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 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * Copyright (c) 1999 Michael Smith 35 * All rights reserved. 36 * Copyright (c) 1999 Poul-Henning Kamp 37 * All rights reserved. 38 * 39 * Redistribution and use in source and binary forms, with or without 40 * modification, are permitted provided that the following conditions 41 * are met: 42 * 1. Redistributions of source code must retain the above copyright 43 * notice, this list of conditions and the following disclaimer. 44 * 2. Redistributions in binary form must reproduce the above copyright 45 * notice, this list of conditions and the following disclaimer in the 46 * documentation and/or other materials provided with the distribution. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 */ 60 61 #include <sys/cdefs.h> 62 __FBSDID("$FreeBSD$"); 63 64 #include <sys/param.h> 65 #include <sys/conf.h> 66 #include <sys/cons.h> 67 #include <sys/jail.h> 68 #include <sys/kernel.h> 69 #include <sys/linker.h> 70 #include <sys/mac.h> 71 #include <sys/malloc.h> 72 #include <sys/mount.h> 73 #include <sys/mutex.h> 74 #include <sys/namei.h> 75 #include <sys/proc.h> 76 #include <sys/filedesc.h> 77 #include <sys/reboot.h> 78 #include <sys/sysproto.h> 79 #include <sys/sx.h> 80 #include <sys/sysctl.h> 81 #include <sys/sysent.h> 82 #include <sys/systm.h> 83 #include <sys/vnode.h> 84 85 #include <geom/geom.h> 86 87 #include <machine/stdarg.h> 88 89 #include "opt_rootdevname.h" 90 #include "opt_ddb.h" 91 #include "opt_mac.h" 92 93 #ifdef DDB 94 #include <ddb/ddb.h> 95 #endif 96 97 #define ROOTNAME "root_device" 98 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 99 100 static void checkdirs(struct vnode *olddp, struct vnode *newdp); 101 static void gets(char *cp); 102 static int vfs_domount(struct thread *td, const char *fstype, 103 char *fspath, int fsflags, void *fsdata, int compat); 104 static int vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 105 const char *fspath, struct thread *td, struct mount **mpp); 106 static int vfs_mountroot_ask(void); 107 static int vfs_mountroot_try(char *mountfrom); 108 109 static int usermount = 0; 110 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 111 "Unprivileged users may mount and unmount file systems"); 112 113 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 114 115 /* List of mounted filesystems. */ 116 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 117 118 /* For any iteration/modification of mountlist */ 119 struct mtx mountlist_mtx; 120 121 /* 122 * The vnode of the system's root (/ in the filesystem, without chroot 123 * active.) 124 */ 125 struct vnode *rootvnode; 126 127 /* 128 * The root filesystem is detailed in the kernel environment variable 129 * vfs.root.mountfrom, which is expected to be in the general format 130 * 131 * <vfsname>:[<path>] 132 * vfsname := the name of a VFS known to the kernel and capable 133 * of being mounted as root 134 * path := disk device name or other data used by the filesystem 135 * to locate its physical store 136 */ 137 138 /* 139 * The root specifiers we will try if RB_CDROM is specified. 140 */ 141 static char *cdrom_rootdevnames[] = { 142 "cd9660:cd0", 143 "cd9660:acd0", 144 NULL 145 }; 146 147 /* legacy find-root code */ 148 char *rootdevnames[2] = {NULL, NULL}; 149 static int setrootbyname(char *name); 150 struct cdev *rootdev = NULL; 151 152 /* 153 * Has to be dynamic as the value of rootdev can change; however, it can't 154 * change after the root is mounted, so a user process can't access this 155 * sysctl until after the value is unchangeable. 156 */ 157 static int 158 sysctl_rootdev(SYSCTL_HANDLER_ARGS) 159 { 160 int error; 161 162 /* _RD prevents this from happening. */ 163 KASSERT(req->newptr == NULL, ("Attempt to change root device name")); 164 165 if (rootdev != NULL) 166 error = sysctl_handle_string(oidp, rootdev->si_name, 0, req); 167 else 168 error = sysctl_handle_string(oidp, "", 0, req); 169 170 return (error); 171 } 172 173 SYSCTL_PROC(_kern, OID_AUTO, rootdev, CTLTYPE_STRING | CTLFLAG_RD, 174 0, 0, sysctl_rootdev, "A", "Root file system device"); 175 176 /* Remove one mount option. */ 177 static void 178 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 179 { 180 181 TAILQ_REMOVE(opts, opt, link); 182 free(opt->name, M_MOUNT); 183 if (opt->value != NULL) 184 free(opt->value, M_MOUNT); 185 #ifdef INVARIANTS 186 else if (opt->len != 0) 187 panic("%s: mount option with NULL value but length != 0", 188 __func__); 189 #endif 190 free(opt, M_MOUNT); 191 } 192 193 /* Release all resources related to the mount options. */ 194 static void 195 vfs_freeopts(struct vfsoptlist *opts) 196 { 197 struct vfsopt *opt; 198 199 while (!TAILQ_EMPTY(opts)) { 200 opt = TAILQ_FIRST(opts); 201 vfs_freeopt(opts, opt); 202 } 203 free(opts, M_MOUNT); 204 } 205 206 /* 207 * Check if options are equal (with or without the "no" prefix). 