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, fspath); 354 error = namei(&nd); 355 if (error) { 356 NDFREE(&nd, NDF_ONLY_PNBUF); 357 fspath = "/mnt"; 358 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 359 fspath); 360 error = namei(&nd); 361 } 362 if (!error) { 363 vp = nd.ni_vp; 364 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 365 if (!error) 366 error = vinvalbuf(vp, V_SAVE, 0, 0); 367 if (!error) { 368 cache_purge(vp); 369 VI_LOCK(vp); 370 mporoot->mnt_vnodecovered = vp; 371 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 372 vp->v_mountedhere = mporoot; 373 strlcpy(mporoot->mnt_stat.f_mntonname, 374 fspath, MNAMELEN); 375 VI_UNLOCK(vp); 376 VOP_UNLOCK(vp); 377 } else 378 vput(vp); 379 } 380 NDFREE(&nd, NDF_ONLY_PNBUF); 381 382 if (error) 383 printf("mountroot: unable to remount previous root " 384 "under /.mount or /mnt (error %d)\n", error); 385 } 386 387 /* Remount devfs under /dev */ 388 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev"); 389 error = namei(&nd); 390 if (!error) { 391 vp = nd.ni_vp; 392 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 393 if (!error) 394 error = vinvalbuf(vp, V_SAVE, 0, 0); 395 if (!error) { 396 vpdevfs = mpdevfs->mnt_vnodecovered; 397 if (vpdevfs != NULL) { 398 cache_purge(vpdevfs); 399 VI_LOCK(vpdevfs); 400 vn_irflag_unset_locked(vpdevfs, VIRF_MOUNTPOINT); 401 vpdevfs->v_mountedhere = NULL; 402 VI_UNLOCK(vpdevfs); 403 vrele(vpdevfs); 404 } 405 VI_LOCK(vp); 406 mpdevfs->mnt_vnodecovered = vp; 407 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 408 vp->v_mountedhere = mpdevfs; 409 VI_UNLOCK(vp); 410 VOP_UNLOCK(vp); 411 } else 412 vput(vp); 413 } 414 if (error) 415 printf("mountroot: unable to remount devfs under /dev " 416 "(error %d)\n", error); 417 NDFREE(&nd, NDF_ONLY_PNBUF); 418 419 if (mporoot == mpdevfs) { 420 vfs_unbusy(mpdevfs); 421 /* Unlink the no longer needed /dev/dev -> / symlink */ 422 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 423 UIO_SYSSPACE, 0, 0); 424 if (error) 425 printf("mountroot: unable to unlink /dev/dev " 426 "(error %d)\n", error); 427 } 428 } 429 430 /* 431 * Configuration parser. 432 */ 433 434 /* Parser character classes. */ 435 #define CC_WHITESPACE -1 436 #define CC_NONWHITESPACE -2 437 438 /* Parse errors. */ 439 #define PE_EOF -1 440 #define PE_EOL -2 441 442 static __inline int 443 parse_peek(char **conf) 444 { 445 446 return (**conf); 447 } 448 449 static __inline void 450 parse_poke(char **conf, int c) 451 { 452 453 **conf = c; 454 } 455 456 static __inline void 457 parse_advance(char **conf) 458 { 459 460 (*conf)++; 461 } 462 463 static int 464 parse_skipto(char **conf, int mc) 465 { 466 int c, match; 467 468 while (1) { 469 c = parse_peek(conf); 470 if (c == 0) 471 return (PE_EOF); 472 switch (mc) { 473 case CC_WHITESPACE: 474 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 475 break; 476 case CC_NONWHITESPACE: 477 if (c == '\n') 478 return (PE_EOL); 479 match = (c != ' ' && c != '\t') ? 1 : 0; 480 break; 481 default: 482 match = (c == mc) ? 