1 /*- 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1999 Michael Smith 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 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 AUTHOR 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 AUTHOR 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 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/conf.h> 42 #include <sys/jail.h> 43 #include <sys/kernel.h> 44 #include <sys/libkern.h> 45 #include <sys/mac.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/namei.h> 50 #include <sys/proc.h> 51 #include <sys/filedesc.h> 52 #include <sys/reboot.h> 53 #include <sys/syscallsubr.h> 54 #include <sys/sysproto.h> 55 #include <sys/sx.h> 56 #include <sys/sysctl.h> 57 #include <sys/sysent.h> 58 #include <sys/systm.h> 59 #include <sys/vnode.h> 60 61 #include <geom/geom.h> 62 63 #include <machine/stdarg.h> 64 65 #include "opt_rootdevname.h" 66 #include "opt_ddb.h" 67 #include "opt_mac.h" 68 69 #ifdef DDB 70 #include <ddb/ddb.h> 71 #endif 72 73 #define ROOTNAME "root_device" 74 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 75 76 static int vfs_domount(struct thread *td, const char *fstype, 77 char *fspath, int fsflags, void *fsdata); 78 static int vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 79 const char *fspath, struct thread *td, struct mount **mpp); 80 static int vfs_mountroot_ask(void); 81 static int vfs_mountroot_try(const char *mountfrom); 82 static int vfs_donmount(struct thread *td, int fsflags, 83 struct uio *fsoptions); 84 85 static int usermount = 0; 86 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 87 "Unprivileged users may mount and unmount file systems"); 88 89 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 90 91 /* List of mounted filesystems. */ 92 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 93 94 /* For any iteration/modification of mountlist */ 95 struct mtx mountlist_mtx; 96 97 TAILQ_HEAD(vfsoptlist, vfsopt); 98 struct vfsopt { 99 TAILQ_ENTRY(vfsopt) link; 100 char *name; 101 void *value; 102 int len; 103 }; 104 105 /* 106 * The vnode of the system's root (/ in the filesystem, without chroot 107 * active.) 108 */ 109 struct vnode *rootvnode; 110 111 /* 112 * The root filesystem is detailed in the kernel environment variable 113 * vfs.root.mountfrom, which is expected to be in the general format 114 * 115 * <vfsname>:[<path>] 116 * vfsname := the name of a VFS known to the kernel and capable 117 * of being mounted as root 118 * path := disk device name or other data used by the filesystem 119 * to locate its physical store 120 */ 121 122 /* 123 * Global opts, taken by all filesystems 124 */ 125 static const char *global_opts[] = { 126 "fstype", 127 "fspath", 128 "ro", 129 "suid", 130 "exec", 131 NULL 132 }; 133 134 /* 135 * The root specifiers we will try if RB_CDROM is specified. 136 */ 137 static char *cdrom_rootdevnames[] = { 138 "cd9660:cd0", 139 "cd9660:acd0", 140 NULL 141 }; 142 143 /* legacy find-root code */ 144 char *rootdevnames[2] = {NULL, NULL}; 145 #ifndef ROOTDEVNAME 146 # define ROOTDEVNAME NULL 147 #endif 148 const char *ctrootdevname = ROOTDEVNAME; 149 150 /* 151 * --------------------------------------------------------------------- 152 * Functions for building and sanitizing the mount options 153 */ 154 155 /* Remove one mount option. */ 156 static void 157 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 158 { 159 160 TAILQ_REMOVE(opts, opt, link); 161 free(opt->name, M_MOUNT); 162 if (opt->value != NULL) 163 free(opt->value, M_MOUNT); 164 #ifdef INVARIANTS 165 else if (opt->len != 0) 166 panic("%s: mount option with NULL value but length != 0", 167 __func__); 168 #endif 169 free(opt, M_MOUNT); 170 } 171 172 /* Release all resources related to the mount options. */ 173 static void 174 vfs_freeopts(struct vfsoptlist *opts) 175 { 176 struct vfsopt *opt; 177 178 while (!TAILQ_EMPTY(opts)) { 179 opt = TAILQ_FIRST(opts); 180 vfs_freeopt(opts, opt); 181 } 182 free(opts, M_MOUNT); 183 } 184 185 /* 186 * Check if options are equal (with or without the "no" prefix). 187 */ 188 static int 189 vfs_equalopts(const char *opt1, const char *opt2) 190 { 191 192 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 193 if (strcmp(opt1, opt2) == 0) 194 return (1); 195 /* "noopt" vs. "opt" */ 196 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 197 return (1); 198 /* "opt" vs. "noopt" */ 199 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 200 return (1); 201 return (0); 202 } 203 204 /* 205 * If a mount option is specified several times, 206 * (with or without the "no" prefix) only keep 207 * the last occurence of it. 208 */ 209 static void 210 vfs_sanitizeopts(struct vfsoptlist *opts) 211 { 212 struct vfsopt *opt, *opt2, *tmp; 213 214 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 215 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 216 while (opt2 != NULL) { 217 if (vfs_equalopts(opt->name, opt2->name)) { 218 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 219 vfs_freeopt(opts, opt2); 220 opt2 = tmp; 221 } else { 222 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 223 } 224 } 225 } 226 } 227 228 /* 229 * Build a linked list of mount options from a struct uio. 230 */ 231 static int 232 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 233 { 234 struct vfsoptlist *opts; 235 struct vfsopt *opt; 236 size_t memused; 237 unsigned int i, iovcnt; 238 int error, namelen, optlen; 239 240 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 241 TAILQ_INIT(opts); 242 memused = 0; 243 iovcnt = auio->uio_iovcnt; 244 for (i = 0; i < iovcnt; i += 2) { 245 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 246 namelen = auio->uio_iov[i].iov_len; 247 optlen = auio->uio_iov[i + 1].iov_len; 248 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 249 opt->value = NULL; 250 opt->len = 0; 251 252 /* 253 * Do this early, so jumps to "bad" will free the current 254 * option. 