umap_vfsops.c revision 1.36 1 /* $NetBSD: umap_vfsops.c,v 1.36 2003/04/16 21:44:24 christos Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software donated to Berkeley by
8 * the UCLA Ficus project.
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 * from: @(#)null_vfsops.c 1.5 (Berkeley) 7/10/92
39 * @(#)umap_vfsops.c 8.8 (Berkeley) 5/14/95
40 */
41
42 /*
43 * Umap Layer
44 * (See mount_umap(8) for a description of this layer.)
45 */
46
47 #include <sys/cdefs.h>
48 __KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.36 2003/04/16 21:44:24 christos Exp $");
49
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/time.h>
54 #include <sys/vnode.h>
55 #include <sys/mount.h>
56 #include <sys/namei.h>
57 #include <sys/malloc.h>
58 #include <miscfs/umapfs/umap.h>
59 #include <miscfs/genfs/layer_extern.h>
60
61 int umapfs_mount __P((struct mount *, const char *, void *,
62 struct nameidata *, struct proc *));
63 int umapfs_unmount __P((struct mount *, int, struct proc *));
64
65 /*
66 * Mount umap layer
67 */
68 int
69 umapfs_mount(mp, path, data, ndp, p)
70 struct mount *mp;
71 const char *path;
72 void *data;
73 struct nameidata *ndp;
74 struct proc *p;
75 {
76 struct umap_args args;
77 struct vnode *lowerrootvp, *vp;
78 struct umap_mount *amp;
79 int error;
80 #ifdef UMAPFS_DIAGNOSTIC
81 int i;
82 #endif
83 if (mp->mnt_flag & MNT_GETARGS) {
84 amp = MOUNTTOUMAPMOUNT(mp);
85 if (amp == NULL)
86 return EIO;
87 args.la.target = NULL;
88 vfs_showexport(mp, &args.la.export, &->umapm_export);
89 args.nentries = amp->info_nentries;
90 args.gnentries = amp->info_gnentries;
91 return copyout(&args, data, sizeof(args));
92 }
93
94 /* only for root */
95 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
96 return error;
97
98 #ifdef UMAPFS_DIAGNOSTIC
99 printf("umapfs_mount(mp = %p)\n", mp);
100 #endif
101
102 /*
103 * Get argument
104 */
105 error = copyin(data, (caddr_t)&args, sizeof(struct umap_args));
106 if (error)
107 return (error);
108
109 /*
110 * Update only does export updating.
111 */
112 if (mp->mnt_flag & MNT_UPDATE) {
113 amp = MOUNTTOUMAPMOUNT(mp);
114 if (args.umap_target == 0)
115 return (vfs_export(mp, &->umapm_export,
116 &args.umap_export));
117 else
118 return (EOPNOTSUPP);
119 }
120
121 /*
122 * Find lower node
123 */
124 NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF,
125 UIO_USERSPACE, args.umap_target, p);
126 if ((error = namei(ndp)) != 0)
127 return (error);
128
129 /*
130 * Sanity check on lower vnode
131 */
132 lowerrootvp = ndp->ni_vp;
133 #ifdef UMAPFS_DIAGNOSTIC
134 printf("vp = %p, check for VDIR...\n", lowerrootvp);
135 #endif
136
137 if (lowerrootvp->v_type != VDIR) {
138 vput(lowerrootvp);
139 return (EINVAL);
140 }
141
142 #ifdef UMAPFS_DIAGNOSTIC
143 printf("mp = %p\n", mp);
144 #endif
145
146 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount),
147 M_UFSMNT, M_WAITOK); /* XXX */
148 memset((caddr_t)amp, 0, sizeof(struct umap_mount));
149
150 mp->mnt_data = amp;
151 amp->umapm_vfs = lowerrootvp->v_mount;
152 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL)
153 mp->mnt_flag |= MNT_LOCAL;
154
155 /*
156 * Now copy in the number of entries and maps for umap mapping.
