xref: /freebsd/sys/kern/subr_bus.c (revision 137a344c6341d1469432e9deb3a25593f96672ad)
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/eventhandler.h>
38 #include <sys/filio.h>
39 #include <sys/lock.h>
40 #include <sys/kernel.h>
41 #include <sys/kobj.h>
42 #include <sys/limits.h>
43 #include <sys/malloc.h>
44 #include <sys/module.h>
45 #include <sys/mutex.h>
46 #include <sys/poll.h>
47 #include <sys/priv.h>
48 #include <sys/proc.h>
49 #include <sys/condvar.h>
50 #include <sys/queue.h>
51 #include <machine/bus.h>
52 #include <sys/random.h>
53 #include <sys/rman.h>
54 #include <sys/selinfo.h>
55 #include <sys/signalvar.h>
56 #include <sys/smp.h>
57 #include <sys/sysctl.h>
58 #include <sys/systm.h>
59 #include <sys/uio.h>
60 #include <sys/bus.h>
61 #include <sys/interrupt.h>
62 #include <sys/cpuset.h>
63 
64 #include <net/vnet.h>
65 
66 #include <machine/cpu.h>
67 #include <machine/stdarg.h>
68 
69 #include <vm/uma.h>
70 #include <vm/vm.h>
71 
72 #include <ddb/ddb.h>
73 
74 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW, NULL, NULL);
75 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW, NULL, NULL);
76 
77 /*
78  * Used to attach drivers to devclasses.
79  */
80 typedef struct driverlink *driverlink_t;
81 struct driverlink {
82 	kobj_class_t	driver;
83 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
84 	int		pass;
85 	TAILQ_ENTRY(driverlink) passlink;
86 };
87 
88 /*
89  * Forward declarations
90  */
91 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
92 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
93 typedef TAILQ_HEAD(device_list, device) device_list_t;
94 
95 struct devclass {
96 	TAILQ_ENTRY(devclass) link;
97 	devclass_t	parent;		/* parent in devclass hierarchy */
98 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
99 	char		*name;
100 	device_t	*devices;	/* array of devices indexed by unit */
101 	int		maxunit;	/* size of devices array */
102 	int		flags;
103 #define DC_HAS_CHILDREN		1
104 
105 	struct sysctl_ctx_list sysctl_ctx;
106 	struct sysctl_oid *sysctl_tree;
107 };
108 
109 /**
110  * @brief Implementation of device.
111  */
112 struct device {
113 	/*
114 	 * A device is a kernel object. The first field must be the
115 	 * current ops table for the object.
116 	 */
117 	KOBJ_FIELDS;
118 
119 	/*
120 	 * Device hierarchy.
121 	 */
122 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
123 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
124 	device_t	parent;		/**< parent of this device  */
125 	device_list_t	children;	/**< list of child devices */
126 
127 	/*
128 	 * Details of this device.
129 	 */
130 	driver_t	*driver;	/**< current driver */
131 	devclass_t	devclass;	/**< current device class */
132 	int		unit;		/**< current unit number */
133 	char*		nameunit;	/**< name+unit e.g. foodev0 */
134 	char*		desc;		/**< driver specific description */
135 	int		busy;		/**< count of calls to device_busy() */
136 	device_state_t	state;		/**< current device state  */
137 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
138 	u_int		flags;		/**< internal device flags  */
139 	u_int	order;			/**< order from device_add_child_ordered() */
140 	void	*ivars;			/**< instance variables  */
141 	void	*softc;			/**< current driver's variables  */
142 
143 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
144 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
145 };
146 
147 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
148 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
149 
150 EVENTHANDLER_LIST_DEFINE(device_attach);
151 EVENTHANDLER_LIST_DEFINE(device_detach);
152 EVENTHANDLER_LIST_DEFINE(dev_lookup);
153 
154 static void devctl2_init(void);
155 
156 #define DRIVERNAME(d)	((d)? d->name : "no driver")
157 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
158 
159 #ifdef BUS_DEBUG
160 
161 static int bus_debug = 1;
162 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
163     "Bus debug level");
164 
165 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
166 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
167 
168 /**
169  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
170  * prevent syslog from deleting initial spaces
171  */
172 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
173 
174 static void print_device_short(device_t dev, int indent);
175 static void print_device(device_t dev, int indent);
176 void print_device_tree_short(device_t dev, int indent);
177 void print_device_tree(device_t dev, int indent);
178 static void print_driver_short(driver_t *driver, int indent);
179 static void print_driver(driver_t *driver, int indent);
180 static void print_driver_list(driver_list_t drivers, int indent);
181 static void print_devclass_short(devclass_t dc, int indent);
182 static void print_devclass(devclass_t dc, int indent);
183 void print_devclass_list_short(void);
184 void print_devclass_list(void);
185 
186 #else
187 /* Make the compiler ignore the function calls */
188 #define PDEBUG(a)			/* nop */
189 #define DEVICENAME(d)			/* nop */
190 
191 #define print_device_short(d,i)		/* nop */
192 #define print_device(d,i)		/* nop */
193 #define print_device_tree_short(d,i)	/* nop */
194 #define print_device_tree(d,i)		/* nop */
195 #define print_driver_short(d,i)		/* nop */
196 #define print_driver(d,i)		/* nop */
197 #define print_driver_list(d,i)		/* nop */
198 #define print_devclass_short(d,i)	/* nop */
199 #define print_devclass(d,i)		/* nop */
200 #define print_devclass_list_short()	/* nop */
201 #define print_devclass_list()		/* nop */
202 #endif
203 
204 /*
205  * dev sysctl tree
206  */
207 
208 enum {
209 	DEVCLASS_SYSCTL_PARENT,
210 };
211 
212 static int
213 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
214 {
215 	devclass_t dc = (devclass_t)arg1;
216 	const char *value;
217 
218 	switch (arg2) {
219 	case DEVCLASS_SYSCTL_PARENT:
220 		value = dc->parent ? dc->parent->name : "";
221 		break;
222 	default:
223 		return (EINVAL);
224 	}
225 	return (SYSCTL_OUT_STR(req, value));
226 }
227 
228 static void
229 devclass_sysctl_init(devclass_t dc)
230 {
231 
232 	if (dc->sysctl_tree != NULL)
233 		return;
234 	sysctl_ctx_init(&dc->sysctl_ctx);
235 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
236 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
237 	    CTLFLAG_RD, NULL, "");
238 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
239 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
240 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
241 	    "parent class");
242 }
243 
244 enum {
245 	DEVICE_SYSCTL_DESC,
246 	DEVICE_SYSCTL_DRIVER,
247 	DEVICE_SYSCTL_LOCATION,
248 	DEVICE_SYSCTL_PNPINFO,
249 	DEVICE_SYSCTL_PARENT,
250 };
251 
252 static int
253 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
254 {
255 	device_t dev = (device_t)arg1;
256 	const char *value;
257 	char *buf;
258 	int error;
259 
260 	buf = NULL;
261 	switch (arg2) {
262 	case DEVICE_SYSCTL_DESC:
263 		value = dev->desc ? dev->desc : "";
264 		break;
265 	case DEVICE_SYSCTL_DRIVER:
266 		value = dev->driver ? dev->driver->name : "";
267 		break;
268 	case DEVICE_SYSCTL_LOCATION:
269 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
270 		bus_child_location_str(dev, buf, 1024);
271 		break;
272 	case DEVICE_SYSCTL_PNPINFO:
273 		value = buf = malloc(1024, M_BUS, M_WAITOK | M_ZERO);
274 		bus_child_pnpinfo_str(dev, buf, 1024);
275 		break;
276 	case DEVICE_SYSCTL_PARENT:
277 		value = dev->parent ? dev->parent->nameunit : "";
278 		break;
279 	default:
280 		return (EINVAL);
281 	}
282 	error = SYSCTL_OUT_STR(req, value);
283 	if (buf != NULL)
284 		free(buf, M_BUS);
285 	return (error);
286 }
287 
288 static void
289 device_sysctl_init(device_t dev)
290 {
291 	devclass_t dc = dev->devclass;
292 	int domain;
293 
294 	if (dev->sysctl_tree != NULL)
295 		return;
296 	devclass_sysctl_init(dc);
297 	sysctl_ctx_init(&dev->sysctl_ctx);
298 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
299 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
300 	    dev->nameunit + strlen(dc->name),
301 	    CTLFLAG_RD, NULL, "", "device_index");
302 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
303 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD,
304 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
305 	    "device description");
306 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
307 	    OID_AUTO, "%driver", CTLTYPE_STRING | CTLFLAG_RD,
308 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
309 	    "device driver name");
310 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
311 	    OID_AUTO, "%location", CTLTYPE_STRING | CTLFLAG_RD,
312 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
313 	    "device location relative to parent");
314 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
315 	    OID_AUTO, "%pnpinfo", CTLTYPE_STRING | CTLFLAG_RD,
316 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
317 	    "device identification");
318 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
319 	    OID_AUTO, "%parent", CTLTYPE_STRING | CTLFLAG_RD,
320 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
321 	    "parent device");
322 	if (bus_get_domain(dev, &domain) == 0)
323 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
324 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
325 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
326 }
327 
328 static void
329 device_sysctl_update(device_t dev)
330 {
331 	devclass_t dc = dev->devclass;
332 
333 	if (dev->sysctl_tree == NULL)
334 		return;
335 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
336 }
337 
338 static void
339 device_sysctl_fini(device_t dev)
340 {
341 	if (dev->sysctl_tree == NULL)
342 		return;
343 	sysctl_ctx_free(&dev->sysctl_ctx);
344 	dev->sysctl_tree = NULL;
345 }
346 
347 /*
348  * /dev/devctl implementation
349  */
350 
351 /*
352  * This design allows only one reader for /dev/devctl.  This is not desirable
353  * in the long run, but will get a lot of hair out of this implementation.
354  * Maybe we should make this device a clonable device.
355  *
356  * Also note: we specifically do not attach a device to the device_t tree
357  * to avoid potential chicken and egg problems.  One could argue that all
358  * of this belongs to the root node.  One could also further argue that the
359  * sysctl interface that we have not might more properly be an ioctl
360  * interface, but at this stage of the game, I'm not inclined to rock that
361  * boat.
362  *
363  * I'm also not sure that the SIGIO support is done correctly or not, as
364  * I copied it from a driver that had SIGIO support that likely hasn't been
365  * tested since 3.4 or 2.2.8!
366  */
367 
368 /* Deprecated way to adjust queue length */
369 static int sysctl_devctl_disable(SYSCTL_HANDLER_ARGS);
370 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_disable, CTLTYPE_INT | CTLFLAG_RWTUN |
371     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_disable, "I",
372     "devctl disable -- deprecated");
373 
374 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
375 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
376 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
377 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
378     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
379 
380 static d_open_t		devopen;
381 static d_close_t	devclose;
382 static d_read_t		devread;
383 static d_ioctl_t	devioctl;
384 static d_poll_t		devpoll;
385 static d_kqfilter_t	devkqfilter;
386 
387 static struct cdevsw dev_cdevsw = {
388 	.d_version =	D_VERSION,
389 	.d_open =	devopen,
390 	.d_close =	devclose,
391 	.d_read =	devread,
392 	.d_ioctl =	devioctl,
393 	.d_poll =	devpoll,
394 	.d_kqfilter =	devkqfilter,
395 	.d_name =	"devctl",
396 };
397 
398 struct dev_event_info
399 {
400 	char *dei_data;
401 	TAILQ_ENTRY(dev_event_info) dei_link;
402 };
403 
404 TAILQ_HEAD(devq, dev_event_info);
405 
406 static struct dev_softc
407 {
408 	int	inuse;
409 	int	nonblock;
410 	int	queued;
411 	int	async;
412 	struct mtx mtx;
413 	struct cv cv;
414 	struct selinfo sel;
415 	struct devq devq;
416 	struct sigio *sigio;
417 } devsoftc;
418 
419 static void	filt_devctl_detach(struct knote *kn);
420 static int	filt_devctl_read(struct knote *kn, long hint);
421 
422 struct filterops devctl_rfiltops = {
423 	.f_isfd = 1,
424 	.f_detach = filt_devctl_detach,
425 	.f_event = filt_devctl_read,
426 };
427 
428 static struct cdev *devctl_dev;
429 
430 static void
431 devinit(void)
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 	TAILQ_INIT(&devsoftc.devq);
438 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
439 	devctl2_init();
440 }
441 
442 static int
443 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
444 {
445 
446 	mtx_lock(&devsoftc.mtx);
447 	if (devsoftc.inuse) {
448 		mtx_unlock(&devsoftc.mtx);
449 		return (EBUSY);
450 	}
451 	/* move to init */
452 	devsoftc.inuse = 1;
453 	mtx_unlock(&devsoftc.mtx);
454 	return (0);
455 }
456 
457 static int
458 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
459 {
460 
461 	mtx_lock(&devsoftc.mtx);
462 	devsoftc.inuse = 0;
463 	devsoftc.nonblock = 0;
464 	devsoftc.async = 0;
465 	cv_broadcast(&devsoftc.cv);
466 	funsetown(&devsoftc.sigio);
467 	mtx_unlock(&devsoftc.mtx);
468 	return (0);
469 }
470 
471 /*
472  * The read channel for this device is used to report changes to
473  * userland in realtime.  We are required to free the data as well as
474  * the n1 object because we allocate them separately.  Also note that
475  * we return one record at a time.  If you try to read this device a
476  * character at a time, you will lose the rest of the data.  Listening
477  * programs are expected to cope.
478  */
479 static int
480 devread(struct cdev *dev, struct uio *uio, int ioflag)
481 {
482 	struct dev_event_info *n1;
483 	int rv;
484 
485 	mtx_lock(&devsoftc.mtx);
486 	while (TAILQ_EMPTY(&devsoftc.devq)) {
487 		if (devsoftc.nonblock) {
488 			mtx_unlock(&devsoftc.mtx);
489 			return (EAGAIN);
490 		}
491 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
492 		if (rv) {
493 			/*
494 			 * Need to translate ERESTART to EINTR here? -- jake
495 			 */
496 			mtx_unlock(&devsoftc.mtx);
497 			return (rv);
498 		}
499 	}
500 	n1 = TAILQ_FIRST(&devsoftc.devq);
501 	TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
502 	devsoftc.queued--;
503 	mtx_unlock(&devsoftc.mtx);
504 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
505 	free(n1->dei_data, M_BUS);
506 	free(n1, M_BUS);
507 	return (rv);
508 }
509 
510 static	int
511 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
512 {
513 	switch (cmd) {
514 
515 	case FIONBIO:
516 		if (*(int*)data)
517 			devsoftc.nonblock = 1;
518 		else
519 			devsoftc.nonblock = 0;
520 		return (0);
521 	case FIOASYNC:
522 		if (*(int*)data)
523 			devsoftc.async = 1;
524 		else
525 			devsoftc.async = 0;
526 		return (0);
527 	case FIOSETOWN:
528 		return fsetown(*(int *)data, &devsoftc.sigio);
529 	case FIOGETOWN:
530 		*(int *)data = fgetown(&devsoftc.sigio);
531 		return (0);
532 
533 		/* (un)Support for other fcntl() calls. */
534 	case FIOCLEX:
535 	case FIONCLEX:
536 	case FIONREAD:
537 	default:
538 		break;
539 	}
540 	return (ENOTTY);
541 }
542 
543 static	int
544 devpoll(struct cdev *dev, int events, struct thread *td)
545 {
546 	int	revents = 0;
547 
548 	mtx_lock(&devsoftc.mtx);
549 	if (events & (POLLIN | POLLRDNORM)) {
550 		if (!TAILQ_EMPTY(&devsoftc.devq))
551 			revents = events & (POLLIN | POLLRDNORM);
552 		else
553 			selrecord(td, &devsoftc.sel);
554 	}
555 	mtx_unlock(&devsoftc.mtx);
556 
557 	return (revents);
558 }
559 
560 static int
561 devkqfilter(struct cdev *dev, struct knote *kn)
562 {
563 	int error;
564 
565 	if (kn->kn_filter == EVFILT_READ) {
566 		kn->kn_fop = &devctl_rfiltops;
567 		knlist_add(&devsoftc.sel.si_note, kn, 0);
568 		error = 0;
569 	} else
570 		error = EINVAL;
571 	return (error);
572 }
573 
574 static void
575 filt_devctl_detach(struct knote *kn)
576 {
577 
578 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
579 }
580 
581 static int
582 filt_devctl_read(struct knote *kn, long hint)
583 {
584 	kn->kn_data = devsoftc.queued;
585 	return (kn->kn_data != 0);
586 }
587 
588 /**
589  * @brief Return whether the userland process is running
590  */
591 boolean_t
592 devctl_process_running(void)
593 {
594 	return (devsoftc.inuse == 1);
595 }
596 
597 /**
598  * @brief Queue data to be read from the devctl device
599  *
600  * Generic interface to queue data to the devctl device.  It is
601  * assumed that @p data is properly formatted.  It is further assumed
602  * that @p data is allocated using the M_BUS malloc type.
603  */
604 void
605 devctl_queue_data_f(char *data, int flags)
606 {
607 	struct dev_event_info *n1 = NULL, *n2 = NULL;
608 
609 	if (strlen(data) == 0)
610 		goto out;
611 	if (devctl_queue_length == 0)
612 		goto out;
613 	n1 = malloc(sizeof(*n1), M_BUS, flags);
614 	if (n1 == NULL)
615 		goto out;
616 	n1->dei_data = data;
617 	mtx_lock(&devsoftc.mtx);
618 	if (devctl_queue_length == 0) {
619 		mtx_unlock(&devsoftc.mtx);
620 		free(n1->dei_data, M_BUS);
621 		free(n1, M_BUS);
622 		return;
623 	}
624 	/* Leave at least one spot in the queue... */
625 	while (devsoftc.queued > devctl_queue_length - 1) {
626 		n2 = TAILQ_FIRST(&devsoftc.devq);
627 		TAILQ_REMOVE(&devsoftc.devq, n2, dei_link);
628 		free(n2->dei_data, M_BUS);
629 		free(n2, M_BUS);
630 		devsoftc.queued--;
631 	}
632 	TAILQ_INSERT_TAIL(&devsoftc.devq, n1, dei_link);
633 	devsoftc.queued++;
634 	cv_broadcast(&devsoftc.cv);
635 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
636 	mtx_unlock(&devsoftc.mtx);
637 	selwakeup(&devsoftc.sel);
638 	if (devsoftc.async && devsoftc.sigio != NULL)
639 		pgsigio(&devsoftc.sigio, SIGIO, 0);
640 	return;
641 out:
642 	/*
643 	 * We have to free data on all error paths since the caller
644 	 * assumes it will be free'd when this item is dequeued.
645 	 */
646 	free(data, M_BUS);
647 	return;
648 }
649 
650 void
651 devctl_queue_data(char *data)
652 {
653 
654 	devctl_queue_data_f(data, M_NOWAIT);
655 }
656 
657 /**
658  * @brief Send a 'notification' to userland, using standard ways
659  */
660 void
661 devctl_notify_f(const char *system, const char *subsystem, const char *type,
662     const char *data, int flags)
663 {
664 	int len = 0;
665 	char *msg;
666 
667 	if (system == NULL)
668 		return;		/* BOGUS!  Must specify system. */
669 	if (subsystem == NULL)
670 		return;		/* BOGUS!  Must specify subsystem. */
671 	if (type == NULL)
672 		return;		/* BOGUS!  Must specify type. */
673 	len += strlen(" system=") + strlen(system);
674 	len += strlen(" subsystem=") + strlen(subsystem);
675 	len += strlen(" type=") + strlen(type);
676 	/* add in the data message plus newline. */
677 	if (data != NULL)
678 		len += strlen(data);
679 	len += 3;	/* '!', '\n', and NUL */
680 	msg = malloc(len, M_BUS, flags);
681 	if (msg == NULL)
682 		return;		/* Drop it on the floor */
683 	if (data != NULL)
684 		snprintf(msg, len, "!system=%s subsystem=%s type=%s %s\n",
685 		    system, subsystem, type, data);
686 	else
687 		snprintf(msg, len, "!system=%s subsystem=%s type=%s\n",
688 		    system, subsystem, type);
689 	devctl_queue_data_f(msg, flags);
690 }
691 
692 void
693 devctl_notify(const char *system, const char *subsystem, const char *type,
694     const char *data)
695 {
696 
697 	devctl_notify_f(system, subsystem, type, data, M_NOWAIT);
698 }
699 
700 /*
701  * Common routine that tries to make sending messages as easy as possible.