255 */ 256 TAILQ_INSERT_TAIL(opts, opt, link); 257 memused += sizeof(struct vfsopt) + optlen + namelen; 258 259 /* 260 * Avoid consuming too much memory, and attempts to overflow 261 * memused. 262 */ 263 if (memused > VFS_MOUNTARG_SIZE_MAX || 264 optlen > VFS_MOUNTARG_SIZE_MAX || 265 namelen > VFS_MOUNTARG_SIZE_MAX) { 266 error = EINVAL; 267 goto bad; 268 } 269 270 if (auio->uio_segflg == UIO_SYSSPACE) { 271 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 272 } else { 273 error = copyin(auio->uio_iov[i].iov_base, opt->name, 274 namelen); 275 if (error) 276 goto bad; 277 } 278 /* Ensure names are null-terminated strings. */ 279 if (opt->name[namelen - 1] != '\0') { 280 error = EINVAL; 281 goto bad; 282 } 283 if (optlen != 0) { 284 opt->len = optlen; 285 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 286 if (auio->uio_segflg == UIO_SYSSPACE) { 287 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 288 optlen); 289 } else { 290 error = copyin(auio->uio_iov[i + 1].iov_base, 291 opt->value, optlen); 292 if (error) 293 goto bad; 294 } 295 } 296 } 297 vfs_sanitizeopts(opts); 298 *options = opts; 299 return (0); 300 bad: 301 vfs_freeopts(opts); 302 return (error); 303 } 304 305 /* 306 * Merge the old mount options with the new ones passed 307 * in the MNT_UPDATE case. 308 */ 309 static void 310 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 311 { 312 struct vfsopt *opt, *opt2, *new; 313 314 TAILQ_FOREACH(opt, opts, link) { 315 /* 316 * Check that this option hasn't been redefined 317 * nor cancelled with a "no" mount option. 318 */ 319 opt2 = TAILQ_FIRST(toopts); 320 while (opt2 != NULL) { 321 if (strcmp(opt2->name, opt->name) == 0) 322 goto next; 323 if (strncmp(opt2->name, "no", 2) == 0 && 324 strcmp(opt2->name + 2, opt->name) == 0) { 325 vfs_freeopt(toopts, opt2); 326 goto next; 327 } 328 opt2 = TAILQ_NEXT(opt2, link); 329 } 330 /* We want this option, duplicate it. */ 331 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 332 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 333 strcpy(new->name, opt->name); 334 if (opt->len != 0) { 335 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 336 bcopy(opt->value, new->value, opt->len); 337 } else { 338 new->value = NULL; 339 } 340 new->len = opt->len; 341 TAILQ_INSERT_TAIL(toopts, new, link); 342 next: 343 continue; 344 } 345 } 346 347 /* 348 * --------------------------------------------------------------------- 349 * Mount a filesystem 350 */ 351 int 352 nmount(td, uap) 353 struct thread *td; 354 struct nmount_args /* { 355 struct iovec *iovp; 356 unsigned int iovcnt; 357 int flags; 358 } */ *uap; 359 { 360 struct uio *auio; 361 struct iovec *iov; 362 unsigned int i; 363 int error; 364 u_int iovcnt; 365 366 /* Kick out MNT_ROOTFS early as it is legal internally */ 367 if (uap->flags & MNT_ROOTFS) 368 return (EINVAL); 369 370 iovcnt = uap->iovcnt; 371 /* 372 * Check that we have an even number of iovec's 373 * and that we have at least two options. 374 */ 375 if ((iovcnt & 1) || (iovcnt < 4)) 376 return (EINVAL); 377 378 error = copyinuio(uap->iovp, iovcnt, &auio); 379 if (error) 380 return (error); 381 iov = auio->uio_iov; 382 for (i = 0; i < iovcnt; i++) { 383 if (iov->iov_len > MMAXOPTIONLEN) { 384 free(auio, M_IOV); 385 return (EINVAL); 386 } 387 iov++; 388 } 389 error = vfs_donmount(td, uap->flags, auio); 390 free(auio, M_IOV); 391 return (error); 392 } 393 394 /* 395 * --------------------------------------------------------------------- 396 * Various utility functions 397 */ 398 399 /* 400 * Allocate and initialize the mount point struct. 401 */ 402 static int 403 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 404 const char *fspath, struct thread *td, struct mount **mpp) 405 { 406 struct mount *mp; 407 408 mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 409 TAILQ_INIT(&mp->mnt_nvnodelist); 410 mp->mnt_nvnodelistsize = 0; 411 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 412 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 413 vfs_busy(mp, LK_NOWAIT, 0, td); 414 mp->mnt_op = vfsp->vfc_vfsops; 415 mp->mnt_vfc = vfsp; 416 vfsp->vfc_refcount++; 417 mp->mnt_stat.f_type = vfsp->vfc_typenum; 418 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 419 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 420 mp->mnt_vnodecovered = vp; 421 mp->mnt_cred = crdup(td->td_ucred); 422 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 423 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 424 mp->mnt_iosize_max = DFLTPHYS; 425 #ifdef MAC 426 mac_init_mount(mp); 427 mac_create_mount(td->td_ucred, mp); 428 #endif 429 *mpp = mp; 430 return (0); 431 } 432 433 /* 434 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 435 */ 436 void 437 vfs_mount_destroy(struct