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 struct proc *p; 241 242 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 243 panic("set_rootvnode: Cannot find root vnode"); 244 245 VOP_UNLOCK(rootvnode); 246 247 p = curthread->td_proc; 248 FILEDESC_XLOCK(p->p_fd); 249 250 if (p->p_fd->fd_cdir != NULL) 251 vrele(p->p_fd->fd_cdir); 252 p->p_fd->fd_cdir = rootvnode; 253 VREF(rootvnode); 254 255 if (p->p_fd->fd_rdir != NULL) 256 vrele(p->p_fd->fd_rdir); 257 p->p_fd->fd_rdir = rootvnode; 258 VREF(rootvnode); 259 260 FILEDESC_XUNLOCK(p->p_fd); 261 } 262 263 static int 264 vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 265 { 266 struct vfsoptlist *opts; 267 struct vfsconf *vfsp; 268 struct mount *mp; 269 int error; 270 271 *mpp = NULL; 272 273 if (rootdevmp != NULL) { 274 /* 275 * Already have /dev; this happens during rerooting. 276 */ 277 error = vfs_busy(rootdevmp, 0); 278 if (error != 0) 279 return (error); 280 *mpp = rootdevmp; 281 } else { 282 vfsp = vfs_byname("devfs"); 283 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 284 if (vfsp == NULL) 285 return (ENOENT); 286 287 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 288 289 error = VFS_MOUNT(mp); 290 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 291 if (error) 292 return (error); 293 294 error = VFS_STATFS(mp, &mp->mnt_stat); 295 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error)); 296 if (error) 297 return (error); 298 299 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 300 TAILQ_INIT(opts); 301 mp->mnt_opt = opts; 302 303 mtx_lock(&mountlist_mtx); 304 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 305 mtx_unlock(&mountlist_mtx); 306 307 *mpp = mp; 308 rootdevmp = mp; 309 vfs_op_exit(mp); 310 } 311 312 set_rootvnode(); 313 314 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 315 if (error) 316 printf("kern_symlink /dev -> / returns %d\n", error); 317 318 return (error); 319 } 320 321 static void 322 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 323 { 324 struct nameidata nd; 325 struct mount *mporoot, *mpnroot; 326 struct vnode *vp, *vporoot, *vpdevfs; 327 char *fspath; 328 int error; 329 330 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 331 332 /* Shuffle the mountlist. */ 333 mtx_lock(&mountlist_mtx); 334 mporoot = TAILQ_FIRST(&mountlist); 335 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 336 if (mporoot != mpdevfs) { 337 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 338 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 339 } 340 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 341 mtx_unlock(&mountlist_mtx); 342 343 cache_purgevfs(mporoot, true); 344 if (mporoot != mpdevfs) 345 cache_purgevfs(mpdevfs, true); 346 347 if (VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot)) 348 panic("vfs_mountroot_shuffle: Cannot find root vnode"); 349 350 VI_LOCK(vporoot); 351 vporoot->v_iflag &= ~VI_MOUNT; 352 VI_UNLOCK(vporoot); 353 vporoot->v_mountedhere = NULL; 354 mporoot->mnt_flag &= ~MNT_ROOTFS; 355 mporoot->mnt_vnodecovered = NULL; 356 vput(vporoot); 357 358 /* Set up the new rootvnode, and purge the cache */ 359 mpnroot->mnt_vnodecovered = NULL; 360 set_rootvnode(); 361 cache_purgevfs(rootvnode->v_mount, true); 362 363 if (mporoot != mpdevfs) { 364 /* Remount old root under /.mount or /mnt */ 365 fspath = "/.mount"; 366 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 367 fspath, td); 368 error = namei(&nd); 369 if (error) { 370 NDFREE(&nd, NDF_ONLY_PNBUF); 371 fspath = "/mnt"; 372 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 373 fspath, td); 374 error = namei(&nd); 375 } 376 if (!error) { 377 vp = nd.ni_vp; 378 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 379 if (!error) 380 error = vinvalbuf(vp, V_SAVE, 0, 0); 381 if (!error) { 382 cache_purge(vp); 383 mporoot->mnt_vnodecovered = vp; 384 vp->v_mountedhere = mporoot; 385 strlcpy(mporoot->mnt_stat.f_mntonname, 386 fspath, MNAMELEN); 387 VOP_UNLOCK(vp); 