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 * $FreeBSD$
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 static MALLOC_DEFINE(M_DEVFS2, "DEVFS2", "DEVFS data 2");
62 static MALLOC_DEFINE(M_DEVFS3, "DEVFS3", "DEVFS data 3");
63 static MALLOC_DEFINE(M_CDEVP, "DEVFS1", "DEVFS cdev_priv storage");
64
65 SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
66 "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 mtx_init(&cdp->cdp_threadlock, "devthrd", NULL, MTX_DEF);
142
143 cdp->cdp_dirents = &cdp->cdp_dirent0;
144
145 cdev = &cdp->cdp_c;
146 LIST_INIT(&cdev->si_children);
147 vfs_timestamp(&ts);
148 cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts;
149
150 return (cdev);
151 }
152
153 int
154 devfs_dev_exists(const char *name)
155 {
156 struct cdev_priv *cdp;
157
158 dev_lock_assert_locked();
159
160 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
161 if ((cdp->cdp_flags & CDP_ACTIVE) == 0)
162 continue;
163 if (devfs_pathpath(cdp->cdp_c.si_name, name) != 0)
164 return (1);
165 if (devfs_pathpath(name, cdp->cdp_c.si_name) != 0)
166 return (1);
167 }
168 if (devfs_dir_find(name) != 0)
169 return (1);
170
171 return (0);
172 }
173
174 void
175 devfs_free(struct cdev *cdev)
176 {
177 struct cdev_priv *cdp;
178
179 cdp = cdev2priv(cdev);
180 if (cdev->si_cred != NULL)
181 crfree(cdev->si_cred);
182 devfs_free_cdp_inode(cdp->cdp_inode);
183 if (cdp->cdp_maxdirent > 0)
184 free(cdp->cdp_dirents, M_DEVFS2);
185 mtx_destroy(&cdp->cdp_threadlock);
186 free(cdp, M_CDEVP);
187 }
188
189 struct devfs_dirent *
190 devfs_find(struct devfs_dirent *dd, const char *name, int namelen, int type)
191 {
192 struct devfs_dirent *de;
193
194 TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
195 if (namelen != de->de_dirent->d_namlen)
196 continue;
197 if (type != 0 && type != de->de_dirent->d_type)
198 continue;
199
200 /*
201 * The race with finding non-active name is not
202 * completely closed by the check, but it is similar
203 * to the devfs_allocv() in making it unlikely enough.
204 */
205 if (de->de_dirent->d_type == DT_CHR &&
206 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0)
207 continue;
208
209 if (bcmp(name, de->de_dirent->d_name, namelen) != 0)
210 continue;
211 break;
212 }
213 KASSERT(de == NULL || (de->de_flags & DE_DOOMED) == 0,
214 ("devfs_find: returning a doomed entry"));
215 return (de);
216 }
217
218 struct devfs_dirent *
219 devfs_newdirent(char *name, int namelen)
220 {
221 int i;
222 struct devfs_dirent *de;
223 struct dirent d;
224
225 d.d_namlen = namelen;
226 i = sizeof(*de) + GENERIC_DIRSIZ(&d);
227 de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO);
228 de->de_dirent = (struct dirent *)(de + 1);
229 de->de_dirent->d_namlen = namelen;
230 de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
231 bcopy(name, de->de_dirent->d_name, namelen);
232 dirent_terminate(de->de_dirent);
233 vfs_timestamp(&de->de_ctime);
234 de->de_mtime = de->de_atime = de->de_ctime;
235 de->de_links = 1;
236 de->de_holdcnt = 1;
237 #ifdef MAC
238 mac_devfs_init(de);
239 #endif
240 return (de);
241 }
242
243 struct devfs_dirent *
244 devfs_parent_dirent(struct devfs_dirent *de)
245 {
246
247 if (de->de_dirent->d_type != DT_DIR)
248 return (de->de_dir);
249
250 if (de->de_flags & (DE_DOT | DE_DOTDOT))
251 return (NULL);
252
253 de = TAILQ_FIRST(&de->de_dlist); /* "." */
254 if (de == NULL)
255 return (NULL);
256 de = TAILQ_NEXT(de, de_list); /* ".." */
257 if (de == NULL)
258 return (NULL);
259
260 return (de->de_dir);
261 }
262
263 struct devfs_dirent *
264 devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen,
265 struct devfs_dirent *dotdot, u_int inode)
266 {
267 struct devfs_dirent *dd;
268 struct devfs_dirent *de;
269
270 /* Create the new directory */
271 dd = devfs_newdirent(name, namelen);
272 TAILQ_INIT(&dd->de_dlist);
273 dd->de_dirent->d_type = DT_DIR;
274 dd->de_mode = 0555;
275 dd->de_links = 2;
276 dd->de_dir = dd;
277 if (inode != 0)
278 dd->de_inode = inode;
279 else
280 dd->de_inode = alloc_unr(devfs_inos);
281
282 /*
283 * "." and ".." are always the two first entries in the
284 * de_dlist list.
