2 * Copyright (c) 1999-2002 Poul-Henning Kamp
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/systm.h>
36 #include <sys/mutex.h>
37 #include <sys/module.h>
38 #include <sys/malloc.h>
40 #include <sys/vnode.h>
41 #include <sys/queue.h>
44 #include <sys/ctype.h>
45 #include <sys/ucred.h>
46 #include <sys/taskqueue.h>
47 #include <machine/stdarg.h>
49 #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 struct cdev *make_dev_credv(int flags,
58 struct cdevsw *devsw, int unit,
59 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
62 static struct cdev_priv_list cdevp_free_list =
63 TAILQ_HEAD_INITIALIZER(cdevp_free_list);
64 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list =
65 SLIST_HEAD_INITIALIZER();
75 * Free all the memory collected while the cdev mutex was
76 * locked. Since devmtx is after the system map mutex, free() cannot
77 * be called immediately and is postponed until cdev mutex can be
81 dev_unlock_and_free(void)
83 struct cdev_priv_list cdp_free;
84 struct free_cdevsw csw_free;
85 struct cdev_priv *cdp;
88 mtx_assert(&devmtx, MA_OWNED);
91 * Make the local copy of the list heads while the dev_mtx is
92 * held. Free it later.
94 TAILQ_INIT(&cdp_free);
95 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list);
96 csw_free = cdevsw_gt_post_list;
97 SLIST_INIT(&cdevsw_gt_post_list);
101 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) {
102 TAILQ_REMOVE(&cdp_free, cdp, cdp_list);
103 devfs_free(&cdp->cdp_c);
105 while ((csw = SLIST_FIRST(&csw_free)) != NULL) {
106 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list);
112 dev_free_devlocked(struct cdev *cdev)
114 struct cdev_priv *cdp;
116 mtx_assert(&devmtx, MA_OWNED);
117 cdp = cdev2priv(cdev);
118 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list);
122 cdevsw_free_devlocked(struct cdevsw *csw)
125 mtx_assert(&devmtx, MA_OWNED);
126 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
137 dev_ref(struct cdev *dev)
140 mtx_assert(&devmtx, MA_NOTOWNED);
147 dev_refl(struct cdev *dev)
150 mtx_assert(&devmtx, MA_OWNED);
155 dev_rel(struct cdev *dev)
159 mtx_assert(&devmtx, MA_NOTOWNED);
162 KASSERT(dev->si_refcount >= 0,
163 ("dev_rel(%s) gave negative count", devtoname(dev)));
165 if (dev->si_usecount == 0 &&
166 (dev->si_flags & SI_CHEAPCLONE) && (dev->si_flags & SI_NAMED))
170 if (dev->si_devsw == NULL && dev->si_refcount == 0) {
171 LIST_REMOVE(dev, si_list);
180 dev_refthread(struct cdev *dev)
183 struct cdev_priv *cdp;
185 mtx_assert(&devmtx, MA_NOTOWNED);
189 cdp = cdev2priv(dev);
190 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0)
191 dev->si_threadcount++;
200 devvn_refthread(struct vnode *vp, struct cdev **devp)
203 struct cdev_priv *cdp;
205 mtx_assert(&devmtx, MA_NOTOWNED);
210 cdp = cdev2priv(*devp);
211 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
212 csw = (*devp)->si_devsw;
214 (*devp)->si_threadcount++;
222 dev_relthread(struct cdev *dev)
225 mtx_assert(&devmtx, MA_NOTOWNED);
227 KASSERT(dev->si_threadcount > 0,
228 ("%s threadcount is wrong", dev->si_name));
229 dev->si_threadcount--;
259 /* Define a dead_cdevsw for use when devices leave unexpectedly. */
261 #define dead_open (d_open_t *)enxio
262 #define dead_close (d_close_t *)enxio
263 #define dead_read (d_read_t *)enxio
264 #define dead_write (d_write_t *)enxio
265 #define dead_ioctl (d_ioctl_t *)enxio
266 #define dead_poll (d_poll_t *)enodev
267 #define dead_mmap (d_mmap_t *)enodev
270 dead_strategy(struct bio *bp)
273 biofinish(bp, NULL, ENXIO);
276 #define dead_dump (dumper_t *)enxio
277 #define dead_kqfilter (d_kqfilter_t *)enxio
279 static struct cdevsw dead_cdevsw = {
280 .d_version = D_VERSION,
281 .d_flags = D_NEEDGIANT, /* XXX: does dead_strategy need this ? */
283 .d_close = dead_close,
285 .d_write = dead_write,
286 .d_ioctl = dead_ioctl,
289 .d_strategy = dead_strategy,
292 .d_kqfilter = dead_kqfilter
295 /* Default methods if driver does not specify method */
297 #define null_open (d_open_t *)nullop
298 #define null_close (d_close_t *)nullop
299 #define no_read (d_read_t *)enodev
300 #define no_write (d_write_t *)enodev
301 #define no_ioctl (d_ioctl_t *)enodev
302 #define no_mmap (d_mmap_t *)enodev
303 #define no_kqfilter (d_kqfilter_t *)enodev
306 no_strategy(struct bio *bp)
309 biofinish(bp, NULL, ENODEV);
313 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused)
316 * Return true for read/write. If the user asked for something
317 * special, return POLLNVAL, so that clients have a way of
318 * determining reliably whether or not the extended
319 * functionality is present without hard-coding knowledge
320 * of specific filesystem implementations.
