kernfs_vfsops.c revision 1.31 1 /* $NetBSD: kernfs_vfsops.c,v 1.31 1998/02/18 07:05:48 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993
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 8.5 (Berkeley) 6/15/94
39 */
40
41 /*
42 * Kernel params Filesystem
43 */
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/conf.h>
48 #include <sys/types.h>
49 #include <sys/proc.h>
50 #include <sys/vnode.h>
51 #include <sys/mount.h>
52 #include <sys/namei.h>
53 #include <sys/malloc.h>
54
55 #include <miscfs/specfs/specdev.h>
56 #include <miscfs/kernfs/kernfs.h>
57
58 dev_t rrootdev = NODEV;
59
60 void kernfs_init __P((void));
61 void kernfs_get_rrootdev __P((void));
62 int kernfs_mount __P((struct mount *, const char *, void *,
63 struct nameidata *, struct proc *));
64 int kernfs_start __P((struct mount *, int, struct proc *));
65 int kernfs_unmount __P((struct mount *, int, struct proc *));
66 int kernfs_root __P((struct mount *, struct vnode **));
67 int kernfs_statfs __P((struct mount *, struct statfs *, struct proc *));
68 int kernfs_quotactl __P((struct mount *, int, uid_t, caddr_t,
69 struct proc *));
70 int kernfs_sync __P((struct mount *, int, struct ucred *, struct proc *));
71 int kernfs_vget __P((struct mount *, ino_t, struct vnode **));
72 int kernfs_fhtovp __P((struct mount *, struct fid *, struct mbuf *,
73 struct vnode **, int *, struct ucred **));
74 int kernfs_vptofh __P((struct vnode *, struct fid *));
75
76 /*ARGSUSED*/
77 void
78 kernfs_init()
79 {
80 }
81
82 void
83 kernfs_get_rrootdev()
84 {
85 static int tried = 0;
86 int cmaj;
87
88 if (tried) {
89 /* Already did it once. */
90 return;
91 }
92 tried = 1;
93
94 if (rootdev == NODEV)
95 return;
96 for (cmaj = 0; cmaj < nchrdev; cmaj++) {
97 rrootdev = makedev(cmaj, minor(rootdev));
98 if (chrtoblk(rrootdev) == rootdev)
99 return;
100 }
101 rrootdev = NODEV;
102 printf("kernfs_get_rrootdev: no raw root device\n");
103 }
104
105 /*
106 * Mount the Kernel params filesystem
107 */
108 int
109 kernfs_mount(mp, path, data, ndp, p)
110 struct mount *mp;
111 const char *path;
112 void *data;
113 struct nameidata *ndp;
114 struct proc *p;
115 {
116 int error = 0;
117 size_t size;
118 struct kernfs_mount *fmp;
119 struct vnode *rvp;
120
121 #ifdef KERNFS_DIAGNOSTIC
122 printf("kernfs_mount(mp = %p)\n", mp);
123 #endif
124
125 /*
126 * Update is a no-op
127 */
128 if (mp->mnt_flag & MNT_UPDATE)
129 return (EOPNOTSUPP);
130
131 error = getnewvnode(VT_KERNFS, mp, kernfs_vnodeop_p, &rvp);
132 if (error)
133 return (error);
134
135 MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
136 M_MISCFSMNT, M_WAITOK);
137 rvp->v_type = VDIR;
138 rvp->v_flag |= VROOT;
139 #ifdef KERNFS_DIAGNOSTIC
140 printf("kernfs_mount: root vp = %p\n", rvp);
141 #endif
142 fmp->kf_root = rvp;
143 mp->mnt_flag |= MNT_LOCAL;
144 mp->mnt_data = (qaddr_t)fmp;
145 getnewfsid(mp, makefstype(MOUNT_KERNFS));
146
147 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
148 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
149 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
150 bcopy("kernfs", mp->mnt_stat.f_mntfromname, sizeof("kernfs"));
151 #ifdef KERNFS_DIAGNOSTIC
152 printf("kernfs_mount: at %s\n", mp->mnt_stat.f_mntonname);
153 #endif
154
155 kernfs_get_rrootdev();
156 return (0);
157 }
158
159 int
160 kernfs_start(mp, flags, p)
161 struct mount *mp;
162 int flags;
163 struct proc *p;
164 {
165
166 return (0);
167 }
168
169 int
170 kernfs_unmount(mp, mntflags, p)
171 struct mount *mp;
172 int mntflags;
173 struct proc *p;
174 {
175 int error;
176 int flags = 0;
177 extern int doforce;
178 struct vnode *rootvp = VFSTOKERNFS(mp)->kf_root;
179
180 #ifdef KERNFS_DIAGNOSTIC
181 printf("kernfs_unmount(mp = %p)\n", mp);
182 #endif
183
184 if (mntflags & MNT_FORCE) {
185 /* kernfs can never be rootfs so don't check for it */
186 if (!doforce)
187 return (EINVAL);
188 flags |= FORCECLOSE;
189 }
190
191 /*
192 * Clear out buffer cache. I don't think we
193 * ever get anything cached at this level at the
194 * moment, but who knows...
