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>
52 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage");
55 static void destroy_devl(struct cdev *dev);
56 static int destroy_dev_sched_cbl(struct cdev *dev,
57 void (*cb)(void *), void *arg);
58 static void destroy_dev_tq(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 mtx_assert(&devmtx, MA_OWNED);
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 mtx_assert(&devmtx, MA_OWNED);
118 cdp = cdev2priv(cdev);
119 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list);
123 cdevsw_free_devlocked(struct cdevsw *csw)
126 mtx_assert(&devmtx, MA_OWNED);
127 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list);
138 dev_ref(struct cdev *dev)
141 mtx_assert(&devmtx, MA_NOTOWNED);
148 dev_refl(struct cdev *dev)
151 mtx_assert(&devmtx, MA_OWNED);
156 dev_rel(struct cdev *dev)
160 mtx_assert(&devmtx, MA_NOTOWNED);
163 KASSERT(dev->si_refcount >= 0,
164 ("dev_rel(%s) gave negative count", devtoname(dev)));
166 if (dev->si_usecount == 0 &&
167 (dev->si_flags & SI_CHEAPCLONE) && (dev->si_flags & SI_NAMED))
171 if (dev->si_devsw == NULL && dev->si_refcount == 0) {
172 LIST_REMOVE(dev, si_list);
181 dev_refthread(struct cdev *dev, int *ref)
184 struct cdev_priv *cdp;
186 mtx_assert(&devmtx, MA_NOTOWNED);
187 if ((dev->si_flags & SI_ETERNAL) != 0) {
189 return (dev->si_devsw);
194 cdp = cdev2priv(dev);
195 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0)
196 atomic_add_long(&dev->si_threadcount, 1);
206 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref)
209 struct cdev_priv *cdp;
212 mtx_assert(&devmtx, MA_NOTOWNED);
213 if ((vp->v_vflag & VV_ETERNALDEV) != 0) {
217 KASSERT((dev->si_flags & SI_ETERNAL) != 0,
218 ("Not eternal cdev"));
221 KASSERT(csw != NULL, ("Eternal cdev is destroyed"));
233 cdp = cdev2priv(dev);
234 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) {
237 atomic_add_long(&dev->si_threadcount, 1);
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 cdevsw *csw, int unit, struct cdev *si)
571 mtx_assert(&devmtx, MA_OWNED);
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) == unit) {
576 dev_free_devlocked(si);
583 LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
588 fini_cdevsw(struct cdevsw *devsw)
592 if (devsw->d_gianttrick != NULL) {
593 gt = devsw->d_gianttrick;
594 memcpy(devsw, gt, sizeof *devsw);
595 cdevsw_free_devlocked(gt);
596 devsw->d_gianttrick = NULL;
598 devsw->d_flags &= ~D_INIT;
602 prep_cdevsw(struct cdevsw *devsw, int flags)
606 mtx_assert(&devmtx, MA_OWNED);
607 if (devsw->d_flags & D_INIT)
609 if (devsw->d_flags & D_NEEDGIANT) {
611 dsw2 = malloc(sizeof *dsw2, M_DEVT,
612 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
614 if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
618 if (devsw->d_flags & D_INIT) {
620 cdevsw_free_devlocked(dsw2);
624 if (devsw->d_version != D_VERSION_03) {
626 "WARNING: Device driver \"%s\" has wrong version %s\n",
627 devsw->d_name == NULL ? "???" : devsw->d_name,
628 "and is disabled. Recompile KLD module.");
629 devsw->d_open = dead_open;
630 devsw->d_close = dead_close;
631 devsw->d_read = dead_read;
632 devsw->d_write = dead_write;
633 devsw->d_ioctl = dead_ioctl;
634 devsw->d_poll = dead_poll;
635 devsw->d_mmap = dead_mmap;
636 devsw->d_mmap_single = dead_mmap_single;
637 devsw->d_strategy = dead_strategy;
638 devsw->d_dump = dead_dump;
639 devsw->d_kqfilter = dead_kqfilter;
642 if (devsw->d_flags & D_NEEDGIANT) {
643 if (devsw->d_gianttrick == NULL) {
644 memcpy(dsw2, devsw, sizeof *dsw2);
645 devsw->d_gianttrick = dsw2;
650 #define FIXUP(member, noop, giant) \
652 if (devsw->member == NULL) { \
