Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_mount.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1999 Michael Smith 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/conf.h> 42 #include <sys/clock.h> 43 #include <sys/jail.h> 44 #include <sys/kernel.h> 45 #include <sys/libkern.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/namei.h> 50 #include <sys/priv.h> 51 #include <sys/proc.h> 52 #include <sys/filedesc.h> 53 #include <sys/reboot.h> 54 #include <sys/syscallsubr.h> 55 #include <sys/sysproto.h> 56 #include <sys/sx.h> 57 #include <sys/sysctl.h> 58 #include <sys/sysent.h> 59 #include <sys/systm.h> 60 #include <sys/vnode.h> 61 #include <vm/uma.h> 62 63 #include <geom/geom.h> 64 65 #include <machine/stdarg.h> 66 67 #include <security/audit/audit.h> 68 #include <security/mac/mac_framework.h> 69 70 #include "opt_rootdevname.h" 71 #include "opt_ddb.h" 72 #include "opt_mac.h" 73 74 #ifdef DDB 75 #include <ddb/ddb.h> 76 #endif 77 78 #define ROOTNAME "root_device" 79 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 80 81 static int vfs_domount(struct thread *td, const char *fstype, 82 char *fspath, int fsflags, void *fsdata); 83 static int vfs_mountroot_ask(void); 84 static int vfs_mountroot_try(const char *mountfrom); 85 static void free_mntarg(struct mntarg *ma); 86 static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 87 88 static int usermount = 0; 89 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 90 "Unprivileged users may mount and unmount file systems"); 91 92 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 93 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 94 static uma_zone_t mount_zone; 95 96 /* List of mounted filesystems. */ 97 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 98 99 /* For any iteration/modification of mountlist */ 100 struct mtx mountlist_mtx; 101 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 102 103 TAILQ_HEAD(vfsoptlist, vfsopt); 104 struct vfsopt { 105 TAILQ_ENTRY(vfsopt) link; 106 char *name; 107 void *value; 108 int len; 109 }; 110 111 /* 112 * The vnode of the system's root (/ in the filesystem, without chroot 113 * active.) 114 */ 115 struct vnode *rootvnode; 116 117 /* 118 * The root filesystem is detailed in the kernel environment variable 119 * vfs.root.mountfrom, which is expected to be in the general format 120 * 121 * <vfsname>:[<path>] 122 * vfsname := the name of a VFS known to the kernel and capable 123 * of being mounted as root 124 * path := disk device name or other data used by the filesystem 125 * to locate its physical store 126 */ 127 128 /* 129 * Global opts, taken by all filesystems 130 */ 131 static const char *global_opts[] = { 132 "errmsg", 133 "fstype", 134 "fspath", 135 "ro", 136 "rw", 137 "nosuid", 138 "noexec", 139 NULL 140 }; 141 142 /* 143 * The root specifiers we will try if RB_CDROM is specified. 144 */ 145 static char *cdrom_rootdevnames[] = { 146 "cd9660:cd0", 147 "cd9660:acd0", 148 NULL 149 }; 150 151 /* legacy find-root code */ 152 char *rootdevnames[2] = {NULL, NULL}; 153 #ifndef ROOTDEVNAME 154 # define ROOTDEVNAME NULL 155 #endif 156 static const char *ctrootdevname = ROOTDEVNAME; 157 158 /* 159 * --------------------------------------------------------------------- 160 * Functions for building and sanitizing the mount options 161 */ 162 163 /* Remove one mount option. */ 164 static void 165 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 166 { 167 168 TAILQ_REMOVE(opts, opt, link); 169 free(opt->name, M_MOUNT); 170 if (opt->value != NULL) 171 free(opt->value, M_MOUNT); 172 #ifdef INVARIANTS 173 else if (opt->len != 0) 174 panic("%s: mount option with NULL value but length != 0", 175 __func__); 176 #endif 177 free(opt, M_MOUNT); 178 } 179 180 /* Release all resources related to the mount options. */ 181 void 182 vfs_freeopts(struct vfsoptlist *opts) 183 { 184 struct vfsopt *opt; 185 186 while (!TAILQ_EMPTY(opts)) { 187 opt = TAILQ_FIRST(opts); 188 vfs_freeopt(opts, opt); 189 } 190 free(opts, M_MOUNT); 191 } 192 193 void 194 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 195 { 196 struct vfsopt *opt, *temp; 197 198 if (opts == NULL) 199 return; 200 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 201 if (strcmp(opt->name, name) == 0) 202 vfs_freeopt(opts, opt); 203 } 204 } 205 206 /* 207 * Check if options are equal (with or without the "no" prefix). 208 */ 209 static int 210 vfs_equalopts(const char *opt1, const char *opt2) 211 { 212 213 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 214 if (strcmp(opt1, opt2) == 0) 215 return (1); 216 /* "noopt" vs. "opt" */ 217 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 218 return (1); 219 /* "opt" vs. "noopt" */ 220 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 221 return (1); 222 return (0); 223 } 224 225 /* 226 * If a mount option is specified several times, 227 * (with or without the "no" prefix) only keep 228 * the last occurence of it. 229 */ 230 static void 231 vfs_sanitizeopts(struct vfsoptlist *opts) 232 { 233 struct vfsopt *opt, *opt2, *tmp; 234 235 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 236 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 237 while (opt2 != NULL) { 238 if (vfs_equalopts(opt->name, opt2->name)) { 239 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 240 vfs_freeopt(opts, opt2); 241 opt2 = tmp; 242 } else { 243 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 244 } 245 } 246 } 247 } 248 249 /* 250 * Build a linked list of mount options from a struct uio. 251 */ 252 static int 253 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 254 { 255 struct vfsoptlist *opts; 256 struct vfsopt *opt; 257 size_t memused; 258 unsigned int i, iovcnt; 259 int error, namelen, optlen; 260 261 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 262 TAILQ_INIT(opts); 263 memused = 0; 264 iovcnt = auio->uio_iovcnt; 265 for (i = 0; i < iovcnt; i += 2) { 266 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 267 namelen = auio->uio_iov[i].iov_len; 268 optlen = auio->uio_iov[i + 1].iov_len; 269 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 270 opt->value = NULL; 271 opt->len = 0; 272 273 /* 274 * Do this early, so jumps to "bad" will free the current 275 * option. 276 */ 277 TAILQ_INSERT_TAIL(opts, opt, link); 278 memused += sizeof(struct vfsopt) + optlen + namelen; 279 280 /* 281 * Avoid consuming too much memory, and attempts to overflow 282 * memused. 283 */ 284 if (memused > VFS_MOUNTARG_SIZE_MAX || 285 optlen > VFS_MOUNTARG_SIZE_MAX || 286 namelen > VFS_MOUNTARG_SIZE_MAX) { 287 error = EINVAL; 288 goto bad; 289 } 290 291 if (auio->uio_segflg == UIO_SYSSPACE) { 292 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 293 } else { 294 error = copyin(auio->uio_iov[i].iov_base, opt->name, 295 namelen); 296 if (error) 297 goto bad; 298 } 299 /* Ensure names are null-terminated strings. */ 300 if (opt->name[namelen - 1] != '\0') { 301 error = EINVAL; 302 goto bad; 303 } 304 if (optlen != 0) { 305 opt->len = optlen; 306 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 307 if (auio->uio_segflg == UIO_SYSSPACE) { 308 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 309 optlen); 310 } else { 311 error = copyin(auio->uio_iov[i + 1].iov_base, 312 opt->value, optlen); 313 if (error) 314 goto bad; 315 } 316 } 317 } 318 vfs_sanitizeopts(opts); 319 *options = opts; 320 return (0); 321 bad: 322 vfs_freeopts(opts); 323 return (error); 324 } 325 326 /* 327 * Merge the old mount options with the new ones passed 328 * in the MNT_UPDATE case. 329 */ 330 static void 331 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 332 { 333 struct vfsopt *opt, *opt2, *new; 334 335 TAILQ_FOREACH(opt, opts, link) { 336 /* 337 * Check that this option hasn't been redefined 338 * nor cancelled with a "no" mount option. 