xref: /freebsd/sys/fs/fuse/fuse_vnops.c (revision d30a1689f5b37e78ea189232a8b94a7011dc0dc8)
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 	ssize_t r = 0;
815 	pid_t pid;
816 	int err;
817 
818 	if (mp != vnode_mount(outvp))
819 		goto fallback;
820 
821 	if (incred->cr_uid != outcred->cr_uid)
822 		goto fallback;
823 
824 	if (incred->cr_groups[0] != outcred->cr_groups[0])
825 		goto fallback;
826 
827 	if (fsess_not_impl(mp, FUSE_COPY_FILE_RANGE))
828 		goto fallback;
829 
830 	if (ap->a_fsizetd == NULL)
831 		td = curthread;
832 	else
833 		td = ap->a_fsizetd;
834 	pid = td->td_proc->p_pid;
835 
836 	/* Lock both vnodes, avoiding risk of deadlock. */
837 	do {
838 		err = vn_lock(outvp, LK_EXCLUSIVE);
839 		if (invp == outvp)
840 			break;
841 		if (err == 0) {
842 			err = vn_lock(invp, LK_SHARED | LK_NOWAIT);
843 			if (err == 0)
844 				break;
845 			VOP_UNLOCK(outvp);
846 			err = vn_lock(invp, LK_SHARED);
847 			if (err == 0)
848 				VOP_UNLOCK(invp);
849 		}
850 	} while (err == 0);
851 	if (err != 0)
852 		return (err);
853 
854 	err = fuse_filehandle_getrw(invp, FREAD, &infufh, incred, pid);
855 	if (err)
856 		goto unlock;
857 
858 	err = fuse_filehandle_getrw(outvp, FWRITE, &outfufh, outcred, pid);
859 	if (err)
860 		goto unlock;
861 
862 	io.uio_resid = *ap->a_lenp;
863 	if (ap->a_fsizetd) {
864 		io.uio_offset = *ap->a_outoffp;
865 		err = vn_rlimit_fsizex(outvp, &io, 0, &r, ap->a_fsizetd);
866 		if (err != 0)
867 			goto unlock;
868 	}
869 
870 	err = fuse_vnode_size(outvp, &outfilesize, outcred, curthread);
871 	if (err)
872 		goto unlock;
873 
874 	err = fuse_inval_buf_range(outvp, outfilesize, *ap->a_outoffp,
875 		*ap->a_outoffp + io.uio_resid);
876 	if (err)
877 		goto unlock;
878 
879 	fdisp_init(&fdi, sizeof(*fcfri));
880 	fdisp_make_vp(&fdi, FUSE_COPY_FILE_RANGE, invp, td, incred);
881 	fcfri = fdi.indata;
882 	fcfri->fh_in = infufh->fh_id;
883 	fcfri->off_in = *ap->a_inoffp;
884 	fcfri->nodeid_out = VTOI(outvp);
885 	fcfri->fh_out = outfufh->fh_id;
886 	fcfri->off_out = *ap->a_outoffp;
887 	fcfri->len = io.uio_resid;
888 	fcfri->flags = 0;
889 
890 	err = fdisp_wait_answ(&fdi);
891 	if (err == 0) {
892 		fwo = fdi.answ;
893 		*ap->a_lenp = fwo->size;
894 		*ap->a_inoffp += fwo->size;
895 		*ap->a_outoffp += fwo->size;
896 		fuse_internal_clear_suid_on_write(outvp, outcred, td);
897 		if (*ap->a_outoffp > outfvdat->cached_attrs.va_size) {
898                         fuse_vnode_setsize(outvp, *ap->a_outoffp, false);
899 			getnanouptime(&outfvdat->last_local_modify);
900 		}
901 		fuse_vnode_update(invp, FN_ATIMECHANGE);
902 		fuse_vnode_update(outvp, FN_MTIMECHANGE | FN_CTIMECHANGE);
903 	}
904 	fdisp_destroy(&fdi);
905 
906 unlock:
907 	if (invp != outvp)
908 		VOP_UNLOCK(invp);
909 	VOP_UNLOCK(outvp);
910 
911 	if (err == ENOSYS) {
912 		fsess_set_notimpl(mp, FUSE_COPY_FILE_RANGE);
913 fallback:
914 		err = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp,
915 		    ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags,
916 		    ap->a_incred, ap->a_outcred, ap->a_fsizetd);
917 	}
918 
919 	/*
920 	 * No need to call vn_rlimit_fsizex_res before return, since the uio is
921 	 * local.
922 	 */
923 	return (err);
924 }
925 
926 static void
927 fdisp_make_mknod_for_fallback(
928 	struct fuse_dispatcher *fdip,
929 	struct componentname *cnp,
930 	struct vnode *dvp,
931 	uint64_t parentnid,
932 	struct thread *td,
933 	struct ucred *cred,
934 	mode_t mode,
935 	enum fuse_opcode *op)
936 {
937 	struct fuse_mknod_in *fmni;
938 
939 	fdisp_init(fdip, sizeof(*fmni) + cnp->cn_namelen + 1);
940 	*op = FUSE_MKNOD;
941 	fdisp_make(fdip, *op, vnode_mount(dvp), parentnid, td, cred);
942 	fmni = fdip->indata;
943 	fmni->mode = mode;
944 	fmni->rdev = 0;
945 	memcpy((char *)fdip->indata + sizeof(*fmni), cnp->cn_nameptr,
946 	    cnp->cn_namelen);
947 	((char *)fdip->indata)[sizeof(*fmni) + cnp->cn_namelen] = '\0';
948 }
949 /*
950     struct vnop_create_args {
951 	struct vnode *a_dvp;
952 	struct vnode **a_vpp;
953 	struct componentname *a_cnp;
954 	struct vattr *a_vap;
955     };
956 */
957 static int
958 fuse_vnop_create(struct vop_create_args *ap)
959 {
960 	struct vnode *dvp = ap->a_dvp;
961 	struct vnode **vpp = ap->a_vpp;
962 	struct componentname *cnp = ap->a_cnp;
963 	struct vattr *vap = ap->a_vap;
964 	struct thread *td = curthread;
965 	struct ucred *cred = cnp->cn_cred;
966 
967 	struct fuse_data *data;
968 	struct fuse_create_in *fci;
969 	struct fuse_entry_out *feo;
970 	struct fuse_open_out *foo;
971 	struct fuse_dispatcher fdi, fdi2;
972 	struct fuse_dispatcher *fdip = &fdi;
973 	struct fuse_dispatcher *fdip2 = NULL;
974 
975 	int err;
976 
977 	struct mount *mp = vnode_mount(dvp);
978 	data = fuse_get_mpdata(mp);
979 	uint64_t parentnid = VTOFUD(dvp)->nid;
980 	mode_t mode = MAKEIMODE(vap->va_type, vap->va_mode);
981 	enum fuse_opcode op;
982 	int flags;
983 
984 	if (fuse_isdeadfs(dvp))
985 		return ENXIO;
986 
987 	/* FUSE expects sockets to be created with FUSE_MKNOD */
988 	if (vap->va_type == VSOCK)
989 		return fuse_internal_mknod(dvp, vpp, cnp, vap);
990 
991 	/*
992 	 * VOP_CREATE doesn't tell us the open(2) flags, so we guess.  Only a
993 	 * writable mode makes sense, and we might as well include readability
994 	 * too.
995 	 */
996 	flags = O_RDWR;
997 
998 	bzero(&fdi, sizeof(fdi));
999 
1000 	if (vap->va_type != VREG)
1001 		return (EINVAL);
1002 
1003 	if (fsess_not_impl(mp, FUSE_CREATE) || vap->va_type == VSOCK) {
1004 		/* Fallback to FUSE_MKNOD/FUSE_OPEN */
1005 		fdisp_make_mknod_for_fallback(fdip, cnp, dvp, parentnid, td,
1006 			cred, mode, &op);
1007 	} else {
1008 		/* Use FUSE_CREATE */
1009 		size_t insize;
1010 
1011 		op = FUSE_CREATE;
1012 		fdisp_init(fdip, sizeof(*fci) + cnp->cn_namelen + 1);
1013 		fdisp_make(fdip, op, vnode_mount(dvp), parentnid, td, cred);
1014 		fci = fdip->indata;
1015 		fci->mode = mode;
1016 		fci->flags = O_CREAT | flags;
1017 		if (fuse_libabi_geq(data, 7, 12)) {
1018 			insize = sizeof(*fci);
1019 			fci->umask = td->td_proc->p_pd->pd_cmask;
1020 		} else {
1021 			insize = sizeof(struct fuse_open_in);
1022 		}
1023 
1024 		memcpy((char *)fdip->indata + insize, cnp->cn_nameptr,
1025 		    cnp->cn_namelen);
1026 		((char *)fdip->indata)[insize + cnp->cn_namelen] = '\0';
1027 	}
1028 
1029 	err = fdisp_wait_answ(fdip);
1030 
1031 	if (err) {
1032 		if (err == ENOSYS && op == FUSE_CREATE) {
1033 			fsess_set_notimpl(mp, FUSE_CREATE);
1034 			fdisp_destroy(fdip);
1035 			fdisp_make_mknod_for_fallback(fdip, cnp, dvp,
1036 				parentnid, td, cred, mode, &op);
1037 			err = fdisp_wait_answ(fdip);
1038 		}
1039 		if (err)
1040 			goto out;
1041 	}
1042 
1043 	feo = fdip->answ;
1044 
1045 	if ((err = fuse_internal_checkentry(feo, vap->va_type))) {
1046 		goto out;
1047 	}
1048 
1049 	if (op == FUSE_CREATE) {
1050 		if (fuse_libabi_geq(data, 7, 9))
1051 			foo = (struct fuse_open_out*)(feo + 1);
1052 		else
1053 			foo = (struct fuse_open_out*)((char*)feo +
1054 				FUSE_COMPAT_ENTRY_OUT_SIZE);
1055 	} else {
1056 		/* Issue a separate FUSE_OPEN */
1057 		struct fuse_open_in *foi;
1058 
1059 		fdip2 = &fdi2;
1060 		fdisp_init(fdip2, sizeof(*foi));
1061 		fdisp_make(fdip2, FUSE_OPEN, vnode_mount(dvp), feo->nodeid, td,
1062 			cred);
1063 		foi = fdip2->indata;
1064 		foi->flags = flags;
1065 		err = fdisp_wait_answ(fdip2);
1066 		if (err)
1067 			goto out;
1068 		foo = fdip2->answ;
1069 	}
1070 	err = fuse_vnode_get(mp, feo, feo->nodeid, dvp, vpp, cnp, vap->va_type);
1071 	if (err) {
1072 		struct fuse_release_in *fri;
1073 		uint64_t nodeid = feo->nodeid;
1074 		uint64_t fh_id = foo->fh;
1075 
1076 		fdisp_init(fdip, sizeof(*fri));
1077 		fdisp_make(fdip, FUSE_RELEASE, mp, nodeid, td, cred);
1078 		fri = fdip->indata;
1079 		fri->fh = fh_id;
1080 		fri->flags = flags;
1081 		fuse_insert_callback(fdip->tick, fuse_internal_forget_callback);
1082 		fuse_insert_message(fdip->tick, false);
1083 		goto out;
1084 	}
1085 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnop_create");
1086 	fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid,
1087 		feo->attr_valid_nsec, NULL, true);
1088 
1089 	fuse_filehandle_init(*vpp, FUFH_RDWR, NULL, td, cred, foo);
1090 	fuse_vnode_open(*vpp, foo->open_flags, td);
1091 	/*
1092 	 * Purge the parent's attribute cache because the daemon should've
1093 	 * updated its mtime and ctime
1094 	 */
1095 	fuse_vnode_clear_attr_cache(dvp);
1096 	cache_purge_negative(dvp);
1097 
1098 out:
1099 	if (fdip2)
1100 		fdisp_destroy(fdip2);
1101 	fdisp_destroy(fdip);
1102 	return err;
1103 }
1104 
1105 /*
1106     struct vnop_fdatasync_args {
1107 	struct vop_generic_args a_gen;
1108 	struct vnode * a_vp;
1109 	struct thread * a_td;
1110     };
1111 */
1112 static int
