vfs_mount.c revision 157343
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 157343 2006-03-31 23:38:15Z 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 struct vnode *vp; 538 539 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 540 vprint("", vp); 541 panic("unmount: dangling vnode"); 542 } 543 MNT_ILOCK(mp); 544 if (mp->mnt_kern_flag & MNTK_MWAIT) 545 wakeup(mp); 546 if (mp->mnt_writeopcount != 0) 547 panic("vfs_mount_destroy: nonzero writeopcount"); 548 if (mp->mnt_secondary_writes != 0) 549 panic("vfs_mount_destroy: nonzero secondary_writes"); 550 if (mp->mnt_nvnodelistsize != 0) 551 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 552 mp->mnt_writeopcount = -1000; 553 mp->mnt_nvnodelistsize = -1000; 554 mp->mnt_secondary_writes = -1000; 555 MNT_IUNLOCK(mp); 556#ifdef MAC 557 mac_destroy_mount(mp); 558#endif 559 if (mp->mnt_opt != NULL) 560 vfs_freeopts(mp->mnt_opt); 561 crfree(mp->mnt_cred); 562 uma_zfree(mount_zone, mp); 563} 564 565static int 566vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 567{ 568 struct vfsoptlist *optlist; 569 struct vfsopt *opt; 570 char *fstype, *fspath, *errmsg; 571 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 572 573 errmsg_len = 0; 574 errmsg_pos = -1; 575 576 error = vfs_buildopts(fsoptions, &optlist); 577 if (error) 578 return (error); 579 580 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 581 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 582 else 583 errmsg_len = 0; 584 585 /* 586 * We need these two options before the others, 587 * and they are mandatory for any filesystem. 588 * Ensure they are NUL terminated as well. 589 */ 590 fstypelen = 0; 591 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 592 if (error || fstype[fstypelen - 1] != '\0') { 593 error = EINVAL; 594 if (errmsg != NULL) 595 strncpy(errmsg, "Invalid fstype", errmsg_len); 596 goto bail; 597 } 598 fspathlen = 0; 599 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 600 if (error || fspath[fspathlen - 1] != '\0') { 601 error = EINVAL; 602 if (errmsg != NULL) 603 strncpy(errmsg, "Invalid fspath", errmsg_len); 604 goto bail; 605 } 606 607 /* 608 * We need to see if we have the "update" option 609 * before we call vfs_domount(), since vfs_domount() has special 610 * logic based on MNT_UPDATE. This is very important 611 * when we want to update the root filesystem. 612 */ 613 TAILQ_FOREACH(opt, optlist, link) { 614 if (strcmp(opt->name, "update") == 0) 615 fsflags |= MNT_UPDATE; 616 else if (strcmp(opt->name, "async") == 0) 617 fsflags |= MNT_ASYNC; 618 else if (strcmp(opt->name, "force") == 0) 619 fsflags |= MNT_FORCE; 620 else if (strcmp(opt->name, "multilabel") == 0) 621 fsflags |= MNT_MULTILABEL; 622 else if (strcmp(opt->name, "noasync") == 0) 623 fsflags &= ~MNT_ASYNC; 624 else if (strcmp(opt->name, "noatime") == 0) 625 fsflags |= MNT_NOATIME; 626 else if (strcmp(opt->name, "noclusterr") == 0) 627 fsflags |= MNT_NOCLUSTERR; 628 else if (strcmp(opt->name, "noclusterw") == 0) 629 fsflags |= MNT_NOCLUSTERW; 630 else if (strcmp(opt->name, "noexec") == 0) 631 fsflags |= MNT_NOEXEC; 632 else if (strcmp(opt->name, "nosuid") == 0) 633 fsflags |= MNT_NOSUID; 634 else if (strcmp(opt->name, "nosymfollow") == 0) 635 fsflags |= MNT_NOSYMFOLLOW; 636 else if (strcmp(opt->name, "noro") == 0 || 637 strcmp(opt->name, "rw") == 0) 638 fsflags &= ~MNT_RDONLY; 639 else if (strcmp(opt->name, "ro") == 0 || 640 strcmp(opt->name, "rdonly") == 0) 641 fsflags |= MNT_RDONLY; 642 else if (strcmp(opt->name, "snapshot") == 0) 643 fsflags |= MNT_SNAPSHOT; 644 else if (strcmp(opt->name, "suiddir") == 0) 645 fsflags |= MNT_SUIDDIR; 646 else if (strcmp(opt->name, "sync") == 0) 647 fsflags |= MNT_SYNCHRONOUS; 648 else if (strcmp(opt->name, "union") == 0) 649 fsflags |= MNT_UNION; 650 } 651 652 /* 653 * Be ultra-paranoid about making sure the type and fspath 654 * variables will fit in our mp buffers, including the 655 * terminating NUL. 656 */ 657 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 658 error = ENAMETOOLONG; 659 goto bail; 660 } 661 662 mtx_lock(&Giant); 663 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 664 mtx_unlock(&Giant); 665bail: 666 /* copyout the errmsg */ 667 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 668 && errmsg_len > 0 && errmsg != NULL) { 669 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 670 strncpy(fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 671 errmsg, 672 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 673 } else { 674 copystr(errmsg, 675 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 676 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len, 677 NULL); 678 } 679 } 680 681 if (error != 0) 682 vfs_freeopts(optlist); 683 return (error); 684} 685 686/* 687 * --------------------------------------------------------------------- 688 * Old mount API. 689 */ 690#ifndef _SYS_SYSPROTO_H_ 691struct mount_args { 692 char *type; 693 char *path; 694 int flags; 695 caddr_t data; 696}; 697#endif 698/* ARGSUSED */ 699int 700mount(td, uap) 701 struct thread *td; 702 struct mount_args /* { 703 char *type; 704 char *path; 705 int flags; 706 caddr_t data; 707 } */ *uap; 708{ 709 char *fstype; 710 struct vfsconf *vfsp = NULL; 711 struct mntarg *ma = NULL; 712 int error; 713 714 /* Kick out MNT_ROOTFS early as it is legal internally */ 715 uap->flags &= ~MNT_ROOTFS; 716 717 if (uap->data == NULL) 718 return (EINVAL); 719 720 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 721 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 722 if (!error) { 723 mtx_lock(&Giant); /* XXX ? */ 724 vfsp = vfs_byname_kld(fstype, td, &error); 725 mtx_unlock(&Giant); 726 } 727 free(fstype, M_TEMP); 728 if (error) 729 return (error); 730 if (vfsp == NULL) 731 return (ENOENT); 732 if (vfsp->vfc_vfsops->vfs_cmount == NULL) 733 return (EOPNOTSUPP); 734 735 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 736 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 737 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 738 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 739 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 740 741 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 742 return (error); 743} 744 745 746/* 747 * vfs_domount(): actually attempt a filesystem mount. 748 */ 749static int 750vfs_domount( 751 struct thread *td, /* Flags common to all filesystems. */ 752 const char *fstype, /* Filesystem type. */ 753 char *fspath, /* Mount path. */ 754 int fsflags, /* Flags common to all filesystems. */ 755 void *fsdata /* Options local to the filesystem. */ 756 ) 757{ 758 struct vnode *vp; 759 struct mount *mp; 760 struct vfsconf *vfsp; 761 int error, flag = 0, kern_flag = 0; 762 struct vattr va; 763 struct nameidata nd; 764 765 mtx_assert(&Giant, MA_OWNED); 766 /* 767 * Be ultra-paranoid about making sure the type and fspath 768 * variables will fit in our mp buffers, including the 769 * terminating NUL. 770 */ 771 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 772 return (ENAMETOOLONG); 773 774 if (jailed(td->td_ucred)) 775 return (EPERM); 776 if (usermount == 0) { 777 if ((error = suser(td)) != 0) 778 return (error); 779 } 780 781 /* 782 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 783 */ 784 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 785 if ((error = suser(td)) != 0) 786 return (error); 787 } 788 /* 789 * Silently enforce MNT_NOSUID and MNT_USER for 790 * unprivileged users. 791 */ 792 if (suser(td) != 0) 793 fsflags |= MNT_NOSUID | MNT_USER; 794 795 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 796 vfsp = NULL; 797 if ((fsflags & MNT_UPDATE) == 0) { 798 /* Don't try to load KLDs if we're mounting the root. */ 799 if (fsflags & MNT_ROOTFS) 800 vfsp = vfs_byname(fstype); 801 else 802 vfsp = vfs_byname_kld(fstype, td, &error); 803 if (vfsp == NULL) 804 return (ENODEV); 805 } 806 /* 807 * Get vnode to be covered 808 */ 809 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 810 if ((error = namei(&nd)) != 0) 811 return (error); 812 NDFREE(&nd, NDF_ONLY_PNBUF); 813 vp = nd.ni_vp; 814 if (fsflags & MNT_UPDATE) { 815 if ((vp->v_vflag & VV_ROOT) == 0) { 816 vput(vp); 817 return (EINVAL); 818 } 819 mp = vp->v_mount; 820 flag = mp->mnt_flag; 821 kern_flag = mp->mnt_kern_flag; 822 /* 823 * We only allow the filesystem to be reloaded if it 824 * is currently mounted read-only. 825 */ 826 if ((fsflags & MNT_RELOAD) && 827 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 828 vput(vp); 829 return (EOPNOTSUPP); /* Needs translation */ 830 } 831 /* 832 * Only privileged root, or (if MNT_USER is set) the user that 833 * did the original mount is permitted to update it. 834 */ 835 error = vfs_suser(mp, td); 836 if (error) { 837 vput(vp); 838 return (error); 839 } 840 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 841 vput(vp); 842 return (EBUSY); 843 } 844 VI_LOCK(vp); 845 if ((vp->v_iflag & VI_MOUNT) != 0 || 846 vp->v_mountedhere != NULL) { 847 VI_UNLOCK(vp); 848 vfs_unbusy(mp, td); 849 vput(vp); 850 return (EBUSY); 851 } 852 vp->v_iflag |= VI_MOUNT; 853 VI_UNLOCK(vp); 854 mp->mnt_flag |= fsflags & 855 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 856 VOP_UNLOCK(vp, 0, td); 857 mp->mnt_optnew = fsdata; 858 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 859 } else { 860 /* 861 * If the user is not root, ensure that they own the directory 862 * onto which we are attempting to mount. 863 */ 864 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 865 if (error) { 866 vput(vp); 867 return (error); 868 } 869 if (va.va_uid != td->td_ucred->cr_uid) { 870 if ((error = suser(td)) != 0) { 871 vput(vp); 872 return (error); 873 } 874 } 875 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 876 if (error != 0) { 877 vput(vp); 878 return (error); 879 } 880 if (vp->v_type != VDIR) { 881 vput(vp); 882 return (ENOTDIR); 883 } 884 VI_LOCK(vp); 885 if ((vp->v_iflag & VI_MOUNT) != 0 || 886 vp->v_mountedhere != NULL) { 887 VI_UNLOCK(vp); 888 vput(vp); 889 return (EBUSY); 890 } 891 vp->v_iflag |= VI_MOUNT; 892 VI_UNLOCK(vp); 893 894 /* 895 * Allocate and initialize the filesystem. 