xref: /freebsd/sys/kern/subr_bus.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/rman.h>
55 #include <sys/sbuf.h>
56 #include <sys/selinfo.h>
57 #include <sys/signalvar.h>
58 #include <sys/smp.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61 #include <sys/uio.h>
62 #include <sys/bus.h>
63 #include <sys/cpuset.h>
64 
65 #include <net/vnet.h>
66 
67 #include <machine/cpu.h>
68 #include <machine/stdarg.h>
69 
70 #include <vm/uma.h>
71 #include <vm/vm.h>
72 
73 #include <ddb/ddb.h>
74 
75 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
76     NULL);
77 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
78     NULL);
79 
80 /*
81  * Used to attach drivers to devclasses.
82  */
83 typedef struct driverlink *driverlink_t;
84 struct driverlink {
85 	kobj_class_t	driver;
86 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
87 	int		pass;
88 	int		flags;
89 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
90 	TAILQ_ENTRY(driverlink) passlink;
91 };
92 
93 /*
94  * Forward declarations
95  */
96 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
97 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
98 typedef TAILQ_HEAD(device_list, _device) device_list_t;
99 
100 struct devclass {
101 	TAILQ_ENTRY(devclass) link;
102 	devclass_t	parent;		/* parent in devclass hierarchy */
103 	driver_list_t	drivers;	/* bus devclasses store drivers for bus */
104 	char		*name;
105 	device_t	*devices;	/* array of devices indexed by unit */
106 	int		maxunit;	/* size of devices array */
107 	int		flags;
108 #define DC_HAS_CHILDREN		1
109 
110 	struct sysctl_ctx_list sysctl_ctx;
111 	struct sysctl_oid *sysctl_tree;
112 };
113 
114 /**
115  * @brief Implementation of _device.
116  *
117  * The structure is named "_device" instead of "device" to avoid type confusion
118  * caused by other subsystems defining a (struct device).
119  */
120 struct _device {
121 	/*
122 	 * A device is a kernel object. The first field must be the
123 	 * current ops table for the object.
124 	 */
125 	KOBJ_FIELDS;
126 
127 	/*
128 	 * Device hierarchy.
129 	 */
130 	TAILQ_ENTRY(_device)	link;	/**< list of devices in parent */
131 	TAILQ_ENTRY(_device)	devlink; /**< global device list membership */
132 	device_t	parent;		/**< parent of this device  */
133 	device_list_t	children;	/**< list of child devices */
134 
135 	/*
136 	 * Details of this device.
137 	 */
138 	driver_t	*driver;	/**< current driver */
139 	devclass_t	devclass;	/**< current device class */
140 	int		unit;		/**< current unit number */
141 	char*		nameunit;	/**< name+unit e.g. foodev0 */
142 	char*		desc;		/**< driver specific description */
143 	int		busy;		/**< count of calls to device_busy() */
144 	device_state_t	state;		/**< current device state  */
145 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
146 	u_int		flags;		/**< internal device flags  */
147 	u_int	order;			/**< order from device_add_child_ordered() */
148 	void	*ivars;			/**< instance variables  */
149 	void	*softc;			/**< current driver's variables  */
150 
151 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
152 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
153 };
154 
155 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
156 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
157 
158 EVENTHANDLER_LIST_DEFINE(device_attach);
159 EVENTHANDLER_LIST_DEFINE(device_detach);
160 EVENTHANDLER_LIST_DEFINE(dev_lookup);
161 
162 static void devctl2_init(void);
163 static bool device_frozen;
164 
165 #define DRIVERNAME(d)	((d)? d->name : "no driver")
166 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
167 
168 #ifdef BUS_DEBUG
169 
170 static int bus_debug = 1;
171 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
172     "Bus debug level");
173 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
174 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
175 
176 /**
177  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
178  * prevent syslog from deleting initial spaces
179  */
180 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
181 
182 static void print_device_short(device_t dev, int indent);
183 static void print_device(device_t dev, int indent);
184 void print_device_tree_short(device_t dev, int indent);
185 void print_device_tree(device_t dev, int indent);
186 static void print_driver_short(driver_t *driver, int indent);
187 static void print_driver(driver_t *driver, int indent);
188 static void print_driver_list(driver_list_t drivers, int indent);
189 static void print_devclass_short(devclass_t dc, int indent);
190 static void print_devclass(devclass_t dc, int indent);
191 void print_devclass_list_short(void);
192 void print_devclass_list(void);
193 
194 #else
195 /* Make the compiler ignore the function calls */
196 #define PDEBUG(a)			/* nop */
197 #define DEVICENAME(d)			/* nop */
198 
199 #define print_device_short(d,i)		/* nop */
200 #define print_device(d,i)		/* nop */
201 #define print_device_tree_short(d,i)	/* nop */
202 #define print_device_tree(d,i)		/* nop */
203 #define print_driver_short(d,i)		/* nop */
204 #define print_driver(d,i)		/* nop */
205 #define print_driver_list(d,i)		/* nop */
206 #define print_devclass_short(d,i)	/* nop */
207 #define print_devclass(d,i)		/* nop */
208 #define print_devclass_list_short()	/* nop */
209 #define print_devclass_list()		/* nop */
210 #endif
211 
212 /*
213  * dev sysctl tree
214  */
215 
216 enum {
217 	DEVCLASS_SYSCTL_PARENT,
218 };
219 
220 static int
221 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
222 {
223 	devclass_t dc = (devclass_t)arg1;
224 	const char *value;
225 
226 	switch (arg2) {
227 	case DEVCLASS_SYSCTL_PARENT:
228 		value = dc->parent ? dc->parent->name : "";
229 		break;
230 	default:
231 		return (EINVAL);
232 	}
233 	return (SYSCTL_OUT_STR(req, value));
234 }
235 
236 static void
237 devclass_sysctl_init(devclass_t dc)
238 {
239 	if (dc->sysctl_tree != NULL)
240 		return;
241 	sysctl_ctx_init(&dc->sysctl_ctx);
242 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
243 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
244 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
245 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
246 	    OID_AUTO, "%parent",
247 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
248 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
249 	    "parent class");
250 }
251 
252 enum {
253 	DEVICE_SYSCTL_DESC,
254 	DEVICE_SYSCTL_DRIVER,
255 	DEVICE_SYSCTL_LOCATION,
256 	DEVICE_SYSCTL_PNPINFO,
257 	DEVICE_SYSCTL_PARENT,
258 };
259 
260 static int
261 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
262 {
263 	struct sbuf sb;
264 	device_t dev = (device_t)arg1;
265 	int error;
266 
267 	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
268 	sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
269 	switch (arg2) {
270 	case DEVICE_SYSCTL_DESC:
271 		sbuf_cat(&sb, dev->desc ? dev->desc : "");
272 		break;
273 	case DEVICE_SYSCTL_DRIVER:
274 		sbuf_cat(&sb, dev->driver ? dev->driver->name : "");
275 		break;
276 	case DEVICE_SYSCTL_LOCATION:
277 		bus_child_location(dev, &sb);
278 		break;
279 	case DEVICE_SYSCTL_PNPINFO:
280 		bus_child_pnpinfo(dev, &sb);
281 		break;
282 	case DEVICE_SYSCTL_PARENT:
283 		sbuf_cat(&sb, dev->parent ? dev->parent->nameunit : "");
284 		break;
285 	default:
286 		sbuf_delete(&sb);
287 		return (EINVAL);
288 	}
289 	error = sbuf_finish(&sb);
290 	sbuf_delete(&sb);
291 	return (error);
292 }
293 
294 static void
295 device_sysctl_init(device_t dev)
296 {
297 	devclass_t dc = dev->devclass;
298 	int domain;
299 
300 	if (dev->sysctl_tree != NULL)
301 		return;
302 	devclass_sysctl_init(dc);
303 	sysctl_ctx_init(&dev->sysctl_ctx);
304 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
305 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
306 	    dev->nameunit + strlen(dc->name),
307 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
308 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
309 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
310 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
311 	    "device description");
312 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
313 	    OID_AUTO, "%driver",
314 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
315 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
316 	    "device driver name");
317 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
318 	    OID_AUTO, "%location",
319 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
320 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
321 	    "device location relative to parent");
322 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
323 	    OID_AUTO, "%pnpinfo",
324 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
325 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
326 	    "device identification");
327 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
328 	    OID_AUTO, "%parent",
329 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
330 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
331 	    "parent device");
332 	if (bus_get_domain(dev, &domain) == 0)
333 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
334 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
335 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
336 }
337 
338 static void
339 device_sysctl_update(device_t dev)
340 {
341 	devclass_t dc = dev->devclass;
342 
343 	if (dev->sysctl_tree == NULL)
344 		return;
345 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
346 }
347 
348 static void
349 device_sysctl_fini(device_t dev)
350 {
351 	if (dev->sysctl_tree == NULL)
352 		return;
353 	sysctl_ctx_free(&dev->sysctl_ctx);
354 	dev->sysctl_tree = NULL;
355 }
356 
357 /*
358  * /dev/devctl implementation
359  */
360 
361 /*
362  * This design allows only one reader for /dev/devctl.  This is not desirable
363  * in the long run, but will get a lot of hair out of this implementation.
364  * Maybe we should make this device a clonable device.
365  *
366  * Also note: we specifically do not attach a device to the device_t tree
367  * to avoid potential chicken and egg problems.  One could argue that all
368  * of this belongs to the root node.
369  */
370 
371 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
372 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
373 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
374 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
375     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
376 
377 static d_open_t		devopen;
378 static d_close_t	devclose;
379 static d_read_t		devread;
380 static d_ioctl_t	devioctl;
381 static d_poll_t		devpoll;
382 static d_kqfilter_t	devkqfilter;
383 
384 static struct cdevsw dev_cdevsw = {
385 	.d_version =	D_VERSION,
386 	.d_open =	devopen,
387 	.d_close =	devclose,
388 	.d_read =	devread,
389 	.d_ioctl =	devioctl,
390 	.d_poll =	devpoll,
391 	.d_kqfilter =	devkqfilter,
392 	.d_name =	"devctl",
393 };
394 
395 #define DEVCTL_BUFFER (1024 - sizeof(void *))
396 struct dev_event_info {
397 	STAILQ_ENTRY(dev_event_info) dei_link;
398 	char dei_data[DEVCTL_BUFFER];
399 };
400 
401 STAILQ_HEAD(devq, dev_event_info);
402 
403 static struct dev_softc {
404 	int		inuse;
405 	int		nonblock;
406 	int		queued;
407 	int		async;
408 	struct mtx	mtx;
409 	struct cv	cv;
410 	struct selinfo	sel;
411 	struct devq	devq;
412 	struct sigio	*sigio;
413 	uma_zone_t	zone;
414 } devsoftc;
415 
416 static void	filt_devctl_detach(struct knote *kn);
417 static int	filt_devctl_read(struct knote *kn, long hint);
418 
419 struct filterops devctl_rfiltops = {
420 	.f_isfd = 1,
421 	.f_detach = filt_devctl_detach,
422 	.f_event = filt_devctl_read,
423 };
424 
425 static struct cdev *devctl_dev;
426 
427 static void
428 devinit(void)
429 {
430 	int reserve;
431 	uma_zone_t z;
432 
433 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
434 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
435 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
436 	cv_init(&devsoftc.cv, "dev cv");
437 	STAILQ_INIT(&devsoftc.devq);
438 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
439 	if (devctl_queue_length > 0) {
440 		/*
441 		 * Allocate a zone for the messages. Preallocate 2% of these for
442 		 * a reserve. Allow only devctl_queue_length slabs to cap memory
443 		 * usage.  The reserve usually allows coverage of surges of
444 		 * events during memory shortages. Normally we won't have to
445 		 * re-use events from the queue, but will in extreme shortages.
446 		 */
447 		z = devsoftc.zone = uma_zcreate("DEVCTL",
448 		    sizeof(struct dev_event_info), NULL, NULL, NULL, NULL,
449 		    UMA_ALIGN_PTR, 0);
450 		reserve = max(devctl_queue_length / 50, 100);	/* 2% reserve */
451 		uma_zone_set_max(z, devctl_queue_length);
452 		uma_zone_set_maxcache(z, 0);
453 		uma_zone_reserve(z, reserve);
454 		uma_prealloc(z, reserve);
455 	}
456 	devctl2_init();
457 }
458 
459 static int
460 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
461 {
462 	mtx_lock(&devsoftc.mtx);
463 	if (devsoftc.inuse) {
464 		mtx_unlock(&devsoftc.mtx);
465 		return (EBUSY);
466 	}
467 	/* move to init */
468 	devsoftc.inuse = 1;
469 	mtx_unlock(&devsoftc.mtx);
470 	return (0);
471 }
472 
473 static int
474 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
475 {
476 	mtx_lock(&devsoftc.mtx);
477 	devsoftc.inuse = 0;
478 	devsoftc.nonblock = 0;
479 	devsoftc.async = 0;
480 	cv_broadcast(&devsoftc.cv);
481 	funsetown(&devsoftc.sigio);
482 	mtx_unlock(&devsoftc.mtx);
483 	return (0);
484 }
485 
486 /*
487  * The read channel for this device is used to report changes to
488  * userland in realtime.  We are required to free the data as well as
489  * the n1 object because we allocate them separately.  Also note that
490  * we return one record at a time.  If you try to read this device a
491  * character at a time, you will lose the rest of the data.  Listening
492  * programs are expected to cope.
493  */
494 static int
495 devread(struct cdev *dev, struct uio *uio, int ioflag)
496 {
497 	struct dev_event_info *n1;
498 	int rv;
499 
500 	mtx_lock(&devsoftc.mtx);
501 	while (STAILQ_EMPTY(&devsoftc.devq)) {
502 		if (devsoftc.nonblock) {
503 			mtx_unlock(&devsoftc.mtx);
504 			return (EAGAIN);
505 		}
506 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
507 		if (rv) {
508 			/*
509 			 * Need to translate ERESTART to EINTR here? -- jake
510 			 */
511 			mtx_unlock(&devsoftc.mtx);
512 			return (rv);
513 		}
514 	}
515 	n1 = STAILQ_FIRST(&devsoftc.devq);
516 	STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
517 	devsoftc.queued--;
518 	mtx_unlock(&devsoftc.mtx);
519 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
520 	uma_zfree(devsoftc.zone, n1);
521 	return (rv);
522 }
523 
524 static	int
525 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
526 {
527 	switch (cmd) {
528 	case FIONBIO:
529 		if (*(int*)data)
530 			devsoftc.nonblock = 1;
531 		else
532 			devsoftc.nonblock = 0;
533 		return (0);
534 	case FIOASYNC:
535 		if (*(int*)data)
536 			devsoftc.async = 1;
537 		else
538 			devsoftc.async = 0;
539 		return (0);
540 	case FIOSETOWN:
541 		return fsetown(*(int *)data, &devsoftc.sigio);
542 	case FIOGETOWN:
543 		*(int *)data = fgetown(&devsoftc.sigio);
544 		return (0);
545 
546 		/* (un)Support for other fcntl() calls. */
547 	case FIOCLEX:
548 	case FIONCLEX:
549 	case FIONREAD:
550 	default:
551 		break;
552 	}
553 	return (ENOTTY);
554 }
555 
556 static	int
557 devpoll(struct cdev *dev, int events, struct thread *td)
558 {
559 	int	revents = 0;
560 
561 	mtx_lock(&devsoftc.mtx);
562 	if (events & (POLLIN | POLLRDNORM)) {
563 		if (!STAILQ_EMPTY(&devsoftc.devq))
564 			revents = events & (POLLIN | POLLRDNORM);
565 		else
566 			selrecord(td, &devsoftc.sel);
567 	}
568 	mtx_unlock(&devsoftc.mtx);
569 
570 	return (revents);
571 }
572 
573 static int
574 devkqfilter(struct cdev *dev, struct knote *kn)
575 {
576 	int error;
577 
578 	if (kn->kn_filter == EVFILT_READ) {
579 		kn->kn_fop = &devctl_rfiltops;
580 		knlist_add(&devsoftc.sel.si_note, kn, 0);
581 		error = 0;
582 	} else
583 		error = EINVAL;
584 	return (error);
585 }
586 
587 static void
588 filt_devctl_detach(struct knote *kn)
589 {
590 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
591 }
592 
593 static int
594 filt_devctl_read(struct knote *kn, long hint)
595 {
596 	kn->kn_data = devsoftc.queued;
597 	return (kn->kn_data != 0);
598 }
599 
600 /**
601  * @brief Return whether the userland process is running
602  */
603 bool
604 devctl_process_running(void)
605 {
606 	return (devsoftc.inuse == 1);
607 }
608 
609 static struct dev_event_info *
610 devctl_alloc_dei(void)
611 {
612 	struct dev_event_info *dei = NULL;
613 
614 	mtx_lock(&devsoftc.mtx);
615 	if (devctl_queue_length == 0)
616 		goto out;
617 	dei = uma_zalloc(devsoftc.zone, M_NOWAIT);
618 	if (dei == NULL)
619 		dei = uma_zalloc(devsoftc.zone, M_NOWAIT | M_USE_RESERVE);
620 	if (dei == NULL) {
621 		/*
622 		 * Guard against no items in the queue. Normally, this won't
623 		 * happen, but if lots of events happen all at once and there's
624 		 * a chance we're out of allocated space but none have yet been
625 		 * queued when we get here, leaving nothing to steal. This can
626 		 * also happen with error injection. Fail safe by returning
627 		 * NULL in that case..
628 		 */
629 		if (devsoftc.queued == 0)
630 			goto out;
631 		dei = STAILQ_FIRST(&devsoftc.devq);
632 		STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
633 		devsoftc.queued--;
634 	}
635 	MPASS(dei != NULL);
636 	*dei->dei_data = '\0';
637 out:
638 	mtx_unlock(&devsoftc.mtx);
639 	return (dei);
640 }
641 
642 static struct dev_event_info *
643 devctl_alloc_dei_sb(struct sbuf *sb)
644 {
645 	struct dev_event_info *dei;
646 
647 	dei = devctl_alloc_dei();
648 	if (dei != NULL)
649 		sbuf_new(sb, dei->dei_data, sizeof(dei->dei_data), SBUF_FIXEDLEN);
650 	return (dei);
651 }
652 
653 static void
654 devctl_free_dei(struct dev_event_info *dei)
655 {
656 	uma_zfree(devsoftc.zone, dei);
657 }
658 
659 static void
660 devctl_queue(struct dev_event_info *dei)
661 {
662 	mtx_lock(&devsoftc.mtx);
663 	STAILQ_INSERT_TAIL(&devsoftc.devq, dei, dei_link);
664 	devsoftc.queued++;
665 	cv_broadcast(&devsoftc.cv);
666 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
667 	mtx_unlock(&devsoftc.mtx);
668 	selwakeup(&devsoftc.sel);
669 	if (devsoftc.async && devsoftc.sigio != NULL)
670 		pgsigio(&devsoftc.sigio, SIGIO, 0);
671 }
672 
673 /**
674  * @brief Send a 'notification' to userland, using standard ways
675  */
676 void
677 devctl_notify(const char *system, const char *subsystem, const char *type,
678     const char *data)
679 {
680 	struct dev_event_info *dei;
681 	struct sbuf sb;
682 
683 	if (system == NULL || subsystem == NULL || type == NULL)
684 		return;
685 	dei = devctl_alloc_dei_sb(&sb);
686 	if (dei == NULL)
687 		return;
688 	sbuf_cpy(&sb, "!system=");
689 	sbuf_cat(&sb, system);
690 	sbuf_cat(&sb, " subsystem=");
691 	sbuf_cat(&sb, subsystem);
692 	sbuf_cat(&sb, " type=");
693 	sbuf_cat(&sb, type);
694 	if (data != NULL) {
695 		sbuf_putc(&sb, ' ');
696 		sbuf_cat(&sb, data);
697 	}
698 	sbuf_putc(&sb, '\n');
699 	if (sbuf_finish(&sb) != 0)
700 		devctl_free_dei(dei);	/* overflow -> drop it */
701 	else
702 		devctl_queue(dei);
703 }
704 
705 /*
706  * Common routine that tries to make sending messages as easy as possible.
707  * We allocate memory for the data, copy strings into that, but do not
708  * free it unless there's an error.  The dequeue part of the driver should
709  * free the data.  We don't send data when the device is disabled.  We do
710  * send data, even when we have no listeners, because we wish to avoid
711  * races relating to startup and restart of listening applications.
712  *
713  * devaddq is designed to string together the type of event, with the
714  * object of that event, plus the plug and play info and location info
715  * for that event.  This is likely most useful for devices, but less
716  * useful for other consumers of this interface.  Those should use
717  * the devctl_notify() interface instead.
718  *
719  * Output:
720  *	${type}${what} at $(location dev) $(pnp-info dev) on $(parent dev)
721  */
722 static void
723 devaddq(const char *type, const char *what, device_t dev)
724 {
725 	struct dev_event_info *dei;
726 	const char *parstr;
727 	struct sbuf sb;
728 
729 	dei = devctl_alloc_dei_sb(&sb);
730 	if (dei == NULL)
731 		return;
732 	sbuf_cpy(&sb, type);
733 	sbuf_cat(&sb, what);
734 	sbuf_cat(&sb, " at ");
735 
736 	/* Add in the location */
737 	bus_child_location(dev, &sb);
738 	sbuf_putc(&sb, ' ');
739 
740 	/* Add in pnpinfo */
741 	bus_child_pnpinfo(dev, &sb);
742 
743 	/* Get the parent of this device, or / if high enough in the tree. */
744 	if (device_get_parent(dev) == NULL)
745 		parstr = ".";	/* Or '/' ? */
746 	else
747 		parstr = device_get_nameunit(device_get_parent(dev));
748 	sbuf_cat(&sb, " on ");
749 	sbuf_cat(&sb, parstr);
750 	sbuf_putc(&sb, '\n');
751 	if (sbuf_finish(&sb) != 0)
752 		goto bad;
753 	devctl_queue(dei);
754 	return;
755 bad:
756 	devctl_free_dei(dei);
757 }
758 
759 /*
760  * A device was added to the tree.  We are called just after it successfully
761  * attaches (that is, probe and attach success for this device).  No call
762  * is made if a device is merely parented into the tree.  See devnomatch
763  * if probe fails.  If attach fails, no notification is sent (but maybe
764  * we should have a different message for this).
