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/param.h> 64#include <sys/buf.h> 65#include <sys/module.h> 66#include <sys/systm.h> 67#include <sys/errno.h> 68#include <sys/kernel.h> 69#include <sys/capsicum.h> 70#include <sys/conf.h> 71#include <sys/filedesc.h> 72#include <sys/uio.h> 73#include <sys/malloc.h> 74#include <sys/queue.h> 75#include <sys/lock.h> 76#include <sys/sx.h> 77#include <sys/mutex.h> 78#include <sys/proc.h> 79#include <sys/vnode.h> 80#include <sys/namei.h> 81#include <sys/mount.h> 82#include <sys/sysctl.h> 83#include <sys/fcntl.h> 84 85#include "fuse.h" 86#include "fuse_node.h" 87#include "fuse_ipc.h" 88#include "fuse_internal.h" 89 90#include <sys/priv.h> 91#include <security/mac/mac_framework.h> 92 93SDT_PROVIDER_DECLARE(fusefs); 94/* 95 * Fuse trace probe: 96 * arg0: verbosity. Higher numbers give more verbose messages 97 * arg1: Textual message 98 */ 99SDT_PROBE_DEFINE2(fusefs, , vfsops, trace, "int", "char*"); 100 101/* This will do for privilege types for now */ 102#ifndef PRIV_VFS_FUSE_ALLOWOTHER 103#define PRIV_VFS_FUSE_ALLOWOTHER PRIV_VFS_MOUNT_NONUSER 104#endif 105#ifndef PRIV_VFS_FUSE_MOUNT_NONUSER 106#define PRIV_VFS_FUSE_MOUNT_NONUSER PRIV_VFS_MOUNT_NONUSER 107#endif 108#ifndef PRIV_VFS_FUSE_SYNC_UNMOUNT 109#define PRIV_VFS_FUSE_SYNC_UNMOUNT PRIV_VFS_MOUNT_NONUSER 110#endif 111 112static vfs_fhtovp_t fuse_vfsop_fhtovp; 113static vfs_mount_t fuse_vfsop_mount; 114static vfs_unmount_t fuse_vfsop_unmount; 115static vfs_root_t fuse_vfsop_root; 116static vfs_statfs_t fuse_vfsop_statfs; 117static vfs_vget_t fuse_vfsop_vget; 118 119struct vfsops fuse_vfsops = { 120 .vfs_fhtovp = fuse_vfsop_fhtovp, 121 .vfs_mount = fuse_vfsop_mount, 122 .vfs_unmount = fuse_vfsop_unmount, 123 .vfs_root = fuse_vfsop_root, 124 .vfs_statfs = fuse_vfsop_statfs, 125 .vfs_vget = fuse_vfsop_vget, 126}; 127 128static int fuse_enforce_dev_perms = 0; 129 130SYSCTL_INT(_vfs_fusefs, OID_AUTO, enforce_dev_perms, CTLFLAG_RW, 131 &fuse_enforce_dev_perms, 0, 132 "enforce fuse device permissions for secondary mounts"); 133 134MALLOC_DEFINE(M_FUSEVFS, "fuse_filesystem", "buffer for fuse vfs layer"); 135 136static int 137fuse_getdevice(const char *fspec, struct thread *td, struct cdev **fdevp) 138{ 139 struct nameidata nd, *ndp = &nd; 140 struct vnode *devvp; 141 struct cdev *fdev; 142 int err; 143 144 /* 145 * Not an update, or updating the name: look up the name 146 * and verify that it refers to a sensible disk device. 147 */ 148 149 NDINIT(ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, fspec); 150 if ((err = namei(ndp)) != 0) 151 return err; 152 NDFREE_PNBUF(ndp); 153 devvp = ndp->ni_vp; 154 155 if (devvp->v_type != VCHR) { 156 vrele(devvp); 157 return ENXIO; 158 } 159 fdev = devvp->v_rdev; 160 dev_ref(fdev); 161 162 if (fuse_enforce_dev_perms) { 163 /* 164 * Check if mounter can open the fuse device. 