1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 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. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94 39 * $Id: vfs_subr.c,v 1.43 1995/11/20 12:42:11 phk Exp $ 40 */ 41 42 /* 43 * External virtual filesystem routines 44 */ 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/file.h> 50 #include <sys/proc.h> 51 #include <sys/mount.h> 52 #include <sys/time.h> 53 #include <sys/vnode.h> 54 #include <sys/stat.h> 55 #include <sys/namei.h> 56 #include <sys/ucred.h> 57 #include <sys/buf.h> 58 #include <sys/errno.h> 59 #include <sys/malloc.h> 60 #include <sys/domain.h> 61 #include <sys/mbuf.h> 62 63 #include <vm/vm.h> 64 #include <sys/sysctl.h> 65 66 #include <miscfs/specfs/specdev.h> 67 68 enum vtype iftovt_tab[16] = { 69 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 70 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 71 }; 72 int vttoif_tab[9] = { 73 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 74 S_IFSOCK, S_IFIFO, S_IFMT, 75 }; 76 77 /* 78 * Insq/Remq for the vnode usage lists. 79 */ 80 #define bufinsvn(bp, dp) LIST_INSERT_HEAD(dp, bp, b_vnbufs) 81 #define bufremvn(bp) { \ 82 LIST_REMOVE(bp, b_vnbufs); \ 83 (bp)->b_vnbufs.le_next = NOLIST; \ 84 } 85 86 TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ 87 u_long freevnodes = 0; 88 89 struct mntlist mountlist; /* mounted filesystem list */ 90 91 int desiredvnodes; 92 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RD, &desiredvnodes, 0, ""); 93 94 /* 95 * Initialize the vnode management data structures. 96 */ 97 void 98 vntblinit() 99 { 100 desiredvnodes = maxproc + vm_object_cache_max; 101 102 TAILQ_INIT(&vnode_free_list); 103 CIRCLEQ_INIT(&mountlist); 104 } 105 106 /* 107 * Lock a filesystem. 108 * Used to prevent access to it while mounting and unmounting. 109 */ 110 int 111 vfs_lock(mp) 112 register struct mount *mp; 113 { 114 115 while (mp->mnt_flag & MNT_MLOCK) { 116 mp->mnt_flag |= MNT_MWAIT; 117 (void) tsleep((caddr_t) mp, PVFS, "vfslck", 0); 118 } 119 mp->mnt_flag |= MNT_MLOCK; 120 return (0); 121 } 122 123 /* 124 * Unlock a locked filesystem. 125 * Panic if filesystem is not locked. 126 */ 127 void 128 vfs_unlock(mp) 129 register struct mount *mp; 130 { 131 132 if ((mp->mnt_flag & MNT_MLOCK) == 0) 133 panic("vfs_unlock: not locked"); 134 mp->mnt_flag &= ~MNT_MLOCK; 135 if (mp->mnt_flag & MNT_MWAIT) { 136 mp->mnt_flag &= ~MNT_MWAIT; 137 wakeup((caddr_t) mp); 138 } 139 } 140 141 /* 142 * Mark a mount point as busy. 143 * Used to synchronize access and to delay unmounting. 144 */ 145 int 146 vfs_busy(mp) 147 register struct mount *mp; 148 { 149 150 while (mp->mnt_flag & MNT_MPBUSY) { 151 mp->mnt_flag |= MNT_MPWANT; 152 (void) tsleep((caddr_t) &mp->mnt_flag, PVFS, "vfsbsy", 0); 153 } 154 if (mp->mnt_flag & MNT_UNMOUNT) 155 return (1); 156 mp->mnt_flag |= MNT_MPBUSY; 157 return (0); 158 } 159 160 /* 161 * Free a busy filesystem. 162 * Panic if filesystem is not busy. 163 */ 164 void 165 vfs_unbusy(mp) 166 register struct mount *mp; 167 { 168 169 if ((mp->mnt_flag & MNT_MPBUSY) == 0) 170 panic("vfs_unbusy: not busy"); 171 mp->mnt_flag &= ~MNT_MPBUSY; 172 if (mp->mnt_flag & MNT_MPWANT) { 173 mp->mnt_flag &= ~MNT_MPWANT; 174 wakeup((caddr_t) &mp->mnt_flag); 175 } 176 } 177 178 void 179 vfs_unmountroot(struct mount *rootfs) 180 { 181 struct mount *mp = rootfs; 182 int error; 183 184 if (vfs_busy(mp)) { 185 printf("failed to unmount root\n"); 186 return; 187 } 188 mp->mnt_flag |= MNT_UNMOUNT; 189 if ((error = vfs_lock(mp))) { 190 printf("lock of root filesystem failed (%d)\n", error); 191 return; 192 } 193 vnode_pager_umount(mp); /* release cached vnodes */ 194 cache_purgevfs(mp); /* remove cache entries for this file sys */ 195 196 if ((error = VFS_SYNC(mp, MNT_WAIT, initproc->p_ucred, initproc))) 197 printf("sync of root filesystem failed (%d)\n", error); 198 199 if ((error = VFS_UNMOUNT(mp, MNT_FORCE, initproc))) { 200 printf("unmount of root filesystem failed ("); 201 if (error == EBUSY) 202 printf("BUSY)\n"); 203 else 204 printf("%d)\n", error); 205 } 206 mp->mnt_flag &= ~MNT_UNMOUNT; 207 vfs_unbusy(mp); 208 } 209 210 /* 211 * Unmount all filesystems. Should only be called by halt(). 212 */ 213 void 214 vfs_unmountall() 215 { 216 struct mount *mp, *nmp, *rootfs = NULL; 217 int error; 218 219 /* unmount all but rootfs */ 220 for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) { 221 nmp = mp->mnt_list.cqe_prev; 222 223 if (mp->mnt_flag & MNT_ROOTFS) { 224 rootfs = mp; 225 continue; 226 } 227 error = dounmount(mp, MNT_FORCE, initproc); 228 if (error) { 229 printf("unmount of %s failed (", mp->mnt_stat.f_mntonname); 230 if (error == EBUSY) 231 printf("BUSY)\n"); 232 else 233 printf("%d)\n", error); 234 } 235 } 236 237 /* and finally... */ 238 if (rootfs) { 239 vfs_unmountroot(rootfs); 240 } else { 241 printf("no root filesystem\n"); 242 } 243 } 244 245 /* 246 * Lookup a mount point by filesystem identifier. 