1 : 0; 483 break; 484 } 485 if (match) 486 break; 487 parse_advance(conf); 488 } 489 return (0); 490 } 491 492 static int 493 parse_token(char **conf, char **tok) 494 { 495 char *p; 496 size_t len; 497 int error; 498 499 *tok = NULL; 500 error = parse_skipto(conf, CC_NONWHITESPACE); 501 if (error) 502 return (error); 503 p = *conf; 504 error = parse_skipto(conf, CC_WHITESPACE); 505 len = *conf - p; 506 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 507 bcopy(p, *tok, len); 508 return (0); 509 } 510 511 static void 512 parse_dir_ask_printenv(const char *var) 513 { 514 char *val; 515 516 val = kern_getenv(var); 517 if (val != NULL) { 518 printf(" %s=%s\n", var, val); 519 freeenv(val); 520 } 521 } 522 523 static int 524 parse_dir_ask(char **conf) 525 { 526 char name[80]; 527 char *mnt; 528 int error; 529 530 vfs_mountroot_wait(); 531 532 printf("\nLoader variables:\n"); 533 parse_dir_ask_printenv("vfs.root.mountfrom"); 534 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 535 536 printf("\nManual root filesystem specification:\n"); 537 printf(" <fstype>:<device> [options]\n"); 538 printf(" Mount <device> using filesystem <fstype>\n"); 539 printf(" and with the specified (optional) option list.\n"); 540 printf("\n"); 541 printf(" eg. ufs:/dev/da0s1a\n"); 542 printf(" zfs:zroot/ROOT/default\n"); 543 printf(" cd9660:/dev/cd0 ro\n"); 544 printf(" (which is equivalent to: "); 545 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 546 printf("\n"); 547 printf(" ? List valid disk boot devices\n"); 548 printf(" . Yield 1 second (for background tasks)\n"); 549 printf(" <empty line> Abort manual input\n"); 550 551 do { 552 error = EINVAL; 553 printf("\nmountroot> "); 554 cngets(name, sizeof(name), GETS_ECHO); 555 if (name[0] == '\0') 556 break; 557 if (name[0] == '?' && name[1] == '\0') { 558 printf("\nList of GEOM managed disk devices:\n "); 559 g_dev_print(); 560 continue; 561 } 562 if (name[0] == '.' && name[1] == '\0') { 563 pause("rmask", hz); 564 continue; 565 } 566 mnt = name; 567 error = parse_mount(&mnt); 568 if (error == -1) 569 printf("Invalid file system specification.\n"); 570 } while (error != 0); 571 572 return (error); 573 } 574 575 static int 576 parse_dir_md(char **conf) 577 { 578 struct stat sb; 579 struct thread *td; 580 struct md_ioctl *mdio; 581 char *path, *tok; 582 int error, fd, len; 583 584 td = curthread; 585 fd = -1; 586 587 error = parse_token(conf, &tok); 588 if (error) 589 return (error); 590 591 len = strlen(tok); 592 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 593 path = (void *)(mdio + 1); 594 bcopy(tok, path, len); 595 free(tok, M_TEMP); 596 597 /* Get file status. */ 598 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 599 if (error) 600 goto out; 601 602 /* Open /dev/mdctl so that we can attach/detach. */ 603 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 604 O_RDWR, 0); 605 if (error) 606 goto out; 607 608 fd = td->td_retval[0]; 609 mdio->md_version = MDIOVERSION; 610 mdio->md_type = MD_VNODE; 611 612 if (root_mount_mddev != -1) { 613 mdio->md_unit = root_mount_mddev; 614 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 615 /* Ignore errors. We don't care. */ 616 root_mount_mddev = -1; 617 } 618 619 mdio->md_file = (void *)(mdio + 1); 620 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 621 mdio->md_mediasize = sb.st_size; 622 mdio->md_unit = 0; 623 