339 */ 340 opt2 = TAILQ_FIRST(toopts); 341 while (opt2 != NULL) { 342 if (strcmp(opt2->name, opt->name) == 0) 343 goto next; 344 if (strncmp(opt2->name, "no", 2) == 0 && 345 strcmp(opt2->name + 2, opt->name) == 0) { 346 vfs_freeopt(toopts, opt2); 347 goto next; 348 } 349 opt2 = TAILQ_NEXT(opt2, link); 350 } 351 /* We want this option, duplicate it. */ 352 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 353 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 354 strcpy(new->name, opt->name); 355 if (opt->len != 0) { 356 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 357 bcopy(opt->value, new->value, opt->len); 358 } else { 359 new->value = NULL; 360 } 361 new->len = opt->len; 362 TAILQ_INSERT_TAIL(toopts, new, link); 363 next: 364 continue; 365 } 366 } 367 368 /* 369 * Mount a filesystem. 370 */ 371 int 372 nmount(td, uap) 373 struct thread *td; 374 struct nmount_args /* { 375 struct iovec *iovp; 376 unsigned int iovcnt; 377 int flags; 378 } */ *uap; 379 { 380 struct uio *auio; 381 struct iovec *iov; 382 unsigned int i; 383 int error; 384 u_int iovcnt; 385 386 AUDIT_ARG(fflags, uap->flags); 387 388 /* 389 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 390 * userspace to set this flag, but we must filter it out if we want 391 * MNT_UPDATE on the root file system to work. 392 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 393 */ 394 uap->flags &= ~MNT_ROOTFS; 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 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 453 return (0); 454 } 455 456 static void 457 mount_fini(void *mem, int size) 458 { 459 struct mount *mp; 460 461 mp = (struct mount *)mem; 462 lockdestroy(&mp->mnt_explock); 463 lockdestroy(&mp->mnt_lock); 464 mtx_destroy(&mp->mnt_mtx); 465 } 466 467 /* 468 * Allocate and initialize the mount point struct. 469 */ 470 struct mount * 471 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 472 const char *fspath, struct thread *td) 473 { 474 struct mount *mp; 475 476 mp = uma_zalloc(mount_zone, M_WAITOK); 477 bzero(&mp->mnt_startzero, 478 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 479 TAILQ_INIT(&mp->mnt_nvnodelist); 480 mp->mnt_nvnodelistsize = 0; 481 mp->mnt_ref = 0; 482 (void) vfs_busy(mp, LK_NOWAIT, 0, td); 483 mp->mnt_op = vfsp->vfc_vfsops; 484 mp->mnt_vfc = vfsp; 485 vfsp->vfc_refcount++; /* XXX Unlocked */ 486 mp->mnt_stat.f_type = vfsp->vfc_typenum; 487 mp->mnt_gen++; 488 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 489 mp->mnt_vnodecovered = vp; 490 mp->mnt_cred = crdup(td->td_ucred); 491 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 492 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 493 mp->mnt_iosize_max = DFLTPHYS; 494 #ifdef MAC 495 mac_init_mount(mp); 496 mac_create_mount(td->td_ucred, mp); 497 #endif 498 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 499 return (mp); 500 } 501 502 /* 503 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 504 */ 505 void 506 vfs_mount_destroy(struct mount *mp) 507 { 508 int i; 509 510 MNT_ILOCK(mp); 511 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 512 if (mp->mnt_kern_flag & MNTK_MWAIT) { 513 mp->mnt_kern_flag &= ~MNTK_MWAIT; 514 wakeup(mp); 515 } 516 for (i = 0; mp->mnt_ref && i < 3; i++) 517 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 518 /* 519 * This will always cause a 3 second delay in rebooting due to 520 * refs on the root mountpoint that never go away. Most of these 521 * are held by init which never exits. 522 */ 523 if (i == 3 && (!rebooting || bootverbose)) 524 printf("Mount point %s had %d dangling refs\n", 525 mp->mnt_stat.f_mntonname, mp->mnt_ref); 526 if (mp->mnt_holdcnt != 0) { 527 printf("Waiting for mount point to be unheld\n"); 528 while (mp->mnt_holdcnt != 0) { 529 mp->mnt_holdcntwaiters++; 530 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 531 PZERO, "mntdestroy", 0); 532 mp->mnt_holdcntwaiters--; 533 } 534 printf("mount point unheld\n"); 535 } 536 if (mp->mnt_writeopcount > 0) { 537 printf("Waiting for mount point write ops\n"); 538 while (mp->mnt_writeopcount > 0) { 539 mp->mnt_kern_flag |= MNTK_SUSPEND; 540 msleep(&mp->mnt_writeopcount, 541 MNT_MTX(mp), 542 PZERO, "mntdestroy2", 0); 543 } 544 printf("mount point write ops completed\n"); 545 } 546 if (mp->mnt_secondary_writes > 0) { 547 printf("Waiting for mount point secondary write ops\n"); 548 while (mp->mnt_secondary_writes > 0) { 549 mp->mnt_kern_flag |= MNTK_SUSPEND; 550 msleep(&mp->mnt_secondary_writes, 551 MNT_MTX(mp), 552 PZERO, "mntdestroy3", 0); 553 } 554 printf("mount point secondary write ops completed\n"); 555 } 556 MNT_IUNLOCK(mp); 557 mp->mnt_vfc->vfc_refcount--; 558 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 559 struct vnode *vp; 560 561 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 562 vprint("", vp); 563 panic("unmount: dangling vnode"); 564 } 565 MNT_ILOCK(mp); 566 if (mp->mnt_kern_flag & MNTK_MWAIT) 567 wakeup(mp); 568 if (mp->mnt_writeopcount != 0) 569 panic("vfs_mount_destroy: nonzero writeopcount"); 570 if (mp->mnt_secondary_writes != 0) 571 panic("vfs_mount_destroy: nonzero secondary_writes"); 572 if (mp->mnt_nvnodelistsize != 0) 573 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 574 mp->mnt_writeopcount = -1000; 575 mp->mnt_nvnodelistsize = -1000; 576 mp->mnt_secondary_writes = -1000; 577 MNT_IUNLOCK(mp); 578 #ifdef MAC 579 mac_destroy_mount(mp); 580 #endif 581 if (mp->mnt_opt != NULL) 582 vfs_freeopts(mp->mnt_opt); 583 crfree(mp->mnt_cred); 584 uma_zfree(mount_zone, mp); 585 } 586 587 int 588 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 589 { 590 struct vfsoptlist *optlist; 591 struct vfsopt *opt, *noro_opt, *tmp_opt; 592 char *fstype, *fspath, *errmsg; 593 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 594 int has_rw, has_noro; 595 596 errmsg = NULL; 597 errmsg_len = 0; 598 errmsg_pos = -1; 599 has_rw = 0; 600 has_noro = 0; 601 602 error = vfs_buildopts(fsoptions, &optlist); 603 if (error) 604 return (error); 605 606 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 607 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 608 609 /* 610 * We need these two options before the others, 611 * and they are mandatory for any filesystem. 612 * Ensure they are NUL terminated as well. 613 */ 614 fstypelen = 0; 615 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 616 if (error || fstype[fstypelen - 1] != '\0') { 617 error = EINVAL; 618 if (errmsg != NULL) 619 strncpy(errmsg, "Invalid fstype", errmsg_len); 620 goto bail; 621 } 622 fspathlen = 0; 623 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 624 if (error || fspath[fspathlen - 1] != '\0') { 625 error = EINVAL; 626 if (errmsg != NULL) 627 strncpy(errmsg, "Invalid fspath", errmsg_len); 628 goto bail; 629 } 630 631 /* 632 * We need to see if we have the "update" option 633 * before we call vfs_domount(), since vfs_domount() has special 634 * logic based on MNT_UPDATE. This is very important 635 * when we want to update the root filesystem. 