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: head/sys/fs/devfs/devfs_devs.c 187864 2009-01-28 19:58:05Z ed $
29 */
30
31#include "opt_mac.h"
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 */
57struct cdev_priv_list cdevp_list = TAILQ_HEAD_INITIALIZER(cdevp_list);
58
59struct unrhdr *devfs_inos;
60
61
62static MALLOC_DEFINE(M_DEVFS2, "DEVFS2", "DEVFS data 2");
63static MALLOC_DEFINE(M_DEVFS3, "DEVFS3", "DEVFS data 3");
64static MALLOC_DEFINE(M_CDEVP, "DEVFS1", "DEVFS cdev_priv storage");
65
66static SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "DEVFS filesystem");
67
68static unsigned devfs_generation;
69SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD,
70 &devfs_generation, 0, "DEVFS generation number");
71
72unsigned devfs_rule_depth = 1;
73SYSCTL_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 struct cdev * and return
78 * the name, if any, registered by the device driver.
79 */
80static int
81sysctl_devname(SYSCTL_HANDLER_ARGS)
82{
83 int error;
84 dev_t ud;
85 struct cdev_priv *cdp;
86
87 error = SYSCTL_IN(req, &ud, sizeof (ud));
88 if (error)
89 return (error);
90 if (ud == NODEV)
91 return(EINVAL);
92/*
93 ud ^ devfs_random();
94*/
95 dev_lock();
96 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list)
97 if (cdp->cdp_inode == ud)
98 break;
99 dev_unlock();
100 if (cdp == NULL)
101 return(ENOENT);
102 return(SYSCTL_OUT(req, cdp->cdp_c.si_name, strlen(cdp->cdp_c.si_name) + 1));
103 return (error);
104}
105
106SYSCTL_PROC(_kern, OID_AUTO, devname,
107 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE,
108 NULL, 0, sysctl_devname, "", "devname(3) handler");
109
110SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
111 0, sizeof(struct cdev), "sizeof(struct cdev)");
112
113SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev_priv, CTLFLAG_RD,
114 0, sizeof(struct cdev_priv), "sizeof(struct cdev_priv)");
115
116struct cdev *
117devfs_alloc(void)
118{
119 struct cdev_priv *cdp;
120 struct cdev *cdev;
121 struct timespec ts;
122
123 cdp = malloc(sizeof *cdp, M_CDEVP, M_USE_RESERVE | M_ZERO | M_WAITOK);
124
125 cdp->cdp_dirents = &cdp->cdp_dirent0;
126 cdp->cdp_dirent0 = NULL;
127 cdp->cdp_maxdirent = 0;
128
129 cdev = &cdp->cdp_c;
130
131 cdev->si_name = cdev->__si_namebuf;
132 LIST_INIT(&cdev->si_children);
133 vfs_timestamp(&ts);
134 cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts;
135
136 return (cdev);
137}
138
139void
140devfs_free(struct cdev *cdev)
141{
142 struct cdev_priv *cdp;
143
144 cdp = cdev2priv(cdev);
145 if (cdev->si_cred != NULL)
146 crfree(cdev->si_cred);
147 if (cdp->cdp_inode > 0)
148 free_unr(devfs_inos, cdp->cdp_inode);
149 if (cdp->cdp_maxdirent > 0)
150 free(cdp->cdp_dirents, M_DEVFS2);
151 free(cdp, M_CDEVP);
152}
153
154struct devfs_dirent *
155devfs_find(struct devfs_dirent *dd, const char *name, int namelen)
156{
157 struct devfs_dirent *de;
158
159 TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
160 if (namelen != de->de_dirent->d_namlen)
161 continue;
162 if (bcmp(name, de->de_dirent->d_name, namelen) != 0)
163 continue;
164 break;
165 }
166 return (de);
167}
168
169struct devfs_dirent *
170devfs_newdirent(char *name, int namelen)
171{
172 int i;
