freebsd-skq/sys/nfs/nfs_nfssvc.c
Rick Macklem 5f73287a6e Modify the experimental NFSv4 server so that it posts a SIGUSR2
signal to the master nfsd daemon whenever the stable restart
file has been modified. This will allow the master nfsd daemon
to maintain an up to date backup copy of the file. This is
enabled via the nfssvc() syscall, so that older nfsd daemons
will not be signaled.

Reviewed by:	jhb
MFC after:	1 week
2011-01-14 23:30:35 +00:00

154 lines
4.8 KiB
C

/*-
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_nfs.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/module.h>
#include <sys/sysent.h>
#include <sys/syscall.h>
#include <sys/sysproto.h>
#include <security/audit/audit.h>
#include <nfs/nfssvc.h>
static int nfssvc_offset = SYS_nfssvc;
static struct sysent nfssvc_prev_sysent;
MAKE_SYSENT(nfssvc);
/*
* This tiny module simply handles the nfssvc() system call. The other
* nfs modules that use the system call register themselves by setting
* the nfsd_call_xxx function pointers non-NULL.
*/
int (*nfsd_call_nfsserver)(struct thread *, struct nfssvc_args *) = NULL;
int (*nfsd_call_nfscommon)(struct thread *, struct nfssvc_args *) = NULL;
int (*nfsd_call_nfscl)(struct thread *, struct nfssvc_args *) = NULL;
int (*nfsd_call_nfsd)(struct thread *, struct nfssvc_args *) = NULL;
/*
* Nfs server psuedo system call for the nfsd's
*/
int
nfssvc(struct thread *td, struct nfssvc_args *uap)
{
int error;
KASSERT(!mtx_owned(&Giant), ("nfssvc(): called with Giant"));
AUDIT_ARG_CMD(uap->flag);
error = priv_check(td, PRIV_NFS_DAEMON);
if (error)
return (error);
error = EINVAL;
if ((uap->flag & (NFSSVC_ADDSOCK | NFSSVC_OLDNFSD | NFSSVC_NFSD)) &&
nfsd_call_nfsserver != NULL)
error = (*nfsd_call_nfsserver)(td, uap);
else if ((uap->flag & (NFSSVC_CBADDSOCK | NFSSVC_NFSCBD)) &&
nfsd_call_nfscl != NULL)
error = (*nfsd_call_nfscl)(td, uap);
else if ((uap->flag & (NFSSVC_IDNAME | NFSSVC_GETSTATS |
NFSSVC_GSSDADDPORT | NFSSVC_GSSDADDFIRST | NFSSVC_GSSDDELETEALL |
NFSSVC_NFSUSERDPORT | NFSSVC_NFSUSERDDELPORT)) &&
nfsd_call_nfscommon != NULL)
error = (*nfsd_call_nfscommon)(td, uap);
else if ((uap->flag & (NFSSVC_NFSDNFSD | NFSSVC_NFSDADDSOCK |
NFSSVC_PUBLICFH | NFSSVC_V4ROOTEXPORT | NFSSVC_NOPUBLICFH |
NFSSVC_STABLERESTART | NFSSVC_ADMINREVOKE |
NFSSVC_DUMPCLIENTS | NFSSVC_DUMPLOCKS | NFSSVC_BACKUPSTABLE)) &&
nfsd_call_nfsd != NULL)
error = (*nfsd_call_nfsd)(td, uap);
if (error == EINTR || error == ERESTART)
error = 0;
return (error);
}
/*
* Called once to initialize data structures...
*/
static int
nfssvc_modevent(module_t mod, int type, void *data)
{
static int registered;
int error = 0;
switch (type) {
case MOD_LOAD:
error = syscall_register(&nfssvc_offset, &nfssvc_sysent,
&nfssvc_prev_sysent);
if (error)
break;
registered = 1;
break;
case MOD_UNLOAD:
if (nfsd_call_nfsserver != NULL || nfsd_call_nfscommon != NULL
|| nfsd_call_nfscl != NULL || nfsd_call_nfsd != NULL) {
error = EBUSY;
break;
}
if (registered)
syscall_deregister(&nfssvc_offset, &nfssvc_prev_sysent);
registered = 0;
break;
default:
error = EOPNOTSUPP;
break;
}
return error;
}
static moduledata_t nfssvc_mod = {
"nfssvc",
nfssvc_modevent,
NULL,
};
DECLARE_MODULE(nfssvc, nfssvc_mod, SI_SUB_VFS, SI_ORDER_ANY);
/* So that loader and kldload(2) can find us, wherever we are.. */
MODULE_VERSION(nfssvc, 1);