653 devsw->member = noop; \
654 } else if (devsw->d_flags & D_NEEDGIANT) \
655 devsw->member = giant; \
659 FIXUP(d_open, null_open, giant_open);
660 FIXUP(d_fdopen, NULL, giant_fdopen);
661 FIXUP(d_close, null_close, giant_close);
662 FIXUP(d_read, no_read, giant_read);
663 FIXUP(d_write, no_write, giant_write);
664 FIXUP(d_ioctl, no_ioctl, giant_ioctl);
665 FIXUP(d_poll, no_poll, giant_poll);
666 FIXUP(d_mmap, no_mmap, giant_mmap);
667 FIXUP(d_strategy, no_strategy, giant_strategy);
668 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter);
669 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single);
671 if (devsw->d_dump == NULL) devsw->d_dump = no_dump;
673 LIST_INIT(&devsw->d_devs);
675 devsw->d_flags |= D_INIT;
678 cdevsw_free_devlocked(dsw2);
683 prep_devname(struct cdev *dev, const char *fmt, va_list ap)
686 char *from, *q, *s, *to;
688 mtx_assert(&devmtx, MA_OWNED);
690 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap);
691 if (len > sizeof(dev->si_name) - 1)
692 return (ENAMETOOLONG);
694 /* Strip leading slashes. */
695 for (from = dev->si_name; *from == '/'; from++)
698 for (to = dev->si_name; *from != '\0'; from++, to++) {
700 * Spaces and double quotation marks cause
701 * problems for the devctl(4) protocol.
702 * Reject names containing those characters.
704 if (isspace(*from) || *from == '"')
706 /* Treat multiple sequential slashes as single. */
707 while (from[0] == '/' && from[1] == '/')
709 /* Trailing slash is considered invalid. */
710 if (from[0] == '/' && from[1] == '\0')
716 if (dev->si_name[0] == '\0')
719 /* Disallow "." and ".." components. */
720 for (s = dev->si_name;;) {
721 for (q = s; *q != '/' && *q != '\0'; q++)
723 if (q - s == 1 && s[0] == '.')
725 if (q - s == 2 && s[0] == '.' && s[1] == '.')
732 if (devfs_dev_exists(dev->si_name) != 0)
739 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
740 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
743 struct cdev *dev, *dev_new;
746 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
747 ("make_dev_credv: both WAITOK and NOWAIT specified"));
748 dev_new = devfs_alloc(flags);
752 res = prep_cdevsw(devsw, flags);
758 dev = newdev(devsw, unit, dev_new);
759 if ((dev->si_flags & SI_NAMED) == 0) {
760 res = prep_devname(dev, fmt, ap);
762 if ((flags & MAKEDEV_CHECKNAME) == 0) {
764 "make_dev_credv: bad si_name (error=%d, si_name=%s)",
767 if (dev == dev_new) {
768 LIST_REMOVE(dev, si_list);
776 if (flags & MAKEDEV_REF)
778 if (flags & MAKEDEV_ETERNAL)
779 dev->si_flags |= SI_ETERNAL;
780 if (dev->si_flags & SI_CHEAPCLONE &&
781 dev->si_flags & SI_NAMED) {
783 * This is allowed as it removes races and generally
784 * simplifies cloning devices.
787 dev_unlock_and_free();
791 KASSERT(!(dev->si_flags & SI_NAMED),
792 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
793 devsw->d_name, dev2unit(dev), devtoname(dev)));
794 dev->si_flags |= SI_NAMED;
796 dev->si_cred = crhold(cr);
802 clean_unrhdrl(devfs_inos);
803 dev_unlock_and_free();
805 notify_create(dev, flags);
812 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
813 const char *fmt, ...)
820 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
823 KASSERT(res == 0 && dev != NULL,
824 ("make_dev: failed make_dev_credv (error=%d)", res));
829 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
830 gid_t gid, int mode, const char *fmt, ...)
837 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
840 KASSERT(res == 0 && dev != NULL,
841 ("make_dev_cred: failed make_dev_credv (error=%d)", res));
846 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
847 uid_t uid, gid_t gid, int mode, const char *fmt, ...)