702  * We allocate memory for the data, copy strings into that, but do not
703  * free it unless there's an error.  The dequeue part of the driver should
704  * free the data.  We don't send data when the device is disabled.  We do
705  * send data, even when we have no listeners, because we wish to avoid
706  * races relating to startup and restart of listening applications.
707  *
708  * devaddq is designed to string together the type of event, with the
709  * object of that event, plus the plug and play info and location info
710  * for that event.  This is likely most useful for devices, but less
711  * useful for other consumers of this interface.  Those should use
712  * the devctl_queue_data() interface instead.
713  */
714 static void
715 devaddq(const char *type, const char *what, device_t dev)
716 {
717 	char *data = NULL;
718 	char *loc = NULL;
719 	char *pnp = NULL;
720 	const char *parstr;
721 
722 	if (!devctl_queue_length)/* Rare race, but lost races safely discard */
723 		return;
724 	data = malloc(1024, M_BUS, M_NOWAIT);
725 	if (data == NULL)
726 		goto bad;
727 
728 	/* get the bus specific location of this device */
729 	loc = malloc(1024, M_BUS, M_NOWAIT);
730 	if (loc == NULL)
731 		goto bad;
732 	*loc = '\0';
733 	bus_child_location_str(dev, loc, 1024);
734 
735 	/* Get the bus specific pnp info of this device */
736 	pnp = malloc(1024, M_BUS, M_NOWAIT);
737 	if (pnp == NULL)
738 		goto bad;
739 	*pnp = '\0';
740 	bus_child_pnpinfo_str(dev, pnp, 1024);
741 
742 	/* Get the parent of this device, or / if high enough in the tree. */
743 	if (device_get_parent(dev) == NULL)
744 		parstr = ".";	/* Or '/' ? */
745 	else
746 		parstr = device_get_nameunit(device_get_parent(dev));
747 	/* String it all together. */
748 	snprintf(data, 1024, "%s%s at %s %s on %s\n", type, what, loc, pnp,
749 	  parstr);
750 	free(loc, M_BUS);
751 	free(pnp, M_BUS);
752 	devctl_queue_data(data);
753 	return;
754 bad:
755 	free(pnp, M_BUS);
756 	free(loc, M_BUS);
757 	free(data, M_BUS);
758 	return;
759 }
760 
761 /*
762  * A device was added to the tree.  We are called just after it successfully
763  * attaches (that is, probe and attach success for this device).  No call
764  * is made if a device is merely parented into the tree.  See devnomatch
765  * if probe fails.  If attach fails, no notification is sent (but maybe
766  * we should have a different message for this).
767  */
768 static void
769 devadded(device_t dev)
770 {
771 	devaddq("+", device_get_nameunit(dev), dev);
772 }
773 
774 /*
775  * A device was removed from the tree.  We are called just before this
776  * happens.
777  */
778 static void
779 devremoved(device_t dev)
780 {
781 	devaddq("-", device_get_nameunit(dev), dev);
782 }
783 
784 /*
785  * Called when there's no match for this device.  This is only called
786  * the first time that no match happens, so we don't keep getting this
787  * message.  Should that prove to be undesirable, we can change it.
788  * This is called when all drivers that can attach to a given bus
789  * decline to accept this device.  Other errors may not be detected.
790  */
791 static void
792 devnomatch(device_t dev)
793 {
794 	devaddq("?", "", dev);
795 }
796 
797 static int
798 sysctl_devctl_disable(SYSCTL_HANDLER_ARGS)
799 {
800 	struct dev_event_info *n1;
801 	int dis, error;
802 
803 	dis = (devctl_queue_length == 0);
804 	error = sysctl_handle_int(oidp, &dis, 0, req);
805 	if (error || !req->newptr)
806 		return (error);
807 	if (mtx_initialized(&devsoftc.mtx))
808 		mtx_lock(&devsoftc.mtx);
809 	if (dis) {
810 		while (!TAILQ_EMPTY(&devsoftc.devq)) {
811 			n1 = TAILQ_FIRST(&devsoftc.devq);
812 			TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
813 			free(n1->dei_data, M_BUS);
814 			free(n1, M_BUS);
815 		}
816 		devsoftc.queued = 0;
817 		devctl_queue_length = 0;
818 	} else {
819 		devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
820 	}
821 	if (mtx_initialized(&devsoftc.mtx))
822 		mtx_unlock(&devsoftc.mtx);
823 	return (0);
824 }
825 
826 static int
827 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
828 {
829 	struct dev_event_info *n1;
830 	int q, error;
831 
832 	q = devctl_queue_length;
833 	error = sysctl_handle_int(oidp, &q, 0, req);
834 	if (error || !req->newptr)
835 		return (error);
836 	if (q < 0)
837 		return (EINVAL);
838 	if (mtx_initialized(&devsoftc.mtx))
839 		mtx_lock(&devsoftc.mtx);
840 	devctl_queue_length = q;
841 	while (devsoftc.queued > devctl_queue_length) {
842 		n1 = TAILQ_FIRST(&devsoftc.devq);
843 		TAILQ_REMOVE(&devsoftc.devq, n1, dei_link);
844 		free(n1->dei_data, M_BUS);
845 		free(n1, M_BUS);
846 		devsoftc.queued--;
847 	}
848 	if (mtx_initialized(&devsoftc.mtx))
849 		mtx_unlock(&devsoftc.mtx);
850 	return (0);
851 }
852 
853 /**
854  * @brief safely quotes strings that might have double quotes in them.
855  *
856  * The devctl protocol relies on quoted strings having matching quotes.
857  * This routine quotes any internal quotes so the resulting string
858  * is safe to pass to snprintf to construct, for example pnp info strings.
859  * Strings are always terminated with a NUL, but may be truncated if longer
860  * than @p len bytes after quotes.
861  *
862  * @param dst	Buffer to hold the string. Must be at least @p len bytes long
863  * @param src	Original buffer.
864  * @param len	Length of buffer pointed to by @dst, including trailing NUL
865  */
866 void
867 devctl_safe_quote(char *dst, const char *src, size_t len)
868 {
869 	char *walker = dst, *ep = dst + len - 1;
870 
871 	if (len == 0)
872 		return;
873 	while (src != NULL && walker < ep)
874 	{
875 		if (*src == '"' || *src == '\\') {
876 			if (ep - walker < 2)
877 				break;
878 			*walker++ = '\\';
879 		}
880 		*walker++ = *src++;
881 	}
882 	*walker = '\0';
883 }
884 
885 /* End of /dev/devctl code */
886 
887 static TAILQ_HEAD(,device)	bus_data_devices;
888 static int bus_data_generation = 1;
889 
890 static kobj_method_t null_methods[] = {
891 	KOBJMETHOD_END
892 };
893 
894 DEFINE_CLASS(null, null_methods, 0);
895 
896 /*
897  * Bus pass implementation
898  */
899 
900 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
901 int bus_current_pass = BUS_PASS_ROOT;
902 
903 /**
904  * @internal
905  * @brief Register the pass level of a new driver attachment
906  *
907  * Register a new driver attachment's pass level.  If no driver
908  * attachment with the same pass level has been added, then @p new
909  * will be added to the global passes list.
910  *
911  * @param new		the new driver attachment
912  */
913 static void
914 driver_register_pass(struct driverlink *new)
915 {
916 	struct driverlink *dl;
917 
918 	/* We only consider pass numbers during boot. */
919 	if (bus_current_pass == BUS_PASS_DEFAULT)
920 		return;
921 
922 	/*
923 	 * Walk the passes list.  If we already know about this pass
924 	 * then there is nothing to do.  If we don't, then insert this
925 	 * driver link into the list.
926 	 */
927 	TAILQ_FOREACH(dl, &passes, passlink) {
928 		if (dl->pass < new->pass)
929 			continue;
930 		if (dl->pass == new->pass)
931 			return;
932 		TAILQ_INSERT_BEFORE(dl, new, passlink);
933 		return;
934 	}
935 	TAILQ_INSERT_TAIL(&passes, new, passlink);
936 }
937 
938 /**
939  * @brief Raise the current bus pass
940  *
941  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
942  * method on the root bus to kick off a new device tree scan for each
943  * new pass level that has at least one driver.
944  */
945 void
946 bus_set_pass(int pass)
947 {
948 	struct driverlink *dl;
949 
950 	if (bus_current_pass > pass)
951 		panic("Attempt to lower bus pass level");
952 
953 	TAILQ_FOREACH(dl, &passes, passlink) {
954 		/* Skip pass values below the current pass level. */
955 		if (dl->pass <= bus_current_pass)
956 			continue;
957 
958 		/*
959 		 * Bail once we hit a driver with a pass level that is
960 		 * too high.
961 		 */
962 		if (dl->pass > pass)
963 			break;
964 
965 		/*
966 		 * Raise the pass level to the next level and rescan
967 		 * the tree.
968 		 */
969 		bus_current_pass = dl->pass;
970 		BUS_NEW_PASS(root_bus);
971 	}
972 
973 	/*
974 	 * If there isn't a driver registered for the requested pass,
975 	 * then bus_current_pass might still be less than 'pass'.  Set
976 	 * it to 'pass' in that case.
977 	 */
978 	if (bus_current_pass < pass)
979 		bus_current_pass = pass;
980 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
981 }
982 
983 /*
984  * Devclass implementation
985  */
986 
987 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
988 
989 /**
990  * @internal
991  * @brief Find or create a device class
992  *
993  * If a device class with the name @p classname exists, return it,
994  * otherwise if @p create is non-zero create and return a new device
995  * class.
996  *
997  * If @p parentname is non-NULL, the parent of the devclass is set to
998  * the devclass of that name.
999  *
1000  * @param classname	the devclass name to find or create
1001  * @param parentname	the parent devclass name or @c NULL
1002  * @param create	non-zero to create a devclass
1003  */
1004 static devclass_t
1005 devclass_find_internal(const char *classname, const char *parentname,
1006 		       int create)
1007 {
1008 	devclass_t dc;
1009 
1010 	PDEBUG(("looking for %s", classname));
1011 	if (!classname)
1012 		return (NULL);
1013 
1014 	TAILQ_FOREACH(dc, &devclasses, link) {
1015 		if (!strcmp(dc->name, classname))
1016 			break;
1017 	}
1018 
1019 	if (create && !dc) {
1020 		PDEBUG(("creating %s", classname));
1021 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1022 		    M_BUS, M_NOWAIT | M_ZERO);
1023 		if (!dc)
1024 			return (NULL);
1025 		dc->parent = NULL;
1026 		dc->name = (char*) (dc + 1);
1027 		strcpy(dc->name, classname);
1028 		TAILQ_INIT(&dc->drivers);
1029 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1030 
1031 		bus_data_generation_update();
1032 	}
1033 
1034 	/*
1035 	 * If a parent class is specified, then set that as our parent so
1036 	 * that this devclass will support drivers for the parent class as
1037 	 * well.  If the parent class has the same name don't do this though
1038 	 * as it creates a cycle that can trigger an infinite loop in
1039 	 * device_probe_child() if a device exists for which there is no
1040 	 * suitable driver.
1041 	 */
1042 	if (parentname && dc && !dc->parent &&
1043 	    strcmp(classname, parentname) != 0) {
1044 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1045 		dc->parent->flags |= DC_HAS_CHILDREN;
1046 	}
1047 
1048 	return (dc);
1049 }
1050 
1051 /**
1052  * @brief Create a device class
1053  *
1054  * If a device class with the name @p classname exists, return it,
1055  * otherwise create and return a new device class.
1056  *
1057  * @param classname	the devclass name to find or create
1058  */
1059 devclass_t
1060 devclass_create(const char *classname)
1061 {
1062 	return (devclass_find_internal(classname, NULL, TRUE));
1063 }
1064 
1065 /**
1066  * @brief Find a device class
1067  *
1068  * If a device class with the name @p classname exists, return it,
1069  * otherwise return @c NULL.
1070  *
1071  * @param classname	the devclass name to find
1072  */
1073 devclass_t
1074 devclass_find(const char *classname)
1075 {
1076 	return (devclass_find_internal(classname, NULL, FALSE));
1077 }
1078 
1079 /**
1080  * @brief Register that a device driver has been added to a devclass
1081  *
1082  * Register that a device driver has been added to a devclass.  This
1083  * is called by devclass_add_driver to accomplish the recursive
1084  * notification of all the children classes of dc, as well as dc.
1085  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1086  * the devclass.
1087  *
1088  * We do a full search here of the devclass list at each iteration
1089  * level to save storing children-lists in the devclass structure.  If
1090  * we ever move beyond a few dozen devices doing this, we may need to
1091  * reevaluate...
1092  *
1093  * @param dc		the devclass to edit
1094  * @param driver	the driver that was just added
1095  */
1096 static void
1097 devclass_driver_added(devclass_t dc, driver_t *driver)
1098 {
1099 	devclass_t parent;
1100 	int i;
1101 
1102 	/*
1103 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1104 	 */
1105 	for (i = 0; i < dc->maxunit; i++)
1106 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1107 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1108 
1109 	/*
1110 	 * Walk through the children classes.  Since we only keep a
1111 	 * single parent pointer around, we walk the entire list of
1112 	 * devclasses looking for children.  We set the
1113 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1114 	 * the parent, so we only walk the list for those devclasses
1115 	 * that have children.
1116 	 */
1117 	if (!(dc->flags & DC_HAS_CHILDREN))
1118 		return;
1119 	parent = dc;
1120 	TAILQ_FOREACH(dc, &devclasses, link) {
1121 		if (dc->parent == parent)
1122 			devclass_driver_added(dc, driver);
1123 	}
1124 }
1125 
1126 /**
1127  * @brief Add a device driver to a device class
1128  *
1129  * Add a device driver to a devclass. This is normally called
1130  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1131  * all devices in the devclass will be called to allow them to attempt
1132  * to re-probe any unmatched children.
1133  *
1134  * @param dc		the devclass to edit
1135  * @param driver	the driver to register
1136  */
1137 int
1138 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1139 {
1140 	driverlink_t dl;
1141 	const char *parentname;
1142 
1143 	PDEBUG(("%s", DRIVERNAME(driver)));
1144 
1145 	/* Don't allow invalid pass values. */
1146 	if (pass <= BUS_PASS_ROOT)
1147 		return (EINVAL);
1148 
1149 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1150 	if (!dl)
1151 		return (ENOMEM);
1152 
1153 	/*
1154 	 * Compile the driver's methods. Also increase the reference count
1155 	 * so that the class doesn't get freed when the last instance
1156 	 * goes. This means we can safely use static methods and avoids a
1157 	 * double-free in devclass_delete_driver.
1158 	 */
1159 	kobj_class_compile((kobj_class_t) driver);
1160 
1161 	/*
1162 	 * If the driver has any base classes, make the
1163 	 * devclass inherit from the devclass of the driver's
1164 	 * first base class. This will allow the system to
1165 	 * search for drivers in both devclasses for children
1166 	 * of a device using this driver.
1167 	 */
1168 	if (driver->baseclasses)
1169 		parentname = driver->baseclasses[0]->name;
1170 	else
1171 		parentname = NULL;
1172 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1173 
1174 	dl->driver = driver;
1175 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1176 	driver->refs++;		/* XXX: kobj_mtx */
1177 	dl->pass = pass;
1178 	driver_register_pass(dl);
1179 
1180 	devclass_driver_added(dc, driver);
1181 	bus_data_generation_update();
1182 	return (0);
1183 }
1184 
1185 /**
1186  * @brief Register that a device driver has been deleted from a devclass
1187  *
1188  * Register that a device driver has been removed from a devclass.
1189  * This is called by devclass_delete_driver to accomplish the
1190  * recursive notification of all the children classes of busclass, as
1191  * well as busclass.  Each layer will attempt to detach the driver
1192  * from any devices that are children of the bus's devclass.  The function
1193  * will return an error if a device fails to detach.
1194  *
1195  * We do a full search here of the devclass list at each iteration
1196  * level to save storing children-lists in the devclass structure.  If
1197  * we ever move beyond a few dozen devices doing this, we may need to
1198  * reevaluate...
1199  *
1200  * @param busclass	the devclass of the parent bus
1201  * @param dc		the devclass of the driver being deleted
1202  * @param driver	the driver being deleted
1203  */
1204 static int
1205 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1206 {
1207 	devclass_t parent;
1208 	device_t dev;
1209 	int error, i;
1210 
1211 	/*
1212 	 * Disassociate from any devices.  We iterate through all the
1213 	 * devices in the devclass of the driver and detach any which are
1214 	 * using the driver and which have a parent in the devclass which
1215 	 * we are deleting from.
1216 	 *
1217 	 * Note that since a driver can be in multiple devclasses, we
1218 	 * should not detach devices which are not children of devices in
1219 	 * the affected devclass.
1220 	 */
1221 	for (i = 0; i < dc->maxunit; i++) {
1222 		if (dc->devices[i]) {
1223 			dev = dc->devices[i];
1224 			if (dev->driver == driver && dev->parent &&
1225 			    dev->parent->devclass == busclass) {
1226 				if ((error = device_detach(dev)) != 0)
1227 					return (error);
1228 				BUS_PROBE_NOMATCH(dev->parent, dev);
1229 				devnomatch(dev);
1230 				dev->flags |= DF_DONENOMATCH;
1231 			}
1232 		}
1233 	}
1234 
1235 	/*
1236 	 * Walk through the children classes.  Since we only keep a
1237 	 * single parent pointer around, we walk the entire list of
1238 	 * devclasses looking for children.  We set the
1239 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1240 	 * the parent, so we only walk the list for those devclasses
1241 	 * that have children.
1242 	 */
1243 	if (!(busclass->flags & DC_HAS_CHILDREN))
1244 		return (0);
1245 	parent = busclass;
1246 	TAILQ_FOREACH(busclass, &devclasses, link) {
1247 		if (busclass->parent == parent) {
1248 			error = devclass_driver_deleted(busclass, dc, driver);
1249 			if (error)
1250 				return (error);
1251 		}
1252 	}
1253 	return (0);
1254 }
1255 
1256 /**
1257  * @brief Delete a device driver from a device class
1258  *
1259  * Delete a device driver from a devclass. This is normally called
1260  * automatically by DRIVER_MODULE().
1261  *
1262  * If the driver is currently attached to any devices,
1263  * devclass_delete_driver() will first attempt to detach from each
1264  * device. If one of the detach calls fails, the driver will not be
1265  * deleted.
1266  *
1267  * @param dc		the devclass to edit
1268  * @param driver	the driver to unregister
1269  */
1270 int
1271 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1272 {
1273 	devclass_t dc = devclass_find(driver->name);
1274 	driverlink_t dl;
1275 	int error;
1276 
1277 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1278 
1279 	if (!dc)
1280 		return (0);
1281 
1282 	/*
1283 	 * Find the link structure in the bus' list of drivers.
1284 	 */
1285 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1286 		if (dl->driver == driver)
1287 			break;
1288 	}
1289 
1290 	if (!dl) {
1291 		PDEBUG(("%s not found in %s list", driver->name,
1292 		    busclass->name));
1293 		return (ENOENT);
1294 	}
1295 
1296 	error = devclass_driver_deleted(busclass, dc, driver);
1297 	if (error != 0)
1298 		return (error);
1299 
1300 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1301 	free(dl, M_BUS);
1302 
1303 	/* XXX: kobj_mtx */
1304 	driver->refs--;
1305 	if (driver->refs == 0)
1306 		kobj_class_free((kobj_class_t) driver);
1307 
1308 	bus_data_generation_update();
1309 	return (0);
1310 }
1311 
1312 /**
1313  * @brief Quiesces a set of device drivers from a device class
1314  *
1315  * Quiesce a device driver from a devclass. This is normally called
1316  * automatically by DRIVER_MODULE().
1317  *
1318  * If the driver is currently attached to any devices,
1319  * devclass_quiesece_driver() will first attempt to quiesce each
1320  * device.
1321  *
1322  * @param dc		the devclass to edit
1323  * @param driver	the driver to unregister
1324  */
1325 static int
1326 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1327 {
1328 	devclass_t dc = devclass_find(driver->name);
1329 	driverlink_t dl;
1330 	device_t dev;
1331 	int i;
1332 	int error;
1333 
1334 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1335 
1336 	if (!dc)
1337 		return (0);
1338 
1339 	/*
1340 	 * Find the link structure in the bus' list of drivers.
