xref: /freebsd/sys/fs/fuse/fuse_vnops.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 #include <sys/param.h>
65 #include <sys/module.h>
66 #include <sys/systm.h>
67 #include <sys/errno.h>
68 #include <sys/kernel.h>
69 #include <sys/conf.h>
70 #include <sys/filio.h>
71 #include <sys/uio.h>
72 #include <sys/malloc.h>
73 #include <sys/queue.h>
74 #include <sys/limits.h>
75 #include <sys/lock.h>
76 #include <sys/rwlock.h>
77 #include <sys/sx.h>
78 #include <sys/proc.h>
79 #include <sys/mount.h>
80 #include <sys/vnode.h>
81 #include <sys/namei.h>
82 #include <sys/extattr.h>
83 #include <sys/stat.h>
84 #include <sys/unistd.h>
85 #include <sys/filedesc.h>
86 #include <sys/file.h>
87 #include <sys/fcntl.h>
88 #include <sys/dirent.h>
89 #include <sys/bio.h>
90 #include <sys/buf.h>
91 #include <sys/sysctl.h>
92 #include <sys/vmmeter.h>
93 
94 #include <vm/vm.h>
95 #include <vm/vm_extern.h>
96 #include <vm/pmap.h>
97 #include <vm/vm_map.h>
98 #include <vm/vm_page.h>
99 #include <vm/vm_param.h>
100 #include <vm/vm_object.h>
101 #include <vm/vm_pager.h>
102 #include <vm/vnode_pager.h>
103 #include <vm/vm_object.h>
104 
105 #include "fuse.h"
106 #include "fuse_file.h"
107 #include "fuse_internal.h"
108 #include "fuse_ipc.h"
109 #include "fuse_node.h"
110 #include "fuse_io.h"
111 
112 #include <sys/priv.h>
113 
114 /* Maximum number of hardlinks to a single FUSE file */
115 #define FUSE_LINK_MAX                      UINT32_MAX
116 
117 SDT_PROVIDER_DECLARE(fusefs);
118 /*
119  * Fuse trace probe:
120  * arg0: verbosity.  Higher numbers give more verbose messages
121  * arg1: Textual message
122  */
123 SDT_PROBE_DEFINE2(fusefs, , vnops, trace, "int", "char*");
124 
125 /* vnode ops */
126 static vop_access_t fuse_vnop_access;
127 static vop_advlock_t fuse_vnop_advlock;
128 static vop_allocate_t fuse_vnop_allocate;
129 static vop_bmap_t fuse_vnop_bmap;
130 static vop_close_t fuse_fifo_close;
131 static vop_close_t fuse_vnop_close;
132 static vop_copy_file_range_t fuse_vnop_copy_file_range;
133 static vop_create_t fuse_vnop_create;
134 static vop_deallocate_t fuse_vnop_deallocate;
135 static vop_deleteextattr_t fuse_vnop_deleteextattr;
136 static vop_fdatasync_t fuse_vnop_fdatasync;
137 static vop_fsync_t fuse_vnop_fsync;
138 static vop_getattr_t fuse_vnop_getattr;
139 static vop_getextattr_t fuse_vnop_getextattr;
140 static vop_inactive_t fuse_vnop_inactive;
141 static vop_ioctl_t fuse_vnop_ioctl;
142 static vop_link_t fuse_vnop_link;
143 static vop_listextattr_t fuse_vnop_listextattr;
144 static vop_lookup_t fuse_vnop_lookup;
145 static vop_mkdir_t fuse_vnop_mkdir;
146 static vop_mknod_t fuse_vnop_mknod;
147 static vop_open_t fuse_vnop_open;
148 static vop_pathconf_t fuse_vnop_pathconf;
149 static vop_read_t fuse_vnop_read;
150 static vop_readdir_t fuse_vnop_readdir;
151 static vop_readlink_t fuse_vnop_readlink;
152 static vop_reclaim_t fuse_vnop_reclaim;
153 static vop_remove_t fuse_vnop_remove;
154 static vop_rename_t fuse_vnop_rename;
155 static vop_rmdir_t fuse_vnop_rmdir;
156 static vop_setattr_t fuse_vnop_setattr;
157 static vop_setextattr_t fuse_vnop_setextattr;
158 static vop_strategy_t fuse_vnop_strategy;
159 static vop_symlink_t fuse_vnop_symlink;
160 static vop_write_t fuse_vnop_write;
161 static vop_getpages_t fuse_vnop_getpages;
162 static vop_print_t fuse_vnop_print;
163 static vop_vptofh_t fuse_vnop_vptofh;
164 
165 struct vop_vector fuse_fifoops = {
166 	.vop_default =		&fifo_specops,
167 	.vop_access =		fuse_vnop_access,
168 	.vop_close =		fuse_fifo_close,
169 	.vop_fsync =		fuse_vnop_fsync,
170 	.vop_getattr =		fuse_vnop_getattr,
171 	.vop_inactive =		fuse_vnop_inactive,
172 	.vop_pathconf =		fuse_vnop_pathconf,
173 	.vop_print =		fuse_vnop_print,
174 	.vop_read =		VOP_PANIC,
175 	.vop_reclaim =		fuse_vnop_reclaim,
176 	.vop_setattr =		fuse_vnop_setattr,
177 	.vop_write =		VOP_PANIC,
178 	.vop_vptofh =		fuse_vnop_vptofh,
179 };
180 VFS_VOP_VECTOR_REGISTER(fuse_fifoops);
181 
182 struct vop_vector fuse_vnops = {
183 	.vop_allocate =	fuse_vnop_allocate,
184 	.vop_default = &default_vnodeops,
185 	.vop_access = fuse_vnop_access,
186 	.vop_advlock = fuse_vnop_advlock,
187 	.vop_bmap = fuse_vnop_bmap,
188 	.vop_close = fuse_vnop_close,
189 	.vop_copy_file_range = fuse_vnop_copy_file_range,
190 	.vop_create = fuse_vnop_create,
191 	.vop_deallocate = fuse_vnop_deallocate,
192 	.vop_deleteextattr = fuse_vnop_deleteextattr,
193 	.vop_fsync = fuse_vnop_fsync,
194 	.vop_fdatasync = fuse_vnop_fdatasync,
195 	.vop_getattr = fuse_vnop_getattr,
196 	.vop_getextattr = fuse_vnop_getextattr,
197 	.vop_inactive = fuse_vnop_inactive,
198 	.vop_ioctl = fuse_vnop_ioctl,
199 	.vop_link = fuse_vnop_link,
200 	.vop_listextattr = fuse_vnop_listextattr,
201 	.vop_lookup = fuse_vnop_lookup,
202 	.vop_mkdir = fuse_vnop_mkdir,
203 	.vop_mknod = fuse_vnop_mknod,
204 	.vop_open = fuse_vnop_open,
205 	.vop_pathconf = fuse_vnop_pathconf,
206 	/*
207 	 * TODO: implement vop_poll after upgrading to protocol 7.21.
208 	 * FUSE_POLL was added in protocol 7.11, but it's kind of broken until
209 	 * 7.21, which adds the ability for the client to choose which poll
210 	 * events it wants, and for a client to deregister a file handle
211 	 */
212 	.vop_read = fuse_vnop_read,
213 	.vop_readdir = fuse_vnop_readdir,
214 	.vop_readlink = fuse_vnop_readlink,
215 	.vop_reclaim = fuse_vnop_reclaim,
216 	.vop_remove = fuse_vnop_remove,
217 	.vop_rename = fuse_vnop_rename,
218 	.vop_rmdir = fuse_vnop_rmdir,
219 	.vop_setattr = fuse_vnop_setattr,
220 	.vop_setextattr = fuse_vnop_setextattr,
221 	.vop_strategy = fuse_vnop_strategy,
222 	.vop_symlink = fuse_vnop_symlink,
223 	.vop_write = fuse_vnop_write,
224 	.vop_getpages = fuse_vnop_getpages,
225 	.vop_print = fuse_vnop_print,
226 	.vop_vptofh = fuse_vnop_vptofh,
227 };
228 VFS_VOP_VECTOR_REGISTER(fuse_vnops);
229 
230 /* Check permission for extattr operations, much like extattr_check_cred */
231 static int
232 fuse_extattr_check_cred(struct vnode *vp, int ns, struct ucred *cred,
233 	struct thread *td, accmode_t accmode)
234 {
235 	struct mount *mp = vnode_mount(vp);
236 	struct fuse_data *data = fuse_get_mpdata(mp);
237 	int default_permissions = data->dataflags & FSESS_DEFAULT_PERMISSIONS;
238 
239 	/*
240 	 * Kernel-invoked always succeeds.
241 	 */
242 	if (cred == NOCRED)
243 		return (0);
244 
245 	/*
246 	 * Do not allow privileged processes in jail to directly manipulate
247 	 * system attributes.
248 	 */
249 	switch (ns) {
250 	case EXTATTR_NAMESPACE_SYSTEM:
251 		if (default_permissions) {
252 			return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM));
253 		}
254 		return (0);
255 	case EXTATTR_NAMESPACE_USER:
256 		if (default_permissions) {
257 			return (fuse_internal_access(vp, accmode, td, cred));
258 		}
259 		return (0);
260 	default:
261 		return (EPERM);
262 	}
263 }
264 
265 /* Get a filehandle for a directory */
266 static int
267 fuse_filehandle_get_dir(struct vnode *vp, struct fuse_filehandle **fufhp,
268 	struct ucred *cred, pid_t pid)
269 {
270 	if (fuse_filehandle_get(vp, FREAD, fufhp, cred, pid) == 0)
271 		return 0;
272 	return fuse_filehandle_get(vp, FEXEC, fufhp, cred, pid);
273 }
274 
275 /* Send FUSE_FLUSH for this vnode */
276 static int
277 fuse_flush(struct vnode *vp, struct ucred *cred, pid_t pid, int fflag)
278 {
279 	struct fuse_flush_in *ffi;
280 	struct fuse_filehandle *fufh;
281 	struct fuse_dispatcher fdi;
282 	struct thread *td = curthread;
283 	struct mount *mp = vnode_mount(vp);
284 	int err;
285 
286 	if (fsess_not_impl(vnode_mount(vp), FUSE_FLUSH))
287 		return 0;
288 
289 	err = fuse_filehandle_getrw(vp, fflag, &fufh, cred, pid);
290 	if (err)
291 		return err;
292 
293 	fdisp_init(&fdi, sizeof(*ffi));
294 	fdisp_make_vp(&fdi, FUSE_FLUSH, vp, td, cred);
295 	ffi = fdi.indata;
296 	ffi->fh = fufh->fh_id;
297 	/*
298 	 * If the file has a POSIX lock then we're supposed to set lock_owner.
299 	 * If not, then lock_owner is undefined.  So we may as well always set
300 	 * it.
301 	 */
302 	ffi->lock_owner = td->td_proc->p_pid;
303 
304 	err = fdisp_wait_answ(&fdi);
305 	if (err == ENOSYS) {
306 		fsess_set_notimpl(mp, FUSE_FLUSH);
307 		err = 0;
308 	}
309 	fdisp_destroy(&fdi);
310 	return err;
311 }
312 
313 /* Close wrapper for fifos.  */
314 static int
315 fuse_fifo_close(struct vop_close_args *ap)
316 {
317 	return (fifo_specops.vop_close(ap));
318 }
319 
320 /* Invalidate a range of cached data, whether dirty of not */
321 static int
322 fuse_inval_buf_range(struct vnode *vp, off_t filesize, off_t start, off_t end)
323 {
324 	struct buf *bp;
325 	daddr_t left_lbn, end_lbn, right_lbn;
326 	off_t new_filesize;
327 	int iosize, left_on, right_on, right_blksize;
328 
329 	iosize = fuse_iosize(vp);
330 	left_lbn = start / iosize;
331 	end_lbn = howmany(end, iosize);
332 	left_on = start & (iosize - 1);
333 	if (left_on != 0) {
334 		bp = getblk(vp, left_lbn, iosize, PCATCH, 0, 0);
335 		if ((bp->b_flags & B_CACHE) != 0 && bp->b_dirtyend >= left_on) {
336 			/*
337 			 * Flush the dirty buffer, because we don't have a
338 			 * byte-granular way to record which parts of the
339 			 * buffer are valid.
340 			 */
341 			bwrite(bp);
342 			if (bp->b_error)
343 				return (bp->b_error);
344 		} else {
345 			brelse(bp);
346 		}
347 	}
348 	right_on = end & (iosize - 1);
349 	if (right_on != 0) {
350 		right_lbn = end / iosize;
351 		new_filesize = MAX(filesize, end);
352 		right_blksize = MIN(iosize, new_filesize - iosize * right_lbn);
353 		bp = getblk(vp, right_lbn, right_blksize, PCATCH, 0, 0);
354 		if ((bp->b_flags & B_CACHE) != 0 && bp->b_dirtyoff < right_on) {
355 			/*
356 			 * Flush the dirty buffer, because we don't have a
357 			 * byte-granular way to record which parts of the
358 			 * buffer are valid.
