devfs_vnops.c revision 257121
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 257121 2013-10-25 16:31:28Z 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) 738 return (error); 739 740 if (com == FIODTYPE) { 741 *(int *)data = dsw->d_flags & D_TYPEMASK; 742 td->td_fpop = fpop; 743 dev_relthread(dev, ref); 744 return (0); 745 } else if (com == FIODGNAME) { 746 fgn = data; 747 p = devtoname(dev); 748 i = strlen(p) + 1; 749 if (i > fgn->len) 750 error = EINVAL; 751 else 752 error = copyout(p, fgn->buf, i); 753 td->td_fpop = fpop; 754 dev_relthread(dev, ref); 755 return (error); 756 } 757 error = dsw->d_ioctl(dev, com, data, fp->f_flag, td); 758 td->td_fpop = NULL; 759 dev_relthread(dev, ref); 760 if (error == ENOIOCTL) 761 error = ENOTTY; 762 if (error == 0 && com == TIOCSCTTY) { 763 vp = fp->f_vnode; 764 765 /* Do nothing if reassigning same control tty */ 766 sx_slock(&proctree_lock); 767 if (td->td_proc->p_session->s_ttyvp == vp) { 768 sx_sunlock(&proctree_lock); 769 return (0); 770 } 771 772 vpold = td->td_proc->p_session->s_ttyvp; 773 VREF(vp); 774 SESS_LOCK(td->td_proc->p_session); 775 td->td_proc->p_session->s_ttyvp = vp; 776 td->td_proc->p_session->s_ttydp = cdev2priv(dev); 777 SESS_UNLOCK(td->td_proc->p_session); 778 779 sx_sunlock(&proctree_lock); 780 781 /* Get rid of reference to old control tty */ 782 if (vpold) 783 vrele(vpold); 784 } 785 return (error); 786} 787 788/* ARGSUSED */ 789static int 790devfs_kqfilter_f(struct file *fp, struct knote *kn) 791{ 792 struct cdev *dev; 793 struct cdevsw *dsw; 794 int error, ref; 795 struct file *fpop; 796 struct thread *td; 797 798 td = curthread; 799 fpop = td->td_fpop; 800 error = devfs_fp_check(fp, &dev, &dsw, &ref); 801 if (error) 802 return (error); 803 error = dsw->d_kqfilter(dev, kn); 804 td->td_fpop = fpop; 805 dev_relthread(dev, ref); 806 return (error); 807} 808 809static inline int 810devfs_prison_check(struct devfs_dirent *de, struct thread *td) 811{ 812 struct cdev_priv *cdp; 813 struct ucred *dcr; 814 int error; 815 816 cdp = de->de_cdp; 817 if (cdp == NULL) 818 return (0); 819 dcr = cdp->cdp_c.si_cred; 820 if (dcr == NULL) 821 return (0); 822 823 error = prison_check(td->td_ucred, dcr); 824 if (error == 0) 825 return (0); 826 /* We do, however, allow access to the controlling terminal */ 827 if (!(td->td_proc->p_flag & P_CONTROLT)) 828 return (error); 829 if (td->td_proc->p_session->s_ttydp == cdp) 830 return (0); 831 return (error); 832} 833 834static int 835devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock) 836{ 837 struct componentname *cnp; 838 struct vnode *dvp, **vpp; 839 struct thread *td; 840 struct devfs_dirent *de, *dd; 841 struct devfs_dirent **dde; 842 struct devfs_mount *dmp; 843 struct cdev *cdev; 844 int error, flags, nameiop, dvplocked; 845 char specname[SPECNAMELEN + 1], *pname; 846 847 cnp = ap->a_cnp; 848 vpp = ap->a_vpp; 849 dvp = ap->a_dvp; 850 pname = cnp->cn_nameptr; 851 td = cnp->cn_thread; 852 flags = cnp->cn_flags; 853 nameiop = cnp->cn_nameiop; 854 dmp = VFSTODEVFS(dvp->v_mount); 855 dd = dvp->v_data; 856 *vpp = NULLVP; 857 858 if ((flags & ISLASTCN) && nameiop == RENAME) 859 return (EOPNOTSUPP); 860 861 if (dvp->v_type != VDIR) 862 return (ENOTDIR); 863 864 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT)) 865 return (EIO); 866 867 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td); 868 if (error) 869 return (error); 870 871 if (cnp->cn_namelen == 1 && *pname == '.') { 872 if ((flags & ISLASTCN) && nameiop != LOOKUP) 873 return (EINVAL); 874 *vpp = dvp; 875 VREF(dvp); 876 return (0); 877 } 878 879 if (flags & ISDOTDOT) { 880 if ((flags & ISLASTCN) && nameiop != LOOKUP) 881 return (EINVAL); 882 de = devfs_parent_dirent(dd); 883 if (de == NULL) 884 return (ENOENT); 885 dvplocked = VOP_ISLOCKED(dvp); 886 VOP_UNLOCK(dvp, 0); 887 error = devfs_allocv(de, dvp->v_mount, 888 cnp->cn_lkflags & LK_TYPE_MASK, vpp); 889 *dm_unlock = 0; 890 vn_lock(dvp, dvplocked | LK_RETRY); 891 return (error); 892 } 893 894 dd = dvp->v_data; 895 de = devfs_find(dd, cnp->cn_nameptr, cnp->cn_namelen, 0); 896 while (de == NULL) { /* While(...) so we can use break */ 897 898 if (nameiop == DELETE) 899 return (ENOENT); 900 901 /* 902 * OK, we didn't have an entry for the name we were asked for 903 * so we try to see if anybody can create it on demand. 904 */ 905 pname = devfs_fqpn(specname, dmp, dd, cnp); 906 if (pname == NULL) 907 break; 908 909 cdev = NULL; 910 DEVFS_DMP_HOLD(dmp); 911 sx_xunlock(&dmp->dm_lock); 912 sx_slock(&clone_drain_lock); 913 EVENTHANDLER_INVOKE(dev_clone, 914 td->td_ucred, pname, strlen(pname), &cdev); 915 sx_sunlock(&clone_drain_lock); 916 917 if (cdev == NULL) 918 sx_xlock(&dmp->dm_lock); 919 else if (devfs_populate_vp(dvp) != 0) { 920 *dm_unlock = 0; 921 sx_xlock(&dmp->dm_lock); 922 if (DEVFS_DMP_DROP(dmp)) { 923 sx_xunlock(&dmp->dm_lock); 924 devfs_unmount_final(dmp); 925 } else 926 sx_xunlock(&dmp->dm_lock); 927 dev_rel(cdev); 928 return (ENOENT); 929 } 930 if (DEVFS_DMP_DROP(dmp)) { 931 *dm_unlock = 0; 932 sx_xunlock(&dmp->dm_lock); 933 devfs_unmount_final(dmp); 934 if (cdev != NULL) 935 dev_rel(cdev); 936 return (ENOENT); 937 } 938 939 if (cdev == NULL) 940 break; 941 942 dev_lock(); 943 dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx]; 944 if (dde != NULL && *dde != NULL) 945 de = *dde; 946 dev_unlock(); 947 dev_rel(cdev); 948 break; 949 } 950 951 if (de == NULL || de->de_flags & DE_WHITEOUT) { 952 if ((nameiop == CREATE || nameiop == RENAME) && 953 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) { 954 cnp->cn_flags |= SAVENAME; 955 return (EJUSTRETURN); 956 } 957 return (ENOENT); 958 } 959 960 if (devfs_prison_check(de, td)) 961 return (ENOENT); 962 963 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) { 964 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); 965 if (error) 966 return (error); 967 if (*vpp == dvp) { 968 VREF(dvp); 969 *vpp = dvp; 970 return (0); 971 } 972 } 973 error = devfs_allocv(de, dvp->v_mount, cnp->cn_lkflags & LK_TYPE_MASK, 974 vpp); 975 *dm_unlock = 0; 976 return (error); 977} 978 979static int 980devfs_lookup(struct vop_lookup_args *ap) 981{ 982 int j; 983 struct devfs_mount *dmp; 984 int dm_unlock; 985 986 if (devfs_populate_vp(ap->a_dvp) != 0) 987 return (ENOTDIR); 988 989 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 990 dm_unlock = 1; 991 j = devfs_lookupx(ap, &dm_unlock); 992 if (dm_unlock == 1) 993 sx_xunlock(&dmp->dm_lock); 994 return (j); 995} 996 997static int 998devfs_mknod(struct vop_mknod_args *ap) 999{ 1000 struct componentname *cnp; 1001 struct vnode *dvp, **vpp; 1002 struct devfs_dirent *dd, *de; 1003 struct devfs_mount *dmp; 1004 int error; 1005 1006 /* 1007 * The only type of node we should be creating here is a 1008 * character device, for anything else return EOPNOTSUPP. 