1113 fuse_vnop_fdatasync(struct vop_fdatasync_args *ap)
1114 {
1115 	struct vnode *vp = ap->a_vp;
1116 	struct thread *td = ap->a_td;
1117 	int waitfor = MNT_WAIT;
1118 
1119 	int err = 0;
1120 
1121 	if (fuse_isdeadfs(vp)) {
1122 		return 0;
1123 	}
1124 	if ((err = vop_stdfdatasync_buf(ap)))
1125 		return err;
1126 
1127 	return fuse_internal_fsync(vp, td, waitfor, true);
1128 }
1129 
1130 /*
1131     struct vnop_fsync_args {
1132 	struct vop_generic_args a_gen;
1133 	struct vnode * a_vp;
1134 	int  a_waitfor;
1135 	struct thread * a_td;
1136     };
1137 */
1138 static int
1139 fuse_vnop_fsync(struct vop_fsync_args *ap)
1140 {
1141 	struct vnode *vp = ap->a_vp;
1142 	struct thread *td = ap->a_td;
1143 	int waitfor = ap->a_waitfor;
1144 	int err = 0;
1145 
1146 	if (fuse_isdeadfs(vp)) {
1147 		return 0;
1148 	}
1149 	if ((err = vop_stdfsync(ap)))
1150 		return err;
1151 
1152 	return fuse_internal_fsync(vp, td, waitfor, false);
1153 }
1154 
1155 /*
1156     struct vnop_getattr_args {
1157 	struct vnode *a_vp;
1158 	struct vattr *a_vap;
1159 	struct ucred *a_cred;
1160 	struct thread *a_td;
1161     };
1162 */
1163 static int
1164 fuse_vnop_getattr(struct vop_getattr_args *ap)
1165 {
1166 	struct vnode *vp = ap->a_vp;
1167 	struct vattr *vap = ap->a_vap;
1168 	struct ucred *cred = ap->a_cred;
1169 	struct thread *td = curthread;
1170 
1171 	int err = 0;
1172 	int dataflags;
1173 
1174 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
1175 
1176 	/* Note that we are not bailing out on a dead file system just yet. */
1177 
1178 	if (!(dataflags & FSESS_INITED)) {
1179 		if (!vnode_isvroot(vp)) {
1180 			fdata_set_dead(fuse_get_mpdata(vnode_mount(vp)));
1181 			err = ENOTCONN;
1182 			return err;
1183 		} else {
1184 			goto fake;
1185 		}
1186 	}
1187 	err = fuse_internal_getattr(vp, vap, cred, td);
1188 	if (err == ENOTCONN && vnode_isvroot(vp)) {
1189 		/* see comment in fuse_vfsop_statfs() */
1190 		goto fake;
1191 	} else {
1192 		return err;
1193 	}
1194 
1195 fake:
1196 	bzero(vap, sizeof(*vap));
1197 	vap->va_type = vnode_vtype(vp);
1198 
1199 	return 0;
1200 }
1201 
1202 /*
1203     struct vnop_inactive_args {
1204 	struct vnode *a_vp;
1205     };
1206 */
1207 static int
1208 fuse_vnop_inactive(struct vop_inactive_args *ap)
1209 {
1210 	struct vnode *vp = ap->a_vp;
1211 	struct thread *td = curthread;
1212 
1213 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1214 	struct fuse_filehandle *fufh, *fufh_tmp;
1215 
1216 	int need_flush = 1;
1217 
1218 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1219 		if (need_flush && vp->v_type == VREG) {
1220 			if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) {
1221 				fuse_vnode_savesize(vp, NULL, 0);
1222 			}
1223 			if ((fvdat->flag & FN_REVOKED) != 0)
1224 				fuse_io_invalbuf(vp, td);
1225 			else
1226 				fuse_io_flushbuf(vp, MNT_WAIT, td);
1227 			need_flush = 0;
1228 		}
1229 		fuse_filehandle_close(vp, fufh, td, NULL);
1230 	}
1231 
1232 	if ((fvdat->flag & FN_REVOKED) != 0)
1233 		vrecycle(vp);
1234 
1235 	return 0;
1236 }
1237 
1238 /*
1239     struct vnop_ioctl_args {
1240 	struct vnode *a_vp;
1241 	u_long a_command;
1242 	caddr_t a_data;
1243 	int a_fflag;
1244 	struct ucred *a_cred;
1245 	struct thread *a_td;
1246     };
1247 */
1248 static int
1249 fuse_vnop_ioctl(struct vop_ioctl_args *ap)
1250 {
1251 	struct vnode *vp = ap->a_vp;
1252 	struct mount *mp = vnode_mount(vp);
1253 	struct ucred *cred = ap->a_cred;
1254 	off_t *offp;
1255 	pid_t pid = ap->a_td->td_proc->p_pid;
1256 	int err;
1257 
1258 	switch (ap->a_command) {
1259 	case FIOSEEKDATA:
1260 	case FIOSEEKHOLE:
1261 		/* Call FUSE_LSEEK, if we can, or fall back to vop_stdioctl */
1262 		if (fsess_maybe_impl(mp, FUSE_LSEEK)) {
1263 			int whence;
1264 
1265 			offp = ap->a_data;
1266 			if (ap->a_command == FIOSEEKDATA)
1267 				whence = SEEK_DATA;
1268 			else
1269 				whence = SEEK_HOLE;
1270 
1271 			vn_lock(vp, LK_SHARED | LK_RETRY);
1272 			err = fuse_vnop_do_lseek(vp, ap->a_td, cred, pid, offp,
1273 			    whence);
1274 			VOP_UNLOCK(vp);
1275 		}
1276 		if (fsess_not_impl(mp, FUSE_LSEEK))
1277 			err = vop_stdioctl(ap);
1278 		break;
1279 	default:
1280 		/* TODO: implement FUSE_IOCTL */
1281 		err = ENOTTY;
1282 		break;
1283 	}
1284 	return (err);
1285 }
1286 
1287 
1288 /*
1289     struct vnop_link_args {
1290 	struct vnode *a_tdvp;
1291 	struct vnode *a_vp;
1292 	struct componentname *a_cnp;
1293     };
1294 */
1295 static int
1296 fuse_vnop_link(struct vop_link_args *ap)
1297 {
1298 	struct vnode *vp = ap->a_vp;
1299 	struct vnode *tdvp = ap->a_tdvp;
1300 	struct componentname *cnp = ap->a_cnp;
1301 
1302 	struct vattr *vap = VTOVA(vp);
1303 
1304 	struct fuse_dispatcher fdi;
1305 	struct fuse_entry_out *feo;
1306 	struct fuse_link_in fli;
1307 
1308 	int err;
1309 
1310 	if (fuse_isdeadfs(vp)) {
1311 		return ENXIO;
1312 	}
1313 	if (vnode_mount(tdvp) != vnode_mount(vp)) {
1314 		return EXDEV;
1315 	}
1316 
1317 	/*
1318 	 * This is a seatbelt check to protect naive userspace filesystems from
1319 	 * themselves and the limitations of the FUSE IPC protocol.  If a
1320 	 * filesystem does not allow attribute caching, assume it is capable of
1321 	 * validating that nlink does not overflow.
1322 	 */
1323 	if (vap != NULL && vap->va_nlink >= FUSE_LINK_MAX)
1324 		return EMLINK;
1325 	fli.oldnodeid = VTOI(vp);
1326 
1327 	fdisp_init(&fdi, 0);
1328 	fuse_internal_newentry_makerequest(vnode_mount(tdvp), VTOI(tdvp), cnp,
1329 	    FUSE_LINK, &fli, sizeof(fli), &fdi);
1330 	if ((err = fdisp_wait_answ(&fdi))) {
1331 		goto out;
1332 	}
1333 	feo = fdi.answ;
1334 
1335 	if (fli.oldnodeid != feo->nodeid) {
1336 		struct fuse_data *data = fuse_get_mpdata(vnode_mount(vp));
1337 		fuse_warn(data, FSESS_WARN_ILLEGAL_INODE,
1338 			"Assigned wrong inode for a hard link.");
1339 		fuse_vnode_clear_attr_cache(vp);
1340 		fuse_vnode_clear_attr_cache(tdvp);
1341 		err = EIO;
1342 		goto out;
1343 	}
1344 
1345 	err = fuse_internal_checkentry(feo, vnode_vtype(vp));
1346 	if (!err) {
1347 		/*
1348 		 * Purge the parent's attribute cache because the daemon
1349 		 * should've updated its mtime and ctime
1350 		 */
1351 		fuse_vnode_clear_attr_cache(tdvp);
1352 		fuse_internal_cache_attrs(vp, &feo->attr, feo->attr_valid,
1353 			feo->attr_valid_nsec, NULL, true);
1354 	}
1355 out:
1356 	fdisp_destroy(&fdi);
1357 	return err;
1358 }
1359 
1360 struct fuse_lookup_alloc_arg {
1361 	struct fuse_entry_out *feo;
1362 	struct componentname *cnp;
1363 	uint64_t nid;
1364 	enum vtype vtyp;
1365 };
1366 
1367 /* Callback for vn_get_ino */
1368 static int
1369 fuse_lookup_alloc(struct mount *mp, void *arg, int lkflags, struct vnode **vpp)
1370 {
1371 	struct fuse_lookup_alloc_arg *flaa = arg;
1372 
1373 	return fuse_vnode_get(mp, flaa->feo, flaa->nid, NULL, vpp, flaa->cnp,
1374 		flaa->vtyp);
1375 }
1376 
1377 SDT_PROBE_DEFINE3(fusefs, , vnops, cache_lookup,
1378 	"int", "struct timespec*", "struct timespec*");
1379 /*
1380     struct vnop_lookup_args {
1381 	struct vnodeop_desc *a_desc;
1382 	struct vnode *a_dvp;
1383 	struct vnode **a_vpp;
1384 	struct componentname *a_cnp;
1385     };
1386 */
1387 int
1388 fuse_vnop_lookup(struct vop_lookup_args *ap)
1389 {
1390 	struct vnode *dvp = ap->a_dvp;
1391 	struct vnode **vpp = ap->a_vpp;
1392 	struct componentname *cnp = ap->a_cnp;
1393 	struct thread *td = curthread;
1394 	struct ucred *cred = cnp->cn_cred;
1395 	struct timespec now;
1396 
1397 	int nameiop = cnp->cn_nameiop;
1398 	int flags = cnp->cn_flags;
1399 	int islastcn = flags & ISLASTCN;
1400 	struct mount *mp = vnode_mount(dvp);
1401 	struct fuse_data *data = fuse_get_mpdata(mp);
1402 	int default_permissions = data->dataflags & FSESS_DEFAULT_PERMISSIONS;
1403 	bool is_dot;
1404 
1405 	int err = 0;
1406 	int lookup_err = 0;
1407 	struct vnode *vp = NULL;
1408 
1409 	struct fuse_dispatcher fdi;
1410 	bool did_lookup = false;
1411 	struct fuse_entry_out *feo = NULL;
1412 	enum vtype vtyp;	/* vnode type of target */
1413 
1414 	uint64_t nid;
1415 
1416 	if (fuse_isdeadfs(dvp)) {
1417 		*vpp = NULL;
1418 		return ENXIO;
1419 	}
1420 	if (!vnode_isdir(dvp))
1421 		return ENOTDIR;
1422 
1423 	if (islastcn && vfs_isrdonly(mp) && (nameiop != LOOKUP))
1424 		return EROFS;
1425 
1426 	if ((cnp->cn_flags & NOEXECCHECK) != 0)
1427 		cnp->cn_flags &= ~NOEXECCHECK;
1428 	else if ((err = fuse_internal_access(dvp, VEXEC, td, cred)))
1429 		return err;
1430 
1431 	is_dot = cnp->cn_namelen == 1 && *(cnp->cn_nameptr) == '.';
1432 	if ((flags & ISDOTDOT) && !(data->dataflags & FSESS_EXPORT_SUPPORT))
1433 	{
1434 		if (!(VTOFUD(dvp)->flag & FN_PARENT_NID)) {
1435 			/*
1436 			 * Since the file system doesn't support ".." lookups,
1437 			 * we have no way to find this entry.