173 struct devfs_dirent *de;
174 struct dirent d;
175
176 d.d_namlen = namelen;
177 i = sizeof (*de) + GENERIC_DIRSIZ(&d);
178 de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO);
179 de->de_dirent = (struct dirent *)(de + 1);
180 de->de_dirent->d_namlen = namelen;
181 de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
182 bcopy(name, de->de_dirent->d_name, namelen);
183 de->de_dirent->d_name[namelen] = '\0';
184 vfs_timestamp(&de->de_ctime);
185 de->de_mtime = de->de_atime = de->de_ctime;
186 de->de_links = 1;
187 de->de_holdcnt = 1;
188#ifdef MAC
189 mac_devfs_init(de);
190#endif
191 return (de);
192}
193
194struct devfs_dirent *
195devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen, struct devfs_dirent *dotdot, u_int inode)
196{
197 struct devfs_dirent *dd;
198 struct devfs_dirent *de;
199
200 /* Create the new directory */
201 dd = devfs_newdirent(name, namelen);
202 TAILQ_INIT(&dd->de_dlist);
203 dd->de_dirent->d_type = DT_DIR;
204 dd->de_mode = 0555;
205 dd->de_links = 2;
206 dd->de_dir = dd;
207 if (inode != 0)
208 dd->de_inode = inode;
209 else
210 dd->de_inode = alloc_unr(devfs_inos);
211
212 /* Create the "." entry in the new directory */
213 de = devfs_newdirent(".", 1);
214 de->de_dirent->d_type = DT_DIR;
215 de->de_flags |= DE_DOT;
216 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
217 de->de_dir = dd;
218
219 /* Create the ".." entry in the new directory */
220 de = devfs_newdirent("..", 2);
221 de->de_dirent->d_type = DT_DIR;
222 de->de_flags |= DE_DOTDOT;
223 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
224 if (dotdot == NULL) {
225 de->de_dir = dd;
226 } else {
227 de->de_dir = dotdot;
228 TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list);
229 dotdot->de_links++;
230 }
231
232#ifdef MAC
233 mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd);
234#endif
235 return (dd);
236}
237
238void
239devfs_dirent_free(struct devfs_dirent *de)
240{
241 free(de, M_DEVFS3);
242}
243
244/*
245 * The caller needs to hold the dm for the duration of the call since
246 * dm->dm_lock may be temporary dropped.
247 */
248void
249devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int vp_locked)
250{
251 struct vnode *vp;
252
253 KASSERT((de->de_flags & DE_DOOMED) == 0,
254 ("devfs_delete doomed dirent"));
255 de->de_flags |= DE_DOOMED;
256 mtx_lock(&devfs_de_interlock);
257 vp = de->de_vnode;
258 if (vp != NULL) {
259 VI_LOCK(vp);
260 mtx_unlock(&devfs_de_interlock);
261 vholdl(vp);
262 sx_unlock(&dm->dm_lock);
263 if (!vp_locked)
264 vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY);
265 else
266 VI_UNLOCK(vp);
267 vgone(vp);
268 if (!vp_locked)
269 VOP_UNLOCK(vp, 0);
270 vdrop(vp);
271 sx_xlock(&dm->dm_lock);
272 } else
273 mtx_unlock(&devfs_de_interlock);
274 if (de->de_symlink) {
275 free(de->de_symlink, M_DEVFS);
276 de->de_symlink = NULL;
277 }
278#ifdef MAC
279 mac_devfs_destroy(de);
280#endif
281 if (de->de_inode > DEVFS_ROOTINO) {
282 free_unr(devfs_inos, de->de_inode);
283 de->de_inode = 0;
284 }
285 if (DEVFS_DE_DROP(de))
286 devfs_dirent_free(de);
287}
288
289/*
290 * Called on unmount.
291 * Recursively removes the entire tree.
292 * The caller needs to hold the dm for the duration of the call.
