xref: /freebsd/sys/kern/subr_bus.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997,1998,2003 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_bus.h"
33 #include "opt_ddb.h"
34 
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/domainset.h>
38 #include <sys/eventhandler.h>
39 #include <sys/filio.h>
40 #include <sys/lock.h>
41 #include <sys/kernel.h>
42 #include <sys/kobj.h>
43 #include <sys/limits.h>
44 #include <sys/malloc.h>
45 #include <sys/module.h>
46 #include <sys/mutex.h>
47 #include <sys/poll.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/condvar.h>
51 #include <sys/queue.h>
52 #include <machine/bus.h>
53 #include <sys/random.h>
54 #include <sys/rman.h>
55 #include <sys/sbuf.h>
56 #include <sys/selinfo.h>
57 #include <sys/signalvar.h>
58 #include <sys/smp.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61 #include <sys/uio.h>
62 #include <sys/bus.h>
63 #include <sys/cpuset.h>
64 
65 #include <net/vnet.h>
66 
67 #include <machine/cpu.h>
68 #include <machine/stdarg.h>
69 
70 #include <vm/uma.h>
71 #include <vm/vm.h>
72 
73 #include <ddb/ddb.h>
74 
75 SYSCTL_NODE(_hw, OID_AUTO, bus, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
76     NULL);
77 SYSCTL_ROOT_NODE(OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
78     NULL);
79 
80 /*
81  * Used to attach drivers to devclasses.
82  */
83 typedef struct driverlink *driverlink_t;
84 struct driverlink {
85 	kobj_class_t	driver;
86 	TAILQ_ENTRY(driverlink) link;	/* list of drivers in devclass */
87 	int		pass;
88 	int		flags;
89 #define DL_DEFERRED_PROBE	1	/* Probe deferred on this */
90 	TAILQ_ENTRY(driverlink) passlink;
91 };
92 
93 /*
94  * Forward declarations
95  */
96 typedef TAILQ_HEAD(devclass_list, devclass) devclass_list_t;
97 typedef TAILQ_HEAD(driver_list, driverlink) driver_list_t;
98 typedef TAILQ_HEAD(device_list, device) device_list_t;
99 
100 struct devclass {
101 	TAILQ_ENTRY(devclass) link;
102 	devclass_t	parent;		/* parent in devclass hierarchy */
103 	driver_list_t	drivers;     /* bus devclasses store drivers for bus */
104 	char		*name;
105 	device_t	*devices;	/* array of devices indexed by unit */
106 	int		maxunit;	/* size of devices array */
107 	int		flags;
108 #define DC_HAS_CHILDREN		1
109 
110 	struct sysctl_ctx_list sysctl_ctx;
111 	struct sysctl_oid *sysctl_tree;
112 };
113 
114 /**
115  * @brief Implementation of device.
116  */
117 struct device {
118 	/*
119 	 * A device is a kernel object. The first field must be the
120 	 * current ops table for the object.
121 	 */
122 	KOBJ_FIELDS;
123 
124 	/*
125 	 * Device hierarchy.
126 	 */
127 	TAILQ_ENTRY(device)	link;	/**< list of devices in parent */
128 	TAILQ_ENTRY(device)	devlink; /**< global device list membership */
129 	device_t	parent;		/**< parent of this device  */
130 	device_list_t	children;	/**< list of child devices */
131 
132 	/*
133 	 * Details of this device.
134 	 */
135 	driver_t	*driver;	/**< current driver */
136 	devclass_t	devclass;	/**< current device class */
137 	int		unit;		/**< current unit number */
138 	char*		nameunit;	/**< name+unit e.g. foodev0 */
139 	char*		desc;		/**< driver specific description */
140 	int		busy;		/**< count of calls to device_busy() */
141 	device_state_t	state;		/**< current device state  */
142 	uint32_t	devflags;	/**< api level flags for device_get_flags() */
143 	u_int		flags;		/**< internal device flags  */
144 	u_int	order;			/**< order from device_add_child_ordered() */
145 	void	*ivars;			/**< instance variables  */
146 	void	*softc;			/**< current driver's variables  */
147 
148 	struct sysctl_ctx_list sysctl_ctx; /**< state for sysctl variables  */
149 	struct sysctl_oid *sysctl_tree;	/**< state for sysctl variables */
150 };
151 
152 static MALLOC_DEFINE(M_BUS, "bus", "Bus data structures");
153 static MALLOC_DEFINE(M_BUS_SC, "bus-sc", "Bus data structures, softc");
154 
155 EVENTHANDLER_LIST_DEFINE(device_attach);
156 EVENTHANDLER_LIST_DEFINE(device_detach);
157 EVENTHANDLER_LIST_DEFINE(dev_lookup);
158 
159 static int bus_child_location_sb(device_t child, struct sbuf *sb);
160 static int bus_child_pnpinfo_sb(device_t child, struct sbuf *sb);
161 static void devctl2_init(void);
162 static bool device_frozen;
163 
164 #define DRIVERNAME(d)	((d)? d->name : "no driver")
165 #define DEVCLANAME(d)	((d)? d->name : "no devclass")
166 
167 #ifdef BUS_DEBUG
168 
169 static int bus_debug = 1;
170 SYSCTL_INT(_debug, OID_AUTO, bus_debug, CTLFLAG_RWTUN, &bus_debug, 0,
171     "Bus debug level");
172 #define PDEBUG(a)	if (bus_debug) {printf("%s:%d: ", __func__, __LINE__), printf a; printf("\n");}
173 #define DEVICENAME(d)	((d)? device_get_name(d): "no device")
174 
175 /**
176  * Produce the indenting, indent*2 spaces plus a '.' ahead of that to
177  * prevent syslog from deleting initial spaces
178  */
179 #define indentprintf(p)	do { int iJ; printf("."); for (iJ=0; iJ<indent; iJ++) printf("  "); printf p ; } while (0)
180 
181 static void print_device_short(device_t dev, int indent);
182 static void print_device(device_t dev, int indent);
183 void print_device_tree_short(device_t dev, int indent);
184 void print_device_tree(device_t dev, int indent);
185 static void print_driver_short(driver_t *driver, int indent);
186 static void print_driver(driver_t *driver, int indent);
187 static void print_driver_list(driver_list_t drivers, int indent);
188 static void print_devclass_short(devclass_t dc, int indent);
189 static void print_devclass(devclass_t dc, int indent);
190 void print_devclass_list_short(void);
191 void print_devclass_list(void);
192 
193 #else
194 /* Make the compiler ignore the function calls */
195 #define PDEBUG(a)			/* nop */
196 #define DEVICENAME(d)			/* nop */
197 
198 #define print_device_short(d,i)		/* nop */
199 #define print_device(d,i)		/* nop */
200 #define print_device_tree_short(d,i)	/* nop */
201 #define print_device_tree(d,i)		/* nop */
202 #define print_driver_short(d,i)		/* nop */
203 #define print_driver(d,i)		/* nop */
204 #define print_driver_list(d,i)		/* nop */
205 #define print_devclass_short(d,i)	/* nop */
206 #define print_devclass(d,i)		/* nop */
207 #define print_devclass_list_short()	/* nop */
208 #define print_devclass_list()		/* nop */
209 #endif
210 
211 /*
212  * dev sysctl tree
213  */
214 
215 enum {
216 	DEVCLASS_SYSCTL_PARENT,
217 };
218 
219 static int
220 devclass_sysctl_handler(SYSCTL_HANDLER_ARGS)
221 {
222 	devclass_t dc = (devclass_t)arg1;
223 	const char *value;
224 
225 	switch (arg2) {
226 	case DEVCLASS_SYSCTL_PARENT:
227 		value = dc->parent ? dc->parent->name : "";
228 		break;
229 	default:
230 		return (EINVAL);
231 	}
232 	return (SYSCTL_OUT_STR(req, value));
233 }
234 
235 static void
236 devclass_sysctl_init(devclass_t dc)
237 {
238 	if (dc->sysctl_tree != NULL)
239 		return;
240 	sysctl_ctx_init(&dc->sysctl_ctx);
241 	dc->sysctl_tree = SYSCTL_ADD_NODE(&dc->sysctl_ctx,
242 	    SYSCTL_STATIC_CHILDREN(_dev), OID_AUTO, dc->name,
243 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
244 	SYSCTL_ADD_PROC(&dc->sysctl_ctx, SYSCTL_CHILDREN(dc->sysctl_tree),
245 	    OID_AUTO, "%parent",
246 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
247 	    dc, DEVCLASS_SYSCTL_PARENT, devclass_sysctl_handler, "A",
248 	    "parent class");
249 }
250 
251 enum {
252 	DEVICE_SYSCTL_DESC,
253 	DEVICE_SYSCTL_DRIVER,
254 	DEVICE_SYSCTL_LOCATION,
255 	DEVICE_SYSCTL_PNPINFO,
256 	DEVICE_SYSCTL_PARENT,
257 };
258 
259 static int
260 device_sysctl_handler(SYSCTL_HANDLER_ARGS)
261 {
262 	struct sbuf sb;
263 	device_t dev = (device_t)arg1;
264 	int error;
265 
266 	sbuf_new_for_sysctl(&sb, NULL, 1024, req);
267 	sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
268 	switch (arg2) {
269 	case DEVICE_SYSCTL_DESC:
270 		sbuf_cat(&sb, dev->desc ? dev->desc : "");
271 		break;
272 	case DEVICE_SYSCTL_DRIVER:
273 		sbuf_cat(&sb, dev->driver ? dev->driver->name : "");
274 		break;
275 	case DEVICE_SYSCTL_LOCATION:
276 		bus_child_location_sb(dev, &sb);
277 		break;
278 	case DEVICE_SYSCTL_PNPINFO:
279 		bus_child_pnpinfo_sb(dev, &sb);
280 		break;
281 	case DEVICE_SYSCTL_PARENT:
282 		sbuf_cat(&sb, dev->parent ? dev->parent->nameunit : "");
283 		break;
284 	default:
285 		sbuf_delete(&sb);
286 		return (EINVAL);
287 	}
288 	error = sbuf_finish(&sb);
289 	sbuf_delete(&sb);
290 	return (error);
291 }
292 
293 static void
294 device_sysctl_init(device_t dev)
295 {
296 	devclass_t dc = dev->devclass;
297 	int domain;
298 
299 	if (dev->sysctl_tree != NULL)
300 		return;
301 	devclass_sysctl_init(dc);
302 	sysctl_ctx_init(&dev->sysctl_ctx);
303 	dev->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&dev->sysctl_ctx,
304 	    SYSCTL_CHILDREN(dc->sysctl_tree), OID_AUTO,
305 	    dev->nameunit + strlen(dc->name),
306 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "", "device_index");
307 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
308 	    OID_AUTO, "%desc", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
309 	    dev, DEVICE_SYSCTL_DESC, device_sysctl_handler, "A",
310 	    "device description");
311 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
312 	    OID_AUTO, "%driver",
313 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
314 	    dev, DEVICE_SYSCTL_DRIVER, device_sysctl_handler, "A",
315 	    "device driver name");
316 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
317 	    OID_AUTO, "%location",
318 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
319 	    dev, DEVICE_SYSCTL_LOCATION, device_sysctl_handler, "A",
320 	    "device location relative to parent");
321 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
322 	    OID_AUTO, "%pnpinfo",
323 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
324 	    dev, DEVICE_SYSCTL_PNPINFO, device_sysctl_handler, "A",
325 	    "device identification");
326 	SYSCTL_ADD_PROC(&dev->sysctl_ctx, SYSCTL_CHILDREN(dev->sysctl_tree),
327 	    OID_AUTO, "%parent",
328 	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
329 	    dev, DEVICE_SYSCTL_PARENT, device_sysctl_handler, "A",
330 	    "parent device");
331 	if (bus_get_domain(dev, &domain) == 0)
332 		SYSCTL_ADD_INT(&dev->sysctl_ctx,
333 		    SYSCTL_CHILDREN(dev->sysctl_tree), OID_AUTO, "%domain",
334 		    CTLFLAG_RD, NULL, domain, "NUMA domain");
335 }
336 
337 static void
338 device_sysctl_update(device_t dev)
339 {
340 	devclass_t dc = dev->devclass;
341 
342 	if (dev->sysctl_tree == NULL)
343 		return;
344 	sysctl_rename_oid(dev->sysctl_tree, dev->nameunit + strlen(dc->name));
345 }
346 
347 static void
348 device_sysctl_fini(device_t dev)
349 {
350 	if (dev->sysctl_tree == NULL)
351 		return;
352 	sysctl_ctx_free(&dev->sysctl_ctx);
353 	dev->sysctl_tree = NULL;
354 }
355 
356 /*
357  * /dev/devctl implementation
358  */
359 
360 /*
361  * This design allows only one reader for /dev/devctl.  This is not desirable
362  * in the long run, but will get a lot of hair out of this implementation.
363  * Maybe we should make this device a clonable device.
364  *
365  * Also note: we specifically do not attach a device to the device_t tree
366  * to avoid potential chicken and egg problems.  One could argue that all
367  * of this belongs to the root node.
368  */
369 
370 #define DEVCTL_DEFAULT_QUEUE_LEN 1000
371 static int sysctl_devctl_queue(SYSCTL_HANDLER_ARGS);
372 static int devctl_queue_length = DEVCTL_DEFAULT_QUEUE_LEN;
373 SYSCTL_PROC(_hw_bus, OID_AUTO, devctl_queue, CTLTYPE_INT | CTLFLAG_RWTUN |
374     CTLFLAG_MPSAFE, NULL, 0, sysctl_devctl_queue, "I", "devctl queue length");
375 
376 static d_open_t		devopen;
377 static d_close_t	devclose;
378 static d_read_t		devread;
379 static d_ioctl_t	devioctl;
380 static d_poll_t		devpoll;
381 static d_kqfilter_t	devkqfilter;
382 
383 static struct cdevsw dev_cdevsw = {
384 	.d_version =	D_VERSION,
385 	.d_open =	devopen,
386 	.d_close =	devclose,
387 	.d_read =	devread,
388 	.d_ioctl =	devioctl,
389 	.d_poll =	devpoll,
390 	.d_kqfilter =	devkqfilter,
391 	.d_name =	"devctl",
392 };
393 
394 #define DEVCTL_BUFFER (1024 - sizeof(void *))
395 struct dev_event_info {
396 	STAILQ_ENTRY(dev_event_info) dei_link;
397 	char dei_data[DEVCTL_BUFFER];
398 };
399 
400 STAILQ_HEAD(devq, dev_event_info);
401 
402 static struct dev_softc {
403 	int		inuse;
404 	int		nonblock;
405 	int		queued;
406 	int		async;
407 	struct mtx	mtx;
408 	struct cv	cv;
409 	struct selinfo	sel;
410 	struct devq	devq;
411 	struct sigio	*sigio;
412 	uma_zone_t	zone;
413 } devsoftc;
414 
415 static void	filt_devctl_detach(struct knote *kn);
416 static int	filt_devctl_read(struct knote *kn, long hint);
417 
418 struct filterops devctl_rfiltops = {
419 	.f_isfd = 1,
420 	.f_detach = filt_devctl_detach,
421 	.f_event = filt_devctl_read,
422 };
423 
424 static struct cdev *devctl_dev;
425 
426 static void
427 devinit(void)
428 {
429 	int reserve;
430 	uma_zone_t z;
431 
432 	devctl_dev = make_dev_credf(MAKEDEV_ETERNAL, &dev_cdevsw, 0, NULL,
433 	    UID_ROOT, GID_WHEEL, 0600, "devctl");
434 	mtx_init(&devsoftc.mtx, "dev mtx", "devd", MTX_DEF);
435 	cv_init(&devsoftc.cv, "dev cv");
436 	STAILQ_INIT(&devsoftc.devq);
437 	knlist_init_mtx(&devsoftc.sel.si_note, &devsoftc.mtx);
438 	if (devctl_queue_length > 0) {
439 		/*
440 		 * Allocate a zone for the messages. Preallocate 2% of these for
441 		 * a reserve. Allow only devctl_queue_length slabs to cap memory
442 		 * usage.  The reserve usually allows coverage of surges of
443 		 * events during memory shortages. Normally we won't have to
444 		 * re-use events from the queue, but will in extreme shortages.
445 		 */
446 		z = devsoftc.zone = uma_zcreate("DEVCTL",
447 		    sizeof(struct dev_event_info), NULL, NULL, NULL, NULL,
448 		    UMA_ALIGN_PTR, 0);
449 		reserve = max(devctl_queue_length / 50, 100);	/* 2% reserve */
450 		uma_zone_set_max(z, devctl_queue_length);
451 		uma_zone_set_maxcache(z, 0);
452 		uma_zone_reserve(z, reserve);
453 		uma_prealloc(z, reserve);
454 	}
455 	devctl2_init();
456 }
457 
458 static int
459 devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
460 {
461 	mtx_lock(&devsoftc.mtx);
462 	if (devsoftc.inuse) {
463 		mtx_unlock(&devsoftc.mtx);
464 		return (EBUSY);
465 	}
466 	/* move to init */
467 	devsoftc.inuse = 1;
468 	mtx_unlock(&devsoftc.mtx);
469 	return (0);
470 }
471 
472 static int
473 devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
474 {
475 	mtx_lock(&devsoftc.mtx);
476 	devsoftc.inuse = 0;
477 	devsoftc.nonblock = 0;
478 	devsoftc.async = 0;
479 	cv_broadcast(&devsoftc.cv);
480 	funsetown(&devsoftc.sigio);
481 	mtx_unlock(&devsoftc.mtx);
482 	return (0);
483 }
484 
485 /*
486  * The read channel for this device is used to report changes to
487  * userland in realtime.  We are required to free the data as well as
488  * the n1 object because we allocate them separately.  Also note that
489  * we return one record at a time.  If you try to read this device a
490  * character at a time, you will lose the rest of the data.  Listening
491  * programs are expected to cope.
492  */
493 static int
494 devread(struct cdev *dev, struct uio *uio, int ioflag)
495 {
496 	struct dev_event_info *n1;
497 	int rv;
498 
499 	mtx_lock(&devsoftc.mtx);
500 	while (STAILQ_EMPTY(&devsoftc.devq)) {
501 		if (devsoftc.nonblock) {
502 			mtx_unlock(&devsoftc.mtx);
503 			return (EAGAIN);
504 		}
505 		rv = cv_wait_sig(&devsoftc.cv, &devsoftc.mtx);
506 		if (rv) {
507 			/*
508 			 * Need to translate ERESTART to EINTR here? -- jake
509 			 */
510 			mtx_unlock(&devsoftc.mtx);
511 			return (rv);
512 		}
513 	}
514 	n1 = STAILQ_FIRST(&devsoftc.devq);
515 	STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
516 	devsoftc.queued--;
517 	mtx_unlock(&devsoftc.mtx);
518 	rv = uiomove(n1->dei_data, strlen(n1->dei_data), uio);
519 	uma_zfree(devsoftc.zone, n1);
520 	return (rv);
521 }
522 
523 static	int
524 devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
525 {
526 	switch (cmd) {
527 	case FIONBIO:
528 		if (*(int*)data)
529 			devsoftc.nonblock = 1;
530 		else
531 			devsoftc.nonblock = 0;
532 		return (0);
533 	case FIOASYNC:
534 		if (*(int*)data)
535 			devsoftc.async = 1;
536 		else
537 			devsoftc.async = 0;
538 		return (0);
539 	case FIOSETOWN:
540 		return fsetown(*(int *)data, &devsoftc.sigio);
541 	case FIOGETOWN:
542 		*(int *)data = fgetown(&devsoftc.sigio);
543 		return (0);
544 
545 		/* (un)Support for other fcntl() calls. */
546 	case FIOCLEX:
547 	case FIONCLEX:
548 	case FIONREAD:
549 	default:
550 		break;
551 	}
552 	return (ENOTTY);
553 }
554 
555 static	int
556 devpoll(struct cdev *dev, int events, struct thread *td)
557 {
558 	int	revents = 0;
559 
560 	mtx_lock(&devsoftc.mtx);
561 	if (events & (POLLIN | POLLRDNORM)) {
562 		if (!STAILQ_EMPTY(&devsoftc.devq))
563 			revents = events & (POLLIN | POLLRDNORM);
564 		else
565 			selrecord(td, &devsoftc.sel);
566 	}
567 	mtx_unlock(&devsoftc.mtx);
568 
569 	return (revents);
570 }
571 
572 static int
573 devkqfilter(struct cdev *dev, struct knote *kn)
574 {
575 	int error;
576 
577 	if (kn->kn_filter == EVFILT_READ) {
578 		kn->kn_fop = &devctl_rfiltops;
579 		knlist_add(&devsoftc.sel.si_note, kn, 0);
580 		error = 0;
581 	} else
582 		error = EINVAL;
583 	return (error);
584 }
585 
586 static void
587 filt_devctl_detach(struct knote *kn)
588 {
589 	knlist_remove(&devsoftc.sel.si_note, kn, 0);
590 }
591 
592 static int
593 filt_devctl_read(struct knote *kn, long hint)
594 {
595 	kn->kn_data = devsoftc.queued;
596 	return (kn->kn_data != 0);
597 }
598 
599 /**
600  * @brief Return whether the userland process is running
601  */
602 bool
603 devctl_process_running(void)
604 {
605 	return (devsoftc.inuse == 1);
606 }
607 
608 static struct dev_event_info *
609 devctl_alloc_dei(void)
610 {
611 	struct dev_event_info *dei = NULL;
612 
613 	mtx_lock(&devsoftc.mtx);
614 	if (devctl_queue_length == 0)
615 		goto out;
616 	dei = uma_zalloc(devsoftc.zone, M_NOWAIT);
617 	if (dei == NULL)
618 		dei = uma_zalloc(devsoftc.zone, M_NOWAIT | M_USE_RESERVE);
619 	if (dei == NULL) {
620 		/*
621 		 * Guard against no items in the queue. Normally, this won't
622 		 * happen, but if lots of events happen all at once and there's
623 		 * a chance we're out of allocated space but none have yet been
624 		 * queued when we get here, leaving nothing to steal. This can
625 		 * also happen with error injection. Fail safe by returning
626 		 * NULL in that case..
627 		 */
628 		if (devsoftc.queued == 0)
629 			goto out;
630 		dei = STAILQ_FIRST(&devsoftc.devq);
631 		STAILQ_REMOVE_HEAD(&devsoftc.devq, dei_link);
632 		devsoftc.queued--;
633 	}
634 	MPASS(dei != NULL);
635 	*dei->dei_data = '\0';
636 out:
637 	mtx_unlock(&devsoftc.mtx);
638 	return (dei);
639 }
640 
641 static struct dev_event_info *
642 devctl_alloc_dei_sb(struct sbuf *sb)
643 {
644 	struct dev_event_info *dei;
645 
646 	dei = devctl_alloc_dei();
647 	if (dei != NULL)
648 		sbuf_new(sb, dei->dei_data, sizeof(dei->dei_data), SBUF_FIXEDLEN);
649 	return (dei);
650 }
651 
652 static void
653 devctl_free_dei(struct dev_event_info *dei)
654 {
655 	uma_zfree(devsoftc.zone, dei);
656 }
657 
658 static void
659 devctl_queue(struct dev_event_info *dei)
660 {
661 	mtx_lock(&devsoftc.mtx);
662 	STAILQ_INSERT_TAIL(&devsoftc.devq, dei, dei_link);
663 	devsoftc.queued++;
664 	cv_broadcast(&devsoftc.cv);
665 	KNOTE_LOCKED(&devsoftc.sel.si_note, 0);
666 	mtx_unlock(&devsoftc.mtx);
667 	selwakeup(&devsoftc.sel);
668 	if (devsoftc.async && devsoftc.sigio != NULL)
669 		pgsigio(&devsoftc.sigio, SIGIO, 0);
670 }
671 
672 /**
673  * @brief Send a 'notification' to userland, using standard ways
674  */
675 void
676 devctl_notify(const char *system, const char *subsystem, const char *type,
677     const char *data)
678 {
679 	struct dev_event_info *dei;
680 	struct sbuf sb;
681 
682 	if (system == NULL || subsystem == NULL || type == NULL)
683 		return;
684 	dei = devctl_alloc_dei_sb(&sb);
685 	if (dei == NULL)
686 		return;
687 	sbuf_cpy(&sb, "!system=");
688 	sbuf_cat(&sb, system);
689 	sbuf_cat(&sb, " subsystem=");
690 	sbuf_cat(&sb, subsystem);
691 	sbuf_cat(&sb, " type=");
692 	sbuf_cat(&sb, type);
693 	if (data != NULL) {
694 		sbuf_putc(&sb, ' ');
695 		sbuf_cat(&sb, data);
696 	}
697 	sbuf_putc(&sb, '\n');
698 	if (sbuf_finish(&sb) != 0)
699 		devctl_free_dei(dei);	/* overflow -> drop it */
700 	else
701 		devctl_queue(dei);
702 }
703 
704 /*
705  * Common routine that tries to make sending messages as easy as possible.
706  * We allocate memory for the data, copy strings into that, but do not
707  * free it unless there's an error.  The dequeue part of the driver should
708  * free the data.  We don't send data when the device is disabled.  We do
709  * send data, even when we have no listeners, because we wish to avoid
710  * races relating to startup and restart of listening applications.
711  *
712  * devaddq is designed to string together the type of event, with the
713  * object of that event, plus the plug and play info and location info
714  * for that event.  This is likely most useful for devices, but less
715  * useful for other consumers of this interface.  Those should use
716  * the devctl_notify() interface instead.
