1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2010 Marcel Moolenaar 5 * Copyright (c) 1999-2004 Poul-Henning Kamp 6 * Copyright (c) 1999 Michael Smith 7 * Copyright (c) 1989, 1993 8 * The Regents of the University of California. All rights reserved. 9 * (c) UNIX System Laboratories, Inc. 10 * All or some portions of this file are derived from material licensed 11 * to the University of California by American Telephone and Telegraph 12 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 13 * the permission of UNIX System Laboratories, Inc. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40 #include "opt_rootdevname.h" 41 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include <sys/param.h> 46 #include <sys/conf.h> 47 #include <sys/cons.h> 48 #include <sys/fcntl.h> 49 #include <sys/jail.h> 50 #include <sys/kernel.h> 51 #include <sys/malloc.h> 52 #include <sys/mdioctl.h> 53 #include <sys/mount.h> 54 #include <sys/mutex.h> 55 #include <sys/namei.h> 56 #include <sys/priv.h> 57 #include <sys/proc.h> 58 #include <sys/filedesc.h> 59 #include <sys/reboot.h> 60 #include <sys/sbuf.h> 61 #include <sys/stat.h> 62 #include <sys/syscallsubr.h> 63 #include <sys/sysproto.h> 64 #include <sys/sx.h> 65 #include <sys/sysctl.h> 66 #include <sys/sysent.h> 67 #include <sys/systm.h> 68 #include <sys/vnode.h> 69 70 #include <geom/geom.h> 71 72 /* 73 * The root filesystem is detailed in the kernel environment variable 74 * vfs.root.mountfrom, which is expected to be in the general format 75 * 76 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 77 * vfsname := the name of a VFS known to the kernel and capable 78 * of being mounted as root 79 * path := disk device name or other data used by the filesystem 80 * to locate its physical store 81 * 82 * If the environment variable vfs.root.mountfrom is a space separated list, 83 * each list element is tried in turn and the root filesystem will be mounted 84 * from the first one that succeeds. 85 * 86 * The environment variable vfs.root.mountfrom.options is a comma delimited 87 * set of string mount options. These mount options must be parseable 88 * by nmount() in the kernel. 89 */ 90 91 static int parse_mount(char **); 92 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 93 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS); 94 static void vfs_mountroot_wait(void); 95 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev); 96 97 /* 98 * The vnode of the system's root (/ in the filesystem, without chroot 99 * active.) 100 */ 101 struct vnode *rootvnode; 102 103 /* 104 * Mount of the system's /dev. 105 */ 106 struct mount *rootdevmp; 107 108 char *rootdevnames[2] = {NULL, NULL}; 109 110 struct mtx root_holds_mtx; 111 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 112 113 struct root_hold_token { 114 const char *who; 115 LIST_ENTRY(root_hold_token) list; 116 }; 117 118 static LIST_HEAD(, root_hold_token) root_holds = 119 LIST_HEAD_INITIALIZER(root_holds); 120 121 enum action { 122 A_CONTINUE, 123 A_PANIC, 124 A_REBOOT, 125 A_RETRY 126 }; 127 128 static enum action root_mount_onfail = A_CONTINUE; 129 130 static int root_mount_mddev; 131 static int root_mount_complete; 132 133 /* By default wait up to 3 seconds for devices to appear. */ 134 static int root_mount_timeout = 3; 135 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 136 137 static int root_mount_always_wait = 0; 138 SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN, 