xref: /freebsd/sys/kern/vfs_mount.c (revision 0ea3482342b4d7d6e71f3007ce4dafe445c639fd)
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 1.9 1995/09/09 18:10:15 davidg 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  */
64 int (*mountroot) __P((void *));
65 struct vnode *rootvnode;
66 struct 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  */
99 int
100 vfs_mountroot(data)
101 	void *data;	/* file system function table*/
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 
157 error_2:	/* mount error*/
158 
159 	/* unlock before failing*/
160 	vfs_unlock( mp);
161 
162 error_1:	/* lock error*/
163 
164 	/* free mount struct before failing*/
165 	free( mp, M_MOUNT);
166 
167 success:
168 	return( err);
169 }
170 
171 
172 /*
173  * EOF -- This file has not been truncated.
174  */
175