xref: /freebsd/sys/kern/subr_bus.c (revision f499134dd403eeeba8283e2640e2654c8da62430)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/refcount.h>
55 #include <sys/rman.h>
56 #include <sys/sbuf.h>
57 #include <sys/selinfo.h>
58 #include <sys/signalvar.h>
59 #include <sys/smp.h>
60 #include <sys/sysctl.h>
61 #include <sys/systm.h>
62 #include <sys/uio.h>
63 #include <sys/bus.h>
64 #include <sys/cpuset.h>
65 
66 #include <net/vnet.h>
67 
68 #include <machine/cpu.h>
69 #include <machine/stdarg.h>
70 
71 #include <vm/uma.h>
72 #include <vm/vm.h>
73 
74 #include <ddb/ddb.h>
75 
76 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
77     NULL);
78 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
79     NULL);
80 
81 /*
82  * Used to attach drivers to devclasses.
83  */
84 typedef struct driverlink *driverlink_t;
85 struct driverlink {
86 	kobj_class_t	driver;
87 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
88 	int		pass;
89 	int		flags;
90 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
91 	TAILQ_ENTRY(driverlink) passlink;
92 };
93 
94 /*
95  * Forward declarations
96  */
97 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
98 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
99 typedef TAILQ_HEAD(device_list, _device) device_list_t;
100 
101 struct devclass {
102 	TAILQ_ENTRY(devclass) link;
103 	devclass_t	parent;		/* parent in devclass hierarchy */
104 	driver_list_t	drivers;	/* bus devclasses store drivers for bus */
105 	char		*name;
106 	device_t	*devices;	/* array of devices indexed by unit */
107 	int		maxunit;	/* size of devices array */
108 	int		flags;
109 #define DC_HAS_CHILDREN		1
110 
111 	struct sysctl_ctx_list sysctl_ctx;
112 	struct sysctl_oid *sysctl_tree;
113 };
114 
115 /**
116  * @brief Implementation of _device.
117  *
118  * The structure is named "_device" instead of "device" to avoid type confusion
119  * caused by other subsystems defining a (struct device).
120  */
121 struct _device {
122 	/*
123 	 * A device is a kernel object. The first field must be the
124 	 * current ops table for the object.
125 	 */
126 	KOBJ_FIELDS;
127 
128 	/*
129 	 * Device hierarchy.
130 	 */
131 	TAILQ_ENTRY(_device)	link;	/**< list of devices in parent */
132 	TAILQ_ENTRY(_device)	devlink; /**< global device list membership */
133 	device_t	parent;		/**< parent of this device  */
134 	device_list_t	children;	/**< list of child devices */
135 
136 	/*
137 	 * Details of this device.
138 	 */
139 	driver_t	*driver;	/**< current driver */
140 	devclass_t	devclass;	/**< current device class */
141 	int		unit;		/**< current unit number */
142 	char*		nameunit;	/**< name+unit e.g. foodev0 */
143 	char*		desc;		/**< driver specific description */
144 	u_int		busy;		/**< count of calls to device_busy() */
145 	device_state_t	state;		/**< current device state  */
146 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
147 	u_int		flags;		/**< internal device flags  */
148 	u_int	order;			/**< order from device_add_child_ordered() */
149 	void	*ivars;			/**< instance variables  */
150 	void	*softc;			/**< current driver's variables  */
151 
152 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
153 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
154 };
155 
156 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
157 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
158 
159 EVENTHANDLER_LIST_DEFINE(device_attach);
160 EVENTHANDLER_LIST_DEFINE(device_detach);
161 EVENTHANDLER_LIST_DEFINE(dev_lookup);
162 
163 static void devctl2_init(void);
164 static bool device_frozen;
165 
166 #define DRIVERNAME(d)	((d)? d->name : "no driver")
167 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
168 
169 #ifdef BUS_DEBUG
170 
171 static int bus_debug = 1;
172 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
173     "Bus debug level");
174 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
175 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
176 
177 /**
178  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
179  * prevent syslog from deleting initial spaces
180  */
181 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
182 
183 static void print_device_short(device_t dev, int indent);
184 static void print_device(device_t dev, int indent);
185 void print_device_tree_short(device_t dev, int indent);
186 void print_device_tree(device_t dev, int indent);
187 static void print_driver_short(driver_t *driver, int indent);
188 static void print_driver(driver_t *driver, int indent);
189 static void print_driver_list(driver_list_t drivers, int indent);
190 static void print_devclass_short(devclass_t dc, int indent);
191 static void print_devclass(devclass_t dc, int indent);
192 void print_devclass_list_short(void);
193 void print_devclass_list(void);
194 
195 #else
196 /* Make the compiler ignore the function calls */
197 #define PDEBUG(a)			/* nop */
198 #define DEVICENAME(d)			/* nop */
199 
200 #define print_device_short(d,i)		/* nop */
201 #define print_device(d,i)		/* nop */
202 #define print_device_tree_short(d,i)	/* nop */
203 #define print_device_tree(d,i)		/* nop */
204 #define print_driver_short(d,i)		/* nop */
205 #define print_driver(d,i)		/* nop */
206 #define print_driver_list(d,i)		/* nop */
207 #define print_devclass_short(d,i)	/* nop */
208 #define print_devclass(d,i)		/* nop */
209 #define print_devclass_list_short()	/* nop */
210 #define print_devclass_list()		/* nop */
211 #endif
212 
213 /*
214  * dev sysctl tree
215  */
216 
217 enum {
218 	DEVCLASS_SYSCTL_PARENT,
219 };
220 
221 static int
222 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
223 {
224 	devclass_t dc = (devclass_t)arg1;
225 	const char *value;
226 
227 	switch (arg2) {
228 	case DEVCLASS_SYSCTL_PARENT:
229 		value = dc->parent ? dc->parent->name : "";
230 		break;
231 	default:
232 		return (EINVAL);
233 	}
234 	return (SYSCTL_OUT_STR(req, value));
235 }
236 
237 static void
238 devclass_sysctl_init(devclass_t dc)
239 {
240 	if (dc->sysctl_tree != NULL)
241 		return;
242 	sysctl_ctx_init(&dc->sysctl_ctx);
243 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
244 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
245 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
246 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
247 	    OID_AUTO, "%parent",
248 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
249 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
250 	    "parent class");
251 }
252 
253 enum {
254 	DEVICE_SYSCTL_DESC,
255 	DEVICE_SYSCTL_DRIVER,
256 	DEVICE_SYSCTL_LOCATION,
257 	DEVICE_SYSCTL_PNPINFO,
258 	DEVICE_SYSCTL_PARENT,
259 };
260 
261 static int
262 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
263 {
264 	struct sbuf sb;
265 	device_t dev = (device_t)arg1;
266 	int error;
267 
268 	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
269 	sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
270 	switch (arg2) {
271 	case DEVICE_SYSCTL_DESC:
272 		sbuf_cat(&sb, dev->desc ? dev->desc : "");
273 		break;
274 	case DEVICE_SYSCTL_DRIVER:
275 		sbuf_cat(&sb, dev->driver ? dev->driver->name : "");
276 		break;
277 	case DEVICE_SYSCTL_LOCATION:
278 		bus_child_location(dev, &sb);
279 		break;
280 	case DEVICE_SYSCTL_PNPINFO:
281 		bus_child_pnpinfo(dev, &sb);
282 		break;
283 	case DEVICE_SYSCTL_PARENT:
284 		sbuf_cat(&sb, dev->parent ? dev->parent->nameunit : "");
285 		break;
286 	default:
287 		sbuf_delete(&sb);
288 		return (EINVAL);
289 	}
290 	error = sbuf_finish(&sb);
291 	sbuf_delete(&sb);
292 	return (error);
293 }
294 
295 static void
296 device_sysctl_init(device_t dev)
297 {
298 	devclass_t dc = dev->devclass;
299 	int domain;
300 
301 	if (dev->sysctl_tree != NULL)
302 		return;
303 	devclass_sysctl_init(dc);
304 	sysctl_ctx_init(&dev->sysctl_ctx);
305 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
306 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
307 	    dev->nameunit + strlen(dc->name),
308 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
309 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
310 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
311 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
312 	    "device description");
313 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
314 	    OID_AUTO, "%driver",
315 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
316 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
317 	    "device driver name");
318 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
319 	    OID_AUTO, "%location",
320 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
321 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
322 	    "device location relative to parent");
323 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
324 	    OID_AUTO, "%pnpinfo",
325 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
326 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
327 	    "device identification");
328 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
329 	    OID_AUTO, "%parent",
330 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
331 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
332 	    "parent device");
333 	if (bus_get_domain(dev, &domain) == 0)
334 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
335 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
336 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
337 }
338 
339 static void
340 device_sysctl_update(device_t dev)
341 {
342 	devclass_t dc = dev->devclass;
343 
344 	if (dev->sysctl_tree == NULL)
345 		return;
346 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
347 }
348 
349 static void
350 device_sysctl_fini(device_t dev)
351 {
352 	if (dev->sysctl_tree == NULL)
353 		return;
354 	sysctl_ctx_free(&dev->sysctl_ctx);
355 	dev->sysctl_tree = NULL;
356 }
357 
358 /*
359  * /dev/devctl implementation
360  */
361 
362 /*
363  * This design allows only one reader for /dev/devctl.  This is not desirable
364  * in the long run, but will get a lot of hair out of this implementation.
365  * Maybe we should make this device a clonable device.
366  *
367  * Also note: we specifically do not attach a device to the device_t tree
368  * to avoid potential chicken and egg problems.  One could argue that all
369  * of this belongs to the root node.
370  */
371 
372 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
373 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
374 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
375 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
376     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
377 
378 static d_open_t		devopen;
379 static d_close_t	devclose;
380 static d_read_t		devread;
381 static d_ioctl_t	devioctl;
382 static d_poll_t		devpoll;
383 static d_kqfilter_t	devkqfilter;
384 
385 static struct cdevsw dev_cdevsw = {
386 	.d_version =	D_VERSION,
387 	.d_open =	devopen,
388 	.d_close =	devclose,
389 	.d_read =	devread,
390 	.d_ioctl =	devioctl,
391 	.d_poll =	devpoll,
392 	.d_kqfilter =	devkqfilter,
393 	.d_name =	"devctl",
394 };
395 
396 #define DEVCTL_BUFFER (1024 - sizeof(void *))
397 struct dev_event_info {
398 	STAILQ_ENTRY(dev_event_info) dei_link;
399 	char dei_data[DEVCTL_BUFFER];
400 };
401 
402 STAILQ_HEAD(devq, dev_event_info);
403 
404 static struct dev_softc {
405 	int		inuse;
406 	int		nonblock;
407 	int		queued;
408 	int		async;
409 	struct mtx	mtx;
410 	struct cv	cv;
411 	struct selinfo	sel;
412 	struct devq	devq;
413 	struct sigio	*sigio;
414 	uma_zone_t	zone;
415 } devsoftc;
416 
417 static void	filt_devctl_detach(struct knote *kn);
418 static int	filt_devctl_read(struct knote *kn, long hint);
419 
420 struct filterops devctl_rfiltops = {
421 	.f_isfd = 1,
422 	.f_detach = filt_devctl_detach,
423 	.f_event = filt_devctl_read,
424 };
425 
426 static struct cdev *devctl_dev;
427 
428 static void
429 devinit(void)
430 {
431 	int reserve;
432 	uma_zone_t z;
433 
434 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
435 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
436 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
437 	cv_init(&devsoftc.cv, "dev cv");
438 	STAILQ_INIT(&devsoftc.devq);
439 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
440 	if (devctl_queue_length > 0) {
441 		/*
442 		 * Allocate a zone for the messages. Preallocate 2% of these for
443 		 * a reserve. Allow only devctl_queue_length slabs to cap memory
444 		 * usage.  The reserve usually allows coverage of surges of
445 		 * events during memory shortages. Normally we won't have to
446 		 * re-use events from the queue, but will in extreme shortages.
447 		 */
448 		z = devsoftc.zone = uma_zcreate("DEVCTL",
449 		    sizeof(struct dev_event_info), NULL, NULL, NULL, NULL,
450 		    UMA_ALIGN_PTR, 0);
451 		reserve = max(devctl_queue_length / 50, 100);	/* 2% reserve */
452 		uma_zone_set_max(z, devctl_queue_length);
453 		uma_zone_set_maxcache(z, 0);
454 		uma_zone_reserve(z, reserve);
455 		uma_prealloc(z, reserve);
456 	}
457 	devctl2_init();
458 }
459 
460 static int
461 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
462 {
463 	mtx_lock(&devsoftc.mtx);
464 	if (devsoftc.inuse) {
465 		mtx_unlock(&devsoftc.mtx);
466 		return (EBUSY);
467 	}
468 	/* move to init */
469 	devsoftc.inuse = 1;
470 	mtx_unlock(&devsoftc.mtx);
471 	return (0);
472 }
473 
474 static int
475 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
476 {
477 	mtx_lock(&devsoftc.mtx);
478 	devsoftc.inuse = 0;
479 	devsoftc.nonblock = 0;
480 	devsoftc.async = 0;
481 	cv_broadcast(&devsoftc.cv);
482 	funsetown(&devsoftc.sigio);
483 	mtx_unlock(&devsoftc.mtx);
484 	return (0);
485 }
486 
487 /*
488  * The read channel for this device is used to report changes to
489  * userland in realtime.  We are required to free the data as well as
490  * the n1 object because we allocate them separately.  Also note that
491  * we return one record at a time.  If you try to read this device a
492  * character at a time, you will lose the rest of the data.  Listening
493  * programs are expected to cope.
494  */
495 static int
496 devread(struct cdev *dev, struct uio *uio, int ioflag)
497 {
498 	struct dev_event_info *n1;
499 	int rv;
500 
501 	mtx_lock(&devsoftc.mtx);
502 	while (STAILQ_EMPTY(&devsoftc.devq)) {
503 		if (devsoftc.nonblock) {
504 			mtx_unlock(&devsoftc.mtx);
505 			return (EAGAIN);
506 		}
507 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
508 		if (rv) {
509 			/*
510 			 * Need to translate ERESTART to EINTR here? -- jake
511 			 */
512 			mtx_unlock(&devsoftc.mtx);
513 			return (rv);
514 		}
515 	}
516 	n1 = STAILQ_FIRST(&devsoftc.devq);
517 	STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
518 	devsoftc.queued--;
519 	mtx_unlock(&devsoftc.mtx);
520 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
521 	uma_zfree(devsoftc.zone, n1);
522 	return (rv);
523 }
524 
525 static	int
526 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
527 {
528 	switch (cmd) {
529 	case FIONBIO:
530 		if (*(int*)data)
531 			devsoftc.nonblock = 1;
532 		else
533 			devsoftc.nonblock = 0;
534 		return (0);
535 	case FIOASYNC:
536 		if (*(int*)data)
537 			devsoftc.async = 1;
538 		else
539 			devsoftc.async = 0;
540 		return (0);
541 	case FIOSETOWN:
542 		return fsetown(*(int *)data, &devsoftc.sigio);
543 	case FIOGETOWN:
544 		*(int *)data = fgetown(&devsoftc.sigio);
545 		return (0);
546 
547 		/* (un)Support for other fcntl() calls. */
548 	case FIOCLEX:
549 	case FIONCLEX:
550 	case FIONREAD:
551 	default:
552 		break;
553 	}
554 	return (ENOTTY);
555 }
556 
557 static	int
558 devpoll(struct cdev *dev, int events, struct thread *td)
559 {
560 	int	revents = 0;
561 
562 	mtx_lock(&devsoftc.mtx);
563 	if (events & (POLLIN | POLLRDNORM)) {
564 		if (!STAILQ_EMPTY(&devsoftc.devq))
565 			revents = events & (POLLIN | POLLRDNORM);
566 		else
567 			selrecord(td, &devsoftc.sel);
568 	}
569 	mtx_unlock(&devsoftc.mtx);
570 
571 	return (revents);
572 }
573 
574 static int
575 devkqfilter(struct cdev *dev, struct knote *kn)
576 {
577 	int error;
578 
579 	if (kn->kn_filter == EVFILT_READ) {
580 		kn->kn_fop = &devctl_rfiltops;
581 		knlist_add(&devsoftc.sel.si_note, kn, 0);
582 		error = 0;
583 	} else
584 		error = EINVAL;
585 	return (error);
586 }
587 
588 static void
589 filt_devctl_detach(struct knote *kn)
590 {
591 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
592 }
593 
594 static int
595 filt_devctl_read(struct knote *kn, long hint)
596 {
597 	kn->kn_data = devsoftc.queued;
598 	return (kn->kn_data != 0);
599 }
600 
601 /**
602  * @brief Return whether the userland process is running
603  */
604 bool
605 devctl_process_running(void)
606 {
607 	return (devsoftc.inuse == 1);
608 }
609 
610 static struct dev_event_info *
611 devctl_alloc_dei(void)
612 {
613 	struct dev_event_info *dei = NULL;
614 
615 	mtx_lock(&devsoftc.mtx);
616 	if (devctl_queue_length == 0)
617 		goto out;
618 	dei = uma_zalloc(devsoftc.zone, M_NOWAIT);
619 	if (dei == NULL)
620 		dei = uma_zalloc(devsoftc.zone, M_NOWAIT | M_USE_RESERVE);
621 	if (dei == NULL) {
622 		/*
623 		 * Guard against no items in the queue. Normally, this won't
624 		 * happen, but if lots of events happen all at once and there's
625 		 * a chance we're out of allocated space but none have yet been
626 		 * queued when we get here, leaving nothing to steal. This can
627 		 * also happen with error injection. Fail safe by returning
628 		 * NULL in that case..
629 		 */
630 		if (devsoftc.queued == 0)
631 			goto out;
632 		dei = STAILQ_FIRST(&devsoftc.devq);
633 		STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
634 		devsoftc.queued--;
635 	}
636 	MPASS(dei != NULL);
637 	*dei->dei_data = '\0';
638 out:
639 	mtx_unlock(&devsoftc.mtx);
640 	return (dei);
641 }
642 
643 static struct dev_event_info *
644 devctl_alloc_dei_sb(struct sbuf *sb)
645 {
646 	struct dev_event_info *dei;
647 
648 	dei = devctl_alloc_dei();
649 	if (dei != NULL)
650 		sbuf_new(sb, dei->dei_data, sizeof(dei->dei_data), SBUF_FIXEDLEN);
651 	return (dei);
652 }
653 
654 static void
655 devctl_free_dei(struct dev_event_info *dei)
656 {
657 	uma_zfree(devsoftc.zone, dei);
658 }
659 
660 static void
661 devctl_queue(struct dev_event_info *dei)
662 {
663 	mtx_lock(&devsoftc.mtx);
664 	STAILQ_INSERT_TAIL(&devsoftc.devq, dei, dei_link);
665 	devsoftc.queued++;
666 	cv_broadcast(&devsoftc.cv);
667 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
668 	mtx_unlock(&devsoftc.mtx);
669 	selwakeup(&devsoftc.sel);
670 	if (devsoftc.async && devsoftc.sigio != NULL)
671 		pgsigio(&devsoftc.sigio, SIGIO, 0);
672 }
673 
674 /**
675  * @brief Send a 'notification' to userland, using standard ways
676  */
677 void
678 devctl_notify(const char *system, const char *subsystem, const char *type,
679     const char *data)
680 {
681 	struct dev_event_info *dei;
682 	struct sbuf sb;
683 
684 	if (system == NULL || subsystem == NULL || type == NULL)
685 		return;
686 	dei = devctl_alloc_dei_sb(&sb);
687 	if (dei == NULL)
688 		return;
689 	sbuf_cpy(&sb, "!system=");
690 	sbuf_cat(&sb, system);
691 	sbuf_cat(&sb, " subsystem=");
692 	sbuf_cat(&sb, subsystem);
693 	sbuf_cat(&sb, " type=");
694 	sbuf_cat(&sb, type);
695 	if (data != NULL) {
696 		sbuf_putc(&sb, ' ');
697 		sbuf_cat(&sb, data);
698 	}
699 	sbuf_putc(&sb, '\n');
700 	if (sbuf_finish(&sb) != 0)
701 		devctl_free_dei(dei);	/* overflow -> drop it */
702 	else
703 		devctl_queue(dei);
704 }
705 
706 /*
707  * Common routine that tries to make sending messages as easy as possible.
708  * We allocate memory for the data, copy strings into that, but do not
709  * free it unless there's an error.  The dequeue part of the driver should
710  * free the data.  We don't send data when the device is disabled.  We do
711  * send data, even when we have no listeners, because we wish to avoid
712  * races relating to startup and restart of listening applications.
713  *
714  * devaddq is designed to string together the type of event, with the
715  * object of that event, plus the plug and play info and location info
716  * for that event.  This is likely most useful for devices, but less
717  * useful for other consumers of this interface.  Those should use
718  * the devctl_notify() interface instead.
