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 vn_irflag_unset_locked(vporoot, VIRF_MOUNTPOINT); 339 vporoot->v_mountedhere = NULL; 340 VI_UNLOCK(vporoot); 341 mporoot->mnt_flag &= ~MNT_ROOTFS; 342 mporoot->mnt_vnodecovered = NULL; 343 vput(vporoot); 344 345 /* Set up the new rootvnode, and purge the cache */ 346 mpnroot->mnt_vnodecovered = NULL; 347 set_rootvnode(); 348 cache_purgevfs(rootvnode->v_mount); 349 350 if (mporoot != mpdevfs) { 351 /* Remount old root under /.mount or /mnt */ 352 fspath = "/.mount"; 353 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 354 fspath, td); 355 error = namei(&nd); 356 if (error) { 357 NDFREE(&nd, NDF_ONLY_PNBUF); 358 fspath = "/mnt"; 359 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 360 fspath, td); 361 error = namei(&nd); 362 } 363 if (!error) { 364 vp = nd.ni_vp; 365 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 366 if (!error) 367 error = vinvalbuf(vp, V_SAVE, 0, 0); 368 if (!error) { 369 cache_purge(vp); 370 VI_LOCK(vp); 371 mporoot->mnt_vnodecovered = vp; 372 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 373 vp->v_mountedhere = mporoot; 374 strlcpy(mporoot->mnt_stat.f_mntonname, 375 fspath, MNAMELEN); 376 VI_UNLOCK(vp); 377 VOP_UNLOCK(vp); 378 } else 379 vput(vp); 380 } 381 NDFREE(&nd, NDF_ONLY_PNBUF); 382 383 if (error) 384 printf("mountroot: unable to remount previous root " 385 "under /.mount or /mnt (error %d)\n", error); 386 } 387 388 /* Remount devfs under /dev */ 389 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 390 error = namei(&nd); 391 if (!error) { 392 vp = nd.ni_vp; 393 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 394 if (!error) 395 error = vinvalbuf(vp, V_SAVE, 0, 0); 396 if (!error) { 397 vpdevfs = mpdevfs->mnt_vnodecovered; 398 if (vpdevfs != NULL) { 399 cache_purge(vpdevfs); 400 VI_LOCK(vpdevfs); 401 vn_irflag_unset_locked(vpdevfs, VIRF_MOUNTPOINT); 402 vpdevfs->v_mountedhere = NULL; 403 VI_UNLOCK(vpdevfs); 404 vrele(vpdevfs); 405 } 406 VI_LOCK(vp); 407 mpdevfs->mnt_vnodecovered = vp; 408 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 409 vp->v_mountedhere = mpdevfs; 410 VI_UNLOCK(vp); 411 VOP_UNLOCK(vp); 412 } else 413 vput(vp); 414 } 415 if (error) 416 printf("mountroot: unable to remount devfs under /dev " 417 "(error %d)\n", error); 418 NDFREE(&nd, NDF_ONLY_PNBUF); 419 420 if (mporoot == mpdevfs) { 421 vfs_unbusy(mpdevfs); 422 /* Unlink the no longer needed /dev/dev -> / symlink */ 423 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 424 UIO_SYSSPACE, 0, 0); 425 if (error) 426 printf("mountroot: unable to unlink /dev/dev " 427 "(error %d)\n", error); 428 } 429 } 430 431 /* 432 * Configuration parser. 433 */ 434 435 /* Parser character classes. */ 436 #define CC_WHITESPACE -1 437 #define CC_NONWHITESPACE -2 438 439 /* Parse errors. */ 440 #define PE_EOF -1 441 #define PE_EOL -2 442 443 static __inline int 444 parse_peek(char **conf) 445 { 446 447 return (**conf); 448 } 449 450 static __inline void 451 parse_poke(char **conf, int c) 452 { 453 454 **conf = c; 455 } 456 457 static __inline void 458 parse_advance(char **conf) 459 { 460 461 (*conf)++; 462 } 463 464 static int 465 parse_skipto(char **conf, int mc) 466 { 467 int c, match; 468 469 while (1) { 470 c = parse_peek(conf); 471 if (c == 0) 472 return (PE_EOF); 473 switch (mc) { 474 case CC_WHITESPACE: 475 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 476 break; 477 case CC_NONWHITESPACE: 478 if (c == '\n') 479 return (PE_EOL); 480 match = (c != ' ' && c != '\t') ? 