devfs_vnops.c revision 277746
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 277746 2015-01-26 11:37:16Z 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/time.h> 61#include <sys/ttycom.h> 62#include <sys/unistd.h> 63#include <sys/vnode.h> 64 65static struct vop_vector devfs_vnodeops; 66static struct vop_vector devfs_specops; 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 83static int 84devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp, 85 int *ref) 86{ 87 88 *dswp = devvn_refthread(fp->f_vnode, devp, ref); 89 if (*devp != fp->f_data) { 90 if (*dswp != NULL) 91 dev_relthread(*devp, *ref); 92 return (ENXIO); 93 } 94 KASSERT((*devp)->si_refcount > 0, 95 ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp))); 96 if (*dswp == NULL) 97 return (ENXIO); 98 curthread->td_fpop = fp; 99 return (0); 100} 101 102int 103devfs_get_cdevpriv(void **datap) 104{ 105 struct file *fp; 106 struct cdev_privdata *p; 107 int error; 108 109 fp = curthread->td_fpop; 110 if (fp == NULL) 111 return (EBADF); 112 p = fp->f_cdevpriv; 113 if (p != NULL) { 114 error = 0; 115 *datap = p->cdpd_data; 116 } else 117 error = ENOENT; 118 return (error); 119} 120 121int 122devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t priv_dtr) 123{ 124 struct file *fp; 125 struct cdev_priv *cdp; 126 struct cdev_privdata *p; 127 int error; 128 129 fp = curthread->td_fpop; 130 if (fp == NULL) 131 return (ENOENT); 132 cdp = cdev2priv((struct cdev *)fp->f_data); 133 p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK); 134 p->cdpd_data = priv; 135 p->cdpd_dtr = priv_dtr; 136 p->cdpd_fp = fp; 137 mtx_lock(&cdevpriv_mtx); 138 if (fp->f_cdevpriv == NULL) { 139 LIST_INSERT_HEAD(&cdp->cdp_fdpriv, p, cdpd_list); 140 fp->f_cdevpriv = p; 141 mtx_unlock(&cdevpriv_mtx); 142 error = 0; 143 } else { 144 mtx_unlock(&cdevpriv_mtx); 145 free(p, M_CDEVPDATA); 146 error = EBUSY; 147 } 148 return (error); 149} 150 151void 152devfs_destroy_cdevpriv(struct cdev_privdata *p) 153{ 154 155 mtx_assert(&cdevpriv_mtx, MA_OWNED); 156 p->cdpd_fp->f_cdevpriv = NULL; 157 LIST_REMOVE(p, cdpd_list); 158 mtx_unlock(&cdevpriv_mtx); 159 (p->cdpd_dtr)(p->cdpd_data); 160 free(p, M_CDEVPDATA); 161} 162 163void 164devfs_fpdrop(struct file *fp) 165{ 166 struct cdev_privdata *p; 167 168 mtx_lock(&cdevpriv_mtx); 169 if ((p = fp->f_cdevpriv) == NULL) { 170 mtx_unlock(&cdevpriv_mtx); 171 return; 172 } 173 devfs_destroy_cdevpriv(p); 174} 175 176void 177devfs_clear_cdevpriv(void) 178{ 179 struct file *fp; 180 181 fp = curthread->td_fpop; 182 if (fp == NULL) 183 return; 184 devfs_fpdrop(fp); 185} 186 187/* 188 * On success devfs_populate_vp() returns with dmp->dm_lock held. 189 */ 190static int 191devfs_populate_vp(struct vnode *vp) 192{ 193 struct devfs_dirent *de; 194 struct devfs_mount *dmp; 195 int locked; 196 197 ASSERT_VOP_LOCKED(vp, "devfs_populate_vp"); 198 199 dmp = VFSTODEVFS(vp->v_mount); 200 locked = VOP_ISLOCKED(vp); 201 202 sx_xlock(&dmp->dm_lock); 203 DEVFS_DMP_HOLD(dmp); 204 205 /* Can't call devfs_populate() with the vnode lock held. */ 206 VOP_UNLOCK(vp, 0); 207 devfs_populate(dmp); 208 209 sx_xunlock(&dmp->dm_lock); 210 vn_lock(vp, locked | LK_RETRY); 211 sx_xlock(&dmp->dm_lock); 212 if (DEVFS_DMP_DROP(dmp)) { 213 sx_xunlock(&dmp->dm_lock); 214 devfs_unmount_final(dmp); 215 return (EBADF); 216 } 217 if ((vp->v_iflag & VI_DOOMED) != 0) { 218 sx_xunlock(&dmp->dm_lock); 219 return (EBADF); 220 } 221 de = vp->v_data; 222 KASSERT(de != NULL, 223 ("devfs_populate_vp: vp->v_data == NULL but vnode not doomed")); 224 if ((de->de_flags & DE_DOOMED) != 0) { 225 sx_xunlock(&dmp->dm_lock); 226 return (EBADF); 227 } 228 229 return (0); 230} 231 232static int 233devfs_vptocnp(struct vop_vptocnp_args *ap) 234{ 235 struct vnode *vp = ap->a_vp; 236 struct vnode **dvp = ap->a_vpp; 237 struct devfs_mount *dmp; 238 char *buf = ap->a_buf; 239 int *buflen = ap->a_buflen; 240 struct devfs_dirent *dd, *de; 241 int i, error; 242 243 dmp = VFSTODEVFS(vp->v_mount); 244 245 error = devfs_populate_vp(vp); 246 if (error != 0) 247 return (error); 248 249 i = *buflen; 250 dd = vp->v_data; 251 252 if (vp->v_type == VCHR) { 253 i -= strlen(dd->de_cdp->cdp_c.si_name); 254 if (i < 0) { 255 error = ENOMEM; 256 goto finished; 257 } 258 bcopy(dd->de_cdp->cdp_c.si_name, buf + i, 259 strlen(dd->de_cdp->cdp_c.si_name)); 260 de = dd->de_dir; 261 } else if (vp->v_type == VDIR) { 262 if (dd == dmp->dm_rootdir) { 263 *dvp = vp; 264 vref(*dvp); 265 goto finished; 266 } 267 i -= dd->de_dirent->d_namlen; 268 if (i < 0) { 269 error = ENOMEM; 270 goto finished; 271 } 272 bcopy(dd->de_dirent->d_name, buf + i, 273 dd->de_dirent->d_namlen); 274 de = dd; 275 } else { 276 error = ENOENT; 277 goto finished; 278 } 279 *buflen = i; 280 de = devfs_parent_dirent(de); 281 if (de == NULL) { 282 error = ENOENT; 283 goto finished; 284 } 285 mtx_lock(&devfs_de_interlock); 286 *dvp = de->de_vnode; 287 if (*dvp != NULL) { 288 VI_LOCK(*dvp); 289 mtx_unlock(&devfs_de_interlock); 290 vholdl(*dvp); 291 VI_UNLOCK(*dvp); 292 vref(*dvp); 293 vdrop(*dvp); 294 } else { 295 mtx_unlock(&devfs_de_interlock); 296 error = ENOENT; 297 } 298finished: 299 sx_xunlock(&dmp->dm_lock); 300 return (error); 301} 302 303/* 304 * Construct the fully qualified path name relative to the mountpoint. 