xref: /freebsd/sys/kern/subr_bus.c (revision 8bcb0991864975618c09697b1aca10683346d9f0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/rman.h>
55 #include <sys/sbuf.h>
56 #include <sys/selinfo.h>
57 #include <sys/signalvar.h>
58 #include <sys/smp.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61 #include <sys/uio.h>
62 #include <sys/bus.h>
63 #include <sys/cpuset.h>
64 
65 #include <net/vnet.h>
66 
67 #include <machine/cpu.h>
68 #include <machine/stdarg.h>
69 
70 #include <vm/uma.h>
71 #include <vm/vm.h>
72 
73 #include <ddb/ddb.h>
74 
75 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW, NULL, NULL);
76 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW, NULL, NULL);
77 
78 /*
79  * Used to attach drivers to devclasses.
80  */
81 typedef struct driverlink *driverlink_t;
82 struct driverlink {
83 	kobj_class_t	driver;
84 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
85 	int		pass;
86 	int		flags;
87 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
88 	TAILQ_ENTRY(driverlink) passlink;
89 };
90 
91 /*
92  * Forward declarations
93  */
94 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
95 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
96 typedef TAILQ_HEAD(device_list, device) device_list_t;
97 
98 struct devclass {
99 	TAILQ_ENTRY(devclass) link;
100 	devclass_t	parent;		/* parent in devclass hierarchy */
101 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
102 	char		*name;
103 	device_t	*devices;	/* array of devices indexed by unit */
104 	int		maxunit;	/* size of devices array */
105 	int		flags;
106 #define DC_HAS_CHILDREN		1
107 
108 	struct sysctl_ctx_list sysctl_ctx;
109 	struct sysctl_oid *sysctl_tree;
110 };
111 
112 /**
113  * @brief Implementation of device.
114  */
115 struct device {
116 	/*
117 	 * A device is a kernel object. The first field must be the
118 	 * current ops table for the object.
119 	 */
120 	KOBJ_FIELDS;
121 
122 	/*
123 	 * Device hierarchy.
124 	 */
125 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
126 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
127 	device_t	parent;		/**< parent of this device  */
128 	device_list_t	children;	/**< list of child devices */
129 
130 	/*
131 	 * Details of this device.
132 	 */
133 	driver_t	*driver;	/**< current driver */
134 	devclass_t	devclass;	/**< current device class */
135 	int		unit;		/**< current unit number */
136 	char*		nameunit;	/**< name+unit e.g. foodev0 */
137 	char*		desc;		/**< driver specific description */
138 	int		busy;		/**< count of calls to device_busy() */
139 	device_state_t	state;		/**< current device state  */
140 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
141 	u_int		flags;		/**< internal device flags  */
142 	u_int	order;			/**< order from device_add_child_ordered() */
143 	void	*ivars;			/**< instance variables  */
144 	void	*softc;			/**< current driver's variables  */
145 
146 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
147 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
148 };
149 
150 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
151 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
152 
153 EVENTHANDLER_LIST_DEFINE(device_attach);
154 EVENTHANDLER_LIST_DEFINE(device_detach);
155 EVENTHANDLER_LIST_DEFINE(dev_lookup);
156 
157 static void devctl2_init(void);
158 static bool device_frozen;
159 
160 #define DRIVERNAME(d)	((d)? d->name : "no driver")
161 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
162 
163 #ifdef BUS_DEBUG
164 
165 static int bus_debug = 1;
166 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
167     "Bus debug level");
168 
169 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
170 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
171 
172 /**
173  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
174  * prevent syslog from deleting initial spaces
175  */
176 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
177 
178 static void print_device_short(device_t dev, int indent);
179 static void print_device(device_t dev, int indent);
180 void print_device_tree_short(device_t dev, int indent);
181 void print_device_tree(device_t dev, int indent);
182 static void print_driver_short(driver_t *driver, int indent);
183 static void print_driver(driver_t *driver, int indent);
184 static void print_driver_list(driver_list_t drivers, int indent);
185 static void print_devclass_short(devclass_t dc, int indent);
186 static void print_devclass(devclass_t dc, int indent);
187 void print_devclass_list_short(void);
188 void print_devclass_list(void);
189 
190 #else
191 /* Make the compiler ignore the function calls */
192 #define PDEBUG(a)			/* nop */
193 #define DEVICENAME(d)			/* nop */
194 
195 #define print_device_short(d,i)		/* nop */
196 #define print_device(d,i)		/* nop */
197 #define print_device_tree_short(d,i)	/* nop */
198 #define print_device_tree(d,i)		/* nop */
199 #define print_driver_short(d,i)		/* nop */
200 #define print_driver(d,i)		/* nop */
201 #define print_driver_list(d,i)		/* nop */
202 #define print_devclass_short(d,i)	/* nop */
203 #define print_devclass(d,i)		/* nop */
204 #define print_devclass_list_short()	/* nop */
205 #define print_devclass_list()		/* nop */
206 #endif
207 
208 /*
209  * dev sysctl tree
210  */
211 
212 enum {
213 	DEVCLASS_SYSCTL_PARENT,
214 };
215 
216 static int
217 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
218 {
219 	devclass_t dc = (devclass_t)arg1;
220 	const char *value;
221 
222 	switch (arg2) {
223 	case DEVCLASS_SYSCTL_PARENT:
224 		value = dc->parent ? dc->parent->name : "";
225 		break;
226 	default:
227 		return (EINVAL);
228 	}
229 	return (SYSCTL_OUT_STR(req, value));
230 }
231 
232 static void
233 devclass_sysctl_init(devclass_t dc)
234 {
235 
236 	if (dc->sysctl_tree != NULL)
237 		return;
238 	sysctl_ctx_init(&dc->sysctl_ctx);
239 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
240 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
241 	    CTLFLAG_RD, NULL, "");
242 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
243 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
244 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
245 	    "parent class");
246 }
247 
248 enum {
249 	DEVICE_SYSCTL_DESC,
250 	DEVICE_SYSCTL_DRIVER,
251 	DEVICE_SYSCTL_LOCATION,
252 	DEVICE_SYSCTL_PNPINFO,
253 	DEVICE_SYSCTL_PARENT,
254 };
255 
256 static int
257 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
258 {
259 	device_t dev = (device_t)arg1;
260 	const char *value;
261 	char *buf;
262 	int error;
263 
264 	buf = NULL;
265 	switch (arg2) {
266 	case DEVICE_SYSCTL_DESC:
267 		value = dev->desc ? dev->desc : "";
268 		break;
269 	case DEVICE_SYSCTL_DRIVER:
270 		value = dev->driver ? dev->driver->name : "";
271 		break;
272 	case DEVICE_SYSCTL_LOCATION:
273 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
274 		bus_child_location_str(dev, buf, 1024);
275 		break;
276 	case DEVICE_SYSCTL_PNPINFO:
277 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
278 		bus_child_pnpinfo_str(dev, buf, 1024);
279 		break;
280 	case DEVICE_SYSCTL_PARENT:
281 		value = dev->parent ? dev->parent->nameunit : "";
282 		break;
283 	default:
284 		return (EINVAL);
285 	}
286 	error = SYSCTL_OUT_STR(req, value);
287 	if (buf != NULL)
288 		free(buf, M_BUS);
289 	return (error);
290 }
291 
292 static void
293 device_sysctl_init(device_t dev)
294 {
295 	devclass_t dc = dev->devclass;
296 	int domain;
297 
298 	if (dev->sysctl_tree != NULL)
299 		return;
300 	devclass_sysctl_init(dc);
301 	sysctl_ctx_init(&dev->sysctl_ctx);
302 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
303 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
304 	    dev->nameunit + strlen(dc->name),
305 	    CTLFLAG_RD, NULL, "", "device_index");
306 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
307 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD,
308 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
309 	    "device description");
310 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
311 	    OID_AUTO, "%driver", CTLTYPE_STRING | CTLFLAG_RD,
312 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
313 	    "device driver name");
314 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
315 	    OID_AUTO, "%location", CTLTYPE_STRING | CTLFLAG_RD,
316 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
317 	    "device location relative to parent");
318 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
319 	    OID_AUTO, "%pnpinfo", CTLTYPE_STRING | CTLFLAG_RD,
320 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
321 	    "device identification");
322 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
323 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
324 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
325 	    "parent device");
326 	if (bus_get_domain(dev, &domain) == 0)
327 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
328 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
329 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
330 }
331 
332 static void
333 device_sysctl_update(device_t dev)
334 {
335 	devclass_t dc = dev->devclass;
336 
337 	if (dev->sysctl_tree == NULL)
338 		return;
339 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
340 }
341 
342 static void
343 device_sysctl_fini(device_t dev)
344 {
345 	if (dev->sysctl_tree == NULL)
346 		return;
347 	sysctl_ctx_free(&dev->sysctl_ctx);
348 	dev->sysctl_tree = NULL;
349 }
350 
351 /*
352  * /dev/devctl implementation
353  */
354 
355 /*
356  * This design allows only one reader for /dev/devctl.  This is not desirable
357  * in the long run, but will get a lot of hair out of this implementation.
358  * Maybe we should make this device a clonable device.
359  *
360  * Also note: we specifically do not attach a device to the device_t tree
361  * to avoid potential chicken and egg problems.  One could argue that all
362  * of this belongs to the root node.  One could also further argue that the
363  * sysctl interface that we have not might more properly be an ioctl
364  * interface, but at this stage of the game, I'm not inclined to rock that
365  * boat.
366  *
367  * I'm also not sure that the SIGIO support is done correctly or not, as
368  * I copied it from a driver that had SIGIO support that likely hasn't been
369  * tested since 3.4 or 2.2.8!
370  */
371 
372 /* Deprecated way to adjust queue length */
373 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
374 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RWTUN |
375     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_disable, "I",
376     "devctl disable -- deprecated");
377 
378 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
379 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
380 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
381 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
382     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
383 
384 static d_open_t		devopen;
385 static d_close_t	devclose;
386 static d_read_t		devread;
387 static d_ioctl_t	devioctl;
388 static d_poll_t		devpoll;
389 static d_kqfilter_t	devkqfilter;
390 
391 static struct cdevsw dev_cdevsw = {
392 	.d_version =	D_VERSION,
393 	.d_open =	devopen,
394 	.d_close =	devclose,
395 	.d_read =	devread,
396 	.d_ioctl =	devioctl,
397 	.d_poll =	devpoll,
398 	.d_kqfilter =	devkqfilter,
399 	.d_name =	"devctl",
400 };
401 
402 struct dev_event_info
403 {
404 	char *dei_data;
405 	TAILQ_ENTRY(dev_event_info) dei_link;
406 };
407 
408 TAILQ_HEAD(devq, dev_event_info);
409 
410 static struct dev_softc
411 {
412 	int	inuse;
413 	int	nonblock;
414 	int	queued;
415 	int	async;
416 	struct mtx mtx;
417 	struct cv cv;
418 	struct selinfo sel;
419 	struct devq devq;
420 	struct sigio *sigio;
421 } devsoftc;
422 
423 static void	filt_devctl_detach(struct knote *kn);
424 static int	filt_devctl_read(struct knote *kn, long hint);
425 
426 struct filterops devctl_rfiltops = {
427 	.f_isfd = 1,
428 	.f_detach = filt_devctl_detach,
429 	.f_event = filt_devctl_read,
430 };
431 
432 static struct cdev *devctl_dev;
433 
434 static void
435 devinit(void)
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 	TAILQ_INIT(&devsoftc.devq);
442 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
443 	devctl2_init();
444 }
445 
446 static int
447 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
448 {
449 
450 	mtx_lock(&devsoftc.mtx);
451 	if (devsoftc.inuse) {
452 		mtx_unlock(&devsoftc.mtx);
453 		return (EBUSY);
454 	}
455 	/* move to init */
456 	devsoftc.inuse = 1;
457 	mtx_unlock(&devsoftc.mtx);
458 	return (0);
459 }
460 
461 static int
462 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
463 {
464 
465 	mtx_lock(&devsoftc.mtx);
466 	devsoftc.inuse = 0;
467 	devsoftc.nonblock = 0;
468 	devsoftc.async = 0;
469 	cv_broadcast(&devsoftc.cv);
470 	funsetown(&devsoftc.sigio);
471 	mtx_unlock(&devsoftc.mtx);
472 	return (0);
473 }
474 
475 /*
476  * The read channel for this device is used to report changes to
477  * userland in realtime.  We are required to free the data as well as
478  * the n1 object because we allocate them separately.  Also note that
479  * we return one record at a time.  If you try to read this device a
480  * character at a time, you will lose the rest of the data.  Listening
481  * programs are expected to cope.
482  */
483 static int
484 devread(struct cdev *dev, struct uio *uio, int ioflag)
485 {
486 	struct dev_event_info *n1;
487 	int rv;
488 
489 	mtx_lock(&devsoftc.mtx);
490 	while (TAILQ_EMPTY(&devsoftc.devq)) {
491 		if (devsoftc.nonblock) {
492 			mtx_unlock(&devsoftc.mtx);
493 			return (EAGAIN);
494 		}
495 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
496 		if (rv) {
497 			/*
498 			 * Need to translate ERESTART to EINTR here? -- jake
499 			 */
500 			mtx_unlock(&devsoftc.mtx);
501 			return (rv);
502 		}
503 	}
504 	n1 = TAILQ_FIRST(&devsoftc.devq);
505 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
506 	devsoftc.queued--;
507 	mtx_unlock(&devsoftc.mtx);
508 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
509 	free(n1->dei_data, M_BUS);
510 	free(n1, M_BUS);
511 	return (rv);
512 }
513 
514 static	int
515 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
516 {
517 	switch (cmd) {
518 
519 	case FIONBIO:
520 		if (*(int*)data)
521 			devsoftc.nonblock = 1;
522 		else
523 			devsoftc.nonblock = 0;
524 		return (0);
525 	case FIOASYNC:
526 		if (*(int*)data)
527 			devsoftc.async = 1;
528 		else
529 			devsoftc.async = 0;
530 		return (0);
531 	case FIOSETOWN:
532 		return fsetown(*(int *)data, &devsoftc.sigio);
533 	case FIOGETOWN:
534 		*(int *)data = fgetown(&devsoftc.sigio);
535 		return (0);
536 
537 		/* (un)Support for other fcntl() calls. */
538 	case FIOCLEX:
539 	case FIONCLEX:
540 	case FIONREAD:
541 	default:
542 		break;
543 	}
544 	return (ENOTTY);
545 }
546 
547 static	int
548 devpoll(struct cdev *dev, int events, struct thread *td)
549 {
550 	int	revents = 0;
551 
552 	mtx_lock(&devsoftc.mtx);
553 	if (events & (POLLIN | POLLRDNORM)) {
554 		if (!TAILQ_EMPTY(&devsoftc.devq))
555 			revents = events & (POLLIN | POLLRDNORM);
556 		else
557 			selrecord(td, &devsoftc.sel);
558 	}
559 	mtx_unlock(&devsoftc.mtx);
560 
561 	return (revents);
562 }
563 
564 static int
565 devkqfilter(struct cdev *dev, struct knote *kn)
566 {
567 	int error;
568 
569 	if (kn->kn_filter == EVFILT_READ) {
570 		kn->kn_fop = &devctl_rfiltops;
571 		knlist_add(&devsoftc.sel.si_note, kn, 0);
572 		error = 0;
573 	} else
574 		error = EINVAL;
575 	return (error);
576 }
577 
578 static void
579 filt_devctl_detach(struct knote *kn)
580 {
581 
582 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
583 }
584 
585 static int
586 filt_devctl_read(struct knote *kn, long hint)
587 {
588 	kn->kn_data = devsoftc.queued;
589 	return (kn->kn_data != 0);
590 }
591 
592 /**
593  * @brief Return whether the userland process is running
594  */
595 boolean_t
596 devctl_process_running(void)
597 {
598 	return (devsoftc.inuse == 1);
599 }
600 
601 /**
602  * @brief Queue data to be read from the devctl device
603  *
604  * Generic interface to queue data to the devctl device.  It is
605  * assumed that @p data is properly formatted.  It is further assumed
606  * that @p data is allocated using the M_BUS malloc type.
607  */
608 void
609 devctl_queue_data_f(char *data, int flags)
610 {
611 	struct dev_event_info *n1 = NULL, *n2 = NULL;
612 
613 	if (strlen(data) == 0)
614 		goto out;
615 	if (devctl_queue_length == 0)
616 		goto out;
617 	n1 = malloc(sizeof(*n1), M_BUS, flags);
618 	if (n1 == NULL)
619 		goto out;
620 	n1->dei_data = data;
621 	mtx_lock(&devsoftc.mtx);
622 	if (devctl_queue_length == 0) {
623 		mtx_unlock(&devsoftc.mtx);
624 		free(n1->dei_data, M_BUS);
625 		free(n1, M_BUS);
626 		return;
627 	}
628 	/* Leave at least one spot in the queue... */
629 	while (devsoftc.queued > devctl_queue_length - 1) {
630 		n2 = TAILQ_FIRST(&devsoftc.devq);
631 		TAILQ_REMOVE(&devsoftc.devq, n2, dei_link);
632 		free(n2->dei_data, M_BUS);
633 		free(n2, M_BUS);
634 		devsoftc.queued--;
635 	}
636 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
637 	devsoftc.queued++;
638 	cv_broadcast(&devsoftc.cv);
639 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
640 	mtx_unlock(&devsoftc.mtx);
641 	selwakeup(&devsoftc.sel);
642 	if (devsoftc.async && devsoftc.sigio != NULL)
643 		pgsigio(&devsoftc.sigio, SIGIO, 0);
644 	return;
645 out:
646 	/*
647 	 * We have to free data on all error paths since the caller
648 	 * assumes it will be free'd when this item is dequeued.
649 	 */
650 	free(data, M_BUS);
651 	return;
652 }
653 
654 void
655 devctl_queue_data(char *data)
656 {
657 
658 	devctl_queue_data_f(data, M_NOWAIT);
659 }
660 
661 /**
662  * @brief Send a 'notification' to userland, using standard ways
663  */
664 void
665 devctl_notify_f(const char *system, const char *subsystem, const char *type,
666     const char *data, int flags)
667 {
668 	int len = 0;
669 	char *msg;
670 
671 	if (system == NULL)
672 		return;		/* BOGUS!  Must specify system. */
673 	if (subsystem == NULL)
674 		return;		/* BOGUS!  Must specify subsystem. */
675 	if (type == NULL)
676 		return;		/* BOGUS!  Must specify type. */
677 	len += strlen(" system=") + strlen(system);
678 	len += strlen(" subsystem=") + strlen(subsystem);
679 	len += strlen(" type=") + strlen(type);
680 	/* add in the data message plus newline. */
681 	if (data != NULL)
682 		len += strlen(data);
683 	len += 3;	/* '!', '\n', and NUL */
684 	msg = malloc(len, M_BUS, flags);
685 	if (msg == NULL)
686 		return;		/* Drop it on the floor */
687 	if (data != NULL)
688 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
689 		    system, subsystem, type, data);
690 	else
691 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
692 		    system, subsystem, type);
693 	devctl_queue_data_f(msg, flags);
694 }
695 
696 void
697 devctl_notify(const char *system, const char *subsystem, const char *type,
698     const char *data)
699 {
700 
701 	devctl_notify_f(system, subsystem, type, data, M_NOWAIT);
702 }
703 
704 /*
705  * Common routine that tries to make sending messages as easy as possible.
706  * We allocate memory for the data, copy strings into that, but do not
707  * free it unless there's an error.  The dequeue part of the driver should
708  * free the data.  We don't send data when the device is disabled.  We do
709  * send data, even when we have no listeners, because we wish to avoid
710  * races relating to startup and restart of listening applications.
711  *
712  * devaddq is designed to string together the type of event, with the
713  * object of that event, plus the plug and play info and location info
714  * for that event.  This is likely most useful for devices, but less
715  * useful for other consumers of this interface.  Those should use
716  * the devctl_queue_data() interface instead.
717  */
718 static void
719 devaddq(const char *type, const char *what, device_t dev)
720 {
721 	char *data = NULL;
722 	char *loc = NULL;
723 	char *pnp = NULL;
724 	const char *parstr;
725 
726 	if (!devctl_queue_length)/* Rare race, but lost races safely discard */
727 		return;
728 	data = malloc(1024, M_BUS, M_NOWAIT);
729 	if (data == NULL)
730 		goto bad;
731 
732 	/* get the bus specific location of this device */
733 	loc = malloc(1024, M_BUS, M_NOWAIT);
734 	if (loc == NULL)
735 		goto bad;
736 	*loc = '\0';
737 	bus_child_location_str(dev, loc, 1024);
738 
739 	/* Get the bus specific pnp info of this device */
740 	pnp = malloc(1024, M_BUS, M_NOWAIT);
741 	if (pnp == NULL)
742 		goto bad;
743 	*pnp = '\0';
744 	bus_child_pnpinfo_str(dev, pnp, 1024);
745 
746 	/* Get the parent of this device, or / if high enough in the tree. */
747 	if (device_get_parent(dev) == NULL)
748 		parstr = ".";	/* Or '/' ? */
749 	else
750 		parstr = device_get_nameunit(device_get_parent(dev));
751 	/* String it all together. */
752 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
753 	  parstr);
754 	free(loc, M_BUS);
755 	free(pnp, M_BUS);
756 	devctl_queue_data(data);
757 	return;
758 bad:
759 	free(pnp, M_BUS);
760 	free(loc, M_BUS);
761 	free(data, M_BUS);
762 	return;
763 }
764 
765 /*
766  * A device was added to the tree.  We are called just after it successfully
767  * attaches (that is, probe and attach success for this device).  No call
768  * is made if a device is merely parented into the tree.  See devnomatch
769  * if probe fails.  If attach fails, no notification is sent (but maybe
770  * we should have a different message for this).
