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