NetBSD/sys/kern/vfs_hooks.c

116 lines
3.7 KiB
C

/* $NetBSD: vfs_hooks.c,v 1.2 2005/12/11 12:24:30 christos Exp $ */
/*-
* Copyright (c) 2005 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Julio M. Merino Vidal.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* VFS hooks.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: vfs_hooks.c,v 1.2 2005/12/11 12:24:30 christos Exp $");
#include <sys/param.h>
#include <sys/mount.h>
/*
* Static list of file system specific hook sets supported by the kernel.
*/
__link_set_decl(vfs_hooks, struct vfs_hooks);
/*
* Initialize a VFS hook set that does nothing. This is to ensure that
* we have, at the very least, one item in the link set. Otherwise,
* ld(1) will complain.
*/
static struct vfs_hooks null_hooks = {
NULL /* vh_unmount */
};
VFS_HOOKS_ATTACH(null_hooks);
/*
* Macro to be used in one of the vfs_hooks_* function for hooks that
* return an error code. Calls will stop as soon as one of the hooks
* fails.
*/
#define VFS_HOOKS_W_ERROR(func, args) \
int error; \
struct vfs_hooks * const *hp; \
\
error = 0; \
\
__link_set_foreach(hp, vfs_hooks) { \
if ((*hp)-> func != NULL) { \
error = (*hp)-> func args; \
if (error != 0) \
break; \
} \
} \
\
return error;
/*
* Macro to be used in one of the vfs_hooks_* function for hooks that
* do not return any error code. All hooks will be executed
* unconditionally.
*/
#define VFS_HOOKS_WO_ERROR(func, fargs, hook, hargs) \
void \
func fargs \
{ \
struct vfs_hooks * const *hp; \
\
__link_set_foreach(hp, vfs_hooks) { \
if ((*hp)-> hook != NULL) \
(*hp)-> hook hargs; \
} \
}
/*
* Routines to iterate over VFS hooks lists and execute them.
*/
VFS_HOOKS_WO_ERROR(vfs_hooks_unmount, (struct mount *mp), vh_unmount, (mp));
/*
void
vfs_hooks_unmount(struct mount *mp)
{
VFS_HOOKS_WO_ERROR(vh_unmount, (mp));
}
*/