1009 */ 1010 if (ap->a_vap->va_type != VCHR) 1011 return (EOPNOTSUPP); 1012 dvp = ap->a_dvp; 1013 dmp = VFSTODEVFS(dvp->v_mount); 1014 1015 cnp = ap->a_cnp; 1016 vpp = ap->a_vpp; 1017 dd = dvp->v_data; 1018 1019 error = ENOENT; 1020 sx_xlock(&dmp->dm_lock); 1021 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 1022 if (cnp->cn_namelen != de->de_dirent->d_namlen) 1023 continue; 1024 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 1025 de->de_dirent->d_namlen) != 0) 1026 continue; 1027 if (de->de_flags & DE_WHITEOUT) 1028 break; 1029 goto notfound; 1030 } 1031 if (de == NULL) 1032 goto notfound; 1033 de->de_flags &= ~DE_WHITEOUT; 1034 error = devfs_allocv(de, dvp->v_mount, LK_EXCLUSIVE, vpp); 1035 return (error); 1036notfound: 1037 sx_xunlock(&dmp->dm_lock); 1038 return (error); 1039} 1040 1041/* ARGSUSED */ 1042static int 1043devfs_open(struct vop_open_args *ap) 1044{ 1045 struct thread *td = ap->a_td; 1046 struct vnode *vp = ap->a_vp; 1047 struct cdev *dev = vp->v_rdev; 1048 struct file *fp = ap->a_fp; 1049 int error, ref, vlocked; 1050 struct cdevsw *dsw; 1051 struct file *fpop; 1052 struct mtx *mtxp; 1053 1054 if (vp->v_type == VBLK) 1055 return (ENXIO); 1056 1057 if (dev == NULL) 1058 return (ENXIO); 1059 1060 /* Make this field valid before any I/O in d_open. */ 1061 if (dev->si_iosize_max == 0) 1062 dev->si_iosize_max = DFLTPHYS; 1063 1064 dsw = dev_refthread(dev, &ref); 1065 if (dsw == NULL) 1066 return (ENXIO); 1067 if (fp == NULL && dsw->d_fdopen != NULL) { 1068 dev_relthread(dev, ref); 1069 return (ENXIO); 1070 } 1071 1072 vlocked = VOP_ISLOCKED(vp); 1073 VOP_UNLOCK(vp, 0); 1074 1075 fpop = td->td_fpop; 1076 td->td_fpop = fp; 1077 if (fp != NULL) { 1078 fp->f_data = dev; 1079 fp->f_vnode = vp; 1080 } 1081 if (dsw->d_fdopen != NULL) 1082 error = dsw->d_fdopen(dev, ap->a_mode, td, fp); 1083 else 1084 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 1085 /* cleanup any cdevpriv upon error */ 1086 if (error != 0) 1087 devfs_clear_cdevpriv(); 1088 td->td_fpop = fpop; 1089 1090 vn_lock(vp, vlocked | LK_RETRY); 1091 dev_relthread(dev, ref); 1092 if (error != 0) { 1093 if (error == ERESTART) 1094 error = EINTR; 1095 return (error); 1096 } 1097 1098#if 0 /* /dev/console */ 1099 KASSERT(fp != NULL, ("Could not vnode bypass device on NULL fp")); 1100#else 1101 if (fp == NULL) 1102 return (error); 1103#endif 1104 if (fp->f_ops == &badfileops) 1105 finit(fp, fp->f_flag, DTYPE_VNODE, dev, &devfs_ops_f); 1106 mtxp = mtx_pool_find(mtxpool_sleep, fp); 1107 1108 /* 1109 * Hint to the dofilewrite() to not force the buffer draining 1110 * on the writer to the file. Most likely, the write would 1111 * not need normal buffers. 1112 */ 1113 mtx_lock(mtxp); 1114 fp->f_vnread_flags |= FDEVFS_VNODE; 1115 mtx_unlock(mtxp); 1116 return (error); 1117} 1118 1119static int 1120devfs_pathconf(struct vop_pathconf_args *ap) 1121{ 1122 1123 switch (ap->a_name) { 1124 case _PC_MAC_PRESENT: 1125#ifdef MAC 1126 /* 1127 * If MAC is enabled, devfs automatically supports 1128 * trivial non-persistant label storage. 