devfs_vnops.c revision 281255
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: stable/10/sys/fs/devfs/devfs_vnops.c 281255 2015-04-08 02:15:13Z kib $ 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 66static struct vop_vector devfs_vnodeops; 67static 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 74static MALLOC_DEFINE(M_CDEVPDATA, "DEVFSP", "Metainfo for cdev-fp data"); 75 76struct mtx devfs_de_interlock; 77MTX_SYSINIT(devfs_de_interlock, &devfs_de_interlock, "devfs interlock", MTX_DEF); 78struct sx clone_drain_lock; 79SX_SYSINIT(clone_drain_lock, &clone_drain_lock, "clone events drain lock"); 80struct mtx cdevpriv_mtx; 81MTX_SYSINIT(cdevpriv_mtx, &cdevpriv_mtx, "cdevpriv lock", MTX_DEF); 82 83SYSCTL_DECL(_vfs_devfs); 84 85static int devfs_dotimes; 86SYSCTL_INT(_vfs_devfs, OID_AUTO, dotimes, CTLFLAG_RW, 87 &devfs_dotimes, 0, "Update timestamps on DEVFS with default precision"); 88 89/* 90 * Update devfs node timestamp. Note that updates are unlocked and 91 * stat(2) could see partially updated times. 92 */ 93static void 94devfs_timestamp(struct timespec *tsp) 95{ 96 time_t ts; 97 98 if (devfs_dotimes) { 99 vfs_timestamp(tsp); 100 } else { 101 ts = time_second; 102 if (tsp->tv_sec != ts) { 103 tsp->tv_sec = ts; 104 tsp->tv_nsec = 0; 105 } 106 } 107} 108 109static int 110devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp, 111 int *ref) 112{ 113 114 *dswp = devvn_refthread(fp->f_vnode, devp, ref); 115 if (*devp != fp->f_data) { 116 if (*dswp != NULL) 117 dev_relthread(*devp, *ref); 118 return (ENXIO); 119 } 120 KASSERT((*devp)->si_refcount > 0, 121 ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp))); 122 if (*dswp == NULL) 123 return (ENXIO); 124 curthread->td_fpop = fp; 125 return (0); 126} 127 128int 129devfs_get_cdevpriv(void **datap) 130{ 131 struct file *fp; 132 struct cdev_privdata *p; 133 int error; 134 135 fp = curthread->td_fpop; 136 if (fp == NULL) 137 return (EBADF); 138 p = fp->f_cdevpriv; 139 if (p != NULL) { 140 error = 0; 141 *datap = p->cdpd_data; 142 } else 143 error = ENOENT; 144 return (error); 145} 146 147int 148devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t priv_dtr) 149{ 150 struct file *fp; 151 struct cdev_priv *cdp; 152 struct cdev_privdata *p; 153 int error; 154 155 fp = curthread->td_fpop; 156 if (fp == NULL) 157 return (ENOENT); 158 cdp = cdev2priv((struct cdev *)fp->f_data); 159 p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK); 160 p->cdpd_data = priv; 161 p->cdpd_dtr = priv_dtr; 162 p->cdpd_fp = fp; 163 mtx_lock(&cdevpriv_mtx); 164 if (fp->f_cdevpriv == NULL) { 165 LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list); 166 fp->f_cdevpriv = p; 167 mtx_unlock(&cdevpriv_mtx); 168 error = 0; 169 } else { 170 mtx_unlock(&cdevpriv_mtx); 171 free(p, M_CDEVPDATA); 172 error = EBUSY; 173 } 174 return (error); 175} 176 177void 178devfs_destroy_cdevpriv(struct cdev_privdata *p) 179{ 180 181 mtx_assert(&cdevpriv_mtx, MA_OWNED); 182 p->cdpd_fp->f_cdevpriv = NULL; 183 LIST_REMOVE(p, cdpd_list); 184 mtx_unlock(&cdevpriv_mtx); 185 (p->cdpd_dtr)(p->cdpd_data); 186 free(p, M_CDEVPDATA); 187} 188 189void 190devfs_fpdrop(struct file *fp) 191{ 192 struct cdev_privdata *p; 193 194 mtx_lock(&cdevpriv_mtx); 195 if ((p = fp->f_cdevpriv) == NULL) { 196 mtx_unlock(&cdevpriv_mtx); 197 return; 198 } 199 devfs_destroy_cdevpriv(p); 200} 201 202void 203devfs_clear_cdevpriv(void) 204{ 205 struct file *fp; 206 207 fp = curthread->td_fpop; 208 if (fp == NULL) 209 return; 210 devfs_fpdrop(fp); 211} 212 213/* 214 * On success devfs_populate_vp() returns with dmp->dm_lock held. 215 */ 216static int 217devfs_populate_vp(struct vnode *vp) 218{ 219 struct devfs_dirent *de; 220 struct devfs_mount *dmp; 221 int locked; 222 223 ASSERT_VOP_LOCKED(vp, "devfs_populate_vp"); 224 225 dmp = VFSTODEVFS(vp->v_mount); 226 locked = VOP_ISLOCKED(vp); 227 228 sx_xlock(&dmp->dm_lock); 229 DEVFS_DMP_HOLD(dmp); 230 231 /* Can't call devfs_populate() with the vnode lock held. */ 232 VOP_UNLOCK(vp, 0); 233 devfs_populate(dmp); 234 235 sx_xunlock(&dmp->dm_lock); 236 vn_lock(vp, locked | LK_RETRY); 237 sx_xlock(&dmp->dm_lock); 238 if (DEVFS_DMP_DROP(dmp)) { 239 sx_xunlock(&dmp->dm_lock); 240 devfs_unmount_final(dmp); 241 return (EBADF); 242 } 243 if ((vp->v_iflag & VI_DOOMED) != 0) { 244 sx_xunlock(&dmp->dm_lock); 245 return (EBADF); 246 } 247 de = vp->v_data; 248 KASSERT(de != NULL, 249 ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed")); 250 if ((de->de_flags & DE_DOOMED) != 0) { 251 sx_xunlock(&dmp->dm_lock); 252 return (EBADF); 253 } 254 255 return (0); 256} 257 258static int 259devfs_vptocnp(struct vop_vptocnp_args *ap) 260{ 261 struct vnode *vp = ap->a_vp; 262 struct vnode **dvp = ap->a_vpp; 263 struct devfs_mount *dmp; 264 char *buf = ap->a_buf; 265 int *buflen = ap->a_buflen; 266 struct devfs_dirent *dd, *de; 267 int i, error; 268 269 dmp = VFSTODEVFS(vp->v_mount); 270 271 error = devfs_populate_vp(vp); 272 if (error != 0) 273 return (error); 274 275 i = *buflen; 276 dd = vp->v_data; 277 278 if (vp->v_type == VCHR) { 279 i -= strlen(dd->de_cdp->cdp_c.si_name); 280 if (i < 0) { 281 error = ENOMEM; 282 goto finished; 283 } 284 bcopy(dd->de_cdp->cdp_c.si_name, buf + i, 285 strlen(dd->de_cdp->cdp_c.si_name)); 286 de = dd->de_dir; 287 } else if (vp->v_type == VDIR) { 288 if (dd == dmp->dm_rootdir) { 289 *dvp = vp; 290 vref(*dvp); 291 goto finished; 292 } 293 i -= dd->de_dirent->d_namlen; 294 if (i < 0) { 295 error = ENOMEM; 296 goto finished; 297 } 298 bcopy(dd->de_dirent->d_name, buf + i, 299 dd->de_dirent->d_namlen); 300 de = dd; 301 } else { 302 error = ENOENT; 303 goto finished; 304 } 305 *buflen = i; 306 de = devfs_parent_dirent(de); 307 if (de == NULL) { 308 error = ENOENT; 309 goto finished; 310 } 311 mtx_lock(&devfs_de_interlock); 312 *dvp = de->de_vnode; 313 if (*dvp != NULL) { 314 VI_LOCK(*dvp); 315 mtx_unlock(&devfs_de_interlock); 316 vholdl(*dvp); 317 VI_UNLOCK(*dvp); 318 vref(*dvp); 319 vdrop(*dvp); 320 } else { 321 mtx_unlock(&devfs_de_interlock); 322 error = ENOENT; 323 } 324finished: 325 sx_xunlock(&dmp->dm_lock); 326 return (error); 327} 328 329/* 330 * Construct the fully qualified path name relative to the mountpoint. 331 * If a NULL cnp is provided, no '/' is appended to the resulting path. 332 */ 333char * 334devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd, 335 struct componentname *cnp) 336{ 337 int i; 338 struct devfs_dirent *de; 339 340 sx_assert(&dmp->dm_lock, SA_LOCKED); 341 342 i = SPECNAMELEN; 343 buf[i] = '\0'; 344 if (cnp != NULL) 345 i -= cnp->cn_namelen; 346 if (i < 0) 347 return (NULL); 348 if (cnp != NULL) 349 bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen); 350 de = dd; 351 while (de != dmp->dm_rootdir) { 352 if (cnp != NULL || i < SPECNAMELEN) { 353 i--; 354 if (i < 0) 355 return (NULL); 356 buf[i] = '/'; 357 } 358 i -= de->de_dirent->d_namlen; 359 if (i < 0) 360 return (NULL); 361 bcopy(de->de_dirent->d_name, buf + i, 362 de->de_dirent->d_namlen); 363 de = devfs_parent_dirent(de); 364 if (de == NULL) 365 return (NULL); 366 } 367 return (buf + i); 368} 369 370static int 371devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp, 372 struct devfs_dirent *de) 373{ 374 int not_found; 375 376 not_found = 0; 377 if (de->de_flags & DE_DOOMED) 378 not_found = 1; 379 if (DEVFS_DE_DROP(de)) { 380 KASSERT(not_found == 1, ("DEVFS de dropped but not doomed")); 381 devfs_dirent_free(de); 382 } 383 if (DEVFS_DMP_DROP(dmp)) { 384 KASSERT(not_found == 1, 385 ("DEVFS mount struct freed before dirent")); 386 not_found = 2; 387 sx_xunlock(&dmp->dm_lock); 388 devfs_unmount_final(dmp); 389 } 390 if (not_found == 1 || (drop_dm_lock && not_found != 2)) 391 sx_unlock(&dmp->dm_lock); 392 return (not_found); 393} 394 395static void 396devfs_insmntque_dtr(struct vnode *vp, void *arg) 397{ 398 struct devfs_dirent *de; 399 400 de = (struct devfs_dirent *)arg; 401 mtx_lock(&devfs_de_interlock); 402 vp->v_data = NULL; 403 de->de_vnode = NULL; 404 mtx_unlock(&devfs_de_interlock); 405 vgone(vp); 406 vput(vp); 407} 408 409/* 410 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops 411 * it on return. 412 */ 413int 414devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode, 415 struct vnode **vpp) 416{ 417 int error; 418 struct vnode *vp; 419 struct cdev *dev; 420 struct devfs_mount *dmp; 421 struct cdevsw *dsw; 422 423 dmp = VFSTODEVFS(mp); 424 if (de->de_flags & DE_DOOMED) { 425 sx_xunlock(&dmp->dm_lock); 426 return (ENOENT); 427 } 428loop: 429 DEVFS_DE_HOLD(de); 430 DEVFS_DMP_HOLD(dmp); 431 mtx_lock(&devfs_de_interlock); 432 vp = de->de_vnode; 433 if (vp != NULL) { 434 VI_LOCK(vp); 435 mtx_unlock(&devfs_de_interlock); 436 sx_xunlock(&dmp->dm_lock); 437 vget(vp, lockmode | LK_INTERLOCK | LK_RETRY, curthread); 438 sx_xlock(&dmp->dm_lock); 439 if (devfs_allocv_drop_refs(0, dmp, de)) { 440 vput(vp); 441 return (ENOENT); 442 } 443 else if ((vp->v_iflag & VI_DOOMED) != 0) { 444 mtx_lock(&devfs_de_interlock); 445 if (de->de_vnode == vp) { 446 de->de_vnode = NULL; 447 vp->v_data = NULL; 448 } 449 mtx_unlock(&devfs_de_interlock); 450 vput(vp); 451 goto loop; 452 } 453 sx_xunlock(&dmp->dm_lock); 454 *vpp = vp; 455 return (0); 456 } 457 mtx_unlock(&devfs_de_interlock); 458 if (de->de_dirent->d_type == DT_CHR) { 459 if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) { 460 devfs_allocv_drop_refs(1, dmp, de); 461 return (ENOENT); 462 } 463 dev = &de->de_cdp->cdp_c; 464 } else { 465 dev = NULL; 466 } 467 error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp); 468 if (error != 0) { 469 devfs_allocv_drop_refs(1, dmp, de); 470 printf("devfs_allocv: failed to allocate new vnode\n"); 471 return (error); 472 } 473 474 if (de->de_dirent->d_type == DT_CHR) { 475 vp->v_type = VCHR; 476 VI_LOCK(vp); 477 dev_lock(); 478 dev_refl(dev); 479 /* XXX: v_rdev should be protect by vnode lock */ 480 vp->v_rdev = dev; 481 KASSERT(vp->v_usecount == 1, 482 ("%s %d (%d)\n", __func__, __LINE__, vp->v_usecount)); 483 dev->si_usecount += vp->v_usecount; 484 /* Special casing of ttys for deadfs. Probably redundant. */ 485 dsw = dev->si_devsw; 486 if (dsw != NULL && (dsw->d_flags & D_TTY) != 0) 487 vp->v_vflag |= VV_ISTTY; 488 dev_unlock(); 489 VI_UNLOCK(vp); 490 if ((dev->si_flags & SI_ETERNAL) != 0) 491 vp->v_vflag |= VV_ETERNALDEV; 492 vp->v_op = &devfs_specops; 493 } else if (de->de_dirent->d_type == DT_DIR) { 494 vp->v_type = VDIR; 495 } else if (de->de_dirent->d_type == DT_LNK) { 496 vp->v_type = VLNK; 497 } else { 498 vp->v_type = VBAD; 499 } 500 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS); 501 VN_LOCK_ASHARE(vp); 502 mtx_lock(&devfs_de_interlock); 503 vp->v_data = de; 504 de->de_vnode = vp; 505 mtx_unlock(&devfs_de_interlock); 506 error = insmntque1(vp, mp, devfs_insmntque_dtr, de); 507 if (error != 0) { 508 (void) devfs_allocv_drop_refs(1, dmp, de); 509 return (error); 510 } 511 if (devfs_allocv_drop_refs(0, dmp, de)) { 512 vput(vp); 513 return (ENOENT); 514 } 515#ifdef MAC 516 mac_devfs_vnode_associate(mp, de, vp); 517#endif 518 sx_xunlock(&dmp->dm_lock); 519 *vpp = vp; 520 return (0); 521} 522 523static int 524devfs_access(struct vop_access_args *ap) 525{ 526 struct vnode *vp = ap->a_vp; 527 struct devfs_dirent *de; 528 int error; 529 530 de = vp->v_data; 531 if (vp->v_type == VDIR) 532 de = de->de_dir; 533 534 error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid, 535 ap->a_accmode, ap->a_cred, NULL); 536 if (error == 0) 537 return (0); 538 if (error != EACCES) 539 return (error); 540 /* We do, however, allow access to the controlling terminal */ 541 if (!