xref: /freebsd/sys/kern/subr_bus.c (revision 1165fc9a526630487a1feb63daef65c5aee1a583)
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/refcount.h>
55 #include <sys/rman.h>
56 #include <sys/sbuf.h>
57 #include <sys/selinfo.h>
58 #include <sys/signalvar.h>
59 #include <sys/smp.h>
60 #include <sys/sysctl.h>
61 #include <sys/systm.h>
62 #include <sys/uio.h>
63 #include <sys/bus.h>
64 #include <sys/cpuset.h>
65 
66 #include <net/vnet.h>
67 
68 #include <machine/cpu.h>
69 #include <machine/stdarg.h>
70 
71 #include <vm/uma.h>
72 #include <vm/vm.h>
73 
74 #include <ddb/ddb.h>
75 
76 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
77     NULL);
78 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
79     NULL);
80 
81 /*
82  * Used to attach drivers to devclasses.
83  */
84 typedef struct driverlink *driverlink_t;
85 struct driverlink {
86 	kobj_class_t	driver;
87 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
88 	int		pass;
89 	int		flags;
90 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
91 	TAILQ_ENTRY(driverlink) passlink;
92 };
93 
94 /*
95  * Forward declarations
96  */
97 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
98 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
99 typedef TAILQ_HEAD(device_list, _device) device_list_t;
100 
101 struct devclass {
102 	TAILQ_ENTRY(devclass) link;
103 	devclass_t	parent;		/* parent in devclass hierarchy */
104 	driver_list_t	drivers;	/* bus devclasses store drivers for bus */
105 	char		*name;
106 	device_t	*devices;	/* array of devices indexed by unit */
107 	int		maxunit;	/* size of devices array */
108 	int		flags;
109 #define DC_HAS_CHILDREN		1
110 
111 	struct sysctl_ctx_list sysctl_ctx;
112 	struct sysctl_oid *sysctl_tree;
113 };
114 
115 /**
116  * @brief Implementation of _device.
117  *
118  * The structure is named "_device" instead of "device" to avoid type confusion
119  * caused by other subsystems defining a (struct device).
120  */
121 struct _device {
122 	/*
123 	 * A device is a kernel object. The first field must be the
124 	 * current ops table for the object.
125 	 */
126 	KOBJ_FIELDS;
127 
128 	/*
129 	 * Device hierarchy.
130 	 */
131 	TAILQ_ENTRY(_device)	link;	/**< list of devices in parent */
132 	TAILQ_ENTRY(_device)	devlink; /**< global device list membership */
133 	device_t	parent;		/**< parent of this device  */
134 	device_list_t	children;	/**< list of child devices */
135 
136 	/*
137 	 * Details of this device.
138 	 */
139 	driver_t	*driver;	/**< current driver */
140 	devclass_t	devclass;	/**< current device class */
141 	int		unit;		/**< current unit number */
142 	char*		nameunit;	/**< name+unit e.g. foodev0 */
143 	char*		desc;		/**< driver specific description */
144 	u_int		busy;		/**< count of calls to device_busy() */
145 	device_state_t	state;		/**< current device state  */
146 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
147 	u_int		flags;		/**< internal device flags  */
148 	u_int	order;			/**< order from device_add_child_ordered() */
149 	void	*ivars;			/**< instance variables  */
150 	void	*softc;			/**< current driver's variables  */
151 
152 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
153 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
154 };
155 
156 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
157 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
158 
159 EVENTHANDLER_LIST_DEFINE(device_attach);
160 EVENTHANDLER_LIST_DEFINE(device_detach);
161 EVENTHANDLER_LIST_DEFINE(dev_lookup);
162 
163 static void devctl2_init(void);
164 static bool device_frozen;
165 
166 #define DRIVERNAME(d)	((d)? d->name : "no driver")
167 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
168 
169 #ifdef BUS_DEBUG
170 
171 static int bus_debug = 1;
172 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
173     "Bus debug level");
174 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
175 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
176 
177 /**
178  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
179  * prevent syslog from deleting initial spaces
180  */
181 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
182 
183 static void print_device_short(device_t dev, int indent);
184 static void print_device(device_t dev, int indent);
185 void print_device_tree_short(device_t dev, int indent);
186 void print_device_tree(device_t dev, int indent);
187 static void print_driver_short(driver_t *driver, int indent);
188 static void print_driver(driver_t *driver, int indent);
189 static void print_driver_list(driver_list_t drivers, int indent);
190 static void print_devclass_short(devclass_t dc, int indent);
191 static void print_devclass(devclass_t dc, int indent);
192 void print_devclass_list_short(void);
193 void print_devclass_list(void);
194 
195 #else
196 /* Make the compiler ignore the function calls */
197 #define PDEBUG(a)			/* nop */
198 #define DEVICENAME(d)			/* nop */
199 
200 #define print_device_short(d,i)		/* nop */
201 #define print_device(d,i)		/* nop */
202 #define print_device_tree_short(d,i)	/* nop */
203 #define print_device_tree(d,i)		/* nop */
204 #define print_driver_short(d,i)		/* nop */
205 #define print_driver(d,i)		/* nop */
206 #define print_driver_list(d,i)		/* nop */
207 #define print_devclass_short(d,i)	/* nop */
208 #define print_devclass(d,i)		/* nop */
209 #define print_devclass_list_short()	/* nop */
210 #define print_devclass_list()		/* nop */
211 #endif
212 
213 /*
214  * dev sysctl tree
215  */
216 
217 enum {
218 	DEVCLASS_SYSCTL_PARENT,
219 };
220 
221 static int
222 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
223 {
224 	devclass_t dc = (devclass_t)arg1;
225 	const char *value;
226 
227 	switch (arg2) {
228 	case DEVCLASS_SYSCTL_PARENT:
229 		value = dc->parent ? dc->parent->name : "";
230 		break;
231 	default:
232 		return (EINVAL);
233 	}
234 	return (SYSCTL_OUT_STR(req, value));
235 }
236 
237 static void
238 devclass_sysctl_init(devclass_t dc)
239 {
240 	if (dc->sysctl_tree != NULL)
241 		return;
242 	sysctl_ctx_init(&dc->sysctl_ctx);
243 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
244 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
245 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
246 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
247 	    OID_AUTO, "%parent",
248 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
249 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
250 	    "parent class");
251 }
252 
253 enum {
254 	DEVICE_SYSCTL_DESC,
255 	DEVICE_SYSCTL_DRIVER,
256 	DEVICE_SYSCTL_LOCATION,
257 	DEVICE_SYSCTL_PNPINFO,
258 	DEVICE_SYSCTL_PARENT,
259 };
260 
261 static int
262 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
263 {
264 	struct sbuf sb;
265 	device_t dev = (device_t)arg1;
266 	int error;
267 
268 	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
269 	sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
270 	bus_topo_lock();
271 	switch (arg2) {
272 	case DEVICE_SYSCTL_DESC:
273 		sbuf_cat(&sb, dev->desc ? dev->desc : "");
274 		break;
275 	case DEVICE_SYSCTL_DRIVER:
276 		sbuf_cat(&sb, dev->driver ? dev->driver->name : "");
277 		break;
278 	case DEVICE_SYSCTL_LOCATION:
279 		bus_child_location(dev, &sb);
280 		break;
281 	case DEVICE_SYSCTL_PNPINFO:
282 		bus_child_pnpinfo(dev, &sb);
283 		break;
284 	case DEVICE_SYSCTL_PARENT:
285 		sbuf_cat(&sb, dev->parent ? dev->parent->nameunit : "");
286 		break;
287 	default:
288 		error = EINVAL;
289 		goto out;
290 	}
291 	error = sbuf_finish(&sb);
292 out:
293 	bus_topo_unlock();
294 	sbuf_delete(&sb);
295 	return (error);
296 }
297 
298 static void
299 device_sysctl_init(device_t dev)
300 {
301 	devclass_t dc = dev->devclass;
302 	int domain;
303 
304 	if (dev->sysctl_tree != NULL)
305 		return;
306 	devclass_sysctl_init(dc);
307 	sysctl_ctx_init(&dev->sysctl_ctx);
308 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
309 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
310 	    dev->nameunit + strlen(dc->name),
311 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
312 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
313 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
314 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
315 	    "device description");
316 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
317 	    OID_AUTO, "%driver",
318 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
319 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
320 	    "device driver name");
321 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
322 	    OID_AUTO, "%location",
323 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
324 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
325 	    "device location relative to parent");
326 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
327 	    OID_AUTO, "%pnpinfo",
328 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
329 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
330 	    "device identification");
331 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
332 	    OID_AUTO, "%parent",
333 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
334 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
335 	    "parent device");
336 	if (bus_get_domain(dev, &domain) == 0)
337 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
338 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
339 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, domain, "NUMA domain");
340 }
341 
342 static void
343 device_sysctl_update(device_t dev)
344 {
345 	devclass_t dc = dev->devclass;
346 
347 	if (dev->sysctl_tree == NULL)
348 		return;
349 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
350 }
351 
352 static void
353 device_sysctl_fini(device_t dev)
354 {
355 	if (dev->sysctl_tree == NULL)
356 		return;
357 	sysctl_ctx_free(&dev->sysctl_ctx);
358 	dev->sysctl_tree = NULL;
359 }
360 
361 /*
362  * /dev/devctl implementation
363  */
364 
365 /*
366  * This design allows only one reader for /dev/devctl.  This is not desirable
367  * in the long run, but will get a lot of hair out of this implementation.
368  * Maybe we should make this device a clonable device.
369  *
370  * Also note: we specifically do not attach a device to the device_t tree
371  * to avoid potential chicken and egg problems.  One could argue that all
372  * of this belongs to the root node.
373  */
374 
375 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
376 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
377 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
378 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
379     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
380 
381 static d_open_t		devopen;
382 static d_close_t	devclose;
383 static d_read_t		devread;
384 static d_ioctl_t	devioctl;
385 static d_poll_t		devpoll;
386 static d_kqfilter_t	devkqfilter;
387 
388 static struct cdevsw dev_cdevsw = {
389 	.d_version =	D_VERSION,
390 	.d_open =	devopen,
391 	.d_close =	devclose,
392 	.d_read =	devread,
393 	.d_ioctl =	devioctl,
394 	.d_poll =	devpoll,
395 	.d_kqfilter =	devkqfilter,
396 	.d_name =	"devctl",
397 };
398 
399 #define DEVCTL_BUFFER (1024 - sizeof(void *))
400 struct dev_event_info {
401 	STAILQ_ENTRY(dev_event_info) dei_link;
402 	char dei_data[DEVCTL_BUFFER];
403 };
404 
405 STAILQ_HEAD(devq, dev_event_info);
406 
407 static struct dev_softc {
408 	int		inuse;
409 	int		nonblock;
410 	int		queued;
411 	int		async;
412 	struct mtx	mtx;
413 	struct cv	cv;
414 	struct selinfo	sel;
415 	struct devq	devq;
416 	struct sigio	*sigio;
417 	uma_zone_t	zone;
418 } devsoftc;
419 
420 static void	filt_devctl_detach(struct knote *kn);
421 static int	filt_devctl_read(struct knote *kn, long hint);
422 
423 struct filterops devctl_rfiltops = {
424 	.f_isfd = 1,
425 	.f_detach = filt_devctl_detach,
426 	.f_event = filt_devctl_read,
427 };
428 
429 static struct cdev *devctl_dev;
430 
431 static void
432 devinit(void)
433 {
434 	int reserve;
435 	uma_zone_t z;
436 
437 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
438 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
439 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
440 	cv_init(&devsoftc.cv, "dev cv");
441 	STAILQ_INIT(&devsoftc.devq);
442 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
443 	if (devctl_queue_length > 0) {
444 		/*
445 		 * Allocate a zone for the messages. Preallocate 2% of these for
446 		 * a reserve. Allow only devctl_queue_length slabs to cap memory
447 		 * usage.  The reserve usually allows coverage of surges of
448 		 * events during memory shortages. Normally we won't have to
449 		 * re-use events from the queue, but will in extreme shortages.
450 		 */
451 		z = devsoftc.zone = uma_zcreate("DEVCTL",
452 		    sizeof(struct dev_event_info), NULL, NULL, NULL, NULL,
453 		    UMA_ALIGN_PTR, 0);
454 		reserve = max(devctl_queue_length / 50, 100);	/* 2% reserve */
455 		uma_zone_set_max(z, devctl_queue_length);
456 		uma_zone_set_maxcache(z, 0);
457 		uma_zone_reserve(z, reserve);
458 		uma_prealloc(z, reserve);
459 	}
460 	devctl2_init();
461 }
462 
463 static int
464 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
465 {
466 	mtx_lock(&devsoftc.mtx);
467 	if (devsoftc.inuse) {
468 		mtx_unlock(&devsoftc.mtx);
469 		return (EBUSY);
470 	}
471 	/* move to init */
472 	devsoftc.inuse = 1;
473 	mtx_unlock(&devsoftc.mtx);
474 	return (0);
475 }
476 
477 static int
478 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
479 {
480 	mtx_lock(&devsoftc.mtx);
481 	devsoftc.inuse = 0;
482 	devsoftc.nonblock = 0;
483 	devsoftc.async = 0;
484 	cv_broadcast(&devsoftc.cv);
485 	funsetown(&devsoftc.sigio);
486 	mtx_unlock(&devsoftc.mtx);
487 	return (0);
488 }
489 
490 /*
491  * The read channel for this device is used to report changes to
492  * userland in realtime.  We are required to free the data as well as
493  * the n1 object because we allocate them separately.  Also note that
494  * we return one record at a time.  If you try to read this device a
495  * character at a time, you will lose the rest of the data.  Listening
496  * programs are expected to cope.
497  */
498 static int
499 devread(struct cdev *dev, struct uio *uio, int ioflag)
500 {
501 	struct dev_event_info *n1;
502 	int rv;
503 
504 	mtx_lock(&devsoftc.mtx);
505 	while (STAILQ_EMPTY(&devsoftc.devq)) {
506 		if (devsoftc.nonblock) {
507 			mtx_unlock(&devsoftc.mtx);
508 			return (EAGAIN);
509 		}
510 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
511 		if (rv) {
512 			/*
513 			 * Need to translate ERESTART to EINTR here? -- jake
514 			 */
515 			mtx_unlock(&devsoftc.mtx);
516 			return (rv);
517 		}
518 	}
519 	n1 = STAILQ_FIRST(&devsoftc.devq);
520 	STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
521 	devsoftc.queued--;
522 	mtx_unlock(&devsoftc.mtx);
523 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
524 	uma_zfree(devsoftc.zone, n1);
525 	return (rv);
526 }
527 
528 static	int
529 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
530 {
531 	switch (cmd) {
532 	case FIONBIO:
533 		if (*(int*)data)
534 			devsoftc.nonblock = 1;
535 		else
536 			devsoftc.nonblock = 0;
537 		return (0);
538 	case FIOASYNC:
539 		if (*(int*)data)
540 			devsoftc.async = 1;
541 		else
542 			devsoftc.async = 0;
543 		return (0);
544 	case FIOSETOWN:
545 		return fsetown(*(int *)data, &devsoftc.sigio);
546 	case FIOGETOWN:
547 		*(int *)data = fgetown(&devsoftc.sigio);
548 		return (0);
549 
550 		/* (un)Support for other fcntl() calls. */
551 	case FIOCLEX:
552 	case FIONCLEX:
553 	case FIONREAD:
554 	default:
555 		break;
556 	}
557 	return (ENOTTY);
558 }
559 
560 static	int
561 devpoll(struct cdev *dev, int events, struct thread *td)
562 {
563 	int	revents = 0;
564 
565 	mtx_lock(&devsoftc.mtx);
566 	if (events & (POLLIN | POLLRDNORM)) {
567 		if (!STAILQ_EMPTY(&devsoftc.devq))
568 			revents = events & (POLLIN | POLLRDNORM);
569 		else
570 			selrecord(td, &devsoftc.sel);
571 	}
572 	mtx_unlock(&devsoftc.mtx);
573 
574 	return (revents);
575 }
576 
577 static int
578 devkqfilter(struct cdev *dev, struct knote *kn)
579 {
580 	int error;
581 
582 	if (kn->kn_filter == EVFILT_READ) {
583 		kn->kn_fop = &devctl_rfiltops;
584 		knlist_add(&devsoftc.sel.si_note, kn, 0);
585 		error = 0;
586 	} else
587 		error = EINVAL;
588 	return (error);
589 }
590 
591 static void
592 filt_devctl_detach(struct knote *kn)
593 {
594 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
595 }
596 
597 static int
598 filt_devctl_read(struct knote *kn, long hint)
599 {
600 	kn->kn_data = devsoftc.queued;
601 	return (kn->kn_data != 0);
602 }
603 
604 /**
605  * @brief Return whether the userland process is running
606  */
607 bool
608 devctl_process_running(void)
609 {
610 	return (devsoftc.inuse == 1);
611 }
612 
613 static struct dev_event_info *
614 devctl_alloc_dei(void)
615 {
616 	struct dev_event_info *dei = NULL;
617 
618 	mtx_lock(&devsoftc.mtx);
619 	if (devctl_queue_length == 0)
620 		goto out;
621 	dei = uma_zalloc(devsoftc.zone, M_NOWAIT);
622 	if (dei == NULL)
623 		dei = uma_zalloc(devsoftc.zone, M_NOWAIT | M_USE_RESERVE);
624 	if (dei == NULL) {
625 		/*
626 		 * Guard against no items in the queue. Normally, this won't
627 		 * happen, but if lots of events happen all at once and there's
628 		 * a chance we're out of allocated space but none have yet been
629 		 * queued when we get here, leaving nothing to steal. This can
630 		 * also happen with error injection. Fail safe by returning
631 		 * NULL in that case..
632 		 */
633 		if (devsoftc.queued == 0)
634 			goto out;
635 		dei = STAILQ_FIRST(&devsoftc.devq);
636 		STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
637 		devsoftc.queued--;
638 	}
639 	MPASS(dei != NULL);
640 	*dei->dei_data = '\0';
641 out:
642 	mtx_unlock(&devsoftc.mtx);
643 	return (dei);
644 }
645 
646 static struct dev_event_info *
647 devctl_alloc_dei_sb(struct sbuf *sb)
648 {
649 	struct dev_event_info *dei;
650 
651 	dei = devctl_alloc_dei();
652 	if (dei != NULL)
653 		sbuf_new(sb, dei->dei_data, sizeof(dei->dei_data), SBUF_FIXEDLEN);
654 	return (dei);
655 }
656 
657 static void
658 devctl_free_dei(struct dev_event_info *dei)
659 {
660 	uma_zfree(devsoftc.zone, dei);
661 }
662 
663 static void
664 devctl_queue(struct dev_event_info *dei)
665 {
666 	mtx_lock(&devsoftc.mtx);
667 	STAILQ_INSERT_TAIL(&devsoftc.devq, dei, dei_link);
668 	devsoftc.queued++;
669 	cv_broadcast(&devsoftc.cv);
670 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
671 	mtx_unlock(&devsoftc.mtx);
672 	selwakeup(&devsoftc.sel);
673 	if (devsoftc.async && devsoftc.sigio != NULL)
674 		pgsigio(&devsoftc.sigio, SIGIO, 0);
675 }
676 
677 /**
678  * @brief Send a 'notification' to userland, using standard ways
679  */
680 void
681 devctl_notify(const char *system, const char *subsystem, const char *type,
682     const char *data)
683 {
684 	struct dev_event_info *dei;
685 	struct sbuf sb;
686 
687 	if (system == NULL || subsystem == NULL || type == NULL)
688 		return;
689 	dei = devctl_alloc_dei_sb(&sb);
690 	if (dei == NULL)
691 		return;
692 	sbuf_cpy(&sb, "!system=");
693 	sbuf_cat(&sb, system);
694 	sbuf_cat(&sb, " subsystem=");
695 	sbuf_cat(&sb, subsystem);
696 	sbuf_cat(&sb, " type=");
697 	sbuf_cat(&sb, type);
698 	if (data != NULL) {
699 		sbuf_putc(&sb, ' ');
700 		sbuf_cat(&sb, data);
701 	}
702 	sbuf_putc(&sb, '\n');
703 	if (sbuf_finish(&sb) != 0)
704 		devctl_free_dei(dei);	/* overflow -> drop it */
705 	else
706 		devctl_queue(dei);
707 }
708 
709 /*
710  * Common routine that tries to make sending messages as easy as possible.
711  * We allocate memory for the data, copy strings into that, but do not
712  * free it unless there's an error.  The dequeue part of the driver should
713  * free the data.  We don't send data when the device is disabled.  We do
714  * send data, even when we have no listeners, because we wish to avoid
715  * races relating to startup and restart of listening applications.
716  *
717  * devaddq is designed to string together the type of event, with the
718  * object of that event, plus the plug and play info and location info
719  * for that event.  This is likely most useful for devices, but less
720  * useful for other consumers of this interface.  Those should use
721  * the devctl_notify() interface instead.
722  *
723  * Output:
724  *	${type}${what} at $(location dev) $(pnp-info dev) on $(parent dev)
725  */
726 static void
727 devaddq(const char *type, const char *what, device_t dev)
728 {
729 	struct dev_event_info *dei;
730 	const char *parstr;
731 	struct sbuf sb;
732 
733 	dei = devctl_alloc_dei_sb(&sb);
734 	if (dei == NULL)
735 		return;
736 	sbuf_cpy(&sb, type);
737 	sbuf_cat(&sb, what);
738 	sbuf_cat(&sb, " at ");
739 
740 	/* Add in the location */
741 	bus_child_location(dev, &sb);
742 	sbuf_putc(&sb, ' ');
743 
744 	/* Add in pnpinfo */
745 	bus_child_pnpinfo(dev, &sb);
746 
747 	/* Get the parent of this device, or / if high enough in the tree. */
748 	if (device_get_parent(dev) == NULL)
749 		parstr = ".";	/* Or '/' ? */
750 	else
751 		parstr = device_get_nameunit(device_get_parent(dev));
752 	sbuf_cat(&sb, " on ");
753 	sbuf_cat(&sb, parstr);
754 	sbuf_putc(&sb, '\n');
755 	if (sbuf_finish(&sb) != 0)
756 		goto bad;
757 	devctl_queue(dei);
758 	return;
759 bad:
760 	devctl_free_dei(dei);
761 }
762 
763 /*
764  * A device was added to the tree.  We are called just after it successfully
765  * attaches (that is, probe and attach success for this device).  No call
766  * is made if a device is merely parented into the tree.  See devnomatch
767  * if probe fails.  If attach fails, no notification is sent (but maybe
768  * we should have a different message for this).
769  */
770 static void
771 devadded(device_t dev)
772 {
773 	devaddq("+", device_get_nameunit(dev), dev);
774 }
775 
776 /*
777  * A device was removed from the tree.  We are called just before this
778  * happens.