717  *
718  * Output:
719  *	${type}${what} at $(location dev) $(pnp-info dev) on $(parent dev)
720  */
721 static void
722 devaddq(const char *type, const char *what, device_t dev)
723 {
724 	struct dev_event_info *dei;
725 	const char *parstr;
726 	struct sbuf sb;
727 
728 	dei = devctl_alloc_dei_sb(&sb);
729 	if (dei == NULL)
730 		return;
731 	sbuf_cpy(&sb, type);
732 	sbuf_cat(&sb, what);
733 	sbuf_cat(&sb, " at ");
734 
735 	/* Add in the location */
736 	bus_child_location_sb(dev, &sb);
737 	sbuf_putc(&sb, ' ');
738 
739 	/* Add in pnpinfo */
740 	bus_child_pnpinfo_sb(dev, &sb);
741 
742 	/* Get the parent of this device, or / if high enough in the tree. */
743 	if (device_get_parent(dev) == NULL)
744 		parstr = ".";	/* Or '/' ? */
745 	else
746 		parstr = device_get_nameunit(device_get_parent(dev));
747 	sbuf_cat(&sb, " on ");
748 	sbuf_cat(&sb, parstr);
749 	sbuf_putc(&sb, '\n');
750 	if (sbuf_finish(&sb) != 0)
751 		goto bad;
752 	devctl_queue(dei);
753 	return;
754 bad:
755 	devctl_free_dei(dei);
756 }
757 
758 /*
759  * A device was added to the tree.  We are called just after it successfully
760  * attaches (that is, probe and attach success for this device).  No call
761  * is made if a device is merely parented into the tree.  See devnomatch
762  * if probe fails.  If attach fails, no notification is sent (but maybe
763  * we should have a different message for this).
764  */
765 static void
766 devadded(device_t dev)
767 {
768 	devaddq("+", device_get_nameunit(dev), dev);
769 }
770 
771 /*
772  * A device was removed from the tree.  We are called just before this
773  * happens.
774  */
775 static void
776 devremoved(device_t dev)
777 {
778 	devaddq("-", device_get_nameunit(dev), dev);
779 }
780 
781 /*
782  * Called when there's no match for this device.  This is only called
783  * the first time that no match happens, so we don't keep getting this
784  * message.  Should that prove to be undesirable, we can change it.
785  * This is called when all drivers that can attach to a given bus
786  * decline to accept this device.  Other errors may not be detected.
787  */
788 static void
789 devnomatch(device_t dev)
790 {
791 	devaddq("?", "", dev);
792 }
793 
794 static int
795 sysctl_devctl_queue(SYSCTL_HANDLER_ARGS)
796 {
797 	int q, error;
798 
799 	q = devctl_queue_length;
800 	error = sysctl_handle_int(oidp, &q, 0, req);
801 	if (error || !req->newptr)
802 		return (error);
803 	if (q < 0)
804 		return (EINVAL);
805 
806 	/*
807 	 * When set as a tunable, we've not yet initialized the mutex.
808 	 * It is safe to just assign to devctl_queue_length and return
809 	 * as we're racing no one. We'll use whatever value set in
810 	 * devinit.
811 	 */
812 	if (!mtx_initialized(&devsoftc.mtx)) {
813 		devctl_queue_length = q;
814 		return (0);
815 	}
816 
817 	/*
818 	 * XXX It's hard to grow or shrink the UMA zone. Only allow
819 	 * disabling the queue size for the moment until underlying
820 	 * UMA issues can be sorted out.
821 	 */
822 	if (q != 0)
823 		return (EINVAL);
824 	if (q == devctl_queue_length)
825 		return (0);
826 	mtx_lock(&devsoftc.mtx);
827 	devctl_queue_length = 0;
828 	uma_zdestroy(devsoftc.zone);
829 	devsoftc.zone = 0;
830 	mtx_unlock(&devsoftc.mtx);
831 	return (0);
832 }
833 
834 /**
835  * @brief safely quotes strings that might have double quotes in them.
836  *
837  * The devctl protocol relies on quoted strings having matching quotes.
838  * This routine quotes any internal quotes so the resulting string
839  * is safe to pass to snprintf to construct, for example pnp info strings.
840  *
841  * @param sb	sbuf to place the characters into
842  * @param src	Original buffer.
843  */
844 void
845 devctl_safe_quote_sb(struct sbuf *sb, const char *src)
846 {
847 	while (*src != '\0') {
848 		if (*src == '"' || *src == '\\')
849 			sbuf_putc(sb, '\\');
850 		sbuf_putc(sb, *src++);
851 	}
852 }
853 
854 /* End of /dev/devctl code */
855 
856 static TAILQ_HEAD(,device)	bus_data_devices;
857 static int bus_data_generation = 1;
858 
859 static kobj_method_t null_methods[] = {
860 	KOBJMETHOD_END
861 };
862 
863 DEFINE_CLASS(null, null_methods, 0);
864 
865 /*
866  * Bus pass implementation
867  */
868 
869 static driver_list_t passes = TAILQ_HEAD_INITIALIZER(passes);
870 int bus_current_pass = BUS_PASS_ROOT;
871 
872 /**
873  * @internal
874  * @brief Register the pass level of a new driver attachment
875  *
876  * Register a new driver attachment's pass level.  If no driver
877  * attachment with the same pass level has been added, then @p new
878  * will be added to the global passes list.
879  *
880  * @param new		the new driver attachment
881  */
882 static void
883 driver_register_pass(struct driverlink *new)
884 {
885 	struct driverlink *dl;
886 
887 	/* We only consider pass numbers during boot. */
888 	if (bus_current_pass == BUS_PASS_DEFAULT)
889 		return;
890 
891 	/*
892 	 * Walk the passes list.  If we already know about this pass
893 	 * then there is nothing to do.  If we don't, then insert this
894 	 * driver link into the list.
895 	 */
896 	TAILQ_FOREACH(dl, &passes, passlink) {
897 		if (dl->pass < new->pass)
898 			continue;
899 		if (dl->pass == new->pass)
900 			return;
901 		TAILQ_INSERT_BEFORE(dl, new, passlink);
902 		return;
903 	}
904 	TAILQ_INSERT_TAIL(&passes, new, passlink);
905 }
906 
907 /**
908  * @brief Raise the current bus pass
909  *
910  * Raise the current bus pass level to @p pass.  Call the BUS_NEW_PASS()
911  * method on the root bus to kick off a new device tree scan for each
912  * new pass level that has at least one driver.
913  */
914 void
915 bus_set_pass(int pass)
916 {
917 	struct driverlink *dl;
918 
919 	if (bus_current_pass > pass)
920 		panic("Attempt to lower bus pass level");
921 
922 	TAILQ_FOREACH(dl, &passes, passlink) {
923 		/* Skip pass values below the current pass level. */
924 		if (dl->pass <= bus_current_pass)
925 			continue;
926 
927 		/*
928 		 * Bail once we hit a driver with a pass level that is
929 		 * too high.
930 		 */
931 		if (dl->pass > pass)
932 			break;
933 
934 		/*
935 		 * Raise the pass level to the next level and rescan
936 		 * the tree.
937 		 */
938 		bus_current_pass = dl->pass;
939 		BUS_NEW_PASS(root_bus);
940 	}
941 
942 	/*
943 	 * If there isn't a driver registered for the requested pass,
944 	 * then bus_current_pass might still be less than 'pass'.  Set
945 	 * it to 'pass' in that case.
946 	 */
947 	if (bus_current_pass < pass)
948 		bus_current_pass = pass;
949 	KASSERT(bus_current_pass == pass, ("Failed to update bus pass level"));
950 }
951 
952 /*
953  * Devclass implementation
954  */
955 
956 static devclass_list_t devclasses = TAILQ_HEAD_INITIALIZER(devclasses);
957 
958 /**
959  * @internal
960  * @brief Find or create a device class
961  *
962  * If a device class with the name @p classname exists, return it,
963  * otherwise if @p create is non-zero create and return a new device
964  * class.
965  *
966  * If @p parentname is non-NULL, the parent of the devclass is set to
967  * the devclass of that name.
968  *
969  * @param classname	the devclass name to find or create
970  * @param parentname	the parent devclass name or @c NULL
971  * @param create	non-zero to create a devclass
972  */
973 static devclass_t
974 devclass_find_internal(const char *classname, const char *parentname,
975 		       int create)
976 {
977 	devclass_t dc;
978 
979 	PDEBUG(("looking for %s", classname));
980 	if (!classname)
981 		return (NULL);
982 
983 	TAILQ_FOREACH(dc, &devclasses, link) {
984 		if (!strcmp(dc->name, classname))
985 			break;
986 	}
987 
988 	if (create && !dc) {
989 		PDEBUG(("creating %s", classname));
990 		dc = malloc(sizeof(struct devclass) + strlen(classname) + 1,
991 		    M_BUS, M_NOWAIT | M_ZERO);
992 		if (!dc)
993 			return (NULL);
994 		dc->parent = NULL;
995 		dc->name = (char*) (dc + 1);
996 		strcpy(dc->name, classname);
997 		TAILQ_INIT(&dc->drivers);
998 		TAILQ_INSERT_TAIL(&devclasses, dc, link);
999 
1000 		bus_data_generation_update();
1001 	}
1002 
1003 	/*
1004 	 * If a parent class is specified, then set that as our parent so
1005 	 * that this devclass will support drivers for the parent class as
1006 	 * well.  If the parent class has the same name don't do this though
1007 	 * as it creates a cycle that can trigger an infinite loop in
1008 	 * device_probe_child() if a device exists for which there is no
1009 	 * suitable driver.
1010 	 */
1011 	if (parentname && dc && !dc->parent &&
1012 	    strcmp(classname, parentname) != 0) {
1013 		dc->parent = devclass_find_internal(parentname, NULL, TRUE);
1014 		dc->parent->flags |= DC_HAS_CHILDREN;
1015 	}
1016 
1017 	return (dc);
1018 }
1019 
1020 /**
1021  * @brief Create a device class
1022  *
1023  * If a device class with the name @p classname exists, return it,
1024  * otherwise create and return a new device class.
1025  *
1026  * @param classname	the devclass name to find or create
1027  */
1028 devclass_t
1029 devclass_create(const char *classname)
1030 {
1031 	return (devclass_find_internal(classname, NULL, TRUE));
1032 }
1033 
1034 /**
1035  * @brief Find a device class
1036  *
1037  * If a device class with the name @p classname exists, return it,
1038  * otherwise return @c NULL.
1039  *
1040  * @param classname	the devclass name to find
1041  */
1042 devclass_t
1043 devclass_find(const char *classname)
1044 {
1045 	return (devclass_find_internal(classname, NULL, FALSE));
1046 }
1047 
1048 /**
1049  * @brief Register that a device driver has been added to a devclass
1050  *
1051  * Register that a device driver has been added to a devclass.  This
1052  * is called by devclass_add_driver to accomplish the recursive
1053  * notification of all the children classes of dc, as well as dc.
1054  * Each layer will have BUS_DRIVER_ADDED() called for all instances of
1055  * the devclass.
1056  *
1057  * We do a full search here of the devclass list at each iteration
1058  * level to save storing children-lists in the devclass structure.  If
1059  * we ever move beyond a few dozen devices doing this, we may need to
1060  * reevaluate...
1061  *
1062  * @param dc		the devclass to edit
1063  * @param driver	the driver that was just added
1064  */
1065 static void
1066 devclass_driver_added(devclass_t dc, driver_t *driver)
1067 {
1068 	devclass_t parent;
1069 	int i;
1070 
1071 	/*
1072 	 * Call BUS_DRIVER_ADDED for any existing buses in this class.
1073 	 */
1074 	for (i = 0; i < dc->maxunit; i++)
1075 		if (dc->devices[i] && device_is_attached(dc->devices[i]))
1076 			BUS_DRIVER_ADDED(dc->devices[i], driver);
1077 
1078 	/*
1079 	 * Walk through the children classes.  Since we only keep a
1080 	 * single parent pointer around, we walk the entire list of
1081 	 * devclasses looking for children.  We set the
1082 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1083 	 * the parent, so we only walk the list for those devclasses
1084 	 * that have children.
1085 	 */
1086 	if (!(dc->flags & DC_HAS_CHILDREN))
1087 		return;
1088 	parent = dc;
1089 	TAILQ_FOREACH(dc, &devclasses, link) {
1090 		if (dc->parent == parent)
1091 			devclass_driver_added(dc, driver);
1092 	}
1093 }
1094 
1095 /**
1096  * @brief Add a device driver to a device class
1097  *
1098  * Add a device driver to a devclass. This is normally called
1099  * automatically by DRIVER_MODULE(). The BUS_DRIVER_ADDED() method of
1100  * all devices in the devclass will be called to allow them to attempt
1101  * to re-probe any unmatched children.
1102  *
1103  * @param dc		the devclass to edit
1104  * @param driver	the driver to register
1105  */
1106 int
1107 devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp)
1108 {
1109 	driverlink_t dl;
1110 	const char *parentname;
1111 
1112 	PDEBUG(("%s", DRIVERNAME(driver)));
1113 
1114 	/* Don't allow invalid pass values. */
1115 	if (pass <= BUS_PASS_ROOT)
1116 		return (EINVAL);
1117 
1118 	dl = malloc(sizeof *dl, M_BUS, M_NOWAIT|M_ZERO);
1119 	if (!dl)
1120 		return (ENOMEM);
1121 
1122 	/*
1123 	 * Compile the driver's methods. Also increase the reference count
1124 	 * so that the class doesn't get freed when the last instance
1125 	 * goes. This means we can safely use static methods and avoids a
1126 	 * double-free in devclass_delete_driver.
1127 	 */
1128 	kobj_class_compile((kobj_class_t) driver);
1129 
1130 	/*
1131 	 * If the driver has any base classes, make the
1132 	 * devclass inherit from the devclass of the driver's
1133 	 * first base class. This will allow the system to
1134 	 * search for drivers in both devclasses for children
1135 	 * of a device using this driver.
1136 	 */
1137 	if (driver->baseclasses)
1138 		parentname = driver->baseclasses[0]->name;
1139 	else
1140 		parentname = NULL;
1141 	*dcp = devclass_find_internal(driver->name, parentname, TRUE);
1142 
1143 	dl->driver = driver;
1144 	TAILQ_INSERT_TAIL(&dc->drivers, dl, link);
1145 	driver->refs++;		/* XXX: kobj_mtx */
1146 	dl->pass = pass;
1147 	driver_register_pass(dl);
1148 
1149 	if (device_frozen) {
1150 		dl->flags |= DL_DEFERRED_PROBE;
1151 	} else {
1152 		devclass_driver_added(dc, driver);
1153 	}
1154 	bus_data_generation_update();
1155 	return (0);
1156 }
1157 
1158 /**
1159  * @brief Register that a device driver has been deleted from a devclass
1160  *
1161  * Register that a device driver has been removed from a devclass.
1162  * This is called by devclass_delete_driver to accomplish the
1163  * recursive notification of all the children classes of busclass, as
1164  * well as busclass.  Each layer will attempt to detach the driver
1165  * from any devices that are children of the bus's devclass.  The function
1166  * will return an error if a device fails to detach.
1167  *
1168  * We do a full search here of the devclass list at each iteration
1169  * level to save storing children-lists in the devclass structure.  If
1170  * we ever move beyond a few dozen devices doing this, we may need to
1171  * reevaluate...
1172  *
1173  * @param busclass	the devclass of the parent bus
1174  * @param dc		the devclass of the driver being deleted
1175  * @param driver	the driver being deleted
1176  */
1177 static int
1178 devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver)
1179 {
1180 	devclass_t parent;
1181 	device_t dev;
1182 	int error, i;
1183 
1184 	/*
1185 	 * Disassociate from any devices.  We iterate through all the
1186 	 * devices in the devclass of the driver and detach any which are
1187 	 * using the driver and which have a parent in the devclass which
1188 	 * we are deleting from.
1189 	 *
1190 	 * Note that since a driver can be in multiple devclasses, we
1191 	 * should not detach devices which are not children of devices in
1192 	 * the affected devclass.
1193 	 *
1194 	 * If we're frozen, we don't generate NOMATCH events. Mark to
1195 	 * generate later.
1196 	 */
1197 	for (i = 0; i < dc->maxunit; i++) {
1198 		if (dc->devices[i]) {
1199 			dev = dc->devices[i];
1200 			if (dev->driver == driver && dev->parent &&
1201 			    dev->parent->devclass == busclass) {
1202 				if ((error = device_detach(dev)) != 0)
1203 					return (error);
1204 				if (device_frozen) {
1205 					dev->flags &= ~DF_DONENOMATCH;
1206 					dev->flags |= DF_NEEDNOMATCH;
1207 				} else {
1208 					BUS_PROBE_NOMATCH(dev->parent, dev);
1209 					devnomatch(dev);
1210 					dev->flags |= DF_DONENOMATCH;
1211 				}
1212 			}
1213 		}
1214 	}
1215 
1216 	/*
1217 	 * Walk through the children classes.  Since we only keep a
1218 	 * single parent pointer around, we walk the entire list of
1219 	 * devclasses looking for children.  We set the
1220 	 * DC_HAS_CHILDREN flag when a child devclass is created on
1221 	 * the parent, so we only walk the list for those devclasses
1222 	 * that have children.
1223 	 */
1224 	if (!(busclass->flags & DC_HAS_CHILDREN))
1225 		return (0);
1226 	parent = busclass;
1227 	TAILQ_FOREACH(busclass, &devclasses, link) {
1228 		if (busclass->parent == parent) {
1229 			error = devclass_driver_deleted(busclass, dc, driver);
1230 			if (error)
1231 				return (error);
1232 		}
1233 	}
1234 	return (0);
1235 }
1236 
1237 /**
1238  * @brief Delete a device driver from a device class
1239  *
1240  * Delete a device driver from a devclass. This is normally called
1241  * automatically by DRIVER_MODULE().
1242  *
1243  * If the driver is currently attached to any devices,
1244  * devclass_delete_driver() will first attempt to detach from each
1245  * device. If one of the detach calls fails, the driver will not be
1246  * deleted.
1247  *
1248  * @param dc		the devclass to edit
1249  * @param driver	the driver to unregister
1250  */
1251 int
1252 devclass_delete_driver(devclass_t busclass, driver_t *driver)
1253 {
1254 	devclass_t dc = devclass_find(driver->name);
1255 	driverlink_t dl;
1256 	int error;
1257 
1258 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1259 
1260 	if (!dc)
1261 		return (0);
1262 
1263 	/*
1264 	 * Find the link structure in the bus' list of drivers.
1265 	 */
1266 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1267 		if (dl->driver == driver)
1268 			break;
1269 	}
1270 
1271 	if (!dl) {
1272 		PDEBUG(("%s not found in %s list", driver->name,
1273 		    busclass->name));
1274 		return (ENOENT);
1275 	}
1276 
1277 	error = devclass_driver_deleted(busclass, dc, driver);
1278 	if (error != 0)
1279 		return (error);
1280 
1281 	TAILQ_REMOVE(&busclass->drivers, dl, link);
1282 	free(dl, M_BUS);
1283 
1284 	/* XXX: kobj_mtx */
1285 	driver->refs--;
1286 	if (driver->refs == 0)
1287 		kobj_class_free((kobj_class_t) driver);
1288 
1289 	bus_data_generation_update();
1290 	return (0);
1291 }
1292 
1293 /**
1294  * @brief Quiesces a set of device drivers from a device class
1295  *
1296  * Quiesce a device driver from a devclass. This is normally called
1297  * automatically by DRIVER_MODULE().
1298  *
1299  * If the driver is currently attached to any devices,
1300  * devclass_quiesece_driver() will first attempt to quiesce each
1301  * device.
1302  *
1303  * @param dc		the devclass to edit
1304  * @param driver	the driver to unregister
1305  */
1306 static int
1307 devclass_quiesce_driver(devclass_t busclass, driver_t *driver)
1308 {
1309 	devclass_t dc = devclass_find(driver->name);
1310 	driverlink_t dl;
1311 	device_t dev;
1312 	int i;
1313 	int error;
1314 
1315 	PDEBUG(("%s from devclass %s", driver->name, DEVCLANAME(busclass)));
1316 
1317 	if (!dc)
1318 		return (0);
1319 
1320 	/*
1321 	 * Find the link structure in the bus' list of drivers.
1322 	 */
1323 	TAILQ_FOREACH(dl, &busclass->drivers, link) {
1324 		if (dl->driver == driver)
1325 			break;
1326 	}
1327 
1328 	if (!dl) {
1329 		PDEBUG(("%s not found in %s list", driver->name,
1330 		    busclass->name));
1331 		return (ENOENT);
1332 	}
1333 
1334 	/*
1335 	 * Quiesce all devices.  We iterate through all the devices in
1336 	 * the devclass of the driver and quiesce any which are using
1337 	 * the driver and which have a parent in the devclass which we
1338 	 * are quiescing.
1339 	 *
1340 	 * Note that since a driver can be in multiple devclasses, we
1341 	 * should not quiesce devices which are not children of
1342 	 * devices in the affected devclass.
1343 	 */
1344 	for (i = 0; i < dc->maxunit; i++) {
1345 		if (dc->devices[i]) {
1346 			dev = dc->devices[i];
1347 			if (dev->driver == driver && dev->parent &&
1348 			    dev->parent->devclass == busclass) {
1349 				if ((error = device_quiesce(dev)) != 0)
1350 					return (error);
1351 			}
1352 		}
1353 	}
1354 
1355 	return (0);
1356 }
1357 
1358 /**
1359  * @internal
1360  */
1361 static driverlink_t
1362 devclass_find_driver_internal(devclass_t dc, const char *classname)
1363 {
1364 	driverlink_t dl;
1365 
1366 	PDEBUG(("%s in devclass %s", classname, DEVCLANAME(dc)));
1367 
1368 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1369 		if (!strcmp(dl->driver->name, classname))
1370 			return (dl);
1371 	}
1372 
1373 	PDEBUG(("not found"));
1374 	return (NULL);
1375 }
1376 
1377 /**
1378  * @brief Return the name of the devclass
1379  */
1380 const char *
1381 devclass_get_name(devclass_t dc)
1382 {
1383 	return (dc->name);
1384 }
1385 
1386 /**
1387  * @brief Find a device given a unit number
1388  *
1389  * @param dc		the devclass to search
1390  * @param unit		the unit number to search for
1391  *
1392  * @returns		the device with the given unit number or @c
1393  *			NULL if there is no such device
1394  */
1395 device_t
1396 devclass_get_device(devclass_t dc, int unit)
1397 {
1398 	if (dc == NULL || unit < 0 || unit >= dc->maxunit)
1399 		return (NULL);
1400 	return (dc->devices[unit]);
1401 }
1402 
1403 /**
1404  * @brief Find the softc field of a device given a unit number
1405  *
1406  * @param dc		the devclass to search
1407  * @param unit		the unit number to search for
1408  *
1409  * @returns		the softc field of the device with the given
1410  *			unit number or @c NULL if there is no such
1411  *			device
1412  */
1413 void *
1414 devclass_get_softc(devclass_t dc, int unit)
1415 {
1416 	device_t dev;
1417 
1418 	dev = devclass_get_device(dc, unit);
1419 	if (!dev)
1420 		return (NULL);
1421 
1422 	return (device_get_softc(dev));
1423 }
1424 
1425 /**
1426  * @brief Get a list of devices in the devclass
1427  *
1428  * An array containing a list of all the devices in the given devclass
1429  * is allocated and returned in @p *devlistp. The number of devices
1430  * in the array is returned in @p *devcountp. The caller should free
1431  * the array using @c free(p, M_TEMP), even if @p *devcountp is 0.
1432  *
1433  * @param dc		the devclass to examine
1434  * @param devlistp	points at location for array pointer return
1435  *			value
1436  * @param devcountp	points at location for array size return value
1437  *
1438  * @retval 0		success
1439  * @retval ENOMEM	the array allocation failed
1440  */
1441 int
1442 devclass_get_devices(devclass_t dc, device_t **devlistp, int *devcountp)
1443 {
1444 	int count, i;
1445 	device_t *list;
1446 
1447 	count = devclass_get_count(dc);
1448 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
1449 	if (!list)
1450 		return (ENOMEM);
1451 
1452 	count = 0;
1453 	for (i = 0; i < dc->maxunit; i++) {
1454 		if (dc->devices[i]) {
1455 			list[count] = dc->devices[i];
1456 			count++;
1457 		}
1458 	}
1459 
1460 	*devlistp = list;
1461 	*devcountp = count;
1462 
1463 	return (0);
1464 }
1465 
1466 /**
1467  * @brief Get a list of drivers in the devclass
1468  *
1469  * An array containing a list of pointers to all the drivers in the
1470  * given devclass is allocated and returned in @p *listp.  The number
1471  * of drivers in the array is returned in @p *countp. The caller should
1472  * free the array using @c free(p, M_TEMP).