765  */
766 static void
767 devadded(device_t dev)
768 {
769 	devaddq("+", device_get_nameunit(dev), dev);
770 }
771 
772 /*
773  * A device was removed from the tree.  We are called just before this
774  * happens.
775  */
776 static void
777 devremoved(device_t dev)
778 {
779 	devaddq("-", device_get_nameunit(dev), dev);
780 }
781 
782 /*
783  * Called when there's no match for this device.  This is only called
784  * the first time that no match happens, so we don't keep getting this
785  * message.  Should that prove to be undesirable, we can change it.
786  * This is called when all drivers that can attach to a given bus
787  * decline to accept this device.  Other errors may not be detected.
788  */
789 static void
790 devnomatch(device_t dev)
791 {
792 	devaddq("?", "", dev);
793 }
794 
795 static int
796 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
797 {
798 	int q, error;
799 
800 	q = devctl_queue_length;
801 	error = sysctl_handle_int(oidp, &q, 0, req);
802 	if (error || !req->newptr)
803 		return (error);
804 	if (q < 0)
805 		return (EINVAL);
806 
807 	/*
808 	 * When set as a tunable, we've not yet initialized the mutex.
809 	 * It is safe to just assign to devctl_queue_length and return
810 	 * as we're racing no one. We'll use whatever value set in
811 	 * devinit.
812 	 */
813 	if (!mtx_initialized(&devsoftc.mtx)) {
814 		devctl_queue_length = q;
815 		return (0);
816 	}
817 
818 	/*
819 	 * XXX It's hard to grow or shrink the UMA zone. Only allow
820 	 * disabling the queue size for the moment until underlying
821 	 * UMA issues can be sorted out.
822 	 */
823 	if (q != 0)
824 		return (EINVAL);
825 	if (q == devctl_queue_length)
826 		return (0);
827 	mtx_lock(&devsoftc.mtx);
828 	devctl_queue_length = 0;
829 	uma_zdestroy(devsoftc.zone);
830 	devsoftc.zone = 0;
831 	mtx_unlock(&devsoftc.mtx);
832 	return (0);
833 }
834 
835 /**
836  * @brief safely quotes strings that might have double quotes in them.
837  *
838  * The devctl protocol relies on quoted strings having matching quotes.
839  * This routine quotes any internal quotes so the resulting string
840  * is safe to pass to snprintf to construct, for example pnp info strings.
841  *
842  * @param sb	sbuf to place the characters into
843  * @param src	Original buffer.
844  */
845 void
846 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
847 {
848 	while (*src != '\0') {
849 		if (*src == '"' || *src == '\\')
850 			sbuf_putc(sb, '\\');
851 		sbuf_putc(sb, *src++);
852 	}
853 }
854 
855 /* End of /dev/devctl code */
856 
857 static struct device_list bus_data_devices;
858 static int bus_data_generation = 1;
859 
860 static kobj_method_t null_methods[] = {
861 	KOBJMETHOD_END
862 };
863 
864 DEFINE_CLASS(null, null_methods, 0);
865 
866 /*
867  * Bus pass implementation
868  */
869 
870 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
871 int bus_current_pass = BUS_PASS_ROOT;
872 
873 /**
874  * @internal
875  * @brief Register the pass level of a new driver attachment
876  *
877  * Register a new driver attachment's pass level.  If no driver
878  * attachment with the same pass level has been added, then @p new
879  * will be added to the global passes list.
880  *
881  * @param new		the new driver attachment
882  */
883 static void
884 driver_register_pass(struct driverlink *new)
885 {
886 	struct driverlink *dl;
887 
888 	/* We only consider pass numbers during boot. */
889 	if (bus_current_pass == BUS_PASS_DEFAULT)
890 		return;
891 
892 	/*
893 	 * Walk the passes list.  If we already know about this pass
894 	 * then there is nothing to do.  If we don't, then insert this
895 	 * driver link into the list.
896 	 */
897 	TAILQ_FOREACH(dl, &passes, passlink) {
898 		if (dl->pass < new->pass)
899 			continue;
900 		if (dl->pass == new->pass)
901 			return;
902 		TAILQ_INSERT_BEFORE(dl, new, passlink);
903 		return;
904 	}
905 	TAILQ_INSERT_TAIL(&passes, new, passlink);
906 }
907 
908 /**
909  * @brief Raise the current bus pass
910  *
911  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
912  * method on the root bus to kick off a new device tree scan for each
913  * new pass level that has at least one driver.
914  */
915 void
916 bus_set_pass(int pass)
917 {
918 	struct driverlink *dl;
919 
920 	if (bus_current_pass > pass)
921 		panic("Attempt to lower bus pass level");
922 
923 	TAILQ_FOREACH(dl, &passes, passlink) {
924 		/* Skip pass values below the current pass level. */
925 		if (dl->pass <= bus_current_pass)
926 			continue;
927 
928 		/*
929 		 * Bail once we hit a driver with a pass level that is
930 		 * too high.
931 		 */
932 		if (dl->pass > pass)
933 			break;
934 
935 		/*
936 		 * Raise the pass level to the next level and rescan
937 		 * the tree.
938 		 */
939 		bus_current_pass = dl->pass;
940 		BUS_NEW_PASS(root_bus);
941 	}
942 
943 	/*
944 	 * If there isn't a driver registered for the requested pass,
945 	 * then bus_current_pass might still be less than 'pass'.  Set
946 	 * it to 'pass' in that case.
947 	 */
948 	if (bus_current_pass < pass)
949 		bus_current_pass = pass;
950 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
951 }
952 
953 /*
954  * Devclass implementation
955  */
956 
957 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
958 
959 /**
960  * @internal
961  * @brief Find or create a device class
962  *
963  * If a device class with the name @p classname exists, return it,
964  * otherwise if @p create is non-zero create and return a new device
965  * class.
966  *
967  * If @p parentname is non-NULL, the parent of the devclass is set to
968  * the devclass of that name.
969  *
970  * @param classname	the devclass name to find or create
971  * @param parentname	the parent devclass name or @c NULL
972  * @param create	non-zero to create a devclass
973  */
974 static devclass_t
975 devclass_find_internal(const char *classname, const char *parentname,
976 		       int create)
977 {
978 	devclass_t dc;
979 
980 	PDEBUG(("looking for %s", classname));
981 	if (!classname)
982 		return (NULL);
983 
984 	TAILQ_FOREACH(dc, &devclasses, link) {
985 		if (!strcmp(dc->name, classname))
986 			break;
987 	}
988 
989 	if (create && !dc) {
990 		PDEBUG(("creating %s", classname));
991 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
992 		    M_BUS, M_NOWAIT | M_ZERO);
993 		if (!dc)
994 			return (NULL);
995 		dc->parent = NULL;
996 		dc->name = (char*) (dc + 1);
997 		strcpy(dc->name, classname);
998 		TAILQ_INIT(&dc->drivers);
999 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1000 
1001 		bus_data_generation_update();
1002 	}
1003 
1004 	/*
1005 	 * If a parent class is specified, then set that as our parent so
1006 	 * that this devclass will support drivers for the parent class as
1007 	 * well.  If the parent class has the same name don't do this though
1008 	 * as it creates a cycle that can trigger an infinite loop in
1009 	 * device_probe_child() if a device exists for which there is no
1010 	 * suitable driver.
1011 	 */
1012 	if (parentname && dc && !dc->parent &&
1013 	    strcmp(classname, parentname) != 0) {
1014 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1015 		dc->parent->flags |= DC_HAS_CHILDREN;
1016 	}
1017 
1018 	return (dc);
1019 }
1020 
1021 /**
1022  * @brief Create a device class
1023  *
1024  * If a device class with the name @p classname exists, return it,
1025  * otherwise create and return a new device class.
1026  *
1027  * @param classname	the devclass name to find or create
1028  */
1029 devclass_t
1030 devclass_create(const char *classname)
1031 {
1032 	return (devclass_find_internal(classname, NULL, TRUE));
1033 }
1034 
1035 /**
1036  * @brief Find a device class
1037  *
1038  * If a device class with the name @p classname exists, return it,
1039  * otherwise return @c NULL.
1040  *
1041  * @param classname	the devclass name to find
1042  */
1043 devclass_t
1044 devclass_find(const char *classname)
1045 {
1046 	return (devclass_find_internal(classname, NULL, FALSE));
1047 }
1048 
1049 /**
1050  * @brief Register that a device driver has been added to a devclass
1051  *
1052  * Register that a device driver has been added to a devclass.  This
1053  * is called by devclass_add_driver to accomplish the recursive
1054  * notification of all the children classes of dc, as well as dc.
1055  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1056  * the devclass.
1057  *
1058  * We do a full search here of the devclass list at each iteration
1059  * level to save storing children-lists in the devclass structure.  If
1060  * we ever move beyond a few dozen devices doing this, we may need to
1061  * reevaluate...
1062  *
1063  * @param dc		the devclass to edit
1064  * @param driver	the driver that was just added
1065  */
1066 static void
1067 devclass_driver_added(devclass_t dc, driver_t *driver)
1068 {
1069 	devclass_t parent;
1070 	int i;
1071 
1072 	/*
1073 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1074 	 */
1075 	for (i = 0; i < dc->maxunit; i++)
1076 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1077 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1078 
1079 	/*
1080 	 * Walk through the children classes.  Since we only keep a
1081 	 * single parent pointer around, we walk the entire list of
1082 	 * devclasses looking for children.  We set the
1083 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1084 	 * the parent, so we only walk the list for those devclasses
1085 	 * that have children.
1086 	 */
1087 	if (!(dc->flags & DC_HAS_CHILDREN))
1088 		return;
1089 	parent = dc;
1090 	TAILQ_FOREACH(dc, &devclasses, link) {
1091 		if (dc->parent == parent)
1092 			devclass_driver_added(dc, driver);
1093 	}
1094 }
1095 
1096 /**
1097  * @brief Add a device driver to a device class
1098  *
1099  * Add a device driver to a devclass. This is normally called
1100  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1101  * all devices in the devclass will be called to allow them to attempt
1102  * to re-probe any unmatched children.
1103  *
1104  * @param dc		the devclass to edit
1105  * @param driver	the driver to register
1106  */
1107 int
1108 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1109 {
1110 	driverlink_t dl;
1111 	const char *parentname;
1112 
1113 	PDEBUG(("%s", DRIVERNAME(driver)));
1114 
1115 	/* Don't allow invalid pass values. */
1116 	if (pass <= BUS_PASS_ROOT)
1117 		return (EINVAL);
1118 
1119 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1120 	if (!dl)
1121 		return (ENOMEM);
1122 
1123 	/*
1124 	 * Compile the driver's methods. Also increase the reference count
1125 	 * so that the class doesn't get freed when the last instance
1126 	 * goes. This means we can safely use static methods and avoids a
1127 	 * double-free in devclass_delete_driver.
1128 	 */
1129 	kobj_class_compile((kobj_class_t) driver);
1130 
1131 	/*
1132 	 * If the driver has any base classes, make the
1133 	 * devclass inherit from the devclass of the driver's
1134 	 * first base class. This will allow the system to
1135 	 * search for drivers in both devclasses for children
1136 	 * of a device using this driver.
1137 	 */
1138 	if (driver->baseclasses)
1139 		parentname = driver->baseclasses[0]->name;
1140 	else
1141 		parentname = NULL;
1142 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1143 
1144 	dl->driver = driver;
1145 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1146 	driver->refs++;		/* XXX: kobj_mtx */
1147 	dl->pass = pass;
1148 	driver_register_pass(dl);
1149 
1150 	if (device_frozen) {
1151 		dl->flags |= DL_DEFERRED_PROBE;
1152 	} else {
1153 		devclass_driver_added(dc, driver);
1154 	}
1155 	bus_data_generation_update();
1156 	return (0);
1157 }
1158 
1159 /**
1160  * @brief Register that a device driver has been deleted from a devclass
1161  *
1162  * Register that a device driver has been removed from a devclass.
1163  * This is called by devclass_delete_driver to accomplish the
1164  * recursive notification of all the children classes of busclass, as
1165  * well as busclass.  Each layer will attempt to detach the driver
1166  * from any devices that are children of the bus's devclass.  The function
1167  * will return an error if a device fails to detach.
1168  *
1169  * We do a full search here of the devclass list at each iteration
1170  * level to save storing children-lists in the devclass structure.  If
1171  * we ever move beyond a few dozen devices doing this, we may need to
1172  * reevaluate...
1173  *
1174  * @param busclass	the devclass of the parent bus
1175  * @param dc		the devclass of the driver being deleted
1176  * @param driver	the driver being deleted
1177  */
1178 static int
1179 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1180 {
1181 	devclass_t parent;
1182 	device_t dev;
1183 	int error, i;
1184 
1185 	/*
1186 	 * Disassociate from any devices.  We iterate through all the
1187 	 * devices in the devclass of the driver and detach any which are
1188 	 * using the driver and which have a parent in the devclass which
1189 	 * we are deleting from.
1190 	 *
1191 	 * Note that since a driver can be in multiple devclasses, we
1192 	 * should not detach devices which are not children of devices in
1193 	 * the affected devclass.
1194 	 *
1195 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1196 	 * generate later.
1197 	 */
1198 	for (i = 0; i < dc->maxunit; i++) {
1199 		if (dc->devices[i]) {
1200 			dev = dc->devices[i];
1201 			if (dev->driver == driver && dev->parent &&
1202 			    dev->parent->devclass == busclass) {
1203 				if ((error = device_detach(dev)) != 0)
1204 					return (error);
1205 				if (device_frozen) {
1206 					dev->flags &= ~DF_DONENOMATCH;
1207 					dev->flags |= DF_NEEDNOMATCH;
1208 				} else {
1209 					BUS_PROBE_NOMATCH(dev->parent, dev);
1210 					devnomatch(dev);
1211 					dev->flags |= DF_DONENOMATCH;
1212 				}
1213 			}
1214 		}
1215 	}
1216 
1217 	/*
1218 	 * Walk through the children classes.  Since we only keep a
1219 	 * single parent pointer around, we walk the entire list of
1220 	 * devclasses looking for children.  We set the
1221 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1222 	 * the parent, so we only walk the list for those devclasses
1223 	 * that have children.
1224 	 */
1225 	if (!(busclass->flags & DC_HAS_CHILDREN))
1226 		return (0);
1227 	parent = busclass;
1228 	TAILQ_FOREACH(busclass, &devclasses, link) {
1229 		if (busclass->parent == parent) {
1230 			error = devclass_driver_deleted(busclass, dc, driver);
1231 			if (error)
1232 				return (error);
1233 		}
1234 	}
1235 	return (0);
1236 }
1237 
1238 /**
1239  * @brief Delete a device driver from a device class
1240  *
1241  * Delete a device driver from a devclass. This is normally called
1242  * automatically by DRIVER_MODULE().
1243  *
1244  * If the driver is currently attached to any devices,
1245  * devclass_delete_driver() will first attempt to detach from each
1246  * device. If one of the detach calls fails, the driver will not be
1247  * deleted.
1248  *
1249  * @param dc		the devclass to edit
1250  * @param driver	the driver to unregister
1251  */
1252 int
1253 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1254 {
1255 	devclass_t dc = devclass_find(driver->name);
1256 	driverlink_t dl;
1257 	int error;
1258 
1259 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1260 
1261 	if (!dc)
1262 		return (0);
1263 
1264 	/*
1265 	 * Find the link structure in the bus' list of drivers.
1266 	 */
1267 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1268 		if (dl->driver == driver)
1269 			break;
1270 	}
1271 
1272 	if (!dl) {
1273 		PDEBUG(("%s not found in %s list", driver->name,
1274 		    busclass->name));
1275 		return (ENOENT);
1276 	}
1277 
1278 	error = devclass_driver_deleted(busclass, dc, driver);
1279 	if (error != 0)
1280 		return (error);
1281 
1282 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1283 	free(dl, M_BUS);
1284 
1285 	/* XXX: kobj_mtx */
1286 	driver->refs--;
1287 	if (driver->refs == 0)
1288 		kobj_class_free((kobj_class_t) driver);
1289 
1290 	bus_data_generation_update();
1291 	return (0);
1292 }
1293 
1294 /**
1295  * @brief Quiesces a set of device drivers from a device class
1296  *
1297  * Quiesce a device driver from a devclass. This is normally called
1298  * automatically by DRIVER_MODULE().
1299  *
1300  * If the driver is currently attached to any devices,
1301  * devclass_quiesece_driver() will first attempt to quiesce each
1302  * device.
1303  *
1304  * @param dc		the devclass to edit
1305  * @param driver	the driver to unregister
1306  */
1307 static int
1308 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1309 {
1310 	devclass_t dc = devclass_find(driver->name);
1311 	driverlink_t dl;
1312 	device_t dev;
1313 	int i;
1314 	int error;
1315 
1316 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1317 
1318 	if (!dc)
1319 		return (0);
1320 
1321 	/*
1322 	 * Find the link structure in the bus' list of drivers.
1323 	 */
1324 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1325 		if (dl->driver == driver)
1326 			break;
1327 	}
1328 
1329 	if (!dl) {
1330 		PDEBUG(("%s not found in %s list", driver->name,
1331 		    busclass->name));
1332 		return (ENOENT);
1333 	}
1334 
1335 	/*
1336 	 * Quiesce all devices.  We iterate through all the devices in
1337 	 * the devclass of the driver and quiesce any which are using
1338 	 * the driver and which have a parent in the devclass which we
1339 	 * are quiescing.
1340 	 *
1341 	 * Note that since a driver can be in multiple devclasses, we
1342 	 * should not quiesce devices which are not children of
1343 	 * devices in the affected devclass.
1344 	 */
1345 	for (i = 0; i < dc->maxunit; i++) {
1346 		if (dc->devices[i]) {
1347 			dev = dc->devices[i];
1348 			if (dev->driver == driver && dev->parent &&
1349 			    dev->parent->devclass == busclass) {
1350 				if ((error = device_quiesce(dev)) != 0)
1351 					return (error);
1352 			}
1353 		}
1354 	}
1355 
1356 	return (0);
1357 }
1358 
1359 /**
1360  * @internal
1361  */
1362 static driverlink_t
1363 devclass_find_driver_internal(devclass_t dc, const char *classname)
1364 {
1365 	driverlink_t dl;
1366 
1367 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1368 
1369 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1370 		if (!strcmp(dl->driver->name, classname))
1371 			return (dl);
1372 	}
1373 
1374 	PDEBUG(("not found"));
1375 	return (NULL);
1376 }
1377 
1378 /**
1379  * @brief Return the name of the devclass
1380  */
1381 const char *
1382 devclass_get_name(devclass_t dc)
1383 {
1384 	return (dc->name);
1385 }
1386 
1387 /**
1388  * @brief Find a device given a unit number
1389  *
1390  * @param dc		the devclass to search
1391  * @param unit		the unit number to search for
1392  *
1393  * @returns		the device with the given unit number or @c
1394  *			NULL if there is no such device
1395  */
1396 device_t
1397 devclass_get_device(devclass_t dc, int unit)
1398 {
1399 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1400 		return (NULL);
1401 	return (dc->devices[unit]);
1402 }
1403 
1404 /**
1405  * @brief Find the softc field of a device given a unit number
1406  *
1407  * @param dc		the devclass to search
1408  * @param unit		the unit number to search for
1409  *
1410  * @returns		the softc field of the device with the given
1411  *			unit number or @c NULL if there is no such
1412  *			device
1413  */
1414 void *
1415 devclass_get_softc(devclass_t dc, int unit)
1416 {
1417 	device_t dev;
1418 
1419 	dev = devclass_get_device(dc, unit);
1420 	if (!dev)
1421 		return (NULL);
1422 
1423 	return (device_get_softc(dev));
1424 }
1425 
1426 /**
1427  * @brief Get a list of devices in the devclass
1428  *
1429  * An array containing a list of all the devices in the given devclass
1430  * is allocated and returned in @p *devlistp. The number of devices
1431  * in the array is returned in @p *devcountp. The caller should free
1432  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1433  *
1434  * @param dc		the devclass to examine
1435  * @param devlistp	points at location for array pointer return
1436  *			value
1437  * @param devcountp	points at location for array size return value
1438  *
1439  * @retval 0		success
1440  * @retval ENOMEM	the array allocation failed
1441  */
1442 int
1443 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1444 {
1445 	int count, i;
1446 	device_t *list;
1447 
1448 	count = devclass_get_count(dc);
1449 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1450 	if (!list)
1451 		return (ENOMEM);
1452 
1453 	count = 0;
1454 	for (i = 0; i < dc->maxunit; i++) {
1455 		if (dc->devices[i]) {
1456 			list[count] = dc->devices[i];
1457 			count++;
1458 		}
1459 	}
1460 
1461 	*devlistp = list;
1462 	*devcountp = count;
1463 
1464 	return (0);
1465 }
1466 
1467 /**
1468  * @brief Get a list of drivers in the devclass
1469  *
1470  * An array containing a list of pointers to all the drivers in the
1471  * given devclass is allocated and returned in @p *listp.  The number
1472  * of drivers in the array is returned in @p *countp. The caller should
1473  * free the array using @c free(p, M_TEMP).