247 */ 248 struct mount * 249 getvfs(fsid) 250 fsid_t *fsid; 251 { 252 register struct mount *mp; 253 254 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; 255 mp = mp->mnt_list.cqe_next) { 256 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 257 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) 258 return (mp); 259 } 260 return ((struct mount *) 0); 261 } 262 263 /* 264 * Get a new unique fsid 265 */ 266 void 267 getnewfsid(mp, mtype) 268 struct mount *mp; 269 int mtype; 270 { 271 static u_short xxxfs_mntid; 272 273 fsid_t tfsid; 274 275 mp->mnt_stat.f_fsid.val[0] = makedev(nblkdev + mtype, 0); 276 mp->mnt_stat.f_fsid.val[1] = mtype; 277 if (xxxfs_mntid == 0) 278 ++xxxfs_mntid; 279 tfsid.val[0] = makedev(nblkdev + mtype, xxxfs_mntid); 280 tfsid.val[1] = mtype; 281 if (mountlist.cqh_first != (void *)&mountlist) { 282 while (getvfs(&tfsid)) { 283 tfsid.val[0]++; 284 xxxfs_mntid++; 285 } 286 } 287 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 288 } 289 290 /* 291 * Set vnode attributes to VNOVAL 292 */ 293 void 294 vattr_null(vap) 295 register struct vattr *vap; 296 { 297 298 vap->va_type = VNON; 299 vap->va_size = VNOVAL; 300 vap->va_bytes = VNOVAL; 301 vap->va_mode = vap->va_nlink = vap->va_uid = vap->va_gid = 302 vap->va_fsid = vap->va_fileid = 303 vap->va_blocksize = vap->va_rdev = 304 vap->va_atime.ts_sec = vap->va_atime.ts_nsec = 305 vap->va_mtime.ts_sec = vap->va_mtime.ts_nsec = 306 vap->va_ctime.ts_sec = vap->va_ctime.ts_nsec = 307 vap->va_flags = vap->va_gen = VNOVAL; 308 vap->va_vaflags = 0; 309 } 310 311 /* 312 * Routines having to do with the management of the vnode table. 313 */ 314 extern vop_t **dead_vnodeop_p; 315 extern void vclean(); 316 317 /* 318 * Return the next vnode from the free list. 319 */ 320 int 321 getnewvnode(tag, mp, vops, vpp) 322 enum vtagtype tag; 323 struct mount *mp; 324 vop_t **vops; 325 struct vnode **vpp; 326 { 327 register struct vnode *vp; 328 329 vp = vnode_free_list.tqh_first; 330 /* 331 * we allocate a new vnode if 332 * 1. we don't have any free 333 * Pretty obvious, we actually used to panic, but that 334 * is a silly thing to do. 335 * 2. we havn't filled our pool yet 336 * We don't want to trash the incore (VM-)vnodecache. 337 * 3. if less that 1/4th of our vnodes are free. 338 * We don't want to trash the namei cache either. 339 */ 340 if (freevnodes < (numvnodes >> 2) || 341 numvnodes < desiredvnodes || 342 vp == NULL) { 343 vp = (struct vnode *) malloc((u_long) sizeof *vp, 344 M_VNODE, M_WAITOK); 345 bzero((char *) vp, sizeof *vp); 346 numvnodes++; 347 } else { 348 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 349 freevnodes--; 350 351 if (vp->v_usecount) 352 panic("free vnode isn't"); 353 354 /* see comment on why 0xdeadb is set at end of vgone (below) */ 355 vp->v_freelist.tqe_prev = (struct vnode **) 0xdeadb; 356 vp->v_lease = NULL; 357 if (vp->v_type != VBAD) 358 vgone(vp); 359 #ifdef DIAGNOSTIC 360 { 361 int s; 362 363 if (vp->v_data) 364 panic("cleaned vnode isn't"); 365 s = splbio(); 366 if (vp->v_numoutput) 367 panic("Clean vnode has pending I/O's"); 368 splx(s); 369 } 370 #endif 371 vp->v_flag = 0; 372 vp->v_lastr = 0; 373 vp->v_ralen = 0; 374 vp->v_maxra = 0; 375 vp->v_lastw = 0; 376 vp->v_lasta = 0; 377 vp->v_cstart = 0; 378 vp->v_clen = 0; 379 vp->v_socket = 0; 380 vp->v_writecount = 0; /* XXX */ 381 } 382 vp->v_type = VNON; 383 cache_purge(vp); 384 vp->v_tag = tag; 385 vp->v_op = vops; 386 insmntque(vp, mp); 387 *vpp = vp; 388 vp->v_usecount = 1; 389 vp->v_data = 0; 390 return (0); 391 } 392 393 /* 394 * Move a vnode from one mount queue to another. 395 */ 396 void 397 insmntque(vp, mp) 398 register struct vnode *vp; 399 register struct mount *mp; 400 { 401 402 /* 403 * Delete from old mount point vnode list, if on one. 404 */ 405 if (vp->v_mount != NULL) 406 LIST_REMOVE(vp, v_mntvnodes); 407 /* 408 * Insert into list of vnodes for the new mount point, if available. 409 */ 410 if ((vp->v_mount = mp) == NULL) 411 return; 412 LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); 413 } 414 415 /* 416 * Update outstanding I/O count and do wakeup if requested. 