139 &root_mount_always_wait, 0, 140 "Wait for root mount holds even if the root device already exists"); 141 142 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold, 143 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 144 NULL, 0, sysctl_vfs_root_mount_hold, "A", 145 "List of root mount hold tokens"); 146 147 static int 148 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS) 149 { 150 struct sbuf sb; 151 struct root_hold_token *h; 152 int error; 153 154 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 155 156 mtx_lock(&root_holds_mtx); 157 LIST_FOREACH(h, &root_holds, list) { 158 if (h != LIST_FIRST(&root_holds)) 159 sbuf_putc(&sb, ' '); 160 sbuf_printf(&sb, "%s", h->who); 161 } 162 mtx_unlock(&root_holds_mtx); 163 164 error = sbuf_finish(&sb); 165 if (error == 0) 166 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 167 sbuf_delete(&sb); 168 return (error); 169 } 170 171 struct root_hold_token * 172 root_mount_hold(const char *identifier) 173 { 174 struct root_hold_token *h; 175 176 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 177 h->who = identifier; 178 mtx_lock(&root_holds_mtx); 179 TSHOLD("root mount"); 180 LIST_INSERT_HEAD(&root_holds, h, list); 181 mtx_unlock(&root_holds_mtx); 182 return (h); 183 } 184 185 void 186 root_mount_rel(struct root_hold_token *h) 187 { 188 189 if (h == NULL) 190 return; 191 192 mtx_lock(&root_holds_mtx); 193 LIST_REMOVE(h, list); 194 TSRELEASE("root mount"); 195 wakeup(&root_holds); 196 mtx_unlock(&root_holds_mtx); 197 free(h, M_DEVBUF); 198 } 199 200 int 201 root_mounted(void) 202 { 203 204 /* No mutex is acquired here because int stores are atomic. */ 205 return (root_mount_complete); 206 } 207 208 static void 209 set_rootvnode(void) 210 { 211 struct proc *p; 212 213 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 214 panic("Cannot find root vnode"); 215 216 VOP_UNLOCK(rootvnode, 0); 217 218 p = curthread->td_proc; 219 FILEDESC_XLOCK(p->p_fd); 220 221 if (p->p_fd->fd_cdir != NULL) 222 vrele(p->p_fd->fd_cdir); 223 p->p_fd->fd_cdir = rootvnode; 224 VREF(rootvnode); 225 226 if (p->p_fd->fd_rdir != NULL) 227 vrele(p->p_fd->fd_rdir); 228 p->p_fd->fd_rdir = rootvnode; 229 VREF(rootvnode); 230 231 FILEDESC_XUNLOCK(p->p_fd); 232 } 233 234 static int 235 vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 236 { 237 struct vfsoptlist *opts; 238 struct vfsconf *vfsp; 239 struct mount *mp; 240 int error; 241 242 *mpp = NULL; 243 244 if (rootdevmp != NULL) { 245 /* 246 * Already have /dev; this happens during rerooting. 247 */ 248 error = vfs_busy(rootdevmp, 0); 249 if (error != 0) 250 return (error); 251 *mpp = rootdevmp; 252 } else { 253 vfsp = vfs_byname("devfs"); 254 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 255 if (vfsp == NULL) 256 return (ENOENT); 257 258 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 259 260 error = VFS_MOUNT(mp); 261 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 262 if (error) 263 return (error); 264 265 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 266 TAILQ_INIT(opts); 267 mp->mnt_opt = opts; 268 269 mtx_lock(&mountlist_mtx); 270 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 271 mtx_unlock(&mountlist_mtx); 272 273 *mpp = mp; 274 rootdevmp = mp; 275 } 276 277 set_rootvnode(); 278 279 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 280 if (error) 281 printf("kern_symlink /dev -> / returns %d\n", error); 