1473  *
1474  * @param dc		the devclass to examine
1475  * @param listp		gives location for array pointer return value
1476  * @param countp	gives location for number of array elements
1477  *			return value
1478  *
1479  * @retval 0		success
1480  * @retval ENOMEM	the array allocation failed
1481  */
1482 int
1483 devclass_get_drivers(devclass_t dc, driver_t ***listp, int *countp)
1484 {
1485 	driverlink_t dl;
1486 	driver_t **list;
1487 	int count;
1488 
1489 	count = 0;
1490 	TAILQ_FOREACH(dl, &dc->drivers, link)
1491 		count++;
1492 	list = malloc(count * sizeof(driver_t *), M_TEMP, M_NOWAIT);
1493 	if (list == NULL)
1494 		return (ENOMEM);
1495 
1496 	count = 0;
1497 	TAILQ_FOREACH(dl, &dc->drivers, link) {
1498 		list[count] = dl->driver;
1499 		count++;
1500 	}
1501 	*listp = list;
1502 	*countp = count;
1503 
1504 	return (0);
1505 }
1506 
1507 /**
1508  * @brief Get the number of devices in a devclass
1509  *
1510  * @param dc		the devclass to examine
1511  */
1512 int
1513 devclass_get_count(devclass_t dc)
1514 {
1515 	int count, i;
1516 
1517 	count = 0;
1518 	for (i = 0; i < dc->maxunit; i++)
1519 		if (dc->devices[i])
1520 			count++;
1521 	return (count);
1522 }
1523 
1524 /**
1525  * @brief Get the maximum unit number used in a devclass
1526  *
1527  * Note that this is one greater than the highest currently-allocated
1528  * unit.  If a null devclass_t is passed in, -1 is returned to indicate
1529  * that not even the devclass has been allocated yet.
1530  *
1531  * @param dc		the devclass to examine
1532  */
1533 int
1534 devclass_get_maxunit(devclass_t dc)
1535 {
1536 	if (dc == NULL)
1537 		return (-1);
1538 	return (dc->maxunit);
1539 }
1540 
1541 /**
1542  * @brief Find a free unit number in a devclass
1543  *
1544  * This function searches for the first unused unit number greater
1545  * that or equal to @p unit.
1546  *
1547  * @param dc		the devclass to examine
1548  * @param unit		the first unit number to check
1549  */
1550 int
1551 devclass_find_free_unit(devclass_t dc, int unit)
1552 {
1553 	if (dc == NULL)
1554 		return (unit);
1555 	while (unit < dc->maxunit && dc->devices[unit] != NULL)
1556 		unit++;
1557 	return (unit);
1558 }
1559 
1560 /**
1561  * @brief Set the parent of a devclass
1562  *
1563  * The parent class is normally initialised automatically by
1564  * DRIVER_MODULE().
1565  *
1566  * @param dc		the devclass to edit
1567  * @param pdc		the new parent devclass
1568  */
1569 void
1570 devclass_set_parent(devclass_t dc, devclass_t pdc)
1571 {
1572 	dc->parent = pdc;
1573 }
1574 
1575 /**
1576  * @brief Get the parent of a devclass
1577  *
1578  * @param dc		the devclass to examine
1579  */
1580 devclass_t
1581 devclass_get_parent(devclass_t dc)
1582 {
1583 	return (dc->parent);
1584 }
1585 
1586 struct sysctl_ctx_list *
1587 devclass_get_sysctl_ctx(devclass_t dc)
1588 {
1589 	return (&dc->sysctl_ctx);
1590 }
1591 
1592 struct sysctl_oid *
1593 devclass_get_sysctl_tree(devclass_t dc)
1594 {
1595 	return (dc->sysctl_tree);
1596 }
1597 
1598 /**
1599  * @internal
1600  * @brief Allocate a unit number
1601  *
1602  * On entry, @p *unitp is the desired unit number (or @c -1 if any
1603  * will do). The allocated unit number is returned in @p *unitp.
1604 
1605  * @param dc		the devclass to allocate from
1606  * @param unitp		points at the location for the allocated unit
1607  *			number
1608  *
1609  * @retval 0		success
1610  * @retval EEXIST	the requested unit number is already allocated
1611  * @retval ENOMEM	memory allocation failure
1612  */
1613 static int
1614 devclass_alloc_unit(devclass_t dc, device_t dev, int *unitp)
1615 {
1616 	const char *s;
1617 	int unit = *unitp;
1618 
1619 	PDEBUG(("unit %d in devclass %s", unit, DEVCLANAME(dc)));
1620 
1621 	/* Ask the parent bus if it wants to wire this device. */
1622 	if (unit == -1)
1623 		BUS_HINT_DEVICE_UNIT(device_get_parent(dev), dev, dc->name,
1624 		    &unit);
1625 
1626 	/* If we were given a wired unit number, check for existing device */
1627 	/* XXX imp XXX */
1628 	if (unit != -1) {
1629 		if (unit >= 0 && unit < dc->maxunit &&
1630 		    dc->devices[unit] != NULL) {
1631 			if (bootverbose)
1632 				printf("%s: %s%d already exists; skipping it\n",
1633 				    dc->name, dc->name, *unitp);
1634 			return (EEXIST);
1635 		}
1636 	} else {
1637 		/* Unwired device, find the next available slot for it */
1638 		unit = 0;
1639 		for (unit = 0;; unit++) {
1640 			/* If there is an "at" hint for a unit then skip it. */
1641 			if (resource_string_value(dc->name, unit, "at", &s) ==
1642 			    0)
1643 				continue;
1644 
1645 			/* If this device slot is already in use, skip it. */
1646 			if (unit < dc->maxunit && dc->devices[unit] != NULL)
1647 				continue;
1648 
1649 			break;
1650 		}
1651 	}
1652 
1653 	/*
1654 	 * We've selected a unit beyond the length of the table, so let's
1655 	 * extend the table to make room for all units up to and including
1656 	 * this one.
1657 	 */
1658 	if (unit >= dc->maxunit) {
1659 		device_t *newlist, *oldlist;
1660 		int newsize;
1661 
1662 		oldlist = dc->devices;
1663 		newsize = roundup((unit + 1),
1664 		    MAX(1, MINALLOCSIZE / sizeof(device_t)));
1665 		newlist = malloc(sizeof(device_t) * newsize, M_BUS, M_NOWAIT);
1666 		if (!newlist)
1667 			return (ENOMEM);
1668 		if (oldlist != NULL)
1669 			bcopy(oldlist, newlist, sizeof(device_t) * dc->maxunit);
1670 		bzero(newlist + dc->maxunit,
1671 		    sizeof(device_t) * (newsize - dc->maxunit));
1672 		dc->devices = newlist;
1673 		dc->maxunit = newsize;
1674 		if (oldlist != NULL)
1675 			free(oldlist, M_BUS);
1676 	}
1677 	PDEBUG(("now: unit %d in devclass %s", unit, DEVCLANAME(dc)));
1678 
1679 	*unitp = unit;
1680 	return (0);
1681 }
1682 
1683 /**
1684  * @internal
1685  * @brief Add a device to a devclass
1686  *
1687  * A unit number is allocated for the device (using the device's
1688  * preferred unit number if any) and the device is registered in the
1689  * devclass. This allows the device to be looked up by its unit
1690  * number, e.g. by decoding a dev_t minor number.
1691  *
1692  * @param dc		the devclass to add to
1693  * @param dev		the device to add
1694  *
1695  * @retval 0		success
1696  * @retval EEXIST	the requested unit number is already allocated
1697  * @retval ENOMEM	memory allocation failure
1698  */
1699 static int
1700 devclass_add_device(devclass_t dc, device_t dev)
1701 {
1702 	int buflen, error;
1703 
1704 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1705 
1706 	buflen = snprintf(NULL, 0, "%s%d$", dc->name, INT_MAX);
1707 	if (buflen < 0)
1708 		return (ENOMEM);
1709 	dev->nameunit = malloc(buflen, M_BUS, M_NOWAIT|M_ZERO);
1710 	if (!dev->nameunit)
1711 		return (ENOMEM);
1712 
1713 	if ((error = devclass_alloc_unit(dc, dev, &dev->unit)) != 0) {
1714 		free(dev->nameunit, M_BUS);
1715 		dev->nameunit = NULL;
1716 		return (error);
1717 	}
1718 	dc->devices[dev->unit] = dev;
1719 	dev->devclass = dc;
1720 	snprintf(dev->nameunit, buflen, "%s%d", dc->name, dev->unit);
1721 
1722 	return (0);
1723 }
1724 
1725 /**
1726  * @internal
1727  * @brief Delete a device from a devclass
1728  *
1729  * The device is removed from the devclass's device list and its unit
1730  * number is freed.
1731 
1732  * @param dc		the devclass to delete from
1733  * @param dev		the device to delete
1734  *
1735  * @retval 0		success
1736  */
1737 static int
1738 devclass_delete_device(devclass_t dc, device_t dev)
1739 {
1740 	if (!dc || !dev)
1741 		return (0);
1742 
1743 	PDEBUG(("%s in devclass %s", DEVICENAME(dev), DEVCLANAME(dc)));
1744 
1745 	if (dev->devclass != dc || dc->devices[dev->unit] != dev)
1746 		panic("devclass_delete_device: inconsistent device class");
1747 	dc->devices[dev->unit] = NULL;
1748 	if (dev->flags & DF_WILDCARD)
1749 		dev->unit = -1;
1750 	dev->devclass = NULL;
1751 	free(dev->nameunit, M_BUS);
1752 	dev->nameunit = NULL;
1753 
1754 	return (0);
1755 }
1756 
1757 /**
1758  * @internal
1759  * @brief Make a new device and add it as a child of @p parent
1760  *
1761  * @param parent	the parent of the new device
1762  * @param name		the devclass name of the new device or @c NULL
1763  *			to leave the devclass unspecified
1764  * @parem unit		the unit number of the new device of @c -1 to
1765  *			leave the unit number unspecified
1766  *
1767  * @returns the new device
1768  */
1769 static device_t
1770 make_device(device_t parent, const char *name, int unit)
1771 {
1772 	device_t dev;
1773 	devclass_t dc;
1774 
1775 	PDEBUG(("%s at %s as unit %d", name, DEVICENAME(parent), unit));
1776 
1777 	if (name) {
1778 		dc = devclass_find_internal(name, NULL, TRUE);
1779 		if (!dc) {
1780 			printf("make_device: can't find device class %s\n",
1781 			    name);
1782 			return (NULL);
1783 		}
1784 	} else {
1785 		dc = NULL;
1786 	}
1787 
1788 	dev = malloc(sizeof(*dev), M_BUS, M_NOWAIT|M_ZERO);
1789 	if (!dev)
1790 		return (NULL);
1791 
1792 	dev->parent = parent;
1793 	TAILQ_INIT(&dev->children);
1794 	kobj_init((kobj_t) dev, &null_class);
1795 	dev->driver = NULL;
1796 	dev->devclass = NULL;
1797 	dev->unit = unit;
1798 	dev->nameunit = NULL;
1799 	dev->desc = NULL;
1800 	dev->busy = 0;
1801 	dev->devflags = 0;
1802 	dev->flags = DF_ENABLED;
1803 	dev->order = 0;
1804 	if (unit == -1)
1805 		dev->flags |= DF_WILDCARD;
1806 	if (name) {
1807 		dev->flags |= DF_FIXEDCLASS;
1808 		if (devclass_add_device(dc, dev)) {
1809 			kobj_delete((kobj_t) dev, M_BUS);
1810 			return (NULL);
1811 		}
1812 	}
1813 	if (parent != NULL && device_has_quiet_children(parent))
1814 		dev->flags |= DF_QUIET | DF_QUIET_CHILDREN;
1815 	dev->ivars = NULL;
1816 	dev->softc = NULL;
1817 
1818 	dev->state = DS_NOTPRESENT;
1819 
1820 	TAILQ_INSERT_TAIL(&bus_data_devices, dev, devlink);
1821 	bus_data_generation_update();
1822 
1823 	return (dev);
1824 }
1825 
1826 /**
1827  * @internal
1828  * @brief Print a description of a device.
1829  */
1830 static int
1831 device_print_child(device_t dev, device_t child)
1832 {
1833 	int retval = 0;
1834 
1835 	if (device_is_alive(child))
1836 		retval += BUS_PRINT_CHILD(dev, child);
1837 	else
1838 		retval += device_printf(child, " not found\n");
1839 
1840 	return (retval);
1841 }
1842 
1843 /**
1844  * @brief Create a new device
1845  *
1846  * This creates a new device and adds it as a child of an existing
1847  * parent device. The new device will be added after the last existing
1848  * child with order zero.
1849  *
1850  * @param dev		the device which will be the parent of the
1851  *			new child device
1852  * @param name		devclass name for new device or @c NULL if not
1853  *			specified
1854  * @param unit		unit number for new device or @c -1 if not
1855  *			specified
1856  *
1857  * @returns		the new device
1858  */
1859 device_t
1860 device_add_child(device_t dev, const char *name, int unit)
1861 {
1862 	return (device_add_child_ordered(dev, 0, name, unit));
1863 }
1864 
1865 /**
1866  * @brief Create a new device
1867  *
1868  * This creates a new device and adds it as a child of an existing
1869  * parent device. The new device will be added after the last existing
1870  * child with the same order.
1871  *
1872  * @param dev		the device which will be the parent of the
1873  *			new child device
1874  * @param order		a value which is used to partially sort the
1875  *			children of @p dev - devices created using
1876  *			lower values of @p order appear first in @p
1877  *			dev's list of children
1878  * @param name		devclass name for new device or @c NULL if not
1879  *			specified
1880  * @param unit		unit number for new device or @c -1 if not
1881  *			specified
1882  *
1883  * @returns		the new device
1884  */
1885 device_t
1886 device_add_child_ordered(device_t dev, u_int order, const char *name, int unit)
1887 {
1888 	device_t child;
1889 	device_t place;
1890 
1891 	PDEBUG(("%s at %s with order %u as unit %d",
1892 	    name, DEVICENAME(dev), order, unit));
1893 	KASSERT(name != NULL || unit == -1,
1894 	    ("child device with wildcard name and specific unit number"));
1895 
1896 	child = make_device(dev, name, unit);
1897 	if (child == NULL)
1898 		return (child);
1899 	child->order = order;
1900 
1901 	TAILQ_FOREACH(place, &dev->children, link) {
1902 		if (place->order > order)
1903 			break;
1904 	}
1905 
1906 	if (place) {
1907 		/*
1908 		 * The device 'place' is the first device whose order is
1909 		 * greater than the new child.
1910 		 */
1911 		TAILQ_INSERT_BEFORE(place, child, link);
1912 	} else {
1913 		/*
1914 		 * The new child's order is greater or equal to the order of
1915 		 * any existing device. Add the child to the tail of the list.
1916 		 */
1917 		TAILQ_INSERT_TAIL(&dev->children, child, link);
1918 	}
1919 
1920 	bus_data_generation_update();
1921 	return (child);
1922 }
1923 
1924 /**
1925  * @brief Delete a device
1926  *
1927  * This function deletes a device along with all of its children. If
1928  * the device currently has a driver attached to it, the device is
1929  * detached first using device_detach().
1930  *
1931  * @param dev		the parent device
1932  * @param child		the device to delete
1933  *
1934  * @retval 0		success
1935  * @retval non-zero	a unit error code describing the error
1936  */
1937 int
1938 device_delete_child(device_t dev, device_t child)
1939 {
1940 	int error;
1941 	device_t grandchild;
1942 
1943 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
1944 
1945 	/* detach parent before deleting children, if any */
1946 	if ((error = device_detach(child)) != 0)
1947 		return (error);
1948 
1949 	/* remove children second */
1950 	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
1951 		error = device_delete_child(child, grandchild);
1952 		if (error)
1953 			return (error);
1954 	}
1955 
1956 	if (child->devclass)
1957 		devclass_delete_device(child->devclass, child);
1958 	if (child->parent)
1959 		BUS_CHILD_DELETED(dev, child);
1960 	TAILQ_REMOVE(&dev->children, child, link);
1961 	TAILQ_REMOVE(&bus_data_devices, child, devlink);
1962 	kobj_delete((kobj_t) child, M_BUS);
1963 
1964 	bus_data_generation_update();
1965 	return (0);
1966 }
1967 
1968 /**
1969  * @brief Delete all children devices of the given device, if any.
1970  *
1971  * This function deletes all children devices of the given device, if
1972  * any, using the device_delete_child() function for each device it
1973  * finds. If a child device cannot be deleted, this function will
1974  * return an error code.
1975  *
1976  * @param dev		the parent device
1977  *
1978  * @retval 0		success
1979  * @retval non-zero	a device would not detach
1980  */
1981 int
1982 device_delete_children(device_t dev)
1983 {
1984 	device_t child;
1985 	int error;
1986 
1987 	PDEBUG(("Deleting all children of %s", DEVICENAME(dev)));
1988 
1989 	error = 0;
1990 
1991 	while ((child = TAILQ_FIRST(&dev->children)) != NULL) {
1992 		error = device_delete_child(dev, child);
1993 		if (error) {
1994 			PDEBUG(("Failed deleting %s", DEVICENAME(child)));
1995 			break;
1996 		}
1997 	}
1998 	return (error);
1999 }
2000 
2001 /**
2002  * @brief Find a device given a unit number
2003  *
2004  * This is similar to devclass_get_devices() but only searches for
2005  * devices which have @p dev as a parent.
2006  *
2007  * @param dev		the parent device to search
2008  * @param unit		the unit number to search for.  If the unit is -1,
2009  *			return the first child of @p dev which has name
2010  *			@p classname (that is, the one with the lowest unit.)
2011  *
2012  * @returns		the device with the given unit number or @c
2013  *			NULL if there is no such device
2014  */
2015 device_t
2016 device_find_child(device_t dev, const char *classname, int unit)
2017 {
2018 	devclass_t dc;
2019 	device_t child;
2020 
2021 	dc = devclass_find(classname);
2022 	if (!dc)
2023 		return (NULL);
2024 
2025 	if (unit != -1) {
2026 		child = devclass_get_device(dc, unit);
2027 		if (child && child->parent == dev)
2028 			return (child);
2029 	} else {
2030 		for (unit = 0; unit < devclass_get_maxunit(dc); unit++) {
2031 			child = devclass_get_device(dc, unit);
2032 			if (child && child->parent == dev)
2033 				return (child);
2034 		}
2035 	}
2036 	return (NULL);
2037 }
2038 
2039 /**
2040  * @internal
2041  */
2042 static driverlink_t
2043 first_matching_driver(devclass_t dc, device_t dev)
2044 {
2045 	if (dev->devclass)
2046 		return (devclass_find_driver_internal(dc, dev->devclass->name));
2047 	return (TAILQ_FIRST(&dc->drivers));
2048 }
2049 
2050 /**
2051  * @internal
2052  */
2053 static driverlink_t
2054 next_matching_driver(devclass_t dc, device_t dev, driverlink_t last)
2055 {
2056 	if (dev->devclass) {
2057 		driverlink_t dl;
2058 		for (dl = TAILQ_NEXT(last, link); dl; dl = TAILQ_NEXT(dl, link))
2059 			if (!strcmp(dev->devclass->name, dl->driver->name))
2060 				return (dl);
2061 		return (NULL);
2062 	}
2063 	return (TAILQ_NEXT(last, link));
2064 }
2065 
2066 /**
2067  * @internal
2068  */
2069 int
2070 device_probe_child(device_t dev, device_t child)
2071 {
2072 	devclass_t dc;
2073 	driverlink_t best = NULL;
2074 	driverlink_t dl;
2075 	int result, pri = 0;
2076 	int hasclass = (child->devclass != NULL);
2077 
2078 	GIANT_REQUIRED;
2079 
2080 	dc = dev->devclass;
2081 	if (!dc)
2082 		panic("device_probe_child: parent device has no devclass");
2083 
2084 	/*
2085 	 * If the state is already probed, then return.  However, don't
2086 	 * return if we can rebid this object.
2087 	 */
2088 	if (child->state == DS_ALIVE && (child->flags & DF_REBID) == 0)
2089 		return (0);
2090 
2091 	for (; dc; dc = dc->parent) {
2092 		for (dl = first_matching_driver(dc, child);
2093 		     dl;
2094 		     dl = next_matching_driver(dc, child, dl)) {
2095 			/* If this driver's pass is too high, then ignore it. */
2096 			if (dl->pass > bus_current_pass)
2097 				continue;
2098 
2099 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
2100 			result = device_set_driver(child, dl->driver);
2101 			if (result == ENOMEM)
2102 				return (result);
2103 			else if (result != 0)
2104 				continue;
2105 			if (!hasclass) {
2106 				if (device_set_devclass(child,
2107 				    dl->driver->name) != 0) {
2108 					char const * devname =
2109 					    device_get_name(child);
2110 					if (devname == NULL)
2111 						devname = "(unknown)";
2112 					printf("driver bug: Unable to set "
2113 					    "devclass (class: %s "
2114 					    "devname: %s)\n",
2115 					    dl->driver->name,
2116 					    devname);
2117 					(void)device_set_driver(child, NULL);
2118 					continue;
2119 				}
2120 			}
2121 
2122 			/* Fetch any flags for the device before probing. */
2123 			resource_int_value(dl->driver->name, child->unit,
2124 			    "flags", &child->devflags);
2125 
2126 			result = DEVICE_PROBE(child);
2127 
2128 			/* Reset flags and devclass before the next probe. */
2129 			child->devflags = 0;
2130 			if (!hasclass)
2131 				(void)device_set_devclass(child, NULL);
2132 
2133 			/*
2134 			 * If the driver returns SUCCESS, there can be
2135 			 * no higher match for this device.
2136 			 */
2137 			if (result == 0) {
2138 				best = dl;
2139 				pri = 0;
2140 				break;
2141 			}
2142 
2143 			/*
2144 			 * Reset DF_QUIET in case this driver doesn't
2145 			 * end up as the best driver.
2146 			 */
2147 			device_verbose(child);
2148 
2149 			/*
2150 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
2151 			 * only match on devices whose driver was explicitly
2152 			 * specified.
2153 			 */
2154 			if (result <= BUS_PROBE_NOWILDCARD &&
2155 			    !(child->flags & DF_FIXEDCLASS)) {
2156 				result = ENXIO;
2157 			}
2158 
2159 			/*
2160 			 * The driver returned an error so it
2161 			 * certainly doesn't match.
2162 			 */
2163 			if (result > 0) {
2164 				(void)device_set_driver(child, NULL);
2165 				continue;
2166 			}
2167 
2168 			/*
2169 			 * A priority lower than SUCCESS, remember the
2170 			 * best matching driver. Initialise the value
2171 			 * of pri for the first match.
2172 			 */
2173 			if (best == NULL || result > pri) {
2174 				best = dl;
2175 				pri = result;
2176 				continue;
2177 			}
2178 		}
2179 		/*
2180 		 * If we have an unambiguous match in this devclass,
2181 		 * don't look in the parent.
2182 		 */
2183 		if (best && pri == 0)
2184 			break;
2185 	}
2186 
2187 	/*
2188 	 * If we found a driver, change state and initialise the devclass.
2189 	 */
2190 	/* XXX What happens if we rebid and got no best? */
2191 	if (best) {
2192 		/*
2193 		 * If this device was attached, and we were asked to
2194 		 * rescan, and it is a different driver, then we have
2195 		 * to detach the old driver and reattach this new one.
2196 		 * Note, we don't have to check for DF_REBID here
2197 		 * because if the state is > DS_ALIVE, we know it must
2198 		 * be.
2199 		 *
2200 		 * This assumes that all DF_REBID drivers can have
2201 		 * their probe routine called at any time and that
2202 		 * they are idempotent as well as completely benign in
2203 		 * normal operations.
2204 		 *
2205 		 * We also have to make sure that the detach
2206 		 * succeeded, otherwise we fail the operation (or
2207 		 * maybe it should just fail silently?  I'm torn).
2208 		 */
2209 		if (child->state > DS_ALIVE && best->driver != child->driver)
2210 			if ((result = device_detach(dev)) != 0)
2211 				return (result);
2212 
2213 		/* Set the winning driver, devclass, and flags. */
2214 		if (!child->devclass) {
2215 			result = device_set_devclass(child, best->driver->name);
2216 			if (result != 0)
2217 				return (result);
2218 		}
2219 		result = device_set_driver(child, best->driver);
2220 		if (result != 0)
2221 			return (result);
2222 		resource_int_value(best->driver->name, child->unit,
2223 		    "flags", &child->devflags);
2224 
2225 		if (pri < 0) {
2226 			/*
2227 			 * A bit bogus. Call the probe method again to make
2228 			 * sure that we have the right description.
2229 			 */
2230 			DEVICE_PROBE(child);
2231 #if 0
2232 			child->flags |= DF_REBID;
2233 #endif
2234 		} else
2235 			child->flags &= ~DF_REBID;
2236 		child->state = DS_ALIVE;
2237 
2238 		bus_data_generation_update();
2239 		return (0);
2240 	}
2241 
2242 	return (ENXIO);
2243 }
2244 
2245 /**
2246  * @brief Return the parent of a device
2247  */
2248 device_t
2249 device_get_parent(device_t dev)
2250 {
2251 	return (dev->parent);
2252 }
2253 
2254 /**
2255  * @brief Get a list of children of a device
2256  *
2257  * An array containing a list of all the children of the given device
2258  * is allocated and returned in @p *devlistp. The number of devices
2259  * in the array is returned in @p *devcountp. The caller should free
2260  * the array using @c free(p, M_TEMP).