1474  *
1475  * @param dc		the devclass to examine
1476  * @param listp		gives location for array pointer return value
1477  * @param countp	gives location for number of array elements
1478  *			return value
1479  *
1480  * @retval 0		success
1481  * @retval ENOMEM	the array allocation failed
1482  */
1483 int
1484 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1485 {
1486 	driverlink_t dl;
1487 	driver_t **list;
1488 	int count;
1489 
1490 	count = 0;
1491 	TAILQ_FOREACH(dl, &dc->drivers, link)
1492 		count++;
1493 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1494 	if (list == NULL)
1495 		return (ENOMEM);
1496 
1497 	count = 0;
1498 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1499 		list[count] = dl->driver;
1500 		count++;
1501 	}
1502 	*listp = list;
1503 	*countp = count;
1504 
1505 	return (0);
1506 }
1507 
1508 /**
1509  * @brief Get the number of devices in a devclass
1510  *
1511  * @param dc		the devclass to examine
1512  */
1513 int
1514 devclass_get_count(devclass_t dc)
1515 {
1516 	int count, i;
1517 
1518 	count = 0;
1519 	for (i = 0; i < dc->maxunit; i++)
1520 		if (dc->devices[i])
1521 			count++;
1522 	return (count);
1523 }
1524 
1525 /**
1526  * @brief Get the maximum unit number used in a devclass
1527  *
1528  * Note that this is one greater than the highest currently-allocated
1529  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1530  * that not even the devclass has been allocated yet.
1531  *
1532  * @param dc		the devclass to examine
1533  */
1534 int
1535 devclass_get_maxunit(devclass_t dc)
1536 {
1537 	if (dc == NULL)
1538 		return (-1);
1539 	return (dc->maxunit);
1540 }
1541 
1542 /**
1543  * @brief Find a free unit number in a devclass
1544  *
1545  * This function searches for the first unused unit number greater
1546  * that or equal to @p unit.
1547  *
1548  * @param dc		the devclass to examine
1549  * @param unit		the first unit number to check
1550  */
1551 int
1552 devclass_find_free_unit(devclass_t dc, int unit)
1553 {
1554 	if (dc == NULL)
1555 		return (unit);
1556 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1557 		unit++;
1558 	return (unit);
1559 }
1560 
1561 /**
1562  * @brief Set the parent of a devclass
1563  *
1564  * The parent class is normally initialised automatically by
1565  * DRIVER_MODULE().
1566  *
1567  * @param dc		the devclass to edit
1568  * @param pdc		the new parent devclass
1569  */
1570 void
1571 devclass_set_parent(devclass_t dc, devclass_t pdc)
1572 {
1573 	dc->parent = pdc;
1574 }
1575 
1576 /**
1577  * @brief Get the parent of a devclass
1578  *
1579  * @param dc		the devclass to examine
1580  */
1581 devclass_t
1582 devclass_get_parent(devclass_t dc)
1583 {
1584 	return (dc->parent);
1585 }
1586 
1587 struct sysctl_ctx_list *
1588 devclass_get_sysctl_ctx(devclass_t dc)
1589 {
1590 	return (&dc->sysctl_ctx);
1591 }
1592 
1593 struct sysctl_oid *
1594 devclass_get_sysctl_tree(devclass_t dc)
1595 {
1596 	return (dc->sysctl_tree);
1597 }
1598 
1599 /**
1600  * @internal
1601  * @brief Allocate a unit number
1602  *
1603  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1604  * will do). The allocated unit number is returned in @p *unitp.
1605 
1606  * @param dc		the devclass to allocate from
1607  * @param unitp		points at the location for the allocated unit
1608  *			number
1609  *
1610  * @retval 0		success
1611  * @retval EEXIST	the requested unit number is already allocated
1612  * @retval ENOMEM	memory allocation failure
1613  */
1614 static int
1615 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1616 {
1617 	const char *s;
1618 	int unit = *unitp;
1619 
1620 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1621 
1622 	/* Ask the parent bus if it wants to wire this device. */
1623 	if (unit == -1)
1624 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1625 		    &unit);
1626 
1627 	/* If we were given a wired unit number, check for existing device */
1628 	/* XXX imp XXX */
1629 	if (unit != -1) {
1630 		if (unit >= 0 && unit < dc->maxunit &&
1631 		    dc->devices[unit] != NULL) {
1632 			if (bootverbose)
1633 				printf("%s: %s%d already exists; skipping it\n",
1634 				    dc->name, dc->name, *unitp);
1635 			return (EEXIST);
1636 		}
1637 	} else {
1638 		/* Unwired device, find the next available slot for it */
1639 		unit = 0;
1640 		for (unit = 0;; unit++) {
1641 			/* If this device slot is already in use, skip it. */
1642 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1643 				continue;
1644 
1645 			/* If there is an "at" hint for a unit then skip it. */
1646 			if (resource_string_value(dc->name, unit, "at", &s) ==
1647 			    0)
1648 				continue;
1649 
1650 			break;
1651 		}
1652 	}
1653 
1654 	/*
1655 	 * We've selected a unit beyond the length of the table, so let's
1656 	 * extend the table to make room for all units up to and including
1657 	 * this one.
1658 	 */
1659 	if (unit >= dc->maxunit) {
1660 		device_t *newlist, *oldlist;
1661 		int newsize;
1662 
1663 		oldlist = dc->devices;
1664 		newsize = roundup((unit + 1),
1665 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1666 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1667 		if (!newlist)
1668 			return (ENOMEM);
1669 		if (oldlist != NULL)
1670 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1671 		bzero(newlist + dc->maxunit,
1672 		    sizeof(device_t) * (newsize - dc->maxunit));
1673 		dc->devices = newlist;
1674 		dc->maxunit = newsize;
1675 		if (oldlist != NULL)
1676 			free(oldlist, M_BUS);
1677 	}
1678 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1679 
1680 	*unitp = unit;
1681 	return (0);
1682 }
1683 
1684 /**
1685  * @internal
1686  * @brief Add a device to a devclass
1687  *
1688  * A unit number is allocated for the device (using the device's
1689  * preferred unit number if any) and the device is registered in the
1690  * devclass. This allows the device to be looked up by its unit
1691  * number, e.g. by decoding a dev_t minor number.
1692  *
1693  * @param dc		the devclass to add to
1694  * @param dev		the device to add
1695  *
1696  * @retval 0		success
1697  * @retval EEXIST	the requested unit number is already allocated
1698  * @retval ENOMEM	memory allocation failure
1699  */
1700 static int
1701 devclass_add_device(devclass_t dc, device_t dev)
1702 {
1703 	int buflen, error;
1704 
1705 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1706 
1707 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1708 	if (buflen < 0)
1709 		return (ENOMEM);
1710 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1711 	if (!dev->nameunit)
1712 		return (ENOMEM);
1713 
1714 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1715 		free(dev->nameunit, M_BUS);
1716 		dev->nameunit = NULL;
1717 		return (error);
1718 	}
1719 	dc->devices[dev->unit] = dev;
1720 	dev->devclass = dc;
1721 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1722 
1723 	return (0);
1724 }
1725 
1726 /**
1727  * @internal
1728  * @brief Delete a device from a devclass
1729  *
1730  * The device is removed from the devclass's device list and its unit
1731  * number is freed.
1732 
1733  * @param dc		the devclass to delete from
1734  * @param dev		the device to delete
1735  *
1736  * @retval 0		success
1737  */
1738 static int
1739 devclass_delete_device(devclass_t dc, device_t dev)
1740 {
1741 	if (!dc || !dev)
1742 		return (0);
1743 
1744 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1745 
1746 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1747 		panic("devclass_delete_device: inconsistent device class");
1748 	dc->devices[dev->unit] = NULL;
1749 	if (dev->flags & DF_WILDCARD)
1750 		dev->unit = -1;
1751 	dev->devclass = NULL;
1752 	free(dev->nameunit, M_BUS);
1753 	dev->nameunit = NULL;
1754 
1755 	return (0);
1756 }
1757 
1758 /**
1759  * @internal
1760  * @brief Make a new device and add it as a child of @p parent
1761  *
1762  * @param parent	the parent of the new device
1763  * @param name		the devclass name of the new device or @c NULL
1764  *			to leave the devclass unspecified
1765  * @parem unit		the unit number of the new device of @c -1 to
1766  *			leave the unit number unspecified
1767  *
1768  * @returns the new device
1769  */
1770 static device_t
1771 make_device(device_t parent, const char *name, int unit)
1772 {
1773 	device_t dev;
1774 	devclass_t dc;
1775 
1776 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1777 
1778 	if (name) {
1779 		dc = devclass_find_internal(name, NULL, TRUE);
1780 		if (!dc) {
1781 			printf("make_device: can't find device class %s\n",
1782 			    name);
1783 			return (NULL);
1784 		}
1785 	} else {
1786 		dc = NULL;
1787 	}
1788 
1789 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1790 	if (!dev)
1791 		return (NULL);
1792 
1793 	dev->parent = parent;
1794 	TAILQ_INIT(&dev->children);
1795 	kobj_init((kobj_t) dev, &null_class);
1796 	dev->driver = NULL;
1797 	dev->devclass = NULL;
1798 	dev->unit = unit;
1799 	dev->nameunit = NULL;
1800 	dev->desc = NULL;
1801 	dev->busy = 0;
1802 	dev->devflags = 0;
1803 	dev->flags = DF_ENABLED;
1804 	dev->order = 0;
1805 	if (unit == -1)
1806 		dev->flags |= DF_WILDCARD;
1807 	if (name) {
1808 		dev->flags |= DF_FIXEDCLASS;
1809 		if (devclass_add_device(dc, dev)) {
1810 			kobj_delete((kobj_t) dev, M_BUS);
1811 			return (NULL);
1812 		}
1813 	}
1814 	if (parent != NULL && device_has_quiet_children(parent))
1815 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1816 	dev->ivars = NULL;
1817 	dev->softc = NULL;
1818 
1819 	dev->state = DS_NOTPRESENT;
1820 
1821 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1822 	bus_data_generation_update();
1823 
1824 	return (dev);
1825 }
1826 
1827 /**
1828  * @internal
1829  * @brief Print a description of a device.
1830  */
1831 static int
1832 device_print_child(device_t dev, device_t child)
1833 {
1834 	int retval = 0;
1835 
1836 	if (device_is_alive(child))
1837 		retval += BUS_PRINT_CHILD(dev, child);
1838 	else
1839 		retval += device_printf(child, " not found\n");
1840 
1841 	return (retval);
1842 }
1843 
1844 /**
1845  * @brief Create a new device
1846  *
1847  * This creates a new device and adds it as a child of an existing
1848  * parent device. The new device will be added after the last existing
1849  * child with order zero.
1850  *
1851  * @param dev		the device which will be the parent of the
1852  *			new child device
1853  * @param name		devclass name for new device or @c NULL if not
1854  *			specified
1855  * @param unit		unit number for new device or @c -1 if not
1856  *			specified
1857  *
1858  * @returns		the new device
1859  */
1860 device_t
1861 device_add_child(device_t dev, const char *name, int unit)
1862 {
1863 	return (device_add_child_ordered(dev, 0, name, unit));
1864 }
1865 
1866 /**
1867  * @brief Create a new device
1868  *
1869  * This creates a new device and adds it as a child of an existing
1870  * parent device. The new device will be added after the last existing
1871  * child with the same order.
1872  *
1873  * @param dev		the device which will be the parent of the
1874  *			new child device
1875  * @param order		a value which is used to partially sort the
1876  *			children of @p dev - devices created using
1877  *			lower values of @p order appear first in @p
1878  *			dev's list of children
1879  * @param name		devclass name for new device or @c NULL if not
1880  *			specified
1881  * @param unit		unit number for new device or @c -1 if not
1882  *			specified
1883  *
1884  * @returns		the new device
1885  */
1886 device_t
1887 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1888 {
1889 	device_t child;
1890 	device_t place;
1891 
1892 	PDEBUG(("%s at %s with order %u as unit %d",
1893 	    name, DEVICENAME(dev), order, unit));
1894 	KASSERT(name != NULL || unit == -1,
1895 	    ("child device with wildcard name and specific unit number"));
1896 
1897 	child = make_device(dev, name, unit);
1898 	if (child == NULL)
1899 		return (child);
1900 	child->order = order;
1901 
1902 	TAILQ_FOREACH(place, &dev->children, link) {
1903 		if (place->order > order)
1904 			break;
1905 	}
1906 
1907 	if (place) {
1908 		/*
1909 		 * The device 'place' is the first device whose order is
1910 		 * greater than the new child.
1911 		 */
1912 		TAILQ_INSERT_BEFORE(place, child, link);
1913 	} else {
1914 		/*
1915 		 * The new child's order is greater or equal to the order of
1916 		 * any existing device. Add the child to the tail of the list.
1917 		 */
1918 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1919 	}
1920 
1921 	bus_data_generation_update();
1922 	return (child);
1923 }
1924 
1925 /**
1926  * @brief Delete a device
1927  *
1928  * This function deletes a device along with all of its children. If
1929  * the device currently has a driver attached to it, the device is
1930  * detached first using device_detach().
1931  *
1932  * @param dev		the parent device
1933  * @param child		the device to delete
1934  *
1935  * @retval 0		success
1936  * @retval non-zero	a unit error code describing the error
1937  */
1938 int
1939 device_delete_child(device_t dev, device_t child)
1940 {
1941 	int error;
1942 	device_t grandchild;
1943 
1944 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1945 
1946 	/* detach parent before deleting children, if any */
1947 	if ((error = device_detach(child)) != 0)
1948 		return (error);
1949 
1950 	/* remove children second */
1951 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1952 		error = device_delete_child(child, grandchild);
1953 		if (error)
1954 			return (error);
1955 	}
1956 
1957 	if (child->devclass)
1958 		devclass_delete_device(child->devclass, child);
1959 	if (child->parent)
1960 		BUS_CHILD_DELETED(dev, child);
1961 	TAILQ_REMOVE(&dev->children, child, link);
1962 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1963 	kobj_delete((kobj_t) child, M_BUS);
1964 
1965 	bus_data_generation_update();
1966 	return (0);
1967 }
1968 
1969 /**
1970  * @brief Delete all children devices of the given device, if any.
1971  *
1972  * This function deletes all children devices of the given device, if
1973  * any, using the device_delete_child() function for each device it
1974  * finds. If a child device cannot be deleted, this function will
1975  * return an error code.
1976  *
1977  * @param dev		the parent device
1978  *
1979  * @retval 0		success
1980  * @retval non-zero	a device would not detach
1981  */
1982 int
1983 device_delete_children(device_t dev)
1984 {
1985 	device_t child;
1986 	int error;
1987 
1988 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
1989 
1990 	error = 0;
1991 
1992 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
1993 		error = device_delete_child(dev, child);
1994 		if (error) {
1995 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
1996 			break;
1997 		}
1998 	}
1999 	return (error);
2000 }
2001 
2002 /**
2003  * @brief Find a device given a unit number
2004  *
2005  * This is similar to devclass_get_devices() but only searches for
2006  * devices which have @p dev as a parent.
2007  *
2008  * @param dev		the parent device to search
2009  * @param unit		the unit number to search for.  If the unit is -1,
2010  *			return the first child of @p dev which has name
2011  *			@p classname (that is, the one with the lowest unit.)
2012  *
2013  * @returns		the device with the given unit number or @c
2014  *			NULL if there is no such device
2015  */
2016 device_t
2017 device_find_child(device_t dev, const char *classname, int unit)
2018 {
2019 	devclass_t dc;
2020 	device_t child;
2021 
2022 	dc = devclass_find(classname);
2023 	if (!dc)
2024 		return (NULL);
2025 
2026 	if (unit != -1) {
2027 		child = devclass_get_device(dc, unit);
2028 		if (child && child->parent == dev)
2029 			return (child);
2030 	} else {
2031 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2032 			child = devclass_get_device(dc, unit);
2033 			if (child && child->parent == dev)
2034 				return (child);
2035 		}
2036 	}
2037 	return (NULL);
2038 }
2039 
2040 /**
2041  * @internal
2042  */
2043 static driverlink_t
2044 first_matching_driver(devclass_t dc, device_t dev)
2045 {
2046 	if (dev->devclass)
2047 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2048 	return (TAILQ_FIRST(&dc->drivers));
2049 }
2050 
2051 /**
2052  * @internal
2053  */
2054 static driverlink_t
2055 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2056 {
2057 	if (dev->devclass) {
2058 		driverlink_t dl;
2059 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2060 			if (!strcmp(dev->devclass->name, dl->driver->name))
2061 				return (dl);
2062 		return (NULL);
2063 	}
2064 	return (TAILQ_NEXT(last, link));
2065 }
2066 
2067 /**
2068  * @internal
2069  */
2070 int
2071 device_probe_child(device_t dev, device_t child)
2072 {
2073 	devclass_t dc;
2074 	driverlink_t best = NULL;
2075 	driverlink_t dl;
2076 	int result, pri = 0;
2077 	/* We should preserve the devclass (or lack of) set by the bus. */
2078 	int hasclass = (child->devclass != NULL);
2079 
2080 	GIANT_REQUIRED;
2081 
2082 	dc = dev->devclass;
2083 	if (!dc)
2084 		panic("device_probe_child: parent device has no devclass");
2085 
2086 	/*
2087 	 * If the state is already probed, then return.
2088 	 */
2089 	if (child->state == DS_ALIVE)
2090 		return (0);
2091 
2092 	for (; dc; dc = dc->parent) {
2093 		for (dl = first_matching_driver(dc, child);
2094 		     dl;
2095 		     dl = next_matching_driver(dc, child, dl)) {
2096 			/* If this driver's pass is too high, then ignore it. */
2097 			if (dl->pass > bus_current_pass)
2098 				continue;
2099 
2100 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2101 			result = device_set_driver(child, dl->driver);
2102 			if (result == ENOMEM)
2103 				return (result);
2104 			else if (result != 0)
2105 				continue;
2106 			if (!hasclass) {
2107 				if (device_set_devclass(child,
2108 				    dl->driver->name) != 0) {
2109 					char const * devname =
2110 					    device_get_name(child);
2111 					if (devname == NULL)
2112 						devname = "(unknown)";
2113 					printf("driver bug: Unable to set "
2114 					    "devclass (class: %s "
2115 					    "devname: %s)\n",
2116 					    dl->driver->name,
2117 					    devname);
2118 					(void)device_set_driver(child, NULL);
2119 					continue;
2120 				}
2121 			}
2122 
2123 			/* Fetch any flags for the device before probing. */
2124 			resource_int_value(dl->driver->name, child->unit,
2125 			    "flags", &child->devflags);
2126 
2127 			result = DEVICE_PROBE(child);
2128 
2129 			/*
2130 			 * If the driver returns SUCCESS, there can be
2131 			 * no higher match for this device.
2132 			 */
2133 			if (result == 0) {
2134 				best = dl;
2135 				pri = 0;
2136 				break;
2137 			}
2138 
2139 			/* Reset flags and devclass before the next probe. */
2140 			child->devflags = 0;
2141 			if (!hasclass)
2142 				(void)device_set_devclass(child, NULL);
2143 
2144 			/*
2145 			 * Reset DF_QUIET in case this driver doesn't
2146 			 * end up as the best driver.
2147 			 */
2148 			device_verbose(child);
2149 
2150 			/*
2151 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2152 			 * only match on devices whose driver was explicitly
2153 			 * specified.
2154 			 */
2155 			if (result <= BUS_PROBE_NOWILDCARD &&
2156 			    !(child->flags & DF_FIXEDCLASS)) {
2157 				result = ENXIO;
2158 			}
2159 
2160 			/*
2161 			 * The driver returned an error so it
2162 			 * certainly doesn't match.
2163 			 */
2164 			if (result > 0) {
2165 				(void)device_set_driver(child, NULL);
2166 				continue;
2167 			}
2168 
2169 			/*
2170 			 * A priority lower than SUCCESS, remember the
2171 			 * best matching driver. Initialise the value
2172 			 * of pri for the first match.
2173 			 */
2174 			if (best == NULL || result > pri) {
2175 				best = dl;
2176 				pri = result;
2177 				continue;
2178 			}
2179 		}
2180 		/*
2181 		 * If we have an unambiguous match in this devclass,
2182 		 * don't look in the parent.
2183 		 */
2184 		if (best && pri == 0)
2185 			break;
2186 	}
2187 
2188 	if (best == NULL)
2189 		return (ENXIO);
2190 
2191 	/*
2192 	 * If we found a driver, change state and initialise the devclass.
2193 	 */
2194 	if (pri < 0) {
2195 		/* Set the winning driver, devclass, and flags. */
2196 		result = device_set_driver(child, best->driver);
2197 		if (result != 0)
2198 			return (result);
2199 		if (!child->devclass) {
2200 			result = device_set_devclass(child, best->driver->name);
2201 			if (result != 0) {
2202 				(void)device_set_driver(child, NULL);
2203 				return (result);
2204 			}
2205 		}
2206 		resource_int_value(best->driver->name, child->unit,
2207 		    "flags", &child->devflags);
2208 
2209 		/*
2210 		 * A bit bogus. Call the probe method again to make sure
2211 		 * that we have the right description.
