2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1999-2002 Poul-Henning Kamp
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/systm.h>
38 #include <sys/mutex.h>
39 #include <sys/module.h>
40 #include <sys/malloc.h>
42 #include <sys/vnode.h>
43 #include <sys/queue.h>
46 #include <sys/ctype.h>
47 #include <sys/ucred.h>
48 #include <sys/taskqueue.h>
49 #include <machine/stdarg.h>
51 #include <fs/devfs/devfs_int.h>
54 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage");
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,
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);
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
84 dev_unlock_and_free(void)
86 struct cdev_priv_list cdp_free;
87 struct free_cdevsw csw_free;
88 struct cdev_priv *cdp;
91 mtx_assert(&devmtx, MA_OWNED);
94 * Make the local copy of the list heads while the dev_mtx is
95 * held. Free it later.
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);
104 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) {
105 TAILQ_REMOVE(&cdp_free, cdp, cdp_list);
106 devfs_free(&cdp->cdp_c);
108 while ((csw = SLIST_FIRST(&csw_free)) != NULL) {
109 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list);
115 dev_free_devlocked(struct cdev *cdev)
117 struct cdev_priv *cdp;
119 mtx_assert(&devmtx, MA_OWNED);
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);
127 cdevsw_free_devlocked(struct cdevsw *csw)
130 mtx_assert(&devmtx, MA_OWNED);
131 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
142 dev_ref(struct cdev *dev)
145 mtx_assert(&devmtx, MA_NOTOWNED);
152 dev_refl(struct cdev *dev)
155 mtx_assert(&devmtx, MA_OWNED);
160 dev_rel(struct cdev *dev)
164 mtx_assert(&devmtx, MA_NOTOWNED);
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);
179 dev_refthread(struct cdev *dev, int *ref)
182 struct cdev_priv *cdp;
184 mtx_assert(&devmtx, MA_NOTOWNED);
185 if ((dev->si_flags & SI_ETERNAL) != 0) {
187 return (dev->si_devsw);
189 cdp = cdev2priv(dev);
190 mtx_lock(&cdp->cdp_threadlock);
193 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0)
194 atomic_add_long(&dev->si_threadcount, 1);
198 mtx_unlock(&cdp->cdp_threadlock);
204 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref)
207 struct cdev_priv *cdp;
210 mtx_assert(&devmtx, MA_NOTOWNED);
211 if ((vp->v_vflag & VV_ETERNALDEV) != 0) {
215 KASSERT((dev->si_flags & SI_ETERNAL) != 0,
216 ("Not eternal cdev"));
219 KASSERT(csw != NULL, ("Eternal cdev is destroyed"));
231 cdp = cdev2priv(dev);
232 mtx_lock(&cdp->cdp_threadlock);
233 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
236 atomic_add_long(&dev->si_threadcount, 1);
238 mtx_unlock(&cdp->cdp_threadlock);
248 dev_relthread(struct cdev *dev, int ref)
251 mtx_assert(&devmtx, MA_NOTOWNED);
254 KASSERT(dev->si_threadcount > 0,
255 ("%s threadcount is wrong", dev->si_name));
256 atomic_subtract_rel_long(&dev->si_threadcount, 1);
285 /* Define a dead_cdevsw for use when devices leave unexpectedly. */
287 #define dead_open (d_open_t *)enxio
288 #define dead_close (d_close_t *)enxio
289 #define dead_read (d_read_t *)enxio
290 #define dead_write (d_write_t *)enxio
291 #define dead_ioctl (d_ioctl_t *)enxio
292 #define dead_poll (d_poll_t *)enodev
293 #define dead_mmap (d_mmap_t *)enodev
296 dead_strategy(struct bio *bp)
299 biofinish(bp, NULL, ENXIO);
302 #define dead_dump (dumper_t *)enxio
303 #define dead_kqfilter (d_kqfilter_t *)enxio
304 #define dead_mmap_single (d_mmap_single_t *)enodev
306 static struct cdevsw dead_cdevsw = {
307 .d_version = D_VERSION,
309 .d_close = dead_close,
311 .d_write = dead_write,
312 .d_ioctl = dead_ioctl,
315 .d_strategy = dead_strategy,
318 .d_kqfilter = dead_kqfilter,
319 .d_mmap_single = dead_mmap_single
322 /* Default methods if driver does not specify method */
