vfs_mount.c revision 157322
1/*- 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1999 Michael Smith 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD: head/sys/kern/vfs_mount.c 157322 2006-03-31 03:49:51Z jeff $"); 39 40#include <sys/param.h> 41#include <sys/conf.h> 42#include <sys/jail.h> 43#include <sys/kernel.h> 44#include <sys/libkern.h> 45#include <sys/mac.h> 46#include <sys/malloc.h> 47#include <sys/mount.h> 48#include <sys/mutex.h> 49#include <sys/namei.h> 50#include <sys/proc.h> 51#include <sys/filedesc.h> 52#include <sys/reboot.h> 53#include <sys/syscallsubr.h> 54#include <sys/sysproto.h> 55#include <sys/sx.h> 56#include <sys/sysctl.h> 57#include <sys/sysent.h> 58#include <sys/systm.h> 59#include <sys/vnode.h> 60#include <vm/uma.h> 61 62#include <geom/geom.h> 63 64#include <machine/stdarg.h> 65 66#include "opt_rootdevname.h" 67#include "opt_ddb.h" 68#include "opt_mac.h" 69 70#ifdef DDB 71#include <ddb/ddb.h> 72#endif 73 74#define ROOTNAME "root_device" 75#define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 76 77static int vfs_domount(struct thread *td, const char *fstype, 78 char *fspath, int fsflags, void *fsdata); 79static struct mount *vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 80 const char *fspath, struct thread *td); 81static int vfs_mountroot_ask(void); 82static int vfs_mountroot_try(const char *mountfrom); 83static int vfs_donmount(struct thread *td, int fsflags, 84 struct uio *fsoptions); 85static void free_mntarg(struct mntarg *ma); 86static void vfs_mount_destroy(struct mount *, struct thread *); 87static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 88 89static int usermount = 0; 90SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 91 "Unprivileged users may mount and unmount file systems"); 92 93MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 94MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 95static uma_zone_t mount_zone; 96 97/* List of mounted filesystems. */ 98struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 99 100/* For any iteration/modification of mountlist */ 101struct mtx mountlist_mtx; 102MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 103 104TAILQ_HEAD(vfsoptlist, vfsopt); 105struct vfsopt { 106 TAILQ_ENTRY(vfsopt) link; 107 char *name; 108 void *value; 109 int len; 110}; 111 112/* 113 * The vnode of the system's root (/ in the filesystem, without chroot 114 * active.) 115 */ 116struct vnode *rootvnode; 117 118/* 119 * The root filesystem is detailed in the kernel environment variable 120 * vfs.root.mountfrom, which is expected to be in the general format 121 * 122 * <vfsname>:[<path>] 123 * vfsname := the name of a VFS known to the kernel and capable 124 * of being mounted as root 125 * path := disk device name or other data used by the filesystem 126 * to locate its physical store 127 */ 128 129/* 130 * Global opts, taken by all filesystems 131 */ 132static const char *global_opts[] = { 133 "errmsg", 134 "fstype", 135 "fspath", 136 "rdonly", 137 "ro", 138 "rw", 139 "suid", 140 "exec", 141 NULL 142}; 143 144/* 145 * The root specifiers we will try if RB_CDROM is specified. 146 */ 147static char *cdrom_rootdevnames[] = { 148 "cd9660:cd0", 149 "cd9660:acd0", 150 NULL 151}; 152 153/* legacy find-root code */ 154char *rootdevnames[2] = {NULL, NULL}; 155#ifndef ROOTDEVNAME 156# define ROOTDEVNAME NULL 157#endif 158static const char *ctrootdevname = ROOTDEVNAME; 159 160/* 161 * --------------------------------------------------------------------- 162 * Functions for building and sanitizing the mount options 163 */ 164 165/* Remove one mount option. */ 166static void 167vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 168{ 169 170 TAILQ_REMOVE(opts, opt, link); 171 free(opt->name, M_MOUNT); 172 if (opt->value != NULL) 173 free(opt->value, M_MOUNT); 174#ifdef INVARIANTS 175 else if (opt->len != 0) 176 panic("%s: mount option with NULL value but length != 0", 177 __func__); 178#endif 179 free(opt, M_MOUNT); 180} 181 182/* Release all resources related to the mount options. */ 183static void 184vfs_freeopts(struct vfsoptlist *opts) 185{ 186 struct vfsopt *opt; 187 188 while (!TAILQ_EMPTY(opts)) { 189 opt = TAILQ_FIRST(opts); 190 vfs_freeopt(opts, opt); 191 } 192 free(opts, M_MOUNT); 193} 194 195/* 196 * Check if options are equal (with or without the "no" prefix). 197 */ 198static int 199vfs_equalopts(const char *opt1, const char *opt2) 200{ 201 202 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 203 if (strcmp(opt1, opt2) == 0) 204 return (1); 205 /* "noopt" vs. "opt" */ 206 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 207 return (1); 208 /* "opt" vs. "noopt" */ 209 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 210 return (1); 211 return (0); 212} 213 214/* 215 * If a mount option is specified several times, 216 * (with or without the "no" prefix) only keep 217 * the last occurence of it. 218 */ 219static void 220vfs_sanitizeopts(struct vfsoptlist *opts) 221{ 222 struct vfsopt *opt, *opt2, *tmp; 223 224 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 225 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 226 while (opt2 != NULL) { 227 if (vfs_equalopts(opt->name, opt2->name)) { 228 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 229 vfs_freeopt(opts, opt2); 230 opt2 = tmp; 231 } else { 232 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 233 } 234 } 235 } 236} 237 238/* 239 * Build a linked list of mount options from a struct uio. 240 */ 241static int 242vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 243{ 244 struct vfsoptlist *opts; 245 struct vfsopt *opt; 246 size_t memused; 247 unsigned int i, iovcnt; 248 int error, namelen, optlen; 249 250 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 251 TAILQ_INIT(opts); 252 memused = 0; 253 iovcnt = auio->uio_iovcnt; 254 for (i = 0; i < iovcnt; i += 2) { 255 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 256 namelen = auio->uio_iov[i].iov_len; 257 optlen = auio->uio_iov[i + 1].iov_len; 258 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 259 opt->value = NULL; 260 opt->len = 0; 261 262 /* 263 * Do this early, so jumps to "bad" will free the current 264 * option. 265 */ 266 TAILQ_INSERT_TAIL(opts, opt, link); 267 memused += sizeof(struct vfsopt) + optlen + namelen; 268 269 /* 270 * Avoid consuming too much memory, and attempts to overflow 271 * memused. 