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 * 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 for (i = 0; mp->mnt_ref && i < 3; i++) 512 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 513 /* 514 * This will always cause a 3 second delay in rebooting due to 515 * refs on the root mountpoint that never go away. Most of these 516 * are held by init which never exits. 517 */ 518 if (i == 3 && (!rebooting || bootverbose)) 519 printf("Mount point %s had %d dangling refs\n", 520 mp->mnt_stat.f_mntonname, mp->mnt_ref); 521 if (mp->mnt_holdcnt != 0) { 522 printf("Waiting for mount point to be unheld\n"); 523 while (mp->mnt_holdcnt != 0) { 524 mp->mnt_holdcntwaiters++; 525 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 526 PZERO, "mntdestroy", 0); 527 mp->mnt_holdcntwaiters--; 528 } 529 printf("mount point unheld\n"); 530 } 531 if (mp->mnt_writeopcount > 0) { 532 printf("Waiting for mount point write ops\n"); 533 while (mp->mnt_writeopcount > 0) { 534 mp->mnt_kern_flag |= MNTK_SUSPEND; 535 msleep(&mp->mnt_writeopcount, 536 MNT_MTX(mp), 537 PZERO, "mntdestroy2", 0); 538 } 539 printf("mount point write ops completed\n"); 540 } 541 if (mp->mnt_secondary_writes > 0) { 542 printf("Waiting for mount point secondary write ops\n"); 543 while (mp->mnt_secondary_writes > 0) { 544 mp->mnt_kern_flag |= MNTK_SUSPEND; 545 msleep(&mp->mnt_secondary_writes, 546 MNT_MTX(mp), 547 PZERO, "mntdestroy3", 0); 548 } 549 printf("mount point secondary write ops completed\n"); 550 } 551 MNT_IUNLOCK(mp); 552 mp->mnt_vfc->vfc_refcount--; 553 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 554 struct vnode *vp; 555 556 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 557 vprint("", vp); 558 panic("unmount: dangling vnode"); 559 } 560 MNT_ILOCK(mp); 561 if (mp->mnt_kern_flag & MNTK_MWAIT) 562 wakeup(mp); 563 if (mp->mnt_writeopcount != 0) 564 panic("vfs_mount_destroy: nonzero writeopcount"); 565 if (mp->mnt_secondary_writes != 0) 566 panic("vfs_mount_destroy: nonzero secondary_writes"); 567 if (mp->mnt_nvnodelistsize != 0) 568 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 569 mp->mnt_writeopcount = -1000; 570 mp->mnt_nvnodelistsize = -1000; 571 mp->mnt_secondary_writes = -1000; 572 MNT_IUNLOCK(mp); 573 #ifdef MAC 574 mac_destroy_mount(mp); 575 #endif 576 if (mp->mnt_opt != NULL) 577 vfs_freeopts(mp->mnt_opt); 578 crfree(mp->mnt_cred); 579 uma_zfree(mount_zone, mp); 580 } 581 582 int 583 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 584 { 585 struct vfsoptlist *optlist; 586 struct vfsopt *opt, *noro_opt, *tmp_opt; 587 char *fstype, *fspath, *errmsg; 588 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 589 int has_rw, has_noro; 590 591 errmsg = NULL; 592 errmsg_len = 0; 593 errmsg_pos = -1; 594 has_rw = 0; 595 has_noro = 0; 596 597 error = vfs_buildopts(fsoptions, &optlist); 598 if (error) 599 return (error); 600 601 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 602 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 603 604 /* 605 * We need these two options before the others, 606 * and they are mandatory for any filesystem. 607 * Ensure they are NUL terminated as well. 608 */ 609 fstypelen = 0; 610 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 611 if (error || fstype[fstypelen - 1] != '\0') { 612 error = EINVAL; 613 if (errmsg != NULL) 614 strncpy(errmsg, "Invalid fstype", errmsg_len); 615 goto bail; 616 } 617 fspathlen = 0; 618 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 619 if (error || fspath[fspathlen - 1] != '\0') { 620 error = EINVAL; 621 if (errmsg != NULL) 622 strncpy(errmsg, "Invalid fspath", errmsg_len); 623 goto bail; 624 } 625 626 /* 627 * We need to see if we have the "update" option 628 * before we call vfs_domount(), since vfs_domount() has special 629 * logic based on MNT_UPDATE. This is very important 630 * when we want to update the root filesystem. 631 */ 632 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 633 if (strcmp(opt->name, "update") == 0) { 634 fsflags |= MNT_UPDATE; 635 vfs_freeopt(optlist, opt); 636 } 637 else if (strcmp(opt->name, "async") == 0) 638 fsflags |= MNT_ASYNC; 639 else if (strcmp(opt->name, "force") == 0) { 640 fsflags |= MNT_FORCE; 641 vfs_freeopt(optlist, opt); 642 } 643 else if (strcmp(opt->name, "reload") == 0) { 644 fsflags |= MNT_RELOAD; 645 vfs_freeopt(optlist, opt); 646 } 647 else if (strcmp(opt->name, "multilabel") == 0) 648 fsflags |= MNT_MULTILABEL; 649 else if (strcmp(opt->name, "noasync") == 0) 650 fsflags &= ~MNT_ASYNC; 651 else if (strcmp(opt->name, "noatime") == 0) 652 fsflags |= MNT_NOATIME; 653 else if (strcmp(opt->name, "atime") == 0) { 654 free(opt->name, M_MOUNT); 655 opt->name = strdup("nonoatime", M_MOUNT); 656 } 657 else if (strcmp(opt->name, "noclusterr") == 0) 658 fsflags |= MNT_NOCLUSTERR; 659 else if (strcmp(opt->name, "clusterr") == 0) { 660 free(opt->name, M_MOUNT); 661 opt->name = strdup("nonoclusterr", M_MOUNT); 662 } 663 else if (strcmp(opt->name, "noclusterw") == 0) 664 fsflags |= MNT_NOCLUSTERW; 665 else if (strcmp(opt->name, "clusterw") == 0) { 666 free(opt->name, M_MOUNT); 667 opt->name = strdup("nonoclusterw", M_MOUNT); 668 } 669 else if (strcmp(opt->name, "noexec") == 0) 670 fsflags |= MNT_NOEXEC; 671 else if (strcmp(opt->name, "exec") == 0) { 672 free(opt->name, M_MOUNT); 673 opt->name = strdup("nonoexec", M_MOUNT); 674 } 675 else if (strcmp(opt->name, "nosuid") == 0) 676 fsflags |= MNT_NOSUID; 677 else if (strcmp(opt->name, "suid") == 0) { 678 free(opt->name, M_MOUNT); 679 opt->name = strdup("nonosuid", M_MOUNT); 680 } 681 else if (strcmp(opt->name, "nosymfollow") == 0) 682 fsflags |= MNT_NOSYMFOLLOW; 683 else if (strcmp(opt->name, "symfollow") == 0) { 684 free(opt->name, M_MOUNT); 685 opt->name = strdup("nonosymfollow", M_MOUNT); 686 } 687 else if (strcmp(opt->name, "noro") == 0) { 688 fsflags &= ~MNT_RDONLY; 689 has_noro = 1; 690 } 691 else if (strcmp(opt->name, "rw") == 0) { 692 fsflags &= ~MNT_RDONLY; 693 has_rw = 1; 694 } 695 else if (strcmp(opt->name, "ro") == 0) 696 fsflags |= MNT_RDONLY; 697 else if (strcmp(opt->name, "rdonly") == 0) { 698 free(opt->name, M_MOUNT); 699 opt->name = strdup("ro", M_MOUNT); 700 fsflags |= MNT_RDONLY; 701 } 702 else if (strcmp(opt->name, "suiddir") == 0) 703 fsflags |= MNT_SUIDDIR; 704 else if (strcmp(opt->name, "sync") == 0) 705 fsflags |= MNT_SYNCHRONOUS; 706 else if (strcmp(opt->name, "union") == 0) 707 fsflags |= MNT_UNION; 708 } 709 710 /* 711 * If "rw" was specified as a mount option, and we 712 * are trying to update a mount-point from "ro" to "rw", 713 * we need a mount option "noro", since in vfs_mergeopts(), 714 * "noro" will cancel "ro", but "rw" will not do anything. 