208 */ 209 static int 210 vfs_equalopts(const char *opt1, const char *opt2) 211 { 212 213 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 214 if (strcmp(opt1, opt2) == 0) 215 return (1); 216 /* "noopt" vs. "opt" */ 217 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 218 return (1); 219 /* "opt" vs. "noopt" */ 220 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 221 return (1); 222 return (0); 223 } 224 225 /* 226 * If a mount option is specified several times, 227 * (with or without the "no" prefix) only keep 228 * the last occurence of it. 229 */ 230 static void 231 vfs_sanitizeopts(struct vfsoptlist *opts) 232 { 233 struct vfsopt *opt, *opt2, *tmp; 234 235 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 236 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 237 while (opt2 != NULL) { 238 if (vfs_equalopts(opt->name, opt2->name)) { 239 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 240 vfs_freeopt(opts, opt2); 241 opt2 = tmp; 242 } else { 243 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 244 } 245 } 246 } 247 } 248 249 /* 250 * Build a linked list of mount options from a struct uio. 251 */ 252 static int 253 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 254 { 255 struct vfsoptlist *opts; 256 struct vfsopt *opt; 257 size_t memused; 258 unsigned int i, iovcnt; 259 int error, namelen, optlen; 260 261 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 262 TAILQ_INIT(opts); 263 memused = 0; 264 iovcnt = auio->uio_iovcnt; 265 for (i = 0; i < iovcnt; i += 2) { 266 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 267 namelen = auio->uio_iov[i].iov_len; 268 optlen = auio->uio_iov[i + 1].iov_len; 269 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 270 opt->value = NULL; 271 opt->len = optlen; 272 273 /* 274 * Do this early, so jumps to "bad" will free the current 275 * option. 276 */ 277 TAILQ_INSERT_TAIL(opts, opt, link); 278 memused += sizeof(struct vfsopt) + optlen + namelen; 279 280 /* 281 * Avoid consuming too much memory, and attempts to overflow 282 * memused. 283 */ 284 if (memused > VFS_MOUNTARG_SIZE_MAX || 285 optlen > VFS_MOUNTARG_SIZE_MAX || 286 namelen > VFS_MOUNTARG_SIZE_MAX) { 287 error = EINVAL; 288 goto bad; 289 } 290 291 if (auio->uio_segflg == UIO_SYSSPACE) { 292 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 293 } else { 294 error = copyin(auio->uio_iov[i].iov_base, opt->name, 295 namelen); 296 if (error) 297 goto bad; 298 } 299 /* Ensure names are null-terminated strings. */ 300 if (opt->name[namelen - 1] != '\0') { 301 error = EINVAL; 302 goto bad; 303 } 304 if (optlen != 0) { 305 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 306 if (auio->uio_segflg == UIO_SYSSPACE) { 307 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 308 optlen); 309 } else { 310 error = copyin(auio->uio_iov[i + 1].iov_base, 311 opt->value, optlen); 312 if (error) 313 goto bad; 314 } 315 } 316 } 317 vfs_sanitizeopts(opts); 318 *options = opts; 319 return (0); 320 bad: 321 vfs_freeopts(opts); 322 return (error); 323 } 324 325 /* 326 * Merge the old mount options with the new ones passed 327 * in the MNT_UPDATE case. 328 */ 329 static void 330 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 331 { 332 struct vfsopt *opt, *opt2, *new; 333 334 TAILQ_FOREACH(opt, opts, link) { 335 /* 336 * Check that this option hasn't been redefined 337 * nor cancelled with a "no" mount option. 338 */ 339 opt2 = TAILQ_FIRST(toopts); 340 while (opt2 != NULL) { 341 if (strcmp(opt2->name, opt->name) == 0) 342 goto next; 343 if (strncmp(opt2->name, "no", 2) == 0 && 344 strcmp(opt2->name + 2, opt->name) == 0) { 345 vfs_freeopt(toopts, opt2); 346 goto next; 347 } 348 opt2 = TAILQ_NEXT(opt2, link); 349 } 350 /* We want this option, duplicate it. */ 351 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 352 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 353 strcpy(new->name, opt->name); 354 if (opt->len != 0) { 355 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 356 bcopy(opt->value, new->value, opt->len); 357 } else { 358 new->value = NULL; 359 } 360 new->len = opt->len; 361 TAILQ_INSERT_TAIL(toopts, new, link); 362 next: 363 continue; 364 } 365 } 366 367 /* 368 * New mount API. 369 */ 370 int 371 nmount(td, uap) 372 struct thread *td; 373 struct nmount_args /* { 374 struct iovec *iovp; 375 unsigned int iovcnt; 376 int flags; 377 } */ *uap; 378 { 379 struct uio auio; 380 struct iovec *iov, *needfree; 381 struct iovec aiov[UIO_SMALLIOV]; 382 unsigned int i; 383 int error; 384 u_int iovlen, iovcnt; 385 386 iovcnt = uap->iovcnt; 387 iovlen = iovcnt * sizeof (struct iovec); 388 /* 389 * Check that we have an even number of iovec's 390 * and that we have at least two options. 391 */ 392 if ((iovcnt & 1) || (iovcnt < 4) || (iovcnt > UIO_MAXIOV)) 393 return (EINVAL); 394 395 if (iovcnt > UIO_SMALLIOV) { 396 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); 397 needfree = iov; 398 } else { 399 iov = aiov; 400 needfree = NULL; 401 } 402 auio.uio_iov = iov; 403 auio.uio_iovcnt = iovcnt; 404 auio.uio_segflg = UIO_USERSPACE; 405 if ((error = copyin(uap->iovp, iov, iovlen))) 406 goto finish; 407 408 for (i = 0; i < iovcnt; i++) { 409 if (iov->iov_len > MMAXOPTIONLEN) { 410 error = EINVAL; 411 goto finish; 412 } 413 iov++; 414 } 415 error = vfs_nmount(td, uap->flags, &auio); 416 finish: 417 if (needfree != NULL) 418 free(needfree, M_TEMP); 419 return (error); 420 } 421 422 int 423 kernel_mount(iovp, iovcnt, flags) 424 struct iovec *iovp; 425 unsigned int iovcnt; 426 int flags; 427 { 428 struct uio auio; 429 int error; 430 431 /* 432 * Check that we have an even number of iovec's 433 * and that we have at least two options. 