NetBSD/share/lkm/vfs/module/kernfsmod.c

/*
 * kernfsmod.c
 *
 * 05 Jun 93	Terry Lambert		Original
 *
 * Copyright (c) 1993 Terrence R. Lambert.
 * All rights reserved.
 *
 * 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 Terrence R. Lambert.
 * 4. The name Terrence R. Lambert may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``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 TERRENCE R. LAMBERT 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.
 *
 *	$Id: kernfsmod.c,v 1.3 1994/07/24 07:16:23 mycroft Exp $
 */
#define printf I_HATE_ANSI
#include <stdio.h>
#undef printf
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/mount.h>
#include <sys/exec.h>
#include <sys/lkm.h>
#include <sys/file.h>
#include <sys/errno.h>

/*
 * This is the vfsops table from /sys/miscfs/kernfs/kernfs_vfsops.c
 */
extern struct vfsops kernfs_vfsops;
extern struct vnodeopv_desc kernfs_vnodeop_opv_desc;

/*
 * Currently, the mount system call is broken in the way it operates
 * and the vfssw[] table does not have a character string identifier
 * for the file system type; therefore, to remount a file system after
 * it has been mounted in the first place, the offset into the table
 * must be the same; this will be corrected in future patches, but
 * not right now.  At the same time the fstab format will need to
 * change to allow definition without mount of file systems.
 *
 * The flags field is a parameter to the init; this could be used to
 * change the file system operation: for instance, in ISOFS, this
 * could be used to enable/disable Rockridge extensions.
 */
MOD_VFS("kernfs", MOUNT_KERNFS, &kernfs_vfsops)

/*
 * External entry point; should generally match name of .o file.  The
 * arguments are always the same for all loaded modules.  The "load",
 * "unload", and "stat" functions in "DISPATCH" will be called under
 * their respective circumstances unless their value is "nosys".  If
 * called, they are called with the same arguments (cmd is included to
 * allow the use of a single function, ver is included for version
 * matching between modules and the kernel loader for the modules).
 *
 * Since we expect to link in the kernel and add external symbols to
 * the kernel symbol name space in a future version, generally all
 * functions used in the implementation of a particular module should
 * be static unless they are expected to be seen in other modules or
 * to resolve unresolved symbols already existing in the kernel (the
 * second case is not likely to ever occur).
 *
 * The entry point should return 0 unless it is refusing load (in which
 * case it should return an errno from errno.h).
 */
kernfsmod(lkmtp, cmd, ver)
	struct lkm_table *lkmtp;	
	int cmd;
	int ver;
{

	/*
	 * This is normally done automatically at boot time if the
	 * opv_desc is listed in vfs_opv_descs[] in vfs_conf.c.  For
	 * loaded modules, we have to do it manually.
	 */
	vfs_opv_init_explicit(&kernfs_vnodeop_opv_desc);
	vfs_opv_init_default(&kernfs_vnodeop_opv_desc);

	DISPATCH(lkmtp, cmd, ver, nosys, nosys, nosys)
}