proc->thread stage 5: BUF/VFS clearance! Remove the ucred argument from
[dragonfly.git] / sys / vfs / nullfs / null_vfsops.c
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1/*
2 * Copyright (c) 1992, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software donated to Berkeley by
6 * Jan-Simon Pendry.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * @(#)null_vfsops.c 8.2 (Berkeley) 1/21/94
37 *
38 * @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92
39 * $FreeBSD: src/sys/miscfs/nullfs/null_vfsops.c,v 1.35.2.3 2001/07/26 20:37:11 iedowse Exp $
3b568787 40 * $DragonFly: src/sys/vfs/nullfs/null_vfsops.c,v 1.4 2003/06/26 05:55:15 dillon Exp $
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41 */
42
43/*
44 * Null Layer
45 * (See null_vnops.c for a description of what this does.)
46 */
47
48#include <sys/param.h>
49#include <sys/systm.h>
50#include <sys/kernel.h>
51#include <sys/proc.h>
52#include <sys/malloc.h>
53#include <sys/vnode.h>
54#include <sys/mount.h>
55#include <sys/namei.h>
56#include <miscfs/nullfs/null.h>
57
58static MALLOC_DEFINE(M_NULLFSMNT, "NULLFS mount", "NULLFS mount structure");
59
60static int nullfs_fhtovp(struct mount *mp, struct fid *fidp,
61 struct vnode **vpp);
62static int nullfs_checkexp(struct mount *mp, struct sockaddr *nam,
63 int *extflagsp, struct ucred **credanonp);
64static int nullfs_mount(struct mount *mp, char *path, caddr_t data,
dadab5e9 65 struct nameidata *ndp, struct thread *td);
984263bc 66static int nullfs_quotactl(struct mount *mp, int cmd, uid_t uid,
dadab5e9 67 caddr_t arg, struct thread *td);
984263bc 68static int nullfs_root(struct mount *mp, struct vnode **vpp);
dadab5e9 69static int nullfs_start(struct mount *mp, int flags, struct thread *td);
984263bc 70static int nullfs_statfs(struct mount *mp, struct statfs *sbp,
dadab5e9 71 struct thread *td);
3b568787 72static int nullfs_sync(struct mount *mp, int waitfor, struct thread *td);
dadab5e9 73static int nullfs_unmount(struct mount *mp, int mntflags, struct thread *td);
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74static int nullfs_vget(struct mount *mp, ino_t ino, struct vnode **vpp);
75static int nullfs_vptofh(struct vnode *vp, struct fid *fhp);
76static int nullfs_extattrctl(struct mount *mp, int cmd,
dadab5e9 77 const char *attrname, caddr_t arg, struct thread *td);
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78
79/*
80 * Mount null layer
81 */
82static int
dadab5e9 83nullfs_mount(mp, path, data, ndp, td)
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84 struct mount *mp;
85 char *path;
86 caddr_t data;
87 struct nameidata *ndp;
dadab5e9 88 struct thread *td;
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89{
90 int error = 0;
91 struct null_args args;
92 struct vnode *lowerrootvp, *vp;
93 struct vnode *nullm_rootvp;
94 struct null_mount *xmp;
95 u_int size;
96 int isvnunlocked = 0;
97
98 NULLFSDEBUG("nullfs_mount(mp = %p)\n", (void *)mp);
99
100 /*
101 * Update is a no-op
102 */
103 if (mp->mnt_flag & MNT_UPDATE) {
104 return (EOPNOTSUPP);
105 /* return VFS_MOUNT(MOUNTTONULLMOUNT(mp)->nullm_vfs, path, data, ndp, p);*/
106 }
107
108 /*
109 * Get argument
110 */
111 error = copyin(data, (caddr_t)&args, sizeof(struct null_args));
112 if (error)
113 return (error);
114
115 /*
116 * Unlock lower node to avoid deadlock.
117 * (XXX) VOP_ISLOCKED is needed?
118 */
119 if ((mp->mnt_vnodecovered->v_op == null_vnodeop_p) &&
120 VOP_ISLOCKED(mp->mnt_vnodecovered, NULL)) {
dadab5e9 121 VOP_UNLOCK(mp->mnt_vnodecovered, 0, td);
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122 isvnunlocked = 1;
123 }
124 /*
125 * Find lower node
126 */
127 NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF,
dadab5e9 128 UIO_USERSPACE, args.target, td);
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129 error = namei(ndp);
130 /*
131 * Re-lock vnode.
