sys/ufs/mfs/mfs_miniroot.c

   1 /*      $NetBSD: mfs_miniroot.c,v 1.1 2010/03/02 17:20:02 pooka Exp $   */
   2
   3 /*
   4  * Copyright (c) 1989, 1990, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)mfs_vfsops.c        8.11 (Berkeley) 6/19/95
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __KERNEL_RCSID(0, "$NetBSD: mfs_miniroot.c,v 1.1 2010/03/02 17:20:02 pooka Exp $");
  36
  37 #include <sys/param.h>
  38
  39 #include <ufs/mfs/mfs_extern.h>
  40 #include <ufs/ffs/fs.h>
  41
  42 void *  mfs_rootbase;   /* address of mini-root in kernel virtual memory */
  43 u_long  mfs_rootsize;   /* size of mini-root in bytes */
  44
  45 /*
  46  * This is called early in boot to set the base address and size
  47  * of the mini-root.
  48  */
  49 int
  50 mfs_initminiroot(void *base)
  51 {
  52         struct fs *fs = (struct fs *)((char *)base + SBLOCK_UFS1);
  53         static bool inited = false;
  54
  55         if (inited)
  56                 panic("mfs_initminiroot() called more than once");
  57         inited = true;
  58
  59         /* check for valid super block */
  60         if (fs->fs_magic != FS_UFS1_MAGIC || fs->fs_bsize > MAXBSIZE ||
  61             fs->fs_bsize < sizeof(struct fs))
  62                 return (0);
  63         rootfstype = MOUNT_MFS;
  64         mfs_rootbase = base;
  65         mfs_rootsize = fs->fs_fsize * fs->fs_size;
  66         rootdev = makedev(255, 0);
  67         return (mfs_rootsize);
  68 }