Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_mount.c
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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: releng/8.3/sys/kern/vfs_mount.c 229978 2012-01-11 19:12:29Z mckusick $"); 39 40 #include <sys/param.h> 41 #include <sys/conf.h> 42 #include <sys/fcntl.h> 43 #include <sys/jail.h> 44 #include <sys/kernel.h> 45 #include <sys/libkern.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/namei.h> 50 #include <sys/priv.h> 51 #include <sys/proc.h> 52 #include <sys/filedesc.h> 53 #include <sys/reboot.h> 54 #include <sys/syscallsubr.h> 55 #include <sys/sysproto.h> 56 #include <sys/sx.h> 57 #include <sys/sysctl.h> 58 #include <sys/sysent.h> 59 #include <sys/systm.h> 60 #include <sys/vnode.h> 61 #include <vm/uma.h> 62 63 #include <geom/geom.h> 64 65 #include <machine/stdarg.h> 66 67 #include <security/audit/audit.h> 68 #include <security/mac/mac_framework.h> 69 70 #include "opt_rootdevname.h" 71 72 #define ROOTNAME "root_device" 73 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 74 75 static void set_rootvnode(void); 76 static int vfs_domount(struct thread *td, const char *fstype, 77 char *fspath, int fsflags, void *fsdata); 78 static int vfs_mountroot_ask(void); 79 static int vfs_mountroot_try(const char *mountfrom, const char *options); 80 static void free_mntarg(struct mntarg *ma); 81 82 static int usermount = 0; 83 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 84 "Unprivileged users may mount and unmount file systems"); 85 86 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 87 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 88 static uma_zone_t mount_zone; 89 90 /* List of mounted filesystems. */ 91 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 92 93 /* For any iteration/modification of mountlist */ 94 struct mtx mountlist_mtx; 95 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 96 97 /* 98 * The vnode of the system's root (/ in the filesystem, without chroot 99 * active.) 100 */ 101 struct vnode *rootvnode; 102 103 /* 104 * The root filesystem is detailed in the kernel environment variable 105 * vfs.root.mountfrom, which is expected to be in the general format 106 * 107 * <vfsname>:[<path>][ <vfsname>:[<path>] ...] 108 * vfsname := the name of a VFS known to the kernel and capable 109 * of being mounted as root 110 * path := disk device name or other data used by the filesystem 111 * to locate its physical store 112 * 113 * If the environment variable vfs.root.mountfrom is a space separated list, 114 * each list element is tried in turn and the root filesystem will be mounted 115 * from the first one that suceeds. 116 * 117 * The environment variable vfs.root.mountfrom.options is a comma delimited 118 * set of string mount options. These mount options must be parseable 119 * by nmount() in the kernel. 120 */ 121 122 /* 123 * Global opts, taken by all filesystems 124 */ 125 static const char *global_opts[] = { 126 "errmsg", 127 "fstype", 128 "fspath", 129 "ro", 130 "rw", 131 "nosuid", 132 "noexec", 133 NULL 134 }; 135 136 /* 137 * The root specifiers we will try if RB_CDROM is specified. 138 */ 139 static char *cdrom_rootdevnames[] = { 140 "cd9660:cd0", 141 "cd9660:acd0", 142 NULL 143 }; 144 145 /* legacy find-root code */ 146 char *rootdevnames[2] = {NULL, NULL}; 147 #ifndef ROOTDEVNAME 148 # define ROOTDEVNAME NULL 149 #endif 150 static const char *ctrootdevname = ROOTDEVNAME; 151 152 /* 153 * --------------------------------------------------------------------- 154 * Functions for building and sanitizing the mount options 155 */ 156 157 /* Remove one mount option. */ 158 static void 159 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 160 { 161 162 TAILQ_REMOVE(opts, opt, link); 163 free(opt->name, M_MOUNT); 164 if (opt->value != NULL) 165 free(opt->value, M_MOUNT); 166 free(opt, M_MOUNT); 167 } 168 169 /* Release all resources related to the mount options. */ 170 void 171 vfs_freeopts(struct vfsoptlist *opts) 172 { 173 struct vfsopt *opt; 174 175 while (!TAILQ_EMPTY(opts)) { 176 opt = TAILQ_FIRST(opts); 177 vfs_freeopt(opts, opt); 178 } 179 free(opts, M_MOUNT); 180 } 181 182 void 183 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 184 { 185 struct vfsopt *opt, *temp; 186 187 if (opts == NULL) 188 return; 189 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 190 if (strcmp(opt->name, name) == 0) 191 vfs_freeopt(opts, opt); 192 } 193 } 194 195 static int 196 vfs_isopt_ro(const char *opt) 197 { 198 199 if (strcmp(opt, "ro") == 0 || strcmp(opt, "rdonly") == 0 || 200 strcmp(opt, "norw") == 0) 201 return (1); 202 return (0); 203 } 204 205 static int 206 vfs_isopt_rw(const char *opt) 207 { 208 209 if (strcmp(opt, "rw") == 0 || strcmp(opt, "noro") == 0) 210 return (1); 211 return (0); 212 } 213 214 /* 215 * Check if options are equal (with or without the "no" prefix). 216 */ 217 static int 218 vfs_equalopts(const char *opt1, const char *opt2) 219 { 220 char *p; 221 222 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 223 if (strcmp(opt1, opt2) == 0) 224 return (1); 225 /* "noopt" vs. "opt" */ 226 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 227 return (1); 228 /* "opt" vs. "noopt" */ 229 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 230 return (1); 231 while ((p = strchr(opt1, '.')) != NULL && 232 !strncmp(opt1, opt2, ++p - opt1)) { 233 opt2 += p - opt1; 234 opt1 = p; 235 /* "foo.noopt" vs. "foo.opt" */ 236 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 237 return (1); 238 /* "foo.opt" vs. "foo.noopt" */ 239 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 240 return (1); 241 } 242 /* "ro" / "rdonly" / "norw" / "rw" / "noro" */ 243 if ((vfs_isopt_ro(opt1) || vfs_isopt_rw(opt1)) && 244 (vfs_isopt_ro(opt2) || vfs_isopt_rw(opt2))) 245 return (1); 246 return (0); 247 } 248 249 /* 250 * If a mount option is specified several times, 251 * (with or without the "no" prefix) only keep 252 * the last occurence of it. 253 */ 254 static void 255 vfs_sanitizeopts(struct vfsoptlist *opts) 256 { 257 struct vfsopt *opt, *opt2, *tmp; 258 259 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 260 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 261 while (opt2 != NULL) { 262 if (vfs_equalopts(opt->name, opt2->name)) { 263 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 264 vfs_freeopt(opts, opt2); 265 opt2 = tmp; 266 } else { 267 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 268 } 269 } 270 } 271 } 272 273 /* 274 * Build a linked list of mount options from a struct uio. 275 */ 276 int 277 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 278 { 279 struct vfsoptlist *opts; 280 struct vfsopt *opt; 281 size_t memused, namelen, optlen; 282 unsigned int i, iovcnt; 283 int error; 284 285 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 286 TAILQ_INIT(opts); 287 memused = 0; 288 iovcnt = auio->uio_iovcnt; 289 for (i = 0; i < iovcnt; i += 2) { 290 namelen = auio->uio_iov[i].iov_len; 291 optlen = auio->uio_iov[i + 1].iov_len; 292 memused += sizeof(struct vfsopt) + optlen + namelen; 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 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 305 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 306 opt->value = NULL; 307 opt->len = 0; 308 opt->pos = i / 2; 309 opt->seen = 0; 310 311 /* 312 * Do this early, so jumps to "bad" will free the current 313 * option. 