896 */ 897 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 898 VOP_UNLOCK(vp, 0, td); 899 900 /* XXXMAC: pass to vfs_mount_alloc? */ 901 mp->mnt_optnew = fsdata; 902 } 903 904 /* 905 * Set the mount level flags. 906 */ 907 if (fsflags & MNT_RDONLY) 908 mp->mnt_flag |= MNT_RDONLY; 909 mp->mnt_flag &=~ MNT_UPDATEMASK; 910 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS); 911 /* 912 * Mount the filesystem. 913 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 914 * get. No freeing of cn_pnbuf. 915 */ 916 error = VFS_MOUNT(mp, td); 917 if (!error) { 918 if (mp->mnt_opt != NULL) 919 vfs_freeopts(mp->mnt_opt); 920 mp->mnt_opt = mp->mnt_optnew; 921 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 922 } 923 /* 924 * Prevent external consumers of mount options from reading 925 * mnt_optnew. 926 */ 927 mp->mnt_optnew = NULL; 928 if (mp->mnt_flag & MNT_UPDATE) { 929 mp->mnt_flag &= 930 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 931 if (error) { 932 mp->mnt_flag = flag; 933 mp->mnt_kern_flag = kern_flag; 934 } 935 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 936 if (mp->mnt_syncer == NULL) 937 error = vfs_allocate_syncvnode(mp); 938 } else { 939 if (mp->mnt_syncer != NULL) 940 vrele(mp->mnt_syncer); 941 mp->mnt_syncer = NULL; 942 } 943 vfs_unbusy(mp, td); 944 VI_LOCK(vp); 945 vp->v_iflag &= ~VI_MOUNT; 946 VI_UNLOCK(vp); 947 vrele(vp); 948 return (error); 949 } 950 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 951 /* 952 * Put the new filesystem on the mount list after root. 953 */ 954 cache_purge(vp); 955 if (!error) { 956 struct vnode *newdp; 957 958 VI_LOCK(vp); 959 vp->v_iflag &= ~VI_MOUNT; 960 VI_UNLOCK(vp); 961 vp->v_mountedhere = mp; 962 mtx_lock(&mountlist_mtx); 963 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 964 mtx_unlock(&mountlist_mtx); 965 vfs_event_signal(NULL, VQ_MOUNT, 0); 966 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 967 panic("mount: lost mount"); 968 mountcheckdirs(vp, newdp); 969 vput(newdp); 970 VOP_UNLOCK(vp, 0, td); 971 if ((mp->mnt_flag & MNT_RDONLY) == 0) 972 error = vfs_allocate_syncvnode(mp); 973 vfs_unbusy(mp, td); 974 if (error) 975 vrele(vp); 976 } else { 977 VI_LOCK(vp); 978 vp->v_iflag &= ~VI_MOUNT; 979 VI_UNLOCK(vp); 980 vfs_mount_destroy(mp, td); 981 vput(vp); 982 } 983 return (error); 984} 985 986/* 987 * --------------------------------------------------------------------- 988 * Unmount a filesystem. 989 * 990 * Note: unmount takes a path to the vnode mounted on as argument, 991 * not special file (as before). 992 */ 993#ifndef _SYS_SYSPROTO_H_ 994struct unmount_args { 995 char *path; 996 int flags; 997}; 998#endif 999/* ARGSUSED */ 1000int 1001unmount(td, uap) 1002 struct thread *td; 1003 register struct unmount_args /* { 1004 char *path; 1005 int flags; 1006 } */ *uap; 1007{ 1008 struct mount *mp; 1009 char *pathbuf; 1010 int error, id0, id1; 1011 1012 if (jailed(td->td_ucred)) 1013 return (EPERM); 1014 if (usermount == 0) { 1015 if ((error = suser(td)) != 0) 1016 return (error); 1017 } 1018 1019 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1020 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1021 if (error) { 1022 free(pathbuf, M_TEMP); 1023 return (error); 1024 } 1025 if (uap->flags & MNT_BYFSID) { 1026 /* Decode the filesystem ID. */ 1027 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1028 free(pathbuf, M_TEMP); 1029 return (EINVAL); 1030 } 1031 1032 mtx_lock(&mountlist_mtx); 1033 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1034 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1035 mp->mnt_stat.f_fsid.val[1] == id1) 1036 break; 1037 } 1038 mtx_unlock(&mountlist_mtx); 1039 } else { 1040 mtx_lock(&mountlist_mtx); 1041 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1042 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1043 break; 1044 } 1045 mtx_unlock(&mountlist_mtx); 1046 } 1047 free(pathbuf, M_TEMP); 1048 if (mp == NULL) { 1049 /* 1050 * Previously we returned ENOENT for a nonexistent path and 1051 * EINVAL for a non-mountpoint. We cannot tell these apart 1052 * now, so in the !MNT_BYFSID case return the more likely 1053 * EINVAL for compatibility. 1054 */ 1055 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1056 } 1057 1058 /* 1059 * Only privileged root, or (if MNT_USER is set) the user that did the 1060 * original mount is permitted to unmount this filesystem. 1061 */ 1062 error = vfs_suser(mp, td); 1063 if (error) 1064 return (error); 1065 1066 /* 1067 * Don't allow unmounting the root filesystem. 1068 */ 1069 if (mp->mnt_flag & MNT_ROOTFS) 1070 return (EINVAL); 1071 mtx_lock(&Giant); 1072 error = dounmount(mp, uap->flags, td); 1073 mtx_unlock(&Giant); 1074 return (error); 1075} 1076 1077/* 1078 * Do the actual filesystem unmount. 