xref: /freebsd/sys/kern/subr_bus.c (revision 833a452e9f082a7982a31c21f0da437dbbe0a39d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/refcount.h>
55 #include <sys/rman.h>
56 #include <sys/sbuf.h>
57 #include <sys/selinfo.h>
58 #include <sys/signalvar.h>
59 #include <sys/smp.h>
60 #include <sys/sysctl.h>
61 #include <sys/systm.h>
62 #include <sys/uio.h>
63 #include <sys/bus.h>
64 #include <sys/cpuset.h>
65 
66 #include <net/vnet.h>
67 
68 #include <machine/cpu.h>
69 #include <machine/stdarg.h>
70 
71 #include <vm/uma.h>
72 #include <vm/vm.h>
73 
74 #include <ddb/ddb.h>
75 
76 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
77     NULL);
78 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
79     NULL);
80 
81 /*
82  * Used to attach drivers to devclasses.
83  */
84 typedef struct driverlink *driverlink_t;
85 struct driverlink {
86 	kobj_class_t	driver;
87 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
88 	int		pass;
89 	int		flags;
90 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
91 	TAILQ_ENTRY(driverlink) passlink;
92 };
93 
94 /*
95  * Forward declarations
96  */
97 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
98 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
99 typedef TAILQ_HEAD(device_list, _device) device_list_t;
100 
101 struct devclass {
102 	TAILQ_ENTRY(devclass) link;
103 	devclass_t	parent;		/* parent in devclass hierarchy */
104 	driver_list_t	drivers;	/* bus devclasses store drivers for bus */
105 	char		*name;
106 	device_t	*devices;	/* array of devices indexed by unit */
107 	int		maxunit;	/* size of devices array */
108 	int		flags;
109 #define DC_HAS_CHILDREN		1
110 
111 	struct sysctl_ctx_list sysctl_ctx;
112 	struct sysctl_oid *sysctl_tree;
113 };
114 
115 /**
116  * @brief Implementation of _device.
117  *
118  * The structure is named "_device" instead of "device" to avoid type confusion
119  * caused by other subsystems defining a (struct device).
120  */
121 struct _device {
122 	/*
123 	 * A device is a kernel object. The first field must be the
124 	 * current ops table for the object.
125 	 */
126 	KOBJ_FIELDS;
127 
128 	/*
129 	 * Device hierarchy.
130 	 */
131 	TAILQ_ENTRY(_device)	link;	/**< list of devices in parent */
132 	TAILQ_ENTRY(_device)	devlink; /**< global device list membership */
133 	device_t	parent;		/**< parent of this device  */
134 	device_list_t	children;	/**< list of child devices */
135 
136 	/*
137 	 * Details of this device.
138 	 */
139 	driver_t	*driver;	/**< current driver */
140 	devclass_t	devclass;	/**< current device class */
141 	int		unit;		/**< current unit number */
142 	char*		nameunit;	/**< name+unit e.g. foodev0 */
143 	char*		desc;		/**< driver specific description */
144 	u_int		busy;		/**< count of calls to device_busy() */
145 	device_state_t	state;		/**< current device state  */
146 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
147 	u_int		flags;		/**< internal device flags  */
148 	u_int	order;			/**< order from device_add_child_ordered() */
149 	void	*ivars;			/**< instance variables  */
150 	void	*softc;			/**< current driver's variables  */
151 
152 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
153 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
154 };
155 
156 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
157 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
158 
159 EVENTHANDLER_LIST_DEFINE(device_attach);
160 EVENTHANDLER_LIST_DEFINE(device_detach);
161 EVENTHANDLER_LIST_DEFINE(dev_lookup);
162 
163 static void devctl2_init(void);
164 static bool device_frozen;
165 
166 #define DRIVERNAME(d)	((d)? d->name : "no driver")
167 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
168 
169 #ifdef BUS_DEBUG
170 
171 static int bus_debug = 1;
172 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
173     "Bus debug level");
174 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
175 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
176 
177 /**
178  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
179  * prevent syslog from deleting initial spaces
180  */
181 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
182 
183 static void print_device_short(device_t dev, int indent);
184 static void print_device(device_t dev, int indent);
185 void print_device_tree_short(device_t dev, int indent);
186 void print_device_tree(device_t dev, int indent);
187 static void print_driver_short(driver_t *driver, int indent);
188 static void print_driver(driver_t *driver, int indent);
189 static void print_driver_list(driver_list_t drivers, int indent);
190 static void print_devclass_short(devclass_t dc, int indent);
191 static void print_devclass(devclass_t dc, int indent);
192 void print_devclass_list_short(void);
193 void print_devclass_list(void);
194 
195 #else
196 /* Make the compiler ignore the function calls */
197 #define PDEBUG(a)			/* nop */
198 #define DEVICENAME(d)			/* nop */
199 
200 #define print_device_short(d,i)		/* nop */
201 #define print_device(d,i)		/* nop */
202 #define print_device_tree_short(d,i)	/* nop */
203 #define print_device_tree(d,i)		/* nop */
204 #define print_driver_short(d,i)		/* nop */
205 #define print_driver(d,i)		/* nop */
206 #define print_driver_list(d,i)		/* nop */
207 #define print_devclass_short(d,i)	/* nop */
208 #define print_devclass(d,i)		/* nop */
209 #define print_devclass_list_short()	/* nop */
210 #define print_devclass_list()		/* nop */
211 #endif
212 
213 /*
214  * dev sysctl tree
215  */
216 
217 enum {
218 	DEVCLASS_SYSCTL_PARENT,
219 };
220 
221 static int
222 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
223 {
224 	devclass_t dc = (devclass_t)arg1;
225 	const char *value;
226 
227 	switch (arg2) {
228 	case DEVCLASS_SYSCTL_PARENT:
229 		value = dc->parent ? dc->parent->name : "";
230 		break;
231 	default:
232 		return (EINVAL);
233 	}
234 	return (SYSCTL_OUT_STR(req, value));
235 }
236 
237 static void
238 devclass_sysctl_init(devclass_t dc)
239 {
240 	if (dc->sysctl_tree != NULL)
241 		return;
242 	sysctl_ctx_init(&dc->sysctl_ctx);
243 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
244 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
245 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
246 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
247 	    OID_AUTO, "%parent",
248 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
249 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
250 	    "parent class");
251 }
252 
253 enum {
254 	DEVICE_SYSCTL_DESC,
255 	DEVICE_SYSCTL_DRIVER,
256 	DEVICE_SYSCTL_LOCATION,
257 	DEVICE_SYSCTL_PNPINFO,
258 	DEVICE_SYSCTL_PARENT,
259 };
260 
261 static int
262 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
263 {
264 	struct sbuf sb;
265 	device_t dev = (device_t)arg1;
266 	int error;
267 
268 	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
269 	sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
270 	bus_topo_lock();
271 	switch (arg2) {
272 	case DEVICE_SYSCTL_DESC:
273 		sbuf_cat(&sb, dev->desc ? dev->desc : "");
274 		break;
275 	case DEVICE_SYSCTL_DRIVER:
276 		sbuf_cat(&sb, dev->driver ? dev->driver->name : "");
277 		break;
278 	case DEVICE_SYSCTL_LOCATION:
279 		bus_child_location(dev, &sb);
280 		break;
281 	case DEVICE_SYSCTL_PNPINFO:
282 		bus_child_pnpinfo(dev, &sb);
283 		break;
284 	case DEVICE_SYSCTL_PARENT:
285 		sbuf_cat(&sb, dev->parent ? dev->parent->nameunit : "");
286 		break;
287 	default:
288 		error = EINVAL;
289 		goto out;
290 	}
291 	error = sbuf_finish(&sb);
292 out:
293 	bus_topo_unlock();
294 	sbuf_delete(&sb);
295 	return (error);
296 }
297 
298 static void
299 device_sysctl_init(device_t dev)
300 {
301 	devclass_t dc = dev->devclass;
302 	int domain;
303 
304 	if (dev->sysctl_tree != NULL)
305 		return;
306 	devclass_sysctl_init(dc);
307 	sysctl_ctx_init(&dev->sysctl_ctx);
308 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
309 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
310 	    dev->nameunit + strlen(dc->name),
311 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
312 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
313 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
314 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
315 	    "device description");
316 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
317 	    OID_AUTO, "%driver",
318 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
319 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
320 	    "device driver name");
321 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
322 	    OID_AUTO, "%location",
323 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
324 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
325 	    "device location relative to parent");
326 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
327 	    OID_AUTO, "%pnpinfo",
328 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
329 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
330 	    "device identification");
331 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
332 	    OID_AUTO, "%parent",
333 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
334 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
335 	    "parent device");
336 	if (bus_get_domain(dev, &domain) == 0)
337 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
338 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
339 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, domain, "NUMA domain");
340 }
341 
342 static void
343 device_sysctl_update(device_t dev)
344 {
345 	devclass_t dc = dev->devclass;
346 
347 	if (dev->sysctl_tree == NULL)
348 		return;
349 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
350 }
351 
352 static void
353 device_sysctl_fini(device_t dev)
354 {
355 	if (dev->sysctl_tree == NULL)
356 		return;
357 	sysctl_ctx_free(&dev->sysctl_ctx);
358 	dev->sysctl_tree = NULL;
359 }
360 
361 /*
362  * /dev/devctl implementation
363  */
364 
365 /*
366  * This design allows only one reader for /dev/devctl.  This is not desirable
367  * in the long run, but will get a lot of hair out of this implementation.
368  * Maybe we should make this device a clonable device.
369  *
370  * Also note: we specifically do not attach a device to the device_t tree
371  * to avoid potential chicken and egg problems.  One could argue that all
372  * of this belongs to the root node.
373  */
374 
375 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
376 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
377 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
378 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
379     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
380 
381 static d_open_t		devopen;
382 static d_close_t	devclose;
383 static d_read_t		devread;
384 static d_ioctl_t	devioctl;
385 static d_poll_t		devpoll;
386 static d_kqfilter_t	devkqfilter;
387 
388 static struct cdevsw dev_cdevsw = {
389 	.d_version =	D_VERSION,
390 	.d_open =	devopen,
391 	.d_close =	devclose,
392 	.d_read =	devread,
393 	.d_ioctl =	devioctl,
394 	.d_poll =	devpoll,
395 	.d_kqfilter =	devkqfilter,
396 	.d_name =	"devctl",
397 };
398 
399 #define DEVCTL_BUFFER (1024 - sizeof(void *))
400 struct dev_event_info {
401 	STAILQ_ENTRY(dev_event_info) dei_link;
402 	char dei_data[DEVCTL_BUFFER];
403 };
404 
405 STAILQ_HEAD(devq, dev_event_info);
406 
407 static struct dev_softc {
408 	int		inuse;
409 	int		nonblock;
410 	int		queued;
411 	int		async;
412 	struct mtx	mtx;
413 	struct cv	cv;
414 	struct selinfo	sel;
415 	struct devq	devq;
416 	struct sigio	*sigio;
417 	uma_zone_t	zone;
418 } devsoftc;
419 
420 static void	filt_devctl_detach(struct knote *kn);
421 static int	filt_devctl_read(struct knote *kn, long hint);
422 
423 struct filterops devctl_rfiltops = {
424 	.f_isfd = 1,
425 	.f_detach = filt_devctl_detach,
426 	.f_event = filt_devctl_read,
427 };
428 
429 static struct cdev *devctl_dev;
430 
431 static void
432 devinit(void)
433 {
434 	int reserve;
435 	uma_zone_t z;
436 
437 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
438 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
439 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
440 	cv_init(&devsoftc.cv, "dev cv");
441 	STAILQ_INIT(&devsoftc.devq);
442 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
443 	if (devctl_queue_length > 0) {
444 		/*
445 		 * Allocate a zone for the messages. Preallocate 2% of these for
446 		 * a reserve. Allow only devctl_queue_length slabs to cap memory
447 		 * usage.  The reserve usually allows coverage of surges of
448 		 * events during memory shortages. Normally we won't have to
449 		 * re-use events from the queue, but will in extreme shortages.
450 		 */
451 		z = devsoftc.zone = uma_zcreate("DEVCTL",
452 		    sizeof(struct dev_event_info), NULL, NULL, NULL, NULL,
453 		    UMA_ALIGN_PTR, 0);
454 		reserve = max(devctl_queue_length / 50, 100);	/* 2% reserve */
455 		uma_zone_set_max(z, devctl_queue_length);
456 		uma_zone_set_maxcache(z, 0);
457 		uma_zone_reserve(z, reserve);
458 		uma_prealloc(z, reserve);
459 	}
460 	devctl2_init();
461 }
462 
463 static int
464 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
465 {
466 	mtx_lock(&devsoftc.mtx);
467 	if (devsoftc.inuse) {
468 		mtx_unlock(&devsoftc.mtx);
469 		return (EBUSY);
470 	}
471 	/* move to init */
472 	devsoftc.inuse = 1;
473 	mtx_unlock(&devsoftc.mtx);
474 	return (0);
475 }
476 
477 static int
478 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
479 {
480 	mtx_lock(&devsoftc.mtx);
481 	devsoftc.inuse = 0;
482 	devsoftc.nonblock = 0;
483 	devsoftc.async = 0;
484 	cv_broadcast(&devsoftc.cv);
485 	funsetown(&devsoftc.sigio);
486 	mtx_unlock(&devsoftc.mtx);
487 	return (0);
488 }
489 
490 /*
491  * The read channel for this device is used to report changes to
492  * userland in realtime.  We are required to free the data as well as
493  * the n1 object because we allocate them separately.  Also note that
494  * we return one record at a time.  If you try to read this device a
495  * character at a time, you will lose the rest of the data.  Listening
496  * programs are expected to cope.
497  */
498 static int
499 devread(struct cdev *dev, struct uio *uio, int ioflag)
500 {
501 	struct dev_event_info *n1;
502 	int rv;
503 
504 	mtx_lock(&devsoftc.mtx);
505 	while (STAILQ_EMPTY(&devsoftc.devq)) {
506 		if (devsoftc.nonblock) {
507 			mtx_unlock(&devsoftc.mtx);
508 			return (EAGAIN);
509 		}
510 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
511 		if (rv) {
512 			/*
513 			 * Need to translate ERESTART to EINTR here? -- jake
514 			 */
515 			mtx_unlock(&devsoftc.mtx);
516 			return (rv);
517 		}
518 	}
519 	n1 = STAILQ_FIRST(&devsoftc.devq);
520 	STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
521 	devsoftc.queued--;
522 	mtx_unlock(&devsoftc.mtx);
523 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
524 	uma_zfree(devsoftc.zone, n1);
525 	return (rv);
526 }
527 
528 static	int
529 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
530 {
531 	switch (cmd) {
532 	case FIONBIO:
533 		if (*(int*)data)
534 			devsoftc.nonblock = 1;
535 		else
536 			devsoftc.nonblock = 0;
537 		return (0);
538 	case FIOASYNC:
539 		if (*(int*)data)
540 			devsoftc.async = 1;
541 		else
542 			devsoftc.async = 0;
543 		return (0);
544 	case FIOSETOWN:
545 		return fsetown(*(int *)data, &devsoftc.sigio);
546 	case FIOGETOWN:
547 		*(int *)data = fgetown(&devsoftc.sigio);
548 		return (0);
549 
550 		/* (un)Support for other fcntl() calls. */
551 	case FIOCLEX:
552 	case FIONCLEX:
553 	case FIONREAD:
554 	default:
555 		break;
556 	}
557 	return (ENOTTY);
558 }
559 
560 static	int
561 devpoll(struct cdev *dev, int events, struct thread *td)
562 {
563 	int	revents = 0;
564 
565 	mtx_lock(&devsoftc.mtx);
566 	if (events & (POLLIN | POLLRDNORM)) {
567 		if (!STAILQ_EMPTY(&devsoftc.devq))
568 			revents = events & (POLLIN | POLLRDNORM);
569 		else
570 			selrecord(td, &devsoftc.sel);
571 	}
572 	mtx_unlock(&devsoftc.mtx);
573 
574 	return (revents);
575 }
576 
577 static int
578 devkqfilter(struct cdev *dev, struct knote *kn)
579 {
580 	int error;
581 
582 	if (kn->kn_filter == EVFILT_READ) {
583 		kn->kn_fop = &devctl_rfiltops;
584 		knlist_add(&devsoftc.sel.si_note, kn, 0);
585 		error = 0;
586 	} else
587 		error = EINVAL;
588 	return (error);
589 }
590 
591 static void
592 filt_devctl_detach(struct knote *kn)
593 {
594 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
595 }
596 
597 static int
598 filt_devctl_read(struct knote *kn, long hint)
599 {
600 	kn->kn_data = devsoftc.queued;
601 	return (kn->kn_data != 0);
602 }
603 
604 /**
605  * @brief Return whether the userland process is running
606  */
607 bool
608 devctl_process_running(void)
609 {
610 	return (devsoftc.inuse == 1);
611 }
612 
613 static struct dev_event_info *
614 devctl_alloc_dei(void)
615 {
616 	struct dev_event_info *dei = NULL;
617 
618 	mtx_lock(&devsoftc.mtx);
619 	if (devctl_queue_length == 0)
620 		goto out;
621 	dei = uma_zalloc(devsoftc.zone, M_NOWAIT);
622 	if (dei == NULL)
623 		dei = uma_zalloc(devsoftc.zone, M_NOWAIT | M_USE_RESERVE);
624 	if (dei == NULL) {
625 		/*
626 		 * Guard against no items in the queue. Normally, this won't
627 		 * happen, but if lots of events happen all at once and there's
628 		 * a chance we're out of allocated space but none have yet been
629 		 * queued when we get here, leaving nothing to steal. This can
630 		 * also happen with error injection. Fail safe by returning
631 		 * NULL in that case..
632 		 */
633 		if (devsoftc.queued == 0)
634 			goto out;
635 		dei = STAILQ_FIRST(&devsoftc.devq);
636 		STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
637 		devsoftc.queued--;
638 	}
639 	MPASS(dei != NULL);
640 	*dei->dei_data = '\0';
641 out:
642 	mtx_unlock(&devsoftc.mtx);
643 	return (dei);
644 }
645 
646 static struct dev_event_info *
647 devctl_alloc_dei_sb(struct sbuf *sb)
648 {
649 	struct dev_event_info *dei;
650 
651 	dei = devctl_alloc_dei();
652 	if (dei != NULL)
653 		sbuf_new(sb, dei->dei_data, sizeof(dei->dei_data), SBUF_FIXEDLEN);
654 	return (dei);
655 }
656 
657 static void
658 devctl_free_dei(struct dev_event_info *dei)
659 {
660 	uma_zfree(devsoftc.zone, dei);
661 }
662 
663 static void
664 devctl_queue(struct dev_event_info *dei)
665 {
666 	mtx_lock(&devsoftc.mtx);
667 	STAILQ_INSERT_TAIL(&devsoftc.devq, dei, dei_link);
668 	devsoftc.queued++;
669 	cv_broadcast(&devsoftc.cv);
670 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
671 	mtx_unlock(&devsoftc.mtx);
672 	selwakeup(&devsoftc.sel);
673 	if (devsoftc.async && devsoftc.sigio != NULL)
674 		pgsigio(&devsoftc.sigio, SIGIO, 0);
675 }
676 
677 /**
678  * @brief Send a 'notification' to userland, using standard ways
679  */
680 void
681 devctl_notify(const char *system, const char *subsystem, const char *type,
682     const char *data)
683 {
684 	struct dev_event_info *dei;
685 	struct sbuf sb;
686 
687 	if (system == NULL || subsystem == NULL || type == NULL)
688 		return;
689 	dei = devctl_alloc_dei_sb(&sb);
690 	if (dei == NULL)
691 		return;
692 	sbuf_cpy(&sb, "!system=");
693 	sbuf_cat(&sb, system);
694 	sbuf_cat(&sb, " subsystem=");
695 	sbuf_cat(&sb, subsystem);
696 	sbuf_cat(&sb, " type=");
697 	sbuf_cat(&sb, type);
698 	if (data != NULL) {
699 		sbuf_putc(&sb, ' ');
700 		sbuf_cat(&sb, data);
701 	}
702 	sbuf_putc(&sb, '\n');
703 	if (sbuf_finish(&sb) != 0)
704 		devctl_free_dei(dei);	/* overflow -> drop it */
705 	else
706 		devctl_queue(dei);
707 }
708 
709 /*
710  * Common routine that tries to make sending messages as easy as possible.
711  * We allocate memory for the data, copy strings into that, but do not
712  * free it unless there's an error.  The dequeue part of the driver should
713  * free the data.  We don't send data when the device is disabled.  We do
714  * send data, even when we have no listeners, because we wish to avoid
715  * races relating to startup and restart of listening applications.
716  *
717  * devaddq is designed to string together the type of event, with the
718  * object of that event, plus the plug and play info and location info
719  * for that event.  This is likely most useful for devices, but less
720  * useful for other consumers of this interface.  Those should use
721  * the devctl_notify() interface instead.
