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 #include <sys/param.h> 44 #include <sys/conf.h> 45 #include <sys/cons.h> 46 #include <sys/eventhandler.h> 47 #include <sys/fcntl.h> 48 #include <sys/jail.h> 49 #include <sys/kernel.h> 50 #include <sys/malloc.h> 51 #include <sys/mdioctl.h> 52 #include <sys/mount.h> 53 #include <sys/mutex.h> 54 #include <sys/namei.h> 55 #include <sys/priv.h> 56 #include <sys/proc.h> 57 #include <sys/filedesc.h> 58 #include <sys/reboot.h> 59 #include <sys/sbuf.h> 60 #include <sys/stat.h> 61 #include <sys/syscallsubr.h> 62 #include <sys/sysproto.h> 63 #include <sys/sx.h> 64 #include <sys/sysctl.h> 65 #include <sys/systm.h> 66 #include <sys/vnode.h> 67 68 #include <geom/geom.h> 69 70 /* 71 * The root filesystem is detailed in the kernel environment variable 72 * vfs.root.mountfrom, which is expected to be in the general format 73 * 74 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 75 * vfsname := the name of a VFS known to the kernel and capable 76 * of being mounted as root 77 * path := disk device name or other data used by the filesystem 78 * to locate its physical store 79 * 80 * If the environment variable vfs.root.mountfrom is a space separated list, 81 * each list element is tried in turn and the root filesystem will be mounted 82 * from the first one that succeeds. 83 * 84 * The environment variable vfs.root.mountfrom.options is a comma delimited 85 * set of string mount options. These mount options must be parseable 86 * by nmount() in the kernel. 87 */ 88 89 static int parse_mount(char **); 90 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 91 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS); 92 static void vfs_mountroot_wait(void); 93 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev); 94 95 /* 96 * The vnode of the system's root (/ in the filesystem, without chroot 97 * active.) 98 */ 99 struct vnode *rootvnode; 100 101 /* 102 * Mount of the system's /dev. 103 */ 104 struct mount *rootdevmp; 105 106 char *rootdevnames[2] = {NULL, NULL}; 107 108 struct mtx root_holds_mtx; 109 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 110 111 static TAILQ_HEAD(, root_hold_token) root_holds = 112 TAILQ_HEAD_INITIALIZER(root_holds); 113 114 enum action { 115 A_CONTINUE, 116 A_PANIC, 117 A_REBOOT, 118 A_RETRY 119 }; 120 121 enum rh_flags { 122 RH_FREE, 123 RH_ALLOC, 124 RH_ARG, 125 }; 126 127 static enum action root_mount_onfail = A_CONTINUE; 128 129 static int root_mount_mddev; 130 static int root_mount_complete; 131 132 /* By default wait up to 3 seconds for devices to appear. */ 133 static int root_mount_timeout = 3; 134 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 135 136 static int root_mount_always_wait = 0; 137 SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN, 138 &root_mount_always_wait, 0, 139 "Wait for root mount holds even if the root device already exists"); 140 141 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold, 142 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 143 NULL, 0, sysctl_vfs_root_mount_hold, "A", 144 "List of root mount hold tokens"); 145 146 static int 147 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS) 148 { 149 struct sbuf sb; 150 struct root_hold_token *h; 151 int error; 152 153 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 154 155 mtx_lock(&root_holds_mtx); 156 TAILQ_FOREACH(h, &root_holds, list) { 157 if (h != TAILQ_FIRST(&root_holds)) 158 sbuf_putc(&sb, ' '); 159 sbuf_printf(&sb, "%s", h->who); 160 } 161 mtx_unlock(&root_holds_mtx); 162 163 error = sbuf_finish(&sb); 164 if (error == 0) 165 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 166 sbuf_delete(&sb); 167 return (error); 168 } 169 170 struct root_hold_token * 171 root_mount_hold(const char *identifier) 172 { 173 struct root_hold_token *h; 174 175 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 176 h->flags = RH_ALLOC; 177 h->who = identifier; 178 mtx_lock(&root_holds_mtx); 179 TSHOLD("root mount"); 180 TAILQ_INSERT_TAIL(&root_holds, h, list); 181 mtx_unlock(&root_holds_mtx); 182 return (h); 183 } 184 185 void 186 root_mount_hold_token(const char *identifier, struct root_hold_token *h) 187 { 188 #ifdef INVARIANTS 189 struct root_hold_token *t; 190 #endif 191 192 h->flags = RH_ARG; 193 h->who = identifier; 194 mtx_lock(&root_holds_mtx); 195 #ifdef INVARIANTS 196 TAILQ_FOREACH(t, &root_holds, list) { 197 if (t == h) { 198 panic("Duplicate mount hold by '%s' on %p", 199 identifier, h); 200 } 201 } 202 #endif 203 TSHOLD("root mount"); 204 TAILQ_INSERT_TAIL(&root_holds, h, list); 205 mtx_unlock(&root_holds_mtx); 206 } 207 208 void 209 root_mount_rel(struct root_hold_token *h) 210 { 211 212 if (h == NULL || h->flags == RH_FREE) 213 return; 214 215 mtx_lock(&root_holds_mtx); 216 TAILQ_REMOVE(&root_holds, h, list); 217 TSRELEASE("root mount"); 218 wakeup(&root_holds); 219 mtx_unlock(&root_holds_mtx); 220 if (h->flags == RH_ALLOC) { 221 free(h, M_DEVBUF); 222 } else 223 h->flags = RH_FREE; 224 } 225 226 int 227 root_mounted(void) 228 { 229 230 /* No mutex is acquired here because int stores are atomic. */ 231 return (root_mount_complete); 232 } 233 234 static void 235 set_rootvnode(void) 236 { 237 238 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 239 panic("set_rootvnode: Cannot find root vnode"); 240 241 VOP_UNLOCK(rootvnode); 242 243 pwd_set_rootvnode(); 244 } 245 246 static int 247 vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 248 { 249 struct vfsoptlist *opts; 250 struct vfsconf *vfsp; 251 struct mount *mp; 252 int error; 253 254 *mpp = NULL; 255 256 if (rootdevmp != NULL) { 257 /* 258 * Already have /dev; this happens during rerooting. 259 */ 260 error = vfs_busy(rootdevmp, 0); 261 if (error != 0) 262 return (error); 263 *mpp = rootdevmp; 264 } else { 265 vfsp = vfs_byname("devfs"); 266 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 267 if (vfsp == NULL) 268 return (ENOENT); 269 270 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 271 272 error = VFS_MOUNT(mp); 273 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 274 if (error) 275 return (error); 276 277 error = VFS_STATFS(mp, &mp->mnt_stat); 278 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error)); 279 if (error) 280 return (error); 281 282 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 283 TAILQ_INIT(opts); 284 mp->mnt_opt = opts; 285 286 mtx_lock(&mountlist_mtx); 287 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 288 mtx_unlock(&mountlist_mtx); 289 290 *mpp = mp; 291 rootdevmp = mp; 292 vfs_op_exit(mp); 293 } 294 295 set_rootvnode(); 296 297 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 298 if (error) 299 printf("kern_symlink /dev -> / returns %d\n", error); 300 301 return (error); 302 } 303 304 static void 305 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 306 { 307 struct nameidata nd; 308 struct mount *mporoot, *mpnroot; 309 struct vnode *vp, *vporoot, *vpdevfs; 310 char *fspath; 311 int error; 312 313 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 