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/eventhandler.h> 49 #include <sys/fcntl.h> 50 #include <sys/jail.h> 51 #include <sys/kernel.h> 52 #include <sys/malloc.h> 53 #include <sys/mdioctl.h> 54 #include <sys/mount.h> 55 #include <sys/mutex.h> 56 #include <sys/namei.h> 57 #include <sys/priv.h> 58 #include <sys/proc.h> 59 #include <sys/filedesc.h> 60 #include <sys/reboot.h> 61 #include <sys/sbuf.h> 62 #include <sys/stat.h> 63 #include <sys/syscallsubr.h> 64 #include <sys/sysproto.h> 65 #include <sys/sx.h> 66 #include <sys/sysctl.h> 67 #include <sys/sysent.h> 68 #include <sys/systm.h> 69 #include <sys/vnode.h> 70 71 #include <geom/geom.h> 72 73 /* 74 * The root filesystem is detailed in the kernel environment variable 75 * vfs.root.mountfrom, which is expected to be in the general format 76 * 77 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 78 * vfsname := the name of a VFS known to the kernel and capable 79 * of being mounted as root 80 * path := disk device name or other data used by the filesystem 81 * to locate its physical store 82 * 83 * If the environment variable vfs.root.mountfrom is a space separated list, 84 * each list element is tried in turn and the root filesystem will be mounted 85 * from the first one that succeeds. 86 * 87 * The environment variable vfs.root.mountfrom.options is a comma delimited 88 * set of string mount options. These mount options must be parseable 89 * by nmount() in the kernel. 90 */ 91 92 static int parse_mount(char **); 93 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 94 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS); 95 static void vfs_mountroot_wait(void); 96 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev); 97 98 /* 99 * The vnode of the system's root (/ in the filesystem, without chroot 100 * active.) 101 */ 102 struct vnode *rootvnode; 103 104 /* 105 * Mount of the system's /dev. 106 */ 107 struct mount *rootdevmp; 108 109 char *rootdevnames[2] = {NULL, NULL}; 110 111 struct mtx root_holds_mtx; 112 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 113 114 static TAILQ_HEAD(, root_hold_token) root_holds = 115 TAILQ_HEAD_INITIALIZER(root_holds); 116 117 enum action { 118 A_CONTINUE, 119 A_PANIC, 120 A_REBOOT, 121 A_RETRY 122 }; 123 124 enum rh_flags { 125 RH_FREE, 126 RH_ALLOC, 127 RH_ARG, 128 }; 129 130 static enum action root_mount_onfail = A_CONTINUE; 131 132 static int root_mount_mddev; 133 static int root_mount_complete; 134 135 /* By default wait up to 3 seconds for devices to appear. */ 136 static int root_mount_timeout = 3; 137 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 138 139 static int root_mount_always_wait = 0; 140 SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN, 141 &root_mount_always_wait, 0, 142 "Wait for root mount holds even if the root device already exists"); 143 144 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold, 145 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 146 NULL, 0, sysctl_vfs_root_mount_hold, "A", 147 "List of root mount hold tokens"); 148 149 static int 150 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS) 151 { 152 struct sbuf sb; 153 struct root_hold_token *h; 154 int error; 155 156 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 157 158 mtx_lock(&root_holds_mtx); 159 TAILQ_FOREACH(h, &root_holds, list) { 160 if (h != TAILQ_FIRST(&root_holds)) 161 sbuf_putc(&sb, ' '); 162 