305 * If a NULL cnp is provided, no '/' is appended to the resulting path. 306 */ 307char * 308devfs_fqpn(char *buf, struct devfs_mount *dmp, struct devfs_dirent *dd, 309 struct componentname *cnp) 310{ 311 int i; 312 struct devfs_dirent *de; 313 314 sx_assert(&dmp->dm_lock, SA_LOCKED); 315 316 i = SPECNAMELEN; 317 buf[i] = '\0'; 318 if (cnp != NULL) 319 i -= cnp->cn_namelen; 320 if (i < 0) 321 return (NULL); 322 if (cnp != NULL) 323 bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen); 324 de = dd; 325 while (de != dmp->dm_rootdir) { 326 if (cnp != NULL || i < SPECNAMELEN) { 327 i--; 328 if (i < 0) 329 return (NULL); 330 buf[i] = '/'; 331 } 332 i -= de->de_dirent->d_namlen; 333 if (i < 0) 334 return (NULL); 335 bcopy(de->de_dirent->d_name, buf + i, 336 de->de_dirent->d_namlen); 337 de = devfs_parent_dirent(de); 338 if (de == NULL) 339 return (NULL); 340 } 341 return (buf + i); 342} 343 344static int 345devfs_allocv_drop_refs(int drop_dm_lock, struct devfs_mount *dmp, 346 struct devfs_dirent *de) 347{ 348 int not_found; 349 350 not_found = 0; 351 if (de->de_flags & DE_DOOMED) 352 not_found = 1; 353 if (DEVFS_DE_DROP(de)) { 354 KASSERT(not_found == 1, ("DEVFS de dropped but not doomed")); 355 devfs_dirent_free(de); 356 } 357 if (DEVFS_DMP_DROP(dmp)) { 358 KASSERT(not_found == 1, 359 ("DEVFS mount struct freed before dirent")); 360 not_found = 2; 361 sx_xunlock(&dmp->dm_lock); 362 devfs_unmount_final(dmp); 363 } 364 if (not_found == 1 || (drop_dm_lock && not_found != 2)) 365 sx_unlock(&dmp->dm_lock); 366 return (not_found); 367} 368 369static void 370devfs_insmntque_dtr(struct vnode *vp, void *arg) 371{ 372 struct devfs_dirent *de; 373 374 de = (struct devfs_dirent *)arg; 375 mtx_lock(&devfs_de_interlock); 376 vp->v_data = NULL; 377 de->de_vnode = NULL; 378 mtx_unlock(&devfs_de_interlock); 379 vgone(vp); 380 vput(vp); 381} 382 383/* 384 * devfs_allocv shall be entered with dmp->dm_lock held, and it drops 385 * it on return. 386 */ 387int 388devfs_allocv(struct devfs_dirent *de, struct mount *mp, int lockmode, 389 struct vnode **vpp) 390{ 391 int error; 392 struct vnode *vp; 393 struct cdev *dev; 394 struct devfs_mount *dmp; 395 struct cdevsw *dsw; 396 397 dmp = VFSTODEVFS(mp); 398 if (de->de_flags & DE_DOOMED) { 399 sx_xunlock(&dmp->dm_lock); 400 return (ENOENT); 401 } 402loop: 403 DEVFS_DE_HOLD(de); 404 DEVFS_DMP_HOLD(dmp); 405 mtx_lock(&devfs_de_interlock); 406 vp = de->de_vnode; 407 if (vp != NULL) { 408 VI_LOCK(vp); 409 mtx_unlock(&devfs_de_interlock); 410 sx_xunlock(&dmp->dm_lock); 411 vget(vp, lockmode | LK_INTERLOCK | LK_RETRY, curthread); 412 sx_xlock(&dmp->dm_lock); 413 if (devfs_allocv_drop_refs(0, dmp, de)) { 414 vput(vp); 415 return (ENOENT); 416 } 417 else if ((vp->v_iflag & VI_DOOMED) != 0) { 418 mtx_lock(&devfs_de_interlock); 419 if (de->de_vnode == vp) { 420 de->de_vnode = NULL; 421 vp->v_data = NULL; 422 } 423 mtx_unlock(&devfs_de_interlock); 424 vput(vp); 425 goto loop; 426 } 427 sx_xunlock(&dmp->dm_lock); 428 *vpp = vp; 429 return (0); 430 } 431 mtx_unlock(&devfs_de_interlock); 432 if (de->de_dirent->d_type == DT_CHR) { 433 if (!(de->de_cdp->cdp_flags & CDP_ACTIVE)) { 434 devfs_allocv_drop_refs(1, dmp, de); 435 return (ENOENT); 436 } 437 dev = &de->de_cdp->cdp_c; 438 } else { 439 dev = NULL; 440 } 441 error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp); 442 if (error != 0) { 443 devfs_allocv_drop_refs(1, dmp, de); 444 printf("devfs_allocv: failed to allocate new vnode\n"); 445 return (error); 446 } 447 448 if (de->de_dirent->d_type == DT_CHR) { 449 vp->v_type = VCHR; 450 VI_LOCK(vp); 451 dev_lock(); 452 dev_refl(dev); 453 /* XXX: v_rdev should be protect by vnode lock */ 454 vp->v_rdev = dev; 455 KASSERT(vp->v_usecount == 1, 456 ("%s %d (%d)\n", __func__, __LINE__, vp->v_usecount)); 457 dev->si_usecount += vp->v_usecount; 458 /* Special casing of ttys for deadfs. Probably redundant. */ 459 dsw = dev->si_devsw; 460 if (dsw != NULL && (dsw->d_flags & D_TTY) != 0) 461 vp->v_vflag |= VV_ISTTY; 462 dev_unlock(); 463 VI_UNLOCK(vp); 464 if ((dev->si_flags & SI_ETERNAL) != 0) 465 vp->v_vflag |= VV_ETERNALDEV; 466 vp->v_op = &devfs_specops; 467 } else if (de->de_dirent->d_type == DT_DIR) { 468 vp->v_type = VDIR; 469 } else if (de->de_dirent->d_type == DT_LNK) { 470 vp->v_type = VLNK; 471 } else { 472 vp->v_type = VBAD; 473 } 474 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWITNESS); 475 VN_LOCK_ASHARE(vp); 476 mtx_lock(&devfs_de_interlock); 477 vp->v_data = de; 478 de->de_vnode = vp; 479 mtx_unlock(&devfs_de_interlock); 480 error = insmntque1(vp, mp, devfs_insmntque_dtr, de); 481 if (error != 0) { 482 (void) devfs_allocv_drop_refs(1, dmp, de); 483 return (error); 484 } 485 if (devfs_allocv_drop_refs(0, dmp, de)) { 486 vput(vp); 487 return (ENOENT); 488 } 489#ifdef MAC 490 mac_devfs_vnode_associate(mp, de, vp); 491#endif 492 sx_xunlock(&dmp->dm_lock); 493 *vpp = vp; 494 return (0); 495} 496 497static int 498devfs_access(struct vop_access_args *ap) 499{ 500 struct vnode *vp = ap->a_vp; 501 struct devfs_dirent *de; 502 int error; 503 504 de = vp->v_data; 505 if (vp->v_type == VDIR) 506 de = de->de_dir; 507 508 error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid, 509 ap->a_accmode, ap->a_cred, NULL); 510 if (error == 0) 511 return (0); 512 if (error != EACCES) 513 return (error); 514 /* We do, however, allow access to the controlling terminal */ 515 if (!(ap->a_td->td_proc->p_flag & P_CONTROLT)) 516 return (error); 517 if (ap->a_td->td_proc->p_session->s_ttydp == de->de_cdp) 518 return (0); 519 return (error); 520} 521 522/* ARGSUSED */ 523static int 524devfs_close(struct vop_close_args *ap) 525{ 526 struct vnode *vp = ap->a_vp, *oldvp; 527 struct thread *td = ap->a_td; 528 struct cdev *dev = vp->v_rdev; 529 struct cdevsw *dsw; 530 int vp_locked, error, ref; 531 532 /* 533 * XXX: Don't call d_close() if we were called because of 534 * XXX: insmntque1() failure. 