1 /*- 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1999 Michael Smith 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/conf.h> 42 #include <sys/clock.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 #include "opt_ddb.h" 72 #include "opt_mac.h" 73 74 #ifdef DDB 75 #include <ddb/ddb.h> 76 #endif 77 78 #define ROOTNAME "root_device" 79 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 80 81 static int vfs_domount(struct thread *td, const char *fstype, 82 char *fspath, int fsflags, void *fsdata); 83 static int vfs_mountroot_ask(void); 84 static int vfs_mountroot_try(const char *mountfrom); 85 static int vfs_donmount(struct thread *td, int fsflags, 86 struct uio *fsoptions); 87 static void free_mntarg(struct mntarg *ma); 88 static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 89 90 static int usermount = 0; 91 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 92 "Unprivileged users may mount and unmount file systems"); 93 94 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 95 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 96 static uma_zone_t mount_zone; 97 98 /* List of mounted filesystems. */ 99 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 100 101 /* For any iteration/modification of mountlist */ 102 struct mtx mountlist_mtx; 103 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 104 105 TAILQ_HEAD(vfsoptlist, vfsopt); 106 struct vfsopt { 107 TAILQ_ENTRY(vfsopt) link; 108 char *name; 109 void *value; 110 int len; 111 }; 112 113 /* 114 * The vnode of the system's root (/ in the filesystem, without chroot 115 * active.) 116 */ 117 struct vnode *rootvnode; 118 119 /* 120 * The root filesystem is detailed in the kernel environment variable 121 * vfs.root.mountfrom, which is expected to be in the general format 122 * 123 * <vfsname>:[<path>] 124 * vfsname := the name of a VFS known to the kernel and capable 125 * of being mounted as root 126 * path := disk device name or other data used by the filesystem 127 * to locate its physical store 128 */ 129 130 /* 131 * Global opts, taken by all filesystems 132 */ 133 static const char *global_opts[] = { 134 "errmsg", 135 "fstype", 136 "fspath", 137 "rdonly", 138 "ro", 139 "rw", 140 "nosuid", 141 "noexec", 142 "update", 143 NULL 144 }; 145 146 /* 147 * The root specifiers we will try if RB_CDROM is specified. 148 */ 149 static char *cdrom_rootdevnames[] = { 150 "cd9660:cd0", 151 "cd9660:acd0", 152 NULL 153 }; 154 155 /* legacy find-root code */ 156 char *rootdevnames[2] = {NULL, NULL}; 157 #ifndef ROOTDEVNAME 158 # define ROOTDEVNAME NULL 159 #endif 160 static const char *ctrootdevname = ROOTDEVNAME; 161 162 /* 163 * --------------------------------------------------------------------- 164 * Functions for building and sanitizing the mount options 165 */ 166 167 /* Remove one mount option. */ 168 static void 169 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 170 { 171 172 TAILQ_REMOVE(opts, opt, link); 173 free(opt->name, M_MOUNT); 174 if (opt->value != NULL) 175 free(opt->value, M_MOUNT); 176 #ifdef INVARIANTS 177 else if (opt->len != 0) 178 panic("%s: mount option with NULL value but length != 0", 179 __func__); 180 #endif 181 free(opt, M_MOUNT); 182 } 183 184 /* Release all resources related to the mount options. */ 185 void 186 vfs_freeopts(struct vfsoptlist *opts) 187 { 188 struct vfsopt *opt; 189 190 while (!TAILQ_EMPTY(opts)) { 191 opt = TAILQ_FIRST(opts); 192 vfs_freeopt(opts, opt); 193 } 194 free(opts, M_MOUNT); 195 } 196 197 void 198 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 199 { 200 struct vfsopt *opt, *temp; 201 202 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 203 if (strcmp(opt->name, name) == 0) 204 vfs_freeopt(opts, opt); 205 } 206 } 207 208 /* 209 * Check if options are equal (with or without the "no" prefix). 210 */ 211 static int 212 vfs_equalopts(const char *opt1, const char *opt2) 213 { 214 215 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 216 if (strcmp(opt1, opt2) == 0) 217 return (1); 218 /* "noopt" vs. "opt" */ 219 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 220 return (1); 221 /* "opt" vs. "noopt" */ 222 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 223 return (1); 224 return (0); 225 } 226 227 /* 228 * If a mount option is specified several times, 229 * (with or without the "no" prefix) only keep 230 * the last occurence of it. 231 */ 232 static void 233 vfs_sanitizeopts(struct vfsoptlist *opts) 234 { 235 struct vfsopt *opt, *opt2, *tmp; 236 237 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 238 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 239 while (opt2 != NULL) { 240 if (vfs_equalopts(opt->name, opt2->name)) { 241 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 242 vfs_freeopt(opts, opt2); 243 opt2 = tmp; 244 } else { 245 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 246 } 247 } 248 } 249 } 250 251 /* 252 * Build a linked list of mount options from a struct uio. 253 */ 254 static int 255 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 256 { 257 struct vfsoptlist *opts; 258 struct vfsopt *opt; 259 size_t memused; 260 unsigned int i, iovcnt; 261 int error, namelen, optlen; 262 263 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 264 TAILQ_INIT(opts); 265 memused = 0; 266 iovcnt = auio->uio_iovcnt; 267 for (i = 0; i < iovcnt; i += 2) { 268 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 269 namelen = auio->uio_iov[i].iov_len; 270 optlen = auio->uio_iov[i + 1].iov_len; 271 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 272 opt->value = NULL; 273 opt->len = 0; 274 275 /* 276 * Do this early, so jumps to "bad" will free the current 277 * option. 278 */ 279 TAILQ_INSERT_TAIL(opts, opt, link); 280 memused += sizeof(struct vfsopt) + optlen + namelen; 281 282 /* 283 * Avoid consuming too much memory, and attempts to overflow 284 * memused. 285 */ 286 if (memused > VFS_MOUNTARG_SIZE_MAX || 287 optlen > VFS_MOUNTARG_SIZE_MAX || 288 namelen > VFS_MOUNTARG_SIZE_MAX) { 289 error = EINVAL; 290 goto bad; 291 } 292 293 if (auio->uio_segflg == UIO_SYSSPACE) { 294 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 295 } else { 296 error = copyin(auio->uio_iov[i].iov_base, opt->name, 297 namelen); 298 if (error) 299 goto bad; 300 } 301 /* Ensure names are null-terminated strings. */ 302 if (opt->name[namelen - 1] != '\0') { 303 error = EINVAL; 304 goto bad; 305 } 306 if (optlen != 0) { 307 opt->len = optlen; 308 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 309 if (auio->uio_segflg == UIO_SYSSPACE) { 310 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 311 optlen); 312 } else { 313 error = copyin(auio->uio_iov[i + 1].iov_base, 314 opt->value, optlen); 315 if (error) 316 goto bad; 317 } 318 } 319 } 320 vfs_sanitizeopts(opts); 321 *options = opts; 322 return (0); 323 bad: 324 vfs_freeopts(opts); 325 return (error); 326 } 327 328 /* 329 * Merge the old mount options with the new ones passed 330 * in the MNT_UPDATE case. 331 */ 332 static void 333 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 334 { 335 struct vfsopt *opt, *opt2, *new; 336 337 TAILQ_FOREACH(opt, opts, link) { 338 /* 339 * Check that this option hasn't been redefined 340 * nor cancelled with a "no" mount option. 