xref: /freebsd/sys/fs/fuse/fuse_vnops.c (revision 53071ed1c96db7f89defc99c95b0ad1031d48f45)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2007-2009 Google Inc. and Amit Singh
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are
9  * met:
10  *
11  * * Redistributions of source code must retain the above copyright
12  *   notice, this list of conditions and the following disclaimer.
13  * * Redistributions in binary form must reproduce the above
14  *   copyright notice, this list of conditions and the following disclaimer
15  *   in the documentation and/or other materials provided with the
16  *   distribution.
17  * * Neither the name of Google Inc. nor the names of its
18  *   contributors may be used to endorse or promote products derived from
19  *   this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  * Copyright (C) 2005 Csaba Henk.
34  * All rights reserved.
35  *
36  * Copyright (c) 2019 The FreeBSD Foundation
37  *
38  * Portions of this software were developed by BFF Storage Systems, LLC under
39  * sponsorship from the FreeBSD Foundation.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  *
50  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  */
62 
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD$");
65 
66 #include <sys/param.h>
67 #include <sys/module.h>
68 #include <sys/systm.h>
69 #include <sys/errno.h>
70 #include <sys/kernel.h>
71 #include <sys/conf.h>
72 #include <sys/uio.h>
73 #include <sys/malloc.h>
74 #include <sys/queue.h>
75 #include <sys/limits.h>
76 #include <sys/lock.h>
77 #include <sys/rwlock.h>
78 #include <sys/sx.h>
79 #include <sys/proc.h>
80 #include <sys/mount.h>
81 #include <sys/vnode.h>
82 #include <sys/namei.h>
83 #include <sys/extattr.h>
84 #include <sys/stat.h>
85 #include <sys/unistd.h>
86 #include <sys/filedesc.h>
87 #include <sys/file.h>
88 #include <sys/fcntl.h>
89 #include <sys/dirent.h>
90 #include <sys/bio.h>
91 #include <sys/buf.h>
92 #include <sys/sysctl.h>
93 #include <sys/vmmeter.h>
94 
95 #include <vm/vm.h>
96 #include <vm/vm_extern.h>
97 #include <vm/pmap.h>
98 #include <vm/vm_map.h>
99 #include <vm/vm_page.h>
100 #include <vm/vm_param.h>
101 #include <vm/vm_object.h>
102 #include <vm/vm_pager.h>
103 #include <vm/vnode_pager.h>
104 #include <vm/vm_object.h>
105 
106 #include "fuse.h"
107 #include "fuse_file.h"
108 #include "fuse_internal.h"
109 #include "fuse_ipc.h"
110 #include "fuse_node.h"
111 #include "fuse_io.h"
112 
113 #include <sys/priv.h>
114 
115 /* Maximum number of hardlinks to a single FUSE file */
116 #define FUSE_LINK_MAX                      UINT32_MAX
117 
118 SDT_PROVIDER_DECLARE(fusefs);
119 /*
120  * Fuse trace probe:
121  * arg0: verbosity.  Higher numbers give more verbose messages
122  * arg1: Textual message
123  */
124 SDT_PROBE_DEFINE2(fusefs, , vnops, trace, "int", "char*");
125 
126 /* vnode ops */
127 static vop_access_t fuse_vnop_access;
128 static vop_advlock_t fuse_vnop_advlock;
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_create_t fuse_vnop_create;
133 static vop_deleteextattr_t fuse_vnop_deleteextattr;
134 static vop_fdatasync_t fuse_vnop_fdatasync;
135 static vop_fsync_t fuse_vnop_fsync;
136 static vop_getattr_t fuse_vnop_getattr;
137 static vop_getextattr_t fuse_vnop_getextattr;
138 static vop_inactive_t fuse_vnop_inactive;
139 static vop_link_t fuse_vnop_link;
140 static vop_listextattr_t fuse_vnop_listextattr;
141 static vop_lookup_t fuse_vnop_lookup;
142 static vop_mkdir_t fuse_vnop_mkdir;
143 static vop_mknod_t fuse_vnop_mknod;
144 static vop_open_t fuse_vnop_open;
145 static vop_pathconf_t fuse_vnop_pathconf;
146 static vop_read_t fuse_vnop_read;
147 static vop_readdir_t fuse_vnop_readdir;
148 static vop_readlink_t fuse_vnop_readlink;
149 static vop_reclaim_t fuse_vnop_reclaim;
150 static vop_remove_t fuse_vnop_remove;
151 static vop_rename_t fuse_vnop_rename;
152 static vop_rmdir_t fuse_vnop_rmdir;
153 static vop_setattr_t fuse_vnop_setattr;
154 static vop_setextattr_t fuse_vnop_setextattr;
155 static vop_strategy_t fuse_vnop_strategy;
156 static vop_symlink_t fuse_vnop_symlink;
157 static vop_write_t fuse_vnop_write;
158 static vop_getpages_t fuse_vnop_getpages;
159 static vop_print_t fuse_vnop_print;
160 static vop_vptofh_t fuse_vnop_vptofh;
161 
162 struct vop_vector fuse_fifoops = {
163 	.vop_default =		&fifo_specops,
164 	.vop_access =		fuse_vnop_access,
165 	.vop_close =		fuse_fifo_close,
166 	.vop_fsync =		fuse_vnop_fsync,
167 	.vop_getattr =		fuse_vnop_getattr,
168 	.vop_inactive =		fuse_vnop_inactive,
169 	.vop_pathconf =		fuse_vnop_pathconf,
170 	.vop_print =		fuse_vnop_print,
171 	.vop_read =		VOP_PANIC,
172 	.vop_reclaim =		fuse_vnop_reclaim,
173 	.vop_setattr =		fuse_vnop_setattr,
174 	.vop_write =		VOP_PANIC,
175 	.vop_vptofh =		fuse_vnop_vptofh,
176 };
177 VFS_VOP_VECTOR_REGISTER(fuse_fifoops);
178 
179 struct vop_vector fuse_vnops = {
180 	.vop_allocate =	VOP_EINVAL,
181 	.vop_default = &default_vnodeops,
182 	.vop_access = fuse_vnop_access,
183 	.vop_advlock = fuse_vnop_advlock,
184 	.vop_bmap = fuse_vnop_bmap,
185 	.vop_close = fuse_vnop_close,
186 	.vop_create = fuse_vnop_create,
187 	.vop_deleteextattr = fuse_vnop_deleteextattr,
188 	.vop_fsync = fuse_vnop_fsync,
189 	.vop_fdatasync = fuse_vnop_fdatasync,
190 	.vop_getattr = fuse_vnop_getattr,
191 	.vop_getextattr = fuse_vnop_getextattr,
192 	.vop_inactive = fuse_vnop_inactive,
193 	/*
194 	 * TODO: implement vop_ioctl after upgrading to protocol 7.16.
195 	 * FUSE_IOCTL was added in 7.11, but 32-bit compat is broken until
196 	 * 7.16.
197 	 */
198 	.vop_link = fuse_vnop_link,
199 	.vop_listextattr = fuse_vnop_listextattr,
200 	.vop_lookup = fuse_vnop_lookup,
201 	.vop_mkdir = fuse_vnop_mkdir,
202 	.vop_mknod = fuse_vnop_mknod,
203 	.vop_open = fuse_vnop_open,
204 	.vop_pathconf = fuse_vnop_pathconf,
205 	/*
206 	 * TODO: implement vop_poll after upgrading to protocol 7.21.
207 	 * FUSE_POLL was added in protocol 7.11, but it's kind of broken until
208 	 * 7.21, which adds the ability for the client to choose which poll
209 	 * events it wants, and for a client to deregister a file handle
210 	 */
211 	.vop_read = fuse_vnop_read,
212 	.vop_readdir = fuse_vnop_readdir,
213 	.vop_readlink = fuse_vnop_readlink,
214 	.vop_reclaim = fuse_vnop_reclaim,
215 	.vop_remove = fuse_vnop_remove,
216 	.vop_rename = fuse_vnop_rename,
217 	.vop_rmdir = fuse_vnop_rmdir,
218 	.vop_setattr = fuse_vnop_setattr,
219 	.vop_setextattr = fuse_vnop_setextattr,
220 	.vop_strategy = fuse_vnop_strategy,
221 	.vop_symlink = fuse_vnop_symlink,
222 	.vop_write = fuse_vnop_write,
223 	.vop_getpages = fuse_vnop_getpages,
224 	.vop_print = fuse_vnop_print,
225 	.vop_vptofh = fuse_vnop_vptofh,
226 };
227 VFS_VOP_VECTOR_REGISTER(fuse_vnops);
228 
229 uma_zone_t fuse_pbuf_zone;
230 
231 /* Check permission for extattr operations, much like extattr_check_cred */
232 static int
233 fuse_extattr_check_cred(struct vnode *vp, int ns, struct ucred *cred,
234 	struct thread *td, accmode_t accmode)
235 {
236 	struct mount *mp = vnode_mount(vp);
237 	struct fuse_data *data = fuse_get_mpdata(mp);
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 (data->dataflags & FSESS_DEFAULT_PERMISSIONS) {
252 			return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM));
253 		}
254 		/* FALLTHROUGH */
255 	case EXTATTR_NAMESPACE_USER:
256 		return (fuse_internal_access(vp, accmode, td, cred));
257 	default:
258 		return (EPERM);
259 	}
260 }
261 
262 /* Get a filehandle for a directory */
263 static int
264 fuse_filehandle_get_dir(struct vnode *vp, struct fuse_filehandle **fufhp,
265 	struct ucred *cred, pid_t pid)
266 {
267 	if (fuse_filehandle_get(vp, FREAD, fufhp, cred, pid) == 0)
268 		return 0;
269 	return fuse_filehandle_get(vp, FEXEC, fufhp, cred, pid);
270 }
271 
272 /* Send FUSE_FLUSH for this vnode */
273 static int
274 fuse_flush(struct vnode *vp, struct ucred *cred, pid_t pid, int fflag)
275 {
276 	struct fuse_flush_in *ffi;
277 	struct fuse_filehandle *fufh;
278 	struct fuse_dispatcher fdi;
279 	struct thread *td = curthread;
280 	struct mount *mp = vnode_mount(vp);
281 	int err;
282 
283 	if (!fsess_isimpl(vnode_mount(vp), FUSE_FLUSH))
284 		return 0;
285 
286 	err = fuse_filehandle_getrw(vp, fflag, &fufh, cred, pid);
287 	if (err)
288 		return err;
289 
290 	fdisp_init(&fdi, sizeof(*ffi));
291 	fdisp_make_vp(&fdi, FUSE_FLUSH, vp, td, cred);
292 	ffi = fdi.indata;
293 	ffi->fh = fufh->fh_id;
294 	/*
295 	 * If the file has a POSIX lock then we're supposed to set lock_owner.