165 * 166 * This has significance only if we are doing a secondary mount 167 * which doesn't involve actually opening fuse devices, but we 168 * still want to enforce the permissions of the device (in 169 * order to keep control over the circle of fuse users). 170 * 171 * (In case of primary mounts, we are either the superuser so 172 * we can do anything anyway, or we can mount only if the 173 * device is already opened by us, ie. we are permitted to open 174 * the device.) 175 */ 176#if 0 177#ifdef MAC 178 err = mac_check_vnode_open(td->td_ucred, devvp, VREAD | VWRITE); 179 if (!err) 180#endif 181#endif /* 0 */ 182 err = VOP_ACCESS(devvp, VREAD | VWRITE, td->td_ucred, td); 183 if (err) { 184 vrele(devvp); 185 dev_rel(fdev); 186 return err; 187 } 188 } 189 /* 190 * according to coda code, no extra lock is needed -- 191 * although in sys/vnode.h this field is marked "v" 192 */ 193 vrele(devvp); 194 195 if (!fdev->si_devsw || 196 strcmp("fuse", fdev->si_devsw->d_name)) { 197 dev_rel(fdev); 198 return ENXIO; 199 } 200 *fdevp = fdev; 201 202 return 0; 203} 204 205#define FUSE_FLAGOPT(fnam, fval) do { \ 206 vfs_flagopt(opts, #fnam, &mntopts, fval); \ 207 vfs_flagopt(opts, "__" #fnam, &__mntopts, fval); \ 208} while (0) 209 210SDT_PROBE_DEFINE1(fusefs, , vfsops, mntopts, "uint64_t"); 211SDT_PROBE_DEFINE4(fusefs, , vfsops, mount_err, "char*", "struct fuse_data*", 212 "struct mount*", "int"); 213 214static int 215fuse_vfs_remount(struct mount *mp, struct thread *td, uint64_t mntopts, 216 uint32_t max_read, int daemon_timeout) 217{ 218 int err = 0; 219 struct fuse_data *data = fuse_get_mpdata(mp); 220 /* Don't allow these options to be changed */ 221 const static unsigned long long cant_update_opts = 222 MNT_USER; /* Mount owner must be the user running the daemon */ 223 224 FUSE_LOCK(); 225 226 if ((mp->mnt_flag ^ data->mnt_flag) & cant_update_opts) { 227 err = EOPNOTSUPP; 228 SDT_PROBE4(fusefs, , vfsops, mount_err, 229 "Can't change these mount options during remount", 230 data, mp, err); 231 goto out; 232 } 233 if (((data->dataflags ^ mntopts) & FSESS_MNTOPTS_MASK) || 234 (data->max_read != max_read) || 235 (data->daemon_timeout != daemon_timeout)) { 236 // TODO: allow changing options where it makes sense 237 err = EOPNOTSUPP; 238 SDT_PROBE4(fusefs, , vfsops, mount_err, 239 "Can't change fuse mount options during remount", 240 data, mp, err); 241 goto out; 242 } 243 244 if (fdata_get_dead(data)) { 245 err = ENOTCONN; 246 SDT_PROBE4(fusefs, , vfsops, mount_err, 247 "device is dead during mount", data, mp, err); 248 goto out; 249 } 250 251 /* Sanity + permission checks */ 252 if (!data->daemoncred) 253 panic("fuse daemon found, but identity unknown"); 254 if (mntopts & FSESS_DAEMON_CAN_SPY) 255 err = priv_check(td, PRIV_VFS_FUSE_ALLOWOTHER); 256 if (err == 0 && td->td_ucred->cr_uid != data->daemoncred->cr_uid) 257 /* are we allowed to do the first mount? */ 258 err = priv_check(td, PRIV_VFS_FUSE_MOUNT_NONUSER); 259 260out: 261 FUSE_UNLOCK(); 262 return err; 263} 264 265static int 266fuse_vfsop_fhtovp(struct mount *mp, struct fid *fhp, int flags, 267 struct vnode **vpp) 268{ 269 struct fuse_fid *ffhp = (struct fuse_fid *)fhp; 270 struct fuse_vnode_data *fvdat; 271 struct vnode *nvp; 272 int error; 273 274 if (!(fuse_get_mpdata(mp)->dataflags & FSESS_EXPORT_SUPPORT)) 275 return EOPNOTSUPP; 276 277 error = VFS_VGET(mp, ffhp->nid, LK_EXCLUSIVE, &nvp); 278 if (error) { 279 *vpp = NULLVP; 280 return (error); 281 } 282 fvdat = VTOFUD(nvp); 283 if (fvdat->generation != ffhp->gen ) { 284 vput(nvp); 285 *vpp = NULLVP; 286 return (ESTALE); 287 } 288 *vpp = nvp; 289 vnode_create_vobject(*vpp, VNODE_NO_SIZE, curthread); 290 return (0); 291} 292 293static int 294fuse_vfsop_mount(struct mount *mp) 295{ 296 int err; 297 298 uint64_t mntopts, __mntopts; 299 uint32_t max_read; 300 int linux_errnos; 301 int daemon_timeout; 302 int fd; 303 304 struct cdev *fdev; 305 struct fuse_data *data = NULL; 306 struct thread *td; 307 struct file *fp, *fptmp; 308 char *fspec, *subtype, *fsname = NULL; 309 int fsnamelen; 310 struct vfsoptlist *opts; 311 312 subtype = NULL; 313 max_read = ~0; 314 linux_errnos = 0; 315 err = 0; 316 mntopts = 0; 317 __mntopts = 0; 318 td = curthread; 319 320 /* Get the new options passed to mount */ 321 opts = mp->mnt_optnew; 322 323 if (!opts) 324 return EINVAL; 325 326 /* `fspath' contains the mount point (eg. /mnt/fuse/sshfs); REQUIRED */ 327 if (!vfs_getopts(opts, "fspath", &err)) 328 return err; 329 330 /* 331 * With the help of underscored options the mount program 332 * can inform us from the flags it sets by default 333 */ 334 FUSE_FLAGOPT(allow_other, FSESS_DAEMON_CAN_SPY); 335 FUSE_FLAGOPT(push_symlinks_in, FSESS_PUSH_SYMLINKS_IN); 336 FUSE_FLAGOPT(default_permissions, FSESS_DEFAULT_PERMISSIONS); 337 FUSE_FLAGOPT(intr, FSESS_INTR); 338 339 (void)vfs_scanopt(opts, "max_read=", "%u", &max_read); 340 (void)vfs_scanopt(opts, "linux_errnos", "%d", &linux_errnos); 341 if (vfs_scanopt(opts, "timeout=", "%u", &daemon_timeout) == 1) { 342 if (daemon_timeout < FUSE_MIN_DAEMON_TIMEOUT) 343 daemon_timeout = FUSE_MIN_DAEMON_TIMEOUT; 344 else if (daemon_timeout > FUSE_MAX_DAEMON_TIMEOUT) 345 daemon_timeout = FUSE_MAX_DAEMON_TIMEOUT; 346 } else { 347 daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 348 } 349 subtype = vfs_getopts(opts, "subtype=", &err); 350 351 SDT_PROBE1(fusefs, , vfsops, mntopts, mntopts); 352 353 if (mp->mnt_flag & MNT_UPDATE) { 354 return fuse_vfs_remount(mp, td, mntopts, max_read, 355 daemon_timeout); 356 } 357 358 /* `from' contains the device name (eg. /dev/fuse0); REQUIRED */ 359 fspec = vfs_getopts(opts, "from", &err); 