1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2000,2004
5 * Poul-Henning Kamp. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Neither the name of the University nor the names of its contributors
13 * may be used to endorse or promote products derived from this software
14 * without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36
29 *
30 * $FreeBSD: releng/12.0/sys/fs/devfs/devfs_devs.c 341085 2018-11-27 17:58:25Z markj $
31 */
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/conf.h>
36 #include <sys/dirent.h>
37 #include <sys/kernel.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/proc.h>
42 #include <sys/sx.h>
43 #include <sys/sysctl.h>
44 #include <sys/vnode.h>
45
46 #include <sys/kdb.h>
47
48 #include <fs/devfs/devfs.h>
49 #include <fs/devfs/devfs_int.h>
50
51 #include <security/mac/mac_framework.h>
52
53 /*
54 * The one true (but secret) list of active devices in the system.
55 * Locked by dev_lock()/devmtx
56 */
57 struct cdev_priv_list cdevp_list = TAILQ_HEAD_INITIALIZER(cdevp_list);
58
59 struct unrhdr *devfs_inos;
60
61
62 static MALLOC_DEFINE(M_DEVFS2, "DEVFS2", "DEVFS data 2");
63 static MALLOC_DEFINE(M_DEVFS3, "DEVFS3", "DEVFS data 3");
64 static MALLOC_DEFINE(M_CDEVP, "DEVFS1", "DEVFS cdev_priv storage");
65
66 SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "DEVFS filesystem");
67
68 static unsigned devfs_generation;
69 SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD,
70 &devfs_generation, 0, "DEVFS generation number");
71
72 unsigned devfs_rule_depth = 1;
73 SYSCTL_UINT(_vfs_devfs, OID_AUTO, rule_depth, CTLFLAG_RW,
74 &devfs_rule_depth, 0, "Max depth of ruleset include");
75
76 /*
77 * Helper sysctl for devname(3). We're given a dev_t and return the
78 * name, if any, registered by the device driver.
79 */
80 static int
81 sysctl_devname(SYSCTL_HANDLER_ARGS)
82 {
83 int error;
84 dev_t ud;
85 #ifdef COMPAT_FREEBSD11
86 uint32_t ud_compat;
87 #endif
88 struct cdev_priv *cdp;
89 struct cdev *dev;
90
91 #ifdef COMPAT_FREEBSD11
92 if (req->newlen == sizeof(ud_compat)) {
93 error = SYSCTL_IN(req, &ud_compat, sizeof(ud_compat));
94 if (error == 0)
95 ud = ud_compat == (uint32_t)NODEV ? NODEV : ud_compat;
96 } else
97 #endif
98 error = SYSCTL_IN(req, &ud, sizeof (ud));
99 if (error)
100 return (error);
101 if (ud == NODEV)
102 return (EINVAL);
103 dev = NULL;
104 dev_lock();
105 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list)
106 if (cdp->cdp_inode == ud) {
107 dev = &cdp->cdp_c;
108 dev_refl(dev);
109 break;
110 }
111 dev_unlock();
112 if (dev == NULL)
113 return (ENOENT);
114 error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1);
115 dev_rel(dev);
116 return (error);
117 }
118
119 SYSCTL_PROC(_kern, OID_AUTO, devname,
120 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE,
121 NULL, 0, sysctl_devname, "", "devname(3) handler");
122
123 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
124 SYSCTL_NULL_INT_PTR, sizeof(struct cdev), "sizeof(struct cdev)");
125
126 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev_priv, CTLFLAG_RD,
127 SYSCTL_NULL_INT_PTR, sizeof(struct cdev_priv), "sizeof(struct cdev_priv)");
128
129 struct cdev *
130 devfs_alloc(int flags)
131 {
132 struct cdev_priv *cdp;
133 struct cdev *cdev;
134 struct timespec ts;
135
136 cdp = malloc(sizeof *cdp, M_CDEVP, M_ZERO |
137 ((flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK));
138 if (cdp == NULL)
139 return (NULL);
140
141 cdp->cdp_dirents = &cdp->cdp_dirent0;
142
143 cdev = &cdp->cdp_c;