sbuf_printf(&sb, "%s", h->who); 163 } 164 mtx_unlock(&root_holds_mtx); 165 166 error = sbuf_finish(&sb); 167 if (error == 0) 168 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 169 sbuf_delete(&sb); 170 return (error); 171 } 172 173 struct root_hold_token * 174 root_mount_hold(const char *identifier) 175 { 176 struct root_hold_token *h; 177 178 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 179 h->flags = RH_ALLOC; 180 h->who = identifier; 181 mtx_lock(&root_holds_mtx); 182 TSHOLD("root mount"); 183 TAILQ_INSERT_TAIL(&root_holds, h, list); 184 mtx_unlock(&root_holds_mtx); 185 return (h); 186 } 187 188 void 189 root_mount_hold_token(const char *identifier, struct root_hold_token *h) 190 { 191 #ifdef INVARIANTS 192 struct root_hold_token *t; 193 #endif 194 195 h->flags = RH_ARG; 196 h->who = identifier; 197 mtx_lock(&root_holds_mtx); 198 #ifdef INVARIANTS 199 TAILQ_FOREACH(t, &root_holds, list) { 200 if (t == h) { 201 panic("Duplicate mount hold by '%s' on %p", 202 identifier, h); 203 } 204 } 205 #endif 206 TSHOLD("root mount"); 207 TAILQ_INSERT_TAIL(&root_holds, h, list); 208 mtx_unlock(&root_holds_mtx); 209 } 210 211 void 212 root_mount_rel(struct root_hold_token *h) 213 { 214 215 if (h == NULL || h->flags == RH_FREE) 216 return; 217 218 mtx_lock(&root_holds_mtx); 219 TAILQ_REMOVE(&root_holds, h, list); 220 TSRELEASE("root mount"); 221 wakeup(&root_holds); 222 mtx_unlock(&root_holds_mtx); 223 if (h->flags == RH_ALLOC) { 224 free(h, M_DEVBUF); 225 } else 226 h->flags = RH_FREE; 227 } 228 229 int 230 root_mounted(void) 231 { 232 233 /* No mutex is acquired here because int stores are atomic. */ 234 return (root_mount_complete); 235 } 236 237 static void 238 set_rootvnode(void) 239 { 240 241 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 242 panic("set_rootvnode: Cannot find root vnode"); 243 244 VOP_UNLOCK(rootvnode); 245 246 pwd_set_rootvnode(); 247 } 248 249 static int 250 vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 251 { 252 struct vfsoptlist *opts; 253 struct vfsconf *vfsp; 254 struct mount *mp; 255 int error; 256 257 *mpp = NULL; 258 259 if (rootdevmp != NULL) { 260 /* 261 * Already have /dev; this happens during rerooting. 262 */ 263 error = vfs_busy(rootdevmp, 0); 264 if (error != 0) 265 return (error); 266 *mpp = rootdevmp; 267 } else { 268 vfsp = vfs_byname("devfs"); 269 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 270 if (vfsp == NULL) 271 return (ENOENT); 272 273 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 274 275 error = VFS_MOUNT(mp); 276 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 277 if (error) 278 return (error); 279 280 error = VFS_STATFS(mp, &mp->mnt_stat); 281 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error)); 282 if (error) 283 return (error); 284 285 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 286 TAILQ_INIT(opts); 287 mp->mnt_opt = opts; 288 289 mtx_lock(&mountlist_mtx); 290 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 291 mtx_unlock(&mountlist_mtx); 292 293 *mpp = mp; 294 rootdevmp = mp; 295 vfs_op_exit(mp); 296 } 297 298 set_rootvnode(); 299 300 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 301 if (error) 302 printf("kern_symlink /dev -> / returns %d\n", error); 303 304 return (error); 305 } 306 307 static void 308 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 309 { 310 struct nameidata nd; 311 struct mount *mporoot, *mpnroot; 312 