xref: /freebsd/sys/fs/pseudofs/pseudofs.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /*-
2  * Copyright (c) 2001 Dag-Erling Co�dan Sm�rgrav
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
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. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  *	$FreeBSD$
29  */
30 
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/module.h>
36 #include <sys/mount.h>
37 #include <sys/mutex.h>
38 #include <sys/proc.h>
39 #include <sys/sbuf.h>
40 #include <sys/sysctl.h>
41 #include <sys/vnode.h>
42 
43 #include <fs/pseudofs/pseudofs.h>
44 #include <fs/pseudofs/pseudofs_internal.h>
45 
46 SYSCTL_NODE(_vfs, OID_AUTO, pfs, CTLFLAG_RW, 0,
47     "pseudofs");
48 
49 /*
50  * Mount a pseudofs instance
51  */
52 int
53 pfs_mount(struct pfs_info *pi, struct mount *mp, char *path, caddr_t data,
54 	  struct nameidata *ndp, struct proc *p)
55 {
56 	struct statfs *sbp;
57 
58 	if (mp->mnt_flag & MNT_UPDATE)
59 		return (EOPNOTSUPP);
60 
61 	mp->mnt_flag |= MNT_LOCAL;
62 	mp->mnt_data = (qaddr_t)pi;
63 	vfs_getnewfsid(mp);
64 
65 	sbp = &mp->mnt_stat;
66 	bcopy(pi->pi_name, sbp->f_mntfromname, sizeof pi->pi_name);
67 	sbp->f_bsize = PAGE_SIZE;
68 	sbp->f_iosize = PAGE_SIZE;
69 	sbp->f_blocks = 1;
70 	sbp->f_bfree = 0;
71 	sbp->f_bavail = 0;
72 	sbp->f_files = 1;
73 	sbp->f_ffree = 0;
74 
75 	return (0);
76 }
77 
78 /*
79  * Unmount a pseudofs instance
80  */
81 int
82 pfs_unmount(struct mount *mp, int mntflags, struct proc *p)
83 {
84 	struct pfs_info *pi;
85 	int error;
86 
87 	pi = (struct pfs_info *)mp->mnt_data;
88 
89 	/* XXX do stuff with pi... */
90 
91 	error = vflush(mp, 0, (mntflags & MNT_FORCE) ?  FORCECLOSE : 0);
92 	return (error);
93 }
94 
95 /*
96  * Return a root vnode
97  */
98 int
99 pfs_root(struct mount *mp, struct vnode **vpp)
100 {
101 	struct pfs_info *pi;
102 
103 	pi = (struct pfs_info *)mp->mnt_data;
104 	return pfs_vncache_alloc(mp, vpp, pi->pi_root, NO_PID);
105 }
106 
107 /*
108  * Return filesystem stats
109  */
110 int
111 pfs_statfs(struct mount *mp, struct statfs *sbp, struct proc *p)
112 {
113 	bcopy(&mp->mnt_stat, sbp, sizeof *sbp);
114 	return (0);
115 }
116 
117 /*
118  * Initialize a pseudofs instance
119  */
120 int
121 pfs_init(struct pfs_info *pi, struct vfsconf *vfc)
122 {
123 	mtx_init(&pi->pi_mutex, "pseudofs", MTX_DEF);
124 	pfs_fileno_init(pi);
125 	printf("%s registered\n", pi->pi_name);
126 	return (0);
127 }
128 
129 /*
130  * Destroy a pseudofs instance
131  */
132 int
133 pfs_uninit(struct pfs_info *pi, struct vfsconf *vfc)
134 {
135 	pfs_fileno_uninit(pi);
136 	mtx_destroy(&pi->pi_mutex);
137 	printf("%s unregistered\n", pi->pi_name);
138 	return (0);
139 }
140 
141 /*
142  * Handle load / unload events
143  */
144 static int
145 pfs_modevent(module_t mod, int evt, void *arg)
146 {
147 	switch (evt) {
148 	case MOD_LOAD:
149 		pfs_fileno_load();
150 		pfs_vncache_load();
151 		break;
152 	case MOD_UNLOAD:
153 	case MOD_SHUTDOWN:
154 		pfs_vncache_unload();
155 		pfs_fileno_unload();
156 		break;
157 	default:
158 		printf("pseudofs: unexpected event type %d\n", evt);
159 		break;
160 	}
161 	return 0;
162 }
163 
164 /*
165  * Module declaration
166  */
167 static moduledata_t pseudofs_data = {
168 	"pseudofs",
169 	pfs_modevent,
170 	NULL
171 };
172 DECLARE_MODULE(pseudofs, pseudofs_data, SI_SUB_EXEC, SI_ORDER_FIRST);
173 MODULE_VERSION(pseudofs, 1);
174