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 int vfs_donmount(struct thread *td, int fsflags, 86 struct uio *fsoptions); 87 static void free_mntarg(struct mntarg *ma); 88 static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name); 89 90 static int usermount = 0; 91 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 92 "Unprivileged users may mount and unmount file systems"); 93 94 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 95 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 96 static uma_zone_t mount_zone; 97 98 /* List of mounted filesystems. */ 99 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 100 101 /* For any iteration/modification of mountlist */ 102 struct mtx mountlist_mtx; 103 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 104 105 TAILQ_HEAD(vfsoptlist, vfsopt); 106 struct vfsopt { 107 TAILQ_ENTRY(vfsopt) link; 108 char *name; 109 void *value; 110 int len; 111 }; 112 113 /* 114 * The vnode of the system's root (/ in the filesystem, without chroot 115 * active.) 116 */ 117 struct vnode *rootvnode; 118 119 /* 120 * The root filesystem is detailed in the kernel environment variable 121 * vfs.root.mountfrom, which is expected to be in the general format 122 * 123 * <vfsname>:[<path>] 124 * vfsname := the name of a VFS known to the kernel and capable 125 * of being mounted as root 126 * path := disk device name or other data used by the filesystem 127 * to locate its physical store 128 */ 129 130 /* 131 * Global opts, taken by all filesystems 132 */ 133 static const char *global_opts[] = { 134 "errmsg", 135 "fstype", 136 "fspath", 137 "ro", 138 "rw", 139 "nosuid", 140 "noexec", 141 "update", 142 NULL 143 }; 144 145 /* 146 * The root specifiers we will try if RB_CDROM is specified. 147 */ 148 static char *cdrom_rootdevnames[] = { 149 "cd9660:cd0", 150 "cd9660:acd0", 151 NULL 152 }; 153 154 /* legacy find-root code */ 155 char *rootdevnames[2] = {NULL, NULL}; 156 #ifndef ROOTDEVNAME 157 # define ROOTDEVNAME NULL 158 #endif 159 static const char *ctrootdevname = ROOTDEVNAME; 160 161 /* 162 * --------------------------------------------------------------------- 163 * Functions for building and sanitizing the mount options 164 */ 165 166 /* Remove one mount option. */ 167 static void 168 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 169 { 170 171 TAILQ_REMOVE(opts, opt, link); 172 free(opt->name, M_MOUNT); 173 if (opt->value != NULL) 174 free(opt->value, M_MOUNT); 175 #ifdef INVARIANTS 176 else if (opt->len != 0) 177 panic("%s: mount option with NULL value but length != 0", 178 __func__); 179 #endif 180 free(opt, M_MOUNT); 181 } 182 183 /* Release all resources related to the mount options. */ 184 void 185 vfs_freeopts(struct vfsoptlist *opts) 186 { 187 struct vfsopt *opt; 188 189 while (!TAILQ_EMPTY(opts)) { 190 opt = TAILQ_FIRST(opts); 191 vfs_freeopt(opts, opt); 192 } 193 free(opts, M_MOUNT); 194 } 195 196 void 197 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 198 { 199 struct vfsopt *opt, *temp; 200 201 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 202 if (strcmp(opt->name, name) == 0) 203 vfs_freeopt(opts, opt); 204 } 205 } 206 207 /* 208 * Check if options are equal (with or without the "no" prefix). 209 */ 210 static int 211 vfs_equalopts(const char *opt1, const char *opt2) 212 { 213 214 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 215 if (strcmp(opt1, opt2) == 0) 216 return (1); 217 /* "noopt" vs. "opt" */ 218 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 219 return (1); 220 /* "opt" vs. "noopt" */ 221 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 222 return (1); 223 return (0); 224 } 225 226 /* 227 * If a mount option is specified several times, 228 * (with or without the "no" prefix) only keep 229 * the last occurence of it. 230 */ 231 static void 232 vfs_sanitizeopts(struct vfsoptlist *opts) 233 { 234 struct vfsopt *opt, *opt2, *tmp; 235 236 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 237 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 238 while (opt2 != NULL) { 239 if (vfs_equalopts(opt->name, opt2->name)) { 240 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 241 vfs_freeopt(opts, opt2); 242 opt2 = tmp; 243 } else { 244 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 245 } 246 } 247 } 248 } 249 250 /* 251 * Build a linked list of mount options from a struct uio. 252 */ 253 static int 254 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 255 { 256 struct vfsoptlist *opts; 257 struct vfsopt *opt; 258 size_t memused; 259 unsigned int i, iovcnt; 260 int error, namelen, optlen; 261 262 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 263 TAILQ_INIT(opts); 264 memused = 0; 265 iovcnt = auio->uio_iovcnt; 266 for (i = 0; i < iovcnt; i += 2) { 267 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 268 namelen = auio->uio_iov[i].iov_len; 269 optlen = auio->uio_iov[i + 1].iov_len; 270 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 271 opt->value = NULL; 272 opt->len = 0; 273 274 /* 275 * Do this early, so jumps to "bad" will free the current 276 * option. 277 */ 278 TAILQ_INSERT_TAIL(opts, opt, link); 279 memused += sizeof(struct vfsopt) + optlen + namelen; 280 281 /* 282 * Avoid consuming too much memory, and attempts to overflow 283 * memused. 284 */ 285 if (memused > VFS_MOUNTARG_SIZE_MAX || 286 optlen > VFS_MOUNTARG_SIZE_MAX || 287 namelen > VFS_MOUNTARG_SIZE_MAX) { 288 error = EINVAL; 289 goto bad; 290 } 291 292 if (auio->uio_segflg == UIO_SYSSPACE) { 293 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 294 } else { 295 error = copyin(auio->uio_iov[i].iov_base, opt->name, 296 namelen); 297 if (error) 298 goto bad; 299 } 300 /* Ensure names are null-terminated strings. */ 301 if (opt->name[namelen - 1] != '\0') { 302 error = EINVAL; 303 goto bad; 304 } 305 if (optlen != 0) { 306 opt->len = optlen; 307 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 308 if (auio->uio_segflg == UIO_SYSSPACE) { 309 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 310 optlen); 311 } else { 312 error = copyin(auio->uio_iov[i + 1].iov_base, 313 opt->value, optlen); 314 if (error) 315 goto bad; 316 } 317 } 318 } 319 vfs_sanitizeopts(opts); 320 *options = opts; 321 return (0); 322 bad: 323 vfs_freeopts(opts); 324 return (error); 325 } 326 327 /* 328 * Merge the old mount options with the new ones passed 329 * in the MNT_UPDATE case. 330 */ 331 static void 332 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts) 333 { 334 struct vfsopt *opt, *opt2, *new; 335 336 TAILQ_FOREACH(opt, opts, link) { 337 /* 338 * Check that this option hasn't been redefined 339 * nor cancelled with a "no" mount option. 340 */ 341 opt2 = TAILQ_FIRST(toopts); 342 while (opt2 != NULL) { 343 if (strcmp(opt2->name, opt->name) == 0) 344 goto next; 345 if (strncmp(opt2->name, "no", 2) == 0 && 346 strcmp(opt2->name + 2, opt->name) == 0) { 347 vfs_freeopt(toopts, opt2); 348 goto next; 349 } 350 opt2 = TAILQ_NEXT(opt2, link); 351 } 352 /* We want this option, duplicate it. */ 353 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 354 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK); 355 strcpy(new->name, opt->name); 356 if (opt->len != 0) { 357 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 358 bcopy(opt->value, new->value, opt->len); 359 } else { 360 new->value = NULL; 361 } 362 new->len = opt->len; 363 TAILQ_INSERT_TAIL(toopts, new, link); 364 next: 365 continue; 366 } 367 } 368 369 /* 370 * Mount a filesystem. 