636 */ 637 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 638 if (strcmp(opt->name, "update") == 0) { 639 fsflags |= MNT_UPDATE; 640 vfs_freeopt(optlist, opt); 641 } 642 else if (strcmp(opt->name, "async") == 0) 643 fsflags |= MNT_ASYNC; 644 else if (strcmp(opt->name, "force") == 0) { 645 fsflags |= MNT_FORCE; 646 vfs_freeopt(optlist, opt); 647 } 648 else if (strcmp(opt->name, "reload") == 0) { 649 fsflags |= MNT_RELOAD; 650 vfs_freeopt(optlist, opt); 651 } 652 else if (strcmp(opt->name, "multilabel") == 0) 653 fsflags |= MNT_MULTILABEL; 654 else if (strcmp(opt->name, "noasync") == 0) 655 fsflags &= ~MNT_ASYNC; 656 else if (strcmp(opt->name, "noatime") == 0) 657 fsflags |= MNT_NOATIME; 658 else if (strcmp(opt->name, "atime") == 0) { 659 free(opt->name, M_MOUNT); 660 opt->name = strdup("nonoatime", M_MOUNT); 661 } 662 else if (strcmp(opt->name, "noclusterr") == 0) 663 fsflags |= MNT_NOCLUSTERR; 664 else if (strcmp(opt->name, "clusterr") == 0) { 665 free(opt->name, M_MOUNT); 666 opt->name = strdup("nonoclusterr", M_MOUNT); 667 } 668 else if (strcmp(opt->name, "noclusterw") == 0) 669 fsflags |= MNT_NOCLUSTERW; 670 else if (strcmp(opt->name, "clusterw") == 0) { 671 free(opt->name, M_MOUNT); 672 opt->name = strdup("nonoclusterw", M_MOUNT); 673 } 674 else if (strcmp(opt->name, "noexec") == 0) 675 fsflags |= MNT_NOEXEC; 676 else if (strcmp(opt->name, "exec") == 0) { 677 free(opt->name, M_MOUNT); 678 opt->name = strdup("nonoexec", M_MOUNT); 679 } 680 else if (strcmp(opt->name, "nosuid") == 0) 681 fsflags |= MNT_NOSUID; 682 else if (strcmp(opt->name, "suid") == 0) { 683 free(opt->name, M_MOUNT); 684 opt->name = strdup("nonosuid", M_MOUNT); 685 } 686 else if (strcmp(opt->name, "nosymfollow") == 0) 687 fsflags |= MNT_NOSYMFOLLOW; 688 else if (strcmp(opt->name, "symfollow") == 0) { 689 free(opt->name, M_MOUNT); 690 opt->name = strdup("nonosymfollow", M_MOUNT); 691 } 692 else if (strcmp(opt->name, "noro") == 0) { 693 fsflags &= ~MNT_RDONLY; 694 has_noro = 1; 695 } 696 else if (strcmp(opt->name, "rw") == 0) { 697 fsflags &= ~MNT_RDONLY; 698 has_rw = 1; 699 } 700 else if (strcmp(opt->name, "ro") == 0) 701 fsflags |= MNT_RDONLY; 702 else if (strcmp(opt->name, "rdonly") == 0) { 703 free(opt->name, M_MOUNT); 704 opt->name = strdup("ro", M_MOUNT); 705 fsflags |= MNT_RDONLY; 706 } 707 else if (strcmp(opt->name, "suiddir") == 0) 708 fsflags |= MNT_SUIDDIR; 709 else if (strcmp(opt->name, "sync") == 0) 710 fsflags |= MNT_SYNCHRONOUS; 711 else if (strcmp(opt->name, "union") == 0) 712 fsflags |= MNT_UNION; 713 } 714 715 /* 716 * If "rw" was specified as a mount option, and we 717 * are trying to update a mount-point from "ro" to "rw", 718 * we need a mount option "noro", since in vfs_mergeopts(), 719 * "noro" will cancel "ro", but "rw" will not do anything. 720 */ 721 if (has_rw && !has_noro) { 722 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 723 noro_opt->name = strdup("noro", M_MOUNT); 724 noro_opt->value = NULL; 725 noro_opt->len = 0; 726 TAILQ_INSERT_TAIL(optlist, noro_opt, link); 727 } 728 729 /* 730 * Be ultra-paranoid about making sure the type and fspath 731 * variables will fit in our mp buffers, including the 732 * terminating NUL. 733 */ 734 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 735 error = ENAMETOOLONG; 736 goto bail; 737 } 738 739 mtx_lock(&Giant); 740 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 741 mtx_unlock(&Giant); 742 bail: 743 /* copyout the errmsg */ 744 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 745 && errmsg_len > 0 && errmsg != NULL) { 746 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 747 bcopy(errmsg, 748 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 749 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 750 } else { 751 copyout(errmsg, 752 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 753 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 754 } 755 } 756 757 if (error != 0) 758 vfs_freeopts(optlist); 759 return (error); 760 } 761 762 /* 763 * Old mount API. 764 */ 765 #ifndef _SYS_SYSPROTO_H_ 766 struct mount_args { 767 char *type; 768 char *path; 769 int flags; 770 caddr_t data; 771 }; 772 #endif 773 /* ARGSUSED */ 774 int 775 mount(td, uap) 776 struct thread *td; 777 struct mount_args /* { 778 char *type; 779 char *path; 780 int flags; 781 caddr_t data; 782 } */ *uap; 783 { 784 char *fstype; 785 struct vfsconf *vfsp = NULL; 786 struct mntarg *ma = NULL; 787 int error; 788 789 AUDIT_ARG(fflags, uap->flags); 790 791 /* 792 * Filter out MNT_ROOTFS. We do not want clients of mount() in 793 * userspace to set this flag, but we must filter it out if we want 794 * MNT_UPDATE on the root file system to work. 795 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 796 */ 797 uap->flags &= ~MNT_ROOTFS; 798 799 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 800 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 801 if (error) { 802 free(fstype, M_TEMP); 803 return (error); 804 } 805 806 AUDIT_ARG(text, fstype); 807 mtx_lock(&Giant); 808 vfsp = vfs_byname_kld(fstype, td, &error); 809 free(fstype, M_TEMP); 810 if (vfsp == NULL) { 811 mtx_unlock(&Giant); 812 return (ENOENT); 813 } 814 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 815 mtx_unlock(&Giant); 816 return (EOPNOTSUPP); 817 } 818 819 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 820 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 821 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 822 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 823 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 824 825 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 826 mtx_unlock(&Giant); 827 return (error); 828 } 829 830 831 /* 832 * vfs_domount(): actually attempt a filesystem mount. 833 */ 834 static int 835 vfs_domount( 836 struct thread *td, /* Calling thread. */ 837 const char *fstype, /* Filesystem type. */ 838 char *fspath, /* Mount path. */ 839 int fsflags, /* Flags common to all filesystems. */ 840 void *fsdata /* Options local to the filesystem. */ 841 ) 842 { 843 struct vnode *vp; 844 struct mount *mp; 845 struct vfsconf *vfsp; 846 struct export_args export; 847 int error, flag = 0; 848 struct vattr va; 849 struct nameidata nd; 850 851 mtx_assert(&Giant, MA_OWNED); 852 /* 853 * Be ultra-paranoid about making sure the type and fspath 854 * variables will fit in our mp buffers, including the 855 * terminating NUL. 856 */ 857 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 858 return (ENAMETOOLONG); 859 860 if (jailed(td->td_ucred) || usermount == 0) { 861 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 862 return (error); 863 } 864 865 /* 866 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 867 */ 868 if (fsflags & MNT_EXPORTED) { 869 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 870 if (error) 871 return (error); 872 } 873 if (fsflags & MNT_SUIDDIR) { 874 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 875 if (error) 876 return (error); 877 } 878 /* 879 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 880 */ 881 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 882 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 883 fsflags |= MNT_NOSUID | MNT_USER; 884 } 885 886 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 887 vfsp = NULL; 888 if ((fsflags & MNT_UPDATE) == 0) { 889 /* Don't try to load KLDs if we're mounting the root. */ 890 