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/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 #include "opt_mac.h" 72 73 #define ROOTNAME "root_device" 74 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 75 76 static int vfs_domount(struct thread *td, const char *fstype, 77 char *fspath, int fsflags, void *fsdata); 78 static int vfs_mountroot_ask(void); 79 static int vfs_mountroot_try(const char *mountfrom); 80 static int vfs_donmount(struct thread *td, int fsflags, 81 struct uio *fsoptions); 82 static void free_mntarg(struct mntarg *ma); 83 static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 84 85 static int usermount = 0; 86 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 87 "Unprivileged users may mount and unmount file systems"); 88 89 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 90 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 91 static uma_zone_t mount_zone; 92 93 /* List of mounted filesystems. */ 94 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 95 96 /* For any iteration/modification of mountlist */ 97 struct mtx mountlist_mtx; 98 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 99 100 TAILQ_HEAD(vfsoptlist, vfsopt); 101 struct vfsopt { 102 TAILQ_ENTRY(vfsopt) link; 103 char *name; 104 void *value; 105 int len; 106 }; 107 108 /* 109 * The vnode of the system's root (/ in the filesystem, without chroot 110 * active.) 111 */ 112 struct vnode *rootvnode; 113 114 /* 115 * The root filesystem is detailed in the kernel environment variable 116 * vfs.root.mountfrom, which is expected to be in the general format 117 * 118 * <vfsname>:[<path>] 119 * vfsname := the name of a VFS known to the kernel and capable 120 * of being mounted as root 121 * path := disk device name or other data used by the filesystem 122 * to locate its physical store 123 */ 124 125 /* 126 * Global opts, taken by all filesystems 127 */ 128 static const char *global_opts[] = { 129 "errmsg", 130 "fstype", 131 "fspath", 132 "ro", 133 "rw", 134 "nosuid", 135 "noexec", 136 NULL 137 }; 138 139 /* 140 * The root specifiers we will try if RB_CDROM is specified. 141 */ 142 static char *cdrom_rootdevnames[] = { 143 "cd9660:cd0", 144 "cd9660:acd0", 145 NULL 146 }; 147 148 /* legacy find-root code */ 149 char *rootdevnames[2] = {NULL, NULL}; 150 #ifndef ROOTDEVNAME 151 # define ROOTDEVNAME NULL 152 #endif 153 static const char *ctrootdevname = ROOTDEVNAME; 154 155 /* 156 * --------------------------------------------------------------------- 157 * Functions for building and sanitizing the mount options 158 */ 159 160 /* Remove one mount option. */ 161 static void 162 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 163 { 164 165 TAILQ_REMOVE(opts, opt, link); 166 free(opt->name, M_MOUNT); 167 if (opt->value != NULL) 168 free(opt->value, M_MOUNT); 169 #ifdef INVARIANTS 170 else if (opt->len != 0) 171 panic("%s: mount option with NULL value but length != 0", 172 __func__); 173 #endif 174 free(opt, M_MOUNT); 175 } 176 177 /* Release all resources related to the mount options. */ 178 void 179 vfs_freeopts(struct vfsoptlist *opts) 180 { 181 struct vfsopt *opt; 182 183 while (!TAILQ_EMPTY(opts)) { 184 opt = TAILQ_FIRST(opts); 185 vfs_freeopt(opts, opt); 186 } 187 free(opts, M_MOUNT); 188 } 189 190 void 191 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 192 { 193 struct vfsopt *opt, *temp; 194 195 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 196 if (strcmp(opt->name, name) == 0) 197 vfs_freeopt(opts, opt); 198 } 199 } 200 201 /* 202 * Check if options are equal (with or without the "no" prefix). 203 */ 204 static int 205 vfs_equalopts(const char *opt1, const char *opt2) 206 { 207 208 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 209 if (strcmp(opt1, opt2) == 0) 210 return (1); 211 /* "noopt" vs. "opt" */ 212 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 213 return (1); 214 /* "opt" vs. "noopt" */ 215 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 216 return (1); 217 return (0); 218 } 219 220 /* 221 * If a mount option is specified several times, 222 * (with or without the "no" prefix) only keep 223 * the last occurence of it. 224 */ 225 static void 226 vfs_sanitizeopts(struct vfsoptlist *opts) 227 { 228 struct vfsopt *opt, *opt2, *tmp; 229 230 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 231 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 232 while (opt2 != NULL) { 233 if (vfs_equalopts(opt->name, opt2->name)) { 234 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 235 vfs_freeopt(opts, opt2); 236 opt2 = tmp; 237 } else { 238 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 239 } 240 } 241 } 242 } 243 244 /* 245 * Build a linked list of mount options from a struct uio. 246 */ 247 static int 248 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 249 { 250 struct vfsoptlist *opts; 251 struct vfsopt *opt; 252 size_t memused; 253 unsigned int i, iovcnt; 254 int error, namelen, optlen; 255 256 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 257 TAILQ_INIT(opts); 258 memused = 0; 259 iovcnt = auio->uio_iovcnt; 260 for (i = 0; i < iovcnt; i += 2) { 261 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 262 namelen = auio->uio_iov[i].iov_len; 263 optlen = auio->uio_iov[i + 1].iov_len; 264 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 265 opt->value = NULL; 266 opt->len = 0; 267 268 /* 269 * Do this early, so jumps to "bad" will free the current 270 * option. 271 */ 272 TAILQ_INSERT_TAIL(opts, opt, link); 273 memused += sizeof(struct vfsopt) + optlen + namelen; 274 275 /* 276 * Avoid consuming too much memory, and attempts to overflow 277 * memused. 278 */ 279 if (memused > VFS_MOUNTARG_SIZE_MAX || 280 optlen > VFS_MOUNTARG_SIZE_MAX || 281 namelen > VFS_MOUNTARG_SIZE_MAX) { 282 error = EINVAL; 283 goto bad; 284 } 285 286 if (auio->uio_segflg == UIO_SYSSPACE) { 287 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 288 } else { 289 error = copyin(auio->uio_iov[i].iov_base, opt->name, 290 namelen); 291 if (error) 292 goto bad; 293 } 294 /* Ensure names are null-terminated strings. */ 295 if (opt->name[namelen - 1] != '\0') { 296 error = EINVAL; 297 goto bad; 298 } 299 if (optlen != 0) { 300 opt->len = optlen; 301 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 302 if (auio->uio_segflg == UIO_SYSSPACE) { 303 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 304 optlen); 305 } else { 306 error = copyin(auio->uio_iov[i + 1].iov_base, 307 opt->value, optlen); 308 if (error) 309 goto bad; 310 } 311 } 312 } 313 vfs_sanitizeopts(opts); 314 *options = opts; 315 return (0); 316 bad: 317 vfs_freeopts(opts); 318 return (error); 319 } 320 321 /* 322 * Merge the old mount options with the new ones passed 323 * in the MNT_UPDATE case. 324 * 325 * XXX This function will keep a "nofoo" option in the 326 * new options if there is no matching "foo" option 327 * to be cancelled in the old options. This is a bug 328 * if the option's canonical name is "foo". E.g., "noro" 329 * shouldn't end up in the mount point's active options, 330 * but it can. 