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 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 | CTLFLAG_MPSAFE, 0, 67 "DEVFS filesystem"); 68 69 static unsigned devfs_generation; 70 SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD, 71 &devfs_generation, 0, "DEVFS generation number"); 72 73 unsigned devfs_rule_depth = 1; 74 SYSCTL_UINT(_vfs_devfs, OID_AUTO, rule_depth, CTLFLAG_RW, 75 &devfs_rule_depth, 0, "Max depth of ruleset include"); 76 77 /* 78 * Helper sysctl for devname(3). We're given a dev_t and return the 79 * name, if any, registered by the device driver. 80 */ 81 static int 82 sysctl_devname(SYSCTL_HANDLER_ARGS) 83 { 84 int error; 85 dev_t ud; 86 #ifdef COMPAT_FREEBSD11 87 uint32_t ud_compat; 88 #endif 89 struct cdev_priv *cdp; 90 struct cdev *dev; 91 92 #ifdef COMPAT_FREEBSD11 93 if (req->newlen == sizeof(ud_compat)) { 94 error = SYSCTL_IN(req, &ud_compat, sizeof(ud_compat)); 95 if (error == 0) 96 ud = ud_compat == (uint32_t)NODEV ? NODEV : ud_compat; 97 } else 98 #endif 99 error = SYSCTL_IN(req, &ud, sizeof (ud)); 100 if (error) 101 return (error); 102 if (ud == NODEV) 103 return (EINVAL); 104 dev = NULL; 105 dev_lock(); 106 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) 107 if (cdp->cdp_inode == ud) { 108 dev = &cdp->cdp_c; 109 dev_refl(dev); 110 break; 111 } 112 dev_unlock(); 113 if (dev == NULL) 114 return (ENOENT); 115 error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); 116 dev_rel(dev); 117 return (error); 118 } 119 120 SYSCTL_PROC(_kern, OID_AUTO, devname, 121 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE, 122 NULL, 0, sysctl_devname, "", "devname(3) handler"); 123 124 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD, 125 SYSCTL_NULL_INT_PTR, sizeof(struct cdev), "sizeof(struct cdev)"); 126 127 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev_priv, CTLFLAG_RD, 128 SYSCTL_NULL_INT_PTR, sizeof(struct cdev_priv), "sizeof(struct cdev_priv)"); 129 130 struct cdev * 131 devfs_alloc(int flags) 132 { 133 struct cdev_priv *cdp; 134 struct cdev *cdev; 135 struct timespec ts; 136 137 cdp = malloc(sizeof *cdp, M_CDEVP, M_ZERO | 138 ((flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK)); 139 if (cdp == NULL) 140 return (NULL); 141 142 mtx_init(&cdp->cdp_threadlock, "devthrd", NULL, MTX_DEF); 143 144 cdp->cdp_dirents = &cdp->cdp_dirent0; 145 146 cdev = &cdp->cdp_c; 147 LIST_INIT(&cdev->si_children); 148 vfs_timestamp(&ts); 149 cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts; 150 151 return (cdev); 152 } 153 154 int 155 devfs_dev_exists(const char *name) 156 { 157 struct cdev_priv *cdp; 158 159 mtx_assert(&devmtx, MA_OWNED); 160 161 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 162 if ((cdp->cdp_flags & CDP_ACTIVE) == 0) 163 continue; 164 if (devfs_pathpath(cdp->cdp_c.si_name, name) != 0) 165 return (1); 166 if (devfs_pathpath(name, cdp->cdp_c.si_name) != 0) 167 return (1); 168 } 169 if (devfs_dir_find(name) != 0) 170 return (1); 171 172 return (0); 173 } 174 175 void 176 