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>
36 #include <sys/devctl.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 dev_lock_assert_locked();
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 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);
127 cdevsw_free_devlocked(struct cdevsw *csw)
130 dev_lock_assert_locked();
131 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
142 dev_ref(struct cdev *dev)
145 dev_lock_assert_unlocked();
152 dev_refl(struct cdev *dev)
155 dev_lock_assert_locked();
160 dev_rel(struct cdev *dev)
164 dev_lock_assert_unlocked();
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 dev_lock_assert_unlocked();
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);
205 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref)
208 struct cdev_priv *cdp;
211 dev_lock_assert_unlocked();
212 if ((vp->v_vflag & VV_ETERNALDEV) != 0) {
216 KASSERT((dev->si_flags & SI_ETERNAL) != 0,
217 ("Not eternal cdev"));
220 KASSERT(csw != NULL, ("Eternal cdev is destroyed"));
232 cdp = cdev2priv(dev);
233 mtx_lock(&cdp->cdp_threadlock);
234 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
237 atomic_add_long(&dev->si_threadcount, 1);
239 mtx_unlock(&cdp->cdp_threadlock);
249 dev_relthread(struct cdev *dev, int ref)
252 dev_lock_assert_unlocked();
255 KASSERT(dev->si_threadcount > 0,
256 ("%s threadcount is wrong", dev->si_name));
257 atomic_subtract_rel_long(&dev->si_threadcount, 1);
286 /* Define a dead_cdevsw for use when devices leave unexpectedly. */
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
297 dead_strategy(struct bio *bp)
300 biofinish(bp, NULL, ENXIO);
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
307 static struct cdevsw dead_cdevsw = {
308 .d_version = D_VERSION,
310 .d_close = dead_close,
312 .d_write = dead_write,
313 .d_ioctl = dead_ioctl,
316 .d_strategy = dead_strategy,
319 .d_kqfilter = dead_kqfilter,
320 .d_mmap_single = dead_mmap_single
323 /* Default methods if driver does not specify method */
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
335 no_strategy(struct bio *bp)
338 biofinish(bp, NULL, ENODEV);
342 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
345 return (poll_no_poll(events));
348 #define no_dump (dumper_t *)enodev
351 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
356 dsw = dev_refthread(dev, &ref);
360 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
362 dev_relthread(dev, ref);
367 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
372 dsw = dev_refthread(dev, &ref);
376 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
378 dev_relthread(dev, ref);
383 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
388 dsw = dev_refthread(dev, &ref);
392 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
394 dev_relthread(dev, ref);
399 giant_strategy(struct bio *bp)
406 dsw = dev_refthread(dev, &ref);
408 biofinish(bp, NULL, ENXIO);
412 dsw->d_gianttrick->d_strategy(bp);
414 dev_relthread(dev, ref);
418 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
423 dsw = dev_refthread(dev, &ref);
427 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
429 dev_relthread(dev, ref);
434 giant_read(struct cdev *dev, struct uio *uio, int ioflag)
439 dsw = dev_refthread(dev, &ref);
443 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
445 dev_relthread(dev, ref);
450 giant_write(struct cdev *dev, struct uio *uio, int ioflag)
455 dsw = dev_refthread(dev, &ref);
459 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
461 dev_relthread(dev, ref);
466 giant_poll(struct cdev *dev, int events, struct thread *td)
471 dsw = dev_refthread(dev, &ref);
475 retval = dsw->d_gianttrick->d_poll(dev, events, td);
477 dev_relthread(dev, ref);
482 giant_kqfilter(struct cdev *dev, struct knote *kn)
487 dsw = dev_refthread(dev, &ref);
491 retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
493 dev_relthread(dev, ref);
498 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot,
499 vm_memattr_t *memattr)
504 dsw = dev_refthread(dev, &ref);
508 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot,
511 dev_relthread(dev, ref);
516 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size,
517 vm_object_t *object, int nprot)
522 dsw = dev_refthread(dev, &ref);
526 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object,