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 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 455 return (0); 456 } 457 458 static void 459 mount_fini(void *mem, int size) 460 { 461 struct mount *mp; 462 463 mp = (struct mount *)mem; 464 lockdestroy(&mp->mnt_explock); 465 lockdestroy(&mp->mnt_lock); 466 mtx_destroy(&mp->mnt_mtx); 467 } 468 469 /* 470 * Allocate and initialize the mount point struct. 471 */ 472 struct mount * 473 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 474 const char *fspath, struct thread *td) 475 { 476 struct mount *mp; 477 478 mp = uma_zalloc(mount_zone, M_WAITOK); 479 bzero(&mp->mnt_startzero, 480 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 481 TAILQ_INIT(&mp->mnt_nvnodelist); 482 mp->mnt_nvnodelistsize = 0; 483 mp->mnt_ref = 0; 484 (void) vfs_busy(mp, LK_NOWAIT, 0, td); 485 mp->mnt_op = vfsp->vfc_vfsops; 486 mp->mnt_vfc = vfsp; 487 vfsp->vfc_refcount++; /* XXX Unlocked */ 488 mp->mnt_stat.f_type = vfsp->vfc_typenum; 489 mp->mnt_gen++; 490 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 491 mp->mnt_vnodecovered = vp; 492 mp->mnt_cred = crdup(td->td_ucred); 493 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 494 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 495 mp->mnt_iosize_max = DFLTPHYS; 496 #ifdef MAC 497 mac_mount_init(mp); 498 mac_mount_create(td->td_ucred, mp); 499 #endif 500 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 501 return (mp); 502 } 503 504 /* 505 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 506 */ 507 void 508 vfs_mount_destroy(struct mount *mp) 509 { 510 int i; 511 512 MNT_ILOCK(mp); 513 for (i = 0; mp->mnt_ref && i < 3; i++) 514 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 515 /* 516 * This will always cause a 3 second delay in rebooting due to 517 * refs on the root mountpoint that never go away. Most of these 518 * are held by init which never exits. 519 */ 520 if (i == 3 && (!rebooting || bootverbose)) 521 printf("Mount point %s had %d dangling refs\n", 522 mp->mnt_stat.f_mntonname, mp->mnt_ref); 523 if (mp->mnt_holdcnt != 0) { 524 printf("Waiting for mount point to be unheld\n"); 525 while (mp->mnt_holdcnt != 0) { 526 mp->mnt_holdcntwaiters++; 527 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 528 PZERO, "mntdestroy", 0); 529 mp->mnt_holdcntwaiters--; 530 } 531 printf("mount point unheld\n"); 532 } 533 if (mp->mnt_writeopcount > 0) { 534 printf("Waiting for mount point write ops\n"); 535 while (mp->mnt_writeopcount > 0) { 536 mp->mnt_kern_flag |= MNTK_SUSPEND; 537 msleep(&mp->mnt_writeopcount, 538 MNT_MTX(mp), 539 PZERO, "mntdestroy2", 0); 540 } 541 printf("mount point write ops completed\n"); 542 } 543 if (mp->mnt_secondary_writes > 0) { 544 printf("Waiting for mount point secondary write ops\n"); 545 while (mp->mnt_secondary_writes > 0) { 546 mp->mnt_kern_flag |= MNTK_SUSPEND; 547 msleep(&mp->mnt_secondary_writes, 548 MNT_MTX(mp), 549 PZERO, "mntdestroy3", 0); 550 } 551 printf("mount point secondary write ops completed\n"); 552 } 553 MNT_IUNLOCK(mp); 554 mp->mnt_vfc->vfc_refcount--; 555 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 556 struct vnode *vp; 557 558 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 559 vprint("", vp); 560 panic("unmount: dangling vnode"); 561 } 562 MNT_ILOCK(mp); 563 if (mp->mnt_kern_flag & MNTK_MWAIT) 564 wakeup(mp); 565 if (mp->mnt_writeopcount != 0) 566 panic("vfs_mount_destroy: nonzero writeopcount"); 567 if (mp->mnt_secondary_writes != 0) 568 panic("vfs_mount_destroy: nonzero secondary_writes"); 569 if (mp->mnt_nvnodelistsize != 0) 570 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 571 mp->mnt_writeopcount = -1000; 572 mp->mnt_nvnodelistsize = -1000; 573 mp->mnt_secondary_writes = -1000; 574 MNT_IUNLOCK(mp); 575 #ifdef MAC 576 mac_mount_destroy(mp); 577 #endif 578 if (mp->mnt_opt != NULL) 579 vfs_freeopts(mp->mnt_opt); 580 crfree(mp->mnt_cred); 581 uma_zfree(mount_zone, mp); 582 } 583 584 static int 585 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 586 { 587 struct vfsoptlist *optlist; 588 struct vfsopt *opt, *noro_opt, *tmp_opt; 589 char *fstype, *fspath, *errmsg; 590 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 591 int has_rw, has_noro; 592 593 errmsg = NULL; 594 errmsg_len = 0; 595 errmsg_pos = -1; 596 has_rw = 0; 597 has_noro = 0; 598 599 error = vfs_buildopts(fsoptions, &optlist); 600 if (error) 601 return (error); 602 603 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 604 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 605 606 /* 607 * We need these two options before the others, 608 * and they are mandatory for any filesystem. 609 * Ensure they are NUL terminated as well. 610 */ 611 fstypelen = 0; 612 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 613 if (error || fstype[fstypelen - 1] != '\0') { 614 error = EINVAL; 615 if (errmsg != NULL) 616 strncpy(errmsg, "Invalid fstype", errmsg_len); 617 goto bail; 618 } 619 fspathlen = 0; 620 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 621 if (error || fspath[fspathlen - 1] != '\0') { 622 error = EINVAL; 623 if (errmsg != NULL) 624 strncpy(errmsg, "Invalid fspath", errmsg_len); 625 goto bail; 626 } 627 628 /* 629 * We need to see if we have the "update" option 630 * before we call vfs_domount(), since vfs_domount() has special 631 * logic based on MNT_UPDATE. This is very important 632 * when we want to update the root filesystem. 