2 * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
30 #include <sys/kernel.h>
31 #include <sys/systm.h>
33 #include <sys/devctl.h>
35 #include <sys/mutex.h>
36 #include <sys/module.h>
37 #include <sys/malloc.h>
39 #include <sys/vnode.h>
40 #include <sys/queue.h>
43 #include <sys/ctype.h>
44 #include <sys/ucred.h>
45 #include <sys/taskqueue.h>
46 #include <machine/stdarg.h>
48 #include <fs/devfs/devfs_int.h>
51 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage");
54 static void destroy_devl(struct cdev *dev);
55 static int destroy_dev_sched_cbl(struct cdev *dev,
56 void (*cb)(void *), void *arg);
57 static void destroy_dev_tq(void *ctx, int pending);
58 static void destroy_dev_tq_giant(void *ctx, int pending);
59 static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw,
60 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
63 static struct cdev_priv_list cdevp_free_list =
64 TAILQ_HEAD_INITIALIZER(cdevp_free_list);
65 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list =
66 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list);
76 * Free all the memory collected while the cdev mutex was
77 * locked. Since devmtx is after the system map mutex, free() cannot
78 * be called immediately and is postponed until cdev mutex can be
82 dev_unlock_and_free(void)
84 struct cdev_priv_list cdp_free;
85 struct free_cdevsw csw_free;
86 struct cdev_priv *cdp;
89 dev_lock_assert_locked();
92 * Make the local copy of the list heads while the dev_mtx is
93 * held. Free it later.
95 TAILQ_INIT(&cdp_free);
96 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list);
97 csw_free = cdevsw_gt_post_list;
98 SLIST_INIT(&cdevsw_gt_post_list);
102 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) {
103 TAILQ_REMOVE(&cdp_free, cdp, cdp_list);
104 devfs_free(&cdp->cdp_c);
106 while ((csw = SLIST_FIRST(&csw_free)) != NULL) {
107 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list);
113 dev_free_devlocked(struct cdev *cdev)
115 struct cdev_priv *cdp;
117 dev_lock_assert_locked();
118 cdp = cdev2priv(cdev);
119 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0,
120 ("destroy_dev() was not called after delist_dev(%p)", cdev));
121 KASSERT((cdp->cdp_flags & CDP_ON_ACTIVE_LIST) == 0,
122 ("%s: cdp %p (%s) on active list", __func__, cdp, cdev->si_name));
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_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,
317 .d_kqfilter = dead_kqfilter,
318 .d_mmap_single = dead_mmap_single
321 /* Default methods if driver does not specify method */
323 #define null_open (d_open_t *)nullop
324 #define null_close (d_close_t *)nullop
325 #define no_read (d_read_t *)enodev
326 #define no_write (d_write_t *)enodev
327 #define no_ioctl (d_ioctl_t *)enodev
328 #define no_mmap (d_mmap_t *)enodev
329 #define no_kqfilter (d_kqfilter_t *)enodev
330 #define no_mmap_single (d_mmap_single_t *)enodev
333 no_strategy(struct bio *bp)
336 biofinish(bp, NULL, ENODEV);
340 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
343 return (poll_no_poll(events));
347 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
352 dsw = dev_refthread(dev, &ref);
356 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
358 dev_relthread(dev, ref);
363 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
368 dsw = dev_refthread(dev, &ref);
372 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
374 dev_relthread(dev, ref);
379 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
384 dsw = dev_refthread(dev, &ref);
388 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
390 dev_relthread(dev, ref);
395 giant_strategy(struct bio *bp)
402 dsw = dev_refthread(dev, &ref);
404 biofinish(bp, NULL, ENXIO);
408 dsw->d_gianttrick->d_strategy(bp);
410 dev_relthread(dev, ref);
414 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
419 dsw = dev_refthread(dev, &ref);
423 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
425 dev_relthread(dev, ref);
430 giant_read(struct cdev *dev, struct uio *uio, int ioflag)
435 dsw = dev_refthread(dev, &ref);