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 624 if (error) 625 goto out; 626 627 if (mdio->md_unit > 9) { 628 printf("rootmount: too many md units\n"); 629 mdio->md_file = NULL; 630 mdio->md_options = 0; 631 mdio->md_mediasize = 0; 632 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 633 /* Ignore errors. We don't care. */ 634 error = ERANGE; 635 goto out; 636 } 637 638 root_mount_mddev = mdio->md_unit; 639 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 640 641 out: 642 if (fd >= 0) 643 (void)kern_close(td, fd); 644 free(mdio, M_TEMP); 645 return (error); 646 } 647 648 static int 649 parse_dir_onfail(char **conf) 650 { 651 char *action; 652 int error; 653 654 error = parse_token(conf, &action); 655 if (error) 656 return (error); 657 658 if (!strcmp(action, "continue")) 659 root_mount_onfail = A_CONTINUE; 660 else if (!strcmp(action, "panic")) 661 root_mount_onfail = A_PANIC; 662 else if (!strcmp(action, "reboot")) 663 root_mount_onfail = A_REBOOT; 664 else if (!strcmp(action, "retry")) 665 root_mount_onfail = A_RETRY; 666 else { 667 printf("rootmount: %s: unknown action\n", action); 668 error = EINVAL; 669 } 670 671 free(action, M_TEMP); 672 return (0); 673 } 674 675 static int 676 parse_dir_timeout(char **conf) 677 { 678 char *tok, *endtok; 679 long secs; 680 int error; 681 682 error = parse_token(conf, &tok); 683 if (error) 684 return (error); 685 686 secs = strtol(tok, &endtok, 0); 687 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 688 if (!error) 689 root_mount_timeout = secs; 690 free(tok, M_TEMP); 691 return (error); 692 } 693 694 static int 695 parse_directive(char **conf) 696 { 697 char *dir; 698 int error; 699 700 error = parse_token(conf, &dir); 701 if (error) 702 return (error); 703 704 if (strcmp(dir, ".ask") == 0) 705 error = parse_dir_ask(conf); 706 else if (strcmp(dir, ".md") == 0) 707 error = parse_dir_md(conf); 708 else if (strcmp(dir, ".onfail") == 0) 709 error = parse_dir_onfail(conf); 710 else if (strcmp(dir, ".timeout") == 0) 711 error = parse_dir_timeout(conf); 712 else { 713 printf("mountroot: invalid directive `%s'\n", dir); 714 /* Ignore the rest of the line. */ 715 (void)parse_skipto(conf, '\n'); 716 error = EINVAL; 717 } 718 free(dir, M_TEMP); 719 return (error); 720 } 721 722 static int 723 parse_mount_dev_present(const char *dev) 724 { 725 struct nameidata nd; 726 int error; 727 728 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev); 729 error = namei(&nd); 730 if (!error) 731 vput(nd.ni_vp); 732 NDFREE(&nd, NDF_ONLY_PNBUF); 733 return (error != 0) ? 0 : 1; 734 } 735 736 #define ERRMSGL 255 737 static int 738 parse_mount(char **conf) 739 { 740 char *errmsg; 741 struct mntarg *ma; 742 char *dev, *fs, *opts, *tok; 743 int delay, error, timeout; 744 745 error = parse_token(conf, &tok); 746 if (error) 747 return (error); 748 fs = tok; 749 error = parse_skipto(&tok, ':'); 750 if (error) { 751 free(fs, M_TEMP); 752 return (error); 753 } 754 parse_poke(&tok, '\0'); 755 parse_advance(&tok); 756 dev = tok; 757 758 if (root_mount_mddev != -1) { 759 /* Handle substitution for the md unit number. */ 760 tok = strstr(dev, "md#"); 761 if (tok != NULL) 762 tok[2] = '0' + root_mount_mddev; 763 } 764 765 /* Parse