314 */ 315 TAILQ_INSERT_TAIL(opts, opt, link); 316 317 if (auio->uio_segflg == UIO_SYSSPACE) { 318 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 319 } else { 320 error = copyin(auio->uio_iov[i].iov_base, opt->name, 321 namelen); 322 if (error) 323 goto bad; 324 } 325 /* Ensure names are null-terminated strings. */ 326 if (namelen == 0 || opt->name[namelen - 1] != '\0') { 327 error = EINVAL; 328 goto bad; 329 } 330 if (optlen != 0) { 331 opt->len = optlen; 332 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 333 if (auio->uio_segflg == UIO_SYSSPACE) { 334 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 335 optlen); 336 } else { 337 error = copyin(auio->uio_iov[i + 1].iov_base, 338 opt->value, optlen); 339 if (error) 340 goto bad; 341 } 342 } 343 } 344 vfs_sanitizeopts(opts); 345 *options = opts; 346 return (0); 347 bad: 348 vfs_freeopts(opts); 349 return (error); 350 } 351 352 /* 353 * Merge the old mount options with the new ones passed 354 * in the MNT_UPDATE case. 355 * 356 * XXX This function will keep a "nofoo" option in the 357 * new options if there is no matching "foo" option 358 * to be cancelled in the old options. This is a bug 359 * if the option's canonical name is "foo". E.g., "noro" 360 * shouldn't end up in the mount point's active options, 361 * but it can. 362 */ 363 static void 364 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 365 { 366 struct vfsopt *opt, *opt2, *new; 367 368 TAILQ_FOREACH(opt, opts, link) { 369 /* 370 * Check that this option hasn't been redefined 371 * nor cancelled with a "no" mount option. 372 */ 373 opt2 = TAILQ_FIRST(toopts); 374 while (opt2 != NULL) { 375 if (strcmp(opt2->name, opt->name) == 0) 376 goto next; 377 if (strncmp(opt2->name, "no", 2) == 0 && 378 strcmp(opt2->name + 2, opt->name) == 0) { 379 vfs_freeopt(toopts, opt2); 380 goto next; 381 } 382 opt2 = TAILQ_NEXT(opt2, link); 383 } 384 /* We want this option, duplicate it. */ 385 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 386 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 387 strcpy(new->name, opt->name); 388 if (opt->len != 0) { 389 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 390 bcopy(opt->value, new->value, opt->len); 391 } else { 392 new->value = NULL; 393 } 394 new->len = opt->len; 395 new->seen = opt->seen; 396 TAILQ_INSERT_TAIL(toopts, new, link); 397 next: 398 continue; 399 } 400 } 401 402 /* 403 * Mount a filesystem. 404 */ 405 int 406 nmount(td, uap) 407 struct thread *td; 408 struct nmount_args /* { 409 struct iovec *iovp; 410 unsigned int iovcnt; 411 int flags; 412 } */ *uap; 413 { 414 struct uio *auio; 415 int error; 416 u_int iovcnt; 417 418 AUDIT_ARG_FFLAGS(uap->flags); 419 CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__, 420 uap->iovp, uap->iovcnt, uap->flags); 421 422 /* 423 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 424 * userspace to set this flag, but we must filter it out if we want 425 * MNT_UPDATE on the root file system to work. 426 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 427 */ 428 uap->flags &= ~MNT_ROOTFS; 429 430 iovcnt = uap->iovcnt; 431 /* 432 * Check that we have an even number of iovec's 433 * and that we have at least two options. 434 */ 435 if ((iovcnt & 1) || (iovcnt < 4)) { 436 CTR2(KTR_VFS, "%s: failed for invalid iovcnt %d", __func__, 437 uap->iovcnt); 438 return (EINVAL); 439 } 440 441 error = copyinuio(uap->iovp, iovcnt, &auio); 442 if (error) { 443 CTR2(KTR_VFS, "%s: failed for invalid uio op with %d errno", 444 __func__, error); 445 return (error); 446 } 447 error = vfs_donmount(td, uap->flags, auio); 448 449 free(auio, M_IOV); 450 return (error); 451 } 452 453 /* 454 * --------------------------------------------------------------------- 455 * Various utility functions 456 */ 457 458 void 459 vfs_ref(struct mount *mp) 460 { 461 462 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 463 MNT_ILOCK(mp); 464 MNT_REF(mp); 465 MNT_IUNLOCK(mp); 466 } 467 468 void 469 vfs_rel(struct mount *mp) 470 { 471 472 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 473 MNT_ILOCK(mp); 474 MNT_REL(mp); 475 MNT_IUNLOCK(mp); 476 } 477 478 static int 479 mount_init(void *mem, int size, int flags) 480 { 481 struct mount *mp; 482 483 mp = (struct mount *)mem; 484 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 485 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 486 return (0); 487 } 488 489 static void 490 mount_fini(void *mem, int size) 491 { 492 struct mount *mp; 493 494 mp = (struct mount *)mem; 495 lockdestroy(&mp->mnt_explock); 496 mtx_destroy(&mp->mnt_mtx); 497 } 498 499 /* 500 * Allocate and initialize the mount point struct. 501 */ 502 struct mount * 503 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, const char *fspath, 504 struct ucred *cred) 505 { 506 struct mount *mp; 507 508 mp = uma_zalloc(mount_zone, M_WAITOK); 509 bzero(&mp->mnt_startzero, 510 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 511 TAILQ_INIT(&mp->mnt_nvnodelist); 512 mp->mnt_nvnodelistsize = 0; 513 mp->mnt_ref = 0; 514 (void) vfs_busy(mp, MBF_NOWAIT); 515 mp->mnt_op = vfsp->vfc_vfsops; 516 mp->mnt_vfc = vfsp; 517 vfsp->vfc_refcount++; /* XXX Unlocked */ 518 mp->mnt_stat.f_type = vfsp->vfc_typenum; 519 mp->mnt_gen++; 520 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 521 mp->mnt_vnodecovered = vp; 522 mp->mnt_cred = crdup(cred); 523 mp->mnt_stat.f_owner = cred->cr_uid; 524 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 525 mp->mnt_iosize_max = DFLTPHYS; 526 #ifdef MAC 527 mac_mount_init(mp); 528 mac_mount_create(cred, mp); 529 #endif 530 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 531 return (mp); 532 } 533 534 /* 535 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 536 */ 537 void 538 vfs_mount_destroy(struct mount *mp) 539 { 540 541 MNT_ILOCK(mp); 542 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 543 if (mp->mnt_kern_flag & MNTK_MWAIT) { 544 mp->mnt_kern_flag &= ~MNTK_MWAIT; 545 wakeup(mp); 546 } 547 while (mp->mnt_ref) 548 msleep(mp, MNT_MTX(mp), PVFS, "mntref", 0); 549 KASSERT(mp->mnt_ref == 0, 550 ("%s: invalid refcount in the drain path @ %s:%d", __func__, 551 __FILE__, __LINE__)); 552 if (mp->mnt_writeopcount != 0) 553 panic("vfs_mount_destroy: nonzero writeopcount"); 554 if (mp->mnt_secondary_writes != 0) 555 panic("vfs_mount_destroy: nonzero secondary_writes"); 556 mp->mnt_vfc->vfc_refcount--; 557 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 558 struct vnode *vp; 559 560 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 561 vprint("", vp); 562 panic("unmount: dangling vnode"); 563 } 564 if (mp->mnt_nvnodelistsize != 0) 565 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 566 if (mp->mnt_lockref != 0) 567 panic("vfs_mount_destroy: nonzero lock refcount"); 568 MNT_IUNLOCK(mp); 569 #ifdef MAC 570 mac_mount_destroy(mp); 571 #endif 572 if (mp->mnt_opt != NULL) 573 vfs_freeopts(mp->mnt_opt); 574 crfree(mp->mnt_cred); 575 uma_zfree(mount_zone, mp); 576 } 577 578 int 579 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 580 { 581 struct vfsoptlist *optlist; 582 struct vfsopt *opt, *noro_opt, *tmp_opt; 583 char *fstype, *fspath, *errmsg; 584 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 585 int has_rw, has_noro; 586 587 errmsg = fspath = NULL; 588 errmsg_len = has_noro = has_rw = fspathlen = 0; 589 errmsg_pos = -1; 590 591 error = vfs_buildopts(fsoptions, &optlist); 592 if (error) 593 return (error); 594 595 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 596 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 597 598 /* 599 * We need these two options before the others, 600 * and they are mandatory for any filesystem. 601 * Ensure they are NUL terminated as well. 602 */ 603 fstypelen = 0; 604 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 605 if (error || fstype[fstypelen - 1] != '\0') { 606 error = EINVAL; 607 if (errmsg != NULL) 608 strncpy(errmsg, "Invalid fstype", errmsg_len); 609 goto bail; 610 } 611 fspathlen = 0; 612 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 613 if (error || fspath[fspathlen - 1] != '\0') { 614 error = EINVAL; 615 if (errmsg != NULL) 616 strncpy(errmsg, "Invalid fspath", errmsg_len); 617 goto bail; 618 } 619 620 /* 621 * We need to see if we have the "update" option 622 * before we call vfs_domount(), since vfs_domount() has special 623 * logic based on MNT_UPDATE. This is very important 624 * when we want to update the root filesystem. 