771  */
772 static void
773 devadded(device_t dev)
774 {
775 	devaddq("+", device_get_nameunit(dev), dev);
776 }
777 
778 /*
779  * A device was removed from the tree.  We are called just before this
780  * happens.
781  */
782 static void
783 devremoved(device_t dev)
784 {
785 	devaddq("-", device_get_nameunit(dev), dev);
786 }
787 
788 /*
789  * Called when there's no match for this device.  This is only called
790  * the first time that no match happens, so we don't keep getting this
791  * message.  Should that prove to be undesirable, we can change it.
792  * This is called when all drivers that can attach to a given bus
793  * decline to accept this device.  Other errors may not be detected.
794  */
795 static void
796 devnomatch(device_t dev)
797 {
798 	devaddq("?", "", dev);
799 }
800 
801 static int
802 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
803 {
804 	struct dev_event_info *n1;
805 	int dis, error;
806 
807 	dis = (devctl_queue_length == 0);
808 	error = sysctl_handle_int(oidp, &dis, 0, req);
809 	if (error || !req->newptr)
810 		return (error);
811 	if (mtx_initialized(&devsoftc.mtx))
812 		mtx_lock(&devsoftc.mtx);
813 	if (dis) {
814 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
815 			n1 = TAILQ_FIRST(&devsoftc.devq);
816 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
817 			free(n1->dei_data, M_BUS);
818 			free(n1, M_BUS);
819 		}
820 		devsoftc.queued = 0;
821 		devctl_queue_length = 0;
822 	} else {
823 		devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
824 	}
825 	if (mtx_initialized(&devsoftc.mtx))
826 		mtx_unlock(&devsoftc.mtx);
827 	return (0);
828 }
829 
830 static int
831 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
832 {
833 	struct dev_event_info *n1;
834 	int q, error;
835 
836 	q = devctl_queue_length;
837 	error = sysctl_handle_int(oidp, &q, 0, req);
838 	if (error || !req->newptr)
839 		return (error);
840 	if (q < 0)
841 		return (EINVAL);
842 	if (mtx_initialized(&devsoftc.mtx))
843 		mtx_lock(&devsoftc.mtx);
844 	devctl_queue_length = q;
845 	while (devsoftc.queued > devctl_queue_length) {
846 		n1 = TAILQ_FIRST(&devsoftc.devq);
847 		TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
848 		free(n1->dei_data, M_BUS);
849 		free(n1, M_BUS);
850 		devsoftc.queued--;
851 	}
852 	if (mtx_initialized(&devsoftc.mtx))
853 		mtx_unlock(&devsoftc.mtx);
854 	return (0);
855 }
856 
857 /**
858  * @brief safely quotes strings that might have double quotes in them.
859  *
860  * The devctl protocol relies on quoted strings having matching quotes.
861  * This routine quotes any internal quotes so the resulting string
862  * is safe to pass to snprintf to construct, for example pnp info strings.
863  * Strings are always terminated with a NUL, but may be truncated if longer
864  * than @p len bytes after quotes.
865  *
866  * @param sb	sbuf to place the characters into
867  * @param src	Original buffer.
868  */
869 void
870 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
871 {
872 
873 	while (*src != '\0') {
874 		if (*src == '"' || *src == '\\')
875 			sbuf_putc(sb, '\\');
876 		sbuf_putc(sb, *src++);
877 	}
878 }
879 
880 /* End of /dev/devctl code */
881 
882 static TAILQ_HEAD(,device)	bus_data_devices;
883 static int bus_data_generation = 1;
884 
885 static kobj_method_t null_methods[] = {
886 	KOBJMETHOD_END
887 };
888 
889 DEFINE_CLASS(null, null_methods, 0);
890 
891 /*
892  * Bus pass implementation
893  */
894 
895 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
896 int bus_current_pass = BUS_PASS_ROOT;
897 
898 /**
899  * @internal
900  * @brief Register the pass level of a new driver attachment
901  *
902  * Register a new driver attachment's pass level.  If no driver
903  * attachment with the same pass level has been added, then @p new
904  * will be added to the global passes list.
905  *
906  * @param new		the new driver attachment
907  */
908 static void
909 driver_register_pass(struct driverlink *new)
910 {
911 	struct driverlink *dl;
912 
913 	/* We only consider pass numbers during boot. */
914 	if (bus_current_pass == BUS_PASS_DEFAULT)
915 		return;
916 
917 	/*
918 	 * Walk the passes list.  If we already know about this pass
919 	 * then there is nothing to do.  If we don't, then insert this
920 	 * driver link into the list.
921 	 */
922 	TAILQ_FOREACH(dl, &passes, passlink) {
923 		if (dl->pass < new->pass)
924 			continue;
925 		if (dl->pass == new->pass)
926 			return;
927 		TAILQ_INSERT_BEFORE(dl, new, passlink);
928 		return;
929 	}
930 	TAILQ_INSERT_TAIL(&passes, new, passlink);
931 }
932 
933 /**
934  * @brief Raise the current bus pass
935  *
936  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
937  * method on the root bus to kick off a new device tree scan for each
938  * new pass level that has at least one driver.
939  */
940 void
941 bus_set_pass(int pass)
942 {
943 	struct driverlink *dl;
944 
945 	if (bus_current_pass > pass)
946 		panic("Attempt to lower bus pass level");
947 
948 	TAILQ_FOREACH(dl, &passes, passlink) {
949 		/* Skip pass values below the current pass level. */
950 		if (dl->pass <= bus_current_pass)
951 			continue;
952 
953 		/*
954 		 * Bail once we hit a driver with a pass level that is
955 		 * too high.
956 		 */
957 		if (dl->pass > pass)
958 			break;
959 
960 		/*
961 		 * Raise the pass level to the next level and rescan
962 		 * the tree.
963 		 */
964 		bus_current_pass = dl->pass;
965 		BUS_NEW_PASS(root_bus);
966 	}
967 
968 	/*
969 	 * If there isn't a driver registered for the requested pass,
970 	 * then bus_current_pass might still be less than 'pass'.  Set
971 	 * it to 'pass' in that case.
972 	 */
973 	if (bus_current_pass < pass)
974 		bus_current_pass = pass;
975 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
976 }
977 
978 /*
979  * Devclass implementation
980  */
981 
982 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
983 
984 /**
985  * @internal
986  * @brief Find or create a device class
987  *
988  * If a device class with the name @p classname exists, return it,
989  * otherwise if @p create is non-zero create and return a new device
990  * class.
991  *
992  * If @p parentname is non-NULL, the parent of the devclass is set to
993  * the devclass of that name.
994  *
995  * @param classname	the devclass name to find or create
996  * @param parentname	the parent devclass name or @c NULL
997  * @param create	non-zero to create a devclass
998  */
999 static devclass_t
1000 devclass_find_internal(const char *classname, const char *parentname,
1001 		       int create)
1002 {
1003 	devclass_t dc;
1004 
1005 	PDEBUG(("looking for %s", classname));
1006 	if (!classname)
1007 		return (NULL);
1008 
1009 	TAILQ_FOREACH(dc, &devclasses, link) {
1010 		if (!strcmp(dc->name, classname))
1011 			break;
1012 	}
1013 
1014 	if (create && !dc) {
1015 		PDEBUG(("creating %s", classname));
1016 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1017 		    M_BUS, M_NOWAIT | M_ZERO);
1018 		if (!dc)
1019 			return (NULL);
1020 		dc->parent = NULL;
1021 		dc->name = (char*) (dc + 1);
1022 		strcpy(dc->name, classname);
1023 		TAILQ_INIT(&dc->drivers);
1024 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1025 
1026 		bus_data_generation_update();
1027 	}
1028 
1029 	/*
1030 	 * If a parent class is specified, then set that as our parent so
1031 	 * that this devclass will support drivers for the parent class as
1032 	 * well.  If the parent class has the same name don't do this though
1033 	 * as it creates a cycle that can trigger an infinite loop in
1034 	 * device_probe_child() if a device exists for which there is no
1035 	 * suitable driver.
1036 	 */
1037 	if (parentname && dc && !dc->parent &&
1038 	    strcmp(classname, parentname) != 0) {
1039 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1040 		dc->parent->flags |= DC_HAS_CHILDREN;
1041 	}
1042 
1043 	return (dc);
1044 }
1045 
1046 /**
1047  * @brief Create a device class
1048  *
1049  * If a device class with the name @p classname exists, return it,
1050  * otherwise create and return a new device class.
1051  *
1052  * @param classname	the devclass name to find or create
1053  */
1054 devclass_t
1055 devclass_create(const char *classname)
1056 {
1057 	return (devclass_find_internal(classname, NULL, TRUE));
1058 }
1059 
1060 /**
1061  * @brief Find a device class
1062  *
1063  * If a device class with the name @p classname exists, return it,
1064  * otherwise return @c NULL.
1065  *
1066  * @param classname	the devclass name to find
1067  */
1068 devclass_t
1069 devclass_find(const char *classname)
1070 {
1071 	return (devclass_find_internal(classname, NULL, FALSE));
1072 }
1073 
1074 /**
1075  * @brief Register that a device driver has been added to a devclass
1076  *
1077  * Register that a device driver has been added to a devclass.  This
1078  * is called by devclass_add_driver to accomplish the recursive
1079  * notification of all the children classes of dc, as well as dc.
1080  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1081  * the devclass.
1082  *
1083  * We do a full search here of the devclass list at each iteration
1084  * level to save storing children-lists in the devclass structure.  If
1085  * we ever move beyond a few dozen devices doing this, we may need to
1086  * reevaluate...
1087  *
1088  * @param dc		the devclass to edit
1089  * @param driver	the driver that was just added
1090  */
1091 static void
1092 devclass_driver_added(devclass_t dc, driver_t *driver)
1093 {
1094 	devclass_t parent;
1095 	int i;
1096 
1097 	/*
1098 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1099 	 */
1100 	for (i = 0; i < dc->maxunit; i++)
1101 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1102 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1103 
1104 	/*
1105 	 * Walk through the children classes.  Since we only keep a
1106 	 * single parent pointer around, we walk the entire list of
1107 	 * devclasses looking for children.  We set the
1108 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1109 	 * the parent, so we only walk the list for those devclasses
1110 	 * that have children.
1111 	 */
1112 	if (!(dc->flags & DC_HAS_CHILDREN))
1113 		return;
1114 	parent = dc;
1115 	TAILQ_FOREACH(dc, &devclasses, link) {
1116 		if (dc->parent == parent)
1117 			devclass_driver_added(dc, driver);
1118 	}
1119 }
1120 
1121 /**
1122  * @brief Add a device driver to a device class
1123  *
1124  * Add a device driver to a devclass. This is normally called
1125  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1126  * all devices in the devclass will be called to allow them to attempt
1127  * to re-probe any unmatched children.
1128  *
1129  * @param dc		the devclass to edit
1130  * @param driver	the driver to register
1131  */
1132 int
1133 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1134 {
1135 	driverlink_t dl;
1136 	const char *parentname;
1137 
1138 	PDEBUG(("%s", DRIVERNAME(driver)));
1139 
1140 	/* Don't allow invalid pass values. */
1141 	if (pass <= BUS_PASS_ROOT)
1142 		return (EINVAL);
1143 
1144 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1145 	if (!dl)
1146 		return (ENOMEM);
1147 
1148 	/*
1149 	 * Compile the driver's methods. Also increase the reference count
1150 	 * so that the class doesn't get freed when the last instance
1151 	 * goes. This means we can safely use static methods and avoids a
1152 	 * double-free in devclass_delete_driver.
1153 	 */
1154 	kobj_class_compile((kobj_class_t) driver);
1155 
1156 	/*
1157 	 * If the driver has any base classes, make the
1158 	 * devclass inherit from the devclass of the driver's
1159 	 * first base class. This will allow the system to
1160 	 * search for drivers in both devclasses for children
1161 	 * of a device using this driver.
1162 	 */
1163 	if (driver->baseclasses)
1164 		parentname = driver->baseclasses[0]->name;
1165 	else
1166 		parentname = NULL;
1167 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1168 
1169 	dl->driver = driver;
1170 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1171 	driver->refs++;		/* XXX: kobj_mtx */
1172 	dl->pass = pass;
1173 	driver_register_pass(dl);
1174 
1175 	if (device_frozen) {
1176 		dl->flags |= DL_DEFERRED_PROBE;
1177 	} else {
1178 		devclass_driver_added(dc, driver);
1179 	}
1180 	bus_data_generation_update();
1181 	return (0);
1182 }
1183 
1184 /**
1185  * @brief Register that a device driver has been deleted from a devclass
1186  *
1187  * Register that a device driver has been removed from a devclass.
1188  * This is called by devclass_delete_driver to accomplish the
1189  * recursive notification of all the children classes of busclass, as
1190  * well as busclass.  Each layer will attempt to detach the driver
1191  * from any devices that are children of the bus's devclass.  The function
1192  * will return an error if a device fails to detach.
1193  *
1194  * We do a full search here of the devclass list at each iteration
1195  * level to save storing children-lists in the devclass structure.  If
1196  * we ever move beyond a few dozen devices doing this, we may need to
1197  * reevaluate...
1198  *
1199  * @param busclass	the devclass of the parent bus
1200  * @param dc		the devclass of the driver being deleted
1201  * @param driver	the driver being deleted
1202  */
1203 static int
1204 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1205 {
1206 	devclass_t parent;
1207 	device_t dev;
1208 	int error, i;
1209 
1210 	/*
1211 	 * Disassociate from any devices.  We iterate through all the
1212 	 * devices in the devclass of the driver and detach any which are
1213 	 * using the driver and which have a parent in the devclass which
1214 	 * we are deleting from.
1215 	 *
1216 	 * Note that since a driver can be in multiple devclasses, we
1217 	 * should not detach devices which are not children of devices in
1218 	 * the affected devclass.
1219 	 *
1220 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1221 	 * generate later.
1222 	 */
1223 	for (i = 0; i < dc->maxunit; i++) {
1224 		if (dc->devices[i]) {
1225 			dev = dc->devices[i];
1226 			if (dev->driver == driver && dev->parent &&
1227 			    dev->parent->devclass == busclass) {
1228 				if ((error = device_detach(dev)) != 0)
1229 					return (error);
1230 				if (device_frozen) {
1231 					dev->flags &= ~DF_DONENOMATCH;
1232 					dev->flags |= DF_NEEDNOMATCH;
1233 				} else {
1234 					BUS_PROBE_NOMATCH(dev->parent, dev);
1235 					devnomatch(dev);
1236 					dev->flags |= DF_DONENOMATCH;
1237 				}
1238 			}
1239 		}
1240 	}
1241 
1242 	/*
1243 	 * Walk through the children classes.  Since we only keep a
1244 	 * single parent pointer around, we walk the entire list of
1245 	 * devclasses looking for children.  We set the
1246 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1247 	 * the parent, so we only walk the list for those devclasses
1248 	 * that have children.
1249 	 */
1250 	if (!(busclass->flags & DC_HAS_CHILDREN))
1251 		return (0);
1252 	parent = busclass;
1253 	TAILQ_FOREACH(busclass, &devclasses, link) {
1254 		if (busclass->parent == parent) {
1255 			error = devclass_driver_deleted(busclass, dc, driver);
1256 			if (error)
1257 				return (error);
1258 		}
1259 	}
1260 	return (0);
1261 }
1262 
1263 /**
1264  * @brief Delete a device driver from a device class
1265  *
1266  * Delete a device driver from a devclass. This is normally called
1267  * automatically by DRIVER_MODULE().
1268  *
1269  * If the driver is currently attached to any devices,
1270  * devclass_delete_driver() will first attempt to detach from each
1271  * device. If one of the detach calls fails, the driver will not be
1272  * deleted.
1273  *
1274  * @param dc		the devclass to edit
1275  * @param driver	the driver to unregister
1276  */
1277 int
1278 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1279 {
1280 	devclass_t dc = devclass_find(driver->name);
1281 	driverlink_t dl;
1282 	int error;
1283 
1284 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1285 
1286 	if (!dc)
1287 		return (0);
1288 
1289 	/*
1290 	 * Find the link structure in the bus' list of drivers.
1291 	 */
1292 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1293 		if (dl->driver == driver)
1294 			break;
1295 	}
1296 
1297 	if (!dl) {
1298 		PDEBUG(("%s not found in %s list", driver->name,
1299 		    busclass->name));
1300 		return (ENOENT);
1301 	}
1302 
1303 	error = devclass_driver_deleted(busclass, dc, driver);
1304 	if (error != 0)
1305 		return (error);
1306 
1307 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1308 	free(dl, M_BUS);
1309 
1310 	/* XXX: kobj_mtx */
1311 	driver->refs--;
1312 	if (driver->refs == 0)
1313 		kobj_class_free((kobj_class_t) driver);
1314 
1315 	bus_data_generation_update();
1316 	return (0);
1317 }
1318 
1319 /**
1320  * @brief Quiesces a set of device drivers from a device class
1321  *
1322  * Quiesce a device driver from a devclass. This is normally called
1323  * automatically by DRIVER_MODULE().
1324  *
1325  * If the driver is currently attached to any devices,
1326  * devclass_quiesece_driver() will first attempt to quiesce each
1327  * device.
1328  *
1329  * @param dc		the devclass to edit
1330  * @param driver	the driver to unregister
1331  */
1332 static int
1333 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1334 {
1335 	devclass_t dc = devclass_find(driver->name);
1336 	driverlink_t dl;
1337 	device_t dev;
1338 	int i;
1339 	int error;
1340 
1341 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1342 
1343 	if (!dc)
1344 		return (0);
1345 
1346 	/*
1347 	 * Find the link structure in the bus' list of drivers.
1348 	 */
1349 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1350 		if (dl->driver == driver)
1351 			break;
1352 	}
1353 
1354 	if (!dl) {
1355 		PDEBUG(("%s not found in %s list", driver->name,
1356 		    busclass->name));
1357 		return (ENOENT);
1358 	}
1359 
1360 	/*
1361 	 * Quiesce all devices.  We iterate through all the devices in
1362 	 * the devclass of the driver and quiesce any which are using
1363 	 * the driver and which have a parent in the devclass which we
1364 	 * are quiescing.
1365 	 *
1366 	 * Note that since a driver can be in multiple devclasses, we
1367 	 * should not quiesce devices which are not children of
1368 	 * devices in the affected devclass.
1369 	 */
1370 	for (i = 0; i < dc->maxunit; i++) {
1371 		if (dc->devices[i]) {
1372 			dev = dc->devices[i];
1373 			if (dev->driver == driver && dev->parent &&
1374 			    dev->parent->devclass == busclass) {
1375 				if ((error = device_quiesce(dev)) != 0)
1376 					return (error);
1377 			}
1378 		}
1379 	}
1380 
1381 	return (0);
1382 }
1383 
1384 /**
1385  * @internal
1386  */
1387 static driverlink_t
1388 devclass_find_driver_internal(devclass_t dc, const char *classname)
1389 {
1390 	driverlink_t dl;
1391 
1392 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1393 
1394 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1395 		if (!strcmp(dl->driver->name, classname))
1396 			return (dl);
1397 	}
1398 
1399 	PDEBUG(("not found"));
1400 	return (NULL);
1401 }
1402 
1403 /**
1404  * @brief Return the name of the devclass
1405  */
1406 const char *
1407 devclass_get_name(devclass_t dc)
1408 {
1409 	return (dc->name);
1410 }
1411 
1412 /**
1413  * @brief Find a device given a unit number
1414  *
1415  * @param dc		the devclass to search
1416  * @param unit		the unit number to search for
1417  *
1418  * @returns		the device with the given unit number or @c
1419  *			NULL if there is no such device
1420  */
1421 device_t
1422 devclass_get_device(devclass_t dc, int unit)
1423 {
1424 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1425 		return (NULL);
1426 	return (dc->devices[unit]);
1427 }
1428 
1429 /**
1430  * @brief Find the softc field of a device given a unit number
1431  *
1432  * @param dc		the devclass to search
1433  * @param unit		the unit number to search for
1434  *
1435  * @returns		the softc field of the device with the given
1436  *			unit number or @c NULL if there is no such
1437  *			device
1438  */
1439 void *
1440 devclass_get_softc(devclass_t dc, int unit)
1441 {
1442 	device_t dev;
1443 
1444 	dev = devclass_get_device(dc, unit);
1445 	if (!dev)
1446 		return (NULL);
1447 
1448 	return (device_get_softc(dev));
1449 }
1450 
1451 /**
1452  * @brief Get a list of devices in the devclass
1453  *
1454  * An array containing a list of all the devices in the given devclass
1455  * is allocated and returned in @p *devlistp. The number of devices
1456  * in the array is returned in @p *devcountp. The caller should free
1457  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1458  *
1459  * @param dc		the devclass to examine
1460  * @param devlistp	points at location for array pointer return
1461  *			value
1462  * @param devcountp	points at location for array size return value
1463  *
1464  * @retval 0		success
1465  * @retval ENOMEM	the array allocation failed
1466  */
1467 int
1468 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1469 {
1470 	int count, i;
1471 	device_t *list;
1472 
1473 	count = devclass_get_count(dc);
1474 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1475 	if (!list)
1476 		return (ENOMEM);
1477 
1478 	count = 0;
1479 	for (i = 0; i < dc->maxunit; i++) {
1480 		if (dc->devices[i]) {
1481 			list[count] = dc->devices[i];
1482 			count++;
1483 		}
1484 	}
1485 
1486 	*devlistp = list;
1487 	*devcountp = count;
1488 
1489 	return (0);
1490 }
1491 
1492 /**
1493  * @brief Get a list of drivers in the devclass
1494  *
1495  * An array containing a list of pointers to all the drivers in the
1496  * given devclass is allocated and returned in @p *listp.  The number
1497  * of drivers in the array is returned in @p *countp. The caller should
1498  * free the array using @c free(p, M_TEMP).