535 */ 536 if (vp->v_data == NULL) 537 return (0); 538 539 /* 540 * Hack: a tty device that is a controlling terminal 541 * has a reference from the session structure. 542 * We cannot easily tell that a character device is 543 * a controlling terminal, unless it is the closing 544 * process' controlling terminal. In that case, 545 * if the reference count is 2 (this last descriptor 546 * plus the session), release the reference from the session. 547 */ 548 oldvp = NULL; 549 sx_xlock(&proctree_lock); 550 if (td && vp == td->td_proc->p_session->s_ttyvp) { 551 SESS_LOCK(td->td_proc->p_session); 552 VI_LOCK(vp); 553 if (count_dev(dev) == 2 && (vp->v_iflag & VI_DOOMED) == 0) { 554 td->td_proc->p_session->s_ttyvp = NULL; 555 td->td_proc->p_session->s_ttydp = NULL; 556 oldvp = vp; 557 } 558 VI_UNLOCK(vp); 559 SESS_UNLOCK(td->td_proc->p_session); 560 } 561 sx_xunlock(&proctree_lock); 562 if (oldvp != NULL) 563 vrele(oldvp); 564 /* 565 * We do not want to really close the device if it 566 * is still in use unless we are trying to close it 567 * forcibly. Since every use (buffer, vnode, swap, cmap) 568 * holds a reference to the vnode, and because we mark 569 * any other vnodes that alias this device, when the 570 * sum of the reference counts on all the aliased 571 * vnodes descends to one, we are on last close. 572 */ 573 dsw = dev_refthread(dev, &ref); 574 if (dsw == NULL) 575 return (ENXIO); 576 VI_LOCK(vp); 577 if (vp->v_iflag & VI_DOOMED) { 578 /* Forced close. */ 579 } else if (dsw->d_flags & D_TRACKCLOSE) { 580 /* Keep device updated on status. */ 581 } else if (count_dev(dev) > 1) { 582 VI_UNLOCK(vp); 583 dev_relthread(dev, ref); 584 return (0); 585 } 586 vholdl(vp); 587 VI_UNLOCK(vp); 588 vp_locked = VOP_ISLOCKED(vp); 589 VOP_UNLOCK(vp, 0); 590 KASSERT(dev->si_refcount > 0, 591 ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev))); 592 error = dsw->d_close(dev, ap->a_fflag, S_IFCHR, td); 593 dev_relthread(dev, ref); 594 vn_lock(vp, vp_locked | LK_RETRY); 595 vdrop(vp); 596 return (error); 597} 598 599static int 600devfs_close_f(struct file *fp, struct thread *td) 601{ 602 int error; 603 struct file *fpop; 604 605 /* 606 * NB: td may be NULL if this descriptor is closed due to 607 * garbage collection from a closed UNIX domain socket. 608 */ 609 fpop = curthread->td_fpop; 610 curthread->td_fpop = fp; 611 error = vnops.fo_close(fp, td); 612 curthread->td_fpop = fpop; 613 614 /* 615 * The f_cdevpriv cannot be assigned non-NULL value while we 616 * are destroying the file. 617 */ 618 if (fp->f_cdevpriv != NULL) 619 devfs_fpdrop(fp); 620 return (error); 621} 622 623static int 624devfs_fsync(struct vop_fsync_args *ap) 625{ 626 int error; 627 struct bufobj *bo; 628 struct devfs_dirent *de; 629 630 if (!vn_isdisk(ap->a_vp, &error)) { 631 bo = &ap->a_vp->v_bufobj; 632 de = ap->a_vp->v_data; 633 if (error == ENXIO && bo->bo_dirty.bv_cnt > 0) { 634 printf("Device %s went missing before all of the data " 635 "could be written to it; expect data loss.\n", 636 de->de_dirent->d_name); 637 638 error = vop_stdfsync(ap); 639 if (bo->bo_dirty.bv_cnt != 0 || error != 0) 640 panic("devfs_fsync: vop_stdfsync failed."); 641 } 642 643 return (0); 644 } 645 646 return (vop_stdfsync(ap)); 647} 648 649static int 650devfs_getattr(struct vop_getattr_args *ap) 651{ 652 struct vnode *vp = ap->a_vp; 653 struct vattr *vap = ap->a_vap; 654 int error; 655 struct devfs_dirent *de; 656 struct devfs_mount *dmp; 657 struct cdev *dev; 658 659 error = devfs_populate_vp(vp); 660 if (error != 0) 661 return (error); 662 663 dmp = VFSTODEVFS(vp->v_mount); 664 sx_xunlock(&dmp->dm_lock); 665 666 de = vp->v_data; 667 KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp)); 668 if (vp->v_type == VDIR) { 669 de = de->de_dir; 670 KASSERT(de != NULL, 671 ("Null dir dirent in devfs_getattr vp=%p", vp)); 672 } 673 vap->va_uid = de->de_uid; 674 vap->va_gid = de->de_gid; 675 vap->va_mode = de->de_mode; 676 if (vp->v_type == VLNK) 677 vap->va_size = strlen(de->de_symlink); 678 else if (vp->v_type == VDIR) 679 vap->va_size = vap->va_bytes = DEV_BSIZE; 680 else 681 vap->va_size = 0; 682 if (vp->v_type != VDIR) 683 vap->va_bytes = 0; 684 vap->va_blocksize = DEV_BSIZE; 685 vap->va_type = vp->v_type; 686 687#define fix(aa) \ 688 do { \ 689 if ((aa).tv_sec <= 3600) { \ 690 (aa).tv_sec = boottime.tv_sec; \ 691 (aa).tv_nsec = boottime.tv_usec * 1000; \ 692 } \ 693 } while (0) 694 695 if (vp->v_type != VCHR) { 696 fix(de->de_atime); 697 vap->va_atime = de->de_atime; 698 fix(de->de_mtime); 699 vap->va_mtime = de->de_mtime; 700 fix(de->de_ctime); 701 vap->va_ctime = de->de_ctime; 702 } else { 703 dev = vp->v_rdev; 704 fix(dev->si_atime); 705 vap->va_atime = dev->si_atime; 706 fix(dev->si_mtime); 707 vap->va_mtime = dev->si_mtime; 708 fix(dev->si_ctime); 709 vap->va_ctime = dev->si_ctime; 710 711 vap->va_rdev = cdev2priv(dev)->cdp_inode; 712 } 713 vap->va_gen = 0; 714 vap->va_flags = 0; 715 vap->va_filerev = 0; 716 vap->va_nlink = de->de_links; 717 vap->va_fileid = de->de_inode; 718 719 return (error); 720} 721 722/* ARGSUSED */ 723static int 724devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td) 725{ 726 struct cdev *dev; 727 struct cdevsw *dsw; 728 struct vnode *vp; 729 struct vnode *vpold; 730 int error, i, ref; 731 const char *p; 732 struct fiodgname_arg *fgn; 733 struct file *fpop; 734 735 fpop = td->td_fpop; 736 error = devfs_fp_check(fp, &dev, &dsw, &ref); 737 if (error != 0) { 738 error = vnops.fo_ioctl(fp, com, data, cred, td); 739 return (error); 740 } 741 742 if (com == FIODTYPE) { 743 *(int *)data = dsw->d_flags & D_TYPEMASK; 744 td->td_fpop = fpop; 745 dev_relthread(dev, ref); 746 return (0); 747 } else if (com == FIODGNAME) { 748 fgn = data; 749 p = devtoname(dev); 750 i = strlen(p) + 1; 751 if (i > fgn->len) 752 error = EINVAL; 753 else 754 error = copyout(p, fgn->buf, i); 755 td->td_fpop = fpop; 756 dev_relthread(dev, ref); 757 return (error); 758 } 759 error = dsw->d_ioctl(dev, com, data, fp->f_flag, td); 760 td->td_fpop = NULL; 761 dev_relthread(dev, ref); 762 if (error == ENOIOCTL) 763 error = ENOTTY; 764 if (error == 0 && com == TIOCSCTTY) { 765 vp = fp->f_vnode; 766 767 /* Do nothing if reassigning same control tty */ 768 sx_slock(&proctree_lock); 769 if (td->td_proc->p_session->s_ttyvp == vp) { 770 sx_sunlock(&proctree_lock); 771 return (0); 772 } 773 774 vpold = td->td_proc->p_session->s_ttyvp; 775 VREF(vp); 776 SESS_LOCK(td->td_proc->p_session); 777 td->td_proc->p_session->s_ttyvp = vp; 778 td->td_proc->p_session->s_ttydp = cdev2priv(dev); 779 SESS_UNLOCK(td->td_proc->p_session); 780 781 sx_sunlock(&proctree_lock); 782 783 /* Get rid of reference to old control tty */ 784 if (vpold) 785 vrele(vpold); 786 } 787 return (error); 788} 789 790/* ARGSUSED */ 791static int 792devfs_kqfilter_f(struct file *fp, struct knote *kn) 793{ 794 struct cdev *dev; 795 struct cdevsw *dsw; 796 int error, ref; 797 struct file *fpop; 798 struct thread *td; 799 800 td = curthread; 801 fpop = td->td_fpop; 802 error = devfs_fp_check(fp, &dev, &dsw, &ref); 803 if (error) 804 return (error); 805 error = dsw->d_kqfilter(dev, kn); 806 td->td_fpop = fpop; 807 dev_relthread(dev, ref); 808 return (error); 809} 810 811static inline int 812devfs_prison_check(struct devfs_dirent *de, struct thread *td) 813{ 814 struct cdev_priv *cdp; 815 struct ucred *dcr; 816 int error; 817 818 cdp = de->de_cdp; 819 if (cdp == NULL) 820 return (0); 821 dcr = cdp->cdp_c.si_cred; 822 if (dcr == NULL) 823 return (0); 824 825 error = prison_check(td->td_ucred, dcr); 826 if (error == 0) 827 return (0); 828 /* We do, however, allow access to the controlling terminal */ 829 if (!(td->td_proc->p_flag & P_CONTROLT)) 830 return (error); 831 if (td->td_proc->p_session->s_ttydp == cdp) 832 return (0); 833 return (error); 834} 835 836static int 837devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock) 838{ 839 struct componentname *cnp; 840 struct vnode *dvp, **vpp; 841 struct thread *td; 842 struct devfs_dirent *de, *dd; 843 struct devfs_dirent **dde; 844 struct devfs_mount *dmp; 845 struct cdev *cdev; 846 int error, flags, nameiop, dvplocked; 847 char specname[SPECNAMELEN + 1], *pname; 848 849 cnp = ap->a_cnp; 850 vpp = ap->a_vpp; 851 dvp = ap->a_dvp; 852 pname = cnp->cn_nameptr; 853 td = cnp->cn_thread; 854 flags = cnp->cn_flags; 855 nameiop = cnp->cn_nameiop; 856 dmp = VFSTODEVFS(dvp->v_mount); 857 dd = dvp->v_data; 858 *vpp = NULLVP; 859 860 if ((flags & ISLASTCN) && nameiop == RENAME) 861 return (EOPNOTSUPP); 862 863 if (dvp->v_type != VDIR) 864 return (ENOTDIR); 865 866 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT)) 867 return (EIO); 868 869 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td); 870 if (error) 871 return (error); 872 873 if (cnp->cn_namelen == 1 && *pname == '.') { 874 if ((flags & ISLASTCN) && nameiop != LOOKUP) 875 return (EINVAL); 876 *vpp = dvp; 877 VREF(dvp); 878 return (0); 879 } 880 881 if (flags & ISDOTDOT) { 882 if ((flags & ISLASTCN) && nameiop != LOOKUP) 883 return (EINVAL); 884 de = devfs_parent_dirent(dd); 885 if (de == NULL) 886 return (ENOENT); 887 dvplocked = VOP_ISLOCKED(dvp); 888 VOP_UNLOCK(dvp, 0); 889 error = devfs_allocv(de, dvp->v_mount, 890 cnp->cn_lkflags & LK_TYPE_MASK, vpp); 891 *dm_unlock = 0; 892 vn_lock(dvp, dvplocked | LK_RETRY); 893 return (error); 894 } 895 896 dd = dvp->v_data; 897 de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0); 898 while (de == NULL) { /* While(...) so we can use break */ 899 900 if (nameiop == DELETE) 901 return (ENOENT); 902 903 /* 904 * OK, we didn't have an entry for the name we were asked for 905 * so we try to see if anybody can create it on demand. 906 */ 907 pname = devfs_fqpn(specname, dmp, dd, cnp); 908 if (pname == NULL) 909 break; 910 911 cdev = NULL; 912 DEVFS_DMP_HOLD(dmp); 913 sx_xunlock(&dmp->dm_lock); 914 sx_slock(&clone_drain_lock); 915 EVENTHANDLER_INVOKE(dev_clone, 916 td->td_ucred, pname, strlen(pname), &cdev); 917 sx_sunlock(&clone_drain_lock); 918 919 if (cdev == NULL) 920 sx_xlock(&dmp->dm_lock); 921 else if (devfs_populate_vp(dvp) != 0) { 922 *dm_unlock = 0; 923 sx_xlock(&dmp->dm_lock); 924 if (DEVFS_DMP_DROP(dmp)) { 925 sx_xunlock(&dmp->dm_lock); 926 devfs_unmount_final(dmp); 927 } else 928 sx_xunlock(&dmp->dm_lock); 929 dev_rel(cdev); 930 return (ENOENT); 931 } 932 if (DEVFS_DMP_DROP(dmp)) { 933 *dm_unlock = 0; 934 sx_xunlock(&dmp->dm_lock); 935 devfs_unmount_final(dmp); 936 if (cdev != NULL) 937 dev_rel(cdev); 938 return (ENOENT); 939 } 940 941 if (cdev == NULL) 942 break; 943 944 dev_lock(); 945 dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx]; 946 if (dde != NULL && *dde != NULL) 947 de = *dde; 948 dev_unlock(); 949 dev_rel(cdev); 950 break; 951 } 952 953 if (de == NULL || de->de_flags & DE_WHITEOUT) { 