388 } else 389 vput(vp); 390 } 391 NDFREE(&nd, NDF_ONLY_PNBUF); 392 393 if (error) 394 printf("mountroot: unable to remount previous root " 395 "under /.mount or /mnt (error %d)\n", error); 396 } 397 398 /* Remount devfs under /dev */ 399 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 400 error = namei(&nd); 401 if (!error) { 402 vp = nd.ni_vp; 403 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 404 if (!error) 405 error = vinvalbuf(vp, V_SAVE, 0, 0); 406 if (!error) { 407 vpdevfs = mpdevfs->mnt_vnodecovered; 408 if (vpdevfs != NULL) { 409 cache_purge(vpdevfs); 410 vpdevfs->v_mountedhere = NULL; 411 vrele(vpdevfs); 412 } 413 mpdevfs->mnt_vnodecovered = vp; 414 vp->v_mountedhere = mpdevfs; 415 VOP_UNLOCK(vp); 416 } else 417 vput(vp); 418 } 419 if (error) 420 printf("mountroot: unable to remount devfs under /dev " 421 "(error %d)\n", error); 422 NDFREE(&nd, NDF_ONLY_PNBUF); 423 424 if (mporoot == mpdevfs) { 425 vfs_unbusy(mpdevfs); 426 /* Unlink the no longer needed /dev/dev -> / symlink */ 427 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE, 428 UIO_SYSSPACE, 0, 0); 429 if (error) 430 printf("mountroot: unable to unlink /dev/dev " 431 "(error %d)\n", error); 432 } 433 } 434 435 /* 436 * Configuration parser. 437 */ 438 439 /* Parser character classes. */ 440 #define CC_WHITESPACE -1 441 #define CC_NONWHITESPACE -2 442 443 /* Parse errors. */ 444 #define PE_EOF -1 445 #define PE_EOL -2 446 447 static __inline int 448 parse_peek(char **conf) 449 { 450 451 return (**conf); 452 } 453 454 static __inline void 455 parse_poke(char **conf, int c) 456 { 457 458 **conf = c; 459 } 460 461 static __inline void 462 parse_advance(char **conf) 463 { 464 465 (*conf)++; 466 } 467 468 static int 469 parse_skipto(char **conf, int mc) 470 { 471 int c, match; 472 473 while (1) { 474 c = parse_peek(conf); 475 if (c == 0) 476 return (PE_EOF); 477 switch (mc) { 478 case CC_WHITESPACE: 479 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 480 break; 481 case CC_NONWHITESPACE: 482 if (c == '\n') 483 return (PE_EOL); 484 match = (c != ' ' && c != '\t') ? 1 : 0; 485 break; 486 default: 487 match = (c == mc) ? 1 : 0; 488 break; 489 } 490 if (match) 491 break; 492 parse_advance(conf); 493 } 494 return (0); 495 } 496 497 static int 498 parse_token(char **conf, char **tok) 499 { 500 char *p; 501 size_t len; 502 int error; 503 504 *tok = NULL; 505 error = parse_skipto(conf, CC_NONWHITESPACE); 506 if (error) 507 return (error); 508 p = *conf; 509 error = parse_skipto(conf, CC_WHITESPACE); 510 len = *conf - p; 511 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 512 bcopy(p, *tok, len); 513 return (0); 514 } 515 516 static void 517 parse_dir_ask_printenv(const char *var) 518 { 519 char *val; 520 521 val = kern_getenv(var); 522 if (val != NULL) { 523 printf(" %s=%s\n", var, val); 524 freeenv(val); 525 } 526 } 527 528 static int 529 parse_dir_ask(char **conf) 530 { 531 char name[80]; 532 char *mnt; 533 int error; 534 535 vfs_mountroot_wait(); 536 537 printf("\nLoader variables:\n"); 538 parse_dir_ask_printenv("vfs.root.mountfrom"); 539 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 540 541 printf("\nManual root filesystem specification:\n"); 542 printf(" <fstype>:<device> [options]\n"); 543 printf(" Mount <device> using filesystem <fstype>\n"); 544 printf(" and with the specified (optional) option list.\n"); 545 printf("\n"); 546 printf(" eg. ufs:/dev/da0s1a\n"); 547 printf(" zfs:zroot/ROOT/default\n"); 548 printf(" cd9660:/dev/cd0 ro\n"); 549 printf(" (which is equivalent to: "); 550 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 551 printf("\n"); 552 printf(" ? List valid disk boot devices\n"); 553 printf(" . Yield 1 second (for background tasks)\n"); 554 printf(" <empty line> Abort manual input\n"); 555 556 do { 557 error = EINVAL; 558 printf("\nmountroot> "); 559 cngets(name, sizeof(name), GETS_ECHO); 560 if (name[0] == '\0') 561 break; 562 if (name[0] == '?' && name[1] == '\0') { 563 printf("\nList of GEOM managed disk devices:\n "); 564 g_dev_print(); 565 continue; 566 } 567 if (name[0] == '.' && name[1] == '\0') { 568 pause("rmask", hz); 569 continue; 570 } 571 mnt = name; 572 error = parse_mount(&mnt); 573 if (error == -1) 574 printf("Invalid file system specification.