1 /*-
2 * Copyright (c) 2000-2004
3 * Poul-Henning Kamp. All rights reserved.
4 * Copyright (c) 1989, 1992-1993, 1995
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software donated to Berkeley by
8 * Jan-Simon Pendry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95
32 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vnops.c 1.43
33 *
34 * $FreeBSD: releng/10.4/sys/fs/devfs/devfs_vnops.c 302078 2016-06-22 09:08:18Z kib $
35 */
36
37 /*
38 * TODO:
39 * mkdir: want it ?
40 */
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/conf.h>
45 #include <sys/dirent.h>
46 #include <sys/fcntl.h>
47 #include <sys/file.h>
48 #include <sys/filedesc.h>
49 #include <sys/filio.h>
50 #include <sys/jail.h>
51 #include <sys/kernel.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/mount.h>
55 #include <sys/namei.h>
56 #include <sys/priv.h>
57 #include <sys/proc.h>
58 #include <sys/stat.h>
59 #include <sys/sx.h>
60 #include <sys/sysctl.h>
61 #include <sys/time.h>
62 #include <sys/ttycom.h>
63 #include <sys/unistd.h>
64 #include <sys/vnode.h>
65
66 static struct vop_vector devfs_vnodeops;
67 static struct vop_vector devfs_specops;
68 static struct fileops devfs_ops_f;
69
70 #include <fs/devfs/devfs.h>
71 #include <fs/devfs/devfs_int.h>
72
73 #include <security/mac/mac_framework.h>
74
75 static MALLOC_DEFINE(M_CDEVPDATA, "DEVFSP", "Metainfo for cdev-fp data");
76
77 struct mtx devfs_de_interlock;
78 MTX_SYSINIT(devfs_de_interlock, &devfs_de_interlock, "devfs interlock", MTX_DEF);
79 struct sx clone_drain_lock;
80 SX_SYSINIT(clone_drain_lock, &clone_drain_lock, "clone events drain lock");
81 struct mtx cdevpriv_mtx;
82 MTX_SYSINIT(cdevpriv_mtx, &cdevpriv_mtx, "cdevpriv lock", MTX_DEF);
83
84 SYSCTL_DECL(_vfs_devfs);
85
86 static int devfs_dotimes;
87 SYSCTL_INT(_vfs_devfs, OID_AUTO, dotimes, CTLFLAG_RW,
88 &devfs_dotimes, 0, "Update timestamps on DEVFS with default precision");
89
90 /*
91 * Update devfs node timestamp. Note that updates are unlocked and
92 * stat(2) could see partially updated times.
93 */
94 static void
95 devfs_timestamp(struct timespec *tsp)
96 {
97 time_t ts;
98
99 if (devfs_dotimes) {
100 vfs_timestamp(tsp);
101 } else {
102 ts = time_second;
103 if (tsp->tv_sec != ts) {
104 tsp->tv_sec = ts;
105 tsp->tv_nsec = 0;
106 }
107 }
108 }
109
110 static int
111 devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp,
112 int *ref)
113 {
114
115 *dswp = devvn_refthread(fp->f_vnode, devp, ref);
116 if (*devp != fp->f_data) {
117 if (*dswp != NULL)
118 dev_relthread(*devp, *ref);
119 return (ENXIO);
120 }
121 KASSERT((*devp)->si_refcount > 0,
122 ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp)));
123 if (*dswp == NULL)
124 return (ENXIO);
125 curthread->td_fpop = fp;
126 return (0);
127 }
128
129 int
130 devfs_get_cdevpriv(void **datap)
131 {
132 struct file *fp;
133 struct cdev_privdata *p;
134 int error;
135
136 fp = curthread->td_fpop;
137 if (fp == NULL)
138 return (EBADF);
139 p = fp->f_cdevpriv;
140 if (p != NULL) {
141 error = 0;
142 *datap = p->cdpd_data;
143 } else
144 error = ENOENT;
145 return (error);
146 }
147
148 int
149 devfs_set_cdevpriv(void *priv, d_priv_dtor_t *priv_dtr)
150 {
151 struct file *fp;
152 struct cdev_priv *cdp;
153 struct cdev_privdata *p;
154 int error;
155
156 fp = curthread->td_fpop;
157 if (fp == NULL)
158 return (ENOENT);
159 cdp = cdev2priv((struct cdev *)fp->f_data);
160 p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK);
161 p->cdpd_data = priv;
162 p->cdpd_dtr = priv_dtr;
163 p->cdpd_fp = fp;
164 mtx_lock(&cdevpriv_mtx);
165 if (fp->f_cdevpriv == NULL) {
166 LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list);
167 fp->f_cdevpriv = p;
168 mtx_unlock(&cdevpriv_mtx);
169 error = 0;
170 } else {
171 mtx_unlock(&cdevpriv_mtx);
172 free(p, M_CDEVPDATA);
173 error = EBUSY;
174 }
175 return (error);
176 }
177
178 void
179 devfs_destroy_cdevpriv(struct cdev_privdata *p)
180 {
181
182 mtx_assert(&cdevpriv_mtx, MA_OWNED);
183 p->cdpd_fp->f_cdevpriv = NULL;
184 LIST_REMOVE(p, cdpd_list);
185 mtx_unlock(&cdevpriv_mtx);
186 (p->cdpd_dtr)(p->cdpd_data);
187 free(p, M_CDEVPDATA);
188 }
189
190 void
191 devfs_fpdrop(struct file *fp)
192 {
193 struct cdev_privdata *p;
194
195 mtx_lock(&cdevpriv_mtx);
196 if ((p = fp->f_cdevpriv) == NULL) {
197 mtx_unlock(&cdevpriv_mtx);
198 return;
199 }
200 devfs_destroy_cdevpriv(p);
201 }
202
203 void
204 devfs_clear_cdevpriv(void)
205 {
206 struct file *fp;
207
208 fp = curthread->td_fpop;
209 if (fp == NULL)
210 return;
211 devfs_fpdrop(fp);
212 }
213
214 /*
215 * On success devfs_populate_vp() returns with dmp->dm_lock held.