715 */ 716 if (has_rw && !has_noro) { 717 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 718 noro_opt->name = strdup("noro", M_MOUNT); 719 noro_opt->value = NULL; 720 noro_opt->len = 0; 721 TAILQ_INSERT_TAIL(optlist, noro_opt, link); 722 } 723 724 /* 725 * Be ultra-paranoid about making sure the type and fspath 726 * variables will fit in our mp buffers, including the 727 * terminating NUL. 728 */ 729 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 730 error = ENAMETOOLONG; 731 goto bail; 732 } 733 734 mtx_lock(&Giant); 735 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 736 mtx_unlock(&Giant); 737 bail: 738 /* copyout the errmsg */ 739 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 740 && errmsg_len > 0 && errmsg != NULL) { 741 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 742 bcopy(errmsg, 743 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 744 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 745 } else { 746 copyout(errmsg, 747 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 748 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 749 } 750 } 751 752 if (error != 0) 753 vfs_freeopts(optlist); 754 return (error); 755 } 756 757 /* 758 * Old mount API. 759 */ 760 #ifndef _SYS_SYSPROTO_H_ 761 struct mount_args { 762 char *type; 763 char *path; 764 int flags; 765 caddr_t data; 766 }; 767 #endif 768 /* ARGSUSED */ 769 int 770 mount(td, uap) 771 struct thread *td; 772 struct mount_args /* { 773 char *type; 774 char *path; 775 int flags; 776 caddr_t data; 777 } */ *uap; 778 { 779 char *fstype; 780 struct vfsconf *vfsp = NULL; 781 struct mntarg *ma = NULL; 782 int error; 783 784 AUDIT_ARG(fflags, uap->flags); 785 786 /* 787 * Filter out MNT_ROOTFS. We do not want clients of mount() in 788 * userspace to set this flag, but we must filter it out if we want 789 * MNT_UPDATE on the root file system to work. 790 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 791 */ 792 uap->flags &= ~MNT_ROOTFS; 793 794 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 795 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 796 if (error) { 797 free(fstype, M_TEMP); 798 return (error); 799 } 800 801 AUDIT_ARG(text, fstype); 802 mtx_lock(&Giant); 803 vfsp = vfs_byname_kld(fstype, td, &error); 804 free(fstype, M_TEMP); 805 if (vfsp == NULL) { 806 mtx_unlock(&Giant); 807 return (ENOENT); 808 } 809 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 810 mtx_unlock(&Giant); 811 return (EOPNOTSUPP); 812 } 813 814 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 815 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 816 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 817 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 818 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 819 820 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 821 mtx_unlock(&Giant); 822 return (error); 823 } 824 825 826 /* 827 * vfs_domount(): actually attempt a filesystem mount. 828 */ 829 static int 830 vfs_domount( 831 struct thread *td, /* Calling thread. */ 832 const char *fstype, /* Filesystem type. */ 833 char *fspath, /* Mount path. */ 834 int fsflags, /* Flags common to all filesystems. */ 835 void *fsdata /* Options local to the filesystem. */ 836 ) 837 { 838 struct vnode *vp; 839 struct mount *mp; 840 struct vfsconf *vfsp; 841 struct export_args export; 842 int error, flag = 0; 843 struct vattr va; 844 struct nameidata nd; 845 846 mtx_assert(&Giant, MA_OWNED); 847 /* 848 * Be ultra-paranoid about making sure the type and fspath 849 * variables will fit in our mp buffers, including the 850 * terminating NUL. 851 */ 852 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 853 return (ENAMETOOLONG); 854 855 if (jailed(td->td_ucred) || usermount == 0) { 856 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 857 return (error); 858 } 859 860 /* 861 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 862 */ 863 if (fsflags & MNT_EXPORTED) { 864 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 865 if (error) 866 return (error); 867 } 868 if (fsflags & MNT_SUIDDIR) { 869 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 870 if (error) 871 return (error); 872 } 873 /* 874 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 875 */ 876 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 877 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 878 fsflags |= MNT_NOSUID | MNT_USER; 879 } 880 881 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 882 vfsp = NULL; 883 if ((fsflags & MNT_UPDATE) == 0) { 884 /* Don't try to load KLDs if we're mounting the root. */ 885 if (fsflags & MNT_ROOTFS) 886 vfsp = vfs_byname(fstype); 887 else 888 vfsp = vfs_byname_kld(fstype, td, &error); 889 if (vfsp == NULL) 890 return (ENODEV); 891 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 892 return (EPERM); 893 } 894 /* 895 * Get vnode to be covered 896 */ 897 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 898 fspath, td); 899 if ((error = namei(&nd)) != 0) 900 return (error); 901 NDFREE(&nd, NDF_ONLY_PNBUF); 902 vp = nd.ni_vp; 903 if (fsflags & MNT_UPDATE) { 904 if ((vp->v_vflag & VV_ROOT) == 0) { 905 vput(vp); 906 return (EINVAL); 907 } 908 mp = vp->v_mount; 909 MNT_ILOCK(mp); 910 flag = mp->mnt_flag; 911 /* 912 * We only allow the filesystem to be reloaded