xref: /freebsd/sys/kern/subr_bus.c (revision da5137ab)
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     device_property_type_t type)
2722 {
2723 	device_t bus = device_get_parent(dev);
2724 
2725 	switch (type) {
2726 	case DEVICE_PROP_ANY:
2727 	case DEVICE_PROP_BUFFER:
2728 		break;
2729 	case DEVICE_PROP_UINT32:
2730 		if (sz % 4 != 0)
2731 			return (-1);
2732 		break;
2733 	case DEVICE_PROP_UINT64:
2734 		if (sz % 8 != 0)
2735 			return (-1);
2736 		break;
2737 	default:
2738 		return (-1);
2739 	}
2740 
2741 	return (BUS_GET_PROPERTY(bus, dev, prop, val, sz, type));
2742 }
2743 
2744 bool
2745 device_has_property(device_t dev, const char *prop)
2746 {
2747 	return (device_get_property(dev, prop, NULL, 0, DEVICE_PROP_ANY) >= 0);
2748 }
2749 
2750 /**
2751  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2752  */
2753 int
2754 device_has_quiet_children(device_t dev)
2755 {
2756 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2757 }
2758 
2759 /**
2760  * @brief Return non-zero if the DF_QUIET flag is set on the device
2761  */
2762 int
2763 device_is_quiet(device_t dev)
2764 {
2765 	return ((dev->flags & DF_QUIET) != 0);
2766 }
2767 
2768 /**
2769  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2770  */
2771 int
2772 device_is_enabled(device_t dev)
2773 {
2774 	return ((dev->flags & DF_ENABLED) != 0);
2775 }
2776 
2777 /**
2778  * @brief Return non-zero if the device was successfully probed
2779  */
2780 int
2781 device_is_alive(device_t dev)
2782 {
2783 	return (dev->state >= DS_ALIVE);
2784 }
2785 
2786 /**
2787  * @brief Return non-zero if the device currently has a driver
2788  * attached to it
2789  */
2790 int
2791 device_is_attached(device_t dev)
2792 {
2793 	return (dev->state >= DS_ATTACHED);
2794 }
2795 
2796 /**
2797  * @brief Return non-zero if the device is currently suspended.
2798  */
2799 int
2800 device_is_suspended(device_t dev)
2801 {
2802 	return ((dev->flags & DF_SUSPENDED) != 0);
2803 }
2804 
2805 /**
2806  * @brief Set the devclass of a device
2807  * @see devclass_add_device().
2808  */
2809 int
2810 device_set_devclass(device_t dev, const char *classname)
2811 {
2812 	devclass_t dc;
2813 	int error;
2814 
2815 	if (!classname) {
2816 		if (dev->devclass)
2817 			devclass_delete_device(dev->devclass, dev);
2818 		return (0);
2819 	}
2820 
2821 	if (dev->devclass) {
2822 		printf("device_set_devclass: device class already set\n");
2823 		return (EINVAL);
2824 	}
2825 
2826 	dc = devclass_find_internal(classname, NULL, TRUE);
2827 	if (!dc)
2828 		return (ENOMEM);
2829 
2830 	error = devclass_add_device(dc, dev);
2831 
2832 	bus_data_generation_update();
2833 	return (error);
2834 }
2835 
2836 /**
2837  * @brief Set the devclass of a device and mark the devclass fixed.
2838  * @see device_set_devclass()
2839  */
2840 int
2841 device_set_devclass_fixed(device_t dev, const char *classname)
2842 {
2843 	int error;
2844 
2845 	if (classname == NULL)
2846 		return (EINVAL);
2847 
2848 	error = device_set_devclass(dev, classname);
2849 	if (error)
2850 		return (error);
2851 	dev->flags |= DF_FIXEDCLASS;
2852 	return (0);
2853 }
2854 
2855 /**
2856  * @brief Query the device to determine if it's of a fixed devclass
2857  * @see device_set_devclass_fixed()
2858  */
2859 bool
2860 device_is_devclass_fixed(device_t dev)
2861 {
2862 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2863 }
2864 
2865 /**
2866  * @brief Set the driver of a device
2867  *
2868  * @retval 0		success
2869  * @retval EBUSY	the device already has a driver attached
2870  * @retval ENOMEM	a memory allocation failure occurred
2871  */
2872 int
2873 device_set_driver(device_t dev, driver_t *driver)
2874 {
2875 	int domain;
2876 	struct domainset *policy;
2877 
2878 	if (dev->state >= DS_ATTACHED)
2879 		return (EBUSY);
2880 
2881 	if (dev->driver == driver)
2882 		return (0);
2883 
2884 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2885 		free(dev->softc, M_BUS_SC);
2886 		dev->softc = NULL;
2887 	}
2888 	device_set_desc(dev, NULL);
2889 	kobj_delete((kobj_t) dev, NULL);
2890 	dev->driver = driver;
2891 	if (driver) {
2892 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2893 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2894 			if (bus_get_domain(dev, &domain) == 0)
2895 				policy = DOMAINSET_PREF(domain);
2896 			else
2897 				policy = DOMAINSET_RR();
2898 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2899 			    policy, M_NOWAIT | M_ZERO);
2900 			if (!dev->softc) {
2901 				kobj_delete((kobj_t) dev, NULL);
2902 				kobj_init((kobj_t) dev, &null_class);
2903 				dev->driver = NULL;
2904 				return (ENOMEM);
2905 			}
2906 		}
2907 	} else {
2908 		kobj_init((kobj_t) dev, &null_class);
2909 	}
2910 
2911 	bus_data_generation_update();
2912 	return (0);
2913 }
2914 
2915 /**
2916  * @brief Probe a device, and return this status.
2917  *
2918  * This function is the core of the device autoconfiguration
2919  * system. Its purpose is to select a suitable driver for a device and
2920  * then call that driver to initialise the hardware appropriately. The
2921  * driver is selected by calling the DEVICE_PROBE() method of a set of
2922  * candidate drivers and then choosing the driver which returned the
2923  * best value. This driver is then attached to the device using
2924  * device_attach().
2925  *
2926  * The set of suitable drivers is taken from the list of drivers in
2927  * the parent device's devclass. If the device was originally created
2928  * with a specific class name (see device_add_child()), only drivers
2929  * with that name are probed, otherwise all drivers in the devclass
2930  * are probed. If no drivers return successful probe values in the
2931  * parent devclass, the search continues in the parent of that
2932  * devclass (see devclass_get_parent()) if any.
2933  *
2934  * @param dev		the device to initialise
2935  *
2936  * @retval 0		success
2937  * @retval ENXIO	no driver was found
2938  * @retval ENOMEM	memory allocation failure
2939  * @retval non-zero	some other unix error code
2940  * @retval -1		Device already attached
2941  */
2942 int
2943 device_probe(device_t dev)
2944 {
2945 	int error;
2946 
2947 	bus_topo_assert();
2948 
2949 	if (dev->state >= DS_ALIVE)
2950 		return (-1);
2951 
2952 	if (!(dev->flags & DF_ENABLED)) {
2953 		if (bootverbose && device_get_name(dev) != NULL) {
2954 			device_print_prettyname(dev);
2955 			printf("not probed (disabled)\n");
2956 		}
2957 		return (-1);
2958 	}
2959 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2960 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2961 		    !(dev->flags & DF_DONENOMATCH)) {
2962 			BUS_PROBE_NOMATCH(dev->parent, dev);
2963 			devnomatch(dev);
2964 			dev->flags |= DF_DONENOMATCH;
2965 		}
2966 		return (error);
2967 	}
2968 	return (0);
2969 }
2970 
2971 /**
2972  * @brief Probe a device and attach a driver if possible
2973  *
2974  * calls device_probe() and attaches if that was successful.
2975  */
2976 int
2977 device_probe_and_attach(device_t dev)
2978 {
2979 	int error;
2980 
2981 	bus_topo_assert();
2982 
2983 	error = device_probe(dev);
2984 	if (error == -1)
2985 		return (0);
2986 	else if (error != 0)
2987 		return (error);
2988 
2989 	CURVNET_SET_QUIET(vnet0);
2990 	error = device_attach(dev);
2991 	CURVNET_RESTORE();
2992 	return error;
2993 }
2994 
2995 /**
2996  * @brief Attach a device driver to a device
2997  *
2998  * This function is a wrapper around the DEVICE_ATTACH() driver
2999  * method. In addition to calling DEVICE_ATTACH(), it initialises the
3000  * device's sysctl tree, optionally prints a description of the device
3001  * and queues a notification event for user-based device management
3002  * services.
3003  *
3004  * Normally this function is only called internally from
3005  * device_probe_and_attach().
3006  *
3007  * @param dev		the device to initialise
3008  *
3009  * @retval 0		success
3010  * @retval ENXIO	no driver was found
3011  * @retval ENOMEM	memory allocation failure
3012  * @retval non-zero	some other unix error code
3013  */
3014 int
3015 device_attach(device_t dev)
3016 {
3017 	uint64_t attachtime;
3018 	uint16_t attachentropy;
3019 	int error;
3020 
3021 	if (resource_disabled(dev->driver->name, dev->unit)) {
3022 		device_disable(dev);
3023 		if (bootverbose)
3024 			 device_printf(dev, "disabled via hints entry\n");
3025 		return (ENXIO);
3026 	}
3027 
3028 	device_sysctl_init(dev);
3029 	if (!device_is_quiet(dev))
3030 		device_print_child(dev->parent, dev);
3031 	attachtime = get_cyclecount();
3032 	dev->state = DS_ATTACHING;
3033 	if ((error = DEVICE_ATTACH(dev)) != 0) {
3034 		printf("device_attach: %s%d attach returned %d\n",
3035 		    dev->driver->name, dev->unit, error);
3036 		if (!(dev->flags & DF_FIXEDCLASS))
3037 			devclass_delete_device(dev->devclass, dev);
3038 		(void)device_set_driver(dev, NULL);
3039 		device_sysctl_fini(dev);
3040 		KASSERT(dev->busy == 0, ("attach failed but busy"));
3041 		dev->state = DS_NOTPRESENT;
3042 		return (error);
3043 	}
3044 	dev->flags |= DF_ATTACHED_ONCE;
3045 	/* We only need the low bits of this time, but ranges from tens to thousands
3046 	 * have been seen, so keep 2 bytes' worth.
3047 	 */
3048 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3049 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3050 	device_sysctl_update(dev);
3051 	dev->state = DS_ATTACHED;
3052 	dev->flags &= ~DF_DONENOMATCH;
3053 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3054 	devadded(dev);
3055 	return (0);
3056 }
3057 
3058 /**
3059  * @brief Detach a driver from a device
3060  *
3061  * This function is a wrapper around the DEVICE_DETACH() driver
3062  * method. If the call to DEVICE_DETACH() succeeds, it calls
3063  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3064  * notification event for user-based device management services and
3065  * cleans up the device's sysctl tree.
3066  *
3067  * @param dev		the device to un-initialise
3068  *
3069  * @retval 0		success
3070  * @retval ENXIO	no driver was found
3071  * @retval ENOMEM	memory allocation failure
3072  * @retval non-zero	some other unix error code
3073  */
3074 int
3075 device_detach(device_t dev)
3076 {
3077 	int error;
3078 
3079 	bus_topo_assert();
3080 
3081 	PDEBUG(("%s", DEVICENAME(dev)));
3082 	if (dev->busy > 0)
3083 		return (EBUSY);
3084 	if (dev->state == DS_ATTACHING) {
3085 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3086 		return (EBUSY);
3087 	}
3088 	if (dev->state != DS_ATTACHED)
3089 		return (0);
3090 
3091 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3092 	if ((error = DEVICE_DETACH(dev)) != 0) {
3093 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3094 		    EVHDEV_DETACH_FAILED);
3095 		return (error);
3096 	} else {
3097 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3098 		    EVHDEV_DETACH_COMPLETE);
3099 	}
3100 	devremoved(dev);
3101 	if (!device_is_quiet(dev))
3102 		device_printf(dev, "detached\n");
3103 	if (dev->parent)
3104 		BUS_CHILD_DETACHED(dev->parent, dev);
3105 
3106 	if (!(dev->flags & DF_FIXEDCLASS))
3107 		devclass_delete_device(dev->devclass, dev);
3108 
3109 	device_verbose(dev);
3110 	dev->state = DS_NOTPRESENT;
3111 	(void)device_set_driver(dev, NULL);
3112 	device_sysctl_fini(dev);
3113 
3114 	return (0);
3115 }
3116 
3117 /**
3118  * @brief Tells a driver to quiesce itself.
3119  *
3120  * This function is a wrapper around the DEVICE_QUIESCE() driver
3121  * method. If the call to DEVICE_QUIESCE() succeeds.
3122  *
3123  * @param dev		the device to quiesce
3124  *
3125  * @retval 0		success
3126  * @retval ENXIO	no driver was found
3127  * @retval ENOMEM	memory allocation failure
3128  * @retval non-zero	some other unix error code
3129  */
3130 int
3131 device_quiesce(device_t dev)
3132 {
3133 	PDEBUG(("%s", DEVICENAME(dev)));
3134 	if (dev->busy > 0)
3135 		return (EBUSY);
3136 	if (dev->state != DS_ATTACHED)
3137 		return (0);
3138 
3139 	return (DEVICE_QUIESCE(dev));
3140 }
3141 
3142 /**
3143  * @brief Notify a device of system shutdown
3144  *
3145  * This function calls the DEVICE_SHUTDOWN() driver method if the
3146  * device currently has an attached driver.