779  */
780 static void
781 devremoved(device_t dev)
782 {
783 	devaddq("-", device_get_nameunit(dev), dev);
784 }
785 
786 /*
787  * Called when there's no match for this device.  This is only called
788  * the first time that no match happens, so we don't keep getting this
789  * message.  Should that prove to be undesirable, we can change it.
790  * This is called when all drivers that can attach to a given bus
791  * decline to accept this device.  Other errors may not be detected.
792  */
793 static void
794 devnomatch(device_t dev)
795 {
796 	devaddq("?", "", dev);
797 }
798 
799 static int
800 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
801 {
802 	int q, error;
803 
804 	q = devctl_queue_length;
805 	error = sysctl_handle_int(oidp, &q, 0, req);
806 	if (error || !req->newptr)
807 		return (error);
808 	if (q < 0)
809 		return (EINVAL);
810 
811 	/*
812 	 * When set as a tunable, we've not yet initialized the mutex.
813 	 * It is safe to just assign to devctl_queue_length and return
814 	 * as we're racing no one. We'll use whatever value set in
815 	 * devinit.
816 	 */
817 	if (!mtx_initialized(&devsoftc.mtx)) {
818 		devctl_queue_length = q;
819 		return (0);
820 	}
821 
822 	/*
823 	 * XXX It's hard to grow or shrink the UMA zone. Only allow
824 	 * disabling the queue size for the moment until underlying
825 	 * UMA issues can be sorted out.
826 	 */
827 	if (q != 0)
828 		return (EINVAL);
829 	if (q == devctl_queue_length)
830 		return (0);
831 	mtx_lock(&devsoftc.mtx);
832 	devctl_queue_length = 0;
833 	uma_zdestroy(devsoftc.zone);
834 	devsoftc.zone = 0;
835 	mtx_unlock(&devsoftc.mtx);
836 	return (0);
837 }
838 
839 /**
840  * @brief safely quotes strings that might have double quotes in them.
841  *
842  * The devctl protocol relies on quoted strings having matching quotes.
843  * This routine quotes any internal quotes so the resulting string
844  * is safe to pass to snprintf to construct, for example pnp info strings.
845  *
846  * @param sb	sbuf to place the characters into
847  * @param src	Original buffer.
848  */
849 void
850 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
851 {
852 	while (*src != '\0') {
853 		if (*src == '"' || *src == '\\')
854 			sbuf_putc(sb, '\\');
855 		sbuf_putc(sb, *src++);
856 	}
857 }
858 
859 /* End of /dev/devctl code */
860 
861 static struct device_list bus_data_devices;
862 static int bus_data_generation = 1;
863 
864 static kobj_method_t null_methods[] = {
865 	KOBJMETHOD_END
866 };
867 
868 DEFINE_CLASS(null, null_methods, 0);
869 
870 void
871 bus_topo_assert(void)
872 {
873 
874 	GIANT_REQUIRED;
875 }
876 
877 struct mtx *
878 bus_topo_mtx(void)
879 {
880 
881 	return (&Giant);
882 }
883 
884 void
885 bus_topo_lock(void)
886 {
887 
888 	mtx_lock(bus_topo_mtx());
889 }
890 
891 void
892 bus_topo_unlock(void)
893 {
894 
895 	mtx_unlock(bus_topo_mtx());
896 }
897 
898 /*
899  * Bus pass implementation
900  */
901 
902 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
903 int bus_current_pass = BUS_PASS_ROOT;
904 
905 /**
906  * @internal
907  * @brief Register the pass level of a new driver attachment
908  *
909  * Register a new driver attachment's pass level.  If no driver
910  * attachment with the same pass level has been added, then @p new
911  * will be added to the global passes list.
912  *
913  * @param new		the new driver attachment
914  */
915 static void
916 driver_register_pass(struct driverlink *new)
917 {
918 	struct driverlink *dl;
919 
920 	/* We only consider pass numbers during boot. */
921 	if (bus_current_pass == BUS_PASS_DEFAULT)
922 		return;
923 
924 	/*
925 	 * Walk the passes list.  If we already know about this pass
926 	 * then there is nothing to do.  If we don't, then insert this
927 	 * driver link into the list.
928 	 */
929 	TAILQ_FOREACH(dl, &passes, passlink) {
930 		if (dl->pass < new->pass)
931 			continue;
932 		if (dl->pass == new->pass)
933 			return;
934 		TAILQ_INSERT_BEFORE(dl, new, passlink);
935 		return;
936 	}
937 	TAILQ_INSERT_TAIL(&passes, new, passlink);
938 }
939 
940 /**
941  * @brief Raise the current bus pass
942  *
943  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
944  * method on the root bus to kick off a new device tree scan for each
945  * new pass level that has at least one driver.
946  */
947 void
948 bus_set_pass(int pass)
949 {
950 	struct driverlink *dl;
951 
952 	if (bus_current_pass > pass)
953 		panic("Attempt to lower bus pass level");
954 
955 	TAILQ_FOREACH(dl, &passes, passlink) {
956 		/* Skip pass values below the current pass level. */
957 		if (dl->pass <= bus_current_pass)
958 			continue;
959 
960 		/*
961 		 * Bail once we hit a driver with a pass level that is
962 		 * too high.
963 		 */
964 		if (dl->pass > pass)
965 			break;
966 
967 		/*
968 		 * Raise the pass level to the next level and rescan
969 		 * the tree.
970 		 */
971 		bus_current_pass = dl->pass;
972 		BUS_NEW_PASS(root_bus);
973 	}
974 
975 	/*
976 	 * If there isn't a driver registered for the requested pass,
977 	 * then bus_current_pass might still be less than 'pass'.  Set
978 	 * it to 'pass' in that case.
979 	 */
980 	if (bus_current_pass < pass)
981 		bus_current_pass = pass;
982 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
983 }
984 
985 /*
986  * Devclass implementation
987  */
988 
989 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
990 
991 /**
992  * @internal
993  * @brief Find or create a device class
994  *
995  * If a device class with the name @p classname exists, return it,
996  * otherwise if @p create is non-zero create and return a new device
997  * class.
998  *
999  * If @p parentname is non-NULL, the parent of the devclass is set to
1000  * the devclass of that name.
1001  *
1002  * @param classname	the devclass name to find or create
1003  * @param parentname	the parent devclass name or @c NULL
1004  * @param create	non-zero to create a devclass
1005  */
1006 static devclass_t
1007 devclass_find_internal(const char *classname, const char *parentname,
1008 		       int create)
1009 {
1010 	devclass_t dc;
1011 
1012 	PDEBUG(("looking for %s", classname));
1013 	if (!classname)
1014 		return (NULL);
1015 
1016 	TAILQ_FOREACH(dc, &devclasses, link) {
1017 		if (!strcmp(dc->name, classname))
1018 			break;
1019 	}
1020 
1021 	if (create && !dc) {
1022 		PDEBUG(("creating %s", classname));
1023 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1024 		    M_BUS, M_NOWAIT | M_ZERO);
1025 		if (!dc)
1026 			return (NULL);
1027 		dc->parent = NULL;
1028 		dc->name = (char*) (dc + 1);
1029 		strcpy(dc->name, classname);
1030 		TAILQ_INIT(&dc->drivers);
1031 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1032 
1033 		bus_data_generation_update();
1034 	}
1035 
1036 	/*
1037 	 * If a parent class is specified, then set that as our parent so
1038 	 * that this devclass will support drivers for the parent class as
1039 	 * well.  If the parent class has the same name don't do this though
1040 	 * as it creates a cycle that can trigger an infinite loop in
1041 	 * device_probe_child() if a device exists for which there is no
1042 	 * suitable driver.
1043 	 */
1044 	if (parentname && dc && !dc->parent &&
1045 	    strcmp(classname, parentname) != 0) {
1046 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1047 		dc->parent->flags |= DC_HAS_CHILDREN;
1048 	}
1049 
1050 	return (dc);
1051 }
1052 
1053 /**
1054  * @brief Create a device class
1055  *
1056  * If a device class with the name @p classname exists, return it,
1057  * otherwise create and return a new device class.
1058  *
1059  * @param classname	the devclass name to find or create
1060  */
1061 devclass_t
1062 devclass_create(const char *classname)
1063 {
1064 	return (devclass_find_internal(classname, NULL, TRUE));
1065 }
1066 
1067 /**
1068  * @brief Find a device class
1069  *
1070  * If a device class with the name @p classname exists, return it,
1071  * otherwise return @c NULL.
1072  *
1073  * @param classname	the devclass name to find
1074  */
1075 devclass_t
1076 devclass_find(const char *classname)
1077 {
1078 	return (devclass_find_internal(classname, NULL, FALSE));
1079 }
1080 
1081 /**
1082  * @brief Register that a device driver has been added to a devclass
1083  *
1084  * Register that a device driver has been added to a devclass.  This
1085  * is called by devclass_add_driver to accomplish the recursive
1086  * notification of all the children classes of dc, as well as dc.
1087  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1088  * the devclass.
1089  *
1090  * We do a full search here of the devclass list at each iteration
1091  * level to save storing children-lists in the devclass structure.  If
1092  * we ever move beyond a few dozen devices doing this, we may need to
1093  * reevaluate...
1094  *
1095  * @param dc		the devclass to edit
1096  * @param driver	the driver that was just added
1097  */
1098 static void
1099 devclass_driver_added(devclass_t dc, driver_t *driver)
1100 {
1101 	devclass_t parent;
1102 	int i;
1103 
1104 	/*
1105 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1106 	 */
1107 	for (i = 0; i < dc->maxunit; i++)
1108 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1109 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1110 
1111 	/*
1112 	 * Walk through the children classes.  Since we only keep a
1113 	 * single parent pointer around, we walk the entire list of
1114 	 * devclasses looking for children.  We set the
1115 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1116 	 * the parent, so we only walk the list for those devclasses
1117 	 * that have children.
1118 	 */
1119 	if (!(dc->flags & DC_HAS_CHILDREN))
1120 		return;
1121 	parent = dc;
1122 	TAILQ_FOREACH(dc, &devclasses, link) {
1123 		if (dc->parent == parent)
1124 			devclass_driver_added(dc, driver);
1125 	}
1126 }
1127 
1128 /**
1129  * @brief Add a device driver to a device class
1130  *
1131  * Add a device driver to a devclass. This is normally called
1132  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1133  * all devices in the devclass will be called to allow them to attempt
1134  * to re-probe any unmatched children.
1135  *
1136  * @param dc		the devclass to edit
1137  * @param driver	the driver to register
1138  */
1139 int
1140 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1141 {
1142 	driverlink_t dl;
1143 	devclass_t child_dc;
1144 	const char *parentname;
1145 
1146 	PDEBUG(("%s", DRIVERNAME(driver)));
1147 
1148 	/* Don't allow invalid pass values. */
1149 	if (pass <= BUS_PASS_ROOT)
1150 		return (EINVAL);
1151 
1152 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1153 	if (!dl)
1154 		return (ENOMEM);
1155 
1156 	/*
1157 	 * Compile the driver's methods. Also increase the reference count
1158 	 * so that the class doesn't get freed when the last instance
1159 	 * goes. This means we can safely use static methods and avoids a
1160 	 * double-free in devclass_delete_driver.
1161 	 */
1162 	kobj_class_compile((kobj_class_t) driver);
1163 
1164 	/*
1165 	 * If the driver has any base classes, make the
1166 	 * devclass inherit from the devclass of the driver's
1167 	 * first base class. This will allow the system to
1168 	 * search for drivers in both devclasses for children
1169 	 * of a device using this driver.
1170 	 */
1171 	if (driver->baseclasses)
1172 		parentname = driver->baseclasses[0]->name;
1173 	else
1174 		parentname = NULL;
1175 	child_dc = devclass_find_internal(driver->name, parentname, TRUE);
1176 	if (dcp != NULL)
1177 		*dcp = child_dc;
1178 
1179 	dl->driver = driver;
1180 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1181 	driver->refs++;		/* XXX: kobj_mtx */
1182 	dl->pass = pass;
1183 	driver_register_pass(dl);
1184 
1185 	if (device_frozen) {
1186 		dl->flags |= DL_DEFERRED_PROBE;
1187 	} else {
1188 		devclass_driver_added(dc, driver);
1189 	}
1190 	bus_data_generation_update();
1191 	return (0);
1192 }
1193 
1194 /**
1195  * @brief Register that a device driver has been deleted from a devclass
1196  *
1197  * Register that a device driver has been removed from a devclass.
1198  * This is called by devclass_delete_driver to accomplish the
1199  * recursive notification of all the children classes of busclass, as
1200  * well as busclass.  Each layer will attempt to detach the driver
1201  * from any devices that are children of the bus's devclass.  The function
1202  * will return an error if a device fails to detach.
1203  *
1204  * We do a full search here of the devclass list at each iteration
1205  * level to save storing children-lists in the devclass structure.  If
1206  * we ever move beyond a few dozen devices doing this, we may need to
1207  * reevaluate...
1208  *
1209  * @param busclass	the devclass of the parent bus
1210  * @param dc		the devclass of the driver being deleted
1211  * @param driver	the driver being deleted
1212  */
1213 static int
1214 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1215 {
1216 	devclass_t parent;
1217 	device_t dev;
1218 	int error, i;
1219 
1220 	/*
1221 	 * Disassociate from any devices.  We iterate through all the
1222 	 * devices in the devclass of the driver and detach any which are
1223 	 * using the driver and which have a parent in the devclass which
1224 	 * we are deleting from.
1225 	 *
1226 	 * Note that since a driver can be in multiple devclasses, we
1227 	 * should not detach devices which are not children of devices in
1228 	 * the affected devclass.
1229 	 *
1230 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1231 	 * generate later.
1232 	 */
1233 	for (i = 0; i < dc->maxunit; i++) {
1234 		if (dc->devices[i]) {
1235 			dev = dc->devices[i];
1236 			if (dev->driver == driver && dev->parent &&
1237 			    dev->parent->devclass == busclass) {
1238 				if ((error = device_detach(dev)) != 0)
1239 					return (error);
1240 				if (device_frozen) {
1241 					dev->flags &= ~DF_DONENOMATCH;
1242 					dev->flags |= DF_NEEDNOMATCH;
1243 				} else {
1244 					BUS_PROBE_NOMATCH(dev->parent, dev);
1245 					devnomatch(dev);
1246 					dev->flags |= DF_DONENOMATCH;
1247 				}
1248 			}
1249 		}
1250 	}
1251 
1252 	/*
1253 	 * Walk through the children classes.  Since we only keep a
1254 	 * single parent pointer around, we walk the entire list of
1255 	 * devclasses looking for children.  We set the
1256 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1257 	 * the parent, so we only walk the list for those devclasses
1258 	 * that have children.
1259 	 */
1260 	if (!(busclass->flags & DC_HAS_CHILDREN))
1261 		return (0);
1262 	parent = busclass;
1263 	TAILQ_FOREACH(busclass, &devclasses, link) {
1264 		if (busclass->parent == parent) {
1265 			error = devclass_driver_deleted(busclass, dc, driver);
1266 			if (error)
1267 				return (error);
1268 		}
1269 	}
1270 	return (0);
1271 }
1272 
1273 /**
1274  * @brief Delete a device driver from a device class
1275  *
1276  * Delete a device driver from a devclass. This is normally called
1277  * automatically by DRIVER_MODULE().
1278  *
1279  * If the driver is currently attached to any devices,
1280  * devclass_delete_driver() will first attempt to detach from each
1281  * device. If one of the detach calls fails, the driver will not be
1282  * deleted.
1283  *
1284  * @param dc		the devclass to edit
1285  * @param driver	the driver to unregister
1286  */
1287 int
1288 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1289 {
1290 	devclass_t dc = devclass_find(driver->name);
1291 	driverlink_t dl;
1292 	int error;
1293 
1294 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1295 
1296 	if (!dc)
1297 		return (0);
1298 
1299 	/*
1300 	 * Find the link structure in the bus' list of drivers.
1301 	 */
1302 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1303 		if (dl->driver == driver)
1304 			break;
1305 	}
1306 
1307 	if (!dl) {
1308 		PDEBUG(("%s not found in %s list", driver->name,
1309 		    busclass->name));
1310 		return (ENOENT);
1311 	}
1312 
1313 	error = devclass_driver_deleted(busclass, dc, driver);
1314 	if (error != 0)
1315 		return (error);
1316 
1317 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1318 	free(dl, M_BUS);
1319 
1320 	/* XXX: kobj_mtx */
1321 	driver->refs--;
1322 	if (driver->refs == 0)
1323 		kobj_class_free((kobj_class_t) driver);
1324 
1325 	bus_data_generation_update();
1326 	return (0);
1327 }
1328 
1329 /**
1330  * @brief Quiesces a set of device drivers from a device class
1331  *
1332  * Quiesce a device driver from a devclass. This is normally called
1333  * automatically by DRIVER_MODULE().
1334  *
1335  * If the driver is currently attached to any devices,
1336  * devclass_quiesece_driver() will first attempt to quiesce each
1337  * device.
1338  *
1339  * @param dc		the devclass to edit
1340  * @param driver	the driver to unregister
1341  */
1342 static int
1343 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1344 {
1345 	devclass_t dc = devclass_find(driver->name);
1346 	driverlink_t dl;
1347 	device_t dev;
1348 	int i;
1349 	int error;
1350 
1351 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1352 
1353 	if (!dc)
1354 		return (0);
1355 
1356 	/*
1357 	 * Find the link structure in the bus' list of drivers.
1358 	 */
1359 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1360 		if (dl->driver == driver)
1361 			break;
1362 	}
1363 
1364 	if (!dl) {
1365 		PDEBUG(("%s not found in %s list", driver->name,
1366 		    busclass->name));
1367 		return (ENOENT);
1368 	}
1369 
1370 	/*
1371 	 * Quiesce all devices.  We iterate through all the devices in
1372 	 * the devclass of the driver and quiesce any which are using
1373 	 * the driver and which have a parent in the devclass which we
1374 	 * are quiescing.
1375 	 *
1376 	 * Note that since a driver can be in multiple devclasses, we
1377 	 * should not quiesce devices which are not children of
1378 	 * devices in the affected devclass.
1379 	 */
1380 	for (i = 0; i < dc->maxunit; i++) {
1381 		if (dc->devices[i]) {
1382 			dev = dc->devices[i];
1383 			if (dev->driver == driver && dev->parent &&
1384 			    dev->parent->devclass == busclass) {
1385 				if ((error = device_quiesce(dev)) != 0)
1386 					return (error);
1387 			}
1388 		}
1389 	}
1390 
1391 	return (0);
1392 }
1393 
1394 /**
1395  * @internal
1396  */
1397 static driverlink_t
1398 devclass_find_driver_internal(devclass_t dc, const char *classname)
1399 {
1400 	driverlink_t dl;
1401 
1402 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1403 
1404 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1405 		if (!strcmp(dl->driver->name, classname))
1406 			return (dl);
1407 	}
1408 
1409 	PDEBUG(("not found"));
1410 	return (NULL);
1411 }
1412 
1413 /**
1414  * @brief Return the name of the devclass
1415  */
1416 const char *
1417 devclass_get_name(devclass_t dc)
1418 {
1419 	return (dc->name);
1420 }
1421 
1422 /**
1423  * @brief Find a device given a unit number
1424  *
1425  * @param dc		the devclass to search
1426  * @param unit		the unit number to search for
1427  *
1428  * @returns		the device with the given unit number or @c
1429  *			NULL if there is no such device
1430  */
1431 device_t
1432 devclass_get_device(devclass_t dc, int unit)
1433 {
1434 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1435 		return (NULL);
1436 	return (dc->devices[unit]);
1437 }
1438 
1439 /**
1440  * @brief Find the softc field of a device given a unit number
1441  *
1442  * @param dc		the devclass to search
1443  * @param unit		the unit number to search for
1444  *
1445  * @returns		the softc field of the device with the given
1446  *			unit number or @c NULL if there is no such
1447  *			device
1448  */
1449 void *
1450 devclass_get_softc(devclass_t dc, int unit)
1451 {
1452 	device_t dev;
1453 
1454 	dev = devclass_get_device(dc, unit);
1455 	if (!dev)
1456 		return (NULL);
1457 
1458 	return (device_get_softc(dev));
1459 }
1460 
1461 /**
1462  * @brief Get a list of devices in the devclass
1463  *
1464  * An array containing a list of all the devices in the given devclass
1465  * is allocated and returned in @p *devlistp. The number of devices
1466  * in the array is returned in @p *devcountp. The caller should free
1467  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1468  *
1469  * @param dc		the devclass to examine
1470  * @param devlistp	points at location for array pointer return
1471  *			value
1472  * @param devcountp	points at location for array size return value
1473  *
1474  * @retval 0		success
1475  * @retval ENOMEM	the array allocation failed
1476  */
1477 int
1478 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1479 {
1480 	int count, i;
1481 	device_t *list;
1482 
1483 	count = devclass_get_count(dc);
1484 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1485 	if (!list)
1486 		return (ENOMEM);
1487 
1488 	count = 0;
1489 	for (i = 0; i < dc->maxunit; i++) {
1490 		if (dc->devices[i]) {
1491 			list[count] = dc->devices[i];
1492 			count++;
1493 		}
1494 	}
1495 
1496 	*devlistp = list;
1497 	*devcountp = count;
1498 
1499 	return (0);
1500 }
1501 
1502 /**
1503  * @brief Get a list of drivers in the devclass
1504  *
1505  * An array containing a list of pointers to all the drivers in the
1506  * given devclass is allocated and returned in @p *listp.  The number
1507  * of drivers in the array is returned in @p *countp. The caller should
1508  * free the array using @c free(p, M_TEMP).
1509  *
1510  * @param dc		the devclass to examine
1511  * @param listp		gives location for array pointer return value
1512  * @param countp	gives location for number of array elements
1513  *			return value
1514  *
1515  * @retval 0		success
1516  * @retval ENOMEM	the array allocation failed
1517  */
1518 int
1519 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1520 {
1521 	driverlink_t dl;
1522 	driver_t **list;
1523 	int count;
1524 
1525 	count = 0;
1526 	TAILQ_FOREACH(dl, &dc->drivers, link)
1527 		count++;
1528 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1529 	if (list == NULL)
1530 		return (ENOMEM);
1531 
1532 	count = 0;
1533 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1534 		list[count] = dl->driver;
1535 		count++;
1536 	}
1537 	*listp = list;
1538 	*countp = count;
1539 
1540 	return (0);
1541 }
1542 
1543 /**
1544  * @brief Get the number of devices in a devclass
1545  *
1546  * @param dc		the devclass to examine
1547  */
1548 int
1549 devclass_get_count(devclass_t dc)
1550 {
1551 	int count, i;
1552 
1553 	count = 0;
1554 	for (i = 0; i < dc->maxunit; i++)
1555 		if (dc->devices[i])
1556 			count++;
1557 	return (count);
1558 }
1559 
1560 /**
1561  * @brief Get the maximum unit number used in a devclass
1562  *
1563  * Note that this is one greater than the highest currently-allocated
1564  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1565  * that not even the devclass has been allocated yet.
