vfs_mount.c revision 138444
1/* 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1989, 1993 4 * The Regents of the University of California. All rights reserved. 5 * (c) UNIX System Laboratories, Inc. 6 * All or some portions of this file are derived from material licensed 7 * to the University of California by American Telephone and Telegraph 8 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 9 * the permission of UNIX System Laboratories, Inc. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * Copyright (c) 1999 Michael Smith 36 * All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 48 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 50 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 51 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 52 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 53 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 54 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 55 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 56 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 57 * SUCH DAMAGE. 58 */ 59 60#include <sys/cdefs.h> 61__FBSDID("$FreeBSD: head/sys/kern/vfs_mount.c 138444 2004-12-06 12:36:17Z phk $"); 62 63#include <sys/param.h> 64#include <sys/conf.h> 65#include <sys/cons.h> 66#include <sys/jail.h> 67#include <sys/kernel.h> 68#include <sys/mac.h> 69#include <sys/malloc.h> 70#include <sys/mount.h> 71#include <sys/mutex.h> 72#include <sys/namei.h> 73#include <sys/proc.h> 74#include <sys/filedesc.h> 75#include <sys/reboot.h> 76#include <sys/sysproto.h> 77#include <sys/sx.h> 78#include <sys/sysctl.h> 79#include <sys/sysent.h> 80#include <sys/systm.h> 81#include <sys/vnode.h> 82 83#include <geom/geom.h> 84 85#include <machine/stdarg.h> 86 87#include "opt_rootdevname.h" 88#include "opt_ddb.h" 89#include "opt_mac.h" 90 91#ifdef DDB 92#include <ddb/ddb.h> 93#endif 94 95#define ROOTNAME "root_device" 96#define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 97 98static void checkdirs(struct vnode *olddp, struct vnode *newdp); 99static struct cdev *getdiskbyname(char *_name); 100static void gets(char *cp); 101static int vfs_domount(struct thread *td, const char *fstype, 102 char *fspath, int fsflags, void *fsdata, int compat); 103static int vfs_mount_alloc(struct vnode *dvp, struct vfsconf *vfsp, 104 const char *fspath, struct thread *td, struct mount **mpp); 105static int vfs_mountroot_ask(void); 106static int vfs_mountroot_try(const char *mountfrom); 107static int vfs_donmount(struct thread *td, int fsflags, 108 struct uio *fsoptions); 109 110static int usermount = 0; 111SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 112 "Unprivileged users may mount and unmount file systems"); 113 114MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 115 116/* List of mounted filesystems. */ 117struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 118 119/* For any iteration/modification of mountlist */ 120struct mtx mountlist_mtx; 121 122TAILQ_HEAD(vfsoptlist, vfsopt); 123struct vfsopt { 124 TAILQ_ENTRY(vfsopt) link; 125 char *name; 126 void *value; 127 int len; 128}; 129 130/* 131 * The vnode of the system's root (/ in the filesystem, without chroot 132 * active.) 133 */ 134struct vnode *rootvnode; 135 136/* 137 * The root filesystem is detailed in the kernel environment variable 138 * vfs.root.mountfrom, which is expected to be in the general format 139 * 140 * <vfsname>:[<path>] 141 * vfsname := the name of a VFS known to the kernel and capable 142 * of being mounted as root 143 * path := disk device name or other data used by the filesystem 144 * to locate its physical store 145 */ 146 147/* 148 * The root specifiers we will try if RB_CDROM is specified. 149 */ 150static char *cdrom_rootdevnames[] = { 151 "cd9660:cd0", 152 "cd9660:acd0", 153 NULL 154}; 155 156/* legacy find-root code */ 157char *rootdevnames[2] = {NULL, NULL}; 158struct cdev *rootdev = NULL; 159#ifdef ROOTDEVNAME 160const char *ctrootdevname = ROOTDEVNAME; 161#else 162const char *ctrootdevname = NULL; 163#endif 164 165/* 166 * Has to be dynamic as the value of rootdev can change; however, it can't 167 * change after the root is mounted, so a user process can't access this 168 * sysctl until after the value is unchangeable. 169 */ 170static int 171sysctl_rootdev(SYSCTL_HANDLER_ARGS) 172{ 173 int error; 174 175 /* _RD prevents this from happening. */ 176 KASSERT(req->newptr == NULL, ("Attempt to change root device name")); 177 178 if (rootdev != NULL) 179 error = sysctl_handle_string(oidp, rootdev->si_name, 0, req); 180 else 181 error = sysctl_handle_string(oidp, "", 0, req); 182 183 return (error); 184} 185 186SYSCTL_PROC(_kern, OID_AUTO, rootdev, CTLTYPE_STRING | CTLFLAG_RD, 187 0, 0, sysctl_rootdev, "A", "Root file system device"); 188 189/* Remove one mount option. */ 190static void 191vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 192{ 193 194 TAILQ_REMOVE(opts, opt, link); 195 free(opt->name, M_MOUNT); 196 if (opt->value != NULL) 197 free(opt->value, M_MOUNT); 198#ifdef INVARIANTS 199 else if (opt->len != 0) 200 panic("%s: mount option with NULL value but length != 0", 201 __func__); 202#endif 203 free(opt, M_MOUNT); 204} 205 206/* Release all resources related to the mount options. */ 207static void 208vfs_freeopts(struct vfsoptlist *opts) 209{ 210 struct vfsopt *opt; 211 212 while (!TAILQ_EMPTY(opts)) { 213 opt = TAILQ_FIRST(opts); 214 vfs_freeopt(opts, opt); 215 } 216 free(opts, M_MOUNT); 217} 218 219/* 220 * Check if options are equal (with or without the "no" prefix). 