1341 	 */
1342 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1343 		if (dl->driver == driver)
1344 			break;
1345 	}
1346 
1347 	if (!dl) {
1348 		PDEBUG(("%s not found in %s list", driver->name,
1349 		    busclass->name));
1350 		return (ENOENT);
1351 	}
1352 
1353 	/*
1354 	 * Quiesce all devices.  We iterate through all the devices in
1355 	 * the devclass of the driver and quiesce any which are using
1356 	 * the driver and which have a parent in the devclass which we
1357 	 * are quiescing.
1358 	 *
1359 	 * Note that since a driver can be in multiple devclasses, we
1360 	 * should not quiesce devices which are not children of
1361 	 * devices in the affected devclass.
1362 	 */
1363 	for (i = 0; i < dc->maxunit; i++) {
1364 		if (dc->devices[i]) {
1365 			dev = dc->devices[i];
1366 			if (dev->driver == driver && dev->parent &&
1367 			    dev->parent->devclass == busclass) {
1368 				if ((error = device_quiesce(dev)) != 0)
1369 					return (error);
1370 			}
1371 		}
1372 	}
1373 
1374 	return (0);
1375 }
1376 
1377 /**
1378  * @internal
1379  */
1380 static driverlink_t
1381 devclass_find_driver_internal(devclass_t dc, const char *classname)
1382 {
1383 	driverlink_t dl;
1384 
1385 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1386 
1387 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1388 		if (!strcmp(dl->driver->name, classname))
1389 			return (dl);
1390 	}
1391 
1392 	PDEBUG(("not found"));
1393 	return (NULL);
1394 }
1395 
1396 /**
1397  * @brief Return the name of the devclass
1398  */
1399 const char *
1400 devclass_get_name(devclass_t dc)
1401 {
1402 	return (dc->name);
1403 }
1404 
1405 /**
1406  * @brief Find a device given a unit number
1407  *
1408  * @param dc		the devclass to search
1409  * @param unit		the unit number to search for
1410  *
1411  * @returns		the device with the given unit number or @c
1412  *			NULL if there is no such device
1413  */
1414 device_t
1415 devclass_get_device(devclass_t dc, int unit)
1416 {
1417 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1418 		return (NULL);
1419 	return (dc->devices[unit]);
1420 }
1421 
1422 /**
1423  * @brief Find the softc field of a device given a unit number
1424  *
1425  * @param dc		the devclass to search
1426  * @param unit		the unit number to search for
1427  *
1428  * @returns		the softc field of the device with the given
1429  *			unit number or @c NULL if there is no such
1430  *			device
1431  */
1432 void *
1433 devclass_get_softc(devclass_t dc, int unit)
1434 {
1435 	device_t dev;
1436 
1437 	dev = devclass_get_device(dc, unit);
1438 	if (!dev)
1439 		return (NULL);
1440 
1441 	return (device_get_softc(dev));
1442 }
1443 
1444 /**
1445  * @brief Get a list of devices in the devclass
1446  *
1447  * An array containing a list of all the devices in the given devclass
1448  * is allocated and returned in @p *devlistp. The number of devices
1449  * in the array is returned in @p *devcountp. The caller should free
1450  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1451  *
1452  * @param dc		the devclass to examine
1453  * @param devlistp	points at location for array pointer return
1454  *			value
1455  * @param devcountp	points at location for array size return value
1456  *
1457  * @retval 0		success
1458  * @retval ENOMEM	the array allocation failed
1459  */
1460 int
1461 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1462 {
1463 	int count, i;
1464 	device_t *list;
1465 
1466 	count = devclass_get_count(dc);
1467 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1468 	if (!list)
1469 		return (ENOMEM);
1470 
1471 	count = 0;
1472 	for (i = 0; i < dc->maxunit; i++) {
1473 		if (dc->devices[i]) {
1474 			list[count] = dc->devices[i];
1475 			count++;
1476 		}
1477 	}
1478 
1479 	*devlistp = list;
1480 	*devcountp = count;
1481 
1482 	return (0);
1483 }
1484 
1485 /**
1486  * @brief Get a list of drivers in the devclass
1487  *
1488  * An array containing a list of pointers to all the drivers in the
1489  * given devclass is allocated and returned in @p *listp.  The number
1490  * of drivers in the array is returned in @p *countp. The caller should
1491  * free the array using @c free(p, M_TEMP).
1492  *
1493  * @param dc		the devclass to examine
1494  * @param listp		gives location for array pointer return value
1495  * @param countp	gives location for number of array elements
1496  *			return value
1497  *
1498  * @retval 0		success
1499  * @retval ENOMEM	the array allocation failed
1500  */
1501 int
1502 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1503 {
1504 	driverlink_t dl;
1505 	driver_t **list;
1506 	int count;
1507 
1508 	count = 0;
1509 	TAILQ_FOREACH(dl, &dc->drivers, link)
1510 		count++;
1511 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1512 	if (list == NULL)
1513 		return (ENOMEM);
1514 
1515 	count = 0;
1516 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1517 		list[count] = dl->driver;
1518 		count++;
1519 	}
1520 	*listp = list;
1521 	*countp = count;
1522 
1523 	return (0);
1524 }
1525 
1526 /**
1527  * @brief Get the number of devices in a devclass
1528  *
1529  * @param dc		the devclass to examine
1530  */
1531 int
1532 devclass_get_count(devclass_t dc)
1533 {
1534 	int count, i;
1535 
1536 	count = 0;
1537 	for (i = 0; i < dc->maxunit; i++)
1538 		if (dc->devices[i])
1539 			count++;
1540 	return (count);
1541 }
1542 
1543 /**
1544  * @brief Get the maximum unit number used in a devclass
1545  *
1546  * Note that this is one greater than the highest currently-allocated
1547  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1548  * that not even the devclass has been allocated yet.
1549  *
1550  * @param dc		the devclass to examine
1551  */
1552 int
1553 devclass_get_maxunit(devclass_t dc)
1554 {
1555 	if (dc == NULL)
1556 		return (-1);
1557 	return (dc->maxunit);
1558 }
1559 
1560 /**
1561  * @brief Find a free unit number in a devclass
1562  *
1563  * This function searches for the first unused unit number greater
1564  * that or equal to @p unit.
1565  *
1566  * @param dc		the devclass to examine
1567  * @param unit		the first unit number to check
1568  */
1569 int
1570 devclass_find_free_unit(devclass_t dc, int unit)
1571 {
1572 	if (dc == NULL)
1573 		return (unit);
1574 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1575 		unit++;
1576 	return (unit);
1577 }
1578 
1579 /**
1580  * @brief Set the parent of a devclass
1581  *
1582  * The parent class is normally initialised automatically by
1583  * DRIVER_MODULE().
1584  *
1585  * @param dc		the devclass to edit
1586  * @param pdc		the new parent devclass
1587  */
1588 void
1589 devclass_set_parent(devclass_t dc, devclass_t pdc)
1590 {
1591 	dc->parent = pdc;
1592 }
1593 
1594 /**
1595  * @brief Get the parent of a devclass
1596  *
1597  * @param dc		the devclass to examine
1598  */
1599 devclass_t
1600 devclass_get_parent(devclass_t dc)
1601 {
1602 	return (dc->parent);
1603 }
1604 
1605 struct sysctl_ctx_list *
1606 devclass_get_sysctl_ctx(devclass_t dc)
1607 {
1608 	return (&dc->sysctl_ctx);
1609 }
1610 
1611 struct sysctl_oid *
1612 devclass_get_sysctl_tree(devclass_t dc)
1613 {
1614 	return (dc->sysctl_tree);
1615 }
1616 
1617 /**
1618  * @internal
1619  * @brief Allocate a unit number
1620  *
1621  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1622  * will do). The allocated unit number is returned in @p *unitp.
1623 
1624  * @param dc		the devclass to allocate from
1625  * @param unitp		points at the location for the allocated unit
1626  *			number
1627  *
1628  * @retval 0		success
1629  * @retval EEXIST	the requested unit number is already allocated
1630  * @retval ENOMEM	memory allocation failure
1631  */
1632 static int
1633 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1634 {
1635 	const char *s;
1636 	int unit = *unitp;
1637 
1638 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1639 
1640 	/* Ask the parent bus if it wants to wire this device. */
1641 	if (unit == -1)
1642 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1643 		    &unit);
1644 
1645 	/* If we were given a wired unit number, check for existing device */
1646 	/* XXX imp XXX */
1647 	if (unit != -1) {
1648 		if (unit >= 0 && unit < dc->maxunit &&
1649 		    dc->devices[unit] != NULL) {
1650 			if (bootverbose)
1651 				printf("%s: %s%d already exists; skipping it\n",
1652 				    dc->name, dc->name, *unitp);
1653 			return (EEXIST);
1654 		}
1655 	} else {
1656 		/* Unwired device, find the next available slot for it */
1657 		unit = 0;
1658 		for (unit = 0;; unit++) {
1659 			/* If there is an "at" hint for a unit then skip it. */
1660 			if (resource_string_value(dc->name, unit, "at", &s) ==
1661 			    0)
1662 				continue;
1663 
1664 			/* If this device slot is already in use, skip it. */
1665 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1666 				continue;
1667 
1668 			break;
1669 		}
1670 	}
1671 
1672 	/*
1673 	 * We've selected a unit beyond the length of the table, so let's
1674 	 * extend the table to make room for all units up to and including
1675 	 * this one.
1676 	 */
1677 	if (unit >= dc->maxunit) {
1678 		device_t *newlist, *oldlist;
1679 		int newsize;
1680 
1681 		oldlist = dc->devices;
1682 		newsize = roundup((unit + 1), MINALLOCSIZE / sizeof(device_t));
1683 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1684 		if (!newlist)
1685 			return (ENOMEM);
1686 		if (oldlist != NULL)
1687 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1688 		bzero(newlist + dc->maxunit,
1689 		    sizeof(device_t) * (newsize - dc->maxunit));
1690 		dc->devices = newlist;
1691 		dc->maxunit = newsize;
1692 		if (oldlist != NULL)
1693 			free(oldlist, M_BUS);
1694 	}
1695 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1696 
1697 	*unitp = unit;
1698 	return (0);
1699 }
1700 
1701 /**
1702  * @internal
1703  * @brief Add a device to a devclass
1704  *
1705  * A unit number is allocated for the device (using the device's
1706  * preferred unit number if any) and the device is registered in the
1707  * devclass. This allows the device to be looked up by its unit
1708  * number, e.g. by decoding a dev_t minor number.
1709  *
1710  * @param dc		the devclass to add to
1711  * @param dev		the device to add
1712  *
1713  * @retval 0		success
1714  * @retval EEXIST	the requested unit number is already allocated
1715  * @retval ENOMEM	memory allocation failure
1716  */
1717 static int
1718 devclass_add_device(devclass_t dc, device_t dev)
1719 {
1720 	int buflen, error;
1721 
1722 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1723 
1724 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1725 	if (buflen < 0)
1726 		return (ENOMEM);
1727 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1728 	if (!dev->nameunit)
1729 		return (ENOMEM);
1730 
1731 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1732 		free(dev->nameunit, M_BUS);
1733 		dev->nameunit = NULL;
1734 		return (error);
1735 	}
1736 	dc->devices[dev->unit] = dev;
1737 	dev->devclass = dc;
1738 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1739 
1740 	return (0);
1741 }
1742 
1743 /**
1744  * @internal
1745  * @brief Delete a device from a devclass
1746  *
1747  * The device is removed from the devclass's device list and its unit
1748  * number is freed.
1749 
1750  * @param dc		the devclass to delete from
1751  * @param dev		the device to delete
1752  *
1753  * @retval 0		success
1754  */
1755 static int
1756 devclass_delete_device(devclass_t dc, device_t dev)
1757 {
1758 	if (!dc || !dev)
1759 		return (0);
1760 
1761 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1762 
1763 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1764 		panic("devclass_delete_device: inconsistent device class");
1765 	dc->devices[dev->unit] = NULL;
1766 	if (dev->flags & DF_WILDCARD)
1767 		dev->unit = -1;
1768 	dev->devclass = NULL;
1769 	free(dev->nameunit, M_BUS);
1770 	dev->nameunit = NULL;
1771 
1772 	return (0);
1773 }
1774 
1775 /**
1776  * @internal
1777  * @brief Make a new device and add it as a child of @p parent
1778  *
1779  * @param parent	the parent of the new device
1780  * @param name		the devclass name of the new device or @c NULL
1781  *			to leave the devclass unspecified
1782  * @parem unit		the unit number of the new device of @c -1 to
1783  *			leave the unit number unspecified
1784  *
1785  * @returns the new device
1786  */
1787 static device_t
1788 make_device(device_t parent, const char *name, int unit)
1789 {
1790 	device_t dev;
1791 	devclass_t dc;
1792 
1793 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1794 
1795 	if (name) {
1796 		dc = devclass_find_internal(name, NULL, TRUE);
1797 		if (!dc) {
1798 			printf("make_device: can't find device class %s\n",
1799 			    name);
1800 			return (NULL);
1801 		}
1802 	} else {
1803 		dc = NULL;
1804 	}
1805 
1806 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1807 	if (!dev)
1808 		return (NULL);
1809 
1810 	dev->parent = parent;
1811 	TAILQ_INIT(&dev->children);
1812 	kobj_init((kobj_t) dev, &null_class);
1813 	dev->driver = NULL;
1814 	dev->devclass = NULL;
1815 	dev->unit = unit;
1816 	dev->nameunit = NULL;
1817 	dev->desc = NULL;
1818 	dev->busy = 0;
1819 	dev->devflags = 0;
1820 	dev->flags = DF_ENABLED;
1821 	dev->order = 0;
1822 	if (unit == -1)
1823 		dev->flags |= DF_WILDCARD;
1824 	if (name) {
1825 		dev->flags |= DF_FIXEDCLASS;
1826 		if (devclass_add_device(dc, dev)) {
1827 			kobj_delete((kobj_t) dev, M_BUS);
1828 			return (NULL);
1829 		}
1830 	}
1831 	dev->ivars = NULL;
1832 	dev->softc = NULL;
1833 
1834 	dev->state = DS_NOTPRESENT;
1835 
1836 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1837 	bus_data_generation_update();
1838 
1839 	return (dev);
1840 }
1841 
1842 /**
1843  * @internal
1844  * @brief Print a description of a device.
1845  */
1846 static int
1847 device_print_child(device_t dev, device_t child)
1848 {
1849 	int retval = 0;
1850 
1851 	if (device_is_alive(child))
1852 		retval += BUS_PRINT_CHILD(dev, child);
1853 	else
1854 		retval += device_printf(child, " not found\n");
1855 
1856 	return (retval);
1857 }
1858 
1859 /**
1860  * @brief Create a new device
1861  *
1862  * This creates a new device and adds it as a child of an existing
1863  * parent device. The new device will be added after the last existing
1864  * child with order zero.
1865  *
1866  * @param dev		the device which will be the parent of the
1867  *			new child device
1868  * @param name		devclass name for new device or @c NULL if not
1869  *			specified
1870  * @param unit		unit number for new device or @c -1 if not
1871  *			specified
1872  *
1873  * @returns		the new device
1874  */
1875 device_t
1876 device_add_child(device_t dev, const char *name, int unit)
1877 {
1878 	return (device_add_child_ordered(dev, 0, name, unit));
1879 }
1880 
1881 /**
1882  * @brief Create a new device
1883  *
1884  * This creates a new device and adds it as a child of an existing
1885  * parent device. The new device will be added after the last existing
1886  * child with the same order.
1887  *
1888  * @param dev		the device which will be the parent of the
1889  *			new child device
1890  * @param order		a value which is used to partially sort the
1891  *			children of @p dev - devices created using
1892  *			lower values of @p order appear first in @p
1893  *			dev's list of children
1894  * @param name		devclass name for new device or @c NULL if not
1895  *			specified
1896  * @param unit		unit number for new device or @c -1 if not
1897  *			specified
1898  *
1899  * @returns		the new device
1900  */
1901 device_t
1902 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1903 {
1904 	device_t child;
1905 	device_t place;
1906 
1907 	PDEBUG(("%s at %s with order %u as unit %d",
1908 	    name, DEVICENAME(dev), order, unit));
1909 	KASSERT(name != NULL || unit == -1,
1910 	    ("child device with wildcard name and specific unit number"));
1911 
1912 	child = make_device(dev, name, unit);
1913 	if (child == NULL)
1914 		return (child);
1915 	child->order = order;
1916 
1917 	TAILQ_FOREACH(place, &dev->children, link) {
1918 		if (place->order > order)
1919 			break;
1920 	}
1921 
1922 	if (place) {
1923 		/*
1924 		 * The device 'place' is the first device whose order is
1925 		 * greater than the new child.
1926 		 */
1927 		TAILQ_INSERT_BEFORE(place, child, link);
1928 	} else {
1929 		/*
1930 		 * The new child's order is greater or equal to the order of
1931 		 * any existing device. Add the child to the tail of the list.
1932 		 */
1933 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1934 	}
1935 
1936 	bus_data_generation_update();
1937 	return (child);
1938 }
1939 
1940 /**
1941  * @brief Delete a device
1942  *
1943  * This function deletes a device along with all of its children. If
1944  * the device currently has a driver attached to it, the device is
1945  * detached first using device_detach().
1946  *
1947  * @param dev		the parent device
1948  * @param child		the device to delete
1949  *
1950  * @retval 0		success
1951  * @retval non-zero	a unit error code describing the error
1952  */
1953 int
1954 device_delete_child(device_t dev, device_t child)
1955 {
1956 	int error;
1957 	device_t grandchild;
1958 
1959 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1960 
1961 	/* detach parent before deleting children, if any */
1962 	if ((error = device_detach(child)) != 0)
1963 		return (error);
1964 
1965 	/* remove children second */
1966 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1967 		error = device_delete_child(child, grandchild);
1968 		if (error)
1969 			return (error);
1970 	}
1971 
1972 	if (child->devclass)
1973 		devclass_delete_device(child->devclass, child);
1974 	if (child->parent)
1975 		BUS_CHILD_DELETED(dev, child);
1976 	TAILQ_REMOVE(&dev->children, child, link);
1977 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1978 	kobj_delete((kobj_t) child, M_BUS);
1979 
1980 	bus_data_generation_update();
1981 	return (0);
1982 }
1983 
1984 /**
1985  * @brief Delete all children devices of the given device, if any.
1986  *
1987  * This function deletes all children devices of the given device, if
1988  * any, using the device_delete_child() function for each device it
1989  * finds. If a child device cannot be deleted, this function will
1990  * return an error code.
1991  *
1992  * @param dev		the parent device
1993  *
1994  * @retval 0		success
1995  * @retval non-zero	a device would not detach
1996  */
1997 int
1998 device_delete_children(device_t dev)
1999 {
2000 	device_t child;
2001 	int error;
2002 
2003 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2004 
2005 	error = 0;
2006 
2007 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2008 		error = device_delete_child(dev, child);
2009 		if (error) {
2010 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2011 			break;
2012 		}
2013 	}
2014 	return (error);
2015 }
2016 
2017 /**
2018  * @brief Find a device given a unit number
2019  *
2020  * This is similar to devclass_get_devices() but only searches for
2021  * devices which have @p dev as a parent.
2022  *
2023  * @param dev		the parent device to search
2024  * @param unit		the unit number to search for.  If the unit is -1,
2025  *			return the first child of @p dev which has name
2026  *			@p classname (that is, the one with the lowest unit.)