1566  *
1567  * @param dc		the devclass to examine
1568  */
1569 int
1570 devclass_get_maxunit(devclass_t dc)
1571 {
1572 	if (dc == NULL)
1573 		return (-1);
1574 	return (dc->maxunit);
1575 }
1576 
1577 /**
1578  * @brief Find a free unit number in a devclass
1579  *
1580  * This function searches for the first unused unit number greater
1581  * that or equal to @p unit.
1582  *
1583  * @param dc		the devclass to examine
1584  * @param unit		the first unit number to check
1585  */
1586 int
1587 devclass_find_free_unit(devclass_t dc, int unit)
1588 {
1589 	if (dc == NULL)
1590 		return (unit);
1591 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1592 		unit++;
1593 	return (unit);
1594 }
1595 
1596 /**
1597  * @brief Set the parent of a devclass
1598  *
1599  * The parent class is normally initialised automatically by
1600  * DRIVER_MODULE().
1601  *
1602  * @param dc		the devclass to edit
1603  * @param pdc		the new parent devclass
1604  */
1605 void
1606 devclass_set_parent(devclass_t dc, devclass_t pdc)
1607 {
1608 	dc->parent = pdc;
1609 }
1610 
1611 /**
1612  * @brief Get the parent of a devclass
1613  *
1614  * @param dc		the devclass to examine
1615  */
1616 devclass_t
1617 devclass_get_parent(devclass_t dc)
1618 {
1619 	return (dc->parent);
1620 }
1621 
1622 struct sysctl_ctx_list *
1623 devclass_get_sysctl_ctx(devclass_t dc)
1624 {
1625 	return (&dc->sysctl_ctx);
1626 }
1627 
1628 struct sysctl_oid *
1629 devclass_get_sysctl_tree(devclass_t dc)
1630 {
1631 	return (dc->sysctl_tree);
1632 }
1633 
1634 /**
1635  * @internal
1636  * @brief Allocate a unit number
1637  *
1638  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1639  * will do). The allocated unit number is returned in @p *unitp.
1640 
1641  * @param dc		the devclass to allocate from
1642  * @param unitp		points at the location for the allocated unit
1643  *			number
1644  *
1645  * @retval 0		success
1646  * @retval EEXIST	the requested unit number is already allocated
1647  * @retval ENOMEM	memory allocation failure
1648  */
1649 static int
1650 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1651 {
1652 	const char *s;
1653 	int unit = *unitp;
1654 
1655 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1656 
1657 	/* Ask the parent bus if it wants to wire this device. */
1658 	if (unit == -1)
1659 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1660 		    &unit);
1661 
1662 	/* If we were given a wired unit number, check for existing device */
1663 	/* XXX imp XXX */
1664 	if (unit != -1) {
1665 		if (unit >= 0 && unit < dc->maxunit &&
1666 		    dc->devices[unit] != NULL) {
1667 			if (bootverbose)
1668 				printf("%s: %s%d already exists; skipping it\n",
1669 				    dc->name, dc->name, *unitp);
1670 			return (EEXIST);
1671 		}
1672 	} else {
1673 		/* Unwired device, find the next available slot for it */
1674 		unit = 0;
1675 		for (unit = 0;; unit++) {
1676 			/* If this device slot is already in use, skip it. */
1677 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1678 				continue;
1679 
1680 			/* If there is an "at" hint for a unit then skip it. */
1681 			if (resource_string_value(dc->name, unit, "at", &s) ==
1682 			    0)
1683 				continue;
1684 
1685 			break;
1686 		}
1687 	}
1688 
1689 	/*
1690 	 * We've selected a unit beyond the length of the table, so let's
1691 	 * extend the table to make room for all units up to and including
1692 	 * this one.
1693 	 */
1694 	if (unit >= dc->maxunit) {
1695 		device_t *newlist, *oldlist;
1696 		int newsize;
1697 
1698 		oldlist = dc->devices;
1699 		newsize = roundup((unit + 1),
1700 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1701 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1702 		if (!newlist)
1703 			return (ENOMEM);
1704 		if (oldlist != NULL)
1705 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1706 		bzero(newlist + dc->maxunit,
1707 		    sizeof(device_t) * (newsize - dc->maxunit));
1708 		dc->devices = newlist;
1709 		dc->maxunit = newsize;
1710 		if (oldlist != NULL)
1711 			free(oldlist, M_BUS);
1712 	}
1713 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1714 
1715 	*unitp = unit;
1716 	return (0);
1717 }
1718 
1719 /**
1720  * @internal
1721  * @brief Add a device to a devclass
1722  *
1723  * A unit number is allocated for the device (using the device's
1724  * preferred unit number if any) and the device is registered in the
1725  * devclass. This allows the device to be looked up by its unit
1726  * number, e.g. by decoding a dev_t minor number.
1727  *
1728  * @param dc		the devclass to add to
1729  * @param dev		the device to add
1730  *
1731  * @retval 0		success
1732  * @retval EEXIST	the requested unit number is already allocated
1733  * @retval ENOMEM	memory allocation failure
1734  */
1735 static int
1736 devclass_add_device(devclass_t dc, device_t dev)
1737 {
1738 	int buflen, error;
1739 
1740 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1741 
1742 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1743 	if (buflen < 0)
1744 		return (ENOMEM);
1745 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1746 	if (!dev->nameunit)
1747 		return (ENOMEM);
1748 
1749 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1750 		free(dev->nameunit, M_BUS);
1751 		dev->nameunit = NULL;
1752 		return (error);
1753 	}
1754 	dc->devices[dev->unit] = dev;
1755 	dev->devclass = dc;
1756 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1757 
1758 	return (0);
1759 }
1760 
1761 /**
1762  * @internal
1763  * @brief Delete a device from a devclass
1764  *
1765  * The device is removed from the devclass's device list and its unit
1766  * number is freed.
1767 
1768  * @param dc		the devclass to delete from
1769  * @param dev		the device to delete
1770  *
1771  * @retval 0		success
1772  */
1773 static int
1774 devclass_delete_device(devclass_t dc, device_t dev)
1775 {
1776 	if (!dc || !dev)
1777 		return (0);
1778 
1779 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1780 
1781 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1782 		panic("devclass_delete_device: inconsistent device class");
1783 	dc->devices[dev->unit] = NULL;
1784 	if (dev->flags & DF_WILDCARD)
1785 		dev->unit = -1;
1786 	dev->devclass = NULL;
1787 	free(dev->nameunit, M_BUS);
1788 	dev->nameunit = NULL;
1789 
1790 	return (0);
1791 }
1792 
1793 /**
1794  * @internal
1795  * @brief Make a new device and add it as a child of @p parent
1796  *
1797  * @param parent	the parent of the new device
1798  * @param name		the devclass name of the new device or @c NULL
1799  *			to leave the devclass unspecified
1800  * @parem unit		the unit number of the new device of @c -1 to
1801  *			leave the unit number unspecified
1802  *
1803  * @returns the new device
1804  */
1805 static device_t
1806 make_device(device_t parent, const char *name, int unit)
1807 {
1808 	device_t dev;
1809 	devclass_t dc;
1810 
1811 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1812 
1813 	if (name) {
1814 		dc = devclass_find_internal(name, NULL, TRUE);
1815 		if (!dc) {
1816 			printf("make_device: can't find device class %s\n",
1817 			    name);
1818 			return (NULL);
1819 		}
1820 	} else {
1821 		dc = NULL;
1822 	}
1823 
1824 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1825 	if (!dev)
1826 		return (NULL);
1827 
1828 	dev->parent = parent;
1829 	TAILQ_INIT(&dev->children);
1830 	kobj_init((kobj_t) dev, &null_class);
1831 	dev->driver = NULL;
1832 	dev->devclass = NULL;
1833 	dev->unit = unit;
1834 	dev->nameunit = NULL;
1835 	dev->desc = NULL;
1836 	dev->busy = 0;
1837 	dev->devflags = 0;
1838 	dev->flags = DF_ENABLED;
1839 	dev->order = 0;
1840 	if (unit == -1)
1841 		dev->flags |= DF_WILDCARD;
1842 	if (name) {
1843 		dev->flags |= DF_FIXEDCLASS;
1844 		if (devclass_add_device(dc, dev)) {
1845 			kobj_delete((kobj_t) dev, M_BUS);
1846 			return (NULL);
1847 		}
1848 	}
1849 	if (parent != NULL && device_has_quiet_children(parent))
1850 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1851 	dev->ivars = NULL;
1852 	dev->softc = NULL;
1853 
1854 	dev->state = DS_NOTPRESENT;
1855 
1856 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1857 	bus_data_generation_update();
1858 
1859 	return (dev);
1860 }
1861 
1862 /**
1863  * @internal
1864  * @brief Print a description of a device.
1865  */
1866 static int
1867 device_print_child(device_t dev, device_t child)
1868 {
1869 	int retval = 0;
1870 
1871 	if (device_is_alive(child))
1872 		retval += BUS_PRINT_CHILD(dev, child);
1873 	else
1874 		retval += device_printf(child, " not found\n");
1875 
1876 	return (retval);
1877 }
1878 
1879 /**
1880  * @brief Create a new device
1881  *
1882  * This creates a new device and adds it as a child of an existing
1883  * parent device. The new device will be added after the last existing
1884  * child with order zero.
1885  *
1886  * @param dev		the device which will be the parent of the
1887  *			new child device
1888  * @param name		devclass name for new device or @c NULL if not
1889  *			specified
1890  * @param unit		unit number for new device or @c -1 if not
1891  *			specified
1892  *
1893  * @returns		the new device
1894  */
1895 device_t
1896 device_add_child(device_t dev, const char *name, int unit)
1897 {
1898 	return (device_add_child_ordered(dev, 0, name, unit));
1899 }
1900 
1901 /**
1902  * @brief Create a new device
1903  *
1904  * This creates a new device and adds it as a child of an existing
1905  * parent device. The new device will be added after the last existing
1906  * child with the same order.
1907  *
1908  * @param dev		the device which will be the parent of the
1909  *			new child device
1910  * @param order		a value which is used to partially sort the
1911  *			children of @p dev - devices created using
1912  *			lower values of @p order appear first in @p
1913  *			dev's list of children
1914  * @param name		devclass name for new device or @c NULL if not
1915  *			specified
1916  * @param unit		unit number for new device or @c -1 if not
1917  *			specified
1918  *
1919  * @returns		the new device
1920  */
1921 device_t
1922 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1923 {
1924 	device_t child;
1925 	device_t place;
1926 
1927 	PDEBUG(("%s at %s with order %u as unit %d",
1928 	    name, DEVICENAME(dev), order, unit));
1929 	KASSERT(name != NULL || unit == -1,
1930 	    ("child device with wildcard name and specific unit number"));
1931 
1932 	child = make_device(dev, name, unit);
1933 	if (child == NULL)
1934 		return (child);
1935 	child->order = order;
1936 
1937 	TAILQ_FOREACH(place, &dev->children, link) {
1938 		if (place->order > order)
1939 			break;
1940 	}
1941 
1942 	if (place) {
1943 		/*
1944 		 * The device 'place' is the first device whose order is
1945 		 * greater than the new child.
1946 		 */
1947 		TAILQ_INSERT_BEFORE(place, child, link);
1948 	} else {
1949 		/*
1950 		 * The new child's order is greater or equal to the order of
1951 		 * any existing device. Add the child to the tail of the list.
1952 		 */
1953 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1954 	}
1955 
1956 	bus_data_generation_update();
1957 	return (child);
1958 }
1959 
1960 /**
1961  * @brief Delete a device
1962  *
1963  * This function deletes a device along with all of its children. If
1964  * the device currently has a driver attached to it, the device is
1965  * detached first using device_detach().
1966  *
1967  * @param dev		the parent device
1968  * @param child		the device to delete
1969  *
1970  * @retval 0		success
1971  * @retval non-zero	a unit error code describing the error
1972  */
1973 int
1974 device_delete_child(device_t dev, device_t child)
1975 {
1976 	int error;
1977 	device_t grandchild;
1978 
1979 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1980 
1981 	/* detach parent before deleting children, if any */
1982 	if ((error = device_detach(child)) != 0)
1983 		return (error);
1984 
1985 	/* remove children second */
1986 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1987 		error = device_delete_child(child, grandchild);
1988 		if (error)
1989 			return (error);
1990 	}
1991 
1992 	if (child->devclass)
1993 		devclass_delete_device(child->devclass, child);
1994 	if (child->parent)
1995 		BUS_CHILD_DELETED(dev, child);
1996 	TAILQ_REMOVE(&dev->children, child, link);
1997 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1998 	kobj_delete((kobj_t) child, M_BUS);
1999 
2000 	bus_data_generation_update();
2001 	return (0);
2002 }
2003 
2004 /**
2005  * @brief Delete all children devices of the given device, if any.
2006  *
2007  * This function deletes all children devices of the given device, if
2008  * any, using the device_delete_child() function for each device it
2009  * finds. If a child device cannot be deleted, this function will
2010  * return an error code.
2011  *
2012  * @param dev		the parent device
2013  *
2014  * @retval 0		success
2015  * @retval non-zero	a device would not detach
2016  */
2017 int
2018 device_delete_children(device_t dev)
2019 {
2020 	device_t child;
2021 	int error;
2022 
2023 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2024 
2025 	error = 0;
2026 
2027 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2028 		error = device_delete_child(dev, child);
2029 		if (error) {
2030 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2031 			break;
2032 		}
2033 	}
2034 	return (error);
2035 }
2036 
2037 /**
2038  * @brief Find a device given a unit number
2039  *
2040  * This is similar to devclass_get_devices() but only searches for
2041  * devices which have @p dev as a parent.
2042  *
2043  * @param dev		the parent device to search
2044  * @param unit		the unit number to search for.  If the unit is -1,
2045  *			return the first child of @p dev which has name
2046  *			@p classname (that is, the one with the lowest unit.)
2047  *
2048  * @returns		the device with the given unit number or @c
2049  *			NULL if there is no such device
2050  */
2051 device_t
2052 device_find_child(device_t dev, const char *classname, int unit)
2053 {
2054 	devclass_t dc;
2055 	device_t child;
2056 
2057 	dc = devclass_find(classname);
2058 	if (!dc)
2059 		return (NULL);
2060 
2061 	if (unit != -1) {
2062 		child = devclass_get_device(dc, unit);
2063 		if (child && child->parent == dev)
2064 			return (child);
2065 	} else {
2066 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2067 			child = devclass_get_device(dc, unit);
2068 			if (child && child->parent == dev)
2069 				return (child);
2070 		}
2071 	}
2072 	return (NULL);
2073 }
2074 
2075 /**
2076  * @internal
2077  */
2078 static driverlink_t
2079 first_matching_driver(devclass_t dc, device_t dev)
2080 {
2081 	if (dev->devclass)
2082 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2083 	return (TAILQ_FIRST(&dc->drivers));
2084 }
2085 
2086 /**
2087  * @internal
2088  */
2089 static driverlink_t
2090 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2091 {
2092 	if (dev->devclass) {
2093 		driverlink_t dl;
2094 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2095 			if (!strcmp(dev->devclass->name, dl->driver->name))
2096 				return (dl);
2097 		return (NULL);
2098 	}
2099 	return (TAILQ_NEXT(last, link));
2100 }
2101 
2102 /**
2103  * @internal
2104  */
2105 int
2106 device_probe_child(device_t dev, device_t child)
2107 {
2108 	devclass_t dc;
2109 	driverlink_t best = NULL;
2110 	driverlink_t dl;
2111 	int result, pri = 0;
2112 	/* We should preserve the devclass (or lack of) set by the bus. */
2113 	int hasclass = (child->devclass != NULL);
2114 
2115 	bus_topo_assert();
2116 
2117 	dc = dev->devclass;
2118 	if (!dc)
2119 		panic("device_probe_child: parent device has no devclass");
2120 
2121 	/*
2122 	 * If the state is already probed, then return.
2123 	 */
2124 	if (child->state == DS_ALIVE)
2125 		return (0);
2126 
2127 	for (; dc; dc = dc->parent) {
2128 		for (dl = first_matching_driver(dc, child);
2129 		     dl;
2130 		     dl = next_matching_driver(dc, child, dl)) {
2131 			/* If this driver's pass is too high, then ignore it. */
2132 			if (dl->pass > bus_current_pass)
2133 				continue;
2134 
2135 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2136 			result = device_set_driver(child, dl->driver);
2137 			if (result == ENOMEM)
2138 				return (result);
2139 			else if (result != 0)
2140 				continue;
2141 			if (!hasclass) {
2142 				if (device_set_devclass(child,
2143 				    dl->driver->name) != 0) {
2144 					char const * devname =
2145 					    device_get_name(child);
2146 					if (devname == NULL)
2147 						devname = "(unknown)";
2148 					printf("driver bug: Unable to set "
2149 					    "devclass (class: %s "
2150 					    "devname: %s)\n",
2151 					    dl->driver->name,
2152 					    devname);
2153 					(void)device_set_driver(child, NULL);
2154 					continue;
2155 				}
2156 			}
2157 
2158 			/* Fetch any flags for the device before probing. */
2159 			resource_int_value(dl->driver->name, child->unit,
2160 			    "flags", &child->devflags);
2161 
2162 			result = DEVICE_PROBE(child);
2163 
2164 			/*
2165 			 * If the driver returns SUCCESS, there can be
2166 			 * no higher match for this device.
2167 			 */
2168 			if (result == 0) {
2169 				best = dl;
2170 				pri = 0;
2171 				break;
2172 			}
2173 
2174 			/* Reset flags and devclass before the next probe. */
2175 			child->devflags = 0;
2176 			if (!hasclass)
2177 				(void)device_set_devclass(child, NULL);
2178 
2179 			/*
2180 			 * Reset DF_QUIET in case this driver doesn't
2181 			 * end up as the best driver.
2182 			 */
2183 			device_verbose(child);
2184 
2185 			/*
2186 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2187 			 * only match on devices whose driver was explicitly
2188 			 * specified.
2189 			 */
2190 			if (result <= BUS_PROBE_NOWILDCARD &&
2191 			    !(child->flags & DF_FIXEDCLASS)) {
2192 				result = ENXIO;
2193 			}
2194 
2195 			/*
2196 			 * The driver returned an error so it
2197 			 * certainly doesn't match.
2198 			 */
2199 			if (result > 0) {
2200 				(void)device_set_driver(child, NULL);
2201 				continue;
2202 			}
2203 
2204 			/*
2205 			 * A priority lower than SUCCESS, remember the
2206 			 * best matching driver. Initialise the value
2207 			 * of pri for the first match.
2208 			 */
2209 			if (best == NULL || result > pri) {
2210 				best = dl;
2211 				pri = result;
2212 				continue;
2213 			}
2214 		}
2215 		/*
2216 		 * If we have an unambiguous match in this devclass,
2217 		 * don't look in the parent.
2218 		 */
2219 		if (best && pri == 0)
2220 			break;
2221 	}
2222 
2223 	if (best == NULL)
2224 		return (ENXIO);
2225 
2226 	/*
2227 	 * If we found a driver, change state and initialise the devclass.
2228 	 */
2229 	if (pri < 0) {
2230 		/* Set the winning driver, devclass, and flags. */
2231 		result = device_set_driver(child, best->driver);
2232 		if (result != 0)
2233 			return (result);
2234 		if (!child->devclass) {
2235 			result = device_set_devclass(child, best->driver->name);
2236 			if (result != 0) {
2237 				(void)device_set_driver(child, NULL);
2238 				return (result);
2239 			}
2240 		}
2241 		resource_int_value(best->driver->name, child->unit,
2242 		    "flags", &child->devflags);
2243 
2244 		/*
2245 		 * A bit bogus. Call the probe method again to make sure
2246 		 * that we have the right description.
2247 		 */
2248 		result = DEVICE_PROBE(child);
2249 		if (result > 0) {
2250 			if (!hasclass)
2251 				(void)device_set_devclass(child, NULL);
2252 			(void)device_set_driver(child, NULL);
2253 			return (result);
2254 		}
2255 	}
2256 
2257 	child->state = DS_ALIVE;
2258 	bus_data_generation_update();
2259 	return (0);
2260 }
2261 
2262 /**
2263  * @brief Return the parent of a device
2264  */
2265 device_t
2266 device_get_parent(device_t dev)
2267 {
2268 	return (dev->parent);
2269 }
2270 
2271 /**
2272  * @brief Get a list of children of a device
2273  *
2274  * An array containing a list of all the children of the given device
2275  * is allocated and returned in @p *devlistp. The number of devices
2276  * in the array is returned in @p *devcountp. The caller should free
2277  * the array using @c free(p, M_TEMP).
2278  *
2279  * @param dev		the device to examine
2280  * @param devlistp	points at location for array pointer return
2281  *			value
2282  * @param devcountp	points at location for array size return value
2283  *
2284  * @retval 0		success
2285  * @retval ENOMEM	the array allocation failed
2286  */
2287 int
2288 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2289 {
2290 	int count;
2291 	device_t child;
2292 	device_t *list;
2293 
2294 	count = 0;
2295 	TAILQ_FOREACH(child, &dev->children, link) {
2296 		count++;
2297 	}
2298 	if (count == 0) {
2299 		*devlistp = NULL;
2300 		*devcountp = 0;
2301 		return (0);
2302 	}
2303 
2304 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2305 	if (!list)
2306 		return (ENOMEM);
2307 
2308 	count = 0;
2309 	TAILQ_FOREACH(child, &dev->children, link) {
2310 		list[count] = child;
2311 		count++;
2312 	}
2313 
2314 	*devlistp = list;
2315 	*devcountp = count;
2316 
2317 	return (0);
2318 }
2319 
2320 /**
2321  * @brief Return the current driver for the device or @c NULL if there
2322  * is no driver currently attached
2323  */
2324 driver_t *
2325 device_get_driver(device_t dev)
2326 {
2327 	return (dev->driver);
2328 }
2329 
2330 /**
2331  * @brief Return the current devclass for the device or @c NULL if
2332  * there is none.
2333  */
2334 devclass_t
2335 device_get_devclass(device_t dev)
2336 {
2337 	return (dev->devclass);
2338 }
2339 
2340 /**
2341  * @brief Return the name of the device's devclass or @c NULL if there
2342  * is none.
2343  */
2344 const char *
2345 device_get_name(device_t dev)
2346 {
2347 	if (dev != NULL && dev->devclass)
2348 		return (devclass_get_name(dev->devclass));
2349 	return (NULL);
2350 }
2351 
2352 /**
2353  * @brief Return a string containing the device's devclass name
2354  * followed by an ascii representation of the device's unit number
2355  * (e.g. @c "foo2").