144 LIST_INIT(&cdev->si_children);
145 vfs_timestamp(&ts);
146 cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts;
147
148 return (cdev);
149 }
150
151 int
152 devfs_dev_exists(const char *name)
153 {
154 struct cdev_priv *cdp;
155
156 mtx_assert(&devmtx, MA_OWNED);
157
158 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
159 if ((cdp->cdp_flags & CDP_ACTIVE) == 0)
160 continue;
161 if (devfs_pathpath(cdp->cdp_c.si_name, name) != 0)
162 return (1);
163 if (devfs_pathpath(name, cdp->cdp_c.si_name) != 0)
164 return (1);
165 }
166 if (devfs_dir_find(name) != 0)
167 return (1);
168
169 return (0);
170 }
171
172 void
173 devfs_free(struct cdev *cdev)
174 {
175 struct cdev_priv *cdp;
176
177 cdp = cdev2priv(cdev);
178 if (cdev->si_cred != NULL)
179 crfree(cdev->si_cred);
180 devfs_free_cdp_inode(cdp->cdp_inode);
181 if (cdp->cdp_maxdirent > 0)
182 free(cdp->cdp_dirents, M_DEVFS2);
183 free(cdp, M_CDEVP);
184 }
185
186 struct devfs_dirent *
187 devfs_find(struct devfs_dirent *dd, const char *name, int namelen, int type)
188 {
189 struct devfs_dirent *de;
190
191 TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
192 if (namelen != de->de_dirent->d_namlen)
193 continue;
194 if (type != 0 && type != de->de_dirent->d_type)
195 continue;
196
197 /*
198 * The race with finding non-active name is not
199 * completely closed by the check, but it is similar
200 * to the devfs_allocv() in making it unlikely enough.
201 */
202 if (de->de_dirent->d_type == DT_CHR &&
203 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0)
204 continue;
205
206 if (bcmp(name, de->de_dirent->d_name, namelen) != 0)
207 continue;
208 break;
209 }
210 KASSERT(de == NULL || (de->de_flags & DE_DOOMED) == 0,
211 ("devfs_find: returning a doomed entry"));
212 return (de);
213 }
214
215 struct devfs_dirent *
216 devfs_newdirent(char *name, int namelen)
217 {
218 int i;
219 struct devfs_dirent *de;
220 struct dirent d;
221
222 d.d_namlen = namelen;
223 i = sizeof(*de) + GENERIC_DIRSIZ(&d);
224 de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO);
225 de->de_dirent = (struct dirent *)(de + 1);
226 de->de_dirent->d_namlen = namelen;
227 de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
228 bcopy(name, de->de_dirent->d_name, namelen);
229 dirent_terminate(de->de_dirent);
230 vfs_timestamp(&de->de_ctime);
231 de->de_mtime = de->de_atime = de->de_ctime;
232 de->de_links = 1;
233 de->de_holdcnt = 1;
234 #ifdef MAC
235 mac_devfs_init(de);
236 #endif
237 return (de);
238 }
239
240 struct devfs_dirent *
241 devfs_parent_dirent(struct devfs_dirent *de)
242 {
243
244 if (de->de_dirent->d_type != DT_DIR)
245 return (de->de_dir);
246
247 if (de->de_flags & (DE_DOT | DE_DOTDOT))
248 return (NULL);
249
250 de = TAILQ_FIRST(&de->de_dlist); /* "." */
251 if (de == NULL)
252 return (NULL);
253 de = TAILQ_NEXT(de, de_list); /* ".." */
254 if (de == NULL)
255 return (NULL);
256
257 return (de->de_dir);
258 }
259
260 struct devfs_dirent *
261 devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen,
262 struct devfs_dirent *dotdot, u_int inode)
263 {
264 struct devfs_dirent *dd;
265 struct devfs_dirent *de;
266
267 /* Create the new directory */
268 dd = devfs_newdirent(name, namelen);
269 TAILQ_INIT(&dd->de_dlist);
270 dd->de_dirent->d_type = DT_DIR;
271 dd->de_mode = 0555;
272 dd->de_links = 2;
273 dd->de_dir = dd;
274 if (inode != 0)
275 dd->de_inode = inode;
276 else
277 dd->de_inode = alloc_unr(devfs_inos);
278
279 /*
280 * "." and ".." are always the two first entries in the
281 * de_dlist list.