434 */ 435 if ((iovcnt & 1) || (iovcnt < 4)) 436 return (EINVAL); 437 438 auio.uio_iov = iovp; 439 auio.uio_iovcnt = iovcnt; 440 auio.uio_segflg = UIO_SYSSPACE; 441 442 error = vfs_nmount(curthread, flags, &auio); 443 return (error); 444 } 445 446 int 447 kernel_vmount(int flags, ...) 448 { 449 struct iovec *iovp; 450 struct uio auio; 451 va_list ap; 452 unsigned int iovcnt, iovlen, len; 453 const char *cp; 454 char *buf, *pos; 455 size_t n; 456 int error, i; 457 458 len = 0; 459 va_start(ap, flags); 460 for (iovcnt = 0; (cp = va_arg(ap, const char *)) != NULL; iovcnt++) 461 len += strlen(cp) + 1; 462 va_end(ap); 463 464 if (iovcnt < 4 || iovcnt & 1) 465 return (EINVAL); 466 467 iovlen = iovcnt * sizeof (struct iovec); 468 MALLOC(iovp, struct iovec *, iovlen, M_MOUNT, M_WAITOK); 469 MALLOC(buf, char *, len, M_MOUNT, M_WAITOK); 470 pos = buf; 471 va_start(ap, flags); 472 for (i = 0; i < iovcnt; i++) { 473 cp = va_arg(ap, const char *); 474 copystr(cp, pos, len - (pos - buf), &n); 475 iovp[i].iov_base = pos; 476 iovp[i].iov_len = n; 477 pos += n; 478 } 479 va_end(ap); 480 481 auio.uio_iov = iovp; 482 auio.uio_iovcnt = iovcnt; 483 auio.uio_segflg = UIO_SYSSPACE; 484 485 error = vfs_nmount(curthread, flags, &auio); 486 FREE(iovp, M_MOUNT); 487 FREE(buf, M_MOUNT); 488 return (error); 489 } 490 491 /* 492 * Allocate and initialize the mount point struct. 493 */ 494 static int 495 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 496 const char *fspath, struct thread *td, struct mount **mpp) 497 { 498 struct mount *mp; 499 500 mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 501 TAILQ_INIT(&mp->mnt_nvnodelist); 502 mp->mnt_nvnodelistsize = 0; 503 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 504 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 505 vfs_busy(mp, LK_NOWAIT, 0, td); 506 mp->mnt_op = vfsp->vfc_vfsops; 507 mp->mnt_vfc = vfsp; 508 vfsp->vfc_refcount++; 509 mp->mnt_stat.f_type = vfsp->vfc_typenum; 510 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 511 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 512 mp->mnt_vnodecovered = vp; 513 mp->mnt_cred = crdup(td->td_ucred); 514 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 515 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 516 mp->mnt_iosize_max = DFLTPHYS; 517 #ifdef MAC 518 mac_init_mount(mp); 519 mac_create_mount(td->td_ucred, mp); 520 #endif 521 *mpp = mp; 522 return (0); 523 } 524 525 /* 526 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 527 */ 528 void 529 vfs_mount_destroy(struct mount *mp, struct thread *td) 530 { 531 532 mp->mnt_vfc->vfc_refcount--; 533 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 534 panic("unmount: dangling vnode"); 535 vfs_unbusy(mp,td); 536 lockdestroy(&mp->mnt_lock); 537 mtx_destroy(&mp->mnt_mtx); 538 if (mp->mnt_kern_flag & MNTK_MWAIT) 539 wakeup(mp); 540 #ifdef MAC 541 mac_destroy_mount(mp); 542 #endif 543 if (mp->mnt_opt != NULL) 544 vfs_freeopts(mp->mnt_opt); 545 crfree(mp->mnt_cred); 546 free(mp, M_MOUNT); 547 } 548 549 int 550 vfs_nmount(struct thread *td, int fsflags, struct uio *fsoptions) 551 { 552 struct vfsoptlist *optlist; 553 char *fstype, *fspath; 554 int error, fstypelen, fspathlen; 555 556 error = vfs_buildopts(fsoptions, &optlist); 557 if (error) 558 return (error); 559 560 /* 561 * We need these two options before the others, 562 * and they are mandatory for any filesystem. 563 * Ensure they are NUL terminated as well. 564 */ 565 fstypelen = 0; 566 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 567 if (error || fstype[fstypelen - 1] != '\0') { 568 error = EINVAL; 569 goto bail; 570 } 571 fspathlen = 0; 572 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 573 if (error || fspath[fspathlen - 1] != '\0') { 574 error = EINVAL; 575 goto bail; 576 } 577 578 /* 579 * Be ultra-paranoid about making sure the type and fspath 580 * variables will fit in our mp buffers, including the 581 * terminating NUL. 582 */ 583 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 584 error = ENAMETOOLONG; 585 goto bail; 586 } 587 588 error = vfs_domount(td, fstype, fspath, fsflags, optlist, 0); 589 bail: 590 if (error) 591 vfs_freeopts(optlist); 592 return (error); 593 } 594 595 /* 596 * Old mount API. 597 */ 598 #ifndef _SYS_SYSPROTO_H_ 599 struct mount_args { 600 char *type; 601 char *path; 602 int flags; 603 caddr_t data; 604 }; 605 #endif 606 /* ARGSUSED */ 607 int 608 mount(td, uap) 609 struct thread *td; 610 struct mount_args /* { 611 char *type; 612 char *path; 613 int flags; 614 caddr_t data; 615 } */ *uap; 616 { 617 char *fstype; 618 char *fspath; 619 int error; 620 621 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 622 fspath = malloc(MNAMELEN, M_TEMP, M_WAITOK); 623 624 /* 625 * vfs_mount() actually takes a kernel string for `type' and 626 * `path' now, so extract them. 627 */ 628 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 629 if (error == 0) 630 error = copyinstr(uap->path, fspath, MNAMELEN, NULL); 631 if (error == 0) 632 error = vfs_domount(td, fstype, fspath, uap->flags, 633 uap->data, 1); 634 free(fstype, M_TEMP); 635 free(fspath, M_TEMP); 636 return (error); 637 } 638 639 /* 640 * vfs_mount(): actually attempt a filesystem mount. 