854 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
858 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
859 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
860 ("make_dev_credf: failed make_dev_credv (error=%d)", res));
861 return (res == 0 ? dev : NULL);
865 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw,
866 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
872 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
876 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
877 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
878 ("make_dev_p: failed make_dev_credv (error=%d)", res));
883 dev_dependsl(struct cdev *pdev, struct cdev *cdev)
886 cdev->si_parent = pdev;
887 cdev->si_flags |= SI_CHILD;
888 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings);
893 dev_depends(struct cdev *pdev, struct cdev *cdev)
897 dev_dependsl(pdev, cdev);
902 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev,
903 const char *fmt, va_list ap)
908 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL"));
909 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
910 ("make_dev_alias_v: both WAITOK and NOWAIT specified"));
911 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT |
912 MAKEDEV_CHECKNAME)) == 0,
913 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags));
915 dev = devfs_alloc(flags);
919 dev->si_flags |= SI_ALIAS;
920 error = prep_devname(dev, fmt, ap);
922 if ((flags & MAKEDEV_CHECKNAME) == 0) {
923 panic("make_dev_alias_v: bad si_name "
924 "(error=%d, si_name=%s)", error, dev->si_name);
930 dev->si_flags |= SI_NAMED;
932 dev_dependsl(pdev, dev);
933 clean_unrhdrl(devfs_inos);
936 notify_create(dev, flags);
943 make_dev_alias(struct cdev *pdev, const char *fmt, ...)
950 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap);
953 KASSERT(res == 0 && dev != NULL,
954 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res));
959 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev,
960 const char *fmt, ...)
966 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap);
972 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev,
973 struct cdev *old_alias, const char *physpath)
977 int max_parentpath_len;
979 int devfspathbuf_len;
985 physpath_len = strlen(physpath);
987 if (physpath_len == 0)
990 if (strncmp("id1,", physpath, 4) == 0) {
993 if (physpath_len == 0)
997 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1;
998 parentpath_len = strlen(pdev->si_name);
999 if (max_parentpath_len < parentpath_len) {
1001 printf("WARNING: Unable to alias %s "
1002 "to %s/%s - path too long\n",
1003 pdev->si_name, physpath, pdev->si_name);
1008 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK;
1009 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1;
1010 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags);
1011 if (devfspath == NULL) {
1016 sprintf(devfspath, "%s/%s", physpath, pdev->si_name);
1017 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) {
1018 /* Retain the existing alias. */
1023 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath);
1026 if (old_alias != NULL)
1027 destroy_dev(old_alias);
1028 if (devfspath != NULL)
1029 free(devfspath, M_DEVBUF);
1034 destroy_devl(struct cdev *dev)
1037 struct cdev_privdata *p;
1039 mtx_assert(&devmtx, MA_OWNED);
1040 KASSERT(dev->si_flags & SI_NAMED,
1041 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
1042 KASSERT((dev->si_flags & SI_ETERNAL) == 0,
1043 ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
1048 /* Remove name marking */
1049 dev->si_flags &= ~SI_NAMED;
1051 dev->si_refcount++; /* Avoid race with dev_rel() */
1053 /* If we are a child, remove us from the parents list */
1054 if (dev->si_flags & SI_CHILD) {
1055 LIST_REMOVE(dev, si_siblings);
1056 dev->si_flags &= ~SI_CHILD;
1059 /* Kill our children */
1060 while (!LIST_EMPTY(&dev->si_children))
1061 destroy_devl(LIST_FIRST(&dev->si_children));
1063 /* Remove from clone list */
1064 if (dev->si_flags & SI_CLONELIST) {
1065 LIST_REMOVE(dev, si_clone);
1066 dev->si_flags &= ~SI_CLONELIST;
1069 csw = dev->si_devsw;
1070 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */
1071 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
1073 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
1074 if (dev->si_threadcount)
1075 printf("Still %lu threads in %s\n",
1076 dev->si_threadcount, devtoname(dev));
1078 while (dev->si_threadcount != 0) {
1079 /* Use unique dummy wait ident */
1080 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10);
1084 notify_destroy(dev);
1085 mtx_lock(&cdevpriv_mtx);
1086 while ((p = LIST_FIRST(&cdev2priv(dev)->cdp_fdpriv)) != NULL) {
1087 devfs_destroy_cdevpriv(p);
1088 mtx_lock(&cdevpriv_mtx);
1090 mtx_unlock(&cdevpriv_mtx);
1095 bzero(&dev->__si_u, sizeof(dev->__si_u));
1097 if (!(dev->si_flags & SI_ALIAS)) {
1098 /* Remove from cdevsw list */
1099 LIST_REMOVE(dev, si_list);
1101 /* If cdevsw has no more struct cdev *'s, clean it */
1102 if (LIST_EMPTY(&csw->d_devs)) {
1104 wakeup(&csw->d_devs);
1107 dev->si_flags &= ~SI_ALIAS;
1108 dev->si_refcount--; /* Avoid race with dev_rel() */
1110 if (dev->si_refcount > 0) {
1111 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list);
1113 dev_free_devlocked(dev);
1118 destroy_dev(struct cdev *dev)
1121 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev");
1124 dev_unlock_and_free();
1128 devtoname(struct cdev *dev)
1131 return (dev->si_name);
1135 dev_stdclone(char *name, char **namep, const char *stem, int *unit)
1140 if (bcmp(stem, name, i) != 0)
1142 if (!isdigit(name[i]))
1145 if (name[i] == '0' && isdigit(name[i+1]))
1147 while (isdigit(name[i])) {
1149 u += name[i++] - '0';
1162 * Helper functions for cloning device drivers.