371 */ 372 int 373 nmount(td, uap) 374 struct thread *td; 375 struct nmount_args /* { 376 struct iovec *iovp; 377 unsigned int iovcnt; 378 int flags; 379 } */ *uap; 380 { 381 struct uio *auio; 382 struct iovec *iov; 383 unsigned int i; 384 int error; 385 u_int iovcnt; 386 387 AUDIT_ARG(fflags, uap->flags); 388 389 /* 390 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 391 * userspace to set this flag, but we must filter it out if we want 392 * MNT_UPDATE on the root file system to work. 393 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 394 */ 395 uap->flags &= ~MNT_ROOTFS; 396 397 iovcnt = uap->iovcnt; 398 /* 399 * Check that we have an even number of iovec's 400 * and that we have at least two options. 401 */ 402 if ((iovcnt & 1) || (iovcnt < 4)) 403 return (EINVAL); 404 405 error = copyinuio(uap->iovp, iovcnt, &auio); 406 if (error) 407 return (error); 408 iov = auio->uio_iov; 409 for (i = 0; i < iovcnt; i++) { 410 if (iov->iov_len > MMAXOPTIONLEN) { 411 free(auio, M_IOV); 412 return (EINVAL); 413 } 414 iov++; 415 } 416 error = vfs_donmount(td, uap->flags, auio); 417 418 free(auio, M_IOV); 419 return (error); 420 } 421 422 /* 423 * --------------------------------------------------------------------- 424 * Various utility functions 425 */ 426 427 void 428 vfs_ref(struct mount *mp) 429 { 430 431 MNT_ILOCK(mp); 432 MNT_REF(mp); 433 MNT_IUNLOCK(mp); 434 } 435 436 void 437 vfs_rel(struct mount *mp) 438 { 439 440 MNT_ILOCK(mp); 441 MNT_REL(mp); 442 MNT_IUNLOCK(mp); 443 } 444 445 static int 446 mount_init(void *mem, int size, int flags) 447 { 448 struct mount *mp; 449 450 mp = (struct mount *)mem; 451 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 452 lockinit(&mp->mnt_lock, PVFS, "vfslock", 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_lock); 463 mtx_destroy(&mp->mnt_mtx); 464 } 465 466 /* 467 * Allocate and initialize the mount point struct. 468 */ 469 struct mount * 470 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, 471 const char *fspath, struct thread *td) 472 { 473 struct mount *mp; 474 475 mp = uma_zalloc(mount_zone, M_WAITOK); 476 bzero(&mp->mnt_startzero, 477 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 478 TAILQ_INIT(&mp->mnt_nvnodelist); 479 mp->mnt_nvnodelistsize = 0; 480 mp->mnt_ref = 0; 481 (void) vfs_busy(mp, LK_NOWAIT, 0, td); 482 mp->mnt_op = vfsp->vfc_vfsops; 483 mp->mnt_vfc = vfsp; 484 vfsp->vfc_refcount++; /* XXX Unlocked */ 485 mp->mnt_stat.f_type = vfsp->vfc_typenum; 486 mp->mnt_gen++; 487 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 488 mp->mnt_vnodecovered = vp; 489 mp->mnt_cred = crdup(td->td_ucred); 490 mp->mnt_stat.f_owner = td->td_ucred->cr_uid; 491 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 492 mp->mnt_iosize_max = DFLTPHYS; 493 #ifdef MAC 494 mac_init_mount(mp); 495 mac_create_mount(td->td_ucred, mp); 496 #endif 497 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 498 return (mp); 499 } 500 501 /* 502 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 503 */ 504 void 505 vfs_mount_destroy(struct mount *mp) 506 { 507 int i; 508 509 MNT_ILOCK(mp); 510 for (i = 0; mp->mnt_ref && i < 3; i++) 511 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz); 512 /* 513 * This will always cause a 3 second delay in rebooting due to 514 * refs on the root mountpoint that never go away. Most of these 515 * are held by init which never exits. 516 */ 517 if (i == 3 && (!rebooting || bootverbose)) 518 printf("Mount point %s had %d dangling refs\n", 519 mp->mnt_stat.f_mntonname, mp->mnt_ref); 520 if (mp->mnt_holdcnt != 0) { 521 printf("Waiting for mount point to be unheld\n"); 522 while (mp->mnt_holdcnt != 0) { 523 mp->mnt_holdcntwaiters++; 524 msleep(&mp->mnt_holdcnt, MNT_MTX(mp), 525 PZERO, "mntdestroy", 0); 526 mp->mnt_holdcntwaiters--; 527 } 528 printf("mount point unheld\n"); 529 } 530 if (mp->mnt_writeopcount > 0) { 531 printf("Waiting for mount point write ops\n"); 532 while (mp->mnt_writeopcount > 0) { 533 mp->mnt_kern_flag |= MNTK_SUSPEND; 534 msleep(&mp->mnt_writeopcount, 535 MNT_MTX(mp), 536 PZERO, "mntdestroy2", 0); 537 } 538 printf("mount point write ops completed\n"); 539 } 540 if (mp->mnt_secondary_writes > 0) { 541 printf("Waiting for mount point secondary write ops\n"); 542 while (mp->mnt_secondary_writes > 0) { 543 mp->mnt_kern_flag |= MNTK_SUSPEND; 544 msleep(&mp->mnt_secondary_writes, 545 MNT_MTX(mp), 546 PZERO, "mntdestroy3", 0); 547 } 548 printf("mount point secondary write ops completed\n"); 549 } 550 MNT_IUNLOCK(mp); 551 mp->mnt_vfc->vfc_refcount--; 552 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 553 struct vnode *vp; 554 555 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 556 vprint("", vp); 557 panic("unmount: dangling vnode"); 558 } 559 MNT_ILOCK(mp); 560 if (mp->mnt_kern_flag & MNTK_MWAIT) 561 wakeup(mp); 562 if (mp->mnt_writeopcount != 0) 563 panic("vfs_mount_destroy: nonzero writeopcount"); 564 if (mp->mnt_secondary_writes != 0) 565 panic("vfs_mount_destroy: nonzero secondary_writes"); 566 if (mp->mnt_nvnodelistsize != 0) 567 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 568 mp->mnt_writeopcount = -1000; 569 mp->mnt_nvnodelistsize = -1000; 570 mp->mnt_secondary_writes = -1000; 571 MNT_IUNLOCK(mp); 572 #ifdef MAC 573 mac_destroy_mount(mp); 574 #endif 575 if (mp->mnt_opt != NULL) 576 vfs_freeopts(mp->mnt_opt); 577 crfree(mp->mnt_cred); 578 uma_zfree(mount_zone, mp); 579 } 580 581 static int 582 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions) 583 { 584 struct vfsoptlist *optlist; 585 struct vfsopt *opt, *noro_opt; 586 char *fstype, *fspath, *errmsg; 587 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 588 int has_rw, has_noro; 589 590 errmsg = NULL; 591 errmsg_len = 0; 592 errmsg_pos = -1; 593 has_rw = 0; 594 has_noro = 0; 595 596 error = vfs_buildopts(fsoptions, &optlist); 597 if (error) 598 return (error); 599 600 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 601 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 602 603 /* 604 * We need these two options before the others, 605 * and they are mandatory for any filesystem. 606 * Ensure they are NUL terminated as well. 607 */ 608 fstypelen = 0; 609 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 610 if (error || fstype[fstypelen - 1] != '\0') { 611 error = EINVAL; 612 if (errmsg != NULL) 613 strncpy(errmsg, "Invalid fstype", errmsg_len); 614 goto bail; 615 } 616 fspathlen = 0; 617 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 618 if (error || fspath[fspathlen - 1] != '\0') { 619 error = EINVAL; 620 if (errmsg != NULL) 621 strncpy(errmsg, "Invalid fspath", errmsg_len); 622 goto bail; 623 } 624 625 /* 626 * We need to see if we have the "update" option 627 * before we call vfs_domount(), since vfs_domount() has special 628 * logic based on MNT_UPDATE. This is very important 629 * when we want to update the root filesystem. 