2212 		 */
2213 		result = DEVICE_PROBE(child);
2214 		if (result > 0) {
2215 			if (!hasclass)
2216 				(void)device_set_devclass(child, NULL);
2217 			(void)device_set_driver(child, NULL);
2218 			return (result);
2219 		}
2220 	}
2221 
2222 	child->state = DS_ALIVE;
2223 	bus_data_generation_update();
2224 	return (0);
2225 }
2226 
2227 /**
2228  * @brief Return the parent of a device
2229  */
2230 device_t
2231 device_get_parent(device_t dev)
2232 {
2233 	return (dev->parent);
2234 }
2235 
2236 /**
2237  * @brief Get a list of children of a device
2238  *
2239  * An array containing a list of all the children of the given device
2240  * is allocated and returned in @p *devlistp. The number of devices
2241  * in the array is returned in @p *devcountp. The caller should free
2242  * the array using @c free(p, M_TEMP).
2243  *
2244  * @param dev		the device to examine
2245  * @param devlistp	points at location for array pointer return
2246  *			value
2247  * @param devcountp	points at location for array size return value
2248  *
2249  * @retval 0		success
2250  * @retval ENOMEM	the array allocation failed
2251  */
2252 int
2253 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2254 {
2255 	int count;
2256 	device_t child;
2257 	device_t *list;
2258 
2259 	count = 0;
2260 	TAILQ_FOREACH(child, &dev->children, link) {
2261 		count++;
2262 	}
2263 	if (count == 0) {
2264 		*devlistp = NULL;
2265 		*devcountp = 0;
2266 		return (0);
2267 	}
2268 
2269 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2270 	if (!list)
2271 		return (ENOMEM);
2272 
2273 	count = 0;
2274 	TAILQ_FOREACH(child, &dev->children, link) {
2275 		list[count] = child;
2276 		count++;
2277 	}
2278 
2279 	*devlistp = list;
2280 	*devcountp = count;
2281 
2282 	return (0);
2283 }
2284 
2285 /**
2286  * @brief Return the current driver for the device or @c NULL if there
2287  * is no driver currently attached
2288  */
2289 driver_t *
2290 device_get_driver(device_t dev)
2291 {
2292 	return (dev->driver);
2293 }
2294 
2295 /**
2296  * @brief Return the current devclass for the device or @c NULL if
2297  * there is none.
2298  */
2299 devclass_t
2300 device_get_devclass(device_t dev)
2301 {
2302 	return (dev->devclass);
2303 }
2304 
2305 /**
2306  * @brief Return the name of the device's devclass or @c NULL if there
2307  * is none.
2308  */
2309 const char *
2310 device_get_name(device_t dev)
2311 {
2312 	if (dev != NULL && dev->devclass)
2313 		return (devclass_get_name(dev->devclass));
2314 	return (NULL);
2315 }
2316 
2317 /**
2318  * @brief Return a string containing the device's devclass name
2319  * followed by an ascii representation of the device's unit number
2320  * (e.g. @c "foo2").
2321  */
2322 const char *
2323 device_get_nameunit(device_t dev)
2324 {
2325 	return (dev->nameunit);
2326 }
2327 
2328 /**
2329  * @brief Return the device's unit number.
2330  */
2331 int
2332 device_get_unit(device_t dev)
2333 {
2334 	return (dev->unit);
2335 }
2336 
2337 /**
2338  * @brief Return the device's description string
2339  */
2340 const char *
2341 device_get_desc(device_t dev)
2342 {
2343 	return (dev->desc);
2344 }
2345 
2346 /**
2347  * @brief Return the device's flags
2348  */
2349 uint32_t
2350 device_get_flags(device_t dev)
2351 {
2352 	return (dev->devflags);
2353 }
2354 
2355 struct sysctl_ctx_list *
2356 device_get_sysctl_ctx(device_t dev)
2357 {
2358 	return (&dev->sysctl_ctx);
2359 }
2360 
2361 struct sysctl_oid *
2362 device_get_sysctl_tree(device_t dev)
2363 {
2364 	return (dev->sysctl_tree);
2365 }
2366 
2367 /**
2368  * @brief Print the name of the device followed by a colon and a space
2369  *
2370  * @returns the number of characters printed
2371  */
2372 int
2373 device_print_prettyname(device_t dev)
2374 {
2375 	const char *name = device_get_name(dev);
2376 
2377 	if (name == NULL)
2378 		return (printf("unknown: "));
2379 	return (printf("%s%d: ", name, device_get_unit(dev)));
2380 }
2381 
2382 /**
2383  * @brief Print the name of the device followed by a colon, a space
2384  * and the result of calling vprintf() with the value of @p fmt and
2385  * the following arguments.
2386  *
2387  * @returns the number of characters printed
2388  */
2389 int
2390 device_printf(device_t dev, const char * fmt, ...)
2391 {
2392 	char buf[128];
2393 	struct sbuf sb;
2394 	const char *name;
2395 	va_list ap;
2396 	size_t retval;
2397 
2398 	retval = 0;
2399 
2400 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2401 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2402 
2403 	name = device_get_name(dev);
2404 
2405 	if (name == NULL)
2406 		sbuf_cat(&sb, "unknown: ");
2407 	else
2408 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2409 
2410 	va_start(ap, fmt);
2411 	sbuf_vprintf(&sb, fmt, ap);
2412 	va_end(ap);
2413 
2414 	sbuf_finish(&sb);
2415 	sbuf_delete(&sb);
2416 
2417 	return (retval);
2418 }
2419 
2420 /**
2421  * @brief Print the name of the device followed by a colon, a space
2422  * and the result of calling log() with the value of @p fmt and
2423  * the following arguments.
2424  *
2425  * @returns the number of characters printed
2426  */
2427 int
2428 device_log(device_t dev, int pri, const char * fmt, ...)
2429 {
2430 	char buf[128];
2431 	struct sbuf sb;
2432 	const char *name;
2433 	va_list ap;
2434 	size_t retval;
2435 
2436 	retval = 0;
2437 
2438 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2439 
2440 	name = device_get_name(dev);
2441 
2442 	if (name == NULL)
2443 		sbuf_cat(&sb, "unknown: ");
2444 	else
2445 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2446 
2447 	va_start(ap, fmt);
2448 	sbuf_vprintf(&sb, fmt, ap);
2449 	va_end(ap);
2450 
2451 	sbuf_finish(&sb);
2452 
2453 	log(pri, "%.*s", (int) sbuf_len(&sb), sbuf_data(&sb));
2454 	retval = sbuf_len(&sb);
2455 
2456 	sbuf_delete(&sb);
2457 
2458 	return (retval);
2459 }
2460 
2461 /**
2462  * @internal
2463  */
2464 static void
2465 device_set_desc_internal(device_t dev, const char* desc, int copy)
2466 {
2467 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2468 		free(dev->desc, M_BUS);
2469 		dev->flags &= ~DF_DESCMALLOCED;
2470 		dev->desc = NULL;
2471 	}
2472 
2473 	if (copy && desc) {
2474 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2475 		if (dev->desc) {
2476 			strcpy(dev->desc, desc);
2477 			dev->flags |= DF_DESCMALLOCED;
2478 		}
2479 	} else {
2480 		/* Avoid a -Wcast-qual warning */
2481 		dev->desc = (char *)(uintptr_t) desc;
2482 	}
2483 
2484 	bus_data_generation_update();
2485 }
2486 
2487 /**
2488  * @brief Set the device's description
2489  *
2490  * The value of @c desc should be a string constant that will not
2491  * change (at least until the description is changed in a subsequent
2492  * call to device_set_desc() or device_set_desc_copy()).
2493  */
2494 void
2495 device_set_desc(device_t dev, const char* desc)
2496 {
2497 	device_set_desc_internal(dev, desc, FALSE);
2498 }
2499 
2500 /**
2501  * @brief Set the device's description
2502  *
2503  * The string pointed to by @c desc is copied. Use this function if
2504  * the device description is generated, (e.g. with sprintf()).
2505  */
2506 void
2507 device_set_desc_copy(device_t dev, const char* desc)
2508 {
2509 	device_set_desc_internal(dev, desc, TRUE);
2510 }
2511 
2512 /**
2513  * @brief Set the device's flags
2514  */
2515 void
2516 device_set_flags(device_t dev, uint32_t flags)
2517 {
2518 	dev->devflags = flags;
2519 }
2520 
2521 /**
2522  * @brief Return the device's softc field
2523  *
2524  * The softc is allocated and zeroed when a driver is attached, based
2525  * on the size field of the driver.
2526  */
2527 void *
2528 device_get_softc(device_t dev)
2529 {
2530 	return (dev->softc);
2531 }
2532 
2533 /**
2534  * @brief Set the device's softc field
2535  *
2536  * Most drivers do not need to use this since the softc is allocated
2537  * automatically when the driver is attached.
2538  */
2539 void
2540 device_set_softc(device_t dev, void *softc)
2541 {
2542 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2543 		free(dev->softc, M_BUS_SC);
2544 	dev->softc = softc;
2545 	if (dev->softc)
2546 		dev->flags |= DF_EXTERNALSOFTC;
2547 	else
2548 		dev->flags &= ~DF_EXTERNALSOFTC;
2549 }
2550 
2551 /**
2552  * @brief Free claimed softc
2553  *
2554  * Most drivers do not need to use this since the softc is freed
2555  * automatically when the driver is detached.
2556  */
2557 void
2558 device_free_softc(void *softc)
2559 {
2560 	free(softc, M_BUS_SC);
2561 }
2562 
2563 /**
2564  * @brief Claim softc
2565  *
2566  * This function can be used to let the driver free the automatically
2567  * allocated softc using "device_free_softc()". This function is
2568  * useful when the driver is refcounting the softc and the softc
2569  * cannot be freed when the "device_detach" method is called.
2570  */
2571 void
2572 device_claim_softc(device_t dev)
2573 {
2574 	if (dev->softc)
2575 		dev->flags |= DF_EXTERNALSOFTC;
2576 	else
2577 		dev->flags &= ~DF_EXTERNALSOFTC;
2578 }
2579 
2580 /**
2581  * @brief Get the device's ivars field
2582  *
2583  * The ivars field is used by the parent device to store per-device
2584  * state (e.g. the physical location of the device or a list of
2585  * resources).
2586  */
2587 void *
2588 device_get_ivars(device_t dev)
2589 {
2590 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2591 	return (dev->ivars);
2592 }
2593 
2594 /**
2595  * @brief Set the device's ivars field
2596  */
2597 void
2598 device_set_ivars(device_t dev, void * ivars)
2599 {
2600 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2601 	dev->ivars = ivars;
2602 }
2603 
2604 /**
2605  * @brief Return the device's state
2606  */
2607 device_state_t
2608 device_get_state(device_t dev)
2609 {
2610 	return (dev->state);
2611 }
2612 
2613 /**
2614  * @brief Set the DF_ENABLED flag for the device
2615  */
2616 void
2617 device_enable(device_t dev)
2618 {
2619 	dev->flags |= DF_ENABLED;
2620 }
2621 
2622 /**
2623  * @brief Clear the DF_ENABLED flag for the device
2624  */
2625 void
2626 device_disable(device_t dev)
2627 {
2628 	dev->flags &= ~DF_ENABLED;
2629 }
2630 
2631 /**
2632  * @brief Increment the busy counter for the device
2633  */
2634 void
2635 device_busy(device_t dev)
2636 {
2637 	if (dev->state < DS_ATTACHING)
2638 		panic("device_busy: called for unattached device");
2639 	if (dev->busy == 0 && dev->parent)
2640 		device_busy(dev->parent);
2641 	dev->busy++;
2642 	if (dev->state == DS_ATTACHED)
2643 		dev->state = DS_BUSY;
2644 }
2645 
2646 /**
2647  * @brief Decrement the busy counter for the device
2648  */
2649 void
2650 device_unbusy(device_t dev)
2651 {
2652 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2653 	    dev->state != DS_ATTACHING)
2654 		panic("device_unbusy: called for non-busy device %s",
2655 		    device_get_nameunit(dev));
2656 	dev->busy--;
2657 	if (dev->busy == 0) {
2658 		if (dev->parent)
2659 			device_unbusy(dev->parent);
2660 		if (dev->state == DS_BUSY)
2661 			dev->state = DS_ATTACHED;
2662 	}
2663 }
2664 
2665 /**
2666  * @brief Set the DF_QUIET flag for the device
2667  */
2668 void
2669 device_quiet(device_t dev)
2670 {
2671 	dev->flags |= DF_QUIET;
2672 }
2673 
2674 /**
2675  * @brief Set the DF_QUIET_CHILDREN flag for the device
2676  */
2677 void
2678 device_quiet_children(device_t dev)
2679 {
2680 	dev->flags |= DF_QUIET_CHILDREN;
2681 }
2682 
2683 /**
2684  * @brief Clear the DF_QUIET flag for the device
2685  */
2686 void
2687 device_verbose(device_t dev)
2688 {
2689 	dev->flags &= ~DF_QUIET;
2690 }
2691 
2692 ssize_t
2693 device_get_property(device_t dev, const char *prop, void *val, size_t sz)
2694 {
2695 	device_t bus = device_get_parent(dev);
2696 
2697 	return (BUS_GET_PROPERTY(bus, dev, prop, val, sz));
2698 }
2699 
2700 bool
2701 device_has_property(device_t dev, const char *prop)
2702 {
2703 	return (device_get_property(dev, prop, NULL, 0) >= 0);
2704 }
2705 
2706 /**
2707  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2708  */
2709 int
2710 device_has_quiet_children(device_t dev)
2711 {
2712 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2713 }
2714 
2715 /**
2716  * @brief Return non-zero if the DF_QUIET flag is set on the device
2717  */
2718 int
2719 device_is_quiet(device_t dev)
2720 {
2721 	return ((dev->flags & DF_QUIET) != 0);
2722 }
2723 
2724 /**
2725  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2726  */
2727 int
2728 device_is_enabled(device_t dev)
2729 {
2730 	return ((dev->flags & DF_ENABLED) != 0);
2731 }
2732 
2733 /**
2734  * @brief Return non-zero if the device was successfully probed
2735  */
2736 int
2737 device_is_alive(device_t dev)
2738 {
2739 	return (dev->state >= DS_ALIVE);
2740 }
2741 
2742 /**
2743  * @brief Return non-zero if the device currently has a driver
2744  * attached to it
2745  */
2746 int
2747 device_is_attached(device_t dev)
2748 {
2749 	return (dev->state >= DS_ATTACHED);
2750 }
2751 
2752 /**
2753  * @brief Return non-zero if the device is currently suspended.
2754  */
2755 int
2756 device_is_suspended(device_t dev)
2757 {
2758 	return ((dev->flags & DF_SUSPENDED) != 0);
2759 }
2760 
2761 /**
2762  * @brief Set the devclass of a device
2763  * @see devclass_add_device().
2764  */
2765 int
2766 device_set_devclass(device_t dev, const char *classname)
2767 {
2768 	devclass_t dc;
2769 	int error;
2770 
2771 	if (!classname) {
2772 		if (dev->devclass)
2773 			devclass_delete_device(dev->devclass, dev);
2774 		return (0);
2775 	}
2776 
2777 	if (dev->devclass) {
2778 		printf("device_set_devclass: device class already set\n");
2779 		return (EINVAL);
2780 	}
2781 
2782 	dc = devclass_find_internal(classname, NULL, TRUE);
2783 	if (!dc)
2784 		return (ENOMEM);
2785 
2786 	error = devclass_add_device(dc, dev);
2787 
2788 	bus_data_generation_update();
2789 	return (error);
2790 }
2791 
2792 /**
2793  * @brief Set the devclass of a device and mark the devclass fixed.
2794  * @see device_set_devclass()
2795  */
2796 int
2797 device_set_devclass_fixed(device_t dev, const char *classname)
2798 {
2799 	int error;
2800 
2801 	if (classname == NULL)
2802 		return (EINVAL);
2803 
2804 	error = device_set_devclass(dev, classname);
2805 	if (error)
2806 		return (error);
2807 	dev->flags |= DF_FIXEDCLASS;
2808 	return (0);
2809 }
2810 
2811 /**
2812  * @brief Query the device to determine if it's of a fixed devclass
2813  * @see device_set_devclass_fixed()
2814  */
2815 bool
2816 device_is_devclass_fixed(device_t dev)
2817 {
2818 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2819 }
2820 
2821 /**
2822  * @brief Set the driver of a device
2823  *
2824  * @retval 0		success
2825  * @retval EBUSY	the device already has a driver attached
2826  * @retval ENOMEM	a memory allocation failure occurred
2827  */
2828 int
2829 device_set_driver(device_t dev, driver_t *driver)
2830 {
2831 	int domain;
2832 	struct domainset *policy;
2833 
2834 	if (dev->state >= DS_ATTACHED)
2835 		return (EBUSY);
2836 
2837 	if (dev->driver == driver)
2838 		return (0);
2839 
2840 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2841 		free(dev->softc, M_BUS_SC);
2842 		dev->softc = NULL;
2843 	}
2844 	device_set_desc(dev, NULL);
2845 	kobj_delete((kobj_t) dev, NULL);
2846 	dev->driver = driver;
2847 	if (driver) {
2848 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2849 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2850 			if (bus_get_domain(dev, &domain) == 0)
2851 				policy = DOMAINSET_PREF(domain);
2852 			else
2853 				policy = DOMAINSET_RR();
2854 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2855 			    policy, M_NOWAIT | M_ZERO);
2856 			if (!dev->softc) {
2857 				kobj_delete((kobj_t) dev, NULL);
2858 				kobj_init((kobj_t) dev, &null_class);
2859 				dev->driver = NULL;
2860 				return (ENOMEM);
2861 			}
2862 		}
2863 	} else {
2864 		kobj_init((kobj_t) dev, &null_class);
2865 	}
2866 
2867 	bus_data_generation_update();
2868 	return (0);
2869 }
2870 
2871 /**
2872  * @brief Probe a device, and return this status.
2873  *
2874  * This function is the core of the device autoconfiguration
2875  * system. Its purpose is to select a suitable driver for a device and
2876  * then call that driver to initialise the hardware appropriately. The
2877  * driver is selected by calling the DEVICE_PROBE() method of a set of
2878  * candidate drivers and then choosing the driver which returned the
2879  * best value. This driver is then attached to the device using
2880  * device_attach().
2881  *
2882  * The set of suitable drivers is taken from the list of drivers in
2883  * the parent device's devclass. If the device was originally created
2884  * with a specific class name (see device_add_child()), only drivers
2885  * with that name are probed, otherwise all drivers in the devclass
2886  * are probed. If no drivers return successful probe values in the
2887  * parent devclass, the search continues in the parent of that
2888  * devclass (see devclass_get_parent()) if any.
2889  *
2890  * @param dev		the device to initialise
2891  *
2892  * @retval 0		success
2893  * @retval ENXIO	no driver was found
2894  * @retval ENOMEM	memory allocation failure
2895  * @retval non-zero	some other unix error code
2896  * @retval -1		Device already attached
2897  */
2898 int
2899 device_probe(device_t dev)
2900 {
2901 	int error;
2902 
2903 	GIANT_REQUIRED;
2904 
2905 	if (dev->state >= DS_ALIVE)
2906 		return (-1);
2907 
2908 	if (!(dev->flags & DF_ENABLED)) {
2909 		if (bootverbose && device_get_name(dev) != NULL) {
2910 			device_print_prettyname(dev);
2911 			printf("not probed (disabled)\n");
2912 		}
2913 		return (-1);
2914 	}
2915 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2916 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2917 		    !(dev->flags & DF_DONENOMATCH)) {
2918 			BUS_PROBE_NOMATCH(dev->parent, dev);
2919 			devnomatch(dev);
2920 			dev->flags |= DF_DONENOMATCH;
2921 		}
2922 		return (error);
2923 	}
2924 	return (0);
2925 }
2926 
2927 /**
2928  * @brief Probe a device and attach a driver if possible
2929  *
2930  * calls device_probe() and attaches if that was successful.
2931  */
2932 int
2933 device_probe_and_attach(device_t dev)
2934 {
2935 	int error;
2936 
2937 	GIANT_REQUIRED;
2938 
2939 	error = device_probe(dev);
2940 	if (error == -1)
2941 		return (0);
2942 	else if (error != 0)
2943 		return (error);
2944 
2945 	CURVNET_SET_QUIET(vnet0);
2946 	error = device_attach(dev);
2947 	CURVNET_RESTORE();
2948 	return error;
2949 }
2950 
2951 /**
2952  * @brief Attach a device driver to a device
2953  *
2954  * This function is a wrapper around the DEVICE_ATTACH() driver
2955  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2956  * device's sysctl tree, optionally prints a description of the device
2957  * and queues a notification event for user-based device management
2958  * services.
2959  *
2960  * Normally this function is only called internally from
2961  * device_probe_and_attach().
2962  *
2963  * @param dev		the device to initialise
2964  *
2965  * @retval 0		success
2966  * @retval ENXIO	no driver was found
2967  * @retval ENOMEM	memory allocation failure
2968  * @retval non-zero	some other unix error code
2969  */
2970 int
2971 device_attach(device_t dev)
2972 {
2973 	uint64_t attachtime;
2974 	uint16_t attachentropy;
2975 	int error;
2976 
2977 	if (resource_disabled(dev->driver->name, dev->unit)) {
2978 		device_disable(dev);
2979 		if (bootverbose)
2980 			 device_printf(dev, "disabled via hints entry\n");
2981 		return (ENXIO);
2982 	}
2983 
2984 	device_sysctl_init(dev);
2985 	if (!device_is_quiet(dev))
2986 		device_print_child(dev->parent, dev);
2987 	attachtime = get_cyclecount();
2988 	dev->state = DS_ATTACHING;
2989 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2990 		printf("device_attach: %s%d attach returned %d\n",
2991 		    dev->driver->name, dev->unit, error);
2992 		if (!(dev->flags & DF_FIXEDCLASS))
2993 			devclass_delete_device(dev->devclass, dev);
2994 		(void)device_set_driver(dev, NULL);
2995 		device_sysctl_fini(dev);
2996 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2997 		dev->state = DS_NOTPRESENT;
2998 		return (error);
2999 	}
3000 	dev->flags |= DF_ATTACHED_ONCE;
3001 	/* We only need the low bits of this time, but ranges from tens to thousands
3002 	 * have been seen, so keep 2 bytes' worth.