296 	 * If not, then lock_owner is undefined.  So we may as well always set
297 	 * it.
298 	 */
299 	ffi->lock_owner = td->td_proc->p_pid;
300 
301 	err = fdisp_wait_answ(&fdi);
302 	if (err == ENOSYS) {
303 		fsess_set_notimpl(mp, FUSE_FLUSH);
304 		err = 0;
305 	}
306 	fdisp_destroy(&fdi);
307 	return err;
308 }
309 
310 /* Close wrapper for fifos.  */
311 static int
312 fuse_fifo_close(struct vop_close_args *ap)
313 {
314 	return (fifo_specops.vop_close(ap));
315 }
316 
317 /*
318     struct vnop_access_args {
319 	struct vnode *a_vp;
320 #if VOP_ACCESS_TAKES_ACCMODE_T
321 	accmode_t a_accmode;
322 #else
323 	int a_mode;
324 #endif
325 	struct ucred *a_cred;
326 	struct thread *a_td;
327     };
328 */
329 static int
330 fuse_vnop_access(struct vop_access_args *ap)
331 {
332 	struct vnode *vp = ap->a_vp;
333 	int accmode = ap->a_accmode;
334 	struct ucred *cred = ap->a_cred;
335 
336 	struct fuse_data *data = fuse_get_mpdata(vnode_mount(vp));
337 
338 	int err;
339 
340 	if (fuse_isdeadfs(vp)) {
341 		if (vnode_isvroot(vp)) {
342 			return 0;
343 		}
344 		return ENXIO;
345 	}
346 	if (!(data->dataflags & FSESS_INITED)) {
347 		if (vnode_isvroot(vp)) {
348 			if (priv_check_cred(cred, PRIV_VFS_ADMIN) ||
349 			    (fuse_match_cred(data->daemoncred, cred) == 0)) {
350 				return 0;
351 			}
352 		}
353 		return EBADF;
354 	}
355 	if (vnode_islnk(vp)) {
356 		return 0;
357 	}
358 
359 	err = fuse_internal_access(vp, accmode, ap->a_td, ap->a_cred);
360 	return err;
361 }
362 
363 /*
364  * struct vop_advlock_args {
365  *	struct vop_generic_args a_gen;
366  *	struct vnode *a_vp;
367  *	void *a_id;
368  *	int a_op;
369  *	struct flock *a_fl;
370  *	int a_flags;
371  * }
372  */
373 static int
374 fuse_vnop_advlock(struct vop_advlock_args *ap)
375 {
376 	struct vnode *vp = ap->a_vp;
377 	struct flock *fl = ap->a_fl;
378 	struct thread *td = curthread;
379 	struct ucred *cred = td->td_ucred;
380 	pid_t pid = td->td_proc->p_pid;
381 	struct fuse_filehandle *fufh;
382 	struct fuse_dispatcher fdi;
383 	struct fuse_lk_in *fli;
384 	struct fuse_lk_out *flo;
385 	enum fuse_opcode op;
386 	int dataflags, err;
387 	int flags = ap->a_flags;
388 
389 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
390 
391 	if (fuse_isdeadfs(vp)) {
392 		return ENXIO;
393 	}
394 
395 	if (!(dataflags & FSESS_POSIX_LOCKS))
396 		return vop_stdadvlock(ap);
397 	/* FUSE doesn't properly support flock until protocol 7.17 */
398 	if (flags & F_FLOCK)
399 		return vop_stdadvlock(ap);
400 
401 	err = fuse_filehandle_get_anyflags(vp, &fufh, cred, pid);
402 	if (err)
403 		return err;
404 
405 	fdisp_init(&fdi, sizeof(*fli));
406 
407 	switch(ap->a_op) {
408 	case F_GETLK:
409 		op = FUSE_GETLK;
410 		break;
411 	case F_SETLK:
412 		op = FUSE_SETLK;
413 		break;
414 	case F_SETLKW:
415 		op = FUSE_SETLKW;
416 		break;
417 	default:
418 		return EINVAL;
419 	}
420 
421 	fdisp_make_vp(&fdi, op, vp, td, cred);
422 	fli = fdi.indata;
423 	fli->fh = fufh->fh_id;
424 	fli->owner = fl->l_pid;
425 	fli->lk.start = fl->l_start;
426 	if (fl->l_len != 0)
427 		fli->lk.end = fl->l_start + fl->l_len - 1;
428 	else
429 		fli->lk.end = INT64_MAX;
430 	fli->lk.type = fl->l_type;
431 	fli->lk.pid = fl->l_pid;
432 
433 	err = fdisp_wait_answ(&fdi);
434 	fdisp_destroy(&fdi);
435 
436 	if (err == 0 && op == FUSE_GETLK) {
437 		flo = fdi.answ;
438 		fl->l_type = flo->lk.type;
439 		fl->l_pid = flo->lk.pid;
440 		if (flo->lk.type != F_UNLCK) {
441 			fl->l_start = flo->lk.start;
442 			if (flo->lk.end == INT64_MAX)
443 				fl->l_len = 0;
444 			else
445 				fl->l_len = flo->lk.end - flo->lk.start + 1;
446 			fl->l_start = flo->lk.start;
447 		}
448 	}
449 
450 	return err;
451 }
452 
453 /* {
454 	struct vnode *a_vp;
455 	daddr_t a_bn;
456 	struct bufobj **a_bop;
457 	daddr_t *a_bnp;
458 	int *a_runp;
459 	int *a_runb;
460 } */
461 static int
462 fuse_vnop_bmap(struct vop_bmap_args *ap)
463 {
464 	struct vnode *vp = ap->a_vp;
465 	struct bufobj **bo = ap->a_bop;
466 	struct thread *td = curthread;
467 	struct mount *mp;
468 	struct fuse_dispatcher fdi;
469 	struct fuse_bmap_in *fbi;
470 	struct fuse_bmap_out *fbo;
471 	struct fuse_data *data;
472 	uint64_t biosize;
473 	off_t filesize;
474 	daddr_t lbn = ap->a_bn;
475 	daddr_t *pbn = ap->a_bnp;
476 	int *runp = ap->a_runp;
477 	int *runb = ap->a_runb;
478 	int error = 0;
479 	int maxrun;
480 
481 	if (fuse_isdeadfs(vp)) {
482 		return ENXIO;
483 	}
484 
485 	mp = vnode_mount(vp);
486 	data = fuse_get_mpdata(mp);
487 	biosize = fuse_iosize(vp);
488 	maxrun = MIN(vp->v_mount->mnt_iosize_max / biosize - 1,
489 		data->max_readahead_blocks);
490 
491 	if (bo != NULL)
492 		*bo = &vp->v_bufobj;
493 
494 	/*
495 	 * The FUSE_BMAP operation does not include the runp and runb
496 	 * variables, so we must guess.  Report nonzero contiguous runs so
497 	 * cluster_read will combine adjacent reads.  It's worthwhile to reduce
498 	 * upcalls even if we don't know the true physical layout of the file.