293 */
294
295static void
296devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd)
297{
298 struct devfs_dirent *de;
299
300 sx_assert(&dm->dm_lock, SX_XLOCKED);
301 for (;;) {
302 de = TAILQ_FIRST(&dd->de_dlist);
303 if (de == NULL)
304 break;
305 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
306 if (de->de_flags & (DE_DOT|DE_DOTDOT))
307 devfs_delete(dm, de, 0);
308 else if (de->de_dirent->d_type == DT_DIR)
309 devfs_purge(dm, de);
310 else
311 devfs_delete(dm, de, 0);
312 }
313 devfs_delete(dm, dd, 0);
314}
315
316/*
317 * Each cdev_priv has an array of pointers to devfs_dirent which is indexed
318 * by the mount points dm_idx.
319 * This function extends the array when necessary, taking into account that
320 * the default array is 1 element and not malloc'ed.
321 */
322static void
323devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm)
324{
325 struct devfs_dirent **dep;
326 int siz;
327
328 siz = (dm->dm_idx + 1) * sizeof *dep;
329 dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO);
330 dev_lock();
331 if (dm->dm_idx <= cdp->cdp_maxdirent) {
332 /* We got raced */
333 dev_unlock();
334 free(dep, M_DEVFS2);
335 return;
336 }
337 memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep);
338 if (cdp->cdp_maxdirent > 0)
339 free(cdp->cdp_dirents, M_DEVFS2);
340 cdp->cdp_dirents = dep;
341 /*
342 * XXX: if malloc told us how much we actually got this could
343 * XXX: be optimized.
344 */
345 cdp->cdp_maxdirent = dm->dm_idx;
346 dev_unlock();
347}
348
349/*
350 * The caller needs to hold the dm for the duration of the call.
351 */
352static int
353devfs_populate_loop(struct devfs_mount *dm, int cleanup)
354{
355 struct cdev_priv *cdp;
356 struct devfs_dirent *de;
357 struct devfs_dirent *dd;
358 struct cdev *pdev;
359 int j;
360 char *q, *s;
361
362 sx_assert(&dm->dm_lock, SX_XLOCKED);
363 dev_lock();
364 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
365
366 KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents"));
367
368 /*
369 * If we are unmounting, or the device has been destroyed,
370 * clean up our dirent.
371 */
372 if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) &&
373 dm->dm_idx <= cdp->cdp_maxdirent &&
374 cdp->cdp_dirents[dm->dm_idx] != NULL) {
375 de = cdp->cdp_dirents[dm->dm_idx];
376 cdp->cdp_dirents[dm->dm_idx] = NULL;
377 KASSERT(cdp == de->de_cdp,
378 ("%s %d %s %p %p", __func__, __LINE__,
379 cdp->cdp_c.si_name, cdp, de->de_cdp));
380 KASSERT(de->de_dir != NULL, ("Null de->de_dir"));
381 dev_unlock();
382
383 TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list);
384 de->de_cdp = NULL;
385 de->de_inode = 0;
386 devfs_delete(dm, de, 0);
387 dev_lock();
388 cdp->cdp_inuse--;
389 dev_unlock();
390 return (1);
391 }
392 /*
393 * GC any lingering devices
394 */
395 if (!(cdp->cdp_flags & CDP_ACTIVE)) {
396 if (cdp->cdp_inuse > 0)
397 continue;