359 			 */
360 			bwrite(bp);
361 			if (bp->b_error)
362 				return (bp->b_error);
363 		} else {
364 			brelse(bp);
365 		}
366 	}
367 
368 	v_inval_buf_range(vp, left_lbn, end_lbn, iosize);
369 	return (0);
370 }
371 
372 
373 /* Send FUSE_LSEEK for this node */
374 static int
375 fuse_vnop_do_lseek(struct vnode *vp, struct thread *td, struct ucred *cred,
376 	pid_t pid, off_t *offp, int whence)
377 {
378 	struct fuse_dispatcher fdi;
379 	struct fuse_filehandle *fufh;
380 	struct fuse_lseek_in *flsi;
381 	struct fuse_lseek_out *flso;
382 	struct mount *mp = vnode_mount(vp);
383 	int err;
384 
385 	ASSERT_VOP_LOCKED(vp, __func__);
386 
387 	err = fuse_filehandle_getrw(vp, FREAD, &fufh, cred, pid);
388 	if (err)
389 		return (err);
390 	fdisp_init(&fdi, sizeof(*flsi));
391 	fdisp_make_vp(&fdi, FUSE_LSEEK, vp, td, cred);
392 	flsi = fdi.indata;
393 	flsi->fh = fufh->fh_id;
394 	flsi->offset = *offp;
395 	flsi->whence = whence;
396 	err = fdisp_wait_answ(&fdi);
397 	if (err == ENOSYS) {
398 		fsess_set_notimpl(mp, FUSE_LSEEK);
399 	} else if (err == 0) {
400 		fsess_set_impl(mp, FUSE_LSEEK);
401 		flso = fdi.answ;
402 		*offp = flso->offset;
403 	}
404 	fdisp_destroy(&fdi);
405 
406 	return (err);
407 }
408 
409 /*
410     struct vnop_access_args {
411 	struct vnode *a_vp;
412 #if VOP_ACCESS_TAKES_ACCMODE_T
413 	accmode_t a_accmode;
414 #else
415 	int a_mode;
416 #endif
417 	struct ucred *a_cred;
418 	struct thread *a_td;
419     };
420 */
421 static int
422 fuse_vnop_access(struct vop_access_args *ap)
423 {
424 	struct vnode *vp = ap->a_vp;
425 	int accmode = ap->a_accmode;
426 	struct ucred *cred = ap->a_cred;
427 
428 	struct fuse_data *data = fuse_get_mpdata(vnode_mount(vp));
429 
430 	int err;
431 
432 	if (fuse_isdeadfs(vp)) {
433 		if (vnode_isvroot(vp)) {
434 			return 0;
435 		}
436 		return ENXIO;
437 	}
438 	if (!(data->dataflags & FSESS_INITED)) {
439 		if (vnode_isvroot(vp)) {
440 			if (priv_check_cred(cred, PRIV_VFS_ADMIN) ||
441 			    (fuse_match_cred(data->daemoncred, cred) == 0)) {
442 				return 0;
443 			}
444 		}
445 		return EBADF;
446 	}
447 	if (vnode_islnk(vp)) {
448 		return 0;
449 	}
450 
451 	err = fuse_internal_access(vp, accmode, ap->a_td, ap->a_cred);
452 	return err;
453 }
454 
455 /*
456  * struct vop_advlock_args {
457  *	struct vop_generic_args a_gen;
458  *	struct vnode *a_vp;
459  *	void *a_id;
460  *	int a_op;
461  *	struct flock *a_fl;
462  *	int a_flags;
463  * }
464  */
465 static int
466 fuse_vnop_advlock(struct vop_advlock_args *ap)
467 {
468 	struct vnode *vp = ap->a_vp;
469 	struct flock *fl = ap->a_fl;
470 	struct thread *td = curthread;
471 	struct ucred *cred = td->td_ucred;
472 	pid_t pid = td->td_proc->p_pid;
473 	struct fuse_filehandle *fufh;
474 	struct fuse_dispatcher fdi;
475 	struct fuse_lk_in *fli;
476 	struct fuse_lk_out *flo;
477 	struct vattr vattr;
478 	enum fuse_opcode op;
479 	off_t size, start;
480 	int dataflags, err;
481 	int flags = ap->a_flags;
482 
483 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
484 
485 	if (fuse_isdeadfs(vp)) {
486 		return ENXIO;
487 	}
488 
489 	switch(ap->a_op) {
490 	case F_GETLK:
491 		op = FUSE_GETLK;
492 		break;
493 	case F_SETLK:
494 		if (flags & F_WAIT)
495 			op = FUSE_SETLKW;
496 		else
497 			op = FUSE_SETLK;
498 		break;
499 	case F_UNLCK:
500 		op = FUSE_SETLK;
501 		break;
502 	default:
503 		return EINVAL;
504 	}
505 
506 	if (!(dataflags & FSESS_POSIX_LOCKS))
507 		return vop_stdadvlock(ap);
508 	/* FUSE doesn't properly support flock until protocol 7.17 */
509 	if (flags & F_FLOCK)
510 		return vop_stdadvlock(ap);
511 
512 	vn_lock(vp, LK_SHARED | LK_RETRY);
513 
514 	switch (fl->l_whence) {
515 	case SEEK_SET:
516 	case SEEK_CUR:
517 		/*
518 		 * Caller is responsible for adding any necessary offset
519 		 * when SEEK_CUR is used.
520 		 */
521 		start = fl->l_start;
522 		break;
523 
524 	case SEEK_END:
525 		err = fuse_internal_getattr(vp, &vattr, cred, td);
526 		if (err)
527 			goto out;
528 		size = vattr.va_size;
529 		if (size > OFF_MAX ||
530 		    (fl->l_start > 0 && size > OFF_MAX - fl->l_start)) {
531 			err = EOVERFLOW;
532 			goto out;
533 		}
534 		start = size + fl->l_start;
535 		break;
536 
537 	default:
538 		return (EINVAL);
539 	}
540 
541 	err = fuse_filehandle_get_anyflags(vp, &fufh, cred, pid);
542 	if (err)
543 		goto out;
544 
545 	fdisp_init(&fdi, sizeof(*fli));
546 
547 	fdisp_make_vp(&fdi, op, vp, td, cred);
548 	fli = fdi.indata;
549 	fli->fh = fufh->fh_id;
550 	fli->owner = td->td_proc->p_pid;
551 	fli->lk.start = start;
552 	if (fl->l_len != 0)
553 		fli->lk.end = start + fl->l_len - 1;
554 	else
555 		fli->lk.end = INT64_MAX;
556 	fli->lk.type = fl->l_type;
557 	fli->lk.pid = td->td_proc->p_pid;
558 
559 	err = fdisp_wait_answ(&fdi);
560 	fdisp_destroy(&fdi);
561 
562 	if (err == 0 && op == FUSE_GETLK) {
563 		flo = fdi.answ;
564 		fl->l_type = flo->lk.type;
565 		fl->l_whence = SEEK_SET;
566 		if (flo->lk.type != F_UNLCK) {
567 			fl->l_pid = flo->lk.pid;
568 			fl->l_start = flo->lk.start;
569 			if (flo->lk.end == INT64_MAX)
570 				fl->l_len = 0;
571 			else
572 				fl->l_len = flo->lk.end - flo->lk.start + 1;
573 			fl->l_start = flo->lk.start;
574 		}
575 	}
576 
577 out:
578 	VOP_UNLOCK(vp);
579 	return err;
580 }
581 
582 static int
583 fuse_vnop_allocate(struct vop_allocate_args *ap)
584 {
585 	struct vnode *vp = ap->a_vp;
586 	off_t *len = ap->a_len;
587 	off_t *offset = ap->a_offset;
588 	struct ucred *cred = ap->a_cred;
589 	struct fuse_filehandle *fufh;
590 	struct mount *mp = vnode_mount(vp);
591 	struct fuse_dispatcher fdi;
592 	struct fuse_fallocate_in *ffi;
593 	struct uio io;
594 	pid_t pid = curthread->td_proc->p_pid;
595 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
596 	off_t filesize;
597 	int err;
598 
599 	if (fuse_isdeadfs(vp))
600 		return (ENXIO);
601 
602 	switch (vp->v_type) {
603 	case VFIFO:
604 		return (ESPIPE);
605 	case VLNK:
606 	case VREG:
607 		if (vfs_isrdonly(mp))
608 			return (EROFS);
609 		break;
610 	default:
611 		return (ENODEV);
612 	}
613 
614 	if (vfs_isrdonly(mp))
615 		return (EROFS);
616 
617 	if (fsess_not_impl(mp, FUSE_FALLOCATE))
618 		return (EINVAL);
619 
620 	io.uio_offset = *offset;
621 	io.uio_resid = *len;
622 	err = vn_rlimit_fsize(vp, &io, curthread);
623 	if (err)
624 		return (err);
625 
626 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
627 	if (err)
628 		return (err);
629 
630 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
631 
632 	err = fuse_vnode_size(vp, &filesize, cred, curthread);
633 	if (err)
634 		return (err);
635 	fuse_inval_buf_range(vp, filesize, *offset, *offset + *len);
636 
637 	fdisp_init(&fdi, sizeof(*ffi));
638 	fdisp_make_vp(&fdi, FUSE_FALLOCATE, vp, curthread, cred);
639 	ffi = fdi.indata;
640 	ffi->fh = fufh->fh_id;
641 	ffi->offset = *offset;
642 	ffi->length = *len;
643 	ffi->mode = 0;
644 	err = fdisp_wait_answ(&fdi);
645 
646 	if (err == ENOSYS) {
647 		fsess_set_notimpl(mp, FUSE_FALLOCATE);
648 		err = EINVAL;
649 	} else if (err == EOPNOTSUPP) {
650 		/*
651 		 * The file system server does not support FUSE_FALLOCATE with
652 		 * the supplied mode for this particular file.
653 		 */
654 		err = EINVAL;
655 	} else if (!err) {
656 		*offset += *len;
657 		*len = 0;
658 		fuse_vnode_undirty_cached_timestamps(vp, false);
659 		fuse_internal_clear_suid_on_write(vp, cred, curthread);
660 		if (*offset > fvdat->cached_attrs.va_size) {
661 			fuse_vnode_setsize(vp, *offset, false);
662 			getnanouptime(&fvdat->last_local_modify);
663 		}
664 	}
665 
666 	fdisp_destroy(&fdi);
667 	return (err);
668 }
669 
670 /* {
671 	struct vnode *a_vp;
672 	daddr_t a_bn;
673 	struct bufobj **a_bop;
674 	daddr_t *a_bnp;
675 	int *a_runp;
676 	int *a_runb;
677 } */
678 static int
679 fuse_vnop_bmap(struct vop_bmap_args *ap)
680 {
681 	struct vnode *vp = ap->a_vp;
682 	struct bufobj **bo = ap->a_bop;
683 	struct thread *td = curthread;
684 	struct mount *mp;
685 	struct fuse_dispatcher fdi;
686 	struct fuse_bmap_in *fbi;
687 	struct fuse_bmap_out *fbo;
688 	struct fuse_data *data;
689 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
690 	uint64_t biosize;
691 	off_t fsize;
692 	daddr_t lbn = ap->a_bn;
693 	daddr_t *pbn = ap->a_bnp;
694 	int *runp = ap->a_runp;
695 	int *runb = ap->a_runb;
696 	int error = 0;
697 	int maxrun;
698 
699 	if (fuse_isdeadfs(vp)) {
700 		return ENXIO;
701 	}
702 
703 	mp = vnode_mount(vp);
704 	data = fuse_get_mpdata(mp);
705 	biosize = fuse_iosize(vp);
706 	maxrun = MIN(vp->v_mount->mnt_iosize_max / biosize - 1,
707 		data->max_readahead_blocks);
708 
709 	if (bo != NULL)
710 		*bo = &vp->v_bufobj;
711 
712 	/*
713 	 * The FUSE_BMAP operation does not include the runp and runb
714 	 * variables, so we must guess.  Report nonzero contiguous runs so
715 	 * cluster_read will combine adjacent reads.  It's worthwhile to reduce
716 	 * upcalls even if we don't know the true physical layout of the file.
717 	 *
718 	 * FUSE file systems may opt out of read clustering in two ways:
719 	 * * mounting with -onoclusterr
720 	 * * Setting max_readahead <= maxbcachebuf during FUSE_INIT
721 	 */
722 	if (runb != NULL)
723 		*runb = MIN(lbn, maxrun);
724 	if (runp != NULL && maxrun == 0)
725 		*runp = 0;
726 	else if (runp != NULL) {
727 		/*
728 		 * If the file's size is cached, use that value to calculate
729 		 * runp, even if the cache is expired.  runp is only advisory,
730 		 * and the risk of getting it wrong is not worth the cost of
731 		 * another upcall.