272 */ 273 if (memused > VFS_MOUNTARG_SIZE_MAX || 274 optlen > VFS_MOUNTARG_SIZE_MAX || 275 namelen > VFS_MOUNTARG_SIZE_MAX) { 276 error = EINVAL; 277 goto bad; 278 } 279 280 if (auio->uio_segflg == UIO_SYSSPACE) { 281 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 282 } else { 283 error = copyin(auio->uio_iov[i].iov_base, opt->name, 284 namelen); 285 if (error) 286 goto bad; 287 } 288 /* Ensure names are null-terminated strings. */ 289 if (opt->name[namelen - 1] != '\0') { 290 error = EINVAL; 291 goto bad; 292 } 293 if (optlen != 0) { 294 opt->len = optlen; 295 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 296 if (auio->uio_segflg == UIO_SYSSPACE) { 297 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 298 optlen); 299 } else { 300 error = copyin(auio->uio_iov[i + 1].iov_base, 301 opt->value, optlen); 302 if (error) 303 goto bad; 304 } 305 } 306 } 307 vfs_sanitizeopts(opts); 308 *options = opts; 309 return (0); 310bad: 311 vfs_freeopts(opts); 312 return (error); 313} 314 315/* 316 * Merge the old mount options with the new ones passed 317 * in the MNT_UPDATE case. 318 */ 319static void 320vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 321{ 322 struct vfsopt *opt, *opt2, *new; 323 324 TAILQ_FOREACH(opt, opts, link) { 325 /* 326 * Check that this option hasn't been redefined 327 * nor cancelled with a "no" mount option. 328 */ 329 opt2 = TAILQ_FIRST(toopts); 330 while (opt2 != NULL) { 331 if (strcmp(opt2->name, opt->name) == 0) 332 goto next; 333 if (strncmp(opt2->name, "no", 2) == 0 && 334 strcmp(opt2->name + 2, opt->name) == 0) { 335 vfs_freeopt(toopts, opt2); 336 goto next; 337 } 338 opt2 = TAILQ_NEXT(opt2, link); 339 } 340 /* We want this option, duplicate it. */ 341 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 342 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 343 strcpy(new->name, opt->name); 344 if (opt->len != 0) { 345 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 346 bcopy(opt->value, new->value, opt->len); 347 } else { 348 new->value = NULL; 349 } 350 new->len = opt->len; 351 TAILQ_INSERT_TAIL(toopts, new, link); 352next: 353 continue; 354 } 355} 356 357/* 358 * --------------------------------------------------------------------- 359 * Mount a filesystem 360 */ 361int 362nmount(td, uap) 363 struct thread *td; 364 struct nmount_args /* { 365 struct iovec *iovp; 366 unsigned int iovcnt; 367 int flags; 368 } */ *uap; 369{ 370 struct uio *auio; 371 struct iovec *iov; 372 unsigned int i; 373 int error; 374 u_int iovcnt; 375 376 /* Kick out MNT_ROOTFS early as it is legal internally */ 377 if (uap->flags & MNT_ROOTFS) 378 return (EINVAL); 379 380 iovcnt = uap->iovcnt; 381 /* 382 * Check that we have an even number of iovec's 383 * and that we have at least two options. 384 */ 385 if ((iovcnt & 1) || (iovcnt < 4)) 386 return (EINVAL); 387 388 error = copyinuio(uap->iovp, iovcnt, &auio); 389 if (error) 390 return (error); 391 iov = auio->uio_iov; 392 for (i = 0; i < iovcnt; i++) { 393 if (iov->iov_len > MMAXOPTIONLEN) { 394 free(auio, M_IOV); 395 return (EINVAL); 396 } 397 iov++; 398 } 399 error = vfs_donmount(td, uap->flags, auio); 400 401 free(auio, M_IOV); 402 return (error); 403} 404 405/* 406 * --------------------------------------------------------------------- 407 * Various utility functions 408 */ 409 410void 411vfs_ref(struct mount *mp) 412{ 413 414 MNT_ILOCK(mp); 415 MNT_REF(mp); 416 MNT_IUNLOCK(mp); 417} 418 419void 420vfs_rel(struct mount *mp) 421{ 422 423 MNT_ILOCK(mp); 424 MNT_REL(mp); 425 MNT_IUNLOCK(mp); 426} 427 428static int 429mount_init(void *mem, int size, int flags) 430{ 431 struct mount *mp; 432 433 mp = (struct mount *)mem; 434 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 435 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0); 436 return (0); 437} 438 439static void 440mount_fini(void *mem, int size) 441{ 442 struct mount *mp; 443 444 mp = (struct mount *)mem; 445 lockdestroy(&mp->mnt_lock); 446 mtx_destroy(&mp->mnt_mtx); 447} 448 449/* 450 * Allocate and initialize the mount point struct. 451 */ 452static struct mount * 453vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 454 const char *fspath, struct thread *td) 455{ 456 struct mount *mp; 457 458 mp = uma_zalloc(mount_zone, M_WAITOK); 459 bzero(&mp->mnt_startzero, 460 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 461 TAILQ_INIT(&mp->mnt_nvnodelist); 462 mp->mnt_nvnodelistsize = 0; 463 mp->mnt_ref = 0; 464 (void) vfs_busy(mp, LK_NOWAIT, 0, td); 465 mp->mnt_op = vfsp->vfc_vfsops; 466 mp->mnt_vfc = vfsp; 467 vfsp->vfc_refcount++; /* XXX Unlocked */ 468 mp->mnt_stat.f_type = vfsp->vfc_typenum; 469 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 470 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 471 mp->mnt_vnodecovered = vp; 472 mp->mnt_cred = crdup(td->td_ucred); 473 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 474 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 475 mp->mnt_iosize_max = DFLTPHYS; 476#ifdef MAC 477 mac_init_mount(mp); 478 mac_create_mount(td->td_ucred, mp); 479#endif 480 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 481 return (mp); 482} 483 484/* 485 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 486 */ 487static void 488vfs_mount_destroy(struct mount *mp, struct thread *td) 489{ 490 int i; 491 492 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 493 MNT_ILOCK(mp); 494 for (i = 0; mp->mnt_ref && i < 3; i++) 495 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 496 /* 497 * This will always cause a 3 second delay in rebooting due to 498 * refs on the root mountpoint that never go away. Most of these 499 * are held by init which never exits. 500 */ 501 if (i == 3 && (!rebooting || bootverbose)) 502 printf("Mount point %s had %d dangling refs\n", 503 mp->mnt_stat.f_mntonname, mp->mnt_ref); 504 if (mp->mnt_holdcnt != 0) { 505 printf("Waiting for mount point to be unheld\n"); 506 while (mp->mnt_holdcnt != 0) { 507 mp->mnt_holdcntwaiters++; 508 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 509 PZERO, "mntdestroy", 0); 510 mp->mnt_holdcntwaiters--; 511 } 512 printf("mount point unheld\n"); 513 } 514 if (mp->mnt_writeopcount > 0) { 515 printf("Waiting for mount point write ops\n"); 516 while (mp->mnt_writeopcount > 0) { 517 mp->mnt_kern_flag |= MNTK_SUSPEND; 518 msleep(&mp->mnt_writeopcount, 519 MNT_MTX(mp), 520 PZERO, "mntdestroy2", 0); 521 } 522 printf("mount point write ops completed\n"); 523 } 524 if (mp->mnt_secondary_writes > 0) { 525 printf("Waiting for mount point secondary write ops\n"); 526 while (mp->mnt_secondary_writes > 0) { 527 mp->mnt_kern_flag |= MNTK_SUSPEND; 528 msleep(&mp->mnt_secondary_writes, 529 MNT_MTX(mp), 530 PZERO, "mntdestroy3", 0); 531 } 532 printf("mount point secondary write ops completed\n"); 533 } 534 MNT_IUNLOCK(mp); 535 mp->mnt_vfc->vfc_refcount--; 536 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 