324 #define null_open (d_open_t *)nullop
325 #define null_close (d_close_t *)nullop
326 #define no_read (d_read_t *)enodev
327 #define no_write (d_write_t *)enodev
328 #define no_ioctl (d_ioctl_t *)enodev
329 #define no_mmap (d_mmap_t *)enodev
330 #define no_kqfilter (d_kqfilter_t *)enodev
331 #define no_mmap_single (d_mmap_single_t *)enodev
334 no_strategy(struct bio *bp)
337 biofinish(bp, NULL, ENODEV);
341 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
344 return (poll_no_poll(events));
347 #define no_dump (dumper_t *)enodev
350 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
355 dsw = dev_refthread(dev, &ref);
359 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
361 dev_relthread(dev, ref);
366 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
371 dsw = dev_refthread(dev, &ref);
375 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
377 dev_relthread(dev, ref);
382 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
387 dsw = dev_refthread(dev, &ref);
391 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
393 dev_relthread(dev, ref);
398 giant_strategy(struct bio *bp)
405 dsw = dev_refthread(dev, &ref);
407 biofinish(bp, NULL, ENXIO);
411 dsw->d_gianttrick->d_strategy(bp);
413 dev_relthread(dev, ref);
417 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
422 dsw = dev_refthread(dev, &ref);
426 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
428 dev_relthread(dev, ref);
433 giant_read(struct cdev *dev, struct uio *uio, int ioflag)
438 dsw = dev_refthread(dev, &ref);
442 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
444 dev_relthread(dev, ref);
449 giant_write(struct cdev *dev, struct uio *uio, int ioflag)
454 dsw = dev_refthread(dev, &ref);
458 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
460 dev_relthread(dev, ref);
465 giant_poll(struct cdev *dev, int events, struct thread *td)
470 dsw = dev_refthread(dev, &ref);
474 retval = dsw->d_gianttrick->d_poll(dev, events, td);
476 dev_relthread(dev, ref);
481 giant_kqfilter(struct cdev *dev, struct knote *kn)
486 dsw = dev_refthread(dev, &ref);
490 retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
492 dev_relthread(dev, ref);
497 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot,
498 vm_memattr_t *memattr)
503 dsw = dev_refthread(dev, &ref);
507 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot,
510 dev_relthread(dev, ref);
515 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size,
516 vm_object_t *object, int nprot)
521 dsw = dev_refthread(dev, &ref);
525 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object,
528 dev_relthread(dev, ref);
533 notify(struct cdev *dev, const char *ev, int flags)
535 static const char prefix[] = "cdev=";
541 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
542 namelen = strlen(dev->si_name);
543 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags);
546 memcpy(data, prefix, sizeof(prefix) - 1);
547 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1);
548 devctl_notify_f("DEVFS", "CDEV", ev, data, mflags);
553 notify_create(struct cdev *dev, int flags)
556 notify(dev, "CREATE", flags);
560 notify_destroy(struct cdev *dev)
563 notify(dev, "DESTROY", MAKEDEV_WAITOK);
567 newdev(struct make_dev_args *args, struct cdev *si)
572 mtx_assert(&devmtx, MA_OWNED);
573 csw = args->mda_devsw;
575 if (csw->d_flags & D_NEEDMINOR) {
576 /* We may want to return an existing device */
577 LIST_FOREACH(si2, &csw->d_devs, si_list) {
578 if (dev2unit(si2) == args->mda_unit) {
579 dev_free_devlocked(si);
586 * If we're returning an existing device, we should make sure
587 * it isn't already initialized. This would have been caught
588 * in consumers anyways, but it's good to catch such a case
589 * early. We still need to complete initialization of the