719  *
720  * Output:
721  *	${type}${what} at $(location dev) $(pnp-info dev) on $(parent dev)
722  */
723 static void
724 devaddq(const char *type, const char *what, device_t dev)
725 {
726 	struct dev_event_info *dei;
727 	const char *parstr;
728 	struct sbuf sb;
729 
730 	dei = devctl_alloc_dei_sb(&sb);
731 	if (dei == NULL)
732 		return;
733 	sbuf_cpy(&sb, type);
734 	sbuf_cat(&sb, what);
735 	sbuf_cat(&sb, " at ");
736 
737 	/* Add in the location */
738 	bus_child_location(dev, &sb);
739 	sbuf_putc(&sb, ' ');
740 
741 	/* Add in pnpinfo */
742 	bus_child_pnpinfo(dev, &sb);
743 
744 	/* Get the parent of this device, or / if high enough in the tree. */
745 	if (device_get_parent(dev) == NULL)
746 		parstr = ".";	/* Or '/' ? */
747 	else
748 		parstr = device_get_nameunit(device_get_parent(dev));
749 	sbuf_cat(&sb, " on ");
750 	sbuf_cat(&sb, parstr);
751 	sbuf_putc(&sb, '\n');
752 	if (sbuf_finish(&sb) != 0)
753 		goto bad;
754 	devctl_queue(dei);
755 	return;
756 bad:
757 	devctl_free_dei(dei);
758 }
759 
760 /*
761  * A device was added to the tree.  We are called just after it successfully
762  * attaches (that is, probe and attach success for this device).  No call
763  * is made if a device is merely parented into the tree.  See devnomatch
764  * if probe fails.  If attach fails, no notification is sent (but maybe
765  * we should have a different message for this).
766  */
767 static void
768 devadded(device_t dev)
769 {
770 	devaddq("+", device_get_nameunit(dev), dev);
771 }
772 
773 /*
774  * A device was removed from the tree.  We are called just before this
775  * happens.
776  */
777 static void
778 devremoved(device_t dev)
779 {
780 	devaddq("-", device_get_nameunit(dev), dev);
781 }
782 
783 /*
784  * Called when there's no match for this device.  This is only called
785  * the first time that no match happens, so we don't keep getting this
786  * message.  Should that prove to be undesirable, we can change it.
787  * This is called when all drivers that can attach to a given bus
788  * decline to accept this device.  Other errors may not be detected.
789  */
790 static void
791 devnomatch(device_t dev)
792 {
793 	devaddq("?", "", dev);
794 }
795 
796 static int
797 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
798 {
799 	int q, error;
800 
801 	q = devctl_queue_length;
802 	error = sysctl_handle_int(oidp, &q, 0, req);
803 	if (error || !req->newptr)
804 		return (error);
805 	if (q < 0)
806 		return (EINVAL);
807 
808 	/*
809 	 * When set as a tunable, we've not yet initialized the mutex.
810 	 * It is safe to just assign to devctl_queue_length and return
811 	 * as we're racing no one. We'll use whatever value set in
812 	 * devinit.
813 	 */
814 	if (!mtx_initialized(&devsoftc.mtx)) {
815 		devctl_queue_length = q;
816 		return (0);
817 	}
818 
819 	/*
820 	 * XXX It's hard to grow or shrink the UMA zone. Only allow
821 	 * disabling the queue size for the moment until underlying
822 	 * UMA issues can be sorted out.
823 	 */
824 	if (q != 0)
825 		return (EINVAL);
826 	if (q == devctl_queue_length)
827 		return (0);
828 	mtx_lock(&devsoftc.mtx);
829 	devctl_queue_length = 0;
830 	uma_zdestroy(devsoftc.zone);
831 	devsoftc.zone = 0;
832 	mtx_unlock(&devsoftc.mtx);
833 	return (0);
834 }
835 
836 /**
837  * @brief safely quotes strings that might have double quotes in them.
838  *
839  * The devctl protocol relies on quoted strings having matching quotes.
840  * This routine quotes any internal quotes so the resulting string
841  * is safe to pass to snprintf to construct, for example pnp info strings.
842  *
843  * @param sb	sbuf to place the characters into
844  * @param src	Original buffer.
845  */
846 void
847 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
848 {
849 	while (*src != '\0') {
850 		if (*src == '"' || *src == '\\')
851 			sbuf_putc(sb, '\\');
852 		sbuf_putc(sb, *src++);
853 	}
854 }
855 
856 /* End of /dev/devctl code */
857 
858 static struct device_list bus_data_devices;
859 static int bus_data_generation = 1;
860 
861 static kobj_method_t null_methods[] = {
862 	KOBJMETHOD_END
863 };
864 
865 DEFINE_CLASS(null, null_methods, 0);
866 
867 /*
868  * Bus pass implementation
869  */
870 
871 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
872 int bus_current_pass = BUS_PASS_ROOT;
873 
874 /**
875  * @internal
876  * @brief Register the pass level of a new driver attachment
877  *
878  * Register a new driver attachment's pass level.  If no driver
879  * attachment with the same pass level has been added, then @p new
880  * will be added to the global passes list.
881  *
882  * @param new		the new driver attachment
883  */
884 static void
885 driver_register_pass(struct driverlink *new)
886 {
887 	struct driverlink *dl;
888 
889 	/* We only consider pass numbers during boot. */
890 	if (bus_current_pass == BUS_PASS_DEFAULT)
891 		return;
892 
893 	/*
894 	 * Walk the passes list.  If we already know about this pass
895 	 * then there is nothing to do.  If we don't, then insert this
896 	 * driver link into the list.
897 	 */
898 	TAILQ_FOREACH(dl, &passes, passlink) {
899 		if (dl->pass < new->pass)
900 			continue;
901 		if (dl->pass == new->pass)
902 			return;
903 		TAILQ_INSERT_BEFORE(dl, new, passlink);
904 		return;
905 	}
906 	TAILQ_INSERT_TAIL(&passes, new, passlink);
907 }
908 
909 /**
910  * @brief Raise the current bus pass
911  *
912  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
913  * method on the root bus to kick off a new device tree scan for each
914  * new pass level that has at least one driver.
915  */
916 void
917 bus_set_pass(int pass)
918 {
919 	struct driverlink *dl;
920 
921 	if (bus_current_pass > pass)
922 		panic("Attempt to lower bus pass level");
923 
924 	TAILQ_FOREACH(dl, &passes, passlink) {
925 		/* Skip pass values below the current pass level. */
926 		if (dl->pass <= bus_current_pass)
927 			continue;
928 
929 		/*
930 		 * Bail once we hit a driver with a pass level that is
931 		 * too high.
932 		 */
933 		if (dl->pass > pass)
934 			break;
935 
936 		/*
937 		 * Raise the pass level to the next level and rescan
938 		 * the tree.
939 		 */
940 		bus_current_pass = dl->pass;
941 		BUS_NEW_PASS(root_bus);
942 	}
943 
944 	/*
945 	 * If there isn't a driver registered for the requested pass,
946 	 * then bus_current_pass might still be less than 'pass'.  Set
947 	 * it to 'pass' in that case.
948 	 */
949 	if (bus_current_pass < pass)
950 		bus_current_pass = pass;
951 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
952 }
953 
954 /*
955  * Devclass implementation
956  */
957 
958 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
959 
960 /**
961  * @internal
962  * @brief Find or create a device class
963  *
964  * If a device class with the name @p classname exists, return it,
965  * otherwise if @p create is non-zero create and return a new device
966  * class.
967  *
968  * If @p parentname is non-NULL, the parent of the devclass is set to
969  * the devclass of that name.
970  *
971  * @param classname	the devclass name to find or create
972  * @param parentname	the parent devclass name or @c NULL
973  * @param create	non-zero to create a devclass
974  */
975 static devclass_t
976 devclass_find_internal(const char *classname, const char *parentname,
977 		       int create)
978 {
979 	devclass_t dc;
980 
981 	PDEBUG(("looking for %s", classname));
982 	if (!classname)
983 		return (NULL);
984 
985 	TAILQ_FOREACH(dc, &devclasses, link) {
986 		if (!strcmp(dc->name, classname))
987 			break;
988 	}
989 
990 	if (create && !dc) {
991 		PDEBUG(("creating %s", classname));
992 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
993 		    M_BUS, M_NOWAIT | M_ZERO);
994 		if (!dc)
995 			return (NULL);
996 		dc->parent = NULL;
997 		dc->name = (char*) (dc + 1);
998 		strcpy(dc->name, classname);
999 		TAILQ_INIT(&dc->drivers);
1000 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1001 
1002 		bus_data_generation_update();
1003 	}
1004 
1005 	/*
1006 	 * If a parent class is specified, then set that as our parent so
1007 	 * that this devclass will support drivers for the parent class as
1008 	 * well.  If the parent class has the same name don't do this though
1009 	 * as it creates a cycle that can trigger an infinite loop in
1010 	 * device_probe_child() if a device exists for which there is no
1011 	 * suitable driver.
1012 	 */
1013 	if (parentname && dc && !dc->parent &&
1014 	    strcmp(classname, parentname) != 0) {
1015 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1016 		dc->parent->flags |= DC_HAS_CHILDREN;
1017 	}
1018 
1019 	return (dc);
1020 }
1021 
1022 /**
1023  * @brief Create a device class
1024  *
1025  * If a device class with the name @p classname exists, return it,
1026  * otherwise create and return a new device class.
1027  *
1028  * @param classname	the devclass name to find or create
1029  */
1030 devclass_t
1031 devclass_create(const char *classname)
1032 {
1033 	return (devclass_find_internal(classname, NULL, TRUE));
1034 }
1035 
1036 /**
1037  * @brief Find a device class
1038  *
1039  * If a device class with the name @p classname exists, return it,
1040  * otherwise return @c NULL.
1041  *
1042  * @param classname	the devclass name to find
1043  */
1044 devclass_t
1045 devclass_find(const char *classname)
1046 {
1047 	return (devclass_find_internal(classname, NULL, FALSE));
1048 }
1049 
1050 /**
1051  * @brief Register that a device driver has been added to a devclass
1052  *
1053  * Register that a device driver has been added to a devclass.  This
1054  * is called by devclass_add_driver to accomplish the recursive
1055  * notification of all the children classes of dc, as well as dc.
1056  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1057  * the devclass.
1058  *
1059  * We do a full search here of the devclass list at each iteration
1060  * level to save storing children-lists in the devclass structure.  If
1061  * we ever move beyond a few dozen devices doing this, we may need to
1062  * reevaluate...
1063  *
1064  * @param dc		the devclass to edit
1065  * @param driver	the driver that was just added
1066  */
1067 static void
1068 devclass_driver_added(devclass_t dc, driver_t *driver)
1069 {
1070 	devclass_t parent;
1071 	int i;
1072 
1073 	/*
1074 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1075 	 */
1076 	for (i = 0; i < dc->maxunit; i++)
1077 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1078 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1079 
1080 	/*
1081 	 * Walk through the children classes.  Since we only keep a
1082 	 * single parent pointer around, we walk the entire list of
1083 	 * devclasses looking for children.  We set the
1084 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1085 	 * the parent, so we only walk the list for those devclasses
1086 	 * that have children.
1087 	 */
1088 	if (!(dc->flags & DC_HAS_CHILDREN))
1089 		return;
1090 	parent = dc;
1091 	TAILQ_FOREACH(dc, &devclasses, link) {
1092 		if (dc->parent == parent)
1093 			devclass_driver_added(dc, driver);
1094 	}
1095 }
1096 
1097 /**
1098  * @brief Add a device driver to a device class
1099  *
1100  * Add a device driver to a devclass. This is normally called
1101  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1102  * all devices in the devclass will be called to allow them to attempt
1103  * to re-probe any unmatched children.
1104  *
1105  * @param dc		the devclass to edit
1106  * @param driver	the driver to register
1107  */
1108 int
1109 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1110 {
1111 	driverlink_t dl;
1112 	const char *parentname;
1113 
1114 	PDEBUG(("%s", DRIVERNAME(driver)));
1115 
1116 	/* Don't allow invalid pass values. */
1117 	if (pass <= BUS_PASS_ROOT)
1118 		return (EINVAL);
1119 
1120 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1121 	if (!dl)
1122 		return (ENOMEM);
1123 
1124 	/*
1125 	 * Compile the driver's methods. Also increase the reference count
1126 	 * so that the class doesn't get freed when the last instance
1127 	 * goes. This means we can safely use static methods and avoids a
1128 	 * double-free in devclass_delete_driver.
1129 	 */
1130 	kobj_class_compile((kobj_class_t) driver);
1131 
1132 	/*
1133 	 * If the driver has any base classes, make the
1134 	 * devclass inherit from the devclass of the driver's
1135 	 * first base class. This will allow the system to
1136 	 * search for drivers in both devclasses for children
1137 	 * of a device using this driver.
1138 	 */
1139 	if (driver->baseclasses)
1140 		parentname = driver->baseclasses[0]->name;
1141 	else
1142 		parentname = NULL;
1143 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1144 
1145 	dl->driver = driver;
1146 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1147 	driver->refs++;		/* XXX: kobj_mtx */
1148 	dl->pass = pass;
1149 	driver_register_pass(dl);
1150 
1151 	if (device_frozen) {
1152 		dl->flags |= DL_DEFERRED_PROBE;
1153 	} else {
1154 		devclass_driver_added(dc, driver);
1155 	}
1156 	bus_data_generation_update();
1157 	return (0);
1158 }
1159 
1160 /**
1161  * @brief Register that a device driver has been deleted from a devclass
1162  *
1163  * Register that a device driver has been removed from a devclass.
1164  * This is called by devclass_delete_driver to accomplish the
1165  * recursive notification of all the children classes of busclass, as
1166  * well as busclass.  Each layer will attempt to detach the driver
1167  * from any devices that are children of the bus's devclass.  The function
1168  * will return an error if a device fails to detach.
1169  *
1170  * We do a full search here of the devclass list at each iteration
1171  * level to save storing children-lists in the devclass structure.  If
1172  * we ever move beyond a few dozen devices doing this, we may need to
1173  * reevaluate...
1174  *
1175  * @param busclass	the devclass of the parent bus
1176  * @param dc		the devclass of the driver being deleted
1177  * @param driver	the driver being deleted
1178  */
1179 static int
1180 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1181 {
1182 	devclass_t parent;
1183 	device_t dev;
1184 	int error, i;
1185 
1186 	/*
1187 	 * Disassociate from any devices.  We iterate through all the
1188 	 * devices in the devclass of the driver and detach any which are
1189 	 * using the driver and which have a parent in the devclass which
1190 	 * we are deleting from.
1191 	 *
1192 	 * Note that since a driver can be in multiple devclasses, we
1193 	 * should not detach devices which are not children of devices in
1194 	 * the affected devclass.
1195 	 *
1196 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1197 	 * generate later.
1198 	 */
1199 	for (i = 0; i < dc->maxunit; i++) {
1200 		if (dc->devices[i]) {
1201 			dev = dc->devices[i];
1202 			if (dev->driver == driver && dev->parent &&
1203 			    dev->parent->devclass == busclass) {
1204 				if ((error = device_detach(dev)) != 0)
1205 					return (error);
1206 				if (device_frozen) {
1207 					dev->flags &= ~DF_DONENOMATCH;
1208 					dev->flags |= DF_NEEDNOMATCH;
1209 				} else {
1210 					BUS_PROBE_NOMATCH(dev->parent, dev);
1211 					devnomatch(dev);
1212 					dev->flags |= DF_DONENOMATCH;
1213 				}
1214 			}
1215 		}
1216 	}
1217 
1218 	/*
1219 	 * Walk through the children classes.  Since we only keep a
1220 	 * single parent pointer around, we walk the entire list of
1221 	 * devclasses looking for children.  We set the
1222 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1223 	 * the parent, so we only walk the list for those devclasses
1224 	 * that have children.
1225 	 */
1226 	if (!(busclass->flags & DC_HAS_CHILDREN))
1227 		return (0);
1228 	parent = busclass;
1229 	TAILQ_FOREACH(busclass, &devclasses, link) {
1230 		if (busclass->parent == parent) {
1231 			error = devclass_driver_deleted(busclass, dc, driver);
1232 			if (error)
1233 				return (error);
1234 		}
1235 	}
1236 	return (0);
1237 }
1238 
1239 /**
1240  * @brief Delete a device driver from a device class
1241  *
1242  * Delete a device driver from a devclass. This is normally called
1243  * automatically by DRIVER_MODULE().
1244  *
1245  * If the driver is currently attached to any devices,
1246  * devclass_delete_driver() will first attempt to detach from each
1247  * device. If one of the detach calls fails, the driver will not be
1248  * deleted.
1249  *
1250  * @param dc		the devclass to edit
1251  * @param driver	the driver to unregister
1252  */
1253 int
1254 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1255 {
1256 	devclass_t dc = devclass_find(driver->name);
1257 	driverlink_t dl;
1258 	int error;
1259 
1260 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1261 
1262 	if (!dc)
1263 		return (0);
1264 
1265 	/*
1266 	 * Find the link structure in the bus' list of drivers.
1267 	 */
1268 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1269 		if (dl->driver == driver)
1270 			break;
1271 	}
1272 
1273 	if (!dl) {
1274 		PDEBUG(("%s not found in %s list", driver->name,
1275 		    busclass->name));
1276 		return (ENOENT);
1277 	}
1278 
1279 	error = devclass_driver_deleted(busclass, dc, driver);
1280 	if (error != 0)
1281 		return (error);
1282 
1283 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1284 	free(dl, M_BUS);
1285 
1286 	/* XXX: kobj_mtx */
1287 	driver->refs--;
1288 	if (driver->refs == 0)
1289 		kobj_class_free((kobj_class_t) driver);
1290 
1291 	bus_data_generation_update();
1292 	return (0);
1293 }
1294 
1295 /**
1296  * @brief Quiesces a set of device drivers from a device class
1297  *
1298  * Quiesce a device driver from a devclass. This is normally called
1299  * automatically by DRIVER_MODULE().
1300  *
1301  * If the driver is currently attached to any devices,
1302  * devclass_quiesece_driver() will first attempt to quiesce each
1303  * device.
1304  *
1305  * @param dc		the devclass to edit
1306  * @param driver	the driver to unregister
1307  */
1308 static int
1309 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1310 {
1311 	devclass_t dc = devclass_find(driver->name);
1312 	driverlink_t dl;
1313 	device_t dev;
1314 	int i;
1315 	int error;
1316 
1317 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1318 
1319 	if (!dc)
1320 		return (0);
1321 
1322 	/*
1323 	 * Find the link structure in the bus' list of drivers.
1324 	 */
1325 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1326 		if (dl->driver == driver)
1327 			break;
1328 	}
1329 
1330 	if (!dl) {
1331 		PDEBUG(("%s not found in %s list", driver->name,
1332 		    busclass->name));
1333 		return (ENOENT);
1334 	}
1335 
1336 	/*
1337 	 * Quiesce all devices.  We iterate through all the devices in
1338 	 * the devclass of the driver and quiesce any which are using
1339 	 * the driver and which have a parent in the devclass which we
1340 	 * are quiescing.
1341 	 *
1342 	 * Note that since a driver can be in multiple devclasses, we
1343 	 * should not quiesce devices which are not children of
1344 	 * devices in the affected devclass.
1345 	 */
1346 	for (i = 0; i < dc->maxunit; i++) {
1347 		if (dc->devices[i]) {
1348 			dev = dc->devices[i];
1349 			if (dev->driver == driver && dev->parent &&
1350 			    dev->parent->devclass == busclass) {
1351 				if ((error = device_quiesce(dev)) != 0)
1352 					return (error);
1353 			}
1354 		}
1355 	}
1356 
1357 	return (0);
1358 }
1359 
1360 /**
1361  * @internal
1362  */
1363 static driverlink_t
1364 devclass_find_driver_internal(devclass_t dc, const char *classname)
1365 {
1366 	driverlink_t dl;
1367 
1368 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1369 
1370 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1371 		if (!strcmp(dl->driver->name, classname))
1372 			return (dl);
1373 	}
1374 
1375 	PDEBUG(("not found"));
1376 	return (NULL);
1377 }
1378 
1379 /**
1380  * @brief Return the name of the devclass
1381  */
1382 const char *
1383 devclass_get_name(devclass_t dc)
1384 {
1385 	return (dc->name);
1386 }
1387 
1388 /**
1389  * @brief Find a device given a unit number
1390  *
1391  * @param dc		the devclass to search
1392  * @param unit		the unit number to search for
1393  *
1394  * @returns		the device with the given unit number or @c
1395  *			NULL if there is no such device
1396  */
1397 device_t
1398 devclass_get_device(devclass_t dc, int unit)
1399 {
1400 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1401 		return (NULL);
1402 	return (dc->devices[unit]);
1403 }
1404 
1405 /**
1406  * @brief Find the softc field of a device given a unit number
1407  *
1408  * @param dc		the devclass to search
1409  * @param unit		the unit number to search for
1410  *
1411  * @returns		the softc field of the device with the given
1412  *			unit number or @c NULL if there is no such
1413  *			device
1414  */
1415 void *
1416 devclass_get_softc(devclass_t dc, int unit)
1417 {
1418 	device_t dev;
1419 
1420 	dev = devclass_get_device(dc, unit);
1421 	if (!dev)
1422 		return (NULL);
1423 
1424 	return (device_get_softc(dev));
1425 }
1426 
1427 /**
1428  * @brief Get a list of devices in the devclass
1429  *
1430  * An array containing a list of all the devices in the given devclass
1431  * is allocated and returned in @p *devlistp. The number of devices
1432  * in the array is returned in @p *devcountp. The caller should free
1433  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1434  *
1435  * @param dc		the devclass to examine
1436  * @param devlistp	points at location for array pointer return
1437  *			value
1438  * @param devcountp	points at location for array size return value
1439  *
1440  * @retval 0		success
1441  * @retval ENOMEM	the array allocation failed
1442  */
1443 int
1444 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1445 {
1446 	int count, i;
1447 	device_t *list;
1448 
1449 	count = devclass_get_count(dc);
1450 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1451 	if (!list)
1452 		return (ENOMEM);
1453 
1454 	count = 0;
1455 	for (i = 0; i < dc->maxunit; i++) {
1456 		if (dc->devices[i]) {
1457 			list[count] = dc->devices[i];
1458 			count++;
1459 		}
1460 	}
1461 
1462 	*devlistp = list;
1463 	*devcountp = count;
1464 
1465 	return (0);
1466 }
1467 
1468 /**
1469  * @brief Get a list of drivers in the devclass
1470  *
1471  * An array containing a list of pointers to all the drivers in the
1472  * given devclass is allocated and returned in @p *listp.  The number
1473  * of drivers in the array is returned in @p *countp. The caller should
1474  * free the array using @c free(p, M_TEMP).
1475  *
1476  * @param dc		the devclass to examine
1477  * @param listp		gives location for array pointer return value
1478  * @param countp	gives location for number of array elements
1479  *			return value
1480  *
1481  * @retval 0		success
1482  * @retval ENOMEM	the array allocation failed
1483  */
1484 int
1485 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1486 {
1487 	driverlink_t dl;
1488 	driver_t **list;
1489 	int count;
1490 
1491 	count = 0;
1492 	TAILQ_FOREACH(dl, &dc->drivers, link)
1493 		count++;
1494 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1495 	if (list == NULL)
1496 		return (ENOMEM);
1497 
1498 	count = 0;
1499 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1500 		list[count] = dl->driver;
1501 		count++;
1502 	}
1503 	*listp = list;
1504 	*countp = count;
1505 
1506 	return (0);
1507 }
1508 
1509 /**
1510  * @brief Get the number of devices in a devclass
1511  *
1512  * @param dc		the devclass to examine
1513  */
1514 int
1515 devclass_get_count(devclass_t dc)
1516 {
1517 	int count, i;
1518 
1519 	count = 0;
1520 	for (i = 0; i < dc->maxunit; i++)
1521 		if (dc->devices[i])
1522 			count++;
1523 	return (count);
1524 }
1525 
1526 /**
1527  * @brief Get the maximum unit number used in a devclass
1528  *
1529  * Note that this is one greater than the highest currently-allocated
1530  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1531  * that not even the devclass has been allocated yet.
1532  *
1533  * @param dc		the devclass to examine
1534  */
1535 int
1536 devclass_get_maxunit(devclass_t dc)
1537 {
1538 	if (dc == NULL)
1539 		return (-1);
1540 	return (dc->maxunit);
1541 }
1542 
1543 /**
1544  * @brief Find a free unit number in a devclass
1545  *
1546  * This function searches for the first unused unit number greater
1547  * that or equal to @p unit.
1548  *
1549  * @param dc		the devclass to examine
1550  * @param unit		the first unit number to check
1551  */
1552 int
1553 devclass_find_free_unit(devclass_t dc, int unit)
1554 {
1555 	if (dc == NULL)
1556 		return (unit);
1557 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1558 		unit++;
1559 	return (unit);
1560 }
1561 
1562 /**
1563  * @brief Set the parent of a devclass
1564  *
1565  * The parent class is normally initialised automatically by
1566  * DRIVER_MODULE().
1567  *
1568  * @param dc		the devclass to edit
1569  * @param pdc		the new parent devclass
1570  */
1571 void
1572 devclass_set_parent(devclass_t dc, devclass_t pdc)
1573 {
1574 	dc->parent = pdc;
1575 }
1576 
1577 /**
1578  * @brief Get the parent of a devclass
1579  *
1580  * @param dc		the devclass to examine
1581  */
1582 devclass_t
1583 devclass_get_parent(devclass_t dc)
1584 {
1585 	return (dc->parent);
1586 }
1587 
1588 struct sysctl_ctx_list *
1589 devclass_get_sysctl_ctx(devclass_t dc)
1590 {
1591 	return (&dc->sysctl_ctx);
1592 }
1593 
1594 struct sysctl_oid *
1595 devclass_get_sysctl_tree(devclass_t dc)
1596 {
1597 	return (dc->sysctl_tree);
1598 }
1599 
1600 /**
1601  * @internal
1602  * @brief Allocate a unit number
1603  *
1604  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1605  * will do). The allocated unit number is returned in @p *unitp.
1606 
1607  * @param dc		the devclass to allocate from
1608  * @param unitp		points at the location for the allocated unit
1609  *			number
1610  *
1611  * @retval 0		success
1612  * @retval EEXIST	the requested unit number is already allocated
1613  * @retval ENOMEM	memory allocation failure
1614  */
1615 static int
1616 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1617 {
1618 	const char *s;
1619 	int unit = *unitp;
1620 
1621 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1622 
1623 	/* Ask the parent bus if it wants to wire this device. */
1624 	if (unit == -1)
1625 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1626 		    &unit);
1627 
1628 	/* If we were given a wired unit number, check for existing device */
1629 	/* XXX imp XXX */
1630 	if (unit != -1) {
1631 		if (unit >= 0 && unit < dc->maxunit &&
1632 		    dc->devices[unit] != NULL) {
1633 			if (bootverbose)
1634 				printf("%s: %s%d already exists; skipping it\n",
1635 				    dc->name, dc->name, *unitp);
1636 			return (EEXIST);
1637 		}
1638 	} else {
1639 		/* Unwired device, find the next available slot for it */
1640 		unit = 0;
1641 		for (unit = 0;; unit++) {
1642 			/* If this device slot is already in use, skip it. */
1643 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1644 				continue;
1645 
1646 			/* If there is an "at" hint for a unit then skip it. */
1647 			if (resource_string_value(dc->name, unit, "at", &s) ==
1648 			    0)
1649 				continue;
1650 
1651 			break;
1652 		}
1653 	}
1654 
1655 	/*
1656 	 * We've selected a unit beyond the length of the table, so let's
1657 	 * extend the table to make room for all units up to and including
1658 	 * this one.
1659 	 */
1660 	if (unit >= dc->maxunit) {
1661 		device_t *newlist, *oldlist;
1662 		int newsize;
1663 
1664 		oldlist = dc->devices;
1665 		newsize = roundup((unit + 1),
1666 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1667 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1668 		if (!newlist)
1669 			return (ENOMEM);
1670 		if (oldlist != NULL)
1671 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1672 		bzero(newlist + dc->maxunit,
1673 		    sizeof(device_t) * (newsize - dc->maxunit));
1674 		dc->devices = newlist;
1675 		dc->maxunit = newsize;
1676 		if (oldlist != NULL)
1677 			free(oldlist, M_BUS);
1678 	}
1679 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1680 
1681 	*unitp = unit;
1682 	return (0);
1683 }
1684 
1685 /**
1686  * @internal
1687  * @brief Add a device to a devclass
1688  *
1689  * A unit number is allocated for the device (using the device's
1690  * preferred unit number if any) and the device is registered in the
1691  * devclass. This allows the device to be looked up by its unit
1692  * number, e.g. by decoding a dev_t minor number.
1693  *
1694  * @param dc		the devclass to add to
1695  * @param dev		the device to add
1696  *
1697  * @retval 0		success
1698  * @retval EEXIST	the requested unit number is already allocated
1699  * @retval ENOMEM	memory allocation failure
1700  */
1701 static int
1702 devclass_add_device(devclass_t dc, device_t dev)
1703 {
1704 	int buflen, error;
1705 
1706 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1707 
1708 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1709 	if (buflen < 0)
1710 		return (ENOMEM);
1711 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1712 	if (!dev->nameunit)
1713 		return (ENOMEM);
1714 
1715 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1716 		free(dev->nameunit, M_BUS);
1717 		dev->nameunit = NULL;
1718 		return (error);
1719 	}
1720 	dc->devices[dev->unit] = dev;
1721 	dev->devclass = dc;
1722 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1723 
1724 	return (0);
1725 }
1726 
1727 /**
1728  * @internal
1729  * @brief Delete a device from a devclass
1730  *
1731  * The device is removed from the devclass's device list and its unit
1732  * number is freed.
1733 
1734  * @param dc		the devclass to delete from
1735  * @param dev		the device to delete
1736  *
1737  * @retval 0		success
1738  */
1739 static int
1740 devclass_delete_device(devclass_t dc, device_t dev)
1741 {
1742 	if (!dc || !dev)
1743 		return (0);
1744 
1745 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1746 
1747 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1748 		panic("devclass_delete_device: inconsistent device class");
1749 	dc->devices[dev->unit] = NULL;
1750 	if (dev->flags & DF_WILDCARD)
1751 		dev->unit = -1;
1752 	dev->devclass = NULL;
1753 	free(dev->nameunit, M_BUS);
1754 	dev->nameunit = NULL;
1755 
1756 	return (0);
1757 }
1758 
1759 /**
1760  * @internal
1761  * @brief Make a new device and add it as a child of @p parent
1762  *
1763  * @param parent	the parent of the new device
1764  * @param name		the devclass name of the new device or @c NULL
1765  *			to leave the devclass unspecified
1766  * @parem unit		the unit number of the new device of @c -1 to
1767  *			leave the unit number unspecified
1768  *
1769  * @returns the new device
1770  */
1771 static device_t
1772 make_device(device_t parent, const char *name, int unit)
1773 {
1774 	device_t dev;
1775 	devclass_t dc;
1776 
1777 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1778 
1779 	if (name) {
1780 		dc = devclass_find_internal(name, NULL, TRUE);
1781 		if (!dc) {
1782 			printf("make_device: can't find device class %s\n",
1783 			    name);
1784 			return (NULL);
1785 		}
1786 	} else {
1787 		dc = NULL;
1788 	}
1789 
1790 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1791 	if (!dev)
1792 		return (NULL);
1793 
1794 	dev->parent = parent;
1795 	TAILQ_INIT(&dev->children);
1796 	kobj_init((kobj_t) dev, &null_class);
1797 	dev->driver = NULL;
1798 	dev->devclass = NULL;
1799 	dev->unit = unit;
1800 	dev->nameunit = NULL;
1801 	dev->desc = NULL;
1802 	dev->busy = 0;
1803 	dev->devflags = 0;
1804 	dev->flags = DF_ENABLED;
1805 	dev->order = 0;
1806 	if (unit == -1)
1807 		dev->flags |= DF_WILDCARD;
1808 	if (name) {
1809 		dev->flags |= DF_FIXEDCLASS;
1810 		if (devclass_add_device(dc, dev)) {
1811 			kobj_delete((kobj_t) dev, M_BUS);
1812 			return (NULL);
1813 		}
1814 	}
1815 	if (parent != NULL && device_has_quiet_children(parent))
1816 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1817 	dev->ivars = NULL;
1818 	dev->softc = NULL;
1819 
1820 	dev->state = DS_NOTPRESENT;
1821 
1822 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1823 	bus_data_generation_update();
1824 
1825 	return (dev);
1826 }
1827 
1828 /**
1829  * @internal
1830  * @brief Print a description of a device.
1831  */
1832 static int
1833 device_print_child(device_t dev, device_t child)
1834 {
1835 	int retval = 0;
1836 
1837 	if (device_is_alive(child))
1838 		retval += BUS_PRINT_CHILD(dev, child);
1839 	else
1840 		retval += device_printf(child, " not found\n");
1841 
1842 	return (retval);
1843 }
1844 
1845 /**
1846  * @brief Create a new device
1847  *
1848  * This creates a new device and adds it as a child of an existing
1849  * parent device. The new device will be added after the last existing
1850  * child with order zero.
1851  *
1852  * @param dev		the device which will be the parent of the
1853  *			new child device
1854  * @param name		devclass name for new device or @c NULL if not
1855  *			specified
1856  * @param unit		unit number for new device or @c -1 if not
1857  *			specified
1858  *
1859  * @returns		the new device
1860  */
1861 device_t
1862 device_add_child(device_t dev, const char *name, int unit)
1863 {
1864 	return (device_add_child_ordered(dev, 0, name, unit));
1865 }
1866 
1867 /**
1868  * @brief Create a new device
1869  *
1870  * This creates a new device and adds it as a child of an existing
1871  * parent device. The new device will be added after the last existing
1872  * child with the same order.
1873  *
1874  * @param dev		the device which will be the parent of the
1875  *			new child device
1876  * @param order		a value which is used to partially sort the
1877  *			children of @p dev - devices created using
1878  *			lower values of @p order appear first in @p
1879  *			dev's list of children
1880  * @param name		devclass name for new device or @c NULL if not
1881  *			specified
1882  * @param unit		unit number for new device or @c -1 if not
1883  *			specified
1884  *
1885  * @returns		the new device
1886  */
1887 device_t
1888 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1889 {
1890 	device_t child;
1891 	device_t place;
1892 
1893 	PDEBUG(("%s at %s with order %u as unit %d",
1894 	    name, DEVICENAME(dev), order, unit));
1895 	KASSERT(name != NULL || unit == -1,
1896 	    ("child device with wildcard name and specific unit number"));
1897 
1898 	child = make_device(dev, name, unit);
1899 	if (child == NULL)
1900 		return (child);
1901 	child->order = order;
1902 
1903 	TAILQ_FOREACH(place, &dev->children, link) {
1904 		if (place->order > order)
1905 			break;
1906 	}
1907 
1908 	if (place) {
1909 		/*
1910 		 * The device 'place' is the first device whose order is
1911 		 * greater than the new child.
1912 		 */
1913 		TAILQ_INSERT_BEFORE(place, child, link);
1914 	} else {
1915 		/*
1916 		 * The new child's order is greater or equal to the order of
1917 		 * any existing device. Add the child to the tail of the list.
1918 		 */
1919 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1920 	}
1921 
1922 	bus_data_generation_update();
1923 	return (child);
1924 }
1925 
1926 /**
1927  * @brief Delete a device
1928  *
1929  * This function deletes a device along with all of its children. If
1930  * the device currently has a driver attached to it, the device is
1931  * detached first using device_detach().
1932  *
1933  * @param dev		the parent device
1934  * @param child		the device to delete
1935  *
1936  * @retval 0		success
1937  * @retval non-zero	a unit error code describing the error
1938  */
1939 int
1940 device_delete_child(device_t dev, device_t child)
1941 {
1942 	int error;
1943 	device_t grandchild;
1944 
1945 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1946 
1947 	/* detach parent before deleting children, if any */
1948 	if ((error = device_detach(child)) != 0)
1949 		return (error);
1950 
1951 	/* remove children second */
1952 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1953 		error = device_delete_child(child, grandchild);
1954 		if (error)
1955 			return (error);
1956 	}
1957 
1958 	if (child->devclass)
1959 		devclass_delete_device(child->devclass, child);
1960 	if (child->parent)
1961 		BUS_CHILD_DELETED(dev, child);
1962 	TAILQ_REMOVE(&dev->children, child, link);
1963 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1964 	kobj_delete((kobj_t) child, M_BUS);
1965 
1966 	bus_data_generation_update();
1967 	return (0);
1968 }
1969 
1970 /**
1971  * @brief Delete all children devices of the given device, if any.
1972  *
1973  * This function deletes all children devices of the given device, if
1974  * any, using the device_delete_child() function for each device it
1975  * finds. If a child device cannot be deleted, this function will
1976  * return an error code.
1977  *
1978  * @param dev		the parent device
1979  *
1980  * @retval 0		success
1981  * @retval non-zero	a device would not detach
1982  */
1983 int
1984 device_delete_children(device_t dev)
1985 {
1986 	device_t child;
1987 	int error;
1988 
1989 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
1990 
1991 	error = 0;
1992 
1993 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
1994 		error = device_delete_child(dev, child);
1995 		if (error) {
1996 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
1997 			break;
1998 		}
1999 	}
2000 	return (error);
2001 }
2002 
2003 /**
2004  * @brief Find a device given a unit number
2005  *
2006  * This is similar to devclass_get_devices() but only searches for
2007  * devices which have @p dev as a parent.
2008  *
2009  * @param dev		the parent device to search
2010  * @param unit		the unit number to search for.  If the unit is -1,
2011  *			return the first child of @p dev which has name
2012  *			@p classname (that is, the one with the lowest unit.)
2013  *
2014  * @returns		the device with the given unit number or @c
2015  *			NULL if there is no such device
2016  */
2017 device_t
2018 device_find_child(device_t dev, const char *classname, int unit)
2019 {
2020 	devclass_t dc;
2021 	device_t child;
2022 
2023 	dc = devclass_find(classname);
2024 	if (!dc)
2025 		return (NULL);
2026 
2027 	if (unit != -1) {
2028 		child = devclass_get_device(dc, unit);
2029 		if (child && child->parent == dev)
2030 			return (child);
2031 	} else {
2032 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2033 			child = devclass_get_device(dc, unit);
2034 			if (child && child->parent == dev)
2035 				return (child);
2036 		}
2037 	}
2038 	return (NULL);
2039 }
2040 
2041 /**
2042  * @internal
2043  */
2044 static driverlink_t
2045 first_matching_driver(devclass_t dc, device_t dev)
2046 {
2047 	if (dev->devclass)
2048 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2049 	return (TAILQ_FIRST(&dc->drivers));
2050 }
2051 
2052 /**
2053  * @internal
2054  */
2055 static driverlink_t
2056 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2057 {
2058 	if (dev->devclass) {
2059 		driverlink_t dl;
2060 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2061 			if (!strcmp(dev->devclass->name, dl->driver->name))
2062 				return (dl);
2063 		return (NULL);
2064 	}
2065 	return (TAILQ_NEXT(last, link));
2066 }
2067 
2068 /**
2069  * @internal
2070  */
2071 int
2072 device_probe_child(device_t dev, device_t child)
2073 {
2074 	devclass_t dc;
2075 	driverlink_t best = NULL;
2076 	driverlink_t dl;
2077 	int result, pri = 0;
2078 	/* We should preserve the devclass (or lack of) set by the bus. */
2079 	int hasclass = (child->devclass != NULL);
2080 
2081 	GIANT_REQUIRED;
2082 
2083 	dc = dev->devclass;
2084 	if (!dc)
2085 		panic("device_probe_child: parent device has no devclass");
2086 
2087 	/*
2088 	 * If the state is already probed, then return.
2089 	 */
2090 	if (child->state == DS_ALIVE)
2091 		return (0);
2092 
2093 	for (; dc; dc = dc->parent) {
2094 		for (dl = first_matching_driver(dc, child);
2095 		     dl;
2096 		     dl = next_matching_driver(dc, child, dl)) {
2097 			/* If this driver's pass is too high, then ignore it. */
2098 			if (dl->pass > bus_current_pass)
2099 				continue;
2100 
2101 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2102 			result = device_set_driver(child, dl->driver);
2103 			if (result == ENOMEM)
2104 				return (result);
2105 			else if (result != 0)
2106 				continue;
2107 			if (!hasclass) {
2108 				if (device_set_devclass(child,
2109 				    dl->driver->name) != 0) {
2110 					char const * devname =
2111 					    device_get_name(child);
2112 					if (devname == NULL)
2113 						devname = "(unknown)";
2114 					printf("driver bug: Unable to set "
2115 					    "devclass (class: %s "
2116 					    "devname: %s)\n",
2117 					    dl->driver->name,
2118 					    devname);
2119 					(void)device_set_driver(child, NULL);
2120 					continue;
2121 				}
2122 			}
2123 
2124 			/* Fetch any flags for the device before probing. */
2125 			resource_int_value(dl->driver->name, child->unit,
2126 			    "flags", &child->devflags);
2127 
2128 			result = DEVICE_PROBE(child);
2129 
2130 			/*
2131 			 * If the driver returns SUCCESS, there can be
2132 			 * no higher match for this device.
2133 			 */
2134 			if (result == 0) {
2135 				best = dl;
2136 				pri = 0;
2137 				break;
2138 			}
2139 
2140 			/* Reset flags and devclass before the next probe. */
2141 			child->devflags = 0;
2142 			if (!hasclass)
2143 				(void)device_set_devclass(child, NULL);
2144 
2145 			/*
2146 			 * Reset DF_QUIET in case this driver doesn't
2147 			 * end up as the best driver.
2148 			 */
2149 			device_verbose(child);
2150 
2151 			/*
2152 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2153 			 * only match on devices whose driver was explicitly
2154 			 * specified.
2155 			 */
2156 			if (result <= BUS_PROBE_NOWILDCARD &&
2157 			    !(child->flags & DF_FIXEDCLASS)) {
2158 				result = ENXIO;
2159 			}
2160 
2161 			/*
2162 			 * The driver returned an error so it
2163 			 * certainly doesn't match.
