vfs_mount.c revision 127058
1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * Copyright (c) 1999 Michael Smith 39 * All rights reserved. 40 * Copyright (c) 1999 Poul-Henning Kamp 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 */ 64 65#include <sys/cdefs.h> 66__FBSDID("$FreeBSD: head/sys/kern/vfs_mount.c 127058 2004-03-16 08:59:37Z tjr $"); 67 68#include <sys/param.h> 69#include <sys/conf.h> 70#include <sys/cons.h> 71#include <sys/jail.h> 72#include <sys/kernel.h> 73#include <sys/linker.h> 74#include <sys/mac.h> 75#include <sys/malloc.h> 76#include <sys/mount.h> 77#include <sys/mutex.h> 78#include <sys/namei.h> 79#include <sys/proc.h> 80#include <sys/filedesc.h> 81#include <sys/reboot.h> 82#include <sys/sysproto.h> 83#include <sys/sx.h> 84#include <sys/sysctl.h> 85#include <sys/sysent.h> 86#include <sys/systm.h> 87#include <sys/vnode.h> 88 89#include <geom/geom.h> 90 91#include <machine/stdarg.h> 92 93#include "opt_rootdevname.h" 94#include "opt_ddb.h" 95#include "opt_mac.h" 96 97#ifdef DDB 98#include <ddb/ddb.h> 99#endif 100 101#define ROOTNAME "root_device" 102#define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 103 104static void checkdirs(struct vnode *olddp, struct vnode *newdp); 105static void gets(char *cp); 106static int vfs_domount(struct thread *td, const char *fstype, 107 char *fspath, int fsflags, void *fsdata, int compat); 108static int vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 109 const char *fspath, struct thread *td, struct mount **mpp); 110static int vfs_mountroot_ask(void); 111static int vfs_mountroot_try(char *mountfrom); 112 113static int usermount = 0; /* if 1, non-root can mount fs. */ 114SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, ""); 115 116MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 117 118/* List of mounted filesystems. */ 119struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 120 121/* For any iteration/modification of mountlist */ 122struct mtx mountlist_mtx; 123 124/* 125 * The vnode of the system's root (/ in the filesystem, without chroot 126 * active.) 127 */ 128struct vnode *rootvnode; 129 130/* 131 * The root filesystem is detailed in the kernel environment variable 132 * vfs.root.mountfrom, which is expected to be in the general format 133 * 134 * <vfsname>:[<path>] 135 * vfsname := the name of a VFS known to the kernel and capable 136 * of being mounted as root 137 * path := disk device name or other data used by the filesystem 138 * to locate its physical store 139 */ 140 141/* 142 * The root specifiers we will try if RB_CDROM is specified. 143 */ 144static char *cdrom_rootdevnames[] = { 145 "cd9660:cd0", 146 "cd9660:acd0", 147 NULL 148}; 149 150/* legacy find-root code */ 151char *rootdevnames[2] = {NULL, NULL}; 152static int setrootbyname(char *name); 153dev_t rootdev = NODEV; 154 155/* 156 * Has to be dynamic as the value of rootdev can change; however, it can't 157 * change after the root is mounted, so a user process can't access this 158 * sysctl until after the value is unchangeable. 159 */ 160static int 161sysctl_rootdev(SYSCTL_HANDLER_ARGS) 162{ 163 int error; 164 165 /* _RD prevents this from happening. */ 166 KASSERT(req->newptr == NULL, ("Attempt to change root device name")); 167 168 if (rootdev != NODEV) 169 error = sysctl_handle_string(oidp, rootdev->si_name, 0, req); 170 else 171 error = sysctl_handle_string(oidp, "", 0, req); 172 173 return (error); 174} 175 176SYSCTL_PROC(_kern, OID_AUTO, rootdev, CTLTYPE_STRING | CTLFLAG_RD, 177 0, 0, sysctl_rootdev, "A", "Root file system device"); 178 179/* Remove one mount option. */ 180static void 181vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 182{ 183 184 TAILQ_REMOVE(opts, opt, link); 185 free(opt->name, M_MOUNT); 186 if (opt->value != NULL) 187 free(opt->value, M_MOUNT); 188#ifdef INVARIANTS 189 else if (opt->len != 0) 190 panic("%s: mount option with NULL value but length != 0", 191 __func__); 192#endif 193 free(opt, M_MOUNT); 194} 195 196/* Release all resources related to the mount options. */ 197static void 198vfs_freeopts(struct vfsoptlist *opts) 199{ 200 struct vfsopt *opt; 201 202 while (!TAILQ_EMPTY(opts)) { 203 opt = TAILQ_FIRST(opts); 204 vfs_freeopt(opts, opt); 205 } 206 free(opts, M_MOUNT); 207} 208 209/* 210 * If a mount option is specified several times, 211 * (with or without the "no" prefix) only keep 212 * the last occurence of it. 213 */ 214static void 215vfs_sanitizeopts(struct vfsoptlist *opts) 216{ 217 struct vfsopt *opt, *opt2, *tmp; 218 int noopt; 219 220 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 221 if (strncmp(opt->name, "no", 2) == 0) 222 noopt = 1; 223 else 224 noopt = 0; 225 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 226 while (opt2 != NULL) { 227 if (strcmp(opt2->name, opt->name) == 0 || 228 (noopt && strcmp(opt->name + 2, opt2->name) == 0) || 