590 * device, and we'll use whatever make_dev_args were passed in
593 KASSERT(si2 == NULL || (si2->si_flags & SI_NAMED) == 0,
594 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
595 args->mda_devsw->d_name, dev2unit(si2), devtoname(si2)));
597 si->si_drv0 = args->mda_unit;
598 si->si_drv1 = args->mda_si_drv1;
599 si->si_drv2 = args->mda_si_drv2;
600 /* Only push to csw->d_devs if it's not a cloned device. */
603 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
605 KASSERT(si->si_devsw == csw,
606 ("%s: inconsistent devsw between clone_create() and make_dev()",
613 fini_cdevsw(struct cdevsw *devsw)
617 if (devsw->d_gianttrick != NULL) {
618 gt = devsw->d_gianttrick;
619 memcpy(devsw, gt, sizeof *devsw);
620 cdevsw_free_devlocked(gt);
621 devsw->d_gianttrick = NULL;
623 devsw->d_flags &= ~D_INIT;
627 prep_cdevsw(struct cdevsw *devsw, int flags)
631 mtx_assert(&devmtx, MA_OWNED);
632 if (devsw->d_flags & D_INIT)
634 if (devsw->d_flags & D_NEEDGIANT) {
636 dsw2 = malloc(sizeof *dsw2, M_DEVT,
637 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
639 if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
643 if (devsw->d_flags & D_INIT) {
645 cdevsw_free_devlocked(dsw2);
649 if (devsw->d_version != D_VERSION_03) {
651 "WARNING: Device driver \"%s\" has wrong version %s\n",
652 devsw->d_name == NULL ? "???" : devsw->d_name,
653 "and is disabled. Recompile KLD module.");
654 devsw->d_open = dead_open;
655 devsw->d_close = dead_close;
656 devsw->d_read = dead_read;
657 devsw->d_write = dead_write;
658 devsw->d_ioctl = dead_ioctl;
659 devsw->d_poll = dead_poll;
660 devsw->d_mmap = dead_mmap;
661 devsw->d_mmap_single = dead_mmap_single;
662 devsw->d_strategy = dead_strategy;
663 devsw->d_dump = dead_dump;
664 devsw->d_kqfilter = dead_kqfilter;
667 if (devsw->d_flags & D_NEEDGIANT) {
668 if (devsw->d_gianttrick == NULL) {
669 memcpy(dsw2, devsw, sizeof *dsw2);
670 devsw->d_gianttrick = dsw2;
675 #define FIXUP(member, noop, giant) \
677 if (devsw->member == NULL) { \
678 devsw->member = noop; \
679 } else if (devsw->d_flags & D_NEEDGIANT) \
680 devsw->member = giant; \
684 FIXUP(d_open, null_open, giant_open);
685 FIXUP(d_fdopen, NULL, giant_fdopen);
686 FIXUP(d_close, null_close, giant_close);
687 FIXUP(d_read, no_read, giant_read);
688 FIXUP(d_write, no_write, giant_write);
689 FIXUP(d_ioctl, no_ioctl, giant_ioctl);
690 FIXUP(d_poll, no_poll, giant_poll);
691 FIXUP(d_mmap, no_mmap, giant_mmap);
692 FIXUP(d_strategy, no_strategy, giant_strategy);
693 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter);
694 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single);
696 if (devsw->d_dump == NULL) devsw->d_dump = no_dump;
698 LIST_INIT(&devsw->d_devs);
700 devsw->d_flags |= D_INIT;
703 cdevsw_free_devlocked(dsw2);
708 prep_devname(struct cdev *dev, const char *fmt, va_list ap)
711 char *from, *q, *s, *to;
713 mtx_assert(&devmtx, MA_OWNED);
715 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap);
716 if (len > sizeof(dev->si_name) - 1)
717 return (ENAMETOOLONG);
719 /* Strip leading slashes. */
720 for (from = dev->si_name; *from == '/'; from++)
723 for (to = dev->si_name; *from != '\0'; from++, to++) {
725 * Spaces and double quotation marks cause
726 * problems for the devctl(4) protocol.
727 * Reject names containing those characters.
729 if (isspace(*from) || *from == '"')
731 /* Treat multiple sequential slashes as single. */
732 while (from[0] == '/' && from[1] == '/')
734 /* Trailing slash is considered invalid. */
735 if (from[0] == '/' && from[1] == '\0')
741 if (dev->si_name[0] == '\0')
744 /* Disallow "." and ".." components. */
745 for (s = dev->si_name;;) {
746 for (q = s; *q != '/' && *q != '\0'; q++)
748 if (q - s == 1 && s[0] == '.')
750 if (q - s == 2 && s[0] == '.' && s[1] == '.')