mount *mp, struct thread *td) 438 { 439 440 mp->mnt_vfc->vfc_refcount--; 441 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 442 panic("unmount: dangling vnode"); 443 vfs_unbusy(mp,td); 444 lockdestroy(&mp->mnt_lock); 445 MNT_ILOCK(mp); 446 if (mp->mnt_kern_flag & MNTK_MWAIT) 447 wakeup(mp); 448 MNT_IUNLOCK(mp); 449 mtx_destroy(&mp->mnt_mtx); 450 #ifdef MAC 451 mac_destroy_mount(mp); 452 #endif 453 if (mp->mnt_opt != NULL) 454 vfs_freeopts(mp->mnt_opt); 455 crfree(mp->mnt_cred); 456 free(mp, M_MOUNT); 457 } 458 459 static int 460 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 461 { 462 struct vfsoptlist *optlist; 463 char *fstype, *fspath; 464 int error, fstypelen, fspathlen; 465 466 error = vfs_buildopts(fsoptions, &optlist); 467 if (error) 468 return (error); 469 470 /* 471 * We need these two options before the others, 472 * and they are mandatory for any filesystem. 473 * Ensure they are NUL terminated as well. 474 */ 475 fstypelen = 0; 476 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 477 if (error || fstype[fstypelen - 1] != '\0') { 478 error = EINVAL; 479 goto bail; 480 } 481 fspathlen = 0; 482 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 483 if (error || fspath[fspathlen - 1] != '\0') { 484 error = EINVAL; 485 goto bail; 486 } 487 488 /* 489 * Be ultra-paranoid about making sure the type and fspath 490 * variables will fit in our mp buffers, including the 491 * terminating NUL. 492 */ 493 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 494 error = ENAMETOOLONG; 495 goto bail; 496 } 497 498 mtx_lock(&Giant); 499 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 500 mtx_unlock(&Giant); 501 bail: 502 if (error) 503 vfs_freeopts(optlist); 504 return (error); 505 } 506 507 /* 508 * --------------------------------------------------------------------- 509 * Old mount API. 510 */ 511 #ifndef _SYS_SYSPROTO_H_ 512 struct mount_args { 513 char *type; 514 char *path; 515 int flags; 516 caddr_t data; 517 }; 518 #endif 519 /* ARGSUSED */ 520 int 521 mount(td, uap) 522 struct thread *td; 523 struct mount_args /* { 524 char *type; 525 char *path; 526 int flags; 527 caddr_t data; 528 } */ *uap; 529 { 530 char *fstype; 531 struct vfsconf *vfsp = NULL; 532 struct mntarg *ma = NULL; 533 int error; 534 535 /* Kick out MNT_ROOTFS early as it is legal internally */ 536 uap->flags &= ~MNT_ROOTFS; 537 538 if (uap->data == NULL) 539 return (EINVAL); 540 541 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 542 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 543 if (!error) { 544 mtx_lock(&Giant); /* XXX ? */ 545 vfsp = vfs_byname_kld(fstype, td, &error); 546 mtx_unlock(&Giant); 547 } 548 free(fstype, M_TEMP); 549 if (error) 550 return (error); 551 if (vfsp == NULL) 552 return (ENOENT); 553 if (vfsp->vfc_vfsops->vfs_cmount == NULL) 554 return (EOPNOTSUPP); 555 556 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 557 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 558 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 559 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 560 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 561 562 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 563 return (error); 564 } 565 566 567 /* 568 * vfs_domount(): actually attempt a filesystem mount. 569 */ 570 static int 571 vfs_domount( 572 struct thread *td, /* Flags common to all filesystems. */ 573 const char *fstype, /* Filesystem type. */ 574 char *fspath, /* Mount path. */ 575 int fsflags, /* Flags common to all filesystems. */ 576 void *fsdata /* Options local to the filesystem. */ 577 ) 578 { 579 struct vnode *vp; 580 struct mount *mp; 581 struct vfsconf *vfsp; 582 int error, flag = 0, kern_flag = 0; 583 struct vattr va; 584 struct nameidata nd; 585 586 mtx_assert(&Giant, MA_OWNED); 587 588 /* 589 * Be ultra-paranoid about making sure the type and fspath 590 * variables will fit in our mp buffers, including the 591 * terminating NUL. 592 */ 593 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 594 return (ENAMETOOLONG); 595 596 if (jailed(td->td_ucred)) 597 return (EPERM); 598 if (usermount == 0) { 599 if ((error = suser(td)) != 0) 600 return (error); 601 } 602 603 /* 604 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 605 */ 606 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 607 if ((error = suser(td)) != 0) 608 return (error); 609 } 610 /* 611 * Silently enforce MNT_NOSUID and MNT_USER for 612 * unprivileged users. 613 */ 614 if (suser(td) != 0) 615 fsflags |= MNT_NOSUID | MNT_USER; 616 /* 617 * Get vnode to be covered 618 */ 619 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 620 if ((error = namei(&nd)) != 0) 621 return (error); 622 NDFREE(&nd, NDF_ONLY_PNBUF); 623 vp = nd.ni_vp; 624 if (fsflags & MNT_UPDATE) { 625 if ((vp->v_vflag & VV_ROOT) == 0) { 626 vput(vp); 627 return (EINVAL); 628 } 629 mp = vp->v_mount; 630 flag = mp->mnt_flag; 631 kern_flag = mp->mnt_kern_flag; 632 /* 633 * We only allow the filesystem to be reloaded if it 634 * is currently mounted read-only. 635 */ 636 if ((fsflags & MNT_RELOAD) && 637 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 638 vput(vp); 639 return (EOPNOTSUPP); /* Needs translation */ 640 } 641 /* 642 * Only privileged root, or (if MNT_USER is set) the user that 643 * did the original mount is permitted to update it. 644 */ 645 error = vfs_suser(mp, td); 646 if (error) { 647 vput(vp); 648 return (error); 649 } 650 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 651 vput(vp); 652 return (EBUSY); 653 } 654 VI_LOCK(vp); 655 if ((vp->v_iflag & VI_MOUNT) != 0 || 656 vp->v_mountedhere != NULL) { 657 VI_UNLOCK(vp); 658 vfs_unbusy(mp, td); 659 vput(vp); 660 return (EBUSY); 661 } 662 vp->v_iflag |= VI_MOUNT; 663 VI_UNLOCK(vp); 664 mp->mnt_flag |= fsflags & 665 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 666 VOP_UNLOCK(vp, 0, td); 667 mp->mnt_optnew = fsdata; 668 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 669 } else { 670 /* 671 * If the user is not root, ensure that they own the directory 672 * onto which we are attempting to mount. 