1438 			 */
1439 			return ESTALE;
1440 		}
1441 		nid = VTOFUD(dvp)->parent_nid;
1442 		if (nid == 0)
1443 			return ENOENT;
1444 		/* .. is obviously a directory */
1445 		vtyp = VDIR;
1446 	} else if (is_dot) {
1447 		nid = VTOI(dvp);
1448 		/* . is obviously a directory */
1449 		vtyp = VDIR;
1450 	} else {
1451 		struct timespec timeout;
1452 		int ncpticks; /* here to accommodate for API contract */
1453 
1454 		err = cache_lookup(dvp, vpp, cnp, &timeout, &ncpticks);
1455 		getnanouptime(&now);
1456 		SDT_PROBE3(fusefs, , vnops, cache_lookup, err, &timeout, &now);
1457 		switch (err) {
1458 		case -1:		/* positive match */
1459 			if (timespeccmp(&timeout, &now, >)) {
1460 				counter_u64_add(fuse_lookup_cache_hits, 1);
1461 			} else {
1462 				/* Cache timeout */
1463 				counter_u64_add(fuse_lookup_cache_misses, 1);
1464 				bintime_clear(
1465 					&VTOFUD(*vpp)->entry_cache_timeout);
1466 				cache_purge(*vpp);
1467 				if (dvp != *vpp)
1468 					vput(*vpp);
1469 				else
1470 					vrele(*vpp);
1471 				*vpp = NULL;
1472 				break;
1473 			}
1474 			return 0;
1475 
1476 		case 0:		/* no match in cache */
1477 			counter_u64_add(fuse_lookup_cache_misses, 1);
1478 			break;
1479 
1480 		case ENOENT:		/* negative match */
1481 			if (timespeccmp(&timeout, &now, <=)) {
1482 				/* Cache timeout */
1483 				cache_purge_negative(dvp);
1484 				break;
1485 			}
1486 			/* fall through */
1487 		default:
1488 			return err;
1489 		}
1490 
1491 		fdisp_init(&fdi, cnp->cn_namelen + 1);
1492 		fdisp_make(&fdi, FUSE_LOOKUP, mp, VTOI(dvp), td, cred);
1493 
1494 		memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
1495 		((char *)fdi.indata)[cnp->cn_namelen] = '\0';
1496 		lookup_err = fdisp_wait_answ(&fdi);
1497 		did_lookup = true;
1498 
1499 		if (!lookup_err) {
1500 			/* lookup call succeeded */
1501 			feo = (struct fuse_entry_out *)fdi.answ;
1502 			nid = feo->nodeid;
1503 			if (nid == 0) {
1504 				/* zero nodeid means ENOENT and cache it */
1505 				struct timespec timeout;
1506 
1507 				fdi.answ_stat = ENOENT;
1508 				lookup_err = ENOENT;
1509 				if (cnp->cn_flags & MAKEENTRY) {
1510 					fuse_validity_2_timespec(feo, &timeout);
1511 					/* Use the same entry_time for .. as for
1512 					 * the file itself.  That doesn't honor
1513 					 * exactly what the fuse server tells
1514 					 * us, but to do otherwise would require
1515 					 * another cache lookup at this point.
1516 					 */
1517 					struct timespec *dtsp = NULL;
1518 					cache_enter_time(dvp, *vpp, cnp,
1519 						&timeout, dtsp);
1520 				}
1521 			}
1522 			vtyp = IFTOVT(feo->attr.mode);
1523 		}
1524 		if (lookup_err && (!fdi.answ_stat || lookup_err != ENOENT)) {
1525 			fdisp_destroy(&fdi);
1526 			return lookup_err;
1527 		}
1528 	}
1529 	/* lookup_err, if non-zero, must be ENOENT at this point */
1530 
1531 	if (lookup_err) {
1532 		/* Entry not found */
1533 		if ((nameiop == CREATE || nameiop == RENAME) && islastcn) {
1534 			if (default_permissions)
1535 				err = fuse_internal_access(dvp, VWRITE, td,
1536 				    cred);
1537 			else
1538 				err = 0;
1539 			if (!err) {
1540 				err = EJUSTRETURN;
1541 			}
1542 		} else {
1543 			err = ENOENT;
1544 		}
1545 	} else {
1546 		/* Entry was found */
1547 		if (flags & ISDOTDOT) {
1548 			struct fuse_lookup_alloc_arg flaa;
1549 
1550 			flaa.nid = nid;
1551 			flaa.feo = feo;
1552 			flaa.cnp = cnp;
1553 			flaa.vtyp = vtyp;
1554 			err = vn_vget_ino_gen(dvp, fuse_lookup_alloc, &flaa, 0,
1555 				&vp);
1556 			*vpp = vp;
1557 		} else if (nid == VTOI(dvp)) {
1558 			if (is_dot) {
1559 				vref(dvp);
1560 				*vpp = dvp;
1561 			} else {
1562 				fuse_warn(fuse_get_mpdata(mp),
1563 				    FSESS_WARN_ILLEGAL_INODE,
1564 				    "Assigned same inode to both parent and "
1565 				    "child.");
1566 				err = EIO;
1567 			}
1568 
1569 		} else {
1570 			struct fuse_vnode_data *fvdat;
1571 
1572 			err = fuse_vnode_get(vnode_mount(dvp), feo, nid, dvp,
1573 			    &vp, cnp, vtyp);
1574 			if (err)
1575 				goto out;
1576 			*vpp = vp;
1577 			fvdat = VTOFUD(vp);
1578 
1579 			MPASS(feo != NULL);
1580 			if (timespeccmp(&now, &fvdat->last_local_modify, >)) {
1581 				/*
1582 				 * Attributes from the server are definitely
1583 				 * newer than the last attributes we sent to
1584 				 * the server, so cache them.
1585 				 */
1586 				fuse_internal_cache_attrs(*vpp, &feo->attr,
1587 					feo->attr_valid, feo->attr_valid_nsec,
1588 					NULL, true);
1589 			}
1590 			fuse_validity_2_bintime(feo->entry_valid,
1591 				feo->entry_valid_nsec,
1592 				&fvdat->entry_cache_timeout);
1593 
1594 			if ((nameiop == DELETE || nameiop == RENAME) &&
1595 				islastcn && default_permissions)
1596 			{
1597 				struct vattr dvattr;
1598 
1599 				err = fuse_internal_access(dvp, VWRITE, td,
1600 					cred);
1601 				if (err != 0)
1602 					goto out;
1603 				/*
1604 				 * if the parent's sticky bit is set, check
1605 				 * whether we're allowed to remove the file.
1606 				 * Need to figure out the vnode locking to make
1607 				 * this work.