732 		 */
733 		if (fvdat->cached_attrs.va_size != VNOVAL)
734 			fsize = fvdat->cached_attrs.va_size;
735 		else
736 			error = fuse_vnode_size(vp, &fsize, td->td_ucred, td);
737 		if (error == 0)
738 			*runp = MIN(MAX(0, fsize / (off_t)biosize - lbn - 1),
739 				    maxrun);
740 		else
741 			*runp = 0;
742 	}
743 
744 	if (fsess_maybe_impl(mp, FUSE_BMAP)) {
745 		fdisp_init(&fdi, sizeof(*fbi));
746 		fdisp_make_vp(&fdi, FUSE_BMAP, vp, td, td->td_ucred);
747 		fbi = fdi.indata;
748 		fbi->block = lbn;
749 		fbi->blocksize = biosize;
750 		error = fdisp_wait_answ(&fdi);
751 		if (error == ENOSYS) {
752 			fdisp_destroy(&fdi);
753 			fsess_set_notimpl(mp, FUSE_BMAP);
754 			error = 0;
755 		} else {
756 			fbo = fdi.answ;
757 			if (error == 0 && pbn != NULL)
758 				*pbn = fbo->block;
759 			fdisp_destroy(&fdi);
760 			return error;
761 		}
762 	}
763 
764 	/* If the daemon doesn't support BMAP, make up a sensible default */
765 	if (pbn != NULL)
766 		*pbn = lbn * btodb(biosize);
767 	return (error);
768 }
769 
770 /*
771     struct vop_close_args {
772 	struct vnode *a_vp;
773 	int  a_fflag;
774 	struct ucred *a_cred;
775 	struct thread *a_td;
776     };
777 */
778 static int
779 fuse_vnop_close(struct vop_close_args *ap)
780 {
781 	struct vnode *vp = ap->a_vp;
782 	struct ucred *cred = ap->a_cred;
783 	int fflag = ap->a_fflag;
784 	struct thread *td = ap->a_td;
785 	pid_t pid = td->td_proc->p_pid;
786 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
787 	int err = 0;
788 
789 	if (fuse_isdeadfs(vp))
790 		return 0;
791 	if (vnode_isdir(vp))
792 		return 0;
793 	if (fflag & IO_NDELAY)
794 		return 0;
795 
796 	err = fuse_flush(vp, cred, pid, fflag);
797 	if (err == 0 && (fvdat->flag & FN_ATIMECHANGE)) {
798 		struct vattr vap;
799 
800 		VATTR_NULL(&vap);
801 		vap.va_atime = fvdat->cached_attrs.va_atime;
802 		err = fuse_internal_setattr(vp, &vap, td, NULL);
803 	}
804 	/* TODO: close the file handle, if we're sure it's no longer used */
805 	if ((fvdat->flag & FN_SIZECHANGE) != 0) {
806 		fuse_vnode_savesize(vp, cred, td->td_proc->p_pid);
807 	}
808 	return err;
809 }
810 
811 /*
812    struct vop_copy_file_range_args {
813 	struct vop_generic_args a_gen;
814 	struct vnode *a_invp;
815 	off_t *a_inoffp;
816 	struct vnode *a_outvp;
817 	off_t *a_outoffp;
818 	size_t *a_lenp;
819 	unsigned int a_flags;
820 	struct ucred *a_incred;
821 	struct ucred *a_outcred;
822 	struct thread *a_fsizetd;
823 }
824  */
825 static int
826 fuse_vnop_copy_file_range(struct vop_copy_file_range_args *ap)
827 {
828 	struct vnode *invp = ap->a_invp;
829 	struct vnode *outvp = ap->a_outvp;
830 	struct mount *mp = vnode_mount(invp);
831 	struct fuse_vnode_data *outfvdat = VTOFUD(outvp);
832 	struct fuse_dispatcher fdi;
833 	struct fuse_filehandle *infufh, *outfufh;
834 	struct fuse_copy_file_range_in *fcfri;
835 	struct ucred *incred = ap->a_incred;
836 	struct ucred *outcred = ap->a_outcred;
837 	struct fuse_write_out *fwo;
838 	struct thread *td;
839 	struct uio io;
840 	off_t outfilesize;
841 	ssize_t r = 0;
842 	pid_t pid;
843 	int err;
844 
845 	if (mp != vnode_mount(outvp))
846 		goto fallback;
847 
848 	if (incred->cr_uid != outcred->cr_uid)
849 		goto fallback;
850 
851 	if (incred->cr_groups[0] != outcred->cr_groups[0])
852 		goto fallback;
853 
854 	if (fsess_not_impl(mp, FUSE_COPY_FILE_RANGE))
855 		goto fallback;
856 
857 	if (ap->a_fsizetd == NULL)
858 		td = curthread;
859 	else
860 		td = ap->a_fsizetd;
861 	pid = td->td_proc->p_pid;
862 
863 	/* Lock both vnodes, avoiding risk of deadlock. */
864 	do {
865 		err = vn_lock(outvp, LK_EXCLUSIVE);
866 		if (invp == outvp)
867 			break;
868 		if (err == 0) {
869 			err = vn_lock(invp, LK_SHARED | LK_NOWAIT);
870 			if (err == 0)
871 				break;
872 			VOP_UNLOCK(outvp);
873 			err = vn_lock(invp, LK_SHARED);
874 			if (err == 0)
875 				VOP_UNLOCK(invp);
876 		}
877 	} while (err == 0);
878 	if (err != 0)
879 		return (err);
880 
881 	err = fuse_filehandle_getrw(invp, FREAD, &infufh, incred, pid);
882 	if (err)
883 		goto unlock;
884 
885 	err = fuse_filehandle_getrw(outvp, FWRITE, &outfufh, outcred, pid);
886 	if (err)
887 		goto unlock;
888 
889 	io.uio_resid = *ap->a_lenp;
890 	if (ap->a_fsizetd) {
891 		io.uio_offset = *ap->a_outoffp;
892 		err = vn_rlimit_fsizex(outvp, &io, 0, &r, ap->a_fsizetd);
893 		if (err != 0)
894 			goto unlock;
895 	}
896 
897 	err = fuse_vnode_size(outvp, &outfilesize, outcred, curthread);
898 	if (err)
899 		goto unlock;
900 
901 	err = fuse_inval_buf_range(outvp, outfilesize, *ap->a_outoffp,
902 		*ap->a_outoffp + io.uio_resid);
903 	if (err)
904 		goto unlock;
905 
906 	fdisp_init(&fdi, sizeof(*fcfri));
907 	fdisp_make_vp(&fdi, FUSE_COPY_FILE_RANGE, invp, td, incred);
908 	fcfri = fdi.indata;
909 	fcfri->fh_in = infufh->fh_id;
910 	fcfri->off_in = *ap->a_inoffp;
911 	fcfri->nodeid_out = VTOI(outvp);
912 	fcfri->fh_out = outfufh->fh_id;
913 	fcfri->off_out = *ap->a_outoffp;
914 	fcfri->len = io.uio_resid;
915 	fcfri->flags = 0;
916 
917 	err = fdisp_wait_answ(&fdi);
918 	if (err == 0) {
919 		fwo = fdi.answ;
920 		*ap->a_lenp = fwo->size;
921 		*ap->a_inoffp += fwo->size;
922 		*ap->a_outoffp += fwo->size;
923 		fuse_internal_clear_suid_on_write(outvp, outcred, td);
924 		if (*ap->a_outoffp > outfvdat->cached_attrs.va_size) {
925                         fuse_vnode_setsize(outvp, *ap->a_outoffp, false);
926 			getnanouptime(&outfvdat->last_local_modify);
927 		}
928 		fuse_vnode_update(invp, FN_ATIMECHANGE);
929 		fuse_vnode_update(outvp, FN_MTIMECHANGE | FN_CTIMECHANGE);
930 	}
931 	fdisp_destroy(&fdi);
932 
933 unlock:
934 	if (invp != outvp)
935 		VOP_UNLOCK(invp);
936 	VOP_UNLOCK(outvp);
937 
938 	if (err == ENOSYS) {
939 		fsess_set_notimpl(mp, FUSE_COPY_FILE_RANGE);
940 fallback:
941 		err = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp,
942 		    ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags,
943 		    ap->a_incred, ap->a_outcred, ap->a_fsizetd);
944 	}
945 
946 	/*
947 	 * No need to call vn_rlimit_fsizex_res before return, since the uio is
948 	 * local.
949 	 */
950 	return (err);
951 }
952 
953 static void
954 fdisp_make_mknod_for_fallback(
955 	struct fuse_dispatcher *fdip,
956 	struct componentname *cnp,
957 	struct vnode *dvp,
958 	uint64_t parentnid,
959 	struct thread *td,
960 	struct ucred *cred,
961 	mode_t mode,
962 	enum fuse_opcode *op)
963 {
964 	struct fuse_mknod_in *fmni;
965 
966 	fdisp_init(fdip, sizeof(*fmni) + cnp->cn_namelen + 1);
967 	*op = FUSE_MKNOD;
968 	fdisp_make(fdip, *op, vnode_mount(dvp), parentnid, td, cred);
969 	fmni = fdip->indata;
970 	fmni->mode = mode;
971 	fmni->rdev = 0;
972 	memcpy((char *)fdip->indata + sizeof(*fmni), cnp->cn_nameptr,
973 	    cnp->cn_namelen);
974 	((char *)fdip->indata)[sizeof(*fmni) + cnp->cn_namelen] = '\0';
975 }
976 /*
977     struct vnop_create_args {
978 	struct vnode *a_dvp;
979 	struct vnode **a_vpp;
980 	struct componentname *a_cnp;
981 	struct vattr *a_vap;
982     };
983 */
984 static int
985 fuse_vnop_create(struct vop_create_args *ap)
986 {
987 	struct vnode *dvp = ap->a_dvp;
988 	struct vnode **vpp = ap->a_vpp;
989 	struct componentname *cnp = ap->a_cnp;
990 	struct vattr *vap = ap->a_vap;
991 	struct thread *td = curthread;
992 	struct ucred *cred = cnp->cn_cred;
993 
994 	struct fuse_data *data;
995 	struct fuse_create_in *fci;
996 	struct fuse_entry_out *feo;
997 	struct fuse_open_out *foo;
998 	struct fuse_dispatcher fdi, fdi2;
999 	struct fuse_dispatcher *fdip = &fdi;
1000 	struct fuse_dispatcher *fdip2 = NULL;
1001 
1002 	int err;
1003 
1004 	struct mount *mp = vnode_mount(dvp);
1005 	data = fuse_get_mpdata(mp);
1006 	uint64_t parentnid = VTOFUD(dvp)->nid;
1007 	mode_t mode = MAKEIMODE(vap->va_type, vap->va_mode);
1008 	enum fuse_opcode op;
1009 	int flags;
1010 
1011 	if (fuse_isdeadfs(dvp))
1012 		return ENXIO;
1013 
1014 	/* FUSE expects sockets to be created with FUSE_MKNOD */
1015 	if (vap->va_type == VSOCK)
1016 		return fuse_internal_mknod(dvp, vpp, cnp, vap);
1017 
1018 	/*
1019 	 * VOP_CREATE doesn't tell us the open(2) flags, so we guess.  Only a
1020 	 * writable mode makes sense, and we might as well include readability
1021 	 * too.
1022 	 */
1023 	flags = O_RDWR;
1024 
1025 	bzero(&fdi, sizeof(fdi));
1026 
1027 	if (vap->va_type != VREG)
1028 		return (EINVAL);
1029 
1030 	if (fsess_not_impl(mp, FUSE_CREATE) || vap->va_type == VSOCK) {
1031 		/* Fallback to FUSE_MKNOD/FUSE_OPEN */
1032 		fdisp_make_mknod_for_fallback(fdip, cnp, dvp, parentnid, td,
1033 			cred, mode, &op);
1034 	} else {
1035 		/* Use FUSE_CREATE */
1036 		size_t insize;
1037 
1038 		op = FUSE_CREATE;
1039 		fdisp_init(fdip, sizeof(*fci) + cnp->cn_namelen + 1);
1040 		fdisp_make(fdip, op, vnode_mount(dvp), parentnid, td, cred);
1041 		fci = fdip->indata;
1042 		fci->mode = mode;
1043 		fci->flags = O_CREAT | flags;
1044 		if (fuse_libabi_geq(data, 7, 12)) {
1045 			insize = sizeof(*fci);
1046 			fci->umask = td->td_proc->p_pd->pd_cmask;
1047 		} else {
1048 			insize = sizeof(struct fuse_open_in);
1049 		}
1050 
1051 		memcpy((char *)fdip->indata + insize, cnp->cn_nameptr,
1052 		    cnp->cn_namelen);
1053 		((char *)fdip->indata)[insize + cnp->cn_namelen] = '\0';
1054 	}
1055 
1056 	err = fdisp_wait_answ(fdip);
1057 
1058 	if (err) {
1059 		if (err == ENOSYS && op == FUSE_CREATE) {
1060 			fsess_set_notimpl(mp, FUSE_CREATE);
1061 			fdisp_destroy(fdip);
1062 			fdisp_make_mknod_for_fallback(fdip, cnp, dvp,
1063 				parentnid, td, cred, mode, &op);
1064 			err = fdisp_wait_answ(fdip);
1065 		}
1066 		if (err)
1067 			goto out;
1068 	}
1069 
1070 	feo = fdip->answ;
1071 
1072 	if ((err = fuse_internal_checkentry(feo, vap->va_type))) {
1073 		goto out;
1074 	}
1075 
1076 	if (op == FUSE_CREATE) {
1077 		if (fuse_libabi_geq(data, 7, 9))
1078 			foo = (struct fuse_open_out*)(feo + 1);
1079 		else
1080 			foo = (struct fuse_open_out*)((char*)feo +
1081 				FUSE_COMPAT_ENTRY_OUT_SIZE);
1082 	} else {
1083 		/* Issue a separate FUSE_OPEN */
1084 		struct fuse_open_in *foi;
1085 
1086 		fdip2 = &fdi2;
1087 		fdisp_init(fdip2, sizeof(*foi));
1088 		fdisp_make(fdip2, FUSE_OPEN, vnode_mount(dvp), feo->nodeid, td,
1089 			cred);
1090 		foi = fdip2->indata;
1091 		foi->flags = flags;
1092 		err = fdisp_wait_answ(fdip2);
1093 		if (err)
1094 			goto out;
1095 		foo = fdip2->answ;
1096 	}
1097 	err = fuse_vnode_get(mp, feo, feo->nodeid, dvp, vpp, cnp, vap->va_type);
1098 	if (err) {
1099 		struct fuse_release_in *fri;
1100 		uint64_t nodeid = feo->nodeid;
1101 		uint64_t fh_id = foo->fh;
1102 
1103 		fdisp_destroy(fdip);
1104 		fdisp_init(fdip, sizeof(*fri));
1105 		fdisp_make(fdip, FUSE_RELEASE, mp, nodeid, td, cred);
1106 		fri = fdip->indata;
1107 		fri->fh = fh_id;
1108 		fri->flags = flags;
1109 		fuse_insert_callback(fdip->tick, fuse_internal_forget_callback);
1110 		fuse_insert_message(fdip->tick, false);
1111 		goto out;
1112 	}
1113 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnop_create");
1114 	fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid,
1115 		feo->attr_valid_nsec, NULL, true);
1116 
1117 	fuse_filehandle_init(*vpp, FUFH_RDWR, NULL, td, cred, foo);
1118 	fuse_vnode_open(*vpp, foo->open_flags, td);
1119 	/*
1120 	 * Purge the parent's attribute cache because the daemon should've
1121 	 * updated its mtime and ctime
1122 	 */
1123 	fuse_vnode_clear_attr_cache(dvp);
1124 	cache_purge_negative(dvp);
1125 
1126 out:
1127 	if (fdip2)
1128 		fdisp_destroy(fdip2);
1129 	fdisp_destroy(fdip);
1130 	return err;
1131 }
1132 
1133 /*
1134     struct vnop_fdatasync_args {
1135 	struct vop_generic_args a_gen;
1136 	struct vnode * a_vp;
1137 	struct thread * a_td;
1138     };
1139 */
1140 static int
1141 fuse_vnop_fdatasync(struct vop_fdatasync_args *ap)
1142 {
1143 	struct vnode *vp = ap->a_vp;
1144 	struct thread *td = ap->a_td;
1145 	int waitfor = MNT_WAIT;
1146 
1147 	int err = 0;
1148 
1149 	if (fuse_isdeadfs(vp)) {
1150 		return 0;
1151 	}
1152 	if ((err = vop_stdfdatasync_buf(ap)))
1153 		return err;
1154 
1155 	return fuse_internal_fsync(vp, td, waitfor, true);
1156 }
1157 
1158 /*
1159     struct vnop_fsync_args {
1160 	struct vop_generic_args a_gen;
1161 	struct vnode * a_vp;
1162 	int  a_waitfor;
1163 	struct thread * a_td;
1164     };
1165 */
1166 static int
1167 fuse_vnop_fsync(struct vop_fsync_args *ap)
1168 {
1169 	struct vnode *vp = ap->a_vp;
1170 	struct thread *td = ap->a_td;