1 : 0; 481 break; 482 default: 483 match = (c == mc) ? 1 : 0; 484 break; 485 } 486 if (match) 487 break; 488 parse_advance(conf); 489 } 490 return (0); 491 } 492 493 static int 494 parse_token(char **conf, char **tok) 495 { 496 char *p; 497 size_t len; 498 int error; 499 500 *tok = NULL; 501 error = parse_skipto(conf, CC_NONWHITESPACE); 502 if (error) 503 return (error); 504 p = *conf; 505 error = parse_skipto(conf, CC_WHITESPACE); 506 len = *conf - p; 507 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 508 bcopy(p, *tok, len); 509 return (0); 510 } 511 512 static void 513 parse_dir_ask_printenv(const char *var) 514 { 515 char *val; 516 517 val = kern_getenv(var); 518 if (val != NULL) { 519 printf(" %s=%s\n", var, val); 520 freeenv(val); 521 } 522 } 523 524 static int 525 parse_dir_ask(char **conf) 526 { 527 char name[80]; 528 char *mnt; 529 int error; 530 531 vfs_mountroot_wait(); 532 533 printf("\nLoader variables:\n"); 534 parse_dir_ask_printenv("vfs.root.mountfrom"); 535 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 536 537 printf("\nManual root filesystem specification:\n"); 538 printf(" <fstype>:<device> [options]\n"); 539 printf(" Mount <device> using filesystem <fstype>\n"); 540 printf(" and with the specified (optional) option list.\n"); 541 printf("\n"); 542 printf(" eg. ufs:/dev/da0s1a\n"); 543 printf(" zfs:zroot/ROOT/default\n"); 544 printf(" cd9660:/dev/cd0 ro\n"); 545 printf(" (which is equivalent to: "); 546 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 547 printf("\n"); 548 printf(" ? List valid disk boot devices\n"); 549 printf(" . Yield 1 second (for background tasks)\n"); 550 printf(" <empty line> Abort manual input\n"); 551 552 do { 553 error = EINVAL; 554 printf("\nmountroot> "); 555 cngets(name, sizeof(name), GETS_ECHO); 556 if (name[0] == '\0') 557 break; 558 if (name[0] == '?' && name[1] == '\0') { 559 printf("\nList of GEOM managed disk devices:\n "); 560 g_dev_print(); 561 continue; 562 } 563 if (name[0] == '.' && name[1] == '\0') { 564 pause("rmask", hz); 565 continue; 566 } 567 mnt = name; 568 error = parse_mount(&mnt); 569 if (error == -1) 570 printf("Invalid file system specification.\n"); 571 } while (error != 0); 572 573 return (error); 574 } 575 576 static int 577 parse_dir_md(char **conf) 578 { 579 struct stat sb; 580 struct thread *td; 581 struct md_ioctl *mdio; 582 char *path, *tok; 583 int error, fd, len; 584 585 td = curthread; 586 fd = -1; 587 588 error = parse_token(conf, &tok); 589 if (error) 590 return (error); 591 592 len = strlen(tok); 593 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 594 path = (void *)(mdio + 1); 595 bcopy(tok, path, len); 596 free(tok, M_TEMP); 597 598 /* Get file status. */ 599 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 600 if (error) 601 goto out; 602 603 /* Open /dev/mdctl so that we can attach/detach. */ 604 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 605 O_RDWR, 0); 606 if (error) 607 goto out; 608 609 fd = td->td_retval[0]; 610 mdio->md_version = MDIOVERSION; 611 mdio->md_type = MD_VNODE; 612 613 if (root_mount_mddev != -1) { 614 mdio->md_unit = root_mount_mddev; 615 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 