2261  *
2262  * @param dev		the device to examine
2263  * @param devlistp	points at location for array pointer return
2264  *			value
2265  * @param devcountp	points at location for array size return value
2266  *
2267  * @retval 0		success
2268  * @retval ENOMEM	the array allocation failed
2269  */
2270 int
2271 device_get_children(device_t dev, device_t **devlistp, int *devcountp)
2272 {
2273 	int count;
2274 	device_t child;
2275 	device_t *list;
2276 
2277 	count = 0;
2278 	TAILQ_FOREACH(child, &dev->children, link) {
2279 		count++;
2280 	}
2281 	if (count == 0) {
2282 		*devlistp = NULL;
2283 		*devcountp = 0;
2284 		return (0);
2285 	}
2286 
2287 	list = malloc(count * sizeof(device_t), M_TEMP, M_NOWAIT|M_ZERO);
2288 	if (!list)
2289 		return (ENOMEM);
2290 
2291 	count = 0;
2292 	TAILQ_FOREACH(child, &dev->children, link) {
2293 		list[count] = child;
2294 		count++;
2295 	}
2296 
2297 	*devlistp = list;
2298 	*devcountp = count;
2299 
2300 	return (0);
2301 }
2302 
2303 /**
2304  * @brief Return the current driver for the device or @c NULL if there
2305  * is no driver currently attached
2306  */
2307 driver_t *
2308 device_get_driver(device_t dev)
2309 {
2310 	return (dev->driver);
2311 }
2312 
2313 /**
2314  * @brief Return the current devclass for the device or @c NULL if
2315  * there is none.
2316  */
2317 devclass_t
2318 device_get_devclass(device_t dev)
2319 {
2320 	return (dev->devclass);
2321 }
2322 
2323 /**
2324  * @brief Return the name of the device's devclass or @c NULL if there
2325  * is none.
2326  */
2327 const char *
2328 device_get_name(device_t dev)
2329 {
2330 	if (dev != NULL && dev->devclass)
2331 		return (devclass_get_name(dev->devclass));
2332 	return (NULL);
2333 }
2334 
2335 /**
2336  * @brief Return a string containing the device's devclass name
2337  * followed by an ascii representation of the device's unit number
2338  * (e.g. @c "foo2").
2339  */
2340 const char *
2341 device_get_nameunit(device_t dev)
2342 {
2343 	return (dev->nameunit);
2344 }
2345 
2346 /**
2347  * @brief Return the device's unit number.
2348  */
2349 int
2350 device_get_unit(device_t dev)
2351 {
2352 	return (dev->unit);
2353 }
2354 
2355 /**
2356  * @brief Return the device's description string
2357  */
2358 const char *
2359 device_get_desc(device_t dev)
2360 {
2361 	return (dev->desc);
2362 }
2363 
2364 /**
2365  * @brief Return the device's flags
2366  */
2367 uint32_t
2368 device_get_flags(device_t dev)
2369 {
2370 	return (dev->devflags);
2371 }
2372 
2373 struct sysctl_ctx_list *
2374 device_get_sysctl_ctx(device_t dev)
2375 {
2376 	return (&dev->sysctl_ctx);
2377 }
2378 
2379 struct sysctl_oid *
2380 device_get_sysctl_tree(device_t dev)
2381 {
2382 	return (dev->sysctl_tree);
2383 }
2384 
2385 /**
2386  * @brief Print the name of the device followed by a colon and a space
2387  *
2388  * @returns the number of characters printed
2389  */
2390 int
2391 device_print_prettyname(device_t dev)
2392 {
2393 	const char *name = device_get_name(dev);
2394 
2395 	if (name == NULL)
2396 		return (printf("unknown: "));
2397 	return (printf("%s%d: ", name, device_get_unit(dev)));
2398 }
2399 
2400 /**
2401  * @brief Print the name of the device followed by a colon, a space
2402  * and the result of calling vprintf() with the value of @p fmt and
2403  * the following arguments.
2404  *
2405  * @returns the number of characters printed
2406  */
2407 int
2408 device_printf(device_t dev, const char * fmt, ...)
2409 {
2410 	char buf[128];
2411 	struct sbuf sb;
2412 	const char *name;
2413 	va_list ap;
2414 	size_t retval;
2415 
2416 	retval = 0;
2417 
2418 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2419 	sbuf_set_drain(&sb, sbuf_printf_drain, &retval);
2420 
2421 	name = device_get_name(dev);
2422 
2423 	if (name == NULL)
2424 		sbuf_cat(&sb, "unknown: ");
2425 	else
2426 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2427 
2428 	va_start(ap, fmt);
2429 	sbuf_vprintf(&sb, fmt, ap);
2430 	va_end(ap);
2431 
2432 	sbuf_finish(&sb);
2433 	sbuf_delete(&sb);
2434 
2435 	return (retval);
2436 }
2437 
2438 /**
2439  * @brief Print the name of the device followed by a colon, a space
2440  * and the result of calling log() with the value of @p fmt and
2441  * the following arguments.
2442  *
2443  * @returns the number of characters printed
2444  */
2445 int
2446 device_log(device_t dev, int pri, const char * fmt, ...)
2447 {
2448 	char buf[128];
2449 	struct sbuf sb;
2450 	const char *name;
2451 	va_list ap;
2452 	size_t retval;
2453 
2454 	retval = 0;
2455 
2456 	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
2457 
2458 	name = device_get_name(dev);
2459 
2460 	if (name == NULL)
2461 		sbuf_cat(&sb, "unknown: ");
2462 	else
2463 		sbuf_printf(&sb, "%s%d: ", name, device_get_unit(dev));
2464 
2465 	va_start(ap, fmt);
2466 	sbuf_vprintf(&sb, fmt, ap);
2467 	va_end(ap);
2468 
2469 	sbuf_finish(&sb);
2470 
2471 	log(pri, "%.*s", (int) sbuf_len(&sb), sbuf_data(&sb));
2472 	retval = sbuf_len(&sb);
2473 
2474 	sbuf_delete(&sb);
2475 
2476 	return (retval);
2477 }
2478 
2479 /**
2480  * @internal
2481  */
2482 static void
2483 device_set_desc_internal(device_t dev, const char* desc, int copy)
2484 {
2485 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
2486 		free(dev->desc, M_BUS);
2487 		dev->flags &= ~DF_DESCMALLOCED;
2488 		dev->desc = NULL;
2489 	}
2490 
2491 	if (copy && desc) {
2492 		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
2493 		if (dev->desc) {
2494 			strcpy(dev->desc, desc);
2495 			dev->flags |= DF_DESCMALLOCED;
2496 		}
2497 	} else {
2498 		/* Avoid a -Wcast-qual warning */
2499 		dev->desc = (char *)(uintptr_t) desc;
2500 	}
2501 
2502 	bus_data_generation_update();
2503 }
2504 
2505 /**
2506  * @brief Set the device's description
2507  *
2508  * The value of @c desc should be a string constant that will not
2509  * change (at least until the description is changed in a subsequent
2510  * call to device_set_desc() or device_set_desc_copy()).
2511  */
2512 void
2513 device_set_desc(device_t dev, const char* desc)
2514 {
2515 	device_set_desc_internal(dev, desc, FALSE);
2516 }
2517 
2518 /**
2519  * @brief Set the device's description
2520  *
2521  * The string pointed to by @c desc is copied. Use this function if
2522  * the device description is generated, (e.g. with sprintf()).
2523  */
2524 void
2525 device_set_desc_copy(device_t dev, const char* desc)
2526 {
2527 	device_set_desc_internal(dev, desc, TRUE);
2528 }
2529 
2530 /**
2531  * @brief Set the device's flags
2532  */
2533 void
2534 device_set_flags(device_t dev, uint32_t flags)
2535 {
2536 	dev->devflags = flags;
2537 }
2538 
2539 /**
2540  * @brief Return the device's softc field
2541  *
2542  * The softc is allocated and zeroed when a driver is attached, based
2543  * on the size field of the driver.
2544  */
2545 void *
2546 device_get_softc(device_t dev)
2547 {
2548 	return (dev->softc);
2549 }
2550 
2551 /**
2552  * @brief Set the device's softc field
2553  *
2554  * Most drivers do not need to use this since the softc is allocated
2555  * automatically when the driver is attached.
2556  */
2557 void
2558 device_set_softc(device_t dev, void *softc)
2559 {
2560 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC))
2561 		free(dev->softc, M_BUS_SC);
2562 	dev->softc = softc;
2563 	if (dev->softc)
2564 		dev->flags |= DF_EXTERNALSOFTC;
2565 	else
2566 		dev->flags &= ~DF_EXTERNALSOFTC;
2567 }
2568 
2569 /**
2570  * @brief Free claimed softc
2571  *
2572  * Most drivers do not need to use this since the softc is freed
2573  * automatically when the driver is detached.
2574  */
2575 void
2576 device_free_softc(void *softc)
2577 {
2578 	free(softc, M_BUS_SC);
2579 }
2580 
2581 /**
2582  * @brief Claim softc
2583  *
2584  * This function can be used to let the driver free the automatically
2585  * allocated softc using "device_free_softc()". This function is
2586  * useful when the driver is refcounting the softc and the softc
2587  * cannot be freed when the "device_detach" method is called.
2588  */
2589 void
2590 device_claim_softc(device_t dev)
2591 {
2592 	if (dev->softc)
2593 		dev->flags |= DF_EXTERNALSOFTC;
2594 	else
2595 		dev->flags &= ~DF_EXTERNALSOFTC;
2596 }
2597 
2598 /**
2599  * @brief Get the device's ivars field
2600  *
2601  * The ivars field is used by the parent device to store per-device
2602  * state (e.g. the physical location of the device or a list of
2603  * resources).
2604  */
2605 void *
2606 device_get_ivars(device_t dev)
2607 {
2608 	KASSERT(dev != NULL, ("device_get_ivars(NULL, ...)"));
2609 	return (dev->ivars);
2610 }
2611 
2612 /**
2613  * @brief Set the device's ivars field
2614  */
2615 void
2616 device_set_ivars(device_t dev, void * ivars)
2617 {
2618 	KASSERT(dev != NULL, ("device_set_ivars(NULL, ...)"));
2619 	dev->ivars = ivars;
2620 }
2621 
2622 /**
2623  * @brief Return the device's state
2624  */
2625 device_state_t
2626 device_get_state(device_t dev)
2627 {
2628 	return (dev->state);
2629 }
2630 
2631 /**
2632  * @brief Set the DF_ENABLED flag for the device
2633  */
2634 void
2635 device_enable(device_t dev)
2636 {
2637 	dev->flags |= DF_ENABLED;
2638 }
2639 
2640 /**
2641  * @brief Clear the DF_ENABLED flag for the device
2642  */
2643 void
2644 device_disable(device_t dev)
2645 {
2646 	dev->flags &= ~DF_ENABLED;
2647 }
2648 
2649 /**
2650  * @brief Increment the busy counter for the device
2651  */
2652 void
2653 device_busy(device_t dev)
2654 {
2655 	if (dev->state < DS_ATTACHING)
2656 		panic("device_busy: called for unattached device");
2657 	if (dev->busy == 0 && dev->parent)
2658 		device_busy(dev->parent);
2659 	dev->busy++;
2660 	if (dev->state == DS_ATTACHED)
2661 		dev->state = DS_BUSY;
2662 }
2663 
2664 /**
2665  * @brief Decrement the busy counter for the device
2666  */
2667 void
2668 device_unbusy(device_t dev)
2669 {
2670 	if (dev->busy != 0 && dev->state != DS_BUSY &&
2671 	    dev->state != DS_ATTACHING)
2672 		panic("device_unbusy: called for non-busy device %s",
2673 		    device_get_nameunit(dev));
2674 	dev->busy--;
2675 	if (dev->busy == 0) {
2676 		if (dev->parent)
2677 			device_unbusy(dev->parent);
2678 		if (dev->state == DS_BUSY)
2679 			dev->state = DS_ATTACHED;
2680 	}
2681 }
2682 
2683 /**
2684  * @brief Set the DF_QUIET flag for the device
2685  */
2686 void
2687 device_quiet(device_t dev)
2688 {
2689 	dev->flags |= DF_QUIET;
2690 }
2691 
2692 /**
2693  * @brief Set the DF_QUIET_CHILDREN flag for the device
2694  */
2695 void
2696 device_quiet_children(device_t dev)
2697 {
2698 	dev->flags |= DF_QUIET_CHILDREN;
2699 }
2700 
2701 /**
2702  * @brief Clear the DF_QUIET flag for the device
2703  */
2704 void
2705 device_verbose(device_t dev)
2706 {
2707 	dev->flags &= ~DF_QUIET;
2708 }
2709 
2710 /**
2711  * @brief Return non-zero if the DF_QUIET_CHIDLREN flag is set on the device
2712  */
2713 int
2714 device_has_quiet_children(device_t dev)
2715 {
2716 	return ((dev->flags & DF_QUIET_CHILDREN) != 0);
2717 }
2718 
2719 /**
2720  * @brief Return non-zero if the DF_QUIET flag is set on the device
2721  */
2722 int
2723 device_is_quiet(device_t dev)
2724 {
2725 	return ((dev->flags & DF_QUIET) != 0);
2726 }
2727 
2728 /**
2729  * @brief Return non-zero if the DF_ENABLED flag is set on the device
2730  */
2731 int
2732 device_is_enabled(device_t dev)
2733 {
2734 	return ((dev->flags & DF_ENABLED) != 0);
2735 }
2736 
2737 /**
2738  * @brief Return non-zero if the device was successfully probed
2739  */
2740 int
2741 device_is_alive(device_t dev)
2742 {
2743 	return (dev->state >= DS_ALIVE);
2744 }
2745 
2746 /**
2747  * @brief Return non-zero if the device currently has a driver
2748  * attached to it
2749  */
2750 int
2751 device_is_attached(device_t dev)
2752 {
2753 	return (dev->state >= DS_ATTACHED);
2754 }
2755 
2756 /**
2757  * @brief Return non-zero if the device is currently suspended.
2758  */
2759 int
2760 device_is_suspended(device_t dev)
2761 {
2762 	return ((dev->flags & DF_SUSPENDED) != 0);
2763 }
2764 
2765 /**
2766  * @brief Set the devclass of a device
2767  * @see devclass_add_device().
2768  */
2769 int
2770 device_set_devclass(device_t dev, const char *classname)
2771 {
2772 	devclass_t dc;
2773 	int error;
2774 
2775 	if (!classname) {
2776 		if (dev->devclass)
2777 			devclass_delete_device(dev->devclass, dev);
2778 		return (0);
2779 	}
2780 
2781 	if (dev->devclass) {
2782 		printf("device_set_devclass: device class already set\n");
2783 		return (EINVAL);
2784 	}
2785 
2786 	dc = devclass_find_internal(classname, NULL, TRUE);
2787 	if (!dc)
2788 		return (ENOMEM);
2789 
2790 	error = devclass_add_device(dc, dev);
2791 
2792 	bus_data_generation_update();
2793 	return (error);
2794 }
2795 
2796 /**
2797  * @brief Set the devclass of a device and mark the devclass fixed.
2798  * @see device_set_devclass()
2799  */
2800 int
2801 device_set_devclass_fixed(device_t dev, const char *classname)
2802 {
2803 	int error;
2804 
2805 	if (classname == NULL)
2806 		return (EINVAL);
2807 
2808 	error = device_set_devclass(dev, classname);
2809 	if (error)
2810 		return (error);
2811 	dev->flags |= DF_FIXEDCLASS;
2812 	return (0);
2813 }
2814 
2815 /**
2816  * @brief Query the device to determine if it's of a fixed devclass
2817  * @see device_set_devclass_fixed()
2818  */
2819 bool
2820 device_is_devclass_fixed(device_t dev)
2821 {
2822 	return ((dev->flags & DF_FIXEDCLASS) != 0);
2823 }
2824 
2825 /**
2826  * @brief Set the driver of a device
2827  *
2828  * @retval 0		success
2829  * @retval EBUSY	the device already has a driver attached
2830  * @retval ENOMEM	a memory allocation failure occurred
2831  */
2832 int
2833 device_set_driver(device_t dev, driver_t *driver)
2834 {
2835 	int domain;
2836 	struct domainset *policy;
2837 
2838 	if (dev->state >= DS_ATTACHED)
2839 		return (EBUSY);
2840 
2841 	if (dev->driver == driver)
2842 		return (0);
2843 
2844 	if (dev->softc && !(dev->flags & DF_EXTERNALSOFTC)) {
2845 		free(dev->softc, M_BUS_SC);
2846 		dev->softc = NULL;
2847 	}
2848 	device_set_desc(dev, NULL);
2849 	kobj_delete((kobj_t) dev, NULL);
2850 	dev->driver = driver;
2851 	if (driver) {
2852 		kobj_init((kobj_t) dev, (kobj_class_t) driver);
2853 		if (!(dev->flags & DF_EXTERNALSOFTC) && driver->size > 0) {
2854 			if (bus_get_domain(dev, &domain) == 0)
2855 				policy = DOMAINSET_PREF(domain);
2856 			else
2857 				policy = DOMAINSET_RR();
2858 			dev->softc = malloc_domainset(driver->size, M_BUS_SC,
2859 			    policy, M_NOWAIT | M_ZERO);
2860 			if (!dev->softc) {
2861 				kobj_delete((kobj_t) dev, NULL);
2862 				kobj_init((kobj_t) dev, &null_class);
2863 				dev->driver = NULL;
2864 				return (ENOMEM);
2865 			}
2866 		}
2867 	} else {
2868 		kobj_init((kobj_t) dev, &null_class);
2869 	}
2870 
2871 	bus_data_generation_update();
2872 	return (0);
2873 }
2874 
2875 /**
2876  * @brief Probe a device, and return this status.
2877  *
2878  * This function is the core of the device autoconfiguration
2879  * system. Its purpose is to select a suitable driver for a device and
2880  * then call that driver to initialise the hardware appropriately. The
2881  * driver is selected by calling the DEVICE_PROBE() method of a set of
2882  * candidate drivers and then choosing the driver which returned the
2883  * best value. This driver is then attached to the device using
2884  * device_attach().
2885  *
2886  * The set of suitable drivers is taken from the list of drivers in
2887  * the parent device's devclass. If the device was originally created
2888  * with a specific class name (see device_add_child()), only drivers
2889  * with that name are probed, otherwise all drivers in the devclass
2890  * are probed. If no drivers return successful probe values in the
2891  * parent devclass, the search continues in the parent of that
2892  * devclass (see devclass_get_parent()) if any.
2893  *
2894  * @param dev		the device to initialise
2895  *
2896  * @retval 0		success
2897  * @retval ENXIO	no driver was found
2898  * @retval ENOMEM	memory allocation failure
2899  * @retval non-zero	some other unix error code
2900  * @retval -1		Device already attached
2901  */
2902 int
2903 device_probe(device_t dev)
2904 {
2905 	int error;
2906 
2907 	GIANT_REQUIRED;
2908 
2909 	if (dev->state >= DS_ALIVE && (dev->flags & DF_REBID) == 0)
2910 		return (-1);
2911 
2912 	if (!(dev->flags & DF_ENABLED)) {
2913 		if (bootverbose && device_get_name(dev) != NULL) {
2914 			device_print_prettyname(dev);
2915 			printf("not probed (disabled)\n");
2916 		}
2917 		return (-1);
2918 	}
2919 	if ((error = device_probe_child(dev->parent, dev)) != 0) {
2920 		if (bus_current_pass == BUS_PASS_DEFAULT &&
2921 		    !(dev->flags & DF_DONENOMATCH)) {
2922 			BUS_PROBE_NOMATCH(dev->parent, dev);
2923 			devnomatch(dev);
2924 			dev->flags |= DF_DONENOMATCH;
2925 		}
2926 		return (error);
2927 	}
2928 	return (0);
2929 }
2930 
2931 /**
2932  * @brief Probe a device and attach a driver if possible
2933  *
2934  * calls device_probe() and attaches if that was successful.
2935  */
2936 int
2937 device_probe_and_attach(device_t dev)
2938 {
2939 	int error;
2940 
2941 	GIANT_REQUIRED;
2942 
2943 	error = device_probe(dev);
2944 	if (error == -1)
2945 		return (0);
2946 	else if (error != 0)
2947 		return (error);
2948 
2949 	CURVNET_SET_QUIET(vnet0);
2950 	error = device_attach(dev);
2951 	CURVNET_RESTORE();
2952 	return error;
2953 }
2954 
2955 /**
2956  * @brief Attach a device driver to a device
2957  *
2958  * This function is a wrapper around the DEVICE_ATTACH() driver
2959  * method. In addition to calling DEVICE_ATTACH(), it initialises the
2960  * device's sysctl tree, optionally prints a description of the device
2961  * and queues a notification event for user-based device management
2962  * services.
2963  *
2964  * Normally this function is only called internally from
2965  * device_probe_and_attach().
2966  *
2967  * @param dev		the device to initialise
2968  *
2969  * @retval 0		success
2970  * @retval ENXIO	no driver was found
2971  * @retval ENOMEM	memory allocation failure
2972  * @retval non-zero	some other unix error code
2973  */
2974 int
2975 device_attach(device_t dev)
2976 {
2977 	uint64_t attachtime;
2978 	uint16_t attachentropy;
2979 	int error;
2980 
2981 	if (resource_disabled(dev->driver->name, dev->unit)) {
2982 		device_disable(dev);
2983 		if (bootverbose)
2984 			 device_printf(dev, "disabled via hints entry\n");
2985 		return (ENXIO);
2986 	}
2987 
2988 	device_sysctl_init(dev);
2989 	if (!device_is_quiet(dev))
2990 		device_print_child(dev->parent, dev);
2991 	attachtime = get_cyclecount();
2992 	dev->state = DS_ATTACHING;
2993 	if ((error = DEVICE_ATTACH(dev)) != 0) {
2994 		printf("device_attach: %s%d attach returned %d\n",
2995 		    dev->driver->name, dev->unit, error);
2996 		if (!(dev->flags & DF_FIXEDCLASS))
2997 			devclass_delete_device(dev->devclass, dev);
2998 		(void)device_set_driver(dev, NULL);
2999 		device_sysctl_fini(dev);
3000 		KASSERT(dev->busy == 0, ("attach failed but busy"));
3001 		dev->state = DS_NOTPRESENT;
3002 		return (error);
3003 	}
3004 	dev->flags |= DF_ATTACHED_ONCE;
3005 	/* We only need the low bits of this time, but ranges from tens to thousands
3006 	 * have been seen, so keep 2 bytes' worth.
3007 	 */
3008 	attachentropy = (uint16_t)(get_cyclecount() - attachtime);
3009 	random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH);
3010 	device_sysctl_update(dev);
3011 	if (dev->busy)
3012 		dev->state = DS_BUSY;
3013 	else
3014 		dev->state = DS_ATTACHED;
3015 	dev->flags &= ~DF_DONENOMATCH;
3016 	EVENTHANDLER_DIRECT_INVOKE(device_attach, dev);
3017 	devadded(dev);
3018 	return (0);
3019 }
3020 
3021 /**
3022  * @brief Detach a driver from a device
3023  *
3024  * This function is a wrapper around the DEVICE_DETACH() driver
3025  * method. If the call to DEVICE_DETACH() succeeds, it calls
3026  * BUS_CHILD_DETACHED() for the parent of @p dev, queues a
3027  * notification event for user-based device management services and
3028  * cleans up the device's sysctl tree.
3029  *
3030  * @param dev		the device to un-initialise
3031  *
3032  * @retval 0		success
3033  * @retval ENXIO	no driver was found
3034  * @retval ENOMEM	memory allocation failure
3035  * @retval non-zero	some other unix error code
3036  */
3037 int
3038 device_detach(device_t dev)
3039 {
3040 	int error;
3041 
3042 	GIANT_REQUIRED;
3043 
3044 	PDEBUG(("%s", DEVICENAME(dev)));
3045 	if (dev->state == DS_BUSY)
3046 		return (EBUSY);
3047 	if (dev->state == DS_ATTACHING) {
3048 		device_printf(dev, "device in attaching state! Deferring detach.\n");
3049 		return (EBUSY);
3050 	}
3051 	if (dev->state != DS_ATTACHED)
3052 		return (0);
3053 
3054 	EVENTHANDLER_DIRECT_INVOKE(device_detach, dev, EVHDEV_DETACH_BEGIN);
3055 	if ((error = DEVICE_DETACH(dev)) != 0) {
3056 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3057 		    EVHDEV_DETACH_FAILED);
3058 		return (error);
3059 	} else {
3060 		EVENTHANDLER_DIRECT_INVOKE(device_detach, dev,
3061 		    EVHDEV_DETACH_COMPLETE);
3062 	}
3063 	devremoved(dev);
3064 	if (!device_is_quiet(dev))
3065 		device_printf(dev, "detached\n");
3066 	if (dev->parent)
3067 		BUS_CHILD_DETACHED(dev->parent, dev);
3068 
3069 	if (!(dev->flags & DF_FIXEDCLASS))
3070 		devclass_delete_device(dev->devclass, dev);
3071 
3072 	device_verbose(dev);
3073 	dev->state = DS_NOTPRESENT;
3074 	(void)device_set_driver(dev, NULL);
3075 	device_sysctl_fini(dev);
3076 
3077 	return (0);
3078 }
3079 
3080 /**
3081  * @brief Tells a driver to quiesce itself.
3082  *
3083  * This function is a wrapper around the DEVICE_QUIESCE() driver
3084  * method. If the call to DEVICE_QUIESCE() succeeds.
3085  *
3086  * @param dev		the device to quiesce
3087  *
3088  * @retval 0		success
3089  * @retval ENXIO	no driver was found
3090  * @retval ENOMEM	memory allocation failure
3091  * @retval non-zero	some other unix error code
3092  */
3093 int
3094 device_quiesce(device_t dev)
3095 {
3096 	PDEBUG(("%s", DEVICENAME(dev)));
3097 	if (dev->state == DS_BUSY)
3098 		return (EBUSY);
3099 	if (dev->state != DS_ATTACHED)
3100 		return (0);
3101 
3102 	return (DEVICE_QUIESCE(dev));
3103 }
3104 
3105 /**
3106  * @brief Notify a device of system shutdown
3107  *
3108  * This function calls the DEVICE_SHUTDOWN() driver method if the
3109  * device currently has an attached driver.