216 */
217 static int
218 devfs_populate_vp(struct vnode *vp)
219 {
220 struct devfs_dirent *de;
221 struct devfs_mount *dmp;
222 int locked;
223
224 ASSERT_VOP_LOCKED(vp, "devfs_populate_vp");
225
226 dmp = VFSTODEVFS(vp->v_mount);
227 locked = VOP_ISLOCKED(vp);
228
229 sx_xlock(&dmp->dm_lock);
230 DEVFS_DMP_HOLD(dmp);
231
232 /* Can't call devfs_populate() with the vnode lock held. */
233 VOP_UNLOCK(vp, 0);
234 devfs_populate(dmp);
235
236 sx_xunlock(&dmp->dm_lock);
237 vn_lock(vp, locked | LK_RETRY);
238 sx_xlock(&dmp->dm_lock);
239 if (DEVFS_DMP_DROP(dmp)) {
240 sx_xunlock(&dmp->dm_lock);
241 devfs_unmount_final(dmp);
242 return (ERESTART);
243 }
244 if ((vp->v_iflag & VI_DOOMED) != 0) {
245 sx_xunlock(&dmp->dm_lock);
246 return (ERESTART);
247 }
248 de = vp->v_data;
249 KASSERT(de != NULL,
250 ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed"));
251 if ((de->de_flags & DE_DOOMED) != 0) {
252 sx_xunlock(&dmp->dm_lock);
253 return (ERESTART);
254 }
255
256 return (0);
257 }
258
259 static int
260 devfs_vptocnp(struct vop_vptocnp_args *ap)
261 {
262 struct vnode *vp = ap->a_vp;
263 struct vnode **dvp = ap->a_vpp;
264 struct devfs_mount *dmp;
265 char *buf = ap->a_buf;
266 int *buflen = ap->a_buflen;
267 struct devfs_dirent *dd, *de;
268 int i, error;
269
270 dmp = VFSTODEVFS(vp->v_mount);
271
272 error = devfs_populate_vp(vp);
273 if (error != 0)
274 return (error);
275
276 i = *buflen;
277 dd = vp->v_data;
278
279 if (vp->v_type == VCHR) {
280 i -= strlen(dd->de_cdp->cdp_c.si_name);
281 if (i < 0) {
282 error = ENOMEM;
283 goto finished;
284 }
285 bcopy(dd->de_cdp->cdp_c.si_name, buf + i,
286 strlen(dd->de_cdp->cdp_c.si_name));
287 de = dd->de_dir;
288 } else if (vp->v_type == VDIR) {
289 if (dd == dmp->dm_rootdir) {
290 *dvp = vp;
291 vref(*dvp);
292 goto finished;
293 }
294 i -= dd->de_dirent->d_namlen;
295 if (i < 0) {
296 error = ENOMEM;
297 goto finished;
298 }
299 bcopy(dd->de_dirent->d_name, buf + i,
300 dd->de_dirent->d_namlen);
301 de = dd;
302 } else {
303 error = ENOENT;
304 goto finished;
305 }
306 *buflen = i;
307 de = devfs_parent_dirent(de);
308 if (de == NULL) {
309 error = ENOENT;
310 goto finished;
311 }
312 mtx_lock(&devfs_de_interlock);
313 *dvp = de->de_vnode;
314 if (*dvp != NULL) {
315 VI_LOCK(*dvp);
316 mtx_unlock(&devfs_de_interlock);
317 vholdl(*dvp);
318 VI_UNLOCK(*dvp);
319 vref(*dvp);
320 vdrop(*dvp);
321 } else {
322 mtx_unlock(&devfs_de_interlock);
323 error = ENOENT;
324 }
325 finished:
326 sx_xunlock(&dmp->dm_lock);
327 return (error);
328 }
329
330 /*
331 * Construct the fully qualified path name relative to the mountpoint.
332 * If a NULL cnp is provided, no '/' is appended to the resulting path.
333 */
334 char *
335 devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd,
336 struct componentname *cnp)
337 {
338 int i;
339 struct devfs_dirent *de;
340
341 sx_assert(&dmp->dm_lock, SA_LOCKED);
342
343 i = SPECNAMELEN;
344 buf[i] = '\0';
345 if (cnp != NULL)
346 i -= cnp->cn_namelen;
347 if (i < 0)
348 return (NULL);
349 if (cnp != NULL)
350 bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen);
351 de = dd;
352 while (de != dmp->dm_rootdir) {
353 if (cnp != NULL || i < SPECNAMELEN) {
354 i--;
355 if (i < 0)
356 return (NULL);
357 buf[i] = '/';
358 }
359 i -= de->de_dirent->d_namlen;
360 if (i < 0)
361 return (NULL);
362 bcopy(de->de_dirent->d_name, buf + i,
363 de->de_dirent->d_namlen);
364 de = devfs_parent_dirent(de);
365 if (de == NULL)
366 return (NULL);
367 }
368 return (buf + i);
369 }
370
371 static int
372 devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp,
373 struct devfs_dirent *de)
374 {
375 int not_found;
376
377 not_found = 0;
378 if (de->de_flags & DE_DOOMED)
379 not_found = 1;
380 if (DEVFS_DE_DROP(de)) {
381 KASSERT(not_found == 1, ("DEVFS de dropped but not doomed"));
382 devfs_dirent_free(de);
383 }
384 if (DEVFS_DMP_DROP(dmp)) {
385 KASSERT(not_found == 1,
386 ("DEVFS mount struct freed before dirent"));
387 not_found = 2;
388 sx_xunlock(&dmp->dm_lock);
389 devfs_unmount_final(dmp);
390 }
391 if (not_found == 1 || (drop_dm_lock && not_found != 2))
392 sx_unlock(&dmp->dm_lock);
393 return (not_found);
394 }
395
396 static void
397 devfs_insmntque_dtr(struct vnode *vp, void *arg)
398 {
399 struct devfs_dirent *de;
400
401 de = (struct devfs_dirent *)arg;
402 mtx_lock(&devfs_de_interlock);
403 vp->v_data = NULL;
404 de->de_vnode = NULL;
405 mtx_unlock(&devfs_de_interlock);
406 vgone(vp);
407 vput(vp);
408 }
409
410 /*
411 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops
412 * it on return.
413 */
414 int
415 devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode,
416 struct vnode **vpp)
417 {
418 int error;
419 struct vnode *vp;
420 struct cdev *dev;
421 struct devfs_mount *dmp;
422 struct cdevsw *dsw;
423
424 dmp = VFSTODEVFS(mp);
425 if (de->de_flags & DE_DOOMED) {
426 sx_xunlock(&dmp->dm_lock);
427 return (ENOENT);
428 }
429 loop:
430 DEVFS_DE_HOLD(de);
431 DEVFS_DMP_HOLD(dmp);
432 mtx_lock(&devfs_de_interlock);
433 vp = de->de_vnode;
434 if (vp != NULL) {
435 VI_LOCK(vp);
436 mtx_unlock(&devfs_de_interlock);
437 sx_xunlock(&dmp->dm_lock);
438 vget(vp, lockmode | LK_INTERLOCK | LK_RETRY, curthread);
439 sx_xlock(&dmp->dm_lock);
440 if (devfs_allocv_drop_refs(0, dmp, de)) {
441 vput(vp);
442 return (ENOENT);
443 }
444 else if ((vp->v_iflag & VI_DOOMED) != 0) {
445 mtx_lock(&devfs_de_interlock);
446 if (de->de_vnode == vp) {
447 de->de_vnode = NULL;
448 vp->v_data = NULL;
449 }
450 mtx_unlock(&devfs_de_interlock);
451 vput(vp);