struct vnode *vp, *vporoot, *vpdevfs; 313 char *fspath; 314 int error; 315 316 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 317 318 /* Shuffle the mountlist. */ 319 mtx_lock(&mountlist_mtx); 320 mporoot = TAILQ_FIRST(&mountlist); 321 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 322 if (mporoot != mpdevfs) { 323 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 324 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 325 } 326 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 327 mtx_unlock(&mountlist_mtx); 328 329 cache_purgevfs(mporoot); 330 if (mporoot != mpdevfs) 331 cache_purgevfs(mpdevfs); 332 333 if (VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot)) 334 panic("vfs_mountroot_shuffle: Cannot find root vnode"); 335 336 VI_LOCK(vporoot); 337 vporoot->v_iflag &= ~VI_MOUNT; 338 VI_UNLOCK(vporoot); 339 vporoot->v_mountedhere = NULL; 340 mporoot->mnt_flag &= ~MNT_ROOTFS; 341 mporoot->mnt_vnodecovered = NULL; 342 vput(vporoot); 343 344 /* Set up the new rootvnode, and purge the cache */ 345 mpnroot->mnt_vnodecovered = NULL; 346 set_rootvnode(); 347 cache_purgevfs(rootvnode->v_mount); 348 349 if (mporoot != mpdevfs) { 350 /* Remount old root under /.mount or /mnt */ 351 fspath = "/.mount"; 352 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 353 fspath, td); 354 error = namei(&nd); 355 if (error) { 356 NDFREE(&nd, NDF_ONLY_PNBUF); 357 fspath = "/mnt"; 358 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 359 fspath, td); 360 error = namei(&nd); 361 } 362 if (!error) { 363 vp = nd.ni_vp; 364 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 365 if (!error) 366 error = vinvalbuf(vp, V_SAVE, 0, 0); 367 if (!error) { 368 cache_purge(vp); 369 mporoot->mnt_vnodecovered = vp; 370 vp->v_mountedhere = mporoot; 371 strlcpy(mporoot->mnt_stat.f_mntonname, 372 fspath, MNAMELEN); 373 VOP_UNLOCK(vp); 374 } else 375 vput(vp); 376 } 377 NDFREE(&nd, NDF_ONLY_PNBUF); 378 379 if (error) 380 printf("mountroot: unable to remount previous root " 381 "under /.mount or /mnt (error %d)\n", error); 382 } 383 384 /* Remount devfs under /dev */ 385 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 386 error = namei(&nd); 387 if (!error) { 388 vp = nd.ni_vp; 389 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 390 if (!error) 391 error = vinvalbuf(vp, V_SAVE, 0, 0); 392 if (!error) { 393 vpdevfs = mpdevfs->mnt_vnodecovered; 394 if (vpdevfs != NULL) { 395 cache_purge(vpdevfs); 396 vpdevfs->v_mountedhere = NULL; 397 vrele(vpdevfs); 398 } 399 mpdevfs->mnt_vnodecovered = vp; 400 vp->v_mountedhere = mpdevfs; 401 VOP_UNLOCK(vp); 402 } else 403 vput(vp); 404 } 405 if (error) 406 printf("mountroot: unable to remount devfs under /dev " 407 "(error %d)\n", error); 408 NDFREE(&nd, NDF_ONLY_PNBUF); 409 410 if (mporoot == mpdevfs) { 411 vfs_unbusy(mpdevfs); 412 /* Unlink the no longer needed /dev/dev -> / symlink */ 413 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 414 UIO_SYSSPACE, 0, 0); 415 if (error) 416 printf("mountroot: unable to unlink /dev/dev " 417 "(error %d)\n", error); 418 } 419 } 420 421 /* 422 * Configuration parser. 