1079 */ 1080int 1081dounmount(mp, flags, td) 1082 struct mount *mp; 1083 int flags; 1084 struct thread *td; 1085{ 1086 struct vnode *coveredvp, *fsrootvp; 1087 int error; 1088 int async_flag; 1089 1090 mtx_assert(&Giant, MA_OWNED); 1091 1092 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 1093 vn_lock(coveredvp, LK_EXCLUSIVE | LK_RETRY, td); 1094 MNT_ILOCK(mp); 1095 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1096 MNT_IUNLOCK(mp); 1097 if (coveredvp) 1098 VOP_UNLOCK(coveredvp, 0, td); 1099 return (EBUSY); 1100 } 1101 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1102 /* Allow filesystems to detect that a forced unmount is in progress. */ 1103 if (flags & MNT_FORCE) 1104 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1105 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1106 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1107 if (error) { 1108 MNT_ILOCK(mp); 1109 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1110 if (mp->mnt_kern_flag & MNTK_MWAIT) 1111 wakeup(mp); 1112 MNT_IUNLOCK(mp); 1113 if (coveredvp) 1114 VOP_UNLOCK(coveredvp, 0, td); 1115 return (error); 1116 } 1117 vn_start_write(NULL, &mp, V_WAIT); 1118 1119 if (mp->mnt_flag & MNT_EXPUBLIC) 1120 vfs_setpublicfs(NULL, NULL, NULL); 1121 1122 vfs_msync(mp, MNT_WAIT); 1123 async_flag = mp->mnt_flag & MNT_ASYNC; 1124 mp->mnt_flag &= ~MNT_ASYNC; 1125 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1126 if (mp->mnt_syncer != NULL) 1127 vrele(mp->mnt_syncer); 1128 /* 1129 * For forced unmounts, move process cdir/rdir refs on the fs root 1130 * vnode to the covered vnode. For non-forced unmounts we want 1131 * such references to cause an EBUSY error. 1132 */ 1133 if ((flags & MNT_FORCE) && 1134 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1135 if (mp->mnt_vnodecovered != NULL) 1136 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1137 if (fsrootvp == rootvnode) { 1138 vrele(rootvnode); 1139 rootvnode = NULL; 1140 } 1141 vput(fsrootvp); 1142 } 1143 if (((mp->mnt_flag & MNT_RDONLY) || 1144 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1145 (flags & MNT_FORCE)) { 1146 error = VFS_UNMOUNT(mp, flags, td); 1147 } 1148 vn_finished_write(mp); 1149 if (error) { 1150 /* Undo cdir/rdir and rootvnode changes made above. */ 1151 if ((flags & MNT_FORCE) && 1152 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1153 if (mp->mnt_vnodecovered != NULL) 1154 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1155 if (rootvnode == NULL) { 1156 rootvnode = fsrootvp; 1157 vref(rootvnode); 1158 } 1159 vput(fsrootvp); 1160 } 1161 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 1162 (void) vfs_allocate_syncvnode(mp); 1163 MNT_ILOCK(mp); 1164 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1165 mp->mnt_flag |= async_flag; 1166 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1167 if (mp->mnt_kern_flag & MNTK_MWAIT) 1168 wakeup(mp); 1169 MNT_IUNLOCK(mp); 1170 if (coveredvp) 1171 VOP_UNLOCK(coveredvp, 0, td); 1172 return (error); 1173 } 1174 mtx_lock(&mountlist_mtx); 1175 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1176 mtx_unlock(&mountlist_mtx); 1177 if (coveredvp != NULL) { 1178 coveredvp->v_mountedhere = NULL; 1179 vput(coveredvp); 1180 } 1181 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1182 vfs_mount_destroy(mp, td); 1183 return (0); 1184} 1185 1186/* 1187 * --------------------------------------------------------------------- 1188 * Mounting of root filesystem 1189 * 1190 */ 1191 1192struct root_hold_token { 1193 const char *who; 1194 LIST_ENTRY(root_hold_token) list; 1195}; 1196 1197static LIST_HEAD(, root_hold_token) root_holds = 1198 LIST_HEAD_INITIALIZER(&root_holds); 1199 1200struct root_hold_token * 1201root_mount_hold(const char *identifier) 1202{ 1203 struct root_hold_token *h; 1204 1205 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1206 h->who = identifier; 1207 mtx_lock(&mountlist_mtx); 1208 LIST_INSERT_HEAD(&root_holds, h, list); 1209 mtx_unlock(&mountlist_mtx); 1210 return (h); 1211} 1212 1213void 1214root_mount_rel(struct root_hold_token *h) 1215{ 1216 1217 mtx_lock(&mountlist_mtx); 1218 LIST_REMOVE(h, list); 1219 wakeup(&root_holds); 1220 mtx_unlock(&mountlist_mtx); 1221 free(h, M_DEVBUF); 1222} 1223 1224static void 1225root_mount_wait(void) 1226{ 1227 struct root_hold_token *h; 1228 1229 for (;;) { 1230 DROP_GIANT(); 1231 g_waitidle(); 1232 PICKUP_GIANT(); 1233 mtx_lock(&mountlist_mtx); 1234 if (LIST_EMPTY(&root_holds)) { 1235 mtx_unlock(&mountlist_mtx); 1236 break; 1237 } 1238 printf("Root mount waiting for:"); 1239 LIST_FOREACH(h, &root_holds, list) 1240 printf(" %s", h->who); 1241 printf("\n"); 1242 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1243 hz); 1244 } 1245} 1246 1247static void 1248set_rootvnode(struct thread *td) 1249{ 1250 struct proc *p; 1251 1252 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1253 panic("Cannot find root vnode"); 1254 1255 p = td->td_proc; 1256 FILEDESC_LOCK(p->p_fd); 1257 1258 if (p->p_fd->fd_cdir != NULL) 1259 vrele(p->p_fd->fd_cdir); 1260 p->p_fd->fd_cdir = rootvnode; 1261 VREF(rootvnode); 1262 1263 if (p->p_fd->fd_rdir != NULL) 