633 */ 634 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 635 if (strcmp(opt->name, "update") == 0) { 636 fsflags |= MNT_UPDATE; 637 vfs_freeopt(optlist, opt); 638 } 639 else if (strcmp(opt->name, "async") == 0) 640 fsflags |= MNT_ASYNC; 641 else if (strcmp(opt->name, "force") == 0) 642 fsflags |= MNT_FORCE; 643 else if (strcmp(opt->name, "multilabel") == 0) 644 fsflags |= MNT_MULTILABEL; 645 else if (strcmp(opt->name, "noasync") == 0) 646 fsflags &= ~MNT_ASYNC; 647 else if (strcmp(opt->name, "noatime") == 0) 648 fsflags |= MNT_NOATIME; 649 else if (strcmp(opt->name, "atime") == 0) { 650 free(opt->name, M_MOUNT); 651 opt->name = strdup("nonoatime", M_MOUNT); 652 } 653 else if (strcmp(opt->name, "noclusterr") == 0) 654 fsflags |= MNT_NOCLUSTERR; 655 else if (strcmp(opt->name, "clusterr") == 0) { 656 free(opt->name, M_MOUNT); 657 opt->name = strdup("nonoclusterr", M_MOUNT); 658 } 659 else if (strcmp(opt->name, "noclusterw") == 0) 660 fsflags |= MNT_NOCLUSTERW; 661 else if (strcmp(opt->name, "clusterw") == 0) { 662 free(opt->name, M_MOUNT); 663 opt->name = strdup("nonoclusterw", M_MOUNT); 664 } 665 else if (strcmp(opt->name, "noexec") == 0) 666 fsflags |= MNT_NOEXEC; 667 else if (strcmp(opt->name, "exec") == 0) { 668 free(opt->name, M_MOUNT); 669 opt->name = strdup("nonoexec", M_MOUNT); 670 } 671 else if (strcmp(opt->name, "nosuid") == 0) 672 fsflags |= MNT_NOSUID; 673 else if (strcmp(opt->name, "suid") == 0) { 674 free(opt->name, M_MOUNT); 675 opt->name = strdup("nonosuid", M_MOUNT); 676 } 677 else if (strcmp(opt->name, "nosymfollow") == 0) 678 fsflags |= MNT_NOSYMFOLLOW; 679 else if (strcmp(opt->name, "symfollow") == 0) { 680 free(opt->name, M_MOUNT); 681 opt->name = strdup("nonosymfollow", M_MOUNT); 682 } 683 else if (strcmp(opt->name, "noro") == 0) { 684 fsflags &= ~MNT_RDONLY; 685 has_noro = 1; 686 } 687 else if (strcmp(opt->name, "rw") == 0) { 688 fsflags &= ~MNT_RDONLY; 689 has_rw = 1; 690 } 691 else if (strcmp(opt->name, "ro") == 0) 692 fsflags |= MNT_RDONLY; 693 else if (strcmp(opt->name, "rdonly") == 0) { 694 free(opt->name, M_MOUNT); 695 opt->name = strdup("ro", M_MOUNT); 696 fsflags |= MNT_RDONLY; 697 } 698 else if (strcmp(opt->name, "suiddir") == 0) 699 fsflags |= MNT_SUIDDIR; 700 else if (strcmp(opt->name, "sync") == 0) 701 fsflags |= MNT_SYNCHRONOUS; 702 else if (strcmp(opt->name, "union") == 0) 703 fsflags |= MNT_UNION; 704 } 705 706 /* 707 * If "rw" was specified as a mount option, and we 708 * are trying to update a mount-point from "ro" to "rw", 709 * we need a mount option "noro", since in vfs_mergeopts(), 710 * "noro" will cancel "ro", but "rw" will not do anything. 711 */ 712 if (has_rw && !has_noro) { 713 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 714 noro_opt->name = strdup("noro", M_MOUNT); 715 noro_opt->value = NULL; 716 noro_opt->len = 0; 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, td); 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 export_args export; 838 int error, flag = 0; 839 struct vattr va; 840 struct nameidata nd; 841 842 mtx_assert(&Giant, MA_OWNED); 843 /* 844 * Be ultra-paranoid about making sure the type and fspath 845 * variables will fit in our mp buffers, including the 846 * terminating NUL. 847 */ 848 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 849 return (ENAMETOOLONG); 850 851 if (jailed(td->td_ucred) || usermount == 0) { 852 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 853 return (error); 854 } 855 856 /* 857 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 858 */ 859 if (fsflags & MNT_EXPORTED) { 860 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 861 if (error) 862 return (error); 863 } 864 if (fsflags & MNT_SUIDDIR) { 865 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 866 if (error) 867 return (error); 868 } 869 /* 870 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 871 */ 872 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 873 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 874 fsflags |= MNT_NOSUID | MNT_USER; 875 } 876 877 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 878 vfsp = NULL; 879 if ((fsflags & MNT_UPDATE) == 0) { 880 /* Don't try to load KLDs if we're mounting the root. */ 881 if (fsflags & MNT_ROOTFS) 882 vfsp = vfs_byname(fstype); 883 else 884 vfsp = vfs_byname_kld(fstype, td, &error); 885 if (vfsp == NULL) 886 return (ENODEV); 887 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 888 return (EPERM); 889 } 890 /* 891 * Get vnode to be covered 892 */ 893 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 894 fspath, td); 895 if ((error = namei(&nd)) != 0) 896 return (error); 897 NDFREE(&nd, NDF_ONLY_PNBUF); 898 vp = nd.ni_vp; 899 if (fsflags & MNT_UPDATE) { 900 if ((vp->v_vflag & VV_ROOT) == 0) { 901 vput(vp); 902 return (EINVAL); 903 } 904 mp = vp->v_mount; 905 MNT_ILOCK(mp); 906 flag = mp->mnt_flag; 907 /* 908 * We only allow the filesystem to be reloaded if it 909 * is currently mounted read-only. 910 */ 911 if ((fsflags & MNT_RELOAD) && 912 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 913 MNT_IUNLOCK(mp); 914 vput(vp); 915 return (EOPNOTSUPP); /* Needs translation */ 916 } 917 MNT_IUNLOCK(mp); 918 /* 919 * Only privileged root, or (if MNT_USER is set) the user that 920 * did the original mount is permitted to update it. 921 */ 922 error = vfs_suser(mp, td); 923 if (error) { 924 vput(vp); 925 return (error); 926 } 927 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 928 vput(vp); 929 return (EBUSY); 930 } 931 VI_LOCK(vp); 932 if ((vp->v_iflag & VI_MOUNT) != 0 || 933 vp->v_mountedhere != NULL) { 934 VI_UNLOCK(vp); 935 vfs_unbusy(mp, td); 936 vput(vp); 937 return (EBUSY); 938 } 939 vp->v_iflag |= VI_MOUNT; 940 VI_UNLOCK(vp); 941 MNT_ILOCK(mp); 942 mp->mnt_flag |= fsflags & 943 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 944 MNT_IUNLOCK(mp); 945 VOP_UNLOCK(vp, 0); 946 mp->mnt_optnew = fsdata; 947 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 948 } else { 949 /* 950 * If the user is not root, ensure that they own the directory 951 * onto which we are attempting to mount. 952 */ 953 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 954 if (error) { 955 vput(vp); 956 return (error); 957 } 958 if (va.va_uid != td->td_ucred->cr_uid) { 959 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 960 0); 961 if (error) { 962 vput(vp); 963 return (error); 964 } 965 } 966 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 967 if (error != 0) { 968 vput(vp); 969 return (error); 970 } 971 if (vp->v_type != VDIR) { 972 vput(vp); 973 return (ENOTDIR); 974 } 975 VI_LOCK(vp); 976 if ((vp->v_iflag & VI_MOUNT) != 0 || 977 vp->v_mountedhere != NULL) { 978 VI_UNLOCK(vp); 979 vput(vp); 980 return (EBUSY); 981 } 982 vp->v_iflag |= VI_MOUNT; 983 VI_UNLOCK(vp); 984 985 /* 986 * Allocate and initialize the filesystem. 987 */ 988 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 989 VOP_UNLOCK(vp, 0); 990 991 /* XXXMAC: pass to vfs_mount_alloc? */ 992 mp->mnt_optnew = fsdata; 993 } 994 995 /* 996 * Set the mount level flags. 997 */ 998 MNT_ILOCK(mp); 999 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 1000 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 1001 MNT_RDONLY)); 1002 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1003 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1004 MNT_IUNLOCK(mp); 1005 /* 1006 * Mount the filesystem. 1007 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1008 * get. No freeing of cn_pnbuf. 1009 */ 1010 error = VFS_MOUNT(mp, td); 1011 1012 /* 1013 * Process the export option only if we are 1014 * updating mount options. 