3147  *
3148  * @returns the value returned by DEVICE_SHUTDOWN()
3149  */
3150 int
3151 device_shutdown(device_t dev)
3152 {
3153 	if (dev->state < DS_ATTACHED)
3154 		return (0);
3155 	return (DEVICE_SHUTDOWN(dev));
3156 }
3157 
3158 /**
3159  * @brief Set the unit number of a device
3160  *
3161  * This function can be used to override the unit number used for a
3162  * device (e.g. to wire a device to a pre-configured unit number).
3163  */
3164 int
3165 device_set_unit(device_t dev, int unit)
3166 {
3167 	devclass_t dc;
3168 	int err;
3169 
3170 	if (unit == dev->unit)
3171 		return (0);
3172 	dc = device_get_devclass(dev);
3173 	if (unit < dc->maxunit && dc->devices[unit])
3174 		return (EBUSY);
3175 	err = devclass_delete_device(dc, dev);
3176 	if (err)
3177 		return (err);
3178 	dev->unit = unit;
3179 	err = devclass_add_device(dc, dev);
3180 	if (err)
3181 		return (err);
3182 
3183 	bus_data_generation_update();
3184 	return (0);
3185 }
3186 
3187 /*======================================*/
3188 /*
3189  * Some useful method implementations to make life easier for bus drivers.
3190  */
3191 
3192 void
3193 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3194 {
3195 	bzero(args, sz);
3196 	args->size = sz;
3197 	args->memattr = VM_MEMATTR_DEVICE;
3198 }
3199 
3200 /**
3201  * @brief Initialise a resource list.
3202  *
3203  * @param rl		the resource list to initialise
3204  */
3205 void
3206 resource_list_init(struct resource_list *rl)
3207 {
3208 	STAILQ_INIT(rl);
3209 }
3210 
3211 /**
3212  * @brief Reclaim memory used by a resource list.
3213  *
3214  * This function frees the memory for all resource entries on the list
3215  * (if any).
3216  *
3217  * @param rl		the resource list to free
3218  */
3219 void
3220 resource_list_free(struct resource_list *rl)
3221 {
3222 	struct resource_list_entry *rle;
3223 
3224 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3225 		if (rle->res)
3226 			panic("resource_list_free: resource entry is busy");
3227 		STAILQ_REMOVE_HEAD(rl, link);
3228 		free(rle, M_BUS);
3229 	}
3230 }
3231 
3232 /**
3233  * @brief Add a resource entry.
3234  *
3235  * This function adds a resource entry using the given @p type, @p
3236  * start, @p end and @p count values. A rid value is chosen by
3237  * searching sequentially for the first unused rid starting at zero.
3238  *
3239  * @param rl		the resource list to edit
3240  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3241  * @param start		the start address of the resource
3242  * @param end		the end address of the resource
3243  * @param count		XXX end-start+1
3244  */
3245 int
3246 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3247     rman_res_t end, rman_res_t count)
3248 {
3249 	int rid;
3250 
3251 	rid = 0;
3252 	while (resource_list_find(rl, type, rid) != NULL)
3253 		rid++;
3254 	resource_list_add(rl, type, rid, start, end, count);
3255 	return (rid);
3256 }
3257 
3258 /**
3259  * @brief Add or modify a resource entry.
3260  *
3261  * If an existing entry exists with the same type and rid, it will be
3262  * modified using the given values of @p start, @p end and @p
3263  * count. If no entry exists, a new one will be created using the
3264  * given values.  The resource list entry that matches is then returned.
3265  *
3266  * @param rl		the resource list to edit
3267  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3268  * @param rid		the resource identifier
3269  * @param start		the start address of the resource
3270  * @param end		the end address of the resource
3271  * @param count		XXX end-start+1
3272  */
3273 struct resource_list_entry *
3274 resource_list_add(struct resource_list *rl, int type, int rid,
3275     rman_res_t start, rman_res_t end, rman_res_t count)
3276 {
3277 	struct resource_list_entry *rle;
3278 
3279 	rle = resource_list_find(rl, type, rid);
3280 	if (!rle) {
3281 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3282 		    M_NOWAIT);
3283 		if (!rle)
3284 			panic("resource_list_add: can't record entry");
3285 		STAILQ_INSERT_TAIL(rl, rle, link);
3286 		rle->type = type;
3287 		rle->rid = rid;
3288 		rle->res = NULL;
3289 		rle->flags = 0;
3290 	}
3291 
3292 	if (rle->res)
3293 		panic("resource_list_add: resource entry is busy");
3294 
3295 	rle->start = start;
3296 	rle->end = end;
3297 	rle->count = count;
3298 	return (rle);
3299 }
3300 
3301 /**
3302  * @brief Determine if a resource entry is busy.
3303  *
3304  * Returns true if a resource entry is busy meaning that it has an
3305  * associated resource that is not an unallocated "reserved" resource.
3306  *
3307  * @param rl		the resource list to search
3308  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3309  * @param rid		the resource identifier
3310  *
3311  * @returns Non-zero if the entry is busy, zero otherwise.
3312  */
3313 int
3314 resource_list_busy(struct resource_list *rl, int type, int rid)
3315 {
3316 	struct resource_list_entry *rle;
3317 
3318 	rle = resource_list_find(rl, type, rid);
3319 	if (rle == NULL || rle->res == NULL)
3320 		return (0);
3321 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3322 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3323 		    ("reserved resource is active"));
3324 		return (0);
3325 	}
3326 	return (1);
3327 }
3328 
3329 /**
3330  * @brief Determine if a resource entry is reserved.
3331  *
3332  * Returns true if a resource entry is reserved meaning that it has an
3333  * associated "reserved" resource.  The resource can either be
3334  * allocated or unallocated.
3335  *
3336  * @param rl		the resource list to search
3337  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3338  * @param rid		the resource identifier
3339  *
3340  * @returns Non-zero if the entry is reserved, zero otherwise.
3341  */
3342 int
3343 resource_list_reserved(struct resource_list *rl, int type, int rid)
3344 {
3345 	struct resource_list_entry *rle;
3346 
3347 	rle = resource_list_find(rl, type, rid);
3348 	if (rle != NULL && rle->flags & RLE_RESERVED)
3349 		return (1);
3350 	return (0);
3351 }
3352 
3353 /**
3354  * @brief Find a resource entry by type and rid.
3355  *
3356  * @param rl		the resource list to search
3357  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3358  * @param rid		the resource identifier
3359  *
3360  * @returns the resource entry pointer or NULL if there is no such
3361  * entry.
3362  */
3363 struct resource_list_entry *
3364 resource_list_find(struct resource_list *rl, int type, int rid)
3365 {
3366 	struct resource_list_entry *rle;
3367 
3368 	STAILQ_FOREACH(rle, rl, link) {
3369 		if (rle->type == type && rle->rid == rid)
3370 			return (rle);
3371 	}
3372 	return (NULL);
3373 }
3374 
3375 /**
3376  * @brief Delete a resource entry.
3377  *
3378  * @param rl		the resource list to edit
3379  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3380  * @param rid		the resource identifier
3381  */
3382 void
3383 resource_list_delete(struct resource_list *rl, int type, int rid)
3384 {
3385 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3386 
3387 	if (rle) {
3388 		if (rle->res != NULL)
3389 			panic("resource_list_delete: resource has not been released");
3390 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3391 		free(rle, M_BUS);
3392 	}
3393 }
3394 
3395 /**
3396  * @brief Allocate a reserved resource
3397  *
3398  * This can be used by buses to force the allocation of resources
3399  * that are always active in the system even if they are not allocated
3400  * by a driver (e.g. PCI BARs).  This function is usually called when
3401  * adding a new child to the bus.  The resource is allocated from the
3402  * parent bus when it is reserved.  The resource list entry is marked
3403  * with RLE_RESERVED to note that it is a reserved resource.
3404  *
3405  * Subsequent attempts to allocate the resource with
3406  * resource_list_alloc() will succeed the first time and will set
3407  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3408  * resource that has been allocated is released with
3409  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3410  * the actual resource remains allocated.  The resource can be released to
3411  * the parent bus by calling resource_list_unreserve().
3412  *
3413  * @param rl		the resource list to allocate from
3414  * @param bus		the parent device of @p child
3415  * @param child		the device for which the resource is being reserved
3416  * @param type		the type of resource to allocate
3417  * @param rid		a pointer to the resource identifier
3418  * @param start		hint at the start of the resource range - pass
3419  *			@c 0 for any start address
3420  * @param end		hint at the end of the resource range - pass
3421  *			@c ~0 for any end address
3422  * @param count		hint at the size of range required - pass @c 1
3423  *			for any size
3424  * @param flags		any extra flags to control the resource
3425  *			allocation - see @c RF_XXX flags in
3426  *			<sys/rman.h> for details
3427  *
3428  * @returns		the resource which was allocated or @c NULL if no
3429  *			resource could be allocated
3430  */
3431 struct resource *
3432 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3433     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3434 {
3435 	struct resource_list_entry *rle = NULL;
3436 	int passthrough = (device_get_parent(child) != bus);
3437 	struct resource *r;
3438 
3439 	if (passthrough)
3440 		panic(
3441     "resource_list_reserve() should only be called for direct children");
3442 	if (flags & RF_ACTIVE)
3443 		panic(
3444     "resource_list_reserve() should only reserve inactive resources");
3445 
3446 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3447 	    flags);
3448 	if (r != NULL) {
3449 		rle = resource_list_find(rl, type, *rid);
3450 		rle->flags |= RLE_RESERVED;
3451 	}
3452 	return (r);
3453 }
3454 
3455 /**
3456  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3457  *
3458  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3459  * and passing the allocation up to the parent of @p bus. This assumes
3460  * that the first entry of @c device_get_ivars(child) is a struct
3461  * resource_list. This also handles 'passthrough' allocations where a
3462  * child is a remote descendant of bus by passing the allocation up to
3463  * the parent of bus.
3464  *
3465  * Typically, a bus driver would store a list of child resources
3466  * somewhere in the child device's ivars (see device_get_ivars()) and
3467  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3468  * then call resource_list_alloc() to perform the allocation.
3469  *
3470  * @param rl		the resource list to allocate from
3471  * @param bus		the parent device of @p child
3472  * @param child		the device which is requesting an allocation
3473  * @param type		the type of resource to allocate
3474  * @param rid		a pointer to the resource identifier
3475  * @param start		hint at the start of the resource range - pass
3476  *			@c 0 for any start address
3477  * @param end		hint at the end of the resource range - pass
3478  *			@c ~0 for any end address
3479  * @param count		hint at the size of range required - pass @c 1
3480  *			for any size
3481  * @param flags		any extra flags to control the resource
3482  *			allocation - see @c RF_XXX flags in
3483  *			<sys/rman.h> for details
3484  *
3485  * @returns		the resource which was allocated or @c NULL if no
3486  *			resource could be allocated
3487  */
3488 struct resource *
3489 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3490     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3491 {
3492 	struct resource_list_entry *rle = NULL;
3493 	int passthrough = (device_get_parent(child) != bus);
3494 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3495 
3496 	if (passthrough) {
3497 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3498 		    type, rid, start, end, count, flags));
3499 	}
3500 
3501 	rle = resource_list_find(rl, type, *rid);
3502 
3503 	if (!rle)
3504 		return (NULL);		/* no resource of that type/rid */
3505 
3506 	if (rle->res) {
3507 		if (rle->flags & RLE_RESERVED) {
3508 			if (rle->flags & RLE_ALLOCATED)
3509 				return (NULL);
3510 			if ((flags & RF_ACTIVE) &&
3511 			    bus_activate_resource(child, type, *rid,
3512 			    rle->res) != 0)
3513 				return (NULL);
3514 			rle->flags |= RLE_ALLOCATED;
3515 			return (rle->res);
3516 		}
3517 		device_printf(bus,
3518 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3519 		    type, device_get_nameunit(child));
3520 		return (NULL);
3521 	}
3522 
3523 	if (isdefault) {
3524 		start = rle->start;
3525 		count = ulmax(count, rle->count);
3526 		end = ulmax(rle->end, start + count - 1);
3527 	}
3528 
3529 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3530 	    type, rid, start, end, count, flags);
3531 
3532 	/*
3533 	 * Record the new range.
3534 	 */
3535 	if (rle->res) {
3536 		rle->start = rman_get_start(rle->res);
3537 		rle->end = rman_get_end(rle->res);
3538 		rle->count = count;
3539 	}
3540 
3541 	return (rle->res);
3542 }
3543 
3544 /**
3545  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3546  *
3547  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3548  * used with resource_list_alloc().
