FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_conf.c
1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1999-2002 Poul-Henning Kamp
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 <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/systm.h>
35 #include <sys/bio.h>
36 #include <sys/devctl.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/module.h>
40 #include <sys/malloc.h>
41 #include <sys/conf.h>
42 #include <sys/vnode.h>
43 #include <sys/queue.h>
44 #include <sys/poll.h>
45 #include <sys/sx.h>
46 #include <sys/ctype.h>
47 #include <sys/ucred.h>
48 #include <sys/taskqueue.h>
49 #include <machine/stdarg.h>
50
51 #include <fs/devfs/devfs_int.h>
52 #include <vm/vm.h>
53
54 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage");
55
56 struct mtx devmtx;
57 static void destroy_devl(struct cdev *dev);
58 static int destroy_dev_sched_cbl(struct cdev *dev,
59 void (*cb)(void *), void *arg);
60 static void destroy_dev_tq(void *ctx, int pending);
61 static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw,
62 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
63 va_list ap);
64
65 static struct cdev_priv_list cdevp_free_list =
66 TAILQ_HEAD_INITIALIZER(cdevp_free_list);
67 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list =
68 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list);
69
70 void
71 dev_lock(void)
72 {
73
74 mtx_lock(&devmtx);
75 }
76
77 /*
78 * Free all the memory collected while the cdev mutex was
79 * locked. Since devmtx is after the system map mutex, free() cannot
80 * be called immediately and is postponed until cdev mutex can be
81 * dropped.
82 */
83 static void
84 dev_unlock_and_free(void)
85 {
86 struct cdev_priv_list cdp_free;
87 struct free_cdevsw csw_free;
88 struct cdev_priv *cdp;
89 struct cdevsw *csw;
90
91 dev_lock_assert_locked();
92
93 /*
94 * Make the local copy of the list heads while the dev_mtx is
95 * held. Free it later.
96 */
97 TAILQ_INIT(&cdp_free);
98 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list);
99 csw_free = cdevsw_gt_post_list;
100 SLIST_INIT(&cdevsw_gt_post_list);
101
102 mtx_unlock(&devmtx);
103
104 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) {
105 TAILQ_REMOVE(&cdp_free, cdp, cdp_list);
106 devfs_free(&cdp->cdp_c);
107 }
108 while ((csw = SLIST_FIRST(&csw_free)) != NULL) {
109 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list);
110 free(csw, M_DEVT);
111 }
112 }
113
114 static void
115 dev_free_devlocked(struct cdev *cdev)
116 {
117 struct cdev_priv *cdp;
118
119 dev_lock_assert_locked();
120 cdp = cdev2priv(cdev);
121 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0,
122 ("destroy_dev() was not called after delist_dev(%p)", cdev));
123 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list);
124 }
125
126 static void
127 cdevsw_free_devlocked(struct cdevsw *csw)
128 {
129
130 dev_lock_assert_locked();
131 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
132 }
133
134 void
135 dev_unlock(void)
136 {
137
138 mtx_unlock(&devmtx);
139 }
140
141 void
142 dev_ref(struct cdev *dev)
143 {
144
145 dev_lock_assert_unlocked();
146 mtx_lock(&devmtx);
147 dev->si_refcount++;
148 mtx_unlock(&devmtx);
149 }
150
151 void
152 dev_refl(struct cdev *dev)
153 {
154
155 dev_lock_assert_locked();
156 dev->si_refcount++;
157 }
158
159 void
160 dev_rel(struct cdev *dev)
161 {
162 int flag = 0;
163
164 dev_lock_assert_unlocked();
165 dev_lock();
166 dev->si_refcount--;
167 KASSERT(dev->si_refcount >= 0,
168 ("dev_rel(%s) gave negative count", devtoname(dev)));
169 if (dev->si_devsw == NULL && dev->si_refcount == 0) {
170 LIST_REMOVE(dev, si_list);
171 flag = 1;
172 }
173 dev_unlock();
174 if (flag)
175 devfs_free(dev);
176 }
177
178 struct cdevsw *
179 dev_refthread(struct cdev *dev, int *ref)
180 {
181 struct cdevsw *csw;
182 struct cdev_priv *cdp;
183
184 dev_lock_assert_unlocked();
185 if ((dev->si_flags & SI_ETERNAL) != 0) {
186 *ref = 0;
187 return (dev->si_devsw);
188 }
189 cdp = cdev2priv(dev);
190 mtx_lock(&cdp->cdp_threadlock);
191 csw = dev->si_devsw;
192 if (csw != NULL) {
193 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0)
194 atomic_add_long(&dev->si_threadcount, 1);
195 else
196 csw = NULL;
197 }
198 mtx_unlock(&cdp->cdp_threadlock);
199 if (csw != NULL)
200 *ref = 1;
201 return (csw);
202 }
203
204 struct cdevsw *
205 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref)
206 {
207 struct cdevsw *csw;
208 struct cdev_priv *cdp;
209 struct cdev *dev;
210
211 dev_lock_assert_unlocked();
212 if ((vp->v_vflag & VV_ETERNALDEV) != 0) {
213 dev = vp->v_rdev;
214 if (dev == NULL)
215 return (NULL);
216 KASSERT((dev->si_flags & SI_ETERNAL) != 0,
217 ("Not eternal cdev"));
218 *ref = 0;
219 csw = dev->si_devsw;
220 KASSERT(csw != NULL, ("Eternal cdev is destroyed"));
221 *devp = dev;
222 return (csw);
223 }
224
225 csw = NULL;
226 VI_LOCK(vp);
227 dev = vp->v_rdev;
228 if (dev == NULL) {
229 VI_UNLOCK(vp);
230 return (NULL);
231 }
232 cdp = cdev2priv(dev);
233 mtx_lock(&cdp->cdp_threadlock);
234 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
235 csw = dev->si_devsw;
