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/fcntl.h> 49#include <sys/jail.h> 50#include <sys/kernel.h> 51#include <sys/malloc.h> 52#include <sys/mdioctl.h> 53#include <sys/mount.h> 54#include <sys/mutex.h> 55#include <sys/namei.h> 56#include <sys/priv.h> 57#include <sys/proc.h> 58#include <sys/filedesc.h> 59#include <sys/reboot.h> 60#include <sys/sbuf.h> 61#include <sys/stat.h> 62#include <sys/syscallsubr.h> 63#include <sys/sysproto.h> 64#include <sys/sx.h> 65#include <sys/sysctl.h> 66#include <sys/sysent.h> 67#include <sys/systm.h> 68#include <sys/vnode.h> 69 70#include <geom/geom.h> 71 72/* 73 * The root filesystem is detailed in the kernel environment variable 74 * vfs.root.mountfrom, which is expected to be in the general format 75 * 76 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 77 * vfsname := the name of a VFS known to the kernel and capable 78 * of being mounted as root 79 * path := disk device name or other data used by the filesystem 80 * to locate its physical store 81 * 82 * If the environment variable vfs.root.mountfrom is a space separated list, 83 * each list element is tried in turn and the root filesystem will be mounted 84 * from the first one that succeeds. 85 * 86 * The environment variable vfs.root.mountfrom.options is a comma delimited 87 * set of string mount options. These mount options must be parseable 88 * by nmount() in the kernel. 89 */ 90 91static int parse_mount(char **); 92static struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 93static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS); 94static void vfs_mountroot_wait(void); 95static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev); 96 97/* 98 * The vnode of the system's root (/ in the filesystem, without chroot 99 * active.) 100 */ 101struct vnode *rootvnode; 102 103/* 104 * Mount of the system's /dev. 105 */ 106struct mount *rootdevmp; 107 108char *rootdevnames[2] = {NULL, NULL}; 109 110struct mtx root_holds_mtx; 111MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 112 113static TAILQ_HEAD(, root_hold_token) root_holds = 114 TAILQ_HEAD_INITIALIZER(root_holds); 115 116enum action { 117 A_CONTINUE, 118 A_PANIC, 119 A_REBOOT, 120 A_RETRY 121}; 122 123enum rh_flags { 124 RH_FREE, 125 RH_ALLOC, 126 RH_ARG, 127}; 128 129static enum action root_mount_onfail = A_CONTINUE; 130 131static int root_mount_mddev; 132static int root_mount_complete; 133 134/* By default wait up to 3 seconds for devices to appear. */ 135static int root_mount_timeout = 3; 136TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 137 138static int root_mount_always_wait = 0; 139SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN, 140 &root_mount_always_wait, 0, 141 "Wait for root mount holds even if the root device already exists"); 142 143SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold, 144 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 145 NULL, 0, sysctl_vfs_root_mount_hold, "A", 146 "List of root mount hold tokens"); 147 148static int 149sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS) 150{ 151 struct sbuf sb; 152 struct root_hold_token *h; 153 int error; 154 155 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 156 157 mtx_lock(&root_holds_mtx); 158 TAILQ_FOREACH(h, &root_holds, list) { 159 if (h != TAILQ_FIRST(&root_holds)) 160 sbuf_putc(&sb, ' '); 161 