537 panic("unmount: dangling vnode"); 538 MNT_ILOCK(mp); 539 if (mp->mnt_kern_flag & MNTK_MWAIT) 540 wakeup(mp); 541 if (mp->mnt_writeopcount != 0) 542 panic("vfs_mount_destroy: nonzero writeopcount"); 543 if (mp->mnt_secondary_writes != 0) 544 panic("vfs_mount_destroy: nonzero secondary_writes"); 545 if (mp->mnt_nvnodelistsize != 0) 546 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 547 mp->mnt_writeopcount = -1000; 548 mp->mnt_nvnodelistsize = -1000; 549 mp->mnt_secondary_writes = -1000; 550 MNT_IUNLOCK(mp); 551#ifdef MAC 552 mac_destroy_mount(mp); 553#endif 554 if (mp->mnt_opt != NULL) 555 vfs_freeopts(mp->mnt_opt); 556 crfree(mp->mnt_cred); 557 uma_zfree(mount_zone, mp); 558} 559 560static int 561vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 562{ 563 struct vfsoptlist *optlist; 564 struct vfsopt *opt; 565 char *fstype, *fspath, *errmsg; 566 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 567 568 errmsg_len = 0; 569 errmsg_pos = -1; 570 571 error = vfs_buildopts(fsoptions, &optlist); 572 if (error) 573 return (error); 574 575 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 576 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 577 else 578 errmsg_len = 0; 579 580 /* 581 * We need these two options before the others, 582 * and they are mandatory for any filesystem. 583 * Ensure they are NUL terminated as well. 584 */ 585 fstypelen = 0; 586 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 587 if (error || fstype[fstypelen - 1] != '\0') { 588 error = EINVAL; 589 if (errmsg != NULL) 590 strncpy(errmsg, "Invalid fstype", errmsg_len); 591 goto bail; 592 } 593 fspathlen = 0; 594 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 595 if (error || fspath[fspathlen - 1] != '\0') { 596 error = EINVAL; 597 if (errmsg != NULL) 598 strncpy(errmsg, "Invalid fspath", errmsg_len); 599 goto bail; 600 } 601 602 /* 603 * We need to see if we have the "update" option 604 * before we call vfs_domount(), since vfs_domount() has special 605 * logic based on MNT_UPDATE. This is very important 606 * when we want to update the root filesystem. 607 */ 608 TAILQ_FOREACH(opt, optlist, link) { 609 if (strcmp(opt->name, "update") == 0) 610 fsflags |= MNT_UPDATE; 611 else if (strcmp(opt->name, "async") == 0) 612 fsflags |= MNT_ASYNC; 613 else if (strcmp(opt->name, "force") == 0) 614 fsflags |= MNT_FORCE; 615 else if (strcmp(opt->name, "multilabel") == 0) 616 fsflags |= MNT_MULTILABEL; 617 else if (strcmp(opt->name, "noasync") == 0) 618 fsflags &= ~MNT_ASYNC; 619 else if (strcmp(opt->name, "noatime") == 0) 620 fsflags |= MNT_NOATIME; 621 else if (strcmp(opt->name, "noclusterr") == 0) 622 fsflags |= MNT_NOCLUSTERR; 623 else if (strcmp(opt->name, "noclusterw") == 0) 624 fsflags |= MNT_NOCLUSTERW; 625 else if (strcmp(opt->name, "noexec") == 0) 626 fsflags |= MNT_NOEXEC; 627 else if (strcmp(opt->name, "nosuid") == 0) 628 fsflags |= MNT_NOSUID; 629 else if (strcmp(opt->name, "nosymfollow") == 0) 630 fsflags |= MNT_NOSYMFOLLOW; 631 else if (strcmp(opt->name, "noro") == 0 || 632 strcmp(opt->name, "rw") == 0) 633 fsflags &= ~MNT_RDONLY; 634 else if (strcmp(opt->name, "ro") == 0 || 635 strcmp(opt->name, "rdonly") == 0) 636 fsflags |= MNT_RDONLY; 637 else if (strcmp(opt->name, "snapshot") == 0) 638 fsflags |= MNT_SNAPSHOT; 639 else if (strcmp(opt->name, "suiddir") == 0) 640 fsflags |= MNT_SUIDDIR; 641 else if (strcmp(opt->name, "sync") == 0) 642 fsflags |= MNT_SYNCHRONOUS; 643 else if (strcmp(opt->name, "union") == 0) 644 fsflags |= MNT_UNION; 645 } 646 647 /* 648 * Be ultra-paranoid about making sure the type and fspath 649 * variables will fit in our mp buffers, including the 650 * terminating NUL. 651 */ 652 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 653 error = ENAMETOOLONG; 654 goto bail; 655 } 656 657 mtx_lock(&Giant); 658 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 659 mtx_unlock(&Giant); 660bail: 661 /* copyout the errmsg */ 662 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 663 && errmsg_len > 0 && errmsg != NULL) { 664 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 665 strncpy(fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 666 errmsg, 667 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 668 } else { 669 copystr(errmsg, 670 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 671 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len, 672 NULL); 673 } 674 } 675 676 if (error != 0) 677 vfs_freeopts(optlist); 678 return (error); 679} 680 681/* 682 * --------------------------------------------------------------------- 683 * Old mount API. 684 */ 685#ifndef _SYS_SYSPROTO_H_ 686struct mount_args { 687 char *type; 688 char *path; 689 int flags; 690 caddr_t data; 691}; 692#endif 693/* ARGSUSED */ 694int 695mount(td, uap) 696 struct thread *td; 697 struct mount_args /* { 698 char *type; 699 char *path; 700 int flags; 701 caddr_t data; 702 } */ *uap; 703{ 704 char *fstype; 705 struct vfsconf *vfsp = NULL; 706 struct mntarg *ma = NULL; 707 int error; 708 709 /* Kick out MNT_ROOTFS early as it is legal internally */ 710 uap->flags &= ~MNT_ROOTFS; 711 712 if (uap->data == NULL) 713 return (EINVAL); 714 715 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 716 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 717 if (!error) { 718 mtx_lock(&Giant); /* XXX ? */ 719 vfsp = vfs_byname_kld(fstype, td, &error); 720 mtx_unlock(&Giant); 721 } 722 free(fstype, M_TEMP); 723 if (error) 724 return (error); 725 if (vfsp == NULL) 726 return (ENOENT); 727 if (vfsp->vfc_vfsops->vfs_cmount == NULL) 728 return (EOPNOTSUPP); 729 730 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 731 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 732 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 733 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 734 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 735 736 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 737 return (error); 738} 739 740 741/* 742 * vfs_domount(): actually attempt a filesystem mount. 743 */ 744static int 745vfs_domount( 746 struct thread *td, /* Flags common to all filesystems. */ 747 const char *fstype, /* Filesystem type. */ 748 char *fspath, /* Mount path. */ 749 int fsflags, /* Flags common to all filesystems. */ 750 void *fsdata /* Options local to the filesystem. */ 751 ) 752{ 753 struct vnode *vp; 754 struct mount *mp; 755 struct vfsconf *vfsp; 756 int error, flag = 0, kern_flag = 0; 757 struct vattr va; 758 struct nameidata nd; 759 760 mtx_assert(&Giant, MA_OWNED); 761 /* 762 * Be ultra-paranoid about making sure the type and fspath 763 * variables will fit in our mp buffers, including the 764 * terminating NUL. 765 */ 766 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 767 return (ENAMETOOLONG); 768 769 if (jailed(td->td_ucred)) 770 return (EPERM); 771 if (usermount == 0) { 772 if ((error = suser(td)) != 0) 773 return (error); 774 } 775 776 /* 777 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 778 */ 779 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 780 if ((error = suser(td)) != 0) 781 return (error); 782 } 783 /* 784 * Silently enforce MNT_NOSUID and MNT_USER for 785 * unprivileged users. 