1499  *
1500  * @param dc		the devclass to examine
1501  * @param listp		gives location for array pointer return value
1502  * @param countp	gives location for number of array elements
1503  *			return value
1504  *
1505  * @retval 0		success
1506  * @retval ENOMEM	the array allocation failed
1507  */
1508 int
1509 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1510 {
1511 	driverlink_t dl;
1512 	driver_t **list;
1513 	int count;
1514 
1515 	count = 0;
1516 	TAILQ_FOREACH(dl, &dc->drivers, link)
1517 		count++;
1518 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1519 	if (list == NULL)
1520 		return (ENOMEM);
1521 
1522 	count = 0;
1523 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1524 		list[count] = dl->driver;
1525 		count++;
1526 	}
1527 	*listp = list;
1528 	*countp = count;
1529 
1530 	return (0);
1531 }
1532 
1533 /**
1534  * @brief Get the number of devices in a devclass
1535  *
1536  * @param dc		the devclass to examine
1537  */
1538 int
1539 devclass_get_count(devclass_t dc)
1540 {
1541 	int count, i;
1542 
1543 	count = 0;
1544 	for (i = 0; i < dc->maxunit; i++)
1545 		if (dc->devices[i])
1546 			count++;
1547 	return (count);
1548 }
1549 
1550 /**
1551  * @brief Get the maximum unit number used in a devclass
1552  *
1553  * Note that this is one greater than the highest currently-allocated
1554  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1555  * that not even the devclass has been allocated yet.
1556  *
1557  * @param dc		the devclass to examine
1558  */
1559 int
1560 devclass_get_maxunit(devclass_t dc)
1561 {
1562 	if (dc == NULL)
1563 		return (-1);
1564 	return (dc->maxunit);
1565 }
1566 
1567 /**
1568  * @brief Find a free unit number in a devclass
1569  *
1570  * This function searches for the first unused unit number greater
1571  * that or equal to @p unit.
1572  *
1573  * @param dc		the devclass to examine
1574  * @param unit		the first unit number to check
1575  */
1576 int
1577 devclass_find_free_unit(devclass_t dc, int unit)
1578 {
1579 	if (dc == NULL)
1580 		return (unit);
1581 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1582 		unit++;
1583 	return (unit);
1584 }
1585 
1586 /**
1587  * @brief Set the parent of a devclass
1588  *
1589  * The parent class is normally initialised automatically by
1590  * DRIVER_MODULE().
1591  *
1592  * @param dc		the devclass to edit
1593  * @param pdc		the new parent devclass
1594  */
1595 void
1596 devclass_set_parent(devclass_t dc, devclass_t pdc)
1597 {
1598 	dc->parent = pdc;
1599 }
1600 
1601 /**
1602  * @brief Get the parent of a devclass
1603  *
1604  * @param dc		the devclass to examine
1605  */
1606 devclass_t
1607 devclass_get_parent(devclass_t dc)
1608 {
1609 	return (dc->parent);
1610 }
1611 
1612 struct sysctl_ctx_list *
1613 devclass_get_sysctl_ctx(devclass_t dc)
1614 {
1615 	return (&dc->sysctl_ctx);
1616 }
1617 
1618 struct sysctl_oid *
1619 devclass_get_sysctl_tree(devclass_t dc)
1620 {
1621 	return (dc->sysctl_tree);
1622 }
1623 
1624 /**
1625  * @internal
1626  * @brief Allocate a unit number
1627  *
1628  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1629  * will do). The allocated unit number is returned in @p *unitp.
1630 
1631  * @param dc		the devclass to allocate from
1632  * @param unitp		points at the location for the allocated unit
1633  *			number
1634  *
1635  * @retval 0		success
1636  * @retval EEXIST	the requested unit number is already allocated
1637  * @retval ENOMEM	memory allocation failure
1638  */
1639 static int
1640 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1641 {
1642 	const char *s;
1643 	int unit = *unitp;
1644 
1645 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1646 
1647 	/* Ask the parent bus if it wants to wire this device. */
1648 	if (unit == -1)
1649 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1650 		    &unit);
1651 
1652 	/* If we were given a wired unit number, check for existing device */
1653 	/* XXX imp XXX */
1654 	if (unit != -1) {
1655 		if (unit >= 0 && unit < dc->maxunit &&
1656 		    dc->devices[unit] != NULL) {
1657 			if (bootverbose)
1658 				printf("%s: %s%d already exists; skipping it\n",
1659 				    dc->name, dc->name, *unitp);
1660 			return (EEXIST);
1661 		}
1662 	} else {
1663 		/* Unwired device, find the next available slot for it */
1664 		unit = 0;
1665 		for (unit = 0;; unit++) {
1666 			/* If there is an "at" hint for a unit then skip it. */
1667 			if (resource_string_value(dc->name, unit, "at", &s) ==
1668 			    0)
1669 				continue;
1670 
1671 			/* If this device slot is already in use, skip it. */
1672 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1673 				continue;
1674 
1675 			break;
1676 		}
1677 	}
1678 
1679 	/*
1680 	 * We've selected a unit beyond the length of the table, so let's
1681 	 * extend the table to make room for all units up to and including
1682 	 * this one.
1683 	 */
1684 	if (unit >= dc->maxunit) {
1685 		device_t *newlist, *oldlist;
1686 		int newsize;
1687 
1688 		oldlist = dc->devices;
1689 		newsize = roundup((unit + 1),
1690 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1691 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1692 		if (!newlist)
1693 			return (ENOMEM);
1694 		if (oldlist != NULL)
1695 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1696 		bzero(newlist + dc->maxunit,
1697 		    sizeof(device_t) * (newsize - dc->maxunit));
1698 		dc->devices = newlist;
1699 		dc->maxunit = newsize;
1700 		if (oldlist != NULL)
1701 			free(oldlist, M_BUS);
1702 	}
1703 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1704 
1705 	*unitp = unit;
1706 	return (0);
1707 }
1708 
1709 /**
1710  * @internal
1711  * @brief Add a device to a devclass
1712  *
1713  * A unit number is allocated for the device (using the device's
1714  * preferred unit number if any) and the device is registered in the
1715  * devclass. This allows the device to be looked up by its unit
1716  * number, e.g. by decoding a dev_t minor number.
1717  *
1718  * @param dc		the devclass to add to
1719  * @param dev		the device to add
1720  *
1721  * @retval 0		success
1722  * @retval EEXIST	the requested unit number is already allocated
1723  * @retval ENOMEM	memory allocation failure
1724  */
1725 static int
1726 devclass_add_device(devclass_t dc, device_t dev)
1727 {
1728 	int buflen, error;
1729 
1730 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1731 
1732 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1733 	if (buflen < 0)
1734 		return (ENOMEM);
1735 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1736 	if (!dev->nameunit)
1737 		return (ENOMEM);
1738 
1739 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1740 		free(dev->nameunit, M_BUS);
1741 		dev->nameunit = NULL;
1742 		return (error);
1743 	}
1744 	dc->devices[dev->unit] = dev;
1745 	dev->devclass = dc;
1746 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1747 
1748 	return (0);
1749 }
1750 
1751 /**
1752  * @internal
1753  * @brief Delete a device from a devclass
1754  *
1755  * The device is removed from the devclass's device list and its unit
1756  * number is freed.
1757 
1758  * @param dc		the devclass to delete from
1759  * @param dev		the device to delete
1760  *
1761  * @retval 0		success
1762  */
1763 static int
1764 devclass_delete_device(devclass_t dc, device_t dev)
1765 {
1766 	if (!dc || !dev)
1767 		return (0);
1768 
1769 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1770 
1771 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1772 		panic("devclass_delete_device: inconsistent device class");
1773 	dc->devices[dev->unit] = NULL;
1774 	if (dev->flags & DF_WILDCARD)
1775 		dev->unit = -1;
1776 	dev->devclass = NULL;
1777 	free(dev->nameunit, M_BUS);
1778 	dev->nameunit = NULL;
1779 
1780 	return (0);
1781 }
1782 
1783 /**
1784  * @internal
1785  * @brief Make a new device and add it as a child of @p parent
1786  *
1787  * @param parent	the parent of the new device
1788  * @param name		the devclass name of the new device or @c NULL
1789  *			to leave the devclass unspecified
1790  * @parem unit		the unit number of the new device of @c -1 to
1791  *			leave the unit number unspecified
1792  *
1793  * @returns the new device
1794  */
1795 static device_t
1796 make_device(device_t parent, const char *name, int unit)
1797 {
1798 	device_t dev;
1799 	devclass_t dc;
1800 
1801 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1802 
1803 	if (name) {
1804 		dc = devclass_find_internal(name, NULL, TRUE);
1805 		if (!dc) {
1806 			printf("make_device: can't find device class %s\n",
1807 			    name);
1808 			return (NULL);
1809 		}
1810 	} else {
1811 		dc = NULL;
1812 	}
1813 
1814 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1815 	if (!dev)
1816 		return (NULL);
1817 
1818 	dev->parent = parent;
1819 	TAILQ_INIT(&dev->children);
1820 	kobj_init((kobj_t) dev, &null_class);
1821 	dev->driver = NULL;
1822 	dev->devclass = NULL;
1823 	dev->unit = unit;
1824 	dev->nameunit = NULL;
1825 	dev->desc = NULL;
1826 	dev->busy = 0;
1827 	dev->devflags = 0;
1828 	dev->flags = DF_ENABLED;
1829 	dev->order = 0;
1830 	if (unit == -1)
1831 		dev->flags |= DF_WILDCARD;
1832 	if (name) {
1833 		dev->flags |= DF_FIXEDCLASS;
1834 		if (devclass_add_device(dc, dev)) {
1835 			kobj_delete((kobj_t) dev, M_BUS);
1836 			return (NULL);
1837 		}
1838 	}
1839 	if (parent != NULL && device_has_quiet_children(parent))
1840 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1841 	dev->ivars = NULL;
1842 	dev->softc = NULL;
1843 
1844 	dev->state = DS_NOTPRESENT;
1845 
1846 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1847 	bus_data_generation_update();
1848 
1849 	return (dev);
1850 }
1851 
1852 /**
1853  * @internal
1854  * @brief Print a description of a device.
1855  */
1856 static int
1857 device_print_child(device_t dev, device_t child)
1858 {
1859 	int retval = 0;
1860 
1861 	if (device_is_alive(child))
1862 		retval += BUS_PRINT_CHILD(dev, child);
1863 	else
1864 		retval += device_printf(child, " not found\n");
1865 
1866 	return (retval);
1867 }
1868 
1869 /**
1870  * @brief Create a new device
1871  *
1872  * This creates a new device and adds it as a child of an existing
1873  * parent device. The new device will be added after the last existing
1874  * child with order zero.
1875  *
1876  * @param dev		the device which will be the parent of the
1877  *			new child device
1878  * @param name		devclass name for new device or @c NULL if not
1879  *			specified
1880  * @param unit		unit number for new device or @c -1 if not
1881  *			specified
1882  *
1883  * @returns		the new device
1884  */
1885 device_t
1886 device_add_child(device_t dev, const char *name, int unit)
1887 {
1888 	return (device_add_child_ordered(dev, 0, name, unit));
1889 }
1890 
1891 /**
1892  * @brief Create a new device
1893  *
1894  * This creates a new device and adds it as a child of an existing
1895  * parent device. The new device will be added after the last existing
1896  * child with the same order.
1897  *
1898  * @param dev		the device which will be the parent of the
1899  *			new child device
1900  * @param order		a value which is used to partially sort the
1901  *			children of @p dev - devices created using
1902  *			lower values of @p order appear first in @p
1903  *			dev's list of children
1904  * @param name		devclass name for new device or @c NULL if not
1905  *			specified
1906  * @param unit		unit number for new device or @c -1 if not
1907  *			specified
1908  *
1909  * @returns		the new device
1910  */
1911 device_t
1912 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1913 {
1914 	device_t child;
1915 	device_t place;
1916 
1917 	PDEBUG(("%s at %s with order %u as unit %d",
1918 	    name, DEVICENAME(dev), order, unit));
1919 	KASSERT(name != NULL || unit == -1,
1920 	    ("child device with wildcard name and specific unit number"));
1921 
1922 	child = make_device(dev, name, unit);
1923 	if (child == NULL)
1924 		return (child);
1925 	child->order = order;
1926 
1927 	TAILQ_FOREACH(place, &dev->children, link) {
1928 		if (place->order > order)
1929 			break;
1930 	}
1931 
1932 	if (place) {
1933 		/*
1934 		 * The device 'place' is the first device whose order is
1935 		 * greater than the new child.
1936 		 */
1937 		TAILQ_INSERT_BEFORE(place, child, link);
1938 	} else {
1939 		/*
1940 		 * The new child's order is greater or equal to the order of
1941 		 * any existing device. Add the child to the tail of the list.
1942 		 */
1943 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1944 	}
1945 
1946 	bus_data_generation_update();
1947 	return (child);
1948 }
1949 
1950 /**
1951  * @brief Delete a device
1952  *
1953  * This function deletes a device along with all of its children. If
1954  * the device currently has a driver attached to it, the device is
1955  * detached first using device_detach().
1956  *
1957  * @param dev		the parent device
1958  * @param child		the device to delete
1959  *
1960  * @retval 0		success
1961  * @retval non-zero	a unit error code describing the error
1962  */
1963 int
1964 device_delete_child(device_t dev, device_t child)
1965 {
1966 	int error;
1967 	device_t grandchild;
1968 
1969 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1970 
1971 	/* detach parent before deleting children, if any */
1972 	if ((error = device_detach(child)) != 0)
1973 		return (error);
1974 
1975 	/* remove children second */
1976 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1977 		error = device_delete_child(child, grandchild);
1978 		if (error)
1979 			return (error);
1980 	}
1981 
1982 	if (child->devclass)
1983 		devclass_delete_device(child->devclass, child);
1984 	if (child->parent)
1985 		BUS_CHILD_DELETED(dev, child);
1986 	TAILQ_REMOVE(&dev->children, child, link);
1987 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1988 	kobj_delete((kobj_t) child, M_BUS);
1989 
1990 	bus_data_generation_update();
1991 	return (0);
1992 }
1993 
1994 /**
1995  * @brief Delete all children devices of the given device, if any.
1996  *
1997  * This function deletes all children devices of the given device, if
1998  * any, using the device_delete_child() function for each device it
1999  * finds. If a child device cannot be deleted, this function will
2000  * return an error code.
2001  *
2002  * @param dev		the parent device
2003  *
2004  * @retval 0		success
2005  * @retval non-zero	a device would not detach
2006  */
2007 int
2008 device_delete_children(device_t dev)
2009 {
2010 	device_t child;
2011 	int error;
2012 
2013 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2014 
2015 	error = 0;
2016 
2017 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2018 		error = device_delete_child(dev, child);
2019 		if (error) {
2020 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2021 			break;
2022 		}
2023 	}
2024 	return (error);
2025 }
2026 
2027 /**
2028  * @brief Find a device given a unit number
2029  *
2030  * This is similar to devclass_get_devices() but only searches for
2031  * devices which have @p dev as a parent.
2032  *
2033  * @param dev		the parent device to search
2034  * @param unit		the unit number to search for.  If the unit is -1,
2035  *			return the first child of @p dev which has name
2036  *			@p classname (that is, the one with the lowest unit.)
2037  *
2038  * @returns		the device with the given unit number or @c
2039  *			NULL if there is no such device
2040  */
2041 device_t
2042 device_find_child(device_t dev, const char *classname, int unit)
2043 {
2044 	devclass_t dc;
2045 	device_t child;
2046 
2047 	dc = devclass_find(classname);
2048 	if (!dc)
2049 		return (NULL);
2050 
2051 	if (unit != -1) {
2052 		child = devclass_get_device(dc, unit);
2053 		if (child && child->parent == dev)
2054 			return (child);
2055 	} else {
2056 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2057 			child = devclass_get_device(dc, unit);
2058 			if (child && child->parent == dev)
2059 				return (child);
2060 		}
2061 	}
2062 	return (NULL);
2063 }
2064 
2065 /**
2066  * @internal
2067  */
2068 static driverlink_t
2069 first_matching_driver(devclass_t dc, device_t dev)
2070 {
2071 	if (dev->devclass)
2072 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2073 	return (TAILQ_FIRST(&dc->drivers));
2074 }
2075 
2076 /**
2077  * @internal
2078  */
2079 static driverlink_t
2080 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2081 {
2082 	if (dev->devclass) {
2083 		driverlink_t dl;
2084 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2085 			if (!strcmp(dev->devclass->name, dl->driver->name))
2086 				return (dl);
2087 		return (NULL);
2088 	}
2089 	return (TAILQ_NEXT(last, link));
2090 }
2091 
2092 /**
2093  * @internal
2094  */
2095 int
2096 device_probe_child(device_t dev, device_t child)
2097 {
2098 	devclass_t dc;
2099 	driverlink_t best = NULL;
2100 	driverlink_t dl;
2101 	int result, pri = 0;
2102 	int hasclass = (child->devclass != NULL);
2103 
2104 	GIANT_REQUIRED;
2105 
2106 	dc = dev->devclass;
2107 	if (!dc)
2108 		panic("device_probe_child: parent device has no devclass");
2109 
2110 	/*
2111 	 * If the state is already probed, then return.  However, don't
2112 	 * return if we can rebid this object.
2113 	 */
2114 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2115 		return (0);
2116 
2117 	for (; dc; dc = dc->parent) {
2118 		for (dl = first_matching_driver(dc, child);
2119 		     dl;
2120 		     dl = next_matching_driver(dc, child, dl)) {
2121 			/* If this driver's pass is too high, then ignore it. */
2122 			if (dl->pass > bus_current_pass)
2123 				continue;
2124 
2125 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2126 			result = device_set_driver(child, dl->driver);
2127 			if (result == ENOMEM)
2128 				return (result);
2129 			else if (result != 0)
2130 				continue;
2131 			if (!hasclass) {
2132 				if (device_set_devclass(child,
2133 				    dl->driver->name) != 0) {
2134 					char const * devname =
2135 					    device_get_name(child);
2136 					if (devname == NULL)
2137 						devname = "(unknown)";
2138 					printf("driver bug: Unable to set "
2139 					    "devclass (class: %s "
2140 					    "devname: %s)\n",
2141 					    dl->driver->name,
2142 					    devname);
2143 					(void)device_set_driver(child, NULL);
2144 					continue;
2145 				}
2146 			}
2147 
2148 			/* Fetch any flags for the device before probing. */
2149 			resource_int_value(dl->driver->name, child->unit,
2150 			    "flags", &child->devflags);
2151 
2152 			result = DEVICE_PROBE(child);
2153 
2154 			/* Reset flags and devclass before the next probe. */
2155 			child->devflags = 0;
2156 			if (!hasclass)
2157 				(void)device_set_devclass(child, NULL);
2158 
2159 			/*
2160 			 * If the driver returns SUCCESS, there can be
2161 			 * no higher match for this device.
2162 			 */
2163 			if (result == 0) {
2164 				best = dl;
2165 				pri = 0;
2166 				break;
2167 			}
2168 
2169 			/*
2170 			 * Reset DF_QUIET in case this driver doesn't
2171 			 * end up as the best driver.
2172 			 */
2173 			device_verbose(child);
2174 
2175 			/*
2176 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2177 			 * only match on devices whose driver was explicitly
2178 			 * specified.
2179 			 */
2180 			if (result <= BUS_PROBE_NOWILDCARD &&
2181 			    !(child->flags & DF_FIXEDCLASS)) {
2182 				result = ENXIO;
2183 			}
2184 
2185 			/*
2186 			 * The driver returned an error so it
2187 			 * certainly doesn't match.
2188 			 */
2189 			if (result > 0) {
2190 				(void)device_set_driver(child, NULL);
2191 				continue;
2192 			}
2193 
2194 			/*
2195 			 * A priority lower than SUCCESS, remember the
2196 			 * best matching driver. Initialise the value
2197 			 * of pri for the first match.
2198 			 */
2199 			if (best == NULL || result > pri) {
2200 				best = dl;
2201 				pri = result;
2202 				continue;
2203 			}
2204 		}
2205 		/*
2206 		 * If we have an unambiguous match in this devclass,
2207 		 * don't look in the parent.
2208 		 */
2209 		if (best && pri == 0)
2210 			break;
2211 	}
2212 
2213 	/*
2214 	 * If we found a driver, change state and initialise the devclass.
2215 	 */
2216 	/* XXX What happens if we rebid and got no best? */
2217 	if (best) {
2218 		/*
2219 		 * If this device was attached, and we were asked to
2220 		 * rescan, and it is a different driver, then we have
2221 		 * to detach the old driver and reattach this new one.