options. */ 766 error = parse_token(conf, &tok); 767 opts = (error == 0) ? tok : NULL; 768 769 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 770 (opts != NULL) ? opts : ""); 771 772 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 773 774 if (vfs_byname(fs) == NULL) { 775 strlcpy(errmsg, "unknown file system", ERRMSGL); 776 error = ENOENT; 777 goto out; 778 } 779 780 error = vfs_mountroot_wait_if_neccessary(fs, dev); 781 if (error != 0) 782 goto out; 783 784 delay = hz / 10; 785 timeout = root_mount_timeout * hz; 786 787 for (;;) { 788 ma = NULL; 789 ma = mount_arg(ma, "fstype", fs, -1); 790 ma = mount_arg(ma, "fspath", "/", -1); 791 ma = mount_arg(ma, "from", dev, -1); 792 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 793 ma = mount_arg(ma, "ro", NULL, 0); 794 ma = parse_mountroot_options(ma, opts); 795 796 error = kernel_mount(ma, MNT_ROOTFS); 797 if (error == 0 || timeout <= 0) 798 break; 799 800 if (root_mount_timeout * hz == timeout || 801 (bootverbose && timeout % hz == 0)) { 802 printf("Mounting from %s:%s failed with error %d; " 803 "retrying for %d more second%s\n", fs, dev, error, 804 timeout / hz, (timeout / hz > 1) ? "s" : ""); 805 } 806 pause("rmretry", delay); 807 timeout -= delay; 808 } 809 out: 810 if (error) { 811 printf("Mounting from %s:%s failed with error %d", 812 fs, dev, error); 813 if (errmsg[0] != '\0') 814 printf(": %s", errmsg); 815 printf(".\n"); 816 } 817 free(fs, M_TEMP); 818 free(errmsg, M_TEMP); 819 if (opts != NULL) 820 free(opts, M_TEMP); 821 /* kernel_mount can return -1 on error. */ 822 return ((error < 0) ? EDOOFUS : error); 823 } 824 #undef ERRMSGL 825 826 static int 827 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 828 { 829 struct mount *mp; 830 char *conf; 831 int error; 832 833 root_mount_mddev = -1; 834 835 retry: 836 conf = sbuf_data(sb); 837 mp = TAILQ_NEXT(mpdevfs, mnt_list); 838 error = (mp == NULL) ? 0 : EDOOFUS; 839 root_mount_onfail = A_CONTINUE; 840 while (mp == NULL) { 841 error = parse_skipto(&conf, CC_NONWHITESPACE); 842 if (error == PE_EOL) { 843 parse_advance(&conf); 844 continue; 845 } 846 if (error < 0) 847 break; 848 switch (parse_peek(&conf)) { 849 case '#': 850 error = parse_skipto(&conf, '\n'); 851 break; 852 case '.': 853 error = parse_directive(&conf); 854 break; 855 default: 856 error = parse_mount(&conf); 857 if (error == -1) { 858 printf("mountroot: invalid file system " 859 "specification.\n"); 860 error = 0; 861 } 862 break; 863 } 864 if (error < 0) 865 break; 866 /* Ignore any trailing garbage on the line. */ 867 if (parse_peek(&conf) != '\n') { 868 printf("mountroot: advancing to next directive...\n"); 869 (void)parse_skipto(&conf, '\n'); 870 } 871 mp = TAILQ_NEXT(mpdevfs, mnt_list); 872 } 873 if (mp != NULL) 874 return (0); 875 876 /* 877 * We failed to mount (a new) root. 878 */ 879 switch (root_mount_onfail) { 880 case A_CONTINUE: 881 break; 882 case A_PANIC: 883 panic("mountroot: unable to (re-)mount root."); 884 /* NOTREACHED */ 885 case A_RETRY: 886 goto retry; 887 case A_REBOOT: 888 kern_reboot(RB_NOSYNC); 889 /* NOTREACHED */ 890 } 891 892 return (error); 893 } 894 895 static void 896 vfs_mountroot_conf0(struct sbuf *sb) 897 { 898 char *s, *tok, *mnt, *opt; 