423 */ 424 425 /* Parser character classes. */ 426 #define CC_WHITESPACE -1 427 #define CC_NONWHITESPACE -2 428 429 /* Parse errors. */ 430 #define PE_EOF -1 431 #define PE_EOL -2 432 433 static __inline int 434 parse_peek(char **conf) 435 { 436 437 return (**conf); 438 } 439 440 static __inline void 441 parse_poke(char **conf, int c) 442 { 443 444 **conf = c; 445 } 446 447 static __inline void 448 parse_advance(char **conf) 449 { 450 451 (*conf)++; 452 } 453 454 static int 455 parse_skipto(char **conf, int mc) 456 { 457 int c, match; 458 459 while (1) { 460 c = parse_peek(conf); 461 if (c == 0) 462 return (PE_EOF); 463 switch (mc) { 464 case CC_WHITESPACE: 465 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 466 break; 467 case CC_NONWHITESPACE: 468 if (c == '\n') 469 return (PE_EOL); 470 match = (c != ' ' && c != '\t') ? 1 : 0; 471 break; 472 default: 473 match = (c == mc) ? 1 : 0; 474 break; 475 } 476 if (match) 477 break; 478 parse_advance(conf); 479 } 480 return (0); 481 } 482 483 static int 484 parse_token(char **conf, char **tok) 485 { 486 char *p; 487 size_t len; 488 int error; 489 490 *tok = NULL; 491 error = parse_skipto(conf, CC_NONWHITESPACE); 492 if (error) 493 return (error); 494 p = *conf; 495 error = parse_skipto(conf, CC_WHITESPACE); 496 len = *conf - p; 497 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 498 bcopy(p, *tok, len); 499 return (0); 500 } 501 502 static void 503 parse_dir_ask_printenv(const char *var) 504 { 505 char *val; 506 507 val = kern_getenv(var); 508 if (val != NULL) { 509 printf(" %s=%s\n", var, val); 510 freeenv(val); 511 } 512 } 513 514 static int 515 parse_dir_ask(char **conf) 516 { 517 char name[80]; 518 char *mnt; 519 int error; 520 521 vfs_mountroot_wait(); 522 523 printf("\nLoader variables:\n"); 524 parse_dir_ask_printenv("vfs.root.mountfrom"); 525 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 526 527 printf("\nManual root filesystem specification:\n"); 528 printf(" <fstype>:<device> [options]\n"); 529 printf(" Mount <device> using filesystem <fstype>\n"); 530 printf(" and with the specified (optional) option list.\n"); 531 printf("\n"); 532 printf(" eg. ufs:/dev/da0s1a\n"); 533 printf(" zfs:zroot/ROOT/default\n"); 534 printf(" cd9660:/dev/cd0 ro\n"); 535 printf(" (which is equivalent to: "); 536 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 537 printf("\n"); 538 printf(" ? List valid disk boot devices\n"); 539 printf(" . Yield 1 second (for background tasks)\n"); 540 printf(" <empty line> Abort manual input\n"); 541 542 do { 543 error = EINVAL; 544 printf("\nmountroot> "); 545 cngets(name, sizeof(name), GETS_ECHO); 546 if (name[0] == '\0') 547 break; 548 if (name[0] == '?' && name[1] == '\0') { 549 printf("\nList of GEOM managed disk devices:\n "); 550 g_dev_print(); 551 continue; 552 } 553 if (name[0] == '.' && name[1] == '\0') { 554 pause("rmask", hz); 555 continue; 556 } 557 mnt = name; 558 error = parse_mount(&mnt); 559 if (error == -1) 560 printf("Invalid file system specification.\n"); 561 } while (error != 0); 562 563 return (error); 564 } 565 566 static int 567 parse_dir_md(char **conf) 568 { 569 struct stat sb; 570 struct thread *td; 571 struct md_ioctl *mdio; 572 char *path, *tok; 573 int error, fd, len; 574 575 td = curthread; 576 577 error = parse_token(conf, &tok); 578 if (error) 579 return (error); 580 581 len = strlen(tok); 582 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 583 path = (void *)(mdio + 1); 584 bcopy(tok, path, len); 585 free(tok, M_TEMP); 586 587 /* Get file status. */ 588 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 589 if (error) 590 goto out; 591 592 /* Open /dev/mdctl so that we can attach/detach. */ 593 