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/param.h> 43 #include <sys/conf.h> 44 #include <sys/cons.h> 45 #include <sys/eventhandler.h> 46 #include <sys/fcntl.h> 47 #include <sys/jail.h> 48 #include <sys/kernel.h> 49 #include <sys/malloc.h> 50 #include <sys/mdioctl.h> 51 #include <sys/mount.h> 52 #include <sys/mutex.h> 53 #include <sys/namei.h> 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/filedesc.h> 57 #include <sys/reboot.h> 58 #include <sys/sbuf.h> 59 #include <sys/stat.h> 60 #include <sys/syscallsubr.h> 61 #include <sys/sysproto.h> 62 #include <sys/sx.h> 63 #include <sys/sysctl.h> 64 #include <sys/systm.h> 65 #include <sys/vnode.h> 66 67 #include <geom/geom.h> 68 69 /* 70 * The root filesystem is detailed in the kernel environment variable 71 * vfs.root.mountfrom, which is expected to be in the general format 72 * 73 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 74 * vfsname := the name of a VFS known to the kernel and capable 75 * of being mounted as root 76 * path := disk device name or other data used by the filesystem 77 * to locate its physical store 78 * 79 * If the environment variable vfs.root.mountfrom is a space separated list, 80 * each list element is tried in turn and the root filesystem will be mounted 81 * from the first one that succeeds. 82 * 83 * The environment variable vfs.root.mountfrom.options is a comma delimited 84 * set of string mount options. These mount options must be parseable 85 * by nmount() in the kernel. 86 */ 87 88 static int parse_mount(char **); 89 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 90 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS); 91 static void vfs_mountroot_wait(void); 92 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev); 93 94 /* 95 * The vnode of the system's root (/ in the filesystem, without chroot 96 * active.) 97 */ 98 struct vnode *rootvnode; 99 100 /* 101 * Mount of the system's /dev. 102 */ 103 struct mount *rootdevmp; 104 105 char *rootdevnames[2] = {NULL, NULL}; 106 107 struct mtx root_holds_mtx; 108 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 109 110 static TAILQ_HEAD(, root_hold_token) root_holds = 111 TAILQ_HEAD_INITIALIZER(root_holds); 112 113 enum action { 114 A_CONTINUE, 115 A_PANIC, 116 A_REBOOT, 117 A_RETRY 118 }; 119 120 enum rh_flags { 121 RH_FREE, 122 RH_ALLOC, 123 RH_ARG, 124 }; 125 126 static enum action root_mount_onfail = A_CONTINUE; 127 128 static int root_mount_mddev; 129 static int root_mount_complete; 130 131 /* By default wait up to 3 seconds for devices to appear. */ 132 static int root_mount_timeout = 3; 133 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 134 135 static int root_mount_always_wait = 0; 136 SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN, 137 &root_mount_always_wait, 0, 138 "Wait for root mount holds even if the root device already exists"); 139 140 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold, 141 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 142 NULL, 0, sysctl_vfs_root_mount_hold, "A", 143 "List of root mount hold tokens"); 144 145 static int 146 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS) 147 { 148 struct sbuf sb; 149 struct root_hold_token *h; 150 int error; 151 152 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 153 154 mtx_lock(&root_holds_mtx); 155 TAILQ_FOREACH(h, &root_holds, list) { 156 if (h != TAILQ_FIRST(&root_holds)) 157 sbuf_putc(&sb, ' '); 158 sbuf_printf(&sb, "%s", h->who); 159 } 160 