(ap->a_td->td_proc->p_flag & P_CONTROLT)) 542 return (error); 543 if (ap->a_td->td_proc->p_session->s_ttydp == de->de_cdp) 544 return (0); 545 return (error); 546} 547 548/* ARGSUSED */ 549static int 550devfs_close(struct vop_close_args *ap) 551{ 552 struct vnode *vp = ap->a_vp, *oldvp; 553 struct thread *td = ap->a_td; 554 struct cdev *dev = vp->v_rdev; 555 struct cdevsw *dsw; 556 int vp_locked, error, ref; 557 558 /* 559 * XXX: Don't call d_close() if we were called because of 560 * XXX: insmntque1() failure. 561 */ 562 if (vp->v_data == NULL) 563 return (0); 564 565 /* 566 * Hack: a tty device that is a controlling terminal 567 * has a reference from the session structure. 568 * We cannot easily tell that a character device is 569 * a controlling terminal, unless it is the closing 570 * process' controlling terminal. In that case, 571 * if the reference count is 2 (this last descriptor 572 * plus the session), release the reference from the session. 573 */ 574 oldvp = NULL; 575 sx_xlock(&proctree_lock); 576 if (td && vp == td->td_proc->p_session->s_ttyvp) { 577 SESS_LOCK(td->td_proc->p_session); 578 VI_LOCK(vp); 579 if (count_dev(dev) == 2 && (vp->v_iflag & VI_DOOMED) == 0) { 580 td->td_proc->p_session->s_ttyvp = NULL; 581 td->td_proc->p_session->s_ttydp = NULL; 582 oldvp = vp; 583 } 584 VI_UNLOCK(vp); 585 SESS_UNLOCK(td->td_proc->p_session); 586 } 587 sx_xunlock(&proctree_lock); 588 if (oldvp != NULL) 589 vrele(oldvp); 590 /* 591 * We do not want to really close the device if it 592 * is still in use unless we are trying to close it 593 * forcibly. Since every use (buffer, vnode, swap, cmap) 594 * holds a reference to the vnode, and because we mark 595 * any other vnodes that alias this device, when the 596 * sum of the reference counts on all the aliased 597 * vnodes descends to one, we are on last close. 598 */ 599 dsw = dev_refthread(dev, &ref); 600 if (dsw == NULL) 601 return (ENXIO); 602 VI_LOCK(vp); 603 if (vp->v_iflag & VI_DOOMED) { 604 /* Forced close. */ 605 } else if (dsw->d_flags & D_TRACKCLOSE) { 606 /* Keep device updated on status. */ 607 } else if (count_dev(dev) > 1) { 608 VI_UNLOCK(vp); 609 dev_relthread(dev, ref); 610 return (0); 611 } 612 vholdl(vp); 613 VI_UNLOCK(vp); 614 vp_locked = VOP_ISLOCKED(vp); 615 VOP_UNLOCK(vp, 0); 616 KASSERT(dev->si_refcount > 0, 617 ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev))); 618 error = dsw->d_close(dev, ap->a_fflag, S_IFCHR, td); 619 dev_relthread(dev, ref); 620 vn_lock(vp, vp_locked | LK_RETRY); 621 vdrop(vp); 622 return (error); 623} 624 625static int 626devfs_close_f(struct file *fp, struct thread *td) 627{ 628 int error; 629 struct file *fpop; 630 631 /* 632 * NB: td may be NULL if this descriptor is closed due to 633 * garbage collection from a closed UNIX domain socket. 634 */ 635 fpop = curthread->td_fpop; 636 curthread->td_fpop = fp; 637 error = vnops.fo_close(fp, td); 638 curthread->td_fpop = fpop; 639 640 /* 641 * The f_cdevpriv cannot be assigned non-NULL value while we 642 * are destroying the file. 643 */ 644 if (fp->f_cdevpriv != NULL) 645 devfs_fpdrop(fp); 646 return (error); 647} 648 649static int 650devfs_fsync(struct vop_fsync_args *ap) 651{ 652 int error; 653 struct bufobj *bo; 654 struct devfs_dirent *de; 655 656 if (!vn_isdisk(ap->a_vp, &error)) { 657 bo = &ap->a_vp->v_bufobj; 658 de = ap->a_vp->v_data; 659 if (error == ENXIO && bo->bo_dirty.bv_cnt > 0) { 660 printf("Device %s went missing before all of the data " 661 "could be written to it; expect data loss.\n", 662 de->de_dirent->d_name); 663 664 error = vop_stdfsync(ap); 665 if (bo->bo_dirty.bv_cnt != 0 || error != 0) 666 panic("devfs_fsync: vop_stdfsync failed."); 667 } 668 669 return (0); 670 } 671 672 return (vop_stdfsync(ap)); 673} 674 675static int 676devfs_getattr(struct vop_getattr_args *ap) 677{ 678 struct vnode *vp = ap->a_vp; 679 struct vattr *vap = ap->a_vap; 680 int error; 681 struct devfs_dirent *de; 682 struct devfs_mount *dmp; 683 struct cdev *dev; 684 685 error = devfs_populate_vp(vp); 686 if (error != 0) 687 return (error); 688 689 dmp = VFSTODEVFS(vp->v_mount); 690 sx_xunlock(&dmp->dm_lock); 691 692 de = vp->v_data; 693 KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp)); 694 if (vp->v_type == VDIR) { 695 de = de->de_dir; 696 KASSERT(de != NULL, 697 ("Null dir dirent in devfs_getattr vp=%p", vp)); 698 } 699 vap->va_uid = de->de_uid; 700 vap->va_gid = de->de_gid; 701 vap->va_mode = de->de_mode; 702 if (vp->v_type == VLNK) 703 vap->va_size = strlen(de->de_symlink); 704 else if (vp->v_type == VDIR) 705 vap->va_size = vap->va_bytes = DEV_BSIZE; 706 else 707 vap->va_size = 0; 708 if (vp->v_type != VDIR) 709 vap->va_bytes = 0; 710 vap->va_blocksize = DEV_BSIZE; 711 vap->va_type = vp->v_type; 712 713#define fix(aa) \ 714 do { \ 715 if ((aa).tv_sec <= 3600) { \ 716 (aa).tv_sec = boottime.tv_sec; \ 717 (aa).tv_nsec = boottime.tv_usec * 1000; \ 718 } \ 719 } while (0) 720 721 if (vp->v_type != VCHR) { 722 fix(de->de_atime); 723 vap->va_atime = de->de_atime; 724 fix(de->de_mtime); 725 vap->va_mtime = de->de_mtime; 726 fix(de->de_ctime); 727 vap->va_ctime = de->de_ctime; 728 } else { 729 dev = vp->v_rdev; 730 fix(dev->si_atime); 731 vap->va_atime = dev->si_atime; 732 fix(dev->si_mtime); 733 vap->va_mtime = dev->si_mtime; 734 fix(dev->si_ctime); 735 vap->va_ctime = dev->si_ctime; 736 737 vap->va_rdev = cdev2priv(dev)->cdp_inode; 738 } 739 vap->va_gen = 0; 740 vap->va_flags = 0; 741 vap->va_filerev = 0; 742 vap->va_nlink = de->de_links; 743 vap->va_fileid = de->de_inode; 744 745 return (error); 746} 747 748/* ARGSUSED */ 749static int 750devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td) 751{ 752 struct cdev *dev; 753 struct cdevsw *dsw; 754 struct vnode *vp; 755 struct vnode *vpold; 756 int error, i, ref; 757 const char *p; 758 struct fiodgname_arg *fgn; 759 struct file *fpop; 760 761 fpop = td->td_fpop; 762 error = devfs_fp_check(fp, &dev, &dsw, &ref); 763 if (error != 0) { 764 error = vnops.fo_ioctl(fp, com, data, cred, td); 765 return (error); 766 } 767 768 if (com == FIODTYPE) { 769 *(int *)data = dsw->d_flags & D_TYPEMASK; 770 td->td_fpop = fpop; 771 dev_relthread(dev, ref); 772 return (0); 773 } else if (com == FIODGNAME) { 774 fgn = data; 775 p = devtoname(dev); 776 i = strlen(p) + 1; 777 if (i > fgn->len) 778 error = EINVAL; 779 else 780 error = copyout(p, fgn->buf, i); 781 td->td_fpop = fpop; 782 dev_relthread(dev, ref); 783 return (error); 784 } 785 error = dsw->d_ioctl(dev, com, data, fp->f_flag, td); 786 td->td_fpop = NULL; 787 dev_relthread(dev, ref); 788 if (error == ENOIOCTL) 789 error = ENOTTY; 790 if (error == 0 && com == TIOCSCTTY) { 791 vp = fp->f_vnode; 792 793 /* Do nothing if reassigning same control tty */ 794 sx_slock(&proctree_lock); 795 if (td->td_proc->p_session->s_ttyvp == vp) { 796 sx_sunlock(&proctree_lock); 797 return (0); 798 } 799 800 vpold = td->td_proc->p_session->s_ttyvp; 801 VREF(vp); 802 SESS_LOCK(td->td_proc->p_session); 803 td->td_proc->p_session->s_ttyvp = vp; 804 td->td_proc->p_session->s_ttydp = cdev2priv(dev); 805 SESS_UNLOCK(td->td_proc->p_session); 806 807 sx_sunlock(&proctree_lock); 808 809 /* Get rid of reference to old control tty */ 810 if (vpold) 811 vrele(vpold); 812 } 813 return (error); 814} 815 816/* ARGSUSED */ 817static int 818devfs_kqfilter_f(struct file *fp, struct knote *kn) 819{ 820 struct cdev *dev; 821 struct cdevsw *dsw; 822 int error, ref; 823 struct file *fpop; 824 struct thread *td; 825 826 td = curthread; 827 fpop = td->td_fpop; 828 error = devfs_fp_check(fp, &dev, &dsw, &ref); 829 if (error) 830 return (error); 831 error = dsw->d_kqfilter(dev, kn); 832 td->td_fpop = fpop; 833 dev_relthread(dev, ref); 834 return (error); 835} 836 837static inline int 838devfs_prison_check(struct devfs_dirent *de, struct thread *td) 839{ 840 struct cdev_priv *cdp; 841 struct ucred *dcr; 842 int error; 843 844 cdp = de->de_cdp; 845 if (cdp == NULL) 846 return (0); 847 dcr = cdp->cdp_c.si_cred; 848 if (dcr == NULL) 849 return (0); 850 851 error = prison_check(td->td_ucred, dcr); 852 if (error == 0) 853 return (0); 854 /* We do, however, allow access to the controlling terminal */ 855 if (!(td->td_proc->p_flag & P_CONTROLT)) 856 return (error); 857 if (td->td_proc->p_session->s_ttydp == cdp) 858 return (0); 859 return (error); 860} 861 862static int 863devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock) 864{ 865 struct componentname *cnp; 866 struct vnode *dvp, **vpp; 867 struct thread *td; 868 struct devfs_dirent *de, *dd; 869 struct devfs_dirent **dde; 870 struct devfs_mount *dmp; 871 struct cdev *cdev; 872 int error, flags, nameiop, dvplocked; 873 char specname[SPECNAMELEN + 1], *pname; 874 875 cnp = ap->a_cnp; 876 vpp = ap->a_vpp; 877 dvp = ap->a_dvp; 878 pname = cnp->cn_nameptr; 879 td = cnp->cn_thread; 880 flags = cnp->cn_flags; 881 nameiop = cnp->cn_nameiop; 882 dmp = VFSTODEVFS(dvp->v_mount); 883 dd = dvp->v_data; 884 *vpp = NULLVP; 885 886 if ((flags & ISLASTCN) && nameiop == RENAME) 887 return (EOPNOTSUPP); 888 889 if (dvp->v_type != VDIR) 890 return (ENOTDIR); 891 892 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT)) 893 return (EIO); 894 895 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td); 896 if (error) 897 return (error); 898 899 if (cnp->cn_namelen == 1 && *pname == '.') { 900 if ((flags & ISLASTCN) && nameiop != LOOKUP) 901 return (EINVAL); 902 *vpp = dvp; 903 VREF(dvp); 904 return (0); 905 } 906 907 if (flags & ISDOTDOT) { 908 if ((flags & ISLASTCN) && nameiop != LOOKUP) 909 return (EINVAL); 910 de = devfs_parent_dirent(dd); 911 if (de == NULL) 912 return (ENOENT); 913 dvplocked = VOP_ISLOCKED(dvp); 914 VOP_UNLOCK(dvp, 0); 915 error = devfs_allocv(de, dvp->v_mount, 916 cnp->cn_lkflags & LK_TYPE_MASK, vpp); 917 *dm_unlock = 0; 918 vn_lock(dvp, dvplocked | LK_RETRY); 919 return (error); 920 } 921 922 dd = dvp->v_data; 923 de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0); 924 while (de == NULL) { /* While(...) so we can use break */ 925 926 if (nameiop == DELETE) 927 return (ENOENT); 928 929 /* 930 * OK, we didn't have an entry for the name we were asked for 931 * so we try to see if anybody can create it on demand. 