236 if (csw != NULL)
237 atomic_add_long(&dev->si_threadcount, 1);
238 }
239 mtx_unlock(&cdp->cdp_threadlock);
240 VI_UNLOCK(vp);
241 if (csw != NULL) {
242 *devp = dev;
243 *ref = 1;
244 }
245 return (csw);
246 }
247
248 void
249 dev_relthread(struct cdev *dev, int ref)
250 {
251
252 dev_lock_assert_unlocked();
253 if (!ref)
254 return;
255 KASSERT(dev->si_threadcount > 0,
256 ("%s threadcount is wrong", dev->si_name));
257 atomic_subtract_rel_long(&dev->si_threadcount, 1);
258 }
259
260 int
261 nullop(void)
262 {
263
264 return (0);
265 }
266
267 int
268 eopnotsupp(void)
269 {
270
271 return (EOPNOTSUPP);
272 }
273
274 static int
275 enxio(void)
276 {
277 return (ENXIO);
278 }
279
280 static int
281 enodev(void)
282 {
283 return (ENODEV);
284 }
285
286 /* Define a dead_cdevsw for use when devices leave unexpectedly. */
287
288 #define dead_open (d_open_t *)enxio
289 #define dead_close (d_close_t *)enxio
290 #define dead_read (d_read_t *)enxio
291 #define dead_write (d_write_t *)enxio
292 #define dead_ioctl (d_ioctl_t *)enxio
293 #define dead_poll (d_poll_t *)enodev
294 #define dead_mmap (d_mmap_t *)enodev
295
296 static void
297 dead_strategy(struct bio *bp)
298 {
299
300 biofinish(bp, NULL, ENXIO);
301 }
302
303 #define dead_dump (dumper_t *)enxio
304 #define dead_kqfilter (d_kqfilter_t *)enxio
305 #define dead_mmap_single (d_mmap_single_t *)enodev
306
307 static struct cdevsw dead_cdevsw = {
308 .d_version = D_VERSION,
309 .d_open = dead_open,
310 .d_close = dead_close,
311 .d_read = dead_read,
312 .d_write = dead_write,
313 .d_ioctl = dead_ioctl,
314 .d_poll = dead_poll,
315 .d_mmap = dead_mmap,
316 .d_strategy = dead_strategy,
317 .d_name = "dead",
318 .d_dump = dead_dump,
319 .d_kqfilter = dead_kqfilter,
320 .d_mmap_single = dead_mmap_single
321 };
322
323 /* Default methods if driver does not specify method */
324
325 #define null_open (d_open_t *)nullop
326 #define null_close (d_close_t *)nullop
327 #define no_read (d_read_t *)enodev
328 #define no_write (d_write_t *)enodev
329 #define no_ioctl (d_ioctl_t *)enodev
330 #define no_mmap (d_mmap_t *)enodev
331 #define no_kqfilter (d_kqfilter_t *)enodev
332 #define no_mmap_single (d_mmap_single_t *)enodev
333
334 static void
335 no_strategy(struct bio *bp)
336 {
337
338 biofinish(bp, NULL, ENODEV);
339 }
340
341 static int
342 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
343 {
344
345 return (poll_no_poll(events));
346 }
347
348 #define no_dump (dumper_t *)enodev
349
350 static int
351 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
352 {
353 struct cdevsw *dsw;
354 int ref, retval;
355
356 dsw = dev_refthread(dev, &ref);
357 if (dsw == NULL)
358 return (ENXIO);
359 mtx_lock(&Giant);
360 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
361 mtx_unlock(&Giant);
362 dev_relthread(dev, ref);
363 return (retval);
364 }
365
366 static int
367 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
368 {
369 struct cdevsw *dsw;
370 int ref, retval;
371
372 dsw = dev_refthread(dev, &ref);
373 if (dsw == NULL)
374 return (ENXIO);
375 mtx_lock(&Giant);
376 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
377 mtx_unlock(&Giant);
378 dev_relthread(dev, ref);
379 return (retval);
380 }
381
382 static int
383 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
384 {
385 struct cdevsw *dsw;
386 int ref, retval;
387
388 dsw = dev_refthread(dev, &ref);
389 if (dsw == NULL)
390 return (ENXIO);
391 mtx_lock(&Giant);
392 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
393 mtx_unlock(&Giant);
394 dev_relthread(dev, ref);
395 return (retval);
396 }
397
398 static void
399 giant_strategy(struct bio *bp)
400 {
401 struct cdevsw *dsw;
402 struct cdev *dev;
403 int ref;
404
405 dev = bp->bio_dev;
406 dsw = dev_refthread(dev, &ref);
407 if (dsw == NULL) {
408 biofinish(bp, NULL, ENXIO);
409 return;
410 }
411 mtx_lock(&Giant);
412 dsw->d_gianttrick->d_strategy(bp);
413 mtx_unlock(&Giant);
414 dev_relthread(dev, ref);
415 }
416
417 static int
418 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
419 {
420 struct cdevsw *dsw;
421 int ref, retval;
422
423 dsw = dev_refthread(dev, &ref);
424 if (dsw == NULL)
425 return (ENXIO);
426 mtx_lock(&Giant);
427 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
428 mtx_unlock(&Giant);
429 dev_relthread(dev, ref);
430 return (retval);
431 }
432
433 static int
434 giant_read(struct cdev *dev, struct uio *uio, int ioflag)
435 {
436 struct cdevsw *dsw;
437 int ref, retval;
438
439 dsw = dev_refthread(dev, &ref);
440 if (dsw == NULL)
441 return (ENXIO);
442 mtx_lock(&Giant);
443 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
444 mtx_unlock(&Giant);
445 dev_relthread(dev, ref);
446 return (retval);
447 }
448
449 static int
450 giant_write(struct cdev *dev, struct uio *uio, int ioflag)
451 {
452 struct cdevsw *dsw;
453 int ref, retval;
454
455 dsw = dev_refthread(dev, &ref);
456 if (dsw == NULL)
457 return (ENXIO);
458 mtx_lock(&Giant);
459 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
460 mtx_unlock(&Giant);
461 dev_relthread(dev, ref);
462 return (retval);
463 }
464