616 /* Ignore errors. We don't care. */ 617 root_mount_mddev = -1; 618 } 619 620 mdio->md_file = (void *)(mdio + 1); 621 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 622 mdio->md_mediasize = sb.st_size; 623 mdio->md_unit = 0; 624 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 625 if (error) 626 goto out; 627 628 if (mdio->md_unit > 9) { 629 printf("rootmount: too many md units\n"); 630 mdio->md_file = NULL; 631 mdio->md_options = 0; 632 mdio->md_mediasize = 0; 633 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 634 /* Ignore errors. We don't care. */ 635 error = ERANGE; 636 goto out; 637 } 638 639 root_mount_mddev = mdio->md_unit; 640 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 641 642 out: 643 if (fd >= 0) 644 (void)kern_close(td, fd); 645 free(mdio, M_TEMP); 646 return (error); 647 } 648 649 static int 650 parse_dir_onfail(char **conf) 651 { 652 char *action; 653 int error; 654 655 error = parse_token(conf, &action); 656 if (error) 657 return (error); 658 659 if (!strcmp(action, "continue")) 660 root_mount_onfail = A_CONTINUE; 661 else if (!strcmp(action, "panic")) 662 root_mount_onfail = A_PANIC; 663 else if (!strcmp(action, "reboot")) 664 root_mount_onfail = A_REBOOT; 665 else if (!strcmp(action, "retry")) 666 root_mount_onfail = A_RETRY; 667 else { 668 printf("rootmount: %s: unknown action\n", action); 669 error = EINVAL; 670 } 671 672 free(action, M_TEMP); 673 return (0); 674 } 675 676 static int 677 parse_dir_timeout(char **conf) 678 { 679 char *tok, *endtok; 680 long secs; 681 int error; 682 683 error = parse_token(conf, &tok); 684 if (error) 685 return (error); 686 687 secs = strtol(tok, &endtok, 0); 688 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 689 if (!error) 690 root_mount_timeout = secs; 691 free(tok, M_TEMP); 692 return (error); 693 } 694 695 static int 696 parse_directive(char **conf) 697 { 698 char *dir; 699 int error; 700 701 error = parse_token(conf, &dir); 702 if (error) 703 return (error); 704 705 if (strcmp(dir, ".ask") == 0) 706 error = parse_dir_ask(conf); 707 else if (strcmp(dir, ".md") == 0) 708 error = parse_dir_md(conf); 709 else if (strcmp(dir, ".onfail") == 0) 710 error = parse_dir_onfail(conf); 711 else if (strcmp(dir, ".timeout") == 0) 712 error = parse_dir_timeout(conf); 713 else { 714 printf("mountroot: invalid directive `%s'\n", dir); 715 /* Ignore the rest of the line. */ 716 (void)parse_skipto(conf, '\n'); 717 error = EINVAL; 718 } 719 free(dir, M_TEMP); 720 return (error); 721 } 722 723 static int 724 parse_mount_dev_present(const char *dev) 725 { 726 struct nameidata nd; 727 int error; 728 729 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 730 error = namei(&nd); 731 if (!error) 732 vput(nd.ni_vp); 733 NDFREE(&nd, NDF_ONLY_PNBUF); 734 return (error != 0) ? 0 : 1; 735 } 736 737 #define ERRMSGL 255 738 static int 739 parse_mount(char **conf) 740 { 741 char *errmsg; 742 struct mntarg *ma; 743 char *dev, *fs, *opts, *tok; 744 int delay, error, timeout; 745 746 error = parse_token(conf, &tok); 747 if (error) 748 return (error); 749 fs = tok; 750 error = parse_skipto(&tok, ':'); 751 if (error) { 752 free(fs, M_TEMP); 753 return (error); 754 } 755 parse_poke(&tok, '\0'); 756 parse_advance(&tok); 757 dev = tok; 758 759 if (root_mount_mddev != -1) { 760 /* Handle substitution for the md unit