499 	 *
500 	 * FUSE file systems may opt out of read clustering in two ways:
501 	 * * mounting with -onoclusterr
502 	 * * Setting max_readahead <= maxbcachebuf during FUSE_INIT
503 	 */
504 	if (runb != NULL)
505 		*runb = MIN(lbn, maxrun);
506 	if (runp != NULL) {
507 		error = fuse_vnode_size(vp, &filesize, td->td_ucred, td);
508 		if (error == 0)
509 			*runp = MIN(MAX(0, filesize / (off_t)biosize - lbn - 1),
510 				    maxrun);
511 		else
512 			*runp = 0;
513 	}
514 
515 	if (fsess_isimpl(mp, FUSE_BMAP)) {
516 		fdisp_init(&fdi, sizeof(*fbi));
517 		fdisp_make_vp(&fdi, FUSE_BMAP, vp, td, td->td_ucred);
518 		fbi = fdi.indata;
519 		fbi->block = lbn;
520 		fbi->blocksize = biosize;
521 		error = fdisp_wait_answ(&fdi);
522 		if (error == ENOSYS) {
523 			fdisp_destroy(&fdi);
524 			fsess_set_notimpl(mp, FUSE_BMAP);
525 			error = 0;
526 		} else {
527 			fbo = fdi.answ;
528 			if (error == 0 && pbn != NULL)
529 				*pbn = fbo->block;
530 			fdisp_destroy(&fdi);
531 			return error;
532 		}
533 	}
534 
535 	/* If the daemon doesn't support BMAP, make up a sensible default */
536 	if (pbn != NULL)
537 		*pbn = lbn * btodb(biosize);
538 	return (error);
539 }
540 
541 /*
542     struct vop_close_args {
543 	struct vnode *a_vp;
544 	int  a_fflag;
545 	struct ucred *a_cred;
546 	struct thread *a_td;
547     };
548 */
549 static int
550 fuse_vnop_close(struct vop_close_args *ap)
551 {
552 	struct vnode *vp = ap->a_vp;
553 	struct ucred *cred = ap->a_cred;
554 	int fflag = ap->a_fflag;
555 	struct thread *td = ap->a_td;
556 	pid_t pid = td->td_proc->p_pid;
557 	int err = 0;
558 
559 	if (fuse_isdeadfs(vp))
560 		return 0;
561 	if (vnode_isdir(vp))
562 		return 0;
563 	if (fflag & IO_NDELAY)
564 		return 0;
565 
566 	err = fuse_flush(vp, cred, pid, fflag);
567 	/* TODO: close the file handle, if we're sure it's no longer used */
568 	if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) {
569 		fuse_vnode_savesize(vp, cred, td->td_proc->p_pid);
570 	}
571 	return err;
572 }
573 
574 static void
575 fdisp_make_mknod_for_fallback(
576 	struct fuse_dispatcher *fdip,
577 	struct componentname *cnp,
578 	struct vnode *dvp,
579 	uint64_t parentnid,
580 	struct thread *td,
581 	struct ucred *cred,
582 	mode_t mode,
583 	enum fuse_opcode *op)
584 {
585 	struct fuse_mknod_in *fmni;
586 
587 	fdisp_init(fdip, sizeof(*fmni) + cnp->cn_namelen + 1);
588 	*op = FUSE_MKNOD;
589 	fdisp_make(fdip, *op, vnode_mount(dvp), parentnid, td, cred);
590 	fmni = fdip->indata;
591 	fmni->mode = mode;
592 	fmni->rdev = 0;
593 	memcpy((char *)fdip->indata + sizeof(*fmni), cnp->cn_nameptr,
594 	    cnp->cn_namelen);
595 	((char *)fdip->indata)[sizeof(*fmni) + cnp->cn_namelen] = '\0';
596 }
597 /*
598     struct vnop_create_args {
599 	struct vnode *a_dvp;
600 	struct vnode **a_vpp;
601 	struct componentname *a_cnp;
602 	struct vattr *a_vap;
603     };
604 */
605 static int
606 fuse_vnop_create(struct vop_create_args *ap)
607 {
608 	struct vnode *dvp = ap->a_dvp;
609 	struct vnode **vpp = ap->a_vpp;
610 	struct componentname *cnp = ap->a_cnp;
611 	struct vattr *vap = ap->a_vap;
612 	struct thread *td = cnp->cn_thread;
613 	struct ucred *cred = cnp->cn_cred;
614 
615 	struct fuse_data *data;
616 	struct fuse_create_in *fci;
617 	struct fuse_entry_out *feo;
618 	struct fuse_open_out *foo;
619 	struct fuse_dispatcher fdi, fdi2;
620 	struct fuse_dispatcher *fdip = &fdi;
621 	struct fuse_dispatcher *fdip2 = NULL;
622 
623 	int err;
624 
625 	struct mount *mp = vnode_mount(dvp);
626 	data = fuse_get_mpdata(mp);
627 	uint64_t parentnid = VTOFUD(dvp)->nid;
628 	mode_t mode = MAKEIMODE(vap->va_type, vap->va_mode);
629 	enum fuse_opcode op;
630 	int flags;
631 
632 	if (fuse_isdeadfs(dvp))
633 		return ENXIO;
634 
635 	/* FUSE expects sockets to be created with FUSE_MKNOD */
636 	if (vap->va_type == VSOCK)
637 		return fuse_internal_mknod(dvp, vpp, cnp, vap);
638 
639 	/*
640 	 * VOP_CREATE doesn't tell us the open(2) flags, so we guess.  Only a
641 	 * writable mode makes sense, and we might as well include readability
642 	 * too.
643 	 */
644 	flags = O_RDWR;
645 
646 	bzero(&fdi, sizeof(fdi));
647 
648 	if (vap->va_type != VREG)
649 		return (EINVAL);
650 
651 	if (!fsess_isimpl(mp, FUSE_CREATE) || vap->va_type == VSOCK) {
652 		/* Fallback to FUSE_MKNOD/FUSE_OPEN */
653 		fdisp_make_mknod_for_fallback(fdip, cnp, dvp, parentnid, td,
654 			cred, mode, &op);
655 	} else {
656 		/* Use FUSE_CREATE */
657 		size_t insize;
658 
659 		op = FUSE_CREATE;
660 		fdisp_init(fdip, sizeof(*fci) + cnp->cn_namelen + 1);
661 		fdisp_make(fdip, op, vnode_mount(dvp), parentnid, td, cred);
662 		fci = fdip->indata;
663 		fci->mode = mode;
664 		fci->flags = O_CREAT | flags;
665 		if (fuse_libabi_geq(data, 7, 12)) {
666 			insize = sizeof(*fci);
667 			fci->umask = td->td_proc->p_fd->fd_cmask;
668 		} else {
669 			insize = sizeof(struct fuse_open_in);
670 		}
671 
672 		memcpy((char *)fdip->indata + insize, cnp->cn_nameptr,
673 		    cnp->cn_namelen);
674 		((char *)fdip->indata)[insize + cnp->cn_namelen] = '\0';
675 	}
676 
677 	err = fdisp_wait_answ(fdip);
678 
679 	if (err) {
680 		if (err == ENOSYS && op == FUSE_CREATE) {
681 			fsess_set_notimpl(mp, FUSE_CREATE);
682 			fdisp_destroy(fdip);
683 			fdisp_make_mknod_for_fallback(fdip, cnp, dvp,
684 				parentnid, td, cred, mode, &op);
685 			err = fdisp_wait_answ(fdip);
686 		}
687 		if (err)
688 			goto out;
689 	}
690 
691 	feo = fdip->answ;
692 
693 	if ((err = fuse_internal_checkentry(feo, vap->va_type))) {
694 		goto out;
695 	}
696 
697 	if (op == FUSE_CREATE) {
698 		foo = (struct fuse_open_out*)(feo + 1);
699 	} else {
700 		/* Issue a separate FUSE_OPEN */
701 		struct fuse_open_in *foi;
702 
703 		fdip2 = &fdi2;
704 		fdisp_init(fdip2, sizeof(*foi));
705 		fdisp_make(fdip2, FUSE_OPEN, vnode_mount(dvp), feo->nodeid, td,
706 			cred);
707 		foi = fdip2->indata;
708 		foi->flags = flags;
709 		err = fdisp_wait_answ(fdip2);
710 		if (err)
711 			goto out;
712 		foo = fdip2->answ;
713 	}
714 	err = fuse_vnode_get(mp, feo, feo->nodeid, dvp, vpp, cnp, vap->va_type);
715 	if (err) {
716 		struct fuse_release_in *fri;
717 		uint64_t nodeid = feo->nodeid;
718 		uint64_t fh_id = foo->fh;
719 
720 		fdisp_init(fdip, sizeof(*fri));
721 		fdisp_make(fdip, FUSE_RELEASE, mp, nodeid, td, cred);
722 		fri = fdip->indata;
723 		fri->fh = fh_id;
724 		fri->flags = flags;
725 		fuse_insert_callback(fdip->tick, fuse_internal_forget_callback);
726 		fuse_insert_message(fdip->tick, false);
727 		goto out;
728 	}
729 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnop_create");
730 	fuse_internal_cache_attrs(*vpp, &feo->attr, feo->attr_valid,
731 		feo->attr_valid_nsec, NULL);
732 
733 	fuse_filehandle_init(*vpp, FUFH_RDWR, NULL, td, cred, foo);
734 	fuse_vnode_open(*vpp, foo->open_flags, td);
735 	/*
736 	 * Purge the parent's attribute cache because the daemon should've
737 	 * updated its mtime and ctime
738 	 */
739 	fuse_vnode_clear_attr_cache(dvp);
740 	cache_purge_negative(dvp);
741 
742 out:
743 	if (fdip2)
744 		fdisp_destroy(fdip2);
745 	fdisp_destroy(fdip);
746 	return err;
747 }
748 
749 /*
750     struct vnop_fdatasync_args {
751 	struct vop_generic_args a_gen;
752 	struct vnode * a_vp;
753 	struct thread * a_td;
754     };
755 */
756 static int
757 fuse_vnop_fdatasync(struct vop_fdatasync_args *ap)
758 {
759 	struct vnode *vp = ap->a_vp;
760 	struct thread *td = ap->a_td;
761 	int waitfor = MNT_WAIT;
762 
763 	int err = 0;
764 
765 	if (fuse_isdeadfs(vp)) {
766 		return 0;
767 	}
768 	if ((err = vop_stdfdatasync_buf(ap)))
769 		return err;
770 
771 	return fuse_internal_fsync(vp, td, waitfor, true);
772 }
773 
774 /*
775     struct vnop_fsync_args {
776 	struct vop_generic_args a_gen;
777 	struct vnode * a_vp;
778 	int  a_waitfor;
779 	struct thread * a_td;
780     };
781 */
782 static int
783 fuse_vnop_fsync(struct vop_fsync_args *ap)
784 {
785 	struct vnode *vp = ap->a_vp;
786 	struct thread *td = ap->a_td;
787 	int waitfor = ap->a_waitfor;
788 	int err = 0;
789 
790 	if (fuse_isdeadfs(vp)) {
791 		return 0;
792 	}
793 	if ((err = vop_stdfsync(ap)))
794 		return err;
795 
796 	return fuse_internal_fsync(vp, td, waitfor, false);
797 }
798 
799 /*
800     struct vnop_getattr_args {
801 	struct vnode *a_vp;
802 	struct vattr *a_vap;
803 	struct ucred *a_cred;
804 	struct thread *a_td;
805     };
806 */
807 static int
808 fuse_vnop_getattr(struct vop_getattr_args *ap)
809 {
810 	struct vnode *vp = ap->a_vp;
811 	struct vattr *vap = ap->a_vap;
812 	struct ucred *cred = ap->a_cred;
813 	struct thread *td = curthread;
814 
815 	int err = 0;
816 	int dataflags;
817 
818 	dataflags = fuse_get_mpdata(vnode_mount(vp))->dataflags;
819 
820 	/* Note that we are not bailing out on a dead file system just yet. */
821 
822 	if (!(dataflags & FSESS_INITED)) {
823 		if (!vnode_isvroot(vp)) {
824 			fdata_set_dead(fuse_get_mpdata(vnode_mount(vp)));
825 			err = ENOTCONN;
826 			return err;
827 		} else {
828 			goto fake;
829 		}
830 	}
831 	err = fuse_internal_getattr(vp, vap, cred, td);
832 	if (err == ENOTCONN && vnode_isvroot(vp)) {
833 		/* see comment in fuse_vfsop_statfs() */
834 		goto fake;
835 	} else {
836 		return err;
837 	}
838 
839 fake:
840 	bzero(vap, sizeof(*vap));
841 	vap->va_type = vnode_vtype(vp);
842 
843 	return 0;
844 }
845 
846 /*
847     struct vnop_inactive_args {
848 	struct vnode *a_vp;
849 	struct thread *a_td;
850     };
851 */
852 static int
853 fuse_vnop_inactive(struct vop_inactive_args *ap)
854 {
855 	struct vnode *vp = ap->a_vp;
856 	struct thread *td = ap->a_td;
857 
858 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
859 	struct fuse_filehandle *fufh, *fufh_tmp;
860 
861 	int need_flush = 1;
862 
863 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
864 		if (need_flush && vp->v_type == VREG) {
865 			if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) {
866 				fuse_vnode_savesize(vp, NULL, 0);
867 			}
868 			if ((fvdat->flag & FN_REVOKED) != 0)
869 				fuse_io_invalbuf(vp, td);
870 			else
871 				fuse_io_flushbuf(vp, MNT_WAIT, td);
872 			need_flush = 0;
873 		}
874 		fuse_filehandle_close(vp, fufh, td, NULL);
875 	}
876 
877 	if ((fvdat->flag & FN_REVOKED) != 0)
878 		vrecycle(vp);
879 
880 	return 0;
881 }
882 
883 /*
884     struct vnop_link_args {
885 	struct vnode *a_tdvp;
886 	struct vnode *a_vp;
887 	struct componentname *a_cnp;
888     };
889 */
890 static int
891 fuse_vnop_link(struct vop_link_args *ap)
892 {
893 	struct vnode *vp = ap->a_vp;
894 	struct vnode *tdvp = ap->a_tdvp;
895 	struct componentname *cnp = ap->a_cnp;
896 
897 	struct vattr *vap = VTOVA(vp);
898 
899 	struct fuse_dispatcher fdi;
900 	struct fuse_entry_out *feo;
901 	struct fuse_link_in fli;
902 
903 	int err;
904 
905 	if (fuse_isdeadfs(vp)) {
906 		return ENXIO;
907 	}
908 	if (vnode_mount(tdvp) != vnode_mount(vp)) {
909 		return EXDEV;
910 	}
911 
912 	/*
913 	 * This is a seatbelt check to protect naive userspace filesystems from
914 	 * themselves and the limitations of the FUSE IPC protocol.  If a
915 	 * filesystem does not allow attribute caching, assume it is capable of
916 	 * validating that nlink does not overflow.