3003 	 */
3004 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3005 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3006 	device_sysctl_update(dev);
3007 	if (dev->busy)
3008 		dev->state = DS_BUSY;
3009 	else
3010 		dev->state = DS_ATTACHED;
3011 	dev->flags &= ~DF_DONENOMATCH;
3012 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3013 	devadded(dev);
3014 	return (0);
3015 }
3016 
3017 /**
3018  * @brief Detach a driver from a device
3019  *
3020  * This function is a wrapper around the DEVICE_DETACH() driver
3021  * method. If the call to DEVICE_DETACH() succeeds, it calls
3022  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3023  * notification event for user-based device management services and
3024  * cleans up the device's sysctl tree.
3025  *
3026  * @param dev		the device to un-initialise
3027  *
3028  * @retval 0		success
3029  * @retval ENXIO	no driver was found
3030  * @retval ENOMEM	memory allocation failure
3031  * @retval non-zero	some other unix error code
3032  */
3033 int
3034 device_detach(device_t dev)
3035 {
3036 	int error;
3037 
3038 	GIANT_REQUIRED;
3039 
3040 	PDEBUG(("%s", DEVICENAME(dev)));
3041 	if (dev->state == DS_BUSY)
3042 		return (EBUSY);
3043 	if (dev->state == DS_ATTACHING) {
3044 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3045 		return (EBUSY);
3046 	}
3047 	if (dev->state != DS_ATTACHED)
3048 		return (0);
3049 
3050 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3051 	if ((error = DEVICE_DETACH(dev)) != 0) {
3052 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3053 		    EVHDEV_DETACH_FAILED);
3054 		return (error);
3055 	} else {
3056 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3057 		    EVHDEV_DETACH_COMPLETE);
3058 	}
3059 	devremoved(dev);
3060 	if (!device_is_quiet(dev))
3061 		device_printf(dev, "detached\n");
3062 	if (dev->parent)
3063 		BUS_CHILD_DETACHED(dev->parent, dev);
3064 
3065 	if (!(dev->flags & DF_FIXEDCLASS))
3066 		devclass_delete_device(dev->devclass, dev);
3067 
3068 	device_verbose(dev);
3069 	dev->state = DS_NOTPRESENT;
3070 	(void)device_set_driver(dev, NULL);
3071 	device_sysctl_fini(dev);
3072 
3073 	return (0);
3074 }
3075 
3076 /**
3077  * @brief Tells a driver to quiesce itself.
3078  *
3079  * This function is a wrapper around the DEVICE_QUIESCE() driver
3080  * method. If the call to DEVICE_QUIESCE() succeeds.
3081  *
3082  * @param dev		the device to quiesce
3083  *
3084  * @retval 0		success
3085  * @retval ENXIO	no driver was found
3086  * @retval ENOMEM	memory allocation failure
3087  * @retval non-zero	some other unix error code
3088  */
3089 int
3090 device_quiesce(device_t dev)
3091 {
3092 	PDEBUG(("%s", DEVICENAME(dev)));
3093 	if (dev->state == DS_BUSY)
3094 		return (EBUSY);
3095 	if (dev->state != DS_ATTACHED)
3096 		return (0);
3097 
3098 	return (DEVICE_QUIESCE(dev));
3099 }
3100 
3101 /**
3102  * @brief Notify a device of system shutdown
3103  *
3104  * This function calls the DEVICE_SHUTDOWN() driver method if the
3105  * device currently has an attached driver.
3106  *
3107  * @returns the value returned by DEVICE_SHUTDOWN()
3108  */
3109 int
3110 device_shutdown(device_t dev)
3111 {
3112 	if (dev->state < DS_ATTACHED)
3113 		return (0);
3114 	return (DEVICE_SHUTDOWN(dev));
3115 }
3116 
3117 /**
3118  * @brief Set the unit number of a device
3119  *
3120  * This function can be used to override the unit number used for a
3121  * device (e.g. to wire a device to a pre-configured unit number).
3122  */
3123 int
3124 device_set_unit(device_t dev, int unit)
3125 {
3126 	devclass_t dc;
3127 	int err;
3128 
3129 	if (unit == dev->unit)
3130 		return (0);
3131 	dc = device_get_devclass(dev);
3132 	if (unit < dc->maxunit && dc->devices[unit])
3133 		return (EBUSY);
3134 	err = devclass_delete_device(dc, dev);
3135 	if (err)
3136 		return (err);
3137 	dev->unit = unit;
3138 	err = devclass_add_device(dc, dev);
3139 	if (err)
3140 		return (err);
3141 
3142 	bus_data_generation_update();
3143 	return (0);
3144 }
3145 
3146 /*======================================*/
3147 /*
3148  * Some useful method implementations to make life easier for bus drivers.
3149  */
3150 
3151 void
3152 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3153 {
3154 	bzero(args, sz);
3155 	args->size = sz;
3156 	args->memattr = VM_MEMATTR_DEVICE;
3157 }
3158 
3159 /**
3160  * @brief Initialise a resource list.
3161  *
3162  * @param rl		the resource list to initialise
3163  */
3164 void
3165 resource_list_init(struct resource_list *rl)
3166 {
3167 	STAILQ_INIT(rl);
3168 }
3169 
3170 /**
3171  * @brief Reclaim memory used by a resource list.
3172  *
3173  * This function frees the memory for all resource entries on the list
3174  * (if any).
3175  *
3176  * @param rl		the resource list to free
3177  */
3178 void
3179 resource_list_free(struct resource_list *rl)
3180 {
3181 	struct resource_list_entry *rle;
3182 
3183 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3184 		if (rle->res)
3185 			panic("resource_list_free: resource entry is busy");
3186 		STAILQ_REMOVE_HEAD(rl, link);
3187 		free(rle, M_BUS);
3188 	}
3189 }
3190 
3191 /**
3192  * @brief Add a resource entry.
3193  *
3194  * This function adds a resource entry using the given @p type, @p
3195  * start, @p end and @p count values. A rid value is chosen by
3196  * searching sequentially for the first unused rid starting at zero.
3197  *
3198  * @param rl		the resource list to edit
3199  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3200  * @param start		the start address of the resource
3201  * @param end		the end address of the resource
3202  * @param count		XXX end-start+1
3203  */
3204 int
3205 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3206     rman_res_t end, rman_res_t count)
3207 {
3208 	int rid;
3209 
3210 	rid = 0;
3211 	while (resource_list_find(rl, type, rid) != NULL)
3212 		rid++;
3213 	resource_list_add(rl, type, rid, start, end, count);
3214 	return (rid);
3215 }
3216 
3217 /**
3218  * @brief Add or modify a resource entry.
3219  *
3220  * If an existing entry exists with the same type and rid, it will be
3221  * modified using the given values of @p start, @p end and @p
3222  * count. If no entry exists, a new one will be created using the
3223  * given values.  The resource list entry that matches is then returned.
3224  *
3225  * @param rl		the resource list to edit
3226  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3227  * @param rid		the resource identifier
3228  * @param start		the start address of the resource
3229  * @param end		the end address of the resource
3230  * @param count		XXX end-start+1
3231  */
3232 struct resource_list_entry *
3233 resource_list_add(struct resource_list *rl, int type, int rid,
3234     rman_res_t start, rman_res_t end, rman_res_t count)
3235 {
3236 	struct resource_list_entry *rle;
3237 
3238 	rle = resource_list_find(rl, type, rid);
3239 	if (!rle) {
3240 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3241 		    M_NOWAIT);
3242 		if (!rle)
3243 			panic("resource_list_add: can't record entry");
3244 		STAILQ_INSERT_TAIL(rl, rle, link);
3245 		rle->type = type;
3246 		rle->rid = rid;
3247 		rle->res = NULL;
3248 		rle->flags = 0;
3249 	}
3250 
3251 	if (rle->res)
3252 		panic("resource_list_add: resource entry is busy");
3253 
3254 	rle->start = start;
3255 	rle->end = end;
3256 	rle->count = count;
3257 	return (rle);
3258 }
3259 
3260 /**
3261  * @brief Determine if a resource entry is busy.
3262  *
3263  * Returns true if a resource entry is busy meaning that it has an
3264  * associated resource that is not an unallocated "reserved" resource.
3265  *
3266  * @param rl		the resource list to search
3267  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3268  * @param rid		the resource identifier
3269  *
3270  * @returns Non-zero if the entry is busy, zero otherwise.
3271  */
3272 int
3273 resource_list_busy(struct resource_list *rl, int type, int rid)
3274 {
3275 	struct resource_list_entry *rle;
3276 
3277 	rle = resource_list_find(rl, type, rid);
3278 	if (rle == NULL || rle->res == NULL)
3279 		return (0);
3280 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3281 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3282 		    ("reserved resource is active"));
3283 		return (0);
3284 	}
3285 	return (1);
3286 }
3287 
3288 /**
3289  * @brief Determine if a resource entry is reserved.
3290  *
3291  * Returns true if a resource entry is reserved meaning that it has an
3292  * associated "reserved" resource.  The resource can either be
3293  * allocated or unallocated.
3294  *
3295  * @param rl		the resource list to search
3296  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3297  * @param rid		the resource identifier
3298  *
3299  * @returns Non-zero if the entry is reserved, zero otherwise.
3300  */
3301 int
3302 resource_list_reserved(struct resource_list *rl, int type, int rid)
3303 {
3304 	struct resource_list_entry *rle;
3305 
3306 	rle = resource_list_find(rl, type, rid);
3307 	if (rle != NULL && rle->flags & RLE_RESERVED)
3308 		return (1);
3309 	return (0);
3310 }
3311 
3312 /**
3313  * @brief Find a resource entry by type and rid.
3314  *
3315  * @param rl		the resource list to search
3316  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3317  * @param rid		the resource identifier
3318  *
3319  * @returns the resource entry pointer or NULL if there is no such
3320  * entry.
3321  */
3322 struct resource_list_entry *
3323 resource_list_find(struct resource_list *rl, int type, int rid)
3324 {
3325 	struct resource_list_entry *rle;
3326 
3327 	STAILQ_FOREACH(rle, rl, link) {
3328 		if (rle->type == type && rle->rid == rid)
3329 			return (rle);
3330 	}
3331 	return (NULL);
3332 }
3333 
3334 /**
3335  * @brief Delete a resource entry.
3336  *
3337  * @param rl		the resource list to edit
3338  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3339  * @param rid		the resource identifier
3340  */
3341 void
3342 resource_list_delete(struct resource_list *rl, int type, int rid)
3343 {
3344 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3345 
3346 	if (rle) {
3347 		if (rle->res != NULL)
3348 			panic("resource_list_delete: resource has not been released");
3349 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3350 		free(rle, M_BUS);
3351 	}
3352 }
3353 
3354 /**
3355  * @brief Allocate a reserved resource
3356  *
3357  * This can be used by buses to force the allocation of resources
3358  * that are always active in the system even if they are not allocated
3359  * by a driver (e.g. PCI BARs).  This function is usually called when
3360  * adding a new child to the bus.  The resource is allocated from the
3361  * parent bus when it is reserved.  The resource list entry is marked
3362  * with RLE_RESERVED to note that it is a reserved resource.
3363  *
3364  * Subsequent attempts to allocate the resource with
3365  * resource_list_alloc() will succeed the first time and will set
3366  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3367  * resource that has been allocated is released with
3368  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3369  * the actual resource remains allocated.  The resource can be released to
3370  * the parent bus by calling resource_list_unreserve().
3371  *
3372  * @param rl		the resource list to allocate from
3373  * @param bus		the parent device of @p child
3374  * @param child		the device for which the resource is being reserved
3375  * @param type		the type of resource to allocate
3376  * @param rid		a pointer to the resource identifier
3377  * @param start		hint at the start of the resource range - pass
3378  *			@c 0 for any start address
3379  * @param end		hint at the end of the resource range - pass
3380  *			@c ~0 for any end address
3381  * @param count		hint at the size of range required - pass @c 1
3382  *			for any size
3383  * @param flags		any extra flags to control the resource
3384  *			allocation - see @c RF_XXX flags in
3385  *			<sys/rman.h> for details
3386  *
3387  * @returns		the resource which was allocated or @c NULL if no
3388  *			resource could be allocated
3389  */
3390 struct resource *
3391 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3392     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3393 {
3394 	struct resource_list_entry *rle = NULL;
3395 	int passthrough = (device_get_parent(child) != bus);
3396 	struct resource *r;
3397 
3398 	if (passthrough)
3399 		panic(
3400     "resource_list_reserve() should only be called for direct children");
3401 	if (flags & RF_ACTIVE)
3402 		panic(
3403     "resource_list_reserve() should only reserve inactive resources");
3404 
3405 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3406 	    flags);
3407 	if (r != NULL) {
3408 		rle = resource_list_find(rl, type, *rid);
3409 		rle->flags |= RLE_RESERVED;
3410 	}
3411 	return (r);
3412 }
3413 
3414 /**
3415  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3416  *
3417  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3418  * and passing the allocation up to the parent of @p bus. This assumes
3419  * that the first entry of @c device_get_ivars(child) is a struct
3420  * resource_list. This also handles 'passthrough' allocations where a
3421  * child is a remote descendant of bus by passing the allocation up to
3422  * the parent of bus.
3423  *
3424  * Typically, a bus driver would store a list of child resources
3425  * somewhere in the child device's ivars (see device_get_ivars()) and
3426  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3427  * then call resource_list_alloc() to perform the allocation.
3428  *
3429  * @param rl		the resource list to allocate from
3430  * @param bus		the parent device of @p child
3431  * @param child		the device which is requesting an allocation
3432  * @param type		the type of resource to allocate
3433  * @param rid		a pointer to the resource identifier
3434  * @param start		hint at the start of the resource range - pass
3435  *			@c 0 for any start address
3436  * @param end		hint at the end of the resource range - pass
3437  *			@c ~0 for any end address
3438  * @param count		hint at the size of range required - pass @c 1
3439  *			for any size
3440  * @param flags		any extra flags to control the resource
3441  *			allocation - see @c RF_XXX flags in
3442  *			<sys/rman.h> for details
3443  *
3444  * @returns		the resource which was allocated or @c NULL if no
3445  *			resource could be allocated
3446  */
3447 struct resource *
3448 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3449     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3450 {
3451 	struct resource_list_entry *rle = NULL;
3452 	int passthrough = (device_get_parent(child) != bus);
3453 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3454 
3455 	if (passthrough) {
3456 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3457 		    type, rid, start, end, count, flags));
3458 	}
3459 
3460 	rle = resource_list_find(rl, type, *rid);
3461 
3462 	if (!rle)
3463 		return (NULL);		/* no resource of that type/rid */
3464 
3465 	if (rle->res) {
3466 		if (rle->flags & RLE_RESERVED) {
3467 			if (rle->flags & RLE_ALLOCATED)
3468 				return (NULL);
3469 			if ((flags & RF_ACTIVE) &&
3470 			    bus_activate_resource(child, type, *rid,
3471 			    rle->res) != 0)
3472 				return (NULL);
3473 			rle->flags |= RLE_ALLOCATED;
3474 			return (rle->res);
3475 		}
3476 		device_printf(bus,
3477 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3478 		    type, device_get_nameunit(child));
3479 		return (NULL);
3480 	}
3481 
3482 	if (isdefault) {
3483 		start = rle->start;
3484 		count = ulmax(count, rle->count);
3485 		end = ulmax(rle->end, start + count - 1);
3486 	}
3487 
3488 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3489 	    type, rid, start, end, count, flags);
3490 
3491 	/*
3492 	 * Record the new range.
3493 	 */
3494 	if (rle->res) {
3495 		rle->start = rman_get_start(rle->res);
3496 		rle->end = rman_get_end(rle->res);
3497 		rle->count = count;
3498 	}
3499 
3500 	return (rle->res);
3501 }
3502 
3503 /**
3504  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3505  *
3506  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3507  * used with resource_list_alloc().
3508  *
3509  * @param rl		the resource list which was allocated from
3510  * @param bus		the parent device of @p child
3511  * @param child		the device which is requesting a release
3512  * @param type		the type of resource to release
3513  * @param rid		the resource identifier
3514  * @param res		the resource to release
3515  *
3516  * @retval 0		success
3517  * @retval non-zero	a standard unix error code indicating what
3518  *			error condition prevented the operation
3519  */
3520 int
3521 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3522     int type, int rid, struct resource *res)
3523 {
3524 	struct resource_list_entry *rle = NULL;
3525 	int passthrough = (device_get_parent(child) != bus);
3526 	int error;
3527 
3528 	if (passthrough) {
3529 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3530 		    type, rid, res));
3531 	}
3532 
3533 	rle = resource_list_find(rl, type, rid);
3534 
3535 	if (!rle)
3536 		panic("resource_list_release: can't find resource");
3537 	if (!rle->res)
3538 		panic("resource_list_release: resource entry is not busy");
3539 	if (rle->flags & RLE_RESERVED) {
3540 		if (rle->flags & RLE_ALLOCATED) {
3541 			if (rman_get_flags(res) & RF_ACTIVE) {
3542 				error = bus_deactivate_resource(child, type,
3543 				    rid, res);
3544 				if (error)
3545 					return (error);
3546 			}
3547 			rle->flags &= ~RLE_ALLOCATED;
3548 			return (0);
3549 		}
3550 		return (EINVAL);
3551 	}
3552 
3553 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3554 	    type, rid, res);
3555 	if (error)
3556 		return (error);
3557 
3558 	rle->res = NULL;
3559 	return (0);
3560 }
3561 
3562 /**
3563  * @brief Release all active resources of a given type
3564  *
3565  * Release all active resources of a specified type.  This is intended
3566  * to be used to cleanup resources leaked by a driver after detach or
3567  * a failed attach.
3568  *
3569  * @param rl		the resource list which was allocated from
3570  * @param bus		the parent device of @p child
3571  * @param child		the device whose active resources are being released
3572  * @param type		the type of resources to release
3573  *
3574  * @retval 0		success
3575  * @retval EBUSY	at least one resource was active
3576  */
3577 int
3578 resource_list_release_active(struct resource_list *rl, device_t bus,
3579     device_t child, int type)
3580 {
3581 	struct resource_list_entry *rle;
3582 	int error, retval;
3583 
3584 	retval = 0;
3585 	STAILQ_FOREACH(rle, rl, link) {
3586 		if (rle->type != type)
3587 			continue;
3588 		if (rle->res == NULL)
3589 			continue;
3590 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3591 		    RLE_RESERVED)
3592 			continue;
3593 		retval = EBUSY;
3594 		error = resource_list_release(rl, bus, child, type,
3595 		    rman_get_rid(rle->res), rle->res);
3596 		if (error != 0)
3597 			device_printf(bus,
3598 			    "Failed to release active resource: %d\n", error);
3599 	}
3600 	return (retval);
3601 }
3602 
3603 /**
3604  * @brief Fully release a reserved resource
3605  *
3606  * Fully releases a resource reserved via resource_list_reserve().
3607  *
3608  * @param rl		the resource list which was allocated from
3609  * @param bus		the parent device of @p child
3610  * @param child		the device whose reserved resource is being released
3611  * @param type		the type of resource to release
3612  * @param rid		the resource identifier
3613  * @param res		the resource to release
3614  *
3615  * @retval 0		success
3616  * @retval non-zero	a standard unix error code indicating what
3617  *			error condition prevented the operation
3618  */
3619 int
3620 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3621     int type, int rid)
3622 {
3623 	struct resource_list_entry *rle = NULL;
3624 	int passthrough = (device_get_parent(child) != bus);
3625 
3626 	if (passthrough)
3627 		panic(
3628     "resource_list_unreserve() should only be called for direct children");
3629 
3630 	rle = resource_list_find(rl, type, rid);
3631 
3632 	if (!rle)
3633 		panic("resource_list_unreserve: can't find resource");
3634 	if (!(rle->flags & RLE_RESERVED))
3635 		return (EINVAL);
3636 	if (rle->flags & RLE_ALLOCATED)
3637 		return (EBUSY);
3638 	rle->flags &= ~RLE_RESERVED;
3639 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3640 }
3641 
3642 /**
3643  * @brief Print a description of resources in a resource list
3644  *
3645  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3646  * The name is printed if at least one resource of the given type is available.
3647  * The format is used to print resource start and end.
3648  *
3649  * @param rl		the resource list to print
3650  * @param name		the name of @p type, e.g. @c "memory"
3651  * @param type		type type of resource entry to print
3652  * @param format	printf(9) format string to print resource
3653  *			start and end values
3654  *
3655  * @returns		the number of characters printed
3656  */
3657 int
3658 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3659     const char *format)
3660 {
3661 	struct resource_list_entry *rle;
3662 	int printed, retval;
3663 
3664 	printed = 0;
3665 	retval = 0;
3666 	/* Yes, this is kinda cheating */
3667 	STAILQ_FOREACH(rle, rl, link) {
3668 		if (rle->type == type) {
3669 			if (printed == 0)
3670 				retval += printf(" %s ", name);
3671 			else
3672 				retval += printf(",");
3673 			printed++;
3674 			retval += printf(format, rle->start);
3675 			if (rle->count > 1) {
3676 				retval += printf("-");
3677 				retval += printf(format, rle->start +
3678 						 rle->count - 1);
3679 			}
3680 		}
3681 	}
3682 	return (retval);
3683 }
3684 
3685 /**
3686  * @brief Releases all the resources in a list.