341 */ 342 opt2 = TAILQ_FIRST(toopts); 343 while (opt2 != NULL) { 344 if (strcmp(opt2->name, opt->name) == 0) 345 goto next; 346 if (strncmp(opt2->name, "no", 2) == 0 && 347 strcmp(opt2->name + 2, opt->name) == 0) { 348 vfs_freeopt(toopts, opt2); 349 goto next; 350 } 351 opt2 = TAILQ_NEXT(opt2, link); 352 } 353 /* We want this option, duplicate it. */ 354 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 355 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 356 strcpy(new->name, opt->name); 357 if (opt->len != 0) { 358 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 359 bcopy(opt->value, new->value, opt->len); 360 } else { 361 new->value = NULL; 362 } 363 new->len = opt->len; 364 TAILQ_INSERT_TAIL(toopts, new, link); 365 next: 366 continue; 367 } 368 } 369 370 /* 371 * Mount a filesystem. 372 */ 373 int 374 nmount(td, uap) 375 struct thread *td; 376 struct nmount_args /* { 377 struct iovec *iovp; 378 unsigned int iovcnt; 379 int flags; 380 } */ *uap; 381 { 382 struct uio *auio; 383 struct iovec *iov; 384 unsigned int i; 385 int error; 386 u_int iovcnt; 387 388 AUDIT_ARG(fflags, uap->flags); 389 390 /* 391 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 392 * userspace to set this flag, but we must filter it out if we want 393 * MNT_UPDATE on the root file system to work. 394 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 395 */ 396 uap->flags &= ~MNT_ROOTFS; 397 398 iovcnt = uap->iovcnt; 399 /* 400 * Check that we have an even number of iovec's 401 * and that we have at least two options. 402 */ 403 if ((iovcnt & 1) || (iovcnt < 4)) 404 return (EINVAL); 405 406 error = copyinuio(uap->iovp, iovcnt, &auio); 407 if (error) 408 return (error); 409 iov = auio->uio_iov; 410 for (i = 0; i < iovcnt; i++) { 411 if (iov->iov_len > MMAXOPTIONLEN) { 412 free(auio, M_IOV); 413 return (EINVAL); 414 } 415 iov++; 416 } 417 error = vfs_donmount(td, uap->flags, auio); 418 419 free(auio, M_IOV); 420 return (error); 421 } 422 423 /* 424 * --------------------------------------------------------------------- 425 * Various utility functions 426 */ 427 428 void 429 vfs_ref(struct mount *mp) 430 { 431 432 MNT_ILOCK(mp); 433 MNT_REF(mp); 434 MNT_IUNLOCK(mp); 435 } 436 437 void 438 vfs_rel(struct mount *mp) 439 { 440 441 MNT_ILOCK(mp); 442 MNT_REL(mp); 443 MNT_IUNLOCK(mp); 444 } 445 446 static int 447 mount_init(void *mem, int size, int flags) 448 { 449 struct mount *mp; 450 451 mp = (struct mount *)mem; 452 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 453 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0); 454 return (0); 455 } 456 457 static void 458 mount_fini(void *mem, int size) 459 { 460 struct mount *mp; 461 462 mp = (struct mount *)mem; 463 lockdestroy(&mp->mnt_lock); 464 mtx_destroy(&mp->mnt_mtx); 465 } 466 467 /* 468 * Allocate and initialize the mount point struct. 469 */ 470 struct mount * 471 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 472 const char *fspath, struct thread *td) 473 { 474 struct mount *mp; 475 476 mp = uma_zalloc(mount_zone, M_WAITOK); 477 bzero(&mp->mnt_startzero, 478 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 479 TAILQ_INIT(&mp->mnt_nvnodelist); 480 mp->mnt_nvnodelistsize = 0; 481 mp->mnt_ref = 0; 482 (void) vfs_busy(mp, LK_NOWAIT, 0, td); 483 mp->mnt_op = vfsp->vfc_vfsops; 484 mp->mnt_vfc = vfsp; 485 vfsp->vfc_refcount++; /* XXX Unlocked */ 486 mp->mnt_stat.f_type = vfsp->vfc_typenum; 487 mp->mnt_gen++; 488 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 489 mp->mnt_vnodecovered = vp; 490 mp->mnt_cred = crdup(td->td_ucred); 491 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 492 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 493 mp->mnt_iosize_max = DFLTPHYS; 494 #ifdef MAC 495 mac_mount_init(mp); 496 mac_mount_create(td->td_ucred, mp); 497 #endif 498 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 499 return (mp); 500 } 501 502 /* 503 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 504 */ 505 void 506 vfs_mount_destroy(struct mount *mp) 507 { 508 int i; 509 510 MNT_ILOCK(mp); 511 for (i = 0; mp->mnt_ref && i < 3; i++) 512 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 513 /* 514 * This will always cause a 3 second delay in rebooting due to 515 * refs on the root mountpoint that never go away. Most of these 516 * are held by init which never exits. 517 */ 518 if (i == 3 && (!rebooting || bootverbose)) 519 printf("Mount point %s had %d dangling refs\n", 520 mp->mnt_stat.f_mntonname, mp->mnt_ref); 521 if (mp->mnt_holdcnt != 0) { 522 printf("Waiting for mount point to be unheld\n"); 523 while (mp->mnt_holdcnt != 0) { 524 mp->mnt_holdcntwaiters++; 525 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 526 PZERO, "mntdestroy", 0); 527 mp->mnt_holdcntwaiters--; 528 } 529 printf("mount point unheld\n"); 530 } 531 if (mp->mnt_writeopcount > 0) { 532 printf("Waiting for mount point write ops\n"); 533 while (mp->mnt_writeopcount > 0) { 534 mp->mnt_kern_flag |= MNTK_SUSPEND; 535 msleep(&mp->mnt_writeopcount, 536 MNT_MTX(mp), 537 PZERO, "mntdestroy2", 0); 538 } 539 printf("mount point write ops completed\n"); 540 } 541 if (mp->mnt_secondary_writes > 0) { 542 printf("Waiting for mount point secondary write ops\n"); 543 while (mp->mnt_secondary_writes > 0) { 544 mp->mnt_kern_flag |= MNTK_SUSPEND; 545 msleep(&mp->mnt_secondary_writes, 546 MNT_MTX(mp), 547 PZERO, "mntdestroy3", 0); 548 } 549 printf("mount point secondary write ops completed\n"); 550 } 551 MNT_IUNLOCK(mp); 552 mp->mnt_vfc->vfc_refcount--; 553 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 554 struct vnode *vp; 555 556 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 557 vprint("", vp); 558 panic("unmount: dangling vnode"); 559 } 560 MNT_ILOCK(mp); 561 if (mp->mnt_kern_flag & MNTK_MWAIT) 562 wakeup(mp); 563 if (mp->mnt_writeopcount != 0) 564 panic("vfs_mount_destroy: nonzero writeopcount"); 565 if (mp->mnt_secondary_writes != 0) 566 panic("vfs_mount_destroy: nonzero secondary_writes"); 567 if (mp->mnt_nvnodelistsize != 0) 568 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 569 mp->mnt_writeopcount = -1000; 570 mp->mnt_nvnodelistsize = -1000; 571 mp->mnt_secondary_writes = -1000; 572 MNT_IUNLOCK(mp); 573 #ifdef MAC 574 mac_mount_destroy(mp); 575 #endif 576 if (mp->mnt_opt != NULL) 577 vfs_freeopts(mp->mnt_opt); 578 crfree(mp->mnt_cred); 579 uma_zfree(mount_zone, mp); 580 } 581 582 static int 583 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 584 { 585 struct vfsoptlist *optlist; 586 struct vfsopt *opt, *noro_opt; 587 char *fstype, *fspath, *errmsg; 588 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 589 int has_rw, has_noro; 590 591 errmsg = NULL; 592 errmsg_len = 0; 593 errmsg_pos = -1; 594 has_rw = 0; 595 has_noro = 0; 596 597 error = vfs_buildopts(fsoptions, &optlist); 598 if (error) 599 return (error); 600 601 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 602 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 603 604 /* 605 * We need these two options before the others, 606 * and they are mandatory for any filesystem. 