umap_vfsops.c revision 1.35 1 /* $NetBSD: umap_vfsops.c,v 1.35 2002/09/21 18:09:31 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 1.35 2002/09/21 18:09:31 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 size_t size;
80 int error;
81 #ifdef UMAPFS_DIAGNOSTIC
82 int i;
83 #endif
84 if (mp->mnt_flag & MNT_GETARGS) {
85 amp = MOUNTTOUMAPMOUNT(mp);
86 if (amp == NULL)
87 return EIO;
88 args.la.target = NULL;
89 vfs_showexport(mp, &args.la.export, &->umapm_export);
90 args.nentries = amp->info_nentries;
91 args.gnentries = amp->info_gnentries;
92 return copyout(&args, data, sizeof(args));
93 }
94
95 /* only for root */
96 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
97 return error;
98
99 #ifdef UMAPFS_DIAGNOSTIC
100 printf("umapfs_mount(mp = %p)\n", mp);
101 #endif
102
103 /*
104 * Get argument
105 */
106 error = copyin(data, (caddr_t)&args, sizeof(struct umap_args));
107 if (error)
108 return (error);
109
110 /*
111 * Update only does export updating.
112 */
113 if (mp->mnt_flag & MNT_UPDATE) {
114 amp = MOUNTTOUMAPMOUNT(mp);
115 if (args.umap_target == 0)
116 return (vfs_export(mp, &->umapm_export,
117 &args.umap_export));
118 else
119 return (EOPNOTSUPP);
120 }
121
122 /*
123 * Find lower node
124 */
125 NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF,
126 UIO_USERSPACE, args.umap_target, p);
127 if ((error = namei(ndp)) != 0)
128 return (error);
129
130 /*
131 * Sanity check on lower vnode
132 */
133 lowerrootvp = ndp->ni_vp;
134 #ifdef UMAPFS_DIAGNOSTIC
135 printf("vp = %p, check for VDIR...\n", lowerrootvp);
136 #endif
137
138 if (lowerrootvp->v_type != VDIR) {
139 vput(lowerrootvp);
140 return (EINVAL);
141 }
142
143 #ifdef UMAPFS_DIAGNOSTIC
144 printf("mp = %p\n", mp);
145 #endif
146
147 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount),
148 M_UFSMNT, M_WAITOK); /* XXX */
149 memset((caddr_t)amp, 0, sizeof(struct umap_mount));
150
151 mp->mnt_data = amp;
152 amp->umapm_vfs = lowerrootvp->v_mount;
153 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL)
154 mp->mnt_flag |= MNT_LOCAL;
155
156 /*
157 * Now copy in the number of entries and maps for umap mapping.
158 */
159 if (args.nentries > MAPFILEENTRIES || args.gnentries > GMAPFILEENTRIES) {
160 vput(lowerrootvp);
161 return (error);
162 }
163
164 amp->info_nentries = args.nentries;
165 amp->info_gnentries = args.gnentries;
166 error = copyin(args.mapdata, (caddr_t)amp->info_mapdata,
167 2*sizeof(u_long)*args.nentries);
168 if (error) {
169 vput(lowerrootvp);
170 return (error);
171 }
172
173 #ifdef UMAPFS_DIAGNOSTIC
174 printf("umap_mount:nentries %d\n",args.nentries);
175 for (i = 0; i < args.nentries; i++)
176 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0],
177 amp->info_mapdata[i][1]);
178 #endif
179
180 error = copyin(args.gmapdata, (caddr_t)amp->info_gmapdata,
181 2*sizeof(u_long)*args.gnentries);
182 if (error) {
183 vput(lowerrootvp);
184 return (error);
185 }
186
187 #ifdef UMAPFS_DIAGNOSTIC
188 printf("umap_mount:gnentries %d\n",args.gnentries);
189 for (i = 0; i < args.gnentries; i++)
190 printf("\tgroup %ld maps to %ld\n",
191 amp->info_gmapdata[i][0],
192 amp->info_gmapdata[i][1]);
193 #endif
194
195 /*
196 * Make sure the mount point's sufficiently initialized
197 * that the node create call will work.