673 */ 674 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 675 if (error) { 676 vput(vp); 677 return (error); 678 } 679 if (va.va_uid != td->td_ucred->cr_uid) { 680 if ((error = suser(td)) != 0) { 681 vput(vp); 682 return (error); 683 } 684 } 685 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 686 if (error != 0) { 687 vput(vp); 688 return (error); 689 } 690 if (vp->v_type != VDIR) { 691 vput(vp); 692 return (ENOTDIR); 693 } 694 vfsp = vfs_byname_kld(fstype, td, &error); 695 if (vfsp == NULL) { 696 vput(vp); 697 return (error); 698 } 699 VI_LOCK(vp); 700 if ((vp->v_iflag & VI_MOUNT) != 0 || 701 vp->v_mountedhere != NULL) { 702 VI_UNLOCK(vp); 703 vput(vp); 704 return (EBUSY); 705 } 706 vp->v_iflag |= VI_MOUNT; 707 VI_UNLOCK(vp); 708 709 /* 710 * Allocate and initialize the filesystem. 711 */ 712 error = vfs_mount_alloc(vp, vfsp, fspath, td, &mp); 713 if (error) { 714 vput(vp); 715 return (error); 716 } 717 VOP_UNLOCK(vp, 0, td); 718 719 /* XXXMAC: pass to vfs_mount_alloc? */ 720 mp->mnt_optnew = fsdata; 721 } 722 723 /* 724 * Set the mount level flags. 725 */ 726 if (fsflags & MNT_RDONLY) 727 mp->mnt_flag |= MNT_RDONLY; 728 mp->mnt_flag &=~ MNT_UPDATEMASK; 729 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS); 730 /* 731 * Mount the filesystem. 732 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 733 * get. No freeing of cn_pnbuf. 734 */ 735 error = VFS_MOUNT(mp, td); 736 if (!error) { 737 if (mp->mnt_opt != NULL) 738 vfs_freeopts(mp->mnt_opt); 739 mp->mnt_opt = mp->mnt_optnew; 740 VFS_STATFS(mp, &mp->mnt_stat, td); 741 } 742 /* 743 * Prevent external consumers of mount options from reading 744 * mnt_optnew. 745 */ 746 mp->mnt_optnew = NULL; 747 if (mp->mnt_flag & MNT_UPDATE) { 748 mp->mnt_flag &= 749 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 750 if (error) { 751 mp->mnt_flag = flag; 752 mp->mnt_kern_flag = kern_flag; 753 } 754 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 755 if (mp->mnt_syncer == NULL) 756 error = vfs_allocate_syncvnode(mp); 757 } else { 758 if (mp->mnt_syncer != NULL) 759 vrele(mp->mnt_syncer); 760 mp->mnt_syncer = NULL; 761 } 762 vfs_unbusy(mp, td); 763 VI_LOCK(vp); 764 vp->v_iflag &= ~VI_MOUNT; 765 VI_UNLOCK(vp); 766 vrele(vp); 767 return (error); 768 } 769 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 770 /* 771 * Put the new filesystem on the mount list after root. 772 */ 773 cache_purge(vp); 774 if (!error) { 775 struct vnode *newdp; 776 777 VI_LOCK(vp); 778 vp->v_iflag &= ~VI_MOUNT; 779 VI_UNLOCK(vp); 780 vp->v_mountedhere = mp; 781 mtx_lock(&mountlist_mtx); 782 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 783 mtx_unlock(&mountlist_mtx); 784 vfs_event_signal(NULL, VQ_MOUNT, 0); 785 if (VFS_ROOT(mp, &newdp, td)) 786 panic("mount: lost mount"); 787 mountcheckdirs(vp, newdp); 788 vput(newdp); 789 VOP_UNLOCK(vp, 0, td); 790 if ((mp->mnt_flag & MNT_RDONLY) == 0) 791 error = vfs_allocate_syncvnode(mp); 792 vfs_unbusy(mp, td); 793 if (error || (error = VFS_START(mp, 0, td)) != 0) 794 vrele(vp); 795 } else { 796 VI_LOCK(vp); 797 vp->v_iflag &= ~VI_MOUNT; 798 VI_UNLOCK(vp); 799 vfs_mount_destroy(mp, td); 800 vput(vp); 801 } 802 return (error); 803 } 804 805 /* 806 * --------------------------------------------------------------------- 807 * Unmount a filesystem. 808 * 809 * Note: unmount takes a path to the vnode mounted on as argument, 810 * not special file (as before). 811 */ 812 #ifndef _SYS_SYSPROTO_H_ 813 struct unmount_args { 814 char *path; 815 int flags; 816 }; 817 #endif 818 /* ARGSUSED */ 819 int 820 unmount(td, uap) 821 struct thread *td; 822 register struct unmount_args /* { 823 char *path; 824 int flags; 825 } */ *uap; 826 { 827 struct mount *mp; 828 char *pathbuf; 829 int error, id0, id1; 830 831 if (jailed(td->td_ucred)) 832 return (EPERM); 833 if (usermount == 0) { 834 if ((error = suser(td)) != 0) 835 return (error); 836 } 837 838 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 839 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 840 if (error) { 841 free(pathbuf, M_TEMP); 842 return (error); 843 } 844 if (uap->flags & MNT_BYFSID) { 845 /* Decode the filesystem ID. */ 846 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 847 free(pathbuf, M_TEMP); 848 return (EINVAL); 849 } 850 851 mtx_lock(&mountlist_mtx); 852 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 853 if (mp->mnt_stat.f_fsid.val[0] == id0 && 854 mp->mnt_stat.f_fsid.val[1] == id1) 855 break; 856 } 857 mtx_unlock(&mountlist_mtx); 858 } else { 859 mtx_lock(&mountlist_mtx); 860 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 861 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 862 break; 863 } 864 mtx_unlock(&mountlist_mtx); 865 } 866 free(pathbuf, M_TEMP); 867 if (mp == NULL) { 868 /* 869 * Previously we returned ENOENT for a nonexistent path and 870 * EINVAL for a non-mountpoint. We cannot tell these apart 871 * now, so in the !MNT_BYFSID case return the more likely 872 * EINVAL for compatibility. 