1171 	int waitfor = ap->a_waitfor;
1172 	int err = 0;
1173 
1174 	if (fuse_isdeadfs(vp)) {
1175 		return 0;
1176 	}
1177 	if ((err = vop_stdfsync(ap)))
1178 		return err;
1179 
1180 	return fuse_internal_fsync(vp, td, waitfor, false);
1181 }
1182 
1183 /*
1184     struct vnop_getattr_args {
1185 	struct vnode *a_vp;
1186 	struct vattr *a_vap;
1187 	struct ucred *a_cred;
1188 	struct thread *a_td;
1189     };
1190 */
1191 static int
1192 fuse_vnop_getattr(struct vop_getattr_args *ap)
1193 {
1194 	struct vnode *vp = ap->a_vp;
1195 	struct vattr *vap = ap->a_vap;
1196 	struct ucred *cred = ap->a_cred;
1197 	struct thread *td = curthread;
1198 
1199 	int err = 0;
1200 	int dataflags;
1201 
1202 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
1203 
1204 	/* Note that we are not bailing out on a dead file system just yet. */
1205 
1206 	if (!(dataflags & FSESS_INITED)) {
1207 		if (!vnode_isvroot(vp)) {
1208 			fdata_set_dead(fuse_get_mpdata(vnode_mount(vp)));
1209 			err = ENOTCONN;
1210 			return err;
1211 		} else {
1212 			goto fake;
1213 		}
1214 	}
1215 	err = fuse_internal_getattr(vp, vap, cred, td);
1216 	if (err == ENOTCONN && vnode_isvroot(vp)) {
1217 		/* see comment in fuse_vfsop_statfs() */
1218 		goto fake;
1219 	} else {
1220 		return err;
1221 	}
1222 
1223 fake:
1224 	bzero(vap, sizeof(*vap));
1225 	vap->va_type = vnode_vtype(vp);
1226 
1227 	return 0;
1228 }
1229 
1230 /*
1231     struct vnop_inactive_args {
1232 	struct vnode *a_vp;
1233     };
1234 */
1235 static int
1236 fuse_vnop_inactive(struct vop_inactive_args *ap)
1237 {
1238 	struct vnode *vp = ap->a_vp;
1239 	struct thread *td = curthread;
1240 
1241 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1242 	struct fuse_filehandle *fufh, *fufh_tmp;
1243 
1244 	int need_flush = 1;
1245 
1246 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1247 		if (need_flush && vp->v_type == VREG) {
1248 			if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) {
1249 				fuse_vnode_savesize(vp, NULL, 0);
1250 			}
1251 			if ((fvdat->flag & FN_REVOKED) != 0)
1252 				fuse_io_invalbuf(vp, td);
1253 			else
1254 				fuse_io_flushbuf(vp, MNT_WAIT, td);
1255 			need_flush = 0;
1256 		}
1257 		fuse_filehandle_close(vp, fufh, td, NULL);
1258 	}
1259 
1260 	if ((fvdat->flag & FN_REVOKED) != 0)
1261 		vrecycle(vp);
1262 
1263 	return 0;
1264 }
1265 
1266 /*
1267     struct vnop_ioctl_args {
1268 	struct vnode *a_vp;
1269 	u_long a_command;
1270 	caddr_t a_data;
1271 	int a_fflag;
1272 	struct ucred *a_cred;
1273 	struct thread *a_td;
1274     };
1275 */
1276 static int
1277 fuse_vnop_ioctl(struct vop_ioctl_args *ap)
1278 {
1279 	struct vnode *vp = ap->a_vp;
1280 	struct mount *mp = vnode_mount(vp);
1281 	struct ucred *cred = ap->a_cred;
1282 	off_t *offp;
1283 	pid_t pid = ap->a_td->td_proc->p_pid;
1284 	int err;
1285 
1286 	switch (ap->a_command) {
1287 	case FIOSEEKDATA:
1288 	case FIOSEEKHOLE:
1289 		/* Call FUSE_LSEEK, if we can, or fall back to vop_stdioctl */
1290 		if (fsess_maybe_impl(mp, FUSE_LSEEK)) {
1291 			int whence;
1292 
1293 			offp = ap->a_data;
1294 			if (ap->a_command == FIOSEEKDATA)
1295 				whence = SEEK_DATA;
1296 			else
1297 				whence = SEEK_HOLE;
1298 
1299 			vn_lock(vp, LK_SHARED | LK_RETRY);
1300 			err = fuse_vnop_do_lseek(vp, ap->a_td, cred, pid, offp,
1301 			    whence);
1302 			VOP_UNLOCK(vp);
1303 		}
1304 		if (fsess_not_impl(mp, FUSE_LSEEK))
1305 			err = vop_stdioctl(ap);
1306 		break;
1307 	default:
1308 		/* TODO: implement FUSE_IOCTL */
1309 		err = ENOTTY;
1310 		break;
1311 	}
1312 	return (err);
1313 }
1314 
1315 
1316 /*
1317     struct vnop_link_args {
1318 	struct vnode *a_tdvp;
1319 	struct vnode *a_vp;
1320 	struct componentname *a_cnp;
1321     };
1322 */
1323 static int
1324 fuse_vnop_link(struct vop_link_args *ap)
1325 {
1326 	struct vnode *vp = ap->a_vp;
1327 	struct vnode *tdvp = ap->a_tdvp;
1328 	struct componentname *cnp = ap->a_cnp;
1329 
1330 	struct vattr *vap = VTOVA(vp);
1331 
1332 	struct fuse_dispatcher fdi;
1333 	struct fuse_entry_out *feo;
1334 	struct fuse_link_in fli;
1335 
1336 	int err;
1337 
1338 	if (fuse_isdeadfs(vp)) {
1339 		return ENXIO;
1340 	}
1341 	if (vnode_mount(tdvp) != vnode_mount(vp)) {
1342 		return EXDEV;
1343 	}
1344 
1345 	/*
1346 	 * This is a seatbelt check to protect naive userspace filesystems from
1347 	 * themselves and the limitations of the FUSE IPC protocol.  If a
1348 	 * filesystem does not allow attribute caching, assume it is capable of
1349 	 * validating that nlink does not overflow.
1350 	 */
1351 	if (vap != NULL && vap->va_nlink >= FUSE_LINK_MAX)
1352 		return EMLINK;
1353 	fli.oldnodeid = VTOI(vp);
1354 
1355 	fdisp_init(&fdi, 0);
1356 	fuse_internal_newentry_makerequest(vnode_mount(tdvp), VTOI(tdvp), cnp,
1357 	    FUSE_LINK, &fli, sizeof(fli), &fdi);
1358 	if ((err = fdisp_wait_answ(&fdi))) {
1359 		goto out;
1360 	}
1361 	feo = fdi.answ;
1362 
1363 	if (fli.oldnodeid != feo->nodeid) {
1364 		struct fuse_data *data = fuse_get_mpdata(vnode_mount(vp));
1365 		fuse_warn(data, FSESS_WARN_ILLEGAL_INODE,
1366 			"Assigned wrong inode for a hard link.");
1367 		fuse_vnode_clear_attr_cache(vp);
1368 		fuse_vnode_clear_attr_cache(tdvp);
1369 		err = EIO;
1370 		goto out;
1371 	}
1372 
1373 	err = fuse_internal_checkentry(feo, vnode_vtype(vp));
1374 	if (!err) {
1375 		/*
1376 		 * Purge the parent's attribute cache because the daemon
1377 		 * should've updated its mtime and ctime
1378 		 */
1379 		fuse_vnode_clear_attr_cache(tdvp);
1380 		fuse_internal_cache_attrs(vp, &feo->attr, feo->attr_valid,
1381 			feo->attr_valid_nsec, NULL, true);
1382 	}
1383 out:
1384 	fdisp_destroy(&fdi);
1385 	return err;
1386 }
1387 
1388 struct fuse_lookup_alloc_arg {
1389 	struct fuse_entry_out *feo;
1390 	struct componentname *cnp;
1391 	uint64_t nid;
1392 	__enum_uint8(vtype) vtyp;
1393 };
1394 
1395 /* Callback for vn_get_ino */
1396 static int
1397 fuse_lookup_alloc(struct mount *mp, void *arg, int lkflags, struct vnode **vpp)
1398 {
1399 	struct fuse_lookup_alloc_arg *flaa = arg;
1400 
1401 	return fuse_vnode_get(mp, flaa->feo, flaa->nid, NULL, vpp, flaa->cnp,
1402 		flaa->vtyp);
1403 }
1404 
1405 SDT_PROBE_DEFINE3(fusefs, , vnops, cache_lookup,
1406 	"int", "struct timespec*", "struct timespec*");
1407 /*
1408     struct vnop_lookup_args {
1409 	struct vnodeop_desc *a_desc;
1410 	struct vnode *a_dvp;
1411 	struct vnode **a_vpp;
1412 	struct componentname *a_cnp;
1413     };
1414 */
1415 int
1416 fuse_vnop_lookup(struct vop_lookup_args *ap)
1417 {
1418 	struct vnode *dvp = ap->a_dvp;
1419 	struct vnode **vpp = ap->a_vpp;
1420 	struct componentname *cnp = ap->a_cnp;
1421 	struct thread *td = curthread;
1422 	struct ucred *cred = cnp->cn_cred;
1423 	struct timespec now;
1424 
1425 	int nameiop = cnp->cn_nameiop;
1426 	int flags = cnp->cn_flags;
1427 	int islastcn = flags & ISLASTCN;
1428 	struct mount *mp = vnode_mount(dvp);
1429 	struct fuse_data *data = fuse_get_mpdata(mp);
1430 	int default_permissions = data->dataflags & FSESS_DEFAULT_PERMISSIONS;
1431 	bool is_dot;
1432 
1433 	int err = 0;
1434 	int lookup_err = 0;
1435 	struct vnode *vp = NULL;
1436 
1437 	struct fuse_dispatcher fdi;
1438 	bool did_lookup = false;
1439 	struct fuse_entry_out *feo = NULL;
1440 	__enum_uint8(vtype) vtyp;	/* vnode type of target */
1441 
1442 	uint64_t nid;
1443 
1444 	if (fuse_isdeadfs(dvp)) {
1445 		*vpp = NULL;
1446 		return ENXIO;
1447 	}
1448 	if (!vnode_isdir(dvp))
1449 		return ENOTDIR;
1450 
1451 	if (islastcn && vfs_isrdonly(mp) && (nameiop != LOOKUP))
1452 		return EROFS;
1453 
1454 	if ((cnp->cn_flags & NOEXECCHECK) != 0)
1455 		cnp->cn_flags &= ~NOEXECCHECK;
1456 	else if ((err = fuse_internal_access(dvp, VEXEC, td, cred)))
1457 		return err;
1458 
1459 	is_dot = cnp->cn_namelen == 1 && *(cnp->cn_nameptr) == '.';
1460 	if ((flags & ISDOTDOT) && !(data->dataflags & FSESS_EXPORT_SUPPORT))
1461 	{
1462 		if (!(VTOFUD(dvp)->flag & FN_PARENT_NID)) {
1463 			/*
1464 			 * Since the file system doesn't support ".." lookups,
1465 			 * we have no way to find this entry.
1466 			 */
1467 			return ESTALE;
1468 		}
1469 		nid = VTOFUD(dvp)->parent_nid;
1470 		if (nid == 0)
1471 			return ENOENT;
1472 		/* .. is obviously a directory */
1473 		vtyp = VDIR;
1474 	} else if (is_dot) {
1475 		nid = VTOI(dvp);
1476 		/* . is obviously a directory */
1477 		vtyp = VDIR;
1478 	} else {
1479 		struct timespec timeout;
1480 		int ncpticks; /* here to accommodate for API contract */
1481 
1482 		err = cache_lookup(dvp, vpp, cnp, &timeout, &ncpticks);
1483 		getnanouptime(&now);
1484 		SDT_PROBE3(fusefs, , vnops, cache_lookup, err, &timeout, &now);
1485 		switch (err) {
1486 		case -1:		/* positive match */
1487 			if (timespeccmp(&timeout, &now, >)) {
1488 				counter_u64_add(fuse_lookup_cache_hits, 1);
1489 			} else {
1490 				/* Cache timeout */
1491 				counter_u64_add(fuse_lookup_cache_misses, 1);
1492 				bintime_clear(
1493 					&VTOFUD(*vpp)->entry_cache_timeout);
1494 				cache_purge(*vpp);
1495 				if (dvp != *vpp)
1496 					vput(*vpp);
1497 				else
1498 					vrele(*vpp);
1499 				*vpp = NULL;
1500 				break;
1501 			}
1502 			return 0;
1503 
1504 		case 0:		/* no match in cache */
1505 			counter_u64_add(fuse_lookup_cache_misses, 1);
1506 			break;
1507 
1508 		case ENOENT:		/* negative match */
1509 			if (timespeccmp(&timeout, &now, <=)) {
1510 				/* Cache timeout */
1511 				cache_purge_negative(dvp);
1512 				break;
1513 			}
1514 			/* fall through */
1515 		default:
1516 			return err;
1517 		}
1518 
1519 		fdisp_init(&fdi, cnp->cn_namelen + 1);
1520 		fdisp_make(&fdi, FUSE_LOOKUP, mp, VTOI(dvp), td, cred);
1521 
1522 		memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
1523 		((char *)fdi.indata)[cnp->cn_namelen] = '\0';
1524 		lookup_err = fdisp_wait_answ(&fdi);
1525 		did_lookup = true;
1526 
1527 		if (!lookup_err) {
1528 			/* lookup call succeeded */
1529 			feo = (struct fuse_entry_out *)fdi.answ;
1530 			nid = feo->nodeid;
1531 			if (nid == 0) {
1532 				/* zero nodeid means ENOENT and cache it */
1533 				struct timespec timeout;
1534 
1535 				fdi.answ_stat = ENOENT;
1536 				lookup_err = ENOENT;
1537 				if (cnp->cn_flags & MAKEENTRY) {
1538 					fuse_validity_2_timespec(feo, &timeout);
1539 					/* Use the same entry_time for .. as for
1540 					 * the file itself.  That doesn't honor
1541 					 * exactly what the fuse server tells
1542 					 * us, but to do otherwise would require
1543 					 * another cache lookup at this point.
1544 					 */
1545 					struct timespec *dtsp = NULL;
1546 					cache_enter_time(dvp, *vpp, cnp,
1547 						&timeout, dtsp);
1548 				}
1549 			}
1550 			vtyp = IFTOVT(feo->attr.mode);
1551 		}
1552 		if (lookup_err && (!fdi.answ_stat || lookup_err != ENOENT)) {
1553 			fdisp_destroy(&fdi);
1554 			return lookup_err;
1555 		}
1556 	}
1557 	/* lookup_err, if non-zero, must be ENOENT at this point */
1558 
1559 	if (lookup_err) {
1560 		/* Entry not found */
1561 		if ((nameiop == CREATE || nameiop == RENAME) && islastcn) {
1562 			if (default_permissions)
1563 				err = fuse_internal_access(dvp, VWRITE, td,
1564 				    cred);
1565 			else
1566 				err = 0;
1567 			if (!err) {
1568 				err = EJUSTRETURN;
1569 			}
1570 		} else {
1571 			err = ENOENT;
1572 		}
1573 	} else {
1574 		/* Entry was found */
1575 		if (flags & ISDOTDOT) {
1576 			struct fuse_lookup_alloc_arg flaa;
1577 
1578 			flaa.nid = nid;
1579 			flaa.feo = feo;
1580 			flaa.cnp = cnp;
1581 			flaa.vtyp = vtyp;
1582 			err = vn_vget_ino_gen(dvp, fuse_lookup_alloc, &flaa, 0,
1583 				&vp);
1584 			*vpp = vp;
1585 		} else if (nid == VTOI(dvp)) {
1586 			if (is_dot) {
1587 				vref(dvp);
1588 				*vpp = dvp;
1589 			} else {
1590 				fuse_warn(fuse_get_mpdata(mp),
1591 				    FSESS_WARN_ILLEGAL_INODE,
1592 				    "Assigned same inode to both parent and "
1593 				    "child.");
1594 				err = EIO;
1595 			}
1596 
1597 		} else {
1598 			struct fuse_vnode_data *fvdat;
1599 
1600 			err = fuse_vnode_get(vnode_mount(dvp), feo, nid, dvp,
1601 			    &vp, cnp, vtyp);
1602 			if (err)
1603 				goto out;
1604 			*vpp = vp;
1605 			fvdat = VTOFUD(vp);
1606 
1607 			MPASS(feo != NULL);
1608 			if (timespeccmp(&now, &fvdat->last_local_modify, >)) {
1609 				/*
1610 				 * Attributes from the server are definitely
1611 				 * newer than the last attributes we sent to
1612 				 * the server, so cache them.
