Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_mount.c
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1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1999-2004 Poul-Henning Kamp 5 * Copyright (c) 1999 Michael Smith 6 * Copyright (c) 1989, 1993 7 * The Regents of the University of California. All rights reserved. 8 * (c) UNIX System Laboratories, Inc. 9 * All or some portions of this file are derived from material licensed 10 * to the University of California by American Telephone and Telegraph 11 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 12 * the permission of UNIX System Laboratories, Inc. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include <sys/param.h> 43 #include <sys/conf.h> 44 #include <sys/smp.h> 45 #include <sys/devctl.h> 46 #include <sys/eventhandler.h> 47 #include <sys/fcntl.h> 48 #include <sys/jail.h> 49 #include <sys/kernel.h> 50 #include <sys/ktr.h> 51 #include <sys/libkern.h> 52 #include <sys/malloc.h> 53 #include <sys/mount.h> 54 #include <sys/mutex.h> 55 #include <sys/namei.h> 56 #include <sys/priv.h> 57 #include <sys/proc.h> 58 #include <sys/filedesc.h> 59 #include <sys/reboot.h> 60 #include <sys/sbuf.h> 61 #include <sys/syscallsubr.h> 62 #include <sys/sysproto.h> 63 #include <sys/sx.h> 64 #include <sys/sysctl.h> 65 #include <sys/sysent.h> 66 #include <sys/systm.h> 67 #include <sys/vnode.h> 68 #include <vm/uma.h> 69 70 #include <geom/geom.h> 71 72 #include <machine/stdarg.h> 73 74 #include <security/audit/audit.h> 75 #include <security/mac/mac_framework.h> 76 77 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 78 79 static int vfs_domount(struct thread *td, const char *fstype, char *fspath, 80 uint64_t fsflags, struct vfsoptlist **optlist); 81 static void free_mntarg(struct mntarg *ma); 82 83 static int usermount = 0; 84 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 85 "Unprivileged users may mount and unmount file systems"); 86 87 static bool default_autoro = false; 88 SYSCTL_BOOL(_vfs, OID_AUTO, default_autoro, CTLFLAG_RW, &default_autoro, 0, 89 "Retry failed r/w mount as r/o if no explicit ro/rw option is specified"); 90 91 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 92 MALLOC_DEFINE(M_STATFS, "statfs", "statfs structure"); 93 static uma_zone_t mount_zone; 94 95 /* List of mounted filesystems. */ 96 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 97 98 /* For any iteration/modification of mountlist */ 99 struct mtx_padalign __exclusive_cache_line mountlist_mtx; 100 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 101 102 EVENTHANDLER_LIST_DEFINE(vfs_mounted); 103 EVENTHANDLER_LIST_DEFINE(vfs_unmounted); 104 105 static void mount_devctl_event(const char *type, struct mount *mp, bool donew); 106 107 /* 108 * Global opts, taken by all filesystems 109 */ 110 static const char *global_opts[] = { 111 "errmsg", 112 "fstype", 113 "fspath", 114 "ro", 115 "rw", 116 "nosuid", 117 "noexec", 118 NULL 119 }; 120 121 static int 122 mount_init(void *mem, int size, int flags) 123 { 124 struct mount *mp; 125 126 mp = (struct mount *)mem; 127 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 128 mtx_init(&mp->mnt_listmtx, "struct mount vlist mtx", NULL, MTX_DEF); 129 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 130 mp->mnt_pcpu = uma_zalloc_pcpu(pcpu_zone_16, M_WAITOK | M_ZERO); 131 mp->mnt_ref = 0; 132 mp->mnt_vfs_ops = 1; 133 mp->mnt_rootvnode = NULL; 134 return (0); 135 } 136 137 static void 138 mount_fini(void *mem, int size) 139 { 140 struct mount *mp; 141 142 mp = (struct mount *)mem; 143 uma_zfree_pcpu(pcpu_zone_16, mp->mnt_pcpu); 144 lockdestroy(&mp->mnt_explock); 145 mtx_destroy(&mp->mnt_listmtx); 146 mtx_destroy(&mp->mnt_mtx); 147 } 148 149 static void 150 vfs_mount_init(void *dummy __unused) 151 { 152 153 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), NULL, 154 NULL, mount_init, mount_fini, UMA_ALIGN_CACHE, UMA_ZONE_NOFREE); 155 } 156 SYSINIT(vfs_mount, SI_SUB_VFS, SI_ORDER_ANY, vfs_mount_init, NULL); 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 free(opt, M_MOUNT); 173 } 174 175 /* Release all resources related to the mount options. */ 176 void 177 vfs_freeopts(struct vfsoptlist *opts) 178 { 179 struct vfsopt *opt; 180 181 while (!TAILQ_EMPTY(opts)) { 182 opt = TAILQ_FIRST(opts); 183 vfs_freeopt(opts, opt); 184 } 185 free(opts, M_MOUNT); 186 } 187 188 void 189 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 190 { 191 struct vfsopt *opt, *temp; 192 193 if (opts == NULL) 194 return; 195 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 196 if (strcmp(opt->name, name) == 0) 197 vfs_freeopt(opts, opt); 198 } 199 } 200 201 static int 202 vfs_isopt_ro(const char *opt) 203 { 204 205 if (strcmp(opt, "ro") == 0 || strcmp(opt, "rdonly") == 0 || 206 strcmp(opt, "norw") == 0) 207 return (1); 208 return (0); 209 } 210 211 static int 212 vfs_isopt_rw(const char *opt) 213 { 214 215 if (strcmp(opt, "rw") == 0 || strcmp(opt, "noro") == 0) 216 return (1); 217 return (0); 218 } 219 220 /* 221 * Check if options are equal (with or without the "no" prefix). 222 */ 223 static int 224 vfs_equalopts(const char *opt1, const char *opt2) 225 { 226 char *p; 227 228 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 229 if (strcmp(opt1, opt2) == 0) 230 return (1); 231 /* "noopt" vs. "opt" */ 232 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 233 return (1); 234 /* "opt" vs. "noopt" */ 235 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 236 return (1); 237 while ((p = strchr(opt1, '.')) != NULL && 238 !strncmp(opt1, opt2, ++p - opt1)) { 239 opt2 += p - opt1; 240 opt1 = p; 241 /* "foo.noopt" vs. "foo.opt" */ 242 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 243 return (1); 244 /* "foo.opt" vs. "foo.noopt" */ 245 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 246 return (1); 247 } 248 /* "ro" / "rdonly" / "norw" / "rw" / "noro" */ 249 if ((vfs_isopt_ro(opt1) || vfs_isopt_rw(opt1)) && 250 (vfs_isopt_ro(opt2) || vfs_isopt_rw(opt2))) 251 return (1); 252 return (0); 253 } 254 255 /* 256 * If a mount option is specified several times, 257 * (with or without the "no" prefix) only keep 258 * the last occurrence of it. 259 */ 260 static void 261 vfs_sanitizeopts(struct vfsoptlist *opts) 262 { 263 struct vfsopt *opt, *opt2, *tmp; 264 265 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 266 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 267 while (opt2 != NULL) { 268 if (vfs_equalopts(opt->name, opt2->name)) { 269 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 270 vfs_freeopt(opts, opt2); 271 opt2 = tmp; 272 } else { 273 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 274 } 275 } 276 } 277 } 278 279 /* 280 * Build a linked list of mount options from a struct uio. 281 */ 282 int 283 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 284 { 285 struct vfsoptlist *opts; 286 struct vfsopt *opt; 287 size_t memused, namelen, optlen; 288 unsigned int i, iovcnt; 289 int error; 290 291 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 292 TAILQ_INIT(opts); 293 memused = 0; 294 iovcnt = auio->uio_iovcnt; 295 for (i = 0; i < iovcnt; i += 2) { 296 namelen = auio->uio_iov[i].iov_len; 297 optlen = auio->uio_iov[i + 1].iov_len; 298 memused += sizeof(struct vfsopt) + optlen + namelen; 299 /* 300 * Avoid consuming too much memory, and attempts to overflow 301 * memused. 302 */ 303 if (memused > VFS_MOUNTARG_SIZE_MAX || 304 optlen > VFS_MOUNTARG_SIZE_MAX || 305 namelen > VFS_MOUNTARG_SIZE_MAX) { 306 error = EINVAL; 307 goto bad; 308 } 309 310 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 311 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 312 opt->value = NULL; 313 opt->len = 0; 314 opt->pos = i / 2; 315 opt->seen = 0; 316 317 /* 318 * Do this early, so jumps to "bad" will free the current 319 * option. 320 */ 321 TAILQ_INSERT_TAIL(opts, opt, link); 322 323 if (auio->uio_segflg == UIO_SYSSPACE) { 324 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 325 } else { 326 error = copyin(auio->uio_iov[i].iov_base, opt->name, 327 namelen); 328 if (error) 329 goto bad; 330 } 331 /* Ensure names are null-terminated strings. */ 332 if (namelen == 0 || opt->name[namelen - 1] != '\0') { 333 error = EINVAL; 334 goto bad; 335 } 336 if (optlen != 0) { 337 opt->len = optlen; 338 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 339 if (auio->uio_segflg == UIO_SYSSPACE) { 340 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 341 optlen); 342 } else { 343 error = copyin(auio->uio_iov[i + 1].iov_base, 344 opt->value, optlen); 345 if (error) 346 goto bad; 347 } 348 } 349 } 350 vfs_sanitizeopts(opts); 351 *options = opts; 352 return (0); 353 bad: 354 vfs_freeopts(opts); 355 return (error); 356 } 357 358 /* 359 * Merge the old mount options with the new ones passed 360 * in the MNT_UPDATE case. 361 * 362 * XXX: This function will keep a "nofoo" option in the new 363 * options. E.g, if the option's canonical name is "foo", 364 * "nofoo" ends up in the mount point's active options. 