607 * Ensure they are NUL terminated as well. 608 */ 609 fstypelen = 0; 610 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 611 if (error || fstype[fstypelen - 1] != '\0') { 612 error = EINVAL; 613 if (errmsg != NULL) 614 strncpy(errmsg, "Invalid fstype", errmsg_len); 615 goto bail; 616 } 617 fspathlen = 0; 618 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 619 if (error || fspath[fspathlen - 1] != '\0') { 620 error = EINVAL; 621 if (errmsg != NULL) 622 strncpy(errmsg, "Invalid fspath", errmsg_len); 623 goto bail; 624 } 625 626 /* 627 * We need to see if we have the "update" option 628 * before we call vfs_domount(), since vfs_domount() has special 629 * logic based on MNT_UPDATE. This is very important 630 * when we want to update the root filesystem. 631 */ 632 TAILQ_FOREACH(opt, optlist, link) { 633 if (strcmp(opt->name, "update") == 0) 634 fsflags |= MNT_UPDATE; 635 else if (strcmp(opt->name, "async") == 0) 636 fsflags |= MNT_ASYNC; 637 else if (strcmp(opt->name, "force") == 0) 638 fsflags |= MNT_FORCE; 639 else if (strcmp(opt->name, "multilabel") == 0) 640 fsflags |= MNT_MULTILABEL; 641 else if (strcmp(opt->name, "noasync") == 0) 642 fsflags &= ~MNT_ASYNC; 643 else if (strcmp(opt->name, "noatime") == 0) 644 fsflags |= MNT_NOATIME; 645 else if (strcmp(opt->name, "atime") == 0) { 646 free(opt->name, M_MOUNT); 647 opt->name = strdup("nonoatime", M_MOUNT); 648 } 649 else if (strcmp(opt->name, "noclusterr") == 0) 650 fsflags |= MNT_NOCLUSTERR; 651 else if (strcmp(opt->name, "clusterr") == 0) { 652 free(opt->name, M_MOUNT); 653 opt->name = strdup("nonoclusterr", M_MOUNT); 654 } 655 else if (strcmp(opt->name, "noclusterw") == 0) 656 fsflags |= MNT_NOCLUSTERW; 657 else if (strcmp(opt->name, "clusterw") == 0) { 658 free(opt->name, M_MOUNT); 659 opt->name = strdup("nonoclusterw", M_MOUNT); 660 } 661 else if (strcmp(opt->name, "noexec") == 0) 662 fsflags |= MNT_NOEXEC; 663 else if (strcmp(opt->name, "exec") == 0) { 664 free(opt->name, M_MOUNT); 665 opt->name = strdup("nonoexec", M_MOUNT); 666 } 667 else if (strcmp(opt->name, "nosuid") == 0) 668 fsflags |= MNT_NOSUID; 669 else if (strcmp(opt->name, "suid") == 0) { 670 free(opt->name, M_MOUNT); 671 opt->name = strdup("nonosuid", M_MOUNT); 672 } 673 else if (strcmp(opt->name, "nosymfollow") == 0) 674 fsflags |= MNT_NOSYMFOLLOW; 675 else if (strcmp(opt->name, "symfollow") == 0) { 676 free(opt->name, M_MOUNT); 677 opt->name = strdup("nonosymfollow", M_MOUNT); 678 } 679 else if (strcmp(opt->name, "noro") == 0) { 680 fsflags &= ~MNT_RDONLY; 681 has_noro = 1; 682 } 683 else if (strcmp(opt->name, "rw") == 0) { 684 fsflags &= ~MNT_RDONLY; 685 has_rw = 1; 686 } 687 else if (strcmp(opt->name, "ro") == 0 || 688 strcmp(opt->name, "rdonly") == 0) 689 fsflags |= MNT_RDONLY; 690 else if (strcmp(opt->name, "snapshot") == 0) 691 fsflags |= MNT_SNAPSHOT; 692 else if (strcmp(opt->name, "suiddir") == 0) 693 fsflags |= MNT_SUIDDIR; 694 else if (strcmp(opt->name, "sync") == 0) 695 fsflags |= MNT_SYNCHRONOUS; 696 else if (strcmp(opt->name, "union") == 0) 697 fsflags |= MNT_UNION; 698 } 699 700 /* 701 * If "rw" was specified as a mount option, and we 702 * are trying to update a mount-point from "ro" to "rw", 703 * we need a mount option "noro", since in vfs_mergeopts(), 704 * "noro" will cancel "ro", but "rw" will not do anything. 705 */ 706 if (has_rw && !has_noro) { 707 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 708 noro_opt->name = strdup("noro", M_MOUNT); 709 noro_opt->value = NULL; 710 noro_opt->len = 0; 711 TAILQ_INSERT_TAIL(optlist, noro_opt, link); 712 } 713 714 /* 715 * Be ultra-paranoid about making sure the type and fspath 716 * variables will fit in our mp buffers, including the 717 * terminating NUL. 718 */ 719 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 720 error = ENAMETOOLONG; 721 goto bail; 722 } 723 724 mtx_lock(&Giant); 725 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 726 mtx_unlock(&Giant); 727 bail: 728 /* copyout the errmsg */ 729 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 730 && errmsg_len > 0 && errmsg != NULL) { 731 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 732 bcopy(errmsg, 733 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 734 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 735 } else { 736 copyout(errmsg, 737 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 738 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 739 } 740 } 741 742 if (error != 0) 743 vfs_freeopts(optlist); 744 return (error); 745 } 746 747 /* 748 * Old mount API. 749 */ 750 #ifndef _SYS_SYSPROTO_H_ 751 struct mount_args { 752 char *type; 753 char *path; 754 int flags; 755 caddr_t data; 756 }; 757 #endif 758 /* ARGSUSED */ 759 int 760 mount(td, uap) 761 struct thread *td; 762 struct mount_args /* { 763 char *type; 764 char *path; 765 int flags; 766 caddr_t data; 767 } */ *uap; 768 { 769 char *fstype; 770 struct vfsconf *vfsp = NULL; 771 struct mntarg *ma = NULL; 772 int error; 773 774 AUDIT_ARG(fflags, uap->flags); 775 776 /* 777 * Filter out MNT_ROOTFS. We do not want clients of mount() in 778 * userspace to set this flag, but we must filter it out if we want 779 * MNT_UPDATE on the root file system to work. 780 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 781 */ 782 uap->flags &= ~MNT_ROOTFS; 783 784 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 785 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 786 if (error) { 787 free(fstype, M_TEMP); 788 return (error); 789 } 790 791 AUDIT_ARG(text, fstype); 792 mtx_lock(&Giant); 793 vfsp = vfs_byname_kld(fstype, td, &error); 794 free(fstype, M_TEMP); 795 if (vfsp == NULL) { 796 mtx_unlock(&Giant); 797 return (ENOENT); 798 } 799 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 800 mtx_unlock(&Giant); 801 return (EOPNOTSUPP); 802 } 803 804 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 805 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 806 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 807 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 808 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 809 810 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 811 mtx_unlock(&Giant); 812 return (error); 813 } 814 815 816 /* 817 * vfs_domount(): actually attempt a filesystem mount. 818 */ 819 static int 820 vfs_domount( 821 struct thread *td, /* Calling thread. */ 822 const char *fstype, /* Filesystem type. */ 823 char *fspath, /* Mount path. */ 824 int fsflags, /* Flags common to all filesystems. */ 825 void *fsdata /* Options local to the filesystem. */ 826 ) 827 { 828 struct vnode *vp; 829 struct mount *mp; 830 struct vfsconf *vfsp; 831 struct export_args export; 832 int error, flag = 0; 833 struct vattr va; 834 struct nameidata nd; 835 836 mtx_assert(&Giant, MA_OWNED); 837 /* 838 * Be ultra-paranoid about making sure the type and fspath 839 * variables will fit in our mp buffers, including the 840 * terminating NUL. 841 */ 842 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 843 return (ENAMETOOLONG); 844 845 if (jailed(td->td_ucred) || usermount == 0) { 846 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 847 return (error); 848 } 849 850 /* 851 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 852 */ 853 if (fsflags & MNT_EXPORTED) { 854 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 855 if (error) 856 return (error); 857 } 858 if (fsflags & MNT_SUIDDIR) { 859 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 860 if (error) 861 return (error); 862 } 863 /* 864 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 865 */ 866 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 867 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 