if it 913 * is currently mounted read-only. 914 */ 915 if ((fsflags & MNT_RELOAD) && 916 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 917 MNT_IUNLOCK(mp); 918 vput(vp); 919 return (EOPNOTSUPP); /* Needs translation */ 920 } 921 MNT_IUNLOCK(mp); 922 /* 923 * Only privileged root, or (if MNT_USER is set) the user that 924 * did the original mount is permitted to update it. 925 */ 926 error = vfs_suser(mp, td); 927 if (error) { 928 vput(vp); 929 return (error); 930 } 931 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 932 vput(vp); 933 return (EBUSY); 934 } 935 VI_LOCK(vp); 936 if ((vp->v_iflag & VI_MOUNT) != 0 || 937 vp->v_mountedhere != NULL) { 938 VI_UNLOCK(vp); 939 vfs_unbusy(mp, td); 940 vput(vp); 941 return (EBUSY); 942 } 943 vp->v_iflag |= VI_MOUNT; 944 VI_UNLOCK(vp); 945 MNT_ILOCK(mp); 946 mp->mnt_flag |= fsflags & 947 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 948 MNT_IUNLOCK(mp); 949 VOP_UNLOCK(vp, 0, td); 950 mp->mnt_optnew = fsdata; 951 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 952 } else { 953 /* 954 * If the user is not root, ensure that they own the directory 955 * onto which we are attempting to mount. 956 */ 957 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 958 if (error) { 959 vput(vp); 960 return (error); 961 } 962 if (va.va_uid != td->td_ucred->cr_uid) { 963 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 964 0); 965 if (error) { 966 vput(vp); 967 return (error); 968 } 969 } 970 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 971 if (error != 0) { 972 vput(vp); 973 return (error); 974 } 975 if (vp->v_type != VDIR) { 976 vput(vp); 977 return (ENOTDIR); 978 } 979 VI_LOCK(vp); 980 if ((vp->v_iflag & VI_MOUNT) != 0 || 981 vp->v_mountedhere != NULL) { 982 VI_UNLOCK(vp); 983 vput(vp); 984 return (EBUSY); 985 } 986 vp->v_iflag |= VI_MOUNT; 987 VI_UNLOCK(vp); 988 989 /* 990 * Allocate and initialize the filesystem. 991 */ 992 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 993 VOP_UNLOCK(vp, 0, td); 994 995 /* XXXMAC: pass to vfs_mount_alloc? */ 996 mp->mnt_optnew = fsdata; 997 } 998 999 /* 1000 * Set the mount level flags. 1001 */ 1002 MNT_ILOCK(mp); 1003 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 1004 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 1005 MNT_RDONLY)); 1006 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1007 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1008 MNT_IUNLOCK(mp); 1009 /* 1010 * Mount the filesystem. 1011 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1012 * get. No freeing of cn_pnbuf. 1013 */ 1014 error = VFS_MOUNT(mp, td); 1015 1016 /* 1017 * Process the export option only if we are 1018 * updating mount options. 1019 */ 1020 if (!error && (fsflags & MNT_UPDATE)) { 1021 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1022 sizeof(export)) == 0) 1023 error = vfs_export(mp, &export); 1024 } 1025 1026 if (!error) { 1027 if (mp->mnt_opt != NULL) 1028 vfs_freeopts(mp->mnt_opt); 1029 mp->mnt_opt = mp->mnt_optnew; 1030 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 1031 } 1032 /* 1033 * Prevent external consumers of mount options from reading 1034 * mnt_optnew. 1035 */ 1036 mp->mnt_optnew = NULL; 1037 if (mp->mnt_flag & MNT_UPDATE) { 1038 MNT_ILOCK(mp); 1039 if (error) 1040 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1041 (flag & ~MNT_QUOTA); 1042 else 1043 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1044 MNT_FORCE | MNT_SNAPSHOT); 1045 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1046 mp->mnt_kern_flag |= MNTK_ASYNC; 1047 else 1048 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1049 MNT_IUNLOCK(mp); 1050 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1051 if (mp->mnt_syncer == NULL) 1052 error = vfs_allocate_syncvnode(mp); 1053 } else { 1054 if (mp->mnt_syncer != NULL) 1055 vrele(mp->mnt_syncer); 1056 mp->mnt_syncer = NULL; 1057 } 1058 vfs_unbusy(mp, td); 1059 VI_LOCK(vp); 1060 vp->v_iflag &= ~VI_MOUNT; 1061 VI_UNLOCK(vp); 1062 vrele(vp); 1063 return (error); 1064 } 1065 MNT_ILOCK(mp); 1066 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1067 mp->mnt_kern_flag |= MNTK_ASYNC; 1068 else 1069 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1070 MNT_IUNLOCK(mp); 1071 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 1072 /* 1073 * Put the new filesystem on the mount list after root. 1074 */ 1075 cache_purge(vp); 1076 if (!error) { 1077 struct vnode *newdp; 1078 1079 VI_LOCK(vp); 1080 vp->v_iflag &= ~VI_MOUNT; 1081 VI_UNLOCK(vp); 1082 vp->v_mountedhere = mp; 1083 mtx_lock(&mountlist_mtx); 1084 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1085 mtx_unlock(&mountlist_mtx); 1086 vfs_event_signal(NULL, VQ_MOUNT, 0); 1087 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 1088 panic("mount: lost mount"); 1089 mountcheckdirs(vp, newdp); 1090 vput(newdp); 1091 VOP_UNLOCK(vp, 0, td); 1092 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1093 error = vfs_allocate_syncvnode(mp); 1094 vfs_unbusy(mp, td); 1095 if (error) 1096 vrele(vp); 1097 } else { 1098 VI_LOCK(vp); 1099 vp->v_iflag &= ~VI_MOUNT; 1100 VI_UNLOCK(vp); 1101 vfs_unbusy(mp, td); 1102 vfs_mount_destroy(mp); 1103 vput(vp); 1104 } 1105 return (error); 1106 } 1107 1108 /* 1109 * Unmount a filesystem. 1110 * 1111 * Note: unmount takes a path to the vnode mounted on as argument, not 1112 * special file (as before). 