630 */ 631 TAILQ_FOREACH(opt, optlist, link) { 632 if (strcmp(opt->name, "update") == 0) 633 fsflags |= MNT_UPDATE; 634 else if (strcmp(opt->name, "async") == 0) 635 fsflags |= MNT_ASYNC; 636 else if (strcmp(opt->name, "force") == 0) 637 fsflags |= MNT_FORCE; 638 else if (strcmp(opt->name, "multilabel") == 0) 639 fsflags |= MNT_MULTILABEL; 640 else if (strcmp(opt->name, "noasync") == 0) 641 fsflags &= ~MNT_ASYNC; 642 else if (strcmp(opt->name, "noatime") == 0) 643 fsflags |= MNT_NOATIME; 644 else if (strcmp(opt->name, "atime") == 0) { 645 free(opt->name, M_MOUNT); 646 opt->name = strdup("nonoatime", M_MOUNT); 647 } 648 else if (strcmp(opt->name, "noclusterr") == 0) 649 fsflags |= MNT_NOCLUSTERR; 650 else if (strcmp(opt->name, "clusterr") == 0) { 651 free(opt->name, M_MOUNT); 652 opt->name = strdup("nonoclusterr", M_MOUNT); 653 } 654 else if (strcmp(opt->name, "noclusterw") == 0) 655 fsflags |= MNT_NOCLUSTERW; 656 else if (strcmp(opt->name, "clusterw") == 0) { 657 free(opt->name, M_MOUNT); 658 opt->name = strdup("nonoclusterw", M_MOUNT); 659 } 660 else if (strcmp(opt->name, "noexec") == 0) 661 fsflags |= MNT_NOEXEC; 662 else if (strcmp(opt->name, "exec") == 0) { 663 free(opt->name, M_MOUNT); 664 opt->name = strdup("nonoexec", M_MOUNT); 665 } 666 else if (strcmp(opt->name, "nosuid") == 0) 667 fsflags |= MNT_NOSUID; 668 else if (strcmp(opt->name, "suid") == 0) { 669 free(opt->name, M_MOUNT); 670 opt->name = strdup("nonosuid", M_MOUNT); 671 } 672 else if (strcmp(opt->name, "nosymfollow") == 0) 673 fsflags |= MNT_NOSYMFOLLOW; 674 else if (strcmp(opt->name, "symfollow") == 0) { 675 free(opt->name, M_MOUNT); 676 opt->name = strdup("nonosymfollow", M_MOUNT); 677 } 678 else if (strcmp(opt->name, "noro") == 0) { 679 fsflags &= ~MNT_RDONLY; 680 has_noro = 1; 681 } 682 else if (strcmp(opt->name, "rw") == 0) { 683 fsflags &= ~MNT_RDONLY; 684 has_rw = 1; 685 } 686 else if (strcmp(opt->name, "ro") == 0) 687 fsflags |= MNT_RDONLY; 688 else if (strcmp(opt->name, "rdonly") == 0) { 689 free(opt->name, M_MOUNT); 690 opt->name = strdup("ro", M_MOUNT); 691 fsflags |= MNT_RDONLY; 692 } 693 else if (strcmp(opt->name, "snapshot") == 0) 694 fsflags |= MNT_SNAPSHOT; 695 else if (strcmp(opt->name, "suiddir") == 0) 696 fsflags |= MNT_SUIDDIR; 697 else if (strcmp(opt->name, "sync") == 0) 698 fsflags |= MNT_SYNCHRONOUS; 699 else if (strcmp(opt->name, "union") == 0) 700 fsflags |= MNT_UNION; 701 } 702 703 /* 704 * If "rw" was specified as a mount option, and we 705 * are trying to update a mount-point from "ro" to "rw", 706 * we need a mount option "noro", since in vfs_mergeopts(), 707 * "noro" will cancel "ro", but "rw" will not do anything. 708 */ 709 if (has_rw && !has_noro) { 710 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 711 noro_opt->name = strdup("noro", M_MOUNT); 712 noro_opt->value = NULL; 713 noro_opt->len = 0; 714 TAILQ_INSERT_TAIL(optlist, noro_opt, link); 715 } 716 717 /* 718 * Be ultra-paranoid about making sure the type and fspath 719 * variables will fit in our mp buffers, including the 720 * terminating NUL. 721 */ 722 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 723 error = ENAMETOOLONG; 724 goto bail; 725 } 726 727 mtx_lock(&Giant); 728 error = vfs_domount(td, fstype, fspath, fsflags, optlist); 729 mtx_unlock(&Giant); 730 bail: 731 /* copyout the errmsg */ 732 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 733 && errmsg_len > 0 && errmsg != NULL) { 734 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 735 bcopy(errmsg, 736 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 737 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 738 } else { 739 copyout(errmsg, 740 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 741 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 742 } 743 } 744 745 if (error != 0) 746 vfs_freeopts(optlist); 747 return (error); 748 } 749 750 /* 751 * Old mount API. 752 */ 753 #ifndef _SYS_SYSPROTO_H_ 754 struct mount_args { 755 char *type; 756 char *path; 757 int flags; 758 caddr_t data; 759 }; 760 #endif 761 /* ARGSUSED */ 762 int 763 mount(td, uap) 764 struct thread *td; 765 struct mount_args /* { 766 char *type; 767 char *path; 768 int flags; 769 caddr_t data; 770 } */ *uap; 771 { 772 char *fstype; 773 struct vfsconf *vfsp = NULL; 774 struct mntarg *ma = NULL; 775 int error; 776 777 AUDIT_ARG(fflags, uap->flags); 778 779 /* 780 * Filter out MNT_ROOTFS. We do not want clients of mount() in 781 * userspace to set this flag, but we must filter it out if we want 782 * MNT_UPDATE on the root file system to work. 783 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try(). 784 */ 785 uap->flags &= ~MNT_ROOTFS; 786 787 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 788 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 789 if (error) { 790 free(fstype, M_TEMP); 791 return (error); 792 } 793 794 AUDIT_ARG(text, fstype); 795 mtx_lock(&Giant); 796 vfsp = vfs_byname_kld(fstype, td, &error); 797 free(fstype, M_TEMP); 798 if (vfsp == NULL) { 799 mtx_unlock(&Giant); 800 return (ENOENT); 801 } 802 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 803 mtx_unlock(&Giant); 804 return (EOPNOTSUPP); 805 } 806 807 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 808 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 809 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro"); 810 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid"); 811 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec"); 812 813 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td); 814 mtx_unlock(&Giant); 815 return (error); 816 } 817 818 819 /* 820 * vfs_domount(): actually attempt a filesystem mount. 821 */ 822 static int 823 vfs_domount( 824 struct thread *td, /* Calling thread. */ 825 const char *fstype, /* Filesystem type. */ 826 char *fspath, /* Mount path. */ 827 int fsflags, /* Flags common to all filesystems. */ 828 void *fsdata /* Options local to the filesystem. */ 829 ) 830 { 831 struct vnode *vp; 832 struct mount *mp; 833 struct vfsconf *vfsp; 834 struct export_args export; 835 int error, flag = 0; 836 struct vattr va; 837 struct nameidata nd; 838 839 mtx_assert(&Giant, MA_OWNED); 840 /* 841 * Be ultra-paranoid about making sure the type and fspath 842 * variables will fit in our mp buffers, including the 843 * terminating NUL. 844 */ 845 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 846 return (ENAMETOOLONG); 847 848 if (jailed(td->td_ucred) || usermount == 0) { 849 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 850 return (error); 851 } 852 853 /* 854 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 855 */ 856 if (fsflags & MNT_EXPORTED) { 857 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 858 if (error) 859 return (error); 860 } 861 if (fsflags & MNT_SUIDDIR) { 862 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 863 if (error) 864 return (error); 865 } 866 /* 867 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 868 */ 869 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 870 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 871 fsflags |= MNT_NOSUID | MNT_USER; 872 } 873 874 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 875 vfsp = NULL; 876 if ((fsflags & MNT_UPDATE) == 0) { 877 /* Don't try to load KLDs if we're mounting the root. */ 878 if (fsflags & MNT_ROOTFS) 879 vfsp = vfs_byname(fstype); 880 else 881 vfsp = vfs_byname_kld(fstype, td, &error); 882 if (vfsp == NULL) 883 return (ENODEV); 884 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 885 return (EPERM); 886 } 887 /* 