1608 				 */
1609 				fuse_internal_getattr(dvp, &dvattr, cred, td);
1610 				if ((dvattr.va_mode & S_ISTXT) &&
1611 					fuse_internal_access(dvp, VADMIN, td,
1612 						cred) &&
1613 					fuse_internal_access(*vpp, VADMIN, td,
1614 						cred)) {
1615 					err = EPERM;
1616 					goto out;
1617 				}
1618 			}
1619 		}
1620 	}
1621 out:
1622 	if (err) {
1623 		if (vp != NULL && dvp != vp)
1624 			vput(vp);
1625 		else if (vp != NULL)
1626 			vrele(vp);
1627 		*vpp = NULL;
1628 	}
1629 	if (did_lookup)
1630 		fdisp_destroy(&fdi);
1631 
1632 	return err;
1633 }
1634 
1635 /*
1636     struct vnop_mkdir_args {
1637 	struct vnode *a_dvp;
1638 	struct vnode **a_vpp;
1639 	struct componentname *a_cnp;
1640 	struct vattr *a_vap;
1641     };
1642 */
1643 static int
1644 fuse_vnop_mkdir(struct vop_mkdir_args *ap)
1645 {
1646 	struct vnode *dvp = ap->a_dvp;
1647 	struct vnode **vpp = ap->a_vpp;
1648 	struct componentname *cnp = ap->a_cnp;
1649 	struct vattr *vap = ap->a_vap;
1650 
1651 	struct fuse_mkdir_in fmdi;
1652 
1653 	if (fuse_isdeadfs(dvp)) {
1654 		return ENXIO;
1655 	}
1656 	fmdi.mode = MAKEIMODE(vap->va_type, vap->va_mode);
1657 	fmdi.umask = curthread->td_proc->p_pd->pd_cmask;
1658 
1659 	return (fuse_internal_newentry(dvp, vpp, cnp, FUSE_MKDIR, &fmdi,
1660 	    sizeof(fmdi), VDIR));
1661 }
1662 
1663 /*
1664     struct vnop_mknod_args {
1665 	struct vnode *a_dvp;
1666 	struct vnode **a_vpp;
1667 	struct componentname *a_cnp;
1668 	struct vattr *a_vap;
1669     };
1670 */
1671 static int
1672 fuse_vnop_mknod(struct vop_mknod_args *ap)
1673 {
1674 
1675 	struct vnode *dvp = ap->a_dvp;
1676 	struct vnode **vpp = ap->a_vpp;
1677 	struct componentname *cnp = ap->a_cnp;
1678 	struct vattr *vap = ap->a_vap;
1679 
1680 	if (fuse_isdeadfs(dvp))
1681 		return ENXIO;
1682 
1683 	return fuse_internal_mknod(dvp, vpp, cnp, vap);
1684 }
1685 
1686 /*
1687     struct vop_open_args {
1688 	struct vnode *a_vp;
1689 	int  a_mode;
1690 	struct ucred *a_cred;
1691 	struct thread *a_td;
1692 	int a_fdidx; / struct file *a_fp;
1693     };
1694 */
1695 static int
1696 fuse_vnop_open(struct vop_open_args *ap)
1697 {
1698 	struct vnode *vp = ap->a_vp;
1699 	int a_mode = ap->a_mode;
1700 	struct thread *td = ap->a_td;
1701 	struct ucred *cred = ap->a_cred;
1702 	pid_t pid = td->td_proc->p_pid;
1703 
1704 	if (fuse_isdeadfs(vp))
1705 		return ENXIO;
1706 	if (vp->v_type == VCHR || vp->v_type == VBLK || vp->v_type == VFIFO)
1707 		return (EOPNOTSUPP);
1708 	if ((a_mode & (FREAD | FWRITE | FEXEC)) == 0)
1709 		return EINVAL;
1710 
1711 	if (fuse_filehandle_validrw(vp, a_mode, cred, pid)) {
1712 		fuse_vnode_open(vp, 0, td);
1713 		return 0;
1714 	}
1715 
1716 	return fuse_filehandle_open(vp, a_mode, NULL, td, cred);
1717 }
1718 
1719 static int
1720 fuse_vnop_pathconf(struct vop_pathconf_args *ap)
1721 {
1722 	struct vnode *vp = ap->a_vp;
1723 	struct mount *mp;
1724 
1725 	switch (ap->a_name) {
1726 	case _PC_FILESIZEBITS:
1727 		*ap->a_retval = 64;
1728 		return (0);
1729 	case _PC_NAME_MAX:
1730 		*ap->a_retval = NAME_MAX;
1731 		return (0);
1732 	case _PC_LINK_MAX:
1733 		*ap->a_retval = MIN(LONG_MAX, FUSE_LINK_MAX);
1734 		return (0);
1735 	case _PC_SYMLINK_MAX:
1736 		*ap->a_retval = MAXPATHLEN;
1737 		return (0);
1738 	case _PC_NO_TRUNC:
1739 		*ap->a_retval = 1;
1740 		return (0);
1741 	case _PC_MIN_HOLE_SIZE:
1742 		/*
1743 		 * The FUSE protocol provides no mechanism for a server to
1744 		 * report _PC_MIN_HOLE_SIZE.  It's a protocol bug.  Instead,
1745 		 * return EINVAL if the server does not support FUSE_LSEEK, or
1746 		 * 1 if it does.
1747 		 */
1748 		mp = vnode_mount(vp);
1749 		if (!fsess_is_impl(mp, FUSE_LSEEK) &&
1750 		    !fsess_not_impl(mp, FUSE_LSEEK)) {
1751 			off_t offset = 0;
1752 
1753 			/* Issue a FUSE_LSEEK to find out if it's implemented */
1754 			fuse_vnop_do_lseek(vp, curthread, curthread->td_ucred,
1755 			    curthread->td_proc->p_pid, &offset, SEEK_DATA);
1756 		}
1757 
1758 		if (fsess_is_impl(mp, FUSE_LSEEK)) {
1759 			*ap->a_retval = 1;
1760 			return (0);
1761 		} else {
1762 			/*
1763 			 * Probably FUSE_LSEEK is not implemented.  It might
1764 			 * be, if the FUSE_LSEEK above returned an error like
1765 			 * EACCES, but in that case we can't tell, so it's
1766 			 * safest to report EINVAL anyway.
1767 			 */
1768 			return (EINVAL);
1769 		}
1770 	default:
1771 		return (vop_stdpathconf(ap));
1772 	}
1773 }
1774 
1775 SDT_PROBE_DEFINE3(fusefs, , vnops, filehandles_closed, "struct vnode*",
1776     "struct uio*", "struct ucred*");
1777 /*
1778     struct vnop_read_args {
1779 	struct vnode *a_vp;
1780 	struct uio *a_uio;
1781 	int  a_ioflag;
1782 	struct ucred *a_cred;
1783     };
1784 */
1785 static int
1786 fuse_vnop_read(struct vop_read_args *ap)
1787 {
1788 	struct vnode *vp = ap->a_vp;
1789 	struct uio *uio = ap->a_uio;
1790 	int ioflag = ap->a_ioflag;
1791 	struct ucred *cred = ap->a_cred;
1792 	pid_t pid = curthread->td_proc->p_pid;
1793 	struct fuse_filehandle *fufh;
1794 	int err;
1795 	bool closefufh = false, directio;
1796 
1797 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
1798 
1799 	if (fuse_isdeadfs(vp)) {
1800 		return ENXIO;
1801 	}
1802 
1803 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
1804 		ioflag |= IO_DIRECT;
1805 	}
1806 
1807 	err = fuse_filehandle_getrw(vp, FREAD, &fufh, cred, pid);
1808 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
1809 		/*
1810 		 * nfsd will do I/O without first doing VOP_OPEN.  We
1811 		 * must implicitly open the file here
1812 		 */
1813 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1814 		closefufh = true;
1815 	}
1816 	if (err) {
1817 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
1818 		return err;
1819 	}
1820 
1821 	/*
1822          * Ideally, when the daemon asks for direct io at open time, the
1823          * standard file flag should be set according to this, so that would
1824          * just change the default mode, which later on could be changed via
1825          * fcntl(2).
1826          * But this doesn't work, the O_DIRECT flag gets cleared at some point
1827          * (don't know where). So to make any use of the Fuse direct_io option,
1828          * we hardwire it into the file's private data (similarly to Linux,
1829          * btw.).
1830          */
1831 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
1832 
1833 	fuse_vnode_update(vp, FN_ATIMECHANGE);
1834 	if (directio) {
1835 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct read of vnode");
1836 		err = fuse_read_directbackend(vp, uio, cred, fufh);
1837 	} else {
1838 		SDT_PROBE2(fusefs, , vnops, trace, 1, "buffered read of vnode");
1839 		err = fuse_read_biobackend(vp, uio, ioflag, cred, fufh, pid);
1840 	}
1841 
1842 	if (closefufh)
1843 		fuse_filehandle_close(vp, fufh, curthread, cred);
1844 
1845 	return (err);
1846 }
1847 
1848 /*
1849     struct vnop_readdir_args {
1850 	struct vnode *a_vp;
1851 	struct uio *a_uio;
1852 	struct ucred *a_cred;
1853 	int *a_eofflag;
1854 	int *a_ncookies;
1855 	uint64_t **a_cookies;
1856     };
1857 */
1858 static int
1859 fuse_vnop_readdir(struct vop_readdir_args *ap)
1860 {
1861 	struct vnode *vp = ap->a_vp;
1862 	struct uio *uio = ap->a_uio;
1863 	struct ucred *cred = ap->a_cred;
1864 	struct fuse_filehandle *fufh = NULL;
1865 	struct mount *mp = vnode_mount(vp);
1866 	struct fuse_iov cookediov;
1867 	int err = 0;
1868 	uint64_t *cookies;
1869 	ssize_t tresid;
1870 	int ncookies;
1871 	bool closefufh = false;
1872 	pid_t pid = curthread->td_proc->p_pid;
1873 
1874 	if (ap->a_eofflag)
1875 		*ap->a_eofflag = 0;
1876 	if (fuse_isdeadfs(vp)) {
1877 		return ENXIO;
1878 	}
1879 	if (				/* XXXIP ((uio_iovcnt(uio) > 1)) || */
1880 	    (uio_resid(uio) < sizeof(struct dirent))) {
1881 		return EINVAL;
1882 	}
1883 
1884 	tresid = uio->uio_resid;
1885 	err = fuse_filehandle_get_dir(vp, &fufh, cred, pid);
1886 	if (err == EBADF && mp->mnt_flag & MNT_EXPORTED) {
1887 		KASSERT(fuse_get_mpdata(mp)->dataflags
1888 				& FSESS_NO_OPENDIR_SUPPORT,
1889 			("FUSE file systems that don't set "
1890 			 "FUSE_NO_OPENDIR_SUPPORT should not be exported"));
1891 		/*
1892 		 * nfsd will do VOP_READDIR without first doing VOP_OPEN.  We
1893 		 * must implicitly open the directory here.
1894 		 */
1895 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1896 		closefufh = true;
1897 	}
1898 	if (err)
1899 		return (err);
1900 	if (ap->a_ncookies != NULL) {
1901 		ncookies = uio->uio_resid /
1902 			(offsetof(struct dirent, d_name) + 4) + 1;
1903 		cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
1904 		*ap->a_ncookies = ncookies;
1905 		*ap->a_cookies = cookies;
1906 	} else {
1907 		ncookies = 0;
1908 		cookies = NULL;
1909 	}
1910 #define DIRCOOKEDSIZE FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + MAXNAMLEN + 1)
1911 	fiov_init(&cookediov, DIRCOOKEDSIZE);
1912 
1913 	err = fuse_internal_readdir(vp, uio, fufh, &cookediov,
1914 		&ncookies, cookies);
1915 
1916 	fiov_teardown(&cookediov);
1917 	if (closefufh)
1918 		fuse_filehandle_close(vp, fufh, curthread, cred);
1919 
1920 	if (ap->a_ncookies != NULL) {
1921 		if (err == 0) {
1922 			*ap->a_ncookies -= ncookies;
1923 		} else {
1924 			free(*ap->a_cookies, M_TEMP);
1925 			*ap->a_ncookies = 0;
1926 			*ap->a_cookies = NULL;
1927 		}
1928 	}
1929 	if (err == 0 && tresid == uio->uio_resid)
1930 		*ap->a_eofflag = 1;
1931 
1932 	return err;
1933 }
1934 
1935 /*
1936     struct vnop_readlink_args {
1937 	struct vnode *a_vp;
1938 	struct uio *a_uio;
1939 	struct ucred *a_cred;
1940     };
1941 */
1942 static int
1943 fuse_vnop_readlink(struct vop_readlink_args *ap)
1944 {
1945 	struct vnode *vp = ap->a_vp;
1946 	struct uio *uio = ap->a_uio;
1947 	struct ucred *cred = ap->a_cred;
1948 
1949 	struct fuse_dispatcher fdi;
1950 	int err;
1951 
1952 	if (fuse_isdeadfs(vp)) {
1953 		return ENXIO;
1954 	}
1955 	if (!vnode_islnk(vp)) {
1956 		return EINVAL;
1957 	}
1958 	fdisp_init(&fdi, 0);
1959 	err = fdisp_simple_putget_vp(&fdi, FUSE_READLINK, vp, curthread, cred);
1960 	if (err) {
1961 		goto out;
1962 	}
1963 	if (((char *)fdi.answ)[0] == '/' &&
1964 	    fuse_get_mpdata(vnode_mount(vp))->dataflags & FSESS_PUSH_SYMLINKS_IN) {
1965 		char *mpth = vnode_mount(vp)->mnt_stat.f_mntonname;
1966 
1967 		err = uiomove(mpth, strlen(mpth), uio);
1968 	}
1969 	if (!err) {
1970 		err = uiomove(fdi.answ, fdi.iosize, uio);
1971 	}
1972 out:
1973 	fdisp_destroy(&fdi);
1974 	return err;
1975 }
1976 
1977 /*
1978     struct vnop_reclaim_args {
1979 	struct vnode *a_vp;
1980     };
1981 */
1982 static int
1983 fuse_vnop_reclaim(struct vop_reclaim_args *ap)
1984 {
1985 	struct vnode *vp = ap->a_vp;
1986 	struct thread *td = curthread;
1987 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1988 	struct fuse_filehandle *fufh, *fufh_tmp;
1989 
1990 	if (!fvdat) {
1991 		panic("FUSE: no vnode data during recycling");
1992 	}
1993 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1994 		printf("FUSE: vnode being reclaimed with open fufh "
1995 			"(type=%#x)", fufh->fufh_type);
1996 		fuse_filehandle_close(vp, fufh, td, NULL);
1997 	}
1998 
1999 	if (VTOI(vp) == 1) {
2000 		/*
2001 		 * Don't send FUSE_FORGET for the root inode, because
2002 		 * we never send FUSE_LOOKUP for it (see
2003 		 * fuse_vfsop_root) and we don't want the server to see
2004 		 * mismatched lookup counts.