932 */ 933 pname = devfs_fqpn(specname, dmp, dd, cnp); 934 if (pname == NULL) 935 break; 936 937 cdev = NULL; 938 DEVFS_DMP_HOLD(dmp); 939 sx_xunlock(&dmp->dm_lock); 940 sx_slock(&clone_drain_lock); 941 EVENTHANDLER_INVOKE(dev_clone, 942 td->td_ucred, pname, strlen(pname), &cdev); 943 sx_sunlock(&clone_drain_lock); 944 945 if (cdev == NULL) 946 sx_xlock(&dmp->dm_lock); 947 else if (devfs_populate_vp(dvp) != 0) { 948 *dm_unlock = 0; 949 sx_xlock(&dmp->dm_lock); 950 if (DEVFS_DMP_DROP(dmp)) { 951 sx_xunlock(&dmp->dm_lock); 952 devfs_unmount_final(dmp); 953 } else 954 sx_xunlock(&dmp->dm_lock); 955 dev_rel(cdev); 956 return (ENOENT); 957 } 958 if (DEVFS_DMP_DROP(dmp)) { 959 *dm_unlock = 0; 960 sx_xunlock(&dmp->dm_lock); 961 devfs_unmount_final(dmp); 962 if (cdev != NULL) 963 dev_rel(cdev); 964 return (ENOENT); 965 } 966 967 if (cdev == NULL) 968 break; 969 970 dev_lock(); 971 dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx]; 972 if (dde != NULL && *dde != NULL) 973 de = *dde; 974 dev_unlock(); 975 dev_rel(cdev); 976 break; 977 } 978 979 if (de == NULL || de->de_flags & DE_WHITEOUT) { 980 if ((nameiop == CREATE || nameiop == RENAME) && 981 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) { 982 cnp->cn_flags |= SAVENAME; 983 return (EJUSTRETURN); 984 } 985 return (ENOENT); 986 } 987 988 if (devfs_prison_check(de, td)) 989 return (ENOENT); 990 991 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) { 992 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); 993 if (error) 994 return (error); 995 if (*vpp == dvp) { 996 VREF(dvp); 997 *vpp = dvp; 998 return (0); 999 } 1000 } 1001 error = devfs_allocv(de, dvp->v_mount, cnp->cn_lkflags & LK_TYPE_MASK, 1002 vpp); 1003 *dm_unlock = 0; 1004 return (error); 1005} 1006 1007static int 1008devfs_lookup(struct vop_lookup_args *ap) 1009{ 1010 int j; 1011 struct devfs_mount *dmp; 1012 int dm_unlock; 1013 1014 if (devfs_populate_vp(ap->a_dvp) != 0) 1015 return (ENOTDIR); 1016 1017 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1018 dm_unlock = 1; 1019 j = devfs_lookupx(ap, &dm_unlock); 1020 if (dm_unlock == 1) 1021 sx_xunlock(&dmp->dm_lock); 1022 return (j); 1023} 1024 1025static int 1026devfs_mknod(struct vop_mknod_args *ap) 1027{ 1028 struct componentname *cnp; 1029 struct vnode *dvp, **vpp; 1030 struct devfs_dirent *dd, *de; 1031 struct devfs_mount *dmp; 1032 int error; 1033 1034 /* 1035 * The only type of node we should be creating here is a 1036 * character device, for anything else return EOPNOTSUPP. 1037 */ 1038 if (ap->a_vap->va_type != VCHR) 1039 return (EOPNOTSUPP); 1040 dvp = ap->a_dvp; 1041 dmp = VFSTODEVFS(dvp->v_mount); 1042 1043 cnp = ap->a_cnp; 1044 vpp = ap->a_vpp; 1045 dd = dvp->v_data; 1046 1047 error = ENOENT; 1048 sx_xlock(&dmp->dm_lock); 1049 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 1050 if (cnp->cn_namelen != de->de_dirent->d_namlen) 1051 continue; 1052 if (de->de_dirent->d_type == DT_CHR && 1053 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0) 1054 continue; 1055 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 1056 de->de_dirent->d_namlen) != 0) 1057 continue; 1058 if (de->de_flags & DE_WHITEOUT) 1059 break; 1060 goto notfound; 1061 } 1062 if (de == NULL) 1063 goto notfound; 1064 de->de_flags &= ~DE_WHITEOUT; 1065 error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp); 1066 return (error); 1067notfound: 1068 sx_xunlock(&dmp->dm_lock); 1069 return (error); 1070} 1071 1072/* ARGSUSED */ 1073static int 1074devfs_open(struct vop_open_args *ap) 1075{ 1076 struct thread *td = ap->a_td; 1077 struct vnode *vp = ap->a_vp; 1078 struct cdev *dev = vp->v_rdev; 1079 struct file *fp = ap->a_fp; 1080 int error, ref, vlocked; 1081 struct cdevsw *dsw; 1082 struct file *fpop; 1083 struct mtx *mtxp; 1084 1085 if (vp->v_type == VBLK) 1086 return (ENXIO); 1087 1088 if (dev == NULL) 1089 return (ENXIO); 1090 1091 /* Make this field valid before any I/O in d_open. */ 1092 if (dev->si_iosize_max == 0) 1093 dev->si_iosize_max = DFLTPHYS; 1094 1095 dsw = dev_refthread(dev, &ref); 1096 if (dsw == NULL) 1097 return (ENXIO); 1098 if (fp == NULL && dsw->d_fdopen != NULL) { 1099 dev_relthread(dev, ref); 1100 return (ENXIO); 1101 } 1102 1103 vlocked = VOP_ISLOCKED(vp); 1104 VOP_UNLOCK(vp, 0); 1105 1106 fpop = td->td_fpop; 1107 td->td_fpop = fp; 1108 if (fp != NULL) { 1109 fp->f_data = dev; 1110 fp->f_vnode = vp; 1111 } 1112 if (dsw->d_fdopen != NULL) 1113 error = dsw->d_fdopen(dev, ap->a_mode, td, fp); 1114 else 1115 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 1116 /* cleanup any cdevpriv upon error */ 1117 if (error != 0) 1118 devfs_clear_cdevpriv(); 1119 td->td_fpop = fpop; 1120 1121 vn_lock(vp, vlocked | LK_RETRY); 1122 dev_relthread(dev, ref); 1123 if (error != 0) { 1124 if (error == ERESTART) 1125 error = EINTR; 1126 return (error); 1127 } 1128 1129#if 0 /* /dev/console */ 1130 KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp")); 1131#else 1132 if (fp == NULL) 1133 return (error); 1134#endif 1135 if (fp->f_ops == &badfileops) 1136 finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f); 1137 mtxp = mtx_pool_find(mtxpool_sleep, fp); 1138 1139 /* 1140 * Hint to the dofilewrite() to not force the buffer draining 1141 * on the writer to the file. Most likely, the write would 1142 * not need normal buffers. 1143 */ 1144 mtx_lock(mtxp); 1145 fp->f_vnread_flags |= FDEVFS_VNODE; 1146 mtx_unlock(mtxp); 1147 return (error); 1148} 1149 1150static int 1151devfs_pathconf(struct vop_pathconf_args *ap) 1152{ 1153 1154 switch (ap->a_name) { 1155 case _PC_MAC_PRESENT: 1156#ifdef MAC 1157 /* 1158 * If MAC is enabled, devfs automatically supports 1159 * trivial non-persistant label storage. 1160 */ 1161 *ap->a_retval = 1; 1162#else 1163 *ap->a_retval = 0; 1164#endif 1165 return (0); 1166 default: 1167 return (vop_stdpathconf(ap)); 1168 } 1169 /* NOTREACHED */ 1170} 1171 1172/* ARGSUSED */ 1173static int 1174devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td) 1175{ 1176 struct cdev *dev; 1177 struct cdevsw *dsw; 1178 int error, ref; 1179 struct file *fpop; 1180 1181 fpop = td->td_fpop; 1182 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1183 if (error != 0) { 1184 error = vnops.fo_poll(fp, events, cred, td); 1185 return (error); 1186 } 1187 error = dsw->d_poll(dev, events, td); 1188 td->td_fpop = fpop; 1189 dev_relthread(dev, ref); 1190 return(error); 1191} 1192 1193/* 1194 * Print out the contents of a special device vnode. 