465 static int
466 giant_poll(struct cdev *dev, int events, struct thread *td)
467 {
468 struct cdevsw *dsw;
469 int ref, retval;
470
471 dsw = dev_refthread(dev, &ref);
472 if (dsw == NULL)
473 return (ENXIO);
474 mtx_lock(&Giant);
475 retval = dsw->d_gianttrick->d_poll(dev, events, td);
476 mtx_unlock(&Giant);
477 dev_relthread(dev, ref);
478 return (retval);
479 }
480
481 static int
482 giant_kqfilter(struct cdev *dev, struct knote *kn)
483 {
484 struct cdevsw *dsw;
485 int ref, retval;
486
487 dsw = dev_refthread(dev, &ref);
488 if (dsw == NULL)
489 return (ENXIO);
490 mtx_lock(&Giant);
491 retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
492 mtx_unlock(&Giant);
493 dev_relthread(dev, ref);
494 return (retval);
495 }
496
497 static int
498 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot,
499 vm_memattr_t *memattr)
500 {
501 struct cdevsw *dsw;
502 int ref, retval;
503
504 dsw = dev_refthread(dev, &ref);
505 if (dsw == NULL)
506 return (ENXIO);
507 mtx_lock(&Giant);
508 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot,
509 memattr);
510 mtx_unlock(&Giant);
511 dev_relthread(dev, ref);
512 return (retval);
513 }
514
515 static int
516 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size,
517 vm_object_t *object, int nprot)
518 {
519 struct cdevsw *dsw;
520 int ref, retval;
521
522 dsw = dev_refthread(dev, &ref);
523 if (dsw == NULL)
524 return (ENXIO);
525 mtx_lock(&Giant);
526 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object,
527 nprot);
528 mtx_unlock(&Giant);
529 dev_relthread(dev, ref);
530 return (retval);
531 }
532
533 static void
534 notify(struct cdev *dev, const char *ev, int flags)
535 {
536 static const char prefix[] = "cdev=";
537 char *data;
538 int namelen, mflags;
539
540 if (cold)
541 return;
542 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
543 namelen = strlen(dev->si_name);
544 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags);
545 if (data == NULL)
546 return;
547 memcpy(data, prefix, sizeof(prefix) - 1);
548 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1);
549 devctl_notify("DEVFS", "CDEV", ev, data);
550 free(data, M_TEMP);
551 }
552
553 static void
554 notify_create(struct cdev *dev, int flags)
555 {
556
557 notify(dev, "CREATE", flags);
558 }
559
560 static void
561 notify_destroy(struct cdev *dev)
562 {
563
564 notify(dev, "DESTROY", MAKEDEV_WAITOK);
565 }
566
567 static struct cdev *
568 newdev(struct make_dev_args *args, struct cdev *si)
569 {
570 struct cdev *si2;
571 struct cdevsw *csw;
572
573 dev_lock_assert_locked();
574 csw = args->mda_devsw;
575 si2 = NULL;
576 if (csw->d_flags & D_NEEDMINOR) {
577 /* We may want to return an existing device */
578 LIST_FOREACH(si2, &csw->d_devs, si_list) {
579 if (dev2unit(si2) == args->mda_unit) {
580 dev_free_devlocked(si);
581 si = si2;
582 break;
583 }
584 }
585
586 /*
587 * If we're returning an existing device, we should make sure
588 * it isn't already initialized. This would have been caught
589 * in consumers anyways, but it's good to catch such a case
590 * early. We still need to complete initialization of the
591 * device, and we'll use whatever make_dev_args were passed in
592 * to do so.
593 */
594 KASSERT(si2 == NULL || (si2->si_flags & SI_NAMED) == 0,
595 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
596 args->mda_devsw->d_name, dev2unit(si2), devtoname(si2)));
597 }
598 si->si_drv0 = args->mda_unit;
599 si->si_drv1 = args->mda_si_drv1;
600 si->si_drv2 = args->mda_si_drv2;
601 /* Only push to csw->d_devs if it's not a cloned device. */
602 if (si2 == NULL) {
603 si->si_devsw = csw;
604 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
605 } else {
606 KASSERT(si->si_devsw == csw,
607 ("%s: inconsistent devsw between clone_create() and make_dev()",
608 __func__));
609 }
610 return (si);
611 }
612
613 static void
614 fini_cdevsw(struct cdevsw *devsw)
615 {
616 struct cdevsw *gt;
617
618 if (devsw->d_gianttrick != NULL) {
619 gt = devsw->d_gianttrick;
620 memcpy(devsw, gt, sizeof *devsw);
621 cdevsw_free_devlocked(gt);
622 devsw->d_gianttrick = NULL;
623 }
624 devsw->d_flags &= ~D_INIT;
625 }
626
627 static int
628 prep_cdevsw(struct cdevsw *devsw, int flags)
629 {
630 struct cdevsw *dsw2;
631
632 dev_lock_assert_locked();
633 if (devsw->d_flags & D_INIT)
634 return (0);
635 if (devsw->d_flags & D_NEEDGIANT) {
636 dev_unlock();
637 dsw2 = malloc(sizeof *dsw2, M_DEVT,
638 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
639 dev_lock();
640 if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
641 return (ENOMEM);
642 } else
643 dsw2 = NULL;
644 if (devsw->d_flags & D_INIT) {
645 if (dsw2 != NULL)
646 cdevsw_free_devlocked(dsw2);
647 return (0);
648 }
649
650 if (devsw->d_version != D_VERSION_04) {
651 printf(
652 "WARNING: Device driver \"%s\" has wrong version %s\n",
653 devsw->d_name == NULL ? "???" : devsw->d_name,
654 "and is disabled. Recompile KLD module.");
655 devsw->d_open = dead_open;
656 devsw->d_close = dead_close;
657 devsw->d_read = dead_read;
658 devsw->d_write = dead_write;
659 devsw->d_ioctl = dead_ioctl;
