1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2007-2009 Google Inc. and Amit Singh 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: 10 * 11 * * Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * * Redistributions in binary form must reproduce the above 14 * copyright notice, this list of conditions and the following disclaimer 15 * in the documentation and/or other materials provided with the 16 * distribution. 17 * * Neither the name of Google Inc. nor the names of its 18 * contributors may be used to endorse or promote products derived from 19 * this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 24 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 25 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 27 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 * 33 * Copyright (C) 2005 Csaba Henk. 34 * All rights reserved. 35 * 36 * Copyright (c) 2019 The FreeBSD Foundation 37 * 38 * Portions of this software were developed by BFF Storage Systems, LLC under 39 * sponsorship from the FreeBSD Foundation. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 50 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD$"); 65 66 #include <sys/param.h> 67 #include <sys/buf.h> 68 #include <sys/module.h> 69 #include <sys/systm.h> 70 #include <sys/errno.h> 71 #include <sys/kernel.h> 72 #include <sys/capsicum.h> 73 #include <sys/conf.h> 74 #include <sys/filedesc.h> 75 #include <sys/uio.h> 76 #include <sys/malloc.h> 77 #include <sys/queue.h> 78 #include <sys/lock.h> 79 #include <sys/sx.h> 80 #include <sys/mutex.h> 81 #include <sys/proc.h> 82 #include <sys/vnode.h> 83 #include <sys/namei.h> 84 #include <sys/mount.h> 85 #include <sys/sysctl.h> 86 #include <sys/fcntl.h> 87 88 #include "fuse.h" 89 #include "fuse_node.h" 90 #include "fuse_ipc.h" 91 #include "fuse_internal.h" 92 93 #include <sys/priv.h> 94 #include <security/mac/mac_framework.h> 95 96 SDT_PROVIDER_DECLARE(fusefs); 97 /* 98 * Fuse trace probe: 99 * arg0: verbosity. Higher numbers give more verbose messages 100 * arg1: Textual message 101 */ 102 SDT_PROBE_DEFINE2(fusefs, , vfsops, trace, "int", "char*"); 103 104 /* This will do for privilege types for now */ 105 #ifndef PRIV_VFS_FUSE_ALLOWOTHER 106 #define PRIV_VFS_FUSE_ALLOWOTHER PRIV_VFS_MOUNT_NONUSER 107 #endif 108 #ifndef PRIV_VFS_FUSE_MOUNT_NONUSER 109 #define PRIV_VFS_FUSE_MOUNT_NONUSER PRIV_VFS_MOUNT_NONUSER 110 #endif 111 #ifndef PRIV_VFS_FUSE_SYNC_UNMOUNT 112 #define PRIV_VFS_FUSE_SYNC_UNMOUNT PRIV_VFS_MOUNT_NONUSER 113 #endif 114 115 static vfs_fhtovp_t fuse_vfsop_fhtovp; 116 static vfs_mount_t fuse_vfsop_mount; 117 static vfs_unmount_t fuse_vfsop_unmount; 118 static vfs_root_t fuse_vfsop_root; 119 static vfs_statfs_t fuse_vfsop_statfs; 120 static vfs_vget_t fuse_vfsop_vget; 121 122 struct vfsops fuse_vfsops = { 123 .vfs_fhtovp = fuse_vfsop_fhtovp, 124 .vfs_mount = fuse_vfsop_mount, 125 .vfs_unmount = fuse_vfsop_unmount, 126 .vfs_root = fuse_vfsop_root, 127 .vfs_statfs = fuse_vfsop_statfs, 128 .vfs_vget = fuse_vfsop_vget, 129 }; 130 131 static