641 * 642 * This routine is designed to be a "generic" entry point for routines 643 * that wish to mount a filesystem. All parameters except `fsdata' are 644 * pointers into kernel space. `fsdata' is currently still a pointer 645 * into userspace. 646 */ 647 int 648 vfs_mount(td, fstype, fspath, fsflags, fsdata) 649 struct thread *td; 650 const char *fstype; 651 char *fspath; 652 int fsflags; 653 void *fsdata; 654 { 655 656 return (vfs_domount(td, fstype, fspath, fsflags, fsdata, 1)); 657 } 658 659 /* 660 * vfs_domount(): actually attempt a filesystem mount. 661 */ 662 static int 663 vfs_domount( 664 struct thread *td, /* Flags common to all filesystems. */ 665 const char *fstype, /* Filesystem type. */ 666 char *fspath, /* Mount path. */ 667 int fsflags, /* Flags common to all filesystems. */ 668 void *fsdata, /* Options local to the filesystem. */ 669 int compat /* Invocation from compat syscall. */ 670 ) 671 { 672 linker_file_t lf; 673 struct vnode *vp; 674 struct mount *mp; 675 struct vfsconf *vfsp; 676 int error, flag = 0, kern_flag = 0; 677 struct vattr va; 678 struct nameidata nd; 679 680 /* 681 * Be ultra-paranoid about making sure the type and fspath 682 * variables will fit in our mp buffers, including the 683 * terminating NUL. 684 */ 685 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 686 return (ENAMETOOLONG); 687 688 if (jailed(td->td_ucred)) 689 return (EPERM); 690 if (usermount == 0) { 691 if ((error = suser(td)) != 0) 692 return (error); 693 } 694 695 /* 696 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 697 */ 698 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 699 if ((error = suser(td)) != 0) 700 return (error); 701 } 702 /* 703 * Silently enforce MNT_NODEV, MNT_NOSUID and MNT_USER for 704 * unprivileged users. 705 */ 706 if (suser(td) != 0) 707 fsflags |= MNT_NODEV | MNT_NOSUID | MNT_USER; 708 /* 709 * Get vnode to be covered 710 */ 711 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 712 if ((error = namei(&nd)) != 0) 713 return (error); 714 NDFREE(&nd, NDF_ONLY_PNBUF); 715 vp = nd.ni_vp; 716 if (fsflags & MNT_UPDATE) { 717 if ((vp->v_vflag & VV_ROOT) == 0) { 718 vput(vp); 719 return (EINVAL); 720 } 721 mp = vp->v_mount; 722 flag = mp->mnt_flag; 723 kern_flag = mp->mnt_kern_flag; 724 /* 725 * We only allow the filesystem to be reloaded if it 726 * is currently mounted read-only. 727 */ 728 if ((fsflags & MNT_RELOAD) && 729 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 730 vput(vp); 731 return (EOPNOTSUPP); /* Needs translation */ 732 } 733 /* 734 * Only privileged root, or (if MNT_USER is set) the user that 735 * did the original mount is permitted to update it. 736 */ 737 if ((mp->mnt_flag & MNT_USER) == 0 || 738 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 739 if ((error = suser(td)) != 0) { 740 vput(vp); 741 return (error); 742 } 743 } 744 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 745 vput(vp); 746 return (EBUSY); 747 } 748 VI_LOCK(vp); 749 if ((vp->v_iflag & VI_MOUNT) != 0 || 750 vp->v_mountedhere != NULL) { 751 VI_UNLOCK(vp); 752 vfs_unbusy(mp, td); 753 vput(vp); 754 return (EBUSY); 755 } 756 vp->v_iflag |= VI_MOUNT; 757 VI_UNLOCK(vp); 758 mp->mnt_flag |= fsflags & 759 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT); 760 VOP_UNLOCK(vp, 0, td); 761 if (compat == 0) { 762 mp->mnt_optnew = fsdata; 763 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 764 } 765 goto update; 766 } 767 /* 768 * If the user is not root, ensure that they own the directory 769 * onto which we are attempting to mount. 770 */ 771 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 772 if (error) { 773 vput(vp); 774 return (error); 775 } 776 if (va.va_uid != td->td_ucred->cr_uid) { 777 if ((error = suser(td)) != 0) { 778 vput(vp); 779 return (error); 780 } 781 } 782 if ((error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0)) != 0) { 783 vput(vp); 784 return (error); 785 } 786 if (vp->v_type != VDIR) { 787 vput(vp); 788 return (ENOTDIR); 789 } 790 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 791 if (strcmp(vfsp->vfc_name, fstype) == 0) 792 break; 793 if (vfsp == NULL) { 794 /* Only load modules for root (very important!). */ 795 if ((error = suser(td)) != 0) { 796 vput(vp); 797 return (error); 798 } 799 error = securelevel_gt(td->td_ucred, 0); 800 if (error) { 801 vput(vp); 802 return (error); 803 } 804 error = linker_load_module(NULL, fstype, NULL, NULL, &lf); 805 if (error || lf == NULL) { 806 vput(vp); 807 if (lf == NULL) 808 error = ENODEV; 809 return (error); 810 } 811 lf->userrefs++; 812 /* Look up again to see if the VFS was loaded. */ 813 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 814 if (strcmp(vfsp->vfc_name, fstype) == 0) 815 break; 816 if (vfsp == NULL) { 817 lf->userrefs--; 818 linker_file_unload(lf); 819 vput(vp); 820 return (ENODEV); 821 } 822 } 823 VI_LOCK(vp); 824 if ((vp->v_iflag & VI_MOUNT) != 0 || 825 vp->v_mountedhere != NULL) { 826 VI_UNLOCK(vp); 827 vput(vp); 828 return (EBUSY); 829 } 830 vp->v_iflag |= VI_MOUNT; 831 VI_UNLOCK(vp); 832 833 /* 834 * Allocate and initialize the filesystem. 