2356  */
2357 const char *
2358 device_get_nameunit(device_t dev)
2359 {
2360 	return (dev->nameunit);
2361 }
2362 
2363 /**
2364  * @brief Return the device's unit number.
2365  */
2366 int
2367 device_get_unit(device_t dev)
2368 {
2369 	return (dev->unit);
2370 }
2371 
2372 /**
2373  * @brief Return the device's description string
2374  */
2375 const char *
2376 device_get_desc(device_t dev)
2377 {
2378 	return (dev->desc);
2379 }
2380 
2381 /**
2382  * @brief Return the device's flags
2383  */
2384 uint32_t
2385 device_get_flags(device_t dev)
2386 {
2387 	return (dev->devflags);
2388 }
2389 
2390 struct sysctl_ctx_list *
2391 device_get_sysctl_ctx(device_t dev)
2392 {
2393 	return (&dev->sysctl_ctx);
2394 }
2395 
2396 struct sysctl_oid *
2397 device_get_sysctl_tree(device_t dev)
2398 {
2399 	return (dev->sysctl_tree);
2400 }
2401 
2402 /**
2403  * @brief Print the name of the device followed by a colon and a space
2404  *
2405  * @returns the number of characters printed
2406  */
2407 int
2408 device_print_prettyname(device_t dev)
2409 {
2410 	const char *name = device_get_name(dev);
2411 
2412 	if (name == NULL)
2413 		return (printf("unknown: "));
2414 	return (printf("%s%d: ", name, device_get_unit(dev)));
2415 }
2416 
2417 /**
2418  * @brief Print the name of the device followed by a colon, a space
2419  * and the result of calling vprintf() with the value of @p fmt and
2420  * the following arguments.
2421  *
2422  * @returns the number of characters printed
2423  */
2424 int
2425 device_printf(device_t dev, const char * fmt, ...)
2426 {
2427 	char buf[128];
2428 	struct sbuf sb;
2429 	const char *name;
2430 	va_list ap;
2431 	size_t retval;
2432 
2433 	retval = 0;
2434 
2435 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2436 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2437 
2438 	name = device_get_name(dev);
2439 
2440 	if (name == NULL)
2441 		sbuf_cat(&sb, "unknown: ");
2442 	else
2443 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2444 
2445 	va_start(ap, fmt);
2446 	sbuf_vprintf(&sb, fmt, ap);
2447 	va_end(ap);
2448 
2449 	sbuf_finish(&sb);
2450 	sbuf_delete(&sb);
2451 
2452 	return (retval);
2453 }
2454 
2455 /**
2456  * @brief Print the name of the device followed by a colon, a space
2457  * and the result of calling log() with the value of @p fmt and
2458  * the following arguments.
2459  *
2460  * @returns the number of characters printed
2461  */
2462 int
2463 device_log(device_t dev, int pri, const char * fmt, ...)
2464 {
2465 	char buf[128];
2466 	struct sbuf sb;
2467 	const char *name;
2468 	va_list ap;
2469 	size_t retval;
2470 
2471 	retval = 0;
2472 
2473 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2474 
2475 	name = device_get_name(dev);
2476 
2477 	if (name == NULL)
2478 		sbuf_cat(&sb, "unknown: ");
2479 	else
2480 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2481 
2482 	va_start(ap, fmt);
2483 	sbuf_vprintf(&sb, fmt, ap);
2484 	va_end(ap);
2485 
2486 	sbuf_finish(&sb);
2487 
2488 	log(pri, "%.*s", (int) sbuf_len(&sb), sbuf_data(&sb));
2489 	retval = sbuf_len(&sb);
2490 
2491 	sbuf_delete(&sb);
2492 
2493 	return (retval);
2494 }
2495 
2496 /**
2497  * @internal
2498  */
2499 static void
2500 device_set_desc_internal(device_t dev, const char* desc, int copy)
2501 {
2502 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2503 		free(dev->desc, M_BUS);
2504 		dev->flags &= ~DF_DESCMALLOCED;
2505 		dev->desc = NULL;
2506 	}
2507 
2508 	if (copy && desc) {
2509 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2510 		if (dev->desc) {
2511 			strcpy(dev->desc, desc);
2512 			dev->flags |= DF_DESCMALLOCED;
2513 		}
2514 	} else {
2515 		/* Avoid a -Wcast-qual warning */
2516 		dev->desc = (char *)(uintptr_t) desc;
2517 	}
2518 
2519 	bus_data_generation_update();
2520 }
2521 
2522 /**
2523  * @brief Set the device's description
2524  *
2525  * The value of @c desc should be a string constant that will not
2526  * change (at least until the description is changed in a subsequent
2527  * call to device_set_desc() or device_set_desc_copy()).
2528  */
2529 void
2530 device_set_desc(device_t dev, const char* desc)
2531 {
2532 	device_set_desc_internal(dev, desc, FALSE);
2533 }
2534 
2535 /**
2536  * @brief Set the device's description
2537  *
2538  * The string pointed to by @c desc is copied. Use this function if
2539  * the device description is generated, (e.g. with sprintf()).
2540  */
2541 void
2542 device_set_desc_copy(device_t dev, const char* desc)
2543 {
2544 	device_set_desc_internal(dev, desc, TRUE);
2545 }
2546 
2547 /**
2548  * @brief Set the device's flags
2549  */
2550 void
2551 device_set_flags(device_t dev, uint32_t flags)
2552 {
2553 	dev->devflags = flags;
2554 }
2555 
2556 /**
2557  * @brief Return the device's softc field
2558  *
2559  * The softc is allocated and zeroed when a driver is attached, based
2560  * on the size field of the driver.
2561  */
2562 void *
2563 device_get_softc(device_t dev)
2564 {
2565 	return (dev->softc);
2566 }
2567 
2568 /**
2569  * @brief Set the device's softc field
2570  *
2571  * Most drivers do not need to use this since the softc is allocated
2572  * automatically when the driver is attached.
2573  */
2574 void
2575 device_set_softc(device_t dev, void *softc)
2576 {
2577 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2578 		free(dev->softc, M_BUS_SC);
2579 	dev->softc = softc;
2580 	if (dev->softc)
2581 		dev->flags |= DF_EXTERNALSOFTC;
2582 	else
2583 		dev->flags &= ~DF_EXTERNALSOFTC;
2584 }
2585 
2586 /**
2587  * @brief Free claimed softc
2588  *
2589  * Most drivers do not need to use this since the softc is freed
2590  * automatically when the driver is detached.
2591  */
2592 void
2593 device_free_softc(void *softc)
2594 {
2595 	free(softc, M_BUS_SC);
2596 }
2597 
2598 /**
2599  * @brief Claim softc
2600  *
2601  * This function can be used to let the driver free the automatically
2602  * allocated softc using "device_free_softc()". This function is
2603  * useful when the driver is refcounting the softc and the softc
2604  * cannot be freed when the "device_detach" method is called.
2605  */
2606 void
2607 device_claim_softc(device_t dev)
2608 {
2609 	if (dev->softc)
2610 		dev->flags |= DF_EXTERNALSOFTC;
2611 	else
2612 		dev->flags &= ~DF_EXTERNALSOFTC;
2613 }
2614 
2615 /**
2616  * @brief Get the device's ivars field
2617  *
2618  * The ivars field is used by the parent device to store per-device
2619  * state (e.g. the physical location of the device or a list of
2620  * resources).
2621  */
2622 void *
2623 device_get_ivars(device_t dev)
2624 {
2625 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2626 	return (dev->ivars);
2627 }
2628 
2629 /**
2630  * @brief Set the device's ivars field
2631  */
2632 void
2633 device_set_ivars(device_t dev, void * ivars)
2634 {
2635 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2636 	dev->ivars = ivars;
2637 }
2638 
2639 /**
2640  * @brief Return the device's state
2641  */
2642 device_state_t
2643 device_get_state(device_t dev)
2644 {
2645 	return (dev->state);
2646 }
2647 
2648 /**
2649  * @brief Set the DF_ENABLED flag for the device
2650  */
2651 void
2652 device_enable(device_t dev)
2653 {
2654 	dev->flags |= DF_ENABLED;
2655 }
2656 
2657 /**
2658  * @brief Clear the DF_ENABLED flag for the device
2659  */
2660 void
2661 device_disable(device_t dev)
2662 {
2663 	dev->flags &= ~DF_ENABLED;
2664 }
2665 
2666 /**
2667  * @brief Increment the busy counter for the device
2668  */
2669 void
2670 device_busy(device_t dev)
2671 {
2672 
2673 	/*
2674 	 * Mark the device as busy, recursively up the tree if this busy count
2675 	 * goes 0->1.
2676 	 */
2677 	if (refcount_acquire(&dev->busy) == 0 && dev->parent != NULL)
2678 		device_busy(dev->parent);
2679 }
2680 
2681 /**
2682  * @brief Decrement the busy counter for the device
2683  */
2684 void
2685 device_unbusy(device_t dev)
2686 {
2687 
2688 	/*
2689 	 * Mark the device as unbsy, recursively if this is the last busy count.
2690 	 */
2691 	if (refcount_release(&dev->busy) && dev->parent != NULL)
2692 		device_unbusy(dev->parent);
2693 }
2694 
2695 /**
2696  * @brief Set the DF_QUIET flag for the device
2697  */
2698 void
2699 device_quiet(device_t dev)
2700 {
2701 	dev->flags |= DF_QUIET;
2702 }
2703 
2704 /**
2705  * @brief Set the DF_QUIET_CHILDREN flag for the device
2706  */
2707 void
2708 device_quiet_children(device_t dev)
2709 {
2710 	dev->flags |= DF_QUIET_CHILDREN;
2711 }
2712 
2713 /**
2714  * @brief Clear the DF_QUIET flag for the device
2715  */
2716 void
2717 device_verbose(device_t dev)
2718 {
2719 	dev->flags &= ~DF_QUIET;
2720 }
2721 
2722 ssize_t
2723 device_get_property(device_t dev, const char *prop, void *val, size_t sz,
2724     device_property_type_t type)
2725 {
2726 	device_t bus = device_get_parent(dev);
2727 
2728 	switch (type) {
2729 	case DEVICE_PROP_ANY:
2730 	case DEVICE_PROP_BUFFER:
2731 		break;
2732 	case DEVICE_PROP_UINT32:
2733 		if (sz % 4 != 0)
2734 			return (-1);
2735 		break;
2736 	case DEVICE_PROP_UINT64:
2737 		if (sz % 8 != 0)
2738 			return (-1);
2739 		break;
2740 	default:
2741 		return (-1);
2742 	}
2743 
2744 	return (BUS_GET_PROPERTY(bus, dev, prop, val, sz, type));
2745 }
2746 
2747 bool
2748 device_has_property(device_t dev, const char *prop)
2749 {
2750 	return (device_get_property(dev, prop, NULL, 0, DEVICE_PROP_ANY) >= 0);
2751 }
2752 
2753 /**
2754  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2755  */
2756 int
2757 device_has_quiet_children(device_t dev)
2758 {
2759 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2760 }
2761 
2762 /**
2763  * @brief Return non-zero if the DF_QUIET flag is set on the device
2764  */
2765 int
2766 device_is_quiet(device_t dev)
2767 {
2768 	return ((dev->flags & DF_QUIET) != 0);
2769 }
2770 
2771 /**
2772  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2773  */
2774 int
2775 device_is_enabled(device_t dev)
2776 {
2777 	return ((dev->flags & DF_ENABLED) != 0);
2778 }
2779 
2780 /**
2781  * @brief Return non-zero if the device was successfully probed
2782  */
2783 int
2784 device_is_alive(device_t dev)
2785 {
2786 	return (dev->state >= DS_ALIVE);
2787 }
2788 
2789 /**
2790  * @brief Return non-zero if the device currently has a driver
2791  * attached to it
2792  */
2793 int
2794 device_is_attached(device_t dev)
2795 {
2796 	return (dev->state >= DS_ATTACHED);
2797 }
2798 
2799 /**
2800  * @brief Return non-zero if the device is currently suspended.
2801  */
2802 int
2803 device_is_suspended(device_t dev)
2804 {
2805 	return ((dev->flags & DF_SUSPENDED) != 0);
2806 }
2807 
2808 /**
2809  * @brief Set the devclass of a device
2810  * @see devclass_add_device().
2811  */
2812 int
2813 device_set_devclass(device_t dev, const char *classname)
2814 {
2815 	devclass_t dc;
2816 	int error;
2817 
2818 	if (!classname) {
2819 		if (dev->devclass)
2820 			devclass_delete_device(dev->devclass, dev);
2821 		return (0);
2822 	}
2823 
2824 	if (dev->devclass) {
2825 		printf("device_set_devclass: device class already set\n");
2826 		return (EINVAL);
2827 	}
2828 
2829 	dc = devclass_find_internal(classname, NULL, TRUE);
2830 	if (!dc)
2831 		return (ENOMEM);
2832 
2833 	error = devclass_add_device(dc, dev);
2834 
2835 	bus_data_generation_update();
2836 	return (error);
2837 }
2838 
2839 /**
2840  * @brief Set the devclass of a device and mark the devclass fixed.
2841  * @see device_set_devclass()
2842  */
2843 int
2844 device_set_devclass_fixed(device_t dev, const char *classname)
2845 {
2846 	int error;
2847 
2848 	if (classname == NULL)
2849 		return (EINVAL);
2850 
2851 	error = device_set_devclass(dev, classname);
2852 	if (error)
2853 		return (error);
2854 	dev->flags |= DF_FIXEDCLASS;
2855 	return (0);
2856 }
2857 
2858 /**
2859  * @brief Query the device to determine if it's of a fixed devclass
2860  * @see device_set_devclass_fixed()
2861  */
2862 bool
2863 device_is_devclass_fixed(device_t dev)
2864 {
2865 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2866 }
2867 
2868 /**
2869  * @brief Set the driver of a device
2870  *
2871  * @retval 0		success
2872  * @retval EBUSY	the device already has a driver attached
2873  * @retval ENOMEM	a memory allocation failure occurred
2874  */
2875 int
2876 device_set_driver(device_t dev, driver_t *driver)
2877 {
2878 	int domain;
2879 	struct domainset *policy;
2880 
2881 	if (dev->state >= DS_ATTACHED)
2882 		return (EBUSY);
2883 
2884 	if (dev->driver == driver)
2885 		return (0);
2886 
2887 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2888 		free(dev->softc, M_BUS_SC);
2889 		dev->softc = NULL;
2890 	}
2891 	device_set_desc(dev, NULL);
2892 	kobj_delete((kobj_t) dev, NULL);
2893 	dev->driver = driver;
2894 	if (driver) {
2895 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2896 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2897 			if (bus_get_domain(dev, &domain) == 0)
2898 				policy = DOMAINSET_PREF(domain);
2899 			else
2900 				policy = DOMAINSET_RR();
2901 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2902 			    policy, M_NOWAIT | M_ZERO);
2903 			if (!dev->softc) {
2904 				kobj_delete((kobj_t) dev, NULL);
2905 				kobj_init((kobj_t) dev, &null_class);
2906 				dev->driver = NULL;
2907 				return (ENOMEM);
2908 			}
2909 		}
2910 	} else {
2911 		kobj_init((kobj_t) dev, &null_class);
2912 	}
2913 
2914 	bus_data_generation_update();
2915 	return (0);
2916 }
2917 
2918 /**
2919  * @brief Probe a device, and return this status.
2920  *
2921  * This function is the core of the device autoconfiguration
2922  * system. Its purpose is to select a suitable driver for a device and
2923  * then call that driver to initialise the hardware appropriately. The
2924  * driver is selected by calling the DEVICE_PROBE() method of a set of
2925  * candidate drivers and then choosing the driver which returned the
2926  * best value. This driver is then attached to the device using
2927  * device_attach().
2928  *
2929  * The set of suitable drivers is taken from the list of drivers in
2930  * the parent device's devclass. If the device was originally created
2931  * with a specific class name (see device_add_child()), only drivers
2932  * with that name are probed, otherwise all drivers in the devclass
2933  * are probed. If no drivers return successful probe values in the
2934  * parent devclass, the search continues in the parent of that
2935  * devclass (see devclass_get_parent()) if any.
2936  *
2937  * @param dev		the device to initialise
2938  *
2939  * @retval 0		success
2940  * @retval ENXIO	no driver was found
2941  * @retval ENOMEM	memory allocation failure
2942  * @retval non-zero	some other unix error code
2943  * @retval -1		Device already attached
2944  */
2945 int
2946 device_probe(device_t dev)
2947 {
2948 	int error;
2949 
2950 	bus_topo_assert();
2951 
2952 	if (dev->state >= DS_ALIVE)
2953 		return (-1);
2954 
2955 	if (!(dev->flags & DF_ENABLED)) {
2956 		if (bootverbose && device_get_name(dev) != NULL) {
2957 			device_print_prettyname(dev);
2958 			printf("not probed (disabled)\n");
2959 		}
2960 		return (-1);
2961 	}
2962 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2963 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2964 		    !(dev->flags & DF_DONENOMATCH)) {
2965 			BUS_PROBE_NOMATCH(dev->parent, dev);
2966 			devnomatch(dev);
2967 			dev->flags |= DF_DONENOMATCH;
2968 		}
2969 		return (error);
2970 	}
2971 	return (0);
2972 }
2973 
2974 /**
2975  * @brief Probe a device and attach a driver if possible
2976  *
2977  * calls device_probe() and attaches if that was successful.
2978  */
2979 int
2980 device_probe_and_attach(device_t dev)
2981 {
2982 	int error;
2983 
2984 	bus_topo_assert();
2985 
2986 	error = device_probe(dev);
2987 	if (error == -1)
2988 		return (0);
2989 	else if (error != 0)
2990 		return (error);
2991 
2992 	CURVNET_SET_QUIET(vnet0);
2993 	error = device_attach(dev);
2994 	CURVNET_RESTORE();
2995 	return error;
2996 }
2997 
2998 /**
2999  * @brief Attach a device driver to a device
3000  *
3001  * This function is a wrapper around the DEVICE_ATTACH() driver
3002  * method. In addition to calling DEVICE_ATTACH(), it initialises the
3003  * device's sysctl tree, optionally prints a description of the device
3004  * and queues a notification event for user-based device management
3005  * services.
3006  *
3007  * Normally this function is only called internally from
3008  * device_probe_and_attach().
3009  *
3010  * @param dev		the device to initialise
3011  *
3012  * @retval 0		success
3013  * @retval ENXIO	no driver was found
3014  * @retval ENOMEM	memory allocation failure
3015  * @retval non-zero	some other unix error code
3016  */
3017 int
3018 device_attach(device_t dev)
3019 {
3020 	uint64_t attachtime;
3021 	uint16_t attachentropy;
3022 	int error;
3023 
3024 	if (resource_disabled(dev->driver->name, dev->unit)) {
3025 		device_disable(dev);
3026 		if (bootverbose)
3027 			 device_printf(dev, "disabled via hints entry\n");
3028 		return (ENXIO);
3029 	}
3030 
3031 	device_sysctl_init(dev);
3032 	if (!device_is_quiet(dev))
3033 		device_print_child(dev->parent, dev);
3034 	attachtime = get_cyclecount();
3035 	dev->state = DS_ATTACHING;
3036 	if ((error = DEVICE_ATTACH(dev)) != 0) {
3037 		printf("device_attach: %s%d attach returned %d\n",
3038 		    dev->driver->name, dev->unit, error);
3039 		if (!(dev->flags & DF_FIXEDCLASS))
3040 			devclass_delete_device(dev->devclass, dev);
3041 		(void)device_set_driver(dev, NULL);
3042 		device_sysctl_fini(dev);
3043 		KASSERT(dev->busy == 0, ("attach failed but busy"));
3044 		dev->state = DS_NOTPRESENT;
3045 		return (error);
3046 	}
3047 	dev->flags |= DF_ATTACHED_ONCE;
3048 	/* We only need the low bits of this time, but ranges from tens to thousands
3049 	 * have been seen, so keep 2 bytes' worth.
3050 	 */
3051 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3052 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3053 	device_sysctl_update(dev);
3054 	dev->state = DS_ATTACHED;
3055 	dev->flags &= ~DF_DONENOMATCH;
3056 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3057 	devadded(dev);
3058 	return (0);
3059 }
3060 
3061 /**
3062  * @brief Detach a driver from a device
3063  *
3064  * This function is a wrapper around the DEVICE_DETACH() driver
3065  * method. If the call to DEVICE_DETACH() succeeds, it calls
3066  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3067  * notification event for user-based device management services and
3068  * cleans up the device's sysctl tree.
3069  *
3070  * @param dev		the device to un-initialise
3071  *
3072  * @retval 0		success
3073  * @retval ENXIO	no driver was found
3074  * @retval ENOMEM	memory allocation failure
3075  * @retval non-zero	some other unix error code
3076  */
3077 int
3078 device_detach(device_t dev)
3079 {
3080 	int error;
3081 
3082 	bus_topo_assert();
3083 
3084 	PDEBUG(("%s", DEVICENAME(dev)));
3085 	if (dev->busy > 0)
3086 		return (EBUSY);
3087 	if (dev->state == DS_ATTACHING) {
3088 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3089 		return (EBUSY);
3090 	}
3091 	if (dev->state != DS_ATTACHED)
3092 		return (0);
3093 
3094 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3095 	if ((error = DEVICE_DETACH(dev)) != 0) {
3096 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3097 		    EVHDEV_DETACH_FAILED);
3098 		return (error);
3099 	} else {
3100 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3101 		    EVHDEV_DETACH_COMPLETE);
3102 	}
3103 	devremoved(dev);
3104 	if (!device_is_quiet(dev))
3105 		device_printf(dev, "detached\n");
3106 	if (dev->parent)
3107 		BUS_CHILD_DETACHED(dev->parent, dev);
3108 
3109 	if (!(dev->flags & DF_FIXEDCLASS))
3110 		devclass_delete_device(dev->devclass, dev);
3111 
3112 	device_verbose(dev);
3113 	dev->state = DS_NOTPRESENT;
3114 	(void)device_set_driver(dev, NULL);
3115 	device_sysctl_fini(dev);
3116 
3117 	return (0);
3118 }
3119 
3120 /**
3121  * @brief Tells a driver to quiesce itself.
3122  *
3123  * This function is a wrapper around the DEVICE_QUIESCE() driver
3124  * method. If the call to DEVICE_QUIESCE() succeeds.