917 	 */
918 	if (vap != NULL && vap->va_nlink >= FUSE_LINK_MAX)
919 		return EMLINK;
920 	fli.oldnodeid = VTOI(vp);
921 
922 	fdisp_init(&fdi, 0);
923 	fuse_internal_newentry_makerequest(vnode_mount(tdvp), VTOI(tdvp), cnp,
924 	    FUSE_LINK, &fli, sizeof(fli), &fdi);
925 	if ((err = fdisp_wait_answ(&fdi))) {
926 		goto out;
927 	}
928 	feo = fdi.answ;
929 
930 	err = fuse_internal_checkentry(feo, vnode_vtype(vp));
931 	if (!err) {
932 		/*
933 		 * Purge the parent's attribute cache because the daemon
934 		 * should've updated its mtime and ctime
935 		 */
936 		fuse_vnode_clear_attr_cache(tdvp);
937 		fuse_internal_cache_attrs(vp, &feo->attr, feo->attr_valid,
938 			feo->attr_valid_nsec, NULL);
939 	}
940 out:
941 	fdisp_destroy(&fdi);
942 	return err;
943 }
944 
945 struct fuse_lookup_alloc_arg {
946 	struct fuse_entry_out *feo;
947 	struct componentname *cnp;
948 	uint64_t nid;
949 	enum vtype vtyp;
950 };
951 
952 /* Callback for vn_get_ino */
953 static int
954 fuse_lookup_alloc(struct mount *mp, void *arg, int lkflags, struct vnode **vpp)
955 {
956 	struct fuse_lookup_alloc_arg *flaa = arg;
957 
958 	return fuse_vnode_get(mp, flaa->feo, flaa->nid, NULL, vpp, flaa->cnp,
959 		flaa->vtyp);
960 }
961 
962 SDT_PROBE_DEFINE3(fusefs, , vnops, cache_lookup,
963 	"int", "struct timespec*", "struct timespec*");
964 /*
965     struct vnop_lookup_args {
966 	struct vnodeop_desc *a_desc;
967 	struct vnode *a_dvp;
968 	struct vnode **a_vpp;
969 	struct componentname *a_cnp;
970     };
971 */
972 int
973 fuse_vnop_lookup(struct vop_lookup_args *ap)
974 {
975 	struct vnode *dvp = ap->a_dvp;
976 	struct vnode **vpp = ap->a_vpp;
977 	struct componentname *cnp = ap->a_cnp;
978 	struct thread *td = cnp->cn_thread;
979 	struct ucred *cred = cnp->cn_cred;
980 
981 	int nameiop = cnp->cn_nameiop;
982 	int flags = cnp->cn_flags;
983 	int wantparent = flags & (LOCKPARENT | WANTPARENT);
984 	int islastcn = flags & ISLASTCN;
985 	struct mount *mp = vnode_mount(dvp);
986 
987 	int err = 0;
988 	int lookup_err = 0;
989 	struct vnode *vp = NULL;
990 
991 	struct fuse_dispatcher fdi;
992 	bool did_lookup = false;
993 	struct fuse_entry_out *feo = NULL;
994 	enum vtype vtyp;	/* vnode type of target */
995 	off_t filesize;		/* filesize of target */
996 
997 	uint64_t nid;
998 
999 	if (fuse_isdeadfs(dvp)) {
1000 		*vpp = NULL;
1001 		return ENXIO;
1002 	}
1003 	if (!vnode_isdir(dvp))
1004 		return ENOTDIR;
1005 
1006 	if (islastcn && vfs_isrdonly(mp) && (nameiop != LOOKUP))
1007 		return EROFS;
1008 
1009 	if ((cnp->cn_flags & NOEXECCHECK) != 0)
1010 		cnp->cn_flags &= ~NOEXECCHECK;
1011 	else if ((err = fuse_internal_access(dvp, VEXEC, td, cred)))
1012 		return err;
1013 
1014 	if (flags & ISDOTDOT) {
1015 		KASSERT(VTOFUD(dvp)->flag & FN_PARENT_NID,
1016 			("Looking up .. is TODO"));
1017 		nid = VTOFUD(dvp)->parent_nid;
1018 		if (nid == 0)
1019 			return ENOENT;
1020 		/* .. is obviously a directory */
1021 		vtyp = VDIR;
1022 		filesize = 0;
1023 	} else if (cnp->cn_namelen == 1 && *(cnp->cn_nameptr) == '.') {
1024 		nid = VTOI(dvp);
1025 		/* . is obviously a directory */
1026 		vtyp = VDIR;
1027 		filesize = 0;
1028 	} else {
1029 		struct timespec now, timeout;
1030 
1031 		err = cache_lookup(dvp, vpp, cnp, &timeout, NULL);
1032 		getnanouptime(&now);
1033 		SDT_PROBE3(fusefs, , vnops, cache_lookup, err, &timeout, &now);
1034 		switch (err) {
1035 		case -1:		/* positive match */
1036 			if (timespeccmp(&timeout, &now, >)) {
1037 				counter_u64_add(fuse_lookup_cache_hits, 1);
1038 			} else {
1039 				/* Cache timeout */
1040 				counter_u64_add(fuse_lookup_cache_misses, 1);
1041 				bintime_clear(
1042 					&VTOFUD(*vpp)->entry_cache_timeout);
1043 				cache_purge(*vpp);
1044 				if (dvp != *vpp)
1045 					vput(*vpp);
1046 				else
1047 					vrele(*vpp);
1048 				*vpp = NULL;
1049 				break;
1050 			}
1051 			return 0;
1052 
1053 		case 0:		/* no match in cache */
1054 			counter_u64_add(fuse_lookup_cache_misses, 1);
1055 			break;
1056 
1057 		case ENOENT:		/* negative match */
1058 			getnanouptime(&now);
1059 			if (timespeccmp(&timeout, &now, <=)) {
1060 				/* Cache timeout */
1061 				cache_purge_negative(dvp);
1062 				break;
1063 			}
1064 			/* fall through */
1065 		default:
1066 			return err;
1067 		}
1068 
1069 		nid = VTOI(dvp);
1070 		fdisp_init(&fdi, cnp->cn_namelen + 1);
1071 		fdisp_make(&fdi, FUSE_LOOKUP, mp, nid, td, cred);
1072 
1073 		memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
1074 		((char *)fdi.indata)[cnp->cn_namelen] = '\0';
1075 		lookup_err = fdisp_wait_answ(&fdi);
1076 		did_lookup = true;
1077 
1078 		if (!lookup_err) {
1079 			/* lookup call succeeded */
1080 			feo = (struct fuse_entry_out *)fdi.answ;
1081 			nid = feo->nodeid;
1082 			if (nid == 0) {
1083 				/* zero nodeid means ENOENT and cache it */
1084 				struct timespec timeout;
1085 
1086 				fdi.answ_stat = ENOENT;
1087 				lookup_err = ENOENT;
1088 				if (cnp->cn_flags & MAKEENTRY) {
1089 					fuse_validity_2_timespec(feo, &timeout);
1090 					cache_enter_time(dvp, *vpp, cnp,
1091 						&timeout, NULL);
1092 				}
1093 			} else if (nid == FUSE_ROOT_ID) {
1094 				lookup_err = EINVAL;
1095 			}
1096 			vtyp = IFTOVT(feo->attr.mode);
1097 			filesize = feo->attr.size;
1098 		}
1099 		if (lookup_err && (!fdi.answ_stat || lookup_err != ENOENT)) {
1100 			fdisp_destroy(&fdi);
1101 			return lookup_err;
1102 		}
1103 	}
1104 	/* lookup_err, if non-zero, must be ENOENT at this point */
1105 
1106 	if (lookup_err) {
1107 		/* Entry not found */
1108 		if ((nameiop == CREATE || nameiop == RENAME) && islastcn) {
1109 			err = fuse_internal_access(dvp, VWRITE, td, cred);
1110 			if (!err) {
1111 				/*
1112 				 * Set the SAVENAME flag to hold onto the
1113 				 * pathname for use later in VOP_CREATE or
1114 				 * VOP_RENAME.
