xref: /freebsd/sys/fs/fuse/fuse_vnops.c (revision abdcd967dc0c81500cc5523b530193554846f176)
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/module.h>
68 #include <sys/systm.h>
69 #include <sys/errno.h>
70 #include <sys/kernel.h>
71 #include <sys/conf.h>
72 #include <sys/filio.h>
73 #include <sys/uio.h>
74 #include <sys/malloc.h>
75 #include <sys/queue.h>
76 #include <sys/limits.h>
77 #include <sys/lock.h>
78 #include <sys/rwlock.h>
79 #include <sys/sx.h>
80 #include <sys/proc.h>
81 #include <sys/mount.h>
82 #include <sys/vnode.h>
83 #include <sys/namei.h>
84 #include <sys/extattr.h>
85 #include <sys/stat.h>
86 #include <sys/unistd.h>
87 #include <sys/filedesc.h>
88 #include <sys/file.h>
89 #include <sys/fcntl.h>
90 #include <sys/dirent.h>
91 #include <sys/bio.h>
92 #include <sys/buf.h>
93 #include <sys/sysctl.h>
94 #include <sys/vmmeter.h>
95 
96 #include <vm/vm.h>
97 #include <vm/vm_extern.h>
98 #include <vm/pmap.h>
99 #include <vm/vm_map.h>
100 #include <vm/vm_page.h>
101 #include <vm/vm_param.h>
102 #include <vm/vm_object.h>
103 #include <vm/vm_pager.h>
104 #include <vm/vnode_pager.h>
105 #include <vm/vm_object.h>
106 
107 #include "fuse.h"
108 #include "fuse_file.h"
109 #include "fuse_internal.h"
110 #include "fuse_ipc.h"
111 #include "fuse_node.h"
112 #include "fuse_io.h"
113 
114 #include <sys/priv.h>
115 
116 /* Maximum number of hardlinks to a single FUSE file */
117 #define FUSE_LINK_MAX                      UINT32_MAX
118 
119 SDT_PROVIDER_DECLARE(fusefs);
120 /*
121  * Fuse trace probe:
122  * arg0: verbosity.  Higher numbers give more verbose messages
123  * arg1: Textual message
124  */
125 SDT_PROBE_DEFINE2(fusefs, , vnops, trace, "int", "char*");
126 
127 /* vnode ops */
128 static vop_access_t fuse_vnop_access;
129 static vop_advlock_t fuse_vnop_advlock;
130 static vop_allocate_t fuse_vnop_allocate;
131 static vop_bmap_t fuse_vnop_bmap;
132 static vop_close_t fuse_fifo_close;
133 static vop_close_t fuse_vnop_close;
134 static vop_copy_file_range_t fuse_vnop_copy_file_range;
135 static vop_create_t fuse_vnop_create;
136 static vop_deallocate_t fuse_vnop_deallocate;
137 static vop_deleteextattr_t fuse_vnop_deleteextattr;
138 static vop_fdatasync_t fuse_vnop_fdatasync;
139 static vop_fsync_t fuse_vnop_fsync;
140 static vop_getattr_t fuse_vnop_getattr;
141 static vop_getextattr_t fuse_vnop_getextattr;
142 static vop_inactive_t fuse_vnop_inactive;
143 static vop_ioctl_t fuse_vnop_ioctl;
144 static vop_link_t fuse_vnop_link;
145 static vop_listextattr_t fuse_vnop_listextattr;
146 static vop_lookup_t fuse_vnop_lookup;
147 static vop_mkdir_t fuse_vnop_mkdir;
148 static vop_mknod_t fuse_vnop_mknod;
149 static vop_open_t fuse_vnop_open;
150 static vop_pathconf_t fuse_vnop_pathconf;
151 static vop_read_t fuse_vnop_read;
152 static vop_readdir_t fuse_vnop_readdir;
153 static vop_readlink_t fuse_vnop_readlink;
154 static vop_reclaim_t fuse_vnop_reclaim;
155 static vop_remove_t fuse_vnop_remove;
156 static vop_rename_t fuse_vnop_rename;
157 static vop_rmdir_t fuse_vnop_rmdir;
158 static vop_setattr_t fuse_vnop_setattr;
159 static vop_setextattr_t fuse_vnop_setextattr;
160 static vop_strategy_t fuse_vnop_strategy;
161 static vop_symlink_t fuse_vnop_symlink;
162 static vop_write_t fuse_vnop_write;
163 static vop_getpages_t fuse_vnop_getpages;
164 static vop_print_t fuse_vnop_print;
165 static vop_vptofh_t fuse_vnop_vptofh;
166 
167 struct vop_vector fuse_fifoops = {
168 	.vop_default =		&fifo_specops,
169 	.vop_access =		fuse_vnop_access,
170 	.vop_close =		fuse_fifo_close,
171 	.vop_fsync =		fuse_vnop_fsync,
172 	.vop_getattr =		fuse_vnop_getattr,
173 	.vop_inactive =		fuse_vnop_inactive,
174 	.vop_pathconf =		fuse_vnop_pathconf,
175 	.vop_print =		fuse_vnop_print,
176 	.vop_read =		VOP_PANIC,
177 	.vop_reclaim =		fuse_vnop_reclaim,
178 	.vop_setattr =		fuse_vnop_setattr,
179 	.vop_write =		VOP_PANIC,
180 	.vop_vptofh =		fuse_vnop_vptofh,
181 };
182 VFS_VOP_VECTOR_REGISTER(fuse_fifoops);
183 
184 struct vop_vector fuse_vnops = {
185 	.vop_allocate =	fuse_vnop_allocate,
186 	.vop_default = &default_vnodeops,
187 	.vop_access = fuse_vnop_access,
188 	.vop_advlock = fuse_vnop_advlock,
189 	.vop_bmap = fuse_vnop_bmap,
190 	.vop_close = fuse_vnop_close,
191 	.vop_copy_file_range = fuse_vnop_copy_file_range,
192 	.vop_create = fuse_vnop_create,
193 	.vop_deallocate = fuse_vnop_deallocate,
194 	.vop_deleteextattr = fuse_vnop_deleteextattr,
195 	.vop_fsync = fuse_vnop_fsync,
196 	.vop_fdatasync = fuse_vnop_fdatasync,
197 	.vop_getattr = fuse_vnop_getattr,
198 	.vop_getextattr = fuse_vnop_getextattr,
199 	.vop_inactive = fuse_vnop_inactive,
200 	.vop_ioctl = fuse_vnop_ioctl,
201 	.vop_link = fuse_vnop_link,
202 	.vop_listextattr = fuse_vnop_listextattr,
203 	.vop_lookup = fuse_vnop_lookup,
204 	.vop_mkdir = fuse_vnop_mkdir,
205 	.vop_mknod = fuse_vnop_mknod,
206 	.vop_open = fuse_vnop_open,
207 	.vop_pathconf = fuse_vnop_pathconf,
208 	/*
209 	 * TODO: implement vop_poll after upgrading to protocol 7.21.
210 	 * FUSE_POLL was added in protocol 7.11, but it's kind of broken until
211 	 * 7.21, which adds the ability for the client to choose which poll
212 	 * events it wants, and for a client to deregister a file handle
213 	 */
214 	.vop_read = fuse_vnop_read,
215 	.vop_readdir = fuse_vnop_readdir,
216 	.vop_readlink = fuse_vnop_readlink,
217 	.vop_reclaim = fuse_vnop_reclaim,
218 	.vop_remove = fuse_vnop_remove,
219 	.vop_rename = fuse_vnop_rename,
220 	.vop_rmdir = fuse_vnop_rmdir,
221 	.vop_setattr = fuse_vnop_setattr,
222 	.vop_setextattr = fuse_vnop_setextattr,
223 	.vop_strategy = fuse_vnop_strategy,
224 	.vop_symlink = fuse_vnop_symlink,
225 	.vop_write = fuse_vnop_write,
226 	.vop_getpages = fuse_vnop_getpages,
227 	.vop_print = fuse_vnop_print,
228 	.vop_vptofh = fuse_vnop_vptofh,
229 };
230 VFS_VOP_VECTOR_REGISTER(fuse_vnops);
231 
232 uma_zone_t fuse_pbuf_zone;
233 
234 /* Check permission for extattr operations, much like extattr_check_cred */
235 static int
236 fuse_extattr_check_cred(struct vnode *vp, int ns, struct ucred *cred,
237 	struct thread *td, accmode_t accmode)
238 {
239 	struct mount *mp = vnode_mount(vp);
240 	struct fuse_data *data = fuse_get_mpdata(mp);
241 	int default_permissions = data->dataflags & FSESS_DEFAULT_PERMISSIONS;
242 
243 	/*
244 	 * Kernel-invoked always succeeds.
245 	 */
246 	if (cred == NOCRED)
247 		return (0);
248 
249 	/*
250 	 * Do not allow privileged processes in jail to directly manipulate
251 	 * system attributes.
252 	 */
253 	switch (ns) {
254 	case EXTATTR_NAMESPACE_SYSTEM:
255 		if (default_permissions) {
256 			return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM));
257 		}
258 		return (0);
259 	case EXTATTR_NAMESPACE_USER:
260 		if (default_permissions) {
261 			return (fuse_internal_access(vp, accmode, td, cred));
262 		}
263 		return (0);
264 	default:
265 		return (EPERM);
266 	}
267 }
268 
269 /* Get a filehandle for a directory */
270 static int
271 fuse_filehandle_get_dir(struct vnode *vp, struct fuse_filehandle **fufhp,
272 	struct ucred *cred, pid_t pid)
273 {
274 	if (fuse_filehandle_get(vp, FREAD, fufhp, cred, pid) == 0)
275 		return 0;
276 	return fuse_filehandle_get(vp, FEXEC, fufhp, cred, pid);
277 }
278 
279 /* Send FUSE_FLUSH for this vnode */
280 static int
281 fuse_flush(struct vnode *vp, struct ucred *cred, pid_t pid, int fflag)
282 {
283 	struct fuse_flush_in *ffi;
284 	struct fuse_filehandle *fufh;
285 	struct fuse_dispatcher fdi;
286 	struct thread *td = curthread;
287 	struct mount *mp = vnode_mount(vp);
288 	int err;
289 
290 	if (fsess_not_impl(vnode_mount(vp), FUSE_FLUSH))
291 		return 0;
292 
293 	err = fuse_filehandle_getrw(vp, fflag, &fufh, cred, pid);
294 	if (err)
295 		return err;
296 
297 	fdisp_init(&fdi, sizeof(*ffi));
298 	fdisp_make_vp(&fdi, FUSE_FLUSH, vp, td, cred);
299 	ffi = fdi.indata;
300 	ffi->fh = fufh->fh_id;
301 	/*
302 	 * If the file has a POSIX lock then we're supposed to set lock_owner.
303 	 * If not, then lock_owner is undefined.  So we may as well always set
304 	 * it.
305 	 */
306 	ffi->lock_owner = td->td_proc->p_pid;
307 
308 	err = fdisp_wait_answ(&fdi);
309 	if (err == ENOSYS) {
310 		fsess_set_notimpl(mp, FUSE_FLUSH);
311 		err = 0;
312 	}
313 	fdisp_destroy(&fdi);
314 	return err;
315 }
316 
317 /* Close wrapper for fifos.  */
318 static int
319 fuse_fifo_close(struct vop_close_args *ap)
320 {
321 	return (fifo_specops.vop_close(ap));
322 }
323 
324 /* Invalidate a range of cached data, whether dirty of not */
325 static int
326 fuse_inval_buf_range(struct vnode *vp, off_t filesize, off_t start, off_t end)
327 {
328 	struct buf *bp;
329 	daddr_t left_lbn, end_lbn, right_lbn;
330 	off_t new_filesize;
331 	int iosize, left_on, right_on, right_blksize;
332 
333 	iosize = fuse_iosize(vp);
334 	left_lbn = start / iosize;
335 	end_lbn = howmany(end, iosize);
336 	left_on = start & (iosize - 1);
337 	if (left_on != 0) {
338 		bp = getblk(vp, left_lbn, iosize, PCATCH, 0, 0);
339 		if ((bp->b_flags & B_CACHE) != 0 && bp->b_dirtyend >= left_on) {
340 			/*
341 			 * Flush the dirty buffer, because we don't have a
342 			 * byte-granular way to record which parts of the
343 			 * buffer are valid.
344 			 */
345 			bwrite(bp);
346 			if (bp->b_error)
347 				return (bp->b_error);
348 		} else {
349 			brelse(bp);
350 		}
351 	}
352 	right_on = end & (iosize - 1);
353 	if (right_on != 0) {
354 		right_lbn = end / iosize;
355 		new_filesize = MAX(filesize, end);
356 		right_blksize = MIN(iosize, new_filesize - iosize * right_lbn);
357 		bp = getblk(vp, right_lbn, right_blksize, PCATCH, 0, 0);
358 		if ((bp->b_flags & B_CACHE) != 0 && bp->b_dirtyoff < right_on) {
359 			/*
360 			 * Flush the dirty buffer, because we don't have a
361 			 * byte-granular way to record which parts of the
362 			 * buffer are valid.