1613 				 */
1614 				fuse_internal_cache_attrs(*vpp, &feo->attr,
1615 					feo->attr_valid, feo->attr_valid_nsec,
1616 					NULL, true);
1617 			}
1618 			fuse_validity_2_bintime(feo->entry_valid,
1619 				feo->entry_valid_nsec,
1620 				&fvdat->entry_cache_timeout);
1621 
1622 			if ((nameiop == DELETE || nameiop == RENAME) &&
1623 				islastcn && default_permissions)
1624 			{
1625 				struct vattr dvattr;
1626 
1627 				err = fuse_internal_access(dvp, VWRITE, td,
1628 					cred);
1629 				if (err != 0)
1630 					goto out;
1631 				/*
1632 				 * if the parent's sticky bit is set, check
1633 				 * whether we're allowed to remove the file.
1634 				 * Need to figure out the vnode locking to make
1635 				 * this work.
1636 				 */
1637 				fuse_internal_getattr(dvp, &dvattr, cred, td);
1638 				if ((dvattr.va_mode & S_ISTXT) &&
1639 					fuse_internal_access(dvp, VADMIN, td,
1640 						cred) &&
1641 					fuse_internal_access(*vpp, VADMIN, td,
1642 						cred)) {
1643 					err = EPERM;
1644 					goto out;
1645 				}
1646 			}
1647 		}
1648 	}
1649 out:
1650 	if (err) {
1651 		if (vp != NULL && dvp != vp)
1652 			vput(vp);
1653 		else if (vp != NULL)
1654 			vrele(vp);
1655 		*vpp = NULL;
1656 	}
1657 	if (did_lookup)
1658 		fdisp_destroy(&fdi);
1659 
1660 	return err;
1661 }
1662 
1663 /*
1664     struct vnop_mkdir_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_mkdir(struct vop_mkdir_args *ap)
1673 {
1674 	struct vnode *dvp = ap->a_dvp;
1675 	struct vnode **vpp = ap->a_vpp;
1676 	struct componentname *cnp = ap->a_cnp;
1677 	struct vattr *vap = ap->a_vap;
1678 
1679 	struct fuse_mkdir_in fmdi;
1680 
1681 	if (fuse_isdeadfs(dvp)) {
1682 		return ENXIO;
1683 	}
1684 	fmdi.mode = MAKEIMODE(vap->va_type, vap->va_mode);
1685 	fmdi.umask = curthread->td_proc->p_pd->pd_cmask;
1686 
1687 	return (fuse_internal_newentry(dvp, vpp, cnp, FUSE_MKDIR, &fmdi,
1688 	    sizeof(fmdi), VDIR));
1689 }
1690 
1691 /*
1692     struct vnop_mknod_args {
1693 	struct vnode *a_dvp;
1694 	struct vnode **a_vpp;
1695 	struct componentname *a_cnp;
1696 	struct vattr *a_vap;
1697     };
1698 */
1699 static int
1700 fuse_vnop_mknod(struct vop_mknod_args *ap)
1701 {
1702 
1703 	struct vnode *dvp = ap->a_dvp;
1704 	struct vnode **vpp = ap->a_vpp;
1705 	struct componentname *cnp = ap->a_cnp;
1706 	struct vattr *vap = ap->a_vap;
1707 
1708 	if (fuse_isdeadfs(dvp))
1709 		return ENXIO;
1710 
1711 	return fuse_internal_mknod(dvp, vpp, cnp, vap);
1712 }
1713 
1714 /*
1715     struct vop_open_args {
1716 	struct vnode *a_vp;
1717 	int  a_mode;
1718 	struct ucred *a_cred;
1719 	struct thread *a_td;
1720 	int a_fdidx; / struct file *a_fp;
1721     };
1722 */
1723 static int
1724 fuse_vnop_open(struct vop_open_args *ap)
1725 {
1726 	struct vnode *vp = ap->a_vp;
1727 	int a_mode = ap->a_mode;
1728 	struct thread *td = ap->a_td;
1729 	struct ucred *cred = ap->a_cred;
1730 	pid_t pid = td->td_proc->p_pid;
1731 
1732 	if (fuse_isdeadfs(vp))
1733 		return ENXIO;
1734 	if (vp->v_type == VCHR || vp->v_type == VBLK || vp->v_type == VFIFO)
1735 		return (EOPNOTSUPP);
1736 	if ((a_mode & (FREAD | FWRITE | FEXEC)) == 0)
1737 		return EINVAL;
1738 
1739 	if (fuse_filehandle_validrw(vp, a_mode, cred, pid)) {
1740 		fuse_vnode_open(vp, 0, td);
1741 		return 0;
1742 	}
1743 
1744 	return fuse_filehandle_open(vp, a_mode, NULL, td, cred);
1745 }
1746 
1747 static int
1748 fuse_vnop_pathconf(struct vop_pathconf_args *ap)
1749 {
1750 	struct vnode *vp = ap->a_vp;
1751 	struct mount *mp;
1752 
1753 	switch (ap->a_name) {
1754 	case _PC_FILESIZEBITS:
1755 		*ap->a_retval = 64;
1756 		return (0);
1757 	case _PC_NAME_MAX:
1758 		*ap->a_retval = NAME_MAX;
1759 		return (0);
1760 	case _PC_LINK_MAX:
1761 		*ap->a_retval = MIN(LONG_MAX, FUSE_LINK_MAX);
1762 		return (0);
1763 	case _PC_SYMLINK_MAX:
1764 		*ap->a_retval = MAXPATHLEN;
1765 		return (0);
1766 	case _PC_NO_TRUNC:
1767 		*ap->a_retval = 1;
1768 		return (0);
1769 	case _PC_MIN_HOLE_SIZE:
1770 		/*
1771 		 * The FUSE protocol provides no mechanism for a server to
1772 		 * report _PC_MIN_HOLE_SIZE.  It's a protocol bug.  Instead,
1773 		 * return EINVAL if the server does not support FUSE_LSEEK, or
1774 		 * 1 if it does.
1775 		 */
1776 		mp = vnode_mount(vp);
1777 		if (!fsess_is_impl(mp, FUSE_LSEEK) &&
1778 		    !fsess_not_impl(mp, FUSE_LSEEK)) {
1779 			off_t offset = 0;
1780 
1781 			/* Issue a FUSE_LSEEK to find out if it's implemented */
1782 			fuse_vnop_do_lseek(vp, curthread, curthread->td_ucred,
1783 			    curthread->td_proc->p_pid, &offset, SEEK_DATA);
1784 		}
1785 
1786 		if (fsess_is_impl(mp, FUSE_LSEEK)) {
1787 			*ap->a_retval = 1;
1788 			return (0);
1789 		} else {
1790 			/*
1791 			 * Probably FUSE_LSEEK is not implemented.  It might
1792 			 * be, if the FUSE_LSEEK above returned an error like
1793 			 * EACCES, but in that case we can't tell, so it's
1794 			 * safest to report EINVAL anyway.
1795 			 */
1796 			return (EINVAL);
1797 		}
1798 	default:
1799 		return (vop_stdpathconf(ap));
1800 	}
1801 }
1802 
1803 SDT_PROBE_DEFINE3(fusefs, , vnops, filehandles_closed, "struct vnode*",
1804     "struct uio*", "struct ucred*");
1805 /*
1806     struct vnop_read_args {
1807 	struct vnode *a_vp;
1808 	struct uio *a_uio;
1809 	int  a_ioflag;
1810 	struct ucred *a_cred;
1811     };
1812 */
1813 static int
1814 fuse_vnop_read(struct vop_read_args *ap)
1815 {
1816 	struct vnode *vp = ap->a_vp;
1817 	struct uio *uio = ap->a_uio;
1818 	int ioflag = ap->a_ioflag;
1819 	struct ucred *cred = ap->a_cred;
1820 	pid_t pid = curthread->td_proc->p_pid;
1821 	struct fuse_filehandle *fufh;
1822 	int err;
1823 	bool closefufh = false, directio;
1824 
1825 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
1826 
1827 	if (fuse_isdeadfs(vp)) {
1828 		return ENXIO;
1829 	}
1830 
1831 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
1832 		ioflag |= IO_DIRECT;
1833 	}
1834 
1835 	err = fuse_filehandle_getrw(vp, FREAD, &fufh, cred, pid);
1836 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
1837 		/*
1838 		 * nfsd will do I/O without first doing VOP_OPEN.  We
1839 		 * must implicitly open the file here
1840 		 */
1841 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1842 		closefufh = true;
1843 	}
1844 	if (err) {
1845 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
1846 		return err;
1847 	}
1848 
1849 	/*
1850          * Ideally, when the daemon asks for direct io at open time, the
1851          * standard file flag should be set according to this, so that would
1852          * just change the default mode, which later on could be changed via
1853          * fcntl(2).
1854          * But this doesn't work, the O_DIRECT flag gets cleared at some point
1855          * (don't know where). So to make any use of the Fuse direct_io option,
1856          * we hardwire it into the file's private data (similarly to Linux,
1857          * btw.).
1858          */
1859 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
1860 
1861 	fuse_vnode_update(vp, FN_ATIMECHANGE);
1862 	if (directio) {
1863 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct read of vnode");
1864 		err = fuse_read_directbackend(vp, uio, cred, fufh);
1865 	} else {
1866 		SDT_PROBE2(fusefs, , vnops, trace, 1, "buffered read of vnode");
1867 		err = fuse_read_biobackend(vp, uio, ioflag, cred, fufh, pid);
1868 	}
1869 
1870 	if (closefufh)
1871 		fuse_filehandle_close(vp, fufh, curthread, cred);
1872 
1873 	return (err);
1874 }
1875 
1876 /*
1877     struct vnop_readdir_args {
1878 	struct vnode *a_vp;
1879 	struct uio *a_uio;
1880 	struct ucred *a_cred;
1881 	int *a_eofflag;
1882 	int *a_ncookies;
1883 	uint64_t **a_cookies;
1884     };
1885 */
1886 static int
1887 fuse_vnop_readdir(struct vop_readdir_args *ap)
1888 {
1889 	struct vnode *vp = ap->a_vp;
1890 	struct uio *uio = ap->a_uio;
1891 	struct ucred *cred = ap->a_cred;
1892 	struct fuse_filehandle *fufh = NULL;
1893 	struct mount *mp = vnode_mount(vp);
1894 	struct fuse_iov cookediov;
1895 	int err = 0;
1896 	uint64_t *cookies;
1897 	ssize_t tresid;
1898 	int ncookies;
1899 	bool closefufh = false;
1900 	pid_t pid = curthread->td_proc->p_pid;
1901 
1902 	if (ap->a_eofflag)
1903 		*ap->a_eofflag = 0;
1904 	if (fuse_isdeadfs(vp)) {
1905 		return ENXIO;
1906 	}
1907 	if (				/* XXXIP ((uio_iovcnt(uio) > 1)) || */
1908 	    (uio_resid(uio) < sizeof(struct dirent))) {
1909 		return EINVAL;
1910 	}
1911 
1912 	tresid = uio->uio_resid;
1913 	err = fuse_filehandle_get_dir(vp, &fufh, cred, pid);
1914 	if (err == EBADF && mp->mnt_flag & MNT_EXPORTED) {
1915 		KASSERT(fuse_get_mpdata(mp)->dataflags
1916 				& FSESS_NO_OPENDIR_SUPPORT,
1917 			("FUSE file systems that don't set "
1918 			 "FUSE_NO_OPENDIR_SUPPORT should not be exported"));
1919 		/*
1920 		 * nfsd will do VOP_READDIR without first doing VOP_OPEN.  We
1921 		 * must implicitly open the directory here.
1922 		 */
1923 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1924 		closefufh = true;
1925 	}
1926 	if (err)
1927 		return (err);
1928 	if (ap->a_ncookies != NULL) {
1929 		ncookies = uio->uio_resid /
1930 			(offsetof(struct dirent, d_name) + 4) + 1;
1931 		cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
1932 		*ap->a_ncookies = ncookies;
1933 		*ap->a_cookies = cookies;
1934 	} else {
1935 		ncookies = 0;
1936 		cookies = NULL;
1937 	}
1938 #define DIRCOOKEDSIZE FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + MAXNAMLEN + 1)
1939 	fiov_init(&cookediov, DIRCOOKEDSIZE);
1940 
1941 	err = fuse_internal_readdir(vp, uio, fufh, &cookediov,
1942 		&ncookies, cookies);
1943 
1944 	fiov_teardown(&cookediov);
1945 	if (closefufh)
1946 		fuse_filehandle_close(vp, fufh, curthread, cred);
1947 
1948 	if (ap->a_ncookies != NULL) {
1949 		if (err == 0) {
1950 			*ap->a_ncookies -= ncookies;
1951 		} else {
1952 			free(*ap->a_cookies, M_TEMP);
1953 			*ap->a_ncookies = 0;
1954 			*ap->a_cookies = NULL;
1955 		}
1956 	}
1957 	if (err == 0 && tresid == uio->uio_resid)
1958 		*ap->a_eofflag = 1;
1959 
1960 	return err;
1961 }
1962 
1963 /*
1964     struct vnop_readlink_args {
1965 	struct vnode *a_vp;
1966 	struct uio *a_uio;
1967 	struct ucred *a_cred;
1968     };
1969 */
1970 static int
1971 fuse_vnop_readlink(struct vop_readlink_args *ap)
1972 {
1973 	struct vnode *vp = ap->a_vp;
1974 	struct uio *uio = ap->a_uio;
1975 	struct ucred *cred = ap->a_cred;
1976 
1977 	struct fuse_dispatcher fdi;
1978 	int err;
1979 
1980 	if (fuse_isdeadfs(vp)) {
1981 		return ENXIO;
1982 	}
1983 	if (!vnode_islnk(vp)) {
1984 		return EINVAL;
1985 	}
1986 	fdisp_init(&fdi, 0);
1987 	err = fdisp_simple_putget_vp(&fdi, FUSE_READLINK, vp, curthread, cred);
1988 	if (err) {
1989 		goto out;
1990 	}
1991 	if (((char *)fdi.answ)[0] == '/' &&
1992 	    fuse_get_mpdata(vnode_mount(vp))->dataflags & FSESS_PUSH_SYMLINKS_IN) {
1993 		char *mpth = vnode_mount(vp)->mnt_stat.f_mntonname;
1994 
1995 		err = uiomove(mpth, strlen(mpth), uio);
1996 	}
1997 	if (!err) {
1998 		err = uiomove(fdi.answ, fdi.iosize, uio);
1999 	}
2000 out:
2001 	fdisp_destroy(&fdi);
2002 	return err;
2003 }
2004 
2005 /*
2006     struct vnop_reclaim_args {
2007 	struct vnode *a_vp;
2008     };
2009 */
2010 static int
2011 fuse_vnop_reclaim(struct vop_reclaim_args *ap)
2012 {
2013 	struct vnode *vp = ap->a_vp;
2014 	struct thread *td = curthread;
2015 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
2016 	struct fuse_filehandle *fufh, *fufh_tmp;
2017 
2018 	if (!fvdat) {
2019 		panic("FUSE: no vnode data during recycling");
2020 	}
2021 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
2022 		printf("FUSE: vnode being reclaimed with open fufh "
2023 			"(type=%#x)", fufh->fufh_type);
2024 		fuse_filehandle_close(vp, fufh, td, NULL);
2025 	}
2026 
2027 	if (VTOI(vp) == 1) {
2028 		/*
2029 		 * Don't send FUSE_FORGET for the root inode, because
2030 		 * we never send FUSE_LOOKUP for it (see
2031 		 * fuse_vfsop_root) and we don't want the server to see
2032 		 * mismatched lookup counts.