\n"); 575 } while (error != 0); 576 577 return (error); 578 } 579 580 static int 581 parse_dir_md(char **conf) 582 { 583 struct stat sb; 584 struct thread *td; 585 struct md_ioctl *mdio; 586 char *path, *tok; 587 int error, fd, len; 588 589 td = curthread; 590 591 error = parse_token(conf, &tok); 592 if (error) 593 return (error); 594 595 len = strlen(tok); 596 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 597 path = (void *)(mdio + 1); 598 bcopy(tok, path, len); 599 free(tok, M_TEMP); 600 601 /* Get file status. */ 602 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 603 if (error) 604 goto out; 605 606 /* Open /dev/mdctl so that we can attach/detach. */ 607 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 608 O_RDWR, 0); 609 if (error) 610 goto out; 611 612 fd = td->td_retval[0]; 613 mdio->md_version = MDIOVERSION; 614 mdio->md_type = MD_VNODE; 615 616 if (root_mount_mddev != -1) { 617 mdio->md_unit = root_mount_mddev; 618 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 619 /* Ignore errors. We don't care. */ 620 root_mount_mddev = -1; 621 } 622 623 mdio->md_file = (void *)(mdio + 1); 624 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 625 mdio->md_mediasize = sb.st_size; 626 mdio->md_unit = 0; 627 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 628 if (error) 629 goto out; 630 631 if (mdio->md_unit > 9) { 632 printf("rootmount: too many md units\n"); 633 mdio->md_file = NULL; 634 mdio->md_options = 0; 635 mdio->md_mediasize = 0; 636 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 637 /* Ignore errors. We don't care. */ 638 error = ERANGE; 639 goto out; 640 } 641 642 root_mount_mddev = mdio->md_unit; 643 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 644 645 error = kern_close(td, fd); 646 647 out: 648 free(mdio, M_TEMP); 649 return (error); 650 } 651 652 static int 653 parse_dir_onfail(char **conf) 654 { 655 char *action; 656 int error; 657 658 error = parse_token(conf, &action); 659 if (error) 660 return (error); 661 662 if (!strcmp(action, "continue")) 663 root_mount_onfail = A_CONTINUE; 664 else if (!strcmp(action, "panic")) 665 root_mount_onfail = A_PANIC; 666 else if (!strcmp(action, "reboot")) 667 root_mount_onfail = A_REBOOT; 668 else if (!strcmp(action, "retry")) 669 root_mount_onfail = A_RETRY; 670 else { 671 printf("rootmount: %s: unknown action\n", action); 672 error = EINVAL; 673 } 674 675 free(action, M_TEMP); 676 return (0); 677 } 678 679 static int 680 parse_dir_timeout(char **conf) 681 { 682 char *tok, *endtok; 683 long secs; 684 int error; 685 686 error = parse_token(conf, &tok); 687 if (error) 688 return (error); 689 690 secs = strtol(tok, &endtok, 0); 691 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 692 if (!error) 693 root_mount_timeout = secs; 694 free(tok, M_TEMP); 695 return (error); 696 } 697 698 static int 699 parse_directive(char **conf) 700 { 701 char *dir; 702 int error; 703 704 error = parse_token(conf, &dir); 705 if (error) 706 return (error); 707 708 if (strcmp(dir, ".ask") == 0) 709 error = parse_dir_ask(conf); 710 else if (strcmp(dir, ".md") == 0) 711 error = parse_dir_md(conf); 712 else if (strcmp(dir, ".onfail") == 0) 713 error = parse_dir_onfail(conf); 714 else if (strcmp(dir, ".timeout") == 0) 715 error = parse_dir_timeout(conf); 716 else { 717 printf("mountroot: invalid directive `%s'\n", dir); 718 /* Ignore the rest of the line. */ 719 (void)parse_skipto(conf, '\n'); 720 error = EINVAL; 721 } 722 free(dir, M_TEMP); 723 return (error); 724 } 725 726 static int 727 parse_mount_dev_present(const char *dev) 728 { 729 struct nameidata nd; 730 int error; 731 732 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 733 error = namei(&nd); 734 if (!error) 735 vput(nd.ni_vp); 736 NDFREE(&nd, NDF_ONLY_PNBUF); 737 return (error != 0) ? 