/*-
* 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 <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/sx.h>
#include <sys/vnode.h>
#include <sys/limits.h>
#include <sys/jail.h>
#include <fs/devfs/devfs.h>
static struct unrhdr *devfs_unr;
MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data");
static vfs_mount_t devfs_mount;
static vfs_unmount_t devfs_unmount;
static vfs_root_t devfs_root;
static vfs_statfs_t devfs_statfs;
static const char *devfs_opts[] = {
"from", "export", "ruleset", NULL
};
/*
* Mount the filesystem
*/
static int
devfs_mount(struct mount *mp)
{
int error;
struct devfs_mount *fmp;
struct vnode *rvp;
struct thread *td = curthread;
int injail, rsnum;
if (devfs_unr == NULL)
devfs_unr = new_unrhdr(0, INT_MAX, NULL);
error = 0;
if (mp->mnt_flag & MNT_ROOTFS)
return (EOPNOTSUPP);
if (!prison_allow(td->td_ucred, PR_ALLOW_MOUNT_DEVFS))
return (EPERM);
rsnum = 0;
injail = jailed(td->td_ucred);
if (mp->mnt_optnew != NULL) {
if (vfs_filteropt(mp->mnt_optnew, devfs_opts))
return (EINVAL);
if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0))
return (EOPNOTSUPP);
if (vfs_getopt(mp->mnt_optnew, "ruleset", NULL, NULL) == 0 &&
(vfs_scanopt(mp->mnt_optnew, "ruleset", "%d",
&rsnum) != 1 || rsnum < 0 || rsnum > 65535)) {
vfs_mount_error(mp, "%s",
"invalid ruleset specification");
return (EINVAL);
}
if (injail && rsnum != 0 &&
rsnum != td->td_ucred->cr_prison->pr_devfs_rsnum)
return (EPERM);
}
/* jails enforce their ruleset */
if (injail)
rsnum = td->td_ucred->cr_prison->pr_devfs_rsnum;
if (mp->mnt_flag & MNT_UPDATE) {
if (rsnum != 0) {
fmp = mp->mnt_data;
if (fmp != NULL) {
sx_xlock(&fmp->dm_lock);
devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
devfs_ruleset_apply(fmp);
sx_xunlock(&fmp->dm_lock);
}
}
return (0);
}
fmp = malloc(sizeof *fmp, M_DEVFS, M_WAITOK | M_ZERO);
fmp->dm_idx = alloc_unr(devfs_unr);
sx_init(&fmp->dm_lock, "devfsmount");
fmp->dm_holdcnt = 1;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED;
#ifdef MAC
mp->mnt_flag |= MNT_MULTILABEL;
#endif
MNT_IUNLOCK(mp);
fmp->dm_mount = mp;
mp->mnt_data = (void *) fmp;
vfs_getnewfsid(mp);
fmp->dm_rootdir = devfs_vmkdir(fmp, NULL, 0, NULL, DEVFS_ROOTINO);
error = devfs_root(mp, LK_EXCLUSIVE, &rvp);
if (error) {
sx_destroy(&fmp->dm_lock);
free_unr(devfs_unr, fmp->dm_idx);
free(fmp, M_DEVFS);
return (error);
}
if (rsnum != 0) {
sx_xlock(&fmp->dm_lock);
devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
sx_xunlock(&fmp->dm_lock);
}
VOP_UNLOCK(rvp, 0);
vfs_mountedfrom(mp, "devfs");
return (0);
}
void
devfs_unmount_final(struct devfs_mount *fmp)
{
sx_destroy(&fmp->dm_lock);
free(fmp, M_DEVFS);
}
static int
devfs_unmount(struct mount *mp, int mntflags)
{
int error;
int flags = 0;
struct devfs_mount *fmp;
int hold;
u_int idx;
fmp = VFSTODEVFS(mp);
KASSERT(fmp->dm_mount != NULL,
("devfs_unmount unmounted devfs_mount"));
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
/* There is 1 extra root vnode reference from devfs_mount(). */
error = vflush(mp, 1, flags, curthread);
if (error)
return (error);
sx_xlock(&fmp->dm_lock);
devfs_cleanup(fmp);
devfs_rules_cleanup(fmp);
fmp->dm_mount = NULL;
hold = --fmp->dm_holdcnt;
mp->mnt_data = NULL;
idx = fmp->dm_idx;
sx_xunlock(&fmp->dm_lock);
free_unr(devfs_unr, idx);
if (hold == 0)
devfs_unmount_final(fmp);
return 0;
}
/* Return locked reference to root. */
static int
devfs_root(struct mount *mp, int flags, struct vnode **vpp)
{
int error;
struct vnode *vp;
struct devfs_mount *dmp;
dmp = VFSTODEVFS(mp);
sx_xlock(&dmp->dm_lock);
error = devfs_allocv(dmp->dm_rootdir, mp, LK_EXCLUSIVE, &vp);
if (error)
return (error);
vp->v_vflag |= VV_ROOT;
*vpp = vp;
return (0);
}
static int
devfs_statfs(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 = 0;
sbp->f_ffree = 0;
return (0);
}
static struct vfsops devfs_vfsops = {
.vfs_mount = devfs_mount,
.vfs_root = devfs_root,
.vfs_statfs = devfs_statfs,
.vfs_unmount = devfs_unmount,
};
VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC | VFCF_JAIL);