198 */
199 vfs_getnewfsid(mp);
200 amp->umapm_size = sizeof(struct umap_node);
201 amp->umapm_tag = VT_UMAP;
202 amp->umapm_bypass = umap_bypass;
203 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */
204 amp->umapm_vnodeop_p = umap_vnodeop_p;
205 simple_lock_init(&->umapm_hashlock);
206 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE,
207 M_WAITOK, &->umapm_node_hash);
208
209
210 /*
211 * fix up umap node for root vnode.
212 */
213 error = layer_node_create(mp, lowerrootvp, &vp);
214 /*
215 * Make sure the node alias worked
216 */
217 if (error) {
218 vput(lowerrootvp);
219 free(amp, M_UFSMNT); /* XXX */
220 return (error);
221 }
222 /*
223 * Unlock the node (either the lower or the alias)
224 */
225 VOP_UNLOCK(vp, 0);
226
227 /*
228 * Keep a held reference to the root vnode.
229 * It is vrele'd in umapfs_unmount.
230 */
231 vp->v_flag |= VROOT;
232 amp->umapm_rootvp = vp;
233
234 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
235 memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size);
236 (void) copyinstr(args.umap_target, mp->mnt_stat.f_mntfromname,
237 MNAMELEN - 1, &size);
238 memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size);
239 #ifdef UMAPFS_DIAGNOSTIC
240 printf("umapfs_mount: lower %s, alias at %s\n",
241 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
242 #endif
243 return (0);
244 }
245
246 /*
247 * Free reference to umap layer
248 */
249 int
250 umapfs_unmount(mp, mntflags, p)
251 struct mount *mp;
252 int mntflags;
253 struct proc *p;
254 {
255 struct vnode *rootvp = MOUNTTOUMAPMOUNT(mp)->umapm_rootvp;
256 int error;
257 int flags = 0;
258
259 #ifdef UMAPFS_DIAGNOSTIC
260 printf("umapfs_unmount(mp = %p)\n", mp);
261 #endif
262
263 if (mntflags & MNT_FORCE)
264 flags |= FORCECLOSE;
265
266 /*
267 * Clear out buffer cache. I don't think we
268 * ever get anything cached at this level at the
269 * moment, but who knows...
270 */
271 #ifdef notyet
272 mntflushbuf(mp, 0);
273 if (mntinvalbuf(mp, 1))
274 return (EBUSY);
275 #endif
276 if (rootvp->v_usecount > 1)
277 return (EBUSY);
278 if ((error = vflush(mp, rootvp, flags)) != 0)
279 return (error);
280
281 #ifdef UMAPFS_DIAGNOSTIC
282 vprint("alias root of lower", rootvp);
283 #endif
284 /*
285 * Release reference on underlying root vnode
286 */
287 vrele(rootvp);
288 /*
289 * And blow it away for future re-use
290 */
291 vgone(rootvp);
292 /*
293 * Finally, throw away the umap_mount structure
294 */
295 free(mp->mnt_data, M_UFSMNT); /* XXX */
296 mp->mnt_data = 0;
297 return (0);
298 }
299
300 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc;
301
302 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = {
303 &umapfs_vnodeop_opv_desc,
304 NULL,
305 };
306
307 struct vfsops umapfs_vfsops = {
308 MOUNT_UMAP,
309 umapfs_mount,
310 layerfs_start,
311 umapfs_unmount,
312 layerfs_root,
313 layerfs_quotactl,
314 layerfs_statfs,
315 layerfs_sync,
316 layerfs_vget,
317 layerfs_fhtovp,
318 layerfs_vptofh,
319 layerfs_init,
320 NULL,
321 layerfs_done,
322 layerfs_sysctl,
323 NULL, /* vfs_mountroot */
324 layerfs_checkexp,
325 umapfs_vnodeopv_descs,
326 };
327