1129 */ 1130 *ap->a_retval = 1; 1131#else 1132 *ap->a_retval = 0; 1133#endif 1134 return (0); 1135 default: 1136 return (vop_stdpathconf(ap)); 1137 } 1138 /* NOTREACHED */ 1139} 1140 1141/* ARGSUSED */ 1142static int 1143devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td) 1144{ 1145 struct cdev *dev; 1146 struct cdevsw *dsw; 1147 int error, ref; 1148 struct file *fpop; 1149 1150 fpop = td->td_fpop; 1151 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1152 if (error) 1153 return (poll_no_poll(events)); 1154 error = dsw->d_poll(dev, events, td); 1155 td->td_fpop = fpop; 1156 dev_relthread(dev, ref); 1157 return(error); 1158} 1159 1160/* 1161 * Print out the contents of a special device vnode. 1162 */ 1163static int 1164devfs_print(struct vop_print_args *ap) 1165{ 1166 1167 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev)); 1168 return (0); 1169} 1170 1171static int 1172devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred, 1173 int flags, struct thread *td) 1174{ 1175 struct cdev *dev; 1176 int ioflag, error, ref; 1177 ssize_t resid; 1178 struct cdevsw *dsw; 1179 struct file *fpop; 1180 1181 fpop = td->td_fpop; 1182 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1183 if (error) 1184 return (error); 1185 resid = uio->uio_resid; 1186 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT); 1187 if (ioflag & O_DIRECT) 1188 ioflag |= IO_DIRECT; 1189 1190 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1191 error = dsw->d_read(dev, uio, ioflag); 1192 if (uio->uio_resid != resid || (error == 0 && resid != 0)) 1193 vfs_timestamp(&dev->si_atime); 1194 td->td_fpop = fpop; 1195 dev_relthread(dev, ref); 1196 1197 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1198 return (error); 1199} 1200 1201static int 1202devfs_readdir(struct vop_readdir_args *ap) 1203{ 1204 int error; 1205 struct uio *uio; 1206 struct dirent *dp; 1207 struct devfs_dirent *dd; 1208 struct devfs_dirent *de; 1209 struct devfs_mount *dmp; 1210 off_t off; 1211 int *tmp_ncookies = NULL; 1212 1213 if (ap->a_vp->v_type != VDIR) 1214 return (ENOTDIR); 1215 1216 uio = ap->a_uio; 1217 if (uio->uio_offset < 0) 1218 return (EINVAL); 1219 1220 /* 1221 * XXX: This is a temporary hack to get around this filesystem not 1222 * supporting cookies. We store the location of the ncookies pointer 1223 * in a temporary variable before calling vfs_subr.c:vfs_read_dirent() 1224 * and set the number of cookies to 0. We then set the pointer to 1225 * NULL so that vfs_read_dirent doesn't try to call realloc() on 1226 * ap->a_cookies. Later in this function, we restore the ap->a_ncookies 1227 * pointer to its original location before returning to the caller. 1228 */ 1229 if (ap->a_ncookies != NULL) { 1230 tmp_ncookies = ap->a_ncookies; 1231 *ap->a_ncookies = 0; 1232 ap->a_ncookies = NULL; 1233 } 1234 1235 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1236 if (devfs_populate_vp(ap->a_vp) != 0) { 1237 if (tmp_ncookies != NULL) 1238 ap->a_ncookies = tmp_ncookies; 1239 return (EIO); 1240 } 1241 error = 0; 1242 de = ap->a_vp->v_data; 1243 off = 0; 1244 TAILQ_FOREACH(dd, &de->de_dlist, de_list) { 1245 KASSERT(dd->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__)); 1246 if (dd->de_flags & (DE_COVERED | DE_WHITEOUT)) 1247 continue; 1248 if (devfs_prison_check(dd, uio->uio_td)) 1249 continue; 1250 if (dd->de_dirent->d_type == DT_DIR) 1251 de = dd->de_dir; 1252 else 1253 de = dd; 1254 dp = dd->de_dirent; 1255 if (dp->d_reclen > uio->uio_resid) 1256 break; 1257 dp->d_fileno = de->de_inode; 1258 if (off >= uio->uio_offset) { 1259 error = vfs_read_dirent(ap, dp, off); 1260 if (error) 1261 break; 1262 } 1263 off += dp->d_reclen; 1264 } 1265 sx_xunlock(&dmp->dm_lock); 1266 uio->uio_offset = off; 1267 1268 /* 1269 * Restore ap->a_ncookies if it wasn't originally NULL in the first 1270 * place. 