1185029Spjd/*- 2185029Spjd * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3185029Spjd * All rights reserved. 4185029Spjd * 5185029Spjd * Redistribution and use in source and binary forms, with or without 6185029Spjd * modification, are permitted provided that the following conditions 7185029Spjd * are met: 8185029Spjd * 1. Redistributions of source code must retain the above copyright 9185029Spjd * notice, this list of conditions and the following disclaimer. 10185029Spjd * 2. Redistributions in binary form must reproduce the above copyright 11185029Spjd * notice, this list of conditions and the following disclaimer in the 12185029Spjd * documentation and/or other materials provided with the distribution. 13185029Spjd * 14185029Spjd * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 15185029Spjd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16185029Spjd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17185029Spjd * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 18185029Spjd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19185029Spjd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20185029Spjd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21185029Spjd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22185029Spjd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23185029Spjd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24185029Spjd * SUCH DAMAGE. 25185029Spjd */ 26185029Spjd 27185029Spjd#include <sys/cdefs.h> 28185029Spjd__FBSDID("$FreeBSD$"); 29185029Spjd 30185029Spjd#include <sys/param.h> 31185029Spjd#include <sys/kernel.h> 32185029Spjd#include <sys/systm.h> 33185029Spjd#include <sys/pathname.h> 34185029Spjd#include <sys/vfs.h> 35185029Spjd#include <sys/vnode.h> 36185029Spjd 37185029Spjdint 38185029Spjdlookupname(char *dirname, enum uio_seg seg, enum symfollow follow, 39185029Spjd vnode_t **dirvpp, vnode_t **compvpp) 40185029Spjd{ 41185029Spjd 42185029Spjd return (lookupnameat(dirname, seg, follow, dirvpp, compvpp, NULL)); 43185029Spjd} 44185029Spjd 45185029Spjdint 46185029Spjdlookupnameat(char *dirname, enum uio_seg seg, enum symfollow follow, 47185029Spjd vnode_t **dirvpp, vnode_t **compvpp, vnode_t *startvp) 48185029Spjd{ 49185029Spjd struct nameidata nd; 50185029Spjd int error, ltype; 51185029Spjd 52185029Spjd ASSERT(dirvpp == NULL); 53185029Spjd 54185029Spjd vref(startvp); 55185029Spjd ltype = VOP_ISLOCKED(startvp); 56185029Spjd VOP_UNLOCK(startvp, 0); 57185029Spjd NDINIT_ATVP(&nd, LOOKUP, LOCKLEAF | MPSAFE | follow, seg, dirname, 58185029Spjd startvp, curthread); 59185029Spjd error = namei(&nd); 60185029Spjd *compvpp = nd.ni_vp; 61185029Spjd NDFREE(&nd, NDF_ONLY_PNBUF); 62185029Spjd vn_lock(startvp, ltype | LK_RETRY); 63185029Spjd return (error); 64185029Spjd} 65185029Spjd 66185029Spjdint 67185029Spjdtraverse(vnode_t **cvpp, int lktype) 68185029Spjd{ 69185029Spjd vnode_t *cvp; 70185029Spjd vnode_t *tvp; 71185029Spjd vfs_t *vfsp; 72185029Spjd int error; 73185029Spjd 74185029Spjd cvp = *cvpp; 75185029Spjd tvp = NULL; 76185029Spjd 77185029Spjd /* 78185029Spjd * If this vnode is mounted on, then we transparently indirect 79185029Spjd * to the vnode which is the root of the mounted file system. 80185029Spjd * Before we do this we must check that an unmount is not in 81185029Spjd * progress on this vnode. 82185029Spjd */ 83185029Spjd 84185029Spjd for (;;) { 85185029Spjd /* 86185029Spjd * Reached the end of the mount chain? 87185029Spjd */ 88185029Spjd vfsp = vn_mountedvfs(cvp); 89185029Spjd if (vfsp == NULL) 90185029Spjd break; 91243484Savg error = vfs_busy(vfsp, 0); 92185029Spjd /* 93185029Spjd * tvp is NULL for *cvpp vnode, which we can't unlock. 94185029Spjd */ 95185029Spjd if (tvp != NULL) 96185029Spjd vput(cvp); 97185029Spjd else 98185029Spjd vrele(cvp); 99243484Savg if (error) 100243484Savg return (error); 101185029Spjd 102185029Spjd /* 103185029Spjd * The read lock must be held across the call to VFS_ROOT() to 104185029Spjd * prevent a concurrent unmount from destroying the vfs. 105185029Spjd */ 106191990Sattilio error = VFS_ROOT(vfsp, lktype, &tvp); 107243484Savg vfs_unbusy(vfsp); 108185029Spjd if (error != 0) 109185029Spjd return (error); 110185029Spjd cvp = tvp; 111185029Spjd } 112185029Spjd 113185029Spjd *cvpp = cvp; 114185029Spjd return (0); 115185029Spjd} 116