kernfs_vfsops.c revision 1.39 1 /* $NetBSD: kernfs_vfsops.c,v 1.39 2001/02/04 10:20:00 mrg 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_done __P((void));
66 void kernfs_get_rrootdev __P((void));
67 int kernfs_mount __P((struct mount *, const char *, void *,
68 struct nameidata *, struct proc *));
69 int kernfs_start __P((struct mount *, int, struct proc *));
70 int kernfs_unmount __P((struct mount *, int, struct proc *));
71 int kernfs_root __P((struct mount *, struct vnode **));
72 int kernfs_statfs __P((struct mount *, struct statfs *, struct proc *));
73 int kernfs_quotactl __P((struct mount *, int, uid_t, caddr_t,
74 struct proc *));
75 int kernfs_sync __P((struct mount *, int, struct ucred *, struct proc *));
76 int kernfs_vget __P((struct mount *, ino_t, struct vnode **));
77 int kernfs_fhtovp __P((struct mount *, struct fid *, struct vnode **));
78 int kernfs_checkexp __P((struct mount *, struct mbuf *, int *,
79 struct ucred **));
80 int kernfs_vptofh __P((struct vnode *, struct fid *));
81 int kernfs_sysctl __P((int *, u_int, void *, size_t *, void *, size_t,
82 struct proc *));
83
84 void
85 kernfs_init()
86 {
87 }
88
89 void
90 kernfs_done()
91 {
92 }
93
94 void
95 kernfs_get_rrootdev()
96 {
97 static int tried = 0;
98 int cmaj;
99
100 if (tried) {
101 /* Already did it once. */
102 return;
103 }
104 tried = 1;
105
106 if (rootdev == NODEV)
107 return;
108 for (cmaj = 0; cmaj < nchrdev; cmaj++) {
109 rrootdev = makedev(cmaj, minor(rootdev));
110 if (chrtoblk(rrootdev) == rootdev) {
111 #ifdef KERNFS_DIAGNOSTIC
112 printf("kernfs_mount: rootdev = %u.%u; rrootdev = %u.%u\n",
113 major(rootdev), minor(rootdev), major(rrootdev), minor(rrootdev));
114 #endif
115 return;
116 }
117 }
118 rrootdev = NODEV;
119 printf("kernfs_get_rrootdev: no raw root device\n");
120 }
121
122 /*
123 * Mount the Kernel params filesystem
124 */
125 int
126 kernfs_mount(mp, path, data, ndp, p)
127 struct mount *mp;
128 const char *path;
129 void *data;
130 struct nameidata *ndp;
131 struct proc *p;
132 {
133 int error = 0;
134 size_t size;
135 struct kernfs_mount *fmp;
136 struct vnode *rvp;
137
138 #ifdef KERNFS_DIAGNOSTIC
139 printf("kernfs_mount(mp = %p)\n", mp);
140 #endif
141
142 /*
143 * Update is a no-op
144 */
145 if (mp->mnt_flag & MNT_UPDATE)
146 return (EOPNOTSUPP);
147
148 error = getnewvnode(VT_KERNFS, mp, kernfs_vnodeop_p, &rvp);
149 if (error)
150 return (error);
151
152 MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
153 M_MISCFSMNT, M_WAITOK);
154 rvp->v_type = VDIR;
155 rvp->v_flag |= VROOT;
156 #ifdef KERNFS_DIAGNOSTIC
157 printf("kernfs_mount: root vp = %p\n", rvp);
158 #endif
159 fmp->kf_root = rvp;
160 mp->mnt_flag |= MNT_LOCAL;
161 mp->mnt_data = (qaddr_t)fmp;
162 vfs_getnewfsid(mp);
163
164 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
165 memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size);
166 memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN);
167 memcpy(mp->mnt_stat.f_mntfromname, "kernfs", sizeof("kernfs"));
168 #ifdef KERNFS_DIAGNOSTIC
169 printf("kernfs_mount: at %s\n", mp->mnt_stat.f_mntonname);
170 #endif
171
172 kernfs_get_rrootdev();
173 return (0);
174 }
175
176 int
177 kernfs_start(mp, flags, p)
178 struct mount *mp;
179 int flags;
180 struct proc *p;
181 {
182
183 return (0);
184 }
185
186 int
187 kernfs_unmount(mp, mntflags, p)
188 struct mount *mp;
189 int mntflags;
190 struct proc *p;
191 {
192 int error;
193 int flags = 0;
194 struct vnode *rootvp = VFSTOKERNFS(mp)->kf_root;
195
196 #ifdef KERNFS_DIAGNOSTIC
197 printf("kernfs_unmount(mp = %p)\n", mp);
198 #endif
199
200 if (mntflags & MNT_FORCE)
201 flags |= FORCECLOSE;
202
203 /*
204 * Clear out buffer cache. I don't think we
205 * ever get anything cached at this level at the
206 * moment, but who knows...