int fuse_enforce_dev_perms = 0; 132 133 SYSCTL_INT(_vfs_fusefs, OID_AUTO, enforce_dev_perms, CTLFLAG_RW, 134 &fuse_enforce_dev_perms, 0, 135 "enforce fuse device permissions for secondary mounts"); 136 137 MALLOC_DEFINE(M_FUSEVFS, "fuse_filesystem", "buffer for fuse vfs layer"); 138 139 static int 140 fuse_getdevice(const char *fspec, struct thread *td, struct cdev **fdevp) 141 { 142 struct nameidata nd, *ndp = &nd; 143 struct vnode *devvp; 144 struct cdev *fdev; 145 int err; 146 147 /* 148 * Not an update, or updating the name: look up the name 149 * and verify that it refers to a sensible disk device. 150 */ 151 152 NDINIT(ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, fspec); 153 if ((err = namei(ndp)) != 0) 154 return err; 155 NDFREE_PNBUF(ndp); 156 devvp = ndp->ni_vp; 157 158 if (devvp->v_type != VCHR) { 159 vrele(devvp); 160 return ENXIO; 161 } 162 fdev = devvp->v_rdev; 163 dev_ref(fdev); 164 165 if (fuse_enforce_dev_perms) { 166 /* 167 * Check if mounter can open the fuse device. 168 * 169 * This has significance only if we are doing a secondary mount 170 * which doesn't involve actually opening fuse devices, but we 171 * still want to enforce the permissions of the device (in 172 * order to keep control over the circle of fuse users). 173 * 174 * (In case of primary mounts, we are either the superuser so 175 * we can do anything anyway, or we can mount only if the 176 * device is already opened by us, ie. we are permitted to open 177 * the device.) 178 */ 179 #if 0 180 #ifdef MAC 181 err = mac_check_vnode_open(td->td_ucred, devvp, VREAD | VWRITE); 182 if (!err) 183 #endif 184 #endif /* 0 */ 185 err = VOP_ACCESS(devvp, VREAD | VWRITE, td->td_ucred, td); 186 if (err) { 187 vrele(devvp); 188 dev_rel(fdev); 189 return err; 190 } 191 } 192 /* 193 * according to coda code, no extra lock is needed -- 194 * although in sys/vnode.h this field is marked "v" 195 */ 196 vrele(devvp); 197 198 if (!fdev->si_devsw || 199 strcmp("fuse", fdev->si_devsw->d_name)) { 200 dev_rel(fdev); 201 return ENXIO; 202 } 203 *fdevp = fdev; 204 205 return 0; 206 } 207 208 #define FUSE_FLAGOPT(fnam, fval) do { \ 209 vfs_flagopt(opts, #fnam, &mntopts, fval); \ 210 vfs_flagopt(opts, "__" #fnam, &__mntopts, fval); \ 211 } while (0) 212 213 SDT_PROBE_DEFINE1(fusefs, , vfsops, mntopts, "uint64_t"); 214 SDT_PROBE_DEFINE4(fusefs, , vfsops, mount_err, "char*", "struct fuse_data*", 215 "struct mount*", "int"); 216 217 static int 218 fuse_vfs_remount(struct mount *mp, struct thread *td, uint64_t mntopts, 219 uint32_t max_read, int daemon_timeout) 220 { 221 int err = 0; 222 struct fuse_data *data = fuse_get_mpdata(mp); 223 /* Don't allow these options to be changed */ 224 const static unsigned long long cant_update_opts = 225 MNT_USER; /* Mount owner must be the user running the daemon */ 226 227 FUSE_LOCK(); 228 229 if ((mp->mnt_flag ^ data->mnt_flag) & cant_update_opts) { 230 err = EOPNOTSUPP; 231 SDT_PROBE4(fusefs, , vfsops, mount_err, 232 "Can't change these mount options during remount", 233 data, mp, err); 