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