1113 */ 1114 #ifndef _SYS_SYSPROTO_H_ 1115 struct unmount_args { 1116 char *path; 1117 int flags; 1118 }; 1119 #endif 1120 /* ARGSUSED */ 1121 int 1122 unmount(td, uap) 1123 struct thread *td; 1124 register struct unmount_args /* { 1125 char *path; 1126 int flags; 1127 } */ *uap; 1128 { 1129 struct mount *mp; 1130 char *pathbuf; 1131 int error, id0, id1; 1132 1133 if (jailed(td->td_ucred) || usermount == 0) { 1134 error = priv_check(td, PRIV_VFS_UNMOUNT); 1135 if (error) 1136 return (error); 1137 } 1138 1139 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1140 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1141 if (error) { 1142 free(pathbuf, M_TEMP); 1143 return (error); 1144 } 1145 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1); 1146 mtx_lock(&Giant); 1147 if (uap->flags & MNT_BYFSID) { 1148 /* Decode the filesystem ID. */ 1149 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1150 mtx_unlock(&Giant); 1151 free(pathbuf, M_TEMP); 1152 return (EINVAL); 1153 } 1154 1155 mtx_lock(&mountlist_mtx); 1156 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1157 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1158 mp->mnt_stat.f_fsid.val[1] == id1) 1159 break; 1160 } 1161 mtx_unlock(&mountlist_mtx); 1162 } else { 1163 mtx_lock(&mountlist_mtx); 1164 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1165 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1166 break; 1167 } 1168 mtx_unlock(&mountlist_mtx); 1169 } 1170 free(pathbuf, M_TEMP); 1171 if (mp == NULL) { 1172 /* 1173 * Previously we returned ENOENT for a nonexistent path and 1174 * EINVAL for a non-mountpoint. We cannot tell these apart 1175 * now, so in the !MNT_BYFSID case return the more likely 1176 * EINVAL for compatibility. 1177 */ 1178 mtx_unlock(&Giant); 1179 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1180 } 1181 1182 /* 1183 * Don't allow unmounting the root filesystem. 1184 */ 1185 if (mp->mnt_flag & MNT_ROOTFS) { 1186 mtx_unlock(&Giant); 1187 return (EINVAL); 1188 } 1189 error = dounmount(mp, uap->flags, td); 1190 mtx_unlock(&Giant); 1191 return (error); 1192 } 1193 1194 /* 1195 * Do the actual filesystem unmount. 1196 */ 1197 int 1198 dounmount(mp, flags, td) 1199 struct mount *mp; 1200 int flags; 1201 struct thread *td; 1202 { 1203 struct vnode *coveredvp, *fsrootvp; 1204 int error; 1205 int async_flag; 1206 int mnt_gen_r; 1207 1208 mtx_assert(&Giant, MA_OWNED); 1209 1210 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1211 mnt_gen_r = mp->mnt_gen; 1212 VI_LOCK(coveredvp); 1213 vholdl(coveredvp); 1214 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY, td); 1215 vdrop(coveredvp); 1216 /* 1217 * Check for mp being unmounted while waiting for the 1218 * covered vnode lock. 1219 */ 1220 if (coveredvp->v_mountedhere != mp || 1221 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1222 VOP_UNLOCK(coveredvp, 0, td); 1223 return (EBUSY); 1224 } 1225 } 1226 /* 1227 * Only privileged root, or (if MNT_USER is set) the user that did the 1228 * original mount is permitted to unmount this filesystem. 1229 */ 1230 error = vfs_suser(mp, td); 1231 if (error) { 1232 if (coveredvp) 1233 VOP_UNLOCK(coveredvp, 0, td); 1234 return (error); 1235 } 1236 1237 MNT_ILOCK(mp); 1238 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1239 MNT_IUNLOCK(mp); 1240 if (coveredvp) 1241 VOP_UNLOCK(coveredvp, 0, td); 1242 return (EBUSY); 1243 } 1244 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1245 /* Allow filesystems to detect that a forced unmount is in progress. */ 1246 if (flags & MNT_FORCE) 1247 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1248 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1249 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1250 if (error) { 1251 MNT_ILOCK(mp); 1252 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ | 1253 MNTK_UNMOUNTF); 1254 if (mp->mnt_kern_flag & MNTK_MWAIT) 1255 wakeup(mp); 1256 MNT_IUNLOCK(mp); 1257 if (coveredvp) 1258 VOP_UNLOCK(coveredvp, 0, td); 1259 return (error); 1260 } 1261 vn_start_write(NULL, &mp, V_WAIT); 1262 1263 if (mp->mnt_flag & MNT_EXPUBLIC) 1264 vfs_setpublicfs(NULL, NULL, NULL); 1265 1266 vfs_msync(mp, MNT_WAIT); 1267 MNT_ILOCK(mp); 1268 async_flag = mp->mnt_flag & MNT_ASYNC; 1269 mp->mnt_flag &= ~MNT_ASYNC; 1270 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1271 MNT_IUNLOCK(mp); 1272 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1273 if (mp->mnt_syncer != NULL) 1274 vrele(mp->mnt_syncer); 1275 /* 1276 * For forced unmounts, move process cdir/rdir refs on the fs root 1277 * vnode to the covered vnode. For non-forced unmounts we want 1278 * such references to cause an EBUSY error. 1279 */ 1280 if ((flags & MNT_FORCE) && 1281 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1282 if (mp->mnt_vnodecovered != NULL) 1283 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1284 if (fsrootvp == rootvnode) { 1285 vrele(rootvnode); 1286 rootvnode = NULL; 1287 } 1288 vput(fsrootvp); 1289 } 1290 if (((mp->mnt_flag & MNT_RDONLY) || 1291 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1292 (flags & MNT_FORCE)) { 1293 error = VFS_UNMOUNT(mp, flags, td); 1294 } 1295 vn_finished_write(mp); 1296 if (error) { 1297 /* Undo cdir/rdir and rootvnode changes made above. */ 1298 if ((flags & MNT_FORCE) && 1299 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1300 if (mp->mnt_vnodecovered != NULL) 1301 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1302 if (rootvnode == NULL) { 1303 rootvnode = fsrootvp; 1304 vref(rootvnode); 1305 } 1306 vput(fsrootvp); 1307 } 1308 MNT_ILOCK(mp); 1309 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1310 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1311 MNT_IUNLOCK(mp); 1312 (void) vfs_allocate_syncvnode(mp); 1313 MNT_ILOCK(mp); 1314 } 1315 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1316 mp->mnt_flag |= async_flag; 1317 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1318 mp->mnt_kern_flag |= MNTK_ASYNC; 1319 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1320 if (mp->mnt_kern_flag & MNTK_MWAIT) 1321 wakeup(mp); 1322 MNT_IUNLOCK(mp); 1323 if (coveredvp) 1324 VOP_UNLOCK(coveredvp, 0, td); 1325 return (error); 1326 } 1327 mtx_lock(&mountlist_mtx); 1328 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1329 mtx_unlock(&mountlist_mtx); 1330 if (coveredvp != NULL) { 1331 coveredvp->v_mountedhere = NULL; 1332 vput(coveredvp); 1333 } 1334 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1335 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1336 vfs_mount_destroy(mp); 1337 return (0); 1338 } 1339 1340 /* 1341 * --------------------------------------------------------------------- 1342 * Mounting of root filesystem 1343 * 1344 */ 1345 1346 struct root_hold_token { 1347 const char *who; 1348 LIST_ENTRY(root_hold_token) list; 1349 }; 1350 1351 static LIST_HEAD(, root_hold_token) root_holds = 1352 LIST_HEAD_INITIALIZER(&root_holds); 1353 1354 static int root_mount_complete; 1355 1356 /* 1357 * Hold root mount. 