devfs_free(struct cdev *cdev) 177 { 178 struct cdev_priv *cdp; 179 180 cdp = cdev2priv(cdev); 181 if (cdev->si_cred != NULL) 182 crfree(cdev->si_cred); 183 devfs_free_cdp_inode(cdp->cdp_inode); 184 if (cdp->cdp_maxdirent > 0) 185 free(cdp->cdp_dirents, M_DEVFS2); 186 mtx_destroy(&cdp->cdp_threadlock); 187 free(cdp, M_CDEVP); 188 } 189 190 struct devfs_dirent * 191 devfs_find(struct devfs_dirent *dd, const char *name, int namelen, int type) 192 { 193 struct devfs_dirent *de; 194 195 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 196 if (namelen != de->de_dirent->d_namlen) 197 continue; 198 if (type != 0 && type != de->de_dirent->d_type) 199 continue; 200 201 /* 202 * The race with finding non-active name is not 203 * completely closed by the check, but it is similar 204 * to the devfs_allocv() in making it unlikely enough. 205 */ 206 if (de->de_dirent->d_type == DT_CHR && 207 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0) 208 continue; 209 210 if (bcmp(name, de->de_dirent->d_name, namelen) != 0) 211 continue; 212 break; 213 } 214 KASSERT(de == NULL || (de->de_flags & DE_DOOMED) == 0, 215 ("devfs_find: returning a doomed entry")); 216 return (de); 217 } 218 219 struct devfs_dirent * 220 devfs_newdirent(char *name, int namelen) 221 { 222 int i; 223 struct devfs_dirent *de; 224 struct dirent d; 225 226 d.d_namlen = namelen; 227 i = sizeof(*de) + GENERIC_DIRSIZ(&d); 228 de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO); 229 de->de_dirent = (struct dirent *)(de + 1); 230 de->de_dirent->d_namlen = namelen; 231 de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d); 232 bcopy(name, de->de_dirent->d_name, namelen); 233 dirent_terminate(de->de_dirent); 234 vfs_timestamp(&de->de_ctime); 235 de->de_mtime = de->de_atime = de->de_ctime; 236 de->de_links = 1; 237 de->de_holdcnt = 1; 238 #ifdef MAC 239 mac_devfs_init(de); 240 #endif 241 return (de); 242 } 243 244 struct devfs_dirent * 245 devfs_parent_dirent(struct devfs_dirent *de) 246 { 247 248 if (de->de_dirent->d_type != DT_DIR) 249 return (de->de_dir); 250 251 if (de->de_flags & (DE_DOT | DE_DOTDOT)) 252 return (NULL); 253 254 de = TAILQ_FIRST(&de->de_dlist); /* "." */ 255 if (de == NULL) 256 return (NULL); 257 de = TAILQ_NEXT(de, de_list); /* ".." */ 258 if (de == NULL) 259 return (NULL); 260 261 return (de->de_dir); 262 } 263 264 struct devfs_dirent * 265 devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen, 266 struct devfs_dirent *dotdot, u_int inode) 267 { 268 struct devfs_dirent *dd; 269 struct devfs_dirent *de; 270 271 /* Create the new directory */ 272 dd = devfs_newdirent(name, namelen); 273 TAILQ_INIT(&dd->de_dlist); 274 dd->de_dirent->d_type = DT_DIR; 275 dd->de_mode = 0555; 276 dd->de_links = 2; 277 dd->de_dir = dd; 278 if (inode != 0) 279 dd->de_inode = inode; 280 else 281 dd->de_inode = alloc_unr(devfs_inos); 282 283 /* 284 * "." and ".." are always the two first entries in the 285 * de_dlist list. 286 * 287 * Create the "." entry in the new directory. 