3687  *
3688  * @param rl		The resource list to purge.
3689  *
3690  * @returns		nothing
3691  */
3692 void
3693 resource_list_purge(struct resource_list *rl)
3694 {
3695 	struct resource_list_entry *rle;
3696 
3697 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3698 		if (rle->res)
3699 			bus_release_resource(rman_get_device(rle->res),
3700 			    rle->type, rle->rid, rle->res);
3701 		STAILQ_REMOVE_HEAD(rl, link);
3702 		free(rle, M_BUS);
3703 	}
3704 }
3705 
3706 device_t
3707 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3708 {
3709 	return (device_add_child_ordered(dev, order, name, unit));
3710 }
3711 
3712 /**
3713  * @brief Helper function for implementing DEVICE_PROBE()
3714  *
3715  * This function can be used to help implement the DEVICE_PROBE() for
3716  * a bus (i.e. a device which has other devices attached to it). It
3717  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3718  * devclass.
3719  */
3720 int
3721 bus_generic_probe(device_t dev)
3722 {
3723 	devclass_t dc = dev->devclass;
3724 	driverlink_t dl;
3725 
3726 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3727 		/*
3728 		 * If this driver's pass is too high, then ignore it.
3729 		 * For most drivers in the default pass, this will
3730 		 * never be true.  For early-pass drivers they will
3731 		 * only call the identify routines of eligible drivers
3732 		 * when this routine is called.  Drivers for later
3733 		 * passes should have their identify routines called
3734 		 * on early-pass buses during BUS_NEW_PASS().
3735 		 */
3736 		if (dl->pass > bus_current_pass)
3737 			continue;
3738 		DEVICE_IDENTIFY(dl->driver, dev);
3739 	}
3740 
3741 	return (0);
3742 }
3743 
3744 /**
3745  * @brief Helper function for implementing DEVICE_ATTACH()
3746  *
3747  * This function can be used to help implement the DEVICE_ATTACH() for
3748  * a bus. It calls device_probe_and_attach() for each of the device's
3749  * children.
3750  */
3751 int
3752 bus_generic_attach(device_t dev)
3753 {
3754 	device_t child;
3755 
3756 	TAILQ_FOREACH(child, &dev->children, link) {
3757 		device_probe_and_attach(child);
3758 	}
3759 
3760 	return (0);
3761 }
3762 
3763 /**
3764  * @brief Helper function for delaying attaching children
3765  *
3766  * Many buses can't run transactions on the bus which children need to probe and
3767  * attach until after interrupts and/or timers are running.  This function
3768  * delays their attach until interrupts and timers are enabled.
3769  */
3770 int
3771 bus_delayed_attach_children(device_t dev)
3772 {
3773 	/* Probe and attach the bus children when interrupts are available */
3774 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3775 
3776 	return (0);
3777 }
3778 
3779 /**
3780  * @brief Helper function for implementing DEVICE_DETACH()
3781  *
3782  * This function can be used to help implement the DEVICE_DETACH() for
3783  * a bus. It calls device_detach() for each of the device's
3784  * children.
3785  */
3786 int
3787 bus_generic_detach(device_t dev)
3788 {
3789 	device_t child;
3790 	int error;
3791 
3792 	if (dev->state != DS_ATTACHED)
3793 		return (EBUSY);
3794 
3795 	/*
3796 	 * Detach children in the reverse order.
3797 	 * See bus_generic_suspend for details.
3798 	 */
3799 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3800 		if ((error = device_detach(child)) != 0)
3801 			return (error);
3802 	}
3803 
3804 	return (0);
3805 }
3806 
3807 /**
3808  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3809  *
3810  * This function can be used to help implement the DEVICE_SHUTDOWN()
3811  * for a bus. It calls device_shutdown() for each of the device's
3812  * children.
3813  */
3814 int
3815 bus_generic_shutdown(device_t dev)
3816 {
3817 	device_t child;
3818 
3819 	/*
3820 	 * Shut down children in the reverse order.
3821 	 * See bus_generic_suspend for details.
3822 	 */
3823 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3824 		device_shutdown(child);
3825 	}
3826 
3827 	return (0);
3828 }
3829 
3830 /**
3831  * @brief Default function for suspending a child device.
3832  *
3833  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3834  */
3835 int
3836 bus_generic_suspend_child(device_t dev, device_t child)
3837 {
3838 	int	error;
3839 
3840 	error = DEVICE_SUSPEND(child);
3841 
3842 	if (error == 0)
3843 		child->flags |= DF_SUSPENDED;
3844 
3845 	return (error);
3846 }
3847 
3848 /**
3849  * @brief Default function for resuming a child device.
3850  *
3851  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3852  */
3853 int
3854 bus_generic_resume_child(device_t dev, device_t child)
3855 {
3856 	DEVICE_RESUME(child);
3857 	child->flags &= ~DF_SUSPENDED;
3858 
3859 	return (0);
3860 }
3861 
3862 /**
3863  * @brief Helper function for implementing DEVICE_SUSPEND()
3864  *
3865  * This function can be used to help implement the DEVICE_SUSPEND()
3866  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3867  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3868  * operation is aborted and any devices which were suspended are
3869  * resumed immediately by calling their DEVICE_RESUME() methods.
3870  */
3871 int
3872 bus_generic_suspend(device_t dev)
3873 {
3874 	int		error;
3875 	device_t	child;
3876 
3877 	/*
3878 	 * Suspend children in the reverse order.
3879 	 * For most buses all children are equal, so the order does not matter.
3880 	 * Other buses, such as acpi, carefully order their child devices to
3881 	 * express implicit dependencies between them.  For such buses it is
3882 	 * safer to bring down devices in the reverse order.
3883 	 */
3884 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3885 		error = BUS_SUSPEND_CHILD(dev, child);
3886 		if (error != 0) {
3887 			child = TAILQ_NEXT(child, link);
3888 			if (child != NULL) {
3889 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3890 					BUS_RESUME_CHILD(dev, child);
3891 			}
3892 			return (error);
3893 		}
3894 	}
3895 	return (0);
3896 }
3897 
3898 /**
3899  * @brief Helper function for implementing DEVICE_RESUME()
3900  *
3901  * This function can be used to help implement the DEVICE_RESUME() for
3902  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3903  */
3904 int
3905 bus_generic_resume(device_t dev)
3906 {
3907 	device_t	child;
3908 
3909 	TAILQ_FOREACH(child, &dev->children, link) {
3910 		BUS_RESUME_CHILD(dev, child);
3911 		/* if resume fails, there's nothing we can usefully do... */
3912 	}
3913 	return (0);
3914 }
3915 
3916 /**
3917  * @brief Helper function for implementing BUS_RESET_POST
3918  *
3919  * Bus can use this function to implement common operations of
3920  * re-attaching or resuming the children after the bus itself was
3921  * reset, and after restoring bus-unique state of children.
3922  *
3923  * @param dev	The bus
3924  * #param flags	DEVF_RESET_*
3925  */
3926 int
3927 bus_helper_reset_post(device_t dev, int flags)
3928 {
3929 	device_t child;
3930 	int error, error1;
3931 
3932 	error = 0;
3933 	TAILQ_FOREACH(child, &dev->children,link) {
3934 		BUS_RESET_POST(dev, child);
3935 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3936 		    device_probe_and_attach(child) :
3937 		    BUS_RESUME_CHILD(dev, child);
3938 		if (error == 0 && error1 != 0)
3939 			error = error1;
3940 	}
3941 	return (error);
3942 }
3943 
3944 static void
3945 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3946 {
3947 	child = TAILQ_NEXT(child, link);
3948 	if (child == NULL)
3949 		return;
3950 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3951 		BUS_RESET_POST(dev, child);
3952 		if ((flags & DEVF_RESET_DETACH) != 0)
3953 			device_probe_and_attach(child);
3954 		else
3955 			BUS_RESUME_CHILD(dev, child);
3956 	}
3957 }
3958 
3959 /**
3960  * @brief Helper function for implementing BUS_RESET_PREPARE
3961  *
3962  * Bus can use this function to implement common operations of
3963  * detaching or suspending the children before the bus itself is
3964  * reset, and then save bus-unique state of children that must
3965  * persists around reset.
3966  *
3967  * @param dev	The bus
3968  * #param flags	DEVF_RESET_*
3969  */
3970 int
3971 bus_helper_reset_prepare(device_t dev, int flags)
3972 {
3973 	device_t child;
3974 	int error;
3975 
3976 	if (dev->state != DS_ATTACHED)
3977 		return (EBUSY);
3978 
3979 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3980 		if ((flags & DEVF_RESET_DETACH) != 0) {
3981 			error = device_get_state(child) == DS_ATTACHED ?
3982 			    device_detach(child) : 0;
3983 		} else {
3984 			error = BUS_SUSPEND_CHILD(dev, child);
3985 		}
3986 		if (error == 0) {
3987 			error = BUS_RESET_PREPARE(dev, child);
3988 			if (error != 0) {
3989 				if ((flags & DEVF_RESET_DETACH) != 0)
3990 					device_probe_and_attach(child);
3991 				else
3992 					BUS_RESUME_CHILD(dev, child);
3993 			}
3994 		}
3995 		if (error != 0) {
3996 			bus_helper_reset_prepare_rollback(dev, child, flags);
3997 			return (error);
3998 		}
3999 	}
4000 	return (0);
4001 }
4002 
4003 /**
4004  * @brief Helper function for implementing BUS_PRINT_CHILD().
4005  *
4006  * This function prints the first part of the ascii representation of
4007  * @p child, including its name, unit and description (if any - see
4008  * device_set_desc()).
4009  *
4010  * @returns the number of characters printed
4011  */
4012 int
4013 bus_print_child_header(device_t dev, device_t child)
4014 {
4015 	int	retval = 0;
4016 
4017 	if (device_get_desc(child)) {
4018 		retval += device_printf(child, "<%s>", device_get_desc(child));
4019 	} else {
4020 		retval += printf("%s", device_get_nameunit(child));
4021 	}
4022 
4023 	return (retval);
4024 }
4025 
4026 /**
4027  * @brief Helper function for implementing BUS_PRINT_CHILD().
4028  *
4029  * This function prints the last part of the ascii representation of
4030  * @p child, which consists of the string @c " on " followed by the
4031  * name and unit of the @p dev.
4032  *
4033  * @returns the number of characters printed
4034  */
4035 int
4036 bus_print_child_footer(device_t dev, device_t child)
4037 {
4038 	return (printf(" on %s\n", device_get_nameunit(dev)));
4039 }
4040 
4041 /**
4042  * @brief Helper function for implementing BUS_PRINT_CHILD().
4043  *
4044  * This function prints out the VM domain for the given device.
4045  *
4046  * @returns the number of characters printed
4047  */
4048 int
4049 bus_print_child_domain(device_t dev, device_t child)
4050 {
4051 	int domain;
4052 
4053 	/* No domain? Don't print anything */
4054 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4055 		return (0);
4056 
4057 	return (printf(" numa-domain %d", domain));
4058 }
4059 
4060 /**
4061  * @brief Helper function for implementing BUS_PRINT_CHILD().
4062  *
4063  * This function simply calls bus_print_child_header() followed by
4064  * bus_print_child_footer().
4065  *
4066  * @returns the number of characters printed
4067  */
4068 int
4069 bus_generic_print_child(device_t dev, device_t child)
4070 {
4071 	int	retval = 0;
4072 
4073 	retval += bus_print_child_header(dev, child);
4074 	retval += bus_print_child_domain(dev, child);
4075 	retval += bus_print_child_footer(dev, child);
4076 
4077 	return (retval);
4078 }
4079 
4080 /**
4081  * @brief Stub function for implementing BUS_READ_IVAR().
4082  *
4083  * @returns ENOENT
4084  */
4085 int
4086 bus_generic_read_ivar(device_t dev, device_t child, int index,
4087     uintptr_t * result)
4088 {
4089 	return (ENOENT);
4090 }
4091 
4092 /**
4093  * @brief Stub function for implementing BUS_WRITE_IVAR().
4094  *
4095  * @returns ENOENT
4096  */
4097 int
4098 bus_generic_write_ivar(device_t dev, device_t child, int index,
4099     uintptr_t value)
4100 {
4101 	return (ENOENT);
4102 }
4103 
4104 /**
4105  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4106  *
4107  * @returns NULL
4108  */
4109 struct resource_list *
4110 bus_generic_get_resource_list(device_t dev, device_t child)
4111 {
4112 	return (NULL);
4113 }
4114 
4115 /**
4116  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4117  *
4118  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4119  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4120  * and then calls device_probe_and_attach() for each unattached child.
4121  */
4122 void
4123 bus_generic_driver_added(device_t dev, driver_t *driver)
4124 {
4125 	device_t child;
4126 
4127 	DEVICE_IDENTIFY(driver, dev);
4128 	TAILQ_FOREACH(child, &dev->children, link) {
4129 		if (child->state == DS_NOTPRESENT)
4130 			device_probe_and_attach(child);
4131 	}
4132 }
4133 
4134 /**
4135  * @brief Helper function for implementing BUS_NEW_PASS().
4136  *
4137  * This implementing of BUS_NEW_PASS() first calls the identify
4138  * routines for any drivers that probe at the current pass.  Then it
4139  * walks the list of devices for this bus.  If a device is already
4140  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4141  * device is not already attached, it attempts to attach a driver to
4142  * it.
4143  */
4144 void
4145 bus_generic_new_pass(device_t dev)
4146 {
4147 	driverlink_t dl;
4148 	devclass_t dc;
4149 	device_t child;
4150 
4151 	dc = dev->devclass;
4152 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4153 		if (dl->pass == bus_current_pass)
4154 			DEVICE_IDENTIFY(dl->driver, dev);
4155 	}
4156 	TAILQ_FOREACH(child, &dev->children, link) {
4157 		if (child->state >= DS_ATTACHED)
4158 			BUS_NEW_PASS(child);
4159 		else if (child->state == DS_NOTPRESENT)
4160 			device_probe_and_attach(child);
4161 	}
4162 }
4163 
4164 /**
4165  * @brief Helper function for implementing BUS_SETUP_INTR().
4166  *
4167  * This simple implementation of BUS_SETUP_INTR() simply calls the
4168  * BUS_SETUP_INTR() method of the parent of @p dev.
4169  */
4170 int
4171 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4172     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4173     void **cookiep)
4174 {
4175 	/* Propagate up the bus hierarchy until someone handles it. */
4176 	if (dev->parent)
4177 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4178 		    filter, intr, arg, cookiep));
4179 	return (EINVAL);
4180 }
4181 
4182 /**
4183  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4184  *
4185  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4186  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4187  */
4188 int
4189 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4190     void *cookie)
4191 {
4192 	/* Propagate up the bus hierarchy until someone handles it. */
4193 	if (dev->parent)
4194 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4195 	return (EINVAL);
4196 }
4197 
4198 /**
4199  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4200  *
4201  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4202  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4203  */
4204 int
4205 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4206 {
4207 	/* Propagate up the bus hierarchy until someone handles it. */
4208 	if (dev->parent)
4209 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4210 	return (EINVAL);
4211 }
4212 
4213 /**
4214  * @brief Helper function for implementing BUS_RESUME_INTR().
4215  *
4216  * This simple implementation of BUS_RESUME_INTR() simply calls the
4217  * BUS_RESUME_INTR() method of the parent of @p dev.
4218  */
4219 int
4220 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4221 {
4222 	/* Propagate up the bus hierarchy until someone handles it. */
4223 	if (dev->parent)
4224 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4225 	return (EINVAL);
4226 }
4227 
4228 /**
4229  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4230  *
4231  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4232  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4233  */
4234 int
4235 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4236     struct resource *r, rman_res_t start, rman_res_t end)
4237 {
4238 	/* Propagate up the bus hierarchy until someone handles it. */
4239 	if (dev->parent)
4240 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4241 		    end));
4242 	return (EINVAL);
4243 }
4244 
4245 /*
4246  * @brief Helper function for implementing BUS_TRANSLATE_RESOURCE().
4247  *
4248  * This simple implementation of BUS_TRANSLATE_RESOURCE() simply calls the
4249  * BUS_TRANSLATE_RESOURCE() method of the parent of @p dev.  If there is no
4250  * parent, no translation happens.
4251  */
4252 int
4253 bus_generic_translate_resource(device_t dev, int type, rman_res_t start,
4254     rman_res_t *newstart)
4255 {
4256 	if (dev->parent)
4257 		return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start,
4258 		    newstart));
4259 	*newstart = start;
4260 	return (0);
4261 }
4262 
4263 /**
4264  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4265  *
4266  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4267  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4268  */
4269 struct resource *
4270 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4271     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4272 {
4273 	/* Propagate up the bus hierarchy until someone handles it. */
4274 	if (dev->parent)
4275 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4276 		    start, end, count, flags));
4277 	return (NULL);
4278 }
4279 
4280 /**
4281  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4282  *
4283  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4284  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4285  */
4286 int
4287 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4288     struct resource *r)
4289 {
4290 	/* Propagate up the bus hierarchy until someone handles it. */
4291 	if (dev->parent)
4292 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4293 		    r));
4294 	return (EINVAL);
4295 }
4296 
4297 /**
4298  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4299  *
4300  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4301  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4302  */
4303 int
4304 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4305     struct resource *r)
4306 {
4307 	/* Propagate up the bus hierarchy until someone handles it. */
4308 	if (dev->parent)
4309 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4310 		    r));
4311 	return (EINVAL);
4312 }
4313 
4314 /**
4315  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4316  *
4317  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4318  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4319  */
4320 int
4321 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4322     int rid, struct resource *r)
4323 {
4324 	/* Propagate up the bus hierarchy until someone handles it. */
4325 	if (dev->parent)
4326 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4327 		    r));
4328 	return (EINVAL);
4329 }
4330 
4331 /**
4332  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4333  *
4334  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4335  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4336  */
4337 int
4338 bus_generic_map_resource(device_t dev, device_t child, int type,
4339     struct resource *r, struct resource_map_request *args,
4340     struct resource_map *map)
4341 {
4342 	/* Propagate up the bus hierarchy until someone handles it. */
4343 	if (dev->parent)
4344 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4345 		    map));
4346 	return (EINVAL);
4347 }
4348 
4349 /**
4350  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4351  *
4352  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4353  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4354  */
4355 int
4356 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4357     struct resource *r, struct resource_map *map)
4358 {
4359 	/* Propagate up the bus hierarchy until someone handles it. */
4360 	if (dev->parent)
4361 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4362 	return (EINVAL);
4363 }
4364 
4365 /**
4366  * @brief Helper function for implementing BUS_BIND_INTR().
4367  *
4368  * This simple implementation of BUS_BIND_INTR() simply calls the
4369  * BUS_BIND_INTR() method of the parent of @p dev.
4370  */
4371 int
4372 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4373     int cpu)
4374 {
4375 	/* Propagate up the bus hierarchy until someone handles it. */
4376 	if (dev->parent)
4377 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4378 	return (EINVAL);
4379 }
4380 
4381 /**
4382  * @brief Helper function for implementing BUS_CONFIG_INTR().
4383  *
4384  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4385  * BUS_CONFIG_INTR() method of the parent of @p dev.
4386  */
4387 int
4388 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4389     enum intr_polarity pol)
4390 {
4391 	/* Propagate up the bus hierarchy until someone handles it. */
4392 	if (dev->parent)
4393 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4394 	return (EINVAL);
4395 }
4396 
4397 /**
4398  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4399  *
4400  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4401  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4402  */
4403 int
4404 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4405     void *cookie, const char *descr)
4406 {
4407 	/* Propagate up the bus hierarchy until someone handles it. */
4408 	if (dev->parent)
4409 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4410 		    descr));
4411 	return (EINVAL);
4412 }
4413 
4414 /**
4415  * @brief Helper function for implementing BUS_GET_CPUS().
4416  *
4417  * This simple implementation of BUS_GET_CPUS() simply calls the
4418  * BUS_GET_CPUS() method of the parent of @p dev.
4419  */
4420 int
4421 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4422     size_t setsize, cpuset_t *cpuset)
4423 {
4424 	/* Propagate up the bus hierarchy until someone handles it. */
4425 	if (dev->parent != NULL)
4426 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4427 	return (EINVAL);
4428 }
4429 
4430 /**
4431  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4432  *
4433  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4434  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4435  */
4436 bus_dma_tag_t
4437 bus_generic_get_dma_tag(device_t dev, device_t child)
4438 {
4439 	/* Propagate up the bus hierarchy until someone handles it. */
4440 	if (dev->parent != NULL)
4441 		return (BUS_GET_DMA_TAG(dev->parent, child));
4442 	return (NULL);
4443 }
4444 
4445 /**
4446  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4447  *
4448  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4449  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4450  */
4451 bus_space_tag_t
4452 bus_generic_get_bus_tag(device_t dev, device_t child)
4453 {
4454 	/* Propagate up the bus hierarchy until someone handles it. */
4455 	if (dev->parent != NULL)
4456 		return (BUS_GET_BUS_TAG(dev->parent, child));
4457 	return ((bus_space_tag_t)0);
4458 }
4459 
4460 /**
4461  * @brief Helper function for implementing BUS_GET_RESOURCE().
4462  *
4463  * This implementation of BUS_GET_RESOURCE() uses the
4464  * resource_list_find() function to do most of the work. It calls
4465  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4466  * search.
4467  */
4468 int
4469 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4470     rman_res_t *startp, rman_res_t *countp)
4471 {
4472 	struct resource_list *		rl = NULL;
4473 	struct resource_list_entry *	rle = NULL;
4474 
4475 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4476 	if (!rl)
4477 		return (EINVAL);
4478 
4479 	rle = resource_list_find(rl, type, rid);
4480 	if (!rle)
4481 		return (ENOENT);
4482 
4483 	if (startp)
4484 		*startp = rle->start;
4485 	if (countp)
4486 		*countp = rle->count;
4487 
4488 	return (0);
4489 }
4490 
4491 /**
4492  * @brief Helper function for implementing BUS_SET_RESOURCE().
