1 /*-
2 * Copyright (c) 1994, 1995 The Regents of the University of California.
3 * Copyright (c) 1994, 1995 Jan-Simon Pendry.
4 * Copyright (c) 2005, 2006, 2012 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
5 * Copyright (c) 2006, 2012 Daichi Goto <daichi@freebsd.org>
6 * All rights reserved.
7 *
8 * This code is derived from software donated to Berkeley by
9 * Jan-Simon Pendry.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)union_vfsops.c 8.20 (Berkeley) 5/20/95
36 * $FreeBSD$
37 */
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kdb.h>
42 #include <sys/fcntl.h>
43 #include <sys/kernel.h>
44 #include <sys/lock.h>
45 #include <sys/malloc.h>
46 #include <sys/mount.h>
47 #include <sys/namei.h>
48 #include <sys/proc.h>
49 #include <sys/vnode.h>
50 #include <sys/stat.h>
51
52 #include <fs/unionfs/union.h>
53
54 static MALLOC_DEFINE(M_UNIONFSMNT, "UNIONFS mount", "UNIONFS mount structure");
55
56 static vfs_fhtovp_t unionfs_fhtovp;
57 static vfs_checkexp_t unionfs_checkexp;
58 static vfs_mount_t unionfs_domount;
59 static vfs_quotactl_t unionfs_quotactl;
60 static vfs_root_t unionfs_root;
61 static vfs_sync_t unionfs_sync;
62 static vfs_statfs_t unionfs_statfs;
63 static vfs_unmount_t unionfs_unmount;
64 static vfs_vget_t unionfs_vget;
65 static vfs_extattrctl_t unionfs_extattrctl;
66
67 static struct vfsops unionfs_vfsops;
68
69 /*
70 * Mount unionfs layer.
71 */
72 static int
73 unionfs_domount(struct mount *mp)
74 {
75 int error;
76 struct vnode *lowerrootvp;
77 struct vnode *upperrootvp;
78 struct unionfs_mount *ump;
79 struct thread *td;
80 char *target;
81 char *tmp;
82 char *ep;
83 int len;
84 size_t done;
85 int below;
86 uid_t uid;
87 gid_t gid;
88 u_short udir;
89 u_short ufile;
90 unionfs_copymode copymode;
91 unionfs_whitemode whitemode;
92 struct componentname fakecn;
93 struct nameidata nd, *ndp;
94 struct vattr va;
95
96 UNIONFSDEBUG("unionfs_mount(mp = %p)\n", (void *)mp);
97
98 error = 0;
99 below = 0;
100 uid = 0;
101 gid = 0;
102 udir = 0;
103 ufile = 0;
104 copymode = UNIONFS_TRANSPARENT; /* default */
105 whitemode = UNIONFS_WHITE_ALWAYS;
106 ndp = &nd;
107 td = curthread;
108
109 if (mp->mnt_flag & MNT_ROOTFS) {
110 vfs_mount_error(mp, "Cannot union mount root filesystem");
111 return (EOPNOTSUPP);
112 }
113
114 /*
115 * Update is a no operation.
116 */
117 if (mp->mnt_flag & MNT_UPDATE) {
118 vfs_mount_error(mp, "unionfs does not support mount update");
119 return (EOPNOTSUPP);
120 }
121
122 /*
123 * Get argument
124 */
125 error = vfs_getopt(mp->mnt_optnew, "target", (void **)&target, &len);
126 if (error)
127 error = vfs_getopt(mp->mnt_optnew, "from", (void **)&target,
128 &len);
129 if (error || target[len - 1] != '\0') {
130 vfs_mount_error(mp, "Invalid target");
131 return (EINVAL);
132 }
133 if (vfs_getopt(mp->mnt_optnew, "below", NULL, NULL) == 0)
134 below = 1;
135 if (vfs_getopt(mp->mnt_optnew, "udir", (void **)&tmp, NULL) == 0) {
136 if (tmp != NULL)
137 udir = (mode_t)strtol(tmp, &ep, 8);
138 if (tmp == NULL || *ep) {
139 vfs_mount_error(mp, "Invalid udir");
140 return (EINVAL);
141 }
142 udir &= S_IRWXU | S_IRWXG | S_IRWXO;
143 }
144 if (vfs_getopt(mp->mnt_optnew, "ufile", (void **)&tmp, NULL) == 0) {
145 if (tmp != NULL)
146 ufile = (mode_t)strtol(tmp, &ep, 8);
147 if (tmp == NULL || *ep) {
148 vfs_mount_error(mp, "Invalid ufile");
149 return (EINVAL);
150 }
151 ufile &= S_IRWXU | S_IRWXG | S_IRWXO;
152 }
153 /* check umask, uid and gid */
154 if (udir == 0 && ufile != 0)
155 udir = ufile;