157 */
158 if (args.nentries > MAPFILEENTRIES || args.gnentries > GMAPFILEENTRIES) {
159 vput(lowerrootvp);
160 return (error);
161 }
162
163 amp->info_nentries = args.nentries;
164 amp->info_gnentries = args.gnentries;
165 error = copyin(args.mapdata, (caddr_t)amp->info_mapdata,
166 2*sizeof(u_long)*args.nentries);
167 if (error) {
168 vput(lowerrootvp);
169 return (error);
170 }
171
172 #ifdef UMAPFS_DIAGNOSTIC
173 printf("umap_mount:nentries %d\n",args.nentries);
174 for (i = 0; i < args.nentries; i++)
175 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0],
176 amp->info_mapdata[i][1]);
177 #endif
178
179 error = copyin(args.gmapdata, (caddr_t)amp->info_gmapdata,
180 2*sizeof(u_long)*args.gnentries);
181 if (error) {
182 vput(lowerrootvp);
183 return (error);
184 }
185
186 #ifdef UMAPFS_DIAGNOSTIC
187 printf("umap_mount:gnentries %d\n",args.gnentries);
188 for (i = 0; i < args.gnentries; i++)
189 printf("\tgroup %ld maps to %ld\n",
190 amp->info_gmapdata[i][0],
191 amp->info_gmapdata[i][1]);
192 #endif
193
194 /*
195 * Make sure the mount point's sufficiently initialized
196 * that the node create call will work.
197 */
198 vfs_getnewfsid(mp);
199 amp->umapm_size = sizeof(struct umap_node);
200 amp->umapm_tag = VT_UMAP;
201 amp->umapm_bypass = umap_bypass;
202 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */
203 amp->umapm_vnodeop_p = umap_vnodeop_p;
204 simple_lock_init(&->umapm_hashlock);
205 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE,
206 M_WAITOK, &->umapm_node_hash);
207
208
209 /*
210 * fix up umap node for root vnode.
211 */
212 error = layer_node_create(mp, lowerrootvp, &vp);
213 /*
214 * Make sure the node alias worked
215 */
216 if (error) {
217 vput(lowerrootvp);
218 free(amp, M_UFSMNT); /* XXX */
219 return (error);
220 }
221 /*
222 * Unlock the node (either the lower or the alias)
223 */
224 VOP_UNLOCK(vp, 0);
225
226 /*
227 * Keep a held reference to the root vnode.
228 * It is vrele'd in umapfs_unmount.
229 */
230 vp->v_flag |= VROOT;
231 amp->umapm_rootvp = vp;
232
233 error = set_statfs_info(path, UIO_USERSPACE, args.umap_target,
234 UIO_USERSPACE, mp, p);
235 #ifdef UMAPFS_DIAGNOSTIC
236 printf("umapfs_mount: lower %s, alias at %s\n",
237 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
238 #endif
239 return error;
240 }
241
242 /*
243 * Free reference to umap layer
244 */
245 int
246 umapfs_unmount(mp, mntflags, p)
247 struct mount *mp;
248 int mntflags;
249 struct proc *p;
250 {
251 struct vnode *rootvp = MOUNTTOUMAPMOUNT(mp)->umapm_rootvp;
252 int error;
253 int flags = 0;
254
255 #ifdef UMAPFS_DIAGNOSTIC
256 printf("umapfs_unmount(mp = %p)\n", mp);
257 #endif
258
259 if (mntflags & MNT_FORCE)
260 flags |= FORCECLOSE;
261
262 /*
263 * Clear out buffer cache. I don't think we
264 * ever get anything cached at this level at the
265 * moment, but who knows...
266 */
267 #ifdef notyet
268 mntflushbuf(mp, 0);
269 if (mntinvalbuf(mp, 1))
270 return (EBUSY);
271 #endif
272 if (rootvp->v_usecount > 1)
273 return (EBUSY);
274 if ((error = vflush(mp, rootvp, flags)) != 0)
275 return (error);
276
277 #ifdef UMAPFS_DIAGNOSTIC
278 vprint("alias root of lower", rootvp);
279 #endif
280 /*
281 * Release reference on underlying root vnode
282 */
283 vrele(rootvp);
284 /*
285 * And blow it away for future re-use
286 */
287 vgone(rootvp);
288 /*
289 * Finally, throw away the umap_mount structure
290 */
291 free(mp->mnt_data, M_UFSMNT); /* XXX */
292 mp->mnt_data = 0;
293 return (0);
294 }
295
296 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc;
297
298 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = {
299 &umapfs_vnodeop_opv_desc,
300 NULL,
301 };
302
303 struct vfsops umapfs_vfsops = {
304 MOUNT_UMAP,
305 umapfs_mount,
306 layerfs_start,
307 umapfs_unmount,
308 layerfs_root,
309 layerfs_quotactl,
310 layerfs_statfs,
311 layerfs_sync,
312 layerfs_vget,
313 layerfs_fhtovp,
314 layerfs_vptofh,
315 layerfs_init,
316 NULL,
317 layerfs_done,
318 layerfs_sysctl,
319 NULL, /* vfs_mountroot */
320 layerfs_checkexp,
321 umapfs_vnodeopv_descs,
322 };
323