365 */ 366 static void 367 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *oldopts) 368 { 369 struct vfsopt *opt, *new; 370 371 TAILQ_FOREACH(opt, oldopts, link) { 372 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 373 new->name = strdup(opt->name, M_MOUNT); 374 if (opt->len != 0) { 375 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 376 bcopy(opt->value, new->value, opt->len); 377 } else 378 new->value = NULL; 379 new->len = opt->len; 380 new->seen = opt->seen; 381 TAILQ_INSERT_HEAD(toopts, new, link); 382 } 383 vfs_sanitizeopts(toopts); 384 } 385 386 /* 387 * Mount a filesystem. 388 */ 389 #ifndef _SYS_SYSPROTO_H_ 390 struct nmount_args { 391 struct iovec *iovp; 392 unsigned int iovcnt; 393 int flags; 394 }; 395 #endif 396 int 397 sys_nmount(struct thread *td, struct nmount_args *uap) 398 { 399 struct uio *auio; 400 int error; 401 u_int iovcnt; 402 uint64_t flags; 403 404 /* 405 * Mount flags are now 64-bits. On 32-bit archtectures only 406 * 32-bits are passed in, but from here on everything handles 407 * 64-bit flags correctly. 408 */ 409 flags = uap->flags; 410 411 AUDIT_ARG_FFLAGS(flags); 412 CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__, 413 uap->iovp, uap->iovcnt, flags); 414 415 /* 416 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 417 * userspace to set this flag, but we must filter it out if we want 418 * MNT_UPDATE on the root file system to work. 419 * MNT_ROOTFS should only be set by the kernel when mounting its 420 * root file system. 421 */ 422 flags &= ~MNT_ROOTFS; 423 424 iovcnt = uap->iovcnt; 425 /* 426 * Check that we have an even number of iovec's 427 * and that we have at least two options. 428 */ 429 if ((iovcnt & 1) || (iovcnt < 4)) { 430 CTR2(KTR_VFS, "%s: failed for invalid iovcnt %d", __func__, 431 uap->iovcnt); 432 return (EINVAL); 433 } 434 435 error = copyinuio(uap->iovp, iovcnt, &auio); 436 if (error) { 437 CTR2(KTR_VFS, "%s: failed for invalid uio op with %d errno", 438 __func__, error); 439 return (error); 440 } 441 error = vfs_donmount(td, flags, auio); 442 443 free(auio, M_IOV); 444 return (error); 445 } 446 447 /* 448 * --------------------------------------------------------------------- 449 * Various utility functions 450 */ 451 452 /* 453 * Get a reference on a mount point from a vnode. 454 * 455 * The vnode is allowed to be passed unlocked and race against dooming. Note in 456 * such case there are no guarantees the referenced mount point will still be 457 * associated with it after the function returns. 458 */ 459 struct mount * 460 vfs_ref_from_vp(struct vnode *vp) 461 { 462 struct mount *mp; 463 struct mount_pcpu *mpcpu; 464 465 mp = atomic_load_ptr(&vp->v_mount); 466 if (__predict_false(mp == NULL)) { 467 return (mp); 468 } 469 if (vfs_op_thread_enter(mp, mpcpu)) { 470 if (__predict_true(mp == vp->v_mount)) { 471 vfs_mp_count_add_pcpu(mpcpu, ref, 1); 472 vfs_op_thread_exit(mp, mpcpu); 473 } else { 474 vfs_op_thread_exit(mp, mpcpu); 475 mp = NULL; 476 } 477 } else { 478 MNT_ILOCK(mp); 479 if (mp == vp->v_mount) { 480 MNT_REF(mp); 481 MNT_IUNLOCK(mp); 482 } else { 483 MNT_IUNLOCK(mp); 484 mp = NULL; 485 } 486 } 487 return (mp); 488 } 489 490 void 491 vfs_ref(struct mount *mp) 492 { 493 struct mount_pcpu *mpcpu; 494 495 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 496 if (vfs_op_thread_enter(mp, mpcpu)) { 497 vfs_mp_count_add_pcpu(mpcpu, ref, 1); 498 vfs_op_thread_exit(mp, mpcpu); 499 return; 500 } 501 502 MNT_ILOCK(mp); 503 MNT_REF(mp); 504 MNT_IUNLOCK(mp); 505 } 506 507 void 508 vfs_rel(struct mount *mp) 509 { 510 struct mount_pcpu *mpcpu; 511 512 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 513 if (vfs_op_thread_enter(mp, mpcpu)) { 514 vfs_mp_count_sub_pcpu(mpcpu, ref, 1); 515 vfs_op_thread_exit(mp, mpcpu); 516 return; 517 } 518 519 MNT_ILOCK(mp); 520 MNT_REL(mp); 521 MNT_IUNLOCK(mp); 522 } 523 524 /* 525 * Allocate and initialize the mount point struct. 526 */ 527 struct mount * 528 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, const char *fspath, 529 struct ucred *cred) 530 { 531 struct mount *mp; 532 533 mp = uma_zalloc(mount_zone, M_WAITOK); 534 bzero(&mp->mnt_startzero, 535 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 536 mp->mnt_kern_flag = 0; 537 mp->mnt_flag = 0; 538 mp->mnt_rootvnode = NULL; 539 mp->mnt_vnodecovered = NULL; 540 mp->mnt_op = NULL; 541 mp->mnt_vfc = NULL; 542 TAILQ_INIT(&mp->mnt_nvnodelist); 543 mp->mnt_nvnodelistsize = 0; 544 TAILQ_INIT(&mp->mnt_lazyvnodelist); 545 mp->mnt_lazyvnodelistsize = 0; 546 if (mp->mnt_ref != 0 || mp->mnt_lockref != 0 || 547 mp->mnt_writeopcount != 0) 548 panic("%s: non-zero counters on new mp %p\n", __func__, mp); 549 if (mp->mnt_vfs_ops != 1) 550 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 551 mp->mnt_vfs_ops); 552 (void) vfs_busy(mp, MBF_NOWAIT); 553 atomic_add_acq_int(&vfsp->vfc_refcount, 1); 554 mp->mnt_op = vfsp->vfc_vfsops; 555 mp->mnt_vfc = vfsp; 556 mp->mnt_stat.f_type = vfsp->vfc_typenum; 557 mp->mnt_gen++; 558 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 559 mp->mnt_vnodecovered = vp; 560 mp->mnt_cred = crdup(cred); 561 mp->mnt_stat.f_owner = cred->cr_uid; 562 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 563 mp->mnt_iosize_max = DFLTPHYS; 564 #ifdef MAC 565 mac_mount_init(mp); 566 mac_mount_create(cred, mp); 567 #endif 568 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 569 TAILQ_INIT(&mp->mnt_uppers); 570 return (mp); 571 } 572 573 /* 574 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 575 */ 576 void 577 vfs_mount_destroy(struct mount *mp) 578 { 579 580 if (mp->mnt_vfs_ops == 0) 581 panic("%s: entered with zero vfs_ops\n", __func__); 582 583 vfs_assert_mount_counters(mp); 584 585 MNT_ILOCK(mp); 586 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 587 if (mp->mnt_kern_flag & MNTK_MWAIT) { 588 mp->mnt_kern_flag &= ~MNTK_MWAIT; 589 wakeup(mp); 590 } 591 while (mp->mnt_ref) 592 msleep(mp, MNT_MTX(mp), PVFS, "mntref", 0); 593 KASSERT(mp->mnt_ref == 0, 594 ("%s: invalid refcount in the drain path @ %s:%d", __func__, 595 __FILE__, __LINE__)); 596 if (mp->mnt_writeopcount != 0) 597 panic("vfs_mount_destroy: nonzero writeopcount"); 598 if (mp->mnt_secondary_writes != 0) 599 panic("vfs_mount_destroy: nonzero secondary_writes"); 600 atomic_subtract_rel_int(&mp->mnt_vfc->vfc_refcount, 1); 601 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 602 struct vnode *vp; 603 604 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 605 vn_printf(vp, "dangling vnode "); 606 panic("unmount: dangling vnode"); 607 } 608 KASSERT(TAILQ_EMPTY(&mp->mnt_uppers), ("mnt_uppers")); 609 if (mp->mnt_nvnodelistsize != 0) 610 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 611 if (mp->mnt_lazyvnodelistsize != 0) 612 panic("vfs_mount_destroy: nonzero lazyvnodelistsize"); 613 if (mp->mnt_lockref != 0) 614 panic("vfs_mount_destroy: nonzero lock refcount"); 615 MNT_IUNLOCK(mp); 616 617 if (mp->mnt_vfs_ops != 1) 618 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 619 mp->mnt_vfs_ops); 620 621 if (mp->mnt_rootvnode != NULL) 622 panic("%s: mount point still has a root vnode %p\n", __func__, 623 mp->mnt_rootvnode); 624 625 if (mp->mnt_vnodecovered != NULL) 626 vrele(mp->mnt_vnodecovered); 627 #ifdef MAC 628 mac_mount_destroy(mp); 629 #endif 630 if (mp->mnt_opt != NULL) 631 vfs_freeopts(mp->mnt_opt); 632 crfree(mp->mnt_cred); 633 uma_zfree(mount_zone, mp); 634 } 635 636 static bool 637 vfs_should_downgrade_to_ro_mount(uint64_t fsflags, int error) 638 { 639 /* This is an upgrade of an exisiting mount. */ 640 if ((fsflags & MNT_UPDATE) != 0) 641 return (false); 642 /* This is already an R/O mount. */ 643 if ((fsflags & MNT_RDONLY) != 0) 644 return (false); 645 646 switch (error) { 647 case ENODEV: /* generic, geom, ... */ 648 case EACCES: /* cam/scsi, ... */ 649 case EROFS: /* md, mmcsd, ... */ 650 /* 651 * These errors can be returned by the storage layer to signal 652 * that the media is read-only. No harm in the R/O mount 653 * attempt if the error was returned for some other reason. 654 */ 655 return (true); 656 default: 657 return (false); 658 } 659 } 660 661 int 662 vfs_donmount(struct thread *td, uint64_t fsflags, struct uio *fsoptions) 663 { 664 struct vfsoptlist *optlist; 665 struct vfsopt *opt, *tmp_opt; 666 char *fstype, *fspath, *errmsg; 667 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 668 bool autoro; 669 670 errmsg = fspath = NULL; 671 errmsg_len = fspathlen = 0; 672 errmsg_pos = -1; 673 autoro = default_autoro; 674 675 error = vfs_buildopts(fsoptions, &optlist); 676 if (error) 677 return (error); 678 679 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 680 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 681 682 /* 683 * We need these two options before the others, 684 * and they are mandatory for any filesystem. 