1264 vrele(p->p_fd->fd_rdir); 1265 p->p_fd->fd_rdir = rootvnode; 1266 VREF(rootvnode); 1267 1268 FILEDESC_UNLOCK(p->p_fd); 1269 1270 VOP_UNLOCK(rootvnode, 0, td); 1271} 1272 1273/* 1274 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1275 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1276 */ 1277 1278static void 1279devfs_first(void) 1280{ 1281 struct thread *td = curthread; 1282 struct vfsoptlist *opts; 1283 struct vfsconf *vfsp; 1284 struct mount *mp = NULL; 1285 int error; 1286 1287 vfsp = vfs_byname("devfs"); 1288 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1289 if (vfsp == NULL) 1290 return; 1291 1292 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1293 1294 error = VFS_MOUNT(mp, td); 1295 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1296 if (error) 1297 return; 1298 1299 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1300 TAILQ_INIT(opts); 1301 mp->mnt_opt = opts; 1302 1303 mtx_lock(&mountlist_mtx); 1304 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1305 mtx_unlock(&mountlist_mtx); 1306 1307 set_rootvnode(td); 1308 1309 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1310 if (error) 1311 printf("kern_symlink /dev -> / returns %d\n", error); 1312} 1313 1314/* 1315 * Surgically move our devfs to be mounted on /dev. 1316 */ 1317 1318static void 1319devfs_fixup(struct thread *td) 1320{ 1321 struct nameidata nd; 1322 int error; 1323 struct vnode *vp, *dvp; 1324 struct mount *mp; 1325 1326 /* Remove our devfs mount from the mountlist and purge the cache */ 1327 mtx_lock(&mountlist_mtx); 1328 mp = TAILQ_FIRST(&mountlist); 1329 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1330 mtx_unlock(&mountlist_mtx); 1331 cache_purgevfs(mp); 1332 1333 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1334 VI_LOCK(dvp); 1335 dvp->v_iflag &= ~VI_MOUNT; 1336 dvp->v_mountedhere = NULL; 1337 VI_UNLOCK(dvp); 1338 1339 /* Set up the real rootvnode, and purge the cache */ 1340 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1341 set_rootvnode(td); 1342 cache_purgevfs(rootvnode->v_mount); 1343 1344 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1345 error = namei(&nd); 1346 if (error) { 1347 printf("Lookup of /dev for devfs, error: %d\n", error); 1348 return; 1349 } 1350 NDFREE(&nd, NDF_ONLY_PNBUF); 1351 vp = nd.ni_vp; 1352 if (vp->v_type != VDIR) { 1353 vput(vp); 1354 } 1355 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1356 if (error) { 1357 vput(vp); 1358 } 1359 cache_purge(vp); 1360 mp->mnt_vnodecovered = vp; 1361 vp->v_mountedhere = mp; 1362 mtx_lock(&mountlist_mtx); 1363 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1364 mtx_unlock(&mountlist_mtx); 1365 VOP_UNLOCK(vp, 0, td); 1366 vput(dvp); 1367 vfs_unbusy(mp, td); 1368 1369 /* Unlink the no longer needed /dev/dev -> / symlink */ 1370 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1371} 1372 1373/* 1374 * Report errors during filesystem mounting. 1375 */ 1376void 1377vfs_mount_error(struct mount *mp, const char *fmt, ...) 1378{ 1379 struct vfsoptlist *moptlist = mp->mnt_optnew; 1380 va_list ap; 1381 int error, len; 1382 char *errmsg; 1383 1384 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1385 if (error || errmsg == NULL || len <= 0) 1386 return; 1387 1388 va_start(ap, fmt); 1389 vsnprintf(errmsg, (size_t)len, fmt, ap); 1390 va_end(ap); 1391} 1392 1393/* 1394 * Find and mount the root filesystem 1395 */ 1396void 1397vfs_mountroot(void) 1398{ 1399 char *cp; 1400 int error, i, asked = 0; 1401 1402 root_mount_wait(); 1403 1404 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1405 NULL, NULL, mount_init, mount_fini, 1406 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1407 devfs_first(); 1408 1409 /* 1410 * We are booted with instructions to prompt for the root filesystem. 1411 */ 1412 if (boothowto & RB_ASKNAME) { 1413 if (!vfs_mountroot_ask()) 1414 return; 1415 asked = 1; 1416 } 1417 1418 /* 1419 * The root filesystem information is compiled in, and we are 1420 * booted with instructions to use it. 1421 */ 1422 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1423 if (!vfs_mountroot_try(ctrootdevname)) 1424 return; 1425 ctrootdevname = NULL; 1426 } 1427 1428 /* 1429 * We've been given the generic "use CDROM as root" flag. This is 1430 * necessary because one media may be used in many different 1431 * devices, so we need to search for them. 1432 */ 1433 if (boothowto & RB_CDROM) { 1434 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1435 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1436 return; 1437 } 1438 } 1439 1440 /* 1441 * Try to use the value read by the loader from /etc/fstab, or 1442 * supplied via some other means. This is the preferred 1443 * mechanism. 