4493  *
4494  * This implementation of BUS_SET_RESOURCE() uses the
4495  * resource_list_add() function to do most of the work. It calls
4496  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4497  * edit.
4498  */
4499 int
4500 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4501     rman_res_t start, rman_res_t count)
4502 {
4503 	struct resource_list *		rl = NULL;
4504 
4505 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4506 	if (!rl)
4507 		return (EINVAL);
4508 
4509 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4510 
4511 	return (0);
4512 }
4513 
4514 /**
4515  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4516  *
4517  * This implementation of BUS_DELETE_RESOURCE() uses the
4518  * resource_list_delete() function to do most of the work. It calls
4519  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4520  * edit.
4521  */
4522 void
4523 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4524 {
4525 	struct resource_list *		rl = NULL;
4526 
4527 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4528 	if (!rl)
4529 		return;
4530 
4531 	resource_list_delete(rl, type, rid);
4532 
4533 	return;
4534 }
4535 
4536 /**
4537  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4538  *
4539  * This implementation of BUS_RELEASE_RESOURCE() uses the
4540  * resource_list_release() function to do most of the work. It calls
4541  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4542  */
4543 int
4544 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4545     int rid, struct resource *r)
4546 {
4547 	struct resource_list *		rl = NULL;
4548 
4549 	if (device_get_parent(child) != dev)
4550 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4551 		    type, rid, r));
4552 
4553 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4554 	if (!rl)
4555 		return (EINVAL);
4556 
4557 	return (resource_list_release(rl, dev, child, type, rid, r));
4558 }
4559 
4560 /**
4561  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4562  *
4563  * This implementation of BUS_ALLOC_RESOURCE() uses the
4564  * resource_list_alloc() function to do most of the work. It calls
4565  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4566  */
4567 struct resource *
4568 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4569     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4570 {
4571 	struct resource_list *		rl = NULL;
4572 
4573 	if (device_get_parent(child) != dev)
4574 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4575 		    type, rid, start, end, count, flags));
4576 
4577 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4578 	if (!rl)
4579 		return (NULL);
4580 
4581 	return (resource_list_alloc(rl, dev, child, type, rid,
4582 	    start, end, count, flags));
4583 }
4584 
4585 /**
4586  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4587  *
4588  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4589  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4590  */
4591 int
4592 bus_generic_child_present(device_t dev, device_t child)
4593 {
4594 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4595 }
4596 
4597 int
4598 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4599 {
4600 	if (dev->parent)
4601 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4602 
4603 	return (ENOENT);
4604 }
4605 
4606 /**
4607  * @brief Helper function for implementing BUS_RESCAN().
4608  *
4609  * This null implementation of BUS_RESCAN() always fails to indicate
4610  * the bus does not support rescanning.
4611  */
4612 int
4613 bus_null_rescan(device_t dev)
4614 {
4615 	return (ENXIO);
4616 }
4617 
4618 /*
4619  * Some convenience functions to make it easier for drivers to use the
4620  * resource-management functions.  All these really do is hide the
4621  * indirection through the parent's method table, making for slightly
4622  * less-wordy code.  In the future, it might make sense for this code
4623  * to maintain some sort of a list of resources allocated by each device.
4624  */
4625 
4626 int
4627 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4628     struct resource **res)
4629 {
4630 	int i;
4631 
4632 	for (i = 0; rs[i].type != -1; i++)
4633 		res[i] = NULL;
4634 	for (i = 0; rs[i].type != -1; i++) {
4635 		res[i] = bus_alloc_resource_any(dev,
4636 		    rs[i].type, &rs[i].rid, rs[i].flags);
4637 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4638 			bus_release_resources(dev, rs, res);
4639 			return (ENXIO);
4640 		}
4641 	}
4642 	return (0);
4643 }
4644 
4645 void
4646 bus_release_resources(device_t dev, const struct resource_spec *rs,
4647     struct resource **res)
4648 {
4649 	int i;
4650 
4651 	for (i = 0; rs[i].type != -1; i++)
4652 		if (res[i] != NULL) {
4653 			bus_release_resource(
4654 			    dev, rs[i].type, rs[i].rid, res[i]);
4655 			res[i] = NULL;
4656 		}
4657 }
4658 
4659 /**
4660  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4661  *
4662  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4663  * parent of @p dev.
4664  */
4665 struct resource *
4666 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4667     rman_res_t end, rman_res_t count, u_int flags)
4668 {
4669 	struct resource *res;
4670 
4671 	if (dev->parent == NULL)
4672 		return (NULL);
4673 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4674 	    count, flags);
4675 	return (res);
4676 }
4677 
4678 /**
4679  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4680  *
4681  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4682  * parent of @p dev.
4683  */
4684 int
4685 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4686     rman_res_t end)
4687 {
4688 	if (dev->parent == NULL)
4689 		return (EINVAL);
4690 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4691 }
4692 
4693 /**
4694  * @brief Wrapper function for BUS_TRANSLATE_RESOURCE().
4695  *
4696  * This function simply calls the BUS_TRANSLATE_RESOURCE() method of the
4697  * parent of @p dev.
4698  */
4699 int
4700 bus_translate_resource(device_t dev, int type, rman_res_t start,
4701     rman_res_t *newstart)
4702 {
4703 	if (dev->parent == NULL)
4704 		return (EINVAL);
4705 	return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start, newstart));
4706 }
4707 
4708 /**
4709  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4710  *
4711  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4712  * parent of @p dev.
4713  */
4714 int
4715 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4716 {
4717 	if (dev->parent == NULL)
4718 		return (EINVAL);
4719 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4720 }
4721 
4722 /**
4723  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4724  *
4725  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4726  * parent of @p dev.
4727  */
4728 int
4729 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4730 {
4731 	if (dev->parent == NULL)
4732 		return (EINVAL);
4733 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4734 }
4735 
4736 /**
4737  * @brief Wrapper function for BUS_MAP_RESOURCE().
4738  *
4739  * This function simply calls the BUS_MAP_RESOURCE() method of the
4740  * parent of @p dev.
4741  */
4742 int
4743 bus_map_resource(device_t dev, int type, struct resource *r,
4744     struct resource_map_request *args, struct resource_map *map)
4745 {
4746 	if (dev->parent == NULL)
4747 		return (EINVAL);
4748 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4749 }
4750 
4751 /**
4752  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4753  *
4754  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4755  * parent of @p dev.
4756  */
4757 int
4758 bus_unmap_resource(device_t dev, int type, struct resource *r,
4759     struct resource_map *map)
4760 {
4761 	if (dev->parent == NULL)
4762 		return (EINVAL);
4763 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4764 }
4765 
4766 /**
4767  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4768  *
4769  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4770  * parent of @p dev.
4771  */
4772 int
4773 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4774 {
4775 	int rv;
4776 
4777 	if (dev->parent == NULL)
4778 		return (EINVAL);
4779 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4780 	return (rv);
4781 }
4782 
4783 /**
4784  * @brief Wrapper function for BUS_SETUP_INTR().
4785  *
4786  * This function simply calls the BUS_SETUP_INTR() method of the
4787  * parent of @p dev.
4788  */
4789 int
4790 bus_setup_intr(device_t dev, struct resource *r, int flags,
4791     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4792 {
4793 	int error;
4794 
4795 	if (dev->parent == NULL)
4796 		return (EINVAL);
4797 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4798 	    arg, cookiep);
4799 	if (error != 0)
4800 		return (error);
4801 	if (handler != NULL && !(flags & INTR_MPSAFE))
4802 		device_printf(dev, "[GIANT-LOCKED]\n");
4803 	return (0);
4804 }
4805 
4806 /**
4807  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4808  *
4809  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4810  * parent of @p dev.
4811  */
4812 int
4813 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4814 {
4815 	if (dev->parent == NULL)
4816 		return (EINVAL);
4817 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4818 }
4819 
4820 /**
4821  * @brief Wrapper function for BUS_SUSPEND_INTR().
4822  *
4823  * This function simply calls the BUS_SUSPEND_INTR() method of the
4824  * parent of @p dev.
4825  */
4826 int
4827 bus_suspend_intr(device_t dev, struct resource *r)
4828 {
4829 	if (dev->parent == NULL)
4830 		return (EINVAL);
4831 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4832 }
4833 
4834 /**
4835  * @brief Wrapper function for BUS_RESUME_INTR().
4836  *
4837  * This function simply calls the BUS_RESUME_INTR() method of the
4838  * parent of @p dev.
4839  */
4840 int
4841 bus_resume_intr(device_t dev, struct resource *r)
4842 {
4843 	if (dev->parent == NULL)
4844 		return (EINVAL);
4845 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4846 }
4847 
4848 /**
4849  * @brief Wrapper function for BUS_BIND_INTR().
4850  *
4851  * This function simply calls the BUS_BIND_INTR() method of the
4852  * parent of @p dev.
4853  */
4854 int
4855 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4856 {
4857 	if (dev->parent == NULL)
4858 		return (EINVAL);
4859 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4860 }
4861 
4862 /**
4863  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4864  *
4865  * This function first formats the requested description into a
4866  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4867  * the parent of @p dev.
4868  */
4869 int
4870 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4871     const char *fmt, ...)
4872 {
4873 	va_list ap;
4874 	char descr[MAXCOMLEN + 1];
4875 
4876 	if (dev->parent == NULL)
4877 		return (EINVAL);
4878 	va_start(ap, fmt);
4879 	vsnprintf(descr, sizeof(descr), fmt, ap);
4880 	va_end(ap);
4881 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4882 }
4883 
4884 /**
4885  * @brief Wrapper function for BUS_SET_RESOURCE().
4886  *
4887  * This function simply calls the BUS_SET_RESOURCE() method of the
4888  * parent of @p dev.
4889  */
4890 int
4891 bus_set_resource(device_t dev, int type, int rid,
4892     rman_res_t start, rman_res_t count)
4893 {
4894 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4895 	    start, count));
4896 }
4897 
4898 /**
4899  * @brief Wrapper function for BUS_GET_RESOURCE().
4900  *
4901  * This function simply calls the BUS_GET_RESOURCE() method of the
4902  * parent of @p dev.
4903  */
4904 int
4905 bus_get_resource(device_t dev, int type, int rid,
4906     rman_res_t *startp, rman_res_t *countp)
4907 {
4908 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4909 	    startp, countp));
4910 }
4911 
4912 /**
4913  * @brief Wrapper function for BUS_GET_RESOURCE().
4914  *
4915  * This function simply calls the BUS_GET_RESOURCE() method of the
4916  * parent of @p dev and returns the start value.
4917  */
4918 rman_res_t
4919 bus_get_resource_start(device_t dev, int type, int rid)
4920 {
4921 	rman_res_t start;
4922 	rman_res_t count;
4923 	int error;
4924 
4925 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4926 	    &start, &count);
4927 	if (error)
4928 		return (0);
4929 	return (start);
4930 }
4931 
4932 /**
4933  * @brief Wrapper function for BUS_GET_RESOURCE().
4934  *
4935  * This function simply calls the BUS_GET_RESOURCE() method of the
4936  * parent of @p dev and returns the count value.
4937  */
4938 rman_res_t
4939 bus_get_resource_count(device_t dev, int type, int rid)
4940 {
4941 	rman_res_t start;
4942 	rman_res_t count;
4943 	int error;
4944 
4945 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4946 	    &start, &count);
4947 	if (error)
4948 		return (0);
4949 	return (count);
4950 }
4951 
4952 /**
4953  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4954  *
4955  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4956  * parent of @p dev.
4957  */
4958 void
4959 bus_delete_resource(device_t dev, int type, int rid)
4960 {
4961 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4962 }
4963 
4964 /**
4965  * @brief Wrapper function for BUS_CHILD_PRESENT().
4966  *
4967  * This function simply calls the BUS_CHILD_PRESENT() method of the
4968  * parent of @p dev.
4969  */
4970 int
4971 bus_child_present(device_t child)
4972 {
4973 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4974 }
4975 
4976 /**
4977  * @brief Wrapper function for BUS_CHILD_PNPINFO().
4978  *
4979  * This function simply calls the BUS_CHILD_PNPINFO() method of the parent of @p
4980  * dev.
4981  */
4982 int
4983 bus_child_pnpinfo(device_t child, struct sbuf *sb)
4984 {
4985 	device_t parent;
4986 
4987 	parent = device_get_parent(child);
4988 	if (parent == NULL)
4989 		return (0);
4990 	return (BUS_CHILD_PNPINFO(parent, child, sb));
4991 }
4992 
4993 /**
4994  * @brief Generic implementation that does nothing for bus_child_pnpinfo
4995  *
4996  * This function has the right signature and returns 0 since the sbuf is passed
4997  * to us to append to.
4998  */
4999 int
5000 bus_generic_child_pnpinfo(device_t dev, device_t child, struct sbuf *sb)
5001 {
5002 	return (0);
5003 }
5004 
5005 /**
5006  * @brief Wrapper function for BUS_CHILD_LOCATION().
5007  *
5008  * This function simply calls the BUS_CHILD_LOCATION() method of the parent of
5009  * @p dev.
5010  */
5011 int
5012 bus_child_location(device_t child, struct sbuf *sb)
5013 {
5014 	device_t parent;
5015 
5016 	parent = device_get_parent(child);
5017 	if (parent == NULL)
5018 		return (0);
5019 	return (BUS_CHILD_LOCATION(parent, child, sb));
5020 }
5021 
5022 /**
5023  * @brief Generic implementation that does nothing for bus_child_location
5024  *
5025  * This function has the right signature and returns 0 since the sbuf is passed
5026  * to us to append to.
5027  */
5028 int
5029 bus_generic_child_location(device_t dev, device_t child, struct sbuf *sb)
5030 {
5031 	return (0);
5032 }
5033 
5034 /**
5035  * @brief Wrapper function for BUS_GET_CPUS().
5036  *
5037  * This function simply calls the BUS_GET_CPUS() method of the
5038  * parent of @p dev.
5039  */
5040 int
5041 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5042 {
5043 	device_t parent;
5044 
5045 	parent = device_get_parent(dev);
5046 	if (parent == NULL)
5047 		return (EINVAL);
5048 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5049 }
5050 
5051 /**
5052  * @brief Wrapper function for BUS_GET_DMA_TAG().
5053  *
5054  * This function simply calls the BUS_GET_DMA_TAG() method of the
5055  * parent of @p dev.
5056  */
5057 bus_dma_tag_t
5058 bus_get_dma_tag(device_t dev)
5059 {
5060 	device_t parent;
5061 
5062 	parent = device_get_parent(dev);
5063 	if (parent == NULL)
5064 		return (NULL);
5065 	return (BUS_GET_DMA_TAG(parent, dev));
5066 }
5067 
5068 /**
5069  * @brief Wrapper function for BUS_GET_BUS_TAG().
5070  *
5071  * This function simply calls the BUS_GET_BUS_TAG() method of the
5072  * parent of @p dev.
5073  */
5074 bus_space_tag_t
5075 bus_get_bus_tag(device_t dev)
5076 {
5077 	device_t parent;
5078 
5079 	parent = device_get_parent(dev);
5080 	if (parent == NULL)
5081 		return ((bus_space_tag_t)0);
5082 	return (BUS_GET_BUS_TAG(parent, dev));
5083 }
5084 
5085 /**
5086  * @brief Wrapper function for BUS_GET_DOMAIN().
5087  *
5088  * This function simply calls the BUS_GET_DOMAIN() method of the
5089  * parent of @p dev.
5090  */
5091 int
5092 bus_get_domain(device_t dev, int *domain)
5093 {
5094 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5095 }
5096 
5097 /* Resume all devices and then notify userland that we're up again. */
5098 static int
5099 root_resume(device_t dev)
5100 {
5101 	int error;
5102 
5103 	error = bus_generic_resume(dev);
5104 	if (error == 0) {
5105 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5106 		devctl_notify("kernel", "power", "resume", NULL);
5107 	}
5108 	return (error);
5109 }
5110 
5111 static int
5112 root_print_child(device_t dev, device_t child)
5113 {
5114 	int	retval = 0;
5115 
5116 	retval += bus_print_child_header(dev, child);
5117 	retval += printf("\n");
5118 
5119 	return (retval);
5120 }
5121 
5122 static int
5123 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5124     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5125 {
5126 	/*
5127 	 * If an interrupt mapping gets to here something bad has happened.
5128 	 */
5129 	panic("root_setup_intr");
5130 }
5131 
5132 /*
5133  * If we get here, assume that the device is permanent and really is
5134  * present in the system.  Removable bus drivers are expected to intercept
5135  * this call long before it gets here.  We return -1 so that drivers that
5136  * really care can check vs -1 or some ERRNO returned higher in the food
5137  * chain.
5138  */
5139 static int
5140 root_child_present(device_t dev, device_t child)
5141 {
5142 	return (-1);
5143 }
5144 
5145 static int
5146 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5147     cpuset_t *cpuset)
5148 {
5149 	switch (op) {
5150 	case INTR_CPUS:
5151 		/* Default to returning the set of all CPUs. */
5152 		if (setsize != sizeof(cpuset_t))
5153 			return (EINVAL);
5154 		*cpuset = all_cpus;
5155 		return (0);
5156 	default:
5157 		return (EINVAL);
5158 	}
5159 }
5160 
5161 static kobj_method_t root_methods[] = {
5162 	/* Device interface */
5163 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5164 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5165 	KOBJMETHOD(device_resume,	root_resume),
5166 
5167 	/* Bus interface */
5168 	KOBJMETHOD(bus_print_child,	root_print_child),
5169 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5170 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5171 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5172 	KOBJMETHOD(bus_child_present,	root_child_present),
5173 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5174 
5175 	KOBJMETHOD_END
5176 };
5177 
5178 static driver_t root_driver = {
5179 	"root",
5180 	root_methods,
5181 	1,			/* no softc */
5182 };
5183 
5184 device_t	root_bus;
5185 devclass_t	root_devclass;
5186 
5187 static int
5188 root_bus_module_handler(module_t mod, int what, void* arg)
5189 {
5190 	switch (what) {
5191 	case MOD_LOAD:
5192 		TAILQ_INIT(&bus_data_devices);
5193 		kobj_class_compile((kobj_class_t) &root_driver);
5194 		root_bus = make_device(NULL, "root", 0);
5195 		root_bus->desc = "System root bus";
5196 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5197 		root_bus->driver = &root_driver;
5198 		root_bus->state = DS_ATTACHED;
5199 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5200 		devinit();
5201 		return (0);
5202 
5203 	case MOD_SHUTDOWN:
5204 		device_shutdown(root_bus);
5205 		return (0);
5206 	default:
5207 		return (EOPNOTSUPP);
5208 	}
5209 
5210 	return (0);
5211 }
5212 
5213 static moduledata_t root_bus_mod = {
5214 	"rootbus",
5215 	root_bus_module_handler,
5216 	NULL
5217 };
5218 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5219 
5220 /**
5221  * @brief Automatically configure devices
5222  *
5223  * This function begins the autoconfiguration process by calling
5224  * device_probe_and_attach() for each child of the @c root0 device.
5225  */
5226 void
5227 root_bus_configure(void)
5228 {
5229 	PDEBUG(("."));
5230 
5231 	/* Eventually this will be split up, but this is sufficient for now. */
5232 	bus_set_pass(BUS_PASS_DEFAULT);
5233 }
5234 
5235 /**
5236  * @brief Module handler for registering device drivers
5237  *
5238  * This module handler is used to automatically register device
5239  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5240  * devclass_add_driver() for the driver described by the
5241  * driver_module_data structure pointed to by @p arg
5242  */
5243 int
5244 driver_module_handler(module_t mod, int what, void *arg)
5245 {
5246 	struct driver_module_data *dmd;
5247 	devclass_t bus_devclass;
5248 	kobj_class_t driver;
5249 	int error, pass;
5250 
5251 	dmd = (struct driver_module_data *)arg;
5252 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5253 	error = 0;
5254 
5255 	switch (what) {
5256 	case MOD_LOAD:
5257 		if (dmd->dmd_chainevh)
5258 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5259 
5260 		pass = dmd->dmd_pass;
5261 		driver = dmd->dmd_driver;
5262 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5263 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5264 		error = devclass_add_driver(bus_devclass, driver, pass,
5265 		    dmd->dmd_devclass);
5266 		break;
5267 
5268 	case MOD_UNLOAD:
5269 		PDEBUG(("Unloading module: driver %s from bus %s",
5270 		    DRIVERNAME(dmd->dmd_driver),
5271 		    dmd->dmd_busname));
5272 		error = devclass_delete_driver(bus_devclass,
5273 		    dmd->dmd_driver);
5274 
5275 		if (!error && dmd->dmd_chainevh)
5276 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5277 		break;
5278 	case MOD_QUIESCE:
5279 		PDEBUG(("Quiesce module: driver %s from bus %s",
5280 		    DRIVERNAME(dmd->dmd_driver),
5281 		    dmd->dmd_busname));
5282 		error = devclass_quiesce_driver(bus_devclass,
5283 		    dmd->dmd_driver);
5284 
5285 		if (!error && dmd->dmd_chainevh)
5286 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5287 		break;
5288 	default:
5289 		error = EOPNOTSUPP;
5290 		break;
5291 	}
5292 
5293 	return (error);
5294 }
5295 
5296 /**
5297  * @brief Enumerate all hinted devices for this bus.