234 goto out; 235 } 236 if (((data->dataflags ^ mntopts) & FSESS_MNTOPTS_MASK) || 237 (data->max_read != max_read) || 238 (data->daemon_timeout != daemon_timeout)) { 239 // TODO: allow changing options where it makes sense 240 err = EOPNOTSUPP; 241 SDT_PROBE4(fusefs, , vfsops, mount_err, 242 "Can't change fuse mount options during remount", 243 data, mp, err); 244 goto out; 245 } 246 247 if (fdata_get_dead(data)) { 248 err = ENOTCONN; 249 SDT_PROBE4(fusefs, , vfsops, mount_err, 250 "device is dead during mount", data, mp, err); 251 goto out; 252 } 253 254 /* Sanity + permission checks */ 255 if (!data->daemoncred) 256 panic("fuse daemon found, but identity unknown"); 257 if (mntopts & FSESS_DAEMON_CAN_SPY) 258 err = priv_check(td, PRIV_VFS_FUSE_ALLOWOTHER); 259 if (err == 0 && td->td_ucred->cr_uid != data->daemoncred->cr_uid) 260 /* are we allowed to do the first mount? */ 261 err = priv_check(td, PRIV_VFS_FUSE_MOUNT_NONUSER); 262 263 out: 264 FUSE_UNLOCK(); 265 return err; 266 } 267 268 static int 269 fuse_vfsop_fhtovp(struct mount *mp, struct fid *fhp, int flags, 270 struct vnode **vpp) 271 { 272 struct fuse_fid *ffhp = (struct fuse_fid *)fhp; 273 struct fuse_vnode_data *fvdat; 274 struct vnode *nvp; 275 int error; 276 277 if (!(fuse_get_mpdata(mp)->dataflags & FSESS_EXPORT_SUPPORT)) 278 return EOPNOTSUPP; 279 280 error = VFS_VGET(mp, ffhp->nid, LK_EXCLUSIVE, &nvp); 281 if (error) { 282 *vpp = NULLVP; 283 return (error); 284 } 285 fvdat = VTOFUD(nvp); 286 if (fvdat->generation != ffhp->gen ) { 287 vput(nvp); 288 *vpp = NULLVP; 289 return (ESTALE); 290 } 291 *vpp = nvp; 292 vnode_create_vobject(*vpp, 0, curthread); 293 return (0); 294 } 295 296 static int 297 fuse_vfsop_mount(struct mount *mp) 298 { 299 int err; 300 301 uint64_t mntopts, __mntopts; 302 uint32_t max_read; 303 int linux_errnos; 304 int daemon_timeout; 305 int fd; 306 307 struct cdev *fdev; 308 struct fuse_data *data = NULL; 309 struct thread *td; 310 struct file *fp, *fptmp; 311 char *fspec, *subtype, *fsname = NULL; 312 int fsnamelen; 313 struct vfsoptlist *opts; 314 315 subtype = NULL; 316 max_read = ~0; 317 linux_errnos = 0; 318 err = 0; 319 mntopts = 0; 320 __mntopts = 0; 321 td = curthread; 322 323 /* Get the new options passed to mount */ 324 opts = mp->mnt_optnew; 325 326 if (!opts) 327 return EINVAL; 328 329 /* `fspath' contains the mount point (eg. /mnt/fuse/sshfs); REQUIRED */ 330 if (!vfs_getopts(opts, "fspath", &err)) 331 return err; 332 333 /* 334 * With the help of underscored options the mount program 335 * can inform us from the flags it sets by default 336 */ 337 FUSE_FLAGOPT(allow_other, FSESS_DAEMON_CAN_SPY); 338 FUSE_FLAGOPT(push_symlinks_in, FSESS_PUSH_SYMLINKS_IN); 339 FUSE_FLAGOPT(default_permissions, FSESS_DEFAULT_PERMISSIONS); 340 FUSE_FLAGOPT(intr, FSESS_INTR); 341 342 (void)vfs_scanopt(opts, "max_read=", "%u", &max_read); 343 (void)vfs_scanopt(opts, "linux_errnos", "%d", &linux_errnos); 344 if (vfs_scanopt(opts, "timeout=", "%u", &daemon_timeout) == 1) { 345 if (daemon_timeout < FUSE_MIN_DAEMON_TIMEOUT) 346 daemon_timeout = FUSE_MIN_DAEMON_TIMEOUT; 347 else if (daemon_timeout > FUSE_MAX_DAEMON_TIMEOUT) 348 daemon_timeout = FUSE_MAX_DAEMON_TIMEOUT; 349 } else { 350 daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 351 } 352 subtype = vfs_getopts(opts, "subtype=", &err); 353 354 SDT_PROBE1(fusefs, , vfsops, mntopts, mntopts); 355 356 if (mp->mnt_flag & MNT_UPDATE) { 357 return fuse_vfs_remount(mp, td, mntopts, max_read, 358 daemon_timeout); 359 } 360 361 /* `from' contains the device name (eg. /dev/fuse0); REQUIRED */ 362 fspec = vfs_getopts(opts, "from", &err); 363 if (!fspec) 364 return err; 365 366 /* `fd' contains the filedescriptor for this session; REQUIRED */ 367 if (vfs_scanopt(opts, "fd", "%d", &fd) != 1) 368 return EINVAL; 369 370 err = fuse_getdevice(fspec, td, &fdev); 371 if (err != 0) 372 return err; 373 374 err = fget(td, fd, &cap_read_rights, &fp); 375 if (err != 0) { 376 SDT_PROBE2(fusefs, , vfsops, trace, 1, 377 "invalid or not opened device"); 378 goto out; 379 } 380 fptmp = td->td_fpop; 381 td->td_fpop = fp; 382 err = devfs_get_cdevpriv((void **)&data); 383 td->td_fpop = fptmp; 384 fdrop(fp, td); 385 FUSE_LOCK(); 386 387 if (err != 0 || data == NULL) { 388 err = ENXIO; 389 SDT_PROBE4(fusefs, , vfsops, mount_err, 390 "invalid or not opened device", data, mp, err); 391 FUSE_UNLOCK(); 392 goto out; 393 } 394 if (fdata_get_dead(data)) { 395 err = ENOTCONN; 396 SDT_PROBE4(fusefs, , vfsops, mount_err, 397 "device is dead during mount", data, mp, err); 398 FUSE_UNLOCK(); 399 goto out; 400 } 401 /* Sanity + permission checks */ 402 if (!data->daemoncred) 403 panic("fuse daemon found, but identity unknown"); 404 if (mntopts & FSESS_DAEMON_CAN_SPY) 405 err = priv_check(td, PRIV_VFS_FUSE_ALLOWOTHER); 406 if (err == 0 && td->td_ucred->cr_uid != data->daemoncred->cr_uid) 407 /* are we allowed to do the first mount? */ 408 err = priv_check(td, PRIV_VFS_FUSE_MOUNT_NONUSER); 409 if (err) { 410 FUSE_UNLOCK(); 411 goto out; 412 } 413 data->ref++; 414 data->mp = mp; 415 data->dataflags |= mntopts; 416 data->max_read = max_read; 417 data->daemon_timeout = daemon_timeout; 418 data->linux_errnos = linux_errnos; 419 data->mnt_flag = mp->mnt_flag & MNT_UPDATEMASK; 420 FUSE_UNLOCK(); 421 422 vfs_getnewfsid(mp); 423 MNT_ILOCK(mp); 424 mp->mnt_data = data; 425 /* 426 * FUSE file systems can be either local or remote, but the kernel 427 * can't tell the difference. 428 */ 429 mp->mnt_flag &= ~MNT_LOCAL; 430 mp->mnt_kern_flag |= MNTK_USES_BCACHE; 431 /* 432 * Disable nullfs cacheing because it can consume too many resources in 433 * the FUSE server. 