321 * Stay in sync with vop_nopoll().
323 if (events & ~POLLSTANDARD)
326 return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
329 #define no_dump (dumper_t *)enodev
332 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
337 dsw = dev_refthread(dev);
341 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td);
348 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp)
353 dsw = dev_refthread(dev);
357 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp);
364 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
369 dsw = dev_refthread(dev);
373 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td);
380 giant_strategy(struct bio *bp)
386 dsw = dev_refthread(dev);
388 biofinish(bp, NULL, ENXIO);
392 dsw->d_gianttrick->d_strategy(bp);
398 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
403 dsw = dev_refthread(dev);
407 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td);
414 giant_read(struct cdev *dev, struct uio *uio, int ioflag)
419 dsw = dev_refthread(dev);
423 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag);
430 giant_write(struct cdev *dev, struct uio *uio, int ioflag)
435 dsw = dev_refthread(dev);
439 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag);
446 giant_poll(struct cdev *dev, int events, struct thread *td)
451 dsw = dev_refthread(dev);
455 retval = dsw->d_gianttrick->d_poll(dev, events, td);
462 giant_kqfilter(struct cdev *dev, struct knote *kn)
467 dsw = dev_refthread(dev);
471 retval = dsw->d_gianttrick->d_kqfilter(dev, kn);
478 giant_mmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int nprot)
483 dsw = dev_refthread(dev);
487 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot);
495 notify(struct cdev *dev, const char *ev)
497 static const char prefix[] = "cdev=";
503 namelen = strlen(dev->si_name);
504 data = malloc(namelen + sizeof(prefix), M_TEMP, M_WAITOK);
505 memcpy(data, prefix, sizeof(prefix) - 1);
506 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1);
507 devctl_notify("DEVFS", "CDEV", ev, data);
512 notify_create(struct cdev *dev)
515 notify(dev, "CREATE");
519 notify_destroy(struct cdev *dev)
522 notify(dev, "DESTROY");
526 newdev(struct cdevsw *csw, int y, struct cdev *si)
531 mtx_assert(&devmtx, MA_OWNED);
533 if (csw->d_flags & D_NEEDMINOR) {
534 /* We may want to return an existing device */
535 LIST_FOREACH(si2, &csw->d_devs, si_list) {
536 if (si2->si_drv0 == udev) {
537 dev_free_devlocked(si);
544 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
549 fini_cdevsw(struct cdevsw *devsw)
553 if (devsw->d_gianttrick != NULL) {
554 gt = devsw->d_gianttrick;
555 memcpy(devsw, gt, sizeof *devsw);
556 cdevsw_free_devlocked(gt);
557 devsw->d_gianttrick = NULL;
559 devsw->d_flags &= ~D_INIT;
563 prep_cdevsw(struct cdevsw *devsw)
567 mtx_assert(&devmtx, MA_OWNED);
568 if (devsw->d_flags & D_INIT)
570 if (devsw->d_flags & D_NEEDGIANT) {