1444 */ 1445 cp = getenv("vfs.root.mountfrom"); 1446 if (cp != NULL) { 1447 error = vfs_mountroot_try(cp); 1448 freeenv(cp); 1449 if (!error) 1450 return; 1451 } 1452 1453 /* 1454 * Try values that may have been computed by code during boot 1455 */ 1456 if (!vfs_mountroot_try(rootdevnames[0])) 1457 return; 1458 if (!vfs_mountroot_try(rootdevnames[1])) 1459 return; 1460 1461 /* 1462 * If we (still) have a compiled-in default, try it. 1463 */ 1464 if (ctrootdevname != NULL) 1465 if (!vfs_mountroot_try(ctrootdevname)) 1466 return; 1467 /* 1468 * Everything so far has failed, prompt on the console if we haven't 1469 * already tried that. 1470 */ 1471 if (!asked) 1472 if (!vfs_mountroot_ask()) 1473 return; 1474 1475 panic("Root mount failed, startup aborted."); 1476} 1477 1478/* 1479 * Mount (mountfrom) as the root filesystem. 1480 */ 1481static int 1482vfs_mountroot_try(const char *mountfrom) 1483{ 1484 struct mount *mp; 1485 char *vfsname, *path; 1486 time_t timebase; 1487 int error; 1488 char patt[32]; 1489 1490 vfsname = NULL; 1491 path = NULL; 1492 mp = NULL; 1493 error = EINVAL; 1494 1495 if (mountfrom == NULL) 1496 return (error); /* don't complain */ 1497 printf("Trying to mount root from %s\n", mountfrom); 1498 1499 /* parse vfs name and path */ 1500 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1501 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1502 vfsname[0] = path[0] = 0; 1503 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1504 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1505 goto out; 1506 1507 if (path[0] == '\0') 1508 strcpy(path, ROOTNAME); 1509 1510 error = kernel_vmount( 1511 MNT_RDONLY | MNT_ROOTFS, 1512 "fstype", vfsname, 1513 "fspath", "/", 1514 "from", path, 1515 NULL); 1516 if (error == 0) { 1517 /* 1518 * We mount devfs prior to mounting the / FS, so the first 1519 * entry will typically be devfs. 1520 */ 1521 mp = TAILQ_FIRST(&mountlist); 1522 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1523 1524 /* 1525 * Iterate over all currently mounted file systems and use 1526 * the time stamp found to check and/or initialize the RTC. 1527 * Typically devfs has no time stamp and the only other FS 1528 * is the actual / FS. 1529 * Call inittodr() only once and pass it the largest of the 1530 * timestamps we encounter. 1531 */ 1532 timebase = 0; 1533 do { 1534 if (mp->mnt_time > timebase) 1535 timebase = mp->mnt_time; 1536 mp = TAILQ_NEXT(mp, mnt_list); 1537 } while (mp != NULL); 1538 inittodr(timebase); 1539 1540 devfs_fixup(curthread); 1541 } 1542out: 1543 free(path, M_MOUNT); 1544 free(vfsname, M_MOUNT); 1545 return (error); 1546} 1547 1548/* 1549 * --------------------------------------------------------------------- 1550 * Interactive root filesystem selection code. 1551 */ 1552 1553static int 1554vfs_mountroot_ask(void) 1555{ 1556 char name[128]; 1557 1558 for(;;) { 1559 printf("\nManual root filesystem specification:\n"); 1560 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1561#if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1562 printf(" eg. ufs:da0s1a\n"); 1563#else 1564 printf(" eg. ufs:/dev/da0a\n"); 1565#endif 1566 printf(" ? List valid disk boot devices\n"); 1567 printf(" <empty line> Abort manual input\n"); 1568 printf("\nmountroot> "); 1569 gets(name, sizeof(name), 1); 1570 if (name[0] == '\0') 1571 return (1); 1572 if (name[0] == '?') { 1573 printf("\nList of GEOM managed disk devices:\n "); 1574 g_dev_print(); 1575 continue; 1576 } 1577 if (!vfs_mountroot_try(name)) 1578 return (0); 1579 } 1580} 1581 1582/* 1583 * --------------------------------------------------------------------- 1584 * Functions for querying mount options/arguments from filesystems. 1585 */ 1586 1587/* 1588 * Check that no unknown options are given 1589 */ 1590int 1591vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1592{ 1593 struct vfsopt *opt; 1594 const char **t, *p; 1595 1596 1597 TAILQ_FOREACH(opt, opts, link) { 1598 p = opt->name; 1599 if (p[0] == 'n' && p[1] == 'o') 1600 p += 2; 1601 for(t = global_opts; *t != NULL; t++) 1602 if (!strcmp(*t, p)) 1603 break; 1604 if (*t != NULL) 1605 continue; 1606 for(t = legal; *t != NULL; t++) 1607 if (!strcmp(*t, p)) 1608 break; 1609 if (*t != NULL) 1610 continue; 1611 printf("mount option <%s> is unknown\n", p); 1612 return (EINVAL); 1613 } 1614 return (0); 1615} 1616 1617/* 1618 * Get a mount option by its name. 1619 * 1620 * Return 0 if the option was found, ENOENT otherwise. 1621 * If len is non-NULL it will be filled with the length 1622 * of the option. If buf is non-NULL, it will be filled 1623 * with the address of the option. 