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 nameidata nd, *ndp; 93 struct vattr va; 94 95 UNIONFSDEBUG("unionfs_mount(mp = %p)\n", (void *)mp); 96 97 error = 0; 98 below = 0; 99 uid = 0; 100 gid = 0; 101 udir = 0; 102 ufile = 0; 103 copymode = UNIONFS_TRANSPARENT; /* default */ 104 whitemode = UNIONFS_WHITE_ALWAYS; 105 ndp = &nd; 106 td = curthread; 107 108 if (mp->mnt_flag & MNT_ROOTFS) { 109 vfs_mount_error(mp, "Cannot union mount root filesystem"); 110 return (EOPNOTSUPP); 111 } 112 113 /* 114 * Update is a no operation. 115 */ 116 if (mp->mnt_flag & MNT_UPDATE) { 117 vfs_mount_error(mp, "unionfs does not support mount update"); 118 return (EOPNOTSUPP); 119 } 120 121 /* 122 * Get argument 123 */ 124 error = vfs_getopt(mp->mnt_optnew, "target", (void **)&target, &len); 125 if (error) 126 error = vfs_getopt(mp->mnt_optnew, "from", (void **)&target, 127 &len); 128 if (error || target[len - 1] != '\0') { 129 vfs_mount_error(mp, "Invalid target"); 130 return (EINVAL); 131 } 132 if (vfs_getopt(mp->mnt_optnew, "below", NULL, NULL) == 0) 133 below = 1; 134 if (vfs_getopt(mp->mnt_optnew, "udir", (void **)&tmp, NULL) == 0) { 135 if (tmp != NULL) 136 udir = (mode_t)strtol(tmp, &ep, 8); 137 if (tmp == NULL || *ep) { 138 vfs_mount_error(mp, "Invalid udir"); 139 return (EINVAL); 140 } 141 udir &= S_IRWXU | S_IRWXG | S_IRWXO; 142 } 143 if (vfs_getopt(mp->mnt_optnew, "ufile", (void **)&tmp, NULL) == 0) { 144 if (tmp != NULL) 145 ufile = (mode_t)strtol(tmp, &ep, 8); 146 if (tmp == NULL || *ep) { 147 vfs_mount_error(mp, "Invalid ufile"); 148 return (EINVAL); 149 } 150 ufile &= S_IRWXU | S_IRWXG | S_IRWXO; 151 } 152 /* check umask, uid and gid */ 153 if (udir == 0 && ufile != 0) 154 udir = ufile; 155 if (ufile == 0 && udir != 0) 156 ufile = udir; 157 158 vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY); 159 error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred); 160 if (!error) { 161 if (udir == 0) 162 udir = va.va_mode; 163 if (ufile == 0) 164 ufile = va.va_mode; 165 uid = va.va_uid; 166 gid = va.va_gid; 167 } 168 VOP_UNLOCK(mp->mnt_vnodecovered, LK_RELEASE); 169 if (error) 170 return (error); 171 172 if (mp->mnt_cred->cr_ruid == 0) { /* root only */ 173 if (vfs_getopt(mp->mnt_optnew, "uid", (void **)&tmp, 174 NULL) == 0) { 175 if (tmp != NULL) 176 uid = (uid_t)strtol(tmp, &ep, 10); 177 if (tmp == NULL || *ep) { 178 vfs_mount_error(mp, "Invalid uid"); 179 return (EINVAL); 180 } 181 } 182 if (vfs_getopt(mp->mnt_optnew, "gid", (void **)&tmp, 183 NULL) == 0) { 184 if (tmp != NULL) 185 gid = (gid_t)strtol(tmp, &ep, 10); 186 if (tmp == NULL || *ep) { 187 vfs_mount_error(mp, "Invalid gid"); 188 return (EINVAL); 189 } 190 } 191 if (vfs_getopt(mp->mnt_optnew, "copymode", (void **)&tmp, 192 NULL) == 0) { 193 if (tmp == NULL) { 194 vfs_mount_error(mp, "Invalid copymode"); 195 return (EINVAL); 196 } else if (strcasecmp(tmp, "traditional") == 0) 197 copymode = UNIONFS_TRADITIONAL; 198 else if (strcasecmp(tmp, "transparent") == 0) 199 copymode = UNIONFS_TRANSPARENT; 200 else if (strcasecmp(tmp, "masquerade") == 0) 201 copymode = UNIONFS_MASQUERADE; 202 else { 203 vfs_mount_error(mp, "Invalid copymode"); 204 return (EINVAL); 205 } 206 } 207 if (vfs_getopt(mp->mnt_optnew, "whiteout", (void **)&tmp, 208 NULL) == 0) { 209 if (tmp == NULL) { 210 vfs_mount_error(mp, "Invalid whiteout mode"); 211 return (EINVAL); 212 } else if (strcasecmp(tmp, "always") == 0) 213 whitemode = UNIONFS_WHITE_ALWAYS; 214 else if (strcasecmp(tmp, "whenneeded") == 0) 215 