786 */ 787 if (suser(td) != 0) 788 fsflags |= MNT_NOSUID | MNT_USER; 789 790 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 791 vfsp = NULL; 792 if ((fsflags & MNT_UPDATE) == 0) { 793 /* Don't try to load KLDs if we're mounting the root. */ 794 if (fsflags & MNT_ROOTFS) 795 vfsp = vfs_byname(fstype); 796 else 797 vfsp = vfs_byname_kld(fstype, td, &error); 798 if (vfsp == NULL) 799 return (ENODEV); 800 } 801 /* 802 * Get vnode to be covered 803 */ 804 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 805 if ((error = namei(&nd)) != 0) 806 return (error); 807 NDFREE(&nd, NDF_ONLY_PNBUF); 808 vp = nd.ni_vp; 809 if (fsflags & MNT_UPDATE) { 810 if ((vp->v_vflag & VV_ROOT) == 0) { 811 vput(vp); 812 return (EINVAL); 813 } 814 mp = vp->v_mount; 815 flag = mp->mnt_flag; 816 kern_flag = mp->mnt_kern_flag; 817 /* 818 * We only allow the filesystem to be reloaded if it 819 * is currently mounted read-only. 820 */ 821 if ((fsflags & MNT_RELOAD) && 822 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 823 vput(vp); 824 return (EOPNOTSUPP); /* Needs translation */ 825 } 826 /* 827 * Only privileged root, or (if MNT_USER is set) the user that 828 * did the original mount is permitted to update it. 829 */ 830 error = vfs_suser(mp, td); 831 if (error) { 832 vput(vp); 833 return (error); 834 } 835 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 836 vput(vp); 837 return (EBUSY); 838 } 839 VI_LOCK(vp); 840 if ((vp->v_iflag & VI_MOUNT) != 0 || 841 vp->v_mountedhere != NULL) { 842 VI_UNLOCK(vp); 843 vfs_unbusy(mp, td); 844 vput(vp); 845 return (EBUSY); 846 } 847 vp->v_iflag |= VI_MOUNT; 848 VI_UNLOCK(vp); 849 mp->mnt_flag |= fsflags & 850 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 851 VOP_UNLOCK(vp, 0, td); 852 mp->mnt_optnew = fsdata; 853 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 854 } else { 855 /* 856 * If the user is not root, ensure that they own the directory 857 * onto which we are attempting to mount. 858 */ 859 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 860 if (error) { 861 vput(vp); 862 return (error); 863 } 864 if (va.va_uid != td->td_ucred->cr_uid) { 865 if ((error = suser(td)) != 0) { 866 vput(vp); 867 return (error); 868 } 869 } 870 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 871 if (error != 0) { 872 vput(vp); 873 return (error); 874 } 875 if (vp->v_type != VDIR) { 876 vput(vp); 877 return (ENOTDIR); 878 } 879 VI_LOCK(vp); 880 if ((vp->v_iflag & VI_MOUNT) != 0 || 881 vp->v_mountedhere != NULL) { 882 VI_UNLOCK(vp); 883 vput(vp); 884 return (EBUSY); 885 } 886 vp->v_iflag |= VI_MOUNT; 887 VI_UNLOCK(vp); 888 889 /* 890 * Allocate and initialize the filesystem. 891 */ 892 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 893 VOP_UNLOCK(vp, 0, td); 894 895 /* XXXMAC: pass to vfs_mount_alloc? */ 896 mp->mnt_optnew = fsdata; 897 } 898 899 /* 900 * Set the mount level flags. 901 */ 902 if (fsflags & MNT_RDONLY) 903 mp->mnt_flag |= MNT_RDONLY; 904 mp->mnt_flag &=~ MNT_UPDATEMASK; 905 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS); 906 /* 907 * Mount the filesystem. 908 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 909 * get. No freeing of cn_pnbuf. 910 */ 911 error = VFS_MOUNT(mp, td); 912 if (!error) { 913 if (mp->mnt_opt != NULL) 914 vfs_freeopts(mp->mnt_opt); 915 mp->mnt_opt = mp->mnt_optnew; 916 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 917 } 918 /* 919 * Prevent external consumers of mount options from reading 920 * mnt_optnew. 921 */ 922 mp->mnt_optnew = NULL; 923 if (mp->mnt_flag & MNT_UPDATE) { 924 mp->mnt_flag &= 925 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 926 if (error) { 927 mp->mnt_flag = flag; 928 mp->mnt_kern_flag = kern_flag; 929 } 930 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 931 if (mp->mnt_syncer == NULL) 932 error = vfs_allocate_syncvnode(mp); 933 } else { 934 if (mp->mnt_syncer != NULL) 935 vrele(mp->mnt_syncer); 936 mp->mnt_syncer = NULL; 937 } 938 vfs_unbusy(mp, td); 939 VI_LOCK(vp); 940 vp->v_iflag &= ~VI_MOUNT; 941 VI_UNLOCK(vp); 942 vrele(vp); 943 return (error); 944 } 945 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 946 /* 947 * Put the new filesystem on the mount list after root. 948 */ 949 cache_purge(vp); 950 if (!error) { 951 struct vnode *newdp; 952 953 VI_LOCK(vp); 954 vp->v_iflag &= ~VI_MOUNT; 955 VI_UNLOCK(vp); 956 vp->v_mountedhere = mp; 957 mtx_lock(&mountlist_mtx); 958 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 959 mtx_unlock(&mountlist_mtx); 960 vfs_event_signal(NULL, VQ_MOUNT, 0); 961 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 962 panic("mount: lost mount"); 963 mountcheckdirs(vp, newdp); 964 vput(newdp); 965 VOP_UNLOCK(vp, 0, td); 966 if ((mp->mnt_flag & MNT_RDONLY) == 0) 967 error = vfs_allocate_syncvnode(mp); 968 vfs_unbusy(mp, td); 969 if (error) 970 vrele(vp); 971 } else { 972 VI_LOCK(vp); 973 vp->v_iflag &= ~VI_MOUNT; 974 VI_UNLOCK(vp); 975 vfs_mount_destroy(mp, td); 976 vput(vp); 977 } 978 return (error); 979} 980 981/* 982 * --------------------------------------------------------------------- 983 * Unmount a filesystem. 984 * 985 * Note: unmount takes a path to the vnode mounted on as argument, 986 * not special file (as before). 987 */ 988#ifndef _SYS_SYSPROTO_H_ 989struct unmount_args { 990 char *path; 991 int flags; 992}; 993#endif 994/* ARGSUSED */ 995int 996unmount(td, uap) 997 struct thread *td; 998 register struct unmount_args /* { 999 char *path; 1000 int flags; 1001 } */ *uap; 1002{ 1003 struct mount *mp; 1004 char *pathbuf; 1005 int error, id0, id1; 1006 1007 if (jailed(td->td_ucred)) 1008 return (EPERM); 1009 if (usermount == 0) { 1010 if ((error = suser(td)) != 0) 1011 return (error); 1012 } 1013 1014 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1015 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1016 if (error) { 1017 free(pathbuf, M_TEMP); 1018 return (error); 1019 } 1020 if (uap->flags & MNT_BYFSID) { 1021 /* Decode the filesystem ID. */ 1022 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1023 free(pathbuf, M_TEMP); 1024 return (EINVAL); 1025 } 1026 1027 mtx_lock(&mountlist_mtx); 1028 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1029 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1030 mp->mnt_stat.f_fsid.val[1] == id1) 1031 break; 1032 } 1033 mtx_unlock(&mountlist_mtx); 1034 } else { 1035 mtx_lock(&mountlist_mtx); 1036 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1037 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1038 break; 1039 } 1040 mtx_unlock(&mountlist_mtx); 1041 } 1042 free(pathbuf, M_TEMP); 1043 if (mp == NULL) { 1044 /* 1045 * Previously we returned ENOENT for a nonexistent path and 1046 * EINVAL for a non-mountpoint. We cannot tell these apart 1047 * now, so in the !MNT_BYFSID case return the more likely 1048 * EINVAL for compatibility. 