2033 		 */
2034 		struct fuse_data *data;
2035 		struct vnode *vroot;
2036 
2037 		data = fuse_get_mpdata(vnode_mount(vp));
2038 		FUSE_LOCK();
2039 		vroot = data->vroot;
2040 		data->vroot = NULL;
2041 		FUSE_UNLOCK();
2042 		if (vroot)
2043 			vrele(vroot);
2044 	} else if (!fuse_isdeadfs(vp) && fvdat->nlookup > 0) {
2045 		fuse_internal_forget_send(vnode_mount(vp), td, NULL, VTOI(vp),
2046 		    fvdat->nlookup);
2047 	}
2048 	cache_purge(vp);
2049 	vfs_hash_remove(vp);
2050 	fuse_vnode_destroy(vp);
2051 
2052 	return 0;
2053 }
2054 
2055 /*
2056     struct vnop_remove_args {
2057 	struct vnode *a_dvp;
2058 	struct vnode *a_vp;
2059 	struct componentname *a_cnp;
2060     };
2061 */
2062 static int
2063 fuse_vnop_remove(struct vop_remove_args *ap)
2064 {
2065 	struct vnode *dvp = ap->a_dvp;
2066 	struct vnode *vp = ap->a_vp;
2067 	struct componentname *cnp = ap->a_cnp;
2068 
2069 	int err;
2070 
2071 	if (fuse_isdeadfs(vp)) {
2072 		return ENXIO;
2073 	}
2074 	if (vnode_isdir(vp)) {
2075 		return EPERM;
2076 	}
2077 
2078 	err = fuse_internal_remove(dvp, vp, cnp, FUSE_UNLINK);
2079 
2080 	return err;
2081 }
2082 
2083 /*
2084     struct vnop_rename_args {
2085 	struct vnode *a_fdvp;
2086 	struct vnode *a_fvp;
2087 	struct componentname *a_fcnp;
2088 	struct vnode *a_tdvp;
2089 	struct vnode *a_tvp;
2090 	struct componentname *a_tcnp;
2091     };
2092 */
2093 static int
2094 fuse_vnop_rename(struct vop_rename_args *ap)
2095 {
2096 	struct vnode *fdvp = ap->a_fdvp;
2097 	struct vnode *fvp = ap->a_fvp;
2098 	struct componentname *fcnp = ap->a_fcnp;
2099 	struct vnode *tdvp = ap->a_tdvp;
2100 	struct vnode *tvp = ap->a_tvp;
2101 	struct componentname *tcnp = ap->a_tcnp;
2102 	struct fuse_data *data;
2103 	bool newparent = fdvp != tdvp;
2104 	bool isdir = fvp->v_type == VDIR;
2105 	int err = 0;
2106 
2107 	if (fuse_isdeadfs(fdvp)) {
2108 		return ENXIO;
2109 	}
2110 	if (fvp->v_mount != tdvp->v_mount ||
2111 	    (tvp && fvp->v_mount != tvp->v_mount)) {
2112 		SDT_PROBE2(fusefs, , vnops, trace, 1, "cross-device rename");
2113 		err = EXDEV;
2114 		goto out;
2115 	}
2116 	cache_purge(fvp);
2117 
2118 	/*
2119 	 * FUSE library is expected to check if target directory is not
2120 	 * under the source directory in the file system tree.
2121 	 * Linux performs this check at VFS level.
2122 	 */
2123 	/*
2124 	 * If source is a directory, and it will get a new parent, user must
2125 	 * have write permission to it, so ".." can be modified.
2126 	 */
2127 	data = fuse_get_mpdata(vnode_mount(tdvp));
2128 	if (data->dataflags & FSESS_DEFAULT_PERMISSIONS && isdir && newparent) {
2129 		err = fuse_internal_access(fvp, VWRITE,
2130 			curthread, tcnp->cn_cred);
2131 		if (err)
2132 			goto out;
2133 	}
2134 	sx_xlock(&data->rename_lock);
2135 	err = fuse_internal_rename(fdvp, fcnp, tdvp, tcnp);
2136 	if (err == 0) {
2137 		if (tdvp != fdvp)
2138 			fuse_vnode_setparent(fvp, tdvp);
2139 		if (tvp != NULL)
2140 			fuse_vnode_setparent(tvp, NULL);
2141 	}
2142 	sx_unlock(&data->rename_lock);
2143 
2144 	if (tvp != NULL && tvp != fvp) {
2145 		cache_purge(tvp);
2146 	}
2147 	if (vnode_isdir(fvp)) {
2148 		if (((tvp != NULL) && vnode_isdir(tvp)) || vnode_isdir(fvp)) {
2149 			cache_purge(tdvp);
2150 		}
2151 		cache_purge(fdvp);
2152 	}
2153 out:
2154 	if (tdvp == tvp) {
2155 		vrele(tdvp);
2156 	} else {
2157 		vput(tdvp);
2158 	}
2159 	if (tvp != NULL) {
2160 		vput(tvp);
2161 	}
2162 	vrele(fdvp);
2163 	vrele(fvp);
2164 
2165 	return err;
2166 }
2167 
2168 /*
2169     struct vnop_rmdir_args {
2170 	    struct vnode *a_dvp;
2171 	    struct vnode *a_vp;
2172 	    struct componentname *a_cnp;
2173     } *ap;
2174 */
2175 static int
2176 fuse_vnop_rmdir(struct vop_rmdir_args *ap)
2177 {
2178 	struct vnode *dvp = ap->a_dvp;
2179 	struct vnode *vp = ap->a_vp;
2180 
2181 	int err;
2182 
2183 	if (fuse_isdeadfs(vp)) {
2184 		return ENXIO;
2185 	}
2186 	if (VTOFUD(vp) == VTOFUD(dvp)) {
2187 		return EINVAL;
2188 	}
2189 	err = fuse_internal_remove(dvp, vp, ap->a_cnp, FUSE_RMDIR);
2190 
2191 	return err;
2192 }
2193 
2194 /*
2195     struct vnop_setattr_args {
2196 	struct vnode *a_vp;
2197 	struct vattr *a_vap;
2198 	struct ucred *a_cred;
2199 	struct thread *a_td;
2200     };
2201 */
2202 static int
2203 fuse_vnop_setattr(struct vop_setattr_args *ap)
2204 {
2205 	struct vnode *vp = ap->a_vp;
2206 	struct vattr *vap = ap->a_vap;
2207 	struct ucred *cred = ap->a_cred;
2208 	struct thread *td = curthread;
2209 	struct mount *mp;
2210 	struct fuse_data *data;
2211 	struct vattr old_va;
2212 	int dataflags;
2213 	int err = 0, err2;
2214 	accmode_t accmode = 0;
2215 	bool checkperm;
2216 	bool drop_suid = false;
2217 
2218 	mp = vnode_mount(vp);
2219 	data = fuse_get_mpdata(mp);
2220 	dataflags = data->dataflags;
2221 	checkperm = dataflags & FSESS_DEFAULT_PERMISSIONS;
2222 
2223 	if (fuse_isdeadfs(vp)) {
2224 		return ENXIO;
2225 	}
2226 
2227 	if (vap->va_uid != (uid_t)VNOVAL) {
2228 		if (checkperm) {
2229 			/* Only root may change a file's owner */
2230 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2231 			if (err) {
2232 				/* As a special case, allow the null chown */
2233 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2234 					td);
2235 				if (err2)
2236 					return (err2);
2237 				if (vap->va_uid != old_va.va_uid)
2238 					return err;
2239 				else
2240 					accmode |= VADMIN;
2241 				drop_suid = true;
2242 			} else
2243 				accmode |= VADMIN;
2244 		} else
2245 			accmode |= VADMIN;
2246 	}
2247 	if (vap->va_gid != (gid_t)VNOVAL) {
2248 		if (checkperm && priv_check_cred(cred, PRIV_VFS_CHOWN))
2249 			drop_suid = true;
2250 		if (checkperm && !groupmember(vap->va_gid, cred))
2251 		{
2252 			/*
2253 			 * Non-root users may only chgrp to one of their own
2254 			 * groups
2255 			 */
2256 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
2257 			if (err) {
2258 				/* As a special case, allow the null chgrp */
2259 				err2 = fuse_internal_getattr(vp, &old_va, cred,
2260 					td);
2261 				if (err2)
2262 					return (err2);
2263 				if (vap->va_gid != old_va.va_gid)
2264 					return err;
2265 				accmode |= VADMIN;
2266 			} else
2267 				accmode |= VADMIN;
2268 		} else
2269 			accmode |= VADMIN;
2270 	}
2271 	if (vap->va_size != VNOVAL) {
2272 		switch (vp->v_type) {
2273 		case VDIR:
2274 			return (EISDIR);
2275 		case VLNK:
2276 		case VREG:
2277 			if (vfs_isrdonly(mp))
2278 				return (EROFS);
2279 			err = vn_rlimit_trunc(vap->va_size, td);
2280 			if (err)
2281 				return (err);
2282 			break;
2283 		default:
2284 			/*
2285 			 * According to POSIX, the result is unspecified
2286 			 * for file types other than regular files,
2287 			 * directories and shared memory objects.  We
2288 			 * don't support shared memory objects in the file
2289 			 * system, and have dubious support for truncating
2290 			 * symlinks.  Just ignore the request in other cases.
2291 			 */
2292 			return (0);
2293 		}
2294 		/* Don't set accmode.  Permission to trunc is checked upstack */
2295 	}
2296 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
2297 		if (vap->va_vaflags & VA_UTIMES_NULL)
2298 			accmode |= VWRITE;
2299 		else
2300 			accmode |= VADMIN;
2301 	}
2302 	if (drop_suid) {
2303 		if (vap->va_mode != (mode_t)VNOVAL)
2304 			vap->va_mode &= ~(S_ISUID | S_ISGID);
2305 		else {
2306 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2307 			if (err)
2308 				return (err);
2309 			vap->va_mode = old_va.va_mode & ~(S_ISUID | S_ISGID);
2310 		}
2311 	}
2312 	if (vap->va_mode != (mode_t)VNOVAL) {
2313 		/* Only root may set the sticky bit on non-directories */
2314 		if (checkperm && vp->v_type != VDIR && (vap->va_mode & S_ISTXT)
2315 		    && priv_check_cred(cred, PRIV_VFS_STICKYFILE))
2316 			return EFTYPE;
2317 		if (checkperm && (vap->va_mode & S_ISGID)) {
2318 			err = fuse_internal_getattr(vp, &old_va, cred, td);
2319 			if (err)
2320 				return (err);
2321 			if (!groupmember(old_va.va_gid, cred)) {
2322 				err = priv_check_cred(cred, PRIV_VFS_SETGID);
2323 				if (err)
2324 					return (err);
2325 			}
2326 		}
2327 		accmode |= VADMIN;
2328 	}
2329 
2330 	if (vfs_isrdonly(mp))
2331 		return EROFS;
2332 
2333 	if (checkperm) {
2334 		err = fuse_internal_access(vp, accmode, td, cred);
2335 	} else {
2336 		err = 0;
2337 	}
2338 	if (err)
2339 		return err;
2340 	else
2341 		return fuse_internal_setattr(vp, vap, td, cred);
2342 }
2343 
2344 /*
2345     struct vnop_strategy_args {
2346 	struct vnode *a_vp;
2347 	struct buf *a_bp;
2348     };
2349 */
2350 static int
2351 fuse_vnop_strategy(struct vop_strategy_args *ap)
2352 {
2353 	struct vnode *vp = ap->a_vp;
2354 	struct buf *bp = ap->a_bp;
2355 
2356 	if (!vp || fuse_isdeadfs(vp)) {
2357 		bp->b_ioflags |= BIO_ERROR;
2358 		bp->b_error = ENXIO;
2359 		bufdone(bp);
2360 		return 0;
2361 	}
2362 
2363 	/*
2364 	 * VOP_STRATEGY always returns zero and signals error via bp->b_ioflags.
2365 	 * fuse_io_strategy sets bp's error fields
2366 	 */
2367 	(void)fuse_io_strategy(vp, bp);
2368 
2369 	return 0;
2370 }
2371 
2372 /*
2373     struct vnop_symlink_args {
2374 	struct vnode *a_dvp;
2375 	struct vnode **a_vpp;
2376 	struct componentname *a_cnp;
2377 	struct vattr *a_vap;
2378 	char *a_target;
2379     };
2380 */
2381 static int
2382 fuse_vnop_symlink(struct vop_symlink_args *ap)
2383 {
2384 	struct vnode *dvp = ap->a_dvp;
2385 	struct vnode **vpp = ap->a_vpp;
2386 	struct componentname *cnp = ap->a_cnp;
2387 	const char *target = ap->a_target;
2388 
2389 	struct fuse_dispatcher fdi;
2390 
2391 	int err;
2392 	size_t len;
2393 
2394 	if (fuse_isdeadfs(dvp)) {
2395 		return ENXIO;
2396 	}
2397 	/*
2398 	 * Unlike the other creator type calls, here we have to create a message
2399 	 * where the name of the new entry comes first, and the data describing
2400 	 * the entry comes second.
2401 	 * Hence we can't rely on our handy fuse_internal_newentry() routine,
2402 	 * but put together the message manually and just call the core part.