sbuf_printf(&sb, "%s", h->who); 162 } 163 mtx_unlock(&root_holds_mtx); 164 165 error = sbuf_finish(&sb); 166 if (error == 0) 167 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 168 sbuf_delete(&sb); 169 return (error); 170} 171 172struct root_hold_token * 173root_mount_hold(const char *identifier) 174{ 175 struct root_hold_token *h; 176 177 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 178 h->flags = RH_ALLOC; 179 h->who = identifier; 180 mtx_lock(&root_holds_mtx); 181 TSHOLD("root mount"); 182 TAILQ_INSERT_TAIL(&root_holds, h, list); 183 mtx_unlock(&root_holds_mtx); 184 return (h); 185} 186 187void 188root_mount_hold_token(const char *identifier, struct root_hold_token *h) 189{ 190#ifdef INVARIANTS 191 struct root_hold_token *t; 192#endif 193 194 h->flags = RH_ARG; 195 h->who = identifier; 196 mtx_lock(&root_holds_mtx); 197#ifdef INVARIANTS 198 TAILQ_FOREACH(t, &root_holds, list) { 199 if (t == h) { 200 panic("Duplicate mount hold by '%s' on %p", 201 identifier, h); 202 } 203 } 204#endif 205 TSHOLD("root mount"); 206 TAILQ_INSERT_TAIL(&root_holds, h, list); 207 mtx_unlock(&root_holds_mtx); 208} 209 210void 211root_mount_rel(struct root_hold_token *h) 212{ 213 214 if (h == NULL || h->flags == RH_FREE) 215 return; 216 217 mtx_lock(&root_holds_mtx); 218 TAILQ_REMOVE(&root_holds, h, list); 219 TSRELEASE("root mount"); 220 wakeup(&root_holds); 221 mtx_unlock(&root_holds_mtx); 222 if (h->flags == RH_ALLOC) { 223 free(h, M_DEVBUF); 224 } else 225 h->flags = RH_FREE; 226} 227 228int 229root_mounted(void) 230{ 231 232 /* No mutex is acquired here because int stores are atomic. */ 233 return (root_mount_complete); 234} 235 236static void 237set_rootvnode(void) 238{ 239 struct proc *p; 240 241 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 242 panic("Cannot find root vnode"); 243 244 VOP_UNLOCK(rootvnode, 0); 245 246 p = curthread->td_proc; 247 FILEDESC_XLOCK(p->p_fd); 248 249 if (p->p_fd->fd_cdir != NULL) 250 vrele(p->p_fd->fd_cdir); 251 p->p_fd->fd_cdir = rootvnode; 252 VREF(rootvnode); 253 254 if (p->p_fd->fd_rdir != NULL) 255 vrele(p->p_fd->fd_rdir); 256 p->p_fd->fd_rdir = rootvnode; 257 VREF(rootvnode); 258 259 FILEDESC_XUNLOCK(p->p_fd); 260} 261 262static int 263vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 264{ 265 struct vfsoptlist *opts; 266 struct vfsconf *vfsp; 267 struct mount *mp; 268 int error; 269 270 *mpp = NULL; 271 272 if (rootdevmp != NULL) { 273 /* 274 * Already have /dev; this happens during rerooting. 275 */ 276 error = vfs_busy(rootdevmp, 0); 277 if (error != 0) 278 return (error); 279 *mpp = rootdevmp; 280 } else { 281 vfsp = vfs_byname("devfs"); 282 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 283 if (vfsp == NULL) 284 return (ENOENT); 285 286 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 287 288 error = VFS_MOUNT(mp); 289 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 290 if (error) 291 return (error); 292 293 error = VFS_STATFS(mp, &mp->mnt_stat); 294 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error)); 295 if (error) 296 return (error); 297 298 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 299 TAILQ_INIT(opts); 300 mp->mnt_opt = opts; 301 302 mtx_lock(&mountlist_mtx); 303 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 304 mtx_unlock(&mountlist_mtx); 305 306 *mpp = mp; 307 rootdevmp = mp; 308 } 309 310 