685 * Ensure they are NUL terminated as well. 686 */ 687 fstypelen = 0; 688 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 689 if (error || fstypelen <= 0 || fstype[fstypelen - 1] != '\0') { 690 error = EINVAL; 691 if (errmsg != NULL) 692 strncpy(errmsg, "Invalid fstype", errmsg_len); 693 goto bail; 694 } 695 fspathlen = 0; 696 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 697 if (error || fspathlen <= 0 || fspath[fspathlen - 1] != '\0') { 698 error = EINVAL; 699 if (errmsg != NULL) 700 strncpy(errmsg, "Invalid fspath", errmsg_len); 701 goto bail; 702 } 703 704 /* 705 * We need to see if we have the "update" option 706 * before we call vfs_domount(), since vfs_domount() has special 707 * logic based on MNT_UPDATE. This is very important 708 * when we want to update the root filesystem. 709 */ 710 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 711 int do_freeopt = 0; 712 713 if (strcmp(opt->name, "update") == 0) { 714 fsflags |= MNT_UPDATE; 715 do_freeopt = 1; 716 } 717 else if (strcmp(opt->name, "async") == 0) 718 fsflags |= MNT_ASYNC; 719 else if (strcmp(opt->name, "force") == 0) { 720 fsflags |= MNT_FORCE; 721 do_freeopt = 1; 722 } 723 else if (strcmp(opt->name, "reload") == 0) { 724 fsflags |= MNT_RELOAD; 725 do_freeopt = 1; 726 } 727 else if (strcmp(opt->name, "multilabel") == 0) 728 fsflags |= MNT_MULTILABEL; 729 else if (strcmp(opt->name, "noasync") == 0) 730 fsflags &= ~MNT_ASYNC; 731 else if (strcmp(opt->name, "noatime") == 0) 732 fsflags |= MNT_NOATIME; 733 else if (strcmp(opt->name, "atime") == 0) { 734 free(opt->name, M_MOUNT); 735 opt->name = strdup("nonoatime", M_MOUNT); 736 } 737 else if (strcmp(opt->name, "noclusterr") == 0) 738 fsflags |= MNT_NOCLUSTERR; 739 else if (strcmp(opt->name, "clusterr") == 0) { 740 free(opt->name, M_MOUNT); 741 opt->name = strdup("nonoclusterr", M_MOUNT); 742 } 743 else if (strcmp(opt->name, "noclusterw") == 0) 744 fsflags |= MNT_NOCLUSTERW; 745 else if (strcmp(opt->name, "clusterw") == 0) { 746 free(opt->name, M_MOUNT); 747 opt->name = strdup("nonoclusterw", M_MOUNT); 748 } 749 else if (strcmp(opt->name, "noexec") == 0) 750 fsflags |= MNT_NOEXEC; 751 else if (strcmp(opt->name, "exec") == 0) { 752 free(opt->name, M_MOUNT); 753 opt->name = strdup("nonoexec", M_MOUNT); 754 } 755 else if (strcmp(opt->name, "nosuid") == 0) 756 fsflags |= MNT_NOSUID; 757 else if (strcmp(opt->name, "suid") == 0) { 758 free(opt->name, M_MOUNT); 759 opt->name = strdup("nonosuid", M_MOUNT); 760 } 761 else if (strcmp(opt->name, "nosymfollow") == 0) 762 fsflags |= MNT_NOSYMFOLLOW; 763 else if (strcmp(opt->name, "symfollow") == 0) { 764 free(opt->name, M_MOUNT); 765 opt->name = strdup("nonosymfollow", M_MOUNT); 766 } 767 else if (strcmp(opt->name, "noro") == 0) { 768 fsflags &= ~MNT_RDONLY; 769 autoro = false; 770 } 771 else if (strcmp(opt->name, "rw") == 0) { 772 fsflags &= ~MNT_RDONLY; 773 autoro = false; 774 } 775 else if (strcmp(opt->name, "ro") == 0) { 776 fsflags |= MNT_RDONLY; 777 autoro = false; 778 } 779 else if (strcmp(opt->name, "rdonly") == 0) { 780 free(opt->name, M_MOUNT); 781 opt->name = strdup("ro", M_MOUNT); 782 fsflags |= MNT_RDONLY; 783 autoro = false; 784 } 785 else if (strcmp(opt->name, "autoro") == 0) { 786 do_freeopt = 1; 787 autoro = true; 788 } 789 else if (strcmp(opt->name, "suiddir") == 0) 790 fsflags |= MNT_SUIDDIR; 791 else if (strcmp(opt->name, "sync") == 0) 792 fsflags |= MNT_SYNCHRONOUS; 793 else if (strcmp(opt->name, "union") == 0) 794 fsflags |= MNT_UNION; 795 else if (strcmp(opt->name, "automounted") == 0) { 796 fsflags |= MNT_AUTOMOUNTED; 797 do_freeopt = 1; 798 } else if (strcmp(opt->name, "nocover") == 0) { 799 fsflags |= MNT_NOCOVER; 800 do_freeopt = 1; 801 } else if (strcmp(opt->name, "cover") == 0) { 802 fsflags &= ~MNT_NOCOVER; 803 do_freeopt = 1; 804 } else if (strcmp(opt->name, "emptydir") == 0) { 805 fsflags |= MNT_EMPTYDIR; 806 do_freeopt = 1; 807 } else if (strcmp(opt->name, "noemptydir") == 0) { 808 fsflags &= ~MNT_EMPTYDIR; 809 do_freeopt = 1; 810 } 811 if (do_freeopt) 812 vfs_freeopt(optlist, opt); 813 } 814 815 /* 816 * Be ultra-paranoid about making sure the type and fspath 817 * variables will fit in our mp buffers, including the 818 * terminating NUL. 819 */ 820 if (fstypelen > MFSNAMELEN || fspathlen > MNAMELEN) { 821 error = ENAMETOOLONG; 822 goto bail; 823 } 824 825 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 826 827 /* 828 * See if we can mount in the read-only mode if the error code suggests 829 * that it could be possible and the mount options allow for that. 830 * Never try it if "[no]{ro|rw}" has been explicitly requested and not 831 * overridden by "autoro". 832 */ 833 if (autoro && vfs_should_downgrade_to_ro_mount(fsflags, error)) { 834 printf("%s: R/W mount failed, possibly R/O media," 835 " trying R/O mount\n", __func__); 836 fsflags |= MNT_RDONLY; 837 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 838 } 839 bail: 840 /* copyout the errmsg */ 841 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 842 && errmsg_len > 0 && errmsg != NULL) { 843 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 844 bcopy(errmsg, 845 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 846 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 847 } else { 848 copyout(errmsg, 849 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 850 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 851 } 852 } 853 854 if (optlist != NULL) 855 vfs_freeopts(optlist); 856 return (error); 857 } 858 859 /* 860 * Old mount API. 861 */ 862 #ifndef _SYS_SYSPROTO_H_ 863 struct mount_args { 864 char *type; 865 char *path; 866 int flags; 867 caddr_t data; 868 }; 869 #endif 870 /* ARGSUSED */ 871 int 872 sys_mount(struct thread *td, struct mount_args *uap) 873 { 874 char *fstype; 875 struct vfsconf *vfsp = NULL; 876 struct mntarg *ma = NULL; 877 uint64_t flags; 878 int error; 879 880 /* 881 * Mount flags are now 64-bits. On 32-bit architectures only 882 * 32-bits are passed in, but from here on everything handles 883 * 64-bit flags correctly. 884 */ 885 flags = uap->flags; 886 887 AUDIT_ARG_FFLAGS(flags); 888 889 /* 890 * Filter out MNT_ROOTFS. We do not want clients of mount() in 891 * userspace to set this flag, but we must filter it out if we want 892 * MNT_UPDATE on the root file system to work. 893 * MNT_ROOTFS should only be set by the kernel when mounting its 894 * root file system. 895 */ 896 flags &= ~MNT_ROOTFS; 897 898 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 899 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 900 if (error) { 901 free(fstype, M_TEMP); 902 return (error); 903 } 904 905 AUDIT_ARG_TEXT(fstype); 906 vfsp = vfs_byname_kld(fstype, td, &error); 907 free(fstype, M_TEMP); 908 if (vfsp == NULL) 909 return (ENOENT); 910 if (((vfsp->vfc_flags & VFCF_SBDRY) != 0 && 911 vfsp->vfc_vfsops_sd->vfs_cmount == NULL) || 912 ((vfsp->vfc_flags & VFCF_SBDRY) == 0 && 913 vfsp->vfc_vfsops->vfs_cmount == NULL)) 914 return (EOPNOTSUPP); 915 916 ma = mount_argsu(ma, "fstype", uap->type, MFSNAMELEN); 917 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 918 ma = mount_argb(ma, flags & MNT_RDONLY, "noro"); 919 ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid"); 920 ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec"); 921 922 if ((vfsp->vfc_flags & VFCF_SBDRY) != 0) 923 return (vfsp->vfc_vfsops_sd->vfs_cmount(ma, uap->data, flags)); 924 return (vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags)); 925 } 926 927 /* 928 * vfs_domount_first(): first file system mount (not update) 929 */ 930 static int 931 vfs_domount_first( 932 struct thread *td, /* Calling thread. */ 933 struct vfsconf *vfsp, /* File system type. */ 934 char *fspath, /* Mount path. */ 935 struct vnode *vp, /* Vnode to be covered. */ 936 uint64_t fsflags, /* Flags common to all filesystems. */ 937 struct vfsoptlist **optlist /* Options local to the filesystem. */ 938 ) 939 { 940 struct vattr va; 941 struct mount *mp; 942 struct vnode *newdp, *rootvp; 943 int error, error1; 944 bool unmounted; 945 946 ASSERT_VOP_ELOCKED(vp, __func__); 947 KASSERT((fsflags & MNT_UPDATE) == 0, ("MNT_UPDATE shouldn't be here")); 948 949 /* 950 * If the jail of the calling thread lacks permission for this type of 951 * file system, or is trying to cover its own root, deny immediately. 952 */ 953 if (jailed(td->td_ucred) && (!prison_allow(td->td_ucred, 954 vfsp->vfc_prison_flag) || vp == td->td_ucred->cr_prison->pr_root)) { 955 vput(vp); 956 return (EPERM); 957 } 958 959 /* 960 * If the user is not root, ensure that they own the directory 961 * onto which we are attempting to mount. 