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 594 O_RDWR, 0); 595 if (error) 596 goto out; 597 598 fd = td->td_retval[0]; 599 mdio->md_version = MDIOVERSION; 600 mdio->md_type = MD_VNODE; 601 602 if (root_mount_mddev != -1) { 603 mdio->md_unit = root_mount_mddev; 604 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 605 /* Ignore errors. We don't care. */ 606 root_mount_mddev = -1; 607 } 608 609 mdio->md_file = (void *)(mdio + 1); 610 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 611 mdio->md_mediasize = sb.st_size; 612 mdio->md_unit = 0; 613 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 614 if (error) 615 goto out; 616 617 if (mdio->md_unit > 9) { 618 printf("rootmount: too many md units\n"); 619 mdio->md_file = NULL; 620 mdio->md_options = 0; 621 mdio->md_mediasize = 0; 622 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 623 /* Ignore errors. We don't care. */ 624 error = ERANGE; 625 goto out; 626 } 627 628 root_mount_mddev = mdio->md_unit; 629 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 630 631 error = kern_close(td, fd); 632 633 out: 634 free(mdio, M_TEMP); 635 return (error); 636 } 637 638 static int 639 parse_dir_onfail(char **conf) 640 { 641 char *action; 642 int error; 643 644 error = parse_token(conf, &action); 645 if (error) 646 return (error); 647 648 if (!strcmp(action, "continue")) 649 root_mount_onfail = A_CONTINUE; 650 else if (!strcmp(action, "panic")) 651 root_mount_onfail = A_PANIC; 652 else if (!strcmp(action, "reboot")) 653 root_mount_onfail = A_REBOOT; 654 else if (!strcmp(action, "retry")) 655 root_mount_onfail = A_RETRY; 656 else { 657 printf("rootmount: %s: unknown action\n", action); 658 error = EINVAL; 659 } 660 661 free(action, M_TEMP); 662 return (0); 663 } 664 665 static int 666 parse_dir_timeout(char **conf) 667 { 668 char *tok, *endtok; 669 long secs; 670 int error; 671 672 error = parse_token(conf, &tok); 673 if (error) 674 return (error); 675 676 secs = strtol(tok, &endtok, 0); 677 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 678 if (!error) 679 root_mount_timeout = secs; 680 free(tok, M_TEMP); 681 return (error); 682 } 683 684 static int 685 parse_directive(char **conf) 686 { 687 char *dir; 688 int error; 689 690 error = parse_token(conf, &dir); 691 if (error) 692 return (error); 693 694 if (strcmp(dir, ".ask") == 0) 695 error = parse_dir_ask(conf); 696 else if (strcmp(dir, ".md") == 0) 697 error = parse_dir_md(conf); 698 else if (strcmp(dir, ".onfail") == 0) 699 error = parse_dir_onfail(conf); 700 else if (strcmp(dir, ".timeout") == 0) 701 error = parse_dir_timeout(conf); 702 else { 703 printf("mountroot: invalid directive `%s'\n", dir); 704 /* Ignore the rest of the line. */ 705 (void)parse_skipto(conf, '\n'); 706 error = EINVAL; 707 } 708 free(dir, M_TEMP); 709 return (error); 710 } 711 712 static int 713 parse_mount_dev_present(const char *dev) 714 { 715 struct nameidata nd; 716 int error; 717 718 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 719 error = namei(&nd); 720 if (!error) 721 vput(nd.ni_vp); 722 NDFREE(&nd, NDF_ONLY_PNBUF); 723 return (error != 0) ? 