2222 		 * Note, we don't have to check for DF_REBID here
2223 		 * because if the state is > DS_ALIVE, we know it must
2224 		 * be.
2225 		 *
2226 		 * This assumes that all DF_REBID drivers can have
2227 		 * their probe routine called at any time and that
2228 		 * they are idempotent as well as completely benign in
2229 		 * normal operations.
2230 		 *
2231 		 * We also have to make sure that the detach
2232 		 * succeeded, otherwise we fail the operation (or
2233 		 * maybe it should just fail silently?  I'm torn).
2234 		 */
2235 		if (child->state > DS_ALIVE && best->driver != child->driver)
2236 			if ((result = device_detach(dev)) != 0)
2237 				return (result);
2238 
2239 		/* Set the winning driver, devclass, and flags. */
2240 		if (!child->devclass) {
2241 			result = device_set_devclass(child, best->driver->name);
2242 			if (result != 0)
2243 				return (result);
2244 		}
2245 		result = device_set_driver(child, best->driver);
2246 		if (result != 0)
2247 			return (result);
2248 		resource_int_value(best->driver->name, child->unit,
2249 		    "flags", &child->devflags);
2250 
2251 		if (pri < 0) {
2252 			/*
2253 			 * A bit bogus. Call the probe method again to make
2254 			 * sure that we have the right description.
2255 			 */
2256 			DEVICE_PROBE(child);
2257 #if 0
2258 			child->flags |= DF_REBID;
2259 #endif
2260 		} else
2261 			child->flags &= ~DF_REBID;
2262 		child->state = DS_ALIVE;
2263 
2264 		bus_data_generation_update();
2265 		return (0);
2266 	}
2267 
2268 	return (ENXIO);
2269 }
2270 
2271 /**
2272  * @brief Return the parent of a device
2273  */
2274 device_t
2275 device_get_parent(device_t dev)
2276 {
2277 	return (dev->parent);
2278 }
2279 
2280 /**
2281  * @brief Get a list of children of a device
2282  *
2283  * An array containing a list of all the children of the given device
2284  * is allocated and returned in @p *devlistp. The number of devices
2285  * in the array is returned in @p *devcountp. The caller should free
2286  * the array using @c free(p, M_TEMP).
2287  *
2288  * @param dev		the device to examine
2289  * @param devlistp	points at location for array pointer return
2290  *			value
2291  * @param devcountp	points at location for array size return value
2292  *
2293  * @retval 0		success
2294  * @retval ENOMEM	the array allocation failed
2295  */
2296 int
2297 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2298 {
2299 	int count;
2300 	device_t child;
2301 	device_t *list;
2302 
2303 	count = 0;
2304 	TAILQ_FOREACH(child, &dev->children, link) {
2305 		count++;
2306 	}
2307 	if (count == 0) {
2308 		*devlistp = NULL;
2309 		*devcountp = 0;
2310 		return (0);
2311 	}
2312 
2313 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2314 	if (!list)
2315 		return (ENOMEM);
2316 
2317 	count = 0;
2318 	TAILQ_FOREACH(child, &dev->children, link) {
2319 		list[count] = child;
2320 		count++;
2321 	}
2322 
2323 	*devlistp = list;
2324 	*devcountp = count;
2325 
2326 	return (0);
2327 }
2328 
2329 /**
2330  * @brief Return the current driver for the device or @c NULL if there
2331  * is no driver currently attached
2332  */
2333 driver_t *
2334 device_get_driver(device_t dev)
2335 {
2336 	return (dev->driver);
2337 }
2338 
2339 /**
2340  * @brief Return the current devclass for the device or @c NULL if
2341  * there is none.
2342  */
2343 devclass_t
2344 device_get_devclass(device_t dev)
2345 {
2346 	return (dev->devclass);
2347 }
2348 
2349 /**
2350  * @brief Return the name of the device's devclass or @c NULL if there
2351  * is none.
2352  */
2353 const char *
2354 device_get_name(device_t dev)
2355 {
2356 	if (dev != NULL && dev->devclass)
2357 		return (devclass_get_name(dev->devclass));
2358 	return (NULL);
2359 }
2360 
2361 /**
2362  * @brief Return a string containing the device's devclass name
2363  * followed by an ascii representation of the device's unit number
2364  * (e.g. @c "foo2").
2365  */
2366 const char *
2367 device_get_nameunit(device_t dev)
2368 {
2369 	return (dev->nameunit);
2370 }
2371 
2372 /**
2373  * @brief Return the device's unit number.
2374  */
2375 int
2376 device_get_unit(device_t dev)
2377 {
2378 	return (dev->unit);
2379 }
2380 
2381 /**
2382  * @brief Return the device's description string
2383  */
2384 const char *
2385 device_get_desc(device_t dev)
2386 {
2387 	return (dev->desc);
2388 }
2389 
2390 /**
2391  * @brief Return the device's flags
2392  */
2393 uint32_t
2394 device_get_flags(device_t dev)
2395 {
2396 	return (dev->devflags);
2397 }
2398 
2399 struct sysctl_ctx_list *
2400 device_get_sysctl_ctx(device_t dev)
2401 {
2402 	return (&dev->sysctl_ctx);
2403 }
2404 
2405 struct sysctl_oid *
2406 device_get_sysctl_tree(device_t dev)
2407 {
2408 	return (dev->sysctl_tree);
2409 }
2410 
2411 /**
2412  * @brief Print the name of the device followed by a colon and a space
2413  *
2414  * @returns the number of characters printed
2415  */
2416 int
2417 device_print_prettyname(device_t dev)
2418 {
2419 	const char *name = device_get_name(dev);
2420 
2421 	if (name == NULL)
2422 		return (printf("unknown: "));
2423 	return (printf("%s%d: ", name, device_get_unit(dev)));
2424 }
2425 
2426 /**
2427  * @brief Print the name of the device followed by a colon, a space
2428  * and the result of calling vprintf() with the value of @p fmt and
2429  * the following arguments.
2430  *
2431  * @returns the number of characters printed
2432  */
2433 int
2434 device_printf(device_t dev, const char * fmt, ...)
2435 {
2436 	char buf[128];
2437 	struct sbuf sb;
2438 	const char *name;
2439 	va_list ap;
2440 	size_t retval;
2441 
2442 	retval = 0;
2443 
2444 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2445 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2446 
2447 	name = device_get_name(dev);
2448 
2449 	if (name == NULL)
2450 		sbuf_cat(&sb, "unknown: ");
2451 	else
2452 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2453 
2454 	va_start(ap, fmt);
2455 	sbuf_vprintf(&sb, fmt, ap);
2456 	va_end(ap);
2457 
2458 	sbuf_finish(&sb);
2459 	sbuf_delete(&sb);
2460 
2461 	return (retval);
2462 }
2463 
2464 /**
2465  * @internal
2466  */
2467 static void
2468 device_set_desc_internal(device_t dev, const char* desc, int copy)
2469 {
2470 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2471 		free(dev->desc, M_BUS);
2472 		dev->flags &= ~DF_DESCMALLOCED;
2473 		dev->desc = NULL;
2474 	}
2475 
2476 	if (copy && desc) {
2477 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2478 		if (dev->desc) {
2479 			strcpy(dev->desc, desc);
2480 			dev->flags |= DF_DESCMALLOCED;
2481 		}
2482 	} else {
2483 		/* Avoid a -Wcast-qual warning */
2484 		dev->desc = (char *)(uintptr_t) desc;
2485 	}
2486 
2487 	bus_data_generation_update();
2488 }
2489 
2490 /**
2491  * @brief Set the device's description
2492  *
2493  * The value of @c desc should be a string constant that will not
2494  * change (at least until the description is changed in a subsequent
2495  * call to device_set_desc() or device_set_desc_copy()).
2496  */
2497 void
2498 device_set_desc(device_t dev, const char* desc)
2499 {
2500 	device_set_desc_internal(dev, desc, FALSE);
2501 }
2502 
2503 /**
2504  * @brief Set the device's description
2505  *
2506  * The string pointed to by @c desc is copied. Use this function if
2507  * the device description is generated, (e.g. with sprintf()).
2508  */
2509 void
2510 device_set_desc_copy(device_t dev, const char* desc)
2511 {
2512 	device_set_desc_internal(dev, desc, TRUE);
2513 }
2514 
2515 /**
2516  * @brief Set the device's flags
2517  */
2518 void
2519 device_set_flags(device_t dev, uint32_t flags)
2520 {
2521 	dev->devflags = flags;
2522 }
2523 
2524 /**
2525  * @brief Return the device's softc field
2526  *
2527  * The softc is allocated and zeroed when a driver is attached, based
2528  * on the size field of the driver.
2529  */
2530 void *
2531 device_get_softc(device_t dev)
2532 {
2533 	return (dev->softc);
2534 }
2535 
2536 /**
2537  * @brief Set the device's softc field
2538  *
2539  * Most drivers do not need to use this since the softc is allocated
2540  * automatically when the driver is attached.
2541  */
2542 void
2543 device_set_softc(device_t dev, void *softc)
2544 {
2545 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2546 		free_domain(dev->softc, M_BUS_SC);
2547 	dev->softc = softc;
2548 	if (dev->softc)
2549 		dev->flags |= DF_EXTERNALSOFTC;
2550 	else
2551 		dev->flags &= ~DF_EXTERNALSOFTC;
2552 }
2553 
2554 /**
2555  * @brief Free claimed softc
2556  *
2557  * Most drivers do not need to use this since the softc is freed
2558  * automatically when the driver is detached.
2559  */
2560 void
2561 device_free_softc(void *softc)
2562 {
2563 	free_domain(softc, M_BUS_SC);
2564 }
2565 
2566 /**
2567  * @brief Claim softc
2568  *
2569  * This function can be used to let the driver free the automatically
2570  * allocated softc using "device_free_softc()". This function is
2571  * useful when the driver is refcounting the softc and the softc
2572  * cannot be freed when the "device_detach" method is called.
2573  */
2574 void
2575 device_claim_softc(device_t dev)
2576 {
2577 	if (dev->softc)
2578 		dev->flags |= DF_EXTERNALSOFTC;
2579 	else
2580 		dev->flags &= ~DF_EXTERNALSOFTC;
2581 }
2582 
2583 /**
2584  * @brief Get the device's ivars field
2585  *
2586  * The ivars field is used by the parent device to store per-device
2587  * state (e.g. the physical location of the device or a list of
2588  * resources).
2589  */
2590 void *
2591 device_get_ivars(device_t dev)
2592 {
2593 
2594 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2595 	return (dev->ivars);
2596 }
2597 
2598 /**
2599  * @brief Set the device's ivars field
2600  */
2601 void
2602 device_set_ivars(device_t dev, void * ivars)
2603 {
2604 
2605 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2606 	dev->ivars = ivars;
2607 }
2608 
2609 /**
2610  * @brief Return the device's state
2611  */
2612 device_state_t
2613 device_get_state(device_t dev)
2614 {
2615 	return (dev->state);
2616 }
2617 
2618 /**
2619  * @brief Set the DF_ENABLED flag for the device
2620  */
2621 void
2622 device_enable(device_t dev)
2623 {
2624 	dev->flags |= DF_ENABLED;
2625 }
2626 
2627 /**
2628  * @brief Clear the DF_ENABLED flag for the device
2629  */
2630 void
2631 device_disable(device_t dev)
2632 {
2633 	dev->flags &= ~DF_ENABLED;
2634 }
2635 
2636 /**
2637  * @brief Increment the busy counter for the device
2638  */
2639 void
2640 device_busy(device_t dev)
2641 {
2642 	if (dev->state < DS_ATTACHING)
2643 		panic("device_busy: called for unattached device");
2644 	if (dev->busy == 0 && dev->parent)
2645 		device_busy(dev->parent);
2646 	dev->busy++;
2647 	if (dev->state == DS_ATTACHED)
2648 		dev->state = DS_BUSY;
2649 }
2650 
2651 /**
2652  * @brief Decrement the busy counter for the device
2653  */
2654 void
2655 device_unbusy(device_t dev)
2656 {
2657 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2658 	    dev->state != DS_ATTACHING)
2659 		panic("device_unbusy: called for non-busy device %s",
2660 		    device_get_nameunit(dev));
2661 	dev->busy--;
2662 	if (dev->busy == 0) {
2663 		if (dev->parent)
2664 			device_unbusy(dev->parent);
2665 		if (dev->state == DS_BUSY)
2666 			dev->state = DS_ATTACHED;
2667 	}
2668 }
2669 
2670 /**
2671  * @brief Set the DF_QUIET flag for the device
2672  */
2673 void
2674 device_quiet(device_t dev)
2675 {
2676 	dev->flags |= DF_QUIET;
2677 }
2678 
2679 /**
2680  * @brief Set the DF_QUIET_CHILDREN flag for the device
2681  */
2682 void
2683 device_quiet_children(device_t dev)
2684 {
2685 	dev->flags |= DF_QUIET_CHILDREN;
2686 }
2687 
2688 /**
2689  * @brief Clear the DF_QUIET flag for the device
2690  */
2691 void
2692 device_verbose(device_t dev)
2693 {
2694 	dev->flags &= ~DF_QUIET;
2695 }
2696 
2697 /**
2698  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2699  */
2700 int
2701 device_has_quiet_children(device_t dev)
2702 {
2703 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2704 }
2705 
2706 /**
2707  * @brief Return non-zero if the DF_QUIET flag is set on the device
2708  */
2709 int
2710 device_is_quiet(device_t dev)
2711 {
2712 	return ((dev->flags & DF_QUIET) != 0);
2713 }
2714 
2715 /**
2716  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2717  */
2718 int
2719 device_is_enabled(device_t dev)
2720 {
2721 	return ((dev->flags & DF_ENABLED) != 0);
2722 }
2723 
2724 /**
2725  * @brief Return non-zero if the device was successfully probed
2726  */
2727 int
2728 device_is_alive(device_t dev)
2729 {
2730 	return (dev->state >= DS_ALIVE);
2731 }
2732 
2733 /**
2734  * @brief Return non-zero if the device currently has a driver
2735  * attached to it
2736  */
2737 int
2738 device_is_attached(device_t dev)
2739 {
2740 	return (dev->state >= DS_ATTACHED);
2741 }
2742 
2743 /**
2744  * @brief Return non-zero if the device is currently suspended.
2745  */
2746 int
2747 device_is_suspended(device_t dev)
2748 {
2749 	return ((dev->flags & DF_SUSPENDED) != 0);
2750 }
2751 
2752 /**
2753  * @brief Set the devclass of a device
2754  * @see devclass_add_device().
2755  */
2756 int
2757 device_set_devclass(device_t dev, const char *classname)
2758 {
2759 	devclass_t dc;
2760 	int error;
2761 
2762 	if (!classname) {
2763 		if (dev->devclass)
2764 			devclass_delete_device(dev->devclass, dev);
2765 		return (0);
2766 	}
2767 
2768 	if (dev->devclass) {
2769 		printf("device_set_devclass: device class already set\n");
2770 		return (EINVAL);
2771 	}
2772 
2773 	dc = devclass_find_internal(classname, NULL, TRUE);
2774 	if (!dc)
2775 		return (ENOMEM);
2776 
2777 	error = devclass_add_device(dc, dev);
2778 
2779 	bus_data_generation_update();
2780 	return (error);
2781 }
2782 
2783 /**
2784  * @brief Set the devclass of a device and mark the devclass fixed.
2785  * @see device_set_devclass()
2786  */
2787 int
2788 device_set_devclass_fixed(device_t dev, const char *classname)
2789 {
2790 	int error;
2791 
2792 	if (classname == NULL)
2793 		return (EINVAL);
2794 
2795 	error = device_set_devclass(dev, classname);
2796 	if (error)
2797 		return (error);
2798 	dev->flags |= DF_FIXEDCLASS;
2799 	return (0);
2800 }
2801 
2802 /**
2803  * @brief Query the device to determine if it's of a fixed devclass
2804  * @see device_set_devclass_fixed()
2805  */
2806 bool
2807 device_is_devclass_fixed(device_t dev)
2808 {
2809 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2810 }
2811 
2812 /**
2813  * @brief Set the driver of a device
2814  *
2815  * @retval 0		success
2816  * @retval EBUSY	the device already has a driver attached
2817  * @retval ENOMEM	a memory allocation failure occurred
2818  */
2819 int
2820 device_set_driver(device_t dev, driver_t *driver)
2821 {
2822 	int domain;
2823 	struct domainset *policy;
2824 
2825 	if (dev->state >= DS_ATTACHED)
2826 		return (EBUSY);
2827 
2828 	if (dev->driver == driver)
2829 		return (0);
2830 
2831 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2832 		free_domain(dev->softc, M_BUS_SC);
2833 		dev->softc = NULL;
2834 	}
2835 	device_set_desc(dev, NULL);
2836 	kobj_delete((kobj_t) dev, NULL);
2837 	dev->driver = driver;
2838 	if (driver) {
2839 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2840 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2841 			if (bus_get_domain(dev, &domain) == 0)
2842 				policy = DOMAINSET_PREF(domain);
2843 			else
2844 				policy = DOMAINSET_RR();
2845 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2846 			    policy, M_NOWAIT | M_ZERO);
2847 			if (!dev->softc) {
2848 				kobj_delete((kobj_t) dev, NULL);
2849 				kobj_init((kobj_t) dev, &null_class);
2850 				dev->driver = NULL;
2851 				return (ENOMEM);
2852 			}
2853 		}
2854 	} else {
2855 		kobj_init((kobj_t) dev, &null_class);
2856 	}
2857 
2858 	bus_data_generation_update();
2859 	return (0);
2860 }
2861 
2862 /**
2863  * @brief Probe a device, and return this status.
2864  *
2865  * This function is the core of the device autoconfiguration
2866  * system. Its purpose is to select a suitable driver for a device and
2867  * then call that driver to initialise the hardware appropriately. The
2868  * driver is selected by calling the DEVICE_PROBE() method of a set of
2869  * candidate drivers and then choosing the driver which returned the
2870  * best value. This driver is then attached to the device using
2871  * device_attach().
2872  *
2873  * The set of suitable drivers is taken from the list of drivers in
2874  * the parent device's devclass. If the device was originally created
2875  * with a specific class name (see device_add_child()), only drivers
2876  * with that name are probed, otherwise all drivers in the devclass
2877  * are probed. If no drivers return successful probe values in the
2878  * parent devclass, the search continues in the parent of that
2879  * devclass (see devclass_get_parent()) if any.
2880  *
2881  * @param dev		the device to initialise
2882  *
2883  * @retval 0		success
2884  * @retval ENXIO	no driver was found
2885  * @retval ENOMEM	memory allocation failure
2886  * @retval non-zero	some other unix error code
2887  * @retval -1		Device already attached
2888  */
2889 int
2890 device_probe(device_t dev)
2891 {
2892 	int error;
2893 
2894 	GIANT_REQUIRED;
2895 
2896 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2897 		return (-1);
2898 
2899 	if (!(dev->flags & DF_ENABLED)) {
2900 		if (bootverbose && device_get_name(dev) != NULL) {
2901 			device_print_prettyname(dev);
2902 			printf("not probed (disabled)\n");
2903 		}
2904 		return (-1);
2905 	}
2906 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2907 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2908 		    !(dev->flags & DF_DONENOMATCH)) {
2909 			BUS_PROBE_NOMATCH(dev->parent, dev);
2910 			devnomatch(dev);
2911 			dev->flags |= DF_DONENOMATCH;
2912 		}
2913 		return (error);
2914 	}
2915 	return (0);
2916 }
2917 
2918 /**
2919  * @brief Probe a device and attach a driver if possible
2920  *
2921  * calls device_probe() and attaches if that was successful.
2922  */
2923 int
2924 device_probe_and_attach(device_t dev)
2925 {
2926 	int error;
2927 
2928 	GIANT_REQUIRED;
2929 
2930 	error = device_probe(dev);
2931 	if (error == -1)
2932 		return (0);
2933 	else if (error != 0)
2934 		return (error);
2935 
2936 	CURVNET_SET_QUIET(vnet0);
2937 	error = device_attach(dev);
2938 	CURVNET_RESTORE();
2939 	return error;
2940 }
2941 
2942 /**
2943  * @brief Attach a device driver to a device
2944  *
2945  * This function is a wrapper around the DEVICE_ATTACH() driver
2946  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2947  * device's sysctl tree, optionally prints a description of the device
2948  * and queues a notification event for user-based device management
2949  * services.
2950  *
2951  * Normally this function is only called internally from
2952  * device_probe_and_attach().