1195 */ 1196static int 1197devfs_print(struct vop_print_args *ap) 1198{ 1199 1200 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev)); 1201 return (0); 1202} 1203 1204static int 1205devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred, 1206 int flags, struct thread *td) 1207{ 1208 struct cdev *dev; 1209 int ioflag, error, ref; 1210 ssize_t resid; 1211 struct cdevsw *dsw; 1212 struct file *fpop; 1213 1214 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1215 return (EINVAL); 1216 fpop = td->td_fpop; 1217 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1218 if (error != 0) { 1219 error = vnops.fo_read(fp, uio, cred, flags, td); 1220 return (error); 1221 } 1222 resid = uio->uio_resid; 1223 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT); 1224 if (ioflag & O_DIRECT) 1225 ioflag |= IO_DIRECT; 1226 1227 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1228 error = dsw->d_read(dev, uio, ioflag); 1229 if (uio->uio_resid != resid || (error == 0 && resid != 0)) 1230 devfs_timestamp(&dev->si_atime); 1231 td->td_fpop = fpop; 1232 dev_relthread(dev, ref); 1233 1234 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1235 return (error); 1236} 1237 1238static int 1239devfs_readdir(struct vop_readdir_args *ap) 1240{ 1241 int error; 1242 struct uio *uio; 1243 struct dirent *dp; 1244 struct devfs_dirent *dd; 1245 struct devfs_dirent *de; 1246 struct devfs_mount *dmp; 1247 off_t off; 1248 int *tmp_ncookies = NULL; 1249 1250 if (ap->a_vp->v_type != VDIR) 1251 return (ENOTDIR); 1252 1253 uio = ap->a_uio; 1254 if (uio->uio_offset < 0) 1255 return (EINVAL); 1256 1257 /* 1258 * XXX: This is a temporary hack to get around this filesystem not 1259 * supporting cookies. We store the location of the ncookies pointer 1260 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent() 1261 * and set the number of cookies to 0. We then set the pointer to 1262 * NULL so that vfs_read_dirent doesn't try to call realloc() on 1263 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies 1264 * pointer to its original location before returning to the caller. 1265 */ 1266 if (ap->a_ncookies != NULL) { 1267 tmp_ncookies = ap->a_ncookies; 1268 *ap->a_ncookies = 0; 1269 ap->a_ncookies = NULL; 1270 } 1271 1272 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1273 if (devfs_populate_vp(ap->a_vp) != 0) { 1274 if (tmp_ncookies != NULL) 1275 ap->a_ncookies = tmp_ncookies; 1276 return (EIO); 1277 } 1278 error = 0; 1279 de = ap->a_vp->v_data; 1280 off = 0; 1281 TAILQ_FOREACH(dd, &de->de_dlist, de_list) { 1282 KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__)); 1283 if (dd->de_flags & (DE_COVERED | DE_WHITEOUT)) 1284 continue; 1285 if (devfs_prison_check(dd, uio->uio_td)) 1286 continue; 1287 if (dd->de_dirent->d_type == DT_DIR) 1288 de = dd->de_dir; 1289 else 1290 de = dd; 1291 dp = dd->de_dirent; 1292 if (dp->d_reclen > uio->uio_resid) 1293 break; 1294 dp->d_fileno = de->de_inode; 1295 if (off >= uio->uio_offset) { 1296 error = vfs_read_dirent(ap, dp, off); 1297 if (error) 1298 break; 1299 } 1300 off += dp->d_reclen; 1301 } 1302 sx_xunlock(&dmp->dm_lock); 1303 uio->uio_offset = off; 1304 1305 /* 1306 * Restore ap->a_ncookies if it wasn't originally NULL in the first 1307 * place. 1308 */ 1309 if (tmp_ncookies != NULL) 1310 ap->a_ncookies = tmp_ncookies; 1311 1312 return (error); 1313} 1314 1315static int 1316devfs_readlink(struct vop_readlink_args *ap) 1317{ 1318 struct devfs_dirent *de; 1319 1320 de = ap->a_vp->v_data; 1321 return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio)); 1322} 1323 1324static int 1325devfs_reclaim(struct vop_reclaim_args *ap) 1326{ 1327 struct vnode *vp = ap->a_vp; 1328 struct devfs_dirent *de; 1329 struct cdev *dev; 1330 1331 mtx_lock(&devfs_de_interlock); 1332 de = vp->v_data; 1333 if (de != NULL) { 1334 de->de_vnode = NULL; 1335 vp->v_data = NULL; 1336 } 1337 mtx_unlock(&devfs_de_interlock); 1338 1339 vnode_destroy_vobject(vp); 1340 1341 VI_LOCK(vp); 1342 dev_lock(); 1343 dev = vp->v_rdev; 1344 vp->v_rdev = NULL; 1345 1346 if (dev == NULL) { 1347 dev_unlock(); 1348 VI_UNLOCK(vp); 1349 return (0); 1350 } 1351 1352 dev->si_usecount -= vp->v_usecount; 1353 dev_unlock(); 1354 VI_UNLOCK(vp); 1355 dev_rel(dev); 1356 return (0); 1357} 1358 1359static int 1360devfs_remove(struct vop_remove_args *ap) 1361{ 1362 struct vnode *dvp = ap->a_dvp; 1363 struct vnode *vp = ap->a_vp; 1364 struct devfs_dirent *dd; 1365 struct devfs_dirent *de, *de_covered; 1366 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); 1367 1368 ASSERT_VOP_ELOCKED(dvp, "devfs_remove"); 1369 ASSERT_VOP_ELOCKED(vp, "devfs_remove"); 1370 1371 sx_xlock(&dmp->dm_lock); 1372 dd = ap->a_dvp->v_data; 1373 de = vp->v_data; 1374 if (de->de_cdp == NULL) { 1375 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 1376 if (de->de_dirent->d_type == DT_LNK) { 1377 de_covered = devfs_find(dd, de->de_dirent->d_name, 1378 de->de_dirent->d_namlen, 0); 1379 if (de_covered != NULL) 1380 de_covered->de_flags &= ~DE_COVERED; 1381 } 1382 /* We need to unlock dvp because devfs_delete() may lock it. */ 1383 VOP_UNLOCK(vp, 0); 1384 if (dvp != vp) 1385 VOP_UNLOCK(dvp, 0); 1386 devfs_delete(dmp, de, 0); 1387 sx_xunlock(&dmp->dm_lock); 1388 if (dvp != vp) 1389 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1390 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1391 } else { 1392 de->de_flags |= DE_WHITEOUT; 1393 sx_xunlock(&dmp->dm_lock); 1394 } 1395 return (0); 1396} 1397 1398/* 1399 * Revoke is called on a tty when a terminal session ends. The vnode 1400 * is orphaned by setting v_op to deadfs so we need to let go of it 1401 * as well so that we create a new one next time around. 