xref: /netbsd-src/sys/miscfs/kernfs/kernfs_vfsops.c (revision c0179c282a5968435315a82f4128c61372c68fc3)
1 /*	$NetBSD: kernfs_vfsops.c,v 1.74 2006/11/16 01:33:38 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software donated to Berkeley by
8  * Jan-Simon Pendry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. 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  *	@(#)kernfs_vfsops.c	8.10 (Berkeley) 5/14/95
35  */
36 
37 /*
38  * Kernel params Filesystem
39  */
40 
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: kernfs_vfsops.c,v 1.74 2006/11/16 01:33:38 christos Exp $");
43 
44 #ifdef _KERNEL_OPT
45 #include "opt_compat_netbsd.h"
46 #endif
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/sysctl.h>
51 #include <sys/conf.h>
52 #include <sys/proc.h>
53 #include <sys/vnode.h>
54 #include <sys/mount.h>
55 #include <sys/namei.h>
56 #include <sys/dirent.h>
57 #include <sys/malloc.h>
58 #include <sys/syslog.h>
59 #include <sys/kauth.h>
60 
61 #include <miscfs/specfs/specdev.h>
62 #include <miscfs/kernfs/kernfs.h>
63 
64 MALLOC_DEFINE(M_KERNFSMNT, "kernfs mount", "kernfs mount structures");
65 
66 dev_t rrootdev = NODEV;
67 
68 void	kernfs_init(void);
69 void	kernfs_reinit(void);
70 void	kernfs_done(void);
71 void	kernfs_get_rrootdev(void);
72 int	kernfs_mount(struct mount *, const char *, void *,
73 	    struct nameidata *, struct lwp *);
74 int	kernfs_start(struct mount *, int, struct lwp *);
75 int	kernfs_unmount(struct mount *, int, struct lwp *);
76 int	kernfs_statvfs(struct mount *, struct statvfs *, struct lwp *);
77 int	kernfs_quotactl(struct mount *, int, uid_t, void *,
78 			     struct lwp *);
79 int	kernfs_sync(struct mount *, int, kauth_cred_t, struct lwp *);
80 int	kernfs_vget(struct mount *, ino_t, struct vnode **);
81 
82 void
83 kernfs_init()
84 {
85 #ifdef _LKM
86 	malloc_type_attach(M_KERNFSMNT);
87 #endif
88 	kernfs_hashinit();
89 }
90 
91 void
92 kernfs_reinit()
93 {
94 	kernfs_hashreinit();
95 }
96 
97 void
98 kernfs_done()
99 {
100 #ifdef _LKM
101 	malloc_type_detach(M_KERNFSMNT);
102 #endif
103 	kernfs_hashdone();
104 }
105 
106 void
107 kernfs_get_rrootdev()
108 {
109 	static int tried = 0;
110 
111 	if (tried) {
112 		/* Already did it once. */
113 		return;
114 	}
115 	tried = 1;
116 
117 	if (rootdev == NODEV)
118 		return;
119 	rrootdev = devsw_blk2chr(rootdev);
120 	if (rrootdev != NODEV)
121 		return;
122 	rrootdev = NODEV;
123 	printf("kernfs_get_rrootdev: no raw root device\n");
124 }
125 
126 /*
127  * Mount the Kernel params filesystem
128  */
129 int
130 kernfs_mount(struct mount *mp, const char *path, void *data,
131     struct nameidata *ndp, struct lwp *l)
132 {
133 	int error = 0;
134 	struct kernfs_mount *fmp;
135 
136 	if (UIO_MX & (UIO_MX - 1)) {
137 		log(LOG_ERR, "kernfs: invalid directory entry size");
138 		return (EINVAL);
139 	}
140 
141 	if (mp->mnt_flag & MNT_GETARGS)
142 		return 0;
143 	/*
144 	 * Update is a no-op
145 	 */
146 	if (mp->mnt_flag & MNT_UPDATE)
147 		return (EOPNOTSUPP);
148 
149 	MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
150 	    M_KERNFSMNT, M_WAITOK);
151 	memset(fmp, 0, sizeof(*fmp));
152 	TAILQ_INIT(&fmp->nodelist);
153 
154 	mp->mnt_stat.f_namemax = MAXNAMLEN;
155 	mp->mnt_flag |= MNT_LOCAL;
156 	mp->mnt_data = fmp;
157 	vfs_getnewfsid(mp);
158 
159 	if ((error = set_statvfs_info(path, UIO_USERSPACE, "kernfs",