868 fsflags |= MNT_NOSUID | MNT_USER; 869 } 870 871 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 872 vfsp = NULL; 873 if ((fsflags & MNT_UPDATE) == 0) { 874 /* Don't try to load KLDs if we're mounting the root. */ 875 if (fsflags & MNT_ROOTFS) 876 vfsp = vfs_byname(fstype); 877 else 878 vfsp = vfs_byname_kld(fstype, td, &error); 879 if (vfsp == NULL) 880 return (ENODEV); 881 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 882 return (EPERM); 883 } 884 /* 885 * Get vnode to be covered 886 */ 887 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 888 fspath, td); 889 if ((error = namei(&nd)) != 0) 890 return (error); 891 NDFREE(&nd, NDF_ONLY_PNBUF); 892 vp = nd.ni_vp; 893 if (fsflags & MNT_UPDATE) { 894 if ((vp->v_vflag & VV_ROOT) == 0) { 895 vput(vp); 896 return (EINVAL); 897 } 898 mp = vp->v_mount; 899 MNT_ILOCK(mp); 900 flag = mp->mnt_flag; 901 /* 902 * We only allow the filesystem to be reloaded if it 903 * is currently mounted read-only. 904 */ 905 if ((fsflags & MNT_RELOAD) && 906 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 907 MNT_IUNLOCK(mp); 908 vput(vp); 909 return (EOPNOTSUPP); /* Needs translation */ 910 } 911 MNT_IUNLOCK(mp); 912 /* 913 * Only privileged root, or (if MNT_USER is set) the user that 914 * did the original mount is permitted to update it. 915 */ 916 error = vfs_suser(mp, td); 917 if (error) { 918 vput(vp); 919 return (error); 920 } 921 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 922 vput(vp); 923 return (EBUSY); 924 } 925 VI_LOCK(vp); 926 if ((vp->v_iflag & VI_MOUNT) != 0 || 927 vp->v_mountedhere != NULL) { 928 VI_UNLOCK(vp); 929 vfs_unbusy(mp, td); 930 vput(vp); 931 return (EBUSY); 932 } 933 vp->v_iflag |= VI_MOUNT; 934 VI_UNLOCK(vp); 935 MNT_ILOCK(mp); 936 mp->mnt_flag |= fsflags & 937 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 938 MNT_IUNLOCK(mp); 939 VOP_UNLOCK(vp, 0, td); 940 mp->mnt_optnew = fsdata; 941 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 942 } else { 943 /* 944 * If the user is not root, ensure that they own the directory 945 * onto which we are attempting to mount. 946 */ 947 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 948 if (error) { 949 vput(vp); 950 return (error); 951 } 952 if (va.va_uid != td->td_ucred->cr_uid) { 953 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 954 0); 955 if (error) { 956 vput(vp); 957 return (error); 958 } 959 } 960 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 961 if (error != 0) { 962 vput(vp); 963 return (error); 964 } 965 if (vp->v_type != VDIR) { 966 vput(vp); 967 return (ENOTDIR); 968 } 969 VI_LOCK(vp); 970 if ((vp->v_iflag & VI_MOUNT) != 0 || 971 vp->v_mountedhere != NULL) { 972 VI_UNLOCK(vp); 973 vput(vp); 974 return (EBUSY); 975 } 976 vp->v_iflag |= VI_MOUNT; 977 VI_UNLOCK(vp); 978 979 /* 980 * Allocate and initialize the filesystem. 981 */ 982 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 983 VOP_UNLOCK(vp, 0, td); 984 985 /* XXXMAC: pass to vfs_mount_alloc? */ 986 mp->mnt_optnew = fsdata; 987 } 988 989 /* 990 * Set the mount level flags. 991 */ 992 MNT_ILOCK(mp); 993 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 994 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 995 MNT_RDONLY)); 996 if ((mp->mnt_flag & MNT_ASYNC) == 0) 997 mp->mnt_kern_flag &= ~MNTK_ASYNC; 998 MNT_IUNLOCK(mp); 999 /* 1000 * Mount the filesystem. 1001 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1002 * get. No freeing of cn_pnbuf. 1003 */ 1004 error = VFS_MOUNT(mp, td); 1005 1006 /* 1007 * Process the export option only if we are 1008 * updating mount options. 1009 */ 1010 if (!error && (fsflags & MNT_UPDATE)) { 1011 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1012 sizeof(export)) == 0) 1013 error = vfs_export(mp, &export); 1014 } 1015 1016 if (!error) { 1017 if (mp->mnt_opt != NULL) 1018 vfs_freeopts(mp->mnt_opt); 1019 mp->mnt_opt = mp->mnt_optnew; 1020 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 1021 } 1022 /* 1023 * Prevent external consumers of mount options from reading 1024 * mnt_optnew. 1025 */ 1026 mp->mnt_optnew = NULL; 1027 if (mp->mnt_flag & MNT_UPDATE) { 1028 MNT_ILOCK(mp); 1029 if (error) 1030 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1031 (flag & ~MNT_QUOTA); 1032 else 1033 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1034 MNT_FORCE | MNT_SNAPSHOT); 1035 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1036 mp->mnt_kern_flag |= MNTK_ASYNC; 1037 else 1038 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1039 MNT_IUNLOCK(mp); 1040 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1041 if (mp->mnt_syncer == NULL) 1042 error = vfs_allocate_syncvnode(mp); 1043 } else { 1044 if (mp->mnt_syncer != NULL) 1045 vrele(mp->mnt_syncer); 1046 mp->mnt_syncer = NULL; 1047 } 1048 vfs_unbusy(mp, td); 1049 VI_LOCK(vp); 1050 vp->v_iflag &= ~VI_MOUNT; 1051 VI_UNLOCK(vp); 1052 vrele(vp); 1053 return (error); 1054 } 1055 MNT_ILOCK(mp); 1056 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1057 mp->mnt_kern_flag |= MNTK_ASYNC; 1058 else 1059 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1060 MNT_IUNLOCK(mp); 1061 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 1062 /* 1063 * Put the new filesystem on the mount list after root. 1064 */ 1065 cache_purge(vp); 1066 if (!error) { 1067 struct vnode *newdp; 1068 1069 VI_LOCK(vp); 1070 vp->v_iflag &= ~VI_MOUNT; 1071 VI_UNLOCK(vp); 1072 vp->v_mountedhere = mp; 1073 mtx_lock(&mountlist_mtx); 1074 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1075 mtx_unlock(&mountlist_mtx); 1076 vfs_event_signal(NULL, VQ_MOUNT, 0); 1077 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 1078 panic("mount: lost mount"); 1079 mountcheckdirs(vp, newdp); 1080 vput(newdp); 1081 VOP_UNLOCK(vp, 0, td); 1082 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1083 error = vfs_allocate_syncvnode(mp); 1084 vfs_unbusy(mp, td); 1085 if (error) 1086 vrele(vp); 1087 } else { 1088 VI_LOCK(vp); 1089 vp->v_iflag &= ~VI_MOUNT; 1090 VI_UNLOCK(vp); 1091 vfs_unbusy(mp, td); 1092 vfs_mount_destroy(mp); 1093 vput(vp); 1094 } 1095 return (error); 1096 } 1097 1098 /* 1099 * Unmount a filesystem. 1100 * 1101 * Note: unmount takes a path to the vnode mounted on as argument, not 1102 * special file (as before). 1103 */ 1104 #ifndef _SYS_SYSPROTO_H_ 1105 struct unmount_args { 1106 char *path; 1107 int flags; 1108 }; 1109 #endif 1110 /* ARGSUSED */ 1111 int 1112 unmount(td, uap) 1113 struct thread *td; 1114 register struct unmount_args /* { 1115 char *path; 1116 int flags; 1117 } */ *uap; 1118 { 1119 struct mount *mp; 1120 char *pathbuf; 1121 int error, id0, id1; 1122 1123 if (jailed(td->td_ucred) || usermount == 0) { 1124 error = priv_check(td, PRIV_VFS_UNMOUNT); 1125 if (error) 1126 return (error); 1127 } 1128 1129 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1130 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1131 if (error) { 1132 free(pathbuf, M_TEMP); 1133 return (error); 1134 } 1135 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1); 1136 mtx_lock(&Giant); 1137 if (uap->flags & MNT_BYFSID) { 1138 /* Decode the filesystem ID. */ 1139 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1140 mtx_unlock(&Giant); 1141 free(pathbuf, M_TEMP); 1142 return (EINVAL); 1143 } 1144 1145 mtx_lock(&mountlist_mtx); 1146 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1147 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1148 mp->mnt_stat.f_fsid.val[1] == id1) 1149 break; 1150 } 1151 mtx_unlock(&mountlist_mtx); 1152 } else { 1153 mtx_lock(&mountlist_mtx); 1154 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1155 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1156 break; 1157 } 1158 mtx_unlock(&mountlist_mtx); 1159 } 1160 free(pathbuf, M_TEMP); 1161 if (mp == NULL) { 1162 /* 1163 * Previously we returned ENOENT for a nonexistent path and 1164 * EINVAL for a non-mountpoint. We cannot tell these apart 1165 * now, so in the !MNT_BYFSID case return the more likely 1166 * EINVAL for compatibility. 