572 dsw2 = malloc(sizeof *dsw2, M_DEVT, M_WAITOK);
576 if (devsw->d_flags & D_INIT) {
578 cdevsw_free_devlocked(dsw2);
582 if (devsw->d_version != D_VERSION_01) {
584 "WARNING: Device driver \"%s\" has wrong version %s\n",
585 devsw->d_name == NULL ? "???" : devsw->d_name,
586 "and is disabled. Recompile KLD module.");
587 devsw->d_open = dead_open;
588 devsw->d_close = dead_close;
589 devsw->d_read = dead_read;
590 devsw->d_write = dead_write;
591 devsw->d_ioctl = dead_ioctl;
592 devsw->d_poll = dead_poll;
593 devsw->d_mmap = dead_mmap;
594 devsw->d_strategy = dead_strategy;
595 devsw->d_dump = dead_dump;
596 devsw->d_kqfilter = dead_kqfilter;
599 if (devsw->d_flags & D_NEEDGIANT) {
600 if (devsw->d_gianttrick == NULL) {
601 memcpy(dsw2, devsw, sizeof *dsw2);
602 devsw->d_gianttrick = dsw2;
607 #define FIXUP(member, noop, giant) \
609 if (devsw->member == NULL) { \
610 devsw->member = noop; \
611 } else if (devsw->d_flags & D_NEEDGIANT) \
612 devsw->member = giant; \
616 FIXUP(d_open, null_open, giant_open);
617 FIXUP(d_fdopen, NULL, giant_fdopen);
618 FIXUP(d_close, null_close, giant_close);
619 FIXUP(d_read, no_read, giant_read);
620 FIXUP(d_write, no_write, giant_write);
621 FIXUP(d_ioctl, no_ioctl, giant_ioctl);
622 FIXUP(d_poll, no_poll, giant_poll);
623 FIXUP(d_mmap, no_mmap, giant_mmap);
624 FIXUP(d_strategy, no_strategy, giant_strategy);
625 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter);
627 if (devsw->d_dump == NULL) devsw->d_dump = no_dump;
629 LIST_INIT(&devsw->d_devs);
631 devsw->d_flags |= D_INIT;
634 cdevsw_free_devlocked(dsw2);
638 make_dev_credv(int flags, struct cdevsw *devsw, int unit,
639 struct ucred *cr, uid_t uid,
640 gid_t gid, int mode, const char *fmt, va_list ap)
648 dev = newdev(devsw, unit, dev);
649 if (flags & MAKEDEV_REF)
651 if (dev->si_flags & SI_CHEAPCLONE &&
652 dev->si_flags & SI_NAMED) {
654 * This is allowed as it removes races and generally
655 * simplifies cloning devices.
658 dev_unlock_and_free();
661 KASSERT(!(dev->si_flags & SI_NAMED),
662 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
663 devsw->d_name, dev2unit(dev), devtoname(dev)));
665 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap);
666 if (i > (sizeof dev->__si_namebuf - 1)) {
667 printf("WARNING: Device name truncated! (%s)\n",
671 dev->si_flags |= SI_NAMED;
673 dev->si_cred = crhold(cr);
681 clean_unrhdrl(devfs_inos);
682 dev_unlock_and_free();
690 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
691 const char *fmt, ...)
697 dev = make_dev_credv(0, devsw, unit, NULL, uid, gid, mode, fmt, ap);
703 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
704 gid_t gid, int mode, const char *fmt, ...)
710 dev = make_dev_credv(0, devsw, unit, cr, uid, gid, mode, fmt, ap);
717 make_dev_credf(int flags, struct cdevsw *devsw, int unit,
718 struct ucred *cr, uid_t uid,
719 gid_t gid, int mode, const char *fmt, ...)