set_rootvnode(); 311 312 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 313 if (error) 314 printf("kern_symlink /dev -> / returns %d\n", error); 315 316 return (error); 317} 318 319static void 320vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 321{ 322 struct nameidata nd; 323 struct mount *mporoot, *mpnroot; 324 struct vnode *vp, *vporoot, *vpdevfs; 325 char *fspath; 326 int error; 327 328 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 329 330 /* Shuffle the mountlist. */ 331 mtx_lock(&mountlist_mtx); 332 mporoot = TAILQ_FIRST(&mountlist); 333 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 334 if (mporoot != mpdevfs) { 335 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 336 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 337 } 338 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 339 mtx_unlock(&mountlist_mtx); 340 341 cache_purgevfs(mporoot, true); 342 if (mporoot != mpdevfs) 343 cache_purgevfs(mpdevfs, true); 344 345 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot); 346 347 VI_LOCK(vporoot); 348 vporoot->v_iflag &= ~VI_MOUNT; 349 VI_UNLOCK(vporoot); 350 vporoot->v_mountedhere = NULL; 351 mporoot->mnt_flag &= ~MNT_ROOTFS; 352 mporoot->mnt_vnodecovered = NULL; 353 vput(vporoot); 354 355 /* Set up the new rootvnode, and purge the cache */ 356 mpnroot->mnt_vnodecovered = NULL; 357 set_rootvnode(); 358 cache_purgevfs(rootvnode->v_mount, true); 359 360 if (mporoot != mpdevfs) { 361 /* Remount old root under /.mount or /mnt */ 362 fspath = "/.mount"; 363 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 364 fspath, td); 365 error = namei(&nd); 366 if (error) { 367 NDFREE(&nd, NDF_ONLY_PNBUF); 368 fspath = "/mnt"; 369 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 370 fspath, td); 371 error = namei(&nd); 372 } 373 if (!error) { 374 vp = nd.ni_vp; 375 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 376 if (!error) 377 error = vinvalbuf(vp, V_SAVE, 0, 0); 378 if (!error) { 379 cache_purge(vp); 380 mporoot->mnt_vnodecovered = vp; 381 vp->v_mountedhere = mporoot; 382 strlcpy(mporoot->mnt_stat.f_mntonname, 383 fspath, MNAMELEN); 384 VOP_UNLOCK(vp, 0); 385 } else 386 vput(vp); 387 } 388 NDFREE(&nd, NDF_ONLY_PNBUF); 389 390 if (error) 391 printf("mountroot: unable to remount previous root " 392 "under /.mount or /mnt (error %d)\n", error); 393 } 394 395 /* Remount devfs under /dev */ 396 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 397 error = namei(&nd); 398 if (!error) { 399 vp = nd.ni_vp; 400 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 401 if (!error) 402 error = vinvalbuf(vp, V_SAVE, 0, 0); 403 if (!error) { 404 vpdevfs = mpdevfs->mnt_vnodecovered; 405 if (vpdevfs != NULL) { 406 cache_purge(vpdevfs); 407 vpdevfs->v_mountedhere = NULL; 408 vrele(vpdevfs); 409 } 410 mpdevfs->mnt_vnodecovered = vp; 411 vp->v_mountedhere = mpdevfs; 412 VOP_UNLOCK(vp, 0); 413 } else 414 vput(vp); 415 } 416 if (error) 417 printf("mountroot: unable to remount devfs under /dev " 418 "(error %d)\n", error); 419 NDFREE(&nd, NDF_ONLY_PNBUF); 420 421 if (mporoot == mpdevfs) { 422 vfs_unbusy(mpdevfs); 423 /* Unlink the no longer needed /dev/dev -> / symlink */ 424 error = kern_unlinkat(td, AT_FDCWD, "/dev/dev", 425 UIO_SYSSPACE, 0, 0); 426 if (error) 427 printf("mountroot: unable to unlink /dev/dev " 428 "(error %d)\n", error); 429 } 430} 431 432/* 433 * Configuration parser. 