vfs_mountroot.c revision 287107
11573Srgrimes/*- 21573Srgrimes * Copyright (c) 2010 Marcel Moolenaar 31573Srgrimes * Copyright (c) 1999-2004 Poul-Henning Kamp 41573Srgrimes * Copyright (c) 1999 Michael Smith 51573Srgrimes * Copyright (c) 1989, 1993 61573Srgrimes * The Regents of the University of California. All rights reserved. 71573Srgrimes * (c) UNIX System Laboratories, Inc. 81573Srgrimes * All or some portions of this file are derived from material licensed 91573Srgrimes * to the University of California by American Telephone and Telegraph 101573Srgrimes * Co. or Unix System Laboratories, Inc. and are reproduced herein with 111573Srgrimes * the permission of UNIX System Laboratories, Inc. 121573Srgrimes * 131573Srgrimes * Redistribution and use in source and binary forms, with or without 141573Srgrimes * modification, are permitted provided that the following conditions 151573Srgrimes * are met: 16249808Semaste * 1. Redistributions of source code must retain the above copyright 171573Srgrimes * notice, this list of conditions and the following disclaimer. 181573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 191573Srgrimes * notice, this list of conditions and the following disclaimer in the 201573Srgrimes * documentation and/or other materials provided with the distribution. 211573Srgrimes * 4. Neither the name of the University nor the names of its contributors 221573Srgrimes * may be used to endorse or promote products derived from this software 231573Srgrimes * without specific prior written permission. 241573Srgrimes * 251573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 261573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 271573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 281573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 291573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 301573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 311573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 321573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 331573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 341573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 351573Srgrimes * SUCH DAMAGE. 3692986Sobrien */ 3792986Sobrien 381573Srgrimes#include "opt_rootdevname.h" 3971579Sdeischen 401573Srgrimes#include <sys/cdefs.h> 411573Srgrimes__FBSDID("$FreeBSD: head/sys/kern/vfs_mountroot.c 287107 2015-08-24 13:18:13Z trasz $"); 421573Srgrimes 431573Srgrimes#include <sys/param.h> 441573Srgrimes#include <sys/conf.h> 4571579Sdeischen#include <sys/cons.h> 461573Srgrimes#include <sys/fcntl.h> 47150040Sstefanf#include <sys/jail.h> 48150040Sstefanf#include <sys/kernel.h> 49150040Sstefanf#include <sys/malloc.h> 501573Srgrimes#include <sys/mdioctl.h> 511573Srgrimes#include <sys/mount.h> 521573Srgrimes#include <sys/mutex.h> 531573Srgrimes#include <sys/namei.h> 541573Srgrimes#include <sys/priv.h> 5571579Sdeischen#include <sys/proc.h> 561573Srgrimes#include <sys/filedesc.h> 571573Srgrimes#include <sys/reboot.h> 58249810Semaste#include <sys/sbuf.h> 591573Srgrimes#include <sys/stat.h> 6092889Sobrien#include <sys/syscallsubr.h> 6192889Sobrien#include <sys/sysproto.h> 621573Srgrimes#include <sys/sx.h> 631573Srgrimes#include <sys/sysctl.h> 641573Srgrimes#include <sys/sysent.h> 651573Srgrimes#include <sys/systm.h> 661573Srgrimes#include <sys/vnode.h> 671573Srgrimes 681573Srgrimes#include <geom/geom.h> 691573Srgrimes 701573Srgrimes/* 711573Srgrimes * The root