2027  *
2028  * @returns		the device with the given unit number or @c
2029  *			NULL if there is no such device
2030  */
2031 device_t
2032 device_find_child(device_t dev, const char *classname, int unit)
2033 {
2034 	devclass_t dc;
2035 	device_t child;
2036 
2037 	dc = devclass_find(classname);
2038 	if (!dc)
2039 		return (NULL);
2040 
2041 	if (unit != -1) {
2042 		child = devclass_get_device(dc, unit);
2043 		if (child && child->parent == dev)
2044 			return (child);
2045 	} else {
2046 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2047 			child = devclass_get_device(dc, unit);
2048 			if (child && child->parent == dev)
2049 				return (child);
2050 		}
2051 	}
2052 	return (NULL);
2053 }
2054 
2055 /**
2056  * @internal
2057  */
2058 static driverlink_t
2059 first_matching_driver(devclass_t dc, device_t dev)
2060 {
2061 	if (dev->devclass)
2062 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2063 	return (TAILQ_FIRST(&dc->drivers));
2064 }
2065 
2066 /**
2067  * @internal
2068  */
2069 static driverlink_t
2070 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2071 {
2072 	if (dev->devclass) {
2073 		driverlink_t dl;
2074 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2075 			if (!strcmp(dev->devclass->name, dl->driver->name))
2076 				return (dl);
2077 		return (NULL);
2078 	}
2079 	return (TAILQ_NEXT(last, link));
2080 }
2081 
2082 /**
2083  * @internal
2084  */
2085 int
2086 device_probe_child(device_t dev, device_t child)
2087 {
2088 	devclass_t dc;
2089 	driverlink_t best = NULL;
2090 	driverlink_t dl;
2091 	int result, pri = 0;
2092 	int hasclass = (child->devclass != NULL);
2093 
2094 	GIANT_REQUIRED;
2095 
2096 	dc = dev->devclass;
2097 	if (!dc)
2098 		panic("device_probe_child: parent device has no devclass");
2099 
2100 	/*
2101 	 * If the state is already probed, then return.  However, don't
2102 	 * return if we can rebid this object.
2103 	 */
2104 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2105 		return (0);
2106 
2107 	for (; dc; dc = dc->parent) {
2108 		for (dl = first_matching_driver(dc, child);
2109 		     dl;
2110 		     dl = next_matching_driver(dc, child, dl)) {
2111 			/* If this driver's pass is too high, then ignore it. */
2112 			if (dl->pass > bus_current_pass)
2113 				continue;
2114 
2115 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2116 			result = device_set_driver(child, dl->driver);
2117 			if (result == ENOMEM)
2118 				return (result);
2119 			else if (result != 0)
2120 				continue;
2121 			if (!hasclass) {
2122 				if (device_set_devclass(child,
2123 				    dl->driver->name) != 0) {
2124 					char const * devname =
2125 					    device_get_name(child);
2126 					if (devname == NULL)
2127 						devname = "(unknown)";
2128 					printf("driver bug: Unable to set "
2129 					    "devclass (class: %s "
2130 					    "devname: %s)\n",
2131 					    dl->driver->name,
2132 					    devname);
2133 					(void)device_set_driver(child, NULL);
2134 					continue;
2135 				}
2136 			}
2137 
2138 			/* Fetch any flags for the device before probing. */
2139 			resource_int_value(dl->driver->name, child->unit,
2140 			    "flags", &child->devflags);
2141 
2142 			result = DEVICE_PROBE(child);
2143 
2144 			/* Reset flags and devclass before the next probe. */
2145 			child->devflags = 0;
2146 			if (!hasclass)
2147 				(void)device_set_devclass(child, NULL);
2148 
2149 			/*
2150 			 * If the driver returns SUCCESS, there can be
2151 			 * no higher match for this device.
2152 			 */
2153 			if (result == 0) {
2154 				best = dl;
2155 				pri = 0;
2156 				break;
2157 			}
2158 
2159 			/*
2160 			 * Reset DF_QUIET in case this driver doesn't
2161 			 * end up as the best driver.
2162 			 */
2163 			device_verbose(child);
2164 
2165 			/*
2166 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2167 			 * only match on devices whose driver was explicitly
2168 			 * specified.
2169 			 */
2170 			if (result <= BUS_PROBE_NOWILDCARD &&
2171 			    !(child->flags & DF_FIXEDCLASS)) {
2172 				result = ENXIO;
2173 			}
2174 
2175 			/*
2176 			 * The driver returned an error so it
2177 			 * certainly doesn't match.
2178 			 */
2179 			if (result > 0) {
2180 				(void)device_set_driver(child, NULL);
2181 				continue;
2182 			}
2183 
2184 			/*
2185 			 * A priority lower than SUCCESS, remember the
2186 			 * best matching driver. Initialise the value
2187 			 * of pri for the first match.
2188 			 */
2189 			if (best == NULL || result > pri) {
2190 				best = dl;
2191 				pri = result;
2192 				continue;
2193 			}
2194 		}
2195 		/*
2196 		 * If we have an unambiguous match in this devclass,
2197 		 * don't look in the parent.
2198 		 */
2199 		if (best && pri == 0)
2200 			break;
2201 	}
2202 
2203 	/*
2204 	 * If we found a driver, change state and initialise the devclass.
2205 	 */
2206 	/* XXX What happens if we rebid and got no best? */
2207 	if (best) {
2208 		/*
2209 		 * If this device was attached, and we were asked to
2210 		 * rescan, and it is a different driver, then we have
2211 		 * to detach the old driver and reattach this new one.
2212 		 * Note, we don't have to check for DF_REBID here
2213 		 * because if the state is > DS_ALIVE, we know it must
2214 		 * be.
2215 		 *
2216 		 * This assumes that all DF_REBID drivers can have
2217 		 * their probe routine called at any time and that
2218 		 * they are idempotent as well as completely benign in
2219 		 * normal operations.
2220 		 *
2221 		 * We also have to make sure that the detach
2222 		 * succeeded, otherwise we fail the operation (or
2223 		 * maybe it should just fail silently?  I'm torn).
2224 		 */
2225 		if (child->state > DS_ALIVE && best->driver != child->driver)
2226 			if ((result = device_detach(dev)) != 0)
2227 				return (result);
2228 
2229 		/* Set the winning driver, devclass, and flags. */
2230 		if (!child->devclass) {
2231 			result = device_set_devclass(child, best->driver->name);
2232 			if (result != 0)
2233 				return (result);
2234 		}
2235 		result = device_set_driver(child, best->driver);
2236 		if (result != 0)
2237 			return (result);
2238 		resource_int_value(best->driver->name, child->unit,
2239 		    "flags", &child->devflags);
2240 
2241 		if (pri < 0) {
2242 			/*
2243 			 * A bit bogus. Call the probe method again to make
2244 			 * sure that we have the right description.
2245 			 */
2246 			DEVICE_PROBE(child);
2247 #if 0
2248 			child->flags |= DF_REBID;
2249 #endif
2250 		} else
2251 			child->flags &= ~DF_REBID;
2252 		child->state = DS_ALIVE;
2253 
2254 		bus_data_generation_update();
2255 		return (0);
2256 	}
2257 
2258 	return (ENXIO);
2259 }
2260 
2261 /**
2262  * @brief Return the parent of a device
2263  */
2264 device_t
2265 device_get_parent(device_t dev)
2266 {
2267 	return (dev->parent);
2268 }
2269 
2270 /**
2271  * @brief Get a list of children of a device
2272  *
2273  * An array containing a list of all the children of the given device
2274  * is allocated and returned in @p *devlistp. The number of devices
2275  * in the array is returned in @p *devcountp. The caller should free
2276  * the array using @c free(p, M_TEMP).
2277  *
2278  * @param dev		the device to examine
2279  * @param devlistp	points at location for array pointer return
2280  *			value
2281  * @param devcountp	points at location for array size return value
2282  *
2283  * @retval 0		success
2284  * @retval ENOMEM	the array allocation failed
2285  */
2286 int
2287 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2288 {
2289 	int count;
2290 	device_t child;
2291 	device_t *list;
2292 
2293 	count = 0;
2294 	TAILQ_FOREACH(child, &dev->children, link) {
2295 		count++;
2296 	}
2297 	if (count == 0) {
2298 		*devlistp = NULL;
2299 		*devcountp = 0;
2300 		return (0);
2301 	}
2302 
2303 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2304 	if (!list)
2305 		return (ENOMEM);
2306 
2307 	count = 0;
2308 	TAILQ_FOREACH(child, &dev->children, link) {
2309 		list[count] = child;
2310 		count++;
2311 	}
2312 
2313 	*devlistp = list;
2314 	*devcountp = count;
2315 
2316 	return (0);
2317 }
2318 
2319 /**
2320  * @brief Return the current driver for the device or @c NULL if there
2321  * is no driver currently attached
2322  */
2323 driver_t *
2324 device_get_driver(device_t dev)
2325 {
2326 	return (dev->driver);
2327 }
2328 
2329 /**
2330  * @brief Return the current devclass for the device or @c NULL if
2331  * there is none.
2332  */
2333 devclass_t
2334 device_get_devclass(device_t dev)
2335 {
2336 	return (dev->devclass);
2337 }
2338 
2339 /**
2340  * @brief Return the name of the device's devclass or @c NULL if there
2341  * is none.
2342  */
2343 const char *
2344 device_get_name(device_t dev)
2345 {
2346 	if (dev != NULL && dev->devclass)
2347 		return (devclass_get_name(dev->devclass));
2348 	return (NULL);
2349 }
2350 
2351 /**
2352  * @brief Return a string containing the device's devclass name
2353  * followed by an ascii representation of the device's unit number
2354  * (e.g. @c "foo2").
2355  */
2356 const char *
2357 device_get_nameunit(device_t dev)
2358 {
2359 	return (dev->nameunit);
2360 }
2361 
2362 /**
2363  * @brief Return the device's unit number.
2364  */
2365 int
2366 device_get_unit(device_t dev)
2367 {
2368 	return (dev->unit);
2369 }
2370 
2371 /**
2372  * @brief Return the device's description string
2373  */
2374 const char *
2375 device_get_desc(device_t dev)
2376 {
2377 	return (dev->desc);
2378 }
2379 
2380 /**
2381  * @brief Return the device's flags
2382  */
2383 uint32_t
2384 device_get_flags(device_t dev)
2385 {
2386 	return (dev->devflags);
2387 }
2388 
2389 struct sysctl_ctx_list *
2390 device_get_sysctl_ctx(device_t dev)
2391 {
2392 	return (&dev->sysctl_ctx);
2393 }
2394 
2395 struct sysctl_oid *
2396 device_get_sysctl_tree(device_t dev)
2397 {
2398 	return (dev->sysctl_tree);
2399 }
2400 
2401 /**
2402  * @brief Print the name of the device followed by a colon and a space
2403  *
2404  * @returns the number of characters printed
2405  */
2406 int
2407 device_print_prettyname(device_t dev)
2408 {
2409 	const char *name = device_get_name(dev);
2410 
2411 	if (name == NULL)
2412 		return (printf("unknown: "));
2413 	return (printf("%s%d: ", name, device_get_unit(dev)));
2414 }
2415 
2416 /**
2417  * @brief Print the name of the device followed by a colon, a space
2418  * and the result of calling vprintf() with the value of @p fmt and
2419  * the following arguments.
2420  *
2421  * @returns the number of characters printed
2422  */
2423 int
2424 device_printf(device_t dev, const char * fmt, ...)
2425 {
2426 	va_list ap;
2427 	int retval;
2428 
2429 	retval = device_print_prettyname(dev);
2430 	va_start(ap, fmt);
2431 	retval += vprintf(fmt, ap);
2432 	va_end(ap);
2433 	return (retval);
2434 }
2435 
2436 /**
2437  * @internal
2438  */
2439 static void
2440 device_set_desc_internal(device_t dev, const char* desc, int copy)
2441 {
2442 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2443 		free(dev->desc, M_BUS);
2444 		dev->flags &= ~DF_DESCMALLOCED;
2445 		dev->desc = NULL;
2446 	}
2447 
2448 	if (copy && desc) {
2449 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2450 		if (dev->desc) {
2451 			strcpy(dev->desc, desc);
2452 			dev->flags |= DF_DESCMALLOCED;
2453 		}
2454 	} else {
2455 		/* Avoid a -Wcast-qual warning */
2456 		dev->desc = (char *)(uintptr_t) desc;
2457 	}
2458 
2459 	bus_data_generation_update();
2460 }
2461 
2462 /**
2463  * @brief Set the device's description
2464  *
2465  * The value of @c desc should be a string constant that will not
2466  * change (at least until the description is changed in a subsequent
2467  * call to device_set_desc() or device_set_desc_copy()).
2468  */
2469 void
2470 device_set_desc(device_t dev, const char* desc)
2471 {
2472 	device_set_desc_internal(dev, desc, FALSE);
2473 }
2474 
2475 /**
2476  * @brief Set the device's description
2477  *
2478  * The string pointed to by @c desc is copied. Use this function if
2479  * the device description is generated, (e.g. with sprintf()).
2480  */
2481 void
2482 device_set_desc_copy(device_t dev, const char* desc)
2483 {
2484 	device_set_desc_internal(dev, desc, TRUE);
2485 }
2486 
2487 /**
2488  * @brief Set the device's flags
2489  */
2490 void
2491 device_set_flags(device_t dev, uint32_t flags)
2492 {
2493 	dev->devflags = flags;
2494 }
2495 
2496 /**
2497  * @brief Return the device's softc field
2498  *
2499  * The softc is allocated and zeroed when a driver is attached, based
2500  * on the size field of the driver.
2501  */
2502 void *
2503 device_get_softc(device_t dev)
2504 {
2505 	return (dev->softc);
2506 }
2507 
2508 /**
2509  * @brief Set the device's softc field
2510  *
2511  * Most drivers do not need to use this since the softc is allocated
2512  * automatically when the driver is attached.
2513  */
2514 void
2515 device_set_softc(device_t dev, void *softc)
2516 {
2517 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2518 		free(dev->softc, M_BUS_SC);
2519 	dev->softc = softc;
2520 	if (dev->softc)
2521 		dev->flags |= DF_EXTERNALSOFTC;
2522 	else
2523 		dev->flags &= ~DF_EXTERNALSOFTC;
2524 }
2525 
2526 /**
2527  * @brief Free claimed softc
2528  *
2529  * Most drivers do not need to use this since the softc is freed
2530  * automatically when the driver is detached.
2531  */
2532 void
2533 device_free_softc(void *softc)
2534 {
2535 	free(softc, M_BUS_SC);
2536 }
2537 
2538 /**
2539  * @brief Claim softc
2540  *
2541  * This function can be used to let the driver free the automatically
2542  * allocated softc using "device_free_softc()". This function is
2543  * useful when the driver is refcounting the softc and the softc
2544  * cannot be freed when the "device_detach" method is called.
2545  */
2546 void
2547 device_claim_softc(device_t dev)
2548 {
2549 	if (dev->softc)
2550 		dev->flags |= DF_EXTERNALSOFTC;
2551 	else
2552 		dev->flags &= ~DF_EXTERNALSOFTC;
2553 }
2554 
2555 /**
2556  * @brief Get the device's ivars field
2557  *
2558  * The ivars field is used by the parent device to store per-device
2559  * state (e.g. the physical location of the device or a list of
2560  * resources).
2561  */
2562 void *
2563 device_get_ivars(device_t dev)
2564 {
2565 
2566 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2567 	return (dev->ivars);
2568 }
2569 
2570 /**
2571  * @brief Set the device's ivars field
2572  */
2573 void
2574 device_set_ivars(device_t dev, void * ivars)
2575 {
2576 
2577 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2578 	dev->ivars = ivars;
2579 }
2580 
2581 /**
2582  * @brief Return the device's state
2583  */
2584 device_state_t
2585 device_get_state(device_t dev)
2586 {
2587 	return (dev->state);
2588 }
2589 
2590 /**
2591  * @brief Set the DF_ENABLED flag for the device
2592  */
2593 void
2594 device_enable(device_t dev)
2595 {
2596 	dev->flags |= DF_ENABLED;
2597 }
2598 
2599 /**
2600  * @brief Clear the DF_ENABLED flag for the device
2601  */
2602 void
2603 device_disable(device_t dev)
2604 {
2605 	dev->flags &= ~DF_ENABLED;
2606 }
2607 
2608 /**
2609  * @brief Increment the busy counter for the device
2610  */
2611 void
2612 device_busy(device_t dev)
2613 {
2614 	if (dev->state < DS_ATTACHING)
2615 		panic("device_busy: called for unattached device");
2616 	if (dev->busy == 0 && dev->parent)
2617 		device_busy(dev->parent);
2618 	dev->busy++;
2619 	if (dev->state == DS_ATTACHED)
2620 		dev->state = DS_BUSY;
2621 }
2622 
2623 /**
2624  * @brief Decrement the busy counter for the device
2625  */
2626 void
2627 device_unbusy(device_t dev)
2628 {
2629 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2630 	    dev->state != DS_ATTACHING)
2631 		panic("device_unbusy: called for non-busy device %s",
2632 		    device_get_nameunit(dev));
2633 	dev->busy--;
2634 	if (dev->busy == 0) {
2635 		if (dev->parent)
2636 			device_unbusy(dev->parent);
2637 		if (dev->state == DS_BUSY)
2638 			dev->state = DS_ATTACHED;
2639 	}
2640 }
2641 
2642 /**
2643  * @brief Set the DF_QUIET flag for the device
2644  */
2645 void
2646 device_quiet(device_t dev)
2647 {
2648 	dev->flags |= DF_QUIET;
2649 }
2650 
2651 /**
2652  * @brief Clear the DF_QUIET flag for the device
2653  */
2654 void
2655 device_verbose(device_t dev)
2656 {
2657 	dev->flags &= ~DF_QUIET;
2658 }
2659 
2660 /**
2661  * @brief Return non-zero if the DF_QUIET flag is set on the device
2662  */
2663 int
2664 device_is_quiet(device_t dev)
2665 {
2666 	return ((dev->flags & DF_QUIET) != 0);
2667 }
2668 
2669 /**
2670  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2671  */
2672 int
2673 device_is_enabled(device_t dev)
2674 {
2675 	return ((dev->flags & DF_ENABLED) != 0);
2676 }
2677 
2678 /**
2679  * @brief Return non-zero if the device was successfully probed
2680  */
2681 int
2682 device_is_alive(device_t dev)
2683 {
2684 	return (dev->state >= DS_ALIVE);
2685 }
2686 
2687 /**
2688  * @brief Return non-zero if the device currently has a driver
2689  * attached to it
2690  */
2691 int
2692 device_is_attached(device_t dev)
2693 {
2694 	return (dev->state >= DS_ATTACHED);
2695 }
2696 
2697 /**
2698  * @brief Return non-zero if the device is currently suspended.
2699  */
2700 int
2701 device_is_suspended(device_t dev)
2702 {
2703 	return ((dev->flags & DF_SUSPENDED) != 0);
2704 }
2705 
2706 /**
2707  * @brief Set the devclass of a device
2708  * @see devclass_add_device().
2709  */
2710 int
2711 device_set_devclass(device_t dev, const char *classname)
2712 {
2713 	devclass_t dc;
2714 	int error;
2715 
2716 	if (!classname) {
2717 		if (dev->devclass)
2718 			devclass_delete_device(dev->devclass, dev);
2719 		return (0);
2720 	}
2721 
2722 	if (dev->devclass) {
2723 		printf("device_set_devclass: device class already set\n");
2724 		return (EINVAL);
2725 	}
2726 
2727 	dc = devclass_find_internal(classname, NULL, TRUE);
2728 	if (!dc)
2729 		return (ENOMEM);
2730 
2731 	error = devclass_add_device(dc, dev);
2732 
2733 	bus_data_generation_update();
2734 	return (error);
2735 }
2736 
2737 /**
2738  * @brief Set the devclass of a device and mark the devclass fixed.
2739  * @see device_set_devclass()
2740  */
2741 int
2742 device_set_devclass_fixed(device_t dev, const char *classname)
2743 {
2744 	int error;
2745 
2746 	if (classname == NULL)
2747 		return (EINVAL);
2748 
2749 	error = device_set_devclass(dev, classname);
2750 	if (error)
2751 		return (error);
2752 	dev->flags |= DF_FIXEDCLASS;
2753 	return (0);
2754 }
2755 
2756 /**
2757  * @brief Set the driver of a device
2758  *
2759  * @retval 0		success
2760  * @retval EBUSY	the device already has a driver attached
2761  * @retval ENOMEM	a memory allocation failure occurred
2762  */
2763 int
2764 device_set_driver(device_t dev, driver_t *driver)
2765 {
2766 	if (dev->state >= DS_ATTACHED)
2767 		return (EBUSY);
2768 
2769 	if (dev->driver == driver)
2770 		return (0);
2771 
2772 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2773 		free(dev->softc, M_BUS_SC);
2774 		dev->softc = NULL;
2775 	}
2776 	device_set_desc(dev, NULL);
2777 	kobj_delete((kobj_t) dev, NULL);
2778 	dev->driver = driver;
2779 	if (driver) {
2780 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2781 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2782 			dev->softc = malloc(driver->size, M_BUS_SC,
2783 			    M_NOWAIT | M_ZERO);
2784 			if (!dev->softc) {
2785 				kobj_delete((kobj_t) dev, NULL);
2786 				kobj_init((kobj_t) dev, &null_class);
2787 				dev->driver = NULL;
2788 				return (ENOMEM);
2789 			}
2790 		}
2791 	} else {
2792 		kobj_init((kobj_t) dev, &null_class);
2793 	}
2794 
2795 	bus_data_generation_update();
2796 	return (0);
2797 }
2798 
2799 /**
2800  * @brief Probe a device, and return this status.
