fdesc_vfsops.c revision 1.39 1 /* $NetBSD: fdesc_vfsops.c,v 1.39 2003/04/16 21:44:22 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. 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 * @(#)fdesc_vfsops.c 8.10 (Berkeley) 5/14/95
39 *
40 * #Id: fdesc_vfsops.c,v 1.9 1993/04/06 15:28:33 jsp Exp #
41 */
42
43 /*
44 * /dev/fd Filesystem
45 */
46
47 #include <sys/cdefs.h>
48 __KERNEL_RCSID(0, "$NetBSD: fdesc_vfsops.c,v 1.39 2003/04/16 21:44:22 christos Exp $");
49
50 #if defined(_KERNEL_OPT)
51 #include "opt_compat_netbsd.h"
52 #endif
53
54 #include <sys/param.h>
55 #include <sys/systm.h>
56 #include <sys/time.h>
57 #include <sys/proc.h>
58 #include <sys/resourcevar.h>
59 #include <sys/filedesc.h>
60 #include <sys/vnode.h>
61 #include <sys/mount.h>
62 #include <sys/namei.h>
63 #include <sys/malloc.h>
64 #include <miscfs/fdesc/fdesc.h>
65
66 int fdesc_mount __P((struct mount *, const char *, void *,
67 struct nameidata *, struct proc *));
68 int fdesc_start __P((struct mount *, int, struct proc *));
69 int fdesc_unmount __P((struct mount *, int, struct proc *));
70 int fdesc_quotactl __P((struct mount *, int, uid_t, caddr_t,
71 struct proc *));
72 int fdesc_statfs __P((struct mount *, struct statfs *, struct proc *));
73 int fdesc_sync __P((struct mount *, int, struct ucred *, struct proc *));
74 int fdesc_vget __P((struct mount *, ino_t, struct vnode **));
75 int fdesc_fhtovp __P((struct mount *, struct fid *, struct vnode **));
76 int fdesc_checkexp __P((struct mount *, struct mbuf *, int *,
77 struct ucred **));
78 int fdesc_vptofh __P((struct vnode *, struct fid *));
79 int fdesc_sysctl __P((int *, u_int, void *, size_t *, void *, size_t,
80 struct proc *));
81
82 /*
83 * Mount the per-process file descriptors (/dev/fd)
84 */
85 int
86 fdesc_mount(mp, path, data, ndp, p)
87 struct mount *mp;
88 const char *path;
89 void *data;
90 struct nameidata *ndp;
91 struct proc *p;
92 {
93 int error = 0;
94 struct fdescmount *fmp;
95 struct vnode *rvp;
96
97 if (mp->mnt_flag & MNT_GETARGS)
98 return 0;
99 /*
100 * Update is a no-op
101 */
102 if (mp->mnt_flag & MNT_UPDATE)
103 return (EOPNOTSUPP);
104
105 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp);
106 if (error)
107 return (error);
108
109 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
110 M_UFSMNT, M_WAITOK); /* XXX */
111 rvp->v_type = VDIR;
112 rvp->v_flag |= VROOT;
113 fmp->f_root = rvp;
114 mp->mnt_flag |= MNT_LOCAL;
115 mp->mnt_data = fmp;
116 vfs_getnewfsid(mp);
117
118 error = set_statfs_info(path, UIO_USERSPACE, "fdesc", UIO_SYSSPACE,
119 mp, p);
120 VOP_UNLOCK(rvp, 0);
121 return error;
122 }
123
124 int
125 fdesc_start(mp, flags, p)
126 struct mount *mp;
127 int flags;
128 struct proc *p;
129 {
130 return (0);
131 }
132
133 int
134 fdesc_unmount(mp, mntflags, p)
135 struct mount *mp;
136 int mntflags;
137 struct proc *p;
138 {
139 int error;
140 int flags = 0;
141 struct vnode *rootvp = VFSTOFDESC(mp)->f_root;
142
143 if (mntflags & MNT_FORCE)
144 flags |= FORCECLOSE;
145
146 /*
147 * Clear out buffer cache. I don't think we
148 * ever get anything cached at this level at the
149 * moment, but who knows...
150 */
151 if (rootvp->v_usecount > 1)
152 return (EBUSY);
153 if ((error = vflush(mp, rootvp, flags)) != 0)
154 return (error);
155
156 /*
157 * Release reference on underlying root vnode
158 */
159 vrele(rootvp);
160 /*
161 * And blow it away for future re-use
162 */
163 vgone(rootvp);
164 /*
165 * Finally, throw away the fdescmount structure
166 */
167 free(mp->mnt_data, M_UFSMNT); /* XXX */
168 mp->mnt_data = 0;
169
170 return (0);
171 }
172
173 int
174 fdesc_root(mp, vpp)
175 struct mount *mp;
176 struct vnode **vpp;
177 {
178 struct vnode *vp;
179
180 /*
181 * Return locked reference to root.