954 if ((nameiop == CREATE || nameiop == RENAME) && 955 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) { 956 cnp->cn_flags |= SAVENAME; 957 return (EJUSTRETURN); 958 } 959 return (ENOENT); 960 } 961 962 if (devfs_prison_check(de, td)) 963 return (ENOENT); 964 965 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) { 966 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); 967 if (error) 968 return (error); 969 if (*vpp == dvp) { 970 VREF(dvp); 971 *vpp = dvp; 972 return (0); 973 } 974 } 975 error = devfs_allocv(de, dvp->v_mount, cnp->cn_lkflags & LK_TYPE_MASK, 976 vpp); 977 *dm_unlock = 0; 978 return (error); 979} 980 981static int 982devfs_lookup(struct vop_lookup_args *ap) 983{ 984 int j; 985 struct devfs_mount *dmp; 986 int dm_unlock; 987 988 if (devfs_populate_vp(ap->a_dvp) != 0) 989 return (ENOTDIR); 990 991 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 992 dm_unlock = 1; 993 j = devfs_lookupx(ap, &dm_unlock); 994 if (dm_unlock == 1) 995 sx_xunlock(&dmp->dm_lock); 996 return (j); 997} 998 999static int 1000devfs_mknod(struct vop_mknod_args *ap) 1001{ 1002 struct componentname *cnp; 1003 struct vnode *dvp, **vpp; 1004 struct devfs_dirent *dd, *de; 1005 struct devfs_mount *dmp; 1006 int error; 1007 1008 /* 1009 * The only type of node we should be creating here is a 1010 * character device, for anything else return EOPNOTSUPP. 1011 */ 1012 if (ap->a_vap->va_type != VCHR) 1013 return (EOPNOTSUPP); 1014 dvp = ap->a_dvp; 1015 dmp = VFSTODEVFS(dvp->v_mount); 1016 1017 cnp = ap->a_cnp; 1018 vpp = ap->a_vpp; 1019 dd = dvp->v_data; 1020 1021 error = ENOENT; 1022 sx_xlock(&dmp->dm_lock); 1023 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 1024 if (cnp->cn_namelen != de->de_dirent->d_namlen) 1025 continue; 1026 if (de->de_dirent->d_type == DT_CHR && 1027 (de->de_cdp->cdp_flags & CDP_ACTIVE) == 0) 1028 continue; 1029 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 1030 de->de_dirent->d_namlen) != 0) 1031 continue; 1032 if (de->de_flags & DE_WHITEOUT) 1033 break; 1034 goto notfound; 1035 } 1036 if (de == NULL) 1037 goto notfound; 1038 de->de_flags &= ~DE_WHITEOUT; 1039 error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp); 1040 return (error); 1041notfound: 1042 sx_xunlock(&dmp->dm_lock); 1043 return (error); 1044} 1045 1046/* ARGSUSED */ 1047static int 1048devfs_open(struct vop_open_args *ap) 1049{ 1050 struct thread *td = ap->a_td; 1051 struct vnode *vp = ap->a_vp; 1052 struct cdev *dev = vp->v_rdev; 1053 struct file *fp = ap->a_fp; 1054 int error, ref, vlocked; 1055 struct cdevsw *dsw; 1056 struct file *fpop; 1057 struct mtx *mtxp; 1058 1059 if (vp->v_type == VBLK) 1060 return (ENXIO); 1061 1062 if (dev == NULL) 1063 return (ENXIO); 1064 1065 /* Make this field valid before any I/O in d_open. */ 1066 if (dev->si_iosize_max == 0) 1067 dev->si_iosize_max = DFLTPHYS; 1068 1069 dsw = dev_refthread(dev, &ref); 1070 if (dsw == NULL) 1071 return (ENXIO); 1072 if (fp == NULL && dsw->d_fdopen != NULL) { 1073 dev_relthread(dev, ref); 1074 return (ENXIO); 1075 } 1076 1077 vlocked = VOP_ISLOCKED(vp); 1078 VOP_UNLOCK(vp, 0); 1079 1080 fpop = td->td_fpop; 1081 td->td_fpop = fp; 1082 if (fp != NULL) { 1083 fp->f_data = dev; 1084 fp->f_vnode = vp; 1085 } 1086 if (dsw->d_fdopen != NULL) 1087 error = dsw->d_fdopen(dev, ap->a_mode, td, fp); 1088 else 1089 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 1090 /* cleanup any cdevpriv upon error */ 1091 if (error != 0) 1092 devfs_clear_cdevpriv(); 1093 td->td_fpop = fpop; 1094 1095 vn_lock(vp, vlocked | LK_RETRY); 1096 dev_relthread(dev, ref); 1097 if (error != 0) { 1098 if (error == ERESTART) 1099 error = EINTR; 1100 return (error); 1101 } 1102 1103#if 0 /* /dev/console */ 1104 KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp")); 1105#else 1106 if (fp == NULL) 1107 return (error); 1108#endif 1109 if (fp->f_ops == &badfileops) 1110 finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f); 1111 mtxp = mtx_pool_find(mtxpool_sleep, fp); 1112 1113 /* 1114 * Hint to the dofilewrite() to not force the buffer draining 1115 * on the writer to the file. Most likely, the write would 1116 * not need normal buffers. 1117 */ 1118 mtx_lock(mtxp); 1119 fp->f_vnread_flags |= FDEVFS_VNODE; 1120 mtx_unlock(mtxp); 1121 return (error); 1122} 1123 1124static int 1125devfs_pathconf(struct vop_pathconf_args *ap) 1126{ 1127 1128 switch (ap->a_name) { 1129 case _PC_MAC_PRESENT: 1130#ifdef MAC 1131 /* 1132 * If MAC is enabled, devfs automatically supports 1133 * trivial non-persistant label storage. 1134 */ 1135 *ap->a_retval = 1; 1136#else 1137 *ap->a_retval = 0; 1138#endif 1139 return (0); 1140 default: 1141 return (vop_stdpathconf(ap)); 1142 } 1143 /* NOTREACHED */ 1144} 1145 1146/* ARGSUSED */ 1147static int 1148devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td) 1149{ 1150 struct cdev *dev; 1151 struct cdevsw *dsw; 1152 int error, ref; 1153 struct file *fpop; 1154 1155 fpop = td->td_fpop; 1156 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1157 if (error != 0) { 1158 error = vnops.fo_poll(fp, events, cred, td); 1159 return (error); 1160 } 1161 error = dsw->d_poll(dev, events, td); 1162 td->td_fpop = fpop; 1163 dev_relthread(dev, ref); 1164 return(error); 1165} 1166 1167/* 1168 * Print out the contents of a special device vnode. 