625 */ 626 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 627 if (strcmp(opt->name, "update") == 0) { 628 fsflags |= MNT_UPDATE; 629 vfs_freeopt(optlist, opt); 630 } 631 else if (strcmp(opt->name, "async") == 0) 632 fsflags |= MNT_ASYNC; 633 else if (strcmp(opt->name, "force") == 0) { 634 fsflags |= MNT_FORCE; 635 vfs_freeopt(optlist, opt); 636 } 637 else if (strcmp(opt->name, "reload") == 0) { 638 fsflags |= MNT_RELOAD; 639 vfs_freeopt(optlist, opt); 640 } 641 else if (strcmp(opt->name, "multilabel") == 0) 642 fsflags |= MNT_MULTILABEL; 643 else if (strcmp(opt->name, "noasync") == 0) 644 fsflags &= ~MNT_ASYNC; 645 else if (strcmp(opt->name, "noatime") == 0) 646 fsflags |= MNT_NOATIME; 647 else if (strcmp(opt->name, "atime") == 0) { 648 free(opt->name, M_MOUNT); 649 opt->name = strdup("nonoatime", M_MOUNT); 650 } 651 else if (strcmp(opt->name, "noclusterr") == 0) 652 fsflags |= MNT_NOCLUSTERR; 653 else if (strcmp(opt->name, "clusterr") == 0) { 654 free(opt->name, M_MOUNT); 655 opt->name = strdup("nonoclusterr", M_MOUNT); 656 } 657 else if (strcmp(opt->name, "noclusterw") == 0) 658 fsflags |= MNT_NOCLUSTERW; 659 else if (strcmp(opt->name, "clusterw") == 0) { 660 free(opt->name, M_MOUNT); 661 opt->name = strdup("nonoclusterw", M_MOUNT); 662 } 663 else if (strcmp(opt->name, "noexec") == 0) 664 fsflags |= MNT_NOEXEC; 665 else if (strcmp(opt->name, "exec") == 0) { 666 free(opt->name, M_MOUNT); 667 opt->name = strdup("nonoexec", M_MOUNT); 668 } 669 else if (strcmp(opt->name, "nosuid") == 0) 670 fsflags |= MNT_NOSUID; 671 else if (strcmp(opt->name, "suid") == 0) { 672 free(opt->name, M_MOUNT); 673 opt->name = strdup("nonosuid", M_MOUNT); 674 } 675 else if (strcmp(opt->name, "nosymfollow") == 0) 676 fsflags |= MNT_NOSYMFOLLOW; 677 else if (strcmp(opt->name, "symfollow") == 0) { 678 free(opt->name, M_MOUNT); 679 opt->name = strdup("nonosymfollow", M_MOUNT); 680 } 681 else if (strcmp(opt->name, "noro") == 0) { 682 fsflags &= ~MNT_RDONLY; 683 has_noro = 1; 684 } 685 else if (strcmp(opt->name, "rw") == 0) { 686 fsflags &= ~MNT_RDONLY; 687 has_rw = 1; 688 } 689 else if (strcmp(opt->name, "ro") == 0) 690 fsflags |= MNT_RDONLY; 691 else if (strcmp(opt->name, "rdonly") == 0) { 692 free(opt->name, M_MOUNT); 693 opt->name = strdup("ro", M_MOUNT); 694 fsflags |= MNT_RDONLY; 695 } 696 else if (strcmp(opt->name, "suiddir") == 0) 697 fsflags |= MNT_SUIDDIR; 698 else if (strcmp(opt->name, "sync") == 0) 699 fsflags |= MNT_SYNCHRONOUS; 700 else if (strcmp(opt->name, "union") == 0) 701 fsflags |= MNT_UNION; 702 } 703 704 /* 705 * If "rw" was specified as a mount option, and we 706 * are trying to update a mount-point from "ro" to "rw", 707 * we need a mount option "noro", since in vfs_mergeopts(), 708 * "noro" will cancel "ro", but "rw" will not do anything. 709 */ 710 if (has_rw && !has_noro) { 711 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 712 noro_opt->name = strdup("noro", M_MOUNT); 713 noro_opt->value = NULL; 714 noro_opt->len = 0; 715 noro_opt->pos = -1; 716 noro_opt->seen = 1; 717 TAILQ_INSERT_TAIL(optlist, noro_opt, link); 718 } 719 720 /* 721 * Be ultra-paranoid about making sure the type and fspath 722 * variables will fit in our mp buffers, including the 723 * terminating NUL. 724 */ 725 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 726 error = ENAMETOOLONG; 727 goto bail; 728 } 729 730 mtx_lock(&Giant); 731 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 732 mtx_unlock(&Giant); 733 bail: 734 /* copyout the errmsg */ 735 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 736 && errmsg_len > 0 && errmsg != NULL) { 737 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 738 bcopy(errmsg, 739 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 740 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 741 } else { 742 copyout(errmsg, 743 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 744 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 745 } 746 } 747 748 if (error != 0) 749 vfs_freeopts(optlist); 750 return (error); 751 } 752 753 /* 754 * Old mount API. 755 */ 756 #ifndef _SYS_SYSPROTO_H_ 757 struct mount_args { 758 char *type; 759 char *path; 760 int flags; 761 caddr_t data; 762 }; 763 #endif 764 /* ARGSUSED */ 765 int 766 mount(td, uap) 767 struct thread *td; 768 struct mount_args /* { 769 char *type; 770 char *path; 771 int flags; 772 caddr_t data; 773 } */ *uap; 774 { 775 char *fstype; 776 struct vfsconf *vfsp = NULL; 777 struct mntarg *ma = NULL; 778 int error; 779 780 AUDIT_ARG_FFLAGS(uap->flags); 781 782 /* 783 * Filter out MNT_ROOTFS. We do not want clients of mount() in 784 * userspace to set this flag, but we must filter it out if we want 785 * MNT_UPDATE on the root file system to work. 786 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 787 */ 788 uap->flags &= ~MNT_ROOTFS; 789 790 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 791 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 792 if (error) { 793 free(fstype, M_TEMP); 794 return (error); 795 } 796 797 AUDIT_ARG_TEXT(fstype); 798 mtx_lock(&Giant); 799 vfsp = vfs_byname_kld(fstype, td, &error); 800 free(fstype, M_TEMP); 801 if (vfsp == NULL) { 802 mtx_unlock(&Giant); 803 return (ENOENT); 804 } 805 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 806 mtx_unlock(&Giant); 807 return (EOPNOTSUPP); 808 } 809 810 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 811 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 812 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 813 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 814 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 815 816 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags); 817 mtx_unlock(&Giant); 818 return (error); 819 } 820 821 822 /* 823 * vfs_domount(): actually attempt a filesystem mount. 824 */ 825 static int 826 vfs_domount( 827 struct thread *td, /* Calling thread. */ 828 const char *fstype, /* Filesystem type. */ 829 char *fspath, /* Mount path. */ 830 int fsflags, /* Flags common to all filesystems. */ 831 void *fsdata /* Options local to the filesystem. */ 832 ) 833 { 834 struct vnode *vp; 835 struct mount *mp; 836 struct vfsconf *vfsp; 837 struct oexport_args oexport; 838 struct export_args export; 839 int error, flag = 0; 840 struct vattr va; 841 struct nameidata nd; 842 843 mtx_assert(&Giant, MA_OWNED); 844 /* 845 * Be ultra-paranoid about making sure the type and fspath 846 * variables will fit in our mp buffers, including the 847 * terminating NUL. 848 */ 849 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 850 return (ENAMETOOLONG); 851 852 if (jailed(td->td_ucred) || usermount == 0) { 853 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 854 return (error); 855 } 856 857 /* 858 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 859 */ 860 if (fsflags & MNT_EXPORTED) { 861 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 862 if (error) 863 return (error); 864 } 865 if (fsflags & MNT_SUIDDIR) { 866 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 867 if (error) 868 return (error); 869 } 870 /* 871 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 872 */ 873 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 874 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 875 fsflags |= MNT_NOSUID | MNT_USER; 876 } 877 878 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 879 vfsp = NULL; 880 if ((fsflags & MNT_UPDATE) == 0) { 881 /* Don't try to load KLDs if we're mounting the root. */ 882 if (fsflags & MNT_ROOTFS) 883 vfsp = vfs_byname(fstype); 884 else 885 vfsp = vfs_byname_kld(fstype, td, &error); 886 if (vfsp == NULL) 887 return (ENODEV); 888 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 889 return (EPERM); 890 } 891 /* 892 * Get vnode to be covered 893 */ 894 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 895 fspath, td); 896 if ((error = namei(&nd)) != 0) 897 return (error); 898 NDFREE(&nd, NDF_ONLY_PNBUF); 899 vp = nd.ni_vp; 900 if (fsflags & MNT_UPDATE) { 901 if ((vp->v_vflag & VV_ROOT) == 0) { 902 vput(vp); 903 return (EINVAL); 904 } 905 mp = vp->v_mount; 906 MNT_ILOCK(mp); 907 flag = mp->mnt_flag; 908 /* 909 * We only allow the filesystem to be reloaded if it 910 * is currently mounted read-only. 911 */ 912 if ((fsflags & MNT_RELOAD) && 913 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 914 MNT_IUNLOCK(mp); 915 vput(vp); 916 return (EOPNOTSUPP); /* Needs translation */ 917 } 918 MNT_IUNLOCK(mp); 919 /* 920 * Only privileged root, or (if MNT_USER is set) the user that 921 * did the original mount is permitted to update it. 922 */ 923 error = vfs_suser(mp, td); 924 if (error) { 925 vput(vp); 926 return (error); 927 } 928 if (vfs_busy(mp, MBF_NOWAIT)) { 929 vput(vp); 930 return (EBUSY); 931 } 932 VI_LOCK(vp); 933 if ((vp->v_iflag & VI_MOUNT) != 0 || 934 vp->v_mountedhere != NULL) { 935 VI_UNLOCK(vp); 936 vfs_unbusy(mp); 937 vput(vp); 938 return (EBUSY); 939 } 940 vp->v_iflag |= VI_MOUNT; 941 VI_UNLOCK(vp); 942 MNT_ILOCK(mp); 943 mp->mnt_flag |= fsflags & 944 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 945 MNT_IUNLOCK(mp); 946 VOP_UNLOCK(vp, 0); 947 mp->mnt_optnew = fsdata; 948 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 949 } else { 950 /* 951 * If the user is not root, ensure that they own the directory 952 * onto which we are attempting to mount. 