vfs_mount.c revision 12569 
1/*
2 * Copyright (c) 1989, 1993
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 1.10 1995/10/29 15:31:25 phk 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 <sys/param.h>		/* dev_t (types.h)*/
55#include <sys/systm.h>		/* rootvp*/
56#include <sys/proc.h>		/* curproc*/
57#include <sys/vnode.h>		/* NULLVP*/
58#include <sys/mount.h>		/* struct mount*/
59#include <sys/malloc.h>		/* M_MOUNT*/
60
61/*
62 * GLOBALS
63 */
64int (*mountroot) __P((void *));
65struct vnode *rootvnode;
66struct vfsops	*mountrootvfsops;
67
68
69/*
70 * Common root mount code shared by all filesystems
71 */
72#define ROOTDIR		"/"
73#define ROOTNAME	"root_device"
74
75
76
77/*
78 * vfs_mountroot
79 *
80 * Common entry point for root mounts
81 *
82 * PARAMETERS:
83 *		data	pointer to the vfs_ops for the FS type mounting
84 *
85 * RETURNS:	0	Success
86 *		!0	error number (errno.h)
87 *
88 * LOCK STATE:
89 *		ENTRY
90 *			<no locks held>
91 *		EXIT
92 *			<no locks held>
93 *
94 * NOTES:
95 *		This code is currently supported only for use for
96 *		the FFS file system type.  This is a matter of
97 *		fixing the other file systems, not this code!
98 */
99int
100vfs_mountroot(data)
101	void			*data;
102{
103	struct mount		*mp;
104	u_int			size;
105	int			err = 0;
106	struct proc		*p = curproc;	/* XXX */
107	struct vfsops		*mnt_op = (struct vfsops *)data;
108
109	/*
110	 *  New root mount structure
111	 */
112	mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
113	bzero((char *)mp, (u_long)sizeof(struct mount));
114	mp->mnt_op		= mnt_op;
115	mp->mnt_flag		= MNT_ROOTFS;
116	mp->mnt_vnodecovered	= NULLVP;
117
118	/*
119	 * Lock mount point
120	 */
121	if( ( err = vfs_lock(mp)) != 0)
122		goto error_1;
123
124	/* Save "last mounted on" info for mount point (NULL pad)*/
125	copystr(	ROOTDIR,			/* mount point*/
126			mp->mnt_stat.f_mntonname,	/* save area*/
127			MNAMELEN - 1,			/* max size*/
128			&size);				/* real size*/
129	bzero( mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
130
131	/* Save "mounted from" info for mount point (NULL pad)*/
132	copystr(	ROOTNAME,			/* device name*/
133			mp->mnt_stat.f_mntfromname,	/* save area*/
134			MNAMELEN - 1,			/* max size*/
135			&size);				/* real size*/
136	bzero( mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
137
138	/*
139	 * Attempt the mount
140	 */
141	err = VFS_MOUNT( mp, NULL, NULL, NULL, p);
142	if( err)
143		goto error_2;
144
145	/* Add fs to list of mounted file systems*/
146	CIRCLEQ_INSERT_TAIL( &mountlist, mp, mnt_list);
147
148	/* Unlock mount point*/
149	vfs_unlock(mp);
150
151	/* root mount, update system time from FS specific data*/
152	inittodr( mp->mnt_time);
153
154	goto success;
155
156
157error_2:	/* mount error*/
158
159	/* unlock before failing*/
160	vfs_unlock( mp);
161
162error_1:	/* lock error*/
163
164	/* free mount struct before failing*/
165	free( mp, M_MOUNT);
166
167success:
168	return( err);
169}
170