1167 */ 1168 mtx_unlock(&Giant); 1169 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1170 } 1171 1172 /* 1173 * Don't allow unmounting the root filesystem. 1174 */ 1175 if (mp->mnt_flag & MNT_ROOTFS) { 1176 mtx_unlock(&Giant); 1177 return (EINVAL); 1178 } 1179 error = dounmount(mp, uap->flags, td); 1180 mtx_unlock(&Giant); 1181 return (error); 1182 } 1183 1184 /* 1185 * Do the actual filesystem unmount. 1186 */ 1187 int 1188 dounmount(mp, flags, td) 1189 struct mount *mp; 1190 int flags; 1191 struct thread *td; 1192 { 1193 struct vnode *coveredvp, *fsrootvp; 1194 int error; 1195 int async_flag; 1196 int mnt_gen_r; 1197 1198 mtx_assert(&Giant, MA_OWNED); 1199 1200 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1201 mnt_gen_r = mp->mnt_gen; 1202 VI_LOCK(coveredvp); 1203 vholdl(coveredvp); 1204 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY, td); 1205 vdrop(coveredvp); 1206 /* 1207 * Check for mp being unmounted while waiting for the 1208 * covered vnode lock. 1209 */ 1210 if (coveredvp->v_mountedhere != mp || 1211 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1212 VOP_UNLOCK(coveredvp, 0, td); 1213 return (EBUSY); 1214 } 1215 } 1216 /* 1217 * Only privileged root, or (if MNT_USER is set) the user that did the 1218 * original mount is permitted to unmount this filesystem. 1219 */ 1220 error = vfs_suser(mp, td); 1221 if (error) { 1222 if (coveredvp) 1223 VOP_UNLOCK(coveredvp, 0, td); 1224 return (error); 1225 } 1226 1227 MNT_ILOCK(mp); 1228 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1229 MNT_IUNLOCK(mp); 1230 if (coveredvp) 1231 VOP_UNLOCK(coveredvp, 0, td); 1232 return (EBUSY); 1233 } 1234 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1235 /* Allow filesystems to detect that a forced unmount is in progress. */ 1236 if (flags & MNT_FORCE) 1237 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1238 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1239 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1240 if (error) { 1241 MNT_ILOCK(mp); 1242 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ | 1243 MNTK_UNMOUNTF); 1244 if (mp->mnt_kern_flag & MNTK_MWAIT) 1245 wakeup(mp); 1246 MNT_IUNLOCK(mp); 1247 if (coveredvp) 1248 VOP_UNLOCK(coveredvp, 0, td); 1249 return (error); 1250 } 1251 vn_start_write(NULL, &mp, V_WAIT); 1252 1253 if (mp->mnt_flag & MNT_EXPUBLIC) 1254 vfs_setpublicfs(NULL, NULL, NULL); 1255 1256 vfs_msync(mp, MNT_WAIT); 1257 MNT_ILOCK(mp); 1258 async_flag = mp->mnt_flag & MNT_ASYNC; 1259 mp->mnt_flag &= ~MNT_ASYNC; 1260 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1261 MNT_IUNLOCK(mp); 1262 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1263 if (mp->mnt_syncer != NULL) 1264 vrele(mp->mnt_syncer); 1265 /* 1266 * For forced unmounts, move process cdir/rdir refs on the fs root 1267 * vnode to the covered vnode. For non-forced unmounts we want 1268 * such references to cause an EBUSY error. 1269 */ 1270 if ((flags & MNT_FORCE) && 1271 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1272 if (mp->mnt_vnodecovered != NULL) 1273 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1274 if (fsrootvp == rootvnode) { 1275 vrele(rootvnode); 1276 rootvnode = NULL; 1277 } 1278 vput(fsrootvp); 1279 } 1280 if (((mp->mnt_flag & MNT_RDONLY) || 1281 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1282 (flags & MNT_FORCE)) { 1283 error = VFS_UNMOUNT(mp, flags, td); 1284 } 1285 vn_finished_write(mp); 1286 if (error) { 1287 /* Undo cdir/rdir and rootvnode changes made above. */ 1288 if ((flags & MNT_FORCE) && 1289 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1290 if (mp->mnt_vnodecovered != NULL) 1291 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1292 if (rootvnode == NULL) { 1293 rootvnode = fsrootvp; 1294 vref(rootvnode); 1295 } 1296 vput(fsrootvp); 1297 } 1298 MNT_ILOCK(mp); 1299 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1300 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1301 MNT_IUNLOCK(mp); 1302 (void) vfs_allocate_syncvnode(mp); 1303 MNT_ILOCK(mp); 1304 } 1305 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1306 mp->mnt_flag |= async_flag; 1307 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1308 mp->mnt_kern_flag |= MNTK_ASYNC; 1309 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1310 if (mp->mnt_kern_flag & MNTK_MWAIT) 1311 wakeup(mp); 1312 MNT_IUNLOCK(mp); 1313 if (coveredvp) 1314 VOP_UNLOCK(coveredvp, 0, td); 1315 return (error); 1316 } 1317 mtx_lock(&mountlist_mtx); 1318 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1319 mtx_unlock(&mountlist_mtx); 1320 if (coveredvp != NULL) { 1321 coveredvp->v_mountedhere = NULL; 1322 vput(coveredvp); 1323 } 1324 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1325 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1326 vfs_mount_destroy(mp); 1327 return (0); 1328 } 1329 1330 /* 1331 * --------------------------------------------------------------------- 1332 * Mounting of root filesystem 1333 * 1334 */ 1335 1336 struct root_hold_token { 1337 const char *who; 1338 LIST_ENTRY(root_hold_token) list; 1339 }; 1340 1341 static LIST_HEAD(, root_hold_token) root_holds = 1342 LIST_HEAD_INITIALIZER(&root_holds); 1343 1344 static int root_mount_complete; 1345 1346 /* 1347 * Hold root mount. 1348 */ 1349 struct root_hold_token * 1350 root_mount_hold(const char *identifier) 1351 { 1352 struct root_hold_token *h; 1353 1354 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1355 h->who = identifier; 1356 mtx_lock(&mountlist_mtx); 1357 LIST_INSERT_HEAD(&root_holds, h, list); 1358 mtx_unlock(&mountlist_mtx); 1359 return (h); 1360 } 1361 1362 /* 1363 * Release root mount. 1364 */ 1365 void 1366 root_mount_rel(struct root_hold_token *h) 1367 { 1368 1369 mtx_lock(&mountlist_mtx); 1370 LIST_REMOVE(h, list); 1371 wakeup(&root_holds); 1372 mtx_unlock(&mountlist_mtx); 1373 free(h, M_DEVBUF); 1374 } 1375 1376 /* 1377 * Wait for all subsystems to release root mount. 1378 */ 1379 static void 1380 root_mount_prepare(void) 1381 { 1382 struct root_hold_token *h; 1383 1384 for (;;) { 1385 DROP_GIANT(); 1386 g_waitidle(); 1387 PICKUP_GIANT(); 1388 mtx_lock(&mountlist_mtx); 1389 if (LIST_EMPTY(&root_holds)) { 1390 mtx_unlock(&mountlist_mtx); 1391 break; 1392 } 1393 printf("Root mount waiting for:"); 1394 LIST_FOREACH(h, &root_holds, list) 1395 printf(" %s", h->who); 1396 printf("\n"); 1397 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1398 hz); 1399 } 1400 } 1401 1402 /* 1403 * Root was mounted, share the good news. 1404 */ 1405 static void 1406 root_mount_done(void) 1407 { 1408 1409 /* 1410 * Use a mutex to prevent the wakeup being missed and waiting for 1411 * an extra 1 second sleep. 