	do {
5496 		CP(dev->nameunit);
5497 		CP(dev->desc);
5498 		CP(dev->driver != NULL ? dev->driver->name : NULL);
5499 		bus_child_pnpinfo_str(dev, walker, ep - walker);
5500 		walker += strlen(walker) + 1;
5501 		if (walker >= ep)
5502 			break;
5503 		bus_child_location_str(dev, walker, ep - walker);
5504 		walker += strlen(walker) + 1;
5505 		if (walker >= ep)
5506 			break;
5507 		*walker++ = '\0';
5508 	} while (0);
5509 #undef CP
5510 	error = SYSCTL_OUT(req, udev, sizeof(*udev));
5511 	free(udev, M_BUS);
5512 	return (error);
5513 }
5514 
5515 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5516     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5517     "system device tree");
5518 
5519 int
5520 bus_data_generation_check(int generation)
5521 {
5522 	if (generation != bus_data_generation)
5523 		return (1);
5524 
5525 	/* XXX generate optimised lists here? */
5526 	return (0);
5527 }
5528 
5529 void
5530 bus_data_generation_update(void)
5531 {
5532 	atomic_add_int(&bus_data_generation, 1);
5533 }
5534 
5535 int
5536 bus_free_resource(device_t dev, int type, struct resource *r)
5537 {
5538 	if (r == NULL)
5539 		return (0);
5540 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5541 }
5542 
5543 device_t
5544 device_lookup_by_name(const char *name)
5545 {
5546 	device_t dev;
5547 
5548 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5549 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5550 			return (dev);
5551 	}
5552 	return (NULL);
5553 }
5554 
5555 /*
5556  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5557  * implicit semantics on open, so it could not be reused for this.
5558  * Another option would be to call this /dev/bus?
5559  */
5560 static int
5561 find_device(struct devreq *req, device_t *devp)
5562 {
5563 	device_t dev;
5564 
5565 	/*
5566 	 * First, ensure that the name is nul terminated.
5567 	 */
5568 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5569 		return (EINVAL);
5570 
5571 	/*
5572 	 * Second, try to find an attached device whose name matches
5573 	 * 'name'.
5574 	 */
5575 	dev = device_lookup_by_name(req->dr_name);
5576 	if (dev != NULL) {
5577 		*devp = dev;
5578 		return (0);
5579 	}
5580 
5581 	/* Finally, give device enumerators a chance. */
5582 	dev = NULL;
5583 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5584 	if (dev == NULL)
5585 		return (ENOENT);
5586 	*devp = dev;
5587 	return (0);
5588 }
5589 
5590 static bool
5591 driver_exists(device_t bus, const char *driver)
5592 {
5593 	devclass_t dc;
5594 
5595 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5596 		if (devclass_find_driver_internal(dc, driver) != NULL)
5597 			return (true);
5598 	}
5599 	return (false);
5600 }
5601 
5602 static void
5603 device_gen_nomatch(device_t dev)
5604 {
5605 	device_t child;
5606 
5607 	if (dev->flags & DF_NEEDNOMATCH &&
5608 	    dev->state == DS_NOTPRESENT) {
5609 		BUS_PROBE_NOMATCH(dev->parent, dev);
5610 		devnomatch(dev);
5611 		dev->flags |= DF_DONENOMATCH;
5612 	}
5613 	dev->flags &= ~DF_NEEDNOMATCH;
5614 	TAILQ_FOREACH(child, &dev->children, link) {
5615 		device_gen_nomatch(child);
5616 	}
5617 }
5618 
5619 static void
5620 device_do_deferred_actions(void)
5621 {
5622 	devclass_t dc;
5623 	driverlink_t dl;
5624 
5625 	/*
5626 	 * Walk through the devclasses to find all the drivers we've tagged as
5627 	 * deferred during the freeze and call the driver added routines. They
5628 	 * have already been added to the lists in the background, so the driver
5629 	 * added routines that trigger a probe will have all the right bidders
5630 	 * for the probe auction.
5631 	 */
5632 	TAILQ_FOREACH(dc, &devclasses, link) {
5633 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5634 			if (dl->flags & DL_DEFERRED_PROBE) {
5635 				devclass_driver_added(dc, dl->driver);
5636 				dl->flags &= ~DL_DEFERRED_PROBE;
5637 			}
5638 		}
5639 	}
5640 
5641 	/*
5642 	 * We also defer no-match events during a freeze. Walk the tree and
5643 	 * generate all the pent-up events that are still relevant.