filesystem is detailed in the kernel environment variable 721573Srgrimes * vfs.root.mountfrom, which is expected to be in the general format 731573Srgrimes * 741573Srgrimes * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 751573Srgrimes * vfsname := the name of a VFS known to the kernel and capable 761573Srgrimes * of being mounted as root 771573Srgrimes * path := disk device name or other data used by the filesystem 781573Srgrimes * to locate its physical store 791573Srgrimes * 801573Srgrimes * If the environment variable vfs.root.mountfrom is a space separated list, 811573Srgrimes * each list element is tried in turn and the root filesystem will be mounted 821573Srgrimes * from the first one that suceeds. 831573Srgrimes * 841573Srgrimes * The environment variable vfs.root.mountfrom.options is a comma delimited 851573Srgrimes * set of string mount options. These mount options must be parseable 861573Srgrimes * by nmount() in the kernel. 871573Srgrimes */ 881573Srgrimes 891573Srgrimesstatic int parse_mount(char **); 90249810Semastestatic struct mntarg *parse_mountroot_options(struct mntarg *, const char *); 911573Srgrimes 921573Srgrimes/* 931573Srgrimes * The vnode of the system's root (/ in the filesystem, without chroot 9471579Sdeischen * active.) 951573Srgrimes */ 961573Srgrimesstruct vnode *rootvnode; 971573Srgrimes 981573Srgrimes/* 991573Srgrimes * Mount of the system's /dev. 1001573Srgrimes */ 1011573Srgrimesstruct mount *rootdevmp; 1021573Srgrimes 1031573Srgrimeschar *rootdevnames[2] = {NULL, NULL}; 1041573Srgrimes 1051573Srgrimesstruct mtx root_holds_mtx; 1061573SrgrimesMTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF); 1071573Srgrimes 1081573Srgrimesstruct root_hold_token { 1091573Srgrimes const char *who; 1101573Srgrimes LIST_ENTRY(root_hold_token) list; 1111573Srgrimes}; 1121573Srgrimes 1131573Srgrimesstatic LIST_HEAD(, root_hold_token) root_holds = 1141573Srgrimes LIST_HEAD_INITIALIZER(root_holds); 1151573Srgrimes 1161573Srgrimesenum action { 117 A_CONTINUE, 118 A_PANIC, 119 A_REBOOT, 120 A_RETRY 121}; 122 123static enum action root_mount_onfail = A_CONTINUE; 124 125static int root_mount_mddev; 126static int root_mount_complete; 127 128/* By default wait up to 3 seconds for devices to appear. */ 129static int root_mount_timeout = 3; 130TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout); 131 132struct root_hold_token * 133root_mount_hold(const char *identifier) 134{ 135 struct root_hold_token *h; 136 137 if (root_mounted()) 138 return (NULL); 139 140 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 141 h->who = identifier; 142 mtx_lock(&root_holds_mtx); 143 LIST_INSERT_HEAD(&root_holds, h, list); 144 mtx_unlock(&root_holds_mtx); 145 return (h); 146} 147 148void 149root_mount_rel(struct root_hold_token *h) 150{ 151 152 if (h == NULL) 153 return; 154 mtx_lock(&root_holds_mtx); 155 LIST_REMOVE(h, list); 156 wakeup(&root_holds); 157 mtx_unlock(&root_holds_mtx); 158 free(h, M_DEVBUF); 159} 160 161int 162root_mounted(void) 163{ 164 165 /* No mutex is acquired here because int stores are atomic. */ 166 return (root_mount_complete); 167} 168 169void 170root_mount_wait(void) 171{ 172 173 /* 174 * Panic on an obvious deadlock - the function can't be called from 175 * a thread which is doing the whole SYSINIT stuff. 