1 /*- 2 * Copyright (c) 2000-2004 3 * Poul-Henning Kamp. All rights reserved. 4 * Copyright (c) 1989, 1992-1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95 32 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vnops.c 1.43 33 * 34 * $FreeBSD$ 35 */ 36 37 /* 38 * TODO: 39 * mkdir: want it ? 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/conf.h> 45 #include <sys/dirent.h> 46 #include <sys/fcntl.h> 47 #include <sys/file.h> 48 #include <sys/filedesc.h> 49 #include <sys/filio.h> 50 #include <sys/jail.h> 51 #include <sys/kernel.h> 52 #include <sys/lock.h> 53 #include <sys/malloc.h> 54 #include <sys/mman.h> 55 #include <sys/mount.h> 56 #include <sys/namei.h> 57 #include <sys/priv.h> 58 #include <sys/proc.h> 59 #include <sys/stat.h> 60 #include <sys/sx.h> 61 #include <sys/sysctl.h> 62 #include <sys/time.h> 63 #include <sys/ttycom.h> 64 #include <sys/unistd.h> 65 #include <sys/vnode.h> 66 67 static struct vop_vector devfs_vnodeops; 68 static struct vop_vector devfs_specops; 69 static struct fileops devfs_ops_f; 70 71 #include <fs/devfs/devfs.h> 72 #include <fs/devfs/devfs_int.h> 73 74 #include <security/mac/mac_framework.h> 75 76 #include <vm/vm.h> 77 #include <vm/vm_extern.h> 78 #include <vm/vm_object.h> 79 80 static MALLOC_DEFINE(M_CDEVPDATA, "DEVFSP", "Metainfo for cdev-fp data"); 81 82 struct mtx devfs_de_interlock; 83 MTX_SYSINIT(devfs_de_interlock, &devfs_de_interlock, "devfs interlock", MTX_DEF); 84 struct sx clone_drain_lock; 85 SX_SYSINIT(clone_drain_lock, &clone_drain_lock, "clone events drain lock"); 86 struct mtx cdevpriv_mtx; 87 MTX_SYSINIT(cdevpriv_mtx, &cdevpriv_mtx, "cdevpriv lock", MTX_DEF); 88 89 SYSCTL_DECL(_vfs_devfs); 90 91 static int devfs_dotimes; 92 SYSCTL_INT(_vfs_devfs, OID_AUTO, dotimes, CTLFLAG_RW, 93 &devfs_dotimes, 0, "Update timestamps on DEVFS with default precision"); 94 95 /* 96 * Update devfs node timestamp. Note that updates are unlocked and 97 * stat(2) could see partially updated times. 98 */ 99 static void 100 devfs_timestamp(struct timespec *tsp) 101 { 102 time_t ts; 103 104 if (devfs_dotimes) { 105 vfs_timestamp(tsp); 106 } else { 107 ts = time_second; 108 if (tsp->tv_sec != ts) { 109 tsp->tv_sec = ts; 110 tsp->tv_nsec = 0; 111 } 112 } 113 } 114 115 static int 116 devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp, 117 int *ref) 118 { 119 120 *dswp = devvn_refthread(fp->f_vnode, devp, ref); 121 if (*devp != fp->f_data) { 122 if (*dswp != NULL) 123 dev_relthread(*devp, *ref); 124 return (ENXIO); 125 } 126 KASSERT((*devp)->si_refcount > 0, 127 ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp))); 128 if (*dswp == NULL) 129 return (ENXIO); 130 curthread->td_fpop = fp; 131 return (0); 132 } 133 134 int 135 devfs_get_cdevpriv(void **datap) 136 { 137 struct file *fp; 138 struct cdev_privdata *p; 139 int error; 140 141 fp = curthread->td_fpop; 142 if (fp == NULL) 143 return (EBADF); 144 p = fp->f_cdevpriv; 145 if (p != NULL) { 146 error = 0; 147 *datap = p->cdpd_data; 148 } else 149 error = ENOENT; 150 return (error); 151 } 152 153 int 154 devfs_set_cdevpriv(void *priv, d_priv_dtor_t *priv_dtr) 155 { 156 struct file *fp; 157 struct cdev_priv *cdp; 158 struct cdev_privdata *p; 159 int error; 160 161 fp = curthread->td_fpop; 162 if (fp == NULL) 163 return (ENOENT); 164 cdp = cdev2priv((struct cdev *)fp->f_data); 165 p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK); 166 p->cdpd_data = priv; 167 p->cdpd_dtr = priv_dtr; 168 p->cdpd_fp = fp; 169 mtx_lock(&cdevpriv_mtx); 170 if (fp->f_cdevpriv == NULL) { 171 LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list); 172 fp->f_cdevpriv = p; 173 mtx_unlock(&cdevpriv_mtx); 174 error = 0; 175 } else { 176 mtx_unlock(&cdevpriv_mtx); 177 free(p, M_CDEVPDATA); 178 error = EBUSY; 179 } 180 return (error); 181 } 182 183 void 184 devfs_destroy_cdevpriv(struct cdev_privdata *p) 185 { 186 187 mtx_assert(&cdevpriv_mtx, MA_OWNED); 188 KASSERT(p->cdpd_fp->f_cdevpriv == p, 189 ("devfs_destoy_cdevpriv %p != %p", p->cdpd_fp->f_cdevpriv, p)); 190 p->cdpd_fp->f_cdevpriv = NULL; 191 LIST_REMOVE(p, cdpd_list); 192 mtx_unlock(&cdevpriv_mtx); 193 (p->cdpd_dtr)(p->cdpd_data); 194 free(p, M_CDEVPDATA); 195 } 196 197 static void 198 devfs_fpdrop(struct file *fp) 199 { 200 struct cdev_privdata *p; 201 202 mtx_lock(&cdevpriv_mtx); 203 if ((p = fp->f_cdevpriv) == NULL) { 204 mtx_unlock(&cdevpriv_mtx); 205 return; 206 } 207 devfs_destroy_cdevpriv(p); 208 } 209 210 void 211 devfs_clear_cdevpriv(void) 212 { 213 struct file *fp; 214 215 fp = curthread->td_fpop; 216 if (fp == NULL) 217 return; 218 devfs_fpdrop(fp); 219 } 220 221 /* 222 * On success devfs_populate_vp() returns with dmp->dm_lock held. 223 */ 224 static int 225 devfs_populate_vp(struct vnode *vp) 226 { 227 struct devfs_dirent *de; 228 struct devfs_mount *dmp; 229 int locked; 230 231 ASSERT_VOP_LOCKED(vp, "devfs_populate_vp"); 232 233 dmp = VFSTODEVFS(vp->v_mount); 234 locked = VOP_ISLOCKED(vp); 235 236 sx_xlock(&dmp->dm_lock); 237 DEVFS_DMP_HOLD(dmp); 238 239 /* Can't call devfs_populate() with the vnode lock held. */ 240 VOP_UNLOCK(vp, 0); 241 devfs_populate(dmp); 242 243 sx_xunlock(&dmp->dm_lock); 244 vn_lock(vp, locked | LK_RETRY); 245 sx_xlock(&dmp->dm_lock); 246 if (DEVFS_DMP_DROP(dmp)) { 247 sx_xunlock(&dmp->dm_lock); 248 devfs_unmount_final(dmp); 249 return (ERESTART); 250 } 251 if ((vp->v_iflag & VI_DOOMED) != 0) { 252 sx_xunlock(&dmp->dm_lock); 253 return (ERESTART); 254 } 255 de = vp->v_data; 256 KASSERT(de != NULL, 257 ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed")); 258 if ((de->de_flags & DE_DOOMED) != 0) { 259 sx_xunlock(&dmp->dm_lock); 260 return (ERESTART); 261 } 262 263 return (0); 264 } 265 266 static int 267 devfs_vptocnp(struct vop_vptocnp_args *ap) 268 { 269 struct vnode *vp = ap->a_vp; 270 struct vnode **dvp = ap->a_vpp; 271 struct devfs_mount *dmp; 272 char *buf = ap->a_buf; 273 int *buflen = ap->a_buflen; 274 struct devfs_dirent *dd, *de; 275 int i, error; 276 277 dmp = VFSTODEVFS(vp->v_mount); 278 279 error = devfs_populate_vp(vp); 280 if (error != 0) 281 return (error); 282 283 i = *buflen; 284 dd = vp->v_data; 285 286 if (vp->v_type == VCHR) { 287 i -= strlen(dd->de_cdp->cdp_c.si_name); 288 if (i < 0) { 289 error = ENOMEM; 290 goto finished; 291 } 292 bcopy(dd->de_cdp->cdp_c.si_name, buf + i, 293 strlen(dd->de_cdp->cdp_c.si_name)); 294 de = dd->de_dir; 295 } else if (vp->v_type == VDIR) { 296 if (dd == dmp->dm_rootdir) { 297 *dvp = vp; 298 vref(*dvp); 299 goto finished; 300 } 301 i -= dd->de_dirent->d_namlen; 302 if (i < 0) { 303 error = ENOMEM; 304 goto finished; 305 } 306 bcopy(dd->de_dirent->d_name, buf + i, 307 dd->de_dirent->d_namlen); 308 de = dd; 309 } else { 310 error = ENOENT; 311 goto finished; 312 } 313 *buflen = i; 314 de = devfs_parent_dirent(de); 315 if (de == NULL) { 316 error = ENOENT; 317 goto finished; 318 } 319 mtx_lock(&devfs_de_interlock); 320 *dvp = de->de_vnode; 321 if (*dvp != NULL) { 322 VI_LOCK(*dvp); 323 mtx_unlock(&devfs_de_interlock); 324 vholdl(*dvp); 325 VI_UNLOCK(*dvp); 326 vref(*dvp); 327 vdrop(*dvp); 328 } else { 329 mtx_unlock(&devfs_de_interlock); 330 error = ENOENT; 331 } 332 finished: 333 sx_xunlock(&dmp->dm_lock); 334 return (error); 335 } 336 337 /* 338 * Construct the fully qualified path name relative to the mountpoint. 339 * If a NULL cnp is provided, no '/' is appended to the resulting path. 340 */ 341 char * 342 devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd, 343 struct componentname *cnp) 344 { 345 int i; 346 struct devfs_dirent *de; 347 348 sx_assert(&dmp->dm_lock, SA_LOCKED); 349 350 i = SPECNAMELEN; 351 buf[i] = '\0'; 352 if (cnp != NULL) 353 i -= cnp->cn_namelen; 354 if (i < 0) 355 return (NULL); 356 if (cnp != NULL) 357 bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen); 358 de = dd; 359 while (de != dmp->dm_rootdir) { 360 if (cnp != NULL || i < SPECNAMELEN) { 361 i--; 362 if (i < 0) 363 return (NULL); 364 buf[i] = '/'; 365 } 366 i -= de->de_dirent->d_namlen; 367 if (i < 0) 368 return (NULL); 369 bcopy(de->de_dirent->d_name, buf + i, 370 de->de_dirent->d_namlen); 371 de = devfs_parent_dirent(de); 372 if (de == NULL) 373 return (NULL); 374 } 375 return (buf + i); 376 } 377 378 static int 379 devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp, 380 struct devfs_dirent *de) 381 { 382 int not_found; 383 384 not_found = 0; 385 if (de->de_flags & DE_DOOMED) 386 not_found = 1; 387 if (DEVFS_DE_DROP(de)) { 388 KASSERT(not_found == 1, ("DEVFS de dropped but not doomed")); 389 devfs_dirent_free(de); 390 } 391 if (DEVFS_DMP_DROP(dmp)) { 392 KASSERT(not_found == 1, 393 ("DEVFS mount struct freed before dirent")); 394 not_found = 2; 395 sx_xunlock(&dmp->dm_lock); 396 devfs_unmount_final(dmp); 397 } 398 if (not_found == 1 || (drop_dm_lock && not_found != 2)) 399 sx_unlock(&dmp->dm_lock); 400 return (not_found); 401 } 402 403 static void 404 devfs_insmntque_dtr(struct vnode *vp, void *arg) 405 { 406 struct devfs_dirent *de; 407 408 de = (struct devfs_dirent *)arg; 409 mtx_lock(&devfs_de_interlock); 410 vp->v_data = NULL; 411 de->de_vnode = NULL; 412 mtx_unlock(&devfs_de_interlock); 413 vgone(vp); 414 vput(vp); 415 } 416 417 /* 418 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops 419 * it on return. 420 */ 421 int 422 devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode, 423 struct vnode **vpp) 424 { 425 int error; 426 struct vnode *vp; 427 struct cdev *dev; 428 struct devfs_mount *dmp; 429 struct cdevsw *dsw; 430 431 dmp = VFSTODEVFS(mp); 432 if (de->de_flags & DE_DOOMED) { 433 sx_xunlock(&dmp->dm_lock); 434 return (ENOENT); 435 } 436 loop: 437 DEVFS_DE_HOLD(de); 438 DEVFS_DMP_HOLD(dmp); 439 mtx_lock(&devfs_de_interlock); 440 vp = de->de_vnode; 441 if (vp != NULL) { 442 VI_LOCK(vp); 443 mtx_unlock(&devfs_de_interlock); 444 sx_xunlock(&dmp->dm_lock); 445 vget(vp, lockmode | LK_INTERLOCK | LK_RETRY, curthread); 446 sx_xlock(&dmp->dm_lock); 447 if (devfs_allocv_drop_refs(0, dmp, de)) { 448 vput(vp); 449 return (ENOENT); 450 } 451 else if ((vp->v_iflag & VI_DOOMED) != 0) { 452 mtx_lock(&devfs_de_interlock); 453 if (de->de_vnode == vp) { 454 de->de_vnode = NULL; 455 vp->v_data = NULL; 456 } 457 mtx_unlock(&devfs_de_interlock); 458 vput(vp); 459 goto loop; 460 } 461 sx_xunlock(&dmp->dm_lock); 462 *vpp = vp; 463 return (0); 464 } 465 mtx_unlock(&devfs_de_interlock); 466 if (de->de_dirent->d_type == DT_CHR) { 467 if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) { 468 devfs_allocv_drop_refs(1, dmp, de); 469 return (ENOENT); 470 } 471 dev = &de->de_cdp->cdp_c; 472 } else { 473 dev = NULL; 474 } 475 error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp); 476 if (error != 0) { 477 devfs_allocv_drop_refs(1, dmp, de); 478 printf("devfs_allocv: failed to allocate new vnode\n"); 479 return (error); 480 } 481 482 if (de->de_dirent->d_type == DT_CHR) { 483 vp->v_type = VCHR; 484 VI_LOCK(vp); 485 dev_lock(); 486 dev_refl(dev); 487 /* XXX: v_rdev should be protect by vnode lock */ 488 vp->v_rdev = dev; 489 KASSERT(vp->v_usecount == 1, 490 ("%s %d (%d)\n", __func__, __LINE__, vp->v_usecount)); 491 dev->si_usecount += vp->v_usecount; 492 /* Special casing of ttys for deadfs. Probably redundant. */ 493 dsw = dev->si_devsw; 494 if (dsw != NULL && (dsw->d_flags & D_TTY) != 0) 495 vp->v_vflag |= VV_ISTTY; 496 dev_unlock(); 497 VI_UNLOCK(vp); 498 if ((dev->si_flags & SI_ETERNAL) != 0) 499 vp->v_vflag |= VV_ETERNALDEV; 500 vp->v_op = &devfs_specops; 501 } else if (de->de_dirent->d_type == DT_DIR) { 502 vp->v_type = VDIR; 503 } else if (de->de_dirent->d_type == DT_LNK) { 504 vp->v_type = VLNK; 505 } else { 506 vp->v_type = VBAD; 507 } 508 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS); 509 VN_LOCK_ASHARE(vp); 510 mtx_lock(&devfs_de_interlock); 511 vp->v_data = de; 512 de->de_vnode = vp; 513 mtx_unlock(&devfs_de_interlock); 514 error = insmntque1(vp, mp, devfs_insmntque_dtr, de); 515 if (error != 0) { 516 (void) devfs_allocv_drop_refs(1, dmp, de); 517 return (error); 518 } 519 if (devfs_allocv_drop_refs(0, dmp, de)) { 520 vput(vp); 521 return (ENOENT); 522 } 523 #ifdef MAC 524 mac_devfs_vnode_associate(mp, de, vp); 525 #endif 526 sx_xunlock(&dmp->dm_lock); 527 *vpp = vp; 528 return (0); 529 } 530 531 static int 532 devfs_access(struct vop_access_args *ap) 533 { 534 struct vnode *vp = ap->a_vp; 535 struct devfs_dirent *de; 536 struct proc *p; 537 int error; 538 539 de = vp->v_data; 540 if (vp->v_type == VDIR) 541 de = de->de_dir; 542 543 error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid, 544 ap->a_accmode, ap->a_cred, NULL); 545 if (error == 0) 546 return (0); 547 if (error != EACCES) 548 return (error); 549 p = ap->a_td->td_proc; 550 /* We do, however, allow access to the controlling terminal */ 551 PROC_LOCK(p); 552 if (!