953 */ 954 error = VOP_GETATTR(vp, &va, td->td_ucred); 955 if (error) { 956 vput(vp); 957 return (error); 958 } 959 if (va.va_uid != td->td_ucred->cr_uid) { 960 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 961 0); 962 if (error) { 963 vput(vp); 964 return (error); 965 } 966 } 967 error = vinvalbuf(vp, V_SAVE, 0, 0); 968 if (error != 0) { 969 vput(vp); 970 return (error); 971 } 972 if (vp->v_type != VDIR) { 973 vput(vp); 974 return (ENOTDIR); 975 } 976 VI_LOCK(vp); 977 if ((vp->v_iflag & VI_MOUNT) != 0 || 978 vp->v_mountedhere != NULL) { 979 VI_UNLOCK(vp); 980 vput(vp); 981 return (EBUSY); 982 } 983 vp->v_iflag |= VI_MOUNT; 984 VI_UNLOCK(vp); 985 986 /* 987 * Allocate and initialize the filesystem. 988 */ 989 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 990 VOP_UNLOCK(vp, 0); 991 992 /* XXXMAC: pass to vfs_mount_alloc? */ 993 mp->mnt_optnew = fsdata; 994 } 995 996 /* 997 * Set the mount level flags. 998 */ 999 MNT_ILOCK(mp); 1000 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 1001 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 1002 MNT_RDONLY)); 1003 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1004 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1005 MNT_IUNLOCK(mp); 1006 /* 1007 * Mount the filesystem. 1008 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1009 * get. No freeing of cn_pnbuf. 1010 */ 1011 error = VFS_MOUNT(mp); 1012 1013 /* 1014 * Process the export option only if we are 1015 * updating mount options. 1016 */ 1017 if (!error && (fsflags & MNT_UPDATE)) { 1018 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1019 sizeof(export)) == 0) 1020 error = vfs_export(mp, &export); 1021 else if (vfs_copyopt(mp->mnt_optnew, "export", &oexport, 1022 sizeof(oexport)) == 0) { 1023 export.ex_flags = oexport.ex_flags; 1024 export.ex_root = oexport.ex_root; 1025 export.ex_anon = oexport.ex_anon; 1026 export.ex_addr = oexport.ex_addr; 1027 export.ex_addrlen = oexport.ex_addrlen; 1028 export.ex_mask = oexport.ex_mask; 1029 export.ex_masklen = oexport.ex_masklen; 1030 export.ex_indexfile = oexport.ex_indexfile; 1031 export.ex_numsecflavors = 0; 1032 error = vfs_export(mp, &export); 1033 } 1034 } 1035 1036 if (!error) { 1037 if (mp->mnt_opt != NULL) 1038 vfs_freeopts(mp->mnt_opt); 1039 mp->mnt_opt = mp->mnt_optnew; 1040 (void)VFS_STATFS(mp, &mp->mnt_stat); 1041 } 1042 /* 1043 * Prevent external consumers of mount options from reading 1044 * mnt_optnew. 1045 */ 1046 mp->mnt_optnew = NULL; 1047 if (mp->mnt_flag & MNT_UPDATE) { 1048 MNT_ILOCK(mp); 1049 if (error) 1050 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1051 (flag & ~MNT_QUOTA); 1052 else 1053 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1054 MNT_FORCE | MNT_SNAPSHOT); 1055 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1056 mp->mnt_kern_flag |= MNTK_ASYNC; 1057 else 1058 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1059 MNT_IUNLOCK(mp); 1060 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1061 if (mp->mnt_syncer == NULL) 1062 error = vfs_allocate_syncvnode(mp); 1063 } else { 1064 if (mp->mnt_syncer != NULL) 1065 vrele(mp->mnt_syncer); 1066 mp->mnt_syncer = NULL; 1067 } 1068 vfs_unbusy(mp); 1069 VI_LOCK(vp); 1070 vp->v_iflag &= ~VI_MOUNT; 1071 VI_UNLOCK(vp); 1072 vrele(vp); 1073 return (error); 1074 } 1075 MNT_ILOCK(mp); 1076 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1077 mp->mnt_kern_flag |= MNTK_ASYNC; 1078 else 1079 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1080 MNT_IUNLOCK(mp); 1081 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1082 /* 1083 * Put the new filesystem on the mount list after root. 1084 */ 1085 cache_purge(vp); 1086 if (!error) { 1087 struct vnode *newdp; 1088 1089 VI_LOCK(vp); 1090 vp->v_iflag &= ~VI_MOUNT; 1091 VI_UNLOCK(vp); 1092 vp->v_mountedhere = mp; 1093 mtx_lock(&mountlist_mtx); 1094 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1095 mtx_unlock(&mountlist_mtx); 1096 vfs_event_signal(NULL, VQ_MOUNT, 0); 1097 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) 1098 panic("mount: lost mount"); 1099 VOP_UNLOCK(newdp, 0); 1100 VOP_UNLOCK(vp, 0); 1101 mountcheckdirs(vp, newdp); 1102 vrele(newdp); 1103 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1104 error = vfs_allocate_syncvnode(mp); 1105 vfs_unbusy(mp); 1106 if (error) 1107 vrele(vp); 1108 } else { 1109 VI_LOCK(vp); 1110 vp->v_iflag &= ~VI_MOUNT; 1111 VI_UNLOCK(vp); 1112 vfs_unbusy(mp); 1113 vfs_mount_destroy(mp); 1114 vput(vp); 1115 } 1116 return (error); 1117 } 1118 1119 /* 1120 * Unmount a filesystem. 1121 * 1122 * Note: unmount takes a path to the vnode mounted on as argument, not 1123 * special file (as before). 1124 */ 1125 #ifndef _SYS_SYSPROTO_H_ 1126 struct unmount_args { 1127 char *path; 1128 int flags; 1129 }; 1130 #endif 1131 /* ARGSUSED */ 1132 int 1133 unmount(td, uap) 1134 struct thread *td; 1135 register struct unmount_args /* { 1136 char *path; 1137 int flags; 1138 } */ *uap; 1139 { 1140 struct mount *mp; 1141 char *pathbuf; 1142 int error, id0, id1; 1143 1144 AUDIT_ARG_VALUE(uap->flags); 1145 if (jailed(td->td_ucred) || usermount == 0) { 1146 error = priv_check(td, PRIV_VFS_UNMOUNT); 1147 if (error) 1148 return (error); 1149 } 1150 1151 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1152 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1153 if (error) { 1154 free(pathbuf, M_TEMP); 1155 return (error); 1156 } 1157 mtx_lock(&Giant); 1158 if (uap->flags & MNT_BYFSID) { 1159 AUDIT_ARG_TEXT(pathbuf); 1160 /* Decode the filesystem ID. */ 1161 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1162 mtx_unlock(&Giant); 1163 free(pathbuf, M_TEMP); 1164 return (EINVAL); 1165 } 1166 1167 mtx_lock(&mountlist_mtx); 1168 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1169 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1170 mp->mnt_stat.f_fsid.val[1] == id1) 1171 break; 1172 } 1173 mtx_unlock(&mountlist_mtx); 1174 } else { 1175 AUDIT_ARG_UPATH1(td, pathbuf); 1176 mtx_lock(&mountlist_mtx); 1177 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1178 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1179 break; 1180 } 1181 mtx_unlock(&mountlist_mtx); 1182 } 1183 free(pathbuf, M_TEMP); 1184 if (mp == NULL) { 1185 /* 1186 * Previously we returned ENOENT for a nonexistent path and 1187 * EINVAL for a non-mountpoint. We cannot tell these apart 1188 * now, so in the !MNT_BYFSID case return the more likely 1189 * EINVAL for compatibility. 1190 */ 1191 mtx_unlock(&Giant); 1192 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1193 } 1194 1195 /* 1196 * Don't allow unmounting the root filesystem. 1197 */ 1198 if (mp->mnt_flag & MNT_ROOTFS) { 1199 mtx_unlock(&Giant); 1200 return (EINVAL); 1201 } 1202 error = dounmount(mp, uap->flags, td); 1203 mtx_unlock(&Giant); 1204 return (error); 1205 } 1206 1207 /* 1208 * Do the actual filesystem unmount. 1209 */ 1210 int 1211 dounmount(mp, flags, td) 1212 struct mount *mp; 1213 int flags; 1214 struct thread *td; 1215 { 1216 struct vnode *coveredvp, *fsrootvp; 1217 int error; 1218 int async_flag; 1219 int mnt_gen_r; 1220 1221 mtx_assert(&Giant, MA_OWNED); 1222 1223 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1224 mnt_gen_r = mp->mnt_gen; 1225 VI_LOCK(coveredvp); 1226 vholdl(coveredvp); 1227 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1228 vdrop(coveredvp); 1229 /* 1230 * Check for mp being unmounted while waiting for the 1231 * covered vnode lock. 1232 */ 1233 if (coveredvp->v_mountedhere != mp || 1234 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1235 VOP_UNLOCK(coveredvp, 0); 1236 return (EBUSY); 1237 } 1238 } 1239 /* 1240 * Only privileged root, or (if MNT_USER is set) the user that did the 1241 * original mount is permitted to unmount this filesystem. 