722  *
723  * Output:
724  *	${type}${what} at $(location dev) $(pnp-info dev) on $(parent dev)
725  */
726 static void
727 devaddq(const char *type, const char *what, device_t dev)
728 {
729 	struct dev_event_info *dei;
730 	const char *parstr;
731 	struct sbuf sb;
732 
733 	dei = devctl_alloc_dei_sb(&sb);
734 	if (dei == NULL)
735 		return;
736 	sbuf_cpy(&sb, type);
737 	sbuf_cat(&sb, what);
738 	sbuf_cat(&sb, " at ");
739 
740 	/* Add in the location */
741 	bus_child_location(dev, &sb);
742 	sbuf_putc(&sb, ' ');
743 
744 	/* Add in pnpinfo */
745 	bus_child_pnpinfo(dev, &sb);
746 
747 	/* Get the parent of this device, or / if high enough in the tree. */
748 	if (device_get_parent(dev) == NULL)
749 		parstr = ".";	/* Or '/' ? */
750 	else
751 		parstr = device_get_nameunit(device_get_parent(dev));
752 	sbuf_cat(&sb, " on ");
753 	sbuf_cat(&sb, parstr);
754 	sbuf_putc(&sb, '\n');
755 	if (sbuf_finish(&sb) != 0)
756 		goto bad;
757 	devctl_queue(dei);
758 	return;
759 bad:
760 	devctl_free_dei(dei);
761 }
762 
763 /*
764  * A device was added to the tree.  We are called just after it successfully
765  * attaches (that is, probe and attach success for this device).  No call
766  * is made if a device is merely parented into the tree.  See devnomatch
767  * if probe fails.  If attach fails, no notification is sent (but maybe
768  * we should have a different message for this).
769  */
770 static void
771 devadded(device_t dev)
772 {
773 	devaddq("+", device_get_nameunit(dev), dev);
774 }
775 
776 /*
777  * A device was removed from the tree.  We are called just before this
778  * happens.
779  */
780 static void
781 devremoved(device_t dev)
782 {
783 	devaddq("-", device_get_nameunit(dev), dev);
784 }
785 
786 /*
787  * Called when there's no match for this device.  This is only called
788  * the first time that no match happens, so we don't keep getting this
789  * message.  Should that prove to be undesirable, we can change it.
790  * This is called when all drivers that can attach to a given bus
791  * decline to accept this device.  Other errors may not be detected.
792  */
793 static void
794 devnomatch(device_t dev)
795 {
796 	devaddq("?", "", dev);
797 }
798 
799 static int
800 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
801 {
802 	int q, error;
803 
804 	q = devctl_queue_length;
805 	error = sysctl_handle_int(oidp, &q, 0, req);
806 	if (error || !req->newptr)
807 		return (error);
808 	if (q < 0)
809 		return (EINVAL);
810 
811 	/*
812 	 * When set as a tunable, we've not yet initialized the mutex.
813 	 * It is safe to just assign to devctl_queue_length and return
814 	 * as we're racing no one. We'll use whatever value set in
815 	 * devinit.
816 	 */
817 	if (!mtx_initialized(&devsoftc.mtx)) {
818 		devctl_queue_length = q;
819 		return (0);
820 	}
821 
822 	/*
823 	 * XXX It's hard to grow or shrink the UMA zone. Only allow
824 	 * disabling the queue size for the moment until underlying
825 	 * UMA issues can be sorted out.
826 	 */
827 	if (q != 0)
828 		return (EINVAL);
829 	if (q == devctl_queue_length)
830 		return (0);
831 	mtx_lock(&devsoftc.mtx);
832 	devctl_queue_length = 0;
833 	uma_zdestroy(devsoftc.zone);
834 	devsoftc.zone = 0;
835 	mtx_unlock(&devsoftc.mtx);
836 	return (0);
837 }
838 
839 /**
840  * @brief safely quotes strings that might have double quotes in them.
841  *
842  * The devctl protocol relies on quoted strings having matching quotes.
843  * This routine quotes any internal quotes so the resulting string
844  * is safe to pass to snprintf to construct, for example pnp info strings.
845  *
846  * @param sb	sbuf to place the characters into
847  * @param src	Original buffer.
848  */
849 void
850 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
851 {
852 	while (*src != '\0') {
853 		if (*src == '"' || *src == '\\')
854 			sbuf_putc(sb, '\\');
855 		sbuf_putc(sb, *src++);
856 	}
857 }
858 
859 /* End of /dev/devctl code */
860 
861 static struct device_list bus_data_devices;
862 static int bus_data_generation = 1;
863 
864 static kobj_method_t null_methods[] = {
865 	KOBJMETHOD_END
866 };
867 
868 DEFINE_CLASS(null, null_methods, 0);
869 
870 void
871 bus_topo_assert()
872 {
873 
874 	GIANT_REQUIRED;
875 }
876 
877 struct mtx *
878 bus_topo_mtx(void)
879 {
880 
881 	return (&Giant);
882 }
883 
884 void
885 bus_topo_lock(void)
886 {
887 
888 	mtx_lock(bus_topo_mtx());
889 }
890 
891 void
892 bus_topo_unlock(void)
893 {
894 
895 	mtx_unlock(bus_topo_mtx());
896 }
897 
898 /*
899  * Bus pass implementation
900  */
901 
902 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
903 int bus_current_pass = BUS_PASS_ROOT;
904 
905 /**
906  * @internal
907  * @brief Register the pass level of a new driver attachment
908  *
909  * Register a new driver attachment's pass level.  If no driver
910  * attachment with the same pass level has been added, then @p new
911  * will be added to the global passes list.
912  *
913  * @param new		the new driver attachment
914  */
915 static void
916 driver_register_pass(struct driverlink *new)
917 {
918 	struct driverlink *dl;
919 
920 	/* We only consider pass numbers during boot. */
921 	if (bus_current_pass == BUS_PASS_DEFAULT)
922 		return;
923 
924 	/*
925 	 * Walk the passes list.  If we already know about this pass
926 	 * then there is nothing to do.  If we don't, then insert this
927 	 * driver link into the list.
928 	 */
929 	TAILQ_FOREACH(dl, &passes, passlink) {
930 		if (dl->pass < new->pass)
931 			continue;
932 		if (dl->pass == new->pass)
933 			return;
934 		TAILQ_INSERT_BEFORE(dl, new, passlink);
935 		return;
936 	}
937 	TAILQ_INSERT_TAIL(&passes, new, passlink);
938 }
939 
940 /**
941  * @brief Raise the current bus pass
942  *
943  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
944  * method on the root bus to kick off a new device tree scan for each
945  * new pass level that has at least one driver.
946  */
947 void
948 bus_set_pass(int pass)
949 {
950 	struct driverlink *dl;
951 
952 	if (bus_current_pass > pass)
953 		panic("Attempt to lower bus pass level");
954 
955 	TAILQ_FOREACH(dl, &passes, passlink) {
956 		/* Skip pass values below the current pass level. */
957 		if (dl->pass <= bus_current_pass)
958 			continue;
959 
960 		/*
961 		 * Bail once we hit a driver with a pass level that is
962 		 * too high.
963 		 */
964 		if (dl->pass > pass)
965 			break;
966 
967 		/*
968 		 * Raise the pass level to the next level and rescan
969 		 * the tree.
970 		 */
971 		bus_current_pass = dl->pass;
972 		BUS_NEW_PASS(root_bus);
973 	}
974 
975 	/*
976 	 * If there isn't a driver registered for the requested pass,
977 	 * then bus_current_pass might still be less than 'pass'.  Set
978 	 * it to 'pass' in that case.
979 	 */
980 	if (bus_current_pass < pass)
981 		bus_current_pass = pass;
982 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
983 }
984 
985 /*
986  * Devclass implementation
987  */
988 
989 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
990 
991 /**
992  * @internal
993  * @brief Find or create a device class
994  *
995  * If a device class with the name @p classname exists, return it,
996  * otherwise if @p create is non-zero create and return a new device
997  * class.
998  *
999  * If @p parentname is non-NULL, the parent of the devclass is set to
1000  * the devclass of that name.
1001  *
1002  * @param classname	the devclass name to find or create
1003  * @param parentname	the parent devclass name or @c NULL
1004  * @param create	non-zero to create a devclass
1005  */
1006 static devclass_t
1007 devclass_find_internal(const char *classname, const char *parentname,
1008 		       int create)
1009 {
1010 	devclass_t dc;
1011 
1012 	PDEBUG(("looking for %s", classname));
1013 	if (!classname)
1014 		return (NULL);
1015 
1016 	TAILQ_FOREACH(dc, &devclasses, link) {
1017 		if (!strcmp(dc->name, classname))
1018 			break;
1019 	}
1020 
1021 	if (create && !dc) {
1022 		PDEBUG(("creating %s", classname));
1023 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
1024 		    M_BUS, M_NOWAIT | M_ZERO);
1025 		if (!dc)
1026 			return (NULL);
1027 		dc->parent = NULL;
1028 		dc->name = (char*) (dc + 1);
1029 		strcpy(dc->name, classname);
1030 		TAILQ_INIT(&dc->drivers);
1031 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
1032 
1033 		bus_data_generation_update();
1034 	}
1035 
1036 	/*
1037 	 * If a parent class is specified, then set that as our parent so
1038 	 * that this devclass will support drivers for the parent class as
1039 	 * well.  If the parent class has the same name don't do this though
1040 	 * as it creates a cycle that can trigger an infinite loop in
1041 	 * device_probe_child() if a device exists for which there is no
1042 	 * suitable driver.
1043 	 */
1044 	if (parentname && dc && !dc->parent &&
1045 	    strcmp(classname, parentname) != 0) {
1046 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1047 		dc->parent->flags |= DC_HAS_CHILDREN;
1048 	}
1049 
1050 	return (dc);
1051 }
1052 
1053 /**
1054  * @brief Create a device class
1055  *
1056  * If a device class with the name @p classname exists, return it,
1057  * otherwise create and return a new device class.
1058  *
1059  * @param classname	the devclass name to find or create
1060  */
1061 devclass_t
1062 devclass_create(const char *classname)
1063 {
1064 	return (devclass_find_internal(classname, NULL, TRUE));
1065 }
1066 
1067 /**
1068  * @brief Find a device class
1069  *
1070  * If a device class with the name @p classname exists, return it,
1071  * otherwise return @c NULL.
1072  *
1073  * @param classname	the devclass name to find
1074  */
1075 devclass_t
1076 devclass_find(const char *classname)
1077 {
1078 	return (devclass_find_internal(classname, NULL, FALSE));
1079 }
1080 
1081 /**
1082  * @brief Register that a device driver has been added to a devclass
1083  *
1084  * Register that a device driver has been added to a devclass.  This
1085  * is called by devclass_add_driver to accomplish the recursive
1086  * notification of all the children classes of dc, as well as dc.
1087  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1088  * the devclass.
1089  *
1090  * We do a full search here of the devclass list at each iteration
1091  * level to save storing children-lists in the devclass structure.  If
1092  * we ever move beyond a few dozen devices doing this, we may need to
1093  * reevaluate...
1094  *
1095  * @param dc		the devclass to edit
1096  * @param driver	the driver that was just added
1097  */
1098 static void
1099 devclass_driver_added(devclass_t dc, driver_t *driver)
1100 {
1101 	devclass_t parent;
1102 	int i;
1103 
1104 	/*
1105 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1106 	 */
1107 	for (i = 0; i < dc->maxunit; i++)
1108 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1109 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1110 
1111 	/*
1112 	 * Walk through the children classes.  Since we only keep a
1113 	 * single parent pointer around, we walk the entire list of
1114 	 * devclasses looking for children.  We set the
1115 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1116 	 * the parent, so we only walk the list for those devclasses
1117 	 * that have children.
1118 	 */
1119 	if (!(dc->flags & DC_HAS_CHILDREN))
1120 		return;
1121 	parent = dc;
1122 	TAILQ_FOREACH(dc, &devclasses, link) {
1123 		if (dc->parent == parent)
1124 			devclass_driver_added(dc, driver);
1125 	}
1126 }
1127 
1128 /**
1129  * @brief Add a device driver to a device class
1130  *
1131  * Add a device driver to a devclass. This is normally called
1132  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1133  * all devices in the devclass will be called to allow them to attempt
1134  * to re-probe any unmatched children.
1135  *
1136  * @param dc		the devclass to edit
1137  * @param driver	the driver to register
1138  */
1139 int
1140 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1141 {
1142 	driverlink_t dl;
1143 	const char *parentname;
1144 
1145 	PDEBUG(("%s", DRIVERNAME(driver)));
1146 
1147 	/* Don't allow invalid pass values. */
1148 	if (pass <= BUS_PASS_ROOT)
1149 		return (EINVAL);
1150 
1151 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1152 	if (!dl)
1153 		return (ENOMEM);
1154 
1155 	/*
1156 	 * Compile the driver's methods. Also increase the reference count
1157 	 * so that the class doesn't get freed when the last instance
1158 	 * goes. This means we can safely use static methods and avoids a
1159 	 * double-free in devclass_delete_driver.
1160 	 */
1161 	kobj_class_compile((kobj_class_t) driver);
1162 
1163 	/*
1164 	 * If the driver has any base classes, make the
1165 	 * devclass inherit from the devclass of the driver's
1166 	 * first base class. This will allow the system to
1167 	 * search for drivers in both devclasses for children
1168 	 * of a device using this driver.
1169 	 */
1170 	if (driver->baseclasses)
1171 		parentname = driver->baseclasses[0]->name;
1172 	else
1173 		parentname = NULL;
1174 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1175 
1176 	dl->driver = driver;
1177 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1178 	driver->refs++;		/* XXX: kobj_mtx */
1179 	dl->pass = pass;
1180 	driver_register_pass(dl);
1181 
1182 	if (device_frozen) {
1183 		dl->flags |= DL_DEFERRED_PROBE;
1184 	} else {
1185 		devclass_driver_added(dc, driver);
1186 	}
1187 	bus_data_generation_update();
1188 	return (0);
1189 }
1190 
1191 /**
1192  * @brief Register that a device driver has been deleted from a devclass
1193  *
1194  * Register that a device driver has been removed from a devclass.
1195  * This is called by devclass_delete_driver to accomplish the
1196  * recursive notification of all the children classes of busclass, as
1197  * well as busclass.  Each layer will attempt to detach the driver
1198  * from any devices that are children of the bus's devclass.  The function
1199  * will return an error if a device fails to detach.
1200  *
1201  * We do a full search here of the devclass list at each iteration
1202  * level to save storing children-lists in the devclass structure.  If
1203  * we ever move beyond a few dozen devices doing this, we may need to
1204  * reevaluate...
1205  *
1206  * @param busclass	the devclass of the parent bus
1207  * @param dc		the devclass of the driver being deleted
1208  * @param driver	the driver being deleted
1209  */
1210 static int
1211 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1212 {
1213 	devclass_t parent;
1214 	device_t dev;
1215 	int error, i;
1216 
1217 	/*
1218 	 * Disassociate from any devices.  We iterate through all the
1219 	 * devices in the devclass of the driver and detach any which are
1220 	 * using the driver and which have a parent in the devclass which
1221 	 * we are deleting from.
1222 	 *
1223 	 * Note that since a driver can be in multiple devclasses, we
1224 	 * should not detach devices which are not children of devices in
1225 	 * the affected devclass.
1226 	 *
1227 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1228 	 * generate later.
1229 	 */
1230 	for (i = 0; i < dc->maxunit; i++) {
1231 		if (dc->devices[i]) {
1232 			dev = dc->devices[i];
1233 			if (dev->driver == driver && dev->parent &&
1234 			    dev->parent->devclass == busclass) {
1235 				if ((error = device_detach(dev)) != 0)
1236 					return (error);
1237 				if (device_frozen) {
1238 					dev->flags &= ~DF_DONENOMATCH;
1239 					dev->flags |= DF_NEEDNOMATCH;
1240 				} else {
1241 					BUS_PROBE_NOMATCH(dev->parent, dev);
1242 					devnomatch(dev);
1243 					dev->flags |= DF_DONENOMATCH;
1244 				}
1245 			}
1246 		}
1247 	}
1248 
1249 	/*
1250 	 * Walk through the children classes.  Since we only keep a
1251 	 * single parent pointer around, we walk the entire list of
1252 	 * devclasses looking for children.  We set the
1253 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1254 	 * the parent, so we only walk the list for those devclasses
1255 	 * that have children.
1256 	 */
1257 	if (!(busclass->flags & DC_HAS_CHILDREN))
1258 		return (0);
1259 	parent = busclass;
1260 	TAILQ_FOREACH(busclass, &devclasses, link) {
1261 		if (busclass->parent == parent) {
1262 			error = devclass_driver_deleted(busclass, dc, driver);
1263 			if (error)
1264 				return (error);
1265 		}
1266 	}
1267 	return (0);
1268 }
1269 
1270 /**
1271  * @brief Delete a device driver from a device class
1272  *
1273  * Delete a device driver from a devclass. This is normally called
1274  * automatically by DRIVER_MODULE().
1275  *
1276  * If the driver is currently attached to any devices,
1277  * devclass_delete_driver() will first attempt to detach from each
1278  * device. If one of the detach calls fails, the driver will not be
1279  * deleted.
1280  *
1281  * @param dc		the devclass to edit
1282  * @param driver	the driver to unregister
1283  */
1284 int
1285 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1286 {
1287 	devclass_t dc = devclass_find(driver->name);
1288 	driverlink_t dl;
1289 	int error;
1290 
1291 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1292 
1293 	if (!dc)
1294 		return (0);
1295 
1296 	/*
1297 	 * Find the link structure in the bus' list of drivers.
1298 	 */
1299 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1300 		if (dl->driver == driver)
1301 			break;
1302 	}
1303 
1304 	if (!dl) {
1305 		PDEBUG(("%s not found in %s list", driver->name,
1306 		    busclass->name));
1307 		return (ENOENT);
1308 	}
1309 
1310 	error = devclass_driver_deleted(busclass, dc, driver);
1311 	if (error != 0)
1312 		return (error);
1313 
1314 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1315 	free(dl, M_BUS);
1316 
1317 	/* XXX: kobj_mtx */
1318 	driver->refs--;
1319 	if (driver->refs == 0)
1320 		kobj_class_free((kobj_class_t) driver);
1321 
1322 	bus_data_generation_update();
1323 	return (0);
1324 }
1325 
1326 /**
1327  * @brief Quiesces a set of device drivers from a device class
1328  *
1329  * Quiesce a device driver from a devclass. This is normally called
1330  * automatically by DRIVER_MODULE().
1331  *
1332  * If the driver is currently attached to any devices,
1333  * devclass_quiesece_driver() will first attempt to quiesce each
1334  * device.
1335  *
1336  * @param dc		the devclass to edit
1337  * @param driver	the driver to unregister
1338  */
1339 static int
1340 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1341 {
1342 	devclass_t dc = devclass_find(driver->name);
1343 	driverlink_t dl;
1344 	device_t dev;
1345 	int i;
1346 	int error;
1347 
1348 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1349 
1350 	if (!dc)
1351 		return (0);
1352 
1353 	/*
1354 	 * Find the link structure in the bus' list of drivers.
1355 	 */
1356 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1357 		if (dl->driver == driver)
1358 			break;
1359 	}
1360 
1361 	if (!dl) {
1362 		PDEBUG(("%s not found in %s list", driver->name,
1363 		    busclass->name));
1364 		return (ENOENT);
1365 	}
1366 
1367 	/*
1368 	 * Quiesce all devices.  We iterate through all the devices in
1369 	 * the devclass of the driver and quiesce any which are using
1370 	 * the driver and which have a parent in the devclass which we
1371 	 * are quiescing.
1372 	 *
1373 	 * Note that since a driver can be in multiple devclasses, we
1374 	 * should not quiesce devices which are not children of
1375 	 * devices in the affected devclass.
1376 	 */
1377 	for (i = 0; i < dc->maxunit; i++) {
1378 		if (dc->devices[i]) {
1379 			dev = dc->devices[i];
1380 			if (dev->driver == driver && dev->parent &&
1381 			    dev->parent->devclass == busclass) {
1382 				if ((error = device_quiesce(dev)) != 0)
1383 					return (error);
1384 			}
1385 		}
1386 	}
1387 
1388 	return (0);
1389 }
1390 
1391 /**
1392  * @internal
1393  */
1394 static driverlink_t
1395 devclass_find_driver_internal(devclass_t dc, const char *classname)
1396 {
1397 	driverlink_t dl;
1398 
1399 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1400 
1401 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1402 		if (!strcmp(dl->driver->name, classname))
1403 			return (dl);
1404 	}
1405 
1406 	PDEBUG(("not found"));
1407 	return (NULL);
1408 }
1409 
1410 /**
1411  * @brief Return the name of the devclass
1412  */
1413 const char *
1414 devclass_get_name(devclass_t dc)
1415 {
1416 	return (dc->name);
1417 }
1418 
1419 /**
1420  * @brief Find a device given a unit number
1421  *
1422  * @param dc		the devclass to search
1423  * @param unit		the unit number to search for
1424  *
1425  * @returns		the device with the given unit number or @c
1426  *			NULL if there is no such device
1427  */
1428 device_t
1429 devclass_get_device(devclass_t dc, int unit)
1430 {
1431 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1432 		return (NULL);
1433 	return (dc->devices[unit]);
1434 }
1435 
1436 /**
1437  * @brief Find the softc field of a device given a unit number
1438  *
1439  * @param dc		the devclass to search
1440  * @param unit		the unit number to search for
1441  *
1442  * @returns		the softc field of the device with the given
1443  *			unit number or @c NULL if there is no such
1444  *			device
1445  */
1446 void *
1447 devclass_get_softc(devclass_t dc, int unit)
1448 {
1449 	device_t dev;
1450 
1451 	dev = devclass_get_device(dc, unit);
1452 	if (!dev)
1453 		return (NULL);
1454 
1455 	return (device_get_softc(dev));
1456 }
1457 
1458 /**
1459  * @brief Get a list of devices in the devclass
1460  *
1461  * An array containing a list of all the devices in the given devclass
1462  * is allocated and returned in @p *devlistp. The number of devices
1463  * in the array is returned in @p *devcountp. The caller should free
1464  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1465  *
1466  * @param dc		the devclass to examine
1467  * @param devlistp	points at location for array pointer return
1468  *			value
1469  * @param devcountp	points at location for array size return value
1470  *
1471  * @retval 0		success
1472  * @retval ENOMEM	the array allocation failed
1473  */
1474 int
1475 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1476 {
1477 	int count, i;
1478 	device_t *list;
1479 
1480 	count = devclass_get_count(dc);
1481 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1482 	if (!list)
1483 		return (ENOMEM);
1484 
1485 	count = 0;
1486 	for (i = 0; i < dc->maxunit; i++) {
1487 		if (dc->devices[i]) {
1488 			list[count] = dc->devices[i];
1489 			count++;
1490 		}
1491 	}
1492 
1493 	*devlistp = list;
1494 	*devcountp = count;
1495 
1496 	return (0);
1497 }
1498 
1499 /**
1500  * @brief Get a list of drivers in the devclass
1501  *
1502  * An array containing a list of pointers to all the drivers in the
1503  * given devclass is allocated and returned in @p *listp.  The number
1504  * of drivers in the array is returned in @p *countp. The caller should
1505  * free the array using @c free(p, M_TEMP).