229 (!noopt && strncmp(opt2->name, "no", 2) == 0 && 230 strcmp(opt2->name + 2, opt->name) == 0)) { 231 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 232 vfs_freeopt(opts, opt2); 233 opt2 = tmp; 234 } else { 235 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 236 } 237 } 238 } 239} 240 241/* 242 * Build a linked list of mount options from a struct uio. 243 */ 244static int 245vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 246{ 247 struct vfsoptlist *opts; 248 struct vfsopt *opt; 249 size_t memused; 250 unsigned int i, iovcnt; 251 int error, namelen, optlen; 252 253 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 254 TAILQ_INIT(opts); 255 memused = 0; 256 iovcnt = auio->uio_iovcnt; 257 for (i = 0; i < iovcnt; i += 2) { 258 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 259 namelen = auio->uio_iov[i].iov_len; 260 optlen = auio->uio_iov[i + 1].iov_len; 261 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 262 opt->value = NULL; 263 opt->len = optlen; 264 265 /* 266 * Do this early, so jumps to "bad" will free the current 267 * option. 268 */ 269 TAILQ_INSERT_TAIL(opts, opt, link); 270 memused += sizeof(struct vfsopt) + optlen + namelen; 271 272 /* 273 * Avoid consuming too much memory, and attempts to overflow 274 * memused. 275 */ 276 if (memused > VFS_MOUNTARG_SIZE_MAX || 277 optlen > VFS_MOUNTARG_SIZE_MAX || 278 namelen > VFS_MOUNTARG_SIZE_MAX) { 279 error = EINVAL; 280 goto bad; 281 } 282 283 if (auio->uio_segflg == UIO_SYSSPACE) { 284 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 285 } else { 286 error = copyin(auio->uio_iov[i].iov_base, opt->name, 287 namelen); 288 if (error) 289 goto bad; 290 } 291 /* Ensure names are null-terminated strings. */ 292 if (opt->name[namelen - 1] != '\0') { 293 error = EINVAL; 294 goto bad; 295 } 296 if (optlen != 0) { 297 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 298 if (auio->uio_segflg == UIO_SYSSPACE) { 299 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 300 optlen); 301 } else { 302 error = copyin(auio->uio_iov[i + 1].iov_base, 303 opt->value, optlen); 304 if (error) 305 goto bad; 306 } 307 } 308 } 309 vfs_sanitizeopts(opts); 310 *options = opts; 311 return (0); 312bad: 313 vfs_freeopts(opts); 314 return (error); 315} 316 317/* 318 * Merge the old mount options with the new ones passed 319 * in the MNT_UPDATE case. 320 */ 321static void 322vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 323{ 324 struct vfsopt *opt, *opt2, *new; 325 326 TAILQ_FOREACH(opt, opts, link) { 327 /* 328 * Check that this option hasn't been redefined 329 * nor cancelled with a "no" mount option. 330 */ 331 opt2 = TAILQ_FIRST(toopts); 332 while (opt2 != NULL) { 333 if (strcmp(opt2->name, opt->name) == 0) 334 goto next; 335 if (strncmp(opt2->name, "no", 2) == 0 && 336 strcmp(opt2->name + 2, opt->name) == 0) { 337 vfs_freeopt(toopts, opt2); 338 goto next; 339 } 340 opt2 = TAILQ_NEXT(opt2, link); 341 } 342 /* We want this option, duplicate it. */ 343 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 344 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 345 strcpy(new->name, opt->name); 346 if (opt->len != 0) { 347 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 348 bcopy(opt->value, new->value, opt->len); 349 } else { 350 new->value = NULL; 351 } 352 new->len = opt->len; 353 TAILQ_INSERT_TAIL(toopts, new, link); 354next: 355 continue; 356 } 357} 358 359/* 360 * New mount API. 361 */ 362int 363nmount(td, uap) 364 struct thread *td; 365 struct nmount_args /* { 366 struct iovec *iovp; 367 unsigned int iovcnt; 368 int flags; 369 } */ *uap; 370{ 371 struct uio auio; 372 struct iovec *iov, *needfree; 373 struct iovec aiov[UIO_SMALLIOV]; 374 unsigned int i; 375 int error; 376 u_int iovlen, iovcnt; 377 378 iovcnt = uap->iovcnt; 379 iovlen = iovcnt * sizeof (struct iovec); 380 /* 381 * Check that we have an even number of iovec's 382 * and that we have at least two options. 383 */ 384 if ((iovcnt & 1) || (iovcnt < 4) || (iovcnt > UIO_MAXIOV)) 385 return (EINVAL); 386 387 if (iovcnt > UIO_SMALLIOV) { 388 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); 389 needfree = iov; 390 } else { 391 iov = aiov; 392 needfree = NULL; 393 } 394 auio.uio_iov = iov; 395 auio.uio_iovcnt = iovcnt; 396 auio.uio_segflg = UIO_USERSPACE; 397 if ((error = copyin(uap->iovp, iov, iovlen))) 398 goto finish; 399 400 for (i = 0; i < iovcnt; i++) { 401 if (iov->iov_len > MMAXOPTIONLEN) { 402 error = EINVAL; 403 goto finish; 404 } 405 iov++; 406 } 407 error = vfs_nmount(td, uap->flags, &auio); 408finish: 409 if (needfree != NULL) 410 free(needfree, M_TEMP); 411 return (error); 412} 413 414int 415kernel_mount(iovp, iovcnt, flags) 416 struct iovec *iovp; 417 unsigned int iovcnt; 418 int flags; 419{ 420 struct uio auio; 421 int error; 422 423 /* 424 * Check that we have an even number of iovec's 425 * and that we have at least two options. 