freebsd-dev/sys/fs/portalfs/portal_vfsops.c
David Greenman 2f9bae59d6 Moved the fsnode MALLOC to before the call to getnewvnode() so that the
process won't possibly block before filling in the fsnode pointer (v_data)
which might be dereferenced during a sync since the vnode is put on the
mnt_vnodelist by getnewvnode.

Pointed out by Matt Day <mday@artisoft.com>
1996-06-12 03:37:57 +00:00

351 lines
8.5 KiB
C

/*
* Copyright (c) 1992, 1993
* 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.
*
* @(#)portal_vfsops.c 8.6 (Berkeley) 1/21/94
*
* $Id: portal_vfsops.c,v 1.10 1995/12/11 09:24:43 phk Exp $
*/
/*
* Portal Filesystem
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/proc.h>
#include <sys/filedesc.h>
#include <sys/file.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/domain.h>
#include <sys/un.h>
#include <miscfs/portal/portal.h>
static int portal_init __P((void));
static int portal_mount __P((struct mount *mp, char *path, caddr_t data,
struct nameidata *ndp, struct proc *p));
static int portal_start __P((struct mount *mp, int flags, struct proc *p));
static int portal_unmount __P((struct mount *mp, int mntflags,
struct proc *p));
static int portal_root __P((struct mount *mp, struct vnode **vpp));
static int portal_quotactl __P((struct mount *mp, int cmd, uid_t uid,
caddr_t arg, struct proc *p));
static int portal_statfs __P((struct mount *mp, struct statfs *sbp,
struct proc *p));
static int portal_sync __P((struct mount *mp, int waitfor,
struct ucred *cred, struct proc *p));
static int portal_vget __P((struct mount *mp, ino_t ino,
struct vnode **vpp));
static int portal_fhtovp __P((struct mount *mp, struct fid *fhp,
struct mbuf *nam, struct vnode **vpp,
int *exflagsp, struct ucred **credanonp));
static int portal_vptofh __P((struct vnode *vp, struct fid *fhp));
static int
portal_init()
{
return (0);
}
/*
* Mount the per-process file descriptors (/dev/fd)
*/
static int
portal_mount(mp, path, data, ndp, p)
struct mount *mp;
char *path;
caddr_t data;
struct nameidata *ndp;
struct proc *p;
{
struct file *fp;
struct portal_args args;
struct portalmount *fmp;
struct socket *so;
struct vnode *rvp;
struct portalnode *pn;
u_int size;
int error;
/*
* Update is a no-op
*/
if (mp->mnt_flag & MNT_UPDATE)
return (EOPNOTSUPP);
error = copyin(data, (caddr_t) &args, sizeof(struct portal_args));
if (error)
return (error);
error = getsock(p->p_fd, args.pa_socket, &fp);
if (error)
return (error);
so = (struct socket *) fp->f_data;
if (so->so_proto->pr_domain->dom_family != AF_UNIX)
return (ESOCKTNOSUPPORT);
MALLOC(pn, struct portalnode *, sizeof(struct portalnode),
M_TEMP, M_WAITOK);
MALLOC(fmp, struct portalmount *, sizeof(struct portalmount),
M_UFSMNT, M_WAITOK); /* XXX */
error = getnewvnode(VT_PORTAL, mp, portal_vnodeop_p, &rvp); /* XXX */
if (error) {
FREE(fmp, M_UFSMNT);
FREE(pn, M_TEMP);
return (error);
}
rvp->v_data = pn;
rvp->v_type = VDIR;
rvp->v_flag |= VROOT;
VTOPORTAL(rvp)->pt_arg = 0;
VTOPORTAL(rvp)->pt_size = 0;
VTOPORTAL(rvp)->pt_fileid = PORTAL_ROOTFILEID;
fmp->pm_root = rvp;
fmp->pm_server = fp; fp->f_count++;
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_data = (qaddr_t) fmp;
getnewfsid(mp, MOUNT_PORTAL);
(void)copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