288 */ 289 de = devfs_newdirent(".", 1); 290 de->de_dirent->d_type = DT_DIR; 291 de->de_flags |= DE_DOT; 292 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); 293 de->de_dir = dd; 294 295 /* Create the ".." entry in the new directory. */ 296 de = devfs_newdirent("..", 2); 297 de->de_dirent->d_type = DT_DIR; 298 de->de_flags |= DE_DOTDOT; 299 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); 300 if (dotdot == NULL) { 301 de->de_dir = dd; 302 } else { 303 de->de_dir = dotdot; 304 sx_assert(&dmp->dm_lock, SX_XLOCKED); 305 TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list); 306 dotdot->de_links++; 307 devfs_rules_apply(dmp, dd); 308 } 309 310 #ifdef MAC 311 mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd); 312 #endif 313 return (dd); 314 } 315 316 void 317 devfs_dirent_free(struct devfs_dirent *de) 318 { 319 struct vnode *vp; 320 321 vp = de->de_vnode; 322 mtx_lock(&devfs_de_interlock); 323 if (vp != NULL && vp->v_data == de) 324 vp->v_data = NULL; 325 mtx_unlock(&devfs_de_interlock); 326 free(de, M_DEVFS3); 327 } 328 329 /* 330 * Removes a directory if it is empty. Also empty parent directories are 331 * removed recursively. 332 */ 333 static void 334 devfs_rmdir_empty(struct devfs_mount *dm, struct devfs_dirent *de) 335 { 336 struct devfs_dirent *dd, *de_dot, *de_dotdot; 337 338 sx_assert(&dm->dm_lock, SX_XLOCKED); 339 340 for (;;) { 341 KASSERT(de->de_dirent->d_type == DT_DIR, 342 ("devfs_rmdir_empty: de is not a directory")); 343 344 if ((de->de_flags & DE_DOOMED) != 0 || de == dm->dm_rootdir) 345 return; 346 347 de_dot = TAILQ_FIRST(&de->de_dlist); 348 KASSERT(de_dot != NULL, ("devfs_rmdir_empty: . missing")); 349 de_dotdot = TAILQ_NEXT(de_dot, de_list); 350 KASSERT(de_dotdot != NULL, ("devfs_rmdir_empty: .. missing")); 351 /* Return if the directory is not empty. */ 352 if (TAILQ_NEXT(de_dotdot, de_list) != NULL) 353 return; 354 355 dd = devfs_parent_dirent(de); 356 KASSERT(dd != NULL, ("devfs_rmdir_empty: NULL dd")); 357 TAILQ_REMOVE(&de->de_dlist, de_dot, de_list); 358 TAILQ_REMOVE(&de->de_dlist, de_dotdot, de_list); 359 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 360 DEVFS_DE_HOLD(dd); 361 devfs_delete(dm, de, DEVFS_DEL_NORECURSE); 362 devfs_delete(dm, de_dot, DEVFS_DEL_NORECURSE); 363 devfs_delete(dm, de_dotdot, DEVFS_DEL_NORECURSE); 364 if (DEVFS_DE_DROP(dd)) { 365 devfs_dirent_free(dd); 366 return; 367 } 368 369 de = dd; 370 } 371 } 372 373 /* 374 * The caller needs to hold the dm for the duration of the call since 375 * dm->dm_lock may be temporary dropped. 376 */ 377 void 378 devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int flags) 379 { 380 struct devfs_dirent *dd; 381 struct vnode *vp; 382 383 KASSERT((de->de_flags & DE_DOOMED) == 0, 384 ("devfs_delete doomed dirent")); 385 de->de_flags |= DE_DOOMED; 386 387 if ((flags & DEVFS_DEL_NORECURSE) == 0) { 388 dd = devfs_parent_dirent(de); 389 if (dd != NULL) 390 DEVFS_DE_HOLD(dd); 391 if (de->de_flags & DE_USER) { 392 KASSERT(dd != NULL, ("devfs_delete: NULL dd")); 393 