835 */ 836 error = vfs_mount_alloc(vp, vfsp, fspath, td, &mp); 837 if (error) { 838 vput(vp); 839 return (error); 840 } 841 VOP_UNLOCK(vp, 0, td); 842 843 /* XXXMAC: pass to vfs_mount_alloc? */ 844 if (compat == 0) 845 mp->mnt_optnew = fsdata; 846 update: 847 /* 848 * Check if the fs implements the type VFS_[N]MOUNT() 849 * function we are looking for. 850 */ 851 if ((compat == 0) == (mp->mnt_op->vfs_mount != NULL)) { 852 printf("%s doesn't support the %s mount syscall\n", 853 mp->mnt_vfc->vfc_name, compat ? "old" : "new"); 854 VI_LOCK(vp); 855 vp->v_iflag &= ~VI_MOUNT; 856 VI_UNLOCK(vp); 857 if (mp->mnt_flag & MNT_UPDATE) 858 vfs_unbusy(mp, td); 859 else 860 vfs_mount_destroy(mp, td); 861 vrele(vp); 862 return (EOPNOTSUPP); 863 } 864 865 /* 866 * Set the mount level flags. 867 */ 868 if (fsflags & MNT_RDONLY) 869 mp->mnt_flag |= MNT_RDONLY; 870 else if (mp->mnt_flag & MNT_RDONLY) 871 mp->mnt_kern_flag |= MNTK_WANTRDWR; 872 mp->mnt_flag &=~ MNT_UPDATEMASK; 873 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE); 874 /* 875 * Mount the filesystem. 876 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 877 * get. No freeing of cn_pnbuf. 878 */ 879 error = compat ? VFS_MOUNT(mp, fspath, fsdata, &nd, td) : 880 VFS_NMOUNT(mp, &nd, td); 881 if (!error) { 882 if (mp->mnt_opt != NULL) 883 vfs_freeopts(mp->mnt_opt); 884 mp->mnt_opt = mp->mnt_optnew; 885 } 886 /* 887 * Prevent external consumers of mount options from reading 888 * mnt_optnew. 889 */ 890 mp->mnt_optnew = NULL; 891 if (mp->mnt_flag & MNT_UPDATE) { 892 if (mp->mnt_kern_flag & MNTK_WANTRDWR) 893 mp->mnt_flag &= ~MNT_RDONLY; 894 mp->mnt_flag &= 895 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 896 mp->mnt_kern_flag &= ~MNTK_WANTRDWR; 897 if (error) { 898 mp->mnt_flag = flag; 899 mp->mnt_kern_flag = kern_flag; 900 } 901 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 902 if (mp->mnt_syncer == NULL) 903 error = vfs_allocate_syncvnode(mp); 904 } else { 905 if (mp->mnt_syncer != NULL) 906 vrele(mp->mnt_syncer); 907 mp->mnt_syncer = NULL; 908 } 909 vfs_unbusy(mp, td); 910 VI_LOCK(vp); 911 vp->v_iflag &= ~VI_MOUNT; 912 VI_UNLOCK(vp); 913 vrele(vp); 914 return (error); 915 } 916 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 917 /* 918 * Put the new filesystem on the mount list after root. 919 */ 920 cache_purge(vp); 921 if (!error) { 922 struct vnode *newdp; 923 924 VI_LOCK(vp); 925 vp->v_iflag &= ~VI_MOUNT; 926 VI_UNLOCK(vp); 927 vp->v_mountedhere = mp; 928 mtx_lock(&mountlist_mtx); 929 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 930 mtx_unlock(&mountlist_mtx); 931 if (VFS_ROOT(mp, &newdp)) 932 panic("mount: lost mount"); 933 checkdirs(vp, newdp); 934 vput(newdp); 935 VOP_UNLOCK(vp, 0, td); 936 if ((mp->mnt_flag & MNT_RDONLY) == 0) 937 error = vfs_allocate_syncvnode(mp); 938 vfs_unbusy(mp, td); 939 if (error || (error = VFS_START(mp, 0, td)) != 0) 940 vrele(vp); 941 } else { 942 VI_LOCK(vp); 943 vp->v_iflag &= ~VI_MOUNT; 944 VI_UNLOCK(vp); 945 vfs_mount_destroy(mp, td); 946 vput(vp); 947 } 948 return (error); 949 } 950 951 /* 952 * Scan all active processes to see if any of them have a current 953 * or root directory of `olddp'. If so, replace them with the new 954 * mount point. 955 */ 956 static void 957 checkdirs(olddp, newdp) 958 struct vnode *olddp, *newdp; 959 { 960 struct filedesc *fdp; 961 struct proc *p; 962 int nrele; 963 964 if (vrefcnt(olddp) == 1) 965 return; 966 sx_slock(&allproc_lock); 967 LIST_FOREACH(p, &allproc, p_list) { 968 mtx_lock(&fdesc_mtx); 969 fdp = p->p_fd; 970 if (fdp == NULL) { 971 mtx_unlock(&fdesc_mtx); 972 continue; 973 } 974 nrele = 0; 975 FILEDESC_LOCK(fdp); 976 if (fdp->fd_cdir == olddp) { 977 VREF(newdp); 978 fdp->fd_cdir = newdp; 979 nrele++; 980 } 981 if (fdp->fd_rdir == olddp) { 982 VREF(newdp); 983 fdp->fd_rdir = newdp; 984 nrele++; 985 } 986 FILEDESC_UNLOCK(fdp); 987 mtx_unlock(&fdesc_mtx); 988 while (nrele--) 989 vrele(olddp); 990 } 991 sx_sunlock(&allproc_lock); 992 if (rootvnode == olddp) { 993 vrele(rootvnode); 994 VREF(newdp); 995 rootvnode = newdp; 996 } 997 } 998 999 /* 1000 * Unmount a filesystem. 1001 * 1002 * Note: unmount takes a path to the vnode mounted on as argument, 1003 * not special file (as before). 