1402 * 1403 */ 1404static int 1405devfs_revoke(struct vop_revoke_args *ap) 1406{ 1407 struct vnode *vp = ap->a_vp, *vp2; 1408 struct cdev *dev; 1409 struct cdev_priv *cdp; 1410 struct devfs_dirent *de; 1411 int i; 1412 1413 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL")); 1414 1415 dev = vp->v_rdev; 1416 cdp = cdev2priv(dev); 1417 1418 dev_lock(); 1419 cdp->cdp_inuse++; 1420 dev_unlock(); 1421 1422 vhold(vp); 1423 vgone(vp); 1424 vdrop(vp); 1425 1426 VOP_UNLOCK(vp,0); 1427 loop: 1428 for (;;) { 1429 mtx_lock(&devfs_de_interlock); 1430 dev_lock(); 1431 vp2 = NULL; 1432 for (i = 0; i <= cdp->cdp_maxdirent; i++) { 1433 de = cdp->cdp_dirents[i]; 1434 if (de == NULL) 1435 continue; 1436 1437 vp2 = de->de_vnode; 1438 if (vp2 != NULL) { 1439 dev_unlock(); 1440 VI_LOCK(vp2); 1441 mtx_unlock(&devfs_de_interlock); 1442 if (vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK, 1443 curthread)) 1444 goto loop; 1445 vhold(vp2); 1446 vgone(vp2); 1447 vdrop(vp2); 1448 vput(vp2); 1449 break; 1450 } 1451 } 1452 if (vp2 != NULL) { 1453 continue; 1454 } 1455 dev_unlock(); 1456 mtx_unlock(&devfs_de_interlock); 1457 break; 1458 } 1459 dev_lock(); 1460 cdp->cdp_inuse--; 1461 if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) { 1462 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); 1463 dev_unlock(); 1464 dev_rel(&cdp->cdp_c); 1465 } else 1466 dev_unlock(); 1467 1468 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1469 return (0); 1470} 1471 1472static int 1473devfs_rioctl(struct vop_ioctl_args *ap) 1474{ 1475 struct vnode *vp; 1476 struct devfs_mount *dmp; 1477 int error; 1478 1479 vp = ap->a_vp; 1480 vn_lock(vp, LK_SHARED | LK_RETRY); 1481 if (vp->v_iflag & VI_DOOMED) { 1482 VOP_UNLOCK(vp, 0); 1483 return (EBADF); 1484 } 1485 dmp = VFSTODEVFS(vp->v_mount); 1486 sx_xlock(&dmp->dm_lock); 1487 VOP_UNLOCK(vp, 0); 1488 DEVFS_DMP_HOLD(dmp); 1489 devfs_populate(dmp); 1490 if (DEVFS_DMP_DROP(dmp)) { 1491 sx_xunlock(&dmp->dm_lock); 1492 devfs_unmount_final(dmp); 1493 return (ENOENT); 1494 } 1495 error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td); 1496 sx_xunlock(&dmp->dm_lock); 1497 return (error); 1498} 1499 1500static int 1501devfs_rread(struct vop_read_args *ap) 1502{ 1503 1504 if (ap->a_vp->v_type != VDIR) 1505 return (EINVAL); 1506 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL)); 1507} 1508 1509static int 1510devfs_setattr(struct vop_setattr_args *ap) 1511{ 1512 struct devfs_dirent *de; 1513 struct vattr *vap; 1514 struct vnode *vp; 1515 struct thread *td; 1516 int c, error; 1517 uid_t uid; 1518 gid_t gid; 1519 1520 vap = ap->a_vap; 1521 vp = ap->a_vp; 1522 td = curthread; 1523 if ((vap->va_type != VNON) || 1524 (vap->va_nlink != VNOVAL) || 1525 (vap->va_fsid != VNOVAL) || 1526 (vap->va_fileid != VNOVAL) || 1527 (vap->va_blocksize != VNOVAL) || 1528 (vap->va_flags != VNOVAL && vap->va_flags != 0) || 1529 (vap->va_rdev != VNOVAL) || 1530 ((int)vap->va_bytes != VNOVAL) || 1531 (vap->va_gen != VNOVAL)) { 1532 return (EINVAL); 1533 } 1534 1535 de = vp->v_data; 1536 if (vp->v_type == VDIR) 1537 de = de->de_dir; 1538 1539 error = c = 0; 1540 if (vap->va_uid == (uid_t)VNOVAL) 1541 uid = de->de_uid; 1542 else 1543 uid = vap->va_uid; 1544 if (vap->va_gid == (gid_t)VNOVAL) 1545 gid = de->de_gid; 1546 else 1547 gid = vap->va_gid; 1548 if (uid != de->de_uid || gid != de->de_gid) { 1549 if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid || 1550 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) { 1551 error = priv_check(td, PRIV_VFS_CHOWN); 1552 if (error) 1553 return (error); 1554 } 1555 de->de_uid = uid; 1556 de->de_gid = gid; 1557 c = 1; 1558 } 1559 1560 if (vap->va_mode != (mode_t)VNOVAL) { 1561 if (ap->a_cred->cr_uid != de->de_uid) { 1562 error = priv_check(td, PRIV_VFS_ADMIN); 1563 if (error) 1564 return (error); 1565 } 1566 de->de_mode = vap->va_mode; 1567 c = 1; 1568 } 1569 1570 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 1571 error = vn_utimes_perm(vp, vap, ap->a_cred, td); 1572 if (error != 0) 1573 return (error); 1574 if (vap->va_atime.tv_sec != VNOVAL) { 1575 if (vp->v_type == VCHR) 1576 vp->v_rdev->si_atime = vap->va_atime; 1577 else 1578 de->de_atime = vap->va_atime; 1579 } 1580 if (vap->va_mtime.tv_sec != VNOVAL) { 1581 if (vp->v_type == VCHR) 1582 vp->v_rdev->si_mtime = vap->va_mtime; 1583 else 1584 de->de_mtime = vap->va_mtime; 1585 } 1586 c = 1; 1587 } 1588 1589 if (c) { 1590 if (vp->v_type == VCHR) 1591 vfs_timestamp(&vp->v_rdev->si_ctime); 1592 else 1593 vfs_timestamp(&de->de_mtime); 1594 } 1595 return (0); 1596} 1597 1598#ifdef MAC 1599static int 1600devfs_setlabel(struct vop_setlabel_args *ap) 1601{ 1602 struct vnode *vp; 1603 struct devfs_dirent *de; 1604 1605 vp = ap->a_vp; 1606 de = vp->v_data; 1607 1608 mac_vnode_relabel(ap->a_cred, vp, ap->a_label); 1609 mac_devfs_update(vp->v_mount, de, vp); 1610 1611 return (0); 1612} 1613#endif 1614 1615static int 1616devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td) 1617{ 1618 1619 return (vnops.fo_stat(fp, sb, cred, td)); 1620} 1621 1622static int 1623devfs_symlink(struct vop_symlink_args *ap) 1624{ 1625 int i, error; 1626 struct devfs_dirent *dd; 1627 struct devfs_dirent *de, *de_covered, *de_dotdot; 1628 struct devfs_mount *dmp; 1629 1630 error = priv_check(curthread, PRIV_DEVFS_SYMLINK); 1631 if (error) 1632 return(error); 1633 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1634 