1015 */ 1016 if (!error && (fsflags & MNT_UPDATE)) { 1017 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1018 sizeof(export)) == 0) 1019 error = vfs_export(mp, &export); 1020 } 1021 1022 if (!error) { 1023 if (mp->mnt_opt != NULL) 1024 vfs_freeopts(mp->mnt_opt); 1025 mp->mnt_opt = mp->mnt_optnew; 1026 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 1027 } 1028 /* 1029 * Prevent external consumers of mount options from reading 1030 * mnt_optnew. 1031 */ 1032 mp->mnt_optnew = NULL; 1033 if (mp->mnt_flag & MNT_UPDATE) { 1034 MNT_ILOCK(mp); 1035 if (error) 1036 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1037 (flag & ~MNT_QUOTA); 1038 else 1039 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1040 MNT_FORCE | MNT_SNAPSHOT); 1041 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1042 mp->mnt_kern_flag |= MNTK_ASYNC; 1043 else 1044 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1045 MNT_IUNLOCK(mp); 1046 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1047 if (mp->mnt_syncer == NULL) 1048 error = vfs_allocate_syncvnode(mp); 1049 } else { 1050 if (mp->mnt_syncer != NULL) 1051 vrele(mp->mnt_syncer); 1052 mp->mnt_syncer = NULL; 1053 } 1054 vfs_unbusy(mp, td); 1055 VI_LOCK(vp); 1056 vp->v_iflag &= ~VI_MOUNT; 1057 VI_UNLOCK(vp); 1058 vrele(vp); 1059 return (error); 1060 } 1061 MNT_ILOCK(mp); 1062 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1063 mp->mnt_kern_flag |= MNTK_ASYNC; 1064 else 1065 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1066 MNT_IUNLOCK(mp); 1067 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1068 /* 1069 * Put the new filesystem on the mount list after root. 1070 */ 1071 cache_purge(vp); 1072 if (!error) { 1073 struct vnode *newdp; 1074 1075 VI_LOCK(vp); 1076 vp->v_iflag &= ~VI_MOUNT; 1077 VI_UNLOCK(vp); 1078 vp->v_mountedhere = mp; 1079 mtx_lock(&mountlist_mtx); 1080 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1081 mtx_unlock(&mountlist_mtx); 1082 vfs_event_signal(NULL, VQ_MOUNT, 0); 1083 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 1084 panic("mount: lost mount"); 1085 mountcheckdirs(vp, newdp); 1086 vput(newdp); 1087 VOP_UNLOCK(vp, 0); 1088 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1089 error = vfs_allocate_syncvnode(mp); 1090 vfs_unbusy(mp, td); 1091 if (error) 1092 vrele(vp); 1093 } else { 1094 VI_LOCK(vp); 1095 vp->v_iflag &= ~VI_MOUNT; 1096 VI_UNLOCK(vp); 1097 vfs_unbusy(mp, td); 1098 vfs_mount_destroy(mp); 1099 vput(vp); 1100 } 1101 return (error); 1102 } 1103 1104 /* 1105 * Unmount a filesystem. 1106 * 1107 * Note: unmount takes a path to the vnode mounted on as argument, not 1108 * special file (as before). 1109 */ 1110 #ifndef _SYS_SYSPROTO_H_ 1111 struct unmount_args { 1112 char *path; 1113 int flags; 1114 }; 1115 #endif 1116 /* ARGSUSED */ 1117 int 1118 unmount(td, uap) 1119 struct thread *td; 1120 register struct unmount_args /* { 1121 char *path; 1122 int flags; 1123 } */ *uap; 1124 { 1125 struct mount *mp; 1126 char *pathbuf; 1127 int error, id0, id1; 1128 1129 if (jailed(td->td_ucred) || usermount == 0) { 1130 error = priv_check(td, PRIV_VFS_UNMOUNT); 1131 if (error) 1132 return (error); 1133 } 1134 1135 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1136 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1137 if (error) { 1138 free(pathbuf, M_TEMP); 1139 return (error); 1140 } 1141 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1); 1142 mtx_lock(&Giant); 1143 if (uap->flags & MNT_BYFSID) { 1144 /* Decode the filesystem ID. */ 1145 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1146 mtx_unlock(&Giant); 1147 free(pathbuf, M_TEMP); 1148 return (EINVAL); 1149 } 1150 1151 mtx_lock(&mountlist_mtx); 1152 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1153 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1154 mp->mnt_stat.f_fsid.val[1] == id1) 1155 break; 1156 } 1157 mtx_unlock(&mountlist_mtx); 1158 } else { 1159 mtx_lock(&mountlist_mtx); 1160 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1161 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1162 break; 1163 } 1164 mtx_unlock(&mountlist_mtx); 1165 } 1166 free(pathbuf, M_TEMP); 1167 if (mp == NULL) { 1168 /* 1169 * Previously we returned ENOENT for a nonexistent path and 1170 * EINVAL for a non-mountpoint. We cannot tell these apart 1171 * now, so in the !MNT_BYFSID case return the more likely 1172 * EINVAL for compatibility. 1173 */ 1174 mtx_unlock(&Giant); 1175 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1176 } 1177 1178 /* 1179 * Don't allow unmounting the root filesystem. 1180 */ 1181 if (mp->mnt_flag & MNT_ROOTFS) { 1182 mtx_unlock(&Giant); 1183 return (EINVAL); 1184 } 1185 error = dounmount(mp, uap->flags, td); 1186 mtx_unlock(&Giant); 1187 return (error); 1188 } 1189 1190 /* 1191 * Do the actual filesystem unmount. 1192 */ 1193 int 1194 dounmount(mp, flags, td) 1195 struct mount *mp; 1196 int flags; 1197 struct thread *td; 1198 { 1199 struct vnode *coveredvp, *fsrootvp; 1200 int error; 1201 int async_flag; 1202 int mnt_gen_r; 1203 1204 mtx_assert(&Giant, MA_OWNED); 1205 1206 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1207 mnt_gen_r = mp->mnt_gen; 1208 VI_LOCK(coveredvp); 1209 vholdl(coveredvp); 1210 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1211 vdrop(coveredvp); 1212 /* 1213 * Check for mp being unmounted while waiting for the 1214 * covered vnode lock. 1215 */ 1216 if (coveredvp->v_mountedhere != mp || 1217 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1218 VOP_UNLOCK(coveredvp, 0); 1219 return (EBUSY); 1220 } 1221 } 1222 /* 1223 * Only privileged root, or (if MNT_USER is set) the user that did the 1224 * original mount is permitted to unmount this filesystem. 1225 */ 1226 error = vfs_suser(mp, td); 1227 if (error) { 1228 if (coveredvp) 1229 VOP_UNLOCK(coveredvp, 0); 1230 return (error); 1231 } 1232 1233 MNT_ILOCK(mp); 1234 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1235 MNT_IUNLOCK(mp); 1236 if (coveredvp) 1237 VOP_UNLOCK(coveredvp, 0); 1238 return (EBUSY); 1239 } 1240 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1241 /* Allow filesystems to detect that a forced unmount is in progress. */ 1242 if (flags & MNT_FORCE) 1243 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1244 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1245 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp)); 1246 if (error) { 1247 MNT_ILOCK(mp); 1248 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ | 1249 MNTK_UNMOUNTF); 1250 if (mp->mnt_kern_flag & MNTK_MWAIT) 1251 wakeup(mp); 1252 MNT_IUNLOCK(mp); 1253 if (coveredvp) 1254 VOP_UNLOCK(coveredvp, 0); 1255 return (error); 1256 } 1257 vn_start_write(NULL, &mp, V_WAIT); 1258 1259 if (mp->mnt_flag & MNT_EXPUBLIC) 1260 vfs_setpublicfs(NULL, NULL, NULL); 1261 1262 vfs_msync(mp, MNT_WAIT); 1263 MNT_ILOCK(mp); 1264 async_flag = mp->mnt_flag & MNT_ASYNC; 1265 mp->mnt_flag &= ~MNT_ASYNC; 1266 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1267 MNT_IUNLOCK(mp); 1268 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1269 if (mp->mnt_syncer != NULL) 1270 vrele(mp->mnt_syncer); 1271 /* 1272 * For forced unmounts, move process cdir/rdir refs on the fs root 1273 * vnode to the covered vnode. For non-forced unmounts we want 1274 * such references to cause an EBUSY error. 1275 */ 1276 if ((flags & MNT_FORCE) && 1277 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1278 if (mp->mnt_vnodecovered != NULL) 1279 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1280 if (fsrootvp == rootvnode) { 1281 vrele(rootvnode); 1282 rootvnode = NULL; 1283 } 1284 vput(fsrootvp); 1285 } 1286 if (((mp->mnt_flag & MNT_RDONLY) || 1287 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1288 (flags & MNT_FORCE)) { 1289 error = VFS_UNMOUNT(mp, flags, td); 1290 } 1291 vn_finished_write(mp); 1292 /* 1293 * If we failed to flush the dirty blocks for this mount point, 1294 * undo all the cdir/rdir and rootvnode changes we made above. 1295 * Unless we failed to do so because the device is reporting that 1296 * it doesn't exist anymore. 1297 */ 1298 if (error && error != ENXIO) { 1299 if ((flags & MNT_FORCE) && 1300 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1301 if (mp->mnt_vnodecovered != NULL) 1302 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1303 if (rootvnode == NULL) { 1304 rootvnode = fsrootvp; 1305 vref(rootvnode); 1306 } 1307 vput(fsrootvp); 1308 } 1309 MNT_ILOCK(mp); 1310 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1311 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1312 MNT_IUNLOCK(mp); 1313 (void) vfs_allocate_syncvnode(mp); 1314 MNT_ILOCK(mp); 1315 } 1316 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1317 mp->mnt_flag |= async_flag; 1318 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1319 mp->mnt_kern_flag |= MNTK_ASYNC; 1320 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL); 1321 if (mp->mnt_kern_flag & MNTK_MWAIT) 1322 wakeup(mp); 1323 MNT_IUNLOCK(mp); 1324 if (coveredvp) 1325 VOP_UNLOCK(coveredvp, 0); 1326 return (error); 1327 } 1328 mtx_lock(&mountlist_mtx); 1329 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1330 mtx_unlock(&mountlist_mtx); 1331 if (coveredvp != NULL) { 1332 coveredvp->v_mountedhere = NULL; 1333 vput(coveredvp); 1334 } 1335 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1336 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL); 1337 vfs_mount_destroy(mp); 1338 return (0); 1339 } 1340 1341 /* 1342 * --------------------------------------------------------------------- 1343 * Mounting of root filesystem 1344 * 1345 */ 1346 1347 struct root_hold_token { 1348 const char *who; 1349 LIST_ENTRY(root_hold_token) list; 1350 }; 1351 1352 static LIST_HEAD(, root_hold_token) root_holds = 1353 LIST_HEAD_INITIALIZER(&root_holds); 1354 1355 static int root_mount_complete; 1356 1357 /* 1358 * Hold root mount. 1359 */ 1360 struct root_hold_token * 1361 root_mount_hold(const char *identifier) 1362 { 1363 struct root_hold_token *h; 1364 1365 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1366 h->who = identifier; 1367 mtx_lock(&mountlist_mtx); 1368 LIST_INSERT_HEAD(&root_holds, h, list); 1369 mtx_unlock(&mountlist_mtx); 1370 return (h); 1371 } 1372 1373 /* 1374 * Release root mount. 1375 */ 1376 void 1377 root_mount_rel(struct root_hold_token *h) 1378 { 1379 1380 mtx_lock(&mountlist_mtx); 1381 LIST_REMOVE(h, list); 1382 wakeup(&root_holds); 1383 mtx_unlock(&mountlist_mtx); 1384 free(h, M_DEVBUF); 1385 } 1386 1387 /* 1388 * Wait for all subsystems to release root mount. 1389 */ 1390 static void 1391 root_mount_prepare(void) 1392 { 1393 struct root_hold_token *h; 1394 1395 for (;;) { 1396 DROP_GIANT(); 1397 g_waitidle(); 1398 PICKUP_GIANT(); 1399 mtx_lock(&mountlist_mtx); 1400 if (LIST_EMPTY(&root_holds)) { 1401 mtx_unlock(&mountlist_mtx); 1402 break; 1403 } 1404 printf("Root mount waiting for:"); 1405 LIST_FOREACH(h, &root_holds, list) 1406 printf(" %s", h->who); 1407 printf("\n"); 1408 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1409 hz); 1410 } 1411 } 1412 1413 /* 1414 * Root was mounted, share the good news. 1415 */ 1416 static void 1417 root_mount_done(void) 1418 { 1419 1420 /* 1421 * Use a mutex to prevent the wakeup being missed and waiting for 1422 * an extra 1 second sleep. 1423 */ 1424 mtx_lock(&mountlist_mtx); 1425 root_mount_complete = 1; 1426 wakeup(&root_mount_complete); 1427 mtx_unlock(&mountlist_mtx); 1428 } 1429 1430 /* 1431 * Return true if root is already mounted. 1432 */ 1433 int 1434 root_mounted(void) 1435 { 1436 1437 /* No mutex is acquired here because int stores are atomic. */ 1438 return (root_mount_complete); 1439 } 1440 1441 /* 1442 * Wait until root is mounted. 1443 */ 1444 void 1445 root_mount_wait(void) 1446 { 1447 1448 /* 1449 * Panic on an obvious deadlock - the function can't be called from 1450 * a thread which is doing the whole SYSINIT stuff. 1451 */ 1452 KASSERT(curthread->td_proc->p_pid != 0, 1453 ("root_mount_wait: cannot be called from the swapper thread")); 1454 mtx_lock(&mountlist_mtx); 1455 while (!root_mount_complete) { 1456 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1457 hz); 1458 } 1459 mtx_unlock(&mountlist_mtx); 1460 } 1461 1462 static void 1463 set_rootvnode(struct thread *td) 1464 { 1465 struct proc *p; 1466 1467 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1468 panic("Cannot find root vnode"); 1469 1470 p = td->td_proc; 1471 FILEDESC_XLOCK(p->p_fd); 1472 1473 if (p->p_fd->fd_cdir != NULL) 1474 vrele(p->p_fd->fd_cdir); 1475 p->p_fd->fd_cdir = rootvnode; 1476 VREF(rootvnode); 1477 1478 if (p->p_fd->fd_rdir != NULL) 1479 vrele(p->p_fd->fd_rdir); 1480 p->p_fd->fd_rdir = rootvnode; 1481 VREF(rootvnode); 1482 1483 FILEDESC_XUNLOCK(p->p_fd); 1484 1485 VOP_UNLOCK(rootvnode, 0); 1486 1487 EVENTHANDLER_INVOKE(mountroot); 1488 } 1489 1490 /* 1491 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1492 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1493 */ 1494 1495 static void 1496 devfs_first(void) 1497 { 1498 struct thread *td = curthread; 1499 struct vfsoptlist *opts; 1500 struct vfsconf *vfsp; 1501 struct mount *mp = NULL; 1502 int error; 1503 1504 vfsp = vfs_byname("devfs"); 1505 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1506 if (vfsp == NULL) 1507 return; 1508 1509 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1510 1511 error = VFS_MOUNT(mp, td); 1512 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1513 if (error) 1514 return; 1515 1516 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1517 TAILQ_INIT(opts); 1518 mp->mnt_opt = opts; 1519 1520 mtx_lock(&mountlist_mtx); 1521 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1522 mtx_unlock(&mountlist_mtx); 1523 1524 set_rootvnode(td); 1525 1526 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1527 if (error) 1528 printf("kern_symlink /dev -> / returns %d\n", error); 1529 } 1530 1531 /* 1532 * Surgically move our devfs to be mounted on /dev. 1533 */ 1534 1535 static void 1536 devfs_fixup(struct thread *td) 1537 { 1538 struct nameidata nd; 1539 int error; 1540 struct vnode *vp, *dvp; 1541 struct mount *mp; 1542 1543 /* Remove our devfs mount from the mountlist and purge the cache */ 1544 mtx_lock(&mountlist_mtx); 1545 mp = TAILQ_FIRST(&mountlist); 1546 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1547 mtx_unlock(&mountlist_mtx); 1548 cache_purgevfs(mp); 1549 1550 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1551 VI_LOCK(dvp); 1552 dvp->v_iflag &= ~VI_MOUNT; 1553 VI_UNLOCK(dvp); 1554 dvp->v_mountedhere = NULL; 1555 1556 /* Set up the real rootvnode, and purge the cache */ 1557 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1558 set_rootvnode(td); 1559 cache_purgevfs(rootvnode->v_mount); 1560 1561 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1562 error = namei(&nd); 1563 if (error) { 1564 printf("Lookup of /dev for devfs, error: %d\n", error); 1565 return; 1566 } 1567 NDFREE(&nd, NDF_ONLY_PNBUF); 1568 vp = nd.ni_vp; 1569 if (vp->v_type != VDIR) { 1570 vput(vp); 1571 } 1572 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1573 if (error) { 1574 vput(vp); 1575 } 1576 cache_purge(vp); 1577 mp->mnt_vnodecovered = vp; 1578 vp->v_mountedhere = mp; 1579 mtx_lock(&mountlist_mtx); 1580 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1581 mtx_unlock(&mountlist_mtx); 1582 VOP_UNLOCK(vp, 0); 1583 vput(dvp); 1584 vfs_unbusy(mp, td); 1585 1586 /* Unlink the no longer needed /dev/dev -> / symlink */ 1587 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1588 } 1589 1590 /* 1591 * Report errors during filesystem mounting. 1592 */ 1593 void 1594 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1595 { 1596 struct vfsoptlist *moptlist = mp->mnt_optnew; 1597 va_list ap; 1598 int error, len; 1599 char *errmsg; 1600 1601 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1602 if (error || errmsg == NULL || len <= 0) 1603 return; 1604 1605 va_start(ap, fmt); 1606 vsnprintf(errmsg, (size_t)len, fmt, ap); 1607 va_end(ap); 1608 } 1609 1610 /* 1611 * Find and mount the root filesystem 1612 */ 1613 void 1614 vfs_mountroot(void) 1615 { 1616 char *cp; 1617 int error, i, asked = 0; 1618 1619 root_mount_prepare(); 1620 1621 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1622 NULL, NULL, mount_init, mount_fini, 1623 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1624 devfs_first(); 1625 1626 /* 1627 * We are booted with instructions to prompt for the root filesystem. 1628 */ 1629 if (boothowto & RB_ASKNAME) { 1630 if (!vfs_mountroot_ask()) 1631 goto mounted; 1632 asked = 1; 1633 } 1634 1635 /* 1636 * The root filesystem information is compiled in, and we are 1637 * booted with instructions to use it. 1638 */ 1639 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1640 if (!vfs_mountroot_try(ctrootdevname)) 1641 goto mounted; 1642 ctrootdevname = NULL; 1643 } 1644 1645 /* 1646 * We've been given the generic "use CDROM as root" flag. This is 1647 * necessary because one media may be used in many different 1648 * devices, so we need to search for them. 1649 */ 1650 if (boothowto & RB_CDROM) { 1651 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1652 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1653 goto mounted; 1654 } 1655 } 1656 1657 /* 1658 * Try to use the value read by the loader from /etc/fstab, or 1659 * supplied via some other means. This is the preferred 1660 * mechanism. 1661 */ 1662 cp = getenv("vfs.root.mountfrom"); 1663 if (cp != NULL) { 1664 error = vfs_mountroot_try(cp); 1665 freeenv(cp); 1666 if (!error) 1667 goto mounted; 1668 } 1669 1670 /* 1671 * Try values that may have been computed by code during boot 1672 */ 1673 if (!vfs_mountroot_try(rootdevnames[0])) 1674 goto mounted; 1675 if (!vfs_mountroot_try(rootdevnames[1])) 1676 goto mounted; 1677 1678 /* 1679 * If we (still) have a compiled-in default, try it. 1680 */ 1681 if (ctrootdevname != NULL) 1682 if (!vfs_mountroot_try(ctrootdevname)) 1683 goto mounted; 1684 /* 1685 * Everything so far has failed, prompt on the console if we haven't 1686 * already tried that. 1687 */ 1688 if (!asked) 1689 if (!vfs_mountroot_ask()) 1690 goto mounted; 1691 1692 panic("Root mount failed, startup aborted."); 1693 1694 mounted: 1695 root_mount_done(); 1696 } 1697 1698 /* 1699 * Mount (mountfrom) as the root filesystem. 1700 */ 1701 static int 1702 vfs_mountroot_try(const char *mountfrom) 1703 { 1704 struct mount *mp; 1705 char *vfsname, *path; 1706 time_t timebase; 1707 int error; 1708 char patt[32]; 1709 1710 vfsname = NULL; 1711 path = NULL; 1712 mp = NULL; 1713 error = EINVAL; 1714 1715 if (mountfrom == NULL) 1716 return (error); /* don't complain */ 1717 printf("Trying to mount root from %s\n", mountfrom); 1718 1719 /* parse vfs name and path */ 1720 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1721 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1722 vfsname[0] = path[0] = 0; 1723 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1724 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1725 goto out; 1726 1727 if (path[0] == '\0') 1728 strcpy(path, ROOTNAME); 1729 1730 error = kernel_vmount( 1731 MNT_RDONLY | MNT_ROOTFS, 1732 "fstype", vfsname, 1733 "fspath", "/", 1734 "from", path, 1735 NULL); 1736 if (error == 0) { 1737 /* 1738 * We mount devfs prior to mounting the / FS, so the first 1739 * entry will typically be devfs. 1740 */ 1741 mp = TAILQ_FIRST(&mountlist); 1742 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1743 1744 /* 1745 * Iterate over all currently mounted file systems and use 1746 * the time stamp found to check and/or initialize the RTC. 1747 * Typically devfs has no time stamp and the only other FS 1748 * is the actual / FS. 1749 * Call inittodr() only once and pass it the largest of the 1750 * timestamps we encounter. 1751 */ 1752 timebase = 0; 1753 do { 1754 if (mp->mnt_time > timebase) 1755 timebase = mp->mnt_time; 1756 mp = TAILQ_NEXT(mp, mnt_list); 1757 } while (mp != NULL); 1758 inittodr(timebase); 1759 1760 devfs_fixup(curthread); 1761 } 1762 out: 1763 free(path, M_MOUNT); 1764 free(vfsname, M_MOUNT); 1765 return (error); 1766 } 1767 1768 /* 1769 * --------------------------------------------------------------------- 1770 * Interactive root filesystem selection code. 1771 */ 1772 1773 static int 1774 vfs_mountroot_ask(void) 1775 { 1776 char name[128]; 1777 1778 for(;;) { 1779 printf("\nManual root filesystem specification:\n"); 1780 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1781 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1782 printf(" eg. ufs:da0s1a\n"); 1783 #else 1784 printf(" eg. ufs:/dev/da0a\n"); 1785 #endif 1786 printf(" ? List valid disk boot devices\n"); 1787 printf(" <empty line> Abort manual input\n"); 1788 printf("\nmountroot> "); 1789 gets(name, sizeof(name), 1); 1790 if (name[0] == '\0') 1791 return (1); 1792 if (name[0] == '?') { 1793 printf("\nList of GEOM managed disk devices:\n "); 1794 g_dev_print(); 1795 continue; 1796 } 1797 if (!vfs_mountroot_try(name)) 1798 return (0); 1799 } 1800 } 1801 1802 /* 1803 * --------------------------------------------------------------------- 1804 * Functions for querying mount options/arguments from filesystems. 1805 */ 1806 1807 /* 1808 * Check that no unknown options are given 1809 */ 1810 int 1811 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1812 { 1813 struct vfsopt *opt; 1814 char errmsg[255]; 1815 const char **t, *p, *q; 1816 int ret = 0; 1817 1818 TAILQ_FOREACH(opt, opts, link) { 1819 p = opt->name; 1820 q = NULL; 1821 if (p[0] == 'n' && p[1] == 'o') 1822 q = p + 2; 1823 for(t = global_opts; *t != NULL; t++) { 1824 if (strcmp(*t, p) == 0) 1825 break; 1826 if (q != NULL) { 1827 if (strcmp(*t, q) == 0) 1828 break; 1829 } 1830 } 1831 if (*t != NULL) 1832 continue; 1833 for(t = legal; *t != NULL; t++) { 1834 if (strcmp(*t, p) == 0) 1835 break; 1836 if (q != NULL) { 1837 if (strcmp(*t, q) == 0) 1838 break; 1839 } 1840 } 1841 if (*t != NULL) 1842 continue; 1843 sprintf(errmsg, "mount option <%s> is unknown", p); 1844 printf("%s\n", errmsg); 1845 ret = EINVAL; 1846 } 1847 if (ret != 0) { 1848 TAILQ_FOREACH(opt, opts, link) { 1849 if (strcmp(opt->name, "errmsg") == 0) { 1850 strncpy((char *)opt->value, errmsg, opt->len); 1851 } 1852 } 1853 } 1854 return (ret); 1855 } 1856 1857 /* 1858 * Get a mount option by its name. 1859 * 1860 * Return 0 if the option was found, ENOENT otherwise. 1861 * If len is non-NULL it will be filled with the length 1862 * of the option. If buf is non-NULL, it will be filled 1863 * with the address of the option. 1864 */ 1865 int 1866 vfs_getopt(opts, name, buf, len) 1867 struct vfsoptlist *opts; 1868 const char *name; 1869 void **buf; 1870 int *len; 1871 { 1872 struct vfsopt *opt; 1873 1874 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1875 1876 TAILQ_FOREACH(opt, opts, link) { 1877 if (strcmp(name, opt->name) == 0) { 1878 if (len != NULL) 1879 *len = opt->len; 1880 if (buf != NULL) 1881 *buf = opt->value; 1882 return (0); 1883 } 1884 } 1885 return (ENOENT); 1886 } 1887 1888 static int 1889 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1890 { 1891 struct vfsopt *opt; 1892 int i; 1893 1894 if (opts == NULL) 1895 return (-1); 1896 1897 i = 0; 1898 TAILQ_FOREACH(opt, opts, link) { 1899 if (strcmp(name, opt->name) == 0) 1900 return (i); 1901 ++i; 1902 } 1903 return (-1); 1904 } 1905 1906 char * 1907 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1908 { 1909 struct vfsopt *opt; 1910 1911 *error = 0; 1912 TAILQ_FOREACH(opt, opts, link) { 1913 if (strcmp(name, opt->name) != 0) 1914 continue; 1915 if (((char *)opt->value)[opt->len - 1] != '\0') { 1916 *error = EINVAL; 1917 return (NULL); 1918 } 1919 return (opt->value); 1920 } 1921 *error = ENOENT; 1922 return (NULL); 1923 } 1924 1925 int 1926 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1927 { 1928 struct vfsopt *opt; 1929 1930 TAILQ_FOREACH(opt, opts, link) { 1931 if (strcmp(name, opt->name) == 0) { 1932 if (w != NULL) 1933 *w |= val; 1934 return (1); 1935 } 1936 } 1937 if (w != NULL) 1938 *w &= ~val; 1939 return (0); 1940 } 1941 1942 int 1943 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1944 { 1945 va_list ap; 1946 struct vfsopt *opt; 1947 int ret; 1948 1949 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1950 1951 TAILQ_FOREACH(opt, opts, link) { 1952 if (strcmp(name, opt->name) != 0) 1953 continue; 1954 if (opt->len == 0 || opt->value == NULL) 1955 return (0); 1956 if (((char *)opt->value)[opt->len - 1] != '\0') 1957 return (0); 1958 va_start(ap, fmt); 1959 ret = vsscanf(opt->value, fmt, ap); 1960 va_end(ap); 1961 return (ret); 1962 } 1963 return (0); 1964 } 1965 1966 /* 1967 * Find and copy a mount option. 1968 * 1969 * The size of the buffer has to be specified 1970 * in len, if it is not the same length as the 1971 * mount option, EINVAL is returned. 1972 * Returns ENOENT if the option is not found. 1973 */ 1974 int 1975 vfs_copyopt(opts, name, dest, len) 1976 struct vfsoptlist *opts; 1977 const char *name; 1978 void *dest; 1979 int len; 1980 { 1981 struct vfsopt *opt; 1982 1983 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1984 1985 TAILQ_FOREACH(opt, opts, link) { 1986 if (strcmp(name, opt->name) == 0) { 1987 if (len != opt->len) 1988 return (EINVAL); 1989 bcopy(opt->value, dest, opt->len); 1990 return (0); 1991 } 1992 } 1993 return (ENOENT); 1994 } 1995 1996 /* 1997 * This is a helper function for filesystems to traverse their 1998 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1999 */ 2000 2001 struct vnode * 2002 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 2003 { 2004 struct vnode *vp; 2005 2006 mtx_assert(MNT_MTX(mp), MA_OWNED); 2007 2008 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2009 if ((*mvp)->v_yield++ == 500) { 2010 MNT_IUNLOCK(mp); 2011 (*mvp)->v_yield = 0; 2012 uio_yield(); 2013 MNT_ILOCK(mp); 2014 } 2015 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 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 __mnt_vnode_markerfree(mvp, mp); 2022 return (NULL); 2023 } 2024 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2025 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2026 return (vp); 2027 } 2028 2029 struct vnode * 2030 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2031 { 2032 struct vnode *vp; 2033 2034 mtx_assert(MNT_MTX(mp), MA_OWNED); 2035 2036 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2037 while (vp != NULL && vp->v_type == VMARKER) 2038 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2039 2040 /* Check if we are done */ 2041 if (vp == NULL) { 2042 *mvp = NULL; 2043 return (NULL); 2044 } 2045 mp->mnt_holdcnt++; 2046 MNT_IUNLOCK(mp); 2047 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2048 M_VNODE_MARKER, 2049 M_WAITOK | M_ZERO); 2050 