962 */ 963 error = VOP_GETATTR(vp, &va, td->td_ucred); 964 if (error == 0 && va.va_uid != td->td_ucred->cr_uid) 965 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN); 966 if (error == 0) 967 error = vinvalbuf(vp, V_SAVE, 0, 0); 968 if (error == 0 && vp->v_type != VDIR) 969 error = ENOTDIR; 970 if (error == 0 && (fsflags & MNT_EMPTYDIR) != 0) 971 error = vfs_emptydir(vp); 972 if (error == 0) { 973 VI_LOCK(vp); 974 if ((vp->v_iflag & VI_MOUNT) == 0 && vp->v_mountedhere == NULL) 975 vp->v_iflag |= VI_MOUNT; 976 else 977 error = EBUSY; 978 VI_UNLOCK(vp); 979 } 980 if (error != 0) { 981 vput(vp); 982 return (error); 983 } 984 vn_seqc_write_begin(vp); 985 VOP_UNLOCK(vp); 986 987 /* Allocate and initialize the filesystem. */ 988 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 989 /* XXXMAC: pass to vfs_mount_alloc? */ 990 mp->mnt_optnew = *optlist; 991 /* Set the mount level flags. */ 992 mp->mnt_flag = (fsflags & (MNT_UPDATEMASK | MNT_ROOTFS | MNT_RDONLY)); 993 994 /* 995 * Mount the filesystem. 996 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 997 * get. No freeing of cn_pnbuf. 998 */ 999 error1 = 0; 1000 unmounted = true; 1001 if ((error = VFS_MOUNT(mp)) != 0 || 1002 (error1 = VFS_STATFS(mp, &mp->mnt_stat)) != 0 || 1003 (error1 = VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) != 0) { 1004 rootvp = NULL; 1005 if (error1 != 0) { 1006 MPASS(error == 0); 1007 rootvp = vfs_cache_root_clear(mp); 1008 if (rootvp != NULL) { 1009 vhold(rootvp); 1010 vrele(rootvp); 1011 } 1012 (void)vn_start_write(NULL, &mp, V_WAIT); 1013 MNT_ILOCK(mp); 1014 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_UNMOUNTF; 1015 MNT_IUNLOCK(mp); 1016 VFS_PURGE(mp); 1017 error = VFS_UNMOUNT(mp, 0); 1018 vn_finished_write(mp); 1019 if (error != 0) { 1020 printf( 1021 "failed post-mount (%d): rollback unmount returned %d\n", 1022 error1, error); 1023 unmounted = false; 1024 } 1025 error = error1; 1026 } 1027 vfs_unbusy(mp); 1028 mp->mnt_vnodecovered = NULL; 1029 if (unmounted) { 1030 /* XXXKIB wait for mnt_lockref drain? */ 1031 vfs_mount_destroy(mp); 1032 } 1033 VI_LOCK(vp); 1034 vp->v_iflag &= ~VI_MOUNT; 1035 VI_UNLOCK(vp); 1036 if (rootvp != NULL) { 1037 vn_seqc_write_end(rootvp); 1038 vdrop(rootvp); 1039 } 1040 vn_seqc_write_end(vp); 1041 vrele(vp); 1042 return (error); 1043 } 1044 vn_seqc_write_begin(newdp); 1045 VOP_UNLOCK(newdp); 1046 1047 if (mp->mnt_opt != NULL) 1048 vfs_freeopts(mp->mnt_opt); 1049 mp->mnt_opt = mp->mnt_optnew; 1050 *optlist = NULL; 1051 1052 /* 1053 * Prevent external consumers of mount options from reading mnt_optnew. 1054 */ 1055 mp->mnt_optnew = NULL; 1056 1057 MNT_ILOCK(mp); 1058 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1059 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1060 mp->mnt_kern_flag |= MNTK_ASYNC; 1061 else 1062 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1063 MNT_IUNLOCK(mp); 1064 1065 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1066 cache_purge(vp); 1067 VI_LOCK(vp); 1068 vp->v_iflag &= ~VI_MOUNT; 1069 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT); 1070 vp->v_mountedhere = mp; 1071 VI_UNLOCK(vp); 1072 /* Place the new filesystem at the end of the mount list. */ 1073 mtx_lock(&mountlist_mtx); 1074 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1075 mtx_unlock(&mountlist_mtx); 1076 vfs_event_signal(NULL, VQ_MOUNT, 0); 1077 vn_lock(newdp, LK_EXCLUSIVE | LK_RETRY); 1078 VOP_UNLOCK(vp); 1079 EVENTHANDLER_DIRECT_INVOKE(vfs_mounted, mp, newdp, td); 1080 VOP_UNLOCK(newdp); 1081 mount_devctl_event("MOUNT", mp, false); 1082 mountcheckdirs(vp, newdp); 1083 vn_seqc_write_end(vp); 1084 vn_seqc_write_end(newdp); 1085 vrele(newdp); 1086 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1087 vfs_allocate_syncvnode(mp); 1088 vfs_op_exit(mp); 1089 vfs_unbusy(mp); 1090 return (0); 1091 } 1092 1093 /* 1094 * vfs_domount_update(): update of mounted file system 1095 */ 1096 static int 1097 vfs_domount_update( 1098 struct thread *td, /* Calling thread. */ 1099 struct vnode *vp, /* Mount point vnode. */ 1100 uint64_t fsflags, /* Flags common to all filesystems. */ 1101 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1102 ) 1103 { 1104 struct export_args export; 1105 struct o2export_args o2export; 1106 struct vnode *rootvp; 1107 void *bufp; 1108 struct mount *mp; 1109 int error, export_error, i, len; 1110 uint64_t flag; 1111 gid_t *grps; 1112 1113 ASSERT_VOP_ELOCKED(vp, __func__); 1114 KASSERT((fsflags & MNT_UPDATE) != 0, ("MNT_UPDATE should be here")); 1115 mp = vp->v_mount; 1116 1117 if ((vp->v_vflag & VV_ROOT) == 0) { 1118 if (vfs_copyopt(*optlist, "export", &export, sizeof(export)) 1119 == 0) 1120 error = EXDEV; 1121 else 1122 error = EINVAL; 1123 vput(vp); 1124 return (error); 1125 } 1126 1127 /* 1128 * We only allow the filesystem to be reloaded if it 1129 * is currently mounted read-only. 1130 */ 1131 flag = mp->mnt_flag; 1132 if ((fsflags & MNT_RELOAD) != 0 && (flag & MNT_RDONLY) == 0) { 1133 vput(vp); 1134 return (EOPNOTSUPP); /* Needs translation */ 1135 } 1136 /* 1137 * Only privileged root, or (if MNT_USER is set) the user that 1138 * did the original mount is permitted to update it. 1139 */ 1140 error = vfs_suser(mp, td); 1141 if (error != 0) { 1142 vput(vp); 1143 return (error); 1144 } 1145 if (vfs_busy(mp, MBF_NOWAIT)) { 1146 vput(vp); 1147 return (EBUSY); 1148 } 1149 VI_LOCK(vp); 1150 if ((vp->v_iflag & VI_MOUNT) != 0 || vp->v_mountedhere != NULL) { 1151 VI_UNLOCK(vp); 1152 vfs_unbusy(mp); 1153 vput(vp); 1154 return (EBUSY); 1155 } 1156 vp->v_iflag |= VI_MOUNT; 1157 VI_UNLOCK(vp); 1158 VOP_UNLOCK(vp); 1159 1160 vfs_op_enter(mp); 1161 vn_seqc_write_begin(vp); 1162 1163 rootvp = NULL; 1164 MNT_ILOCK(mp); 1165 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) { 1166 MNT_IUNLOCK(mp); 1167 error = EBUSY; 1168 goto end; 1169 } 1170 mp->mnt_flag &= ~MNT_UPDATEMASK; 1171 mp->mnt_flag |= fsflags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | 1172 MNT_SNAPSHOT | MNT_ROOTFS | MNT_UPDATEMASK | MNT_RDONLY); 1173 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1174 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1175 rootvp = vfs_cache_root_clear(mp); 1176 MNT_IUNLOCK(mp); 1177 mp->mnt_optnew = *optlist; 1178 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 1179 1180 /* 1181 * Mount the filesystem. 1182 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1183 * get. No freeing of cn_pnbuf. 1184 */ 1185 error = VFS_MOUNT(mp); 1186 1187 export_error = 0; 1188 /* Process the export option. */ 1189 if (error == 0 && vfs_getopt(mp->mnt_optnew, "export", &bufp, 1190 &len) == 0) { 1191 /* Assume that there is only 1 ABI for each length. */ 1192 switch (len) { 1193 case (sizeof(struct oexport_args)): 1194 bzero(&o2export, sizeof(o2export)); 1195 /* FALLTHROUGH */ 1196 case (sizeof(o2export)): 1197 bcopy(bufp, &o2export, len); 1198 export.ex_flags = (uint64_t)o2export.ex_flags; 1199 export.ex_root = o2export.ex_root; 1200 export.ex_uid = o2export.ex_anon.cr_uid; 1201 export.ex_groups = NULL; 1202 export.ex_ngroups = o2export.ex_anon.cr_ngroups; 1203 if (export.ex_ngroups > 0) { 1204 if (export.ex_ngroups <= XU_NGROUPS) { 1205 export.ex_groups = malloc( 1206 export.ex_ngroups * sizeof(gid_t), 1207 M_TEMP, M_WAITOK); 1208 for (i = 0; i < export.ex_ngroups; i++) 1209 export.ex_groups[i] = 1210 o2export.ex_anon.cr_groups[i]; 1211 } else 1212 export_error = EINVAL; 1213 } else if (export.ex_ngroups < 0) 1214 export_error = EINVAL; 1215 export.ex_addr = o2export.ex_addr; 1216 export.ex_addrlen = o2export.ex_addrlen; 1217 export.ex_mask = o2export.ex_mask; 1218 export.ex_masklen = o2export.ex_masklen; 1219 export.ex_indexfile = o2export.ex_indexfile; 1220 export.ex_numsecflavors = o2export.ex_numsecflavors; 1221 if (export.ex_numsecflavors < MAXSECFLAVORS) { 1222 for (i = 0; i < export.ex_numsecflavors; i++) 1223 export.ex_secflavors[i] = 1224 o2export.ex_secflavors[i]; 1225 } else 1226 export_error = EINVAL; 1227 if (export_error == 0) 1228 export_error = vfs_export(mp, &export); 1229 free(export.ex_groups, M_TEMP); 1230 break; 1231 case (sizeof(export)): 1232 bcopy(bufp, &export, len); 1233 grps = NULL; 1234 if (export.ex_ngroups > 0) { 1235 if (export.ex_ngroups <= NGROUPS_MAX) { 1236 grps = malloc(export.ex_ngroups * 1237 sizeof(gid_t), M_TEMP, M_WAITOK); 1238 export_error = copyin(export.ex_groups, 1239 grps, export.ex_ngroups * 1240 sizeof(gid_t)); 1241 if (export_error == 0) 1242 export.ex_groups = grps; 1243 } else 1244 export_error = EINVAL; 1245 } else if (export.ex_ngroups == 0) 1246 export.ex_groups = NULL; 1247 else 1248 export_error = EINVAL; 1249 if (export_error == 0) 1250 export_error = vfs_export(mp, &export); 1251 free(grps, M_TEMP); 1252 break; 1253 default: 1254 export_error = EINVAL; 1255 break; 1256 } 1257 } 1258 1259 MNT_ILOCK(mp); 1260 if (error == 0) { 1261 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 1262 MNT_SNAPSHOT); 1263 } else { 1264 /* 1265 * If we fail, restore old mount flags. MNT_QUOTA is special, 1266 * because it is not part of MNT_UPDATEMASK, but it could have 1267 * changed in the meantime if quotactl(2) was called. 