207 */
208 if (rootvp->v_usecount > 1)
209 return (EBUSY);
210 #ifdef KERNFS_DIAGNOSTIC
211 printf("kernfs_unmount: calling vflush\n");
212 #endif
213 if ((error = vflush(mp, rootvp, flags)) != 0)
214 return (error);
215
216 #ifdef KERNFS_DIAGNOSTIC
217 vprint("kernfs root", rootvp);
218 #endif
219 /*
220 * Clean out the old root vnode for reuse.
221 */
222 vrele(rootvp);
223 vgone(rootvp);
224 /*
225 * Finally, throw away the kernfs_mount structure
226 */
227 free(mp->mnt_data, M_MISCFSMNT);
228 mp->mnt_data = 0;
229 return (0);
230 }
231
232 int
233 kernfs_root(mp, vpp)
234 struct mount *mp;
235 struct vnode **vpp;
236 {
237 struct vnode *vp;
238
239 #ifdef KERNFS_DIAGNOSTIC
240 printf("kernfs_root(mp = %p)\n", mp);
241 #endif
242
243 /*
244 * Return locked reference to root.
245 */
246 vp = VFSTOKERNFS(mp)->kf_root;
247 VREF(vp);
248 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
249 *vpp = vp;
250 return (0);
251 }
252
253 int
254 kernfs_quotactl(mp, cmd, uid, arg, p)
255 struct mount *mp;
256 int cmd;
257 uid_t uid;
258 caddr_t arg;
259 struct proc *p;
260 {
261
262 return (EOPNOTSUPP);
263 }
264
265 int
266 kernfs_statfs(mp, sbp, p)
267 struct mount *mp;
268 struct statfs *sbp;
269 struct proc *p;
270 {
271
272 #ifdef KERNFS_DIAGNOSTIC
273 printf("kernfs_statfs(mp = %p)\n", mp);
274 #endif
275
276 sbp->f_bsize = DEV_BSIZE;
277 sbp->f_iosize = DEV_BSIZE;
278 sbp->f_blocks = 2; /* 1K to keep df happy */
279 sbp->f_bfree = 0;
280 sbp->f_bavail = 0;
281 sbp->f_files = 0;
282 sbp->f_ffree = 0;
283 #ifdef COMPAT_09
284 sbp->f_type = 7;
285 #else
286 sbp->f_type = 0;
287 #endif
288 if (sbp != &mp->mnt_stat) {
289 memcpy(&sbp->f_fsid, &mp->mnt_stat.f_fsid, sizeof(sbp->f_fsid));
290 memcpy(sbp->f_mntonname, mp->mnt_stat.f_mntonname, MNAMELEN);
291 memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname, MNAMELEN);
292 }
293 strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN);
294 return (0);
295 }
296
297 /*ARGSUSED*/
298 int
299 kernfs_sync(mp, waitfor, uc, p)
300 struct mount *mp;
301 int waitfor;
302 struct ucred *uc;
303 struct proc *p;
304 {
305
306 return (0);
307 }
308
309 /*
310 * Kernfs flat namespace lookup.
311 * Currently unsupported.
312 */
313 int
314 kernfs_vget(mp, ino, vpp)
315 struct mount *mp;
316 ino_t ino;
317 struct vnode **vpp;
318 {
319
320 return (EOPNOTSUPP);
321 }
322
323 /*ARGSUSED*/
324 int
325 kernfs_fhtovp(mp, fhp, vpp)
326 struct mount *mp;
327 struct fid *fhp;
328 struct vnode **vpp;
329 {
330
331 return (EOPNOTSUPP);
332 }
333
334 /*ARGSUSED*/
335 int
336 kernfs_checkexp(mp, mb, what, anon)
337 struct mount *mp;
338 struct mbuf *mb;
339 int *what;
340 struct ucred **anon;
341 {
342
343 return (EOPNOTSUPP);
344 }
345
346 /*ARGSUSED*/
347 int
348 kernfs_vptofh(vp, fhp)
349 struct vnode *vp;
350 struct fid *fhp;
351 {
352
353 return (EOPNOTSUPP);
354 }
355
356 int
357 kernfs_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
358 int *name;
359 u_int namelen;
360 void *oldp;
361 size_t *oldlenp;
362 void *newp;
363 size_t newlen;
364 struct proc *p;
365 {
366 return (EOPNOTSUPP);
367 }
368
369 extern const struct vnodeopv_desc kernfs_vnodeop_opv_desc;
370
371 const struct vnodeopv_desc * const kernfs_vnodeopv_descs[] = {
372 &kernfs_vnodeop_opv_desc,
373 NULL,
374 };
375
376 struct vfsops kernfs_vfsops = {
377 MOUNT_KERNFS,
378 kernfs_mount,
379 kernfs_start,
380 kernfs_unmount,
381 kernfs_root,
382 kernfs_quotactl,
383 kernfs_statfs,
384 kernfs_sync,
385 kernfs_vget,
386 kernfs_fhtovp,
387 kernfs_vptofh,
388 kernfs_init,
389 kernfs_done,
390 kernfs_sysctl,
391 NULL, /* vfs_mountroot */
392 kernfs_checkexp,
393 kernfs_vnodeopv_descs,
394 };
395