176 */ 177 KASSERT(curthread->td_proc->p_pid != 0, 178 ("root_mount_wait: cannot be called from the swapper thread")); 179 mtx_lock(&root_holds_mtx); 180 while (!root_mount_complete) { 181 msleep(&root_mount_complete, &root_holds_mtx, PZERO, "rootwait", 182 hz); 183 } 184 mtx_unlock(&root_holds_mtx); 185} 186 187static void 188set_rootvnode(void) 189{ 190 struct proc *p; 191 192 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 193 panic("Cannot find root vnode"); 194 195 VOP_UNLOCK(rootvnode, 0); 196 197 p = curthread->td_proc; 198 FILEDESC_XLOCK(p->p_fd); 199 200 if (p->p_fd->fd_cdir != NULL) 201 vrele(p->p_fd->fd_cdir); 202 p->p_fd->fd_cdir = rootvnode; 203 VREF(rootvnode); 204 205 if (p->p_fd->fd_rdir != NULL) 206 vrele(p->p_fd->fd_rdir); 207 p->p_fd->fd_rdir = rootvnode; 208 VREF(rootvnode); 209 210 FILEDESC_XUNLOCK(p->p_fd); 211} 212 213static int 214vfs_mountroot_devfs(struct thread *td, struct mount **mpp) 215{ 216 struct vfsoptlist *opts; 217 struct vfsconf *vfsp; 218 struct mount *mp; 219 int error; 220 221 *mpp = NULL; 222 223 vfsp = vfs_byname("devfs"); 224 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 225 if (vfsp == NULL) 226 return (ENOENT); 227 228 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 229 230 error = VFS_MOUNT(mp); 231 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 232 if (error) 233 return (error); 234 235 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 236 TAILQ_INIT(opts); 237 mp->mnt_opt = opts; 238 239 mtx_lock(&mountlist_mtx); 240 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 241 mtx_unlock(&mountlist_mtx); 242 243 *mpp = mp; 244 rootdevmp = mp; 245 set_rootvnode(); 246 247 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE); 248 if (error) 249 printf("kern_symlink /dev -> / returns %d\n", error); 250 251 return (error); 252} 253 254static int 255vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs) 256{ 257 struct nameidata nd; 258 struct mount *mporoot, *mpnroot; 259 struct vnode *vp, *vporoot, *vpdevfs; 260 char *fspath; 261 int error; 262 263 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list); 264 265 /* Shuffle the mountlist. */ 266 mtx_lock(&mountlist_mtx); 267 mporoot = TAILQ_FIRST(&mountlist); 268 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list); 269 if (mporoot != mpdevfs) { 270 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list); 271 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list); 272 } 273 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list); 274 mtx_unlock(&mountlist_mtx); 275 276 cache_purgevfs(mporoot); 277 if (mporoot != mpdevfs) 278 cache_purgevfs(mpdevfs); 279 280 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot); 281 282 VI_LOCK(vporoot); 283 vporoot->v_iflag &= ~VI_MOUNT; 284 VI_UNLOCK(vporoot); 285 vporoot->v_mountedhere = NULL; 286 mporoot->mnt_flag &= ~MNT_ROOTFS; 287 mporoot->mnt_vnodecovered = NULL; 288 vput(vporoot); 289 290 /* Set up the new rootvnode, and purge the cache */ 291 mpnroot->mnt_vnodecovered = NULL; 292 set_rootvnode(); 293 cache_purgevfs(rootvnode->v_mount); 294 295 if (mporoot != mpdevfs) { 296 /* Remount old root under /.mount or /mnt */ 297 fspath = "/.mount"; 298 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 299 fspath, td); 300 error = namei(&nd); 301 if (error) { 302 NDFREE(&nd, NDF_ONLY_PNBUF); 303 fspath = "/mnt"; 304 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, 305 fspath, td); 306 error = namei(&nd); 307 } 308 if (!error) { 309 vp = nd.ni_vp; 310 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 311 if (!error) 312 error = vinvalbuf(vp, V_SAVE, 0, 0); 313 if (!error) { 314 cache_purge(vp); 315 mporoot->mnt_vnodecovered = vp; 316 vp->v_mountedhere = mporoot; 317 strlcpy(mporoot->mnt_stat.f_mntonname, 318 fspath, MNAMELEN); 319 VOP_UNLOCK(vp, 0); 320 } else 321 vput(vp); 322 } 323 NDFREE(&nd, NDF_ONLY_PNBUF); 324 325 if (error && bootverbose) 326 printf("mountroot: unable to remount previous root " 327 "under /.mount or /mnt (error %d).