439 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
441 dev_relthread(dev, ref);
446 giant_write(struct cdev *dev, struct uio *uio, int ioflag)
451 dsw = dev_refthread(dev, &ref);
455 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
457 dev_relthread(dev, ref);
462 giant_poll(struct cdev *dev, int events, struct thread *td)
467 dsw = dev_refthread(dev, &ref);
471 retval = dsw->d_gianttrick->d_poll(dev, events, td);
473 dev_relthread(dev, ref);
478 giant_kqfilter(struct cdev *dev, struct knote *kn)
483 dsw = dev_refthread(dev, &ref);
487 retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
489 dev_relthread(dev, ref);
494 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot,
495 vm_memattr_t *memattr)
500 dsw = dev_refthread(dev, &ref);
504 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot,
507 dev_relthread(dev, ref);
512 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size,
513 vm_object_t *object, int nprot)
518 dsw = dev_refthread(dev, &ref);
522 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object,
525 dev_relthread(dev, ref);
530 notify(struct cdev *dev, const char *ev, int flags)
532 static const char prefix[] = "cdev=";
538 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
539 namelen = strlen(dev->si_name);
540 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags);
543 memcpy(data, prefix, sizeof(prefix) - 1);
544 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1);
545 devctl_notify("DEVFS", "CDEV", ev, data);
550 notify_create(struct cdev *dev, int flags)
553 notify(dev, "CREATE", flags);
557 notify_destroy(struct cdev *dev)
560 notify(dev, "DESTROY", MAKEDEV_WAITOK);
564 newdev(struct make_dev_args *args, struct cdev *si)
569 dev_lock_assert_locked();
570 csw = args->mda_devsw;
572 if (csw->d_flags & D_NEEDMINOR) {
573 /* We may want to return an existing device */
574 LIST_FOREACH(si2, &csw->d_devs, si_list) {
575 if (dev2unit(si2) == args->mda_unit) {
576 dev_free_devlocked(si);
583 * If we're returning an existing device, we should make sure
584 * it isn't already initialized. This would have been caught
585 * in consumers anyways, but it's good to catch such a case
586 * early. We still need to complete initialization of the
587 * device, and we'll use whatever make_dev_args were passed in
590 KASSERT(si2 == NULL || (si2->si_flags & SI_NAMED) == 0,
591 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
592 args->mda_devsw->d_name, dev2unit(si2), devtoname(si2)));
594 si->si_drv0 = args->mda_unit;
595 si->si_drv1 = args->mda_si_drv1;
596 si->si_drv2 = args->mda_si_drv2;
597 /* Only push to csw->d_devs if it's not a cloned device. */
600 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
602 KASSERT(si->si_devsw == csw,
603 ("%s: inconsistent devsw between clone_create() and make_dev()",
610 fini_cdevsw(struct cdevsw *devsw)
614 if (devsw->d_gianttrick != NULL) {
615 gt = devsw->d_gianttrick;
616 memcpy(devsw, gt, sizeof *devsw);
617 cdevsw_free_devlocked(gt);
618 devsw->d_gianttrick = NULL;
620 devsw->d_flags &= ~D_INIT;
624 prep_cdevsw(struct cdevsw *devsw, int flags)
628 dev_lock_assert_locked();
629 if (devsw->d_flags & D_INIT)
631 if (devsw->d_flags & D_NEEDGIANT) {
633 dsw2 = malloc(sizeof *dsw2, M_DEVT,
634 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
636 if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
640 if (devsw->d_flags & D_INIT) {
642 cdevsw_free_devlocked(dsw2);
646 if (devsw->d_version != D_VERSION_04) {
648 "WARNING: Device driver \"%s\" has wrong version %s\n",
649 devsw->d_name == NULL ? "???" : devsw->d_name,
650 "and is disabled. Recompile KLD module.");
651 devsw->d_open = dead_open;
652 devsw->d_close = dead_close;
653 devsw->d_read = dead_read;
654 devsw->d_write = dead_write;
655 devsw->d_ioctl = dead_ioctl;
656 devsw->d_poll = dead_poll;
657 devsw->d_mmap = dead_mmap;
658 devsw->d_mmap_single = dead_mmap_single;
659 devsw->d_strategy = dead_strategy;
660 devsw->d_kqfilter = dead_kqfilter;
663 if ((devsw->d_flags & D_NEEDGIANT) != 0) {
664 if ((devsw->d_flags & D_GIANTOK) == 0) {
