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