\n", error); 328 } 329 330 /* Remount devfs under /dev */ 331 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 332 error = namei(&nd); 333 if (!error) { 334 vp = nd.ni_vp; 335 error = (vp->v_type == VDIR) ? 0 : ENOTDIR; 336 if (!error) 337 error = vinvalbuf(vp, V_SAVE, 0, 0); 338 if (!error) { 339 vpdevfs = mpdevfs->mnt_vnodecovered; 340 if (vpdevfs != NULL) { 341 cache_purge(vpdevfs); 342 vpdevfs->v_mountedhere = NULL; 343 vrele(vpdevfs); 344 } 345 mpdevfs->mnt_vnodecovered = vp; 346 vp->v_mountedhere = mpdevfs; 347 VOP_UNLOCK(vp, 0); 348 } else 349 vput(vp); 350 } 351 if (error && bootverbose) 352 printf("mountroot: unable to remount devfs under /dev " 353 "(error %d).\n", error); 354 NDFREE(&nd, NDF_ONLY_PNBUF); 355 356 if (mporoot == mpdevfs) { 357 vfs_unbusy(mpdevfs); 358 /* Unlink the no longer needed /dev/dev -> / symlink */ 359 error = kern_unlinkat(td, AT_FDCWD, "/dev/dev", 360 UIO_SYSSPACE, 0); 361 if (error && bootverbose) 362 printf("mountroot: unable to unlink /dev/dev " 363 "(error %d)\n", error); 364 } 365 366 return (0); 367} 368 369/* 370 * Configuration parser. 371 */ 372 373/* Parser character classes. */ 374#define CC_WHITESPACE -1 375#define CC_NONWHITESPACE -2 376 377/* Parse errors. */ 378#define PE_EOF -1 379#define PE_EOL -2 380 381static __inline int 382parse_peek(char **conf) 383{ 384 385 return (**conf); 386} 387 388static __inline void 389parse_poke(char **conf, int c) 390{ 391 392 **conf = c; 393} 394 395static __inline void 396parse_advance(char **conf) 397{ 398 399 (*conf)++; 400} 401 402static int 403parse_skipto(char **conf, int mc) 404{ 405 int c, match; 406 407 while (1) { 408 c = parse_peek(conf); 409 if (c == 0) 410 return (PE_EOF); 411 switch (mc) { 412 case CC_WHITESPACE: 413 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0; 414 break; 415 case CC_NONWHITESPACE: 416 if (c == '\n') 417 return (PE_EOL); 418 match = (c != ' ' && c != '\t') ? 1 : 0; 419 break; 420 default: 421 match = (c == mc) ? 1 : 0; 422 break; 423 } 424 if (match) 425 break; 426 parse_advance(conf); 427 } 428 return (0); 429} 430 431static int 432parse_token(char **conf, char **tok) 433{ 434 char *p; 435 size_t len; 436 int error; 437 438 *tok = NULL; 439 error = parse_skipto(conf, CC_NONWHITESPACE); 440 if (error) 441 return (error); 442 p = *conf; 443 error = parse_skipto(conf, CC_WHITESPACE); 444 len = *conf - p; 445 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO); 446 bcopy(p, *tok, len); 447 return (0); 448} 449 450static void 451parse_dir_ask_printenv(const char *var) 452{ 453 char *val; 454 455 val = kern_getenv(var); 456 if (val != NULL) { 457 printf(" %s=%s\n", var, val); 458 freeenv(val); 459 } 460} 461 462static int 463parse_dir_ask(char **conf) 464{ 465 char name[80]; 466 char *mnt; 467 int error; 468 469 printf("\nLoader variables:\n"); 470 parse_dir_ask_printenv("vfs.root.mountfrom"); 471 parse_dir_ask_printenv("vfs.root.mountfrom.options"); 472 473 printf("\nManual root filesystem specification:\n"); 474 printf(" <fstype>:<device> [options]\n"); 475 printf(" Mount <device> using filesystem <fstype>\n"); 476 printf(" and with the specified (optional) option list.