2005 		 */
2006 		struct fuse_data *data;
2007 		struct vnode *vroot;
2008 
2009 		data = fuse_get_mpdata(vnode_mount(vp));
2010 		FUSE_LOCK();
2011 		vroot = data->vroot;
2012 		data->vroot = NULL;
2013 		FUSE_UNLOCK();
2014 		if (vroot)
2015 			vrele(vroot);
2016 	} else if (!fuse_isdeadfs(vp) && fvdat->nlookup > 0) {
2017 		fuse_internal_forget_send(vnode_mount(vp), td, NULL, VTOI(vp),
2018 		    fvdat->nlookup);
2019 	}
2020 	cache_purge(vp);
2021 	vfs_hash_remove(vp);
2022 	fuse_vnode_destroy(vp);
2023 
2024 	return 0;
2025 }
2026 
2027 /*
2028     struct vnop_remove_args {
2029 	struct vnode *a_dvp;
2030 	struct vnode *a_vp;
2031 	struct componentname *a_cnp;
2032     };
2033 */
2034 static int
2035 fuse_vnop_remove(struct vop_remove_args *ap)
2036 {
2037 	struct vnode *dvp = ap->a_dvp;
2038 	struct vnode *vp = ap->a_vp;
2039 	struct componentname *cnp = ap->a_cnp;
2040 
2041 	int err;
2042 
2043 	if (fuse_isdeadfs(vp)) {
2044 		return ENXIO;
2045 	}
2046 	if (vnode_isdir(vp)) {
2047 		return EPERM;
2048 	}
2049 
2050 	err = fuse_internal_remove(dvp, vp, cnp, FUSE_UNLINK);
2051 
2052 	return err;
2053 }
2054 
2055 /*
2056     struct vnop_rename_args {
2057 	struct vnode *a_fdvp;
2058 	struct vnode *a_fvp;
2059 	struct componentname *a_fcnp;
2060 	struct vnode *a_tdvp;
2061 	struct vnode *a_tvp;
2062 	struct componentname *a_tcnp;
2063     };
2064 */
2065 static int
2066 fuse_vnop_rename(struct vop_rename_args *ap)
2067 {
2068 	struct vnode *fdvp = ap->a_fdvp;
2069 	struct vnode *fvp = ap->a_fvp;
2070 	struct componentname *fcnp = ap->a_fcnp;
2071 	struct vnode *tdvp = ap->a_tdvp;
2072 	struct vnode *tvp = ap->a_tvp;
2073 	struct componentname *tcnp = ap->a_tcnp;
2074 	struct fuse_data *data;
2075 	bool newparent = fdvp != tdvp;
2076 	bool isdir = fvp->v_type == VDIR;
2077 	int err = 0;
2078 
2079 	if (fuse_isdeadfs(fdvp)) {
2080 		return ENXIO;
2081 	}
2082 	if (fvp->v_mount != tdvp->v_mount ||
2083 	    (tvp && fvp->v_mount != tvp->v_mount)) {
2084 		SDT_PROBE2(fusefs, , vnops, trace, 1, "cross-device rename");
2085 		err = EXDEV;
2086 		goto out;
2087 	}
2088 	cache_purge(fvp);
2089 
2090 	/*
2091 	 * FUSE library is expected to check if target directory is not
2092 	 * under the source directory in the file system tree.
2093 	 * Linux performs this check at VFS level.
2094 	 */
2095 	/*
2096 	 * If source is a directory, and it will get a new parent, user must
2097 	 * have write permission to it, so ".." can be modified.
2098 	 */
2099 	data = fuse_get_mpdata(vnode_mount(tdvp));
2100 	if (data->dataflags & FSESS_DEFAULT_PERMISSIONS && isdir && newparent) {
2101 		err = fuse_internal_access(fvp, VWRITE,
2102 			curthread, tcnp->cn_cred);
2103 		if (err)
2104 			goto out;
2105 	}
2106 	sx_xlock(&data->rename_lock);
2107 	err = fuse_internal_rename(fdvp, fcnp, tdvp, tcnp);
2108 	if (err == 0) {
2109 		if (tdvp != fdvp)
2110 			fuse_vnode_setparent(fvp, tdvp);
2111 		if (tvp != NULL)
2112 			fuse_vnode_setparent(tvp, NULL);
2113 	}
2114 	sx_unlock(&data->rename_lock);
2115 
2116 	if (tvp != NULL && tvp != fvp) {
2117 		cache_purge(tvp);
2118 	}
2119 	if (vnode_isdir(fvp)) {
2120 		if (((tvp != NULL) && vnode_isdir(tvp)) || vnode_isdir(fvp)) {
2121 			cache_purge(tdvp);
2122 		}
2123 		cache_purge(fdvp);
2124 	}
2125 out:
2126 	if (tdvp == tvp) {
2127 		vrele(tdvp);
2128 	} else {
2129 		vput(tdvp);
2130 	}
2131 	if (tvp != NULL) {
2132 		vput(tvp);
2133 	}
2134 	vrele(fdvp);
2135 	vrele(fvp);
2136 
2137 	return err;
2138 }
2139 
2140 /*
2141     struct vnop_rmdir_args {
2142 	    struct vnode *a_dvp;
2143 	    struct vnode *a_vp;
2144 	    struct componentname *a_cnp;
2145     } *ap;
2146 */
2147 static int
2148 fuse_vnop_rmdir(struct vop_rmdir_args *ap)
2149 {
2150 	struct vnode *dvp = ap->a_dvp;
2151 	struct vnode *vp = ap->a_vp;
2152 
2153 	int err;
2154 
2155 	if (fuse_isdeadfs(vp)) {
2156 		return ENXIO;
2157 	}
2158 	if (VTOFUD(vp) == VTOFUD(dvp)) {
2159 		return EINVAL;
2160 	}
2161 	err = fuse_internal_remove(dvp, vp, ap->a_cnp, FUSE_RMDIR);
2162 
2163 	return err;
2164 }
2165 
2166 /*
2167     struct vnop_setattr_args {
2168 	struct vnode *a_vp;
2169 	struct vattr *a_vap;
2170 	struct ucred *a_cred;
2171 	struct thread *a_td;
2172     };
2173 */
2174 static int
2175 fuse_vnop_setattr(struct vop_setattr_args *ap)
2176 {
2177 	struct vnode *vp = ap->a_vp;
2178 	struct vattr *vap = ap->a_vap;
2179 	struct ucred *cred = ap->a_cred;
2180 	struct thread *td = curthread;
2181 	struct mount *mp;
2182 	struct fuse_data *data;
2183 	struct vattr old_va;
2184 	int dataflags;
2185 	int err = 0, err2;
2186 	accmode_t accmode = 0;
2187 	bool checkperm;
2188 	bool drop_suid = false;
2189 	gid_t cr_gid;
2190 
2191 	mp = vnode_mount(vp);
2192 	data = fuse_get_mpdata(mp);
2193 	dataflags = data->dataflags;
2194 	checkperm = dataflags & FSESS_DEFAULT_PERMISSIONS;
2195 	if (cred->cr_ngroups > 0)
2196 		cr_gid = cred->cr_groups[0];
2197 	else
2198 		cr_gid = 0;
2199 
2200 	if (fuse_isdeadfs(vp)) {
2201 		return ENXIO;
2202 	}
2203 
2204 	if (vap->va_uid != (uid_t)VNOVAL) {
2205 		if (checkperm) {
2206 			/* Only root may change a file's owner */
2207 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2208 			if (err) {
2209 				/* As a special case, allow the null chown */
2210 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2211 					td);
2212 				if (err2)
2213 					return (err2);
2214 				if (vap->va_uid != old_va.va_uid)
2215 					return err;
2216 				else
2217 					accmode |= VADMIN;
2218 				drop_suid = true;
2219 			} else
2220 				accmode |= VADMIN;
2221 		} else
2222 			accmode |= VADMIN;
2223 	}
2224 	if (vap->va_gid != (gid_t)VNOVAL) {
2225 		if (checkperm && priv_check_cred(cred, PRIV_VFS_CHOWN))
2226 			drop_suid = true;
2227 		if (checkperm && !groupmember(vap->va_gid, cred))
2228 		{
2229 			/*
2230 			 * Non-root users may only chgrp to one of their own
2231 			 * groups
2232 			 */
2233 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2234 			if (err) {
2235 				/* As a special case, allow the null chgrp */
2236 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2237 					td);
2238 				if (err2)
2239 					return (err2);
2240 				if (vap->va_gid != old_va.va_gid)
2241 					return err;
2242 				accmode |= VADMIN;
2243 			} else
2244 				accmode |= VADMIN;
2245 		} else
2246 			accmode |= VADMIN;
2247 	}
2248 	if (vap->va_size != VNOVAL) {
2249 		switch (vp->v_type) {
2250 		case VDIR:
2251 			return (EISDIR);
2252 		case VLNK:
2253 		case VREG:
2254 			if (vfs_isrdonly(mp))
2255 				return (EROFS);
2256 			err = vn_rlimit_trunc(vap->va_size, td);
2257 			if (err)
2258 				return (err);
2259 			break;
2260 		default:
2261 			/*
2262 			 * According to POSIX, the result is unspecified
2263 			 * for file types other than regular files,
2264 			 * directories and shared memory objects.  We
2265 			 * don't support shared memory objects in the file
2266 			 * system, and have dubious support for truncating
2267 			 * symlinks.  Just ignore the request in other cases.