1506  *
1507  * @param dc		the devclass to examine
1508  * @param listp		gives location for array pointer return value
1509  * @param countp	gives location for number of array elements
1510  *			return value
1511  *
1512  * @retval 0		success
1513  * @retval ENOMEM	the array allocation failed
1514  */
1515 int
1516 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1517 {
1518 	driverlink_t dl;
1519 	driver_t **list;
1520 	int count;
1521 
1522 	count = 0;
1523 	TAILQ_FOREACH(dl, &dc->drivers, link)
1524 		count++;
1525 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1526 	if (list == NULL)
1527 		return (ENOMEM);
1528 
1529 	count = 0;
1530 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1531 		list[count] = dl->driver;
1532 		count++;
1533 	}
1534 	*listp = list;
1535 	*countp = count;
1536 
1537 	return (0);
1538 }
1539 
1540 /**
1541  * @brief Get the number of devices in a devclass
1542  *
1543  * @param dc		the devclass to examine
1544  */
1545 int
1546 devclass_get_count(devclass_t dc)
1547 {
1548 	int count, i;
1549 
1550 	count = 0;
1551 	for (i = 0; i < dc->maxunit; i++)
1552 		if (dc->devices[i])
1553 			count++;
1554 	return (count);
1555 }
1556 
1557 /**
1558  * @brief Get the maximum unit number used in a devclass
1559  *
1560  * Note that this is one greater than the highest currently-allocated
1561  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1562  * that not even the devclass has been allocated yet.
1563  *
1564  * @param dc		the devclass to examine
1565  */
1566 int
1567 devclass_get_maxunit(devclass_t dc)
1568 {
1569 	if (dc == NULL)
1570 		return (-1);
1571 	return (dc->maxunit);
1572 }
1573 
1574 /**
1575  * @brief Find a free unit number in a devclass
1576  *
1577  * This function searches for the first unused unit number greater
1578  * that or equal to @p unit.
1579  *
1580  * @param dc		the devclass to examine
1581  * @param unit		the first unit number to check
1582  */
1583 int
1584 devclass_find_free_unit(devclass_t dc, int unit)
1585 {
1586 	if (dc == NULL)
1587 		return (unit);
1588 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1589 		unit++;
1590 	return (unit);
1591 }
1592 
1593 /**
1594  * @brief Set the parent of a devclass
1595  *
1596  * The parent class is normally initialised automatically by
1597  * DRIVER_MODULE().
1598  *
1599  * @param dc		the devclass to edit
1600  * @param pdc		the new parent devclass
1601  */
1602 void
1603 devclass_set_parent(devclass_t dc, devclass_t pdc)
1604 {
1605 	dc->parent = pdc;
1606 }
1607 
1608 /**
1609  * @brief Get the parent of a devclass
1610  *
1611  * @param dc		the devclass to examine
1612  */
1613 devclass_t
1614 devclass_get_parent(devclass_t dc)
1615 {
1616 	return (dc->parent);
1617 }
1618 
1619 struct sysctl_ctx_list *
1620 devclass_get_sysctl_ctx(devclass_t dc)
1621 {
1622 	return (&dc->sysctl_ctx);
1623 }
1624 
1625 struct sysctl_oid *
1626 devclass_get_sysctl_tree(devclass_t dc)
1627 {
1628 	return (dc->sysctl_tree);
1629 }
1630 
1631 /**
1632  * @internal
1633  * @brief Allocate a unit number
1634  *
1635  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1636  * will do). The allocated unit number is returned in @p *unitp.
1637 
1638  * @param dc		the devclass to allocate from
1639  * @param unitp		points at the location for the allocated unit
1640  *			number
1641  *
1642  * @retval 0		success
1643  * @retval EEXIST	the requested unit number is already allocated
1644  * @retval ENOMEM	memory allocation failure
1645  */
1646 static int
1647 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1648 {
1649 	const char *s;
1650 	int unit = *unitp;
1651 
1652 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1653 
1654 	/* Ask the parent bus if it wants to wire this device. */
1655 	if (unit == -1)
1656 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1657 		    &unit);
1658 
1659 	/* If we were given a wired unit number, check for existing device */
1660 	/* XXX imp XXX */
1661 	if (unit != -1) {
1662 		if (unit >= 0 && unit < dc->maxunit &&
1663 		    dc->devices[unit] != NULL) {
1664 			if (bootverbose)
1665 				printf("%s: %s%d already exists; skipping it\n",
1666 				    dc->name, dc->name, *unitp);
1667 			return (EEXIST);
1668 		}
1669 	} else {
1670 		/* Unwired device, find the next available slot for it */
1671 		unit = 0;
1672 		for (unit = 0;; unit++) {
1673 			/* If this device slot is already in use, skip it. */
1674 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1675 				continue;
1676 
1677 			/* If there is an "at" hint for a unit then skip it. */
1678 			if (resource_string_value(dc->name, unit, "at", &s) ==
1679 			    0)
1680 				continue;
1681 
1682 			break;
1683 		}
1684 	}
1685 
1686 	/*
1687 	 * We've selected a unit beyond the length of the table, so let's
1688 	 * extend the table to make room for all units up to and including
1689 	 * this one.
1690 	 */
1691 	if (unit >= dc->maxunit) {
1692 		device_t *newlist, *oldlist;
1693 		int newsize;
1694 
1695 		oldlist = dc->devices;
1696 		newsize = roundup((unit + 1),
1697 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1698 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1699 		if (!newlist)
1700 			return (ENOMEM);
1701 		if (oldlist != NULL)
1702 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1703 		bzero(newlist + dc->maxunit,
1704 		    sizeof(device_t) * (newsize - dc->maxunit));
1705 		dc->devices = newlist;
1706 		dc->maxunit = newsize;
1707 		if (oldlist != NULL)
1708 			free(oldlist, M_BUS);
1709 	}
1710 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1711 
1712 	*unitp = unit;
1713 	return (0);
1714 }
1715 
1716 /**
1717  * @internal
1718  * @brief Add a device to a devclass
1719  *
1720  * A unit number is allocated for the device (using the device's
1721  * preferred unit number if any) and the device is registered in the
1722  * devclass. This allows the device to be looked up by its unit
1723  * number, e.g. by decoding a dev_t minor number.
1724  *
1725  * @param dc		the devclass to add to
1726  * @param dev		the device to add
1727  *
1728  * @retval 0		success
1729  * @retval EEXIST	the requested unit number is already allocated
1730  * @retval ENOMEM	memory allocation failure
1731  */
1732 static int
1733 devclass_add_device(devclass_t dc, device_t dev)
1734 {
1735 	int buflen, error;
1736 
1737 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1738 
1739 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1740 	if (buflen < 0)
1741 		return (ENOMEM);
1742 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1743 	if (!dev->nameunit)
1744 		return (ENOMEM);
1745 
1746 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1747 		free(dev->nameunit, M_BUS);
1748 		dev->nameunit = NULL;
1749 		return (error);
1750 	}
1751 	dc->devices[dev->unit] = dev;
1752 	dev->devclass = dc;
1753 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1754 
1755 	return (0);
1756 }
1757 
1758 /**
1759  * @internal
1760  * @brief Delete a device from a devclass
1761  *
1762  * The device is removed from the devclass's device list and its unit
1763  * number is freed.
1764 
1765  * @param dc		the devclass to delete from
1766  * @param dev		the device to delete
1767  *
1768  * @retval 0		success
1769  */
1770 static int
1771 devclass_delete_device(devclass_t dc, device_t dev)
1772 {
1773 	if (!dc || !dev)
1774 		return (0);
1775 
1776 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1777 
1778 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1779 		panic("devclass_delete_device: inconsistent device class");
1780 	dc->devices[dev->unit] = NULL;
1781 	if (dev->flags & DF_WILDCARD)
1782 		dev->unit = -1;
1783 	dev->devclass = NULL;
1784 	free(dev->nameunit, M_BUS);
1785 	dev->nameunit = NULL;
1786 
1787 	return (0);
1788 }
1789 
1790 /**
1791  * @internal
1792  * @brief Make a new device and add it as a child of @p parent
1793  *
1794  * @param parent	the parent of the new device
1795  * @param name		the devclass name of the new device or @c NULL
1796  *			to leave the devclass unspecified
1797  * @parem unit		the unit number of the new device of @c -1 to
1798  *			leave the unit number unspecified
1799  *
1800  * @returns the new device
1801  */
1802 static device_t
1803 make_device(device_t parent, const char *name, int unit)
1804 {
1805 	device_t dev;
1806 	devclass_t dc;
1807 
1808 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1809 
1810 	if (name) {
1811 		dc = devclass_find_internal(name, NULL, TRUE);
1812 		if (!dc) {
1813 			printf("make_device: can't find device class %s\n",
1814 			    name);
1815 			return (NULL);
1816 		}
1817 	} else {
1818 		dc = NULL;
1819 	}
1820 
1821 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1822 	if (!dev)
1823 		return (NULL);
1824 
1825 	dev->parent = parent;
1826 	TAILQ_INIT(&dev->children);
1827 	kobj_init((kobj_t) dev, &null_class);
1828 	dev->driver = NULL;
1829 	dev->devclass = NULL;
1830 	dev->unit = unit;
1831 	dev->nameunit = NULL;
1832 	dev->desc = NULL;
1833 	dev->busy = 0;
1834 	dev->devflags = 0;
1835 	dev->flags = DF_ENABLED;
1836 	dev->order = 0;
1837 	if (unit == -1)
1838 		dev->flags |= DF_WILDCARD;
1839 	if (name) {
1840 		dev->flags |= DF_FIXEDCLASS;
1841 		if (devclass_add_device(dc, dev)) {
1842 			kobj_delete((kobj_t) dev, M_BUS);
1843 			return (NULL);
1844 		}
1845 	}
1846 	if (parent != NULL && device_has_quiet_children(parent))
1847 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1848 	dev->ivars = NULL;
1849 	dev->softc = NULL;
1850 
1851 	dev->state = DS_NOTPRESENT;
1852 
1853 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1854 	bus_data_generation_update();
1855 
1856 	return (dev);
1857 }
1858 
1859 /**
1860  * @internal
1861  * @brief Print a description of a device.
1862  */
1863 static int
1864 device_print_child(device_t dev, device_t child)
1865 {
1866 	int retval = 0;
1867 
1868 	if (device_is_alive(child))
1869 		retval += BUS_PRINT_CHILD(dev, child);
1870 	else
1871 		retval += device_printf(child, " not found\n");
1872 
1873 	return (retval);
1874 }
1875 
1876 /**
1877  * @brief Create a new device
1878  *
1879  * This creates a new device and adds it as a child of an existing
1880  * parent device. The new device will be added after the last existing
1881  * child with order zero.
1882  *
1883  * @param dev		the device which will be the parent of the
1884  *			new child device
1885  * @param name		devclass name for new device or @c NULL if not
1886  *			specified
1887  * @param unit		unit number for new device or @c -1 if not
1888  *			specified
1889  *
1890  * @returns		the new device
1891  */
1892 device_t
1893 device_add_child(device_t dev, const char *name, int unit)
1894 {
1895 	return (device_add_child_ordered(dev, 0, name, unit));
1896 }
1897 
1898 /**
1899  * @brief Create a new device
1900  *
1901  * This creates a new device and adds it as a child of an existing
1902  * parent device. The new device will be added after the last existing
1903  * child with the same order.
1904  *
1905  * @param dev		the device which will be the parent of the
1906  *			new child device
1907  * @param order		a value which is used to partially sort the
1908  *			children of @p dev - devices created using
1909  *			lower values of @p order appear first in @p
1910  *			dev's list of children
1911  * @param name		devclass name for new device or @c NULL if not
1912  *			specified
1913  * @param unit		unit number for new device or @c -1 if not
1914  *			specified
1915  *
1916  * @returns		the new device
1917  */
1918 device_t
1919 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1920 {
1921 	device_t child;
1922 	device_t place;
1923 
1924 	PDEBUG(("%s at %s with order %u as unit %d",
1925 	    name, DEVICENAME(dev), order, unit));
1926 	KASSERT(name != NULL || unit == -1,
1927 	    ("child device with wildcard name and specific unit number"));
1928 
1929 	child = make_device(dev, name, unit);
1930 	if (child == NULL)
1931 		return (child);
1932 	child->order = order;
1933 
1934 	TAILQ_FOREACH(place, &dev->children, link) {
1935 		if (place->order > order)
1936 			break;
1937 	}
1938 
1939 	if (place) {
1940 		/*
1941 		 * The device 'place' is the first device whose order is
1942 		 * greater than the new child.
1943 		 */
1944 		TAILQ_INSERT_BEFORE(place, child, link);
1945 	} else {
1946 		/*
1947 		 * The new child's order is greater or equal to the order of
1948 		 * any existing device. Add the child to the tail of the list.
1949 		 */
1950 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1951 	}
1952 
1953 	bus_data_generation_update();
1954 	return (child);
1955 }
1956 
1957 /**
1958  * @brief Delete a device
1959  *
1960  * This function deletes a device along with all of its children. If
1961  * the device currently has a driver attached to it, the device is
1962  * detached first using device_detach().
1963  *
1964  * @param dev		the parent device
1965  * @param child		the device to delete
1966  *
1967  * @retval 0		success
1968  * @retval non-zero	a unit error code describing the error
1969  */
1970 int
1971 device_delete_child(device_t dev, device_t child)
1972 {
1973 	int error;
1974 	device_t grandchild;
1975 
1976 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1977 
1978 	/* detach parent before deleting children, if any */
1979 	if ((error = device_detach(child)) != 0)
1980 		return (error);
1981 
1982 	/* remove children second */
1983 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1984 		error = device_delete_child(child, grandchild);
1985 		if (error)
1986 			return (error);
1987 	}
1988 
1989 	if (child->devclass)
1990 		devclass_delete_device(child->devclass, child);
1991 	if (child->parent)
1992 		BUS_CHILD_DELETED(dev, child);
1993 	TAILQ_REMOVE(&dev->children, child, link);
1994 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1995 	kobj_delete((kobj_t) child, M_BUS);
1996 
1997 	bus_data_generation_update();
1998 	return (0);
1999 }
2000 
2001 /**
2002  * @brief Delete all children devices of the given device, if any.
2003  *
2004  * This function deletes all children devices of the given device, if
2005  * any, using the device_delete_child() function for each device it
2006  * finds. If a child device cannot be deleted, this function will
2007  * return an error code.
2008  *
2009  * @param dev		the parent device
2010  *
2011  * @retval 0		success
2012  * @retval non-zero	a device would not detach
2013  */
2014 int
2015 device_delete_children(device_t dev)
2016 {
2017 	device_t child;
2018 	int error;
2019 
2020 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
2021 
2022 	error = 0;
2023 
2024 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
2025 		error = device_delete_child(dev, child);
2026 		if (error) {
2027 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
2028 			break;
2029 		}
2030 	}
2031 	return (error);
2032 }
2033 
2034 /**
2035  * @brief Find a device given a unit number
2036  *
2037  * This is similar to devclass_get_devices() but only searches for
2038  * devices which have @p dev as a parent.
2039  *
2040  * @param dev		the parent device to search
2041  * @param unit		the unit number to search for.  If the unit is -1,
2042  *			return the first child of @p dev which has name
2043  *			@p classname (that is, the one with the lowest unit.)
2044  *
2045  * @returns		the device with the given unit number or @c
2046  *			NULL if there is no such device
2047  */
2048 device_t
2049 device_find_child(device_t dev, const char *classname, int unit)
2050 {
2051 	devclass_t dc;
2052 	device_t child;
2053 
2054 	dc = devclass_find(classname);
2055 	if (!dc)
2056 		return (NULL);
2057 
2058 	if (unit != -1) {
2059 		child = devclass_get_device(dc, unit);
2060 		if (child && child->parent == dev)
2061 			return (child);
2062 	} else {
2063 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2064 			child = devclass_get_device(dc, unit);
2065 			if (child && child->parent == dev)
2066 				return (child);
2067 		}
2068 	}
2069 	return (NULL);
2070 }
2071 
2072 /**
2073  * @internal
2074  */
2075 static driverlink_t
2076 first_matching_driver(devclass_t dc, device_t dev)
2077 {
2078 	if (dev->devclass)
2079 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2080 	return (TAILQ_FIRST(&dc->drivers));
2081 }
2082 
2083 /**
2084  * @internal
2085  */
2086 static driverlink_t
2087 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2088 {
2089 	if (dev->devclass) {
2090 		driverlink_t dl;
2091 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2092 			if (!strcmp(dev->devclass->name, dl->driver->name))
2093 				return (dl);
2094 		return (NULL);
2095 	}
2096 	return (TAILQ_NEXT(last, link));
2097 }
2098 
2099 /**
2100  * @internal
2101  */
2102 int
2103 device_probe_child(device_t dev, device_t child)
2104 {
2105 	devclass_t dc;
2106 	driverlink_t best = NULL;
2107 	driverlink_t dl;
2108 	int result, pri = 0;
2109 	/* We should preserve the devclass (or lack of) set by the bus. */
2110 	int hasclass = (child->devclass != NULL);
2111 
2112 	bus_topo_assert();
2113 
2114 	dc = dev->devclass;
2115 	if (!dc)
2116 		panic("device_probe_child: parent device has no devclass");
2117 
2118 	/*
2119 	 * If the state is already probed, then return.
2120 	 */
2121 	if (child->state == DS_ALIVE)
2122 		return (0);
2123 
2124 	for (; dc; dc = dc->parent) {
2125 		for (dl = first_matching_driver(dc, child);
2126 		     dl;
2127 		     dl = next_matching_driver(dc, child, dl)) {
2128 			/* If this driver's pass is too high, then ignore it. */
2129 			if (dl->pass > bus_current_pass)
2130 				continue;
2131 
2132 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2133 			result = device_set_driver(child, dl->driver);
2134 			if (result == ENOMEM)
2135 				return (result);
2136 			else if (result != 0)
2137 				continue;
2138 			if (!hasclass) {
2139 				if (device_set_devclass(child,
2140 				    dl->driver->name) != 0) {
2141 					char const * devname =
2142 					    device_get_name(child);
2143 					if (devname == NULL)
2144 						devname = "(unknown)";
2145 					printf("driver bug: Unable to set "
2146 					    "devclass (class: %s "
2147 					    "devname: %s)\n",
2148 					    dl->driver->name,
2149 					    devname);
2150 					(void)device_set_driver(child, NULL);
2151 					continue;
2152 				}
2153 			}
2154 
2155 			/* Fetch any flags for the device before probing. */
2156 			resource_int_value(dl->driver->name, child->unit,
2157 			    "flags", &child->devflags);
2158 
2159 			result = DEVICE_PROBE(child);
2160 
2161 			/*
2162 			 * If the driver returns SUCCESS, there can be
2163 			 * no higher match for this device.
2164 			 */
2165 			if (result == 0) {
2166 				best = dl;
2167 				pri = 0;
2168 				break;
2169 			}
2170 
2171 			/* Reset flags and devclass before the next probe. */
2172 			child->devflags = 0;
2173 			if (!hasclass)
2174 				(void)device_set_devclass(child, NULL);
2175 
2176 			/*
2177 			 * Reset DF_QUIET in case this driver doesn't
2178 			 * end up as the best driver.
2179 			 */
2180 			device_verbose(child);
2181 
2182 			/*
2183 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2184 			 * only match on devices whose driver was explicitly
2185 			 * specified.
2186 			 */
2187 			if (result <= BUS_PROBE_NOWILDCARD &&
2188 			    !(child->flags & DF_FIXEDCLASS)) {
2189 				result = ENXIO;
2190 			}
2191 
2192 			/*
2193 			 * The driver returned an error so it
2194 			 * certainly doesn't match.
2195 			 */
2196 			if (result > 0) {
2197 				(void)device_set_driver(child, NULL);
2198 				continue;
2199 			}
2200 
2201 			/*
2202 			 * A priority lower than SUCCESS, remember the
2203 			 * best matching driver. Initialise the value
2204 			 * of pri for the first match.
2205 			 */
2206 			if (best == NULL || result > pri) {
2207 				best = dl;
2208 				pri = result;
2209 				continue;
2210 			}
2211 		}
2212 		/*
2213 		 * If we have an unambiguous match in this devclass,
2214 		 * don't look in the parent.
2215 		 */
2216 		if (best && pri == 0)
2217 			break;
2218 	}
2219 
2220 	if (best == NULL)
2221 		return (ENXIO);
2222 
2223 	/*
2224 	 * If we found a driver, change state and initialise the devclass.
2225 	 */
2226 	if (pri < 0) {
2227 		/* Set the winning driver, devclass, and flags. */
2228 		result = device_set_driver(child, best->driver);
2229 		if (result != 0)
2230 			return (result);
2231 		if (!child->devclass) {
2232 			result = device_set_devclass(child, best->driver->name);
2233 			if (result != 0) {
2234 				(void)device_set_driver(child, NULL);
2235 				return (result);
2236 			}
2237 		}
2238 		resource_int_value(best->driver->name, child->unit,
2239 		    "flags", &child->devflags);
2240 
2241 		/*
2242 		 * A bit bogus. Call the probe method again to make sure
2243 		 * that we have the right description.