666 "WARNING: Device \"%s\" is Giant locked and may be "
667 "deleted before FreeBSD 15.0.\n",
668 devsw->d_name == NULL ? "???" : devsw->d_name);
670 if (devsw->d_gianttrick == NULL) {
671 memcpy(dsw2, devsw, sizeof *dsw2);
672 devsw->d_gianttrick = dsw2;
677 #define FIXUP(member, noop, giant) \
679 if (devsw->member == NULL) { \
680 devsw->member = noop; \
681 } else if (devsw->d_flags & D_NEEDGIANT) \
682 devsw->member = giant; \
686 FIXUP(d_open, null_open, giant_open);
687 FIXUP(d_fdopen, NULL, giant_fdopen);
688 FIXUP(d_close, null_close, giant_close);
689 FIXUP(d_read, no_read, giant_read);
690 FIXUP(d_write, no_write, giant_write);
691 FIXUP(d_ioctl, no_ioctl, giant_ioctl);
692 FIXUP(d_poll, no_poll, giant_poll);
693 FIXUP(d_mmap, no_mmap, giant_mmap);
694 FIXUP(d_strategy, no_strategy, giant_strategy);
695 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter);
696 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single);
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 dev_lock_assert_locked();
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);
950 dev_depends(struct cdev *pdev, struct cdev *cdev)
954 dev_dependsl(pdev, cdev);
959 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
960 const char *fmt, va_list ap)
965 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL"));
966 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
967 ("make_dev_alias_v: both WAITOK and NOWAIT specified"));
968 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT |
969 MAKEDEV_CHECKNAME)) == 0,
970 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags));
972 dev = devfs_alloc(flags);
976 dev->si_flags |= SI_ALIAS;
977 error = prep_devname(dev, fmt, ap);
979 if ((flags & MAKEDEV_CHECKNAME) == 0) {
980 panic("make_dev_alias_v: bad si_name "
981 "(error=%d, si_name=%s)", error, dev->si_name);
987 dev->si_flags |= SI_NAMED;
989 dev_dependsl(pdev, dev);
990 clean_unrhdrl(devfs_inos);
993 notify_create(dev, flags);
1000 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
1007 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
1010 KASSERT(res == 0 && dev != NULL,
1011 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
1016 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
1017 const char *fmt, ...)
1023 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
1029 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
1030 struct cdev *old_alias, const char *physpath)
1034 int max_parentpath_len;
1036 int devfspathbuf_len;
1042 physpath_len = strlen(physpath);
1044 if (physpath_len == 0)
1047 if (strncmp("id1,", physpath, 4) == 0) {
1050 if (physpath_len == 0)
1054 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
1055 parentpath_len = strlen(pdev->si_name);
1056 if (max_parentpath_len < parentpath_len) {
1058 printf("WARNING: Unable to alias %s "
1059 "to %s/%s - path too long\n",
1060 pdev->si_name, physpath, pdev->si_name);
1065 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
1066 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1;
1067 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags);
1068 if (devfspath == NULL) {
1073 sprintf(devfspath, "%s/%s", physpath, pdev->si_name);
1074 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) {
1075 /* Retain the existing alias. */
1080 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1083 if (old_alias != NULL)
1084 destroy_dev(old_alias);
1085 if (devfspath != NULL)
1086 free(devfspath, M_DEVBUF);
1091 destroy_devl(struct cdev *dev)
1094 struct cdev_privdata *p;
1095 struct cdev_priv *cdp;
1097 dev_lock_assert_locked();
1098 KASSERT(dev->si_flags & SI_NAMED,
1099 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
1100 KASSERT((dev->si_flags & SI_ETERNAL) == 0,
1101 ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
1104 cdp = cdev2priv(dev);
1105 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1107 * Avoid race with dev_rel(), e.g. from the populate
1108 * loop. If CDP_UNREF_DTR flag is set, the reference
1109 * to be dropped at the end of destroy_devl() was
1110 * already taken by delist_dev_locked().