2268 			 */
2269 			return (0);
2270 		}
2271 		/* Don't set accmode.  Permission to trunc is checked upstack */
2272 	}
2273 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
2274 		if (vap->va_vaflags & VA_UTIMES_NULL)
2275 			accmode |= VWRITE;
2276 		else
2277 			accmode |= VADMIN;
2278 	}
2279 	if (drop_suid) {
2280 		if (vap->va_mode != (mode_t)VNOVAL)
2281 			vap->va_mode &= ~(S_ISUID | S_ISGID);
2282 		else {
2283 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2284 			if (err)
2285 				return (err);
2286 			vap->va_mode = old_va.va_mode & ~(S_ISUID | S_ISGID);
2287 		}
2288 	}
2289 	if (vap->va_mode != (mode_t)VNOVAL) {
2290 		/* Only root may set the sticky bit on non-directories */
2291 		if (checkperm && vp->v_type != VDIR && (vap->va_mode & S_ISTXT)
2292 		    && priv_check_cred(cred, PRIV_VFS_STICKYFILE))
2293 			return EFTYPE;
2294 		if (checkperm && (vap->va_mode & S_ISGID)) {
2295 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2296 			if (err)
2297 				return (err);
2298 			if (!groupmember(old_va.va_gid, cred)) {
2299 				err = priv_check_cred(cred, PRIV_VFS_SETGID);
2300 				if (err)
2301 					return (err);
2302 			}
2303 		}
2304 		accmode |= VADMIN;
2305 	}
2306 
2307 	if (vfs_isrdonly(mp))
2308 		return EROFS;
2309 
2310 	if (checkperm) {
2311 		err = fuse_internal_access(vp, accmode, td, cred);
2312 	} else {
2313 		err = 0;
2314 	}
2315 	if (err)
2316 		return err;
2317 	else
2318 		return fuse_internal_setattr(vp, vap, td, cred);
2319 }
2320 
2321 /*
2322     struct vnop_strategy_args {
2323 	struct vnode *a_vp;
2324 	struct buf *a_bp;
2325     };
2326 */
2327 static int
2328 fuse_vnop_strategy(struct vop_strategy_args *ap)
2329 {
2330 	struct vnode *vp = ap->a_vp;
2331 	struct buf *bp = ap->a_bp;
2332 
2333 	if (!vp || fuse_isdeadfs(vp)) {
2334 		bp->b_ioflags |= BIO_ERROR;
2335 		bp->b_error = ENXIO;
2336 		bufdone(bp);
2337 		return 0;
2338 	}
2339 
2340 	/*
2341 	 * VOP_STRATEGY always returns zero and signals error via bp->b_ioflags.
2342 	 * fuse_io_strategy sets bp's error fields
2343 	 */
2344 	(void)fuse_io_strategy(vp, bp);
2345 
2346 	return 0;
2347 }
2348 
2349 /*
2350     struct vnop_symlink_args {
2351 	struct vnode *a_dvp;
2352 	struct vnode **a_vpp;
2353 	struct componentname *a_cnp;
2354 	struct vattr *a_vap;
2355 	char *a_target;
2356     };
2357 */
2358 static int
2359 fuse_vnop_symlink(struct vop_symlink_args *ap)
2360 {
2361 	struct vnode *dvp = ap->a_dvp;
2362 	struct vnode **vpp = ap->a_vpp;
2363 	struct componentname *cnp = ap->a_cnp;
2364 	const char *target = ap->a_target;
2365 
2366 	struct fuse_dispatcher fdi;
2367 
2368 	int err;
2369 	size_t len;
2370 
2371 	if (fuse_isdeadfs(dvp)) {
2372 		return ENXIO;
2373 	}
2374 	/*
2375 	 * Unlike the other creator type calls, here we have to create a message
2376 	 * where the name of the new entry comes first, and the data describing
2377 	 * the entry comes second.
2378 	 * Hence we can't rely on our handy fuse_internal_newentry() routine,
2379 	 * but put together the message manually and just call the core part.
2380 	 */
2381 
2382 	len = strlen(target) + 1;
2383 	fdisp_init(&fdi, len + cnp->cn_namelen + 1);
2384 	fdisp_make_vp(&fdi, FUSE_SYMLINK, dvp, curthread, NULL);
2385 
2386 	memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
2387 	((char *)fdi.indata)[cnp->cn_namelen] = '\0';
2388 	memcpy((char *)fdi.indata + cnp->cn_namelen + 1, target, len);
2389 
2390 	err = fuse_internal_newentry_core(dvp, vpp, cnp, VLNK, &fdi);
2391 	fdisp_destroy(&fdi);
2392 	return err;
2393 }
2394 
2395 /*
2396     struct vnop_write_args {
2397 	struct vnode *a_vp;
2398 	struct uio *a_uio;
2399 	int  a_ioflag;
2400 	struct ucred *a_cred;
2401     };
2402 */
2403 static int
2404 fuse_vnop_write(struct vop_write_args *ap)
2405 {
2406 	struct vnode *vp = ap->a_vp;
2407 	struct uio *uio = ap->a_uio;
2408 	int ioflag = ap->a_ioflag;
2409 	struct ucred *cred = ap->a_cred;
2410 	pid_t pid = curthread->td_proc->p_pid;
2411 	struct fuse_filehandle *fufh;
2412 	int err;
2413 	bool closefufh = false, directio;
2414 
2415 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
2416 
2417 	if (fuse_isdeadfs(vp)) {
2418 		return ENXIO;
2419 	}
2420 
2421 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
2422 		ioflag |= IO_DIRECT;
2423 	}
2424 
2425 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2426 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2427 		/*
2428 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2429 		 * must implicitly open the file here
2430 		 */
2431 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2432 		closefufh = true;
2433 	}
2434 	if (err) {
2435 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
2436 		return err;
2437 	}
2438 
2439 	/*
2440          * Ideally, when the daemon asks for direct io at open time, the
2441          * standard file flag should be set according to this, so that would
2442          * just change the default mode, which later on could be changed via
2443          * fcntl(2).
2444          * But this doesn't work, the O_DIRECT flag gets cleared at some point
2445          * (don't know where). So to make any use of the Fuse direct_io option,
2446          * we hardwire it into the file's private data (similarly to Linux,
2447          * btw.).
2448          */
2449 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
2450 
2451 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2452 	if (directio) {
2453 		off_t start, end, filesize;
2454 		bool pages = (ioflag & IO_VMIO) != 0;
2455 
2456 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct write of vnode");
2457 
2458 		err = fuse_vnode_size(vp, &filesize, cred, curthread);
2459 		if (err)
2460 			goto out;
2461 
2462 		start = uio->uio_offset;
2463 		end = start + uio->uio_resid;
2464 		if (!pages) {
2465 			err = fuse_inval_buf_range(vp, filesize, start,
2466 			    end);
2467 			if (err)
2468 				goto out;
2469 		}
2470 		err = fuse_write_directbackend(vp, uio, cred, fufh,
2471 			filesize, ioflag, pages);
2472 	} else {
2473 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2474 			"buffered write of vnode");
2475 		if (!fsess_opt_writeback(vnode_mount(vp)))
2476 			ioflag |= IO_SYNC;
2477 		err = fuse_write_biobackend(vp, uio, cred, fufh, ioflag, pid);
2478 	}
2479 	fuse_internal_clear_suid_on_write(vp, cred, uio->uio_td);
2480 
2481 out:
2482 	if (closefufh)
2483 		fuse_filehandle_close(vp, fufh, curthread, cred);
2484 
2485 	return (err);
2486 }
2487 
2488 static daddr_t
2489 fuse_gbp_getblkno(struct vnode *vp, vm_ooffset_t off)
2490 {
2491 	const int biosize = fuse_iosize(vp);
2492 
2493 	return (off / biosize);
2494 }
2495 
2496 static int
2497 fuse_gbp_getblksz(struct vnode *vp, daddr_t lbn, long *blksz)
2498 {
2499 	off_t filesize;
2500 	int err;
2501 	const int biosize = fuse_iosize(vp);
2502 
2503 	err = fuse_vnode_size(vp, &filesize, NULL, NULL);
2504 	if (err) {
2505 		/* This will turn into a SIGBUS */
2506 		return (EIO);
2507 	} else if ((off_t)lbn * biosize >= filesize) {
2508 		*blksz = 0;
2509 	} else if ((off_t)(lbn + 1) * biosize > filesize) {
2510 		*blksz = filesize - (off_t)lbn *biosize;
2511 	} else {
2512 		*blksz = biosize;
2513 	}
2514 	return (0);
2515 }
2516 
2517 /*
2518     struct vnop_getpages_args {
2519 	struct vnode *a_vp;
2520 	vm_page_t *a_m;
2521 	int a_count;
2522 	int a_reqpage;
2523     };
2524 */
2525 static int
2526 fuse_vnop_getpages(struct vop_getpages_args *ap)
2527 {
2528 	struct vnode *vp = ap->a_vp;
2529 
2530 	if (!fsess_opt_mmap(vnode_mount(vp))) {
2531 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2532 			"called on non-cacheable vnode??\n");
2533 		return (VM_PAGER_ERROR);
2534 	}
2535 
2536 	return (vfs_bio_getpages(vp, ap->a_m, ap->a_count, ap->a_rbehind,
2537 	    ap->a_rahead, fuse_gbp_getblkno, fuse_gbp_getblksz));
2538 }
2539 
2540 static const char extattr_namespace_separator = '.';
2541 
2542 /*
2543     struct vop_getextattr_args {
2544 	struct vop_generic_args a_gen;
2545 	struct vnode *a_vp;
2546 	int a_attrnamespace;
2547 	const char *a_name;
2548 	struct uio *a_uio;
2549 	size_t *a_size;
2550 	struct ucred *a_cred;
2551 	struct thread *a_td;
2552     };
2553 */
2554 static int
2555 fuse_vnop_getextattr(struct vop_getextattr_args *ap)
2556 {
2557 	struct vnode *vp = ap->a_vp;
2558 	struct uio *uio = ap->a_uio;
2559 	struct fuse_dispatcher fdi;
2560 	struct fuse_getxattr_in *get_xattr_in;
2561 	struct fuse_getxattr_out *get_xattr_out;
2562 	struct mount *mp = vnode_mount(vp);
2563 	struct thread *td = ap->a_td;
2564 	struct ucred *cred = ap->a_cred;
2565 	char *prefix;
2566 	char *attr_str;
2567 	size_t len;
2568 	int err;
2569 
2570 	if (fuse_isdeadfs(vp))
2571 		return (ENXIO);
2572 
2573 	if (fsess_not_impl(mp, FUSE_GETXATTR))
2574 		return EOPNOTSUPP;
2575 
2576 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2577 	if (err)
2578 		return err;
2579 
2580 	/* Default to looking for user attributes. */
2581 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2582 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2583 	else
2584 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2585 
2586 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2587 	    strlen(ap->a_name) + 1;
2588 
2589 	fdisp_init(&fdi, len + sizeof(*get_xattr_in));
2590 	fdisp_make_vp(&fdi, FUSE_GETXATTR, vp, td, cred);
2591 
2592 	get_xattr_in = fdi.indata;
2593 	/*
2594 	 * Check to see whether we're querying the available size or
2595 	 * issuing the actual request.  If we pass in 0, we get back struct
2596 	 * fuse_getxattr_out.  If we pass in a non-zero size, we get back
2597 	 * that much data, without the struct fuse_getxattr_out header.