156 if (ufile == 0 && udir != 0)
157 ufile = udir;
158
159 vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY);
160 error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred);
161 if (!error) {
162 if (udir == 0)
163 udir = va.va_mode;
164 if (ufile == 0)
165 ufile = va.va_mode;
166 uid = va.va_uid;
167 gid = va.va_gid;
168 }
169 VOP_UNLOCK(mp->mnt_vnodecovered, LK_RELEASE);
170 if (error)
171 return (error);
172
173 if (mp->mnt_cred->cr_ruid == 0) { /* root only */
174 if (vfs_getopt(mp->mnt_optnew, "uid", (void **)&tmp,
175 NULL) == 0) {
176 if (tmp != NULL)
177 uid = (uid_t)strtol(tmp, &ep, 10);
178 if (tmp == NULL || *ep) {
179 vfs_mount_error(mp, "Invalid uid");
180 return (EINVAL);
181 }
182 }
183 if (vfs_getopt(mp->mnt_optnew, "gid", (void **)&tmp,
184 NULL) == 0) {
185 if (tmp != NULL)
186 gid = (gid_t)strtol(tmp, &ep, 10);
187 if (tmp == NULL || *ep) {
188 vfs_mount_error(mp, "Invalid gid");
189 return (EINVAL);
190 }
191 }
192 if (vfs_getopt(mp->mnt_optnew, "copymode", (void **)&tmp,
193 NULL) == 0) {
194 if (tmp == NULL) {
195 vfs_mount_error(mp, "Invalid copymode");
196 return (EINVAL);
197 } else if (strcasecmp(tmp, "traditional") == 0)
198 copymode = UNIONFS_TRADITIONAL;
199 else if (strcasecmp(tmp, "transparent") == 0)
200 copymode = UNIONFS_TRANSPARENT;
201 else if (strcasecmp(tmp, "masquerade") == 0)
202 copymode = UNIONFS_MASQUERADE;
203 else {
204 vfs_mount_error(mp, "Invalid copymode");
205 return (EINVAL);
206 }
207 }
208 if (vfs_getopt(mp->mnt_optnew, "whiteout", (void **)&tmp,
209 NULL) == 0) {
210 if (tmp == NULL) {
211 vfs_mount_error(mp, "Invalid whiteout mode");
212 return (EINVAL);
213 } else if (strcasecmp(tmp, "always") == 0)
214 whitemode = UNIONFS_WHITE_ALWAYS;
215 else if (strcasecmp(tmp, "whenneeded") == 0)
216 whitemode = UNIONFS_WHITE_WHENNEEDED;
217 else {
218 vfs_mount_error(mp, "Invalid whiteout mode");
219 return (EINVAL);
220 }
221 }
222 }
223 /* If copymode is UNIONFS_TRADITIONAL, uid/gid is mounted user. */
224 if (copymode == UNIONFS_TRADITIONAL) {
225 uid = mp->mnt_cred->cr_ruid;
226 gid = mp->mnt_cred->cr_rgid;
227 }
228
229 UNIONFSDEBUG("unionfs_mount: uid=%d, gid=%d\n", uid, gid);
230 UNIONFSDEBUG("unionfs_mount: udir=0%03o, ufile=0%03o\n", udir, ufile);
231 UNIONFSDEBUG("unionfs_mount: copymode=%d\n", copymode);
232
233 /*
234 * Find upper node
235 */
236 NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, target, td);
237 if ((error = namei(ndp)))
238 return (error);
239
240 NDFREE(ndp, NDF_ONLY_PNBUF);
241
242 /* get root vnodes */
243 lowerrootvp = mp->mnt_vnodecovered;
244 upperrootvp = ndp->ni_vp;
245
246 /* create unionfs_mount */
247 ump = (struct unionfs_mount *)malloc(sizeof(struct unionfs_mount),
248 M_UNIONFSMNT, M_WAITOK | M_ZERO);
249
250 /*
251 * Save reference
252 */
253 if (below) {
254 VOP_UNLOCK(upperrootvp, LK_RELEASE);
255 vn_lock(lowerrootvp, LK_EXCLUSIVE | LK_RETRY);
256 ump->um_lowervp = upperrootvp;
257 ump->um_uppervp = lowerrootvp;
258 } else {
259 ump->um_lowervp = lowerrootvp;
260 ump->um_uppervp = upperrootvp;
261 }
262 ump->um_rootvp = NULLVP;
263 ump->um_uid = uid;
264 ump->um_gid = gid;
265 ump->um_udir = udir;
266 ump->um_ufile = ufile;
267 ump->um_copymode = copymode;
268 ump->um_whitemode = whitemode;
269
270 MNT_ILOCK(mp);
271 if ((lowerrootvp->v_mount->mnt_kern_flag & MNTK_MPSAFE) &&
272 (upperrootvp->v_mount->mnt_kern_flag & MNTK_MPSAFE))
273 mp->mnt_kern_flag |= MNTK_MPSAFE;
274 MNT_IUNLOCK(mp);
275 mp->mnt_data = ump;
276
277 /*
278 * Copy upper layer's RDONLY flag.