221 */ 222static int 223vfs_equalopts(const char *opt1, const char *opt2) 224{ 225 226 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 227 if (strcmp(opt1, opt2) == 0) 228 return (1); 229 /* "noopt" vs. "opt" */ 230 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 231 return (1); 232 /* "opt" vs. "noopt" */ 233 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 234 return (1); 235 return (0); 236} 237 238/* 239 * If a mount option is specified several times, 240 * (with or without the "no" prefix) only keep 241 * the last occurence of it. 242 */ 243static void 244vfs_sanitizeopts(struct vfsoptlist *opts) 245{ 246 struct vfsopt *opt, *opt2, *tmp; 247 248 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 249 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 250 while (opt2 != NULL) { 251 if (vfs_equalopts(opt->name, opt2->name)) { 252 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 253 vfs_freeopt(opts, opt2); 254 opt2 = tmp; 255 } else { 256 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 257 } 258 } 259 } 260} 261 262/* 263 * Build a linked list of mount options from a struct uio. 264 */ 265static int 266vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 267{ 268 struct vfsoptlist *opts; 269 struct vfsopt *opt; 270 size_t memused; 271 unsigned int i, iovcnt; 272 int error, namelen, optlen; 273 274 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 275 TAILQ_INIT(opts); 276 memused = 0; 277 iovcnt = auio->uio_iovcnt; 278 for (i = 0; i < iovcnt; i += 2) { 279 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 280 namelen = auio->uio_iov[i].iov_len; 281 optlen = auio->uio_iov[i + 1].iov_len; 282 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 283 opt->value = NULL; 284 opt->len = 0; 285 286 /* 287 * Do this early, so jumps to "bad" will free the current 288 * option. 289 */ 290 TAILQ_INSERT_TAIL(opts, opt, link); 291 memused += sizeof(struct vfsopt) + optlen + namelen; 292 293 /* 294 * Avoid consuming too much memory, and attempts to overflow 295 * memused. 296 */ 297 if (memused > VFS_MOUNTARG_SIZE_MAX || 298 optlen > VFS_MOUNTARG_SIZE_MAX || 299 namelen > VFS_MOUNTARG_SIZE_MAX) { 300 error = EINVAL; 301 goto bad; 302 } 303 304 if (auio->uio_segflg == UIO_SYSSPACE) { 305 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 306 } else { 307 error = copyin(auio->uio_iov[i].iov_base, opt->name, 308 namelen); 309 if (error) 310 goto bad; 311 } 312 /* Ensure names are null-terminated strings. */ 313 if (opt->name[namelen - 1] != '\0') { 314 error = EINVAL; 315 goto bad; 316 } 317 if (optlen != 0) { 318 opt->len = optlen; 319 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 320 if (auio->uio_segflg == UIO_SYSSPACE) { 321 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 322 optlen); 323 } else { 324 error = copyin(auio->uio_iov[i + 1].iov_base, 325 opt->value, optlen); 326 if (error) 327 goto bad; 328 } 329 } 330 } 331 vfs_sanitizeopts(opts); 332 *options = opts; 333 return (0); 334bad: 335 vfs_freeopts(opts); 336 return (error); 337} 338 339/* 340 * Merge the old mount options with the new ones passed 341 * in the MNT_UPDATE case. 342 */ 343static void 344vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 345{ 346 struct vfsopt *opt, *opt2, *new; 347 348 TAILQ_FOREACH(opt, opts, link) { 349 /* 350 * Check that this option hasn't been redefined 351 * nor cancelled with a "no" mount option. 352 */ 353 opt2 = TAILQ_FIRST(toopts); 354 while (opt2 != NULL) { 355 if (strcmp(opt2->name, opt->name) == 0) 356 goto next; 357 if (strncmp(opt2->name, "no", 2) == 0 && 358 strcmp(opt2->name + 2, opt->name) == 0) { 359 vfs_freeopt(toopts, opt2); 360 goto next; 361 } 362 opt2 = TAILQ_NEXT(opt2, link); 363 } 364 /* We want this option, duplicate it. */ 365 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 366 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 367 strcpy(new->name, opt->name); 368 if (opt->len != 0) { 369 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 370 bcopy(opt->value, new->value, opt->len); 371 } else { 372 new->value = NULL; 373 } 374 new->len = opt->len; 375 TAILQ_INSERT_TAIL(toopts, new, link); 376next: 377 continue; 378 } 379} 380 381/* 382 * New mount API. 383 */ 384int 385nmount(td, uap) 386 struct thread *td; 387 struct nmount_args /* { 388 struct iovec *iovp; 389 unsigned int iovcnt; 390 int flags; 391 } */ *uap; 392{ 393 struct uio *auio; 394 struct iovec *iov; 395 unsigned int i; 396 int error; 397 u_int iovcnt; 398 399 /* Kick out MNT_ROOTFS early as it is legal internally */ 400 if (uap->flags & MNT_ROOTFS) 401 return (EINVAL); 402 403 iovcnt = uap->iovcnt; 404 /* 405 * Check that we have an even number of iovec's 406 * and that we have at least two options. 