282 *
283 * Create the "." entry in the new directory.
284 */
285 de = devfs_newdirent(".", 1);
286 de->de_dirent->d_type = DT_DIR;
287 de->de_flags |= DE_DOT;
288 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
289 de->de_dir = dd;
290
291 /* Create the ".." entry in the new directory. */
292 de = devfs_newdirent("..", 2);
293 de->de_dirent->d_type = DT_DIR;
294 de->de_flags |= DE_DOTDOT;
295 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
296 if (dotdot == NULL) {
297 de->de_dir = dd;
298 } else {
299 de->de_dir = dotdot;
300 sx_assert(&dmp->dm_lock, SX_XLOCKED);
301 TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list);
302 dotdot->de_links++;
303 devfs_rules_apply(dmp, dd);
304 }
305
306 #ifdef MAC
307 mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd);
308 #endif
309 return (dd);
310 }
311
312 void
313 devfs_dirent_free(struct devfs_dirent *de)
314 {
315 struct vnode *vp;
316
317 vp = de->de_vnode;
318 mtx_lock(&devfs_de_interlock);
319 if (vp != NULL && vp->v_data == de)
320 vp->v_data = NULL;
321 mtx_unlock(&devfs_de_interlock);
322 free(de, M_DEVFS3);
323 }
324
325 /*
326 * Removes a directory if it is empty. Also empty parent directories are
327 * removed recursively.
328 */
329 static void
330 devfs_rmdir_empty(struct devfs_mount *dm, struct devfs_dirent *de)
331 {
332 struct devfs_dirent *dd, *de_dot, *de_dotdot;
333
334 sx_assert(&dm->dm_lock, SX_XLOCKED);
335
336 for (;;) {
337 KASSERT(de->de_dirent->d_type == DT_DIR,
338 ("devfs_rmdir_empty: de is not a directory"));
339
340 if ((de->de_flags & DE_DOOMED) != 0 || de == dm->dm_rootdir)
341 return;
342
343 de_dot = TAILQ_FIRST(&de->de_dlist);
344 KASSERT(de_dot != NULL, ("devfs_rmdir_empty: . missing"));
345 de_dotdot = TAILQ_NEXT(de_dot, de_list);
346 KASSERT(de_dotdot != NULL, ("devfs_rmdir_empty: .. missing"));
347 /* Return if the directory is not empty. */
348 if (TAILQ_NEXT(de_dotdot, de_list) != NULL)
349 return;
350
351 dd = devfs_parent_dirent(de);
352 KASSERT(dd != NULL, ("devfs_rmdir_empty: NULL dd"));
353 TAILQ_REMOVE(&de->de_dlist, de_dot, de_list);
354 TAILQ_REMOVE(&de->de_dlist, de_dotdot, de_list);
355 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
356 DEVFS_DE_HOLD(dd);
357 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
358 devfs_delete(dm, de_dot, DEVFS_DEL_NORECURSE);
359 devfs_delete(dm, de_dotdot, DEVFS_DEL_NORECURSE);
360 if (DEVFS_DE_DROP(dd)) {
361 devfs_dirent_free(dd);
362 return;
363 }
364
365 de = dd;
366 }
367 }
368
369 /*
370 * The caller needs to hold the dm for the duration of the call since
371 * dm->dm_lock may be temporary dropped.