1164 * The objective here is to make it unnecessary for the device drivers to
1165 * use rman or similar to manage their unit number space. Due to the way
1166 * we do "on-demand" devices, using rman or other "private" methods
1167 * will be very tricky to lock down properly once we lock down this file.
1169 * Instead we give the drivers these routines which puts the struct cdev *'s
1170 * that are to be managed on their own list, and gives the driver the ability
1171 * to ask for the first free unit number or a given specified unit number.
1173 * In addition these routines support paired devices (pty, nmdm and similar)
1174 * by respecting a number of "flag" bits in the minor number.
1179 LIST_HEAD(,cdev) head;
1183 clone_setup(struct clonedevs **cdp)
1186 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO);
1187 LIST_INIT(&(*cdp)->head);
1191 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up,
1192 struct cdev **dp, int extra)
1194 struct clonedevs *cd;
1195 struct cdev *dev, *ndev, *dl, *de;
1198 KASSERT(*cdp != NULL,
1199 ("clone_setup() not called in driver \"%s\"", csw->d_name));
1200 KASSERT(!(extra & CLONE_UNITMASK),
1201 ("Illegal extra bits (0x%x) in clone_create", extra));
1202 KASSERT(*up <= CLONE_UNITMASK,
1203 ("Too high unit (0x%x) in clone_create", *up));
1204 KASSERT(csw->d_flags & D_NEEDMINOR,
1205 ("clone_create() on cdevsw without minor numbers"));
1209 * Search the list for a lot of things in one go:
1210 * A preexisting match is returned immediately.
1211 * The lowest free unit number if we are passed -1, and the place
1212 * in the list where we should insert that new element.
1213 * The place to insert a specified unit number, if applicable
1214 * the end of the list.
1217 ndev = devfs_alloc(MAKEDEV_WAITOK);
1219 prep_cdevsw(csw, MAKEDEV_WAITOK);
1223 LIST_FOREACH(dev, &cd->head, si_clone) {
1224 KASSERT(dev->si_flags & SI_CLONELIST,
1225 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1227 if (u == (unit | extra)) {
1233 if (unit == -1 && u == low) {
1237 } else if (u < (unit | extra)) {
1240 } else if (u > (unit | extra)) {
1246 unit = low & CLONE_UNITMASK;
1247 dev = newdev(csw, unit | extra, ndev);
1248 if (dev->si_flags & SI_CLONELIST) {
1249 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
1250 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
1251 LIST_FOREACH(dev, &cd->head, si_clone) {
1252 printf("\t%p %s\n", dev, dev->si_name);
1256 KASSERT(!(dev->si_flags & SI_CLONELIST),
1257 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name));
1259 LIST_INSERT_BEFORE(dl, dev, si_clone);
1260 else if (de != NULL)
1261 LIST_INSERT_AFTER(de, dev, si_clone);
1263 LIST_INSERT_HEAD(&cd->head, dev, si_clone);
1264 dev->si_flags |= SI_CLONELIST;
1266 dev_unlock_and_free();
1271 * Kill everything still on the list. The driver should already have
1272 * disposed of any softc hung of the struct cdev *'s at this time.