899 int error; 900 901 sbuf_printf(sb, ".onfail panic\n"); 902 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 903 if (boothowto & RB_ASKNAME) 904 sbuf_printf(sb, ".ask\n"); 905 #ifdef ROOTDEVNAME 906 if (boothowto & RB_DFLTROOT) 907 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 908 #endif 909 if (boothowto & RB_CDROM) { 910 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 911 sbuf_printf(sb, ".timeout 0\n"); 912 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 913 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 914 } 915 s = kern_getenv("vfs.root.mountfrom"); 916 if (s != NULL) { 917 opt = kern_getenv("vfs.root.mountfrom.options"); 918 tok = s; 919 error = parse_token(&tok, &mnt); 920 while (!error) { 921 sbuf_printf(sb, "%s %s\n", mnt, 922 (opt != NULL) ? opt : ""); 923 free(mnt, M_TEMP); 924 error = parse_token(&tok, &mnt); 925 } 926 if (opt != NULL) 927 freeenv(opt); 928 freeenv(s); 929 } 930 if (rootdevnames[0] != NULL) 931 sbuf_printf(sb, "%s\n", rootdevnames[0]); 932 if (rootdevnames[1] != NULL) 933 sbuf_printf(sb, "%s\n", rootdevnames[1]); 934 #ifdef ROOTDEVNAME 935 if (!(boothowto & RB_DFLTROOT)) 936 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 937 #endif 938 if (!(boothowto & RB_ASKNAME)) 939 sbuf_printf(sb, ".ask\n"); 940 } 941 942 static int 943 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 944 { 945 static char buf[128]; 946 struct nameidata nd; 947 off_t ofs; 948 ssize_t resid; 949 int error, flags, len; 950 951 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf"); 952 flags = FREAD; 953 error = vn_open(&nd, &flags, 0, NULL); 954 if (error) 955 return (error); 956 957 NDFREE(&nd, NDF_ONLY_PNBUF); 958 ofs = 0; 959 len = sizeof(buf) - 1; 960 while (1) { 961 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 962 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 963 NOCRED, &resid, td); 964 if (error) 965 break; 966 if (resid == len) 967 break; 968 buf[len - resid] = 0; 969 sbuf_printf(sb, "%s", buf); 970 ofs += len - resid; 971 } 972 973 VOP_UNLOCK(nd.ni_vp); 974 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 975 return (error); 976 } 977 978 static void 979 vfs_mountroot_wait(void) 980 { 981 struct root_hold_token *h; 982 struct timeval lastfail; 983 int curfail; 984 985 TSENTER(); 986 987 curfail = 0; 988 lastfail.tv_sec = 0; 989 ppsratecheck(&lastfail, &curfail, 1); 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 g_waitidle(); 1009 1010 TSEXIT(); 1011 } 1012 1013 static int 1014 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 1015 { 1016 int delay, timeout; 1017 1018 /* 1019 * In case of ZFS and NFS we don't have a way to wait for 1020 * specific device. Also do the wait if the user forced that 1021 * behaviour by setting vfs.root_mount_always_wait=1. 1022 */ 1023 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 1024 dev[0] == '\0' || root_mount_always_wait != 0) { 1025 vfs_mountroot_wait(); 1026 return (0); 1027 } 1028 1029 /* 1030 * Otherwise, no point in waiting if the device is already there. 1031 * Note that we must wait for GEOM to finish reconfiguring itself, 1032 * eg for geom_part(4) to finish tasting. 