132 */
133 if (isvnunlocked && !VOP_ISLOCKED(mp->mnt_vnodecovered, NULL))
dadab5e9 134 vn_lock(mp->mnt_vnodecovered, LK_EXCLUSIVE | LK_RETRY, td);
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135
136 if (error)
137 return (error);
138 NDFREE(ndp, NDF_ONLY_PNBUF);
139
140 /*
141 * Sanity check on lower vnode
142 */
143 lowerrootvp = ndp->ni_vp;
144
145 vrele(ndp->ni_dvp);
146 ndp->ni_dvp = NULLVP;
147
148 /*
149 * Check multi null mount to avoid `lock against myself' panic.
150 */
151 if (lowerrootvp == VTONULL(mp->mnt_vnodecovered)->null_lowervp) {
152 NULLFSDEBUG("nullfs_mount: multi null mount?\n");
153 vput(lowerrootvp);
154 return (EDEADLK);
155 }
156
157 xmp = (struct null_mount *) malloc(sizeof(struct null_mount),
158 M_NULLFSMNT, M_WAITOK); /* XXX */
159
160 /*
161 * Save reference to underlying FS
162 */
163 xmp->nullm_vfs = lowerrootvp->v_mount;
164
165 /*
166 * Save reference. Each mount also holds
167 * a reference on the root vnode.
168 */
169 error = null_node_create(mp, lowerrootvp, &vp);
170 /*
171 * Unlock the node (either the lower or the alias)
172 */
dadab5e9 173 VOP_UNLOCK(vp, 0, td);
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174 /*
175 * Make sure the node alias worked
176 */
177 if (error) {
178 vrele(lowerrootvp);
179 free(xmp, M_NULLFSMNT); /* XXX */
180 return (error);
181 }
182
183 /*
184 * Keep a held reference to the root vnode.
185 * It is vrele'd in nullfs_unmount.
186 */
187 nullm_rootvp = vp;
188 nullm_rootvp->v_flag |= VROOT;
189 xmp->nullm_rootvp = nullm_rootvp;
190 if (NULLVPTOLOWERVP(nullm_rootvp)->v_mount->mnt_flag & MNT_LOCAL)
191 mp->mnt_flag |= MNT_LOCAL;
192 mp->mnt_data = (qaddr_t) xmp;
193 vfs_getnewfsid(mp);
194
195 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
196 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
197 (void) copyinstr(args.target, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
198 &size);
199 bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
dadab5e9 200 (void)nullfs_statfs(mp, &mp->mnt_stat, td);
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201 NULLFSDEBUG("nullfs_mount: lower %s, alias at %s\n",
202 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
203 return (0);
204}
205
206/*
207 * VFS start. Nothing needed here - the start routine
208 * on the underlying filesystem will have been called
209 * when that filesystem was mounted.
210 */
211static int
dadab5e9 212nullfs_start(struct mount *mp, int flags, struct thread *td)
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213{
214 return (0);
dadab5e9 215 /* return VFS_START(MOUNTTONULLMOUNT(mp)->nullm_vfs, flags, td); */
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216}
217
218/*
219 * Free reference to null layer
220 */
221static int
dadab5e9 222nullfs_unmount(struct mount *mp, int mntflags, struct thread *td)
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223{
224 void *mntdata;
225 int error;
226 int flags = 0;
227
228 NULLFSDEBUG("nullfs_unmount: mp = %p\n", (void *)mp);
229
230 if (mntflags & MNT_FORCE)
231 flags |= FORCECLOSE;
232
233 /* There is 1 extra root vnode reference (nullm_rootvp). */
234 error = vflush(mp, 1, flags);
235 if (error)
236 return (error);
237
238 /*
239 * Finally, throw away the null_mount structure
240 */
241 mntdata = mp->mnt_data;
242 mp->mnt_data = 0;
243 free(mntdata, M_NULLFSMNT);
244 return 0;
245}
246
247static int
dadab5e9 248nullfs_root(struct mount *mp, struct vnode **vpp)
984263bc 249{
dadab5e9 250 struct thread *td = curthread; /* XXX */
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251 struct vnode *vp;
252
253 NULLFSDEBUG("nullfs_root(mp = %p, vp = %p->%p)\n", (void *)mp,
254 (void *)MOUNTTONULLMOUNT(mp)->nullm_rootvp,
255 (void *)NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp));
256
257 /*
258 * Return locked reference to root.