(p->p_flag & P_CONTROLT)) { 553 PROC_UNLOCK(p); 554 return (error); 555 } 556 if (p->p_session->s_ttydp == de->de_cdp) 557 error = 0; 558 PROC_UNLOCK(p); 559 return (error); 560 } 561 562 _Static_assert(((FMASK | FCNTLFLAGS) & (FLASTCLOSE | FREVOKE)) == 0, 563 "devfs-only flag reuse failed"); 564 565 static int 566 devfs_close(struct vop_close_args *ap) 567 { 568 struct vnode *vp = ap->a_vp, *oldvp; 569 struct thread *td = ap->a_td; 570 struct proc *p; 571 struct cdev *dev = vp->v_rdev; 572 struct cdevsw *dsw; 573 int dflags, error, ref, vp_locked; 574 575 /* 576 * XXX: Don't call d_close() if we were called because of 577 * XXX: insmntque1() failure. 578 */ 579 if (vp->v_data == NULL) 580 return (0); 581 582 /* 583 * Hack: a tty device that is a controlling terminal 584 * has a reference from the session structure. 585 * We cannot easily tell that a character device is 586 * a controlling terminal, unless it is the closing 587 * process' controlling terminal. In that case, 588 * if the reference count is 2 (this last descriptor 589 * plus the session), release the reference from the session. 590 */ 591 if (td != NULL) { 592 p = td->td_proc; 593 PROC_LOCK(p); 594 if (vp == p->p_session->s_ttyvp) { 595 PROC_UNLOCK(p); 596 oldvp = NULL; 597 sx_xlock(&proctree_lock); 598 if (vp == p->p_session->s_ttyvp) { 599 SESS_LOCK(p->p_session); 600 VI_LOCK(vp); 601 if (count_dev(dev) == 2 && 602 (vp->v_iflag & VI_DOOMED) == 0) { 603 p->p_session->s_ttyvp = NULL; 604 p->p_session->s_ttydp = NULL; 605 oldvp = vp; 606 } 607 VI_UNLOCK(vp); 608 SESS_UNLOCK(p->p_session); 609 } 610 sx_xunlock(&proctree_lock); 611 if (oldvp != NULL) 612 vrele(oldvp); 613 } else 614 PROC_UNLOCK(p); 615 } 616 /* 617 * We do not want to really close the device if it 618 * is still in use unless we are trying to close it 619 * forcibly. Since every use (buffer, vnode, swap, cmap) 620 * holds a reference to the vnode, and because we mark 621 * any other vnodes that alias this device, when the 622 * sum of the reference counts on all the aliased 623 * vnodes descends to one, we are on last close. 624 */ 625 dsw = dev_refthread(dev, &ref); 626 if (dsw == NULL) 627 return (ENXIO); 628 dflags = 0; 629 VI_LOCK(vp); 630 if (vp->v_iflag & VI_DOOMED) { 631 /* Forced close. */ 632 dflags |= FREVOKE | FNONBLOCK; 633 } else if (dsw->d_flags & D_TRACKCLOSE) { 634 /* Keep device updated on status. */ 635 } else if (count_dev(dev) > 1) { 636 VI_UNLOCK(vp); 637 dev_relthread(dev, ref); 638 return (0); 639 } 640 if (count_dev(dev) == 1) 641 dflags |= FLASTCLOSE; 642 vholdl(vp); 643 VI_UNLOCK(vp); 644 vp_locked = VOP_ISLOCKED(vp); 645 VOP_UNLOCK(vp, 0); 646 KASSERT(dev->si_refcount > 0, 647 ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev))); 648 error = dsw->d_close(dev, ap->a_fflag | dflags, S_IFCHR, td); 649 dev_relthread(dev, ref); 650 vn_lock(vp, vp_locked | LK_RETRY); 651 vdrop(vp); 652 return (error); 653 } 654 655 static int 656 devfs_close_f(struct file *fp, struct thread *td) 657 { 658 int error; 659 struct file *fpop; 660 661 /* 662 * NB: td may be NULL if this descriptor is closed due to 663 * garbage collection from a closed UNIX domain socket. 664 */ 665 fpop = curthread->td_fpop; 666 curthread->td_fpop = fp; 667 error = vnops.fo_close(fp, td); 668 curthread->td_fpop = fpop; 669 670 /* 671 * The f_cdevpriv cannot be assigned non-NULL value while we 672 * are destroying the file. 673 */ 674 if (fp->f_cdevpriv != NULL) 675 devfs_fpdrop(fp); 676 return (error); 677 } 678 679 static int 680 devfs_getattr(struct vop_getattr_args *ap) 681 { 682 struct vnode *vp = ap->a_vp; 683 struct vattr *vap = ap->a_vap; 684 struct devfs_dirent *de; 685 struct devfs_mount *dmp; 686 struct cdev *dev; 687 struct timeval boottime; 688 int error; 689 690 error = devfs_populate_vp(vp); 691 if (error != 0) 692 return (error); 693 694 dmp = VFSTODEVFS(vp->v_mount); 695 sx_xunlock(&dmp->dm_lock); 696 697 de = vp->v_data; 698 KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp)); 699 if (vp->v_type == VDIR) { 700 de = de->de_dir; 701 KASSERT(de != NULL, 702 ("Null dir dirent in devfs_getattr vp=%p", vp)); 703 } 704 vap->va_uid = de->de_uid; 705 vap->va_gid = de->de_gid; 706 vap->va_mode = de->de_mode; 707 if (vp->v_type == VLNK) 708 vap->va_size = strlen(de->de_symlink); 709 else if (vp->v_type == VDIR) 710 vap->va_size = vap->va_bytes = DEV_BSIZE; 711 else 712 vap->va_size = 0; 713 if (vp->v_type != VDIR) 714 vap->va_bytes = 0; 715 vap->va_blocksize = DEV_BSIZE; 716 vap->va_type = vp->v_type; 717 718 getboottime(&boottime); 719 #define fix(aa) \ 720 do { \ 721 if ((aa).tv_sec <= 3600) { \ 722 (aa).tv_sec = boottime.tv_sec; \ 723 (aa).tv_nsec = boottime.tv_usec * 1000; \ 724 } \ 725 } while (0) 726 727 if (vp->v_type != VCHR) { 728 fix(de->de_atime); 729 vap->va_atime = de->de_atime; 730 fix(de->de_mtime); 731 vap->va_mtime = de->de_mtime; 732 fix(de->de_ctime); 733 vap->va_ctime = de->de_ctime; 734 } else { 735 dev = vp->v_rdev; 736 fix(dev->si_atime); 737 vap->va_atime = dev->si_atime; 738 fix(dev->si_mtime); 739 vap->va_mtime = dev->si_mtime; 740 fix(dev->si_ctime); 741 vap->va_ctime = dev->si_ctime; 742 743 vap->va_rdev = cdev2priv(dev)->cdp_inode; 744 } 745 vap->va_gen = 0; 746 vap->va_flags = 0; 747 vap->va_filerev = 0; 748 vap->va_nlink = de->de_links; 749 vap->va_fileid = de->de_inode; 750 751 return (error); 752 } 753 754 /* ARGSUSED */ 755 static int 756 devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td) 757 { 758 struct file *fpop; 759 int error; 760 761 fpop = td->td_fpop; 762 td->td_fpop = fp; 763 error = vnops.fo_ioctl(fp, com, data, cred, td); 764 td->td_fpop = fpop; 765 return (error); 766 } 767 768 static int 769 devfs_ioctl(struct vop_ioctl_args *ap) 770 { 771 struct fiodgname_arg *fgn; 772 struct vnode *vpold, *vp; 773 struct cdevsw *dsw; 774 struct thread *td; 775 struct cdev *dev; 776 int error, ref, i; 777 const char *p; 778 u_long com; 779 780 vp = ap->a_vp; 781 com = ap->a_command; 782 td = ap->a_td; 783 784 dsw = devvn_refthread(vp, &dev, &ref); 785 if (dsw == NULL) 786 return (ENXIO); 787 KASSERT(dev->si_refcount > 0, 788 ("devfs: un-referenced struct cdev *(%s)", devtoname(dev))); 789 790 if (com == FIODTYPE) { 791 *(int *)ap->a_data = dsw->d_flags & D_TYPEMASK; 792 error = 0; 793 goto out; 794 } else if (com == FIODGNAME) { 795 fgn = ap->a_data; 796 p = devtoname(dev); 797 i = strlen(p) + 1; 798 if (i > fgn->len) 799 error = EINVAL; 800 else 801 error = copyout(p, fgn->buf, i); 802 goto out; 803 } 804 805 error = dsw->d_ioctl(dev, com, ap->a_data, ap->a_fflag, td); 806 807 out: 808 dev_relthread(dev, ref); 809 if (error == ENOIOCTL) 810 error = ENOTTY; 811 812 if (error == 0 && com == TIOCSCTTY) { 813 /* Do nothing if reassigning same control tty */ 814 sx_slock(&proctree_lock); 815 if (td->td_proc->p_session->s_ttyvp == vp) { 816 sx_sunlock(&proctree_lock); 817 return (0); 818 } 819 820 vpold = td->td_proc->p_session->s_ttyvp; 821 VREF(vp); 822 SESS_LOCK(td->td_proc->p_session); 823 td->td_proc->p_session->s_ttyvp = vp; 824 td->td_proc->p_session->s_ttydp = cdev2priv(dev); 825 SESS_UNLOCK(td->td_proc->p_session); 826 827 sx_sunlock(&proctree_lock); 828 829 /* Get rid of reference to old control tty */ 830 if (vpold) 831 vrele(vpold); 832 } 833 return (error); 834 } 835 836 /* ARGSUSED */ 837 static int 838 devfs_kqfilter_f(struct file *fp, struct knote *kn) 839 { 840 struct cdev *dev; 841 struct cdevsw *dsw; 842 int error, ref; 843 struct file *fpop; 844 struct thread *td; 845 846 td = curthread; 847 fpop = td->td_fpop; 848 error = devfs_fp_check(fp, &dev, &dsw, &ref); 849 if (error) 850 return (error); 851 error = dsw->d_kqfilter(dev, kn); 852 td->td_fpop = fpop; 853 dev_relthread(dev, ref); 854 return (error); 855 } 856 857 static inline int 858 devfs_prison_check(struct devfs_dirent *de, struct thread *td) 859 { 860 struct cdev_priv *cdp; 861 struct ucred *dcr; 862 struct proc *p; 863 int error; 864 865 cdp = de->de_cdp; 866 if (cdp == NULL) 867 return (0); 868 dcr = cdp->cdp_c.si_cred; 869 if (dcr == NULL) 870 return (0); 871 872 error = prison_check(td->td_ucred, dcr); 873 if (error == 0) 874 return (0); 875 /* We do, however, allow access to the controlling terminal */ 876 p = td->td_proc; 877 PROC_LOCK(p); 878 if (!(p->p_flag & P_CONTROLT)) { 879 PROC_UNLOCK(p); 880 return (error); 881 } 882 if (p->p_session->s_ttydp == cdp) 883 error = 0; 884 PROC_UNLOCK(p); 885 return (error); 886 } 887 888 static int 889 devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock) 890 { 891 struct componentname *cnp; 892 struct vnode *dvp, **vpp; 893 struct thread *td; 894 struct devfs_dirent *de, *dd; 895 struct devfs_dirent **dde; 896 struct devfs_mount *dmp; 897 struct cdev *cdev; 898 int error, flags, nameiop, dvplocked; 899 char specname[SPECNAMELEN + 1], *pname; 900 901 cnp = ap->a_cnp; 902 vpp = ap->a_vpp; 903 dvp = ap->a_dvp; 904 pname = cnp->cn_nameptr; 905 td = cnp->cn_thread; 906 flags = cnp->cn_flags; 907 nameiop = cnp->cn_nameiop; 908 dmp = VFSTODEVFS(dvp->v_mount); 909 dd = dvp->v_data; 910 *vpp = NULLVP; 911 912 if ((flags & ISLASTCN) && nameiop == RENAME) 913 return (EOPNOTSUPP); 914 915 if (dvp->v_type != VDIR) 916 return (ENOTDIR); 917 918 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT)) 919 return (EIO); 920 921 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td); 922 if (error) 923 return (error); 924 925 if (cnp->cn_namelen == 1 && *pname == '.') { 926 if ((flags & ISLASTCN) && nameiop != LOOKUP) 927 return (EINVAL); 928 *vpp = dvp; 929 VREF(dvp); 930 return (0); 931 } 932 933 if (flags & ISDOTDOT) { 934 if ((flags & ISLASTCN) && nameiop != LOOKUP) 935 return (EINVAL); 936 de = devfs_parent_dirent(dd); 937 if (de == NULL) 938 return (ENOENT); 939 dvplocked = VOP_ISLOCKED(dvp); 940 VOP_UNLOCK(dvp, 0); 941 error = devfs_allocv(de, dvp->v_mount, 942 cnp->cn_lkflags & LK_TYPE_MASK, vpp); 943 *dm_unlock = 0; 944 vn_lock(dvp, dvplocked | LK_RETRY); 945 return (error); 946 } 947 948 dd = dvp->v_data; 949 de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0); 950 while (de == NULL) { /* While(...) so we can use break */ 951 952 if (nameiop == DELETE) 953 return (ENOENT); 954 955 /* 956 * OK, we didn't have an entry for the name we were asked for 957 * so we try to see if anybody can create it on demand. 958 */ 959 pname = devfs_fqpn(specname, dmp, dd, cnp); 960 if (pname == NULL) 961 break; 962 963 cdev = NULL; 964 DEVFS_DMP_HOLD(dmp); 965 sx_xunlock(&dmp->dm_lock); 966 sx_slock(&clone_drain_lock); 967 EVENTHANDLER_INVOKE(dev_clone, 968 td->td_ucred, pname, strlen(pname), &cdev); 969 sx_sunlock(&clone_drain_lock); 970 971 if (cdev == NULL) 972 sx_xlock(&dmp->dm_lock); 973 else if (devfs_populate_vp(dvp) != 0) { 974 *dm_unlock = 0; 975 sx_xlock(&dmp->dm_lock); 976 if (DEVFS_DMP_DROP(dmp)) { 977 sx_xunlock(&dmp->dm_lock); 978 devfs_unmount_final(dmp); 979 } else 980 sx_xunlock(&dmp->dm_lock); 981 dev_rel(cdev); 982 return (ENOENT); 983 } 984 if (DEVFS_DMP_DROP(dmp)) { 985 *dm_unlock = 0; 986 sx_xunlock(&dmp->dm_lock); 987 devfs_unmount_final(dmp); 988 if (cdev != NULL) 989 dev_rel(cdev); 990 return (ENOENT); 991 } 992 993 if (cdev == NULL) 994 break; 995 996 dev_lock(); 997 dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx]; 998 if (dde != NULL && *dde != NULL) 999 de = *dde; 1000 dev_unlock(); 1001 dev_rel(cdev); 1002 break; 1003 } 1004 1005 if (de == NULL || de->de_flags & DE_WHITEOUT) { 1006 if ((nameiop == CREATE || nameiop == RENAME) && 1007 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) { 1008 cnp->cn_flags |= SAVENAME; 1009 return (EJUSTRETURN); 1010 } 1011 return (ENOENT); 1012 } 1013 1014 if (devfs_prison_check(de, td)) 1015 return (ENOENT); 1016 1017 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) { 1018 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); 1019 if (error) 1020 return (error); 1021 if (*vpp == dvp) { 1022 VREF(dvp); 1023 *vpp = dvp; 1024 return (0); 1025 } 1026 } 1027 error = devfs_allocv(de, dvp->v_mount, cnp->cn_lkflags & LK_TYPE_MASK, 1028 vpp); 1029 *dm_unlock = 0; 1030 return (error); 1031 } 1032 1033 static int 1034 devfs_lookup(struct vop_lookup_args *ap) 1035 { 1036 int j; 1037 struct devfs_mount *dmp; 1038 int dm_unlock; 1039 1040 if (devfs_populate_vp(ap->a_dvp) != 0) 1041 return (ENOTDIR); 1042 1043 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1044 dm_unlock = 1; 1045 j = devfs_lookupx(ap, &dm_unlock); 1046 if (dm_unlock == 1) 1047 sx_xunlock(&dmp->dm_lock); 1048 return (j); 1049 } 1050 1051 static int 1052 devfs_mknod(struct vop_mknod_args *ap) 1053 { 1054 struct componentname *cnp; 1055 struct vnode *dvp, **vpp; 1056 struct devfs_dirent *dd, *de; 1057 struct devfs_mount *dmp; 1058 int error; 1059 1060 /* 1061 * The only type of node we should be creating here is a 1062 * character device, for anything else return EOPNOTSUPP. 