2953  *
2954  * @param dev		the device to initialise
2955  *
2956  * @retval 0		success
2957  * @retval ENXIO	no driver was found
2958  * @retval ENOMEM	memory allocation failure
2959  * @retval non-zero	some other unix error code
2960  */
2961 int
2962 device_attach(device_t dev)
2963 {
2964 	uint64_t attachtime;
2965 	uint16_t attachentropy;
2966 	int error;
2967 
2968 	if (resource_disabled(dev->driver->name, dev->unit)) {
2969 		device_disable(dev);
2970 		if (bootverbose)
2971 			 device_printf(dev, "disabled via hints entry\n");
2972 		return (ENXIO);
2973 	}
2974 
2975 	device_sysctl_init(dev);
2976 	if (!device_is_quiet(dev))
2977 		device_print_child(dev->parent, dev);
2978 	attachtime = get_cyclecount();
2979 	dev->state = DS_ATTACHING;
2980 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2981 		printf("device_attach: %s%d attach returned %d\n",
2982 		    dev->driver->name, dev->unit, error);
2983 		if (!(dev->flags & DF_FIXEDCLASS))
2984 			devclass_delete_device(dev->devclass, dev);
2985 		(void)device_set_driver(dev, NULL);
2986 		device_sysctl_fini(dev);
2987 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2988 		dev->state = DS_NOTPRESENT;
2989 		return (error);
2990 	}
2991 	dev->flags |= DF_ATTACHED_ONCE;
2992 	/* We only need the low bits of this time, but ranges from tens to thousands
2993 	 * have been seen, so keep 2 bytes' worth.
2994 	 */
2995 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
2996 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
2997 	device_sysctl_update(dev);
2998 	if (dev->busy)
2999 		dev->state = DS_BUSY;
3000 	else
3001 		dev->state = DS_ATTACHED;
3002 	dev->flags &= ~DF_DONENOMATCH;
3003 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3004 	devadded(dev);
3005 	return (0);
3006 }
3007 
3008 /**
3009  * @brief Detach a driver from a device
3010  *
3011  * This function is a wrapper around the DEVICE_DETACH() driver
3012  * method. If the call to DEVICE_DETACH() succeeds, it calls
3013  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3014  * notification event for user-based device management services and
3015  * cleans up the device's sysctl tree.
3016  *
3017  * @param dev		the device to un-initialise
3018  *
3019  * @retval 0		success
3020  * @retval ENXIO	no driver was found
3021  * @retval ENOMEM	memory allocation failure
3022  * @retval non-zero	some other unix error code
3023  */
3024 int
3025 device_detach(device_t dev)
3026 {
3027 	int error;
3028 
3029 	GIANT_REQUIRED;
3030 
3031 	PDEBUG(("%s", DEVICENAME(dev)));
3032 	if (dev->state == DS_BUSY)
3033 		return (EBUSY);
3034 	if (dev->state == DS_ATTACHING) {
3035 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3036 		return (EBUSY);
3037 	}
3038 	if (dev->state != DS_ATTACHED)
3039 		return (0);
3040 
3041 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3042 	if ((error = DEVICE_DETACH(dev)) != 0) {
3043 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3044 		    EVHDEV_DETACH_FAILED);
3045 		return (error);
3046 	} else {
3047 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3048 		    EVHDEV_DETACH_COMPLETE);
3049 	}
3050 	devremoved(dev);
3051 	if (!device_is_quiet(dev))
3052 		device_printf(dev, "detached\n");
3053 	if (dev->parent)
3054 		BUS_CHILD_DETACHED(dev->parent, dev);
3055 
3056 	if (!(dev->flags & DF_FIXEDCLASS))
3057 		devclass_delete_device(dev->devclass, dev);
3058 
3059 	device_verbose(dev);
3060 	dev->state = DS_NOTPRESENT;
3061 	(void)device_set_driver(dev, NULL);
3062 	device_sysctl_fini(dev);
3063 
3064 	return (0);
3065 }
3066 
3067 /**
3068  * @brief Tells a driver to quiesce itself.
3069  *
3070  * This function is a wrapper around the DEVICE_QUIESCE() driver
3071  * method. If the call to DEVICE_QUIESCE() succeeds.
3072  *
3073  * @param dev		the device to quiesce
3074  *
3075  * @retval 0		success
3076  * @retval ENXIO	no driver was found
3077  * @retval ENOMEM	memory allocation failure
3078  * @retval non-zero	some other unix error code
3079  */
3080 int
3081 device_quiesce(device_t dev)
3082 {
3083 
3084 	PDEBUG(("%s", DEVICENAME(dev)));
3085 	if (dev->state == DS_BUSY)
3086 		return (EBUSY);
3087 	if (dev->state != DS_ATTACHED)
3088 		return (0);
3089 
3090 	return (DEVICE_QUIESCE(dev));
3091 }
3092 
3093 /**
3094  * @brief Notify a device of system shutdown
3095  *
3096  * This function calls the DEVICE_SHUTDOWN() driver method if the
3097  * device currently has an attached driver.
3098  *
3099  * @returns the value returned by DEVICE_SHUTDOWN()
3100  */
3101 int
3102 device_shutdown(device_t dev)
3103 {
3104 	if (dev->state < DS_ATTACHED)
3105 		return (0);
3106 	return (DEVICE_SHUTDOWN(dev));
3107 }
3108 
3109 /**
3110  * @brief Set the unit number of a device
3111  *
3112  * This function can be used to override the unit number used for a
3113  * device (e.g. to wire a device to a pre-configured unit number).
3114  */
3115 int
3116 device_set_unit(device_t dev, int unit)
3117 {
3118 	devclass_t dc;
3119 	int err;
3120 
3121 	dc = device_get_devclass(dev);
3122 	if (unit < dc->maxunit && dc->devices[unit])
3123 		return (EBUSY);
3124 	err = devclass_delete_device(dc, dev);
3125 	if (err)
3126 		return (err);
3127 	dev->unit = unit;
3128 	err = devclass_add_device(dc, dev);
3129 	if (err)
3130 		return (err);
3131 
3132 	bus_data_generation_update();
3133 	return (0);
3134 }
3135 
3136 /*======================================*/
3137 /*
3138  * Some useful method implementations to make life easier for bus drivers.
3139  */
3140 
3141 void
3142 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3143 {
3144 
3145 	bzero(args, sz);
3146 	args->size = sz;
3147 	args->memattr = VM_MEMATTR_UNCACHEABLE;
3148 }
3149 
3150 /**
3151  * @brief Initialise a resource list.
3152  *
3153  * @param rl		the resource list to initialise
3154  */
3155 void
3156 resource_list_init(struct resource_list *rl)
3157 {
3158 	STAILQ_INIT(rl);
3159 }
3160 
3161 /**
3162  * @brief Reclaim memory used by a resource list.
3163  *
3164  * This function frees the memory for all resource entries on the list
3165  * (if any).
3166  *
3167  * @param rl		the resource list to free
3168  */
3169 void
3170 resource_list_free(struct resource_list *rl)
3171 {
3172 	struct resource_list_entry *rle;
3173 
3174 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3175 		if (rle->res)
3176 			panic("resource_list_free: resource entry is busy");
3177 		STAILQ_REMOVE_HEAD(rl, link);
3178 		free(rle, M_BUS);
3179 	}
3180 }
3181 
3182 /**
3183  * @brief Add a resource entry.
3184  *
3185  * This function adds a resource entry using the given @p type, @p
3186  * start, @p end and @p count values. A rid value is chosen by
3187  * searching sequentially for the first unused rid starting at zero.
3188  *
3189  * @param rl		the resource list to edit
3190  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3191  * @param start		the start address of the resource
3192  * @param end		the end address of the resource
3193  * @param count		XXX end-start+1
3194  */
3195 int
3196 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3197     rman_res_t end, rman_res_t count)
3198 {
3199 	int rid;
3200 
3201 	rid = 0;
3202 	while (resource_list_find(rl, type, rid) != NULL)
3203 		rid++;
3204 	resource_list_add(rl, type, rid, start, end, count);
3205 	return (rid);
3206 }
3207 
3208 /**
3209  * @brief Add or modify a resource entry.
3210  *
3211  * If an existing entry exists with the same type and rid, it will be
3212  * modified using the given values of @p start, @p end and @p
3213  * count. If no entry exists, a new one will be created using the
3214  * given values.  The resource list entry that matches is then returned.
3215  *
3216  * @param rl		the resource list to edit
3217  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3218  * @param rid		the resource identifier
3219  * @param start		the start address of the resource
3220  * @param end		the end address of the resource
3221  * @param count		XXX end-start+1
3222  */
3223 struct resource_list_entry *
3224 resource_list_add(struct resource_list *rl, int type, int rid,
3225     rman_res_t start, rman_res_t end, rman_res_t count)
3226 {
3227 	struct resource_list_entry *rle;
3228 
3229 	rle = resource_list_find(rl, type, rid);
3230 	if (!rle) {
3231 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3232 		    M_NOWAIT);
3233 		if (!rle)
3234 			panic("resource_list_add: can't record entry");
3235 		STAILQ_INSERT_TAIL(rl, rle, link);
3236 		rle->type = type;
3237 		rle->rid = rid;
3238 		rle->res = NULL;
3239 		rle->flags = 0;
3240 	}
3241 
3242 	if (rle->res)
3243 		panic("resource_list_add: resource entry is busy");
3244 
3245 	rle->start = start;
3246 	rle->end = end;
3247 	rle->count = count;
3248 	return (rle);
3249 }
3250 
3251 /**
3252  * @brief Determine if a resource entry is busy.
3253  *
3254  * Returns true if a resource entry is busy meaning that it has an
3255  * associated resource that is not an unallocated "reserved" resource.
3256  *
3257  * @param rl		the resource list to search
3258  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3259  * @param rid		the resource identifier
3260  *
3261  * @returns Non-zero if the entry is busy, zero otherwise.
3262  */
3263 int
3264 resource_list_busy(struct resource_list *rl, int type, int rid)
3265 {
3266 	struct resource_list_entry *rle;
3267 
3268 	rle = resource_list_find(rl, type, rid);
3269 	if (rle == NULL || rle->res == NULL)
3270 		return (0);
3271 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3272 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3273 		    ("reserved resource is active"));
3274 		return (0);
3275 	}
3276 	return (1);
3277 }
3278 
3279 /**
3280  * @brief Determine if a resource entry is reserved.
3281  *
3282  * Returns true if a resource entry is reserved meaning that it has an
3283  * associated "reserved" resource.  The resource can either be
3284  * allocated or unallocated.
3285  *
3286  * @param rl		the resource list to search
3287  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3288  * @param rid		the resource identifier
3289  *
3290  * @returns Non-zero if the entry is reserved, zero otherwise.
3291  */
3292 int
3293 resource_list_reserved(struct resource_list *rl, int type, int rid)
3294 {
3295 	struct resource_list_entry *rle;
3296 
3297 	rle = resource_list_find(rl, type, rid);
3298 	if (rle != NULL && rle->flags & RLE_RESERVED)
3299 		return (1);
3300 	return (0);
3301 }
3302 
3303 /**
3304  * @brief Find a resource entry by type and rid.
3305  *
3306  * @param rl		the resource list to search
3307  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3308  * @param rid		the resource identifier
3309  *
3310  * @returns the resource entry pointer or NULL if there is no such
3311  * entry.
3312  */
3313 struct resource_list_entry *
3314 resource_list_find(struct resource_list *rl, int type, int rid)
3315 {
3316 	struct resource_list_entry *rle;
3317 
3318 	STAILQ_FOREACH(rle, rl, link) {
3319 		if (rle->type == type && rle->rid == rid)
3320 			return (rle);
3321 	}
3322 	return (NULL);
3323 }
3324 
3325 /**
3326  * @brief Delete a resource entry.
3327  *
3328  * @param rl		the resource list to edit
3329  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3330  * @param rid		the resource identifier
3331  */
3332 void
3333 resource_list_delete(struct resource_list *rl, int type, int rid)
3334 {
3335 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3336 
3337 	if (rle) {
3338 		if (rle->res != NULL)
3339 			panic("resource_list_delete: resource has not been released");
3340 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3341 		free(rle, M_BUS);
3342 	}
3343 }
3344 
3345 /**
3346  * @brief Allocate a reserved resource
3347  *
3348  * This can be used by buses to force the allocation of resources
3349  * that are always active in the system even if they are not allocated
3350  * by a driver (e.g. PCI BARs).  This function is usually called when
3351  * adding a new child to the bus.  The resource is allocated from the
3352  * parent bus when it is reserved.  The resource list entry is marked
3353  * with RLE_RESERVED to note that it is a reserved resource.
3354  *
3355  * Subsequent attempts to allocate the resource with
3356  * resource_list_alloc() will succeed the first time and will set
3357  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3358  * resource that has been allocated is released with
3359  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3360  * the actual resource remains allocated.  The resource can be released to
3361  * the parent bus by calling resource_list_unreserve().
3362  *
3363  * @param rl		the resource list to allocate from
3364  * @param bus		the parent device of @p child
3365  * @param child		the device for which the resource is being reserved
3366  * @param type		the type of resource to allocate
3367  * @param rid		a pointer to the resource identifier
3368  * @param start		hint at the start of the resource range - pass
3369  *			@c 0 for any start address
3370  * @param end		hint at the end of the resource range - pass
3371  *			@c ~0 for any end address
3372  * @param count		hint at the size of range required - pass @c 1
3373  *			for any size
3374  * @param flags		any extra flags to control the resource
3375  *			allocation - see @c RF_XXX flags in
3376  *			<sys/rman.h> for details
3377  *
3378  * @returns		the resource which was allocated or @c NULL if no
3379  *			resource could be allocated
3380  */
3381 struct resource *
3382 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3383     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3384 {
3385 	struct resource_list_entry *rle = NULL;
3386 	int passthrough = (device_get_parent(child) != bus);
3387 	struct resource *r;
3388 
3389 	if (passthrough)
3390 		panic(
3391     "resource_list_reserve() should only be called for direct children");
3392 	if (flags & RF_ACTIVE)
3393 		panic(
3394     "resource_list_reserve() should only reserve inactive resources");
3395 
3396 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3397 	    flags);
3398 	if (r != NULL) {
3399 		rle = resource_list_find(rl, type, *rid);
3400 		rle->flags |= RLE_RESERVED;
3401 	}
3402 	return (r);
3403 }
3404 
3405 /**
3406  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3407  *
3408  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3409  * and passing the allocation up to the parent of @p bus. This assumes
3410  * that the first entry of @c device_get_ivars(child) is a struct
3411  * resource_list. This also handles 'passthrough' allocations where a
3412  * child is a remote descendant of bus by passing the allocation up to
3413  * the parent of bus.
3414  *
3415  * Typically, a bus driver would store a list of child resources
3416  * somewhere in the child device's ivars (see device_get_ivars()) and
3417  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3418  * then call resource_list_alloc() to perform the allocation.
3419  *
3420  * @param rl		the resource list to allocate from
3421  * @param bus		the parent device of @p child
3422  * @param child		the device which is requesting an allocation
3423  * @param type		the type of resource to allocate
3424  * @param rid		a pointer to the resource identifier
3425  * @param start		hint at the start of the resource range - pass
3426  *			@c 0 for any start address
3427  * @param end		hint at the end of the resource range - pass
3428  *			@c ~0 for any end address
3429  * @param count		hint at the size of range required - pass @c 1
3430  *			for any size
3431  * @param flags		any extra flags to control the resource
3432  *			allocation - see @c RF_XXX flags in
3433  *			<sys/rman.h> for details
3434  *
3435  * @returns		the resource which was allocated or @c NULL if no
3436  *			resource could be allocated
3437  */
3438 struct resource *
3439 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3440     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3441 {
3442 	struct resource_list_entry *rle = NULL;
3443 	int passthrough = (device_get_parent(child) != bus);
3444 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3445 
3446 	if (passthrough) {
3447 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3448 		    type, rid, start, end, count, flags));
3449 	}
3450 
3451 	rle = resource_list_find(rl, type, *rid);
3452 
3453 	if (!rle)
3454 		return (NULL);		/* no resource of that type/rid */
3455 
3456 	if (rle->res) {
3457 		if (rle->flags & RLE_RESERVED) {
3458 			if (rle->flags & RLE_ALLOCATED)
3459 				return (NULL);
3460 			if ((flags & RF_ACTIVE) &&
3461 			    bus_activate_resource(child, type, *rid,
3462 			    rle->res) != 0)
3463 				return (NULL);
3464 			rle->flags |= RLE_ALLOCATED;
3465 			return (rle->res);
3466 		}
3467 		device_printf(bus,
3468 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3469 		    type, device_get_nameunit(child));
3470 		return (NULL);
3471 	}
3472 
3473 	if (isdefault) {
3474 		start = rle->start;
3475 		count = ulmax(count, rle->count);
3476 		end = ulmax(rle->end, start + count - 1);
3477 	}
3478 
3479 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3480 	    type, rid, start, end, count, flags);
3481 
3482 	/*
3483 	 * Record the new range.
3484 	 */
3485 	if (rle->res) {
3486 		rle->start = rman_get_start(rle->res);
3487 		rle->end = rman_get_end(rle->res);
3488 		rle->count = count;
3489 	}
3490 
3491 	return (rle->res);
3492 }
3493 
3494 /**
3495  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3496  *
3497  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3498  * used with resource_list_alloc().
3499  *
3500  * @param rl		the resource list which was allocated from
3501  * @param bus		the parent device of @p child
3502  * @param child		the device which is requesting a release
3503  * @param type		the type of resource to release
3504  * @param rid		the resource identifier
3505  * @param res		the resource to release
3506  *
3507  * @retval 0		success
3508  * @retval non-zero	a standard unix error code indicating what
3509  *			error condition prevented the operation
3510  */
3511 int
3512 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3513     int type, int rid, struct resource *res)
3514 {
3515 	struct resource_list_entry *rle = NULL;
3516 	int passthrough = (device_get_parent(child) != bus);
3517 	int error;
3518 
3519 	if (passthrough) {
3520 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3521 		    type, rid, res));
3522 	}
3523 
3524 	rle = resource_list_find(rl, type, rid);
3525 
3526 	if (!rle)
3527 		panic("resource_list_release: can't find resource");
3528 	if (!rle->res)
3529 		panic("resource_list_release: resource entry is not busy");
3530 	if (rle->flags & RLE_RESERVED) {
3531 		if (rle->flags & RLE_ALLOCATED) {
3532 			if (rman_get_flags(res) & RF_ACTIVE) {
3533 				error = bus_deactivate_resource(child, type,
3534 				    rid, res);
3535 				if (error)
3536 					return (error);
3537 			}
3538 			rle->flags &= ~RLE_ALLOCATED;
3539 			return (0);
3540 		}
3541 		return (EINVAL);
3542 	}
3543 
3544 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3545 	    type, rid, res);
3546 	if (error)
3547 		return (error);
3548 
3549 	rle->res = NULL;
3550 	return (0);
3551 }
3552 
3553 /**
3554  * @brief Release all active resources of a given type
3555  *
3556  * Release all active resources of a specified type.  This is intended
3557  * to be used to cleanup resources leaked by a driver after detach or
3558  * a failed attach.
3559  *
3560  * @param rl		the resource list which was allocated from
3561  * @param bus		the parent device of @p child
3562  * @param child		the device whose active resources are being released
3563  * @param type		the type of resources to release
3564  *
3565  * @retval 0		success
3566  * @retval EBUSY	at least one resource was active
3567  */
3568 int
3569 resource_list_release_active(struct resource_list *rl, device_t bus,
3570     device_t child, int type)
3571 {
3572 	struct resource_list_entry *rle;
3573 	int error, retval;
3574 
3575 	retval = 0;
3576 	STAILQ_FOREACH(rle, rl, link) {
3577 		if (rle->type != type)
3578 			continue;
3579 		if (rle->res == NULL)
3580 			continue;
3581 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3582 		    RLE_RESERVED)
3583 			continue;
3584 		retval = EBUSY;
3585 		error = resource_list_release(rl, bus, child, type,
3586 		    rman_get_rid(rle->res), rle->res);
3587 		if (error != 0)
3588 			device_printf(bus,
3589 			    "Failed to release active resource: %d\n", error);
3590 	}
3591 	return (retval);
3592 }
3593 
3594 
3595 /**
3596  * @brief Fully release a reserved resource
3597  *
3598  * Fully releases a resource reserved via resource_list_reserve().
3599  *
3600  * @param rl		the resource list which was allocated from
3601  * @param bus		the parent device of @p child
3602  * @param child		the device whose reserved resource is being released
3603  * @param type		the type of resource to release
3604  * @param rid		the resource identifier
3605  * @param res		the resource to release
3606  *
3607  * @retval 0		success
3608  * @retval non-zero	a standard unix error code indicating what
3609  *			error condition prevented the operation
3610  */
3611 int
3612 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3613     int type, int rid)
3614 {
3615 	struct resource_list_entry *rle = NULL;
3616 	int passthrough = (device_get_parent(child) != bus);
3617 
3618 	if (passthrough)
3619 		panic(
3620     "resource_list_unreserve() should only be called for direct children");
3621 
3622 	rle = resource_list_find(rl, type, rid);
3623 
3624 	if (!rle)
3625 		panic("resource_list_unreserve: can't find resource");
3626 	if (!(rle->flags & RLE_RESERVED))
3627 		return (EINVAL);
3628 	if (rle->flags & RLE_ALLOCATED)
3629 		return (EBUSY);
3630 	rle->flags &= ~RLE_RESERVED;
3631 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3632 }
3633 
3634 /**
3635  * @brief Print a description of resources in a resource list
3636  *
3637  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3638  * The name is printed if at least one resource of the given type is available.
3639  * The format is used to print resource start and end.