1033 */ 1034 g_waitidle(); 1035 if (parse_mount_dev_present(dev)) 1036 return (0); 1037 1038 /* 1039 * No luck. Let's wait. This code looks weird, but it's that way 1040 * to behave exactly as it used to work before. 1041 */ 1042 vfs_mountroot_wait(); 1043 if (parse_mount_dev_present(dev)) 1044 return (0); 1045 printf("mountroot: waiting for device %s...\n", dev); 1046 delay = hz / 10; 1047 timeout = root_mount_timeout * hz; 1048 do { 1049 pause("rmdev", delay); 1050 timeout -= delay; 1051 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1052 1053 if (timeout <= 0) 1054 return (ENODEV); 1055 1056 return (0); 1057 } 1058 1059 void 1060 vfs_mountroot(void) 1061 { 1062 struct mount *mp; 1063 struct sbuf *sb; 1064 struct thread *td; 1065 time_t timebase; 1066 int error; 1067 1068 mtx_assert(&Giant, MA_NOTOWNED); 1069 1070 TSENTER(); 1071 1072 td = curthread; 1073 1074 sb = sbuf_new_auto(); 1075 vfs_mountroot_conf0(sb); 1076 sbuf_finish(sb); 1077 1078 error = vfs_mountroot_devfs(td, &mp); 1079 while (!error) { 1080 error = vfs_mountroot_parse(sb, mp); 1081 if (!error) { 1082 vfs_mountroot_shuffle(td, mp); 1083 sbuf_clear(sb); 1084 error = vfs_mountroot_readconf(td, sb); 1085 sbuf_finish(sb); 1086 } 1087 } 1088 1089 sbuf_delete(sb); 1090 1091 /* 1092 * Iterate over all currently mounted file systems and use 1093 * the time stamp found to check and/or initialize the RTC. 1094 * Call inittodr() only once and pass it the largest of the 1095 * timestamps we encounter. 1096 */ 1097 timebase = 0; 1098 mtx_lock(&mountlist_mtx); 1099 mp = TAILQ_FIRST(&mountlist); 1100 while (mp != NULL) { 1101 if (mp->mnt_time > timebase) 1102 timebase = mp->mnt_time; 1103 mp = TAILQ_NEXT(mp, mnt_list); 1104 } 1105 mtx_unlock(&mountlist_mtx); 1106 inittodr(timebase); 1107 1108 /* Keep prison0's root in sync with the global rootvnode. */ 1109 mtx_lock(&prison0.pr_mtx); 1110 prison0.pr_root = rootvnode; 1111 vref(prison0.pr_root); 1112 mtx_unlock(&prison0.pr_mtx); 1113 1114 mtx_lock(&root_holds_mtx); 1115 atomic_store_rel_int(&root_mount_complete, 1); 1116 wakeup(&root_mount_complete); 1117 mtx_unlock(&root_holds_mtx); 1118 1119 EVENTHANDLER_INVOKE(mountroot); 1120 1121 TSEXIT(); 1122 } 1123 1124 static struct mntarg * 1125 parse_mountroot_options(struct mntarg *ma, const char *options) 1126 { 1127 char *p; 1128 char *name, *name_arg; 1129 char *val, *val_arg; 1130 char *opts; 1131 1132 if (options == NULL || options[0] == '\0') 1133 return (ma); 1134 1135 p = opts = strdup(options, M_MOUNT); 1136 if (opts == NULL) { 1137 return (ma); 1138 } 1139 1140 while((name = strsep(&p, ",")) != NULL) { 1141 if (name[0] == '\0') 1142 break; 1143 1144 val = strchr(name, '='); 1145 if (val != NULL) { 1146 *val = '\0'; 1147 ++val; 1148 } 1149 if (strcmp(name, "rw") == 0 || strcmp(name, "noro") == 0) { 1150 /* 1151 * The first time we mount the root file system, 1152 * we need to mount 'ro', so We need to ignore 1153 * 'rw' and 'noro' mount options. 1154 */ 1155 continue; 1156 } 1157 name_arg = strdup(name, M_MOUNT); 1158 val_arg = NULL; 1159 if (val != NULL) 1160 val_arg = strdup(val, M_MOUNT); 1161 1162 ma = mount_arg(ma, name_arg, val_arg, 1163 (val_arg != NULL ? -1 : 0)); 1164 } 1165 free(opts, M_MOUNT); 1166 return (ma); 1167 } 1168