426 */ 427 if ((iovcnt & 1) || (iovcnt < 4)) 428 return (EINVAL); 429 430 auio.uio_iov = iovp; 431 auio.uio_iovcnt = iovcnt; 432 auio.uio_segflg = UIO_SYSSPACE; 433 434 error = vfs_nmount(curthread, flags, &auio); 435 return (error); 436} 437 438int 439kernel_vmount(int flags, ...) 440{ 441 struct iovec *iovp; 442 struct uio auio; 443 va_list ap; 444 unsigned int iovcnt, iovlen, len; 445 const char *cp; 446 char *buf, *pos; 447 size_t n; 448 int error, i; 449 450 len = 0; 451 va_start(ap, flags); 452 for (iovcnt = 0; (cp = va_arg(ap, const char *)) != NULL; iovcnt++) 453 len += strlen(cp) + 1; 454 va_end(ap); 455 456 if (iovcnt < 4 || iovcnt & 1) 457 return (EINVAL); 458 459 iovlen = iovcnt * sizeof (struct iovec); 460 MALLOC(iovp, struct iovec *, iovlen, M_MOUNT, M_WAITOK); 461 MALLOC(buf, char *, len, M_MOUNT, M_WAITOK); 462 pos = buf; 463 va_start(ap, flags); 464 for (i = 0; i < iovcnt; i++) { 465 cp = va_arg(ap, const char *); 466 copystr(cp, pos, len - (pos - buf), &n); 467 iovp[i].iov_base = pos; 468 iovp[i].iov_len = n; 469 pos += n; 470 } 471 va_end(ap); 472 473 auio.uio_iov = iovp; 474 auio.uio_iovcnt = iovcnt; 475 auio.uio_segflg = UIO_SYSSPACE; 476 477 error = vfs_nmount(curthread, flags, &auio); 478 FREE(iovp, M_MOUNT); 479 FREE(buf, M_MOUNT); 480 return (error); 481} 482 483/* 484 * Allocate and initialize the mount point struct. 485 */ 486static int 487vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 488 const char *fspath, struct thread *td, struct mount **mpp) 489{ 490 struct mount *mp; 491 492 mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 493 TAILQ_INIT(&mp->mnt_nvnodelist); 494 mp->mnt_nvnodelistsize = 0; 495 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 496 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 497 vfs_busy(mp, LK_NOWAIT, 0, td); 498 mp->mnt_op = vfsp->vfc_vfsops; 499 mp->mnt_vfc = vfsp; 500 vfsp->vfc_refcount++; 501 mp->mnt_stat.f_type = vfsp->vfc_typenum; 502 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 503 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 504 mp->mnt_vnodecovered = vp; 505 mp->mnt_cred = crdup(td->td_ucred); 506 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 507 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 508 mp->mnt_iosize_max = DFLTPHYS; 509#ifdef MAC 510 mac_init_mount(mp); 511 mac_create_mount(td->td_ucred, mp); 512#endif 513 *mpp = mp; 514 return (0); 515} 516 517/* 518 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 519 */ 520void 521vfs_mount_destroy(struct mount *mp, struct thread *td) 522{ 523 524 mp->mnt_vfc->vfc_refcount--; 525 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 526 panic("unmount: dangling vnode"); 527 vfs_unbusy(mp,td); 528 lockdestroy(&mp->mnt_lock); 529 mtx_destroy(&mp->mnt_mtx); 530 if (mp->mnt_kern_flag & MNTK_MWAIT) 531 wakeup(mp); 532#ifdef MAC 533 mac_destroy_mount(mp); 534#endif 535 if (mp->mnt_opt != NULL) 536 vfs_freeopts(mp->mnt_opt); 537 crfree(mp->mnt_cred); 538 free(mp, M_MOUNT); 539} 540 541int 542vfs_nmount(struct thread *td, int fsflags, struct uio *fsoptions) 543{ 544 struct vfsoptlist *optlist; 545 char *fstype, *fspath; 546 int error, fstypelen, fspathlen; 547 548 error = vfs_buildopts(fsoptions, &optlist); 549 if (error) 550 return (error); 551 552 /* 553 * We need these two options before the others, 554 * and they are mandatory for any filesystem. 555 * Ensure they are NUL terminated as well. 556 */ 557 fstypelen = 0; 558 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 559 if (error || fstype[fstypelen - 1] != '\0') { 560 error = EINVAL; 561 goto bail; 562 } 563 fspathlen = 0; 564 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 565 if (error || fspath[fspathlen - 1] != '\0') { 566 error = EINVAL; 567 goto bail; 568 } 569 570 /* 571 * Be ultra-paranoid about making sure the type and fspath 572 * variables will fit in our mp buffers, including the 573 * terminating NUL. 574 */ 575 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 576 error = ENAMETOOLONG; 577 goto bail; 578 } 579 580 error = vfs_domount(td, fstype, fspath, fsflags, optlist, 0); 581bail: 582 if (error) 583 vfs_freeopts(optlist); 584 return (error); 585} 586 587/* 588 * Old mount API. 589 */ 590#ifndef _SYS_SYSPROTO_H_ 591struct mount_args { 592 char *type; 593 char *path; 594 int flags; 595 caddr_t data; 596}; 597#endif 598/* ARGSUSED */ 599int 600mount(td, uap) 601 struct thread *td; 602 struct mount_args /* { 603 char *type; 604 char *path; 605 int flags; 606 caddr_t data; 607 } */ *uap; 608{ 609 char *fstype; 610 char *fspath; 611 int error; 612 613 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 614 fspath = malloc(MNAMELEN, M_TEMP, M_WAITOK); 615 616 /* 617 * vfs_mount() actually takes a kernel string for `type' and 618 * `path' now, so extract them. 619 */ 620 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 621 if (error == 0) 622 error = copyinstr(uap->path, fspath, MNAMELEN, NULL); 623 if (error == 0) 624 error = vfs_domount(td, fstype, fspath, uap->flags, 625 uap->data, 1); 626 free(fstype, M_TEMP); 627 free(fspath, M_TEMP); 628 return (error); 629} 630 631/* 632 * vfs_mount(): actually attempt a filesystem mount. 