452 goto loop;
453 }
454 sx_xunlock(&dmp->dm_lock);
455 *vpp = vp;
456 return (0);
457 }
458 mtx_unlock(&devfs_de_interlock);
459 if (de->de_dirent->d_type == DT_CHR) {
460 if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) {
461 devfs_allocv_drop_refs(1, dmp, de);
462 return (ENOENT);
463 }
464 dev = &de->de_cdp->cdp_c;
465 } else {
466 dev = NULL;
467 }
468 error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp);
469 if (error != 0) {
470 devfs_allocv_drop_refs(1, dmp, de);
471 printf("devfs_allocv: failed to allocate new vnode\n");
472 return (error);
473 }
474
475 if (de->de_dirent->d_type == DT_CHR) {
476 vp->v_type = VCHR;
477 VI_LOCK(vp);
478 dev_lock();
479 dev_refl(dev);
480 /* XXX: v_rdev should be protect by vnode lock */
481 vp->v_rdev = dev;
482 KASSERT(vp->v_usecount == 1,
483 ("%s %d (%d)\n", __func__, __LINE__, vp->v_usecount));
484 dev->si_usecount += vp->v_usecount;
485 /* Special casing of ttys for deadfs. Probably redundant. */
486 dsw = dev->si_devsw;
487 if (dsw != NULL && (dsw->d_flags & D_TTY) != 0)
488 vp->v_vflag |= VV_ISTTY;
489 dev_unlock();
490 VI_UNLOCK(vp);
491 if ((dev->si_flags & SI_ETERNAL) != 0)
492 vp->v_vflag |= VV_ETERNALDEV;
493 vp->v_op = &devfs_specops;
494 } else if (de->de_dirent->d_type == DT_DIR) {
495 vp->v_type = VDIR;
496 } else if (de->de_dirent->d_type == DT_LNK) {
497 vp->v_type = VLNK;
498 } else {
499 vp->v_type = VBAD;
500 }
501 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS);
502 VN_LOCK_ASHARE(vp);
503 mtx_lock(&devfs_de_interlock);
504 vp->v_data = de;
505 de->de_vnode = vp;
506 mtx_unlock(&devfs_de_interlock);
507 error = insmntque1(vp, mp, devfs_insmntque_dtr, de);
508 if (error != 0) {
509 (void) devfs_allocv_drop_refs(1, dmp, de);
510 return (error);
511 }
512 if (devfs_allocv_drop_refs(0, dmp, de)) {
513 vput(vp);
514 return (ENOENT);
515 }
516 #ifdef MAC
517 mac_devfs_vnode_associate(mp, de, vp);
518 #endif
519 sx_xunlock(&dmp->dm_lock);
520 *vpp = vp;
521 return (0);
522 }
523
524 static int
525 devfs_access(struct vop_access_args *ap)
526 {
527 struct vnode *vp = ap->a_vp;
528 struct devfs_dirent *de;
529 int error;
530
531 de = vp->v_data;
532 if (vp->v_type == VDIR)
533 de = de->de_dir;
534
535 error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid,
536 ap->a_accmode, ap->a_cred, NULL);
537 if (error == 0)
538 return (0);
539 if (error != EACCES)
540 return (error);
541 /* We do, however, allow access to the controlling terminal */
542 if (!(ap->a_td->td_proc->p_flag & P_CONTROLT))
543 return (error);
544 if (ap->a_td->td_proc->p_session->s_ttydp == de->de_cdp)
545 return (0);
546 return (error);
547 }
548
549 /* ARGSUSED */
550 static int
551 devfs_close(struct vop_close_args *ap)
552 {
553 struct vnode *vp = ap->a_vp, *oldvp;
554 struct thread *td = ap->a_td;
555 struct cdev *dev = vp->v_rdev;
556 struct cdevsw *dsw;
557 int vp_locked, error, ref;
558
559 /*
560 * XXX: Don't call d_close() if we were called because of
561 * XXX: insmntque1() failure.
562 */
563 if (vp->v_data == NULL)
564 return (0);
565
566 /*
567 * Hack: a tty device that is a controlling terminal
568 * has a reference from the session structure.
569 * We cannot easily tell that a character device is
570 * a controlling terminal, unless it is the closing
571 * process' controlling terminal. In that case,
572 * if the reference count is 2 (this last descriptor
573 * plus the session), release the reference from the session.
574 */
575 oldvp = NULL;
576 sx_xlock(&proctree_lock);
577 if (td && vp == td->td_proc->p_session->s_ttyvp) {
578 SESS_LOCK(td->td_proc->p_session);
579 VI_LOCK(vp);
580 if (count_dev(dev) == 2 && (vp->v_iflag & VI_DOOMED) == 0) {
581 td->td_proc->p_session->s_ttyvp = NULL;
582 td->td_proc->p_session->s_ttydp = NULL;
583 oldvp = vp;
584 }
585 VI_UNLOCK(vp);
586 SESS_UNLOCK(td->td_proc->p_session);
587 }
588 sx_xunlock(&proctree_lock);
589 if (oldvp != NULL)
590 vrele(oldvp);
591 /*
592 * We do not want to really close the device if it
593 * is still in use unless we are trying to close it
594 * forcibly. Since every use (buffer, vnode, swap, cmap)
595 * holds a reference to the vnode, and because we mark
596 * any other vnodes that alias this device, when the
597 * sum of the reference counts on all the aliased
598 * vnodes descends to one, we are on last close.
599 */
600 dsw = dev_refthread(dev, &ref);
601 if (dsw == NULL)
602 return (ENXIO);
603 VI_LOCK(vp);
604 if (vp->v_iflag & VI_DOOMED) {
605 /* Forced close. */
606 } else if (dsw->d_flags & D_TRACKCLOSE) {
607 /* Keep device updated on status. */
608 } else if (count_dev(dev) > 1) {
609 VI_UNLOCK(vp);
610 dev_relthread(dev, ref);
611 return (0);
612 }
613 vholdl(vp);
614 VI_UNLOCK(vp);
615 vp_locked = VOP_ISLOCKED(vp);
616 VOP_UNLOCK(vp, 0);
617 KASSERT(dev->si_refcount > 0,
618 ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev)));
619 error = dsw->d_close(dev, ap->a_fflag, S_IFCHR, td);
620 dev_relthread(dev, ref);
621 vn_lock(vp, vp_locked | LK_RETRY);
622 vdrop(vp);
623 return (error);
624 }
625
626 static int
627 devfs_close_f(struct file *fp, struct thread *td)
628 {
629 int error;
630 struct file *fpop;
631
632 /*
633 * NB: td may be NULL if this descriptor is closed due to
634 * garbage collection from a closed UNIX domain socket.
635 */
636 fpop = curthread->td_fpop;
637 curthread->td_fpop = fp;
638 error = vnops.fo_close(fp, td);
639 curthread->td_fpop = fpop;
640
641 /*
642 * The f_cdevpriv cannot be assigned non-NULL value while we
643 * are destroying the file.