363 			 */
364 			bwrite(bp);
365 			if (bp->b_error)
366 				return (bp->b_error);
367 		} else {
368 			brelse(bp);
369 		}
370 	}
371 
372 	v_inval_buf_range(vp, left_lbn, end_lbn, iosize);
373 	return (0);
374 }
375 
376 
377 /* Send FUSE_LSEEK for this node */
378 static int
379 fuse_vnop_do_lseek(struct vnode *vp, struct thread *td, struct ucred *cred,
380 	pid_t pid, off_t *offp, int whence)
381 {
382 	struct fuse_dispatcher fdi;
383 	struct fuse_filehandle *fufh;
384 	struct fuse_lseek_in *flsi;
385 	struct fuse_lseek_out *flso;
386 	struct mount *mp = vnode_mount(vp);
387 	int err;
388 
389 	ASSERT_VOP_LOCKED(vp, __func__);
390 
391 	err = fuse_filehandle_getrw(vp, FREAD, &fufh, cred, pid);
392 	if (err)
393 		return (err);
394 	fdisp_init(&fdi, sizeof(*flsi));
395 	fdisp_make_vp(&fdi, FUSE_LSEEK, vp, td, cred);
396 	flsi = fdi.indata;
397 	flsi->fh = fufh->fh_id;
398 	flsi->offset = *offp;
399 	flsi->whence = whence;
400 	err = fdisp_wait_answ(&fdi);
401 	if (err == ENOSYS) {
402 		fsess_set_notimpl(mp, FUSE_LSEEK);
403 	} else if (err == 0) {
404 		fsess_set_impl(mp, FUSE_LSEEK);
405 		flso = fdi.answ;
406 		*offp = flso->offset;
407 	}
408 	fdisp_destroy(&fdi);
409 
410 	return (err);
411 }
412 
413 /*
414     struct vnop_access_args {
415 	struct vnode *a_vp;
416 #if VOP_ACCESS_TAKES_ACCMODE_T
417 	accmode_t a_accmode;
418 #else
419 	int a_mode;
420 #endif
421 	struct ucred *a_cred;
422 	struct thread *a_td;
423     };
424 */
425 static int
426 fuse_vnop_access(struct vop_access_args *ap)
427 {
428 	struct vnode *vp = ap->a_vp;
429 	int accmode = ap->a_accmode;
430 	struct ucred *cred = ap->a_cred;
431 
432 	struct fuse_data *data = fuse_get_mpdata(vnode_mount(vp));
433 
434 	int err;
435 
436 	if (fuse_isdeadfs(vp)) {
437 		if (vnode_isvroot(vp)) {
438 			return 0;
439 		}
440 		return ENXIO;
441 	}
442 	if (!(data->dataflags & FSESS_INITED)) {
443 		if (vnode_isvroot(vp)) {
444 			if (priv_check_cred(cred, PRIV_VFS_ADMIN) ||
445 			    (fuse_match_cred(data->daemoncred, cred) == 0)) {
446 				return 0;
447 			}
448 		}
449 		return EBADF;
450 	}
451 	if (vnode_islnk(vp)) {
452 		return 0;
453 	}
454 
455 	err = fuse_internal_access(vp, accmode, ap->a_td, ap->a_cred);
456 	return err;
457 }
458 
459 /*
460  * struct vop_advlock_args {
461  *	struct vop_generic_args a_gen;
462  *	struct vnode *a_vp;
463  *	void *a_id;
464  *	int a_op;
465  *	struct flock *a_fl;
466  *	int a_flags;
467  * }
468  */
469 static int
470 fuse_vnop_advlock(struct vop_advlock_args *ap)
471 {
472 	struct vnode *vp = ap->a_vp;
473 	struct flock *fl = ap->a_fl;
474 	struct thread *td = curthread;
475 	struct ucred *cred = td->td_ucred;
476 	pid_t pid = td->td_proc->p_pid;
477 	struct fuse_filehandle *fufh;
478 	struct fuse_dispatcher fdi;
479 	struct fuse_lk_in *fli;
480 	struct fuse_lk_out *flo;
481 	enum fuse_opcode op;
482 	int dataflags, err;
483 	int flags = ap->a_flags;
484 
485 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
486 
487 	if (fuse_isdeadfs(vp)) {
488 		return ENXIO;
489 	}
490 
491 	switch(ap->a_op) {
492 	case F_GETLK:
493 		op = FUSE_GETLK;
494 		break;
495 	case F_SETLK:
496 		if (flags & F_WAIT)
497 			op = FUSE_SETLKW;
498 		else
499 			op = FUSE_SETLK;
500 		break;
501 	case F_UNLCK:
502 		op = FUSE_SETLK;
503 		break;
504 	default:
505 		return EINVAL;
506 	}
507 
508 	if (!(dataflags & FSESS_POSIX_LOCKS))
509 		return vop_stdadvlock(ap);
510 	/* FUSE doesn't properly support flock until protocol 7.17 */
511 	if (flags & F_FLOCK)
512 		return vop_stdadvlock(ap);
513 
514 	vn_lock(vp, LK_SHARED | LK_RETRY);
515 
516 	err = fuse_filehandle_get_anyflags(vp, &fufh, cred, pid);
517 	if (err)
518 		goto out;
519 
520 	fdisp_init(&fdi, sizeof(*fli));
521 
522 	fdisp_make_vp(&fdi, op, vp, td, cred);
523 	fli = fdi.indata;
524 	fli->fh = fufh->fh_id;
525 	fli->owner = td->td_proc->p_pid;
526 	fli->lk.start = fl->l_start;
527 	if (fl->l_len != 0)
528 		fli->lk.end = fl->l_start + fl->l_len - 1;
529 	else
530 		fli->lk.end = INT64_MAX;
531 	fli->lk.type = fl->l_type;
532 	fli->lk.pid = td->td_proc->p_pid;
533 
534 	err = fdisp_wait_answ(&fdi);
535 	fdisp_destroy(&fdi);
536 
537 	if (err == 0 && op == FUSE_GETLK) {
538 		flo = fdi.answ;
539 		fl->l_type = flo->lk.type;
540 		fl->l_pid = flo->lk.pid;
541 		if (flo->lk.type != F_UNLCK) {
542 			fl->l_start = flo->lk.start;
543 			if (flo->lk.end == INT64_MAX)
544 				fl->l_len = 0;
545 			else
546 				fl->l_len = flo->lk.end - flo->lk.start + 1;
547 			fl->l_start = flo->lk.start;
548 		}
549 	}
550 
551 out:
552 	VOP_UNLOCK(vp);
553 	return err;
554 }
555 
556 static int
557 fuse_vnop_allocate(struct vop_allocate_args *ap)
558 {
559 	struct vnode *vp = ap->a_vp;
560 	off_t *len = ap->a_len;
561 	off_t *offset = ap->a_offset;
562 	struct ucred *cred = ap->a_cred;
563 	struct fuse_filehandle *fufh;
564 	struct mount *mp = vnode_mount(vp);
565 	struct fuse_dispatcher fdi;
566 	struct fuse_fallocate_in *ffi;
567 	struct uio io;
568 	pid_t pid = curthread->td_proc->p_pid;
569 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
570 	off_t filesize;
571 	int err;
572 
573 	if (fuse_isdeadfs(vp))
574 		return (ENXIO);
575 
576 	switch (vp->v_type) {
577 	case VFIFO:
578 		return (ESPIPE);
579 	case VLNK:
580 	case VREG:
581 		if (vfs_isrdonly(mp))
582 			return (EROFS);
583 		break;
584 	default:
585 		return (ENODEV);
586 	}
587 
588 	if (vfs_isrdonly(mp))
589 		return (EROFS);
590 
591 	if (fsess_not_impl(mp, FUSE_FALLOCATE))
592 		return (EINVAL);
593 
594 	io.uio_offset = *offset;
595 	io.uio_resid = *len;
596 	err = vn_rlimit_fsize(vp, &io, curthread);
597 	if (err)
598 		return (err);
599 
600 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
601 	if (err)
602 		return (err);
603 
604 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
605 
606 	err = fuse_vnode_size(vp, &filesize, cred, curthread);
607 	if (err)
608 		return (err);
609 	fuse_inval_buf_range(vp, filesize, *offset, *offset + *len);
610 
611 	fdisp_init(&fdi, sizeof(*ffi));
612 	fdisp_make_vp(&fdi, FUSE_FALLOCATE, vp, curthread, cred);
613 	ffi = fdi.indata;
614 	ffi->fh = fufh->fh_id;
615 	ffi->offset = *offset;
616 	ffi->length = *len;
617 	ffi->mode = 0;
618 	err = fdisp_wait_answ(&fdi);
619 
620 	if (err == ENOSYS) {
621 		fsess_set_notimpl(mp, FUSE_FALLOCATE);
622 		err = EINVAL;
623 	} else if (err == EOPNOTSUPP) {
624 		/*
625 		 * The file system server does not support FUSE_FALLOCATE with
626 		 * the supplied mode for this particular file.
627 		 */
628 		err = EINVAL;
629 	} else if (!err) {
630 		*offset += *len;
631 		*len = 0;
632 		fuse_vnode_undirty_cached_timestamps(vp, false);
633 		fuse_internal_clear_suid_on_write(vp, cred, curthread);
634 		if (*offset > fvdat->cached_attrs.va_size) {
635 			fuse_vnode_setsize(vp, *offset, false);
636 			getnanouptime(&fvdat->last_local_modify);
637 		}
638 	}
639 
640 	return (err);
641 }
642 
643 /* {
644 	struct vnode *a_vp;
645 	daddr_t a_bn;
646 	struct bufobj **a_bop;
647 	daddr_t *a_bnp;
648 	int *a_runp;
649 	int *a_runb;
650 } */
651 static int
652 fuse_vnop_bmap(struct vop_bmap_args *ap)
653 {
654 	struct vnode *vp = ap->a_vp;
655 	struct bufobj **bo = ap->a_bop;
656 	struct thread *td = curthread;
657 	struct mount *mp;
658 	struct fuse_dispatcher fdi;
659 	struct fuse_bmap_in *fbi;
660 	struct fuse_bmap_out *fbo;
661 	struct fuse_data *data;
662 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
663 	uint64_t biosize;
664 	off_t fsize;
665 	daddr_t lbn = ap->a_bn;
666 	daddr_t *pbn = ap->a_bnp;
667 	int *runp = ap->a_runp;
668 	int *runb = ap->a_runb;
669 	int error = 0;
670 	int maxrun;
671 
672 	if (fuse_isdeadfs(vp)) {
673 		return ENXIO;
674 	}
675 
676 	mp = vnode_mount(vp);
677 	data = fuse_get_mpdata(mp);
678 	biosize = fuse_iosize(vp);
679 	maxrun = MIN(vp->v_mount->mnt_iosize_max / biosize - 1,
680 		data->max_readahead_blocks);
681 
682 	if (bo != NULL)
683 		*bo = &vp->v_bufobj;
684 
685 	/*
686 	 * The FUSE_BMAP operation does not include the runp and runb
687 	 * variables, so we must guess.  Report nonzero contiguous runs so
688 	 * cluster_read will combine adjacent reads.  It's worthwhile to reduce
689 	 * upcalls even if we don't know the true physical layout of the file.
690 	 *
691 	 * FUSE file systems may opt out of read clustering in two ways:
692 	 * * mounting with -onoclusterr
693 	 * * Setting max_readahead <= maxbcachebuf during FUSE_INIT
694 	 */
695 	if (runb != NULL)
696 		*runb = MIN(lbn, maxrun);
697 	if (runp != NULL && maxrun == 0)
698 		*runp = 0;
699 	else if (runp != NULL) {
700 		/*
701 		 * If the file's size is cached, use that value to calculate
702 		 * runp, even if the cache is expired.  runp is only advisory,
703 		 * and the risk of getting it wrong is not worth the cost of
704 		 * another upcall.
