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 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc. 5 * Copyright (c) 2006 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/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/malloc.h> 45 #include <sys/mount.h> 46 #include <sys/namei.h> 47 #include <sys/proc.h> 48 #include <sys/vnode.h> 49 #include <sys/stat.h> 50 51 #include <fs/unionfs/union.h> 52 53 static MALLOC_DEFINE(M_UNIONFSMNT, "UNIONFS mount", "UNIONFS mount structure"); 54 55 static vfs_fhtovp_t unionfs_fhtovp; 56 static vfs_checkexp_t unionfs_checkexp; 57 static vfs_mount_t unionfs_domount; 58 static vfs_quotactl_t unionfs_quotactl; 59 static vfs_root_t unionfs_root; 60 static vfs_sync_t unionfs_sync; 61 static vfs_statfs_t unionfs_statfs; 62 static vfs_unmount_t unionfs_unmount; 63 static vfs_vget_t unionfs_vget; 64 static vfs_extattrctl_t unionfs_extattrctl; 65 66 static struct vfsops unionfs_vfsops; 67 68 /* 69 * Exchange from userland file mode to vmode. 70 */ 71 static u_short 72 mode2vmode(mode_t mode) 73 { 74 u_short ret; 75 76 ret = 0; 77 78 /* other */ 79 if (mode & S_IXOTH) 80 ret |= VEXEC >> 6; 81 if (mode & S_IWOTH) 82 ret |= VWRITE >> 6; 83 if (mode & S_IROTH) 84 ret |= VREAD >> 6; 85 86 /* group */ 87 if (mode & S_IXGRP) 88 ret |= VEXEC >> 3; 89 if (mode & S_IWGRP) 90 ret |= VWRITE >> 3; 91 if (mode & S_IRGRP) 92 ret |= VREAD >> 3; 93 94 /* owner */ 95 if (mode & S_IXUSR) 96 ret |= VEXEC; 97 if (mode & S_IWUSR) 98 ret |= VWRITE; 99 if (mode & S_IRUSR) 100 ret |= VREAD; 101 102 return (ret); 103 } 104 105 /* 106 * Mount unionfs layer. 107 */ 108 static int 109 unionfs_domount(struct mount *mp, struct thread *td) 110 { 111 int error; 112 struct vnode *lowerrootvp; 113 struct vnode *upperrootvp; 114 struct unionfs_mount *ump; 115 char *target; 116 char *tmp; 117 char *ep; 118 int len; 119 size_t done; 120 int below; 121 uid_t uid; 122 gid_t gid; 123 u_short udir; 124 u_short ufile; 125 unionfs_copymode copymode; 126 unionfs_whitemode whitemode; 127 struct componentname fakecn; 128 struct nameidata nd, *ndp; 129 struct vattr va; 130 131 UNIONFSDEBUG("unionfs_mount(mp = %p)\n", (void *)mp); 132 133 error = 0; 134 below = 0; 135 uid = 0; 136 gid = 0; 137 udir = 0; 138 ufile = 0; 139 copymode = UNIONFS_TRANSPARENT; /* default */ 140 whitemode = UNIONFS_WHITE_ALWAYS; 141 ndp = &nd; 142 143 if (mp->mnt_flag & MNT_ROOTFS) { 144 vfs_mount_error(mp, "Cannot union mount root filesystem"); 145 return (EOPNOTSUPP); 146 } 147 148 /* 149 * Update is a no operation. 150 */ 151 if (mp->mnt_flag & MNT_UPDATE) { 152 vfs_mount_error(mp, "unionfs does not support mount update"); 153 return (EOPNOTSUPP); 154 } 155 156 /* 157 * Get argument 158 */ 159 error = vfs_getopt(mp->mnt_optnew, "target", (void **)&target, &len); 160 if (error) 161 error = vfs_getopt(mp->mnt_optnew, "from", (void **)&target, 162 &len); 163 if (error || target[len - 1] != '\0') { 164 vfs_mount_error(mp, "Invalid target"); 165 return (EINVAL); 166 } 167 if (vfs_getopt(mp->mnt_optnew, "below", NULL, NULL) == 0) 168 below = 1; 169 if (vfs_getopt(mp->mnt_optnew, "udir", (void **)&tmp, NULL) == 0) { 170 if (tmp != NULL) 171 udir = (mode_t)strtol(tmp, &ep, 8); 172 if (tmp == NULL || *ep) { 173 vfs_mount_error(mp, "Invalid udir"); 174 return (EINVAL); 175 } 176 udir = mode2vmode(udir); 177 } 178 if (vfs_getopt(mp->mnt_optnew, "ufile", (void **)&tmp, NULL) == 0) { 179 if (tmp != NULL) 180 ufile = (mode_t)strtol(tmp, &ep, 8); 181 if (tmp == NULL || *ep) { 182 vfs_mount_error(mp, "Invalid ufile"); 183 return (EINVAL); 184 } 185 ufile = mode2vmode(ufile); 186 } 187 /* check umask, uid and gid */ 188 if (udir == 0 && ufile != 0) 189 udir = ufile; 190 if (ufile == 0 && udir != 0) 191 ufile = udir; 192 193 vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY); 194 error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred, td); 195 if (!error) { 196 if (udir == 0) 197 udir = va.va_mode; 198 if (ufile == 0) 199 ufile = va.va_mode; 200 uid = va.va_uid; 201 gid = va.va_gid; 202 } 203 VOP_UNLOCK(mp->mnt_vnodecovered, 0); 204 if (error) 205 return (error); 206 207 if (mp->mnt_cred->cr_ruid == 0) { /* root only */ 208 if (vfs_getopt(mp->mnt_optnew, "uid", (void **)&tmp, 209 NULL) == 0) { 210 if (tmp != NULL) 211 uid = (uid_t)strtol(tmp, &ep, 10); 212 if (tmp == NULL || *ep) { 213 vfs_mount_error(mp, "Invalid uid"); 214 return (EINVAL); 215 } 216 } 217 if (vfs_getopt(mp->mnt_optnew, "gid", (void **)&tmp, 218 NULL) == 0) { 219 if (tmp != NULL) 220 gid = (gid_t)strtol(tmp, &ep, 10); 221 if (tmp == NULL || *ep) { 222 vfs_mount_error(mp, "Invalid gid"); 223 return (EINVAL); 224 } 225 } 226 if (vfs_getopt(mp->mnt_optnew, "copymode", (void **)&tmp, 227 NULL) == 0) { 228 if (tmp == NULL) { 229 vfs_mount_error(mp, "Invalid copymode"); 230 return (EINVAL); 231 } else if (strcasecmp(tmp, "traditional") == 0) 232 copymode = UNIONFS_TRADITIONAL; 233 else if (strcasecmp(tmp, "transparent") == 0) 234 copymode = UNIONFS_TRANSPARENT; 235 else if (strcasecmp(tmp, "masquerade") == 0) 236 copymode = UNIONFS_MASQUERADE; 237 else { 238 vfs_mount_error(mp, "Invalid copymode"); 239 return (EINVAL); 240 } 241 } 242 if (vfs_getopt(mp->mnt_optnew, "whiteout", (void **)&tmp, 243 NULL) == 0) { 244 if (tmp == NULL) { 245 vfs_mount_error(mp, "Invalid whiteout mode"); 246 return (EINVAL); 247 } else if (strcasecmp(tmp, "always") == 0) 248 whitemode = UNIONFS_WHITE_ALWAYS; 249 else if (strcasecmp(tmp, "whenneeded") == 0) 250 whitemode = UNIONFS_WHITE_WHENNEEDED; 251 else { 252 vfs_mount_error(mp, "Invalid whiteout mode"); 253 return (EINVAL); 254 } 255 } 256 } 257 /* If copymode is UNIONFS_TRADITIONAL, uid/gid is mounted user. */ 258 if (copymode == UNIONFS_TRADITIONAL) { 259 uid = mp->mnt_cred->cr_ruid; 260 gid = mp->mnt_cred->cr_rgid; 261 } 262 263 UNIONFSDEBUG("unionfs_mount: uid=%d, gid=%d\n", uid, gid); 264 UNIONFSDEBUG("unionfs_mount: udir=0%03o, ufile=0%03o\n", udir, ufile); 265 UNIONFSDEBUG("unionfs_mount: copymode=%d\n", copymode); 266 267 /* 268 * Find upper node 269 */ 270 NDINIT(ndp, LOOKUP, FOLLOW | WANTPARENT | LOCKLEAF, UIO_SYSSPACE, target, td); 271 if ((error = namei(ndp))) 272 return (error); 273 274 NDFREE(ndp, NDF_ONLY_PNBUF); 275 276 /* get root vnodes */ 277 lowerrootvp = mp->mnt_vnodecovered; 278 upperrootvp = ndp->ni_vp; 279 280 vrele(ndp->ni_dvp); 281 ndp->ni_dvp = NULLVP; 282 283 /* create unionfs_mount */ 284 ump = (struct unionfs_mount *)malloc(sizeof(struct unionfs_mount), 285 M_UNIONFSMNT, M_WAITOK | M_ZERO); 286 287 /* 288 * Save reference 289 */ 290 if (below) { 291 VOP_UNLOCK(upperrootvp, 0); 292 vn_lock(lowerrootvp, LK_EXCLUSIVE | LK_RETRY); 293 ump->um_lowervp = upperrootvp; 294 ump->um_uppervp = lowerrootvp; 295 } else { 296 ump->um_lowervp = lowerrootvp; 297 ump->um_uppervp = upperrootvp; 298 } 299 ump->um_rootvp = NULLVP; 300 ump->um_uid = uid; 301 ump->um_gid = gid; 302 ump->um_udir = udir; 303 ump->um_ufile = ufile; 304 ump->um_copymode = copymode; 305 ump->um_whitemode = whitemode; 306 307 MNT_ILOCK(mp); 308 if ((lowerrootvp->v_mount->mnt_kern_flag & MNTK_MPSAFE) && 309 (upperrootvp->v_mount->mnt_kern_flag & MNTK_MPSAFE)) 310 mp->mnt_kern_flag |= MNTK_MPSAFE; 311 MNT_IUNLOCK(mp); 312 mp->mnt_data = ump; 313 314 /* 315 * Copy upper layer's RDONLY flag. 316 */ 317 mp->mnt_flag |= ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY; 318 319 /* 320 * Check whiteout 321 */ 322 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 323 memset(&fakecn, 0, sizeof(fakecn)); 324 fakecn.cn_nameiop = LOOKUP; 325 fakecn.cn_thread = td; 326 error = VOP_WHITEOUT(ump->um_uppervp, &fakecn, LOOKUP); 327 if (error) { 328 if (below) { 329 VOP_UNLOCK(ump->um_uppervp, 0); 330 vrele(upperrootvp); 331 } else 332 vput(ump->um_uppervp); 333 free(ump, M_UNIONFSMNT); 334 mp->mnt_data = NULL; 335 return (error); 336 } 337 } 338 339 /* 340 * Unlock the node 341 */ 342 VOP_UNLOCK(ump->um_uppervp, 0); 343 344 /* 345 * Get the unionfs root vnode. 346 */ 347 error = unionfs_nodeget(mp, ump->um_uppervp, ump->um_lowervp, 348 NULLVP, &(ump->um_rootvp), NULL, td); 349 vrele(upperrootvp); 350 if (error) { 351 free(ump, M_UNIONFSMNT); 352 mp->mnt_data = NULL; 353 return (error); 354 } 355 356 /* 357 * Check mnt_flag 358 */ 359 if ((ump->um_lowervp->v_mount->mnt_flag & MNT_LOCAL) && 360 (ump->um_uppervp->v_mount->mnt_flag & MNT_LOCAL)) 361 mp->mnt_flag |= MNT_LOCAL; 362 363 /* 364 * Get new fsid 365 */ 366 vfs_getnewfsid(mp); 367 368 len = MNAMELEN - 1; 369 tmp = mp->mnt_stat.f_mntfromname; 370 copystr((below ? "<below>:" : "<above>:"), tmp, len, &done); 371 len -= done - 1; 372 tmp += done - 1; 373 copystr(target, tmp, len, NULL); 374 375 UNIONFSDEBUG("unionfs_mount: from %s, on %s\n", 376 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 377 378 return (0); 379 } 380 381 /* 382 * Free reference to unionfs layer 383 */ 384 static int 385 unionfs_unmount(struct mount *mp, int mntflags, struct thread *td) 386 { 387 struct unionfs_mount *ump; 388 int error; 389 int num; 390 int freeing; 391 int flags; 392 393 UNIONFSDEBUG("unionfs_unmount: mp = %p\n", (void *)mp); 394 395 ump = MOUNTTOUNIONFSMOUNT(mp); 396 flags = 0; 397 398 if (mntflags & MNT_FORCE) 399 flags |= FORCECLOSE; 400 401 /* vflush (no need to call vrele) */ 402 for (freeing = 0; (error = vflush(mp, 1, flags, td)) != 0;) { 403 num = mp->mnt_nvnodelistsize; 404 if (num == freeing) 405 break; 406 freeing = num; 407 } 408 409 if (error) 410 return (error); 411 412 free(ump, M_UNIONFSMNT); 413 mp->mnt_data = 0; 414 415 return (0); 416 } 417 418 static int 419 unionfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) 420 { 421 struct unionfs_mount *ump; 422 struct vnode *vp; 423 424 ump = MOUNTTOUNIONFSMOUNT(mp); 425 vp = ump->um_rootvp; 426 427 UNIONFSDEBUG("unionfs_root: rootvp=%p locked=%x\n", 428 vp, VOP_ISLOCKED(vp, td)); 429 430 vref(vp); 431 if (flags & LK_TYPE_MASK) 432 vn_lock(vp, flags); 433 434 *vpp = vp; 435 436 return (0); 437 } 438 439 static int 440 unionfs_quotactl(struct mount *mp, int cmd, uid_t uid, void *arg, 441 struct thread *td) 442 { 443 struct unionfs_mount *ump; 444 445 ump = MOUNTTOUNIONFSMOUNT(mp); 446 447 /* 448 * Writing is always performed to upper vnode. 