3125  *
3126  * @param dev		the device to quiesce
3127  *
3128  * @retval 0		success
3129  * @retval ENXIO	no driver was found
3130  * @retval ENOMEM	memory allocation failure
3131  * @retval non-zero	some other unix error code
3132  */
3133 int
3134 device_quiesce(device_t dev)
3135 {
3136 	PDEBUG(("%s", DEVICENAME(dev)));
3137 	if (dev->busy > 0)
3138 		return (EBUSY);
3139 	if (dev->state != DS_ATTACHED)
3140 		return (0);
3141 
3142 	return (DEVICE_QUIESCE(dev));
3143 }
3144 
3145 /**
3146  * @brief Notify a device of system shutdown
3147  *
3148  * This function calls the DEVICE_SHUTDOWN() driver method if the
3149  * device currently has an attached driver.
3150  *
3151  * @returns the value returned by DEVICE_SHUTDOWN()
3152  */
3153 int
3154 device_shutdown(device_t dev)
3155 {
3156 	if (dev->state < DS_ATTACHED)
3157 		return (0);
3158 	return (DEVICE_SHUTDOWN(dev));
3159 }
3160 
3161 /**
3162  * @brief Set the unit number of a device
3163  *
3164  * This function can be used to override the unit number used for a
3165  * device (e.g. to wire a device to a pre-configured unit number).
3166  */
3167 int
3168 device_set_unit(device_t dev, int unit)
3169 {
3170 	devclass_t dc;
3171 	int err;
3172 
3173 	if (unit == dev->unit)
3174 		return (0);
3175 	dc = device_get_devclass(dev);
3176 	if (unit < dc->maxunit && dc->devices[unit])
3177 		return (EBUSY);
3178 	err = devclass_delete_device(dc, dev);
3179 	if (err)
3180 		return (err);
3181 	dev->unit = unit;
3182 	err = devclass_add_device(dc, dev);
3183 	if (err)
3184 		return (err);
3185 
3186 	bus_data_generation_update();
3187 	return (0);
3188 }
3189 
3190 /*======================================*/
3191 /*
3192  * Some useful method implementations to make life easier for bus drivers.
3193  */
3194 
3195 void
3196 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3197 {
3198 	bzero(args, sz);
3199 	args->size = sz;
3200 	args->memattr = VM_MEMATTR_DEVICE;
3201 }
3202 
3203 /**
3204  * @brief Initialise a resource list.
3205  *
3206  * @param rl		the resource list to initialise
3207  */
3208 void
3209 resource_list_init(struct resource_list *rl)
3210 {
3211 	STAILQ_INIT(rl);
3212 }
3213 
3214 /**
3215  * @brief Reclaim memory used by a resource list.
3216  *
3217  * This function frees the memory for all resource entries on the list
3218  * (if any).
3219  *
3220  * @param rl		the resource list to free
3221  */
3222 void
3223 resource_list_free(struct resource_list *rl)
3224 {
3225 	struct resource_list_entry *rle;
3226 
3227 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3228 		if (rle->res)
3229 			panic("resource_list_free: resource entry is busy");
3230 		STAILQ_REMOVE_HEAD(rl, link);
3231 		free(rle, M_BUS);
3232 	}
3233 }
3234 
3235 /**
3236  * @brief Add a resource entry.
3237  *
3238  * This function adds a resource entry using the given @p type, @p
3239  * start, @p end and @p count values. A rid value is chosen by
3240  * searching sequentially for the first unused rid starting at zero.
3241  *
3242  * @param rl		the resource list to edit
3243  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3244  * @param start		the start address of the resource
3245  * @param end		the end address of the resource
3246  * @param count		XXX end-start+1
3247  */
3248 int
3249 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3250     rman_res_t end, rman_res_t count)
3251 {
3252 	int rid;
3253 
3254 	rid = 0;
3255 	while (resource_list_find(rl, type, rid) != NULL)
3256 		rid++;
3257 	resource_list_add(rl, type, rid, start, end, count);
3258 	return (rid);
3259 }
3260 
3261 /**
3262  * @brief Add or modify a resource entry.
3263  *
3264  * If an existing entry exists with the same type and rid, it will be
3265  * modified using the given values of @p start, @p end and @p
3266  * count. If no entry exists, a new one will be created using the
3267  * given values.  The resource list entry that matches is then returned.
3268  *
3269  * @param rl		the resource list to edit
3270  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3271  * @param rid		the resource identifier
3272  * @param start		the start address of the resource
3273  * @param end		the end address of the resource
3274  * @param count		XXX end-start+1
3275  */
3276 struct resource_list_entry *
3277 resource_list_add(struct resource_list *rl, int type, int rid,
3278     rman_res_t start, rman_res_t end, rman_res_t count)
3279 {
3280 	struct resource_list_entry *rle;
3281 
3282 	rle = resource_list_find(rl, type, rid);
3283 	if (!rle) {
3284 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3285 		    M_NOWAIT);
3286 		if (!rle)
3287 			panic("resource_list_add: can't record entry");
3288 		STAILQ_INSERT_TAIL(rl, rle, link);
3289 		rle->type = type;
3290 		rle->rid = rid;
3291 		rle->res = NULL;
3292 		rle->flags = 0;
3293 	}
3294 
3295 	if (rle->res)
3296 		panic("resource_list_add: resource entry is busy");
3297 
3298 	rle->start = start;
3299 	rle->end = end;
3300 	rle->count = count;
3301 	return (rle);
3302 }
3303 
3304 /**
3305  * @brief Determine if a resource entry is busy.
3306  *
3307  * Returns true if a resource entry is busy meaning that it has an
3308  * associated resource that is not an unallocated "reserved" resource.
3309  *
3310  * @param rl		the resource list to search
3311  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3312  * @param rid		the resource identifier
3313  *
3314  * @returns Non-zero if the entry is busy, zero otherwise.
3315  */
3316 int
3317 resource_list_busy(struct resource_list *rl, int type, int rid)
3318 {
3319 	struct resource_list_entry *rle;
3320 
3321 	rle = resource_list_find(rl, type, rid);
3322 	if (rle == NULL || rle->res == NULL)
3323 		return (0);
3324 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3325 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3326 		    ("reserved resource is active"));
3327 		return (0);
3328 	}
3329 	return (1);
3330 }
3331 
3332 /**
3333  * @brief Determine if a resource entry is reserved.
3334  *
3335  * Returns true if a resource entry is reserved meaning that it has an
3336  * associated "reserved" resource.  The resource can either be
3337  * allocated or unallocated.
3338  *
3339  * @param rl		the resource list to search
3340  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3341  * @param rid		the resource identifier
3342  *
3343  * @returns Non-zero if the entry is reserved, zero otherwise.
3344  */
3345 int
3346 resource_list_reserved(struct resource_list *rl, int type, int rid)
3347 {
3348 	struct resource_list_entry *rle;
3349 
3350 	rle = resource_list_find(rl, type, rid);
3351 	if (rle != NULL && rle->flags & RLE_RESERVED)
3352 		return (1);
3353 	return (0);
3354 }
3355 
3356 /**
3357  * @brief Find a resource entry by type and rid.
3358  *
3359  * @param rl		the resource list to search
3360  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3361  * @param rid		the resource identifier
3362  *
3363  * @returns the resource entry pointer or NULL if there is no such
3364  * entry.
3365  */
3366 struct resource_list_entry *
3367 resource_list_find(struct resource_list *rl, int type, int rid)
3368 {
3369 	struct resource_list_entry *rle;
3370 
3371 	STAILQ_FOREACH(rle, rl, link) {
3372 		if (rle->type == type && rle->rid == rid)
3373 			return (rle);
3374 	}
3375 	return (NULL);
3376 }
3377 
3378 /**
3379  * @brief Delete a resource entry.
3380  *
3381  * @param rl		the resource list to edit
3382  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3383  * @param rid		the resource identifier
3384  */
3385 void
3386 resource_list_delete(struct resource_list *rl, int type, int rid)
3387 {
3388 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3389 
3390 	if (rle) {
3391 		if (rle->res != NULL)
3392 			panic("resource_list_delete: resource has not been released");
3393 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3394 		free(rle, M_BUS);
3395 	}
3396 }
3397 
3398 /**
3399  * @brief Allocate a reserved resource
3400  *
3401  * This can be used by buses to force the allocation of resources
3402  * that are always active in the system even if they are not allocated
3403  * by a driver (e.g. PCI BARs).  This function is usually called when
3404  * adding a new child to the bus.  The resource is allocated from the
3405  * parent bus when it is reserved.  The resource list entry is marked
3406  * with RLE_RESERVED to note that it is a reserved resource.
3407  *
3408  * Subsequent attempts to allocate the resource with
3409  * resource_list_alloc() will succeed the first time and will set
3410  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3411  * resource that has been allocated is released with
3412  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3413  * the actual resource remains allocated.  The resource can be released to
3414  * the parent bus by calling resource_list_unreserve().
3415  *
3416  * @param rl		the resource list to allocate from
3417  * @param bus		the parent device of @p child
3418  * @param child		the device for which the resource is being reserved
3419  * @param type		the type of resource to allocate
3420  * @param rid		a pointer to the resource identifier
3421  * @param start		hint at the start of the resource range - pass
3422  *			@c 0 for any start address
3423  * @param end		hint at the end of the resource range - pass
3424  *			@c ~0 for any end address
3425  * @param count		hint at the size of range required - pass @c 1
3426  *			for any size
3427  * @param flags		any extra flags to control the resource
3428  *			allocation - see @c RF_XXX flags in
3429  *			<sys/rman.h> for details
3430  *
3431  * @returns		the resource which was allocated or @c NULL if no
3432  *			resource could be allocated
3433  */
3434 struct resource *
3435 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3436     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3437 {
3438 	struct resource_list_entry *rle = NULL;
3439 	int passthrough = (device_get_parent(child) != bus);
3440 	struct resource *r;
3441 
3442 	if (passthrough)
3443 		panic(
3444     "resource_list_reserve() should only be called for direct children");
3445 	if (flags & RF_ACTIVE)
3446 		panic(
3447     "resource_list_reserve() should only reserve inactive resources");
3448 
3449 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3450 	    flags);
3451 	if (r != NULL) {
3452 		rle = resource_list_find(rl, type, *rid);
3453 		rle->flags |= RLE_RESERVED;
3454 	}
3455 	return (r);
3456 }
3457 
3458 /**
3459  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3460  *
3461  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3462  * and passing the allocation up to the parent of @p bus. This assumes
3463  * that the first entry of @c device_get_ivars(child) is a struct
3464  * resource_list. This also handles 'passthrough' allocations where a
3465  * child is a remote descendant of bus by passing the allocation up to
3466  * the parent of bus.
3467  *
3468  * Typically, a bus driver would store a list of child resources
3469  * somewhere in the child device's ivars (see device_get_ivars()) and
3470  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3471  * then call resource_list_alloc() to perform the allocation.
3472  *
3473  * @param rl		the resource list to allocate from
3474  * @param bus		the parent device of @p child
3475  * @param child		the device which is requesting an allocation
3476  * @param type		the type of resource to allocate
3477  * @param rid		a pointer to the resource identifier
3478  * @param start		hint at the start of the resource range - pass
3479  *			@c 0 for any start address
3480  * @param end		hint at the end of the resource range - pass
3481  *			@c ~0 for any end address
3482  * @param count		hint at the size of range required - pass @c 1
3483  *			for any size
3484  * @param flags		any extra flags to control the resource
3485  *			allocation - see @c RF_XXX flags in
3486  *			<sys/rman.h> for details
3487  *
3488  * @returns		the resource which was allocated or @c NULL if no
3489  *			resource could be allocated
3490  */
3491 struct resource *
3492 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3493     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3494 {
3495 	struct resource_list_entry *rle = NULL;
3496 	int passthrough = (device_get_parent(child) != bus);
3497 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3498 
3499 	if (passthrough) {
3500 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3501 		    type, rid, start, end, count, flags));
3502 	}
3503 
3504 	rle = resource_list_find(rl, type, *rid);
3505 
3506 	if (!rle)
3507 		return (NULL);		/* no resource of that type/rid */
3508 
3509 	if (rle->res) {
3510 		if (rle->flags & RLE_RESERVED) {
3511 			if (rle->flags & RLE_ALLOCATED)
3512 				return (NULL);
3513 			if ((flags & RF_ACTIVE) &&
3514 			    bus_activate_resource(child, type, *rid,
3515 			    rle->res) != 0)
3516 				return (NULL);
3517 			rle->flags |= RLE_ALLOCATED;
3518 			return (rle->res);
3519 		}
3520 		device_printf(bus,
3521 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3522 		    type, device_get_nameunit(child));
3523 		return (NULL);
3524 	}
3525 
3526 	if (isdefault) {
3527 		start = rle->start;
3528 		count = ulmax(count, rle->count);
3529 		end = ulmax(rle->end, start + count - 1);
3530 	}
3531 
3532 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3533 	    type, rid, start, end, count, flags);
3534 
3535 	/*
3536 	 * Record the new range.
3537 	 */
3538 	if (rle->res) {
3539 		rle->start = rman_get_start(rle->res);
3540 		rle->end = rman_get_end(rle->res);
3541 		rle->count = count;
3542 	}
3543 
3544 	return (rle->res);
3545 }
3546 
3547 /**
3548  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3549  *
3550  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3551  * used with resource_list_alloc().
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 which is requesting a release
3556  * @param type		the type of resource to release
3557  * @param rid		the resource identifier
3558  * @param res		the resource to release
3559  *
3560  * @retval 0		success
3561  * @retval non-zero	a standard unix error code indicating what
3562  *			error condition prevented the operation
3563  */
3564 int
3565 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3566     int type, int rid, struct resource *res)
3567 {
3568 	struct resource_list_entry *rle = NULL;
3569 	int passthrough = (device_get_parent(child) != bus);
3570 	int error;
3571 
3572 	if (passthrough) {
3573 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3574 		    type, rid, res));
3575 	}
3576 
3577 	rle = resource_list_find(rl, type, rid);
3578 
3579 	if (!rle)
3580 		panic("resource_list_release: can't find resource");
3581 	if (!rle->res)
3582 		panic("resource_list_release: resource entry is not busy");
3583 	if (rle->flags & RLE_RESERVED) {
3584 		if (rle->flags & RLE_ALLOCATED) {
3585 			if (rman_get_flags(res) & RF_ACTIVE) {
3586 				error = bus_deactivate_resource(child, type,
3587 				    rid, res);
3588 				if (error)
3589 					return (error);
3590 			}
3591 			rle->flags &= ~RLE_ALLOCATED;
3592 			return (0);
3593 		}
3594 		return (EINVAL);
3595 	}
3596 
3597 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3598 	    type, rid, res);
3599 	if (error)
3600 		return (error);
3601 
3602 	rle->res = NULL;
3603 	return (0);
3604 }
3605 
3606 /**
3607  * @brief Release all active resources of a given type
3608  *
3609  * Release all active resources of a specified type.  This is intended
3610  * to be used to cleanup resources leaked by a driver after detach or
3611  * a failed attach.
3612  *
3613  * @param rl		the resource list which was allocated from
3614  * @param bus		the parent device of @p child
3615  * @param child		the device whose active resources are being released
3616  * @param type		the type of resources to release
3617  *
3618  * @retval 0		success
3619  * @retval EBUSY	at least one resource was active
3620  */
3621 int
3622 resource_list_release_active(struct resource_list *rl, device_t bus,
3623     device_t child, int type)
3624 {
3625 	struct resource_list_entry *rle;
3626 	int error, retval;
3627 
3628 	retval = 0;
3629 	STAILQ_FOREACH(rle, rl, link) {
3630 		if (rle->type != type)
3631 			continue;
3632 		if (rle->res == NULL)
3633 			continue;
3634 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3635 		    RLE_RESERVED)
3636 			continue;
3637 		retval = EBUSY;
3638 		error = resource_list_release(rl, bus, child, type,
3639 		    rman_get_rid(rle->res), rle->res);
3640 		if (error != 0)
3641 			device_printf(bus,
3642 			    "Failed to release active resource: %d\n", error);
3643 	}
3644 	return (retval);
3645 }
3646 
3647 /**
3648  * @brief Fully release a reserved resource
3649  *
3650  * Fully releases a resource reserved via resource_list_reserve().
3651  *
3652  * @param rl		the resource list which was allocated from
3653  * @param bus		the parent device of @p child
3654  * @param child		the device whose reserved resource is being released
3655  * @param type		the type of resource to release
3656  * @param rid		the resource identifier
3657  * @param res		the resource to release
3658  *
3659  * @retval 0		success
3660  * @retval non-zero	a standard unix error code indicating what
3661  *			error condition prevented the operation
3662  */
3663 int
3664 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3665     int type, int rid)
3666 {
3667 	struct resource_list_entry *rle = NULL;
3668 	int passthrough = (device_get_parent(child) != bus);
3669 
3670 	if (passthrough)
3671 		panic(
3672     "resource_list_unreserve() should only be called for direct children");
3673 
3674 	rle = resource_list_find(rl, type, rid);
3675 
3676 	if (!rle)
3677 		panic("resource_list_unreserve: can't find resource");
3678 	if (!(rle->flags & RLE_RESERVED))
3679 		return (EINVAL);
3680 	if (rle->flags & RLE_ALLOCATED)
3681 		return (EBUSY);
3682 	rle->flags &= ~RLE_RESERVED;
3683 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3684 }
3685 
3686 /**
3687  * @brief Print a description of resources in a resource list
3688  *
3689  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3690  * The name is printed if at least one resource of the given type is available.
3691  * The format is used to print resource start and end.
3692  *
3693  * @param rl		the resource list to print
3694  * @param name		the name of @p type, e.g. @c "memory"
3695  * @param type		type type of resource entry to print
3696  * @param format	printf(9) format string to print resource
3697  *			start and end values
3698  *
3699  * @returns		the number of characters printed
3700  */
3701 int
3702 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3703     const char *format)
3704 {
3705 	struct resource_list_entry *rle;
3706 	int printed, retval;
3707 
3708 	printed = 0;
3709 	retval = 0;
3710 	/* Yes, this is kinda cheating */
3711 	STAILQ_FOREACH(rle, rl, link) {
3712 		if (rle->type == type) {
3713 			if (printed == 0)
3714 				retval += printf(" %s ", name);
3715 			else
3716 				retval += printf(",");
3717 			printed++;
3718 			retval += printf(format, rle->start);
3719 			if (rle->count > 1) {
3720 				retval += printf("-");
3721 				retval += printf(format, rle->start +
3722 						 rle->count - 1);
3723 			}
3724 		}
3725 	}
3726 	return (retval);
3727 }
3728 
3729 /**
3730  * @brief Releases all the resources in a list.
3731  *
3732  * @param rl		The resource list to purge.
3733  *
3734  * @returns		nothing
3735  */
3736 void
3737 resource_list_purge(struct resource_list *rl)
3738 {
3739 	struct resource_list_entry *rle;
3740 
3741 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3742 		if (rle->res)
3743 			bus_release_resource(rman_get_device(rle->res),
3744 			    rle->type, rle->rid, rle->res);
3745 		STAILQ_REMOVE_HEAD(rl, link);
3746 		free(rle, M_BUS);
3747 	}
3748 }
3749 
3750 device_t
3751 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3752 {
3753 	return (device_add_child_ordered(dev, order, name, unit));
3754 }
3755 
3756 /**
3757  * @brief Helper function for implementing DEVICE_PROBE()
3758  *
3759  * This function can be used to help implement the DEVICE_PROBE() for
3760  * a bus (i.e. a device which has other devices attached to it). It
3761  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3762  * devclass.
3763  */
3764 int
3765 bus_generic_probe(device_t dev)
3766 {
3767 	devclass_t dc = dev->devclass;
3768 	driverlink_t dl;
3769 
3770 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3771 		/*
3772 		 * If this driver's pass is too high, then ignore it.
3773 		 * For most drivers in the default pass, this will
3774 		 * never be true.  For early-pass drivers they will
3775 		 * only call the identify routines of eligible drivers
3776 		 * when this routine is called.  Drivers for later
3777 		 * passes should have their identify routines called
3778 		 * on early-pass buses during BUS_NEW_PASS().
3779 		 */
3780 		if (dl->pass > bus_current_pass)
3781 			continue;
3782 		DEVICE_IDENTIFY(dl->driver, dev);
3783 	}
3784 
3785 	return (0);
3786 }
3787 
3788 /**
3789  * @brief Helper function for implementing DEVICE_ATTACH()
3790  *
3791  * This function can be used to help implement the DEVICE_ATTACH() for
3792  * a bus. It calls device_probe_and_attach() for each of the device's
3793  * children.
3794  */
3795 int
3796 bus_generic_attach(device_t dev)
3797 {
3798 	device_t child;
3799 
3800 	TAILQ_FOREACH(child, &dev->children, link) {
3801 		device_probe_and_attach(child);
3802 	}
3803 
3804 	return (0);
3805 }
3806 
3807 /**
3808  * @brief Helper function for delaying attaching children
3809  *
3810  * Many buses can't run transactions on the bus which children need to probe and
3811  * attach until after interrupts and/or timers are running.  This function
3812  * delays their attach until interrupts and timers are enabled.
3813  */
3814 int
3815 bus_delayed_attach_children(device_t dev)
3816 {
3817 	/* Probe and attach the bus children when interrupts are available */
3818 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3819 
3820 	return (0);
3821 }
3822 
3823 /**
3824  * @brief Helper function for implementing DEVICE_DETACH()
3825  *
3826  * This function can be used to help implement the DEVICE_DETACH() for
3827  * a bus. It calls device_detach() for each of the device's
3828  * children.
3829  */
3830 int
3831 bus_generic_detach(device_t dev)
3832 {
3833 	device_t child;
3834 	int error;
3835 
3836 	if (dev->state != DS_ATTACHED)
3837 		return (EBUSY);
3838 
3839 	/*
3840 	 * Detach children in the reverse order.
3841 	 * See bus_generic_suspend for details.
3842 	 */
3843 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3844 		if ((error = device_detach(child)) != 0)
3845 			return (error);
3846 	}
3847 
3848 	return (0);
3849 }
3850 
3851 /**
3852  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3853  *
3854  * This function can be used to help implement the DEVICE_SHUTDOWN()
3855  * for a bus. It calls device_shutdown() for each of the device's
3856  * children.
3857  */
3858 int
3859 bus_generic_shutdown(device_t dev)
3860 {
3861 	device_t child;
3862 
3863 	/*
3864 	 * Shut down children in the reverse order.
3865 	 * See bus_generic_suspend for details.
3866 	 */
3867 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3868 		device_shutdown(child);
3869 	}
3870 
3871 	return (0);
3872 }
3873 
3874 /**
3875  * @brief Default function for suspending a child device.
3876  *
3877  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3878  */
3879 int
3880 bus_generic_suspend_child(device_t dev, device_t child)
3881 {
3882 	int	error;
3883 
3884 	error = DEVICE_SUSPEND(child);
3885 
3886 	if (error == 0)
3887 		child->flags |= DF_SUSPENDED;
3888 
3889 	return (error);
3890 }
3891 
3892 /**
3893  * @brief Default function for resuming a child device.
