freebsd-dev/sys/fs/portalfs/portal_vfsops.c
2012-03-13 10:04:13 +00:00

264 lines
6.6 KiB
C

/*-
* 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.
* 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 8.11 (Berkeley) 5/14/95
*
* $FreeBSD$
*/
/*
* Portal Filesystem
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/capability.h>
#include <sys/domain.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/malloc.h>
#include <sys/file.h> /* Must come after sys/malloc.h */
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/vnode.h>
#include <fs/portalfs/portal.h>
static MALLOC_DEFINE(M_PORTALFSMNT, "portal_mount", "PORTAL mount structure");
static vfs_unmount_t portal_unmount;
static vfs_root_t portal_root;
static vfs_statfs_t portal_statfs;
static const char *portal_opts[] = {
"socket", "config",
NULL
};
static int
portal_cmount(struct mntarg *ma, void *data, uint64_t flags)
{
struct portal_args args;
int error;
if (data == NULL)
return (EINVAL);
error = copyin(data, &args, sizeof args);
if (error)
return (error);
ma = mount_argf(ma, "socket", "%d", args.pa_socket);
ma = mount_argsu(ma, "config", args.pa_config, MAXPATHLEN);
error = kernel_mount(ma, flags);
return (error);
}
/*
* Mount the per-process file descriptors (/dev/fd)
*/
static int
portal_mount(struct mount *mp)
{
struct file *fp;
struct portalmount *fmp;
struct socket *so;
struct vnode *rvp;
struct thread *td;
struct portalnode *pn;
int error, v;
char *p;
td = curthread;
if (vfs_filteropt(mp->mnt_optnew, portal_opts))
return (EINVAL);
error = vfs_scanopt(mp->mnt_optnew, "socket", "%d", &v);
if (error != 1)
return (EINVAL);
error = vfs_getopt(mp->mnt_optnew, "config", (void **)&p, NULL);
if (error)
return (error);
/*
* Capsicum is not incompatible with portalfs, but we don't really
* know what rights are required. In the spirit of "better safe than
* sorry", pretend that all rights are required for now.
*/
if ((error = fget(td, v, CAP_MASK_VALID, &fp)) != 0)
return (error);
if (fp->f_type != DTYPE_SOCKET) {
fdrop(fp, td);
return(ENOTSOCK);
}
so = fp->f_data; /* XXX race against userland */
if (so->so_proto->pr_domain->dom_family != AF_UNIX) {
fdrop(fp, td);
return (ESOCKTNOSUPPORT);
}
pn = malloc(sizeof(struct portalnode),
M_TEMP, M_WAITOK);
fmp = malloc(sizeof(struct portalmount),
M_PORTALFSMNT, M_WAITOK); /* XXX */
error = getnewvnode("portal", mp, &portal_vnodeops, &rvp); /* XXX */
if (error) {
free(fmp, M_PORTALFSMNT);
free(pn, M_TEMP);
fdrop(fp, td);
return (error);
}
error = insmntque(rvp, mp); /* XXX: Too early for mpsafe fs */
if (error != 0) {
free(fmp, M_PORTALFSMNT);
free(pn, M_TEMP);
fdrop(fp, td);
return (error);
}
rvp->v_data = pn;
rvp->v_type = VDIR;
rvp->v_vflag |= VV_ROOT;
VTOPORTAL(rvp)->pt_arg = 0;
VTOPORTAL(rvp)->pt_size = 0;
VTOPORTAL(rvp)->pt_fileid = PORTAL_ROOTFILEID;
fmp->pm_root = rvp;
fhold(fp);
fmp->pm_server = fp;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_LOCAL;
MNT_IUNLOCK(mp);
mp->mnt_data = fmp;
vfs_getnewfsid(mp);
vfs_mountedfrom(mp, p);
fdrop(fp, td);
return (0);
}
static int
portal_unmount(mp, mntflags)
struct mount *mp;
int mntflags;
{
int error, flags = 0;
if (mntflags & MNT_FORCE)
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
/* There is 1 extra root vnode reference (pm_root). */
error = vflush(mp, 1, flags, curthread);
if (error)
return (error);
/*
* 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(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 thread *) 0);
/*
* Finally, throw away the portalmount structure
*/
free(mp->mnt_data, M_PORTALFSMNT); /* XXX */
mp->mnt_data = NULL;
return (0);
}
static int
portal_root(mp, flags, vpp)
struct mount *mp;
int flags;
struct vnode **vpp;
{
struct vnode *vp;
/*
* Return locked reference to root.
*/
vp = VFSTOPORTAL(mp)->pm_root;
VREF(vp);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
*vpp = vp;
return (0);
}
static int
portal_statfs(mp, sbp)
struct mount *mp;
struct statfs *sbp;
{
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 */
return (0);
}
static struct vfsops portal_vfsops = {
.vfs_cmount = portal_cmount,
.vfs_mount = portal_mount,
.vfs_root = portal_root,
.vfs_statfs = portal_statfs,
.vfs_unmount = portal_unmount,
};
VFS_SET(portal_vfsops, portalfs, VFCF_SYNTHETIC);