2164 			 */
2165 			if (result > 0) {
2166 				(void)device_set_driver(child, NULL);
2167 				continue;
2168 			}
2169 
2170 			/*
2171 			 * A priority lower than SUCCESS, remember the
2172 			 * best matching driver. Initialise the value
2173 			 * of pri for the first match.
2174 			 */
2175 			if (best == NULL || result > pri) {
2176 				best = dl;
2177 				pri = result;
2178 				continue;
2179 			}
2180 		}
2181 		/*
2182 		 * If we have an unambiguous match in this devclass,
2183 		 * don't look in the parent.
2184 		 */
2185 		if (best && pri == 0)
2186 			break;
2187 	}
2188 
2189 	if (best == NULL)
2190 		return (ENXIO);
2191 
2192 	/*
2193 	 * If we found a driver, change state and initialise the devclass.
2194 	 */
2195 	if (pri < 0) {
2196 		/* Set the winning driver, devclass, and flags. */
2197 		result = device_set_driver(child, best->driver);
2198 		if (result != 0)
2199 			return (result);
2200 		if (!child->devclass) {
2201 			result = device_set_devclass(child, best->driver->name);
2202 			if (result != 0) {
2203 				(void)device_set_driver(child, NULL);
2204 				return (result);
2205 			}
2206 		}
2207 		resource_int_value(best->driver->name, child->unit,
2208 		    "flags", &child->devflags);
2209 
2210 		/*
2211 		 * A bit bogus. Call the probe method again to make sure
2212 		 * that we have the right description.
2213 		 */
2214 		result = DEVICE_PROBE(child);
2215 		if (result > 0) {
2216 			if (!hasclass)
2217 				(void)device_set_devclass(child, NULL);
2218 			(void)device_set_driver(child, NULL);
2219 			return (result);
2220 		}
2221 	}
2222 
2223 	child->state = DS_ALIVE;
2224 	bus_data_generation_update();
2225 	return (0);
2226 }
2227 
2228 /**
2229  * @brief Return the parent of a device
2230  */
2231 device_t
2232 device_get_parent(device_t dev)
2233 {
2234 	return (dev->parent);
2235 }
2236 
2237 /**
2238  * @brief Get a list of children of a device
2239  *
2240  * An array containing a list of all the children of the given device
2241  * is allocated and returned in @p *devlistp. The number of devices
2242  * in the array is returned in @p *devcountp. The caller should free
2243  * the array using @c free(p, M_TEMP).
2244  *
2245  * @param dev		the device to examine
2246  * @param devlistp	points at location for array pointer return
2247  *			value
2248  * @param devcountp	points at location for array size return value
2249  *
2250  * @retval 0		success
2251  * @retval ENOMEM	the array allocation failed
2252  */
2253 int
2254 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2255 {
2256 	int count;
2257 	device_t child;
2258 	device_t *list;
2259 
2260 	count = 0;
2261 	TAILQ_FOREACH(child, &dev->children, link) {
2262 		count++;
2263 	}
2264 	if (count == 0) {
2265 		*devlistp = NULL;
2266 		*devcountp = 0;
2267 		return (0);
2268 	}
2269 
2270 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2271 	if (!list)
2272 		return (ENOMEM);
2273 
2274 	count = 0;
2275 	TAILQ_FOREACH(child, &dev->children, link) {
2276 		list[count] = child;
2277 		count++;
2278 	}
2279 
2280 	*devlistp = list;
2281 	*devcountp = count;
2282 
2283 	return (0);
2284 }
2285 
2286 /**
2287  * @brief Return the current driver for the device or @c NULL if there
2288  * is no driver currently attached
2289  */
2290 driver_t *
2291 device_get_driver(device_t dev)
2292 {
2293 	return (dev->driver);
2294 }
2295 
2296 /**
2297  * @brief Return the current devclass for the device or @c NULL if
2298  * there is none.
2299  */
2300 devclass_t
2301 device_get_devclass(device_t dev)
2302 {
2303 	return (dev->devclass);
2304 }
2305 
2306 /**
2307  * @brief Return the name of the device's devclass or @c NULL if there
2308  * is none.
2309  */
2310 const char *
2311 device_get_name(device_t dev)
2312 {
2313 	if (dev != NULL && dev->devclass)
2314 		return (devclass_get_name(dev->devclass));
2315 	return (NULL);
2316 }
2317 
2318 /**
2319  * @brief Return a string containing the device's devclass name
2320  * followed by an ascii representation of the device's unit number
2321  * (e.g. @c "foo2").
2322  */
2323 const char *
2324 device_get_nameunit(device_t dev)
2325 {
2326 	return (dev->nameunit);
2327 }
2328 
2329 /**
2330  * @brief Return the device's unit number.
2331  */
2332 int
2333 device_get_unit(device_t dev)
2334 {
2335 	return (dev->unit);
2336 }
2337 
2338 /**
2339  * @brief Return the device's description string
2340  */
2341 const char *
2342 device_get_desc(device_t dev)
2343 {
2344 	return (dev->desc);
2345 }
2346 
2347 /**
2348  * @brief Return the device's flags
2349  */
2350 uint32_t
2351 device_get_flags(device_t dev)
2352 {
2353 	return (dev->devflags);
2354 }
2355 
2356 struct sysctl_ctx_list *
2357 device_get_sysctl_ctx(device_t dev)
2358 {
2359 	return (&dev->sysctl_ctx);
2360 }
2361 
2362 struct sysctl_oid *
2363 device_get_sysctl_tree(device_t dev)
2364 {
2365 	return (dev->sysctl_tree);
2366 }
2367 
2368 /**
2369  * @brief Print the name of the device followed by a colon and a space
2370  *
2371  * @returns the number of characters printed
2372  */
2373 int
2374 device_print_prettyname(device_t dev)
2375 {
2376 	const char *name = device_get_name(dev);
2377 
2378 	if (name == NULL)
2379 		return (printf("unknown: "));
2380 	return (printf("%s%d: ", name, device_get_unit(dev)));
2381 }
2382 
2383 /**
2384  * @brief Print the name of the device followed by a colon, a space
2385  * and the result of calling vprintf() with the value of @p fmt and
2386  * the following arguments.
2387  *
2388  * @returns the number of characters printed
2389  */
2390 int
2391 device_printf(device_t dev, const char * fmt, ...)
2392 {
2393 	char buf[128];
2394 	struct sbuf sb;
2395 	const char *name;
2396 	va_list ap;
2397 	size_t retval;
2398 
2399 	retval = 0;
2400 
2401 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2402 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2403 
2404 	name = device_get_name(dev);
2405 
2406 	if (name == NULL)
2407 		sbuf_cat(&sb, "unknown: ");
2408 	else
2409 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2410 
2411 	va_start(ap, fmt);
2412 	sbuf_vprintf(&sb, fmt, ap);
2413 	va_end(ap);
2414 
2415 	sbuf_finish(&sb);
2416 	sbuf_delete(&sb);
2417 
2418 	return (retval);
2419 }
2420 
2421 /**
2422  * @brief Print the name of the device followed by a colon, a space
2423  * and the result of calling log() with the value of @p fmt and
2424  * the following arguments.
2425  *
2426  * @returns the number of characters printed
2427  */
2428 int
2429 device_log(device_t dev, int pri, const char * fmt, ...)
2430 {
2431 	char buf[128];
2432 	struct sbuf sb;
2433 	const char *name;
2434 	va_list ap;
2435 	size_t retval;
2436 
2437 	retval = 0;
2438 
2439 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2440 
2441 	name = device_get_name(dev);
2442 
2443 	if (name == NULL)
2444 		sbuf_cat(&sb, "unknown: ");
2445 	else
2446 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2447 
2448 	va_start(ap, fmt);
2449 	sbuf_vprintf(&sb, fmt, ap);
2450 	va_end(ap);
2451 
2452 	sbuf_finish(&sb);
2453 
2454 	log(pri, "%.*s", (int) sbuf_len(&sb), sbuf_data(&sb));
2455 	retval = sbuf_len(&sb);
2456 
2457 	sbuf_delete(&sb);
2458 
2459 	return (retval);
2460 }
2461 
2462 /**
2463  * @internal
2464  */
2465 static void
2466 device_set_desc_internal(device_t dev, const char* desc, int copy)
2467 {
2468 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2469 		free(dev->desc, M_BUS);
2470 		dev->flags &= ~DF_DESCMALLOCED;
2471 		dev->desc = NULL;
2472 	}
2473 
2474 	if (copy && desc) {
2475 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2476 		if (dev->desc) {
2477 			strcpy(dev->desc, desc);
2478 			dev->flags |= DF_DESCMALLOCED;
2479 		}
2480 	} else {
2481 		/* Avoid a -Wcast-qual warning */
2482 		dev->desc = (char *)(uintptr_t) desc;
2483 	}
2484 
2485 	bus_data_generation_update();
2486 }
2487 
2488 /**
2489  * @brief Set the device's description
2490  *
2491  * The value of @c desc should be a string constant that will not
2492  * change (at least until the description is changed in a subsequent
2493  * call to device_set_desc() or device_set_desc_copy()).
2494  */
2495 void
2496 device_set_desc(device_t dev, const char* desc)
2497 {
2498 	device_set_desc_internal(dev, desc, FALSE);
2499 }
2500 
2501 /**
2502  * @brief Set the device's description
2503  *
2504  * The string pointed to by @c desc is copied. Use this function if
2505  * the device description is generated, (e.g. with sprintf()).
2506  */
2507 void
2508 device_set_desc_copy(device_t dev, const char* desc)
2509 {
2510 	device_set_desc_internal(dev, desc, TRUE);
2511 }
2512 
2513 /**
2514  * @brief Set the device's flags
2515  */
2516 void
2517 device_set_flags(device_t dev, uint32_t flags)
2518 {
2519 	dev->devflags = flags;
2520 }
2521 
2522 /**
2523  * @brief Return the device's softc field
2524  *
2525  * The softc is allocated and zeroed when a driver is attached, based
2526  * on the size field of the driver.
2527  */
2528 void *
2529 device_get_softc(device_t dev)
2530 {
2531 	return (dev->softc);
2532 }
2533 
2534 /**
2535  * @brief Set the device's softc field
2536  *
2537  * Most drivers do not need to use this since the softc is allocated
2538  * automatically when the driver is attached.
2539  */
2540 void
2541 device_set_softc(device_t dev, void *softc)
2542 {
2543 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2544 		free(dev->softc, M_BUS_SC);
2545 	dev->softc = softc;
2546 	if (dev->softc)
2547 		dev->flags |= DF_EXTERNALSOFTC;
2548 	else
2549 		dev->flags &= ~DF_EXTERNALSOFTC;
2550 }
2551 
2552 /**
2553  * @brief Free claimed softc
2554  *
2555  * Most drivers do not need to use this since the softc is freed
2556  * automatically when the driver is detached.
2557  */
2558 void
2559 device_free_softc(void *softc)
2560 {
2561 	free(softc, M_BUS_SC);
2562 }
2563 
2564 /**
2565  * @brief Claim softc
2566  *
2567  * This function can be used to let the driver free the automatically
2568  * allocated softc using "device_free_softc()". This function is
2569  * useful when the driver is refcounting the softc and the softc
2570  * cannot be freed when the "device_detach" method is called.
2571  */
2572 void
2573 device_claim_softc(device_t dev)
2574 {
2575 	if (dev->softc)
2576 		dev->flags |= DF_EXTERNALSOFTC;
2577 	else
2578 		dev->flags &= ~DF_EXTERNALSOFTC;
2579 }
2580 
2581 /**
2582  * @brief Get the device's ivars field
2583  *
2584  * The ivars field is used by the parent device to store per-device
2585  * state (e.g. the physical location of the device or a list of
2586  * resources).
2587  */
2588 void *
2589 device_get_ivars(device_t dev)
2590 {
2591 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2592 	return (dev->ivars);
2593 }
2594 
2595 /**
2596  * @brief Set the device's ivars field
2597  */
2598 void
2599 device_set_ivars(device_t dev, void * ivars)
2600 {
2601 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2602 	dev->ivars = ivars;
2603 }
2604 
2605 /**
2606  * @brief Return the device's state
2607  */
2608 device_state_t
2609 device_get_state(device_t dev)
2610 {
2611 	return (dev->state);
2612 }
2613 
2614 /**
2615  * @brief Set the DF_ENABLED flag for the device
2616  */
2617 void
2618 device_enable(device_t dev)
2619 {
2620 	dev->flags |= DF_ENABLED;
2621 }
2622 
2623 /**
2624  * @brief Clear the DF_ENABLED flag for the device
2625  */
2626 void
2627 device_disable(device_t dev)
2628 {
2629 	dev->flags &= ~DF_ENABLED;
2630 }
2631 
2632 /**
2633  * @brief Increment the busy counter for the device
2634  */
2635 void
2636 device_busy(device_t dev)
2637 {
2638 
2639 	/*
2640 	 * Mark the device as busy, recursively up the tree if this busy count
2641 	 * goes 0->1.
2642 	 */
2643 	if (refcount_acquire(&dev->busy) == 0 && dev->parent != NULL)
2644 		device_busy(dev->parent);
2645 }
2646 
2647 /**
2648  * @brief Decrement the busy counter for the device
2649  */
2650 void
2651 device_unbusy(device_t dev)
2652 {
2653 
2654 	/*
2655 	 * Mark the device as unbsy, recursively if this is the last busy count.
2656 	 */
2657 	if (refcount_release(&dev->busy) && dev->parent != NULL)
2658 		device_unbusy(dev->parent);
2659 }
2660 
2661 /**
2662  * @brief Set the DF_QUIET flag for the device
2663  */
2664 void
2665 device_quiet(device_t dev)
2666 {
2667 	dev->flags |= DF_QUIET;
2668 }
2669 
2670 /**
2671  * @brief Set the DF_QUIET_CHILDREN flag for the device
2672  */
2673 void
2674 device_quiet_children(device_t dev)
2675 {
2676 	dev->flags |= DF_QUIET_CHILDREN;
2677 }
2678 
2679 /**
2680  * @brief Clear the DF_QUIET flag for the device
2681  */
2682 void
2683 device_verbose(device_t dev)
2684 {
2685 	dev->flags &= ~DF_QUIET;
2686 }
2687 
2688 ssize_t
2689 device_get_property(device_t dev, const char *prop, void *val, size_t sz)
2690 {
2691 	device_t bus = device_get_parent(dev);
2692 
2693 	return (BUS_GET_PROPERTY(bus, dev, prop, val, sz));
2694 }
2695 
2696 bool
2697 device_has_property(device_t dev, const char *prop)
2698 {
2699 	return (device_get_property(dev, prop, NULL, 0) >= 0);
2700 }
2701 
2702 /**
2703  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2704  */
2705 int
2706 device_has_quiet_children(device_t dev)
2707 {
2708 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2709 }
2710 
2711 /**
2712  * @brief Return non-zero if the DF_QUIET flag is set on the device
2713  */
2714 int
2715 device_is_quiet(device_t dev)
2716 {
2717 	return ((dev->flags & DF_QUIET) != 0);
2718 }
2719 
2720 /**
2721  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2722  */
2723 int
2724 device_is_enabled(device_t dev)
2725 {
2726 	return ((dev->flags & DF_ENABLED) != 0);
2727 }
2728 
2729 /**
2730  * @brief Return non-zero if the device was successfully probed
2731  */
2732 int
2733 device_is_alive(device_t dev)
2734 {
2735 	return (dev->state >= DS_ALIVE);
2736 }
2737 
2738 /**
2739  * @brief Return non-zero if the device currently has a driver
2740  * attached to it
2741  */
2742 int
2743 device_is_attached(device_t dev)
2744 {
2745 	return (dev->state >= DS_ATTACHED);
2746 }
2747 
2748 /**
2749  * @brief Return non-zero if the device is currently suspended.
2750  */
2751 int
2752 device_is_suspended(device_t dev)
2753 {
2754 	return ((dev->flags & DF_SUSPENDED) != 0);
2755 }
2756 
2757 /**
2758  * @brief Set the devclass of a device
2759  * @see devclass_add_device().
2760  */
2761 int
2762 device_set_devclass(device_t dev, const char *classname)
2763 {
2764 	devclass_t dc;
2765 	int error;
2766 
2767 	if (!classname) {
2768 		if (dev->devclass)
2769 			devclass_delete_device(dev->devclass, dev);
2770 		return (0);
2771 	}
2772 
2773 	if (dev->devclass) {
2774 		printf("device_set_devclass: device class already set\n");
2775 		return (EINVAL);
2776 	}
2777 
2778 	dc = devclass_find_internal(classname, NULL, TRUE);
2779 	if (!dc)
2780 		return (ENOMEM);
2781 
2782 	error = devclass_add_device(dc, dev);
2783 
2784 	bus_data_generation_update();
2785 	return (error);
2786 }
2787 
2788 /**
2789  * @brief Set the devclass of a device and mark the devclass fixed.
2790  * @see device_set_devclass()
2791  */
2792 int
2793 device_set_devclass_fixed(device_t dev, const char *classname)
2794 {
2795 	int error;
2796 
2797 	if (classname == NULL)
2798 		return (EINVAL);
2799 
2800 	error = device_set_devclass(dev, classname);
2801 	if (error)
2802 		return (error);
2803 	dev->flags |= DF_FIXEDCLASS;
2804 	return (0);
2805 }
2806 
2807 /**
2808  * @brief Query the device to determine if it's of a fixed devclass
2809  * @see device_set_devclass_fixed()
2810  */
2811 bool
2812 device_is_devclass_fixed(device_t dev)
2813 {
2814 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2815 }
2816 
2817 /**
2818  * @brief Set the driver of a device
2819  *
2820  * @retval 0		success
2821  * @retval EBUSY	the device already has a driver attached
2822  * @retval ENOMEM	a memory allocation failure occurred
2823  */
2824 int
2825 device_set_driver(device_t dev, driver_t *driver)
2826 {
2827 	int domain;
2828 	struct domainset *policy;
2829 
2830 	if (dev->state >= DS_ATTACHED)
2831 		return (EBUSY);
2832 
2833 	if (dev->driver == driver)
2834 		return (0);
2835 
2836 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2837 		free(dev->softc, M_BUS_SC);
2838 		dev->softc = NULL;
2839 	}
2840 	device_set_desc(dev, NULL);
2841 	kobj_delete((kobj_t) dev, NULL);
2842 	dev->driver = driver;
2843 	if (driver) {
2844 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2845 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2846 			if (bus_get_domain(dev, &domain) == 0)
2847 				policy = DOMAINSET_PREF(domain);
2848 			else
2849 				policy = DOMAINSET_RR();
2850 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2851 			    policy, M_NOWAIT | M_ZERO);
2852 			if (!dev->softc) {
2853 				kobj_delete((kobj_t) dev, NULL);
2854 				kobj_init((kobj_t) dev, &null_class);
2855 				dev->driver = NULL;
2856 				return (ENOMEM);
2857 			}
2858 		}
2859 	} else {
2860 		kobj_init((kobj_t) dev, &null_class);
2861 	}
2862 
2863 	bus_data_generation_update();
2864 	return (0);
2865 }
2866 
2867 /**
2868  * @brief Probe a device, and return this status.
2869  *
2870  * This function is the core of the device autoconfiguration
2871  * system. Its purpose is to select a suitable driver for a device and
2872  * then call that driver to initialise the hardware appropriately. The
2873  * driver is selected by calling the DEVICE_PROBE() method of a set of
2874  * candidate drivers and then choosing the driver which returned the
2875  * best value. This driver is then attached to the device using
2876  * device_attach().
2877  *
2878  * The set of suitable drivers is taken from the list of drivers in
2879  * the parent device's devclass. If the device was originally created
2880  * with a specific class name (see device_add_child()), only drivers
2881  * with that name are probed, otherwise all drivers in the devclass
2882  * are probed. If no drivers return successful probe values in the
2883  * parent devclass, the search continues in the parent of that
2884  * devclass (see devclass_get_parent()) if any.
2885  *
2886  * @param dev		the device to initialise
2887  *
2888  * @retval 0		success
2889  * @retval ENXIO	no driver was found
2890  * @retval ENOMEM	memory allocation failure
2891  * @retval non-zero	some other unix error code
2892  * @retval -1		Device already attached
2893  */
2894 int
2895 device_probe(device_t dev)
2896 {
2897 	int error;
2898 
2899 	GIANT_REQUIRED;
2900 
2901 	if (dev->state >= DS_ALIVE)
2902 		return (-1);
2903 
2904 	if (!(dev->flags & DF_ENABLED)) {
2905 		if (bootverbose && device_get_name(dev) != NULL) {
2906 			device_print_prettyname(dev);
2907 			printf("not probed (disabled)\n");
2908 		}
2909 		return (-1);
2910 	}
2911 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2912 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2913 		    !(dev->flags & DF_DONENOMATCH)) {
2914 			BUS_PROBE_NOMATCH(dev->parent, dev);
2915 			devnomatch(dev);
2916 			dev->flags |= DF_DONENOMATCH;
2917 		}
2918 		return (error);
2919 	}
2920 	return (0);
2921 }
2922 
2923 /**
2924  * @brief Probe a device and attach a driver if possible
2925  *
2926  * calls device_probe() and attaches if that was successful.