1268 * All in all we want current value of MNT_QUOTA, not the old 1269 * one. 1270 */ 1271 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 1272 } 1273 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1274 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1275 mp->mnt_kern_flag |= MNTK_ASYNC; 1276 else 1277 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1278 MNT_IUNLOCK(mp); 1279 1280 if (error != 0) 1281 goto end; 1282 1283 mount_devctl_event("REMOUNT", mp, true); 1284 if (mp->mnt_opt != NULL) 1285 vfs_freeopts(mp->mnt_opt); 1286 mp->mnt_opt = mp->mnt_optnew; 1287 *optlist = NULL; 1288 (void)VFS_STATFS(mp, &mp->mnt_stat); 1289 /* 1290 * Prevent external consumers of mount options from reading 1291 * mnt_optnew. 1292 */ 1293 mp->mnt_optnew = NULL; 1294 1295 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1296 vfs_allocate_syncvnode(mp); 1297 else 1298 vfs_deallocate_syncvnode(mp); 1299 end: 1300 vfs_op_exit(mp); 1301 if (rootvp != NULL) { 1302 vn_seqc_write_end(rootvp); 1303 vrele(rootvp); 1304 } 1305 vn_seqc_write_end(vp); 1306 vfs_unbusy(mp); 1307 VI_LOCK(vp); 1308 vp->v_iflag &= ~VI_MOUNT; 1309 VI_UNLOCK(vp); 1310 vrele(vp); 1311 return (error != 0 ? error : export_error); 1312 } 1313 1314 /* 1315 * vfs_domount(): actually attempt a filesystem mount. 1316 */ 1317 static int 1318 vfs_domount( 1319 struct thread *td, /* Calling thread. */ 1320 const char *fstype, /* Filesystem type. */ 1321 char *fspath, /* Mount path. */ 1322 uint64_t fsflags, /* Flags common to all filesystems. */ 1323 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1324 ) 1325 { 1326 struct vfsconf *vfsp; 1327 struct nameidata nd; 1328 struct vnode *vp; 1329 char *pathbuf; 1330 int error; 1331 1332 /* 1333 * Be ultra-paranoid about making sure the type and fspath 1334 * variables will fit in our mp buffers, including the 1335 * terminating NUL. 1336 */ 1337 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1338 return (ENAMETOOLONG); 1339 1340 if (jailed(td->td_ucred) || usermount == 0) { 1341 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1342 return (error); 1343 } 1344 1345 /* 1346 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1347 */ 1348 if (fsflags & MNT_EXPORTED) { 1349 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1350 if (error) 1351 return (error); 1352 } 1353 if (fsflags & MNT_SUIDDIR) { 1354 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1355 if (error) 1356 return (error); 1357 } 1358 /* 1359 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1360 */ 1361 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1362 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1363 fsflags |= MNT_NOSUID | MNT_USER; 1364 } 1365 1366 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1367 vfsp = NULL; 1368 if ((fsflags & MNT_UPDATE) == 0) { 1369 /* Don't try to load KLDs if we're mounting the root. */ 1370 if (fsflags & MNT_ROOTFS) 1371 vfsp = vfs_byname(fstype); 1372 else 1373 vfsp = vfs_byname_kld(fstype, td, &error); 1374 if (vfsp == NULL) 1375 return (ENODEV); 1376 } 1377 1378 /* 1379 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1380 */ 1381 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1382 UIO_SYSSPACE, fspath, td); 1383 error = namei(&nd); 1384 if (error != 0) 1385 return (error); 1386 NDFREE(&nd, NDF_ONLY_PNBUF); 1387 vp = nd.ni_vp; 1388 if ((fsflags & MNT_UPDATE) == 0) { 1389 if ((vp->v_vflag & VV_ROOT) != 0 && 1390 (fsflags & MNT_NOCOVER) != 0) { 1391 vput(vp); 1392 return (EBUSY); 1393 } 1394 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1395 strcpy(pathbuf, fspath); 1396 error = vn_path_to_global_path(td, vp, pathbuf, MNAMELEN); 1397 if (error == 0) { 1398 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1399 fsflags, optlist); 1400 } 1401 free(pathbuf, M_TEMP); 1402 } else 1403 error = vfs_domount_update(td, vp, fsflags, optlist); 1404 1405 return (error); 1406 } 1407 1408 /* 1409 * Unmount a filesystem. 1410 * 1411 * Note: unmount takes a path to the vnode mounted on as argument, not 1412 * special file (as before). 1413 */ 1414 #ifndef _SYS_SYSPROTO_H_ 1415 struct unmount_args { 1416 char *path; 1417 int flags; 1418 }; 1419 #endif 1420 /* ARGSUSED */ 1421 int 1422 sys_unmount(struct thread *td, struct unmount_args *uap) 1423 { 1424 1425 return (kern_unmount(td, uap->path, uap->flags)); 1426 } 1427 1428 int 1429 kern_unmount(struct thread *td, const char *path, int flags) 1430 { 1431 struct nameidata nd; 1432 struct mount *mp; 1433 char *pathbuf; 1434 int error, id0, id1; 1435 1436 AUDIT_ARG_VALUE(flags); 1437 if (jailed(td->td_ucred) || usermount == 0) { 1438 error = priv_check(td, PRIV_VFS_UNMOUNT); 1439 if (error) 1440 return (error); 1441 } 1442 1443 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1444 error = copyinstr(path, pathbuf, MNAMELEN, NULL); 1445 if (error) { 1446 free(pathbuf, M_TEMP); 1447 return (error); 1448 } 1449 if (flags & MNT_BYFSID) { 1450 AUDIT_ARG_TEXT(pathbuf); 1451 /* Decode the filesystem ID. */ 1452 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1453 free(pathbuf, M_TEMP); 1454 return (EINVAL); 1455 } 1456 1457 mtx_lock(&mountlist_mtx); 1458 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1459 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1460 mp->mnt_stat.f_fsid.val[1] == id1) { 1461 vfs_ref(mp); 1462 break; 1463 } 1464 } 1465 mtx_unlock(&mountlist_mtx); 1466 } else { 1467 /* 1468 * Try to find global path for path argument. 1469 */ 1470 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1471 UIO_SYSSPACE, pathbuf, td); 1472 if (namei(&nd) == 0) { 1473 NDFREE(&nd, NDF_ONLY_PNBUF); 1474 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1475 MNAMELEN); 1476 if (error == 0) 1477 vput(nd.ni_vp); 1478 } 1479 mtx_lock(&mountlist_mtx); 1480 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1481 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1482 vfs_ref(mp); 1483 break; 1484 } 1485 } 1486 mtx_unlock(&mountlist_mtx); 1487 } 1488 free(pathbuf, M_TEMP); 1489 if (mp == NULL) { 1490 /* 1491 * Previously we returned ENOENT for a nonexistent path and 1492 * EINVAL for a non-mountpoint. We cannot tell these apart 1493 * now, so in the !MNT_BYFSID case return the more likely 1494 * EINVAL for compatibility. 1495 */ 1496 return ((flags & MNT_BYFSID) ? ENOENT : EINVAL); 1497 } 1498 1499 /* 1500 * Don't allow unmounting the root filesystem. 1501 */ 1502 if (mp->mnt_flag & MNT_ROOTFS) { 1503 vfs_rel(mp); 1504 return (EINVAL); 1505 } 1506 error = dounmount(mp, flags, td); 1507 return (error); 1508 } 1509 1510 /* 1511 * Return error if any of the vnodes, ignoring the root vnode 1512 * and the syncer vnode, have non-zero usecount. 1513 * 1514 * This function is purely advisory - it can return false positives 1515 * and negatives. 1516 */ 1517 static int 1518 vfs_check_usecounts(struct mount *mp) 1519 { 1520 struct vnode *vp, *mvp; 1521 1522 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 1523 if ((vp->v_vflag & VV_ROOT) == 0 && vp->v_type != VNON && 1524 vp->v_usecount != 0) { 1525 VI_UNLOCK(vp); 1526 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 1527 return (EBUSY); 1528 } 1529 VI_UNLOCK(vp); 1530 } 1531 1532 return (0); 1533 } 1534 1535 static void 1536 dounmount_cleanup(struct mount *mp, struct vnode *coveredvp, int mntkflags) 1537 { 1538 1539 mtx_assert(MNT_MTX(mp), MA_OWNED); 1540 mp->mnt_kern_flag &= ~mntkflags; 1541 if ((mp->mnt_kern_flag & MNTK_MWAIT) != 0) { 1542 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1543 wakeup(mp); 1544 } 1545 vfs_op_exit_locked(mp); 1546 MNT_IUNLOCK(mp); 1547 if (coveredvp != NULL) { 1548 VOP_UNLOCK(coveredvp); 1549 vdrop(coveredvp); 1550 } 1551 vn_finished_write(mp); 1552 } 1553 1554 /* 1555 * There are various reference counters associated with the mount point. 1556 * Normally it is permitted to modify them without taking the mnt ilock, 1557 * but this behavior can be temporarily disabled if stable value is needed 1558 * or callers are expected to block (e.g. to not allow new users during 1559 * forced unmount). 