398 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
399 dev_unlock();
400 dev_rel(&cdp->cdp_c);
401 return (1);
402 }
403 /*
404 * Don't create any new dirents if we are unmounting
405 */
406 if (cleanup)
407 continue;
408 KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!"));
409
410 if (dm->dm_idx <= cdp->cdp_maxdirent &&
411 cdp->cdp_dirents[dm->dm_idx] != NULL) {
412 de = cdp->cdp_dirents[dm->dm_idx];
413 KASSERT(cdp == de->de_cdp, ("inconsistent cdp"));
414 continue;
415 }
416
417
418 cdp->cdp_inuse++;
419 dev_unlock();
420
421 if (dm->dm_idx > cdp->cdp_maxdirent)
422 devfs_metoo(cdp, dm);
423
424 dd = dm->dm_rootdir;
425 s = cdp->cdp_c.si_name;
426 for (;;) {
427 for (q = s; *q != '/' && *q != '\0'; q++)
428 continue;
429 if (*q != '/')
430 break;
431 de = devfs_find(dd, s, q - s);
432 if (de == NULL)
433 de = devfs_vmkdir(dm, s, q - s, dd, 0);
434 s = q + 1;
435 dd = de;
436 }
437
438 de = devfs_newdirent(s, q - s);
439 if (cdp->cdp_c.si_flags & SI_ALIAS) {
440 de->de_uid = 0;
441 de->de_gid = 0;
442 de->de_mode = 0755;
443 de->de_dirent->d_type = DT_LNK;
444 pdev = cdp->cdp_c.si_parent;
445 j = strlen(pdev->si_name) + 1;
446 de->de_symlink = malloc(j, M_DEVFS, M_WAITOK);
447 bcopy(pdev->si_name, de->de_symlink, j);
448 } else {
449 de->de_uid = cdp->cdp_c.si_uid;
450 de->de_gid = cdp->cdp_c.si_gid;
451 de->de_mode = cdp->cdp_c.si_mode;
452 de->de_dirent->d_type = DT_CHR;
453 }
454 de->de_inode = cdp->cdp_inode;
455 de->de_cdp = cdp;
456#ifdef MAC
457 mac_devfs_create_device(cdp->cdp_c.si_cred, dm->dm_mount,
458 &cdp->cdp_c, de);
459#endif
460 de->de_dir = dd;
461 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
462 devfs_rules_apply(dm, de);
463 dev_lock();
464 /* XXX: could check that cdp is still active here */
465 KASSERT(cdp->cdp_dirents[dm->dm_idx] == NULL,
466 ("%s %d\n", __func__, __LINE__));
467 cdp->cdp_dirents[dm->dm_idx] = de;
468 KASSERT(de->de_cdp != (void *)0xdeadc0de,
469 ("%s %d\n", __func__, __LINE__));
470 dev_unlock();
471 return (1);
472 }
473 dev_unlock();
474 return (0);
475}
476
477/*
478 * The caller needs to hold the dm for the duration of the call.
479 */
480void
481devfs_populate(struct devfs_mount *dm)
482{
483
484 sx_assert(&dm->dm_lock, SX_XLOCKED);
485 if (dm->dm_generation == devfs_generation)
486 return;
487 while (devfs_populate_loop(dm, 0))
488 continue;
489 dm->dm_generation = devfs_generation;
490}
491
492/*
493 * The caller needs to hold the dm for the duration of the call.
494 */
495void
496devfs_cleanup(struct devfs_mount *dm)
497{
498
499 sx_assert(&dm->dm_lock, SX_XLOCKED);
500 while (devfs_populate_loop(dm, 1))
501 continue;
502 devfs_purge(dm, dm->dm_rootdir);
503}
504
505/*
506 * devfs_create() and devfs_destroy() are called from kern_conf.c and
507 * in both cases the devlock() mutex is held, so no further locking
508 * is necesary and no sleeping allowed.