number. */ 761 tok = strstr(dev, "md#"); 762 if (tok != NULL) 763 tok[2] = '0' + root_mount_mddev; 764 } 765 766 /* Parse options. */ 767 error = parse_token(conf, &tok); 768 opts = (error == 0) ? tok : NULL; 769 770 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 771 (opts != NULL) ? opts : ""); 772 773 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 774 775 if (vfs_byname(fs) == NULL) { 776 strlcpy(errmsg, "unknown file system", ERRMSGL); 777 error = ENOENT; 778 goto out; 779 } 780 781 error = vfs_mountroot_wait_if_neccessary(fs, dev); 782 if (error != 0) 783 goto out; 784 785 delay = hz / 10; 786 timeout = root_mount_timeout * hz; 787 788 for (;;) { 789 ma = NULL; 790 ma = mount_arg(ma, "fstype", fs, -1); 791 ma = mount_arg(ma, "fspath", "/", -1); 792 ma = mount_arg(ma, "from", dev, -1); 793 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 794 ma = mount_arg(ma, "ro", NULL, 0); 795 ma = parse_mountroot_options(ma, opts); 796 797 error = kernel_mount(ma, MNT_ROOTFS); 798 if (error == 0 || timeout <= 0) 799 break; 800 801 if (root_mount_timeout * hz == timeout || 802 (bootverbose && timeout % hz == 0)) { 803 printf("Mounting from %s:%s failed with error %d; " 804 "retrying for %d more second%s\n", fs, dev, error, 805 timeout / hz, (timeout / hz > 1) ? "s" : ""); 806 } 807 pause("rmretry", delay); 808 timeout -= delay; 809 } 810 out: 811 if (error) { 812 printf("Mounting from %s:%s failed with error %d", 813 fs, dev, error); 814 if (errmsg[0] != '\0') 815 printf(": %s", errmsg); 816 printf(".\n"); 817 } 818 free(fs, M_TEMP); 819 free(errmsg, M_TEMP); 820 if (opts != NULL) 821 free(opts, M_TEMP); 822 /* kernel_mount can return -1 on error. */ 823 return ((error < 0) ? EDOOFUS : error); 824 } 825 #undef ERRMSGL 826 827 static int 828 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 829 { 830 struct mount *mp; 831 char *conf; 832 int error; 833 834 root_mount_mddev = -1; 835 836 retry: 837 conf = sbuf_data(sb); 838 mp = TAILQ_NEXT(mpdevfs, mnt_list); 839 error = (mp == NULL) ? 0 : EDOOFUS; 840 root_mount_onfail = A_CONTINUE; 841 while (mp == NULL) { 842 error = parse_skipto(&conf, CC_NONWHITESPACE); 843 if (error == PE_EOL) { 844 parse_advance(&conf); 845 continue; 846 } 847 if (error < 0) 848 break; 849 switch (parse_peek(&conf)) { 850 case '#': 851 error = parse_skipto(&conf, '\n'); 852 break; 853 case '.': 854 error = parse_directive(&conf); 855 break; 856 default: 857 error = parse_mount(&conf); 858 if (error == -1) { 859 printf("mountroot: invalid file system " 860 "specification.\n"); 861 error = 0; 862 } 863 break; 864 } 865 if (error < 0) 866 break; 867 /* Ignore any trailing garbage on the line. */ 868 if (parse_peek(&conf) != '\n') { 869 printf("mountroot: advancing to next directive...\n"); 870 (void)parse_skipto(&conf, '\n'); 871 } 872 mp = TAILQ_NEXT(mpdevfs, mnt_list); 873 } 874 if (mp != NULL) 875 return (0); 876 877 /* 878 * We failed to mount (a new) root. 879 */ 880 switch (root_mount_onfail) { 881 case A_CONTINUE: 882 break; 883 case A_PANIC: 884 panic("mountroot: unable to (re-)mount root."); 885 /* NOTREACHED */ 886 case A_RETRY: 887 goto retry; 888 case A_REBOOT: 889 kern_reboot(RB_NOSYNC); 890 /* NOTREACHED */ 891 } 892 893 return (error); 894 } 895 896 static void 897 vfs_mountroot_conf0(struct sbuf *sb) 898 { 899 char *s, *tok, *mnt, *opt; 900 int