1115 				 */
1116 				cnp->cn_flags |= SAVENAME;
1117 
1118 				err = EJUSTRETURN;
1119 			}
1120 		} else {
1121 			err = ENOENT;
1122 		}
1123 	} else {
1124 		/* Entry was found */
1125 		if (flags & ISDOTDOT) {
1126 			struct fuse_lookup_alloc_arg flaa;
1127 
1128 			flaa.nid = nid;
1129 			flaa.feo = feo;
1130 			flaa.cnp = cnp;
1131 			flaa.vtyp = vtyp;
1132 			err = vn_vget_ino_gen(dvp, fuse_lookup_alloc, &flaa, 0,
1133 				&vp);
1134 			*vpp = vp;
1135 		} else if (nid == VTOI(dvp)) {
1136 			vref(dvp);
1137 			*vpp = dvp;
1138 		} else {
1139 			struct fuse_vnode_data *fvdat;
1140 
1141 			err = fuse_vnode_get(vnode_mount(dvp), feo, nid, dvp,
1142 			    &vp, cnp, vtyp);
1143 			if (err)
1144 				goto out;
1145 			*vpp = vp;
1146 
1147 			/*
1148 			 * In the case where we are looking up a FUSE node
1149 			 * represented by an existing cached vnode, and the
1150 			 * true size reported by FUSE_LOOKUP doesn't match
1151 			 * the vnode's cached size, then any cached writes
1152 			 * beyond the file's current size are lost.
1153 			 *
1154 			 * We can get here:
1155 			 * * following attribute cache expiration, or
1156 			 * * due a bug in the daemon, or
1157 			 */
1158 			fvdat = VTOFUD(vp);
1159 			if (vnode_isreg(vp) &&
1160 			    filesize != fvdat->cached_attrs.va_size &&
1161 			    fvdat->flag & FN_SIZECHANGE) {
1162 				/*
1163 				 * The FN_SIZECHANGE flag reflects a dirty
1164 				 * append.  If userspace lets us know our cache
1165 				 * is invalid, that write was lost.  (Dirty
1166 				 * writes that do not cause append are also
1167 				 * lost, but we don't detect them here.)
1168 				 *
1169 				 * XXX: Maybe disable WB caching on this mount.
1170 				 */
1171 				printf("%s: WB cache incoherent on %s!\n",
1172 				    __func__,
1173 				    vnode_mount(vp)->mnt_stat.f_mntonname);
1174 
1175 				fvdat->flag &= ~FN_SIZECHANGE;
1176 			}
1177 
1178 			MPASS(feo != NULL);
1179 			fuse_internal_cache_attrs(*vpp, &feo->attr,
1180 				feo->attr_valid, feo->attr_valid_nsec, NULL);
1181 			fuse_validity_2_bintime(feo->entry_valid,
1182 				feo->entry_valid_nsec,
1183 				&fvdat->entry_cache_timeout);
1184 
1185 			if ((nameiop == DELETE || nameiop == RENAME) &&
1186 				islastcn)
1187 			{
1188 				struct vattr dvattr;
1189 
1190 				err = fuse_internal_access(dvp, VWRITE, td,
1191 					cred);
1192 				if (err != 0)
1193 					goto out;
1194 				/*
1195 				 * if the parent's sticky bit is set, check
1196 				 * whether we're allowed to remove the file.
1197 				 * Need to figure out the vnode locking to make
1198 				 * this work.
1199 				 */
1200 				fuse_internal_getattr(dvp, &dvattr, cred, td);
1201 				if ((dvattr.va_mode & S_ISTXT) &&
1202 					fuse_internal_access(dvp, VADMIN, td,
1203 						cred) &&
1204 					fuse_internal_access(*vpp, VADMIN, td,
1205 						cred)) {
1206 					err = EPERM;
1207 					goto out;
1208 				}
1209 			}
1210 
1211 			if (islastcn && (
1212 				(nameiop == DELETE) ||
1213 				(nameiop == RENAME && wantparent))) {
1214 				cnp->cn_flags |= SAVENAME;
1215 			}
1216 
1217 		}
1218 	}
1219 out:
1220 	if (err) {
1221 		if (vp != NULL && dvp != vp)
1222 			vput(vp);
1223 		else if (vp != NULL)
1224 			vrele(vp);
1225 		*vpp = NULL;
1226 	}
1227 	if (did_lookup)
1228 		fdisp_destroy(&fdi);
1229 
1230 	return err;
1231 }
1232 
1233 /*
1234     struct vnop_mkdir_args {
1235 	struct vnode *a_dvp;
1236 	struct vnode **a_vpp;
1237 	struct componentname *a_cnp;
1238 	struct vattr *a_vap;
1239     };
1240 */
1241 static int
1242 fuse_vnop_mkdir(struct vop_mkdir_args *ap)
1243 {
1244 	struct vnode *dvp = ap->a_dvp;
1245 	struct vnode **vpp = ap->a_vpp;
1246 	struct componentname *cnp = ap->a_cnp;
1247 	struct vattr *vap = ap->a_vap;
1248 
1249 	struct fuse_mkdir_in fmdi;
1250 
1251 	if (fuse_isdeadfs(dvp)) {
1252 		return ENXIO;
1253 	}
1254 	fmdi.mode = MAKEIMODE(vap->va_type, vap->va_mode);
1255 	fmdi.umask = curthread->td_proc->p_fd->fd_cmask;
1256 
1257 	return (fuse_internal_newentry(dvp, vpp, cnp, FUSE_MKDIR, &fmdi,
1258 	    sizeof(fmdi), VDIR));
1259 }
1260 
1261 /*
1262     struct vnop_mknod_args {
1263 	struct vnode *a_dvp;
1264 	struct vnode **a_vpp;
1265 	struct componentname *a_cnp;
1266 	struct vattr *a_vap;
1267     };
1268 */
1269 static int
1270 fuse_vnop_mknod(struct vop_mknod_args *ap)
1271 {
1272 
1273 	struct vnode *dvp = ap->a_dvp;
1274 	struct vnode **vpp = ap->a_vpp;
1275 	struct componentname *cnp = ap->a_cnp;
1276 	struct vattr *vap = ap->a_vap;
1277 
1278 	if (fuse_isdeadfs(dvp))
1279 		return ENXIO;
1280 
1281 	return fuse_internal_mknod(dvp, vpp, cnp, vap);
1282 }
1283 
1284 /*
1285     struct vop_open_args {
1286 	struct vnode *a_vp;
1287 	int  a_mode;
1288 	struct ucred *a_cred;
1289 	struct thread *a_td;
1290 	int a_fdidx; / struct file *a_fp;
1291     };
1292 */
1293 static int
1294 fuse_vnop_open(struct vop_open_args *ap)
1295 {
1296 	struct vnode *vp = ap->a_vp;
1297 	int a_mode = ap->a_mode;
1298 	struct thread *td = ap->a_td;
1299 	struct ucred *cred = ap->a_cred;
1300 	pid_t pid = td->td_proc->p_pid;
1301 	struct fuse_vnode_data *fvdat;
1302 
1303 	if (fuse_isdeadfs(vp))
1304 		return ENXIO;
1305 	if (vp->v_type == VCHR || vp->v_type == VBLK || vp->v_type == VFIFO)
1306 		return (EOPNOTSUPP);
1307 	if ((a_mode & (FREAD | FWRITE | FEXEC)) == 0)
1308 		return EINVAL;
1309 
1310 	fvdat = VTOFUD(vp);
1311 
1312 	if (fuse_filehandle_validrw(vp, a_mode, cred, pid)) {
1313 		fuse_vnode_open(vp, 0, td);
1314 		return 0;
1315 	}
1316 
1317 	return fuse_filehandle_open(vp, a_mode, NULL, td, cred);
1318 }
1319 
1320 static int
1321 fuse_vnop_pathconf(struct vop_pathconf_args *ap)
1322 {
1323 
1324 	switch (ap->a_name) {
1325 	case _PC_FILESIZEBITS:
1326 		*ap->a_retval = 64;
1327 		return (0);
1328 	case _PC_NAME_MAX:
1329 		*ap->a_retval = NAME_MAX;
1330 		return (0);
1331 	case _PC_LINK_MAX:
1332 		*ap->a_retval = MIN(LONG_MAX, FUSE_LINK_MAX);
1333 		return (0);
1334 	case _PC_SYMLINK_MAX:
1335 		*ap->a_retval = MAXPATHLEN;
1336 		return (0);
1337 	case _PC_NO_TRUNC:
1338 		*ap->a_retval = 1;
1339 		return (0);
1340 	default:
1341 		return (vop_stdpathconf(ap));
1342 	}
1343 }
1344 
1345 /*
1346     struct vnop_read_args {
1347 	struct vnode *a_vp;
1348 	struct uio *a_uio;
1349 	int  a_ioflag;
1350 	struct ucred *a_cred;
1351     };
1352 */
1353 static int
1354 fuse_vnop_read(struct vop_read_args *ap)
1355 {
1356 	struct vnode *vp = ap->a_vp;
1357 	struct uio *uio = ap->a_uio;
1358 	int ioflag = ap->a_ioflag;
1359 	struct ucred *cred = ap->a_cred;
1360 	pid_t pid = curthread->td_proc->p_pid;
1361 
1362 	if (fuse_isdeadfs(vp)) {
1363 		return ENXIO;
1364 	}
1365 
1366 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
1367 		ioflag |= IO_DIRECT;
1368 	}
1369 
1370 	return fuse_io_dispatch(vp, uio, ioflag, cred, pid);
1371 }
1372 
1373 /*
1374     struct vnop_readdir_args {
1375 	struct vnode *a_vp;
1376 	struct uio *a_uio;
1377 	struct ucred *a_cred;
1378 	int *a_eofflag;
1379 	int *a_ncookies;
1380 	u_long **a_cookies;
1381     };
1382 */
1383 static int
1384 fuse_vnop_readdir(struct vop_readdir_args *ap)
1385 {
1386 	struct vnode *vp = ap->a_vp;
1387 	struct uio *uio = ap->a_uio;
1388 	struct ucred *cred = ap->a_cred;
1389 	struct fuse_filehandle *fufh = NULL;
1390 	struct fuse_iov cookediov;
1391 	int err = 0;
1392 	u_long *cookies;
1393 	off_t startoff;
1394 	ssize_t tresid;
1395 	int ncookies;
1396 	bool closefufh = false;
1397 	pid_t pid = curthread->td_proc->p_pid;
1398 
1399 	if (ap->a_eofflag)
1400 		*ap->a_eofflag = 0;
1401 	if (fuse_isdeadfs(vp)) {
1402 		return ENXIO;
1403 	}
1404 	if (				/* XXXIP ((uio_iovcnt(uio) > 1)) || */
1405 	    (uio_resid(uio) < sizeof(struct dirent))) {
1406 		return EINVAL;
1407 	}
1408 
1409 	tresid = uio->uio_resid;
1410 	startoff = uio->uio_offset;
1411 	err = fuse_filehandle_get_dir(vp, &fufh, cred, pid);
1412 	if (err == EBADF && vnode_mount(vp)->mnt_flag & MNT_EXPORTED) {
1413 		/*
1414 		 * nfsd will do VOP_READDIR without first doing VOP_OPEN.  We
1415 		 * must implicitly open the directory here
1416 		 */
1417 		err = fuse_filehandle_open(vp, FREAD, &fufh, curthread, cred);
1418 		if (err == 0) {
1419 			/*
1420 			 * When a directory is opened, it must be read from
1421 			 * the beginning.  Hopefully, the "startoff" still
1422 			 * exists as an offset cookie for the directory.