1049 */ 1050 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1051 } 1052 1053 /* 1054 * Only privileged root, or (if MNT_USER is set) the user that did the 1055 * original mount is permitted to unmount this filesystem. 1056 */ 1057 error = vfs_suser(mp, td); 1058 if (error) 1059 return (error); 1060 1061 /* 1062 * Don't allow unmounting the root filesystem. 1063 */ 1064 if (mp->mnt_flag & MNT_ROOTFS) 1065 return (EINVAL); 1066 mtx_lock(&Giant); 1067 error = dounmount(mp, uap->flags, td); 1068 mtx_unlock(&Giant); 1069 return (error); 1070} 1071 1072/* 1073 * Do the actual filesystem unmount. 1074 */ 1075int 1076dounmount(mp, flags, td) 1077 struct mount *mp; 1078 int flags; 1079 struct thread *td; 1080{ 1081 struct vnode *coveredvp, *fsrootvp; 1082 int error; 1083 int async_flag; 1084 1085 mtx_assert(&Giant, MA_OWNED); 1086 1087 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 1088 vn_lock(coveredvp, LK_EXCLUSIVE | LK_RETRY, td); 1089 MNT_ILOCK(mp); 1090 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1091 MNT_IUNLOCK(mp); 1092 if (coveredvp) 1093 VOP_UNLOCK(coveredvp, 0, td); 1094 return (EBUSY); 1095 } 1096 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1097 /* Allow filesystems to detect that a forced unmount is in progress. */ 1098 if (flags & MNT_FORCE) 1099 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1100 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1101 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1102 if (error) { 1103 MNT_ILOCK(mp); 1104 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1105 if (mp->mnt_kern_flag & MNTK_MWAIT) 1106 wakeup(mp); 1107 MNT_IUNLOCK(mp); 1108 if (coveredvp) 1109 VOP_UNLOCK(coveredvp, 0, td); 1110 return (error); 1111 } 1112 vn_start_write(NULL, &mp, V_WAIT); 1113 1114 if (mp->mnt_flag & MNT_EXPUBLIC) 1115 vfs_setpublicfs(NULL, NULL, NULL); 1116 1117 vfs_msync(mp, MNT_WAIT); 1118 async_flag = mp->mnt_flag & MNT_ASYNC; 1119 mp->mnt_flag &= ~MNT_ASYNC; 1120 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1121 if (mp->mnt_syncer != NULL) 1122 vrele(mp->mnt_syncer); 1123 /* 1124 * For forced unmounts, move process cdir/rdir refs on the fs root 1125 * vnode to the covered vnode. For non-forced unmounts we want 1126 * such references to cause an EBUSY error. 1127 */ 1128 if ((flags & MNT_FORCE) && 1129 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1130 if (mp->mnt_vnodecovered != NULL) 1131 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1132 if (fsrootvp == rootvnode) { 1133 vrele(rootvnode); 1134 rootvnode = NULL; 1135 } 1136 vput(fsrootvp); 1137 } 1138 if (((mp->mnt_flag & MNT_RDONLY) || 1139 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1140 (flags & MNT_FORCE)) { 1141 error = VFS_UNMOUNT(mp, flags, td); 1142 } 1143 vn_finished_write(mp); 1144 if (error) { 1145 /* Undo cdir/rdir and rootvnode changes made above. */ 1146 if ((flags & MNT_FORCE) && 1147 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1148 if (mp->mnt_vnodecovered != NULL) 1149 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1150 if (rootvnode == NULL) { 1151 rootvnode = fsrootvp; 1152 vref(rootvnode); 1153 } 1154 vput(fsrootvp); 1155 } 1156 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 1157 (void) vfs_allocate_syncvnode(mp); 1158 MNT_ILOCK(mp); 1159 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1160 mp->mnt_flag |= async_flag; 1161 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1162 if (mp->mnt_kern_flag & MNTK_MWAIT) 1163 wakeup(mp); 1164 MNT_IUNLOCK(mp); 1165 if (coveredvp) 1166 VOP_UNLOCK(coveredvp, 0, td); 1167 return (error); 1168 } 1169 mtx_lock(&mountlist_mtx); 1170 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1171 mtx_unlock(&mountlist_mtx); 1172 if (coveredvp != NULL) { 1173 coveredvp->v_mountedhere = NULL; 1174 vput(coveredvp); 1175 } 1176 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1177 vfs_mount_destroy(mp, td); 1178 return (0); 1179} 1180 1181/* 1182 * --------------------------------------------------------------------- 1183 * Mounting of root filesystem 1184 * 1185 */ 1186 1187struct root_hold_token { 1188 const char *who; 1189 LIST_ENTRY(root_hold_token) list; 1190}; 1191 1192static LIST_HEAD(, root_hold_token) root_holds = 1193 LIST_HEAD_INITIALIZER(&root_holds); 1194 1195struct root_hold_token * 1196root_mount_hold(const char *identifier) 1197{ 1198 struct root_hold_token *h; 1199 1200 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1201 h->who = identifier; 1202 mtx_lock(&mountlist_mtx); 1203 LIST_INSERT_HEAD(&root_holds, h, list); 1204 mtx_unlock(&mountlist_mtx); 1205 return (h); 1206} 1207 1208void 1209root_mount_rel(struct root_hold_token *h) 1210{ 1211 1212 mtx_lock(&mountlist_mtx); 1213 LIST_REMOVE(h, list); 1214 wakeup(&root_holds); 1215 mtx_unlock(&mountlist_mtx); 1216 free(h, M_DEVBUF); 1217} 1218 1219static void 1220root_mount_wait(void) 1221{ 1222 struct root_hold_token *h; 1223 1224 for (;;) { 1225 DROP_GIANT(); 1226 g_waitidle(); 1227 PICKUP_GIANT(); 1228 mtx_lock(&mountlist_mtx); 1229 if (LIST_EMPTY(&root_holds)) { 1230 mtx_unlock(&mountlist_mtx); 1231 break; 1232 } 1233 printf("Root mount waiting for:"); 1234 LIST_FOREACH(h, &root_holds, list) 1235 printf(" %s", h->who); 1236 printf("\n"); 1237 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1238 hz); 1239 } 1240} 1241 1242static void 1243set_rootvnode(struct thread *td) 1244{ 1245 struct proc *p; 1246 1247 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1248 panic("Cannot find root vnode"); 1249 1250 p = td->td_proc; 1251 FILEDESC_LOCK(p->p_fd); 1252 1253 if (p->p_fd->fd_cdir != NULL) 1254 vrele(p->p_fd->fd_cdir); 1255 p->p_fd->fd_cdir = rootvnode; 1256 VREF(rootvnode); 1257 1258 if (p->p_fd->fd_rdir != NULL) 1259 vrele(p->p_fd->fd_rdir); 1260 p->p_fd->fd_rdir = rootvnode; 1261 VREF(rootvnode); 1262 1263 FILEDESC_UNLOCK(p->p_fd); 