3549  *
3550  * @param rl		the resource list which was allocated from
3551  * @param bus		the parent device of @p child
3552  * @param child		the device which is requesting a release
3553  * @param type		the type of resource to release
3554  * @param rid		the resource identifier
3555  * @param res		the resource to release
3556  *
3557  * @retval 0		success
3558  * @retval non-zero	a standard unix error code indicating what
3559  *			error condition prevented the operation
3560  */
3561 int
3562 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3563     int type, int rid, struct resource *res)
3564 {
3565 	struct resource_list_entry *rle = NULL;
3566 	int passthrough = (device_get_parent(child) != bus);
3567 	int error;
3568 
3569 	if (passthrough) {
3570 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3571 		    type, rid, res));
3572 	}
3573 
3574 	rle = resource_list_find(rl, type, rid);
3575 
3576 	if (!rle)
3577 		panic("resource_list_release: can't find resource");
3578 	if (!rle->res)
3579 		panic("resource_list_release: resource entry is not busy");
3580 	if (rle->flags & RLE_RESERVED) {
3581 		if (rle->flags & RLE_ALLOCATED) {
3582 			if (rman_get_flags(res) & RF_ACTIVE) {
3583 				error = bus_deactivate_resource(child, type,
3584 				    rid, res);
3585 				if (error)
3586 					return (error);
3587 			}
3588 			rle->flags &= ~RLE_ALLOCATED;
3589 			return (0);
3590 		}
3591 		return (EINVAL);
3592 	}
3593 
3594 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3595 	    type, rid, res);
3596 	if (error)
3597 		return (error);
3598 
3599 	rle->res = NULL;
3600 	return (0);
3601 }
3602 
3603 /**
3604  * @brief Release all active resources of a given type
3605  *
3606  * Release all active resources of a specified type.  This is intended
3607  * to be used to cleanup resources leaked by a driver after detach or
3608  * a failed attach.
3609  *
3610  * @param rl		the resource list which was allocated from
3611  * @param bus		the parent device of @p child
3612  * @param child		the device whose active resources are being released
3613  * @param type		the type of resources to release
3614  *
3615  * @retval 0		success
3616  * @retval EBUSY	at least one resource was active
3617  */
3618 int
3619 resource_list_release_active(struct resource_list *rl, device_t bus,
3620     device_t child, int type)
3621 {
3622 	struct resource_list_entry *rle;
3623 	int error, retval;
3624 
3625 	retval = 0;
3626 	STAILQ_FOREACH(rle, rl, link) {
3627 		if (rle->type != type)
3628 			continue;
3629 		if (rle->res == NULL)
3630 			continue;
3631 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3632 		    RLE_RESERVED)
3633 			continue;
3634 		retval = EBUSY;
3635 		error = resource_list_release(rl, bus, child, type,
3636 		    rman_get_rid(rle->res), rle->res);
3637 		if (error != 0)
3638 			device_printf(bus,
3639 			    "Failed to release active resource: %d\n", error);
3640 	}
3641 	return (retval);
3642 }
3643 
3644 /**
3645  * @brief Fully release a reserved resource
3646  *
3647  * Fully releases a resource reserved via resource_list_reserve().
3648  *
3649  * @param rl		the resource list which was allocated from
3650  * @param bus		the parent device of @p child
3651  * @param child		the device whose reserved resource is being released
3652  * @param type		the type of resource to release
3653  * @param rid		the resource identifier
3654  * @param res		the resource to release
3655  *
3656  * @retval 0		success
3657  * @retval non-zero	a standard unix error code indicating what
3658  *			error condition prevented the operation
3659  */
3660 int
3661 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3662     int type, int rid)
3663 {
3664 	struct resource_list_entry *rle = NULL;
3665 	int passthrough = (device_get_parent(child) != bus);
3666 
3667 	if (passthrough)
3668 		panic(
3669     "resource_list_unreserve() should only be called for direct children");
3670 
3671 	rle = resource_list_find(rl, type, rid);
3672 
3673 	if (!rle)
3674 		panic("resource_list_unreserve: can't find resource");
3675 	if (!(rle->flags & RLE_RESERVED))
3676 		return (EINVAL);
3677 	if (rle->flags & RLE_ALLOCATED)
3678 		return (EBUSY);
3679 	rle->flags &= ~RLE_RESERVED;
3680 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3681 }
3682 
3683 /**
3684  * @brief Print a description of resources in a resource list
3685  *
3686  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3687  * The name is printed if at least one resource of the given type is available.
3688  * The format is used to print resource start and end.
3689  *
3690  * @param rl		the resource list to print
3691  * @param name		the name of @p type, e.g. @c "memory"
3692  * @param type		type type of resource entry to print
3693  * @param format	printf(9) format string to print resource
3694  *			start and end values
3695  *
3696  * @returns		the number of characters printed
3697  */
3698 int
3699 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3700     const char *format)
3701 {
3702 	struct resource_list_entry *rle;
3703 	int printed, retval;
3704 
3705 	printed = 0;
3706 	retval = 0;
3707 	/* Yes, this is kinda cheating */
3708 	STAILQ_FOREACH(rle, rl, link) {
3709 		if (rle->type == type) {
3710 			if (printed == 0)
3711 				retval += printf(" %s ", name);
3712 			else
3713 				retval += printf(",");
3714 			printed++;
3715 			retval += printf(format, rle->start);
3716 			if (rle->count > 1) {
3717 				retval += printf("-");
3718 				retval += printf(format, rle->start +
3719 						 rle->count - 1);
3720 			}
3721 		}
3722 	}
3723 	return (retval);
3724 }
3725 
3726 /**
3727  * @brief Releases all the resources in a list.
3728  *
3729  * @param rl		The resource list to purge.
3730  *
3731  * @returns		nothing
3732  */
3733 void
3734 resource_list_purge(struct resource_list *rl)
3735 {
3736 	struct resource_list_entry *rle;
3737 
3738 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3739 		if (rle->res)
3740 			bus_release_resource(rman_get_device(rle->res),
3741 			    rle->type, rle->rid, rle->res);
3742 		STAILQ_REMOVE_HEAD(rl, link);
3743 		free(rle, M_BUS);
3744 	}
3745 }
3746 
3747 device_t
3748 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3749 {
3750 	return (device_add_child_ordered(dev, order, name, unit));
3751 }
3752 
3753 /**
3754  * @brief Helper function for implementing DEVICE_PROBE()
3755  *
3756  * This function can be used to help implement the DEVICE_PROBE() for
3757  * a bus (i.e. a device which has other devices attached to it). It
3758  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3759  * devclass.
3760  */
3761 int
3762 bus_generic_probe(device_t dev)
3763 {
3764 	devclass_t dc = dev->devclass;
3765 	driverlink_t dl;
3766 
3767 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3768 		/*
3769 		 * If this driver's pass is too high, then ignore it.
3770 		 * For most drivers in the default pass, this will
3771 		 * never be true.  For early-pass drivers they will
3772 		 * only call the identify routines of eligible drivers
3773 		 * when this routine is called.  Drivers for later
3774 		 * passes should have their identify routines called
3775 		 * on early-pass buses during BUS_NEW_PASS().
3776 		 */
3777 		if (dl->pass > bus_current_pass)
3778 			continue;
3779 		DEVICE_IDENTIFY(dl->driver, dev);
3780 	}
3781 
3782 	return (0);
3783 }
3784 
3785 /**
3786  * @brief Helper function for implementing DEVICE_ATTACH()
3787  *
3788  * This function can be used to help implement the DEVICE_ATTACH() for
3789  * a bus. It calls device_probe_and_attach() for each of the device's
3790  * children.
3791  */
3792 int
3793 bus_generic_attach(device_t dev)
3794 {
3795 	device_t child;
3796 
3797 	TAILQ_FOREACH(child, &dev->children, link) {
3798 		device_probe_and_attach(child);
3799 	}
3800 
3801 	return (0);
3802 }
3803 
3804 /**
3805  * @brief Helper function for delaying attaching children
3806  *
3807  * Many buses can't run transactions on the bus which children need to probe and
3808  * attach until after interrupts and/or timers are running.  This function
3809  * delays their attach until interrupts and timers are enabled.
3810  */
3811 int
3812 bus_delayed_attach_children(device_t dev)
3813 {
3814 	/* Probe and attach the bus children when interrupts are available */
3815 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3816 
3817 	return (0);
3818 }
3819 
3820 /**
3821  * @brief Helper function for implementing DEVICE_DETACH()
3822  *
3823  * This function can be used to help implement the DEVICE_DETACH() for
3824  * a bus. It calls device_detach() for each of the device's
3825  * children.
3826  */
3827 int
3828 bus_generic_detach(device_t dev)
3829 {
3830 	device_t child;
3831 	int error;
3832 
3833 	if (dev->state != DS_ATTACHED)
3834 		return (EBUSY);
3835 
3836 	/*
3837 	 * Detach children in the reverse order.
3838 	 * See bus_generic_suspend for details.
3839 	 */
3840 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3841 		if ((error = device_detach(child)) != 0)
3842 			return (error);
3843 	}
3844 
3845 	return (0);
3846 }
3847 
3848 /**
3849  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3850  *
3851  * This function can be used to help implement the DEVICE_SHUTDOWN()
3852  * for a bus. It calls device_shutdown() for each of the device's
3853  * children.
3854  */
3855 int
3856 bus_generic_shutdown(device_t dev)
3857 {
3858 	device_t child;
3859 
3860 	/*
3861 	 * Shut down children in the reverse order.
3862 	 * See bus_generic_suspend for details.
3863 	 */
3864 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3865 		device_shutdown(child);
3866 	}
3867 
3868 	return (0);
3869 }
3870 
3871 /**
3872  * @brief Default function for suspending a child device.
3873  *
3874  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3875  */
3876 int
3877 bus_generic_suspend_child(device_t dev, device_t child)
3878 {
3879 	int	error;
3880 
3881 	error = DEVICE_SUSPEND(child);
3882 
3883 	if (error == 0)
3884 		child->flags |= DF_SUSPENDED;
3885 
3886 	return (error);
3887 }
3888 
3889 /**
3890  * @brief Default function for resuming a child device.
3891  *
3892  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3893  */
3894 int
3895 bus_generic_resume_child(device_t dev, device_t child)
3896 {
3897 	DEVICE_RESUME(child);
3898 	child->flags &= ~DF_SUSPENDED;
3899 
3900 	return (0);
3901 }
3902 
3903 /**
3904  * @brief Helper function for implementing DEVICE_SUSPEND()
3905  *
3906  * This function can be used to help implement the DEVICE_SUSPEND()
3907  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3908  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3909  * operation is aborted and any devices which were suspended are
3910  * resumed immediately by calling their DEVICE_RESUME() methods.
3911  */
3912 int
3913 bus_generic_suspend(device_t dev)
3914 {
3915 	int		error;
3916 	device_t	child;
3917 
3918 	/*
3919 	 * Suspend children in the reverse order.
3920 	 * For most buses all children are equal, so the order does not matter.
3921 	 * Other buses, such as acpi, carefully order their child devices to
3922 	 * express implicit dependencies between them.  For such buses it is
3923 	 * safer to bring down devices in the reverse order.
3924 	 */
3925 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3926 		error = BUS_SUSPEND_CHILD(dev, child);
3927 		if (error != 0) {
3928 			child = TAILQ_NEXT(child, link);
3929 			if (child != NULL) {
3930 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3931 					BUS_RESUME_CHILD(dev, child);
3932 			}
3933 			return (error);
3934 		}
3935 	}
3936 	return (0);
3937 }
3938 
3939 /**
3940  * @brief Helper function for implementing DEVICE_RESUME()
3941  *
3942  * This function can be used to help implement the DEVICE_RESUME() for
3943  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3944  */
3945 int
3946 bus_generic_resume(device_t dev)
3947 {
3948 	device_t	child;
3949 
3950 	TAILQ_FOREACH(child, &dev->children, link) {
3951 		BUS_RESUME_CHILD(dev, child);
3952 		/* if resume fails, there's nothing we can usefully do... */
3953 	}
3954 	return (0);
3955 }
3956 
3957 /**
3958  * @brief Helper function for implementing BUS_RESET_POST
3959  *
3960  * Bus can use this function to implement common operations of
3961  * re-attaching or resuming the children after the bus itself was
3962  * reset, and after restoring bus-unique state of children.
3963  *
3964  * @param dev	The bus
3965  * #param flags	DEVF_RESET_*
3966  */
3967 int
3968 bus_helper_reset_post(device_t dev, int flags)
3969 {
3970 	device_t child;
3971 	int error, error1;
3972 
3973 	error = 0;
3974 	TAILQ_FOREACH(child, &dev->children,link) {
3975 		BUS_RESET_POST(dev, child);
3976 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3977 		    device_probe_and_attach(child) :
3978 		    BUS_RESUME_CHILD(dev, child);
3979 		if (error == 0 && error1 != 0)
3980 			error = error1;
3981 	}
3982 	return (error);
3983 }
3984 
3985 static void
3986 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3987 {
3988 	child = TAILQ_NEXT(child, link);
3989 	if (child == NULL)
3990 		return;
3991 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3992 		BUS_RESET_POST(dev, child);
3993 		if ((flags & DEVF_RESET_DETACH) != 0)
3994 			device_probe_and_attach(child);
3995 		else
3996 			BUS_RESUME_CHILD(dev, child);
3997 	}
3998 }
3999 
4000 /**
4001  * @brief Helper function for implementing BUS_RESET_PREPARE
4002  *
4003  * Bus can use this function to implement common operations of
4004  * detaching or suspending the children before the bus itself is
4005  * reset, and then save bus-unique state of children that must
4006  * persists around reset.
