kernfs_vfsops.c revision 1.83.6.2 1 /* $NetBSD: kernfs_vfsops.c,v 1.83.6.2 2008/06/29 09:33:16 mjf 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. 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 * @(#)kernfs_vfsops.c 8.10 (Berkeley) 5/14/95
35 */
36
37 /*
38 * Kernel params Filesystem
39 */
40
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: kernfs_vfsops.c,v 1.83.6.2 2008/06/29 09:33:16 mjf Exp $");
43
44 #ifdef _KERNEL_OPT
45 #include "opt_compat_netbsd.h"
46 #endif
47
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/sysctl.h>
51 #include <sys/conf.h>
52 #include <sys/proc.h>
53 #include <sys/vnode.h>
54 #include <sys/mount.h>
55 #include <sys/namei.h>
56 #include <sys/dirent.h>
57 #include <sys/malloc.h>
58 #include <sys/syslog.h>
59 #include <sys/kauth.h>
60 #include <sys/module.h>
61
62 #include <miscfs/genfs/genfs.h>
63 #include <miscfs/specfs/specdev.h>
64 #include <miscfs/kernfs/kernfs.h>
65
66 MODULE(MODULE_CLASS_VFS, kernfs, NULL);
67
68 MALLOC_JUSTDEFINE(M_KERNFSMNT, "kernfs mount", "kernfs mount structures");
69
70 dev_t rrootdev = NODEV;
71
72 VFS_PROTOS(kernfs);
73
74 void kernfs_get_rrootdev(void);
75
76 static struct sysctllog *kernfs_sysctl_log;
77
78 void
79 kernfs_init()
80 {
81
82 malloc_type_attach(M_KERNFSMNT);
83 kernfs_hashinit();
84 }
85
86 void
87 kernfs_reinit()
88 {
89 kernfs_hashreinit();
90 }
91
92 void
93 kernfs_done()
94 {
95
96 kernfs_hashdone();
97 malloc_type_detach(M_KERNFSMNT);
98 }
99
100 void
101 kernfs_get_rrootdev()
102 {
103 static int tried = 0;
104
105 if (tried) {
106 /* Already did it once. */
107 return;
108 }
109 tried = 1;
110
111 if (rootdev == NODEV)
112 return;
113 rrootdev = devsw_blk2chr(rootdev);
114 if (rrootdev != NODEV)
115 return;
116 rrootdev = NODEV;
117 printf("kernfs_get_rrootdev: no raw root device\n");
118 }
119
120 /*
121 * Mount the Kernel params filesystem
122 */
123 int
124 kernfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len)
125 {
126 struct lwp *l = curlwp;
127 int error = 0;
128 struct kernfs_mount *fmp;
129
130 if (UIO_MX & (UIO_MX - 1)) {
131 log(LOG_ERR, "kernfs: invalid directory entry size");
132 return (EINVAL);
133 }
134
135 if (mp->mnt_flag & MNT_GETARGS) {
136 *data_len = 0;
137 return 0;
138 }
139 /*
140 * Update is a no-op
141 */
142 if (mp->mnt_flag & MNT_UPDATE)
143 return (EOPNOTSUPP);
144
145 MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
146 M_KERNFSMNT, M_WAITOK);
147 memset(fmp, 0, sizeof(*fmp));
148 TAILQ_INIT(&fmp->nodelist);
149
150 mp->mnt_stat.f_namemax = MAXNAMLEN;
151 mp->mnt_flag |= MNT_LOCAL;
152 mp->mnt_data = fmp;
153 vfs_getnewfsid(mp);
154
155 if ((error = set_statvfs_info(path, UIO_USERSPACE, "kernfs",
156 UIO_SYSSPACE, mp->mnt_op->vfs_name, mp, l)) != 0) {
157 free(fmp, M_KERNFSMNT);
158 return error;
159 }
160
161 kernfs_get_rrootdev();
162 return 0;
163 }
164
165 int
166 kernfs_start(struct mount *mp, int flags)
167 {
168
169 return (0);
170 }
171
172 int
173 kernfs_unmount(struct mount *mp, int mntflags)
174 {
175 int error;
176 int flags = 0;
177
178 if (mntflags & MNT_FORCE)