2244 		 */
2245 		result = DEVICE_PROBE(child);
2246 		if (result > 0) {
2247 			if (!hasclass)
2248 				(void)device_set_devclass(child, NULL);
2249 			(void)device_set_driver(child, NULL);
2250 			return (result);
2251 		}
2252 	}
2253 
2254 	child->state = DS_ALIVE;
2255 	bus_data_generation_update();
2256 	return (0);
2257 }
2258 
2259 /**
2260  * @brief Return the parent of a device
2261  */
2262 device_t
2263 device_get_parent(device_t dev)
2264 {
2265 	return (dev->parent);
2266 }
2267 
2268 /**
2269  * @brief Get a list of children of a device
2270  *
2271  * An array containing a list of all the children of the given device
2272  * is allocated and returned in @p *devlistp. The number of devices
2273  * in the array is returned in @p *devcountp. The caller should free
2274  * the array using @c free(p, M_TEMP).
2275  *
2276  * @param dev		the device to examine
2277  * @param devlistp	points at location for array pointer return
2278  *			value
2279  * @param devcountp	points at location for array size return value
2280  *
2281  * @retval 0		success
2282  * @retval ENOMEM	the array allocation failed
2283  */
2284 int
2285 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2286 {
2287 	int count;
2288 	device_t child;
2289 	device_t *list;
2290 
2291 	count = 0;
2292 	TAILQ_FOREACH(child, &dev->children, link) {
2293 		count++;
2294 	}
2295 	if (count == 0) {
2296 		*devlistp = NULL;
2297 		*devcountp = 0;
2298 		return (0);
2299 	}
2300 
2301 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2302 	if (!list)
2303 		return (ENOMEM);
2304 
2305 	count = 0;
2306 	TAILQ_FOREACH(child, &dev->children, link) {
2307 		list[count] = child;
2308 		count++;
2309 	}
2310 
2311 	*devlistp = list;
2312 	*devcountp = count;
2313 
2314 	return (0);
2315 }
2316 
2317 /**
2318  * @brief Return the current driver for the device or @c NULL if there
2319  * is no driver currently attached
2320  */
2321 driver_t *
2322 device_get_driver(device_t dev)
2323 {
2324 	return (dev->driver);
2325 }
2326 
2327 /**
2328  * @brief Return the current devclass for the device or @c NULL if
2329  * there is none.
2330  */
2331 devclass_t
2332 device_get_devclass(device_t dev)
2333 {
2334 	return (dev->devclass);
2335 }
2336 
2337 /**
2338  * @brief Return the name of the device's devclass or @c NULL if there
2339  * is none.
2340  */
2341 const char *
2342 device_get_name(device_t dev)
2343 {
2344 	if (dev != NULL && dev->devclass)
2345 		return (devclass_get_name(dev->devclass));
2346 	return (NULL);
2347 }
2348 
2349 /**
2350  * @brief Return a string containing the device's devclass name
2351  * followed by an ascii representation of the device's unit number
2352  * (e.g. @c "foo2").
2353  */
2354 const char *
2355 device_get_nameunit(device_t dev)
2356 {
2357 	return (dev->nameunit);
2358 }
2359 
2360 /**
2361  * @brief Return the device's unit number.
2362  */
2363 int
2364 device_get_unit(device_t dev)
2365 {
2366 	return (dev->unit);
2367 }
2368 
2369 /**
2370  * @brief Return the device's description string
2371  */
2372 const char *
2373 device_get_desc(device_t dev)
2374 {
2375 	return (dev->desc);
2376 }
2377 
2378 /**
2379  * @brief Return the device's flags
2380  */
2381 uint32_t
2382 device_get_flags(device_t dev)
2383 {
2384 	return (dev->devflags);
2385 }
2386 
2387 struct sysctl_ctx_list *
2388 device_get_sysctl_ctx(device_t dev)
2389 {
2390 	return (&dev->sysctl_ctx);
2391 }
2392 
2393 struct sysctl_oid *
2394 device_get_sysctl_tree(device_t dev)
2395 {
2396 	return (dev->sysctl_tree);
2397 }
2398 
2399 /**
2400  * @brief Print the name of the device followed by a colon and a space
2401  *
2402  * @returns the number of characters printed
2403  */
2404 int
2405 device_print_prettyname(device_t dev)
2406 {
2407 	const char *name = device_get_name(dev);
2408 
2409 	if (name == NULL)
2410 		return (printf("unknown: "));
2411 	return (printf("%s%d: ", name, device_get_unit(dev)));
2412 }
2413 
2414 /**
2415  * @brief Print the name of the device followed by a colon, a space
2416  * and the result of calling vprintf() with the value of @p fmt and
2417  * the following arguments.
2418  *
2419  * @returns the number of characters printed
2420  */
2421 int
2422 device_printf(device_t dev, const char * fmt, ...)
2423 {
2424 	char buf[128];
2425 	struct sbuf sb;
2426 	const char *name;
2427 	va_list ap;
2428 	size_t retval;
2429 
2430 	retval = 0;
2431 
2432 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2433 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2434 
2435 	name = device_get_name(dev);
2436 
2437 	if (name == NULL)
2438 		sbuf_cat(&sb, "unknown: ");
2439 	else
2440 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2441 
2442 	va_start(ap, fmt);
2443 	sbuf_vprintf(&sb, fmt, ap);
2444 	va_end(ap);
2445 
2446 	sbuf_finish(&sb);
2447 	sbuf_delete(&sb);
2448 
2449 	return (retval);
2450 }
2451 
2452 /**
2453  * @brief Print the name of the device followed by a colon, a space
2454  * and the result of calling log() with the value of @p fmt and
2455  * the following arguments.
2456  *
2457  * @returns the number of characters printed
2458  */
2459 int
2460 device_log(device_t dev, int pri, const char * fmt, ...)
2461 {
2462 	char buf[128];
2463 	struct sbuf sb;
2464 	const char *name;
2465 	va_list ap;
2466 	size_t retval;
2467 
2468 	retval = 0;
2469 
2470 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2471 
2472 	name = device_get_name(dev);
2473 
2474 	if (name == NULL)
2475 		sbuf_cat(&sb, "unknown: ");
2476 	else
2477 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2478 
2479 	va_start(ap, fmt);
2480 	sbuf_vprintf(&sb, fmt, ap);
2481 	va_end(ap);
2482 
2483 	sbuf_finish(&sb);
2484 
2485 	log(pri, "%.*s", (int) sbuf_len(&sb), sbuf_data(&sb));
2486 	retval = sbuf_len(&sb);
2487 
2488 	sbuf_delete(&sb);
2489 
2490 	return (retval);
2491 }
2492 
2493 /**
2494  * @internal
2495  */
2496 static void
2497 device_set_desc_internal(device_t dev, const char* desc, int copy)
2498 {
2499 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2500 		free(dev->desc, M_BUS);
2501 		dev->flags &= ~DF_DESCMALLOCED;
2502 		dev->desc = NULL;
2503 	}
2504 
2505 	if (copy && desc) {
2506 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2507 		if (dev->desc) {
2508 			strcpy(dev->desc, desc);
2509 			dev->flags |= DF_DESCMALLOCED;
2510 		}
2511 	} else {
2512 		/* Avoid a -Wcast-qual warning */
2513 		dev->desc = (char *)(uintptr_t) desc;
2514 	}
2515 
2516 	bus_data_generation_update();
2517 }
2518 
2519 /**
2520  * @brief Set the device's description
2521  *
2522  * The value of @c desc should be a string constant that will not
2523  * change (at least until the description is changed in a subsequent
2524  * call to device_set_desc() or device_set_desc_copy()).
2525  */
2526 void
2527 device_set_desc(device_t dev, const char* desc)
2528 {
2529 	device_set_desc_internal(dev, desc, FALSE);
2530 }
2531 
2532 /**
2533  * @brief Set the device's description
2534  *
2535  * The string pointed to by @c desc is copied. Use this function if
2536  * the device description is generated, (e.g. with sprintf()).
2537  */
2538 void
2539 device_set_desc_copy(device_t dev, const char* desc)
2540 {
2541 	device_set_desc_internal(dev, desc, TRUE);
2542 }
2543 
2544 /**
2545  * @brief Set the device's flags
2546  */
2547 void
2548 device_set_flags(device_t dev, uint32_t flags)
2549 {
2550 	dev->devflags = flags;
2551 }
2552 
2553 /**
2554  * @brief Return the device's softc field
2555  *
2556  * The softc is allocated and zeroed when a driver is attached, based
2557  * on the size field of the driver.
2558  */
2559 void *
2560 device_get_softc(device_t dev)
2561 {
2562 	return (dev->softc);
2563 }
2564 
2565 /**
2566  * @brief Set the device's softc field
2567  *
2568  * Most drivers do not need to use this since the softc is allocated
2569  * automatically when the driver is attached.
2570  */
2571 void
2572 device_set_softc(device_t dev, void *softc)
2573 {
2574 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2575 		free(dev->softc, M_BUS_SC);
2576 	dev->softc = softc;
2577 	if (dev->softc)
2578 		dev->flags |= DF_EXTERNALSOFTC;
2579 	else
2580 		dev->flags &= ~DF_EXTERNALSOFTC;
2581 }
2582 
2583 /**
2584  * @brief Free claimed softc
2585  *
2586  * Most drivers do not need to use this since the softc is freed
2587  * automatically when the driver is detached.
2588  */
2589 void
2590 device_free_softc(void *softc)
2591 {
2592 	free(softc, M_BUS_SC);
2593 }
2594 
2595 /**
2596  * @brief Claim softc
2597  *
2598  * This function can be used to let the driver free the automatically
2599  * allocated softc using "device_free_softc()". This function is
2600  * useful when the driver is refcounting the softc and the softc
2601  * cannot be freed when the "device_detach" method is called.
2602  */
2603 void
2604 device_claim_softc(device_t dev)
2605 {
2606 	if (dev->softc)
2607 		dev->flags |= DF_EXTERNALSOFTC;
2608 	else
2609 		dev->flags &= ~DF_EXTERNALSOFTC;
2610 }
2611 
2612 /**
2613  * @brief Get the device's ivars field
2614  *
2615  * The ivars field is used by the parent device to store per-device
2616  * state (e.g. the physical location of the device or a list of
2617  * resources).
2618  */
2619 void *
2620 device_get_ivars(device_t dev)
2621 {
2622 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2623 	return (dev->ivars);
2624 }
2625 
2626 /**
2627  * @brief Set the device's ivars field
2628  */
2629 void
2630 device_set_ivars(device_t dev, void * ivars)
2631 {
2632 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2633 	dev->ivars = ivars;
2634 }
2635 
2636 /**
2637  * @brief Return the device's state
2638  */
2639 device_state_t
2640 device_get_state(device_t dev)
2641 {
2642 	return (dev->state);
2643 }
2644 
2645 /**
2646  * @brief Set the DF_ENABLED flag for the device
2647  */
2648 void
2649 device_enable(device_t dev)
2650 {
2651 	dev->flags |= DF_ENABLED;
2652 }
2653 
2654 /**
2655  * @brief Clear the DF_ENABLED flag for the device
2656  */
2657 void
2658 device_disable(device_t dev)
2659 {
2660 	dev->flags &= ~DF_ENABLED;
2661 }
2662 
2663 /**
2664  * @brief Increment the busy counter for the device
2665  */
2666 void
2667 device_busy(device_t dev)
2668 {
2669 
2670 	/*
2671 	 * Mark the device as busy, recursively up the tree if this busy count
2672 	 * goes 0->1.
2673 	 */
2674 	if (refcount_acquire(&dev->busy) == 0 && dev->parent != NULL)
2675 		device_busy(dev->parent);
2676 }
2677 
2678 /**
2679  * @brief Decrement the busy counter for the device
2680  */
2681 void
2682 device_unbusy(device_t dev)
2683 {
2684 
2685 	/*
2686 	 * Mark the device as unbsy, recursively if this is the last busy count.
2687 	 */
2688 	if (refcount_release(&dev->busy) && dev->parent != NULL)
2689 		device_unbusy(dev->parent);
2690 }
2691 
2692 /**
2693  * @brief Set the DF_QUIET flag for the device
2694  */
2695 void
2696 device_quiet(device_t dev)
2697 {
2698 	dev->flags |= DF_QUIET;
2699 }
2700 
2701 /**
2702  * @brief Set the DF_QUIET_CHILDREN flag for the device
2703  */
2704 void
2705 device_quiet_children(device_t dev)
2706 {
2707 	dev->flags |= DF_QUIET_CHILDREN;
2708 }
2709 
2710 /**
2711  * @brief Clear the DF_QUIET flag for the device
2712  */
2713 void
2714 device_verbose(device_t dev)
2715 {
2716 	dev->flags &= ~DF_QUIET;
2717 }
2718 
2719 ssize_t
2720 device_get_property(device_t dev, const char *prop, void *val, size_t sz)
2721 {
2722 	device_t bus = device_get_parent(dev);
2723 
2724 	return (BUS_GET_PROPERTY(bus, dev, prop, val, sz));
2725 }
2726 
2727 bool
2728 device_has_property(device_t dev, const char *prop)
2729 {
2730 	return (device_get_property(dev, prop, NULL, 0) >= 0);
2731 }
2732 
2733 /**
2734  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2735  */
2736 int
2737 device_has_quiet_children(device_t dev)
2738 {
2739 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2740 }
2741 
2742 /**
2743  * @brief Return non-zero if the DF_QUIET flag is set on the device
2744  */
2745 int
2746 device_is_quiet(device_t dev)
2747 {
2748 	return ((dev->flags & DF_QUIET) != 0);
2749 }
2750 
2751 /**
2752  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2753  */
2754 int
2755 device_is_enabled(device_t dev)
2756 {
2757 	return ((dev->flags & DF_ENABLED) != 0);
2758 }
2759 
2760 /**
2761  * @brief Return non-zero if the device was successfully probed
2762  */
2763 int
2764 device_is_alive(device_t dev)
2765 {
2766 	return (dev->state >= DS_ALIVE);
2767 }
2768 
2769 /**
2770  * @brief Return non-zero if the device currently has a driver
2771  * attached to it
2772  */
2773 int
2774 device_is_attached(device_t dev)
2775 {
2776 	return (dev->state >= DS_ATTACHED);
2777 }
2778 
2779 /**
2780  * @brief Return non-zero if the device is currently suspended.
2781  */
2782 int
2783 device_is_suspended(device_t dev)
2784 {
2785 	return ((dev->flags & DF_SUSPENDED) != 0);
2786 }
2787 
2788 /**
2789  * @brief Set the devclass of a device
2790  * @see devclass_add_device().
2791  */
2792 int
2793 device_set_devclass(device_t dev, const char *classname)
2794 {
2795 	devclass_t dc;
2796 	int error;
2797 
2798 	if (!classname) {
2799 		if (dev->devclass)
2800 			devclass_delete_device(dev->devclass, dev);
2801 		return (0);
2802 	}
2803 
2804 	if (dev->devclass) {
2805 		printf("device_set_devclass: device class already set\n");
2806 		return (EINVAL);
2807 	}
2808 
2809 	dc = devclass_find_internal(classname, NULL, TRUE);
2810 	if (!dc)
2811 		return (ENOMEM);
2812 
2813 	error = devclass_add_device(dc, dev);
2814 
2815 	bus_data_generation_update();
2816 	return (error);
2817 }
2818 
2819 /**
2820  * @brief Set the devclass of a device and mark the devclass fixed.
2821  * @see device_set_devclass()
2822  */
2823 int
2824 device_set_devclass_fixed(device_t dev, const char *classname)
2825 {
2826 	int error;
2827 
2828 	if (classname == NULL)
2829 		return (EINVAL);
2830 
2831 	error = device_set_devclass(dev, classname);
2832 	if (error)
2833 		return (error);
2834 	dev->flags |= DF_FIXEDCLASS;
2835 	return (0);
2836 }
2837 
2838 /**
2839  * @brief Query the device to determine if it's of a fixed devclass
2840  * @see device_set_devclass_fixed()
2841  */
2842 bool
2843 device_is_devclass_fixed(device_t dev)
2844 {
2845 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2846 }
2847 
2848 /**
2849  * @brief Set the driver of a device
2850  *
2851  * @retval 0		success
2852  * @retval EBUSY	the device already has a driver attached
2853  * @retval ENOMEM	a memory allocation failure occurred
2854  */
2855 int
2856 device_set_driver(device_t dev, driver_t *driver)
2857 {
2858 	int domain;
2859 	struct domainset *policy;
2860 
2861 	if (dev->state >= DS_ATTACHED)
2862 		return (EBUSY);
2863 
2864 	if (dev->driver == driver)
2865 		return (0);
2866 
2867 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2868 		free(dev->softc, M_BUS_SC);
2869 		dev->softc = NULL;
2870 	}
2871 	device_set_desc(dev, NULL);
2872 	kobj_delete((kobj_t) dev, NULL);
2873 	dev->driver = driver;
2874 	if (driver) {
2875 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2876 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2877 			if (bus_get_domain(dev, &domain) == 0)
2878 				policy = DOMAINSET_PREF(domain);
2879 			else
2880 				policy = DOMAINSET_RR();
2881 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2882 			    policy, M_NOWAIT | M_ZERO);
2883 			if (!dev->softc) {
2884 				kobj_delete((kobj_t) dev, NULL);
2885 				kobj_init((kobj_t) dev, &null_class);
2886 				dev->driver = NULL;
2887 				return (ENOMEM);
2888 			}
2889 		}
2890 	} else {
2891 		kobj_init((kobj_t) dev, &null_class);
2892 	}
2893 
2894 	bus_data_generation_update();
2895 	return (0);
2896 }
2897 
2898 /**
2899  * @brief Probe a device, and return this status.
2900  *
2901  * This function is the core of the device autoconfiguration
2902  * system. Its purpose is to select a suitable driver for a device and
2903  * then call that driver to initialise the hardware appropriately. The
2904  * driver is selected by calling the DEVICE_PROBE() method of a set of
2905  * candidate drivers and then choosing the driver which returned the
2906  * best value. This driver is then attached to the device using
2907  * device_attach().
2908  *
2909  * The set of suitable drivers is taken from the list of drivers in
2910  * the parent device's devclass. If the device was originally created
2911  * with a specific class name (see device_add_child()), only drivers
2912  * with that name are probed, otherwise all drivers in the devclass
2913  * are probed. If no drivers return successful probe values in the
2914  * parent devclass, the search continues in the parent of that
2915  * devclass (see devclass_get_parent()) if any.
2916  *
2917  * @param dev		the device to initialise
2918  *
2919  * @retval 0		success
2920  * @retval ENXIO	no driver was found
2921  * @retval ENOMEM	memory allocation failure
2922  * @retval non-zero	some other unix error code
2923  * @retval -1		Device already attached
2924  */
2925 int
2926 device_probe(device_t dev)
2927 {
2928 	int error;
2929 
2930 	bus_topo_assert();
2931 
2932 	if (dev->state >= DS_ALIVE)
2933 		return (-1);
2934 
2935 	if (!(dev->flags & DF_ENABLED)) {
2936 		if (bootverbose && device_get_name(dev) != NULL) {
2937 			device_print_prettyname(dev);
2938 			printf("not probed (disabled)\n");
2939 		}
2940 		return (-1);
2941 	}
2942 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2943 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2944 		    !(dev->flags & DF_DONENOMATCH)) {
2945 			BUS_PROBE_NOMATCH(dev->parent, dev);
2946 			devnomatch(dev);
2947 			dev->flags |= DF_DONENOMATCH;
2948 		}
2949 		return (error);
2950 	}
2951 	return (0);
2952 }
2953 
2954 /**
2955  * @brief Probe a device and attach a driver if possible
2956  *
2957  * calls device_probe() and attaches if that was successful.
2958  */
2959 int
2960 device_probe_and_attach(device_t dev)
2961 {
2962 	int error;
2963 
2964 	bus_topo_assert();
2965 
2966 	error = device_probe(dev);
2967 	if (error == -1)
2968 		return (0);
2969 	else if (error != 0)
2970 		return (error);
2971 
2972 	CURVNET_SET_QUIET(vnet0);
2973 	error = device_attach(dev);
2974 	CURVNET_RESTORE();
2975 	return error;
2976 }
2977 
2978 /**
2979  * @brief Attach a device driver to a device
2980  *
2981  * This function is a wrapper around the DEVICE_ATTACH() driver
2982  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2983  * device's sysctl tree, optionally prints a description of the device
2984  * and queues a notification event for user-based device management
2985  * services.
2986  *
2987  * Normally this function is only called internally from
2988  * device_probe_and_attach().
2989  *
2990  * @param dev		the device to initialise
2991  *
2992  * @retval 0		success
2993  * @retval ENXIO	no driver was found
2994  * @retval ENOMEM	memory allocation failure
2995  * @retval non-zero	some other unix error code
2996  */
2997 int
2998 device_attach(device_t dev)
2999 {
3000 	uint64_t attachtime;
3001 	uint16_t attachentropy;
3002 	int error;
3003 
3004 	if (resource_disabled(dev->driver->name, dev->unit)) {
3005 		device_disable(dev);
3006 		if (bootverbose)
3007 			 device_printf(dev, "disabled via hints entry\n");
3008 		return (ENXIO);
3009 	}
3010 
3011 	device_sysctl_init(dev);
3012 	if (!device_is_quiet(dev))
3013 		device_print_child(dev->parent, dev);
3014 	attachtime = get_cyclecount();
3015 	dev->state = DS_ATTACHING;
3016 	if ((error = DEVICE_ATTACH(dev)) != 0) {
3017 		printf("device_attach: %s%d attach returned %d\n",
3018 		    dev->driver->name, dev->unit, error);
3019 		if (!(dev->flags & DF_FIXEDCLASS))
3020 			devclass_delete_device(dev->devclass, dev);
3021 		(void)device_set_driver(dev, NULL);
3022 		device_sysctl_fini(dev);
3023 		KASSERT(dev->busy == 0, ("attach failed but busy"));
3024 		dev->state = DS_NOTPRESENT;
3025 		return (error);
3026 	}
3027 	dev->flags |= DF_ATTACHED_ONCE;
3028 	/* We only need the low bits of this time, but ranges from tens to thousands
3029 	 * have been seen, so keep 2 bytes' worth.