1242 */ 1243 error = vfs_suser(mp, td); 1244 if (error) { 1245 if (coveredvp) 1246 VOP_UNLOCK(coveredvp, 0); 1247 return (error); 1248 } 1249 1250 MNT_ILOCK(mp); 1251 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1252 MNT_IUNLOCK(mp); 1253 if (coveredvp) 1254 VOP_UNLOCK(coveredvp, 0); 1255 return (EBUSY); 1256 } 1257 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1258 /* Allow filesystems to detect that a forced unmount is in progress. */ 1259 if (flags & MNT_FORCE) 1260 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1261 error = 0; 1262 if (mp->mnt_lockref) { 1263 mp->mnt_kern_flag |= MNTK_DRAINING; 1264 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1265 "mount drain", 0); 1266 } 1267 MNT_IUNLOCK(mp); 1268 KASSERT(mp->mnt_lockref == 0, 1269 ("%s: invalid lock refcount in the drain path @ %s:%d", 1270 __func__, __FILE__, __LINE__)); 1271 KASSERT(error == 0, 1272 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1273 __func__, __FILE__, __LINE__)); 1274 vn_start_write(NULL, &mp, V_WAIT); 1275 1276 if (mp->mnt_flag & MNT_EXPUBLIC) 1277 vfs_setpublicfs(NULL, NULL, NULL); 1278 1279 vfs_msync(mp, MNT_WAIT); 1280 MNT_ILOCK(mp); 1281 async_flag = mp->mnt_flag & MNT_ASYNC; 1282 mp->mnt_flag &= ~MNT_ASYNC; 1283 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1284 MNT_IUNLOCK(mp); 1285 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1286 if (mp->mnt_syncer != NULL) 1287 vrele(mp->mnt_syncer); 1288 /* 1289 * For forced unmounts, move process cdir/rdir refs on the fs root 1290 * vnode to the covered vnode. For non-forced unmounts we want 1291 * such references to cause an EBUSY error. 1292 */ 1293 if ((flags & MNT_FORCE) && 1294 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1295 if (mp->mnt_vnodecovered != NULL) 1296 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1297 if (fsrootvp == rootvnode) { 1298 vrele(rootvnode); 1299 rootvnode = NULL; 1300 } 1301 vput(fsrootvp); 1302 } 1303 if (((mp->mnt_flag & MNT_RDONLY) || 1304 (error = VFS_SYNC(mp, MNT_WAIT)) == 0) || (flags & MNT_FORCE) != 0) 1305 error = VFS_UNMOUNT(mp, flags); 1306 vn_finished_write(mp); 1307 /* 1308 * If we failed to flush the dirty blocks for this mount point, 1309 * undo all the cdir/rdir and rootvnode changes we made above. 1310 * Unless we failed to do so because the device is reporting that 1311 * it doesn't exist anymore. 1312 */ 1313 if (error && error != ENXIO) { 1314 if ((flags & MNT_FORCE) && 1315 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1316 if (mp->mnt_vnodecovered != NULL) 1317 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1318 if (rootvnode == NULL) { 1319 rootvnode = fsrootvp; 1320 vref(rootvnode); 1321 } 1322 vput(fsrootvp); 1323 } 1324 MNT_ILOCK(mp); 1325 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1326 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1327 MNT_IUNLOCK(mp); 1328 (void) vfs_allocate_syncvnode(mp); 1329 MNT_ILOCK(mp); 1330 } 1331 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1332 mp->mnt_flag |= async_flag; 1333 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1334 mp->mnt_kern_flag |= MNTK_ASYNC; 1335 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1336 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1337 wakeup(mp); 1338 } 1339 MNT_IUNLOCK(mp); 1340 if (coveredvp) 1341 VOP_UNLOCK(coveredvp, 0); 1342 return (error); 1343 } 1344 mtx_lock(&mountlist_mtx); 1345 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1346 mtx_unlock(&mountlist_mtx); 1347 if (coveredvp != NULL) { 1348 coveredvp->v_mountedhere = NULL; 1349 vput(coveredvp); 1350 } 1351 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1352 vfs_mount_destroy(mp); 1353 return (0); 1354 } 1355 1356 /* 1357 * --------------------------------------------------------------------- 1358 * Mounting of root filesystem 1359 * 1360 */ 1361 1362 struct root_hold_token { 1363 const char *who; 1364 LIST_ENTRY(root_hold_token) list; 1365 }; 1366 1367 static LIST_HEAD(, root_hold_token) root_holds = 1368 LIST_HEAD_INITIALIZER(root_holds); 1369 1370 static int root_mount_complete; 1371 1372 /* 1373 * Hold root mount. 1374 */ 1375 struct root_hold_token * 1376 root_mount_hold(const char *identifier) 1377 { 1378 struct root_hold_token *h; 1379 1380 if (root_mounted()) 1381 return (NULL); 1382 1383 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1384 h->who = identifier; 1385 mtx_lock(&mountlist_mtx); 1386 LIST_INSERT_HEAD(&root_holds, h, list); 1387 mtx_unlock(&mountlist_mtx); 1388 return (h); 1389 } 1390 1391 /* 1392 * Release root mount. 1393 */ 1394 void 1395 root_mount_rel(struct root_hold_token *h) 1396 { 1397 1398 if (h == NULL) 1399 return; 1400 mtx_lock(&mountlist_mtx); 1401 LIST_REMOVE(h, list); 1402 wakeup(&root_holds); 1403 mtx_unlock(&mountlist_mtx); 1404 free(h, M_DEVBUF); 1405 } 1406 1407 /* 1408 * Wait for all subsystems to release root mount. 1409 */ 1410 static void 1411 root_mount_prepare(void) 1412 { 1413 struct root_hold_token *h; 1414 struct timeval lastfail; 1415 int curfail = 0; 1416 1417 for (;;) { 1418 DROP_GIANT(); 1419 g_waitidle(); 1420 PICKUP_GIANT(); 1421 mtx_lock(&mountlist_mtx); 1422 if (LIST_EMPTY(&root_holds)) { 1423 mtx_unlock(&mountlist_mtx); 1424 break; 1425 } 1426 if (ppsratecheck(&lastfail, &curfail, 1)) { 1427 printf("Root mount waiting for:"); 1428 LIST_FOREACH(h, &root_holds, list) 1429 printf(" %s", h->who); 1430 printf("\n"); 1431 } 1432 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1433 hz); 1434 } 1435 } 1436 1437 /* 1438 * Root was mounted, share the good news. 1439 */ 1440 static void 1441 root_mount_done(void) 1442 { 1443 1444 /* Keep prison0's root in sync with the global rootvnode. */ 1445 mtx_lock(&prison0.pr_mtx); 1446 prison0.pr_root = rootvnode; 1447 vref(prison0.pr_root); 1448 mtx_unlock(&prison0.pr_mtx); 1449 /* 1450 * Use a mutex to prevent the wakeup being missed and waiting for 1451 * an extra 1 second sleep. 1452 */ 1453 mtx_lock(&mountlist_mtx); 1454 root_mount_complete = 1; 1455 wakeup(&root_mount_complete); 1456 mtx_unlock(&mountlist_mtx); 1457 } 1458 1459 /* 1460 * Return true if root is already mounted. 1461 */ 1462 int 1463 root_mounted(void) 1464 { 1465 1466 /* No mutex is acquired here because int stores are atomic. */ 1467 return (root_mount_complete); 1468 } 1469 1470 /* 1471 * Wait until root is mounted. 1472 */ 1473 void 1474 root_mount_wait(void) 1475 { 1476 1477 /* 1478 * Panic on an obvious deadlock - the function can't be called from 1479 * a thread which is doing the whole SYSINIT stuff. 1480 */ 1481 KASSERT(curthread->td_proc->p_pid != 0, 1482 ("root_mount_wait: cannot be called from the swapper thread")); 1483 mtx_lock(&mountlist_mtx); 1484 while (!root_mount_complete) { 1485 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1486 hz); 1487 } 1488 mtx_unlock(&mountlist_mtx); 1489 } 1490 1491 static void 1492 set_rootvnode() 1493 { 1494 struct proc *p; 1495 1496 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode)) 1497 panic("Cannot find root vnode"); 1498 1499 VOP_UNLOCK(rootvnode, 0); 1500 1501 p = curthread->td_proc; 1502 FILEDESC_XLOCK(p->p_fd); 1503 1504 if (p->p_fd->fd_cdir != NULL) 1505 vrele(p->p_fd->fd_cdir); 1506 p->p_fd->fd_cdir = rootvnode; 1507 VREF(rootvnode); 1508 1509 if (p->p_fd->fd_rdir != NULL) 1510 vrele(p->p_fd->fd_rdir); 1511 p->p_fd->fd_rdir = rootvnode; 1512 VREF(rootvnode); 1513 1514 FILEDESC_XUNLOCK(p->p_fd); 1515 1516 EVENTHANDLER_INVOKE(mountroot); 1517 } 1518 1519 /* 1520 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1521 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1522 */ 1523 1524 static void 1525 devfs_first(void) 1526 { 1527 struct thread *td = curthread; 1528 struct vfsoptlist *opts; 1529 struct vfsconf *vfsp; 1530 struct mount *mp = NULL; 1531 int error; 1532 1533 vfsp = vfs_byname("devfs"); 1534 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1535 if (vfsp == NULL) 1536 return; 1537 1538 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred); 