314 315 /* Shuffle the mountlist. */ 316 mtx_lock(&mountlist_mtx); 317 mporoot = TAILQ_FIRST(&mountlist); 318 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 319 if (mporoot != mpdevfs) { 320 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 321 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 322 } 323 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 324 mtx_unlock(&mountlist_mtx); 325 326 cache_purgevfs(mporoot); 327 if (mporoot != mpdevfs) 328 cache_purgevfs(mpdevfs); 329 330 if (VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot)) 331 panic("vfs_mountroot_shuffle: Cannot find root vnode"); 332 333 VI_LOCK(vporoot); 334 vporoot->v_iflag &= ~VI_MOUNT; 335 vn_irflag_unset_locked(vporoot, VIRF_MOUNTPOINT); 336 vporoot->v_mountedhere = NULL; 337 VI_UNLOCK(vporoot); 338 mporoot->mnt_flag &= ~MNT_ROOTFS; 339 mporoot->mnt_vnodecovered = NULL; 340 vput(vporoot); 341 342 /* Set up the new rootvnode, and purge the cache */ 343 mpnroot->mnt_vnodecovered = NULL; 344 set_rootvnode(); 345 cache_purgevfs(rootvnode->v_mount); 346 347 if (mporoot != mpdevfs) { 348 /* Remount old root under /.mount or /mnt */ 349 fspath = "/.mount"; 350 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath); 351 error = namei(&nd); 352 if (error) { 353 fspath = "/mnt"; 354 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 355 fspath); 356 error = namei(&nd); 357 } 358 if (!error) { 359 NDFREE_PNBUF(&nd); 360 vp = nd.ni_vp; 361 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 362 if (!error) 363 error = vinvalbuf(vp, V_SAVE, 0, 0); 364 if (!error) { 365 cache_purge(vp); 366 VI_LOCK(vp); 367 mporoot->mnt_vnodecovered = vp; 368 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 369 vp->v_mountedhere = mporoot; 370 strlcpy(mporoot->mnt_stat.f_mntonname, 371 fspath, MNAMELEN); 372 VI_UNLOCK(vp); 373 VOP_UNLOCK(vp); 374 } else 375 vput(vp); 376 } 377 378 if (error) 379 printf("mountroot: unable to remount previous root " 380 "under /.mount or /mnt (error %d)\n", error); 381 } 382 383 /* Remount devfs under /dev */ 384 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev"); 385 error = namei(&nd); 386 if (!error) { 387 NDFREE_PNBUF(&nd); 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 VI_LOCK(vpdevfs); 397 vn_irflag_unset_locked(vpdevfs, VIRF_MOUNTPOINT); 398 vpdevfs->v_mountedhere = NULL; 399 VI_UNLOCK(vpdevfs); 400 vrele(vpdevfs); 401 } 402 VI_LOCK(vp); 403 mpdevfs->mnt_vnodecovered = vp; 404 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 405 vp->v_mountedhere = mpdevfs; 406 VI_UNLOCK(vp); 407 VOP_UNLOCK(vp); 408 } else 409 vput(vp); 410 } 411 if (error) 412 printf("mountroot: unable to remount devfs under /dev " 413 "(error %d)\n", error); 414 415 if (mporoot == mpdevfs) { 416 vfs_unbusy(mpdevfs); 417 /* Unlink the no longer needed /dev/dev -> / symlink */ 418 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 419 UIO_SYSSPACE, 0, 0); 420 if (error) 421 printf("mountroot: unable to unlink /dev/dev " 422 "(error %d)\n", error); 423 } 424 } 425 426 /* 427 * Configuration parser. 428 */ 429 430 /* Parser character classes. */ 431 #define CC_WHITESPACE -1 432 #define CC_NONWHITESPACE -2 433 434 /* Parse errors. */ 435 #define PE_EOF -1 436 #define PE_EOL -2 437 438 static __inline int 439 parse_peek(char **conf) 440 { 441 442 return (**conf); 443 } 444 445 static __inline void 446 parse_poke(char **conf, int c) 447 { 448 449 **conf = c; 450 } 451 452 static __inline void 453 parse_advance(char **conf) 454 { 455 456 (*conf)++; 457 } 458 459 static int 460 parse_skipto(char **conf, int mc) 461 { 462 int c, match; 463 464 while (1) { 465 c = parse_peek(conf); 466 if (c == 0) 467 return (PE_EOF); 468 switch (mc) { 469 case CC_WHITESPACE: 470 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 471 break; 472 case CC_NONWHITESPACE: 473 if (c == '\n') 474 return (PE_EOL); 475 match = (c != ' ' && c != '\t') ? 