mtx_unlock(&root_holds_mtx); 161 162 error = sbuf_finish(&sb); 163 if (error == 0) 164 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 165 sbuf_delete(&sb); 166 return (error); 167 } 168 169 struct root_hold_token * 170 root_mount_hold(const char *identifier) 171 { 172 struct root_hold_token *h; 173 174 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 175 h->flags = RH_ALLOC; 176 h->who = identifier; 177 mtx_lock(&root_holds_mtx); 178 TSHOLD("root mount"); 179 TAILQ_INSERT_TAIL(&root_holds, h, list); 180 mtx_unlock(&root_holds_mtx); 181 return (h); 182 } 183 184 void 185 root_mount_hold_token(const char *identifier, struct root_hold_token *h) 186 { 187 #ifdef INVARIANTS 188 struct root_hold_token *t; 189 #endif 190 191 h->flags = RH_ARG; 192 h->who = identifier; 193 mtx_lock(&root_holds_mtx); 194 #ifdef INVARIANTS 195 TAILQ_FOREACH(t, &root_holds, list) { 196 if (t == h) { 197 panic("Duplicate mount hold by '%s' on %p", 198 identifier, h); 199 } 200 } 201 #endif 202 TSHOLD("root mount"); 203 TAILQ_INSERT_TAIL(&root_holds, h, list); 204 mtx_unlock(&root_holds_mtx); 205 } 206 207 void 208 root_mount_rel(struct root_hold_token *h) 209 { 210 211 if (h == NULL || h->flags == RH_FREE) 212 return; 213 214 mtx_lock(&root_holds_mtx); 215 TAILQ_REMOVE(&root_holds, h, list); 216 TSRELEASE("root mount"); 217 wakeup(&root_holds); 218 mtx_unlock(&root_holds_mtx); 219 if (h->flags == RH_ALLOC) { 220 free(h, M_DEVBUF); 221 } else 222 h->flags = RH_FREE; 223 } 224 225 int 226 root_mounted(void) 227 { 228 229 /* No mutex is acquired here because int stores are atomic. */ 230 return (root_mount_complete); 231 } 232 233 static void 234 set_rootvnode(void) 235 { 236 237 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 238 panic("set_rootvnode: Cannot find root vnode"); 239 240 VOP_UNLOCK(rootvnode); 241 242 pwd_set_rootvnode(); 243 } 244 245 static int 246 vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 247 { 248 struct vfsoptlist *opts; 249 struct vfsconf *vfsp; 250 struct mount *mp; 251 int error; 252 253 *mpp = NULL; 254 255 if (rootdevmp != NULL) { 256 /* 257 * Already have /dev; this happens during rerooting. 258 */ 259 error = vfs_busy(rootdevmp, 0); 260 if (error != 0) 261 return (error); 262 *mpp = rootdevmp; 263 } else { 264 vfsp = vfs_byname("devfs"); 265 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 266 if (vfsp == NULL) 267 return (ENOENT); 268 269 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 270 271 error = VFS_MOUNT(mp); 272 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 273 if (error) 274 return (error); 275 276 error = VFS_STATFS(mp, &mp->mnt_stat); 277 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error)); 278 if (error) 279 return (error); 280 281 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 282 TAILQ_INIT(opts); 283 mp->mnt_opt = opts; 284 285 mtx_lock(&mountlist_mtx); 286 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 287 mtx_unlock(&mountlist_mtx); 288 289 *mpp = mp; 290 rootdevmp = mp; 291 vfs_op_exit(mp); 292 } 293 294 set_rootvnode(); 295 296 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 297 if (error) 298 printf("kern_symlink /dev -> / returns %d\n", error); 299 300 return (error); 301 } 302 303 static void 304 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 305 { 306 struct nameidata nd; 307 struct mount *mporoot, *mpnroot; 308 struct vnode *vp, *vporoot, *vpdevfs; 309 char *fspath; 310 int error; 311 312 