1539 1540 error = VFS_MOUNT(mp); 1541 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1542 if (error) 1543 return; 1544 1545 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1546 TAILQ_INIT(opts); 1547 mp->mnt_opt = opts; 1548 1549 mtx_lock(&mountlist_mtx); 1550 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1551 mtx_unlock(&mountlist_mtx); 1552 1553 set_rootvnode(); 1554 1555 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1556 if (error) 1557 printf("kern_symlink /dev -> / returns %d\n", error); 1558 } 1559 1560 /* 1561 * Surgically move our devfs to be mounted on /dev. 1562 */ 1563 1564 static void 1565 devfs_fixup(struct thread *td) 1566 { 1567 struct nameidata nd; 1568 int error; 1569 struct vnode *vp, *dvp; 1570 struct mount *mp; 1571 1572 /* Remove our devfs mount from the mountlist and purge the cache */ 1573 mtx_lock(&mountlist_mtx); 1574 mp = TAILQ_FIRST(&mountlist); 1575 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1576 mtx_unlock(&mountlist_mtx); 1577 cache_purgevfs(mp); 1578 1579 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp); 1580 VI_LOCK(dvp); 1581 dvp->v_iflag &= ~VI_MOUNT; 1582 VI_UNLOCK(dvp); 1583 dvp->v_mountedhere = NULL; 1584 1585 /* Set up the real rootvnode, and purge the cache */ 1586 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1587 set_rootvnode(); 1588 cache_purgevfs(rootvnode->v_mount); 1589 1590 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1591 error = namei(&nd); 1592 if (error) { 1593 printf("Lookup of /dev for devfs, error: %d\n", error); 1594 return; 1595 } 1596 NDFREE(&nd, NDF_ONLY_PNBUF); 1597 vp = nd.ni_vp; 1598 if (vp->v_type != VDIR) { 1599 vput(vp); 1600 } 1601 error = vinvalbuf(vp, V_SAVE, 0, 0); 1602 if (error) { 1603 vput(vp); 1604 } 1605 cache_purge(vp); 1606 mp->mnt_vnodecovered = vp; 1607 vp->v_mountedhere = mp; 1608 mtx_lock(&mountlist_mtx); 1609 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1610 mtx_unlock(&mountlist_mtx); 1611 VOP_UNLOCK(vp, 0); 1612 vput(dvp); 1613 vfs_unbusy(mp); 1614 1615 /* Unlink the no longer needed /dev/dev -> / symlink */ 1616 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1617 } 1618 1619 /* 1620 * Report errors during filesystem mounting. 1621 */ 1622 void 1623 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1624 { 1625 struct vfsoptlist *moptlist = mp->mnt_optnew; 1626 va_list ap; 1627 int error, len; 1628 char *errmsg; 1629 1630 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1631 if (error || errmsg == NULL || len <= 0) 1632 return; 1633 1634 va_start(ap, fmt); 1635 vsnprintf(errmsg, (size_t)len, fmt, ap); 1636 va_end(ap); 1637 } 1638 1639 void 1640 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1641 { 1642 va_list ap; 1643 int error, len; 1644 char *errmsg; 1645 1646 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1647 if (error || errmsg == NULL || len <= 0) 1648 return; 1649 1650 va_start(ap, fmt); 1651 vsnprintf(errmsg, (size_t)len, fmt, ap); 1652 va_end(ap); 1653 } 1654 1655 /* 1656 * Find and mount the root filesystem 1657 */ 1658 void 1659 vfs_mountroot(void) 1660 { 1661 char *cp, *cpt, *options, *tmpdev; 1662 int error, i, asked = 0; 1663 1664 options = NULL; 1665 1666 root_mount_prepare(); 1667 1668 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1669 NULL, NULL, mount_init, mount_fini, 1670 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1671 devfs_first(); 1672 1673 /* 1674 * We are booted with instructions to prompt for the root filesystem. 1675 */ 1676 if (boothowto & RB_ASKNAME) { 1677 if (!vfs_mountroot_ask()) 1678 goto mounted; 1679 asked = 1; 1680 } 1681 1682 options = getenv("vfs.root.mountfrom.options"); 1683 1684 /* 1685 * The root filesystem information is compiled in, and we are 1686 * booted with instructions to use it. 1687 */ 1688 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1689 if (!vfs_mountroot_try(ctrootdevname, options)) 1690 goto mounted; 1691 ctrootdevname = NULL; 1692 } 1693 1694 /* 1695 * We've been given the generic "use CDROM as root" flag. This is 1696 * necessary because one media may be used in many different 1697 * devices, so we need to search for them. 1698 */ 1699 if (boothowto & RB_CDROM) { 1700 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1701 if (!vfs_mountroot_try(cdrom_rootdevnames[i], options)) 1702 goto mounted; 1703 } 1704 } 1705 1706 /* 1707 * Try to use the value read by the loader from /etc/fstab, or 1708 * supplied via some other means. This is the preferred 1709 * mechanism. 1710 */ 1711 cp = getenv("vfs.root.mountfrom"); 1712 if (cp != NULL) { 1713 cpt = cp; 1714 while ((tmpdev = strsep(&cpt, " \t")) != NULL) { 1715 error = vfs_mountroot_try(tmpdev, options); 1716 if (error == 0) { 1717 freeenv(cp); 1718 goto mounted; 1719 } 1720 } 1721 freeenv(cp); 1722 } 1723 1724 /* 1725 * Try values that may have been computed by code during boot 1726 */ 1727 if (!vfs_mountroot_try(rootdevnames[0], options)) 1728 goto mounted; 1729 if (!vfs_mountroot_try(rootdevnames[1], options)) 1730 goto mounted; 1731 1732 /* 1733 * If we (still) have a compiled-in default, try it. 1734 */ 1735 if (ctrootdevname != NULL) 1736 if (!vfs_mountroot_try(ctrootdevname, options)) 1737 goto mounted; 1738 /* 1739 * Everything so far has failed, prompt on the console if we haven't 1740 * already tried that. 1741 */ 1742 if (!asked) 1743 if (!vfs_mountroot_ask()) 1744 goto mounted; 1745 1746 panic("Root mount failed, startup aborted."); 1747 1748 mounted: 1749 root_mount_done(); 1750 freeenv(options); 1751 } 1752 1753 static struct mntarg * 1754 parse_mountroot_options(struct mntarg *ma, const char *options) 1755 { 1756 char *p; 1757 char *name, *name_arg; 1758 char *val, *val_arg; 1759 char *opts; 1760 1761 if (options == NULL || options[0] == '\0') 1762 return (ma); 1763 1764 p = opts = strdup(options, M_MOUNT); 1765 if (opts == NULL) { 1766 return (ma); 1767 } 1768 1769 while((name = strsep(&p, ",")) != NULL) { 1770 if (name[0] == '\0') 1771 break; 1772 1773 val = strchr(name, '='); 1774 if (val != NULL) { 1775 *val = '\0'; 1776 ++val; 1777 } 1778 if( strcmp(name, "rw") == 0 || 1779 strcmp(name, "noro") == 0) { 1780 /* 1781 * The first time we mount the root file system, 1782 * we need to mount 'ro', so We need to ignore 1783 * 'rw' and 'noro' mount options. 1784 */ 1785 continue; 1786 } 1787 name_arg = strdup(name, M_MOUNT); 1788 val_arg = NULL; 1789 if (val != NULL) 1790 val_arg = strdup(val, M_MOUNT); 1791 1792 ma = mount_arg(ma, name_arg, val_arg, 1793 (val_arg != NULL ? -1 : 0)); 1794 } 1795 free(opts, M_MOUNT); 1796 return (ma); 1797 } 1798 1799 /* 1800 * Mount (mountfrom) as the root filesystem. 1801 */ 1802 static int 1803 vfs_mountroot_try(const char *mountfrom, const char *options) 1804 { 1805 struct mount *mp; 1806 struct mntarg *ma; 1807 char *vfsname, *path; 1808 time_t timebase; 1809 int error; 1810 char patt[32]; 1811 char errmsg[255]; 1812 1813 vfsname = NULL; 1814 path = NULL; 1815 mp = NULL; 1816 ma = NULL; 1817 error = EINVAL; 1818 bzero(errmsg, sizeof(errmsg)); 1819 1820 if (mountfrom == NULL) 1821 return (error); /* don't complain */ 1822 printf("Trying to mount root from %s\n", mountfrom); 1823 1824 /* parse vfs name and path */ 1825 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1826 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1827 vfsname[0] = path[0] = 0; 1828 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1829 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1830 goto out; 1831 1832 if (path[0] == '\0') 1833 strcpy(path, ROOTNAME); 1834 1835 ma = mount_arg(ma, "fstype", vfsname, -1); 1836 ma = mount_arg(ma, "fspath", "/", -1); 1837 ma = mount_arg(ma, "from", path, -1); 1838 ma = mount_arg(ma, "errmsg", errmsg, sizeof(errmsg)); 1839 ma = mount_arg(ma, "ro", NULL, 0); 1840 ma = parse_mountroot_options(ma, options); 1841 error = kernel_mount(ma, MNT_ROOTFS); 1842 1843 if (error == 0) { 1844 /* 1845 * We mount devfs prior to mounting the / FS, so the first 1846 * entry will typically be devfs. 