--- /dev/null
+/* $OpenBSD: union_lkm.c,v 1.1 1997/01/20 09:15:32 mickey Exp $ */
+
+/*
+ * union_lkm.c (was: kernfsmod.c)
+ *
+ * 05 Jun 93 Terry Lambert Original
+ * 20 Jan 97 Michael Shalayeff NetBSD PR
+ * by Paul Goyette <paul@pgoyette.bdt.com>
+ *
+ * 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.
+ *
+ * from Id: kernfsmod.c,v 1.1.1.1 1995/10/18 08:44:22 deraadt Exp
+ */
+#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>
+#include <sys/namei.h>
+
+/*
+ * This is the vfsops table from /sys/miscfs/union/union_vfsops.c
+ */
+extern struct vfsops union_vfsops;
+extern struct vnodeopv_desc union_vnodeop_opv_desc;
+
+extern int (*union_check_p) __P((off_t, struct proc *, struct vnode *,
+ struct file *, struct uio, int *));
+extern int union_check __P((off_t, struct proc *, struct vnode *,
+ struct file *, struct uio, int *));
+static int union_load __P((struct lkm_table *, int));
+
+/*
+ * declare the filesystem
+ */
+MOD_VFS("union", -1, &union_vfsops)
+
+/*
+ * Routine to execute when module is loaded or unloaded. We need to set
+ * a couple of critical pointers for the vfs_syscalls routines.
+ */
+static int
+union_load(lkmtp, cmd)
+ struct lkm_table *lkmtp;
+ int cmd;
+{
+ switch (cmd) {
+ case LKM_E_LOAD:
+ union_check_p = union_check;
+ break;
+
+ case LKM_E_UNLOAD:
+ union_check_p = NULL;
+ break;
+ };
+ return (0);
+}
+
+/*
+ * LKM entry point
+ * (named this way to avoid keyword collision)
+ */
+int
+unionfs(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(&union_vnodeop_opv_desc);
+ vfs_opv_init_default(&union_vnodeop_opv_desc);
+
+ DISPATCH(lkmtp, cmd, ver, union_load, union_load, lkm_nofunc)
+}
+
+