3894  *
3895  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3896  */
3897 int
3898 bus_generic_resume_child(device_t dev, device_t child)
3899 {
3900 	DEVICE_RESUME(child);
3901 	child->flags &= ~DF_SUSPENDED;
3902 
3903 	return (0);
3904 }
3905 
3906 /**
3907  * @brief Helper function for implementing DEVICE_SUSPEND()
3908  *
3909  * This function can be used to help implement the DEVICE_SUSPEND()
3910  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3911  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3912  * operation is aborted and any devices which were suspended are
3913  * resumed immediately by calling their DEVICE_RESUME() methods.
3914  */
3915 int
3916 bus_generic_suspend(device_t dev)
3917 {
3918 	int		error;
3919 	device_t	child;
3920 
3921 	/*
3922 	 * Suspend children in the reverse order.
3923 	 * For most buses all children are equal, so the order does not matter.
3924 	 * Other buses, such as acpi, carefully order their child devices to
3925 	 * express implicit dependencies between them.  For such buses it is
3926 	 * safer to bring down devices in the reverse order.
3927 	 */
3928 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3929 		error = BUS_SUSPEND_CHILD(dev, child);
3930 		if (error != 0) {
3931 			child = TAILQ_NEXT(child, link);
3932 			if (child != NULL) {
3933 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3934 					BUS_RESUME_CHILD(dev, child);
3935 			}
3936 			return (error);
3937 		}
3938 	}
3939 	return (0);
3940 }
3941 
3942 /**
3943  * @brief Helper function for implementing DEVICE_RESUME()
3944  *
3945  * This function can be used to help implement the DEVICE_RESUME() for
3946  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3947  */
3948 int
3949 bus_generic_resume(device_t dev)
3950 {
3951 	device_t	child;
3952 
3953 	TAILQ_FOREACH(child, &dev->children, link) {
3954 		BUS_RESUME_CHILD(dev, child);
3955 		/* if resume fails, there's nothing we can usefully do... */
3956 	}
3957 	return (0);
3958 }
3959 
3960 /**
3961  * @brief Helper function for implementing BUS_RESET_POST
3962  *
3963  * Bus can use this function to implement common operations of
3964  * re-attaching or resuming the children after the bus itself was
3965  * reset, and after restoring bus-unique state of children.
3966  *
3967  * @param dev	The bus
3968  * #param flags	DEVF_RESET_*
3969  */
3970 int
3971 bus_helper_reset_post(device_t dev, int flags)
3972 {
3973 	device_t child;
3974 	int error, error1;
3975 
3976 	error = 0;
3977 	TAILQ_FOREACH(child, &dev->children,link) {
3978 		BUS_RESET_POST(dev, child);
3979 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3980 		    device_probe_and_attach(child) :
3981 		    BUS_RESUME_CHILD(dev, child);
3982 		if (error == 0 && error1 != 0)
3983 			error = error1;
3984 	}
3985 	return (error);
3986 }
3987 
3988 static void
3989 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3990 {
3991 	child = TAILQ_NEXT(child, link);
3992 	if (child == NULL)
3993 		return;
3994 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3995 		BUS_RESET_POST(dev, child);
3996 		if ((flags & DEVF_RESET_DETACH) != 0)
3997 			device_probe_and_attach(child);
3998 		else
3999 			BUS_RESUME_CHILD(dev, child);
4000 	}
4001 }
4002 
4003 /**
4004  * @brief Helper function for implementing BUS_RESET_PREPARE
4005  *
4006  * Bus can use this function to implement common operations of
4007  * detaching or suspending the children before the bus itself is
4008  * reset, and then save bus-unique state of children that must
4009  * persists around reset.
4010  *
4011  * @param dev	The bus
4012  * #param flags	DEVF_RESET_*
4013  */
4014 int
4015 bus_helper_reset_prepare(device_t dev, int flags)
4016 {
4017 	device_t child;
4018 	int error;
4019 
4020 	if (dev->state != DS_ATTACHED)
4021 		return (EBUSY);
4022 
4023 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
4024 		if ((flags & DEVF_RESET_DETACH) != 0) {
4025 			error = device_get_state(child) == DS_ATTACHED ?
4026 			    device_detach(child) : 0;
4027 		} else {
4028 			error = BUS_SUSPEND_CHILD(dev, child);
4029 		}
4030 		if (error == 0) {
4031 			error = BUS_RESET_PREPARE(dev, child);
4032 			if (error != 0) {
4033 				if ((flags & DEVF_RESET_DETACH) != 0)
4034 					device_probe_and_attach(child);
4035 				else
4036 					BUS_RESUME_CHILD(dev, child);
4037 			}
4038 		}
4039 		if (error != 0) {
4040 			bus_helper_reset_prepare_rollback(dev, child, flags);
4041 			return (error);
4042 		}
4043 	}
4044 	return (0);
4045 }
4046 
4047 /**
4048  * @brief Helper function for implementing BUS_PRINT_CHILD().
4049  *
4050  * This function prints the first part of the ascii representation of
4051  * @p child, including its name, unit and description (if any - see
4052  * device_set_desc()).
4053  *
4054  * @returns the number of characters printed
4055  */
4056 int
4057 bus_print_child_header(device_t dev, device_t child)
4058 {
4059 	int	retval = 0;
4060 
4061 	if (device_get_desc(child)) {
4062 		retval += device_printf(child, "<%s>", device_get_desc(child));
4063 	} else {
4064 		retval += printf("%s", device_get_nameunit(child));
4065 	}
4066 
4067 	return (retval);
4068 }
4069 
4070 /**
4071  * @brief Helper function for implementing BUS_PRINT_CHILD().
4072  *
4073  * This function prints the last part of the ascii representation of
4074  * @p child, which consists of the string @c " on " followed by the
4075  * name and unit of the @p dev.
4076  *
4077  * @returns the number of characters printed
4078  */
4079 int
4080 bus_print_child_footer(device_t dev, device_t child)
4081 {
4082 	return (printf(" on %s\n", device_get_nameunit(dev)));
4083 }
4084 
4085 /**
4086  * @brief Helper function for implementing BUS_PRINT_CHILD().
4087  *
4088  * This function prints out the VM domain for the given device.
4089  *
4090  * @returns the number of characters printed
4091  */
4092 int
4093 bus_print_child_domain(device_t dev, device_t child)
4094 {
4095 	int domain;
4096 
4097 	/* No domain? Don't print anything */
4098 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4099 		return (0);
4100 
4101 	return (printf(" numa-domain %d", domain));
4102 }
4103 
4104 /**
4105  * @brief Helper function for implementing BUS_PRINT_CHILD().
4106  *
4107  * This function simply calls bus_print_child_header() followed by
4108  * bus_print_child_footer().
4109  *
4110  * @returns the number of characters printed
4111  */
4112 int
4113 bus_generic_print_child(device_t dev, device_t child)
4114 {
4115 	int	retval = 0;
4116 
4117 	retval += bus_print_child_header(dev, child);
4118 	retval += bus_print_child_domain(dev, child);
4119 	retval += bus_print_child_footer(dev, child);
4120 
4121 	return (retval);
4122 }
4123 
4124 /**
4125  * @brief Stub function for implementing BUS_READ_IVAR().
4126  *
4127  * @returns ENOENT
4128  */
4129 int
4130 bus_generic_read_ivar(device_t dev, device_t child, int index,
4131     uintptr_t * result)
4132 {
4133 	return (ENOENT);
4134 }
4135 
4136 /**
4137  * @brief Stub function for implementing BUS_WRITE_IVAR().
4138  *
4139  * @returns ENOENT
4140  */
4141 int
4142 bus_generic_write_ivar(device_t dev, device_t child, int index,
4143     uintptr_t value)
4144 {
4145 	return (ENOENT);
4146 }
4147 
4148 /**
4149  * @brief Helper function for implementing BUS_GET_PROPERTY().
4150  *
4151  * This simply calls the BUS_GET_PROPERTY of the parent of dev,
4152  * until a non-default implementation is found.
4153  */
4154 ssize_t
4155 bus_generic_get_property(device_t dev, device_t child, const char *propname,
4156     void *propvalue, size_t size, device_property_type_t type)
4157 {
4158 	if (device_get_parent(dev) != NULL)
4159 		return (BUS_GET_PROPERTY(device_get_parent(dev), child,
4160 		    propname, propvalue, size, type));
4161 
4162 	return (-1);
4163 }
4164 
4165 /**
4166  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4167  *
4168  * @returns NULL
4169  */
4170 struct resource_list *
4171 bus_generic_get_resource_list(device_t dev, device_t child)
4172 {
4173 	return (NULL);
4174 }
4175 
4176 /**
4177  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4178  *
4179  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4180  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4181  * and then calls device_probe_and_attach() for each unattached child.
4182  */
4183 void
4184 bus_generic_driver_added(device_t dev, driver_t *driver)
4185 {
4186 	device_t child;
4187 
4188 	DEVICE_IDENTIFY(driver, dev);
4189 	TAILQ_FOREACH(child, &dev->children, link) {
4190 		if (child->state == DS_NOTPRESENT)
4191 			device_probe_and_attach(child);
4192 	}
4193 }
4194 
4195 /**
4196  * @brief Helper function for implementing BUS_NEW_PASS().
4197  *
4198  * This implementing of BUS_NEW_PASS() first calls the identify
4199  * routines for any drivers that probe at the current pass.  Then it
4200  * walks the list of devices for this bus.  If a device is already
4201  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4202  * device is not already attached, it attempts to attach a driver to
4203  * it.
4204  */
4205 void
4206 bus_generic_new_pass(device_t dev)
4207 {
4208 	driverlink_t dl;
4209 	devclass_t dc;
4210 	device_t child;
4211 
4212 	dc = dev->devclass;
4213 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4214 		if (dl->pass == bus_current_pass)
4215 			DEVICE_IDENTIFY(dl->driver, dev);
4216 	}
4217 	TAILQ_FOREACH(child, &dev->children, link) {
4218 		if (child->state >= DS_ATTACHED)
4219 			BUS_NEW_PASS(child);
4220 		else if (child->state == DS_NOTPRESENT)
4221 			device_probe_and_attach(child);
4222 	}
4223 }
4224 
4225 /**
4226  * @brief Helper function for implementing BUS_SETUP_INTR().
4227  *
4228  * This simple implementation of BUS_SETUP_INTR() simply calls the
4229  * BUS_SETUP_INTR() method of the parent of @p dev.
4230  */
4231 int
4232 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4233     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4234     void **cookiep)
4235 {
4236 	/* Propagate up the bus hierarchy until someone handles it. */
4237 	if (dev->parent)
4238 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4239 		    filter, intr, arg, cookiep));
4240 	return (EINVAL);
4241 }
4242 
4243 /**
4244  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4245  *
4246  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4247  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4248  */
4249 int
4250 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4251     void *cookie)
4252 {
4253 	/* Propagate up the bus hierarchy until someone handles it. */
4254 	if (dev->parent)
4255 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4256 	return (EINVAL);
4257 }
4258 
4259 /**
4260  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4261  *
4262  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4263  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4264  */
4265 int
4266 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4267 {
4268 	/* Propagate up the bus hierarchy until someone handles it. */
4269 	if (dev->parent)
4270 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4271 	return (EINVAL);
4272 }
4273 
4274 /**
4275  * @brief Helper function for implementing BUS_RESUME_INTR().
4276  *
4277  * This simple implementation of BUS_RESUME_INTR() simply calls the
4278  * BUS_RESUME_INTR() method of the parent of @p dev.
4279  */
4280 int
4281 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4282 {
4283 	/* Propagate up the bus hierarchy until someone handles it. */
4284 	if (dev->parent)
4285 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4286 	return (EINVAL);
4287 }
4288 
4289 /**
4290  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4291  *
4292  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4293  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4294  */
4295 int
4296 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4297     struct resource *r, rman_res_t start, rman_res_t end)
4298 {
4299 	/* Propagate up the bus hierarchy until someone handles it. */
4300 	if (dev->parent)
4301 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4302 		    end));
4303 	return (EINVAL);
4304 }
4305 
4306 /*
4307  * @brief Helper function for implementing BUS_TRANSLATE_RESOURCE().
4308  *
4309  * This simple implementation of BUS_TRANSLATE_RESOURCE() simply calls the
4310  * BUS_TRANSLATE_RESOURCE() method of the parent of @p dev.  If there is no
4311  * parent, no translation happens.
4312  */
4313 int
4314 bus_generic_translate_resource(device_t dev, int type, rman_res_t start,
4315     rman_res_t *newstart)
4316 {
4317 	if (dev->parent)
4318 		return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start,
4319 		    newstart));
4320 	*newstart = start;
4321 	return (0);
4322 }
4323 
4324 /**
4325  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4326  *
4327  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4328  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4329  */
4330 struct resource *
4331 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4332     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4333 {
4334 	/* Propagate up the bus hierarchy until someone handles it. */
4335 	if (dev->parent)
4336 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4337 		    start, end, count, flags));
4338 	return (NULL);
4339 }
4340 
4341 /**
4342  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4343  *
4344  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4345  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4346  */
4347 int
4348 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4349     struct resource *r)
4350 {
4351 	/* Propagate up the bus hierarchy until someone handles it. */
4352 	if (dev->parent)
4353 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4354 		    r));
4355 	return (EINVAL);
4356 }
4357 
4358 /**
4359  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4360  *
4361  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4362  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4363  */
4364 int
4365 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4366     struct resource *r)
4367 {
4368 	/* Propagate up the bus hierarchy until someone handles it. */
4369 	if (dev->parent)
4370 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4371 		    r));
4372 	return (EINVAL);
4373 }
4374 
4375 /**
4376  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4377  *
4378  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4379  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4380  */
4381 int
4382 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4383     int rid, struct resource *r)
4384 {
4385 	/* Propagate up the bus hierarchy until someone handles it. */
4386 	if (dev->parent)
4387 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4388 		    r));
4389 	return (EINVAL);
4390 }
4391 
4392 /**
4393  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4394  *
4395  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4396  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4397  */
4398 int
4399 bus_generic_map_resource(device_t dev, device_t child, int type,
4400     struct resource *r, struct resource_map_request *args,
4401     struct resource_map *map)
4402 {
4403 	/* Propagate up the bus hierarchy until someone handles it. */
4404 	if (dev->parent)
4405 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4406 		    map));
4407 	return (EINVAL);
4408 }
4409 
4410 /**
4411  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4412  *
4413  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4414  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4415  */
4416 int
4417 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4418     struct resource *r, struct resource_map *map)
4419 {
4420 	/* Propagate up the bus hierarchy until someone handles it. */
4421 	if (dev->parent)
4422 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4423 	return (EINVAL);
4424 }
4425 
4426 /**
4427  * @brief Helper function for implementing BUS_BIND_INTR().
4428  *
4429  * This simple implementation of BUS_BIND_INTR() simply calls the
4430  * BUS_BIND_INTR() method of the parent of @p dev.
4431  */
4432 int
4433 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4434     int cpu)
4435 {
4436 	/* Propagate up the bus hierarchy until someone handles it. */
4437 	if (dev->parent)
4438 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4439 	return (EINVAL);
4440 }
4441 
4442 /**
4443  * @brief Helper function for implementing BUS_CONFIG_INTR().
4444  *
4445  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4446  * BUS_CONFIG_INTR() method of the parent of @p dev.
4447  */
4448 int
4449 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4450     enum intr_polarity pol)
4451 {
4452 	/* Propagate up the bus hierarchy until someone handles it. */
4453 	if (dev->parent)
4454 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4455 	return (EINVAL);
4456 }
4457 
4458 /**
4459  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4460  *
4461  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4462  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4463  */
4464 int
4465 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4466     void *cookie, const char *descr)
4467 {
4468 	/* Propagate up the bus hierarchy until someone handles it. */
4469 	if (dev->parent)
4470 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4471 		    descr));
4472 	return (EINVAL);
4473 }
4474 
4475 /**
4476  * @brief Helper function for implementing BUS_GET_CPUS().
4477  *
4478  * This simple implementation of BUS_GET_CPUS() simply calls the
4479  * BUS_GET_CPUS() method of the parent of @p dev.
4480  */
4481 int
4482 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4483     size_t setsize, cpuset_t *cpuset)
4484 {
4485 	/* Propagate up the bus hierarchy until someone handles it. */
4486 	if (dev->parent != NULL)
4487 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4488 	return (EINVAL);
4489 }
4490 
4491 /**
4492  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4493  *
4494  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4495  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4496  */
4497 bus_dma_tag_t
4498 bus_generic_get_dma_tag(device_t dev, device_t child)
4499 {
4500 	/* Propagate up the bus hierarchy until someone handles it. */
4501 	if (dev->parent != NULL)
4502 		return (BUS_GET_DMA_TAG(dev->parent, child));
4503 	return (NULL);
4504 }
4505 
4506 /**
4507  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4508  *
4509  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4510  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4511  */
4512 bus_space_tag_t
4513 bus_generic_get_bus_tag(device_t dev, device_t child)
4514 {
4515 	/* Propagate up the bus hierarchy until someone handles it. */
4516 	if (dev->parent != NULL)
4517 		return (BUS_GET_BUS_TAG(dev->parent, child));
4518 	return ((bus_space_tag_t)0);
4519 }
4520 
4521 /**
4522  * @brief Helper function for implementing BUS_GET_RESOURCE().
4523  *
4524  * This implementation of BUS_GET_RESOURCE() uses the
4525  * resource_list_find() function to do most of the work. It calls
4526  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4527  * search.
4528  */
4529 int
4530 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4531     rman_res_t *startp, rman_res_t *countp)
4532 {
4533 	struct resource_list *		rl = NULL;
4534 	struct resource_list_entry *	rle = NULL;
4535 
4536 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4537 	if (!rl)
4538 		return (EINVAL);
4539 
4540 	rle = resource_list_find(rl, type, rid);
4541 	if (!rle)
4542 		return (ENOENT);
4543 
4544 	if (startp)
4545 		*startp = rle->start;
4546 	if (countp)
4547 		*countp = rle->count;
4548 
4549 	return (0);
4550 }
4551 
4552 /**
4553  * @brief Helper function for implementing BUS_SET_RESOURCE().
4554  *
4555  * This implementation of BUS_SET_RESOURCE() uses the
4556  * resource_list_add() function to do most of the work. It calls
4557  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4558  * edit.
4559  */
4560 int
4561 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4562     rman_res_t start, rman_res_t count)
4563 {
4564 	struct resource_list *		rl = NULL;
4565 
4566 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4567 	if (!rl)
4568 		return (EINVAL);
4569 
4570 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4571 
4572 	return (0);
4573 }
4574 
4575 /**
4576  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4577  *
4578  * This implementation of BUS_DELETE_RESOURCE() uses the
4579  * resource_list_delete() function to do most of the work. It calls
4580  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4581  * edit.
4582  */
4583 void
4584 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4585 {
4586 	struct resource_list *		rl = NULL;
4587 
4588 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4589 	if (!rl)
4590 		return;
4591 
4592 	resource_list_delete(rl, type, rid);
4593 
4594 	return;
4595 }
4596 
4597 /**
4598  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4599  *
4600  * This implementation of BUS_RELEASE_RESOURCE() uses the
4601  * resource_list_release() function to do most of the work. It calls
4602  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4603  */
4604 int
4605 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4606     int rid, struct resource *r)
4607 {
4608 	struct resource_list *		rl = NULL;
4609 
4610 	if (device_get_parent(child) != dev)
4611 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4612 		    type, rid, r));
4613 
4614 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4615 	if (!rl)
4616 		return (EINVAL);
4617 
4618 	return (resource_list_release(rl, dev, child, type, rid, r));
4619 }
4620 
4621 /**
4622  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4623  *
4624  * This implementation of BUS_ALLOC_RESOURCE() uses the
4625  * resource_list_alloc() function to do most of the work. It calls
4626  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4627  */
4628 struct resource *
4629 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4630     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4631 {
4632 	struct resource_list *		rl = NULL;
4633 
4634 	if (device_get_parent(child) != dev)
4635 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4636 		    type, rid, start, end, count, flags));
4637 
4638 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4639 	if (!rl)
4640 		return (NULL);
4641 
4642 	return (resource_list_alloc(rl, dev, child, type, rid,
4643 	    start, end, count, flags));
4644 }
4645 
4646 /**
4647  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4648  *
4649  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4650  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4651  */
4652 int
4653 bus_generic_child_present(device_t dev, device_t child)
4654 {
4655 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4656 }
4657 
4658 int
4659 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4660 {
4661 	if (dev->parent)
4662 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4663 
4664 	return (ENOENT);
4665 }
4666 
4667 /**
4668  * @brief Helper function to implement normal BUS_GET_DEVICE_PATH()
4669  *
4670  * This function knows how to (a) pass the request up the tree if there's
4671  * a parent and (b) Knows how to supply a FreeBSD locator.
4672  *
4673  * @param bus		bus in the walk up the tree
4674  * @param child		leaf node to print information about
4675  * @param locator	BUS_LOCATOR_xxx string for locator
4676  * @param sb		Buffer to print information into
4677  */
4678 int
4679 bus_generic_get_device_path(device_t bus, device_t child, const char *locator,
4680     struct sbuf *sb)
4681 {
4682 	int rv = 0;
4683 	device_t parent;
4684 
4685 	/*
4686 	 * We don't recurse on ACPI since either we know the handle for the
4687 	 * device or we don't. And if we're in the generic routine, we don't
4688 	 * have a ACPI override. All other locators build up a path by having
4689 	 * their parents create a path and then adding the path element for this
4690 	 * node. That's why we recurse with parent, bus rather than the typical
4691 	 * parent, child: each spot in the tree is independent of what our child
4692 	 * will do with this path.
4693 	 */
4694 	parent = device_get_parent(bus);
4695 	if (parent != NULL && strcmp(locator, BUS_LOCATOR_ACPI) != 0) {
4696 		rv = BUS_GET_DEVICE_PATH(parent, bus, locator, sb);
4697 	}
4698 	if (strcmp(locator, BUS_LOCATOR_FREEBSD) == 0) {
4699 		if (rv == 0) {
4700 			sbuf_printf(sb, "/%s", device_get_nameunit(child));
4701 		}
4702 		return (rv);
4703 	}
4704 	/*
4705 	 * Don't know what to do. So assume we do nothing. Not sure that's
4706 	 * the right thing, but keeps us from having a big list here.
4707 	 */
4708 	return (0);
4709 }
4710 
4711 
4712 /**
4713  * @brief Helper function for implementing BUS_RESCAN().
4714  *
4715  * This null implementation of BUS_RESCAN() always fails to indicate
4716  * the bus does not support rescanning.
4717  */
4718 int
4719 bus_null_rescan(device_t dev)
4720 {
4721 	return (ENODEV);
4722 }
4723 
4724 /*
4725  * Some convenience functions to make it easier for drivers to use the
4726  * resource-management functions.  All these really do is hide the
4727  * indirection through the parent's method table, making for slightly
4728  * less-wordy code.  In the future, it might make sense for this code
4729  * to maintain some sort of a list of resources allocated by each device.
4730  */
4731 
4732 int
4733 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4734     struct resource **res)
4735 {
4736 	int i;
4737 
4738 	for (i = 0; rs[i].type != -1; i++)
4739 		res[i] = NULL;
4740 	for (i = 0; rs[i].type != -1; i++) {
4741 		res[i] = bus_alloc_resource_any(dev,
4742 		    rs[i].type, &rs[i].rid, rs[i].flags);
4743 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4744 			bus_release_resources(dev, rs, res);
4745 			return (ENXIO);
4746 		}
4747 	}
4748 	return (0);
4749 }
4750 
4751 void
4752 bus_release_resources(device_t dev, const struct resource_spec *rs,
4753     struct resource **res)
4754 {
4755 	int i;
4756 
4757 	for (i = 0; rs[i].type != -1; i++)
4758 		if (res[i] != NULL) {
4759 			bus_release_resource(
4760 			    dev, rs[i].type, rs[i].rid, res[i]);
4761 			res[i] = NULL;
4762 		}
4763 }
4764 
4765 /**
4766  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4767  *
4768  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4769  * parent of @p dev.
4770  */
4771 struct resource *
4772 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4773     rman_res_t end, rman_res_t count, u_int flags)
4774 {
4775 	struct resource *res;
4776 
4777 	if (dev->parent == NULL)
4778 		return (NULL);
4779 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4780 	    count, flags);
4781 	return (res);
4782 }
4783 
4784 /**
4785  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4786  *
4787  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4788  * parent of @p dev.
4789  */
4790 int
4791 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4792     rman_res_t end)
4793 {
4794 	if (dev->parent == NULL)
4795 		return (EINVAL);
4796 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4797 }
4798 
4799 /**
4800  * @brief Wrapper function for BUS_TRANSLATE_RESOURCE().
4801  *
4802  * This function simply calls the BUS_TRANSLATE_RESOURCE() method of the
4803  * parent of @p dev.
4804  */
4805 int
4806 bus_translate_resource(device_t dev, int type, rman_res_t start,
4807     rman_res_t *newstart)
4808 {
4809 	if (dev->parent == NULL)
4810 		return (EINVAL);
4811 	return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start, newstart));
4812 }
4813 
4814 /**
4815  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4816  *
4817  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4818  * parent of @p dev.
4819  */
4820 int
4821 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4822 {
4823 	if (dev->parent == NULL)
4824 		return (EINVAL);
4825 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4826 }
4827 
4828 /**
4829  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4830  *
4831  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4832  * parent of @p dev.
4833  */
4834 int
4835 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4836 {
4837 	if (dev->parent == NULL)
4838 		return (EINVAL);
4839 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4840 }
4841 
4842 /**
4843  * @brief Wrapper function for BUS_MAP_RESOURCE().
4844  *
4845  * This function simply calls the BUS_MAP_RESOURCE() method of the
4846  * parent of @p dev.
4847  */
4848 int
4849 bus_map_resource(device_t dev, int type, struct resource *r,
4850     struct resource_map_request *args, struct resource_map *map)
4851 {
4852 	if (dev->parent == NULL)
4853 		return (EINVAL);
4854 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4855 }
4856 
4857 /**
4858  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4859  *
4860  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4861  * parent of @p dev.
4862  */
4863 int
4864 bus_unmap_resource(device_t dev, int type, struct resource *r,
4865     struct resource_map *map)
4866 {
4867 	if (dev->parent == NULL)
4868 		return (EINVAL);
4869 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4870 }
4871 
4872 /**
4873  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4874  *
4875  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4876  * parent of @p dev.
4877  */
4878 int
4879 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4880 {
4881 	int rv;
4882 
4883 	if (dev->parent == NULL)
4884 		return (EINVAL);
4885 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4886 	return (rv);
4887 }
4888 
4889 /**
4890  * @brief Wrapper function for BUS_SETUP_INTR().
4891  *
4892  * This function simply calls the BUS_SETUP_INTR() method of the
4893  * parent of @p dev.
4894  */
4895 int
4896 bus_setup_intr(device_t dev, struct resource *r, int flags,
4897     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4898 {
4899 	int error;
4900 
4901 	if (dev->parent == NULL)
4902 		return (EINVAL);
4903 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4904 	    arg, cookiep);
4905 	if (error != 0)
4906 		return (error);
4907 	if (handler != NULL && !(flags & INTR_MPSAFE))
4908 		device_printf(dev, "[GIANT-LOCKED]\n");
4909 	return (0);
4910 }
4911 
4912 /**
4913  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4914  *
4915  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4916  * parent of @p dev.
4917  */
4918 int
4919 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4920 {
4921 	if (dev->parent == NULL)
4922 		return (EINVAL);
4923 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4924 }
4925 
4926 /**
4927  * @brief Wrapper function for BUS_SUSPEND_INTR().
4928  *
4929  * This function simply calls the BUS_SUSPEND_INTR() method of the
4930  * parent of @p dev.
4931  */
4932 int
4933 bus_suspend_intr(device_t dev, struct resource *r)
4934 {
4935 	if (dev->parent == NULL)
4936 		return (EINVAL);
4937 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4938 }
4939 
4940 /**
4941  * @brief Wrapper function for BUS_RESUME_INTR().
4942  *
4943  * This function simply calls the BUS_RESUME_INTR() method of the
4944  * parent of @p dev.
4945  */
4946 int
4947 bus_resume_intr(device_t dev, struct resource *r)
4948 {
4949 	if (dev->parent == NULL)
4950 		return (EINVAL);
4951 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4952 }
4953 
4954 /**
4955  * @brief Wrapper function for BUS_BIND_INTR().
4956  *
4957  * This function simply calls the BUS_BIND_INTR() method of the
4958  * parent of @p dev.
4959  */
4960 int
4961 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4962 {
4963 	if (dev->parent == NULL)
4964 		return (EINVAL);
4965 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4966 }
4967 
4968 /**
4969  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4970  *
4971  * This function first formats the requested description into a
4972  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4973  * the parent of @p dev.
4974  */
4975 int
4976 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4977     const char *fmt, ...)
4978 {
4979 	va_list ap;
4980 	char descr[MAXCOMLEN + 1];
4981 
4982 	if (dev->parent == NULL)
4983 		return (EINVAL);
4984 	va_start(ap, fmt);
4985 	vsnprintf(descr, sizeof(descr), fmt, ap);
4986 	va_end(ap);
4987 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4988 }
4989 
4990 /**
4991  * @brief Wrapper function for BUS_SET_RESOURCE().
4992  *
4993  * This function simply calls the BUS_SET_RESOURCE() method of the
4994  * parent of @p dev.
4995  */
4996 int
4997 bus_set_resource(device_t dev, int type, int rid,
4998     rman_res_t start, rman_res_t count)
4999 {
5000 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
5001 	    start, count));
5002 }
5003 
5004 /**
5005  * @brief Wrapper function for BUS_GET_RESOURCE().
5006  *
5007  * This function simply calls the BUS_GET_RESOURCE() method of the
5008  * parent of @p dev.
5009  */
5010 int
5011 bus_get_resource(device_t dev, int type, int rid,
5012     rman_res_t *startp, rman_res_t *countp)
5013 {
5014 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5015 	    startp, countp));
5016 }
5017 
5018 /**
5019  * @brief Wrapper function for BUS_GET_RESOURCE().
5020  *
5021  * This function simply calls the BUS_GET_RESOURCE() method of the
5022  * parent of @p dev and returns the start value.
5023  */
5024 rman_res_t
5025 bus_get_resource_start(device_t dev, int type, int rid)
5026 {
5027 	rman_res_t start;
5028 	rman_res_t count;
5029 	int error;
5030 
5031 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5032 	    &start, &count);
5033 	if (error)
5034 		return (0);
5035 	return (start);
5036 }
5037 
5038 /**
5039  * @brief Wrapper function for BUS_GET_RESOURCE().
5040  *
5041  * This function simply calls the BUS_GET_RESOURCE() method of the
5042  * parent of @p dev and returns the count value.
5043  */
5044 rman_res_t
5045 bus_get_resource_count(device_t dev, int type, int rid)
5046 {
5047 	rman_res_t start;
5048 	rman_res_t count;
5049 	int error;
5050 
5051 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5052 	    &start, &count);
5053 	if (error)
5054 		return (0);
5055 	return (count);
5056 }
5057 
5058 /**
5059  * @brief Wrapper function for BUS_DELETE_RESOURCE().
5060  *
5061  * This function simply calls the BUS_DELETE_RESOURCE() method of the
5062  * parent of @p dev.
5063  */
5064 void
5065 bus_delete_resource(device_t dev, int type, int rid)
5066 {
5067 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
5068 }
5069 
5070 /**
5071  * @brief Wrapper function for BUS_CHILD_PRESENT().
5072  *
5073  * This function simply calls the BUS_CHILD_PRESENT() method of the
5074  * parent of @p dev.
5075  */
5076 int
5077 bus_child_present(device_t child)
5078 {
5079 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
5080 }
5081 
5082 /**
5083  * @brief Wrapper function for BUS_CHILD_PNPINFO().
5084  *
5085  * This function simply calls the BUS_CHILD_PNPINFO() method of the parent of @p
5086  * dev.
5087  */
5088 int
5089 bus_child_pnpinfo(device_t child, struct sbuf *sb)
5090 {
5091 	device_t parent;
5092 
5093 	parent = device_get_parent(child);
5094 	if (parent == NULL)
5095 		return (0);
5096 	return (BUS_CHILD_PNPINFO(parent, child, sb));
5097 }
5098 
5099 /**
5100  * @brief Generic implementation that does nothing for bus_child_pnpinfo
5101  *
5102  * This function has the right signature and returns 0 since the sbuf is passed
5103  * to us to append to.
5104  */
5105 int
5106 bus_generic_child_pnpinfo(device_t dev, device_t child, struct sbuf *sb)
5107 {
5108 	return (0);
5109 }
5110 
5111 /**
5112  * @brief Wrapper function for BUS_CHILD_LOCATION().
5113  *
5114  * This function simply calls the BUS_CHILD_LOCATION() method of the parent of
5115  * @p dev.
5116  */
5117 int
5118 bus_child_location(device_t child, struct sbuf *sb)
5119 {
5120 	device_t parent;
5121 
5122 	parent = device_get_parent(child);
5123 	if (parent == NULL)
5124 		return (0);
5125 	return (BUS_CHILD_LOCATION(parent, child, sb));
5126 }
5127 
5128 /**
5129  * @brief Generic implementation that does nothing for bus_child_location
5130  *
5131  * This function has the right signature and returns 0 since the sbuf is passed
5132  * to us to append to.
5133  */
5134 int
5135 bus_generic_child_location(device_t dev, device_t child, struct sbuf *sb)
5136 {
5137 	return (0);
5138 }
5139 
5140 /**
5141  * @brief Wrapper function for BUS_GET_CPUS().
5142  *
5143  * This function simply calls the BUS_GET_CPUS() method of the
5144  * parent of @p dev.
5145  */
5146 int
5147 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5148 {
5149 	device_t parent;
5150 
5151 	parent = device_get_parent(dev);
5152 	if (parent == NULL)
5153 		return (EINVAL);
5154 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5155 }
5156 
5157 /**
5158  * @brief Wrapper function for BUS_GET_DMA_TAG().
5159  *
5160  * This function simply calls the BUS_GET_DMA_TAG() method of the
5161  * parent of @p dev.
5162  */
5163 bus_dma_tag_t
5164 bus_get_dma_tag(device_t dev)
5165 {
5166 	device_t parent;
5167 
5168 	parent = device_get_parent(dev);
5169 	if (parent == NULL)
5170 		return (NULL);
5171 	return (BUS_GET_DMA_TAG(parent, dev));
5172 }
5173 
5174 /**
5175  * @brief Wrapper function for BUS_GET_BUS_TAG().
5176  *
5177  * This function simply calls the BUS_GET_BUS_TAG() method of the
5178  * parent of @p dev.
5179  */
5180 bus_space_tag_t
5181 bus_get_bus_tag(device_t dev)
5182 {
5183 	device_t parent;
5184 
5185 	parent = device_get_parent(dev);
5186 	if (parent == NULL)
5187 		return ((bus_space_tag_t)0);
5188 	return (BUS_GET_BUS_TAG(parent, dev));
5189 }
5190 
5191 /**
5192  * @brief Wrapper function for BUS_GET_DOMAIN().
5193  *
5194  * This function simply calls the BUS_GET_DOMAIN() method of the
5195  * parent of @p dev.
5196  */
5197 int
5198 bus_get_domain(device_t dev, int *domain)
5199 {
5200 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5201 }
5202 
5203 /* Resume all devices and then notify userland that we're up again. */
5204 static int
5205 root_resume(device_t dev)
5206 {
5207 	int error;
5208 
5209 	error = bus_generic_resume(dev);
5210 	if (error == 0) {
5211 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5212 		devctl_notify("kernel", "power", "resume", NULL);
5213 	}
5214 	return (error);
5215 }
5216 
5217 static int
5218 root_print_child(device_t dev, device_t child)
5219 {
5220 	int	retval = 0;
5221 
5222 	retval += bus_print_child_header(dev, child);
5223 	retval += printf("\n");
5224 
5225 	return (retval);
5226 }
5227 
5228 static int
5229 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5230     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5231 {
5232 	/*
5233 	 * If an interrupt mapping gets to here something bad has happened.
5234 	 */
5235 	panic("root_setup_intr");
5236 }
5237 
5238 /*
5239  * If we get here, assume that the device is permanent and really is
5240  * present in the system.  Removable bus drivers are expected to intercept
5241  * this call long before it gets here.  We return -1 so that drivers that
5242  * really care can check vs -1 or some ERRNO returned higher in the food
5243  * chain.
5244  */
5245 static int
5246 root_child_present(device_t dev, device_t child)
5247 {
5248 	return (-1);
5249 }
5250 
5251 static int
5252 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5253     cpuset_t *cpuset)
5254 {
5255 	switch (op) {
5256 	case INTR_CPUS:
5257 		/* Default to returning the set of all CPUs. */
5258 		if (setsize != sizeof(cpuset_t))
5259 			return (EINVAL);
5260 		*cpuset = all_cpus;
5261 		return (0);
5262 	default:
5263 		return (EINVAL);
5264 	}
5265 }
5266 
5267 static kobj_method_t root_methods[] = {
5268 	/* Device interface */
5269 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5270 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5271 	KOBJMETHOD(device_resume,	root_resume),
5272 
5273 	/* Bus interface */
5274 	KOBJMETHOD(bus_print_child,	root_print_child),
5275 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5276 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5277 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5278 	KOBJMETHOD(bus_child_present,	root_child_present),
5279 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5280 
5281 	KOBJMETHOD_END
5282 };
5283 
5284 static driver_t root_driver = {
5285 	"root",
5286 	root_methods,
5287 	1,			/* no softc */
5288 };
5289 
5290 device_t	root_bus;
5291 devclass_t	root_devclass;
5292 
5293 static int
5294 root_bus_module_handler(module_t mod, int what, void* arg)
5295 {
5296 	switch (what) {
5297 	case MOD_LOAD:
5298 		TAILQ_INIT(&bus_data_devices);
5299 		kobj_class_compile((kobj_class_t) &root_driver);
5300 		root_bus = make_device(NULL, "root", 0);
5301 		root_bus->desc = "System root bus";
5302 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5303 		root_bus->driver = &root_driver;
5304 		root_bus->state = DS_ATTACHED;
5305 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5306 		devinit();
5307 		return (0);
5308 
5309 	case MOD_SHUTDOWN:
5310 		device_shutdown(root_bus);
5311 		return (0);
5312 	default:
5313 		return (EOPNOTSUPP);
5314 	}
5315 
5316 	return (0);
5317 }
5318 
5319 static moduledata_t root_bus_mod = {
5320 	"rootbus",
5321 	root_bus_module_handler,
5322 	NULL
5323 };
5324 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5325 
5326 /**
5327  * @brief Automatically configure devices
5328  *
5329  * This function begins the autoconfiguration process by calling
5330  * device_probe_and_attach() for each child of the @c root0 device.
5331  */
5332 void
5333 root_bus_configure(void)
5334 {
5335 	PDEBUG(("."));
5336 
5337 	/* Eventually this will be split up, but this is sufficient for now. */
5338 	bus_set_pass(BUS_PASS_DEFAULT);
5339 }
5340 
5341 /**
5342  * @brief Module handler for registering device drivers
5343  *
5344  * This module handler is used to automatically register device
5345  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5346  * devclass_add_driver() for the driver described by the
5347  * driver_module_data structure pointed to by @p arg
5348  */
5349 int
5350 driver_module_handler(module_t mod, int what, void *arg)
5351 {
5352 	struct driver_module_data *dmd;
5353 	devclass_t bus_devclass;
5354 	kobj_class_t driver;
5355 	int error, pass;
5356 
5357 	dmd = (struct driver_module_data *)arg;
5358 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5359 	error = 0;
5360 
5361 	switch (what) {
5362 	case MOD_LOAD:
5363 		if (dmd->dmd_chainevh)
5364 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5365 
5366 		pass = dmd->dmd_pass;
5367 		driver = dmd->dmd_driver;
5368 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5369 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5370 		error = devclass_add_driver(bus_devclass, driver, pass,
5371 		    dmd->dmd_devclass);
5372 		break;
5373 
5374 	case MOD_UNLOAD:
5375 		PDEBUG(("Unloading module: driver %s from bus %s",
5376 		    DRIVERNAME(dmd->dmd_driver),
5377 		    dmd->dmd_busname));
5378 		error = devclass_delete_driver(bus_devclass,
5379 		    dmd->dmd_driver);
5380 
5381 		if (!error && dmd->dmd_chainevh)
5382 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5383 		break;
5384 	case MOD_QUIESCE:
5385 		PDEBUG(("Quiesce module: driver %s from bus %s",
5386 		    DRIVERNAME(dmd->dmd_driver),
5387 		    dmd->dmd_busname));
5388 		error = devclass_quiesce_driver(bus_devclass,
5389 		    dmd->dmd_driver);
5390 
5391 		if (!error && dmd->dmd_chainevh)
5392 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5393 		break;
5394 	default:
5395 		error = EOPNOTSUPP;
5396 		break;
5397 	}
5398 
5399 	return (error);
5400 }
5401 
5402 /**
5403  * @brief Enumerate all hinted devices for this bus.
5404  *
5405  * Walks through the hints for this bus and calls the bus_hinted_child
5406  * routine for each one it fines.  It searches first for the specific
5407  * bus that's being probed for hinted children (eg isa0), and then for
5408  * generic children (eg isa).
5409  *
5410  * @param	dev	bus device to enumerate
5411  */
5412 void
5413 bus_enumerate_hinted_children(device_t bus)
5414 {
5415 	int i;
5416 	const char *dname, *busname;
5417 	int dunit;
5418 
5419 	/*
5420 	 * enumerate all devices on the specific bus
5421 	 */
5422 	busname = device_get_nameunit(bus);
5423 	i = 0;
5424 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5425 		BUS_HINTED_CHILD(bus, dname, dunit);
5426 
5427 	/*
5428 	 * and all the generic ones.
5429 	 */
5430 	busname = device_get_name(bus);
5431 	i = 0;
5432 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5433 		BUS_HINTED_CHILD(bus, dname, dunit);
5434 }
5435 
5436 #ifdef BUS_DEBUG
5437 
5438 /* the _short versions avoid iteration by not calling anything that prints
5439  * more than oneliners. I love oneliners.
5440  */
5441 
5442 static void
5443 print_device_short(device_t dev, int indent)
5444 {
5445 	if (!dev)
5446 		return;
5447 
5448 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5449 	    dev->unit, dev->desc,
5450 	    (dev->parent? "":"no "),
5451 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5452 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5453 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5454 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5455 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5456 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5457 	    (dev->ivars? "":"no "),
5458 	    (dev->softc? "":"no "),
5459 	    dev->busy));
5460 }
5461 
5462 static void
5463 print_device(device_t dev, int indent)
5464 {
5465 	if (!dev)
5466 		return;
5467 
5468 	print_device_short(dev, indent);
5469 
5470 	indentprintf(("Parent:\n"));
5471 	print_device_short(dev->parent, indent+1);
5472 	indentprintf(("Driver:\n"));
5473 	print_driver_short(dev->driver, indent+1);
5474 	indentprintf(("Devclass:\n"));
5475 	print_devclass_short(dev->devclass, indent+1);
5476 }
5477 
5478 void
5479 print_device_tree_short(device_t dev, int indent)
5480 /* print the device and all its children (indented) */
5481 {
5482 	device_t child;
5483 
5484 	if (!dev)
5485 		return;
5486 
5487 	print_device_short(dev, indent);
5488 
5489 	TAILQ_FOREACH(child, &dev->children, link) {
5490 		print_device_tree_short(child, indent+1);
5491 	}
5492 }
5493 
5494 void
5495 print_device_tree(device_t dev, int indent)
5496 /* print the device and all its children (indented) */
5497 {
5498 	device_t child;
5499 
5500 	if (!dev)
5501 		return;
5502 
5503 	print_device(dev, indent);
5504 
5505 	TAILQ_FOREACH(child, &dev->children, link) {
5506 		print_device_tree(child, indent+1);
5507 	}
5508 }
5509 
5510 static void
5511 print_driver_short(driver_t *driver, int indent)
5512 {
5513 	if (!driver)
5514 		return;
5515 
5516 	indentprintf(("driver %s: softc size = %zd\n",
5517 	    driver->name, driver->size));
5518 }
5519 
5520 static void
5521 print_driver(driver_t *driver, int indent)
5522 {
5523 	if (!driver)
5524 		return;
5525 
5526 	print_driver_short(driver, indent);
5527 }
5528 
5529 static void
5530 print_driver_list(driver_list_t drivers, int indent)
5531 {
5532 	driverlink_t driver;
5533 
5534 	TAILQ_FOREACH(driver, &drivers, link) {
5535 		print_driver(driver->driver, indent);
5536 	}
5537 }
5538 
5539 static void
5540 print_devclass_short(devclass_t dc, int indent)
5541 {
5542 	if ( !dc )
5543 		return;
5544 
5545 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5546 }
5547 
5548 static void
5549 print_devclass(devclass_t dc, int indent)
5550 {
5551 	int i;
5552 
5553 	if ( !dc )
5554 		return;
5555 
5556 	print_devclass_short(dc, indent);
5557 	indentprintf(("Drivers:\n"));
5558 	print_driver_list(dc->drivers, indent+1);
5559 
5560 	indentprintf(("Devices:\n"));
5561 	for (i = 0; i < dc->maxunit; i++)
5562 		if (dc->devices[i])
5563 			print_device(dc->devices[i], indent+1);
5564 }
5565 
5566 void
5567 print_devclass_list_short(void)
5568 {
5569 	devclass_t dc;
5570 
5571 	printf("Short listing of devclasses, drivers & devices:\n");
5572 	TAILQ_FOREACH(dc, &devclasses, link) {
5573 		print_devclass_short(dc, 0);
5574 	}
5575 }
5576 
5577 void
5578 print_devclass_list(void)
5579 {
5580 	devclass_t dc;
5581 
5582 	printf("Full listing of devclasses, drivers & devices:\n");
5583 	TAILQ_FOREACH(dc, &devclasses, link) {
5584 		print_devclass(dc, 0);
5585 	}
5586 }
5587 
5588 #endif
5589 
5590 /*
5591  * User-space access to the device tree.