407 */ 408 if ((iovcnt & 1) || (iovcnt < 4)) 409 return (EINVAL); 410 411 error = copyinuio(uap->iovp, iovcnt, &auio); 412 if (error) 413 return (error); 414 iov = auio->uio_iov; 415 for (i = 0; i < iovcnt; i++) { 416 if (iov->iov_len > MMAXOPTIONLEN) { 417 free(auio, M_IOV); 418 return (EINVAL); 419 } 420 iov++; 421 } 422 error = vfs_donmount(td, uap->flags, auio); 423 free(auio, M_IOV); 424 return (error); 425} 426 427struct mntarg { 428 struct iovec *v; 429 int len; 430}; 431 432struct mntarg * 433mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 434{ 435 436 if (ma == NULL) 437 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 438 439 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 440 M_MOUNT, M_WAITOK); 441 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 442 ma->v[ma->len].iov_len = strlen(name) + 1; 443 ma->len++; 444 445 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 446 if (len < 0) 447 ma->v[ma->len].iov_len = strlen(val) + 1; 448 else 449 ma->v[ma->len].iov_len = len; 450 ma->len++; 451 return (ma); 452} 453 454int 455kernel_mount(struct mntarg *ma, int flags) 456{ 457 struct uio auio; 458 int error; 459 460 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 461 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 462 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 463 464 auio.uio_iov = ma->v; 465 auio.uio_iovcnt = ma->len; 466 auio.uio_segflg = UIO_SYSSPACE; 467 468 error = vfs_donmount(curthread, flags, &auio); 469 free(ma->v, M_MOUNT); 470 free(ma, M_MOUNT); 471 return (error); 472} 473 474int 475kernel_vmount(int flags, ...) 476{ 477 struct mntarg *ma = NULL; 478 va_list ap; 479 const char *cp; 480 const void *vp; 481 int error; 482 483 va_start(ap, flags); 484 for (;;) { 485 cp = va_arg(ap, const char *); 486 if (cp == NULL) 487 break; 488 vp = va_arg(ap, const void *); 489 ma = mount_arg(ma, cp, vp, -1); 490 } 491 va_end(ap); 492 493 error = kernel_mount(ma, flags); 494 return (error); 495} 496 497/* 498 * Allocate and initialize the mount point struct. 499 */ 500static int 501vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 502 const char *fspath, struct thread *td, struct mount **mpp) 503{ 504 struct mount *mp; 505 506 mp = malloc(sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 507 TAILQ_INIT(&mp->mnt_nvnodelist); 508 mp->mnt_nvnodelistsize = 0; 509 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 510 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 511 vfs_busy(mp, LK_NOWAIT, 0, td); 512 mp->mnt_op = vfsp->vfc_vfsops; 513 mp->mnt_vfc = vfsp; 514 vfsp->vfc_refcount++; 515 mp->mnt_stat.f_type = vfsp->vfc_typenum; 516 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 517 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 518 mp->mnt_vnodecovered = vp; 519 mp->mnt_cred = crdup(td->td_ucred); 520 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 521 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 522 mp->mnt_iosize_max = DFLTPHYS; 523#ifdef MAC 524 mac_init_mount(mp); 525 mac_create_mount(td->td_ucred, mp); 526#endif 527 *mpp = mp; 528 return (0); 529} 530 531/* 532 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 533 */ 534void 535vfs_mount_destroy(struct mount *mp, struct thread *td) 536{ 537 538 mp->mnt_vfc->vfc_refcount--; 539 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) 540 panic("unmount: dangling vnode"); 541 vfs_unbusy(mp,td); 542 lockdestroy(&mp->mnt_lock); 543 mtx_destroy(&mp->mnt_mtx); 544 if (mp->mnt_kern_flag & MNTK_MWAIT) 545 wakeup(mp); 546#ifdef MAC 547 mac_destroy_mount(mp); 548#endif 549 if (mp->mnt_opt != NULL) 550 vfs_freeopts(mp->mnt_opt); 551 crfree(mp->mnt_cred); 552 free(mp, M_MOUNT); 553} 554 555static int 556vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 557{ 558 struct vfsoptlist *optlist; 559 char *fstype, *fspath; 560 int error, fstypelen, fspathlen; 561 562 error = vfs_buildopts(fsoptions, &optlist); 563 if (error) 564 return (error); 565 566 /* 567 * We need these two options before the others, 568 * and they are mandatory for any filesystem. 569 * Ensure they are NUL terminated as well. 570 */ 571 fstypelen = 0; 572 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 573 if (error || fstype[fstypelen - 1] != '\0') { 574 error = EINVAL; 575 goto bail; 576 } 577 fspathlen = 0; 578 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 579 if (error || fspath[fspathlen - 1] != '\0') { 580 error = EINVAL; 581 goto bail; 582 } 583 584 /* 585 * Be ultra-paranoid about making sure the type and fspath 586 * variables will fit in our mp buffers, including the 587 * terminating NUL. 588 */ 589 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 590 error = ENAMETOOLONG; 591 goto bail; 592 } 593 594 mtx_lock(&Giant); 595 error = vfs_domount(td, fstype, fspath, fsflags, optlist, 0); 596 mtx_unlock(&Giant); 