1358 */ 1359 struct root_hold_token * 1360 root_mount_hold(const char *identifier) 1361 { 1362 struct root_hold_token *h; 1363 1364 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1365 h->who = identifier; 1366 mtx_lock(&mountlist_mtx); 1367 LIST_INSERT_HEAD(&root_holds, h, list); 1368 mtx_unlock(&mountlist_mtx); 1369 return (h); 1370 } 1371 1372 /* 1373 * Release root mount. 1374 */ 1375 void 1376 root_mount_rel(struct root_hold_token *h) 1377 { 1378 1379 mtx_lock(&mountlist_mtx); 1380 LIST_REMOVE(h, list); 1381 wakeup(&root_holds); 1382 mtx_unlock(&mountlist_mtx); 1383 free(h, M_DEVBUF); 1384 } 1385 1386 /* 1387 * Wait for all subsystems to release root mount. 1388 */ 1389 static void 1390 root_mount_prepare(void) 1391 { 1392 struct root_hold_token *h; 1393 1394 for (;;) { 1395 DROP_GIANT(); 1396 g_waitidle(); 1397 PICKUP_GIANT(); 1398 mtx_lock(&mountlist_mtx); 1399 if (LIST_EMPTY(&root_holds)) { 1400 mtx_unlock(&mountlist_mtx); 1401 break; 1402 } 1403 printf("Root mount waiting for:"); 1404 LIST_FOREACH(h, &root_holds, list) 1405 printf(" %s", h->who); 1406 printf("\n"); 1407 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1408 hz); 1409 } 1410 } 1411 1412 /* 1413 * Root was mounted, share the good news. 1414 */ 1415 static void 1416 root_mount_done(void) 1417 { 1418 1419 /* 1420 * Use a mutex to prevent the wakeup being missed and waiting for 1421 * an extra 1 second sleep. 1422 */ 1423 mtx_lock(&mountlist_mtx); 1424 root_mount_complete = 1; 1425 wakeup(&root_mount_complete); 1426 mtx_unlock(&mountlist_mtx); 1427 } 1428 1429 /* 1430 * Return true if root is already mounted. 1431 */ 1432 int 1433 root_mounted(void) 1434 { 1435 1436 /* No mutex is acquired here because int stores are atomic. */ 1437 return (root_mount_complete); 1438 } 1439 1440 /* 1441 * Wait until root is mounted. 1442 */ 1443 void 1444 root_mount_wait(void) 1445 { 1446 1447 /* 1448 * Panic on an obvious deadlock - the function can't be called from 1449 * a thread which is doing the whole SYSINIT stuff. 1450 */ 1451 KASSERT(curthread->td_proc->p_pid != 0, 1452 ("root_mount_wait: cannot be called from the swapper thread")); 1453 mtx_lock(&mountlist_mtx); 1454 while (!root_mount_complete) { 1455 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1456 hz); 1457 } 1458 mtx_unlock(&mountlist_mtx); 1459 } 1460 1461 static void 1462 set_rootvnode(struct thread *td) 1463 { 1464 struct proc *p; 1465 1466 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1467 panic("Cannot find root vnode"); 1468 1469 p = td->td_proc; 1470 FILEDESC_SLOCK(p->p_fd); 1471 1472 if (p->p_fd->fd_cdir != NULL) 1473 vrele(p->p_fd->fd_cdir); 1474 p->p_fd->fd_cdir = rootvnode; 1475 VREF(rootvnode); 1476 1477 if (p->p_fd->fd_rdir != NULL) 1478 vrele(p->p_fd->fd_rdir); 1479 p->p_fd->fd_rdir = rootvnode; 1480 VREF(rootvnode); 1481 1482 FILEDESC_SUNLOCK(p->p_fd); 1483 1484 VOP_UNLOCK(rootvnode, 0, td); 1485 } 1486 1487 /* 1488 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1489 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1490 */ 1491 1492 static void 1493 devfs_first(void) 1494 { 1495 struct thread *td = curthread; 1496 struct vfsoptlist *opts; 1497 struct vfsconf *vfsp; 1498 struct mount *mp = NULL; 1499 int error; 1500 1501 vfsp = vfs_byname("devfs"); 1502 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1503 if (vfsp == NULL) 1504 return; 1505 1506 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1507 1508 error = VFS_MOUNT(mp, td); 1509 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1510 if (error) 1511 return; 1512 1513 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1514 TAILQ_INIT(opts); 1515 mp->mnt_opt = opts; 1516 1517 mtx_lock(&mountlist_mtx); 1518 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1519 mtx_unlock(&mountlist_mtx); 1520 1521 set_rootvnode(td); 1522 1523 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1524 if (error) 1525 printf("kern_symlink /dev -> / returns %d\n", error); 1526 } 1527 1528 /* 1529 * Surgically move our devfs to be mounted on /dev. 1530 */ 1531 1532 static void 1533 devfs_fixup(struct thread *td) 1534 { 1535 struct nameidata nd; 1536 int error; 1537 struct vnode *vp, *dvp; 1538 struct mount *mp; 1539 1540 /* Remove our devfs mount from the mountlist and purge the cache */ 1541 mtx_lock(&mountlist_mtx); 1542 mp = TAILQ_FIRST(&mountlist); 1543 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1544 mtx_unlock(&mountlist_mtx); 1545 cache_purgevfs(mp); 1546 1547 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1548 VI_LOCK(dvp); 1549 dvp->v_iflag &= ~VI_MOUNT; 1550 VI_UNLOCK(dvp); 1551 dvp->v_mountedhere = NULL; 1552 1553 /* Set up the real rootvnode, and purge the cache */ 1554 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1555 set_rootvnode(td); 1556 cache_purgevfs(rootvnode->v_mount); 1557 1558 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1559 error = namei(&nd); 1560 if (error) { 1561 printf("Lookup of /dev for devfs, error: %d\n", error); 1562 return; 1563 } 1564 NDFREE(&nd, NDF_ONLY_PNBUF); 1565 vp = nd.ni_vp; 1566 if (vp->v_type != VDIR) { 1567 vput(vp); 1568 } 1569 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1570 if (error) { 1571 vput(vp); 1572 } 1573 cache_purge(vp); 1574 mp->mnt_vnodecovered = vp; 1575 vp->v_mountedhere = mp; 1576 mtx_lock(&mountlist_mtx); 1577 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1578 mtx_unlock(&mountlist_mtx); 1579 VOP_UNLOCK(vp, 0, td); 1580 vput(dvp); 1581 vfs_unbusy(mp, td); 1582 1583 /* Unlink the no longer needed /dev/dev -> / symlink */ 1584 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1585 } 1586 1587 /* 1588 * Report errors during filesystem mounting. 