434 */ 435 436/* Parser character classes. */ 437#define CC_WHITESPACE -1 438#define CC_NONWHITESPACE -2 439 440/* Parse errors. */ 441#define PE_EOF -1 442#define PE_EOL -2 443 444static __inline int 445parse_peek(char **conf) 446{ 447 448 return (**conf); 449} 450 451static __inline void 452parse_poke(char **conf, int c) 453{ 454 455 **conf = c; 456} 457 458static __inline void 459parse_advance(char **conf) 460{ 461 462 (*conf)++; 463} 464 465static int 466parse_skipto(char **conf, int mc) 467{ 468 int c, match; 469 470 while (1) { 471 c = parse_peek(conf); 472 if (c == 0) 473 return (PE_EOF); 474 switch (mc) { 475 case CC_WHITESPACE: 476 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 477 break; 478 case CC_NONWHITESPACE: 479 if (c == '\n') 480 return (PE_EOL); 481 match = (c != ' ' && c != '\t') ? 1 : 0; 482 break; 483 default: 484 match = (c == mc) ? 1 : 0; 485 break; 486 } 487 if (match) 488 break; 489 parse_advance(conf); 490 } 491 return (0); 492} 493 494static int 495parse_token(char **conf, char **tok) 496{ 497 char *p; 498 size_t len; 499 int error; 500 501 *tok = NULL; 502 error = parse_skipto(conf, CC_NONWHITESPACE); 503 if (error) 504 return (error); 505 p = *conf; 506 error = parse_skipto(conf, CC_WHITESPACE); 507 len = *conf - p; 508 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 509 bcopy(p, *tok, len); 510 return (0); 511} 512 513static void 514parse_dir_ask_printenv(const char *var) 515{ 516 char *val; 517 518 val = kern_getenv(var); 519 if (val != NULL) { 520 printf(" %s=%s\n", var, val); 521 freeenv(val); 522 } 523} 524 525static int 526parse_dir_ask(char **conf) 527{ 528 char name[80]; 529 char *mnt; 530 int error; 531 532 vfs_mountroot_wait(); 533 534 printf("\nLoader variables:\n"); 535 parse_dir_ask_printenv("vfs.root.mountfrom"); 536 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 537 538 printf("\nManual root filesystem specification:\n"); 539 printf(" <fstype>:<device> [options]\n"); 540 printf(" Mount <device> using filesystem <fstype>\n"); 541 printf(" and with the specified (optional) option list.\n"); 542 printf("\n"); 543 printf(" eg. ufs:/dev/da0s1a\n"); 544 printf(" zfs:zroot/ROOT/default\n"); 545 printf(" cd9660:/dev/cd0 ro\n"); 546 printf(" (which is equivalent to: "); 547 printf("mount -t cd9660 -o ro /dev/cd0 /)\n"); 548 printf("\n"); 549 printf(" ? List valid disk boot devices\n"); 550 printf(" . Yield 1 second (for background tasks)\n"); 551 printf(" <empty line> Abort manual input\n"); 552 553 do { 554 error = EINVAL; 555 printf("\nmountroot> "); 556 cngets(name, sizeof(name), GETS_ECHO); 557 if (name[0] == '\0') 558 break; 559 if (name[0] == '?' && name[1] == '\0') { 560 printf("\nList of GEOM managed disk devices:\n "); 561 g_dev_print(); 562 continue; 563 } 564 if (name[0] == '.' && name[1] == '\0') { 565 pause("rmask", hz); 566 continue; 567 } 568 mnt = name; 569 error = parse_mount(&mnt); 570 if (error == -1) 571 printf("Invalid file system specification.