509 */
510
511void
512devfs_create(struct cdev *dev)
513{
514 struct cdev_priv *cdp;
515
516 mtx_assert(&devmtx, MA_OWNED);
517 cdp = cdev2priv(dev);
518 cdp->cdp_flags |= CDP_ACTIVE;
519 cdp->cdp_inode = alloc_unrl(devfs_inos);
520 dev_refl(dev);
521 TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list);
522 devfs_generation++;
523}
524
525void
526devfs_destroy(struct cdev *dev)
527{
528 struct cdev_priv *cdp;
529
530 mtx_assert(&devmtx, MA_OWNED);
531 cdp = cdev2priv(dev);
532 cdp->cdp_flags &= ~CDP_ACTIVE;
533 devfs_generation++;
534}
535
536static void
537devfs_devs_init(void *junk __unused)
538{
539
540 devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx);
541}
542
543SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL);
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: head/sys/fs/devfs/devfs_devs.c 187864 2009-01-28 19:58:05Z ed $
29 */
30
31#include "opt_mac.h"
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 */
57struct cdev_priv_list cdevp_list = TAILQ_HEAD_INITIALIZER(cdevp_list);
58
59struct unrhdr *devfs_inos;
60
61
62static MALLOC_DEFINE(M_DEVFS2, "DEVFS2", "DEVFS data 2");
63static MALLOC_DEFINE(M_DEVFS3, "DEVFS3", "DEVFS data 3");
64static MALLOC_DEFINE(M_CDEVP, "DEVFS1", "DEVFS cdev_priv storage");
65
66static SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "DEVFS filesystem");
67
68static unsigned devfs_generation;
69SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD,
70 &devfs_generation, 0, "DEVFS generation number");
71
72unsigned devfs_rule_depth = 1;
73SYSCTL_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 struct cdev * and return
78 * the name, if any, registered by the device driver.
79 */
80static int
81sysctl_devname(SYSCTL_HANDLER_ARGS)
82{
83 int error;
84 dev_t ud;
85 struct cdev_priv *cdp;
86
87 error = SYSCTL_IN(req, &ud, sizeof (ud));
88 if (error)
89 return (error);
90 if (ud == NODEV)
91 return(EINVAL);
92/*
93 ud ^ devfs_random();
94*/
95 dev_lock();
96 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list)
97 if (cdp->cdp_inode == ud)
98 break;
99 dev_unlock();
100 if (cdp == NULL)
101 return(ENOENT);
102 return(SYSCTL_OUT(req, cdp->cdp_c.si_name, strlen(cdp->cdp_c.si_name) + 1));
103 return (error);
104}
105
106SYSCTL_PROC(_kern, OID_AUTO, devname,
107 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE,
108 NULL, 0, sysctl_devname, "", "devname(3) handler");
109
110SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
111 0, sizeof(struct cdev), "sizeof(struct cdev)");
112
113SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev_priv, CTLFLAG_RD,
114 0, sizeof(struct cdev_priv), "sizeof(struct cdev_priv)");
115
116struct cdev *
117devfs_alloc(void)
118{
119 struct cdev_priv *cdp;
120 struct cdev *cdev;
121 struct timespec ts;
122
123 cdp = malloc(sizeof *cdp, M_CDEVP, M_USE_RESERVE | M_ZERO | M_WAITOK);
124
125 cdp->cdp_dirents = &cdp->cdp_dirent0;
126 cdp->cdp_dirent0 = NULL;
127 cdp->cdp_maxdirent = 0;
128
129 cdev = &cdp->cdp_c;
130
131 cdev->si_name = cdev->__si_namebuf;
132 LIST_INIT(&cdev->si_children);
133 vfs_timestamp(&ts);
134 cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts;
135
136 return (cdev);
137}
138
139void
140devfs_free(struct cdev *cdev)
141{
142 struct cdev_priv *cdp;
143
144 cdp = cdev2priv(cdev);
145 if (cdev->si_cred != NULL)
146 crfree(cdev->si_cred);
147 if (cdp->cdp_inode > 0)
148 free_unr(devfs_inos, cdp->cdp_inode);
149 if (cdp->cdp_maxdirent > 0)
150 free(cdp->cdp_dirents, M_DEVFS2);
151 free(cdp, M_CDEVP);
152}
153
154struct devfs_dirent *
155devfs_find(struct devfs_dirent *dd, const char *name, int namelen)