1560 */ 1561 void 1562 vfs_op_enter(struct mount *mp) 1563 { 1564 struct mount_pcpu *mpcpu; 1565 int cpu; 1566 1567 MNT_ILOCK(mp); 1568 mp->mnt_vfs_ops++; 1569 if (mp->mnt_vfs_ops > 1) { 1570 MNT_IUNLOCK(mp); 1571 return; 1572 } 1573 vfs_op_barrier_wait(mp); 1574 CPU_FOREACH(cpu) { 1575 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1576 1577 mp->mnt_ref += mpcpu->mntp_ref; 1578 mpcpu->mntp_ref = 0; 1579 1580 mp->mnt_lockref += mpcpu->mntp_lockref; 1581 mpcpu->mntp_lockref = 0; 1582 1583 mp->mnt_writeopcount += mpcpu->mntp_writeopcount; 1584 mpcpu->mntp_writeopcount = 0; 1585 } 1586 if (mp->mnt_ref <= 0 || mp->mnt_lockref < 0 || mp->mnt_writeopcount < 0) 1587 panic("%s: invalid count(s) on mp %p: ref %d lockref %d writeopcount %d\n", 1588 __func__, mp, mp->mnt_ref, mp->mnt_lockref, mp->mnt_writeopcount); 1589 MNT_IUNLOCK(mp); 1590 vfs_assert_mount_counters(mp); 1591 } 1592 1593 void 1594 vfs_op_exit_locked(struct mount *mp) 1595 { 1596 1597 mtx_assert(MNT_MTX(mp), MA_OWNED); 1598 1599 if (mp->mnt_vfs_ops <= 0) 1600 panic("%s: invalid vfs_ops count %d for mp %p\n", 1601 __func__, mp->mnt_vfs_ops, mp); 1602 mp->mnt_vfs_ops--; 1603 } 1604 1605 void 1606 vfs_op_exit(struct mount *mp) 1607 { 1608 1609 MNT_ILOCK(mp); 1610 vfs_op_exit_locked(mp); 1611 MNT_IUNLOCK(mp); 1612 } 1613 1614 struct vfs_op_barrier_ipi { 1615 struct mount *mp; 1616 struct smp_rendezvous_cpus_retry_arg srcra; 1617 }; 1618 1619 static void 1620 vfs_op_action_func(void *arg) 1621 { 1622 struct vfs_op_barrier_ipi *vfsopipi; 1623 struct mount *mp; 1624 1625 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1626 mp = vfsopipi->mp; 1627 1628 if (!vfs_op_thread_entered(mp)) 1629 smp_rendezvous_cpus_done(arg); 1630 } 1631 1632 static void 1633 vfs_op_wait_func(void *arg, int cpu) 1634 { 1635 struct vfs_op_barrier_ipi *vfsopipi; 1636 struct mount *mp; 1637 struct mount_pcpu *mpcpu; 1638 1639 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1640 mp = vfsopipi->mp; 1641 1642 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1643 while (atomic_load_int(&mpcpu->mntp_thread_in_ops)) 1644 cpu_spinwait(); 1645 } 1646 1647 void 1648 vfs_op_barrier_wait(struct mount *mp) 1649 { 1650 struct vfs_op_barrier_ipi vfsopipi; 1651 1652 vfsopipi.mp = mp; 1653 1654 smp_rendezvous_cpus_retry(all_cpus, 1655 smp_no_rendezvous_barrier, 1656 vfs_op_action_func, 1657 smp_no_rendezvous_barrier, 1658 vfs_op_wait_func, 1659 &vfsopipi.srcra); 1660 } 1661 1662 #ifdef DIAGNOSTIC 1663 void 1664 vfs_assert_mount_counters(struct mount *mp) 1665 { 1666 struct mount_pcpu *mpcpu; 1667 int cpu; 1668 1669 if (mp->mnt_vfs_ops == 0) 1670 return; 1671 1672 CPU_FOREACH(cpu) { 1673 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1674 if (mpcpu->mntp_ref != 0 || 1675 mpcpu->mntp_lockref != 0 || 1676 mpcpu->mntp_writeopcount != 0) 1677 vfs_dump_mount_counters(mp); 1678 } 1679 } 1680 1681 void 1682 vfs_dump_mount_counters(struct mount *mp) 1683 { 1684 struct mount_pcpu *mpcpu; 1685 int ref, lockref, writeopcount; 1686 int cpu; 1687 1688 printf("%s: mp %p vfs_ops %d\n", __func__, mp, mp->mnt_vfs_ops); 1689 1690 printf(" ref : "); 1691 ref = mp->mnt_ref; 1692 CPU_FOREACH(cpu) { 1693 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1694 printf("%d ", mpcpu->mntp_ref); 1695 ref += mpcpu->mntp_ref; 1696 } 1697 printf("\n"); 1698 printf(" lockref : "); 1699 lockref = mp->mnt_lockref; 1700 CPU_FOREACH(cpu) { 1701 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1702 printf("%d ", mpcpu->mntp_lockref); 1703 lockref += mpcpu->mntp_lockref; 1704 } 1705 printf("\n"); 1706 printf("writeopcount: "); 1707 writeopcount = mp->mnt_writeopcount; 1708 CPU_FOREACH(cpu) { 1709 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1710 printf("%d ", mpcpu->mntp_writeopcount); 1711 writeopcount += mpcpu->mntp_writeopcount; 1712 } 1713 printf("\n"); 1714 1715 printf("counter struct total\n"); 1716 printf("ref %-5d %-5d\n", mp->mnt_ref, ref); 1717 printf("lockref %-5d %-5d\n", mp->mnt_lockref, lockref); 1718 printf("writeopcount %-5d %-5d\n", mp->mnt_writeopcount, writeopcount); 1719 1720 panic("invalid counts on struct mount"); 1721 } 1722 #endif 1723 1724 int 1725 vfs_mount_fetch_counter(struct mount *mp, enum mount_counter which) 1726 { 1727 struct mount_pcpu *mpcpu; 1728 int cpu, sum; 1729 1730 switch (which) { 1731 case MNT_COUNT_REF: 1732 sum = mp->mnt_ref; 1733 break; 1734 case MNT_COUNT_LOCKREF: 1735 sum = mp->mnt_lockref; 1736 break; 1737 case MNT_COUNT_WRITEOPCOUNT: 1738 sum = mp->mnt_writeopcount; 1739 break; 1740 } 1741 1742 CPU_FOREACH(cpu) { 1743 mpcpu = vfs_mount_pcpu_remote(mp, cpu); 1744 switch (which) { 1745 case MNT_COUNT_REF: 1746 sum += mpcpu->mntp_ref; 1747 break; 1748 case MNT_COUNT_LOCKREF: 1749 sum += mpcpu->mntp_lockref; 1750 break; 1751 case MNT_COUNT_WRITEOPCOUNT: 1752 sum += mpcpu->mntp_writeopcount; 1753 break; 1754 } 1755 } 1756 return (sum); 1757 } 1758 1759 /* 1760 * Do the actual filesystem unmount. 1761 */ 1762 int 1763 dounmount(struct mount *mp, int flags, struct thread *td) 1764 { 1765 struct vnode *coveredvp, *rootvp; 1766 int error; 1767 uint64_t async_flag; 1768 int mnt_gen_r; 1769 1770 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1771 mnt_gen_r = mp->mnt_gen; 1772 VI_LOCK(coveredvp); 1773 vholdl(coveredvp); 1774 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1775 /* 1776 * Check for mp being unmounted while waiting for the 1777 * covered vnode lock. 1778 */ 1779 if (coveredvp->v_mountedhere != mp || 1780 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1781 VOP_UNLOCK(coveredvp); 1782 vdrop(coveredvp); 1783 vfs_rel(mp); 1784 return (EBUSY); 1785 } 1786 } 1787 1788 /* 1789 * Only privileged root, or (if MNT_USER is set) the user that did the 1790 * original mount is permitted to unmount this filesystem. 1791 */ 1792 error = vfs_suser(mp, td); 1793 if (error != 0) { 1794 if (coveredvp != NULL) { 1795 VOP_UNLOCK(coveredvp); 1796 vdrop(coveredvp); 1797 } 1798 vfs_rel(mp); 1799 return (error); 1800 } 1801 1802 vfs_op_enter(mp); 1803 1804 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1805 MNT_ILOCK(mp); 1806 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1807 (mp->mnt_flag & MNT_UPDATE) != 0 || 1808 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1809 dounmount_cleanup(mp, coveredvp, 0); 1810 return (EBUSY); 1811 } 1812 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1813 rootvp = vfs_cache_root_clear(mp); 1814 if (coveredvp != NULL) 1815 vn_seqc_write_begin(coveredvp); 1816 if (flags & MNT_NONBUSY) { 1817 MNT_IUNLOCK(mp); 1818 error = vfs_check_usecounts(mp); 1819 MNT_ILOCK(mp); 1820 if (error != 0) { 1821 vn_seqc_write_end(coveredvp); 1822 dounmount_cleanup(mp, coveredvp, MNTK_UNMOUNT); 1823 if (rootvp != NULL) { 1824 vn_seqc_write_end(rootvp); 1825 vrele(rootvp); 1826 } 1827 return (error); 1828 } 1829 } 1830 /* Allow filesystems to detect that a forced unmount is in progress. */ 1831 if (flags & MNT_FORCE) { 1832 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1833 MNT_IUNLOCK(mp); 1834 /* 1835 * Must be done after setting MNTK_UNMOUNTF and before 1836 * waiting for mnt_lockref to become 0. 1837 */ 1838 VFS_PURGE(mp); 1839 MNT_ILOCK(mp); 1840 } 1841 error = 0; 1842 if (mp->mnt_lockref) { 1843 mp->mnt_kern_flag |= MNTK_DRAINING; 1844 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1845 "mount drain", 0); 1846 } 1847 MNT_IUNLOCK(mp); 1848 KASSERT(mp->mnt_lockref == 0, 1849 ("%s: invalid lock refcount in the drain path @ %s:%d", 1850 __func__, __FILE__, __LINE__)); 1851 KASSERT(error == 0, 1852 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1853 __func__, __FILE__, __LINE__)); 1854 1855 /* 1856 * We want to keep the vnode around so that we can vn_seqc_write_end 1857 * after we are done with unmount. Downgrade our reference to a mere 1858 * hold count so that we don't interefere with anything. 1859 */ 1860 if (rootvp != NULL) { 1861 vhold(rootvp); 1862 vrele(rootvp); 1863 } 1864 1865 if (mp->mnt_flag & MNT_EXPUBLIC) 1866 vfs_setpublicfs(NULL, NULL, NULL); 1867 1868 vfs_periodic(mp, MNT_WAIT); 1869 MNT_ILOCK(mp); 1870 async_flag = mp->mnt_flag & MNT_ASYNC; 1871 mp->mnt_flag &= ~MNT_ASYNC; 1872 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1873 MNT_IUNLOCK(mp); 1874 vfs_deallocate_syncvnode(mp); 1875 error = VFS_UNMOUNT(mp, flags); 1876 vn_finished_write(mp); 1877 /* 1878 * If we failed to flush the dirty blocks for this mount point, 1879 * undo all the cdir/rdir and rootvnode changes we made above. 1880 * Unless we failed to do so because the device is reporting that 1881 * it doesn't exist anymore. 1882 */ 1883 if (error && error != ENXIO) { 1884 MNT_ILOCK(mp); 1885 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1886 MNT_IUNLOCK(mp); 1887 vfs_allocate_syncvnode(mp); 1888 MNT_ILOCK(mp); 1889 } 1890 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1891 mp->mnt_flag |= async_flag; 1892 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1893 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1894 mp->mnt_kern_flag |= MNTK_ASYNC; 1895 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1896 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1897 wakeup(mp); 1898 } 1899 vfs_op_exit_locked(mp); 1900 MNT_IUNLOCK(mp); 1901 if (coveredvp) { 1902 vn_seqc_write_end(coveredvp); 1903 VOP_UNLOCK(coveredvp); 1904 vdrop(coveredvp); 1905 } 1906 if (rootvp != NULL) { 1907 vn_seqc_write_end(rootvp); 1908 vdrop(rootvp); 1909 } 1910 return (error); 1911 } 1912 mtx_lock(&mountlist_mtx); 1913 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1914 mtx_unlock(&mountlist_mtx); 1915 EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td); 1916 if (coveredvp != NULL) { 1917 VI_LOCK(coveredvp); 1918 vn_irflag_unset_locked(coveredvp, VIRF_MOUNTPOINT); 1919 coveredvp->v_mountedhere = NULL; 1920 vn_seqc_write_end_locked(coveredvp); 1921 VI_UNLOCK(coveredvp); 1922 VOP_UNLOCK(coveredvp); 1923 vdrop(coveredvp); 1924 } 1925 mount_devctl_event("UNMOUNT", mp, false); 1926 if (rootvp != NULL) { 1927 vn_seqc_write_end(rootvp); 1928 vdrop(rootvp); 1929 } 1930 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1931 if (rootvnode != NULL && mp == rootvnode->v_mount) { 1932 vrele(rootvnode); 1933 rootvnode = NULL; 1934 } 1935 if (mp == rootdevmp) 1936 rootdevmp = NULL; 1937 vfs_mount_destroy(mp); 1938 return (0); 1939 } 1940 1941 /* 1942 * Report errors during filesystem mounting. 