633 * 634 * This routine is designed to be a "generic" entry point for routines 635 * that wish to mount a filesystem. All parameters except `fsdata' are 636 * pointers into kernel space. `fsdata' is currently still a pointer 637 * into userspace. 638 */ 639int 640vfs_mount(td, fstype, fspath, fsflags, fsdata) 641 struct thread *td; 642 const char *fstype; 643 char *fspath; 644 int fsflags; 645 void *fsdata; 646{ 647 648 return (vfs_domount(td, fstype, fspath, fsflags, fsdata, 1)); 649} 650 651/* 652 * vfs_domount(): actually attempt a filesystem mount. 653 */ 654static int 655vfs_domount( 656 struct thread *td, /* Flags common to all filesystems. */ 657 const char *fstype, /* Filesystem type. */ 658 char *fspath, /* Mount path. */ 659 int fsflags, /* Flags common to all filesystems. */ 660 void *fsdata, /* Options local to the filesystem. */ 661 int compat /* Invocation from compat syscall. */ 662 ) 663{ 664 linker_file_t lf; 665 struct vnode *vp; 666 struct mount *mp; 667 struct vfsconf *vfsp; 668 int error, flag = 0, kern_flag = 0; 669 struct vattr va; 670 struct nameidata nd; 671 672 /* 673 * Be ultra-paranoid about making sure the type and fspath 674 * variables will fit in our mp buffers, including the 675 * terminating NUL. 676 */ 677 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 678 return (ENAMETOOLONG); 679 680 /* mount(2) is not permitted inside the jail. */ 681 if (jailed(td->td_ucred)) 682 return (EPERM); 683 684 if (usermount == 0) { 685 error = suser(td); 686 if (error) 687 return (error); 688 } 689 /* 690 * Do not allow NFS export by non-root users. 691 */ 692 if (fsflags & MNT_EXPORTED) { 693 error = suser(td); 694 if (error) 695 return (error); 696 } 697 /* 698 * Silently enforce MNT_NOSUID, MNT_NODEV and MNT_USER 699 * for unprivileged users. 700 */ 701 if (suser(td)) 702 fsflags |= MNT_NOSUID | MNT_NODEV | MNT_USER; 703 /* 704 * Get vnode to be covered 705 */ 706 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 707 if ((error = namei(&nd)) != 0) 708 return (error); 709 NDFREE(&nd, NDF_ONLY_PNBUF); 710 vp = nd.ni_vp; 711 if (fsflags & MNT_UPDATE) { 712 if ((vp->v_vflag & VV_ROOT) == 0) { 713 vput(vp); 714 return (EINVAL); 715 } 716 mp = vp->v_mount; 717 flag = mp->mnt_flag; 718 kern_flag = mp->mnt_kern_flag; 719 /* 720 * We only allow the filesystem to be reloaded if it 721 * is currently mounted read-only. 722 */ 723 if ((fsflags & MNT_RELOAD) && 724 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 725 vput(vp); 726 return (EOPNOTSUPP); /* Needs translation */ 727 } 728 /* 729 * Only root, or the user that did the original mount is 730 * permitted to update it. 731 */ 732 if ((mp->mnt_flag & MNT_USER) != 0) { 733 if (mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 734 if ((error = suser(td)) != 0) { 735 vput(vp); 736 return (error); 737 } 738 } 739 } else { 740 if ((error = suser(td)) != 0) { 741 vput(vp); 742 return (error); 743 } 744 } 745 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 746 vput(vp); 747 return (EBUSY); 748 } 749 VI_LOCK(vp); 750 if ((vp->v_iflag & VI_MOUNT) != 0 || 751 vp->v_mountedhere != NULL) { 752 VI_UNLOCK(vp); 753 vfs_unbusy(mp, td); 754 vput(vp); 755 return (EBUSY); 756 } 757 vp->v_iflag |= VI_MOUNT; 758 VI_UNLOCK(vp); 759 mp->mnt_flag |= fsflags & 760 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT); 761 VOP_UNLOCK(vp, 0, td); 762 if (compat == 0) { 763 mp->mnt_optnew = fsdata; 764 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 765 } 766 goto update; 767 } 768 /* 769 * If the user is not root, ensure that they own the directory 770 * onto which we are attempting to mount. 771 */ 772 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 773 if (error) { 774 vput(vp); 775 return (error); 776 } 777 if (va.va_uid != td->td_ucred->cr_uid) { 778 error = suser(td); 779 if (error) { 780 vput(vp); 781 return (error); 782 } 783 } 784 if ((error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0)) != 0) { 785 vput(vp); 786 return (error); 787 } 788 if (vp->v_type != VDIR) { 789 vput(vp); 790 return (ENOTDIR); 791 } 792 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 793 if (!strcmp(vfsp->vfc_name, fstype)) 794 break; 795 if (vfsp == NULL) { 796 /* Only load modules for root (very important!). */ 797 error = suser(td); 798 if (error) { 799 vput(vp); 800 return (error); 801 } 802 error = securelevel_gt(td->td_ucred, 0); 803 if (error) { 804 vput(vp); 805 return (error); 806 } 807 error = linker_load_module(NULL, fstype, NULL, NULL, &lf); 808 if (error || lf == NULL) { 809 vput(vp); 810 if (lf == NULL) 811 error = ENODEV; 812 return (error); 813 } 814 lf->userrefs++; 815 /* Look up again to see if the VFS was loaded. */ 816 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 817 if (!strcmp(vfsp->vfc_name, fstype)) 818 break; 819 if (vfsp == NULL) { 820 lf->userrefs--; 821 linker_file_unload(lf); 822 vput(vp); 823 return (ENODEV); 824 } 825 } 826 VI_LOCK(vp); 827 if ((vp->v_iflag & VI_MOUNT) != 0 || 828 vp->v_mountedhere != NULL) { 829 VI_UNLOCK(vp); 830 vput(vp); 831 return (EBUSY); 832 } 833 vp->v_iflag |= VI_MOUNT; 834 VI_UNLOCK(vp); 835 836 /* 837 * Allocate and initialize the filesystem. 