156{
157 struct devfs_dirent *de;
158
159 TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
160 if (namelen != de->de_dirent->d_namlen)
161 continue;
162 if (bcmp(name, de->de_dirent->d_name, namelen) != 0)
163 continue;
164 break;
165 }
166 return (de);
167}
168
169struct devfs_dirent *
170devfs_newdirent(char *name, int namelen)
171{
172 int i;
173 struct devfs_dirent *de;
174 struct dirent d;
175
176 d.d_namlen = namelen;
177 i = sizeof (*de) + GENERIC_DIRSIZ(&d);
178 de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO);
179 de->de_dirent = (struct dirent *)(de + 1);
180 de->de_dirent->d_namlen = namelen;
181 de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
182 bcopy(name, de->de_dirent->d_name, namelen);
183 de->de_dirent->d_name[namelen] = '\0';
184 vfs_timestamp(&de->de_ctime);
185 de->de_mtime = de->de_atime = de->de_ctime;
186 de->de_links = 1;
187 de->de_holdcnt = 1;
188#ifdef MAC
189 mac_devfs_init(de);
190#endif
191 return (de);
192}
193
194struct devfs_dirent *
195devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen, struct devfs_dirent *dotdot, u_int inode)
196{
197 struct devfs_dirent *dd;
198 struct devfs_dirent *de;
199
200 /* Create the new directory */
201 dd = devfs_newdirent(name, namelen);
202 TAILQ_INIT(&dd->de_dlist);
203 dd->de_dirent->d_type = DT_DIR;
204 dd->de_mode = 0555;
205 dd->de_links = 2;
206 dd->de_dir = dd;
207 if (inode != 0)
208 dd->de_inode = inode;
209 else
210 dd->de_inode = alloc_unr(devfs_inos);
211
212 /* Create the "." entry in the new directory */
213 de = devfs_newdirent(".", 1);
214 de->de_dirent->d_type = DT_DIR;
215 de->de_flags |= DE_DOT;
216 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
217 de->de_dir = dd;
218
219 /* Create the ".." entry in the new directory */
220 de = devfs_newdirent("..", 2);
221 de->de_dirent->d_type = DT_DIR;
222 de->de_flags |= DE_DOTDOT;
223 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
224 if (dotdot == NULL) {
225 de->de_dir = dd;
226 } else {
227 de->de_dir = dotdot;
228 TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list);
229 dotdot->de_links++;
230 }
231
232#ifdef MAC
233 mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd);
234#endif
235 return (dd);
236}
237
238void
239devfs_dirent_free(struct devfs_dirent *de)
240{
241 free(de, M_DEVFS3);
242}
243
244/*
245 * The caller needs to hold the dm for the duration of the call since
246 * dm->dm_lock may be temporary dropped.
247 */
248void
249devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int vp_locked)
250{
251 struct vnode *vp;
252
253 KASSERT((de->de_flags & DE_DOOMED) == 0,
254 ("devfs_delete doomed dirent"));
255 de->de_flags |= DE_DOOMED;
256 mtx_lock(&devfs_de_interlock);
257 vp = de->de_vnode;
258 if (vp != NULL) {
259 VI_LOCK(vp);
260 mtx_unlock(&devfs_de_interlock);
261 vholdl(vp);
262 sx_unlock(&dm->dm_lock);
263 if (!vp_locked)
264 vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY);
265 else
266 VI_UNLOCK(vp);
267 vgone(vp);
268 if (!vp_locked)
269 VOP_UNLOCK(vp, 0);
270 vdrop(vp);
271 sx_xlock(&dm->dm_lock);
272 } else
273 mtx_unlock(&devfs_de_interlock);
274 if (de->de_symlink) {
275 free(de->de_symlink, M_DEVFS);
276 de->de_symlink = NULL;
277 }
278#ifdef MAC
279 mac_devfs_destroy(de);
280#endif
281 if (de->de_inode > DEVFS_ROOTINO) {
282 free_unr(devfs_inos, de->de_inode);
283 de->de_inode = 0;
284 }
285 if (DEVFS_DE_DROP(de))
286 devfs_dirent_free(de);
287}
288
289/*
290 * Called on unmount.
291 * Recursively removes the entire tree.
292 * The caller needs to hold the dm for the duration of the call.