MNT_ILOCK(mp); 2051 (*mvp)->v_type = VMARKER; 2052 2053 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2054 while (vp != NULL && vp->v_type == VMARKER) 2055 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2056 2057 /* Check if we are done */ 2058 if (vp == NULL) { 2059 MNT_IUNLOCK(mp); 2060 free(*mvp, M_VNODE_MARKER); 2061 MNT_ILOCK(mp); 2062 *mvp = NULL; 2063 mp->mnt_holdcnt--; 2064 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2065 wakeup(&mp->mnt_holdcnt); 2066 return (NULL); 2067 } 2068 mp->mnt_markercnt++; 2069 (*mvp)->v_mount = mp; 2070 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2071 return (vp); 2072 } 2073 2074 2075 void 2076 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2077 { 2078 2079 if (*mvp == NULL) 2080 return; 2081 2082 mtx_assert(MNT_MTX(mp), MA_OWNED); 2083 2084 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2085 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2086 MNT_IUNLOCK(mp); 2087 free(*mvp, M_VNODE_MARKER); 2088 MNT_ILOCK(mp); 2089 *mvp = NULL; 2090 2091 mp->mnt_markercnt--; 2092 mp->mnt_holdcnt--; 2093 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2094 wakeup(&mp->mnt_holdcnt); 2095 } 2096 2097 2098 int 2099 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 2100 { 2101 int error; 2102 2103 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 2104 if (sbp != &mp->mnt_stat) 2105 *sbp = mp->mnt_stat; 2106 return (error); 2107 } 2108 2109 void 2110 vfs_mountedfrom(struct mount *mp, const char *from) 2111 { 2112 2113 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2114 strlcpy(mp->mnt_stat.f_mntfromname, from, 2115 sizeof mp->mnt_stat.f_mntfromname); 2116 } 2117 2118 /* 2119 * --------------------------------------------------------------------- 2120 * This is the api for building mount args and mounting filesystems from 2121 * inside the kernel. 2122 * 2123 * The API works by accumulation of individual args. First error is 2124 * latched. 2125 * 2126 * XXX: should be documented in new manpage kernel_mount(9) 2127 */ 2128 2129 /* A memory allocation which must be freed when we are done */ 2130 struct mntaarg { 2131 SLIST_ENTRY(mntaarg) next; 2132 }; 2133 2134 /* The header for the mount arguments */ 2135 struct mntarg { 2136 struct iovec *v; 2137 int len; 2138 int error; 2139 SLIST_HEAD(, mntaarg) list; 2140 }; 2141 2142 /* 2143 * Add a boolean argument. 2144 * 2145 * flag is the boolean value. 2146 * name must start with "no". 2147 */ 2148 struct mntarg * 2149 mount_argb(struct mntarg *ma, int flag, const char *name) 2150 { 2151 2152 KASSERT(name[0] == 'n' && name[1] == 'o', 2153 ("mount_argb(...,%s): name must start with 'no'", name)); 2154 2155 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2156 } 2157 2158 /* 2159 * Add an argument printf style 2160 */ 2161 struct mntarg * 2162 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2163 { 2164 va_list ap; 2165 struct mntaarg *maa; 2166 struct sbuf *sb; 2167 int len; 2168 2169 if (ma == NULL) { 2170 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2171 SLIST_INIT(&ma->list); 2172 } 2173 if (ma->error) 2174 return (ma); 2175 2176 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2177 M_MOUNT, M_WAITOK); 2178 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2179 ma->v[ma->len].iov_len = strlen(name) + 1; 2180 ma->len++; 2181 2182 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 2183 va_start(ap, fmt); 2184 sbuf_vprintf(sb, fmt, ap); 2185 va_end(ap); 2186 sbuf_finish(sb); 2187 len = sbuf_len(sb) + 1; 2188 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2189 SLIST_INSERT_HEAD(&ma->list, maa, next); 2190 bcopy(sbuf_data(sb), maa + 1, len); 2191 sbuf_delete(sb); 2192 2193 ma->v[ma->len].iov_base = maa + 1; 2194 ma->v[ma->len].iov_len = len; 2195 ma->len++; 2196 2197 return (ma); 2198 } 2199 2200 /* 2201 * Add an argument which is a userland string. 2202 */ 2203 struct mntarg * 2204 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2205 { 2206 struct mntaarg *maa; 2207 char *tbuf; 2208 2209 if (val == NULL) 2210 return (ma); 2211 if (ma == NULL) { 2212 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2213 SLIST_INIT(&ma->list); 2214 } 2215 if (ma->error) 2216 return (ma); 2217 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2218 SLIST_INSERT_HEAD(&ma->list, maa, next); 2219 tbuf = (void *)(maa + 1); 2220 ma->error = copyinstr(val, tbuf, len, NULL); 2221 return (mount_arg(ma, name, tbuf, -1)); 2222 } 2223 2224 /* 2225 * Plain argument. 2226 * 2227 * If length is -1, treat value as a C string. 2228 */ 2229 struct mntarg * 2230 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2231 { 2232 2233 if (ma == NULL) { 2234 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2235 SLIST_INIT(&ma->list); 2236 } 2237 if (ma->error) 2238 return (ma); 2239 2240 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2241 M_MOUNT, M_WAITOK); 2242 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2243 ma->v[ma->len].iov_len = strlen(name) + 1; 2244 ma->len++; 2245 2246 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2247 if (len < 0) 2248 ma->v[ma->len].iov_len = strlen(val) + 1; 2249 else 2250 ma->v[ma->len].iov_len = len; 2251 ma->len++; 2252 return (ma); 2253 } 2254 2255 /* 2256 * Free a mntarg structure 2257 */ 2258 static void 2259 free_mntarg(struct mntarg *ma) 2260 { 2261 struct mntaarg *maa; 2262 2263 while (!SLIST_EMPTY(&ma->list)) { 2264 maa = SLIST_FIRST(&ma->list); 2265 SLIST_REMOVE_HEAD(&ma->list, next); 2266 free(maa, M_MOUNT); 2267 } 2268 free(ma->v, M_MOUNT); 2269 free(ma, M_MOUNT); 2270 } 2271 2272 /* 2273 * Mount a filesystem 2274 */ 2275 int 2276 kernel_mount(struct mntarg *ma, int flags) 2277 { 2278 struct uio auio; 2279 int error; 2280 2281 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2282 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2283 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2284 2285 auio.uio_iov = ma->v; 2286 auio.uio_iovcnt = ma->len; 2287 auio.uio_segflg = UIO_SYSSPACE; 2288 2289 error = ma->error; 2290 if (!error) 2291 error = vfs_donmount(curthread, flags, &auio); 2292 free_mntarg(ma); 2293 return (error); 2294 } 2295 2296 /* 2297 * A printflike function to mount a filesystem. 2298 */ 2299 int 2300 kernel_vmount(int flags, ...) 2301 { 2302 struct mntarg *ma = NULL; 2303 va_list ap; 2304 const char *cp; 2305 const void *vp; 2306 int error; 2307 2308 va_start(ap, flags); 2309 for (;;) { 2310 cp = va_arg(ap, const char *); 2311 if (cp == NULL) 2312 break; 2313 vp = va_arg(ap, const void *); 2314 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2315 } 2316 va_end(ap); 2317 2318 error = kernel_mount(ma, flags); 2319 return (error); 2320 } 2321