644 */
645 if (fp->f_cdevpriv != NULL)
646 devfs_fpdrop(fp);
647 return (error);
648 }
649
650 static int
651 devfs_fsync(struct vop_fsync_args *ap)
652 {
653 int error;
654 struct bufobj *bo;
655 struct devfs_dirent *de;
656
657 if (!vn_isdisk(ap->a_vp, &error)) {
658 bo = &ap->a_vp->v_bufobj;
659 de = ap->a_vp->v_data;
660 if (error == ENXIO && bo->bo_dirty.bv_cnt > 0) {
661 printf("Device %s went missing before all of the data "
662 "could be written to it; expect data loss.\n",
663 de->de_dirent->d_name);
664
665 error = vop_stdfsync(ap);
666 if (bo->bo_dirty.bv_cnt != 0 || error != 0)
667 panic("devfs_fsync: vop_stdfsync failed.");
668 }
669
670 return (0);
671 }
672
673 return (vop_stdfsync(ap));
674 }
675
676 static int
677 devfs_getattr(struct vop_getattr_args *ap)
678 {
679 struct vnode *vp = ap->a_vp;
680 struct vattr *vap = ap->a_vap;
681 int error;
682 struct devfs_dirent *de;
683 struct devfs_mount *dmp;
684 struct cdev *dev;
685
686 error = devfs_populate_vp(vp);
687 if (error != 0)
688 return (error);
689
690 dmp = VFSTODEVFS(vp->v_mount);
691 sx_xunlock(&dmp->dm_lock);
692
693 de = vp->v_data;
694 KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp));
695 if (vp->v_type == VDIR) {
696 de = de->de_dir;
697 KASSERT(de != NULL,
698 ("Null dir dirent in devfs_getattr vp=%p", vp));
699 }
700 vap->va_uid = de->de_uid;
701 vap->va_gid = de->de_gid;
702 vap->va_mode = de->de_mode;
703 if (vp->v_type == VLNK)
704 vap->va_size = strlen(de->de_symlink);
705 else if (vp->v_type == VDIR)
706 vap->va_size = vap->va_bytes = DEV_BSIZE;
707 else
708 vap->va_size = 0;
709 if (vp->v_type != VDIR)
710 vap->va_bytes = 0;
711 vap->va_blocksize = DEV_BSIZE;
712 vap->va_type = vp->v_type;
713
714 #define fix(aa) \
715 do { \
716 if ((aa).tv_sec <= 3600) { \
717 (aa).tv_sec = boottime.tv_sec; \
718 (aa).tv_nsec = boottime.tv_usec * 1000; \
719 } \
720 } while (0)
721
722 if (vp->v_type != VCHR) {
723 fix(de->de_atime);
724 vap->va_atime = de->de_atime;
725 fix(de->de_mtime);
726 vap->va_mtime = de->de_mtime;
727 fix(de->de_ctime);
728 vap->va_ctime = de->de_ctime;
729 } else {
730 dev = vp->v_rdev;
731 fix(dev->si_atime);
732 vap->va_atime = dev->si_atime;
733 fix(dev->si_mtime);
734 vap->va_mtime = dev->si_mtime;
735 fix(dev->si_ctime);
736 vap->va_ctime = dev->si_ctime;
737
738 vap->va_rdev = cdev2priv(dev)->cdp_inode;
739 }
740 vap->va_gen = 0;
741 vap->va_flags = 0;
742 vap->va_filerev = 0;
743 vap->va_nlink = de->de_links;
744 vap->va_fileid = de->de_inode;
745
746 return (error);
747 }
748
749 /* ARGSUSED */
750 static int
751 devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td)
752 {
753 struct cdev *dev;
754 struct cdevsw *dsw;
755 struct vnode *vp;
756 struct vnode *vpold;
757 int error, i, ref;
758 const char *p;
759 struct fiodgname_arg *fgn;
760 struct file *fpop;
761
762 fpop = td->td_fpop;
763 error = devfs_fp_check(fp, &dev, &dsw, &ref);
764 if (error != 0) {
765 error = vnops.fo_ioctl(fp, com, data, cred, td);
766 return (error);
767 }
768
769 if (com == FIODTYPE) {
770 *(int *)data = dsw->d_flags & D_TYPEMASK;
771 td->td_fpop = fpop;
772 dev_relthread(dev, ref);
773 return (0);
774 } else if (com == FIODGNAME) {
775 fgn = data;
776 p = devtoname(dev);
777 i = strlen(p) + 1;
778 if (i > fgn->len)
779 error = EINVAL;
780 else
781 error = copyout(p, fgn->buf, i);
782 td->td_fpop = fpop;
783 dev_relthread(dev, ref);
784 return (error);
785 }
786 error = dsw->d_ioctl(dev, com, data, fp->f_flag, td);
787 td->td_fpop = NULL;
788 dev_relthread(dev, ref);
789 if (error == ENOIOCTL)
790 error = ENOTTY;
791 if (error == 0 && com == TIOCSCTTY) {
792 vp = fp->f_vnode;
793
794 /* Do nothing if reassigning same control tty */
795 sx_slock(&proctree_lock);
796 if (td->td_proc->p_session->s_ttyvp == vp) {
797 sx_sunlock(&proctree_lock);
798 return (0);
799 }
800
801 vpold = td->td_proc->p_session->s_ttyvp;
802 VREF(vp);
803 SESS_LOCK(td->td_proc->p_session);
804 td->td_proc->p_session->s_ttyvp = vp;
805 td->td_proc->p_session->s_ttydp = cdev2priv(dev);
806 SESS_UNLOCK(td->td_proc->p_session);
807
808 sx_sunlock(&proctree_lock);
809
810 /* Get rid of reference to old control tty */
811 if (vpold)
812 vrele(vpold);
813 }
814 return (error);
815 }
816
817 /* ARGSUSED */
818 static int
819 devfs_kqfilter_f(struct file *fp, struct knote *kn)
820 {
821 struct cdev *dev;
822 struct cdevsw *dsw;
823 int error, ref;
824 struct file *fpop;
825 struct thread *td;
826
827 td = curthread;
828 fpop = td->td_fpop;
829 error = devfs_fp_check(fp, &dev, &dsw, &ref);
830 if (error)
831 return (error);
832 error = dsw->d_kqfilter(dev, kn);
833 td->td_fpop = fpop;
834 dev_relthread(dev, ref);
835 return (error);
836 }
837
838 static inline int
839 devfs_prison_check(struct devfs_dirent *de, struct thread *td)
840 {
841 struct cdev_priv *cdp;
842 struct ucred *dcr;
843 int error;
844
845 cdp = de->de_cdp;
846 if (cdp == NULL)
847 return (0);
848 dcr = cdp->cdp_c.si_cred;
849 if (dcr == NULL)
850 return (0);
851
852 error = prison_check(td->td_ucred, dcr);
853 if (error == 0)
854 return (0);
855 /* We do, however, allow access to the controlling terminal */
856 if (!(td->td_proc->p_flag & P_CONTROLT))
857 return (error);
858 if (td->td_proc->p_session->s_ttydp == cdp)
859 return (0);
860 return (error);
861 }
862
863 static int
864 devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock)
865 {
866 struct componentname *cnp;
867 struct vnode *dvp, **vpp;
868 struct thread *td;
869 struct devfs_dirent *de, *dd;
870 struct devfs_dirent **dde;
871 struct devfs_mount *dmp;
872 struct cdev *cdev;
873 int error, flags, nameiop, dvplocked;
874 char specname[SPECNAMELEN + 1], *pname;
875
876 cnp = ap->a_cnp;
877 vpp = ap->a_vpp;
878 dvp = ap->a_dvp;
879 pname = cnp->cn_nameptr;
880 td = cnp->cn_thread;
881 flags = cnp->cn_flags;
882 nameiop = cnp->cn_nameiop;
883 dmp = VFSTODEVFS(dvp->v_mount);
884 dd = dvp->v_data;
885 *vpp = NULLVP;
886
887 if ((flags & ISLASTCN) && nameiop == RENAME)
888 return (EOPNOTSUPP);
889
890 if (dvp->v_type != VDIR)
891 return (ENOTDIR);
892
893 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT))
894 return (EIO);
895
896 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td);
897 if (error)
898 return (error);
899
900 if (cnp->cn_namelen == 1 && *pname == '.') {
901 if ((flags & ISLASTCN) && nameiop != LOOKUP)
902 return (EINVAL);
903 *vpp = dvp;
904 VREF(dvp);
905 return (0);
906 }
907
908 if (flags & ISDOTDOT) {
909 if ((flags & ISLASTCN) && nameiop != LOOKUP)
910 return (EINVAL);
911 de = devfs_parent_dirent(dd);
912 if (de == NULL)
913 return (ENOENT);
914 dvplocked = VOP_ISLOCKED(dvp);
915 VOP_UNLOCK(dvp, 0);
916 error = devfs_allocv(de, dvp->v_mount,
917 cnp->cn_lkflags & LK_TYPE_MASK, vpp);
918 *dm_unlock = 0;
919 vn_lock(dvp, dvplocked | LK_RETRY);
920 return (error);
921 }
922
923 dd = dvp->v_data;
924 de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0);
925 while (de == NULL) { /* While(...) so we can use break */
926
927 if (nameiop == DELETE)
928 return (ENOENT);
929
930 /*
931 * OK, we didn't have an entry for the name we were asked for
932 * so we try to see if anybody can create it on demand.