5592  *
5593  * We implement a small set of nodes:
5594  *
5595  * hw.bus			Single integer read method to obtain the
5596  *				current generation count.
5597  * hw.bus.devices		Reads the entire device tree in flat space.
5598  * hw.bus.rman			Resource manager interface
5599  *
5600  * We might like to add the ability to scan devclasses and/or drivers to
5601  * determine what else is currently loaded/available.
5602  */
5603 
5604 static int
5605 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5606 {
5607 	struct u_businfo	ubus;
5608 
5609 	ubus.ub_version = BUS_USER_VERSION;
5610 	ubus.ub_generation = bus_data_generation;
5611 
5612 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5613 }
5614 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5615     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5616     "bus-related data");
5617 
5618 static int
5619 sysctl_devices(SYSCTL_HANDLER_ARGS)
5620 {
5621 	struct sbuf		sb;
5622 	int			*name = (int *)arg1;
5623 	u_int			namelen = arg2;
5624 	int			index;
5625 	device_t		dev;
5626 	struct u_device		*udev;
5627 	int			error;
5628 
5629 	if (namelen != 2)
5630 		return (EINVAL);
5631 
5632 	if (bus_data_generation_check(name[0]))
5633 		return (EINVAL);
5634 
5635 	index = name[1];
5636 
5637 	/*
5638 	 * Scan the list of devices, looking for the requested index.
5639 	 */
5640 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5641 		if (index-- == 0)
5642 			break;
5643 	}
5644 	if (dev == NULL)
5645 		return (ENOENT);
5646 
5647 	/*
5648 	 * Populate the return item, careful not to overflow the buffer.
5649 	 */
5650 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5651 	if (udev == NULL)
5652 		return (ENOMEM);
5653 	udev->dv_handle = (uintptr_t)dev;
5654 	udev->dv_parent = (uintptr_t)dev->parent;
5655 	udev->dv_devflags = dev->devflags;
5656 	udev->dv_flags = dev->flags;
5657 	udev->dv_state = dev->state;
5658 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5659 	if (dev->nameunit != NULL)
5660 		sbuf_cat(&sb, dev->nameunit);
5661 	sbuf_putc(&sb, '\0');
5662 	if (dev->desc != NULL)
5663 		sbuf_cat(&sb, dev->desc);
5664 	sbuf_putc(&sb, '\0');
5665 	if (dev->driver != NULL)
5666 		sbuf_cat(&sb, dev->driver->name);
5667 	sbuf_putc(&sb, '\0');
5668 	bus_child_pnpinfo(dev, &sb);
5669 	sbuf_putc(&sb, '\0');
5670 	bus_child_location(dev, &sb);
5671 	sbuf_putc(&sb, '\0');
5672 	error = sbuf_finish(&sb);
5673 	if (error == 0)
5674 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5675 	sbuf_delete(&sb);
5676 	free(udev, M_BUS);
5677 	return (error);
5678 }
5679 
5680 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5681     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5682     "system device tree");
5683 
5684 int
5685 bus_data_generation_check(int generation)
5686 {
5687 	if (generation != bus_data_generation)
5688 		return (1);
5689 
5690 	/* XXX generate optimised lists here? */
5691 	return (0);
5692 }
5693 
5694 void
5695 bus_data_generation_update(void)
5696 {
5697 	atomic_add_int(&bus_data_generation, 1);
5698 }
5699 
5700 int
5701 bus_free_resource(device_t dev, int type, struct resource *r)
5702 {
5703 	if (r == NULL)
5704 		return (0);
5705 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5706 }
5707 
5708 device_t
5709 device_lookup_by_name(const char *name)
5710 {
5711 	device_t dev;
5712 
5713 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5714 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5715 			return (dev);
5716 	}
5717 	return (NULL);
5718 }
5719 
5720 /*
5721  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5722  * implicit semantics on open, so it could not be reused for this.
5723  * Another option would be to call this /dev/bus?
5724  */
5725 static int
5726 find_device(struct devreq *req, device_t *devp)
5727 {
5728 	device_t dev;
5729 
5730 	/*
5731 	 * First, ensure that the name is nul terminated.
5732 	 */
5733 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5734 		return (EINVAL);
5735 
5736 	/*
5737 	 * Second, try to find an attached device whose name matches
5738 	 * 'name'.
5739 	 */
5740 	dev = device_lookup_by_name(req->dr_name);
5741 	if (dev != NULL) {
5742 		*devp = dev;
5743 		return (0);
5744 	}
5745 
5746 	/* Finally, give device enumerators a chance. */
5747 	dev = NULL;
5748 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5749 	if (dev == NULL)
5750 		return (ENOENT);
5751 	*devp = dev;
5752 	return (0);
5753 }
5754 
5755 static bool
5756 driver_exists(device_t bus, const char *driver)
5757 {
5758 	devclass_t dc;
5759 
5760 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5761 		if (devclass_find_driver_internal(dc, driver) != NULL)
5762 			return (true);
5763 	}
5764 	return (false);
5765 }
5766 
5767 static void
5768 device_gen_nomatch(device_t dev)
5769 {
5770 	device_t child;
5771 
5772 	if (dev->flags & DF_NEEDNOMATCH &&
5773 	    dev->state == DS_NOTPRESENT) {
5774 		BUS_PROBE_NOMATCH(dev->parent, dev);
5775 		devnomatch(dev);
5776 		dev->flags |= DF_DONENOMATCH;
5777 	}
5778 	dev->flags &= ~DF_NEEDNOMATCH;
5779 	TAILQ_FOREACH(child, &dev->children, link) {
5780 		device_gen_nomatch(child);
5781 	}
5782 }
5783 
5784 static void
5785 device_do_deferred_actions(void)
5786 {
5787 	devclass_t dc;
5788 	driverlink_t dl;
5789 
5790 	/*
5791 	 * Walk through the devclasses to find all the drivers we've tagged as
5792 	 * deferred during the freeze and call the driver added routines. They
5793 	 * have already been added to the lists in the background, so the driver
5794 	 * added routines that trigger a probe will have all the right bidders
5795 	 * for the probe auction.
5796 	 */
5797 	TAILQ_FOREACH(dc, &devclasses, link) {
5798 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5799 			if (dl->flags & DL_DEFERRED_PROBE) {
5800 				devclass_driver_added(dc, dl->driver);
5801 				dl->flags &= ~DL_DEFERRED_PROBE;
5802 			}
5803 		}
5804 	}
5805 
5806 	/*
5807 	 * We also defer no-match events during a freeze. Walk the tree and
5808 	 * generate all the pent-up events that are still relevant.
5809 	 */
5810 	device_gen_nomatch(root_bus);
5811 	bus_data_generation_update();
5812 }
5813 
5814 static char *
5815 device_get_path(device_t dev, const char *locator)
5816 {
5817 	struct sbuf *sb;
5818 	ssize_t len;
5819 	char *rv = NULL;
5820 	int error;
5821 
5822 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | SBUF_INCLUDENUL);
5823 	error = BUS_GET_DEVICE_PATH(device_get_parent(dev), dev, locator, sb);
5824 	sbuf_finish(sb);	/* Note: errors checked with sbuf_len() below */
5825 	if (error != 0)
5826 		goto out;
5827 	len = sbuf_len(sb);
5828 	if (len <= 1)
5829 		goto out;
5830 	rv = malloc(len, M_BUS, M_NOWAIT);
5831 	memcpy(rv, sbuf_data(sb), len);
5832 out:
5833 	sbuf_delete(sb);
5834 	return (rv);
5835 }
5836 
5837 static int
5838 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5839     struct thread *td)
5840 {
5841 	struct devreq *req;
5842 	device_t dev;
5843 	int error, old;
5844 
5845 	/* Locate the device to control. */
5846 	bus_topo_lock();
5847 	req = (struct devreq *)data;
5848 	switch (cmd) {
5849 	case DEV_ATTACH:
5850 	case DEV_DETACH:
5851 	case DEV_ENABLE:
5852 	case DEV_DISABLE:
5853 	case DEV_SUSPEND:
5854 	case DEV_RESUME:
5855 	case DEV_SET_DRIVER:
5856 	case DEV_CLEAR_DRIVER:
5857 	case DEV_RESCAN:
5858 	case DEV_DELETE:
5859 	case DEV_RESET:
5860 		error = priv_check(td, PRIV_DRIVER);
5861 		if (error == 0)
5862 			error = find_device(req, &dev);
5863 		break;
5864 	case DEV_FREEZE:
5865 	case DEV_THAW:
5866 		error = priv_check(td, PRIV_DRIVER);
5867 		break;
5868 	case DEV_GET_PATH:
5869 		error = find_device(req, &dev);
5870 		break;
5871 	default:
5872 		error = ENOTTY;
5873 		break;
5874 	}
5875 	if (error) {
5876 		bus_topo_unlock();
5877 		return (error);
5878 	}
5879 
5880 	/* Perform the requested operation. */
5881 	switch (cmd) {
5882 	case DEV_ATTACH:
5883 		if (device_is_attached(dev))
5884 			error = EBUSY;
5885 		else if (!device_is_enabled(dev))
5886 			error = ENXIO;
5887 		else
5888 			error = device_probe_and_attach(dev);
5889 		break;
5890 	case DEV_DETACH:
5891 		if (!device_is_attached(dev)) {
5892 			error = ENXIO;
5893 			break;
5894 		}
5895 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5896 			error = device_quiesce(dev);
5897 			if (error)
5898 				break;
5899 		}
5900 		error = device_detach(dev);
5901 		break;
5902 	case DEV_ENABLE:
5903 		if (device_is_enabled(dev)) {
5904 			error = EBUSY;
5905 			break;
5906 		}
5907 
5908 		/*
5909 		 * If the device has been probed but not attached (e.g.
5910 		 * when it has been disabled by a loader hint), just
5911 		 * attach the device rather than doing a full probe.
5912 		 */
5913 		device_enable(dev);
5914 		if (device_is_alive(dev)) {
5915 			/*
5916 			 * If the device was disabled via a hint, clear
5917 			 * the hint.
5918 			 */
5919 			if (resource_disabled(dev->driver->name, dev->unit))
5920 				resource_unset_value(dev->driver->name,
5921 				    dev->unit, "disabled");
5922 			error = device_attach(dev);
5923 		} else
5924 			error = device_probe_and_attach(dev);
5925 		break;
5926 	case DEV_DISABLE:
5927 		if (!device_is_enabled(dev)) {
5928 			error = ENXIO;
5929 			break;
5930 		}
5931 
5932 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5933 			error = device_quiesce(dev);
5934 			if (error)
5935 				break;
5936 		}
5937 
5938 		/*
5939 		 * Force DF_FIXEDCLASS on around detach to preserve
5940 		 * the existing name.
5941 		 */
5942 		old = dev->flags;
5943 		dev->flags |= DF_FIXEDCLASS;
5944 		error = device_detach(dev);
5945 		if (!(old & DF_FIXEDCLASS))
5946 			dev->flags &= ~DF_FIXEDCLASS;
5947 		if (error == 0)
5948 			device_disable(dev);
5949 		break;
5950 	case DEV_SUSPEND:
5951 		if (device_is_suspended(dev)) {
5952 			error = EBUSY;
5953 			break;
5954 		}
5955 		if (device_get_parent(dev) == NULL) {
5956 			error = EINVAL;
5957 			break;
5958 		}
5959 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5960 		break;
5961 	case DEV_RESUME:
5962 		if (!device_is_suspended(dev)) {
5963 			error = EINVAL;
5964 			break;
5965 		}
5966 		if (device_get_parent(dev) == NULL) {
5967 			error = EINVAL;
5968 			break;
5969 		}
5970 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5971 		break;
5972 	case DEV_SET_DRIVER: {
5973 		devclass_t dc;
5974 		char driver[128];
5975 
5976 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5977 		if (error)
5978 			break;
5979 		if (driver[0] == '\0') {
5980 			error = EINVAL;
5981 			break;
5982 		}
5983 		if (dev->devclass != NULL &&
5984 		    strcmp(driver, dev->devclass->name) == 0)
5985 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5986 			break;
5987 
5988 		/*
5989 		 * Scan drivers for this device's bus looking for at
5990 		 * least one matching driver.
5991 		 */
5992 		if (dev->parent == NULL) {
5993 			error = EINVAL;
5994 			break;
5995 		}
5996 		if (!driver_exists(dev->parent, driver)) {
5997 			error = ENOENT;
5998 			break;
5999 		}
6000 		dc = devclass_create(driver);
6001 		if (dc == NULL) {
6002 			error = ENOMEM;
6003 			break;
6004 		}
6005 
6006 		/* Detach device if necessary. */
6007 		if (device_is_attached(dev)) {
6008 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
6009 				error = device_detach(dev);
6010 			else
6011 				error = EBUSY;
6012 			if (error)
6013 				break;
6014 		}
6015 
6016 		/* Clear any previously-fixed device class and unit. */
6017 		if (dev->flags & DF_FIXEDCLASS)
6018 			devclass_delete_device(dev->devclass, dev);
6019 		dev->flags |= DF_WILDCARD;
6020 		dev->unit = -1;
6021 
6022 		/* Force the new device class. */
6023 		error = devclass_add_device(dc, dev);
6024 		if (error)
6025 			break;
6026 		dev->flags |= DF_FIXEDCLASS;
6027 		error = device_probe_and_attach(dev);
6028 		break;
6029 	}
6030 	case DEV_CLEAR_DRIVER:
6031 		if (!(dev->flags & DF_FIXEDCLASS)) {
6032 			error = 0;
6033 			break;
6034 		}
6035 		if (device_is_attached(dev)) {
6036 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
6037 				error = device_detach(dev);
6038 			else
6039 				error = EBUSY;
6040 			if (error)
6041 				break;
6042 		}
6043 
6044 		dev->flags &= ~DF_FIXEDCLASS;
6045 		dev->flags |= DF_WILDCARD;
6046 		devclass_delete_device(dev->devclass, dev);
6047 		error = device_probe_and_attach(dev);
6048 		break;
6049 	case DEV_RESCAN:
6050 		if (!device_is_attached(dev)) {
6051 			error = ENXIO;
6052 			break;
6053 		}
6054 		error = BUS_RESCAN(dev);
6055 		break;
6056 	case DEV_DELETE: {
6057 		device_t parent;
6058 
6059 		parent = device_get_parent(dev);
6060 		if (parent == NULL) {
6061 			error = EINVAL;
6062 			break;
6063 		}
6064 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
6065 			if (bus_child_present(dev) != 0) {
6066 				error = EBUSY;
6067 				break;
6068 			}
6069 		}
6070 
6071 		error = device_delete_child(parent, dev);
6072 		break;
6073 	}
6074 	case DEV_FREEZE:
6075 		if (device_frozen)
6076 			error = EBUSY;
6077 		else
6078 			device_frozen = true;
6079 		break;
6080 	case DEV_THAW:
6081 		if (!device_frozen)
6082 			error = EBUSY;
6083 		else {
6084 			device_do_deferred_actions();
6085 			device_frozen = false;
6086 		}
6087 		break;
6088 	case DEV_RESET:
6089 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
6090 			error = EINVAL;
6091 			break;
6092 		}
6093 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
6094 		    req->dr_flags);
6095 		break;
6096 	case DEV_GET_PATH: {
6097 		char locator[64];
6098 		char *path;
6099 		ssize_t len;
6100 
6101 		error = copyinstr(req->dr_buffer.buffer, locator, sizeof(locator), NULL);
6102 		if (error)
6103 			break;
6104 		path = device_get_path(dev, locator);
6105 		if (path == NULL) {
6106 			error = ENOMEM;
6107 			break;
6108 		}
6109 		len = strlen(path) + 1;
6110 		if (req->dr_buffer.length < len) {
6111 			error = ENAMETOOLONG;
6112 		} else {
6113 			error = copyout(path, req->dr_buffer.buffer, len);
6114 		}
6115 		req->dr_buffer.length = len;
6116 		free(path, M_BUS);
6117 		break;
6118 	}
6119 	}
6120 	bus_topo_unlock();
6121 	return (error);
6122 }
6123 
6124 static struct cdevsw devctl2_cdevsw = {
6125 	.d_version =	D_VERSION,
6126 	.d_ioctl =	devctl2_ioctl,
6127 	.d_name =	"devctl2",
6128 };
6129 
6130 static void
6131 devctl2_init(void)
6132 {
6133 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
6134 	    UID_ROOT, GID_WHEEL, 0644, "devctl2");
6135 }
6136 
6137 /*
6138  * For maintaining device 'at' location info to avoid recomputing it
6139  */
6140 struct device_location_node {
6141 	const char *dln_locator;
6142 	const char *dln_path;
6143 	TAILQ_ENTRY(device_location_node) dln_link;
6144 };
6145 typedef TAILQ_HEAD(device_location_list, device_location_node) device_location_list_t;
6146 
6147 struct device_location_cache {
6148 	device_location_list_t dlc_list;
6149 };
6150 
6151 
6152 /*
6153  * Location cache for wired devices.
6154  */
6155 device_location_cache_t *
6156 dev_wired_cache_init(void)
6157 {
6158 	device_location_cache_t *dcp;
6159 
6160 	dcp = malloc(sizeof(*dcp), M_BUS, M_WAITOK | M_ZERO);
6161 	TAILQ_INIT(&dcp->dlc_list);
6162 
6163 	return (dcp);
6164 }
6165 
6166 void
6167 dev_wired_cache_fini(device_location_cache_t *dcp)
6168 {
6169 	struct device_location_node *dln, *tdln;
6170 
6171 	TAILQ_FOREACH_SAFE(dln, &dcp->dlc_list, dln_link, tdln) {
6172 		/* Note: one allocation for both node and locator, but not path */
6173 		free(__DECONST(void *, dln->dln_path), M_BUS);
6174 		free(dln, M_BUS);
6175 	}
6176 	free(dcp, M_BUS);
6177 }
6178 
6179 static struct device_location_node *
6180 dev_wired_cache_lookup(device_location_cache_t *dcp, const char *locator)
6181 {
6182 	struct device_location_node *dln;
6183 
6184 	TAILQ_FOREACH(dln, &dcp->dlc_list, dln_link) {
6185 		if (strcmp(locator, dln->dln_locator) == 0)
6186 			return (dln);
6187 	}
6188 
6189 	return (NULL);
6190 }
6191 
6192 static struct device_location_node *
6193 dev_wired_cache_add(device_location_cache_t *dcp, const char *locator, const char *path)
6194 {
6195 	struct device_location_node *dln;
6196 	char *l;
6197 
6198 	dln = malloc(sizeof(*dln) + strlen(locator) + 1, M_BUS, M_WAITOK | M_ZERO);
6199 	dln->dln_locator = l = (char *)(dln + 1);
6200 	memcpy(l, locator, strlen(locator) + 1);
6201 	dln->dln_path = path;
6202 	TAILQ_INSERT_HEAD(&dcp->dlc_list, dln, dln_link);
6203 
6204 	return (dln);
6205 }
6206 
6207 bool
6208 dev_wired_cache_match(device_location_cache_t *dcp, device_t dev, const char *at)
6209 {
6210 	const char *cp, *path;
6211 	char locator[32];
6212 	int len;
6213 	struct device_location_node *res;
6214 
6215 	cp = strchr(at, ':');
6216 	if (cp == NULL)
6217 		return (false);
6218 	len = cp - at;
6219 	if (len > sizeof(locator) - 1)	/* Skip too long locator */
6220 		return (false);
6221 	memcpy(locator, at, len);
6222 	locator[len] = '\0';
6223 	cp++;
6224 
6225 	/* maybe cache this inside device_t and look that up, but not yet */
6226 	res = dev_wired_cache_lookup(dcp, locator);
6227 	if (res == NULL) {
6228 		path = device_get_path(dev, locator);
6229 		res = dev_wired_cache_add(dcp, locator, path);
6230 	}
6231 	if (res == NULL || res->dln_path == NULL)
6232 		return (false);
6233 
6234 	return (strcmp(res->dln_path, cp) == 0);
6235 }
6236 
6237 /*
6238  * APIs to manage deprecation and obsolescence.
6239  */
6240 static int obsolete_panic = 0;
6241 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
6242     "Panic when obsolete features are used (0 = never, 1 = if obsolete, "
6243     "2 = if deprecated)");
6244 
6245 static void
6246 gone_panic(int major, int running, const char *msg)
6247 {
6248 	switch (obsolete_panic)
6249 	{
6250 	case 0:
6251 		return;
6252 	case 1:
6253 		if (running < major)
6254 			return;
6255 		/* FALLTHROUGH */
6256 	default:
6257 		panic("%s", msg);
6258 	}
6259 }
6260 
6261 void
6262 _gone_in(int major, const char *msg)
6263 {
6264 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6265 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6266 		printf("Obsolete code will be removed soon: %s\n", msg);
6267 	else
6268 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6269 		    major, msg);
6270 }
6271 
6272 void
6273 _gone_in_dev(device_t dev, int major, const char *msg)
6274 {
6275 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6276 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6277 		device_printf(dev,
6278 		    "Obsolete code will be removed soon: %s\n", msg);
6279 	else
6280 		device_printf(dev,
6281 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6282 		    major, msg);
6283 }
6284 
6285 #ifdef DDB
6286 DB_SHOW_COMMAND(device, db_show_device)
6287 {
6288 	device_t dev;
6289 
6290 	if (!have_addr)
6291 		return;
6292 
6293 	dev = (device_t)addr;
6294 
6295 	db_printf("name:    %s\n", device_get_nameunit(dev));
6296 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6297 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6298 	db_printf("  addr:    %p\n", dev);
6299 	db_printf("  parent:  %p\n", dev->parent);
6300 	db_printf("  softc:   %p\n", dev->softc);
6301 	db_printf("  ivars:   %p\n", dev->ivars);
6302 }
6303 
6304 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6305 {
6306 	device_t dev;
6307 
6308 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6309 		db_show_device((db_expr_t)dev, true, count, modif);
6310 	}
6311 }
6312 #endif
6313