705 		 */
706 		if (fvdat->cached_attrs.va_size != VNOVAL)
707 			fsize = fvdat->cached_attrs.va_size;
708 		else
709 			error = fuse_vnode_size(vp, &fsize, td->td_ucred, td);
710 		if (error == 0)
711 			*runp = MIN(MAX(0, fsize / (off_t)biosize - lbn - 1),
712 				    maxrun);
713 		else
714 			*runp = 0;
715 	}
716 
717 	if (fsess_maybe_impl(mp, FUSE_BMAP)) {
718 		fdisp_init(&fdi, sizeof(*fbi));
719 		fdisp_make_vp(&fdi, FUSE_BMAP, vp, td, td->td_ucred);
720 		fbi = fdi.indata;
721 		fbi->block = lbn;
722 		fbi->blocksize = biosize;
723 		error = fdisp_wait_answ(&fdi);
724 		if (error == ENOSYS) {
725 			fdisp_destroy(&fdi);
726 			fsess_set_notimpl(mp, FUSE_BMAP);
727 			error = 0;
728 		} else {
729 			fbo = fdi.answ;
730 			if (error == 0 && pbn != NULL)
731 				*pbn = fbo->block;
732 			fdisp_destroy(&fdi);
733 			return error;
734 		}
735 	}
736 
737 	/* If the daemon doesn't support BMAP, make up a sensible default */
738 	if (pbn != NULL)
739 		*pbn = lbn * btodb(biosize);
740 	return (error);
741 }
742 
743 /*
744     struct vop_close_args {
745 	struct vnode *a_vp;
746 	int  a_fflag;
747 	struct ucred *a_cred;
748 	struct thread *a_td;
749     };
750 */
751 static int
752 fuse_vnop_close(struct vop_close_args *ap)
753 {
754 	struct vnode *vp = ap->a_vp;
755 	struct ucred *cred = ap->a_cred;
756 	int fflag = ap->a_fflag;
757 	struct thread *td = ap->a_td;
758 	pid_t pid = td->td_proc->p_pid;
759 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
760 	int err = 0;
761 
762 	if (fuse_isdeadfs(vp))
763 		return 0;
764 	if (vnode_isdir(vp))
765 		return 0;
766 	if (fflag & IO_NDELAY)
767 		return 0;
768 
769 	err = fuse_flush(vp, cred, pid, fflag);
770 	if (err == 0 && (fvdat->flag & FN_ATIMECHANGE)) {
771 		struct vattr vap;
772 
773 		VATTR_NULL(&vap);
774 		vap.va_atime = fvdat->cached_attrs.va_atime;
775 		err = fuse_internal_setattr(vp, &vap, td, NULL);
776 	}
777 	/* TODO: close the file handle, if we're sure it's no longer used */
778 	if ((fvdat->flag & FN_SIZECHANGE) != 0) {
779 		fuse_vnode_savesize(vp, cred, td->td_proc->p_pid);
780 	}
781 	return err;
782 }
783 
784 /*
785    struct vop_copy_file_range_args {
786 	struct vop_generic_args a_gen;
787 	struct vnode *a_invp;
788 	off_t *a_inoffp;
789 	struct vnode *a_outvp;
790 	off_t *a_outoffp;
791 	size_t *a_lenp;
792 	unsigned int a_flags;
793 	struct ucred *a_incred;
794 	struct ucred *a_outcred;
795 	struct thread *a_fsizetd;
796 }
797  */
798 static int
799 fuse_vnop_copy_file_range(struct vop_copy_file_range_args *ap)
800 {
801 	struct vnode *invp = ap->a_invp;
802 	struct vnode *outvp = ap->a_outvp;
803 	struct mount *mp = vnode_mount(invp);
804 	struct fuse_vnode_data *outfvdat = VTOFUD(outvp);
805 	struct fuse_dispatcher fdi;
806 	struct fuse_filehandle *infufh, *outfufh;
807 	struct fuse_copy_file_range_in *fcfri;
808 	struct ucred *incred = ap->a_incred;
809 	struct ucred *outcred = ap->a_outcred;
810 	struct fuse_write_out *fwo;
811 	struct thread *td;
812 	struct uio io;
813 	off_t outfilesize;
814 	pid_t pid;
815 	int err;
816 
817 	if (mp != vnode_mount(outvp))
818 		goto fallback;
819 
820 	if (incred->cr_uid != outcred->cr_uid)
821 		goto fallback;
822 
823 	if (incred->cr_groups[0] != outcred->cr_groups[0])
824 		goto fallback;
825 
826 	if (fsess_not_impl(mp, FUSE_COPY_FILE_RANGE))
827 		goto fallback;
828 
829 	if (ap->a_fsizetd == NULL)
830 		td = curthread;
831 	else
832 		td = ap->a_fsizetd;
833 	pid = td->td_proc->p_pid;
834 
835 	/* Lock both vnodes, avoiding risk of deadlock. */
836 	do {
837 		err = vn_lock(outvp, LK_EXCLUSIVE);
838 		if (invp == outvp)
839 			break;
840 		if (err == 0) {
841 			err = vn_lock(invp, LK_SHARED | LK_NOWAIT);
842 			if (err == 0)
843 				break;
844 			VOP_UNLOCK(outvp);
845 			err = vn_lock(invp, LK_SHARED);
846 			if (err == 0)
847 				VOP_UNLOCK(invp);
848 		}
849 	} while (err == 0);
850 	if (err != 0)
851 		return (err);
852 
853 	err = fuse_filehandle_getrw(invp, FREAD, &infufh, incred, pid);
854 	if (err)
855 		goto unlock;
856 
857 	err = fuse_filehandle_getrw(outvp, FWRITE, &outfufh, outcred, pid);
858 	if (err)
859 		goto unlock;
860 
861 	if (ap->a_fsizetd) {
862 		io.uio_offset = *ap->a_outoffp;
863 		io.uio_resid = *ap->a_lenp;
864 		err = vn_rlimit_fsize(outvp, &io, ap->a_fsizetd);
865 		if (err)
866 			goto unlock;
867 	}
868 
869 	err = fuse_vnode_size(outvp, &outfilesize, outcred, curthread);
870 	if (err)
871 		goto unlock;
872 
873 	err = fuse_inval_buf_range(outvp, outfilesize, *ap->a_outoffp,
874 		*ap->a_outoffp + *ap->a_lenp);
875 	if (err)
876 		goto unlock;
877 
878 	fdisp_init(&fdi, sizeof(*fcfri));
879 	fdisp_make_vp(&fdi, FUSE_COPY_FILE_RANGE, invp, td, incred);
880 	fcfri = fdi.indata;
881 	fcfri->fh_in = infufh->fh_id;
882 	fcfri->off_in = *ap->a_inoffp;
883 	fcfri->nodeid_out = VTOI(outvp);
884 	fcfri->fh_out = outfufh->fh_id;
885 	fcfri->off_out = *ap->a_outoffp;
886 	fcfri->len = *ap->a_lenp;
887 	fcfri->flags = 0;
888 
889 	err = fdisp_wait_answ(&fdi);
890 	if (err == 0) {
891 		fwo = fdi.answ;
892 		*ap->a_lenp = fwo->size;
893 		*ap->a_inoffp += fwo->size;
894 		*ap->a_outoffp += fwo->size;
895 		fuse_internal_clear_suid_on_write(outvp, outcred, td);
896 		if (*ap->a_outoffp > outfvdat->cached_attrs.va_size) {
897                         fuse_vnode_setsize(outvp, *ap->a_outoffp, false);
898 			getnanouptime(&outfvdat->last_local_modify);
899 		}
900 		fuse_vnode_update(invp, FN_ATIMECHANGE);
901 		fuse_vnode_update(outvp, FN_MTIMECHANGE | FN_CTIMECHANGE);
902 	}
903 	fdisp_destroy(&fdi);
904 
905 unlock:
906 	if (invp != outvp)
907 		VOP_UNLOCK(invp);
908 	VOP_UNLOCK(outvp);
909 
910 	if (err == ENOSYS) {
911 		fsess_set_notimpl(mp, FUSE_COPY_FILE_RANGE);
912 fallback:
913 		err = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp,
914 		    ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags,
915 		    ap->a_incred, ap->a_outcred, ap->a_fsizetd);
916 	}
917 
918 	return (err);
919 }
920 
921 static void
922 fdisp_make_mknod_for_fallback(
923 	struct fuse_dispatcher *fdip,
924 	struct componentname *cnp,
925 	struct vnode *dvp,
926 	uint64_t parentnid,
927 	struct thread *td,
928 	struct ucred *cred,
929 	mode_t mode,
930 	enum fuse_opcode *op)
931 {
932 	struct fuse_mknod_in *fmni;
933 
934 	fdisp_init(fdip, sizeof(*fmni) + cnp->cn_namelen + 1);
935 	*op = FUSE_MKNOD;
936 	fdisp_make(fdip, *op, vnode_mount(dvp), parentnid, td, cred);
937 	fmni = fdip->indata;
938 	fmni->mode = mode;
939 	fmni->rdev = 0;
940 	memcpy((char *)fdip->indata + sizeof(*fmni), cnp->cn_nameptr,
941 	    cnp->cn_namelen);
942 	((char *)fdip->indata)[sizeof(*fmni) + cnp->cn_namelen] = '\0';
943 }
944 /*
945     struct vnop_create_args {
946 	struct vnode *a_dvp;
947 	struct vnode **a_vpp;
948 	struct componentname *a_cnp;
949 	struct vattr *a_vap;
950     };
951 */
952 static int
953 fuse_vnop_create(struct vop_create_args *ap)
954 {
955 	struct vnode *dvp = ap->a_dvp;
956 	struct vnode **vpp = ap->a_vpp;
957 	struct componentname *cnp = ap->a_cnp;
958 	struct vattr *vap = ap->a_vap;
959 	struct thread *td = curthread;
960 	struct ucred *cred = cnp->cn_cred;
961 
962 	struct fuse_data *data;
963 	struct fuse_create_in *fci;
964 	struct fuse_entry_out *feo;
965 	struct fuse_open_out *foo;
966 	struct fuse_dispatcher fdi, fdi2;
967 	struct fuse_dispatcher *fdip = &fdi;
968 	struct fuse_dispatcher *fdip2 = NULL;
969 
970 	int err;
971 
972 	struct mount *mp = vnode_mount(dvp);
973 	data = fuse_get_mpdata(mp);
974 	uint64_t parentnid = VTOFUD(dvp)->nid;
975 	mode_t mode = MAKEIMODE(vap->va_type, vap->va_mode);
976 	enum fuse_opcode op;
977 	int flags;
978 
979 	if (fuse_isdeadfs(dvp))
980 		return ENXIO;
981 
982 	/* FUSE expects sockets to be created with FUSE_MKNOD */
983 	if (vap->va_type == VSOCK)
984 		return fuse_internal_mknod(dvp, vpp, cnp, vap);
985 
986 	/*
987 	 * VOP_CREATE doesn't tell us the open(2) flags, so we guess.  Only a
988 	 * writable mode makes sense, and we might as well include readability
989 	 * too.
990 	 */
991 	flags = O_RDWR;
992 
993 	bzero(&fdi, sizeof(fdi));
994 
995 	if (vap->va_type != VREG)
996 		return (EINVAL);
997 
998 	if (fsess_not_impl(mp, FUSE_CREATE) || vap->va_type == VSOCK) {
999 		/* Fallback to FUSE_MKNOD/FUSE_OPEN */
1000 		fdisp_make_mknod_for_fallback(fdip, cnp, dvp, parentnid, td,
1001 			cred, mode, &op);
1002 	} else {
1003 		/* Use FUSE_CREATE */
1004 		size_t insize;
1005 
1006 		op = FUSE_CREATE;
1007 		fdisp_init(fdip, sizeof(*fci) + cnp->cn_namelen + 1);
1008 		fdisp_make(fdip, op, vnode_mount(dvp), parentnid, td, cred);
1009 		fci = fdip->indata;
1010 		fci->mode = mode;
1011 		fci->flags = O_CREAT | flags;
1012 		if (fuse_libabi_geq(data, 7, 12)) {
1013 			insize = sizeof(*fci);
1014 			fci->umask = td->td_proc->p_pd->pd_cmask;
1015 		} else {
1016 			insize = sizeof(struct fuse_open_in);
1017 		}
1018 
1019 		memcpy((char *)fdip->indata + insize, cnp->cn_nameptr,
1020 		    cnp->cn_namelen);
1021 		((char *)fdip->indata)[insize + cnp->cn_namelen] = '\0';
1022 	}
1023 
1024 	err = fdisp_wait_answ(fdip);
1025 
1026 	if (err) {
1027 		if (err == ENOSYS && op == FUSE_CREATE) {
1028 			fsess_set_notimpl(mp, FUSE_CREATE);
1029 			fdisp_destroy(fdip);
1030 			fdisp_make_mknod_for_fallback(fdip, cnp, dvp,
1031 				parentnid, td, cred, mode, &op);
1032 			err = fdisp_wait_answ(fdip);
1033 		}
1034 		if (err)
1035 			goto out;
1036 	}
1037 
1038 	feo = fdip->answ;
1039 
1040 	if ((err = fuse_internal_checkentry(feo, vap->va_type))) {
1041 		goto out;
1042 	}
1043 
1044 	if (op == FUSE_CREATE) {
1045 		foo = (struct fuse_open_out*)(feo + 1);
1046 	} else {
1047 		/* Issue a separate FUSE_OPEN */
1048 		struct fuse_open_in *foi;
1049 
1050 		fdip2 = &fdi2;
1051 		fdisp_init(fdip2, sizeof(*foi));
1052 		fdisp_make(fdip2, FUSE_OPEN, vnode_mount(dvp), feo->nodeid, td,
1053 			cred);
1054 		foi = fdip2->indata;
1055 		foi->flags = flags;
1056 		err = fdisp_wait_answ(fdip2);
1057 		if (err)
1058 			goto out;
1059 		foo = fdip2->answ;
1060 	}
1061 	err = fuse_vnode_get(mp, feo, feo->nodeid, dvp, vpp, cnp, vap->va_type);
1062 	if (err) {
1063 		struct fuse_release_in *fri;
1064 		uint64_t nodeid = feo->nodeid;
1065 		uint64_t fh_id = foo->fh;
1066 
1067 		fdisp_init(fdip, sizeof(*fri));
1068 		fdisp_make(fdip, FUSE_RELEASE, mp, nodeid, td, cred);
1069 		fri = fdip->indata;
1070 		fri->fh = fh_id;
1071 		fri->flags = flags;
1072 		fuse_insert_callback(fdip->tick, fuse_internal_forget_callback);
1073 		fuse_insert_message(fdip->tick, false);
1074 		goto out;
1075 	}
1076 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnop_create");
1077 	fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid,
1078 		feo->attr_valid_nsec, NULL, true);
1079 
1080 	fuse_filehandle_init(*vpp, FUFH_RDWR, NULL, td, cred, foo);
1081 	fuse_vnode_open(*vpp, foo->open_flags, td);
1082 	/*
1083 	 * Purge the parent's attribute cache because the daemon should've
1084 	 * updated its mtime and ctime
1085 	 */
1086 	fuse_vnode_clear_attr_cache(dvp);
1087 	cache_purge_negative(dvp);
1088 
1089 out:
1090 	if (fdip2)
1091 		fdisp_destroy(fdip2);
1092 	fdisp_destroy(fdip);
1093 	return err;
1094 }
1095 
1096 /*
1097     struct vnop_fdatasync_args {
1098 	struct vop_generic_args a_gen;
1099 	struct vnode * a_vp;
1100 	struct thread * a_td;
1101     };
1102 */
1103 static int
1104 fuse_vnop_fdatasync(struct vop_fdatasync_args *ap)
1105 {
1106 	struct vnode *vp = ap->a_vp;
1107 	struct thread *td = ap->a_td;
1108 	int waitfor = MNT_WAIT;
1109 
1110 	int err = 0;
1111 
1112 	if (fuse_isdeadfs(vp)) {
1113 		return 0;
1114 	}
1115 	if ((err = vop_stdfdatasync_buf(ap)))
1116 		return err;
1117 
1118 	return fuse_internal_fsync(vp, td, waitfor, true);
1119 }
1120 
1121 /*
1122     struct vnop_fsync_args {
1123 	struct vop_generic_args a_gen;
1124 	struct vnode * a_vp;
1125 	int  a_waitfor;
1126 	struct thread * a_td;
1127     };
1128 */
1129 static int
1130 fuse_vnop_fsync(struct vop_fsync_args *ap)
1131 {
1132 	struct vnode *vp = ap->a_vp;
1133 	struct thread *td = ap->a_td;
1134 	int waitfor = ap->a_waitfor;
1135 	int err = 0;
1136 
1137 	if (fuse_isdeadfs(vp)) {
1138 		return 0;
1139 	}
1140 	if ((err = vop_stdfsync(ap)))
1141 		return err;
1142 
1143 	return fuse_internal_fsync(vp, td, waitfor, false);
1144 }
1145 
1146 /*
1147     struct vnop_getattr_args {
1148 	struct vnode *a_vp;
1149 	struct vattr *a_vap;
1150 	struct ucred *a_cred;
1151 	struct thread *a_td;
1152     };
1153 */
1154 static int
1155 fuse_vnop_getattr(struct vop_getattr_args *ap)
1156 {
1157 	struct vnode *vp = ap->a_vp;
1158 	struct vattr *vap = ap->a_vap;
1159 	struct ucred *cred = ap->a_cred;
1160 	struct thread *td = curthread;
1161 
1162 	int err = 0;
1163 	int dataflags;
1164 
1165 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
1166 
1167 	/* Note that we are not bailing out on a dead file system just yet. */
1168 
1169 	if (!(dataflags & FSESS_INITED)) {
1170 		if (!vnode_isvroot(vp)) {
1171 			fdata_set_dead(fuse_get_mpdata(vnode_mount(vp)));
1172 			err = ENOTCONN;
1173 			return err;
1174 		} else {
1175 			goto fake;
1176 		}
1177 	}
1178 	err = fuse_internal_getattr(vp, vap, cred, td);
1179 	if (err == ENOTCONN && vnode_isvroot(vp)) {
1180 		/* see comment in fuse_vfsop_statfs() */
1181 		goto fake;
1182 	} else {
1183 		return err;
1184 	}
1185 
1186 fake:
1187 	bzero(vap, sizeof(*vap));
1188 	vap->va_type = vnode_vtype(vp);
1189 
1190 	return 0;
1191 }
1192 
1193 /*
1194     struct vnop_inactive_args {
1195 	struct vnode *a_vp;
1196     };
1197 */
1198 static int
1199 fuse_vnop_inactive(struct vop_inactive_args *ap)
1200 {
1201 	struct vnode *vp = ap->a_vp;
1202 	struct thread *td = curthread;
1203 
1204 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1205 	struct fuse_filehandle *fufh, *fufh_tmp;
1206 
1207 	int need_flush = 1;
1208 
1209 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1210 		if (need_flush && vp->v_type == VREG) {
1211 			if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) {
1212 				fuse_vnode_savesize(vp, NULL, 0);
1213 			}
1214 			if ((fvdat->flag & FN_REVOKED) != 0)
1215 				fuse_io_invalbuf(vp, td);
1216 			else
1217 				fuse_io_flushbuf(vp, MNT_WAIT, td);
1218 			need_flush = 0;
1219 		}
1220 		fuse_filehandle_close(vp, fufh, td, NULL);
1221 	}
1222 
1223 	if ((fvdat->flag & FN_REVOKED) != 0)
1224 		vrecycle(vp);
1225 
1226 	return 0;
1227 }
1228 
1229 /*
1230     struct vnop_ioctl_args {
1231 	struct vnode *a_vp;
1232 	u_long a_command;
1233 	caddr_t a_data;
1234 	int a_fflag;
1235 	struct ucred *a_cred;
1236 	struct thread *a_td;
1237     };
1238 */
1239 static int
1240 fuse_vnop_ioctl(struct vop_ioctl_args *ap)
1241 {
1242 	struct vnode *vp = ap->a_vp;
1243 	struct mount *mp = vnode_mount(vp);
1244 	struct ucred *cred = ap->a_cred;
1245 	off_t *offp;
1246 	pid_t pid = ap->a_td->td_proc->p_pid;
1247 	int err;
1248 
1249 	switch (ap->a_command) {
1250 	case FIOSEEKDATA:
1251 	case FIOSEEKHOLE:
1252 		/* Call FUSE_LSEEK, if we can, or fall back to vop_stdioctl */
1253 		if (fsess_maybe_impl(mp, FUSE_LSEEK)) {
1254 			int whence;
1255 
1256 			offp = ap->a_data;
1257 			if (ap->a_command == FIOSEEKDATA)
1258 				whence = SEEK_DATA;
1259 			else
1260 				whence = SEEK_HOLE;
1261 
1262 			vn_lock(vp, LK_SHARED | LK_RETRY);
1263 			err = fuse_vnop_do_lseek(vp, ap->a_td, cred, pid, offp,
1264 			    whence);
1265 			VOP_UNLOCK(vp);
1266 		}
1267 		if (fsess_not_impl(mp, FUSE_LSEEK))
1268 			err = vop_stdioctl(ap);
1269 		break;
1270 	default:
1271 		/* TODO: implement FUSE_IOCTL */
1272 		err = ENOTTY;
1273 		break;
1274 	}
1275 	return (err);
1276 }
1277 
1278 
1279 /*
1280     struct vnop_link_args {
1281 	struct vnode *a_tdvp;
1282 	struct vnode *a_vp;
1283 	struct componentname *a_cnp;
1284     };
1285 */
1286 static int
1287 fuse_vnop_link(struct vop_link_args *ap)
1288 {
1289 	struct vnode *vp = ap->a_vp;
1290 	struct vnode *tdvp = ap->a_tdvp;
1291 	struct componentname *cnp = ap->a_cnp;
1292 
1293 	struct vattr *vap = VTOVA(vp);
1294 
1295 	struct fuse_dispatcher fdi;
1296 	struct fuse_entry_out *feo;
1297 	struct fuse_link_in fli;
1298 
1299 	int err;
1300 
1301 	if (fuse_isdeadfs(vp)) {
1302 		return ENXIO;
1303 	}
1304 	if (vnode_mount(tdvp) != vnode_mount(vp)) {
1305 		return EXDEV;
1306 	}
1307 
1308 	/*
1309 	 * This is a seatbelt check to protect naive userspace filesystems from
1310 	 * themselves and the limitations of the FUSE IPC protocol.  If a
1311 	 * filesystem does not allow attribute caching, assume it is capable of
1312 	 * validating that nlink does not overflow.