1589 */ 1590 void 1591 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1592 { 1593 struct vfsoptlist *moptlist = mp->mnt_optnew; 1594 va_list ap; 1595 int error, len; 1596 char *errmsg; 1597 1598 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1599 if (error || errmsg == NULL || len <= 0) 1600 return; 1601 1602 va_start(ap, fmt); 1603 vsnprintf(errmsg, (size_t)len, fmt, ap); 1604 va_end(ap); 1605 } 1606 1607 /* 1608 * Find and mount the root filesystem 1609 */ 1610 void 1611 vfs_mountroot(void) 1612 { 1613 char *cp; 1614 int error, i, asked = 0; 1615 1616 root_mount_prepare(); 1617 1618 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1619 NULL, NULL, mount_init, mount_fini, 1620 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1621 devfs_first(); 1622 1623 /* 1624 * We are booted with instructions to prompt for the root filesystem. 1625 */ 1626 if (boothowto & RB_ASKNAME) { 1627 if (!vfs_mountroot_ask()) 1628 goto mounted; 1629 asked = 1; 1630 } 1631 1632 /* 1633 * The root filesystem information is compiled in, and we are 1634 * booted with instructions to use it. 1635 */ 1636 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1637 if (!vfs_mountroot_try(ctrootdevname)) 1638 goto mounted; 1639 ctrootdevname = NULL; 1640 } 1641 1642 /* 1643 * We've been given the generic "use CDROM as root" flag. This is 1644 * necessary because one media may be used in many different 1645 * devices, so we need to search for them. 1646 */ 1647 if (boothowto & RB_CDROM) { 1648 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1649 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1650 goto mounted; 1651 } 1652 } 1653 1654 /* 1655 * Try to use the value read by the loader from /etc/fstab, or 1656 * supplied via some other means. This is the preferred 1657 * mechanism. 1658 */ 1659 cp = getenv("vfs.root.mountfrom"); 1660 if (cp != NULL) { 1661 error = vfs_mountroot_try(cp); 1662 freeenv(cp); 1663 if (!error) 1664 goto mounted; 1665 } 1666 1667 /* 1668 * Try values that may have been computed by code during boot 1669 */ 1670 if (!vfs_mountroot_try(rootdevnames[0])) 1671 goto mounted; 1672 if (!vfs_mountroot_try(rootdevnames[1])) 1673 goto mounted; 1674 1675 /* 1676 * If we (still) have a compiled-in default, try it. 1677 */ 1678 if (ctrootdevname != NULL) 1679 if (!vfs_mountroot_try(ctrootdevname)) 1680 goto mounted; 1681 /* 1682 * Everything so far has failed, prompt on the console if we haven't 1683 * already tried that. 1684 */ 1685 if (!asked) 1686 if (!vfs_mountroot_ask()) 1687 goto mounted; 1688 1689 panic("Root mount failed, startup aborted."); 1690 1691 mounted: 1692 root_mount_done(); 1693 } 1694 1695 /* 1696 * Mount (mountfrom) as the root filesystem. 1697 */ 1698 static int 1699 vfs_mountroot_try(const char *mountfrom) 1700 { 1701 struct mount *mp; 1702 char *vfsname, *path; 1703 time_t timebase; 1704 int error; 1705 char patt[32]; 1706 1707 vfsname = NULL; 1708 path = NULL; 1709 mp = NULL; 1710 error = EINVAL; 1711 1712 if (mountfrom == NULL) 1713 return (error); /* don't complain */ 1714 printf("Trying to mount root from %s\n", mountfrom); 1715 1716 /* parse vfs name and path */ 1717 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1718 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1719 vfsname[0] = path[0] = 0; 1720 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1721 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1722 goto out; 1723 1724 if (path[0] == '\0') 1725 strcpy(path, ROOTNAME); 1726 1727 error = kernel_vmount( 1728 MNT_RDONLY | MNT_ROOTFS, 1729 "fstype", vfsname, 1730 "fspath", "/", 1731 "from", path, 1732 NULL); 1733 if (error == 0) { 1734 /* 1735 * We mount devfs prior to mounting the / FS, so the first 1736 * entry will typically be devfs. 1737 */ 1738 mp = TAILQ_FIRST(&mountlist); 1739 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1740 1741 /* 1742 * Iterate over all currently mounted file systems and use 1743 * the time stamp found to check and/or initialize the RTC. 1744 * Typically devfs has no time stamp and the only other FS 1745 * is the actual / FS. 1746 * Call inittodr() only once and pass it the largest of the 1747 * timestamps we encounter. 1748 */ 1749 timebase = 0; 1750 do { 1751 if (mp->mnt_time > timebase) 1752 timebase = mp->mnt_time; 1753 mp = TAILQ_NEXT(mp, mnt_list); 1754 } while (mp != NULL); 1755 inittodr(timebase); 1756 1757 devfs_fixup(curthread); 1758 } 1759 out: 1760 free(path, M_MOUNT); 1761 free(vfsname, M_MOUNT); 1762 return (error); 1763 } 1764 1765 /* 1766 * --------------------------------------------------------------------- 1767 * Interactive root filesystem selection code. 1768 */ 1769 1770 static int 1771 vfs_mountroot_ask(void) 1772 { 1773 char name[128]; 1774 1775 for(;;) { 1776 printf("\nManual root filesystem specification:\n"); 1777 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1778 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1779 printf(" eg. ufs:da0s1a\n"); 1780 #else 1781 printf(" eg. ufs:/dev/da0a\n"); 1782 #endif 1783 printf(" ? List valid disk boot devices\n"); 1784 printf(" <empty line> Abort manual input\n"); 1785 printf("\nmountroot> "); 1786 gets(name, sizeof(name), 1); 1787 if (name[0] == '\0') 1788 return (1); 1789 if (name[0] == '?') { 1790 printf("\nList of GEOM managed disk devices:\n "); 1791 g_dev_print(); 1792 continue; 1793 } 1794 if (!vfs_mountroot_try(name)) 1795 return (0); 1796 } 1797 } 1798 1799 /* 1800 * --------------------------------------------------------------------- 1801 * Functions for querying mount options/arguments from filesystems. 