1847 */ 1848 mp = TAILQ_FIRST(&mountlist); 1849 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1850 1851 /* 1852 * Iterate over all currently mounted file systems and use 1853 * the time stamp found to check and/or initialize the RTC. 1854 * Typically devfs has no time stamp and the only other FS 1855 * is the actual / FS. 1856 * Call inittodr() only once and pass it the largest of the 1857 * timestamps we encounter. 1858 */ 1859 timebase = 0; 1860 do { 1861 if (mp->mnt_time > timebase) 1862 timebase = mp->mnt_time; 1863 mp = TAILQ_NEXT(mp, mnt_list); 1864 } while (mp != NULL); 1865 inittodr(timebase); 1866 1867 devfs_fixup(curthread); 1868 } 1869 1870 if (error != 0 ) { 1871 printf("ROOT MOUNT ERROR: %s\n", errmsg); 1872 printf("If you have invalid mount options, reboot, and "); 1873 printf("first try the following from\n"); 1874 printf("the loader prompt:\n\n"); 1875 printf(" set vfs.root.mountfrom.options=rw\n\n"); 1876 printf("and then remove invalid mount options from "); 1877 printf("/etc/fstab.\n\n"); 1878 } 1879 out: 1880 free(path, M_MOUNT); 1881 free(vfsname, M_MOUNT); 1882 return (error); 1883 } 1884 1885 /* 1886 * --------------------------------------------------------------------- 1887 * Interactive root filesystem selection code. 1888 */ 1889 1890 static int 1891 vfs_mountroot_ask(void) 1892 { 1893 char name[128]; 1894 char *mountfrom; 1895 char *options; 1896 1897 for(;;) { 1898 printf("Loader variables:\n"); 1899 printf("vfs.root.mountfrom="); 1900 mountfrom = getenv("vfs.root.mountfrom"); 1901 if (mountfrom != NULL) { 1902 printf("%s", mountfrom); 1903 } 1904 printf("\n"); 1905 printf("vfs.root.mountfrom.options="); 1906 options = getenv("vfs.root.mountfrom.options"); 1907 if (options != NULL) { 1908 printf("%s", options); 1909 } 1910 printf("\n"); 1911 freeenv(mountfrom); 1912 freeenv(options); 1913 printf("\nManual root filesystem specification:\n"); 1914 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1915 printf(" eg. ufs:/dev/da0s1a\n"); 1916 printf(" eg. cd9660:/dev/acd0\n"); 1917 printf(" This is equivalent to: "); 1918 printf("mount -t cd9660 /dev/acd0 /\n"); 1919 printf("\n"); 1920 printf(" ? List valid disk boot devices\n"); 1921 printf(" <empty line> Abort manual input\n"); 1922 printf("\nmountroot> "); 1923 gets(name, sizeof(name), 1); 1924 if (name[0] == '\0') 1925 return (1); 1926 if (name[0] == '?') { 1927 printf("\nList of GEOM managed disk devices:\n "); 1928 g_dev_print(); 1929 continue; 1930 } 1931 if (!vfs_mountroot_try(name, NULL)) 1932 return (0); 1933 } 1934 } 1935 1936 /* 1937 * --------------------------------------------------------------------- 1938 * Functions for querying mount options/arguments from filesystems. 1939 */ 1940 1941 /* 1942 * Check that no unknown options are given 1943 */ 1944 int 1945 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1946 { 1947 struct vfsopt *opt; 1948 char errmsg[255]; 1949 const char **t, *p, *q; 1950 int ret = 0; 1951 1952 TAILQ_FOREACH(opt, opts, link) { 1953 p = opt->name; 1954 q = NULL; 1955 if (p[0] == 'n' && p[1] == 'o') 1956 q = p + 2; 1957 for(t = global_opts; *t != NULL; t++) { 1958 if (strcmp(*t, p) == 0) 1959 break; 1960 if (q != NULL) { 1961 if (strcmp(*t, q) == 0) 1962 break; 1963 } 1964 } 1965 if (*t != NULL) 1966 continue; 1967 for(t = legal; *t != NULL; t++) { 1968 if (strcmp(*t, p) == 0) 1969 break; 1970 if (q != NULL) { 1971 if (strcmp(*t, q) == 0) 1972 break; 1973 } 1974 } 1975 if (*t != NULL) 1976 continue; 1977 snprintf(errmsg, sizeof(errmsg), 1978 "mount option <%s> is unknown", p); 1979 printf("%s\n", errmsg); 1980 ret = EINVAL; 1981 } 1982 if (ret != 0) { 1983 TAILQ_FOREACH(opt, opts, link) { 1984 if (strcmp(opt->name, "errmsg") == 0) { 1985 strncpy((char *)opt->value, errmsg, opt->len); 1986 } 1987 } 1988 } 1989 return (ret); 1990 } 1991 1992 /* 1993 * Get a mount option by its name. 1994 * 1995 * Return 0 if the option was found, ENOENT otherwise. 1996 * If len is non-NULL it will be filled with the length 1997 * of the option. If buf is non-NULL, it will be filled 1998 * with the address of the option. 1999 */ 2000 int 2001 vfs_getopt(opts, name, buf, len) 2002 struct vfsoptlist *opts; 2003 const char *name; 2004 void **buf; 2005 int *len; 2006 { 2007 struct vfsopt *opt; 2008 2009 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2010 2011 TAILQ_FOREACH(opt, opts, link) { 2012 if (strcmp(name, opt->name) == 0) { 2013 opt->seen = 1; 2014 if (len != NULL) 2015 *len = opt->len; 2016 if (buf != NULL) 2017 *buf = opt->value; 2018 return (0); 2019 } 2020 } 2021 return (ENOENT); 2022 } 2023 2024 int 2025 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 2026 { 2027 struct vfsopt *opt; 2028 2029 if (opts == NULL) 2030 return (-1); 2031 2032 TAILQ_FOREACH(opt, opts, link) { 2033 if (strcmp(name, opt->name) == 0) { 2034 opt->seen = 1; 2035 return (opt->pos); 2036 } 2037 } 2038 return (-1); 2039 } 2040 2041 char * 2042 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 2043 { 2044 struct vfsopt *opt; 2045 2046 *error = 0; 2047 TAILQ_FOREACH(opt, opts, link) { 2048 if (strcmp(name, opt->name) != 0) 2049 continue; 2050 opt->seen = 1; 2051 if (opt->len == 0 || 2052 ((char *)opt->value)[opt->len - 1] != '\0') { 2053 *error = EINVAL; 2054 return (NULL); 2055 } 2056 return (opt->value); 2057 } 2058 *error = ENOENT; 2059 return (NULL); 2060 } 2061 2062 int 2063 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 2064 { 2065 struct vfsopt *opt; 2066 2067 TAILQ_FOREACH(opt, opts, link) { 2068 if (strcmp(name, opt->name) == 0) { 2069 opt->seen = 1; 2070 if (w != NULL) 2071 *w |= val; 2072 return (1); 2073 } 2074 } 2075 if (w != NULL) 2076 *w &= ~val; 2077 return (0); 2078 } 2079 2080 int 2081 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 2082 { 2083 va_list ap; 2084 struct vfsopt *opt; 2085 int ret; 2086 2087 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2088 2089 TAILQ_FOREACH(opt, opts, link) { 2090 if (strcmp(name, opt->name) != 0) 2091 continue; 2092 opt->seen = 1; 2093 if (opt->len == 0 || opt->value == NULL) 2094 return (0); 2095 if (((char *)opt->value)[opt->len - 1] != '\0') 2096 return (0); 2097 va_start(ap, fmt); 2098 ret = vsscanf(opt->value, fmt, ap); 2099 va_end(ap); 2100 return (ret); 2101 } 2102 return (0); 2103 } 2104 2105 int 2106 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 2107 { 2108 struct vfsopt *opt; 2109 2110 TAILQ_FOREACH(opt, opts, link) { 2111 if (strcmp(name, opt->name) != 0) 2112 continue; 2113 opt->seen = 1; 2114 if (opt->value == NULL) 2115 opt->len = len; 2116 else { 2117 if (opt->len != len) 2118 return (EINVAL); 2119 bcopy(value, opt->value, len); 2120 } 2121 return (0); 2122 } 2123 return (ENOENT); 2124 } 2125 2126 int 2127 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 2128 { 2129 struct vfsopt *opt; 2130 2131 TAILQ_FOREACH(opt, opts, link) { 2132 if (strcmp(name, opt->name) != 0) 2133 continue; 2134 opt->seen = 1; 2135 if (opt->value == NULL) 2136 opt->len = len; 2137 else { 2138 if (opt->len < len) 2139 return (EINVAL); 2140 opt->len = len; 2141 bcopy(value, opt->value, len); 2142 } 2143 return (0); 2144 } 2145 return (ENOENT); 2146 } 2147 2148 int 2149 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2150 { 2151 struct vfsopt *opt; 2152 2153 TAILQ_FOREACH(opt, opts, link) { 2154 if (strcmp(name, opt->name) != 0) 2155 continue; 2156 opt->seen = 1; 2157 if (opt->value == NULL) 2158 opt->len = strlen(value) + 1; 2159 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2160 return (EINVAL); 2161 return (0); 2162 } 2163 return (ENOENT); 2164 } 2165 2166 /* 2167 * Find and copy a mount option. 2168 * 2169 * The size of the buffer has to be specified 2170 * in len, if it is not the same length as the 2171 * mount option, EINVAL is returned. 2172 * Returns ENOENT if the option is not found. 