1313 	 */
1314 	if (vap != NULL && vap->va_nlink >= FUSE_LINK_MAX)
1315 		return EMLINK;
1316 	fli.oldnodeid = VTOI(vp);
1317 
1318 	fdisp_init(&fdi, 0);
1319 	fuse_internal_newentry_makerequest(vnode_mount(tdvp), VTOI(tdvp), cnp,
1320 	    FUSE_LINK, &fli, sizeof(fli), &fdi);
1321 	if ((err = fdisp_wait_answ(&fdi))) {
1322 		goto out;
1323 	}
1324 	feo = fdi.answ;
1325 
1326 	err = fuse_internal_checkentry(feo, vnode_vtype(vp));
1327 	if (!err) {
1328 		/*
1329 		 * Purge the parent's attribute cache because the daemon
1330 		 * should've updated its mtime and ctime
1331 		 */
1332 		fuse_vnode_clear_attr_cache(tdvp);
1333 		fuse_internal_cache_attrs(vp, &feo->attr, feo->attr_valid,
1334 			feo->attr_valid_nsec, NULL, true);
1335 	}
1336 out:
1337 	fdisp_destroy(&fdi);
1338 	return err;
1339 }
1340 
1341 struct fuse_lookup_alloc_arg {
1342 	struct fuse_entry_out *feo;
1343 	struct componentname *cnp;
1344 	uint64_t nid;
1345 	enum vtype vtyp;
1346 };
1347 
1348 /* Callback for vn_get_ino */
1349 static int
1350 fuse_lookup_alloc(struct mount *mp, void *arg, int lkflags, struct vnode **vpp)
1351 {
1352 	struct fuse_lookup_alloc_arg *flaa = arg;
1353 
1354 	return fuse_vnode_get(mp, flaa->feo, flaa->nid, NULL, vpp, flaa->cnp,
1355 		flaa->vtyp);
1356 }
1357 
1358 SDT_PROBE_DEFINE3(fusefs, , vnops, cache_lookup,
1359 	"int", "struct timespec*", "struct timespec*");
1360 /*
1361     struct vnop_lookup_args {
1362 	struct vnodeop_desc *a_desc;
1363 	struct vnode *a_dvp;
1364 	struct vnode **a_vpp;
1365 	struct componentname *a_cnp;
1366     };
1367 */
1368 int
1369 fuse_vnop_lookup(struct vop_lookup_args *ap)
1370 {
1371 	struct vnode *dvp = ap->a_dvp;
1372 	struct vnode **vpp = ap->a_vpp;
1373 	struct componentname *cnp = ap->a_cnp;
1374 	struct thread *td = curthread;
1375 	struct ucred *cred = cnp->cn_cred;
1376 	struct timespec now;
1377 
1378 	int nameiop = cnp->cn_nameiop;
1379 	int flags = cnp->cn_flags;
1380 	int wantparent = flags & (LOCKPARENT | WANTPARENT);
1381 	int islastcn = flags & ISLASTCN;
1382 	struct mount *mp = vnode_mount(dvp);
1383 	struct fuse_data *data = fuse_get_mpdata(mp);
1384 	int default_permissions = data->dataflags & FSESS_DEFAULT_PERMISSIONS;
1385 
1386 	int err = 0;
1387 	int lookup_err = 0;
1388 	struct vnode *vp = NULL;
1389 
1390 	struct fuse_dispatcher fdi;
1391 	bool did_lookup = false;
1392 	struct fuse_entry_out *feo = NULL;
1393 	enum vtype vtyp;	/* vnode type of target */
1394 
1395 	uint64_t nid;
1396 
1397 	if (fuse_isdeadfs(dvp)) {
1398 		*vpp = NULL;
1399 		return ENXIO;
1400 	}
1401 	if (!vnode_isdir(dvp))
1402 		return ENOTDIR;
1403 
1404 	if (islastcn && vfs_isrdonly(mp) && (nameiop != LOOKUP))
1405 		return EROFS;
1406 
1407 	if ((cnp->cn_flags & NOEXECCHECK) != 0)
1408 		cnp->cn_flags &= ~NOEXECCHECK;
1409 	else if ((err = fuse_internal_access(dvp, VEXEC, td, cred)))
1410 		return err;
1411 
1412 	if ((flags & ISDOTDOT) && !(data->dataflags & FSESS_EXPORT_SUPPORT))
1413 	{
1414 		if (!(VTOFUD(dvp)->flag & FN_PARENT_NID)) {
1415 			/*
1416 			 * Since the file system doesn't support ".." lookups,
1417 			 * we have no way to find this entry.
1418 			 */
1419 			return ESTALE;
1420 		}
1421 		nid = VTOFUD(dvp)->parent_nid;
1422 		if (nid == 0)
1423 			return ENOENT;
1424 		/* .. is obviously a directory */
1425 		vtyp = VDIR;
1426 	} else if (cnp->cn_namelen == 1 && *(cnp->cn_nameptr) == '.') {
1427 		nid = VTOI(dvp);
1428 		/* . is obviously a directory */
1429 		vtyp = VDIR;
1430 	} else {
1431 		struct timespec timeout;
1432 		int ncpticks; /* here to accommodate for API contract */
1433 
1434 		err = cache_lookup(dvp, vpp, cnp, &timeout, &ncpticks);
1435 		getnanouptime(&now);
1436 		SDT_PROBE3(fusefs, , vnops, cache_lookup, err, &timeout, &now);
1437 		switch (err) {
1438 		case -1:		/* positive match */
1439 			if (timespeccmp(&timeout, &now, >)) {
1440 				counter_u64_add(fuse_lookup_cache_hits, 1);
1441 			} else {
1442 				/* Cache timeout */
1443 				counter_u64_add(fuse_lookup_cache_misses, 1);
1444 				bintime_clear(
1445 					&VTOFUD(*vpp)->entry_cache_timeout);
1446 				cache_purge(*vpp);
1447 				if (dvp != *vpp)
1448 					vput(*vpp);
1449 				else
1450 					vrele(*vpp);
1451 				*vpp = NULL;
1452 				break;
1453 			}
1454 			return 0;
1455 
1456 		case 0:		/* no match in cache */
1457 			counter_u64_add(fuse_lookup_cache_misses, 1);
1458 			break;
1459 
1460 		case ENOENT:		/* negative match */
1461 			if (timespeccmp(&timeout, &now, <=)) {
1462 				/* Cache timeout */
1463 				cache_purge_negative(dvp);
1464 				break;
1465 			}
1466 			/* fall through */
1467 		default:
1468 			return err;
1469 		}
1470 
1471 		fdisp_init(&fdi, cnp->cn_namelen + 1);
1472 		fdisp_make(&fdi, FUSE_LOOKUP, mp, VTOI(dvp), td, cred);
1473 
1474 		memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
1475 		((char *)fdi.indata)[cnp->cn_namelen] = '\0';
1476 		lookup_err = fdisp_wait_answ(&fdi);
1477 		did_lookup = true;
1478 
1479 		if (!lookup_err) {
1480 			/* lookup call succeeded */
1481 			feo = (struct fuse_entry_out *)fdi.answ;
1482 			nid = feo->nodeid;
1483 			if (nid == 0) {
1484 				/* zero nodeid means ENOENT and cache it */
1485 				struct timespec timeout;
1486 
1487 				fdi.answ_stat = ENOENT;
1488 				lookup_err = ENOENT;
1489 				if (cnp->cn_flags & MAKEENTRY) {
1490 					fuse_validity_2_timespec(feo, &timeout);
1491 					/* Use the same entry_time for .. as for
1492 					 * the file itself.  That doesn't honor
1493 					 * exactly what the fuse server tells
1494 					 * us, but to do otherwise would require
1495 					 * another cache lookup at this point.
1496 					 */
1497 					struct timespec *dtsp = NULL;
1498 					cache_enter_time(dvp, *vpp, cnp,
1499 						&timeout, dtsp);
1500 				}
1501 			}
1502 			vtyp = IFTOVT(feo->attr.mode);
1503 		}
1504 		if (lookup_err && (!fdi.answ_stat || lookup_err != ENOENT)) {
1505 			fdisp_destroy(&fdi);
1506 			return lookup_err;
1507 		}
1508 	}
1509 	/* lookup_err, if non-zero, must be ENOENT at this point */
1510 
1511 	if (lookup_err) {
1512 		/* Entry not found */
1513 		if ((nameiop == CREATE || nameiop == RENAME) && islastcn) {
1514 			if (default_permissions)
1515 				err = fuse_internal_access(dvp, VWRITE, td,
1516 				    cred);
1517 			else
1518 				err = 0;
1519 			if (!err) {
1520 				/*
1521 				 * Set the SAVENAME flag to hold onto the
1522 				 * pathname for use later in VOP_CREATE or
1523 				 * VOP_RENAME.
1524 				 */
1525 				cnp->cn_flags |= SAVENAME;
1526 
1527 				err = EJUSTRETURN;
1528 			}
1529 		} else {
1530 			err = ENOENT;
1531 		}
1532 	} else {
1533 		/* Entry was found */
1534 		if (flags & ISDOTDOT) {
1535 			struct fuse_lookup_alloc_arg flaa;
1536 
1537 			flaa.nid = nid;
1538 			flaa.feo = feo;
1539 			flaa.cnp = cnp;
1540 			flaa.vtyp = vtyp;
1541 			err = vn_vget_ino_gen(dvp, fuse_lookup_alloc, &flaa, 0,
1542 				&vp);
1543 			*vpp = vp;
1544 		} else if (nid == VTOI(dvp)) {
1545 			vref(dvp);
1546 			*vpp = dvp;
1547 		} else {
1548 			struct fuse_vnode_data *fvdat;
1549 
1550 			err = fuse_vnode_get(vnode_mount(dvp), feo, nid, dvp,
1551 			    &vp, cnp, vtyp);
1552 			if (err)
1553 				goto out;
1554 			*vpp = vp;
1555 			fvdat = VTOFUD(vp);
1556 
1557 			MPASS(feo != NULL);
1558 			if (timespeccmp(&now, &fvdat->last_local_modify, >)) {
1559 				/*
1560 				 * Attributes from the server are definitely
1561 				 * newer than the last attributes we sent to
1562 				 * the server, so cache them.