933 */
934 pname = devfs_fqpn(specname, dmp, dd, cnp);
935 if (pname == NULL)
936 break;
937
938 cdev = NULL;
939 DEVFS_DMP_HOLD(dmp);
940 sx_xunlock(&dmp->dm_lock);
941 sx_slock(&clone_drain_lock);
942 EVENTHANDLER_INVOKE(dev_clone,
943 td->td_ucred, pname, strlen(pname), &cdev);
944 sx_sunlock(&clone_drain_lock);
945
946 if (cdev == NULL)
947 sx_xlock(&dmp->dm_lock);
948 else if (devfs_populate_vp(dvp) != 0) {
949 *dm_unlock = 0;
950 sx_xlock(&dmp->dm_lock);
951 if (DEVFS_DMP_DROP(dmp)) {
952 sx_xunlock(&dmp->dm_lock);
953 devfs_unmount_final(dmp);
954 } else
955 sx_xunlock(&dmp->dm_lock);
956 dev_rel(cdev);
957 return (ENOENT);
958 }
959 if (DEVFS_DMP_DROP(dmp)) {
960 *dm_unlock = 0;
961 sx_xunlock(&dmp->dm_lock);
962 devfs_unmount_final(dmp);
963 if (cdev != NULL)
964 dev_rel(cdev);
965 return (ENOENT);
966 }
967
968 if (cdev == NULL)
969 break;
970
971 dev_lock();
972 dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx];
973 if (dde != NULL && *dde != NULL)
974 de = *dde;
975 dev_unlock();
976 dev_rel(cdev);
977 break;
978 }
979
980 if (de == NULL || de->de_flags & DE_WHITEOUT) {
981 if ((nameiop == CREATE || nameiop == RENAME) &&
982 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) {
983 cnp->cn_flags |= SAVENAME;
984 return (EJUSTRETURN);
985 }
986 return (ENOENT);
987 }
988
989 if (devfs_prison_check(de, td))
990 return (ENOENT);
991
992 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) {
993 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td);
994 if (error)
995 return (error);
996 if (*vpp == dvp) {
997 VREF(dvp);
998 *vpp = dvp;
999 return (0);
1000 }
1001 }
1002 error = devfs_allocv(de, dvp->v_mount, cnp->cn_lkflags & LK_TYPE_MASK,
1003 vpp);
1004 *dm_unlock = 0;
1005 return (error);
1006 }
1007
1008 static int
1009 devfs_lookup(struct vop_lookup_args *ap)
1010 {
1011 int j;
1012 struct devfs_mount *dmp;
1013 int dm_unlock;
1014
1015 if (devfs_populate_vp(ap->a_dvp) != 0)
1016 return (ENOTDIR);
1017
1018 dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1019 dm_unlock = 1;
1020 j = devfs_lookupx(ap, &dm_unlock);
1021 if (dm_unlock == 1)
1022 sx_xunlock(&dmp->dm_lock);
1023 return (j);
1024 }
1025
1026 static int
1027 devfs_mknod(struct vop_mknod_args *ap)
1028 {
1029 struct componentname *cnp;
1030 struct vnode *dvp, **vpp;
1031 struct devfs_dirent *dd, *de;
1032 struct devfs_mount *dmp;
1033 int error;
1034
1035 /*
1036 * The only type of node we should be creating here is a
1037 * character device, for anything else return EOPNOTSUPP.
1038 */
1039 if (ap->a_vap->va_type != VCHR)
1040 return (EOPNOTSUPP);
1041 dvp = ap->a_dvp;
1042 dmp = VFSTODEVFS(dvp->v_mount);
1043
1044 cnp = ap->a_cnp;
1045 vpp = ap->a_vpp;
1046 dd = dvp->v_data;
1047
1048 error = ENOENT;
1049 sx_xlock(&dmp->dm_lock);
1050 TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
1051 if (cnp->cn_namelen != de->de_dirent->d_namlen)
1052 continue;
1053 if (de->de_dirent->d_type == DT_CHR &&
1054 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0)
1055 continue;
1056 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name,
1057 de->de_dirent->d_namlen) != 0)
1058 continue;
1059 if (de->de_flags & DE_WHITEOUT)
1060 break;
1061 goto notfound;
1062 }
1063 if (de == NULL)
1064 goto notfound;
1065 de->de_flags &= ~DE_WHITEOUT;
1066 error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp);
1067 return (error);
1068 notfound:
1069 sx_xunlock(&dmp->dm_lock);
1070 return (error);
1071 }
1072
1073 /* ARGSUSED */
1074 static int
1075 devfs_open(struct vop_open_args *ap)
1076 {
1077 struct thread *td = ap->a_td;
1078 struct vnode *vp = ap->a_vp;
1079 struct cdev *dev = vp->v_rdev;
1080 struct file *fp = ap->a_fp;
1081 int error, ref, vlocked;
1082 struct cdevsw *dsw;
1083 struct file *fpop;
1084 struct mtx *mtxp;
1085
1086 if (vp->v_type == VBLK)
1087 return (ENXIO);
1088
1089 if (dev == NULL)
1090 return (ENXIO);
1091
1092 /* Make this field valid before any I/O in d_open. */
1093 if (dev->si_iosize_max == 0)
1094 dev->si_iosize_max = DFLTPHYS;
1095
1096 dsw = dev_refthread(dev, &ref);
1097 if (dsw == NULL)
1098 return (ENXIO);
1099 if (fp == NULL && dsw->d_fdopen != NULL) {
1100 dev_relthread(dev, ref);
1101 return (ENXIO);
1102 }
1103
1104 vlocked = VOP_ISLOCKED(vp);
1105 VOP_UNLOCK(vp, 0);
1106
1107 fpop = td->td_fpop;
1108 td->td_fpop = fp;
1109 if (fp != NULL) {
1110 fp->f_data = dev;
1111 fp->f_vnode = vp;
1112 }
1113 if (dsw->d_fdopen != NULL)
1114 error = dsw->d_fdopen(dev, ap->a_mode, td, fp);
1115 else
1116 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td);
1117 /* Clean up any cdevpriv upon error. */
1118 if (error != 0)
1119 devfs_clear_cdevpriv();
1120 td->td_fpop = fpop;
1121
1122 vn_lock(vp, vlocked | LK_RETRY);
1123 dev_relthread(dev, ref);
1124 if (error != 0) {
1125 if (error == ERESTART)
1126 error = EINTR;
1127 return (error);
1128 }
1129
1130 #if 0 /* /dev/console */
1131 KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp"));
1132 #else
1133 if (fp == NULL)
1134 return (error);
1135 #endif
1136 if (fp->f_ops == &badfileops)
1137 finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f);
1138 mtxp = mtx_pool_find(mtxpool_sleep, fp);
1139
1140 /*
1141 * Hint to the dofilewrite() to not force the buffer draining
1142 * on the writer to the file. Most likely, the write would
1143 * not need normal buffers.
1144 */
1145 mtx_lock(mtxp);
1146 fp->f_vnread_flags |= FDEVFS_VNODE;
1147 mtx_unlock(mtxp);
1148 return (error);
1149 }
1150
1151 static int
1152 devfs_pathconf(struct vop_pathconf_args *ap)
1153 {
1154
1155 switch (ap->a_name) {
1156 case _PC_MAC_PRESENT:
1157 #ifdef MAC
1158 /*
1159 * If MAC is enabled, devfs automatically supports
1160 * trivial non-persistant label storage.