888 * Get vnode to be covered 889 */ 890 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE, 891 fspath, td); 892 if ((error = namei(&nd)) != 0) 893 return (error); 894 NDFREE(&nd, NDF_ONLY_PNBUF); 895 vp = nd.ni_vp; 896 if (fsflags & MNT_UPDATE) { 897 if ((vp->v_vflag & VV_ROOT) == 0) { 898 vput(vp); 899 return (EINVAL); 900 } 901 mp = vp->v_mount; 902 MNT_ILOCK(mp); 903 flag = mp->mnt_flag; 904 /* 905 * We only allow the filesystem to be reloaded if it 906 * is currently mounted read-only. 907 */ 908 if ((fsflags & MNT_RELOAD) && 909 ((mp->mnt_flag & MNT_RDONLY) == 0)) { 910 MNT_IUNLOCK(mp); 911 vput(vp); 912 return (EOPNOTSUPP); /* Needs translation */ 913 } 914 MNT_IUNLOCK(mp); 915 /* 916 * Only privileged root, or (if MNT_USER is set) the user that 917 * did the original mount is permitted to update it. 918 */ 919 error = vfs_suser(mp, td); 920 if (error) { 921 vput(vp); 922 return (error); 923 } 924 if (vfs_busy(mp, LK_NOWAIT, 0, td)) { 925 vput(vp); 926 return (EBUSY); 927 } 928 VI_LOCK(vp); 929 if ((vp->v_iflag & VI_MOUNT) != 0 || 930 vp->v_mountedhere != NULL) { 931 VI_UNLOCK(vp); 932 vfs_unbusy(mp, td); 933 vput(vp); 934 return (EBUSY); 935 } 936 vp->v_iflag |= VI_MOUNT; 937 VI_UNLOCK(vp); 938 MNT_ILOCK(mp); 939 mp->mnt_flag |= fsflags & 940 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS); 941 MNT_IUNLOCK(mp); 942 VOP_UNLOCK(vp, 0, td); 943 mp->mnt_optnew = fsdata; 944 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 945 } else { 946 /* 947 * If the user is not root, ensure that they own the directory 948 * onto which we are attempting to mount. 949 */ 950 error = VOP_GETATTR(vp, &va, td->td_ucred, td); 951 if (error) { 952 vput(vp); 953 return (error); 954 } 955 if (va.va_uid != td->td_ucred->cr_uid) { 956 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 957 0); 958 if (error) { 959 vput(vp); 960 return (error); 961 } 962 } 963 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 964 if (error != 0) { 965 vput(vp); 966 return (error); 967 } 968 if (vp->v_type != VDIR) { 969 vput(vp); 970 return (ENOTDIR); 971 } 972 VI_LOCK(vp); 973 if ((vp->v_iflag & VI_MOUNT) != 0 || 974 vp->v_mountedhere != NULL) { 975 VI_UNLOCK(vp); 976 vput(vp); 977 return (EBUSY); 978 } 979 vp->v_iflag |= VI_MOUNT; 980 VI_UNLOCK(vp); 981 982 /* 983 * Allocate and initialize the filesystem. 984 */ 985 mp = vfs_mount_alloc(vp, vfsp, fspath, td); 986 VOP_UNLOCK(vp, 0, td); 987 988 /* XXXMAC: pass to vfs_mount_alloc? */ 989 mp->mnt_optnew = fsdata; 990 } 991 992 /* 993 * Set the mount level flags. 994 */ 995 MNT_ILOCK(mp); 996 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) | 997 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS | 998 MNT_RDONLY)); 999 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1000 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1001 MNT_IUNLOCK(mp); 1002 /* 1003 * Mount the filesystem. 1004 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1005 * get. No freeing of cn_pnbuf. 1006 */ 1007 error = VFS_MOUNT(mp, td); 1008 1009 /* 1010 * Process the export option only if we are 1011 * updating mount options. 1012 */ 1013 if (!error && (fsflags & MNT_UPDATE)) { 1014 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 1015 sizeof(export)) == 0) 1016 error = vfs_export(mp, &export); 1017 } 1018 1019 if (!error) { 1020 if (mp->mnt_opt != NULL) 1021 vfs_freeopts(mp->mnt_opt); 1022 mp->mnt_opt = mp->mnt_optnew; 1023 (void)VFS_STATFS(mp, &mp->mnt_stat, td); 1024 } 1025 /* 1026 * Prevent external consumers of mount options from reading 1027 * mnt_optnew. 1028 */ 1029 mp->mnt_optnew = NULL; 1030 if (mp->mnt_flag & MNT_UPDATE) { 1031 MNT_ILOCK(mp); 1032 if (error) 1033 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | 1034 (flag & ~MNT_QUOTA); 1035 else 1036 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | 1037 MNT_FORCE | MNT_SNAPSHOT); 1038 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1039 mp->mnt_kern_flag |= MNTK_ASYNC; 1040 else 1041 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1042 MNT_IUNLOCK(mp); 1043 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1044 if (mp->mnt_syncer == NULL) 1045 error = vfs_allocate_syncvnode(mp); 1046 } else { 1047 if (mp->mnt_syncer != NULL) 1048 vrele(mp->mnt_syncer); 1049 mp->mnt_syncer = NULL; 1050 } 1051 vfs_unbusy(mp, td); 1052 VI_LOCK(vp); 1053 vp->v_iflag &= ~VI_MOUNT; 1054 VI_UNLOCK(vp); 1055 vrele(vp); 1056 return (error); 1057 } 1058 MNT_ILOCK(mp); 1059 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1060 mp->mnt_kern_flag |= MNTK_ASYNC; 1061 else 1062 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1063 MNT_IUNLOCK(mp); 1064 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 1065 /* 1066 * Put the new filesystem on the mount list after root. 1067 */ 1068 cache_purge(vp); 1069 if (!error) { 1070 struct vnode *newdp; 1071 1072 VI_LOCK(vp); 1073 vp->v_iflag &= ~VI_MOUNT; 1074 VI_UNLOCK(vp); 1075 vp->v_mountedhere = mp; 1076 mtx_lock(&mountlist_mtx); 1077 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1078 mtx_unlock(&mountlist_mtx); 1079 vfs_event_signal(NULL, VQ_MOUNT, 0); 1080 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td)) 1081 panic("mount: lost mount"); 1082 mountcheckdirs(vp, newdp); 1083 vput(newdp); 1084 VOP_UNLOCK(vp, 0, td); 1085 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1086 error = vfs_allocate_syncvnode(mp); 1087 vfs_unbusy(mp, td); 1088 if (error) 1089 vrele(vp); 1090 } else { 1091 VI_LOCK(vp); 1092 vp->v_iflag &= ~VI_MOUNT; 1093 VI_UNLOCK(vp); 1094 vfs_unbusy(mp, td); 1095 vfs_mount_destroy(mp); 1096 vput(vp); 1097 } 1098 return (error); 1099 } 1100 1101 /* 1102 * Unmount a filesystem. 1103 * 1104 * Note: unmount takes a path to the vnode mounted on as argument, not 1105 * special file (as before). 1106 */ 1107 #ifndef _SYS_SYSPROTO_H_ 1108 struct unmount_args { 1109 char *path; 1110 int flags; 1111 }; 1112 #endif 1113 /* ARGSUSED */ 1114 int 1115 unmount(td, uap) 1116 struct thread *td; 1117 register struct unmount_args /* { 1118 char *path; 1119 int flags; 1120 } */ *uap; 1121 { 1122 struct mount *mp; 1123 char *pathbuf; 1124 int error, id0, id1; 1125 1126 if (jailed(td->td_ucred) || usermount == 0) { 1127 error = priv_check(td, PRIV_VFS_UNMOUNT); 1128 if (error) 1129 return (error); 1130 } 1131 1132 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1133 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1134 if (error) { 1135 free(pathbuf, M_TEMP); 1136 return (error); 1137 } 1138 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1); 1139 mtx_lock(&Giant); 1140 if (uap->flags & MNT_BYFSID) { 1141 /* Decode the filesystem ID. */ 1142 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1143 mtx_unlock(&Giant); 1144 free(pathbuf, M_TEMP); 1145 return (EINVAL); 1146 } 1147 1148 mtx_lock(&mountlist_mtx); 1149 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1150 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1151 mp->mnt_stat.f_fsid.val[1] == id1) 1152 break; 1153 } 1154 mtx_unlock(&mountlist_mtx); 1155 } else { 1156 mtx_lock(&mountlist_mtx); 1157 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1158 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1159 break; 1160 } 1161 mtx_unlock(&mountlist_mtx); 1162 } 1163 free(pathbuf, M_TEMP); 1164 if (mp == NULL) { 1165 /* 1166 * Previously we returned ENOENT for a nonexistent path and 1167 * EINVAL for a non-mountpoint. We cannot tell these apart 1168 * now, so in the !MNT_BYFSID case return the more likely 1169 * EINVAL for compatibility. 