1563 				 */
1564 				fuse_internal_cache_attrs(*vpp, &feo->attr,
1565 					feo->attr_valid, feo->attr_valid_nsec,
1566 					NULL, true);
1567 			}
1568 			fuse_validity_2_bintime(feo->entry_valid,
1569 				feo->entry_valid_nsec,
1570 				&fvdat->entry_cache_timeout);
1571 
1572 			if ((nameiop == DELETE || nameiop == RENAME) &&
1573 				islastcn && default_permissions)
1574 			{
1575 				struct vattr dvattr;
1576 
1577 				err = fuse_internal_access(dvp, VWRITE, td,
1578 					cred);
1579 				if (err != 0)
1580 					goto out;
1581 				/*
1582 				 * if the parent's sticky bit is set, check
1583 				 * whether we're allowed to remove the file.
1584 				 * Need to figure out the vnode locking to make
1585 				 * this work.
1586 				 */
1587 				fuse_internal_getattr(dvp, &dvattr, cred, td);
1588 				if ((dvattr.va_mode & S_ISTXT) &&
1589 					fuse_internal_access(dvp, VADMIN, td,
1590 						cred) &&
1591 					fuse_internal_access(*vpp, VADMIN, td,
1592 						cred)) {
1593 					err = EPERM;
1594 					goto out;
1595 				}
1596 			}
1597 
1598 			if (islastcn && (
1599 				(nameiop == DELETE) ||
1600 				(nameiop == RENAME && wantparent))) {
1601 				cnp->cn_flags |= SAVENAME;
1602 			}
1603 		}
1604 	}
1605 out:
1606 	if (err) {
1607 		if (vp != NULL && dvp != vp)
1608 			vput(vp);
1609 		else if (vp != NULL)
1610 			vrele(vp);
1611 		*vpp = NULL;
1612 	}
1613 	if (did_lookup)
1614 		fdisp_destroy(&fdi);
1615 
1616 	return err;
1617 }
1618 
1619 /*
1620     struct vnop_mkdir_args {
1621 	struct vnode *a_dvp;
1622 	struct vnode **a_vpp;
1623 	struct componentname *a_cnp;
1624 	struct vattr *a_vap;
1625     };
1626 */
1627 static int
1628 fuse_vnop_mkdir(struct vop_mkdir_args *ap)
1629 {
1630 	struct vnode *dvp = ap->a_dvp;
1631 	struct vnode **vpp = ap->a_vpp;
1632 	struct componentname *cnp = ap->a_cnp;
1633 	struct vattr *vap = ap->a_vap;
1634 
1635 	struct fuse_mkdir_in fmdi;
1636 
1637 	if (fuse_isdeadfs(dvp)) {
1638 		return ENXIO;
1639 	}
1640 	fmdi.mode = MAKEIMODE(vap->va_type, vap->va_mode);
1641 	fmdi.umask = curthread->td_proc->p_pd->pd_cmask;
1642 
1643 	return (fuse_internal_newentry(dvp, vpp, cnp, FUSE_MKDIR, &fmdi,
1644 	    sizeof(fmdi), VDIR));
1645 }
1646 
1647 /*
1648     struct vnop_mknod_args {
1649 	struct vnode *a_dvp;
1650 	struct vnode **a_vpp;
1651 	struct componentname *a_cnp;
1652 	struct vattr *a_vap;
1653     };
1654 */
1655 static int
1656 fuse_vnop_mknod(struct vop_mknod_args *ap)
1657 {
1658 
1659 	struct vnode *dvp = ap->a_dvp;
1660 	struct vnode **vpp = ap->a_vpp;
1661 	struct componentname *cnp = ap->a_cnp;
1662 	struct vattr *vap = ap->a_vap;
1663 
1664 	if (fuse_isdeadfs(dvp))
1665 		return ENXIO;
1666 
1667 	return fuse_internal_mknod(dvp, vpp, cnp, vap);
1668 }
1669 
1670 /*
1671     struct vop_open_args {
1672 	struct vnode *a_vp;
1673 	int  a_mode;
1674 	struct ucred *a_cred;
1675 	struct thread *a_td;
1676 	int a_fdidx; / struct file *a_fp;
1677     };
1678 */
1679 static int
1680 fuse_vnop_open(struct vop_open_args *ap)
1681 {
1682 	struct vnode *vp = ap->a_vp;
1683 	int a_mode = ap->a_mode;
1684 	struct thread *td = ap->a_td;
1685 	struct ucred *cred = ap->a_cred;
1686 	pid_t pid = td->td_proc->p_pid;
1687 
1688 	if (fuse_isdeadfs(vp))
1689 		return ENXIO;
1690 	if (vp->v_type == VCHR || vp->v_type == VBLK || vp->v_type == VFIFO)
1691 		return (EOPNOTSUPP);
1692 	if ((a_mode & (FREAD | FWRITE | FEXEC)) == 0)
1693 		return EINVAL;
1694 
1695 	if (fuse_filehandle_validrw(vp, a_mode, cred, pid)) {
1696 		fuse_vnode_open(vp, 0, td);
1697 		return 0;
1698 	}
1699 
1700 	return fuse_filehandle_open(vp, a_mode, NULL, td, cred);
1701 }
1702 
1703 static int
1704 fuse_vnop_pathconf(struct vop_pathconf_args *ap)
1705 {
1706 	struct vnode *vp = ap->a_vp;
1707 	struct mount *mp;
1708 
1709 	switch (ap->a_name) {
1710 	case _PC_FILESIZEBITS:
1711 		*ap->a_retval = 64;
1712 		return (0);
1713 	case _PC_NAME_MAX:
1714 		*ap->a_retval = NAME_MAX;
1715 		return (0);
1716 	case _PC_LINK_MAX:
1717 		*ap->a_retval = MIN(LONG_MAX, FUSE_LINK_MAX);
1718 		return (0);
1719 	case _PC_SYMLINK_MAX:
1720 		*ap->a_retval = MAXPATHLEN;
1721 		return (0);
1722 	case _PC_NO_TRUNC:
1723 		*ap->a_retval = 1;
1724 		return (0);
1725 	case _PC_MIN_HOLE_SIZE:
1726 		/*
1727 		 * The FUSE protocol provides no mechanism for a server to
1728 		 * report _PC_MIN_HOLE_SIZE.  It's a protocol bug.  Instead,
1729 		 * return EINVAL if the server does not support FUSE_LSEEK, or
1730 		 * 1 if it does.
1731 		 */
1732 		mp = vnode_mount(vp);
1733 		if (!fsess_is_impl(mp, FUSE_LSEEK) &&
1734 		    !fsess_not_impl(mp, FUSE_LSEEK)) {
1735 			off_t offset = 0;
1736 
1737 			/* Issue a FUSE_LSEEK to find out if it's implemented */
1738 			fuse_vnop_do_lseek(vp, curthread, curthread->td_ucred,
1739 			    curthread->td_proc->p_pid, &offset, SEEK_DATA);
1740 		}
1741 
1742 		if (fsess_is_impl(mp, FUSE_LSEEK)) {
1743 			*ap->a_retval = 1;
1744 			return (0);
1745 		} else {
1746 			/*
1747 			 * Probably FUSE_LSEEK is not implemented.  It might
1748 			 * be, if the FUSE_LSEEK above returned an error like
1749 			 * EACCES, but in that case we can't tell, so it's
1750 			 * safest to report EINVAL anyway.
1751 			 */
1752 			return (EINVAL);
1753 		}
1754 	default:
1755 		return (vop_stdpathconf(ap));
1756 	}
1757 }
1758 
1759 SDT_PROBE_DEFINE3(fusefs, , vnops, filehandles_closed, "struct vnode*",
1760     "struct uio*", "struct ucred*");
1761 /*
1762     struct vnop_read_args {
1763 	struct vnode *a_vp;
1764 	struct uio *a_uio;
1765 	int  a_ioflag;
1766 	struct ucred *a_cred;
1767     };
1768 */
1769 static int
1770 fuse_vnop_read(struct vop_read_args *ap)
1771 {
1772 	struct vnode *vp = ap->a_vp;
1773 	struct uio *uio = ap->a_uio;
1774 	int ioflag = ap->a_ioflag;
1775 	struct ucred *cred = ap->a_cred;
1776 	pid_t pid = curthread->td_proc->p_pid;
1777 	struct fuse_filehandle *fufh;
1778 	int err;
1779 	bool closefufh = false, directio;
1780 
1781 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
1782 
1783 	if (fuse_isdeadfs(vp)) {
1784 		return ENXIO;
1785 	}
1786 
1787 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
1788 		ioflag |= IO_DIRECT;
1789 	}
1790 
1791 	err = fuse_filehandle_getrw(vp, FREAD, &fufh, cred, pid);
1792 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
1793 		/*
1794 		 * nfsd will do I/O without first doing VOP_OPEN.  We
1795 		 * must implicitly open the file here
1796 		 */
1797 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1798 		closefufh = true;
1799 	}
1800 	if (err) {
1801 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
1802 		return err;
1803 	}
1804 
1805 	/*
1806          * Ideally, when the daemon asks for direct io at open time, the
1807          * standard file flag should be set according to this, so that would
1808          * just change the default mode, which later on could be changed via
1809          * fcntl(2).
1810          * But this doesn't work, the O_DIRECT flag gets cleared at some point
1811          * (don't know where). So to make any use of the Fuse direct_io option,
1812          * we hardwire it into the file's private data (similarly to Linux,
1813          * btw.).
1814          */
1815 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
1816 
1817 	fuse_vnode_update(vp, FN_ATIMECHANGE);
1818 	if (directio) {
1819 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct read of vnode");
1820 		err = fuse_read_directbackend(vp, uio, cred, fufh);
1821 	} else {
1822 		SDT_PROBE2(fusefs, , vnops, trace, 1, "buffered read of vnode");
1823 		err = fuse_read_biobackend(vp, uio, ioflag, cred, fufh, pid);
1824 	}
1825 
1826 	if (closefufh)
1827 		fuse_filehandle_close(vp, fufh, curthread, cred);
1828 
1829 	return (err);
1830 }
1831 
1832 /*
1833     struct vnop_readdir_args {
1834 	struct vnode *a_vp;
1835 	struct uio *a_uio;
1836 	struct ucred *a_cred;
1837 	int *a_eofflag;
1838 	int *a_ncookies;
1839 	uint64_t **a_cookies;
1840     };
1841 */
1842 static int
1843 fuse_vnop_readdir(struct vop_readdir_args *ap)
1844 {
1845 	struct vnode *vp = ap->a_vp;
1846 	struct uio *uio = ap->a_uio;
1847 	struct ucred *cred = ap->a_cred;
1848 	struct fuse_filehandle *fufh = NULL;
1849 	struct mount *mp = vnode_mount(vp);
1850 	struct fuse_iov cookediov;
1851 	int err = 0;
1852 	uint64_t *cookies;
1853 	ssize_t tresid;
1854 	int ncookies;
1855 	bool closefufh = false;
1856 	pid_t pid = curthread->td_proc->p_pid;
1857 
1858 	if (ap->a_eofflag)
1859 		*ap->a_eofflag = 0;
1860 	if (fuse_isdeadfs(vp)) {
1861 		return ENXIO;
1862 	}
1863 	if (				/* XXXIP ((uio_iovcnt(uio) > 1)) || */
1864 	    (uio_resid(uio) < sizeof(struct dirent))) {
1865 		return EINVAL;
1866 	}
1867 
1868 	tresid = uio->uio_resid;
1869 	err = fuse_filehandle_get_dir(vp, &fufh, cred, pid);
1870 	if (err == EBADF && mp->mnt_flag & MNT_EXPORTED) {
1871 		KASSERT(fuse_get_mpdata(mp)->dataflags
1872 				& FSESS_NO_OPENDIR_SUPPORT,
1873 			("FUSE file systems that don't set "
1874 			 "FUSE_NO_OPENDIR_SUPPORT should not be exported"));
1875 		/*
1876 		 * nfsd will do VOP_READDIR without first doing VOP_OPEN.  We
1877 		 * must implicitly open the directory here.
1878 		 */
1879 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1880 		closefufh = true;
1881 	}
1882 	if (err)
1883 		return (err);
1884 	if (ap->a_ncookies != NULL) {
1885 		ncookies = uio->uio_resid /
1886 			(offsetof(struct dirent, d_name) + 4) + 1;
1887 		cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
1888 		*ap->a_ncookies = ncookies;
1889 		*ap->a_cookies = cookies;
1890 	} else {
1891 		ncookies = 0;
1892 		cookies = NULL;
1893 	}
1894 #define DIRCOOKEDSIZE FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + MAXNAMLEN + 1)
1895 	fiov_init(&cookediov, DIRCOOKEDSIZE);
1896 
1897 	err = fuse_internal_readdir(vp, uio, fufh, &cookediov,
1898 		&ncookies, cookies);
1899 
1900 	fiov_teardown(&cookediov);
1901 	if (closefufh)
1902 		fuse_filehandle_close(vp, fufh, curthread, cred);
1903 
1904 	if (ap->a_ncookies != NULL) {
1905 		if (err == 0) {
1906 			*ap->a_ncookies -= ncookies;
1907 		} else {
1908 			free(*ap->a_cookies, M_TEMP);
1909 			*ap->a_ncookies = 0;
1910 			*ap->a_cookies = NULL;
1911 		}
1912 	}
1913 	if (err == 0 && tresid == uio->uio_resid)
1914 		*ap->a_eofflag = 1;
1915 
1916 	return err;
1917 }
1918 
1919 /*
1920     struct vnop_readlink_args {
1921 	struct vnode *a_vp;
1922 	struct uio *a_uio;
1923 	struct ucred *a_cred;
1924     };
1925 */
1926 static int
1927 fuse_vnop_readlink(struct vop_readlink_args *ap)
1928 {
1929 	struct vnode *vp = ap->a_vp;
1930 	struct uio *uio = ap->a_uio;
1931 	struct ucred *cred = ap->a_cred;
1932 
1933 	struct fuse_dispatcher fdi;
1934 	int err;
1935 
1936 	if (fuse_isdeadfs(vp)) {
1937 		return ENXIO;
1938 	}
1939 	if (!vnode_islnk(vp)) {
1940 		return EINVAL;
1941 	}
1942 	fdisp_init(&fdi, 0);
1943 	err = fdisp_simple_putget_vp(&fdi, FUSE_READLINK, vp, curthread, cred);
1944 	if (err) {
1945 		goto out;
1946 	}
1947 	if (((char *)fdi.answ)[0] == '/' &&
1948 	    fuse_get_mpdata(vnode_mount(vp))->dataflags & FSESS_PUSH_SYMLINKS_IN) {
1949 		char *mpth = vnode_mount(vp)->mnt_stat.f_mntonname;
1950 
1951 		err = uiomove(mpth, strlen(mpth), uio);
1952 	}
1953 	if (!err) {
1954 		err = uiomove(fdi.answ, fdi.iosize, uio);
1955 	}
1956 out:
1957 	fdisp_destroy(&fdi);
1958 	return err;
1959 }
1960 
1961 /*
1962     struct vnop_reclaim_args {
1963 	struct vnode *a_vp;
1964     };
1965 */
1966 static int
1967 fuse_vnop_reclaim(struct vop_reclaim_args *ap)
1968 {
1969 	struct vnode *vp = ap->a_vp;
1970 	struct thread *td = curthread;
1971 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1972 	struct fuse_filehandle *fufh, *fufh_tmp;
1973 
1974 	if (!fvdat) {
1975 		panic("FUSE: no vnode data during recycling");
1976 	}
1977 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1978 		printf("FUSE: vnode being reclaimed with open fufh "
1979 			"(type=%#x)", fufh->fufh_type);
1980 		fuse_filehandle_close(vp, fufh, td, NULL);
1981 	}
1982 
1983 	if (VTOI(vp) == 1) {
1984 		/*
1985 		 * Don't send FUSE_FORGET for the root inode, because
1986 		 * we never send FUSE_LOOKUP for it (see
1987 		 * fuse_vfsop_root) and we don't want the server to see
1988 		 * mismatched lookup counts.