if (fsflags & MNT_ROOTFS) 891 vfsp = vfs_byname(fstype); 892 else 893 vfsp = vfs_byname_kld(fstype, td, &error); 894 if (vfsp == NULL) 895 return (ENODEV); 896 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 897 return (EPERM); 898 } 899 /* 900 * Get vnode to be covered 901 */ 902 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 903 fspath, td); 904 if ((error = namei(&nd)) != 0) 905 return (error); 906 NDFREE(&nd, NDF_ONLY_PNBUF); 907 vp = nd.ni_vp; 908 if (fsflags & MNT_UPDATE) { 909 if ((vp->v_vflag & VV_ROOT) == 0) { 910 vput(vp); 911 return (EINVAL); 912 } 913 mp = vp->v_mount; 914 MNT_ILOCK(mp); 915 flag = mp->mnt_flag; 916 /* 917 * We only allow the filesystem to be reloaded if it 918 * is currently mounted read-only. 919 */ 920 if ((fsflags & MNT_RELOAD) && 921 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 922 MNT_IUNLOCK(mp); 923 vput(vp); 924 return (EOPNOTSUPP); /* Needs translation */ 925 } 926 MNT_IUNLOCK(mp); 927 /* 928 * Only privileged root, or (if MNT_USER is set) the user that 929 * did the original mount is permitted to update it. 930 */ 931 error = vfs_suser(mp, td); 932 if (error) { 933 vput(vp); 934 return (error); 935 } 936 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 937 vput(vp); 938 return (EBUSY); 939 } 940 VI_LOCK(vp); 941 if ((vp->v_iflag & VI_MOUNT) != 0 || 942 vp->v_mountedhere != NULL) { 943 VI_UNLOCK(vp); 944 vfs_unbusy(mp, td); 945 vput(vp); 946 return (EBUSY); 947 } 948 vp->v_iflag |= VI_MOUNT; 949 VI_UNLOCK(vp); 950 MNT_ILOCK(mp); 951 mp->mnt_flag |= fsflags & 952 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 953 MNT_IUNLOCK(mp); 954 VOP_UNLOCK(vp, 0, td); 955 mp->mnt_optnew = fsdata; 956 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 957 } else { 958 /* 959 * If the user is not root, ensure that they own the directory 960 * onto which we are attempting to mount. 961 */ 962 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 963 if (error) { 964 vput(vp); 965 return (error); 966 } 967 if (va.va_uid != td->td_ucred->cr_uid) { 968 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 969 0); 970 if (error) { 971 vput(vp); 972 return (error); 973 } 974 } 975 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 976 if (error != 0) { 977 vput(vp); 978 return (error); 979 } 980 if (vp->v_type != VDIR) { 981 vput(vp); 982 return (ENOTDIR); 983 } 984 VI_LOCK(vp); 985 if ((vp->v_iflag & VI_MOUNT) != 0 || 986 vp->v_mountedhere != NULL) { 987 VI_UNLOCK(vp); 988 vput(vp); 989 return (EBUSY); 990 } 991 vp->v_iflag |= VI_MOUNT; 992 VI_UNLOCK(vp); 993 994 /* 995 * Allocate and initialize the filesystem. 996 */ 997 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 998 VOP_UNLOCK(vp, 0, td); 999 1000 /* XXXMAC: pass to vfs_mount_alloc? */ 1001 mp->mnt_optnew = fsdata; 1002 } 1003 1004 /* 1005 * Set the mount level flags. 1006 */ 1007 MNT_ILOCK(mp); 1008 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 1009 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 1010 MNT_RDONLY)); 1011 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1012 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1013 MNT_IUNLOCK(mp); 1014 /* 1015 * Mount the filesystem. 1016 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1017 * get. No freeing of cn_pnbuf. 1018 */ 1019 error = VFS_MOUNT(mp, td); 1020 1021 /* 1022 * Process the export option only if we are 1023 * updating mount options. 1024 */ 1025 if (!error && (fsflags & MNT_UPDATE)) { 1026 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1027 sizeof(export)) == 0) 1028 error = vfs_export(mp, &export); 1029 } 1030 1031 if (!error) { 1032 if (mp->mnt_opt != NULL) 1033 vfs_freeopts(mp->mnt_opt); 1034 mp->mnt_opt = mp->mnt_optnew; 1035 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 1036 } 1037 /* 1038 * Prevent external consumers of mount options from reading 1039 * mnt_optnew. 1040 */ 1041 mp->mnt_optnew = NULL; 1042 if (mp->mnt_flag & MNT_UPDATE) { 1043 MNT_ILOCK(mp); 1044 if (error) 1045 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1046 (flag & ~MNT_QUOTA); 1047 else 1048 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1049 MNT_FORCE | MNT_SNAPSHOT); 1050 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1051 mp->mnt_kern_flag |= MNTK_ASYNC; 1052 else 1053 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1054 MNT_IUNLOCK(mp); 1055 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1056 if (mp->mnt_syncer == NULL) 1057 error = vfs_allocate_syncvnode(mp); 1058 } else { 1059 if (mp->mnt_syncer != NULL) 1060 vrele(mp->mnt_syncer); 1061 mp->mnt_syncer = NULL; 1062 } 1063 vfs_unbusy(mp, td); 1064 VI_LOCK(vp); 1065 vp->v_iflag &= ~VI_MOUNT; 1066 VI_UNLOCK(vp); 1067 vrele(vp); 1068 return (error); 1069 } 1070 MNT_ILOCK(mp); 1071 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1072 mp->mnt_kern_flag |= MNTK_ASYNC; 1073 else 1074 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1075 MNT_IUNLOCK(mp); 1076 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 1077 /* 1078 * Put the new filesystem on the mount list after root. 1079 */ 1080 cache_purge(vp); 1081 if (!error) { 1082 struct vnode *newdp; 1083 1084 VI_LOCK(vp); 1085 vp->v_iflag &= ~VI_MOUNT; 1086 VI_UNLOCK(vp); 1087 vp->v_mountedhere = mp; 1088 mtx_lock(&mountlist_mtx); 1089 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1090 mtx_unlock(&mountlist_mtx); 1091 vfs_event_signal(NULL, VQ_MOUNT, 0); 1092 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 1093 panic("mount: lost mount"); 1094 mountcheckdirs(vp, newdp); 1095 vput(newdp); 1096 VOP_UNLOCK(vp, 0, td); 1097 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1098 error = vfs_allocate_syncvnode(mp); 1099 vfs_unbusy(mp, td); 1100 if (error) 1101 vrele(vp); 1102 } else { 1103 VI_LOCK(vp); 1104 vp->v_iflag &= ~VI_MOUNT; 1105 VI_UNLOCK(vp); 1106 vfs_unbusy(mp, td); 1107 vfs_mount_destroy(mp); 1108 vput(vp); 1109 } 1110 return (error); 1111 } 1112 1113 /* 1114 * Unmount a filesystem. 1115 * 1116 * Note: unmount takes a path to the vnode mounted on as argument, not 1117 * special file (as before). 1118 */ 1119 #ifndef _SYS_SYSPROTO_H_ 1120 struct unmount_args { 1121 char *path; 1122 int flags; 1123 }; 1124 #endif 1125 /* ARGSUSED */ 1126 int 1127 unmount(td, uap) 1128 struct thread *td; 1129 register struct unmount_args /* { 1130 char *path; 1131 int flags; 1132 } */ *uap; 1133 { 1134 struct mount *mp; 1135 char *pathbuf; 1136 int error, id0, id1; 1137 1138 if (jailed(td->td_ucred) || usermount == 0) { 1139 error = priv_check(td, PRIV_VFS_UNMOUNT); 1140 if (error) 1141 return (error); 1142 } 1143 1144 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1145 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1146 if (error) { 1147 free(pathbuf, M_TEMP); 1148 return (error); 1149 } 1150 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1); 1151 mtx_lock(&Giant); 1152 if (uap->flags & MNT_BYFSID) { 1153 /* Decode the filesystem ID. */ 1154 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1155 mtx_unlock(&Giant); 1156 free(pathbuf, M_TEMP); 1157 return (EINVAL); 1158 } 1159 1160 mtx_lock(&mountlist_mtx); 1161 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1162 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1163 mp->mnt_stat.f_fsid.val[1] == id1) 1164 break; 1165 } 1166 mtx_unlock(&mountlist_mtx); 1167 } else { 1168 mtx_lock(&mountlist_mtx); 1169 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1170 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1171 break; 1172 } 1173 mtx_unlock(&mountlist_mtx); 1174 } 1175 free(pathbuf, M_TEMP); 1176 if (mp == NULL) { 1177 /* 1178 * Previously we returned ENOENT for a nonexistent path and 1179 * EINVAL for a non-mountpoint. We cannot tell these apart 1180 * now, so in the !MNT_BYFSID case return the more likely 1181 * EINVAL for compatibility. 