1004 */ 1005 #ifndef _SYS_SYSPROTO_H_ 1006 struct unmount_args { 1007 char *path; 1008 int flags; 1009 }; 1010 #endif 1011 /* ARGSUSED */ 1012 int 1013 unmount(td, uap) 1014 struct thread *td; 1015 register struct unmount_args /* { 1016 char *path; 1017 int flags; 1018 } */ *uap; 1019 { 1020 struct mount *mp; 1021 char *pathbuf; 1022 int error, id0, id1; 1023 1024 if (jailed(td->td_ucred)) 1025 return (EPERM); 1026 if (usermount == 0) { 1027 if ((error = suser(td)) != 0) 1028 return (error); 1029 } 1030 1031 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1032 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1033 if (error) { 1034 free(pathbuf, M_TEMP); 1035 return (error); 1036 } 1037 if (uap->flags & MNT_BYFSID) { 1038 /* Decode the filesystem ID. */ 1039 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1040 free(pathbuf, M_TEMP); 1041 return (EINVAL); 1042 } 1043 1044 mtx_lock(&mountlist_mtx); 1045 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1046 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1047 mp->mnt_stat.f_fsid.val[1] == id1) 1048 break; 1049 } 1050 mtx_unlock(&mountlist_mtx); 1051 } else { 1052 mtx_lock(&mountlist_mtx); 1053 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1054 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1055 break; 1056 } 1057 mtx_unlock(&mountlist_mtx); 1058 } 1059 free(pathbuf, M_TEMP); 1060 if (mp == NULL) { 1061 /* 1062 * Previously we returned ENOENT for a nonexistent path and 1063 * EINVAL for a non-mountpoint. We cannot tell these apart 1064 * now, so in the !MNT_BYFSID case return the more likely 1065 * EINVAL for compatibility. 1066 */ 1067 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1068 } 1069 1070 /* 1071 * Only privileged root, or (if MNT_USER is set) the user that did the 1072 * original mount is permitted to unmount this filesystem. 1073 */ 1074 if ((mp->mnt_flag & MNT_USER) == 0 || 1075 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 1076 if ((error = suser(td)) != 0) 1077 return (error); 1078 } 1079 1080 /* 1081 * Don't allow unmounting the root filesystem. 1082 */ 1083 if (mp->mnt_flag & MNT_ROOTFS) 1084 return (EINVAL); 1085 return (dounmount(mp, uap->flags, td)); 1086 } 1087 1088 /* 1089 * Do the actual filesystem unmount. 1090 */ 1091 int 1092 dounmount(mp, flags, td) 1093 struct mount *mp; 1094 int flags; 1095 struct thread *td; 1096 { 1097 struct vnode *coveredvp, *fsrootvp; 1098 int error; 1099 int async_flag; 1100 1101 mtx_lock(&mountlist_mtx); 1102 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1103 mtx_unlock(&mountlist_mtx); 1104 return (EBUSY); 1105 } 1106 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1107 /* Allow filesystems to detect that a forced unmount is in progress. */ 1108 if (flags & MNT_FORCE) 1109 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1110 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1111 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), &mountlist_mtx, td); 1112 if (error) { 1113 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1114 if (mp->mnt_kern_flag & MNTK_MWAIT) 1115 wakeup(mp); 1116 return (error); 1117 } 1118 vn_start_write(NULL, &mp, V_WAIT); 1119 1120 if (mp->mnt_flag & MNT_EXPUBLIC) 1121 vfs_setpublicfs(NULL, NULL, NULL); 1122 1123 vfs_msync(mp, MNT_WAIT); 1124 async_flag = mp->mnt_flag & MNT_ASYNC; 1125 mp->mnt_flag &= ~MNT_ASYNC; 1126 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1127 if (mp->mnt_syncer != NULL) 1128 vrele(mp->mnt_syncer); 1129 /* 1130 * For forced unmounts, move process cdir/rdir refs on the fs root 1131 * vnode to the covered vnode. For non-forced unmounts we want 1132 * such references to cause an EBUSY error. 1133 */ 1134 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp) == 0) { 1135 if (mp->mnt_vnodecovered != NULL) 1136 checkdirs(fsrootvp, mp->mnt_vnodecovered); 1137 if (fsrootvp == rootvnode) { 1138 vrele(rootvnode); 1139 rootvnode = NULL; 1140 } 1141 vput(fsrootvp); 1142 } 1143 if (((mp->mnt_flag & MNT_RDONLY) || 1144 (error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) == 0) || 1145 (flags & MNT_FORCE)) { 1146 error = VFS_UNMOUNT(mp, flags, td); 1147 } 1148 vn_finished_write(mp); 1149 if (error) { 1150 /* Undo cdir/rdir and rootvnode changes made above. */ 1151 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp) == 0) { 1152 if (mp->mnt_vnodecovered != NULL) 1153 checkdirs(mp->mnt_vnodecovered, fsrootvp); 1154 if (rootvnode == NULL) { 1155 rootvnode = fsrootvp; 1156 vref(rootvnode); 1157 } 1158 vput(fsrootvp); 1159 } 1160 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 1161 (void) vfs_allocate_syncvnode(mp); 1162 mtx_lock(&mountlist_mtx); 1163 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1164 mp->mnt_flag |= async_flag; 1165 lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, 1166 &mountlist_mtx, td); 1167 if (mp->mnt_kern_flag & MNTK_MWAIT) 1168 wakeup(mp); 1169 return (error); 1170 } 1171 mtx_lock(&mountlist_mtx); 1172 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1173 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 1174 coveredvp->v_mountedhere = NULL; 1175 mtx_unlock(&mountlist_mtx); 1176 vfs_mount_destroy(mp, td); 1177 if (coveredvp != NULL) 1178 vrele(coveredvp); 1179 return (0); 1180 } 1181 1182 /* 1183 * Lookup a filesystem type, and if found allocate and initialize 1184 * a mount structure for it. 1185 * 1186 * Devname is usually updated by mount(8) after booting. 