\n"); 572 } while (error != 0); 573 574 return (error); 575} 576 577static int 578parse_dir_md(char **conf) 579{ 580 struct stat sb; 581 struct thread *td; 582 struct md_ioctl *mdio; 583 char *path, *tok; 584 int error, fd, len; 585 586 td = curthread; 587 588 error = parse_token(conf, &tok); 589 if (error) 590 return (error); 591 592 len = strlen(tok); 593 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 594 path = (void *)(mdio + 1); 595 bcopy(tok, path, len); 596 free(tok, M_TEMP); 597 598 /* Get file status. */ 599 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 600 if (error) 601 goto out; 602 603 /* Open /dev/mdctl so that we can attach/detach. */ 604 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 605 O_RDWR, 0); 606 if (error) 607 goto out; 608 609 fd = td->td_retval[0]; 610 mdio->md_version = MDIOVERSION; 611 mdio->md_type = MD_VNODE; 612 613 if (root_mount_mddev != -1) { 614 mdio->md_unit = root_mount_mddev; 615 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 616 /* Ignore errors. We don't care. */ 617 root_mount_mddev = -1; 618 } 619 620 mdio->md_file = (void *)(mdio + 1); 621 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 622 mdio->md_mediasize = sb.st_size; 623 mdio->md_unit = 0; 624 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 625 if (error) 626 goto out; 627 628 if (mdio->md_unit > 9) { 629 printf("rootmount: too many md units\n"); 630 mdio->md_file = NULL; 631 mdio->md_options = 0; 632 mdio->md_mediasize = 0; 633 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 634 /* Ignore errors. We don't care. */ 635 error = ERANGE; 636 goto out; 637 } 638 639 root_mount_mddev = mdio->md_unit; 640 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 641 642 error = kern_close(td, fd); 643 644 out: 645 free(mdio, M_TEMP); 646 return (error); 647} 648 649static int 650parse_dir_onfail(char **conf) 651{ 652 char *action; 653 int error; 654 655 error = parse_token(conf, &action); 656 if (error) 657 return (error); 658 659 if (!strcmp(action, "continue")) 660 root_mount_onfail = A_CONTINUE; 661 else if (!strcmp(action, "panic")) 662 root_mount_onfail = A_PANIC; 663 else if (!strcmp(action, "reboot")) 664 root_mount_onfail = A_REBOOT; 665 else if (!strcmp(action, "retry")) 666 root_mount_onfail = A_RETRY; 667 else { 668 printf("rootmount: %s: unknown action\n", action); 669 error = EINVAL; 670 } 671 672 free(action, M_TEMP); 673 return (0); 674} 675 676static int 677parse_dir_timeout(char **conf) 678{ 679 char *tok, *endtok; 680 long secs; 681 int error; 682 683 error = parse_token(conf, &tok); 684 if (error) 685 return (error); 686 687 secs = strtol(tok, &endtok, 0); 688 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 689 if (!error) 690 root_mount_timeout = secs; 691 free(tok, M_TEMP); 692 return (error); 693} 694 695static int 696parse_directive(char **conf) 697{ 698 char *dir; 699 int error; 700 701 error = parse_token(conf, &dir); 702 if (error) 703 return (error); 704 705 if (strcmp(dir, ".ask") == 0) 706 error = parse_dir_ask(conf); 707 else if (strcmp(dir, ".md") == 0) 708 error = parse_dir_md(conf); 709 else if (strcmp(dir, ".onfail") == 0) 710 error = parse_dir_onfail(conf); 711 else if (strcmp(dir, ".timeout") == 0) 712 error = parse_dir_timeout(conf); 713 else { 714 printf("mountroot: invalid directive `%s'\n", dir); 715 /* Ignore the rest of the line. */ 716 (void)parse_skipto(conf, '\n'); 717 error = EINVAL; 718 } 719 free(dir, M_TEMP); 720 return (error); 721} 722 723static int 724parse_mount_dev_present(const char *dev) 725{ 726 struct nameidata nd; 727 int error; 728 729 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 730 error = namei(&nd); 731 if (!error) 732 vput(nd.ni_vp); 733 NDFREE(&nd, NDF_ONLY_PNBUF); 734 return (error != 0) ? 