725 dev = make_dev_credv(flags, devsw, unit, cr, uid, gid, mode,
733 dev_dependsl(struct cdev *pdev, struct cdev *cdev)
736 cdev->si_parent = pdev;
737 cdev->si_flags |= SI_CHILD;
738 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
743 dev_depends(struct cdev *pdev, struct cdev *cdev)
747 dev_dependsl(pdev, cdev);
752 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
758 KASSERT(pdev != NULL, ("NULL pdev"));
761 dev->si_flags |= SI_ALIAS;
762 dev->si_flags |= SI_NAMED;
764 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap);
765 if (i > (sizeof dev->__si_namebuf - 1)) {
766 printf("WARNING: Device name truncated! (%s)\n",
772 dev_dependsl(pdev, dev);
773 clean_unrhdrl(devfs_inos);
782 destroy_devl(struct cdev *dev)
785 struct cdev_privdata *p, *p1;
787 mtx_assert(&devmtx, MA_OWNED);
788 KASSERT(dev->si_flags & SI_NAMED,
789 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
793 /* Remove name marking */
794 dev->si_flags &= ~SI_NAMED;
796 /* If we are a child, remove us from the parents list */
797 if (dev->si_flags & SI_CHILD) {
798 LIST_REMOVE(dev, si_siblings);
799 dev->si_flags &= ~SI_CHILD;
802 /* Kill our children */
803 while (!LIST_EMPTY(&dev->si_children))
804 destroy_devl(LIST_FIRST(&dev->si_children));
806 /* Remove from clone list */
807 if (dev->si_flags & SI_CLONELIST) {
808 LIST_REMOVE(dev, si_clone);
809 dev->si_flags &= ~SI_CLONELIST;
812 dev->si_refcount++; /* Avoid race with dev_rel() */
814 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */
815 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
817 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
818 if (dev->si_threadcount)
819 printf("Still %lu threads in %s\n",
820 dev->si_threadcount, devtoname(dev));
822 while (dev->si_threadcount != 0) {
823 /* Use unique dummy wait ident */
824 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
829 mtx_lock(&cdevpriv_mtx);
830 LIST_FOREACH_SAFE(p, &cdev2priv(dev)->cdp_fdpriv, cdpd_list, p1) {
831 devfs_destroy_cdevpriv(p);
832 mtx_lock(&cdevpriv_mtx);
834 mtx_unlock(&cdevpriv_mtx);
839 bzero(&dev->__si_u, sizeof(dev->__si_u));
841 if (!(dev->si_flags & SI_ALIAS)) {
842 /* Remove from cdevsw list */
843 LIST_REMOVE(dev, si_list);
845 /* If cdevsw has no more struct cdev *'s, clean it */
846 if (LIST_EMPTY(&csw->d_devs)) {
848 wakeup(&csw->d_devs);
851 dev->si_flags &= ~SI_ALIAS;
852 dev->si_refcount--; /* Avoid race with dev_rel() */
854 if (dev->si_refcount > 0) {
855 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
857 dev_free_devlocked(dev);
862 destroy_dev(struct cdev *dev)
867 dev_unlock_and_free();
871 devtoname(struct cdev *dev)
877 if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') {
879 csw = dev_refthread(dev);
881 sprintf(p, "(%s)", csw->d_name);
885 mynor = dev2unit(dev);
886 if (mynor < 0 || mynor > 255)
887 sprintf(p, "/%#x", (u_int)mynor);
889 sprintf(p, "/%d", mynor);
891 return (dev->si_name);
895 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
900 if (bcmp(stem, name, i) != 0)
902 if (!isdigit(name[i]))
905 if (name[i] == '0' && isdigit(name[i+1]))
907 while (isdigit(name[i])) {
909 u += name[i++] - '0';
922 * Helper functions for cloning device drivers.
924 * The objective here is to make it unnecessary for the device drivers to
925 * use rman or similar to manage their unit number space. Due to the way
926 * we do "on-demand" devices, using rman or other "private" methods
927 * will be very tricky to lock down properly once we lock down this file.
929 * Instead we give the drivers these routines which puts the struct cdev *'s
930 * that are to be managed on their own list, and gives the driver the ability
931 * to ask for the first free unit number or a given specified unit number.
933 * In addition these routines support paired devices (pty, nmdm and similar)
934 * by respecting a number of "flag" bits in the minor number.
939 LIST_HEAD(,cdev) head;
943 clone_setup(struct clonedevs **cdp)
946 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
947 LIST_INIT(&(*cdp)->head);
951 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, struct cdev **dp, int extra)
953 struct clonedevs *cd;
954 struct cdev *dev, *ndev, *dl, *de;
957 KASSERT(*cdp != NULL,
958 ("clone_setup() not called in driver \"%s\"", csw->d_name));
959 KASSERT(!(extra & CLONE_UNITMASK),
960 ("Illegal extra bits (0x%x) in clone_create", extra));
961 KASSERT(*up <= CLONE_UNITMASK,
962 ("Too high unit (0x%x) in clone_create", *up));
963 KASSERT(csw->d_flags & D_NEEDMINOR,
964 ("clone_create() on cdevsw without minor numbers"));
968 * Search the list for a lot of things in one go:
969 * A preexisting match is returned immediately.