1 : 0; 476 break; 477 default: 478 match = (c == mc) ? 1 : 0; 479 break; 480 } 481 if (match) 482 break; 483 parse_advance(conf); 484 } 485 return (0); 486 } 487 488 static int 489 parse_token(char **conf, char **tok) 490 { 491 char *p; 492 size_t len; 493 int error; 494 495 *tok = NULL; 496 error = parse_skipto(conf, CC_NONWHITESPACE); 497 if (error) 498 return (error); 499 p = *conf; 500 error = parse_skipto(conf, CC_WHITESPACE); 501 len = *conf - p; 502 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 503 bcopy(p, *tok, len); 504 return (0); 505 } 506 507 static void 508 parse_dir_ask_printenv(const char *var) 509 { 510 char *val; 511 512 val = kern_getenv(var); 513 if (val != NULL) { 514 printf(" %s=%s\n", var, val); 515 freeenv(val); 516 } 517 } 518 519 static int 520 parse_dir_ask(char **conf) 521 { 522 char name[80]; 523 char *mnt; 524 int error; 525 526 vfs_mountroot_wait(); 527 528 printf("\nLoader variables:\n"); 529 parse_dir_ask_printenv("vfs.root.mountfrom"); 530 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 531 532 printf("\nManual root filesystem specification:\n"); 533 printf(" <fstype>:<device> [options]\n"); 534 printf(" Mount <device> using filesystem <fstype>\n"); 535 printf(" and with the specified (optional) option list.\n"); 536 printf("\n"); 537 printf(" eg. ufs:/dev/da0s1a\n"); 538 printf(" zfs:zroot/ROOT/default\n"); 539 printf(" cd9660:/dev/cd0 ro\n"); 540 printf(" (which is equivalent to: "); 541 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 542 printf("\n"); 543 printf(" ? List valid disk boot devices\n"); 544 printf(" . Yield 1 second (for background tasks)\n"); 545 printf(" <empty line> Abort manual input\n"); 546 547 do { 548 error = EINVAL; 549 printf("\nmountroot> "); 550 cngets(name, sizeof(name), GETS_ECHO); 551 if (name[0] == '\0') 552 break; 553 if (name[0] == '?' && name[1] == '\0') { 554 printf("\nList of GEOM managed disk devices:\n "); 555 g_dev_print(); 556 continue; 557 } 558 if (name[0] == '.' && name[1] == '\0') { 559 pause("rmask", hz); 560 continue; 561 } 562 mnt = name; 563 error = parse_mount(&mnt); 564 if (error == -1) 565 printf("Invalid file system specification.\n"); 566 } while (error != 0); 567 568 return (error); 569 } 570 571 static int 572 parse_dir_md(char **conf) 573 { 574 struct stat sb; 575 struct thread *td; 576 struct md_ioctl *mdio; 577 char *path, *tok; 578 int error, fd, len; 579 580 td = curthread; 581 fd = -1; 582 583 error = parse_token(conf, &tok); 584 if (error) 585 return (error); 586 587 len = strlen(tok); 588 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 589 path = (void *)(mdio + 1); 590 bcopy(tok, path, len); 591 free(tok, M_TEMP); 592 593 /* Get file status. */ 594 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb); 595 if (error) 596 goto out; 597 598 /* Open /dev/mdctl so that we can attach/detach. */ 599 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 600 O_RDWR, 0); 601 if (error) 602 goto out; 603 604 fd = td->td_retval[0]; 605 mdio->md_version = MDIOVERSION; 606 mdio->md_type = MD_VNODE; 607 608 if (root_mount_mddev != -1) { 