1182 */ 1183 mtx_unlock(&Giant); 1184 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1185 } 1186 1187 /* 1188 * Don't allow unmounting the root filesystem. 1189 */ 1190 if (mp->mnt_flag & MNT_ROOTFS) { 1191 mtx_unlock(&Giant); 1192 return (EINVAL); 1193 } 1194 error = dounmount(mp, uap->flags, td); 1195 mtx_unlock(&Giant); 1196 return (error); 1197 } 1198 1199 /* 1200 * Do the actual filesystem unmount. 1201 */ 1202 int 1203 dounmount(mp, flags, td) 1204 struct mount *mp; 1205 int flags; 1206 struct thread *td; 1207 { 1208 struct vnode *coveredvp, *fsrootvp; 1209 int error; 1210 int async_flag; 1211 int mnt_gen_r; 1212 1213 mtx_assert(&Giant, MA_OWNED); 1214 1215 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1216 mnt_gen_r = mp->mnt_gen; 1217 VI_LOCK(coveredvp); 1218 vholdl(coveredvp); 1219 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY, td); 1220 vdrop(coveredvp); 1221 /* 1222 * Check for mp being unmounted while waiting for the 1223 * covered vnode lock. 1224 */ 1225 if (coveredvp->v_mountedhere != mp || 1226 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1227 VOP_UNLOCK(coveredvp, 0, td); 1228 return (EBUSY); 1229 } 1230 } 1231 /* 1232 * Only privileged root, or (if MNT_USER is set) the user that did the 1233 * original mount is permitted to unmount this filesystem. 1234 */ 1235 error = vfs_suser(mp, td); 1236 if (error) { 1237 if (coveredvp) 1238 VOP_UNLOCK(coveredvp, 0, td); 1239 return (error); 1240 } 1241 1242 MNT_ILOCK(mp); 1243 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1244 MNT_IUNLOCK(mp); 1245 if (coveredvp) 1246 VOP_UNLOCK(coveredvp, 0, td); 1247 return (EBUSY); 1248 } 1249 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1250 /* Allow filesystems to detect that a forced unmount is in progress. */ 1251 if (flags & MNT_FORCE) 1252 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1253 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1254 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1255 if (error) { 1256 MNT_ILOCK(mp); 1257 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ | 1258 MNTK_UNMOUNTF); 1259 if (mp->mnt_kern_flag & MNTK_MWAIT) 1260 wakeup(mp); 1261 MNT_IUNLOCK(mp); 1262 if (coveredvp) 1263 VOP_UNLOCK(coveredvp, 0, td); 1264 return (error); 1265 } 1266 vn_start_write(NULL, &mp, V_WAIT); 1267 1268 if (mp->mnt_flag & MNT_EXPUBLIC) 1269 vfs_setpublicfs(NULL, NULL, NULL); 1270 1271 vfs_msync(mp, MNT_WAIT); 1272 MNT_ILOCK(mp); 1273 async_flag = mp->mnt_flag & MNT_ASYNC; 1274 mp->mnt_flag &= ~MNT_ASYNC; 1275 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1276 MNT_IUNLOCK(mp); 1277 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1278 if (mp->mnt_syncer != NULL) 1279 vrele(mp->mnt_syncer); 1280 /* 1281 * For forced unmounts, move process cdir/rdir refs on the fs root 1282 * vnode to the covered vnode. For non-forced unmounts we want 1283 * such references to cause an EBUSY error. 1284 */ 1285 if ((flags & MNT_FORCE) && 1286 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1287 if (mp->mnt_vnodecovered != NULL) 1288 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1289 if (fsrootvp == rootvnode) { 1290 vrele(rootvnode); 1291 rootvnode = NULL; 1292 } 1293 vput(fsrootvp); 1294 } 1295 if (((mp->mnt_flag & MNT_RDONLY) || 1296 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1297 (flags & MNT_FORCE)) { 1298 error = VFS_UNMOUNT(mp, flags, td); 1299 } 1300 vn_finished_write(mp); 1301 /* 1302 * If we failed to flush the dirty blocks for this mount point, 1303 * undo all the cdir/rdir and rootvnode changes we made above. 1304 * Unless we failed to do so because the device is reporting that 1305 * it doesn't exist anymore. 1306 */ 1307 if (error && error != ENXIO) { 1308 if ((flags & MNT_FORCE) && 1309 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1310 if (mp->mnt_vnodecovered != NULL) 1311 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1312 if (rootvnode == NULL) { 1313 rootvnode = fsrootvp; 1314 vref(rootvnode); 1315 } 1316 vput(fsrootvp); 1317 } 1318 MNT_ILOCK(mp); 1319 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1320 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1321 MNT_IUNLOCK(mp); 1322 (void) vfs_allocate_syncvnode(mp); 1323 MNT_ILOCK(mp); 1324 } 1325 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1326 mp->mnt_flag |= async_flag; 1327 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1328 mp->mnt_kern_flag |= MNTK_ASYNC; 1329 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1330 if (mp->mnt_kern_flag & MNTK_MWAIT) 1331 wakeup(mp); 1332 MNT_IUNLOCK(mp); 1333 if (coveredvp) 1334 VOP_UNLOCK(coveredvp, 0, td); 1335 return (error); 1336 } 1337 mtx_lock(&mountlist_mtx); 1338 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1339 mtx_unlock(&mountlist_mtx); 1340 if (coveredvp != NULL) { 1341 coveredvp->v_mountedhere = NULL; 1342 vput(coveredvp); 1343 } 1344 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1345 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1346 vfs_mount_destroy(mp); 1347 return (0); 1348 } 1349 1350 /* 1351 * --------------------------------------------------------------------- 1352 * Mounting of root filesystem 1353 * 1354 */ 1355 1356 struct root_hold_token { 1357 const char *who; 1358 LIST_ENTRY(root_hold_token) list; 1359 }; 1360 1361 static LIST_HEAD(, root_hold_token) root_holds = 1362 LIST_HEAD_INITIALIZER(&root_holds); 1363 1364 static int root_mount_complete; 1365 1366 /* 1367 * Hold root mount. 1368 */ 1369 struct root_hold_token * 1370 root_mount_hold(const char *identifier) 1371 { 1372 struct root_hold_token *h; 1373 1374 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1375 h->who = identifier; 1376 mtx_lock(&mountlist_mtx); 1377 LIST_INSERT_HEAD(&root_holds, h, list); 1378 mtx_unlock(&mountlist_mtx); 1379 return (h); 1380 } 1381 1382 /* 1383 * Release root mount. 1384 */ 1385 void 1386 root_mount_rel(struct root_hold_token *h) 1387 { 1388 1389 mtx_lock(&mountlist_mtx); 1390 LIST_REMOVE(h, list); 1391 wakeup(&root_holds); 1392 mtx_unlock(&mountlist_mtx); 1393 free(h, M_DEVBUF); 1394 } 1395 1396 /* 1397 * Wait for all subsystems to release root mount. 1398 */ 1399 static void 1400 root_mount_prepare(void) 1401 { 1402 struct root_hold_token *h; 1403 1404 for (;;) { 1405 DROP_GIANT(); 1406 g_waitidle(); 1407 PICKUP_GIANT(); 1408 mtx_lock(&mountlist_mtx); 1409 if (LIST_EMPTY(&root_holds)) { 1410 mtx_unlock(&mountlist_mtx); 1411 break; 1412 } 1413 printf("Root mount waiting for:"); 1414 LIST_FOREACH(h, &root_holds, list) 1415 printf(" %s", h->who); 1416 printf("\n"); 1417 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1418 hz); 1419 } 1420 } 1421 1422 /* 1423 * Root was mounted, share the good news. 1424 */ 1425 static void 1426 root_mount_done(void) 1427 { 1428 1429 /* 1430 * Use a mutex to prevent the wakeup being missed and waiting for 1431 * an extra 1 second sleep. 