282 283 return (error); 284 } 285 286 static void 287 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 288 { 289 struct nameidata nd; 290 struct mount *mporoot, *mpnroot; 291 struct vnode *vp, *vporoot, *vpdevfs; 292 char *fspath; 293 int error; 294 295 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 296 297 /* Shuffle the mountlist. */ 298 mtx_lock(&mountlist_mtx); 299 mporoot = TAILQ_FIRST(&mountlist); 300 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 301 if (mporoot != mpdevfs) { 302 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 303 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 304 } 305 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 306 mtx_unlock(&mountlist_mtx); 307 308 cache_purgevfs(mporoot, true); 309 if (mporoot != mpdevfs) 310 cache_purgevfs(mpdevfs, true); 311 312 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot); 313 314 VI_LOCK(vporoot); 315 vporoot->v_iflag &= ~VI_MOUNT; 316 VI_UNLOCK(vporoot); 317 vporoot->v_mountedhere = NULL; 318 mporoot->mnt_flag &= ~MNT_ROOTFS; 319 mporoot->mnt_vnodecovered = NULL; 320 vput(vporoot); 321 322 /* Set up the new rootvnode, and purge the cache */ 323 mpnroot->mnt_vnodecovered = NULL; 324 set_rootvnode(); 325 cache_purgevfs(rootvnode->v_mount, true); 326 327 if (mporoot != mpdevfs) { 328 /* Remount old root under /.mount or /mnt */ 329 fspath = "/.mount"; 330 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 331 fspath, td); 332 error = namei(&nd); 333 if (error) { 334 NDFREE(&nd, NDF_ONLY_PNBUF); 335 fspath = "/mnt"; 336 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 337 fspath, td); 338 error = namei(&nd); 339 } 340 if (!error) { 341 vp = nd.ni_vp; 342 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 343 if (!error) 344 error = vinvalbuf(vp, V_SAVE, 0, 0); 345 if (!error) { 346 cache_purge(vp); 347 mporoot->mnt_vnodecovered = vp; 348 vp->v_mountedhere = mporoot; 349 strlcpy(mporoot->mnt_stat.f_mntonname, 350 fspath, MNAMELEN); 351 VOP_UNLOCK(vp, 0); 352 } else 353 vput(vp); 354 } 355 NDFREE(&nd, NDF_ONLY_PNBUF); 356 357 if (error) 358 printf("mountroot: unable to remount previous root " 359 "under /.mount or /mnt (error %d)\n", error); 360 } 361 362 /* Remount devfs under /dev */ 363 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 364 error = namei(&nd); 365 if (!error) { 366 vp = nd.ni_vp; 367 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 368 if (!error) 369 error = vinvalbuf(vp, V_SAVE, 0, 0); 370 if (!error) { 371 vpdevfs = mpdevfs->mnt_vnodecovered; 372 if (vpdevfs != NULL) { 373 cache_purge(vpdevfs); 374 vpdevfs->v_mountedhere = NULL; 375 vrele(vpdevfs); 376 } 377 mpdevfs->mnt_vnodecovered = vp; 378 vp->v_mountedhere = mpdevfs; 379 VOP_UNLOCK(vp, 0); 380 } else 381 vput(vp); 382 } 383 if (error) 384 printf("mountroot: unable to remount devfs under /dev " 385 "(error %d)\n", error); 386 NDFREE(&nd, NDF_ONLY_PNBUF); 387 388 if (mporoot == mpdevfs) { 389 vfs_unbusy(mpdevfs); 390 /* Unlink the no longer needed /dev/dev -> / symlink */ 391 error = kern_unlinkat(td, AT_FDCWD, "/dev/dev", 392 UIO_SYSSPACE, 0); 393 if (error) 394 printf("mountroot: unable to unlink /dev/dev " 395 "(error %d)\n", error); 396 } 397 } 398 399 /* 400 * Configuration parser. 