0 : 1; 738 } 739 740 #define ERRMSGL 255 741 static int 742 parse_mount(char **conf) 743 { 744 char *errmsg; 745 struct mntarg *ma; 746 char *dev, *fs, *opts, *tok; 747 int delay, error, timeout; 748 749 error = parse_token(conf, &tok); 750 if (error) 751 return (error); 752 fs = tok; 753 error = parse_skipto(&tok, ':'); 754 if (error) { 755 free(fs, M_TEMP); 756 return (error); 757 } 758 parse_poke(&tok, '\0'); 759 parse_advance(&tok); 760 dev = tok; 761 762 if (root_mount_mddev != -1) { 763 /* Handle substitution for the md unit number. */ 764 tok = strstr(dev, "md#"); 765 if (tok != NULL) 766 tok[2] = '0' + root_mount_mddev; 767 } 768 769 /* Parse options. */ 770 error = parse_token(conf, &tok); 771 opts = (error == 0) ? tok : NULL; 772 773 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 774 (opts != NULL) ? opts : ""); 775 776 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 777 778 if (vfs_byname(fs) == NULL) { 779 strlcpy(errmsg, "unknown file system", ERRMSGL); 780 error = ENOENT; 781 goto out; 782 } 783 784 error = vfs_mountroot_wait_if_neccessary(fs, dev); 785 if (error != 0) 786 goto out; 787 788 delay = hz / 10; 789 timeout = root_mount_timeout * hz; 790 791 for (;;) { 792 ma = NULL; 793 ma = mount_arg(ma, "fstype", fs, -1); 794 ma = mount_arg(ma, "fspath", "/", -1); 795 ma = mount_arg(ma, "from", dev, -1); 796 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 797 ma = mount_arg(ma, "ro", NULL, 0); 798 ma = parse_mountroot_options(ma, opts); 799 800 error = kernel_mount(ma, MNT_ROOTFS); 801 if (error == 0 || timeout <= 0) 802 break; 803 804 if (root_mount_timeout * hz == timeout || 805 (bootverbose && timeout % hz == 0)) { 806 printf("Mounting from %s:%s failed with error %d; " 807 "retrying for %d more second%s\n", fs, dev, error, 808 timeout / hz, (timeout / hz > 1) ? "s" : ""); 809 } 810 pause("rmretry", delay); 811 timeout -= delay; 812 } 813 out: 814 if (error) { 815 printf("Mounting from %s:%s failed with error %d", 816 fs, dev, error); 817 if (errmsg[0] != '\0') 818 printf(": %s", errmsg); 819 printf(".\n"); 820 } 821 free(fs, M_TEMP); 822 free(errmsg, M_TEMP); 823 if (opts != NULL) 824 free(opts, M_TEMP); 825 /* kernel_mount can return -1 on error. */ 826 return ((error < 0) ? EDOOFUS : error); 827 } 828 #undef ERRMSGL 829 830 static int 831 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 832 { 833 struct mount *mp; 834 char *conf; 835 int error; 836 837 root_mount_mddev = -1; 838 839 retry: 840 conf = sbuf_data(sb); 841 mp = TAILQ_NEXT(mpdevfs, mnt_list); 842 error = (mp == NULL) ? 0 : EDOOFUS; 843 root_mount_onfail = A_CONTINUE; 844 while (mp == NULL) { 845 error = parse_skipto(&conf, CC_NONWHITESPACE); 846 if (error == PE_EOL) { 847 parse_advance(&conf); 848 continue; 849 } 850 if (error < 0) 851 break; 852 switch (parse_peek(&conf)) { 853 case '#': 854 error = parse_skipto(&conf, '\n'); 855 break; 856 case '.': 857 error = parse_directive(&conf); 858 break; 859 default: 860 error = parse_mount(&conf); 861 if (error == -1) { 862 printf("mountroot: invalid file system " 863 "specification.\n"); 864 error = 0; 865 } 866 break; 867 } 868 if (error < 0) 869 break; 870 /* Ignore any trailing garbage on the line. */ 871 if (parse_peek(&conf) != '\n') { 872 printf("mountroot: advancing to next directive...