293 */
294
295static void
296devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd)
297{
298 struct devfs_dirent *de;
299
300 sx_assert(&dm->dm_lock, SX_XLOCKED);
301 for (;;) {
302 de = TAILQ_FIRST(&dd->de_dlist);
303 if (de == NULL)
304 break;
305 TAILQ_REMOVE(&dd->de_dlist, de, de_list);
306 if (de->de_flags & (DE_DOT|DE_DOTDOT))
307 devfs_delete(dm, de, 0);
308 else if (de->de_dirent->d_type == DT_DIR)
309 devfs_purge(dm, de);
310 else
311 devfs_delete(dm, de, 0);
312 }
313 devfs_delete(dm, dd, 0);
314}
315
316/*
317 * Each cdev_priv has an array of pointers to devfs_dirent which is indexed
318 * by the mount points dm_idx.
319 * This function extends the array when necessary, taking into account that
320 * the default array is 1 element and not malloc'ed.
321 */
322static void
323devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm)
324{
325 struct devfs_dirent **dep;
326 int siz;
327
328 siz = (dm->dm_idx + 1) * sizeof *dep;
329 dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO);
330 dev_lock();
331 if (dm->dm_idx <= cdp->cdp_maxdirent) {
332 /* We got raced */
333 dev_unlock();
334 free(dep, M_DEVFS2);
335 return;
336 }
337 memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep);
338 if (cdp->cdp_maxdirent > 0)
339 free(cdp->cdp_dirents, M_DEVFS2);
340 cdp->cdp_dirents = dep;
341 /*
342 * XXX: if malloc told us how much we actually got this could
343 * XXX: be optimized.
344 */
345 cdp->cdp_maxdirent = dm->dm_idx;
346 dev_unlock();
347}
348
349/*
350 * The caller needs to hold the dm for the duration of the call.
351 */
352static int
353devfs_populate_loop(struct devfs_mount *dm, int cleanup)
354{
355 struct cdev_priv *cdp;
356 struct devfs_dirent *de;
357 struct devfs_dirent *dd;
358 struct cdev *pdev;
359 int j;
360 char *q, *s;
361
362 sx_assert(&dm->dm_lock, SX_XLOCKED);
363 dev_lock();
364 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) {
365
366 KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents"));
367
368 /*
369 * If we are unmounting, or the device has been destroyed,
370 * clean up our dirent.
371 */
372 if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) &&
373 dm->dm_idx <= cdp->cdp_maxdirent &&
374 cdp->cdp_dirents[dm->dm_idx] != NULL) {
375 de = cdp->cdp_dirents[dm->dm_idx];
376 cdp->cdp_dirents[dm->dm_idx] = NULL;
377 KASSERT(cdp == de->de_cdp,
378 ("%s %d %s %p %p", __func__, __LINE__,
379 cdp->cdp_c.si_name, cdp, de->de_cdp));
380 KASSERT(de->de_dir != NULL, ("Null de->de_dir"));
381 dev_unlock();
382
383 TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list);
384 de->de_cdp = NULL;
385 de->de_inode = 0;
386 devfs_delete(dm, de, 0);
387 dev_lock();
388 cdp->cdp_inuse--;
389 dev_unlock();
390 return (1);
391 }
392 /*
393 * GC any lingering devices
394 */
395 if (!(cdp->cdp_flags & CDP_ACTIVE)) {
396 if (cdp->cdp_inuse > 0)
397 continue;
398 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list);
399 dev_unlock();
400 dev_rel(&cdp->cdp_c);
401 return (1);
402 }
403 /*
404 * Don't create any new dirents if we are unmounting
405 */
406 if (cleanup)
407 continue;
408 KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!"));
409
410 if (dm->dm_idx <= cdp->cdp_maxdirent &&
411 cdp->cdp_dirents[dm->dm_idx] != NULL) {