401 */ 402 403 /* Parser character classes. */ 404 #define CC_WHITESPACE -1 405 #define CC_NONWHITESPACE -2 406 407 /* Parse errors. */ 408 #define PE_EOF -1 409 #define PE_EOL -2 410 411 static __inline int 412 parse_peek(char **conf) 413 { 414 415 return (**conf); 416 } 417 418 static __inline void 419 parse_poke(char **conf, int c) 420 { 421 422 **conf = c; 423 } 424 425 static __inline void 426 parse_advance(char **conf) 427 { 428 429 (*conf)++; 430 } 431 432 static int 433 parse_skipto(char **conf, int mc) 434 { 435 int c, match; 436 437 while (1) { 438 c = parse_peek(conf); 439 if (c == 0) 440 return (PE_EOF); 441 switch (mc) { 442 case CC_WHITESPACE: 443 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 444 break; 445 case CC_NONWHITESPACE: 446 if (c == '\n') 447 return (PE_EOL); 448 match = (c != ' ' && c != '\t') ? 1 : 0; 449 break; 450 default: 451 match = (c == mc) ? 1 : 0; 452 break; 453 } 454 if (match) 455 break; 456 parse_advance(conf); 457 } 458 return (0); 459 } 460 461 static int 462 parse_token(char **conf, char **tok) 463 { 464 char *p; 465 size_t len; 466 int error; 467 468 *tok = NULL; 469 error = parse_skipto(conf, CC_NONWHITESPACE); 470 if (error) 471 return (error); 472 p = *conf; 473 error = parse_skipto(conf, CC_WHITESPACE); 474 len = *conf - p; 475 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 476 bcopy(p, *tok, len); 477 return (0); 478 } 479 480 static void 481 parse_dir_ask_printenv(const char *var) 482 { 483 char *val; 484 485 val = kern_getenv(var); 486 if (val != NULL) { 487 printf(" %s=%s\n", var, val); 488 freeenv(val); 489 } 490 } 491 492 static int 493 parse_dir_ask(char **conf) 494 { 495 char name[80]; 496 char *mnt; 497 int error; 498 499 vfs_mountroot_wait(); 500 501 printf("\nLoader variables:\n"); 502 parse_dir_ask_printenv("vfs.root.mountfrom"); 503 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 504 505 printf("\nManual root filesystem specification:\n"); 506 printf(" <fstype>:<device> [options]\n"); 507 printf(" Mount <device> using filesystem <fstype>\n"); 508 printf(" and with the specified (optional) option list.\n"); 509 printf("\n"); 510 printf(" eg. ufs:/dev/da0s1a\n"); 511 printf(" zfs:tank\n"); 512 printf(" cd9660:/dev/cd0 ro\n"); 513 printf(" (which is equivalent to: "); 514 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 515 printf("\n"); 516 printf(" ? List valid disk boot devices\n"); 517 printf(" . Yield 1 second (for background tasks)\n"); 518 printf(" <empty line> Abort manual input\n"); 519 520 do { 521 error = EINVAL; 522 printf("\nmountroot> "); 523 cngets(name, sizeof(name), GETS_ECHO); 524 if (name[0] == '\0') 525 break; 526 if (name[0] == '?' && name[1] == '\0') { 527 printf("\nList of GEOM managed disk devices:\n "); 528 g_dev_print(); 529 continue; 530 } 531 if (name[0] == '.' && name[1] == '\0') { 532 pause("rmask", hz); 533 continue; 534 } 535 mnt = name; 536 error = parse_mount(&mnt); 537 if (error == -1) 538 printf("Invalid file system specification.\n"); 539 } while (error != 0); 540 541 return (error); 542 } 543 544 static int 545 parse_dir_md(char **conf) 546 { 547 struct stat sb; 548 struct thread *td; 549 struct md_ioctl *mdio; 550 char *path, *tok; 551 int error, fd, len; 552 553 td = curthread; 554 555 error = parse_token(conf, &tok); 556 if (error) 557 return (error); 558 559 len = strlen(tok); 560 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 561 path = (void *)(mdio + 1); 562 bcopy(tok, path, len); 563 free(tok, M_TEMP); 564 565 /* Get file status. */ 566 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 567 if (error) 568 goto out; 