0 : 1; 735} 736 737#define ERRMSGL 255 738static int 739parse_mount(char **conf) 740{ 741 char *errmsg; 742 struct mntarg *ma; 743 char *dev, *fs, *opts, *tok; 744 int delay, error, timeout; 745 746 error = parse_token(conf, &tok); 747 if (error) 748 return (error); 749 fs = tok; 750 error = parse_skipto(&tok, ':'); 751 if (error) { 752 free(fs, M_TEMP); 753 return (error); 754 } 755 parse_poke(&tok, '\0'); 756 parse_advance(&tok); 757 dev = tok; 758 759 if (root_mount_mddev != -1) { 760 /* Handle substitution for the md unit number. */ 761 tok = strstr(dev, "md#"); 762 if (tok != NULL) 763 tok[2] = '0' + root_mount_mddev; 764 } 765 766 /* Parse options. */ 767 error = parse_token(conf, &tok); 768 opts = (error == 0) ? tok : NULL; 769 770 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 771 (opts != NULL) ? opts : ""); 772 773 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 774 775 if (vfs_byname(fs) == NULL) { 776 strlcpy(errmsg, "unknown file system", ERRMSGL); 777 error = ENOENT; 778 goto out; 779 } 780 781 error = vfs_mountroot_wait_if_neccessary(fs, dev); 782 if (error != 0) 783 goto out; 784 785 delay = hz / 10; 786 timeout = root_mount_timeout * hz; 787 788 for (;;) { 789 ma = NULL; 790 ma = mount_arg(ma, "fstype", fs, -1); 791 ma = mount_arg(ma, "fspath", "/", -1); 792 ma = mount_arg(ma, "from", dev, -1); 793 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 794 ma = mount_arg(ma, "ro", NULL, 0); 795 ma = parse_mountroot_options(ma, opts); 796 797 error = kernel_mount(ma, MNT_ROOTFS); 798 if (error == 0 || timeout <= 0) 799 break; 800 801 if (root_mount_timeout * hz == timeout || 802 (bootverbose && timeout % hz == 0)) { 803 printf("Mounting from %s:%s failed with error %d; " 804 "retrying for %d more second%s\n", fs, dev, error, 805 timeout / hz, (timeout / hz > 1) ? "s" : ""); 806 } 807 pause("rmretry", delay); 808 timeout -= delay; 809 } 810 out: 811 if (error) { 812 printf("Mounting from %s:%s failed with error %d", 813 fs, dev, error); 814 if (errmsg[0] != '\0') 815 printf(": %s", errmsg); 816 printf(".\n"); 817 } 818 free(fs, M_TEMP); 819 free(errmsg, M_TEMP); 820 if (opts != NULL) 821 free(opts, M_TEMP); 822 /* kernel_mount can return -1 on error. */ 823 return ((error < 0) ? EDOOFUS : error); 824} 825#undef ERRMSGL 826 827static int 828vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 829{ 830 struct mount *mp; 831 char *conf; 832 int error; 833 834 root_mount_mddev = -1; 835 836retry: 837 conf = sbuf_data(sb); 838 mp = TAILQ_NEXT(mpdevfs, mnt_list); 839 error = (mp == NULL) ? 0 : EDOOFUS; 840 root_mount_onfail = A_CONTINUE; 841 while (mp == NULL) { 842 error = parse_skipto(&conf, CC_NONWHITESPACE); 843 if (error == PE_EOL) { 844 parse_advance(&conf); 845 continue; 846 } 847 if (error < 0) 848 break; 849 switch (parse_peek(&conf)) { 850 case '#': 851 error = parse_skipto(&conf, '\n'); 852 break; 853 case '.': 854 error = parse_directive(&conf); 855 break; 856 default: 857 error = parse_mount(&conf); 858 if (error == -1) { 859 printf("mountroot: invalid file system " 860 "specification.\n"); 861 error = 0; 862 } 863 break; 864 } 865 if (error < 0) 866 break; 867 /* Ignore any trailing garbage on the line. */ 868 if (parse_peek(&conf) != '\n') { 869 printf("mountroot: advancing to next directive...