3110  *
3111  * @returns the value returned by DEVICE_SHUTDOWN()
3112  */
3113 int
3114 device_shutdown(device_t dev)
3115 {
3116 	if (dev->state < DS_ATTACHED)
3117 		return (0);
3118 	return (DEVICE_SHUTDOWN(dev));
3119 }
3120 
3121 /**
3122  * @brief Set the unit number of a device
3123  *
3124  * This function can be used to override the unit number used for a
3125  * device (e.g. to wire a device to a pre-configured unit number).
3126  */
3127 int
3128 device_set_unit(device_t dev, int unit)
3129 {
3130 	devclass_t dc;
3131 	int err;
3132 
3133 	dc = device_get_devclass(dev);
3134 	if (unit < dc->maxunit && dc->devices[unit])
3135 		return (EBUSY);
3136 	err = devclass_delete_device(dc, dev);
3137 	if (err)
3138 		return (err);
3139 	dev->unit = unit;
3140 	err = devclass_add_device(dc, dev);
3141 	if (err)
3142 		return (err);
3143 
3144 	bus_data_generation_update();
3145 	return (0);
3146 }
3147 
3148 /*======================================*/
3149 /*
3150  * Some useful method implementations to make life easier for bus drivers.
3151  */
3152 
3153 void
3154 resource_init_map_request_impl(struct resource_map_request *args, size_t sz)
3155 {
3156 	bzero(args, sz);
3157 	args->size = sz;
3158 	args->memattr = VM_MEMATTR_UNCACHEABLE;
3159 }
3160 
3161 /**
3162  * @brief Initialise a resource list.
3163  *
3164  * @param rl		the resource list to initialise
3165  */
3166 void
3167 resource_list_init(struct resource_list *rl)
3168 {
3169 	STAILQ_INIT(rl);
3170 }
3171 
3172 /**
3173  * @brief Reclaim memory used by a resource list.
3174  *
3175  * This function frees the memory for all resource entries on the list
3176  * (if any).
3177  *
3178  * @param rl		the resource list to free
3179  */
3180 void
3181 resource_list_free(struct resource_list *rl)
3182 {
3183 	struct resource_list_entry *rle;
3184 
3185 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3186 		if (rle->res)
3187 			panic("resource_list_free: resource entry is busy");
3188 		STAILQ_REMOVE_HEAD(rl, link);
3189 		free(rle, M_BUS);
3190 	}
3191 }
3192 
3193 /**
3194  * @brief Add a resource entry.
3195  *
3196  * This function adds a resource entry using the given @p type, @p
3197  * start, @p end and @p count values. A rid value is chosen by
3198  * searching sequentially for the first unused rid starting at zero.
3199  *
3200  * @param rl		the resource list to edit
3201  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3202  * @param start		the start address of the resource
3203  * @param end		the end address of the resource
3204  * @param count		XXX end-start+1
3205  */
3206 int
3207 resource_list_add_next(struct resource_list *rl, int type, rman_res_t start,
3208     rman_res_t end, rman_res_t count)
3209 {
3210 	int rid;
3211 
3212 	rid = 0;
3213 	while (resource_list_find(rl, type, rid) != NULL)
3214 		rid++;
3215 	resource_list_add(rl, type, rid, start, end, count);
3216 	return (rid);
3217 }
3218 
3219 /**
3220  * @brief Add or modify a resource entry.
3221  *
3222  * If an existing entry exists with the same type and rid, it will be
3223  * modified using the given values of @p start, @p end and @p
3224  * count. If no entry exists, a new one will be created using the
3225  * given values.  The resource list entry that matches is then returned.
3226  *
3227  * @param rl		the resource list to edit
3228  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3229  * @param rid		the resource identifier
3230  * @param start		the start address of the resource
3231  * @param end		the end address of the resource
3232  * @param count		XXX end-start+1
3233  */
3234 struct resource_list_entry *
3235 resource_list_add(struct resource_list *rl, int type, int rid,
3236     rman_res_t start, rman_res_t end, rman_res_t count)
3237 {
3238 	struct resource_list_entry *rle;
3239 
3240 	rle = resource_list_find(rl, type, rid);
3241 	if (!rle) {
3242 		rle = malloc(sizeof(struct resource_list_entry), M_BUS,
3243 		    M_NOWAIT);
3244 		if (!rle)
3245 			panic("resource_list_add: can't record entry");
3246 		STAILQ_INSERT_TAIL(rl, rle, link);
3247 		rle->type = type;
3248 		rle->rid = rid;
3249 		rle->res = NULL;
3250 		rle->flags = 0;
3251 	}
3252 
3253 	if (rle->res)
3254 		panic("resource_list_add: resource entry is busy");
3255 
3256 	rle->start = start;
3257 	rle->end = end;
3258 	rle->count = count;
3259 	return (rle);
3260 }
3261 
3262 /**
3263  * @brief Determine if a resource entry is busy.
3264  *
3265  * Returns true if a resource entry is busy meaning that it has an
3266  * associated resource that is not an unallocated "reserved" resource.
3267  *
3268  * @param rl		the resource list to search
3269  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3270  * @param rid		the resource identifier
3271  *
3272  * @returns Non-zero if the entry is busy, zero otherwise.
3273  */
3274 int
3275 resource_list_busy(struct resource_list *rl, int type, int rid)
3276 {
3277 	struct resource_list_entry *rle;
3278 
3279 	rle = resource_list_find(rl, type, rid);
3280 	if (rle == NULL || rle->res == NULL)
3281 		return (0);
3282 	if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) == RLE_RESERVED) {
3283 		KASSERT(!(rman_get_flags(rle->res) & RF_ACTIVE),
3284 		    ("reserved resource is active"));
3285 		return (0);
3286 	}
3287 	return (1);
3288 }
3289 
3290 /**
3291  * @brief Determine if a resource entry is reserved.
3292  *
3293  * Returns true if a resource entry is reserved meaning that it has an
3294  * associated "reserved" resource.  The resource can either be
3295  * allocated or unallocated.
3296  *
3297  * @param rl		the resource list to search
3298  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3299  * @param rid		the resource identifier
3300  *
3301  * @returns Non-zero if the entry is reserved, zero otherwise.
3302  */
3303 int
3304 resource_list_reserved(struct resource_list *rl, int type, int rid)
3305 {
3306 	struct resource_list_entry *rle;
3307 
3308 	rle = resource_list_find(rl, type, rid);
3309 	if (rle != NULL && rle->flags & RLE_RESERVED)
3310 		return (1);
3311 	return (0);
3312 }
3313 
3314 /**
3315  * @brief Find a resource entry by type and rid.
3316  *
3317  * @param rl		the resource list to search
3318  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3319  * @param rid		the resource identifier
3320  *
3321  * @returns the resource entry pointer or NULL if there is no such
3322  * entry.
3323  */
3324 struct resource_list_entry *
3325 resource_list_find(struct resource_list *rl, int type, int rid)
3326 {
3327 	struct resource_list_entry *rle;
3328 
3329 	STAILQ_FOREACH(rle, rl, link) {
3330 		if (rle->type == type && rle->rid == rid)
3331 			return (rle);
3332 	}
3333 	return (NULL);
3334 }
3335 
3336 /**
3337  * @brief Delete a resource entry.
3338  *
3339  * @param rl		the resource list to edit
3340  * @param type		the resource entry type (e.g. SYS_RES_MEMORY)
3341  * @param rid		the resource identifier
3342  */
3343 void
3344 resource_list_delete(struct resource_list *rl, int type, int rid)
3345 {
3346 	struct resource_list_entry *rle = resource_list_find(rl, type, rid);
3347 
3348 	if (rle) {
3349 		if (rle->res != NULL)
3350 			panic("resource_list_delete: resource has not been released");
3351 		STAILQ_REMOVE(rl, rle, resource_list_entry, link);
3352 		free(rle, M_BUS);
3353 	}
3354 }
3355 
3356 /**
3357  * @brief Allocate a reserved resource
3358  *
3359  * This can be used by buses to force the allocation of resources
3360  * that are always active in the system even if they are not allocated
3361  * by a driver (e.g. PCI BARs).  This function is usually called when
3362  * adding a new child to the bus.  The resource is allocated from the
3363  * parent bus when it is reserved.  The resource list entry is marked
3364  * with RLE_RESERVED to note that it is a reserved resource.
3365  *
3366  * Subsequent attempts to allocate the resource with
3367  * resource_list_alloc() will succeed the first time and will set
3368  * RLE_ALLOCATED to note that it has been allocated.  When a reserved
3369  * resource that has been allocated is released with
3370  * resource_list_release() the resource RLE_ALLOCATED is cleared, but
3371  * the actual resource remains allocated.  The resource can be released to
3372  * the parent bus by calling resource_list_unreserve().
3373  *
3374  * @param rl		the resource list to allocate from
3375  * @param bus		the parent device of @p child
3376  * @param child		the device for which the resource is being reserved
3377  * @param type		the type of resource to allocate
3378  * @param rid		a pointer to the resource identifier
3379  * @param start		hint at the start of the resource range - pass
3380  *			@c 0 for any start address
3381  * @param end		hint at the end of the resource range - pass
3382  *			@c ~0 for any end address
3383  * @param count		hint at the size of range required - pass @c 1
3384  *			for any size
3385  * @param flags		any extra flags to control the resource
3386  *			allocation - see @c RF_XXX flags in
3387  *			<sys/rman.h> for details
3388  *
3389  * @returns		the resource which was allocated or @c NULL if no
3390  *			resource could be allocated
3391  */
3392 struct resource *
3393 resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
3394     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3395 {
3396 	struct resource_list_entry *rle = NULL;
3397 	int passthrough = (device_get_parent(child) != bus);
3398 	struct resource *r;
3399 
3400 	if (passthrough)
3401 		panic(
3402     "resource_list_reserve() should only be called for direct children");
3403 	if (flags & RF_ACTIVE)
3404 		panic(
3405     "resource_list_reserve() should only reserve inactive resources");
3406 
3407 	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
3408 	    flags);
3409 	if (r != NULL) {
3410 		rle = resource_list_find(rl, type, *rid);
3411 		rle->flags |= RLE_RESERVED;
3412 	}
3413 	return (r);
3414 }
3415 
3416 /**
3417  * @brief Helper function for implementing BUS_ALLOC_RESOURCE()
3418  *
3419  * Implement BUS_ALLOC_RESOURCE() by looking up a resource from the list
3420  * and passing the allocation up to the parent of @p bus. This assumes
3421  * that the first entry of @c device_get_ivars(child) is a struct
3422  * resource_list. This also handles 'passthrough' allocations where a
3423  * child is a remote descendant of bus by passing the allocation up to
3424  * the parent of bus.
3425  *
3426  * Typically, a bus driver would store a list of child resources
3427  * somewhere in the child device's ivars (see device_get_ivars()) and
3428  * its implementation of BUS_ALLOC_RESOURCE() would find that list and
3429  * then call resource_list_alloc() to perform the allocation.
3430  *
3431  * @param rl		the resource list to allocate from
3432  * @param bus		the parent device of @p child
3433  * @param child		the device which is requesting an allocation
3434  * @param type		the type of resource to allocate
3435  * @param rid		a pointer to the resource identifier
3436  * @param start		hint at the start of the resource range - pass
3437  *			@c 0 for any start address
3438  * @param end		hint at the end of the resource range - pass
3439  *			@c ~0 for any end address
3440  * @param count		hint at the size of range required - pass @c 1
3441  *			for any size
3442  * @param flags		any extra flags to control the resource
3443  *			allocation - see @c RF_XXX flags in
3444  *			<sys/rman.h> for details
3445  *
3446  * @returns		the resource which was allocated or @c NULL if no
3447  *			resource could be allocated
3448  */
3449 struct resource *
3450 resource_list_alloc(struct resource_list *rl, device_t bus, device_t child,
3451     int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
3452 {
3453 	struct resource_list_entry *rle = NULL;
3454 	int passthrough = (device_get_parent(child) != bus);
3455 	int isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
3456 
3457 	if (passthrough) {
3458 		return (BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3459 		    type, rid, start, end, count, flags));
3460 	}
3461 
3462 	rle = resource_list_find(rl, type, *rid);
3463 
3464 	if (!rle)
3465 		return (NULL);		/* no resource of that type/rid */
3466 
3467 	if (rle->res) {
3468 		if (rle->flags & RLE_RESERVED) {
3469 			if (rle->flags & RLE_ALLOCATED)
3470 				return (NULL);
3471 			if ((flags & RF_ACTIVE) &&
3472 			    bus_activate_resource(child, type, *rid,
3473 			    rle->res) != 0)
3474 				return (NULL);
3475 			rle->flags |= RLE_ALLOCATED;
3476 			return (rle->res);
3477 		}
3478 		device_printf(bus,
3479 		    "resource entry %#x type %d for child %s is busy\n", *rid,
3480 		    type, device_get_nameunit(child));
3481 		return (NULL);
3482 	}
3483 
3484 	if (isdefault) {
3485 		start = rle->start;
3486 		count = ulmax(count, rle->count);
3487 		end = ulmax(rle->end, start + count - 1);
3488 	}
3489 
3490 	rle->res = BUS_ALLOC_RESOURCE(device_get_parent(bus), child,
3491 	    type, rid, start, end, count, flags);
3492 
3493 	/*
3494 	 * Record the new range.
3495 	 */
3496 	if (rle->res) {
3497 		rle->start = rman_get_start(rle->res);
3498 		rle->end = rman_get_end(rle->res);
3499 		rle->count = count;
3500 	}
3501 
3502 	return (rle->res);
3503 }
3504 
3505 /**
3506  * @brief Helper function for implementing BUS_RELEASE_RESOURCE()
3507  *
3508  * Implement BUS_RELEASE_RESOURCE() using a resource list. Normally
3509  * used with resource_list_alloc().
3510  *
3511  * @param rl		the resource list which was allocated from
3512  * @param bus		the parent device of @p child
3513  * @param child		the device which is requesting a release
3514  * @param type		the type of resource to release
3515  * @param rid		the resource identifier
3516  * @param res		the resource to release
3517  *
3518  * @retval 0		success
3519  * @retval non-zero	a standard unix error code indicating what
3520  *			error condition prevented the operation
3521  */
3522 int
3523 resource_list_release(struct resource_list *rl, device_t bus, device_t child,
3524     int type, int rid, struct resource *res)
3525 {
3526 	struct resource_list_entry *rle = NULL;
3527 	int passthrough = (device_get_parent(child) != bus);
3528 	int error;
3529 
3530 	if (passthrough) {
3531 		return (BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3532 		    type, rid, res));
3533 	}
3534 
3535 	rle = resource_list_find(rl, type, rid);
3536 
3537 	if (!rle)
3538 		panic("resource_list_release: can't find resource");
3539 	if (!rle->res)
3540 		panic("resource_list_release: resource entry is not busy");
3541 	if (rle->flags & RLE_RESERVED) {
3542 		if (rle->flags & RLE_ALLOCATED) {
3543 			if (rman_get_flags(res) & RF_ACTIVE) {
3544 				error = bus_deactivate_resource(child, type,
3545 				    rid, res);
3546 				if (error)
3547 					return (error);
3548 			}
3549 			rle->flags &= ~RLE_ALLOCATED;
3550 			return (0);
3551 		}
3552 		return (EINVAL);
3553 	}
3554 
3555 	error = BUS_RELEASE_RESOURCE(device_get_parent(bus), child,
3556 	    type, rid, res);
3557 	if (error)
3558 		return (error);
3559 
3560 	rle->res = NULL;
3561 	return (0);
3562 }
3563 
3564 /**
3565  * @brief Release all active resources of a given type
3566  *
3567  * Release all active resources of a specified type.  This is intended
3568  * to be used to cleanup resources leaked by a driver after detach or
3569  * a failed attach.
3570  *
3571  * @param rl		the resource list which was allocated from
3572  * @param bus		the parent device of @p child
3573  * @param child		the device whose active resources are being released
3574  * @param type		the type of resources to release
3575  *
3576  * @retval 0		success
3577  * @retval EBUSY	at least one resource was active
3578  */
3579 int
3580 resource_list_release_active(struct resource_list *rl, device_t bus,
3581     device_t child, int type)
3582 {
3583 	struct resource_list_entry *rle;
3584 	int error, retval;
3585 
3586 	retval = 0;
3587 	STAILQ_FOREACH(rle, rl, link) {
3588 		if (rle->type != type)
3589 			continue;
3590 		if (rle->res == NULL)
3591 			continue;
3592 		if ((rle->flags & (RLE_RESERVED | RLE_ALLOCATED)) ==
3593 		    RLE_RESERVED)
3594 			continue;
3595 		retval = EBUSY;
3596 		error = resource_list_release(rl, bus, child, type,
3597 		    rman_get_rid(rle->res), rle->res);
3598 		if (error != 0)
3599 			device_printf(bus,
3600 			    "Failed to release active resource: %d\n", error);
3601 	}
3602 	return (retval);
3603 }
3604 
3605 /**
3606  * @brief Fully release a reserved resource
3607  *
3608  * Fully releases a resource reserved via resource_list_reserve().
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 reserved resource is being released
3613  * @param type		the type of resource to release
3614  * @param rid		the resource identifier
3615  * @param res		the resource to release
3616  *
3617  * @retval 0		success
3618  * @retval non-zero	a standard unix error code indicating what
3619  *			error condition prevented the operation
3620  */
3621 int
3622 resource_list_unreserve(struct resource_list *rl, device_t bus, device_t child,
3623     int type, int rid)
3624 {
3625 	struct resource_list_entry *rle = NULL;
3626 	int passthrough = (device_get_parent(child) != bus);
3627 
3628 	if (passthrough)
3629 		panic(
3630     "resource_list_unreserve() should only be called for direct children");
3631 
3632 	rle = resource_list_find(rl, type, rid);
3633 
3634 	if (!rle)
3635 		panic("resource_list_unreserve: can't find resource");
3636 	if (!(rle->flags & RLE_RESERVED))
3637 		return (EINVAL);
3638 	if (rle->flags & RLE_ALLOCATED)
3639 		return (EBUSY);
3640 	rle->flags &= ~RLE_RESERVED;
3641 	return (resource_list_release(rl, bus, child, type, rid, rle->res));
3642 }
3643 
3644 /**
3645  * @brief Print a description of resources in a resource list
3646  *
3647  * Print all resources of a specified type, for use in BUS_PRINT_CHILD().
3648  * The name is printed if at least one resource of the given type is available.
3649  * The format is used to print resource start and end.
3650  *
3651  * @param rl		the resource list to print
3652  * @param name		the name of @p type, e.g. @c "memory"
3653  * @param type		type type of resource entry to print
3654  * @param format	printf(9) format string to print resource
3655  *			start and end values
3656  *
3657  * @returns		the number of characters printed
3658  */
3659 int
3660 resource_list_print_type(struct resource_list *rl, const char *name, int type,
3661     const char *format)
3662 {
3663 	struct resource_list_entry *rle;
3664 	int printed, retval;
3665 
3666 	printed = 0;
3667 	retval = 0;
3668 	/* Yes, this is kinda cheating */
3669 	STAILQ_FOREACH(rle, rl, link) {
3670 		if (rle->type == type) {
3671 			if (printed == 0)
3672 				retval += printf(" %s ", name);
3673 			else
3674 				retval += printf(",");
3675 			printed++;
3676 			retval += printf(format, rle->start);
3677 			if (rle->count > 1) {
3678 				retval += printf("-");
3679 				retval += printf(format, rle->start +
3680 						 rle->count - 1);
3681 			}
3682 		}
3683 	}
3684 	return (retval);
3685 }
3686 
3687 /**
3688  * @brief Releases all the resources in a list.
3689  *
3690  * @param rl		The resource list to purge.
3691  *
3692  * @returns		nothing
3693  */
3694 void
3695 resource_list_purge(struct resource_list *rl)
3696 {
3697 	struct resource_list_entry *rle;
3698 
3699 	while ((rle = STAILQ_FIRST(rl)) != NULL) {
3700 		if (rle->res)
3701 			bus_release_resource(rman_get_device(rle->res),
3702 			    rle->type, rle->rid, rle->res);
3703 		STAILQ_REMOVE_HEAD(rl, link);
3704 		free(rle, M_BUS);
3705 	}
3706 }
3707 
3708 device_t
3709 bus_generic_add_child(device_t dev, u_int order, const char *name, int unit)
3710 {
3711 	return (device_add_child_ordered(dev, order, name, unit));
3712 }
3713 
3714 /**
3715  * @brief Helper function for implementing DEVICE_PROBE()
3716  *
3717  * This function can be used to help implement the DEVICE_PROBE() for
3718  * a bus (i.e. a device which has other devices attached to it). It
3719  * calls the DEVICE_IDENTIFY() method of each driver in the device's
3720  * devclass.
3721  */
3722 int
3723 bus_generic_probe(device_t dev)
3724 {
3725 	devclass_t dc = dev->devclass;
3726 	driverlink_t dl;
3727 
3728 	TAILQ_FOREACH(dl, &dc->drivers, link) {
3729 		/*
3730 		 * If this driver's pass is too high, then ignore it.
3731 		 * For most drivers in the default pass, this will
3732 		 * never be true.  For early-pass drivers they will
3733 		 * only call the identify routines of eligible drivers
3734 		 * when this routine is called.  Drivers for later
3735 		 * passes should have their identify routines called
3736 		 * on early-pass buses during BUS_NEW_PASS().
3737 		 */
3738 		if (dl->pass > bus_current_pass)
3739 			continue;
3740 		DEVICE_IDENTIFY(dl->driver, dev);
3741 	}
3742 
3743 	return (0);
3744 }
3745 
3746 /**
3747  * @brief Helper function for implementing DEVICE_ATTACH()
3748  *
3749  * This function can be used to help implement the DEVICE_ATTACH() for
3750  * a bus. It calls device_probe_and_attach() for each of the device's
3751  * children.
3752  */
3753 int
3754 bus_generic_attach(device_t dev)
3755 {
3756 	device_t child;
3757 
3758 	TAILQ_FOREACH(child, &dev->children, link) {
3759 		device_probe_and_attach(child);
3760 	}
3761 
3762 	return (0);
3763 }
3764 
3765 /**
3766  * @brief Helper function for delaying attaching children
3767  *
3768  * Many buses can't run transactions on the bus which children need to probe and
3769  * attach until after interrupts and/or timers are running.  This function
3770  * delays their attach until interrupts and timers are enabled.
3771  */
3772 int
3773 bus_delayed_attach_children(device_t dev)
3774 {
3775 	/* Probe and attach the bus children when interrupts are available */
3776 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
3777 
3778 	return (0);
3779 }
3780 
3781 /**
3782  * @brief Helper function for implementing DEVICE_DETACH()
3783  *
3784  * This function can be used to help implement the DEVICE_DETACH() for
3785  * a bus. It calls device_detach() for each of the device's
3786  * children.
3787  */
3788 int
3789 bus_generic_detach(device_t dev)
3790 {
3791 	device_t child;
3792 	int error;
3793 
3794 	if (dev->state != DS_ATTACHED)
3795 		return (EBUSY);
3796 
3797 	/*
3798 	 * Detach children in the reverse order.
3799 	 * See bus_generic_suspend for details.
3800 	 */
3801 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3802 		if ((error = device_detach(child)) != 0)
3803 			return (error);
3804 	}
3805 
3806 	return (0);
3807 }
3808 
3809 /**
3810  * @brief Helper function for implementing DEVICE_SHUTDOWN()
3811  *
3812  * This function can be used to help implement the DEVICE_SHUTDOWN()
3813  * for a bus. It calls device_shutdown() for each of the device's
3814  * children.
3815  */
3816 int
3817 bus_generic_shutdown(device_t dev)
3818 {
3819 	device_t child;
3820 
3821 	/*
3822 	 * Shut down children in the reverse order.
3823 	 * See bus_generic_suspend for details.
3824 	 */
3825 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3826 		device_shutdown(child);
3827 	}
3828 
3829 	return (0);
3830 }
3831 
3832 /**
3833  * @brief Default function for suspending a child device.
3834  *
3835  * This function is to be used by a bus's DEVICE_SUSPEND_CHILD().
3836  */
3837 int
3838 bus_generic_suspend_child(device_t dev, device_t child)
3839 {
3840 	int	error;
3841 
3842 	error = DEVICE_SUSPEND(child);
3843 
3844 	if (error == 0)
3845 		child->flags |= DF_SUSPENDED;
3846 
3847 	return (error);
3848 }
3849 
3850 /**
3851  * @brief Default function for resuming a child device.
3852  *
3853  * This function is to be used by a bus's DEVICE_RESUME_CHILD().
3854  */
3855 int
3856 bus_generic_resume_child(device_t dev, device_t child)
3857 {
3858 	DEVICE_RESUME(child);
3859 	child->flags &= ~DF_SUSPENDED;
3860 
3861 	return (0);
3862 }
3863 
3864 /**
3865  * @brief Helper function for implementing DEVICE_SUSPEND()
3866  *
3867  * This function can be used to help implement the DEVICE_SUSPEND()
3868  * for a bus. It calls DEVICE_SUSPEND() for each of the device's
3869  * children. If any call to DEVICE_SUSPEND() fails, the suspend
3870  * operation is aborted and any devices which were suspended are
3871  * resumed immediately by calling their DEVICE_RESUME() methods.