1271 */ 1272 if (tmp_ncookies != NULL) 1273 ap->a_ncookies = tmp_ncookies; 1274 1275 return (error); 1276} 1277 1278static int 1279devfs_readlink(struct vop_readlink_args *ap) 1280{ 1281 struct devfs_dirent *de; 1282 1283 de = ap->a_vp->v_data; 1284 return (uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio)); 1285} 1286 1287static int 1288devfs_reclaim(struct vop_reclaim_args *ap) 1289{ 1290 struct vnode *vp = ap->a_vp; 1291 struct devfs_dirent *de; 1292 struct cdev *dev; 1293 1294 mtx_lock(&devfs_de_interlock); 1295 de = vp->v_data; 1296 if (de != NULL) { 1297 de->de_vnode = NULL; 1298 vp->v_data = NULL; 1299 } 1300 mtx_unlock(&devfs_de_interlock); 1301 1302 vnode_destroy_vobject(vp); 1303 1304 VI_LOCK(vp); 1305 dev_lock(); 1306 dev = vp->v_rdev; 1307 vp->v_rdev = NULL; 1308 1309 if (dev == NULL) { 1310 dev_unlock(); 1311 VI_UNLOCK(vp); 1312 return (0); 1313 } 1314 1315 dev->si_usecount -= vp->v_usecount; 1316 dev_unlock(); 1317 VI_UNLOCK(vp); 1318 dev_rel(dev); 1319 return (0); 1320} 1321 1322static int 1323devfs_remove(struct vop_remove_args *ap) 1324{ 1325 struct vnode *dvp = ap->a_dvp; 1326 struct vnode *vp = ap->a_vp; 1327 struct devfs_dirent *dd; 1328 struct devfs_dirent *de, *de_covered; 1329 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); 1330 1331 ASSERT_VOP_ELOCKED(dvp, "devfs_remove"); 1332 ASSERT_VOP_ELOCKED(vp, "devfs_remove"); 1333 1334 sx_xlock(&dmp->dm_lock); 1335 dd = ap->a_dvp->v_data; 1336 de = vp->v_data; 1337 if (de->de_cdp == NULL) { 1338 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 1339 if (de->de_dirent->d_type == DT_LNK) { 1340 de_covered = devfs_find(dd, de->de_dirent->d_name, 1341 de->de_dirent->d_namlen, 0); 1342 if (de_covered != NULL) 1343 de_covered->de_flags &= ~DE_COVERED; 1344 } 1345 /* We need to unlock dvp because devfs_delete() may lock it. */ 1346 VOP_UNLOCK(vp, 0); 1347 if (dvp != vp) 1348 VOP_UNLOCK(dvp, 0); 1349 devfs_delete(dmp, de, 0); 1350 sx_xunlock(&dmp->dm_lock); 1351 if (dvp != vp) 1352 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1353 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1354 } else { 1355 de->de_flags |= DE_WHITEOUT; 1356 sx_xunlock(&dmp->dm_lock); 1357 } 1358 return (0); 1359} 1360 1361/* 1362 * Revoke is called on a tty when a terminal session ends. The vnode 1363 * is orphaned by setting v_op to deadfs so we need to let go of it 1364 * as well so that we create a new one next time around. 1365 * 1366 */ 1367static int 1368devfs_revoke(struct vop_revoke_args *ap) 1369{ 1370 struct vnode *vp = ap->a_vp, *vp2; 1371 struct cdev *dev; 1372 struct cdev_priv *cdp; 1373 struct devfs_dirent *de; 1374 int i; 1375 1376 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL")); 1377 1378 dev = vp->v_rdev; 1379 cdp = cdev2priv(dev); 1380 1381 dev_lock(); 1382 cdp->cdp_inuse++; 1383 dev_unlock(); 1384 1385 vhold(vp); 1386 vgone(vp); 1387 vdrop(vp); 1388 1389 VOP_UNLOCK(vp,0); 1390 loop: 1391 for (;;) { 1392 mtx_lock(&devfs_de_interlock); 1393 dev_lock(); 1394 vp2 = NULL; 1395 for (i = 0; i <= cdp->cdp_maxdirent; i++) { 1396 de = cdp->cdp_dirents[i]; 1397 if (de == NULL) 1398 continue; 1399 1400 vp2 = de->de_vnode; 1401 if (vp2 != NULL) { 1402 dev_unlock(); 1403 VI_LOCK(vp2); 1404 mtx_unlock(&devfs_de_interlock); 1405 if (vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK, 1406 curthread)) 1407 goto loop; 1408 vhold(vp2); 1409 vgone(vp2); 1410 vdrop(vp2); 1411 vput(vp2); 1412 break; 1413 } 1414 } 1415 if (vp2 != NULL) { 1416 continue; 1417 } 1418 dev_unlock(); 1419 mtx_unlock(&devfs_de_interlock); 1420 break; 1421 } 1422 dev_lock(); 1423 cdp->cdp_inuse--; 1424 if (!(cdp->cdp_flags & CDP_ACTIVE) && cdp->cdp_inuse == 0) { 1425 TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); 1426 dev_unlock(); 1427 dev_rel(&cdp->cdp_c); 1428 } else 1429 dev_unlock(); 1430 1431 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1432 return (0); 1433} 1434 1435static int 1436devfs_rioctl(struct vop_ioctl_args *ap) 1437{ 1438 struct vnode *vp; 1439 struct devfs_mount *dmp; 1440 int error; 1441 1442 vp = ap->a_vp; 1443 vn_lock(vp, LK_SHARED | LK_RETRY); 1444 if (vp->v_iflag & VI_DOOMED) { 1445 VOP_UNLOCK(vp, 0); 1446 return (EBADF); 1447 } 1448 dmp = VFSTODEVFS(vp->v_mount); 1449 sx_xlock(&dmp->dm_lock); 1450 VOP_UNLOCK(vp, 0); 1451 DEVFS_DMP_HOLD(dmp); 1452 devfs_populate(dmp); 1453 if (DEVFS_DMP_DROP(dmp)) { 1454 sx_xunlock(&dmp->dm_lock); 1455 devfs_unmount_final(dmp); 1456 return (ENOENT); 1457 } 1458 error = devfs_rules_ioctl(dmp, ap->a_command, ap->a_data, ap->a_td); 1459 sx_xunlock(&dmp->dm_lock); 1460 return (error); 1461} 1462 1463static int 1464devfs_rread(struct vop_read_args *ap) 1465{ 1466 1467 if (ap->a_vp->v_type != VDIR) 1468 return (EINVAL); 1469 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL)); 1470} 1471 1472static int 1473devfs_setattr(struct vop_setattr_args *ap) 1474{ 1475 struct devfs_dirent *de; 1476 struct vattr *vap; 1477 struct vnode *vp; 1478 struct thread *td; 1479 int c, error; 1480 uid_t uid; 1481 gid_t gid; 1482 1483 vap = ap->a_vap; 1484 vp = ap->a_vp; 1485 td = curthread; 1486 if ((vap->va_type != VNON) || 1487 (vap->va_nlink != VNOVAL) || 1488 (vap->va_fsid != VNOVAL) || 1489 (vap->va_fileid != VNOVAL) || 1490 (vap->va_blocksize != VNOVAL) || 1491 (vap->va_flags != VNOVAL && vap->va_flags != 0) || 1492 (vap->va_rdev != VNOVAL) || 1493 ((int)vap->va_bytes != VNOVAL) || 1494 (vap->va_gen != VNOVAL)) { 1495 return (EINVAL); 1496 } 1497 1498 de = vp->v_data; 1499 if (vp->v_type == VDIR) 1500 de = de->de_dir; 1501 1502 error = c = 0; 1503 if (vap->va_uid == (uid_t)VNOVAL) 1504 uid = de->de_uid; 1505 else 1506 uid = vap->va_uid; 1507 if (vap->va_gid == (gid_t)VNOVAL) 1508 gid = de->de_gid; 1509 else 1510 gid = vap->va_gid; 1511 if (uid != de->de_uid || gid != de->de_gid) { 1512 if ((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid || 1513 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) { 1514 error = priv_check(td, PRIV_VFS_CHOWN); 1515 if (error) 1516 return (error); 1517 } 1518 de->de_uid = uid; 1519 de->de_gid = gid; 1520 c = 1; 1521 } 1522 1523 if (vap->va_mode != (mode_t)VNOVAL) { 1524 if (ap->a_cred->cr_uid != de->de_uid) { 1525 error = priv_check(td, PRIV_VFS_ADMIN); 1526 if (error) 1527 return (error); 1528 } 1529 de->de_mode = vap->va_mode; 1530 c = 1; 1531 } 1532 1533 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 1534 /* See the comment in ufs_vnops::ufs_setattr(). */ 1535 if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, td)) && 1536 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 1537 (error = VOP_ACCESS(vp, VWRITE, ap->a_cred, td)))) 1538 return (error); 1539 if (vap->va_atime.tv_sec != VNOVAL) { 1540 if (vp->v_type == VCHR) 1541 vp->v_rdev->si_atime = vap->va_atime; 1542 else 1543 de->de_atime = vap->va_atime; 1544 } 1545 if (vap->va_mtime.tv_sec != VNOVAL) { 1546 if (vp->v_type == VCHR) 1547 vp->v_rdev->si_mtime = vap->va_mtime; 1548 else 1549 de->de_mtime = vap->va_mtime; 1550 } 1551 c = 1; 1552 } 1553 1554 if (c) { 1555 if (vp->v_type == VCHR) 1556 vfs_timestamp(&vp->v_rdev->si_ctime); 1557 else 1558 vfs_timestamp(&de->de_mtime); 1559 } 1560 return (0); 1561} 1562 1563#ifdef MAC 1564static int 1565devfs_setlabel(struct vop_setlabel_args *ap) 1566{ 1567 struct vnode *vp; 1568 struct devfs_dirent *de; 1569 1570 vp = ap->a_vp; 1571 de = vp->v_data; 1572 1573 mac_vnode_relabel(ap->a_cred, vp, ap->a_label); 1574 mac_devfs_update(vp->v_mount, de, vp); 1575 1576 return (0); 1577} 1578#endif 1579 1580static int 1581devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td) 1582{ 1583 1584 return (vnops.fo_stat(fp, sb, cred, td)); 1585} 1586 1587static int 1588devfs_symlink(struct vop_symlink_args *ap) 1589{ 1590 int i, error; 1591 struct devfs_dirent *dd; 1592 struct devfs_dirent *de, *de_covered, *de_dotdot; 1593 struct devfs_mount *dmp; 1594 1595 error = priv_check(curthread, PRIV_DEVFS_SYMLINK); 1596 if (error) 1597 return(error); 1598 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1599 if (devfs_populate_vp(ap->a_dvp) != 0) 1600 return (ENOENT); 1601 1602 dd = ap->a_dvp->v_data; 1603 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen); 1604 de->de_flags = DE_USER; 1605 de->de_uid = 0; 1606 de->de_gid = 0; 1607 de->de_mode = 0755; 1608 de->de_inode = alloc_unr(devfs_inos); 1609 de->de_dir = dd; 1610 de->de_dirent->d_type = DT_LNK; 1611 i = strlen(ap->a_target) + 1; 1612 de->de_symlink = malloc(i, M_DEVFS, M_WAITOK); 1613 bcopy(ap->a_target, de->de_symlink, i); 1614#ifdef MAC 1615 mac_devfs_create_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de); 1616#endif 1617 de_covered = devfs_find(dd, de->de_dirent->d_name, 1618 de->de_dirent->d_namlen, 0); 1619 if (de_covered != NULL) { 1620 if ((de_covered->de_flags & DE_USER) != 0) { 1621 devfs_delete(dmp, de, DEVFS_DEL_NORECURSE); 1622 sx_xunlock(&dmp->dm_lock); 1623 return (EEXIST); 1624 } 1625 KASSERT((de_covered->de_flags & DE_COVERED) == 0, 1626 ("devfs_symlink: entry %p already covered", de_covered)); 1627 de_covered->de_flags |= DE_COVERED; 1628 } 1629 1630 de_dotdot = TAILQ_FIRST(&dd->de_dlist); /* "." */ 1631 de_dotdot = TAILQ_NEXT(de_dotdot, de_list); /* ".." */ 1632 TAILQ_INSERT_AFTER(&dd->de_dlist, de_dotdot, de, de_list); 1633 devfs_dir_ref_de(dmp, dd); 1634 devfs_rules_apply(dmp, de); 1635 1636 return (devfs_allocv(de, ap->a_dvp->v_mount, LK_EXCLUSIVE, ap->a_vpp)); 1637} 1638 1639static int 1640devfs_truncate_f(struct file *fp, off_t length, struct ucred *cred, struct thread *td) 1641{ 1642 1643 return (vnops.fo_truncate(fp, length, cred, td)); 1644} 1645 1646static int 1647devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred, 1648 int flags, struct thread *td) 1649{ 1650 struct cdev *dev; 1651 int error, ioflag, ref; 1652 ssize_t resid; 1653 struct cdevsw *dsw; 1654 struct file *fpop; 1655 1656 fpop = td->td_fpop; 1657 error = devfs_fp_check(fp, &dev, &dsw, &ref); 1658 if (error) 1659 return (error); 1660 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td)); 1661 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC); 1662 if (ioflag & O_DIRECT) 1663 ioflag |= IO_DIRECT; 1664 foffset_lock_uio(fp, uio, flags | FOF_NOLOCK); 1665 1666 resid = uio->uio_resid; 1667 1668 error = dsw->d_write(dev, uio, ioflag); 1669 if (uio->uio_resid != resid || (error == 0 && resid != 0)) { 1670 vfs_timestamp(&dev->si_ctime); 1671 dev->si_mtime = dev->si_ctime; 1672 } 1673 td->td_fpop = fpop; 1674 dev_relthread(dev, ref); 1675 1676 foffset_unlock_uio(fp, uio, flags | FOF_NOLOCK | FOF_NEXTOFF); 1677 return (error); 1678} 1679 1680dev_t 1681dev2udev(struct cdev *x) 1682{ 1683 if (x == NULL) 1684 return (NODEV); 1685 return (cdev2priv(x)->cdp_inode); 1686} 1687 1688static struct fileops devfs_ops_f = { 1689 .fo_read = devfs_read_f, 1690 .fo_write = devfs_write_f, 1691 .fo_truncate = devfs_truncate_f, 1692 .fo_ioctl = devfs_ioctl_f, 1693 .fo_poll = devfs_poll_f, 1694 .fo_kqfilter = devfs_kqfilter_f, 1695 .fo_stat = devfs_stat_f, 1696 .fo_close = devfs_close_f, 1697 .fo_chmod = vn_chmod, 1698 .fo_chown = vn_chown, 1699 .fo_sendfile = vn_sendfile, 1700 .fo_seek = vn_seek, 1701 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE 1702}; 1703 1704static struct vop_vector devfs_vnodeops = { 1705 .vop_default = &default_vnodeops, 1706 1707 .vop_access = devfs_access, 1708 .vop_getattr = devfs_getattr, 1709 .vop_ioctl = devfs_rioctl, 1710 .vop_lookup = devfs_lookup, 1711 .vop_mknod = devfs_mknod, 1712 .vop_pathconf = devfs_pathconf, 1713 .vop_read = devfs_rread, 1714 .vop_readdir = devfs_readdir, 1715 .vop_readlink = devfs_readlink, 1716 .vop_reclaim = devfs_reclaim, 1717 .vop_remove = devfs_remove, 1718 .vop_revoke = devfs_revoke, 1719 .vop_setattr = devfs_setattr, 1720#ifdef MAC 1721 .vop_setlabel = devfs_setlabel, 1722#endif 1723 .vop_symlink = devfs_symlink, 1724 .vop_vptocnp = devfs_vptocnp, 1725}; 1726 1727static struct vop_vector devfs_specops = { 1728 .vop_default = &default_vnodeops, 1729 1730 .vop_access = devfs_access, 1731 .vop_bmap = VOP_PANIC, 1732 .vop_close = devfs_close, 1733 .vop_create = VOP_PANIC, 1734 .vop_fsync = devfs_fsync, 1735 .vop_getattr = devfs_getattr, 1736 .vop_link = VOP_PANIC, 1737 .vop_mkdir = VOP_PANIC, 1738 .vop_mknod = VOP_PANIC, 1739 .vop_open = devfs_open, 1740 .vop_pathconf = devfs_pathconf, 1741 .vop_print = devfs_print, 1742 .vop_read = VOP_PANIC, 1743 .vop_readdir = VOP_PANIC, 1744 .vop_readlink = VOP_PANIC, 1745 .vop_reallocblks = VOP_PANIC, 1746 .vop_reclaim = devfs_reclaim, 1747 .vop_remove = devfs_remove, 1748 .vop_rename = VOP_PANIC, 1749 .vop_revoke = devfs_revoke, 1750 .vop_rmdir = VOP_PANIC, 1751 .vop_setattr = devfs_setattr, 1752#ifdef MAC 1753 .vop_setlabel = devfs_setlabel, 1754#endif 1755 .vop_strategy = VOP_PANIC, 1756 .vop_symlink = VOP_PANIC, 1757 .vop_vptocnp = devfs_vptocnp, 1758 .vop_write = VOP_PANIC, 1759}; 1760 1761/* 1762 * Our calling convention to the device drivers used to be that we passed 1763 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_ 1764 * flags instead since that's what open(), close() and ioctl() takes and 1765 * we don't really want vnode.h in device drivers. 1766 * We solved the source compatibility by redefining some vnode flags to 1767 * be the same as the fcntl ones and by sending down the bitwise OR of 1768 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody 1769 * pulls the rug out under this. 1770 */ 1771CTASSERT(O_NONBLOCK == IO_NDELAY); 1772CTASSERT(O_FSYNC == IO_SYNC); 1773