1063 */ 1064 if (ap->a_vap->va_type != VCHR) 1065 return (EOPNOTSUPP); 1066 dvp = ap->a_dvp; 1067 dmp = VFSTODEVFS(dvp->v_mount); 1068 1069 cnp = ap->a_cnp; 1070 vpp = ap->a_vpp; 1071 dd = dvp->v_data; 1072 1073 error = ENOENT; 1074 sx_xlock(&dmp->dm_lock); 1075 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 1076 if (cnp->cn_namelen != de->de_dirent->d_namlen) 1077 continue; 1078 if (de->de_dirent->d_type == DT_CHR && 1079 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0) 1080 continue; 1081 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 1082 de->de_dirent->d_namlen) != 0) 1083 continue; 1084 if (de->de_flags & DE_WHITEOUT) 1085 break; 1086 goto notfound; 1087 } 1088 if (de == NULL) 1089 goto notfound; 1090 de->de_flags &= ~DE_WHITEOUT; 1091 error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp); 1092 return (error); 1093 notfound: 1094 sx_xunlock(&dmp->dm_lock); 1095 return (error); 1096 } 1097 1098 /* ARGSUSED */ 1099 static int 1100 devfs_open(struct vop_open_args *ap) 1101 { 1102 struct thread *td = ap->a_td; 1103 struct vnode *vp = ap->a_vp; 1104 struct cdev *dev = vp->v_rdev; 1105 struct file *fp = ap->a_fp; 1106 int error, ref, vlocked; 1107 struct cdevsw *dsw; 1108 struct file *fpop; 1109 struct mtx *mtxp; 1110 1111 if (vp->v_type == VBLK) 1112 return (ENXIO); 1113 1114 if (dev == NULL) 1115 return (ENXIO); 1116 1117 /* Make this field valid before any I/O in d_open. */ 1118 if (dev->si_iosize_max == 0) 1119 dev->si_iosize_max = DFLTPHYS; 1120 1121 dsw = dev_refthread(dev, &ref); 1122 if (dsw == NULL) 1123 return (ENXIO); 1124 if (fp == NULL && dsw->d_fdopen != NULL) { 1125 dev_relthread(dev, ref); 1126 return (ENXIO); 1127 } 1128 1129 vlocked = VOP_ISLOCKED(vp); 1130 VOP_UNLOCK(vp, 0); 1131 1132 fpop = td->td_fpop; 1133 td->td_fpop = fp; 1134 if (fp != NULL) { 1135 fp->f_data = dev; 1136 fp->f_vnode = vp; 1137 } 1138 if (dsw->d_fdopen != NULL) 1139 error = dsw->d_fdopen(dev, ap->a_mode, td, fp); 1140 else 1141 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 1142 /* Clean up any cdevpriv upon error. */ 1143 if (error != 0) 1144 devfs_clear_cdevpriv(); 1145 td->td_fpop = fpop; 1146 1147 vn_lock(vp, vlocked | LK_RETRY); 1148 dev_relthread(dev, ref); 1149 if (error != 0) { 1150 if (error == ERESTART) 1151 error = EINTR; 1152 return (error); 1153 } 1154 1155 #if 0 /* /dev/console */ 1156 KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp")); 1157 #else 1158 if (fp == NULL) 1159 return (error); 1160 #endif 1161 if (fp->f_ops == &badfileops) 1162 finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f); 1163 mtxp = mtx_pool_find(mtxpool_sleep, fp); 1164 1165 /* 1166 * Hint to the dofilewrite() to not force the buffer draining 1167 * on the writer to the file. Most likely, the write would 1168 * not need normal buffers. 1169 */ 1170 mtx_lock(mtxp); 1171 fp->f_vnread_flags |= FDEVFS_VNODE; 1172 mtx_unlock(mtxp); 1173 return (error); 1174 } 1175 1176 static int 1177 devfs_pathconf(struct vop_pathconf_args *ap) 1178 { 1179 1180 switch (ap->a_name) { 1181 case _PC_MAX_CANON: 1182 if (ap->a_vp->v_vflag & VV_ISTTY) { 1183 *ap->a_retval = MAX_CANON; 1184 return (0); 1185 } 1186 return (EINVAL); 1187 case _PC_MAX_INPUT: 1188 if (ap->a_vp->v_vflag & VV_ISTTY) { 1189 *ap->a_retval = MAX_INPUT; 1190 return (0); 1191 } 1192 return (EINVAL); 1193 case _PC_VDISABLE: 1194 if (ap->a_vp->v_vflag & VV_ISTTY) { 1195 *ap->a_retval = _POSIX_VDISABLE; 1196 return (0); 1197 } 1198 return (EINVAL); 1199 case _PC_MAC_PRESENT: 1200 #ifdef MAC 1201 /* 1202 * If MAC is enabled, devfs automatically supports 1203 * trivial non-persistant label storage. 1204 */ 1205 *ap->a_retval = 1; 1206 #else 1207 *ap->a_retval = 0; 1208 #endif 1209 return (0); 1210 default: 1211 return (vop_stdpathconf(ap)); 1212 } 1213 /* NOTREACHED */ 1214 } 1215 1216 /* ARGSUSED */ 1217 static int 1218 devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td) 1219 { 1220 struct cdev *dev; 1221 struct cdevsw *dsw; 1222 int error, ref; 1223 struct file *fpop; 1224 1225 fpop = td->td_fpop; 1226 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1227 if (error != 0) { 1228 error = vnops.fo_poll(fp, events, cred, td); 1229 return (error); 1230 } 1231 error = dsw->d_poll(dev, events, td); 1232 td->td_fpop = fpop; 1233 dev_relthread(dev, ref); 1234 return(error); 1235 } 1236 1237 /* 1238 * Print out the contents of a special device vnode. 