2598 	 */
2599 	if (uio == NULL)
2600 		get_xattr_in->size = 0;
2601 	else
2602 		get_xattr_in->size = uio->uio_resid;
2603 
2604 	attr_str = (char *)fdi.indata + sizeof(*get_xattr_in);
2605 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2606 	    ap->a_name);
2607 
2608 	err = fdisp_wait_answ(&fdi);
2609 	if (err != 0) {
2610 		if (err == ENOSYS) {
2611 			fsess_set_notimpl(mp, FUSE_GETXATTR);
2612 			err = EOPNOTSUPP;
2613 		}
2614 		goto out;
2615 	}
2616 
2617 	get_xattr_out = fdi.answ;
2618 
2619 	if (ap->a_size != NULL)
2620 		*ap->a_size = get_xattr_out->size;
2621 
2622 	if (uio != NULL)
2623 		err = uiomove(fdi.answ, fdi.iosize, uio);
2624 
2625 out:
2626 	fdisp_destroy(&fdi);
2627 	return (err);
2628 }
2629 
2630 /*
2631     struct vop_setextattr_args {
2632 	struct vop_generic_args a_gen;
2633 	struct vnode *a_vp;
2634 	int a_attrnamespace;
2635 	const char *a_name;
2636 	struct uio *a_uio;
2637 	struct ucred *a_cred;
2638 	struct thread *a_td;
2639     };
2640 */
2641 static int
2642 fuse_vnop_setextattr(struct vop_setextattr_args *ap)
2643 {
2644 	struct vnode *vp = ap->a_vp;
2645 	struct uio *uio = ap->a_uio;
2646 	struct fuse_dispatcher fdi;
2647 	struct fuse_setxattr_in *set_xattr_in;
2648 	struct mount *mp = vnode_mount(vp);
2649 	struct thread *td = ap->a_td;
2650 	struct ucred *cred = ap->a_cred;
2651 	char *prefix;
2652 	size_t len;
2653 	char *attr_str;
2654 	int err;
2655 
2656 	if (fuse_isdeadfs(vp))
2657 		return (ENXIO);
2658 
2659 	if (fsess_not_impl(mp, FUSE_SETXATTR))
2660 		return EOPNOTSUPP;
2661 
2662 	if (vfs_isrdonly(mp))
2663 		return EROFS;
2664 
2665 	/* Deleting xattrs must use VOP_DELETEEXTATTR instead */
2666 	if (ap->a_uio == NULL) {
2667 		/*
2668 		 * If we got here as fallback from VOP_DELETEEXTATTR, then
2669 		 * return EOPNOTSUPP.
2670 		 */
2671 		if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
2672 			return (EOPNOTSUPP);
2673 		else
2674 			return (EINVAL);
2675 	}
2676 
2677 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
2678 		VWRITE);
2679 	if (err)
2680 		return err;
2681 
2682 	/* Default to looking for user attributes. */
2683 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2684 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2685 	else
2686 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2687 
2688 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2689 	    strlen(ap->a_name) + 1;
2690 
2691 	fdisp_init(&fdi, len + sizeof(*set_xattr_in) + uio->uio_resid);
2692 	fdisp_make_vp(&fdi, FUSE_SETXATTR, vp, td, cred);
2693 
2694 	set_xattr_in = fdi.indata;
2695 	set_xattr_in->size = uio->uio_resid;
2696 
2697 	attr_str = (char *)fdi.indata + sizeof(*set_xattr_in);
2698 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2699 	    ap->a_name);
2700 
2701 	err = uiomove((char *)fdi.indata + sizeof(*set_xattr_in) + len,
2702 	    uio->uio_resid, uio);
2703 	if (err != 0) {
2704 		goto out;
2705 	}
2706 
2707 	err = fdisp_wait_answ(&fdi);
2708 
2709 	if (err == ENOSYS) {
2710 		fsess_set_notimpl(mp, FUSE_SETXATTR);
2711 		err = EOPNOTSUPP;
2712 	}
2713 	if (err == ERESTART) {
2714 		/* Can't restart after calling uiomove */
2715 		err = EINTR;
2716 	}
2717 
2718 out:
2719 	fdisp_destroy(&fdi);
2720 	return (err);
2721 }
2722 
2723 /*
2724  * The Linux / FUSE extended attribute list is simply a collection of
2725  * NUL-terminated strings.  The FreeBSD extended attribute list is a single
2726  * byte length followed by a non-NUL terminated string.  So, this allows
2727  * conversion of the Linux / FUSE format to the FreeBSD format in place.
2728  * Linux attribute names are reported with the namespace as a prefix (e.g.
2729  * "user.attribute_name"), but in FreeBSD they are reported without the
2730  * namespace prefix (e.g. "attribute_name").  So, we're going from:
2731  *
2732  * user.attr_name1\0user.attr_name2\0
2733  *
2734  * to:
2735  *
2736  * <num>attr_name1<num>attr_name2
2737  *
2738  * Where "<num>" is a single byte number of characters in the attribute name.
2739  *
2740  * Args:
2741  * prefix - exattr namespace prefix string
2742  * list, list_len - input list with namespace prefixes
2743  * bsd_list, bsd_list_len - output list compatible with bsd vfs
2744  */
2745 static int
2746 fuse_xattrlist_convert(char *prefix, const char *list, int list_len,
2747     char *bsd_list, int *bsd_list_len)
2748 {
2749 	int len, pos, dist_to_next, prefix_len;
2750 
2751 	pos = 0;
2752 	*bsd_list_len = 0;
2753 	prefix_len = strlen(prefix);
2754 
2755 	while (pos < list_len && list[pos] != '\0') {
2756 		dist_to_next = strlen(&list[pos]) + 1;
2757 		if (bcmp(&list[pos], prefix, prefix_len) == 0 &&
2758 		    list[pos + prefix_len] == extattr_namespace_separator) {
2759 			len = dist_to_next -
2760 			    (prefix_len + sizeof(extattr_namespace_separator)) - 1;
2761 			if (len >= EXTATTR_MAXNAMELEN)
2762 				return (ENAMETOOLONG);
2763 
2764 			bsd_list[*bsd_list_len] = len;
2765 			memcpy(&bsd_list[*bsd_list_len + 1],
2766 			    &list[pos + prefix_len +
2767 			    sizeof(extattr_namespace_separator)], len);
2768 
2769 			*bsd_list_len += len + 1;
2770 		}
2771 
2772 		pos += dist_to_next;
2773 	}
2774 
2775 	return (0);
2776 }
2777 
2778 /*
2779  * List extended attributes
2780  *
2781  * The FUSE_LISTXATTR operation is based on Linux's listxattr(2) syscall, which
2782  * has a number of differences compared to its FreeBSD equivalent,
2783  * extattr_list_file:
2784  *
2785  * - FUSE_LISTXATTR returns all extended attributes across all namespaces,
2786  *   whereas listxattr(2) only returns attributes for a single namespace
2787  * - FUSE_LISTXATTR prepends each attribute name with "namespace."
2788  * - If the provided buffer is not large enough to hold the result,
2789  *   FUSE_LISTXATTR should return ERANGE, whereas listxattr is expected to
2790  *   return as many results as will fit.
2791  */
2792 /*
2793     struct vop_listextattr_args {
2794 	struct vop_generic_args a_gen;
2795 	struct vnode *a_vp;
2796 	int a_attrnamespace;
2797 	struct uio *a_uio;
2798 	size_t *a_size;
2799 	struct ucred *a_cred;
2800 	struct thread *a_td;
2801     };
2802 */
2803 static int
2804 fuse_vnop_listextattr(struct vop_listextattr_args *ap)
2805 {
2806 	struct vnode *vp = ap->a_vp;
2807 	struct uio *uio = ap->a_uio;
2808 	struct fuse_dispatcher fdi;
2809 	struct fuse_listxattr_in *list_xattr_in;
2810 	struct fuse_listxattr_out *list_xattr_out;
2811 	struct mount *mp = vnode_mount(vp);
2812 	struct thread *td = ap->a_td;
2813 	struct ucred *cred = ap->a_cred;
2814 	char *prefix;
2815 	char *bsd_list = NULL;
2816 	char *linux_list;
2817 	int bsd_list_len;
2818 	int linux_list_len;
2819 	int err;
2820 
2821 	if (fuse_isdeadfs(vp))
2822 		return (ENXIO);
2823 
2824 	if (fsess_not_impl(mp, FUSE_LISTXATTR))
2825 		return EOPNOTSUPP;
2826 
2827 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2828 	if (err)
2829 		return err;
2830 
2831 	/*
2832 	 * Add space for a NUL and the period separator if enabled.
2833 	 * Default to looking for user attributes.
2834 	 */
2835 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2836 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2837 	else
2838 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2839 
2840 	fdisp_init(&fdi, sizeof(*list_xattr_in));
2841 	fdisp_make_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2842 
2843 	/*
2844 	 * Retrieve Linux / FUSE compatible list size.
2845 	 */
2846 	list_xattr_in = fdi.indata;
2847 	list_xattr_in->size = 0;
2848 
2849 	err = fdisp_wait_answ(&fdi);
2850 	if (err != 0) {
2851 		if (err == ENOSYS) {
2852 			fsess_set_notimpl(mp, FUSE_LISTXATTR);
2853 			err = EOPNOTSUPP;
2854 		}
2855 		goto out;
2856 	}
2857 
2858 	list_xattr_out = fdi.answ;
2859 	linux_list_len = list_xattr_out->size;
2860 	if (linux_list_len == 0) {
2861 		if (ap->a_size != NULL)
2862 			*ap->a_size = linux_list_len;
2863 		goto out;
2864 	}
2865 
2866 	/*
2867 	 * Retrieve Linux / FUSE compatible list values.
2868 	 */
2869 	fdisp_refresh_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2870 	list_xattr_in = fdi.indata;
2871 	list_xattr_in->size = linux_list_len;
2872 
2873 	err = fdisp_wait_answ(&fdi);
2874 	if (err == ERANGE) {
2875 		/*
2876 		 * Race detected.  The attribute list must've grown since the
2877 		 * first FUSE_LISTXATTR call.  Start over.  Go all the way back
2878 		 * to userland so we can process signals, if necessary, before
2879 		 * restarting.