609 mdio->md_unit = root_mount_mddev; 610 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 611 /* Ignore errors. We don't care. */ 612 root_mount_mddev = -1; 613 } 614 615 mdio->md_file = (void *)(mdio + 1); 616 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 617 mdio->md_mediasize = sb.st_size; 618 mdio->md_unit = 0; 619 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 620 if (error) 621 goto out; 622 623 if (mdio->md_unit > 9) { 624 printf("rootmount: too many md units\n"); 625 mdio->md_file = NULL; 626 mdio->md_options = 0; 627 mdio->md_mediasize = 0; 628 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 629 /* Ignore errors. We don't care. */ 630 error = ERANGE; 631 goto out; 632 } 633 634 root_mount_mddev = mdio->md_unit; 635 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 636 637 out: 638 if (fd >= 0) 639 (void)kern_close(td, fd); 640 free(mdio, M_TEMP); 641 return (error); 642 } 643 644 static int 645 parse_dir_onfail(char **conf) 646 { 647 char *action; 648 int error; 649 650 error = parse_token(conf, &action); 651 if (error) 652 return (error); 653 654 if (!strcmp(action, "continue")) 655 root_mount_onfail = A_CONTINUE; 656 else if (!strcmp(action, "panic")) 657 root_mount_onfail = A_PANIC; 658 else if (!strcmp(action, "reboot")) 659 root_mount_onfail = A_REBOOT; 660 else if (!strcmp(action, "retry")) 661 root_mount_onfail = A_RETRY; 662 else { 663 printf("rootmount: %s: unknown action\n", action); 664 error = EINVAL; 665 } 666 667 free(action, M_TEMP); 668 return (0); 669 } 670 671 static int 672 parse_dir_timeout(char **conf) 673 { 674 char *tok, *endtok; 675 long secs; 676 int error; 677 678 error = parse_token(conf, &tok); 679 if (error) 680 return (error); 681 682 secs = strtol(tok, &endtok, 0); 683 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 684 if (!error) 685 root_mount_timeout = secs; 686 free(tok, M_TEMP); 687 return (error); 688 } 689 690 static int 691 parse_directive(char **conf) 692 { 693 char *dir; 694 int error; 695 696 error = parse_token(conf, &dir); 697 if (error) 698 return (error); 699 700 if (strcmp(dir, ".ask") == 0) 701 error = parse_dir_ask(conf); 702 else if (strcmp(dir, ".md") == 0) 703 error = parse_dir_md(conf); 704 else if (strcmp(dir, ".onfail") == 0) 705 error = parse_dir_onfail(conf); 706 else if (strcmp(dir, ".timeout") == 0) 707 error = parse_dir_timeout(conf); 708 else { 709 printf("mountroot: invalid directive `%s'\n", dir); 710 /* Ignore the rest of the line. */ 711 (void)parse_skipto(conf, '\n'); 712 error = EINVAL; 713 } 714 free(dir, M_TEMP); 715 return (error); 716 } 717 718 static bool 719 parse_mount_dev_present(const char *dev) 720 { 721 struct nameidata nd; 722 int error; 723 724 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, dev); 725 error = namei(&nd); 726 if (error != 0) 727 return (false); 728 vrele(nd.ni_vp); 729 NDFREE_PNBUF(&nd); 730 return (true); 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 || error == EILSEQ || 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"); 949 flags = FREAD; 950 error = vn_open(&nd, &flags, 0, NULL); 951 if (error) 952 return (error); 953 954 NDFREE_PNBUF(&nd); 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 thread *td; 980 struct timeval lastfail; 981 int curfail; 982 983 TSENTER(); 984 985 curfail = 0; 986 lastfail.tv_sec = 0; 987 eventratecheck(&lastfail, &curfail, 1); 988 td = curthread; 989 while (1) { 990 g_waitidle(td); 991 mtx_lock(&root_holds_mtx); 992 if (TAILQ_EMPTY(&root_holds)) { 