2801  *
2802  * This function is the core of the device autoconfiguration
2803  * system. Its purpose is to select a suitable driver for a device and
2804  * then call that driver to initialise the hardware appropriately. The
2805  * driver is selected by calling the DEVICE_PROBE() method of a set of
2806  * candidate drivers and then choosing the driver which returned the
2807  * best value. This driver is then attached to the device using
2808  * device_attach().
2809  *
2810  * The set of suitable drivers is taken from the list of drivers in
2811  * the parent device's devclass. If the device was originally created
2812  * with a specific class name (see device_add_child()), only drivers
2813  * with that name are probed, otherwise all drivers in the devclass
2814  * are probed. If no drivers return successful probe values in the
2815  * parent devclass, the search continues in the parent of that
2816  * devclass (see devclass_get_parent()) if any.
2817  *
2818  * @param dev		the device to initialise
2819  *
2820  * @retval 0		success
2821  * @retval ENXIO	no driver was found
2822  * @retval ENOMEM	memory allocation failure
2823  * @retval non-zero	some other unix error code
2824  * @retval -1		Device already attached
2825  */
2826 int
2827 device_probe(device_t dev)
2828 {
2829 	int error;
2830 
2831 	GIANT_REQUIRED;
2832 
2833 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2834 		return (-1);
2835 
2836 	if (!(dev->flags & DF_ENABLED)) {
2837 		if (bootverbose && device_get_name(dev) != NULL) {
2838 			device_print_prettyname(dev);
2839 			printf("not probed (disabled)\n");
2840 		}
2841 		return (-1);
2842 	}
2843 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2844 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2845 		    !(dev->flags & DF_DONENOMATCH)) {
2846 			BUS_PROBE_NOMATCH(dev->parent, dev);
2847 			devnomatch(dev);
2848 			dev->flags |= DF_DONENOMATCH;
2849 		}
2850 		return (error);
2851 	}
2852 	return (0);
2853 }
2854 
2855 /**
2856  * @brief Probe a device and attach a driver if possible
2857  *
2858  * calls device_probe() and attaches if that was successful.
2859  */
2860 int
2861 device_probe_and_attach(device_t dev)
2862 {
2863 	int error;
2864 
2865 	GIANT_REQUIRED;
2866 
2867 	error = device_probe(dev);
2868 	if (error == -1)
2869 		return (0);
2870 	else if (error != 0)
2871 		return (error);
2872 
2873 	CURVNET_SET_QUIET(vnet0);
2874 	error = device_attach(dev);
2875 	CURVNET_RESTORE();
2876 	return error;
2877 }
2878 
2879 /**
2880  * @brief Attach a device driver to a device
2881  *
2882  * This function is a wrapper around the DEVICE_ATTACH() driver
2883  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2884  * device's sysctl tree, optionally prints a description of the device
2885  * and queues a notification event for user-based device management
2886  * services.
2887  *
2888  * Normally this function is only called internally from
2889  * device_probe_and_attach().
2890  *
2891  * @param dev		the device to initialise
2892  *
2893  * @retval 0		success
2894  * @retval ENXIO	no driver was found
2895  * @retval ENOMEM	memory allocation failure
2896  * @retval non-zero	some other unix error code
2897  */
2898 int
2899 device_attach(device_t dev)
2900 {
2901 	uint64_t attachtime;
2902 	int error;
2903 
2904 	if (resource_disabled(dev->driver->name, dev->unit)) {
2905 		device_disable(dev);
2906 		if (bootverbose)
2907 			 device_printf(dev, "disabled via hints entry\n");
2908 		return (ENXIO);
2909 	}
2910 
2911 	device_sysctl_init(dev);
2912 	if (!device_is_quiet(dev))
2913 		device_print_child(dev->parent, dev);
2914 	attachtime = get_cyclecount();
2915 	dev->state = DS_ATTACHING;
2916 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2917 		printf("device_attach: %s%d attach returned %d\n",
2918 		    dev->driver->name, dev->unit, error);
2919 		if (!(dev->flags & DF_FIXEDCLASS))
2920 			devclass_delete_device(dev->devclass, dev);
2921 		(void)device_set_driver(dev, NULL);
2922 		device_sysctl_fini(dev);
2923 		KASSERT(dev->busy == 0, ("attach failed but busy"));
2924 		dev->state = DS_NOTPRESENT;
2925 		return (error);
2926 	}
2927 	attachtime = get_cyclecount() - attachtime;
2928 	/*
2929 	 * 4 bits per device is a reasonable value for desktop and server
2930 	 * hardware with good get_cyclecount() implementations, but WILL
2931 	 * need to be adjusted on other platforms.
2932 	 */
2933 #define	RANDOM_PROBE_BIT_GUESS	4
2934 	if (bootverbose)
2935 		printf("random: harvesting attach, %zu bytes (%d bits) from %s%d\n",
2936 		    sizeof(attachtime), RANDOM_PROBE_BIT_GUESS,
2937 		    dev->driver->name, dev->unit);
2938 	random_harvest_direct(&attachtime, sizeof(attachtime),
2939 	    RANDOM_PROBE_BIT_GUESS, RANDOM_ATTACH);
2940 	device_sysctl_update(dev);
2941 	if (dev->busy)
2942 		dev->state = DS_BUSY;
2943 	else
2944 		dev->state = DS_ATTACHED;
2945 	dev->flags &= ~DF_DONENOMATCH;
2946 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
2947 	devadded(dev);
2948 	return (0);
2949 }
2950 
2951 /**
2952  * @brief Detach a driver from a device
2953  *
2954  * This function is a wrapper around the DEVICE_DETACH() driver
2955  * method. If the call to DEVICE_DETACH() succeeds, it calls
2956  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
2957  * notification event for user-based device management services and
2958  * cleans up the device's sysctl tree.
2959  *
2960  * @param dev		the device to un-initialise
2961  *
2962  * @retval 0		success
2963  * @retval ENXIO	no driver was found
2964  * @retval ENOMEM	memory allocation failure
2965  * @retval non-zero	some other unix error code
2966  */
2967 int
2968 device_detach(device_t dev)
2969 {
2970 	int error;
2971 
2972 	GIANT_REQUIRED;
2973 
2974 	PDEBUG(("%s", DEVICENAME(dev)));
2975 	if (dev->state == DS_BUSY)
2976 		return (EBUSY);
2977 	if (dev->state != DS_ATTACHED)
2978 		return (0);
2979 
2980 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
2981 	if ((error = DEVICE_DETACH(dev)) != 0) {
2982 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
2983 		    EVHDEV_DETACH_FAILED);
2984 		return (error);
2985 	} else {
2986 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
2987 		    EVHDEV_DETACH_COMPLETE);
2988 	}
2989 	devremoved(dev);
2990 	if (!device_is_quiet(dev))
2991 		device_printf(dev, "detached\n");
2992 	if (dev->parent)
2993 		BUS_CHILD_DETACHED(dev->parent, dev);
2994 
2995 	if (!(dev->flags & DF_FIXEDCLASS))
2996 		devclass_delete_device(dev->devclass, dev);
2997 
2998 	device_verbose(dev);
2999 	dev->state = DS_NOTPRESENT;
3000 	(void)device_set_driver(dev, NULL);
3001 	device_sysctl_fini(dev);
3002 
3003 	return (0);
3004 }
3005 
3006 /**
3007  * @brief Tells a driver to quiesce itself.
3008  *
3009  * This function is a wrapper around the DEVICE_QUIESCE() driver
3010  * method. If the call to DEVICE_QUIESCE() succeeds.
3011  *
3012  * @param dev		the device to quiesce
3013  *
3014  * @retval 0		success
3015  * @retval ENXIO	no driver was found
3016  * @retval ENOMEM	memory allocation failure
3017  * @retval non-zero	some other unix error code
3018  */
3019 int
3020 device_quiesce(device_t dev)
3021 {
3022 
3023 	PDEBUG(("%s", DEVICENAME(dev)));
3024 	if (dev->state == DS_BUSY)
3025 		return (EBUSY);
3026 	if (dev->state != DS_ATTACHED)
3027 		return (0);
3028 
3029 	return (DEVICE_QUIESCE(dev));
3030 }
3031 
3032 /**
3033  * @brief Notify a device of system shutdown
3034  *
3035  * This function calls the DEVICE_SHUTDOWN() driver method if the
3036  * device currently has an attached driver.
3037  *
3038  * @returns the value returned by DEVICE_SHUTDOWN()
3039  */
3040 int
3041 device_shutdown(device_t dev)
3042 {
3043 	if (dev->state < DS_ATTACHED)
3044 		return (0);
3045 	return (DEVICE_SHUTDOWN(dev));
3046 }
3047 
3048 /**
3049  * @brief Set the unit number of a device
3050  *
3051  * This function can be used to override the unit number used for a
3052  * device (e.g. to wire a device to a pre-configured unit number).
3053  */
3054 int
3055 device_set_unit(device_t dev, int unit)
3056 {
3057 	devclass_t dc;
3058 	int err;
3059 
3060 	dc = device_get_devclass(dev);
3061 	if (unit < dc->maxunit && dc->devices[unit])
3062 		return (EBUSY);
3063 	err = devclass_delete_device(dc, dev);
3064 	if (err)
3065 		return (err);
3066 	dev->unit = unit;
3067 	err = devclass_add_device(dc, dev);
3068 	if (err)
3069 		return (err);
3070 
3071 	bus_data_generation_update();
3072 	return (0);
3073 }
3074 
3075 /*======================================*/
3076 /*
3077  * Some useful method implementations to make life easier for bus drivers.
3078  */
3079 
3080 void
3081 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3082 {
3083 
3084 	bzero(args, sz);
3085 	args->size = sz;
3086 	args->memattr = VM_MEMATTR_UNCACHEABLE;
3087 }
3088 
3089 /**
3090  * @brief Initialise a resource list.
3091  *
3092  * @param rl		the resource list to initialise
3093  */
3094 void
3095 resource_list_init(struct resource_list *rl)
3096 {
3097 	STAILQ_INIT(rl);
3098 }
3099 
3100 /**
3101  * @brief Reclaim memory used by a resource list.
3102  *
3103  * This function frees the memory for all resource entries on the list
3104  * (if any).
3105  *
3106  * @param rl		the resource list to free
3107  */
3108 void
3109 resource_list_free(struct resource_list *rl)
3110 {
3111 	struct resource_list_entry *rle;
3112 
3113 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3114 		if (rle->res)
3115 			panic("resource_list_free: resource entry is busy");
3116 		STAILQ_REMOVE_HEAD(rl, link);
3117 		free(rle, M_BUS);
3118 	}
3119 }
3120 
3121 /**
3122  * @brief Add a resource entry.
3123  *
3124  * This function adds a resource entry using the given @p type, @p
3125  * start, @p end and @p count values. A rid value is chosen by
3126  * searching sequentially for the first unused rid starting at zero.
3127  *
3128  * @param rl		the resource list to edit
3129  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3130  * @param start		the start address of the resource
3131  * @param end		the end address of the resource
3132  * @param count		XXX end-start+1
3133  */
3134 int
3135 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3136     rman_res_t end, rman_res_t count)
3137 {
3138 	int rid;
3139 
3140 	rid = 0;
3141 	while (resource_list_find(rl, type, rid) != NULL)
3142 		rid++;
3143 	resource_list_add(rl, type, rid, start, end, count);
3144 	return (rid);
3145 }
3146 
3147 /**
3148  * @brief Add or modify a resource entry.
3149  *
3150  * If an existing entry exists with the same type and rid, it will be
3151  * modified using the given values of @p start, @p end and @p
3152  * count. If no entry exists, a new one will be created using the
3153  * given values.  The resource list entry that matches is then returned.
3154  *
3155  * @param rl		the resource list to edit
3156  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3157  * @param rid		the resource identifier
3158  * @param start		the start address of the resource
3159  * @param end		the end address of the resource
3160  * @param count		XXX end-start+1
3161  */
3162 struct resource_list_entry *
3163 resource_list_add(struct resource_list *rl, int type, int rid,
3164     rman_res_t start, rman_res_t end, rman_res_t count)
3165 {
3166 	struct resource_list_entry *rle;
3167 
3168 	rle = resource_list_find(rl, type, rid);
3169 	if (!rle) {
3170 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3171 		    M_NOWAIT);
3172 		if (!rle)
3173 			panic("resource_list_add: can't record entry");
3174 		STAILQ_INSERT_TAIL(rl, rle, link);
3175 		rle->type = type;
3176 		rle->rid = rid;
3177 		rle->res = NULL;
3178 		rle->flags = 0;
3179 	}
3180 
3181 	if (rle->res)
3182 		panic("resource_list_add: resource entry is busy");
3183 
3184 	rle->start = start;
3185 	rle->end = end;
3186 	rle->count = count;
3187 	return (rle);
3188 }
3189 
3190 /**
3191  * @brief Determine if a resource entry is busy.
3192  *
3193  * Returns true if a resource entry is busy meaning that it has an
3194  * associated resource that is not an unallocated "reserved" resource.
3195  *
3196  * @param rl		the resource list to search
3197  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3198  * @param rid		the resource identifier
3199  *
3200  * @returns Non-zero if the entry is busy, zero otherwise.
3201  */
3202 int
3203 resource_list_busy(struct resource_list *rl, int type, int rid)
3204 {
3205 	struct resource_list_entry *rle;
3206 
3207 	rle = resource_list_find(rl, type, rid);
3208 	if (rle == NULL || rle->res == NULL)
3209 		return (0);
3210 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3211 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3212 		    ("reserved resource is active"));
3213 		return (0);
3214 	}
3215 	return (1);
3216 }
3217 
3218 /**
3219  * @brief Determine if a resource entry is reserved.
3220  *
3221  * Returns true if a resource entry is reserved meaning that it has an
3222  * associated "reserved" resource.  The resource can either be
3223  * allocated or unallocated.
3224  *
3225  * @param rl		the resource list to search
3226  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3227  * @param rid		the resource identifier
3228  *
3229  * @returns Non-zero if the entry is reserved, zero otherwise.
3230  */
3231 int
3232 resource_list_reserved(struct resource_list *rl, int type, int rid)
3233 {
3234 	struct resource_list_entry *rle;
3235 
3236 	rle = resource_list_find(rl, type, rid);
3237 	if (rle != NULL && rle->flags & RLE_RESERVED)
3238 		return (1);
3239 	return (0);
3240 }
3241 
3242 /**
3243  * @brief Find a resource entry by type and rid.
3244  *
3245  * @param rl		the resource list to search
3246  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3247  * @param rid		the resource identifier
3248  *
3249  * @returns the resource entry pointer or NULL if there is no such
3250  * entry.
3251  */
3252 struct resource_list_entry *
3253 resource_list_find(struct resource_list *rl, int type, int rid)
3254 {
3255 	struct resource_list_entry *rle;
3256 
3257 	STAILQ_FOREACH(rle, rl, link) {
3258 		if (rle->type == type && rle->rid == rid)
3259 			return (rle);
3260 	}
3261 	return (NULL);
3262 }
3263 
3264 /**
3265  * @brief Delete a resource entry.
3266  *
3267  * @param rl		the resource list to edit
3268  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3269  * @param rid		the resource identifier
3270  */
3271 void
3272 resource_list_delete(struct resource_list *rl, int type, int rid)
3273 {
3274 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3275 
3276 	if (rle) {
3277 		if (rle->res != NULL)
3278 			panic("resource_list_delete: resource has not been released");
3279 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3280 		free(rle, M_BUS);
3281 	}
3282 }
3283 
3284 /**
3285  * @brief Allocate a reserved resource
3286  *
3287  * This can be used by buses to force the allocation of resources
3288  * that are always active in the system even if they are not allocated
3289  * by a driver (e.g. PCI BARs).  This function is usually called when
3290  * adding a new child to the bus.  The resource is allocated from the
3291  * parent bus when it is reserved.  The resource list entry is marked
3292  * with RLE_RESERVED to note that it is a reserved resource.
3293  *
3294  * Subsequent attempts to allocate the resource with
3295  * resource_list_alloc() will succeed the first time and will set
3296  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3297  * resource that has been allocated is released with
3298  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3299  * the actual resource remains allocated.  The resource can be released to
3300  * the parent bus by calling resource_list_unreserve().
3301  *
3302  * @param rl		the resource list to allocate from
3303  * @param bus		the parent device of @p child
3304  * @param child		the device for which the resource is being reserved
3305  * @param type		the type of resource to allocate
3306  * @param rid		a pointer to the resource identifier
3307  * @param start		hint at the start of the resource range - pass
3308  *			@c 0 for any start address
3309  * @param end		hint at the end of the resource range - pass
3310  *			@c ~0 for any end address
3311  * @param count		hint at the size of range required - pass @c 1
3312  *			for any size
3313  * @param flags		any extra flags to control the resource
3314  *			allocation - see @c RF_XXX flags in
3315  *			<sys/rman.h> for details
3316  *
3317  * @returns		the resource which was allocated or @c NULL if no
3318  *			resource could be allocated
3319  */
3320 struct resource *
3321 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3322     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3323 {
3324 	struct resource_list_entry *rle = NULL;
3325 	int passthrough = (device_get_parent(child) != bus);
3326 	struct resource *r;
3327 
3328 	if (passthrough)
3329 		panic(
3330     "resource_list_reserve() should only be called for direct children");
3331 	if (flags & RF_ACTIVE)
3332 		panic(
3333     "resource_list_reserve() should only reserve inactive resources");
3334 
3335 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3336 	    flags);
3337 	if (r != NULL) {
3338 		rle = resource_list_find(rl, type, *rid);
3339 		rle->flags |= RLE_RESERVED;
3340 	}
3341 	return (r);
3342 }
3343 
3344 /**
3345  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3346  *
3347  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3348  * and passing the allocation up to the parent of @p bus. This assumes
3349  * that the first entry of @c device_get_ivars(child) is a struct
3350  * resource_list. This also handles 'passthrough' allocations where a
3351  * child is a remote descendant of bus by passing the allocation up to
3352  * the parent of bus.
3353  *
3354  * Typically, a bus driver would store a list of child resources
3355  * somewhere in the child device's ivars (see device_get_ivars()) and
3356  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3357  * then call resource_list_alloc() to perform the allocation.
3358  *
3359  * @param rl		the resource list to allocate from
3360  * @param bus		the parent device of @p child
3361  * @param child		the device which is requesting an allocation
3362  * @param type		the type of resource to allocate
3363  * @param rid		a pointer to the resource identifier
3364  * @param start		hint at the start of the resource range - pass
3365  *			@c 0 for any start address
3366  * @param end		hint at the end of the resource range - pass
3367  *			@c ~0 for any end address
3368  * @param count		hint at the size of range required - pass @c 1
3369  *			for any size
3370  * @param flags		any extra flags to control the resource
3371  *			allocation - see @c RF_XXX flags in
3372  *			<sys/rman.h> for details
3373  *
3374  * @returns		the resource which was allocated or @c NULL if no
3375  *			resource could be allocated
3376  */
3377 struct resource *
3378 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3379     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3380 {
3381 	struct resource_list_entry *rle = NULL;
3382 	int passthrough = (device_get_parent(child) != bus);
3383 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3384 
3385 	if (passthrough) {
3386 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3387 		    type, rid, start, end, count, flags));
3388 	}
3389 
3390 	rle = resource_list_find(rl, type, *rid);
3391 
3392 	if (!rle)
3393 		return (NULL);		/* no resource of that type/rid */
3394 
3395 	if (rle->res) {
3396 		if (rle->flags & RLE_RESERVED) {
3397 			if (rle->flags & RLE_ALLOCATED)
3398 				return (NULL);
3399 			if ((flags & RF_ACTIVE) &&
3400 			    bus_activate_resource(child, type, *rid,
3401 			    rle->res) != 0)
3402 				return (NULL);
3403 			rle->flags |= RLE_ALLOCATED;
3404 			return (rle->res);
3405 		}
3406 		device_printf(bus,
3407 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3408 		    type, device_get_nameunit(child));
3409 		return (NULL);
3410 	}
3411 
3412 	if (isdefault) {
3413 		start = rle->start;
3414 		count = ulmax(count, rle->count);
3415 		end = ulmax(rle->end, start + count - 1);
3416 	}
3417 
3418 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3419 	    type, rid, start, end, count, flags);
3420 
3421 	/*
3422 	 * Record the new range.
