umap_vfsops.c revision 1.26 1 /* $NetBSD: umap_vfsops.c,v 1.26 2000/11/08 14:28:14 ad 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/param.h>
48 #include <sys/systm.h>
49 #include <sys/proc.h>
50 #include <sys/time.h>
51 #include <sys/types.h>
52 #include <sys/vnode.h>
53 #include <sys/mount.h>
54 #include <sys/namei.h>
55 #include <sys/malloc.h>
56 #include <miscfs/umapfs/umap.h>
57 #include <miscfs/genfs/layer_extern.h>
58
59 int umapfs_mount __P((struct mount *, const char *, void *,
60 struct nameidata *, struct proc *));
61 int umapfs_unmount __P((struct mount *, int, struct proc *));
62
63 /*
64 * Mount umap layer
65 */
66 int
67 umapfs_mount(mp, path, data, ndp, p)
68 struct mount *mp;
69 const char *path;
70 void *data;
71 struct nameidata *ndp;
72 struct proc *p;
73 {
74 struct umap_args args;
75 struct vnode *lowerrootvp, *vp;
76 struct umap_mount *amp;
77 size_t size;
78 int error;
79 #ifdef UMAPFS_DIAGNOSTIC
80 int i;
81 #endif
82
83 /* only for root */
84 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
85 return error;
86
87 #ifdef UMAPFS_DIAGNOSTIC
88 printf("umapfs_mount(mp = %p)\n", mp);
89 #endif
90
91 /*
92 * Get argument
93 */
94 error = copyin(data, (caddr_t)&args, sizeof(struct umap_args));
95 if (error)
96 return (error);
97
98 /*
99 * Update only does export updating.
100 */
101 if (mp->mnt_flag & MNT_UPDATE) {
102 amp = MOUNTTOUMAPMOUNT(mp);
103 if (args.umap_target == 0)
104 return (vfs_export(mp, &->umapm_export,
105 &args.umap_export));
106 else
107 return (EOPNOTSUPP);
108 }
109
110 /*
111 * Find lower node
112 */
113 NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF,
114 UIO_USERSPACE, args.umap_target, p);
115 if ((error = namei(ndp)) != 0)
116 return (error);
117
118 /*
119 * Sanity check on lower vnode
120 */
121 lowerrootvp = ndp->ni_vp;
122 #ifdef UMAPFS_DIAGNOSTIC
123 printf("vp = %p, check for VDIR...\n", lowerrootvp);
124 #endif
125 vrele(ndp->ni_dvp);
126 ndp->ni_dvp = 0;
127
128 if (lowerrootvp->v_type != VDIR) {
129 vput(lowerrootvp);
130 return (EINVAL);
131 }
132
133 #ifdef UMAPFS_DIAGNOSTIC
134 printf("mp = %p\n", mp);
135 #endif
136
137 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount),
138 M_UFSMNT, M_WAITOK); /* XXX */
139 memset((caddr_t)amp, 0, sizeof(struct umap_mount));
140
141 mp->mnt_data = (qaddr_t) amp;
142 amp->umapm_vfs = lowerrootvp->v_mount;
143 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL)
144 mp->mnt_flag |= MNT_LOCAL;
145
146 /*
147 * Now copy in the number of entries and maps for umap mapping.
148 */
149 amp->info_nentries = args.nentries;
150 amp->info_gnentries = args.gnentries;
151 error = copyin(args.mapdata, (caddr_t)amp->info_mapdata,
152 2*sizeof(u_long)*args.nentries);
153 if (error) {
154 vput(lowerrootvp);
155 return (error);
156 }
157
158 #ifdef UMAPFS_DIAGNOSTIC
159 printf("umap_mount:nentries %d\n",args.nentries);
160 for (i = 0; i < args.nentries; i++)
161 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0],
162 amp->info_mapdata[i][1]);
163 #endif
164
165 error = copyin(args.gmapdata, (caddr_t)amp->info_gmapdata,
166 2*sizeof(u_long)*args.gnentries);
167 if (error) {
168 vput(lowerrootvp);
169 return (error);
170 }
171
172 #ifdef UMAPFS_DIAGNOSTIC
173 printf("umap_mount:gnentries %d\n",args.gnentries);
174 for (i = 0; i < args.gnentries; i++)
175 printf("\tgroup %ld maps to %ld\n",
176 amp->info_gmapdata[i][0],
177 amp->info_gmapdata[i][1]);
178 #endif
179
180 /*
181 * Make sure the mount point's sufficiently initialized
182 * that the node create call will work.