devfs_dir_unref_de(dm, dd); 394 } 395 } else 396 dd = NULL; 397 398 mtx_lock(&devfs_de_interlock); 399 vp = de->de_vnode; 400 if (vp != NULL) { 401 VI_LOCK(vp); 402 mtx_unlock(&devfs_de_interlock); 403 vholdl(vp); 404 sx_unlock(&dm->dm_lock); 405 if ((flags & DEVFS_DEL_VNLOCKED) == 0) 406 vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 407 else 408 VI_UNLOCK(vp); 409 vgone(vp); 410 if ((flags & DEVFS_DEL_VNLOCKED) == 0) 411 VOP_UNLOCK(vp); 412 vdrop(vp); 413 sx_xlock(&dm->dm_lock); 414 } else 415 mtx_unlock(&devfs_de_interlock); 416 if (de->de_symlink) { 417 free(de->de_symlink, M_DEVFS); 418 de->de_symlink = NULL; 419 } 420 #ifdef MAC 421 mac_devfs_destroy(de); 422 #endif 423 if (de->de_inode > DEVFS_ROOTINO) { 424 devfs_free_cdp_inode(de->de_inode); 425 de->de_inode = 0; 426 } 427 if (DEVFS_DE_DROP(de)) 428 devfs_dirent_free(de); 429 430 if (dd != NULL) { 431 if (DEVFS_DE_DROP(dd)) 432 devfs_dirent_free(dd); 433 else 434 devfs_rmdir_empty(dm, dd); 435 } 436 } 437 438 /* 439 * Called on unmount. 440 * Recursively removes the entire tree. 441 * The caller needs to hold the dm for the duration of the call. 442 */ 443 444 static void 445 devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd) 446 { 447 struct devfs_dirent *de; 448 449 sx_assert(&dm->dm_lock, SX_XLOCKED); 450 451 DEVFS_DE_HOLD(dd); 452 for (;;) { 453 /* 454 * Use TAILQ_LAST() to remove "." and ".." last. 455 * We might need ".." to resolve a path in 456 * devfs_dir_unref_de(). 457 */ 458 de = TAILQ_LAST(&dd->de_dlist, devfs_dlist_head); 459 if (de == NULL) 460 break; 461 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 462 if (de->de_flags & DE_USER) 463 devfs_dir_unref_de(dm, dd); 464 if (de->de_flags & (DE_DOT | DE_DOTDOT)) 465 devfs_delete(dm, de, DEVFS_DEL_NORECURSE); 466 else if (de->de_dirent->d_type == DT_DIR) 467 devfs_purge(dm, de); 468 else 469 devfs_delete(dm, de, DEVFS_DEL_NORECURSE); 470 } 471 if (DEVFS_DE_DROP(dd)) 472 devfs_dirent_free(dd); 473 else if ((dd->de_flags & DE_DOOMED) == 0) 474 devfs_delete(dm, dd, DEVFS_DEL_NORECURSE); 475 } 476 477 /* 478 * Each cdev_priv has an array of pointers to devfs_dirent which is indexed 479 * by the mount points dm_idx. 480 * This function extends the array when necessary, taking into account that 481 * the default array is 1 element and not malloc'ed. 482 */ 483 static void 484 devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm) 485 { 486 struct devfs_dirent **dep; 487 int siz; 488 489 siz = (dm->dm_idx + 1) * sizeof *dep; 490 dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO); 491 dev_lock(); 492 if (dm->dm_idx <= cdp->cdp_maxdirent) { 493 /* We got raced */ 494 dev_unlock(); 495 free(dep, M_DEVFS2); 496 return; 497 } 498 memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep); 499 if (cdp->cdp_maxdirent > 0) 500 free(cdp->cdp_dirents, M_DEVFS2); 501 cdp->cdp_dirents = dep; 502 /* 503 * XXX: if malloc told us how much we actually got this could 504 * XXX: be optimized. 