1412 */ 1413 mtx_lock(&mountlist_mtx); 1414 root_mount_complete = 1; 1415 wakeup(&root_mount_complete); 1416 mtx_unlock(&mountlist_mtx); 1417 } 1418 1419 /* 1420 * Return true if root is already mounted. 1421 */ 1422 int 1423 root_mounted(void) 1424 { 1425 1426 /* No mutex is acquired here because int stores are atomic. */ 1427 return (root_mount_complete); 1428 } 1429 1430 /* 1431 * Wait until root is mounted. 1432 */ 1433 void 1434 root_mount_wait(void) 1435 { 1436 1437 /* 1438 * Panic on an obvious deadlock - the function can't be called from 1439 * a thread which is doing the whole SYSINIT stuff. 1440 */ 1441 KASSERT(curthread->td_proc->p_pid != 0, 1442 ("root_mount_wait: cannot be called from the swapper thread")); 1443 mtx_lock(&mountlist_mtx); 1444 while (!root_mount_complete) { 1445 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1446 hz); 1447 } 1448 mtx_unlock(&mountlist_mtx); 1449 } 1450 1451 static void 1452 set_rootvnode(struct thread *td) 1453 { 1454 struct proc *p; 1455 1456 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1457 panic("Cannot find root vnode"); 1458 1459 p = td->td_proc; 1460 FILEDESC_SLOCK(p->p_fd); 1461 1462 if (p->p_fd->fd_cdir != NULL) 1463 vrele(p->p_fd->fd_cdir); 1464 p->p_fd->fd_cdir = rootvnode; 1465 VREF(rootvnode); 1466 1467 if (p->p_fd->fd_rdir != NULL) 1468 vrele(p->p_fd->fd_rdir); 1469 p->p_fd->fd_rdir = rootvnode; 1470 VREF(rootvnode); 1471 1472 FILEDESC_SUNLOCK(p->p_fd); 1473 1474 VOP_UNLOCK(rootvnode, 0, td); 1475 } 1476 1477 /* 1478 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1479 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1480 */ 1481 1482 static void 1483 devfs_first(void) 1484 { 1485 struct thread *td = curthread; 1486 struct vfsoptlist *opts; 1487 struct vfsconf *vfsp; 1488 struct mount *mp = NULL; 1489 int error; 1490 1491 vfsp = vfs_byname("devfs"); 1492 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1493 if (vfsp == NULL) 1494 return; 1495 1496 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1497 1498 error = VFS_MOUNT(mp, td); 1499 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1500 if (error) 1501 return; 1502 1503 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1504 TAILQ_INIT(opts); 1505 mp->mnt_opt = opts; 1506 1507 mtx_lock(&mountlist_mtx); 1508 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1509 mtx_unlock(&mountlist_mtx); 1510 1511 set_rootvnode(td); 1512 1513 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1514 if (error) 1515 printf("kern_symlink /dev -> / returns %d\n", error); 1516 } 1517 1518 /* 1519 * Surgically move our devfs to be mounted on /dev. 1520 */ 1521 1522 static void 1523 devfs_fixup(struct thread *td) 1524 { 1525 struct nameidata nd; 1526 int error; 1527 struct vnode *vp, *dvp; 1528 struct mount *mp; 1529 1530 /* Remove our devfs mount from the mountlist and purge the cache */ 1531 mtx_lock(&mountlist_mtx); 1532 mp = TAILQ_FIRST(&mountlist); 1533 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1534 mtx_unlock(&mountlist_mtx); 1535 cache_purgevfs(mp); 1536 1537 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1538 VI_LOCK(dvp); 1539 dvp->v_iflag &= ~VI_MOUNT; 1540 VI_UNLOCK(dvp); 1541 dvp->v_mountedhere = NULL; 1542 1543 /* Set up the real rootvnode, and purge the cache */ 1544 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1545 set_rootvnode(td); 1546 cache_purgevfs(rootvnode->v_mount); 1547 1548 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1549 error = namei(&nd); 1550 if (error) { 1551 printf("Lookup of /dev for devfs, error: %d\n", error); 1552 return; 1553 } 1554 NDFREE(&nd, NDF_ONLY_PNBUF); 1555 vp = nd.ni_vp; 1556 if (vp->v_type != VDIR) { 1557 vput(vp); 1558 } 1559 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1560 if (error) { 1561 vput(vp); 1562 } 1563 cache_purge(vp); 1564 mp->mnt_vnodecovered = vp; 1565 vp->v_mountedhere = mp; 1566 mtx_lock(&mountlist_mtx); 1567 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1568 mtx_unlock(&mountlist_mtx); 1569 VOP_UNLOCK(vp, 0, td); 1570 vput(dvp); 1571 vfs_unbusy(mp, td); 1572 1573 /* Unlink the no longer needed /dev/dev -> / symlink */ 1574 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1575 } 1576 1577 /* 1578 * Report errors during filesystem mounting. 1579 */ 1580 void 1581 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1582 { 1583 struct vfsoptlist *moptlist = mp->mnt_optnew; 1584 va_list ap; 1585 int error, len; 1586 char *errmsg; 1587 1588 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1589 if (error || errmsg == NULL || len <= 0) 1590 return; 1591 1592 va_start(ap, fmt); 1593 vsnprintf(errmsg, (size_t)len, fmt, ap); 1594 va_end(ap); 1595 } 1596 1597 /* 1598 * Find and mount the root filesystem 1599 */ 1600 void 1601 vfs_mountroot(void) 1602 { 1603 char *cp; 1604 int error, i, asked = 0; 1605 1606 root_mount_prepare(); 1607 1608 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1609 NULL, NULL, mount_init, mount_fini, 1610 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1611 devfs_first(); 1612 1613 /* 1614 * We are booted with instructions to prompt for the root filesystem. 1615 */ 1616 if (boothowto & RB_ASKNAME) { 1617 if (!vfs_mountroot_ask()) 1618 goto mounted; 1619 asked = 1; 1620 } 1621 1622 /* 1623 * The root filesystem information is compiled in, and we are 1624 * booted with instructions to use it. 1625 */ 1626 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1627 if (!vfs_mountroot_try(ctrootdevname)) 1628 goto mounted; 1629 ctrootdevname = NULL; 1630 } 1631 1632 /* 1633 * We've been given the generic "use CDROM as root" flag. This is 1634 * necessary because one media may be used in many different 1635 * devices, so we need to search for them. 1636 */ 1637 if (boothowto & RB_CDROM) { 1638 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1639 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1640 goto mounted; 1641 } 1642 } 1643 1644 /* 1645 * Try to use the value read by the loader from /etc/fstab, or 1646 * supplied via some other means. This is the preferred 1647 * mechanism. 1648 */ 1649 cp = getenv("vfs.root.mountfrom"); 1650 if (cp != NULL) { 1651 error = vfs_mountroot_try(cp); 1652 freeenv(cp); 1653 if (!error) 1654 goto mounted; 1655 } 1656 1657 /* 1658 * Try values that may have been computed by code during boot 1659 */ 1660 if (!vfs_mountroot_try(rootdevnames[0])) 1661 goto mounted; 1662 if (!vfs_mountroot_try(rootdevnames[1])) 1663 goto mounted; 1664 1665 /* 1666 * If we (still) have a compiled-in default, try it. 1667 */ 1668 if (ctrootdevname != NULL) 1669 if (!vfs_mountroot_try(ctrootdevname)) 1670 goto mounted; 1671 /* 1672 * Everything so far has failed, prompt on the console if we haven't 1673 * already tried that. 1674 */ 1675 if (!asked) 1676 if (!vfs_mountroot_ask()) 1677 goto mounted; 1678 1679 panic("Root mount failed, startup aborted."); 1680 1681 mounted: 1682 root_mount_done(); 1683 } 1684 1685 /* 1686 * Mount (mountfrom) as the root filesystem. 