179 flags |= FORCECLOSE;
180
181 if ((error = vflush(mp, 0, flags)) != 0)
182 return (error);
183
184 /*
185 * Finally, throw away the kernfs_mount structure
186 */
187 free(mp->mnt_data, M_KERNFSMNT);
188 mp->mnt_data = NULL;
189 return (0);
190 }
191
192 int
193 kernfs_root(mp, vpp)
194 struct mount *mp;
195 struct vnode **vpp;
196 {
197
198 /* setup "." */
199 return (kernfs_allocvp(mp, vpp, KFSkern, &kern_targets[0], 0));
200 }
201
202 int
203 kernfs_statvfs(struct mount *mp, struct statvfs *sbp)
204 {
205
206 sbp->f_bsize = DEV_BSIZE;
207 sbp->f_frsize = DEV_BSIZE;
208 sbp->f_iosize = DEV_BSIZE;
209 sbp->f_blocks = 2; /* 1K to keep df happy */
210 sbp->f_bfree = 0;
211 sbp->f_bavail = 0;
212 sbp->f_bresvd = 0;
213 sbp->f_files = 1024; /* XXX lie */
214 sbp->f_ffree = 128; /* XXX lie */
215 sbp->f_favail = 128; /* XXX lie */
216 sbp->f_fresvd = 0;
217 copy_statvfs_info(sbp, mp);
218 return (0);
219 }
220
221 /*ARGSUSED*/
222 int
223 kernfs_sync(struct mount *mp, int waitfor,
224 kauth_cred_t uc)
225 {
226
227 return (0);
228 }
229
230 /*
231 * Kernfs flat namespace lookup.
232 * Currently unsupported.
233 */
234 int
235 kernfs_vget(struct mount *mp, ino_t ino,
236 struct vnode **vpp)
237 {
238
239 return (EOPNOTSUPP);
240 }
241
242 extern const struct vnodeopv_desc kernfs_vnodeop_opv_desc;
243
244 const struct vnodeopv_desc * const kernfs_vnodeopv_descs[] = {
245 &kernfs_vnodeop_opv_desc,
246 NULL,
247 };
248
249 struct vfsops kernfs_vfsops = {
250 MOUNT_KERNFS,
251 0,
252 kernfs_mount,
253 kernfs_start,
254 kernfs_unmount,
255 kernfs_root,
256 (void *)eopnotsupp, /* vfs_quotactl */
257 kernfs_statvfs,
258 kernfs_sync,
259 kernfs_vget,
260 (void *)eopnotsupp, /* vfs_fhtovp */
261 (void *)eopnotsupp, /* vfs_vptofh */
262 kernfs_init,
263 kernfs_reinit,
264 kernfs_done,
265 NULL, /* vfs_mountroot */
266 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
267 vfs_stdextattrctl,
268 (void *)eopnotsupp, /* vfs_suspendctl */
269 genfs_renamelock_enter,
270 genfs_renamelock_exit,
271 (void *)eopnotsupp,
272 kernfs_vnodeopv_descs,
273 0,
274 { NULL, NULL },
275 };
276
277 static int
278 kernfs_modcmd(modcmd_t cmd, void *arg)
279 {
280 int error;
281
282 switch (cmd) {
283 case MODULE_CMD_INIT:
284 error = vfs_attach(&kernfs_vfsops);
285 if (error != 0)
286 break;
287 sysctl_createv(&kernfs_sysctl_log, 0, NULL, NULL,
288 CTLFLAG_PERMANENT,
289 CTLTYPE_NODE, "vfs", NULL,
290 NULL, 0, NULL, 0,
291 CTL_VFS, CTL_EOL);
292 sysctl_createv(&kernfs_sysctl_log, 0, NULL, NULL,
293 CTLFLAG_PERMANENT,
294 CTLTYPE_NODE, "kernfs",
295 SYSCTL_DESCR("/kern file system"),
296 NULL, 0, NULL, 0,
297 CTL_VFS, 11, CTL_EOL);
298 /*
299 * XXX the "11" above could be dynamic, thereby eliminating one
300 * more instance of the "number to vfs" mapping problem, but
301 * "11" is the order as taken from sys/mount.h
302 */
303 break;
304 case MODULE_CMD_FINI:
305 error = vfs_detach(&kernfs_vfsops);
306 if (error != 0)
307 break;
308 sysctl_teardown(&kernfs_sysctl_log);
309 break;
310 default:
311 error = ENOTTY;
312 break;
313 }
314
315 return (error);
316 }
317