umap_vfsops.c revision 1.39.2.6 1 /* $NetBSD: umap_vfsops.c,v 1.39.2.6 2005/01/17 19:32:38 skrll 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. 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 * from: @(#)null_vfsops.c 1.5 (Berkeley) 7/10/92
35 * @(#)umap_vfsops.c 8.8 (Berkeley) 5/14/95
36 */
37
38 /*
39 * Umap Layer
40 * (See mount_umap(8) for a description of this layer.)
41 */
42
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.39.2.6 2005/01/17 19:32:38 skrll Exp $");
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/sysctl.h>
49 #include <sys/proc.h>
50 #include <sys/time.h>
51 #include <sys/vnode.h>
52 #include <sys/mount.h>
53 #include <sys/namei.h>
54 #include <sys/malloc.h>
55 #include <miscfs/umapfs/umap.h>
56 #include <miscfs/genfs/layer_extern.h>
57
58 int umapfs_mount __P((struct mount *, const char *, void *,
59 struct nameidata *, struct lwp *));
60 int umapfs_unmount __P((struct mount *, int, struct lwp *));
61
62 /*
63 * Mount umap layer
64 */
65 int
66 umapfs_mount(mp, path, data, ndp, l)
67 struct mount *mp;
68 const char *path;
69 void *data;
70 struct nameidata *ndp;
71 struct lwp *l;
72 {
73 struct umap_args args;
74 struct vnode *lowerrootvp, *vp;
75 struct umap_mount *amp;
76 struct proc *p = l->l_proc;
77 int error;
78 #ifdef UMAPFS_DIAGNOSTIC
79 int i;
80 #endif
81
82 if (mp->mnt_flag & MNT_GETARGS) {
83 amp = MOUNTTOUMAPMOUNT(mp);
84 if (amp == NULL)
85 return EIO;
86 args.la.target = NULL;
87 vfs_showexport(mp, &args.la.export, &->umapm_export);
88 args.nentries = amp->info_nentries;
89 args.gnentries = amp->info_gnentries;
90 return copyout(&args, data, sizeof(args));
91 }
92
93 /* only for root */
94 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
95 return error;
96
97 #ifdef UMAPFS_DIAGNOSTIC
98 printf("umapfs_mount(mp = %p)\n", mp);
99 #endif
100
101 /*
102 * Get argument
103 */
104 error = copyin(data, &args, sizeof(struct umap_args));
105 if (error)
106 return (error);
107
108 /*
109 * Update only does export updating.
110 */
111 if (mp->mnt_flag & MNT_UPDATE) {
112 amp = MOUNTTOUMAPMOUNT(mp);
113 if (args.umap_target == 0)
114 return (vfs_export(mp, &->umapm_export,
115 &args.umap_export));
116 else
117 return (EOPNOTSUPP);
118 }
119
120 /*
121 * Find lower node
122 */
123 NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF,
124 UIO_USERSPACE, args.umap_target, l);
125 if ((error = namei(ndp)) != 0)
126 return (error);
127
128 /*
129 * Sanity check on lower vnode
130 */
131 lowerrootvp = ndp->ni_vp;
132 #ifdef UMAPFS_DIAGNOSTIC
133 printf("vp = %p, check for VDIR...\n", lowerrootvp);
134 #endif
135
136 if (lowerrootvp->v_type != VDIR) {
137 vput(lowerrootvp);
138 return (EINVAL);
139 }
140
141 #ifdef UMAPFS_DIAGNOSTIC
142 printf("mp = %p\n", mp);
143 #endif
144
145 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount),
146 M_UFSMNT, M_WAITOK); /* XXX */
147 memset(amp, 0, sizeof(struct umap_mount));
148
149 mp->mnt_data = amp;
150 mp->mnt_leaf = lowerrootvp->v_mount->mnt_leaf;
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, 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, 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_statvfs_info(path, UIO_USERSPACE, args.umap_target,
234 UIO_USERSPACE, mp, l);
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, l)
247 struct mount *mp;
248 int mntflags;
249 struct lwp *l;
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 SYSCTL_SETUP(sysctl_vfs_umap_setup, "sysctl vfs.umap subtree setup")
297 {
298
299 sysctl_createv(clog, 0, NULL, NULL,
300 CTLFLAG_PERMANENT,
301 CTLTYPE_NODE, "vfs", NULL,
302 NULL, 0, NULL, 0,
303 CTL_VFS, CTL_EOL);
304 sysctl_createv(clog, 0, NULL, NULL,
305 CTLFLAG_PERMANENT,
306 CTLTYPE_NODE, "umap",
307 SYSCTL_DESCR("UID/GID remapping file system"),
308 NULL, 0, NULL, 0,
309 CTL_VFS, 10, CTL_EOL);
310 /*
311 * XXX the "10" above could be dynamic, thereby eliminating
312 * one more instance of the "number to vfs" mapping problem,
313 * but "10" is the order as taken from sys/mount.h
314 */
315 }
316
317 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc;
318
319 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = {
320 &umapfs_vnodeop_opv_desc,
321 NULL,
322 };
323
324 struct vfsops umapfs_vfsops = {
325 MOUNT_UMAP,
326 umapfs_mount,
327 layerfs_start,
328 umapfs_unmount,
329 layerfs_root,
330 layerfs_quotactl,
331 layerfs_statvfs,
332 layerfs_sync,
333 layerfs_vget,
334 layerfs_fhtovp,
335 layerfs_vptofh,
336 layerfs_init,
337 NULL,
338 layerfs_done,
339 NULL,
340 NULL, /* vfs_mountroot */
341 layerfs_checkexp,
342 layerfs_snapshot,
343 vfs_stdextattrctl,
344 umapfs_vnodeopv_descs,
345 };
346