NetBSD/sys/miscfs/genfs/layer_vfsops.c
wrstuden 9866514df5 Introduce layer library in genfs. This set of files abstracts most of
the functionality of nullfs. The latter is now just a mount & unmount
routine, and a few tables. umapfs borrow most of this infrastructure.

Both fs's are now nfs-exportable.

All layered fs's share a common format to private mount & private
vnode structs (which a particular fs can extend).

Also add genfs_noerr_rele(), a vnode op which will vrele/vput
operand vnodes appropriately.
1999-07-08 01:18:59 +00:00

286 lines
7.8 KiB
C

/* $NetBSD: layer_vfsops.c,v 1.1 1999/07/08 01:19:01 wrstuden Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
* All rights reserved.
*
* This software was written by William Studenmund of the
* Numerical Aerospace Similation Facility, NASA Ames Research Center.
*
* 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.
* 3. Neither the the name of the National Aeronautics & Space Administration
* nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION
* ``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 ADMINISTRATION OR CONTRIB-
* UTORS 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.
*/
/*
* Copyright (c) 1992, 1993, 1995
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software donated to Berkeley by
* Jan-Simon Pendry.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* from: Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp
* from: @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92
* @(#)null_vfsops.c 8.7 (Berkeley) 5/14/95
*/
/*
* generic layer vfs ops.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <sys/types.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <miscfs/genfs/layer.h>
#include <miscfs/genfs/layer_extern.h>
/*
* VFS start. Nothing needed here - the start routine
* on the underlying filesystem will have been called
* when that filesystem was mounted.
*/
int
layerfs_start(mp, flags, p)
struct mount *mp;
int flags;
struct proc *p;
{
return (0);
/* return VFS_START(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, flags, p); */
}
int
layerfs_root(mp, vpp)
struct mount *mp;
struct vnode **vpp;
{
struct vnode *vp;
#ifdef LAYERFS_DIAGNOSTIC
printf("layerfs_root(mp = %p, vp = %p->%p)\n", mp,
MOUNTTOLAYERMOUNT(mp)->layerm_rootvp,
LAYERVPTOLOWERVP(MOUNTTOLAYERMOUNT(mp)->layerm_rootvp));
#endif
/*
* Return locked reference to root.
*/
vp = MOUNTTOLAYERMOUNT(mp)->layerm_rootvp;
if (vp == NULL) {
*vpp = NULL;
return (EINVAL);
}
VREF(vp);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
*vpp = vp;
return 0;
}
int
layerfs_quotactl(mp, cmd, uid, arg, p)
struct mount *mp;
int cmd;
uid_t uid;
caddr_t arg;
struct proc *p;
{
return VFS_QUOTACTL(MOUNTTOLAYERMOUNT(mp)->layerm_vfs,
cmd, uid, arg, p);
}
int
layerfs_statfs(mp, sbp, p)
struct mount *mp;
struct statfs *sbp;
struct proc *p;
{
int error;
struct statfs mstat;
#ifdef LAYERFS_DIAGNOSTIC
printf("layerfs_statfs(mp = %p, vp = %p->%p)\n", mp,
MOUNTTOLAYERMOUNT(mp)->layerm_rootvp,
LAYERVPTOLOWERVP(MOUNTTOLAYERMOUNT(mp)->layerm_rootvp));
#endif
memset(&mstat, 0, sizeof(mstat));
error = VFS_STATFS(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, &mstat, p);
if (error)
return (error);
/* now copy across the "interesting" information and fake the rest */
sbp->f_type = mstat.f_type;
sbp->f_flags = mstat.f_flags;
sbp->f_bsize = mstat.f_bsize;
sbp->f_iosize = mstat.f_iosize;
sbp->f_blocks = mstat.f_blocks;
sbp->f_bfree = mstat.f_bfree;
sbp->f_bavail = mstat.f_bavail;
sbp->f_files = mstat.f_files;
sbp->f_ffree = mstat.f_ffree;
if (sbp != &mp->mnt_stat) {
memcpy(&sbp->f_fsid, &mp->mnt_stat.f_fsid, sizeof(sbp->f_fsid));
memcpy(sbp->f_mntonname, mp->mnt_stat.f_mntonname, MNAMELEN);
memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname, MNAMELEN);
}
strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN);
return (0);
}
int
layerfs_sync(mp, waitfor, cred, p)
struct mount *mp;
int waitfor;
struct ucred *cred;
struct proc *p;
{
/*
* XXX - Assumes no data cached at layer.
*/
return (0);
}
int
layerfs_vget(mp, ino, vpp)
struct mount *mp;
ino_t ino;
struct vnode **vpp;
{
int error;
struct vnode *vp;
if ((error = VFS_VGET(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, ino, &vp))) {
*vpp = NULL;
return (error);
}
if ((error = layer_node_create(mp, vp, vpp))) {
vput(vp);
*vpp = NULL;
return (error);
}
return (0);
}
int
layerfs_fhtovp(mp, fidp, vpp)
struct mount *mp;
struct fid *fidp;
struct vnode **vpp;
{
int error;
struct vnode *vp;
if ((error = VFS_FHTOVP(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, fidp, &vp)))
return (error);
if ((error = layer_node_create(mp, vp, vpp))) {
vput(vp);
*vpp = NULL;
return (error);
}
return (0);
}
int
layerfs_checkexp(mp, nam, exflagsp, credanonp)
struct mount *mp;
struct mbuf *nam;
int *exflagsp;
struct ucred**credanonp;
{
struct netcred *np;
struct layer_mount *lmp = MOUNTTOLAYERMOUNT(mp);
/*
* get the export permission structure for this <mp, client> tuple.
*/
if ((np = vfs_export_lookup(mp, &lmp->layerm_export, nam)) == NULL)
return (EACCES);
*exflagsp = np->netc_exflags;
*credanonp = &np->netc_anon;
return (0);
}
int
layerfs_vptofh(vp, fhp)
struct vnode *vp;
struct fid *fhp;
{
return (VFS_VPTOFH(LAYERVPTOLOWERVP(vp), fhp));
}
int
layerfs_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
int *name;
u_int namelen;
void *oldp;
size_t *oldlenp;
void *newp;
size_t newlen;
struct proc *p;
{
return (EOPNOTSUPP);
}