vfs_mount.c revision 139095
187182Salfred/* 287182Salfred * Copyright (c) 1999-2004 Poul-Henning Kamp 387182Salfred * Copyright (c) 1999 Michael Smith 487182Salfred * Copyright (c) 1989, 1993 587182Salfred * The Regents of the University of California. All rights reserved. 687182Salfred * (c) UNIX System Laboratories, Inc. 787182Salfred * All or some portions of this file are derived from material licensed 887182Salfred * to the University of California by American Telephone and Telegraph 987182Salfred * Co. or Unix System Laboratories, Inc. and are reproduced herein with 1087182Salfred * the permission of UNIX System Laboratories, Inc. 1187182Salfred * 1287182Salfred * Redistribution and use in source and binary forms, with or without 1387182Salfred * modification, are permitted provided that the following conditions 1487182Salfred * are met: 1587182Salfred * 1. Redistributions of source code must retain the above copyright 1687182Salfred * notice, this list of conditions and the following disclaimer. 1787182Salfred * 2. Redistributions in binary form must reproduce the above copyright 1887182Salfred * notice, this list of conditions and the following disclaimer in the 1987182Salfred * documentation and/or other materials provided with the distribution. 2087182Salfred * 4. Neither the name of the University nor the names of its contributors 2187182Salfred * may be used to endorse or promote products derived from this software 2287182Salfred * without specific prior written permission. 2387182Salfred * 2487182Salfred * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 2587182Salfred * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2687182Salfred * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2787182Salfred * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 2887182Salfred * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29168203Smaxim * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 3087182Salfred * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3187182Salfred * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3287182Salfred * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33168203Smaxim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3487857Sru * SUCH DAMAGE. 3587182Salfred */ 3687182Salfred 3787182Salfred#include <sys/cdefs.h> 3887182Salfred__FBSDID("$FreeBSD: head/sys/kern/vfs_mount.c 139095 2004-12-20 21:59:25Z phk $"); 3987182Salfred 4087182Salfred#include <sys/param.h> 41176606Sdavidc#include <sys/conf.h> 42176606Sdavidc#include <sys/cons.h> 4387182Salfred#include <sys/jail.h> 44168203Smaxim#include <sys/kernel.h> 45168203Smaxim#include <sys/mac.h> 4687182Salfred#include <sys/malloc.h> 4787182Salfred#include <sys/mount.h> 4887182Salfred#include <sys/mutex.h> 49176606Sdavidc#include <sys/namei.h> 50176606Sdavidc#include <sys/proc.h> 51176606Sdavidc#include <sys/filedesc.h> 5287857Sru#include <sys/reboot.h> 5387857Sru#include <sys/syscallsubr.h> 5487857Sru#include <sys/sysproto.h> 5587182Salfred#include <sys/sx.h> 5687182Salfred#include <sys/sysctl.h> 5787182Salfred#include <sys/sysent.h> 5887182Salfred#include <sys/systm.h> 59168203Smaxim#include <sys/vnode.h> 60168203Smaxim 61168203Smaxim#include <geom/geom.h> 6287857Sru 6387857Sru#include <machine/stdarg.h> 64148271Srodrigc 65168203Smaxim#include "opt_rootdevname.h" 66168203Smaxim#include "opt_ddb.h" 67168203Smaxim#include "opt_mac.h" 6887182Salfred 69148271Srodrigc#ifdef DDB 70168203Smaxim#include <ddb/ddb.h> 71176606Sdavidc#endif 72176606Sdavidc 73168203Smaxim#define ROOTNAME "root_device" 74176606Sdavidc#define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 75176606Sdavidc 76168203Smaximstatic void gets(char *cp); 77168203Smaximstatic int vfs_domount(struct thread *td, const char *fstype, 78176606Sdavidc char *fspath, int fsflags, void *fsdata); 7987182Salfredstatic int vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 80176606Sdavidc const char *fspath, struct thread *td, struct mount **mpp); 8187182Salfredstatic int vfs_mountroot_ask(void); 82147647Shmpstatic int vfs_mountroot_try(const char *mountfrom); 8387182Salfredstatic int vfs_donmount(struct thread *td, int fsflags, 84 struct uio *fsoptions); 85 86static int usermount = 0; 87SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 88 "Unprivileged users may mount and unmount file systems"); 89 90MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 91 92/* List of mounted filesystems. */ 93struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 94 95/* For any iteration/modification of mountlist */ 96struct mtx mountlist_mtx; 97 98TAILQ_HEAD(vfsoptlist, vfsopt); 99struct vfsopt { 100 TAILQ_ENTRY(vfsopt) link; 101 char *name; 102 void *value; 103 int len; 104}; 105 106/* 107 * The vnode of the system's root (/ in the filesystem, without chroot 108 * active.) 109 */ 110struct vnode *rootvnode; 111 112/* 113 * The root filesystem is detailed in the kernel environment variable 114 * vfs.root.mountfrom, which is expected to be in the general format 115 * 116 * <vfsname>:[<path>] 117 * vfsname := the name of a VFS known to the kernel and capable 118 * of being mounted as root 119 * path := disk device name or other data used by the filesystem 120 * to locate its physical store 121 */ 122 123/* 124 * Global opts, taken by all filesystems 125 */ 126static const char *global_opts[] = { 127 "fstype", 128 "fspath", 129 "ro", 130 "suid", 131 "exec", 132 NULL 133}; 134 135/* 136 * The root specifiers we will try if RB_CDROM is specified. 