2403 	 */
2404 
2405 	len = strlen(target) + 1;
2406 	fdisp_init(&fdi, len + cnp->cn_namelen + 1);
2407 	fdisp_make_vp(&fdi, FUSE_SYMLINK, dvp, curthread, NULL);
2408 
2409 	memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
2410 	((char *)fdi.indata)[cnp->cn_namelen] = '\0';
2411 	memcpy((char *)fdi.indata + cnp->cn_namelen + 1, target, len);
2412 
2413 	err = fuse_internal_newentry_core(dvp, vpp, cnp, VLNK, &fdi);
2414 	fdisp_destroy(&fdi);
2415 	return err;
2416 }
2417 
2418 /*
2419     struct vnop_write_args {
2420 	struct vnode *a_vp;
2421 	struct uio *a_uio;
2422 	int  a_ioflag;
2423 	struct ucred *a_cred;
2424     };
2425 */
2426 static int
2427 fuse_vnop_write(struct vop_write_args *ap)
2428 {
2429 	struct vnode *vp = ap->a_vp;
2430 	struct uio *uio = ap->a_uio;
2431 	int ioflag = ap->a_ioflag;
2432 	struct ucred *cred = ap->a_cred;
2433 	pid_t pid = curthread->td_proc->p_pid;
2434 	struct fuse_filehandle *fufh;
2435 	int err;
2436 	bool closefufh = false, directio;
2437 
2438 	MPASS(vp->v_type == VREG || vp->v_type == VDIR);
2439 
2440 	if (fuse_isdeadfs(vp)) {
2441 		return ENXIO;
2442 	}
2443 
2444 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
2445 		ioflag |= IO_DIRECT;
2446 	}
2447 
2448 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2449 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2450 		/*
2451 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2452 		 * must implicitly open the file here
2453 		 */
2454 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2455 		closefufh = true;
2456 	}
2457 	if (err) {
2458 		SDT_PROBE3(fusefs, , vnops, filehandles_closed, vp, uio, cred);
2459 		return err;
2460 	}
2461 
2462 	/*
2463          * Ideally, when the daemon asks for direct io at open time, the
2464          * standard file flag should be set according to this, so that would
2465          * just change the default mode, which later on could be changed via
2466          * fcntl(2).
2467          * But this doesn't work, the O_DIRECT flag gets cleared at some point
2468          * (don't know where). So to make any use of the Fuse direct_io option,
2469          * we hardwire it into the file's private data (similarly to Linux,
2470          * btw.).
2471          */
2472 	directio = (ioflag & IO_DIRECT) || !fsess_opt_datacache(vnode_mount(vp));
2473 
2474 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2475 	if (directio) {
2476 		off_t start, end, filesize;
2477 		bool pages = (ioflag & IO_VMIO) != 0;
2478 
2479 		SDT_PROBE2(fusefs, , vnops, trace, 1, "direct write of vnode");
2480 
2481 		err = fuse_vnode_size(vp, &filesize, cred, curthread);
2482 		if (err)
2483 			goto out;
2484 
2485 		start = uio->uio_offset;
2486 		end = start + uio->uio_resid;
2487 		if (!pages) {
2488 			err = fuse_inval_buf_range(vp, filesize, start,
2489 			    end);
2490 			if (err)
2491 				goto out;
2492 		}
2493 		err = fuse_write_directbackend(vp, uio, cred, fufh,
2494 			filesize, ioflag, pages);
2495 	} else {
2496 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2497 			"buffered write of vnode");
2498 		if (!fsess_opt_writeback(vnode_mount(vp)))
2499 			ioflag |= IO_SYNC;
2500 		err = fuse_write_biobackend(vp, uio, cred, fufh, ioflag, pid);
2501 	}
2502 	fuse_internal_clear_suid_on_write(vp, cred, uio->uio_td);
2503 
2504 out:
2505 	if (closefufh)
2506 		fuse_filehandle_close(vp, fufh, curthread, cred);
2507 
2508 	return (err);
2509 }
2510 
2511 static daddr_t
2512 fuse_gbp_getblkno(struct vnode *vp, vm_ooffset_t off)
2513 {
2514 	const int biosize = fuse_iosize(vp);
2515 
2516 	return (off / biosize);
2517 }
2518 
2519 static int
2520 fuse_gbp_getblksz(struct vnode *vp, daddr_t lbn, long *blksz)
2521 {
2522 	off_t filesize;
2523 	int err;
2524 	const int biosize = fuse_iosize(vp);
2525 
2526 	err = fuse_vnode_size(vp, &filesize, NULL, NULL);
2527 	if (err) {
2528 		/* This will turn into a SIGBUS */
2529 		return (EIO);
2530 	} else if ((off_t)lbn * biosize >= filesize) {
2531 		*blksz = 0;
2532 	} else if ((off_t)(lbn + 1) * biosize > filesize) {
2533 		*blksz = filesize - (off_t)lbn *biosize;
2534 	} else {
2535 		*blksz = biosize;
2536 	}
2537 	return (0);
2538 }
2539 
2540 /*
2541     struct vnop_getpages_args {
2542 	struct vnode *a_vp;
2543 	vm_page_t *a_m;
2544 	int a_count;
2545 	int a_reqpage;
2546     };
2547 */
2548 static int
2549 fuse_vnop_getpages(struct vop_getpages_args *ap)
2550 {
2551 	struct vnode *vp = ap->a_vp;
2552 
2553 	if (!fsess_opt_mmap(vnode_mount(vp))) {
2554 		SDT_PROBE2(fusefs, , vnops, trace, 1,
2555 			"called on non-cacheable vnode??\n");
2556 		return (VM_PAGER_ERROR);
2557 	}
2558 
2559 	return (vfs_bio_getpages(vp, ap->a_m, ap->a_count, ap->a_rbehind,
2560 	    ap->a_rahead, fuse_gbp_getblkno, fuse_gbp_getblksz));
2561 }
2562 
2563 static const char extattr_namespace_separator = '.';
2564 
2565 /*
2566     struct vop_getextattr_args {
2567 	struct vop_generic_args a_gen;
2568 	struct vnode *a_vp;
2569 	int a_attrnamespace;
2570 	const char *a_name;
2571 	struct uio *a_uio;
2572 	size_t *a_size;
2573 	struct ucred *a_cred;
2574 	struct thread *a_td;
2575     };
2576 */
2577 static int
2578 fuse_vnop_getextattr(struct vop_getextattr_args *ap)
2579 {
2580 	struct vnode *vp = ap->a_vp;
2581 	struct uio *uio = ap->a_uio;
2582 	struct fuse_dispatcher fdi;
2583 	struct fuse_getxattr_in *get_xattr_in;
2584 	struct fuse_getxattr_out *get_xattr_out;
2585 	struct mount *mp = vnode_mount(vp);
2586 	struct thread *td = ap->a_td;
2587 	struct ucred *cred = ap->a_cred;
2588 	char *prefix;
2589 	char *attr_str;
2590 	size_t len;
2591 	int err;
2592 
2593 	if (fuse_isdeadfs(vp))
2594 		return (ENXIO);
2595 
2596 	if (fsess_not_impl(mp, FUSE_GETXATTR))
2597 		return EOPNOTSUPP;
2598 
2599 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2600 	if (err)
2601 		return err;
2602 
2603 	/* Default to looking for user attributes. */
2604 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2605 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2606 	else
2607 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2608 
2609 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2610 	    strlen(ap->a_name) + 1;
2611 
2612 	fdisp_init(&fdi, len + sizeof(*get_xattr_in));
2613 	fdisp_make_vp(&fdi, FUSE_GETXATTR, vp, td, cred);
2614 
2615 	get_xattr_in = fdi.indata;
2616 	/*
2617 	 * Check to see whether we're querying the available size or
2618 	 * issuing the actual request.  If we pass in 0, we get back struct
2619 	 * fuse_getxattr_out.  If we pass in a non-zero size, we get back
2620 	 * that much data, without the struct fuse_getxattr_out header.
2621 	 */
2622 	if (uio == NULL)
2623 		get_xattr_in->size = 0;
2624 	else
2625 		get_xattr_in->size = uio->uio_resid;
2626 
2627 	attr_str = (char *)fdi.indata + sizeof(*get_xattr_in);
2628 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2629 	    ap->a_name);
2630 
2631 	err = fdisp_wait_answ(&fdi);
2632 	if (err != 0) {
2633 		if (err == ENOSYS) {
2634 			fsess_set_notimpl(mp, FUSE_GETXATTR);
2635 			err = EOPNOTSUPP;
2636 		}
2637 		goto out;
2638 	}
2639 
2640 	get_xattr_out = fdi.answ;
2641 
2642 	if (ap->a_size != NULL)
2643 		*ap->a_size = get_xattr_out->size;
2644 
2645 	if (uio != NULL)
2646 		err = uiomove(fdi.answ, fdi.iosize, uio);
2647 
2648 out:
2649 	fdisp_destroy(&fdi);
2650 	return (err);
2651 }
2652 
2653 /*
2654     struct vop_setextattr_args {
2655 	struct vop_generic_args a_gen;
2656 	struct vnode *a_vp;
2657 	int a_attrnamespace;
2658 	const char *a_name;
2659 	struct uio *a_uio;
2660 	struct ucred *a_cred;
2661 	struct thread *a_td;
2662     };
2663 */
2664 static int
2665 fuse_vnop_setextattr(struct vop_setextattr_args *ap)
2666 {
2667 	struct vnode *vp = ap->a_vp;
2668 	struct uio *uio = ap->a_uio;
2669 	struct fuse_dispatcher fdi;
2670 	struct fuse_setxattr_in *set_xattr_in;
2671 	struct mount *mp = vnode_mount(vp);
2672 	struct thread *td = ap->a_td;
2673 	struct ucred *cred = ap->a_cred;
2674 	char *prefix;
2675 	size_t len;
2676 	char *attr_str;
2677 	int err;
2678 
2679 	if (fuse_isdeadfs(vp))
2680 		return (ENXIO);
2681 
2682 	if (fsess_not_impl(mp, FUSE_SETXATTR))
2683 		return EOPNOTSUPP;
2684 
2685 	if (vfs_isrdonly(mp))
2686 		return EROFS;
2687 
2688 	/* Deleting xattrs must use VOP_DELETEEXTATTR instead */
2689 	if (ap->a_uio == NULL) {
2690 		/*
2691 		 * If we got here as fallback from VOP_DELETEEXTATTR, then
2692 		 * return EOPNOTSUPP.
2693 		 */
2694 		if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
2695 			return (EOPNOTSUPP);
2696 		else
2697 			return (EINVAL);
2698 	}
2699 
2700 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
2701 		VWRITE);
2702 	if (err)
2703 		return err;
2704 
2705 	/* Default to looking for user attributes. */
2706 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2707 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2708 	else
2709 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2710 
2711 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2712 	    strlen(ap->a_name) + 1;
2713 
2714 	fdisp_init(&fdi, len + sizeof(*set_xattr_in) + uio->uio_resid);
2715 	fdisp_make_vp(&fdi, FUSE_SETXATTR, vp, td, cred);
2716 
2717 	set_xattr_in = fdi.indata;
2718 	set_xattr_in->size = uio->uio_resid;
2719 
2720 	attr_str = (char *)fdi.indata + sizeof(*set_xattr_in);
2721 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2722 	    ap->a_name);
2723 
2724 	err = uiomove((char *)fdi.indata + sizeof(*set_xattr_in) + len,
2725 	    uio->uio_resid, uio);
2726 	if (err != 0) {
2727 		goto out;
2728 	}
2729 
2730 	err = fdisp_wait_answ(&fdi);
2731 
2732 	if (err == ENOSYS) {
2733 		fsess_set_notimpl(mp, FUSE_SETXATTR);
2734 		err = EOPNOTSUPP;
2735 	}
2736 	if (err == ERESTART) {
2737 		/* Can't restart after calling uiomove */
2738 		err = EINTR;
2739 	}
2740 
2741 out:
2742 	fdisp_destroy(&fdi);
2743 	return (err);
2744 }
2745 
2746 /*
2747  * The Linux / FUSE extended attribute list is simply a collection of
2748  * NUL-terminated strings.  The FreeBSD extended attribute list is a single
2749  * byte length followed by a non-NUL terminated string.  So, this allows
2750  * conversion of the Linux / FUSE format to the FreeBSD format in place.
2751  * Linux attribute names are reported with the namespace as a prefix (e.g.
2752  * "user.attribute_name"), but in FreeBSD they are reported without the
2753  * namespace prefix (e.g. "attribute_name").  So, we're going from:
2754  *
2755  * user.attr_name1\0user.attr_name2\0
2756  *
2757  * to:
2758  *
2759  * <num>attr_name1<num>attr_name2
2760  *
2761  * Where "<num>" is a single byte number of characters in the attribute name.
2762  *
2763  * Args:
2764  * prefix - exattr namespace prefix string
2765  * list, list_len - input list with namespace prefixes
2766  * bsd_list, bsd_list_len - output list compatible with bsd vfs
2767  */
2768 static int
2769 fuse_xattrlist_convert(char *prefix, const char *list, int list_len,
2770     char *bsd_list, int *bsd_list_len)
2771 {
2772 	int len, pos, dist_to_next, prefix_len;
2773 
2774 	pos = 0;
2775 	*bsd_list_len = 0;
2776 	prefix_len = strlen(prefix);
2777 
2778 	while (pos < list_len && list[pos] != '\0') {
2779 		dist_to_next = strlen(&list[pos]) + 1;
2780 		if (bcmp(&list[pos], prefix, prefix_len) == 0 &&
2781 		    list[pos + prefix_len] == extattr_namespace_separator) {
2782 			len = dist_to_next -
2783 			    (prefix_len + sizeof(extattr_namespace_separator)) - 1;
2784 			if (len >= EXTATTR_MAXNAMELEN)
2785 				return (ENAMETOOLONG);
2786 
2787 			bsd_list[*bsd_list_len] = len;
2788 			memcpy(&bsd_list[*bsd_list_len + 1],
2789 			    &list[pos + prefix_len +
2790 			    sizeof(extattr_namespace_separator)], len);
2791 
2792 			*bsd_list_len += len + 1;
2793 		}
2794 
2795 		pos += dist_to_next;
2796 	}
2797 
2798 	return (0);
2799 }
2800 
2801 /*
2802  * List extended attributes
2803  *
2804  * The FUSE_LISTXATTR operation is based on Linux's listxattr(2) syscall, which
2805  * has a number of differences compared to its FreeBSD equivalent,
2806  * extattr_list_file:
2807  *
2808  * - FUSE_LISTXATTR returns all extended attributes across all namespaces,
2809  *   whereas listxattr(2) only returns attributes for a single namespace
2810  * - FUSE_LISTXATTR prepends each attribute name with "namespace."
2811  * - If the provided buffer is not large enough to hold the result,
2812  *   FUSE_LISTXATTR should return ERANGE, whereas listxattr is expected to
2813  *   return as many results as will fit.