1161 */
1162 *ap->a_retval = 1;
1163 #else
1164 *ap->a_retval = 0;
1165 #endif
1166 return (0);
1167 default:
1168 return (vop_stdpathconf(ap));
1169 }
1170 /* NOTREACHED */
1171 }
1172
1173 /* ARGSUSED */
1174 static int
1175 devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td)
1176 {
1177 struct cdev *dev;
1178 struct cdevsw *dsw;
1179 int error, ref;
1180 struct file *fpop;
1181
1182 fpop = td->td_fpop;
1183 error = devfs_fp_check(fp, &dev, &dsw, &ref);
1184 if (error != 0) {
1185 error = vnops.fo_poll(fp, events, cred, td);
1186 return (error);
1187 }
1188 error = dsw->d_poll(dev, events, td);
1189 td->td_fpop = fpop;
1190 dev_relthread(dev, ref);
1191 return(error);
1192 }
1193
1194 /*
1195 * Print out the contents of a special device vnode.
1196 */
1197 static int
1198 devfs_print(struct vop_print_args *ap)
1199 {
1200
1201 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev));
1202 return (0);
1203 }
1204
1205 static int
1206 devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred,
1207 int flags, struct thread *td)
1208 {
1209 struct cdev *dev;
1210 int ioflag, error, ref;
1211 ssize_t resid;
1212 struct cdevsw *dsw;
1213 struct file *fpop;
1214
1215 if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1216 return (EINVAL);
1217 fpop = td->td_fpop;
1218 error = devfs_fp_check(fp, &dev, &dsw, &ref);
1219 if (error != 0) {
1220 error = vnops.fo_read(fp, uio, cred, flags, td);
1221 return (error);
1222 }
1223 resid = uio->uio_resid;
1224 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT);
1225 if (ioflag & O_DIRECT)
1226 ioflag |= IO_DIRECT;
1227
1228 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1229 error = dsw->d_read(dev, uio, ioflag);
1230 if (uio->uio_resid != resid || (error == 0 && resid != 0))
1231 devfs_timestamp(&dev->si_atime);
1232 td->td_fpop = fpop;
1233 dev_relthread(dev, ref);
1234
1235 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF);
1236 return (error);
1237 }
1238
1239 static int
1240 devfs_readdir(struct vop_readdir_args *ap)
1241 {
1242 int error;
1243 struct uio *uio;
1244 struct dirent *dp;
1245 struct devfs_dirent *dd;
1246 struct devfs_dirent *de;
1247 struct devfs_mount *dmp;
1248 off_t off;
1249 int *tmp_ncookies = NULL;
1250
1251 if (ap->a_vp->v_type != VDIR)
1252 return (ENOTDIR);
1253
1254 uio = ap->a_uio;
1255 if (uio->uio_offset < 0)
1256 return (EINVAL);
1257
1258 /*
1259 * XXX: This is a temporary hack to get around this filesystem not
1260 * supporting cookies. We store the location of the ncookies pointer
1261 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent()
1262 * and set the number of cookies to 0. We then set the pointer to
1263 * NULL so that vfs_read_dirent doesn't try to call realloc() on
1264 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies
1265 * pointer to its original location before returning to the caller.
1266 */
1267 if (ap->a_ncookies != NULL) {
1268 tmp_ncookies = ap->a_ncookies;
1269 *ap->a_ncookies = 0;
1270 ap->a_ncookies = NULL;
1271 }
1272
1273 dmp = VFSTODEVFS(ap->a_vp->v_mount);
1274 if (devfs_populate_vp(ap->a_vp) != 0) {
1275 if (tmp_ncookies != NULL)
1276 ap->a_ncookies = tmp_ncookies;
1277 return (EIO);
1278 }
1279 error = 0;
1280 de = ap->a_vp->v_data;
1281 off = 0;
1282 TAILQ_FOREACH(dd, &de->de_dlist, de_list) {
1283 KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__));
1284 if (dd->de_flags & (DE_COVERED | DE_WHITEOUT))
1285 continue;
1286 if (devfs_prison_check(dd, uio->uio_td))
1287 continue;
1288 if (dd->de_dirent->d_type == DT_DIR)
1289 de = dd->de_dir;
1290 else
1291 de = dd;
1292 dp = dd->de_dirent;
1293 if (dp->d_reclen > uio->uio_resid)
1294 break;
1295 dp->d_fileno = de->de_inode;
1296 if (off >= uio->uio_offset) {
1297 error = vfs_read_dirent(ap, dp, off);
1298 if (error)
1299 break;
1300 }
1301 off += dp->d_reclen;
1302 }
1303 sx_xunlock(&dmp->dm_lock);
1304 uio->uio_offset = off;
1305
1306 /*
1307 * Restore ap->a_ncookies if it wasn't originally NULL in the first
1308 * place.
1309 */
1310 if (tmp_ncookies != NULL)
1311 ap->a_ncookies = tmp_ncookies;
1312
1313 return (error);
1314 }
1315
1316 static int
1317 devfs_readlink(struct vop_readlink_args *ap)
1318 {
1319 struct devfs_dirent *de;
1320
1321 de = ap->a_vp->v_data;
1322 return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio));
1323 }
1324
1325 static int
1326 devfs_reclaim(struct vop_reclaim_args *ap)
1327 {
1328 struct vnode *vp;
1329 struct devfs_dirent *de;
1330
1331 vp = ap->a_vp;
1332 mtx_lock(&devfs_de_interlock);
1333 de = vp->v_data;
1334 if (de != NULL) {
1335 de->de_vnode = NULL;
1336 vp->v_data = NULL;
1337 }
1338 mtx_unlock(&devfs_de_interlock);
1339 vnode_destroy_vobject(vp);
1340 return (0);
1341 }
1342
1343 static int
1344 devfs_reclaim_vchr(struct vop_reclaim_args *ap)
1345 {
1346 struct vnode *vp;
1347 struct cdev *dev;
1348
1349 vp = ap->a_vp;
1350 MPASS(vp->v_type == VCHR);
1351
1352 devfs_reclaim(ap);
1353
1354 VI_LOCK(vp);
1355 dev_lock();
1356 dev = vp->v_rdev;
1357 vp->v_rdev = NULL;
1358 if (dev != NULL)
1359 dev->si_usecount -= vp->v_usecount;
1360 dev_unlock();
1361 VI_UNLOCK(vp);
1362 if (dev != NULL)
1363 dev_rel(dev);
1364 return (0);
1365 }
1366
1367 static int
1368 devfs_remove(struct vop_remove_args *ap)
1369 {
1370 struct vnode *dvp = ap->a_dvp;
1371 struct vnode *vp = ap->a_vp;
1372 struct devfs_dirent *dd;
1373 struct devfs_dirent *de, *de_covered;
1374 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount);
1375
1376 ASSERT_VOP_ELOCKED(dvp, "devfs_remove");
1377 ASSERT_VOP_ELOCKED(vp, "devfs_remove");
1378
1379 sx_xlock(&dmp->dm_lock);
1380 dd = ap->a_dvp->v_data;
1381 de = vp->v_data;
1382 if (de->de_cdp == NULL) {
1383 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
1384 if (de->de_dirent->d_type == DT_LNK) {
1385 de_covered = devfs_find(dd, de->de_dirent->d_name,
1386 de->de_dirent->d_namlen, 0);
1387 if (de_covered != NULL)
1388 de_covered->de_flags &= ~DE_COVERED;
1389 }
1390 /* We need to unlock dvp because devfs_delete() may lock it. */
1391 VOP_UNLOCK(vp, 0);
1392 if (dvp != vp)
1393 VOP_UNLOCK(dvp, 0);
1394 devfs_delete(dmp, de, 0);
1395 sx_xunlock(&dmp->dm_lock);
1396 if (dvp != vp)
1397 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
1398 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1399 } else {
1400 de->de_flags |= DE_WHITEOUT;
1401 sx_xunlock(&dmp->dm_lock);
1402 }
1403 return (0);
1404 }
1405
1406 /*
1407 * Revoke is called on a tty when a terminal session ends. The vnode
1408 * is orphaned by setting v_op to deadfs so we need to let go of it
1409 * as well so that we create a new one next time around.