529 dev_relthread(dev, ref);
534 notify(struct cdev *dev, const char *ev, int flags)
536 static const char prefix[] = "cdev=";
542 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
543 namelen = strlen(dev->si_name);
544 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags);
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);
554 notify_create(struct cdev *dev, int flags)
557 notify(dev, "CREATE", flags);
561 notify_destroy(struct cdev *dev)
564 notify(dev, "DESTROY", MAKEDEV_WAITOK);
568 newdev(struct make_dev_args *args, struct cdev *si)
573 dev_lock_assert_locked();
574 csw = args->mda_devsw;
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);
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
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)));
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. */
604 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
606 KASSERT(si->si_devsw == csw,
607 ("%s: inconsistent devsw between clone_create() and make_dev()",
614 fini_cdevsw(struct cdevsw *devsw)
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;
624 devsw->d_flags &= ~D_INIT;
628 prep_cdevsw(struct cdevsw *devsw, int flags)
632 dev_lock_assert_locked();
633 if (devsw->d_flags & D_INIT)
635 if (devsw->d_flags & D_NEEDGIANT) {
637 dsw2 = malloc(sizeof *dsw2, M_DEVT,
638 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
640 if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
644 if (devsw->d_flags & D_INIT) {
646 cdevsw_free_devlocked(dsw2);
650 if (devsw->d_version != D_VERSION_04) {
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;
668 if ((devsw->d_flags & D_NEEDGIANT) != 0) {
669 if ((devsw->d_flags & D_GIANTOK) == 0) {
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);
675 if (devsw->d_gianttrick == NULL) {
676 memcpy(dsw2, devsw, sizeof *dsw2);
677 devsw->d_gianttrick = dsw2;
682 #define FIXUP(member, noop, giant) \
684 if (devsw->member == NULL) { \
685 devsw->member = noop; \
686 } else if (devsw->d_flags & D_NEEDGIANT) \
687 devsw->member = giant; \
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);
703 if (devsw->d_dump == NULL) devsw->d_dump = no_dump;
705 LIST_INIT(&devsw->d_devs);
707 devsw->d_flags |= D_INIT;
710 cdevsw_free_devlocked(dsw2);
715 prep_devname(struct cdev *dev, const char *fmt, va_list ap)
718 char *from, *q, *s, *to;
720 dev_lock_assert_locked();
722 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap);
723 if (len > sizeof(dev->si_name) - 1)
724 return (ENAMETOOLONG);
726 /* Strip leading slashes. */
727 for (from = dev->si_name; *from == '/'; from++)
730 for (to = dev->si_name; *from != '\0'; from++, to++) {
732 * Spaces and double quotation marks cause
733 * problems for the devctl(4) protocol.
734 * Reject names containing those characters.
736 if (isspace(*from) || *from == '"')
738 /* Treat multiple sequential slashes as single. */
739 while (from[0] == '/' && from[1] == '/')
741 /* Trailing slash is considered invalid. */
742 if (from[0] == '/' && from[1] == '\0')
748 if (dev->si_name[0] == '\0')
751 /* Disallow "." and ".." components. */
752 for (s = dev->si_name;;) {
753 for (q = s; *q != '/' && *q != '\0'; q++)
755 if (q - s == 1 && s[0] == '.')
757 if (q - s == 2 && s[0] == '.' && s[1] == '.')
764 if (devfs_dev_exists(dev->si_name) != 0)
771 make_dev_args_init_impl(struct make_dev_args *args, size_t sz)
779 make_dev_sv(struct make_dev_args *args1, struct cdev **dres,
780 const char *fmt, va_list ap)
782 struct cdev *dev, *dev_new;
783 struct make_dev_args args;
786 bzero(&args, sizeof(args));
787 if (sizeof(args) < args1->mda_size)
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);
797 res = prep_cdevsw(args.mda_devsw, args.mda_flags);
803 dev = newdev(&args, dev_new);
804 if ((dev->si_flags & SI_NAMED) == 0) {
805 res = prep_devname(dev, fmt, ap);
807 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) {
809 "make_dev_sv: bad si_name (error=%d, si_name=%s)",
812 if (dev == dev_new) {
813 LIST_REMOVE(dev, si_list);
821 if ((args.mda_flags & MAKEDEV_REF) != 0)
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;
836 clean_unrhdrl(devfs_inos);
837 dev_unlock_and_free();
839 notify_create(dev, args.mda_flags);
846 make_dev_s(struct make_dev_args *args, struct cdev **dres,
847 const char *fmt, ...)