1423 			 * If not, it will read the entire directory without
1424 			 * returning any entries and just return eof.
1425 			 */
1426 			uio->uio_offset = 0;
1427 		}
1428 		closefufh = true;
1429 	}
1430 	if (err)
1431 		return (err);
1432 	if (ap->a_ncookies != NULL) {
1433 		ncookies = uio->uio_resid /
1434 			(offsetof(struct dirent, d_name) + 4) + 1;
1435 		cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK);
1436 		*ap->a_ncookies = ncookies;
1437 		*ap->a_cookies = cookies;
1438 	} else {
1439 		ncookies = 0;
1440 		cookies = NULL;
1441 	}
1442 #define DIRCOOKEDSIZE FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + MAXNAMLEN + 1)
1443 	fiov_init(&cookediov, DIRCOOKEDSIZE);
1444 
1445 	err = fuse_internal_readdir(vp, uio, startoff, fufh, &cookediov,
1446 		&ncookies, cookies);
1447 
1448 	fiov_teardown(&cookediov);
1449 	if (closefufh)
1450 		fuse_filehandle_close(vp, fufh, curthread, cred);
1451 
1452 	if (ap->a_ncookies != NULL) {
1453 		if (err == 0) {
1454 			*ap->a_ncookies -= ncookies;
1455 		} else {
1456 			free(*ap->a_cookies, M_TEMP);
1457 			*ap->a_ncookies = 0;
1458 			*ap->a_cookies = NULL;
1459 		}
1460 	}
1461 	if (err == 0 && tresid == uio->uio_resid)
1462 		*ap->a_eofflag = 1;
1463 
1464 	return err;
1465 }
1466 
1467 /*
1468     struct vnop_readlink_args {
1469 	struct vnode *a_vp;
1470 	struct uio *a_uio;
1471 	struct ucred *a_cred;
1472     };
1473 */
1474 static int
1475 fuse_vnop_readlink(struct vop_readlink_args *ap)
1476 {
1477 	struct vnode *vp = ap->a_vp;
1478 	struct uio *uio = ap->a_uio;
1479 	struct ucred *cred = ap->a_cred;
1480 
1481 	struct fuse_dispatcher fdi;
1482 	int err;
1483 
1484 	if (fuse_isdeadfs(vp)) {
1485 		return ENXIO;
1486 	}
1487 	if (!vnode_islnk(vp)) {
1488 		return EINVAL;
1489 	}
1490 	fdisp_init(&fdi, 0);
1491 	err = fdisp_simple_putget_vp(&fdi, FUSE_READLINK, vp, curthread, cred);
1492 	if (err) {
1493 		goto out;
1494 	}
1495 	if (((char *)fdi.answ)[0] == '/' &&
1496 	    fuse_get_mpdata(vnode_mount(vp))->dataflags & FSESS_PUSH_SYMLINKS_IN) {
1497 		char *mpth = vnode_mount(vp)->mnt_stat.f_mntonname;
1498 
1499 		err = uiomove(mpth, strlen(mpth), uio);
1500 	}
1501 	if (!err) {
1502 		err = uiomove(fdi.answ, fdi.iosize, uio);
1503 	}
1504 out:
1505 	fdisp_destroy(&fdi);
1506 	return err;
1507 }
1508 
1509 /*
1510     struct vnop_reclaim_args {
1511 	struct vnode *a_vp;
1512 	struct thread *a_td;
1513     };
1514 */
1515 static int
1516 fuse_vnop_reclaim(struct vop_reclaim_args *ap)
1517 {
1518 	struct vnode *vp = ap->a_vp;
1519 	struct thread *td = ap->a_td;
1520 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
1521 	struct fuse_filehandle *fufh, *fufh_tmp;
1522 
1523 	if (!fvdat) {
1524 		panic("FUSE: no vnode data during recycling");
1525 	}
1526 	LIST_FOREACH_SAFE(fufh, &fvdat->handles, next, fufh_tmp) {
1527 		printf("FUSE: vnode being reclaimed with open fufh "
1528 			"(type=%#x)", fufh->fufh_type);
1529 		fuse_filehandle_close(vp, fufh, td, NULL);
1530 	}
1531 
1532 	if (!fuse_isdeadfs(vp) && fvdat->nlookup > 0) {
1533 		fuse_internal_forget_send(vnode_mount(vp), td, NULL, VTOI(vp),
1534 		    fvdat->nlookup);
1535 	}
1536 	cache_purge(vp);
1537 	vfs_hash_remove(vp);
1538 	fuse_vnode_destroy(vp);
1539 
1540 	return 0;
1541 }
1542 
1543 /*
1544     struct vnop_remove_args {
1545 	struct vnode *a_dvp;
1546 	struct vnode *a_vp;
1547 	struct componentname *a_cnp;
1548     };
1549 */
1550 static int
1551 fuse_vnop_remove(struct vop_remove_args *ap)
1552 {
1553 	struct vnode *dvp = ap->a_dvp;
1554 	struct vnode *vp = ap->a_vp;
1555 	struct componentname *cnp = ap->a_cnp;
1556 
1557 	int err;
1558 
1559 	if (fuse_isdeadfs(vp)) {
1560 		return ENXIO;
1561 	}
1562 	if (vnode_isdir(vp)) {
1563 		return EPERM;
1564 	}
1565 
1566 	err = fuse_internal_remove(dvp, vp, cnp, FUSE_UNLINK);
1567 
1568 	return err;
1569 }
1570 
1571 /*
1572     struct vnop_rename_args {
1573 	struct vnode *a_fdvp;
1574 	struct vnode *a_fvp;
1575 	struct componentname *a_fcnp;
1576 	struct vnode *a_tdvp;
1577 	struct vnode *a_tvp;
1578 	struct componentname *a_tcnp;
1579     };
1580 */
1581 static int
1582 fuse_vnop_rename(struct vop_rename_args *ap)
1583 {
1584 	struct vnode *fdvp = ap->a_fdvp;
1585 	struct vnode *fvp = ap->a_fvp;
1586 	struct componentname *fcnp = ap->a_fcnp;
1587 	struct vnode *tdvp = ap->a_tdvp;
1588 	struct vnode *tvp = ap->a_tvp;
1589 	struct componentname *tcnp = ap->a_tcnp;
1590 	struct fuse_data *data;
1591 	bool newparent = fdvp != tdvp;
1592 	bool isdir = fvp->v_type == VDIR;
1593 	int err = 0;
1594 
1595 	if (fuse_isdeadfs(fdvp)) {
1596 		return ENXIO;
1597 	}
1598 	if (fvp->v_mount != tdvp->v_mount ||
1599 	    (tvp && fvp->v_mount != tvp->v_mount)) {
1600 		SDT_PROBE2(fusefs, , vnops, trace, 1, "cross-device rename");
1601 		err = EXDEV;
1602 		goto out;
1603 	}
1604 	cache_purge(fvp);
1605 
1606 	/*
1607 	 * FUSE library is expected to check if target directory is not
1608 	 * under the source directory in the file system tree.
1609 	 * Linux performs this check at VFS level.
1610 	 */
1611 	/*
1612 	 * If source is a directory, and it will get a new parent, user must
1613 	 * have write permission to it, so ".." can be modified.