137 */ 138static char *cdrom_rootdevnames[] = { 139 "cd9660:cd0", 140 "cd9660:acd0", 141 NULL 142}; 143 144/* legacy find-root code */ 145char *rootdevnames[2] = {NULL, NULL}; 146#ifndef ROOTDEVNAME 147# define ROOTDEVNAME NULL 148#endif 149const char *ctrootdevname = ROOTDEVNAME; 150 151/* 152 * --------------------------------------------------------------------- 153 * Functions for building and sanitizing the mount options 154 */ 155 156/* Remove one mount option. */ 157static void 158vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 159{ 160 161 TAILQ_REMOVE(opts, opt, link); 162 free(opt->name, M_MOUNT); 163 if (opt->value != NULL) 164 free(opt->value, M_MOUNT); 165#ifdef INVARIANTS 166 else if (opt->len != 0) 167 panic("%s: mount option with NULL value but length != 0", 168 __func__); 169#endif 170 free(opt, M_MOUNT); 171} 172 173/* Release all resources related to the mount options. */ 174static void 175vfs_freeopts(struct vfsoptlist *opts) 176{ 177 struct vfsopt *opt; 178 179 while (!TAILQ_EMPTY(opts)) { 180 opt = TAILQ_FIRST(opts); 181 vfs_freeopt(opts, opt); 182 } 183 free(opts, M_MOUNT); 184} 185 186/* 187 * Check if options are equal (with or without the "no" prefix). 188 */ 189static int 190vfs_equalopts(const char *opt1, const char *opt2) 191{ 192 193 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 194 if (strcmp(opt1, opt2) == 0) 195 return (1); 196 /* "noopt" vs. "opt" */ 197 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 198 return (1); 199 /* "opt" vs. "noopt" */ 200 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 201 return (1); 202 return (0); 203} 204 205/* 206 * If a mount option is specified several times, 207 * (with or without the "no" prefix) only keep 208 * the last occurence of it. 209 */ 210static void 211vfs_sanitizeopts(struct vfsoptlist *opts) 212{ 213 struct vfsopt *opt, *opt2, *tmp; 214 215 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 216 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 217 while (opt2 != NULL) { 218 if (vfs_equalopts(opt->name, opt2->name)) { 219 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 220 vfs_freeopt(opts, opt2); 221 opt2 = tmp; 222 } else { 223 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 224 } 225 } 226 } 227} 228 229/* 230 * Build a linked list of mount options from a struct uio. 231 */ 232static int 233vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 234{ 235 struct vfsoptlist *opts; 236 struct vfsopt *opt; 237 size_t memused; 238 unsigned int i, iovcnt; 239 int error, namelen, optlen; 240 241 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 242 TAILQ_INIT(opts); 243 memused = 0; 244 iovcnt = auio->uio_iovcnt; 245 for (i = 0; i < iovcnt; i += 2) { 246 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 247 namelen = auio->uio_iov[i].iov_len; 248 optlen = auio->uio_iov[i + 1].iov_len; 249 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 250 opt->value = NULL; 251 opt->len = 0; 252 253 /* 254 * Do this early, so jumps to "bad" will free the current 255 * option. 256 */ 257 TAILQ_INSERT_TAIL(opts, opt, link); 258 memused += sizeof(struct vfsopt) + optlen + namelen; 259 260 /* 261 * Avoid consuming too much memory, and attempts to overflow 262 * memused. 263 */ 264 if (memused > VFS_MOUNTARG_SIZE_MAX || 265 optlen > VFS_MOUNTARG_SIZE_MAX || 266 namelen > VFS_MOUNTARG_SIZE_MAX) { 267 error = EINVAL; 268 goto bad; 269 } 270 271 if (auio->uio_segflg == UIO_SYSSPACE) { 272 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 273 } else { 274 error = copyin(auio->uio_iov[i].iov_base, opt->name, 275 namelen); 276 if (error) 277 goto bad; 278 } 279 /* Ensure names are null-terminated strings. */ 280 if (opt->name[namelen - 1] != '\0') { 281 error = EINVAL; 282 goto bad; 283 } 284 if (optlen != 0) { 285 opt->len = optlen; 286 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 287 if (auio->uio_segflg == UIO_SYSSPACE) { 288 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 289 optlen); 290 } else { 291 error = copyin(auio->uio_iov[i + 1].iov_base, 292 opt->value, optlen); 293 if (error) 294 goto bad; 295 } 296 } 297 } 298 vfs_sanitizeopts(opts); 299 *options = opts; 300 return (0); 301bad: 302 vfs_freeopts(opts); 303 return (error); 304} 305 306/* 307 * Merge the old mount options with the new ones passed 308 * in the MNT_UPDATE case. 309 */ 310static void 311vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 312{ 313 struct vfsopt *opt, *opt2, *new; 314 315 TAILQ_FOREACH(opt, opts, link) { 316 /* 317 * Check that this option hasn't been redefined 318 * nor cancelled with a "no" mount option. 319 */ 320 opt2 = TAILQ_FIRST(toopts); 321 while (opt2 != NULL) { 322 if (strcmp(opt2->name, opt->name) == 0) 323 goto next; 324 if (strncmp(opt2->name, "no", 2) == 0 && 325 strcmp(opt2->name + 2, opt->name) == 0) { 326 vfs_freeopt(toopts, opt2); 327 goto next; 328 } 329 opt2 = TAILQ_NEXT(opt2, link); 330 } 331 /* We want this option, duplicate it. */ 332 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 333 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 334 strcpy(new->name, opt->name); 335 if (opt->len != 0) { 336 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 337 bcopy(opt->value, new->value, opt->len); 338 } else { 339 new->value = NULL; 340 } 341 new->len = opt->len; 342 TAILQ_INSERT_TAIL(toopts, new, link); 343next: 344 continue; 345 } 346} 347 348/* 349 * --------------------------------------------------------------------- 350 * Mount a filesystem 351 */ 352int 353nmount(td, uap) 354 struct thread *td; 355 struct nmount_args /* { 356 struct iovec *iovp; 357 unsigned int iovcnt; 358 int flags; 359 } */ *uap; 360{ 361 struct uio *auio; 362 struct iovec *iov; 363 unsigned int i; 364 int error; 365 u_int iovcnt; 366 367 /* Kick out MNT_ROOTFS early as it is legal internally */ 368 if (uap->flags & MNT_ROOTFS) 369 return (EINVAL); 370 371 iovcnt = uap->iovcnt; 372 /* 373 * Check that we have an even number of iovec's 374 * and that we have at least two options. 375 */ 376 if ((iovcnt & 1) || (iovcnt < 4)) 377 return (EINVAL); 378 379 error = copyinuio(uap->iovp, iovcnt, &auio); 380 if (error) 381 return (error); 382 iov = auio->uio_iov; 383 for (i = 0; i < iovcnt; i++) { 384 if (iov->iov_len > MMAXOPTIONLEN) { 385 free(auio, M_IOV); 386 return (EINVAL); 387 } 388 iov++; 389 } 390 error = vfs_donmount(td, uap->flags, auio); 391 free(auio, M_IOV); 392 return (error); 393} 394 395/* 396 * --------------------------------------------------------------------- 397 * Various utility functions 398 */ 399 400/* 401 * Allocate and initialize the mount point struct. 402 */ 403static int 404vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 405 const char *fspath, struct thread *td, struct mount **mpp) 406{ 407 struct mount *mp; 408 409 mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 410 TAILQ_INIT(&mp->mnt_nvnodelist); 411 mp->mnt_nvnodelistsize = 0; 412 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 413 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 414 vfs_busy(mp, LK_NOWAIT, 0, td); 415 mp->mnt_op = vfsp->vfc_vfsops; 416 mp->mnt_vfc = vfsp; 417 vfsp->vfc_refcount++; 418 mp->mnt_stat.f_type = vfsp->vfc_typenum; 419 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 420 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 421 mp->mnt_vnodecovered = vp; 422 mp->mnt_cred = crdup(td->td_ucred); 423 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 424 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 425 mp->mnt_iosize_max = DFLTPHYS; 426#ifdef MAC 427 mac_init_mount(mp); 428 mac_create_mount(td->td_ucred, mp); 429#endif 430 *mpp = mp; 431 return (0); 432} 433 434/* 435 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 436 */ 437void 438vfs_mount_destroy(struct mount *mp, struct thread *td) 439{ 440 441 mp->mnt_vfc->vfc_refcount--; 442 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 443 panic("unmount: dangling vnode"); 444 vfs_unbusy(mp,td); 445 lockdestroy(&mp->mnt_lock); 446 mtx_destroy(&mp->mnt_mtx); 447 if (mp->mnt_kern_flag & MNTK_MWAIT) 448 wakeup(mp); 449#ifdef MAC 450 mac_destroy_mount(mp); 451#endif 452 if (mp->mnt_opt != NULL) 453 vfs_freeopts(mp->mnt_opt); 454 crfree(mp->mnt_cred); 455 free(mp, M_MOUNT); 456} 457 458static int 459vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 460{ 461 struct vfsoptlist *optlist; 462 char *fstype, *fspath; 463 int error, fstypelen, fspathlen; 464 465 error = vfs_buildopts(fsoptions, &optlist); 466 if (error) 467 return (error); 468 469 /* 470 * We need these two options before the others, 471 * and they are mandatory for any filesystem. 472 * Ensure they are NUL terminated as well. 473 */ 474 fstypelen = 0; 475 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 476 if (error || fstype[fstypelen - 1] != '\0') { 477 error = EINVAL; 478 goto bail; 479 } 480 fspathlen = 0; 481 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 482 if (error || fspath[fspathlen - 1] != '\0') { 483 error = EINVAL; 484 goto bail; 485 } 486 487 /* 488 * Be ultra-paranoid about making sure the type and fspath 489 * variables will fit in our mp buffers, including the 490 * terminating NUL. 491 */ 492 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 493 error = ENAMETOOLONG; 494 goto bail; 495 } 496 497 mtx_lock(&Giant); 498 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 499 mtx_unlock(&Giant); 500bail: 501 if (error) 502 vfs_freeopts(optlist); 503 return (error); 504} 505 506/* 507 * --------------------------------------------------------------------- 508 * Old mount API. 509 */ 510#ifndef _SYS_SYSPROTO_H_ 511struct mount_args { 512 char *type; 513 char *path; 514 int flags; 515 caddr_t data; 516}; 517#endif 518/* ARGSUSED */ 519int 520mount(td, uap) 521 struct thread *td; 522 struct mount_args /* { 523 char *type; 524 char *path; 525 int flags; 526 caddr_t data; 527 } */ *uap; 528{ 529 char *fstype; 530 struct vfsconf *vfsp = NULL; 531 struct mntarg *ma = NULL; 532 int error; 533 534 /* Kick out MNT_ROOTFS early as it is legal internally */ 535 uap->flags &= ~MNT_ROOTFS; 536 537 if (uap->data == NULL) 538 return (EINVAL); 539 540 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 541 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 542 if (!error) { 543 mtx_lock(&Giant); /* XXX ? */ 544 vfsp = vfs_byname_kld(fstype, td, &error); 545 mtx_unlock(&Giant); 546 } 547 free(fstype, M_TEMP); 548 if (error) 549 return (error); 550 if (vfsp == NULL) 551 return (ENOENT); 552 if (vfsp->vfc_vfsops->vfs_cmount == NULL) 553 return (EOPNOTSUPP); 554 555 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 556 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 557 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 558 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 559 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 560 561 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 562 return (error); 563} 564 565 566/* 567 * vfs_domount(): actually attempt a filesystem mount. 568 */ 569static int 570vfs_domount( 571 struct thread *td, /* Flags common to all filesystems. */ 572 const char *fstype, /* Filesystem type. */ 573 char *fspath, /* Mount path. */ 574 int fsflags, /* Flags common to all filesystems. */ 575 void *fsdata /* Options local to the filesystem. */ 576 ) 577{ 578 struct vnode *vp; 579 struct mount *mp; 580 struct vfsconf *vfsp; 581 int error, flag = 0, kern_flag = 0; 582 struct vattr va; 583 struct nameidata nd; 584 585 mtx_assert(&Giant, MA_OWNED); 586 587 /* 588 * Be ultra-paranoid about making sure the type and fspath 589 * variables will fit in our mp buffers, including the 590 * terminating NUL. 591 */ 592 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 593 return (ENAMETOOLONG); 594 595 if (jailed(td->td_ucred)) 596 return (EPERM); 597 if (usermount == 0) { 598 if ((error = suser(td)) != 0) 599 return (error); 600 } 601 602 /* 603 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 604 */ 605 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 606 if ((error = suser(td)) != 0) 607 return (error); 608 } 609 /* 610 * Silently enforce MNT_NOSUID and MNT_USER for 611 * unprivileged users. 612 */ 613 if (suser(td) != 0) 614 fsflags |= MNT_NOSUID | MNT_USER; 615 /* 616 * Get vnode to be covered 617 */ 618 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 619 if ((error = namei(&nd)) != 0) 620 return (error); 621 NDFREE(&nd, NDF_ONLY_PNBUF); 622 vp = nd.ni_vp; 623 if (fsflags & MNT_UPDATE) { 624 if ((vp->v_vflag & VV_ROOT) == 0) { 625 vput(vp); 626 return (EINVAL); 627 } 628 mp = vp->v_mount; 629 flag = mp->mnt_flag; 630 kern_flag = mp->mnt_kern_flag; 631 /* 632 * We only allow the filesystem to be reloaded if it 633 * is currently mounted read-only. 634 */ 635 if ((fsflags & MNT_RELOAD) && 636 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 637 vput(vp); 638 return (EOPNOTSUPP); /* Needs translation */ 639 } 640 /* 641 * Only privileged root, or (if MNT_USER is set) the user that 642 * did the original mount is permitted to update it. 643 */ 644 error = vfs_suser(mp, td); 645 if (error) { 646 vput(vp); 647 return (error); 648 } 649 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 650 vput(vp); 651 return (EBUSY); 652 } 653 VI_LOCK(vp); 654 if ((vp->v_iflag & VI_MOUNT) != 0 || 655 vp->v_mountedhere != NULL) { 656 VI_UNLOCK(vp); 657 vfs_unbusy(mp, td); 658 vput(vp); 659 return (EBUSY); 660 } 661 vp->v_iflag |= VI_MOUNT; 662 VI_UNLOCK(vp); 663 mp->mnt_flag |= fsflags & 664 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 665 VOP_UNLOCK(vp, 0, td); 666 mp->mnt_optnew = fsdata; 667 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 668 } else { 669 /* 670 * If the user is not root, ensure that they own the directory 671 * onto which we are attempting to mount. 672 */ 673 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 674 if (error) { 675 vput(vp); 676 return (error); 677 } 678 if (va.va_uid != td->td_ucred->cr_uid) { 679 if ((error = suser(td)) != 0) { 680 vput(vp); 681 return (error); 682 } 683 } 684 error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0); 685 if (error != 0) { 686 vput(vp); 687 return (error); 688 } 689 if (vp->v_type != VDIR) { 690 vput(vp); 691 return (ENOTDIR); 692 } 693 vfsp = vfs_byname_kld(fstype, td, &error); 694 if (vfsp == NULL) { 695 vput(vp); 696 return (error); 697 } 698 VI_LOCK(vp); 699 if ((vp->v_iflag & VI_MOUNT) != 0 || 700 vp->v_mountedhere != NULL) { 701 VI_UNLOCK(vp); 702 vput(vp); 703 return (EBUSY); 704 } 705 vp->v_iflag |= VI_MOUNT; 706 VI_UNLOCK(vp); 707 708 /* 709 * Allocate and initialize the filesystem. 710 */ 711 error = vfs_mount_alloc(vp, vfsp, fspath, td, &mp); 712 if (error) { 713 vput(vp); 714 return (error); 715 } 716 VOP_UNLOCK(vp, 0, td); 717 718 /* XXXMAC: pass to vfs_mount_alloc? */ 719 mp->mnt_optnew = fsdata; 720 } 721 722 /* 723 * Set the mount level flags. 724 */ 725 if (fsflags & MNT_RDONLY) 726 mp->mnt_flag |= MNT_RDONLY; 727 mp->mnt_flag &=~ MNT_UPDATEMASK; 728 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS); 729 /* 730 * Mount the filesystem. 731 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 732 * get. No freeing of cn_pnbuf. 733 */ 734 error = VFS_MOUNT(mp, td); 735 if (!error) { 736 if (mp->mnt_opt != NULL) 737 vfs_freeopts(mp->mnt_opt); 738 mp->mnt_opt = mp->mnt_optnew; 739 VFS_STATFS(mp, &mp->mnt_stat, td); 740 } 741 /* 742 * Prevent external consumers of mount options from reading 743 * mnt_optnew. 744 */ 745 mp->mnt_optnew = NULL; 746 if (mp->mnt_flag & MNT_UPDATE) { 747 mp->mnt_flag &= 748 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 749 if (error) { 750 mp->mnt_flag = flag; 751 mp->mnt_kern_flag = kern_flag; 752 } 753 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 754 if (mp->mnt_syncer == NULL) 755 error = vfs_allocate_syncvnode(mp); 756 } else { 757 if (mp->mnt_syncer != NULL) 758 vrele(mp->mnt_syncer); 759 mp->mnt_syncer = NULL; 760 } 761 vfs_unbusy(mp, td); 762 VI_LOCK(vp); 763 vp->v_iflag &= ~VI_MOUNT; 764 VI_UNLOCK(vp); 765 vrele(vp); 766 return (error); 767 } 768 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 769 /* 770 * Put the new filesystem on the mount list after root. 771 */ 772 cache_purge(vp); 773 if (!error) { 774 struct vnode *newdp; 775 776 VI_LOCK(vp); 777 vp->v_iflag &= ~VI_MOUNT; 778 VI_UNLOCK(vp); 779 vp->v_mountedhere = mp; 780 mtx_lock(&mountlist_mtx); 781 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 782 mtx_unlock(&mountlist_mtx); 783 vfs_event_signal(NULL, VQ_MOUNT, 0); 784 if (VFS_ROOT(mp, &newdp, td)) 785 panic("mount: lost mount"); 786 mountcheckdirs(vp, newdp); 787 vput(newdp); 788 VOP_UNLOCK(vp, 0, td); 789 if ((mp->mnt_flag & MNT_RDONLY) == 0) 790 error = vfs_allocate_syncvnode(mp); 791 vfs_unbusy(mp, td); 792 if (error || (error = VFS_START(mp, 0, td)) != 0) 793 vrele(vp); 794 } else { 795 VI_LOCK(vp); 796 vp->v_iflag &= ~VI_MOUNT; 797 VI_UNLOCK(vp); 798 vfs_mount_destroy(mp, td); 799 vput(vp); 800 } 801 return (error); 802} 803 804/* 805 * --------------------------------------------------------------------- 806 * Unmount a filesystem. 807 * 808 * Note: unmount takes a path to the vnode mounted on as argument, 809 * not special file (as before). 810 */ 811#ifndef _SYS_SYSPROTO_H_ 812struct unmount_args { 813 char *path; 814 int flags; 815}; 816#endif 817/* ARGSUSED */ 818int 819unmount(td, uap) 820 struct thread *td; 821 register struct unmount_args /* { 822 char *path; 823 int flags; 824 } */ *uap; 825{ 826 struct mount *mp; 827 char *pathbuf; 828 int error, id0, id1; 829 830 if (jailed(td->td_ucred)) 831 return (EPERM); 832 if (usermount == 0) { 833 if ((error = suser(td)) != 0) 834 return (error); 835 } 836 837 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 838 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 839 if (error) { 840 free(pathbuf, M_TEMP); 841 return (error); 842 } 843 if (uap->flags & MNT_BYFSID) { 844 /* Decode the filesystem ID. */ 845 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 846 free(pathbuf, M_TEMP); 847 return (EINVAL); 848 } 849 850 mtx_lock(&mountlist_mtx); 851 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 852 if (mp->mnt_stat.f_fsid.val[0] == id0 && 853 mp->mnt_stat.f_fsid.val[1] == id1) 854 break; 855 } 856 mtx_unlock(&mountlist_mtx); 857 } else { 858 mtx_lock(&mountlist_mtx); 859 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 860 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 861 break; 862 } 863 mtx_unlock(&mountlist_mtx); 864 } 865 free(pathbuf, M_TEMP); 866 if (mp == NULL) { 867 /* 868 * Previously we returned ENOENT for a nonexistent path and 869 * EINVAL for a non-mountpoint. We cannot tell these apart 870 * now, so in the !MNT_BYFSID case return the more likely 871 * EINVAL for compatibility. 872 */ 873 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 874 } 875 876 /* 877 * Only privileged root, or (if MNT_USER is set) the user that did the 878 * original mount is permitted to unmount this filesystem. 879 */ 880 error = vfs_suser(mp, td); 881 if (error) 882 return (error); 883 884 /* 885 * Don't allow unmounting the root filesystem. 886 */ 887 if (mp->mnt_flag & MNT_ROOTFS) 888 return (EINVAL); 889 mtx_lock(&Giant); 890 error = dounmount(mp, uap->flags, td); 891 mtx_unlock(&Giant); 892 return (error); 893} 894 895/* 896 * Do the actual filesystem unmount. 897 */ 898int 899dounmount(mp, flags, td) 900 struct mount *mp; 901 int flags; 902 struct thread *td; 903{ 904 struct vnode *coveredvp, *fsrootvp; 905 int error; 906 int async_flag; 907 908 mtx_assert(&Giant, MA_OWNED); 909 910 mtx_lock(&mountlist_mtx); 911 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 912 mtx_unlock(&mountlist_mtx); 913 return (EBUSY); 914 } 915 mp->mnt_kern_flag |= MNTK_UNMOUNT; 916 /* Allow filesystems to detect that a forced unmount is in progress. */ 917 if (flags & MNT_FORCE) 918 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 919 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 920 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), &mountlist_mtx, td); 921 if (error) { 922 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 923 if (mp->mnt_kern_flag & MNTK_MWAIT) 924 wakeup(mp); 925 return (error); 926 } 927 vn_start_write(NULL, &mp, V_WAIT); 928 929 if (mp->mnt_flag & MNT_EXPUBLIC) 930 vfs_setpublicfs(NULL, NULL, NULL); 931 932 vfs_msync(mp, MNT_WAIT); 933 async_flag = mp->mnt_flag & MNT_ASYNC; 934 mp->mnt_flag &= ~MNT_ASYNC; 935 cache_purgevfs(mp); /* remove cache entries for this file sys */ 936 if (mp->mnt_syncer != NULL) 937 vrele(mp->mnt_syncer); 938 /* 939 * For forced unmounts, move process cdir/rdir refs on the fs root 940 * vnode to the covered vnode. For non-forced unmounts we want 941 * such references to cause an EBUSY error. 942 */ 943 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 944 if (mp->mnt_vnodecovered != NULL) 945 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 946 if (fsrootvp == rootvnode) { 947 vrele(rootvnode); 948 rootvnode = NULL; 949 } 950 vput(fsrootvp); 951 } 952 if (((mp->mnt_flag & MNT_RDONLY) || 953 (error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) == 0) || 954 (flags & MNT_FORCE)) { 955 error = VFS_UNMOUNT(mp, flags, td); 956 } 957 vn_finished_write(mp); 958 if (error) { 959 /* Undo cdir/rdir and rootvnode changes made above. */ 960 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 961 if (mp->mnt_vnodecovered != NULL) 962 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 963 if (rootvnode == NULL) { 964 rootvnode = fsrootvp; 965 vref(rootvnode); 966 } 967 vput(fsrootvp); 968 } 969 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 970 (void) vfs_allocate_syncvnode(mp); 971 mtx_lock(&mountlist_mtx); 972 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 973 mp->mnt_flag |= async_flag; 974 lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, 975 &mountlist_mtx, td); 976 if (mp->mnt_kern_flag & MNTK_MWAIT) 977 wakeup(mp); 978 return (error); 979 } 980 mtx_lock(&mountlist_mtx); 981 TAILQ_REMOVE(&mountlist, mp, mnt_list); 982 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 983 coveredvp->v_mountedhere = NULL; 984 mtx_unlock(&mountlist_mtx); 985 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 986 vfs_mount_destroy(mp, td); 987 if (coveredvp != NULL) 988 vrele(coveredvp); 989 return (0); 990} 991 992/* 993 * --------------------------------------------------------------------- 994 * Mounting of root filesystem 995 * 996 */ 997 998static void 999set_rootvnode(struct thread *td) 1000{ 1001 struct proc *p; 1002 1003 if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode, td)) 1004 panic("Cannot find root vnode"); 1005 1006 p = td->td_proc; 1007 FILEDESC_LOCK(p->p_fd); 1008 1009 if (p->p_fd->fd_cdir != NULL) 1010 vrele(p->p_fd->fd_cdir); 1011 p->p_fd->fd_cdir = rootvnode; 1012 VREF(rootvnode); 1013 1014 if (p->p_fd->fd_rdir != NULL) 1015 vrele(p->p_fd->fd_rdir); 1016 p->p_fd->fd_rdir = rootvnode; 1017 VREF(rootvnode); 1018 1019 FILEDESC_UNLOCK(p->p_fd); 1020 1021 VOP_UNLOCK(rootvnode, 0, td); 1022} 1023 1024/* 1025 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1026 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1027 */ 1028 1029static struct mount * 1030devfs_first(void) 1031{ 1032 struct thread *td = curthread; 1033 struct vfsconf *vfsp; 1034 struct mount *mp = NULL; 1035 int error; 1036 1037 vfsp = vfs_byname("devfs"); 1038 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1039 if (vfsp == NULL) 1040 return(NULL); 1041 1042 error = vfs_mount_alloc(NULLVP, vfsp, "/dev", td, &mp); 1043 KASSERT(error == 0, ("vfs_mount_alloc failed %d", error)); 1044 if (error) 1045 return (NULL); 1046 1047 error = VFS_MOUNT(mp, curthread); 1048 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1049 if (error) 1050 return (NULL); 1051 1052 VFS_START(mp, 0, td); 1053 1054 mtx_lock(&mountlist_mtx); 1055 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1056 mtx_unlock(&mountlist_mtx); 1057 1058 set_rootvnode(td); 1059 1060 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1061 if (error) 1062 printf("kern_symlink /dev -> / returns %d\n", error); 1063 1064 return (mp); 1065} 1066 1067/* 1068 * Surgically move our devfs to be mounted on /dev. 1069 */ 1070 1071static void 1072devfs_fixup(struct thread *td) 1073{ 1074 struct nameidata nd; 1075 int error; 1076 struct vnode *vp, *dvp; 1077 struct mount *mp; 1078 1079 /* Remove our devfs mount from the mountlist and purge the cache */ 1080 mtx_lock(&mountlist_mtx); 1081 mp = TAILQ_FIRST(&mountlist); 1082 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1083 mtx_unlock(&mountlist_mtx); 1084 cache_purgevfs(mp); 1085 1086 VFS_ROOT(mp, &dvp, td); 1087 VI_LOCK(dvp); 1088 dvp->v_iflag &= ~VI_MOUNT; 1089 dvp->v_mountedhere = NULL; 1090 VI_UNLOCK(dvp); 1091 1092 /* Set up the real rootvnode, and purge the cache */ 1093 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1094 set_rootvnode(td); 1095 cache_purgevfs(rootvnode->v_mount); 1096 1097 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1098 error = namei(&nd); 1099 if (error) { 1100 printf("Lookup /dev -> %d\n", error); 1101 return; 1102 } 1103 NDFREE(&nd, NDF_ONLY_PNBUF); 1104 vp = nd.ni_vp; 1105 if (vp->v_type != VDIR) { 1106 vput(vp); 1107 } 1108 error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0); 1109 if (error) { 1110 vput(vp); 1111 } 1112 cache_purge(vp); 1113 mp->mnt_vnodecovered = vp; 1114 vp->v_mountedhere = mp; 1115 mtx_lock(&mountlist_mtx); 1116 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1117 mtx_unlock(&mountlist_mtx); 1118 VOP_UNLOCK(vp, 0, td); 1119 vfs_unbusy(mp, td); 1120 VREF(vp); 1121 vput(vp); 1122 vput(dvp); 1123 1124 /* Unlink the no longer needed /dev/dev -> / symlink */ 1125 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1126} 1127 1128/* 1129 * Find and mount the root filesystem 1130 */ 1131void 1132vfs_mountroot(void) 1133{ 1134 char *cp; 1135 int error, i, asked = 0; 1136 struct mount *mp; 1137 1138 /* 1139 * Wait for GEOM to settle down 1140 */ 1141 DROP_GIANT(); 1142 g_waitidle(); 1143 PICKUP_GIANT(); 1144 1145 mp = devfs_first(); 1146 1147 /* 1148 * We are booted with instructions to prompt for the root filesystem. 1149 */ 1150 if (boothowto & RB_ASKNAME) { 1151 if (!vfs_mountroot_ask()) 1152 return; 1153 asked = 1; 1154 } 1155 1156 /* 1157 * The root filesystem information is compiled in, and we are 1158 * booted with instructions to use it. 1159 */ 1160 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1161 if (!vfs_mountroot_try(ctrootdevname)) 1162 return; 1163 ctrootdevname = NULL; 1164 } 1165 1166 /* 1167 * We've been given the generic "use CDROM as root" flag. This is 1168 * necessary because one media may be used in many different 1169 * devices, so we need to search for them. 1170 */ 1171 if (boothowto & RB_CDROM) { 1172 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1173 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1174 return; 1175 } 1176 } 1177 1178 /* 1179 * Try to use the value read by the loader from /etc/fstab, or 1180 * supplied via some other means. This is the preferred 1181 * mechanism. 1182 */ 1183 cp = getenv("vfs.root.mountfrom"); 1184 if (cp != NULL) { 1185 error = vfs_mountroot_try(cp); 1186 freeenv(cp); 1187 if (!error) 1188 return; 1189 } 1190 1191 /* 1192 * Try values that may have been computed by code during boot 1193 */ 1194 if (!vfs_mountroot_try(rootdevnames[0])) 1195 return; 1196 if (!vfs_mountroot_try(rootdevnames[1])) 1197 return; 1198 1199 /* 1200 * If we (still) have a compiled-in default, try it. 1201 */ 1202 if (ctrootdevname != NULL) 1203 if (!vfs_mountroot_try(ctrootdevname)) 1204 return; 1205 /* 1206 * Everything so far has failed, prompt on the console if we haven't 1207 * already tried that. 1208 */ 1209 if (!asked) 1210 if (!vfs_mountroot_ask()) 1211 return; 1212 1213 panic("Root mount failed, startup aborted."); 1214} 1215 1216/* 1217 * Mount (mountfrom) as the root filesystem. 1218 */ 1219static int 1220vfs_mountroot_try(const char *mountfrom) 1221{ 1222 struct mount *mp; 1223 char *vfsname, *path; 1224 int error; 1225 char patt[32]; 1226 int s; 1227 1228 vfsname = NULL; 1229 path = NULL; 1230 mp = NULL; 1231 error = EINVAL; 1232 1233 if (mountfrom == NULL) 1234 return (error); /* don't complain */ 1235 1236 s = splcam(); /* Overkill, but annoying without it */ 1237 printf("Trying to mount root from %s\n", mountfrom); 1238 splx(s); 1239 1240 /* parse vfs name and path */ 1241 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1242 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1243 vfsname[0] = path[0] = 0; 1244 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1245 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1246 return (error); 1247 1248 if (path[0] == '\0') 1249 strcpy(path, ROOTNAME); 1250 1251 error = kernel_vmount( 1252 MNT_RDONLY | MNT_ROOTFS, 