597bail: 598 if (error) 599 vfs_freeopts(optlist); 600 return (error); 601} 602 603/* 604 * Old mount API. 605 */ 606#ifndef _SYS_SYSPROTO_H_ 607struct mount_args { 608 char *type; 609 char *path; 610 int flags; 611 caddr_t data; 612}; 613#endif 614/* ARGSUSED */ 615int 616mount(td, uap) 617 struct thread *td; 618 struct mount_args /* { 619 char *type; 620 char *path; 621 int flags; 622 caddr_t data; 623 } */ *uap; 624{ 625 char *fstype; 626 char *fspath; 627 struct vfsconf *vfsp; 628 int error; 629 630 /* Kick out MNT_ROOTFS early as it is legal internally */ 631 if (uap->flags & MNT_ROOTFS) 632 return (EINVAL); 633 634 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 635 fspath = malloc(MNAMELEN, M_TEMP, M_WAITOK); 636 637 /* 638 * vfs_mount() actually takes a kernel string for `type' and 639 * `path' now, so extract them. 640 */ 641 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 642 if (error == 0) 643 error = copyinstr(uap->path, fspath, MNAMELEN, NULL); 644 if (error == 0) { 645 mtx_lock(&Giant); 646 vfsp = vfs_byname_kld(fstype, td, &error); 647 if (vfsp != NULL) { 648 if (vfsp->vfc_vfsops->vfs_cmount != NULL) { 649 error = vfsp->vfc_vfsops->vfs_cmount( 650 fspath, uap->data, uap->flags, td); 651 } else { 652 error = vfs_domount(td, fstype, fspath, 653 uap->flags, uap->data, 1); 654 } 655 } 656 mtx_unlock(&Giant); 657 } 658 free(fstype, M_TEMP); 659 free(fspath, M_TEMP); 660 return (error); 661} 662 663/* 664 * vfs_domount(): actually attempt a filesystem mount. 665 */ 666static int 667vfs_domount( 668 struct thread *td, /* Flags common to all filesystems. */ 669 const char *fstype, /* Filesystem type. */ 670 char *fspath, /* Mount path. */ 671 int fsflags, /* Flags common to all filesystems. */ 672 void *fsdata, /* Options local to the filesystem. */ 673 int compat /* Invocation from compat syscall. */ 674 ) 675{ 676 struct vnode *vp; 677 struct mount *mp; 678 struct vfsconf *vfsp; 679 int error, flag = 0, kern_flag = 0; 680 struct vattr va; 681 struct nameidata nd; 682 683 mtx_assert(&Giant, MA_OWNED); 684 685 /* 686 * Be ultra-paranoid about making sure the type and fspath 687 * variables will fit in our mp buffers, including the 688 * terminating NUL. 689 */ 690 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 691 return (ENAMETOOLONG); 692 693 if (jailed(td->td_ucred)) 694 return (EPERM); 695 if (usermount == 0) { 696 if ((error = suser(td)) != 0) 697 return (error); 698 } 699 700 /* 701 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 702 */ 703 if (fsflags & (MNT_EXPORTED | MNT_SUIDDIR)) { 704 if ((error = suser(td)) != 0) 705 return (error); 706 } 707 /* 708 * Silently enforce MNT_NOSUID and MNT_USER for 709 * unprivileged users. 710 */ 711 if (suser(td) != 0) 712 fsflags |= MNT_NOSUID | MNT_USER; 713 /* 714 * Get vnode to be covered 715 */ 716 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspath, td); 717 if ((error = namei(&nd)) != 0) 718 return (error); 719 NDFREE(&nd, NDF_ONLY_PNBUF); 720 vp = nd.ni_vp; 721 if (fsflags & MNT_UPDATE) { 722 if ((vp->v_vflag & VV_ROOT) == 0) { 723 vput(vp); 724 return (EINVAL); 725 } 726 mp = vp->v_mount; 727 flag = mp->mnt_flag; 728 kern_flag = mp->mnt_kern_flag; 729 /* 730 * We only allow the filesystem to be reloaded if it 731 * is currently mounted read-only. 732 */ 733 if ((fsflags & MNT_RELOAD) && 734 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 735 vput(vp); 736 return (EOPNOTSUPP); /* Needs translation */ 737 } 738 /* 739 * Only privileged root, or (if MNT_USER is set) the user that 740 * did the original mount is permitted to update it. 741 */ 742 error = vfs_suser(mp, td); 743 if (error) { 744 vput(vp); 745 return (error); 746 } 747 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 748 vput(vp); 749 return (EBUSY); 750 } 751 VI_LOCK(vp); 752 if ((vp->v_iflag & VI_MOUNT) != 0 || 753 vp->v_mountedhere != NULL) { 754 VI_UNLOCK(vp); 755 vfs_unbusy(mp, td); 756 vput(vp); 757 return (EBUSY); 758 } 759 vp->v_iflag |= VI_MOUNT; 760 VI_UNLOCK(vp); 761 mp->mnt_flag |= fsflags & 762 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT); 763 VOP_UNLOCK(vp, 0, td); 764 if (compat == 0) { 765 mp->mnt_optnew = fsdata; 766 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 767 } 768 } else { 769 /* 770 * If the user is not root, ensure that they own the directory 771 * onto which we are attempting to mount. 772 */ 773 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 774 if (error) { 775 vput(vp); 776 return (error); 777 } 778 if (va.va_uid != td->td_ucred->cr_uid) { 779 if ((error = suser(td)) != 0) { 780 vput(vp); 781 return (error); 782 } 783 } 784 if ((error = vinvalbuf(vp, V_SAVE, td->td_ucred, td, 0, 0)) != 0) { 785 vput(vp); 786 return (error); 787 } 788 if (vp->v_type != VDIR) { 789 vput(vp); 790 return (ENOTDIR); 791 } 792 vfsp = vfs_byname_kld(fstype, td, &error); 793 if (vfsp == NULL) { 794 vput(vp); 795 return (error); 796 } 797 VI_LOCK(vp); 798 if ((vp->v_iflag & VI_MOUNT) != 0 || 799 vp->v_mountedhere != NULL) { 800 VI_UNLOCK(vp); 801 vput(vp); 802 return (EBUSY); 803 } 804 vp->v_iflag |= VI_MOUNT; 805 VI_UNLOCK(vp); 806 807 /* 808 * Allocate and initialize the filesystem. 