993 mtx_unlock(&root_holds_mtx); 994 break; 995 } 996 if (eventratecheck(&lastfail, &curfail, 1)) { 997 printf("Root mount waiting for:"); 998 TAILQ_FOREACH(h, &root_holds, list) 999 printf(" %s", h->who); 1000 printf("\n"); 1001 } 1002 TSWAIT("root mount"); 1003 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 1004 hz); 1005 TSUNWAIT("root mount"); 1006 } 1007 g_waitidle(td); 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(curthread); 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 if (parse_mount_dev_present(dev)) 1043 return (0); 1044 printf("mountroot: waiting for device %s...\n", dev); 1045 delay = hz / 10; 1046 timeout = root_mount_timeout * hz; 1047 do { 1048 pause("rmdev", delay); 1049 timeout -= delay; 1050 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1051 1052 if (timeout <= 0) 1053 return (ENODEV); 1054 1055 return (0); 1056 } 1057 1058 void 1059 vfs_mountroot(void) 1060 { 1061 struct mount *mp; 1062 struct sbuf *sb; 1063 struct thread *td; 1064 time_t timebase; 1065 int error; 1066 1067 mtx_assert(&Giant, MA_NOTOWNED); 1068 1069 TSENTER(); 1070 1071 td = curthread; 1072 1073 sb = sbuf_new_auto(); 1074 vfs_mountroot_conf0(sb); 1075 sbuf_finish(sb); 1076 1077 error = vfs_mountroot_devfs(td, &mp); 1078 while (!error) { 1079 error = vfs_mountroot_parse(sb, mp); 1080 if (!error) { 1081 vfs_mountroot_shuffle(td, mp); 1082 sbuf_clear(sb); 1083 error = vfs_mountroot_readconf(td, sb); 1084 sbuf_finish(sb); 1085 } 1086 } 1087 1088 sbuf_delete(sb); 1089 1090 /* 1091 * Iterate over all currently mounted file systems and use 1092 * the time stamp found to check and/or initialize the RTC. 1093 * Call inittodr() only once and pass it the largest of the 1094 * timestamps we encounter. 1095 */ 1096 timebase = 0; 1097 mtx_lock(&mountlist_mtx); 1098 mp = TAILQ_FIRST(&mountlist); 1099 while (mp != NULL) { 1100 if (mp->mnt_time > timebase) 1101 timebase = mp->mnt_time; 1102 mp = TAILQ_NEXT(mp, mnt_list); 1103 } 1104 mtx_unlock(&mountlist_mtx); 1105 inittodr(timebase); 1106 1107 /* Keep prison0's root in sync with the global rootvnode. */ 1108 mtx_lock(&prison0.pr_mtx); 1109 prison0.pr_root = rootvnode; 1110 vref(prison0.pr_root); 1111 mtx_unlock(&prison0.pr_mtx); 1112 1113 mtx_lock(&root_holds_mtx); 1114 atomic_store_rel_int(&root_mount_complete, 1); 1115 wakeup(&root_mount_complete); 1116 mtx_unlock(&root_holds_mtx); 1117 1118 EVENTHANDLER_INVOKE(mountroot); 1119 1120 TSEXIT(); 1121 } 1122 1123 static struct mntarg * 1124 parse_mountroot_options(struct mntarg *ma, const char *options) 1125 { 1126 char *p; 1127 char *name, *name_arg; 1128 char *val, *val_arg; 1129 char *opts; 1130 1131 if (options == NULL || options[0] == '\0') 1132 return (ma); 1133 1134 p = opts = strdup(options, M_MOUNT); 1135 if (opts == NULL) { 1136 return (ma); 1137 } 1138 1139 while((name = strsep(&p, ",")) != NULL) { 1140 if (name[0] == '\0') 1141 break; 1142 1143 val = strchr(name, '='); 1144 if (val != NULL) { 1145 *val = '\0'; 1146 ++val; 1147 } 1148 if (strcmp(name, "rw") == 0 || strcmp(name, "noro") == 0) { 1149 /* 1150 * The first time we mount the root file system, 1151 * we need to mount 'ro', so We need to ignore 1152 * 'rw' and 'noro' mount options. 1153 */ 1154 continue; 1155 } 1156 name_arg = strdup(name, M_MOUNT); 1157 val_arg = NULL; 1158 if (val != NULL) 1159 val_arg = strdup(val, M_MOUNT); 1160 1161 ma = mount_arg(ma, name_arg, val_arg, 1162 (val_arg != NULL ? -1 : 0)); 1163 } 1164 free(opts, M_MOUNT); 1165 return (ma); 1166 } 1167