xref: /netbsd-src/sys/miscfs/kernfs/kernfs_vfsops.c (revision e4d7c2e329d54c97e0c0bd3016bbe74f550c3d5e)
1 /*	$NetBSD: kernfs_vfsops.c,v 1.35 1999/02/26 23:44:45 wrstuden 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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)kernfs_vfsops.c	8.10 (Berkeley) 5/14/95
39  */
40 
41 /*
42  * Kernel params Filesystem
43  */
44 
45 #if defined(_KERNEL) && !defined(_LKM)
46 #include "opt_compat_netbsd.h"
47 #endif
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/conf.h>
52 #include <sys/types.h>
53 #include <sys/proc.h>
54 #include <sys/vnode.h>
55 #include <sys/mount.h>
56 #include <sys/namei.h>
57 #include <sys/malloc.h>
58 
59 #include <miscfs/specfs/specdev.h>
60 #include <miscfs/kernfs/kernfs.h>
61 
62 dev_t rrootdev = NODEV;
63 
64 void	kernfs_init __P((void));
65 void	kernfs_get_rrootdev __P((void));
66 int	kernfs_mount __P((struct mount *, const char *, void *,
67 	    struct nameidata *, struct proc *));
68 int	kernfs_start __P((struct mount *, int, struct proc *));
69 int	kernfs_unmount __P((struct mount *, int, struct proc *));
70 int	kernfs_root __P((struct mount *, struct vnode **));
71 int	kernfs_statfs __P((struct mount *, struct statfs *, struct proc *));
72 int	kernfs_quotactl __P((struct mount *, int, uid_t, caddr_t,
73 			     struct proc *));
74 int	kernfs_sync __P((struct mount *, int, struct ucred *, struct proc *));
75 int	kernfs_vget __P((struct mount *, ino_t, struct vnode **));
76 int	kernfs_fhtovp __P((struct mount *, struct fid *, struct vnode **));
77 int	kernfs_checkexp __P((struct mount *, struct mbuf *, int *,
78 			   struct ucred **));
79 int	kernfs_vptofh __P((struct vnode *, struct fid *));
80 int	kernfs_sysctl __P((int *, u_int, void *, size_t *, void *, size_t,
81 			   struct proc *));
82 
83 void
84 kernfs_init()
85 {
86 }
87 
88 void
89 kernfs_get_rrootdev()
90 {
91 	static int tried = 0;
92 	int cmaj;
93 
94 	if (tried) {
95 		/* Already did it once. */
96 		return;
97 	}
98 	tried = 1;
99 
100 	if (rootdev == NODEV)
101 		return;
102 	for (cmaj = 0; cmaj < nchrdev; cmaj++) {
103 		rrootdev = makedev(cmaj, minor(rootdev));
104 		if (chrtoblk(rrootdev) == rootdev)
105 			return;
106 	}
107 	rrootdev = NODEV;
108 	printf("kernfs_get_rrootdev: no raw root device\n");
109 }
110 
111 /*
112  * Mount the Kernel params filesystem
113  */
114 int
115 kernfs_mount(mp, path, data, ndp, p)
116 	struct mount *mp;
117 	const char *path;
118 	void *data;
119 	struct nameidata *ndp;
120 	struct proc *p;
121 {
122 	int error = 0;
123 	size_t size;
124 	struct kernfs_mount *fmp;
125 	struct vnode *rvp;
126 
127 #ifdef KERNFS_DIAGNOSTIC
128 	printf("kernfs_mount(mp = %p)\n", mp);
129 #endif
130 
131 	/*
132 	 * Update is a no-op
133 	 */
134 	if (mp->mnt_flag & MNT_UPDATE)
135 		return (EOPNOTSUPP);
136 
137 	error = getnewvnode(VT_KERNFS, mp, kernfs_vnodeop_p, &rvp);
138 	if (error)
139 		return (error);
140 
141 	MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
142 	    M_MISCFSMNT, M_WAITOK);
143 	rvp->v_type = VDIR;
144 	rvp->v_flag |= VROOT;
145 #ifdef KERNFS_DIAGNOSTIC
146 	printf("kernfs_mount: root vp = %p\n", rvp);
147 #endif
148 	fmp->kf_root = rvp;
149 	mp->mnt_flag |= MNT_LOCAL;
150 	mp->mnt_data = (qaddr_t)fmp;
151 	vfs_getnewfsid(mp, MOUNT_KERNFS);
152 
153 	(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
154 	memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size);
155 	memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN);
156 	memcpy(mp->mnt_stat.f_mntfromname, "kernfs", sizeof("kernfs"));
157 #ifdef KERNFS_DIAGNOSTIC
158 	printf("kernfs_mount: at %s\n", mp->mnt_stat.f_mntonname);
159 #endif
160 
161 	kernfs_get_rrootdev();
162 	return (0);
163 }
164 
165 int
166 kernfs_start(mp, flags, p)
167 	struct mount *mp;
168 	int flags;
169 	struct proc *p;
170 {
171 
172 	return (0);
173 }
174 
175 int
176 kernfs_unmount(mp, mntflags, p)
177 	struct mount *mp;
178 	int mntflags;
179 	struct proc *p;
180 {
181 	int error;
182 	int flags = 0;
183 	struct vnode *rootvp = VFSTOKERNFS(mp)->kf_root;
184 
185 #ifdef KERNFS_DIAGNOSTIC
186 	printf("kernfs_unmount(mp = %p)\n", mp);
187 #endif
188 
189 	 if (mntflags & MNT_FORCE)
190 		flags |= FORCECLOSE;
191 
192 	/*
193 	 * Clear out buffer cache.  I don't think we
194 	 * ever get anything cached at this level at the
195 	 * moment, but who knows...