434 */ 435 mp->mnt_kern_flag |= MNTK_NULL_NOCACHE; 436 MNT_IUNLOCK(mp); 437 /* We need this here as this slot is used by getnewvnode() */ 438 mp->mnt_stat.f_iosize = maxbcachebuf; 439 if (subtype) { 440 strlcat(mp->mnt_stat.f_fstypename, ".", MFSNAMELEN); 441 strlcat(mp->mnt_stat.f_fstypename, subtype, MFSNAMELEN); 442 } 443 memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN); 444 vfs_getopt(opts, "fsname=", (void**)&fsname, &fsnamelen); 445 strlcpy(mp->mnt_stat.f_mntfromname, 446 fsname == NULL ? fspec : fsname, MNAMELEN); 447 mp->mnt_iosize_max = maxphys; 448 449 /* Now handshaking with daemon */ 450 fuse_internal_send_init(data, td); 451 452 out: 453 if (err) { 454 FUSE_LOCK(); 455 if (data != NULL && data->mp == mp) { 456 /* 457 * Destroy device only if we acquired reference to 458 * it 459 */ 460 SDT_PROBE4(fusefs, , vfsops, mount_err, 461 "mount failed, destroy device", data, mp, err); 462 data->mp = NULL; 463 mp->mnt_data = NULL; 464 fdata_trydestroy(data); 465 } 466 FUSE_UNLOCK(); 467 dev_rel(fdev); 468 } 469 return err; 470 } 471 472 static int 473 fuse_vfsop_unmount(struct mount *mp, int mntflags) 474 { 475 int err = 0; 476 int flags = 0; 477 478 struct cdev *fdev; 479 struct fuse_data *data; 480 struct fuse_dispatcher fdi; 481 struct thread *td = curthread; 482 483 if (mntflags & MNT_FORCE) { 484 flags |= FORCECLOSE; 485 } 486 data = fuse_get_mpdata(mp); 487 if (!data) { 488 panic("no private data for mount point?"); 489 } 490 /* There is 1 extra root vnode reference (mp->mnt_data). */ 491 FUSE_LOCK(); 492 if (data->vroot != NULL) { 493 struct vnode *vroot = data->vroot; 494 495 data->vroot = NULL; 496 FUSE_UNLOCK(); 497 vrele(vroot); 498 } else 499 FUSE_UNLOCK(); 500 err = vflush(mp, 0, flags, td); 501 if (err) { 502 return err; 503 } 504 if (fdata_get_dead(data)) { 505 goto alreadydead; 506 } 507 if (fsess_maybe_impl(mp, FUSE_DESTROY)) { 508 fdisp_init(&fdi, 0); 509 fdisp_make(&fdi, FUSE_DESTROY, mp, 0, td, NULL); 510 511 (void)fdisp_wait_answ(&fdi); 512 fdisp_destroy(&fdi); 513 } 514 515 fdata_set_dead(data); 516 517 alreadydead: 518 FUSE_LOCK(); 519 data->mp = NULL; 520 fdev = data->fdev; 521 fdata_trydestroy(data); 522 FUSE_UNLOCK(); 523 524 MNT_ILOCK(mp); 525 mp->mnt_data = NULL; 526 MNT_IUNLOCK(mp); 527 528 dev_rel(fdev); 529 530 return 0; 531 } 532 533 SDT_PROBE_DEFINE1(fusefs, , vfsops, invalidate_without_export, 534 "struct mount*"); 535 static int 536 fuse_vfsop_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp) 537 { 538 struct fuse_data *data = fuse_get_mpdata(mp); 539 uint64_t nodeid = ino; 540 struct thread *td = curthread; 541 struct fuse_dispatcher fdi; 542 struct fuse_entry_out *feo; 543 struct fuse_vnode_data *fvdat; 544 struct timespec now; 545 const char dot[] = "."; 546 enum vtype vtyp; 547 int error; 548 549 if (!(data->dataflags & FSESS_EXPORT_SUPPORT)) { 550 /* 551 * Unreachable unless you do something stupid, like export a 552 * nullfs mount of a fusefs file system. 553 */ 554 SDT_PROBE1(fusefs, , vfsops, invalidate_without_export, mp); 555 return (EOPNOTSUPP); 556 } 557 558 error = fuse_internal_get_cached_vnode(mp, ino, flags, vpp); 559 if (error || *vpp != NULL) 560 return error; 561 562 getnanouptime(&now); 563 564 /* Do a LOOKUP, using nodeid as the parent and "." as filename */ 565 fdisp_init(&fdi, sizeof(dot)); 566 fdisp_make(&fdi, FUSE_LOOKUP, mp, nodeid, td, td->td_ucred); 567 memcpy(fdi.indata, dot, sizeof(dot)); 568 error = fdisp_wait_answ(&fdi); 569 570 if (error) 571 return error; 572 573 feo = (struct fuse_entry_out *)fdi.answ; 574 if (feo->nodeid == 0) { 575 /* zero nodeid means ENOENT and cache it */ 576 error = ENOENT; 577 goto out; 578 } 579 580 vtyp = IFTOVT(feo->attr.mode); 581 error = fuse_vnode_get(mp, feo, nodeid, NULL, vpp, NULL, vtyp); 582 if (error) 583 goto out; 584 fvdat = VTOFUD(*vpp); 585 586 if (timespeccmp(&now, &fvdat->last_local_modify, >)) { 587 /* 588 * Attributes from the server are definitely newer than the 589 * last attributes we sent to the server, so cache them. 590 */ 591 fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid, 592 feo->attr_valid_nsec, NULL, true); 593 } 594 fuse_validity_2_bintime(feo->entry_valid, feo->entry_valid_nsec, 595 &fvdat->entry_cache_timeout); 596 out: 597 fdisp_destroy(&fdi); 598 return error; 599 } 600 601 static int 602 fuse_vfsop_root(struct mount *mp, int lkflags, struct vnode **vpp) 603 { 604 struct fuse_data *data = fuse_get_mpdata(mp); 605 int err = 0; 606 607 if (data->vroot != NULL) { 608 err = vget(data->vroot, lkflags); 609 if (err == 0) 610 *vpp = data->vroot; 611 } else { 612 err = fuse_vnode_get(mp, NULL, FUSE_ROOT_ID, NULL, vpp, NULL, 613 VDIR); 614 if (err == 0) { 615 FUSE_LOCK(); 616 MPASS(data->vroot == NULL || data->vroot == *vpp); 617 if (data->vroot == NULL) { 618 SDT_PROBE2(fusefs, , vfsops, trace, 1, 619 "new root vnode"); 620 data->vroot = *vpp; 621 FUSE_UNLOCK(); 622 vref(*vpp); 623 } else if (data->vroot != *vpp) { 624 SDT_PROBE2(fusefs, , vfsops, trace, 1, 625 "root vnode race"); 626 FUSE_UNLOCK(); 627 vput(*vpp); 628 vrecycle(*vpp); 629 *vpp = data->vroot; 630 } else 631 FUSE_UNLOCK(); 632 } 633 } 634 return err; 635 } 636 637 static int 638 fuse_vfsop_statfs(struct mount *mp, struct statfs *sbp) 639 { 640 struct fuse_dispatcher fdi; 641 int err = 0; 642 643 struct fuse_statfs_out *fsfo; 644 struct fuse_data *data; 645 646 data = fuse_get_mpdata(mp); 647 648 if (!(data->dataflags & FSESS_INITED)) 649 goto fake; 650 651 fdisp_init(&fdi, 0); 652 fdisp_make(&fdi, FUSE_STATFS, mp, FUSE_ROOT_ID, NULL, NULL); 653 err = fdisp_wait_answ(&fdi); 654 if (err) { 655 fdisp_destroy(&fdi); 656 if (err == ENOTCONN) { 657 /* 658 * We want to seem a legitimate fs even if the daemon 659 * is stiff dead... (so that, eg., we can still do path 660 * based unmounting after the daemon dies). 661 */ 662 goto fake; 663 } 664 return err; 665 } 666 fsfo = fdi.answ; 667 668 sbp->f_blocks = fsfo->st.blocks; 669 sbp->f_bfree = fsfo->st.bfree; 670 sbp->f_bavail = fsfo->st.bavail; 671 sbp->f_files = fsfo->st.files; 672 sbp->f_ffree = fsfo->st.ffree; /* cast from uint64_t to int64_t */ 673 sbp->f_namemax = fsfo->st.namelen; 674 sbp->f_bsize = fsfo->st.frsize; /* cast from uint32_t to uint64_t */ 675 676 fdisp_destroy(&fdi); 677 return 0; 678 679 fake: 680 sbp->f_blocks = 0; 681 sbp->f_bfree = 0; 682 sbp->f_bavail = 0; 683 sbp->f_files = 0; 684 sbp->f_ffree = 0; 685 sbp->f_namemax = 0; 686 sbp->f_bsize = S_BLKSIZE; 687 688 return 0; 689 } 690