\n"); 477 printf("\n"); 478 printf(" eg. ufs:/dev/da0s1a\n"); 479 printf(" zfs:tank\n"); 480 printf(" cd9660:/dev/acd0 ro\n"); 481 printf(" (which is equivalent to: "); 482 printf("mount -t cd9660 -o ro /dev/acd0 /)\n"); 483 printf("\n"); 484 printf(" ? List valid disk boot devices\n"); 485 printf(" . Yield 1 second (for background tasks)\n"); 486 printf(" <empty line> Abort manual input\n"); 487 488 do { 489 error = EINVAL; 490 printf("\nmountroot> "); 491 cngets(name, sizeof(name), GETS_ECHO); 492 if (name[0] == '\0') 493 break; 494 if (name[0] == '?' && name[1] == '\0') { 495 printf("\nList of GEOM managed disk devices:\n "); 496 g_dev_print(); 497 continue; 498 } 499 if (name[0] == '.' && name[1] == '\0') { 500 pause("rmask", hz); 501 continue; 502 } 503 mnt = name; 504 error = parse_mount(&mnt); 505 if (error == -1) 506 printf("Invalid file system specification.\n"); 507 } while (error != 0); 508 509 return (error); 510} 511 512static int 513parse_dir_md(char **conf) 514{ 515 struct stat sb; 516 struct thread *td; 517 struct md_ioctl *mdio; 518 char *path, *tok; 519 int error, fd, len; 520 521 td = curthread; 522 523 error = parse_token(conf, &tok); 524 if (error) 525 return (error); 526 527 len = strlen(tok); 528 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO); 529 path = (void *)(mdio + 1); 530 bcopy(tok, path, len); 531 free(tok, M_TEMP); 532 533 /* Get file status. */ 534 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL); 535 if (error) 536 goto out; 537 538 /* Open /dev/mdctl so that we can attach/detach. */ 539 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE, 540 O_RDWR, 0); 541 if (error) 542 goto out; 543 544 fd = td->td_retval[0]; 545 mdio->md_version = MDIOVERSION; 546 mdio->md_type = MD_VNODE; 547 548 if (root_mount_mddev != -1) { 549 mdio->md_unit = root_mount_mddev; 550 DROP_GIANT(); 551 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 552 PICKUP_GIANT(); 553 /* Ignore errors. We don't care. */ 554 root_mount_mddev = -1; 555 } 556 557 mdio->md_file = (void *)(mdio + 1); 558 mdio->md_options = MD_AUTOUNIT | MD_READONLY; 559 mdio->md_mediasize = sb.st_size; 560 mdio->md_unit = 0; 561 DROP_GIANT(); 562 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio); 563 PICKUP_GIANT(); 564 if (error) 565 goto out; 566 567 if (mdio->md_unit > 9) { 568 printf("rootmount: too many md units\n"); 569 mdio->md_file = NULL; 570 mdio->md_options = 0; 571 mdio->md_mediasize = 0; 572 DROP_GIANT(); 573 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio); 574 PICKUP_GIANT(); 575 /* Ignore errors. We don't care. */ 576 error = ERANGE; 577 goto out; 578 } 579 580 root_mount_mddev = mdio->md_unit; 581 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file); 582 583 error = kern_close(td, fd); 584 585 out: 586 free(mdio, M_TEMP); 587 return (error); 588} 589 590static int 591parse_dir_onfail(char **conf) 592{ 593 char *action; 594 int error; 595 596 error = parse_token(conf, &action); 597 if (error) 598 return (error); 599 600 if (!strcmp(action, "continue")) 601 root_mount_onfail = A_CONTINUE; 602 else if (!strcmp(action, "panic")) 603 root_mount_onfail = A_PANIC; 604 else if (!strcmp(action, "reboot")) 605 root_mount_onfail = A_REBOOT; 606 else if (!strcmp(action, "retry")) 607 root_mount_onfail = A_RETRY; 608 else { 609 printf("rootmount: %s: unknown action\n", action); 