1253 "fstype", vfsname, 1254 "fspath", "/", 1255 "from", path, 1256 NULL); 1257 if (error == 0) { 1258 mp = TAILQ_FIRST(&mountlist); 1259 1260 /* sanity check system clock against root fs timestamp */ 1261 inittodr(mp->mnt_time); 1262 vfs_unbusy(mp, curthread); 1263 error = VFS_START(mp, 0, curthread); 1264 1265 devfs_fixup(curthread); 1266 } 1267 return (error); 1268} 1269 1270/* 1271 * --------------------------------------------------------------------- 1272 * Interactive root filesystem selection code. 1273 */ 1274 1275static int 1276vfs_mountroot_ask(void) 1277{ 1278 char name[128]; 1279 1280 for(;;) { 1281 printf("\nManual root filesystem specification:\n"); 1282 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1283#if defined(__i386__) || defined(__ia64__) 1284 printf(" eg. ufs:da0s1a\n"); 1285#else 1286 printf(" eg. ufs:/dev/da0a\n"); 1287#endif 1288 printf(" ? List valid disk boot devices\n"); 1289 printf(" <empty line> Abort manual input\n"); 1290 printf("\nmountroot> "); 1291 gets(name); 1292 if (name[0] == '\0') 1293 return (1); 1294 if (name[0] == '?') { 1295 printf("\nList of GEOM managed disk devices:\n "); 1296 g_dev_print(); 1297 continue; 1298 } 1299 if (!vfs_mountroot_try(name)) 1300 return (0); 1301 } 1302} 1303 1304/* 1305 * Local helper function for vfs_mountroot_ask. 1306 */ 1307static void 1308gets(char *cp) 1309{ 1310 char *lp; 1311 int c; 1312 1313 lp = cp; 1314 for (;;) { 1315 printf("%c", c = cngetc() & 0177); 1316 switch (c) { 1317 case -1: 1318 case '\n': 1319 case '\r': 1320 *lp++ = '\0'; 1321 return; 1322 case '\b': 1323 case '\177': 1324 if (lp > cp) { 1325 printf(" \b"); 1326 lp--; 1327 } 1328 continue; 1329 case '#': 1330 lp--; 1331 if (lp < cp) 1332 lp = cp; 1333 continue; 1334 case '@': 1335 case 'u' & 037: 1336 lp = cp; 1337 printf("%c", '\n'); 1338 continue; 1339 default: 1340 *lp++ = c; 1341 } 1342 } 1343} 1344 1345/* 1346 * --------------------------------------------------------------------- 1347 * Functions for querying mount options/arguments from filesystems. 1348 */ 1349 1350/* 1351 * Check that no unknown options are given 1352 */ 1353int 1354vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1355{ 1356 struct vfsopt *opt; 1357 const char **t, *p; 1358 1359 1360 TAILQ_FOREACH(opt, opts, link) { 1361 p = opt->name; 1362 if (p[0] == 'n' && p[1] == 'o') 1363 p += 2; 1364 for(t = global_opts; *t != NULL; t++) 1365 if (!strcmp(*t, p)) 1366 break; 1367 if (*t != NULL) 1368 continue; 1369 for(t = legal; *t != NULL; t++) 1370 if (!strcmp(*t, p)) 1371 break; 1372 if (*t != NULL) 1373 continue; 1374 printf("mount option <%s> is unknown\n", p); 1375 return (EINVAL); 1376 } 1377 return (0); 1378} 1379 1380/* 1381 * Get a mount option by its name. 1382 * 1383 * Return 0 if the option was found, ENOENT otherwise. 1384 * If len is non-NULL it will be filled with the length 1385 * of the option. If buf is non-NULL, it will be filled 1386 * with the address of the option. 1387 */ 1388int 1389vfs_getopt(opts, name, buf, len) 1390 struct vfsoptlist *opts; 1391 const char *name; 1392 void **buf; 1393 int *len; 1394{ 1395 struct vfsopt *opt; 1396 1397 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1398 1399 TAILQ_FOREACH(opt, opts, link) { 1400 if (strcmp(name, opt->name) == 0) { 1401 if (len != NULL) 1402 *len = opt->len; 1403 if (buf != NULL) 1404 *buf = opt->value; 1405 return (0); 1406 } 1407 } 1408 return (ENOENT); 1409} 1410 1411char * 1412vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1413{ 1414 struct vfsopt *opt; 1415 1416 *error = 0; 1417 TAILQ_FOREACH(opt, opts, link) { 1418 if (strcmp(name, opt->name) != 0) 1419 continue; 1420 if (((char *)opt->value)[opt->len - 1] != '\0') { 1421 *error = EINVAL; 1422 return (NULL); 1423 } 1424 return (opt->value); 1425 } 1426 return (NULL); 1427} 1428 1429int 1430vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1431{ 1432 struct vfsopt *opt; 1433 1434 TAILQ_FOREACH(opt, opts, link) { 1435 if (strcmp(name, opt->name) == 0) { 1436 if (w != NULL) 1437 *w |= val; 1438 return (1); 1439 } 1440 } 1441 if (w != NULL) 1442 *w &= ~val; 1443 return (0); 1444} 1445 1446int 1447vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1448{ 1449 va_list ap; 1450 struct vfsopt *opt; 1451 int ret; 1452 1453 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1454 1455 TAILQ_FOREACH(opt, opts, link) { 1456 if (strcmp(name, opt->name) != 0) 1457 continue; 1458 if (((char *)opt->value)[opt->len - 1] != '\0') 1459 return (0); 1460 va_start(ap, fmt); 1461 ret = vsscanf(opt->value, fmt, ap); 1462 va_end(ap); 1463 return (ret); 1464 } 1465 return (0); 1466} 1467 1468/* 1469 * Find and copy a mount option. 1470 * 1471 * The size of the buffer has to be specified 1472 * in len, if it is not the same length as the 1473 * mount option, EINVAL is returned. 1474 * Returns ENOENT if the option is not found. 