3640  *
3641  * @param rl		the resource list to print
3642  * @param name		the name of @p type, e.g. @c "memory"
3643  * @param type		type type of resource entry to print
3644  * @param format	printf(9) format string to print resource
3645  *			start and end values
3646  *
3647  * @returns		the number of characters printed
3648  */
3649 int
3650 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3651     const char *format)
3652 {
3653 	struct resource_list_entry *rle;
3654 	int printed, retval;
3655 
3656 	printed = 0;
3657 	retval = 0;
3658 	/* Yes, this is kinda cheating */
3659 	STAILQ_FOREACH(rle, rl, link) {
3660 		if (rle->type == type) {
3661 			if (printed == 0)
3662 				retval += printf(" %s ", name);
3663 			else
3664 				retval += printf(",");
3665 			printed++;
3666 			retval += printf(format, rle->start);
3667 			if (rle->count > 1) {
3668 				retval += printf("-");
3669 				retval += printf(format, rle->start +
3670 						 rle->count - 1);
3671 			}
3672 		}
3673 	}
3674 	return (retval);
3675 }
3676 
3677 /**
3678  * @brief Releases all the resources in a list.
3679  *
3680  * @param rl		The resource list to purge.
3681  *
3682  * @returns		nothing
3683  */
3684 void
3685 resource_list_purge(struct resource_list *rl)
3686 {
3687 	struct resource_list_entry *rle;
3688 
3689 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3690 		if (rle->res)
3691 			bus_release_resource(rman_get_device(rle->res),
3692 			    rle->type, rle->rid, rle->res);
3693 		STAILQ_REMOVE_HEAD(rl, link);
3694 		free(rle, M_BUS);
3695 	}
3696 }
3697 
3698 device_t
3699 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3700 {
3701 
3702 	return (device_add_child_ordered(dev, order, name, unit));
3703 }
3704 
3705 /**
3706  * @brief Helper function for implementing DEVICE_PROBE()
3707  *
3708  * This function can be used to help implement the DEVICE_PROBE() for
3709  * a bus (i.e. a device which has other devices attached to it). It
3710  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3711  * devclass.
3712  */
3713 int
3714 bus_generic_probe(device_t dev)
3715 {
3716 	devclass_t dc = dev->devclass;
3717 	driverlink_t dl;
3718 
3719 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3720 		/*
3721 		 * If this driver's pass is too high, then ignore it.
3722 		 * For most drivers in the default pass, this will
3723 		 * never be true.  For early-pass drivers they will
3724 		 * only call the identify routines of eligible drivers
3725 		 * when this routine is called.  Drivers for later
3726 		 * passes should have their identify routines called
3727 		 * on early-pass buses during BUS_NEW_PASS().
3728 		 */
3729 		if (dl->pass > bus_current_pass)
3730 			continue;
3731 		DEVICE_IDENTIFY(dl->driver, dev);
3732 	}
3733 
3734 	return (0);
3735 }
3736 
3737 /**
3738  * @brief Helper function for implementing DEVICE_ATTACH()
3739  *
3740  * This function can be used to help implement the DEVICE_ATTACH() for
3741  * a bus. It calls device_probe_and_attach() for each of the device's
3742  * children.
3743  */
3744 int
3745 bus_generic_attach(device_t dev)
3746 {
3747 	device_t child;
3748 
3749 	TAILQ_FOREACH(child, &dev->children, link) {
3750 		device_probe_and_attach(child);
3751 	}
3752 
3753 	return (0);
3754 }
3755 
3756 /**
3757  * @brief Helper function for delaying attaching children
3758  *
3759  * Many buses can't run transactions on the bus which children need to probe and
3760  * attach until after interrupts and/or timers are running.  This function
3761  * delays their attach until interrupts and timers are enabled.
3762  */
3763 int
3764 bus_delayed_attach_children(device_t dev)
3765 {
3766 	/* Probe and attach the bus children when interrupts are available */
3767 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3768 
3769 	return (0);
3770 }
3771 
3772 /**
3773  * @brief Helper function for implementing DEVICE_DETACH()
3774  *
3775  * This function can be used to help implement the DEVICE_DETACH() for
3776  * a bus. It calls device_detach() for each of the device's
3777  * children.
3778  */
3779 int
3780 bus_generic_detach(device_t dev)
3781 {
3782 	device_t child;
3783 	int error;
3784 
3785 	if (dev->state != DS_ATTACHED)
3786 		return (EBUSY);
3787 
3788 	/*
3789 	 * Detach children in the reverse order.
3790 	 * See bus_generic_suspend for details.
3791 	 */
3792 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3793 		if ((error = device_detach(child)) != 0)
3794 			return (error);
3795 	}
3796 
3797 	return (0);
3798 }
3799 
3800 /**
3801  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3802  *
3803  * This function can be used to help implement the DEVICE_SHUTDOWN()
3804  * for a bus. It calls device_shutdown() for each of the device's
3805  * children.
3806  */
3807 int
3808 bus_generic_shutdown(device_t dev)
3809 {
3810 	device_t child;
3811 
3812 	/*
3813 	 * Shut down children in the reverse order.
3814 	 * See bus_generic_suspend for details.
3815 	 */
3816 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3817 		device_shutdown(child);
3818 	}
3819 
3820 	return (0);
3821 }
3822 
3823 /**
3824  * @brief Default function for suspending a child device.
3825  *
3826  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3827  */
3828 int
3829 bus_generic_suspend_child(device_t dev, device_t child)
3830 {
3831 	int	error;
3832 
3833 	error = DEVICE_SUSPEND(child);
3834 
3835 	if (error == 0)
3836 		child->flags |= DF_SUSPENDED;
3837 
3838 	return (error);
3839 }
3840 
3841 /**
3842  * @brief Default function for resuming a child device.
3843  *
3844  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3845  */
3846 int
3847 bus_generic_resume_child(device_t dev, device_t child)
3848 {
3849 
3850 	DEVICE_RESUME(child);
3851 	child->flags &= ~DF_SUSPENDED;
3852 
3853 	return (0);
3854 }
3855 
3856 /**
3857  * @brief Helper function for implementing DEVICE_SUSPEND()
3858  *
3859  * This function can be used to help implement the DEVICE_SUSPEND()
3860  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3861  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3862  * operation is aborted and any devices which were suspended are
3863  * resumed immediately by calling their DEVICE_RESUME() methods.
3864  */
3865 int
3866 bus_generic_suspend(device_t dev)
3867 {
3868 	int		error;
3869 	device_t	child;
3870 
3871 	/*
3872 	 * Suspend children in the reverse order.
3873 	 * For most buses all children are equal, so the order does not matter.
3874 	 * Other buses, such as acpi, carefully order their child devices to
3875 	 * express implicit dependencies between them.  For such buses it is
3876 	 * safer to bring down devices in the reverse order.
3877 	 */
3878 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3879 		error = BUS_SUSPEND_CHILD(dev, child);
3880 		if (error != 0) {
3881 			child = TAILQ_NEXT(child, link);
3882 			if (child != NULL) {
3883 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3884 					BUS_RESUME_CHILD(dev, child);
3885 			}
3886 			return (error);
3887 		}
3888 	}
3889 	return (0);
3890 }
3891 
3892 /**
3893  * @brief Helper function for implementing DEVICE_RESUME()
3894  *
3895  * This function can be used to help implement the DEVICE_RESUME() for
3896  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3897  */
3898 int
3899 bus_generic_resume(device_t dev)
3900 {
3901 	device_t	child;
3902 
3903 	TAILQ_FOREACH(child, &dev->children, link) {
3904 		BUS_RESUME_CHILD(dev, child);
3905 		/* if resume fails, there's nothing we can usefully do... */
3906 	}
3907 	return (0);
3908 }
3909 
3910 
3911 /**
3912  * @brief Helper function for implementing BUS_RESET_POST
3913  *
3914  * Bus can use this function to implement common operations of
3915  * re-attaching or resuming the children after the bus itself was
3916  * reset, and after restoring bus-unique state of children.
3917  *
3918  * @param dev	The bus
3919  * #param flags	DEVF_RESET_*
3920  */
3921 int
3922 bus_helper_reset_post(device_t dev, int flags)
3923 {
3924 	device_t child;
3925 	int error, error1;
3926 
3927 	error = 0;
3928 	TAILQ_FOREACH(child, &dev->children,link) {
3929 		BUS_RESET_POST(dev, child);
3930 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3931 		    device_probe_and_attach(child) :
3932 		    BUS_RESUME_CHILD(dev, child);
3933 		if (error == 0 && error1 != 0)
3934 			error = error1;
3935 	}
3936 	return (error);
3937 }
3938 
3939 static void
3940 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3941 {
3942 
3943 	child = TAILQ_NEXT(child, link);
3944 	if (child == NULL)
3945 		return;
3946 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3947 		BUS_RESET_POST(dev, child);
3948 		if ((flags & DEVF_RESET_DETACH) != 0)
3949 			device_probe_and_attach(child);
3950 		else
3951 			BUS_RESUME_CHILD(dev, child);
3952 	}
3953 }
3954 
3955 /**
3956  * @brief Helper function for implementing BUS_RESET_PREPARE
3957  *
3958  * Bus can use this function to implement common operations of
3959  * detaching or suspending the children before the bus itself is
3960  * reset, and then save bus-unique state of children that must
3961  * persists around reset.
3962  *
3963  * @param dev	The bus
3964  * #param flags	DEVF_RESET_*
3965  */
3966 int
3967 bus_helper_reset_prepare(device_t dev, int flags)
3968 {
3969 	device_t child;
3970 	int error;
3971 
3972 	if (dev->state != DS_ATTACHED)
3973 		return (EBUSY);
3974 
3975 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3976 		if ((flags & DEVF_RESET_DETACH) != 0) {
3977 			error = device_get_state(child) == DS_ATTACHED ?
3978 			    device_detach(child) : 0;
3979 		} else {
3980 			error = BUS_SUSPEND_CHILD(dev, child);
3981 		}
3982 		if (error == 0) {
3983 			error = BUS_RESET_PREPARE(dev, child);
3984 			if (error != 0) {
3985 				if ((flags & DEVF_RESET_DETACH) != 0)
3986 					device_probe_and_attach(child);
3987 				else
3988 					BUS_RESUME_CHILD(dev, child);
3989 			}
3990 		}
3991 		if (error != 0) {
3992 			bus_helper_reset_prepare_rollback(dev, child, flags);
3993 			return (error);
3994 		}
3995 	}
3996 	return (0);
3997 }
3998 
3999 /**
4000  * @brief Helper function for implementing BUS_PRINT_CHILD().
4001  *
4002  * This function prints the first part of the ascii representation of
4003  * @p child, including its name, unit and description (if any - see
4004  * device_set_desc()).
4005  *
4006  * @returns the number of characters printed
4007  */
4008 int
4009 bus_print_child_header(device_t dev, device_t child)
4010 {
4011 	int	retval = 0;
4012 
4013 	if (device_get_desc(child)) {
4014 		retval += device_printf(child, "<%s>", device_get_desc(child));
4015 	} else {
4016 		retval += printf("%s", device_get_nameunit(child));
4017 	}
4018 
4019 	return (retval);
4020 }
4021 
4022 /**
4023  * @brief Helper function for implementing BUS_PRINT_CHILD().
4024  *
4025  * This function prints the last part of the ascii representation of
4026  * @p child, which consists of the string @c " on " followed by the
4027  * name and unit of the @p dev.
4028  *
4029  * @returns the number of characters printed
4030  */
4031 int
4032 bus_print_child_footer(device_t dev, device_t child)
4033 {
4034 	return (printf(" on %s\n", device_get_nameunit(dev)));
4035 }
4036 
4037 /**
4038  * @brief Helper function for implementing BUS_PRINT_CHILD().
4039  *
4040  * This function prints out the VM domain for the given device.
4041  *
4042  * @returns the number of characters printed
4043  */
4044 int
4045 bus_print_child_domain(device_t dev, device_t child)
4046 {
4047 	int domain;
4048 
4049 	/* No domain? Don't print anything */
4050 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4051 		return (0);
4052 
4053 	return (printf(" numa-domain %d", domain));
4054 }
4055 
4056 /**
4057  * @brief Helper function for implementing BUS_PRINT_CHILD().
4058  *
4059  * This function simply calls bus_print_child_header() followed by
4060  * bus_print_child_footer().
4061  *
4062  * @returns the number of characters printed
4063  */
4064 int
4065 bus_generic_print_child(device_t dev, device_t child)
4066 {
4067 	int	retval = 0;
4068 
4069 	retval += bus_print_child_header(dev, child);
4070 	retval += bus_print_child_domain(dev, child);
4071 	retval += bus_print_child_footer(dev, child);
4072 
4073 	return (retval);
4074 }
4075 
4076 /**
4077  * @brief Stub function for implementing BUS_READ_IVAR().
4078  *
4079  * @returns ENOENT
4080  */
4081 int
4082 bus_generic_read_ivar(device_t dev, device_t child, int index,
4083     uintptr_t * result)
4084 {
4085 	return (ENOENT);
4086 }
4087 
4088 /**
4089  * @brief Stub function for implementing BUS_WRITE_IVAR().
4090  *
4091  * @returns ENOENT
4092  */
4093 int
4094 bus_generic_write_ivar(device_t dev, device_t child, int index,
4095     uintptr_t value)
4096 {
4097 	return (ENOENT);
4098 }
4099 
4100 /**
4101  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4102  *
4103  * @returns NULL
4104  */
4105 struct resource_list *
4106 bus_generic_get_resource_list(device_t dev, device_t child)
4107 {
4108 	return (NULL);
4109 }
4110 
4111 /**
4112  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4113  *
4114  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4115  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4116  * and then calls device_probe_and_attach() for each unattached child.
4117  */
4118 void
4119 bus_generic_driver_added(device_t dev, driver_t *driver)
4120 {
4121 	device_t child;
4122 
4123 	DEVICE_IDENTIFY(driver, dev);
4124 	TAILQ_FOREACH(child, &dev->children, link) {
4125 		if (child->state == DS_NOTPRESENT ||
4126 		    (child->flags & DF_REBID))
4127 			device_probe_and_attach(child);
4128 	}
4129 }
4130 
4131 /**
4132  * @brief Helper function for implementing BUS_NEW_PASS().
4133  *
4134  * This implementing of BUS_NEW_PASS() first calls the identify
4135  * routines for any drivers that probe at the current pass.  Then it
4136  * walks the list of devices for this bus.  If a device is already
4137  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4138  * device is not already attached, it attempts to attach a driver to
4139  * it.
4140  */
4141 void
4142 bus_generic_new_pass(device_t dev)
4143 {
4144 	driverlink_t dl;
4145 	devclass_t dc;
4146 	device_t child;
4147 
4148 	dc = dev->devclass;
4149 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4150 		if (dl->pass == bus_current_pass)
4151 			DEVICE_IDENTIFY(dl->driver, dev);
4152 	}
4153 	TAILQ_FOREACH(child, &dev->children, link) {
4154 		if (child->state >= DS_ATTACHED)
4155 			BUS_NEW_PASS(child);
4156 		else if (child->state == DS_NOTPRESENT)
4157 			device_probe_and_attach(child);
4158 	}
4159 }
4160 
4161 /**
4162  * @brief Helper function for implementing BUS_SETUP_INTR().
4163  *
4164  * This simple implementation of BUS_SETUP_INTR() simply calls the
4165  * BUS_SETUP_INTR() method of the parent of @p dev.
4166  */
4167 int
4168 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4169     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4170     void **cookiep)
4171 {
4172 	/* Propagate up the bus hierarchy until someone handles it. */
4173 	if (dev->parent)
4174 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4175 		    filter, intr, arg, cookiep));
4176 	return (EINVAL);
4177 }
4178 
4179 /**
4180  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4181  *
4182  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4183  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4184  */
4185 int
4186 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4187     void *cookie)
4188 {
4189 	/* Propagate up the bus hierarchy until someone handles it. */
4190 	if (dev->parent)
4191 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4192 	return (EINVAL);
4193 }
4194 
4195 /**
4196  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4197  *
4198  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4199  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4200  */
4201 int
4202 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4203 {
4204 	/* Propagate up the bus hierarchy until someone handles it. */
4205 	if (dev->parent)
4206 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4207 	return (EINVAL);
4208 }
4209 
4210 /**
4211  * @brief Helper function for implementing BUS_RESUME_INTR().
4212  *
4213  * This simple implementation of BUS_RESUME_INTR() simply calls the
4214  * BUS_RESUME_INTR() method of the parent of @p dev.
4215  */
4216 int
4217 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4218 {
4219 	/* Propagate up the bus hierarchy until someone handles it. */
4220 	if (dev->parent)
4221 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4222 	return (EINVAL);
4223 }
4224 
4225 /**
4226  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4227  *
4228  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4229  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4230  */
4231 int
4232 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4233     struct resource *r, rman_res_t start, rman_res_t end)
4234 {
4235 	/* Propagate up the bus hierarchy until someone handles it. */
4236 	if (dev->parent)
4237 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4238 		    end));
4239 	return (EINVAL);
4240 }
4241 
4242 /**
4243  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4244  *
4245  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4246  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4247  */
4248 struct resource *
4249 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4250     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4251 {
4252 	/* Propagate up the bus hierarchy until someone handles it. */
4253 	if (dev->parent)
4254 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4255 		    start, end, count, flags));
4256 	return (NULL);
4257 }
4258 
4259 /**
4260  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4261  *
4262  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4263  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4264  */
4265 int
4266 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4267     struct resource *r)
4268 {
4269 	/* Propagate up the bus hierarchy until someone handles it. */
4270 	if (dev->parent)
4271 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4272 		    r));
4273 	return (EINVAL);
4274 }
4275 
4276 /**
4277  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4278  *
4279  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4280  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4281  */
4282 int
4283 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4284     struct resource *r)
4285 {
4286 	/* Propagate up the bus hierarchy until someone handles it. */
4287 	if (dev->parent)
4288 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4289 		    r));
4290 	return (EINVAL);
4291 }
4292 
4293 /**
4294  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4295  *
4296  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4297  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4298  */
4299 int
4300 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4301     int rid, struct resource *r)
4302 {
4303 	/* Propagate up the bus hierarchy until someone handles it. */
4304 	if (dev->parent)
4305 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4306 		    r));
4307 	return (EINVAL);
4308 }
4309 
4310 /**
4311  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4312  *
4313  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4314  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4315  */
4316 int
4317 bus_generic_map_resource(device_t dev, device_t child, int type,
4318     struct resource *r, struct resource_map_request *args,
4319     struct resource_map *map)
4320 {
4321 	/* Propagate up the bus hierarchy until someone handles it. */
4322 	if (dev->parent)
4323 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4324 		    map));
4325 	return (EINVAL);
4326 }
4327 
4328 /**
4329  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4330  *
4331  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4332  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4333  */
4334 int
4335 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4336     struct resource *r, struct resource_map *map)
4337 {
4338 	/* Propagate up the bus hierarchy until someone handles it. */
4339 	if (dev->parent)
4340 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4341 	return (EINVAL);
4342 }
4343 
4344 /**
4345  * @brief Helper function for implementing BUS_BIND_INTR().
4346  *
4347  * This simple implementation of BUS_BIND_INTR() simply calls the
4348  * BUS_BIND_INTR() method of the parent of @p dev.
4349  */
4350 int
4351 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4352     int cpu)
4353 {
4354 
4355 	/* Propagate up the bus hierarchy until someone handles it. */
4356 	if (dev->parent)
4357 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4358 	return (EINVAL);
4359 }
4360 
4361 /**
4362  * @brief Helper function for implementing BUS_CONFIG_INTR().
4363  *
4364  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4365  * BUS_CONFIG_INTR() method of the parent of @p dev.
4366  */
4367 int
4368 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4369     enum intr_polarity pol)
4370 {
4371 
4372 	/* Propagate up the bus hierarchy until someone handles it. */
4373 	if (dev->parent)
4374 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4375 	return (EINVAL);
4376 }
4377 
4378 /**
4379  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4380  *
4381  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4382  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4383  */
4384 int
4385 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4386     void *cookie, const char *descr)
4387 {
4388 
4389 	/* Propagate up the bus hierarchy until someone handles it. */
4390 	if (dev->parent)
4391 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4392 		    descr));
4393 	return (EINVAL);
4394 }
4395 
4396 /**
4397  * @brief Helper function for implementing BUS_GET_CPUS().
4398  *
4399  * This simple implementation of BUS_GET_CPUS() simply calls the
4400  * BUS_GET_CPUS() method of the parent of @p dev.
4401  */
4402 int
4403 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4404     size_t setsize, cpuset_t *cpuset)
4405 {
4406 
4407 	/* Propagate up the bus hierarchy until someone handles it. */
4408 	if (dev->parent != NULL)
4409 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4410 	return (EINVAL);
4411 }
4412 
4413 /**
4414  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4415  *
4416  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4417  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4418  */
4419 bus_dma_tag_t
4420 bus_generic_get_dma_tag(device_t dev, device_t child)
4421 {
4422 
4423 	/* Propagate up the bus hierarchy until someone handles it. */
4424 	if (dev->parent != NULL)
4425 		return (BUS_GET_DMA_TAG(dev->parent, child));
4426 	return (NULL);
4427 }
4428 
4429 /**
4430  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4431  *
4432  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4433  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4434  */
4435 bus_space_tag_t
4436 bus_generic_get_bus_tag(device_t dev, device_t child)
4437 {
4438 
4439 	/* Propagate up the bus hierarchy until someone handles it. */
4440 	if (dev->parent != NULL)
4441 		return (BUS_GET_BUS_TAG(dev->parent, child));
4442 	return ((bus_space_tag_t)0);
4443 }
4444 
4445 /**
4446  * @brief Helper function for implementing BUS_GET_RESOURCE().