4007  *
4008  * @param dev	The bus
4009  * #param flags	DEVF_RESET_*
4010  */
4011 int
4012 bus_helper_reset_prepare(device_t dev, int flags)
4013 {
4014 	device_t child;
4015 	int error;
4016 
4017 	if (dev->state != DS_ATTACHED)
4018 		return (EBUSY);
4019 
4020 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
4021 		if ((flags & DEVF_RESET_DETACH) != 0) {
4022 			error = device_get_state(child) == DS_ATTACHED ?
4023 			    device_detach(child) : 0;
4024 		} else {
4025 			error = BUS_SUSPEND_CHILD(dev, child);
4026 		}
4027 		if (error == 0) {
4028 			error = BUS_RESET_PREPARE(dev, child);
4029 			if (error != 0) {
4030 				if ((flags & DEVF_RESET_DETACH) != 0)
4031 					device_probe_and_attach(child);
4032 				else
4033 					BUS_RESUME_CHILD(dev, child);
4034 			}
4035 		}
4036 		if (error != 0) {
4037 			bus_helper_reset_prepare_rollback(dev, child, flags);
4038 			return (error);
4039 		}
4040 	}
4041 	return (0);
4042 }
4043 
4044 /**
4045  * @brief Helper function for implementing BUS_PRINT_CHILD().
4046  *
4047  * This function prints the first part of the ascii representation of
4048  * @p child, including its name, unit and description (if any - see
4049  * device_set_desc()).
4050  *
4051  * @returns the number of characters printed
4052  */
4053 int
4054 bus_print_child_header(device_t dev, device_t child)
4055 {
4056 	int	retval = 0;
4057 
4058 	if (device_get_desc(child)) {
4059 		retval += device_printf(child, "<%s>", device_get_desc(child));
4060 	} else {
4061 		retval += printf("%s", device_get_nameunit(child));
4062 	}
4063 
4064 	return (retval);
4065 }
4066 
4067 /**
4068  * @brief Helper function for implementing BUS_PRINT_CHILD().
4069  *
4070  * This function prints the last part of the ascii representation of
4071  * @p child, which consists of the string @c " on " followed by the
4072  * name and unit of the @p dev.
4073  *
4074  * @returns the number of characters printed
4075  */
4076 int
4077 bus_print_child_footer(device_t dev, device_t child)
4078 {
4079 	return (printf(" on %s\n", device_get_nameunit(dev)));
4080 }
4081 
4082 /**
4083  * @brief Helper function for implementing BUS_PRINT_CHILD().
4084  *
4085  * This function prints out the VM domain for the given device.
4086  *
4087  * @returns the number of characters printed
4088  */
4089 int
4090 bus_print_child_domain(device_t dev, device_t child)
4091 {
4092 	int domain;
4093 
4094 	/* No domain? Don't print anything */
4095 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4096 		return (0);
4097 
4098 	return (printf(" numa-domain %d", domain));
4099 }
4100 
4101 /**
4102  * @brief Helper function for implementing BUS_PRINT_CHILD().
4103  *
4104  * This function simply calls bus_print_child_header() followed by
4105  * bus_print_child_footer().
4106  *
4107  * @returns the number of characters printed
4108  */
4109 int
4110 bus_generic_print_child(device_t dev, device_t child)
4111 {
4112 	int	retval = 0;
4113 
4114 	retval += bus_print_child_header(dev, child);
4115 	retval += bus_print_child_domain(dev, child);
4116 	retval += bus_print_child_footer(dev, child);
4117 
4118 	return (retval);
4119 }
4120 
4121 /**
4122  * @brief Stub function for implementing BUS_READ_IVAR().
4123  *
4124  * @returns ENOENT
4125  */
4126 int
4127 bus_generic_read_ivar(device_t dev, device_t child, int index,
4128     uintptr_t * result)
4129 {
4130 	return (ENOENT);
4131 }
4132 
4133 /**
4134  * @brief Stub function for implementing BUS_WRITE_IVAR().
4135  *
4136  * @returns ENOENT
4137  */
4138 int
4139 bus_generic_write_ivar(device_t dev, device_t child, int index,
4140     uintptr_t value)
4141 {
4142 	return (ENOENT);
4143 }
4144 
4145 /**
4146  * @brief Helper function for implementing BUS_GET_PROPERTY().
4147  *
4148  * This simply calls the BUS_GET_PROPERTY of the parent of dev,
4149  * until a non-default implementation is found.
4150  */
4151 ssize_t
4152 bus_generic_get_property(device_t dev, device_t child, const char *propname,
4153     void *propvalue, size_t size, device_property_type_t type)
4154 {
4155 	if (device_get_parent(dev) != NULL)
4156 		return (BUS_GET_PROPERTY(device_get_parent(dev), child,
4157 		    propname, propvalue, size, type));
4158 
4159 	return (-1);
4160 }
4161 
4162 /**
4163  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4164  *
4165  * @returns NULL
4166  */
4167 struct resource_list *
4168 bus_generic_get_resource_list(device_t dev, device_t child)
4169 {
4170 	return (NULL);
4171 }
4172 
4173 /**
4174  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4175  *
4176  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4177  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4178  * and then calls device_probe_and_attach() for each unattached child.
4179  */
4180 void
4181 bus_generic_driver_added(device_t dev, driver_t *driver)
4182 {
4183 	device_t child;
4184 
4185 	DEVICE_IDENTIFY(driver, dev);
4186 	TAILQ_FOREACH(child, &dev->children, link) {
4187 		if (child->state == DS_NOTPRESENT)
4188 			device_probe_and_attach(child);
4189 	}
4190 }
4191 
4192 /**
4193  * @brief Helper function for implementing BUS_NEW_PASS().
4194  *
4195  * This implementing of BUS_NEW_PASS() first calls the identify
4196  * routines for any drivers that probe at the current pass.  Then it
4197  * walks the list of devices for this bus.  If a device is already
4198  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4199  * device is not already attached, it attempts to attach a driver to
4200  * it.
4201  */
4202 void
4203 bus_generic_new_pass(device_t dev)
4204 {
4205 	driverlink_t dl;
4206 	devclass_t dc;
4207 	device_t child;
4208 
4209 	dc = dev->devclass;
4210 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4211 		if (dl->pass == bus_current_pass)
4212 			DEVICE_IDENTIFY(dl->driver, dev);
4213 	}
4214 	TAILQ_FOREACH(child, &dev->children, link) {
4215 		if (child->state >= DS_ATTACHED)
4216 			BUS_NEW_PASS(child);
4217 		else if (child->state == DS_NOTPRESENT)
4218 			device_probe_and_attach(child);
4219 	}
4220 }
4221 
4222 /**
4223  * @brief Helper function for implementing BUS_SETUP_INTR().
4224  *
4225  * This simple implementation of BUS_SETUP_INTR() simply calls the
4226  * BUS_SETUP_INTR() method of the parent of @p dev.
4227  */
4228 int
4229 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4230     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4231     void **cookiep)
4232 {
4233 	/* Propagate up the bus hierarchy until someone handles it. */
4234 	if (dev->parent)
4235 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4236 		    filter, intr, arg, cookiep));
4237 	return (EINVAL);
4238 }
4239 
4240 /**
4241  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4242  *
4243  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4244  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4245  */
4246 int
4247 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4248     void *cookie)
4249 {
4250 	/* Propagate up the bus hierarchy until someone handles it. */
4251 	if (dev->parent)
4252 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4253 	return (EINVAL);
4254 }
4255 
4256 /**
4257  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4258  *
4259  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4260  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4261  */
4262 int
4263 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4264 {
4265 	/* Propagate up the bus hierarchy until someone handles it. */
4266 	if (dev->parent)
4267 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4268 	return (EINVAL);
4269 }
4270 
4271 /**
4272  * @brief Helper function for implementing BUS_RESUME_INTR().
4273  *
4274  * This simple implementation of BUS_RESUME_INTR() simply calls the
4275  * BUS_RESUME_INTR() method of the parent of @p dev.
4276  */
4277 int
4278 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4279 {
4280 	/* Propagate up the bus hierarchy until someone handles it. */
4281 	if (dev->parent)
4282 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4283 	return (EINVAL);
4284 }
4285 
4286 /**
4287  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4288  *
4289  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4290  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4291  */
4292 int
4293 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4294     struct resource *r, rman_res_t start, rman_res_t end)
4295 {
4296 	/* Propagate up the bus hierarchy until someone handles it. */
4297 	if (dev->parent)
4298 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4299 		    end));
4300 	return (EINVAL);
4301 }
4302 
4303 /*
4304  * @brief Helper function for implementing BUS_TRANSLATE_RESOURCE().
4305  *
4306  * This simple implementation of BUS_TRANSLATE_RESOURCE() simply calls the
4307  * BUS_TRANSLATE_RESOURCE() method of the parent of @p dev.  If there is no
4308  * parent, no translation happens.
4309  */
4310 int
4311 bus_generic_translate_resource(device_t dev, int type, rman_res_t start,
4312     rman_res_t *newstart)
4313 {
4314 	if (dev->parent)
4315 		return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start,
4316 		    newstart));
4317 	*newstart = start;
4318 	return (0);
4319 }
4320 
4321 /**
4322  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4323  *
4324  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4325  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4326  */
4327 struct resource *
4328 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4329     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4330 {
4331 	/* Propagate up the bus hierarchy until someone handles it. */
4332 	if (dev->parent)
4333 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4334 		    start, end, count, flags));
4335 	return (NULL);
4336 }
4337 
4338 /**
4339  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4340  *
4341  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4342  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4343  */
4344 int
4345 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4346     struct resource *r)
4347 {
4348 	/* Propagate up the bus hierarchy until someone handles it. */
4349 	if (dev->parent)
4350 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4351 		    r));
4352 	return (EINVAL);
4353 }
4354 
4355 /**
4356  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4357  *
4358  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4359  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4360  */
4361 int
4362 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4363     struct resource *r)
4364 {
4365 	/* Propagate up the bus hierarchy until someone handles it. */
4366 	if (dev->parent)
4367 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4368 		    r));
4369 	return (EINVAL);
4370 }
4371 
4372 /**
4373  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4374  *
4375  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4376  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4377  */
4378 int
4379 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4380     int rid, struct resource *r)
4381 {
4382 	/* Propagate up the bus hierarchy until someone handles it. */
4383 	if (dev->parent)
4384 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4385 		    r));
4386 	return (EINVAL);
4387 }
4388 
4389 /**
4390  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4391  *
4392  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4393  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4394  */
4395 int
4396 bus_generic_map_resource(device_t dev, device_t child, int type,
4397     struct resource *r, struct resource_map_request *args,
4398     struct resource_map *map)
4399 {
4400 	/* Propagate up the bus hierarchy until someone handles it. */
4401 	if (dev->parent)
4402 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4403 		    map));
4404 	return (EINVAL);
4405 }
4406 
4407 /**
4408  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4409  *
4410  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4411  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4412  */
4413 int
4414 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4415     struct resource *r, struct resource_map *map)
4416 {
4417 	/* Propagate up the bus hierarchy until someone handles it. */
4418 	if (dev->parent)
4419 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4420 	return (EINVAL);
4421 }
4422 
4423 /**
4424  * @brief Helper function for implementing BUS_BIND_INTR().
4425  *
4426  * This simple implementation of BUS_BIND_INTR() simply calls the
4427  * BUS_BIND_INTR() method of the parent of @p dev.
4428  */
4429 int
4430 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4431     int cpu)
4432 {
4433 	/* Propagate up the bus hierarchy until someone handles it. */
4434 	if (dev->parent)
4435 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4436 	return (EINVAL);
4437 }
4438 
4439 /**
4440  * @brief Helper function for implementing BUS_CONFIG_INTR().
4441  *
4442  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4443  * BUS_CONFIG_INTR() method of the parent of @p dev.
4444  */
4445 int
4446 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4447     enum intr_polarity pol)
4448 {
4449 	/* Propagate up the bus hierarchy until someone handles it. */
4450 	if (dev->parent)
4451 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4452 	return (EINVAL);
4453 }
4454 
4455 /**
4456  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4457  *
4458  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4459  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4460  */
4461 int
4462 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4463     void *cookie, const char *descr)
4464 {
4465 	/* Propagate up the bus hierarchy until someone handles it. */
4466 	if (dev->parent)
4467 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4468 		    descr));
4469 	return (EINVAL);
4470 }
4471 
4472 /**
4473  * @brief Helper function for implementing BUS_GET_CPUS().
4474  *
4475  * This simple implementation of BUS_GET_CPUS() simply calls the
4476  * BUS_GET_CPUS() method of the parent of @p dev.