838 */ 839 error = vfs_mount_alloc(vp, vfsp, fspath, td, &mp); 840 if (error) { 841 vput(vp); 842 return (error); 843 } 844 VOP_UNLOCK(vp, 0, td); 845 846 /* XXXMAC: pass to vfs_mount_alloc? */ 847 if (compat == 0) 848 mp->mnt_optnew = fsdata; 849update: 850 /* 851 * Check if the fs implements the type VFS_[N]MOUNT() 852 * function we are looking for. 853 */ 854 if ((compat == 0) == (mp->mnt_op->vfs_mount != NULL)) { 855 printf("%s doesn't support the %s mount syscall\n", 856 mp->mnt_vfc->vfc_name, compat? "old" : "new"); 857 VI_LOCK(vp); 858 vp->v_iflag &= ~VI_MOUNT; 859 VI_UNLOCK(vp); 860 if (mp->mnt_flag & MNT_UPDATE) 861 vfs_unbusy(mp, td); 862 else 863 vfs_mount_destroy(mp, td); 864 vrele(vp); 865 return (EOPNOTSUPP); 866 } 867 868 /* 869 * Set the mount level flags. 870 */ 871 if (fsflags & MNT_RDONLY) 872 mp->mnt_flag |= MNT_RDONLY; 873 else if (mp->mnt_flag & MNT_RDONLY) 874 mp->mnt_kern_flag |= MNTK_WANTRDWR; 875 mp->mnt_flag &=~ MNT_UPDATEMASK; 876 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE); 877 /* 878 * Mount the filesystem. 879 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 880 * get. No freeing of cn_pnbuf. 881 */ 882 error = compat? VFS_MOUNT(mp, fspath, fsdata, &nd, td) : 883 VFS_NMOUNT(mp, &nd, td); 884 if (!error) { 885 if (mp->mnt_opt != NULL) 886 vfs_freeopts(mp->mnt_opt); 887 mp->mnt_opt = mp->mnt_optnew; 888 } 889 /* 890 * Prevent external consumers of mount options from reading 891 * mnt_optnew. 892 */ 893 mp->mnt_optnew = NULL; 894 if (mp->mnt_flag & MNT_UPDATE) { 895 if (mp->mnt_kern_flag & MNTK_WANTRDWR) 896 mp->mnt_flag &= ~MNT_RDONLY; 897 mp->mnt_flag &=~ 898 (MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 899 mp->mnt_kern_flag &=~ MNTK_WANTRDWR; 900 if (error) { 901 mp->mnt_flag = flag; 902 mp->mnt_kern_flag = kern_flag; 903 } 904 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 905 if (mp->mnt_syncer == NULL) 906 error = vfs_allocate_syncvnode(mp); 907 } else { 908 if (mp->mnt_syncer != NULL) 909 vrele(mp->mnt_syncer); 910 mp->mnt_syncer = NULL; 911 } 912 vfs_unbusy(mp, td); 913 VI_LOCK(vp); 914 vp->v_iflag &= ~VI_MOUNT; 915 VI_UNLOCK(vp); 916 vrele(vp); 917 return (error); 918 } 919 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 920 /* 921 * Put the new filesystem on the mount list after root. 922 */ 923 cache_purge(vp); 924 if (!error) { 925 struct vnode *newdp; 926 927 VI_LOCK(vp); 928 vp->v_iflag &= ~VI_MOUNT; 929 VI_UNLOCK(vp); 930 vp->v_mountedhere = mp; 931 mtx_lock(&mountlist_mtx); 932 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 933 mtx_unlock(&mountlist_mtx); 934 if (VFS_ROOT(mp, &newdp)) 935 panic("mount: lost mount"); 936 checkdirs(vp, newdp); 937 vput(newdp); 938 VOP_UNLOCK(vp, 0, td); 939 if ((mp->mnt_flag & MNT_RDONLY) == 0) 940 error = vfs_allocate_syncvnode(mp); 941 vfs_unbusy(mp, td); 942 if (error || (error = VFS_START(mp, 0, td)) != 0) 943 vrele(vp); 944 } else { 945 VI_LOCK(vp); 946 vp->v_iflag &= ~VI_MOUNT; 947 VI_UNLOCK(vp); 948 vfs_mount_destroy(mp, td); 949 vput(vp); 950 } 951 return (error); 952} 953 954/* 955 * Scan all active processes to see if any of them have a current 956 * or root directory of `olddp'. If so, replace them with the new 957 * mount point. 958 */ 959static void 960checkdirs(olddp, newdp) 961 struct vnode *olddp, *newdp; 962{ 963 struct filedesc *fdp; 964 struct proc *p; 965 int nrele; 966 967 if (vrefcnt(olddp) == 1) 968 return; 969 sx_slock(&allproc_lock); 970 LIST_FOREACH(p, &allproc, p_list) { 971 mtx_lock(&fdesc_mtx); 972 fdp = p->p_fd; 973 if (fdp == NULL) { 974 mtx_unlock(&fdesc_mtx); 975 continue; 976 } 977 nrele = 0; 978 FILEDESC_LOCK(fdp); 979 if (fdp->fd_cdir == olddp) { 980 VREF(newdp); 981 fdp->fd_cdir = newdp; 982 nrele++; 983 } 984 if (fdp->fd_rdir == olddp) { 985 VREF(newdp); 986 fdp->fd_rdir = newdp; 987 nrele++; 988 } 989 FILEDESC_UNLOCK(fdp); 990 mtx_unlock(&fdesc_mtx); 991 while (nrele--) 992 vrele(olddp); 993 } 994 sx_sunlock(&allproc_lock); 995 if (rootvnode == olddp) { 996 vrele(rootvnode); 997 VREF(newdp); 998 rootvnode = newdp; 999 } 1000} 1001 1002/* 1003 * Unmount a filesystem. 1004 * 1005 * Note: unmount takes a path to the vnode mounted on as argument, 1006 * not special file (as before). 