569 570 /* Open /dev/mdctl so that we can attach/detach. */ 571 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 572 O_RDWR, 0); 573 if (error) 574 goto out; 575 576 fd = td->td_retval[0]; 577 mdio->md_version = MDIOVERSION; 578 mdio->md_type = MD_VNODE; 579 580 if (root_mount_mddev != -1) { 581 mdio->md_unit = root_mount_mddev; 582 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 583 /* Ignore errors. We don't care. */ 584 root_mount_mddev = -1; 585 } 586 587 mdio->md_file = (void *)(mdio + 1); 588 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 589 mdio->md_mediasize = sb.st_size; 590 mdio->md_unit = 0; 591 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 592 if (error) 593 goto out; 594 595 if (mdio->md_unit > 9) { 596 printf("rootmount: too many md units\n"); 597 mdio->md_file = NULL; 598 mdio->md_options = 0; 599 mdio->md_mediasize = 0; 600 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 601 /* Ignore errors. We don't care. */ 602 error = ERANGE; 603 goto out; 604 } 605 606 root_mount_mddev = mdio->md_unit; 607 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 608 609 error = kern_close(td, fd); 610 611 out: 612 free(mdio, M_TEMP); 613 return (error); 614 } 615 616 static int 617 parse_dir_onfail(char **conf) 618 { 619 char *action; 620 int error; 621 622 error = parse_token(conf, &action); 623 if (error) 624 return (error); 625 626 if (!strcmp(action, "continue")) 627 root_mount_onfail = A_CONTINUE; 628 else if (!strcmp(action, "panic")) 629 root_mount_onfail = A_PANIC; 630 else if (!strcmp(action, "reboot")) 631 root_mount_onfail = A_REBOOT; 632 else if (!strcmp(action, "retry")) 633 root_mount_onfail = A_RETRY; 634 else { 635 printf("rootmount: %s: unknown action\n", action); 636 error = EINVAL; 637 } 638 639 free(action, M_TEMP); 640 return (0); 641 } 642 643 static int 644 parse_dir_timeout(char **conf) 645 { 646 char *tok, *endtok; 647 long secs; 648 int error; 649 650 error = parse_token(conf, &tok); 651 if (error) 652 return (error); 653 654 secs = strtol(tok, &endtok, 0); 655 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 656 if (!error) 657 root_mount_timeout = secs; 658 free(tok, M_TEMP); 659 return (error); 660 } 661 662 static int 663 parse_directive(char **conf) 664 { 665 char *dir; 666 int error; 667 668 error = parse_token(conf, &dir); 669 if (error) 670 return (error); 671 672 if (strcmp(dir, ".ask") == 0) 673 error = parse_dir_ask(conf); 674 else if (strcmp(dir, ".md") == 0) 675 error = parse_dir_md(conf); 676 else if (strcmp(dir, ".onfail") == 0) 677 error = parse_dir_onfail(conf); 678 else if (strcmp(dir, ".timeout") == 0) 679 error = parse_dir_timeout(conf); 680 else { 681 printf("mountroot: invalid directive `%s'\n", dir); 682 /* Ignore the rest of the line. */ 683 (void)parse_skipto(conf, '\n'); 684 error = EINVAL; 685 } 686 free(dir, M_TEMP); 687 return (error); 688 } 689 690 static int 691 parse_mount_dev_present(const char *dev) 692 { 693 struct nameidata nd; 694 int error; 695 696 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 697 error = namei(&nd); 698 if (!error) 699 vput(nd.ni_vp); 700 NDFREE(&nd, NDF_ONLY_PNBUF); 701 return (error != 0) ? 