4477  */
4478 int
4479 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4480     size_t setsize, cpuset_t *cpuset)
4481 {
4482 	/* Propagate up the bus hierarchy until someone handles it. */
4483 	if (dev->parent != NULL)
4484 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4485 	return (EINVAL);
4486 }
4487 
4488 /**
4489  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4490  *
4491  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4492  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4493  */
4494 bus_dma_tag_t
4495 bus_generic_get_dma_tag(device_t dev, device_t child)
4496 {
4497 	/* Propagate up the bus hierarchy until someone handles it. */
4498 	if (dev->parent != NULL)
4499 		return (BUS_GET_DMA_TAG(dev->parent, child));
4500 	return (NULL);
4501 }
4502 
4503 /**
4504  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4505  *
4506  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4507  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4508  */
4509 bus_space_tag_t
4510 bus_generic_get_bus_tag(device_t dev, device_t child)
4511 {
4512 	/* Propagate up the bus hierarchy until someone handles it. */
4513 	if (dev->parent != NULL)
4514 		return (BUS_GET_BUS_TAG(dev->parent, child));
4515 	return ((bus_space_tag_t)0);
4516 }
4517 
4518 /**
4519  * @brief Helper function for implementing BUS_GET_RESOURCE().
4520  *
4521  * This implementation of BUS_GET_RESOURCE() uses the
4522  * resource_list_find() function to do most of the work. It calls
4523  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4524  * search.
4525  */
4526 int
4527 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4528     rman_res_t *startp, rman_res_t *countp)
4529 {
4530 	struct resource_list *		rl = NULL;
4531 	struct resource_list_entry *	rle = NULL;
4532 
4533 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4534 	if (!rl)
4535 		return (EINVAL);
4536 
4537 	rle = resource_list_find(rl, type, rid);
4538 	if (!rle)
4539 		return (ENOENT);
4540 
4541 	if (startp)
4542 		*startp = rle->start;
4543 	if (countp)
4544 		*countp = rle->count;
4545 
4546 	return (0);
4547 }
4548 
4549 /**
4550  * @brief Helper function for implementing BUS_SET_RESOURCE().
4551  *
4552  * This implementation of BUS_SET_RESOURCE() uses the
4553  * resource_list_add() function to do most of the work. It calls
4554  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4555  * edit.
4556  */
4557 int
4558 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4559     rman_res_t start, rman_res_t count)
4560 {
4561 	struct resource_list *		rl = NULL;
4562 
4563 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4564 	if (!rl)
4565 		return (EINVAL);
4566 
4567 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4568 
4569 	return (0);
4570 }
4571 
4572 /**
4573  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4574  *
4575  * This implementation of BUS_DELETE_RESOURCE() uses the
4576  * resource_list_delete() function to do most of the work. It calls
4577  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4578  * edit.
4579  */
4580 void
4581 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4582 {
4583 	struct resource_list *		rl = NULL;
4584 
4585 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4586 	if (!rl)
4587 		return;
4588 
4589 	resource_list_delete(rl, type, rid);
4590 
4591 	return;
4592 }
4593 
4594 /**
4595  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4596  *
4597  * This implementation of BUS_RELEASE_RESOURCE() uses the
4598  * resource_list_release() function to do most of the work. It calls
4599  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4600  */
4601 int
4602 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4603     int rid, struct resource *r)
4604 {
4605 	struct resource_list *		rl = NULL;
4606 
4607 	if (device_get_parent(child) != dev)
4608 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4609 		    type, rid, r));
4610 
4611 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4612 	if (!rl)
4613 		return (EINVAL);
4614 
4615 	return (resource_list_release(rl, dev, child, type, rid, r));
4616 }
4617 
4618 /**
4619  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4620  *
4621  * This implementation of BUS_ALLOC_RESOURCE() uses the
4622  * resource_list_alloc() function to do most of the work. It calls
4623  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4624  */
4625 struct resource *
4626 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4627     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4628 {
4629 	struct resource_list *		rl = NULL;
4630 
4631 	if (device_get_parent(child) != dev)
4632 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4633 		    type, rid, start, end, count, flags));
4634 
4635 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4636 	if (!rl)
4637 		return (NULL);
4638 
4639 	return (resource_list_alloc(rl, dev, child, type, rid,
4640 	    start, end, count, flags));
4641 }
4642 
4643 /**
4644  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4645  *
4646  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4647  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4648  */
4649 int
4650 bus_generic_child_present(device_t dev, device_t child)
4651 {
4652 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4653 }
4654 
4655 int
4656 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4657 {
4658 	if (dev->parent)
4659 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4660 
4661 	return (ENOENT);
4662 }
4663 
4664 /**
4665  * @brief Helper function to implement normal BUS_GET_DEVICE_PATH()
4666  *
4667  * This function knows how to (a) pass the request up the tree if there's
4668  * a parent and (b) Knows how to supply a FreeBSD locator.
4669  *
4670  * @param bus		bus in the walk up the tree
4671  * @param child		leaf node to print information about
4672  * @param locator	BUS_LOCATOR_xxx string for locator
4673  * @param sb		Buffer to print information into
4674  */
4675 int
4676 bus_generic_get_device_path(device_t bus, device_t child, const char *locator,
4677     struct sbuf *sb)
4678 {
4679 	int rv = 0;
4680 	device_t parent;
4681 
4682 	/*
4683 	 * We don't recurse on ACPI since either we know the handle for the
4684 	 * device or we don't. And if we're in the generic routine, we don't
4685 	 * have a ACPI override. All other locators build up a path by having
4686 	 * their parents create a path and then adding the path element for this
4687 	 * node. That's why we recurse with parent, bus rather than the typical
4688 	 * parent, child: each spot in the tree is independent of what our child
4689 	 * will do with this path.
4690 	 */
4691 	parent = device_get_parent(bus);
4692 	if (parent != NULL && strcmp(locator, BUS_LOCATOR_ACPI) != 0) {
4693 		rv = BUS_GET_DEVICE_PATH(parent, bus, locator, sb);
4694 	}
4695 	if (strcmp(locator, BUS_LOCATOR_FREEBSD) == 0) {
4696 		if (rv == 0) {
4697 			sbuf_printf(sb, "/%s", device_get_nameunit(child));
4698 		}
4699 		return (rv);
4700 	}
4701 	/*
4702 	 * Don't know what to do. So assume we do nothing. Not sure that's
4703 	 * the right thing, but keeps us from having a big list here.
4704 	 */
4705 	return (0);
4706 }
4707 
4708 
4709 /**
4710  * @brief Helper function for implementing BUS_RESCAN().
4711  *
4712  * This null implementation of BUS_RESCAN() always fails to indicate
4713  * the bus does not support rescanning.
4714  */
4715 int
4716 bus_null_rescan(device_t dev)
4717 {
4718 	return (ENXIO);
4719 }
4720 
4721 /*
4722  * Some convenience functions to make it easier for drivers to use the
4723  * resource-management functions.  All these really do is hide the
4724  * indirection through the parent's method table, making for slightly
4725  * less-wordy code.  In the future, it might make sense for this code
4726  * to maintain some sort of a list of resources allocated by each device.
4727  */
4728 
4729 int
4730 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4731     struct resource **res)
4732 {
4733 	int i;
4734 
4735 	for (i = 0; rs[i].type != -1; i++)
4736 		res[i] = NULL;
4737 	for (i = 0; rs[i].type != -1; i++) {
4738 		res[i] = bus_alloc_resource_any(dev,
4739 		    rs[i].type, &rs[i].rid, rs[i].flags);
4740 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4741 			bus_release_resources(dev, rs, res);
4742 			return (ENXIO);
4743 		}
4744 	}
4745 	return (0);
4746 }
4747 
4748 void
4749 bus_release_resources(device_t dev, const struct resource_spec *rs,
4750     struct resource **res)
4751 {
4752 	int i;
4753 
4754 	for (i = 0; rs[i].type != -1; i++)
4755 		if (res[i] != NULL) {
4756 			bus_release_resource(
4757 			    dev, rs[i].type, rs[i].rid, res[i]);
4758 			res[i] = NULL;
4759 		}
4760 }
4761 
4762 /**
4763  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4764  *
4765  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4766  * parent of @p dev.
4767  */
4768 struct resource *
4769 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4770     rman_res_t end, rman_res_t count, u_int flags)
4771 {
4772 	struct resource *res;
4773 
4774 	if (dev->parent == NULL)
4775 		return (NULL);
4776 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4777 	    count, flags);
4778 	return (res);
4779 }
4780 
4781 /**
4782  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4783  *
4784  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4785  * parent of @p dev.
4786  */
4787 int
4788 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4789     rman_res_t end)
4790 {
4791 	if (dev->parent == NULL)
4792 		return (EINVAL);
4793 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4794 }
4795 
4796 /**
4797  * @brief Wrapper function for BUS_TRANSLATE_RESOURCE().
4798  *
4799  * This function simply calls the BUS_TRANSLATE_RESOURCE() method of the
4800  * parent of @p dev.
4801  */
4802 int
4803 bus_translate_resource(device_t dev, int type, rman_res_t start,
4804     rman_res_t *newstart)
4805 {
4806 	if (dev->parent == NULL)
4807 		return (EINVAL);
4808 	return (BUS_TRANSLATE_RESOURCE(dev->parent, type, start, newstart));
4809 }
4810 
4811 /**
4812  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4813  *
4814  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4815  * parent of @p dev.
4816  */
4817 int
4818 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4819 {
4820 	if (dev->parent == NULL)
4821 		return (EINVAL);
4822 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4823 }
4824 
4825 /**
4826  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4827  *
4828  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4829  * parent of @p dev.
4830  */
4831 int
4832 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4833 {
4834 	if (dev->parent == NULL)
4835 		return (EINVAL);
4836 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4837 }
4838 
4839 /**
4840  * @brief Wrapper function for BUS_MAP_RESOURCE().
4841  *
4842  * This function simply calls the BUS_MAP_RESOURCE() method of the
4843  * parent of @p dev.
4844  */
4845 int
4846 bus_map_resource(device_t dev, int type, struct resource *r,
4847     struct resource_map_request *args, struct resource_map *map)
4848 {
4849 	if (dev->parent == NULL)
4850 		return (EINVAL);
4851 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4852 }
4853 
4854 /**
4855  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4856  *
4857  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4858  * parent of @p dev.
4859  */
4860 int
4861 bus_unmap_resource(device_t dev, int type, struct resource *r,
4862     struct resource_map *map)
4863 {
4864 	if (dev->parent == NULL)
4865 		return (EINVAL);
4866 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4867 }
4868 
4869 /**
4870  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4871  *
4872  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4873  * parent of @p dev.
4874  */
4875 int
4876 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4877 {
4878 	int rv;
4879 
4880 	if (dev->parent == NULL)
4881 		return (EINVAL);
4882 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4883 	return (rv);
4884 }
4885 
4886 /**
4887  * @brief Wrapper function for BUS_SETUP_INTR().
4888  *
4889  * This function simply calls the BUS_SETUP_INTR() method of the
4890  * parent of @p dev.
4891  */
4892 int
4893 bus_setup_intr(device_t dev, struct resource *r, int flags,
4894     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4895 {
4896 	int error;
4897 
4898 	if (dev->parent == NULL)
4899 		return (EINVAL);
4900 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4901 	    arg, cookiep);
4902 	if (error != 0)
4903 		return (error);
4904 	if (handler != NULL && !(flags & INTR_MPSAFE))
4905 		device_printf(dev, "[GIANT-LOCKED]\n");
4906 	return (0);
4907 }
4908 
4909 /**
4910  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4911  *
4912  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4913  * parent of @p dev.
4914  */
4915 int
4916 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4917 {
4918 	if (dev->parent == NULL)
4919 		return (EINVAL);
4920 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4921 }
4922 
4923 /**
4924  * @brief Wrapper function for BUS_SUSPEND_INTR().
4925  *
4926  * This function simply calls the BUS_SUSPEND_INTR() method of the
4927  * parent of @p dev.
4928  */
4929 int
4930 bus_suspend_intr(device_t dev, struct resource *r)
4931 {
4932 	if (dev->parent == NULL)
4933 		return (EINVAL);
4934 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4935 }
4936 
4937 /**
4938  * @brief Wrapper function for BUS_RESUME_INTR().
4939  *
4940  * This function simply calls the BUS_RESUME_INTR() method of the
4941  * parent of @p dev.
4942  */
4943 int
4944 bus_resume_intr(device_t dev, struct resource *r)
4945 {
4946 	if (dev->parent == NULL)
4947 		return (EINVAL);
4948 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4949 }
4950 
4951 /**
4952  * @brief Wrapper function for BUS_BIND_INTR().
4953  *
4954  * This function simply calls the BUS_BIND_INTR() method of the
4955  * parent of @p dev.
4956  */
4957 int
4958 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4959 {
4960 	if (dev->parent == NULL)
4961 		return (EINVAL);
4962 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4963 }
4964 
4965 /**
4966  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4967  *
4968  * This function first formats the requested description into a
4969  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4970  * the parent of @p dev.
4971  */
4972 int
4973 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4974     const char *fmt, ...)
4975 {
4976 	va_list ap;
4977 	char descr[MAXCOMLEN + 1];
4978 
4979 	if (dev->parent == NULL)
4980 		return (EINVAL);
4981 	va_start(ap, fmt);
4982 	vsnprintf(descr, sizeof(descr), fmt, ap);
4983 	va_end(ap);
4984 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4985 }
4986 
4987 /**
4988  * @brief Wrapper function for BUS_SET_RESOURCE().