1989 		 */
1990 		struct fuse_data *data;
1991 		struct vnode *vroot;
1992 
1993 		data = fuse_get_mpdata(vnode_mount(vp));
1994 		FUSE_LOCK();
1995 		vroot = data->vroot;
1996 		data->vroot = NULL;
1997 		FUSE_UNLOCK();
1998 		if (vroot)
1999 			vrele(vroot);
2000 	} else if (!fuse_isdeadfs(vp) && fvdat->nlookup > 0) {
2001 		fuse_internal_forget_send(vnode_mount(vp), td, NULL, VTOI(vp),
2002 		    fvdat->nlookup);
2003 	}
2004 	cache_purge(vp);
2005 	vfs_hash_remove(vp);
2006 	fuse_vnode_destroy(vp);
2007 
2008 	return 0;
2009 }
2010 
2011 /*
2012     struct vnop_remove_args {
2013 	struct vnode *a_dvp;
2014 	struct vnode *a_vp;
2015 	struct componentname *a_cnp;
2016     };
2017 */
2018 static int
2019 fuse_vnop_remove(struct vop_remove_args *ap)
2020 {
2021 	struct vnode *dvp = ap->a_dvp;
2022 	struct vnode *vp = ap->a_vp;
2023 	struct componentname *cnp = ap->a_cnp;
2024 
2025 	int err;
2026 
2027 	if (fuse_isdeadfs(vp)) {
2028 		return ENXIO;
2029 	}
2030 	if (vnode_isdir(vp)) {
2031 		return EPERM;
2032 	}
2033 
2034 	err = fuse_internal_remove(dvp, vp, cnp, FUSE_UNLINK);
2035 
2036 	return err;
2037 }
2038 
2039 /*
2040     struct vnop_rename_args {
2041 	struct vnode *a_fdvp;
2042 	struct vnode *a_fvp;
2043 	struct componentname *a_fcnp;
2044 	struct vnode *a_tdvp;
2045 	struct vnode *a_tvp;
2046 	struct componentname *a_tcnp;
2047     };
2048 */
2049 static int
2050 fuse_vnop_rename(struct vop_rename_args *ap)
2051 {
2052 	struct vnode *fdvp = ap->a_fdvp;
2053 	struct vnode *fvp = ap->a_fvp;
2054 	struct componentname *fcnp = ap->a_fcnp;
2055 	struct vnode *tdvp = ap->a_tdvp;
2056 	struct vnode *tvp = ap->a_tvp;
2057 	struct componentname *tcnp = ap->a_tcnp;
2058 	struct fuse_data *data;
2059 	bool newparent = fdvp != tdvp;
2060 	bool isdir = fvp->v_type == VDIR;
2061 	int err = 0;
2062 
2063 	if (fuse_isdeadfs(fdvp)) {
2064 		return ENXIO;
2065 	}
2066 	if (fvp->v_mount != tdvp->v_mount ||
2067 	    (tvp && fvp->v_mount != tvp->v_mount)) {
2068 		SDT_PROBE2(fusefs, , vnops, trace, 1, "cross-device rename");
2069 		err = EXDEV;
2070 		goto out;
2071 	}
2072 	cache_purge(fvp);
2073 
2074 	/*
2075 	 * FUSE library is expected to check if target directory is not
2076 	 * under the source directory in the file system tree.
2077 	 * Linux performs this check at VFS level.
2078 	 */
2079 	/*
2080 	 * If source is a directory, and it will get a new parent, user must
2081 	 * have write permission to it, so ".." can be modified.
2082 	 */
2083 	data = fuse_get_mpdata(vnode_mount(tdvp));
2084 	if (data->dataflags & FSESS_DEFAULT_PERMISSIONS && isdir && newparent) {
2085 		err = fuse_internal_access(fvp, VWRITE,
2086 			curthread, tcnp->cn_cred);
2087 		if (err)
2088 			goto out;
2089 	}
2090 	sx_xlock(&data->rename_lock);
2091 	err = fuse_internal_rename(fdvp, fcnp, tdvp, tcnp);
2092 	if (err == 0) {
2093 		if (tdvp != fdvp)
2094 			fuse_vnode_setparent(fvp, tdvp);
2095 		if (tvp != NULL)
2096 			fuse_vnode_setparent(tvp, NULL);
2097 	}
2098 	sx_unlock(&data->rename_lock);
2099 
2100 	if (tvp != NULL && tvp != fvp) {
2101 		cache_purge(tvp);
2102 	}
2103 	if (vnode_isdir(fvp)) {
2104 		if (((tvp != NULL) && vnode_isdir(tvp)) || vnode_isdir(fvp)) {
2105 			cache_purge(tdvp);
2106 		}
2107 		cache_purge(fdvp);
2108 	}
2109 out:
2110 	if (tdvp == tvp) {
2111 		vrele(tdvp);
2112 	} else {
2113 		vput(tdvp);
2114 	}
2115 	if (tvp != NULL) {
2116 		vput(tvp);
2117 	}
2118 	vrele(fdvp);
2119 	vrele(fvp);
2120 
2121 	return err;
2122 }
2123 
2124 /*
2125     struct vnop_rmdir_args {
2126 	    struct vnode *a_dvp;
2127 	    struct vnode *a_vp;
2128 	    struct componentname *a_cnp;
2129     } *ap;
2130 */
2131 static int
2132 fuse_vnop_rmdir(struct vop_rmdir_args *ap)
2133 {
2134 	struct vnode *dvp = ap->a_dvp;
2135 	struct vnode *vp = ap->a_vp;
2136 
2137 	int err;
2138 
2139 	if (fuse_isdeadfs(vp)) {
2140 		return ENXIO;
2141 	}
2142 	if (VTOFUD(vp) == VTOFUD(dvp)) {
2143 		return EINVAL;
2144 	}
2145 	err = fuse_internal_remove(dvp, vp, ap->a_cnp, FUSE_RMDIR);
2146 
2147 	return err;
2148 }
2149 
2150 /*
2151     struct vnop_setattr_args {
2152 	struct vnode *a_vp;
2153 	struct vattr *a_vap;
2154 	struct ucred *a_cred;
2155 	struct thread *a_td;
2156     };
2157 */
2158 static int
2159 fuse_vnop_setattr(struct vop_setattr_args *ap)
2160 {
2161 	struct vnode *vp = ap->a_vp;
2162 	struct vattr *vap = ap->a_vap;
2163 	struct ucred *cred = ap->a_cred;
2164 	struct thread *td = curthread;
2165 	struct mount *mp;
2166 	struct fuse_data *data;
2167 	struct vattr old_va;
2168 	int dataflags;
2169 	int err = 0, err2;
2170 	accmode_t accmode = 0;
2171 	bool checkperm;
2172 	bool drop_suid = false;
2173 	gid_t cr_gid;
2174 
2175 	mp = vnode_mount(vp);
2176 	data = fuse_get_mpdata(mp);
2177 	dataflags = data->dataflags;
2178 	checkperm = dataflags & FSESS_DEFAULT_PERMISSIONS;
2179 	if (cred->cr_ngroups > 0)
2180 		cr_gid = cred->cr_groups[0];
2181 	else
2182 		cr_gid = 0;
2183 
2184 	if (fuse_isdeadfs(vp)) {
2185 		return ENXIO;
2186 	}
2187 
2188 	if (vap->va_uid != (uid_t)VNOVAL) {
2189 		if (checkperm) {
2190 			/* Only root may change a file's owner */
2191 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2192 			if (err) {
2193 				/* As a special case, allow the null chown */
2194 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2195 					td);
2196 				if (err2)
2197 					return (err2);
2198 				if (vap->va_uid != old_va.va_uid)
2199 					return err;
2200 				else
2201 					accmode |= VADMIN;
2202 				drop_suid = true;
2203 			} else
2204 				accmode |= VADMIN;
2205 		} else
2206 			accmode |= VADMIN;
2207 	}
2208 	if (vap->va_gid != (gid_t)VNOVAL) {
2209 		if (checkperm && priv_check_cred(cred, PRIV_VFS_CHOWN))
2210 			drop_suid = true;
2211 		if (checkperm && !groupmember(vap->va_gid, cred))
2212 		{
2213 			/*
2214 			 * Non-root users may only chgrp to one of their own
2215 			 * groups
2216 			 */
2217 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2218 			if (err) {
2219 				/* As a special case, allow the null chgrp */
2220 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2221 					td);
2222 				if (err2)
2223 					return (err2);
2224 				if (vap->va_gid != old_va.va_gid)
2225 					return err;
2226 				accmode |= VADMIN;
2227 			} else
2228 				accmode |= VADMIN;
2229 		} else
2230 			accmode |= VADMIN;
2231 	}
2232 	if (vap->va_size != VNOVAL) {
2233 		switch (vp->v_type) {
2234 		case VDIR:
2235 			return (EISDIR);
2236 		case VLNK:
2237 		case VREG:
2238 			if (vfs_isrdonly(mp))
2239 				return (EROFS);
2240 			break;
2241 		default:
2242 			/*
2243 			 * According to POSIX, the result is unspecified
2244 			 * for file types other than regular files,
2245 			 * directories and shared memory objects.  We
2246 			 * don't support shared memory objects in the file
2247 			 * system, and have dubious support for truncating
2248 			 * symlinks.  Just ignore the request in other cases.
2249 			 */
2250 			return (0);
2251 		}
2252 		/* Don't set accmode.  Permission to trunc is checked upstack */
2253 	}
2254 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
2255 		if (vap->va_vaflags & VA_UTIMES_NULL)
2256 			accmode |= VWRITE;
2257 		else
2258 			accmode |= VADMIN;
2259 	}
2260 	if (drop_suid) {
2261 		if (vap->va_mode != (mode_t)VNOVAL)
2262 			vap->va_mode &= ~(S_ISUID | S_ISGID);
2263 		else {
2264 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2265 			if (err)
2266 				return (err);
2267 			vap->va_mode = old_va.va_mode & ~(S_ISUID | S_ISGID);
2268 		}
2269 	}
2270 	if (vap->va_mode != (mode_t)VNOVAL) {
2271 		/* Only root may set the sticky bit on non-directories */
2272 		if (checkperm && vp->v_type != VDIR && (vap->va_mode & S_ISTXT)
2273 		    && priv_check_cred(cred, PRIV_VFS_STICKYFILE))
2274 			return EFTYPE;
2275 		if (checkperm && (vap->va_mode & S_ISGID)) {
2276 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2277 			if (err)
2278 				return (err);
2279 			if (!groupmember(old_va.va_gid, cred)) {
2280 				err = priv_check_cred(cred, PRIV_VFS_SETGID);
2281 				if (err)
2282 					return (err);
2283 			}
2284 		}
2285 		accmode |= VADMIN;
2286 	}
2287 
2288 	if (vfs_isrdonly(mp))
2289 		return EROFS;
2290 
2291 	if (checkperm) {
2292 		err = fuse_internal_access(vp, accmode, td, cred);
2293 	} else {
2294 		err = 0;
2295 	}
2296 	if (err)
2297 		return err;
2298 	else
2299 		return fuse_internal_setattr(vp, vap, td, cred);
2300 }
2301 
2302 /*
2303     struct vnop_strategy_args {
2304 	struct vnode *a_vp;
2305 	struct buf *a_bp;
2306     };
2307 */
2308 static int
2309 fuse_vnop_strategy(struct vop_strategy_args *ap)
2310 {
2311 	struct vnode *vp = ap->a_vp;
2312 	struct buf *bp = ap->a_bp;
2313 
2314 	if (!vp || fuse_isdeadfs(vp)) {
2315 		bp->b_ioflags |= BIO_ERROR;
2316 		bp->b_error = ENXIO;
2317 		bufdone(bp);
2318 		return 0;
2319 	}
2320 
2321 	/*
2322 	 * VOP_STRATEGY always returns zero and signals error via bp->b_ioflags.
2323 	 * fuse_io_strategy sets bp's error fields
2324 	 */
2325 	(void)fuse_io_strategy(vp, bp);
2326 
2327 	return 0;
2328 }
2329 
2330 /*
2331     struct vnop_symlink_args {
2332 	struct vnode *a_dvp;
2333 	struct vnode **a_vpp;
2334 	struct componentname *a_cnp;
2335 	struct vattr *a_vap;
2336 	char *a_target;
2337     };
2338 */
2339 static int
2340 fuse_vnop_symlink(struct vop_symlink_args *ap)
2341 {
2342 	struct vnode *dvp = ap->a_dvp;
2343 	struct vnode **vpp = ap->a_vpp;
2344 	struct componentname *cnp = ap->a_cnp;
2345 	const char *target = ap->a_target;
2346 
2347 	struct fuse_dispatcher fdi;
2348 
2349 	int err;
2350 	size_t len;
2351 
2352 	if (fuse_isdeadfs(dvp)) {
2353 		return ENXIO;
2354 	}
2355 	/*
2356 	 * Unlike the other creator type calls, here we have to create a message
2357 	 * where the name of the new entry comes first, and the data describing
2358 	 * the entry comes second.