1432 */ 1433 mtx_lock(&mountlist_mtx); 1434 root_mount_complete = 1; 1435 wakeup(&root_mount_complete); 1436 mtx_unlock(&mountlist_mtx); 1437 } 1438 1439 /* 1440 * Return true if root is already mounted. 1441 */ 1442 int 1443 root_mounted(void) 1444 { 1445 1446 /* No mutex is acquired here because int stores are atomic. */ 1447 return (root_mount_complete); 1448 } 1449 1450 /* 1451 * Wait until root is mounted. 1452 */ 1453 void 1454 root_mount_wait(void) 1455 { 1456 1457 /* 1458 * Panic on an obvious deadlock - the function can't be called from 1459 * a thread which is doing the whole SYSINIT stuff. 1460 */ 1461 KASSERT(curthread->td_proc->p_pid != 0, 1462 ("root_mount_wait: cannot be called from the swapper thread")); 1463 mtx_lock(&mountlist_mtx); 1464 while (!root_mount_complete) { 1465 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1466 hz); 1467 } 1468 mtx_unlock(&mountlist_mtx); 1469 } 1470 1471 static void 1472 set_rootvnode(struct thread *td) 1473 { 1474 struct proc *p; 1475 1476 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1477 panic("Cannot find root vnode"); 1478 1479 p = td->td_proc; 1480 FILEDESC_SLOCK(p->p_fd); 1481 1482 if (p->p_fd->fd_cdir != NULL) 1483 vrele(p->p_fd->fd_cdir); 1484 p->p_fd->fd_cdir = rootvnode; 1485 VREF(rootvnode); 1486 1487 if (p->p_fd->fd_rdir != NULL) 1488 vrele(p->p_fd->fd_rdir); 1489 p->p_fd->fd_rdir = rootvnode; 1490 VREF(rootvnode); 1491 1492 FILEDESC_SUNLOCK(p->p_fd); 1493 1494 VOP_UNLOCK(rootvnode, 0, td); 1495 } 1496 1497 /* 1498 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1499 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1500 */ 1501 1502 static void 1503 devfs_first(void) 1504 { 1505 struct thread *td = curthread; 1506 struct vfsoptlist *opts; 1507 struct vfsconf *vfsp; 1508 struct mount *mp = NULL; 1509 int error; 1510 1511 vfsp = vfs_byname("devfs"); 1512 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1513 if (vfsp == NULL) 1514 return; 1515 1516 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1517 1518 error = VFS_MOUNT(mp, td); 1519 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1520 if (error) 1521 return; 1522 1523 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1524 TAILQ_INIT(opts); 1525 mp->mnt_opt = opts; 1526 1527 mtx_lock(&mountlist_mtx); 1528 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1529 mtx_unlock(&mountlist_mtx); 1530 1531 set_rootvnode(td); 1532 1533 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1534 if (error) 1535 printf("kern_symlink /dev -> / returns %d\n", error); 1536 } 1537 1538 /* 1539 * Surgically move our devfs to be mounted on /dev. 1540 */ 1541 1542 static void 1543 devfs_fixup(struct thread *td) 1544 { 1545 struct nameidata nd; 1546 int error; 1547 struct vnode *vp, *dvp; 1548 struct mount *mp; 1549 1550 /* Remove our devfs mount from the mountlist and purge the cache */ 1551 mtx_lock(&mountlist_mtx); 1552 mp = TAILQ_FIRST(&mountlist); 1553 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1554 mtx_unlock(&mountlist_mtx); 1555 cache_purgevfs(mp); 1556 1557 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1558 VI_LOCK(dvp); 1559 dvp->v_iflag &= ~VI_MOUNT; 1560 VI_UNLOCK(dvp); 1561 dvp->v_mountedhere = NULL; 1562 1563 /* Set up the real rootvnode, and purge the cache */ 1564 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1565 set_rootvnode(td); 1566 cache_purgevfs(rootvnode->v_mount); 1567 1568 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1569 error = namei(&nd); 1570 if (error) { 1571 printf("Lookup of /dev for devfs, error: %d\n", error); 1572 return; 1573 } 1574 NDFREE(&nd, NDF_ONLY_PNBUF); 1575 vp = nd.ni_vp; 1576 if (vp->v_type != VDIR) { 1577 vput(vp); 1578 } 1579 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1580 if (error) { 1581 vput(vp); 1582 } 1583 cache_purge(vp); 1584 mp->mnt_vnodecovered = vp; 1585 vp->v_mountedhere = mp; 1586 mtx_lock(&mountlist_mtx); 1587 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1588 mtx_unlock(&mountlist_mtx); 1589 VOP_UNLOCK(vp, 0, td); 1590 vput(dvp); 1591 vfs_unbusy(mp, td); 1592 1593 /* Unlink the no longer needed /dev/dev -> / symlink */ 1594 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1595 } 1596 1597 /* 1598 * Report errors during filesystem mounting. 1599 */ 1600 void 1601 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1602 { 1603 struct vfsoptlist *moptlist = mp->mnt_optnew; 1604 va_list ap; 1605 int error, len; 1606 char *errmsg; 1607 1608 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1609 if (error || errmsg == NULL || len <= 0) 1610 return; 1611 1612 va_start(ap, fmt); 1613 vsnprintf(errmsg, (size_t)len, fmt, ap); 1614 va_end(ap); 1615 } 1616 1617 /* 1618 * Find and mount the root filesystem 1619 */ 1620 void 1621 vfs_mountroot(void) 1622 { 1623 char *cp; 1624 int error, i, asked = 0; 1625 1626 root_mount_prepare(); 1627 1628 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1629 NULL, NULL, mount_init, mount_fini, 1630 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1631 devfs_first(); 1632 1633 /* 1634 * We are booted with instructions to prompt for the root filesystem. 1635 */ 1636 if (boothowto & RB_ASKNAME) { 1637 if (!vfs_mountroot_ask()) 1638 goto mounted; 1639 asked = 1; 1640 } 1641 1642 /* 1643 * The root filesystem information is compiled in, and we are 1644 * booted with instructions to use it. 1645 */ 1646 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1647 if (!vfs_mountroot_try(ctrootdevname)) 1648 goto mounted; 1649 ctrootdevname = NULL; 1650 } 1651 1652 /* 1653 * We've been given the generic "use CDROM as root" flag. This is 1654 * necessary because one media may be used in many different 1655 * devices, so we need to search for them. 1656 */ 1657 if (boothowto & RB_CDROM) { 1658 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1659 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1660 goto mounted; 1661 } 1662 } 1663 1664 /* 1665 * Try to use the value read by the loader from /etc/fstab, or 1666 * supplied via some other means. This is the preferred 1667 * mechanism. 1668 */ 1669 cp = getenv("vfs.root.mountfrom"); 1670 if (cp != NULL) { 1671 error = vfs_mountroot_try(cp); 1672 freeenv(cp); 1673 if (!error) 1674 goto mounted; 1675 } 1676 1677 /* 1678 * Try values that may have been computed by code during boot 1679 */ 1680 if (!vfs_mountroot_try(rootdevnames[0])) 1681 goto mounted; 1682 if (!vfs_mountroot_try(rootdevnames[1])) 1683 goto mounted; 1684 1685 /* 1686 * If we (still) have a compiled-in default, try it. 1687 */ 1688 if (ctrootdevname != NULL) 1689 if (!vfs_mountroot_try(ctrootdevname)) 1690 goto mounted; 1691 /* 1692 * Everything so far has failed, prompt on the console if we haven't 1693 * already tried that. 1694 */ 1695 if (!asked) 1696 if (!vfs_mountroot_ask()) 1697 goto mounted; 1698 1699 panic("Root mount failed, startup aborted."); 1700 1701 mounted: 1702 root_mount_done(); 1703 } 1704 1705 /* 1706 * Mount (mountfrom) as the root filesystem. 