4447  *
4448  * This implementation of BUS_GET_RESOURCE() uses the
4449  * resource_list_find() function to do most of the work. It calls
4450  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4451  * search.
4452  */
4453 int
4454 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4455     rman_res_t *startp, rman_res_t *countp)
4456 {
4457 	struct resource_list *		rl = NULL;
4458 	struct resource_list_entry *	rle = NULL;
4459 
4460 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4461 	if (!rl)
4462 		return (EINVAL);
4463 
4464 	rle = resource_list_find(rl, type, rid);
4465 	if (!rle)
4466 		return (ENOENT);
4467 
4468 	if (startp)
4469 		*startp = rle->start;
4470 	if (countp)
4471 		*countp = rle->count;
4472 
4473 	return (0);
4474 }
4475 
4476 /**
4477  * @brief Helper function for implementing BUS_SET_RESOURCE().
4478  *
4479  * This implementation of BUS_SET_RESOURCE() uses the
4480  * resource_list_add() function to do most of the work. It calls
4481  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4482  * edit.
4483  */
4484 int
4485 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4486     rman_res_t start, rman_res_t count)
4487 {
4488 	struct resource_list *		rl = NULL;
4489 
4490 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4491 	if (!rl)
4492 		return (EINVAL);
4493 
4494 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4495 
4496 	return (0);
4497 }
4498 
4499 /**
4500  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4501  *
4502  * This implementation of BUS_DELETE_RESOURCE() uses the
4503  * resource_list_delete() function to do most of the work. It calls
4504  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4505  * edit.
4506  */
4507 void
4508 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4509 {
4510 	struct resource_list *		rl = NULL;
4511 
4512 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4513 	if (!rl)
4514 		return;
4515 
4516 	resource_list_delete(rl, type, rid);
4517 
4518 	return;
4519 }
4520 
4521 /**
4522  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4523  *
4524  * This implementation of BUS_RELEASE_RESOURCE() uses the
4525  * resource_list_release() function to do most of the work. It calls
4526  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4527  */
4528 int
4529 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4530     int rid, struct resource *r)
4531 {
4532 	struct resource_list *		rl = NULL;
4533 
4534 	if (device_get_parent(child) != dev)
4535 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4536 		    type, rid, r));
4537 
4538 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4539 	if (!rl)
4540 		return (EINVAL);
4541 
4542 	return (resource_list_release(rl, dev, child, type, rid, r));
4543 }
4544 
4545 /**
4546  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4547  *
4548  * This implementation of BUS_ALLOC_RESOURCE() uses the
4549  * resource_list_alloc() function to do most of the work. It calls
4550  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4551  */
4552 struct resource *
4553 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4554     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4555 {
4556 	struct resource_list *		rl = NULL;
4557 
4558 	if (device_get_parent(child) != dev)
4559 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4560 		    type, rid, start, end, count, flags));
4561 
4562 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4563 	if (!rl)
4564 		return (NULL);
4565 
4566 	return (resource_list_alloc(rl, dev, child, type, rid,
4567 	    start, end, count, flags));
4568 }
4569 
4570 /**
4571  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4572  *
4573  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4574  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4575  */
4576 int
4577 bus_generic_child_present(device_t dev, device_t child)
4578 {
4579 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4580 }
4581 
4582 int
4583 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4584 {
4585 
4586 	if (dev->parent)
4587 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4588 
4589 	return (ENOENT);
4590 }
4591 
4592 /**
4593  * @brief Helper function for implementing BUS_RESCAN().
4594  *
4595  * This null implementation of BUS_RESCAN() always fails to indicate
4596  * the bus does not support rescanning.
4597  */
4598 int
4599 bus_null_rescan(device_t dev)
4600 {
4601 
4602 	return (ENXIO);
4603 }
4604 
4605 /*
4606  * Some convenience functions to make it easier for drivers to use the
4607  * resource-management functions.  All these really do is hide the
4608  * indirection through the parent's method table, making for slightly
4609  * less-wordy code.  In the future, it might make sense for this code
4610  * to maintain some sort of a list of resources allocated by each device.
4611  */
4612 
4613 int
4614 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4615     struct resource **res)
4616 {
4617 	int i;
4618 
4619 	for (i = 0; rs[i].type != -1; i++)
4620 		res[i] = NULL;
4621 	for (i = 0; rs[i].type != -1; i++) {
4622 		res[i] = bus_alloc_resource_any(dev,
4623 		    rs[i].type, &rs[i].rid, rs[i].flags);
4624 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4625 			bus_release_resources(dev, rs, res);
4626 			return (ENXIO);
4627 		}
4628 	}
4629 	return (0);
4630 }
4631 
4632 void
4633 bus_release_resources(device_t dev, const struct resource_spec *rs,
4634     struct resource **res)
4635 {
4636 	int i;
4637 
4638 	for (i = 0; rs[i].type != -1; i++)
4639 		if (res[i] != NULL) {
4640 			bus_release_resource(
4641 			    dev, rs[i].type, rs[i].rid, res[i]);
4642 			res[i] = NULL;
4643 		}
4644 }
4645 
4646 /**
4647  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4648  *
4649  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4650  * parent of @p dev.
4651  */
4652 struct resource *
4653 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4654     rman_res_t end, rman_res_t count, u_int flags)
4655 {
4656 	struct resource *res;
4657 
4658 	if (dev->parent == NULL)
4659 		return (NULL);
4660 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4661 	    count, flags);
4662 	return (res);
4663 }
4664 
4665 /**
4666  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4667  *
4668  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4669  * parent of @p dev.
4670  */
4671 int
4672 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4673     rman_res_t end)
4674 {
4675 	if (dev->parent == NULL)
4676 		return (EINVAL);
4677 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4678 }
4679 
4680 /**
4681  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4682  *
4683  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4684  * parent of @p dev.
4685  */
4686 int
4687 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4688 {
4689 	if (dev->parent == NULL)
4690 		return (EINVAL);
4691 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4692 }
4693 
4694 /**
4695  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4696  *
4697  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4698  * parent of @p dev.
4699  */
4700 int
4701 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4702 {
4703 	if (dev->parent == NULL)
4704 		return (EINVAL);
4705 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4706 }
4707 
4708 /**
4709  * @brief Wrapper function for BUS_MAP_RESOURCE().
4710  *
4711  * This function simply calls the BUS_MAP_RESOURCE() method of the
4712  * parent of @p dev.
4713  */
4714 int
4715 bus_map_resource(device_t dev, int type, struct resource *r,
4716     struct resource_map_request *args, struct resource_map *map)
4717 {
4718 	if (dev->parent == NULL)
4719 		return (EINVAL);
4720 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4721 }
4722 
4723 /**
4724  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4725  *
4726  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4727  * parent of @p dev.
4728  */
4729 int
4730 bus_unmap_resource(device_t dev, int type, struct resource *r,
4731     struct resource_map *map)
4732 {
4733 	if (dev->parent == NULL)
4734 		return (EINVAL);
4735 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4736 }
4737 
4738 /**
4739  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4740  *
4741  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4742  * parent of @p dev.
4743  */
4744 int
4745 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4746 {
4747 	int rv;
4748 
4749 	if (dev->parent == NULL)
4750 		return (EINVAL);
4751 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4752 	return (rv);
4753 }
4754 
4755 /**
4756  * @brief Wrapper function for BUS_SETUP_INTR().
4757  *
4758  * This function simply calls the BUS_SETUP_INTR() method of the
4759  * parent of @p dev.
4760  */
4761 int
4762 bus_setup_intr(device_t dev, struct resource *r, int flags,
4763     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4764 {
4765 	int error;
4766 
4767 	if (dev->parent == NULL)
4768 		return (EINVAL);
4769 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4770 	    arg, cookiep);
4771 	if (error != 0)
4772 		return (error);
4773 	if (handler != NULL && !(flags & INTR_MPSAFE))
4774 		device_printf(dev, "[GIANT-LOCKED]\n");
4775 	return (0);
4776 }
4777 
4778 /**
4779  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4780  *
4781  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4782  * parent of @p dev.
4783  */
4784 int
4785 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4786 {
4787 	if (dev->parent == NULL)
4788 		return (EINVAL);
4789 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4790 }
4791 
4792 /**
4793  * @brief Wrapper function for BUS_SUSPEND_INTR().
4794  *
4795  * This function simply calls the BUS_SUSPEND_INTR() method of the
4796  * parent of @p dev.
4797  */
4798 int
4799 bus_suspend_intr(device_t dev, struct resource *r)
4800 {
4801 	if (dev->parent == NULL)
4802 		return (EINVAL);
4803 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4804 }
4805 
4806 /**
4807  * @brief Wrapper function for BUS_RESUME_INTR().
4808  *
4809  * This function simply calls the BUS_RESUME_INTR() method of the
4810  * parent of @p dev.
4811  */
4812 int
4813 bus_resume_intr(device_t dev, struct resource *r)
4814 {
4815 	if (dev->parent == NULL)
4816 		return (EINVAL);
4817 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4818 }
4819 
4820 /**
4821  * @brief Wrapper function for BUS_BIND_INTR().
4822  *
4823  * This function simply calls the BUS_BIND_INTR() method of the
4824  * parent of @p dev.
4825  */
4826 int
4827 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4828 {
4829 	if (dev->parent == NULL)
4830 		return (EINVAL);
4831 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4832 }
4833 
4834 /**
4835  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4836  *
4837  * This function first formats the requested description into a
4838  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4839  * the parent of @p dev.
4840  */
4841 int
4842 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4843     const char *fmt, ...)
4844 {
4845 	va_list ap;
4846 	char descr[MAXCOMLEN + 1];
4847 
4848 	if (dev->parent == NULL)
4849 		return (EINVAL);
4850 	va_start(ap, fmt);
4851 	vsnprintf(descr, sizeof(descr), fmt, ap);
4852 	va_end(ap);
4853 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4854 }
4855 
4856 /**
4857  * @brief Wrapper function for BUS_SET_RESOURCE().
4858  *
4859  * This function simply calls the BUS_SET_RESOURCE() method of the
4860  * parent of @p dev.
4861  */
4862 int
4863 bus_set_resource(device_t dev, int type, int rid,
4864     rman_res_t start, rman_res_t count)
4865 {
4866 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4867 	    start, count));
4868 }
4869 
4870 /**
4871  * @brief Wrapper function for BUS_GET_RESOURCE().
4872  *
4873  * This function simply calls the BUS_GET_RESOURCE() method of the
4874  * parent of @p dev.
4875  */
4876 int
4877 bus_get_resource(device_t dev, int type, int rid,
4878     rman_res_t *startp, rman_res_t *countp)
4879 {
4880 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4881 	    startp, countp));
4882 }
4883 
4884 /**
4885  * @brief Wrapper function for BUS_GET_RESOURCE().
4886  *
4887  * This function simply calls the BUS_GET_RESOURCE() method of the
4888  * parent of @p dev and returns the start value.
4889  */
4890 rman_res_t
4891 bus_get_resource_start(device_t dev, int type, int rid)
4892 {
4893 	rman_res_t start;
4894 	rman_res_t count;
4895 	int error;
4896 
4897 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4898 	    &start, &count);
4899 	if (error)
4900 		return (0);
4901 	return (start);
4902 }
4903 
4904 /**
4905  * @brief Wrapper function for BUS_GET_RESOURCE().
4906  *
4907  * This function simply calls the BUS_GET_RESOURCE() method of the
4908  * parent of @p dev and returns the count value.
4909  */
4910 rman_res_t
4911 bus_get_resource_count(device_t dev, int type, int rid)
4912 {
4913 	rman_res_t start;
4914 	rman_res_t count;
4915 	int error;
4916 
4917 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4918 	    &start, &count);
4919 	if (error)
4920 		return (0);
4921 	return (count);
4922 }
4923 
4924 /**
4925  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4926  *
4927  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4928  * parent of @p dev.
4929  */
4930 void
4931 bus_delete_resource(device_t dev, int type, int rid)
4932 {
4933 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4934 }
4935 
4936 /**
4937  * @brief Wrapper function for BUS_CHILD_PRESENT().
4938  *
4939  * This function simply calls the BUS_CHILD_PRESENT() method of the
4940  * parent of @p dev.
4941  */
4942 int
4943 bus_child_present(device_t child)
4944 {
4945 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4946 }
4947 
4948 /**
4949  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4950  *
4951  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4952  * parent of @p dev.
4953  */
4954 int
4955 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4956 {
4957 	device_t parent;
4958 
4959 	parent = device_get_parent(child);
4960 	if (parent == NULL) {
4961 		*buf = '\0';
4962 		return (0);
4963 	}
4964 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4965 }
4966 
4967 /**
4968  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4969  *
4970  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4971  * parent of @p dev.
4972  */
4973 int
4974 bus_child_location_str(device_t child, char *buf, size_t buflen)
4975 {
4976 	device_t parent;
4977 
4978 	parent = device_get_parent(child);
4979 	if (parent == NULL) {
4980 		*buf = '\0';
4981 		return (0);
4982 	}
4983 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4984 }
4985 
4986 /**
4987  * @brief Wrapper function for BUS_GET_CPUS().
4988  *
4989  * This function simply calls the BUS_GET_CPUS() method of the
4990  * parent of @p dev.
4991  */
4992 int
4993 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
4994 {
4995 	device_t parent;
4996 
4997 	parent = device_get_parent(dev);
4998 	if (parent == NULL)
4999 		return (EINVAL);
5000 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5001 }
5002 
5003 /**
5004  * @brief Wrapper function for BUS_GET_DMA_TAG().
5005  *
5006  * This function simply calls the BUS_GET_DMA_TAG() method of the
5007  * parent of @p dev.
5008  */
5009 bus_dma_tag_t
5010 bus_get_dma_tag(device_t dev)
5011 {
5012 	device_t parent;
5013 
5014 	parent = device_get_parent(dev);
5015 	if (parent == NULL)
5016 		return (NULL);
5017 	return (BUS_GET_DMA_TAG(parent, dev));
5018 }
5019 
5020 /**
5021  * @brief Wrapper function for BUS_GET_BUS_TAG().
5022  *
5023  * This function simply calls the BUS_GET_BUS_TAG() method of the
5024  * parent of @p dev.
5025  */
5026 bus_space_tag_t
5027 bus_get_bus_tag(device_t dev)
5028 {
5029 	device_t parent;
5030 
5031 	parent = device_get_parent(dev);
5032 	if (parent == NULL)
5033 		return ((bus_space_tag_t)0);
5034 	return (BUS_GET_BUS_TAG(parent, dev));
5035 }
5036 
5037 /**
5038  * @brief Wrapper function for BUS_GET_DOMAIN().
5039  *
5040  * This function simply calls the BUS_GET_DOMAIN() method of the
5041  * parent of @p dev.
5042  */
5043 int
5044 bus_get_domain(device_t dev, int *domain)
5045 {
5046 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5047 }
5048 
5049 /* Resume all devices and then notify userland that we're up again. */
5050 static int
5051 root_resume(device_t dev)
5052 {
5053 	int error;
5054 
5055 	error = bus_generic_resume(dev);
5056 	if (error == 0)
5057 		devctl_notify("kern", "power", "resume", NULL);
5058 	return (error);
5059 }
5060 
5061 static int
5062 root_print_child(device_t dev, device_t child)
5063 {
5064 	int	retval = 0;
5065 
5066 	retval += bus_print_child_header(dev, child);
5067 	retval += printf("\n");
5068 
5069 	return (retval);
5070 }
5071 
5072 static int
5073 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5074     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5075 {
5076 	/*
5077 	 * If an interrupt mapping gets to here something bad has happened.
5078 	 */
5079 	panic("root_setup_intr");
5080 }
5081 
5082 /*
5083  * If we get here, assume that the device is permanent and really is
5084  * present in the system.  Removable bus drivers are expected to intercept
5085  * this call long before it gets here.  We return -1 so that drivers that
5086  * really care can check vs -1 or some ERRNO returned higher in the food
5087  * chain.
5088  */
5089 static int
5090 root_child_present(device_t dev, device_t child)
5091 {
5092 	return (-1);
5093 }
5094 
5095 static int
5096 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5097     cpuset_t *cpuset)
5098 {
5099 
5100 	switch (op) {
5101 	case INTR_CPUS:
5102 		/* Default to returning the set of all CPUs. */
5103 		if (setsize != sizeof(cpuset_t))
5104 			return (EINVAL);
5105 		*cpuset = all_cpus;
5106 		return (0);
5107 	default:
5108 		return (EINVAL);
5109 	}
5110 }
5111 
5112 static kobj_method_t root_methods[] = {
5113 	/* Device interface */
5114 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5115 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5116 	KOBJMETHOD(device_resume,	root_resume),
5117 
5118 	/* Bus interface */
5119 	KOBJMETHOD(bus_print_child,	root_print_child),
5120 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5121 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5122 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5123 	KOBJMETHOD(bus_child_present,	root_child_present),
5124 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5125 
5126 	KOBJMETHOD_END
5127 };
5128 
5129 static driver_t root_driver = {
5130 	"root",
5131 	root_methods,
5132 	1,			/* no softc */
5133 };
5134 
5135 device_t	root_bus;
5136 devclass_t	root_devclass;
5137 
5138 static int
5139 root_bus_module_handler(module_t mod, int what, void* arg)
5140 {
5141 	switch (what) {
5142 	case MOD_LOAD:
5143 		TAILQ_INIT(&bus_data_devices);
5144 		kobj_class_compile((kobj_class_t) &root_driver);
5145 		root_bus = make_device(NULL, "root", 0);
5146 		root_bus->desc = "System root bus";
5147 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5148 		root_bus->driver = &root_driver;
5149 		root_bus->state = DS_ATTACHED;
5150 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5151 		devinit();
5152 		return (0);
5153 
5154 	case MOD_SHUTDOWN:
5155 		device_shutdown(root_bus);
5156 		return (0);
5157 	default:
5158 		return (EOPNOTSUPP);
5159 	}
5160 
5161 	return (0);
5162 }
5163 
5164 static moduledata_t root_bus_mod = {
5165 	"rootbus",
5166 	root_bus_module_handler,
5167 	NULL
5168 };
5169 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5170 
5171 /**
5172  * @brief Automatically configure devices
5173  *
5174  * This function begins the autoconfiguration process by calling
5175  * device_probe_and_attach() for each child of the @c root0 device.
5176  */
5177 void
5178 root_bus_configure(void)
5179 {
5180 
5181 	PDEBUG(("."));
5182 
5183 	/* Eventually this will be split up, but this is sufficient for now. */
5184 	bus_set_pass(BUS_PASS_DEFAULT);
5185 }
5186 
5187 /**
5188  * @brief Module handler for registering device drivers
5189  *
5190  * This module handler is used to automatically register device
5191  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5192  * devclass_add_driver() for the driver described by the
5193  * driver_module_data structure pointed to by @p arg
5194  */
5195 int
5196 driver_module_handler(module_t mod, int what, void *arg)
5197 {
5198 	struct driver_module_data *dmd;
5199 	devclass_t bus_devclass;
5200 	kobj_class_t driver;
5201 	int error, pass;
5202 
5203 	dmd = (struct driver_module_data *)arg;
5204 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5205 	error = 0;
5206 
5207 	switch (what) {
5208 	case MOD_LOAD:
5209 		if (dmd->dmd_chainevh)
5210 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5211 
5212 		pass = dmd->dmd_pass;
5213 		driver = dmd->dmd_driver;
5214 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5215 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5216 		error = devclass_add_driver(bus_devclass, driver, pass,
5217 		    dmd->dmd_devclass);
5218 		break;
5219 
5220 	case MOD_UNLOAD:
5221 		PDEBUG(("Unloading module: driver %s from bus %s",
5222 		    DRIVERNAME(dmd->dmd_driver),
5223 		    dmd->dmd_busname));
5224 		error = devclass_delete_driver(bus_devclass,
5225 		    dmd->dmd_driver);
5226 
5227 		if (!error && dmd->dmd_chainevh)
5228 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5229 		break;
5230 	case MOD_QUIESCE:
5231 		PDEBUG(("Quiesce module: driver %s from bus %s",
5232 		    DRIVERNAME(dmd->dmd_driver),
5233 		    dmd->dmd_busname));
5234 		error = devclass_quiesce_driver(bus_devclass,
5235 		    dmd->dmd_driver);
5236 
5237 		if (!error && dmd->dmd_chainevh)
5238 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5239 		break;
5240 	default:
5241 		error = EOPNOTSUPP;
5242 		break;
5243 	}
5244 
5245 	return (error);
5246 }
5247 
5248 /**
5249  * @brief Enumerate all hinted devices for this bus.
5250  *
5251  * Walks through the hints for this bus and calls the bus_hinted_child
5252  * routine for each one it fines.  It searches first for the specific
5253  * bus that's being probed for hinted children (eg isa0), and then for
5254  * generic children (eg isa).
5255  *
5256  * @param	dev	bus device to enumerate
5257  */
5258 void
5259 bus_enumerate_hinted_children(device_t bus)
5260 {
5261 	int i;
5262 	const char *dname, *busname;
5263 	int dunit;
5264 
5265 	/*
5266 	 * enumerate all devices on the specific bus
5267 	 */
5268 	busname = device_get_nameunit(bus);
5269 	i = 0;
5270 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5271 		BUS_HINTED_CHILD(bus, dname, dunit);
5272 
5273 	/*
5274 	 * and all the generic ones.