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 313 314 /* Shuffle the mountlist. */ 315 mtx_lock(&mountlist_mtx); 316 mporoot = TAILQ_FIRST(&mountlist); 317 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 318 if (mporoot != mpdevfs) { 319 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 320 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 321 } 322 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 323 mtx_unlock(&mountlist_mtx); 324 325 cache_purgevfs(mporoot); 326 if (mporoot != mpdevfs) 327 cache_purgevfs(mpdevfs); 328 329 if (VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot)) 330 panic("vfs_mountroot_shuffle: Cannot find root vnode"); 331 332 VI_LOCK(vporoot); 333 vporoot->v_iflag &= ~VI_MOUNT; 334 vn_irflag_unset_locked(vporoot, VIRF_MOUNTPOINT); 335 vporoot->v_mountedhere = NULL; 336 VI_UNLOCK(vporoot); 337 mporoot->mnt_flag &= ~MNT_ROOTFS; 338 mporoot->mnt_vnodecovered = NULL; 339 vput(vporoot); 340 341 /* Set up the new rootvnode, and purge the cache */ 342 mpnroot->mnt_vnodecovered = NULL; 343 set_rootvnode(); 344 cache_purgevfs(rootvnode->v_mount); 345 346 if (mporoot != mpdevfs) { 347 /* Remount old root under /.mount or /mnt */ 348 fspath = "/.mount"; 349 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath); 350 error = namei(&nd); 351 if (error) { 352 fspath = "/mnt"; 353 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 354 fspath); 355 error = namei(&nd); 356 } 357 if (!error) { 358 NDFREE_PNBUF(&nd); 359 vp = nd.ni_vp; 360 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 361 if (!error) 362 error = vinvalbuf(vp, V_SAVE, 0, 0); 363 if (!error) { 364 cache_purge(vp); 365 VI_LOCK(vp); 366 mporoot->mnt_vnodecovered = vp; 367 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 368 vp->v_mountedhere = mporoot; 369 strlcpy(mporoot->mnt_stat.f_mntonname, 370 fspath, MNAMELEN); 371 VI_UNLOCK(vp); 372 VOP_UNLOCK(vp); 373 } else 374 vput(vp); 375 } 376 377 if (error) 378 printf("mountroot: unable to remount previous root " 379 "under /.mount or /mnt (error %d)\n", error); 380 } 381 382 /* Remount devfs under /dev */ 383 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev"); 384 error = namei(&nd); 385 if (!error) { 386 NDFREE_PNBUF(&nd); 387 vp = nd.ni_vp; 388 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 389 if (!error) 390 error = vinvalbuf(vp, V_SAVE, 0, 0); 391 if (!error) { 392 vpdevfs = mpdevfs->mnt_vnodecovered; 393 if (vpdevfs != NULL) { 394 cache_purge(vpdevfs); 395 VI_LOCK(vpdevfs); 396 vn_irflag_unset_locked(vpdevfs, VIRF_MOUNTPOINT); 397 vpdevfs->v_mountedhere = NULL; 398 VI_UNLOCK(vpdevfs); 399 vrele(vpdevfs); 400 } 401 VI_LOCK(vp); 402 mpdevfs->mnt_vnodecovered = vp; 403 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 404 vp->v_mountedhere = mpdevfs; 405 VI_UNLOCK(vp); 406 VOP_UNLOCK(vp); 407 } else 408 vput(vp); 409 } 410 if (error) 411 printf("mountroot: unable to remount devfs under /dev " 412 "(error %d)\n", error); 413 414 if (mporoot == mpdevfs) { 415 vfs_unbusy(mpdevfs); 416 /* Unlink the no longer needed /dev/dev -> / symlink */ 417 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 418 UIO_SYSSPACE, 0, 0); 419 if (error) 420 printf("mountroot: unable to unlink /dev/dev " 421 "(error %d)\n", error); 422 } 423 } 424 425 /* 426 * Configuration parser. 