3030 	 */
3031 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3032 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3033 	device_sysctl_update(dev);
3034 	dev->state = DS_ATTACHED;
3035 	dev->flags &= ~DF_DONENOMATCH;
3036 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3037 	devadded(dev);
3038 	return (0);
3039 }
3040 
3041 /**
3042  * @brief Detach a driver from a device
3043  *
3044  * This function is a wrapper around the DEVICE_DETACH() driver
3045  * method. If the call to DEVICE_DETACH() succeeds, it calls
3046  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3047  * notification event for user-based device management services and
3048  * cleans up the device's sysctl tree.
3049  *
3050  * @param dev		the device to un-initialise
3051  *
3052  * @retval 0		success
3053  * @retval ENXIO	no driver was found
3054  * @retval ENOMEM	memory allocation failure
3055  * @retval non-zero	some other unix error code
3056  */
3057 int
3058 device_detach(device_t dev)
3059 {
3060 	int error;
3061 
3062 	bus_topo_assert();
3063 
3064 	PDEBUG(("%s", DEVICENAME(dev)));
3065 	if (dev->busy > 0)
3066 		return (EBUSY);
3067 	if (dev->state == DS_ATTACHING) {
3068 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3069 		return (EBUSY);
3070 	}
3071 	if (dev->state != DS_ATTACHED)
3072 		return (0);
3073 
3074 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3075 	if ((error = DEVICE_DETACH(dev)) != 0) {
3076 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3077 		    EVHDEV_DETACH_FAILED);
3078 		return (error);
3079 	} else {
3080 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3081 		    EVHDEV_DETACH_COMPLETE);
3082 	}
3083 	devremoved(dev);
3084 	if (!device_is_quiet(dev))
3085 		device_printf(dev, "detached\n");
3086 	if (dev->parent)
3087 		BUS_CHILD_DETACHED(dev->parent, dev);
3088 
3089 	if (!(dev->flags & DF_FIXEDCLASS))
3090 		devclass_delete_device(dev->devclass, dev);
3091 
3092 	device_verbose(dev);
3093 	dev->state = DS_NOTPRESENT;
3094 	(void)device_set_driver(dev, NULL);
3095 	device_sysctl_fini(dev);
3096 
3097 	return (0);
3098 }
3099 
3100 /**
3101  * @brief Tells a driver to quiesce itself.
3102  *
3103  * This function is a wrapper around the DEVICE_QUIESCE() driver
3104  * method. If the call to DEVICE_QUIESCE() succeeds.
3105  *
3106  * @param dev		the device to quiesce
3107  *
3108  * @retval 0		success
3109  * @retval ENXIO	no driver was found
3110  * @retval ENOMEM	memory allocation failure
3111  * @retval non-zero	some other unix error code
3112  */
3113 int
3114 device_quiesce(device_t dev)
3115 {
3116 	PDEBUG(("%s", DEVICENAME(dev)));
3117 	if (dev->busy > 0)
3118 		return (EBUSY);
3119 	if (dev->state != DS_ATTACHED)
3120 		return (0);
3121 
3122 	return (DEVICE_QUIESCE(dev));
3123 }
3124 
3125 /**
3126  * @brief Notify a device of system shutdown
3127  *
3128  * This function calls the DEVICE_SHUTDOWN() driver method if the
3129  * device currently has an attached driver.
3130  *
3131  * @returns the value returned by DEVICE_SHUTDOWN()
3132  */
3133 int
3134 device_shutdown(device_t dev)
3135 {
3136 	if (dev->state < DS_ATTACHED)
3137 		return (0);
3138 	return (DEVICE_SHUTDOWN(dev));
3139 }
3140 
3141 /**
3142  * @brief Set the unit number of a device
3143  *
3144  * This function can be used to override the unit number used for a
3145  * device (e.g. to wire a device to a pre-configured unit number).
3146  */
3147 int
3148 device_set_unit(device_t dev, int unit)
3149 {
3150 	devclass_t dc;
3151 	int err;
3152 
3153 	if (unit == dev->unit)
3154 		return (0);
3155 	dc = device_get_devclass(dev);
3156 	if (unit < dc->maxunit && dc->devices[unit])
3157 		return (EBUSY);
3158 	err = devclass_delete_device(dc, dev);
3159 	if (err)
3160 		return (err);
3161 	dev->unit = unit;
3162 	err = devclass_add_device(dc, dev);
3163 	if (err)
3164 		return (err);
3165 
3166 	bus_data_generation_update();
3167 	return (0);
3168 }
3169 
3170 /*======================================*/
3171 /*
3172  * Some useful method implementations to make life easier for bus drivers.
3173  */
3174 
3175 void
3176 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3177 {
3178 	bzero(args, sz);
3179 	args->size = sz;
3180 	args->memattr = VM_MEMATTR_DEVICE;
3181 }
3182 
3183 /**
3184  * @brief Initialise a resource list.
3185  *
3186  * @param rl		the resource list to initialise
3187  */
3188 void
3189 resource_list_init(struct resource_list *rl)
3190 {
3191 	STAILQ_INIT(rl);
3192 }
3193 
3194 /**
3195  * @brief Reclaim memory used by a resource list.
3196  *
3197  * This function frees the memory for all resource entries on the list
3198  * (if any).
3199  *
3200  * @param rl		the resource list to free
3201  */
3202 void
3203 resource_list_free(struct resource_list *rl)
3204 {
3205 	struct resource_list_entry *rle;
3206 
3207 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3208 		if (rle->res)
3209 			panic("resource_list_free: resource entry is busy");
3210 		STAILQ_REMOVE_HEAD(rl, link);
3211 		free(rle, M_BUS);
3212 	}
3213 }
3214 
3215 /**
3216  * @brief Add a resource entry.
3217  *
3218  * This function adds a resource entry using the given @p type, @p
3219  * start, @p end and @p count values. A rid value is chosen by
3220  * searching sequentially for the first unused rid starting at zero.
3221  *
3222  * @param rl		the resource list to edit
3223  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3224  * @param start		the start address of the resource
3225  * @param end		the end address of the resource
3226  * @param count		XXX end-start+1
3227  */
3228 int
3229 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3230     rman_res_t end, rman_res_t count)
3231 {
3232 	int rid;
3233 
3234 	rid = 0;
3235 	while (resource_list_find(rl, type, rid) != NULL)
3236 		rid++;
3237 	resource_list_add(rl, type, rid, start, end, count);
3238 	return (rid);
3239 }
3240 
3241 /**
3242  * @brief Add or modify a resource entry.
3243  *
3244  * If an existing entry exists with the same type and rid, it will be
3245  * modified using the given values of @p start, @p end and @p
3246  * count. If no entry exists, a new one will be created using the
3247  * given values.  The resource list entry that matches is then returned.
3248  *
3249  * @param rl		the resource list to edit
3250  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3251  * @param rid		the resource identifier
3252  * @param start		the start address of the resource
3253  * @param end		the end address of the resource
3254  * @param count		XXX end-start+1
3255  */
3256 struct resource_list_entry *
3257 resource_list_add(struct resource_list *rl, int type, int rid,
3258     rman_res_t start, rman_res_t end, rman_res_t count)
3259 {
3260 	struct resource_list_entry *rle;
3261 
3262 	rle = resource_list_find(rl, type, rid);
3263 	if (!rle) {
3264 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3265 		    M_NOWAIT);
3266 		if (!rle)
3267 			panic("resource_list_add: can't record entry");
3268 		STAILQ_INSERT_TAIL(rl, rle, link);
3269 		rle->type = type;
3270 		rle->rid = rid;
3271 		rle->res = NULL;
3272 		rle->flags = 0;
3273 	}
3274 
3275 	if (rle->res)
3276 		panic("resource_list_add: resource entry is busy");
3277 
3278 	rle->start = start;
3279 	rle->end = end;
3280 	rle->count = count;
3281 	return (rle);
3282 }
3283 
3284 /**
3285  * @brief Determine if a resource entry is busy.
3286  *
3287  * Returns true if a resource entry is busy meaning that it has an
3288  * associated resource that is not an unallocated "reserved" resource.
3289  *
3290  * @param rl		the resource list to search
3291  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3292  * @param rid		the resource identifier
3293  *
3294  * @returns Non-zero if the entry is busy, zero otherwise.
3295  */
3296 int
3297 resource_list_busy(struct resource_list *rl, int type, int rid)
3298 {
3299 	struct resource_list_entry *rle;
3300 
3301 	rle = resource_list_find(rl, type, rid);
3302 	if (rle == NULL || rle->res == NULL)
3303 		return (0);
3304 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3305 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3306 		    ("reserved resource is active"));
3307 		return (0);
3308 	}
3309 	return (1);
3310 }
3311 
3312 /**
3313  * @brief Determine if a resource entry is reserved.
3314  *
3315  * Returns true if a resource entry is reserved meaning that it has an
3316  * associated "reserved" resource.  The resource can either be
3317  * allocated or unallocated.
3318  *
3319  * @param rl		the resource list to search
3320  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3321  * @param rid		the resource identifier
3322  *
3323  * @returns Non-zero if the entry is reserved, zero otherwise.
3324  */
3325 int
3326 resource_list_reserved(struct resource_list *rl, int type, int rid)
3327 {
3328 	struct resource_list_entry *rle;
3329 
3330 	rle = resource_list_find(rl, type, rid);
3331 	if (rle != NULL && rle->flags & RLE_RESERVED)
3332 		return (1);
3333 	return (0);
3334 }
3335 
3336 /**
3337  * @brief Find a resource entry by type and rid.
3338  *
3339  * @param rl		the resource list to search
3340  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3341  * @param rid		the resource identifier
3342  *
3343  * @returns the resource entry pointer or NULL if there is no such
3344  * entry.
3345  */
3346 struct resource_list_entry *
3347 resource_list_find(struct resource_list *rl, int type, int rid)
3348 {
3349 	struct resource_list_entry *rle;
3350 
3351 	STAILQ_FOREACH(rle, rl, link) {
3352 		if (rle->type == type && rle->rid == rid)
3353 			return (rle);
3354 	}
3355 	return (NULL);
3356 }
3357 
3358 /**
3359  * @brief Delete a resource entry.
3360  *
3361  * @param rl		the resource list to edit
3362  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3363  * @param rid		the resource identifier
3364  */
3365 void
3366 resource_list_delete(struct resource_list *rl, int type, int rid)
3367 {
3368 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3369 
3370 	if (rle) {
3371 		if (rle->res != NULL)
3372 			panic("resource_list_delete: resource has not been released");
3373 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3374 		free(rle, M_BUS);
3375 	}
3376 }
3377 
3378 /**
3379  * @brief Allocate a reserved resource
3380  *
3381  * This can be used by buses to force the allocation of resources
3382  * that are always active in the system even if they are not allocated
3383  * by a driver (e.g. PCI BARs).  This function is usually called when
3384  * adding a new child to the bus.  The resource is allocated from the
3385  * parent bus when it is reserved.  The resource list entry is marked
3386  * with RLE_RESERVED to note that it is a reserved resource.
3387  *
3388  * Subsequent attempts to allocate the resource with
3389  * resource_list_alloc() will succeed the first time and will set
3390  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3391  * resource that has been allocated is released with
3392  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3393  * the actual resource remains allocated.  The resource can be released to
3394  * the parent bus by calling resource_list_unreserve().
3395  *
3396  * @param rl		the resource list to allocate from
3397  * @param bus		the parent device of @p child
3398  * @param child		the device for which the resource is being reserved
3399  * @param type		the type of resource to allocate
3400  * @param rid		a pointer to the resource identifier
3401  * @param start		hint at the start of the resource range - pass
3402  *			@c 0 for any start address
3403  * @param end		hint at the end of the resource range - pass
3404  *			@c ~0 for any end address
3405  * @param count		hint at the size of range required - pass @c 1
3406  *			for any size
3407  * @param flags		any extra flags to control the resource
3408  *			allocation - see @c RF_XXX flags in
3409  *			<sys/rman.h> for details
3410  *
3411  * @returns		the resource which was allocated or @c NULL if no
3412  *			resource could be allocated
3413  */
3414 struct resource *
3415 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3416     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3417 {
3418 	struct resource_list_entry *rle = NULL;
3419 	int passthrough = (device_get_parent(child) != bus);
3420 	struct resource *r;
3421 
3422 	if (passthrough)
3423 		panic(
3424     "resource_list_reserve() should only be called for direct children");
3425 	if (flags & RF_ACTIVE)
3426 		panic(
3427     "resource_list_reserve() should only reserve inactive resources");
3428 
3429 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3430 	    flags);
3431 	if (r != NULL) {
3432 		rle = resource_list_find(rl, type, *rid);
3433 		rle->flags |= RLE_RESERVED;
3434 	}
3435 	return (r);
3436 }
3437 
3438 /**
3439  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3440  *
3441  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3442  * and passing the allocation up to the parent of @p bus. This assumes
3443  * that the first entry of @c device_get_ivars(child) is a struct
3444  * resource_list. This also handles 'passthrough' allocations where a
3445  * child is a remote descendant of bus by passing the allocation up to
3446  * the parent of bus.
3447  *
3448  * Typically, a bus driver would store a list of child resources
3449  * somewhere in the child device's ivars (see device_get_ivars()) and
3450  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3451  * then call resource_list_alloc() to perform the allocation.
3452  *
3453  * @param rl		the resource list to allocate from
3454  * @param bus		the parent device of @p child
3455  * @param child		the device which is requesting an allocation
3456  * @param type		the type of resource to allocate
3457  * @param rid		a pointer to the resource identifier
3458  * @param start		hint at the start of the resource range - pass
3459  *			@c 0 for any start address
3460  * @param end		hint at the end of the resource range - pass
3461  *			@c ~0 for any end address
3462  * @param count		hint at the size of range required - pass @c 1
3463  *			for any size
3464  * @param flags		any extra flags to control the resource
3465  *			allocation - see @c RF_XXX flags in
3466  *			<sys/rman.h> for details
3467  *
3468  * @returns		the resource which was allocated or @c NULL if no
3469  *			resource could be allocated
3470  */
3471 struct resource *
3472 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3473     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3474 {
3475 	struct resource_list_entry *rle = NULL;
3476 	int passthrough = (device_get_parent(child) != bus);
3477 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3478 
3479 	if (passthrough) {
3480 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3481 		    type, rid, start, end, count, flags));
3482 	}
3483 
3484 	rle = resource_list_find(rl, type, *rid);
3485 
3486 	if (!rle)
3487 		return (NULL);		/* no resource of that type/rid */
3488 
3489 	if (rle->res) {
3490 		if (rle->flags & RLE_RESERVED) {
3491 			if (rle->flags & RLE_ALLOCATED)
3492 				return (NULL);
3493 			if ((flags & RF_ACTIVE) &&
3494 			    bus_activate_resource(child, type, *rid,
3495 			    rle->res) != 0)
3496 				return (NULL);
3497 			rle->flags |= RLE_ALLOCATED;
3498 			return (rle->res);
3499 		}
3500 		device_printf(bus,
3501 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3502 		    type, device_get_nameunit(child));
3503 		return (NULL);
3504 	}
3505 
3506 	if (isdefault) {
3507 		start = rle->start;
3508 		count = ulmax(count, rle->count);
3509 		end = ulmax(rle->end, start + count - 1);
3510 	}
3511 
3512 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3513 	    type, rid, start, end, count, flags);
3514 
3515 	/*
3516 	 * Record the new range.
3517 	 */
3518 	if (rle->res) {
3519 		rle->start = rman_get_start(rle->res);
3520 		rle->end = rman_get_end(rle->res);
3521 		rle->count = count;
3522 	}
3523 
3524 	return (rle->res);
3525 }
3526 
3527 /**
3528  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3529  *
3530  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3531  * used with resource_list_alloc().
3532  *
3533  * @param rl		the resource list which was allocated from
3534  * @param bus		the parent device of @p child
3535  * @param child		the device which is requesting a release
3536  * @param type		the type of resource to release
3537  * @param rid		the resource identifier
3538  * @param res		the resource to release
3539  *
3540  * @retval 0		success
3541  * @retval non-zero	a standard unix error code indicating what
3542  *			error condition prevented the operation
3543  */
3544 int
3545 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3546     int type, int rid, struct resource *res)
3547 {
3548 	struct resource_list_entry *rle = NULL;
3549 	int passthrough = (device_get_parent(child) != bus);
3550 	int error;
3551 
3552 	if (passthrough) {
3553 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3554 		    type, rid, res));
3555 	}
3556 
3557 	rle = resource_list_find(rl, type, rid);
3558 
3559 	if (!rle)
3560 		panic("resource_list_release: can't find resource");
3561 	if (!rle->res)
3562 		panic("resource_list_release: resource entry is not busy");
3563 	if (rle->flags & RLE_RESERVED) {
3564 		if (rle->flags & RLE_ALLOCATED) {
3565 			if (rman_get_flags(res) & RF_ACTIVE) {
3566 				error = bus_deactivate_resource(child, type,
3567 				    rid, res);
3568 				if (error)
3569 					return (error);
3570 			}
3571 			rle->flags &= ~RLE_ALLOCATED;
3572 			return (0);
3573 		}
3574 		return (EINVAL);
3575 	}
3576 
3577 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3578 	    type, rid, res);
3579 	if (error)
3580 		return (error);
3581 
3582 	rle->res = NULL;
3583 	return (0);
3584 }
3585 
3586 /**
3587  * @brief Release all active resources of a given type
3588  *
3589  * Release all active resources of a specified type.  This is intended
3590  * to be used to cleanup resources leaked by a driver after detach or
3591  * a failed attach.
3592  *
3593  * @param rl		the resource list which was allocated from
3594  * @param bus		the parent device of @p child
3595  * @param child		the device whose active resources are being released
3596  * @param type		the type of resources to release
3597  *
3598  * @retval 0		success
3599  * @retval EBUSY	at least one resource was active
3600  */
3601 int
3602 resource_list_release_active(struct resource_list *rl, device_t bus,
3603     device_t child, int type)
3604 {
3605 	struct resource_list_entry *rle;
3606 	int error, retval;
3607 
3608 	retval = 0;
3609 	STAILQ_FOREACH(rle, rl, link) {
3610 		if (rle->type != type)
3611 			continue;
3612 		if (rle->res == NULL)
3613 			continue;
3614 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3615 		    RLE_RESERVED)
3616 			continue;
3617 		retval = EBUSY;
3618 		error = resource_list_release(rl, bus, child, type,
3619 		    rman_get_rid(rle->res), rle->res);
3620 		if (error != 0)
3621 			device_printf(bus,
3622 			    "Failed to release active resource: %d\n", error);
3623 	}
3624 	return (retval);
3625 }
3626 
3627 /**
3628  * @brief Fully release a reserved resource
3629  *
3630  * Fully releases a resource reserved via resource_list_reserve().
3631  *
3632  * @param rl		the resource list which was allocated from
3633  * @param bus		the parent device of @p child
3634  * @param child		the device whose reserved resource is being released
3635  * @param type		the type of resource to release
3636  * @param rid		the resource identifier
3637  * @param res		the resource to release
3638  *
3639  * @retval 0		success
3640  * @retval non-zero	a standard unix error code indicating what
3641  *			error condition prevented the operation
3642  */
3643 int
3644 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3645     int type, int rid)
3646 {
3647 	struct resource_list_entry *rle = NULL;
3648 	int passthrough = (device_get_parent(child) != bus);
3649 
3650 	if (passthrough)
3651 		panic(
3652     "resource_list_unreserve() should only be called for direct children");
3653 
3654 	rle = resource_list_find(rl, type, rid);
3655 
3656 	if (!rle)
3657 		panic("resource_list_unreserve: can't find resource");
3658 	if (!(rle->flags & RLE_RESERVED))
3659 		return (EINVAL);
3660 	if (rle->flags & RLE_ALLOCATED)
3661 		return (EBUSY);
3662 	rle->flags &= ~RLE_RESERVED;
3663 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3664 }
3665 
3666 /**
3667  * @brief Print a description of resources in a resource list
3668  *
3669  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3670  * The name is printed if at least one resource of the given type is available.
3671  * The format is used to print resource start and end.
3672  *
3673  * @param rl		the resource list to print
3674  * @param name		the name of @p type, e.g. @c "memory"
3675  * @param type		type type of resource entry to print
3676  * @param format	printf(9) format string to print resource
3677  *			start and end values
3678  *
3679  * @returns		the number of characters printed
3680  */
3681 int
3682 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3683     const char *format)
3684 {
3685 	struct resource_list_entry *rle;
3686 	int printed, retval;
3687 
3688 	printed = 0;
3689 	retval = 0;
3690 	/* Yes, this is kinda cheating */
3691 	STAILQ_FOREACH(rle, rl, link) {
3692 		if (rle->type == type) {
3693 			if (printed == 0)
3694 				retval += printf(" %s ", name);
3695 			else
3696 				retval += printf(",");
3697 			printed++;
3698 			retval += printf(format, rle->start);
3699 			if (rle->count > 1) {
3700 				retval += printf("-");
3701 				retval += printf(format, rle->start +
3702 						 rle->count - 1);
3703 			}
3704 		}
3705 	}
3706 	return (retval);
3707 }
3708 
3709 /**
3710  * @brief Releases all the resources in a list.