809 */ 810 error = vfs_mount_alloc(vp, vfsp, fspath, td, &mp); 811 if (error) { 812 vput(vp); 813 return (error); 814 } 815 VOP_UNLOCK(vp, 0, td); 816 817 /* XXXMAC: pass to vfs_mount_alloc? */ 818 if (compat == 0) 819 mp->mnt_optnew = fsdata; 820 } 821 /* 822 * Check if the fs implements the type VFS_[O]MOUNT() 823 * function we are looking for. 824 */ 825 if ((compat && (mp->mnt_op->vfs_omount == NULL)) || 826 (!compat && (mp->mnt_op->vfs_mount == NULL))) { 827 printf("%s doesn't support the %s mount syscall\n", 828 mp->mnt_vfc->vfc_name, compat ? "old" : "new"); 829 VI_LOCK(vp); 830 vp->v_iflag &= ~VI_MOUNT; 831 VI_UNLOCK(vp); 832 if (mp->mnt_flag & MNT_UPDATE) 833 vfs_unbusy(mp, td); 834 else 835 vfs_mount_destroy(mp, td); 836 vrele(vp); 837 return (EOPNOTSUPP); 838 } 839 840 /* 841 * Set the mount level flags. 842 */ 843 if (fsflags & MNT_RDONLY) 844 mp->mnt_flag |= MNT_RDONLY; 845 else if (mp->mnt_flag & MNT_RDONLY) 846 mp->mnt_kern_flag |= MNTK_WANTRDWR; 847 mp->mnt_flag &=~ MNT_UPDATEMASK; 848 mp->mnt_flag |= fsflags & (MNT_UPDATEMASK | MNT_FORCE); 849 /* 850 * Mount the filesystem. 851 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 852 * get. No freeing of cn_pnbuf. 853 */ 854 if (compat) 855 error = VFS_OMOUNT(mp, fspath, fsdata, td); 856 else 857 error = VFS_MOUNT(mp, td); 858 if (!error) { 859 if (mp->mnt_opt != NULL) 860 vfs_freeopts(mp->mnt_opt); 861 mp->mnt_opt = mp->mnt_optnew; 862 } 863 /* 864 * Prevent external consumers of mount options from reading 865 * mnt_optnew. 866 */ 867 mp->mnt_optnew = NULL; 868 if (mp->mnt_flag & MNT_UPDATE) { 869 if (mp->mnt_kern_flag & MNTK_WANTRDWR) 870 mp->mnt_flag &= ~MNT_RDONLY; 871 mp->mnt_flag &= 872 ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | MNT_SNAPSHOT); 873 mp->mnt_kern_flag &= ~MNTK_WANTRDWR; 874 if (error) { 875 mp->mnt_flag = flag; 876 mp->mnt_kern_flag = kern_flag; 877 } 878 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 879 if (mp->mnt_syncer == NULL) 880 error = vfs_allocate_syncvnode(mp); 881 } else { 882 if (mp->mnt_syncer != NULL) 883 vrele(mp->mnt_syncer); 884 mp->mnt_syncer = NULL; 885 } 886 vfs_unbusy(mp, td); 887 VI_LOCK(vp); 888 vp->v_iflag &= ~VI_MOUNT; 889 VI_UNLOCK(vp); 890 vrele(vp); 891 return (error); 892 } 893 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 894 /* 895 * Put the new filesystem on the mount list after root. 896 */ 897 cache_purge(vp); 898 if (!error) { 899 struct vnode *newdp; 900 901 VI_LOCK(vp); 902 vp->v_iflag &= ~VI_MOUNT; 903 VI_UNLOCK(vp); 904 vp->v_mountedhere = mp; 905 mtx_lock(&mountlist_mtx); 906 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 907 mtx_unlock(&mountlist_mtx); 908 vfs_event_signal(NULL, VQ_MOUNT, 0); 909 if (VFS_ROOT(mp, &newdp, td)) 910 panic("mount: lost mount"); 911 checkdirs(vp, newdp); 912 vput(newdp); 913 VOP_UNLOCK(vp, 0, td); 914 if ((mp->mnt_flag & MNT_RDONLY) == 0) 915 error = vfs_allocate_syncvnode(mp); 916 vfs_unbusy(mp, td); 917 if (error || (error = VFS_START(mp, 0, td)) != 0) 918 vrele(vp); 919 } else { 920 VI_LOCK(vp); 921 vp->v_iflag &= ~VI_MOUNT; 922 VI_UNLOCK(vp); 923 vfs_mount_destroy(mp, td); 924 vput(vp); 925 } 926 return (error); 927} 928 929/* 930 * Scan all active processes to see if any of them have a current 931 * or root directory of `olddp'. If so, replace them with the new 932 * mount point. 933 */ 934static void 935checkdirs(olddp, newdp) 936 struct vnode *olddp, *newdp; 937{ 938 struct filedesc *fdp; 939 struct proc *p; 940 int nrele; 941 942 if (vrefcnt(olddp) == 1) 943 return; 944 sx_slock(&allproc_lock); 945 LIST_FOREACH(p, &allproc, p_list) { 946 mtx_lock(&fdesc_mtx); 947 fdp = p->p_fd; 948 if (fdp == NULL) { 949 mtx_unlock(&fdesc_mtx); 950 continue; 951 } 952 nrele = 0; 953 FILEDESC_LOCK_FAST(fdp); 954 if (fdp->fd_cdir == olddp) { 955 vref(newdp); 956 fdp->fd_cdir = newdp; 957 nrele++; 958 } 959 if (fdp->fd_rdir == olddp) { 960 vref(newdp); 961 fdp->fd_rdir = newdp; 962 nrele++; 963 } 964 FILEDESC_UNLOCK_FAST(fdp); 965 mtx_unlock(&fdesc_mtx); 966 while (nrele--) 967 vrele(olddp); 968 } 969 sx_sunlock(&allproc_lock); 970 if (rootvnode == olddp) { 971 vrele(rootvnode); 972 vref(newdp); 973 rootvnode = newdp; 974 } 975} 976 977/* 978 * Unmount a filesystem. 979 * 980 * Note: unmount takes a path to the vnode mounted on as argument, 981 * not special file (as before). 