259 */
260 vp = MOUNTTONULLMOUNT(mp)->nullm_rootvp;
261 VREF(vp);
262
263#ifdef NULLFS_DEBUG
264 if (VOP_ISLOCKED(vp, NULL)) {
265 Debugger("root vnode is locked.\n");
266 vrele(vp);
267 return (EDEADLK);
268 }
269#endif
dadab5e9 270 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
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271 *vpp = vp;
272 return 0;
273}
274
275static int
dadab5e9 276nullfs_quotactl(mp, cmd, uid, arg, td)
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277 struct mount *mp;
278 int cmd;
279 uid_t uid;
280 caddr_t arg;
dadab5e9 281 struct thread *td;
984263bc 282{
dadab5e9 283 return VFS_QUOTACTL(MOUNTTONULLMOUNT(mp)->nullm_vfs, cmd, uid, arg, td);
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284}
285
286static int
dadab5e9 287nullfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td)
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288{
289 int error;
290 struct statfs mstat;
291
292 NULLFSDEBUG("nullfs_statfs(mp = %p, vp = %p->%p)\n", (void *)mp,
293 (void *)MOUNTTONULLMOUNT(mp)->nullm_rootvp,
294 (void *)NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp));
295
296 bzero(&mstat, sizeof(mstat));
297
dadab5e9 298 error = VFS_STATFS(MOUNTTONULLMOUNT(mp)->nullm_vfs, &mstat, td);
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299 if (error)
300 return (error);
301
302 /* now copy across the "interesting" information and fake the rest */
303 sbp->f_type = mstat.f_type;
304 sbp->f_flags = mstat.f_flags;
305 sbp->f_bsize = mstat.f_bsize;
306 sbp->f_iosize = mstat.f_iosize;
307 sbp->f_blocks = mstat.f_blocks;
308 sbp->f_bfree = mstat.f_bfree;
309 sbp->f_bavail = mstat.f_bavail;
310 sbp->f_files = mstat.f_files;
311 sbp->f_ffree = mstat.f_ffree;
312 if (sbp != &mp->mnt_stat) {
313 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
314 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
315 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
316 }
317 return (0);
318}
319
320static int
3b568787 321nullfs_sync(mp, waitfor, td)
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322 struct mount *mp;
323 int waitfor;
dadab5e9 324 struct thread *td;
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325{
326 /*
327 * XXX - Assumes no data cached at null layer.
328 */
329 return (0);
330}
331
332static int
333nullfs_vget(mp, ino, vpp)
334 struct mount *mp;
335 ino_t ino;
336 struct vnode **vpp;
337{
338
339 return VFS_VGET(MOUNTTONULLMOUNT(mp)->nullm_vfs, ino, vpp);
340}
341
342static int
343nullfs_fhtovp(mp, fidp, vpp)
344 struct mount *mp;
345 struct fid *fidp;
346 struct vnode **vpp;
347{
348
349 return VFS_FHTOVP(MOUNTTONULLMOUNT(mp)->nullm_vfs, fidp, vpp);
350}
351
352static int
353nullfs_checkexp(mp, nam, extflagsp, credanonp)
354 struct mount *mp;
355 struct sockaddr *nam;
356 int *extflagsp;
357 struct ucred **credanonp;
358{
359
360 return VFS_CHECKEXP(MOUNTTONULLMOUNT(mp)->nullm_vfs, nam,
361 extflagsp, credanonp);
362}
363
364static int
365nullfs_vptofh(vp, fhp)
366 struct vnode *vp;
367 struct fid *fhp;
368{
369 return VFS_VPTOFH(NULLVPTOLOWERVP(vp), fhp);
370}
371
372static int
dadab5e9 373nullfs_extattrctl(mp, cmd, attrname, arg, td)
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374 struct mount *mp;
375 int cmd;
376 const char *attrname;
377 caddr_t arg;
dadab5e9 378 struct thread *td;
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379{
380 return VFS_EXTATTRCTL(MOUNTTONULLMOUNT(mp)->nullm_vfs, cmd, attrname,
dadab5e9 381 arg, td);
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382}
383
384
385static struct vfsops null_vfsops = {
386 nullfs_mount,
387 nullfs_start,
388 nullfs_unmount,
389 nullfs_root,
390 nullfs_quotactl,
391 nullfs_statfs,
392 nullfs_sync,
393 nullfs_vget,
394 nullfs_fhtovp,
395 nullfs_checkexp,
396 nullfs_vptofh,
397 nullfs_init,
398 nullfs_uninit,
399 nullfs_extattrctl,
400};
401
402VFS_SET(null_vfsops, null, VFCF_LOOPBACK);