1624 */ 1625int 1626vfs_getopt(opts, name, buf, len) 1627 struct vfsoptlist *opts; 1628 const char *name; 1629 void **buf; 1630 int *len; 1631{ 1632 struct vfsopt *opt; 1633 1634 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1635 1636 TAILQ_FOREACH(opt, opts, link) { 1637 if (strcmp(name, opt->name) == 0) { 1638 if (len != NULL) 1639 *len = opt->len; 1640 if (buf != NULL) 1641 *buf = opt->value; 1642 return (0); 1643 } 1644 } 1645 return (ENOENT); 1646} 1647 1648static int 1649vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1650{ 1651 struct vfsopt *opt; 1652 int i; 1653 1654 if (opts == NULL) 1655 return (-1); 1656 1657 i = 0; 1658 TAILQ_FOREACH(opt, opts, link) { 1659 if (strcmp(name, opt->name) == 0) 1660 return (i); 1661 ++i; 1662 } 1663 return (-1); 1664} 1665 1666char * 1667vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1668{ 1669 struct vfsopt *opt; 1670 1671 *error = 0; 1672 TAILQ_FOREACH(opt, opts, link) { 1673 if (strcmp(name, opt->name) != 0) 1674 continue; 1675 if (((char *)opt->value)[opt->len - 1] != '\0') { 1676 *error = EINVAL; 1677 return (NULL); 1678 } 1679 return (opt->value); 1680 } 1681 return (NULL); 1682} 1683 1684int 1685vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1686{ 1687 struct vfsopt *opt; 1688 1689 TAILQ_FOREACH(opt, opts, link) { 1690 if (strcmp(name, opt->name) == 0) { 1691 if (w != NULL) 1692 *w |= val; 1693 return (1); 1694 } 1695 } 1696 if (w != NULL) 1697 *w &= ~val; 1698 return (0); 1699} 1700 1701int 1702vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1703{ 1704 va_list ap; 1705 struct vfsopt *opt; 1706 int ret; 1707 1708 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1709 1710 TAILQ_FOREACH(opt, opts, link) { 1711 if (strcmp(name, opt->name) != 0) 1712 continue; 1713 if (((char *)opt->value)[opt->len - 1] != '\0') 1714 return (0); 1715 va_start(ap, fmt); 1716 ret = vsscanf(opt->value, fmt, ap); 1717 va_end(ap); 1718 return (ret); 1719 } 1720 return (0); 1721} 1722 1723/* 1724 * Find and copy a mount option. 1725 * 1726 * The size of the buffer has to be specified 1727 * in len, if it is not the same length as the 1728 * mount option, EINVAL is returned. 1729 * Returns ENOENT if the option is not found. 1730 */ 1731int 1732vfs_copyopt(opts, name, dest, len) 1733 struct vfsoptlist *opts; 1734 const char *name; 1735 void *dest; 1736 int len; 1737{ 1738 struct vfsopt *opt; 1739 1740 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1741 1742 TAILQ_FOREACH(opt, opts, link) { 1743 if (strcmp(name, opt->name) == 0) { 1744 if (len != opt->len) 1745 return (EINVAL); 1746 bcopy(opt->value, dest, opt->len); 1747 return (0); 1748 } 1749 } 1750 return (ENOENT); 1751} 1752 1753/* 1754 * This is a helper function for filesystems to traverse their 1755 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1756 */ 1757 1758struct vnode * 1759__mnt_vnode_next(struct vnode **mvp, struct mount *mp) 1760{ 1761 struct vnode *vp; 1762 1763 mtx_assert(MNT_MTX(mp), MA_OWNED); 1764 1765 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 1766 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 1767 while (vp != NULL && vp->v_type == VMARKER) 1768 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1769 1770 /* Check if we are done */ 1771 if (vp == NULL) { 1772 __mnt_vnode_markerfree(mvp, mp); 1773 return (NULL); 1774 } 1775 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 1776 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 1777 return (vp); 1778} 1779 1780struct vnode * 1781__mnt_vnode_first(struct vnode **mvp, struct mount *mp) 1782{ 1783 struct vnode *vp; 1784 1785 mtx_assert(MNT_MTX(mp), MA_OWNED); 1786 1787 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1788 while (vp != NULL && vp->v_type == VMARKER) 1789 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1790 1791 /* Check if we are done */ 1792 if (vp == NULL) { 1793 *mvp = NULL; 1794 return (NULL); 1795 } 1796 mp->mnt_holdcnt++; 1797 MNT_IUNLOCK(mp); 1798 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 1799 M_VNODE_MARKER, 1800 M_WAITOK | M_ZERO); 1801 MNT_ILOCK(mp); 1802 (*mvp)->v_type = VMARKER; 1803 1804 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1805 while (vp != NULL && vp->v_type == VMARKER) 1806 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1807 1808 /* Check if we are done */ 1809 if (vp == NULL) { 1810 MNT_IUNLOCK(mp); 1811 free(*mvp, M_VNODE_MARKER); 1812 MNT_ILOCK(mp); 1813 *mvp = NULL; 1814 mp->mnt_holdcnt--; 1815 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 1816 wakeup(&mp->mnt_holdcnt); 1817 return (NULL); 1818 } 1819 mp->mnt_markercnt++; 1820 (*mvp)->v_mount = mp; 1821 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 1822 return (vp); 1823} 1824 1825 1826void 1827__mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 1828{ 1829 1830 if (*mvp == NULL) 1831 return; 1832 1833 mtx_assert(MNT_MTX(mp), MA_OWNED); 1834 1835 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 1836 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 1837 MNT_IUNLOCK(mp); 1838 free(*mvp, M_VNODE_MARKER); 1839 MNT_ILOCK(mp); 1840 *mvp = NULL; 1841 1842 mp->mnt_markercnt--; 1843 mp->mnt_holdcnt--; 1844 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 1845 wakeup(&mp->mnt_holdcnt); 1846} 1847 1848 1849int 1850__vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 1851{ 1852 int error; 1853 1854 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 1855 if (sbp != &mp->mnt_stat) 1856 *sbp = mp->mnt_stat; 1857 return (error); 1858} 1859 1860void 1861vfs_mountedfrom(struct mount *mp, const char *from) 1862{ 1863 1864 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1865 strlcpy(mp->mnt_stat.f_mntfromname, from, 1866 sizeof mp->mnt_stat.f_mntfromname); 1867} 1868 1869/* 1870 * --------------------------------------------------------------------- 1871 * This is the api for building mount args and mounting filesystems from 1872 * inside the kernel. 