2880 		 */
2881 		err = ERESTART;
2882 		goto out;
2883 	} else if (err != 0)
2884 		goto out;
2885 
2886 	linux_list = fdi.answ;
2887 	/* FUSE doesn't allow the server to return more data than requested */
2888 	if (fdi.iosize > linux_list_len) {
2889 		struct fuse_data *data = fuse_get_mpdata(mp);
2890 
2891 		fuse_warn(data, FSESS_WARN_LSEXTATTR_LONG,
2892 			"server returned "
2893 			"more extended attribute data than requested; "
2894 			"should've returned ERANGE instead.");
2895 	} else {
2896 		/* But returning less data is fine */
2897 		linux_list_len = fdi.iosize;
2898 	}
2899 
2900 	/*
2901 	 * Retrieve the BSD compatible list values.
2902 	 * The Linux / FUSE attribute list format isn't the same
2903 	 * as FreeBSD's format. So we need to transform it into
2904 	 * FreeBSD's format before giving it to the user.
2905 	 */
2906 	bsd_list = malloc(linux_list_len, M_TEMP, M_WAITOK);
2907 	err = fuse_xattrlist_convert(prefix, linux_list, linux_list_len,
2908 	    bsd_list, &bsd_list_len);
2909 	if (err != 0)
2910 		goto out;
2911 
2912 	if (ap->a_size != NULL)
2913 		*ap->a_size = bsd_list_len;
2914 
2915 	if (uio != NULL)
2916 		err = uiomove(bsd_list, bsd_list_len, uio);
2917 
2918 out:
2919 	free(bsd_list, M_TEMP);
2920 	fdisp_destroy(&fdi);
2921 	return (err);
2922 }
2923 
2924 /*
2925     struct vop_deallocate_args {
2926 	struct vop_generic_args a_gen;
2927 	struct vnode *a_vp;
2928 	off_t *a_offset;
2929 	off_t *a_len;
2930 	int a_flags;
2931 	int a_ioflag;
2932         struct ucred *a_cred;
2933     };
2934 */
2935 static int
2936 fuse_vnop_deallocate(struct vop_deallocate_args *ap)
2937 {
2938 	struct vnode *vp = ap->a_vp;
2939 	struct mount *mp = vnode_mount(vp);
2940 	struct fuse_filehandle *fufh;
2941 	struct fuse_dispatcher fdi;
2942 	struct fuse_fallocate_in *ffi;
2943 	struct ucred *cred = ap->a_cred;
2944 	pid_t pid = curthread->td_proc->p_pid;
2945 	off_t *len = ap->a_len;
2946 	off_t *offset = ap->a_offset;
2947 	int ioflag = ap->a_ioflag;
2948 	off_t filesize;
2949 	int err;
2950 	bool closefufh = false;
2951 
2952 	if (fuse_isdeadfs(vp))
2953 		return (ENXIO);
2954 
2955 	if (vfs_isrdonly(mp))
2956 		return (EROFS);
2957 
2958 	if (fsess_not_impl(mp, FUSE_FALLOCATE))
2959 		goto fallback;
2960 
2961 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2962 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2963 		/*
2964 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2965 		 * must implicitly open the file here
2966 		 */
2967 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2968 		closefufh = true;
2969 	}
2970 	if (err)
2971 		return (err);
2972 
2973 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2974 
2975 	err = fuse_vnode_size(vp, &filesize, cred, curthread);
2976 	if (err)
2977 		goto out;
2978 	fuse_inval_buf_range(vp, filesize, *offset, *offset + *len);
2979 
2980 	fdisp_init(&fdi, sizeof(*ffi));
2981 	fdisp_make_vp(&fdi, FUSE_FALLOCATE, vp, curthread, cred);
2982 	ffi = fdi.indata;
2983 	ffi->fh = fufh->fh_id;
2984 	ffi->offset = *offset;
2985 	ffi->length = *len;
2986 	/*
2987 	 * FreeBSD's fspacectl is equivalent to Linux's fallocate with
2988 	 * mode == FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE
2989 	 */
2990 	ffi->mode = FUSE_FALLOC_FL_PUNCH_HOLE | FUSE_FALLOC_FL_KEEP_SIZE;
2991 	err = fdisp_wait_answ(&fdi);
2992 
2993 	if (err == ENOSYS) {
2994 		fsess_set_notimpl(mp, FUSE_FALLOCATE);
2995 		goto fallback;
2996 	} else if (err == EOPNOTSUPP) {
2997 		/*
2998 		 * The file system server does not support FUSE_FALLOCATE with
2999 		 * the supplied mode for this particular file.
3000 		 */
3001 		goto fallback;
3002 	} else if (!err) {
3003 		/*
3004 		 * Clip the returned offset to EoF.  Do it here rather than
3005 		 * before FUSE_FALLOCATE just in case the kernel's cached file
3006 		 * size is out of date.  Unfortunately, FUSE does not return
3007 		 * any information about filesize from that operation.
3008 		 */
3009 		*offset = MIN(*offset + *len, filesize);
3010 		*len = 0;
3011 		fuse_vnode_undirty_cached_timestamps(vp, false);
3012 		fuse_internal_clear_suid_on_write(vp, cred, curthread);
3013 
3014 		if (ioflag & IO_SYNC)
3015 			err = fuse_internal_fsync(vp, curthread, MNT_WAIT,
3016 			    false);
3017 	}
3018 
3019 out:
3020 	if (closefufh)
3021 		fuse_filehandle_close(vp, fufh, curthread, cred);
3022 
3023 	return (err);
3024 
3025 fallback:
3026 	if (closefufh)
3027 		fuse_filehandle_close(vp, fufh, curthread, cred);
3028 
3029 	return (vop_stddeallocate(ap));
3030 }
3031 
3032 /*
3033     struct vop_deleteextattr_args {
3034 	struct vop_generic_args a_gen;
3035 	struct vnode *a_vp;
3036 	int a_attrnamespace;
3037 	const char *a_name;
3038 	struct ucred *a_cred;
3039 	struct thread *a_td;
3040     };
3041 */
3042 static int
3043 fuse_vnop_deleteextattr(struct vop_deleteextattr_args *ap)
3044 {
3045 	struct vnode *vp = ap->a_vp;
3046 	struct fuse_dispatcher fdi;
3047 	struct mount *mp = vnode_mount(vp);
3048 	struct thread *td = ap->a_td;
3049 	struct ucred *cred = ap->a_cred;
3050 	char *prefix;
3051 	size_t len;
3052 	char *attr_str;
3053 	int err;
3054 
3055 	if (fuse_isdeadfs(vp))
3056 		return (ENXIO);
3057 
3058 	if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
3059 		return EOPNOTSUPP;
3060 
3061 	if (vfs_isrdonly(mp))
3062 		return EROFS;
3063 
3064 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
3065 		VWRITE);
3066 	if (err)
3067 		return err;
3068 
3069 	/* Default to looking for user attributes. */
3070 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
3071 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
3072 	else
3073 		prefix = EXTATTR_NAMESPACE_USER_STRING;
3074 
3075 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
3076 	    strlen(ap->a_name) + 1;
3077 
3078 	fdisp_init(&fdi, len);
3079 	fdisp_make_vp(&fdi, FUSE_REMOVEXATTR, vp, td, cred);
3080 
3081 	attr_str = fdi.indata;
3082 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
3083 	    ap->a_name);
3084 
3085 	err = fdisp_wait_answ(&fdi);
3086 	if (err == ENOSYS) {
3087 		fsess_set_notimpl(mp, FUSE_REMOVEXATTR);
3088 		err = EOPNOTSUPP;
3089 	}
3090 
3091 	fdisp_destroy(&fdi);
3092 	return (err);
3093 }
3094 
3095 /*
3096     struct vnop_print_args {
3097 	struct vnode *a_vp;
3098     };
3099 */
3100 static int
3101 fuse_vnop_print(struct vop_print_args *ap)
3102 {
3103 	struct fuse_vnode_data *fvdat = VTOFUD(ap->a_vp);
3104 
3105 	printf("nodeid: %ju, parent nodeid: %ju, nlookup: %ju, flag: %#x\n",
3106 	    (uintmax_t)VTOILLU(ap->a_vp), (uintmax_t)fvdat->parent_nid,
3107 	    (uintmax_t)fvdat->nlookup,
3108 	    fvdat->flag);
3109 
3110 	return 0;
3111 }
3112 
3113 /*
3114  * Get an NFS filehandle for a FUSE file.
3115  *
3116  * This will only work for FUSE file systems that guarantee the uniqueness of
3117  * nodeid:generation, which most don't.
3118  */
3119 /*
3120 vop_vptofh {
3121 	IN struct vnode *a_vp;
3122 	IN struct fid *a_fhp;
3123 };
3124 */
3125 static int
3126 fuse_vnop_vptofh(struct vop_vptofh_args *ap)
3127 {
3128 	struct vnode *vp = ap->a_vp;
3129 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
3130 	struct fuse_fid *fhp = (struct fuse_fid *)(ap->a_fhp);
3131 	_Static_assert(sizeof(struct fuse_fid) <= sizeof(struct fid),
3132 		"FUSE fid type is too big");
3133 	struct mount *mp = vnode_mount(vp);
3134 	struct fuse_data *data = fuse_get_mpdata(mp);
3135 	struct vattr va;
3136 	int err;
3137 
3138 	if (!(data->dataflags & FSESS_EXPORT_SUPPORT)) {
3139 		/* NFS requires lookups for "." and ".." */
3140 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3141 			"VOP_VPTOFH without FUSE_EXPORT_SUPPORT");
3142 		return EOPNOTSUPP;
3143 	}
3144 	if ((mp->mnt_flag & MNT_EXPORTED) &&
3145 		!(data->dataflags & FSESS_NO_OPENDIR_SUPPORT))
3146 	{
3147 		/*
3148 		 * NFS is stateless, so nfsd must reopen a directory on every
3149 		 * call to VOP_READDIR, passing in the d_off field from the
3150 		 * final dirent of the previous invocation.  But without
3151 		 * FUSE_NO_OPENDIR_SUPPORT, the FUSE protocol does not
3152 		 * guarantee that d_off will be valid after a directory is
3153 		 * closed and reopened.  So prohibit exporting FUSE file
3154 		 * systems that don't set that flag.
3155 		 *
3156 		 * But userspace NFS servers don't have this problem.
3157                  */
3158 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3159 			"VOP_VPTOFH without FUSE_NO_OPENDIR_SUPPORT");
3160 		return EOPNOTSUPP;
3161 	}
3162 
3163 	err = fuse_internal_getattr(vp, &va, curthread->td_ucred, curthread);
3164 	if (err)
3165 		return err;
3166 
3167 	/*ip = VTOI(ap->a_vp);*/
3168 	/*ufhp = (struct ufid *)ap->a_fhp;*/
3169 	fhp->len = sizeof(struct fuse_fid);
3170 	fhp->nid = fvdat->nid;
3171 	if (fvdat->generation <= UINT32_MAX)
3172 		fhp->gen = fvdat->generation;
3173 	else
3174 		return EOVERFLOW;
3175 	return (0);
3176 }
3177