1170 */ 1171 mtx_unlock(&Giant); 1172 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1173 } 1174 1175 /* 1176 * Don't allow unmounting the root filesystem. 1177 */ 1178 if (mp->mnt_flag & MNT_ROOTFS) { 1179 mtx_unlock(&Giant); 1180 return (EINVAL); 1181 } 1182 error = dounmount(mp, uap->flags, td); 1183 mtx_unlock(&Giant); 1184 return (error); 1185 } 1186 1187 /* 1188 * Do the actual filesystem unmount. 1189 */ 1190 int 1191 dounmount(mp, flags, td) 1192 struct mount *mp; 1193 int flags; 1194 struct thread *td; 1195 { 1196 struct vnode *coveredvp, *fsrootvp; 1197 int error; 1198 int async_flag; 1199 int mnt_gen_r; 1200 1201 mtx_assert(&Giant, MA_OWNED); 1202 1203 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1204 mnt_gen_r = mp->mnt_gen; 1205 VI_LOCK(coveredvp); 1206 vholdl(coveredvp); 1207 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY, td); 1208 vdrop(coveredvp); 1209 /* 1210 * Check for mp being unmounted while waiting for the 1211 * covered vnode lock. 1212 */ 1213 if (coveredvp->v_mountedhere != mp || 1214 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1215 VOP_UNLOCK(coveredvp, 0, td); 1216 return (EBUSY); 1217 } 1218 } 1219 /* 1220 * Only privileged root, or (if MNT_USER is set) the user that did the 1221 * original mount is permitted to unmount this filesystem. 1222 */ 1223 error = vfs_suser(mp, td); 1224 if (error) { 1225 if (coveredvp) 1226 VOP_UNLOCK(coveredvp, 0, td); 1227 return (error); 1228 } 1229 1230 MNT_ILOCK(mp); 1231 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 1232 MNT_IUNLOCK(mp); 1233 if (coveredvp) 1234 VOP_UNLOCK(coveredvp, 0, td); 1235 return (EBUSY); 1236 } 1237 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1238 /* Allow filesystems to detect that a forced unmount is in progress. */ 1239 if (flags & MNT_FORCE) 1240 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1241 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK | 1242 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td); 1243 if (error) { 1244 MNT_ILOCK(mp); 1245 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ | 1246 MNTK_UNMOUNTF); 1247 if (mp->mnt_kern_flag & MNTK_MWAIT) 1248 wakeup(mp); 1249 MNT_IUNLOCK(mp); 1250 if (coveredvp) 1251 VOP_UNLOCK(coveredvp, 0, td); 1252 return (error); 1253 } 1254 vn_start_write(NULL, &mp, V_WAIT); 1255 1256 if (mp->mnt_flag & MNT_EXPUBLIC) 1257 vfs_setpublicfs(NULL, NULL, NULL); 1258 1259 vfs_msync(mp, MNT_WAIT); 1260 MNT_ILOCK(mp); 1261 async_flag = mp->mnt_flag & MNT_ASYNC; 1262 mp->mnt_flag &= ~MNT_ASYNC; 1263 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1264 MNT_IUNLOCK(mp); 1265 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1266 if (mp->mnt_syncer != NULL) 1267 vrele(mp->mnt_syncer); 1268 /* 1269 * For forced unmounts, move process cdir/rdir refs on the fs root 1270 * vnode to the covered vnode. For non-forced unmounts we want 1271 * such references to cause an EBUSY error. 1272 */ 1273 if ((flags & MNT_FORCE) && 1274 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1275 if (mp->mnt_vnodecovered != NULL) 1276 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1277 if (fsrootvp == rootvnode) { 1278 vrele(rootvnode); 1279 rootvnode = NULL; 1280 } 1281 vput(fsrootvp); 1282 } 1283 if (((mp->mnt_flag & MNT_RDONLY) || 1284 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) || 1285 (flags & MNT_FORCE)) { 1286 error = VFS_UNMOUNT(mp, flags, td); 1287 } 1288 vn_finished_write(mp); 1289 if (error) { 1290 /* Undo cdir/rdir and rootvnode changes made above. */ 1291 if ((flags & MNT_FORCE) && 1292 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) { 1293 if (mp->mnt_vnodecovered != NULL) 1294 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1295 if (rootvnode == NULL) { 1296 rootvnode = fsrootvp; 1297 vref(rootvnode); 1298 } 1299 vput(fsrootvp); 1300 } 1301 MNT_ILOCK(mp); 1302 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1303 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) { 1304 MNT_IUNLOCK(mp); 1305 (void) vfs_allocate_syncvnode(mp); 1306 MNT_ILOCK(mp); 1307 } 1308 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1309 mp->mnt_flag |= async_flag; 1310 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 1311 mp->mnt_kern_flag |= MNTK_ASYNC; 1312 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1313 if (mp->mnt_kern_flag & MNTK_MWAIT) 1314 wakeup(mp); 1315 MNT_IUNLOCK(mp); 1316 if (coveredvp) 1317 VOP_UNLOCK(coveredvp, 0, td); 1318 return (error); 1319 } 1320 mtx_lock(&mountlist_mtx); 1321 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1322 mtx_unlock(&mountlist_mtx); 1323 if (coveredvp != NULL) { 1324 coveredvp->v_mountedhere = NULL; 1325 vput(coveredvp); 1326 } 1327 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1328 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); 1329 vfs_mount_destroy(mp); 1330 return (0); 1331 } 1332 1333 /* 1334 * --------------------------------------------------------------------- 1335 * Mounting of root filesystem 1336 * 1337 */ 1338 1339 struct root_hold_token { 1340 const char *who; 1341 LIST_ENTRY(root_hold_token) list; 1342 }; 1343 1344 static LIST_HEAD(, root_hold_token) root_holds = 1345 LIST_HEAD_INITIALIZER(&root_holds); 1346 1347 static int root_mount_complete; 1348 1349 /* 1350 * Hold root mount. 1351 */ 1352 struct root_hold_token * 1353 root_mount_hold(const char *identifier) 1354 { 1355 struct root_hold_token *h; 1356 1357 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK); 1358 h->who = identifier; 1359 mtx_lock(&mountlist_mtx); 1360 LIST_INSERT_HEAD(&root_holds, h, list); 1361 mtx_unlock(&mountlist_mtx); 1362 return (h); 1363 } 1364 1365 /* 1366 * Release root mount. 1367 */ 1368 void 1369 root_mount_rel(struct root_hold_token *h) 1370 { 1371 1372 mtx_lock(&mountlist_mtx); 1373 LIST_REMOVE(h, list); 1374 wakeup(&root_holds); 1375 mtx_unlock(&mountlist_mtx); 1376 free(h, M_DEVBUF); 1377 } 1378 1379 /* 1380 * Wait for all subsystems to release root mount. 1381 */ 1382 static void 1383 root_mount_prepare(void) 1384 { 1385 struct root_hold_token *h; 1386 1387 for (;;) { 1388 DROP_GIANT(); 1389 g_waitidle(); 1390 PICKUP_GIANT(); 1391 mtx_lock(&mountlist_mtx); 1392 if (LIST_EMPTY(&root_holds)) { 1393 mtx_unlock(&mountlist_mtx); 1394 break; 1395 } 1396 printf("Root mount waiting for:"); 1397 LIST_FOREACH(h, &root_holds, list) 1398 printf(" %s", h->who); 1399 printf("\n"); 1400 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold", 1401 hz); 1402 } 1403 } 1404 1405 /* 1406 * Root was mounted, share the good news. 1407 */ 1408 static void 1409 root_mount_done(void) 1410 { 1411 1412 /* 1413 * Use a mutex to prevent the wakeup being missed and waiting for 1414 * an extra 1 second sleep. 1415 */ 1416 mtx_lock(&mountlist_mtx); 1417 root_mount_complete = 1; 1418 wakeup(&root_mount_complete); 1419 mtx_unlock(&mountlist_mtx); 1420 } 1421 1422 /* 1423 * Return true if root is already mounted. 1424 */ 1425 int 1426 root_mounted(void) 1427 { 1428 1429 /* No mutex is acquired here because int stores are atomic. */ 1430 return (root_mount_complete); 1431 } 1432 1433 /* 1434 * Wait until root is mounted. 