0 : 1; 702 } 703 704 #define ERRMSGL 255 705 static int 706 parse_mount(char **conf) 707 { 708 char *errmsg; 709 struct mntarg *ma; 710 char *dev, *fs, *opts, *tok; 711 int delay, error, timeout; 712 713 error = parse_token(conf, &tok); 714 if (error) 715 return (error); 716 fs = tok; 717 error = parse_skipto(&tok, ':'); 718 if (error) { 719 free(fs, M_TEMP); 720 return (error); 721 } 722 parse_poke(&tok, '\0'); 723 parse_advance(&tok); 724 dev = tok; 725 726 if (root_mount_mddev != -1) { 727 /* Handle substitution for the md unit number. */ 728 tok = strstr(dev, "md#"); 729 if (tok != NULL) 730 tok[2] = '0' + root_mount_mddev; 731 } 732 733 /* Parse options. */ 734 error = parse_token(conf, &tok); 735 opts = (error == 0) ? tok : NULL; 736 737 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 738 (opts != NULL) ? opts : ""); 739 740 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 741 742 if (vfs_byname(fs) == NULL) { 743 strlcpy(errmsg, "unknown file system", ERRMSGL); 744 error = ENOENT; 745 goto out; 746 } 747 748 error = vfs_mountroot_wait_if_neccessary(fs, dev); 749 if (error != 0) 750 goto out; 751 752 delay = hz / 10; 753 timeout = root_mount_timeout * hz; 754 755 for (;;) { 756 ma = NULL; 757 ma = mount_arg(ma, "fstype", fs, -1); 758 ma = mount_arg(ma, "fspath", "/", -1); 759 ma = mount_arg(ma, "from", dev, -1); 760 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 761 ma = mount_arg(ma, "ro", NULL, 0); 762 ma = parse_mountroot_options(ma, opts); 763 764 error = kernel_mount(ma, MNT_ROOTFS); 765 if (error == 0 || timeout <= 0) 766 break; 767 768 if (root_mount_timeout * hz == timeout || 769 (bootverbose && timeout % hz == 0)) { 770 printf("Mounting from %s:%s failed with error %d; " 771 "retrying for %d more second%s\n", fs, dev, error, 772 timeout / hz, (timeout / hz > 1) ? "s" : ""); 773 } 774 pause("rmretry", delay); 775 timeout -= delay; 776 } 777 out: 778 if (error) { 779 printf("Mounting from %s:%s failed with error %d", 780 fs, dev, error); 781 if (errmsg[0] != '\0') 782 printf(": %s", errmsg); 783 printf(".\n"); 784 } 785 free(fs, M_TEMP); 786 free(errmsg, M_TEMP); 787 if (opts != NULL) 788 free(opts, M_TEMP); 789 /* kernel_mount can return -1 on error. */ 790 return ((error < 0) ? EDOOFUS : error); 791 } 792 #undef ERRMSGL 793 794 static int 795 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 796 { 797 struct mount *mp; 798 char *conf; 799 int error; 800 801 root_mount_mddev = -1; 802 803 retry: 804 conf = sbuf_data(sb); 805 mp = TAILQ_NEXT(mpdevfs, mnt_list); 806 error = (mp == NULL) ? 0 : EDOOFUS; 807 root_mount_onfail = A_CONTINUE; 808 while (mp == NULL) { 809 error = parse_skipto(&conf, CC_NONWHITESPACE); 810 if (error == PE_EOL) { 811 parse_advance(&conf); 812 continue; 813 } 814 if (error < 0) 815 break; 816 switch (parse_peek(&conf)) { 817 case '#': 818 error = parse_skipto(&conf, '\n'); 819 break; 820 case '.': 821 error = parse_directive(&conf); 822 break; 823 default: 824 error = parse_mount(&conf); 825 if (error == -1) { 826 printf("mountroot: invalid file system " 827 "specification.\n"); 828 error = 0; 829 } 830 break; 831 } 832 if (error < 0) 833 break; 834 /* Ignore any trailing garbage on the line. */ 835 if (parse_peek(&conf) != '\n') { 836 printf("mountroot: advancing to next directive...