4989  *
4990  * This function simply calls the BUS_SET_RESOURCE() method of the
4991  * parent of @p dev.
4992  */
4993 int
4994 bus_set_resource(device_t dev, int type, int rid,
4995     rman_res_t start, rman_res_t count)
4996 {
4997 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4998 	    start, count));
4999 }
5000 
5001 /**
5002  * @brief Wrapper function for BUS_GET_RESOURCE().
5003  *
5004  * This function simply calls the BUS_GET_RESOURCE() method of the
5005  * parent of @p dev.
5006  */
5007 int
5008 bus_get_resource(device_t dev, int type, int rid,
5009     rman_res_t *startp, rman_res_t *countp)
5010 {
5011 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5012 	    startp, countp));
5013 }
5014 
5015 /**
5016  * @brief Wrapper function for BUS_GET_RESOURCE().
5017  *
5018  * This function simply calls the BUS_GET_RESOURCE() method of the
5019  * parent of @p dev and returns the start value.
5020  */
5021 rman_res_t
5022 bus_get_resource_start(device_t dev, int type, int rid)
5023 {
5024 	rman_res_t start;
5025 	rman_res_t count;
5026 	int error;
5027 
5028 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5029 	    &start, &count);
5030 	if (error)
5031 		return (0);
5032 	return (start);
5033 }
5034 
5035 /**
5036  * @brief Wrapper function for BUS_GET_RESOURCE().
5037  *
5038  * This function simply calls the BUS_GET_RESOURCE() method of the
5039  * parent of @p dev and returns the count value.
5040  */
5041 rman_res_t
5042 bus_get_resource_count(device_t dev, int type, int rid)
5043 {
5044 	rman_res_t start;
5045 	rman_res_t count;
5046 	int error;
5047 
5048 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
5049 	    &start, &count);
5050 	if (error)
5051 		return (0);
5052 	return (count);
5053 }
5054 
5055 /**
5056  * @brief Wrapper function for BUS_DELETE_RESOURCE().
5057  *
5058  * This function simply calls the BUS_DELETE_RESOURCE() method of the
5059  * parent of @p dev.
5060  */
5061 void
5062 bus_delete_resource(device_t dev, int type, int rid)
5063 {
5064 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
5065 }
5066 
5067 /**
5068  * @brief Wrapper function for BUS_CHILD_PRESENT().
5069  *
5070  * This function simply calls the BUS_CHILD_PRESENT() method of the
5071  * parent of @p dev.
5072  */
5073 int
5074 bus_child_present(device_t child)
5075 {
5076 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
5077 }
5078 
5079 /**
5080  * @brief Wrapper function for BUS_CHILD_PNPINFO().
5081  *
5082  * This function simply calls the BUS_CHILD_PNPINFO() method of the parent of @p
5083  * dev.
5084  */
5085 int
5086 bus_child_pnpinfo(device_t child, struct sbuf *sb)
5087 {
5088 	device_t parent;
5089 
5090 	parent = device_get_parent(child);
5091 	if (parent == NULL)
5092 		return (0);
5093 	return (BUS_CHILD_PNPINFO(parent, child, sb));
5094 }
5095 
5096 /**
5097  * @brief Generic implementation that does nothing for bus_child_pnpinfo
5098  *
5099  * This function has the right signature and returns 0 since the sbuf is passed
5100  * to us to append to.
5101  */
5102 int
5103 bus_generic_child_pnpinfo(device_t dev, device_t child, struct sbuf *sb)
5104 {
5105 	return (0);
5106 }
5107 
5108 /**
5109  * @brief Wrapper function for BUS_CHILD_LOCATION().
5110  *
5111  * This function simply calls the BUS_CHILD_LOCATION() method of the parent of
5112  * @p dev.
5113  */
5114 int
5115 bus_child_location(device_t child, struct sbuf *sb)
5116 {
5117 	device_t parent;
5118 
5119 	parent = device_get_parent(child);
5120 	if (parent == NULL)
5121 		return (0);
5122 	return (BUS_CHILD_LOCATION(parent, child, sb));
5123 }
5124 
5125 /**
5126  * @brief Generic implementation that does nothing for bus_child_location
5127  *
5128  * This function has the right signature and returns 0 since the sbuf is passed
5129  * to us to append to.
5130  */
5131 int
5132 bus_generic_child_location(device_t dev, device_t child, struct sbuf *sb)
5133 {
5134 	return (0);
5135 }
5136 
5137 /**
5138  * @brief Wrapper function for BUS_GET_CPUS().
5139  *
5140  * This function simply calls the BUS_GET_CPUS() method of the
5141  * parent of @p dev.
5142  */
5143 int
5144 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5145 {
5146 	device_t parent;
5147 
5148 	parent = device_get_parent(dev);
5149 	if (parent == NULL)
5150 		return (EINVAL);
5151 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5152 }
5153 
5154 /**
5155  * @brief Wrapper function for BUS_GET_DMA_TAG().
5156  *
5157  * This function simply calls the BUS_GET_DMA_TAG() method of the
5158  * parent of @p dev.
5159  */
5160 bus_dma_tag_t
5161 bus_get_dma_tag(device_t dev)
5162 {
5163 	device_t parent;
5164 
5165 	parent = device_get_parent(dev);
5166 	if (parent == NULL)
5167 		return (NULL);
5168 	return (BUS_GET_DMA_TAG(parent, dev));
5169 }
5170 
5171 /**
5172  * @brief Wrapper function for BUS_GET_BUS_TAG().
5173  *
5174  * This function simply calls the BUS_GET_BUS_TAG() method of the
5175  * parent of @p dev.
5176  */
5177 bus_space_tag_t
5178 bus_get_bus_tag(device_t dev)
5179 {
5180 	device_t parent;
5181 
5182 	parent = device_get_parent(dev);
5183 	if (parent == NULL)
5184 		return ((bus_space_tag_t)0);
5185 	return (BUS_GET_BUS_TAG(parent, dev));
5186 }
5187 
5188 /**
5189  * @brief Wrapper function for BUS_GET_DOMAIN().
5190  *
5191  * This function simply calls the BUS_GET_DOMAIN() method of the
5192  * parent of @p dev.
5193  */
5194 int
5195 bus_get_domain(device_t dev, int *domain)
5196 {
5197 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5198 }
5199 
5200 /* Resume all devices and then notify userland that we're up again. */
5201 static int
5202 root_resume(device_t dev)
5203 {
5204 	int error;
5205 
5206 	error = bus_generic_resume(dev);
5207 	if (error == 0) {
5208 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5209 		devctl_notify("kernel", "power", "resume", NULL);
5210 	}
5211 	return (error);
5212 }
5213 
5214 static int
5215 root_print_child(device_t dev, device_t child)
5216 {
5217 	int	retval = 0;
5218 
5219 	retval += bus_print_child_header(dev, child);
5220 	retval += printf("\n");
5221 
5222 	return (retval);
5223 }
5224 
5225 static int
5226 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5227     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5228 {
5229 	/*
5230 	 * If an interrupt mapping gets to here something bad has happened.
5231 	 */
5232 	panic("root_setup_intr");
5233 }
5234 
5235 /*
5236  * If we get here, assume that the device is permanent and really is
5237  * present in the system.  Removable bus drivers are expected to intercept
5238  * this call long before it gets here.  We return -1 so that drivers that
5239  * really care can check vs -1 or some ERRNO returned higher in the food
5240  * chain.
5241  */
5242 static int
5243 root_child_present(device_t dev, device_t child)
5244 {
5245 	return (-1);
5246 }
5247 
5248 static int
5249 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5250     cpuset_t *cpuset)
5251 {
5252 	switch (op) {
5253 	case INTR_CPUS:
5254 		/* Default to returning the set of all CPUs. */
5255 		if (setsize != sizeof(cpuset_t))
5256 			return (EINVAL);
5257 		*cpuset = all_cpus;
5258 		return (0);
5259 	default:
5260 		return (EINVAL);
5261 	}
5262 }
5263 
5264 static kobj_method_t root_methods[] = {
5265 	/* Device interface */
5266 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5267 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5268 	KOBJMETHOD(device_resume,	root_resume),
5269 
5270 	/* Bus interface */
5271 	KOBJMETHOD(bus_print_child,	root_print_child),
5272 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5273 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5274 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5275 	KOBJMETHOD(bus_child_present,	root_child_present),
5276 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5277 
5278 	KOBJMETHOD_END
5279 };
5280 
5281 static driver_t root_driver = {
5282 	"root",
5283 	root_methods,
5284 	1,			/* no softc */
5285 };
5286 
5287 device_t	root_bus;
5288 devclass_t	root_devclass;
5289 
5290 static int
5291 root_bus_module_handler(module_t mod, int what, void* arg)
5292 {
5293 	switch (what) {
5294 	case MOD_LOAD:
5295 		TAILQ_INIT(&bus_data_devices);
5296 		kobj_class_compile((kobj_class_t) &root_driver);
5297 		root_bus = make_device(NULL, "root", 0);
5298 		root_bus->desc = "System root bus";
5299 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5300 		root_bus->driver = &root_driver;
5301 		root_bus->state = DS_ATTACHED;
5302 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5303 		devinit();
5304 		return (0);
5305 
5306 	case MOD_SHUTDOWN:
5307 		device_shutdown(root_bus);
5308 		return (0);
5309 	default:
5310 		return (EOPNOTSUPP);
5311 	}
5312 
5313 	return (0);
5314 }
5315 
5316 static moduledata_t root_bus_mod = {
5317 	"rootbus",
5318 	root_bus_module_handler,
5319 	NULL
5320 };
5321 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5322 
5323 /**
5324  * @brief Automatically configure devices
5325  *
5326  * This function begins the autoconfiguration process by calling
5327  * device_probe_and_attach() for each child of the @c root0 device.
5328  */
5329 void
5330 root_bus_configure(void)
5331 {
5332 	PDEBUG(("."));
5333 
5334 	/* Eventually this will be split up, but this is sufficient for now. */
5335 	bus_set_pass(BUS_PASS_DEFAULT);
5336 }
5337 
5338 /**
5339  * @brief Module handler for registering device drivers
5340  *
5341  * This module handler is used to automatically register device
5342  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5343  * devclass_add_driver() for the driver described by the
5344  * driver_module_data structure pointed to by @p arg
5345  */
5346 int
5347 driver_module_handler(module_t mod, int what, void *arg)
5348 {
5349 	struct driver_module_data *dmd;
5350 	devclass_t bus_devclass;
5351 	kobj_class_t driver;
5352 	int error, pass;
5353 
5354 	dmd = (struct driver_module_data *)arg;
5355 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5356 	error = 0;
5357 
5358 	switch (what) {
5359 	case MOD_LOAD:
5360 		if (dmd->dmd_chainevh)
5361 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5362 
5363 		pass = dmd->dmd_pass;
5364 		driver = dmd->dmd_driver;
5365 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5366 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5367 		error = devclass_add_driver(bus_devclass, driver, pass,
5368 		    dmd->dmd_devclass);
5369 		break;
5370 
5371 	case MOD_UNLOAD:
5372 		PDEBUG(("Unloading module: driver %s from bus %s",
5373 		    DRIVERNAME(dmd->dmd_driver),
5374 		    dmd->dmd_busname));
5375 		error = devclass_delete_driver(bus_devclass,
5376 		    dmd->dmd_driver);
5377 
5378 		if (!error && dmd->dmd_chainevh)
5379 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5380 		break;
5381 	case MOD_QUIESCE:
5382 		PDEBUG(("Quiesce module: driver %s from bus %s",
5383 		    DRIVERNAME(dmd->dmd_driver),
5384 		    dmd->dmd_busname));
5385 		error = devclass_quiesce_driver(bus_devclass,
5386 		    dmd->dmd_driver);
5387 
5388 		if (!error && dmd->dmd_chainevh)
5389 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5390 		break;
5391 	default:
5392 		error = EOPNOTSUPP;
5393 		break;
5394 	}
5395 
5396 	return (error);
5397 }
5398 
5399 /**
5400  * @brief Enumerate all hinted devices for this bus.
5401  *
5402  * Walks through the hints for this bus and calls the bus_hinted_child
5403  * routine for each one it fines.  It searches first for the specific
5404  * bus that's being probed for hinted children (eg isa0), and then for
5405  * generic children (eg isa).
5406  *
5407  * @param	dev	bus device to enumerate
5408  */
5409 void
5410 bus_enumerate_hinted_children(device_t bus)
5411 {
5412 	int i;
5413 	const char *dname, *busname;
5414 	int dunit;
5415 
5416 	/*
5417 	 * enumerate all devices on the specific bus
5418 	 */
5419 	busname = device_get_nameunit(bus);
5420 	i = 0;
5421 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5422 		BUS_HINTED_CHILD(bus, dname, dunit);
5423 
5424 	/*
5425 	 * and all the generic ones.
5426 	 */
5427 	busname = device_get_name(bus);
5428 	i = 0;
5429 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5430 		BUS_HINTED_CHILD(bus, dname, dunit);
5431 }
5432 
5433 #ifdef BUS_DEBUG
5434 
5435 /* the _short versions avoid iteration by not calling anything that prints
5436  * more than oneliners. I love oneliners.