285 *
286 * Create the "." entry in the new directory.
287 */
288 de = devfs_newdirent(".", 1);
289 de->de_dirent->d_type = DT_DIR;
290 de->de_flags |= DE_DOT;
291 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
292 de->de_dir = dd;
293
294 /* Create the ".." entry in the new directory. */
295 de = devfs_newdirent("..", 2);
296 de->de_dirent->d_type = DT_DIR;
297 de->de_flags |= DE_DOTDOT;
298 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
299 if (dotdot == NULL) {
300 de->de_dir = dd;
301 } else {
302 de->de_dir = dotdot;
303 sx_assert(&dmp->dm_lock, SX_XLOCKED);
304 TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list);
305 dotdot->de_links++;
306 devfs_rules_apply(dmp, dd);
307 }
308
309 #ifdef MAC
310 mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd);
311 #endif
312 return (dd);
313 }
314
315 void
316 devfs_dirent_free(struct devfs_dirent *de)
317 {
318 struct vnode *vp;
319
320 vp = de->de_vnode;
321 mtx_lock(&devfs_de_interlock);
322 if (vp != NULL && vp->v_data == de)
323 vp->v_data = NULL;
324 mtx_unlock(&devfs_de_interlock);
325 free(de, M_DEVFS3);
326 }
327
328 /*
329 * Removes a directory if it is empty. Also empty parent directories are
330 * removed recursively.
331 */
332 static void
333 devfs_rmdir_empty(struct devfs_mount *dm, struct devfs_dirent *de)
334 {
335 struct devfs_dirent *dd, *de_dot, *de_dotdot;
336
337 sx_assert(&dm->dm_lock, SX_XLOCKED);
338
339 for (;;) {
340 KASSERT(de->de_dirent->d_type == DT_DIR,
341 ("devfs_rmdir_empty: de is not a directory"));
342
343 if ((de->de_flags & DE_DOOMED) != 0 || de == dm->dm_rootdir)
344 return;
345
346 de_dot = TAILQ_FIRST(&de->de_dlist);
347 KASSERT(de_dot != NULL, ("devfs_rmdir_empty: . missing"));
348 de_dotdot = TAILQ_NEXT(de_dot, de_list);
349 KASSERT(de_dotdot != NULL, ("devfs_rmdir_empty: .. missing"));
350 /* Return if the directory is not empty. */
351 if (TAILQ_NEXT(de_dotdot, de_list) != NULL)
352 return;
353
354 dd = devfs_parent_dirent(de);
355 KASSERT(dd != NULL, ("devfs_rmdir_empty: NULL dd"));
356 TAILQ_REMOVE(&de->de_dlist, de_dot, de_list);
357 TAILQ_REMOVE(&de->de_dlist, de_dotdot, de_list);
358 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
359 DEVFS_DE_HOLD(dd);
360 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
361 devfs_delete(dm, de_dot, DEVFS_DEL_NORECURSE);
362 devfs_delete(dm, de_dotdot, DEVFS_DEL_NORECURSE);
363 if (DEVFS_DE_DROP(dd)) {
364 devfs_dirent_free(dd);
365 return;
366 }
367
368 de = dd;
369 }
370 }
371
372 /*
373 * The caller needs to hold the dm for the duration of the call since
374 * dm->dm_lock may be temporary dropped.
375 */
376 void
377 devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int flags)
378 {
379 struct devfs_dirent *dd;
380 struct vnode *vp;
381
382 KASSERT((de->de_flags & DE_DOOMED) == 0,
383 ("devfs_delete doomed dirent"));
384 de->de_flags |= DE_DOOMED;
385
386 if ((flags & DEVFS_DEL_NORECURSE) == 0) {
387 dd = devfs_parent_dirent(de);
388 if (dd != NULL)
389 DEVFS_DE_HOLD(dd);
390 if (de->de_flags & DE_USER) {
391 KASSERT(dd != NULL, ("devfs_delete: NULL dd"));
392 devfs_dir_unref_de(dm, dd);
393 }
394 } else
395 dd = NULL;
396
397 mtx_lock(&devfs_de_interlock);
398 vp = de->de_vnode;
399 if (vp != NULL) {
400 VI_LOCK(vp);
401 mtx_unlock(&devfs_de_interlock);
402 vholdl(vp);
403 sx_unlock(&dm->dm_lock);
404 if ((flags & DEVFS_DEL_VNLOCKED) == 0)
405 vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY);
406 else
407 VI_UNLOCK(vp);
408 vgone(vp);
409 if ((flags & DEVFS_DEL_VNLOCKED) == 0)
410 VOP_UNLOCK(vp);
411 vdrop(vp);
412 sx_xlock(&dm->dm_lock);
413 } else
414 mtx_unlock(&devfs_de_interlock);
415 if (de->de_symlink) {
416 free(de->de_symlink, M_DEVFS);
417 de->de_symlink = NULL;
418 }
419 #ifdef MAC
420 mac_devfs_destroy(de);
421 #endif
422 if (de->de_inode > DEVFS_ROOTINO) {
423 devfs_free_cdp_inode(de->de_inode);
424 de->de_inode = 0;
425 }
426 if (DEVFS_DE_DROP(de))
427 devfs_dirent_free(de);
428
429 if (dd != NULL) {
430 if (DEVFS_DE_DROP(dd))
431 devfs_dirent_free(dd);
432 else
433 devfs_rmdir_empty(dm, dd);
434 }
435 }
436
437 /*
438 * Called on unmount.