3423 	 */
3424 	if (rle->res) {
3425 		rle->start = rman_get_start(rle->res);
3426 		rle->end = rman_get_end(rle->res);
3427 		rle->count = count;
3428 	}
3429 
3430 	return (rle->res);
3431 }
3432 
3433 /**
3434  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3435  *
3436  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3437  * used with resource_list_alloc().
3438  *
3439  * @param rl		the resource list which was allocated from
3440  * @param bus		the parent device of @p child
3441  * @param child		the device which is requesting a release
3442  * @param type		the type of resource to release
3443  * @param rid		the resource identifier
3444  * @param res		the resource to release
3445  *
3446  * @retval 0		success
3447  * @retval non-zero	a standard unix error code indicating what
3448  *			error condition prevented the operation
3449  */
3450 int
3451 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3452     int type, int rid, struct resource *res)
3453 {
3454 	struct resource_list_entry *rle = NULL;
3455 	int passthrough = (device_get_parent(child) != bus);
3456 	int error;
3457 
3458 	if (passthrough) {
3459 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3460 		    type, rid, res));
3461 	}
3462 
3463 	rle = resource_list_find(rl, type, rid);
3464 
3465 	if (!rle)
3466 		panic("resource_list_release: can't find resource");
3467 	if (!rle->res)
3468 		panic("resource_list_release: resource entry is not busy");
3469 	if (rle->flags & RLE_RESERVED) {
3470 		if (rle->flags & RLE_ALLOCATED) {
3471 			if (rman_get_flags(res) & RF_ACTIVE) {
3472 				error = bus_deactivate_resource(child, type,
3473 				    rid, res);
3474 				if (error)
3475 					return (error);
3476 			}
3477 			rle->flags &= ~RLE_ALLOCATED;
3478 			return (0);
3479 		}
3480 		return (EINVAL);
3481 	}
3482 
3483 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3484 	    type, rid, res);
3485 	if (error)
3486 		return (error);
3487 
3488 	rle->res = NULL;
3489 	return (0);
3490 }
3491 
3492 /**
3493  * @brief Release all active resources of a given type
3494  *
3495  * Release all active resources of a specified type.  This is intended
3496  * to be used to cleanup resources leaked by a driver after detach or
3497  * a failed attach.
3498  *
3499  * @param rl		the resource list which was allocated from
3500  * @param bus		the parent device of @p child
3501  * @param child		the device whose active resources are being released
3502  * @param type		the type of resources to release
3503  *
3504  * @retval 0		success
3505  * @retval EBUSY	at least one resource was active
3506  */
3507 int
3508 resource_list_release_active(struct resource_list *rl, device_t bus,
3509     device_t child, int type)
3510 {
3511 	struct resource_list_entry *rle;
3512 	int error, retval;
3513 
3514 	retval = 0;
3515 	STAILQ_FOREACH(rle, rl, link) {
3516 		if (rle->type != type)
3517 			continue;
3518 		if (rle->res == NULL)
3519 			continue;
3520 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3521 		    RLE_RESERVED)
3522 			continue;
3523 		retval = EBUSY;
3524 		error = resource_list_release(rl, bus, child, type,
3525 		    rman_get_rid(rle->res), rle->res);
3526 		if (error != 0)
3527 			device_printf(bus,
3528 			    "Failed to release active resource: %d\n", error);
3529 	}
3530 	return (retval);
3531 }
3532 
3533 
3534 /**
3535  * @brief Fully release a reserved resource
3536  *
3537  * Fully releases a resource reserved via resource_list_reserve().
3538  *
3539  * @param rl		the resource list which was allocated from
3540  * @param bus		the parent device of @p child
3541  * @param child		the device whose reserved resource is being released
3542  * @param type		the type of resource to release
3543  * @param rid		the resource identifier
3544  * @param res		the resource to release
3545  *
3546  * @retval 0		success
3547  * @retval non-zero	a standard unix error code indicating what
3548  *			error condition prevented the operation
3549  */
3550 int
3551 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3552     int type, int rid)
3553 {
3554 	struct resource_list_entry *rle = NULL;
3555 	int passthrough = (device_get_parent(child) != bus);
3556 
3557 	if (passthrough)
3558 		panic(
3559     "resource_list_unreserve() should only be called for direct children");
3560 
3561 	rle = resource_list_find(rl, type, rid);
3562 
3563 	if (!rle)
3564 		panic("resource_list_unreserve: can't find resource");
3565 	if (!(rle->flags & RLE_RESERVED))
3566 		return (EINVAL);
3567 	if (rle->flags & RLE_ALLOCATED)
3568 		return (EBUSY);
3569 	rle->flags &= ~RLE_RESERVED;
3570 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3571 }
3572 
3573 /**
3574  * @brief Print a description of resources in a resource list
3575  *
3576  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3577  * The name is printed if at least one resource of the given type is available.
3578  * The format is used to print resource start and end.
3579  *
3580  * @param rl		the resource list to print
3581  * @param name		the name of @p type, e.g. @c "memory"
3582  * @param type		type type of resource entry to print
3583  * @param format	printf(9) format string to print resource
3584  *			start and end values
3585  *
3586  * @returns		the number of characters printed
3587  */
3588 int
3589 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3590     const char *format)
3591 {
3592 	struct resource_list_entry *rle;
3593 	int printed, retval;
3594 
3595 	printed = 0;
3596 	retval = 0;
3597 	/* Yes, this is kinda cheating */
3598 	STAILQ_FOREACH(rle, rl, link) {
3599 		if (rle->type == type) {
3600 			if (printed == 0)
3601 				retval += printf(" %s ", name);
3602 			else
3603 				retval += printf(",");
3604 			printed++;
3605 			retval += printf(format, rle->start);
3606 			if (rle->count > 1) {
3607 				retval += printf("-");
3608 				retval += printf(format, rle->start +
3609 						 rle->count - 1);
3610 			}
3611 		}
3612 	}
3613 	return (retval);
3614 }
3615 
3616 /**
3617  * @brief Releases all the resources in a list.
3618  *
3619  * @param rl		The resource list to purge.
3620  *
3621  * @returns		nothing
3622  */
3623 void
3624 resource_list_purge(struct resource_list *rl)
3625 {
3626 	struct resource_list_entry *rle;
3627 
3628 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3629 		if (rle->res)
3630 			bus_release_resource(rman_get_device(rle->res),
3631 			    rle->type, rle->rid, rle->res);
3632 		STAILQ_REMOVE_HEAD(rl, link);
3633 		free(rle, M_BUS);
3634 	}
3635 }
3636 
3637 device_t
3638 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3639 {
3640 
3641 	return (device_add_child_ordered(dev, order, name, unit));
3642 }
3643 
3644 /**
3645  * @brief Helper function for implementing DEVICE_PROBE()
3646  *
3647  * This function can be used to help implement the DEVICE_PROBE() for
3648  * a bus (i.e. a device which has other devices attached to it). It
3649  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3650  * devclass.
3651  */
3652 int
3653 bus_generic_probe(device_t dev)
3654 {
3655 	devclass_t dc = dev->devclass;
3656 	driverlink_t dl;
3657 
3658 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3659 		/*
3660 		 * If this driver's pass is too high, then ignore it.
3661 		 * For most drivers in the default pass, this will
3662 		 * never be true.  For early-pass drivers they will
3663 		 * only call the identify routines of eligible drivers
3664 		 * when this routine is called.  Drivers for later
3665 		 * passes should have their identify routines called
3666 		 * on early-pass buses during BUS_NEW_PASS().
3667 		 */
3668 		if (dl->pass > bus_current_pass)
3669 			continue;
3670 		DEVICE_IDENTIFY(dl->driver, dev);
3671 	}
3672 
3673 	return (0);
3674 }
3675 
3676 /**
3677  * @brief Helper function for implementing DEVICE_ATTACH()
3678  *
3679  * This function can be used to help implement the DEVICE_ATTACH() for
3680  * a bus. It calls device_probe_and_attach() for each of the device's
3681  * children.
3682  */
3683 int
3684 bus_generic_attach(device_t dev)
3685 {
3686 	device_t child;
3687 
3688 	TAILQ_FOREACH(child, &dev->children, link) {
3689 		device_probe_and_attach(child);
3690 	}
3691 
3692 	return (0);
3693 }
3694 
3695 /**
3696  * @brief Helper function for implementing DEVICE_DETACH()
3697  *
3698  * This function can be used to help implement the DEVICE_DETACH() for
3699  * a bus. It calls device_detach() for each of the device's
3700  * children.
3701  */
3702 int
3703 bus_generic_detach(device_t dev)
3704 {
3705 	device_t child;
3706 	int error;
3707 
3708 	if (dev->state != DS_ATTACHED)
3709 		return (EBUSY);
3710 
3711 	TAILQ_FOREACH(child, &dev->children, link) {
3712 		if ((error = device_detach(child)) != 0)
3713 			return (error);
3714 	}
3715 
3716 	return (0);
3717 }
3718 
3719 /**
3720  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3721  *
3722  * This function can be used to help implement the DEVICE_SHUTDOWN()
3723  * for a bus. It calls device_shutdown() for each of the device's
3724  * children.
3725  */
3726 int
3727 bus_generic_shutdown(device_t dev)
3728 {
3729 	device_t child;
3730 
3731 	TAILQ_FOREACH(child, &dev->children, link) {
3732 		device_shutdown(child);
3733 	}
3734 
3735 	return (0);
3736 }
3737 
3738 /**
3739  * @brief Default function for suspending a child device.
3740  *
3741  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3742  */
3743 int
3744 bus_generic_suspend_child(device_t dev, device_t child)
3745 {
3746 	int	error;
3747 
3748 	error = DEVICE_SUSPEND(child);
3749 
3750 	if (error == 0)
3751 		child->flags |= DF_SUSPENDED;
3752 
3753 	return (error);
3754 }
3755 
3756 /**
3757  * @brief Default function for resuming a child device.
3758  *
3759  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3760  */
3761 int
3762 bus_generic_resume_child(device_t dev, device_t child)
3763 {
3764 
3765 	DEVICE_RESUME(child);
3766 	child->flags &= ~DF_SUSPENDED;
3767 
3768 	return (0);
3769 }
3770 
3771 /**
3772  * @brief Helper function for implementing DEVICE_SUSPEND()
3773  *
3774  * This function can be used to help implement the DEVICE_SUSPEND()
3775  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3776  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3777  * operation is aborted and any devices which were suspended are
3778  * resumed immediately by calling their DEVICE_RESUME() methods.
3779  */
3780 int
3781 bus_generic_suspend(device_t dev)
3782 {
3783 	int		error;
3784 	device_t	child, child2;
3785 
3786 	TAILQ_FOREACH(child, &dev->children, link) {
3787 		error = BUS_SUSPEND_CHILD(dev, child);
3788 		if (error) {
3789 			for (child2 = TAILQ_FIRST(&dev->children);
3790 			     child2 && child2 != child;
3791 			     child2 = TAILQ_NEXT(child2, link))
3792 				BUS_RESUME_CHILD(dev, child2);
3793 			return (error);
3794 		}
3795 	}
3796 	return (0);
3797 }
3798 
3799 /**
3800  * @brief Helper function for implementing DEVICE_RESUME()
3801  *
3802  * This function can be used to help implement the DEVICE_RESUME() for
3803  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3804  */
3805 int
3806 bus_generic_resume(device_t dev)
3807 {
3808 	device_t	child;
3809 
3810 	TAILQ_FOREACH(child, &dev->children, link) {
3811 		BUS_RESUME_CHILD(dev, child);
3812 		/* if resume fails, there's nothing we can usefully do... */
3813 	}
3814 	return (0);
3815 }
3816 
3817 /**
3818  * @brief Helper function for implementing BUS_PRINT_CHILD().
3819  *
3820  * This function prints the first part of the ascii representation of
3821  * @p child, including its name, unit and description (if any - see
3822  * device_set_desc()).
3823  *
3824  * @returns the number of characters printed
3825  */
3826 int
3827 bus_print_child_header(device_t dev, device_t child)
3828 {
3829 	int	retval = 0;
3830 
3831 	if (device_get_desc(child)) {
3832 		retval += device_printf(child, "<%s>", device_get_desc(child));
3833 	} else {
3834 		retval += printf("%s", device_get_nameunit(child));
3835 	}
3836 
3837 	return (retval);
3838 }
3839 
3840 /**
3841  * @brief Helper function for implementing BUS_PRINT_CHILD().
3842  *
3843  * This function prints the last part of the ascii representation of
3844  * @p child, which consists of the string @c " on " followed by the
3845  * name and unit of the @p dev.
3846  *
3847  * @returns the number of characters printed
3848  */
3849 int
3850 bus_print_child_footer(device_t dev, device_t child)
3851 {
3852 	return (printf(" on %s\n", device_get_nameunit(dev)));
3853 }
3854 
3855 /**
3856  * @brief Helper function for implementing BUS_PRINT_CHILD().
3857  *
3858  * This function prints out the VM domain for the given device.
3859  *
3860  * @returns the number of characters printed
3861  */
3862 int
3863 bus_print_child_domain(device_t dev, device_t child)
3864 {
3865 	int domain;
3866 
3867 	/* No domain? Don't print anything */
3868 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
3869 		return (0);
3870 
3871 	return (printf(" numa-domain %d", domain));
3872 }
3873 
3874 /**
3875  * @brief Helper function for implementing BUS_PRINT_CHILD().
3876  *
3877  * This function simply calls bus_print_child_header() followed by
3878  * bus_print_child_footer().
3879  *
3880  * @returns the number of characters printed
3881  */
3882 int
3883 bus_generic_print_child(device_t dev, device_t child)
3884 {
3885 	int	retval = 0;
3886 
3887 	retval += bus_print_child_header(dev, child);
3888 	retval += bus_print_child_domain(dev, child);
3889 	retval += bus_print_child_footer(dev, child);
3890 
3891 	return (retval);
3892 }
3893 
3894 /**
3895  * @brief Stub function for implementing BUS_READ_IVAR().
3896  *
3897  * @returns ENOENT
3898  */
3899 int
3900 bus_generic_read_ivar(device_t dev, device_t child, int index,
3901     uintptr_t * result)
3902 {
3903 	return (ENOENT);
3904 }
3905 
3906 /**
3907  * @brief Stub function for implementing BUS_WRITE_IVAR().
3908  *
3909  * @returns ENOENT
3910  */
3911 int
3912 bus_generic_write_ivar(device_t dev, device_t child, int index,
3913     uintptr_t value)
3914 {
3915 	return (ENOENT);
3916 }
3917 
3918 /**
3919  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
3920  *
3921  * @returns NULL
3922  */
3923 struct resource_list *
3924 bus_generic_get_resource_list(device_t dev, device_t child)
3925 {
3926 	return (NULL);
3927 }
3928 
3929 /**
3930  * @brief Helper function for implementing BUS_DRIVER_ADDED().
3931  *
3932  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
3933  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
3934  * and then calls device_probe_and_attach() for each unattached child.
3935  */
3936 void
3937 bus_generic_driver_added(device_t dev, driver_t *driver)
3938 {
3939 	device_t child;
3940 
3941 	DEVICE_IDENTIFY(driver, dev);
3942 	TAILQ_FOREACH(child, &dev->children, link) {
3943 		if (child->state == DS_NOTPRESENT ||
3944 		    (child->flags & DF_REBID))
3945 			device_probe_and_attach(child);
3946 	}
3947 }
3948 
3949 /**
3950  * @brief Helper function for implementing BUS_NEW_PASS().
3951  *
3952  * This implementing of BUS_NEW_PASS() first calls the identify
3953  * routines for any drivers that probe at the current pass.  Then it
3954  * walks the list of devices for this bus.  If a device is already
3955  * attached, then it calls BUS_NEW_PASS() on that device.  If the
3956  * device is not already attached, it attempts to attach a driver to
3957  * it.
3958  */
3959 void
3960 bus_generic_new_pass(device_t dev)
3961 {
3962 	driverlink_t dl;
3963 	devclass_t dc;
3964 	device_t child;
3965 
3966 	dc = dev->devclass;
3967 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3968 		if (dl->pass == bus_current_pass)
3969 			DEVICE_IDENTIFY(dl->driver, dev);
3970 	}
3971 	TAILQ_FOREACH(child, &dev->children, link) {
3972 		if (child->state >= DS_ATTACHED)
3973 			BUS_NEW_PASS(child);
3974 		else if (child->state == DS_NOTPRESENT)
3975 			device_probe_and_attach(child);
3976 	}
3977 }
3978 
3979 /**
3980  * @brief Helper function for implementing BUS_SETUP_INTR().
3981  *
3982  * This simple implementation of BUS_SETUP_INTR() simply calls the
3983  * BUS_SETUP_INTR() method of the parent of @p dev.
3984  */
3985 int
3986 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
3987     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
3988     void **cookiep)
3989 {
3990 	/* Propagate up the bus hierarchy until someone handles it. */
3991 	if (dev->parent)
3992 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
3993 		    filter, intr, arg, cookiep));
3994 	return (EINVAL);
3995 }
3996 
3997 /**
3998  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
3999  *
4000  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4001  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4002  */
4003 int
4004 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4005     void *cookie)
4006 {
4007 	/* Propagate up the bus hierarchy until someone handles it. */
4008 	if (dev->parent)
4009 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4010 	return (EINVAL);
4011 }
4012 
4013 /**
4014  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4015  *
4016  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4017  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4018  */
4019 int
4020 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4021     struct resource *r, rman_res_t start, rman_res_t end)
4022 {
4023 	/* Propagate up the bus hierarchy until someone handles it. */
4024 	if (dev->parent)
4025 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4026 		    end));
4027 	return (EINVAL);
4028 }
4029 
4030 /**
4031  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4032  *
4033  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4034  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4035  */
4036 struct resource *
4037 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4038     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4039 {
4040 	/* Propagate up the bus hierarchy until someone handles it. */
4041 	if (dev->parent)
4042 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4043 		    start, end, count, flags));
4044 	return (NULL);
4045 }
4046 
4047 /**
4048  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4049  *
4050  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4051  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4052  */
4053 int
4054 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4055     struct resource *r)
4056 {
4057 	/* Propagate up the bus hierarchy until someone handles it. */
4058 	if (dev->parent)
4059 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4060 		    r));
4061 	return (EINVAL);
4062 }
4063 
4064 /**
4065  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4066  *
4067  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4068  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4069  */
4070 int
4071 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4072     struct resource *r)
4073 {
4074 	/* Propagate up the bus hierarchy until someone handles it. */
4075 	if (dev->parent)
4076 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4077 		    r));
4078 	return (EINVAL);
4079 }
4080 
4081 /**
4082  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4083  *
4084  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4085  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4086  */
4087 int
4088 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4089     int rid, struct resource *r)
4090 {
4091 	/* Propagate up the bus hierarchy until someone handles it. */
4092 	if (dev->parent)
4093 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4094 		    r));
4095 	return (EINVAL);
4096 }
4097 
4098 /**
4099  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4100  *
4101  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4102  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4103  */
4104 int
4105 bus_generic_map_resource(device_t dev, device_t child, int type,
4106     struct resource *r, struct resource_map_request *args,
4107     struct resource_map *map)
4108 {
4109 	/* Propagate up the bus hierarchy until someone handles it. */
4110 	if (dev->parent)
4111 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4112 		    map));
4113 	return (EINVAL);
4114 }
4115 
4116 /**
4117  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4118  *
4119  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4120  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4121  */
4122 int
4123 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4124     struct resource *r, struct resource_map *map)
4125 {
4126 	/* Propagate up the bus hierarchy until someone handles it. */
4127 	if (dev->parent)
4128 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4129 	return (EINVAL);
4130 }
4131 
4132 /**
4133  * @brief Helper function for implementing BUS_BIND_INTR().
4134  *
4135  * This simple implementation of BUS_BIND_INTR() simply calls the
4136  * BUS_BIND_INTR() method of the parent of @p dev.