5298  *
5299  * Walks through the hints for this bus and calls the bus_hinted_child
5300  * routine for each one it fines.  It searches first for the specific
5301  * bus that's being probed for hinted children (eg isa0), and then for
5302  * generic children (eg isa).
5303  *
5304  * @param	dev	bus device to enumerate
5305  */
5306 void
5307 bus_enumerate_hinted_children(device_t bus)
5308 {
5309 	int i;
5310 	const char *dname, *busname;
5311 	int dunit;
5312 
5313 	/*
5314 	 * enumerate all devices on the specific bus
5315 	 */
5316 	busname = device_get_nameunit(bus);
5317 	i = 0;
5318 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5319 		BUS_HINTED_CHILD(bus, dname, dunit);
5320 
5321 	/*
5322 	 * and all the generic ones.
5323 	 */
5324 	busname = device_get_name(bus);
5325 	i = 0;
5326 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5327 		BUS_HINTED_CHILD(bus, dname, dunit);
5328 }
5329 
5330 #ifdef BUS_DEBUG
5331 
5332 /* the _short versions avoid iteration by not calling anything that prints
5333  * more than oneliners. I love oneliners.
5334  */
5335 
5336 static void
5337 print_device_short(device_t dev, int indent)
5338 {
5339 	if (!dev)
5340 		return;
5341 
5342 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5343 	    dev->unit, dev->desc,
5344 	    (dev->parent? "":"no "),
5345 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5346 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5347 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5348 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5349 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5350 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5351 	    (dev->ivars? "":"no "),
5352 	    (dev->softc? "":"no "),
5353 	    dev->busy));
5354 }
5355 
5356 static void
5357 print_device(device_t dev, int indent)
5358 {
5359 	if (!dev)
5360 		return;
5361 
5362 	print_device_short(dev, indent);
5363 
5364 	indentprintf(("Parent:\n"));
5365 	print_device_short(dev->parent, indent+1);
5366 	indentprintf(("Driver:\n"));
5367 	print_driver_short(dev->driver, indent+1);
5368 	indentprintf(("Devclass:\n"));
5369 	print_devclass_short(dev->devclass, indent+1);
5370 }
5371 
5372 void
5373 print_device_tree_short(device_t dev, int indent)
5374 /* print the device and all its children (indented) */
5375 {
5376 	device_t child;
5377 
5378 	if (!dev)
5379 		return;
5380 
5381 	print_device_short(dev, indent);
5382 
5383 	TAILQ_FOREACH(child, &dev->children, link) {
5384 		print_device_tree_short(child, indent+1);
5385 	}
5386 }
5387 
5388 void
5389 print_device_tree(device_t dev, int indent)
5390 /* print the device and all its children (indented) */
5391 {
5392 	device_t child;
5393 
5394 	if (!dev)
5395 		return;
5396 
5397 	print_device(dev, indent);
5398 
5399 	TAILQ_FOREACH(child, &dev->children, link) {
5400 		print_device_tree(child, indent+1);
5401 	}
5402 }
5403 
5404 static void
5405 print_driver_short(driver_t *driver, int indent)
5406 {
5407 	if (!driver)
5408 		return;
5409 
5410 	indentprintf(("driver %s: softc size = %zd\n",
5411 	    driver->name, driver->size));
5412 }
5413 
5414 static void
5415 print_driver(driver_t *driver, int indent)
5416 {
5417 	if (!driver)
5418 		return;
5419 
5420 	print_driver_short(driver, indent);
5421 }
5422 
5423 static void
5424 print_driver_list(driver_list_t drivers, int indent)
5425 {
5426 	driverlink_t driver;
5427 
5428 	TAILQ_FOREACH(driver, &drivers, link) {
5429 		print_driver(driver->driver, indent);
5430 	}
5431 }
5432 
5433 static void
5434 print_devclass_short(devclass_t dc, int indent)
5435 {
5436 	if ( !dc )
5437 		return;
5438 
5439 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5440 }
5441 
5442 static void
5443 print_devclass(devclass_t dc, int indent)
5444 {
5445 	int i;
5446 
5447 	if ( !dc )
5448 		return;
5449 
5450 	print_devclass_short(dc, indent);
5451 	indentprintf(("Drivers:\n"));
5452 	print_driver_list(dc->drivers, indent+1);
5453 
5454 	indentprintf(("Devices:\n"));
5455 	for (i = 0; i < dc->maxunit; i++)
5456 		if (dc->devices[i])
5457 			print_device(dc->devices[i], indent+1);
5458 }
5459 
5460 void
5461 print_devclass_list_short(void)
5462 {
5463 	devclass_t dc;
5464 
5465 	printf("Short listing of devclasses, drivers & devices:\n");
5466 	TAILQ_FOREACH(dc, &devclasses, link) {
5467 		print_devclass_short(dc, 0);
5468 	}
5469 }
5470 
5471 void
5472 print_devclass_list(void)
5473 {
5474 	devclass_t dc;
5475 
5476 	printf("Full listing of devclasses, drivers & devices:\n");
5477 	TAILQ_FOREACH(dc, &devclasses, link) {
5478 		print_devclass(dc, 0);
5479 	}
5480 }
5481 
5482 #endif
5483 
5484 /*
5485  * User-space access to the device tree.
5486  *
5487  * We implement a small set of nodes:
5488  *
5489  * hw.bus			Single integer read method to obtain the
5490  *				current generation count.
5491  * hw.bus.devices		Reads the entire device tree in flat space.
5492  * hw.bus.rman			Resource manager interface
5493  *
5494  * We might like to add the ability to scan devclasses and/or drivers to
5495  * determine what else is currently loaded/available.
5496  */
5497 
5498 static int
5499 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5500 {
5501 	struct u_businfo	ubus;
5502 
5503 	ubus.ub_version = BUS_USER_VERSION;
5504 	ubus.ub_generation = bus_data_generation;
5505 
5506 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5507 }
5508 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5509     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5510     "bus-related data");
5511 
5512 static int
5513 sysctl_devices(SYSCTL_HANDLER_ARGS)
5514 {
5515 	struct sbuf		sb;
5516 	int			*name = (int *)arg1;
5517 	u_int			namelen = arg2;
5518 	int			index;
5519 	device_t		dev;
5520 	struct u_device		*udev;
5521 	int			error;
5522 
5523 	if (namelen != 2)
5524 		return (EINVAL);
5525 
5526 	if (bus_data_generation_check(name[0]))
5527 		return (EINVAL);
5528 
5529 	index = name[1];
5530 
5531 	/*
5532 	 * Scan the list of devices, looking for the requested index.
5533 	 */
5534 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5535 		if (index-- == 0)
5536 			break;
5537 	}
5538 	if (dev == NULL)
5539 		return (ENOENT);
5540 
5541 	/*
5542 	 * Populate the return item, careful not to overflow the buffer.
5543 	 */
5544 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5545 	if (udev == NULL)
5546 		return (ENOMEM);
5547 	udev->dv_handle = (uintptr_t)dev;
5548 	udev->dv_parent = (uintptr_t)dev->parent;
5549 	udev->dv_devflags = dev->devflags;
5550 	udev->dv_flags = dev->flags;
5551 	udev->dv_state = dev->state;
5552 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5553 	if (dev->nameunit != NULL)
5554 		sbuf_cat(&sb, dev->nameunit);
5555 	sbuf_putc(&sb, '\0');
5556 	if (dev->desc != NULL)
5557 		sbuf_cat(&sb, dev->desc);
5558 	sbuf_putc(&sb, '\0');
5559 	if (dev->driver != NULL)
5560 		sbuf_cat(&sb, dev->driver->name);
5561 	sbuf_putc(&sb, '\0');
5562 	bus_child_pnpinfo(dev, &sb);
5563 	sbuf_putc(&sb, '\0');
5564 	bus_child_location(dev, &sb);
5565 	sbuf_putc(&sb, '\0');
5566 	error = sbuf_finish(&sb);
5567 	if (error == 0)
5568 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5569 	sbuf_delete(&sb);
5570 	free(udev, M_BUS);
5571 	return (error);
5572 }
5573 
5574 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5575     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5576     "system device tree");
5577 
5578 int
5579 bus_data_generation_check(int generation)
5580 {
5581 	if (generation != bus_data_generation)
5582 		return (1);
5583 
5584 	/* XXX generate optimised lists here? */
5585 	return (0);
5586 }
5587 
5588 void
5589 bus_data_generation_update(void)
5590 {
5591 	atomic_add_int(&bus_data_generation, 1);
5592 }
5593 
5594 int
5595 bus_free_resource(device_t dev, int type, struct resource *r)
5596 {
5597 	if (r == NULL)
5598 		return (0);
5599 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5600 }
5601 
5602 device_t
5603 device_lookup_by_name(const char *name)
5604 {
5605 	device_t dev;
5606 
5607 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5608 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5609 			return (dev);
5610 	}
5611 	return (NULL);
5612 }
5613 
5614 /*
5615  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5616  * implicit semantics on open, so it could not be reused for this.
5617  * Another option would be to call this /dev/bus?
5618  */
5619 static int
5620 find_device(struct devreq *req, device_t *devp)
5621 {
5622 	device_t dev;
5623 
5624 	/*
5625 	 * First, ensure that the name is nul terminated.
5626 	 */
5627 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5628 		return (EINVAL);
5629 
5630 	/*
5631 	 * Second, try to find an attached device whose name matches
5632 	 * 'name'.
5633 	 */
5634 	dev = device_lookup_by_name(req->dr_name);
5635 	if (dev != NULL) {
5636 		*devp = dev;
5637 		return (0);
5638 	}
5639 
5640 	/* Finally, give device enumerators a chance. */
5641 	dev = NULL;
5642 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5643 	if (dev == NULL)
5644 		return (ENOENT);
5645 	*devp = dev;
5646 	return (0);
5647 }
5648 
5649 static bool
5650 driver_exists(device_t bus, const char *driver)
5651 {
5652 	devclass_t dc;
5653 
5654 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5655 		if (devclass_find_driver_internal(dc, driver) != NULL)
5656 			return (true);
5657 	}
5658 	return (false);
5659 }
5660 
5661 static void
5662 device_gen_nomatch(device_t dev)
5663 {
5664 	device_t child;
5665 
5666 	if (dev->flags & DF_NEEDNOMATCH &&
5667 	    dev->state == DS_NOTPRESENT) {
5668 		BUS_PROBE_NOMATCH(dev->parent, dev);
5669 		devnomatch(dev);
5670 		dev->flags |= DF_DONENOMATCH;
5671 	}
5672 	dev->flags &= ~DF_NEEDNOMATCH;
5673 	TAILQ_FOREACH(child, &dev->children, link) {
5674 		device_gen_nomatch(child);
5675 	}
5676 }
5677 
5678 static void
5679 device_do_deferred_actions(void)
5680 {
5681 	devclass_t dc;
5682 	driverlink_t dl;
5683 
5684 	/*
5685 	 * Walk through the devclasses to find all the drivers we've tagged as
5686 	 * deferred during the freeze and call the driver added routines. They
5687 	 * have already been added to the lists in the background, so the driver
5688 	 * added routines that trigger a probe will have all the right bidders
5689 	 * for the probe auction.
5690 	 */
5691 	TAILQ_FOREACH(dc, &devclasses, link) {
5692 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5693 			if (dl->flags & DL_DEFERRED_PROBE) {
5694 				devclass_driver_added(dc, dl->driver);
5695 				dl->flags &= ~DL_DEFERRED_PROBE;
5696 			}
5697 		}
5698 	}
5699 
5700 	/*
5701 	 * We also defer no-match events during a freeze. Walk the tree and
5702 	 * generate all the pent-up events that are still relevant.
5703 	 */
5704 	device_gen_nomatch(root_bus);
5705 	bus_data_generation_update();
5706 }
5707 
5708 static int
5709 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5710     struct thread *td)
5711 {
5712 	struct devreq *req;
5713 	device_t dev;
5714 	int error, old;
5715 
5716 	/* Locate the device to control. */
5717 	mtx_lock(&Giant);
5718 	req = (struct devreq *)data;
5719 	switch (cmd) {
5720 	case DEV_ATTACH:
5721 	case DEV_DETACH:
5722 	case DEV_ENABLE:
5723 	case DEV_DISABLE:
5724 	case DEV_SUSPEND:
5725 	case DEV_RESUME:
5726 	case DEV_SET_DRIVER:
5727 	case DEV_CLEAR_DRIVER:
5728 	case DEV_RESCAN:
5729 	case DEV_DELETE:
5730 	case DEV_RESET:
5731 		error = priv_check(td, PRIV_DRIVER);
5732 		if (error == 0)
5733 			error = find_device(req, &dev);
5734 		break;
5735 	case DEV_FREEZE:
5736 	case DEV_THAW:
5737 		error = priv_check(td, PRIV_DRIVER);
5738 		break;
5739 	default:
5740 		error = ENOTTY;
5741 		break;
5742 	}
5743 	if (error) {
5744 		mtx_unlock(&Giant);
5745 		return (error);
5746 	}
5747 
5748 	/* Perform the requested operation. */
5749 	switch (cmd) {
5750 	case DEV_ATTACH:
5751 		if (device_is_attached(dev))
5752 			error = EBUSY;
5753 		else if (!device_is_enabled(dev))
5754 			error = ENXIO;
5755 		else
5756 			error = device_probe_and_attach(dev);
5757 		break;
5758 	case DEV_DETACH:
5759 		if (!device_is_attached(dev)) {
5760 			error = ENXIO;
5761 			break;
5762 		}
5763 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5764 			error = device_quiesce(dev);
5765 			if (error)
5766 				break;
5767 		}
5768 		error = device_detach(dev);
5769 		break;
5770 	case DEV_ENABLE:
5771 		if (device_is_enabled(dev)) {
5772 			error = EBUSY;
5773 			break;
5774 		}
5775 
5776 		/*
5777 		 * If the device has been probed but not attached (e.g.
5778 		 * when it has been disabled by a loader hint), just
5779 		 * attach the device rather than doing a full probe.
5780 		 */
5781 		device_enable(dev);
5782 		if (device_is_alive(dev)) {
5783 			/*
5784 			 * If the device was disabled via a hint, clear
5785 			 * the hint.
5786 			 */
5787 			if (resource_disabled(dev->driver->name, dev->unit))
5788 				resource_unset_value(dev->driver->name,
5789 				    dev->unit, "disabled");
5790 			error = device_attach(dev);
5791 		} else
5792 			error = device_probe_and_attach(dev);
5793 		break;
5794 	case DEV_DISABLE:
5795 		if (!device_is_enabled(dev)) {
5796 			error = ENXIO;
5797 			break;
5798 		}
5799 
5800 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5801 			error = device_quiesce(dev);
5802 			if (error)
5803 				break;
5804 		}
5805 
5806 		/*
5807 		 * Force DF_FIXEDCLASS on around detach to preserve
5808 		 * the existing name.
5809 		 */
5810 		old = dev->flags;
5811 		dev->flags |= DF_FIXEDCLASS;
5812 		error = device_detach(dev);
5813 		if (!(old & DF_FIXEDCLASS))
5814 			dev->flags &= ~DF_FIXEDCLASS;
5815 		if (error == 0)
5816 			device_disable(dev);
5817 		break;
5818 	case DEV_SUSPEND:
5819 		if (device_is_suspended(dev)) {
5820 			error = EBUSY;
5821 			break;
5822 		}
5823 		if (device_get_parent(dev) == NULL) {
5824 			error = EINVAL;
5825 			break;
5826 		}
5827 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5828 		break;
5829 	case DEV_RESUME:
5830 		if (!device_is_suspended(dev)) {
5831 			error = EINVAL;
5832 			break;
5833 		}
5834 		if (device_get_parent(dev) == NULL) {
5835 			error = EINVAL;
5836 			break;
5837 		}
5838 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5839 		break;
5840 	case DEV_SET_DRIVER: {
5841 		devclass_t dc;
5842 		char driver[128];
5843 
5844 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5845 		if (error)
5846 			break;
5847 		if (driver[0] == '\0') {
5848 			error = EINVAL;
5849 			break;
5850 		}
5851 		if (dev->devclass != NULL &&
5852 		    strcmp(driver, dev->devclass->name) == 0)
5853 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5854 			break;
5855 
5856 		/*
5857 		 * Scan drivers for this device's bus looking for at
5858 		 * least one matching driver.
5859 		 */
5860 		if (dev->parent == NULL) {
5861 			error = EINVAL;
5862 			break;
5863 		}
5864 		if (!driver_exists(dev->parent, driver)) {
5865 			error = ENOENT;
5866 			break;
5867 		}
5868 		dc = devclass_create(driver);
5869 		if (dc == NULL) {
5870 			error = ENOMEM;
5871 			break;
5872 		}
5873 
5874 		/* Detach device if necessary. */
5875 		if (device_is_attached(dev)) {
5876 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5877 				error = device_detach(dev);
5878 			else
5879 				error = EBUSY;
5880 			if (error)
5881 				break;
5882 		}
5883 
5884 		/* Clear any previously-fixed device class and unit. */
5885 		if (dev->flags & DF_FIXEDCLASS)
5886 			devclass_delete_device(dev->devclass, dev);
5887 		dev->flags |= DF_WILDCARD;
5888 		dev->unit = -1;
5889 
5890 		/* Force the new device class. */
5891 		error = devclass_add_device(dc, dev);
5892 		if (error)
5893 			break;
5894 		dev->flags |= DF_FIXEDCLASS;
5895 		error = device_probe_and_attach(dev);
5896 		break;
5897 	}
5898 	case DEV_CLEAR_DRIVER:
5899 		if (!(dev->flags & DF_FIXEDCLASS)) {
5900 			error = 0;
5901 			break;
5902 		}
5903 		if (device_is_attached(dev)) {
5904 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5905 				error = device_detach(dev);
5906 			else
5907 				error = EBUSY;
5908 			if (error)
5909 				break;
5910 		}
5911 
5912 		dev->flags &= ~DF_FIXEDCLASS;
5913 		dev->flags |= DF_WILDCARD;
5914 		devclass_delete_device(dev->devclass, dev);
5915 		error = device_probe_and_attach(dev);
5916 		break;
5917 	case DEV_RESCAN:
5918 		if (!device_is_attached(dev)) {
5919 			error = ENXIO;
5920 			break;
5921 		}
5922 		error = BUS_RESCAN(dev);
5923 		break;
5924 	case DEV_DELETE: {
5925 		device_t parent;
5926 
5927 		parent = device_get_parent(dev);
5928 		if (parent == NULL) {
5929 			error = EINVAL;
5930 			break;
5931 		}
5932 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5933 			if (bus_child_present(dev) != 0) {
5934 				error = EBUSY;
5935 				break;
5936 			}
5937 		}
5938 
5939 		error = device_delete_child(parent, dev);
5940 		break;
5941 	}
5942 	case DEV_FREEZE:
5943 		if (device_frozen)
5944 			error = EBUSY;
5945 		else
5946 			device_frozen = true;
5947 		break;
5948 	case DEV_THAW:
5949 		if (!device_frozen)
5950 			error = EBUSY;
5951 		else {
5952 			device_do_deferred_actions();
5953 			device_frozen = false;
5954 		}
5955 		break;
5956 	case DEV_RESET:
5957 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5958 			error = EINVAL;
5959 			break;
5960 		}
5961 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5962 		    req->dr_flags);
5963 		break;
5964 	}
5965 	mtx_unlock(&Giant);
5966 	return (error);
5967 }
5968 
5969 static struct cdevsw devctl2_cdevsw = {
5970 	.d_version =	D_VERSION,
5971 	.d_ioctl =	devctl2_ioctl,
5972 	.d_name =	"devctl2",
5973 };
5974 
5975 static void
5976 devctl2_init(void)
5977 {
5978 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5979 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5980 }
5981 
5982 /*
5983  * APIs to manage deprecation and obsolescence.
5984  */
5985 static int obsolete_panic = 0;
5986 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
5987     "Panic when obsolete features are used (0 = never, 1 = if osbolete, "
5988     "2 = if deprecated)");
5989 
5990 static void
5991 gone_panic(int major, int running, const char *msg)
5992 {
5993 	switch (obsolete_panic)
5994 	{
5995 	case 0:
5996 		return;
5997 	case 1:
5998 		if (running < major)
5999 			return;
6000 		/* FALLTHROUGH */
6001 	default:
6002 		panic("%s", msg);
6003 	}
6004 }
6005 
6006 void
6007 _gone_in(int major, const char *msg)
6008 {
6009 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6010 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6011 		printf("Obsolete code will be removed soon: %s\n", msg);
6012 	else
6013 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6014 		    major, msg);
6015 }
6016 
6017 void
6018 _gone_in_dev(device_t dev, int major, const char *msg)
6019 {
6020 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6021 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6022 		device_printf(dev,
6023 		    "Obsolete code will be removed soon: %s\n", msg);
6024 	else
6025 		device_printf(dev,
6026 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6027 		    major, msg);
6028 }
6029 
6030 #ifdef DDB
6031 DB_SHOW_COMMAND(device, db_show_device)
6032 {
6033 	device_t dev;
6034 
6035 	if (!have_addr)
6036 		return;
6037 
6038 	dev = (device_t)addr;
6039 
6040 	db_printf("name:    %s\n", device_get_nameunit(dev));
6041 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6042 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6043 	db_printf("  addr:    %p\n", dev);
6044 	db_printf("  parent:  %p\n", dev->parent);
6045 	db_printf("  softc:   %p\n", dev->softc);
6046 	db_printf("  ivars:   %p\n", dev->ivars);
6047 }
6048 
6049 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6050 {
6051 	device_t dev;
6052 
6053 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6054 		db_show_device((db_expr_t)dev, true, count, modif);
6055 	}
6056 }
6057 #endif
6058