xref: /netbsd-src/sys/miscfs/procfs/procfs_vfsops.c (revision fff57c5525bbe431aee7bdb3983954f0627a42cb)
1 /*	$NetBSD: procfs_vfsops.c,v 1.80 2008/05/13 08:31:13 simonb Exp $	*/
2 
3 /*
4  * Copyright (c) 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed 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  *	@(#)procfs_vfsops.c	8.7 (Berkeley) 5/10/95
35  */
36 
37 /*
38  * Copyright (c) 1993 Jan-Simon Pendry
39  *
40  * This code is derived from software contributed to Berkeley by
41  * Jan-Simon Pendry.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)procfs_vfsops.c	8.7 (Berkeley) 5/10/95
72  */
73 
74 /*
75  * procfs VFS interface
76  */
77 
78 #include <sys/cdefs.h>
79 __KERNEL_RCSID(0, "$NetBSD: procfs_vfsops.c,v 1.80 2008/05/13 08:31:13 simonb Exp $");
80 
81 #if defined(_KERNEL_OPT)
82 #include "opt_compat_netbsd.h"
83 #endif
84 
85 #include <sys/param.h>
86 #include <sys/time.h>
87 #include <sys/kernel.h>
88 #include <sys/systm.h>
89 #include <sys/sysctl.h>
90 #include <sys/proc.h>
91 #include <sys/buf.h>
92 #include <sys/syslog.h>
93 #include <sys/mount.h>
94 #include <sys/dirent.h>
95 #include <sys/signalvar.h>
96 #include <sys/vnode.h>
97 #include <sys/malloc.h>
98 #include <sys/kauth.h>
99 #include <sys/module.h>
100 
101 #include <miscfs/genfs/genfs.h>
102 
103 #include <miscfs/procfs/procfs.h>
104 
105 #include <uvm/uvm_extern.h>			/* for PAGE_SIZE */
106 
107 MODULE(MODULE_CLASS_VFS, procfs, NULL);
108 
109 VFS_PROTOS(procfs);
110 
111 /*
112  * VFS Operations.
113  *
114  * mount system call
115  */
116 /* ARGSUSED */
117 int
118 procfs_mount(
119     struct mount *mp,
120     const char *path,
121     void *data,
122     size_t *data_len)
123 {
124 	struct lwp *l = curlwp;
125 	struct procfsmount *pmnt;
126 	struct procfs_args *args = data;
127 	int error;
128 
129 	if (UIO_MX & (UIO_MX-1)) {
130 		log(LOG_ERR, "procfs: invalid directory entry size");
131 		return (EINVAL);
132 	}
133 
134 	if (mp->mnt_flag & MNT_GETARGS) {
135 		if (*data_len < sizeof *args)
136 			return EINVAL;
137 
138 		pmnt = VFSTOPROC(mp);
139 		if (pmnt == NULL)
140 			return EIO;
141 		args->version = PROCFS_ARGSVERSION;
142 		args->flags = pmnt->pmnt_flags;
143 		*data_len = sizeof *args;
144 		return 0;
145 	}
146 
147 	if (mp->mnt_flag & MNT_UPDATE)
148 		return (EOPNOTSUPP);
149 
150 	if (*data_len >= sizeof *args && args->version != PROCFS_ARGSVERSION)
151 		return EINVAL;
152 
153 	pmnt = (struct procfsmount *) malloc(sizeof(struct procfsmount),
154 	    M_UFSMNT, M_WAITOK);   /* XXX need new malloc type */
155 
156 	mp->mnt_stat.f_namemax = MAXNAMLEN;
157 	mp->mnt_flag |= MNT_LOCAL;
158 	mp->mnt_data = pmnt;
159 	vfs_getnewfsid(mp);
160 
161 	error = set_statvfs_info(path, UIO_USERSPACE, "procfs", UIO_SYSSPACE,
162 	    mp->mnt_op->vfs_name, mp, l);
163 	pmnt->pmnt_exechook = exechook_establish(procfs_revoke_vnodes, mp);
164 	if (*data_len >= sizeof *args)
165 		pmnt->pmnt_flags = args->flags;
166 	else
167 		pmnt->pmnt_flags = 0;
168 
169 	mp->mnt_iflag |= IMNT_MPSAFE;
170 	return error;
171 }
172 
173 /*
174  * unmount system call
175  */
176 int
177 procfs_unmount(struct mount *mp, int mntflags)
178 {
179 	int error;
180 	int flags = 0;
181 
182 	if (mntflags & MNT_FORCE)
183 		flags |= FORCECLOSE;
184 
185 	if ((error = vflush(mp, 0, flags)) != 0)
186 		return (error);
187 
188 	exechook_disestablish(VFSTOPROC(mp)->pmnt_exechook);
189 
190 	free(mp->mnt_data, M_UFSMNT);
191 	mp->mnt_data = NULL;
192 
193 	return (0);
194 }
195 
196 int
197 procfs_root(mp, vpp)
198 	struct mount *mp;
199 	struct vnode **vpp;
200 {
201 
202 	return (procfs_allocvp(mp, vpp, 0, PFSroot, -1, NULL));
203 }
204 
205 /* ARGSUSED */
206 int
207 procfs_start(struct mount *mp, int flags)
208 {
209 
210 	return (0);
211 }
212 
213 /*
214  * Get file system statistics.