if (devfs_populate_vp(ap->a_dvp) != 0) 1635 return (ENOENT); 1636 1637 dd = ap->a_dvp->v_data; 1638 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen); 1639 de->de_flags = DE_USER; 1640 de->de_uid = 0; 1641 de->de_gid = 0; 1642 de->de_mode = 0755; 1643 de->de_inode = alloc_unr(devfs_inos); 1644 de->de_dir = dd; 1645 de->de_dirent->d_type = DT_LNK; 1646 i = strlen(ap->a_target) + 1; 1647 de->de_symlink = malloc(i, M_DEVFS, M_WAITOK); 1648 bcopy(ap->a_target, de->de_symlink, i); 1649#ifdef MAC 1650 mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de); 1651#endif 1652 de_covered = devfs_find(dd, de->de_dirent->d_name, 1653 de->de_dirent->d_namlen, 0); 1654 if (de_covered != NULL) { 1655 if ((de_covered->de_flags & DE_USER) != 0) { 1656 devfs_delete(dmp, de, DEVFS_DEL_NORECURSE); 1657 sx_xunlock(&dmp->dm_lock); 1658 return (EEXIST); 1659 } 1660 KASSERT((de_covered->de_flags & DE_COVERED) == 0, 1661 ("devfs_symlink: entry %p already covered", de_covered)); 1662 de_covered->de_flags |= DE_COVERED; 1663 } 1664 1665 de_dotdot = TAILQ_FIRST(&dd->de_dlist); /* "." */ 1666 de_dotdot = TAILQ_NEXT(de_dotdot, de_list); /* ".." */ 1667 TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list); 1668 devfs_dir_ref_de(dmp, dd); 1669 devfs_rules_apply(dmp, de); 1670 1671 return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp)); 1672} 1673 1674static int 1675devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td) 1676{ 1677 1678 return (vnops.fo_truncate(fp, length, cred, td)); 1679} 1680 1681static int 1682devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred, 1683 int flags, struct thread *td) 1684{ 1685 struct cdev *dev; 1686 int error, ioflag, ref; 1687 ssize_t resid; 1688 struct cdevsw *dsw; 1689 struct file *fpop; 1690 1691 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1692 return (EINVAL); 1693 fpop = td->td_fpop; 1694 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1695 if (error != 0) { 1696 error = vnops.fo_write(fp, uio, cred, flags, td); 1697 return (error); 1698 } 1699 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td)); 1700 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC); 1701 if (ioflag & O_DIRECT) 1702 ioflag |= IO_DIRECT; 1703 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1704 1705 resid = uio->uio_resid; 1706 1707 error = dsw->d_write(dev, uio, ioflag); 1708 if (uio->uio_resid != resid || (error == 0 && resid != 0)) { 1709 devfs_timestamp(&dev->si_ctime); 1710 dev->si_mtime = dev->si_ctime; 1711 } 1712 td->td_fpop = fpop; 1713 dev_relthread(dev, ref); 1714 1715 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1716 return (error); 1717} 1718 1719dev_t 1720dev2udev(struct cdev *x) 1721{ 1722 if (x == NULL) 1723 return (NODEV); 1724 return (cdev2priv(x)->cdp_inode); 1725} 1726 1727static struct fileops devfs_ops_f = { 1728 .fo_read = devfs_read_f, 1729 .fo_write = devfs_write_f, 1730 .fo_truncate = devfs_truncate_f, 1731 .fo_ioctl = devfs_ioctl_f, 1732 .fo_poll = devfs_poll_f, 1733 .fo_kqfilter = devfs_kqfilter_f, 1734 .fo_stat = devfs_stat_f, 1735 .fo_close = devfs_close_f, 1736 .fo_chmod = vn_chmod, 1737 .fo_chown = vn_chown, 1738 .fo_sendfile = vn_sendfile, 1739 .fo_seek = vn_seek, 1740 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE 1741}; 1742 1743static struct vop_vector devfs_vnodeops = { 1744 .vop_default = &default_vnodeops, 1745 1746 .vop_access = devfs_access, 1747 .vop_getattr = devfs_getattr, 1748 .vop_ioctl = devfs_rioctl, 1749 .vop_lookup = devfs_lookup, 1750 .vop_mknod = devfs_mknod, 1751 .vop_pathconf = devfs_pathconf, 1752 .vop_read = devfs_rread, 1753 .vop_readdir = devfs_readdir, 1754 .vop_readlink = devfs_readlink, 1755 .vop_reclaim = devfs_reclaim, 1756 .vop_remove = devfs_remove, 1757 .vop_revoke = devfs_revoke, 1758 .vop_setattr = devfs_setattr, 1759#ifdef MAC 1760 .vop_setlabel = devfs_setlabel, 1761#endif 1762 .vop_symlink = devfs_symlink, 1763 .vop_vptocnp = devfs_vptocnp, 1764}; 1765 1766struct vop_vector devfs_specops = { 1767 .vop_default = &default_vnodeops, 1768 1769 .vop_access = devfs_access, 1770 .vop_bmap = VOP_PANIC, 1771 .vop_close = devfs_close, 1772 .vop_create = VOP_PANIC, 1773 .vop_fsync = devfs_fsync, 1774 .vop_getattr = devfs_getattr, 1775 .vop_link = VOP_PANIC, 1776 .vop_mkdir = VOP_PANIC, 1777 .vop_mknod = VOP_PANIC, 1778 .vop_open = devfs_open, 1779 .vop_pathconf = devfs_pathconf, 1780 .vop_poll = dead_poll, 1781 .vop_print = devfs_print, 1782 .vop_read = dead_read, 1783 .vop_readdir = VOP_PANIC, 1784 .vop_readlink = VOP_PANIC, 1785 .vop_reallocblks = VOP_PANIC, 1786 .vop_reclaim = devfs_reclaim, 1787 .vop_remove = devfs_remove, 1788 .vop_rename = VOP_PANIC, 1789 .vop_revoke = devfs_revoke, 1790 .vop_rmdir = VOP_PANIC, 1791 .vop_setattr = devfs_setattr, 1792#ifdef MAC 1793 .vop_setlabel = devfs_setlabel, 1794#endif 1795 .vop_strategy = VOP_PANIC, 1796 .vop_symlink = VOP_PANIC, 1797 .vop_vptocnp = devfs_vptocnp, 1798 .vop_write = dead_write, 1799}; 1800 1801/* 1802 * Our calling convention to the device drivers used to be that we passed 1803 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_ 1804 * flags instead since that's what open(), close() and ioctl() takes and 1805 * we don't really want vnode.h in device drivers. 1806 * We solved the source compatibility by redefining some vnode flags to 1807 * be the same as the fcntl ones and by sending down the bitwise OR of 1808 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody 1809 * pulls the rug out under this. 1810 */ 1811CTASSERT(O_NONBLOCK == IO_NDELAY); 1812CTASSERT(O_FSYNC == IO_SYNC); 1813