freebsd-dev/sys/fs/devfs/devfs_vfsops.c
Adrian Chadd f3a90da995 Reviewed by: jlemon
An initial tidyup of the mount() syscall and VFS mount code.

This code replaces the earlier work done by jlemon in an attempt to
make linux_mount() work.

* the guts of the mount work has been moved into vfs_mount().

* move `type', `path' and `flags' from being userland variables into being
  kernel variables in vfs_mount(). `data' remains a pointer into
  userspace.

* Attempt to verify the `type' and `path' strings passed to vfs_mount()
  aren't too long.

* rework mount() and linux_mount() to take the userland parameters
  (besides data, as mentioned) and pass kernel variables to vfs_mount().
  (linux_mount() already did this, I've just tidied it up a little more.)

* remove the copyin*() stuff for `path'. `data' still requires copyin*()
  since its a pointer into userland.

* set `mount->mnt_statf_mntonname' in vfs_mount() rather than in each
  filesystem.  This variable is generally initialised with `path', and
  each filesystem can override it if they want to.

* NOTE: f_mntonname is intiailised with "/" in the case of a root mount.
2001-03-01 21:00:17 +00:00

207 lines
5.0 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"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/malloc.h>
#include <fs/devfs/devfs.h>
MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data");
static int devfs_mount __P((struct mount *mp, char *path, caddr_t data,
struct nameidata *ndp, struct proc *p));
static int devfs_unmount __P((struct mount *mp, int mntflags,
struct proc *p));
static int devfs_root __P((struct mount *mp, struct vnode **vpp));
static int devfs_statfs __P((struct mount *mp, struct statfs *sbp,
struct proc *p));
/*
* Mount the filesystem
*/
static int
devfs_mount(mp, path, data, ndp, p)
struct mount *mp;
char *path;
caddr_t data;
struct nameidata *ndp;
struct proc *p;
{
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;
error = devfs_root(mp, &rvp);
if (error) {
lockdestroy(&fmp->dm_lock);
FREE(fmp, M_DEVFS);
return (error);
}
VOP_UNLOCK(rvp, 0, p);
bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
bcopy("devfs", mp->mnt_stat.f_mntfromname, sizeof("devfs"));
(void)devfs_statfs(mp, &mp->mnt_stat, p);
return (0);
}
static int
devfs_unmount(mp, mntflags, p)
struct mount *mp;
int mntflags;
struct proc *p;
{
int error;
int flags = 0;
struct vnode *rootvp;
struct devfs_mount *fmp;
error = devfs_root(mp, &rootvp);
if (error)
return (error);
fmp = VFSTODEVFS(mp);
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
if (rootvp->v_usecount > 2) {
vrele(rootvp);
return (EBUSY);
}
error = vflush(mp, rootvp, flags);
if (error)
return (error);
devfs_purge(fmp->dm_rootdir);
vput(rootvp);
vrele(rootvp);
vgone(rootvp);
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 proc *p;
struct vnode *vp;
struct devfs_mount *dmp;
p = curproc; /* XXX */
dmp = VFSTODEVFS(mp);
error = devfs_allocv(dmp->dm_rootdir, mp, &vp, p);
if (error)
return (error);
vp->v_flag |= VROOT;
*vpp = vp;
return (0);
}
static int
devfs_statfs(mp, sbp, p)
struct mount *mp;
struct statfs *sbp;
struct proc *p;
{
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 = {
devfs_mount,
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,
};
VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC);