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