error; 901 902 sbuf_printf(sb, ".onfail panic\n"); 903 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 904 if (boothowto & RB_ASKNAME) 905 sbuf_printf(sb, ".ask\n"); 906 #ifdef ROOTDEVNAME 907 if (boothowto & RB_DFLTROOT) 908 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 909 #endif 910 if (boothowto & RB_CDROM) { 911 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 912 sbuf_printf(sb, ".timeout 0\n"); 913 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 914 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 915 } 916 s = kern_getenv("vfs.root.mountfrom"); 917 if (s != NULL) { 918 opt = kern_getenv("vfs.root.mountfrom.options"); 919 tok = s; 920 error = parse_token(&tok, &mnt); 921 while (!error) { 922 sbuf_printf(sb, "%s %s\n", mnt, 923 (opt != NULL) ? opt : ""); 924 free(mnt, M_TEMP); 925 error = parse_token(&tok, &mnt); 926 } 927 if (opt != NULL) 928 freeenv(opt); 929 freeenv(s); 930 } 931 if (rootdevnames[0] != NULL) 932 sbuf_printf(sb, "%s\n", rootdevnames[0]); 933 if (rootdevnames[1] != NULL) 934 sbuf_printf(sb, "%s\n", rootdevnames[1]); 935 #ifdef ROOTDEVNAME 936 if (!(boothowto & RB_DFLTROOT)) 937 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 938 #endif 939 if (!(boothowto & RB_ASKNAME)) 940 sbuf_printf(sb, ".ask\n"); 941 } 942 943 static int 944 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 945 { 946 static char buf[128]; 947 struct nameidata nd; 948 off_t ofs; 949 ssize_t resid; 950 int error, flags, len; 951 952 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 953 flags = FREAD; 954 error = vn_open(&nd, &flags, 0, NULL); 955 if (error) 956 return (error); 957 958 NDFREE(&nd, NDF_ONLY_PNBUF); 959 ofs = 0; 960 len = sizeof(buf) - 1; 961 while (1) { 962 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 963 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 964 NOCRED, &resid, td); 965 if (error) 966 break; 967 if (resid == len) 968 break; 969 buf[len - resid] = 0; 970 sbuf_printf(sb, "%s", buf); 971 ofs += len - resid; 972 } 973 974 VOP_UNLOCK(nd.ni_vp); 975 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 976 return (error); 977 } 978 979 static void 980 vfs_mountroot_wait(void) 981 { 982 struct root_hold_token *h; 983 struct timeval lastfail; 984 int curfail; 985 986 TSENTER(); 987 988 curfail = 0; 989 lastfail.tv_sec = 0; 990 while (1) { 991 g_waitidle(); 992 mtx_lock(&root_holds_mtx); 993 if (TAILQ_EMPTY(&root_holds)) { 994 mtx_unlock(&root_holds_mtx); 995 break; 996 } 997 if (ppsratecheck(&lastfail, &curfail, 1)) { 998 printf("Root mount waiting for:"); 999 TAILQ_FOREACH(h, &root_holds, list) 1000 printf(" %s", h->who); 1001 printf("\n"); 1002 } 1003 TSWAIT("root mount"); 1004 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 1005 hz); 1006 TSUNWAIT("root mount"); 1007 } 1008 1009 TSEXIT(); 1010 } 1011 1012 static int 1013 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 1014 { 1015 int delay, timeout; 1016 1017 /* 1018 * In case of ZFS and NFS we don't have a way to wait for 1019 * specific device. Also do the wait if the user forced that 1020 * behaviour by setting vfs.root_mount_always_wait=1. 1021 */ 1022 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 1023 dev[0] == '\0' || root_mount_always_wait != 0) { 1024 vfs_mountroot_wait(); 1025 return (0); 1026 } 1027 1028 /* 1029 * Otherwise, no point in waiting if the device is already there. 