5644 	 */
5645 	device_gen_nomatch(root_bus);
5646 	bus_data_generation_update();
5647 }
5648 
5649 static int
5650 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5651     struct thread *td)
5652 {
5653 	struct devreq *req;
5654 	device_t dev;
5655 	int error, old;
5656 
5657 	/* Locate the device to control. */
5658 	mtx_lock(&Giant);
5659 	req = (struct devreq *)data;
5660 	switch (cmd) {
5661 	case DEV_ATTACH:
5662 	case DEV_DETACH:
5663 	case DEV_ENABLE:
5664 	case DEV_DISABLE:
5665 	case DEV_SUSPEND:
5666 	case DEV_RESUME:
5667 	case DEV_SET_DRIVER:
5668 	case DEV_CLEAR_DRIVER:
5669 	case DEV_RESCAN:
5670 	case DEV_DELETE:
5671 	case DEV_RESET:
5672 		error = priv_check(td, PRIV_DRIVER);
5673 		if (error == 0)
5674 			error = find_device(req, &dev);
5675 		break;
5676 	case DEV_FREEZE:
5677 	case DEV_THAW:
5678 		error = priv_check(td, PRIV_DRIVER);
5679 		break;
5680 	default:
5681 		error = ENOTTY;
5682 		break;
5683 	}
5684 	if (error) {
5685 		mtx_unlock(&Giant);
5686 		return (error);
5687 	}
5688 
5689 	/* Perform the requested operation. */
5690 	switch (cmd) {
5691 	case DEV_ATTACH:
5692 		if (device_is_attached(dev) && (dev->flags & DF_REBID) == 0)
5693 			error = EBUSY;
5694 		else if (!device_is_enabled(dev))
5695 			error = ENXIO;
5696 		else
5697 			error = device_probe_and_attach(dev);
5698 		break;
5699 	case DEV_DETACH:
5700 		if (!device_is_attached(dev)) {
5701 			error = ENXIO;
5702 			break;
5703 		}
5704 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5705 			error = device_quiesce(dev);
5706 			if (error)
5707 				break;
5708 		}
5709 		error = device_detach(dev);
5710 		break;
5711 	case DEV_ENABLE:
5712 		if (device_is_enabled(dev)) {
5713 			error = EBUSY;
5714 			break;
5715 		}
5716 
5717 		/*
5718 		 * If the device has been probed but not attached (e.g.
5719 		 * when it has been disabled by a loader hint), just
5720 		 * attach the device rather than doing a full probe.
5721 		 */
5722 		device_enable(dev);
5723 		if (device_is_alive(dev)) {
5724 			/*
5725 			 * If the device was disabled via a hint, clear
5726 			 * the hint.
5727 			 */
5728 			if (resource_disabled(dev->driver->name, dev->unit))
5729 				resource_unset_value(dev->driver->name,
5730 				    dev->unit, "disabled");
5731 			error = device_attach(dev);
5732 		} else
5733 			error = device_probe_and_attach(dev);
5734 		break;
5735 	case DEV_DISABLE:
5736 		if (!device_is_enabled(dev)) {
5737 			error = ENXIO;
5738 			break;
5739 		}
5740 
5741 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5742 			error = device_quiesce(dev);
5743 			if (error)
5744 				break;
5745 		}
5746 
5747 		/*
5748 		 * Force DF_FIXEDCLASS on around detach to preserve
5749 		 * the existing name.
5750 		 */
5751 		old = dev->flags;
5752 		dev->flags |= DF_FIXEDCLASS;
5753 		error = device_detach(dev);
5754 		if (!(old & DF_FIXEDCLASS))
5755 			dev->flags &= ~DF_FIXEDCLASS;
5756 		if (error == 0)
5757 			device_disable(dev);
5758 		break;
5759 	case DEV_SUSPEND:
5760 		if (device_is_suspended(dev)) {
5761 			error = EBUSY;
5762 			break;
5763 		}
5764 		if (device_get_parent(dev) == NULL) {
5765 			error = EINVAL;
5766 			break;
5767 		}
5768 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5769 		break;
5770 	case DEV_RESUME:
5771 		if (!device_is_suspended(dev)) {
5772 			error = EINVAL;
5773 			break;
5774 		}
5775 		if (device_get_parent(dev) == NULL) {
5776 			error = EINVAL;
5777 			break;
5778 		}
5779 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5780 		break;
5781 	case DEV_SET_DRIVER: {
5782 		devclass_t dc;
5783 		char driver[128];
5784 
5785 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5786 		if (error)
5787 			break;
5788 		if (driver[0] == '\0') {
5789 			error = EINVAL;
5790 			break;
5791 		}
5792 		if (dev->devclass != NULL &&
5793 		    strcmp(driver, dev->devclass->name) == 0)
5794 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5795 			break;
5796 
5797 		/*
5798 		 * Scan drivers for this device's bus looking for at
5799 		 * least one matching driver.