279 */
280 mp->mnt_flag |= ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY;
281
282 /*
283 * Check whiteout
284 */
285 if ((mp->mnt_flag & MNT_RDONLY) == 0) {
286 memset(&fakecn, 0, sizeof(fakecn));
287 fakecn.cn_nameiop = LOOKUP;
288 fakecn.cn_thread = td;
289 error = VOP_WHITEOUT(ump->um_uppervp, &fakecn, LOOKUP);
290 if (error) {
291 if (below) {
292 VOP_UNLOCK(ump->um_uppervp, 0);
293 vrele(upperrootvp);
294 } else
295 vput(ump->um_uppervp);
296 free(ump, M_UNIONFSMNT);
297 mp->mnt_data = NULL;
298 return (error);
299 }
300 }
301
302 /*
303 * Unlock the node
304 */
305 VOP_UNLOCK(ump->um_uppervp, LK_RELEASE);
306
307 /*
308 * Get the unionfs root vnode.
309 */
310 error = unionfs_nodeget(mp, ump->um_uppervp, ump->um_lowervp,
311 NULLVP, &(ump->um_rootvp), NULL, td);
312 vrele(upperrootvp);
313 if (error) {
314 free(ump, M_UNIONFSMNT);
315 mp->mnt_data = NULL;
316 return (error);
317 }
318
319 /*
320 * Check mnt_flag
321 */
322 if ((ump->um_lowervp->v_mount->mnt_flag & MNT_LOCAL) &&
323 (ump->um_uppervp->v_mount->mnt_flag & MNT_LOCAL))
324 mp->mnt_flag |= MNT_LOCAL;
325
326 /*
327 * Get new fsid
328 */
329 vfs_getnewfsid(mp);
330
331 len = MNAMELEN - 1;
332 tmp = mp->mnt_stat.f_mntfromname;
333 copystr((below ? "<below>:" : "<above>:"), tmp, len, &done);
334 len -= done - 1;
335 tmp += done - 1;
336 copystr(target, tmp, len, NULL);
337
338 UNIONFSDEBUG("unionfs_mount: from %s, on %s\n",
339 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
340
341 return (0);
342 }
343
344 /*
345 * Free reference to unionfs layer
346 */
347 static int
348 unionfs_unmount(struct mount *mp, int mntflags)
349 {
350 struct unionfs_mount *ump;
351 int error;
352 int num;
353 int freeing;
354 int flags;
355
356 UNIONFSDEBUG("unionfs_unmount: mp = %p\n", (void *)mp);
357
358 ump = MOUNTTOUNIONFSMOUNT(mp);
359 flags = 0;
360
361 if (mntflags & MNT_FORCE)
362 flags |= FORCECLOSE;
363
364 /* vflush (no need to call vrele) */
365 for (freeing = 0; (error = vflush(mp, 1, flags, curthread)) != 0;) {
366 num = mp->mnt_nvnodelistsize;
367 if (num == freeing)
368 break;
369 freeing = num;
370 }
371
372 if (error)
373 return (error);
374
375 free(ump, M_UNIONFSMNT);
376 mp->mnt_data = 0;
377
378 return (0);
379 }
380
381 static int
382 unionfs_root(struct mount *mp, int flags, struct vnode **vpp)
383 {
384 struct unionfs_mount *ump;
385 struct vnode *vp;
386
387 ump = MOUNTTOUNIONFSMOUNT(mp);
388 vp = ump->um_rootvp;
389
390 UNIONFSDEBUG("unionfs_root: rootvp=%p locked=%x\n",
391 vp, VOP_ISLOCKED(vp));
392
393 vref(vp);
394 if (flags & LK_TYPE_MASK)
395 vn_lock(vp, flags);
396
397 *vpp = vp;
398
399 return (0);
400 }
401
402 static int
403 unionfs_quotactl(struct mount *mp, int cmd, uid_t uid, void *arg)
404 {
405 struct unionfs_mount *ump;
406
407 ump = MOUNTTOUNIONFSMOUNT(mp);
408
409 /*
410 * Writing is always performed to upper vnode.