1410 *
1411 */
1412 static int
1413 devfs_revoke(struct vop_revoke_args *ap)
1414 {
1415 struct vnode *vp = ap->a_vp, *vp2;
1416 struct cdev *dev;
1417 struct cdev_priv *cdp;
1418 struct devfs_dirent *de;
1419 u_int i;
1420
1421 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL"));
1422
1423 dev = vp->v_rdev;
1424 cdp = cdev2priv(dev);
1425
1426 dev_lock();
1427 cdp->cdp_inuse++;
1428 dev_unlock();
1429
1430 vhold(vp);
1431 vgone(vp);
1432 vdrop(vp);
1433
1434 VOP_UNLOCK(vp,0);
1435 loop:
1436 for (;;) {
1437 mtx_lock(&devfs_de_interlock);
1438 dev_lock();
1439 vp2 = NULL;
1440 for (i = 0; i <= cdp->cdp_maxdirent; i++) {
1441 de = cdp->cdp_dirents[i];
1442 if (de == NULL)
1443 continue;
1444
1445 vp2 = de->de_vnode;
1446 if (vp2 != NULL) {
1447 dev_unlock();
1448 VI_LOCK(vp2);
1449 mtx_unlock(&devfs_de_interlock);
1450 if (vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK,
1451 curthread))
1452 goto loop;
1453 vhold(vp2);
1454 vgone(vp2);
1455 vdrop(vp2);
1456 vput(vp2);
1457 break;
1458 }
1459 }
1460 if (vp2 != NULL) {
1461 continue;
1462 }
1463 dev_unlock();
1464 mtx_unlock(&devfs_de_interlock);
1465 break;
1466 }
1467 dev_lock();
1468 cdp->cdp_inuse--;
1469 if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) {
1470 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
1471 dev_unlock();
1472 dev_rel(&cdp->cdp_c);
1473 } else
1474 dev_unlock();
1475
1476 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1477 return (0);
1478 }
1479
1480 static int
1481 devfs_rioctl(struct vop_ioctl_args *ap)
1482 {
1483 struct vnode *vp;
1484 struct devfs_mount *dmp;
1485 int error;
1486
1487 vp = ap->a_vp;
1488 vn_lock(vp, LK_SHARED | LK_RETRY);
1489 if (vp->v_iflag & VI_DOOMED) {
1490 VOP_UNLOCK(vp, 0);
1491 return (EBADF);
1492 }
1493 dmp = VFSTODEVFS(vp->v_mount);
1494 sx_xlock(&dmp->dm_lock);
1495 VOP_UNLOCK(vp, 0);
1496 DEVFS_DMP_HOLD(dmp);
1497 devfs_populate(dmp);
1498 if (DEVFS_DMP_DROP(dmp)) {
1499 sx_xunlock(&dmp->dm_lock);
1500 devfs_unmount_final(dmp);
1501 return (ENOENT);
1502 }
1503 error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td);
1504 sx_xunlock(&dmp->dm_lock);
1505 return (error);
1506 }
1507
1508 static int
1509 devfs_rread(struct vop_read_args *ap)
1510 {
1511
1512 if (ap->a_vp->v_type != VDIR)
1513 return (EINVAL);
1514 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL));
1515 }
1516
1517 static int
1518 devfs_setattr(struct vop_setattr_args *ap)
1519 {
1520 struct devfs_dirent *de;
1521 struct vattr *vap;
1522 struct vnode *vp;
1523 struct thread *td;
1524 int c, error;
1525 uid_t uid;
1526 gid_t gid;
1527
1528 vap = ap->a_vap;
1529 vp = ap->a_vp;
1530 td = curthread;
1531 if ((vap->va_type != VNON) ||
1532 (vap->va_nlink != VNOVAL) ||
1533 (vap->va_fsid != VNOVAL) ||
1534 (vap->va_fileid != VNOVAL) ||
1535 (vap->va_blocksize != VNOVAL) ||
1536 (vap->va_flags != VNOVAL && vap->va_flags != 0) ||
1537 (vap->va_rdev != VNOVAL) ||
1538 ((int)vap->va_bytes != VNOVAL) ||
1539 (vap->va_gen != VNOVAL)) {
1540 return (EINVAL);
1541 }
1542
1543 error = devfs_populate_vp(vp);
1544 if (error != 0)
1545 return (error);
1546
1547 de = vp->v_data;
1548 if (vp->v_type == VDIR)
1549 de = de->de_dir;
1550
1551 c = 0;
1552 if (vap->va_uid == (uid_t)VNOVAL)
1553 uid = de->de_uid;
1554 else
1555 uid = vap->va_uid;
1556 if (vap->va_gid == (gid_t)VNOVAL)
1557 gid = de->de_gid;
1558 else
1559 gid = vap->va_gid;
1560 if (uid != de->de_uid || gid != de->de_gid) {
1561 if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid ||
1562 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) {
1563 error = priv_check(td, PRIV_VFS_CHOWN);
1564 if (error != 0)
1565 goto ret;
1566 }
1567 de->de_uid = uid;
1568 de->de_gid = gid;
1569 c = 1;
1570 }
1571
1572 if (vap->va_mode != (mode_t)VNOVAL) {
1573 if (ap->a_cred->cr_uid != de->de_uid) {
1574 error = priv_check(td, PRIV_VFS_ADMIN);
1575 if (error != 0)
1576 goto ret;
1577 }
1578 de->de_mode = vap->va_mode;
1579 c = 1;
1580 }
1581
1582 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1583 error = vn_utimes_perm(vp, vap, ap->a_cred, td);
1584 if (error != 0)
1585 goto ret;
1586 if (vap->va_atime.tv_sec != VNOVAL) {
1587 if (vp->v_type == VCHR)
1588 vp->v_rdev->si_atime = vap->va_atime;
1589 else
1590 de->de_atime = vap->va_atime;
1591 }
1592 if (vap->va_mtime.tv_sec != VNOVAL) {
1593 if (vp->v_type == VCHR)
1594 vp->v_rdev->si_mtime = vap->va_mtime;
1595 else
1596 de->de_mtime = vap->va_mtime;
1597 }
1598 c = 1;
1599 }
1600
1601 if (c) {
1602 if (vp->v_type == VCHR)
1603 vfs_timestamp(&vp->v_rdev->si_ctime);
1604 else
1605 vfs_timestamp(&de->de_mtime);
1606 }
1607
1608 ret:
1609 sx_xunlock(&VFSTODEVFS(vp->v_mount)->dm_lock);
1610 return (error);
1611 }
1612
1613 #ifdef MAC
1614 static int
1615 devfs_setlabel(struct vop_setlabel_args *ap)
1616 {
1617 struct vnode *vp;
1618 struct devfs_dirent *de;
1619
1620 vp = ap->a_vp;
1621 de = vp->v_data;
1622
1623 mac_vnode_relabel(ap->a_cred, vp, ap->a_label);
1624 mac_devfs_update(vp->v_mount, de, vp);
1625
1626 return (0);
1627 }
1628 #endif
1629
1630 static int
1631 devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td)
1632 {
1633
1634 return (vnops.fo_stat(fp, sb, cred, td));
1635 }
1636
1637 static int
1638 devfs_symlink(struct vop_symlink_args *ap)
1639 {
1640 int i, error;
1641 struct devfs_dirent *dd;
1642 struct devfs_dirent *de, *de_covered, *de_dotdot;
1643 struct devfs_mount *dmp;
1644
1645 error = priv_check(curthread, PRIV_DEVFS_SYMLINK);
1646 if (error)
1647 return(error);
1648 dmp = VFSTODEVFS(ap->a_dvp->v_mount);
1649 if (devfs_populate_vp(ap->a_dvp) != 0)
1650 return (ENOENT);
1651