449 */ 450 return (VFS_QUOTACTL(ump->um_uppervp->v_mount, cmd, uid, arg, td)); 451 } 452 453 static int 454 unionfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 455 { 456 struct unionfs_mount *ump; 457 int error; 458 struct statfs mstat; 459 uint64_t lbsize; 460 461 ump = MOUNTTOUNIONFSMOUNT(mp); 462 463 UNIONFSDEBUG("unionfs_statfs(mp = %p, lvp = %p, uvp = %p)\n", 464 (void *)mp, (void *)ump->um_lowervp, (void *)ump->um_uppervp); 465 466 bzero(&mstat, sizeof(mstat)); 467 468 error = VFS_STATFS(ump->um_lowervp->v_mount, &mstat, td); 469 if (error) 470 return (error); 471 472 /* now copy across the "interesting" information and fake the rest */ 473 sbp->f_blocks = mstat.f_blocks; 474 sbp->f_files = mstat.f_files; 475 476 lbsize = mstat.f_bsize; 477 478 error = VFS_STATFS(ump->um_uppervp->v_mount, &mstat, td); 479 if (error) 480 return (error); 481 482 /* 483 * The FS type etc is copy from upper vfs. 484 * (write able vfs have priority) 485 */ 486 sbp->f_type = mstat.f_type; 487 sbp->f_flags = mstat.f_flags; 488 sbp->f_bsize = mstat.f_bsize; 489 sbp->f_iosize = mstat.f_iosize; 490 491 if (mstat.f_bsize != lbsize) 492 sbp->f_blocks = ((off_t)sbp->f_blocks * lbsize) / mstat.f_bsize; 493 494 sbp->f_blocks += mstat.f_blocks; 495 sbp->f_bfree = mstat.f_bfree; 496 sbp->f_bavail = mstat.f_bavail; 497 sbp->f_files += mstat.f_files; 498 sbp->f_ffree = mstat.f_ffree; 499 return (0); 500 } 501 502 static int 503 unionfs_sync(struct mount *mp, int waitfor, struct thread *td) 504 { 505 /* nothing to do */ 506 return (0); 507 } 508 509 static int 510 unionfs_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp) 511 { 512 return (EOPNOTSUPP); 513 } 514 515 static int 516 unionfs_fhtovp(struct mount *mp, struct fid *fidp, struct vnode **vpp) 517 { 518 return (EOPNOTSUPP); 519 } 520 521 static int 522 unionfs_checkexp(struct mount *mp, struct sockaddr *nam, int *extflagsp, 523 struct ucred **credanonp) 524 { 525 return (EOPNOTSUPP); 526 } 527 528 static int 529 unionfs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp, 530 int namespace, const char *attrname, struct thread *td) 531 { 532 struct unionfs_mount *ump; 533 struct unionfs_node *unp; 534 535 ump = MOUNTTOUNIONFSMOUNT(mp); 536 unp = VTOUNIONFS(filename_vp); 537 538 if (unp->un_uppervp != NULLVP) { 539 return (VFS_EXTATTRCTL(ump->um_uppervp->v_mount, cmd, 540 unp->un_uppervp, namespace, attrname, td)); 541 } else { 542 return (VFS_EXTATTRCTL(ump->um_lowervp->v_mount, cmd, 543 unp->un_lowervp, namespace, attrname, td)); 544 } 545 } 546 547 static struct vfsops unionfs_vfsops = { 548 .vfs_checkexp = unionfs_checkexp, 549 .vfs_extattrctl = unionfs_extattrctl, 550 .vfs_fhtovp = unionfs_fhtovp, 551 .vfs_init = unionfs_init, 552 .vfs_mount = unionfs_domount, 553 .vfs_quotactl = unionfs_quotactl, 554 .vfs_root = unionfs_root, 555 .vfs_statfs = unionfs_statfs, 556 .vfs_sync = unionfs_sync, 557 .vfs_uninit = unionfs_uninit, 558 .vfs_unmount = unionfs_unmount, 559 .vfs_vget = unionfs_vget, 560 }; 561 562 VFS_SET(unionfs_vfsops, unionfs, VFCF_LOOPBACK); 563