1943 */ 1944 void 1945 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1946 { 1947 struct vfsoptlist *moptlist = mp->mnt_optnew; 1948 va_list ap; 1949 int error, len; 1950 char *errmsg; 1951 1952 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1953 if (error || errmsg == NULL || len <= 0) 1954 return; 1955 1956 va_start(ap, fmt); 1957 vsnprintf(errmsg, (size_t)len, fmt, ap); 1958 va_end(ap); 1959 } 1960 1961 void 1962 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1963 { 1964 va_list ap; 1965 int error, len; 1966 char *errmsg; 1967 1968 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1969 if (error || errmsg == NULL || len <= 0) 1970 return; 1971 1972 va_start(ap, fmt); 1973 vsnprintf(errmsg, (size_t)len, fmt, ap); 1974 va_end(ap); 1975 } 1976 1977 /* 1978 * --------------------------------------------------------------------- 1979 * Functions for querying mount options/arguments from filesystems. 1980 */ 1981 1982 /* 1983 * Check that no unknown options are given 1984 */ 1985 int 1986 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1987 { 1988 struct vfsopt *opt; 1989 char errmsg[255]; 1990 const char **t, *p, *q; 1991 int ret = 0; 1992 1993 TAILQ_FOREACH(opt, opts, link) { 1994 p = opt->name; 1995 q = NULL; 1996 if (p[0] == 'n' && p[1] == 'o') 1997 q = p + 2; 1998 for(t = global_opts; *t != NULL; t++) { 1999 if (strcmp(*t, p) == 0) 2000 break; 2001 if (q != NULL) { 2002 if (strcmp(*t, q) == 0) 2003 break; 2004 } 2005 } 2006 if (*t != NULL) 2007 continue; 2008 for(t = legal; *t != NULL; t++) { 2009 if (strcmp(*t, p) == 0) 2010 break; 2011 if (q != NULL) { 2012 if (strcmp(*t, q) == 0) 2013 break; 2014 } 2015 } 2016 if (*t != NULL) 2017 continue; 2018 snprintf(errmsg, sizeof(errmsg), 2019 "mount option <%s> is unknown", p); 2020 ret = EINVAL; 2021 } 2022 if (ret != 0) { 2023 TAILQ_FOREACH(opt, opts, link) { 2024 if (strcmp(opt->name, "errmsg") == 0) { 2025 strncpy((char *)opt->value, errmsg, opt->len); 2026 break; 2027 } 2028 } 2029 if (opt == NULL) 2030 printf("%s\n", errmsg); 2031 } 2032 return (ret); 2033 } 2034 2035 /* 2036 * Get a mount option by its name. 2037 * 2038 * Return 0 if the option was found, ENOENT otherwise. 2039 * If len is non-NULL it will be filled with the length 2040 * of the option. If buf is non-NULL, it will be filled 2041 * with the address of the option. 2042 */ 2043 int 2044 vfs_getopt(struct vfsoptlist *opts, const char *name, void **buf, int *len) 2045 { 2046 struct vfsopt *opt; 2047 2048 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2049 2050 TAILQ_FOREACH(opt, opts, link) { 2051 if (strcmp(name, opt->name) == 0) { 2052 opt->seen = 1; 2053 if (len != NULL) 2054 *len = opt->len; 2055 if (buf != NULL) 2056 *buf = opt->value; 2057 return (0); 2058 } 2059 } 2060 return (ENOENT); 2061 } 2062 2063 int 2064 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 2065 { 2066 struct vfsopt *opt; 2067 2068 if (opts == NULL) 2069 return (-1); 2070 2071 TAILQ_FOREACH(opt, opts, link) { 2072 if (strcmp(name, opt->name) == 0) { 2073 opt->seen = 1; 2074 return (opt->pos); 2075 } 2076 } 2077 return (-1); 2078 } 2079 2080 int 2081 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 2082 { 2083 char *opt_value, *vtp; 2084 quad_t iv; 2085 int error, opt_len; 2086 2087 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 2088 if (error != 0) 2089 return (error); 2090 if (opt_len == 0 || opt_value == NULL) 2091 return (EINVAL); 2092 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 2093 return (EINVAL); 2094 iv = strtoq(opt_value, &vtp, 0); 2095 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 2096 return (EINVAL); 2097 if (iv < 0) 2098 return (EINVAL); 2099 switch (vtp[0]) { 2100 case 't': case 'T': 2101 iv *= 1024; 2102 /* FALLTHROUGH */ 2103 case 'g': case 'G': 2104 iv *= 1024; 2105 /* FALLTHROUGH */ 2106 case 'm': case 'M': 2107 iv *= 1024; 2108 /* FALLTHROUGH */ 2109 case 'k': case 'K': 2110 iv *= 1024; 2111 case '\0': 2112 break; 2113 default: 2114 return (EINVAL); 2115 } 2116 *value = iv; 2117 2118 return (0); 2119 } 2120 2121 char * 2122 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 2123 { 2124 struct vfsopt *opt; 2125 2126 *error = 0; 2127 TAILQ_FOREACH(opt, opts, link) { 2128 if (strcmp(name, opt->name) != 0) 2129 continue; 2130 opt->seen = 1; 2131 if (opt->len == 0 || 2132 ((char *)opt->value)[opt->len - 1] != '\0') { 2133 *error = EINVAL; 2134 return (NULL); 2135 } 2136 return (opt->value); 2137 } 2138 *error = ENOENT; 2139 return (NULL); 2140 } 2141 2142 int 2143 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 2144 uint64_t val) 2145 { 2146 struct vfsopt *opt; 2147 2148 TAILQ_FOREACH(opt, opts, link) { 2149 if (strcmp(name, opt->name) == 0) { 2150 opt->seen = 1; 2151 if (w != NULL) 2152 *w |= val; 2153 return (1); 2154 } 2155 } 2156 if (w != NULL) 2157 *w &= ~val; 2158 return (0); 2159 } 2160 2161 int 2162 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 2163 { 2164 va_list ap; 2165 struct vfsopt *opt; 2166 int ret; 2167 2168 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2169 2170 TAILQ_FOREACH(opt, opts, link) { 2171 if (strcmp(name, opt->name) != 0) 2172 continue; 2173 opt->seen = 1; 2174 if (opt->len == 0 || opt->value == NULL) 2175 return (0); 2176 if (((char *)opt->value)[opt->len - 1] != '\0') 2177 return (0); 2178 va_start(ap, fmt); 2179 ret = vsscanf(opt->value, fmt, ap); 2180 va_end(ap); 2181 return (ret); 2182 } 2183 return (0); 2184 } 2185 2186 int 2187 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 2188 { 2189 struct vfsopt *opt; 2190 2191 TAILQ_FOREACH(opt, opts, link) { 2192 if (strcmp(name, opt->name) != 0) 2193 continue; 2194 opt->seen = 1; 2195 if (opt->value == NULL) 2196 opt->len = len; 2197 else { 2198 if (opt->len != len) 2199 return (EINVAL); 2200 bcopy(value, opt->value, len); 2201 } 2202 return (0); 2203 } 2204 return (ENOENT); 2205 } 2206 2207 int 2208 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 2209 { 2210 struct vfsopt *opt; 2211 2212 TAILQ_FOREACH(opt, opts, link) { 2213 if (strcmp(name, opt->name) != 0) 2214 continue; 2215 opt->seen = 1; 2216 if (opt->value == NULL) 2217 opt->len = len; 2218 else { 2219 if (opt->len < len) 2220 return (EINVAL); 2221 opt->len = len; 2222 bcopy(value, opt->value, len); 2223 } 2224 return (0); 2225 } 2226 return (ENOENT); 2227 } 2228 2229 int 2230 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2231 { 2232 struct vfsopt *opt; 2233 2234 TAILQ_FOREACH(opt, opts, link) { 2235 if (strcmp(name, opt->name) != 0) 2236 continue; 2237 opt->seen = 1; 2238 if (opt->value == NULL) 2239 opt->len = strlen(value) + 1; 2240 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2241 return (EINVAL); 2242 return (0); 2243 } 2244 return (ENOENT); 2245 } 2246 2247 /* 2248 * Find and copy a mount option. 2249 * 2250 * The size of the buffer has to be specified 2251 * in len, if it is not the same length as the 2252 * mount option, EINVAL is returned. 2253 * Returns ENOENT if the option is not found. 2254 */ 2255 int 2256 vfs_copyopt(struct vfsoptlist *opts, const char *name, void *dest, int len) 2257 { 2258 struct vfsopt *opt; 2259 2260 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2261 2262 TAILQ_FOREACH(opt, opts, link) { 2263 if (strcmp(name, opt->name) == 0) { 2264 opt->seen = 1; 2265 if (len != opt->len) 2266 return (EINVAL); 2267 bcopy(opt->value, dest, opt->len); 2268 return (0); 2269 } 2270 } 2271 return (ENOENT); 2272 } 2273 2274 int 2275 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2276 { 2277 2278 /* 2279 * Filesystems only fill in part of the structure for updates, we 2280 * have to read the entirety first to get all content. 