3872  */
3873 int
3874 bus_generic_suspend(device_t dev)
3875 {
3876 	int		error;
3877 	device_t	child;
3878 
3879 	/*
3880 	 * Suspend children in the reverse order.
3881 	 * For most buses all children are equal, so the order does not matter.
3882 	 * Other buses, such as acpi, carefully order their child devices to
3883 	 * express implicit dependencies between them.  For such buses it is
3884 	 * safer to bring down devices in the reverse order.
3885 	 */
3886 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3887 		error = BUS_SUSPEND_CHILD(dev, child);
3888 		if (error != 0) {
3889 			child = TAILQ_NEXT(child, link);
3890 			if (child != NULL) {
3891 				TAILQ_FOREACH_FROM(child, &dev->children, link)
3892 					BUS_RESUME_CHILD(dev, child);
3893 			}
3894 			return (error);
3895 		}
3896 	}
3897 	return (0);
3898 }
3899 
3900 /**
3901  * @brief Helper function for implementing DEVICE_RESUME()
3902  *
3903  * This function can be used to help implement the DEVICE_RESUME() for
3904  * a bus. It calls DEVICE_RESUME() on each of the device's children.
3905  */
3906 int
3907 bus_generic_resume(device_t dev)
3908 {
3909 	device_t	child;
3910 
3911 	TAILQ_FOREACH(child, &dev->children, link) {
3912 		BUS_RESUME_CHILD(dev, child);
3913 		/* if resume fails, there's nothing we can usefully do... */
3914 	}
3915 	return (0);
3916 }
3917 
3918 /**
3919  * @brief Helper function for implementing BUS_RESET_POST
3920  *
3921  * Bus can use this function to implement common operations of
3922  * re-attaching or resuming the children after the bus itself was
3923  * reset, and after restoring bus-unique state of children.
3924  *
3925  * @param dev	The bus
3926  * #param flags	DEVF_RESET_*
3927  */
3928 int
3929 bus_helper_reset_post(device_t dev, int flags)
3930 {
3931 	device_t child;
3932 	int error, error1;
3933 
3934 	error = 0;
3935 	TAILQ_FOREACH(child, &dev->children,link) {
3936 		BUS_RESET_POST(dev, child);
3937 		error1 = (flags & DEVF_RESET_DETACH) != 0 ?
3938 		    device_probe_and_attach(child) :
3939 		    BUS_RESUME_CHILD(dev, child);
3940 		if (error == 0 && error1 != 0)
3941 			error = error1;
3942 	}
3943 	return (error);
3944 }
3945 
3946 static void
3947 bus_helper_reset_prepare_rollback(device_t dev, device_t child, int flags)
3948 {
3949 	child = TAILQ_NEXT(child, link);
3950 	if (child == NULL)
3951 		return;
3952 	TAILQ_FOREACH_FROM(child, &dev->children,link) {
3953 		BUS_RESET_POST(dev, child);
3954 		if ((flags & DEVF_RESET_DETACH) != 0)
3955 			device_probe_and_attach(child);
3956 		else
3957 			BUS_RESUME_CHILD(dev, child);
3958 	}
3959 }
3960 
3961 /**
3962  * @brief Helper function for implementing BUS_RESET_PREPARE
3963  *
3964  * Bus can use this function to implement common operations of
3965  * detaching or suspending the children before the bus itself is
3966  * reset, and then save bus-unique state of children that must
3967  * persists around reset.
3968  *
3969  * @param dev	The bus
3970  * #param flags	DEVF_RESET_*
3971  */
3972 int
3973 bus_helper_reset_prepare(device_t dev, int flags)
3974 {
3975 	device_t child;
3976 	int error;
3977 
3978 	if (dev->state != DS_ATTACHED)
3979 		return (EBUSY);
3980 
3981 	TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, link) {
3982 		if ((flags & DEVF_RESET_DETACH) != 0) {
3983 			error = device_get_state(child) == DS_ATTACHED ?
3984 			    device_detach(child) : 0;
3985 		} else {
3986 			error = BUS_SUSPEND_CHILD(dev, child);
3987 		}
3988 		if (error == 0) {
3989 			error = BUS_RESET_PREPARE(dev, child);
3990 			if (error != 0) {
3991 				if ((flags & DEVF_RESET_DETACH) != 0)
3992 					device_probe_and_attach(child);
3993 				else
3994 					BUS_RESUME_CHILD(dev, child);
3995 			}
3996 		}
3997 		if (error != 0) {
3998 			bus_helper_reset_prepare_rollback(dev, child, flags);
3999 			return (error);
4000 		}
4001 	}
4002 	return (0);
4003 }
4004 
4005 /**
4006  * @brief Helper function for implementing BUS_PRINT_CHILD().
4007  *
4008  * This function prints the first part of the ascii representation of
4009  * @p child, including its name, unit and description (if any - see
4010  * device_set_desc()).
4011  *
4012  * @returns the number of characters printed
4013  */
4014 int
4015 bus_print_child_header(device_t dev, device_t child)
4016 {
4017 	int	retval = 0;
4018 
4019 	if (device_get_desc(child)) {
4020 		retval += device_printf(child, "<%s>", device_get_desc(child));
4021 	} else {
4022 		retval += printf("%s", device_get_nameunit(child));
4023 	}
4024 
4025 	return (retval);
4026 }
4027 
4028 /**
4029  * @brief Helper function for implementing BUS_PRINT_CHILD().
4030  *
4031  * This function prints the last part of the ascii representation of
4032  * @p child, which consists of the string @c " on " followed by the
4033  * name and unit of the @p dev.
4034  *
4035  * @returns the number of characters printed
4036  */
4037 int
4038 bus_print_child_footer(device_t dev, device_t child)
4039 {
4040 	return (printf(" on %s\n", device_get_nameunit(dev)));
4041 }
4042 
4043 /**
4044  * @brief Helper function for implementing BUS_PRINT_CHILD().
4045  *
4046  * This function prints out the VM domain for the given device.
4047  *
4048  * @returns the number of characters printed
4049  */
4050 int
4051 bus_print_child_domain(device_t dev, device_t child)
4052 {
4053 	int domain;
4054 
4055 	/* No domain? Don't print anything */
4056 	if (BUS_GET_DOMAIN(dev, child, &domain) != 0)
4057 		return (0);
4058 
4059 	return (printf(" numa-domain %d", domain));
4060 }
4061 
4062 /**
4063  * @brief Helper function for implementing BUS_PRINT_CHILD().
4064  *
4065  * This function simply calls bus_print_child_header() followed by
4066  * bus_print_child_footer().
4067  *
4068  * @returns the number of characters printed
4069  */
4070 int
4071 bus_generic_print_child(device_t dev, device_t child)
4072 {
4073 	int	retval = 0;
4074 
4075 	retval += bus_print_child_header(dev, child);
4076 	retval += bus_print_child_domain(dev, child);
4077 	retval += bus_print_child_footer(dev, child);
4078 
4079 	return (retval);
4080 }
4081 
4082 /**
4083  * @brief Stub function for implementing BUS_READ_IVAR().
4084  *
4085  * @returns ENOENT
4086  */
4087 int
4088 bus_generic_read_ivar(device_t dev, device_t child, int index,
4089     uintptr_t * result)
4090 {
4091 	return (ENOENT);
4092 }
4093 
4094 /**
4095  * @brief Stub function for implementing BUS_WRITE_IVAR().
4096  *
4097  * @returns ENOENT
4098  */
4099 int
4100 bus_generic_write_ivar(device_t dev, device_t child, int index,
4101     uintptr_t value)
4102 {
4103 	return (ENOENT);
4104 }
4105 
4106 /**
4107  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
4108  *
4109  * @returns NULL
4110  */
4111 struct resource_list *
4112 bus_generic_get_resource_list(device_t dev, device_t child)
4113 {
4114 	return (NULL);
4115 }
4116 
4117 /**
4118  * @brief Helper function for implementing BUS_DRIVER_ADDED().
4119  *
4120  * This implementation of BUS_DRIVER_ADDED() simply calls the driver's
4121  * DEVICE_IDENTIFY() method to allow it to add new children to the bus
4122  * and then calls device_probe_and_attach() for each unattached child.
4123  */
4124 void
4125 bus_generic_driver_added(device_t dev, driver_t *driver)
4126 {
4127 	device_t child;
4128 
4129 	DEVICE_IDENTIFY(driver, dev);
4130 	TAILQ_FOREACH(child, &dev->children, link) {
4131 		if (child->state == DS_NOTPRESENT ||
4132 		    (child->flags & DF_REBID))
4133 			device_probe_and_attach(child);
4134 	}
4135 }
4136 
4137 /**
4138  * @brief Helper function for implementing BUS_NEW_PASS().
4139  *
4140  * This implementing of BUS_NEW_PASS() first calls the identify
4141  * routines for any drivers that probe at the current pass.  Then it
4142  * walks the list of devices for this bus.  If a device is already
4143  * attached, then it calls BUS_NEW_PASS() on that device.  If the
4144  * device is not already attached, it attempts to attach a driver to
4145  * it.
4146  */
4147 void
4148 bus_generic_new_pass(device_t dev)
4149 {
4150 	driverlink_t dl;
4151 	devclass_t dc;
4152 	device_t child;
4153 
4154 	dc = dev->devclass;
4155 	TAILQ_FOREACH(dl, &dc->drivers, link) {
4156 		if (dl->pass == bus_current_pass)
4157 			DEVICE_IDENTIFY(dl->driver, dev);
4158 	}
4159 	TAILQ_FOREACH(child, &dev->children, link) {
4160 		if (child->state >= DS_ATTACHED)
4161 			BUS_NEW_PASS(child);
4162 		else if (child->state == DS_NOTPRESENT)
4163 			device_probe_and_attach(child);
4164 	}
4165 }
4166 
4167 /**
4168  * @brief Helper function for implementing BUS_SETUP_INTR().
4169  *
4170  * This simple implementation of BUS_SETUP_INTR() simply calls the
4171  * BUS_SETUP_INTR() method of the parent of @p dev.
4172  */
4173 int
4174 bus_generic_setup_intr(device_t dev, device_t child, struct resource *irq,
4175     int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
4176     void **cookiep)
4177 {
4178 	/* Propagate up the bus hierarchy until someone handles it. */
4179 	if (dev->parent)
4180 		return (BUS_SETUP_INTR(dev->parent, child, irq, flags,
4181 		    filter, intr, arg, cookiep));
4182 	return (EINVAL);
4183 }
4184 
4185 /**
4186  * @brief Helper function for implementing BUS_TEARDOWN_INTR().
4187  *
4188  * This simple implementation of BUS_TEARDOWN_INTR() simply calls the
4189  * BUS_TEARDOWN_INTR() method of the parent of @p dev.
4190  */
4191 int
4192 bus_generic_teardown_intr(device_t dev, device_t child, struct resource *irq,
4193     void *cookie)
4194 {
4195 	/* Propagate up the bus hierarchy until someone handles it. */
4196 	if (dev->parent)
4197 		return (BUS_TEARDOWN_INTR(dev->parent, child, irq, cookie));
4198 	return (EINVAL);
4199 }
4200 
4201 /**
4202  * @brief Helper function for implementing BUS_SUSPEND_INTR().
4203  *
4204  * This simple implementation of BUS_SUSPEND_INTR() simply calls the
4205  * BUS_SUSPEND_INTR() method of the parent of @p dev.
4206  */
4207 int
4208 bus_generic_suspend_intr(device_t dev, device_t child, struct resource *irq)
4209 {
4210 	/* Propagate up the bus hierarchy until someone handles it. */
4211 	if (dev->parent)
4212 		return (BUS_SUSPEND_INTR(dev->parent, child, irq));
4213 	return (EINVAL);
4214 }
4215 
4216 /**
4217  * @brief Helper function for implementing BUS_RESUME_INTR().
4218  *
4219  * This simple implementation of BUS_RESUME_INTR() simply calls the
4220  * BUS_RESUME_INTR() method of the parent of @p dev.
4221  */
4222 int
4223 bus_generic_resume_intr(device_t dev, device_t child, struct resource *irq)
4224 {
4225 	/* Propagate up the bus hierarchy until someone handles it. */
4226 	if (dev->parent)
4227 		return (BUS_RESUME_INTR(dev->parent, child, irq));
4228 	return (EINVAL);
4229 }
4230 
4231 /**
4232  * @brief Helper function for implementing BUS_ADJUST_RESOURCE().
4233  *
4234  * This simple implementation of BUS_ADJUST_RESOURCE() simply calls the
4235  * BUS_ADJUST_RESOURCE() method of the parent of @p dev.
4236  */
4237 int
4238 bus_generic_adjust_resource(device_t dev, device_t child, int type,
4239     struct resource *r, rman_res_t start, rman_res_t end)
4240 {
4241 	/* Propagate up the bus hierarchy until someone handles it. */
4242 	if (dev->parent)
4243 		return (BUS_ADJUST_RESOURCE(dev->parent, child, type, r, start,
4244 		    end));
4245 	return (EINVAL);
4246 }
4247 
4248 /**
4249  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4250  *
4251  * This simple implementation of BUS_ALLOC_RESOURCE() simply calls the
4252  * BUS_ALLOC_RESOURCE() method of the parent of @p dev.
4253  */
4254 struct resource *
4255 bus_generic_alloc_resource(device_t dev, device_t child, int type, int *rid,
4256     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4257 {
4258 	/* Propagate up the bus hierarchy until someone handles it. */
4259 	if (dev->parent)
4260 		return (BUS_ALLOC_RESOURCE(dev->parent, child, type, rid,
4261 		    start, end, count, flags));
4262 	return (NULL);
4263 }
4264 
4265 /**
4266  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4267  *
4268  * This simple implementation of BUS_RELEASE_RESOURCE() simply calls the
4269  * BUS_RELEASE_RESOURCE() method of the parent of @p dev.
4270  */
4271 int
4272 bus_generic_release_resource(device_t dev, device_t child, int type, int rid,
4273     struct resource *r)
4274 {
4275 	/* Propagate up the bus hierarchy until someone handles it. */
4276 	if (dev->parent)
4277 		return (BUS_RELEASE_RESOURCE(dev->parent, child, type, rid,
4278 		    r));
4279 	return (EINVAL);
4280 }
4281 
4282 /**
4283  * @brief Helper function for implementing BUS_ACTIVATE_RESOURCE().
4284  *
4285  * This simple implementation of BUS_ACTIVATE_RESOURCE() simply calls the
4286  * BUS_ACTIVATE_RESOURCE() method of the parent of @p dev.
4287  */
4288 int
4289 bus_generic_activate_resource(device_t dev, device_t child, int type, int rid,
4290     struct resource *r)
4291 {
4292 	/* Propagate up the bus hierarchy until someone handles it. */
4293 	if (dev->parent)
4294 		return (BUS_ACTIVATE_RESOURCE(dev->parent, child, type, rid,
4295 		    r));
4296 	return (EINVAL);
4297 }
4298 
4299 /**
4300  * @brief Helper function for implementing BUS_DEACTIVATE_RESOURCE().
4301  *
4302  * This simple implementation of BUS_DEACTIVATE_RESOURCE() simply calls the
4303  * BUS_DEACTIVATE_RESOURCE() method of the parent of @p dev.
4304  */
4305 int
4306 bus_generic_deactivate_resource(device_t dev, device_t child, int type,
4307     int rid, struct resource *r)
4308 {
4309 	/* Propagate up the bus hierarchy until someone handles it. */
4310 	if (dev->parent)
4311 		return (BUS_DEACTIVATE_RESOURCE(dev->parent, child, type, rid,
4312 		    r));
4313 	return (EINVAL);
4314 }
4315 
4316 /**
4317  * @brief Helper function for implementing BUS_MAP_RESOURCE().
4318  *
4319  * This simple implementation of BUS_MAP_RESOURCE() simply calls the
4320  * BUS_MAP_RESOURCE() method of the parent of @p dev.
4321  */
4322 int
4323 bus_generic_map_resource(device_t dev, device_t child, int type,
4324     struct resource *r, struct resource_map_request *args,
4325     struct resource_map *map)
4326 {
4327 	/* Propagate up the bus hierarchy until someone handles it. */
4328 	if (dev->parent)
4329 		return (BUS_MAP_RESOURCE(dev->parent, child, type, r, args,
4330 		    map));
4331 	return (EINVAL);
4332 }
4333 
4334 /**
4335  * @brief Helper function for implementing BUS_UNMAP_RESOURCE().
4336  *
4337  * This simple implementation of BUS_UNMAP_RESOURCE() simply calls the
4338  * BUS_UNMAP_RESOURCE() method of the parent of @p dev.
4339  */
4340 int
4341 bus_generic_unmap_resource(device_t dev, device_t child, int type,
4342     struct resource *r, struct resource_map *map)
4343 {
4344 	/* Propagate up the bus hierarchy until someone handles it. */
4345 	if (dev->parent)
4346 		return (BUS_UNMAP_RESOURCE(dev->parent, child, type, r, map));
4347 	return (EINVAL);
4348 }
4349 
4350 /**
4351  * @brief Helper function for implementing BUS_BIND_INTR().
4352  *
4353  * This simple implementation of BUS_BIND_INTR() simply calls the
4354  * BUS_BIND_INTR() method of the parent of @p dev.
4355  */
4356 int
4357 bus_generic_bind_intr(device_t dev, device_t child, struct resource *irq,
4358     int cpu)
4359 {
4360 	/* Propagate up the bus hierarchy until someone handles it. */
4361 	if (dev->parent)
4362 		return (BUS_BIND_INTR(dev->parent, child, irq, cpu));
4363 	return (EINVAL);
4364 }
4365 
4366 /**
4367  * @brief Helper function for implementing BUS_CONFIG_INTR().
4368  *
4369  * This simple implementation of BUS_CONFIG_INTR() simply calls the
4370  * BUS_CONFIG_INTR() method of the parent of @p dev.
4371  */
4372 int
4373 bus_generic_config_intr(device_t dev, int irq, enum intr_trigger trig,
4374     enum intr_polarity pol)
4375 {
4376 	/* Propagate up the bus hierarchy until someone handles it. */
4377 	if (dev->parent)
4378 		return (BUS_CONFIG_INTR(dev->parent, irq, trig, pol));
4379 	return (EINVAL);
4380 }
4381 
4382 /**
4383  * @brief Helper function for implementing BUS_DESCRIBE_INTR().
4384  *
4385  * This simple implementation of BUS_DESCRIBE_INTR() simply calls the
4386  * BUS_DESCRIBE_INTR() method of the parent of @p dev.
4387  */
4388 int
4389 bus_generic_describe_intr(device_t dev, device_t child, struct resource *irq,
4390     void *cookie, const char *descr)
4391 {
4392 	/* Propagate up the bus hierarchy until someone handles it. */
4393 	if (dev->parent)
4394 		return (BUS_DESCRIBE_INTR(dev->parent, child, irq, cookie,
4395 		    descr));
4396 	return (EINVAL);
4397 }
4398 
4399 /**
4400  * @brief Helper function for implementing BUS_GET_CPUS().
4401  *
4402  * This simple implementation of BUS_GET_CPUS() simply calls the
4403  * BUS_GET_CPUS() method of the parent of @p dev.
4404  */
4405 int
4406 bus_generic_get_cpus(device_t dev, device_t child, enum cpu_sets op,
4407     size_t setsize, cpuset_t *cpuset)
4408 {
4409 	/* Propagate up the bus hierarchy until someone handles it. */
4410 	if (dev->parent != NULL)
4411 		return (BUS_GET_CPUS(dev->parent, child, op, setsize, cpuset));
4412 	return (EINVAL);
4413 }
4414 
4415 /**
4416  * @brief Helper function for implementing BUS_GET_DMA_TAG().
4417  *
4418  * This simple implementation of BUS_GET_DMA_TAG() simply calls the
4419  * BUS_GET_DMA_TAG() method of the parent of @p dev.
4420  */
4421 bus_dma_tag_t
4422 bus_generic_get_dma_tag(device_t dev, device_t child)
4423 {
4424 	/* Propagate up the bus hierarchy until someone handles it. */
4425 	if (dev->parent != NULL)
4426 		return (BUS_GET_DMA_TAG(dev->parent, child));
4427 	return (NULL);
4428 }
4429 
4430 /**
4431  * @brief Helper function for implementing BUS_GET_BUS_TAG().
4432  *
4433  * This simple implementation of BUS_GET_BUS_TAG() simply calls the
4434  * BUS_GET_BUS_TAG() method of the parent of @p dev.
4435  */
4436 bus_space_tag_t
4437 bus_generic_get_bus_tag(device_t dev, device_t child)
4438 {
4439 	/* Propagate up the bus hierarchy until someone handles it. */
4440 	if (dev->parent != NULL)
4441 		return (BUS_GET_BUS_TAG(dev->parent, child));
4442 	return ((bus_space_tag_t)0);
4443 }
4444 
4445 /**
4446  * @brief Helper function for implementing BUS_GET_RESOURCE().
4447  *
4448  * This implementation of BUS_GET_RESOURCE() uses the
4449  * resource_list_find() function to do most of the work. It calls
4450  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4451  * search.
4452  */
4453 int
4454 bus_generic_rl_get_resource(device_t dev, device_t child, int type, int rid,
4455     rman_res_t *startp, rman_res_t *countp)
4456 {
4457 	struct resource_list *		rl = NULL;
4458 	struct resource_list_entry *	rle = NULL;
4459 
4460 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4461 	if (!rl)
4462 		return (EINVAL);
4463 
4464 	rle = resource_list_find(rl, type, rid);
4465 	if (!rle)
4466 		return (ENOENT);
4467 
4468 	if (startp)
4469 		*startp = rle->start;
4470 	if (countp)
4471 		*countp = rle->count;
4472 
4473 	return (0);
4474 }
4475 
4476 /**
4477  * @brief Helper function for implementing BUS_SET_RESOURCE().
4478  *
4479  * This implementation of BUS_SET_RESOURCE() uses the
4480  * resource_list_add() function to do most of the work. It calls
4481  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4482  * edit.
4483  */
4484 int
4485 bus_generic_rl_set_resource(device_t dev, device_t child, int type, int rid,
4486     rman_res_t start, rman_res_t count)
4487 {
4488 	struct resource_list *		rl = NULL;
4489 
4490 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4491 	if (!rl)
4492 		return (EINVAL);
4493 
4494 	resource_list_add(rl, type, rid, start, (start + count - 1), count);
4495 
4496 	return (0);
4497 }
4498 
4499 /**
4500  * @brief Helper function for implementing BUS_DELETE_RESOURCE().
4501  *
4502  * This implementation of BUS_DELETE_RESOURCE() uses the
4503  * resource_list_delete() function to do most of the work. It calls
4504  * BUS_GET_RESOURCE_LIST() to find a suitable resource list to
4505  * edit.
4506  */
4507 void
4508 bus_generic_rl_delete_resource(device_t dev, device_t child, int type, int rid)
4509 {
4510 	struct resource_list *		rl = NULL;
4511 
4512 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4513 	if (!rl)
4514 		return;
4515 
4516 	resource_list_delete(rl, type, rid);
4517 
4518 	return;
4519 }
4520 
4521 /**
4522  * @brief Helper function for implementing BUS_RELEASE_RESOURCE().
4523  *
4524  * This implementation of BUS_RELEASE_RESOURCE() uses the
4525  * resource_list_release() function to do most of the work. It calls
4526  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4527  */
4528 int
4529 bus_generic_rl_release_resource(device_t dev, device_t child, int type,
4530     int rid, struct resource *r)
4531 {
4532 	struct resource_list *		rl = NULL;
4533 
4534 	if (device_get_parent(child) != dev)
4535 		return (BUS_RELEASE_RESOURCE(device_get_parent(dev), child,
4536 		    type, rid, r));
4537 
4538 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4539 	if (!rl)
4540 		return (EINVAL);
4541 
4542 	return (resource_list_release(rl, dev, child, type, rid, r));
4543 }
4544 
4545 /**
4546  * @brief Helper function for implementing BUS_ALLOC_RESOURCE().
4547  *
4548  * This implementation of BUS_ALLOC_RESOURCE() uses the
4549  * resource_list_alloc() function to do most of the work. It calls
4550  * BUS_GET_RESOURCE_LIST() to find a suitable resource list.
4551  */
4552 struct resource *
4553 bus_generic_rl_alloc_resource(device_t dev, device_t child, int type,
4554     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
4555 {
4556 	struct resource_list *		rl = NULL;
4557 
4558 	if (device_get_parent(child) != dev)
4559 		return (BUS_ALLOC_RESOURCE(device_get_parent(dev), child,
4560 		    type, rid, start, end, count, flags));
4561 
4562 	rl = BUS_GET_RESOURCE_LIST(dev, child);
4563 	if (!rl)
4564 		return (NULL);
4565 
4566 	return (resource_list_alloc(rl, dev, child, type, rid,
4567 	    start, end, count, flags));
4568 }
4569 
4570 /**
4571  * @brief Helper function for implementing BUS_CHILD_PRESENT().
4572  *
4573  * This simple implementation of BUS_CHILD_PRESENT() simply calls the
4574  * BUS_CHILD_PRESENT() method of the parent of @p dev.
4575  */
4576 int
4577 bus_generic_child_present(device_t dev, device_t child)
4578 {
4579 	return (BUS_CHILD_PRESENT(device_get_parent(dev), dev));
4580 }
4581 
4582 int
4583 bus_generic_get_domain(device_t dev, device_t child, int *domain)
4584 {
4585 	if (dev->parent)
4586 		return (BUS_GET_DOMAIN(dev->parent, dev, domain));
4587 
4588 	return (ENOENT);
4589 }
4590 
4591 /**
4592  * @brief Helper function for implementing BUS_RESCAN().