372 */
373 void
374 devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int flags)
375 {
376 struct devfs_dirent *dd;
377 struct vnode *vp;
378
379 KASSERT((de->de_flags & DE_DOOMED) == 0,
380 ("devfs_delete doomed dirent"));
381 de->de_flags |= DE_DOOMED;
382
383 if ((flags & DEVFS_DEL_NORECURSE) == 0) {
384 dd = devfs_parent_dirent(de);
385 if (dd != NULL)
386 DEVFS_DE_HOLD(dd);
387 if (de->de_flags & DE_USER) {
388 KASSERT(dd != NULL, ("devfs_delete: NULL dd"));
389 devfs_dir_unref_de(dm, dd);
390 }
391 } else
392 dd = NULL;
393
394 mtx_lock(&devfs_de_interlock);
395 vp = de->de_vnode;
396 if (vp != NULL) {
397 VI_LOCK(vp);
398 mtx_unlock(&devfs_de_interlock);
399 vholdl(vp);
400 sx_unlock(&dm->dm_lock);
401 if ((flags & DEVFS_DEL_VNLOCKED) == 0)
402 vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY);
403 else
404 VI_UNLOCK(vp);
405 vgone(vp);
406 if ((flags & DEVFS_DEL_VNLOCKED) == 0)
407 VOP_UNLOCK(vp, 0);
408 vdrop(vp);
409 sx_xlock(&dm->dm_lock);
410 } else
411 mtx_unlock(&devfs_de_interlock);
412 if (de->de_symlink) {
413 free(de->de_symlink, M_DEVFS);
414 de->de_symlink = NULL;
415 }
416 #ifdef MAC
417 mac_devfs_destroy(de);
418 #endif
419 if (de->de_inode > DEVFS_ROOTINO) {
420 devfs_free_cdp_inode(de->de_inode);
421 de->de_inode = 0;
422 }
423 if (DEVFS_DE_DROP(de))
424 devfs_dirent_free(de);
425
426 if (dd != NULL) {
427 if (DEVFS_DE_DROP(dd))
428 devfs_dirent_free(dd);
429 else
430 devfs_rmdir_empty(dm, dd);
431 }
432 }
433
434 /*
435 * Called on unmount.
436 * Recursively removes the entire tree.
437 * The caller needs to hold the dm for the duration of the call.
438 */
439
440 static void
441 devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd)
442 {
443 struct devfs_dirent *de;
444
445 sx_assert(&dm->dm_lock, SX_XLOCKED);
446
447 DEVFS_DE_HOLD(dd);
448 for (;;) {
449 /*
450 * Use TAILQ_LAST() to remove "." and ".." last.
451 * We might need ".." to resolve a path in
452 * devfs_dir_unref_de().
453 */
454 de = TAILQ_LAST(&dd->de_dlist, devfs_dlist_head);
455 if (de == NULL)
456 break;
457 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
458 if (de->de_flags & DE_USER)
459 devfs_dir_unref_de(dm, dd);
460 if (de->de_flags & (DE_DOT | DE_DOTDOT))
461 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
462 else if (de->de_dirent->d_type == DT_DIR)
463 devfs_purge(dm, de);
464 else
465 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
466 }
467 if (DEVFS_DE_DROP(dd))
468 devfs_dirent_free(dd);
469 else if ((dd->de_flags & DE_DOOMED) == 0)
470 devfs_delete(dm, dd, DEVFS_DEL_NORECURSE);
471 }
472
473 /*
474 * Each cdev_priv has an array of pointers to devfs_dirent which is indexed
475 * by the mount points dm_idx.
476 * This function extends the array when necessary, taking into account that
477 * the default array is 1 element and not malloc'ed.
478 */
479 static void
480 devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm)
481 {
482 struct devfs_dirent **dep;
483 int siz;
484
485 siz = (dm->dm_idx + 1) * sizeof *dep;
486 dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO);
487 dev_lock();
488 if (dm->dm_idx <= cdp->cdp_maxdirent) {
489 /* We got raced */
490 dev_unlock();
491 free(dep, M_DEVFS2);
492 return;
493 }
494 memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep);
495 if (cdp->cdp_maxdirent > 0)
496 free(cdp->cdp_dirents, M_DEVFS2);
497 cdp->cdp_dirents = dep;
498 /*
499 * XXX: if malloc told us how much we actually got this could
500 * XXX: be optimized.