1707 */ 1708 static int 1709 vfs_mountroot_try(const char *mountfrom) 1710 { 1711 struct mount *mp; 1712 char *vfsname, *path; 1713 time_t timebase; 1714 int error; 1715 char patt[32]; 1716 1717 vfsname = NULL; 1718 path = NULL; 1719 mp = NULL; 1720 error = EINVAL; 1721 1722 if (mountfrom == NULL) 1723 return (error); /* don't complain */ 1724 printf("Trying to mount root from %s\n", mountfrom); 1725 1726 /* parse vfs name and path */ 1727 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1728 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1729 vfsname[0] = path[0] = 0; 1730 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1731 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1732 goto out; 1733 1734 if (path[0] == '\0') 1735 strcpy(path, ROOTNAME); 1736 1737 error = kernel_vmount( 1738 MNT_RDONLY | MNT_ROOTFS, 1739 "fstype", vfsname, 1740 "fspath", "/", 1741 "from", path, 1742 NULL); 1743 if (error == 0) { 1744 /* 1745 * We mount devfs prior to mounting the / FS, so the first 1746 * entry will typically be devfs. 1747 */ 1748 mp = TAILQ_FIRST(&mountlist); 1749 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1750 1751 /* 1752 * Iterate over all currently mounted file systems and use 1753 * the time stamp found to check and/or initialize the RTC. 1754 * Typically devfs has no time stamp and the only other FS 1755 * is the actual / FS. 1756 * Call inittodr() only once and pass it the largest of the 1757 * timestamps we encounter. 1758 */ 1759 timebase = 0; 1760 do { 1761 if (mp->mnt_time > timebase) 1762 timebase = mp->mnt_time; 1763 mp = TAILQ_NEXT(mp, mnt_list); 1764 } while (mp != NULL); 1765 inittodr(timebase); 1766 1767 devfs_fixup(curthread); 1768 } 1769 out: 1770 free(path, M_MOUNT); 1771 free(vfsname, M_MOUNT); 1772 return (error); 1773 } 1774 1775 /* 1776 * --------------------------------------------------------------------- 1777 * Interactive root filesystem selection code. 1778 */ 1779 1780 static int 1781 vfs_mountroot_ask(void) 1782 { 1783 char name[128]; 1784 1785 for(;;) { 1786 printf("\nManual root filesystem specification:\n"); 1787 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1788 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1789 printf(" eg. ufs:da0s1a\n"); 1790 #else 1791 printf(" eg. ufs:/dev/da0a\n"); 1792 #endif 1793 printf(" ? List valid disk boot devices\n"); 1794 printf(" <empty line> Abort manual input\n"); 1795 printf("\nmountroot> "); 1796 gets(name, sizeof(name), 1); 1797 if (name[0] == '\0') 1798 return (1); 1799 if (name[0] == '?') { 1800 printf("\nList of GEOM managed disk devices:\n "); 1801 g_dev_print(); 1802 continue; 1803 } 1804 if (!vfs_mountroot_try(name)) 1805 return (0); 1806 } 1807 } 1808 1809 /* 1810 * --------------------------------------------------------------------- 1811 * Functions for querying mount options/arguments from filesystems. 1812 */ 1813 1814 /* 1815 * Check that no unknown options are given 1816 */ 1817 int 1818 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1819 { 1820 struct vfsopt *opt; 1821 char errmsg[255]; 1822 const char **t, *p, *q; 1823 int ret = 0; 1824 1825 TAILQ_FOREACH(opt, opts, link) { 1826 p = opt->name; 1827 q = NULL; 1828 if (p[0] == 'n' && p[1] == 'o') 1829 q = p + 2; 1830 for(t = global_opts; *t != NULL; t++) { 1831 if (strcmp(*t, p) == 0) 1832 break; 1833 if (q != NULL) { 1834 if (strcmp(*t, q) == 0) 1835 break; 1836 } 1837 } 1838 if (*t != NULL) 1839 continue; 1840 for(t = legal; *t != NULL; t++) { 1841 if (strcmp(*t, p) == 0) 1842 break; 1843 if (q != NULL) { 1844 if (strcmp(*t, q) == 0) 1845 break; 1846 } 1847 } 1848 if (*t != NULL) 1849 continue; 1850 snprintf(errmsg, sizeof(errmsg), 1851 "mount option <%s> is unknown", p); 1852 printf("%s\n", errmsg); 1853 ret = EINVAL; 1854 } 1855 if (ret != 0) { 1856 TAILQ_FOREACH(opt, opts, link) { 1857 if (strcmp(opt->name, "errmsg") == 0) { 1858 strncpy((char *)opt->value, errmsg, opt->len); 1859 } 1860 } 1861 } 1862 return (ret); 1863 } 1864 1865 /* 1866 * Get a mount option by its name. 1867 * 1868 * Return 0 if the option was found, ENOENT otherwise. 1869 * If len is non-NULL it will be filled with the length 1870 * of the option. If buf is non-NULL, it will be filled 1871 * with the address of the option. 1872 */ 1873 int 1874 vfs_getopt(opts, name, buf, len) 1875 struct vfsoptlist *opts; 1876 const char *name; 1877 void **buf; 1878 int *len; 1879 { 1880 struct vfsopt *opt; 1881 1882 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1883 1884 TAILQ_FOREACH(opt, opts, link) { 1885 if (strcmp(name, opt->name) == 0) { 1886 if (len != NULL) 1887 *len = opt->len; 1888 if (buf != NULL) 1889 *buf = opt->value; 1890 return (0); 1891 } 1892 } 1893 return (ENOENT); 1894 } 1895 1896 static int 1897 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1898 { 1899 struct vfsopt *opt; 1900 int i; 1901 1902 if (opts == NULL) 1903 return (-1); 1904 1905 i = 0; 1906 TAILQ_FOREACH(opt, opts, link) { 1907 if (strcmp(name, opt->name) == 0) 1908 return (i); 1909 ++i; 1910 } 1911 return (-1); 1912 } 1913 1914 char * 1915 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1916 { 1917 struct vfsopt *opt; 1918 1919 *error = 0; 1920 TAILQ_FOREACH(opt, opts, link) { 1921 if (strcmp(name, opt->name) != 0) 1922 continue; 1923 if (((char *)opt->value)[opt->len - 1] != '\0') { 1924 *error = EINVAL; 1925 return (NULL); 1926 } 1927 return (opt->value); 1928 } 1929 *error = ENOENT; 1930 return (NULL); 1931 } 1932 1933 int 1934 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1935 { 1936 struct vfsopt *opt; 1937 1938 TAILQ_FOREACH(opt, opts, link) { 1939 if (strcmp(name, opt->name) == 0) { 1940 if (w != NULL) 1941 *w |= val; 1942 return (1); 1943 } 1944 } 1945 if (w != NULL) 1946 *w &= ~val; 1947 return (0); 1948 } 1949 1950 int 1951 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1952 { 1953 va_list ap; 1954 struct vfsopt *opt; 1955 int ret; 1956 1957 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1958 1959 TAILQ_FOREACH(opt, opts, link) { 1960 if (strcmp(name, opt->name) != 0) 1961 continue; 1962 if (opt->len == 0 || opt->value == NULL) 1963 return (0); 1964 if (((char *)opt->value)[opt->len - 1] != '\0') 1965 return (0); 1966 va_start(ap, fmt); 1967 ret = vsscanf(opt->value, fmt, ap); 1968 va_end(ap); 1969 return (ret); 1970 } 1971 return (0); 1972 } 1973 1974 /* 1975 * Find and copy a mount option. 1976 * 1977 * The size of the buffer has to be specified 1978 * in len, if it is not the same length as the 1979 * mount option, EINVAL is returned. 1980 * Returns ENOENT if the option is not found. 1981 */ 1982 int 1983 vfs_copyopt(opts, name, dest, len) 1984 struct vfsoptlist *opts; 1985 const char *name; 1986 void *dest; 1987 int len; 1988 { 1989 struct vfsopt *opt; 1990 1991 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1992 1993 TAILQ_FOREACH(opt, opts, link) { 1994 if (strcmp(name, opt->name) == 0) { 1995 if (len != opt->len) 1996 return (EINVAL); 1997 bcopy(opt->value, dest, opt->len); 1998 return (0); 1999 } 2000 } 2001 return (ENOENT); 2002 } 2003 2004 /* 2005 * This is a helper function for filesystems to traverse their 2006 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 2007 */ 2008 2009 struct vnode * 2010 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 2011 { 2012 struct vnode *vp; 2013 2014 mtx_assert(MNT_MTX(mp), MA_OWNED); 2015 2016 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2017 if ((*mvp)->v_yield++ == 500) { 2018 MNT_IUNLOCK(mp); 2019 (*mvp)->v_yield = 0; 2020 uio_yield(); 2021 MNT_ILOCK(mp); 2022 } 2023 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 2024 while (vp != NULL && vp->v_type == VMARKER) 2025 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2026 2027 /* Check if we are done */ 2028 if (vp == NULL) { 2029 __mnt_vnode_markerfree(mvp, mp); 2030 return (NULL); 2031 } 2032 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2033 