freebsd-src/sys/kern/vfs_conf.c
Mike Smith 617dd81f70 If the root mount fails from a device that is not the compatability slice
of a disk, because that slice does not exist, try again mounting from the
compatability slice.

This handles the case where a disk has been initialised by 'disklabel
auto', which places a bogus and invalid slice entry on the disk.
The bootstrap is not smart enough to reject this slice, and pretends to
boot from it.  Believing the the bootstrap at this point is unwise.

Booting from non-'wd' disks thus prepared is still broken, as
'disklabel -rwB xdN auto' does not initialise the disk type field, and
the bootstrap mistakenly claims that the disk is handled by 'wd'.

Behaviour is now consistent with DEVFS expected characteristics.
1998-03-11 00:10:31 +00:00

179 lines
5.1 KiB
C

/*
* Copyright (c) 1989, 1993, 1995
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1995 Artisoft, Inc. 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 the University of
* California, Berkeley and its contributors.
* 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.
*
* @(#)vfs_conf.c 8.8 (Berkeley) 3/31/94
* $Id: vfs_conf.c,v 1.21 1998/02/09 06:09:32 eivind Exp $
*/
/*
* PURPOSE: This file abstracts the root mounting interface from
* the per file system semantics for handling mounts,
* the overall intent of which is to move the BSD
* internals dependence out of the FS code, both to
* make the FS code more portable and to free up some
* of the BSD internals so that they may more easily
* be changed.
*
* NOTE1: Code is single entry/single exit to aid debugging
* and conversion for kernel multithreading.
*
* NOTE2: Code notes lock state in headers on entry and exit
* as an aid to conversion for kernel multithreading
* on SMP reentrancy
*/
#include "opt_bootp.h"
#include <sys/param.h> /* dev_t (types.h)*/
#include <sys/kernel.h>
#include <sys/systm.h> /* rootvp*/
#include <sys/proc.h> /* curproc*/
#include <sys/vnode.h> /* NULLVP*/
#include <sys/mount.h> /* struct mount*/
#include <sys/malloc.h> /* M_MOUNT*/
/*
* GLOBALS
*/
MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount struct");
/*
* These define the root filesystem, device, and root filesystem type.
*/
static struct mount *rootfs;
struct vnode *rootvnode;
char *mountrootfsname;
#ifdef BOOTP
extern void bootpc_init __P((void));
#endif
/*
* vfs_init() will set maxvfsconf
* to the highest defined type number.
*/
int maxvfsconf;
struct vfsconf *vfsconf;
/*
* Common root mount code shared by all filesystems
*/
#define ROOTNAME "root_device"
/*
* vfs_mountrootfs
*
* Common entry point for root mounts
*
* PARAMETERS:
* NONE
*
* RETURNS: 0 Success
* !0 error number (errno.h)
*
* LOCK STATE:
* ENTRY
* <no locks held>
* EXIT
* <no locks held>
*
* NOTES:
* This code is currently supported only for use for
* the FFS file system type. This is a matter of
* fixing the other file systems, not this code!
*/
static void
vfs_mountrootfs(void *unused)
{
struct mount *mp;
int err = 0;
struct proc *p = curproc; /* XXX */
#ifdef BOOTP
bootpc_init();
#endif
/*
* New root mount structure
*/
if ((err = vfs_rootmountalloc(mountrootfsname, ROOTNAME, &mp))) {
printf("error %d: ", err);
panic("cannot mount root\n");
return ;
}
mp->mnt_flag |= MNT_ROOTFS;
/*
* Attempt the mount
*/
err = VFS_MOUNT(mp, NULL, NULL, NULL, p);
/*
* rootdev may be bogus (slice field may be incorrect for disks)
* If slice field is nonzero, clear and retry.
*
* XXX Implicit knowledge of device minor number layout.
* This is placeholder code until saner root mounts arrive with
* DEVFS.
*/
if ((err == ENXIO) && (rootdev & 0xff0000)) {
rootdev &= ~0xff0000;
err = VFS_MOUNT(mp, NULL, NULL, NULL, p);
}
if (err) {
vfs_unbusy(mp, p);
/*
* free mount struct before failing
* (hardly worthwhile with the PANIC eh?)
*/
free( mp, M_MOUNT);
printf("error %d: ", err);
panic("cannot mount root (2)\n");
return;
}
simple_lock(&mountlist_slock);
/*
* Add fs to list of mounted file systems
*/
CIRCLEQ_INSERT_HEAD(&mountlist, mp, mnt_list);
simple_unlock(&mountlist_slock);
vfs_unbusy(mp, p);
/* root mount, update system time from FS specific data*/
inittodr(mp->mnt_time);
return;
}
SYSINIT(mountroot, SI_SUB_MOUNT_ROOT, SI_ORDER_FIRST, vfs_mountrootfs, NULL)