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