whitemode = UNIONFS_WHITE_WHENNEEDED; 216 else { 217 vfs_mount_error(mp, "Invalid whiteout mode"); 218 return (EINVAL); 219 } 220 } 221 } 222 /* If copymode is UNIONFS_TRADITIONAL, uid/gid is mounted user. */ 223 if (copymode == UNIONFS_TRADITIONAL) { 224 uid = mp->mnt_cred->cr_ruid; 225 gid = mp->mnt_cred->cr_rgid; 226 } 227 228 UNIONFSDEBUG("unionfs_mount: uid=%d, gid=%d\n", uid, gid); 229 UNIONFSDEBUG("unionfs_mount: udir=0%03o, ufile=0%03o\n", udir, ufile); 230 UNIONFSDEBUG("unionfs_mount: copymode=%d\n", copymode); 231 232 /* 233 * Find upper node 234 */ 235 NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, target, td); 236 if ((error = namei(ndp))) 237 return (error); 238 239 NDFREE(ndp, NDF_ONLY_PNBUF); 240 241 /* get root vnodes */ 242 lowerrootvp = mp->mnt_vnodecovered; 243 upperrootvp = ndp->ni_vp; 244 245 /* create unionfs_mount */ 246 ump = (struct unionfs_mount *)malloc(sizeof(struct unionfs_mount), 247 M_UNIONFSMNT, M_WAITOK | M_ZERO); 248 249 /* 250 * Save reference 251 */ 252 if (below) { 253 VOP_UNLOCK(upperrootvp, LK_RELEASE); 254 vn_lock(lowerrootvp, LK_EXCLUSIVE | LK_RETRY); 255 ump->um_lowervp = upperrootvp; 256 ump->um_uppervp = lowerrootvp; 257 } else { 258 ump->um_lowervp = lowerrootvp; 259 ump->um_uppervp = upperrootvp; 260 } 261 ump->um_rootvp = NULLVP; 262 ump->um_uid = uid; 263 ump->um_gid = gid; 264 ump->um_udir = udir; 265 ump->um_ufile = ufile; 266 ump->um_copymode = copymode; 267 ump->um_whitemode = whitemode; 268 269 mp->mnt_data = ump; 270 271 /* 272 * Copy upper layer's RDONLY flag. 273 */ 274 mp->mnt_flag |= ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY; 275 276 /* 277 * Unlock the node 278 */ 279 VOP_UNLOCK(ump->um_uppervp, LK_RELEASE); 280 281 /* 282 * Get the unionfs root vnode. 283 */ 284 error = unionfs_nodeget(mp, ump->um_uppervp, ump->um_lowervp, 285 NULLVP, &(ump->um_rootvp), NULL, td); 286 vrele(upperrootvp); 287 if (error) { 288 free(ump, M_UNIONFSMNT); 289 mp->mnt_data = NULL; 290 return (error); 291 } 292 293 MNT_ILOCK(mp); 294 if ((ump->um_lowervp->v_mount->mnt_flag & MNT_LOCAL) && 295 (ump->um_uppervp->v_mount->mnt_flag & MNT_LOCAL)) 296 mp->mnt_flag |= MNT_LOCAL; 297 MNT_IUNLOCK(mp); 298 299 /* 300 * Get new fsid 301 */ 302 vfs_getnewfsid(mp); 303 304 len = MNAMELEN - 1; 305 tmp = mp->mnt_stat.f_mntfromname; 306 copystr((below ? "<below>:" : "<above>:"), tmp, len, &done); 307 len -= done - 1; 308 tmp += done - 1; 309 copystr(target, tmp, len, NULL); 310 311 UNIONFSDEBUG("unionfs_mount: from %s, on %s\n", 312 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 313 314 return (0); 315 } 316 317 /* 318 * Free reference to unionfs layer 319 */ 320 static int 321 unionfs_unmount(struct mount *mp, int mntflags) 322 { 323 struct unionfs_mount *ump; 324 int error; 325 int num; 326 int freeing; 327 int flags; 328 329 UNIONFSDEBUG("unionfs_unmount: mp = %p\n", (void *)mp); 330 331 ump = MOUNTTOUNIONFSMOUNT(mp); 332 flags = 0; 333 334 if (mntflags & MNT_FORCE) 335 flags |= FORCECLOSE; 336 337 /* vflush (no need to call vrele) */ 338 for (freeing = 0; (error = vflush(mp, 1, flags, curthread)) != 0;) { 339 num = mp->mnt_nvnodelistsize; 340 if (num == freeing) 341 break; 342 freeing = num; 343 } 344 345 if (error) 346 return (error); 347 348 free(ump, M_UNIONFSMNT); 349 mp->mnt_data = NULL; 350 351 return (0); 352 } 353 354 static int 355 unionfs_root(struct mount *mp, int flags, struct vnode **vpp) 356 { 357 struct unionfs_mount *ump; 358 struct vnode *vp; 359 360 ump = MOUNTTOUNIONFSMOUNT(mp); 361 vp = ump->um_rootvp; 362 363 UNIONFSDEBUG("unionfs_root: rootvp=%p locked=%x\n", 364 vp, VOP_ISLOCKED(vp)); 365 366 vref(vp); 367 if (flags & LK_TYPE_MASK) 368 vn_lock(vp, flags); 369 370 *vpp = vp; 371 372 return (0); 373 } 374 375 static int 376 unionfs_quotactl(struct mount *mp, int cmd, uid_t uid, void *arg) 377 { 378 struct unionfs_mount *ump; 379 380 ump = MOUNTTOUNIONFSMOUNT(mp); 381 382 /* 383 * Writing is always performed to upper vnode. 