1275 clone_cleanup(struct clonedevs **cdp)
1278 struct cdev_priv *cp;
1279 struct clonedevs *cd;
1285 while (!LIST_EMPTY(&cd->head)) {
1286 dev = LIST_FIRST(&cd->head);
1287 LIST_REMOVE(dev, si_clone);
1288 KASSERT(dev->si_flags & SI_CLONELIST,
1289 ("Dev %p(%s) should be on clonelist", dev, dev->si_name));
1290 dev->si_flags &= ~SI_CLONELIST;
1291 cp = cdev2priv(dev);
1292 if (!(cp->cdp_flags & CDP_SCHED_DTR)) {
1293 cp->cdp_flags |= CDP_SCHED_DTR;
1294 KASSERT(dev->si_flags & SI_NAMED,
1295 ("Driver has goofed in cloning underways udev %x unit %x", dev2udev(dev), dev2unit(dev)));
1299 dev_unlock_and_free();
1304 static TAILQ_HEAD(, cdev_priv) dev_ddtr =
1305 TAILQ_HEAD_INITIALIZER(dev_ddtr);
1306 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL);
1309 destroy_dev_tq(void *ctx, int pending)
1311 struct cdev_priv *cp;
1317 while (!TAILQ_EMPTY(&dev_ddtr)) {
1318 cp = TAILQ_FIRST(&dev_ddtr);
1320 KASSERT(cp->cdp_flags & CDP_SCHED_DTR,
1321 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp));
1322 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list);
1323 cb = cp->cdp_dtr_cb;
1324 cb_arg = cp->cdp_dtr_cb_arg;
1326 dev_unlock_and_free();
1336 * devmtx shall be locked on entry. devmtx will be unlocked after
1340 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg)
1342 struct cdev_priv *cp;
1344 mtx_assert(&devmtx, MA_OWNED);
1345 cp = cdev2priv(dev);
1346 if (cp->cdp_flags & CDP_SCHED_DTR) {
1351 cp->cdp_flags |= CDP_SCHED_DTR;
1352 cp->cdp_dtr_cb = cb;
1353 cp->cdp_dtr_cb_arg = arg;
1354 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list);
1356 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task);
1361 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg)
1365 return (destroy_dev_sched_cbl(dev, cb, arg));
1369 destroy_dev_sched(struct cdev *dev)
1372 return (destroy_dev_sched_cb(dev, NULL, NULL));
1376 destroy_dev_drain(struct cdevsw *csw)
1380 while (!LIST_EMPTY(&csw->d_devs)) {
1381 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10);
1387 drain_dev_clone_events(void)
1390 sx_xlock(&clone_drain_lock);
1391 sx_xunlock(&clone_drain_lock);
1394 #include "opt_ddb.h"
1396 #include <sys/kernel.h>
1398 #include <ddb/ddb.h>
1400 DB_SHOW_COMMAND(cdev, db_show_cdev)
1402 struct cdev_priv *cdp;
1408 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
1410 db_printf("%s %p\n", dev->si_name, dev);
1417 dev = (struct cdev *)addr;
1418 cdp = cdev2priv(dev);
1419 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n",
1420 dev->si_name, dev->si_refcount, dev->si_usecount,
1421 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first);
1422 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n",
1423 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2);
1424 flags = dev->si_flags;
1425 #define SI_FLAG(flag) do { \
1426 if (flags & (flag)) { \
1427 if (buf[0] != '\0') \
1428 strlcat(buf, ", ", sizeof(buf)); \
1429 strlcat(buf, (#flag) + 3, sizeof(buf)); \
1434 SI_FLAG(SI_ETERNAL);
1437 SI_FLAG(SI_CHEAPCLONE);
1439 SI_FLAG(SI_DUMPDEV);
1440 SI_FLAG(SI_CLONELIST);
1441 db_printf("si_flags %s\n", buf);
1443 flags = cdp->cdp_flags;
1444 #define CDP_FLAG(flag) do { \
1445 if (flags & (flag)) { \
1446 if (buf[0] != '\0') \
1447 strlcat(buf, ", ", sizeof(buf)); \
1448 strlcat(buf, (#flag) + 4, sizeof(buf)); \
1453 CDP_FLAG(CDP_ACTIVE);
1454 CDP_FLAG(CDP_SCHED_DTR);
1455 db_printf("cdp_flags %s\n", buf);