873 */ 874 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 875 } 876 877 /* 878 * Only privileged root, or (if MNT_USER is set) the user that did the 879 * original mount is permitted to unmount this filesystem. 880 */ 881 error = vfs_suser(mp, td); 882 if (error) 883 return (error); 884 885 /* 886 * Don't allow unmounting the root filesystem. 887 */ 888 if (mp->mnt_flag & MNT_ROOTFS) 889 return (EINVAL); 890 mtx_lock(&Giant); 891 error = dounmount(mp, uap->flags, td); 892 mtx_unlock(&Giant); 893 return (error); 894 } 895 896 /* 897 * Do the actual filesystem unmount. 898 */ 899 int 900 dounmount(mp, flags, td) 901 struct mount *mp; 902 int flags; 903 struct thread *td; 904 { 905 struct vnode *coveredvp, *fsrootvp; 906 int error; 907 int async_flag; 908 909 mtx_assert(&Giant, MA_OWNED); 910 911 MNT_ILOCK(mp); 912 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 913 MNT_IUNLOCK(mp); 914 return (EBUSY); 915 } 916 mp->mnt_kern_flag |= MNTK_UNMOUNT; 917 /* Allow filesystems to detect that a forced unmount is in progress. */ 918 if (flags & MNT_FORCE) 919 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 920 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 921 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 922 if (error) { 923 MNT_ILOCK(mp); 924 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 925 if (mp->mnt_kern_flag & MNTK_MWAIT) 926 wakeup(mp); 927 MNT_IUNLOCK(mp); 928 return (error); 929 } 930 vn_start_write(NULL, &mp, V_WAIT); 931 932 if (mp->mnt_flag & MNT_EXPUBLIC) 933 vfs_setpublicfs(NULL, NULL, NULL); 934 935 vfs_msync(mp, MNT_WAIT); 936 async_flag = mp->mnt_flag & MNT_ASYNC; 937 mp->mnt_flag &= ~MNT_ASYNC; 938 cache_purgevfs(mp); /* remove cache entries for this file sys */ 939 if (mp->mnt_syncer != NULL) 940 vrele(mp->mnt_syncer); 941 /* 942 * For forced unmounts, move process cdir/rdir refs on the fs root 943 * vnode to the covered vnode. For non-forced unmounts we want 944 * such references to cause an EBUSY error. 945 */ 946 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 947 if (mp->mnt_vnodecovered != NULL) 948 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 949 if (fsrootvp == rootvnode) { 950 vrele(rootvnode); 951 rootvnode = NULL; 952 } 953 vput(fsrootvp); 954 } 955 if (((mp->mnt_flag & MNT_RDONLY) || 956 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 957 (flags & MNT_FORCE)) { 958 error = VFS_UNMOUNT(mp, flags, td); 959 } 960 vn_finished_write(mp); 961 if (error) { 962 /* Undo cdir/rdir and rootvnode changes made above. */ 963 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 964 if (mp->mnt_vnodecovered != NULL) 965 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 966 if (rootvnode == NULL) { 967 rootvnode = fsrootvp; 968 vref(rootvnode); 969 } 970 vput(fsrootvp); 971 } 972 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 973 (void) vfs_allocate_syncvnode(mp); 974 MNT_ILOCK(mp); 975 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 976 mp->mnt_flag |= async_flag; 977 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 978 if (mp->mnt_kern_flag & MNTK_MWAIT) 979 wakeup(mp); 980 MNT_IUNLOCK(mp); 981 return (error); 982 } 983 mtx_lock(&mountlist_mtx); 984 TAILQ_REMOVE(&mountlist, mp, mnt_list); 985 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 986 coveredvp->v_mountedhere = NULL; 987 mtx_unlock(&mountlist_mtx); 988 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 989 vfs_mount_destroy(mp, td); 990 if (coveredvp != NULL) 991 vrele(coveredvp); 992 return (0); 993 } 994 995 /* 996 * --------------------------------------------------------------------- 997 * Mounting of root filesystem 998 * 999 */ 1000 1001 static void 1002 set_rootvnode(struct thread *td) 1003 { 1004 struct proc *p; 1005 1006 if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode, td)) 1007 panic("Cannot find root vnode"); 1008 1009 p = td->td_proc; 1010 FILEDESC_LOCK(p->p_fd); 1011 1012 if (p->p_fd->fd_cdir != NULL) 1013 vrele(p->p_fd->fd_cdir); 1014 p->p_fd->fd_cdir = rootvnode; 1015 VREF(rootvnode); 1016 1017 if (p->p_fd->fd_rdir != NULL) 1018 vrele(p->p_fd->fd_rdir); 1019 p->p_fd->fd_rdir = rootvnode; 1020 VREF(rootvnode); 1021 1022 FILEDESC_UNLOCK(p->p_fd); 1023 1024 VOP_UNLOCK(rootvnode, 0, td); 1025 } 1026 1027 /* 1028 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1029 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1030 */ 1031 1032 static struct mount * 1033 devfs_first(void) 1034 { 1035 struct thread *td = curthread; 1036 struct vfsconf *vfsp; 1037 struct mount *mp = NULL; 1038 int error; 1039 1040 vfsp = vfs_byname("devfs"); 1041 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1042 if (vfsp == NULL) 1043 return(NULL); 1044 1045 error = vfs_mount_alloc(NULLVP, vfsp, "/dev", td, &mp); 1046 KASSERT(error == 0, ("vfs_mount_alloc failed %d", error)); 1047 if (error) 1048 return (NULL); 1049 1050 error = VFS_MOUNT(mp, curthread); 1051 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1052 