982 */ 983#ifndef _SYS_SYSPROTO_H_ 984struct unmount_args { 985 char *path; 986 int flags; 987}; 988#endif 989/* ARGSUSED */ 990int 991unmount(td, uap) 992 struct thread *td; 993 register struct unmount_args /* { 994 char *path; 995 int flags; 996 } */ *uap; 997{ 998 struct mount *mp; 999 char *pathbuf; 1000 int error, id0, id1; 1001 1002 if (jailed(td->td_ucred)) 1003 return (EPERM); 1004 if (usermount == 0) { 1005 if ((error = suser(td)) != 0) 1006 return (error); 1007 } 1008 1009 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1010 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1011 if (error) { 1012 free(pathbuf, M_TEMP); 1013 return (error); 1014 } 1015 if (uap->flags & MNT_BYFSID) { 1016 /* Decode the filesystem ID. */ 1017 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1018 free(pathbuf, M_TEMP); 1019 return (EINVAL); 1020 } 1021 1022 mtx_lock(&mountlist_mtx); 1023 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1024 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1025 mp->mnt_stat.f_fsid.val[1] == id1) 1026 break; 1027 } 1028 mtx_unlock(&mountlist_mtx); 1029 } else { 1030 mtx_lock(&mountlist_mtx); 1031 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1032 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1033 break; 1034 } 1035 mtx_unlock(&mountlist_mtx); 1036 } 1037 free(pathbuf, M_TEMP); 1038 if (mp == NULL) { 1039 /* 1040 * Previously we returned ENOENT for a nonexistent path and 1041 * EINVAL for a non-mountpoint. We cannot tell these apart 1042 * now, so in the !MNT_BYFSID case return the more likely 1043 * EINVAL for compatibility. 1044 */ 1045 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1046 } 1047 1048 /* 1049 * Only privileged root, or (if MNT_USER is set) the user that did the 1050 * original mount is permitted to unmount this filesystem. 1051 */ 1052 error = vfs_suser(mp, td); 1053 if (error) 1054 return (error); 1055 1056 /* 1057 * Don't allow unmounting the root filesystem. 1058 */ 1059 if (mp->mnt_flag & MNT_ROOTFS) 1060 return (EINVAL); 1061 mtx_lock(&Giant); 1062 error = dounmount(mp, uap->flags, td); 1063 mtx_unlock(&Giant); 1064 return (error); 1065} 1066 1067/* 1068 * Do the actual filesystem unmount. 1069 */ 1070int 1071dounmount(mp, flags, td) 1072 struct mount *mp; 1073 int flags; 1074 struct thread *td; 1075{ 1076 struct vnode *coveredvp, *fsrootvp; 1077 int error; 1078 int async_flag; 1079 1080 mtx_assert(&Giant, MA_OWNED); 1081 1082 mtx_lock(&mountlist_mtx); 1083 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1084 mtx_unlock(&mountlist_mtx); 1085 return (EBUSY); 1086 } 1087 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1088 /* Allow filesystems to detect that a forced unmount is in progress. */ 1089 if (flags & MNT_FORCE) 1090 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1091 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1092 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), &mountlist_mtx, td); 1093 if (error) { 1094 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1095 if (mp->mnt_kern_flag & MNTK_MWAIT) 1096 wakeup(mp); 1097 return (error); 1098 } 1099 vn_start_write(NULL, &mp, V_WAIT); 1100 1101 if (mp->mnt_flag & MNT_EXPUBLIC) 1102 vfs_setpublicfs(NULL, NULL, NULL); 1103 1104 vfs_msync(mp, MNT_WAIT); 1105 async_flag = mp->mnt_flag & MNT_ASYNC; 1106 mp->mnt_flag &= ~MNT_ASYNC; 1107 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1108 if (mp->mnt_syncer != NULL) 1109 vrele(mp->mnt_syncer); 1110 /* 1111 * For forced unmounts, move process cdir/rdir refs on the fs root 1112 * vnode to the covered vnode. For non-forced unmounts we want 1113 * such references to cause an EBUSY error. 1114 */ 1115 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 1116 if (mp->mnt_vnodecovered != NULL) 1117 checkdirs(fsrootvp, mp->mnt_vnodecovered); 1118 if (fsrootvp == rootvnode) { 1119 vrele(rootvnode); 1120 rootvnode = NULL; 1121 } 1122 vput(fsrootvp); 1123 } 1124 if (((mp->mnt_flag & MNT_RDONLY) || 1125 (error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) == 0) || 1126 (flags & MNT_FORCE)) { 1127 error = VFS_UNMOUNT(mp, flags, td); 1128 } 1129 vn_finished_write(mp); 1130 if (error) { 1131 /* Undo cdir/rdir and rootvnode changes made above. */ 1132 if ((flags & MNT_FORCE) && VFS_ROOT(mp, &fsrootvp, td) == 0) { 1133 if (mp->mnt_vnodecovered != NULL) 1134 checkdirs(mp->mnt_vnodecovered, fsrootvp); 1135 if (rootvnode == NULL) { 1136 rootvnode = fsrootvp; 1137 vref(rootvnode); 1138 } 1139 vput(fsrootvp); 1140 } 1141 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) 1142 (void) vfs_allocate_syncvnode(mp); 1143 mtx_lock(&mountlist_mtx); 1144 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1145 mp->mnt_flag |= async_flag; 1146 lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, 1147 &mountlist_mtx, td); 1148 if (mp->mnt_kern_flag & MNTK_MWAIT) 1149 wakeup(mp); 1150 return (error); 1151 } 1152 mtx_lock(&mountlist_mtx); 1153 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1154 if ((coveredvp = mp->mnt_vnodecovered) != NULL) 1155 coveredvp->v_mountedhere = NULL; 1156 mtx_unlock(&mountlist_mtx); 1157 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1158 vfs_mount_destroy(mp, td); 1159 if (coveredvp != NULL) 1160 vrele(coveredvp); 1161 return (0); 1162} 1163 1164/* 1165 * Find and mount the root filesystem 1166 */ 1167void 1168vfs_mountroot(void) 1169{ 1170 char *cp; 1171 int error, i, asked = 0; 1172 1173 1174 /* 1175 * Wait for GEOM to settle down 1176 */ 1177 DROP_GIANT(); 1178 g_waitidle(); 1179 PICKUP_GIANT(); 1180 1181 /* 1182 * We are booted with instructions to prompt for the root filesystem. 