kernfs_vfsops.c revision 1.89 1 /* $NetBSD: kernfs_vfsops.c,v 1.89 2009/03/15 17:22:38 cegger 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 1.89 2009/03/15 17:22:38 cegger 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(void)
80 {
81
82 malloc_type_attach(M_KERNFSMNT);
83 kernfs_hashinit();
84 }
85
86 void
87 kernfs_reinit(void)
88 {
89 kernfs_hashreinit();
90 }
91
92 void
93 kernfs_done(void)
94 {
95
96 kernfs_hashdone();
97 malloc_type_detach(M_KERNFSMNT);
98 }
99
100 void
101 kernfs_get_rrootdev(void)
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 fmp = malloc(sizeof(struct kernfs_mount), M_KERNFSMNT, M_WAITOK|M_ZERO);
146 TAILQ_INIT(&fmp->nodelist);
147
148 mp->mnt_stat.f_namemax = MAXNAMLEN;
149 mp->mnt_flag |= MNT_LOCAL;
150 mp->mnt_data = fmp;
151 vfs_getnewfsid(mp);
152
153 if ((error = set_statvfs_info(path, UIO_USERSPACE, "kernfs",
154 UIO_SYSSPACE, mp->mnt_op->vfs_name, mp, l)) != 0) {
155 free(fmp, M_KERNFSMNT);
156 return error;
157 }
158
159 kernfs_get_rrootdev();
160 return 0;
161 }
162
163 int
164 kernfs_start(struct mount *mp, int flags)
165 {
166
167 return (0);
168 }
169
170 int
171 kernfs_unmount(struct mount *mp, int mntflags)
172 {
173 int error;
174 int flags = 0;
175
176 if (mntflags & MNT_FORCE)
177 flags |= FORCECLOSE;
178
179 if ((error = vflush(mp, 0, flags)) != 0)
180 return (error);
181
182 /*
183 * Finally, throw away the kernfs_mount structure
184 */
185 free(mp->mnt_data, M_KERNFSMNT);
186 mp->mnt_data = NULL;
187 return (0);
188 }
189
190 int
191 kernfs_root(struct mount *mp, struct vnode **vpp)
192 {
193
194 /* setup "." */
195 return (kernfs_allocvp(mp, vpp, KFSkern, &kern_targets[0], 0));
196 }
197
198 int
199 kernfs_statvfs(struct mount *mp, struct statvfs *sbp)
200 {
201
202 sbp->f_bsize = DEV_BSIZE;
203 sbp->f_frsize = DEV_BSIZE;
204 sbp->f_iosize = DEV_BSIZE;
205 sbp->f_blocks = 2; /* 1K to keep df happy */
206 sbp->f_bfree = 0;
207 sbp->f_bavail = 0;
208 sbp->f_bresvd = 0;
209 sbp->f_files = 1024; /* XXX lie */
210 sbp->f_ffree = 128; /* XXX lie */
211 sbp->f_favail = 128; /* XXX lie */
212 sbp->f_fresvd = 0;
213 copy_statvfs_info(sbp, mp);
214 return (0);
215 }
216
217 /*ARGSUSED*/
218 int
219 kernfs_sync(struct mount *mp, int waitfor,
220 kauth_cred_t uc)
221 {
222
223 return (0);
224 }
225
226 /*
227 * Kernfs flat namespace lookup.
228 * Currently unsupported.
229 */
230 int
231 kernfs_vget(struct mount *mp, ino_t ino,
232 struct vnode **vpp)
233 {
234
235 return (EOPNOTSUPP);
236 }
237
238 extern const struct vnodeopv_desc kernfs_vnodeop_opv_desc;
239
240 const struct vnodeopv_desc * const kernfs_vnodeopv_descs[] = {
241 &kernfs_vnodeop_opv_desc,
242 NULL,
243 };
244
245 struct vfsops kernfs_vfsops = {
246 MOUNT_KERNFS,
247 0,
248 kernfs_mount,
249 kernfs_start,
250 kernfs_unmount,
251 kernfs_root,
252 (void *)eopnotsupp, /* vfs_quotactl */
253 kernfs_statvfs,
254 kernfs_sync,
255 kernfs_vget,
256 (void *)eopnotsupp, /* vfs_fhtovp */
257 (void *)eopnotsupp, /* vfs_vptofh */
258 kernfs_init,
259 kernfs_reinit,
260 kernfs_done,
261 NULL, /* vfs_mountroot */
262 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
263 vfs_stdextattrctl,
264 (void *)eopnotsupp, /* vfs_suspendctl */
265 genfs_renamelock_enter,
266 genfs_renamelock_exit,
267 (void *)eopnotsupp,
268 kernfs_vnodeopv_descs,
269 0,
270 { NULL, NULL },
271 };
272
273 static int
274 kernfs_modcmd(modcmd_t cmd, void *arg)
275 {
276 int error;
277
278 switch (cmd) {
279 case MODULE_CMD_INIT:
280 error = vfs_attach(&kernfs_vfsops);
281 if (error != 0)
282 break;
283 sysctl_createv(&kernfs_sysctl_log, 0, NULL, NULL,
284 CTLFLAG_PERMANENT,
285 CTLTYPE_NODE, "vfs", NULL,
286 NULL, 0, NULL, 0,
287 CTL_VFS, CTL_EOL);
288 sysctl_createv(&kernfs_sysctl_log, 0, NULL, NULL,
289 CTLFLAG_PERMANENT,
290 CTLTYPE_NODE, "kernfs",
291 SYSCTL_DESCR("/kern file system"),
292 NULL, 0, NULL, 0,
293 CTL_VFS, 11, CTL_EOL);
294 /*
295 * XXX the "11" above could be dynamic, thereby eliminating one
296 * more instance of the "number to vfs" mapping problem, but
297 * "11" is the order as taken from sys/mount.h
298 */
299 break;
300 case MODULE_CMD_FINI:
301 error = vfs_detach(&kernfs_vfsops);
302 if (error != 0)
303 break;
304 sysctl_teardown(&kernfs_sysctl_log);
305 break;
306 default:
307 error = ENOTTY;
308 break;
309 }
310
311 return (error);
312 }
313