0 : 1; 724 } 725 726 #define ERRMSGL 255 727 static int 728 parse_mount(char **conf) 729 { 730 char *errmsg; 731 struct mntarg *ma; 732 char *dev, *fs, *opts, *tok; 733 int delay, error, timeout; 734 735 error = parse_token(conf, &tok); 736 if (error) 737 return (error); 738 fs = tok; 739 error = parse_skipto(&tok, ':'); 740 if (error) { 741 free(fs, M_TEMP); 742 return (error); 743 } 744 parse_poke(&tok, '\0'); 745 parse_advance(&tok); 746 dev = tok; 747 748 if (root_mount_mddev != -1) { 749 /* Handle substitution for the md unit number. */ 750 tok = strstr(dev, "md#"); 751 if (tok != NULL) 752 tok[2] = '0' + root_mount_mddev; 753 } 754 755 /* Parse options. */ 756 error = parse_token(conf, &tok); 757 opts = (error == 0) ? tok : NULL; 758 759 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 760 (opts != NULL) ? opts : ""); 761 762 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 763 764 if (vfs_byname(fs) == NULL) { 765 strlcpy(errmsg, "unknown file system", ERRMSGL); 766 error = ENOENT; 767 goto out; 768 } 769 770 error = vfs_mountroot_wait_if_neccessary(fs, dev); 771 if (error != 0) 772 goto out; 773 774 delay = hz / 10; 775 timeout = root_mount_timeout * hz; 776 777 for (;;) { 778 ma = NULL; 779 ma = mount_arg(ma, "fstype", fs, -1); 780 ma = mount_arg(ma, "fspath", "/", -1); 781 ma = mount_arg(ma, "from", dev, -1); 782 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 783 ma = mount_arg(ma, "ro", NULL, 0); 784 ma = parse_mountroot_options(ma, opts); 785 786 error = kernel_mount(ma, MNT_ROOTFS); 787 if (error == 0 || timeout <= 0) 788 break; 789 790 if (root_mount_timeout * hz == timeout || 791 (bootverbose && timeout % hz == 0)) { 792 printf("Mounting from %s:%s failed with error %d; " 793 "retrying for %d more second%s\n", fs, dev, error, 794 timeout / hz, (timeout / hz > 1) ? "s" : ""); 795 } 796 pause("rmretry", delay); 797 timeout -= delay; 798 } 799 out: 800 if (error) { 801 printf("Mounting from %s:%s failed with error %d", 802 fs, dev, error); 803 if (errmsg[0] != '\0') 804 printf(": %s", errmsg); 805 printf(".\n"); 806 } 807 free(fs, M_TEMP); 808 free(errmsg, M_TEMP); 809 if (opts != NULL) 810 free(opts, M_TEMP); 811 /* kernel_mount can return -1 on error. */ 812 return ((error < 0) ? EDOOFUS : error); 813 } 814 #undef ERRMSGL 815 816 static int 817 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 818 { 819 struct mount *mp; 820 char *conf; 821 int error; 822 823 root_mount_mddev = -1; 824 825 retry: 826 conf = sbuf_data(sb); 827 mp = TAILQ_NEXT(mpdevfs, mnt_list); 828 error = (mp == NULL) ? 0 : EDOOFUS; 829 root_mount_onfail = A_CONTINUE; 830 while (mp == NULL) { 831 error = parse_skipto(&conf, CC_NONWHITESPACE); 832 if (error == PE_EOL) { 833 parse_advance(&conf); 834 continue; 835 } 836 if (error < 0) 837 break; 838 switch (parse_peek(&conf)) { 839 case '#': 840 error = parse_skipto(&conf, '\n'); 841 break; 842 case '.': 843 error = parse_directive(&conf); 844 break; 845 default: 846 error = parse_mount(&conf); 847 if (error == -1) { 848 printf("mountroot: invalid file system " 849 "specification.\n"); 850 error = 0; 851 } 852 break; 853 } 854 if (error < 0) 855 break; 856 /* Ignore any trailing garbage on the line. */ 857 if (parse_peek(&conf) != '\n') { 858 printf("mountroot: advancing to next directive...