5275 	 */
5276 	busname = device_get_name(bus);
5277 	i = 0;
5278 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5279 		BUS_HINTED_CHILD(bus, dname, dunit);
5280 }
5281 
5282 #ifdef BUS_DEBUG
5283 
5284 /* the _short versions avoid iteration by not calling anything that prints
5285  * more than oneliners. I love oneliners.
5286  */
5287 
5288 static void
5289 print_device_short(device_t dev, int indent)
5290 {
5291 	if (!dev)
5292 		return;
5293 
5294 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5295 	    dev->unit, dev->desc,
5296 	    (dev->parent? "":"no "),
5297 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5298 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5299 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5300 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5301 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5302 	    (dev->flags&DF_REBID? "rebiddable,":""),
5303 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5304 	    (dev->ivars? "":"no "),
5305 	    (dev->softc? "":"no "),
5306 	    dev->busy));
5307 }
5308 
5309 static void
5310 print_device(device_t dev, int indent)
5311 {
5312 	if (!dev)
5313 		return;
5314 
5315 	print_device_short(dev, indent);
5316 
5317 	indentprintf(("Parent:\n"));
5318 	print_device_short(dev->parent, indent+1);
5319 	indentprintf(("Driver:\n"));
5320 	print_driver_short(dev->driver, indent+1);
5321 	indentprintf(("Devclass:\n"));
5322 	print_devclass_short(dev->devclass, indent+1);
5323 }
5324 
5325 void
5326 print_device_tree_short(device_t dev, int indent)
5327 /* print the device and all its children (indented) */
5328 {
5329 	device_t child;
5330 
5331 	if (!dev)
5332 		return;
5333 
5334 	print_device_short(dev, indent);
5335 
5336 	TAILQ_FOREACH(child, &dev->children, link) {
5337 		print_device_tree_short(child, indent+1);
5338 	}
5339 }
5340 
5341 void
5342 print_device_tree(device_t dev, int indent)
5343 /* print the device and all its children (indented) */
5344 {
5345 	device_t child;
5346 
5347 	if (!dev)
5348 		return;
5349 
5350 	print_device(dev, indent);
5351 
5352 	TAILQ_FOREACH(child, &dev->children, link) {
5353 		print_device_tree(child, indent+1);
5354 	}
5355 }
5356 
5357 static void
5358 print_driver_short(driver_t *driver, int indent)
5359 {
5360 	if (!driver)
5361 		return;
5362 
5363 	indentprintf(("driver %s: softc size = %zd\n",
5364 	    driver->name, driver->size));
5365 }
5366 
5367 static void
5368 print_driver(driver_t *driver, int indent)
5369 {
5370 	if (!driver)
5371 		return;
5372 
5373 	print_driver_short(driver, indent);
5374 }
5375 
5376 static void
5377 print_driver_list(driver_list_t drivers, int indent)
5378 {
5379 	driverlink_t driver;
5380 
5381 	TAILQ_FOREACH(driver, &drivers, link) {
5382 		print_driver(driver->driver, indent);
5383 	}
5384 }
5385 
5386 static void
5387 print_devclass_short(devclass_t dc, int indent)
5388 {
5389 	if ( !dc )
5390 		return;
5391 
5392 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5393 }
5394 
5395 static void
5396 print_devclass(devclass_t dc, int indent)
5397 {
5398 	int i;
5399 
5400 	if ( !dc )
5401 		return;
5402 
5403 	print_devclass_short(dc, indent);
5404 	indentprintf(("Drivers:\n"));
5405 	print_driver_list(dc->drivers, indent+1);
5406 
5407 	indentprintf(("Devices:\n"));
5408 	for (i = 0; i < dc->maxunit; i++)
5409 		if (dc->devices[i])
5410 			print_device(dc->devices[i], indent+1);
5411 }
5412 
5413 void
5414 print_devclass_list_short(void)
5415 {
5416 	devclass_t dc;
5417 
5418 	printf("Short listing of devclasses, drivers & devices:\n");
5419 	TAILQ_FOREACH(dc, &devclasses, link) {
5420 		print_devclass_short(dc, 0);
5421 	}
5422 }
5423 
5424 void
5425 print_devclass_list(void)
5426 {
5427 	devclass_t dc;
5428 
5429 	printf("Full listing of devclasses, drivers & devices:\n");
5430 	TAILQ_FOREACH(dc, &devclasses, link) {
5431 		print_devclass(dc, 0);
5432 	}
5433 }
5434 
5435 #endif
5436 
5437 /*
5438  * User-space access to the device tree.
5439  *
5440  * We implement a small set of nodes:
5441  *
5442  * hw.bus			Single integer read method to obtain the
5443  *				current generation count.
5444  * hw.bus.devices		Reads the entire device tree in flat space.
5445  * hw.bus.rman			Resource manager interface
5446  *
5447  * We might like to add the ability to scan devclasses and/or drivers to
5448  * determine what else is currently loaded/available.
5449  */
5450 
5451 static int
5452 sysctl_bus(SYSCTL_HANDLER_ARGS)
5453 {
5454 	struct u_businfo	ubus;
5455 
5456 	ubus.ub_version = BUS_USER_VERSION;
5457 	ubus.ub_generation = bus_data_generation;
5458 
5459 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5460 }
5461 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
5462     "bus-related data");
5463 
5464 static int
5465 sysctl_devices(SYSCTL_HANDLER_ARGS)
5466 {
5467 	int			*name = (int *)arg1;
5468 	u_int			namelen = arg2;
5469 	int			index;
5470 	device_t		dev;
5471 	struct u_device		*udev;
5472 	int			error;
5473 	char			*walker, *ep;
5474 
5475 	if (namelen != 2)
5476 		return (EINVAL);
5477 
5478 	if (bus_data_generation_check(name[0]))
5479 		return (EINVAL);
5480 
5481 	index = name[1];
5482 
5483 	/*
5484 	 * Scan the list of devices, looking for the requested index.
5485 	 */
5486 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5487 		if (index-- == 0)
5488 			break;
5489 	}
5490 	if (dev == NULL)
5491 		return (ENOENT);
5492 
5493 	/*
5494 	 * Populate the return item, careful not to overflow the buffer.
5495 	 */
5496 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5497 	if (udev == NULL)
5498 		return (ENOMEM);
5499 	udev->dv_handle = (uintptr_t)dev;
5500 	udev->dv_parent = (uintptr_t)dev->parent;
5501 	udev->dv_devflags = dev->devflags;
5502 	udev->dv_flags = dev->flags;
5503 	udev->dv_state = dev->state;
5504 	walker = udev->dv_fields;
5505 	ep = walker + sizeof(udev->dv_fields);
5506 #define CP(src)						\
5507 	if ((src) == NULL)				\
5508 		*walker++ = '\0';			\
5509 	else {						\
5510 		strlcpy(walker, (src), ep - walker);	\
5511 		walker += strlen(walker) + 1;		\
5512 	}						\
5513 	if (walker >= ep)				\
5514 		break;
5515 
5516 	do {
5517 		CP(dev->nameunit);
5518 		CP(dev->desc);
5519 		CP(dev->driver != NULL ? dev->driver->name : NULL);
5520 		bus_child_pnpinfo_str(dev, walker, ep - walker);
5521 		walker += strlen(walker) + 1;
5522 		if (walker >= ep)
5523 			break;
5524 		bus_child_location_str(dev, walker, ep - walker);
5525 		walker += strlen(walker) + 1;
5526 		if (walker >= ep)
5527 			break;
5528 		*walker++ = '\0';
5529 	} while (0);
5530 #undef CP
5531 	error = SYSCTL_OUT(req, udev, sizeof(*udev));
5532 	free(udev, M_BUS);
5533 	return (error);
5534 }
5535 
5536 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
5537     "system device tree");
5538 
5539 int
5540 bus_data_generation_check(int generation)
5541 {
5542 	if (generation != bus_data_generation)
5543 		return (1);
5544 
5545 	/* XXX generate optimised lists here? */
5546 	return (0);
5547 }
5548 
5549 void
5550 bus_data_generation_update(void)
5551 {
5552 	bus_data_generation++;
5553 }
5554 
5555 int
5556 bus_free_resource(device_t dev, int type, struct resource *r)
5557 {
5558 	if (r == NULL)
5559 		return (0);
5560 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5561 }
5562 
5563 device_t
5564 device_lookup_by_name(const char *name)
5565 {
5566 	device_t dev;
5567 
5568 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5569 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5570 			return (dev);
5571 	}
5572 	return (NULL);
5573 }
5574 
5575 /*
5576  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5577  * implicit semantics on open, so it could not be reused for this.
5578  * Another option would be to call this /dev/bus?
5579  */
5580 static int
5581 find_device(struct devreq *req, device_t *devp)
5582 {
5583 	device_t dev;
5584 
5585 	/*
5586 	 * First, ensure that the name is nul terminated.
5587 	 */
5588 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5589 		return (EINVAL);
5590 
5591 	/*
5592 	 * Second, try to find an attached device whose name matches
5593 	 * 'name'.
5594 	 */
5595 	dev = device_lookup_by_name(req->dr_name);
5596 	if (dev != NULL) {
5597 		*devp = dev;
5598 		return (0);
5599 	}
5600 
5601 	/* Finally, give device enumerators a chance. */
5602 	dev = NULL;
5603 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5604 	if (dev == NULL)
5605 		return (ENOENT);
5606 	*devp = dev;
5607 	return (0);
5608 }
5609 
5610 static bool
5611 driver_exists(device_t bus, const char *driver)
5612 {
5613 	devclass_t dc;
5614 
5615 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5616 		if (devclass_find_driver_internal(dc, driver) != NULL)
5617 			return (true);
5618 	}
5619 	return (false);
5620 }
5621 
5622 static void
5623 device_gen_nomatch(device_t dev)
5624 {
5625 	device_t child;
5626 
5627 	if (dev->flags & DF_NEEDNOMATCH &&
5628 	    dev->state == DS_NOTPRESENT) {
5629 		BUS_PROBE_NOMATCH(dev->parent, dev);
5630 		devnomatch(dev);
5631 		dev->flags |= DF_DONENOMATCH;
5632 	}
5633 	dev->flags &= ~DF_NEEDNOMATCH;
5634 	TAILQ_FOREACH(child, &dev->children, link) {
5635 		device_gen_nomatch(child);
5636 	}
5637 }
5638 
5639 static void
5640 device_do_deferred_actions(void)
5641 {
5642 	devclass_t dc;
5643 	driverlink_t dl;
5644 
5645 	/*
5646 	 * Walk through the devclasses to find all the drivers we've tagged as
5647 	 * deferred during the freeze and call the driver added routines. They
5648 	 * have already been added to the lists in the background, so the driver
5649 	 * added routines that trigger a probe will have all the right bidders
5650 	 * for the probe auction.
5651 	 */
5652 	TAILQ_FOREACH(dc, &devclasses, link) {
5653 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5654 			if (dl->flags & DL_DEFERRED_PROBE) {
5655 				devclass_driver_added(dc, dl->driver);
5656 				dl->flags &= ~DL_DEFERRED_PROBE;
5657 			}
5658 		}
5659 	}
5660 
5661 	/*
5662 	 * We also defer no-match events during a freeze. Walk the tree and
5663 	 * generate all the pent-up events that are still relevant.
5664 	 */
5665 	device_gen_nomatch(root_bus);
5666 	bus_data_generation_update();
5667 }
5668 
5669 static int
5670 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5671     struct thread *td)
5672 {
5673 	struct devreq *req;
5674 	device_t dev;
5675 	int error, old;
5676 
5677 	/* Locate the device to control. */
5678 	mtx_lock(&Giant);
5679 	req = (struct devreq *)data;
5680 	switch (cmd) {
5681 	case DEV_ATTACH:
5682 	case DEV_DETACH:
5683 	case DEV_ENABLE:
5684 	case DEV_DISABLE:
5685 	case DEV_SUSPEND:
5686 	case DEV_RESUME:
5687 	case DEV_SET_DRIVER:
5688 	case DEV_CLEAR_DRIVER:
5689 	case DEV_RESCAN:
5690 	case DEV_DELETE:
5691 	case DEV_RESET:
5692 		error = priv_check(td, PRIV_DRIVER);
5693 		if (error == 0)
5694 			error = find_device(req, &dev);
5695 		break;
5696 	case DEV_FREEZE:
5697 	case DEV_THAW:
5698 		error = priv_check(td, PRIV_DRIVER);
5699 		break;
5700 	default:
5701 		error = ENOTTY;
5702 		break;
5703 	}
5704 	if (error) {
5705 		mtx_unlock(&Giant);
5706 		return (error);
5707 	}
5708 
5709 	/* Perform the requested operation. */
5710 	switch (cmd) {
5711 	case DEV_ATTACH:
5712 		if (device_is_attached(dev) && (dev->flags & DF_REBID) == 0)
5713 			error = EBUSY;
5714 		else if (!device_is_enabled(dev))
5715 			error = ENXIO;
5716 		else
5717 			error = device_probe_and_attach(dev);
5718 		break;
5719 	case DEV_DETACH:
5720 		if (!device_is_attached(dev)) {
5721 			error = ENXIO;
5722 			break;
5723 		}
5724 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5725 			error = device_quiesce(dev);
5726 			if (error)
5727 				break;
5728 		}
5729 		error = device_detach(dev);
5730 		break;
5731 	case DEV_ENABLE:
5732 		if (device_is_enabled(dev)) {
5733 			error = EBUSY;
5734 			break;
5735 		}
5736 
5737 		/*
5738 		 * If the device has been probed but not attached (e.g.
5739 		 * when it has been disabled by a loader hint), just
5740 		 * attach the device rather than doing a full probe.
5741 		 */
5742 		device_enable(dev);
5743 		if (device_is_alive(dev)) {
5744 			/*
5745 			 * If the device was disabled via a hint, clear
5746 			 * the hint.
5747 			 */
5748 			if (resource_disabled(dev->driver->name, dev->unit))
5749 				resource_unset_value(dev->driver->name,
5750 				    dev->unit, "disabled");
5751 			error = device_attach(dev);
5752 		} else
5753 			error = device_probe_and_attach(dev);
5754 		break;
5755 	case DEV_DISABLE:
5756 		if (!device_is_enabled(dev)) {
5757 			error = ENXIO;
5758 			break;
5759 		}
5760 
5761 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5762 			error = device_quiesce(dev);
5763 			if (error)
5764 				break;
5765 		}
5766 
5767 		/*
5768 		 * Force DF_FIXEDCLASS on around detach to preserve
5769 		 * the existing name.
5770 		 */
5771 		old = dev->flags;
5772 		dev->flags |= DF_FIXEDCLASS;
5773 		error = device_detach(dev);
5774 		if (!(old & DF_FIXEDCLASS))
5775 			dev->flags &= ~DF_FIXEDCLASS;
5776 		if (error == 0)
5777 			device_disable(dev);
5778 		break;
5779 	case DEV_SUSPEND:
5780 		if (device_is_suspended(dev)) {
5781 			error = EBUSY;
5782 			break;
5783 		}
5784 		if (device_get_parent(dev) == NULL) {
5785 			error = EINVAL;
5786 			break;
5787 		}
5788 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5789 		break;
5790 	case DEV_RESUME:
5791 		if (!device_is_suspended(dev)) {
5792 			error = EINVAL;
5793 			break;
5794 		}
5795 		if (device_get_parent(dev) == NULL) {
5796 			error = EINVAL;
5797 			break;
5798 		}
5799 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5800 		break;
5801 	case DEV_SET_DRIVER: {
5802 		devclass_t dc;
5803 		char driver[128];
5804 
5805 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5806 		if (error)
5807 			break;
5808 		if (driver[0] == '\0') {
5809 			error = EINVAL;
5810 			break;
5811 		}
5812 		if (dev->devclass != NULL &&
5813 		    strcmp(driver, dev->devclass->name) == 0)
5814 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5815 			break;
5816 
5817 		/*
5818 		 * Scan drivers for this device's bus looking for at
5819 		 * least one matching driver.
5820 		 */
5821 		if (dev->parent == NULL) {
5822 			error = EINVAL;
5823 			break;
5824 		}
5825 		if (!driver_exists(dev->parent, driver)) {
5826 			error = ENOENT;
5827 			break;
5828 		}
5829 		dc = devclass_create(driver);
5830 		if (dc == NULL) {
5831 			error = ENOMEM;
5832 			break;
5833 		}
5834 
5835 		/* Detach device if necessary. */
5836 		if (device_is_attached(dev)) {
5837 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5838 				error = device_detach(dev);
5839 			else
5840 				error = EBUSY;
5841 			if (error)
5842 				break;
5843 		}
5844 
5845 		/* Clear any previously-fixed device class and unit. */
5846 		if (dev->flags & DF_FIXEDCLASS)
5847 			devclass_delete_device(dev->devclass, dev);
5848 		dev->flags |= DF_WILDCARD;
5849 		dev->unit = -1;
5850 
5851 		/* Force the new device class. */
5852 		error = devclass_add_device(dc, dev);
5853 		if (error)
5854 			break;
5855 		dev->flags |= DF_FIXEDCLASS;
5856 		error = device_probe_and_attach(dev);
5857 		break;
5858 	}
5859 	case DEV_CLEAR_DRIVER:
5860 		if (!(dev->flags & DF_FIXEDCLASS)) {
5861 			error = 0;
5862 			break;
5863 		}
5864 		if (device_is_attached(dev)) {
5865 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5866 				error = device_detach(dev);
5867 			else
5868 				error = EBUSY;
5869 			if (error)
5870 				break;
5871 		}
5872 
5873 		dev->flags &= ~DF_FIXEDCLASS;
5874 		dev->flags |= DF_WILDCARD;
5875 		devclass_delete_device(dev->devclass, dev);
5876 		error = device_probe_and_attach(dev);
5877 		break;
5878 	case DEV_RESCAN:
5879 		if (!device_is_attached(dev)) {
5880 			error = ENXIO;
5881 			break;
5882 		}
5883 		error = BUS_RESCAN(dev);
5884 		break;
5885 	case DEV_DELETE: {
5886 		device_t parent;
5887 
5888 		parent = device_get_parent(dev);
5889 		if (parent == NULL) {
5890 			error = EINVAL;
5891 			break;
5892 		}
5893 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5894 			if (bus_child_present(dev) != 0) {
5895 				error = EBUSY;
5896 				break;
5897 			}
5898 		}
5899 
5900 		error = device_delete_child(parent, dev);
5901 		break;
5902 	}
5903 	case DEV_FREEZE:
5904 		if (device_frozen)
5905 			error = EBUSY;
5906 		else
5907 			device_frozen = true;
5908 		break;
5909 	case DEV_THAW:
5910 		if (!device_frozen)
5911 			error = EBUSY;
5912 		else {
5913 			device_do_deferred_actions();
5914 			device_frozen = false;
5915 		}
5916 		break;
5917 	case DEV_RESET:
5918 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5919 			error = EINVAL;
5920 			break;
5921 		}
5922 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5923 		    req->dr_flags);
5924 		break;
5925 	}
5926 	mtx_unlock(&Giant);
5927 	return (error);
5928 }
5929 
5930 static struct cdevsw devctl2_cdevsw = {
5931 	.d_version =	D_VERSION,
5932 	.d_ioctl =	devctl2_ioctl,
5933 	.d_name =	"devctl2",
5934 };
5935 
5936 static void
5937 devctl2_init(void)
5938 {
5939 
5940 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5941 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5942 }
5943 
5944 /*
5945  * APIs to manage deprecation and obsolescence.
5946  */
5947 static int obsolete_panic = 0;
5948 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
5949     "Panic when obsolete features are used (0 = never, 1 = if osbolete, "
5950     "2 = if deprecated)");
5951 
5952 static void
5953 gone_panic(int major, int running, const char *msg)
5954 {
5955 
5956 	switch (obsolete_panic)
5957 	{
5958 	case 0:
5959 		return;
5960 	case 1:
5961 		if (running < major)
5962 			return;
5963 		/* FALLTHROUGH */
5964 	default:
5965 		panic("%s", msg);
5966 	}
5967 }
5968 
5969 void
5970 _gone_in(int major, const char *msg)
5971 {
5972 
5973 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5974 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5975 		printf("Obsolete code will be removed soon: %s\n", msg);
5976 	else
5977 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
5978 		    major, msg);
5979 }
5980 
5981 void
5982 _gone_in_dev(device_t dev, int major, const char *msg)
5983 {
5984 
5985 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
5986 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
5987 		device_printf(dev,
5988 		    "Obsolete code will be removed soon: %s\n", msg);
5989 	else
5990 		device_printf(dev,
5991 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
5992 		    major, msg);
5993 }
5994 
5995 #ifdef DDB
5996 DB_SHOW_COMMAND(device, db_show_device)
5997 {
5998 	device_t dev;
5999 
6000 	if (!have_addr)
6001 		return;
6002 
6003 	dev = (device_t)addr;
6004 
6005 	db_printf("name:    %s\n", device_get_nameunit(dev));
6006 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6007 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6008 	db_printf("  addr:    %p\n", dev);
6009 	db_printf("  parent:  %p\n", dev->parent);
6010 	db_printf("  softc:   %p\n", dev->softc);
6011 	db_printf("  ivars:   %p\n", dev->ivars);
6012 }
6013 
6014 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6015 {
6016 	device_t dev;
6017 
6018 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6019 		db_show_device((db_expr_t)dev, true, count, modif);
6020 	}
6021 }
6022 #endif
6023