505 */ 506 cdp->cdp_maxdirent = dm->dm_idx; 507 dev_unlock(); 508 } 509 510 /* 511 * The caller needs to hold the dm for the duration of the call. 512 */ 513 static int 514 devfs_populate_loop(struct devfs_mount *dm, int cleanup) 515 { 516 struct cdev_priv *cdp; 517 struct devfs_dirent *de; 518 struct devfs_dirent *dd, *dt; 519 struct cdev *pdev; 520 int de_flags, depth, j; 521 char *q, *s; 522 523 sx_assert(&dm->dm_lock, SX_XLOCKED); 524 dev_lock(); 525 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 526 527 KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents")); 528 529 /* 530 * If we are unmounting, or the device has been destroyed, 531 * clean up our dirent. 532 */ 533 if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) && 534 dm->dm_idx <= cdp->cdp_maxdirent && 535 cdp->cdp_dirents[dm->dm_idx] != NULL) { 536 de = cdp->cdp_dirents[dm->dm_idx]; 537 cdp->cdp_dirents[dm->dm_idx] = NULL; 538 KASSERT(cdp == de->de_cdp, 539 ("%s %d %s %p %p", __func__, __LINE__, 540 cdp->cdp_c.si_name, cdp, de->de_cdp)); 541 KASSERT(de->de_dir != NULL, ("Null de->de_dir")); 542 dev_unlock(); 543 544 TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list); 545 de->de_cdp = NULL; 546 de->de_inode = 0; 547 devfs_delete(dm, de, 0); 548 dev_lock(); 549 cdp->cdp_inuse--; 550 dev_unlock(); 551 return (1); 552 } 553 /* 554 * GC any lingering devices 555 */ 556 if (!(cdp->cdp_flags & CDP_ACTIVE)) { 557 if (cdp->cdp_inuse > 0) 558 continue; 559 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); 560 dev_unlock(); 561 dev_rel(&cdp->cdp_c); 562 return (1); 563 } 564 /* 565 * Don't create any new dirents if we are unmounting 566 */ 567 if (cleanup) 568 continue; 569 KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!")); 570 571 if (dm->dm_idx <= cdp->cdp_maxdirent && 572 cdp->cdp_dirents[dm->dm_idx] != NULL) { 573 de = cdp->cdp_dirents[dm->dm_idx]; 574 KASSERT(cdp == de->de_cdp, ("inconsistent cdp")); 575 continue; 576 } 577 578 579 cdp->cdp_inuse++; 580 dev_unlock(); 581 582 if (dm->dm_idx > cdp->cdp_maxdirent) 583 devfs_metoo(cdp, dm); 584 585 dd = dm->dm_rootdir; 586 s = cdp->cdp_c.si_name; 587 for (;;) { 588 for (q = s; *q != '/' && *q != '\0'; q++) 589 continue; 590 if (*q != '/') 591 break; 592 de = devfs_find(dd, s, q - s, 0); 593 if (de == NULL) 594 de = devfs_vmkdir(dm, s, q - s, dd, 0); 595 else if (de->de_dirent->d_type == DT_LNK) { 596 de = devfs_find(dd, s, q - s, DT_DIR); 597 if (de == NULL) 598 de = devfs_vmkdir(dm, s, q - s, dd, 0); 599 de->de_flags |= DE_COVERED; 600 } 601 s = q + 1; 602 dd = de; 603 KASSERT(dd->de_dirent->d_type == DT_DIR && 604 (dd->de_flags & (DE_DOT | DE_DOTDOT)) == 0, 605 ("%s: invalid directory (si_name=%s)", 606 __func__, cdp->cdp_c.si_name)); 607 608 } 609 de_flags = 0; 610 de = devfs_find(dd, s, q - s, DT_LNK); 611 if (de != NULL) 612 de_flags |= DE_COVERED; 613 614 de = devfs_newdirent(s, q - s); 615 if (cdp->cdp_c.si_flags & SI_ALIAS) { 616 de->de_uid = 0; 617 de->de_gid = 0; 618 de->de_mode = 0755; 619 de->de_dirent->d_type = DT_LNK; 620 pdev = cdp->cdp_c.si_parent; 