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