if (error) 1053 return (NULL); 1054 1055 VFS_START(mp, 0, td); 1056 1057 mtx_lock(&mountlist_mtx); 1058 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1059 mtx_unlock(&mountlist_mtx); 1060 1061 set_rootvnode(td); 1062 1063 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1064 if (error) 1065 printf("kern_symlink /dev -> / returns %d\n", error); 1066 1067 return (mp); 1068 } 1069 1070 /* 1071 * Surgically move our devfs to be mounted on /dev. 1072 */ 1073 1074 static void 1075 devfs_fixup(struct thread *td) 1076 { 1077 struct nameidata nd; 1078 int error; 1079 struct vnode *vp, *dvp; 1080 struct mount *mp; 1081 1082 /* Remove our devfs mount from the mountlist and purge the cache */ 1083 mtx_lock(&mountlist_mtx); 1084 mp = TAILQ_FIRST(&mountlist); 1085 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1086 mtx_unlock(&mountlist_mtx); 1087 cache_purgevfs(mp); 1088 1089 VFS_ROOT(mp, &dvp, td); 1090 VI_LOCK(dvp); 1091 dvp->v_iflag &= ~VI_MOUNT; 1092 dvp->v_mountedhere = NULL; 1093 VI_UNLOCK(dvp); 1094 1095 /* Set up the real rootvnode, and purge the cache */ 1096 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1097 set_rootvnode(td); 1098 cache_purgevfs(rootvnode->v_mount); 1099 1100 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1101 error = namei(&nd); 1102 if (error) { 1103 printf("Lookup /dev -> %d\n", error); 1104 return; 1105 } 1106 NDFREE(&nd, NDF_ONLY_PNBUF); 1107 vp = nd.ni_vp; 1108 if (vp->v_type != VDIR) { 1109 vput(vp); 1110 } 1111 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1112 if (error) { 1113 vput(vp); 1114 } 1115 cache_purge(vp); 1116 mp->mnt_vnodecovered = vp; 1117 vp->v_mountedhere = mp; 1118 mtx_lock(&mountlist_mtx); 1119 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1120 mtx_unlock(&mountlist_mtx); 1121 VOP_UNLOCK(vp, 0, td); 1122 vfs_unbusy(mp, td); 1123 vput(dvp); 1124 1125 /* Unlink the no longer needed /dev/dev -> / symlink */ 1126 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1127 } 1128 1129 /* 1130 * Find and mount the root filesystem 1131 */ 1132 void 1133 vfs_mountroot(void) 1134 { 1135 char *cp; 1136 int error, i, asked = 0; 1137 struct mount *mp; 1138 1139 /* 1140 * Wait for GEOM to settle down 1141 */ 1142 DROP_GIANT(); 1143 g_waitidle(); 1144 PICKUP_GIANT(); 1145 1146 mp = devfs_first(); 1147 1148 /* 1149 * We are booted with instructions to prompt for the root filesystem. 1150 */ 1151 if (boothowto & RB_ASKNAME) { 1152 if (!vfs_mountroot_ask()) 1153 return; 1154 asked = 1; 1155 } 1156 1157 /* 1158 * The root filesystem information is compiled in, and we are 1159 * booted with instructions to use it. 1160 */ 1161 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1162 if (!vfs_mountroot_try(ctrootdevname)) 1163 return; 1164 ctrootdevname = NULL; 1165 } 1166 1167 /* 1168 * We've been given the generic "use CDROM as root" flag. This is 1169 * necessary because one media may be used in many different 1170 * devices, so we need to search for them. 1171 */ 1172 if (boothowto & RB_CDROM) { 1173 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1174 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1175 return; 1176 } 1177 } 1178 1179 /* 1180 * Try to use the value read by the loader from /etc/fstab, or 1181 * supplied via some other means. This is the preferred 1182 * mechanism. 1183 */ 1184 cp = getenv("vfs.root.mountfrom"); 1185 if (cp != NULL) { 1186 error = vfs_mountroot_try(cp); 1187 freeenv(cp); 1188 if (!error) 1189 return; 1190 } 1191 1192 /* 1193 * Try values that may have been computed by code during boot 1194 */ 1195 if (!vfs_mountroot_try(rootdevnames[0])) 1196 return; 1197 if (!vfs_mountroot_try(rootdevnames[1])) 1198 return; 1199 1200 /* 1201 * If we (still) have a compiled-in default, try it. 1202 */ 1203 if (ctrootdevname != NULL) 1204 if (!vfs_mountroot_try(ctrootdevname)) 1205 return; 1206 /* 1207 * Everything so far has failed, prompt on the console if we haven't 1208 * already tried that. 1209 */ 1210 if (!asked) 1211 if (!vfs_mountroot_ask()) 1212 return; 1213 1214 panic("Root mount failed, startup aborted."); 1215 } 1216 1217 /* 1218 * Mount (mountfrom) as the root filesystem. 1219 */ 1220 static int 1221 vfs_mountroot_try(const char *mountfrom) 1222 { 1223 struct mount *mp; 1224 char *vfsname, *path; 1225 int error; 1226 char patt[32]; 1227 int s; 1228 1229 vfsname = NULL; 1230 path = NULL; 1231 mp = NULL; 1232 error = EINVAL; 1233 1234 if (mountfrom == NULL) 1235 return (error); /* don't complain */ 1236 1237 s = splcam(); /* Overkill, but annoying without it */ 1238 printf("Trying to mount root from %s\n", mountfrom); 1239 splx(s); 1240 1241 /* parse vfs name and path */ 1242 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1243 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1244 vfsname[0] = path[0] = 0; 1245 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1246 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1247 return (error); 1248 1249 if (path[0] == '\0') 1250 strcpy(path, ROOTNAME); 1251 1252 error = kernel_vmount( 1253 MNT_RDONLY | MNT_ROOTFS, 1254 "fstype", vfsname, 1255 "fspath", "/", 1256 "from", path, 1257 NULL); 1258 if (error == 0) { 1259 mp = TAILQ_FIRST(&mountlist); 1260 1261 /* sanity check system clock against root fs timestamp */ 1262 inittodr(mp->mnt_time); 1263 