427 */ 428 429 /* Parser character classes. */ 430 #define CC_WHITESPACE -1 431 #define CC_NONWHITESPACE -2 432 433 /* Parse errors. */ 434 #define PE_EOF -1 435 #define PE_EOL -2 436 437 static __inline int 438 parse_peek(char **conf) 439 { 440 441 return (**conf); 442 } 443 444 static __inline void 445 parse_poke(char **conf, int c) 446 { 447 448 **conf = c; 449 } 450 451 static __inline void 452 parse_advance(char **conf) 453 { 454 455 (*conf)++; 456 } 457 458 static int 459 parse_skipto(char **conf, int mc) 460 { 461 int c, match; 462 463 while (1) { 464 c = parse_peek(conf); 465 if (c == 0) 466 return (PE_EOF); 467 switch (mc) { 468 case CC_WHITESPACE: 469 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 470 break; 471 case CC_NONWHITESPACE: 472 if (c == '\n') 473 return (PE_EOL); 474 match = (c != ' ' && c != '\t') ? 1 : 0; 475 break; 476 default: 477 match = (c == mc) ? 1 : 0; 478 break; 479 } 480 if (match) 481 break; 482 parse_advance(conf); 483 } 484 return (0); 485 } 486 487 static int 488 parse_token(char **conf, char **tok) 489 { 490 char *p; 491 size_t len; 492 int error; 493 494 *tok = NULL; 495 error = parse_skipto(conf, CC_NONWHITESPACE); 496 if (error) 497 return (error); 498 p = *conf; 499 error = parse_skipto(conf, CC_WHITESPACE); 500 len = *conf - p; 501 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 502 bcopy(p, *tok, len); 503 return (0); 504 } 505 506 static void 507 parse_dir_ask_printenv(const char *var) 508 { 509 char *val; 510 511 val = kern_getenv(var); 512 if (val != NULL) { 513 printf(" %s=%s\n", var, val); 514 freeenv(val); 515 } 516 } 517 518 static int 519 parse_dir_ask(char **conf) 520 { 521 char name[80]; 522 char *mnt; 523 int error; 524 525 vfs_mountroot_wait(); 526 527 printf("\nLoader variables:\n"); 528 parse_dir_ask_printenv("vfs.root.mountfrom"); 529 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 530 531 printf("\nManual root filesystem specification:\n"); 532 printf(" <fstype>:<device> [options]\n"); 533 printf(" Mount <device> using filesystem <fstype>\n"); 534 printf(" and with the specified (optional) option list.\n"); 535 printf("\n"); 536 printf(" eg. ufs:/dev/da0s1a\n"); 537 printf(" zfs:zroot/ROOT/default\n"); 538 printf(" cd9660:/dev/cd0 ro\n"); 539 printf(" (which is equivalent to: "); 540 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 541 printf("\n"); 542 printf(" ? List valid disk boot devices\n"); 543 printf(" . Yield 1 second (for background tasks)\n"); 544 printf(" <empty line> Abort manual input\n"); 545 546 do { 547 error = EINVAL; 548 printf("\nmountroot> "); 549 cngets(name, sizeof(name), GETS_ECHO); 550 if (name[0] == '\0') 551 break; 552 if (name[0] == '?' && name[1] == '\0') { 553 printf("\nList of GEOM managed disk devices:\n "); 554 g_dev_print(); 555 continue; 556 } 557 if (name[0] == '.' && name[1] == '\0') { 558 pause("rmask", hz); 559 continue; 560 } 561 mnt = name; 562 error = parse_mount(&mnt); 563 if (error == -1) 564 printf("Invalid file system specification.\n"); 565 } while (error != 0); 566 567 return (error); 568 } 569 570 static int 571 parse_dir_md(char **conf) 572 { 573 struct stat sb; 574 struct thread *td; 575 struct md_ioctl *mdio; 576 char *path, *tok; 577 int error, fd, len; 578 579 td = curthread; 580 fd = -1; 581 582 error = parse_token(conf, &tok); 583 if (error) 584 return (error); 585 586 len = strlen(tok); 587 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 588 path = (void *)(mdio + 1); 589 bcopy(tok, path, len); 590 free(tok, M_TEMP); 591 592 /* Get file status. */ 593 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb); 594 if (error) 595 goto out; 596 597 /* Open /dev/mdctl so that we can attach/detach. */ 598 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 599 O_RDWR, 0); 600 if (error) 601 goto out; 602 603 fd = td->td_retval[0]; 604 mdio->md_version = MDIOVERSION; 605 mdio->md_type = MD_VNODE; 606 607 if (root_mount_mddev != -1) { 608 mdio->md_unit = root_mount_mddev; 609 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 610 /* Ignore errors. We don't care. */ 611 root_mount_mddev = -1; 612 } 613 614 mdio->md_file = (void *)(mdio + 1); 615 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 616 mdio->md_mediasize = sb.st_size; 617 mdio->md_unit = 0; 618 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 619 if (error) 620 goto out; 621 622 if (mdio->md_unit > 9) { 623 printf("rootmount: too many md units\n"); 624 mdio->md_file = NULL; 625 mdio->md_options = 0; 626 mdio->md_mediasize = 0; 627 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 628 /* Ignore errors. We don't care. */ 629 error = ERANGE; 630 goto out; 631 } 632 633 root_mount_mddev = mdio->md_unit; 634 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 635 636 out: 637 if (fd >= 0) 638 (void)kern_close(td, fd); 639 free(mdio, M_TEMP); 640 return (error); 641 } 642 643 static int 644 parse_dir_onfail(char **conf) 645 { 646 char *action; 647 int error; 648 649 error = parse_token(conf, &action); 650 if (error) 651 return (error); 652 653 if (!strcmp(action, "continue")) 654 root_mount_onfail = A_CONTINUE; 655 else if (!strcmp(action, "panic")) 656 root_mount_onfail = A_PANIC; 657 else if (!strcmp(action, "reboot")) 658 root_mount_onfail = A_REBOOT; 659 else if (!strcmp(action, "retry")) 660 root_mount_onfail = A_RETRY; 661 else { 662 printf("rootmount: %s: unknown action\n", action); 663 error = EINVAL; 664 } 665 666 free(action, M_TEMP); 667 return (0); 668 } 669 670 static int 671 parse_dir_timeout(char **conf) 672 { 673 char *tok, *endtok; 674 long secs; 675 int error; 676 677 error = parse_token(conf, &tok); 678 if (error) 679 return (error); 680 681 secs = strtol(tok, &endtok, 0); 682 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 683 if (!error) 684 root_mount_timeout = secs; 685 free(tok, M_TEMP); 686 return (error); 687 } 688 689 static int 690 parse_directive(char **conf) 691 { 692 char *dir; 693 int error; 694 695 error = parse_token(conf, &dir); 696 if (error) 697 return (error); 698 699 if (strcmp(dir, ".ask") == 0) 700 error = parse_dir_ask(conf); 701 else if (strcmp(dir, ".md") == 0) 702 error = parse_dir_md(conf); 703 else if (strcmp(dir, ".onfail") == 0) 704 error = parse_dir_onfail(conf); 705 else if (strcmp(dir, ".timeout") == 0) 706 error = parse_dir_timeout(conf); 707 else { 708 printf("mountroot: invalid directive `%s'\n", dir); 709 /* Ignore the rest of the line. */ 710 (void)parse_skipto(conf, '\n'); 711 error = EINVAL; 712 } 713 free(dir, M_TEMP); 714 return (error); 715 } 716 717 static bool 718 parse_mount_dev_present(const char *dev) 719 { 720 struct nameidata nd; 721 int error; 722 723 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, dev); 724 error = namei(&nd); 725 if (error != 0) 726 return (false); 727 vrele(nd.ni_vp); 728 NDFREE_PNBUF(&nd); 729 return (true); 730 } 731 732 #define ERRMSGL 255 733 static int 734 parse_mount(char **conf) 735 { 736 char *errmsg; 737 struct mntarg *ma; 738 char *dev, *fs, *opts, *tok; 739 int delay, error, timeout; 740 741 error = parse_token(conf, &tok); 742 if (error) 743 return (error); 744 fs = tok; 745 error = parse_skipto(&tok, ':'); 746 if (error) { 747 free(fs, M_TEMP); 748 return (error); 749 } 750 parse_poke(&tok, '\0'); 751 parse_advance(&tok); 752 dev = tok; 753 754 if (root_mount_mddev != -1) { 755 /* Handle substitution for the md unit number. */ 756 tok = strstr(dev, "md#"); 757 if (tok != NULL) 758 tok[2] = '0' + root_mount_mddev; 759 } 760 761 /* Parse options. */ 762 error = parse_token(conf, &tok); 763 opts = (error == 0) ? tok : NULL; 764 765 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 766 (opts != NULL) ? opts : ""); 767 768 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 769 770 if (vfs_byname(fs) == NULL) { 771 strlcpy(errmsg, "unknown file system", ERRMSGL); 772 error = ENOENT; 773 goto out; 774 } 775 776 error = vfs_mountroot_wait_if_neccessary(fs, dev); 777 if (error != 0) 778 goto out; 779 780 delay = hz / 10; 781 timeout = root_mount_timeout * hz; 782 783 for (;;) { 784 ma = NULL; 785 ma = mount_arg(ma, "fstype", fs, -1); 786 ma = mount_arg(ma, "fspath", "/", -1); 787 ma = mount_arg(ma, "from", dev, -1); 788 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 789 ma = mount_arg(ma, "ro", NULL, 0); 790 ma = parse_mountroot_options(ma, opts); 791 792 error = kernel_mount(ma, MNT_ROOTFS); 793 if (error == 0 || error == EILSEQ || timeout <= 0) 794 break; 795 796 if (root_mount_timeout * hz == timeout || 797 (bootverbose && timeout % hz == 0)) { 798 printf("Mounting from %s:%s failed with error %d; " 799 "retrying for %d more second%s\n", fs, dev, error, 800 timeout / hz, (timeout / hz > 1) ? "s" : ""); 801 } 802 pause("rmretry", delay); 803 timeout -= delay; 804 } 805 out: 806 if (error) { 807 printf("Mounting from %s:%s failed with error %d", 808 fs, dev, error); 809 if (errmsg[0] != '\0') 810 printf(": %s", errmsg); 811 printf(".\n"); 812 } 813 free(fs, M_TEMP); 814 free(errmsg, M_TEMP); 815 if (opts != NULL) 816 free(opts, M_TEMP); 817 /* kernel_mount can return -1 on error. */ 818 return ((error < 0) ? EDOOFUS : error); 819 } 820 #undef ERRMSGL 821 822 static int 823 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 824 { 825 struct mount *mp; 826 char *conf; 827 int error; 828 829 root_mount_mddev = -1; 830 831 retry: 832 conf = sbuf_data(sb); 833 mp = TAILQ_NEXT(mpdevfs, mnt_list); 834 error = (mp == NULL) ? 0 : EDOOFUS; 835 root_mount_onfail = A_CONTINUE; 836 while (mp == NULL) { 837 error = parse_skipto(&conf, CC_NONWHITESPACE); 838 if (error == PE_EOL) { 839 parse_advance(&conf); 840 continue; 841 } 842 if (error < 0) 843 break; 844 switch (parse_peek(&conf)) { 845 case '#': 846 error = parse_skipto(&conf, '\n'); 847 break; 848 case '.': 849 error = parse_directive(&conf); 850 break; 851 default: 852 error = parse_mount(&conf); 853 if (error == -1) { 854 printf("mountroot: invalid file system " 855 "specification.\n"); 856 error = 0; 857 } 858 break; 859 } 860 if (error < 0) 861 break; 862 /* Ignore any trailing garbage on the line. */ 863 if (parse_peek(&conf) != '\n') { 864 printf("mountroot: advancing to next directive...