3711  *
3712  * @param rl		The resource list to purge.
3713  *
3714  * @returns		nothing
3715  */
3716 void
3717 resource_list_purge(struct resource_list *rl)
3718 {
3719 	struct resource_list_entry *rle;
3720 
3721 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3722 		if (rle->res)
3723 			bus_release_resource(rman_get_device(rle->res),
3724 			    rle->type, rle->rid, rle->res);
3725 		STAILQ_REMOVE_HEAD(rl, link);
3726 		free(rle, M_BUS);
3727 	}
3728 }
3729 
3730 device_t
3731 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3732 {
3733 	return (device_add_child_ordered(dev, order, name, unit));
3734 }
3735 
3736 /**
3737  * @brief Helper function for implementing DEVICE_PROBE()
3738  *
3739  * This function can be used to help implement the DEVICE_PROBE() for
3740  * a bus (i.e. a device which has other devices attached to it). It
3741  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3742  * devclass.
3743  */
3744 int
3745 bus_generic_probe(device_t dev)
3746 {
3747 	devclass_t dc = dev->devclass;
3748 	driverlink_t dl;
3749 
3750 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3751 		/*
3752 		 * If this driver's pass is too high, then ignore it.
3753 		 * For most drivers in the default pass, this will
3754 		 * never be true.  For early-pass drivers they will
3755 		 * only call the identify routines of eligible drivers
3756 		 * when this routine is called.  Drivers for later
3757 		 * passes should have their identify routines called
3758 		 * on early-pass buses during BUS_NEW_PASS().
3759 		 */
3760 		if (dl->pass > bus_current_pass)
3761 			continue;
3762 		DEVICE_IDENTIFY(dl->driver, dev);
3763 	}
3764 
3765 	return (0);
3766 }
3767 
3768 /**
3769  * @brief Helper function for implementing DEVICE_ATTACH()
3770  *
3771  * This function can be used to help implement the DEVICE_ATTACH() for
3772  * a bus. It calls device_probe_and_attach() for each of the device's
3773  * children.
3774  */
3775 int
3776 bus_generic_attach(device_t dev)
3777 {
3778 	device_t child;
3779 
3780 	TAILQ_FOREACH(child, &dev->children, link) {
3781 		device_probe_and_attach(child);
3782 	}
3783 
3784 	return (0);
3785 }
3786 
3787 /**
3788  * @brief Helper function for delaying attaching children
3789  *
3790  * Many buses can't run transactions on the bus which children need to probe and
3791  * attach until after interrupts and/or timers are running.  This function
3792  * delays their attach until interrupts and timers are enabled.
3793  */
3794 int
3795 bus_delayed_attach_children(device_t dev)
3796 {
3797 	/* Probe and attach the bus children when interrupts are available */
3798 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3799 
3800 	return (0);
3801 }
3802 
3803 /**
3804  * @brief Helper function for implementing DEVICE_DETACH()
3805  *
3806  * This function can be used to help implement the DEVICE_DETACH() for
3807  * a bus. It calls device_detach() for each of the device's
3808  * children.
3809  */
3810 int
3811 bus_generic_detach(device_t dev)
3812 {
3813 	device_t child;
3814 	int error;
3815 
3816 	if (dev->state != DS_ATTACHED)
3817 		return (EBUSY);
3818 
3819 	/*
3820 	 * Detach children in the reverse order.
3821 	 * See bus_generic_suspend for details.
3822 	 */
3823 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3824 		if ((error = device_detach(child)) != 0)
3825 			return (error);
3826 	}
3827 
3828 	return (0);
3829 }
3830 
3831 /**
3832  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3833  *
3834  * This function can be used to help implement the DEVICE_SHUTDOWN()
3835  * for a bus. It calls device_shutdown() for each of the device's
3836  * children.
3837  */
3838 int
3839 bus_generic_shutdown(device_t dev)
3840 {
3841 	device_t child;
3842 
3843 	/*
3844 	 * Shut down children in the reverse order.
3845 	 * See bus_generic_suspend for details.
3846 	 */
3847 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3848 		device_shutdown(child);
3849 	}
3850 
3851 	return (0);
3852 }
3853 
3854 /**
3855  * @brief Default function for suspending a child device.
3856  *
3857  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3858  */
3859 int
3860 bus_generic_suspend_child(device_t dev, device_t child)
3861 {
3862 	int	error;
3863 
3864 	error = DEVICE_SUSPEND(child);
3865 
3866 	if (error == 0)
3867 		child->flags |= DF_SUSPENDED;
3868 
3869 	return (error);
3870 }
3871 
3872 /**
3873  * @brief Default function for resuming a child device.
3874  *
3875  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3876  */
3877 int
3878 bus_generic_resume_child(device_t dev, device_t child)
3879 {
3880 	DEVICE_RESUME(child);
3881 	child->flags &= ~DF_SUSPENDED;
3882 
3883 	return (0);
3884 }
3885 
3886 /**
3887  * @brief Helper function for implementing DEVICE_SUSPEND()
3888  *
3889  * This function can be used to help implement the DEVICE_SUSPEND()
3890  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3891  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3892  * operation is aborted and any devices which were suspended are
3893  * resumed immediately by calling their DEVICE_RESUME() methods.
3894  */
3895 int
3896 bus_generic_suspend(device_t dev)
3897 {
3898 	int		error;
3899 	device_t	child;
3900 
3901 	/*
3902 	 * Suspend children in the reverse order.
3903 	 * For most buses all children are equal, so the order does not matter.
3904 	 * Other buses, such as acpi, carefully order their child devices to
3905 	 * express implicit dependencies between them.  For such buses it is
3906 	 * safer to bring down devices in the reverse order.
3907 	 */
3908 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3909 		error = BUS_SUSPEND_CHILD(dev, child);
3910 		if (error != 0) {
3911 			child = TAILQ_NEXT(child, link);
3912 			if (child != NULL) {
3913 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3914 					BUS_RESUME_CHILD(dev, child);
3915 			}
3916 			return (error);
3917 		}
3918 	}
3919 	return (0);
3920 }
3921 
3922 /**
3923  * @brief Helper function for implementing DEVICE_RESUME()
3924  *
3925  * This function can be used to help implement the DEVICE_RESUME() for
3926  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3927  */
3928 int
3929 bus_generic_resume(device_t dev)
3930 {
3931 	device_t	child;
3932 
3933 	TAILQ_FOREACH(child, &dev->children, link) {
3934 		BUS_RESUME_CHILD(dev, child);
3935 		/* if resume fails, there's nothing we can usefully do... */
3936 	}
3937 	return (0);
3938 }
3939 
3940 /**
3941  * @brief Helper function for implementing BUS_RESET_POST
3942  *
3943  * Bus can use this function to implement common operations of
3944  * re-attaching or resuming the children after the bus itself was
3945  * reset, and after restoring bus-unique state of children.
3946  *
3947  * @param dev	The bus
3948  * #param flags	DEVF_RESET_*
3949  */
3950 int
3951 bus_helper_reset_post(device_t dev, int flags)
3952 {
3953 	device_t child;
3954 	int error, error1;
3955 
3956 	error = 0;
3957 	TAILQ_FOREACH(child, &dev->children,link) {
3958 		BUS_RESET_POST(dev, child);
3959 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3960 		    device_probe_and_attach(child) :
3961 		    BUS_RESUME_CHILD(dev, child);
3962 		if (error == 0 && error1 != 0)
3963 			error = error1;
3964 	}
3965 	return (error);
3966 }
3967 
3968 static void
3969 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3970 {
3971 	child = TAILQ_NEXT(child, link);
3972 	if (child == NULL)
3973 		return;
3974 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3975 		BUS_RESET_POST(dev, child);
3976 		if ((flags & DEVF_RESET_DETACH) != 0)
3977 			device_probe_and_attach(child);
3978 		else
3979 			BUS_RESUME_CHILD(dev, child);
3980 	}
3981 }
3982 
3983 /**
3984  * @brief Helper function for implementing BUS_RESET_PREPARE
3985  *
3986  * Bus can use this function to implement common operations of
3987  * detaching or suspending the children before the bus itself is
3988  * reset, and then save bus-unique state of children that must
3989  * persists around reset.
3990  *
3991  * @param dev	The bus
3992  * #param flags	DEVF_RESET_*
3993  */
3994 int
3995 bus_helper_reset_prepare(device_t dev, int flags)
3996 {
3997 	device_t child;
3998 	int error;
3999 
4000 	if (dev->state != DS_ATTACHED)
4001 		return (EBUSY);
4002 
4003 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
4004 		if ((flags & DEVF_RESET_DETACH) != 0) {
4005 			error = device_get_state(child) == DS_ATTACHED ?
4006 			    device_detach(child) : 0;
4007 		} else {
4008 			error = BUS_SUSPEND_CHILD(dev, child);
4009 		}
4010 		if (error == 0) {
4011 			error = BUS_RESET_PREPARE(dev, child);
4012 			if (error != 0) {
4013 				if ((flags & DEVF_RESET_DETACH) != 0)
4014 					device_probe_and_attach(child);
4015 				else
4016 					BUS_RESUME_CHILD(dev, child);
4017 			}
4018 		}
4019 		if (error != 0) {
4020 			bus_helper_reset_prepare_rollback(dev, child, flags);
4021 			return (error);
4022 		}
4023 	}
4024 	return (0);
4025 }
4026 
4027 /**
4028  * @brief Helper function for implementing BUS_PRINT_CHILD().
4029  *
4030  * This function prints the first part of the ascii representation of
4031  * @p child, including its name, unit and description (if any - see
4032  * device_set_desc()).
4033  *
4034  * @returns the number of characters printed
4035  */
4036 int
4037 bus_print_child_header(device_t dev, device_t child)
4038 {
4039 	int	retval = 0;
4040 
4041 	if (device_get_desc(child)) {
4042 		retval += device_printf(child, "<%s>", device_get_desc(child));
4043 	} else {
4044 		retval += printf("%s", device_get_nameunit(child));
4045 	}
4046 
4047 	return (retval);
4048 }
4049 
4050 /**
4051  * @brief Helper function for implementing BUS_PRINT_CHILD().
4052  *
4053  * This function prints the last part of the ascii representation of
4054  * @p child, which consists of the string @c " on " followed by the
4055  * name and unit of the @p dev.
4056  *
4057  * @returns the number of characters printed
4058  */
4059 int
4060 bus_print_child_footer(device_t dev, device_t child)
4061 {
4062 	return (printf(" on %s\n", device_get_nameunit(dev)));
4063 }
4064 
4065 /**
4066  * @brief Helper function for implementing BUS_PRINT_CHILD().
4067  *
4068  * This function prints out the VM domain for the given device.
4069  *
4070  * @returns the number of characters printed
4071  */
4072 int
4073 bus_print_child_domain(device_t dev, device_t child)
4074 {
4075 	int domain;
4076 
4077 	/* No domain? Don't print anything */
4078 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4079 		return (0);
4080 
4081 	return (printf(" numa-domain %d", domain));
4082 }
4083 
4084 /**
4085  * @brief Helper function for implementing BUS_PRINT_CHILD().
4086  *
4087  * This function simply calls bus_print_child_header() followed by
4088  * bus_print_child_footer().
4089  *
4090  * @returns the number of characters printed
4091  */
4092 int
4093 bus_generic_print_child(device_t dev, device_t child)
4094 {
4095 	int	retval = 0;
4096 
4097 	retval += bus_print_child_header(dev, child);
4098 	retval += bus_print_child_domain(dev, child);
4099 	retval += bus_print_child_footer(dev, child);
4100 
4101 	return (retval);
4102 }
4103 
4104 /**
4105  * @brief Stub function for implementing BUS_READ_IVAR().
4106  *
4107  * @returns ENOENT
4108  */
4109 int
4110 bus_generic_read_ivar(device_t dev, device_t child, int index,
4111     uintptr_t * result)
4112 {
4113 	return (ENOENT);
4114 }
4115 
4116 /**
4117  * @brief Stub function for implementing BUS_WRITE_IVAR().
4118  *
4119  * @returns ENOENT
4120  */
4121 int
4122 bus_generic_write_ivar(device_t dev, device_t child, int index,
4123     uintptr_t value)
4124 {
4125 	return (ENOENT);
4126 }
4127 
4128 /**
4129  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4130  *
4131  * @returns NULL
4132  */
4133 struct resource_list *
4134 bus_generic_get_resource_list(device_t dev, device_t child)
4135 {
4136 	return (NULL);
4137 }
4138 
4139 /**
4140  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4141  *
4142  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4143  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4144  * and then calls device_probe_and_attach() for each unattached child.
4145  */
4146 void
4147 bus_generic_driver_added(device_t dev, driver_t *driver)
4148 {
4149 	device_t child;
4150 
4151 	DEVICE_IDENTIFY(driver, dev);
4152 	TAILQ_FOREACH(child, &dev->children, link) {
4153 		if (child->state == DS_NOTPRESENT)
4154 			device_probe_and_attach(child);
4155 	}
4156 }
4157 
4158 /**
4159  * @brief Helper function for implementing BUS_NEW_PASS().
4160  *
4161  * This implementing of BUS_NEW_PASS() first calls the identify
4162  * routines for any drivers that probe at the current pass.  Then it
4163  * walks the list of devices for this bus.  If a device is already
4164  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4165  * device is not already attached, it attempts to attach a driver to
4166  * it.
4167  */
4168 void
4169 bus_generic_new_pass(device_t dev)
4170 {
4171 	driverlink_t dl;
4172 	devclass_t dc;
4173 	device_t child;
4174 
4175 	dc = dev->devclass;
4176 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4177 		if (dl->pass == bus_current_pass)
4178 			DEVICE_IDENTIFY(dl->driver, dev);
4179 	}
4180 	TAILQ_FOREACH(child, &dev->children, link) {
4181 		if (child->state >= DS_ATTACHED)
4182 			BUS_NEW_PASS(child);
4183 		else if (child->state == DS_NOTPRESENT)
4184 			device_probe_and_attach(child);
4185 	}
4186 }
4187 
4188 /**
4189  * @brief Helper function for implementing BUS_SETUP_INTR().
4190  *
4191  * This simple implementation of BUS_SETUP_INTR() simply calls the
4192  * BUS_SETUP_INTR() method of the parent of @p dev.
4193  */
4194 int
4195 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4196     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4197     void **cookiep)
4198 {
4199 	/* Propagate up the bus hierarchy until someone handles it. */
4200 	if (dev->parent)
4201 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4202 		    filter, intr, arg, cookiep));
4203 	return (EINVAL);
4204 }
4205 
4206 /**
4207  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4208  *
4209  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4210  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4211  */
4212 int
4213 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4214     void *cookie)
4215 {
4216 	/* Propagate up the bus hierarchy until someone handles it. */
4217 	if (dev->parent)
4218 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4219 	return (EINVAL);
4220 }
4221 
4222 /**
4223  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4224  *
4225  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4226  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4227  */
4228 int
4229 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4230 {
4231 	/* Propagate up the bus hierarchy until someone handles it. */
4232 	if (dev->parent)
4233 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4234 	return (EINVAL);
4235 }
4236 
4237 /**
4238  * @brief Helper function for implementing BUS_RESUME_INTR().
4239  *
4240  * This simple implementation of BUS_RESUME_INTR() simply calls the
4241  * BUS_RESUME_INTR() method of the parent of @p dev.
4242  */
4243 int
4244 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4245 {
4246 	/* Propagate up the bus hierarchy until someone handles it. */
4247 	if (dev->parent)
4248 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4249 	return (EINVAL);
4250 }
4251 
4252 /**
4253  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4254  *
4255  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4256  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4257  */
4258 int
4259 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4260     struct resource *r, rman_res_t start, rman_res_t end)
4261 {
4262 	/* Propagate up the bus hierarchy until someone handles it. */
4263 	if (dev->parent)
4264 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4265 		    end));
4266 	return (EINVAL);
4267 }
4268 
4269 /*
4270  * @brief Helper function for implementing BUS_TRANSLATE_RESOURCE().
4271  *
4272  * This simple implementation of BUS_TRANSLATE_RESOURCE() simply calls the
4273  * BUS_TRANSLATE_RESOURCE() method of the parent of @p dev.  If there is no
4274  * parent, no translation happens.
4275  */
4276 int
4277 bus_generic_translate_resource(device_t dev, int type, rman_res_t start,
4278     rman_res_t *newstart)
4279 {
4280 	if (dev->parent)
4281 		return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start,
4282 		    newstart));
4283 	*newstart = start;
4284 	return (0);
4285 }
4286 
4287 /**
4288  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4289  *
4290  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4291  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4292  */
4293 struct resource *
4294 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4295     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4296 {
4297 	/* Propagate up the bus hierarchy until someone handles it. */
4298 	if (dev->parent)
4299 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4300 		    start, end, count, flags));
4301 	return (NULL);
4302 }
4303 
4304 /**
4305  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4306  *
4307  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4308  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4309  */
4310 int
4311 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4312     struct resource *r)
4313 {
4314 	/* Propagate up the bus hierarchy until someone handles it. */
4315 	if (dev->parent)
4316 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4317 		    r));
4318 	return (EINVAL);
4319 }
4320 
4321 /**
4322  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4323  *
4324  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4325  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4326  */
4327 int
4328 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4329     struct resource *r)
4330 {
4331 	/* Propagate up the bus hierarchy until someone handles it. */
4332 	if (dev->parent)
4333 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4334 		    r));
4335 	return (EINVAL);
4336 }
4337 
4338 /**
4339  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4340  *
4341  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4342  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4343  */
4344 int
4345 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4346     int rid, struct resource *r)
4347 {
4348 	/* Propagate up the bus hierarchy until someone handles it. */
4349 	if (dev->parent)
4350 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4351 		    r));
4352 	return (EINVAL);
4353 }
4354 
4355 /**
4356  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4357  *
4358  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4359  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4360  */
4361 int
4362 bus_generic_map_resource(device_t dev, device_t child, int type,
4363     struct resource *r, struct resource_map_request *args,
4364     struct resource_map *map)
4365 {
4366 	/* Propagate up the bus hierarchy until someone handles it. */
4367 	if (dev->parent)
4368 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4369 		    map));
4370 	return (EINVAL);
4371 }
4372 
4373 /**
4374  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4375  *
4376  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4377  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4378  */
4379 int
4380 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4381     struct resource *r, struct resource_map *map)
4382 {
4383 	/* Propagate up the bus hierarchy until someone handles it. */
4384 	if (dev->parent)
4385 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4386 	return (EINVAL);
4387 }
4388 
4389 /**
4390  * @brief Helper function for implementing BUS_BIND_INTR().
4391  *
4392  * This simple implementation of BUS_BIND_INTR() simply calls the
4393  * BUS_BIND_INTR() method of the parent of @p dev.
4394  */
4395 int
4396 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4397     int cpu)
4398 {
4399 	/* Propagate up the bus hierarchy until someone handles it. */
4400 	if (dev->parent)
4401 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4402 	return (EINVAL);
4403 }
4404 
4405 /**
4406  * @brief Helper function for implementing BUS_CONFIG_INTR().
4407  *
4408  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4409  * BUS_CONFIG_INTR() method of the parent of @p dev.
4410  */
4411 int
4412 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4413     enum intr_polarity pol)
4414 {
4415 	/* Propagate up the bus hierarchy until someone handles it. */
4416 	if (dev->parent)
4417 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4418 	return (EINVAL);
4419 }
4420 
4421 /**
4422  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4423  *
4424  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4425  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4426  */
4427 int
4428 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4429     void *cookie, const char *descr)
4430 {
4431 	/* Propagate up the bus hierarchy until someone handles it. */
4432 	if (dev->parent)
4433 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4434 		    descr));
4435 	return (EINVAL);
4436 }
4437 
4438 /**
4439  * @brief Helper function for implementing BUS_GET_CPUS().
4440  *
4441  * This simple implementation of BUS_GET_CPUS() simply calls the
4442  * BUS_GET_CPUS() method of the parent of @p dev.
4443  */
4444 int
4445 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4446     size_t setsize, cpuset_t *cpuset)
4447 {
4448 	/* Propagate up the bus hierarchy until someone handles it. */
4449 	if (dev->parent != NULL)
4450 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4451 	return (EINVAL);
4452 }
4453 
4454 /**
4455  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4456  *
4457  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4458  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4459  */
4460 bus_dma_tag_t
4461 bus_generic_get_dma_tag(device_t dev, device_t child)
4462 {
4463 	/* Propagate up the bus hierarchy until someone handles it. */
4464 	if (dev->parent != NULL)
4465 		return (BUS_GET_DMA_TAG(dev->parent, child));
4466 	return (NULL);
4467 }
4468 
4469 /**
4470  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4471  *
4472  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4473  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4474  */
4475 bus_space_tag_t
4476 bus_generic_get_bus_tag(device_t dev, device_t child)
4477 {
4478 	/* Propagate up the bus hierarchy until someone handles it. */
4479 	if (dev->parent != NULL)
4480 		return (BUS_GET_BUS_TAG(dev->parent, child));
4481 	return ((bus_space_tag_t)0);
4482 }
4483 
4484 /**
4485  * @brief Helper function for implementing BUS_GET_RESOURCE().
4486  *
4487  * This implementation of BUS_GET_RESOURCE() uses the
4488  * resource_list_find() function to do most of the work. It calls
4489  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4490  * search.