660 devsw->d_poll = dead_poll;
661 devsw->d_mmap = dead_mmap;
662 devsw->d_mmap_single = dead_mmap_single;
663 devsw->d_strategy = dead_strategy;
664 devsw->d_dump = dead_dump;
665 devsw->d_kqfilter = dead_kqfilter;
666 }
667
668 if ((devsw->d_flags & D_NEEDGIANT) != 0) {
669 if ((devsw->d_flags & D_GIANTOK) == 0) {
670 printf(
671 "WARNING: Device \"%s\" is Giant locked and may be "
672 "deleted before FreeBSD 14.0.\n",
673 devsw->d_name == NULL ? "???" : devsw->d_name);
674 }
675 if (devsw->d_gianttrick == NULL) {
676 memcpy(dsw2, devsw, sizeof *dsw2);
677 devsw->d_gianttrick = dsw2;
678 dsw2 = NULL;
679 }
680 }
681
682 #define FIXUP(member, noop, giant) \
683 do { \
684 if (devsw->member == NULL) { \
685 devsw->member = noop; \
686 } else if (devsw->d_flags & D_NEEDGIANT) \
687 devsw->member = giant; \
688 } \
689 while (0)
690
691 FIXUP(d_open, null_open, giant_open);
692 FIXUP(d_fdopen, NULL, giant_fdopen);
693 FIXUP(d_close, null_close, giant_close);
694 FIXUP(d_read, no_read, giant_read);
695 FIXUP(d_write, no_write, giant_write);
696 FIXUP(d_ioctl, no_ioctl, giant_ioctl);
697 FIXUP(d_poll, no_poll, giant_poll);
698 FIXUP(d_mmap, no_mmap, giant_mmap);
699 FIXUP(d_strategy, no_strategy, giant_strategy);
700 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter);
701 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single);
702
703 if (devsw->d_dump == NULL) devsw->d_dump = no_dump;
704
705 LIST_INIT(&devsw->d_devs);
706
707 devsw->d_flags |= D_INIT;
708
709 if (dsw2 != NULL)
710 cdevsw_free_devlocked(dsw2);
711 return (0);
712 }
713
714 static int
715 prep_devname(struct cdev *dev, const char *fmt, va_list ap)
716 {
717 int len;
718 char *from, *q, *s, *to;
719
720 dev_lock_assert_locked();
721
722 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap);
723 if (len > sizeof(dev->si_name) - 1)
724 return (ENAMETOOLONG);
725
726 /* Strip leading slashes. */
727 for (from = dev->si_name; *from == '/'; from++)
728 ;
729
730 for (to = dev->si_name; *from != '\0'; from++, to++) {
731 /*
732 * Spaces and double quotation marks cause
733 * problems for the devctl(4) protocol.
734 * Reject names containing those characters.
735 */
736 if (isspace(*from) || *from == '"')
737 return (EINVAL);
738 /* Treat multiple sequential slashes as single. */
739 while (from[0] == '/' && from[1] == '/')
740 from++;
741 /* Trailing slash is considered invalid. */
742 if (from[0] == '/' && from[1] == '\0')
743 return (EINVAL);
744 *to = *from;
745 }
746 *to = '\0';
747
748 if (dev->si_name[0] == '\0')
749 return (EINVAL);
750
751 /* Disallow "." and ".." components. */
752 for (s = dev->si_name;;) {
753 for (q = s; *q != '/' && *q != '\0'; q++)
754 ;
755 if (q - s == 1 && s[0] == '.')
756 return (EINVAL);
757 if (q - s == 2 && s[0] == '.' && s[1] == '.')
758 return (EINVAL);
759 if (*q != '/')
760 break;
761 s = q + 1;
762 }
763
764 if (devfs_dev_exists(dev->si_name) != 0)
765 return (EEXIST);
766
767 return (0);
768 }
769
770 void
771 make_dev_args_init_impl(struct make_dev_args *args, size_t sz)
772 {
773
774 bzero(args, sz);
775 args->mda_size = sz;
776 }
777
778 static int
779 make_dev_sv(struct make_dev_args *args1, struct cdev **dres,
780 const char *fmt, va_list ap)
781 {
782 struct cdev *dev, *dev_new;
783 struct make_dev_args args;
784 int res;
785
786 bzero(&args, sizeof(args));
787 if (sizeof(args) < args1->mda_size)
788 return (EINVAL);
789 bcopy(args1, &args, args1->mda_size);
790 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 ||
791 (args.mda_flags & MAKEDEV_NOWAIT) == 0,
792 ("make_dev_sv: both WAITOK and NOWAIT specified"));
793 dev_new = devfs_alloc(args.mda_flags);
794 if (dev_new == NULL)
795 return (ENOMEM);
796 dev_lock();
797 res = prep_cdevsw(args.mda_devsw, args.mda_flags);
798 if (res != 0) {
799 dev_unlock();
800 devfs_free(dev_new);
801 return (res);
802 }
803 dev = newdev(&args, dev_new);
804 if ((dev->si_flags & SI_NAMED) == 0) {
805 res = prep_devname(dev, fmt, ap);
806 if (res != 0) {
807 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) {
808 panic(
809 "make_dev_sv: bad si_name (error=%d, si_name=%s)",
810 res, dev->si_name);
811 }
812 if (dev == dev_new) {
813 LIST_REMOVE(dev, si_list);
814 dev_unlock();
815 devfs_free(dev);
816 } else
817 dev_unlock();
818 return (res);
819 }
820 }
821 if ((args.mda_flags & MAKEDEV_REF) != 0)
822 dev_refl(dev);
823 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0)
824 dev->si_flags |= SI_ETERNAL;
825 KASSERT(!(dev->si_flags & SI_NAMED),
826 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
827 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev)));
828 dev->si_flags |= SI_NAMED;
829 if (args.mda_cr != NULL)
830 dev->si_cred = crhold(args.mda_cr);
831 dev->si_uid = args.mda_uid;
832 dev->si_gid = args.mda_gid;
833 dev->si_mode = args.mda_mode;
834
835 devfs_create(dev);
836 clean_unrhdrl(devfs_inos);
837 dev_unlock_and_free();
838
839 notify_create(dev, args.mda_flags);
840
841 *dres = dev;
842 return (0);
843 }
844
845 int
846 make_dev_s(struct make_dev_args *args, struct cdev **dres,
847 const char *fmt, ...)