411 */
412 return (VFS_QUOTACTL(ump->um_uppervp->v_mount, cmd, uid, arg));
413 }
414
415 static int
416 unionfs_statfs(struct mount *mp, struct statfs *sbp)
417 {
418 struct unionfs_mount *ump;
419 int error;
420 struct statfs mstat;
421 uint64_t lbsize;
422
423 ump = MOUNTTOUNIONFSMOUNT(mp);
424
425 UNIONFSDEBUG("unionfs_statfs(mp = %p, lvp = %p, uvp = %p)\n",
426 (void *)mp, (void *)ump->um_lowervp, (void *)ump->um_uppervp);
427
428 bzero(&mstat, sizeof(mstat));
429
430 error = VFS_STATFS(ump->um_lowervp->v_mount, &mstat);
431 if (error)
432 return (error);
433
434 /* now copy across the "interesting" information and fake the rest */
435 sbp->f_blocks = mstat.f_blocks;
436 sbp->f_files = mstat.f_files;
437
438 lbsize = mstat.f_bsize;
439
440 error = VFS_STATFS(ump->um_uppervp->v_mount, &mstat);
441 if (error)
442 return (error);
443
444 /*
445 * The FS type etc is copy from upper vfs.
446 * (write able vfs have priority)
447 */
448 sbp->f_type = mstat.f_type;
449 sbp->f_flags = mstat.f_flags;
450 sbp->f_bsize = mstat.f_bsize;
451 sbp->f_iosize = mstat.f_iosize;
452
453 if (mstat.f_bsize != lbsize)
454 sbp->f_blocks = ((off_t)sbp->f_blocks * lbsize) / mstat.f_bsize;
455
456 sbp->f_blocks += mstat.f_blocks;
457 sbp->f_bfree = mstat.f_bfree;
458 sbp->f_bavail = mstat.f_bavail;
459 sbp->f_files += mstat.f_files;
460 sbp->f_ffree = mstat.f_ffree;
461 return (0);
462 }
463
464 static int
465 unionfs_sync(struct mount *mp, int waitfor)
466 {
467 /* nothing to do */
468 return (0);
469 }
470
471 static int
472 unionfs_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
473 {
474 return (EOPNOTSUPP);
475 }
476
477 static int
478 unionfs_fhtovp(struct mount *mp, struct fid *fidp, struct vnode **vpp)
479 {
480 return (EOPNOTSUPP);
481 }
482
483 static int
484 unionfs_checkexp(struct mount *mp, struct sockaddr *nam, int *extflagsp,
485 struct ucred **credanonp, int *numsecflavors, int **secflavors)
486 {
487 return (EOPNOTSUPP);
488 }
489
490 static int
491 unionfs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp,
492 int namespace, const char *attrname)
493 {
494 struct unionfs_mount *ump;
495 struct unionfs_node *unp;
496
497 ump = MOUNTTOUNIONFSMOUNT(mp);
498 unp = VTOUNIONFS(filename_vp);
499
500 if (unp->un_uppervp != NULLVP) {
501 return (VFS_EXTATTRCTL(ump->um_uppervp->v_mount, cmd,
502 unp->un_uppervp, namespace, attrname));
503 } else {
504 return (VFS_EXTATTRCTL(ump->um_lowervp->v_mount, cmd,
505 unp->un_lowervp, namespace, attrname));
506 }
507 }
508
509 static struct vfsops unionfs_vfsops = {
510 .vfs_checkexp = unionfs_checkexp,
511 .vfs_extattrctl = unionfs_extattrctl,
512 .vfs_fhtovp = unionfs_fhtovp,
513 .vfs_init = unionfs_init,
514 .vfs_mount = unionfs_domount,
515 .vfs_quotactl = unionfs_quotactl,
516 .vfs_root = unionfs_root,
517 .vfs_statfs = unionfs_statfs,
518 .vfs_sync = unionfs_sync,
519 .vfs_uninit = unionfs_uninit,
520 .vfs_unmount = unionfs_unmount,
521 .vfs_vget = unionfs_vget,
522 };
523
524 VFS_SET(unionfs_vfsops, unionfs, VFCF_LOOPBACK);
Cache object: d4d974e0efce678cab0078bde7124a36
|