853 res = make_dev_sv(args, dres, fmt, ap);
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,
863 struct make_dev_args args;
865 make_dev_args_init(&args);
866 args.mda_flags = flags;
867 args.mda_devsw = devsw;
871 args.mda_mode = mode;
872 args.mda_unit = unit;
873 return (make_dev_sv(&args, dres, fmt, ap));
877 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
878 const char *fmt, ...)
885 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
888 KASSERT(res == 0 && dev != NULL,
889 ("make_dev: failed make_dev_credv (error=%d)", res));
894 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
895 gid_t gid, int mode, const char *fmt, ...)
902 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
905 KASSERT(res == 0 && dev != NULL,
906 ("make_dev_cred: failed make_dev_credv (error=%d)", res));
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, ...)
919 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
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);
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, ...)
937 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
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));
948 dev_dependsl(struct cdev *pdev, struct cdev *cdev)
951 cdev->si_parent = pdev;
952 cdev->si_flags |= SI_CHILD;
953 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
957 dev_depends(struct cdev *pdev, struct cdev *cdev)
961 dev_dependsl(pdev, cdev);
966 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
967 const char *fmt, va_list ap)
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));
979 dev = devfs_alloc(flags);
983 dev->si_flags |= SI_ALIAS;
984 error = prep_devname(dev, fmt, ap);
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);
994 dev->si_flags |= SI_NAMED;
996 dev_dependsl(pdev, dev);
997 clean_unrhdrl(devfs_inos);
1000 notify_create(dev, flags);
1007 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
1014 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
1017 KASSERT(res == 0 && dev != NULL,
1018 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
1023 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
1024 const char *fmt, ...)
1030 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
1036 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
1037 struct cdev *old_alias, const char *physpath)
1041 int max_parentpath_len;
1043 int devfspathbuf_len;
1049 physpath_len = strlen(physpath);
1051 if (physpath_len == 0)
1054 if (strncmp("id1,", physpath, 4) == 0) {
1057 if (physpath_len == 0)
1061 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
1062 parentpath_len = strlen(pdev->si_name);
1063 if (max_parentpath_len < parentpath_len) {
1065 printf("WARNING: Unable to alias %s "
1066 "to %s/%s - path too long\n",
1067 pdev->si_name, physpath, pdev->si_name);
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) {
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. */
1087 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1090 if (old_alias != NULL)
1091 destroy_dev(old_alias);
1092 if (devfspath != NULL)
1093 free(devfspath, M_DEVBUF);
1098 destroy_devl(struct cdev *dev)
1101 struct cdev_privdata *p;
1102 struct cdev_priv *cdp;
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",
1111 cdp = cdev2priv(dev);
1112 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
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().
1124 /* Remove name marking */
1125 dev->si_flags &= ~SI_NAMED;
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;
1133 /* Kill our children */
1134 while (!LIST_EMPTY(&dev->si_children))
1135 destroy_devl(LIST_FIRST(&dev->si_children));
1137 /* Remove from clone list */
1138 if (dev->si_flags & SI_CLONELIST) {
1139 LIST_REMOVE(dev, si_clone);
1140 dev->si_flags &= ~SI_CLONELIST;
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) {
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));
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);
1162 mtx_unlock(&cdp->cdp_threadlock);
1164 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1165 /* avoid out of order notify events */
1166 notify_destroy(dev);
1168 mtx_lock(&cdevpriv_mtx);
1169 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) {
1170 devfs_destroy_cdevpriv(p);
1171 mtx_lock(&cdevpriv_mtx);
1173 mtx_unlock(&cdevpriv_mtx);
1179 if (!(dev->si_flags & SI_ALIAS)) {
1180 /* Remove from cdevsw list */
1181 LIST_REMOVE(dev, si_list);
1183 /* If cdevsw has no more struct cdev *'s, clean it */
1184 if (LIST_EMPTY(&csw->d_devs)) {
1186 wakeup(&csw->d_devs);
1189 dev->si_flags &= ~SI_ALIAS;
1190 cdp->cdp_flags &= ~CDP_UNREF_DTR;
1193 if (dev->si_refcount > 0)
1194 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1196 dev_free_devlocked(dev);
1200 delist_dev_locked(struct cdev *dev)
1202 struct cdev_priv *cdp;
1205 dev_lock_assert_locked();
1206 cdp = cdev2priv(dev);
1207 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0)
1209 cdp->cdp_flags |= CDP_UNREF_DTR;
1212 LIST_FOREACH(child, &dev->si_children, si_siblings)
1213 delist_dev_locked(child);
1215 /* ensure the destroy event is queued in order */
1216 notify_destroy(dev);
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.