757 if (devfs_dev_exists(dev->si_name) != 0)
764 make_dev_args_init_impl(struct make_dev_args *args, size_t sz)
772 make_dev_sv(struct make_dev_args *args1, struct cdev **dres,
773 const char *fmt, va_list ap)
775 struct cdev *dev, *dev_new;
776 struct make_dev_args args;
779 bzero(&args, sizeof(args));
780 if (sizeof(args) < args1->mda_size)
782 bcopy(args1, &args, args1->mda_size);
783 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 ||
784 (args.mda_flags & MAKEDEV_NOWAIT) == 0,
785 ("make_dev_sv: both WAITOK and NOWAIT specified"));
786 dev_new = devfs_alloc(args.mda_flags);
790 res = prep_cdevsw(args.mda_devsw, args.mda_flags);
796 dev = newdev(&args, dev_new);
797 if ((dev->si_flags & SI_NAMED) == 0) {
798 res = prep_devname(dev, fmt, ap);
800 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) {
802 "make_dev_sv: bad si_name (error=%d, si_name=%s)",
805 if (dev == dev_new) {
806 LIST_REMOVE(dev, si_list);
814 if ((args.mda_flags & MAKEDEV_REF) != 0)
816 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0)
817 dev->si_flags |= SI_ETERNAL;
818 KASSERT(!(dev->si_flags & SI_NAMED),
819 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
820 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev)));
821 dev->si_flags |= SI_NAMED;
822 if (args.mda_cr != NULL)
823 dev->si_cred = crhold(args.mda_cr);
824 dev->si_uid = args.mda_uid;
825 dev->si_gid = args.mda_gid;
826 dev->si_mode = args.mda_mode;
829 clean_unrhdrl(devfs_inos);
830 dev_unlock_and_free();
832 notify_create(dev, args.mda_flags);
839 make_dev_s(struct make_dev_args *args, struct cdev **dres,
840 const char *fmt, ...)
846 res = make_dev_sv(args, dres, fmt, ap);
852 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
853 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
856 struct make_dev_args args;
858 make_dev_args_init(&args);
859 args.mda_flags = flags;
860 args.mda_devsw = devsw;
864 args.mda_mode = mode;
865 args.mda_unit = unit;
866 return (make_dev_sv(&args, dres, fmt, ap));
870 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
871 const char *fmt, ...)
878 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
881 KASSERT(res == 0 && dev != NULL,
882 ("make_dev: failed make_dev_credv (error=%d)", res));
887 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
888 gid_t gid, int mode, const char *fmt, ...)
895 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
898 KASSERT(res == 0 && dev != NULL,
899 ("make_dev_cred: failed make_dev_credv (error=%d)", res));
904 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
905 uid_t uid, gid_t gid, int mode, const char *fmt, ...)
912 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
916 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
917 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
918 ("make_dev_credf: failed make_dev_credv (error=%d)", res));
919 return (res == 0 ? dev : NULL);
923 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw,
924 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
930 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
934 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
935 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
936 ("make_dev_p: failed make_dev_credv (error=%d)", res));
941 dev_dependsl(struct cdev *pdev, struct cdev *cdev)
944 cdev->si_parent = pdev;
945 cdev->si_flags |= SI_CHILD;
946 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
951 dev_depends(struct cdev *pdev, struct cdev *cdev)
955 dev_dependsl(pdev, cdev);
960 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
961 const char *fmt, va_list ap)
966 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL"));
967 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
968 ("make_dev_alias_v: both WAITOK and NOWAIT specified"));
969 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT |
970 MAKEDEV_CHECKNAME)) == 0,
971 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags));
973 dev = devfs_alloc(flags);
977 dev->si_flags |= SI_ALIAS;
978 error = prep_devname(dev, fmt, ap);
980 if ((flags & MAKEDEV_CHECKNAME) == 0) {
981 panic("make_dev_alias_v: bad si_name "
982 "(error=%d, si_name=%s)", error, dev->si_name);
988 dev->si_flags |= SI_NAMED;
990 dev_dependsl(pdev, dev);
991 clean_unrhdrl(devfs_inos);
994 notify_create(dev, flags);
1001 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
1008 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
1011 KASSERT(res == 0 && dev != NULL,
1012 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
1017 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
1018 const char *fmt, ...)