1802 */ 1803 1804 /* 1805 * Check that no unknown options are given 1806 */ 1807 int 1808 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1809 { 1810 struct vfsopt *opt; 1811 char errmsg[255]; 1812 const char **t, *p, *q; 1813 int ret = 0; 1814 1815 TAILQ_FOREACH(opt, opts, link) { 1816 p = opt->name; 1817 q = NULL; 1818 if (p[0] == 'n' && p[1] == 'o') 1819 q = p + 2; 1820 for(t = global_opts; *t != NULL; t++) { 1821 if (strcmp(*t, p) == 0) 1822 break; 1823 if (q != NULL) { 1824 if (strcmp(*t, q) == 0) 1825 break; 1826 } 1827 } 1828 if (*t != NULL) 1829 continue; 1830 for(t = legal; *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 snprintf(errmsg, sizeof(errmsg), 1841 "mount option <%s> is unknown", p); 1842 printf("%s\n", errmsg); 1843 ret = EINVAL; 1844 } 1845 if (ret != 0) { 1846 TAILQ_FOREACH(opt, opts, link) { 1847 if (strcmp(opt->name, "errmsg") == 0) { 1848 strncpy((char *)opt->value, errmsg, opt->len); 1849 } 1850 } 1851 } 1852 return (ret); 1853 } 1854 1855 /* 1856 * Get a mount option by its name. 1857 * 1858 * Return 0 if the option was found, ENOENT otherwise. 1859 * If len is non-NULL it will be filled with the length 1860 * of the option. If buf is non-NULL, it will be filled 1861 * with the address of the option. 1862 */ 1863 int 1864 vfs_getopt(opts, name, buf, len) 1865 struct vfsoptlist *opts; 1866 const char *name; 1867 void **buf; 1868 int *len; 1869 { 1870 struct vfsopt *opt; 1871 1872 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1873 1874 TAILQ_FOREACH(opt, opts, link) { 1875 if (strcmp(name, opt->name) == 0) { 1876 if (len != NULL) 1877 *len = opt->len; 1878 if (buf != NULL) 1879 *buf = opt->value; 1880 return (0); 1881 } 1882 } 1883 return (ENOENT); 1884 } 1885 1886 static int 1887 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1888 { 1889 struct vfsopt *opt; 1890 int i; 1891 1892 if (opts == NULL) 1893 return (-1); 1894 1895 i = 0; 1896 TAILQ_FOREACH(opt, opts, link) { 1897 if (strcmp(name, opt->name) == 0) 1898 return (i); 1899 ++i; 1900 } 1901 return (-1); 1902 } 1903 1904 char * 1905 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1906 { 1907 struct vfsopt *opt; 1908 1909 *error = 0; 1910 TAILQ_FOREACH(opt, opts, link) { 1911 if (strcmp(name, opt->name) != 0) 1912 continue; 1913 if (((char *)opt->value)[opt->len - 1] != '\0') { 1914 *error = EINVAL; 1915 return (NULL); 1916 } 1917 return (opt->value); 1918 } 1919 *error = ENOENT; 1920 return (NULL); 1921 } 1922 1923 int 1924 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1925 { 1926 struct vfsopt *opt; 1927 1928 TAILQ_FOREACH(opt, opts, link) { 1929 if (strcmp(name, opt->name) == 0) { 1930 if (w != NULL) 1931 *w |= val; 1932 return (1); 1933 } 1934 } 1935 if (w != NULL) 1936 *w &= ~val; 1937 return (0); 1938 } 1939 1940 int 1941 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1942 { 1943 va_list ap; 1944 struct vfsopt *opt; 1945 int ret; 1946 1947 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1948 1949 TAILQ_FOREACH(opt, opts, link) { 1950 if (strcmp(name, opt->name) != 0) 1951 continue; 1952 if (opt->len == 0 || opt->value == NULL) 1953 return (0); 1954 if (((char *)opt->value)[opt->len - 1] != '\0') 1955 return (0); 1956 va_start(ap, fmt); 1957 ret = vsscanf(opt->value, fmt, ap); 1958 va_end(ap); 1959 return (ret); 1960 } 1961 return (0); 1962 } 1963 1964 /* 1965 * Find and copy a mount option. 1966 * 1967 * The size of the buffer has to be specified 1968 * in len, if it is not the same length as the 1969 * mount option, EINVAL is returned. 1970 * Returns ENOENT if the option is not found. 1971 */ 1972 int 1973 vfs_copyopt(opts, name, dest, len) 1974 struct vfsoptlist *opts; 1975 const char *name; 1976 void *dest; 1977 int len; 1978 { 1979 struct vfsopt *opt; 1980 1981 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1982 1983 TAILQ_FOREACH(opt, opts, link) { 1984 if (strcmp(name, opt->name) == 0) { 1985 if (len != opt->len) 1986 return (EINVAL); 1987 bcopy(opt->value, dest, opt->len); 1988 return (0); 1989 } 1990 } 1991 return (ENOENT); 1992 } 1993 1994 /* 1995 * This is a helper function for filesystems to traverse their 1996 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1997 */ 1998 1999 struct vnode * 2000 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 2001 { 2002 struct vnode *vp; 2003 2004 mtx_assert(MNT_MTX(mp), MA_OWNED); 2005 2006 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2007 if ((*mvp)->v_yield++ == 500) { 2008 MNT_IUNLOCK(mp); 2009 (*mvp)->v_yield = 0; 2010 uio_yield(); 2011 MNT_ILOCK(mp); 2012 } 2013 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 2014 while (vp != NULL && vp->v_type == VMARKER) 2015 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2016 2017 /* Check if we are done */ 2018 if (vp == NULL) { 2019 __mnt_vnode_markerfree(mvp, mp); 2020 return (NULL); 2021 } 2022 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2023 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2024 return (vp); 2025 } 2026 2027 struct vnode * 2028 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2029 { 2030 struct vnode *vp; 2031 2032 mtx_assert(MNT_MTX(mp), MA_OWNED); 2033 2034 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2035 while (vp != NULL && vp->v_type == VMARKER) 2036 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2037 2038 /* Check if we are done */ 2039 if (vp == NULL) { 2040 *mvp = NULL; 2041 return (NULL); 2042 } 2043 mp->mnt_holdcnt++; 2044 MNT_IUNLOCK(mp); 2045 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2046 M_VNODE_MARKER, 2047 M_WAITOK | M_ZERO); 2048 MNT_ILOCK(mp); 2049 (*mvp)->v_type = VMARKER; 2050 2051 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2052 while (vp != NULL && vp->v_type == VMARKER) 2053 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2054 2055 /* Check if we are done */ 2056 if (vp == NULL) { 2057 MNT_IUNLOCK(mp); 2058 free(*mvp, M_VNODE_MARKER); 2059 MNT_ILOCK(mp); 2060 *mvp = NULL; 2061 mp->mnt_holdcnt--; 2062 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2063 wakeup(&mp->mnt_holdcnt); 2064 return (NULL); 2065 } 2066 mp->mnt_markercnt++; 2067 (*mvp)->v_mount = mp; 2068 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2069 return (vp); 2070 } 2071 2072 2073 void 2074 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2075 { 2076 2077 if (*mvp == NULL) 