439 * Recursively removes the entire tree.
440 * The caller needs to hold the dm for the duration of the call.
441 */
442
443 static void
444 devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd)
445 {
446 struct devfs_dirent *de;
447
448 sx_assert(&dm->dm_lock, SX_XLOCKED);
449
450 DEVFS_DE_HOLD(dd);
451 for (;;) {
452 /*
453 * Use TAILQ_LAST() to remove "." and ".." last.
454 * We might need ".." to resolve a path in
455 * devfs_dir_unref_de().
456 */
457 de = TAILQ_LAST(&dd->de_dlist, devfs_dlist_head);
458 if (de == NULL)
459 break;
460 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
461 if (de->de_flags & DE_USER)
462 devfs_dir_unref_de(dm, dd);
463 if (de->de_flags & (DE_DOT | DE_DOTDOT))
464 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
465 else if (de->de_dirent->d_type == DT_DIR)
466 devfs_purge(dm, de);
467 else
468 devfs_delete(dm, de, DEVFS_DEL_NORECURSE);
469 }
470 if (DEVFS_DE_DROP(dd))
471 devfs_dirent_free(dd);
472 else if ((dd->de_flags & DE_DOOMED) == 0)
473 devfs_delete(dm, dd, DEVFS_DEL_NORECURSE);
474 }
475
476 /*
477 * Each cdev_priv has an array of pointers to devfs_dirent which is indexed
478 * by the mount points dm_idx.
479 * This function extends the array when necessary, taking into account that
480 * the default array is 1 element and not malloc'ed.
481 */
482 static void
483 devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm)
484 {
485 struct devfs_dirent **dep, **olddep;
486 int siz;
487
488 siz = (dm->dm_idx + 1) * sizeof *dep;
489 dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO);
490 dev_lock();
491 if (dm->dm_idx <= cdp->cdp_maxdirent) {
492 /* We got raced */
493 dev_unlock();
494 free(dep, M_DEVFS2);
495 return;
496 }
497 memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep);
498 olddep = cdp->cdp_maxdirent > 0 ? cdp->cdp_dirents : NULL;
499 cdp->cdp_dirents = dep;
500 /*
501 * XXX: if malloc told us how much we actually got this could
502 * XXX: be optimized.
503 */
504 cdp->cdp_maxdirent = dm->dm_idx;
505 dev_unlock();
506 free(olddep, M_DEVFS2);
507 }
508
509 /*
510 * The caller needs to hold the dm for the duration of the call.
511 */
512 static int
513 devfs_populate_loop(struct devfs_mount *dm, int cleanup)
514 {
515 struct cdev_priv *cdp;
516 struct devfs_dirent *de;
517 struct devfs_dirent *dd, *dt;
518 struct cdev *pdev;
519 int de_flags, depth, j;
520 char *q, *s;
521
522 sx_assert(&dm->dm_lock, SX_XLOCKED);
523 dev_lock();
524 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
525 KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents"));
526
527 /*
528 * If we are unmounting, or the device has been destroyed,
529 * clean up our dirent.
530 */
531 if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) &&
532 dm->dm_idx <= cdp->cdp_maxdirent &&
533 cdp->cdp_dirents[dm->dm_idx] != NULL) {
534 de = cdp->cdp_dirents[dm->dm_idx];
535 cdp->cdp_dirents[dm->dm_idx] = NULL;
536 KASSERT(cdp == de->de_cdp,
537 ("%s %d %s %p %p", __func__, __LINE__,
538 cdp->cdp_c.si_name, cdp, de->de_cdp));
539 KASSERT(de->de_dir != NULL, ("Null de->de_dir"));
540 dev_unlock();
541
542 TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list);
543 de->de_cdp = NULL;
544 de->de_inode = 0;
545 devfs_delete(dm, de, 0);
546 dev_lock();
547 cdp->cdp_inuse--;
548 dev_unlock();
549 return (1);
550 }
551 /*
552 * GC any lingering devices
553 */
554 if (!(cdp->cdp_flags & CDP_ACTIVE)) {
555 if (cdp->cdp_inuse > 0)
556 continue;
557 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
558 dev_unlock();
559 dev_rel(&cdp->cdp_c);
560 return (1);
561 }
562 /*
563 * Don't create any new dirents if we are unmounting
564 */
565 if (cleanup)
566 continue;
567 KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!"));
568
569 if (dm->dm_idx <= cdp->cdp_maxdirent &&
570 cdp->cdp_dirents[dm->dm_idx] != NULL) {
571 de = cdp->cdp_dirents[dm->dm_idx];
572 KASSERT(cdp == de->de_cdp, ("inconsistent cdp"));
573 continue;
574 }
575
576 cdp->cdp_inuse++;
577 dev_unlock();
578
579 if (dm->dm_idx > cdp->cdp_maxdirent)
580 devfs_metoo(cdp, dm);
581
582 dd = dm->dm_rootdir;
583 s = cdp->cdp_c.si_name;
584 for (;;) {
585 for (q = s; *q != '/' && *q != '\0'; q++)
586 continue;
587 if (*q != '/')
588 break;
589 de = devfs_find(dd, s, q - s, 0);
590 if (de == NULL)
591 de = devfs_vmkdir(dm, s, q - s, dd, 0);
592 else if (de->de_dirent->d_type == DT_LNK) {
593 de = devfs_find(dd, s, q - s, DT_DIR);
594 if (de == NULL)
595 de = devfs_vmkdir(dm, s, q - s, dd, 0);
596 de->de_flags |= DE_COVERED;
597 }
598 s = q + 1;
599 dd = de;
600 KASSERT(dd->de_dirent->d_type == DT_DIR &&
601 (dd->de_flags & (DE_DOT | DE_DOTDOT)) == 0,
602 ("%s: invalid directory (si_name=%s)",
603 __func__, cdp->cdp_c.si_name));
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 int
659 devfs_populate_needed(struct devfs_mount *dm)
660 {
661
662 return (dm->dm_generation != devfs_generation);
663 }
664
665 /*
666 * The caller needs to hold the dm for the duration of the call.
667 */
668 void
669 devfs_populate(struct devfs_mount *dm)
670 {
671 unsigned gen;
672
673 sx_assert(&dm->dm_lock, SX_XLOCKED);
674 if (!devfs_populate_needed(dm))
675 return;
676 gen = devfs_generation;
677 while (devfs_populate_loop(dm, 0))
678 continue;
679 dm->dm_generation = gen;
680 }
681
682 /*
683 * The caller needs to hold the dm for the duration of the call.
684 */
685 void
686 devfs_cleanup(struct devfs_mount *dm)
687 {
688
689 sx_assert(&dm->dm_lock, SX_XLOCKED);
690 while (devfs_populate_loop(dm, 1))
691 continue;
692 devfs_purge(dm, dm->dm_rootdir);
693 }
694
695 /*
696 * devfs_create() and devfs_destroy() are called from kern_conf.c and
697 * in both cases the devlock() mutex is held, so no further locking
698 * is necessary and no sleeping allowed.
699 */
700
701 void
702 devfs_create(struct cdev *dev)
703 {
704 struct cdev_priv *cdp;
705
706 dev_lock_assert_locked();
707 cdp = cdev2priv(dev);
708 cdp->cdp_flags |= CDP_ACTIVE;
709 cdp->cdp_inode = alloc_unrl(devfs_inos);
710 dev_refl(dev);
711 TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list);
712 devfs_generation++;
713 }
714
715 void
716 devfs_destroy(struct cdev *dev)
717 {
718 struct cdev_priv *cdp;
719
720 dev_lock_assert_locked();
721 cdp = cdev2priv(dev);
722 cdp->cdp_flags &= ~CDP_ACTIVE;
723 devfs_generation++;
724 }
725
726 ino_t
727 devfs_alloc_cdp_inode(void)
728 {
729
730 return (alloc_unr(devfs_inos));
731 }
732
733 void
734 devfs_free_cdp_inode(ino_t ino)
735 {
736
737 if (ino > 0)
738 free_unr(devfs_inos, ino);
739 }
740
741 static void
742 devfs_devs_init(void *junk __unused)
743 {
744
745 devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx);
746 }
747
748 SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL);
Cache object: 00da705074629a472aca978c93dcf121
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