1614 	 */
1615 	data = fuse_get_mpdata(vnode_mount(tdvp));
1616 	if (data->dataflags & FSESS_DEFAULT_PERMISSIONS && isdir && newparent) {
1617 		err = fuse_internal_access(fvp, VWRITE,
1618 			tcnp->cn_thread, tcnp->cn_cred);
1619 		if (err)
1620 			goto out;
1621 	}
1622 	sx_xlock(&data->rename_lock);
1623 	err = fuse_internal_rename(fdvp, fcnp, tdvp, tcnp);
1624 	if (err == 0) {
1625 		if (tdvp != fdvp)
1626 			fuse_vnode_setparent(fvp, tdvp);
1627 		if (tvp != NULL)
1628 			fuse_vnode_setparent(tvp, NULL);
1629 	}
1630 	sx_unlock(&data->rename_lock);
1631 
1632 	if (tvp != NULL && tvp != fvp) {
1633 		cache_purge(tvp);
1634 	}
1635 	if (vnode_isdir(fvp)) {
1636 		if ((tvp != NULL) && vnode_isdir(tvp)) {
1637 			cache_purge(tdvp);
1638 		}
1639 		cache_purge(fdvp);
1640 	}
1641 out:
1642 	if (tdvp == tvp) {
1643 		vrele(tdvp);
1644 	} else {
1645 		vput(tdvp);
1646 	}
1647 	if (tvp != NULL) {
1648 		vput(tvp);
1649 	}
1650 	vrele(fdvp);
1651 	vrele(fvp);
1652 
1653 	return err;
1654 }
1655 
1656 /*
1657     struct vnop_rmdir_args {
1658 	    struct vnode *a_dvp;
1659 	    struct vnode *a_vp;
1660 	    struct componentname *a_cnp;
1661     } *ap;
1662 */
1663 static int
1664 fuse_vnop_rmdir(struct vop_rmdir_args *ap)
1665 {
1666 	struct vnode *dvp = ap->a_dvp;
1667 	struct vnode *vp = ap->a_vp;
1668 
1669 	int err;
1670 
1671 	if (fuse_isdeadfs(vp)) {
1672 		return ENXIO;
1673 	}
1674 	if (VTOFUD(vp) == VTOFUD(dvp)) {
1675 		return EINVAL;
1676 	}
1677 	err = fuse_internal_remove(dvp, vp, ap->a_cnp, FUSE_RMDIR);
1678 
1679 	return err;
1680 }
1681 
1682 /*
1683     struct vnop_setattr_args {
1684 	struct vnode *a_vp;
1685 	struct vattr *a_vap;
1686 	struct ucred *a_cred;
1687 	struct thread *a_td;
1688     };
1689 */
1690 static int
1691 fuse_vnop_setattr(struct vop_setattr_args *ap)
1692 {
1693 	struct vnode *vp = ap->a_vp;
1694 	struct vattr *vap = ap->a_vap;
1695 	struct ucred *cred = ap->a_cred;
1696 	struct thread *td = curthread;
1697 	struct mount *mp;
1698 	struct fuse_data *data;
1699 	struct vattr old_va;
1700 	int dataflags;
1701 	int err = 0, err2;
1702 	accmode_t accmode = 0;
1703 	bool checkperm;
1704 	bool drop_suid = false;
1705 	gid_t cr_gid;
1706 
1707 	mp = vnode_mount(vp);
1708 	data = fuse_get_mpdata(mp);
1709 	dataflags = data->dataflags;
1710 	checkperm = dataflags & FSESS_DEFAULT_PERMISSIONS;
1711 	if (cred->cr_ngroups > 0)
1712 		cr_gid = cred->cr_groups[0];
1713 	else
1714 		cr_gid = 0;
1715 
1716 	if (fuse_isdeadfs(vp)) {
1717 		return ENXIO;
1718 	}
1719 
1720 	if (vap->va_uid != (uid_t)VNOVAL) {
1721 		if (checkperm) {
1722 			/* Only root may change a file's owner */
1723 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
1724 			if (err) {
1725 				/* As a special case, allow the null chown */
1726 				err2 = fuse_internal_getattr(vp, &old_va, cred,
1727 					td);
1728 				if (err2)
1729 					return (err2);
1730 				if (vap->va_uid != old_va.va_uid)
1731 					return err;
1732 				else
1733 					accmode |= VADMIN;
1734 				drop_suid = true;
1735 			} else
1736 				accmode |= VADMIN;
1737 		} else
1738 			accmode |= VADMIN;
1739 	}
1740 	if (vap->va_gid != (gid_t)VNOVAL) {
1741 		if (checkperm && priv_check_cred(cred, PRIV_VFS_CHOWN))
1742 			drop_suid = true;
1743 		if (checkperm && !groupmember(vap->va_gid, cred))
1744 		{
1745 			/*
1746 			 * Non-root users may only chgrp to one of their own
1747 			 * groups
1748 			 */
1749 			err = priv_check_cred(cred, PRIV_VFS_CHOWN);
1750 			if (err) {
1751 				/* As a special case, allow the null chgrp */
1752 				err2 = fuse_internal_getattr(vp, &old_va, cred,
1753 					td);
1754 				if (err2)
1755 					return (err2);
1756 				if (vap->va_gid != old_va.va_gid)
1757 					return err;
1758 				accmode |= VADMIN;
1759 			} else
1760 				accmode |= VADMIN;
1761 		} else
1762 			accmode |= VADMIN;
1763 	}
1764 	if (vap->va_size != VNOVAL) {
1765 		switch (vp->v_type) {
1766 		case VDIR:
1767 			return (EISDIR);
1768 		case VLNK:
1769 		case VREG:
1770 			if (vfs_isrdonly(mp))
1771 				return (EROFS);
1772 			break;
1773 		default:
1774 			/*
1775 			 * According to POSIX, the result is unspecified
1776 			 * for file types other than regular files,
1777 			 * directories and shared memory objects.  We
1778 			 * don't support shared memory objects in the file
1779 			 * system, and have dubious support for truncating
1780 			 * symlinks.  Just ignore the request in other cases.
1781 			 */
1782 			return (0);
1783 		}
1784 		/* Don't set accmode.  Permission to trunc is checked upstack */
1785 	}
1786 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
1787 		if (vap->va_vaflags & VA_UTIMES_NULL)
1788 			accmode |= VWRITE;
1789 		else
1790 			accmode |= VADMIN;
1791 	}
1792 	if (drop_suid) {
1793 		if (vap->va_mode != (mode_t)VNOVAL)
1794 			vap->va_mode &= ~(S_ISUID | S_ISGID);
1795 		else {
1796 			err = fuse_internal_getattr(vp, &old_va, cred, td);
1797 			if (err)
1798 				return (err);
1799 			vap->va_mode = old_va.va_mode & ~(S_ISUID | S_ISGID);
1800 		}
1801 	}
1802 	if (vap->va_mode != (mode_t)VNOVAL) {
1803 		/* Only root may set the sticky bit on non-directories */
1804 		if (checkperm && vp->v_type != VDIR && (vap->va_mode & S_ISTXT)
1805 		    && priv_check_cred(cred, PRIV_VFS_STICKYFILE))
1806 			return EFTYPE;
1807 		if (checkperm && (vap->va_mode & S_ISGID)) {
1808 			err = fuse_internal_getattr(vp, &old_va, cred, td);
1809 			if (err)
1810 				return (err);
1811 			if (!groupmember(old_va.va_gid, cred)) {
1812 				err = priv_check_cred(cred, PRIV_VFS_SETGID);
1813 				if (err)
1814 					return (err);
1815 			}
1816 		}
1817 		accmode |= VADMIN;
1818 	}
1819 
1820 	if (vfs_isrdonly(mp))
1821 		return EROFS;
1822 
1823 	err = fuse_internal_access(vp, accmode, td, cred);
1824 	if (err)
1825 		return err;
1826 	else
1827 		return fuse_internal_setattr(vp, vap, td, cred);
1828 }
1829 
1830 /*
1831     struct vnop_strategy_args {
1832 	struct vnode *a_vp;
1833 	struct buf *a_bp;
1834     };
1835 */
1836 static int
1837 fuse_vnop_strategy(struct vop_strategy_args *ap)
1838 {
1839 	struct vnode *vp = ap->a_vp;
1840 	struct buf *bp = ap->a_bp;
1841 
1842 	if (!vp || fuse_isdeadfs(vp)) {
1843 		bp->b_ioflags |= BIO_ERROR;
1844 		bp->b_error = ENXIO;
1845 		bufdone(bp);
1846 		return 0;
1847 	}
1848 
1849 	/*
1850 	 * VOP_STRATEGY always returns zero and signals error via bp->b_ioflags.
1851 	 * fuse_io_strategy sets bp's error fields
1852 	 */
1853 	(void)fuse_io_strategy(vp, bp);
1854 
1855 	return 0;
1856 }
1857 
1858 
1859 /*
1860     struct vnop_symlink_args {
1861 	struct vnode *a_dvp;
1862 	struct vnode **a_vpp;
1863 	struct componentname *a_cnp;
1864 	struct vattr *a_vap;
1865 	char *a_target;
1866     };
1867 */
1868 static int
1869 fuse_vnop_symlink(struct vop_symlink_args *ap)
1870 {
1871 	struct vnode *dvp = ap->a_dvp;
1872 	struct vnode **vpp = ap->a_vpp;
1873 	struct componentname *cnp = ap->a_cnp;
1874 	const char *target = ap->a_target;
1875 
1876 	struct fuse_dispatcher fdi;
1877 
1878 	int err;
1879 	size_t len;
1880 
1881 	if (fuse_isdeadfs(dvp)) {
1882 		return ENXIO;
1883 	}
1884 	/*
1885 	 * Unlike the other creator type calls, here we have to create a message
1886 	 * where the name of the new entry comes first, and the data describing
1887 	 * the entry comes second.
1888 	 * Hence we can't rely on our handy fuse_internal_newentry() routine,
1889 	 * but put together the message manually and just call the core part.