\n"); 859 (void)parse_skipto(&conf, '\n'); 860 } 861 mp = TAILQ_NEXT(mpdevfs, mnt_list); 862 } 863 if (mp != NULL) 864 return (0); 865 866 /* 867 * We failed to mount (a new) root. 868 */ 869 switch (root_mount_onfail) { 870 case A_CONTINUE: 871 break; 872 case A_PANIC: 873 panic("mountroot: unable to (re-)mount root."); 874 /* NOTREACHED */ 875 case A_RETRY: 876 goto retry; 877 case A_REBOOT: 878 kern_reboot(RB_NOSYNC); 879 /* NOTREACHED */ 880 } 881 882 return (error); 883 } 884 885 static void 886 vfs_mountroot_conf0(struct sbuf *sb) 887 { 888 char *s, *tok, *mnt, *opt; 889 int error; 890 891 sbuf_printf(sb, ".onfail panic\n"); 892 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 893 if (boothowto & RB_ASKNAME) 894 sbuf_printf(sb, ".ask\n"); 895 #ifdef ROOTDEVNAME 896 if (boothowto & RB_DFLTROOT) 897 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 898 #endif 899 if (boothowto & RB_CDROM) { 900 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 901 sbuf_printf(sb, ".timeout 0\n"); 902 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 903 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 904 } 905 s = kern_getenv("vfs.root.mountfrom"); 906 if (s != NULL) { 907 opt = kern_getenv("vfs.root.mountfrom.options"); 908 tok = s; 909 error = parse_token(&tok, &mnt); 910 while (!error) { 911 sbuf_printf(sb, "%s %s\n", mnt, 912 (opt != NULL) ? opt : ""); 913 free(mnt, M_TEMP); 914 error = parse_token(&tok, &mnt); 915 } 916 if (opt != NULL) 917 freeenv(opt); 918 freeenv(s); 919 } 920 if (rootdevnames[0] != NULL) 921 sbuf_printf(sb, "%s\n", rootdevnames[0]); 922 if (rootdevnames[1] != NULL) 923 sbuf_printf(sb, "%s\n", rootdevnames[1]); 924 #ifdef ROOTDEVNAME 925 if (!(boothowto & RB_DFLTROOT)) 926 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 927 #endif 928 if (!(boothowto & RB_ASKNAME)) 929 sbuf_printf(sb, ".ask\n"); 930 } 931 932 static int 933 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 934 { 935 static char buf[128]; 936 struct nameidata nd; 937 off_t ofs; 938 ssize_t resid; 939 int error, flags, len; 940 941 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 942 flags = FREAD; 943 error = vn_open(&nd, &flags, 0, NULL); 944 if (error) 945 return (error); 946 947 NDFREE(&nd, NDF_ONLY_PNBUF); 948 ofs = 0; 949 len = sizeof(buf) - 1; 950 while (1) { 951 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 952 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 953 NOCRED, &resid, td); 954 if (error) 955 break; 956 if (resid == len) 957 break; 958 buf[len - resid] = 0; 959 sbuf_printf(sb, "%s", buf); 960 ofs += len - resid; 961 } 962 963 VOP_UNLOCK(nd.ni_vp); 964 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 965 return (error); 966 } 967 968 static void 969 vfs_mountroot_wait(void) 970 { 971 struct root_hold_token *h; 972 struct timeval lastfail; 973 int curfail; 974 975 TSENTER(); 976 977 curfail = 0; 978 while (1) { 979 g_waitidle(); 980 mtx_lock(&root_holds_mtx); 981 if (TAILQ_EMPTY(&root_holds)) { 982 mtx_unlock(&root_holds_mtx); 983 break; 984 } 985 if (ppsratecheck(&lastfail, &curfail, 1)) { 986 printf("Root mount waiting for:"); 987 TAILQ_FOREACH(h, &root_holds, list) 988 printf(" %s", h->who); 989 printf("\n"); 990 } 991 TSWAIT("root mount"); 992 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 993 hz); 994 TSUNWAIT("root mount"); 995 } 996 997 TSEXIT(); 998 } 999 1000 static int 1001 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 1002 { 1003 int delay, timeout; 1004 1005 /* 1006 * In case of ZFS and NFS we don't have a way to wait for 1007 * specific device. Also do the wait if the user forced that 1008 * behaviour by setting vfs.root_mount_always_wait=1. 1009 */ 1010 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 1011 dev[0] == '\0' || root_mount_always_wait != 0) { 1012 vfs_mountroot_wait(); 1013 return (0); 1014 } 1015 1016 /* 1017 * Otherwise, no point in waiting if the device is already there. 