xref: /netbsd-src/sys/miscfs/kernfs/kernfs_vfsops.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: kernfs_vfsops.c,v 1.71 2006/05/14 21:31:52 elad 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 1.71 2006/05/14 21:31:52 elad 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(mp, path, data, ndp, l)
131 	struct mount *mp;
132 	const char *path;
133 	void *data;
134 	struct nameidata *ndp;
135 	struct lwp *l;
136 {
137 	int error = 0;
138 	struct kernfs_mount *fmp;
139 
140 	if (UIO_MX & (UIO_MX - 1)) {
141 		log(LOG_ERR, "kernfs: invalid directory entry size");
142 		return (EINVAL);
143 	}
144 
145 	if (mp->mnt_flag & MNT_GETARGS)
146 		return 0;
147 	/*
148 	 * Update is a no-op
149 	 */
150 	if (mp->mnt_flag & MNT_UPDATE)
151 		return (EOPNOTSUPP);
152 
153 	MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
154 	    M_KERNFSMNT, M_WAITOK);
155 	memset(fmp, 0, sizeof(*fmp));
156 	TAILQ_INIT(&fmp->nodelist);
157 
158 	mp->mnt_stat.f_namemax = MAXNAMLEN;
159 	mp->mnt_flag |= MNT_LOCAL;
160 	mp->mnt_data = fmp;
161 	vfs_getnewfsid(mp);
162 
163 	if ((error = set_statvfs_info(path, UIO_USERSPACE, "kernfs",
164 	    UIO_SYSSPACE, mp, l)) != 0) {
165 		free(fmp, M_KERNFSMNT);
166 		return error;
167 	}
168 
169 	kernfs_get_rrootdev();
170 	return 0;
171 }
172 
173 int
174 kernfs_start(mp, flags, l)
175 	struct mount *mp;
176 	int flags;
177 	struct lwp *l;
178 {
179 
180 	return (0);
181 }
182 
183 int
184 kernfs_unmount(mp, mntflags, l)
185 	struct mount *mp;
186 	int mntflags;
187 	struct lwp *l;
188 {
189 	int error;
190 	int flags = 0;
191 
192 	if (mntflags & MNT_FORCE)
193 		flags |= FORCECLOSE;
194 
195 	if ((error = vflush(mp, 0, flags)) != 0)
196 		return (error);
197 
198 	/*
199 	 * Finally, throw away the kernfs_mount structure
200 	 */
201 	free(mp->mnt_data, M_KERNFSMNT);
202 	mp->mnt_data = NULL;
203 	return (0);
204 }
205 
206 int
207 kernfs_root(mp, vpp)
208 	struct mount *mp;
209 	struct vnode **vpp;
210 {
211 
212 	/* setup "." */
213 	return (kernfs_allocvp(mp, vpp, KFSkern, &kern_targets[0], 0));
214 }
215 
216 int
217 kernfs_quotactl(mp, cmd, uid, arg, l)
218 	struct mount *mp;
219 	int cmd;
220 	uid_t uid;
221 	void *arg;
222 	struct lwp *l;
223 {
224 
225 	return (EOPNOTSUPP);
226 }
227 
228 int
229 kernfs_statvfs(mp, sbp, l)
230 	struct mount *mp;
231 	struct statvfs *sbp;
232 	struct lwp *l;
233 {
234 
235 	sbp->f_bsize = DEV_BSIZE;
236 	sbp->f_frsize = DEV_BSIZE;
237 	sbp->f_iosize = DEV_BSIZE;
238 	sbp->f_blocks = 2;		/* 1K to keep df happy */
239 	sbp->f_bfree = 0;
240 	sbp->f_bavail = 0;
241 	sbp->f_bresvd = 0;
242 	sbp->f_files = 1024;	/* XXX lie */
243 	sbp->f_ffree = 128;	/* XXX lie */
244 	sbp->f_favail = 128;	/* XXX lie */
245 	sbp->f_fresvd = 0;
246 	copy_statvfs_info(sbp, mp);
247 	return (0);
248 }
249 
250 /*ARGSUSED*/
251 int
252 kernfs_sync(mp, waitfor, uc, l)
253 	struct mount *mp;
254 	int waitfor;
255 	kauth_cred_t uc;
256 	struct lwp *l;
257 {
258 
259 	return (0);
260 }
261 
262 /*
263  * Kernfs flat namespace lookup.
264  * Currently unsupported.
265  */
266 int
267 kernfs_vget(mp, ino, vpp)
268 	struct mount *mp;
269 	ino_t ino;
270 	struct vnode **vpp;
271 {
272 
273 	return (EOPNOTSUPP);
274 }
275 
276 SYSCTL_SETUP(sysctl_vfs_kernfs_setup, "sysctl vfs.kern subtree setup")
277 {
278 
279 	sysctl_createv(clog, 0, NULL, NULL,
280 		       CTLFLAG_PERMANENT,
281 		       CTLTYPE_NODE, "vfs", NULL,
282 		       NULL, 0, NULL, 0,
283 		       CTL_VFS, CTL_EOL);
284 	sysctl_createv(clog, 0, NULL, NULL,
285 		       CTLFLAG_PERMANENT,
286 		       CTLTYPE_NODE, "kernfs",
287 		       SYSCTL_DESCR("/kern file system"),
288 		       NULL, 0, NULL, 0,
289 		       CTL_VFS, 11, CTL_EOL);
290 	/*
291 	 * XXX the "11" above could be dynamic, thereby eliminating one
292 	 * more instance of the "number to vfs" mapping problem, but
293 	 * "11" is the order as taken from sys/mount.h
294 	 */
295 }
296 
297 extern const struct vnodeopv_desc kernfs_vnodeop_opv_desc;
298 
299 const struct vnodeopv_desc * const kernfs_vnodeopv_descs[] = {
300 	&kernfs_vnodeop_opv_desc,
301 	NULL,
302 };
303 
304 struct vfsops kernfs_vfsops = {
305 	MOUNT_KERNFS,
306 	kernfs_mount,
307 	kernfs_start,
308 	kernfs_unmount,
309 	kernfs_root,
310 	kernfs_quotactl,
311 	kernfs_statvfs,
312 	kernfs_sync,
313 	kernfs_vget,
314 	NULL,				/* vfs_fhtovp */
315 	NULL,				/* vfs_vptofh */
316 	kernfs_init,
317 	kernfs_reinit,
318 	kernfs_done,
319 	NULL,				/* vfs_mountroot */
320 	(int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
321 	vfs_stdextattrctl,
322 	kernfs_vnodeopv_descs,
323 };
324 VFS_ATTACH(kernfs_vfsops);
325