1264 1265 VOP_UNLOCK(rootvnode, 0, td); 1266} 1267 1268/* 1269 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1270 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1271 */ 1272 1273static void 1274devfs_first(void) 1275{ 1276 struct thread *td = curthread; 1277 struct vfsoptlist *opts; 1278 struct vfsconf *vfsp; 1279 struct mount *mp = NULL; 1280 int error; 1281 1282 vfsp = vfs_byname("devfs"); 1283 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1284 if (vfsp == NULL) 1285 return; 1286 1287 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1288 1289 error = VFS_MOUNT(mp, td); 1290 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1291 if (error) 1292 return; 1293 1294 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1295 TAILQ_INIT(opts); 1296 mp->mnt_opt = opts; 1297 1298 mtx_lock(&mountlist_mtx); 1299 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1300 mtx_unlock(&mountlist_mtx); 1301 1302 set_rootvnode(td); 1303 1304 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1305 if (error) 1306 printf("kern_symlink /dev -> / returns %d\n", error); 1307} 1308 1309/* 1310 * Surgically move our devfs to be mounted on /dev. 1311 */ 1312 1313static void 1314devfs_fixup(struct thread *td) 1315{ 1316 struct nameidata nd; 1317 int error; 1318 struct vnode *vp, *dvp; 1319 struct mount *mp; 1320 1321 /* Remove our devfs mount from the mountlist and purge the cache */ 1322 mtx_lock(&mountlist_mtx); 1323 mp = TAILQ_FIRST(&mountlist); 1324 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1325 mtx_unlock(&mountlist_mtx); 1326 cache_purgevfs(mp); 1327 1328 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1329 VI_LOCK(dvp); 1330 dvp->v_iflag &= ~VI_MOUNT; 1331 dvp->v_mountedhere = NULL; 1332 VI_UNLOCK(dvp); 1333 1334 /* Set up the real rootvnode, and purge the cache */ 1335 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1336 set_rootvnode(td); 1337 cache_purgevfs(rootvnode->v_mount); 1338 1339 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1340 error = namei(&nd); 1341 if (error) { 1342 printf("Lookup of /dev for devfs, error: %d\n", error); 1343 return; 1344 } 1345 NDFREE(&nd, NDF_ONLY_PNBUF); 1346 vp = nd.ni_vp; 1347 if (vp->v_type != VDIR) { 1348 vput(vp); 1349 } 1350 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1351 if (error) { 1352 vput(vp); 1353 } 1354 cache_purge(vp); 1355 mp->mnt_vnodecovered = vp; 1356 vp->v_mountedhere = mp; 1357 mtx_lock(&mountlist_mtx); 1358 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1359 mtx_unlock(&mountlist_mtx); 1360 VOP_UNLOCK(vp, 0, td); 1361 vput(dvp); 1362 vfs_unbusy(mp, td); 1363 1364 /* Unlink the no longer needed /dev/dev -> / symlink */ 1365 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1366} 1367 1368/* 1369 * Report errors during filesystem mounting. 1370 */ 1371void 1372vfs_mount_error(struct mount *mp, const char *fmt, ...) 1373{ 1374 struct vfsoptlist *moptlist = mp->mnt_optnew; 1375 va_list ap; 1376 int error, len; 1377 char *errmsg; 1378 1379 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1380 if (error || errmsg == NULL || len <= 0) 1381 return; 1382 1383 va_start(ap, fmt); 1384 vsnprintf(errmsg, (size_t)len, fmt, ap); 1385 va_end(ap); 1386} 1387 1388/* 1389 * Find and mount the root filesystem 1390 */ 1391void 1392vfs_mountroot(void) 1393{ 1394 char *cp; 1395 int error, i, asked = 0; 1396 1397 root_mount_wait(); 1398 1399 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1400 NULL, NULL, mount_init, mount_fini, 1401 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1402 devfs_first(); 1403 1404 /* 1405 * We are booted with instructions to prompt for the root filesystem. 1406 */ 1407 if (boothowto & RB_ASKNAME) { 1408 if (!vfs_mountroot_ask()) 1409 return; 1410 asked = 1; 1411 } 1412 1413 /* 1414 * The root filesystem information is compiled in, and we are 1415 * booted with instructions to use it. 1416 */ 1417 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1418 if (!vfs_mountroot_try(ctrootdevname)) 1419 return; 1420 ctrootdevname = NULL; 1421 } 1422 1423 /* 1424 * We've been given the generic "use CDROM as root" flag. This is 1425 * necessary because one media may be used in many different 1426 * devices, so we need to search for them. 1427 */ 1428 if (boothowto & RB_CDROM) { 1429 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1430 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1431 return; 1432 } 1433 } 1434 1435 /* 1436 * Try to use the value read by the loader from /etc/fstab, or 1437 * supplied via some other means. This is the preferred 1438 * mechanism. 1439 */ 1440 cp = getenv("vfs.root.mountfrom"); 1441 if (cp != NULL) { 1442 error = vfs_mountroot_try(cp); 1443 freeenv(cp); 1444 if (!error) 1445 return; 1446 } 1447 1448 /* 1449 * Try values that may have been computed by code during boot 1450 */ 1451 if (!vfs_mountroot_try(rootdevnames[0])) 1452 return; 1453 if (!vfs_mountroot_try(rootdevnames[1])) 1454 return; 1455 1456 /* 1457 * If we (still) have a compiled-in default, try it. 1458 */ 1459 if (ctrootdevname != NULL) 1460 if (!vfs_mountroot_try(ctrootdevname)) 1461 return; 1462 /* 1463 * Everything so far has failed, prompt on the console if we haven't 1464 * already tried that. 1465 */ 1466 if (!asked) 1467 if (!vfs_mountroot_ask()) 1468 return; 1469 1470 panic("Root mount failed, startup aborted."); 1471} 1472 1473/* 1474 * Mount (mountfrom) as the root filesystem. 1475 */ 1476static int 1477vfs_mountroot_try(const char *mountfrom) 1478{ 1479 struct mount *mp; 1480 char *vfsname, *path; 1481 time_t timebase; 1482 int error; 1483 char patt[32]; 1484 1485 vfsname = NULL; 1486 path = NULL; 1487 mp = NULL; 1488 error = EINVAL; 1489 1490 if (mountfrom == NULL) 1491 return (error); /* don't complain */ 1492 printf("Trying to mount root from %s\n", mountfrom); 1493 1494 /* parse vfs name and path */ 1495 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1496 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1497 vfsname[0] = path[0] = 0; 1498 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1499 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1500 goto out; 1501 1502 if (path[0] == '\0') 1503 strcpy(path, ROOTNAME); 1504 1505 error = kernel_vmount( 1506 MNT_RDONLY | MNT_ROOTFS, 1507 "fstype", vfsname, 1508 "fspath", "/", 1509 "from", path, 1510 NULL); 1511 if (error == 0) { 1512 /* 1513 * We mount devfs prior to mounting the / FS, so the first 1514 * entry will typically be devfs. 