\n"); 870 (void)parse_skipto(&conf, '\n'); 871 } 872 mp = TAILQ_NEXT(mpdevfs, mnt_list); 873 } 874 if (mp != NULL) 875 return (0); 876 877 /* 878 * We failed to mount (a new) root. 879 */ 880 switch (root_mount_onfail) { 881 case A_CONTINUE: 882 break; 883 case A_PANIC: 884 panic("mountroot: unable to (re-)mount root."); 885 /* NOTREACHED */ 886 case A_RETRY: 887 goto retry; 888 case A_REBOOT: 889 kern_reboot(RB_NOSYNC); 890 /* NOTREACHED */ 891 } 892 893 return (error); 894} 895 896static void 897vfs_mountroot_conf0(struct sbuf *sb) 898{ 899 char *s, *tok, *mnt, *opt; 900 int error; 901 902 sbuf_printf(sb, ".onfail panic\n"); 903 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 904 if (boothowto & RB_ASKNAME) 905 sbuf_printf(sb, ".ask\n"); 906#ifdef ROOTDEVNAME 907 if (boothowto & RB_DFLTROOT) 908 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 909#endif 910 if (boothowto & RB_CDROM) { 911 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 912 sbuf_printf(sb, ".timeout 0\n"); 913 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n"); 914 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 915 } 916 s = kern_getenv("vfs.root.mountfrom"); 917 if (s != NULL) { 918 opt = kern_getenv("vfs.root.mountfrom.options"); 919 tok = s; 920 error = parse_token(&tok, &mnt); 921 while (!error) { 922 sbuf_printf(sb, "%s %s\n", mnt, 923 (opt != NULL) ? opt : ""); 924 free(mnt, M_TEMP); 925 error = parse_token(&tok, &mnt); 926 } 927 if (opt != NULL) 928 freeenv(opt); 929 freeenv(s); 930 } 931 if (rootdevnames[0] != NULL) 932 sbuf_printf(sb, "%s\n", rootdevnames[0]); 933 if (rootdevnames[1] != NULL) 934 sbuf_printf(sb, "%s\n", rootdevnames[1]); 935#ifdef ROOTDEVNAME 936 if (!(boothowto & RB_DFLTROOT)) 937 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 938#endif 939 if (!(boothowto & RB_ASKNAME)) 940 sbuf_printf(sb, ".ask\n"); 941} 942 943static int 944vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 945{ 946 static char buf[128]; 947 struct nameidata nd; 948 off_t ofs; 949 ssize_t resid; 950 int error, flags, len; 951 952 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 953 flags = FREAD; 954 error = vn_open(&nd, &flags, 0, NULL); 955 if (error) 956 return (error); 957 958 NDFREE(&nd, NDF_ONLY_PNBUF); 959 ofs = 0; 960 len = sizeof(buf) - 1; 961 while (1) { 962 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 963 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 964 NOCRED, &resid, td); 965 if (error) 966 break; 967 if (resid == len) 968 break; 969 buf[len - resid] = 0; 970 sbuf_printf(sb, "%s", buf); 971 ofs += len - resid; 972 } 973 974 VOP_UNLOCK(nd.ni_vp, 0); 975 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 976 return (error); 977} 978 979static void 980vfs_mountroot_wait(void) 981{ 982 struct root_hold_token *h; 983 struct timeval lastfail; 984 int curfail; 985 986 TSENTER(); 987 988 curfail = 0; 989 while (1) { 990 g_waitidle(); 991 mtx_lock(&root_holds_mtx); 992 if (TAILQ_EMPTY(&root_holds)) { 993 mtx_unlock(&root_holds_mtx); 994 break; 995 } 996 if (ppsratecheck(&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 1008 TSEXIT(); 1009} 1010 1011static int 1012vfs_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 dev[0] == '\0' || root_mount_always_wait != 0) { 1023 vfs_mountroot_wait(); 1024 return (0); 1025 } 1026 1027 /* 1028 * Otherwise, no point in waiting if the device is already there. 