1687 */ 1688 static int 1689 vfs_mountroot_try(const char *mountfrom) 1690 { 1691 struct mount *mp; 1692 char *vfsname, *path; 1693 time_t timebase; 1694 int error; 1695 char patt[32]; 1696 1697 vfsname = NULL; 1698 path = NULL; 1699 mp = NULL; 1700 error = EINVAL; 1701 1702 if (mountfrom == NULL) 1703 return (error); /* don't complain */ 1704 printf("Trying to mount root from %s\n", mountfrom); 1705 1706 /* parse vfs name and path */ 1707 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1708 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1709 vfsname[0] = path[0] = 0; 1710 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1711 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1712 goto out; 1713 1714 if (path[0] == '\0') 1715 strcpy(path, ROOTNAME); 1716 1717 error = kernel_vmount( 1718 MNT_RDONLY | MNT_ROOTFS, 1719 "fstype", vfsname, 1720 "fspath", "/", 1721 "from", path, 1722 NULL); 1723 if (error == 0) { 1724 /* 1725 * We mount devfs prior to mounting the / FS, so the first 1726 * entry will typically be devfs. 1727 */ 1728 mp = TAILQ_FIRST(&mountlist); 1729 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1730 1731 /* 1732 * Iterate over all currently mounted file systems and use 1733 * the time stamp found to check and/or initialize the RTC. 1734 * Typically devfs has no time stamp and the only other FS 1735 * is the actual / FS. 1736 * Call inittodr() only once and pass it the largest of the 1737 * timestamps we encounter. 1738 */ 1739 timebase = 0; 1740 do { 1741 if (mp->mnt_time > timebase) 1742 timebase = mp->mnt_time; 1743 mp = TAILQ_NEXT(mp, mnt_list); 1744 } while (mp != NULL); 1745 inittodr(timebase); 1746 1747 devfs_fixup(curthread); 1748 } 1749 out: 1750 free(path, M_MOUNT); 1751 free(vfsname, M_MOUNT); 1752 return (error); 1753 } 1754 1755 /* 1756 * --------------------------------------------------------------------- 1757 * Interactive root filesystem selection code. 1758 */ 1759 1760 static int 1761 vfs_mountroot_ask(void) 1762 { 1763 char name[128]; 1764 1765 for(;;) { 1766 printf("\nManual root filesystem specification:\n"); 1767 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1768 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1769 printf(" eg. ufs:da0s1a\n"); 1770 #else 1771 printf(" eg. ufs:/dev/da0a\n"); 1772 #endif 1773 printf(" ? List valid disk boot devices\n"); 1774 printf(" <empty line> Abort manual input\n"); 1775 printf("\nmountroot> "); 1776 gets(name, sizeof(name), 1); 1777 if (name[0] == '\0') 1778 return (1); 1779 if (name[0] == '?') { 1780 printf("\nList of GEOM managed disk devices:\n "); 1781 g_dev_print(); 1782 continue; 1783 } 1784 if (!vfs_mountroot_try(name)) 1785 return (0); 1786 } 1787 } 1788 1789 /* 1790 * --------------------------------------------------------------------- 1791 * Functions for querying mount options/arguments from filesystems. 1792 */ 1793 1794 /* 1795 * Check that no unknown options are given 1796 */ 1797 int 1798 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1799 { 1800 struct vfsopt *opt; 1801 char errmsg[255]; 1802 const char **t, *p, *q; 1803 int ret = 0; 1804 1805 TAILQ_FOREACH(opt, opts, link) { 1806 p = opt->name; 1807 q = NULL; 1808 if (p[0] == 'n' && p[1] == 'o') 1809 q = p + 2; 1810 for(t = global_opts; *t != NULL; t++) { 1811 if (strcmp(*t, p) == 0) 1812 break; 1813 if (q != NULL) { 1814 if (strcmp(*t, q) == 0) 1815 break; 1816 } 1817 } 1818 if (*t != NULL) 1819 continue; 1820 for(t = legal; *t != NULL; t++) { 1821 if (strcmp(*t, p) == 0) 1822 break; 1823 if (q != NULL) { 1824 if (strcmp(*t, q) == 0) 1825 break; 1826 } 1827 } 1828 if (*t != NULL) 1829 continue; 1830 sprintf(errmsg, "mount option <%s> is unknown", p); 1831 printf("%s\n", errmsg); 1832 ret = EINVAL; 1833 } 1834 if (ret != 0) { 1835 TAILQ_FOREACH(opt, opts, link) { 1836 if (strcmp(opt->name, "errmsg") == 0) { 1837 strncpy((char *)opt->value, errmsg, opt->len); 1838 } 1839 } 1840 } 1841 return (ret); 1842 } 1843 1844 /* 1845 * Get a mount option by its name. 1846 * 1847 * Return 0 if the option was found, ENOENT otherwise. 1848 * If len is non-NULL it will be filled with the length 1849 * of the option. If buf is non-NULL, it will be filled 1850 * with the address of the option. 1851 */ 1852 int 1853 vfs_getopt(opts, name, buf, len) 1854 struct vfsoptlist *opts; 1855 const char *name; 1856 void **buf; 1857 int *len; 1858 { 1859 struct vfsopt *opt; 1860 1861 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1862 1863 TAILQ_FOREACH(opt, opts, link) { 1864 if (strcmp(name, opt->name) == 0) { 1865 if (len != NULL) 1866 *len = opt->len; 1867 if (buf != NULL) 1868 *buf = opt->value; 1869 return (0); 1870 } 1871 } 1872 return (ENOENT); 1873 } 1874 1875 static int 1876 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1877 { 1878 struct vfsopt *opt; 1879 int i; 1880 1881 if (opts == NULL) 1882 return (-1); 1883 1884 i = 0; 1885 TAILQ_FOREACH(opt, opts, link) { 1886 if (strcmp(name, opt->name) == 0) 1887 return (i); 1888 ++i; 1889 } 1890 return (-1); 1891 } 1892 1893 char * 1894 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1895 { 1896 struct vfsopt *opt; 1897 1898 *error = 0; 1899 TAILQ_FOREACH(opt, opts, link) { 1900 if (strcmp(name, opt->name) != 0) 1901 continue; 1902 if (((char *)opt->value)[opt->len - 1] != '\0') { 1903 *error = EINVAL; 1904 return (NULL); 1905 } 1906 return (opt->value); 1907 } 1908 *error = ENOENT; 1909 return (NULL); 1910 } 1911 1912 int 1913 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1914 { 1915 struct vfsopt *opt; 1916 1917 TAILQ_FOREACH(opt, opts, link) { 1918 if (strcmp(name, opt->name) == 0) { 1919 if (w != NULL) 1920 *w |= val; 1921 return (1); 1922 } 1923 } 1924 if (w != NULL) 1925 *w &= ~val; 1926 return (0); 1927 } 1928 1929 int 1930 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1931 { 1932 va_list ap; 1933 struct vfsopt *opt; 1934 int ret; 1935 1936 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1937 1938 TAILQ_FOREACH(opt, opts, link) { 1939 if (strcmp(name, opt->name) != 0) 1940 continue; 1941 if (((char *)opt->value)[opt->len - 1] != '\0') 1942 return (0); 1943 va_start(ap, fmt); 1944 ret = vsscanf(opt->value, fmt, ap); 1945 va_end(ap); 1946 return (ret); 1947 } 1948 return (0); 1949 } 1950 1951 /* 1952 * Find and copy a mount option. 1953 * 1954 * The size of the buffer has to be specified 1955 * in len, if it is not the same length as the 1956 * mount option, EINVAL is returned. 1957 * Returns ENOENT if the option is not found. 1958 */ 1959 int 1960 vfs_copyopt(opts, name, dest, len) 1961 struct vfsoptlist *opts; 1962 const char *name; 1963 void *dest; 1964 int len; 1965 { 1966 struct vfsopt *opt; 1967 1968 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1969 1970 TAILQ_FOREACH(opt, opts, link) { 1971 if (strcmp(name, opt->name) == 0) { 1972 if (len != opt->len) 1973 return (EINVAL); 1974 bcopy(opt->value, dest, opt->len); 1975 return (0); 1976 } 1977 } 1978 return (ENOENT); 1979 } 1980 1981 /* 1982 * This is a helper function for filesystems to traverse their 1983 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1984 */ 1985 1986 struct vnode * 1987 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 1988 { 1989 struct vnode *vp; 1990 1991 mtx_assert(MNT_MTX(mp), MA_OWNED); 1992 1993 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 1994 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 1995 while (vp != NULL && vp->v_type == VMARKER) 1996 vp = TAILQ_NEXT(vp, v_nmntvnodes); 1997 1998 /* Check if we are done */ 1999 if (vp == NULL) { 2000 __mnt_vnode_markerfree(mvp, mp); 2001 return (NULL); 2002 } 2003 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2004 