\n"); 873 (void)parse_skipto(&conf, '\n'); 874 } 875 mp = TAILQ_NEXT(mpdevfs, mnt_list); 876 } 877 if (mp != NULL) 878 return (0); 879 880 /* 881 * We failed to mount (a new) root. 882 */ 883 switch (root_mount_onfail) { 884 case A_CONTINUE: 885 break; 886 case A_PANIC: 887 panic("mountroot: unable to (re-)mount root."); 888 /* NOTREACHED */ 889 case A_RETRY: 890 goto retry; 891 case A_REBOOT: 892 kern_reboot(RB_NOSYNC); 893 /* NOTREACHED */ 894 } 895 896 return (error); 897 } 898 899 static void 900 vfs_mountroot_conf0(struct sbuf *sb) 901 { 902 char *s, *tok, *mnt, *opt; 903 int error; 904 905 sbuf_printf(sb, ".onfail panic\n"); 906 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 907 if (boothowto & RB_ASKNAME) 908 sbuf_printf(sb, ".ask\n"); 909 #ifdef ROOTDEVNAME 910 if (boothowto & RB_DFLTROOT) 911 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 912 #endif 913 if (boothowto & RB_CDROM) { 914 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 915 sbuf_printf(sb, ".timeout 0\n"); 916 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 917 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 918 } 919 s = kern_getenv("vfs.root.mountfrom"); 920 if (s != NULL) { 921 opt = kern_getenv("vfs.root.mountfrom.options"); 922 tok = s; 923 error = parse_token(&tok, &mnt); 924 while (!error) { 925 sbuf_printf(sb, "%s %s\n", mnt, 926 (opt != NULL) ? opt : ""); 927 free(mnt, M_TEMP); 928 error = parse_token(&tok, &mnt); 929 } 930 if (opt != NULL) 931 freeenv(opt); 932 freeenv(s); 933 } 934 if (rootdevnames[0] != NULL) 935 sbuf_printf(sb, "%s\n", rootdevnames[0]); 936 if (rootdevnames[1] != NULL) 937 sbuf_printf(sb, "%s\n", rootdevnames[1]); 938 #ifdef ROOTDEVNAME 939 if (!(boothowto & RB_DFLTROOT)) 940 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 941 #endif 942 if (!(boothowto & RB_ASKNAME)) 943 sbuf_printf(sb, ".ask\n"); 944 } 945 946 static int 947 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 948 { 949 static char buf[128]; 950 struct nameidata nd; 951 off_t ofs; 952 ssize_t resid; 953 int error, flags, len; 954 955 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 956 flags = FREAD; 957 error = vn_open(&nd, &flags, 0, NULL); 958 if (error) 959 return (error); 960 961 NDFREE(&nd, NDF_ONLY_PNBUF); 962 ofs = 0; 963 len = sizeof(buf) - 1; 964 while (1) { 965 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 966 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 967 NOCRED, &resid, td); 968 if (error) 969 break; 970 if (resid == len) 971 break; 972 buf[len - resid] = 0; 973 sbuf_printf(sb, "%s", buf); 974 ofs += len - resid; 975 } 976 977 VOP_UNLOCK(nd.ni_vp); 978 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 979 return (error); 980 } 981 982 static void 983 vfs_mountroot_wait(void) 984 { 985 struct root_hold_token *h; 986 struct timeval lastfail; 987 int curfail; 988 989 TSENTER(); 990 991 curfail = 0; 992 while (1) { 993 g_waitidle(); 994 mtx_lock(&root_holds_mtx); 995 if (TAILQ_EMPTY(&root_holds)) { 996 mtx_unlock(&root_holds_mtx); 997 break; 998 } 999 if (ppsratecheck(&lastfail, &curfail, 1)) { 1000 printf("Root mount waiting for:"); 1001 TAILQ_FOREACH(h, &root_holds, list) 1002 printf(" %s", h->who); 1003 printf("\n"); 1004 } 1005 TSWAIT("root mount"); 1006 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 1007 hz); 1008 TSUNWAIT("root mount"); 1009 } 1010 1011 TSEXIT(); 1012 } 1013 1014 static int 1015 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev) 1016 { 1017 int delay, timeout; 1018 1019 /* 1020 * In case of ZFS and NFS we don't have a way to wait for 1021 * specific device. Also do the wait if the user forced that 1022 * behaviour by setting vfs.root_mount_always_wait=1. 1023 */ 1024 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL || 1025 dev[0] == '\0' || root_mount_always_wait != 0) { 1026 vfs_mountroot_wait(); 1027 return (0); 1028 } 1029 1030 /* 1031 * Otherwise, no point in waiting if the device is already there. 1032 * Note that we must wait for GEOM to finish reconfiguring itself, 1033 * eg for geom_part(4) to finish tasting. 1034 */ 1035 g_waitidle(); 1036 if (parse_mount_dev_present(dev)) 1037 return (0); 1038 1039 /* 1040 * No luck. Let's wait. This code looks weird, but it's that way 1041 * to behave exactly as it used to work before. 1042 */ 1043 vfs_mountroot_wait(); 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 || 1149 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