2814  */
2815 /*
2816     struct vop_listextattr_args {
2817 	struct vop_generic_args a_gen;
2818 	struct vnode *a_vp;
2819 	int a_attrnamespace;
2820 	struct uio *a_uio;
2821 	size_t *a_size;
2822 	struct ucred *a_cred;
2823 	struct thread *a_td;
2824     };
2825 */
2826 static int
2827 fuse_vnop_listextattr(struct vop_listextattr_args *ap)
2828 {
2829 	struct vnode *vp = ap->a_vp;
2830 	struct uio *uio = ap->a_uio;
2831 	struct fuse_dispatcher fdi;
2832 	struct fuse_listxattr_in *list_xattr_in;
2833 	struct fuse_listxattr_out *list_xattr_out;
2834 	struct mount *mp = vnode_mount(vp);
2835 	struct thread *td = ap->a_td;
2836 	struct ucred *cred = ap->a_cred;
2837 	char *prefix;
2838 	char *bsd_list = NULL;
2839 	char *linux_list;
2840 	int bsd_list_len;
2841 	int linux_list_len;
2842 	int err;
2843 
2844 	if (fuse_isdeadfs(vp))
2845 		return (ENXIO);
2846 
2847 	if (fsess_not_impl(mp, FUSE_LISTXATTR))
2848 		return EOPNOTSUPP;
2849 
2850 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2851 	if (err)
2852 		return err;
2853 
2854 	/*
2855 	 * Add space for a NUL and the period separator if enabled.
2856 	 * Default to looking for user attributes.
2857 	 */
2858 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2859 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2860 	else
2861 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2862 
2863 	fdisp_init(&fdi, sizeof(*list_xattr_in));
2864 	fdisp_make_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2865 
2866 	/*
2867 	 * Retrieve Linux / FUSE compatible list size.
2868 	 */
2869 	list_xattr_in = fdi.indata;
2870 	list_xattr_in->size = 0;
2871 
2872 	err = fdisp_wait_answ(&fdi);
2873 	if (err != 0) {
2874 		if (err == ENOSYS) {
2875 			fsess_set_notimpl(mp, FUSE_LISTXATTR);
2876 			err = EOPNOTSUPP;
2877 		}
2878 		goto out;
2879 	}
2880 
2881 	list_xattr_out = fdi.answ;
2882 	linux_list_len = list_xattr_out->size;
2883 	if (linux_list_len == 0) {
2884 		if (ap->a_size != NULL)
2885 			*ap->a_size = linux_list_len;
2886 		goto out;
2887 	}
2888 
2889 	/*
2890 	 * Retrieve Linux / FUSE compatible list values.
2891 	 */
2892 	fdisp_refresh_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2893 	list_xattr_in = fdi.indata;
2894 	list_xattr_in->size = linux_list_len;
2895 
2896 	err = fdisp_wait_answ(&fdi);
2897 	if (err == ERANGE) {
2898 		/*
2899 		 * Race detected.  The attribute list must've grown since the
2900 		 * first FUSE_LISTXATTR call.  Start over.  Go all the way back
2901 		 * to userland so we can process signals, if necessary, before
2902 		 * restarting.
2903 		 */
2904 		err = ERESTART;
2905 		goto out;
2906 	} else if (err != 0)
2907 		goto out;
2908 
2909 	linux_list = fdi.answ;
2910 	/* FUSE doesn't allow the server to return more data than requested */
2911 	if (fdi.iosize > linux_list_len) {
2912 		struct fuse_data *data = fuse_get_mpdata(mp);
2913 
2914 		fuse_warn(data, FSESS_WARN_LSEXTATTR_LONG,
2915 			"server returned "
2916 			"more extended attribute data than requested; "
2917 			"should've returned ERANGE instead.");
2918 	} else {
2919 		/* But returning less data is fine */
2920 		linux_list_len = fdi.iosize;
2921 	}
2922 
2923 	/*
2924 	 * Retrieve the BSD compatible list values.
2925 	 * The Linux / FUSE attribute list format isn't the same
2926 	 * as FreeBSD's format. So we need to transform it into
2927 	 * FreeBSD's format before giving it to the user.
2928 	 */
2929 	bsd_list = malloc(linux_list_len, M_TEMP, M_WAITOK);
2930 	err = fuse_xattrlist_convert(prefix, linux_list, linux_list_len,
2931 	    bsd_list, &bsd_list_len);
2932 	if (err != 0)
2933 		goto out;
2934 
2935 	if (ap->a_size != NULL)
2936 		*ap->a_size = bsd_list_len;
2937 
2938 	if (uio != NULL)
2939 		err = uiomove(bsd_list, bsd_list_len, uio);
2940 
2941 out:
2942 	free(bsd_list, M_TEMP);
2943 	fdisp_destroy(&fdi);
2944 	return (err);
2945 }
2946 
2947 /*
2948     struct vop_deallocate_args {
2949 	struct vop_generic_args a_gen;
2950 	struct vnode *a_vp;
2951 	off_t *a_offset;
2952 	off_t *a_len;
2953 	int a_flags;
2954 	int a_ioflag;
2955         struct ucred *a_cred;
2956     };
2957 */
2958 static int
2959 fuse_vnop_deallocate(struct vop_deallocate_args *ap)
2960 {
2961 	struct vnode *vp = ap->a_vp;
2962 	struct mount *mp = vnode_mount(vp);
2963 	struct fuse_filehandle *fufh;
2964 	struct fuse_dispatcher fdi;
2965 	struct fuse_fallocate_in *ffi;
2966 	struct ucred *cred = ap->a_cred;
2967 	pid_t pid = curthread->td_proc->p_pid;
2968 	off_t *len = ap->a_len;
2969 	off_t *offset = ap->a_offset;
2970 	int ioflag = ap->a_ioflag;
2971 	off_t filesize;
2972 	int err;
2973 	bool closefufh = false;
2974 
2975 	if (fuse_isdeadfs(vp))
2976 		return (ENXIO);
2977 
2978 	if (vfs_isrdonly(mp))
2979 		return (EROFS);
2980 
2981 	if (fsess_not_impl(mp, FUSE_FALLOCATE))
2982 		goto fallback;
2983 
2984 	err = fuse_filehandle_getrw(vp, FWRITE, &fufh, cred, pid);
2985 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
2986 		/*
2987 		 * nfsd will do I/O without first doing VOP_OPEN.  We
2988 		 * must implicitly open the file here
2989 		 */
2990 		err = fuse_filehandle_open(vp, FWRITE, &fufh, curthread, cred);
2991 		closefufh = true;
2992 	}
2993 	if (err)
2994 		return (err);
2995 
2996 	fuse_vnode_update(vp, FN_MTIMECHANGE | FN_CTIMECHANGE);
2997 
2998 	err = fuse_vnode_size(vp, &filesize, cred, curthread);
2999 	if (err)
3000 		goto out;
3001 	fuse_inval_buf_range(vp, filesize, *offset, *offset + *len);
3002 
3003 	fdisp_init(&fdi, sizeof(*ffi));
3004 	fdisp_make_vp(&fdi, FUSE_FALLOCATE, vp, curthread, cred);
3005 	ffi = fdi.indata;
3006 	ffi->fh = fufh->fh_id;
3007 	ffi->offset = *offset;
3008 	ffi->length = *len;
3009 	/*
3010 	 * FreeBSD's fspacectl is equivalent to Linux's fallocate with
3011 	 * mode == FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE
3012 	 */
3013 	ffi->mode = FUSE_FALLOC_FL_PUNCH_HOLE | FUSE_FALLOC_FL_KEEP_SIZE;
3014 	err = fdisp_wait_answ(&fdi);
3015 
3016 	if (err == ENOSYS) {
3017 		fdisp_destroy(&fdi);
3018 		fsess_set_notimpl(mp, FUSE_FALLOCATE);
3019 		goto fallback;
3020 	} else if (err == EOPNOTSUPP) {
3021 		/*
3022 		 * The file system server does not support FUSE_FALLOCATE with
3023 		 * the supplied mode for this particular file.
3024 		 */
3025 		fdisp_destroy(&fdi);
3026 		goto fallback;
3027 	} else if (!err) {
3028 		/*
3029 		 * Clip the returned offset to EoF.  Do it here rather than
3030 		 * before FUSE_FALLOCATE just in case the kernel's cached file
3031 		 * size is out of date.  Unfortunately, FUSE does not return
3032 		 * any information about filesize from that operation.
3033 		 */
3034 		*offset = MIN(*offset + *len, filesize);
3035 		*len = 0;
3036 		fuse_vnode_undirty_cached_timestamps(vp, false);
3037 		fuse_internal_clear_suid_on_write(vp, cred, curthread);
3038 
3039 		if (ioflag & IO_SYNC)
3040 			err = fuse_internal_fsync(vp, curthread, MNT_WAIT,
3041 			    false);
3042 	}
3043 
3044 out:
3045 	fdisp_destroy(&fdi);
3046 	if (closefufh)
3047 		fuse_filehandle_close(vp, fufh, curthread, cred);
3048 
3049 	return (err);
3050 
3051 fallback:
3052 	if (closefufh)
3053 		fuse_filehandle_close(vp, fufh, curthread, cred);
3054 
3055 	return (vop_stddeallocate(ap));
3056 }
3057 
3058 /*
3059     struct vop_deleteextattr_args {
3060 	struct vop_generic_args a_gen;
3061 	struct vnode *a_vp;
3062 	int a_attrnamespace;
3063 	const char *a_name;
3064 	struct ucred *a_cred;
3065 	struct thread *a_td;
3066     };
3067 */
3068 static int
3069 fuse_vnop_deleteextattr(struct vop_deleteextattr_args *ap)
3070 {
3071 	struct vnode *vp = ap->a_vp;
3072 	struct fuse_dispatcher fdi;
3073 	struct mount *mp = vnode_mount(vp);
3074 	struct thread *td = ap->a_td;
3075 	struct ucred *cred = ap->a_cred;
3076 	char *prefix;
3077 	size_t len;
3078 	char *attr_str;
3079 	int err;
3080 
3081 	if (fuse_isdeadfs(vp))
3082 		return (ENXIO);
3083 
3084 	if (fsess_not_impl(mp, FUSE_REMOVEXATTR))
3085 		return EOPNOTSUPP;
3086 
3087 	if (vfs_isrdonly(mp))
3088 		return EROFS;
3089 
3090 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
3091 		VWRITE);
3092 	if (err)
3093 		return err;
3094 
3095 	/* Default to looking for user attributes. */
3096 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
3097 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
3098 	else
3099 		prefix = EXTATTR_NAMESPACE_USER_STRING;
3100 
3101 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
3102 	    strlen(ap->a_name) + 1;
3103 
3104 	fdisp_init(&fdi, len);
3105 	fdisp_make_vp(&fdi, FUSE_REMOVEXATTR, vp, td, cred);
3106 
3107 	attr_str = fdi.indata;
3108 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
3109 	    ap->a_name);
3110 
3111 	err = fdisp_wait_answ(&fdi);
3112 	if (err == ENOSYS) {
3113 		fsess_set_notimpl(mp, FUSE_REMOVEXATTR);
3114 		err = EOPNOTSUPP;
3115 	}
3116 
3117 	fdisp_destroy(&fdi);
3118 	return (err);
3119 }
3120 
3121 /*
3122     struct vnop_print_args {
3123 	struct vnode *a_vp;
3124     };
3125 */
3126 static int
3127 fuse_vnop_print(struct vop_print_args *ap)
3128 {
3129 	struct fuse_vnode_data *fvdat = VTOFUD(ap->a_vp);
3130 
3131 	printf("nodeid: %ju, parent nodeid: %ju, nlookup: %ju, flag: %#x\n",
3132 	    (uintmax_t)VTOILLU(ap->a_vp), (uintmax_t)fvdat->parent_nid,
3133 	    (uintmax_t)fvdat->nlookup,
3134 	    fvdat->flag);
3135 
3136 	return 0;
3137 }
3138 
3139 /*
3140  * Get an NFS filehandle for a FUSE file.
3141  *
3142  * This will only work for FUSE file systems that guarantee the uniqueness of
3143  * nodeid:generation, which most don't.
3144  */
3145 /*
3146 vop_vptofh {
3147 	IN struct vnode *a_vp;
3148 	IN struct fid *a_fhp;
3149 };
3150 */
3151 static int
3152 fuse_vnop_vptofh(struct vop_vptofh_args *ap)
3153 {
3154 	struct vnode *vp = ap->a_vp;
3155 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
3156 	struct fuse_fid *fhp = (struct fuse_fid *)(ap->a_fhp);
3157 	_Static_assert(sizeof(struct fuse_fid) <= sizeof(struct fid),
3158 		"FUSE fid type is too big");
3159 	struct mount *mp = vnode_mount(vp);
3160 	struct fuse_data *data = fuse_get_mpdata(mp);
3161 	struct vattr va;
3162 	int err;
3163 
3164 	if (!(data->dataflags & FSESS_EXPORT_SUPPORT)) {
3165 		/* NFS requires lookups for "." and ".." */
3166 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3167 			"VOP_VPTOFH without FUSE_EXPORT_SUPPORT");
3168 		return EOPNOTSUPP;
3169 	}
3170 	if ((mp->mnt_flag & MNT_EXPORTED) &&
3171 		!(data->dataflags & FSESS_NO_OPENDIR_SUPPORT))
3172 	{
3173 		/*
3174 		 * NFS is stateless, so nfsd must reopen a directory on every
3175 		 * call to VOP_READDIR, passing in the d_off field from the
3176 		 * final dirent of the previous invocation.  But without
3177 		 * FUSE_NO_OPENDIR_SUPPORT, the FUSE protocol does not
3178 		 * guarantee that d_off will be valid after a directory is
3179 		 * closed and reopened.  So prohibit exporting FUSE file
3180 		 * systems that don't set that flag.
3181 		 *
3182 		 * But userspace NFS servers don't have this problem.
3183                  */
3184 		SDT_PROBE2(fusefs, , vnops, trace, 1,
3185 			"VOP_VPTOFH without FUSE_NO_OPENDIR_SUPPORT");
3186 		return EOPNOTSUPP;
3187 	}
3188 
3189 	err = fuse_internal_getattr(vp, &va, curthread->td_ucred, curthread);
3190 	if (err)
3191 		return err;
3192 
3193 	/*ip = VTOI(ap->a_vp);*/
3194 	/*ufhp = (struct ufid *)ap->a_fhp;*/
3195 	fhp->len = sizeof(struct fuse_fid);
3196 	fhp->nid = fvdat->nid;
3197 	if (fvdat->generation <= UINT32_MAX)
3198 		fhp->gen = fvdat->generation;
3199 	else
3200 		return EOVERFLOW;
3201 	return (0);
3202 }
3203