1475 */ 1476int 1477vfs_copyopt(opts, name, dest, len) 1478 struct vfsoptlist *opts; 1479 const char *name; 1480 void *dest; 1481 int len; 1482{ 1483 struct vfsopt *opt; 1484 1485 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1486 1487 TAILQ_FOREACH(opt, opts, link) { 1488 if (strcmp(name, opt->name) == 0) { 1489 if (len != opt->len) 1490 return (EINVAL); 1491 bcopy(opt->value, dest, opt->len); 1492 return (0); 1493 } 1494 } 1495 return (ENOENT); 1496} 1497 1498/* 1499 * This is a helper function for filesystems to traverse their 1500 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1501 */ 1502 1503struct vnode * 1504__mnt_vnode_next(struct vnode **nvp, struct mount *mp) 1505{ 1506 struct vnode *vp; 1507 1508 mtx_assert(&mp->mnt_mtx, MA_OWNED); 1509 1510 vp = *nvp; 1511 /* Check if we are done */ 1512 if (vp == NULL) 1513 return (NULL); 1514 /* If our next vnode is no longer ours, start over */ 1515 if (vp->v_mount != mp) 1516 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1517 /* Save pointer to next vnode in list */ 1518 if (vp != NULL) 1519 *nvp = TAILQ_NEXT(vp, v_nmntvnodes); 1520 else 1521 *nvp = NULL; 1522 return (vp); 1523} 1524 1525int 1526__vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 1527{ 1528 int error; 1529 1530 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 1531 if (sbp != &mp->mnt_stat) 1532 *sbp = mp->mnt_stat; 1533 return (error); 1534} 1535 1536void 1537vfs_mountedfrom(struct mount *mp, const char *from) 1538{ 1539 1540 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1541 strlcpy(mp->mnt_stat.f_mntfromname, from, 1542 sizeof mp->mnt_stat.f_mntfromname); 1543} 1544 1545/* 1546 * --------------------------------------------------------------------- 1547 * This is the api for building mount args and mounting filesystems from 1548 * inside the kernel. 1549 * 1550 * The API works by accumulation of individual args. First error is 1551 * latched. 1552 * 1553 * XXX: should be documented in new manpage kernel_mount(9) 1554 */ 1555 1556/* A memory allocation which must be freed when we are done */ 1557struct mntaarg { 1558 SLIST_ENTRY(mntaarg) next; 1559}; 1560 1561/* The header for the mount arguments */ 1562struct mntarg { 1563 struct iovec *v; 1564 int len; 1565 int error; 1566 SLIST_HEAD(, mntaarg) list; 1567}; 1568 1569/* 1570 * Add a boolean argument. 1571 * 1572 * flag is the boolean value. 1573 * name must start with "no". 1574 */ 1575struct mntarg * 1576mount_argb(struct mntarg *ma, int flag, const char *name) 1577{ 1578 1579 KASSERT(name[0] == 'n' && name[1] == 'o', 1580 ("mount_argb(...,%s): name must start with 'no'", name)); 1581 1582 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1583} 1584 1585/* 1586 * Add an argument printf style 1587 */ 1588struct mntarg * 1589mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1590{ 1591 va_list ap; 1592 struct mntaarg *maa; 1593 struct sbuf *sb; 1594 int len; 1595 1596 if (ma == NULL) { 1597 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1598 SLIST_INIT(&ma->list); 1599 } 1600 if (ma->error) 1601 return (ma); 1602 1603 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1604 M_MOUNT, M_WAITOK); 1605 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1606 ma->v[ma->len].iov_len = strlen(name) + 1; 1607 ma->len++; 1608 1609 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 1610 va_start(ap, fmt); 1611 sbuf_vprintf(sb, fmt, ap); 1612 va_end(ap); 1613 sbuf_finish(sb); 1614 len = sbuf_len(sb) + 1; 1615 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1616 SLIST_INSERT_HEAD(&ma->list, maa, next); 1617 bcopy(sbuf_data(sb), maa + 1, len); 1618 sbuf_delete(sb); 1619 1620 ma->v[ma->len].iov_base = maa + 1; 1621 ma->v[ma->len].iov_len = len; 1622 ma->len++; 1623 1624 return (ma); 1625} 1626 1627/* 1628 * Add an argument which is a userland string. 1629 */ 1630struct mntarg * 1631mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1632{ 1633 struct mntaarg *maa; 1634 char *tbuf; 1635 1636 if (val == NULL) 1637 return (ma); 1638 if (ma == NULL) { 1639 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1640 SLIST_INIT(&ma->list); 1641 } 1642 if (ma->error) 1643 return (ma); 1644 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1645 SLIST_INSERT_HEAD(&ma->list, maa, next); 1646 tbuf = (void *)(maa + 1); 1647 ma->error = copyinstr(val, tbuf, len, NULL); 1648 return (mount_arg(ma, name, tbuf, -1)); 1649} 1650 1651/* 1652 * Plain argument. 1653 * 1654 * If length is -1, use printf. 1655 */ 1656struct mntarg * 1657mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1658{ 1659 1660 if (ma == NULL) { 1661 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1662 SLIST_INIT(&ma->list); 1663 } 1664 if (ma->error) 1665 return (ma); 1666 1667 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1668 M_MOUNT, M_WAITOK); 1669 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1670 ma->v[ma->len].iov_len = strlen(name) + 1; 1671 ma->len++; 1672 1673 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1674 if (len < 0) 1675 ma->v[ma->len].iov_len = strlen(val) + 1; 1676 else 1677 ma->v[ma->len].iov_len = len; 1678 ma->len++; 1679 return (ma); 1680} 1681 1682/* 1683 * Free a mntarg structure 1684 */ 1685void 1686free_mntarg(struct mntarg *ma) 1687{ 1688 struct mntaarg *maa; 1689 1690 while (!SLIST_EMPTY(&ma->list)) { 1691 maa = SLIST_FIRST(&ma->list); 1692 SLIST_REMOVE_HEAD(&ma->list, next); 1693 free(maa, M_MOUNT); 1694 } 1695 free(ma->v, M_MOUNT); 1696 free(ma, M_MOUNT); 1697} 1698 1699/* 1700 * Mount a filesystem 1701 */ 1702int 1703kernel_mount(struct mntarg *ma, int flags) 1704{ 1705 struct uio auio; 1706 int error; 1707 1708 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 1709 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 1710 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 1711 1712 auio.uio_iov = ma->v; 1713 auio.uio_iovcnt = ma->len; 1714 auio.uio_segflg = UIO_SYSSPACE; 1715 1716 error = ma->error; 1717 if (!error) 1718 error = vfs_donmount(curthread, flags, &auio); 1719 free_mntarg(ma); 1720 return (error); 1721} 1722 1723/* 1724 * A printflike function to mount a filesystem. 1725 */ 1726int 1727kernel_vmount(int flags, ...) 1728{ 1729 struct mntarg *ma = NULL; 1730 va_list ap; 1731 const char *cp; 1732 const void *vp; 1733 int error; 1734 1735 va_start(ap, flags); 1736 for (;;) { 1737 cp = va_arg(ap, const char *); 1738 if (cp == NULL) 1739 break; 1740 vp = va_arg(ap, const void *); 1741 ma = mount_arg(ma, cp, vp, -1); 1742 } 1743 va_end(ap); 1744 1745 error = kernel_mount(ma, flags); 1746 return (error); 1747} 1748