360 if (!fspec) 361 return err; 362 363 /* `fd' contains the filedescriptor for this session; REQUIRED */ 364 if (vfs_scanopt(opts, "fd", "%d", &fd) != 1) 365 return EINVAL; 366 367 err = fuse_getdevice(fspec, td, &fdev); 368 if (err != 0) 369 return err; 370 371 err = fget(td, fd, &cap_read_rights, &fp); 372 if (err != 0) { 373 SDT_PROBE2(fusefs, , vfsops, trace, 1, 374 "invalid or not opened device"); 375 goto out; 376 } 377 fptmp = td->td_fpop; 378 td->td_fpop = fp; 379 err = devfs_get_cdevpriv((void **)&data); 380 td->td_fpop = fptmp; 381 fdrop(fp, td); 382 FUSE_LOCK(); 383 384 if (err != 0 || data == NULL) { 385 err = ENXIO; 386 SDT_PROBE4(fusefs, , vfsops, mount_err, 387 "invalid or not opened device", data, mp, err); 388 FUSE_UNLOCK(); 389 goto out; 390 } 391 if (fdata_get_dead(data)) { 392 err = ENOTCONN; 393 SDT_PROBE4(fusefs, , vfsops, mount_err, 394 "device is dead during mount", data, mp, err); 395 FUSE_UNLOCK(); 396 goto out; 397 } 398 /* Sanity + permission checks */ 399 if (!data->daemoncred) 400 panic("fuse daemon found, but identity unknown"); 401 if (mntopts & FSESS_DAEMON_CAN_SPY) 402 err = priv_check(td, PRIV_VFS_FUSE_ALLOWOTHER); 403 if (err == 0 && td->td_ucred->cr_uid != data->daemoncred->cr_uid) 404 /* are we allowed to do the first mount? */ 405 err = priv_check(td, PRIV_VFS_FUSE_MOUNT_NONUSER); 406 if (err) { 407 FUSE_UNLOCK(); 408 goto out; 409 } 410 data->ref++; 411 data->mp = mp; 412 data->dataflags |= mntopts; 413 data->max_read = max_read; 414 data->daemon_timeout = daemon_timeout; 415 data->linux_errnos = linux_errnos; 416 data->mnt_flag = mp->mnt_flag & MNT_UPDATEMASK; 417 FUSE_UNLOCK(); 418 419 vfs_getnewfsid(mp); 420 MNT_ILOCK(mp); 421 mp->mnt_data = data; 422 /* 423 * FUSE file systems can be either local or remote, but the kernel 424 * can't tell the difference. 425 */ 426 mp->mnt_flag &= ~MNT_LOCAL; 427 mp->mnt_kern_flag |= MNTK_USES_BCACHE; 428 /* 429 * Disable nullfs cacheing because it can consume too many resources in 430 * the FUSE server. 431 */ 432 mp->mnt_kern_flag |= MNTK_NULL_NOCACHE; 433 MNT_IUNLOCK(mp); 434 /* We need this here as this slot is used by getnewvnode() */ 435 mp->mnt_stat.f_iosize = maxbcachebuf; 436 if (subtype) { 437 strlcat(mp->mnt_stat.f_fstypename, ".", MFSNAMELEN); 438 strlcat(mp->mnt_stat.f_fstypename, subtype, MFSNAMELEN); 439 } 440 memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN); 441 vfs_getopt(opts, "fsname=", (void**)&fsname, &fsnamelen); 442 strlcpy(mp->mnt_stat.f_mntfromname, 443 fsname == NULL ? fspec : fsname, MNAMELEN); 444 mp->mnt_iosize_max = maxphys; 445 446 /* Now handshaking with daemon */ 447 fuse_internal_send_init(data, td); 448 449out: 450 if (err) { 451 FUSE_LOCK(); 452 if (data != NULL && data->mp == mp) { 453 /* 454 * Destroy device only if we acquired reference to 455 * it 456 */ 457 SDT_PROBE4(fusefs, , vfsops, mount_err, 458 "mount failed, destroy device", data, mp, err); 459 data->mp = NULL; 460 mp->mnt_data = NULL; 461 fdata_trydestroy(data); 462 } 463 FUSE_UNLOCK(); 464 dev_rel(fdev); 465 } 466 return err; 467} 468 469static int 470fuse_vfsop_unmount(struct mount *mp, int mntflags) 471{ 472 int err = 0; 473 int flags = 0; 474 475 struct cdev *fdev; 476 struct fuse_data *data; 477 struct fuse_dispatcher fdi; 478 struct thread *td = curthread; 479 480 if (mntflags & MNT_FORCE) { 481 flags |= FORCECLOSE; 482 } 483 data = fuse_get_mpdata(mp); 484 if (!data) { 485 panic("no private data for mount point?"); 486 } 487 /* There is 1 extra root vnode reference (mp->mnt_data). */ 488 FUSE_LOCK(); 489 if (data->vroot != NULL) { 490 struct vnode *vroot = data->vroot; 491 492 data->vroot = NULL; 493 FUSE_UNLOCK(); 494 vrele(vroot); 495 } else 496 FUSE_UNLOCK(); 497 err = vflush(mp, 0, flags, td); 498 if (err) { 499 return err; 500 } 501 if (fdata_get_dead(data)) { 502 goto alreadydead; 503 } 504 if (fsess_maybe_impl(mp, FUSE_DESTROY)) { 505 fdisp_init(&fdi, 0); 506 fdisp_make(&fdi, FUSE_DESTROY, mp, 0, td, NULL); 507 508 (void)fdisp_wait_answ(&fdi); 509 fdisp_destroy(&fdi); 510 } 511 512 fdata_set_dead(data); 513 514alreadydead: 515 FUSE_LOCK(); 516 data->mp = NULL; 517 fdev = data->fdev; 518 fdata_trydestroy(data); 519 FUSE_UNLOCK(); 520 521 MNT_ILOCK(mp); 522 mp->mnt_data = NULL; 523 MNT_IUNLOCK(mp); 524 525 dev_rel(fdev); 526 527 return 0; 528} 529 530SDT_PROBE_DEFINE1(fusefs, , vfsops, invalidate_without_export, 531 "struct mount*"); 532static int 533fuse_vfsop_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp) 534{ 535 struct fuse_data *data = fuse_get_mpdata(mp); 536 uint64_t nodeid = ino; 537 struct thread *td = curthread; 538 struct fuse_dispatcher fdi; 539 struct fuse_entry_out *feo; 540 struct fuse_vnode_data *fvdat; 541 struct timespec now; 542 const char dot[] = "."; 543 __enum_uint8(vtype) vtyp; 544 int error; 545 546 if (!(data->dataflags & FSESS_EXPORT_SUPPORT)) { 547 /* 548 * Unreachable unless you do something stupid, like export a 549 * nullfs mount of a fusefs file system. 550 */ 551 SDT_PROBE1(fusefs, , vfsops, invalidate_without_export, mp); 552 return (EOPNOTSUPP); 553 } 554 555 error = fuse_internal_get_cached_vnode(mp, ino, flags, vpp); 556 if (error || *vpp != NULL) 557 return error; 558 559 getnanouptime(&now); 560 561 /* Do a LOOKUP, using nodeid as the parent and "." as filename */ 562 fdisp_init(&fdi, sizeof(dot)); 563 fdisp_make(&fdi, FUSE_LOOKUP, mp, nodeid, td, td->td_ucred); 564 memcpy(fdi.indata, dot, sizeof(dot)); 565 error = fdisp_wait_answ(&fdi); 566 567 if (error) 568 return error; 569 570 feo = (struct fuse_entry_out *)fdi.answ; 571 if (feo->nodeid == 0) { 572 /* zero nodeid means ENOENT and cache it */ 573 