848 {
849 va_list ap;
850 int res;
851
852 va_start(ap, fmt);
853 res = make_dev_sv(args, dres, fmt, ap);
854 va_end(ap);
855 return (res);
856 }
857
858 static int
859 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
860 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
861 va_list ap)
862 {
863 struct make_dev_args args;
864
865 make_dev_args_init(&args);
866 args.mda_flags = flags;
867 args.mda_devsw = devsw;
868 args.mda_cr = cr;
869 args.mda_uid = uid;
870 args.mda_gid = gid;
871 args.mda_mode = mode;
872 args.mda_unit = unit;
873 return (make_dev_sv(&args, dres, fmt, ap));
874 }
875
876 struct cdev *
877 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
878 const char *fmt, ...)
879 {
880 struct cdev *dev;
881 va_list ap;
882 int res __unused;
883
884 va_start(ap, fmt);
885 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
886 ap);
887 va_end(ap);
888 KASSERT(res == 0 && dev != NULL,
889 ("make_dev: failed make_dev_credv (error=%d)", res));
890 return (dev);
891 }
892
893 struct cdev *
894 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
895 gid_t gid, int mode, const char *fmt, ...)
896 {
897 struct cdev *dev;
898 va_list ap;
899 int res __unused;
900
901 va_start(ap, fmt);
902 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
903 va_end(ap);
904
905 KASSERT(res == 0 && dev != NULL,
906 ("make_dev_cred: failed make_dev_credv (error=%d)", res));
907 return (dev);
908 }
909
910 struct cdev *
911 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
912 uid_t uid, gid_t gid, int mode, const char *fmt, ...)
913 {
914 struct cdev *dev;
915 va_list ap;
916 int res;
917
918 va_start(ap, fmt);
919 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
920 fmt, ap);
921 va_end(ap);
922
923 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
924 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
925 ("make_dev_credf: failed make_dev_credv (error=%d)", res));
926 return (res == 0 ? dev : NULL);
927 }
928
929 int
930 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw,
931 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
932 {
933 va_list ap;
934 int res;
935
936 va_start(ap, fmt);
937 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
938 fmt, ap);
939 va_end(ap);
940
941 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
942 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
943 ("make_dev_p: failed make_dev_credv (error=%d)", res));
944 return (res);
945 }
946
947 static void
948 dev_dependsl(struct cdev *pdev, struct cdev *cdev)
949 {
950
951 cdev->si_parent = pdev;
952 cdev->si_flags |= SI_CHILD;
953 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
954 }
955
956 void
957 dev_depends(struct cdev *pdev, struct cdev *cdev)
958 {
959
960 dev_lock();
961 dev_dependsl(pdev, cdev);
962 dev_unlock();
963 }
964
965 static int
966 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
967 const char *fmt, va_list ap)
968 {
969 struct cdev *dev;
970 int error;
971
972 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL"));
973 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
974 ("make_dev_alias_v: both WAITOK and NOWAIT specified"));
975 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT |
976 MAKEDEV_CHECKNAME)) == 0,
977 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags));
978
979 dev = devfs_alloc(flags);
980 if (dev == NULL)
981 return (ENOMEM);
982 dev_lock();
983 dev->si_flags |= SI_ALIAS;
984 error = prep_devname(dev, fmt, ap);
985 if (error != 0) {
986 if ((flags & MAKEDEV_CHECKNAME) == 0) {
987 panic("make_dev_alias_v: bad si_name "
988 "(error=%d, si_name=%s)", error, dev->si_name);
989 }
990 dev_unlock();
991 devfs_free(dev);
992 return (error);
993 }
994 dev->si_flags |= SI_NAMED;
995 devfs_create(dev);
996 dev_dependsl(pdev, dev);
997 clean_unrhdrl(devfs_inos);
998 dev_unlock();
999
1000 notify_create(dev, flags);
1001 *cdev = dev;
1002
1003 return (0);
1004 }
1005
1006 struct cdev *
1007 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
1008 {
1009 struct cdev *dev;
1010 va_list ap;
1011 int res __unused;
1012
1013 va_start(ap, fmt);
1014 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
1015 va_end(ap);
1016
1017 KASSERT(res == 0 && dev != NULL,
1018 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
1019 return (dev);
1020 }
1021
1022 int
1023 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
1024 const char *fmt, ...)