1239 */ 1240 static int 1241 devfs_print(struct vop_print_args *ap) 1242 { 1243 1244 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev)); 1245 return (0); 1246 } 1247 1248 static int 1249 devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred, 1250 int flags, struct thread *td) 1251 { 1252 struct cdev *dev; 1253 int ioflag, error, ref; 1254 ssize_t resid; 1255 struct cdevsw *dsw; 1256 struct file *fpop; 1257 1258 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1259 return (EINVAL); 1260 fpop = td->td_fpop; 1261 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1262 if (error != 0) { 1263 error = vnops.fo_read(fp, uio, cred, flags, td); 1264 return (error); 1265 } 1266 resid = uio->uio_resid; 1267 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT); 1268 if (ioflag & O_DIRECT) 1269 ioflag |= IO_DIRECT; 1270 1271 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1272 error = dsw->d_read(dev, uio, ioflag); 1273 if (uio->uio_resid != resid || (error == 0 && resid != 0)) 1274 devfs_timestamp(&dev->si_atime); 1275 td->td_fpop = fpop; 1276 dev_relthread(dev, ref); 1277 1278 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1279 return (error); 1280 } 1281 1282 static int 1283 devfs_readdir(struct vop_readdir_args *ap) 1284 { 1285 int error; 1286 struct uio *uio; 1287 struct dirent *dp; 1288 struct devfs_dirent *dd; 1289 struct devfs_dirent *de; 1290 struct devfs_mount *dmp; 1291 off_t off; 1292 int *tmp_ncookies = NULL; 1293 1294 if (ap->a_vp->v_type != VDIR) 1295 return (ENOTDIR); 1296 1297 uio = ap->a_uio; 1298 if (uio->uio_offset < 0) 1299 return (EINVAL); 1300 1301 /* 1302 * XXX: This is a temporary hack to get around this filesystem not 1303 * supporting cookies. We store the location of the ncookies pointer 1304 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent() 1305 * and set the number of cookies to 0. We then set the pointer to 1306 * NULL so that vfs_read_dirent doesn't try to call realloc() on 1307 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies 1308 * pointer to its original location before returning to the caller. 1309 */ 1310 if (ap->a_ncookies != NULL) { 1311 tmp_ncookies = ap->a_ncookies; 1312 *ap->a_ncookies = 0; 1313 ap->a_ncookies = NULL; 1314 } 1315 1316 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1317 if (devfs_populate_vp(ap->a_vp) != 0) { 1318 if (tmp_ncookies != NULL) 1319 ap->a_ncookies = tmp_ncookies; 1320 return (EIO); 1321 } 1322 error = 0; 1323 de = ap->a_vp->v_data; 1324 off = 0; 1325 TAILQ_FOREACH(dd, &de->de_dlist, de_list) { 1326 KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__)); 1327 if (dd->de_flags & (DE_COVERED | DE_WHITEOUT)) 1328 continue; 1329 if (devfs_prison_check(dd, uio->uio_td)) 1330 continue; 1331 if (dd->de_dirent->d_type == DT_DIR) 1332 de = dd->de_dir; 1333 else 1334 de = dd; 1335 dp = dd->de_dirent; 1336 MPASS(dp->d_reclen == GENERIC_DIRSIZ(dp)); 1337 if (dp->d_reclen > uio->uio_resid) 1338 break; 1339 dp->d_fileno = de->de_inode; 1340 if (off >= uio->uio_offset) { 1341 error = vfs_read_dirent(ap, dp, off); 1342 if (error) 1343 break; 1344 } 1345 off += dp->d_reclen; 1346 } 1347 sx_xunlock(&dmp->dm_lock); 1348 uio->uio_offset = off; 1349 1350 /* 1351 * Restore ap->a_ncookies if it wasn't originally NULL in the first 1352 * place. 1353 */ 1354 if (tmp_ncookies != NULL) 1355 ap->a_ncookies = tmp_ncookies; 1356 1357 return (error); 1358 } 1359 1360 static int 1361 devfs_readlink(struct vop_readlink_args *ap) 1362 { 1363 struct devfs_dirent *de; 1364 1365 de = ap->a_vp->v_data; 1366 return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio)); 1367 } 1368 1369 static int 1370 devfs_reclaim(struct vop_reclaim_args *ap) 1371 { 1372 struct vnode *vp; 1373 struct devfs_dirent *de; 1374 1375 vp = ap->a_vp; 1376 mtx_lock(&devfs_de_interlock); 1377 de = vp->v_data; 1378 if (de != NULL) { 1379 de->de_vnode = NULL; 1380 vp->v_data = NULL; 1381 } 1382 mtx_unlock(&devfs_de_interlock); 1383 vnode_destroy_vobject(vp); 1384 return (0); 1385 } 1386 1387 static int 1388 devfs_reclaim_vchr(struct vop_reclaim_args *ap) 1389 { 1390 struct vnode *vp; 1391 struct cdev *dev; 1392 1393 vp = ap->a_vp; 1394 MPASS(vp->v_type == VCHR); 1395 1396 devfs_reclaim(ap); 1397 1398 VI_LOCK(vp); 1399 dev_lock(); 1400 dev = vp->v_rdev; 1401 vp->v_rdev = NULL; 1402 if (dev != NULL) 1403 dev->si_usecount -= vp->v_usecount; 1404 dev_unlock(); 1405 VI_UNLOCK(vp); 1406 if (dev != NULL) 1407 dev_rel(dev); 1408 return (0); 1409 } 1410 1411 static int 1412 devfs_remove(struct vop_remove_args *ap) 1413 { 1414 struct vnode *dvp = ap->a_dvp; 1415 struct vnode *vp = ap->a_vp; 1416 struct devfs_dirent *dd; 1417 struct devfs_dirent *de, *de_covered; 1418 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); 1419 1420 ASSERT_VOP_ELOCKED(dvp, "devfs_remove"); 1421 ASSERT_VOP_ELOCKED(vp, "devfs_remove"); 1422 1423 sx_xlock(&dmp->dm_lock); 1424 dd = ap->a_dvp->v_data; 1425 de = vp->v_data; 1426 if (de->de_cdp == NULL) { 1427 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 1428 if (de->de_dirent->d_type == DT_LNK) { 1429 de_covered = devfs_find(dd, de->de_dirent->d_name, 1430 de->de_dirent->d_namlen, 0); 1431 if (de_covered != NULL) 1432 de_covered->de_flags &= ~DE_COVERED; 1433 } 1434 /* We need to unlock dvp because devfs_delete() may lock it. */ 1435 VOP_UNLOCK(vp, 0); 1436 if (dvp != vp) 1437 VOP_UNLOCK(dvp, 0); 1438 devfs_delete(dmp, de, 0); 1439 sx_xunlock(&dmp->dm_lock); 1440 if (dvp != vp) 1441 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1442 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1443 } else { 1444 de->de_flags |= DE_WHITEOUT; 1445 sx_xunlock(&dmp->dm_lock); 1446 } 1447 return (0); 1448 } 1449 1450 /* 1451 * Revoke is called on a tty when a terminal session ends. The vnode 1452 * is orphaned by setting v_op to deadfs so we need to let go of it 1453 * as well so that we create a new one next time around. 1454 * 1455 */ 1456 static int 1457 devfs_revoke(struct vop_revoke_args *ap) 1458 { 1459 struct vnode *vp = ap->a_vp, *vp2; 1460 struct cdev *dev; 1461 struct cdev_priv *cdp; 1462 struct devfs_dirent *de; 1463 u_int i; 1464 1465 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL")); 1466 1467 dev = vp->v_rdev; 1468 cdp = cdev2priv(dev); 1469 1470 dev_lock(); 1471 cdp->cdp_inuse++; 1472 dev_unlock(); 1473 1474 vhold(vp); 1475 vgone(vp); 1476 vdrop(vp); 1477 1478 VOP_UNLOCK(vp,0); 1479 loop: 1480 for (;;) { 1481 mtx_lock(&devfs_de_interlock); 1482 dev_lock(); 1483 vp2 = NULL; 1484 for (i = 0; i <= cdp->cdp_maxdirent; i++) { 1485 de = cdp->cdp_dirents[i]; 1486 if (de == NULL) 1487 continue; 1488 1489 vp2 = de->de_vnode; 1490 if (vp2 != NULL) { 1491 dev_unlock(); 1492 VI_LOCK(vp2); 1493 mtx_unlock(&devfs_de_interlock); 1494 if (vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK, 1495 curthread)) 1496 goto loop; 1497 vhold(vp2); 1498 vgone(vp2); 1499 vdrop(vp2); 1500 vput(vp2); 1501 break; 1502 } 1503 } 1504 if (vp2 != NULL) { 1505 continue; 1506 } 1507 dev_unlock(); 1508 mtx_unlock(&devfs_de_interlock); 1509 break; 