160 	    UIO_SYSSPACE, mp, l)) != 0) {
161 		free(fmp, M_KERNFSMNT);
162 		return error;
163 	}
164 
165 	kernfs_get_rrootdev();
166 	return 0;
167 }
168 
169 int
170 kernfs_start(struct mount *mp, int flags,
171     struct lwp *l)
172 {
173 
174 	return (0);
175 }
176 
177 int
178 kernfs_unmount(struct mount *mp, int mntflags, struct lwp *l)
179 {
180 	int error;
181 	int flags = 0;
182 
183 	if (mntflags & MNT_FORCE)
184 		flags |= FORCECLOSE;
185 
186 	if ((error = vflush(mp, 0, flags)) != 0)
187 		return (error);
188 
189 	/*
190 	 * Finally, throw away the kernfs_mount structure
191 	 */
192 	free(mp->mnt_data, M_KERNFSMNT);
193 	mp->mnt_data = NULL;
194 	return (0);
195 }
196 
197 int
198 kernfs_root(mp, vpp)
199 	struct mount *mp;
200 	struct vnode **vpp;
201 {
202 
203 	/* setup "." */
204 	return (kernfs_allocvp(mp, vpp, KFSkern, &kern_targets[0], 0));
205 }
206 
207 int
208 kernfs_quotactl(struct mount *mp, int cmd, uid_t uid,
209     void *arg, struct lwp *l)
210 {
211 
212 	return (EOPNOTSUPP);
213 }
214 
215 int
216 kernfs_statvfs(struct mount *mp, struct statvfs *sbp, struct lwp *l)
217 {
218 
219 	sbp->f_bsize = DEV_BSIZE;
220 	sbp->f_frsize = DEV_BSIZE;
221 	sbp->f_iosize = DEV_BSIZE;
222 	sbp->f_blocks = 2;		/* 1K to keep df happy */
223 	sbp->f_bfree = 0;
224 	sbp->f_bavail = 0;
225 	sbp->f_bresvd = 0;
226 	sbp->f_files = 1024;	/* XXX lie */
227 	sbp->f_ffree = 128;	/* XXX lie */
228 	sbp->f_favail = 128;	/* XXX lie */
229 	sbp->f_fresvd = 0;
230 	copy_statvfs_info(sbp, mp);
231 	return (0);
232 }
233 
234 /*ARGSUSED*/
235 int
236 kernfs_sync(struct mount *mp, int waitfor,
237     kauth_cred_t uc, struct lwp *l)
238 {
239 
240 	return (0);
241 }
242 
243 /*
244  * Kernfs flat namespace lookup.
245  * Currently unsupported.
246  */
247 int
248 kernfs_vget(struct mount *mp, ino_t ino,
249     struct vnode **vpp)
250 {
251 
252 	return (EOPNOTSUPP);
253 }
254 
255 SYSCTL_SETUP(sysctl_vfs_kernfs_setup, "sysctl vfs.kern subtree setup")
256 {
257 
258 	sysctl_createv(clog, 0, NULL, NULL,
259 		       CTLFLAG_PERMANENT,
260 		       CTLTYPE_NODE, "vfs", NULL,
261 		       NULL, 0, NULL, 0,
262 		       CTL_VFS, CTL_EOL);
263 	sysctl_createv(clog, 0, NULL, NULL,
264 		       CTLFLAG_PERMANENT,
265 		       CTLTYPE_NODE, "kernfs",
266 		       SYSCTL_DESCR("/kern file system"),
267 		       NULL, 0, NULL, 0,
268 		       CTL_VFS, 11, CTL_EOL);
269 	/*
270 	 * XXX the "11" above could be dynamic, thereby eliminating one
271 	 * more instance of the "number to vfs" mapping problem, but
272 	 * "11" is the order as taken from sys/mount.h
273 	 */
274 }
275 
276 extern const struct vnodeopv_desc kernfs_vnodeop_opv_desc;
277 
278 const struct vnodeopv_desc * const kernfs_vnodeopv_descs[] = {
279 	&kernfs_vnodeop_opv_desc,
280 	NULL,
281 };
282 
283 struct vfsops kernfs_vfsops = {
284 	MOUNT_KERNFS,
285 	kernfs_mount,
286 	kernfs_start,
287 	kernfs_unmount,
288 	kernfs_root,
289 	kernfs_quotactl,
290 	kernfs_statvfs,
291 	kernfs_sync,
292 	kernfs_vget,
293 	NULL,				/* vfs_fhtovp */
294 	NULL,				/* vfs_vptofh */
295 	kernfs_init,
296 	kernfs_reinit,
297 	kernfs_done,
298 	NULL,				/* vfs_mountroot */
299 	(int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
300 	vfs_stdextattrctl,
301 	kernfs_vnodeopv_descs,
302 	0,
303 	{ NULL, NULL },
304 };
305 VFS_ATTACH(kernfs_vfsops);
306