1024 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
1030 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
1031 struct cdev *old_alias, const char *physpath)
1035 int max_parentpath_len;
1037 int devfspathbuf_len;
1043 physpath_len = strlen(physpath);
1045 if (physpath_len == 0)
1048 if (strncmp("id1,", physpath, 4) == 0) {
1051 if (physpath_len == 0)
1055 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
1056 parentpath_len = strlen(pdev->si_name);
1057 if (max_parentpath_len < parentpath_len) {
1059 printf("WARNING: Unable to alias %s "
1060 "to %s/%s - path too long\n",
1061 pdev->si_name, physpath, pdev->si_name);
1066 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
1067 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1;
1068 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags);
1069 if (devfspath == NULL) {
1074 sprintf(devfspath, "%s/%s", physpath, pdev->si_name);
1075 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) {
1076 /* Retain the existing alias. */
1081 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1084 if (old_alias != NULL)
1085 destroy_dev(old_alias);
1086 if (devfspath != NULL)
1087 free(devfspath, M_DEVBUF);
1092 destroy_devl(struct cdev *dev)
1095 struct cdev_privdata *p;
1096 struct cdev_priv *cdp;
1098 mtx_assert(&devmtx, MA_OWNED);
1099 KASSERT(dev->si_flags & SI_NAMED,
1100 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
1101 KASSERT((dev->si_flags & SI_ETERNAL) == 0,
1102 ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
1105 cdp = cdev2priv(dev);
1106 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1108 * Avoid race with dev_rel(), e.g. from the populate
1109 * loop. If CDP_UNREF_DTR flag is set, the reference
1110 * to be dropped at the end of destroy_devl() was
1111 * already taken by delist_dev_locked().
1118 /* Remove name marking */
1119 dev->si_flags &= ~SI_NAMED;
1121 /* If we are a child, remove us from the parents list */
1122 if (dev->si_flags & SI_CHILD) {
1123 LIST_REMOVE(dev, si_siblings);
1124 dev->si_flags &= ~SI_CHILD;
1127 /* Kill our children */
1128 while (!LIST_EMPTY(&dev->si_children))
1129 destroy_devl(LIST_FIRST(&dev->si_children));
1131 /* Remove from clone list */
1132 if (dev->si_flags & SI_CLONELIST) {
1133 LIST_REMOVE(dev, si_clone);
1134 dev->si_flags &= ~SI_CLONELIST;
1137 mtx_lock(&cdp->cdp_threadlock);
1138 csw = dev->si_devsw;
1139 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */
1140 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
1142 mtx_unlock(&cdp->cdp_threadlock);
1143 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
1144 mtx_lock(&cdp->cdp_threadlock);
1145 if (dev->si_threadcount)
1146 printf("Still %lu threads in %s\n",
1147 dev->si_threadcount, devtoname(dev));
1149 while (dev->si_threadcount != 0) {
1150 /* Use unique dummy wait ident */
1151 mtx_unlock(&cdp->cdp_threadlock);
1152 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
1153 mtx_lock(&cdp->cdp_threadlock);
1156 mtx_unlock(&cdp->cdp_threadlock);
1158 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1159 /* avoid out of order notify events */
1160 notify_destroy(dev);
1162 mtx_lock(&cdevpriv_mtx);
1163 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) {
1164 devfs_destroy_cdevpriv(p);
1165 mtx_lock(&cdevpriv_mtx);
1167 mtx_unlock(&cdevpriv_mtx);
1172 bzero(&dev->__si_u, sizeof(dev->__si_u));
1174 if (!(dev->si_flags & SI_ALIAS)) {
1175 /* Remove from cdevsw list */
1176 LIST_REMOVE(dev, si_list);
1178 /* If cdevsw has no more struct cdev *'s, clean it */
1179 if (LIST_EMPTY(&csw->d_devs)) {
1181 wakeup(&csw->d_devs);
1184 dev->si_flags &= ~SI_ALIAS;
1185 cdp->cdp_flags &= ~CDP_UNREF_DTR;
1188 if (dev->si_refcount > 0)
1189 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1191 dev_free_devlocked(dev);
1195 delist_dev_locked(struct cdev *dev)
1197 struct cdev_priv *cdp;
1200 mtx_assert(&devmtx, MA_OWNED);
1201 cdp = cdev2priv(dev);
1202 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0)
1204 cdp->cdp_flags |= CDP_UNREF_DTR;
1207 LIST_FOREACH(child, &dev->si_children, si_siblings)
1208 delist_dev_locked(child);
1210 /* ensure the destroy event is queued in order */
1211 notify_destroy(dev);
1216 * This function will delist a character device and its children from
1217 * the directory listing and create a destroy event without waiting
1218 * for all character device references to go away. At some later point
1219 * destroy_dev() must be called to complete the character device
1220 * destruction. After calling this function the character device name
1221 * can instantly be re-used.