1117 /* Remove name marking */
1118 dev->si_flags &= ~SI_NAMED;
1120 /* If we are a child, remove us from the parents list */
1121 if (dev->si_flags & SI_CHILD) {
1122 LIST_REMOVE(dev, si_siblings);
1123 dev->si_flags &= ~SI_CHILD;
1126 /* Kill our children */
1127 while (!LIST_EMPTY(&dev->si_children))
1128 destroy_devl(LIST_FIRST(&dev->si_children));
1130 /* Remove from clone list */
1131 if (dev->si_flags & SI_CLONELIST) {
1132 LIST_REMOVE(dev, si_clone);
1133 dev->si_flags &= ~SI_CLONELIST;
1136 mtx_lock(&cdp->cdp_threadlock);
1137 csw = dev->si_devsw;
1138 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */
1139 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
1141 mtx_unlock(&cdp->cdp_threadlock);
1142 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
1143 mtx_lock(&cdp->cdp_threadlock);
1144 if (dev->si_threadcount)
1145 printf("Still %lu threads in %s\n",
1146 dev->si_threadcount, devtoname(dev));
1148 while (dev->si_threadcount != 0) {
1149 /* Use unique dummy wait ident */
1150 mtx_unlock(&cdp->cdp_threadlock);
1151 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
1152 mtx_lock(&cdp->cdp_threadlock);
1155 mtx_unlock(&cdp->cdp_threadlock);
1157 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
1158 /* avoid out of order notify events */
1159 notify_destroy(dev);
1161 mtx_lock(&cdevpriv_mtx);
1162 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) {
1163 devfs_destroy_cdevpriv(p);
1164 mtx_lock(&cdevpriv_mtx);
1166 mtx_unlock(&cdevpriv_mtx);
1172 if (!(dev->si_flags & SI_ALIAS)) {
1173 /* Remove from cdevsw list */
1174 LIST_REMOVE(dev, si_list);
1176 /* If cdevsw has no more struct cdev *'s, clean it */
1177 if (LIST_EMPTY(&csw->d_devs)) {
1179 wakeup(&csw->d_devs);
1182 dev->si_flags &= ~SI_ALIAS;
1183 cdp->cdp_flags &= ~CDP_UNREF_DTR;
1186 if (dev->si_refcount > 0)
1187 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1189 dev_free_devlocked(dev);
1193 delist_dev_locked(struct cdev *dev)
1195 struct cdev_priv *cdp;
1198 dev_lock_assert_locked();
1199 cdp = cdev2priv(dev);
1200 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0)
1202 cdp->cdp_flags |= CDP_UNREF_DTR;
1205 LIST_FOREACH(child, &dev->si_children, si_siblings)
1206 delist_dev_locked(child);
1208 /* ensure the destroy event is queued in order */
1209 notify_destroy(dev);
1214 * This function will delist a character device and its children from
1215 * the directory listing and create a destroy event without waiting
1216 * for all character device references to go away. At some later point
1217 * destroy_dev() must be called to complete the character device
1218 * destruction. After calling this function the character device name
1219 * can instantly be re-used.
1222 delist_dev(struct cdev *dev)
1225 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev");
1227 delist_dev_locked(dev);
1232 destroy_dev(struct cdev *dev)
1235 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1238 dev_unlock_and_free();
1242 devtoname(struct cdev *dev)
1245 return (dev->si_name);
1249 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1254 if (strncmp(stem, name, i) != 0)
1256 if (!isdigit(name[i]))
1259 if (name[i] == '0' && isdigit(name[i+1]))
1261 while (isdigit(name[i])) {
1263 u += name[i++] - '0';
1276 * Helper functions for cloning device drivers.