2173 */ 2174 int 2175 vfs_copyopt(opts, name, dest, len) 2176 struct vfsoptlist *opts; 2177 const char *name; 2178 void *dest; 2179 int len; 2180 { 2181 struct vfsopt *opt; 2182 2183 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2184 2185 TAILQ_FOREACH(opt, opts, link) { 2186 if (strcmp(name, opt->name) == 0) { 2187 opt->seen = 1; 2188 if (len != opt->len) 2189 return (EINVAL); 2190 bcopy(opt->value, dest, opt->len); 2191 return (0); 2192 } 2193 } 2194 return (ENOENT); 2195 } 2196 2197 /* 2198 * This is a helper function for filesystems to traverse their 2199 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 2200 */ 2201 2202 struct vnode * 2203 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 2204 { 2205 struct vnode *vp; 2206 2207 mtx_assert(MNT_MTX(mp), MA_OWNED); 2208 2209 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2210 if ((*mvp)->v_yield++ == 500) { 2211 MNT_IUNLOCK(mp); 2212 (*mvp)->v_yield = 0; 2213 uio_yield(); 2214 MNT_ILOCK(mp); 2215 } 2216 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 2217 while (vp != NULL && vp->v_type == VMARKER) 2218 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2219 2220 /* Check if we are done */ 2221 if (vp == NULL) { 2222 __mnt_vnode_markerfree(mvp, mp); 2223 return (NULL); 2224 } 2225 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2226 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2227 return (vp); 2228 } 2229 2230 struct vnode * 2231 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2232 { 2233 struct vnode *vp; 2234 2235 mtx_assert(MNT_MTX(mp), MA_OWNED); 2236 2237 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2238 while (vp != NULL && vp->v_type == VMARKER) 2239 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2240 2241 /* Check if we are done */ 2242 if (vp == NULL) { 2243 *mvp = NULL; 2244 return (NULL); 2245 } 2246 MNT_REF(mp); 2247 MNT_IUNLOCK(mp); 2248 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2249 M_VNODE_MARKER, 2250 M_WAITOK | M_ZERO); 2251 MNT_ILOCK(mp); 2252 (*mvp)->v_type = VMARKER; 2253 2254 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2255 while (vp != NULL && vp->v_type == VMARKER) 2256 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2257 2258 /* Check if we are done */ 2259 if (vp == NULL) { 2260 MNT_IUNLOCK(mp); 2261 free(*mvp, M_VNODE_MARKER); 2262 MNT_ILOCK(mp); 2263 *mvp = NULL; 2264 MNT_REL(mp); 2265 return (NULL); 2266 } 2267 (*mvp)->v_mount = mp; 2268 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2269 return (vp); 2270 } 2271 2272 2273 void 2274 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2275 { 2276 2277 if (*mvp == NULL) 2278 return; 2279 2280 mtx_assert(MNT_MTX(mp), MA_OWNED); 2281 2282 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2283 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2284 MNT_IUNLOCK(mp); 2285 free(*mvp, M_VNODE_MARKER); 2286 MNT_ILOCK(mp); 2287 *mvp = NULL; 2288 MNT_REL(mp); 2289 } 2290 2291 2292 int 2293 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2294 { 2295 int error; 2296 2297 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat); 2298 if (sbp != &mp->mnt_stat) 2299 *sbp = mp->mnt_stat; 2300 return (error); 2301 } 2302 2303 void 2304 vfs_mountedfrom(struct mount *mp, const char *from) 2305 { 2306 2307 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2308 strlcpy(mp->mnt_stat.f_mntfromname, from, 2309 sizeof mp->mnt_stat.f_mntfromname); 2310 } 2311 2312 /* 2313 * --------------------------------------------------------------------- 2314 * This is the api for building mount args and mounting filesystems from 2315 * inside the kernel. 2316 * 2317 * The API works by accumulation of individual args. First error is 2318 * latched. 2319 * 2320 * XXX: should be documented in new manpage kernel_mount(9) 2321 */ 2322 2323 /* A memory allocation which must be freed when we are done */ 2324 struct mntaarg { 2325 SLIST_ENTRY(mntaarg) next; 2326 }; 2327 2328 /* The header for the mount arguments */ 2329 struct mntarg { 2330 struct iovec *v; 2331 int len; 2332 int error; 2333 SLIST_HEAD(, mntaarg) list; 2334 }; 2335 2336 /* 2337 * Add a boolean argument. 2338 * 2339 * flag is the boolean value. 2340 * name must start with "no". 2341 */ 2342 struct mntarg * 2343 mount_argb(struct mntarg *ma, int flag, const char *name) 2344 { 2345 2346 KASSERT(name[0] == 'n' && name[1] == 'o', 2347 ("mount_argb(...,%s): name must start with 'no'", name)); 2348 2349 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2350 } 2351 2352 /* 2353 * Add an argument printf style 2354 */ 2355 struct mntarg * 2356 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2357 { 2358 va_list ap; 2359 struct mntaarg *maa; 2360 struct sbuf *sb; 2361 int len; 2362 2363 if (ma == NULL) { 2364 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2365 SLIST_INIT(&ma->list); 2366 } 2367 if (ma->error) 2368 return (ma); 2369 2370 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2371 M_MOUNT, M_WAITOK); 2372 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2373 ma->v[ma->len].iov_len = strlen(name) + 1; 2374 ma->len++; 2375 2376 sb = sbuf_new_auto(); 2377 va_start(ap, fmt); 2378 sbuf_vprintf(sb, fmt, ap); 2379 va_end(ap); 2380 sbuf_finish(sb); 2381 len = sbuf_len(sb) + 1; 2382 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2383 SLIST_INSERT_HEAD(&ma->list, maa, next); 2384 bcopy(sbuf_data(sb), maa + 1, len); 2385 sbuf_delete(sb); 2386 2387 ma->v[ma->len].iov_base = maa + 1; 2388 ma->v[ma->len].iov_len = len; 2389 ma->len++; 2390 2391 return (ma); 2392 } 2393 2394 /* 2395 * Add an argument which is a userland string. 2396 */ 2397 struct mntarg * 2398 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2399 { 2400 struct mntaarg *maa; 2401 char *tbuf; 2402 2403 if (val == NULL) 2404 return (ma); 2405 if (ma == NULL) { 2406 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2407 SLIST_INIT(&ma->list); 2408 } 2409 if (ma->error) 2410 return (ma); 2411 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2412 SLIST_INSERT_HEAD(&ma->list, maa, next); 2413 tbuf = (void *)(maa + 1); 2414 ma->error = copyinstr(val, tbuf, len, NULL); 2415 return (mount_arg(ma, name, tbuf, -1)); 2416 } 2417 2418 /* 2419 * Plain argument. 2420 * 2421 * If length is -1, treat value as a C string. 2422 */ 2423 struct mntarg * 2424 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2425 { 2426 2427 if (ma == NULL) { 2428 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2429 SLIST_INIT(&ma->list); 2430 } 2431 if (ma->error) 2432 return (ma); 2433 2434 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2435 M_MOUNT, M_WAITOK); 2436 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2437 ma->v[ma->len].iov_len = strlen(name) + 1; 2438 ma->len++; 2439 2440 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2441 if (len < 0) 2442 ma->v[ma->len].iov_len = strlen(val) + 1; 2443 else 2444 ma->v[ma->len].iov_len = len; 2445 ma->len++; 2446 return (ma); 2447 } 2448 2449 /* 2450 * Free a mntarg structure 2451 */ 2452 static void 2453 free_mntarg(struct mntarg *ma) 2454 { 2455 struct mntaarg *maa; 2456 2457 while (!SLIST_EMPTY(&ma->list)) { 2458 maa = SLIST_FIRST(&ma->list); 2459 SLIST_REMOVE_HEAD(&ma->list, next); 2460 free(maa, M_MOUNT); 2461 } 2462 free(ma->v, M_MOUNT); 2463 free(ma, M_MOUNT); 2464 } 2465 2466 /* 2467 * Mount a filesystem 2468 */ 2469 int 2470 kernel_mount(struct mntarg *ma, int flags) 2471 { 2472 struct uio auio; 2473 int error; 2474 2475 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2476 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2477 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2478 2479 auio.uio_iov = ma->v; 2480 auio.uio_iovcnt = ma->len; 2481 auio.uio_segflg = UIO_SYSSPACE; 2482 2483 error = ma->error; 2484 if (!error) 2485 error = vfs_donmount(curthread, flags, &auio); 2486 free_mntarg(ma); 2487 return (error); 2488 } 2489 2490 /* 2491 * A printflike function to mount a filesystem. 2492 */ 2493 int 2494 kernel_vmount(int flags, ...) 2495 { 2496 struct mntarg *ma = NULL; 2497 va_list ap; 2498 const char *cp; 2499 const void *vp; 2500 int error; 2501 2502 va_start(ap, flags); 2503 for (;;) { 2504 cp = va_arg(ap, const char *); 2505 if (cp == NULL) 2506 break; 2507 vp = va_arg(ap, const void *); 2508 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2509 } 2510 va_end(ap); 2511 2512 error = kernel_mount(ma, flags); 2513 return (error); 2514 } 2515 2516 void 2517 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 2518 { 2519 2520 bcopy(oexp, exp, sizeof(*oexp)); 2521 exp->ex_numsecflavors = 0; 2522 }
Cache object: 4572185335b7d4f4c76a6d56f6a9ed21
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