5437  */
5438 
5439 static void
5440 print_device_short(device_t dev, int indent)
5441 {
5442 	if (!dev)
5443 		return;
5444 
5445 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5446 	    dev->unit, dev->desc,
5447 	    (dev->parent? "":"no "),
5448 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5449 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5450 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5451 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5452 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5453 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5454 	    (dev->ivars? "":"no "),
5455 	    (dev->softc? "":"no "),
5456 	    dev->busy));
5457 }
5458 
5459 static void
5460 print_device(device_t dev, int indent)
5461 {
5462 	if (!dev)
5463 		return;
5464 
5465 	print_device_short(dev, indent);
5466 
5467 	indentprintf(("Parent:\n"));
5468 	print_device_short(dev->parent, indent+1);
5469 	indentprintf(("Driver:\n"));
5470 	print_driver_short(dev->driver, indent+1);
5471 	indentprintf(("Devclass:\n"));
5472 	print_devclass_short(dev->devclass, indent+1);
5473 }
5474 
5475 void
5476 print_device_tree_short(device_t dev, int indent)
5477 /* print the device and all its children (indented) */
5478 {
5479 	device_t child;
5480 
5481 	if (!dev)
5482 		return;
5483 
5484 	print_device_short(dev, indent);
5485 
5486 	TAILQ_FOREACH(child, &dev->children, link) {
5487 		print_device_tree_short(child, indent+1);
5488 	}
5489 }
5490 
5491 void
5492 print_device_tree(device_t dev, int indent)
5493 /* print the device and all its children (indented) */
5494 {
5495 	device_t child;
5496 
5497 	if (!dev)
5498 		return;
5499 
5500 	print_device(dev, indent);
5501 
5502 	TAILQ_FOREACH(child, &dev->children, link) {
5503 		print_device_tree(child, indent+1);
5504 	}
5505 }
5506 
5507 static void
5508 print_driver_short(driver_t *driver, int indent)
5509 {
5510 	if (!driver)
5511 		return;
5512 
5513 	indentprintf(("driver %s: softc size = %zd\n",
5514 	    driver->name, driver->size));
5515 }
5516 
5517 static void
5518 print_driver(driver_t *driver, int indent)
5519 {
5520 	if (!driver)
5521 		return;
5522 
5523 	print_driver_short(driver, indent);
5524 }
5525 
5526 static void
5527 print_driver_list(driver_list_t drivers, int indent)
5528 {
5529 	driverlink_t driver;
5530 
5531 	TAILQ_FOREACH(driver, &drivers, link) {
5532 		print_driver(driver->driver, indent);
5533 	}
5534 }
5535 
5536 static void
5537 print_devclass_short(devclass_t dc, int indent)
5538 {
5539 	if ( !dc )
5540 		return;
5541 
5542 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5543 }
5544 
5545 static void
5546 print_devclass(devclass_t dc, int indent)
5547 {
5548 	int i;
5549 
5550 	if ( !dc )
5551 		return;
5552 
5553 	print_devclass_short(dc, indent);
5554 	indentprintf(("Drivers:\n"));
5555 	print_driver_list(dc->drivers, indent+1);
5556 
5557 	indentprintf(("Devices:\n"));
5558 	for (i = 0; i < dc->maxunit; i++)
5559 		if (dc->devices[i])
5560 			print_device(dc->devices[i], indent+1);
5561 }
5562 
5563 void
5564 print_devclass_list_short(void)
5565 {
5566 	devclass_t dc;
5567 
5568 	printf("Short listing of devclasses, drivers & devices:\n");
5569 	TAILQ_FOREACH(dc, &devclasses, link) {
5570 		print_devclass_short(dc, 0);
5571 	}
5572 }
5573 
5574 void
5575 print_devclass_list(void)
5576 {
5577 	devclass_t dc;
5578 
5579 	printf("Full listing of devclasses, drivers & devices:\n");
5580 	TAILQ_FOREACH(dc, &devclasses, link) {
5581 		print_devclass(dc, 0);
5582 	}
5583 }
5584 
5585 #endif
5586 
5587 /*
5588  * User-space access to the device tree.
5589  *
5590  * We implement a small set of nodes:
5591  *
5592  * hw.bus			Single integer read method to obtain the
5593  *				current generation count.
5594  * hw.bus.devices		Reads the entire device tree in flat space.
5595  * hw.bus.rman			Resource manager interface
5596  *
5597  * We might like to add the ability to scan devclasses and/or drivers to
5598  * determine what else is currently loaded/available.
5599  */
5600 
5601 static int
5602 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5603 {
5604 	struct u_businfo	ubus;
5605 
5606 	ubus.ub_version = BUS_USER_VERSION;
5607 	ubus.ub_generation = bus_data_generation;
5608 
5609 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5610 }
5611 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5612     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5613     "bus-related data");
5614 
5615 static int
5616 sysctl_devices(SYSCTL_HANDLER_ARGS)
5617 {
5618 	struct sbuf		sb;
5619 	int			*name = (int *)arg1;
5620 	u_int			namelen = arg2;
5621 	int			index;
5622 	device_t		dev;
5623 	struct u_device		*udev;
5624 	int			error;
5625 
5626 	if (namelen != 2)
5627 		return (EINVAL);
5628 
5629 	if (bus_data_generation_check(name[0]))
5630 		return (EINVAL);
5631 
5632 	index = name[1];
5633 
5634 	/*
5635 	 * Scan the list of devices, looking for the requested index.
5636 	 */
5637 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5638 		if (index-- == 0)
5639 			break;
5640 	}
5641 	if (dev == NULL)
5642 		return (ENOENT);
5643 
5644 	/*
5645 	 * Populate the return item, careful not to overflow the buffer.
5646 	 */
5647 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5648 	if (udev == NULL)
5649 		return (ENOMEM);
5650 	udev->dv_handle = (uintptr_t)dev;
5651 	udev->dv_parent = (uintptr_t)dev->parent;
5652 	udev->dv_devflags = dev->devflags;
5653 	udev->dv_flags = dev->flags;
5654 	udev->dv_state = dev->state;
5655 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5656 	if (dev->nameunit != NULL)
5657 		sbuf_cat(&sb, dev->nameunit);
5658 	sbuf_putc(&sb, '\0');
5659 	if (dev->desc != NULL)
5660 		sbuf_cat(&sb, dev->desc);
5661 	sbuf_putc(&sb, '\0');
5662 	if (dev->driver != NULL)
5663 		sbuf_cat(&sb, dev->driver->name);
5664 	sbuf_putc(&sb, '\0');
5665 	bus_child_pnpinfo(dev, &sb);
5666 	sbuf_putc(&sb, '\0');
5667 	bus_child_location(dev, &sb);
5668 	sbuf_putc(&sb, '\0');
5669 	error = sbuf_finish(&sb);
5670 	if (error == 0)
5671 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5672 	sbuf_delete(&sb);
5673 	free(udev, M_BUS);
5674 	return (error);
5675 }
5676 
5677 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5678     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5679     "system device tree");
5680 
5681 int
5682 bus_data_generation_check(int generation)
5683 {
5684 	if (generation != bus_data_generation)
5685 		return (1);
5686 
5687 	/* XXX generate optimised lists here? */
5688 	return (0);
5689 }
5690 
5691 void
5692 bus_data_generation_update(void)
5693 {
5694 	atomic_add_int(&bus_data_generation, 1);
5695 }
5696 
5697 int
5698 bus_free_resource(device_t dev, int type, struct resource *r)
5699 {
5700 	if (r == NULL)
5701 		return (0);
5702 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5703 }
5704 
5705 device_t
5706 device_lookup_by_name(const char *name)
5707 {
5708 	device_t dev;
5709 
5710 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5711 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5712 			return (dev);
5713 	}
5714 	return (NULL);
5715 }
5716 
5717 /*
5718  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5719  * implicit semantics on open, so it could not be reused for this.
5720  * Another option would be to call this /dev/bus?
5721  */
5722 static int
5723 find_device(struct devreq *req, device_t *devp)
5724 {
5725 	device_t dev;
5726 
5727 	/*
5728 	 * First, ensure that the name is nul terminated.
5729 	 */
5730 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5731 		return (EINVAL);
5732 
5733 	/*
5734 	 * Second, try to find an attached device whose name matches
5735 	 * 'name'.
5736 	 */
5737 	dev = device_lookup_by_name(req->dr_name);
5738 	if (dev != NULL) {
5739 		*devp = dev;
5740 		return (0);
5741 	}
5742 
5743 	/* Finally, give device enumerators a chance. */
5744 	dev = NULL;
5745 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5746 	if (dev == NULL)
5747 		return (ENOENT);
5748 	*devp = dev;
5749 	return (0);
5750 }
5751 
5752 static bool
5753 driver_exists(device_t bus, const char *driver)
5754 {
5755 	devclass_t dc;
5756 
5757 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5758 		if (devclass_find_driver_internal(dc, driver) != NULL)
5759 			return (true);
5760 	}
5761 	return (false);
5762 }
5763 
5764 static void
5765 device_gen_nomatch(device_t dev)
5766 {
5767 	device_t child;
5768 
5769 	if (dev->flags & DF_NEEDNOMATCH &&
5770 	    dev->state == DS_NOTPRESENT) {
5771 		BUS_PROBE_NOMATCH(dev->parent, dev);
5772 		devnomatch(dev);
5773 		dev->flags |= DF_DONENOMATCH;
5774 	}
5775 	dev->flags &= ~DF_NEEDNOMATCH;
5776 	TAILQ_FOREACH(child, &dev->children, link) {
5777 		device_gen_nomatch(child);
5778 	}
5779 }
5780 
5781 static void
5782 device_do_deferred_actions(void)
5783 {
5784 	devclass_t dc;
5785 	driverlink_t dl;
5786 
5787 	/*
5788 	 * Walk through the devclasses to find all the drivers we've tagged as
5789 	 * deferred during the freeze and call the driver added routines. They
5790 	 * have already been added to the lists in the background, so the driver
5791 	 * added routines that trigger a probe will have all the right bidders
5792 	 * for the probe auction.
5793 	 */
5794 	TAILQ_FOREACH(dc, &devclasses, link) {
5795 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5796 			if (dl->flags & DL_DEFERRED_PROBE) {
5797 				devclass_driver_added(dc, dl->driver);
5798 				dl->flags &= ~DL_DEFERRED_PROBE;
5799 			}
5800 		}
5801 	}
5802 
5803 	/*
5804 	 * We also defer no-match events during a freeze. Walk the tree and
5805 	 * generate all the pent-up events that are still relevant.
5806 	 */
5807 	device_gen_nomatch(root_bus);
5808 	bus_data_generation_update();
5809 }
5810 
5811 static char *
5812 device_get_path(device_t dev, const char *locator)
5813 {
5814 	struct sbuf *sb;
5815 	ssize_t len;
5816 	char *rv = NULL;
5817 	int error;
5818 
5819 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND | SBUF_INCLUDENUL);
5820 	error = BUS_GET_DEVICE_PATH(device_get_parent(dev), dev, locator, sb);
5821 	sbuf_finish(sb);	/* Note: errors checked with sbuf_len() below */
5822 	if (error != 0)
5823 		goto out;
5824 	len = sbuf_len(sb);
5825 	if (len <= 1)
5826 		goto out;
5827 	rv = malloc(len, M_BUS, M_NOWAIT);
5828 	memcpy(rv, sbuf_data(sb), len);
5829 out:
5830 	sbuf_delete(sb);
5831 	return (rv);
5832 }
5833 
5834 static int
5835 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5836     struct thread *td)
5837 {
5838 	struct devreq *req;
5839 	device_t dev;
5840 	int error, old;
5841 
5842 	/* Locate the device to control. */
5843 	bus_topo_lock();
5844 	req = (struct devreq *)data;
5845 	switch (cmd) {
5846 	case DEV_ATTACH:
5847 	case DEV_DETACH:
5848 	case DEV_ENABLE:
5849 	case DEV_DISABLE:
5850 	case DEV_SUSPEND:
5851 	case DEV_RESUME:
5852 	case DEV_SET_DRIVER:
5853 	case DEV_CLEAR_DRIVER:
5854 	case DEV_RESCAN:
5855 	case DEV_DELETE:
5856 	case DEV_RESET:
5857 		error = priv_check(td, PRIV_DRIVER);
5858 		if (error == 0)
5859 			error = find_device(req, &dev);
5860 		break;
5861 	case DEV_FREEZE:
5862 	case DEV_THAW:
5863 		error = priv_check(td, PRIV_DRIVER);
5864 		break;
5865 	case DEV_GET_PATH:
5866 		error = find_device(req, &dev);
5867 		break;
5868 	default:
5869 		error = ENOTTY;
5870 		break;
5871 	}
5872 	if (error) {
5873 		bus_topo_unlock();
5874 		return (error);
5875 	}
5876 
5877 	/* Perform the requested operation. */
5878 	switch (cmd) {
5879 	case DEV_ATTACH:
5880 		if (device_is_attached(dev))
5881 			error = EBUSY;
5882 		else if (!device_is_enabled(dev))
5883 			error = ENXIO;
5884 		else
5885 			error = device_probe_and_attach(dev);
5886 		break;
5887 	case DEV_DETACH:
5888 		if (!device_is_attached(dev)) {
5889 			error = ENXIO;
5890 			break;
5891 		}
5892 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5893 			error = device_quiesce(dev);
5894 			if (error)
5895 				break;
5896 		}
5897 		error = device_detach(dev);
5898 		break;
5899 	case DEV_ENABLE:
5900 		if (device_is_enabled(dev)) {
5901 			error = EBUSY;
5902 			break;
5903 		}
5904 
5905 		/*
5906 		 * If the device has been probed but not attached (e.g.