1278 * The objective here is to make it unnecessary for the device drivers to
1279 * use rman or similar to manage their unit number space. Due to the way
1280 * we do "on-demand" devices, using rman or other "private" methods
1281 * will be very tricky to lock down properly once we lock down this file.
1283 * Instead we give the drivers these routines which puts the struct cdev *'s
1284 * that are to be managed on their own list, and gives the driver the ability
1285 * to ask for the first free unit number or a given specified unit number.
1287 * In addition these routines support paired devices (pty, nmdm and similar)
1288 * by respecting a number of "flag" bits in the minor number.
1293 LIST_HEAD(,cdev) head;
1297 clone_setup(struct clonedevs **cdp)
1300 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1301 LIST_INIT(&(*cdp)->head);
1305 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1306 struct cdev **dp, int extra)
1308 struct clonedevs *cd;
1309 struct cdev *dev, *ndev, *dl, *de;
1310 struct make_dev_args args;
1313 KASSERT(*cdp != NULL,
1314 ("clone_setup() not called in driver \"%s\"", csw->d_name));
1315 KASSERT(!(extra & CLONE_UNITMASK),
1316 ("Illegal extra bits (0x%x) in clone_create", extra));
1317 KASSERT(*up <= CLONE_UNITMASK,
1318 ("Too high unit (0x%x) in clone_create", *up));
1319 KASSERT(csw->d_flags & D_NEEDMINOR,
1320 ("clone_create() on cdevsw without minor numbers"));
1323 * Search the list for a lot of things in one go:
1324 * A preexisting match is returned immediately.
1325 * The lowest free unit number if we are passed -1, and the place
1326 * in the list where we should insert that new element.
1327 * The place to insert a specified unit number, if applicable
1328 * the end of the list.
1331 ndev = devfs_alloc(MAKEDEV_WAITOK);
1333 prep_cdevsw(csw, MAKEDEV_WAITOK);
1337 LIST_FOREACH(dev, &cd->head, si_clone) {
1338 KASSERT(dev->si_flags & SI_CLONELIST,
1339 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1341 if (u == (unit | extra)) {
1347 if (unit == -1 && u == low) {
1351 } else if (u < (unit | extra)) {
1354 } else if (u > (unit | extra)) {
1360 unit = low & CLONE_UNITMASK;
1361 make_dev_args_init(&args);
1362 args.mda_unit = unit | extra;
1363 args.mda_devsw = csw;
1364 dev = newdev(&args, ndev);
1365 if (dev->si_flags & SI_CLONELIST) {
1366 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1367 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1368 LIST_FOREACH(dev, &cd->head, si_clone) {
1369 printf("\t%p %s\n", dev, dev->si_name);
1373 KASSERT(!(dev->si_flags & SI_CLONELIST),
1374 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1376 LIST_INSERT_BEFORE(dl, dev, si_clone);
1377 else if (de != NULL)
1378 LIST_INSERT_AFTER(de, dev, si_clone);
1380 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1381 dev->si_flags |= SI_CLONELIST;
1383 dev_unlock_and_free();
1388 * Kill everything still on the list. The driver should already have
1389 * disposed of any softc hung of the struct cdev *'s at this time.