4491  */
4492 int
4493 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4494     rman_res_t *startp, rman_res_t *countp)
4495 {
4496 	struct resource_list *		rl = NULL;
4497 	struct resource_list_entry *	rle = NULL;
4498 
4499 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4500 	if (!rl)
4501 		return (EINVAL);
4502 
4503 	rle = resource_list_find(rl, type, rid);
4504 	if (!rle)
4505 		return (ENOENT);
4506 
4507 	if (startp)
4508 		*startp = rle->start;
4509 	if (countp)
4510 		*countp = rle->count;
4511 
4512 	return (0);
4513 }
4514 
4515 /**
4516  * @brief Helper function for implementing BUS_SET_RESOURCE().
4517  *
4518  * This implementation of BUS_SET_RESOURCE() uses the
4519  * resource_list_add() function to do most of the work. It calls
4520  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4521  * edit.
4522  */
4523 int
4524 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4525     rman_res_t start, rman_res_t count)
4526 {
4527 	struct resource_list *		rl = NULL;
4528 
4529 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4530 	if (!rl)
4531 		return (EINVAL);
4532 
4533 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4534 
4535 	return (0);
4536 }
4537 
4538 /**
4539  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4540  *
4541  * This implementation of BUS_DELETE_RESOURCE() uses the
4542  * resource_list_delete() function to do most of the work. It calls
4543  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4544  * edit.
4545  */
4546 void
4547 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4548 {
4549 	struct resource_list *		rl = NULL;
4550 
4551 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4552 	if (!rl)
4553 		return;
4554 
4555 	resource_list_delete(rl, type, rid);
4556 
4557 	return;
4558 }
4559 
4560 /**
4561  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4562  *
4563  * This implementation of BUS_RELEASE_RESOURCE() uses the
4564  * resource_list_release() function to do most of the work. It calls
4565  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4566  */
4567 int
4568 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4569     int rid, struct resource *r)
4570 {
4571 	struct resource_list *		rl = NULL;
4572 
4573 	if (device_get_parent(child) != dev)
4574 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4575 		    type, rid, r));
4576 
4577 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4578 	if (!rl)
4579 		return (EINVAL);
4580 
4581 	return (resource_list_release(rl, dev, child, type, rid, r));
4582 }
4583 
4584 /**
4585  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4586  *
4587  * This implementation of BUS_ALLOC_RESOURCE() uses the
4588  * resource_list_alloc() function to do most of the work. It calls
4589  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4590  */
4591 struct resource *
4592 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4593     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4594 {
4595 	struct resource_list *		rl = NULL;
4596 
4597 	if (device_get_parent(child) != dev)
4598 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4599 		    type, rid, start, end, count, flags));
4600 
4601 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4602 	if (!rl)
4603 		return (NULL);
4604 
4605 	return (resource_list_alloc(rl, dev, child, type, rid,
4606 	    start, end, count, flags));
4607 }
4608 
4609 /**
4610  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4611  *
4612  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4613  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4614  */
4615 int
4616 bus_generic_child_present(device_t dev, device_t child)
4617 {
4618 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4619 }
4620 
4621 int
4622 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4623 {
4624 	if (dev->parent)
4625 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4626 
4627 	return (ENOENT);
4628 }
4629 
4630 /**
4631  * @brief Helper function for implementing BUS_RESCAN().
4632  *
4633  * This null implementation of BUS_RESCAN() always fails to indicate
4634  * the bus does not support rescanning.
4635  */
4636 int
4637 bus_null_rescan(device_t dev)
4638 {
4639 	return (ENXIO);
4640 }
4641 
4642 /*
4643  * Some convenience functions to make it easier for drivers to use the
4644  * resource-management functions.  All these really do is hide the
4645  * indirection through the parent's method table, making for slightly
4646  * less-wordy code.  In the future, it might make sense for this code
4647  * to maintain some sort of a list of resources allocated by each device.
4648  */
4649 
4650 int
4651 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4652     struct resource **res)
4653 {
4654 	int i;
4655 
4656 	for (i = 0; rs[i].type != -1; i++)
4657 		res[i] = NULL;
4658 	for (i = 0; rs[i].type != -1; i++) {
4659 		res[i] = bus_alloc_resource_any(dev,
4660 		    rs[i].type, &rs[i].rid, rs[i].flags);
4661 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4662 			bus_release_resources(dev, rs, res);
4663 			return (ENXIO);
4664 		}
4665 	}
4666 	return (0);
4667 }
4668 
4669 void
4670 bus_release_resources(device_t dev, const struct resource_spec *rs,
4671     struct resource **res)
4672 {
4673 	int i;
4674 
4675 	for (i = 0; rs[i].type != -1; i++)
4676 		if (res[i] != NULL) {
4677 			bus_release_resource(
4678 			    dev, rs[i].type, rs[i].rid, res[i]);
4679 			res[i] = NULL;
4680 		}
4681 }
4682 
4683 /**
4684  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4685  *
4686  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4687  * parent of @p dev.
4688  */
4689 struct resource *
4690 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4691     rman_res_t end, rman_res_t count, u_int flags)
4692 {
4693 	struct resource *res;
4694 
4695 	if (dev->parent == NULL)
4696 		return (NULL);
4697 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4698 	    count, flags);
4699 	return (res);
4700 }
4701 
4702 /**
4703  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4704  *
4705  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4706  * parent of @p dev.
4707  */
4708 int
4709 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4710     rman_res_t end)
4711 {
4712 	if (dev->parent == NULL)
4713 		return (EINVAL);
4714 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4715 }
4716 
4717 /**
4718  * @brief Wrapper function for BUS_TRANSLATE_RESOURCE().
4719  *
4720  * This function simply calls the BUS_TRANSLATE_RESOURCE() method of the
4721  * parent of @p dev.
4722  */
4723 int
4724 bus_translate_resource(device_t dev, int type, rman_res_t start,
4725     rman_res_t *newstart)
4726 {
4727 	if (dev->parent == NULL)
4728 		return (EINVAL);
4729 	return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start, newstart));
4730 }
4731 
4732 /**
4733  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4734  *
4735  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4736  * parent of @p dev.
4737  */
4738 int
4739 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4740 {
4741 	if (dev->parent == NULL)
4742 		return (EINVAL);
4743 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4744 }
4745 
4746 /**
4747  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4748  *
4749  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4750  * parent of @p dev.
4751  */
4752 int
4753 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4754 {
4755 	if (dev->parent == NULL)
4756 		return (EINVAL);
4757 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4758 }
4759 
4760 /**
4761  * @brief Wrapper function for BUS_MAP_RESOURCE().
4762  *
4763  * This function simply calls the BUS_MAP_RESOURCE() method of the
4764  * parent of @p dev.
4765  */
4766 int
4767 bus_map_resource(device_t dev, int type, struct resource *r,
4768     struct resource_map_request *args, struct resource_map *map)
4769 {
4770 	if (dev->parent == NULL)
4771 		return (EINVAL);
4772 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4773 }
4774 
4775 /**
4776  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4777  *
4778  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4779  * parent of @p dev.
4780  */
4781 int
4782 bus_unmap_resource(device_t dev, int type, struct resource *r,
4783     struct resource_map *map)
4784 {
4785 	if (dev->parent == NULL)
4786 		return (EINVAL);
4787 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4788 }
4789 
4790 /**
4791  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4792  *
4793  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4794  * parent of @p dev.
4795  */
4796 int
4797 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4798 {
4799 	int rv;
4800 
4801 	if (dev->parent == NULL)
4802 		return (EINVAL);
4803 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4804 	return (rv);
4805 }
4806 
4807 /**
4808  * @brief Wrapper function for BUS_SETUP_INTR().
4809  *
4810  * This function simply calls the BUS_SETUP_INTR() method of the
4811  * parent of @p dev.
4812  */
4813 int
4814 bus_setup_intr(device_t dev, struct resource *r, int flags,
4815     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4816 {
4817 	int error;
4818 
4819 	if (dev->parent == NULL)
4820 		return (EINVAL);
4821 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4822 	    arg, cookiep);
4823 	if (error != 0)
4824 		return (error);
4825 	if (handler != NULL && !(flags & INTR_MPSAFE))
4826 		device_printf(dev, "[GIANT-LOCKED]\n");
4827 	return (0);
4828 }
4829 
4830 /**
4831  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4832  *
4833  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4834  * parent of @p dev.
4835  */
4836 int
4837 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4838 {
4839 	if (dev->parent == NULL)
4840 		return (EINVAL);
4841 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4842 }
4843 
4844 /**
4845  * @brief Wrapper function for BUS_SUSPEND_INTR().
4846  *
4847  * This function simply calls the BUS_SUSPEND_INTR() method of the
4848  * parent of @p dev.
4849  */
4850 int
4851 bus_suspend_intr(device_t dev, struct resource *r)
4852 {
4853 	if (dev->parent == NULL)
4854 		return (EINVAL);
4855 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4856 }
4857 
4858 /**
4859  * @brief Wrapper function for BUS_RESUME_INTR().
4860  *
4861  * This function simply calls the BUS_RESUME_INTR() method of the
4862  * parent of @p dev.
4863  */
4864 int
4865 bus_resume_intr(device_t dev, struct resource *r)
4866 {
4867 	if (dev->parent == NULL)
4868 		return (EINVAL);
4869 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4870 }
4871 
4872 /**
4873  * @brief Wrapper function for BUS_BIND_INTR().
4874  *
4875  * This function simply calls the BUS_BIND_INTR() method of the
4876  * parent of @p dev.
4877  */
4878 int
4879 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4880 {
4881 	if (dev->parent == NULL)
4882 		return (EINVAL);
4883 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4884 }
4885 
4886 /**
4887  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4888  *
4889  * This function first formats the requested description into a
4890  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4891  * the parent of @p dev.
4892  */
4893 int
4894 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4895     const char *fmt, ...)
4896 {
4897 	va_list ap;
4898 	char descr[MAXCOMLEN + 1];
4899 
4900 	if (dev->parent == NULL)
4901 		return (EINVAL);
4902 	va_start(ap, fmt);
4903 	vsnprintf(descr, sizeof(descr), fmt, ap);
4904 	va_end(ap);
4905 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4906 }
4907 
4908 /**
4909  * @brief Wrapper function for BUS_SET_RESOURCE().
4910  *
4911  * This function simply calls the BUS_SET_RESOURCE() method of the
4912  * parent of @p dev.
4913  */
4914 int
4915 bus_set_resource(device_t dev, int type, int rid,
4916     rman_res_t start, rman_res_t count)
4917 {
4918 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4919 	    start, count));
4920 }
4921 
4922 /**
4923  * @brief Wrapper function for BUS_GET_RESOURCE().
4924  *
4925  * This function simply calls the BUS_GET_RESOURCE() method of the
4926  * parent of @p dev.
4927  */
4928 int
4929 bus_get_resource(device_t dev, int type, int rid,
4930     rman_res_t *startp, rman_res_t *countp)
4931 {
4932 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4933 	    startp, countp));
4934 }
4935 
4936 /**
4937  * @brief Wrapper function for BUS_GET_RESOURCE().
4938  *
4939  * This function simply calls the BUS_GET_RESOURCE() method of the
4940  * parent of @p dev and returns the start value.
4941  */
4942 rman_res_t
4943 bus_get_resource_start(device_t dev, int type, int rid)
4944 {
4945 	rman_res_t start;
4946 	rman_res_t count;
4947 	int error;
4948 
4949 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4950 	    &start, &count);
4951 	if (error)
4952 		return (0);
4953 	return (start);
4954 }
4955 
4956 /**
4957  * @brief Wrapper function for BUS_GET_RESOURCE().
4958  *
4959  * This function simply calls the BUS_GET_RESOURCE() method of the
4960  * parent of @p dev and returns the count value.
4961  */
4962 rman_res_t
4963 bus_get_resource_count(device_t dev, int type, int rid)
4964 {
4965 	rman_res_t start;
4966 	rman_res_t count;
4967 	int error;
4968 
4969 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4970 	    &start, &count);
4971 	if (error)
4972 		return (0);
4973 	return (count);
4974 }
4975 
4976 /**
4977  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4978  *
4979  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4980  * parent of @p dev.
4981  */
4982 void
4983 bus_delete_resource(device_t dev, int type, int rid)
4984 {
4985 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4986 }
4987 
4988 /**
4989  * @brief Wrapper function for BUS_CHILD_PRESENT().
4990  *
4991  * This function simply calls the BUS_CHILD_PRESENT() method of the
4992  * parent of @p dev.
4993  */
4994 int
4995 bus_child_present(device_t child)
4996 {
4997 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4998 }
4999 
5000 /**
5001  * @brief Wrapper function for BUS_CHILD_PNPINFO().
5002  *
5003  * This function simply calls the BUS_CHILD_PNPINFO() method of the parent of @p
5004  * dev.
5005  */
5006 int
5007 bus_child_pnpinfo(device_t child, struct sbuf *sb)
5008 {
5009 	device_t parent;
5010 
5011 	parent = device_get_parent(child);
5012 	if (parent == NULL)
5013 		return (0);
5014 	return (BUS_CHILD_PNPINFO(parent, child, sb));
5015 }
5016 
5017 /**
5018  * @brief Generic implementation that does nothing for bus_child_pnpinfo
5019  *
5020  * This function has the right signature and returns 0 since the sbuf is passed
5021  * to us to append to.
5022  */
5023 int
5024 bus_generic_child_pnpinfo(device_t dev, device_t child, struct sbuf *sb)
5025 {
5026 	return (0);
5027 }
5028 
5029 /**
5030  * @brief Wrapper function for BUS_CHILD_LOCATION().
5031  *
5032  * This function simply calls the BUS_CHILD_LOCATION() method of the parent of
5033  * @p dev.
5034  */
5035 int
5036 bus_child_location(device_t child, struct sbuf *sb)
5037 {
5038 	device_t parent;
5039 
5040 	parent = device_get_parent(child);
5041 	if (parent == NULL)
5042 		return (0);
5043 	return (BUS_CHILD_LOCATION(parent, child, sb));
5044 }
5045 
5046 /**
5047  * @brief Generic implementation that does nothing for bus_child_location
5048  *
5049  * This function has the right signature and returns 0 since the sbuf is passed
5050  * to us to append to.
5051  */
5052 int
5053 bus_generic_child_location(device_t dev, device_t child, struct sbuf *sb)
5054 {
5055 	return (0);
5056 }
5057 
5058 /**
5059  * @brief Wrapper function for BUS_GET_CPUS().
5060  *
5061  * This function simply calls the BUS_GET_CPUS() method of the
5062  * parent of @p dev.
5063  */
5064 int
5065 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5066 {
5067 	device_t parent;
5068 
5069 	parent = device_get_parent(dev);
5070 	if (parent == NULL)
5071 		return (EINVAL);
5072 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5073 }
5074 
5075 /**
5076  * @brief Wrapper function for BUS_GET_DMA_TAG().
5077  *
5078  * This function simply calls the BUS_GET_DMA_TAG() method of the
5079  * parent of @p dev.
5080  */
5081 bus_dma_tag_t
5082 bus_get_dma_tag(device_t dev)
5083 {
5084 	device_t parent;
5085 
5086 	parent = device_get_parent(dev);
5087 	if (parent == NULL)
5088 		return (NULL);
5089 	return (BUS_GET_DMA_TAG(parent, dev));
5090 }
5091 
5092 /**
5093  * @brief Wrapper function for BUS_GET_BUS_TAG().
5094  *
5095  * This function simply calls the BUS_GET_BUS_TAG() method of the
5096  * parent of @p dev.
5097  */
5098 bus_space_tag_t
5099 bus_get_bus_tag(device_t dev)
5100 {
5101 	device_t parent;
5102 
5103 	parent = device_get_parent(dev);
5104 	if (parent == NULL)
5105 		return ((bus_space_tag_t)0);
5106 	return (BUS_GET_BUS_TAG(parent, dev));
5107 }
5108 
5109 /**
5110  * @brief Wrapper function for BUS_GET_DOMAIN().
5111  *
5112  * This function simply calls the BUS_GET_DOMAIN() method of the
5113  * parent of @p dev.
5114  */
5115 int
5116 bus_get_domain(device_t dev, int *domain)
5117 {
5118 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5119 }
5120 
5121 /* Resume all devices and then notify userland that we're up again. */
5122 static int
5123 root_resume(device_t dev)
5124 {
5125 	int error;
5126 
5127 	error = bus_generic_resume(dev);
5128 	if (error == 0) {
5129 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5130 		devctl_notify("kernel", "power", "resume", NULL);
5131 	}
5132 	return (error);
5133 }
5134 
5135 static int
5136 root_print_child(device_t dev, device_t child)
5137 {
5138 	int	retval = 0;
5139 
5140 	retval += bus_print_child_header(dev, child);
5141 	retval += printf("\n");
5142 
5143 	return (retval);
5144 }
5145 
5146 static int
5147 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5148     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5149 {
5150 	/*
5151 	 * If an interrupt mapping gets to here something bad has happened.
5152 	 */
5153 	panic("root_setup_intr");
5154 }
5155 
5156 /*
5157  * If we get here, assume that the device is permanent and really is
5158  * present in the system.  Removable bus drivers are expected to intercept
5159  * this call long before it gets here.  We return -1 so that drivers that
5160  * really care can check vs -1 or some ERRNO returned higher in the food
5161  * chain.
5162  */
5163 static int
5164 root_child_present(device_t dev, device_t child)
5165 {
5166 	return (-1);
5167 }
5168 
5169 static int
5170 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5171     cpuset_t *cpuset)
5172 {
5173 	switch (op) {
5174 	case INTR_CPUS:
5175 		/* Default to returning the set of all CPUs. */
5176 		if (setsize != sizeof(cpuset_t))
5177 			return (EINVAL);
5178 		*cpuset = all_cpus;
5179 		return (0);
5180 	default:
5181 		return (EINVAL);
5182 	}
5183 }
5184 
5185 static kobj_method_t root_methods[] = {
5186 	/* Device interface */
5187 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5188 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5189 	KOBJMETHOD(device_resume,	root_resume),
5190 
5191 	/* Bus interface */
5192 	KOBJMETHOD(bus_print_child,	root_print_child),
5193 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5194 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5195 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5196 	KOBJMETHOD(bus_child_present,	root_child_present),
5197 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5198 
5199 	KOBJMETHOD_END
5200 };
5201 
5202 static driver_t root_driver = {
5203 	"root",
5204 	root_methods,
5205 	1,			/* no softc */
5206 };
5207 
5208 device_t	root_bus;
5209 devclass_t	root_devclass;
5210 
5211 static int
5212 root_bus_module_handler(module_t mod, int what, void* arg)
5213 {
5214 	switch (what) {
5215 	case MOD_LOAD:
5216 		TAILQ_INIT(&bus_data_devices);
5217 		kobj_class_compile((kobj_class_t) &root_driver);
5218 		root_bus = make_device(NULL, "root", 0);
5219 		root_bus->desc = "System root bus";
5220 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5221 		root_bus->driver = &root_driver;
5222 		root_bus->state = DS_ATTACHED;
5223 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5224 		devinit();
5225 		return (0);
5226 
5227 	case MOD_SHUTDOWN:
5228 		device_shutdown(root_bus);
5229 		return (0);
5230 	default:
5231 		return (EOPNOTSUPP);
5232 	}
5233 
5234 	return (0);
5235 }
5236 
5237 static moduledata_t root_bus_mod = {
5238 	"rootbus",
5239 	root_bus_module_handler,
5240 	NULL
5241 };
5242 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5243 
5244 /**
5245  * @brief Automatically configure devices
5246  *
5247  * This function begins the autoconfiguration process by calling
5248  * device_probe_and_attach() for each child of the @c root0 device.
5249  */
5250 void
5251 root_bus_configure(void)
5252 {
5253 	PDEBUG(("."));
5254 
5255 	/* Eventually this will be split up, but this is sufficient for now. */
5256 	bus_set_pass(BUS_PASS_DEFAULT);
5257 }
5258 
5259 /**
5260  * @brief Module handler for registering device drivers
5261  *
5262  * This module handler is used to automatically register device
5263  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5264  * devclass_add_driver() for the driver described by the
5265  * driver_module_data structure pointed to by @p arg
5266  */
5267 int
5268 driver_module_handler(module_t mod, int what, void *arg)
5269 {
5270 	struct driver_module_data *dmd;
5271 	devclass_t bus_devclass;
5272 	kobj_class_t driver;
5273 	int error, pass;
5274 
5275 	dmd = (struct driver_module_data *)arg;
5276 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5277 	error = 0;
5278 
5279 	switch (what) {
5280 	case MOD_LOAD:
5281 		if (dmd->dmd_chainevh)
5282 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5283 
5284 		pass = dmd->dmd_pass;
5285 		driver = dmd->dmd_driver;
5286 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5287 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5288 		error = devclass_add_driver(bus_devclass, driver, pass,
5289 		    dmd->dmd_devclass);
5290 		break;
5291 
5292 	case MOD_UNLOAD:
5293 		PDEBUG(("Unloading module: driver %s from bus %s",
5294 		    DRIVERNAME(dmd->dmd_driver),
5295 		    dmd->dmd_busname));
5296 		error = devclass_delete_driver(bus_devclass,
5297 		    dmd->dmd_driver);
5298 
5299 		if (!error && dmd->dmd_chainevh)
5300 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5301 		break;
5302 	case MOD_QUIESCE:
5303 		PDEBUG(("Quiesce module: driver %s from bus %s",
5304 		    DRIVERNAME(dmd->dmd_driver),
5305 		    dmd->dmd_busname));
5306 		error = devclass_quiesce_driver(bus_devclass,
5307 		    dmd->dmd_driver);
5308 
5309 		if (!error && dmd->dmd_chainevh)
5310 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5311 		break;
5312 	default:
5313 		error = EOPNOTSUPP;
5314 		break;
5315 	}
5316 
5317 	return (error);
5318 }
5319 
5320 /**
5321  * @brief Enumerate all hinted devices for this bus.