\n"); 837 (void)parse_skipto(&conf, '\n'); 838 } 839 mp = TAILQ_NEXT(mpdevfs, mnt_list); 840 } 841 if (mp != NULL) 842 return (0); 843 844 /* 845 * We failed to mount (a new) root. 846 */ 847 switch (root_mount_onfail) { 848 case A_CONTINUE: 849 break; 850 case A_PANIC: 851 panic("mountroot: unable to (re-)mount root."); 852 /* NOTREACHED */ 853 case A_RETRY: 854 goto retry; 855 case A_REBOOT: 856 kern_reboot(RB_NOSYNC); 857 /* NOTREACHED */ 858 } 859 860 return (error); 861 } 862 863 static void 864 vfs_mountroot_conf0(struct sbuf *sb) 865 { 866 char *s, *tok, *mnt, *opt; 867 int error; 868 869 sbuf_printf(sb, ".onfail panic\n"); 870 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 871 if (boothowto & RB_ASKNAME) 872 sbuf_printf(sb, ".ask\n"); 873 #ifdef ROOTDEVNAME 874 if (boothowto & RB_DFLTROOT) 875 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 876 #endif 877 if (boothowto & RB_CDROM) { 878 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 879 sbuf_printf(sb, ".timeout 0\n"); 880 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 881 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 882 } 883 s = kern_getenv("vfs.root.mountfrom"); 884 if (s != NULL) { 885 opt = kern_getenv("vfs.root.mountfrom.options"); 886 tok = s; 887 error = parse_token(&tok, &mnt); 888 while (!error) { 889 sbuf_printf(sb, "%s %s\n", mnt, 890 (opt != NULL) ? opt : ""); 891 free(mnt, M_TEMP); 892 error = parse_token(&tok, &mnt); 893 } 894 if (opt != NULL) 895 freeenv(opt); 896 freeenv(s); 897 } 898 if (rootdevnames[0] != NULL) 899 sbuf_printf(sb, "%s\n", rootdevnames[0]); 900 if (rootdevnames[1] != NULL) 901 sbuf_printf(sb, "%s\n", rootdevnames[1]); 902 #ifdef ROOTDEVNAME 903 if (!(boothowto & RB_DFLTROOT)) 904 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 905 #endif 906 if (!(boothowto & RB_ASKNAME)) 907 sbuf_printf(sb, ".ask\n"); 908 } 909 910 static int 911 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 912 { 913 static char buf[128]; 914 struct nameidata nd; 915 off_t ofs; 916 ssize_t resid; 917 int error, flags, len; 918 919 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 920 flags = FREAD; 921 error = vn_open(&nd, &flags, 0, NULL); 922 if (error) 923 return (error); 924 925 NDFREE(&nd, NDF_ONLY_PNBUF); 926 ofs = 0; 927 len = sizeof(buf) - 1; 928 while (1) { 929 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 930 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 931 NOCRED, &resid, td); 932 if (error) 933 break; 934 if (resid == len) 935 break; 936 buf[len - resid] = 0; 937 sbuf_printf(sb, "%s", buf); 938 ofs += len - resid; 939 } 940 941 VOP_UNLOCK(nd.ni_vp, 0); 942 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 943 return (error); 944 } 945 946 static void 947 vfs_mountroot_wait(void) 948 { 949 struct root_hold_token *h; 950 struct timeval lastfail; 951 int curfail; 952 953 TSENTER(); 954 955 curfail = 0; 956 while (1) { 957 g_waitidle(); 958 mtx_lock(&root_holds_mtx); 959 if (LIST_EMPTY(&root_holds)) { 960 mtx_unlock(&root_holds_mtx); 961 break; 962 } 963 if (ppsratecheck(&lastfail, &curfail, 1)) { 964 printf("Root mount waiting for:"); 965 LIST_FOREACH(h, &root_holds, list) 966 printf(" %s", h->who); 967 printf("\n"); 968 } 969 TSWAIT("root mount"); 970 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 971 hz); 972 TSUNWAIT("root mount"); 973 } 974 975 TSEXIT(); 976 } 977 978 static int 979 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 980 { 981 int delay, timeout; 982 983 /* 984 * In case of ZFS and NFS we don't have a way to wait for 985 * specific device. Also do the wait if the user forced that 986 * behaviour by setting vfs.root_mount_always_wait=1. 987 */ 988 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 989 dev[0] == '\0' || root_mount_always_wait != 0) { 990 vfs_mountroot_wait(); 991 return (0); 992 } 993 994 /* 995 * Otherwise, no point in waiting if the device is already there. 