182 */
183 vp = VFSTOFDESC(mp)->f_root;
184 VREF(vp);
185 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
186 *vpp = vp;
187 return (0);
188 }
189
190 int
191 fdesc_quotactl(mp, cmd, uid, arg, p)
192 struct mount *mp;
193 int cmd;
194 uid_t uid;
195 caddr_t arg;
196 struct proc *p;
197 {
198
199 return (EOPNOTSUPP);
200 }
201
202 int
203 fdesc_statfs(mp, sbp, p)
204 struct mount *mp;
205 struct statfs *sbp;
206 struct proc *p;
207 {
208 struct filedesc *fdp;
209 int lim;
210 int i;
211 int last;
212 int freefd;
213
214 /*
215 * Compute number of free file descriptors.
216 * [ Strange results will ensue if the open file
217 * limit is ever reduced below the current number
218 * of open files... ]
219 */
220 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur;
221 fdp = p->p_fd;
222 last = min(fdp->fd_nfiles, lim);
223 freefd = 0;
224 for (i = fdp->fd_freefile; i < last; i++)
225 if (fdp->fd_ofiles[i] == NULL)
226 freefd++;
227
228 /*
229 * Adjust for the fact that the fdesc array may not
230 * have been fully allocated yet.
231 */
232 if (fdp->fd_nfiles < lim)
233 freefd += (lim - fdp->fd_nfiles);
234
235 sbp->f_bsize = DEV_BSIZE;
236 sbp->f_iosize = DEV_BSIZE;
237 sbp->f_blocks = 2; /* 1K to keep df happy */
238 sbp->f_bfree = 0;
239 sbp->f_bavail = 0;
240 sbp->f_files = lim + 1; /* Allow for "." */
241 sbp->f_ffree = freefd; /* See comments above */
242 #ifdef COMPAT_09
243 sbp->f_type = 6;
244 #else
245 sbp->f_type = 0;
246 #endif
247 copy_statfs_info(sbp, mp);
248 return (0);
249 }
250
251 /*ARGSUSED*/
252 int
253 fdesc_sync(mp, waitfor, uc, p)
254 struct mount *mp;
255 int waitfor;
256 struct ucred *uc;
257 struct proc *p;
258 {
259
260 return (0);
261 }
262
263 /*
264 * Fdesc flat namespace lookup.
265 * Currently unsupported.
266 */
267 int
268 fdesc_vget(mp, ino, vpp)
269 struct mount *mp;
270 ino_t ino;
271 struct vnode **vpp;
272 {
273
274 return (EOPNOTSUPP);
275 }
276
277
278 /*ARGSUSED*/
279 int
280 fdesc_fhtovp(mp, fhp, vpp)
281 struct mount *mp;
282 struct fid *fhp;
283 struct vnode **vpp;
284 {
285
286 return (EOPNOTSUPP);
287 }
288
289 /*ARGSUSED*/
290 int
291 fdesc_checkexp(mp, nam, exflagsp, credanonp)
292 struct mount *mp;
293 struct mbuf *nam;
294 int *exflagsp;
295 struct ucred **credanonp;
296 {
297
298 return (EOPNOTSUPP);
299 }
300
301 /*ARGSUSED*/
302 int
303 fdesc_vptofh(vp, fhp)
304 struct vnode *vp;
305 struct fid *fhp;
306 {
307 return (EOPNOTSUPP);
308 }
309
310 int
311 fdesc_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
312 int *name;
313 u_int namelen;
314 void *oldp;
315 size_t *oldlenp;
316 void *newp;
317 size_t newlen;
318 struct proc *p;
319 {
320 return (EOPNOTSUPP);
321 }
322
323 extern const struct vnodeopv_desc fdesc_vnodeop_opv_desc;
324
325 const struct vnodeopv_desc * const fdesc_vnodeopv_descs[] = {
326 &fdesc_vnodeop_opv_desc,
327 NULL,
328 };
329
330 struct vfsops fdesc_vfsops = {
331 MOUNT_FDESC,
332 fdesc_mount,
333 fdesc_start,
334 fdesc_unmount,
335 fdesc_root,
336 fdesc_quotactl,
337 fdesc_statfs,
338 fdesc_sync,
339 fdesc_vget,
340 fdesc_fhtovp,
341 fdesc_vptofh,
342 fdesc_init,
343 NULL,
344 fdesc_done,
345 fdesc_sysctl,
346 NULL, /* vfs_mountroot */
347 fdesc_checkexp,
348 fdesc_vnodeopv_descs,
349 };
350