183 */
184 vfs_getnewfsid(mp);
185 amp->umapm_size = sizeof(struct umap_node);
186 amp->umapm_tag = VT_UMAP;
187 amp->umapm_bypass = umap_bypass;
188 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */
189 amp->umapm_vnodeop_p = umap_vnodeop_p;
190 simple_lock_init(&->umapm_hashlock);
191 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE,
192 M_WAITOK, &->umapm_node_hash);
193
194
195 /*
196 * fix up umap node for root vnode.
197 */
198 error = layer_node_create(mp, lowerrootvp, &vp);
199 /*
200 * Make sure the node alias worked
201 */
202 if (error) {
203 vput(lowerrootvp);
204 free(amp, M_UFSMNT); /* XXX */
205 return (error);
206 }
207 /*
208 * Unlock the node (either the lower or the alias)
209 */
210 VOP_UNLOCK(vp, 0);
211
212 /*
213 * Keep a held reference to the root vnode.
214 * It is vrele'd in umapfs_unmount.
215 */
216 vp->v_flag |= VROOT;
217 amp->umapm_rootvp = vp;
218
219 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
220 memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size);
221 (void) copyinstr(args.umap_target, mp->mnt_stat.f_mntfromname,
222 MNAMELEN - 1, &size);
223 memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size);
224 #ifdef UMAPFS_DIAGNOSTIC
225 printf("umapfs_mount: lower %s, alias at %s\n",
226 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
227 #endif
228 return (0);
229 }
230
231 /*
232 * Free reference to umap layer
233 */
234 int
235 umapfs_unmount(mp, mntflags, p)
236 struct mount *mp;
237 int mntflags;
238 struct proc *p;
239 {
240 struct vnode *rootvp = MOUNTTOUMAPMOUNT(mp)->umapm_rootvp;
241 int error;
242 int flags = 0;
243
244 #ifdef UMAPFS_DIAGNOSTIC
245 printf("umapfs_unmount(mp = %p)\n", mp);
246 #endif
247
248 if (mntflags & MNT_FORCE)
249 flags |= FORCECLOSE;
250
251 /*
252 * Clear out buffer cache. I don't think we
253 * ever get anything cached at this level at the
254 * moment, but who knows...
255 */
256 #ifdef notyet
257 mntflushbuf(mp, 0);
258 if (mntinvalbuf(mp, 1))
259 return (EBUSY);
260 #endif
261 if (rootvp->v_usecount > 1)
262 return (EBUSY);
263 if ((error = vflush(mp, rootvp, flags)) != 0)
264 return (error);
265
266 #ifdef UMAPFS_DIAGNOSTIC
267 vprint("alias root of lower", rootvp);
268 #endif
269 /*
270 * Release reference on underlying root vnode
271 */
272 vrele(rootvp);
273 /*
274 * And blow it away for future re-use
275 */
276 vgone(rootvp);
277 /*
278 * Finally, throw away the umap_mount structure
279 */
280 free(mp->mnt_data, M_UFSMNT); /* XXX */
281 mp->mnt_data = 0;
282 return (0);
283 }
284
285 extern struct vnodeopv_desc umapfs_vnodeop_opv_desc;
286
287 struct vnodeopv_desc *umapfs_vnodeopv_descs[] = {
288 &umapfs_vnodeop_opv_desc,
289 NULL,
290 };
291
292 struct vfsops umapfs_vfsops = {
293 MOUNT_UMAP,
294 umapfs_mount,
295 layerfs_start,
296 umapfs_unmount,
297 layerfs_root,
298 layerfs_quotactl,
299 layerfs_statfs,
300 layerfs_sync,
301 layerfs_vget,
302 layerfs_fhtovp,
303 layerfs_vptofh,
304 layerfs_init,
305 layerfs_done,
306 layerfs_sysctl,
307 NULL, /* vfs_mountroot */
308 layerfs_checkexp,
309 umapfs_vnodeopv_descs,
310 };
311