2927  */
2928 int
2929 device_probe_and_attach(device_t dev)
2930 {
2931 	int error;
2932 
2933 	GIANT_REQUIRED;
2934 
2935 	error = device_probe(dev);
2936 	if (error == -1)
2937 		return (0);
2938 	else if (error != 0)
2939 		return (error);
2940 
2941 	CURVNET_SET_QUIET(vnet0);
2942 	error = device_attach(dev);
2943 	CURVNET_RESTORE();
2944 	return error;
2945 }
2946 
2947 /**
2948  * @brief Attach a device driver to a device
2949  *
2950  * This function is a wrapper around the DEVICE_ATTACH() driver
2951  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2952  * device's sysctl tree, optionally prints a description of the device
2953  * and queues a notification event for user-based device management
2954  * services.
2955  *
2956  * Normally this function is only called internally from
2957  * device_probe_and_attach().
2958  *
2959  * @param dev		the device to initialise
2960  *
2961  * @retval 0		success
2962  * @retval ENXIO	no driver was found
2963  * @retval ENOMEM	memory allocation failure
2964  * @retval non-zero	some other unix error code
2965  */
2966 int
2967 device_attach(device_t dev)
2968 {
2969 	uint64_t attachtime;
2970 	uint16_t attachentropy;
2971 	int error;
2972 
2973 	if (resource_disabled(dev->driver->name, dev->unit)) {
2974 		device_disable(dev);
2975 		if (bootverbose)
2976 			 device_printf(dev, "disabled via hints entry\n");
2977 		return (ENXIO);
2978 	}
2979 
2980 	device_sysctl_init(dev);
2981 	if (!device_is_quiet(dev))
2982 		device_print_child(dev->parent, dev);
2983 	attachtime = get_cyclecount();
2984 	dev->state = DS_ATTACHING;
2985 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2986 		printf("device_attach: %s%d attach returned %d\n",
2987 		    dev->driver->name, dev->unit, error);
2988 		if (!(dev->flags & DF_FIXEDCLASS))
2989 			devclass_delete_device(dev->devclass, dev);
2990 		(void)device_set_driver(dev, NULL);
2991 		device_sysctl_fini(dev);
2992 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2993 		dev->state = DS_NOTPRESENT;
2994 		return (error);
2995 	}
2996 	dev->flags |= DF_ATTACHED_ONCE;
2997 	/* We only need the low bits of this time, but ranges from tens to thousands
2998 	 * have been seen, so keep 2 bytes' worth.
2999 	 */
3000 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3001 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3002 	device_sysctl_update(dev);
3003 	dev->state = DS_ATTACHED;
3004 	dev->flags &= ~DF_DONENOMATCH;
3005 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3006 	devadded(dev);
3007 	return (0);
3008 }
3009 
3010 /**
3011  * @brief Detach a driver from a device
3012  *
3013  * This function is a wrapper around the DEVICE_DETACH() driver
3014  * method. If the call to DEVICE_DETACH() succeeds, it calls
3015  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3016  * notification event for user-based device management services and
3017  * cleans up the device's sysctl tree.
3018  *
3019  * @param dev		the device to un-initialise
3020  *
3021  * @retval 0		success
3022  * @retval ENXIO	no driver was found
3023  * @retval ENOMEM	memory allocation failure
3024  * @retval non-zero	some other unix error code
3025  */
3026 int
3027 device_detach(device_t dev)
3028 {
3029 	int error;
3030 
3031 	GIANT_REQUIRED;
3032 
3033 	PDEBUG(("%s", DEVICENAME(dev)));
3034 	if (dev->busy > 0)
3035 		return (EBUSY);
3036 	if (dev->state == DS_ATTACHING) {
3037 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3038 		return (EBUSY);
3039 	}
3040 	if (dev->state != DS_ATTACHED)
3041 		return (0);
3042 
3043 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3044 	if ((error = DEVICE_DETACH(dev)) != 0) {
3045 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3046 		    EVHDEV_DETACH_FAILED);
3047 		return (error);
3048 	} else {
3049 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3050 		    EVHDEV_DETACH_COMPLETE);
3051 	}
3052 	devremoved(dev);
3053 	if (!device_is_quiet(dev))
3054 		device_printf(dev, "detached\n");
3055 	if (dev->parent)
3056 		BUS_CHILD_DETACHED(dev->parent, dev);
3057 
3058 	if (!(dev->flags & DF_FIXEDCLASS))
3059 		devclass_delete_device(dev->devclass, dev);
3060 
3061 	device_verbose(dev);
3062 	dev->state = DS_NOTPRESENT;
3063 	(void)device_set_driver(dev, NULL);
3064 	device_sysctl_fini(dev);
3065 
3066 	return (0);
3067 }
3068 
3069 /**
3070  * @brief Tells a driver to quiesce itself.
3071  *
3072  * This function is a wrapper around the DEVICE_QUIESCE() driver
3073  * method. If the call to DEVICE_QUIESCE() succeeds.
3074  *
3075  * @param dev		the device to quiesce
3076  *
3077  * @retval 0		success
3078  * @retval ENXIO	no driver was found
3079  * @retval ENOMEM	memory allocation failure
3080  * @retval non-zero	some other unix error code
3081  */
3082 int
3083 device_quiesce(device_t dev)
3084 {
3085 	PDEBUG(("%s", DEVICENAME(dev)));
3086 	if (dev->busy > 0)
3087 		return (EBUSY);
3088 	if (dev->state != DS_ATTACHED)
3089 		return (0);
3090 
3091 	return (DEVICE_QUIESCE(dev));
3092 }
3093 
3094 /**
3095  * @brief Notify a device of system shutdown
3096  *
3097  * This function calls the DEVICE_SHUTDOWN() driver method if the
3098  * device currently has an attached driver.
3099  *
3100  * @returns the value returned by DEVICE_SHUTDOWN()
3101  */
3102 int
3103 device_shutdown(device_t dev)
3104 {
3105 	if (dev->state < DS_ATTACHED)
3106 		return (0);
3107 	return (DEVICE_SHUTDOWN(dev));
3108 }
3109 
3110 /**
3111  * @brief Set the unit number of a device
3112  *
3113  * This function can be used to override the unit number used for a
3114  * device (e.g. to wire a device to a pre-configured unit number).
3115  */
3116 int
3117 device_set_unit(device_t dev, int unit)
3118 {
3119 	devclass_t dc;
3120 	int err;
3121 
3122 	if (unit == dev->unit)
3123 		return (0);
3124 	dc = device_get_devclass(dev);
3125 	if (unit < dc->maxunit && dc->devices[unit])
3126 		return (EBUSY);
3127 	err = devclass_delete_device(dc, dev);
3128 	if (err)
3129 		return (err);
3130 	dev->unit = unit;
3131 	err = devclass_add_device(dc, dev);
3132 	if (err)
3133 		return (err);
3134 
3135 	bus_data_generation_update();
3136 	return (0);
3137 }
3138 
3139 /*======================================*/
3140 /*
3141  * Some useful method implementations to make life easier for bus drivers.
3142  */
3143 
3144 void
3145 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3146 {
3147 	bzero(args, sz);
3148 	args->size = sz;
3149 	args->memattr = VM_MEMATTR_DEVICE;
3150 }
3151 
3152 /**
3153  * @brief Initialise a resource list.
3154  *
3155  * @param rl		the resource list to initialise
3156  */
3157 void
3158 resource_list_init(struct resource_list *rl)
3159 {
3160 	STAILQ_INIT(rl);
3161 }
3162 
3163 /**
3164  * @brief Reclaim memory used by a resource list.
3165  *
3166  * This function frees the memory for all resource entries on the list
3167  * (if any).
3168  *
3169  * @param rl		the resource list to free
3170  */
3171 void
3172 resource_list_free(struct resource_list *rl)
3173 {
3174 	struct resource_list_entry *rle;
3175 
3176 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3177 		if (rle->res)
3178 			panic("resource_list_free: resource entry is busy");
3179 		STAILQ_REMOVE_HEAD(rl, link);
3180 		free(rle, M_BUS);
3181 	}
3182 }
3183 
3184 /**
3185  * @brief Add a resource entry.
3186  *
3187  * This function adds a resource entry using the given @p type, @p
3188  * start, @p end and @p count values. A rid value is chosen by
3189  * searching sequentially for the first unused rid starting at zero.
3190  *
3191  * @param rl		the resource list to edit
3192  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3193  * @param start		the start address of the resource
3194  * @param end		the end address of the resource
3195  * @param count		XXX end-start+1
3196  */
3197 int
3198 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3199     rman_res_t end, rman_res_t count)
3200 {
3201 	int rid;
3202 
3203 	rid = 0;
3204 	while (resource_list_find(rl, type, rid) != NULL)
3205 		rid++;
3206 	resource_list_add(rl, type, rid, start, end, count);
3207 	return (rid);
3208 }
3209 
3210 /**
3211  * @brief Add or modify a resource entry.
3212  *
3213  * If an existing entry exists with the same type and rid, it will be
3214  * modified using the given values of @p start, @p end and @p
3215  * count. If no entry exists, a new one will be created using the
3216  * given values.  The resource list entry that matches is then returned.
3217  *
3218  * @param rl		the resource list to edit
3219  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3220  * @param rid		the resource identifier
3221  * @param start		the start address of the resource
3222  * @param end		the end address of the resource
3223  * @param count		XXX end-start+1
3224  */
3225 struct resource_list_entry *
3226 resource_list_add(struct resource_list *rl, int type, int rid,
3227     rman_res_t start, rman_res_t end, rman_res_t count)
3228 {
3229 	struct resource_list_entry *rle;
3230 
3231 	rle = resource_list_find(rl, type, rid);
3232 	if (!rle) {
3233 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3234 		    M_NOWAIT);
3235 		if (!rle)
3236 			panic("resource_list_add: can't record entry");
3237 		STAILQ_INSERT_TAIL(rl, rle, link);
3238 		rle->type = type;
3239 		rle->rid = rid;
3240 		rle->res = NULL;
3241 		rle->flags = 0;
3242 	}
3243 
3244 	if (rle->res)
3245 		panic("resource_list_add: resource entry is busy");
3246 
3247 	rle->start = start;
3248 	rle->end = end;
3249 	rle->count = count;
3250 	return (rle);
3251 }
3252 
3253 /**
3254  * @brief Determine if a resource entry is busy.
3255  *
3256  * Returns true if a resource entry is busy meaning that it has an
3257  * associated resource that is not an unallocated "reserved" resource.
3258  *
3259  * @param rl		the resource list to search
3260  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3261  * @param rid		the resource identifier
3262  *
3263  * @returns Non-zero if the entry is busy, zero otherwise.
3264  */
3265 int
3266 resource_list_busy(struct resource_list *rl, int type, int rid)
3267 {
3268 	struct resource_list_entry *rle;
3269 
3270 	rle = resource_list_find(rl, type, rid);
3271 	if (rle == NULL || rle->res == NULL)
3272 		return (0);
3273 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3274 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3275 		    ("reserved resource is active"));
3276 		return (0);
3277 	}
3278 	return (1);
3279 }
3280 
3281 /**
3282  * @brief Determine if a resource entry is reserved.
3283  *
3284  * Returns true if a resource entry is reserved meaning that it has an
3285  * associated "reserved" resource.  The resource can either be
3286  * allocated or unallocated.
3287  *
3288  * @param rl		the resource list to search
3289  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3290  * @param rid		the resource identifier
3291  *
3292  * @returns Non-zero if the entry is reserved, zero otherwise.
3293  */
3294 int
3295 resource_list_reserved(struct resource_list *rl, int type, int rid)
3296 {
3297 	struct resource_list_entry *rle;
3298 
3299 	rle = resource_list_find(rl, type, rid);
3300 	if (rle != NULL && rle->flags & RLE_RESERVED)
3301 		return (1);
3302 	return (0);
3303 }
3304 
3305 /**
3306  * @brief Find a resource entry by type and rid.
3307  *
3308  * @param rl		the resource list to search
3309  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3310  * @param rid		the resource identifier
3311  *
3312  * @returns the resource entry pointer or NULL if there is no such
3313  * entry.
3314  */
3315 struct resource_list_entry *
3316 resource_list_find(struct resource_list *rl, int type, int rid)
3317 {
3318 	struct resource_list_entry *rle;
3319 
3320 	STAILQ_FOREACH(rle, rl, link) {
3321 		if (rle->type == type && rle->rid == rid)
3322 			return (rle);
3323 	}
3324 	return (NULL);
3325 }
3326 
3327 /**
3328  * @brief Delete a resource entry.
3329  *
3330  * @param rl		the resource list to edit
3331  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3332  * @param rid		the resource identifier
3333  */
3334 void
3335 resource_list_delete(struct resource_list *rl, int type, int rid)
3336 {
3337 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3338 
3339 	if (rle) {
3340 		if (rle->res != NULL)
3341 			panic("resource_list_delete: resource has not been released");
3342 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3343 		free(rle, M_BUS);
3344 	}
3345 }
3346 
3347 /**
3348  * @brief Allocate a reserved resource
3349  *
3350  * This can be used by buses to force the allocation of resources
3351  * that are always active in the system even if they are not allocated
3352  * by a driver (e.g. PCI BARs).  This function is usually called when
3353  * adding a new child to the bus.  The resource is allocated from the
3354  * parent bus when it is reserved.  The resource list entry is marked
3355  * with RLE_RESERVED to note that it is a reserved resource.
3356  *
3357  * Subsequent attempts to allocate the resource with
3358  * resource_list_alloc() will succeed the first time and will set
3359  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3360  * resource that has been allocated is released with
3361  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3362  * the actual resource remains allocated.  The resource can be released to
3363  * the parent bus by calling resource_list_unreserve().
3364  *
3365  * @param rl		the resource list to allocate from
3366  * @param bus		the parent device of @p child
3367  * @param child		the device for which the resource is being reserved
3368  * @param type		the type of resource to allocate
3369  * @param rid		a pointer to the resource identifier
3370  * @param start		hint at the start of the resource range - pass
3371  *			@c 0 for any start address
3372  * @param end		hint at the end of the resource range - pass
3373  *			@c ~0 for any end address
3374  * @param count		hint at the size of range required - pass @c 1
3375  *			for any size
3376  * @param flags		any extra flags to control the resource
3377  *			allocation - see @c RF_XXX flags in
3378  *			<sys/rman.h> for details
3379  *
3380  * @returns		the resource which was allocated or @c NULL if no
3381  *			resource could be allocated
3382  */
3383 struct resource *
3384 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3385     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3386 {
3387 	struct resource_list_entry *rle = NULL;
3388 	int passthrough = (device_get_parent(child) != bus);
3389 	struct resource *r;
3390 
3391 	if (passthrough)
3392 		panic(
3393     "resource_list_reserve() should only be called for direct children");
3394 	if (flags & RF_ACTIVE)
3395 		panic(
3396     "resource_list_reserve() should only reserve inactive resources");
3397 
3398 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3399 	    flags);
3400 	if (r != NULL) {
3401 		rle = resource_list_find(rl, type, *rid);
3402 		rle->flags |= RLE_RESERVED;
3403 	}
3404 	return (r);
3405 }
3406 
3407 /**
3408  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3409  *
3410  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3411  * and passing the allocation up to the parent of @p bus. This assumes
3412  * that the first entry of @c device_get_ivars(child) is a struct
3413  * resource_list. This also handles 'passthrough' allocations where a
3414  * child is a remote descendant of bus by passing the allocation up to
3415  * the parent of bus.
3416  *
3417  * Typically, a bus driver would store a list of child resources
3418  * somewhere in the child device's ivars (see device_get_ivars()) and
3419  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3420  * then call resource_list_alloc() to perform the allocation.
3421  *
3422  * @param rl		the resource list to allocate from
3423  * @param bus		the parent device of @p child
3424  * @param child		the device which is requesting an allocation
3425  * @param type		the type of resource to allocate
3426  * @param rid		a pointer to the resource identifier
3427  * @param start		hint at the start of the resource range - pass
3428  *			@c 0 for any start address
3429  * @param end		hint at the end of the resource range - pass
3430  *			@c ~0 for any end address
3431  * @param count		hint at the size of range required - pass @c 1
3432  *			for any size
3433  * @param flags		any extra flags to control the resource
3434  *			allocation - see @c RF_XXX flags in
3435  *			<sys/rman.h> for details
3436  *
3437  * @returns		the resource which was allocated or @c NULL if no
3438  *			resource could be allocated
3439  */
3440 struct resource *
3441 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3442     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3443 {
3444 	struct resource_list_entry *rle = NULL;
3445 	int passthrough = (device_get_parent(child) != bus);
3446 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3447 
3448 	if (passthrough) {
3449 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3450 		    type, rid, start, end, count, flags));
3451 	}
3452 
3453 	rle = resource_list_find(rl, type, *rid);
3454 
3455 	if (!rle)
3456 		return (NULL);		/* no resource of that type/rid */
3457 
3458 	if (rle->res) {
3459 		if (rle->flags & RLE_RESERVED) {
3460 			if (rle->flags & RLE_ALLOCATED)
3461 				return (NULL);
3462 			if ((flags & RF_ACTIVE) &&
3463 			    bus_activate_resource(child, type, *rid,
3464 			    rle->res) != 0)
3465 				return (NULL);
3466 			rle->flags |= RLE_ALLOCATED;
3467 			return (rle->res);
3468 		}
3469 		device_printf(bus,
3470 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3471 		    type, device_get_nameunit(child));
3472 		return (NULL);
3473 	}
3474 
3475 	if (isdefault) {
3476 		start = rle->start;
3477 		count = ulmax(count, rle->count);
3478 		end = ulmax(rle->end, start + count - 1);
3479 	}
3480 
3481 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3482 	    type, rid, start, end, count, flags);
3483 
3484 	/*
3485 	 * Record the new range.
3486 	 */
3487 	if (rle->res) {
3488 		rle->start = rman_get_start(rle->res);
3489 		rle->end = rman_get_end(rle->res);
3490 		rle->count = count;
3491 	}
3492 
3493 	return (rle->res);
3494 }
3495 
3496 /**
3497  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3498  *
3499  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3500  * used with resource_list_alloc().
3501  *
3502  * @param rl		the resource list which was allocated from
3503  * @param bus		the parent device of @p child
3504  * @param child		the device which is requesting a release
3505  * @param type		the type of resource to release
3506  * @param rid		the resource identifier
3507  * @param res		the resource to release
3508  *
3509  * @retval 0		success
3510  * @retval non-zero	a standard unix error code indicating what
3511  *			error condition prevented the operation
3512  */
3513 int
3514 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3515     int type, int rid, struct resource *res)
3516 {
3517 	struct resource_list_entry *rle = NULL;
3518 	int passthrough = (device_get_parent(child) != bus);
3519 	int error;
3520 
3521 	if (passthrough) {
3522 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3523 		    type, rid, res));
3524 	}
3525 
3526 	rle = resource_list_find(rl, type, rid);
3527 
3528 	if (!rle)
3529 		panic("resource_list_release: can't find resource");
3530 	if (!rle->res)
3531 		panic("resource_list_release: resource entry is not busy");
3532 	if (rle->flags & RLE_RESERVED) {
3533 		if (rle->flags & RLE_ALLOCATED) {
3534 			if (rman_get_flags(res) & RF_ACTIVE) {
3535 				error = bus_deactivate_resource(child, type,
3536 				    rid, res);
3537 				if (error)
3538 					return (error);
3539 			}
3540 			rle->flags &= ~RLE_ALLOCATED;
3541 			return (0);
3542 		}
3543 		return (EINVAL);
3544 	}
3545 
3546 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3547 	    type, rid, res);
3548 	if (error)
3549 		return (error);
3550 
3551 	rle->res = NULL;
3552 	return (0);
3553 }
3554 
3555 /**
3556  * @brief Release all active resources of a given type
3557  *
3558  * Release all active resources of a specified type.  This is intended
3559  * to be used to cleanup resources leaked by a driver after detach or
3560  * a failed attach.
3561  *
3562  * @param rl		the resource list which was allocated from
3563  * @param bus		the parent device of @p child
3564  * @param child		the device whose active resources are being released
3565  * @param type		the type of resources to release
3566  *
3567  * @retval 0		success
3568  * @retval EBUSY	at least one resource was active
3569  */
3570 int
3571 resource_list_release_active(struct resource_list *rl, device_t bus,
3572     device_t child, int type)
3573 {
3574 	struct resource_list_entry *rle;
3575 	int error, retval;
3576 
3577 	retval = 0;
3578 	STAILQ_FOREACH(rle, rl, link) {
3579 		if (rle->type != type)
3580 			continue;
3581 		if (rle->res == NULL)
3582 			continue;
3583 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3584 		    RLE_RESERVED)
3585 			continue;
3586 		retval = EBUSY;
3587 		error = resource_list_release(rl, bus, child, type,
3588 		    rman_get_rid(rle->res), rle->res);
3589 		if (error != 0)
3590 			device_printf(bus,
3591 			    "Failed to release active resource: %d\n", error);
3592 	}
3593 	return (retval);
3594 }
3595 
3596 /**
3597  * @brief Fully release a reserved resource
3598  *
3599  * Fully releases a resource reserved via resource_list_reserve().