501 */
502 cdp->cdp_maxdirent = dm->dm_idx;
503 dev_unlock();
504 }
505
506 /*
507 * The caller needs to hold the dm for the duration of the call.
508 */
509 static int
510 devfs_populate_loop(struct devfs_mount *dm, int cleanup)
511 {
512 struct cdev_priv *cdp;
513 struct devfs_dirent *de;
514 struct devfs_dirent *dd, *dt;
515 struct cdev *pdev;
516 int de_flags, depth, j;
517 char *q, *s;
518
519 sx_assert(&dm->dm_lock, SX_XLOCKED);
520 dev_lock();
521 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
522
523 KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents"));
524
525 /*
526 * If we are unmounting, or the device has been destroyed,
527 * clean up our dirent.
528 */
529 if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) &&
530 dm->dm_idx <= cdp->cdp_maxdirent &&
531 cdp->cdp_dirents[dm->dm_idx] != NULL) {
532 de = cdp->cdp_dirents[dm->dm_idx];
533 cdp->cdp_dirents[dm->dm_idx] = NULL;
534 KASSERT(cdp == de->de_cdp,
535 ("%s %d %s %p %p", __func__, __LINE__,
536 cdp->cdp_c.si_name, cdp, de->de_cdp));
537 KASSERT(de->de_dir != NULL, ("Null de->de_dir"));
538 dev_unlock();
539
540 TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list);
541 de->de_cdp = NULL;
542 de->de_inode = 0;
543 devfs_delete(dm, de, 0);
544 dev_lock();
545 cdp->cdp_inuse--;
546 dev_unlock();
547 return (1);
548 }
549 /*
550 * GC any lingering devices
551 */
552 if (!(cdp->cdp_flags & CDP_ACTIVE)) {
553 if (cdp->cdp_inuse > 0)
554 continue;
555 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
556 dev_unlock();
557 dev_rel(&cdp->cdp_c);
558 return (1);
559 }
560 /*
561 * Don't create any new dirents if we are unmounting
562 */
563 if (cleanup)
564 continue;
565 KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!"));
566
567 if (dm->dm_idx <= cdp->cdp_maxdirent &&
568 cdp->cdp_dirents[dm->dm_idx] != NULL) {
569 de = cdp->cdp_dirents[dm->dm_idx];
570 KASSERT(cdp == de->de_cdp, ("inconsistent cdp"));
571 continue;
572 }
573
574
575 cdp->cdp_inuse++;
576 dev_unlock();
577
578 if (dm->dm_idx > cdp->cdp_maxdirent)
579 devfs_metoo(cdp, dm);
580
581 dd = dm->dm_rootdir;
582 s = cdp->cdp_c.si_name;
583 for (;;) {
584 for (q = s; *q != '/' && *q != '\0'; q++)
585 continue;
586 if (*q != '/')
587 break;
588 de = devfs_find(dd, s, q - s, 0);
589 if (de == NULL)
590 de = devfs_vmkdir(dm, s, q - s, dd, 0);
591 else if (de->de_dirent->d_type == DT_LNK) {
592 de = devfs_find(dd, s, q - s, DT_DIR);
593 if (de == NULL)
594 de = devfs_vmkdir(dm, s, q - s, dd, 0);
595 de->de_flags |= DE_COVERED;
596 }
597 s = q + 1;
598 dd = de;
599 KASSERT(dd->de_dirent->d_type == DT_DIR &&
600 (dd->de_flags & (DE_DOT | DE_DOTDOT)) == 0,
601 ("%s: invalid directory (si_name=%s)",
602 __func__, cdp->cdp_c.si_name));
603
604 }
605 de_flags = 0;
606 de = devfs_find(dd, s, q - s, DT_LNK);
607 if (de != NULL)
608 de_flags |= DE_COVERED;
609
610 de = devfs_newdirent(s, q - s);
611 if (cdp->cdp_c.si_flags & SI_ALIAS) {
612 de->de_uid = 0;
613 de->de_gid = 0;
614 de->de_mode = 0755;
615 de->de_dirent->d_type = DT_LNK;
616 pdev = cdp->cdp_c.si_parent;