2281 */ 2282 if (sbp != &mp->mnt_stat) 2283 memcpy(sbp, &mp->mnt_stat, sizeof(*sbp)); 2284 2285 /* 2286 * Set these in case the underlying filesystem fails to do so. 2287 */ 2288 sbp->f_version = STATFS_VERSION; 2289 sbp->f_namemax = NAME_MAX; 2290 sbp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK; 2291 2292 return (mp->mnt_op->vfs_statfs(mp, sbp)); 2293 } 2294 2295 void 2296 vfs_mountedfrom(struct mount *mp, const char *from) 2297 { 2298 2299 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2300 strlcpy(mp->mnt_stat.f_mntfromname, from, 2301 sizeof mp->mnt_stat.f_mntfromname); 2302 } 2303 2304 /* 2305 * --------------------------------------------------------------------- 2306 * This is the api for building mount args and mounting filesystems from 2307 * inside the kernel. 2308 * 2309 * The API works by accumulation of individual args. First error is 2310 * latched. 2311 * 2312 * XXX: should be documented in new manpage kernel_mount(9) 2313 */ 2314 2315 /* A memory allocation which must be freed when we are done */ 2316 struct mntaarg { 2317 SLIST_ENTRY(mntaarg) next; 2318 }; 2319 2320 /* The header for the mount arguments */ 2321 struct mntarg { 2322 struct iovec *v; 2323 int len; 2324 int error; 2325 SLIST_HEAD(, mntaarg) list; 2326 }; 2327 2328 /* 2329 * Add a boolean argument. 2330 * 2331 * flag is the boolean value. 2332 * name must start with "no". 2333 */ 2334 struct mntarg * 2335 mount_argb(struct mntarg *ma, int flag, const char *name) 2336 { 2337 2338 KASSERT(name[0] == 'n' && name[1] == 'o', 2339 ("mount_argb(...,%s): name must start with 'no'", name)); 2340 2341 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2342 } 2343 2344 /* 2345 * Add an argument printf style 2346 */ 2347 struct mntarg * 2348 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2349 { 2350 va_list ap; 2351 struct mntaarg *maa; 2352 struct sbuf *sb; 2353 int len; 2354 2355 if (ma == NULL) { 2356 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2357 SLIST_INIT(&ma->list); 2358 } 2359 if (ma->error) 2360 return (ma); 2361 2362 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2363 M_MOUNT, M_WAITOK); 2364 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2365 ma->v[ma->len].iov_len = strlen(name) + 1; 2366 ma->len++; 2367 2368 sb = sbuf_new_auto(); 2369 va_start(ap, fmt); 2370 sbuf_vprintf(sb, fmt, ap); 2371 va_end(ap); 2372 sbuf_finish(sb); 2373 len = sbuf_len(sb) + 1; 2374 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2375 SLIST_INSERT_HEAD(&ma->list, maa, next); 2376 bcopy(sbuf_data(sb), maa + 1, len); 2377 sbuf_delete(sb); 2378 2379 ma->v[ma->len].iov_base = maa + 1; 2380 ma->v[ma->len].iov_len = len; 2381 ma->len++; 2382 2383 return (ma); 2384 } 2385 2386 /* 2387 * Add an argument which is a userland string. 2388 */ 2389 struct mntarg * 2390 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2391 { 2392 struct mntaarg *maa; 2393 char *tbuf; 2394 2395 if (val == NULL) 2396 return (ma); 2397 if (ma == NULL) { 2398 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2399 SLIST_INIT(&ma->list); 2400 } 2401 if (ma->error) 2402 return (ma); 2403 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2404 SLIST_INSERT_HEAD(&ma->list, maa, next); 2405 tbuf = (void *)(maa + 1); 2406 ma->error = copyinstr(val, tbuf, len, NULL); 2407 return (mount_arg(ma, name, tbuf, -1)); 2408 } 2409 2410 /* 2411 * Plain argument. 2412 * 2413 * If length is -1, treat value as a C string. 2414 */ 2415 struct mntarg * 2416 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2417 { 2418 2419 if (ma == NULL) { 2420 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2421 SLIST_INIT(&ma->list); 2422 } 2423 if (ma->error) 2424 return (ma); 2425 2426 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2427 M_MOUNT, M_WAITOK); 2428 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2429 ma->v[ma->len].iov_len = strlen(name) + 1; 2430 ma->len++; 2431 2432 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2433 if (len < 0) 2434 ma->v[ma->len].iov_len = strlen(val) + 1; 2435 else 2436 ma->v[ma->len].iov_len = len; 2437 ma->len++; 2438 return (ma); 2439 } 2440 2441 /* 2442 * Free a mntarg structure 2443 */ 2444 static void 2445 free_mntarg(struct mntarg *ma) 2446 { 2447 struct mntaarg *maa; 2448 2449 while (!SLIST_EMPTY(&ma->list)) { 2450 maa = SLIST_FIRST(&ma->list); 2451 SLIST_REMOVE_HEAD(&ma->list, next); 2452 free(maa, M_MOUNT); 2453 } 2454 free(ma->v, M_MOUNT); 2455 free(ma, M_MOUNT); 2456 } 2457 2458 /* 2459 * Mount a filesystem 2460 */ 2461 int 2462 kernel_mount(struct mntarg *ma, uint64_t flags) 2463 { 2464 struct uio auio; 2465 int error; 2466 2467 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2468 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2469 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2470 2471 auio.uio_iov = ma->v; 2472 auio.uio_iovcnt = ma->len; 2473 auio.uio_segflg = UIO_SYSSPACE; 2474 2475 error = ma->error; 2476 if (!error) 2477 error = vfs_donmount(curthread, flags, &auio); 2478 free_mntarg(ma); 2479 return (error); 2480 } 2481 2482 /* 2483 * A printflike function to mount a filesystem. 2484 */ 2485 int 2486 kernel_vmount(int flags, ...) 2487 { 2488 struct mntarg *ma = NULL; 2489 va_list ap; 2490 const char *cp; 2491 const void *vp; 2492 int error; 2493 2494 va_start(ap, flags); 2495 for (;;) { 2496 cp = va_arg(ap, const char *); 2497 if (cp == NULL) 2498 break; 2499 vp = va_arg(ap, const void *); 2500 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2501 } 2502 va_end(ap); 2503 2504 error = kernel_mount(ma, flags); 2505 return (error); 2506 } 2507 2508 /* Map from mount options to printable formats. */ 2509 static struct mntoptnames optnames[] = { 2510 MNTOPT_NAMES 2511 }; 2512 2513 #define DEVCTL_LEN 1024 2514 static void 2515 mount_devctl_event(const char *type, struct mount *mp, bool donew) 2516 { 2517 const uint8_t *cp; 2518 struct mntoptnames *fp; 2519 struct sbuf sb; 2520 struct statfs *sfp = &mp->mnt_stat; 2521 char *buf; 2522 2523 buf = malloc(DEVCTL_LEN, M_MOUNT, M_NOWAIT); 2524 if (buf == NULL) 2525 return; 2526 sbuf_new(&sb, buf, DEVCTL_LEN, SBUF_FIXEDLEN); 2527 sbuf_cpy(&sb, "mount-point=\""); 2528 devctl_safe_quote_sb(&sb, sfp->f_mntonname); 2529 sbuf_cat(&sb, "\" mount-dev=\""); 2530 devctl_safe_quote_sb(&sb, sfp->f_mntfromname); 2531 sbuf_cat(&sb, "\" mount-type=\""); 2532 devctl_safe_quote_sb(&sb, sfp->f_fstypename); 2533 sbuf_cat(&sb, "\" fsid=0x"); 2534 cp = (const uint8_t *)&sfp->f_fsid.val[0]; 2535 for (int i = 0; i < sizeof(sfp->f_fsid); i++) 2536 sbuf_printf(&sb, "%02x", cp[i]); 2537 sbuf_printf(&sb, " owner=%u flags=\"", sfp->f_owner); 2538 for (fp = optnames; fp->o_opt != 0; fp++) { 2539 if ((mp->mnt_flag & fp->o_opt) != 0) { 2540 sbuf_cat(&sb, fp->o_name); 2541 sbuf_putc(&sb, ';'); 2542 } 2543 } 2544 sbuf_putc(&sb, '"'); 2545 sbuf_finish(&sb); 2546 2547 /* 2548 * Options are not published because the form of the options depends on 2549 * the file system and may include binary data. In addition, they don't 2550 * necessarily provide enough useful information to be actionable when 2551 * devd processes them. 2552 */ 2553 2554 if (sbuf_error(&sb) == 0) 2555 devctl_notify("VFS", "FS", type, sbuf_data(&sb)); 2556 sbuf_delete(&sb); 2557 free(buf, M_MOUNT); 2558 } 2559 2560 /* 2561 * Suspend write operations on all local writeable filesystems. Does 2562 * full sync of them in the process. 2563 * 2564 * Iterate over the mount points in reverse order, suspending most 2565 * recently mounted filesystems first. It handles a case where a 2566 * filesystem mounted from a md(4) vnode-backed device should be 2567 * suspended before the filesystem that owns the vnode. 2568 */ 2569 void 2570 suspend_all_fs(void) 2571 { 2572 struct mount *mp; 2573 int error; 2574 2575 mtx_lock(&mountlist_mtx); 2576 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 2577 error = vfs_busy(mp, MBF_MNTLSTLOCK | MBF_NOWAIT); 2578 if (error != 0) 2579 continue; 2580 if ((mp->mnt_flag & (MNT_RDONLY | MNT_LOCAL)) != MNT_LOCAL || 2581 (mp->mnt_kern_flag & MNTK_SUSPEND) != 0) { 2582 mtx_lock(&mountlist_mtx); 2583 vfs_unbusy(mp); 2584 continue; 2585 } 2586 error = vfs_write_suspend(mp, 0); 2587 if (error == 0) { 2588 MNT_ILOCK(mp); 2589 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND_ALL) == 0); 2590 mp->mnt_kern_flag |= MNTK_SUSPEND_ALL; 2591 MNT_IUNLOCK(mp); 2592 mtx_lock(&mountlist_mtx); 2593 } else { 2594 printf("suspend of %s failed, error %d\n", 2595 mp->mnt_stat.f_mntonname, error); 2596 mtx_lock(&mountlist_mtx); 2597 vfs_unbusy(mp); 2598 } 2599 } 2600 mtx_unlock(&mountlist_mtx); 2601 } 2602 2603 void 2604 resume_all_fs(void) 2605 { 2606 struct mount *mp; 2607 2608 mtx_lock(&mountlist_mtx); 2609 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2610 if ((mp->mnt_kern_flag & MNTK_SUSPEND_ALL) == 0) 2611 continue; 2612 mtx_unlock(&mountlist_mtx); 2613 MNT_ILOCK(mp); 2614 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) != 0); 2615 mp->mnt_kern_flag &= ~MNTK_SUSPEND_ALL; 2616 MNT_IUNLOCK(mp); 2617 vfs_write_resume(mp, 0); 2618 mtx_lock(&mountlist_mtx); 2619 vfs_unbusy(mp); 2620 } 2621 mtx_unlock(&mountlist_mtx); 2622 }
Cache object: f6068f8bf9b38de58cc441433e263e19
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