1392 clone_cleanup(struct clonedevs **cdp)
1395 struct cdev_priv *cp;
1396 struct clonedevs *cd;
1402 while (!LIST_EMPTY(&cd->head)) {
1403 dev = LIST_FIRST(&cd->head);
1404 LIST_REMOVE(dev, si_clone);
1405 KASSERT(dev->si_flags & SI_CLONELIST,
1406 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1407 dev->si_flags &= ~SI_CLONELIST;
1408 cp = cdev2priv(dev);
1409 if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1410 cp->cdp_flags |= CDP_SCHED_DTR;
1411 KASSERT(dev->si_flags & SI_NAMED,
1412 ("Driver has goofed in cloning underways udev %jx unit %x",
1413 (uintmax_t)dev2udev(dev), dev2unit(dev)));
1417 dev_unlock_and_free();
1422 static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1423 TAILQ_HEAD_INITIALIZER(dev_ddtr);
1424 static TAILQ_HEAD(, cdev_priv) dev_ddtr_giant =
1425 TAILQ_HEAD_INITIALIZER(dev_ddtr_giant);
1426 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, &dev_ddtr);
1427 static struct task dev_dtr_task_giant = TASK_INITIALIZER(0, destroy_dev_tq_giant,
1431 destroy_dev_tq(void *ctx, int pending)
1433 TAILQ_HEAD(, cdev_priv) *ddtr = ctx;
1434 struct cdev_priv *cp;
1440 while (!TAILQ_EMPTY(ddtr)) {
1441 cp = TAILQ_FIRST(ddtr);
1443 KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1444 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1445 TAILQ_REMOVE(ddtr, cp, cdp_dtr_list);
1446 cb = cp->cdp_dtr_cb;
1447 cb_arg = cp->cdp_dtr_cb_arg;
1449 dev_unlock_and_free();
1459 destroy_dev_tq_giant(void *ctx, int pending)
1462 destroy_dev_tq(ctx, pending);
1467 * devmtx shall be locked on entry. devmtx will be unlocked after
1471 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1473 struct cdev_priv *cp;
1476 dev_lock_assert_locked();
1477 cp = cdev2priv(dev);
1478 if (cp->cdp_flags & CDP_SCHED_DTR) {
1483 cp->cdp_flags |= CDP_SCHED_DTR;
1484 cp->cdp_dtr_cb = cb;
1485 cp->cdp_dtr_cb_arg = arg;
1486 need_giant = (dev->si_devsw->d_flags & D_NEEDGIANT) != 0;
1488 TAILQ_INSERT_TAIL(&dev_ddtr_giant, cp, cdp_dtr_list);
1490 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1493 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task_giant);
1495 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task);
1500 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1504 return (destroy_dev_sched_cbl(dev, cb, arg));
1508 destroy_dev_sched(struct cdev *dev)
1511 return (destroy_dev_sched_cb(dev, NULL, NULL));
1515 destroy_dev_drain(struct cdevsw *csw)
1519 while (!LIST_EMPTY(&csw->d_devs)) {
1520 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1525 #include "opt_ddb.h"
1527 #include <sys/kernel.h>
1529 #include <ddb/ddb.h>
1531 DB_SHOW_COMMAND(cdev, db_show_cdev)
1533 struct cdev_priv *cdp;
1539 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1541 db_printf("%s %p\n", dev->si_name, dev);
1548 dev = (struct cdev *)addr;
1549 cdp = cdev2priv(dev);
1550 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n",
1551 dev->si_name, dev->si_refcount, dev->si_usecount,
1552 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first);
1553 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n",
1554 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2);
1555 flags = dev->si_flags;
1556 #define SI_FLAG(flag) do { \
1557 if (flags & (flag)) { \
1558 if (buf[0] != '\0') \
1559 strlcat(buf, ", ", sizeof(buf)); \
1560 strlcat(buf, (#flag) + 3, sizeof(buf)); \
1565 SI_FLAG(SI_ETERNAL);
1569 SI_FLAG(SI_DUMPDEV);
1570 SI_FLAG(SI_CLONELIST);
1571 db_printf("si_flags %s\n", buf);
1573 flags = cdp->cdp_flags;
1574 #define CDP_FLAG(flag) do { \
1575 if (flags & (flag)) { \
1576 if (buf[0] != '\0') \
1577 strlcat(buf, ", ", sizeof(buf)); \
1578 strlcat(buf, (#flag) + 4, sizeof(buf)); \
1583 CDP_FLAG(CDP_ACTIVE);
1584 CDP_FLAG(CDP_SCHED_DTR);
1585 db_printf("cdp_flags %s\n", buf);