1025 {
1026 va_list ap;
1027 int res;
1028
1029 va_start(ap, fmt);
1030 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
1031 va_end(ap);
1032 return (res);
1033 }
1034
1035 int
1036 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
1037 struct cdev *old_alias, const char *physpath)
1038 {
1039 char *devfspath;
1040 int physpath_len;
1041 int max_parentpath_len;
1042 int parentpath_len;
1043 int devfspathbuf_len;
1044 int mflags;
1045 int ret;
1046
1047 *cdev = NULL;
1048 devfspath = NULL;
1049 physpath_len = strlen(physpath);
1050 ret = EINVAL;
1051 if (physpath_len == 0)
1052 goto out;
1053
1054 if (strncmp("id1,", physpath, 4) == 0) {
1055 physpath += 4;
1056 physpath_len -= 4;
1057 if (physpath_len == 0)
1058 goto out;
1059 }
1060
1061 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
1062 parentpath_len = strlen(pdev->si_name);
1063 if (max_parentpath_len < parentpath_len) {
1064 if (bootverbose)
1065 printf("WARNING: Unable to alias %s "
1066 "to %s/%s - path too long\n",
1067 pdev->si_name, physpath, pdev->si_name);
1068 ret = ENAMETOOLONG;
1069 goto out;
1070 }
1071
1072 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
1073 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1;
1074 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags);
1075 if (devfspath == NULL) {
1076 ret = ENOMEM;
1077 goto out;
1078 }
1079
1080 sprintf(devfspath, "%s/%s", physpath, pdev->si_name);
1081 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) {
1082 /* Retain the existing alias. */
1083 *cdev = old_alias;
1084 old_alias = NULL;
1085 ret = 0;
1086 } else {
1087 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1088 }
1089 out:
1090 if (old_alias != NULL)
1091 destroy_dev(old_alias);
1092 if (devfspath != NULL)
1093 free(devfspath, M_DEVBUF);
1094 return (ret);
1095 }
1096
1097 static void
1098 destroy_devl(struct cdev *dev)
1099 {
1100 struct cdevsw *csw;
1101 struct cdev_privdata *p;
1102 struct cdev_priv *cdp;
1103
1104 dev_lock_assert_locked();
1105 KASSERT(dev->si_flags & SI_NAMED,
1106 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
1107 KASSERT((dev->si_flags & SI_ETERNAL) == 0,
1108 ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
1109 dev2unit(dev)));
1110
1111 cdp = cdev2priv(dev);
1112 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1113 /*
1114 * Avoid race with dev_rel(), e.g. from the populate
1115 * loop. If CDP_UNREF_DTR flag is set, the reference
1116 * to be dropped at the end of destroy_devl() was
1117 * already taken by delist_dev_locked().
1118 */
1119 dev_refl(dev);
1120
1121 devfs_destroy(dev);
1122 }
1123
1124 /* Remove name marking */
1125 dev->si_flags &= ~SI_NAMED;
1126
1127 /* If we are a child, remove us from the parents list */
1128 if (dev->si_flags & SI_CHILD) {
1129 LIST_REMOVE(dev, si_siblings);
1130 dev->si_flags &= ~SI_CHILD;
1131 }
1132
1133 /* Kill our children */
1134 while (!LIST_EMPTY(&dev->si_children))
1135 destroy_devl(LIST_FIRST(&dev->si_children));
1136
1137 /* Remove from clone list */
1138 if (dev->si_flags & SI_CLONELIST) {
1139 LIST_REMOVE(dev, si_clone);
1140 dev->si_flags &= ~SI_CLONELIST;
1141 }
1142
1143 mtx_lock(&cdp->cdp_threadlock);
1144 csw = dev->si_devsw;
1145 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */
1146 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
1147 csw->d_purge(dev);
1148 mtx_unlock(&cdp->cdp_threadlock);
1149 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
1150 mtx_lock(&cdp->cdp_threadlock);
1151 if (dev->si_threadcount)
1152 printf("Still %lu threads in %s\n",
1153 dev->si_threadcount, devtoname(dev));
1154 }
1155 while (dev->si_threadcount != 0) {
1156 /* Use unique dummy wait ident */
1157 mtx_unlock(&cdp->cdp_threadlock);
1158 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
1159 mtx_lock(&cdp->cdp_threadlock);
1160 }
1161
1162 mtx_unlock(&cdp->cdp_threadlock);
1163 dev_unlock();
1164 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1165 /* avoid out of order notify events */
1166 notify_destroy(dev);
1167 }
1168 mtx_lock(&cdevpriv_mtx);
1169 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) {
1170 devfs_destroy_cdevpriv(p);
1171 mtx_lock(&cdevpriv_mtx);
1172 }
1173 mtx_unlock(&cdevpriv_mtx);
1174 dev_lock();
1175
1176 dev->si_drv1 = 0;
1177 dev->si_drv2 = 0;
1178
1179 if (!(dev->si_flags & SI_ALIAS)) {
1180 /* Remove from cdevsw list */
1181 LIST_REMOVE(dev, si_list);
1182
1183 /* If cdevsw has no more struct cdev *'s, clean it */
1184 if (LIST_EMPTY(&csw->d_devs)) {
1185 fini_cdevsw(csw);
1186 wakeup(&csw->d_devs);
1187 }
1188 }
1189 dev->si_flags &= ~SI_ALIAS;
1190 cdp->cdp_flags &= ~CDP_UNREF_DTR;
1191 dev->si_refcount--;
1192
1193 if (dev->si_refcount > 0)
1194 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1195 else
1196 dev_free_devlocked(dev);
1197 }
1198
1199 static void
1200 delist_dev_locked(struct cdev *dev)
1201 {
1202 struct cdev_priv *cdp;
1203 struct cdev *child;
1204
1205 dev_lock_assert_locked();
1206 cdp = cdev2priv(dev);
1207 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0)
1208 return;
1209 cdp->cdp_flags |= CDP_UNREF_DTR;
1210 dev_refl(dev);
1211 devfs_destroy(dev);
1212 LIST_FOREACH(child, &dev->si_children, si_siblings)
1213 delist_dev_locked(child);
1214 dev_unlock();
1215 /* ensure the destroy event is queued in order */
1216 notify_destroy(dev);
1217 dev_lock();
1218 }
1219
1220 /*
1221 * This function will delist a character device and its children from
1222 * the directory listing and create a destroy event without waiting
1223 * for all character device references to go away. At some later point
1224 * destroy_dev() must be called to complete the character device
1225 * destruction. After calling this function the character device name
1226 * can instantly be re-used.