215  */
216 int
217 procfs_statvfs(struct mount *mp, struct statvfs *sbp)
218 {
219 
220 	sbp->f_bsize = PAGE_SIZE;
221 	sbp->f_frsize = PAGE_SIZE;
222 	sbp->f_iosize = PAGE_SIZE;
223 	sbp->f_blocks = 1;	/* avoid divide by zero in some df's */
224 	sbp->f_bfree = 0;
225 	sbp->f_bavail = 0;
226 	sbp->f_bresvd = 0;
227 	sbp->f_files = maxproc;			/* approx */
228 	sbp->f_ffree = maxproc - nprocs;	/* approx */
229 	sbp->f_favail = maxproc - nprocs;	/* approx */
230 	sbp->f_fresvd = 0;
231 	copy_statvfs_info(sbp, mp);
232 	return (0);
233 }
234 
235 /*ARGSUSED*/
236 int
237 procfs_sync(
238     struct mount *mp,
239     int waitfor,
240     kauth_cred_t uc)
241 {
242 
243 	return (0);
244 }
245 
246 /*ARGSUSED*/
247 int
248 procfs_vget(struct mount *mp, ino_t ino,
249     struct vnode **vpp)
250 {
251 	return (EOPNOTSUPP);
252 }
253 
254 void
255 procfs_init()
256 {
257 	procfs_hashinit();
258 }
259 
260 void
261 procfs_reinit()
262 {
263 	procfs_hashreinit();
264 }
265 
266 void
267 procfs_done()
268 {
269 	procfs_hashdone();
270 }
271 
272 SYSCTL_SETUP(sysctl_vfs_procfs_setup, "sysctl vfs.procfs subtree setup")
273 {
274 
275 	sysctl_createv(clog, 0, NULL, NULL,
276 		       CTLFLAG_PERMANENT,
277 		       CTLTYPE_NODE, "vfs", NULL,
278 		       NULL, 0, NULL, 0,
279 		       CTL_VFS, CTL_EOL);
280 	sysctl_createv(clog, 0, NULL, NULL,
281 		       CTLFLAG_PERMANENT,
282 		       CTLTYPE_NODE, "procfs",
283 		       SYSCTL_DESCR("Process file system"),
284 		       NULL, 0, NULL, 0,
285 		       CTL_VFS, 12, CTL_EOL);
286 	/*
287 	 * XXX the "12" above could be dynamic, thereby eliminating
288 	 * one more instance of the "number to vfs" mapping problem,
289 	 * but "12" is the order as taken from sys/mount.h
290 	 */
291 }
292 
293 extern const struct vnodeopv_desc procfs_vnodeop_opv_desc;
294 
295 const struct vnodeopv_desc * const procfs_vnodeopv_descs[] = {
296 	&procfs_vnodeop_opv_desc,
297 	NULL,
298 };
299 
300 struct vfsops procfs_vfsops = {
301 	MOUNT_PROCFS,
302 	sizeof (struct procfs_args),
303 	procfs_mount,
304 	procfs_start,
305 	procfs_unmount,
306 	procfs_root,
307 	(void *)eopnotsupp,		/* vfs_quotactl */
308 	procfs_statvfs,
309 	procfs_sync,
310 	procfs_vget,
311 	(void *)eopnotsupp,		/* vfs_fhtovp */
312 	(void *)eopnotsupp,		/* vfs_vptofh */
313 	procfs_init,
314 	procfs_reinit,
315 	procfs_done,
316 	NULL,				/* vfs_mountroot */
317 	(int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
318 	vfs_stdextattrctl,
319 	(void *)eopnotsupp,		/* vfs_suspendctl */
320 	genfs_renamelock_enter,
321 	genfs_renamelock_exit,
322 	(void *)eopnotsupp,
323 	procfs_vnodeopv_descs,
324 	0,
325 	{ NULL, NULL },
326 };
327 
328 static int
329 procfs_modcmd(modcmd_t cmd, void *arg)
330 {
331 
332 	switch (cmd) {
333 	case MODULE_CMD_INIT:
334 		return vfs_attach(&procfs_vfsops);
335 	case MODULE_CMD_FINI:
336 		return vfs_detach(&procfs_vfsops);
337 	default:
338 		return ENOTTY;
339 	}
340 }
341