1029 * Note that we must wait for GEOM to finish reconfiguring itself, 1030 * eg for geom_part(4) to finish tasting. 1031 */ 1032 g_waitidle(); 1033 if (parse_mount_dev_present(dev)) 1034 return (0); 1035 1036 /* 1037 * No luck. Let's wait. This code looks weird, but it's that way 1038 * to behave exactly as it used to work before. 1039 */ 1040 vfs_mountroot_wait(); 1041 printf("mountroot: waiting for device %s...\n", dev); 1042 delay = hz / 10; 1043 timeout = root_mount_timeout * hz; 1044 do { 1045 pause("rmdev", delay); 1046 timeout -= delay; 1047 } while (timeout > 0 && !parse_mount_dev_present(dev)); 1048 1049 if (timeout <= 0) 1050 return (ENODEV); 1051 1052 return (0); 1053} 1054 1055void 1056vfs_mountroot(void) 1057{ 1058 struct mount *mp; 1059 struct sbuf *sb; 1060 struct thread *td; 1061 time_t timebase; 1062 int error; 1063 1064 mtx_assert(&Giant, MA_NOTOWNED); 1065 1066 TSENTER(); 1067 1068 td = curthread; 1069 1070 sb = sbuf_new_auto(); 1071 vfs_mountroot_conf0(sb); 1072 sbuf_finish(sb); 1073 1074 error = vfs_mountroot_devfs(td, &mp); 1075 while (!error) { 1076 error = vfs_mountroot_parse(sb, mp); 1077 if (!error) { 1078 vfs_mountroot_shuffle(td, mp); 1079 sbuf_clear(sb); 1080 error = vfs_mountroot_readconf(td, sb); 1081 sbuf_finish(sb); 1082 } 1083 } 1084 1085 sbuf_delete(sb); 1086 1087 /* 1088 * Iterate over all currently mounted file systems and use 1089 * the time stamp found to check and/or initialize the RTC. 1090 * Call inittodr() only once and pass it the largest of the 1091 * timestamps we encounter. 1092 */ 1093 timebase = 0; 1094 mtx_lock(&mountlist_mtx); 1095 mp = TAILQ_FIRST(&mountlist); 1096 while (mp != NULL) { 1097 if (mp->mnt_time > timebase) 1098 timebase = mp->mnt_time; 1099 mp = TAILQ_NEXT(mp, mnt_list); 1100 } 1101 mtx_unlock(&mountlist_mtx); 1102 inittodr(timebase); 1103 1104 /* Keep prison0's root in sync with the global rootvnode. */ 1105 mtx_lock(&prison0.pr_mtx); 1106 prison0.pr_root = rootvnode; 1107 vref(prison0.pr_root); 1108 mtx_unlock(&prison0.pr_mtx); 1109 1110 mtx_lock(&root_holds_mtx); 1111 atomic_store_rel_int(&root_mount_complete, 1); 1112 wakeup(&root_mount_complete); 1113 mtx_unlock(&root_holds_mtx); 1114 1115 EVENTHANDLER_INVOKE(mountroot); 1116 1117 TSEXIT(); 1118} 1119 1120static struct mntarg * 1121parse_mountroot_options(struct mntarg *ma, const char *options) 1122{ 1123 char *p; 1124 char *name, *name_arg; 1125 char *val, *val_arg; 1126 char *opts; 1127 1128 if (options == NULL || options[0] == '\0') 1129 return (ma); 1130 1131 p = opts = strdup(options, M_MOUNT); 1132 if (opts == NULL) { 1133 return (ma); 1134 } 1135 1136 while((name = strsep(&p, ",")) != NULL) { 1137 if (name[0] == '\0') 1138 break; 1139 1140 val = strchr(name, '='); 1141 if (val != NULL) { 1142 *val = '\0'; 1143 ++val; 1144 } 1145 if( strcmp(name, "rw") == 0 || 1146 strcmp(name, "noro") == 0) { 1147 /* 1148 * The first time we mount the root file system, 1149 * we need to mount 'ro', so We need to ignore 1150 * 'rw' and 'noro' mount options. 1151 */ 1152 continue; 1153 } 1154 name_arg = strdup(name, M_MOUNT); 1155 val_arg = NULL; 1156 if (val != NULL) 1157 val_arg = strdup(val, M_MOUNT); 1158 1159 ma = mount_arg(ma, name_arg, val_arg, 1160 (val_arg != NULL ? -1 : 0)); 1161 } 1162 free(opts, M_MOUNT); 1163 return (ma); 1164} 1165