417 */ 418 void 419 vwakeup(bp) 420 register struct buf *bp; 421 { 422 register struct vnode *vp; 423 424 bp->b_flags &= ~B_WRITEINPROG; 425 if ((vp = bp->b_vp)) { 426 vp->v_numoutput--; 427 if (vp->v_numoutput < 0) 428 panic("vwakeup: neg numoutput"); 429 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { 430 vp->v_flag &= ~VBWAIT; 431 wakeup((caddr_t) &vp->v_numoutput); 432 } 433 } 434 } 435 436 /* 437 * Flush out and invalidate all buffers associated with a vnode. 438 * Called with the underlying object locked. 439 */ 440 int 441 vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) 442 register struct vnode *vp; 443 int flags; 444 struct ucred *cred; 445 struct proc *p; 446 int slpflag, slptimeo; 447 { 448 register struct buf *bp; 449 struct buf *nbp, *blist; 450 int s, error; 451 vm_object_t object; 452 453 if (flags & V_SAVE) { 454 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p))) 455 return (error); 456 if (vp->v_dirtyblkhd.lh_first != NULL) 457 panic("vinvalbuf: dirty bufs"); 458 } 459 for (;;) { 460 if ((blist = vp->v_cleanblkhd.lh_first) && (flags & V_SAVEMETA)) 461 while (blist && blist->b_lblkno < 0) 462 blist = blist->b_vnbufs.le_next; 463 if (!blist && (blist = vp->v_dirtyblkhd.lh_first) && 464 (flags & V_SAVEMETA)) 465 while (blist && blist->b_lblkno < 0) 466 blist = blist->b_vnbufs.le_next; 467 if (!blist) 468 break; 469 470 for (bp = blist; bp; bp = nbp) { 471 nbp = bp->b_vnbufs.le_next; 472 if ((flags & V_SAVEMETA) && bp->b_lblkno < 0) 473 continue; 474 s = splbio(); 475 if (bp->b_flags & B_BUSY) { 476 bp->b_flags |= B_WANTED; 477 error = tsleep((caddr_t) bp, 478 slpflag | (PRIBIO + 1), "vinvalbuf", 479 slptimeo); 480 splx(s); 481 if (error) 482 return (error); 483 break; 484 } 485 bremfree(bp); 486 bp->b_flags |= B_BUSY; 487 splx(s); 488 /* 489 * XXX Since there are no node locks for NFS, I 490 * believe there is a slight chance that a delayed 491 * write will occur while sleeping just above, so 492 * check for it. 493 */ 494 if ((bp->b_flags & B_DELWRI) && (flags & V_SAVE)) { 495 (void) VOP_BWRITE(bp); 496 break; 497 } 498 bp->b_flags |= (B_INVAL|B_NOCACHE|B_RELBUF); 499 brelse(bp); 500 } 501 } 502 503 s = splbio(); 504 while (vp->v_numoutput > 0) { 505 vp->v_flag |= VBWAIT; 506 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 507 } 508 splx(s); 509 510 /* 511 * Destroy the copy in the VM cache, too. 512 */ 513 object = vp->v_object; 514 if (object != NULL) { 515 vm_object_page_remove(object, 0, object->size, 516 (flags & V_SAVE) ? TRUE : FALSE); 517 } 518 if (!(flags & V_SAVEMETA) && 519 (vp->v_dirtyblkhd.lh_first || vp->v_cleanblkhd.lh_first)) 520 panic("vinvalbuf: flush failed"); 521 return (0); 522 } 523 524 /* 525 * Associate a buffer with a vnode. 526 */ 527 void 528 bgetvp(vp, bp) 529 register struct vnode *vp; 530 register struct buf *bp; 531 { 532 int s; 533 534 if (bp->b_vp) 535 panic("bgetvp: not free"); 536 VHOLD(vp); 537 bp->b_vp = vp; 538 if (vp->v_type == VBLK || vp->v_type == VCHR) 539 bp->b_dev = vp->v_rdev; 540 else 541 bp->b_dev = NODEV; 542 /* 543 * Insert onto list for new vnode. 544 */ 545 s = splbio(); 546 bufinsvn(bp, &vp->v_cleanblkhd); 547 splx(s); 548 } 549 550 /* 551 * Disassociate a buffer from a vnode. 552 */ 553 void 554 brelvp(bp) 555 register struct buf *bp; 556 { 557 struct vnode *vp; 558 int s; 559 560 if (bp->b_vp == (struct vnode *) 0) 561 panic("brelvp: NULL"); 562 /* 563 * Delete from old vnode list, if on one. 564 */ 565 s = splbio(); 566 if (bp->b_vnbufs.le_next != NOLIST) 567 bufremvn(bp); 568 splx(s); 569 570 vp = bp->b_vp; 571 bp->b_vp = (struct vnode *) 0; 572 HOLDRELE(vp); 573 } 574 575 /* 576 * Associate a p-buffer with a vnode. 577 */ 578 void 579 pbgetvp(vp, bp) 580 register struct vnode *vp; 581 register struct buf *bp; 582 { 583 if (bp->b_vp) 584 panic("pbgetvp: not free"); 585 VHOLD(vp); 586 bp->b_vp = vp; 587 if (vp->v_type == VBLK || vp->v_type == VCHR) 588 bp->b_dev = vp->v_rdev; 589 else 590 bp->b_dev = NODEV; 591 } 592 593 /* 594 * Disassociate a p-buffer from a vnode. 595 */ 596 void 597 pbrelvp(bp) 598 register struct buf *bp; 599 { 600 struct vnode *vp; 601 602 if (bp->b_vp == (struct vnode *) 0) 603 panic("brelvp: NULL"); 604 605 vp = bp->b_vp; 606 bp->b_vp = (struct vnode *) 0; 607 HOLDRELE(vp); 608 } 609 610 /* 611 * Reassign a buffer from one vnode to another. 612 * Used to assign file specific control information 613 * (indirect blocks) to the vnode to which they belong. 614 */ 615 void 616 reassignbuf(bp, newvp) 617 register struct buf *bp; 618 register struct vnode *newvp; 619 { 620 register struct buflists *listheadp; 621 622 if (newvp == NULL) { 623 printf("reassignbuf: NULL"); 624 return; 625 } 626 /* 627 * Delete from old vnode list, if on one. 628 */ 629 if (bp->b_vnbufs.le_next != NOLIST) 630 bufremvn(bp); 631 /* 632 * If dirty, put on list of dirty buffers; otherwise insert onto list 633 * of clean buffers. 634 */ 635 if (bp->b_flags & B_DELWRI) { 636 struct buf *tbp; 637 638 tbp = newvp->v_dirtyblkhd.lh_first; 639 if (!tbp || (tbp->b_lblkno > bp->b_lblkno)) { 640 bufinsvn(bp, &newvp->v_dirtyblkhd); 641 } else { 642 while (tbp->b_vnbufs.le_next && (tbp->b_vnbufs.le_next->b_lblkno < bp->b_lblkno)) { 643 tbp = tbp->b_vnbufs.le_next; 644 } 645 LIST_INSERT_AFTER(tbp, bp, b_vnbufs); 646 } 647 } else { 648 listheadp = &newvp->v_cleanblkhd; 649 bufinsvn(bp, listheadp); 650 } 651 } 652 653 /* 654 * Create a vnode for a block device. 655 * Used for root filesystem, argdev, and swap areas. 656 * Also used for memory file system special devices. 657 */ 658 int 659 bdevvp(dev, vpp) 660 dev_t dev; 661 struct vnode **vpp; 662 { 663 register struct vnode *vp; 664 struct vnode *nvp; 665 int error; 666 667 if (dev == NODEV) 668 return (0); 669 error = getnewvnode(VT_NON, (struct mount *) 0, spec_vnodeop_p, &nvp); 670 if (error) { 671 *vpp = 0; 672 return (error); 673 } 674 vp = nvp; 675 vp->v_type = VBLK; 676 if ((nvp = checkalias(vp, dev, (struct mount *) 0))) { 677 vput(vp); 678 vp = nvp; 679 } 680 *vpp = vp; 681 return (0); 682 } 683 684 /* 685 * Check to see if the new vnode represents a special device 686 * for which we already have a vnode (either because of 687 * bdevvp() or because of a different vnode representing 688 * the same block device). If such an alias exists, deallocate 689 * the existing contents and return the aliased vnode. The 690 * caller is responsible for filling it with its new contents. 691 */ 692 struct vnode * 693 checkalias(nvp, nvp_rdev, mp) 694 register struct vnode *nvp; 695 dev_t nvp_rdev; 696 struct mount *mp; 697 { 698 register struct vnode *vp; 699 struct vnode **vpp; 700 701 if (nvp->v_type != VBLK && nvp->v_type != VCHR) 702 return (NULLVP); 703 704 vpp = &speclisth[SPECHASH(nvp_rdev)]; 705 loop: 706 for (vp = *vpp; vp; vp = vp->v_specnext) { 707 if (nvp_rdev != vp->v_rdev || nvp->v_type != vp->v_type) 708 continue; 709 /* 710 * Alias, but not in use, so flush it out. 711 */ 712 if (vp->v_usecount == 0) { 713 vgone(vp); 714 goto loop; 715 } 716 if (vget(vp, 1)) 717 goto loop; 718 break; 719 } 720 if (vp == NULL || vp->v_tag != VT_NON) { 721 MALLOC(nvp->v_specinfo, struct specinfo *, 722 sizeof(struct specinfo), M_VNODE, M_WAITOK); 723 nvp->v_rdev = nvp_rdev; 724 nvp->v_hashchain = vpp; 725 nvp->v_specnext = *vpp; 726 nvp->v_specflags = 0; 727 *vpp = nvp; 728 if (vp != NULL) { 729 nvp->v_flag |= VALIASED; 730 vp->v_flag |= VALIASED; 731 vput(vp); 732 } 733 return (NULLVP); 734 } 735 VOP_UNLOCK(vp); 736 vclean(vp, 0); 737 vp->v_op = nvp->v_op; 738 vp->v_tag = nvp->v_tag; 739 nvp->v_type = VNON; 740 insmntque(vp, mp); 741 return (vp); 742 } 743 744 /* 745 * Grab a particular vnode from the free list, increment its 746 * reference count and lock it. The vnode lock bit is set the 747 * vnode is being eliminated in vgone. The process is awakened 748 * when the transition is completed, and an error returned to 749 * indicate that the vnode is no longer usable (possibly having 750 * been changed to a new file system type). 751 */ 752 int 753 vget(vp, lockflag) 754 register struct vnode *vp; 755 int lockflag; 756 { 757 758 /* 759 * If the vnode is in the process of being cleaned out for another 760 * use, we wait for the cleaning to finish and then return failure. 761 * Cleaning is determined either by checking that the VXLOCK flag is 762 * set, or that the use count is zero with the back pointer set to 763 * show that it has been removed from the free list by getnewvnode. 764 * The VXLOCK flag may not have been set yet because vclean is blocked 765 * in the VOP_LOCK call waiting for the VOP_INACTIVE to complete. 766 */ 767 if ((vp->v_flag & VXLOCK) || 768 (vp->v_usecount == 0 && 769 vp->v_freelist.tqe_prev == (struct vnode **) 0xdeadb)) { 770 vp->v_flag |= VXWANT; 771 (void) tsleep((caddr_t) vp, PINOD, "vget", 0); 772 return (1); 773 } 774 if (vp->v_usecount == 0) { 775 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 776 freevnodes--; 777 } 778 vp->v_usecount++; 779 if (lockflag) 780 VOP_LOCK(vp); 781 return (0); 782 } 783 784 /* 785 * Vnode reference, just increment the count 786 */ 787 void 788 vref(vp) 789 struct vnode *vp; 790 { 791 792 if (vp->v_usecount <= 0) 793 panic("vref used where vget required"); 794 vp->v_usecount++; 795 } 796 797 /* 798 * vput(), just unlock and vrele() 799 */ 800 void 801 vput(vp) 802 register struct vnode *vp; 803 { 804 805 VOP_UNLOCK(vp); 806 vrele(vp); 807 } 808 809 /* 810 * Vnode release. 811 * If count drops to zero, call inactive routine and return to freelist. 812 */ 813 void 814 vrele(vp) 815 register struct vnode *vp; 816 { 817 818 #ifdef DIAGNOSTIC 819 if (vp == NULL) 820 panic("vrele: null vp"); 821 #endif 822 vp->v_usecount--; 823 if (vp->v_usecount > 0) 824 return; 825 #ifdef DIAGNOSTIC 826 if (vp->v_usecount < 0 /* || vp->v_writecount < 0 */ ) { 827 vprint("vrele: negative ref count", vp); 828 panic("vrele: negative reference cnt"); 829 } 830 #endif 831 if (vp->v_flag & VAGE) { 832 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 833 vp->v_flag &= ~VAGE; 834 } else { 835 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 836 } 837 freevnodes++; 838 839 VOP_INACTIVE(vp); 840 } 841 842 #ifdef DIAGNOSTIC 843 /* 844 * Page or buffer structure gets a reference. 845 */ 846 void 847 vhold(vp) 848 register struct vnode *vp; 849 { 850 851 vp->v_holdcnt++; 852 } 853 854 /* 855 * Page or buffer structure frees a reference. 856 */ 857 void 858 holdrele(vp) 859 register struct vnode *vp; 860 { 861 862 if (vp->v_holdcnt <= 0) 863 panic("holdrele: holdcnt"); 864 vp->v_holdcnt--; 865 } 866 #endif /* DIAGNOSTIC */ 867 868 /* 869 * Remove any vnodes in the vnode table belonging to mount point mp. 870 * 871 * If MNT_NOFORCE is specified, there should not be any active ones, 872 * return error if any are found (nb: this is a user error, not a 873 * system error). If MNT_FORCE is specified, detach any active vnodes 874 * that are found. 875 */ 876 #ifdef DIAGNOSTIC 877 int busyprt = 0; /* print out busy vnodes */ 878 SYSCTL_INT(_debug, 1, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 879 #endif 880 881 int 882 vflush(mp, skipvp, flags) 883 struct mount *mp; 884 struct vnode *skipvp; 885 int flags; 886 { 887 register struct vnode *vp, *nvp; 888 int busy = 0; 889 890 if ((mp->mnt_flag & MNT_MPBUSY) == 0) 891 panic("vflush: not busy"); 892 loop: 893 for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) { 894 /* 895 * Make sure this vnode wasn't reclaimed in getnewvnode(). 896 * Start over if it has (it won't be on the list anymore). 897 */ 898 if (vp->v_mount != mp) 899 goto loop; 900 nvp = vp->v_mntvnodes.le_next; 901 /* 902 * Skip over a selected vnode. 903 */ 904 if (vp == skipvp) 905 continue; 906 /* 907 * Skip over a vnodes marked VSYSTEM. 908 */ 909 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) 910 continue; 911 /* 912 * If WRITECLOSE is set, only flush out regular file vnodes 913 * open for writing. 914 */ 915 if ((flags & WRITECLOSE) && 916 (vp->v_writecount == 0 || vp->v_type != VREG)) 917 continue; 918 /* 919 * With v_usecount == 0, all we need to do is clear out the 920 * vnode data structures and we are done. 921 */ 922 if (vp->v_usecount == 0) { 923 vgone(vp); 924 continue; 925 } 926 /* 927 * If FORCECLOSE is set, forcibly close the vnode. For block 928 * or character devices, revert to an anonymous device. For 929 * all other files, just kill them. 930 */ 931 if (flags & FORCECLOSE) { 932 if (vp->v_type != VBLK && vp->v_type != VCHR) { 933 vgone(vp); 934 } else { 935 vclean(vp, 0); 936 vp->v_op = spec_vnodeop_p; 937 insmntque(vp, (struct mount *) 0); 938 } 939 continue; 940 } 941 #ifdef DIAGNOSTIC 942 if (busyprt) 943 vprint("vflush: busy vnode", vp); 944 #endif 945 busy++; 946 } 947 if (busy) 948 return (EBUSY); 949 return (0); 950 } 951 952 /* 953 * Disassociate the underlying file system from a vnode. 954 */ 955 void 956 vclean(struct vnode *vp, int flags) 957 { 958 int active; 959 960 /* 961 * Check to see if the vnode is in use. If so we have to reference it 962 * before we clean it out so that its count cannot fall to zero and 963 * generate a race against ourselves to recycle it. 964 */ 965 if ((active = vp->v_usecount)) 966 VREF(vp); 967 /* 968 * Even if the count is zero, the VOP_INACTIVE routine may still have 969 * the object locked while it cleans it out. The VOP_LOCK ensures that 970 * the VOP_INACTIVE routine is done with its work. For active vnodes, 971 * it ensures that no other activity can occur while the underlying 972 * object is being cleaned out. 973 */ 974 VOP_LOCK(vp); 975 /* 976 * Prevent the vnode from being recycled or brought into use while we 977 * clean it out. 978 */ 979 if (vp->v_flag & VXLOCK) 980 panic("vclean: deadlock"); 981 vp->v_flag |= VXLOCK; 982 /* 983 * Clean out any buffers associated with the vnode. 984 */ 985 if (flags & DOCLOSE) 986 vinvalbuf(vp, V_SAVE, NOCRED, NULL, 0, 0); 987 /* 988 * Any other processes trying to obtain this lock must first wait for 989 * VXLOCK to clear, then call the new lock operation. 990 */ 991 VOP_UNLOCK(vp); 992 /* 993 * If purging an active vnode, it must be closed and deactivated 994 * before being reclaimed. 995 */ 996 if (active) { 997 if (flags & DOCLOSE) 998 VOP_CLOSE(vp, FNONBLOCK, NOCRED, NULL); 999 VOP_INACTIVE(vp); 1000 } 1001 /* 1002 * Reclaim the vnode. 1003 */ 1004 if (VOP_RECLAIM(vp)) 1005 panic("vclean: cannot reclaim"); 1006 if (active) 1007 vrele(vp); 1008 1009 /* 1010 * Done with purge, notify sleepers of the grim news. 1011 */ 1012 vp->v_op = dead_vnodeop_p; 1013 vp->v_tag = VT_NON; 1014 vp->v_flag &= ~VXLOCK; 1015 if (vp->v_flag & VXWANT) { 1016 vp->v_flag &= ~VXWANT; 1017 wakeup((caddr_t) vp); 1018 } 1019 } 1020 1021 /* 1022 * Eliminate all activity associated with the requested vnode 1023 * and with all vnodes aliased to the requested vnode. 1024 */ 1025 void 1026 vgoneall(vp) 1027 register struct vnode *vp; 1028 { 1029 register struct vnode *vq; 1030 1031 if (vp->v_flag & VALIASED) { 1032 /* 1033 * If a vgone (or vclean) is already in progress, wait until 1034 * it is done and return. 1035 */ 1036 if (vp->v_flag & VXLOCK) { 1037 vp->v_flag |= VXWANT; 1038 (void) tsleep((caddr_t) vp, PINOD, "vgall", 0); 1039 return; 1040 } 1041 /* 1042 * Ensure that vp will not be vgone'd while we are eliminating 1043 * its aliases. 1044 */ 1045 vp->v_flag |= VXLOCK; 1046 while (vp->v_flag & VALIASED) { 1047 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1048 if (vq->v_rdev != vp->v_rdev || 1049 vq->v_type != vp->v_type || vp == vq) 1050 continue; 1051 vgone(vq); 1052 break; 1053 } 1054 } 1055 /* 1056 * Remove the lock so that vgone below will really eliminate 1057 * the vnode after which time vgone will awaken any sleepers. 1058 */ 1059 vp->v_flag &= ~VXLOCK; 1060 } 1061 vgone(vp); 1062 } 1063 1064 /* 1065 * Eliminate all activity associated with a vnode 1066 * in preparation for reuse. 1067 */ 1068 void 1069 vgone(vp) 1070 register struct vnode *vp; 1071 { 1072 register struct vnode *vq; 1073 struct vnode *vx; 1074 1075 /* 1076 * If a vgone (or vclean) is already in progress, wait until it is 1077 * done and return. 1078 */ 1079 if (vp->v_flag & VXLOCK) { 1080 vp->v_flag |= VXWANT; 1081 (void) tsleep((caddr_t) vp, PINOD, "vgone", 0); 1082 return; 1083 } 1084 /* 1085 * Clean out the filesystem specific data. 1086 */ 1087 vclean(vp, DOCLOSE); 1088 /* 1089 * Delete from old mount point vnode list, if on one. 1090 */ 1091 if (vp->v_mount != NULL) { 1092 LIST_REMOVE(vp, v_mntvnodes); 1093 vp->v_mount = NULL; 1094 } 1095 /* 1096 * If special device, remove it from special device alias list. 1097 */ 1098 if (vp->v_type == VBLK || vp->v_type == VCHR) { 1099 if (*vp->v_hashchain == vp) { 1100 *vp->v_hashchain = vp->v_specnext; 1101 } else { 1102 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1103 if (vq->v_specnext != vp) 1104 continue; 1105 vq->v_specnext = vp->v_specnext; 1106 break; 1107 } 1108 if (vq == NULL) 1109 panic("missing bdev"); 1110 } 1111 if (vp->v_flag & VALIASED) { 1112 vx = NULL; 1113 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1114 if (vq->v_rdev != vp->v_rdev || 1115 vq->v_type != vp->v_type) 1116 continue; 1117 if (vx) 1118 break; 1119 vx = vq; 1120 } 1121 if (vx == NULL) 1122 panic("missing alias"); 1123 if (vq == NULL) 1124 vx->v_flag &= ~VALIASED; 1125 vp->v_flag &= ~VALIASED; 1126 } 1127 FREE(vp->v_specinfo, M_VNODE); 1128 vp->v_specinfo = NULL; 1129 } 1130 /* 1131 * If it is on the freelist and not already at the head, move it to 1132 * the head of the list. The test of the back pointer and the 1133 * reference count of zero is because it will be removed from the free 1134 * list by getnewvnode, but will not have its reference count 1135 * incremented until after calling vgone. If the reference count were 1136 * incremented first, vgone would (incorrectly) try to close the 1137 * previous instance of the underlying object. So, the back pointer is 1138 * explicitly set to `0xdeadb' in getnewvnode after removing it from 1139 * the freelist to ensure that we do not try to move it here. 1140 */ 1141 if (vp->v_usecount == 0 && 1142 vp->v_freelist.tqe_prev != (struct vnode **) 0xdeadb && 1143 vnode_free_list.tqh_first != vp) { 1144 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 1145 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 1146 } 1147 vp->v_type = VBAD; 1148 } 1149 1150 /* 1151 * Lookup a vnode by device number. 1152 */ 1153 int 1154 vfinddev(dev, type, vpp) 1155 dev_t dev; 1156 enum vtype type; 1157 struct vnode **vpp; 1158 { 1159 register struct vnode *vp; 1160 1161 for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { 1162 if (dev != vp->v_rdev || type != vp->v_type) 1163 continue; 1164 *vpp = vp; 1165 return (1); 1166 } 1167 return (0); 1168 } 1169 1170 /* 1171 * Calculate the total number of references to a special device. 1172 */ 1173 int 1174 vcount(vp) 1175 register struct vnode *vp; 1176 { 1177 register struct vnode *vq, *vnext; 1178 int count; 1179 1180 loop: 1181 if ((vp->v_flag & VALIASED) == 0) 1182 return (vp->v_usecount); 1183 for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) { 1184 vnext = vq->v_specnext; 1185 if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) 1186 continue; 1187 /* 1188 * Alias, but not in use, so flush it out. 1189 */ 1190 if (vq->v_usecount == 0 && vq != vp) { 1191 vgone(vq); 1192 goto loop; 1193 } 1194 count += vq->v_usecount; 1195 } 1196 return (count); 1197 } 1198 1199 /* 1200 * Print out a description of a vnode. 1201 */ 1202 static char *typename[] = 1203 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 1204 1205 void 1206 vprint(label, vp) 1207 char *label; 1208 register struct vnode *vp; 1209 { 1210 char buf[64]; 1211 1212 if (label != NULL) 1213 printf("%s: ", label); 1214 printf("type %s, usecount %d, writecount %d, refcount %ld,", 1215 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 1216 vp->v_holdcnt); 1217 buf[0] = '\0'; 1218 if (vp->v_flag & VROOT) 1219 strcat(buf, "|VROOT"); 1220 if (vp->v_flag & VTEXT) 1221 strcat(buf, "|VTEXT"); 1222 if (vp->v_flag & VSYSTEM) 1223 strcat(buf, "|VSYSTEM"); 1224 if (vp->v_flag & VXLOCK) 1225 strcat(buf, "|VXLOCK"); 1226 if (vp->v_flag & VXWANT) 1227 strcat(buf, "|VXWANT"); 1228 if (vp->v_flag & VBWAIT) 1229 strcat(buf, "|VBWAIT"); 1230 if (vp->v_flag & VALIASED) 1231 strcat(buf, "|VALIASED"); 1232 if (buf[0] != '\0') 1233 printf(" flags (%s)", &buf[1]); 1234 if (vp->v_data == NULL) { 1235 printf("\n"); 1236 } else { 1237 printf("\n\t"); 1238 VOP_PRINT(vp); 1239 } 1240 } 1241 1242 #ifdef DDB 1243 /* 1244 * List all of the locked vnodes in the system. 1245 * Called when debugging the kernel. 1246 */ 1247 void 1248 printlockedvnodes(void) 1249 { 1250 register struct mount *mp; 1251 register struct vnode *vp; 1252 1253 printf("Locked vnodes\n"); 1254 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; 1255 mp = mp->mnt_list.cqe_next) { 1256 for (vp = mp->mnt_vnodelist.lh_first; 1257 vp != NULL; 1258 vp = vp->v_mntvnodes.le_next) 1259 if (VOP_ISLOCKED(vp)) 1260 vprint((char *) 0, vp); 1261 } 1262 } 1263 #endif 1264 1265 int kinfo_vdebug = 1; 1266 int kinfo_vgetfailed; 1267 1268 #define KINFO_VNODESLOP 10 1269 /* 1270 * Dump vnode list (via sysctl). 1271 * Copyout address of vnode followed by vnode. 1272 */ 1273 /* ARGSUSED */ 1274 static int 1275 sysctl_vnode SYSCTL_HANDLER_ARGS 1276 { 1277 register struct mount *mp, *nmp; 1278 struct vnode *vp; 1279 int error; 1280 1281 #define VPTRSZ sizeof (struct vnode *) 1282 #define VNODESZ sizeof (struct vnode) 1283 1284 req->lock = 0; 1285 if (!req->oldptr) /* Make an estimate */ 1286 return (SYSCTL_OUT(req, 0, 1287 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 1288 1289 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { 1290 nmp = mp->mnt_list.cqe_next; 1291 if (vfs_busy(mp)) 1292 continue; 1293 again: 1294 for (vp = mp->mnt_vnodelist.lh_first; 1295 vp != NULL; 1296 vp = vp->v_mntvnodes.le_next) { 1297 /* 1298 * Check that the vp is still associated with this 1299 * filesystem. RACE: could have been recycled onto 1300 * the same filesystem. 1301 */ 1302 if (vp->v_mount != mp) { 1303 if (kinfo_vdebug) 1304 printf("kinfo: vp changed\n"); 1305 goto again; 1306 } 1307 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 1308 (error = SYSCTL_OUT(req, vp, VNODESZ))) { 1309 vfs_unbusy(mp); 1310 return (error); 1311 } 1312 } 1313 vfs_unbusy(mp); 1314 } 1315 1316 return (0); 1317 } 1318 1319 SYSCTL_NODE(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 1320 sysctl_vnode, ""); 1321 1322 1323 /* 1324 * Check to see if a filesystem is mounted on a block device. 1325 */ 1326 int 1327 vfs_mountedon(vp) 1328 register struct vnode *vp; 1329 { 1330 register struct vnode *vq; 1331 1332 if (vp->v_specflags & SI_MOUNTEDON) 1333 return (EBUSY); 1334 if (vp->v_flag & VALIASED) { 1335 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1336 if (vq->v_rdev != vp->v_rdev || 1337 vq->v_type != vp->v_type) 1338 continue; 1339 if (vq->v_specflags & SI_MOUNTEDON) 1340 return (EBUSY); 1341 } 1342 } 1343 return (0); 1344 } 1345 1346 /* 1347 * Build hash lists of net addresses and hang them off the mount point. 1348 * Called by ufs_mount() to set up the lists of export addresses. 1349 */ 1350 static int 1351 vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 1352 struct export_args *argp) 1353 { 1354 register struct netcred *np; 1355 register struct radix_node_head *rnh; 1356 register int i; 1357 struct radix_node *rn; 1358 struct sockaddr *saddr, *smask = 0; 1359 struct domain *dom; 1360 int error; 1361 1362 if (argp->ex_addrlen == 0) { 1363 if (mp->mnt_flag & MNT_DEFEXPORTED) 1364 return (EPERM); 1365 np = &nep->ne_defexported; 1366 np->netc_exflags = argp->ex_flags; 1367 np->netc_anon = argp->ex_anon; 1368 np->netc_anon.cr_ref = 1; 1369 mp->mnt_flag |= MNT_DEFEXPORTED; 1370 return (0); 1371 } 1372 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 1373 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK); 1374 bzero((caddr_t) np, i); 1375 saddr = (struct sockaddr *) (np + 1); 1376 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) 1377 goto out; 1378 if (saddr->sa_len > argp->ex_addrlen) 1379 saddr->sa_len = argp->ex_addrlen; 1380 if (argp->ex_masklen) { 1381 smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen); 1382 error = copyin(argp->ex_addr, (caddr_t) smask, argp->ex_masklen); 1383 if (error) 1384 goto out; 1385 if (smask->sa_len > argp->ex_masklen) 1386 smask->sa_len = argp->ex_masklen; 1387 } 1388 i = saddr->sa_family; 1389 if ((rnh = nep->ne_rtable[i]) == 0) { 1390 /* 1391 * Seems silly to initialize every AF when most are not used, 1392 * do so on demand here 1393 */ 1394 for (dom = domains; dom; dom = dom->dom_next) 1395 if (dom->dom_family == i && dom->dom_rtattach) { 1396 dom->dom_rtattach((void **) &nep->ne_rtable[i], 1397 dom->dom_rtoffset); 1398 break; 1399 } 1400 if ((rnh = nep->ne_rtable[i]) == 0) { 1401 error = ENOBUFS; 1402 goto out; 1403 } 1404 } 1405 rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh, 1406 np->netc_rnodes); 1407 if (rn == 0 || np != (struct netcred *) rn) { /* already exists */ 1408 error = EPERM; 1409 goto out; 1410 } 1411 np->netc_exflags = argp->ex_flags; 1412 np->netc_anon = argp->ex_anon; 1413 np->netc_anon.cr_ref = 1; 1414 return (0); 1415 out: 1416 free(np, M_NETADDR); 1417 return (error); 1418 } 1419 1420 /* ARGSUSED */ 1421 static int 1422 vfs_free_netcred(struct radix_node *rn, void *w) 1423 { 1424 register struct radix_node_head *rnh = (struct radix_node_head *) w; 1425 1426 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 1427 free((caddr_t) rn, M_NETADDR); 1428 return (0); 1429 } 1430 1431 /* 1432 * Free the net address hash lists that are hanging off the mount points. 1433 */ 1434 static void 1435 vfs_free_addrlist(struct netexport *nep) 1436 { 1437 register int i; 1438 register struct radix_node_head *rnh; 1439 1440 for (i = 0; i <= AF_MAX; i++) 1441 if ((rnh = nep->ne_rtable[i])) { 1442 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, 1443 (caddr_t) rnh); 1444 free((caddr_t) rnh, M_RTABLE); 1445 nep->ne_rtable[i] = 0; 1446 } 1447 } 1448 1449 int 1450 vfs_export(mp, nep, argp) 1451 struct mount *mp; 1452 struct netexport *nep; 1453 struct export_args *argp; 1454 { 1455 int error; 1456 1457 if (argp->ex_flags & MNT_DELEXPORT) { 1458 vfs_free_addrlist(nep); 1459 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 1460 } 1461 if (argp->ex_flags & MNT_EXPORTED) { 1462 if ((error = vfs_hang_addrlist(mp, nep, argp))) 1463 return (error); 1464 mp->mnt_flag |= MNT_EXPORTED; 1465 } 1466 return (0); 1467 } 1468 1469 struct netcred * 1470 vfs_export_lookup(mp, nep, nam) 1471 register struct mount *mp; 1472 struct netexport *nep; 1473 struct mbuf *nam; 1474 { 1475 register struct netcred *np; 1476 register struct radix_node_head *rnh; 1477 struct sockaddr *saddr; 1478 1479 np = NULL; 1480 if (mp->mnt_flag & MNT_EXPORTED) { 1481 /* 1482 * Lookup in the export list first. 1483 */ 1484 if (nam != NULL) { 1485 saddr = mtod(nam, struct sockaddr *); 1486 rnh = nep->ne_rtable[saddr->sa_family]; 1487 if (rnh != NULL) { 1488 np = (struct netcred *) 1489 (*rnh->rnh_matchaddr) ((caddr_t) saddr, 1490 rnh); 1491 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 1492 np = NULL; 1493 } 1494 } 1495 /* 1496 * If no address match, use the default if it exists. 1497 */ 1498 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 1499 np = &nep->ne_defexported; 1500 } 1501 return (np); 1502 } 1503 1504 1505 /* 1506 * perform msync on all vnodes under a mount point 1507 * the mount point must be locked. 1508 */ 1509 void 1510 vfs_msync(struct mount *mp, int flags) { 1511 struct vnode *vp; 1512 loop: 1513 for (vp = mp->mnt_vnodelist.lh_first; 1514 vp != NULL; 1515 vp = vp->v_mntvnodes.le_next) { 1516 1517 if (vp->v_mount != mp) 1518 goto loop; 1519 if (VOP_ISLOCKED(vp) && (flags != MNT_WAIT)) 1520 continue; 1521 if (vp->v_object && 1522 (((vm_object_t) vp->v_object)->flags & OBJ_MIGHTBEDIRTY)) { 1523 vm_object_page_clean(vp->v_object, 0, 0, TRUE, TRUE); 1524 } 1525 } 1526 } 1527