621 dt = dd; 622 depth = 0; 623 while (dt != dm->dm_rootdir && 624 (dt = devfs_parent_dirent(dt)) != NULL) 625 depth++; 626 j = depth * 3 + strlen(pdev->si_name) + 1; 627 de->de_symlink = malloc(j, M_DEVFS, M_WAITOK); 628 de->de_symlink[0] = 0; 629 while (depth-- > 0) 630 strcat(de->de_symlink, "../"); 631 strcat(de->de_symlink, pdev->si_name); 632 } else { 633 de->de_uid = cdp->cdp_c.si_uid; 634 de->de_gid = cdp->cdp_c.si_gid; 635 de->de_mode = cdp->cdp_c.si_mode; 636 de->de_dirent->d_type = DT_CHR; 637 } 638 de->de_flags |= de_flags; 639 de->de_inode = cdp->cdp_inode; 640 de->de_cdp = cdp; 641 #ifdef MAC 642 mac_devfs_create_device(cdp->cdp_c.si_cred, dm->dm_mount, 643 &cdp->cdp_c, de); 644 #endif 645 de->de_dir = dd; 646 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); 647 devfs_rules_apply(dm, de); 648 dev_lock(); 649 /* XXX: could check that cdp is still active here */ 650 KASSERT(cdp->cdp_dirents[dm->dm_idx] == NULL, 651 ("%s %d\n", __func__, __LINE__)); 652 cdp->cdp_dirents[dm->dm_idx] = de; 653 KASSERT(de->de_cdp != (void *)0xdeadc0de, 654 ("%s %d\n", __func__, __LINE__)); 655 dev_unlock(); 656 return (1); 657 } 658 dev_unlock(); 659 return (0); 660 } 661 662 /* 663 * The caller needs to hold the dm for the duration of the call. 664 */ 665 void 666 devfs_populate(struct devfs_mount *dm) 667 { 668 unsigned gen; 669 670 sx_assert(&dm->dm_lock, SX_XLOCKED); 671 gen = devfs_generation; 672 if (dm->dm_generation == gen) 673 return; 674 while (devfs_populate_loop(dm, 0)) 675 continue; 676 dm->dm_generation = gen; 677 } 678 679 /* 680 * The caller needs to hold the dm for the duration of the call. 681 */ 682 void 683 devfs_cleanup(struct devfs_mount *dm) 684 { 685 686 sx_assert(&dm->dm_lock, SX_XLOCKED); 687 while (devfs_populate_loop(dm, 1)) 688 continue; 689 devfs_purge(dm, dm->dm_rootdir); 690 } 691 692 /* 693 * devfs_create() and devfs_destroy() are called from kern_conf.c and 694 * in both cases the devlock() mutex is held, so no further locking 695 * is necessary and no sleeping allowed. 696 */ 697 698 void 699 devfs_create(struct cdev *dev) 700 { 701 struct cdev_priv *cdp; 702 703 mtx_assert(&devmtx, MA_OWNED); 704 cdp = cdev2priv(dev); 705 cdp->cdp_flags |= CDP_ACTIVE; 706 cdp->cdp_inode = alloc_unrl(devfs_inos); 707 dev_refl(dev); 708 TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list); 709 devfs_generation++; 710 } 711 712 void 713 devfs_destroy(struct cdev *dev) 714 { 715 struct cdev_priv *cdp; 716 717 mtx_assert(&devmtx, MA_OWNED); 718 cdp = cdev2priv(dev); 719 cdp->cdp_flags &= ~CDP_ACTIVE; 720 devfs_generation++; 721 } 722 723 ino_t 724 devfs_alloc_cdp_inode(void) 725 { 726 727 return (alloc_unr(devfs_inos)); 728 } 729 730 void 731 devfs_free_cdp_inode(ino_t ino) 732 { 733 734 if (ino > 0) 735 free_unr(devfs_inos, ino); 736 } 737 738 static void 739 devfs_devs_init(void *junk __unused) 740 { 741 742 devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx); 743 } 744 745 SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL); 746