1007 */ 1008#ifndef _SYS_SYSPROTO_H_ 1009struct unmount_args { 1010 char *path; 1011 int flags; 1012}; 1013#endif 1014/* ARGSUSED */ 1015int 1016unmount(td, uap) 1017 struct thread *td; 1018 register struct unmount_args /* { 1019 char *path; 1020 int flags; 1021 } */ *uap; 1022{ 1023 struct mount *mp; 1024 char *pathbuf; 1025 int error, id0, id1; 1026 1027 /* unmount(2) is not permitted inside the jail. */ 1028 if (jailed(td->td_ucred)) 1029 return (EPERM); 1030 1031 if (usermount == 0) { 1032 if ((error = suser(td)) != 0) 1033 return (error); 1034 } 1035 1036 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1037 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1038 if (error) { 1039 free(pathbuf, M_TEMP); 1040 return (error); 1041 } 1042 if (uap->flags & MNT_BYFSID) { 1043 /* Decode the filesystem ID. */ 1044 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1045 free(pathbuf, M_TEMP); 1046 return (EINVAL); 1047 } 1048 1049 mtx_lock(&mountlist_mtx); 1050 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) 1051 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1052 mp->mnt_stat.f_fsid.val[1] == id1) 1053 break; 1054 mtx_unlock(&mountlist_mtx); 1055 } else { 1056 mtx_lock(&mountlist_mtx); 1057 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) 1058 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1059 break; 1060 mtx_unlock(&mountlist_mtx); 1061 } 1062 free(pathbuf, M_TEMP); 1063 if (mp == NULL) { 1064 /* 1065 * Previously we returned ENOENT for a nonexistent path and 1066 * EINVAL for a non-mountpoint. We cannot tell these apart 1067 * now, so in the !MNT_BYFSID case return the more likely 1068 * EINVAL for compatibility. 1069 */ 1070 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1071 } 1072 1073 /* 1074 * Only root, or the user that did the original mount is 1075 * permitted to unmount this filesystem. 1076 */ 1077 if ((mp->mnt_flag & MNT_USER) != 0) { 1078 if (mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 1079 if ((error = suser(td)) != 0) 1080 return (error); 1081 } 1082 } else { 1083 if ((error = suser(td)) != 0) 1084 return (error); 1085 } 1086 1087 /* 1088 * Don't allow unmounting the root filesystem. 1089 */ 1090 if (mp->mnt_flag & MNT_ROOTFS) 1091 return (EINVAL); 1092 return (dounmount(mp, uap->flags, td)); 1093} 1094 1095/* 1096 * Do the actual filesystem unmount. 1097 */ 1098int 1099dounmount(mp, flags, td) 1100 struct mount *mp; 1101 int flags; 1102 struct thread *td; 1103{ 1104 struct vnode *coveredvp, *fsrootvp; 1105 int error; 1106 int async_flag; 1107 1108 mtx_lock(&mountlist_mtx); 1109 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1110 mtx_unlock(&mountlist_mtx); 1111 return (EBUSY); 1112 } 1113 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1114 /* Allow filesystems to detect that a forced unmount is in progress. */ 1115 if (flags & MNT_FORCE) 1116 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1117 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1118 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), &mountlist_mtx, td); 1119 if (error) { 1120 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1121 if (mp->mnt_kern_flag & MNTK_MWAIT) 1122 wakeup(mp); 1123 return (error); 1124 } 1125 vn_start_write(NULL, &mp, V_WAIT); 1126 1127 if (mp->mnt_flag & MNT_EXPUBLIC) 1128 vfs_setpublicfs(NULL, NULL, NULL); 1129 1130 vfs_msync(mp, MNT_WAIT); 1131 async_flag = mp->mnt_flag & MNT_ASYNC; 1132 mp->mnt_flag &=~ MNT_ASYNC; 1133 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1134 if (mp->mnt_syncer != NULL) 1135 vrele(mp->mnt_syncer); 1136 /* 1137 * For forced unmounts, move process cdir/rdir refs on the fs root 1138 * vnode to the covered vnode. For non-forced unmounts we want 1139 * such references to cause an EBUSY error. 1140 */ 1141 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp) == 0) { 1142 if (mp->mnt_vnodecovered != NULL) 1143 checkdirs(fsrootvp, mp->mnt_vnodecovered); 1144 if (fsrootvp == rootvnode) { 1145 vrele(rootvnode); 1146 rootvnode = NULL; 1147 } 1148 vput(fsrootvp); 1149 } 1150 if (((mp->mnt_flag & MNT_RDONLY) || 1151 (error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) == 0) || 1152 (flags & MNT_FORCE)) { 1153 error = VFS_UNMOUNT(mp, flags, td); 1154 } 1155 vn_finished_write(mp); 1156 if (error) { 1157 /* Undo cdir/rdir and rootvnode changes made above. */ 1158 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp) == 0) { 1159 if (mp->mnt_vnodecovered != NULL) 1160 checkdirs(mp->mnt_vnodecovered, fsrootvp); 1161 if (rootvnode == NULL) { 1162 rootvnode = fsrootvp; 1163 vref(rootvnode); 1164 } 1165 vput(fsrootvp); 1166 } 1167 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 1168 (void) vfs_allocate_syncvnode(mp); 1169 mtx_lock(&mountlist_mtx); 1170 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1171 mp->mnt_flag |= async_flag; 1172 lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, 1173 &mountlist_mtx, td); 1174 if (mp->mnt_kern_flag & MNTK_MWAIT) 1175 wakeup(mp); 1176 return (error); 1177 } 1178 mtx_lock(&mountlist_mtx); 1179 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1180 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 1181 coveredvp->v_mountedhere = NULL; 1182 mtx_unlock(&mountlist_mtx); 1183 vfs_mount_destroy(mp, td); 1184 if (coveredvp != NULL) 1185 vrele(coveredvp); 1186 return (0); 1187} 1188 1189/* 1190 * Lookup a filesystem type, and if found allocate and initialize 1191 * a mount structure for it. 1192 * 1193 * Devname is usually updated by mount(8) after booting. 1194 */ 1195int 1196vfs_rootmountalloc(fstypename, devname, mpp) 1197 char *fstypename; 1198 char *devname; 1199 struct mount **mpp; 1200{ 1201 struct thread *td = curthread; /* XXX */ 1202 struct vfsconf *vfsp; 1203 struct mount *mp; 1204 int error; 1205 1206 if (fstypename == NULL) 1207 return (ENODEV); 1208 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 1209 if (!strcmp(vfsp->vfc_name, fstypename)) 1210 break; 1211 if (vfsp == NULL) 1212 return (ENODEV); 1213 error = vfs_mount_alloc(NULLVP, vfsp, "/", td, &mp); 1214 if (error) 1215 return (error); 1216 mp->mnt_flag |= MNT_RDONLY | MNT_ROOTFS; 1217 strlcpy(mp->mnt_stat.f_mntfromname, devname, MNAMELEN); 1218 *mpp = mp; 1219 return (0); 1220} 1221 1222/* 1223 * Find and mount the root filesystem 1224 */ 1225void 1226vfs_mountroot(void) 1227{ 1228 char *cp; 1229 int error, i; 1230 1231 g_waitidle(); 1232 1233 /* 1234 * The root filesystem information is compiled in, and we are 1235 * booted with instructions to use it. 1236 */ 1237#ifdef ROOTDEVNAME 1238 if ((boothowto & RB_DFLTROOT) && !vfs_mountroot_try(ROOTDEVNAME)) 1239 return; 1240#endif 1241 /* 1242 * We are booted with instructions to prompt for the root filesystem, 1243 * or to use the compiled-in default when it doesn't exist. 1244 */ 1245 if (boothowto & (RB_DFLTROOT | RB_ASKNAME)) { 1246 if (!vfs_mountroot_ask()) 1247 return; 1248 } 1249 1250 /* 1251 * We've been given the generic "use CDROM as root" flag. This is 1252 * necessary because one media may be used in many different 1253 * devices, so we need to search for them. 1254 */ 1255 if (boothowto & RB_CDROM) { 1256 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1257 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1258 return; 1259 } 1260 } 1261 1262 /* 1263 * Try to use the value read by the loader from /etc/fstab, or 1264 * supplied via some other means. This is the preferred 1265 * mechanism. 1266 */ 1267 if ((cp = getenv("vfs.root.mountfrom")) != NULL) { 1268 error = vfs_mountroot_try(cp); 1269 freeenv(cp); 1270 if (!error) 1271 return; 1272 } 1273 1274 /* 1275 * Try values that may have been computed by the machine-dependant 1276 * legacy code. 1277 */ 1278 if (!vfs_mountroot_try(rootdevnames[0])) 1279 return; 1280 if (!vfs_mountroot_try(rootdevnames[1])) 1281 return; 1282 1283 /* 1284 * If we have a compiled-in default, and haven't already tried it, try 1285 * it now. 1286 */ 1287#ifdef ROOTDEVNAME 1288 if (!(boothowto & RB_DFLTROOT)) 1289 if (!vfs_mountroot_try(ROOTDEVNAME)) 1290 return; 1291#endif 1292 1293 /* 1294 * Everything so far has failed, prompt on the console if we haven't 1295 * already tried that. 1296 */ 1297 if (!(boothowto & (RB_DFLTROOT | RB_ASKNAME)) && !vfs_mountroot_ask()) 1298 return; 1299 panic("Root mount failed, startup aborted."); 1300} 1301 1302/* 1303 * Mount (mountfrom) as the root filesystem. 1304 */ 1305static int 1306vfs_mountroot_try(char *mountfrom) 1307{ 1308 struct mount *mp; 1309 char *vfsname, *path; 1310 const char *devname; 1311 int error; 1312 char patt[32]; 1313 int s; 1314 1315 vfsname = NULL; 1316 path = NULL; 1317 mp = NULL; 1318 error = EINVAL; 1319 1320 if (mountfrom == NULL) 1321 return(error); /* don't complain */ 1322 1323 s = splcam(); /* Overkill, but annoying without it */ 1324 printf("Mounting root from %s\n", mountfrom); 1325 splx(s); 1326 1327 /* parse vfs name and path */ 1328 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1329 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1330 vfsname[0] = path[0] = 0; 1331 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1332 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1333 goto done; 1334 1335 /* allocate a root mount */ 1336 error = vfs_rootmountalloc(vfsname, path[0] != 0 ? path : ROOTNAME, 1337 &mp); 1338 if (error != 0) { 1339 printf("Can't allocate root mount for filesystem '%s': %d\n", 1340 vfsname, error); 1341 goto done; 1342 } 1343 1344 /* do our best to set rootdev */ 1345 if ((path[0] != 0) && setrootbyname(path)) 1346 printf("setrootbyname failed\n"); 1347 1348 /* If the root device is a type "memory disk", mount RW */ 1349 if (rootdev != NODEV && devsw(rootdev) != NULL) { 1350 devname = devtoname(rootdev); 1351 if (devname[0] == 'm' && devname[1] == 'd') 1352 mp->mnt_flag &= ~MNT_RDONLY; 1353 } 1354 1355 error = VFS_MOUNT(mp, NULL, NULL, NULL, curthread); 1356 1357done: 1358 if (vfsname != NULL) 1359 free(vfsname, M_MOUNT); 1360 if (path != NULL) 1361 free(path, M_MOUNT); 1362 if (error != 0) { 1363 if (mp != NULL) 1364 vfs_mount_destroy(mp, curthread); 1365 printf("Root mount failed: %d\n", error); 1366 } else { 1367 1368 /* register with list of mounted filesystems */ 1369 mtx_lock(&mountlist_mtx); 1370 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1371 mtx_unlock(&mountlist_mtx); 1372 1373 /* sanity check system clock against root fs timestamp */ 1374 inittodr(mp->mnt_time); 1375 vfs_unbusy(mp, curthread); 1376 error = VFS_START(mp, 0, curthread); 1377 } 1378 return(error); 1379} 1380 1381/* 1382 * Spin prompting on the console for a suitable root filesystem 1383 */ 1384static int 1385vfs_mountroot_ask(void) 1386{ 1387 char name[128]; 1388 1389 for(;;) { 1390 printf("\nManual root filesystem specification:\n"); 1391 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1392#if defined(__i386__) || defined(__ia64__) 1393 printf(" eg. ufs:da0s1a\n"); 1394#else 1395 printf(" eg. ufs:/dev/da0a\n"); 1396#endif 1397 printf(" ? List valid disk boot devices\n"); 1398 printf(" <empty line> Abort manual input\n"); 1399 printf("\nmountroot> "); 1400 gets(name); 1401 if (name[0] == 0) 1402 return(1); 1403 if (name[0] == '?') { 1404 printf("\nList of GEOM managed disk devices:\n "); 1405 g_dev_print(); 1406 continue; 1407 } 1408 if (!vfs_mountroot_try(name)) 1409 return(0); 1410 } 1411} 1412 1413/* 1414 * Local helper function for vfs_mountroot_ask. 1415 */ 1416static void 1417gets(char *cp) 1418{ 1419 char *lp; 1420 int c; 1421 1422 lp = cp; 1423 for (;;) { 1424 printf("%c", c = cngetc() & 0177); 1425 switch (c) { 1426 case -1: 1427 case '\n': 1428 case '\r': 1429 *lp++ = '\0'; 1430 return; 1431 case '\b': 1432 case '\177': 1433 if (lp > cp) { 1434 printf(" \b"); 1435 lp--; 1436 } 1437 continue; 1438 case '#': 1439 lp--; 1440 if (lp < cp) 1441 lp = cp; 1442 continue; 1443 case '@': 1444 case 'u' & 037: 1445 lp = cp; 1446 printf("%c", '\n'); 1447 continue; 1448 default: 1449 *lp++ = c; 1450 } 1451 } 1452} 1453 1454/* 1455 * Convert a given name to the dev_t of the disk-like device 1456 * it refers to. 1457 */ 1458dev_t 1459getdiskbyname(char *name) { 1460 char *cp; 1461 dev_t dev; 1462 1463 cp = name; 1464 if (!bcmp(cp, "/dev/", 5)) 1465 cp += 5; 1466 1467 dev = NODEV; 1468 EVENTHANDLER_INVOKE(dev_clone, cp, strlen(cp), &dev); 1469 return (dev); 1470} 1471 1472/* 1473 * Set rootdev to match (name), given that we expect it to 1474 * refer to a disk-like device. 1475 */ 1476static int 1477setrootbyname(char *name) 1478{ 1479 dev_t diskdev; 1480 1481 diskdev = getdiskbyname(name); 1482 if (diskdev != NODEV) { 1483 rootdev = diskdev; 1484 return (0); 1485 } 1486 1487 return (1); 1488} 1489 1490/* Show the dev_t for a disk specified by name */ 1491#ifdef DDB 1492DB_SHOW_COMMAND(disk, db_getdiskbyname) 1493{ 1494 dev_t dev; 1495 1496 if (modif[0] == '\0') { 1497 db_error("usage: show disk/devicename"); 1498 return; 1499 } 1500 dev = getdiskbyname(modif); 1501 if (dev != NODEV) 1502 db_printf("dev_t = %p\n", dev); 1503 else 1504 db_printf("No disk device matched.\n"); 1505} 1506#endif 1507 1508/* 1509 * Get a mount option by its name. 1510 * 1511 * Return 0 if the option was found, ENOENT otherwise. 1512 * If len is non-NULL it will be filled with the length 1513 * of the option. If buf is non-NULL, it will be filled 1514 * with the address of the option. 1515 */ 1516int 1517vfs_getopt(opts, name, buf, len) 1518 struct vfsoptlist *opts; 1519 const char *name; 1520 void **buf; 1521 int *len; 1522{ 1523 struct vfsopt *opt; 1524 1525 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1526 1527 TAILQ_FOREACH(opt, opts, link) { 1528 if (strcmp(name, opt->name) == 0) { 1529 if (len != NULL) 1530 *len = opt->len; 1531 if (buf != NULL) 1532 *buf = opt->value; 1533 return (0); 1534 } 1535 } 1536 return (ENOENT); 1537} 1538 1539/* 1540 * Find and copy a mount option. 1541 * 1542 * The size of the buffer has to be specified 1543 * in len, if it is not the same length as the 1544 * mount option, EINVAL is returned. 1545 * Returns ENOENT if the option is not found. 1546 */ 1547int 1548vfs_copyopt(opts, name, dest, len) 1549 struct vfsoptlist *opts; 1550 const char *name; 1551 void *dest; 1552 int len; 1553{ 1554 struct vfsopt *opt; 1555 1556 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1557 1558 TAILQ_FOREACH(opt, opts, link) { 1559 if (strcmp(name, opt->name) == 0) { 1560 if (len != opt->len) 1561 return (EINVAL); 1562 bcopy(opt->value, dest, opt->len); 1563 return (0); 1564 } 1565 } 1566 return (ENOENT); 1567} 1568