2359 	 * Hence we can't rely on our handy fuse_internal_newentry() routine,
2360 	 * but put together the message manually and just call the core part.
2361 	 */
2362 
2363 	len = strlen(target) + 1;
2364 	fdisp_init(&fdi, len + cnp->cn_namelen + 1);
2365 	fdisp_make_vp(&fdi, FUSE_SYMLINK, dvp, curthread, NULL);
2366 
2367 	memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
2368 	((char *)fdi.indata)[cnp->cn_namelen] = '\0';
2369 	memcpy((char *)fdi.indata + cnp->cn_namelen + 1, target, len);
2370 
2371 	err = fuse_internal_newentry_core(dvp, vpp, cnp, VLNK, &fdi);
2372 	fdisp_destroy(&fdi);
2373 	return err;
2374 }
2375 
2376 /*
2377     struct vnop_write_args {
2378 	struct vnode *a_vp;
2379 	struct uio *a_uio;
2380 	int  a_ioflag;
2381 	struct ucred *a_cred;
2382     };
2383 */
2384 static int
2385 fuse_vnop_write(struct vop_write_args *ap)
2386 {
2387 	struct vnode *vp = ap->a_vp;
2388 	struct uio *uio = ap->a_uio;
2389 	int ioflag = ap->a_ioflag;
2390 	struct ucred *cred = ap->a_cred;
2391 	pid_t pid = curthread->td_proc->p_pid;
2392 	struct fuse_filehandle *fufh;
2393 	int err;
2394 	bool closefufh = false, directio;
2395 
2396 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
2397 
2398 	if (fuse_isdeadfs(vp)) {
2399 		return ENXIO;
2400 	}
2401 
2402 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
2403 		ioflag |= IO_DIRECT;
2404 	}
2405 
2406 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2407 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2408 		/*
2409 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2410 		 * must implicitly open the file here
2411 		 */
2412 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2413 		closefufh = true;
2414 	}
2415 	if (err) {
2416 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
2417 		return err;
2418 	}
2419 
2420 	/*
2421          * Ideally, when the daemon asks for direct io at open time, the
2422          * standard file flag should be set according to this, so that would
2423          * just change the default mode, which later on could be changed via
2424          * fcntl(2).
2425          * But this doesn't work, the O_DIRECT flag gets cleared at some point
2426          * (don't know where). So to make any use of the Fuse direct_io option,
2427          * we hardwire it into the file's private data (similarly to Linux,
2428          * btw.).
2429          */
2430 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
2431 
2432 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2433 	if (directio) {
2434 		off_t start, end, filesize;
2435 		bool pages = (ioflag & IO_VMIO) != 0;
2436 
2437 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct write of vnode");
2438 
2439 		err = fuse_vnode_size(vp, &filesize, cred, curthread);
2440 		if (err)
2441 			goto out;
2442 
2443 		start = uio->uio_offset;
2444 		end = start + uio->uio_resid;
2445 		if (!pages) {
2446 			err = fuse_inval_buf_range(vp, filesize, start,
2447 			    end);
2448 			if (err)
2449 				goto out;
2450 		}
2451 		err = fuse_write_directbackend(vp, uio, cred, fufh,
2452 			filesize, ioflag, pages);
2453 	} else {
2454 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2455 			"buffered write of vnode");
2456 		if (!fsess_opt_writeback(vnode_mount(vp)))
2457 			ioflag |= IO_SYNC;
2458 		err = fuse_write_biobackend(vp, uio, cred, fufh, ioflag, pid);
2459 	}
2460 	fuse_internal_clear_suid_on_write(vp, cred, uio->uio_td);
2461 
2462 out:
2463 	if (closefufh)
2464 		fuse_filehandle_close(vp, fufh, curthread, cred);
2465 
2466 	return (err);
2467 }
2468 
2469 static daddr_t
2470 fuse_gbp_getblkno(struct vnode *vp, vm_ooffset_t off)
2471 {
2472 	const int biosize = fuse_iosize(vp);
2473 
2474 	return (off / biosize);
2475 }
2476 
2477 static int
2478 fuse_gbp_getblksz(struct vnode *vp, daddr_t lbn, long *blksz)
2479 {
2480 	off_t filesize;
2481 	int err;
2482 	const int biosize = fuse_iosize(vp);
2483 
2484 	err = fuse_vnode_size(vp, &filesize, NULL, NULL);
2485 	if (err) {
2486 		/* This will turn into a SIGBUS */
2487 		return (EIO);
2488 	} else if ((off_t)lbn * biosize >= filesize) {
2489 		*blksz = 0;
2490 	} else if ((off_t)(lbn + 1) * biosize > filesize) {
2491 		*blksz = filesize - (off_t)lbn *biosize;
2492 	} else {
2493 		*blksz = biosize;
2494 	}
2495 	return (0);
2496 }
2497 
2498 /*
2499     struct vnop_getpages_args {
2500 	struct vnode *a_vp;
2501 	vm_page_t *a_m;
2502 	int a_count;
2503 	int a_reqpage;
2504     };
2505 */
2506 static int
2507 fuse_vnop_getpages(struct vop_getpages_args *ap)
2508 {
2509 	struct vnode *vp = ap->a_vp;
2510 
2511 	if (!fsess_opt_mmap(vnode_mount(vp))) {
2512 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2513 			"called on non-cacheable vnode??\n");
2514 		return (VM_PAGER_ERROR);
2515 	}
2516 
2517 	return (vfs_bio_getpages(vp, ap->a_m, ap->a_count, ap->a_rbehind,
2518 	    ap->a_rahead, fuse_gbp_getblkno, fuse_gbp_getblksz));
2519 }
2520 
2521 static const char extattr_namespace_separator = '.';
2522 
2523 /*
2524     struct vop_getextattr_args {
2525 	struct vop_generic_args a_gen;
2526 	struct vnode *a_vp;
2527 	int a_attrnamespace;
2528 	const char *a_name;
2529 	struct uio *a_uio;
2530 	size_t *a_size;
2531 	struct ucred *a_cred;
2532 	struct thread *a_td;
2533     };
2534 */
2535 static int
2536 fuse_vnop_getextattr(struct vop_getextattr_args *ap)
2537 {
2538 	struct vnode *vp = ap->a_vp;
2539 	struct uio *uio = ap->a_uio;
2540 	struct fuse_dispatcher fdi;
2541 	struct fuse_getxattr_in *get_xattr_in;
2542 	struct fuse_getxattr_out *get_xattr_out;
2543 	struct mount *mp = vnode_mount(vp);
2544 	struct thread *td = ap->a_td;
2545 	struct ucred *cred = ap->a_cred;
2546 	char *prefix;
2547 	char *attr_str;
2548 	size_t len;
2549 	int err;
2550 
2551 	if (fuse_isdeadfs(vp))
2552 		return (ENXIO);
2553 
2554 	if (fsess_not_impl(mp, FUSE_GETXATTR))
2555 		return EOPNOTSUPP;
2556 
2557 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2558 	if (err)
2559 		return err;
2560 
2561 	/* Default to looking for user attributes. */
2562 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2563 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2564 	else
2565 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2566 
2567 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2568 	    strlen(ap->a_name) + 1;
2569 
2570 	fdisp_init(&fdi, len + sizeof(*get_xattr_in));
2571 	fdisp_make_vp(&fdi, FUSE_GETXATTR, vp, td, cred);
2572 
2573 	get_xattr_in = fdi.indata;
2574 	/*
2575 	 * Check to see whether we're querying the available size or
2576 	 * issuing the actual request.  If we pass in 0, we get back struct
2577 	 * fuse_getxattr_out.  If we pass in a non-zero size, we get back
2578 	 * that much data, without the struct fuse_getxattr_out header.
2579 	 */
2580 	if (uio == NULL)
2581 		get_xattr_in->size = 0;
2582 	else
2583 		get_xattr_in->size = uio->uio_resid;
2584 
2585 	attr_str = (char *)fdi.indata + sizeof(*get_xattr_in);
2586 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2587 	    ap->a_name);
2588 
2589 	err = fdisp_wait_answ(&fdi);
2590 	if (err != 0) {
2591 		if (err == ENOSYS) {
2592 			fsess_set_notimpl(mp, FUSE_GETXATTR);
2593 			err = EOPNOTSUPP;
2594 		}
2595 		goto out;
2596 	}
2597 
2598 	get_xattr_out = fdi.answ;
2599 
2600 	if (ap->a_size != NULL)
2601 		*ap->a_size = get_xattr_out->size;
2602 
2603 	if (uio != NULL)
2604 		err = uiomove(fdi.answ, fdi.iosize, uio);
2605 
2606 out:
2607 	fdisp_destroy(&fdi);
2608 	return (err);
2609 }
2610 
2611 /*
2612     struct vop_setextattr_args {
2613 	struct vop_generic_args a_gen;
2614 	struct vnode *a_vp;
2615 	int a_attrnamespace;
2616 	const char *a_name;
2617 	struct uio *a_uio;
2618 	struct ucred *a_cred;
2619 	struct thread *a_td;
2620     };
2621 */
2622 static int
2623 fuse_vnop_setextattr(struct vop_setextattr_args *ap)
2624 {
2625 	struct vnode *vp = ap->a_vp;
2626 	struct uio *uio = ap->a_uio;
2627 	struct fuse_dispatcher fdi;
2628 	struct fuse_setxattr_in *set_xattr_in;
2629 	struct mount *mp = vnode_mount(vp);
2630 	struct thread *td = ap->a_td;
2631 	struct ucred *cred = ap->a_cred;
2632 	char *prefix;
2633 	size_t len;
2634 	char *attr_str;
2635 	int err;
2636 
2637 	if (fuse_isdeadfs(vp))
2638 		return (ENXIO);
2639 
2640 	if (fsess_not_impl(mp, FUSE_SETXATTR))
2641 		return EOPNOTSUPP;
2642 
2643 	if (vfs_isrdonly(mp))
2644 		return EROFS;
2645 
2646 	/* Deleting xattrs must use VOP_DELETEEXTATTR instead */
2647 	if (ap->a_uio == NULL) {
2648 		/*
2649 		 * If we got here as fallback from VOP_DELETEEXTATTR, then
2650 		 * return EOPNOTSUPP.
2651 		 */
2652 		if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
2653 			return (EOPNOTSUPP);
2654 		else
2655 			return (EINVAL);
2656 	}
2657 
2658 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
2659 		VWRITE);
2660 	if (err)
2661 		return err;
2662 
2663 	/* Default to looking for user attributes. */
2664 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2665 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2666 	else
2667 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2668 
2669 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2670 	    strlen(ap->a_name) + 1;
2671 
2672 	fdisp_init(&fdi, len + sizeof(*set_xattr_in) + uio->uio_resid);
2673 	fdisp_make_vp(&fdi, FUSE_SETXATTR, vp, td, cred);
2674 
2675 	set_xattr_in = fdi.indata;
2676 	set_xattr_in->size = uio->uio_resid;
2677 
2678 	attr_str = (char *)fdi.indata + sizeof(*set_xattr_in);
2679 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2680 	    ap->a_name);
2681 
2682 	err = uiomove((char *)fdi.indata + sizeof(*set_xattr_in) + len,
2683 	    uio->uio_resid, uio);
2684 	if (err != 0) {
2685 		goto out;
2686 	}
2687 
2688 	err = fdisp_wait_answ(&fdi);
2689 
2690 	if (err == ENOSYS) {
2691 		fsess_set_notimpl(mp, FUSE_SETXATTR);
2692 		err = EOPNOTSUPP;
2693 	}
2694 	if (err == ERESTART) {
2695 		/* Can't restart after calling uiomove */
2696 		err = EINTR;
2697 	}
2698 
2699 out:
2700 	fdisp_destroy(&fdi);
2701 	return (err);
2702 }
2703 
2704 /*
2705  * The Linux / FUSE extended attribute list is simply a collection of
2706  * NUL-terminated strings.  The FreeBSD extended attribute list is a single
2707  * byte length followed by a non-NUL terminated string.  So, this allows
2708  * conversion of the Linux / FUSE format to the FreeBSD format in place.
2709  * Linux attribute names are reported with the namespace as a prefix (e.g.
2710  * "user.attribute_name"), but in FreeBSD they are reported without the
2711  * namespace prefix (e.g. "attribute_name").  So, we're going from:
2712  *
2713  * user.attr_name1\0user.attr_name2\0
2714  *
2715  * to:
2716  *
2717  * <num>attr_name1<num>attr_name2
2718  *
2719  * Where "<num>" is a single byte number of characters in the attribute name.
2720  *
2721  * Args:
2722  * prefix - exattr namespace prefix string
2723  * list, list_len - input list with namespace prefixes
2724  * bsd_list, bsd_list_len - output list compatible with bsd vfs
2725  */
2726 static int
2727 fuse_xattrlist_convert(char *prefix, const char *list, int list_len,
2728     char *bsd_list, int *bsd_list_len)
2729 {
2730 	int len, pos, dist_to_next, prefix_len;
2731 
2732 	pos = 0;
2733 	*bsd_list_len = 0;
2734 	prefix_len = strlen(prefix);
2735 
2736 	while (pos < list_len && list[pos] != '\0') {
2737 		dist_to_next = strlen(&list[pos]) + 1;
2738 		if (bcmp(&list[pos], prefix, prefix_len) == 0 &&
2739 		    list[pos + prefix_len] == extattr_namespace_separator) {
2740 			len = dist_to_next -
2741 			    (prefix_len + sizeof(extattr_namespace_separator)) - 1;
2742 			if (len >= EXTATTR_MAXNAMELEN)
2743 				return (ENAMETOOLONG);
2744 
2745 			bsd_list[*bsd_list_len] = len;
2746 			memcpy(&bsd_list[*bsd_list_len + 1],
2747 			    &list[pos + prefix_len +
2748 			    sizeof(extattr_namespace_separator)], len);
2749 
2750 			*bsd_list_len += len + 1;
2751 		}
2752 
2753 		pos += dist_to_next;
2754 	}
2755 
2756 	return (0);
2757 }
2758 
2759 /*
2760  * List extended attributes
2761  *
2762  * The FUSE_LISTXATTR operation is based on Linux's listxattr(2) syscall, which
2763  * has a number of differences compared to its FreeBSD equivalent,
2764  * extattr_list_file:
2765  *
2766  * - FUSE_LISTXATTR returns all extended attributes across all namespaces,
2767  *   whereas listxattr(2) only returns attributes for a single namespace
2768  * - FUSE_LISTXATTR prepends each attribute name with "namespace."