4593  *
4594  * This null implementation of BUS_RESCAN() always fails to indicate
4595  * the bus does not support rescanning.
4596  */
4597 int
4598 bus_null_rescan(device_t dev)
4599 {
4600 	return (ENXIO);
4601 }
4602 
4603 /*
4604  * Some convenience functions to make it easier for drivers to use the
4605  * resource-management functions.  All these really do is hide the
4606  * indirection through the parent's method table, making for slightly
4607  * less-wordy code.  In the future, it might make sense for this code
4608  * to maintain some sort of a list of resources allocated by each device.
4609  */
4610 
4611 int
4612 bus_alloc_resources(device_t dev, struct resource_spec *rs,
4613     struct resource **res)
4614 {
4615 	int i;
4616 
4617 	for (i = 0; rs[i].type != -1; i++)
4618 		res[i] = NULL;
4619 	for (i = 0; rs[i].type != -1; i++) {
4620 		res[i] = bus_alloc_resource_any(dev,
4621 		    rs[i].type, &rs[i].rid, rs[i].flags);
4622 		if (res[i] == NULL && !(rs[i].flags & RF_OPTIONAL)) {
4623 			bus_release_resources(dev, rs, res);
4624 			return (ENXIO);
4625 		}
4626 	}
4627 	return (0);
4628 }
4629 
4630 void
4631 bus_release_resources(device_t dev, const struct resource_spec *rs,
4632     struct resource **res)
4633 {
4634 	int i;
4635 
4636 	for (i = 0; rs[i].type != -1; i++)
4637 		if (res[i] != NULL) {
4638 			bus_release_resource(
4639 			    dev, rs[i].type, rs[i].rid, res[i]);
4640 			res[i] = NULL;
4641 		}
4642 }
4643 
4644 /**
4645  * @brief Wrapper function for BUS_ALLOC_RESOURCE().
4646  *
4647  * This function simply calls the BUS_ALLOC_RESOURCE() method of the
4648  * parent of @p dev.
4649  */
4650 struct resource *
4651 bus_alloc_resource(device_t dev, int type, int *rid, rman_res_t start,
4652     rman_res_t end, rman_res_t count, u_int flags)
4653 {
4654 	struct resource *res;
4655 
4656 	if (dev->parent == NULL)
4657 		return (NULL);
4658 	res = BUS_ALLOC_RESOURCE(dev->parent, dev, type, rid, start, end,
4659 	    count, flags);
4660 	return (res);
4661 }
4662 
4663 /**
4664  * @brief Wrapper function for BUS_ADJUST_RESOURCE().
4665  *
4666  * This function simply calls the BUS_ADJUST_RESOURCE() method of the
4667  * parent of @p dev.
4668  */
4669 int
4670 bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start,
4671     rman_res_t end)
4672 {
4673 	if (dev->parent == NULL)
4674 		return (EINVAL);
4675 	return (BUS_ADJUST_RESOURCE(dev->parent, dev, type, r, start, end));
4676 }
4677 
4678 /**
4679  * @brief Wrapper function for BUS_ACTIVATE_RESOURCE().
4680  *
4681  * This function simply calls the BUS_ACTIVATE_RESOURCE() method of the
4682  * parent of @p dev.
4683  */
4684 int
4685 bus_activate_resource(device_t dev, int type, int rid, struct resource *r)
4686 {
4687 	if (dev->parent == NULL)
4688 		return (EINVAL);
4689 	return (BUS_ACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4690 }
4691 
4692 /**
4693  * @brief Wrapper function for BUS_DEACTIVATE_RESOURCE().
4694  *
4695  * This function simply calls the BUS_DEACTIVATE_RESOURCE() method of the
4696  * parent of @p dev.
4697  */
4698 int
4699 bus_deactivate_resource(device_t dev, int type, int rid, struct resource *r)
4700 {
4701 	if (dev->parent == NULL)
4702 		return (EINVAL);
4703 	return (BUS_DEACTIVATE_RESOURCE(dev->parent, dev, type, rid, r));
4704 }
4705 
4706 /**
4707  * @brief Wrapper function for BUS_MAP_RESOURCE().
4708  *
4709  * This function simply calls the BUS_MAP_RESOURCE() method of the
4710  * parent of @p dev.
4711  */
4712 int
4713 bus_map_resource(device_t dev, int type, struct resource *r,
4714     struct resource_map_request *args, struct resource_map *map)
4715 {
4716 	if (dev->parent == NULL)
4717 		return (EINVAL);
4718 	return (BUS_MAP_RESOURCE(dev->parent, dev, type, r, args, map));
4719 }
4720 
4721 /**
4722  * @brief Wrapper function for BUS_UNMAP_RESOURCE().
4723  *
4724  * This function simply calls the BUS_UNMAP_RESOURCE() method of the
4725  * parent of @p dev.
4726  */
4727 int
4728 bus_unmap_resource(device_t dev, int type, struct resource *r,
4729     struct resource_map *map)
4730 {
4731 	if (dev->parent == NULL)
4732 		return (EINVAL);
4733 	return (BUS_UNMAP_RESOURCE(dev->parent, dev, type, r, map));
4734 }
4735 
4736 /**
4737  * @brief Wrapper function for BUS_RELEASE_RESOURCE().
4738  *
4739  * This function simply calls the BUS_RELEASE_RESOURCE() method of the
4740  * parent of @p dev.
4741  */
4742 int
4743 bus_release_resource(device_t dev, int type, int rid, struct resource *r)
4744 {
4745 	int rv;
4746 
4747 	if (dev->parent == NULL)
4748 		return (EINVAL);
4749 	rv = BUS_RELEASE_RESOURCE(dev->parent, dev, type, rid, r);
4750 	return (rv);
4751 }
4752 
4753 /**
4754  * @brief Wrapper function for BUS_SETUP_INTR().
4755  *
4756  * This function simply calls the BUS_SETUP_INTR() method of the
4757  * parent of @p dev.
4758  */
4759 int
4760 bus_setup_intr(device_t dev, struct resource *r, int flags,
4761     driver_filter_t filter, driver_intr_t handler, void *arg, void **cookiep)
4762 {
4763 	int error;
4764 
4765 	if (dev->parent == NULL)
4766 		return (EINVAL);
4767 	error = BUS_SETUP_INTR(dev->parent, dev, r, flags, filter, handler,
4768 	    arg, cookiep);
4769 	if (error != 0)
4770 		return (error);
4771 	if (handler != NULL && !(flags & INTR_MPSAFE))
4772 		device_printf(dev, "[GIANT-LOCKED]\n");
4773 	return (0);
4774 }
4775 
4776 /**
4777  * @brief Wrapper function for BUS_TEARDOWN_INTR().
4778  *
4779  * This function simply calls the BUS_TEARDOWN_INTR() method of the
4780  * parent of @p dev.
4781  */
4782 int
4783 bus_teardown_intr(device_t dev, struct resource *r, void *cookie)
4784 {
4785 	if (dev->parent == NULL)
4786 		return (EINVAL);
4787 	return (BUS_TEARDOWN_INTR(dev->parent, dev, r, cookie));
4788 }
4789 
4790 /**
4791  * @brief Wrapper function for BUS_SUSPEND_INTR().
4792  *
4793  * This function simply calls the BUS_SUSPEND_INTR() method of the
4794  * parent of @p dev.
4795  */
4796 int
4797 bus_suspend_intr(device_t dev, struct resource *r)
4798 {
4799 	if (dev->parent == NULL)
4800 		return (EINVAL);
4801 	return (BUS_SUSPEND_INTR(dev->parent, dev, r));
4802 }
4803 
4804 /**
4805  * @brief Wrapper function for BUS_RESUME_INTR().
4806  *
4807  * This function simply calls the BUS_RESUME_INTR() method of the
4808  * parent of @p dev.
4809  */
4810 int
4811 bus_resume_intr(device_t dev, struct resource *r)
4812 {
4813 	if (dev->parent == NULL)
4814 		return (EINVAL);
4815 	return (BUS_RESUME_INTR(dev->parent, dev, r));
4816 }
4817 
4818 /**
4819  * @brief Wrapper function for BUS_BIND_INTR().
4820  *
4821  * This function simply calls the BUS_BIND_INTR() method of the
4822  * parent of @p dev.
4823  */
4824 int
4825 bus_bind_intr(device_t dev, struct resource *r, int cpu)
4826 {
4827 	if (dev->parent == NULL)
4828 		return (EINVAL);
4829 	return (BUS_BIND_INTR(dev->parent, dev, r, cpu));
4830 }
4831 
4832 /**
4833  * @brief Wrapper function for BUS_DESCRIBE_INTR().
4834  *
4835  * This function first formats the requested description into a
4836  * temporary buffer and then calls the BUS_DESCRIBE_INTR() method of
4837  * the parent of @p dev.
4838  */
4839 int
4840 bus_describe_intr(device_t dev, struct resource *irq, void *cookie,
4841     const char *fmt, ...)
4842 {
4843 	va_list ap;
4844 	char descr[MAXCOMLEN + 1];
4845 
4846 	if (dev->parent == NULL)
4847 		return (EINVAL);
4848 	va_start(ap, fmt);
4849 	vsnprintf(descr, sizeof(descr), fmt, ap);
4850 	va_end(ap);
4851 	return (BUS_DESCRIBE_INTR(dev->parent, dev, irq, cookie, descr));
4852 }
4853 
4854 /**
4855  * @brief Wrapper function for BUS_SET_RESOURCE().
4856  *
4857  * This function simply calls the BUS_SET_RESOURCE() method of the
4858  * parent of @p dev.
4859  */
4860 int
4861 bus_set_resource(device_t dev, int type, int rid,
4862     rman_res_t start, rman_res_t count)
4863 {
4864 	return (BUS_SET_RESOURCE(device_get_parent(dev), dev, type, rid,
4865 	    start, count));
4866 }
4867 
4868 /**
4869  * @brief Wrapper function for BUS_GET_RESOURCE().
4870  *
4871  * This function simply calls the BUS_GET_RESOURCE() method of the
4872  * parent of @p dev.
4873  */
4874 int
4875 bus_get_resource(device_t dev, int type, int rid,
4876     rman_res_t *startp, rman_res_t *countp)
4877 {
4878 	return (BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4879 	    startp, countp));
4880 }
4881 
4882 /**
4883  * @brief Wrapper function for BUS_GET_RESOURCE().
4884  *
4885  * This function simply calls the BUS_GET_RESOURCE() method of the
4886  * parent of @p dev and returns the start value.
4887  */
4888 rman_res_t
4889 bus_get_resource_start(device_t dev, int type, int rid)
4890 {
4891 	rman_res_t start;
4892 	rman_res_t count;
4893 	int error;
4894 
4895 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4896 	    &start, &count);
4897 	if (error)
4898 		return (0);
4899 	return (start);
4900 }
4901 
4902 /**
4903  * @brief Wrapper function for BUS_GET_RESOURCE().
4904  *
4905  * This function simply calls the BUS_GET_RESOURCE() method of the
4906  * parent of @p dev and returns the count value.
4907  */
4908 rman_res_t
4909 bus_get_resource_count(device_t dev, int type, int rid)
4910 {
4911 	rman_res_t start;
4912 	rman_res_t count;
4913 	int error;
4914 
4915 	error = BUS_GET_RESOURCE(device_get_parent(dev), dev, type, rid,
4916 	    &start, &count);
4917 	if (error)
4918 		return (0);
4919 	return (count);
4920 }
4921 
4922 /**
4923  * @brief Wrapper function for BUS_DELETE_RESOURCE().
4924  *
4925  * This function simply calls the BUS_DELETE_RESOURCE() method of the
4926  * parent of @p dev.
4927  */
4928 void
4929 bus_delete_resource(device_t dev, int type, int rid)
4930 {
4931 	BUS_DELETE_RESOURCE(device_get_parent(dev), dev, type, rid);
4932 }
4933 
4934 /**
4935  * @brief Wrapper function for BUS_CHILD_PRESENT().
4936  *
4937  * This function simply calls the BUS_CHILD_PRESENT() method of the
4938  * parent of @p dev.
4939  */
4940 int
4941 bus_child_present(device_t child)
4942 {
4943 	return (BUS_CHILD_PRESENT(device_get_parent(child), child));
4944 }
4945 
4946 /**
4947  * @brief Wrapper function for BUS_CHILD_PNPINFO_STR().
4948  *
4949  * This function simply calls the BUS_CHILD_PNPINFO_STR() method of the
4950  * parent of @p dev.
4951  */
4952 int
4953 bus_child_pnpinfo_str(device_t child, char *buf, size_t buflen)
4954 {
4955 	device_t parent;
4956 
4957 	parent = device_get_parent(child);
4958 	if (parent == NULL) {
4959 		*buf = '\0';
4960 		return (0);
4961 	}
4962 	return (BUS_CHILD_PNPINFO_STR(parent, child, buf, buflen));
4963 }
4964 
4965 /**
4966  * @brief Wrapper function for BUS_CHILD_LOCATION_STR().
4967  *
4968  * This function simply calls the BUS_CHILD_LOCATION_STR() method of the
4969  * parent of @p dev.
4970  */
4971 int
4972 bus_child_location_str(device_t child, char *buf, size_t buflen)
4973 {
4974 	device_t parent;
4975 
4976 	parent = device_get_parent(child);
4977 	if (parent == NULL) {
4978 		*buf = '\0';
4979 		return (0);
4980 	}
4981 	return (BUS_CHILD_LOCATION_STR(parent, child, buf, buflen));
4982 }
4983 
4984 /**
4985  * @brief Wrapper function for bus_child_pnpinfo_str using sbuf
4986  *
4987  * A convenient wrapper frunction for bus_child_pnpinfo_str that allows
4988  * us to splat that into an sbuf. It uses unholy knowledge of sbuf to
4989  * accomplish this, however. It is an interim function until we can convert
4990  * this interface more fully.
4991  */
4992 /* Note: we reach inside of sbuf because it's API isn't rich enough to do this */
4993 #define	SPACE(s)	((s)->s_size - (s)->s_len)
4994 #define EOB(s)		((s)->s_buf + (s)->s_len)
4995 
4996 static int
4997 bus_child_pnpinfo_sb(device_t dev, struct sbuf *sb)
4998 {
4999 	char *p;
5000 	ssize_t space;
5001 
5002 	MPASS((sb->s_flags & SBUF_INCLUDENUL) == 0);
5003 	MPASS(sb->s_size >= sb->s_len);
5004 	if (sb->s_error != 0)
5005 		return (-1);
5006 	space = SPACE(sb);
5007 	if (space <= 1) {
5008 		sb->s_error = ENOMEM;
5009 		return (-1);
5010 	}
5011 	p = EOB(sb);
5012 	*p = '\0';	/* sbuf buffer isn't NUL terminated until sbuf_finish() */
5013 	bus_child_pnpinfo_str(dev, p, space);
5014 	sb->s_len += strlen(p);
5015 	return (0);
5016 }
5017 
5018 /**
5019  * @brief Wrapper function for bus_child_pnpinfo_str using sbuf
5020  *
5021  * A convenient wrapper frunction for bus_child_pnpinfo_str that allows
5022  * us to splat that into an sbuf. It uses unholy knowledge of sbuf to
5023  * accomplish this, however. It is an interim function until we can convert
5024  * this interface more fully.
5025  */
5026 static int
5027 bus_child_location_sb(device_t dev, struct sbuf *sb)
5028 {
5029 	char *p;
5030 	ssize_t space;
5031 
5032 	MPASS((sb->s_flags & SBUF_INCLUDENUL) == 0);
5033 	MPASS(sb->s_size >= sb->s_len);
5034 	if (sb->s_error != 0)
5035 		return (-1);
5036 	space = SPACE(sb);
5037 	if (space <= 1) {
5038 		sb->s_error = ENOMEM;
5039 		return (-1);
5040 	}
5041 	p = EOB(sb);
5042 	*p = '\0';	/* sbuf buffer isn't NUL terminated until sbuf_finish() */
5043 	bus_child_location_str(dev, p, space);
5044 	sb->s_len += strlen(p);
5045 	return (0);
5046 }
5047 #undef SPACE
5048 #undef EOB
5049 
5050 /**
5051  * @brief Wrapper function for BUS_GET_CPUS().
5052  *
5053  * This function simply calls the BUS_GET_CPUS() method of the
5054  * parent of @p dev.
5055  */
5056 int
5057 bus_get_cpus(device_t dev, enum cpu_sets op, size_t setsize, cpuset_t *cpuset)
5058 {
5059 	device_t parent;
5060 
5061 	parent = device_get_parent(dev);
5062 	if (parent == NULL)
5063 		return (EINVAL);
5064 	return (BUS_GET_CPUS(parent, dev, op, setsize, cpuset));
5065 }
5066 
5067 /**
5068  * @brief Wrapper function for BUS_GET_DMA_TAG().
5069  *
5070  * This function simply calls the BUS_GET_DMA_TAG() method of the
5071  * parent of @p dev.
5072  */
5073 bus_dma_tag_t
5074 bus_get_dma_tag(device_t dev)
5075 {
5076 	device_t parent;
5077 
5078 	parent = device_get_parent(dev);
5079 	if (parent == NULL)
5080 		return (NULL);
5081 	return (BUS_GET_DMA_TAG(parent, dev));
5082 }
5083 
5084 /**
5085  * @brief Wrapper function for BUS_GET_BUS_TAG().
5086  *
5087  * This function simply calls the BUS_GET_BUS_TAG() method of the
5088  * parent of @p dev.
5089  */
5090 bus_space_tag_t
5091 bus_get_bus_tag(device_t dev)
5092 {
5093 	device_t parent;
5094 
5095 	parent = device_get_parent(dev);
5096 	if (parent == NULL)
5097 		return ((bus_space_tag_t)0);
5098 	return (BUS_GET_BUS_TAG(parent, dev));
5099 }
5100 
5101 /**
5102  * @brief Wrapper function for BUS_GET_DOMAIN().
5103  *
5104  * This function simply calls the BUS_GET_DOMAIN() method of the
5105  * parent of @p dev.
5106  */
5107 int
5108 bus_get_domain(device_t dev, int *domain)
5109 {
5110 	return (BUS_GET_DOMAIN(device_get_parent(dev), dev, domain));
5111 }
5112 
5113 /* Resume all devices and then notify userland that we're up again. */
5114 static int
5115 root_resume(device_t dev)
5116 {
5117 	int error;
5118 
5119 	error = bus_generic_resume(dev);
5120 	if (error == 0) {
5121 		devctl_notify("kern", "power", "resume", NULL); /* Deprecated gone in 14 */
5122 		devctl_notify("kernel", "power", "resume", NULL);
5123 	}
5124 	return (error);
5125 }
5126 
5127 static int
5128 root_print_child(device_t dev, device_t child)
5129 {
5130 	int	retval = 0;
5131 
5132 	retval += bus_print_child_header(dev, child);
5133 	retval += printf("\n");
5134 
5135 	return (retval);
5136 }
5137 
5138 static int
5139 root_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
5140     driver_filter_t *filter, driver_intr_t *intr, void *arg, void **cookiep)
5141 {
5142 	/*
5143 	 * If an interrupt mapping gets to here something bad has happened.
5144 	 */
5145 	panic("root_setup_intr");
5146 }
5147 
5148 /*
5149  * If we get here, assume that the device is permanent and really is
5150  * present in the system.  Removable bus drivers are expected to intercept
5151  * this call long before it gets here.  We return -1 so that drivers that
5152  * really care can check vs -1 or some ERRNO returned higher in the food
5153  * chain.
5154  */
5155 static int
5156 root_child_present(device_t dev, device_t child)
5157 {
5158 	return (-1);
5159 }
5160 
5161 static int
5162 root_get_cpus(device_t dev, device_t child, enum cpu_sets op, size_t setsize,
5163     cpuset_t *cpuset)
5164 {
5165 	switch (op) {
5166 	case INTR_CPUS:
5167 		/* Default to returning the set of all CPUs. */
5168 		if (setsize != sizeof(cpuset_t))
5169 			return (EINVAL);
5170 		*cpuset = all_cpus;
5171 		return (0);
5172 	default:
5173 		return (EINVAL);
5174 	}
5175 }
5176 
5177 static kobj_method_t root_methods[] = {
5178 	/* Device interface */
5179 	KOBJMETHOD(device_shutdown,	bus_generic_shutdown),
5180 	KOBJMETHOD(device_suspend,	bus_generic_suspend),
5181 	KOBJMETHOD(device_resume,	root_resume),
5182 
5183 	/* Bus interface */
5184 	KOBJMETHOD(bus_print_child,	root_print_child),
5185 	KOBJMETHOD(bus_read_ivar,	bus_generic_read_ivar),
5186 	KOBJMETHOD(bus_write_ivar,	bus_generic_write_ivar),
5187 	KOBJMETHOD(bus_setup_intr,	root_setup_intr),
5188 	KOBJMETHOD(bus_child_present,	root_child_present),
5189 	KOBJMETHOD(bus_get_cpus,	root_get_cpus),
5190 
5191 	KOBJMETHOD_END
5192 };
5193 
5194 static driver_t root_driver = {
5195 	"root",
5196 	root_methods,
5197 	1,			/* no softc */
5198 };
5199 
5200 device_t	root_bus;
5201 devclass_t	root_devclass;
5202 
5203 static int
5204 root_bus_module_handler(module_t mod, int what, void* arg)
5205 {
5206 	switch (what) {
5207 	case MOD_LOAD:
5208 		TAILQ_INIT(&bus_data_devices);
5209 		kobj_class_compile((kobj_class_t) &root_driver);
5210 		root_bus = make_device(NULL, "root", 0);
5211 		root_bus->desc = "System root bus";
5212 		kobj_init((kobj_t) root_bus, (kobj_class_t) &root_driver);
5213 		root_bus->driver = &root_driver;
5214 		root_bus->state = DS_ATTACHED;
5215 		root_devclass = devclass_find_internal("root", NULL, FALSE);
5216 		devinit();
5217 		return (0);
5218 
5219 	case MOD_SHUTDOWN:
5220 		device_shutdown(root_bus);
5221 		return (0);
5222 	default:
5223 		return (EOPNOTSUPP);
5224 	}
5225 
5226 	return (0);
5227 }
5228 
5229 static moduledata_t root_bus_mod = {
5230 	"rootbus",
5231 	root_bus_module_handler,
5232 	NULL
5233 };
5234 DECLARE_MODULE(rootbus, root_bus_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
5235 
5236 /**
5237  * @brief Automatically configure devices
5238  *
5239  * This function begins the autoconfiguration process by calling
5240  * device_probe_and_attach() for each child of the @c root0 device.
5241  */
5242 void
5243 root_bus_configure(void)
5244 {
5245 	PDEBUG(("."));
5246 
5247 	/* Eventually this will be split up, but this is sufficient for now. */
5248 	bus_set_pass(BUS_PASS_DEFAULT);
5249 }
5250 
5251 /**
5252  * @brief Module handler for registering device drivers
5253  *
5254  * This module handler is used to automatically register device
5255  * drivers when modules are loaded. If @p what is MOD_LOAD, it calls
5256  * devclass_add_driver() for the driver described by the
5257  * driver_module_data structure pointed to by @p arg
5258  */
5259 int
5260 driver_module_handler(module_t mod, int what, void *arg)
5261 {
5262 	struct driver_module_data *dmd;
5263 	devclass_t bus_devclass;
5264 	kobj_class_t driver;
5265 	int error, pass;
5266 
5267 	dmd = (struct driver_module_data *)arg;
5268 	bus_devclass = devclass_find_internal(dmd->dmd_busname, NULL, TRUE);
5269 	error = 0;
5270 
5271 	switch (what) {
5272 	case MOD_LOAD:
5273 		if (dmd->dmd_chainevh)
5274 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5275 
5276 		pass = dmd->dmd_pass;
5277 		driver = dmd->dmd_driver;
5278 		PDEBUG(("Loading module: driver %s on bus %s (pass %d)",
5279 		    DRIVERNAME(driver), dmd->dmd_busname, pass));
5280 		error = devclass_add_driver(bus_devclass, driver, pass,
5281 		    dmd->dmd_devclass);
5282 		break;
5283 
5284 	case MOD_UNLOAD:
5285 		PDEBUG(("Unloading module: driver %s from bus %s",
5286 		    DRIVERNAME(dmd->dmd_driver),
5287 		    dmd->dmd_busname));
5288 		error = devclass_delete_driver(bus_devclass,
5289 		    dmd->dmd_driver);
5290 
5291 		if (!error && dmd->dmd_chainevh)
5292 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5293 		break;
5294 	case MOD_QUIESCE:
5295 		PDEBUG(("Quiesce module: driver %s from bus %s",
5296 		    DRIVERNAME(dmd->dmd_driver),
5297 		    dmd->dmd_busname));
5298 		error = devclass_quiesce_driver(bus_devclass,
5299 		    dmd->dmd_driver);
5300 
5301 		if (!error && dmd->dmd_chainevh)
5302 			error = dmd->dmd_chainevh(mod,what,dmd->dmd_chainarg);
5303 		break;
5304 	default:
5305 		error = EOPNOTSUPP;
5306 		break;
5307 	}
5308 
5309 	return (error);
5310 }
5311 
5312 /**
5313  * @brief Enumerate all hinted devices for this bus.