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2034 return (vp); 2035 } 2036 2037 struct vnode * 2038 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2039 { 2040 struct vnode *vp; 2041 2042 mtx_assert(MNT_MTX(mp), MA_OWNED); 2043 2044 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2045 while (vp != NULL && vp->v_type == VMARKER) 2046 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2047 2048 /* Check if we are done */ 2049 if (vp == NULL) { 2050 *mvp = NULL; 2051 return (NULL); 2052 } 2053 mp->mnt_holdcnt++; 2054 MNT_IUNLOCK(mp); 2055 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2056 M_VNODE_MARKER, 2057 M_WAITOK | M_ZERO); 2058 MNT_ILOCK(mp); 2059 (*mvp)->v_type = VMARKER; 2060 2061 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2062 while (vp != NULL && vp->v_type == VMARKER) 2063 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2064 2065 /* Check if we are done */ 2066 if (vp == NULL) { 2067 MNT_IUNLOCK(mp); 2068 free(*mvp, M_VNODE_MARKER); 2069 MNT_ILOCK(mp); 2070 *mvp = NULL; 2071 mp->mnt_holdcnt--; 2072 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2073 wakeup(&mp->mnt_holdcnt); 2074 return (NULL); 2075 } 2076 mp->mnt_markercnt++; 2077 (*mvp)->v_mount = mp; 2078 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2079 return (vp); 2080 } 2081 2082 2083 void 2084 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2085 { 2086 2087 if (*mvp == NULL) 2088 return; 2089 2090 mtx_assert(MNT_MTX(mp), MA_OWNED); 2091 2092 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2093 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2094 MNT_IUNLOCK(mp); 2095 free(*mvp, M_VNODE_MARKER); 2096 MNT_ILOCK(mp); 2097 *mvp = NULL; 2098 2099 mp->mnt_markercnt--; 2100 mp->mnt_holdcnt--; 2101 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2102 wakeup(&mp->mnt_holdcnt); 2103 } 2104 2105 2106 int 2107 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 2108 { 2109 int error; 2110 2111 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 2112 if (sbp != &mp->mnt_stat) 2113 *sbp = mp->mnt_stat; 2114 return (error); 2115 } 2116 2117 void 2118 vfs_mountedfrom(struct mount *mp, const char *from) 2119 { 2120 2121 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2122 strlcpy(mp->mnt_stat.f_mntfromname, from, 2123 sizeof mp->mnt_stat.f_mntfromname); 2124 } 2125 2126 /* 2127 * --------------------------------------------------------------------- 2128 * This is the api for building mount args and mounting filesystems from 2129 * inside the kernel. 2130 * 2131 * The API works by accumulation of individual args. First error is 2132 * latched. 2133 * 2134 * XXX: should be documented in new manpage kernel_mount(9) 2135 */ 2136 2137 /* A memory allocation which must be freed when we are done */ 2138 struct mntaarg { 2139 SLIST_ENTRY(mntaarg) next; 2140 }; 2141 2142 /* The header for the mount arguments */ 2143 struct mntarg { 2144 struct iovec *v; 2145 int len; 2146 int error; 2147 SLIST_HEAD(, mntaarg) list; 2148 }; 2149 2150 /* 2151 * Add a boolean argument. 2152 * 2153 * flag is the boolean value. 2154 * name must start with "no". 2155 */ 2156 struct mntarg * 2157 mount_argb(struct mntarg *ma, int flag, const char *name) 2158 { 2159 2160 KASSERT(name[0] == 'n' && name[1] == 'o', 2161 ("mount_argb(...,%s): name must start with 'no'", name)); 2162 2163 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2164 } 2165 2166 /* 2167 * Add an argument printf style 2168 */ 2169 struct mntarg * 2170 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2171 { 2172 va_list ap; 2173 struct mntaarg *maa; 2174 struct sbuf *sb; 2175 int len; 2176 2177 if (ma == NULL) { 2178 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2179 SLIST_INIT(&ma->list); 2180 } 2181 if (ma->error) 2182 return (ma); 2183 2184 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2185 M_MOUNT, M_WAITOK); 2186 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2187 ma->v[ma->len].iov_len = strlen(name) + 1; 2188 ma->len++; 2189 2190 sb = sbuf_new_auto(); 2191 va_start(ap, fmt); 2192 sbuf_vprintf(sb, fmt, ap); 2193 va_end(ap); 2194 sbuf_finish(sb); 2195 len = sbuf_len(sb) + 1; 2196 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2197 SLIST_INSERT_HEAD(&ma->list, maa, next); 2198 bcopy(sbuf_data(sb), maa + 1, len); 2199 sbuf_delete(sb); 2200 2201 ma->v[ma->len].iov_base = maa + 1; 2202 ma->v[ma->len].iov_len = len; 2203 ma->len++; 2204 2205 return (ma); 2206 } 2207 2208 /* 2209 * Add an argument which is a userland string. 2210 */ 2211 struct mntarg * 2212 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2213 { 2214 struct mntaarg *maa; 2215 char *tbuf; 2216 2217 if (val == NULL) 2218 return (ma); 2219 if (ma == NULL) { 2220 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2221 SLIST_INIT(&ma->list); 2222 } 2223 if (ma->error) 2224 return (ma); 2225 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2226 SLIST_INSERT_HEAD(&ma->list, maa, next); 2227 tbuf = (void *)(maa + 1); 2228 ma->error = copyinstr(val, tbuf, len, NULL); 2229 return (mount_arg(ma, name, tbuf, -1)); 2230 } 2231 2232 /* 2233 * Plain argument. 2234 * 2235 * If length is -1, use printf. 2236 */ 2237 struct mntarg * 2238 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2239 { 2240 2241 if (ma == NULL) { 2242 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2243 SLIST_INIT(&ma->list); 2244 } 2245 if (ma->error) 2246 return (ma); 2247 2248 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2249 M_MOUNT, M_WAITOK); 2250 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2251 ma->v[ma->len].iov_len = strlen(name) + 1; 2252 ma->len++; 2253 2254 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2255 if (len < 0) 2256 ma->v[ma->len].iov_len = strlen(val) + 1; 2257 else 2258 ma->v[ma->len].iov_len = len; 2259 ma->len++; 2260 return (ma); 2261 } 2262 2263 /* 2264 * Free a mntarg structure 2265 */ 2266 static void 2267 free_mntarg(struct mntarg *ma) 2268 { 2269 struct mntaarg *maa; 2270 2271 while (!SLIST_EMPTY(&ma->list)) { 2272 maa = SLIST_FIRST(&ma->list); 2273 SLIST_REMOVE_HEAD(&ma->list, next); 2274 free(maa, M_MOUNT); 2275 } 2276 free(ma->v, M_MOUNT); 2277 free(ma, M_MOUNT); 2278 } 2279 2280 /* 2281 * Mount a filesystem 2282 */ 2283 int 2284 kernel_mount(struct mntarg *ma, int flags) 2285 { 2286 struct uio auio; 2287 int error; 2288 2289 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2290 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2291 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2292 2293 auio.uio_iov = ma->v; 2294 auio.uio_iovcnt = ma->len; 2295 auio.uio_segflg = UIO_SYSSPACE; 2296 2297 error = ma->error; 2298 if (!error) 2299 error = vfs_donmount(curthread, flags, &auio); 2300 free_mntarg(ma); 2301 return (error); 2302 } 2303 2304 /* 2305 * A printflike function to mount a filesystem. 2306 */ 2307 int 2308 kernel_vmount(int flags, ...) 2309 { 2310 struct mntarg *ma = NULL; 2311 va_list ap; 2312 const char *cp; 2313 const void *vp; 2314 int error; 2315 2316 va_start(ap, flags); 2317 for (;;) { 2318 cp = va_arg(ap, const char *); 2319 if (cp == NULL) 2320 break; 2321 vp = va_arg(ap, const void *); 2322 ma = mount_arg(ma, cp, vp, -1); 2323 } 2324 va_end(ap); 2325 2326 error = kernel_mount(ma, flags); 2327 return (error); 2328 }
Cache object: 2586c47ee8d6a65956f7f30a6f473d10
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]