5322  *
5323  * Walks through the hints for this bus and calls the bus_hinted_child
5324  * routine for each one it fines.  It searches first for the specific
5325  * bus that's being probed for hinted children (eg isa0), and then for
5326  * generic children (eg isa).
5327  *
5328  * @param	dev	bus device to enumerate
5329  */
5330 void
5331 bus_enumerate_hinted_children(device_t bus)
5332 {
5333 	int i;
5334 	const char *dname, *busname;
5335 	int dunit;
5336 
5337 	/*
5338 	 * enumerate all devices on the specific bus
5339 	 */
5340 	busname = device_get_nameunit(bus);
5341 	i = 0;
5342 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5343 		BUS_HINTED_CHILD(bus, dname, dunit);
5344 
5345 	/*
5346 	 * and all the generic ones.
5347 	 */
5348 	busname = device_get_name(bus);
5349 	i = 0;
5350 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5351 		BUS_HINTED_CHILD(bus, dname, dunit);
5352 }
5353 
5354 #ifdef BUS_DEBUG
5355 
5356 /* the _short versions avoid iteration by not calling anything that prints
5357  * more than oneliners. I love oneliners.
5358  */
5359 
5360 static void
5361 print_device_short(device_t dev, int indent)
5362 {
5363 	if (!dev)
5364 		return;
5365 
5366 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5367 	    dev->unit, dev->desc,
5368 	    (dev->parent? "":"no "),
5369 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5370 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5371 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5372 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5373 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5374 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5375 	    (dev->ivars? "":"no "),
5376 	    (dev->softc? "":"no "),
5377 	    dev->busy));
5378 }
5379 
5380 static void
5381 print_device(device_t dev, int indent)
5382 {
5383 	if (!dev)
5384 		return;
5385 
5386 	print_device_short(dev, indent);
5387 
5388 	indentprintf(("Parent:\n"));
5389 	print_device_short(dev->parent, indent+1);
5390 	indentprintf(("Driver:\n"));
5391 	print_driver_short(dev->driver, indent+1);
5392 	indentprintf(("Devclass:\n"));
5393 	print_devclass_short(dev->devclass, indent+1);
5394 }
5395 
5396 void
5397 print_device_tree_short(device_t dev, int indent)
5398 /* print the device and all its children (indented) */
5399 {
5400 	device_t child;
5401 
5402 	if (!dev)
5403 		return;
5404 
5405 	print_device_short(dev, indent);
5406 
5407 	TAILQ_FOREACH(child, &dev->children, link) {
5408 		print_device_tree_short(child, indent+1);
5409 	}
5410 }
5411 
5412 void
5413 print_device_tree(device_t dev, int indent)
5414 /* print the device and all its children (indented) */
5415 {
5416 	device_t child;
5417 
5418 	if (!dev)
5419 		return;
5420 
5421 	print_device(dev, indent);
5422 
5423 	TAILQ_FOREACH(child, &dev->children, link) {
5424 		print_device_tree(child, indent+1);
5425 	}
5426 }
5427 
5428 static void
5429 print_driver_short(driver_t *driver, int indent)
5430 {
5431 	if (!driver)
5432 		return;
5433 
5434 	indentprintf(("driver %s: softc size = %zd\n",
5435 	    driver->name, driver->size));
5436 }
5437 
5438 static void
5439 print_driver(driver_t *driver, int indent)
5440 {
5441 	if (!driver)
5442 		return;
5443 
5444 	print_driver_short(driver, indent);
5445 }
5446 
5447 static void
5448 print_driver_list(driver_list_t drivers, int indent)
5449 {
5450 	driverlink_t driver;
5451 
5452 	TAILQ_FOREACH(driver, &drivers, link) {
5453 		print_driver(driver->driver, indent);
5454 	}
5455 }
5456 
5457 static void
5458 print_devclass_short(devclass_t dc, int indent)
5459 {
5460 	if ( !dc )
5461 		return;
5462 
5463 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5464 }
5465 
5466 static void
5467 print_devclass(devclass_t dc, int indent)
5468 {
5469 	int i;
5470 
5471 	if ( !dc )
5472 		return;
5473 
5474 	print_devclass_short(dc, indent);
5475 	indentprintf(("Drivers:\n"));
5476 	print_driver_list(dc->drivers, indent+1);
5477 
5478 	indentprintf(("Devices:\n"));
5479 	for (i = 0; i < dc->maxunit; i++)
5480 		if (dc->devices[i])
5481 			print_device(dc->devices[i], indent+1);
5482 }
5483 
5484 void
5485 print_devclass_list_short(void)
5486 {
5487 	devclass_t dc;
5488 
5489 	printf("Short listing of devclasses, drivers & devices:\n");
5490 	TAILQ_FOREACH(dc, &devclasses, link) {
5491 		print_devclass_short(dc, 0);
5492 	}
5493 }
5494 
5495 void
5496 print_devclass_list(void)
5497 {
5498 	devclass_t dc;
5499 
5500 	printf("Full listing of devclasses, drivers & devices:\n");
5501 	TAILQ_FOREACH(dc, &devclasses, link) {
5502 		print_devclass(dc, 0);
5503 	}
5504 }
5505 
5506 #endif
5507 
5508 /*
5509  * User-space access to the device tree.
5510  *
5511  * We implement a small set of nodes:
5512  *
5513  * hw.bus			Single integer read method to obtain the
5514  *				current generation count.
5515  * hw.bus.devices		Reads the entire device tree in flat space.
5516  * hw.bus.rman			Resource manager interface
5517  *
5518  * We might like to add the ability to scan devclasses and/or drivers to
5519  * determine what else is currently loaded/available.
5520  */
5521 
5522 static int
5523 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5524 {
5525 	struct u_businfo	ubus;
5526 
5527 	ubus.ub_version = BUS_USER_VERSION;
5528 	ubus.ub_generation = bus_data_generation;
5529 
5530 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5531 }
5532 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5533     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5534     "bus-related data");
5535 
5536 static int
5537 sysctl_devices(SYSCTL_HANDLER_ARGS)
5538 {
5539 	struct sbuf		sb;
5540 	int			*name = (int *)arg1;
5541 	u_int			namelen = arg2;
5542 	int			index;
5543 	device_t		dev;
5544 	struct u_device		*udev;
5545 	int			error;
5546 
5547 	if (namelen != 2)
5548 		return (EINVAL);
5549 
5550 	if (bus_data_generation_check(name[0]))
5551 		return (EINVAL);
5552 
5553 	index = name[1];
5554 
5555 	/*
5556 	 * Scan the list of devices, looking for the requested index.
5557 	 */
5558 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5559 		if (index-- == 0)
5560 			break;
5561 	}
5562 	if (dev == NULL)
5563 		return (ENOENT);
5564 
5565 	/*
5566 	 * Populate the return item, careful not to overflow the buffer.
5567 	 */
5568 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5569 	if (udev == NULL)
5570 		return (ENOMEM);
5571 	udev->dv_handle = (uintptr_t)dev;
5572 	udev->dv_parent = (uintptr_t)dev->parent;
5573 	udev->dv_devflags = dev->devflags;
5574 	udev->dv_flags = dev->flags;
5575 	udev->dv_state = dev->state;
5576 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5577 	if (dev->nameunit != NULL)
5578 		sbuf_cat(&sb, dev->nameunit);
5579 	sbuf_putc(&sb, '\0');
5580 	if (dev->desc != NULL)
5581 		sbuf_cat(&sb, dev->desc);
5582 	sbuf_putc(&sb, '\0');
5583 	if (dev->driver != NULL)
5584 		sbuf_cat(&sb, dev->driver->name);
5585 	sbuf_putc(&sb, '\0');
5586 	bus_child_pnpinfo(dev, &sb);
5587 	sbuf_putc(&sb, '\0');
5588 	bus_child_location(dev, &sb);
5589 	sbuf_putc(&sb, '\0');
5590 	error = sbuf_finish(&sb);
5591 	if (error == 0)
5592 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5593 	sbuf_delete(&sb);
5594 	free(udev, M_BUS);
5595 	return (error);
5596 }
5597 
5598 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5599     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5600     "system device tree");
5601 
5602 int
5603 bus_data_generation_check(int generation)
5604 {
5605 	if (generation != bus_data_generation)
5606 		return (1);
5607 
5608 	/* XXX generate optimised lists here? */
5609 	return (0);
5610 }
5611 
5612 void
5613 bus_data_generation_update(void)
5614 {
5615 	atomic_add_int(&bus_data_generation, 1);
5616 }
5617 
5618 int
5619 bus_free_resource(device_t dev, int type, struct resource *r)
5620 {
5621 	if (r == NULL)
5622 		return (0);
5623 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5624 }
5625 
5626 device_t
5627 device_lookup_by_name(const char *name)
5628 {
5629 	device_t dev;
5630 
5631 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5632 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5633 			return (dev);
5634 	}
5635 	return (NULL);
5636 }
5637 
5638 /*
5639  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5640  * implicit semantics on open, so it could not be reused for this.
5641  * Another option would be to call this /dev/bus?
5642  */
5643 static int
5644 find_device(struct devreq *req, device_t *devp)
5645 {
5646 	device_t dev;
5647 
5648 	/*
5649 	 * First, ensure that the name is nul terminated.
5650 	 */
5651 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5652 		return (EINVAL);
5653 
5654 	/*
5655 	 * Second, try to find an attached device whose name matches
5656 	 * 'name'.
5657 	 */
5658 	dev = device_lookup_by_name(req->dr_name);
5659 	if (dev != NULL) {
5660 		*devp = dev;
5661 		return (0);
5662 	}
5663 
5664 	/* Finally, give device enumerators a chance. */
5665 	dev = NULL;
5666 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5667 	if (dev == NULL)
5668 		return (ENOENT);
5669 	*devp = dev;
5670 	return (0);
5671 }
5672 
5673 static bool
5674 driver_exists(device_t bus, const char *driver)
5675 {
5676 	devclass_t dc;
5677 
5678 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5679 		if (devclass_find_driver_internal(dc, driver) != NULL)
5680 			return (true);
5681 	}
5682 	return (false);
5683 }
5684 
5685 static void
5686 device_gen_nomatch(device_t dev)
5687 {
5688 	device_t child;
5689 
5690 	if (dev->flags & DF_NEEDNOMATCH &&
5691 	    dev->state == DS_NOTPRESENT) {
5692 		BUS_PROBE_NOMATCH(dev->parent, dev);
5693 		devnomatch(dev);
5694 		dev->flags |= DF_DONENOMATCH;
5695 	}
5696 	dev->flags &= ~DF_NEEDNOMATCH;
5697 	TAILQ_FOREACH(child, &dev->children, link) {
5698 		device_gen_nomatch(child);
5699 	}
5700 }
5701 
5702 static void
5703 device_do_deferred_actions(void)
5704 {
5705 	devclass_t dc;
5706 	driverlink_t dl;
5707 
5708 	/*
5709 	 * Walk through the devclasses to find all the drivers we've tagged as
5710 	 * deferred during the freeze and call the driver added routines. They
5711 	 * have already been added to the lists in the background, so the driver
5712 	 * added routines that trigger a probe will have all the right bidders
5713 	 * for the probe auction.
5714 	 */
5715 	TAILQ_FOREACH(dc, &devclasses, link) {
5716 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5717 			if (dl->flags & DL_DEFERRED_PROBE) {
5718 				devclass_driver_added(dc, dl->driver);
5719 				dl->flags &= ~DL_DEFERRED_PROBE;
5720 			}
5721 		}
5722 	}
5723 
5724 	/*
5725 	 * We also defer no-match events during a freeze. Walk the tree and
5726 	 * generate all the pent-up events that are still relevant.
5727 	 */
5728 	device_gen_nomatch(root_bus);
5729 	bus_data_generation_update();
5730 }
5731 
5732 static int
5733 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5734     struct thread *td)
5735 {
5736 	struct devreq *req;
5737 	device_t dev;
5738 	int error, old;
5739 
5740 	/* Locate the device to control. */
5741 	bus_topo_lock();
5742 	req = (struct devreq *)data;
5743 	switch (cmd) {
5744 	case DEV_ATTACH:
5745 	case DEV_DETACH:
5746 	case DEV_ENABLE:
5747 	case DEV_DISABLE:
5748 	case DEV_SUSPEND:
5749 	case DEV_RESUME:
5750 	case DEV_SET_DRIVER:
5751 	case DEV_CLEAR_DRIVER:
5752 	case DEV_RESCAN:
5753 	case DEV_DELETE:
5754 	case DEV_RESET:
5755 		error = priv_check(td, PRIV_DRIVER);
5756 		if (error == 0)
5757 			error = find_device(req, &dev);
5758 		break;
5759 	case DEV_FREEZE:
5760 	case DEV_THAW:
5761 		error = priv_check(td, PRIV_DRIVER);
5762 		break;
5763 	default:
5764 		error = ENOTTY;
5765 		break;
5766 	}
5767 	if (error) {
5768 		bus_topo_unlock();
5769 		return (error);
5770 	}
5771 
5772 	/* Perform the requested operation. */
5773 	switch (cmd) {
5774 	case DEV_ATTACH:
5775 		if (device_is_attached(dev))
5776 			error = EBUSY;
5777 		else if (!device_is_enabled(dev))
5778 			error = ENXIO;
5779 		else
5780 			error = device_probe_and_attach(dev);
5781 		break;
5782 	case DEV_DETACH:
5783 		if (!device_is_attached(dev)) {
5784 			error = ENXIO;
5785 			break;
5786 		}
5787 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5788 			error = device_quiesce(dev);
5789 			if (error)
5790 				break;
5791 		}
5792 		error = device_detach(dev);
5793 		break;
5794 	case DEV_ENABLE:
5795 		if (device_is_enabled(dev)) {
5796 			error = EBUSY;
5797 			break;
5798 		}
5799 
5800 		/*
5801 		 * If the device has been probed but not attached (e.g.
5802 		 * when it has been disabled by a loader hint), just
5803 		 * attach the device rather than doing a full probe.
5804 		 */
5805 		device_enable(dev);
5806 		if (device_is_alive(dev)) {
5807 			/*
5808 			 * If the device was disabled via a hint, clear
5809 			 * the hint.
5810 			 */
5811 			if (resource_disabled(dev->driver->name, dev->unit))
5812 				resource_unset_value(dev->driver->name,
5813 				    dev->unit, "disabled");
5814 			error = device_attach(dev);
5815 		} else
5816 			error = device_probe_and_attach(dev);
5817 		break;
5818 	case DEV_DISABLE:
5819 		if (!device_is_enabled(dev)) {
5820 			error = ENXIO;
5821 			break;
5822 		}
5823 
5824 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5825 			error = device_quiesce(dev);
5826 			if (error)
5827 				break;
5828 		}
5829 
5830 		/*
5831 		 * Force DF_FIXEDCLASS on around detach to preserve
5832 		 * the existing name.
5833 		 */
5834 		old = dev->flags;
5835 		dev->flags |= DF_FIXEDCLASS;
5836 		error = device_detach(dev);
5837 		if (!(old & DF_FIXEDCLASS))
5838 			dev->flags &= ~DF_FIXEDCLASS;
5839 		if (error == 0)
5840 			device_disable(dev);
5841 		break;
5842 	case DEV_SUSPEND:
5843 		if (device_is_suspended(dev)) {
5844 			error = EBUSY;
5845 			break;
5846 		}
5847 		if (device_get_parent(dev) == NULL) {
5848 			error = EINVAL;
5849 			break;
5850 		}
5851 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5852 		break;
5853 	case DEV_RESUME:
5854 		if (!device_is_suspended(dev)) {
5855 			error = EINVAL;
5856 			break;
5857 		}
5858 		if (device_get_parent(dev) == NULL) {
5859 			error = EINVAL;
5860 			break;
5861 		}
5862 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5863 		break;
5864 	case DEV_SET_DRIVER: {
5865 		devclass_t dc;
5866 		char driver[128];
5867 
5868 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5869 		if (error)
5870 			break;
5871 		if (driver[0] == '\0') {
5872 			error = EINVAL;
5873 			break;
5874 		}
5875 		if (dev->devclass != NULL &&
5876 		    strcmp(driver, dev->devclass->name) == 0)
5877 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5878 			break;
5879 
5880 		/*
5881 		 * Scan drivers for this device's bus looking for at
5882 		 * least one matching driver.
5883 		 */
5884 		if (dev->parent == NULL) {
5885 			error = EINVAL;
5886 			break;
5887 		}
5888 		if (!driver_exists(dev->parent, driver)) {
5889 			error = ENOENT;
5890 			break;
5891 		}
5892 		dc = devclass_create(driver);
5893 		if (dc == NULL) {
5894 			error = ENOMEM;
5895 			break;
5896 		}
5897 
5898 		/* Detach device if necessary. */
5899 		if (device_is_attached(dev)) {
5900 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5901 				error = device_detach(dev);
5902 			else
5903 				error = EBUSY;
5904 			if (error)
5905 				break;
5906 		}
5907 
5908 		/* Clear any previously-fixed device class and unit. */
5909 		if (dev->flags & DF_FIXEDCLASS)
5910 			devclass_delete_device(dev->devclass, dev);
5911 		dev->flags |= DF_WILDCARD;
5912 		dev->unit = -1;
5913 
5914 		/* Force the new device class. */
5915 		error = devclass_add_device(dc, dev);
5916 		if (error)
5917 			break;
5918 		dev->flags |= DF_FIXEDCLASS;
5919 		error = device_probe_and_attach(dev);
5920 		break;
5921 	}
5922 	case DEV_CLEAR_DRIVER:
5923 		if (!(dev->flags & DF_FIXEDCLASS)) {
5924 			error = 0;
5925 			break;
5926 		}
5927 		if (device_is_attached(dev)) {
5928 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5929 				error = device_detach(dev);
5930 			else
5931 				error = EBUSY;
5932 			if (error)
5933 				break;
5934 		}
5935 
5936 		dev->flags &= ~DF_FIXEDCLASS;
5937 		dev->flags |= DF_WILDCARD;
5938 		devclass_delete_device(dev->devclass, dev);
5939 		error = device_probe_and_attach(dev);
5940 		break;
5941 	case DEV_RESCAN:
5942 		if (!device_is_attached(dev)) {
5943 			error = ENXIO;
5944 			break;
5945 		}
5946 		error = BUS_RESCAN(dev);
5947 		break;
5948 	case DEV_DELETE: {
5949 		device_t parent;
5950 
5951 		parent = device_get_parent(dev);
5952 		if (parent == NULL) {
5953 			error = EINVAL;
5954 			break;
5955 		}
5956 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5957 			if (bus_child_present(dev) != 0) {
5958 				error = EBUSY;
5959 				break;
5960 			}
5961 		}
5962 
5963 		error = device_delete_child(parent, dev);
5964 		break;
5965 	}
5966 	case DEV_FREEZE:
5967 		if (device_frozen)
5968 			error = EBUSY;
5969 		else
5970 			device_frozen = true;
5971 		break;
5972 	case DEV_THAW:
5973 		if (!device_frozen)
5974 			error = EBUSY;
5975 		else {
5976 			device_do_deferred_actions();
5977 			device_frozen = false;
5978 		}
5979 		break;
5980 	case DEV_RESET:
5981 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5982 			error = EINVAL;
5983 			break;
5984 		}
5985 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5986 		    req->dr_flags);
5987 		break;
5988 	}
5989 	bus_topo_unlock();
5990 	return (error);
5991 }
5992 
5993 static struct cdevsw devctl2_cdevsw = {
5994 	.d_version =	D_VERSION,
5995 	.d_ioctl =	devctl2_ioctl,
5996 	.d_name =	"devctl2",
5997 };
5998 
5999 static void
6000 devctl2_init(void)
6001 {
6002 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
6003 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
6004 }
6005 
6006 /*
6007  * APIs to manage deprecation and obsolescence.
6008  */
6009 static int obsolete_panic = 0;
6010 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
6011     "Panic when obsolete features are used (0 = never, 1 = if obsolete, "
6012     "2 = if deprecated)");
6013 
6014 static void
6015 gone_panic(int major, int running, const char *msg)
6016 {
6017 	switch (obsolete_panic)
6018 	{
6019 	case 0:
6020 		return;
6021 	case 1:
6022 		if (running < major)
6023 			return;
6024 		/* FALLTHROUGH */
6025 	default:
6026 		panic("%s", msg);
6027 	}
6028 }
6029 
6030 void
6031 _gone_in(int major, const char *msg)
6032 {
6033 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6034 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6035 		printf("Obsolete code will be removed soon: %s\n", msg);
6036 	else
6037 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6038 		    major, msg);
6039 }
6040 
6041 void
6042 _gone_in_dev(device_t dev, int major, const char *msg)
6043 {
6044 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6045 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6046 		device_printf(dev,
6047 		    "Obsolete code will be removed soon: %s\n", msg);
6048 	else
6049 		device_printf(dev,
6050 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6051 		    major, msg);
6052 }
6053 
6054 #ifdef DDB
6055 DB_SHOW_COMMAND(device, db_show_device)
6056 {
6057 	device_t dev;
6058 
6059 	if (!have_addr)
6060 		return;
6061 
6062 	dev = (device_t)addr;
6063 
6064 	db_printf("name:    %s\n", device_get_nameunit(dev));
6065 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6066 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6067 	db_printf("  addr:    %p\n", dev);
6068 	db_printf("  parent:  %p\n", dev->parent);
6069 	db_printf("  softc:   %p\n", dev->softc);
6070 	db_printf("  ivars:   %p\n", dev->ivars);
6071 }
6072 
6073 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6074 {
6075 	device_t dev;
6076 
6077 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6078 		db_show_device((db_expr_t)dev, true, count, modif);
6079 	}
6080 }
6081 #endif
6082