2078 return; 2079 2080 mtx_assert(MNT_MTX(mp), MA_OWNED); 2081 2082 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2083 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2084 MNT_IUNLOCK(mp); 2085 free(*mvp, M_VNODE_MARKER); 2086 MNT_ILOCK(mp); 2087 *mvp = NULL; 2088 2089 mp->mnt_markercnt--; 2090 mp->mnt_holdcnt--; 2091 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2092 wakeup(&mp->mnt_holdcnt); 2093 } 2094 2095 2096 int 2097 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 2098 { 2099 int error; 2100 2101 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 2102 if (sbp != &mp->mnt_stat) 2103 *sbp = mp->mnt_stat; 2104 return (error); 2105 } 2106 2107 void 2108 vfs_mountedfrom(struct mount *mp, const char *from) 2109 { 2110 2111 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2112 strlcpy(mp->mnt_stat.f_mntfromname, from, 2113 sizeof mp->mnt_stat.f_mntfromname); 2114 } 2115 2116 /* 2117 * --------------------------------------------------------------------- 2118 * This is the api for building mount args and mounting filesystems from 2119 * inside the kernel. 2120 * 2121 * The API works by accumulation of individual args. First error is 2122 * latched. 2123 * 2124 * XXX: should be documented in new manpage kernel_mount(9) 2125 */ 2126 2127 /* A memory allocation which must be freed when we are done */ 2128 struct mntaarg { 2129 SLIST_ENTRY(mntaarg) next; 2130 }; 2131 2132 /* The header for the mount arguments */ 2133 struct mntarg { 2134 struct iovec *v; 2135 int len; 2136 int error; 2137 SLIST_HEAD(, mntaarg) list; 2138 }; 2139 2140 /* 2141 * Add a boolean argument. 2142 * 2143 * flag is the boolean value. 2144 * name must start with "no". 2145 */ 2146 struct mntarg * 2147 mount_argb(struct mntarg *ma, int flag, const char *name) 2148 { 2149 2150 KASSERT(name[0] == 'n' && name[1] == 'o', 2151 ("mount_argb(...,%s): name must start with 'no'", name)); 2152 2153 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2154 } 2155 2156 /* 2157 * Add an argument printf style 2158 */ 2159 struct mntarg * 2160 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2161 { 2162 va_list ap; 2163 struct mntaarg *maa; 2164 struct sbuf *sb; 2165 int len; 2166 2167 if (ma == NULL) { 2168 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2169 SLIST_INIT(&ma->list); 2170 } 2171 if (ma->error) 2172 return (ma); 2173 2174 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2175 M_MOUNT, M_WAITOK); 2176 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2177 ma->v[ma->len].iov_len = strlen(name) + 1; 2178 ma->len++; 2179 2180 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 2181 va_start(ap, fmt); 2182 sbuf_vprintf(sb, fmt, ap); 2183 va_end(ap); 2184 sbuf_finish(sb); 2185 len = sbuf_len(sb) + 1; 2186 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2187 SLIST_INSERT_HEAD(&ma->list, maa, next); 2188 bcopy(sbuf_data(sb), maa + 1, len); 2189 sbuf_delete(sb); 2190 2191 ma->v[ma->len].iov_base = maa + 1; 2192 ma->v[ma->len].iov_len = len; 2193 ma->len++; 2194 2195 return (ma); 2196 } 2197 2198 /* 2199 * Add an argument which is a userland string. 2200 */ 2201 struct mntarg * 2202 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2203 { 2204 struct mntaarg *maa; 2205 char *tbuf; 2206 2207 if (val == NULL) 2208 return (ma); 2209 if (ma == NULL) { 2210 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2211 SLIST_INIT(&ma->list); 2212 } 2213 if (ma->error) 2214 return (ma); 2215 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2216 SLIST_INSERT_HEAD(&ma->list, maa, next); 2217 tbuf = (void *)(maa + 1); 2218 ma->error = copyinstr(val, tbuf, len, NULL); 2219 return (mount_arg(ma, name, tbuf, -1)); 2220 } 2221 2222 /* 2223 * Plain argument. 2224 * 2225 * If length is -1, use printf. 2226 */ 2227 struct mntarg * 2228 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2229 { 2230 2231 if (ma == NULL) { 2232 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2233 SLIST_INIT(&ma->list); 2234 } 2235 if (ma->error) 2236 return (ma); 2237 2238 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2239 M_MOUNT, M_WAITOK); 2240 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2241 ma->v[ma->len].iov_len = strlen(name) + 1; 2242 ma->len++; 2243 2244 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2245 if (len < 0) 2246 ma->v[ma->len].iov_len = strlen(val) + 1; 2247 else 2248 ma->v[ma->len].iov_len = len; 2249 ma->len++; 2250 return (ma); 2251 } 2252 2253 /* 2254 * Free a mntarg structure 2255 */ 2256 static void 2257 free_mntarg(struct mntarg *ma) 2258 { 2259 struct mntaarg *maa; 2260 2261 while (!SLIST_EMPTY(&ma->list)) { 2262 maa = SLIST_FIRST(&ma->list); 2263 SLIST_REMOVE_HEAD(&ma->list, next); 2264 free(maa, M_MOUNT); 2265 } 2266 free(ma->v, M_MOUNT); 2267 free(ma, M_MOUNT); 2268 } 2269 2270 /* 2271 * Mount a filesystem 2272 */ 2273 int 2274 kernel_mount(struct mntarg *ma, int flags) 2275 { 2276 struct uio auio; 2277 int error; 2278 2279 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2280 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2281 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2282 2283 auio.uio_iov = ma->v; 2284 auio.uio_iovcnt = ma->len; 2285 auio.uio_segflg = UIO_SYSSPACE; 2286 2287 error = ma->error; 2288 if (!error) 2289 error = vfs_donmount(curthread, flags, &auio); 2290 free_mntarg(ma); 2291 return (error); 2292 } 2293 2294 /* 2295 * A printflike function to mount a filesystem. 2296 */ 2297 int 2298 kernel_vmount(int flags, ...) 2299 { 2300 struct mntarg *ma = NULL; 2301 va_list ap; 2302 const char *cp; 2303 const void *vp; 2304 int error; 2305 2306 va_start(ap, flags); 2307 for (;;) { 2308 cp = va_arg(ap, const char *); 2309 if (cp == NULL) 2310 break; 2311 vp = va_arg(ap, const void *); 2312 ma = mount_arg(ma, cp, vp, -1); 2313 } 2314 va_end(ap); 2315 2316 error = kernel_mount(ma, flags); 2317 return (error); 2318 }
Cache object: 36e5fe63eec8e86e93c1c681f9c10b11
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