1873 * 1874 * The API works by accumulation of individual args. First error is 1875 * latched. 1876 * 1877 * XXX: should be documented in new manpage kernel_mount(9) 1878 */ 1879 1880/* A memory allocation which must be freed when we are done */ 1881struct mntaarg { 1882 SLIST_ENTRY(mntaarg) next; 1883}; 1884 1885/* The header for the mount arguments */ 1886struct mntarg { 1887 struct iovec *v; 1888 int len; 1889 int error; 1890 SLIST_HEAD(, mntaarg) list; 1891}; 1892 1893/* 1894 * Add a boolean argument. 1895 * 1896 * flag is the boolean value. 1897 * name must start with "no". 1898 */ 1899struct mntarg * 1900mount_argb(struct mntarg *ma, int flag, const char *name) 1901{ 1902 1903 KASSERT(name[0] == 'n' && name[1] == 'o', 1904 ("mount_argb(...,%s): name must start with 'no'", name)); 1905 1906 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1907} 1908 1909/* 1910 * Add an argument printf style 1911 */ 1912struct mntarg * 1913mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1914{ 1915 va_list ap; 1916 struct mntaarg *maa; 1917 struct sbuf *sb; 1918 int len; 1919 1920 if (ma == NULL) { 1921 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1922 SLIST_INIT(&ma->list); 1923 } 1924 if (ma->error) 1925 return (ma); 1926 1927 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1928 M_MOUNT, M_WAITOK); 1929 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1930 ma->v[ma->len].iov_len = strlen(name) + 1; 1931 ma->len++; 1932 1933 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 1934 va_start(ap, fmt); 1935 sbuf_vprintf(sb, fmt, ap); 1936 va_end(ap); 1937 sbuf_finish(sb); 1938 len = sbuf_len(sb) + 1; 1939 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1940 SLIST_INSERT_HEAD(&ma->list, maa, next); 1941 bcopy(sbuf_data(sb), maa + 1, len); 1942 sbuf_delete(sb); 1943 1944 ma->v[ma->len].iov_base = maa + 1; 1945 ma->v[ma->len].iov_len = len; 1946 ma->len++; 1947 1948 return (ma); 1949} 1950 1951/* 1952 * Add an argument which is a userland string. 1953 */ 1954struct mntarg * 1955mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1956{ 1957 struct mntaarg *maa; 1958 char *tbuf; 1959 1960 if (val == NULL) 1961 return (ma); 1962 if (ma == NULL) { 1963 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1964 SLIST_INIT(&ma->list); 1965 } 1966 if (ma->error) 1967 return (ma); 1968 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1969 SLIST_INSERT_HEAD(&ma->list, maa, next); 1970 tbuf = (void *)(maa + 1); 1971 ma->error = copyinstr(val, tbuf, len, NULL); 1972 return (mount_arg(ma, name, tbuf, -1)); 1973} 1974 1975/* 1976 * Plain argument. 1977 * 1978 * If length is -1, use printf. 1979 */ 1980struct mntarg * 1981mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1982{ 1983 1984 if (ma == NULL) { 1985 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1986 SLIST_INIT(&ma->list); 1987 } 1988 if (ma->error) 1989 return (ma); 1990 1991 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1992 M_MOUNT, M_WAITOK); 1993 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1994 ma->v[ma->len].iov_len = strlen(name) + 1; 1995 ma->len++; 1996 1997 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1998 if (len < 0) 1999 ma->v[ma->len].iov_len = strlen(val) + 1; 2000 else 2001 ma->v[ma->len].iov_len = len; 2002 ma->len++; 2003 return (ma); 2004} 2005 2006/* 2007 * Free a mntarg structure 2008 */ 2009static void 2010free_mntarg(struct mntarg *ma) 2011{ 2012 struct mntaarg *maa; 2013 2014 while (!SLIST_EMPTY(&ma->list)) { 2015 maa = SLIST_FIRST(&ma->list); 2016 SLIST_REMOVE_HEAD(&ma->list, next); 2017 free(maa, M_MOUNT); 2018 } 2019 free(ma->v, M_MOUNT); 2020 free(ma, M_MOUNT); 2021} 2022 2023/* 2024 * Mount a filesystem 2025 */ 2026int 2027kernel_mount(struct mntarg *ma, int flags) 2028{ 2029 struct uio auio; 2030 int error; 2031 2032 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2033 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2034 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2035 2036 auio.uio_iov = ma->v; 2037 auio.uio_iovcnt = ma->len; 2038 auio.uio_segflg = UIO_SYSSPACE; 2039 2040 error = ma->error; 2041 if (!error) 2042 error = vfs_donmount(curthread, flags, &auio); 2043 free_mntarg(ma); 2044 return (error); 2045} 2046 2047/* 2048 * A printflike function to mount a filesystem. 2049 */ 2050int 2051kernel_vmount(int flags, ...) 2052{ 2053 struct mntarg *ma = NULL; 2054 va_list ap; 2055 const char *cp; 2056 const void *vp; 2057 int error; 2058 2059 va_start(ap, flags); 2060 for (;;) { 2061 cp = va_arg(ap, const char *); 2062 if (cp == NULL) 2063 break; 2064 vp = va_arg(ap, const void *); 2065 ma = mount_arg(ma, cp, vp, -1); 2066 } 2067 va_end(ap); 2068 2069 error = kernel_mount(ma, flags); 2070 return (error); 2071} 2072