384 */ 385 return (VFS_QUOTACTL(ump->um_uppervp->v_mount, cmd, uid, arg)); 386 } 387 388 static int 389 unionfs_statfs(struct mount *mp, struct statfs *sbp) 390 { 391 struct unionfs_mount *ump; 392 int error; 393 struct statfs mstat; 394 uint64_t lbsize; 395 396 ump = MOUNTTOUNIONFSMOUNT(mp); 397 398 UNIONFSDEBUG("unionfs_statfs(mp = %p, lvp = %p, uvp = %p)\n", 399 (void *)mp, (void *)ump->um_lowervp, (void *)ump->um_uppervp); 400 401 bzero(&mstat, sizeof(mstat)); 402 403 error = VFS_STATFS(ump->um_lowervp->v_mount, &mstat); 404 if (error) 405 return (error); 406 407 /* now copy across the "interesting" information and fake the rest */ 408 sbp->f_blocks = mstat.f_blocks; 409 sbp->f_files = mstat.f_files; 410 411 lbsize = mstat.f_bsize; 412 413 error = VFS_STATFS(ump->um_uppervp->v_mount, &mstat); 414 if (error) 415 return (error); 416 417 /* 418 * The FS type etc is copy from upper vfs. 419 * (write able vfs have priority) 420 */ 421 sbp->f_type = mstat.f_type; 422 sbp->f_flags = mstat.f_flags; 423 sbp->f_bsize = mstat.f_bsize; 424 sbp->f_iosize = mstat.f_iosize; 425 426 if (mstat.f_bsize != lbsize) 427 sbp->f_blocks = ((off_t)sbp->f_blocks * lbsize) / mstat.f_bsize; 428 429 sbp->f_blocks += mstat.f_blocks; 430 sbp->f_bfree = mstat.f_bfree; 431 sbp->f_bavail = mstat.f_bavail; 432 sbp->f_files += mstat.f_files; 433 sbp->f_ffree = mstat.f_ffree; 434 return (0); 435 } 436 437 static int 438 unionfs_sync(struct mount *mp, int waitfor) 439 { 440 /* nothing to do */ 441 return (0); 442 } 443 444 static int 445 unionfs_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp) 446 { 447 return (EOPNOTSUPP); 448 } 449 450 static int 451 unionfs_fhtovp(struct mount *mp, struct fid *fidp, int flags, 452 struct vnode **vpp) 453 { 454 return (EOPNOTSUPP); 455 } 456 457 static int 458 unionfs_checkexp(struct mount *mp, struct sockaddr *nam, int *extflagsp, 459 struct ucred **credanonp, int *numsecflavors, int **secflavors) 460 { 461 return (EOPNOTSUPP); 462 } 463 464 static int 465 unionfs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp, 466 int namespace, const char *attrname) 467 { 468 struct unionfs_mount *ump; 469 struct unionfs_node *unp; 470 471 ump = MOUNTTOUNIONFSMOUNT(mp); 472 unp = VTOUNIONFS(filename_vp); 473 474 if (unp->un_uppervp != NULLVP) { 475 return (VFS_EXTATTRCTL(ump->um_uppervp->v_mount, cmd, 476 unp->un_uppervp, namespace, attrname)); 477 } else { 478 return (VFS_EXTATTRCTL(ump->um_lowervp->v_mount, cmd, 479 unp->un_lowervp, namespace, attrname)); 480 } 481 } 482 483 static struct vfsops unionfs_vfsops = { 484 .vfs_checkexp = unionfs_checkexp, 485 .vfs_extattrctl = unionfs_extattrctl, 486 .vfs_fhtovp = unionfs_fhtovp, 487 .vfs_init = unionfs_init, 488 .vfs_mount = unionfs_domount, 489 .vfs_quotactl = unionfs_quotactl, 490 .vfs_root = unionfs_root, 491 .vfs_statfs = unionfs_statfs, 492 .vfs_sync = unionfs_sync, 493 .vfs_uninit = unionfs_uninit, 494 .vfs_unmount = unionfs_unmount, 495 .vfs_vget = unionfs_vget, 496 }; 497 498 VFS_SET(unionfs_vfsops, unionfs, VFCF_LOOPBACK); 499