5314  *
5315  * Walks through the hints for this bus and calls the bus_hinted_child
5316  * routine for each one it fines.  It searches first for the specific
5317  * bus that's being probed for hinted children (eg isa0), and then for
5318  * generic children (eg isa).
5319  *
5320  * @param	dev	bus device to enumerate
5321  */
5322 void
5323 bus_enumerate_hinted_children(device_t bus)
5324 {
5325 	int i;
5326 	const char *dname, *busname;
5327 	int dunit;
5328 
5329 	/*
5330 	 * enumerate all devices on the specific bus
5331 	 */
5332 	busname = device_get_nameunit(bus);
5333 	i = 0;
5334 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5335 		BUS_HINTED_CHILD(bus, dname, dunit);
5336 
5337 	/*
5338 	 * and all the generic ones.
5339 	 */
5340 	busname = device_get_name(bus);
5341 	i = 0;
5342 	while (resource_find_match(&i, &dname, &dunit, "at", busname) == 0)
5343 		BUS_HINTED_CHILD(bus, dname, dunit);
5344 }
5345 
5346 #ifdef BUS_DEBUG
5347 
5348 /* the _short versions avoid iteration by not calling anything that prints
5349  * more than oneliners. I love oneliners.
5350  */
5351 
5352 static void
5353 print_device_short(device_t dev, int indent)
5354 {
5355 	if (!dev)
5356 		return;
5357 
5358 	indentprintf(("device %d: <%s> %sparent,%schildren,%s%s%s%s%s%s,%sivars,%ssoftc,busy=%d\n",
5359 	    dev->unit, dev->desc,
5360 	    (dev->parent? "":"no "),
5361 	    (TAILQ_EMPTY(&dev->children)? "no ":""),
5362 	    (dev->flags&DF_ENABLED? "enabled,":"disabled,"),
5363 	    (dev->flags&DF_FIXEDCLASS? "fixed,":""),
5364 	    (dev->flags&DF_WILDCARD? "wildcard,":""),
5365 	    (dev->flags&DF_DESCMALLOCED? "descmalloced,":""),
5366 	    (dev->flags&DF_REBID? "rebiddable,":""),
5367 	    (dev->flags&DF_SUSPENDED? "suspended,":""),
5368 	    (dev->ivars? "":"no "),
5369 	    (dev->softc? "":"no "),
5370 	    dev->busy));
5371 }
5372 
5373 static void
5374 print_device(device_t dev, int indent)
5375 {
5376 	if (!dev)
5377 		return;
5378 
5379 	print_device_short(dev, indent);
5380 
5381 	indentprintf(("Parent:\n"));
5382 	print_device_short(dev->parent, indent+1);
5383 	indentprintf(("Driver:\n"));
5384 	print_driver_short(dev->driver, indent+1);
5385 	indentprintf(("Devclass:\n"));
5386 	print_devclass_short(dev->devclass, indent+1);
5387 }
5388 
5389 void
5390 print_device_tree_short(device_t dev, int indent)
5391 /* print the device and all its children (indented) */
5392 {
5393 	device_t child;
5394 
5395 	if (!dev)
5396 		return;
5397 
5398 	print_device_short(dev, indent);
5399 
5400 	TAILQ_FOREACH(child, &dev->children, link) {
5401 		print_device_tree_short(child, indent+1);
5402 	}
5403 }
5404 
5405 void
5406 print_device_tree(device_t dev, int indent)
5407 /* print the device and all its children (indented) */
5408 {
5409 	device_t child;
5410 
5411 	if (!dev)
5412 		return;
5413 
5414 	print_device(dev, indent);
5415 
5416 	TAILQ_FOREACH(child, &dev->children, link) {
5417 		print_device_tree(child, indent+1);
5418 	}
5419 }
5420 
5421 static void
5422 print_driver_short(driver_t *driver, int indent)
5423 {
5424 	if (!driver)
5425 		return;
5426 
5427 	indentprintf(("driver %s: softc size = %zd\n",
5428 	    driver->name, driver->size));
5429 }
5430 
5431 static void
5432 print_driver(driver_t *driver, int indent)
5433 {
5434 	if (!driver)
5435 		return;
5436 
5437 	print_driver_short(driver, indent);
5438 }
5439 
5440 static void
5441 print_driver_list(driver_list_t drivers, int indent)
5442 {
5443 	driverlink_t driver;
5444 
5445 	TAILQ_FOREACH(driver, &drivers, link) {
5446 		print_driver(driver->driver, indent);
5447 	}
5448 }
5449 
5450 static void
5451 print_devclass_short(devclass_t dc, int indent)
5452 {
5453 	if ( !dc )
5454 		return;
5455 
5456 	indentprintf(("devclass %s: max units = %d\n", dc->name, dc->maxunit));
5457 }
5458 
5459 static void
5460 print_devclass(devclass_t dc, int indent)
5461 {
5462 	int i;
5463 
5464 	if ( !dc )
5465 		return;
5466 
5467 	print_devclass_short(dc, indent);
5468 	indentprintf(("Drivers:\n"));
5469 	print_driver_list(dc->drivers, indent+1);
5470 
5471 	indentprintf(("Devices:\n"));
5472 	for (i = 0; i < dc->maxunit; i++)
5473 		if (dc->devices[i])
5474 			print_device(dc->devices[i], indent+1);
5475 }
5476 
5477 void
5478 print_devclass_list_short(void)
5479 {
5480 	devclass_t dc;
5481 
5482 	printf("Short listing of devclasses, drivers & devices:\n");
5483 	TAILQ_FOREACH(dc, &devclasses, link) {
5484 		print_devclass_short(dc, 0);
5485 	}
5486 }
5487 
5488 void
5489 print_devclass_list(void)
5490 {
5491 	devclass_t dc;
5492 
5493 	printf("Full listing of devclasses, drivers & devices:\n");
5494 	TAILQ_FOREACH(dc, &devclasses, link) {
5495 		print_devclass(dc, 0);
5496 	}
5497 }
5498 
5499 #endif
5500 
5501 /*
5502  * User-space access to the device tree.
5503  *
5504  * We implement a small set of nodes:
5505  *
5506  * hw.bus			Single integer read method to obtain the
5507  *				current generation count.
5508  * hw.bus.devices		Reads the entire device tree in flat space.
5509  * hw.bus.rman			Resource manager interface
5510  *
5511  * We might like to add the ability to scan devclasses and/or drivers to
5512  * determine what else is currently loaded/available.
5513  */
5514 
5515 static int
5516 sysctl_bus_info(SYSCTL_HANDLER_ARGS)
5517 {
5518 	struct u_businfo	ubus;
5519 
5520 	ubus.ub_version = BUS_USER_VERSION;
5521 	ubus.ub_generation = bus_data_generation;
5522 
5523 	return (SYSCTL_OUT(req, &ubus, sizeof(ubus)));
5524 }
5525 SYSCTL_PROC(_hw_bus, OID_AUTO, info, CTLTYPE_STRUCT | CTLFLAG_RD |
5526     CTLFLAG_MPSAFE, NULL, 0, sysctl_bus_info, "S,u_businfo",
5527     "bus-related data");
5528 
5529 static int
5530 sysctl_devices(SYSCTL_HANDLER_ARGS)
5531 {
5532 	struct sbuf		sb;
5533 	int			*name = (int *)arg1;
5534 	u_int			namelen = arg2;
5535 	int			index;
5536 	device_t		dev;
5537 	struct u_device		*udev;
5538 	int			error;
5539 
5540 	if (namelen != 2)
5541 		return (EINVAL);
5542 
5543 	if (bus_data_generation_check(name[0]))
5544 		return (EINVAL);
5545 
5546 	index = name[1];
5547 
5548 	/*
5549 	 * Scan the list of devices, looking for the requested index.
5550 	 */
5551 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5552 		if (index-- == 0)
5553 			break;
5554 	}
5555 	if (dev == NULL)
5556 		return (ENOENT);
5557 
5558 	/*
5559 	 * Populate the return item, careful not to overflow the buffer.
5560 	 */
5561 	udev = malloc(sizeof(*udev), M_BUS, M_WAITOK | M_ZERO);
5562 	if (udev == NULL)
5563 		return (ENOMEM);
5564 	udev->dv_handle = (uintptr_t)dev;
5565 	udev->dv_parent = (uintptr_t)dev->parent;
5566 	udev->dv_devflags = dev->devflags;
5567 	udev->dv_flags = dev->flags;
5568 	udev->dv_state = dev->state;
5569 	sbuf_new(&sb, udev->dv_fields, sizeof(udev->dv_fields), SBUF_FIXEDLEN);
5570 	if (dev->nameunit != NULL)
5571 		sbuf_cat(&sb, dev->nameunit);
5572 	sbuf_putc(&sb, '\0');
5573 	if (dev->desc != NULL)
5574 		sbuf_cat(&sb, dev->desc);
5575 	sbuf_putc(&sb, '\0');
5576 	if (dev->driver != NULL)
5577 		sbuf_cat(&sb, dev->driver->name);
5578 	sbuf_putc(&sb, '\0');
5579 	bus_child_pnpinfo_sb(dev, &sb);
5580 	sbuf_putc(&sb, '\0');
5581 	bus_child_location_sb(dev, &sb);
5582 	sbuf_putc(&sb, '\0');
5583 	error = sbuf_finish(&sb);
5584 	if (error == 0)
5585 		error = SYSCTL_OUT(req, udev, sizeof(*udev));
5586 	sbuf_delete(&sb);
5587 	free(udev, M_BUS);
5588 	return (error);
5589 }
5590 
5591 SYSCTL_NODE(_hw_bus, OID_AUTO, devices,
5592     CTLFLAG_RD | CTLFLAG_NEEDGIANT, sysctl_devices,
5593     "system device tree");
5594 
5595 int
5596 bus_data_generation_check(int generation)
5597 {
5598 	if (generation != bus_data_generation)
5599 		return (1);
5600 
5601 	/* XXX generate optimised lists here? */
5602 	return (0);
5603 }
5604 
5605 void
5606 bus_data_generation_update(void)
5607 {
5608 	atomic_add_int(&bus_data_generation, 1);
5609 }
5610 
5611 int
5612 bus_free_resource(device_t dev, int type, struct resource *r)
5613 {
5614 	if (r == NULL)
5615 		return (0);
5616 	return (bus_release_resource(dev, type, rman_get_rid(r), r));
5617 }
5618 
5619 device_t
5620 device_lookup_by_name(const char *name)
5621 {
5622 	device_t dev;
5623 
5624 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
5625 		if (dev->nameunit != NULL && strcmp(dev->nameunit, name) == 0)
5626 			return (dev);
5627 	}
5628 	return (NULL);
5629 }
5630 
5631 /*
5632  * /dev/devctl2 implementation.  The existing /dev/devctl device has
5633  * implicit semantics on open, so it could not be reused for this.
5634  * Another option would be to call this /dev/bus?
5635  */
5636 static int
5637 find_device(struct devreq *req, device_t *devp)
5638 {
5639 	device_t dev;
5640 
5641 	/*
5642 	 * First, ensure that the name is nul terminated.
5643 	 */
5644 	if (memchr(req->dr_name, '\0', sizeof(req->dr_name)) == NULL)
5645 		return (EINVAL);
5646 
5647 	/*
5648 	 * Second, try to find an attached device whose name matches
5649 	 * 'name'.
5650 	 */
5651 	dev = device_lookup_by_name(req->dr_name);
5652 	if (dev != NULL) {
5653 		*devp = dev;
5654 		return (0);
5655 	}
5656 
5657 	/* Finally, give device enumerators a chance. */
5658 	dev = NULL;
5659 	EVENTHANDLER_DIRECT_INVOKE(dev_lookup, req->dr_name, &dev);
5660 	if (dev == NULL)
5661 		return (ENOENT);
5662 	*devp = dev;
5663 	return (0);
5664 }
5665 
5666 static bool
5667 driver_exists(device_t bus, const char *driver)
5668 {
5669 	devclass_t dc;
5670 
5671 	for (dc = bus->devclass; dc != NULL; dc = dc->parent) {
5672 		if (devclass_find_driver_internal(dc, driver) != NULL)
5673 			return (true);
5674 	}
5675 	return (false);
5676 }
5677 
5678 static void
5679 device_gen_nomatch(device_t dev)
5680 {
5681 	device_t child;
5682 
5683 	if (dev->flags & DF_NEEDNOMATCH &&
5684 	    dev->state == DS_NOTPRESENT) {
5685 		BUS_PROBE_NOMATCH(dev->parent, dev);
5686 		devnomatch(dev);
5687 		dev->flags |= DF_DONENOMATCH;
5688 	}
5689 	dev->flags &= ~DF_NEEDNOMATCH;
5690 	TAILQ_FOREACH(child, &dev->children, link) {
5691 		device_gen_nomatch(child);
5692 	}
5693 }
5694 
5695 static void
5696 device_do_deferred_actions(void)
5697 {
5698 	devclass_t dc;
5699 	driverlink_t dl;
5700 
5701 	/*
5702 	 * Walk through the devclasses to find all the drivers we've tagged as
5703 	 * deferred during the freeze and call the driver added routines. They
5704 	 * have already been added to the lists in the background, so the driver
5705 	 * added routines that trigger a probe will have all the right bidders
5706 	 * for the probe auction.
5707 	 */
5708 	TAILQ_FOREACH(dc, &devclasses, link) {
5709 		TAILQ_FOREACH(dl, &dc->drivers, link) {
5710 			if (dl->flags & DL_DEFERRED_PROBE) {
5711 				devclass_driver_added(dc, dl->driver);
5712 				dl->flags &= ~DL_DEFERRED_PROBE;
5713 			}
5714 		}
5715 	}
5716 
5717 	/*
5718 	 * We also defer no-match events during a freeze. Walk the tree and
5719 	 * generate all the pent-up events that are still relevant.
5720 	 */
5721 	device_gen_nomatch(root_bus);
5722 	bus_data_generation_update();
5723 }
5724 
5725 static int
5726 devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
5727     struct thread *td)
5728 {
5729 	struct devreq *req;
5730 	device_t dev;
5731 	int error, old;
5732 
5733 	/* Locate the device to control. */
5734 	mtx_lock(&Giant);
5735 	req = (struct devreq *)data;
5736 	switch (cmd) {
5737 	case DEV_ATTACH:
5738 	case DEV_DETACH:
5739 	case DEV_ENABLE:
5740 	case DEV_DISABLE:
5741 	case DEV_SUSPEND:
5742 	case DEV_RESUME:
5743 	case DEV_SET_DRIVER:
5744 	case DEV_CLEAR_DRIVER:
5745 	case DEV_RESCAN:
5746 	case DEV_DELETE:
5747 	case DEV_RESET:
5748 		error = priv_check(td, PRIV_DRIVER);
5749 		if (error == 0)
5750 			error = find_device(req, &dev);
5751 		break;
5752 	case DEV_FREEZE:
5753 	case DEV_THAW:
5754 		error = priv_check(td, PRIV_DRIVER);
5755 		break;
5756 	default:
5757 		error = ENOTTY;
5758 		break;
5759 	}
5760 	if (error) {
5761 		mtx_unlock(&Giant);
5762 		return (error);
5763 	}
5764 
5765 	/* Perform the requested operation. */
5766 	switch (cmd) {
5767 	case DEV_ATTACH:
5768 		if (device_is_attached(dev) && (dev->flags & DF_REBID) == 0)
5769 			error = EBUSY;
5770 		else if (!device_is_enabled(dev))
5771 			error = ENXIO;
5772 		else
5773 			error = device_probe_and_attach(dev);
5774 		break;
5775 	case DEV_DETACH:
5776 		if (!device_is_attached(dev)) {
5777 			error = ENXIO;
5778 			break;
5779 		}
5780 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5781 			error = device_quiesce(dev);
5782 			if (error)
5783 				break;
5784 		}
5785 		error = device_detach(dev);
5786 		break;
5787 	case DEV_ENABLE:
5788 		if (device_is_enabled(dev)) {
5789 			error = EBUSY;
5790 			break;
5791 		}
5792 
5793 		/*
5794 		 * If the device has been probed but not attached (e.g.
5795 		 * when it has been disabled by a loader hint), just
5796 		 * attach the device rather than doing a full probe.
5797 		 */
5798 		device_enable(dev);
5799 		if (device_is_alive(dev)) {
5800 			/*
5801 			 * If the device was disabled via a hint, clear
5802 			 * the hint.
5803 			 */
5804 			if (resource_disabled(dev->driver->name, dev->unit))
5805 				resource_unset_value(dev->driver->name,
5806 				    dev->unit, "disabled");
5807 			error = device_attach(dev);
5808 		} else
5809 			error = device_probe_and_attach(dev);
5810 		break;
5811 	case DEV_DISABLE:
5812 		if (!device_is_enabled(dev)) {
5813 			error = ENXIO;
5814 			break;
5815 		}
5816 
5817 		if (!(req->dr_flags & DEVF_FORCE_DETACH)) {
5818 			error = device_quiesce(dev);
5819 			if (error)
5820 				break;
5821 		}
5822 
5823 		/*
5824 		 * Force DF_FIXEDCLASS on around detach to preserve
5825 		 * the existing name.
5826 		 */
5827 		old = dev->flags;
5828 		dev->flags |= DF_FIXEDCLASS;
5829 		error = device_detach(dev);
5830 		if (!(old & DF_FIXEDCLASS))
5831 			dev->flags &= ~DF_FIXEDCLASS;
5832 		if (error == 0)
5833 			device_disable(dev);
5834 		break;
5835 	case DEV_SUSPEND:
5836 		if (device_is_suspended(dev)) {
5837 			error = EBUSY;
5838 			break;
5839 		}
5840 		if (device_get_parent(dev) == NULL) {
5841 			error = EINVAL;
5842 			break;
5843 		}
5844 		error = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
5845 		break;
5846 	case DEV_RESUME:
5847 		if (!device_is_suspended(dev)) {
5848 			error = EINVAL;
5849 			break;
5850 		}
5851 		if (device_get_parent(dev) == NULL) {
5852 			error = EINVAL;
5853 			break;
5854 		}
5855 		error = BUS_RESUME_CHILD(device_get_parent(dev), dev);
5856 		break;
5857 	case DEV_SET_DRIVER: {
5858 		devclass_t dc;
5859 		char driver[128];
5860 
5861 		error = copyinstr(req->dr_data, driver, sizeof(driver), NULL);
5862 		if (error)
5863 			break;
5864 		if (driver[0] == '\0') {
5865 			error = EINVAL;
5866 			break;
5867 		}
5868 		if (dev->devclass != NULL &&
5869 		    strcmp(driver, dev->devclass->name) == 0)
5870 			/* XXX: Could possibly force DF_FIXEDCLASS on? */
5871 			break;
5872 
5873 		/*
5874 		 * Scan drivers for this device's bus looking for at
5875 		 * least one matching driver.
5876 		 */
5877 		if (dev->parent == NULL) {
5878 			error = EINVAL;
5879 			break;
5880 		}
5881 		if (!driver_exists(dev->parent, driver)) {
5882 			error = ENOENT;
5883 			break;
5884 		}
5885 		dc = devclass_create(driver);
5886 		if (dc == NULL) {
5887 			error = ENOMEM;
5888 			break;
5889 		}
5890 
5891 		/* Detach device if necessary. */
5892 		if (device_is_attached(dev)) {
5893 			if (req->dr_flags & DEVF_SET_DRIVER_DETACH)
5894 				error = device_detach(dev);
5895 			else
5896 				error = EBUSY;
5897 			if (error)
5898 				break;
5899 		}
5900 
5901 		/* Clear any previously-fixed device class and unit. */
5902 		if (dev->flags & DF_FIXEDCLASS)
5903 			devclass_delete_device(dev->devclass, dev);
5904 		dev->flags |= DF_WILDCARD;
5905 		dev->unit = -1;
5906 
5907 		/* Force the new device class. */
5908 		error = devclass_add_device(dc, dev);
5909 		if (error)
5910 			break;
5911 		dev->flags |= DF_FIXEDCLASS;
5912 		error = device_probe_and_attach(dev);
5913 		break;
5914 	}
5915 	case DEV_CLEAR_DRIVER:
5916 		if (!(dev->flags & DF_FIXEDCLASS)) {
5917 			error = 0;
5918 			break;
5919 		}
5920 		if (device_is_attached(dev)) {
5921 			if (req->dr_flags & DEVF_CLEAR_DRIVER_DETACH)
5922 				error = device_detach(dev);
5923 			else
5924 				error = EBUSY;
5925 			if (error)
5926 				break;
5927 		}
5928 
5929 		dev->flags &= ~DF_FIXEDCLASS;
5930 		dev->flags |= DF_WILDCARD;
5931 		devclass_delete_device(dev->devclass, dev);
5932 		error = device_probe_and_attach(dev);
5933 		break;
5934 	case DEV_RESCAN:
5935 		if (!device_is_attached(dev)) {
5936 			error = ENXIO;
5937 			break;
5938 		}
5939 		error = BUS_RESCAN(dev);
5940 		break;
5941 	case DEV_DELETE: {
5942 		device_t parent;
5943 
5944 		parent = device_get_parent(dev);
5945 		if (parent == NULL) {
5946 			error = EINVAL;
5947 			break;
5948 		}
5949 		if (!(req->dr_flags & DEVF_FORCE_DELETE)) {
5950 			if (bus_child_present(dev) != 0) {
5951 				error = EBUSY;
5952 				break;
5953 			}
5954 		}
5955 
5956 		error = device_delete_child(parent, dev);
5957 		break;
5958 	}
5959 	case DEV_FREEZE:
5960 		if (device_frozen)
5961 			error = EBUSY;
5962 		else
5963 			device_frozen = true;
5964 		break;
5965 	case DEV_THAW:
5966 		if (!device_frozen)
5967 			error = EBUSY;
5968 		else {
5969 			device_do_deferred_actions();
5970 			device_frozen = false;
5971 		}
5972 		break;
5973 	case DEV_RESET:
5974 		if ((req->dr_flags & ~(DEVF_RESET_DETACH)) != 0) {
5975 			error = EINVAL;
5976 			break;
5977 		}
5978 		error = BUS_RESET_CHILD(device_get_parent(dev), dev,
5979 		    req->dr_flags);
5980 		break;
5981 	}
5982 	mtx_unlock(&Giant);
5983 	return (error);
5984 }
5985 
5986 static struct cdevsw devctl2_cdevsw = {
5987 	.d_version =	D_VERSION,
5988 	.d_ioctl =	devctl2_ioctl,
5989 	.d_name =	"devctl2",
5990 };
5991 
5992 static void
5993 devctl2_init(void)
5994 {
5995 	make_dev_credf(MAKEDEV_ETERNAL, &devctl2_cdevsw, 0, NULL,
5996 	    UID_ROOT, GID_WHEEL, 0600, "devctl2");
5997 }
5998 
5999 /*
6000  * APIs to manage deprecation and obsolescence.
6001  */
6002 static int obsolete_panic = 0;
6003 SYSCTL_INT(_debug, OID_AUTO, obsolete_panic, CTLFLAG_RWTUN, &obsolete_panic, 0,
6004     "Panic when obsolete features are used (0 = never, 1 = if osbolete, "
6005     "2 = if deprecated)");
6006 
6007 static void
6008 gone_panic(int major, int running, const char *msg)
6009 {
6010 	switch (obsolete_panic)
6011 	{
6012 	case 0:
6013 		return;
6014 	case 1:
6015 		if (running < major)
6016 			return;
6017 		/* FALLTHROUGH */
6018 	default:
6019 		panic("%s", msg);
6020 	}
6021 }
6022 
6023 void
6024 _gone_in(int major, const char *msg)
6025 {
6026 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6027 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6028 		printf("Obsolete code will be removed soon: %s\n", msg);
6029 	else
6030 		printf("Deprecated code (to be removed in FreeBSD %d): %s\n",
6031 		    major, msg);
6032 }
6033 
6034 void
6035 _gone_in_dev(device_t dev, int major, const char *msg)
6036 {
6037 	gone_panic(major, P_OSREL_MAJOR(__FreeBSD_version), msg);
6038 	if (P_OSREL_MAJOR(__FreeBSD_version) >= major)
6039 		device_printf(dev,
6040 		    "Obsolete code will be removed soon: %s\n", msg);
6041 	else
6042 		device_printf(dev,
6043 		    "Deprecated code (to be removed in FreeBSD %d): %s\n",
6044 		    major, msg);
6045 }
6046 
6047 #ifdef DDB
6048 DB_SHOW_COMMAND(device, db_show_device)
6049 {
6050 	device_t dev;
6051 
6052 	if (!have_addr)
6053 		return;
6054 
6055 	dev = (device_t)addr;
6056 
6057 	db_printf("name:    %s\n", device_get_nameunit(dev));
6058 	db_printf("  driver:  %s\n", DRIVERNAME(dev->driver));
6059 	db_printf("  class:   %s\n", DEVCLANAME(dev->devclass));
6060 	db_printf("  addr:    %p\n", dev);
6061 	db_printf("  parent:  %p\n", dev->parent);
6062 	db_printf("  softc:   %p\n", dev->softc);
6063 	db_printf("  ivars:   %p\n", dev->ivars);
6064 }
6065 
6066 DB_SHOW_ALL_COMMAND(devices, db_show_all_devices)
6067 {
6068 	device_t dev;
6069 
6070 	TAILQ_FOREACH(dev, &bus_data_devices, devlink) {
6071 		db_show_device((db_expr_t)dev, true, count, modif);
6072 	}
6073 }
6074 #endif
6075