1183 */ 1184 if (boothowto & RB_ASKNAME) { 1185 if (!vfs_mountroot_ask()) 1186 return; 1187 asked = 1; 1188 } 1189 1190 /* 1191 * The root filesystem information is compiled in, and we are 1192 * booted with instructions to use it. 1193 */ 1194 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1195 if (!vfs_mountroot_try(ctrootdevname)) 1196 return; 1197 ctrootdevname = NULL; 1198 } 1199 1200 /* 1201 * We've been given the generic "use CDROM as root" flag. This is 1202 * necessary because one media may be used in many different 1203 * devices, so we need to search for them. 1204 */ 1205 if (boothowto & RB_CDROM) { 1206 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1207 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1208 return; 1209 } 1210 } 1211 1212 /* 1213 * Try to use the value read by the loader from /etc/fstab, or 1214 * supplied via some other means. This is the preferred 1215 * mechanism. 1216 */ 1217 cp = getenv("vfs.root.mountfrom"); 1218 if (cp != NULL) { 1219 error = vfs_mountroot_try(cp); 1220 freeenv(cp); 1221 if (!error) 1222 return; 1223 } 1224 1225 /* 1226 * Try values that may have been computed by code during boot 1227 */ 1228 if (!vfs_mountroot_try(rootdevnames[0])) 1229 return; 1230 if (!vfs_mountroot_try(rootdevnames[1])) 1231 return; 1232 1233 /* 1234 * If we (still) have a compiled-in default, try it. 1235 */ 1236 if (ctrootdevname != NULL) 1237 if (!vfs_mountroot_try(ctrootdevname)) 1238 return; 1239 1240 /* 1241 * Everything so far has failed, prompt on the console if we haven't 1242 * already tried that. 1243 */ 1244 if (!asked) 1245 if (!vfs_mountroot_ask()) 1246 return; 1247 panic("Root mount failed, startup aborted."); 1248} 1249 1250/* 1251 * Mount (mountfrom) as the root filesystem. 1252 */ 1253static int 1254vfs_mountroot_try(const char *mountfrom) 1255{ 1256 struct mount *mp; 1257 struct thread *td = curthread; 1258 struct vfsconf *vfsp; 1259 char *vfsname, *path; 1260 int error; 1261 char patt[32]; 1262 int s; 1263 1264 vfsname = NULL; 1265 path = NULL; 1266 mp = NULL; 1267 error = EINVAL; 1268 1269 if (mountfrom == NULL) 1270 return (error); /* don't complain */ 1271 1272 s = splcam(); /* Overkill, but annoying without it */ 1273 printf("Trying to mount root from %s\n", mountfrom); 1274 splx(s); 1275 1276 /* parse vfs name and path */ 1277 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1278 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1279 vfsname[0] = path[0] = 0; 1280 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1281 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1282 goto done; 1283 1284 if (path[0] == '\0') 1285 strcpy(path, ROOTNAME); 1286 1287 vfsp = vfs_byname(vfsname); 1288 if (vfsp == NULL) { 1289 printf("Can't find filesystem \"%s\"\n", vfsname); 1290 goto done; 1291 } 1292 error = vfs_mount_alloc(NULLVP, vfsp, "/", td, &mp); 1293 if (error) { 1294 printf("Could not alloc mountpoint\n"); 1295 goto done; 1296 } 1297 1298 mp->mnt_flag |= MNT_RDONLY | MNT_ROOTFS; 1299 1300 strlcpy(mp->mnt_stat.f_mntfromname, path, MNAMELEN); 1301 1302 /* 1303 * do our best to set rootdev 1304 * XXX: This does not belong here! 1305 */ 1306 if (path[0] != '\0') { 1307 struct cdev *diskdev; 1308 diskdev = getdiskbyname(path); 1309 if (diskdev != NULL) 1310 rootdev = diskdev; 1311 else 1312 printf("setrootbyname failed\n"); 1313 } 1314 1315 error = VFS_OMOUNT(mp, path, NULL, curthread); 1316 1317done: 1318 if (vfsname != NULL) 1319 free(vfsname, M_MOUNT); 1320 if (path != NULL) 1321 free(path, M_MOUNT); 1322 if (error != 0) { 1323 if (mp != NULL) 1324 vfs_mount_destroy(mp, curthread); 1325 printf("Root mount failed: %d\n", error); 1326 } else { 1327 1328 /* register with list of mounted filesystems */ 1329 mtx_lock(&mountlist_mtx); 1330 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1331 mtx_unlock(&mountlist_mtx); 1332 1333 /* sanity check system clock against root fs timestamp */ 1334 inittodr(mp->mnt_time); 1335 vfs_unbusy(mp, curthread); 1336 error = VFS_START(mp, 0, curthread); 1337 } 1338 return (error); 1339} 1340 1341/* 1342 * Spin prompting on the console for a suitable root filesystem 1343 */ 1344static int 1345vfs_mountroot_ask(void) 1346{ 1347 char name[128]; 1348 1349 for(;;) { 1350 printf("\nManual root filesystem specification:\n"); 1351 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1352#if defined(__i386__) || defined(__ia64__) 1353 printf(" eg. ufs:da0s1a\n"); 1354#else 1355 printf(" eg. ufs:/dev/da0a\n"); 1356#endif 1357 printf(" ? List valid disk boot devices\n"); 1358 printf(" <empty line> Abort manual input\n"); 1359 printf("\nmountroot> "); 1360 gets(name); 1361 if (name[0] == '\0') 1362 return (1); 1363 if (name[0] == '?') { 1364 printf("\nList of GEOM managed disk devices:\n "); 1365 g_dev_print(); 1366 continue; 1367 } 1368 if (!vfs_mountroot_try(name)) 1369 return (0); 1370 } 1371} 1372 1373/* 1374 * Local helper function for vfs_mountroot_ask. 1375 */ 1376static void 1377gets(char *cp) 