2769  * - If the provided buffer is not large enough to hold the result,
2770  *   FUSE_LISTXATTR should return ERANGE, whereas listxattr is expected to
2771  *   return as many results as will fit.
2772  */
2773 /*
2774     struct vop_listextattr_args {
2775 	struct vop_generic_args a_gen;
2776 	struct vnode *a_vp;
2777 	int a_attrnamespace;
2778 	struct uio *a_uio;
2779 	size_t *a_size;
2780 	struct ucred *a_cred;
2781 	struct thread *a_td;
2782     };
2783 */
2784 static int
2785 fuse_vnop_listextattr(struct vop_listextattr_args *ap)
2786 {
2787 	struct vnode *vp = ap->a_vp;
2788 	struct uio *uio = ap->a_uio;
2789 	struct fuse_dispatcher fdi;
2790 	struct fuse_listxattr_in *list_xattr_in;
2791 	struct fuse_listxattr_out *list_xattr_out;
2792 	struct mount *mp = vnode_mount(vp);
2793 	struct thread *td = ap->a_td;
2794 	struct ucred *cred = ap->a_cred;
2795 	char *prefix;
2796 	char *bsd_list = NULL;
2797 	char *linux_list;
2798 	int bsd_list_len;
2799 	int linux_list_len;
2800 	int err;
2801 
2802 	if (fuse_isdeadfs(vp))
2803 		return (ENXIO);
2804 
2805 	if (fsess_not_impl(mp, FUSE_LISTXATTR))
2806 		return EOPNOTSUPP;
2807 
2808 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2809 	if (err)
2810 		return err;
2811 
2812 	/*
2813 	 * Add space for a NUL and the period separator if enabled.
2814 	 * Default to looking for user attributes.
2815 	 */
2816 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2817 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2818 	else
2819 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2820 
2821 	fdisp_init(&fdi, sizeof(*list_xattr_in));
2822 	fdisp_make_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2823 
2824 	/*
2825 	 * Retrieve Linux / FUSE compatible list size.
2826 	 */
2827 	list_xattr_in = fdi.indata;
2828 	list_xattr_in->size = 0;
2829 
2830 	err = fdisp_wait_answ(&fdi);
2831 	if (err != 0) {
2832 		if (err == ENOSYS) {
2833 			fsess_set_notimpl(mp, FUSE_LISTXATTR);
2834 			err = EOPNOTSUPP;
2835 		}
2836 		goto out;
2837 	}
2838 
2839 	list_xattr_out = fdi.answ;
2840 	linux_list_len = list_xattr_out->size;
2841 	if (linux_list_len == 0) {
2842 		if (ap->a_size != NULL)
2843 			*ap->a_size = linux_list_len;
2844 		goto out;
2845 	}
2846 
2847 	/*
2848 	 * Retrieve Linux / FUSE compatible list values.
2849 	 */
2850 	fdisp_refresh_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2851 	list_xattr_in = fdi.indata;
2852 	list_xattr_in->size = linux_list_len;
2853 
2854 	err = fdisp_wait_answ(&fdi);
2855 	if (err == ERANGE) {
2856 		/*
2857 		 * Race detected.  The attribute list must've grown since the
2858 		 * first FUSE_LISTXATTR call.  Start over.  Go all the way back
2859 		 * to userland so we can process signals, if necessary, before
2860 		 * restarting.
2861 		 */
2862 		err = ERESTART;
2863 		goto out;
2864 	} else if (err != 0)
2865 		goto out;
2866 
2867 	linux_list = fdi.answ;
2868 	/* FUSE doesn't allow the server to return more data than requested */
2869 	if (fdi.iosize > linux_list_len) {
2870 		struct fuse_data *data = fuse_get_mpdata(mp);
2871 
2872 		fuse_warn(data, FSESS_WARN_LSEXTATTR_LONG,
2873 			"server returned "
2874 			"more extended attribute data than requested; "
2875 			"should've returned ERANGE instead.");
2876 	} else {
2877 		/* But returning less data is fine */
2878 		linux_list_len = fdi.iosize;
2879 	}
2880 
2881 	/*
2882 	 * Retrieve the BSD compatible list values.
2883 	 * The Linux / FUSE attribute list format isn't the same
2884 	 * as FreeBSD's format. So we need to transform it into
2885 	 * FreeBSD's format before giving it to the user.
2886 	 */
2887 	bsd_list = malloc(linux_list_len, M_TEMP, M_WAITOK);
2888 	err = fuse_xattrlist_convert(prefix, linux_list, linux_list_len,
2889 	    bsd_list, &bsd_list_len);
2890 	if (err != 0)
2891 		goto out;
2892 
2893 	if (ap->a_size != NULL)
2894 		*ap->a_size = bsd_list_len;
2895 
2896 	if (uio != NULL)
2897 		err = uiomove(bsd_list, bsd_list_len, uio);
2898 
2899 out:
2900 	free(bsd_list, M_TEMP);
2901 	fdisp_destroy(&fdi);
2902 	return (err);
2903 }
2904 
2905 /*
2906     struct vop_deallocate_args {
2907 	struct vop_generic_args a_gen;
2908 	struct vnode *a_vp;
2909 	off_t *a_offset;
2910 	off_t *a_len;
2911 	int a_flags;
2912 	int a_ioflag;
2913         struct ucred *a_cred;
2914     };
2915 */
2916 static int
2917 fuse_vnop_deallocate(struct vop_deallocate_args *ap)
2918 {
2919 	struct vnode *vp = ap->a_vp;
2920 	struct mount *mp = vnode_mount(vp);
2921 	struct fuse_filehandle *fufh;
2922 	struct fuse_dispatcher fdi;
2923 	struct fuse_fallocate_in *ffi;
2924 	struct ucred *cred = ap->a_cred;
2925 	pid_t pid = curthread->td_proc->p_pid;
2926 	off_t *len = ap->a_len;
2927 	off_t *offset = ap->a_offset;
2928 	int ioflag = ap->a_ioflag;
2929 	off_t filesize;
2930 	int err;
2931 	bool closefufh = false;
2932 
2933 	if (fuse_isdeadfs(vp))
2934 		return (ENXIO);
2935 
2936 	if (vfs_isrdonly(mp))
2937 		return (EROFS);
2938 
2939 	if (fsess_not_impl(mp, FUSE_FALLOCATE))
2940 		goto fallback;
2941 
2942 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2943 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2944 		/*
2945 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2946 		 * must implicitly open the file here
2947 		 */
2948 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2949 		closefufh = true;
2950 	}
2951 	if (err)
2952 		return (err);
2953 
2954 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2955 
2956 	err = fuse_vnode_size(vp, &filesize, cred, curthread);
2957 	if (err)
2958 		goto out;
2959 	fuse_inval_buf_range(vp, filesize, *offset, *offset + *len);
2960 
2961 	fdisp_init(&fdi, sizeof(*ffi));
2962 	fdisp_make_vp(&fdi, FUSE_FALLOCATE, vp, curthread, cred);
2963 	ffi = fdi.indata;
2964 	ffi->fh = fufh->fh_id;
2965 	ffi->offset = *offset;
2966 	ffi->length = *len;
2967 	/*
2968 	 * FreeBSD's fspacectl is equivalent to Linux's fallocate with
2969 	 * mode == FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE
2970 	 */
2971 	ffi->mode = FUSE_FALLOC_FL_PUNCH_HOLE | FUSE_FALLOC_FL_KEEP_SIZE;
2972 	err = fdisp_wait_answ(&fdi);
2973 
2974 	if (err == ENOSYS) {
2975 		fsess_set_notimpl(mp, FUSE_FALLOCATE);
2976 		goto fallback;
2977 	} else if (err == EOPNOTSUPP) {
2978 		/*
2979 		 * The file system server does not support FUSE_FALLOCATE with
2980 		 * the supplied mode for this particular file.
2981 		 */
2982 		goto fallback;
2983 	} else if (!err) {
2984 		/*
2985 		 * Clip the returned offset to EoF.  Do it here rather than
2986 		 * before FUSE_FALLOCATE just in case the kernel's cached file
2987 		 * size is out of date.  Unfortunately, FUSE does not return
2988 		 * any information about filesize from that operation.
2989 		 */
2990 		*offset = MIN(*offset + *len, filesize);
2991 		*len = 0;
2992 		fuse_vnode_undirty_cached_timestamps(vp, false);
2993 		fuse_internal_clear_suid_on_write(vp, cred, curthread);
2994 
2995 		if (ioflag & IO_SYNC)
2996 			err = fuse_internal_fsync(vp, curthread, MNT_WAIT,
2997 			    false);
2998 	}
2999 
3000 out:
3001 	if (closefufh)
3002 		fuse_filehandle_close(vp, fufh, curthread, cred);
3003 
3004 	return (err);
3005 
3006 fallback:
3007 	if (closefufh)
3008 		fuse_filehandle_close(vp, fufh, curthread, cred);
3009 
3010 	return (vop_stddeallocate(ap));
3011 }
3012 
3013 /*
3014     struct vop_deleteextattr_args {
3015 	struct vop_generic_args a_gen;
3016 	struct vnode *a_vp;
3017 	int a_attrnamespace;
3018 	const char *a_name;
3019 	struct ucred *a_cred;
3020 	struct thread *a_td;
3021     };
3022 */
3023 static int
3024 fuse_vnop_deleteextattr(struct vop_deleteextattr_args *ap)
3025 {
3026 	struct vnode *vp = ap->a_vp;
3027 	struct fuse_dispatcher fdi;
3028 	struct mount *mp = vnode_mount(vp);
3029 	struct thread *td = ap->a_td;
3030 	struct ucred *cred = ap->a_cred;
3031 	char *prefix;
3032 	size_t len;
3033 	char *attr_str;
3034 	int err;
3035 
3036 	if (fuse_isdeadfs(vp))
3037 		return (ENXIO);
3038 
3039 	if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
3040 		return EOPNOTSUPP;
3041 
3042 	if (vfs_isrdonly(mp))
3043 		return EROFS;
3044 
3045 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
3046 		VWRITE);
3047 	if (err)
3048 		return err;
3049 
3050 	/* Default to looking for user attributes. */
3051 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
3052 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
3053 	else
3054 		prefix = EXTATTR_NAMESPACE_USER_STRING;
3055 
3056 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
3057 	    strlen(ap->a_name) + 1;
3058 
3059 	fdisp_init(&fdi, len);
3060 	fdisp_make_vp(&fdi, FUSE_REMOVEXATTR, vp, td, cred);
3061 
3062 	attr_str = fdi.indata;
3063 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
3064 	    ap->a_name);
3065 
3066 	err = fdisp_wait_answ(&fdi);
3067 	if (err == ENOSYS) {
3068 		fsess_set_notimpl(mp, FUSE_REMOVEXATTR);
3069 		err = EOPNOTSUPP;
3070 	}
3071 
3072 	fdisp_destroy(&fdi);
3073 	return (err);
3074 }
3075 
3076 /*
3077     struct vnop_print_args {
3078 	struct vnode *a_vp;
3079     };
3080 */
3081 static int
3082 fuse_vnop_print(struct vop_print_args *ap)
3083 {
3084 	struct fuse_vnode_data *fvdat = VTOFUD(ap->a_vp);
3085 
3086 	printf("nodeid: %ju, parent nodeid: %ju, nlookup: %ju, flag: %#x\n",
3087 	    (uintmax_t)VTOILLU(ap->a_vp), (uintmax_t)fvdat->parent_nid,
3088 	    (uintmax_t)fvdat->nlookup,
3089 	    fvdat->flag);
3090 
3091 	return 0;
3092 }
3093 
3094 /*
3095  * Get an NFS filehandle for a FUSE file.
3096  *
3097  * This will only work for FUSE file systems that guarantee the uniqueness of
3098  * nodeid:generation, which most don't.
3099  */
3100 /*
3101 vop_vptofh {
3102 	IN struct vnode *a_vp;
3103 	IN struct fid *a_fhp;
3104 };
3105 */
3106 static int
3107 fuse_vnop_vptofh(struct vop_vptofh_args *ap)
3108 {
3109 	struct vnode *vp = ap->a_vp;
3110 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
3111 	struct fuse_fid *fhp = (struct fuse_fid *)(ap->a_fhp);
3112 	_Static_assert(sizeof(struct fuse_fid) <= sizeof(struct fid),
3113 		"FUSE fid type is too big");
3114 	struct mount *mp = vnode_mount(vp);
3115 	struct fuse_data *data = fuse_get_mpdata(mp);
3116 	struct vattr va;
3117 	int err;
3118 
3119 	if (!(data->dataflags & FSESS_EXPORT_SUPPORT)) {
3120 		/* NFS requires lookups for "." and ".." */
3121 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3122 			"VOP_VPTOFH without FUSE_EXPORT_SUPPORT");
3123 		return EOPNOTSUPP;
3124 	}
3125 	if ((mp->mnt_flag & MNT_EXPORTED) &&
3126 		!(data->dataflags & FSESS_NO_OPENDIR_SUPPORT))
3127 	{
3128 		/*
3129 		 * NFS is stateless, so nfsd must reopen a directory on every
3130 		 * call to VOP_READDIR, passing in the d_off field from the
3131 		 * final dirent of the previous invocation.  But without
3132 		 * FUSE_NO_OPENDIR_SUPPORT, the FUSE protocol does not
3133 		 * guarantee that d_off will be valid after a directory is
3134 		 * closed and reopened.  So prohibit exporting FUSE file
3135 		 * systems that don't set that flag.
3136 		 *
3137 		 * But userspace NFS servers don't have this problem.
3138                  */
3139 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3140 			"VOP_VPTOFH without FUSE_NO_OPENDIR_SUPPORT");
3141 		return EOPNOTSUPP;
3142 	}
3143 
3144 	err = fuse_internal_getattr(vp, &va, curthread->td_ucred, curthread);
3145 	if (err)
3146 		return err;
3147 
3148 	/*ip = VTOI(ap->a_vp);*/
3149 	/*ufhp = (struct ufid *)ap->a_fhp;*/
3150 	fhp->len = sizeof(struct fuse_fid);
3151 	fhp->nid = fvdat->nid;
3152 	if (fvdat->generation <= UINT32_MAX)
3153 		fhp->gen = fvdat->generation;
3154 	else
3155 		return EOVERFLOW;
3156 	return (0);
3157 }
3158