1227 */
1228 void
1229 delist_dev(struct cdev *dev)
1230 {
1231
1232 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev");
1233 dev_lock();
1234 delist_dev_locked(dev);
1235 dev_unlock();
1236 }
1237
1238 void
1239 destroy_dev(struct cdev *dev)
1240 {
1241
1242 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1243 dev_lock();
1244 destroy_devl(dev);
1245 dev_unlock_and_free();
1246 }
1247
1248 const char *
1249 devtoname(struct cdev *dev)
1250 {
1251
1252 return (dev->si_name);
1253 }
1254
1255 int
1256 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1257 {
1258 int u, i;
1259
1260 i = strlen(stem);
1261 if (strncmp(stem, name, i) != 0)
1262 return (0);
1263 if (!isdigit(name[i]))
1264 return (0);
1265 u = 0;
1266 if (name[i] == '' && isdigit(name[i+1]))
1267 return (0);
1268 while (isdigit(name[i])) {
1269 u *= 10;
1270 u += name[i++] - '';
1271 }
1272 if (u > 0xffffff)
1273 return (0);
1274 *unit = u;
1275 if (namep)
1276 *namep = &name[i];
1277 if (name[i])
1278 return (2);
1279 return (1);
1280 }
1281
1282 /*
1283 * Helper functions for cloning device drivers.
1284 *
1285 * The objective here is to make it unnecessary for the device drivers to
1286 * use rman or similar to manage their unit number space. Due to the way
1287 * we do "on-demand" devices, using rman or other "private" methods
1288 * will be very tricky to lock down properly once we lock down this file.
1289 *
1290 * Instead we give the drivers these routines which puts the struct cdev *'s
1291 * that are to be managed on their own list, and gives the driver the ability
1292 * to ask for the first free unit number or a given specified unit number.
1293 *
1294 * In addition these routines support paired devices (pty, nmdm and similar)
1295 * by respecting a number of "flag" bits in the minor number.
1296 *
1297 */
1298
1299 struct clonedevs {
1300 LIST_HEAD(,cdev) head;
1301 };
1302
1303 void
1304 clone_setup(struct clonedevs **cdp)
1305 {
1306
1307 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1308 LIST_INIT(&(*cdp)->head);
1309 }
1310
1311 int
1312 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1313 struct cdev **dp, int extra)
1314 {
1315 struct clonedevs *cd;
1316 struct cdev *dev, *ndev, *dl, *de;
1317 struct make_dev_args args;
1318 int unit, low, u;
1319
1320 KASSERT(*cdp != NULL,
1321 ("clone_setup() not called in driver \"%s\"", csw->d_name));
1322 KASSERT(!(extra & CLONE_UNITMASK),
1323 ("Illegal extra bits (0x%x) in clone_create", extra));
1324 KASSERT(*up <= CLONE_UNITMASK,
1325 ("Too high unit (0x%x) in clone_create", *up));
1326 KASSERT(csw->d_flags & D_NEEDMINOR,
1327 ("clone_create() on cdevsw without minor numbers"));
1328
1329 /*
1330 * Search the list for a lot of things in one go:
1331 * A preexisting match is returned immediately.
1332 * The lowest free unit number if we are passed -1, and the place
1333 * in the list where we should insert that new element.
1334 * The place to insert a specified unit number, if applicable
1335 * the end of the list.
1336 */
1337 unit = *up;
1338 ndev = devfs_alloc(MAKEDEV_WAITOK);
1339 dev_lock();
1340 prep_cdevsw(csw, MAKEDEV_WAITOK);
1341 low = extra;
1342 de = dl = NULL;
1343 cd = *cdp;
1344 LIST_FOREACH(dev, &cd->head, si_clone) {
1345 KASSERT(dev->si_flags & SI_CLONELIST,
1346 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1347 u = dev2unit(dev);
1348 if (u == (unit | extra)) {
1349 *dp = dev;
1350 dev_unlock();
1351 devfs_free(ndev);
1352 return (0);
1353 }
1354 if (unit == -1 && u == low) {
1355 low++;
1356 de = dev;
1357 continue;
1358 } else if (u < (unit | extra)) {
1359 de = dev;
1360 continue;
1361 } else if (u > (unit | extra)) {
1362 dl = dev;
1363 break;
1364 }
1365 }
1366 if (unit == -1)
1367 unit = low & CLONE_UNITMASK;
1368 make_dev_args_init(&args);
1369 args.mda_unit = unit | extra;
1370 args.mda_devsw = csw;
1371 dev = newdev(&args, ndev);
1372 if (dev->si_flags & SI_CLONELIST) {
1373 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1374 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1375 LIST_FOREACH(dev, &cd->head, si_clone) {
1376 printf("\t%p %s\n", dev, dev->si_name);
1377 }
1378 panic("foo");
1379 }
1380 KASSERT(!(dev->si_flags & SI_CLONELIST),
1381 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1382 if (dl != NULL)
1383 LIST_INSERT_BEFORE(dl, dev, si_clone);
1384 else if (de != NULL)
1385 LIST_INSERT_AFTER(de, dev, si_clone);
1386 else
1387 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1388 dev->si_flags |= SI_CLONELIST;
1389 *up = unit;
1390 dev_unlock_and_free();
1391 return (1);
1392 }
1393
1394 /*
1395 * Kill everything still on the list. The driver should already have
1396 * disposed of any softc hung of the struct cdev *'s at this time.