1187 */ 1188 int 1189 vfs_rootmountalloc(fstypename, devname, mpp) 1190 char *fstypename; 1191 char *devname; 1192 struct mount **mpp; 1193 { 1194 struct thread *td = curthread; /* XXX */ 1195 struct vfsconf *vfsp; 1196 struct mount *mp; 1197 int error; 1198 1199 if (fstypename == NULL) 1200 return (ENODEV); 1201 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 1202 if (!strcmp(vfsp->vfc_name, fstypename)) 1203 break; 1204 if (vfsp == NULL) 1205 return (ENODEV); 1206 error = vfs_mount_alloc(NULLVP, vfsp, "/", td, &mp); 1207 if (error) 1208 return (error); 1209 mp->mnt_flag |= MNT_RDONLY | MNT_ROOTFS; 1210 strlcpy(mp->mnt_stat.f_mntfromname, devname, MNAMELEN); 1211 *mpp = mp; 1212 return (0); 1213 } 1214 1215 /* 1216 * Find and mount the root filesystem 1217 */ 1218 void 1219 vfs_mountroot(void) 1220 { 1221 char *cp; 1222 int error, i; 1223 1224 g_waitidle(); 1225 1226 /* 1227 * The root filesystem information is compiled in, and we are 1228 * booted with instructions to use it. 1229 */ 1230 #ifdef ROOTDEVNAME 1231 if ((boothowto & RB_DFLTROOT) && !vfs_mountroot_try(ROOTDEVNAME)) 1232 return; 1233 #endif 1234 /* 1235 * We are booted with instructions to prompt for the root filesystem, 1236 * or to use the compiled-in default when it doesn't exist. 1237 */ 1238 if (boothowto & (RB_DFLTROOT | RB_ASKNAME)) { 1239 if (!vfs_mountroot_ask()) 1240 return; 1241 } 1242 1243 /* 1244 * We've been given the generic "use CDROM as root" flag. This is 1245 * necessary because one media may be used in many different 1246 * devices, so we need to search for them. 1247 */ 1248 if (boothowto & RB_CDROM) { 1249 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1250 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1251 return; 1252 } 1253 } 1254 1255 /* 1256 * Try to use the value read by the loader from /etc/fstab, or 1257 * supplied via some other means. This is the preferred 1258 * mechanism. 1259 */ 1260 if ((cp = getenv("vfs.root.mountfrom")) != NULL) { 1261 error = vfs_mountroot_try(cp); 1262 freeenv(cp); 1263 if (!error) 1264 return; 1265 } 1266 1267 /* 1268 * Try values that may have been computed by the machine-dependant 1269 * legacy code. 1270 */ 1271 if (!vfs_mountroot_try(rootdevnames[0])) 1272 return; 1273 if (!vfs_mountroot_try(rootdevnames[1])) 1274 return; 1275 1276 /* 1277 * If we have a compiled-in default, and haven't already tried it, try 1278 * it now. 1279 */ 1280 #ifdef ROOTDEVNAME 1281 if (!(boothowto & RB_DFLTROOT)) 1282 if (!vfs_mountroot_try(ROOTDEVNAME)) 1283 return; 1284 #endif 1285 1286 /* 1287 * Everything so far has failed, prompt on the console if we haven't 1288 * already tried that. 1289 */ 1290 if (!(boothowto & (RB_DFLTROOT | RB_ASKNAME)) && !vfs_mountroot_ask()) 1291 return; 1292 panic("Root mount failed, startup aborted."); 1293 } 1294 1295 /* 1296 * Mount (mountfrom) as the root filesystem. 1297 */ 1298 static int 1299 vfs_mountroot_try(char *mountfrom) 1300 { 1301 struct mount *mp; 1302 char *vfsname, *path; 1303 const char *devname; 1304 int error; 1305 char patt[32]; 1306 int s; 1307 1308 vfsname = NULL; 1309 path = NULL; 1310 mp = NULL; 1311 error = EINVAL; 1312 1313 if (mountfrom == NULL) 1314 return (error); /* don't complain */ 1315 1316 s = splcam(); /* Overkill, but annoying without it */ 1317 printf("Mounting root from %s\n", mountfrom); 1318 splx(s); 1319 1320 /* parse vfs name and path */ 1321 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1322 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1323 vfsname[0] = path[0] = 0; 1324 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1325 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1326 goto done; 1327 1328 /* allocate a root mount */ 1329 error = vfs_rootmountalloc(vfsname, path[0] != 0 ? path : ROOTNAME, 1330 &mp); 1331 if (error != 0) { 1332 printf("Can't allocate root mount for filesystem '%s': %d\n", 1333 vfsname, error); 1334 goto done; 1335 } 1336 1337 /* do our best to set rootdev */ 1338 if (path[0] != '\0' && setrootbyname(path)) 1339 printf("setrootbyname failed\n"); 1340 1341 /* If the root device is a type "memory disk", mount RW */ 1342 if (rootdev != NULL && devsw(rootdev) != NULL) { 1343 devname = devtoname(rootdev); 1344 if (devname[0] == 'm' && devname[1] == 'd') 1345 mp->mnt_flag &= ~MNT_RDONLY; 1346 } 1347 1348 error = VFS_MOUNT(mp, NULL, NULL, NULL, curthread); 1349 1350 done: 1351 if (vfsname != NULL) 1352 free(vfsname, M_MOUNT); 1353 if (path != NULL) 1354 free(path, M_MOUNT); 1355 if (error != 0) { 1356 if (mp != NULL) 1357 vfs_mount_destroy(mp, curthread); 1358 printf("Root mount failed: %d\n", error); 1359 } else { 1360 1361 /* register with list of mounted filesystems */ 1362 mtx_lock(&mountlist_mtx); 1363 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1364 mtx_unlock(&mountlist_mtx); 1365 1366 /* sanity check system clock against root fs timestamp */ 1367 inittodr(mp->mnt_time); 1368 vfs_unbusy(mp, curthread); 1369 error = VFS_START(mp, 0, curthread); 1370 } 1371 return (error); 1372 } 1373 1374 /* 1375 * Spin prompting on the console for a suitable root filesystem 1376 */ 1377 static int 1378 vfs_mountroot_ask(void) 1379 { 1380 char name[128]; 1381 1382 for(;;) { 1383 printf("\nManual root filesystem specification:\n"); 1384 