196 	 */
197 	if (rootvp->v_usecount > 1)
198 		return (EBUSY);
199 #ifdef KERNFS_DIAGNOSTIC
200 	printf("kernfs_unmount: calling vflush\n");
201 #endif
202 	if ((error = vflush(mp, rootvp, flags)) != 0)
203 		return (error);
204 
205 #ifdef KERNFS_DIAGNOSTIC
206 	vprint("kernfs root", rootvp);
207 #endif
208 	/*
209 	 * Clean out the old root vnode for reuse.
210 	 */
211 	vrele(rootvp);
212 	vgone(rootvp);
213 	/*
214 	 * Finally, throw away the kernfs_mount structure
215 	 */
216 	free(mp->mnt_data, M_MISCFSMNT);
217 	mp->mnt_data = 0;
218 	return (0);
219 }
220 
221 int
222 kernfs_root(mp, vpp)
223 	struct mount *mp;
224 	struct vnode **vpp;
225 {
226 	struct vnode *vp;
227 
228 #ifdef KERNFS_DIAGNOSTIC
229 	printf("kernfs_root(mp = %p)\n", mp);
230 #endif
231 
232 	/*
233 	 * Return locked reference to root.
234 	 */
235 	vp = VFSTOKERNFS(mp)->kf_root;
236 	VREF(vp);
237 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
238 	*vpp = vp;
239 	return (0);
240 }
241 
242 int
243 kernfs_quotactl(mp, cmd, uid, arg, p)
244 	struct mount *mp;
245 	int cmd;
246 	uid_t uid;
247 	caddr_t arg;
248 	struct proc *p;
249 {
250 
251 	return (EOPNOTSUPP);
252 }
253 
254 int
255 kernfs_statfs(mp, sbp, p)
256 	struct mount *mp;
257 	struct statfs *sbp;
258 	struct proc *p;
259 {
260 
261 #ifdef KERNFS_DIAGNOSTIC
262 	printf("kernfs_statfs(mp = %p)\n", mp);
263 #endif
264 
265 	sbp->f_bsize = DEV_BSIZE;
266 	sbp->f_iosize = DEV_BSIZE;
267 	sbp->f_blocks = 2;		/* 1K to keep df happy */
268 	sbp->f_bfree = 0;
269 	sbp->f_bavail = 0;
270 	sbp->f_files = 0;
271 	sbp->f_ffree = 0;
272 #ifdef COMPAT_09
273 	sbp->f_type = 7;
274 #else
275 	sbp->f_type = 0;
276 #endif
277 	if (sbp != &mp->mnt_stat) {
278 		memcpy(&sbp->f_fsid, &mp->mnt_stat.f_fsid, sizeof(sbp->f_fsid));
279 		memcpy(sbp->f_mntonname, mp->mnt_stat.f_mntonname, MNAMELEN);
280 		memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname, MNAMELEN);
281 	}
282 	strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN);
283 	return (0);
284 }
285 
286 /*ARGSUSED*/
287 int
288 kernfs_sync(mp, waitfor, uc, p)
289 	struct mount *mp;
290 	int waitfor;
291 	struct ucred *uc;
292 	struct proc *p;
293 {
294 
295 	return (0);
296 }
297 
298 /*
299  * Kernfs flat namespace lookup.
300  * Currently unsupported.
301  */
302 int
303 kernfs_vget(mp, ino, vpp)
304 	struct mount *mp;
305 	ino_t ino;
306 	struct vnode **vpp;
307 {
308 
309 	return (EOPNOTSUPP);
310 }
311 
312 /*ARGSUSED*/
313 int
314 kernfs_fhtovp(mp, fhp, vpp)
315 	struct mount *mp;
316 	struct fid *fhp;
317 	struct vnode **vpp;
318 {
319 
320 	return (EOPNOTSUPP);
321 }
322 
323 /*ARGSUSED*/
324 int
325 kernfs_checkexp(mp, mb, what, anon)
326 	struct mount *mp;
327 	struct mbuf *mb;
328 	int *what;
329 	struct ucred **anon;
330 {
331 
332 	return (EOPNOTSUPP);
333 }
334 
335 /*ARGSUSED*/
336 int
337 kernfs_vptofh(vp, fhp)
338 	struct vnode *vp;
339 	struct fid *fhp;
340 {
341 
342 	return (EOPNOTSUPP);
343 }
344 
345 int
346 kernfs_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
347 	int *name;
348 	u_int namelen;
349 	void *oldp;
350 	size_t *oldlenp;
351 	void *newp;
352 	size_t newlen;
353 	struct proc *p;
354 {
355 	return (EOPNOTSUPP);
356 }
357 
358 extern struct vnodeopv_desc kernfs_vnodeop_opv_desc;
359 
360 struct vnodeopv_desc *kernfs_vnodeopv_descs[] = {
361 	&kernfs_vnodeop_opv_desc,
362 	NULL,
363 };
364 
365 struct vfsops kernfs_vfsops = {
366 	MOUNT_KERNFS,
367 	kernfs_mount,
368 	kernfs_start,
369 	kernfs_unmount,
370 	kernfs_root,
371 	kernfs_quotactl,
372 	kernfs_statfs,
373 	kernfs_sync,
374 	kernfs_vget,
375 	kernfs_fhtovp,
376 	kernfs_vptofh,
377 	kernfs_init,
378 	kernfs_sysctl,
379 	NULL,				/* vfs_mountroot */
380 	kernfs_checkexp,
381 	kernfs_vnodeopv_descs,
382 };
383