vfs_unbusy(mp, curthread); 1264 error = VFS_START(mp, 0, curthread); 1265 1266 devfs_fixup(curthread); 1267 } 1268 return (error); 1269 } 1270 1271 /* 1272 * --------------------------------------------------------------------- 1273 * Interactive root filesystem selection code. 1274 */ 1275 1276 static int 1277 vfs_mountroot_ask(void) 1278 { 1279 char name[128]; 1280 1281 for(;;) { 1282 printf("\nManual root filesystem specification:\n"); 1283 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1284 #if defined(__i386__) || defined(__ia64__) 1285 printf(" eg. ufs:da0s1a\n"); 1286 #else 1287 printf(" eg. ufs:/dev/da0a\n"); 1288 #endif 1289 printf(" ? List valid disk boot devices\n"); 1290 printf(" <empty line> Abort manual input\n"); 1291 printf("\nmountroot> "); 1292 gets(name, sizeof(name), 1); 1293 if (name[0] == '\0') 1294 return (1); 1295 if (name[0] == '?') { 1296 printf("\nList of GEOM managed disk devices:\n "); 1297 g_dev_print(); 1298 continue; 1299 } 1300 if (!vfs_mountroot_try(name)) 1301 return (0); 1302 } 1303 } 1304 1305 /* 1306 * --------------------------------------------------------------------- 1307 * Functions for querying mount options/arguments from filesystems. 1308 */ 1309 1310 /* 1311 * Check that no unknown options are given 1312 */ 1313 int 1314 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1315 { 1316 struct vfsopt *opt; 1317 const char **t, *p; 1318 1319 1320 TAILQ_FOREACH(opt, opts, link) { 1321 p = opt->name; 1322 if (p[0] == 'n' && p[1] == 'o') 1323 p += 2; 1324 for(t = global_opts; *t != NULL; t++) 1325 if (!strcmp(*t, p)) 1326 break; 1327 if (*t != NULL) 1328 continue; 1329 for(t = legal; *t != NULL; t++) 1330 if (!strcmp(*t, p)) 1331 break; 1332 if (*t != NULL) 1333 continue; 1334 printf("mount option <%s> is unknown\n", p); 1335 return (EINVAL); 1336 } 1337 return (0); 1338 } 1339 1340 /* 1341 * Get a mount option by its name. 1342 * 1343 * Return 0 if the option was found, ENOENT otherwise. 1344 * If len is non-NULL it will be filled with the length 1345 * of the option. If buf is non-NULL, it will be filled 1346 * with the address of the option. 1347 */ 1348 int 1349 vfs_getopt(opts, name, buf, len) 1350 struct vfsoptlist *opts; 1351 const char *name; 1352 void **buf; 1353 int *len; 1354 { 1355 struct vfsopt *opt; 1356 1357 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1358 1359 TAILQ_FOREACH(opt, opts, link) { 1360 if (strcmp(name, opt->name) == 0) { 1361 if (len != NULL) 1362 *len = opt->len; 1363 if (buf != NULL) 1364 *buf = opt->value; 1365 return (0); 1366 } 1367 } 1368 return (ENOENT); 1369 } 1370 1371 char * 1372 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1373 { 1374 struct vfsopt *opt; 1375 1376 *error = 0; 1377 TAILQ_FOREACH(opt, opts, link) { 1378 if (strcmp(name, opt->name) != 0) 1379 continue; 1380 if (((char *)opt->value)[opt->len - 1] != '\0') { 1381 *error = EINVAL; 1382 return (NULL); 1383 } 1384 return (opt->value); 1385 } 1386 return (NULL); 1387 } 1388 1389 int 1390 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1391 { 1392 struct vfsopt *opt; 1393 1394 TAILQ_FOREACH(opt, opts, link) { 1395 if (strcmp(name, opt->name) == 0) { 1396 if (w != NULL) 1397 *w |= val; 1398 return (1); 1399 } 1400 } 1401 if (w != NULL) 1402 *w &= ~val; 1403 return (0); 1404 } 1405 1406 int 1407 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1408 { 1409 va_list ap; 1410 struct vfsopt *opt; 1411 int ret; 1412 1413 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1414 1415 TAILQ_FOREACH(opt, opts, link) { 1416 if (strcmp(name, opt->name) != 0) 1417 continue; 1418 if (((char *)opt->value)[opt->len - 1] != '\0') 1419 return (0); 1420 va_start(ap, fmt); 1421 ret = vsscanf(opt->value, fmt, ap); 1422 va_end(ap); 1423 return (ret); 1424 } 1425 return (0); 1426 } 1427 1428 /* 1429 * Find and copy a mount option. 1430 * 1431 * The size of the buffer has to be specified 1432 * in len, if it is not the same length as the 1433 * mount option, EINVAL is returned. 1434 * Returns ENOENT if the option is not found. 1435 */ 1436 int 1437 vfs_copyopt(opts, name, dest, len) 1438 struct vfsoptlist *opts; 1439 const char *name; 1440 void *dest; 1441 int len; 1442 { 1443 struct vfsopt *opt; 1444 1445 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1446 1447 TAILQ_FOREACH(opt, opts, link) { 1448 if (strcmp(name, opt->name) == 0) { 1449 if (len != opt->len) 1450 return (EINVAL); 1451 bcopy(opt->value, dest, opt->len); 1452 return (0); 1453 } 1454 } 1455 return (ENOENT); 1456 } 1457 1458 /* 1459 * This is a helper function for filesystems to traverse their 1460 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1461 */ 1462 1463 struct vnode * 1464 __mnt_vnode_next(struct vnode **nvp, struct mount *mp) 1465 { 1466 struct vnode *vp; 1467 1468 mtx_assert(&mp->mnt_mtx, MA_OWNED); 1469 1470 vp = *nvp; 1471 /* Check if we are done */ 1472 if (vp == NULL) 1473 return (NULL); 1474 /* If our next vnode is no longer ours, start over */ 1475 if (vp->v_mount != mp) 1476 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1477 /* Save pointer to next vnode in list */ 1478 if (vp != NULL) 1479 *nvp = TAILQ_NEXT(vp, v_nmntvnodes); 1480 else 1481 *nvp = NULL; 1482 return (vp); 1483 } 1484 1485 int 1486 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 1487 { 1488 int error; 1489 1490 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 1491 if (sbp != &mp->mnt_stat) 1492 *sbp = mp->mnt_stat; 1493 return (error); 1494 } 1495 1496 void 1497 vfs_mountedfrom(struct mount *mp, const char *from) 1498 { 1499 1500 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1501 strlcpy(mp->mnt_stat.f_mntfromname, from, 1502 sizeof mp->mnt_stat.f_mntfromname); 1503 } 1504 1505 /* 1506 * --------------------------------------------------------------------- 1507 * This is the api for building mount args and mounting filesystems from 1508 * inside the kernel. 