4137  */
4138 int
4139 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4140     int cpu)
4141 {
4142 
4143 	/* Propagate up the bus hierarchy until someone handles it. */
4144 	if (dev->parent)
4145 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4146 	return (EINVAL);
4147 }
4148 
4149 /**
4150  * @brief Helper function for implementing BUS_CONFIG_INTR().
4151  *
4152  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4153  * BUS_CONFIG_INTR() method of the parent of @p dev.
4154  */
4155 int
4156 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4157     enum intr_polarity pol)
4158 {
4159 
4160 	/* Propagate up the bus hierarchy until someone handles it. */
4161 	if (dev->parent)
4162 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4163 	return (EINVAL);
4164 }
4165 
4166 /**
4167  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4168  *
4169  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4170  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4171  */
4172 int
4173 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4174     void *cookie, const char *descr)
4175 {
4176 
4177 	/* Propagate up the bus hierarchy until someone handles it. */
4178 	if (dev->parent)
4179 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4180 		    descr));
4181 	return (EINVAL);
4182 }
4183 
4184 /**
4185  * @brief Helper function for implementing BUS_GET_CPUS().
4186  *
4187  * This simple implementation of BUS_GET_CPUS() simply calls the
4188  * BUS_GET_CPUS() method of the parent of @p dev.
4189  */
4190 int
4191 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4192     size_t setsize, cpuset_t *cpuset)
4193 {
4194 
4195 	/* Propagate up the bus hierarchy until someone handles it. */
4196 	if (dev->parent != NULL)
4197 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4198 	return (EINVAL);
4199 }
4200 
4201 /**
4202  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4203  *
4204  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4205  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4206  */
4207 bus_dma_tag_t
4208 bus_generic_get_dma_tag(device_t dev, device_t child)
4209 {
4210 
4211 	/* Propagate up the bus hierarchy until someone handles it. */
4212 	if (dev->parent != NULL)
4213 		return (BUS_GET_DMA_TAG(dev->parent, child));
4214 	return (NULL);
4215 }
4216 
4217 /**
4218  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4219  *
4220  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4221  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4222  */
4223 bus_space_tag_t
4224 bus_generic_get_bus_tag(device_t dev, device_t child)
4225 {
4226 
4227 	/* Propagate up the bus hierarchy until someone handles it. */
4228 	if (dev->parent != NULL)
4229 		return (BUS_GET_BUS_TAG(dev->parent, child));
4230 	return ((bus_space_tag_t)0);
4231 }
4232 
4233 /**
4234  * @brief Helper function for implementing BUS_GET_RESOURCE().
4235  *
4236  * This implementation of BUS_GET_RESOURCE() uses the
4237  * resource_list_find() function to do most of the work. It calls
4238  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4239  * search.
4240  */
4241 int
4242 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4243     rman_res_t *startp, rman_res_t *countp)
4244 {
4245 	struct resource_list *		rl = NULL;
4246 	struct resource_list_entry *	rle = NULL;
4247 
4248 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4249 	if (!rl)
4250 		return (EINVAL);
4251 
4252 	rle = resource_list_find(rl, type, rid);
4253 	if (!rle)
4254 		return (ENOENT);
4255 
4256 	if (startp)
4257 		*startp = rle->start;
4258 	if (countp)
4259 		*countp = rle->count;
4260 
4261 	return (0);
4262 }
4263 
4264 /**
4265  * @brief Helper function for implementing BUS_SET_RESOURCE().
4266  *
4267  * This implementation of BUS_SET_RESOURCE() uses the
4268  * resource_list_add() function to do most of the work. It calls
4269  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4270  * edit.
4271  */
4272 int
4273 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4274     rman_res_t start, rman_res_t count)
4275 {
4276 	struct resource_list *		rl = NULL;
4277 
4278 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4279 	if (!rl)
4280 		return (EINVAL);
4281 
4282 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4283 
4284 	return (0);
4285 }
4286 
4287 /**
4288  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4289  *
4290  * This implementation of BUS_DELETE_RESOURCE() uses the
4291  * resource_list_delete() function to do most of the work. It calls
4292  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4293  * edit.
4294  */
4295 void
4296 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4297 {
4298 	struct resource_list *		rl = NULL;
4299 
4300 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4301 	if (!rl)
4302 		return;
4303 
4304 	resource_list_delete(rl, type, rid);
4305 
4306 	return;
4307 }
4308 
4309 /**
4310  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4311  *
4312  * This implementation of BUS_RELEASE_RESOURCE() uses the
4313  * resource_list_release() function to do most of the work. It calls
4314  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4315  */
4316 int
4317 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4318     int rid, struct resource *r)
4319 {
4320 	struct resource_list *		rl = NULL;
4321 
4322 	if (device_get_parent(child) != dev)
4323 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4324 		    type, rid, r));
4325 
4326 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4327 	if (!rl)
4328 		return (EINVAL);
4329 
4330 	return (resource_list_release(rl, dev, child, type, rid, r));
4331 }
4332 
4333 /**
4334  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4335  *
4336  * This implementation of BUS_ALLOC_RESOURCE() uses the
4337  * resource_list_alloc() function to do most of the work. It calls
4338  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4339  */
4340 struct resource *
4341 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4342     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4343 {
4344 	struct resource_list *		rl = NULL;
4345 
4346 	if (device_get_parent(child) != dev)
4347 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4348 		    type, rid, start, end, count, flags));
4349 
4350 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4351 	if (!rl)
4352 		return (NULL);
4353 
4354 	return (resource_list_alloc(rl, dev, child, type, rid,
4355 	    start, end, count, flags));
4356 }
4357 
4358 /**
4359  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4360  *
4361  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4362  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4363  */
4364 int
4365 bus_generic_child_present(device_t dev, device_t child)
4366 {
4367 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4368 }
4369 
4370 int
4371 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4372 {
4373 
4374 	if (dev->parent)
4375 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4376 
4377 	return (ENOENT);
4378 }
4379 
4380 /**
4381  * @brief Helper function for implementing BUS_RESCAN().
4382  *
4383  * This null implementation of BUS_RESCAN() always fails to indicate
4384  * the bus does not support rescanning.
4385  */
4386 int
4387 bus_null_rescan(device_t dev)
4388 {
4389 
4390 	return (ENXIO);
4391 }
4392 
4393 /*
4394  * Some convenience functions to make it easier for drivers to use the
4395  * resource-management functions.  All these really do is hide the
4396  * indirection through the parent's method table, making for slightly
4397  * less-wordy code.  In the future, it might make sense for this code
4398  * to maintain some sort of a list of resources allocated by each device.
4399  */
4400 
4401 int
4402 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4403     struct resource **res)
4404 {
4405 	int i;
4406 
4407 	for (i = 0; rs[i].type != -1; i++)
4408 		res[i] = NULL;
4409 	for (i = 0; rs[i].type != -1; i++) {
4410 		res[i] = bus_alloc_resource_any(dev,
4411 		    rs[i].type, &rs[i].rid, rs[i].flags);
4412 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4413 			bus_release_resources(dev, rs, res);
4414 			return (ENXIO);
4415 		}
4416 	}
4417 	return (0);
4418 }
4419 
4420 void
4421 bus_release_resources(device_t dev, const struct resource_spec *rs,
4422     struct resource **res)
4423 {
4424 	int i;
4425 
4426 	for (i = 0; rs[i].type != -1; i++)
4427 		if (res[i] != NULL) {
4428 			bus_release_resource(
4429 			    dev, rs[i].type, rs[i].rid, res[i]);
4430 			res[i] = NULL;
4431 		}
4432 }
4433 
4434 /**
4435  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4436  *
4437  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4438  * parent of @p dev.
4439  */
4440 struct resource *
4441 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4442     rman_res_t end, rman_res_t count, u_int flags)
4443 {
4444 	struct resource *res;
4445 
4446 	if (dev->parent == NULL)
4447 		return (NULL);
4448 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4449 	    count, flags);
4450 	return (res);
4451 }
4452 
4453 /**
4454  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4455  *
4456  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4457  * parent of @p dev.
4458  */
4459 int
4460 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4461     rman_res_t end)
4462 {
4463 	if (dev->parent == NULL)
4464 		return (EINVAL);
4465 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4466 }
4467 
4468 /**
4469  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4470  *
4471  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4472  * parent of @p dev.
4473  */
4474 int
4475 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4476 {
4477 	if (dev->parent == NULL)
4478 		return (EINVAL);
4479 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4480 }
4481 
4482 /**
4483  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4484  *
4485  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4486  * parent of @p dev.
4487  */
4488 int
4489 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4490 {
4491 	if (dev->parent == NULL)
4492 		return (EINVAL);
4493 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4494 }
4495 
4496 /**
4497  * @brief Wrapper function for BUS_MAP_RESOURCE().
4498  *
4499  * This function simply calls the BUS_MAP_RESOURCE() method of the
4500  * parent of @p dev.
4501  */
4502 int
4503 bus_map_resource(device_t dev, int type, struct resource *r,
4504     struct resource_map_request *args, struct resource_map *map)
4505 {
4506 	if (dev->parent == NULL)
4507 		return (EINVAL);
4508 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4509 }
4510 
4511 /**
4512  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4513  *
4514  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4515  * parent of @p dev.
4516  */
4517 int
4518 bus_unmap_resource(device_t dev, int type, struct resource *r,
4519     struct resource_map *map)
4520 {
4521 	if (dev->parent == NULL)
4522 		return (EINVAL);
4523 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4524 }
4525 
4526 /**
4527  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4528  *
4529  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4530  * parent of @p dev.
4531  */
4532 int
4533 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4534 {
4535 	int rv;
4536 
4537 	if (dev->parent == NULL)
4538 		return (EINVAL);
4539 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4540 	return (rv);
4541 }
4542 
4543 /**
4544  * @brief Wrapper function for BUS_SETUP_INTR().
4545  *
4546  * This function simply calls the BUS_SETUP_INTR() method of the
4547  * parent of @p dev.
4548  */
4549 int
4550 bus_setup_intr(device_t dev, struct resource *r, int flags,
4551     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4552 {
4553 	int error;
4554 
4555 	if (dev->parent == NULL)
4556 		return (EINVAL);
4557 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4558 	    arg, cookiep);
4559 	if (error != 0)
4560 		return (error);
4561 	if (handler != NULL && !(flags & INTR_MPSAFE))
4562 		device_printf(dev, "[GIANT-LOCKED]\n");
4563 	return (0);
4564 }
4565 
4566 /**
4567  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4568  *
4569  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4570  * parent of @p dev.
4571  */
4572 int
4573 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4574 {
4575 	if (dev->parent == NULL)
4576 		return (EINVAL);
4577 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4578 }
4579 
4580 /**
4581  * @brief Wrapper function for BUS_BIND_INTR().
4582  *
4583  * This function simply calls the BUS_BIND_INTR() method of the
4584  * parent of @p dev.
4585  */
4586 int
4587 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4588 {
4589 	if (dev->parent == NULL)
4590 		return (EINVAL);
4591 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4592 }
4593 
4594 /**
4595  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4596  *
4597  * This function first formats the requested description into a
4598  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4599  * the parent of @p dev.
4600  */
4601 int
4602 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4603     const char *fmt, ...)
4604 {
4605 	va_list ap;
4606 	char descr[MAXCOMLEN + 1];
4607 
4608 	if (dev->parent == NULL)
4609 		return (EINVAL);
4610 	va_start(ap, fmt);
4611 	vsnprintf(descr, sizeof(descr), fmt, ap);
4612 	va_end(ap);
4613 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4614 }
4615 
4616 /**
4617  * @brief Wrapper function for BUS_SET_RESOURCE().
4618  *
4619  * This function simply calls the BUS_SET_RESOURCE() method of the
4620  * parent of @p dev.
4621  */
4622 int
4623 bus_set_resource(device_t dev, int type, int rid,
4624     rman_res_t start, rman_res_t count)
4625 {
4626 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4627 	    start, count));
4628 }
4629 
4630 /**
4631  * @brief Wrapper function for BUS_GET_RESOURCE().
4632  *
4633  * This function simply calls the BUS_GET_RESOURCE() method of the
4634  * parent of @p dev.
4635  */
4636 int
4637 bus_get_resource(device_t dev, int type, int rid,
4638     rman_res_t *startp, rman_res_t *countp)
4639 {
4640 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4641 	    startp, countp));
4642 }
4643 
4644 /**
4645  * @brief Wrapper function for BUS_GET_RESOURCE().
4646  *
4647  * This function simply calls the BUS_GET_RESOURCE() method of the
4648  * parent of @p dev and returns the start value.
4649  */
4650 rman_res_t
4651 bus_get_resource_start(device_t dev, int type, int rid)
4652 {
4653 	rman_res_t start;
4654 	rman_res_t count;
4655 	int error;
4656 
4657 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4658 	    &start, &count);
4659 	if (error)
4660 		return (0);
4661 	return (start);
4662 }
4663 
4664 /**
4665  * @brief Wrapper function for BUS_GET_RESOURCE().
4666  *
4667  * This function simply calls the BUS_GET_RESOURCE() method of the
4668  * parent of @p dev and returns the count value.
4669  */
4670 rman_res_t
4671 bus_get_resource_count(device_t dev, int type, int rid)
4672 {
4673 	rman_res_t start;
4674 	rman_res_t count;
4675 	int error;
4676 
4677 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4678 	    &start, &count);
4679 	if (error)
4680 		return (0);
4681 	return (count);
4682 }
4683 
4684 /**
4685  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4686  *
4687  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4688  * parent of @p dev.
4689  */
4690 void
4691 bus_delete_resource(device_t dev, int type, int rid)
4692 {
4693 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4694 }
4695 
4696 /**
4697  * @brief Wrapper function for BUS_CHILD_PRESENT().
4698  *
4699  * This function simply calls the BUS_CHILD_PRESENT() method of the
4700  * parent of @p dev.
4701  */
4702 int
4703 bus_child_present(device_t child)
4704 {
4705 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4706 }
4707 
4708 /**
4709  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4710  *
4711  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4712  * parent of @p dev.
4713  */
4714 int
4715 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4716 {
4717 	device_t parent;
4718 
4719 	parent = device_get_parent(child);
4720 	if (parent == NULL) {
4721 		*buf = '\0';
4722 		return (0);
4723 	}
4724 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4725 }
4726 
4727 /**
4728  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4729  *
4730  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4731  * parent of @p dev.
4732  */
4733 int
4734 bus_child_location_str(device_t child, char *buf, size_t buflen)
4735 {
4736 	device_t parent;
4737 
4738 	parent = device_get_parent(child);
4739 	if (parent == NULL) {
4740 		*buf = '\0';
4741 		return (0);
4742 	}
4743 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4744 }
4745 
4746 /**
4747  * @brief Wrapper function for BUS_GET_CPUS().
4748  *
4749  * This function simply calls the BUS_GET_CPUS() method of the
4750  * parent of @p dev.
4751  */
4752 int
4753 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
4754 {
4755 	device_t parent;
4756 
4757 	parent = device_get_parent(dev);
4758 	if (parent == NULL)
4759 		return (EINVAL);
4760 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
4761 }
4762 
4763 /**
4764  * @brief Wrapper function for BUS_GET_DMA_TAG().
4765  *
4766  * This function simply calls the BUS_GET_DMA_TAG() method of the
4767  * parent of @p dev.
4768  */
4769 bus_dma_tag_t
4770 bus_get_dma_tag(device_t dev)
4771 {
4772 	device_t parent;
4773 
4774 	parent = device_get_parent(dev);
4775 	if (parent == NULL)
4776 		return (NULL);
4777 	return (BUS_GET_DMA_TAG(parent, dev));
4778 }
4779 
4780 /**
4781  * @brief Wrapper function for BUS_GET_BUS_TAG().
4782  *
4783  * This function simply calls the BUS_GET_BUS_TAG() method of the
4784  * parent of @p dev.
4785  */
4786 bus_space_tag_t
4787 bus_get_bus_tag(device_t dev)
4788 {
4789 	device_t parent;
4790 
4791 	parent = device_get_parent(dev);
4792 	if (parent == NULL)
4793 		return ((bus_space_tag_t)0);
4794 	return (BUS_GET_BUS_TAG(parent, dev));
4795 }
4796 
4797 /**
4798  * @brief Wrapper function for BUS_GET_DOMAIN().
4799  *
4800  * This function simply calls the BUS_GET_DOMAIN() method of the
4801  * parent of @p dev.
4802  */
4803 int
4804 bus_get_domain(device_t dev, int *domain)
4805 {
4806 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
4807 }
4808 
4809 /* Resume all devices and then notify userland that we're up again. */
4810 static int
4811 root_resume(device_t dev)
4812 {
4813 	int error;
4814 
4815 	error = bus_generic_resume(dev);
4816 	if (error == 0)
4817 		devctl_notify("kern", "power", "resume", NULL);
4818 	return (error);
4819 }
4820 
4821 static int
4822 root_print_child(device_t dev, device_t child)
4823 {
4824 	int	retval = 0;
4825 
4826 	retval += bus_print_child_header(dev, child);
4827 	retval += printf("\n");
4828 
4829 	return (retval);
4830 }
4831 
4832 static int
4833 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
4834     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
4835 {
4836 	/*
4837 	 * If an interrupt mapping gets to here something bad has happened.
4838 	 */
4839 	panic("root_setup_intr");
4840 }
4841 
4842 /*
4843  * If we get here, assume that the device is permanent and really is
4844  * present in the system.  Removable bus drivers are expected to intercept
4845  * this call long before it gets here.  We return -1 so that drivers that
4846  * really care can check vs -1 or some ERRNO returned higher in the food
4847  * chain.
4848  */
4849 static int
4850 root_child_present(device_t dev, device_t child)
4851 {
4852 	return (-1);
4853 }
4854 
4855 static int
4856 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
4857     cpuset_t *cpuset)
4858 {
4859 
4860 	switch (op) {
4861 	case INTR_CPUS:
4862 		/* Default to returning the set of all CPUs. */
4863 		if (setsize != sizeof(cpuset_t))
4864 			return (EINVAL);
4865 		*cpuset = all_cpus;
4866 		return (0);
4867 	default:
4868 		return (EINVAL);
4869 	}
4870 }
4871 
4872 static kobj_method_t root_methods[] = {
4873 	/* Device interface */
4874 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
4875 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
4876 	KOBJMETHOD(device_resume,	root_resume),
4877 
4878 	/* Bus interface */
4879 	KOBJMETHOD(bus_print_child,	root_print_child),
4880 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
4881 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
4882 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
4883 	KOBJMETHOD(bus_child_present,	root_child_present),
4884 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
4885 
4886 	KOBJMETHOD_END
4887 };
4888 
4889 static driver_t root_driver = {
4890 	"root",
4891 	root_methods,
4892 	1,			/* no softc */
4893 };
4894 
4895 device_t	root_bus;
4896 devclass_t	root_devclass;
4897 
4898 static int
4899 root_bus_module_handler(module_t mod, int what, void* arg)
4900 {
4901 	switch (what) {
4902 	case MOD_LOAD:
4903 		TAILQ_INIT(&bus_data_devices);
4904 		kobj_class_compile((kobj_class_t) &root_driver);
4905 		root_bus = make_device(NULL, "root", 0);
4906 		root_bus->desc = "System root bus";
4907 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
4908 		root_bus->driver = &root_driver;
4909 		root_bus->state = DS_ATTACHED;
4910 		root_devclass = devclass_find_internal("root", NULL, FALSE);
4911 		devinit();
4912 		return (0);
4913 
4914 	case MOD_SHUTDOWN:
4915 		device_shutdown(root_bus);
4916 		return (0);
4917 	default:
4918 		return (EOPNOTSUPP);
4919 	}
4920 
4921 	return (0);
4922 }
4923 
4924 static moduledata_t root_bus_mod = {
4925 	"rootbus",
4926 	root_bus_module_handler,
4927 	NULL
4928 };
4929 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
4930 
4931 /**
4932  * @brief Automatically configure devices
4933  *
4934  * This function begins the autoconfiguration process by calling
4935  * device_probe_and_attach() for each child of the @c root0 device.