3600  *
3601  * @param rl		the resource list which was allocated from
3602  * @param bus		the parent device of @p child
3603  * @param child		the device whose reserved resource is being released
3604  * @param type		the type of resource to release
3605  * @param rid		the resource identifier
3606  * @param res		the resource to release
3607  *
3608  * @retval 0		success
3609  * @retval non-zero	a standard unix error code indicating what
3610  *			error condition prevented the operation
3611  */
3612 int
3613 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3614     int type, int rid)
3615 {
3616 	struct resource_list_entry *rle = NULL;
3617 	int passthrough = (device_get_parent(child) != bus);
3618 
3619 	if (passthrough)
3620 		panic(
3621     "resource_list_unreserve() should only be called for direct children");
3622 
3623 	rle = resource_list_find(rl, type, rid);
3624 
3625 	if (!rle)
3626 		panic("resource_list_unreserve: can't find resource");
3627 	if (!(rle->flags & RLE_RESERVED))
3628 		return (EINVAL);
3629 	if (rle->flags & RLE_ALLOCATED)
3630 		return (EBUSY);
3631 	rle->flags &= ~RLE_RESERVED;
3632 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3633 }
3634 
3635 /**
3636  * @brief Print a description of resources in a resource list
3637  *
3638  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3639  * The name is printed if at least one resource of the given type is available.
3640  * The format is used to print resource start and end.
3641  *
3642  * @param rl		the resource list to print
3643  * @param name		the name of @p type, e.g. @c "memory"
3644  * @param type		type type of resource entry to print
3645  * @param format	printf(9) format string to print resource
3646  *			start and end values
3647  *
3648  * @returns		the number of characters printed
3649  */
3650 int
3651 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3652     const char *format)
3653 {
3654 	struct resource_list_entry *rle;
3655 	int printed, retval;
3656 
3657 	printed = 0;
3658 	retval = 0;
3659 	/* Yes, this is kinda cheating */
3660 	STAILQ_FOREACH(rle, rl, link) {
3661 		if (rle->type == type) {
3662 			if (printed == 0)
3663 				retval += printf(" %s ", name);
3664 			else
3665 				retval += printf(",");
3666 			printed++;
3667 			retval += printf(format, rle->start);
3668 			if (rle->count > 1) {
3669 				retval += printf("-");
3670 				retval += printf(format, rle->start +
3671 						 rle->count - 1);
3672 			}
3673 		}
3674 	}
3675 	return (retval);
3676 }
3677 
3678 /**
3679  * @brief Releases all the resources in a list.
3680  *
3681  * @param rl		The resource list to purge.
3682  *
3683  * @returns		nothing
3684  */
3685 void
3686 resource_list_purge(struct resource_list *rl)
3687 {
3688 	struct resource_list_entry *rle;
3689 
3690 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3691 		if (rle->res)
3692 			bus_release_resource(rman_get_device(rle->res),
3693 			    rle->type, rle->rid, rle->res);
3694 		STAILQ_REMOVE_HEAD(rl, link);
3695 		free(rle, M_BUS);
3696 	}
3697 }
3698 
3699 device_t
3700 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
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 	DEVICE_RESUME(child);
3850 	child->flags &= ~DF_SUSPENDED;
3851 
3852 	return (0);
3853 }
3854 
3855 /**
3856  * @brief Helper function for implementing DEVICE_SUSPEND()
3857  *
3858  * This function can be used to help implement the DEVICE_SUSPEND()
3859  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3860  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3861  * operation is aborted and any devices which were suspended are
3862  * resumed immediately by calling their DEVICE_RESUME() methods.
3863  */
3864 int
3865 bus_generic_suspend(device_t dev)
3866 {
3867 	int		error;
3868 	device_t	child;
3869 
3870 	/*
3871 	 * Suspend children in the reverse order.
3872 	 * For most buses all children are equal, so the order does not matter.
3873 	 * Other buses, such as acpi, carefully order their child devices to
3874 	 * express implicit dependencies between them.  For such buses it is
3875 	 * safer to bring down devices in the reverse order.
3876 	 */
3877 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3878 		error = BUS_SUSPEND_CHILD(dev, child);
3879 		if (error != 0) {
3880 			child = TAILQ_NEXT(child, link);
3881 			if (child != NULL) {
3882 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3883 					BUS_RESUME_CHILD(dev, child);
3884 			}
3885 			return (error);
3886 		}
3887 	}
3888 	return (0);
3889 }
3890 
3891 /**
3892  * @brief Helper function for implementing DEVICE_RESUME()
3893  *
3894  * This function can be used to help implement the DEVICE_RESUME() for
3895  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3896  */
3897 int
3898 bus_generic_resume(device_t dev)
3899 {
3900 	device_t	child;
3901 
3902 	TAILQ_FOREACH(child, &dev->children, link) {
3903 		BUS_RESUME_CHILD(dev, child);
3904 		/* if resume fails, there's nothing we can usefully do... */
3905 	}
3906 	return (0);
3907 }
3908 
3909 /**
3910  * @brief Helper function for implementing BUS_RESET_POST
3911  *
3912  * Bus can use this function to implement common operations of
3913  * re-attaching or resuming the children after the bus itself was
3914  * reset, and after restoring bus-unique state of children.
3915  *
3916  * @param dev	The bus
3917  * #param flags	DEVF_RESET_*
3918  */
3919 int
3920 bus_helper_reset_post(device_t dev, int flags)
3921 {
3922 	device_t child;
3923 	int error, error1;
3924 
3925 	error = 0;
3926 	TAILQ_FOREACH(child, &dev->children,link) {
3927 		BUS_RESET_POST(dev, child);
3928 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3929 		    device_probe_and_attach(child) :
3930 		    BUS_RESUME_CHILD(dev, child);
3931 		if (error == 0 && error1 != 0)
3932 			error = error1;
3933 	}
3934 	return (error);
3935 }
3936 
3937 static void
3938 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3939 {
3940 	child = TAILQ_NEXT(child, link);
3941 	if (child == NULL)
3942 		return;
3943 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3944 		BUS_RESET_POST(dev, child);
3945 		if ((flags & DEVF_RESET_DETACH) != 0)
3946 			device_probe_and_attach(child);
3947 		else
3948 			BUS_RESUME_CHILD(dev, child);
3949 	}
3950 }
3951 
3952 /**
3953  * @brief Helper function for implementing BUS_RESET_PREPARE
3954  *
3955  * Bus can use this function to implement common operations of
3956  * detaching or suspending the children before the bus itself is
3957  * reset, and then save bus-unique state of children that must
3958  * persists around reset.
3959  *
3960  * @param dev	The bus
3961  * #param flags	DEVF_RESET_*
3962  */
3963 int
3964 bus_helper_reset_prepare(device_t dev, int flags)
3965 {
3966 	device_t child;
3967 	int error;
3968 
3969 	if (dev->state != DS_ATTACHED)
3970 		return (EBUSY);
3971 
3972 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3973 		if ((flags & DEVF_RESET_DETACH) != 0) {
3974 			error = device_get_state(child) == DS_ATTACHED ?
3975 			    device_detach(child) : 0;
3976 		} else {
3977 			error = BUS_SUSPEND_CHILD(dev, child);
3978 		}
3979 		if (error == 0) {
3980 			error = BUS_RESET_PREPARE(dev, child);
3981 			if (error != 0) {
3982 				if ((flags & DEVF_RESET_DETACH) != 0)
3983 					device_probe_and_attach(child);
3984 				else
3985 					BUS_RESUME_CHILD(dev, child);
3986 			}
3987 		}
3988 		if (error != 0) {
3989 			bus_helper_reset_prepare_rollback(dev, child, flags);
3990 			return (error);
3991 		}
3992 	}
3993 	return (0);
3994 }
3995 
3996 /**
3997  * @brief Helper function for implementing BUS_PRINT_CHILD().
3998  *
3999  * This function prints the first part of the ascii representation of
4000  * @p child, including its name, unit and description (if any - see
4001  * device_set_desc()).
4002  *
4003  * @returns the number of characters printed
4004  */
4005 int
4006 bus_print_child_header(device_t dev, device_t child)
4007 {
4008 	int	retval = 0;
4009 
4010 	if (device_get_desc(child)) {
4011 		retval += device_printf(child, "<%s>", device_get_desc(child));
4012 	} else {
4013 		retval += printf("%s", device_get_nameunit(child));
4014 	}
4015 
4016 	return (retval);
4017 }
4018 
4019 /**
4020  * @brief Helper function for implementing BUS_PRINT_CHILD().
4021  *
4022  * This function prints the last part of the ascii representation of
4023  * @p child, which consists of the string @c " on " followed by the
4024  * name and unit of the @p dev.
4025  *
4026  * @returns the number of characters printed
4027  */
4028 int
4029 bus_print_child_footer(device_t dev, device_t child)
4030 {
4031 	return (printf(" on %s\n", device_get_nameunit(dev)));
4032 }
4033 
4034 /**
4035  * @brief Helper function for implementing BUS_PRINT_CHILD().
4036  *
4037  * This function prints out the VM domain for the given device.
4038  *
4039  * @returns the number of characters printed
4040  */
4041 int
4042 bus_print_child_domain(device_t dev, device_t child)
4043 {
4044 	int domain;
4045 
4046 	/* No domain? Don't print anything */
4047 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4048 		return (0);
4049 
4050 	return (printf(" numa-domain %d", domain));
4051 }
4052 
4053 /**
4054  * @brief Helper function for implementing BUS_PRINT_CHILD().
4055  *
4056  * This function simply calls bus_print_child_header() followed by
4057  * bus_print_child_footer().
4058  *
4059  * @returns the number of characters printed
4060  */
4061 int
4062 bus_generic_print_child(device_t dev, device_t child)
4063 {
4064 	int	retval = 0;
4065 
4066 	retval += bus_print_child_header(dev, child);
4067 	retval += bus_print_child_domain(dev, child);
4068 	retval += bus_print_child_footer(dev, child);
4069 
4070 	return (retval);
4071 }
4072 
4073 /**
4074  * @brief Stub function for implementing BUS_READ_IVAR().
4075  *
4076  * @returns ENOENT
4077  */
4078 int
4079 bus_generic_read_ivar(device_t dev, device_t child, int index,
4080     uintptr_t * result)
4081 {
4082 	return (ENOENT);
4083 }
4084 
4085 /**
4086  * @brief Stub function for implementing BUS_WRITE_IVAR().
4087  *
4088  * @returns ENOENT
4089  */
4090 int
4091 bus_generic_write_ivar(device_t dev, device_t child, int index,
4092     uintptr_t value)
4093 {
4094 	return (ENOENT);
4095 }
4096 
4097 /**
4098  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4099  *
4100  * @returns NULL
4101  */
4102 struct resource_list *
4103 bus_generic_get_resource_list(device_t dev, device_t child)
4104 {
4105 	return (NULL);
4106 }
4107 
4108 /**
4109  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4110  *
4111  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4112  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4113  * and then calls device_probe_and_attach() for each unattached child.
4114  */
4115 void
4116 bus_generic_driver_added(device_t dev, driver_t *driver)
4117 {
4118 	device_t child;
4119 
4120 	DEVICE_IDENTIFY(driver, dev);
4121 	TAILQ_FOREACH(child, &dev->children, link) {
4122 		if (child->state == DS_NOTPRESENT)
4123 			device_probe_and_attach(child);
4124 	}
4125 }
4126 
4127 /**
4128  * @brief Helper function for implementing BUS_NEW_PASS().
4129  *
4130  * This implementing of BUS_NEW_PASS() first calls the identify
4131  * routines for any drivers that probe at the current pass.  Then it
4132  * walks the list of devices for this bus.  If a device is already
4133  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4134  * device is not already attached, it attempts to attach a driver to
4135  * it.
4136  */
4137 void
4138 bus_generic_new_pass(device_t dev)
4139 {
4140 	driverlink_t dl;
4141 	devclass_t dc;
4142 	device_t child;
4143 
4144 	dc = dev->devclass;
4145 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4146 		if (dl->pass == bus_current_pass)
4147 			DEVICE_IDENTIFY(dl->driver, dev);
4148 	}
4149 	TAILQ_FOREACH(child, &dev->children, link) {
4150 		if (child->state >= DS_ATTACHED)
4151 			BUS_NEW_PASS(child);
4152 		else if (child->state == DS_NOTPRESENT)
4153 			device_probe_and_attach(child);
4154 	}
4155 }
4156 
4157 /**
4158  * @brief Helper function for implementing BUS_SETUP_INTR().
4159  *
4160  * This simple implementation of BUS_SETUP_INTR() simply calls the
4161  * BUS_SETUP_INTR() method of the parent of @p dev.
4162  */
4163 int
4164 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4165     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4166     void **cookiep)
4167 {
4168 	/* Propagate up the bus hierarchy until someone handles it. */
4169 	if (dev->parent)
4170 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4171 		    filter, intr, arg, cookiep));
4172 	return (EINVAL);
4173 }
4174 
4175 /**
4176  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4177  *
4178  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4179  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4180  */
4181 int
4182 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4183     void *cookie)
4184 {
4185 	/* Propagate up the bus hierarchy until someone handles it. */
4186 	if (dev->parent)
4187 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4188 	return (EINVAL);
4189 }
4190 
4191 /**
4192  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4193  *
4194  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4195  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4196  */
4197 int
4198 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4199 {
4200 	/* Propagate up the bus hierarchy until someone handles it. */
4201 	if (dev->parent)
4202 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4203 	return (EINVAL);
4204 }
4205 
4206 /**
4207  * @brief Helper function for implementing BUS_RESUME_INTR().
4208  *
4209  * This simple implementation of BUS_RESUME_INTR() simply calls the
4210  * BUS_RESUME_INTR() method of the parent of @p dev.
4211  */
4212 int
4213 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4214 {
4215 	/* Propagate up the bus hierarchy until someone handles it. */
4216 	if (dev->parent)
4217 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4218 	return (EINVAL);
4219 }
4220 
4221 /**
4222  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4223  *
4224  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4225  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4226  */
4227 int
4228 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4229     struct resource *r, rman_res_t start, rman_res_t end)
4230 {
4231 	/* Propagate up the bus hierarchy until someone handles it. */
4232 	if (dev->parent)
4233 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4234 		    end));
4235 	return (EINVAL);
4236 }
4237 
4238 /*
4239  * @brief Helper function for implementing BUS_TRANSLATE_RESOURCE().
4240  *
4241  * This simple implementation of BUS_TRANSLATE_RESOURCE() simply calls the
4242  * BUS_TRANSLATE_RESOURCE() method of the parent of @p dev.  If there is no
4243  * parent, no translation happens.
4244  */
4245 int
4246 bus_generic_translate_resource(device_t dev, int type, rman_res_t start,
4247     rman_res_t *newstart)
4248 {
4249 	if (dev->parent)
4250 		return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start,
4251 		    newstart));
4252 	*newstart = start;
4253 	return (0);
4254 }
4255 
4256 /**
4257  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4258  *
4259  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4260  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4261  */
4262 struct resource *
4263 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4264     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4265 {
4266 	/* Propagate up the bus hierarchy until someone handles it. */
4267 	if (dev->parent)
4268 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4269 		    start, end, count, flags));
4270 	return (NULL);
4271 }
4272 
4273 /**
4274  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4275  *
4276  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4277  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4278  */
4279 int
4280 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4281     struct resource *r)
4282 {
4283 	/* Propagate up the bus hierarchy until someone handles it. */
4284 	if (dev->parent)
4285 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4286 		    r));
4287 	return (EINVAL);
4288 }
4289 
4290 /**
4291  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4292  *
4293  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4294  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4295  */
4296 int
4297 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4298     struct resource *r)
4299 {
4300 	/* Propagate up the bus hierarchy until someone handles it. */
4301 	if (dev->parent)
4302 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4303 		    r));
4304 	return (EINVAL);
4305 }
4306 
4307 /**
4308  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4309  *
4310  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4311  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4312  */
4313 int
4314 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4315     int rid, struct resource *r)
4316 {
4317 	/* Propagate up the bus hierarchy until someone handles it. */
4318 	if (dev->parent)
4319 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4320 		    r));
4321 	return (EINVAL);
4322 }
4323 
4324 /**
4325  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4326  *
4327  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4328  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4329  */
4330 int
4331 bus_generic_map_resource(device_t dev, device_t child, int type,
4332     struct resource *r, struct resource_map_request *args,
4333     struct resource_map *map)
4334 {
4335 	/* Propagate up the bus hierarchy until someone handles it. */
4336 	if (dev->parent)
4337 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4338 		    map));
4339 	return (EINVAL);
4340 }
4341 
4342 /**
4343  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4344  *
4345  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4346  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4347  */
4348 int
4349 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4350     struct resource *r, struct resource_map *map)
4351 {
4352 	/* Propagate up the bus hierarchy until someone handles it. */
4353 	if (dev->parent)
4354 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4355 	return (EINVAL);
4356 }
4357 
4358 /**
4359  * @brief Helper function for implementing BUS_BIND_INTR().
4360  *
4361  * This simple implementation of BUS_BIND_INTR() simply calls the
4362  * BUS_BIND_INTR() method of the parent of @p dev.
4363  */
4364 int
4365 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4366     int cpu)
4367 {
4368 	/* Propagate up the bus hierarchy until someone handles it. */
4369 	if (dev->parent)
4370 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4371 	return (EINVAL);
4372 }
4373 
4374 /**
4375  * @brief Helper function for implementing BUS_CONFIG_INTR().
4376  *
4377  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4378  * BUS_CONFIG_INTR() method of the parent of @p dev.
4379  */
4380 int
4381 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4382     enum intr_polarity pol)
4383 {
4384 	/* Propagate up the bus hierarchy until someone handles it. */
4385 	if (dev->parent)
4386 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4387 	return (EINVAL);
4388 }
4389 
4390 /**
4391  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4392  *
4393  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4394  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4395  */
4396 int
4397 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4398     void *cookie, const char *descr)
4399 {
4400 	/* Propagate up the bus hierarchy until someone handles it. */
4401 	if (dev->parent)
4402 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4403 		    descr));
4404 	return (EINVAL);
4405 }
4406 
4407 /**
4408  * @brief Helper function for implementing BUS_GET_CPUS().
4409  *
4410  * This simple implementation of BUS_GET_CPUS() simply calls the
4411  * BUS_GET_CPUS() method of the parent of @p dev.
4412  */
4413 int
4414 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4415     size_t setsize, cpuset_t *cpuset)
4416 {
4417 	/* Propagate up the bus hierarchy until someone handles it. */
4418 	if (dev->parent != NULL)
4419 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4420 	return (EINVAL);
4421 }
4422 
4423 /**
4424  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4425  *
4426  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4427  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4428  */
4429 bus_dma_tag_t
4430 bus_generic_get_dma_tag(device_t dev, device_t child)
4431 {
4432 	/* Propagate up the bus hierarchy until someone handles it. */
4433 	if (dev->parent != NULL)
4434 		return (BUS_GET_DMA_TAG(dev->parent, child));
4435 	return (NULL);
4436 }
4437 
4438 /**
4439  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4440  *
4441  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4442  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4443  */
4444 bus_space_tag_t
4445 bus_generic_get_bus_tag(device_t dev, device_t child)
4446 {
4447 	/* Propagate up the bus hierarchy until someone handles it. */
4448 	if (dev->parent != NULL)
4449 		return (BUS_GET_BUS_TAG(dev->parent, child));
4450 	return ((bus_space_tag_t)0);
4451 }
4452 
4453 /**
4454  * @brief Helper function for implementing BUS_GET_RESOURCE().
4455  *
4456  * This implementation of BUS_GET_RESOURCE() uses the
4457  * resource_list_find() function to do most of the work. It calls
4458  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4459  * search.
4460  */
4461 int
4462 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4463     rman_res_t *startp, rman_res_t *countp)
4464 {
4465 	struct resource_list *		rl = NULL;
4466 	struct resource_list_entry *	rle = NULL;
4467 
4468 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4469 	if (!rl)
4470 		return (EINVAL);
4471 
4472 	rle = resource_list_find(rl, type, rid);
4473 	if (!rle)
4474 		return (ENOENT);
4475 
4476 	if (startp)
4477 		*startp = rle->start;
4478 	if (countp)
4479 		*countp = rle->count;
4480 
4481 	return (0);
4482 }
4483 
4484 /**
4485  * @brief Helper function for implementing BUS_SET_RESOURCE().
4486  *
4487  * This implementation of BUS_SET_RESOURCE() uses the
4488  * resource_list_add() function to do most of the work. It calls
4489  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4490  * edit.
4491  */
4492 int
4493 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4494     rman_res_t start, rman_res_t count)
4495 {
4496 	struct resource_list *		rl = NULL;
4497 
4498 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4499 	if (!rl)
4500 		return (EINVAL);
4501 
4502 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4503 
4504 	return (0);
4505 }
4506 
4507 /**
4508  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4509  *
4510  * This implementation of BUS_DELETE_RESOURCE() uses the
4511  * resource_list_delete() function to do most of the work. It calls
4512  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4513  * edit.