5907 		 * when it has been disabled by a loader hint), just
5908 		 * attach the device rather than doing a full probe.
5909 		 */
5910 		device_enable(dev);
5911 		if (device_is_alive(dev)) {
5912 			/*
5913 			 * If the device was disabled via a hint, clear
5914 			 * the hint.
5915 			 */
5916 			if (resource_disabled(dev->driver->name, dev->unit))
5917 				resource_unset_value(dev->driver->name,
5918 				    dev->unit, "disabled");
5919 			error = device_attach(dev);
5920 		} else
5921 			error = device_probe_and_attach(dev);
5922 		break;
5923 	case DEV_DISABLE:
5924 		if (!device_is_enabled(dev)) {
5925 			error = ENXIO;
5926 			break;
5927 		}
5928 
5929 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5930 			error = device_quiesce(dev);
5931 			if (error)
5932 				break;
5933 		}
5934 
5935 		/*
5936 		 * Force DF_FIXEDCLASS on around detach to preserve
5937 		 * the existing name.
5938 		 */
5939 		old = dev->flags;
5940 		dev->flags |= DF_FIXEDCLASS;
5941 		error = device_detach(dev);
5942 		if (!(old & DF_FIXEDCLASS))
5943 			dev->flags &= ~DF_FIXEDCLASS;
5944 		if (error == 0)
5945 			device_disable(dev);
5946 		break;
5947 	case DEV_SUSPEND:
5948 		if (device_is_suspended(dev)) {
5949 			error = EBUSY;
5950 			break;
5951 		}
5952 		if (device_get_parent(dev) == NULL) {
5953 			error = EINVAL;
5954 			break;
5955 		}
5956 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5957 		break;
5958 	case DEV_RESUME:
5959 		if (!device_is_suspended(dev)) {
5960 			error = EINVAL;
5961 			break;
5962 		}
5963 		if (device_get_parent(dev) == NULL) {
5964 			error = EINVAL;
5965 			break;
5966 		}
5967 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5968 		break;
5969 	case DEV_SET_DRIVER: {
5970 		devclass_t dc;
5971 		char driver[128];
5972 
5973 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5974 		if (error)
5975 			break;
5976 		if (driver[0] == '\0') {
5977 			error = EINVAL;
5978 			break;
5979 		}
5980 		if (dev->devclass != NULL &&
5981 		    strcmp(driver, dev->devclass->name) == 0)
5982 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5983 			break;
5984 
5985 		/*
5986 		 * Scan drivers for this device's bus looking for at
5987 		 * least one matching driver.
5988 		 */
5989 		if (dev->parent == NULL) {
5990 			error = EINVAL;
5991 			break;
5992 		}
5993 		if (!driver_exists(dev->parent, driver)) {
5994 			error = ENOENT;
5995 			break;
5996 		}
5997 		dc = devclass_create(driver);
5998 		if (dc == NULL) {
5999 			error = ENOMEM;
6000 			break;
6001 		}
6002 
6003 		/* Detach device if necessary. */
6004 		if (device_is_attached(dev)) {
6005 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
6006 				error = device_detach(dev);
6007 			else
6008 				error = EBUSY;
6009 			if (error)
6010 				break;
6011 		}
6012 
6013 		/* Clear any previously-fixed device class and unit. */
6014 		if (dev->flags & DF_FIXEDCLASS)
6015 			devclass_delete_device(dev->devclass, dev);
6016 		dev->flags |= DF_WILDCARD;
6017 		dev->unit = -1;
6018 
6019 		/* Force the new device class. */
6020 		error = devclass_add_device(dc, dev);
6021 		if (error)
6022 			break;
6023 		dev->flags |= DF_FIXEDCLASS;
6024 		error = device_probe_and_attach(dev);
6025 		break;
6026 	}
6027 	case DEV_CLEAR_DRIVER:
6028 		if (!(dev->flags & DF_FIXEDCLASS)) {
6029 			error = 0;
6030 			break;
6031 		}
6032 		if (device_is_attached(dev)) {
6033 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
6034 				error = device_detach(dev);
6035 			else
6036 				error = EBUSY;
6037 			if (error)
6038 				break;
6039 		}
6040 
6041 		dev->flags &= ~DF_FIXEDCLASS;
6042 		dev->flags |= DF_WILDCARD;
6043 		devclass_delete_device(dev->devclass, dev);
6044 		error = device_probe_and_attach(dev);
6045 		break;
6046 	case DEV_RESCAN:
6047 		if (!device_is_attached(dev)) {
6048 			error = ENXIO;
6049 			break;
6050 		}
6051 		error = BUS_RESCAN(dev);
6052 		break;
6053 	case DEV_DELETE: {
6054 		device_t parent;
6055 
6056 		parent = device_get_parent(dev);
6057 		if (parent == NULL) {
6058 			error = EINVAL;
6059 			break;
6060 		}
6061 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
6062 			if (bus_child_present(dev) != 0) {
6063 				error = EBUSY;
6064 				break;
6065 			}
6066 		}
6067 
6068 		error = device_delete_child(parent, dev);
6069 		break;
6070 	}
6071 	case DEV_FREEZE:
6072 		if (device_frozen)
6073 			error = EBUSY;
6074 		else
6075 			device_frozen = true;
6076 		break;
6077 	case DEV_THAW:
6078 		if (!device_frozen)
6079 			error = EBUSY;
6080 		else {
6081 			device_do_deferred_actions();
6082 			device_frozen = false;
6083 		}
6084 		break;
6085 	case DEV_RESET:
6086 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
6087 			error = EINVAL;
6088 			break;
6089 		}
6090 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
6091 		    req->dr_flags);
6092 		break;
6093 	case DEV_GET_PATH: {
6094 		char locator[64];
6095 		char *path;
6096 		ssize_t len;
6097 
6098 		error = copyinstr(req->dr_buffer.buffer, locator, sizeof(locator), NULL);
6099 		if (error)
6100 			break;
6101 		path = device_get_path(dev, locator);
6102 		if (path == NULL) {
6103 			error = ENOMEM;
6104 			break;
6105 		}
6106 		len = strlen(path) + 1;
6107 		if (req->dr_buffer.length < len) {
6108 			error = ENAMETOOLONG;
6109 		} else {
6110 			error = copyout(path, req->dr_buffer.buffer, len);
6111 		}
6112 		req->dr_buffer.length = len;
6113 		free(path, M_BUS);
6114 		break;
6115 	}
6116 	}
6117 	bus_topo_unlock();
6118 	return (error);
6119 }
6120 
6121 static struct cdevsw devctl2_cdevsw = {
6122 	.d_version =	D_VERSION,
6123 	.d_ioctl =	devctl2_ioctl,
6124 	.d_name =	"devctl2",
6125 };
6126 
6127 static void
6128 devctl2_init(void)
6129 {
6130 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
6131 	    UID_ROOT, GID_WHEEL, 0644, "devctl2");
6132 }
6133 
6134 /*
6135  * For maintaining device 'at' location info to avoid recomputing it
6136  */
6137 struct device_location_node {
6138 	const char *dln_locator;
6139 	const char *dln_path;
6140 	TAILQ_ENTRY(device_location_node) dln_link;
6141 };
6142 typedef TAILQ_HEAD(device_location_list, device_location_node) device_location_list_t;
6143 
6144 struct device_location_cache {
6145 	device_location_list_t dlc_list;
6146 };
6147 
6148 
6149 /*
6150  * Location cache for wired devices.
6151  */
6152 device_location_cache_t *
6153 dev_wired_cache_init(void)
6154 {
6155 	device_location_cache_t *dcp;
6156 
6157 	dcp = malloc(sizeof(*dcp), M_BUS, M_WAITOK | M_ZERO);
6158 	TAILQ_INIT(&dcp->dlc_list);
6159 
6160 	return (dcp);
6161 }
6162 
6163 void
6164 dev_wired_cache_fini(device_location_cache_t *dcp)
6165 {
6166 	struct device_location_node *dln, *tdln;
6167 
6168 	TAILQ_FOREACH_SAFE(dln, &dcp->dlc_list, dln_link, tdln) {
6169 		/* Note: one allocation for both node and locator, but not path */
6170 		free(__DECONST(void *, dln->dln_path), M_BUS);
6171 		free(dln, M_BUS);
6172 	}
6173 	free(dcp, M_BUS);
6174 }
6175 
6176 static struct device_location_node *
6177 dev_wired_cache_lookup(device_location_cache_t *dcp, const char *locator)
6178 {
6179 	struct device_location_node *dln;
6180 
6181 	TAILQ_FOREACH(dln, &dcp->dlc_list, dln_link) {
6182 		if (strcmp(locator, dln->dln_locator) == 0)
6183 			return (dln);
6184 	}
6185 
6186 	return (NULL);
6187 }
6188 
6189 static struct device_location_node *
6190 dev_wired_cache_add(device_location_cache_t *dcp, const char *locator, const char *path)
6191 {
6192 	struct device_location_node *dln;
6193 	char *l;
6194 
6195 	dln = malloc(sizeof(*dln) + strlen(locator) + 1, M_BUS, M_WAITOK | M_ZERO);
6196 	dln->dln_locator = l = (char *)(dln + 1);
6197 	memcpy(l, locator, strlen(locator) + 1);
6198 	dln->dln_path = path;
6199 	TAILQ_INSERT_HEAD(&dcp->dlc_list, dln, dln_link);
6200 
6201 	return (dln);
6202 }
6203 
6204 bool
6205 dev_wired_cache_match(device_location_cache_t *dcp, device_t dev, const char *at)
6206 {
6207 	const char *cp, *path;
6208 	char locator[32];
6209 	int len;
6210 	struct device_location_node *res;
6211 
6212 	cp = strchr(at, ':');
6213 	if (cp == NULL)
6214 		return (false);
6215 	len = cp - at;
6216 	if (len > sizeof(locator) - 1)	/* Skip too long locator */
6217 		return (false);
6218 	memcpy(locator, at, len);
6219 	locator[len] = '\0';
6220 	cp++;
6221 
6222 	/* maybe cache this inside device_t and look that up, but not yet */
6223 	res = dev_wired_cache_lookup(dcp, locator);
6224 	if (res == NULL) {
6225 		path = device_get_path(dev, locator);
6226 		res = dev_wired_cache_add(dcp, locator, path);
6227 	}
6228 	if (res == NULL || res->dln_path == NULL)
6229 		return (false);
6230 
6231 	return (strcmp(res->dln_path, cp) == 0);
6232 }
6233 
6234 /*
6235  * APIs to manage deprecation and obsolescence.
6236  */
6237 static int obsolete_panic = 0;
6238 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
6239     "Panic when obsolete features are used (0 = never, 1 = if obsolete, "
6240     "2 = if deprecated)");
6241 
6242 static void
6243 gone_panic(int major, int running, const char *msg)
6244 {
6245 	switch (obsolete_panic)
6246 	{
6247 	case 0:
6248 		return;
6249 	case 1:
6250 		if (running < major)
6251 			return;
6252 		/* FALLTHROUGH */
6253 	default:
6254 		panic("%s", msg);
6255 	}
6256 }
6257 
6258 void
6259 _gone_in(int major, const char *msg)
6260 {
6261 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6262 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6263 		printf("Obsolete code will be removed soon: %s\n", msg);
6264 	else
6265 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6266 		    major, msg);
6267 }
6268 
6269 void
6270 _gone_in_dev(device_t dev, int major, const char *msg)
6271 {
6272 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6273 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6274 		device_printf(dev,
6275 		    "Obsolete code will be removed soon: %s\n", msg);
6276 	else
6277 		device_printf(dev,
6278 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6279 		    major, msg);
6280 }
6281 
6282 #ifdef DDB
6283 DB_SHOW_COMMAND(device, db_show_device)
6284 {
6285 	device_t dev;
6286 
6287 	if (!have_addr)
6288 		return;
6289 
6290 	dev = (device_t)addr;
6291 
6292 	db_printf("name:    %s\n", device_get_nameunit(dev));
6293 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6294 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6295 	db_printf("  addr:    %p\n", dev);
6296 	db_printf("  parent:  %p\n", dev->parent);
6297 	db_printf("  softc:   %p\n", dev->softc);
6298 	db_printf("  ivars:   %p\n", dev->ivars);
6299 }
6300 
6301 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6302 {
6303 	device_t dev;
6304 
6305 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6306 		db_show_device((db_expr_t)dev, true, count, modif);
6307 	}
6308 }
6309 #endif
6310