610 error = EINVAL; 611 } 612 613 free(action, M_TEMP); 614 return (0); 615} 616 617static int 618parse_dir_timeout(char **conf) 619{ 620 char *tok, *endtok; 621 long secs; 622 int error; 623 624 error = parse_token(conf, &tok); 625 if (error) 626 return (error); 627 628 secs = strtol(tok, &endtok, 0); 629 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0; 630 if (!error) 631 root_mount_timeout = secs; 632 free(tok, M_TEMP); 633 return (error); 634} 635 636static int 637parse_directive(char **conf) 638{ 639 char *dir; 640 int error; 641 642 error = parse_token(conf, &dir); 643 if (error) 644 return (error); 645 646 if (strcmp(dir, ".ask") == 0) 647 error = parse_dir_ask(conf); 648 else if (strcmp(dir, ".md") == 0) 649 error = parse_dir_md(conf); 650 else if (strcmp(dir, ".onfail") == 0) 651 error = parse_dir_onfail(conf); 652 else if (strcmp(dir, ".timeout") == 0) 653 error = parse_dir_timeout(conf); 654 else { 655 printf("mountroot: invalid directive `%s'\n", dir); 656 /* Ignore the rest of the line. */ 657 (void)parse_skipto(conf, '\n'); 658 error = EINVAL; 659 } 660 free(dir, M_TEMP); 661 return (error); 662} 663 664static int 665parse_mount_dev_present(const char *dev) 666{ 667 struct nameidata nd; 668 int error; 669 670 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread); 671 error = namei(&nd); 672 if (!error) 673 vput(nd.ni_vp); 674 NDFREE(&nd, NDF_ONLY_PNBUF); 675 return (error != 0) ? 0 : 1; 676} 677 678#define ERRMSGL 255 679static int 680parse_mount(char **conf) 681{ 682 char *errmsg; 683 struct mntarg *ma; 684 char *dev, *fs, *opts, *tok; 685 int delay, error, timeout; 686 687 error = parse_token(conf, &tok); 688 if (error) 689 return (error); 690 fs = tok; 691 error = parse_skipto(&tok, ':'); 692 if (error) { 693 free(fs, M_TEMP); 694 return (error); 695 } 696 parse_poke(&tok, '\0'); 697 parse_advance(&tok); 698 dev = tok; 699 700 if (root_mount_mddev != -1) { 701 /* Handle substitution for the md unit number. */ 702 tok = strstr(dev, "md#"); 703 if (tok != NULL) 704 tok[2] = '0' + root_mount_mddev; 705 } 706 707 /* Parse options. */ 708 error = parse_token(conf, &tok); 709 opts = (error == 0) ? tok : NULL; 710 711 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev, 712 (opts != NULL) ? opts : ""); 713 714 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO); 715 716 if (vfs_byname(fs) == NULL) { 717 strlcpy(errmsg, "unknown file system", ERRMSGL); 718 error = ENOENT; 719 goto out; 720 } 721 722 if (strcmp(fs, "zfs") != 0 && strstr(fs, "nfs") == NULL && 723 dev[0] != '\0' && !parse_mount_dev_present(dev)) { 724 printf("mountroot: waiting for device %s ...\n", dev); 725 delay = hz / 10; 726 timeout = root_mount_timeout * hz; 727 do { 728 pause("rmdev", delay); 729 timeout -= delay; 730 } while (timeout > 0 && !parse_mount_dev_present(dev)); 731 if (timeout <= 0) { 732 error = ENODEV; 733 goto out; 734 } 735 } 736 737 ma = NULL; 738 ma = mount_arg(ma, "fstype", fs, -1); 739 ma = mount_arg(ma, "fspath", "/", -1); 740 ma = mount_arg(ma, "from", dev, -1); 741 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL); 742 ma = mount_arg(ma, "ro", NULL, 0); 743 ma = parse_mountroot_options(ma, opts); 744 error = kernel_mount(ma, MNT_ROOTFS); 745 746 out: 747 if (error) { 748 printf("Mounting from %s:%s failed with error %d", 749 fs, dev, error); 750 if (errmsg[0] != '\0') 751 printf(": %s", errmsg); 752 printf(".