1397 */
1398 void
1399 clone_cleanup(struct clonedevs **cdp)
1400 {
1401 struct cdev *dev;
1402 struct cdev_priv *cp;
1403 struct clonedevs *cd;
1404
1405 cd = *cdp;
1406 if (cd == NULL)
1407 return;
1408 dev_lock();
1409 while (!LIST_EMPTY(&cd->head)) {
1410 dev = LIST_FIRST(&cd->head);
1411 LIST_REMOVE(dev, si_clone);
1412 KASSERT(dev->si_flags & SI_CLONELIST,
1413 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1414 dev->si_flags &= ~SI_CLONELIST;
1415 cp = cdev2priv(dev);
1416 if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1417 cp->cdp_flags |= CDP_SCHED_DTR;
1418 KASSERT(dev->si_flags & SI_NAMED,
1419 ("Driver has goofed in cloning underways udev %jx unit %x",
1420 (uintmax_t)dev2udev(dev), dev2unit(dev)));
1421 destroy_devl(dev);
1422 }
1423 }
1424 dev_unlock_and_free();
1425 free(cd, M_DEVBUF);
1426 *cdp = NULL;
1427 }
1428
1429 static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1430 TAILQ_HEAD_INITIALIZER(dev_ddtr);
1431 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL);
1432
1433 static void
1434 destroy_dev_tq(void *ctx, int pending)
1435 {
1436 struct cdev_priv *cp;
1437 struct cdev *dev;
1438 void (*cb)(void *);
1439 void *cb_arg;
1440
1441 dev_lock();
1442 while (!TAILQ_EMPTY(&dev_ddtr)) {
1443 cp = TAILQ_FIRST(&dev_ddtr);
1444 dev = &cp->cdp_c;
1445 KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1446 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1447 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list);
1448 cb = cp->cdp_dtr_cb;
1449 cb_arg = cp->cdp_dtr_cb_arg;
1450 destroy_devl(dev);
1451 dev_unlock_and_free();
1452 dev_rel(dev);
1453 if (cb != NULL)
1454 cb(cb_arg);
1455 dev_lock();
1456 }
1457 dev_unlock();
1458 }
1459
1460 /*
1461 * devmtx shall be locked on entry. devmtx will be unlocked after
1462 * function return.
1463 */
1464 static int
1465 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1466 {
1467 struct cdev_priv *cp;
1468
1469 dev_lock_assert_locked();
1470 cp = cdev2priv(dev);
1471 if (cp->cdp_flags & CDP_SCHED_DTR) {
1472 dev_unlock();
1473 return (0);
1474 }
1475 dev_refl(dev);
1476 cp->cdp_flags |= CDP_SCHED_DTR;
1477 cp->cdp_dtr_cb = cb;
1478 cp->cdp_dtr_cb_arg = arg;
1479 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1480 dev_unlock();
1481 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1482 return (1);
1483 }
1484
1485 int
1486 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1487 {
1488
1489 dev_lock();
1490 return (destroy_dev_sched_cbl(dev, cb, arg));
1491 }
1492
1493 int
1494 destroy_dev_sched(struct cdev *dev)
1495 {
1496
1497 return (destroy_dev_sched_cb(dev, NULL, NULL));
1498 }
1499
1500 void
1501 destroy_dev_drain(struct cdevsw *csw)
1502 {
1503
1504 dev_lock();
1505 while (!LIST_EMPTY(&csw->d_devs)) {
1506 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1507 }
1508 dev_unlock();
1509 }
1510
1511 void
1512 drain_dev_clone_events(void)
1513 {
1514
1515 sx_xlock(&clone_drain_lock);
1516 sx_xunlock(&clone_drain_lock);
1517 }
1518
1519 #include "opt_ddb.h"
1520 #ifdef DDB
1521 #include <sys/kernel.h>
1522
1523 #include <ddb/ddb.h>
1524
1525 DB_SHOW_COMMAND(cdev, db_show_cdev)
1526 {
1527 struct cdev_priv *cdp;
1528 struct cdev *dev;
1529 u_int flags;
1530 char buf[512];
1531
1532 if (!have_addr) {
1533 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1534 dev = &cdp->cdp_c;
1535 db_printf("%s %p\n", dev->si_name, dev);
1536 if (db_pager_quit)
1537 break;
1538 }
1539 return;
1540 }
1541
1542 dev = (struct cdev *)addr;
1543 cdp = cdev2priv(dev);
1544 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n",
1545 dev->si_name, dev->si_refcount, dev->si_usecount,
1546 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first);
1547 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n",
1548 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2);
1549 flags = dev->si_flags;
1550 #define SI_FLAG(flag) do { \
1551 if (flags & (flag)) { \
1552 if (buf[0] != '\0') \
1553 strlcat(buf, ", ", sizeof(buf)); \
1554 strlcat(buf, (#flag) + 3, sizeof(buf)); \
1555 flags &= ~(flag); \
1556 } \
1557 } while (0)
1558 buf[0] = '\0';
1559 SI_FLAG(SI_ETERNAL);
1560 SI_FLAG(SI_ALIAS);
1561 SI_FLAG(SI_NAMED);
1562 SI_FLAG(SI_CHILD);
1563 SI_FLAG(SI_DUMPDEV);
1564 SI_FLAG(SI_CLONELIST);
1565 db_printf("si_flags %s\n", buf);
1566
1567 flags = cdp->cdp_flags;
1568 #define CDP_FLAG(flag) do { \
1569 if (flags & (flag)) { \
1570 if (buf[0] != '\0') \
1571 strlcat(buf, ", ", sizeof(buf)); \
1572 strlcat(buf, (#flag) + 4, sizeof(buf)); \
1573 flags &= ~(flag); \
1574 } \
1575 } while (0)
1576 buf[0] = '\0';
1577 CDP_FLAG(CDP_ACTIVE);
1578 CDP_FLAG(CDP_SCHED_DTR);
1579 db_printf("cdp_flags %s\n", buf);
1580 }
1581 #endif
Cache object: f60fb201eb6a936ea45cd912f7f96e44
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