970 * The lowest free unit number if we are passed -1, and the place
971 * in the list where we should insert that new element.
972 * The place to insert a specified unit number, if applicable
973 * the end of the list.
976 ndev = devfs_alloc();
982 LIST_FOREACH(dev, &cd->head, si_clone) {
983 KASSERT(dev->si_flags & SI_CLONELIST,
984 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
986 if (u == (unit | extra)) {
992 if (unit == -1 && u == low) {
996 } else if (u < (unit | extra)) {
999 } else if (u > (unit | extra)) {
1005 unit = low & CLONE_UNITMASK;
1006 dev = newdev(csw, unit | extra, ndev);
1007 if (dev->si_flags & SI_CLONELIST) {
1008 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1009 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1010 LIST_FOREACH(dev, &cd->head, si_clone) {
1011 printf("\t%p %s\n", dev, dev->si_name);
1015 KASSERT(!(dev->si_flags & SI_CLONELIST),
1016 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1018 LIST_INSERT_BEFORE(dl, dev, si_clone);
1019 else if (de != NULL)
1020 LIST_INSERT_AFTER(de, dev, si_clone);
1022 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1023 dev->si_flags |= SI_CLONELIST;
1025 dev_unlock_and_free();
1030 * Kill everything still on the list. The driver should already have
1031 * disposed of any softc hung of the struct cdev *'s at this time.
1034 clone_cleanup(struct clonedevs **cdp)
1037 struct cdev_priv *cp;
1038 struct clonedevs *cd;
1044 while (!LIST_EMPTY(&cd->head)) {
1045 dev = LIST_FIRST(&cd->head);
1046 LIST_REMOVE(dev, si_clone);
1047 KASSERT(dev->si_flags & SI_CLONELIST,
1048 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1049 dev->si_flags &= ~SI_CLONELIST;
1050 cp = cdev2priv(dev);
1051 if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1052 cp->cdp_flags |= CDP_SCHED_DTR;
1053 KASSERT(dev->si_flags & SI_NAMED,
1054 ("Driver has goofed in cloning underways udev %x", dev->si_drv0));
1058 dev_unlock_and_free();
1063 static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1064 TAILQ_HEAD_INITIALIZER(dev_ddtr);
1065 static struct task dev_dtr_task;
1068 destroy_dev_tq(void *ctx, int pending)
1070 struct cdev_priv *cp;
1076 while (!TAILQ_EMPTY(&dev_ddtr)) {
1077 cp = TAILQ_FIRST(&dev_ddtr);
1079 KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1080 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1081 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list);
1082 cb = cp->cdp_dtr_cb;
1083 cb_arg = cp->cdp_dtr_cb_arg;
1085 dev_unlock_and_free();
1095 * devmtx shall be locked on entry. devmtx will be unlocked after
1099 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1101 struct cdev_priv *cp;
1103 mtx_assert(&devmtx, MA_OWNED);
1104 cp = cdev2priv(dev);
1105 if (cp->cdp_flags & CDP_SCHED_DTR) {
1110 cp->cdp_flags |= CDP_SCHED_DTR;
1111 cp->cdp_dtr_cb = cb;
1112 cp->cdp_dtr_cb_arg = arg;
1113 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1115 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1120 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1123 return (destroy_dev_sched_cbl(dev, cb, arg));
1127 destroy_dev_sched(struct cdev *dev)
1129 return (destroy_dev_sched_cb(dev, NULL, NULL));
1133 destroy_dev_drain(struct cdevsw *csw)
1137 while (!LIST_EMPTY(&csw->d_devs)) {
1138 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1144 drain_dev_clone_events(void)
1147 sx_xlock(&clone_drain_lock);
1148 sx_xunlock(&clone_drain_lock);
1152 devdtr_init(void *dummy __unused)
1155 TASK_INIT(&dev_dtr_task, 0, destroy_dev_tq, NULL);
1158 SYSINIT(devdtr, SI_SUB_DEVFS, SI_ORDER_SECOND, devdtr_init, NULL);