996 * Note that we must wait for GEOM to finish reconfiguring itself, 997 * eg for geom_part(4) to finish tasting. 998 */ 999 g_waitidle(); 1000 if (parse_mount_dev_present(dev)) 1001 return (0); 1002 1003 /* 1004 * No luck. Let's wait. This code looks weird, but it's that way 1005 * to behave exactly as it used to work before. 1006 */ 1007 vfs_mountroot_wait(); 1008 printf("mountroot: waiting for device %s...\n", dev); 1009 delay = hz / 10; 1010 timeout = root_mount_timeout * hz; 1011 do { 1012 pause("rmdev", delay); 1013 timeout -= delay; 1014 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1015 1016 if (timeout <= 0) 1017 return (ENODEV); 1018 1019 return (0); 1020 } 1021 1022 void 1023 vfs_mountroot(void) 1024 { 1025 struct mount *mp; 1026 struct sbuf *sb; 1027 struct thread *td; 1028 time_t timebase; 1029 int error; 1030 1031 mtx_assert(&Giant, MA_NOTOWNED); 1032 1033 TSENTER(); 1034 1035 td = curthread; 1036 1037 sb = sbuf_new_auto(); 1038 vfs_mountroot_conf0(sb); 1039 sbuf_finish(sb); 1040 1041 error = vfs_mountroot_devfs(td, &mp); 1042 while (!error) { 1043 error = vfs_mountroot_parse(sb, mp); 1044 if (!error) { 1045 vfs_mountroot_shuffle(td, mp); 1046 sbuf_clear(sb); 1047 error = vfs_mountroot_readconf(td, sb); 1048 sbuf_finish(sb); 1049 } 1050 } 1051 1052 sbuf_delete(sb); 1053 1054 /* 1055 * Iterate over all currently mounted file systems and use 1056 * the time stamp found to check and/or initialize the RTC. 1057 * Call inittodr() only once and pass it the largest of the 1058 * timestamps we encounter. 1059 */ 1060 timebase = 0; 1061 mtx_lock(&mountlist_mtx); 1062 mp = TAILQ_FIRST(&mountlist); 1063 while (mp != NULL) { 1064 if (mp->mnt_time > timebase) 1065 timebase = mp->mnt_time; 1066 mp = TAILQ_NEXT(mp, mnt_list); 1067 } 1068 mtx_unlock(&mountlist_mtx); 1069 inittodr(timebase); 1070 1071 /* Keep prison0's root in sync with the global rootvnode. */ 1072 mtx_lock(&prison0.pr_mtx); 1073 prison0.pr_root = rootvnode; 1074 vref(prison0.pr_root); 1075 mtx_unlock(&prison0.pr_mtx); 1076 1077 mtx_lock(&root_holds_mtx); 1078 atomic_store_rel_int(&root_mount_complete, 1); 1079 wakeup(&root_mount_complete); 1080 mtx_unlock(&root_holds_mtx); 1081 1082 EVENTHANDLER_INVOKE(mountroot); 1083 1084 TSEXIT(); 1085 } 1086 1087 static struct mntarg * 1088 parse_mountroot_options(struct mntarg *ma, const char *options) 1089 { 1090 char *p; 1091 char *name, *name_arg; 1092 char *val, *val_arg; 1093 char *opts; 1094 1095 if (options == NULL || options[0] == '\0') 1096 return (ma); 1097 1098 p = opts = strdup(options, M_MOUNT); 1099 if (opts == NULL) { 1100 return (ma); 1101 } 1102 1103 while((name = strsep(&p, ",")) != NULL) { 1104 if (name[0] == '\0') 1105 break; 1106 1107 val = strchr(name, '='); 1108 if (val != NULL) { 1109 *val = '\0'; 1110 ++val; 1111 } 1112 if( strcmp(name, "rw") == 0 || 1113 strcmp(name, "noro") == 0) { 1114 /* 1115 * The first time we mount the root file system, 1116 * we need to mount 'ro', so We need to ignore 1117 * 'rw' and 'noro' mount options. 1118 */ 1119 continue; 1120 } 1121 name_arg = strdup(name, M_MOUNT); 1122 val_arg = NULL; 1123 if (val != NULL) 1124 val_arg = strdup(val, M_MOUNT); 1125 1126 ma = mount_arg(ma, name_arg, val_arg, 1127 (val_arg != NULL ? -1 : 0)); 1128 } 1129 free(opts, M_MOUNT); 1130 return (ma); 1131 } 1132