195 */
196 if (rootvp->v_usecount > 1)
197 return (EBUSY);
198 #ifdef KERNFS_DIAGNOSTIC
199 printf("kernfs_unmount: calling vflush\n");
200 #endif
201 if ((error = vflush(mp, rootvp, flags)) != 0)
202 return (error);
203
204 #ifdef KERNFS_DIAGNOSTIC
205 vprint("kernfs root", rootvp);
206 #endif
207 /*
208 * Clean out the old root vnode for reuse.
209 */
210 vrele(rootvp);
211 vgone(rootvp);
212 /*
213 * Finally, throw away the kernfs_mount structure
214 */
215 free(mp->mnt_data, M_MISCFSMNT);
216 mp->mnt_data = 0;
217 return (0);
218 }
219
220 int
221 kernfs_root(mp, vpp)
222 struct mount *mp;
223 struct vnode **vpp;
224 {
225 struct vnode *vp;
226
227 #ifdef KERNFS_DIAGNOSTIC
228 printf("kernfs_root(mp = %p)\n", mp);
229 #endif
230
231 /*
232 * Return locked reference to root.
233 */
234 vp = VFSTOKERNFS(mp)->kf_root;
235 VREF(vp);
236 VOP_LOCK(vp);
237 *vpp = vp;
238 return (0);
239 }
240
241 int
242 kernfs_quotactl(mp, cmd, uid, arg, p)
243 struct mount *mp;
244 int cmd;
245 uid_t uid;
246 caddr_t arg;
247 struct proc *p;
248 {
249
250 return (EOPNOTSUPP);
251 }
252
253 int
254 kernfs_statfs(mp, sbp, p)
255 struct mount *mp;
256 struct statfs *sbp;
257 struct proc *p;
258 {
259
260 #ifdef KERNFS_DIAGNOSTIC
261 printf("kernfs_statfs(mp = %p)\n", mp);
262 #endif
263
264 #ifdef COMPAT_09
265 sbp->f_type = 7;
266 #else
267 sbp->f_type = 0;
268 #endif
269 sbp->f_bsize = DEV_BSIZE;
270 sbp->f_iosize = DEV_BSIZE;
271 sbp->f_blocks = 2; /* 1K to keep df happy */
272 sbp->f_bfree = 0;
273 sbp->f_bavail = 0;
274 sbp->f_files = 0;
275 sbp->f_ffree = 0;
276 if (sbp != &mp->mnt_stat) {
277 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
278 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
279 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
280 }
281 strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN);
282 return (0);
283 }
284
285 /*ARGSUSED*/
286 int
287 kernfs_sync(mp, waitfor, uc, p)
288 struct mount *mp;
289 int waitfor;
290 struct ucred *uc;
291 struct proc *p;
292 {
293
294 return (0);
295 }
296
297 /*
298 * Kernfs flat namespace lookup.
299 * Currently unsupported.
300 */
301 int
302 kernfs_vget(mp, ino, vpp)
303 struct mount *mp;
304 ino_t ino;
305 struct vnode **vpp;
306 {
307
308 return (EOPNOTSUPP);
309 }
310
311 /*ARGSUSED*/
312 int
313 kernfs_fhtovp(mp, fhp, mb, vpp, what, anon)
314 struct mount *mp;
315 struct fid *fhp;
316 struct mbuf *mb;
317 struct vnode **vpp;
318 int *what;
319 struct ucred **anon;
320 {
321
322 return (EOPNOTSUPP);
323 }
324
325 /*ARGSUSED*/
326 int
327 kernfs_vptofh(vp, fhp)
328 struct vnode *vp;
329 struct fid *fhp;
330 {
331
332 return (EOPNOTSUPP);
333 }
334
335 extern struct vnodeopv_desc kernfs_vnodeop_opv_desc;
336
337 struct vnodeopv_desc *kernfs_vnodeopv_descs[] = {
338 &kernfs_vnodeop_opv_desc,
339 NULL,
340 };
341
342 struct vfsops kernfs_vfsops = {
343 MOUNT_KERNFS,
344 kernfs_mount,
345 kernfs_start,
346 kernfs_unmount,
347 kernfs_root,
348 kernfs_quotactl,
349 kernfs_statfs,
350 kernfs_sync,
351 kernfs_vget,
352 kernfs_fhtovp,
353 kernfs_vptofh,
354 kernfs_init,
355 NULL, /* vfs_mountroot */
356 kernfs_vnodeopv_descs,
357 };
358