\n"); 865 (void)parse_skipto(&conf, '\n'); 866 } 867 mp = TAILQ_NEXT(mpdevfs, mnt_list); 868 } 869 if (mp != NULL) 870 return (0); 871 872 /* 873 * We failed to mount (a new) root. 874 */ 875 switch (root_mount_onfail) { 876 case A_CONTINUE: 877 break; 878 case A_PANIC: 879 panic("mountroot: unable to (re-)mount root."); 880 /* NOTREACHED */ 881 case A_RETRY: 882 goto retry; 883 case A_REBOOT: 884 kern_reboot(RB_NOSYNC); 885 /* NOTREACHED */ 886 } 887 888 return (error); 889 } 890 891 static void 892 vfs_mountroot_conf0(struct sbuf *sb) 893 { 894 char *s, *tok, *mnt, *opt; 895 int error; 896 897 sbuf_cat(sb, ".onfail panic\n"); 898 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 899 if (boothowto & RB_ASKNAME) 900 sbuf_cat(sb, ".ask\n"); 901 #ifdef ROOTDEVNAME 902 if (boothowto & RB_DFLTROOT) 903 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 904 #endif 905 if (boothowto & RB_CDROM) { 906 sbuf_cat(sb, "cd9660:/dev/cd0 ro\n"); 907 sbuf_cat(sb, ".timeout 0\n"); 908 sbuf_cat(sb, "cd9660:/dev/cd1 ro\n"); 909 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 910 } 911 s = kern_getenv("vfs.root.mountfrom"); 912 if (s != NULL) { 913 opt = kern_getenv("vfs.root.mountfrom.options"); 914 tok = s; 915 error = parse_token(&tok, &mnt); 916 while (!error) { 917 sbuf_printf(sb, "%s %s\n", mnt, 918 (opt != NULL) ? opt : ""); 919 free(mnt, M_TEMP); 920 error = parse_token(&tok, &mnt); 921 } 922 if (opt != NULL) 923 freeenv(opt); 924 freeenv(s); 925 } 926 if (rootdevnames[0] != NULL) 927 sbuf_printf(sb, "%s\n", rootdevnames[0]); 928 if (rootdevnames[1] != NULL) 929 sbuf_printf(sb, "%s\n", rootdevnames[1]); 930 #ifdef ROOTDEVNAME 931 if (!(boothowto & RB_DFLTROOT)) 932 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 933 #endif 934 if (!(boothowto & RB_ASKNAME)) 935 sbuf_cat(sb, ".ask\n"); 936 } 937 938 static int 939 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 940 { 941 static char buf[128]; 942 struct nameidata nd; 943 off_t ofs; 944 ssize_t resid; 945 int error, flags, len; 946 947 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf"); 948 flags = FREAD; 949 error = vn_open(&nd, &flags, 0, NULL); 950 if (error) 951 return (error); 952 953 NDFREE_PNBUF(&nd); 954 ofs = 0; 955 len = sizeof(buf) - 1; 956 while (1) { 957 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 958 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 959 NOCRED, &resid, td); 960 if (error) 961 break; 962 if (resid == len) 963 break; 964 buf[len - resid] = 0; 965 sbuf_printf(sb, "%s", buf); 966 ofs += len - resid; 967 } 968 969 VOP_UNLOCK(nd.ni_vp); 970 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 971 return (error); 972 } 973 974 static void 975 vfs_mountroot_wait(void) 976 { 977 struct root_hold_token *h; 978 struct thread *td; 979 struct timeval lastfail; 980 int curfail; 981 982 TSENTER(); 983 984 curfail = 0; 985 lastfail.tv_sec = 0; 986 eventratecheck(&lastfail, &curfail, 1); 987 td = curthread; 988 while (1) { 989 g_waitidle(td); 990 mtx_lock(&root_holds_mtx); 991 if (TAILQ_EMPTY(&root_holds)) { 992 mtx_unlock(&root_holds_mtx); 993 break; 994 } 995 if (eventratecheck(&lastfail, &curfail, 1)) { 996 printf("Root mount waiting for:"); 997 TAILQ_FOREACH(h, &root_holds, list) 998 printf(" %s", h->who); 999 printf("\n"); 1000 } 1001 TSWAIT("root mount"); 1002 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 1003 hz); 1004 TSUNWAIT("root mount"); 1005 } 1006 g_waitidle(td); 1007 1008 TSEXIT(); 1009 } 1010 1011 static int 1012 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 1013 { 1014 int delay, timeout; 1015 1016 /* 1017 * In case of ZFS and NFS we don't have a way to wait for 1018 * specific device. Also do the wait if the user forced that 1019 * behaviour by setting vfs.root_mount_always_wait=1. 1020 */ 1021 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 1022 strcmp(fs, "p9fs") == 0 || 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