1224 delist_dev(struct cdev *dev)
1227 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev");
1229 delist_dev_locked(dev);
1234 destroy_dev(struct cdev *dev)
1237 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1240 dev_unlock_and_free();
1244 devtoname(struct cdev *dev)
1247 return (dev->si_name);
1251 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1256 if (bcmp(stem, name, i) != 0)
1258 if (!isdigit(name[i]))
1261 if (name[i] == '0' && isdigit(name[i+1]))
1263 while (isdigit(name[i])) {
1265 u += name[i++] - '0';
1278 * Helper functions for cloning device drivers.
1280 * The objective here is to make it unnecessary for the device drivers to
1281 * use rman or similar to manage their unit number space. Due to the way
1282 * we do "on-demand" devices, using rman or other "private" methods
1283 * will be very tricky to lock down properly once we lock down this file.
1285 * Instead we give the drivers these routines which puts the struct cdev *'s
1286 * that are to be managed on their own list, and gives the driver the ability
1287 * to ask for the first free unit number or a given specified unit number.
1289 * In addition these routines support paired devices (pty, nmdm and similar)
1290 * by respecting a number of "flag" bits in the minor number.
1295 LIST_HEAD(,cdev) head;
1299 clone_setup(struct clonedevs **cdp)
1302 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1303 LIST_INIT(&(*cdp)->head);
1307 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1308 struct cdev **dp, int extra)
1310 struct clonedevs *cd;
1311 struct cdev *dev, *ndev, *dl, *de;
1312 struct make_dev_args args;
1315 KASSERT(*cdp != NULL,
1316 ("clone_setup() not called in driver \"%s\"", csw->d_name));
1317 KASSERT(!(extra & CLONE_UNITMASK),
1318 ("Illegal extra bits (0x%x) in clone_create", extra));
1319 KASSERT(*up <= CLONE_UNITMASK,
1320 ("Too high unit (0x%x) in clone_create", *up));
1321 KASSERT(csw->d_flags & D_NEEDMINOR,
1322 ("clone_create() on cdevsw without minor numbers"));
1326 * Search the list for a lot of things in one go:
1327 * A preexisting match is returned immediately.
1328 * The lowest free unit number if we are passed -1, and the place
1329 * in the list where we should insert that new element.
1330 * The place to insert a specified unit number, if applicable
1331 * the end of the list.
1334 ndev = devfs_alloc(MAKEDEV_WAITOK);
1336 prep_cdevsw(csw, MAKEDEV_WAITOK);
1340 LIST_FOREACH(dev, &cd->head, si_clone) {
1341 KASSERT(dev->si_flags & SI_CLONELIST,
1342 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1344 if (u == (unit | extra)) {
1350 if (unit == -1 && u == low) {
1354 } else if (u < (unit | extra)) {
1357 } else if (u > (unit | extra)) {
1363 unit = low & CLONE_UNITMASK;
1364 make_dev_args_init(&args);
1365 args.mda_unit = unit | extra;
1366 args.mda_devsw = csw;
1367 dev = newdev(&args, ndev);
1368 if (dev->si_flags & SI_CLONELIST) {
1369 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1370 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1371 LIST_FOREACH(dev, &cd->head, si_clone) {
1372 printf("\t%p %s\n", dev, dev->si_name);
1376 KASSERT(!(dev->si_flags & SI_CLONELIST),
1377 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1379 LIST_INSERT_BEFORE(dl, dev, si_clone);
1380 else if (de != NULL)
1381 LIST_INSERT_AFTER(de, dev, si_clone);
1383 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1384 dev->si_flags |= SI_CLONELIST;
1386 dev_unlock_and_free();
1391 * Kill everything still on the list. The driver should already have
1392 * disposed of any softc hung of the struct cdev *'s at this time.