1515 */ 1516 mp = TAILQ_FIRST(&mountlist); 1517 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1518 1519 /* 1520 * Iterate over all currently mounted file systems and use 1521 * the time stamp found to check and/or initialize the RTC. 1522 * Typically devfs has no time stamp and the only other FS 1523 * is the actual / FS. 1524 * Call inittodr() only once and pass it the largest of the 1525 * timestamps we encounter. 1526 */ 1527 timebase = 0; 1528 do { 1529 if (mp->mnt_time > timebase) 1530 timebase = mp->mnt_time; 1531 mp = TAILQ_NEXT(mp, mnt_list); 1532 } while (mp != NULL); 1533 inittodr(timebase); 1534 1535 devfs_fixup(curthread); 1536 } 1537out: 1538 free(path, M_MOUNT); 1539 free(vfsname, M_MOUNT); 1540 return (error); 1541} 1542 1543/* 1544 * --------------------------------------------------------------------- 1545 * Interactive root filesystem selection code. 1546 */ 1547 1548static int 1549vfs_mountroot_ask(void) 1550{ 1551 char name[128]; 1552 1553 for(;;) { 1554 printf("\nManual root filesystem specification:\n"); 1555 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1556#if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1557 printf(" eg. ufs:da0s1a\n"); 1558#else 1559 printf(" eg. ufs:/dev/da0a\n"); 1560#endif 1561 printf(" ? List valid disk boot devices\n"); 1562 printf(" <empty line> Abort manual input\n"); 1563 printf("\nmountroot> "); 1564 gets(name, sizeof(name), 1); 1565 if (name[0] == '\0') 1566 return (1); 1567 if (name[0] == '?') { 1568 printf("\nList of GEOM managed disk devices:\n "); 1569 g_dev_print(); 1570 continue; 1571 } 1572 if (!vfs_mountroot_try(name)) 1573 return (0); 1574 } 1575} 1576 1577/* 1578 * --------------------------------------------------------------------- 1579 * Functions for querying mount options/arguments from filesystems. 1580 */ 1581 1582/* 1583 * Check that no unknown options are given 1584 */ 1585int 1586vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1587{ 1588 struct vfsopt *opt; 1589 const char **t, *p; 1590 1591 1592 TAILQ_FOREACH(opt, opts, link) { 1593 p = opt->name; 1594 if (p[0] == 'n' && p[1] == 'o') 1595 p += 2; 1596 for(t = global_opts; *t != NULL; t++) 1597 if (!strcmp(*t, p)) 1598 break; 1599 if (*t != NULL) 1600 continue; 1601 for(t = legal; *t != NULL; t++) 1602 if (!strcmp(*t, p)) 1603 break; 1604 if (*t != NULL) 1605 continue; 1606 printf("mount option <%s> is unknown\n", p); 1607 return (EINVAL); 1608 } 1609 return (0); 1610} 1611 1612/* 1613 * Get a mount option by its name. 1614 * 1615 * Return 0 if the option was found, ENOENT otherwise. 1616 * If len is non-NULL it will be filled with the length 1617 * of the option. If buf is non-NULL, it will be filled 1618 * with the address of the option. 1619 */ 1620int 1621vfs_getopt(opts, name, buf, len) 1622 struct vfsoptlist *opts; 1623 const char *name; 1624 void **buf; 1625 int *len; 1626{ 1627 struct vfsopt *opt; 1628 1629 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1630 1631 TAILQ_FOREACH(opt, opts, link) { 1632 if (strcmp(name, opt->name) == 0) { 1633 if (len != NULL) 1634 *len = opt->len; 1635 if (buf != NULL) 1636 *buf = opt->value; 1637 return (0); 1638 } 1639 } 1640 return (ENOENT); 1641} 1642 1643static int 1644vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1645{ 1646 struct vfsopt *opt; 1647 int i; 1648 1649 if (opts == NULL) 1650 return (-1); 1651 1652 i = 0; 1653 TAILQ_FOREACH(opt, opts, link) { 1654 if (strcmp(name, opt->name) == 0) 1655 return (i); 1656 ++i; 1657 } 1658 return (-1); 1659} 1660 1661char * 1662vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1663{ 1664 struct vfsopt *opt; 1665 1666 *error = 0; 1667 TAILQ_FOREACH(opt, opts, link) { 1668 if (strcmp(name, opt->name) != 0) 1669 continue; 1670 if (((char *)opt->value)[opt->len - 1] != '\0') { 1671 *error = EINVAL; 1672 return (NULL); 1673 } 1674 return (opt->value); 1675 } 1676 return (NULL); 1677} 1678 1679int 1680vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1681{ 1682 struct vfsopt *opt; 1683 1684 TAILQ_FOREACH(opt, opts, link) { 1685 if (strcmp(name, opt->name) == 0) { 1686 if (w != NULL) 1687 *w |= val; 1688 return (1); 1689 } 1690 } 1691 if (w != NULL) 1692 *w &= ~val; 1693 return (0); 1694} 1695 1696int 1697vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1698{ 1699 va_list ap; 1700 struct vfsopt *opt; 1701 int ret; 1702 1703 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1704 1705 TAILQ_FOREACH(opt, opts, link) { 1706 if (strcmp(name, opt->name) != 0) 1707 continue; 1708 if (((char *)opt->value)[opt->len - 1] != '\0') 1709 return (0); 1710 va_start(ap, fmt); 1711 ret = vsscanf(opt->value, fmt, ap); 1712 va_end(ap); 1713 return (ret); 1714 } 1715 return (0); 1716} 1717 1718/* 1719 * Find and copy a mount option. 1720 * 1721 * The size of the buffer has to be specified 1722 * in len, if it is not the same length as the 1723 * mount option, EINVAL is returned. 1724 * Returns ENOENT if the option is not found. 1725 */ 1726int 1727vfs_copyopt(opts, name, dest, len) 1728 struct vfsoptlist *opts; 1729 const char *name; 1730 void *dest; 1731 int len; 1732{ 1733 struct vfsopt *opt; 1734 1735 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1736 1737 TAILQ_FOREACH(opt, opts, link) { 1738 if (strcmp(name, opt->name) == 0) { 1739 if (len != opt->len) 1740 return (EINVAL); 1741 bcopy(opt->value, dest, opt->len); 1742 return (0); 1743 } 1744 } 1745 return (ENOENT); 1746} 1747 1748/* 1749 * This is a helper function for filesystems to traverse their 1750 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1751 */ 1752 1753struct vnode * 1754__mnt_vnode_next(struct vnode **mvp, struct mount *mp) 1755{ 1756 struct vnode *vp; 1757 1758 mtx_assert(MNT_MTX(mp), MA_OWNED); 1759 1760 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 1761 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 1762 while (vp != NULL && vp->v_type == VMARKER) 1763 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1764 1765 /* Check if we are done */ 1766 if (vp == NULL) { 1767 __mnt_vnode_markerfree(mvp, mp); 1768 return (NULL); 1769 } 1770 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 1771 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 1772 return (vp); 1773} 1774 1775struct vnode * 1776__mnt_vnode_first(struct vnode **mvp, struct mount *mp) 1777{ 1778 struct vnode *vp; 1779 1780 mtx_assert(MNT_MTX(mp), MA_OWNED); 1781 1782 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1783 while (vp != NULL && vp->v_type == VMARKER) 1784 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1785 1786 /* Check if we are done */ 1787 if (vp == NULL) { 1788 *mvp = NULL; 1789 return (NULL); 1790 } 1791 mp->mnt_holdcnt++; 1792 MNT_IUNLOCK(mp); 1793 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 1794 M_VNODE_MARKER, 1795 M_WAITOK | M_ZERO); 1796 MNT_ILOCK(mp); 1797 (*mvp)->v_type = VMARKER; 1798 1799 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1800 while (vp != NULL && vp->v_type == VMARKER) 1801 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1802 1803 /* Check if we are done */ 1804 if (vp == NULL) { 1805 MNT_IUNLOCK(mp); 1806 free(*mvp, M_VNODE_MARKER); 1807 MNT_ILOCK(mp); 1808 *mvp = NULL; 1809 mp->mnt_holdcnt--; 1810 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 1811 wakeup(&mp->mnt_holdcnt); 1812 return (NULL); 1813 } 1814 mp->mnt_markercnt++; 1815 (*mvp)->v_mount = mp; 1816 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 1817 return (vp); 1818} 1819 1820 1821void 1822__mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 1823{ 1824 1825 if (*mvp == NULL) 1826 return; 1827 1828 mtx_assert(MNT_MTX(mp), MA_OWNED); 1829 1830 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 1831 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 1832 MNT_IUNLOCK(mp); 1833 free(*mvp, M_VNODE_MARKER); 1834 MNT_ILOCK(mp); 1835 *mvp = NULL; 1836 1837 mp->mnt_markercnt--; 1838 mp->mnt_holdcnt--; 1839 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 1840 wakeup(&mp->mnt_holdcnt); 1841} 1842 1843 1844int 1845__vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 1846{ 1847 int error; 1848 1849 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 1850 if (sbp != &mp->mnt_stat) 1851 *sbp = mp->mnt_stat; 1852 return (error); 1853} 1854 1855void 1856vfs_mountedfrom(struct mount *mp, const char *from) 1857{ 1858 1859 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1860 strlcpy(mp->mnt_stat.f_mntfromname, from, 1861 sizeof mp->mnt_stat.f_mntfromname); 1862} 1863 1864/* 1865 * --------------------------------------------------------------------- 1866 * This is the api for building mount args and mounting filesystems from 1867 * inside the kernel. 1868 * 1869 * The API works by accumulation of individual args. First error is 1870 * latched. 1871 * 1872 * XXX: should be documented in new manpage kernel_mount(9) 1873 */ 1874 1875/* A memory allocation which must be freed when we are done */ 1876struct mntaarg { 1877 SLIST_ENTRY(mntaarg) next; 1878}; 1879 1880/* The header for the mount arguments */ 1881struct mntarg { 1882 struct iovec *v; 1883 int len; 1884 int error; 1885 SLIST_HEAD(, mntaarg) list; 1886}; 1887 1888/* 1889 * Add a boolean argument. 1890 * 1891 * flag is the boolean value. 1892 * name must start with "no". 1893 */ 1894struct mntarg * 1895mount_argb(struct mntarg *ma, int flag, const char *name) 1896{ 1897 1898 KASSERT(name[0] == 'n' && name[1] == 'o', 1899 ("mount_argb(...,%s): name must start with 'no'", name)); 1900 1901 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1902} 1903 1904/* 1905 * Add an argument printf style 1906 */ 1907struct mntarg * 1908mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1909{ 1910 va_list ap; 1911 struct mntaarg *maa; 1912 struct sbuf *sb; 1913 int len; 1914 1915 if (ma == NULL) { 1916 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1917 SLIST_INIT(&ma->list); 1918 } 1919 if (ma->error) 1920 return (ma); 1921 1922 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1923 M_MOUNT, M_WAITOK); 1924 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1925 ma->v[ma->len].iov_len = strlen(name) + 1; 1926 ma->len++; 1927 1928 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 1929 va_start(ap, fmt); 1930 sbuf_vprintf(sb, fmt, ap); 1931 va_end(ap); 1932 sbuf_finish(sb); 1933 len = sbuf_len(sb) + 1; 1934 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1935 SLIST_INSERT_HEAD(&ma->list, maa, next); 1936 bcopy(sbuf_data(sb), maa + 1, len); 1937 sbuf_delete(sb); 1938 1939 ma->v[ma->len].iov_base = maa + 1; 1940 ma->v[ma->len].iov_len = len; 1941 ma->len++; 1942 1943 return (ma); 1944} 1945 1946/* 1947 * Add an argument which is a userland string. 1948 */ 1949struct mntarg * 1950mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1951{ 1952 struct mntaarg *maa; 1953 char *tbuf; 1954 1955 if (val == NULL) 1956 return (ma); 1957 if (ma == NULL) { 1958 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1959 SLIST_INIT(&ma->list); 1960 } 1961 if (ma->error) 1962 return (ma); 1963 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1964 SLIST_INSERT_HEAD(&ma->list, maa, next); 1965 tbuf = (void *)(maa + 1); 1966 ma->error = copyinstr(val, tbuf, len, NULL); 1967 return (mount_arg(ma, name, tbuf, -1)); 1968} 1969 1970/* 1971 * Plain argument. 1972 * 1973 * If length is -1, use printf. 1974 */ 1975struct mntarg * 1976mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1977{ 1978 1979 if (ma == NULL) { 1980 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1981 SLIST_INIT(&ma->list); 1982 } 1983 if (ma->error) 1984 return (ma); 1985 1986 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1987 M_MOUNT, M_WAITOK); 1988 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1989 ma->v[ma->len].iov_len = strlen(name) + 1; 1990 ma->len++; 1991 1992 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1993 if (len < 0) 1994 ma->v[ma->len].iov_len = strlen(val) + 1; 1995 else 1996 ma->v[ma->len].iov_len = len; 1997 ma->len++; 1998 return (ma); 1999} 2000 2001/* 2002 * Free a mntarg structure 2003 */ 2004static void 2005free_mntarg(struct mntarg *ma) 2006{ 2007 struct mntaarg *maa; 2008 2009 while (!SLIST_EMPTY(&ma->list)) { 2010 maa = SLIST_FIRST(&ma->list); 2011 SLIST_REMOVE_HEAD(&ma->list, next); 2012 free(maa, M_MOUNT); 2013 } 2014 free(ma->v, M_MOUNT); 2015 free(ma, M_MOUNT); 2016} 2017 2018/* 2019 * Mount a filesystem 2020 */ 2021int 2022kernel_mount(struct mntarg *ma, int flags) 2023{ 2024 struct uio auio; 2025 int error; 2026 2027 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2028 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2029 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2030 2031 auio.uio_iov = ma->v; 2032 auio.uio_iovcnt = ma->len; 2033 auio.uio_segflg = UIO_SYSSPACE; 2034 2035 error = ma->error; 2036 if (!error) 2037 error = vfs_donmount(curthread, flags, &auio); 2038 free_mntarg(ma); 2039 return (error); 2040} 2041 2042/* 2043 * A printflike function to mount a filesystem. 2044 */ 2045int 2046kernel_vmount(int flags, ...) 2047{ 2048 struct mntarg *ma = NULL; 2049 va_list ap; 2050 const char *cp; 2051 const void *vp; 2052 int error; 2053 2054 va_start(ap, flags); 2055 for (;;) { 2056 cp = va_arg(ap, const char *); 2057 if (cp == NULL) 2058 break; 2059 vp = va_arg(ap, const void *); 2060 ma = mount_arg(ma, cp, vp, -1); 2061 } 2062 va_end(ap); 2063 2064 error = kernel_mount(ma, flags); 2065 return (error); 2066} 2067