\n"); 753 } 754 free(fs, M_TEMP); 755 free(errmsg, M_TEMP); 756 if (opts != NULL) 757 free(opts, M_TEMP); 758 /* kernel_mount can return -1 on error. */ 759 return ((error < 0) ? EDOOFUS : error); 760} 761#undef ERRMSGL 762 763static int 764vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs) 765{ 766 struct mount *mp; 767 char *conf; 768 int error; 769 770 root_mount_mddev = -1; 771 772retry: 773 conf = sbuf_data(sb); 774 mp = TAILQ_NEXT(mpdevfs, mnt_list); 775 error = (mp == NULL) ? 0 : EDOOFUS; 776 root_mount_onfail = A_CONTINUE; 777 while (mp == NULL) { 778 error = parse_skipto(&conf, CC_NONWHITESPACE); 779 if (error == PE_EOL) { 780 parse_advance(&conf); 781 continue; 782 } 783 if (error < 0) 784 break; 785 switch (parse_peek(&conf)) { 786 case '#': 787 error = parse_skipto(&conf, '\n'); 788 break; 789 case '.': 790 error = parse_directive(&conf); 791 break; 792 default: 793 error = parse_mount(&conf); 794 break; 795 } 796 if (error < 0) 797 break; 798 /* Ignore any trailing garbage on the line. */ 799 if (parse_peek(&conf) != '\n') { 800 printf("mountroot: advancing to next directive...\n"); 801 (void)parse_skipto(&conf, '\n'); 802 } 803 mp = TAILQ_NEXT(mpdevfs, mnt_list); 804 } 805 if (mp != NULL) 806 return (0); 807 808 /* 809 * We failed to mount (a new) root. 810 */ 811 switch (root_mount_onfail) { 812 case A_CONTINUE: 813 break; 814 case A_PANIC: 815 panic("mountroot: unable to (re-)mount root."); 816 /* NOTREACHED */ 817 case A_RETRY: 818 goto retry; 819 case A_REBOOT: 820 kern_reboot(RB_NOSYNC); 821 /* NOTREACHED */ 822 } 823 824 return (error); 825} 826 827static void 828vfs_mountroot_conf0(struct sbuf *sb) 829{ 830 char *s, *tok, *mnt, *opt; 831 int error; 832 833 sbuf_printf(sb, ".onfail panic\n"); 834 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 835 if (boothowto & RB_ASKNAME) 836 sbuf_printf(sb, ".ask\n"); 837#ifdef ROOTDEVNAME 838 if (boothowto & RB_DFLTROOT) 839 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 840#endif 841 if (boothowto & RB_CDROM) { 842 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n"); 843 sbuf_printf(sb, ".timeout 0\n"); 844 sbuf_printf(sb, "cd9660:/dev/acd0 ro\n"); 845 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout); 846 } 847 s = kern_getenv("vfs.root.mountfrom"); 848 if (s != NULL) { 849 opt = kern_getenv("vfs.root.mountfrom.options"); 850 tok = s; 851 error = parse_token(&tok, &mnt); 852 while (!error) { 853 sbuf_printf(sb, "%s %s\n", mnt, 854 (opt != NULL) ? opt : ""); 855 free(mnt, M_TEMP); 856 error = parse_token(&tok, &mnt); 857 } 858 if (opt != NULL) 859 freeenv(opt); 860 freeenv(s); 861 } 862 if (rootdevnames[0] != NULL) 863 sbuf_printf(sb, "%s\n", rootdevnames[0]); 864 if (rootdevnames[1] != NULL) 865 sbuf_printf(sb, "%s\n", rootdevnames[1]); 866#ifdef ROOTDEVNAME 867 if (!(boothowto & RB_DFLTROOT)) 868 sbuf_printf(sb, "%s\n", ROOTDEVNAME); 869#endif 870 if (!(boothowto & RB_ASKNAME)) 871 sbuf_printf(sb, ".ask\n"); 872} 873 874static int 875vfs_mountroot_readconf(struct thread *td, struct sbuf *sb) 876{ 877 static char buf[128]; 878 struct nameidata nd; 879 off_t ofs; 880 ssize_t resid; 881 int error, flags, len; 882 883 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td); 884 flags = FREAD; 885 error = vn_open(&nd, &flags, 0, NULL); 886 if (error) 887 return (error); 888 889 NDFREE(&nd, NDF_ONLY_PNBUF); 890 ofs = 0; 891 len = sizeof(buf) - 1; 892 while (1) { 893 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs, 894 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 