1395 clone_cleanup(struct clonedevs **cdp)
1398 struct cdev_priv *cp;
1399 struct clonedevs *cd;
1405 while (!LIST_EMPTY(&cd->head)) {
1406 dev = LIST_FIRST(&cd->head);
1407 LIST_REMOVE(dev, si_clone);
1408 KASSERT(dev->si_flags & SI_CLONELIST,
1409 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1410 dev->si_flags &= ~SI_CLONELIST;
1411 cp = cdev2priv(dev);
1412 if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1413 cp->cdp_flags |= CDP_SCHED_DTR;
1414 KASSERT(dev->si_flags & SI_NAMED,
1415 ("Driver has goofed in cloning underways udev %jx unit %x",
1416 (uintmax_t)dev2udev(dev), dev2unit(dev)));
1420 dev_unlock_and_free();
1425 static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1426 TAILQ_HEAD_INITIALIZER(dev_ddtr);
1427 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL);
1430 destroy_dev_tq(void *ctx, int pending)
1432 struct cdev_priv *cp;
1438 while (!TAILQ_EMPTY(&dev_ddtr)) {
1439 cp = TAILQ_FIRST(&dev_ddtr);
1441 KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1442 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1443 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list);
1444 cb = cp->cdp_dtr_cb;
1445 cb_arg = cp->cdp_dtr_cb_arg;
1447 dev_unlock_and_free();
1457 * devmtx shall be locked on entry. devmtx will be unlocked after
1461 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1463 struct cdev_priv *cp;
1465 mtx_assert(&devmtx, MA_OWNED);
1466 cp = cdev2priv(dev);
1467 if (cp->cdp_flags & CDP_SCHED_DTR) {
1472 cp->cdp_flags |= CDP_SCHED_DTR;
1473 cp->cdp_dtr_cb = cb;
1474 cp->cdp_dtr_cb_arg = arg;
1475 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1477 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1482 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1486 return (destroy_dev_sched_cbl(dev, cb, arg));
1490 destroy_dev_sched(struct cdev *dev)
1493 return (destroy_dev_sched_cb(dev, NULL, NULL));
1497 destroy_dev_drain(struct cdevsw *csw)
1501 while (!LIST_EMPTY(&csw->d_devs)) {
1502 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1508 drain_dev_clone_events(void)
1511 sx_xlock(&clone_drain_lock);
1512 sx_xunlock(&clone_drain_lock);
1515 #include "opt_ddb.h"
1517 #include <sys/kernel.h>
1519 #include <ddb/ddb.h>
1521 DB_SHOW_COMMAND(cdev, db_show_cdev)
1523 struct cdev_priv *cdp;
1529 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1531 db_printf("%s %p\n", dev->si_name, dev);
1538 dev = (struct cdev *)addr;
1539 cdp = cdev2priv(dev);
1540 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n",
1541 dev->si_name, dev->si_refcount, dev->si_usecount,
1542 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first);
1543 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n",
1544 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2);
1545 flags = dev->si_flags;
1546 #define SI_FLAG(flag) do { \
1547 if (flags & (flag)) { \
1548 if (buf[0] != '\0') \
1549 strlcat(buf, ", ", sizeof(buf)); \
1550 strlcat(buf, (#flag) + 3, sizeof(buf)); \
1555 SI_FLAG(SI_ETERNAL);
1559 SI_FLAG(SI_DUMPDEV);
1560 SI_FLAG(SI_CLONELIST);
1561 db_printf("si_flags %s\n", buf);
1563 flags = cdp->cdp_flags;
1564 #define CDP_FLAG(flag) do { \
1565 if (flags & (flag)) { \
1566 if (buf[0] != '\0') \
1567 strlcat(buf, ", ", sizeof(buf)); \
1568 strlcat(buf, (#flag) + 4, sizeof(buf)); \
1573 CDP_FLAG(CDP_ACTIVE);
1574 CDP_FLAG(CDP_SCHED_DTR);
1575 db_printf("cdp_flags %s\n", buf);