1652 dd = ap->a_dvp->v_data;
1653 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen);
1654 de->de_flags = DE_USER;
1655 de->de_uid = 0;
1656 de->de_gid = 0;
1657 de->de_mode = 0755;
1658 de->de_inode = alloc_unr(devfs_inos);
1659 de->de_dir = dd;
1660 de->de_dirent->d_type = DT_LNK;
1661 i = strlen(ap->a_target) + 1;
1662 de->de_symlink = malloc(i, M_DEVFS, M_WAITOK);
1663 bcopy(ap->a_target, de->de_symlink, i);
1664 #ifdef MAC
1665 mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de);
1666 #endif
1667 de_covered = devfs_find(dd, de->de_dirent->d_name,
1668 de->de_dirent->d_namlen, 0);
1669 if (de_covered != NULL) {
1670 if ((de_covered->de_flags & DE_USER) != 0) {
1671 devfs_delete(dmp, de, DEVFS_DEL_NORECURSE);
1672 sx_xunlock(&dmp->dm_lock);
1673 return (EEXIST);
1674 }
1675 KASSERT((de_covered->de_flags & DE_COVERED) == 0,
1676 ("devfs_symlink: entry %p already covered", de_covered));
1677 de_covered->de_flags |= DE_COVERED;
1678 }
1679
1680 de_dotdot = TAILQ_FIRST(&dd->de_dlist); /* "." */
1681 de_dotdot = TAILQ_NEXT(de_dotdot, de_list); /* ".." */
1682 TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list);
1683 devfs_dir_ref_de(dmp, dd);
1684 devfs_rules_apply(dmp, de);
1685
1686 return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp));
1687 }
1688
1689 static int
1690 devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td)
1691 {
1692
1693 return (vnops.fo_truncate(fp, length, cred, td));
1694 }
1695
1696 static int
1697 devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred,
1698 int flags, struct thread *td)
1699 {
1700 struct cdev *dev;
1701 int error, ioflag, ref;
1702 ssize_t resid;
1703 struct cdevsw *dsw;
1704 struct file *fpop;
1705
1706 if (uio->uio_resid > DEVFS_IOSIZE_MAX)
1707 return (EINVAL);
1708 fpop = td->td_fpop;
1709 error = devfs_fp_check(fp, &dev, &dsw, &ref);
1710 if (error != 0) {
1711 error = vnops.fo_write(fp, uio, cred, flags, td);
1712 return (error);
1713 }
1714 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td));
1715 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC);
1716 if (ioflag & O_DIRECT)
1717 ioflag |= IO_DIRECT;
1718 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK);
1719
1720 resid = uio->uio_resid;
1721
1722 error = dsw->d_write(dev, uio, ioflag);
1723 if (uio->uio_resid != resid || (error == 0 && resid != 0)) {
1724 devfs_timestamp(&dev->si_ctime);
1725 dev->si_mtime = dev->si_ctime;
1726 }
1727 td->td_fpop = fpop;
1728 dev_relthread(dev, ref);
1729
1730 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF);
1731 return (error);
1732 }
1733
1734 dev_t
1735 dev2udev(struct cdev *x)
1736 {
1737 if (x == NULL)
1738 return (NODEV);
1739 return (cdev2priv(x)->cdp_inode);
1740 }
1741
1742 static struct fileops devfs_ops_f = {
1743 .fo_read = devfs_read_f,
1744 .fo_write = devfs_write_f,
1745 .fo_truncate = devfs_truncate_f,
1746 .fo_ioctl = devfs_ioctl_f,
1747 .fo_poll = devfs_poll_f,
1748 .fo_kqfilter = devfs_kqfilter_f,
1749 .fo_stat = devfs_stat_f,
1750 .fo_close = devfs_close_f,
1751 .fo_chmod = vn_chmod,
1752 .fo_chown = vn_chown,
1753 .fo_sendfile = vn_sendfile,
1754 .fo_seek = vn_seek,
1755 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
1756 };
1757
1758 static struct vop_vector devfs_vnodeops = {
1759 .vop_default = &default_vnodeops,
1760
1761 .vop_access = devfs_access,
1762 .vop_getattr = devfs_getattr,
1763 .vop_ioctl = devfs_rioctl,
1764 .vop_lookup = devfs_lookup,
1765 .vop_mknod = devfs_mknod,
1766 .vop_pathconf = devfs_pathconf,
1767 .vop_read = devfs_rread,
1768 .vop_readdir = devfs_readdir,
1769 .vop_readlink = devfs_readlink,
1770 .vop_reclaim = devfs_reclaim,
1771 .vop_remove = devfs_remove,
1772 .vop_revoke = devfs_revoke,
1773 .vop_setattr = devfs_setattr,
1774 #ifdef MAC
1775 .vop_setlabel = devfs_setlabel,
1776 #endif
1777 .vop_symlink = devfs_symlink,
1778 .vop_vptocnp = devfs_vptocnp,
1779 };
1780
1781 static struct vop_vector devfs_specops = {
1782 .vop_default = &default_vnodeops,
1783
1784 .vop_access = devfs_access,
1785 .vop_bmap = VOP_PANIC,
1786 .vop_close = devfs_close,
1787 .vop_create = VOP_PANIC,
1788 .vop_fsync = devfs_fsync,
1789 .vop_getattr = devfs_getattr,
1790 .vop_link = VOP_PANIC,
1791 .vop_mkdir = VOP_PANIC,
1792 .vop_mknod = VOP_PANIC,
1793 .vop_open = devfs_open,
1794 .vop_pathconf = devfs_pathconf,
1795 .vop_poll = dead_poll,
1796 .vop_print = devfs_print,
1797 .vop_read = dead_read,
1798 .vop_readdir = VOP_PANIC,
1799 .vop_readlink = VOP_PANIC,
1800 .vop_reallocblks = VOP_PANIC,
1801 .vop_reclaim = devfs_reclaim_vchr,
1802 .vop_remove = devfs_remove,
1803 .vop_rename = VOP_PANIC,
1804 .vop_revoke = devfs_revoke,
1805 .vop_rmdir = VOP_PANIC,
1806 .vop_setattr = devfs_setattr,
1807 #ifdef MAC
1808 .vop_setlabel = devfs_setlabel,
1809 #endif
1810 .vop_strategy = VOP_PANIC,
1811 .vop_symlink = VOP_PANIC,
1812 .vop_vptocnp = devfs_vptocnp,
1813 .vop_write = dead_write,
1814 };
1815
1816 /*
1817 * Our calling convention to the device drivers used to be that we passed
1818 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_
1819 * flags instead since that's what open(), close() and ioctl() takes and
1820 * we don't really want vnode.h in device drivers.
1821 * We solved the source compatibility by redefining some vnode flags to
1822 * be the same as the fcntl ones and by sending down the bitwise OR of
1823 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody
1824 * pulls the rug out under this.
1825 */
1826 CTASSERT(O_NONBLOCK == IO_NDELAY);
1827 CTASSERT(O_FSYNC == IO_SYNC);
Cache object: ee3c33ef55f41073e6e3dfa543c4ffce
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