freebsd-skq/sys/fs/devfs/devfs_vfsops.c
Dima Dorfman a1dc209638 Introduce the DEVFS "rule" subsystem. DEVFS rules permit the
administrator to define certain properties of new devfs nodes before
they become visible to the userland.  Both static (e.g., /dev/speaker)
and dynamic (e.g., /dev/bpf*, some removable devices) nodes are
supported.  Each DEVFS mount may have a different ruleset assigned to
it, permitting different policies to be implemented for things like
jails.

Approved by:	phk
2002-07-17 01:46:48 +00:00

201 lines
4.9 KiB
C

/*
* Copyright (c) 1992, 1993, 1995
* The Regents of the University of California. All rights reserved.
* Copyright (c) 2000
* Poul-Henning Kamp. 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. 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.
*
* @(#)kernfs_vfsops.c 8.10 (Berkeley) 5/14/95
* From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36
*
* $FreeBSD$
*/
#include "opt_devfs.h"
#ifndef NODEVFS
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <fs/devfs/devfs.h>
MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data");
static int devfs_mount(struct mount *mp, struct nameidata *ndp,
struct thread *td);
static int devfs_unmount(struct mount *mp, int mntflags,
struct thread *td);
static int devfs_root(struct mount *mp, struct vnode **vpp);
static int devfs_statfs(struct mount *mp, struct statfs *sbp,
struct thread *td);
/*
* Mount the filesystem
*/
static int
devfs_mount(mp, ndp, td)
struct mount *mp;
struct nameidata *ndp;
struct thread *td;
{
int error;
struct devfs_mount *fmp;
struct vnode *rvp;
error = 0;
/*
* XXX: flag changes.
*/
if (mp->mnt_flag & MNT_UPDATE)
return (EOPNOTSUPP);
MALLOC(fmp, struct devfs_mount *, sizeof(struct devfs_mount),
M_DEVFS, M_WAITOK | M_ZERO);
lockinit(&fmp->dm_lock, PVFS, "devfs", 0, LK_NOPAUSE);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_data = (qaddr_t) fmp;
vfs_getnewfsid(mp);
fmp->dm_inode = DEVFSINOMOUNT;
fmp->dm_rootdir = devfs_vmkdir("(root)", 6, NULL);
fmp->dm_rootdir->de_inode = 2;
fmp->dm_basedir = fmp->dm_rootdir;
devfs_rules_newmount(fmp, td);
error = devfs_root(mp, &rvp);
if (error) {
lockdestroy(&fmp->dm_lock);
FREE(fmp, M_DEVFS);
return (error);
}
VOP_UNLOCK(rvp, 0, td);
bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
bcopy("devfs", mp->mnt_stat.f_mntfromname, sizeof("devfs"));
(void)devfs_statfs(mp, &mp->mnt_stat, td);
return (0);
}
static int
devfs_unmount(mp, mntflags, td)
struct mount *mp;
int mntflags;
struct thread *td;
{
int error;
int flags = 0;
struct devfs_mount *fmp;
fmp = VFSTODEVFS(mp);
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
/* There is 1 extra root vnode reference from devfs_mount(). */
error = vflush(mp, 1, flags);
if (error)
return (error);
devfs_purge(fmp->dm_rootdir);
mp->mnt_data = 0;
lockdestroy(&fmp->dm_lock);
free(fmp, M_DEVFS);
return 0;
}
/* Return locked reference to root. */
static int
devfs_root(mp, vpp)
struct mount *mp;
struct vnode **vpp;
{
int error;
struct thread *td;
struct vnode *vp;
struct devfs_mount *dmp;
td = curthread; /* XXX */
dmp = VFSTODEVFS(mp);
error = devfs_allocv(dmp->dm_rootdir, mp, &vp, td);
if (error)
return (error);
vp->v_flag |= VROOT;
*vpp = vp;
return (0);
}
static int
devfs_statfs(mp, sbp, td)
struct mount *mp;
struct statfs *sbp;
struct thread *td;
{
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 = 0;
sbp->f_ffree = 0;
if (sbp != &mp->mnt_stat) {
sbp->f_type = mp->mnt_vfc->vfc_typenum;
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 struct vfsops devfs_vfsops = {
NULL,
vfs_stdstart,
devfs_unmount,
devfs_root,
vfs_stdquotactl,
devfs_statfs,
vfs_stdsync,
vfs_stdvget,
vfs_stdfhtovp,
vfs_stdcheckexp,
vfs_stdvptofh,
vfs_stdinit,
vfs_stduninit,
vfs_stdextattrctl,
devfs_mount,
};
VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC);
#endif