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