412 de = cdp->cdp_dirents[dm->dm_idx];
413 KASSERT(cdp == de->de_cdp, ("inconsistent cdp"));
414 continue;
415 }
416
417
418 cdp->cdp_inuse++;
419 dev_unlock();
420
421 if (dm->dm_idx > cdp->cdp_maxdirent)
422 devfs_metoo(cdp, dm);
423
424 dd = dm->dm_rootdir;
425 s = cdp->cdp_c.si_name;
426 for (;;) {
427 for (q = s; *q != '/' && *q != '\0'; q++)
428 continue;
429 if (*q != '/')
430 break;
431 de = devfs_find(dd, s, q - s);
432 if (de == NULL)
433 de = devfs_vmkdir(dm, s, q - s, dd, 0);
434 s = q + 1;
435 dd = de;
436 }
437
438 de = devfs_newdirent(s, q - s);
439 if (cdp->cdp_c.si_flags & SI_ALIAS) {
440 de->de_uid = 0;
441 de->de_gid = 0;
442 de->de_mode = 0755;
443 de->de_dirent->d_type = DT_LNK;
444 pdev = cdp->cdp_c.si_parent;
445 j = strlen(pdev->si_name) + 1;
446 de->de_symlink = malloc(j, M_DEVFS, M_WAITOK);
447 bcopy(pdev->si_name, de->de_symlink, j);
448 } else {
449 de->de_uid = cdp->cdp_c.si_uid;
450 de->de_gid = cdp->cdp_c.si_gid;
451 de->de_mode = cdp->cdp_c.si_mode;
452 de->de_dirent->d_type = DT_CHR;
453 }
454 de->de_inode = cdp->cdp_inode;
455 de->de_cdp = cdp;
456#ifdef MAC
457 mac_devfs_create_device(cdp->cdp_c.si_cred, dm->dm_mount,
458 &cdp->cdp_c, de);
459#endif
460 de->de_dir = dd;
461 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
462 devfs_rules_apply(dm, de);
463 dev_lock();
464 /* XXX: could check that cdp is still active here */
465 KASSERT(cdp->cdp_dirents[dm->dm_idx] == NULL,
466 ("%s %d\n", __func__, __LINE__));
467 cdp->cdp_dirents[dm->dm_idx] = de;
468 KASSERT(de->de_cdp != (void *)0xdeadc0de,
469 ("%s %d\n", __func__, __LINE__));
470 dev_unlock();
471 return (1);
472 }
473 dev_unlock();
474 return (0);
475}
476
477/*
478 * The caller needs to hold the dm for the duration of the call.
479 */
480void
481devfs_populate(struct devfs_mount *dm)
482{
483
484 sx_assert(&dm->dm_lock, SX_XLOCKED);
485 if (dm->dm_generation == devfs_generation)
486 return;
487 while (devfs_populate_loop(dm, 0))
488 continue;
489 dm->dm_generation = devfs_generation;
490}
491
492/*
493 * The caller needs to hold the dm for the duration of the call.
494 */
495void
496devfs_cleanup(struct devfs_mount *dm)
497{
498
499 sx_assert(&dm->dm_lock, SX_XLOCKED);
500 while (devfs_populate_loop(dm, 1))
501 continue;
502 devfs_purge(dm, dm->dm_rootdir);
503}
504
505/*
506 * devfs_create() and devfs_destroy() are called from kern_conf.c and
507 * in both cases the devlock() mutex is held, so no further locking
508 * is necesary and no sleeping allowed.
509 */
510
511void
512devfs_create(struct cdev *dev)
513{
514 struct cdev_priv *cdp;
515
516 mtx_assert(&devmtx, MA_OWNED);
517 cdp = cdev2priv(dev);
518 cdp->cdp_flags |= CDP_ACTIVE;
519 cdp->cdp_inode = alloc_unrl(devfs_inos);
520 dev_refl(dev);
521 TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list);
522 devfs_generation++;
523}
524
525void
526devfs_destroy(struct cdev *dev)
527{
528 struct cdev_priv *cdp;
529
530 mtx_assert(&devmtx, MA_OWNED);
531 cdp = cdev2priv(dev);
532 cdp->cdp_flags &= ~CDP_ACTIVE;
533 devfs_generation++;
534}
535
536static void
537devfs_devs_init(void *junk __unused)
538{
539
540 devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx);
541}
542
543SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL);