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/*-
* Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/pathname.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
int
lookupname(char *dirname, enum uio_seg seg, enum symfollow follow,
vnode_t **dirvpp, vnode_t **compvpp)
{
return (lookupnameat(dirname, seg, follow, dirvpp, compvpp, NULL));
}
int
lookupnameat(char *dirname, enum uio_seg seg, enum symfollow follow,
vnode_t **dirvpp, vnode_t **compvpp, vnode_t *startvp)
{
struct nameidata nd;
int error, ltype;
ASSERT(dirvpp == NULL);
vref(startvp);
ltype = VOP_ISLOCKED(startvp);
VOP_UNLOCK(startvp, 0);
NDINIT_ATVP(&nd, LOOKUP, LOCKLEAF | MPSAFE | follow, seg, dirname,
startvp, curthread);
error = namei(&nd);
*compvpp = nd.ni_vp;
NDFREE(&nd, NDF_ONLY_PNBUF);
vn_lock(startvp, ltype | LK_RETRY);
return (error);
}
int
traverse(vnode_t **cvpp, int lktype)
{
kthread_t *td = curthread;
vnode_t *cvp;
vnode_t *tvp;
vfs_t *vfsp;
int error;
cvp = *cvpp;
tvp = NULL;
/*
* If this vnode is mounted on, then we transparently indirect
* to the vnode which is the root of the mounted file system.
* Before we do this we must check that an unmount is not in
* progress on this vnode.
*/
for (;;) {
/*
* Reached the end of the mount chain?
*/
vfsp = vn_mountedvfs(cvp);
if (vfsp == NULL)
break;
/*
* tvp is NULL for *cvpp vnode, which we can't unlock.
*/
if (tvp != NULL)
vput(cvp);
else
vrele(cvp);
/*
* The read lock must be held across the call to VFS_ROOT() to
* prevent a concurrent unmount from destroying the vfs.
*/
error = VFS_ROOT(vfsp, lktype, &tvp, td);
if (error != 0)
return (error);
cvp = tvp;
}
*cvpp = cvp;
return (0);
}
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