4514  */
4515 void
4516 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4517 {
4518 	struct resource_list *		rl = NULL;
4519 
4520 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4521 	if (!rl)
4522 		return;
4523 
4524 	resource_list_delete(rl, type, rid);
4525 
4526 	return;
4527 }
4528 
4529 /**
4530  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4531  *
4532  * This implementation of BUS_RELEASE_RESOURCE() uses the
4533  * resource_list_release() function to do most of the work. It calls
4534  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4535  */
4536 int
4537 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4538     int rid, struct resource *r)
4539 {
4540 	struct resource_list *		rl = NULL;
4541 
4542 	if (device_get_parent(child) != dev)
4543 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4544 		    type, rid, r));
4545 
4546 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4547 	if (!rl)
4548 		return (EINVAL);
4549 
4550 	return (resource_list_release(rl, dev, child, type, rid, r));
4551 }
4552 
4553 /**
4554  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4555  *
4556  * This implementation of BUS_ALLOC_RESOURCE() uses the
4557  * resource_list_alloc() function to do most of the work. It calls
4558  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4559  */
4560 struct resource *
4561 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4562     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4563 {
4564 	struct resource_list *		rl = NULL;
4565 
4566 	if (device_get_parent(child) != dev)
4567 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4568 		    type, rid, start, end, count, flags));
4569 
4570 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4571 	if (!rl)
4572 		return (NULL);
4573 
4574 	return (resource_list_alloc(rl, dev, child, type, rid,
4575 	    start, end, count, flags));
4576 }
4577 
4578 /**
4579  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4580  *
4581  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4582  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4583  */
4584 int
4585 bus_generic_child_present(device_t dev, device_t child)
4586 {
4587 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4588 }
4589 
4590 int
4591 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4592 {
4593 	if (dev->parent)
4594 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4595 
4596 	return (ENOENT);
4597 }
4598 
4599 /**
4600  * @brief Helper function for implementing BUS_RESCAN().
4601  *
4602  * This null implementation of BUS_RESCAN() always fails to indicate
4603  * the bus does not support rescanning.
4604  */
4605 int
4606 bus_null_rescan(device_t dev)
4607 {
4608 	return (ENXIO);
4609 }
4610 
4611 /*
4612  * Some convenience functions to make it easier for drivers to use the
4613  * resource-management functions.  All these really do is hide the
4614  * indirection through the parent's method table, making for slightly
4615  * less-wordy code.  In the future, it might make sense for this code
4616  * to maintain some sort of a list of resources allocated by each device.
4617  */
4618 
4619 int
4620 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4621     struct resource **res)
4622 {
4623 	int i;
4624 
4625 	for (i = 0; rs[i].type != -1; i++)
4626 		res[i] = NULL;
4627 	for (i = 0; rs[i].type != -1; i++) {
4628 		res[i] = bus_alloc_resource_any(dev,
4629 		    rs[i].type, &rs[i].rid, rs[i].flags);
4630 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4631 			bus_release_resources(dev, rs, res);
4632 			return (ENXIO);
4633 		}
4634 	}
4635 	return (0);
4636 }
4637 
4638 void
4639 bus_release_resources(device_t dev, const struct resource_spec *rs,
4640     struct resource **res)
4641 {
4642 	int i;
4643 
4644 	for (i = 0; rs[i].type != -1; i++)
4645 		if (res[i] != NULL) {
4646 			bus_release_resource(
4647 			    dev, rs[i].type, rs[i].rid, res[i]);
4648 			res[i] = NULL;
4649 		}
4650 }
4651 
4652 /**
4653  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4654  *
4655  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4656  * parent of @p dev.
4657  */
4658 struct resource *
4659 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4660     rman_res_t end, rman_res_t count, u_int flags)
4661 {
4662 	struct resource *res;
4663 
4664 	if (dev->parent == NULL)
4665 		return (NULL);
4666 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4667 	    count, flags);
4668 	return (res);
4669 }
4670 
4671 /**
4672  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4673  *
4674  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4675  * parent of @p dev.
4676  */
4677 int
4678 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4679     rman_res_t end)
4680 {
4681 	if (dev->parent == NULL)
4682 		return (EINVAL);
4683 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4684 }
4685 
4686 /**
4687  * @brief Wrapper function for BUS_TRANSLATE_RESOURCE().
4688  *
4689  * This function simply calls the BUS_TRANSLATE_RESOURCE() method of the
4690  * parent of @p dev.
4691  */
4692 int
4693 bus_translate_resource(device_t dev, int type, rman_res_t start,
4694     rman_res_t *newstart)
4695 {
4696 	if (dev->parent == NULL)
4697 		return (EINVAL);
4698 	return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start, newstart));
4699 }
4700 
4701 /**
4702  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4703  *
4704  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4705  * parent of @p dev.
4706  */
4707 int
4708 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4709 {
4710 	if (dev->parent == NULL)
4711 		return (EINVAL);
4712 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4713 }
4714 
4715 /**
4716  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4717  *
4718  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4719  * parent of @p dev.
4720  */
4721 int
4722 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4723 {
4724 	if (dev->parent == NULL)
4725 		return (EINVAL);
4726 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4727 }
4728 
4729 /**
4730  * @brief Wrapper function for BUS_MAP_RESOURCE().
4731  *
4732  * This function simply calls the BUS_MAP_RESOURCE() method of the
4733  * parent of @p dev.
4734  */
4735 int
4736 bus_map_resource(device_t dev, int type, struct resource *r,
4737     struct resource_map_request *args, struct resource_map *map)
4738 {
4739 	if (dev->parent == NULL)
4740 		return (EINVAL);
4741 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4742 }
4743 
4744 /**
4745  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4746  *
4747  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4748  * parent of @p dev.
4749  */
4750 int
4751 bus_unmap_resource(device_t dev, int type, struct resource *r,
4752     struct resource_map *map)
4753 {
4754 	if (dev->parent == NULL)
4755 		return (EINVAL);
4756 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4757 }
4758 
4759 /**
4760  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4761  *
4762  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4763  * parent of @p dev.
4764  */
4765 int
4766 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4767 {
4768 	int rv;
4769 
4770 	if (dev->parent == NULL)
4771 		return (EINVAL);
4772 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4773 	return (rv);
4774 }
4775 
4776 /**
4777  * @brief Wrapper function for BUS_SETUP_INTR().
4778  *
4779  * This function simply calls the BUS_SETUP_INTR() method of the
4780  * parent of @p dev.
4781  */
4782 int
4783 bus_setup_intr(device_t dev, struct resource *r, int flags,
4784     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4785 {
4786 	int error;
4787 
4788 	if (dev->parent == NULL)
4789 		return (EINVAL);
4790 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4791 	    arg, cookiep);
4792 	if (error != 0)
4793 		return (error);
4794 	if (handler != NULL && !(flags & INTR_MPSAFE))
4795 		device_printf(dev, "[GIANT-LOCKED]\n");
4796 	return (0);
4797 }
4798 
4799 /**
4800  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4801  *
4802  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4803  * parent of @p dev.
4804  */
4805 int
4806 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4807 {
4808 	if (dev->parent == NULL)
4809 		return (EINVAL);
4810 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4811 }
4812 
4813 /**
4814  * @brief Wrapper function for BUS_SUSPEND_INTR().
4815  *
4816  * This function simply calls the BUS_SUSPEND_INTR() method of the
4817  * parent of @p dev.
4818  */
4819 int
4820 bus_suspend_intr(device_t dev, struct resource *r)
4821 {
4822 	if (dev->parent == NULL)
4823 		return (EINVAL);
4824 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4825 }
4826 
4827 /**
4828  * @brief Wrapper function for BUS_RESUME_INTR().
4829  *
4830  * This function simply calls the BUS_RESUME_INTR() method of the
4831  * parent of @p dev.
4832  */
4833 int
4834 bus_resume_intr(device_t dev, struct resource *r)
4835 {
4836 	if (dev->parent == NULL)
4837 		return (EINVAL);
4838 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4839 }
4840 
4841 /**
4842  * @brief Wrapper function for BUS_BIND_INTR().
4843  *
4844  * This function simply calls the BUS_BIND_INTR() method of the
4845  * parent of @p dev.
4846  */
4847 int
4848 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4849 {
4850 	if (dev->parent == NULL)
4851 		return (EINVAL);
4852 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4853 }
4854 
4855 /**
4856  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4857  *
4858  * This function first formats the requested description into a
4859  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4860  * the parent of @p dev.
4861  */
4862 int
4863 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4864     const char *fmt, ...)
4865 {
4866 	va_list ap;
4867 	char descr[MAXCOMLEN + 1];
4868 
4869 	if (dev->parent == NULL)
4870 		return (EINVAL);
4871 	va_start(ap, fmt);
4872 	vsnprintf(descr, sizeof(descr), fmt, ap);
4873 	va_end(ap);
4874 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4875 }
4876 
4877 /**
4878  * @brief Wrapper function for BUS_SET_RESOURCE().
4879  *
4880  * This function simply calls the BUS_SET_RESOURCE() method of the
4881  * parent of @p dev.
4882  */
4883 int
4884 bus_set_resource(device_t dev, int type, int rid,
4885     rman_res_t start, rman_res_t count)
4886 {
4887 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4888 	    start, count));
4889 }
4890 
4891 /**
4892  * @brief Wrapper function for BUS_GET_RESOURCE().
4893  *
4894  * This function simply calls the BUS_GET_RESOURCE() method of the
4895  * parent of @p dev.
4896  */
4897 int
4898 bus_get_resource(device_t dev, int type, int rid,
4899     rman_res_t *startp, rman_res_t *countp)
4900 {
4901 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4902 	    startp, countp));
4903 }
4904 
4905 /**
4906  * @brief Wrapper function for BUS_GET_RESOURCE().
4907  *
4908  * This function simply calls the BUS_GET_RESOURCE() method of the
4909  * parent of @p dev and returns the start value.
4910  */
4911 rman_res_t
4912 bus_get_resource_start(device_t dev, int type, int rid)
4913 {
4914 	rman_res_t start;
4915 	rman_res_t count;
4916 	int error;
4917 
4918 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4919 	    &start, &count);
4920 	if (error)
4921 		return (0);
4922 	return (start);
4923 }
4924 
4925 /**
4926  * @brief Wrapper function for BUS_GET_RESOURCE().
4927  *
4928  * This function simply calls the BUS_GET_RESOURCE() method of the
4929  * parent of @p dev and returns the count value.
4930  */
4931 rman_res_t
4932 bus_get_resource_count(device_t dev, int type, int rid)
4933 {
4934 	rman_res_t start;
4935 	rman_res_t count;
4936 	int error;
4937 
4938 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4939 	    &start, &count);
4940 	if (error)
4941 		return (0);
4942 	return (count);
4943 }
4944 
4945 /**
4946  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4947  *
4948  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4949  * parent of @p dev.
4950  */
4951 void
4952 bus_delete_resource(device_t dev, int type, int rid)
4953 {
4954 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4955 }
4956 
4957 /**
4958  * @brief Wrapper function for BUS_CHILD_PRESENT().
4959  *
4960  * This function simply calls the BUS_CHILD_PRESENT() method of the
4961  * parent of @p dev.
4962  */
4963 int
4964 bus_child_present(device_t child)
4965 {
4966 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4967 }
4968 
4969 /**
4970  * @brief Wrapper function for BUS_CHILD_PNPINFO().
4971  *
4972  * This function simply calls the BUS_CHILD_PNPINFO() method of the parent of @p
4973  * dev.
4974  */
4975 int
4976 bus_child_pnpinfo(device_t child, struct sbuf *sb)
4977 {
4978 	device_t parent;
4979 
4980 	parent = device_get_parent(child);
4981 	if (parent == NULL)
4982 		return (0);
4983 	return (BUS_CHILD_PNPINFO(parent, child, sb));
4984 }
4985 
4986 /**
4987  * @brief Generic implementation that does nothing for bus_child_pnpinfo
4988  *
4989  * This function has the right signature and returns 0 since the sbuf is passed
4990  * to us to append to.
4991  */
4992 int
4993 bus_generic_child_pnpinfo(device_t dev, device_t child, struct sbuf *sb)
4994 {
4995 	return (0);
4996 }
4997 
4998 /**
4999  * @brief Wrapper function for BUS_CHILD_LOCATION().
5000  *
5001  * This function simply calls the BUS_CHILD_LOCATION() method of the parent of
5002  * @p dev.
5003  */
5004 int
5005 bus_child_location(device_t child, struct sbuf *sb)
5006 {
5007 	device_t parent;
5008 
5009 	parent = device_get_parent(child);
5010 	if (parent == NULL)
5011 		return (0);
5012 	return (BUS_CHILD_LOCATION(parent, child, sb));
5013 }
5014 
5015 /**
5016  * @brief Generic implementation that does nothing for bus_child_location
5017  *
5018  * This function has the right signature and returns 0 since the sbuf is passed
5019  * to us to append to.
5020  */
5021 int
5022 bus_generic_child_location(device_t dev, device_t child, struct sbuf *sb)
5023 {
5024 	return (0);
5025 }
5026 
5027 /**
5028  * @brief Wrapper function for BUS_GET_CPUS().
5029  *
5030  * This function simply calls the BUS_GET_CPUS() method of the
5031  * parent of @p dev.
5032  */
5033 int
5034 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5035 {
5036 	device_t parent;
5037 
5038 	parent = device_get_parent(dev);
5039 	if (parent == NULL)
5040 		return (EINVAL);
5041 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5042 }
5043 
5044 /**
5045  * @brief Wrapper function for BUS_GET_DMA_TAG().
5046  *
5047  * This function simply calls the BUS_GET_DMA_TAG() method of the
5048  * parent of @p dev.
5049  */
5050 bus_dma_tag_t
5051 bus_get_dma_tag(device_t dev)
5052 {
5053 	device_t parent;
5054 
5055 	parent = device_get_parent(dev);
5056 	if (parent == NULL)
5057 		return (NULL);
5058 	return (BUS_GET_DMA_TAG(parent, dev));
5059 }
5060 
5061 /**
5062  * @brief Wrapper function for BUS_GET_BUS_TAG().
5063  *
5064  * This function simply calls the BUS_GET_BUS_TAG() method of the
5065  * parent of @p dev.
5066  */
5067 bus_space_tag_t
5068 bus_get_bus_tag(device_t dev)
5069 {
5070 	device_t parent;
5071 
5072 	parent = device_get_parent(dev);
5073 	if (parent == NULL)
5074 		return ((bus_space_tag_t)0);
5075 	return (BUS_GET_BUS_TAG(parent, dev));
5076 }
5077 
5078 /**
5079  * @brief Wrapper function for BUS_GET_DOMAIN().
5080  *
5081  * This function simply calls the BUS_GET_DOMAIN() method of the
5082  * parent of @p dev.
5083  */
5084 int
5085 bus_get_domain(device_t dev, int *domain)
5086 {
5087 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5088 }
5089 
5090 /* Resume all devices and then notify userland that we're up again. */
5091 static int
5092 root_resume(device_t dev)
5093 {
5094 	int error;
5095 
5096 	error = bus_generic_resume(dev);
5097 	if (error == 0) {
5098 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5099 		devctl_notify("kernel", "power", "resume", NULL);
5100 	}
5101 	return (error);
5102 }
5103 
5104 static int
5105 root_print_child(device_t dev, device_t child)
5106 {
5107 	int	retval = 0;
5108 
5109 	retval += bus_print_child_header(dev, child);
5110 	retval += printf("\n");
5111 
5112 	return (retval);
5113 }
5114 
5115 static int
5116 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5117     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5118 {
5119 	/*
5120 	 * If an interrupt mapping gets to here something bad has happened.
5121 	 */
5122 	panic("root_setup_intr");
5123 }
5124 
5125 /*
5126  * If we get here, assume that the device is permanent and really is
5127  * present in the system.  Removable bus drivers are expected to intercept
5128  * this call long before it gets here.  We return -1 so that drivers that
5129  * really care can check vs -1 or some ERRNO returned higher in the food
5130  * chain.
5131  */
5132 static int
5133 root_child_present(device_t dev, device_t child)
5134 {
5135 	return (-1);
5136 }
5137 
5138 static int
5139 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5140     cpuset_t *cpuset)
5141 {
5142 	switch (op) {
5143 	case INTR_CPUS:
5144 		/* Default to returning the set of all CPUs. */
5145 		if (setsize != sizeof(cpuset_t))
5146 			return (EINVAL);
5147 		*cpuset = all_cpus;
5148 		return (0);
5149 	default:
5150 		return (EINVAL);
5151 	}
5152 }
5153 
5154 static kobj_method_t root_methods[] = {
5155 	/* Device interface */
5156 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5157 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5158 	KOBJMETHOD(device_resume,	root_resume),
5159 
5160 	/* Bus interface */
5161 	KOBJMETHOD(bus_print_child,	root_print_child),
5162 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5163 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5164 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5165 	KOBJMETHOD(bus_child_present,	root_child_present),
5166 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5167 
5168 	KOBJMETHOD_END
5169 };
5170 
5171 static driver_t root_driver = {
5172 	"root",
5173 	root_methods,
5174 	1,			/* no softc */
5175 };
5176 
5177 device_t	root_bus;
5178 devclass_t	root_devclass;
5179 
5180 static int
5181 root_bus_module_handler(module_t mod, int what, void* arg)
5182 {
5183 	switch (what) {
5184 	case MOD_LOAD:
5185 		TAILQ_INIT(&bus_data_devices);
5186 		kobj_class_compile((kobj_class_t) &root_driver);
5187 		root_bus = make_device(NULL, "root", 0);
5188 		root_bus->desc = "System root bus";
5189 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5190 		root_bus->driver = &root_driver;
5191 		root_bus->state = DS_ATTACHED;
5192 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5193 		devinit();
5194 		return (0);
5195 
5196 	case MOD_SHUTDOWN:
5197 		device_shutdown(root_bus);
5198 		return (0);
5199 	default:
5200 		return (EOPNOTSUPP);
5201 	}
5202 
5203 	return (0);
5204 }
5205 
5206 static moduledata_t root_bus_mod = {
5207 	"rootbus",
5208 	root_bus_module_handler,
5209 	NULL
5210 };
5211 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5212 
5213 /**
5214  * @brief Automatically configure devices
5215  *
5216  * This function begins the autoconfiguration process by calling
5217  * device_probe_and_attach() for each child of the @c root0 device.
5218  */
5219 void
5220 root_bus_configure(void)
5221 {
5222 	PDEBUG(("."));
5223 
5224 	/* Eventually this will be split up, but this is sufficient for now. */
5225 	bus_set_pass(BUS_PASS_DEFAULT);
5226 }
5227 
5228 /**
5229  * @brief Module handler for registering device drivers
5230  *
5231  * This module handler is used to automatically register device
5232  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5233  * devclass_add_driver() for the driver described by the
5234  * driver_module_data structure pointed to by @p arg
5235  */
5236 int
5237 driver_module_handler(module_t mod, int what, void *arg)
5238 {
5239 	struct driver_module_data *dmd;
5240 	devclass_t bus_devclass;
5241 	kobj_class_t driver;
5242 	int error, pass;
5243 
5244 	dmd = (struct driver_module_data *)arg;
5245 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5246 	error = 0;
5247 
5248 	switch (what) {
5249 	case MOD_LOAD:
5250 		if (dmd->dmd_chainevh)
5251 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5252 
5253 		pass = dmd->dmd_pass;
5254 		driver = dmd->dmd_driver;
5255 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5256 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5257 		error = devclass_add_driver(bus_devclass, driver, pass,
5258 		    dmd->dmd_devclass);
5259 		break;
5260 
5261 	case MOD_UNLOAD:
5262 		PDEBUG(("Unloading module: driver %s from bus %s",
5263 		    DRIVERNAME(dmd->dmd_driver),
5264 		    dmd->dmd_busname));
5265 		error = devclass_delete_driver(bus_devclass,
5266 		    dmd->dmd_driver);
5267 
5268 		if (!error && dmd->dmd_chainevh)
5269 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5270 		break;
5271 	case MOD_QUIESCE:
5272 		PDEBUG(("Quiesce module: driver %s from bus %s",
5273 		    DRIVERNAME(dmd->dmd_driver),
5274 		    dmd->dmd_busname));
5275 		error = devclass_quiesce_driver(bus_devclass,
5276 		    dmd->dmd_driver);
5277 
5278 		if (!error && dmd->dmd_chainevh)
5279 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5280 		break;
5281 	default:
5282 		error = EOPNOTSUPP;
5283 		break;
5284 	}
5285 
5286 	return (error);
5287 }
5288 
5289 /**
5290  * @brief Enumerate all hinted devices for this bus.
5291  *
5292  * Walks through the hints for this bus and calls the bus_hinted_child
5293  * routine for each one it fines.  It searches first for the specific
5294  * bus that's being probed for hinted children (eg isa0), and then for
5295  * generic children (eg isa).
5296  *
5297  * @param	dev	bus device to enumerate
5298  */
5299 void
5300 bus_enumerate_hinted_children(device_t bus)
5301 {
5302 	int i;
5303 	const char *dname, *busname;
5304 	int dunit;
5305 
5306 	/*
5307 	 * enumerate all devices on the specific bus
5308 	 */
5309 	busname = device_get_nameunit(bus);
5310 	i = 0;
5311 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5312 		BUS_HINTED_CHILD(bus, dname, dunit);
5313 
5314 	/*
5315 	 * and all the generic ones.
