vfs_mount.c revision 34479 
1/*
2 * Copyright (c) 1989, 1993, 1995
3 *	The Regents of the University of California.  All rights reserved.
4 * Copyright (c) 1995 Artisoft, Inc.  All Rights Reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *	This product includes software developed by the University of
17 *	California, Berkeley and its contributors.
18 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	@(#)vfs_conf.c	8.8 (Berkeley) 3/31/94
35 * $Id: vfs_conf.c,v 1.21 1998/02/09 06:09:32 eivind Exp $
36 */
37
38/*
39 * PURPOSE:	This file abstracts the root mounting interface from
40 *		the per file system semantics for handling mounts,
41 *		the overall intent of which is to move the BSD
42 *		internals dependence out of the FS code, both to
43 *		make the FS code more portable and to free up some
44 *		of the BSD internals so that they may more easily
45 *		be changed.
46 *
47 * NOTE1:	Code is single entry/single exit to aid debugging
48 *		and conversion for kernel multithreading.
49 *
50 * NOTE2:	Code notes lock state in headers on entry and exit
51 *		as an aid to conversion for kernel multithreading
52 *		on SMP reentrancy
53 */
54#include "opt_bootp.h"
55
56#include <sys/param.h>		/* dev_t (types.h)*/
57#include <sys/kernel.h>
58#include <sys/systm.h>		/* rootvp*/
59#include <sys/proc.h>		/* curproc*/
60#include <sys/vnode.h>		/* NULLVP*/
61#include <sys/mount.h>		/* struct mount*/
62#include <sys/malloc.h>		/* M_MOUNT*/
63
64/*
65 * GLOBALS
66 */
67
68MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount struct");
69
70/*
71 *  These define the root filesystem, device, and root filesystem type.
72 */
73static struct mount *rootfs;
74struct vnode *rootvnode;
75char *mountrootfsname;
76#ifdef BOOTP
77extern void bootpc_init __P((void));
78#endif
79
80/*
81 * vfs_init() will set maxvfsconf
82 * to the highest defined type number.
83 */
84int maxvfsconf;
85struct vfsconf *vfsconf;
86
87/*
88 * Common root mount code shared by all filesystems
89 */
90#define ROOTNAME	"root_device"
91
92/*
93 * vfs_mountrootfs
94 *
95 * Common entry point for root mounts
96 *
97 * PARAMETERS:
98 * 		NONE
99 *
100 * RETURNS:	0	Success
101 *		!0	error number (errno.h)
102 *
103 * LOCK STATE:
104 *		ENTRY
105 *			<no locks held>
106 *		EXIT
107 *			<no locks held>
108 *
109 * NOTES:
110 *		This code is currently supported only for use for
111 *		the FFS file system type.  This is a matter of
112 *		fixing the other file systems, not this code!
113 */
114static void
115vfs_mountrootfs(void *unused)
116{
117	struct mount		*mp;
118	int			err = 0;
119	struct proc		*p = curproc;	/* XXX */
120
121#ifdef BOOTP
122	bootpc_init();
123#endif
124	/*
125	 *  New root mount structure
126	 */
127	if ((err = vfs_rootmountalloc(mountrootfsname, ROOTNAME, &mp))) {
128		printf("error %d: ", err);
129		panic("cannot mount root\n");
130		return ;
131	}
132	mp->mnt_flag		|= MNT_ROOTFS;
133
134	/*
135	 * Attempt the mount
136	 */
137	err = VFS_MOUNT(mp, NULL, NULL, NULL, p);
138	/*
139	 * rootdev may be bogus (slice field may be incorrect for disks)
140	 * If slice field is nonzero, clear and retry.
141	 *
142	 * XXX Implicit knowledge of device minor number layout.
143	 *     This is placeholder code until saner root mounts arrive with
144	 *     DEVFS.
145	 */
146	if ((err == ENXIO) && (rootdev & 0xff0000)) {
147		rootdev &= ~0xff0000;
148		err = VFS_MOUNT(mp, NULL, NULL, NULL, p);
149	}
150	if (err) {
151		vfs_unbusy(mp, p);
152		/*
153		 * free mount struct before failing
154		 * (hardly worthwhile with the PANIC eh?)
155		 */
156		free( mp, M_MOUNT);
157		printf("error %d: ", err);
158		panic("cannot mount root (2)\n");
159		return;
160	}
161
162	simple_lock(&mountlist_slock);
163
164	/*
165	 * Add fs to list of mounted file systems
166	 */
167	CIRCLEQ_INSERT_HEAD(&mountlist, mp, mnt_list);
168
169	simple_unlock(&mountlist_slock);
170	vfs_unbusy(mp, p);
171
172	/* root mount, update system time from FS specific data*/
173	inittodr(mp->mnt_time);
174	return;
175}
176
177SYSINIT(mountroot, SI_SUB_MOUNT_ROOT, SI_ORDER_FIRST, vfs_mountrootfs, NULL)
178
179