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1385 #if defined(__i386__) || defined(__ia64__) 1386 printf(" eg. ufs:da0s1a\n"); 1387 #else 1388 printf(" eg. ufs:/dev/da0a\n"); 1389 #endif 1390 printf(" ? List valid disk boot devices\n"); 1391 printf(" <empty line> Abort manual input\n"); 1392 printf("\nmountroot> "); 1393 gets(name); 1394 if (name[0] == '\0') 1395 return (1); 1396 if (name[0] == '?') { 1397 printf("\nList of GEOM managed disk devices:\n "); 1398 g_dev_print(); 1399 continue; 1400 } 1401 if (!vfs_mountroot_try(name)) 1402 return (0); 1403 } 1404 } 1405 1406 /* 1407 * Local helper function for vfs_mountroot_ask. 1408 */ 1409 static void 1410 gets(char *cp) 1411 { 1412 char *lp; 1413 int c; 1414 1415 lp = cp; 1416 for (;;) { 1417 printf("%c", c = cngetc() & 0177); 1418 switch (c) { 1419 case -1: 1420 case '\n': 1421 case '\r': 1422 *lp++ = '\0'; 1423 return; 1424 case '\b': 1425 case '\177': 1426 if (lp > cp) { 1427 printf(" \b"); 1428 lp--; 1429 } 1430 continue; 1431 case '#': 1432 lp--; 1433 if (lp < cp) 1434 lp = cp; 1435 continue; 1436 case '@': 1437 case 'u' & 037: 1438 lp = cp; 1439 printf("%c", '\n'); 1440 continue; 1441 default: 1442 *lp++ = c; 1443 } 1444 } 1445 } 1446 1447 /* 1448 * Convert a given name to the cdev pointer of the device, which is probably 1449 * but not by definition, a disk. Mount a DEVFS (on nothing), look the name 1450 * up, extract the cdev from the vnode and unmount it again. Unfortunately 1451 * we cannot use the vnode directly (because we unmount the DEVFS again) 1452 * so the filesystems still have to do the bdevvp() stunt. 1453 */ 1454 struct cdev * 1455 getdiskbyname(char *name) 1456 { 1457 char *cp = name; 1458 struct cdev *dev = NULL; 1459 struct thread *td = curthread; 1460 struct vfsconf *vfsp; 1461 struct mount *mp = NULL; 1462 struct vnode *vroot = NULL; 1463 struct nameidata nid; 1464 int error; 1465 1466 if (!bcmp(cp, "/dev/", 5)) 1467 cp += 5; 1468 1469 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 1470 if (!strcmp(vfsp->vfc_name, "devfs")) 1471 break; 1472 do { 1473 if (vfsp == NULL) 1474 break; 1475 error = vfs_mount_alloc(NULLVP, vfsp, "/dev", td, &mp); 1476 if (error) 1477 break; 1478 mp->mnt_flag |= MNT_RDONLY; 1479 1480 error = VFS_NMOUNT(mp, NULL, curthread); 1481 if (error) 1482 break; 1483 VFS_START(mp, 0, td); 1484 VFS_ROOT(mp, &vroot); 1485 VOP_UNLOCK(vroot, 0, td); 1486 1487 NDINIT(&nid, LOOKUP, NOCACHE|FOLLOW, 1488 UIO_SYSSPACE, cp, curthread); 1489 nid.ni_startdir = vroot; 1490 nid.ni_pathlen = strlen(cp); 1491 nid.ni_cnd.cn_cred = curthread->td_ucred; 1492 nid.ni_cnd.cn_nameptr = cp; 1493 1494 error = lookup(&nid); 1495 if (error) 1496 break; 1497 dev = vn_todev (nid.ni_vp); 1498 NDFREE(&nid, 0); 1499 } while (0); 1500 1501 if (vroot != NULL) 1502 VFS_UNMOUNT(mp, 0, td); 1503 if (mp != NULL) 1504 vfs_mount_destroy(mp, td); 1505 return (dev); 1506 } 1507 1508 /* 1509 * Set rootdev to match (name), given that we expect it to 1510 * refer to a disk-like device. 1511 */ 1512 static int 1513 setrootbyname(char *name) 1514 { 1515 struct cdev *diskdev; 1516 1517 diskdev = getdiskbyname(name); 1518 if (diskdev != NULL) { 1519 rootdev = diskdev; 1520 return (0); 1521 } 1522 1523 return (1); 1524 } 1525 1526 /* Show the struct cdev *for a disk specified by name */ 1527 #ifdef DDB 1528 DB_SHOW_COMMAND(disk, db_getdiskbyname) 1529 { 1530 struct cdev *dev; 1531 1532 if (modif[0] == '\0') { 1533 db_error("usage: show disk/devicename"); 1534 return; 1535 } 1536 dev = getdiskbyname(modif); 1537 if (dev != NULL) 1538 db_printf("struct cdev *= %p\n", dev); 1539 else 1540 db_printf("No disk device matched.\n"); 1541 } 1542 #endif 1543 1544 /* 1545 * Get a mount option by its name. 1546 * 1547 * Return 0 if the option was found, ENOENT otherwise. 1548 * If len is non-NULL it will be filled with the length 1549 * of the option. If buf is non-NULL, it will be filled 1550 * with the address of the option. 1551 */ 1552 int 1553 vfs_getopt(opts, name, buf, len) 1554 struct vfsoptlist *opts; 1555 const char *name; 1556 void **buf; 1557 int *len; 1558 { 1559 struct vfsopt *opt; 1560 1561 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1562 1563 TAILQ_FOREACH(opt, opts, link) { 1564 if (strcmp(name, opt->name) == 0) { 1565 if (len != NULL) 1566 *len = opt->len; 1567 if (buf != NULL) 1568 *buf = opt->value; 1569 return (0); 1570 } 1571 } 1572 return (ENOENT); 1573 } 1574 1575 /* 1576 * Find and copy a mount option. 1577 * 1578 * The size of the buffer has to be specified 1579 * in len, if it is not the same length as the 1580 * mount option, EINVAL is returned. 1581 * Returns ENOENT if the option is not found. 1582 */ 1583 int 1584 vfs_copyopt(opts, name, dest, len) 1585 struct vfsoptlist *opts; 1586 const char *name; 1587 void *dest; 1588 int len; 1589 { 1590 struct vfsopt *opt; 1591 1592 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1593 1594 TAILQ_FOREACH(opt, opts, link) { 1595 if (strcmp(name, opt->name) == 0) { 1596 if (len != opt->len) 1597 return (EINVAL); 1598 bcopy(opt->value, dest, opt->len); 1599 return (0); 1600 } 1601 } 1602 return (ENOENT); 1603 } 1604