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2005 return (vp); 2006 } 2007 2008 struct vnode * 2009 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2010 { 2011 struct vnode *vp; 2012 2013 mtx_assert(MNT_MTX(mp), MA_OWNED); 2014 2015 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2016 while (vp != NULL && vp->v_type == VMARKER) 2017 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2018 2019 /* Check if we are done */ 2020 if (vp == NULL) { 2021 *mvp = NULL; 2022 return (NULL); 2023 } 2024 mp->mnt_holdcnt++; 2025 MNT_IUNLOCK(mp); 2026 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2027 M_VNODE_MARKER, 2028 M_WAITOK | M_ZERO); 2029 MNT_ILOCK(mp); 2030 (*mvp)->v_type = VMARKER; 2031 2032 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2033 while (vp != NULL && vp->v_type == VMARKER) 2034 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2035 2036 /* Check if we are done */ 2037 if (vp == NULL) { 2038 MNT_IUNLOCK(mp); 2039 free(*mvp, M_VNODE_MARKER); 2040 MNT_ILOCK(mp); 2041 *mvp = NULL; 2042 mp->mnt_holdcnt--; 2043 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2044 wakeup(&mp->mnt_holdcnt); 2045 return (NULL); 2046 } 2047 mp->mnt_markercnt++; 2048 (*mvp)->v_mount = mp; 2049 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2050 return (vp); 2051 } 2052 2053 2054 void 2055 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2056 { 2057 2058 if (*mvp == NULL) 2059 return; 2060 2061 mtx_assert(MNT_MTX(mp), MA_OWNED); 2062 2063 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2064 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2065 MNT_IUNLOCK(mp); 2066 free(*mvp, M_VNODE_MARKER); 2067 MNT_ILOCK(mp); 2068 *mvp = NULL; 2069 2070 mp->mnt_markercnt--; 2071 mp->mnt_holdcnt--; 2072 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2073 wakeup(&mp->mnt_holdcnt); 2074 } 2075 2076 2077 int 2078 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 2079 { 2080 int error; 2081 2082 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 2083 if (sbp != &mp->mnt_stat) 2084 *sbp = mp->mnt_stat; 2085 return (error); 2086 } 2087 2088 void 2089 vfs_mountedfrom(struct mount *mp, const char *from) 2090 { 2091 2092 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2093 strlcpy(mp->mnt_stat.f_mntfromname, from, 2094 sizeof mp->mnt_stat.f_mntfromname); 2095 } 2096 2097 /* 2098 * --------------------------------------------------------------------- 2099 * This is the api for building mount args and mounting filesystems from 2100 * inside the kernel. 2101 * 2102 * The API works by accumulation of individual args. First error is 2103 * latched. 2104 * 2105 * XXX: should be documented in new manpage kernel_mount(9) 2106 */ 2107 2108 /* A memory allocation which must be freed when we are done */ 2109 struct mntaarg { 2110 SLIST_ENTRY(mntaarg) next; 2111 }; 2112 2113 /* The header for the mount arguments */ 2114 struct mntarg { 2115 struct iovec *v; 2116 int len; 2117 int error; 2118 SLIST_HEAD(, mntaarg) list; 2119 }; 2120 2121 /* 2122 * Add a boolean argument. 2123 * 2124 * flag is the boolean value. 2125 * name must start with "no". 2126 */ 2127 struct mntarg * 2128 mount_argb(struct mntarg *ma, int flag, const char *name) 2129 { 2130 2131 KASSERT(name[0] == 'n' && name[1] == 'o', 2132 ("mount_argb(...,%s): name must start with 'no'", name)); 2133 2134 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2135 } 2136 2137 /* 2138 * Add an argument printf style 2139 */ 2140 struct mntarg * 2141 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2142 { 2143 va_list ap; 2144 struct mntaarg *maa; 2145 struct sbuf *sb; 2146 int len; 2147 2148 if (ma == NULL) { 2149 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2150 SLIST_INIT(&ma->list); 2151 } 2152 if (ma->error) 2153 return (ma); 2154 2155 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2156 M_MOUNT, M_WAITOK); 2157 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2158 ma->v[ma->len].iov_len = strlen(name) + 1; 2159 ma->len++; 2160 2161 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 2162 va_start(ap, fmt); 2163 sbuf_vprintf(sb, fmt, ap); 2164 va_end(ap); 2165 sbuf_finish(sb); 2166 len = sbuf_len(sb) + 1; 2167 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2168 SLIST_INSERT_HEAD(&ma->list, maa, next); 2169 bcopy(sbuf_data(sb), maa + 1, len); 2170 sbuf_delete(sb); 2171 2172 ma->v[ma->len].iov_base = maa + 1; 2173 ma->v[ma->len].iov_len = len; 2174 ma->len++; 2175 2176 return (ma); 2177 } 2178 2179 /* 2180 * Add an argument which is a userland string. 2181 */ 2182 struct mntarg * 2183 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2184 { 2185 struct mntaarg *maa; 2186 char *tbuf; 2187 2188 if (val == NULL) 2189 return (ma); 2190 if (ma == NULL) { 2191 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2192 SLIST_INIT(&ma->list); 2193 } 2194 if (ma->error) 2195 return (ma); 2196 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2197 SLIST_INSERT_HEAD(&ma->list, maa, next); 2198 tbuf = (void *)(maa + 1); 2199 ma->error = copyinstr(val, tbuf, len, NULL); 2200 return (mount_arg(ma, name, tbuf, -1)); 2201 } 2202 2203 /* 2204 * Plain argument. 2205 * 2206 * If length is -1, use printf. 2207 */ 2208 struct mntarg * 2209 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2210 { 2211 2212 if (ma == NULL) { 2213 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2214 SLIST_INIT(&ma->list); 2215 } 2216 if (ma->error) 2217 return (ma); 2218 2219 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2220 M_MOUNT, M_WAITOK); 2221 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2222 ma->v[ma->len].iov_len = strlen(name) + 1; 2223 ma->len++; 2224 2225 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2226 if (len < 0) 2227 ma->v[ma->len].iov_len = strlen(val) + 1; 2228 else 2229 ma->v[ma->len].iov_len = len; 2230 ma->len++; 2231 return (ma); 2232 } 2233 2234 /* 2235 * Free a mntarg structure 2236 */ 2237 static void 2238 free_mntarg(struct mntarg *ma) 2239 { 2240 struct mntaarg *maa; 2241 2242 while (!SLIST_EMPTY(&ma->list)) { 2243 maa = SLIST_FIRST(&ma->list); 2244 SLIST_REMOVE_HEAD(&ma->list, next); 2245 free(maa, M_MOUNT); 2246 } 2247 free(ma->v, M_MOUNT); 2248 free(ma, M_MOUNT); 2249 } 2250 2251 /* 2252 * Mount a filesystem 2253 */ 2254 int 2255 kernel_mount(struct mntarg *ma, int flags) 2256 { 2257 struct uio auio; 2258 int error; 2259 2260 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2261 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2262 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2263 2264 auio.uio_iov = ma->v; 2265 auio.uio_iovcnt = ma->len; 2266 auio.uio_segflg = UIO_SYSSPACE; 2267 2268 error = ma->error; 2269 if (!error) 2270 error = vfs_donmount(curthread, flags, &auio); 2271 free_mntarg(ma); 2272 return (error); 2273 } 2274 2275 /* 2276 * A printflike function to mount a filesystem. 2277 */ 2278 int 2279 kernel_vmount(int flags, ...) 2280 { 2281 struct mntarg *ma = NULL; 2282 va_list ap; 2283 const char *cp; 2284 const void *vp; 2285 int error; 2286 2287 va_start(ap, flags); 2288 for (;;) { 2289 cp = va_arg(ap, const char *); 2290 if (cp == NULL) 2291 break; 2292 vp = va_arg(ap, const void *); 2293 ma = mount_arg(ma, cp, vp, -1); 2294 } 2295 va_end(ap); 2296 2297 error = kernel_mount(ma, flags); 2298 return (error); 2299 } 2300