617 dt = dd;
618 depth = 0;
619 while (dt != dm->dm_rootdir &&
620 (dt = devfs_parent_dirent(dt)) != NULL)
621 depth++;
622 j = depth * 3 + strlen(pdev->si_name) + 1;
623 de->de_symlink = malloc(j, M_DEVFS, M_WAITOK);
624 de->de_symlink[0] = 0;
625 while (depth-- > 0)
626 strcat(de->de_symlink, "../");
627 strcat(de->de_symlink, pdev->si_name);
628 } else {
629 de->de_uid = cdp->cdp_c.si_uid;
630 de->de_gid = cdp->cdp_c.si_gid;
631 de->de_mode = cdp->cdp_c.si_mode;
632 de->de_dirent->d_type = DT_CHR;
633 }
634 de->de_flags |= de_flags;
635 de->de_inode = cdp->cdp_inode;
636 de->de_cdp = cdp;
637 #ifdef MAC
638 mac_devfs_create_device(cdp->cdp_c.si_cred, dm->dm_mount,
639 &cdp->cdp_c, de);
640 #endif
641 de->de_dir = dd;
642 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
643 devfs_rules_apply(dm, de);
644 dev_lock();
645 /* XXX: could check that cdp is still active here */
646 KASSERT(cdp->cdp_dirents[dm->dm_idx] == NULL,
647 ("%s %d\n", __func__, __LINE__));
648 cdp->cdp_dirents[dm->dm_idx] = de;
649 KASSERT(de->de_cdp != (void *)0xdeadc0de,
650 ("%s %d\n", __func__, __LINE__));
651 dev_unlock();
652 return (1);
653 }
654 dev_unlock();
655 return (0);
656 }
657
658 /*
659 * The caller needs to hold the dm for the duration of the call.
660 */
661 void
662 devfs_populate(struct devfs_mount *dm)
663 {
664 unsigned gen;
665
666 sx_assert(&dm->dm_lock, SX_XLOCKED);
667 gen = devfs_generation;
668 if (dm->dm_generation == gen)
669 return;
670 while (devfs_populate_loop(dm, 0))
671 continue;
672 dm->dm_generation = gen;
673 }
674
675 /*
676 * The caller needs to hold the dm for the duration of the call.
677 */
678 void
679 devfs_cleanup(struct devfs_mount *dm)
680 {
681
682 sx_assert(&dm->dm_lock, SX_XLOCKED);
683 while (devfs_populate_loop(dm, 1))
684 continue;
685 devfs_purge(dm, dm->dm_rootdir);
686 }
687
688 /*
689 * devfs_create() and devfs_destroy() are called from kern_conf.c and
690 * in both cases the devlock() mutex is held, so no further locking
691 * is necessary and no sleeping allowed.
692 */
693
694 void
695 devfs_create(struct cdev *dev)
696 {
697 struct cdev_priv *cdp;
698
699 mtx_assert(&devmtx, MA_OWNED);
700 cdp = cdev2priv(dev);
701 cdp->cdp_flags |= CDP_ACTIVE;
702 cdp->cdp_inode = alloc_unrl(devfs_inos);
703 dev_refl(dev);
704 TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list);
705 devfs_generation++;
706 }
707
708 void
709 devfs_destroy(struct cdev *dev)
710 {
711 struct cdev_priv *cdp;
712
713 mtx_assert(&devmtx, MA_OWNED);
714 cdp = cdev2priv(dev);
715 cdp->cdp_flags &= ~CDP_ACTIVE;
716 devfs_generation++;
717 }
718
719 ino_t
720 devfs_alloc_cdp_inode(void)
721 {
722
723 return (alloc_unr(devfs_inos));
724 }
725
726 void
727 devfs_free_cdp_inode(ino_t ino)
728 {
729
730 if (ino > 0)
731 free_unr(devfs_inos, ino);
732 }
733
734 static void
735 devfs_devs_init(void *junk __unused)
736 {
737
738 devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx);
739 }
740
741 SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL);
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