1509 * 1510 * The API works by accumulation of individual args. First error is 1511 * latched. 1512 * 1513 * XXX: should be documented in new manpage kernel_mount(9) 1514 */ 1515 1516 /* A memory allocation which must be freed when we are done */ 1517 struct mntaarg { 1518 SLIST_ENTRY(mntaarg) next; 1519 }; 1520 1521 /* The header for the mount arguments */ 1522 struct mntarg { 1523 struct iovec *v; 1524 int len; 1525 int error; 1526 SLIST_HEAD(, mntaarg) list; 1527 }; 1528 1529 /* 1530 * Add a boolean argument. 1531 * 1532 * flag is the boolean value. 1533 * name must start with "no". 1534 */ 1535 struct mntarg * 1536 mount_argb(struct mntarg *ma, int flag, const char *name) 1537 { 1538 1539 KASSERT(name[0] == 'n' && name[1] == 'o', 1540 ("mount_argb(...,%s): name must start with 'no'", name)); 1541 1542 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1543 } 1544 1545 /* 1546 * Add an argument printf style 1547 */ 1548 struct mntarg * 1549 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1550 { 1551 va_list ap; 1552 struct mntaarg *maa; 1553 struct sbuf *sb; 1554 int len; 1555 1556 if (ma == NULL) { 1557 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1558 SLIST_INIT(&ma->list); 1559 } 1560 if (ma->error) 1561 return (ma); 1562 1563 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1564 M_MOUNT, M_WAITOK); 1565 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1566 ma->v[ma->len].iov_len = strlen(name) + 1; 1567 ma->len++; 1568 1569 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 1570 va_start(ap, fmt); 1571 sbuf_vprintf(sb, fmt, ap); 1572 va_end(ap); 1573 sbuf_finish(sb); 1574 len = sbuf_len(sb) + 1; 1575 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1576 SLIST_INSERT_HEAD(&ma->list, maa, next); 1577 bcopy(sbuf_data(sb), maa + 1, len); 1578 sbuf_delete(sb); 1579 1580 ma->v[ma->len].iov_base = maa + 1; 1581 ma->v[ma->len].iov_len = len; 1582 ma->len++; 1583 1584 return (ma); 1585 } 1586 1587 /* 1588 * Add an argument which is a userland string. 1589 */ 1590 struct mntarg * 1591 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1592 { 1593 struct mntaarg *maa; 1594 char *tbuf; 1595 1596 if (val == NULL) 1597 return (ma); 1598 if (ma == NULL) { 1599 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1600 SLIST_INIT(&ma->list); 1601 } 1602 if (ma->error) 1603 return (ma); 1604 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1605 SLIST_INSERT_HEAD(&ma->list, maa, next); 1606 tbuf = (void *)(maa + 1); 1607 ma->error = copyinstr(val, tbuf, len, NULL); 1608 return (mount_arg(ma, name, tbuf, -1)); 1609 } 1610 1611 /* 1612 * Plain argument. 1613 * 1614 * If length is -1, use printf. 1615 */ 1616 struct mntarg * 1617 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1618 { 1619 1620 if (ma == NULL) { 1621 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1622 SLIST_INIT(&ma->list); 1623 } 1624 if (ma->error) 1625 return (ma); 1626 1627 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1628 M_MOUNT, M_WAITOK); 1629 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1630 ma->v[ma->len].iov_len = strlen(name) + 1; 1631 ma->len++; 1632 1633 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1634 if (len < 0) 1635 ma->v[ma->len].iov_len = strlen(val) + 1; 1636 else 1637 ma->v[ma->len].iov_len = len; 1638 ma->len++; 1639 return (ma); 1640 } 1641 1642 /* 1643 * Free a mntarg structure 1644 */ 1645 void 1646 free_mntarg(struct mntarg *ma) 1647 { 1648 struct mntaarg *maa; 1649 1650 while (!SLIST_EMPTY(&ma->list)) { 1651 maa = SLIST_FIRST(&ma->list); 1652 SLIST_REMOVE_HEAD(&ma->list, next); 1653 free(maa, M_MOUNT); 1654 } 1655 free(ma->v, M_MOUNT); 1656 free(ma, M_MOUNT); 1657 } 1658 1659 /* 1660 * Mount a filesystem 1661 */ 1662 int 1663 kernel_mount(struct mntarg *ma, int flags) 1664 { 1665 struct uio auio; 1666 int error; 1667 1668 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 1669 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 1670 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 1671 1672 auio.uio_iov = ma->v; 1673 auio.uio_iovcnt = ma->len; 1674 auio.uio_segflg = UIO_SYSSPACE; 1675 1676 error = ma->error; 1677 if (!error) 1678 error = vfs_donmount(curthread, flags, &auio); 1679 free_mntarg(ma); 1680 return (error); 1681 } 1682 1683 /* 1684 * A printflike function to mount a filesystem. 1685 */ 1686 int 1687 kernel_vmount(int flags, ...) 1688 { 1689 struct mntarg *ma = NULL; 1690 va_list ap; 1691 const char *cp; 1692 const void *vp; 1693 int error; 1694 1695 va_start(ap, flags); 1696 for (;;) { 1697 cp = va_arg(ap, const char *); 1698 if (cp == NULL) 1699 break; 1700 vp = va_arg(ap, const void *); 1701 ma = mount_arg(ma, cp, vp, -1); 1702 } 1703 va_end(ap); 1704 1705 error = kernel_mount(ma, flags); 1706 return (error); 1707 } 1708