1435 */ 1436 void 1437 root_mount_wait(void) 1438 { 1439 1440 /* 1441 * Panic on an obvious deadlock - the function can't be called from 1442 * a thread which is doing the whole SYSINIT stuff. 1443 */ 1444 KASSERT(curthread->td_proc->p_pid != 0, 1445 ("root_mount_wait: cannot be called from the swapper thread")); 1446 mtx_lock(&mountlist_mtx); 1447 while (!root_mount_complete) { 1448 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait", 1449 hz); 1450 } 1451 mtx_unlock(&mountlist_mtx); 1452 } 1453 1454 static void 1455 set_rootvnode(struct thread *td) 1456 { 1457 struct proc *p; 1458 1459 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td)) 1460 panic("Cannot find root vnode"); 1461 1462 p = td->td_proc; 1463 FILEDESC_SLOCK(p->p_fd); 1464 1465 if (p->p_fd->fd_cdir != NULL) 1466 vrele(p->p_fd->fd_cdir); 1467 p->p_fd->fd_cdir = rootvnode; 1468 VREF(rootvnode); 1469 1470 if (p->p_fd->fd_rdir != NULL) 1471 vrele(p->p_fd->fd_rdir); 1472 p->p_fd->fd_rdir = rootvnode; 1473 VREF(rootvnode); 1474 1475 FILEDESC_SUNLOCK(p->p_fd); 1476 1477 VOP_UNLOCK(rootvnode, 0, td); 1478 } 1479 1480 /* 1481 * Mount /devfs as our root filesystem, but do not put it on the mountlist 1482 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup. 1483 */ 1484 1485 static void 1486 devfs_first(void) 1487 { 1488 struct thread *td = curthread; 1489 struct vfsoptlist *opts; 1490 struct vfsconf *vfsp; 1491 struct mount *mp = NULL; 1492 int error; 1493 1494 vfsp = vfs_byname("devfs"); 1495 KASSERT(vfsp != NULL, ("Could not find devfs by name")); 1496 if (vfsp == NULL) 1497 return; 1498 1499 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td); 1500 1501 error = VFS_MOUNT(mp, td); 1502 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error)); 1503 if (error) 1504 return; 1505 1506 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 1507 TAILQ_INIT(opts); 1508 mp->mnt_opt = opts; 1509 1510 mtx_lock(&mountlist_mtx); 1511 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list); 1512 mtx_unlock(&mountlist_mtx); 1513 1514 set_rootvnode(td); 1515 1516 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE); 1517 if (error) 1518 printf("kern_symlink /dev -> / returns %d\n", error); 1519 } 1520 1521 /* 1522 * Surgically move our devfs to be mounted on /dev. 1523 */ 1524 1525 static void 1526 devfs_fixup(struct thread *td) 1527 { 1528 struct nameidata nd; 1529 int error; 1530 struct vnode *vp, *dvp; 1531 struct mount *mp; 1532 1533 /* Remove our devfs mount from the mountlist and purge the cache */ 1534 mtx_lock(&mountlist_mtx); 1535 mp = TAILQ_FIRST(&mountlist); 1536 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1537 mtx_unlock(&mountlist_mtx); 1538 cache_purgevfs(mp); 1539 1540 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td); 1541 VI_LOCK(dvp); 1542 dvp->v_iflag &= ~VI_MOUNT; 1543 VI_UNLOCK(dvp); 1544 dvp->v_mountedhere = NULL; 1545 1546 /* Set up the real rootvnode, and purge the cache */ 1547 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL; 1548 set_rootvnode(td); 1549 cache_purgevfs(rootvnode->v_mount); 1550 1551 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td); 1552 error = namei(&nd); 1553 if (error) { 1554 printf("Lookup of /dev for devfs, error: %d\n", error); 1555 return; 1556 } 1557 NDFREE(&nd, NDF_ONLY_PNBUF); 1558 vp = nd.ni_vp; 1559 if (vp->v_type != VDIR) { 1560 vput(vp); 1561 } 1562 error = vinvalbuf(vp, V_SAVE, td, 0, 0); 1563 if (error) { 1564 vput(vp); 1565 } 1566 cache_purge(vp); 1567 mp->mnt_vnodecovered = vp; 1568 vp->v_mountedhere = mp; 1569 mtx_lock(&mountlist_mtx); 1570 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1571 mtx_unlock(&mountlist_mtx); 1572 VOP_UNLOCK(vp, 0, td); 1573 vput(dvp); 1574 vfs_unbusy(mp, td); 1575 1576 /* Unlink the no longer needed /dev/dev -> / symlink */ 1577 kern_unlink(td, "/dev/dev", UIO_SYSSPACE); 1578 } 1579 1580 /* 1581 * Report errors during filesystem mounting. 1582 */ 1583 void 1584 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1585 { 1586 struct vfsoptlist *moptlist = mp->mnt_optnew; 1587 va_list ap; 1588 int error, len; 1589 char *errmsg; 1590 1591 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1592 if (error || errmsg == NULL || len <= 0) 1593 return; 1594 1595 va_start(ap, fmt); 1596 vsnprintf(errmsg, (size_t)len, fmt, ap); 1597 va_end(ap); 1598 } 1599 1600 /* 1601 * Find and mount the root filesystem 1602 */ 1603 void 1604 vfs_mountroot(void) 1605 { 1606 char *cp; 1607 int error, i, asked = 0; 1608 1609 root_mount_prepare(); 1610 1611 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), 1612 NULL, NULL, mount_init, mount_fini, 1613 UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 1614 devfs_first(); 1615 1616 /* 1617 * We are booted with instructions to prompt for the root filesystem. 1618 */ 1619 if (boothowto & RB_ASKNAME) { 1620 if (!vfs_mountroot_ask()) 1621 goto mounted; 1622 asked = 1; 1623 } 1624 1625 /* 1626 * The root filesystem information is compiled in, and we are 1627 * booted with instructions to use it. 1628 */ 1629 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) { 1630 if (!vfs_mountroot_try(ctrootdevname)) 1631 goto mounted; 1632 ctrootdevname = NULL; 1633 } 1634 1635 /* 1636 * We've been given the generic "use CDROM as root" flag. This is 1637 * necessary because one media may be used in many different 1638 * devices, so we need to search for them. 1639 */ 1640 if (boothowto & RB_CDROM) { 1641 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) { 1642 if (!vfs_mountroot_try(cdrom_rootdevnames[i])) 1643 goto mounted; 1644 } 1645 } 1646 1647 /* 1648 * Try to use the value read by the loader from /etc/fstab, or 1649 * supplied via some other means. This is the preferred 1650 * mechanism. 1651 */ 1652 cp = getenv("vfs.root.mountfrom"); 1653 if (cp != NULL) { 1654 error = vfs_mountroot_try(cp); 1655 freeenv(cp); 1656 if (!error) 1657 goto mounted; 1658 } 1659 1660 /* 1661 * Try values that may have been computed by code during boot 1662 */ 1663 if (!vfs_mountroot_try(rootdevnames[0])) 1664 goto mounted; 1665 if (!vfs_mountroot_try(rootdevnames[1])) 1666 goto mounted; 1667 1668 /* 1669 * If we (still) have a compiled-in default, try it. 1670 */ 1671 if (ctrootdevname != NULL) 1672 if (!vfs_mountroot_try(ctrootdevname)) 1673 goto mounted; 1674 /* 1675 * Everything so far has failed, prompt on the console if we haven't 1676 * already tried that. 1677 */ 1678 if (!asked) 1679 if (!vfs_mountroot_ask()) 1680 goto mounted; 1681 1682 panic("Root mount failed, startup aborted."); 1683 1684 mounted: 1685 root_mount_done(); 1686 } 1687 1688 /* 1689 * Mount (mountfrom) as the root filesystem. 1690 */ 1691 static int 1692 vfs_mountroot_try(const char *mountfrom) 1693 { 1694 struct mount *mp; 1695 char *vfsname, *path; 1696 time_t timebase; 1697 int error; 1698 char patt[32]; 1699 1700 vfsname = NULL; 1701 path = NULL; 1702 mp = NULL; 1703 error = EINVAL; 1704 1705 if (mountfrom == NULL) 1706 return (error); /* don't complain */ 1707 printf("Trying to mount root from %s\n", mountfrom); 1708 1709 /* parse vfs name and path */ 1710 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK); 1711 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK); 1712 vfsname[0] = path[0] = 0; 1713 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN); 1714 if (sscanf(mountfrom, patt, vfsname, path) < 1) 1715 goto out; 1716 1717 if (path[0] == '\0') 1718 strcpy(path, ROOTNAME); 1719 1720 error = kernel_vmount( 1721 MNT_RDONLY | MNT_ROOTFS, 1722 "fstype", vfsname, 1723 "fspath", "/", 1724 "from", path, 1725 NULL); 1726 if (error == 0) { 1727 /* 1728 * We mount devfs prior to mounting the / FS, so the first 1729 * entry will typically be devfs. 