1030 * Note that we must wait for GEOM to finish reconfiguring itself, 1031 * eg for geom_part(4) to finish tasting. 1032 */ 1033 g_waitidle(); 1034 if (parse_mount_dev_present(dev)) 1035 return (0); 1036 1037 /* 1038 * No luck. Let's wait. This code looks weird, but it's that way 1039 * to behave exactly as it used to work before. 1040 */ 1041 vfs_mountroot_wait(); 1042 printf("mountroot: waiting for device %s...\n", dev); 1043 delay = hz / 10; 1044 timeout = root_mount_timeout * hz; 1045 do { 1046 pause("rmdev", delay); 1047 timeout -= delay; 1048 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1049 1050 if (timeout <= 0) 1051 return (ENODEV); 1052 1053 return (0); 1054 } 1055 1056 void 1057 vfs_mountroot(void) 1058 { 1059 struct mount *mp; 1060 struct sbuf *sb; 1061 struct thread *td; 1062 time_t timebase; 1063 int error; 1064 1065 mtx_assert(&Giant, MA_NOTOWNED); 1066 1067 TSENTER(); 1068 1069 td = curthread; 1070 1071 sb = sbuf_new_auto(); 1072 vfs_mountroot_conf0(sb); 1073 sbuf_finish(sb); 1074 1075 error = vfs_mountroot_devfs(td, &mp); 1076 while (!error) { 1077 error = vfs_mountroot_parse(sb, mp); 1078 if (!error) { 1079 vfs_mountroot_shuffle(td, mp); 1080 sbuf_clear(sb); 1081 error = vfs_mountroot_readconf(td, sb); 1082 sbuf_finish(sb); 1083 } 1084 } 1085 1086 sbuf_delete(sb); 1087 1088 /* 1089 * Iterate over all currently mounted file systems and use 1090 * the time stamp found to check and/or initialize the RTC. 1091 * Call inittodr() only once and pass it the largest of the 1092 * timestamps we encounter. 1093 */ 1094 timebase = 0; 1095 mtx_lock(&mountlist_mtx); 1096 mp = TAILQ_FIRST(&mountlist); 1097 while (mp != NULL) { 1098 if (mp->mnt_time > timebase) 1099 timebase = mp->mnt_time; 1100 mp = TAILQ_NEXT(mp, mnt_list); 1101 } 1102 mtx_unlock(&mountlist_mtx); 1103 inittodr(timebase); 1104 1105 /* Keep prison0's root in sync with the global rootvnode. */ 1106 mtx_lock(&prison0.pr_mtx); 1107 prison0.pr_root = rootvnode; 1108 vref(prison0.pr_root); 1109 mtx_unlock(&prison0.pr_mtx); 1110 1111 mtx_lock(&root_holds_mtx); 1112 atomic_store_rel_int(&root_mount_complete, 1); 1113 wakeup(&root_mount_complete); 1114 mtx_unlock(&root_holds_mtx); 1115 1116 EVENTHANDLER_INVOKE(mountroot); 1117 1118 TSEXIT(); 1119 } 1120 1121 static struct mntarg * 1122 parse_mountroot_options(struct mntarg *ma, const char *options) 1123 { 1124 char *p; 1125 char *name, *name_arg; 1126 char *val, *val_arg; 1127 char *opts; 1128 1129 if (options == NULL || options[0] == '\0') 1130 return (ma); 1131 1132 p = opts = strdup(options, M_MOUNT); 1133 if (opts == NULL) { 1134 return (ma); 1135 } 1136 1137 while((name = strsep(&p, ",")) != NULL) { 1138 if (name[0] == '\0') 1139 break; 1140 1141 val = strchr(name, '='); 1142 if (val != NULL) { 1143 *val = '\0'; 1144 ++val; 1145 } 1146 if (strcmp(name, "rw") == 0 || strcmp(name, "noro") == 0) { 1147 /* 1148 * The first time we mount the root file system, 1149 * we need to mount 'ro', so We need to ignore 1150 * 'rw' and 'noro' mount options. 1151 */ 1152 continue; 1153 } 1154 name_arg = strdup(name, M_MOUNT); 1155 val_arg = NULL; 1156 if (val != NULL) 1157 val_arg = strdup(val, M_MOUNT); 1158 1159 ma = mount_arg(ma, name_arg, val_arg, 1160 (val_arg != NULL ? -1 : 0)); 1161 } 1162 free(opts, M_MOUNT); 1163 return (ma); 1164 } 1165