(void)copyinstr(args.pa_config,
mp->mnt_stat.f_mntfromname, MNAMELEN - 1, &size);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
#ifdef notdef
bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
bcopy("portal", mp->mnt_stat.f_mntfromname, sizeof("portal"));
#endif
return (0);
}
static int
portal_start(mp, flags, p)
struct mount *mp;
int flags;
struct proc *p;
{
return (0);
}
static int
portal_unmount(mp, mntflags, p)
struct mount *mp;
int mntflags;
struct proc *p;
{
struct vnode *rootvp = VFSTOPORTAL(mp)->pm_root;
int error, flags = 0;
if (mntflags & MNT_FORCE) {
/* portal can never be rootfs so don't check for it */
if (!doforce)
return (EINVAL);
flags |= FORCECLOSE;
}
/*
* Clear out buffer cache. I don't think we
* ever get anything cached at this level at the
* moment, but who knows...
*/
#ifdef notyet
mntflushbuf(mp, 0);
if (mntinvalbuf(mp, 1))
return (EBUSY);
#endif
if (rootvp->v_usecount > 1)
return (EBUSY);
error = vflush(mp, rootvp, flags);
if (error)
return (error);
/*
* Release reference on underlying root vnode
*/
vrele(rootvp);
/*
* And blow it away for future re-use
*/
vgone(rootvp);
/*
* Shutdown the socket. This will cause the select in the
* daemon to wake up, and then the accept will get ECONNABORTED
* which it interprets as a request to go and bury itself.
*/
soshutdown((struct socket *) VFSTOPORTAL(mp)->pm_server->f_data, 2);
/*
* Discard reference to underlying file. Must call closef because
* this may be the last reference.
*/
closef(VFSTOPORTAL(mp)->pm_server, (struct proc *) 0);
/*
* Finally, throw away the portalmount structure
*/
free(mp->mnt_data, M_UFSMNT); /* XXX */
mp->mnt_data = 0;
return (0);
}
static int
portal_root(mp, vpp)
struct mount *mp;
struct vnode **vpp;
{
struct vnode *vp;
/*
* Return locked reference to root.
*/
vp = VFSTOPORTAL(mp)->pm_root;
VREF(vp);
VOP_LOCK(vp);
*vpp = vp;
return (0);
}
static int
portal_quotactl(mp, cmd, uid, arg, p)
struct mount *mp;
int cmd;
uid_t uid;
caddr_t arg;
struct proc *p;
{
return (EOPNOTSUPP);
}
static int
portal_statfs(mp, sbp, p)
struct mount *mp;
struct statfs *sbp;
struct proc *p;
{
sbp->f_type = MOUNT_PORTAL;
sbp->f_flags = 0;
sbp->f_bsize = DEV_BSIZE;
sbp->f_iosize = DEV_BSIZE;
sbp->f_blocks = 2; /* 1K to keep df happy */
sbp->f_bfree = 0;
sbp->f_bavail = 0;
sbp->f_files = 1; /* Allow for "." */
sbp->f_ffree = 0; /* See comments above */
if (sbp != &mp->mnt_stat) {
bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
}
return (0);
}
static int
portal_sync(mp, waitfor, cred, p)
struct mount *mp;
int waitfor;
struct ucred *cred;
struct proc *p;
{
return (0);
}
static int
portal_vget(mp, ino, vpp)
struct mount *mp;
ino_t ino;
struct vnode **vpp;
{
return (EOPNOTSUPP);
}
static int
portal_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
struct mount *mp;
struct fid *fhp;
struct mbuf *nam;
struct vnode **vpp;
int *exflagsp;
struct ucred **credanonp;
{
return (EOPNOTSUPP);
}
static int
portal_vptofh(vp, fhp)
struct vnode *vp;
struct fid *fhp;
{
return (EOPNOTSUPP);
}
static struct vfsops portal_vfsops = {
portal_mount,
portal_start,
portal_unmount,
portal_root,
portal_quotactl,
portal_statfs,
portal_sync,
portal_vget,
portal_fhtovp,
portal_vptofh,
portal_init,
};
VFS_SET(portal_vfsops, portal, MOUNT_PORTAL, VFCF_SYNTHETIC);