1378{ 1379 char *lp; 1380 int c; 1381 1382 lp = cp; 1383 for (;;) { 1384 printf("%c", c = cngetc() & 0177); 1385 switch (c) { 1386 case -1: 1387 case '\n': 1388 case '\r': 1389 *lp++ = '\0'; 1390 return; 1391 case '\b': 1392 case '\177': 1393 if (lp > cp) { 1394 printf(" \b"); 1395 lp--; 1396 } 1397 continue; 1398 case '#': 1399 lp--; 1400 if (lp < cp) 1401 lp = cp; 1402 continue; 1403 case '@': 1404 case 'u' & 037: 1405 lp = cp; 1406 printf("%c", '\n'); 1407 continue; 1408 default: 1409 *lp++ = c; 1410 } 1411 } 1412} 1413 1414/* 1415 * Convert a given name to the cdev pointer of the device, which is probably 1416 * but not by definition, a disk. Mount a DEVFS (on nothing), look the name 1417 * up, extract the cdev from the vnode and unmount it again. Unfortunately 1418 * we cannot use the vnode directly (because we unmount the DEVFS again) 1419 * so the filesystems still have to do the bdevvp() stunt. 1420 */ 1421static struct cdev * 1422getdiskbyname(char *name) 1423{ 1424 char *cp = name; 1425 struct cdev *dev = NULL; 1426 struct thread *td = curthread; 1427 struct vfsconf *vfsp; 1428 struct mount *mp = NULL; 1429 struct vnode *vroot = NULL; 1430 struct nameidata nid; 1431 int error; 1432 1433 if (!bcmp(cp, "/dev/", 5)) 1434 cp += 5; 1435 1436 do { 1437 vfsp = vfs_byname("devfs"); 1438 if (vfsp == NULL) 1439 break; 1440 error = vfs_mount_alloc(NULLVP, vfsp, "/dev", td, &mp); 1441 if (error) 1442 break; 1443 mp->mnt_flag |= MNT_RDONLY; 1444 1445 error = VFS_MOUNT(mp, curthread); 1446 if (error) 1447 break; 1448 VFS_START(mp, 0, td); 1449 VFS_ROOT(mp, &vroot, td); 1450 VOP_UNLOCK(vroot, 0, td); 1451 1452 NDINIT(&nid, LOOKUP, NOCACHE|FOLLOW, 1453 UIO_SYSSPACE, cp, curthread); 1454 nid.ni_startdir = vroot; 1455 nid.ni_pathlen = strlen(cp); 1456 nid.ni_cnd.cn_cred = curthread->td_ucred; 1457 nid.ni_cnd.cn_nameptr = cp; 1458 1459 error = lookup(&nid); 1460 if (error) 1461 break; 1462 if (nid.ni_vp->v_type != VCHR) 1463 dev = NULL; 1464 else 1465 dev = nid.ni_vp->v_rdev; 1466 NDFREE(&nid, 0); 1467 } while (0); 1468 1469 if (vroot != NULL) 1470 VFS_UNMOUNT(mp, 0, td); 1471 if (mp != NULL) 1472 vfs_mount_destroy(mp, td); 1473 return (dev); 1474} 1475 1476/* Show the struct cdev *for a disk specified by name */ 1477#ifdef DDB 1478DB_SHOW_COMMAND(disk, db_getdiskbyname) 1479{ 1480 struct cdev *dev; 1481 1482 if (modif[0] == '\0') { 1483 db_error("usage: show disk/devicename"); 1484 return; 1485 } 1486 dev = getdiskbyname(modif); 1487 if (dev != NULL) 1488 db_printf("struct cdev *= %p\n", dev); 1489 else 1490 db_printf("No disk device matched.\n"); 1491} 1492#endif 1493 1494/* 1495 * Get a mount option by its name. 1496 * 1497 * Return 0 if the option was found, ENOENT otherwise. 1498 * If len is non-NULL it will be filled with the length 1499 * of the option. If buf is non-NULL, it will be filled 1500 * with the address of the option. 1501 */ 1502int 1503vfs_getopt(opts, name, buf, len) 1504 struct vfsoptlist *opts; 1505 const char *name; 1506 void **buf; 1507 int *len; 1508{ 1509 struct vfsopt *opt; 1510 1511 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1512 1513 TAILQ_FOREACH(opt, opts, link) { 1514 if (strcmp(name, opt->name) == 0) { 1515 if (len != NULL) 1516 *len = opt->len; 1517 if (buf != NULL) 1518 *buf = opt->value; 1519 return (0); 1520 } 1521 } 1522 return (ENOENT); 1523} 1524 1525/* 1526 * Find and copy a mount option. 1527 * 1528 * The size of the buffer has to be specified 1529 * in len, if it is not the same length as the 1530 * mount option, EINVAL is returned. 1531 * Returns ENOENT if the option is not found. 1532 */ 1533int 1534vfs_copyopt(opts, name, dest, len) 1535 struct vfsoptlist *opts; 1536 const char *name; 1537 void *dest; 1538 int len; 1539{ 1540 struct vfsopt *opt; 1541 1542 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1543 1544 TAILQ_FOREACH(opt, opts, link) { 1545 if (strcmp(name, opt->name) == 0) { 1546 if (len != opt->len) 1547 return (EINVAL); 1548 bcopy(opt->value, dest, opt->len); 1549 return (0); 1550 } 1551 } 1552 return (ENOENT); 1553} 1554 1555 1556/* 1557 * This is a helper function for filesystems to traverse their 1558 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1559 */ 1560 1561struct vnode * 1562__mnt_vnode_next(struct vnode **nvp, struct mount *mp) 1563{ 1564 struct vnode *vp; 1565 1566 mtx_assert(&mp->mnt_mtx, MA_OWNED); 1567 1568 vp = *nvp; 1569 /* Check if we are done */ 1570 if (vp == NULL) 1571 return (NULL); 1572 /* If our next vnode is no longer ours, start over */ 1573 if (vp->v_mount != mp) 1574 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 1575 /* Save pointer to next vnode in list */ 1576 if (vp != NULL) 1577 *nvp = TAILQ_NEXT(vp, v_nmntvnodes); 1578 else 1579 *nvp = NULL; 1580 return (vp); 1581} 1582 1583int 1584__vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 1585{ 1586 int error; 1587 1588 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 1589 if (sbp != &mp->mnt_stat) 1590 memcpy(sbp, &mp->mnt_stat, sizeof sbp); 1591 return (error); 1592} 1593