1169 */ 1170static int 1171devfs_print(struct vop_print_args *ap) 1172{ 1173 1174 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev)); 1175 return (0); 1176} 1177 1178static int 1179devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred, 1180 int flags, struct thread *td) 1181{ 1182 struct cdev *dev; 1183 int ioflag, error, ref; 1184 ssize_t resid; 1185 struct cdevsw *dsw; 1186 struct file *fpop; 1187 1188 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1189 return (EINVAL); 1190 fpop = td->td_fpop; 1191 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1192 if (error != 0) { 1193 error = vnops.fo_read(fp, uio, cred, flags, td); 1194 return (error); 1195 } 1196 resid = uio->uio_resid; 1197 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT); 1198 if (ioflag & O_DIRECT) 1199 ioflag |= IO_DIRECT; 1200 1201 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1202 error = dsw->d_read(dev, uio, ioflag); 1203 if (uio->uio_resid != resid || (error == 0 && resid != 0)) 1204 vfs_timestamp(&dev->si_atime); 1205 td->td_fpop = fpop; 1206 dev_relthread(dev, ref); 1207 1208 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1209 return (error); 1210} 1211 1212static int 1213devfs_readdir(struct vop_readdir_args *ap) 1214{ 1215 int error; 1216 struct uio *uio; 1217 struct dirent *dp; 1218 struct devfs_dirent *dd; 1219 struct devfs_dirent *de; 1220 struct devfs_mount *dmp; 1221 off_t off; 1222 int *tmp_ncookies = NULL; 1223 1224 if (ap->a_vp->v_type != VDIR) 1225 return (ENOTDIR); 1226 1227 uio = ap->a_uio; 1228 if (uio->uio_offset < 0) 1229 return (EINVAL); 1230 1231 /* 1232 * XXX: This is a temporary hack to get around this filesystem not 1233 * supporting cookies. We store the location of the ncookies pointer 1234 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent() 1235 * and set the number of cookies to 0. We then set the pointer to 1236 * NULL so that vfs_read_dirent doesn't try to call realloc() on 1237 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies 1238 * pointer to its original location before returning to the caller. 1239 */ 1240 if (ap->a_ncookies != NULL) { 1241 tmp_ncookies = ap->a_ncookies; 1242 *ap->a_ncookies = 0; 1243 ap->a_ncookies = NULL; 1244 } 1245 1246 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1247 if (devfs_populate_vp(ap->a_vp) != 0) { 1248 if (tmp_ncookies != NULL) 1249 ap->a_ncookies = tmp_ncookies; 1250 return (EIO); 1251 } 1252 error = 0; 1253 de = ap->a_vp->v_data; 1254 off = 0; 1255 TAILQ_FOREACH(dd, &de->de_dlist, de_list) { 1256 KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__)); 1257 if (dd->de_flags & (DE_COVERED | DE_WHITEOUT)) 1258 continue; 1259 if (devfs_prison_check(dd, uio->uio_td)) 1260 continue; 1261 if (dd->de_dirent->d_type == DT_DIR) 1262 de = dd->de_dir; 1263 else 1264 de = dd; 1265 dp = dd->de_dirent; 1266 if (dp->d_reclen > uio->uio_resid) 1267 break; 1268 dp->d_fileno = de->de_inode; 1269 if (off >= uio->uio_offset) { 1270 error = vfs_read_dirent(ap, dp, off); 1271 if (error) 1272 break; 1273 } 1274 off += dp->d_reclen; 1275 } 1276 sx_xunlock(&dmp->dm_lock); 1277 uio->uio_offset = off; 1278 1279 /* 1280 * Restore ap->a_ncookies if it wasn't originally NULL in the first 1281 * place. 1282 */ 1283 if (tmp_ncookies != NULL) 1284 ap->a_ncookies = tmp_ncookies; 1285 1286 return (error); 1287} 1288 1289static int 1290devfs_readlink(struct vop_readlink_args *ap) 1291{ 1292 struct devfs_dirent *de; 1293 1294 de = ap->a_vp->v_data; 1295 return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio)); 1296} 1297 1298static int 1299devfs_reclaim(struct vop_reclaim_args *ap) 1300{ 1301 struct vnode *vp = ap->a_vp; 1302 struct devfs_dirent *de; 1303 struct cdev *dev; 1304 1305 mtx_lock(&devfs_de_interlock); 1306 de = vp->v_data; 1307 if (de != NULL) { 1308 de->de_vnode = NULL; 1309 vp->v_data = NULL; 1310 } 1311 mtx_unlock(&devfs_de_interlock); 1312 1313 vnode_destroy_vobject(vp); 1314 1315 VI_LOCK(vp); 1316 dev_lock(); 1317 dev = vp->v_rdev; 1318 vp->v_rdev = NULL; 1319 1320 if (dev == NULL) { 1321 dev_unlock(); 1322 VI_UNLOCK(vp); 1323 return (0); 1324 } 1325 1326 dev->si_usecount -= vp->v_usecount; 1327 dev_unlock(); 1328 VI_UNLOCK(vp); 1329 dev_rel(dev); 1330 return (0); 1331} 1332 1333static int 1334devfs_remove(struct vop_remove_args *ap) 1335{ 1336 struct vnode *dvp = ap->a_dvp; 1337 struct vnode *vp = ap->a_vp; 1338 struct devfs_dirent *dd; 1339 struct devfs_dirent *de, *de_covered; 1340 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); 1341 1342 ASSERT_VOP_ELOCKED(dvp, "devfs_remove"); 1343 ASSERT_VOP_ELOCKED(vp, "devfs_remove"); 1344 1345 sx_xlock(&dmp->dm_lock); 1346 dd = ap->a_dvp->v_data; 1347 de = vp->v_data; 1348 if (de->de_cdp == NULL) { 1349 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 1350 if (de->de_dirent->d_type == DT_LNK) { 1351 de_covered = devfs_find(dd, de->de_dirent->d_name, 1352 de->de_dirent->d_namlen, 0); 1353 if (de_covered != NULL) 1354 de_covered->de_flags &= ~DE_COVERED; 1355 } 1356 /* We need to unlock dvp because devfs_delete() may lock it. */ 1357 VOP_UNLOCK(vp, 0); 1358 if (dvp != vp) 1359 VOP_UNLOCK(dvp, 0); 1360 devfs_delete(dmp, de, 0); 1361 sx_xunlock(&dmp->dm_lock); 1362 if (dvp != vp) 1363 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1364 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1365 } else { 1366 de->de_flags |= DE_WHITEOUT; 1367 sx_xunlock(&dmp->dm_lock); 1368 } 1369 return (0); 1370} 1371 1372/* 1373 * Revoke is called on a tty when a terminal session ends. The vnode 1374 * is orphaned by setting v_op to deadfs so we need to let go of it 1375 * as well so that we create a new one next time around. 1376 * 1377 */ 1378static int 1379devfs_revoke(struct vop_revoke_args *ap) 1380{ 1381 struct vnode *vp = ap->a_vp, *vp2; 1382 struct cdev *dev; 1383 struct cdev_priv *cdp; 1384 struct devfs_dirent *de; 1385 int i; 1386 1387 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL")); 1388 1389 dev = vp->v_rdev; 1390 cdp = cdev2priv(dev); 1391 1392 dev_lock(); 1393 cdp->cdp_inuse++; 1394 dev_unlock(); 1395 1396 vhold(vp); 1397 vgone(vp); 1398 vdrop(vp); 1399 1400 VOP_UNLOCK(vp,0); 1401 loop: 1402 for (;;) { 1403 mtx_lock(&devfs_de_interlock); 1404 dev_lock(); 1405 vp2 = NULL; 1406 for (i = 0; i <= cdp->cdp_maxdirent; i++) { 1407 de = cdp->cdp_dirents[i]; 1408 if (de == NULL) 1409 continue; 1410 1411 vp2 = de->de_vnode; 1412 if (vp2 != NULL) { 1413 dev_unlock(); 1414 VI_LOCK(vp2); 1415 mtx_unlock(&devfs_de_interlock); 1416 if (vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK, 1417 curthread)) 1418 goto loop; 1419 vhold(vp2); 1420 vgone(vp2); 1421 vdrop(vp2); 1422 vput(vp2); 1423 break; 1424 } 1425 } 1426 if (vp2 != NULL) { 1427 continue; 1428 } 1429 dev_unlock(); 1430 mtx_unlock(&devfs_de_interlock); 1431 break; 1432 } 1433 dev_lock(); 1434 cdp->cdp_inuse--; 1435 if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) { 1436 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); 1437 dev_unlock(); 1438 dev_rel(&cdp->cdp_c); 1439 } else 1440 dev_unlock(); 1441 1442 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1443 return (0); 1444} 1445 1446static int 1447devfs_rioctl(struct vop_ioctl_args *ap) 1448{ 1449 struct vnode *vp; 1450 struct devfs_mount *dmp; 1451 int error; 1452 1453 vp = ap->a_vp; 1454 vn_lock(vp, LK_SHARED | LK_RETRY); 1455 if (vp->v_iflag & VI_DOOMED) { 1456 VOP_UNLOCK(vp, 0); 1457 return (EBADF); 1458 } 1459 dmp = VFSTODEVFS(vp->v_mount); 1460 sx_xlock(&dmp->dm_lock); 1461 VOP_UNLOCK(vp, 0); 1462 DEVFS_DMP_HOLD(dmp); 1463 devfs_populate(dmp); 1464 if (DEVFS_DMP_DROP(dmp)) { 1465 sx_xunlock(&dmp->dm_lock); 1466 devfs_unmount_final(dmp); 1467 return (ENOENT); 1468 } 1469 error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td); 1470 sx_xunlock(&dmp->dm_lock); 1471 return (error); 1472} 1473 1474static int 1475devfs_rread(struct vop_read_args *ap) 1476{ 1477 1478 if (ap->a_vp->v_type != VDIR) 1479 return (EINVAL); 1480 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL)); 1481} 1482 1483static int 1484devfs_setattr(struct vop_setattr_args *ap) 1485{ 1486 struct devfs_dirent *de; 1487 struct vattr *vap; 1488 struct vnode *vp; 1489 struct thread *td; 1490 int c, error; 1491 uid_t uid; 1492 gid_t gid; 1493 1494 vap = ap->a_vap; 1495 vp = ap->a_vp; 1496 td = curthread; 1497 if ((vap->va_type != VNON) || 1498 (vap->va_nlink != VNOVAL) || 1499 (vap->va_fsid != VNOVAL) || 1500 (vap->va_fileid != VNOVAL) || 1501 (vap->va_blocksize != VNOVAL) || 1502 (vap->va_flags != VNOVAL && vap->va_flags != 0) || 1503 (vap->va_rdev != VNOVAL) || 1504 ((int)vap->va_bytes != VNOVAL) || 1505 (vap->va_gen != VNOVAL)) { 1506 return (EINVAL); 1507 } 1508 1509 de = vp->v_data; 1510 if (vp->v_type == VDIR) 1511 de = de->de_dir; 1512 1513 error = c = 0; 1514 if (vap->va_uid == (uid_t)VNOVAL) 1515 uid = de->de_uid; 1516 else 1517 uid = vap->va_uid; 1518 if (vap->va_gid == (gid_t)VNOVAL) 1519 gid = de->de_gid; 1520 else 1521 gid = vap->va_gid; 1522 if (uid != de->de_uid || gid != de->de_gid) { 1523 if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid || 1524 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) { 1525 error = priv_check(td, PRIV_VFS_CHOWN); 1526 if (error) 1527 return (error); 1528 } 1529 de->de_uid = uid; 1530 de->de_gid = gid; 1531 c = 1; 1532 } 1533 1534 if (vap->va_mode != (mode_t)VNOVAL) { 1535 if (ap->a_cred->cr_uid != de->de_uid) { 1536 error = priv_check(td, PRIV_VFS_ADMIN); 1537 if (error) 1538 return (error); 1539 } 1540 de->de_mode = vap->va_mode; 1541 c = 1; 1542 } 1543 1544 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 1545 error = vn_utimes_perm(vp, vap, ap->a_cred, td); 1546 if (error != 0) 1547 return (error); 1548 if (vap->va_atime.tv_sec != VNOVAL) { 1549 if (vp->v_type == VCHR) 1550 vp->v_rdev->si_atime = vap->va_atime; 1551 else 1552 de->de_atime = vap->va_atime; 1553 } 1554 if (vap->va_mtime.tv_sec != VNOVAL) { 1555 if (vp->v_type == VCHR) 1556 vp->v_rdev->si_mtime = vap->va_mtime; 1557 else 1558 de->de_mtime = vap->va_mtime; 1559 } 1560 c = 1; 1561 } 1562 1563 if (c) { 1564 if (vp->v_type == VCHR) 1565 vfs_timestamp(&vp->v_rdev->si_ctime); 1566 else 1567 vfs_timestamp(&de->de_mtime); 1568 } 1569 return (0); 1570} 1571 1572#ifdef MAC 1573static int 1574devfs_setlabel(struct vop_setlabel_args *ap) 1575{ 1576 struct vnode *vp; 1577 struct devfs_dirent *de; 1578 1579 vp = ap->a_vp; 1580 de = vp->v_data; 1581 1582 mac_vnode_relabel(ap->a_cred, vp, ap->a_label); 1583 mac_devfs_update(vp->v_mount, de, vp); 1584 1585 return (0); 1586} 1587#endif 1588 1589static int 1590devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td) 1591{ 1592 1593 return (vnops.fo_stat(fp, sb, cred, td)); 1594} 1595 1596static int 1597devfs_symlink(struct vop_symlink_args *ap) 1598{ 1599 int i, error; 1600 struct devfs_dirent *dd; 1601 struct devfs_dirent *de, *de_covered, *de_dotdot; 1602 struct devfs_mount *dmp; 1603 1604 error = priv_check(curthread, PRIV_DEVFS_SYMLINK); 1605 if (error) 1606 return(error); 1607 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1608 if (devfs_populate_vp(ap->a_dvp) != 0) 1609 return (ENOENT); 1610 1611 dd = ap->a_dvp->v_data; 1612 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen); 1613 de->de_flags = DE_USER; 1614 de->de_uid = 0; 1615 de->de_gid = 0; 1616 de->de_mode = 0755; 1617 de->de_inode = alloc_unr(devfs_inos); 1618 de->de_dir = dd; 1619 de->de_dirent->d_type = DT_LNK; 1620 i = strlen(ap->a_target) + 1; 1621 de->de_symlink = malloc(i, M_DEVFS, M_WAITOK); 1622 bcopy(ap->a_target, de->de_symlink, i); 1623#ifdef MAC 1624 mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de); 1625#endif 1626 de_covered = devfs_find(dd, de->de_dirent->d_name, 1627 de->de_dirent->d_namlen, 0); 1628 if (de_covered != NULL) { 1629 if ((de_covered->de_flags & DE_USER) != 0) { 1630 devfs_delete(dmp, de, DEVFS_DEL_NORECURSE); 1631 sx_xunlock(&dmp->dm_lock); 1632 return (EEXIST); 1633 } 1634 KASSERT((de_covered->de_flags & DE_COVERED) == 0, 1635 ("devfs_symlink: entry %p already covered", de_covered)); 1636 de_covered->de_flags |= DE_COVERED; 1637 } 1638 1639 de_dotdot = TAILQ_FIRST(&dd->de_dlist); /* "." */ 1640 de_dotdot = TAILQ_NEXT(de_dotdot, de_list); /* ".." */ 1641 TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list); 1642 devfs_dir_ref_de(dmp, dd); 1643 devfs_rules_apply(dmp, de); 1644 1645 return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp)); 1646} 1647 1648static int 1649devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td) 1650{ 1651 1652 return (vnops.fo_truncate(fp, length, cred, td)); 1653} 1654 1655static int 1656devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred, 1657 int flags, struct thread *td) 1658{ 1659 struct cdev *dev; 1660 int error, ioflag, ref; 1661 ssize_t resid; 1662 struct cdevsw *dsw; 1663 struct file *fpop; 1664 1665 if (uio->uio_resid > DEVFS_IOSIZE_MAX) 1666 return (EINVAL); 1667 fpop = td->td_fpop; 1668 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1669 if (error != 0) { 1670 error = vnops.fo_write(fp, uio, cred, flags, td); 1671 return (error); 1672 } 1673 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td)); 1674 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC); 1675 if (ioflag & O_DIRECT) 1676 ioflag |= IO_DIRECT; 1677 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1678 1679 resid = uio->uio_resid; 1680 1681 error = dsw->d_write(dev, uio, ioflag); 1682 if (uio->uio_resid != resid || (error == 0 && resid != 0)) { 1683 vfs_timestamp(&dev->si_ctime); 1684 dev->si_mtime = dev->si_ctime; 1685 } 1686 td->td_fpop = fpop; 1687 dev_relthread(dev, ref); 1688 1689 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1690 return (error); 1691} 1692 1693dev_t 1694dev2udev(struct cdev *x) 1695{ 1696 if (x == NULL) 1697 return (NODEV); 1698 return (cdev2priv(x)->cdp_inode); 1699} 1700 1701static struct fileops devfs_ops_f = { 1702 .fo_read = devfs_read_f, 1703 .fo_write = devfs_write_f, 1704 .fo_truncate = devfs_truncate_f, 1705 .fo_ioctl = devfs_ioctl_f, 1706 .fo_poll = devfs_poll_f, 1707 .fo_kqfilter = devfs_kqfilter_f, 1708 .fo_stat = devfs_stat_f, 1709 .fo_close = devfs_close_f, 1710 .fo_chmod = vn_chmod, 1711 .fo_chown = vn_chown, 1712 .fo_sendfile = vn_sendfile, 1713 .fo_seek = vn_seek, 1714 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE 1715}; 1716 1717static struct vop_vector devfs_vnodeops = { 1718 .vop_default = &default_vnodeops, 1719 1720 .vop_access = devfs_access, 1721 .vop_getattr = devfs_getattr, 1722 .vop_ioctl = devfs_rioctl, 1723 .vop_lookup = devfs_lookup, 1724 .vop_mknod = devfs_mknod, 1725 .vop_pathconf = devfs_pathconf, 1726 .vop_read = devfs_rread, 1727 .vop_readdir = devfs_readdir, 1728 .vop_readlink = devfs_readlink, 1729 .vop_reclaim = devfs_reclaim, 1730 .vop_remove = devfs_remove, 1731 .vop_revoke = devfs_revoke, 1732 .vop_setattr = devfs_setattr, 1733#ifdef MAC 1734 .vop_setlabel = devfs_setlabel, 1735#endif 1736 .vop_symlink = devfs_symlink, 1737 .vop_vptocnp = devfs_vptocnp, 1738}; 1739 1740static struct vop_vector devfs_specops = { 1741 .vop_default = &default_vnodeops, 1742 1743 .vop_access = devfs_access, 1744 .vop_bmap = VOP_PANIC, 1745 .vop_close = devfs_close, 1746 .vop_create = VOP_PANIC, 1747 .vop_fsync = devfs_fsync, 1748 .vop_getattr = devfs_getattr, 1749 .vop_link = VOP_PANIC, 1750 .vop_mkdir = VOP_PANIC, 1751 .vop_mknod = VOP_PANIC, 1752 .vop_open = devfs_open, 1753 .vop_pathconf = devfs_pathconf, 1754 .vop_poll = dead_poll, 1755 .vop_print = devfs_print, 1756 .vop_read = dead_read, 1757 .vop_readdir = VOP_PANIC, 1758 .vop_readlink = VOP_PANIC, 1759 .vop_reallocblks = VOP_PANIC, 1760 .vop_reclaim = devfs_reclaim, 1761 .vop_remove = devfs_remove, 1762 .vop_rename = VOP_PANIC, 1763 .vop_revoke = devfs_revoke, 1764 .vop_rmdir = VOP_PANIC, 1765 .vop_setattr = devfs_setattr, 1766#ifdef MAC 1767 .vop_setlabel = devfs_setlabel, 1768#endif 1769 .vop_strategy = VOP_PANIC, 1770 .vop_symlink = VOP_PANIC, 1771 .vop_vptocnp = devfs_vptocnp, 1772 .vop_write = dead_write, 1773}; 1774 1775/* 1776 * Our calling convention to the device drivers used to be that we passed 1777 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_ 1778 * flags instead since that's what open(), close() and ioctl() takes and 1779 * we don't really want vnode.h in device drivers. 1780 * We solved the source compatibility by redefining some vnode flags to 1781 * be the same as the fcntl ones and by sending down the bitwise OR of 1782 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody 1783 * pulls the rug out under this. 1784 */ 1785CTASSERT(O_NONBLOCK == IO_NDELAY); 1786CTASSERT(O_FSYNC == IO_SYNC); 1787