895 NOCRED, &resid, td); 896 if (error) 897 break; 898 if (resid == len) 899 break; 900 buf[len - resid] = 0; 901 sbuf_printf(sb, "%s", buf); 902 ofs += len - resid; 903 } 904 905 VOP_UNLOCK(nd.ni_vp, 0); 906 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 907 return (error); 908} 909 910static void 911vfs_mountroot_wait(void) 912{ 913 struct root_hold_token *h; 914 struct timeval lastfail; 915 int curfail; 916 917 curfail = 0; 918 while (1) { 919 DROP_GIANT(); 920 g_waitidle(); 921 PICKUP_GIANT(); 922 mtx_lock(&root_holds_mtx); 923 if (LIST_EMPTY(&root_holds)) { 924 mtx_unlock(&root_holds_mtx); 925 break; 926 } 927 if (ppsratecheck(&lastfail, &curfail, 1)) { 928 printf("Root mount waiting for:"); 929 LIST_FOREACH(h, &root_holds, list) 930 printf(" %s", h->who); 931 printf("\n"); 932 } 933 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold", 934 hz); 935 } 936} 937 938void 939vfs_mountroot(void) 940{ 941 struct mount *mp; 942 struct sbuf *sb; 943 struct thread *td; 944 time_t timebase; 945 int error; 946 947 td = curthread; 948 949 vfs_mountroot_wait(); 950 951 sb = sbuf_new_auto(); 952 vfs_mountroot_conf0(sb); 953 sbuf_finish(sb); 954 955 error = vfs_mountroot_devfs(td, &mp); 956 while (!error) { 957 error = vfs_mountroot_parse(sb, mp); 958 if (!error) { 959 error = vfs_mountroot_shuffle(td, mp); 960 if (!error) { 961 sbuf_clear(sb); 962 error = vfs_mountroot_readconf(td, sb); 963 sbuf_finish(sb); 964 } 965 } 966 } 967 968 sbuf_delete(sb); 969 970 /* 971 * Iterate over all currently mounted file systems and use 972 * the time stamp found to check and/or initialize the RTC. 973 * Call inittodr() only once and pass it the largest of the 974 * timestamps we encounter. 975 */ 976 timebase = 0; 977 mtx_lock(&mountlist_mtx); 978 mp = TAILQ_FIRST(&mountlist); 979 while (mp != NULL) { 980 if (mp->mnt_time > timebase) 981 timebase = mp->mnt_time; 982 mp = TAILQ_NEXT(mp, mnt_list); 983 } 984 mtx_unlock(&mountlist_mtx); 985 inittodr(timebase); 986 987 /* Keep prison0's root in sync with the global rootvnode. */ 988 mtx_lock(&prison0.pr_mtx); 989 prison0.pr_root = rootvnode; 990 vref(prison0.pr_root); 991 mtx_unlock(&prison0.pr_mtx); 992 993 mtx_lock(&root_holds_mtx); 994 atomic_store_rel_int(&root_mount_complete, 1); 995 wakeup(&root_mount_complete); 996 mtx_unlock(&root_holds_mtx); 997 998 EVENTHANDLER_INVOKE(mountroot); 999} 1000 1001static struct mntarg * 1002parse_mountroot_options(struct mntarg *ma, const char *options) 1003{ 1004 char *p; 1005 char *name, *name_arg; 1006 char *val, *val_arg; 1007 char *opts; 1008 1009 if (options == NULL || options[0] == '\0') 1010 return (ma); 1011 1012 p = opts = strdup(options, M_MOUNT); 1013 if (opts == NULL) { 1014 return (ma); 1015 } 1016 1017 while((name = strsep(&p, ",")) != NULL) { 1018 if (name[0] == '\0') 1019 break; 1020 1021 val = strchr(name, '='); 1022 if (val != NULL) { 1023 *val = '\0'; 1024 ++val; 1025 } 1026 if( strcmp(name, "rw") == 0 || 1027 strcmp(name, "noro") == 0) { 1028 /* 1029 * The first time we mount the root file system, 1030 * we need to mount 'ro', so We need to ignore 1031 * 'rw' and 'noro' mount options. 1032 */ 1033 continue; 1034 } 1035 name_arg = strdup(name, M_MOUNT); 1036 val_arg = NULL; 1037 if (val != NULL) 1038 val_arg = strdup(val, M_MOUNT); 1039 1040 ma = mount_arg(ma, name_arg, val_arg, 1041 (val_arg != NULL ? -1 : 0)); 1042 } 1043 free(opts, M_MOUNT); 1044 return (ma); 1045} 1046