1730 */ 1731 mp = TAILQ_FIRST(&mountlist); 1732 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__)); 1733 1734 /* 1735 * Iterate over all currently mounted file systems and use 1736 * the time stamp found to check and/or initialize the RTC. 1737 * Typically devfs has no time stamp and the only other FS 1738 * is the actual / FS. 1739 * Call inittodr() only once and pass it the largest of the 1740 * timestamps we encounter. 1741 */ 1742 timebase = 0; 1743 do { 1744 if (mp->mnt_time > timebase) 1745 timebase = mp->mnt_time; 1746 mp = TAILQ_NEXT(mp, mnt_list); 1747 } while (mp != NULL); 1748 inittodr(timebase); 1749 1750 devfs_fixup(curthread); 1751 } 1752 out: 1753 free(path, M_MOUNT); 1754 free(vfsname, M_MOUNT); 1755 return (error); 1756 } 1757 1758 /* 1759 * --------------------------------------------------------------------- 1760 * Interactive root filesystem selection code. 1761 */ 1762 1763 static int 1764 vfs_mountroot_ask(void) 1765 { 1766 char name[128]; 1767 1768 for(;;) { 1769 printf("\nManual root filesystem specification:\n"); 1770 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n"); 1771 #if defined(__amd64__) || defined(__i386__) || defined(__ia64__) 1772 printf(" eg. ufs:da0s1a\n"); 1773 #else 1774 printf(" eg. ufs:/dev/da0a\n"); 1775 #endif 1776 printf(" ? List valid disk boot devices\n"); 1777 printf(" <empty line> Abort manual input\n"); 1778 printf("\nmountroot> "); 1779 gets(name, sizeof(name), 1); 1780 if (name[0] == '\0') 1781 return (1); 1782 if (name[0] == '?') { 1783 printf("\nList of GEOM managed disk devices:\n "); 1784 g_dev_print(); 1785 continue; 1786 } 1787 if (!vfs_mountroot_try(name)) 1788 return (0); 1789 } 1790 } 1791 1792 /* 1793 * --------------------------------------------------------------------- 1794 * Functions for querying mount options/arguments from filesystems. 1795 */ 1796 1797 /* 1798 * Check that no unknown options are given 1799 */ 1800 int 1801 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1802 { 1803 struct vfsopt *opt; 1804 char errmsg[255]; 1805 const char **t, *p, *q; 1806 int ret = 0; 1807 1808 TAILQ_FOREACH(opt, opts, link) { 1809 p = opt->name; 1810 q = NULL; 1811 if (p[0] == 'n' && p[1] == 'o') 1812 q = p + 2; 1813 for(t = global_opts; *t != NULL; t++) { 1814 if (strcmp(*t, p) == 0) 1815 break; 1816 if (q != NULL) { 1817 if (strcmp(*t, q) == 0) 1818 break; 1819 } 1820 } 1821 if (*t != NULL) 1822 continue; 1823 for(t = legal; *t != NULL; t++) { 1824 if (strcmp(*t, p) == 0) 1825 break; 1826 if (q != NULL) { 1827 if (strcmp(*t, q) == 0) 1828 break; 1829 } 1830 } 1831 if (*t != NULL) 1832 continue; 1833 snprintf(errmsg, sizeof(errmsg), 1834 "mount option <%s> is unknown", p); 1835 printf("%s\n", errmsg); 1836 ret = EINVAL; 1837 } 1838 if (ret != 0) { 1839 TAILQ_FOREACH(opt, opts, link) { 1840 if (strcmp(opt->name, "errmsg") == 0) { 1841 strncpy((char *)opt->value, errmsg, opt->len); 1842 } 1843 } 1844 } 1845 return (ret); 1846 } 1847 1848 /* 1849 * Get a mount option by its name. 1850 * 1851 * Return 0 if the option was found, ENOENT otherwise. 1852 * If len is non-NULL it will be filled with the length 1853 * of the option. If buf is non-NULL, it will be filled 1854 * with the address of the option. 1855 */ 1856 int 1857 vfs_getopt(opts, name, buf, len) 1858 struct vfsoptlist *opts; 1859 const char *name; 1860 void **buf; 1861 int *len; 1862 { 1863 struct vfsopt *opt; 1864 1865 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1866 1867 TAILQ_FOREACH(opt, opts, link) { 1868 if (strcmp(name, opt->name) == 0) { 1869 if (len != NULL) 1870 *len = opt->len; 1871 if (buf != NULL) 1872 *buf = opt->value; 1873 return (0); 1874 } 1875 } 1876 return (ENOENT); 1877 } 1878 1879 static int 1880 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1881 { 1882 struct vfsopt *opt; 1883 int i; 1884 1885 if (opts == NULL) 1886 return (-1); 1887 1888 i = 0; 1889 TAILQ_FOREACH(opt, opts, link) { 1890 if (strcmp(name, opt->name) == 0) 1891 return (i); 1892 ++i; 1893 } 1894 return (-1); 1895 } 1896 1897 char * 1898 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1899 { 1900 struct vfsopt *opt; 1901 1902 *error = 0; 1903 TAILQ_FOREACH(opt, opts, link) { 1904 if (strcmp(name, opt->name) != 0) 1905 continue; 1906 if (((char *)opt->value)[opt->len - 1] != '\0') { 1907 *error = EINVAL; 1908 return (NULL); 1909 } 1910 return (opt->value); 1911 } 1912 *error = ENOENT; 1913 return (NULL); 1914 } 1915 1916 int 1917 vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val) 1918 { 1919 struct vfsopt *opt; 1920 1921 TAILQ_FOREACH(opt, opts, link) { 1922 if (strcmp(name, opt->name) == 0) { 1923 if (w != NULL) 1924 *w |= val; 1925 return (1); 1926 } 1927 } 1928 if (w != NULL) 1929 *w &= ~val; 1930 return (0); 1931 } 1932 1933 int 1934 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1935 { 1936 va_list ap; 1937 struct vfsopt *opt; 1938 int ret; 1939 1940 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1941 1942 TAILQ_FOREACH(opt, opts, link) { 1943 if (strcmp(name, opt->name) != 0) 1944 continue; 1945 if (opt->len == 0 || opt->value == NULL) 1946 return (0); 1947 if (((char *)opt->value)[opt->len - 1] != '\0') 1948 return (0); 1949 va_start(ap, fmt); 1950 ret = vsscanf(opt->value, fmt, ap); 1951 va_end(ap); 1952 return (ret); 1953 } 1954 return (0); 1955 } 1956 1957 /* 1958 * Find and copy a mount option. 1959 * 1960 * The size of the buffer has to be specified 1961 * in len, if it is not the same length as the 1962 * mount option, EINVAL is returned. 1963 * Returns ENOENT if the option is not found. 1964 */ 1965 int 1966 vfs_copyopt(opts, name, dest, len) 1967 struct vfsoptlist *opts; 1968 const char *name; 1969 void *dest; 1970 int len; 1971 { 1972 struct vfsopt *opt; 1973 1974 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1975 1976 TAILQ_FOREACH(opt, opts, link) { 1977 if (strcmp(name, opt->name) == 0) { 1978 if (len != opt->len) 1979 return (EINVAL); 1980 bcopy(opt->value, dest, opt->len); 1981 return (0); 1982 } 1983 } 1984 return (ENOENT); 1985 } 1986 1987 /* 1988 * This is a helper function for filesystems to traverse their 1989 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h 1990 */ 1991 1992 struct vnode * 1993 __mnt_vnode_next(struct vnode **mvp, struct mount *mp) 1994 { 1995 struct vnode *vp; 1996 1997 mtx_assert(MNT_MTX(mp), MA_OWNED); 1998 1999 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2000 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 2001 while (vp != NULL && vp->v_type == VMARKER) 2002 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2003 2004 /* Check if we are done */ 2005 if (vp == NULL) { 2006 __mnt_vnode_markerfree(mvp, mp); 2007 return (NULL); 2008 } 2009 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2010 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2011 return (vp); 2012 } 2013 2014 struct vnode * 2015 __mnt_vnode_first(struct vnode **mvp, struct mount *mp) 2016 { 2017 struct vnode *vp; 2018 2019 mtx_assert(MNT_MTX(mp), MA_OWNED); 2020 2021 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2022 while (vp != NULL && vp->v_type == VMARKER) 2023 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2024 2025 /* Check if we are done */ 2026 if (vp == NULL) { 2027 *mvp = NULL; 2028 return (NULL); 2029 } 2030 mp->mnt_holdcnt++; 2031 MNT_IUNLOCK(mp); 2032 *mvp = (struct vnode *) malloc(sizeof(struct vnode), 2033 M_VNODE_MARKER, 2034 M_WAITOK | M_ZERO); 2035 MNT_ILOCK(mp); 2036 (*mvp)->v_type = VMARKER; 2037 2038 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 2039 while (vp != NULL && vp->v_type == VMARKER) 2040 vp = TAILQ_NEXT(vp, v_nmntvnodes); 2041 2042 /* Check if we are done */ 2043 if (vp == NULL) { 2044 MNT_IUNLOCK(mp); 2045 free(*mvp, M_VNODE_MARKER); 2046 MNT_ILOCK(mp); 2047 *mvp = NULL; 2048 mp->mnt_holdcnt--; 2049 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2050 wakeup(&mp->mnt_holdcnt); 2051 return (NULL); 2052 } 2053 mp->mnt_markercnt++; 2054 (*mvp)->v_mount = mp; 2055 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 2056 return (vp); 2057 } 2058 2059 2060 void 2061 __mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp) 2062 { 2063 2064 if (*mvp == NULL) 2065 return; 2066 2067 mtx_assert(MNT_MTX(mp), MA_OWNED); 2068 2069 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 2070 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 2071 MNT_IUNLOCK(mp); 2072 free(*mvp, M_VNODE_MARKER); 2073 MNT_ILOCK(mp); 2074 *mvp = NULL; 2075 2076 mp->mnt_markercnt--; 2077 mp->mnt_holdcnt--; 2078 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0) 2079 wakeup(&mp->mnt_holdcnt); 2080 } 2081 2082 2083 int 2084 __vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 2085 { 2086 int error; 2087 2088 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td); 2089 if (sbp != &mp->mnt_stat) 2090 *sbp = mp->mnt_stat; 2091 return (error); 2092 } 2093 2094 void 2095 vfs_mountedfrom(struct mount *mp, const char *from) 2096 { 2097 2098 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2099 strlcpy(mp->mnt_stat.f_mntfromname, from, 2100 sizeof mp->mnt_stat.f_mntfromname); 2101 } 2102 2103 /* 2104 * --------------------------------------------------------------------- 2105 * This is the api for building mount args and mounting filesystems from 2106 * inside the kernel. 2107 * 2108 * The API works by accumulation of individual args. First error is 2109 * latched. 2110 * 2111 * XXX: should be documented in new manpage kernel_mount(9) 2112 */ 2113 2114 /* A memory allocation which must be freed when we are done */ 2115 struct mntaarg { 2116 SLIST_ENTRY(mntaarg) next; 2117 }; 2118 2119 /* The header for the mount arguments */ 2120 struct mntarg { 2121 struct iovec *v; 2122 int len; 2123 int error; 2124 SLIST_HEAD(, mntaarg) list; 2125 }; 2126 2127 /* 2128 * Add a boolean argument. 2129 * 2130 * flag is the boolean value. 2131 * name must start with "no". 2132 */ 2133 struct mntarg * 2134 mount_argb(struct mntarg *ma, int flag, const char *name) 2135 { 2136 2137 KASSERT(name[0] == 'n' && name[1] == 'o', 2138 ("mount_argb(...,%s): name must start with 'no'", name)); 2139 2140 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2141 } 2142 2143 /* 2144 * Add an argument printf style 2145 */ 2146 struct mntarg * 2147 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2148 { 2149 va_list ap; 2150 struct mntaarg *maa; 2151 struct sbuf *sb; 2152 int len; 2153 2154 if (ma == NULL) { 2155 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2156 SLIST_INIT(&ma->list); 2157 } 2158 if (ma->error) 2159 return (ma); 2160 2161 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2162 M_MOUNT, M_WAITOK); 2163 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2164 ma->v[ma->len].iov_len = strlen(name) + 1; 2165 ma->len++; 2166 2167 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 2168 va_start(ap, fmt); 2169 sbuf_vprintf(sb, fmt, ap); 2170 va_end(ap); 2171 sbuf_finish(sb); 2172 len = sbuf_len(sb) + 1; 2173 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2174 SLIST_INSERT_HEAD(&ma->list, maa, next); 2175 bcopy(sbuf_data(sb), maa + 1, len); 2176 sbuf_delete(sb); 2177 2178 ma->v[ma->len].iov_base = maa + 1; 2179 ma->v[ma->len].iov_len = len; 2180 ma->len++; 2181 2182 return (ma); 2183 } 2184 2185 /* 2186 * Add an argument which is a userland string. 2187 */ 2188 struct mntarg * 2189 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2190 { 2191 struct mntaarg *maa; 2192 char *tbuf; 2193 2194 if (val == NULL) 2195 return (ma); 2196 if (ma == NULL) { 2197 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2198 SLIST_INIT(&ma->list); 2199 } 2200 if (ma->error) 2201 return (ma); 2202 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2203 SLIST_INSERT_HEAD(&ma->list, maa, next); 2204 tbuf = (void *)(maa + 1); 2205 ma->error = copyinstr(val, tbuf, len, NULL); 2206 return (mount_arg(ma, name, tbuf, -1)); 2207 } 2208 2209 /* 2210 * Plain argument. 2211 * 2212 * If length is -1, use printf. 2213 */ 2214 struct mntarg * 2215 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2216 { 2217 2218 if (ma == NULL) { 2219 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2220 SLIST_INIT(&ma->list); 2221 } 2222 if (ma->error) 2223 return (ma); 2224 2225 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2226 M_MOUNT, M_WAITOK); 2227 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2228 ma->v[ma->len].iov_len = strlen(name) + 1; 2229 ma->len++; 2230 2231 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2232 if (len < 0) 2233 ma->v[ma->len].iov_len = strlen(val) + 1; 2234 else 2235 ma->v[ma->len].iov_len = len; 2236 ma->len++; 2237 return (ma); 2238 } 2239 2240 /* 2241 * Free a mntarg structure 2242 */ 2243 static void 2244 free_mntarg(struct mntarg *ma) 2245 { 2246 struct mntaarg *maa; 2247 2248 while (!SLIST_EMPTY(&ma->list)) { 2249 maa = SLIST_FIRST(&ma->list); 2250 SLIST_REMOVE_HEAD(&ma->list, next); 2251 free(maa, M_MOUNT); 2252 } 2253 free(ma->v, M_MOUNT); 2254 free(ma, M_MOUNT); 2255 } 2256 2257 /* 2258 * Mount a filesystem 2259 */ 2260 int 2261 kernel_mount(struct mntarg *ma, int flags) 2262 { 2263 struct uio auio; 2264 int error; 2265 2266 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2267 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2268 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2269 2270 auio.uio_iov = ma->v; 2271 auio.uio_iovcnt = ma->len; 2272 auio.uio_segflg = UIO_SYSSPACE; 2273 2274 error = ma->error; 2275 if (!error) 2276 error = vfs_donmount(curthread, flags, &auio); 2277 free_mntarg(ma); 2278 return (error); 2279 } 2280 2281 /* 2282 * A printflike function to mount a filesystem. 2283 */ 2284 int 2285 kernel_vmount(int flags, ...) 2286 { 2287 struct mntarg *ma = NULL; 2288 va_list ap; 2289 const char *cp; 2290 const void *vp; 2291 int error; 2292 2293 va_start(ap, flags); 2294 for (;;) { 2295 cp = va_arg(ap, const char *); 2296 if (cp == NULL) 2297 break; 2298 vp = va_arg(ap, const void *); 2299 ma = mount_arg(ma, cp, vp, -1); 2300 } 2301 va_end(ap); 2302 2303 error = kernel_mount(ma, flags); 2304 return (error); 2305 }
Cache object: e6e5247a3bb3c88731592880dad060b3
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