error = ENOENT; 574 goto out; 575 } 576 577 vtyp = IFTOVT(feo->attr.mode); 578 error = fuse_vnode_get(mp, feo, nodeid, NULL, vpp, NULL, vtyp); 579 if (error) 580 goto out; 581 fvdat = VTOFUD(*vpp); 582 583 if (timespeccmp(&now, &fvdat->last_local_modify, >)) { 584 /* 585 * Attributes from the server are definitely newer than the 586 * last attributes we sent to the server, so cache them. 587 */ 588 fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid, 589 feo->attr_valid_nsec, NULL, true); 590 } 591 fuse_validity_2_bintime(feo->entry_valid, feo->entry_valid_nsec, 592 &fvdat->entry_cache_timeout); 593out: 594 fdisp_destroy(&fdi); 595 return error; 596} 597 598static int 599fuse_vfsop_root(struct mount *mp, int lkflags, struct vnode **vpp) 600{ 601 struct fuse_data *data = fuse_get_mpdata(mp); 602 int err = 0; 603 604 if (data->vroot != NULL) { 605 err = vget(data->vroot, lkflags); 606 if (err == 0) 607 *vpp = data->vroot; 608 } else { 609 err = fuse_vnode_get(mp, NULL, FUSE_ROOT_ID, NULL, vpp, NULL, 610 VDIR); 611 if (err == 0) { 612 FUSE_LOCK(); 613 MPASS(data->vroot == NULL || data->vroot == *vpp); 614 if (data->vroot == NULL) { 615 SDT_PROBE2(fusefs, , vfsops, trace, 1, 616 "new root vnode"); 617 data->vroot = *vpp; 618 FUSE_UNLOCK(); 619 vref(*vpp); 620 } else if (data->vroot != *vpp) { 621 SDT_PROBE2(fusefs, , vfsops, trace, 1, 622 "root vnode race"); 623 FUSE_UNLOCK(); 624 vput(*vpp); 625 vrecycle(*vpp); 626 *vpp = data->vroot; 627 } else 628 FUSE_UNLOCK(); 629 } 630 } 631 return err; 632} 633 634static int 635fuse_vfsop_statfs(struct mount *mp, struct statfs *sbp) 636{ 637 struct fuse_dispatcher fdi; 638 int err = 0; 639 640 struct fuse_statfs_out *fsfo; 641 struct fuse_data *data; 642 643 data = fuse_get_mpdata(mp); 644 645 if (!(data->dataflags & FSESS_INITED)) 646 goto fake; 647 648 fdisp_init(&fdi, 0); 649 fdisp_make(&fdi, FUSE_STATFS, mp, FUSE_ROOT_ID, NULL, NULL); 650 err = fdisp_wait_answ(&fdi); 651 if (err) { 652 fdisp_destroy(&fdi); 653 if (err == ENOTCONN) { 654 /* 655 * We want to seem a legitimate fs even if the daemon 656 * is stiff dead... (so that, eg., we can still do path 657 * based unmounting after the daemon dies). 658 */ 659 goto fake; 660 } 661 return err; 662 } 663 fsfo = fdi.answ; 664 665 sbp->f_blocks = fsfo->st.blocks; 666 sbp->f_bfree = fsfo->st.bfree; 667 sbp->f_bavail = fsfo->st.bavail; 668 sbp->f_files = fsfo->st.files; 669 sbp->f_ffree = fsfo->st.ffree; /* cast from uint64_t to int64_t */ 670 sbp->f_namemax = fsfo->st.namelen; 671 sbp->f_bsize = fsfo->st.frsize; /* cast from uint32_t to uint64_t */ 672 673 fdisp_destroy(&fdi); 674 return 0; 675 676fake: 677 sbp->f_blocks = 0; 678 sbp->f_bfree = 0; 679 sbp->f_bavail = 0; 680 sbp->f_files = 0; 681 sbp->f_ffree = 0; 682 sbp->f_namemax = 0; 683 sbp->f_bsize = S_BLKSIZE; 684 685 return 0; 686} 687