1510 } 1511 dev_lock(); 1512 cdp->cdp_inuse--; 1513 if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) { 1514 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); 1515 dev_unlock(); 1516 dev_rel(&cdp->cdp_c); 1517 } else 1518 dev_unlock(); 1519 1520 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1521 return (0); 1522 } 1523 1524 static int 1525 devfs_rioctl(struct vop_ioctl_args *ap) 1526 { 1527 struct vnode *vp; 1528 struct devfs_mount *dmp; 1529 int error; 1530 1531 vp = ap->a_vp; 1532 vn_lock(vp, LK_SHARED | LK_RETRY); 1533 if (vp->v_iflag & VI_DOOMED) { 1534 VOP_UNLOCK(vp, 0); 1535 return (EBADF); 1536 } 1537 dmp = VFSTODEVFS(vp->v_mount); 1538 sx_xlock(&dmp->dm_lock); 1539 VOP_UNLOCK(vp, 0); 1540 DEVFS_DMP_HOLD(dmp); 1541 devfs_populate(dmp); 1542 if (DEVFS_DMP_DROP(dmp)) { 1543 sx_xunlock(&dmp->dm_lock); 1544 devfs_unmount_final(dmp); 1545 return (ENOENT); 1546 } 1547 error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td); 1548 sx_xunlock(&dmp->dm_lock); 1549 return (error); 1550 } 1551 1552 static int 1553 devfs_rread(struct vop_read_args *ap) 1554 { 1555 1556 if (ap->a_vp->v_type != VDIR) 1557 return (EINVAL); 1558 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL)); 1559 } 1560 1561 static int 1562 devfs_setattr(struct vop_setattr_args *ap) 1563 { 1564 struct devfs_dirent *de; 1565 struct vattr *vap; 1566 struct vnode *vp; 1567 struct thread *td; 1568 int c, error; 1569 uid_t uid; 1570 gid_t gid; 1571 1572 vap = ap->a_vap; 1573 vp = ap->a_vp; 1574 td = curthread; 1575 if ((vap->va_type != VNON) || 1576 (vap->va_nlink != VNOVAL) || 1577 (vap->va_fsid != VNOVAL) || 1578 (vap->va_fileid != VNOVAL) || 1579 (vap->va_blocksize != VNOVAL) || 1580 (vap->va_flags != VNOVAL && vap->va_flags != 0) || 1581 (vap->va_rdev != VNOVAL) || 1582 ((int)vap->va_bytes != VNOVAL) || 1583 (vap->va_gen != VNOVAL)) { 1584 return (EINVAL); 1585 } 1586 1587 error = devfs_populate_vp(vp); 1588 if (error != 0) 1589 return (error); 1590 1591 de = vp->v_data; 1592 if (vp->v_type == VDIR) 1593 de = de->de_dir; 1594 1595 c = 0; 1596 if (vap->va_uid == (uid_t)VNOVAL) 1597 uid = de->de_uid; 1598 else 1599 uid = vap->va_uid; 1600 if (vap->va_gid == (gid_t)VNOVAL) 1601 gid = de->de_gid; 1602 else 1603 gid = vap->va_gid; 1604 if (uid != de->de_uid || gid != de->de_gid) { 1605 if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid || 1606 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) { 1607 error = priv_check(td, PRIV_VFS_CHOWN); 1608 if (error != 0) 1609 goto ret; 1610 } 1611 de->de_uid = uid; 1612 de->de_gid = gid; 1613 c = 1; 1614 } 1615 1616 if (vap->va_mode != (mode_t)VNOVAL) { 1617 if (ap->a_cred->cr_uid != de->de_uid) { 1618 error = priv_check(td, PRIV_VFS_ADMIN); 1619 if (error != 0) 1620 goto ret; 1621 } 1622 de->de_mode = vap->va_mode; 1623 c = 1; 1624 } 1625 1626 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 1627 error = vn_utimes_perm(vp, vap, ap->a_cred, td); 1628 if (error != 0) 1629 goto ret; 1630 if (vap->va_atime.tv_sec != VNOVAL) { 1631 if (vp->v_type == VCHR) 1632 vp->v_rdev->si_atime = vap->va_atime; 1633 else 1634 de->de_atime = vap->va_atime; 1635 } 1636 if (vap->va_mtime.tv_sec != VNOVAL) { 1637 if (vp->v_type == VCHR) 1638 vp->v_rdev->si_mtime = vap->va_mtime; 1639 else 1640 de->de_mtime = vap->va_mtime; 1641 } 1642 c = 1; 1643 } 1644 1645 if (c) { 1646 if (vp->v_type == VCHR) 1647 vfs_timestamp(&vp->v_rdev->si_ctime); 1648 else 1649 vfs_timestamp(&de->de_mtime); 1650 } 1651 1652 ret: 1653 sx_xunlock(&VFSTODEVFS(vp->v_mount)->dm_lock); 1654 return (error); 1655 } 1656 1657 #ifdef MAC 1658 static int 1659 devfs_setlabel(struct vop_setlabel_args *ap) 1660 { 1661 struct vnode *vp; 1662 struct devfs_dirent *de; 1663 1664 vp = ap->a_vp; 1665 de = vp->v_data; 1666 1667 mac_vnode_relabel(ap->a_cred, vp, ap->a_label); 1668 mac_devfs_update(vp->v_mount, de, vp); 1669 1670 return (0); 1671 } 1672 #endif 1673 1674 static int 1675 devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td) 1676 { 1677 1678 return (vnops.fo_stat(fp, sb, cred, td)); 1679 } 1680 1681 static int 1682 devfs_symlink(struct vop_symlink_args *ap) 1683 { 1684 int i, error; 1685 struct devfs_dirent *dd; 1686 struct devfs_dirent *de, *de_covered, *de_dotdot; 1687 struct devfs_mount *dmp; 1688 1689 error = priv_check(curthread, PRIV_DEVFS_SYMLINK); 1690 if (error) 1691 return(error); 1692 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1693 if (devfs_populate_vp(ap->a_dvp) != 0) 1694 return (ENOENT); 1695 1696 dd = ap->a_dvp->v_data; 1697 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen); 1698 de->de_flags = DE_USER; 1699 de->de_uid = 0; 1700 de->de_gid = 0; 1701 de->de_mode = 0755; 1702 de->de_inode = alloc_unr(devfs_inos); 1703 de->de_dir = dd; 1704 de->de_dirent->d_type = DT_LNK; 1705 i = strlen(ap->a_target) + 1; 1706 de->de_symlink = malloc(i, M_DEVFS, M_WAITOK); 1707 bcopy(ap->a_target, de->de_symlink, i); 1708 #ifdef MAC 1709 mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de); 1710 #endif 1711 de_covered = devfs_find(dd, de->de_dirent->d_name, 1712 de->de_dirent->d_namlen, 0); 1713 if (de_covered != NULL) { 1714 if ((de_covered->de_flags & DE_USER) != 0) { 1715 devfs_delete(dmp, de, DEVFS_DEL_NORECURSE); 1716 sx_xunlock(&dmp->dm_lock); 1717 return (EEXIST); 1718 } 1719 KASSERT((de_covered->de_flags & DE_COVERED) == 0, 1720 ("devfs_symlink: entry %p already covered", de_covered)); 1721 de_covered->de_flags |= DE_COVERED; 1722 } 1723 1724 de_dotdot = TAILQ_FIRST(&dd->de_dlist); /* "." */ 1725 de_dotdot = TAILQ_NEXT(de_dotdot, de_list); /* ".." */ 1726 TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list); 1727 devfs_dir_ref_de(dmp, dd); 1728 devfs_rules_apply(dmp, de); 1729 1730 return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp)); 1731 } 1732 1733 static int 1734 devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td) 1735 { 1736 1737 return (vnops.fo_truncate(fp, length, cred, td)); 1738 } 1739 1740 static int 1741 devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred, 1742 int flags, struct thread *td) 1743 { 1744 struct cdev *dev; 1745 int error, ioflag, ref; 1746 ssize_t resid; 1747 struct cdevsw *dsw; 1748 struct file *fpop; 1749 1750 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1751 return (EINVAL); 1752 fpop = td->td_fpop; 1753 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1754 if (error != 0) { 1755 error = vnops.fo_write(fp, uio, cred, flags, td); 1756 return (error); 1757 } 1758 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td)); 1759 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC); 1760 if (ioflag & O_DIRECT) 1761 ioflag |= IO_DIRECT; 1762 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1763 1764 resid = uio->uio_resid; 1765 1766 error = dsw->d_write(dev, uio, ioflag); 1767 if (uio->uio_resid != resid || (error == 0 && resid != 0)) { 1768 devfs_timestamp(&dev->si_ctime); 1769 dev->si_mtime = dev->si_ctime; 1770 } 1771 td->td_fpop = fpop; 1772 dev_relthread(dev, ref); 1773 1774 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1775 return (error); 1776 } 1777 1778 static int 1779 devfs_mmap_f(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size, 1780 vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff, 1781 struct thread *td) 1782 { 1783 struct cdev *dev; 1784 struct cdevsw *dsw; 1785 struct mount *mp; 1786 struct vnode *vp; 1787 struct file *fpop; 1788 vm_object_t object; 1789 vm_prot_t maxprot; 1790 int error, ref; 1791 1792 vp = fp->f_vnode; 1793 1794 /* 1795 * Ensure that file and memory protections are 1796 * compatible. 1797 */ 1798 mp = vp->v_mount; 1799 if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) { 1800 maxprot = VM_PROT_NONE; 1801 if ((prot & VM_PROT_EXECUTE) != 0) 1802 return (EACCES); 1803 } else 1804 maxprot = VM_PROT_EXECUTE; 1805 if ((fp->f_flag & FREAD) != 0) 1806 maxprot |= VM_PROT_READ; 1807 else if ((prot & VM_PROT_READ) != 0) 1808 return (EACCES); 1809 1810 /* 1811 * If we are sharing potential changes via MAP_SHARED and we 1812 * are trying to get write permission although we opened it 1813 * without asking for it, bail out. 1814 * 1815 * Note that most character devices always share mappings. 1816 * The one exception is that D_MMAP_ANON devices 1817 * (i.e. /dev/zero) permit private writable mappings. 1818 * 1819 * Rely on vm_mmap_cdev() to fail invalid MAP_PRIVATE requests 1820 * as well as updating maxprot to permit writing for 1821 * D_MMAP_ANON devices rather than doing that here. 1822 */ 1823 if ((flags & MAP_SHARED) != 0) { 1824 if ((fp->f_flag & FWRITE) != 0) 1825 maxprot |= VM_PROT_WRITE; 1826 else if ((prot & VM_PROT_WRITE) != 0) 1827 return (EACCES); 1828 } 1829 maxprot &= cap_maxprot; 1830 1831 fpop = td->td_fpop; 1832 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1833 if (error != 0) 1834 return (error); 1835 1836 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, dev, dsw, &foff, 1837 &object); 1838 td->td_fpop = fpop; 1839 dev_relthread(dev, ref); 1840 if (error != 0) 1841 return (error); 1842 1843 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1844 foff, FALSE, td); 1845 if (error != 0) 1846 vm_object_deallocate(object); 1847 return (error); 1848 } 1849 1850 dev_t 1851 dev2udev(struct cdev *x) 1852 { 1853 if (x == NULL) 1854 return (NODEV); 1855 return (cdev2priv(x)->cdp_inode); 1856 } 1857 1858 static struct fileops devfs_ops_f = { 1859 .fo_read = devfs_read_f, 1860 .fo_write = devfs_write_f, 1861 .fo_truncate = devfs_truncate_f, 1862 .fo_ioctl = devfs_ioctl_f, 1863 .fo_poll = devfs_poll_f, 1864 .fo_kqfilter = devfs_kqfilter_f, 1865 .fo_stat = devfs_stat_f, 1866 .fo_close = devfs_close_f, 1867 .fo_chmod = vn_chmod, 1868 .fo_chown = vn_chown, 1869 .fo_sendfile = vn_sendfile, 1870 .fo_seek = vn_seek, 1871 .fo_fill_kinfo = vn_fill_kinfo, 1872 .fo_mmap = devfs_mmap_f, 1873 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE 1874 }; 1875 1876 /* Vops for non-CHR vnodes in /dev. */ 1877 static struct vop_vector devfs_vnodeops = { 1878 .vop_default = &default_vnodeops, 1879 1880 .vop_access = devfs_access, 1881 .vop_getattr = devfs_getattr, 1882 .vop_ioctl = devfs_rioctl, 1883 .vop_lookup = devfs_lookup, 1884 .vop_mknod = devfs_mknod, 1885 .vop_pathconf = devfs_pathconf, 1886 .vop_read = devfs_rread, 1887 .vop_readdir = devfs_readdir, 1888 .vop_readlink = devfs_readlink, 1889 .vop_reclaim = devfs_reclaim, 1890 .vop_remove = devfs_remove, 1891 .vop_revoke = devfs_revoke, 1892 .vop_setattr = devfs_setattr, 1893 #ifdef MAC 1894 .vop_setlabel = devfs_setlabel, 1895 #endif 1896 .vop_symlink = devfs_symlink, 1897 .vop_vptocnp = devfs_vptocnp, 1898 }; 1899 1900 /* Vops for VCHR vnodes in /dev. */ 1901 static struct vop_vector devfs_specops = { 1902 .vop_default = &default_vnodeops, 1903 1904 .vop_access = devfs_access, 1905 .vop_bmap = VOP_PANIC, 1906 .vop_close = devfs_close, 1907 .vop_create = VOP_PANIC, 1908 .vop_fsync = vop_stdfsync, 1909 .vop_getattr = devfs_getattr, 1910 .vop_ioctl = devfs_ioctl, 1911 .vop_link = VOP_PANIC, 1912 .vop_mkdir = VOP_PANIC, 1913 .vop_mknod = VOP_PANIC, 1914 .vop_open = devfs_open, 1915 .vop_pathconf = devfs_pathconf, 1916 .vop_poll = dead_poll, 1917 .vop_print = devfs_print, 1918 .vop_read = dead_read, 1919 .vop_readdir = VOP_PANIC, 1920 .vop_readlink = VOP_PANIC, 1921 .vop_reallocblks = VOP_PANIC, 1922 .vop_reclaim = devfs_reclaim_vchr, 1923 .vop_remove = devfs_remove, 1924 .vop_rename = VOP_PANIC, 1925 .vop_revoke = devfs_revoke, 1926 .vop_rmdir = VOP_PANIC, 1927 .vop_setattr = devfs_setattr, 1928 #ifdef MAC 1929 .vop_setlabel = devfs_setlabel, 1930 #endif 1931 .vop_strategy = VOP_PANIC, 1932 .vop_symlink = VOP_PANIC, 1933 .vop_vptocnp = devfs_vptocnp, 1934 .vop_write = dead_write, 1935 }; 1936 1937 /* 1938 * Our calling convention to the device drivers used to be that we passed 1939 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_ 1940 * flags instead since that's what open(), close() and ioctl() takes and 1941 * we don't really want vnode.h in device drivers. 1942 * We solved the source compatibility by redefining some vnode flags to 1943 * be the same as the fcntl ones and by sending down the bitwise OR of 1944 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody 1945 * pulls the rug out under this. 1946 */ 1947 CTASSERT(O_NONBLOCK == IO_NDELAY); 1948 CTASSERT(O_FSYNC == IO_SYNC); 1949