1229 delist_dev(struct cdev *dev)
1232 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev");
1234 delist_dev_locked(dev);
1239 destroy_dev(struct cdev *dev)
1242 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1245 dev_unlock_and_free();
1249 devtoname(struct cdev *dev)
1252 return (dev->si_name);
1256 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1261 if (strncmp(stem, name, i) != 0)
1263 if (!isdigit(name[i]))
1266 if (name[i] == '0' && isdigit(name[i+1]))
1268 while (isdigit(name[i])) {
1270 u += name[i++] - '0';
1283 * Helper functions for cloning device drivers.
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.
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.
1294 * In addition these routines support paired devices (pty, nmdm and similar)
1295 * by respecting a number of "flag" bits in the minor number.
1300 LIST_HEAD(,cdev) head;
1304 clone_setup(struct clonedevs **cdp)
1307 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1308 LIST_INIT(&(*cdp)->head);
1312 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1313 struct cdev **dp, int extra)
1315 struct clonedevs *cd;
1316 struct cdev *dev, *ndev, *dl, *de;
1317 struct make_dev_args args;
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"));
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.
1338 ndev = devfs_alloc(MAKEDEV_WAITOK);
1340 prep_cdevsw(csw, MAKEDEV_WAITOK);
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));
1348 if (u == (unit | extra)) {
1354 if (unit == -1 && u == low) {
1358 } else if (u < (unit | extra)) {
1361 } else if (u > (unit | extra)) {
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);
1380 KASSERT(!(dev->si_flags & SI_CLONELIST),
1381 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1383 LIST_INSERT_BEFORE(dl, dev, si_clone);
1384 else if (de != NULL)
1385 LIST_INSERT_AFTER(de, dev, si_clone);
1387 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1388 dev->si_flags |= SI_CLONELIST;
1390 dev_unlock_and_free();
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.
1399 clone_cleanup(struct clonedevs **cdp)
1402 struct cdev_priv *cp;
1403 struct clonedevs *cd;
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)));
1424 dev_unlock_and_free();
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);
1434 destroy_dev_tq(void *ctx, int pending)
1436 struct cdev_priv *cp;
1442 while (!TAILQ_EMPTY(&dev_ddtr)) {
1443 cp = TAILQ_FIRST(&dev_ddtr);
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;
1451 dev_unlock_and_free();
1461 * devmtx shall be locked on entry. devmtx will be unlocked after
1465 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1467 struct cdev_priv *cp;
1469 dev_lock_assert_locked();
1470 cp = cdev2priv(dev);
1471 if (cp->cdp_flags & CDP_SCHED_DTR) {
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);
1481 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1486 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1490 return (destroy_dev_sched_cbl(dev, cb, arg));
1494 destroy_dev_sched(struct cdev *dev)
1497 return (destroy_dev_sched_cb(dev, NULL, NULL));
1501 destroy_dev_drain(struct cdevsw *csw)
1505 while (!LIST_EMPTY(&csw->d_devs)) {
1506 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1512 drain_dev_clone_events(void)
1515 sx_xlock(&clone_drain_lock);
1516 sx_xunlock(&clone_drain_lock);
1519 #include "opt_ddb.h"
1521 #include <sys/kernel.h>
1523 #include <ddb/ddb.h>
1525 DB_SHOW_COMMAND(cdev, db_show_cdev)
1527 struct cdev_priv *cdp;
1533 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1535 db_printf("%s %p\n", dev->si_name, dev);
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)); \
1559 SI_FLAG(SI_ETERNAL);
1563 SI_FLAG(SI_DUMPDEV);
1564 SI_FLAG(SI_CLONELIST);
1565 db_printf("si_flags %s\n", buf);
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)); \
1577 CDP_FLAG(CDP_ACTIVE);
1578 CDP_FLAG(CDP_SCHED_DTR);
1579 db_printf("cdp_flags %s\n", buf);