5800 		 */
5801 		if (dev->parent == NULL) {
5802 			error = EINVAL;
5803 			break;
5804 		}
5805 		if (!driver_exists(dev->parent, driver)) {
5806 			error = ENOENT;
5807 			break;
5808 		}
5809 		dc = devclass_create(driver);
5810 		if (dc == NULL) {
5811 			error = ENOMEM;
5812 			break;
5813 		}
5814 
5815 		/* Detach device if necessary. */
5816 		if (device_is_attached(dev)) {
5817 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5818 				error = device_detach(dev);
5819 			else
5820 				error = EBUSY;
5821 			if (error)
5822 				break;
5823 		}
5824 
5825 		/* Clear any previously-fixed device class and unit. */
5826 		if (dev->flags & DF_FIXEDCLASS)
5827 			devclass_delete_device(dev->devclass, dev);
5828 		dev->flags |= DF_WILDCARD;
5829 		dev->unit = -1;
5830 
5831 		/* Force the new device class. */
5832 		error = devclass_add_device(dc, dev);
5833 		if (error)
5834 			break;
5835 		dev->flags |= DF_FIXEDCLASS;
5836 		error = device_probe_and_attach(dev);
5837 		break;
5838 	}
5839 	case DEV_CLEAR_DRIVER:
5840 		if (!(dev->flags & DF_FIXEDCLASS)) {
5841 			error = 0;
5842 			break;
5843 		}
5844 		if (device_is_attached(dev)) {
5845 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5846 				error = device_detach(dev);
5847 			else
5848 				error = EBUSY;
5849 			if (error)
5850 				break;
5851 		}
5852 
5853 		dev->flags &= ~DF_FIXEDCLASS;
5854 		dev->flags |= DF_WILDCARD;
5855 		devclass_delete_device(dev->devclass, dev);
5856 		error = device_probe_and_attach(dev);
5857 		break;
5858 	case DEV_RESCAN:
5859 		if (!device_is_attached(dev)) {
5860 			error = ENXIO;
5861 			break;
5862 		}
5863 		error = BUS_RESCAN(dev);
5864 		break;
5865 	case DEV_DELETE: {
5866 		device_t parent;
5867 
5868 		parent = device_get_parent(dev);
5869 		if (parent == NULL) {
5870 			error = EINVAL;
5871 			break;
5872 		}
5873 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5874 			if (bus_child_present(dev) != 0) {
5875 				error = EBUSY;
5876 				break;
5877 			}
5878 		}
5879 
5880 		error = device_delete_child(parent, dev);
5881 		break;
5882 	}
5883 	case DEV_FREEZE:
5884 		if (device_frozen)
5885 			error = EBUSY;
5886 		else
5887 			device_frozen = true;
5888 		break;
5889 	case DEV_THAW:
5890 		if (!device_frozen)
5891 			error = EBUSY;
5892 		else {
5893 			device_do_deferred_actions();
5894 			device_frozen = false;
5895 		}
5896 		break;
5897 	case DEV_RESET:
5898 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5899 			error = EINVAL;
5900 			break;
5901 		}
5902 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5903 		    req->dr_flags);
5904 		break;
5905 	}
5906 	mtx_unlock(&Giant);
5907 	return (error);
5908 }
5909 
5910 static struct cdevsw devctl2_cdevsw = {
5911 	.d_version =	D_VERSION,
5912 	.d_ioctl =	devctl2_ioctl,
5913 	.d_name =	"devctl2",
5914 };
5915 
5916 static void
5917 devctl2_init(void)
5918 {
5919 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5920 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5921 }
5922 
5923 /*
5924  * APIs to manage deprecation and obsolescence.
5925  */
5926 static int obsolete_panic = 0;
5927 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
5928     "Panic when obsolete features are used (0 = never, 1 = if osbolete, "
5929     "2 = if deprecated)");
5930 
5931 static void
5932 gone_panic(int major, int running, const char *msg)
5933 {
5934 	switch (obsolete_panic)
5935 	{
5936 	case 0:
5937 		return;
5938 	case 1:
5939 		if (running < major)
5940 			return;
5941 		/* FALLTHROUGH */
5942 	default:
5943 		panic("%s", msg);
5944 	}
5945 }
5946 
5947 void
5948 _gone_in(int major, const char *msg)
5949 {
5950 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5951 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5952 		printf("Obsolete code will be removed soon: %s\n", msg);
5953 	else
5954 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
5955 		    major, msg);
5956 }
5957 
5958 void
5959 _gone_in_dev(device_t dev, int major, const char *msg)
5960 {
5961 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5962 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5963 		device_printf(dev,
5964 		    "Obsolete code will be removed soon: %s\n", msg);
5965 	else
5966 		device_printf(dev,
5967 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
5968 		    major, msg);
5969 }
5970 
5971 #ifdef DDB
5972 DB_SHOW_COMMAND(device, db_show_device)
5973 {
5974 	device_t dev;
5975 
5976 	if (!have_addr)
5977 		return;
5978 
5979 	dev = (device_t)addr;
5980 
5981 	db_printf("name:    %s\n", device_get_nameunit(dev));
5982 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
5983 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
5984 	db_printf("  addr:    %p\n", dev);
5985 	db_printf("  parent:  %p\n", dev->parent);
5986 	db_printf("  softc:   %p\n", dev->softc);
5987 	db_printf("  ivars:   %p\n", dev->ivars);
5988 }
5989 
5990 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
5991 {
5992 	device_t dev;
5993 
5994 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5995 		db_show_device((db_expr_t)dev, true, count, modif);
5996 	}
5997 }
5998 #endif
5999