4936  */
4937 void
4938 root_bus_configure(void)
4939 {
4940 
4941 	PDEBUG(("."));
4942 
4943 	/* Eventually this will be split up, but this is sufficient for now. */
4944 	bus_set_pass(BUS_PASS_DEFAULT);
4945 }
4946 
4947 /**
4948  * @brief Module handler for registering device drivers
4949  *
4950  * This module handler is used to automatically register device
4951  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
4952  * devclass_add_driver() for the driver described by the
4953  * driver_module_data structure pointed to by @p arg
4954  */
4955 int
4956 driver_module_handler(module_t mod, int what, void *arg)
4957 {
4958 	struct driver_module_data *dmd;
4959 	devclass_t bus_devclass;
4960 	kobj_class_t driver;
4961 	int error, pass;
4962 
4963 	dmd = (struct driver_module_data *)arg;
4964 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
4965 	error = 0;
4966 
4967 	switch (what) {
4968 	case MOD_LOAD:
4969 		if (dmd->dmd_chainevh)
4970 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4971 
4972 		pass = dmd->dmd_pass;
4973 		driver = dmd->dmd_driver;
4974 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
4975 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
4976 		error = devclass_add_driver(bus_devclass, driver, pass,
4977 		    dmd->dmd_devclass);
4978 		break;
4979 
4980 	case MOD_UNLOAD:
4981 		PDEBUG(("Unloading module: driver %s from bus %s",
4982 		    DRIVERNAME(dmd->dmd_driver),
4983 		    dmd->dmd_busname));
4984 		error = devclass_delete_driver(bus_devclass,
4985 		    dmd->dmd_driver);
4986 
4987 		if (!error && dmd->dmd_chainevh)
4988 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4989 		break;
4990 	case MOD_QUIESCE:
4991 		PDEBUG(("Quiesce module: driver %s from bus %s",
4992 		    DRIVERNAME(dmd->dmd_driver),
4993 		    dmd->dmd_busname));
4994 		error = devclass_quiesce_driver(bus_devclass,
4995 		    dmd->dmd_driver);
4996 
4997 		if (!error && dmd->dmd_chainevh)
4998 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
4999 		break;
5000 	default:
5001 		error = EOPNOTSUPP;
5002 		break;
5003 	}
5004 
5005 	return (error);
5006 }
5007 
5008 /**
5009  * @brief Enumerate all hinted devices for this bus.
5010  *
5011  * Walks through the hints for this bus and calls the bus_hinted_child
5012  * routine for each one it fines.  It searches first for the specific
5013  * bus that's being probed for hinted children (eg isa0), and then for
5014  * generic children (eg isa).
5015  *
5016  * @param	dev	bus device to enumerate
5017  */
5018 void
5019 bus_enumerate_hinted_children(device_t bus)
5020 {
5021 	int i;
5022 	const char *dname, *busname;
5023 	int dunit;
5024 
5025 	/*
5026 	 * enumerate all devices on the specific bus
5027 	 */
5028 	busname = device_get_nameunit(bus);
5029 	i = 0;
5030 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5031 		BUS_HINTED_CHILD(bus, dname, dunit);
5032 
5033 	/*
5034 	 * and all the generic ones.
5035 	 */
5036 	busname = device_get_name(bus);
5037 	i = 0;
5038 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5039 		BUS_HINTED_CHILD(bus, dname, dunit);
5040 }
5041 
5042 #ifdef BUS_DEBUG
5043 
5044 /* the _short versions avoid iteration by not calling anything that prints
5045  * more than oneliners. I love oneliners.
5046  */
5047 
5048 static void
5049 print_device_short(device_t dev, int indent)
5050 {
5051 	if (!dev)
5052 		return;
5053 
5054 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5055 	    dev->unit, dev->desc,
5056 	    (dev->parent? "":"no "),
5057 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5058 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5059 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5060 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5061 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5062 	    (dev->flags&DF_REBID? "rebiddable,":""),
5063 	    (dev->ivars? "":"no "),
5064 	    (dev->softc? "":"no "),
5065 	    dev->busy));
5066 }
5067 
5068 static void
5069 print_device(device_t dev, int indent)
5070 {
5071 	if (!dev)
5072 		return;
5073 
5074 	print_device_short(dev, indent);
5075 
5076 	indentprintf(("Parent:\n"));
5077 	print_device_short(dev->parent, indent+1);
5078 	indentprintf(("Driver:\n"));
5079 	print_driver_short(dev->driver, indent+1);
5080 	indentprintf(("Devclass:\n"));
5081 	print_devclass_short(dev->devclass, indent+1);
5082 }
5083 
5084 void
5085 print_device_tree_short(device_t dev, int indent)
5086 /* print the device and all its children (indented) */
5087 {
5088 	device_t child;
5089 
5090 	if (!dev)
5091 		return;
5092 
5093 	print_device_short(dev, indent);
5094 
5095 	TAILQ_FOREACH(child, &dev->children, link) {
5096 		print_device_tree_short(child, indent+1);
5097 	}
5098 }
5099 
5100 void
5101 print_device_tree(device_t dev, int indent)
5102 /* print the device and all its children (indented) */
5103 {
5104 	device_t child;
5105 
5106 	if (!dev)
5107 		return;
5108 
5109 	print_device(dev, indent);
5110 
5111 	TAILQ_FOREACH(child, &dev->children, link) {
5112 		print_device_tree(child, indent+1);
5113 	}
5114 }
5115 
5116 static void
5117 print_driver_short(driver_t *driver, int indent)
5118 {
5119 	if (!driver)
5120 		return;
5121 
5122 	indentprintf(("driver %s: softc size = %zd\n",
5123 	    driver->name, driver->size));
5124 }
5125 
5126 static void
5127 print_driver(driver_t *driver, int indent)
5128 {
5129 	if (!driver)
5130 		return;
5131 
5132 	print_driver_short(driver, indent);
5133 }
5134 
5135 static void
5136 print_driver_list(driver_list_t drivers, int indent)
5137 {
5138 	driverlink_t driver;
5139 
5140 	TAILQ_FOREACH(driver, &drivers, link) {
5141 		print_driver(driver->driver, indent);
5142 	}
5143 }
5144 
5145 static void
5146 print_devclass_short(devclass_t dc, int indent)
5147 {
5148 	if ( !dc )
5149 		return;
5150 
5151 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5152 }
5153 
5154 static void
5155 print_devclass(devclass_t dc, int indent)
5156 {
5157 	int i;
5158 
5159 	if ( !dc )
5160 		return;
5161 
5162 	print_devclass_short(dc, indent);
5163 	indentprintf(("Drivers:\n"));
5164 	print_driver_list(dc->drivers, indent+1);
5165 
5166 	indentprintf(("Devices:\n"));
5167 	for (i = 0; i < dc->maxunit; i++)
5168 		if (dc->devices[i])
5169 			print_device(dc->devices[i], indent+1);
5170 }
5171 
5172 void
5173 print_devclass_list_short(void)
5174 {
5175 	devclass_t dc;
5176 
5177 	printf("Short listing of devclasses, drivers & devices:\n");
5178 	TAILQ_FOREACH(dc, &devclasses, link) {
5179 		print_devclass_short(dc, 0);
5180 	}
5181 }
5182 
5183 void
5184 print_devclass_list(void)
5185 {
5186 	devclass_t dc;
5187 
5188 	printf("Full listing of devclasses, drivers & devices:\n");
5189 	TAILQ_FOREACH(dc, &devclasses, link) {
5190 		print_devclass(dc, 0);
5191 	}
5192 }
5193 
5194 #endif
5195 
5196 /*
5197  * User-space access to the device tree.
5198  *
5199  * We implement a small set of nodes:
5200  *
5201  * hw.bus			Single integer read method to obtain the
5202  *				current generation count.
5203  * hw.bus.devices		Reads the entire device tree in flat space.
5204  * hw.bus.rman			Resource manager interface
5205  *
5206  * We might like to add the ability to scan devclasses and/or drivers to
5207  * determine what else is currently loaded/available.
5208  */
5209 
5210 static int
5211 sysctl_bus(SYSCTL_HANDLER_ARGS)
5212 {
5213 	struct u_businfo	ubus;
5214 
5215 	ubus.ub_version = BUS_USER_VERSION;
5216 	ubus.ub_generation = bus_data_generation;
5217 
5218 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5219 }
5220 SYSCTL_NODE(_hw_bus, OID_AUTO, info, CTLFLAG_RW, sysctl_bus,
5221     "bus-related data");
5222 
5223 static int
5224 sysctl_devices(SYSCTL_HANDLER_ARGS)
5225 {
5226 	int			*name = (int *)arg1;
5227 	u_int			namelen = arg2;
5228 	int			index;
5229 	device_t		dev;
5230 	struct u_device		udev;	/* XXX this is a bit big */
5231 	int			error;
5232 
5233 	if (namelen != 2)
5234 		return (EINVAL);
5235 
5236 	if (bus_data_generation_check(name[0]))
5237 		return (EINVAL);
5238 
5239 	index = name[1];
5240 
5241 	/*
5242 	 * Scan the list of devices, looking for the requested index.
5243 	 */
5244 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5245 		if (index-- == 0)
5246 			break;
5247 	}
5248 	if (dev == NULL)
5249 		return (ENOENT);
5250 
5251 	/*
5252 	 * Populate the return array.
5253 	 */
5254 	bzero(&udev, sizeof(udev));
5255 	udev.dv_handle = (uintptr_t)dev;
5256 	udev.dv_parent = (uintptr_t)dev->parent;
5257 	if (dev->nameunit != NULL)
5258 		strlcpy(udev.dv_name, dev->nameunit, sizeof(udev.dv_name));
5259 	if (dev->desc != NULL)
5260 		strlcpy(udev.dv_desc, dev->desc, sizeof(udev.dv_desc));
5261 	if (dev->driver != NULL && dev->driver->name != NULL)
5262 		strlcpy(udev.dv_drivername, dev->driver->name,
5263 		    sizeof(udev.dv_drivername));
5264 	bus_child_pnpinfo_str(dev, udev.dv_pnpinfo, sizeof(udev.dv_pnpinfo));
5265 	bus_child_location_str(dev, udev.dv_location, sizeof(udev.dv_location));
5266 	udev.dv_devflags = dev->devflags;
5267 	udev.dv_flags = dev->flags;
5268 	udev.dv_state = dev->state;
5269 	error = SYSCTL_OUT(req, &udev, sizeof(udev));
5270 	return (error);
5271 }
5272 
5273 SYSCTL_NODE(_hw_bus, OID_AUTO, devices, CTLFLAG_RD, sysctl_devices,
5274     "system device tree");
5275 
5276 int
5277 bus_data_generation_check(int generation)
5278 {
5279 	if (generation != bus_data_generation)
5280 		return (1);
5281 
5282 	/* XXX generate optimised lists here? */
5283 	return (0);
5284 }
5285 
5286 void
5287 bus_data_generation_update(void)
5288 {
5289 	bus_data_generation++;
5290 }
5291 
5292 int
5293 bus_free_resource(device_t dev, int type, struct resource *r)
5294 {
5295 	if (r == NULL)
5296 		return (0);
5297 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5298 }
5299 
5300 device_t
5301 device_lookup_by_name(const char *name)
5302 {
5303 	device_t dev;
5304 
5305 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5306 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5307 			return (dev);
5308 	}
5309 	return (NULL);
5310 }
5311 
5312 /*
5313  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5314  * implicit semantics on open, so it could not be reused for this.
5315  * Another option would be to call this /dev/bus?
5316  */
5317 static int
5318 find_device(struct devreq *req, device_t *devp)
5319 {
5320 	device_t dev;
5321 
5322 	/*
5323 	 * First, ensure that the name is nul terminated.
5324 	 */
5325 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5326 		return (EINVAL);
5327 
5328 	/*
5329 	 * Second, try to find an attached device whose name matches
5330 	 * 'name'.
5331 	 */
5332 	dev = device_lookup_by_name(req->dr_name);
5333 	if (dev != NULL) {
5334 		*devp = dev;
5335 		return (0);
5336 	}
5337 
5338 	/* Finally, give device enumerators a chance. */
5339 	dev = NULL;
5340 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5341 	if (dev == NULL)
5342 		return (ENOENT);
5343 	*devp = dev;
5344 	return (0);
5345 }
5346 
5347 static bool
5348 driver_exists(device_t bus, const char *driver)
5349 {
5350 	devclass_t dc;
5351 
5352 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5353 		if (devclass_find_driver_internal(dc, driver) != NULL)
5354 			return (true);
5355 	}
5356 	return (false);
5357 }
5358 
5359 static int
5360 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5361     struct thread *td)
5362 {
5363 	struct devreq *req;
5364 	device_t dev;
5365 	int error, old;
5366 
5367 	/* Locate the device to control. */
5368 	mtx_lock(&Giant);
5369 	req = (struct devreq *)data;
5370 	switch (cmd) {
5371 	case DEV_ATTACH:
5372 	case DEV_DETACH:
5373 	case DEV_ENABLE:
5374 	case DEV_DISABLE:
5375 	case DEV_SUSPEND:
5376 	case DEV_RESUME:
5377 	case DEV_SET_DRIVER:
5378 	case DEV_CLEAR_DRIVER:
5379 	case DEV_RESCAN:
5380 	case DEV_DELETE:
5381 		error = priv_check(td, PRIV_DRIVER);
5382 		if (error == 0)
5383 			error = find_device(req, &dev);
5384 		break;
5385 	default:
5386 		error = ENOTTY;
5387 		break;
5388 	}
5389 	if (error) {
5390 		mtx_unlock(&Giant);
5391 		return (error);
5392 	}
5393 
5394 	/* Perform the requested operation. */
5395 	switch (cmd) {
5396 	case DEV_ATTACH:
5397 		if (device_is_attached(dev) && (dev->flags & DF_REBID) == 0)
5398 			error = EBUSY;
5399 		else if (!device_is_enabled(dev))
5400 			error = ENXIO;
5401 		else
5402 			error = device_probe_and_attach(dev);
5403 		break;
5404 	case DEV_DETACH:
5405 		if (!device_is_attached(dev)) {
5406 			error = ENXIO;
5407 			break;
5408 		}
5409 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5410 			error = device_quiesce(dev);
5411 			if (error)
5412 				break;
5413 		}
5414 		error = device_detach(dev);
5415 		break;
5416 	case DEV_ENABLE:
5417 		if (device_is_enabled(dev)) {
5418 			error = EBUSY;
5419 			break;
5420 		}
5421 
5422 		/*
5423 		 * If the device has been probed but not attached (e.g.
5424 		 * when it has been disabled by a loader hint), just
5425 		 * attach the device rather than doing a full probe.
5426 		 */
5427 		device_enable(dev);
5428 		if (device_is_alive(dev)) {
5429 			/*
5430 			 * If the device was disabled via a hint, clear
5431 			 * the hint.
5432 			 */
5433 			if (resource_disabled(dev->driver->name, dev->unit))
5434 				resource_unset_value(dev->driver->name,
5435 				    dev->unit, "disabled");
5436 			error = device_attach(dev);
5437 		} else
5438 			error = device_probe_and_attach(dev);
5439 		break;
5440 	case DEV_DISABLE:
5441 		if (!device_is_enabled(dev)) {
5442 			error = ENXIO;
5443 			break;
5444 		}
5445 
5446 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5447 			error = device_quiesce(dev);
5448 			if (error)
5449 				break;
5450 		}
5451 
5452 		/*
5453 		 * Force DF_FIXEDCLASS on around detach to preserve
5454 		 * the existing name.
5455 		 */
5456 		old = dev->flags;
5457 		dev->flags |= DF_FIXEDCLASS;
5458 		error = device_detach(dev);
5459 		if (!(old & DF_FIXEDCLASS))
5460 			dev->flags &= ~DF_FIXEDCLASS;
5461 		if (error == 0)
5462 			device_disable(dev);
5463 		break;
5464 	case DEV_SUSPEND:
5465 		if (device_is_suspended(dev)) {
5466 			error = EBUSY;
5467 			break;
5468 		}
5469 		if (device_get_parent(dev) == NULL) {
5470 			error = EINVAL;
5471 			break;
5472 		}
5473 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5474 		break;
5475 	case DEV_RESUME:
5476 		if (!device_is_suspended(dev)) {
5477 			error = EINVAL;
5478 			break;
5479 		}
5480 		if (device_get_parent(dev) == NULL) {
5481 			error = EINVAL;
5482 			break;
5483 		}
5484 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5485 		break;
5486 	case DEV_SET_DRIVER: {
5487 		devclass_t dc;
5488 		char driver[128];
5489 
5490 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5491 		if (error)
5492 			break;
5493 		if (driver[0] == '\0') {
5494 			error = EINVAL;
5495 			break;
5496 		}
5497 		if (dev->devclass != NULL &&
5498 		    strcmp(driver, dev->devclass->name) == 0)
5499 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5500 			break;
5501 
5502 		/*
5503 		 * Scan drivers for this device's bus looking for at
5504 		 * least one matching driver.
5505 		 */
5506 		if (dev->parent == NULL) {
5507 			error = EINVAL;
5508 			break;
5509 		}
5510 		if (!driver_exists(dev->parent, driver)) {
5511 			error = ENOENT;
5512 			break;
5513 		}
5514 		dc = devclass_create(driver);
5515 		if (dc == NULL) {
5516 			error = ENOMEM;
5517 			break;
5518 		}
5519 
5520 		/* Detach device if necessary. */
5521 		if (device_is_attached(dev)) {
5522 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5523 				error = device_detach(dev);
5524 			else
5525 				error = EBUSY;
5526 			if (error)
5527 				break;
5528 		}
5529 
5530 		/* Clear any previously-fixed device class and unit. */
5531 		if (dev->flags & DF_FIXEDCLASS)
5532 			devclass_delete_device(dev->devclass, dev);
5533 		dev->flags |= DF_WILDCARD;
5534 		dev->unit = -1;
5535 
5536 		/* Force the new device class. */
5537 		error = devclass_add_device(dc, dev);
5538 		if (error)
5539 			break;
5540 		dev->flags |= DF_FIXEDCLASS;
5541 		error = device_probe_and_attach(dev);
5542 		break;
5543 	}
5544 	case DEV_CLEAR_DRIVER:
5545 		if (!(dev->flags & DF_FIXEDCLASS)) {
5546 			error = 0;
5547 			break;
5548 		}
5549 		if (device_is_attached(dev)) {
5550 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5551 				error = device_detach(dev);
5552 			else
5553 				error = EBUSY;
5554 			if (error)
5555 				break;
5556 		}
5557 
5558 		dev->flags &= ~DF_FIXEDCLASS;
5559 		dev->flags |= DF_WILDCARD;
5560 		devclass_delete_device(dev->devclass, dev);
5561 		error = device_probe_and_attach(dev);
5562 		break;
5563 	case DEV_RESCAN:
5564 		if (!device_is_attached(dev)) {
5565 			error = ENXIO;
5566 			break;
5567 		}
5568 		error = BUS_RESCAN(dev);
5569 		break;
5570 	case DEV_DELETE: {
5571 		device_t parent;
5572 
5573 		parent = device_get_parent(dev);
5574 		if (parent == NULL) {
5575 			error = EINVAL;
5576 			break;
5577 		}
5578 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5579 			if (bus_child_present(dev) != 0) {
5580 				error = EBUSY;
5581 				break;
5582 			}
5583 		}
5584 
5585 		error = device_delete_child(parent, dev);
5586 		break;
5587 	}
5588 	}
5589 	mtx_unlock(&Giant);
5590 	return (error);
5591 }
5592 
5593 static struct cdevsw devctl2_cdevsw = {
5594 	.d_version =	D_VERSION,
5595 	.d_ioctl =	devctl2_ioctl,
5596 	.d_name =	"devctl2",
5597 };
5598 
5599 static void
5600 devctl2_init(void)
5601 {
5602 
5603 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5604 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5605 }
5606 
5607 #ifdef DDB
5608 DB_SHOW_COMMAND(device, db_show_device)
5609 {
5610 	device_t dev;
5611 
5612 	if (!have_addr)
5613 		return;
5614 
5615 	dev = (device_t)addr;
5616 
5617 	db_printf("name:    %s\n", device_get_nameunit(dev));
5618 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
5619 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
5620 	db_printf("  addr:    %p\n", dev);
5621 	db_printf("  parent:  %p\n", dev->parent);
5622 	db_printf("  softc:   %p\n", dev->softc);
5623 	db_printf("  ivars:   %p\n", dev->ivars);
5624 }
5625 
5626 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
5627 {
5628 	device_t dev;
5629 
5630 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5631 		db_show_device((db_expr_t)dev, true, count, modif);
5632 	}
5633 }
5634 #endif
5635