5316 	 */
5317 	busname = device_get_name(bus);
5318 	i = 0;
5319 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5320 		BUS_HINTED_CHILD(bus, dname, dunit);
5321 }
5322 
5323 #ifdef BUS_DEBUG
5324 
5325 /* the _short versions avoid iteration by not calling anything that prints
5326  * more than oneliners. I love oneliners.
5327  */
5328 
5329 static void
5330 print_device_short(device_t dev, int indent)
5331 {
5332 	if (!dev)
5333 		return;
5334 
5335 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5336 	    dev->unit, dev->desc,
5337 	    (dev->parent? "":"no "),
5338 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5339 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5340 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5341 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5342 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5343 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5344 	    (dev->ivars? "":"no "),
5345 	    (dev->softc? "":"no "),
5346 	    dev->busy));
5347 }
5348 
5349 static void
5350 print_device(device_t dev, int indent)
5351 {
5352 	if (!dev)
5353 		return;
5354 
5355 	print_device_short(dev, indent);
5356 
5357 	indentprintf(("Parent:\n"));
5358 	print_device_short(dev->parent, indent+1);
5359 	indentprintf(("Driver:\n"));
5360 	print_driver_short(dev->driver, indent+1);
5361 	indentprintf(("Devclass:\n"));
5362 	print_devclass_short(dev->devclass, indent+1);
5363 }
5364 
5365 void
5366 print_device_tree_short(device_t dev, int indent)
5367 /* print the device and all its children (indented) */
5368 {
5369 	device_t child;
5370 
5371 	if (!dev)
5372 		return;
5373 
5374 	print_device_short(dev, indent);
5375 
5376 	TAILQ_FOREACH(child, &dev->children, link) {
5377 		print_device_tree_short(child, indent+1);
5378 	}
5379 }
5380 
5381 void
5382 print_device_tree(device_t dev, int indent)
5383 /* print the device and all its children (indented) */
5384 {
5385 	device_t child;
5386 
5387 	if (!dev)
5388 		return;
5389 
5390 	print_device(dev, indent);
5391 
5392 	TAILQ_FOREACH(child, &dev->children, link) {
5393 		print_device_tree(child, indent+1);
5394 	}
5395 }
5396 
5397 static void
5398 print_driver_short(driver_t *driver, int indent)
5399 {
5400 	if (!driver)
5401 		return;
5402 
5403 	indentprintf(("driver %s: softc size = %zd\n",
5404 	    driver->name, driver->size));
5405 }
5406 
5407 static void
5408 print_driver(driver_t *driver, int indent)
5409 {
5410 	if (!driver)
5411 		return;
5412 
5413 	print_driver_short(driver, indent);
5414 }
5415 
5416 static void
5417 print_driver_list(driver_list_t drivers, int indent)
5418 {
5419 	driverlink_t driver;
5420 
5421 	TAILQ_FOREACH(driver, &drivers, link) {
5422 		print_driver(driver->driver, indent);
5423 	}
5424 }
5425 
5426 static void
5427 print_devclass_short(devclass_t dc, int indent)
5428 {
5429 	if ( !dc )
5430 		return;
5431 
5432 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5433 }
5434 
5435 static void
5436 print_devclass(devclass_t dc, int indent)
5437 {
5438 	int i;
5439 
5440 	if ( !dc )
5441 		return;
5442 
5443 	print_devclass_short(dc, indent);
5444 	indentprintf(("Drivers:\n"));
5445 	print_driver_list(dc->drivers, indent+1);
5446 
5447 	indentprintf(("Devices:\n"));
5448 	for (i = 0; i < dc->maxunit; i++)
5449 		if (dc->devices[i])
5450 			print_device(dc->devices[i], indent+1);
5451 }
5452 
5453 void
5454 print_devclass_list_short(void)
5455 {
5456 	devclass_t dc;
5457 
5458 	printf("Short listing of devclasses, drivers & devices:\n");
5459 	TAILQ_FOREACH(dc, &devclasses, link) {
5460 		print_devclass_short(dc, 0);
5461 	}
5462 }
5463 
5464 void
5465 print_devclass_list(void)
5466 {
5467 	devclass_t dc;
5468 
5469 	printf("Full listing of devclasses, drivers & devices:\n");
5470 	TAILQ_FOREACH(dc, &devclasses, link) {
5471 		print_devclass(dc, 0);
5472 	}
5473 }
5474 
5475 #endif
5476 
5477 /*
5478  * User-space access to the device tree.
5479  *
5480  * We implement a small set of nodes:
5481  *
5482  * hw.bus			Single integer read method to obtain the
5483  *				current generation count.
5484  * hw.bus.devices		Reads the entire device tree in flat space.
5485  * hw.bus.rman			Resource manager interface
5486  *
5487  * We might like to add the ability to scan devclasses and/or drivers to
5488  * determine what else is currently loaded/available.
5489  */
5490 
5491 static int
5492 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5493 {
5494 	struct u_businfo	ubus;
5495 
5496 	ubus.ub_version = BUS_USER_VERSION;
5497 	ubus.ub_generation = bus_data_generation;
5498 
5499 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5500 }
5501 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5502     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5503     "bus-related data");
5504 
5505 static int
5506 sysctl_devices(SYSCTL_HANDLER_ARGS)
5507 {
5508 	struct sbuf		sb;
5509 	int			*name = (int *)arg1;
5510 	u_int			namelen = arg2;
5511 	int			index;
5512 	device_t		dev;
5513 	struct u_device		*udev;
5514 	int			error;
5515 
5516 	if (namelen != 2)
5517 		return (EINVAL);
5518 
5519 	if (bus_data_generation_check(name[0]))
5520 		return (EINVAL);
5521 
5522 	index = name[1];
5523 
5524 	/*
5525 	 * Scan the list of devices, looking for the requested index.
5526 	 */
5527 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5528 		if (index-- == 0)
5529 			break;
5530 	}
5531 	if (dev == NULL)
5532 		return (ENOENT);
5533 
5534 	/*
5535 	 * Populate the return item, careful not to overflow the buffer.
5536 	 */
5537 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5538 	if (udev == NULL)
5539 		return (ENOMEM);
5540 	udev->dv_handle = (uintptr_t)dev;
5541 	udev->dv_parent = (uintptr_t)dev->parent;
5542 	udev->dv_devflags = dev->devflags;
5543 	udev->dv_flags = dev->flags;
5544 	udev->dv_state = dev->state;
5545 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5546 	if (dev->nameunit != NULL)
5547 		sbuf_cat(&sb, dev->nameunit);
5548 	sbuf_putc(&sb, '\0');
5549 	if (dev->desc != NULL)
5550 		sbuf_cat(&sb, dev->desc);
5551 	sbuf_putc(&sb, '\0');
5552 	if (dev->driver != NULL)
5553 		sbuf_cat(&sb, dev->driver->name);
5554 	sbuf_putc(&sb, '\0');
5555 	bus_child_pnpinfo(dev, &sb);
5556 	sbuf_putc(&sb, '\0');
5557 	bus_child_location(dev, &sb);
5558 	sbuf_putc(&sb, '\0');
5559 	error = sbuf_finish(&sb);
5560 	if (error == 0)
5561 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5562 	sbuf_delete(&sb);
5563 	free(udev, M_BUS);
5564 	return (error);
5565 }
5566 
5567 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5568     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5569     "system device tree");
5570 
5571 int
5572 bus_data_generation_check(int generation)
5573 {
5574 	if (generation != bus_data_generation)
5575 		return (1);
5576 
5577 	/* XXX generate optimised lists here? */
5578 	return (0);
5579 }
5580 
5581 void
5582 bus_data_generation_update(void)
5583 {
5584 	atomic_add_int(&bus_data_generation, 1);
5585 }
5586 
5587 int
5588 bus_free_resource(device_t dev, int type, struct resource *r)
5589 {
5590 	if (r == NULL)
5591 		return (0);
5592 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5593 }
5594 
5595 device_t
5596 device_lookup_by_name(const char *name)
5597 {
5598 	device_t dev;
5599 
5600 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5601 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5602 			return (dev);
5603 	}
5604 	return (NULL);
5605 }
5606 
5607 /*
5608  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5609  * implicit semantics on open, so it could not be reused for this.
5610  * Another option would be to call this /dev/bus?
5611  */
5612 static int
5613 find_device(struct devreq *req, device_t *devp)
5614 {
5615 	device_t dev;
5616 
5617 	/*
5618 	 * First, ensure that the name is nul terminated.
5619 	 */
5620 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5621 		return (EINVAL);
5622 
5623 	/*
5624 	 * Second, try to find an attached device whose name matches
5625 	 * 'name'.
5626 	 */
5627 	dev = device_lookup_by_name(req->dr_name);
5628 	if (dev != NULL) {
5629 		*devp = dev;
5630 		return (0);
5631 	}
5632 
5633 	/* Finally, give device enumerators a chance. */
5634 	dev = NULL;
5635 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5636 	if (dev == NULL)
5637 		return (ENOENT);
5638 	*devp = dev;
5639 	return (0);
5640 }
5641 
5642 static bool
5643 driver_exists(device_t bus, const char *driver)
5644 {
5645 	devclass_t dc;
5646 
5647 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5648 		if (devclass_find_driver_internal(dc, driver) != NULL)
5649 			return (true);
5650 	}
5651 	return (false);
5652 }
5653 
5654 static void
5655 device_gen_nomatch(device_t dev)
5656 {
5657 	device_t child;
5658 
5659 	if (dev->flags & DF_NEEDNOMATCH &&
5660 	    dev->state == DS_NOTPRESENT) {
5661 		BUS_PROBE_NOMATCH(dev->parent, dev);
5662 		devnomatch(dev);
5663 		dev->flags |= DF_DONENOMATCH;
5664 	}
5665 	dev->flags &= ~DF_NEEDNOMATCH;
5666 	TAILQ_FOREACH(child, &dev->children, link) {
5667 		device_gen_nomatch(child);
5668 	}
5669 }
5670 
5671 static void
5672 device_do_deferred_actions(void)
5673 {
5674 	devclass_t dc;
5675 	driverlink_t dl;
5676 
5677 	/*
5678 	 * Walk through the devclasses to find all the drivers we've tagged as
5679 	 * deferred during the freeze and call the driver added routines. They
5680 	 * have already been added to the lists in the background, so the driver
5681 	 * added routines that trigger a probe will have all the right bidders
5682 	 * for the probe auction.
5683 	 */
5684 	TAILQ_FOREACH(dc, &devclasses, link) {
5685 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5686 			if (dl->flags & DL_DEFERRED_PROBE) {
5687 				devclass_driver_added(dc, dl->driver);
5688 				dl->flags &= ~DL_DEFERRED_PROBE;
5689 			}
5690 		}
5691 	}
5692 
5693 	/*
5694 	 * We also defer no-match events during a freeze. Walk the tree and
5695 	 * generate all the pent-up events that are still relevant.
5696 	 */
5697 	device_gen_nomatch(root_bus);
5698 	bus_data_generation_update();
5699 }
5700 
5701 static int
5702 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5703     struct thread *td)
5704 {
5705 	struct devreq *req;
5706 	device_t dev;
5707 	int error, old;
5708 
5709 	/* Locate the device to control. */
5710 	mtx_lock(&Giant);
5711 	req = (struct devreq *)data;
5712 	switch (cmd) {
5713 	case DEV_ATTACH:
5714 	case DEV_DETACH:
5715 	case DEV_ENABLE:
5716 	case DEV_DISABLE:
5717 	case DEV_SUSPEND:
5718 	case DEV_RESUME:
5719 	case DEV_SET_DRIVER:
5720 	case DEV_CLEAR_DRIVER:
5721 	case DEV_RESCAN:
5722 	case DEV_DELETE:
5723 	case DEV_RESET:
5724 		error = priv_check(td, PRIV_DRIVER);
5725 		if (error == 0)
5726 			error = find_device(req, &dev);
5727 		break;
5728 	case DEV_FREEZE:
5729 	case DEV_THAW:
5730 		error = priv_check(td, PRIV_DRIVER);
5731 		break;
5732 	default:
5733 		error = ENOTTY;
5734 		break;
5735 	}
5736 	if (error) {
5737 		mtx_unlock(&Giant);
5738 		return (error);
5739 	}
5740 
5741 	/* Perform the requested operation. */
5742 	switch (cmd) {
5743 	case DEV_ATTACH:
5744 		if (device_is_attached(dev))
5745 			error = EBUSY;
5746 		else if (!device_is_enabled(dev))
5747 			error = ENXIO;
5748 		else
5749 			error = device_probe_and_attach(dev);
5750 		break;
5751 	case DEV_DETACH:
5752 		if (!device_is_attached(dev)) {
5753 			error = ENXIO;
5754 			break;
5755 		}
5756 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5757 			error = device_quiesce(dev);
5758 			if (error)
5759 				break;
5760 		}
5761 		error = device_detach(dev);
5762 		break;
5763 	case DEV_ENABLE:
5764 		if (device_is_enabled(dev)) {
5765 			error = EBUSY;
5766 			break;
5767 		}
5768 
5769 		/*
5770 		 * If the device has been probed but not attached (e.g.
5771 		 * when it has been disabled by a loader hint), just
5772 		 * attach the device rather than doing a full probe.
5773 		 */
5774 		device_enable(dev);
5775 		if (device_is_alive(dev)) {
5776 			/*
5777 			 * If the device was disabled via a hint, clear
5778 			 * the hint.
5779 			 */
5780 			if (resource_disabled(dev->driver->name, dev->unit))
5781 				resource_unset_value(dev->driver->name,
5782 				    dev->unit, "disabled");
5783 			error = device_attach(dev);
5784 		} else
5785 			error = device_probe_and_attach(dev);
5786 		break;
5787 	case DEV_DISABLE:
5788 		if (!device_is_enabled(dev)) {
5789 			error = ENXIO;
5790 			break;
5791 		}
5792 
5793 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5794 			error = device_quiesce(dev);
5795 			if (error)
5796 				break;
5797 		}
5798 
5799 		/*
5800 		 * Force DF_FIXEDCLASS on around detach to preserve
5801 		 * the existing name.
5802 		 */
5803 		old = dev->flags;
5804 		dev->flags |= DF_FIXEDCLASS;
5805 		error = device_detach(dev);
5806 		if (!(old & DF_FIXEDCLASS))
5807 			dev->flags &= ~DF_FIXEDCLASS;
5808 		if (error == 0)
5809 			device_disable(dev);
5810 		break;
5811 	case DEV_SUSPEND:
5812 		if (device_is_suspended(dev)) {
5813 			error = EBUSY;
5814 			break;
5815 		}
5816 		if (device_get_parent(dev) == NULL) {
5817 			error = EINVAL;
5818 			break;
5819 		}
5820 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5821 		break;
5822 	case DEV_RESUME:
5823 		if (!device_is_suspended(dev)) {
5824 			error = EINVAL;
5825 			break;
5826 		}
5827 		if (device_get_parent(dev) == NULL) {
5828 			error = EINVAL;
5829 			break;
5830 		}
5831 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5832 		break;
5833 	case DEV_SET_DRIVER: {
5834 		devclass_t dc;
5835 		char driver[128];
5836 
5837 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5838 		if (error)
5839 			break;
5840 		if (driver[0] == '\0') {
5841 			error = EINVAL;
5842 			break;
5843 		}
5844 		if (dev->devclass != NULL &&
5845 		    strcmp(driver, dev->devclass->name) == 0)
5846 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5847 			break;
5848 
5849 		/*
5850 		 * Scan drivers for this device's bus looking for at
5851 		 * least one matching driver.
5852 		 */
5853 		if (dev->parent == NULL) {
5854 			error = EINVAL;
5855 			break;
5856 		}
5857 		if (!driver_exists(dev->parent, driver)) {
5858 			error = ENOENT;
5859 			break;
5860 		}
5861 		dc = devclass_create(driver);
5862 		if (dc == NULL) {
5863 			error = ENOMEM;
5864 			break;
5865 		}
5866 
5867 		/* Detach device if necessary. */
5868 		if (device_is_attached(dev)) {
5869 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5870 				error = device_detach(dev);
5871 			else
5872 				error = EBUSY;
5873 			if (error)
5874 				break;
5875 		}
5876 
5877 		/* Clear any previously-fixed device class and unit. */
5878 		if (dev->flags & DF_FIXEDCLASS)
5879 			devclass_delete_device(dev->devclass, dev);
5880 		dev->flags |= DF_WILDCARD;
5881 		dev->unit = -1;
5882 
5883 		/* Force the new device class. */
5884 		error = devclass_add_device(dc, dev);
5885 		if (error)
5886 			break;
5887 		dev->flags |= DF_FIXEDCLASS;
5888 		error = device_probe_and_attach(dev);
5889 		break;
5890 	}
5891 	case DEV_CLEAR_DRIVER:
5892 		if (!(dev->flags & DF_FIXEDCLASS)) {
5893 			error = 0;
5894 			break;
5895 		}
5896 		if (device_is_attached(dev)) {
5897 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5898 				error = device_detach(dev);
5899 			else
5900 				error = EBUSY;
5901 			if (error)
5902 				break;
5903 		}
5904 
5905 		dev->flags &= ~DF_FIXEDCLASS;
5906 		dev->flags |= DF_WILDCARD;
5907 		devclass_delete_device(dev->devclass, dev);
5908 		error = device_probe_and_attach(dev);
5909 		break;
5910 	case DEV_RESCAN:
5911 		if (!device_is_attached(dev)) {
5912 			error = ENXIO;
5913 			break;
5914 		}
5915 		error = BUS_RESCAN(dev);
5916 		break;
5917 	case DEV_DELETE: {
5918 		device_t parent;
5919 
5920 		parent = device_get_parent(dev);
5921 		if (parent == NULL) {
5922 			error = EINVAL;
5923 			break;
5924 		}
5925 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5926 			if (bus_child_present(dev) != 0) {
5927 				error = EBUSY;
5928 				break;
5929 			}
5930 		}
5931 
5932 		error = device_delete_child(parent, dev);
5933 		break;
5934 	}
5935 	case DEV_FREEZE:
5936 		if (device_frozen)
5937 			error = EBUSY;
5938 		else
5939 			device_frozen = true;
5940 		break;
5941 	case DEV_THAW:
5942 		if (!device_frozen)
5943 			error = EBUSY;
5944 		else {
5945 			device_do_deferred_actions();
5946 			device_frozen = false;
5947 		}
5948 		break;
5949 	case DEV_RESET:
5950 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5951 			error = EINVAL;
5952 			break;
5953 		}
5954 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5955 		    req->dr_flags);
5956 		break;
5957 	}
5958 	mtx_unlock(&Giant);
5959 	return (error);
5960 }
5961 
5962 static struct cdevsw devctl2_cdevsw = {
5963 	.d_version =	D_VERSION,
5964 	.d_ioctl =	devctl2_ioctl,
5965 	.d_name =	"devctl2",
5966 };
5967 
5968 static void
5969 devctl2_init(void)
5970 {
5971 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5972 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5973 }
5974 
5975 /*
5976  * APIs to manage deprecation and obsolescence.
5977  */
5978 static int obsolete_panic = 0;
5979 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
5980     "Panic when obsolete features are used (0 = never, 1 = if obsolete, "
5981     "2 = if deprecated)");
5982 
5983 static void
5984 gone_panic(int major, int running, const char *msg)
5985 {
5986 	switch (obsolete_panic)
5987 	{
5988 	case 0:
5989 		return;
5990 	case 1:
5991 		if (running < major)
5992 			return;
5993 		/* FALLTHROUGH */
5994 	default:
5995 		panic("%s", msg);
5996 	}
5997 }
5998 
5999 void
6000 _gone_in(int major, const char *msg)
6001 {
6002 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6003 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6004 		printf("Obsolete code will be removed soon: %s\n", msg);
6005 	else
6006 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6007 		    major, msg);
6008 }
6009 
6010 void
6011 _gone_in_dev(device_t dev, int major, const char *msg)
6012 {
6013 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6014 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6015 		device_printf(dev,
6016 		    "Obsolete code will be removed soon: %s\n", msg);
6017 	else
6018 		device_printf(dev,
6019 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6020 		    major, msg);
6021 }
6022 
6023 #ifdef DDB
6024 DB_SHOW_COMMAND(device, db_show_device)
6025 {
6026 	device_t dev;
6027 
6028 	if (!have_addr)
6029 		return;
6030 
6031 	dev = (device_t)addr;
6032 
6033 	db_printf("name:    %s\n", device_get_nameunit(dev));
6034 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6035 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6036 	db_printf("  addr:    %p\n", dev);
6037 	db_printf("  parent:  %p\n", dev->parent);
6038 	db_printf("  softc:   %p\n", dev->softc);
6039 	db_printf("  ivars:   %p\n", dev->ivars);
6040 }
6041 
6042 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6043 {
6044 	device_t dev;
6045 
6046 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6047 		db_show_device((db_expr_t)dev, true, count, modif);
6048 	}
6049 }
6050 #endif
6051