1018 * Note that we must wait for GEOM to finish reconfiguring itself, 1019 * eg for geom_part(4) to finish tasting. 1020 */ 1021 g_waitidle(); 1022 if (parse_mount_dev_present(dev)) 1023 return (0); 1024 1025 /* 1026 * No luck. Let's wait. This code looks weird, but it's that way 1027 * to behave exactly as it used to work before. 1028 */ 1029 vfs_mountroot_wait(); 1030 printf("mountroot: waiting for device %s...\n", dev); 1031 delay = hz / 10; 1032 timeout = root_mount_timeout * hz; 1033 do { 1034 pause("rmdev", delay); 1035 timeout -= delay; 1036 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1037 1038 if (timeout <= 0) 1039 return (ENODEV); 1040 1041 return (0); 1042 } 1043 1044 void 1045 vfs_mountroot(void) 1046 { 1047 struct mount *mp; 1048 struct sbuf *sb; 1049 struct thread *td; 1050 time_t timebase; 1051 int error; 1052 1053 mtx_assert(&Giant, MA_NOTOWNED); 1054 1055 TSENTER(); 1056 1057 td = curthread; 1058 1059 sb = sbuf_new_auto(); 1060 vfs_mountroot_conf0(sb); 1061 sbuf_finish(sb); 1062 1063 error = vfs_mountroot_devfs(td, &mp); 1064 while (!error) { 1065 error = vfs_mountroot_parse(sb, mp); 1066 if (!error) { 1067 vfs_mountroot_shuffle(td, mp); 1068 sbuf_clear(sb); 1069 error = vfs_mountroot_readconf(td, sb); 1070 sbuf_finish(sb); 1071 } 1072 } 1073 1074 sbuf_delete(sb); 1075 1076 /* 1077 * Iterate over all currently mounted file systems and use 1078 * the time stamp found to check and/or initialize the RTC. 1079 * Call inittodr() only once and pass it the largest of the 1080 * timestamps we encounter. 1081 */ 1082 timebase = 0; 1083 mtx_lock(&mountlist_mtx); 1084 mp = TAILQ_FIRST(&mountlist); 1085 while (mp != NULL) { 1086 if (mp->mnt_time > timebase) 1087 timebase = mp->mnt_time; 1088 mp = TAILQ_NEXT(mp, mnt_list); 1089 } 1090 mtx_unlock(&mountlist_mtx); 1091 inittodr(timebase); 1092 1093 /* Keep prison0's root in sync with the global rootvnode. */ 1094 mtx_lock(&prison0.pr_mtx); 1095 prison0.pr_root = rootvnode; 1096 vref(prison0.pr_root); 1097 mtx_unlock(&prison0.pr_mtx); 1098 1099 mtx_lock(&root_holds_mtx); 1100 atomic_store_rel_int(&root_mount_complete, 1); 1101 wakeup(&root_mount_complete); 1102 mtx_unlock(&root_holds_mtx); 1103 1104 EVENTHANDLER_INVOKE(mountroot); 1105 1106 TSEXIT(); 1107 } 1108 1109 static struct mntarg * 1110 parse_mountroot_options(struct mntarg *ma, const char *options) 1111 { 1112 char *p; 1113 char *name, *name_arg; 1114 char *val, *val_arg; 1115 char *opts; 1116 1117 if (options == NULL || options[0] == '\0') 1118 return (ma); 1119 1120 p = opts = strdup(options, M_MOUNT); 1121 if (opts == NULL) { 1122 return (ma); 1123 } 1124 1125 while((name = strsep(&p, ",")) != NULL) { 1126 if (name[0] == '\0') 1127 break; 1128 1129 val = strchr(name, '='); 1130 if (val != NULL) { 1131 *val = '\0'; 1132 ++val; 1133 } 1134 if( strcmp(name, "rw") == 0 || 1135 strcmp(name, "noro") == 0) { 1136 /* 1137 * The first time we mount the root file system, 1138 * we need to mount 'ro', so We need to ignore 1139 * 'rw' and 'noro' mount options. 1140 */ 1141 continue; 1142 } 1143 name_arg = strdup(name, M_MOUNT); 1144 val_arg = NULL; 1145 if (val != NULL) 1146 val_arg = strdup(val, M_MOUNT); 1147 1148 ma = mount_arg(ma, name_arg, val_arg, 1149 (val_arg != NULL ? -1 : 0)); 1150 } 1151 free(opts, M_MOUNT); 1152 return (ma); 1153 } 1154