1890 	 */
1891 
1892 	len = strlen(target) + 1;
1893 	fdisp_init(&fdi, len + cnp->cn_namelen + 1);
1894 	fdisp_make_vp(&fdi, FUSE_SYMLINK, dvp, curthread, NULL);
1895 
1896 	memcpy(fdi.indata, cnp->cn_nameptr, cnp->cn_namelen);
1897 	((char *)fdi.indata)[cnp->cn_namelen] = '\0';
1898 	memcpy((char *)fdi.indata + cnp->cn_namelen + 1, target, len);
1899 
1900 	err = fuse_internal_newentry_core(dvp, vpp, cnp, VLNK, &fdi);
1901 	fdisp_destroy(&fdi);
1902 	return err;
1903 }
1904 
1905 /*
1906     struct vnop_write_args {
1907 	struct vnode *a_vp;
1908 	struct uio *a_uio;
1909 	int  a_ioflag;
1910 	struct ucred *a_cred;
1911     };
1912 */
1913 static int
1914 fuse_vnop_write(struct vop_write_args *ap)
1915 {
1916 	struct vnode *vp = ap->a_vp;
1917 	struct uio *uio = ap->a_uio;
1918 	int ioflag = ap->a_ioflag;
1919 	struct ucred *cred = ap->a_cred;
1920 	pid_t pid = curthread->td_proc->p_pid;
1921 
1922 	if (fuse_isdeadfs(vp)) {
1923 		return ENXIO;
1924 	}
1925 
1926 	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
1927 		ioflag |= IO_DIRECT;
1928 	}
1929 
1930 	return fuse_io_dispatch(vp, uio, ioflag, cred, pid);
1931 }
1932 
1933 static daddr_t
1934 fuse_gbp_getblkno(struct vnode *vp, vm_ooffset_t off)
1935 {
1936 	const int biosize = fuse_iosize(vp);
1937 
1938 	return (off / biosize);
1939 }
1940 
1941 static int
1942 fuse_gbp_getblksz(struct vnode *vp, daddr_t lbn)
1943 {
1944 	off_t filesize;
1945 	int blksz, err;
1946 	const int biosize = fuse_iosize(vp);
1947 
1948 	err = fuse_vnode_size(vp, &filesize, NULL, NULL);
1949 	KASSERT(err == 0, ("vfs_bio_getpages can't handle errors here"));
1950 	if (err)
1951 		return biosize;
1952 
1953 	if ((off_t)lbn * biosize >= filesize) {
1954 		blksz = 0;
1955 	} else if ((off_t)(lbn + 1) * biosize > filesize) {
1956 		blksz = filesize - (off_t)lbn *biosize;
1957 	} else {
1958 		blksz = biosize;
1959 	}
1960 	return (blksz);
1961 }
1962 
1963 /*
1964     struct vnop_getpages_args {
1965 	struct vnode *a_vp;
1966 	vm_page_t *a_m;
1967 	int a_count;
1968 	int a_reqpage;
1969     };
1970 */
1971 static int
1972 fuse_vnop_getpages(struct vop_getpages_args *ap)
1973 {
1974 	struct vnode *vp = ap->a_vp;
1975 
1976 	if (!fsess_opt_mmap(vnode_mount(vp))) {
1977 		SDT_PROBE2(fusefs, , vnops, trace, 1,
1978 			"called on non-cacheable vnode??\n");
1979 		return (VM_PAGER_ERROR);
1980 	}
1981 
1982 	return (vfs_bio_getpages(vp, ap->a_m, ap->a_count, ap->a_rbehind,
1983 	    ap->a_rahead, fuse_gbp_getblkno, fuse_gbp_getblksz));
1984 }
1985 
1986 static const char extattr_namespace_separator = '.';
1987 
1988 /*
1989     struct vop_getextattr_args {
1990 	struct vop_generic_args a_gen;
1991 	struct vnode *a_vp;
1992 	int a_attrnamespace;
1993 	const char *a_name;
1994 	struct uio *a_uio;
1995 	size_t *a_size;
1996 	struct ucred *a_cred;
1997 	struct thread *a_td;
1998     };
1999 */
2000 static int
2001 fuse_vnop_getextattr(struct vop_getextattr_args *ap)
2002 {
2003 	struct vnode *vp = ap->a_vp;
2004 	struct uio *uio = ap->a_uio;
2005 	struct fuse_dispatcher fdi;
2006 	struct fuse_getxattr_in *get_xattr_in;
2007 	struct fuse_getxattr_out *get_xattr_out;
2008 	struct mount *mp = vnode_mount(vp);
2009 	struct thread *td = ap->a_td;
2010 	struct ucred *cred = ap->a_cred;
2011 	char *prefix;
2012 	char *attr_str;
2013 	size_t len;
2014 	int err;
2015 
2016 	if (fuse_isdeadfs(vp))
2017 		return (ENXIO);
2018 
2019 	if (!fsess_isimpl(mp, FUSE_GETXATTR))
2020 		return EOPNOTSUPP;
2021 
2022 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2023 	if (err)
2024 		return err;
2025 
2026 	/* Default to looking for user attributes. */
2027 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2028 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2029 	else
2030 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2031 
2032 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2033 	    strlen(ap->a_name) + 1;
2034 
2035 	fdisp_init(&fdi, len + sizeof(*get_xattr_in));
2036 	fdisp_make_vp(&fdi, FUSE_GETXATTR, vp, td, cred);
2037 
2038 	get_xattr_in = fdi.indata;
2039 	/*
2040 	 * Check to see whether we're querying the available size or
2041 	 * issuing the actual request.  If we pass in 0, we get back struct
2042 	 * fuse_getxattr_out.  If we pass in a non-zero size, we get back
2043 	 * that much data, without the struct fuse_getxattr_out header.
2044 	 */
2045 	if (uio == NULL)
2046 		get_xattr_in->size = 0;
2047 	else
2048 		get_xattr_in->size = uio->uio_resid;
2049 
2050 	attr_str = (char *)fdi.indata + sizeof(*get_xattr_in);
2051 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2052 	    ap->a_name);
2053 
2054 	err = fdisp_wait_answ(&fdi);
2055 	if (err != 0) {
2056 		if (err == ENOSYS) {
2057 			fsess_set_notimpl(mp, FUSE_GETXATTR);
2058 			err = EOPNOTSUPP;
2059 		}
2060 		goto out;
2061 	}
2062 
2063 	get_xattr_out = fdi.answ;
2064 
2065 	if (ap->a_size != NULL)
2066 		*ap->a_size = get_xattr_out->size;
2067 
2068 	if (uio != NULL)
2069 		err = uiomove(fdi.answ, fdi.iosize, uio);
2070 
2071 out:
2072 	fdisp_destroy(&fdi);
2073 	return (err);
2074 }
2075 
2076 /*
2077     struct vop_setextattr_args {
2078 	struct vop_generic_args a_gen;
2079 	struct vnode *a_vp;
2080 	int a_attrnamespace;
2081 	const char *a_name;
2082 	struct uio *a_uio;
2083 	struct ucred *a_cred;
2084 	struct thread *a_td;
2085     };
2086 */
2087 static int
2088 fuse_vnop_setextattr(struct vop_setextattr_args *ap)
2089 {
2090 	struct vnode *vp = ap->a_vp;
2091 	struct uio *uio = ap->a_uio;
2092 	struct fuse_dispatcher fdi;
2093 	struct fuse_setxattr_in *set_xattr_in;
2094 	struct mount *mp = vnode_mount(vp);
2095 	struct thread *td = ap->a_td;
2096 	struct ucred *cred = ap->a_cred;
2097 	char *prefix;
2098 	size_t len;
2099 	char *attr_str;
2100 	int err;
2101 
2102 	if (fuse_isdeadfs(vp))
2103 		return (ENXIO);
2104 
2105 	if (!fsess_isimpl(mp, FUSE_SETXATTR))
2106 		return EOPNOTSUPP;
2107 
2108 	if (vfs_isrdonly(mp))
2109 		return EROFS;
2110 
2111 	/* Deleting xattrs must use VOP_DELETEEXTATTR instead */
2112 	if (ap->a_uio == NULL) {
2113 		/*
2114 		 * If we got here as fallback from VOP_DELETEEXTATTR, then
2115 		 * return EOPNOTSUPP.
2116 		 */
2117 		if (!fsess_isimpl(mp, FUSE_REMOVEXATTR))
2118 			return (EOPNOTSUPP);
2119 		else
2120 			return (EINVAL);
2121 	}
2122 
2123 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
2124 		VWRITE);
2125 	if (err)
2126 		return err;
2127 
2128 	/* Default to looking for user attributes. */
2129 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2130 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2131 	else
2132 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2133 
2134 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2135 	    strlen(ap->a_name) + 1;
2136 
2137 	fdisp_init(&fdi, len + sizeof(*set_xattr_in) + uio->uio_resid);
2138 	fdisp_make_vp(&fdi, FUSE_SETXATTR, vp, td, cred);
2139 
2140 	set_xattr_in = fdi.indata;
2141 	set_xattr_in->size = uio->uio_resid;
2142 
2143 	attr_str = (char *)fdi.indata + sizeof(*set_xattr_in);
2144 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2145 	    ap->a_name);
2146 
2147 	err = uiomove((char *)fdi.indata + sizeof(*set_xattr_in) + len,
2148 	    uio->uio_resid, uio);
2149 	if (err != 0) {
2150 		goto out;
2151 	}
2152 
2153 	err = fdisp_wait_answ(&fdi);
2154 
2155 	if (err == ENOSYS) {
2156 		fsess_set_notimpl(mp, FUSE_SETXATTR);
2157 		err = EOPNOTSUPP;
2158 	}
2159 	if (err == ERESTART) {
2160 		/* Can't restart after calling uiomove */
2161 		err = EINTR;
2162 	}
2163 
2164 out:
2165 	fdisp_destroy(&fdi);
2166 	return (err);
2167 }
2168 
2169 /*
2170  * The Linux / FUSE extended attribute list is simply a collection of
2171  * NUL-terminated strings.  The FreeBSD extended attribute list is a single
2172  * byte length followed by a non-NUL terminated string.  So, this allows
2173  * conversion of the Linux / FUSE format to the FreeBSD format in place.
2174  * Linux attribute names are reported with the namespace as a prefix (e.g.
2175  * "user.attribute_name"), but in FreeBSD they are reported without the
2176  * namespace prefix (e.g. "attribute_name").  So, we're going from:
2177  *
2178  * user.attr_name1\0user.attr_name2\0
2179  *
2180  * to:
2181  *
2182  * <num>attr_name1<num>attr_name2
2183  *
2184  * Where "<num>" is a single byte number of characters in the attribute name.
2185  *
2186  * Args:
2187  * prefix - exattr namespace prefix string
2188  * list, list_len - input list with namespace prefixes
2189  * bsd_list, bsd_list_len - output list compatible with bsd vfs
2190  */
2191 static int
2192 fuse_xattrlist_convert(char *prefix, const char *list, int list_len,
2193     char *bsd_list, int *bsd_list_len)
2194 {
2195 	int len, pos, dist_to_next, prefix_len;
2196 
2197 	pos = 0;
2198 	*bsd_list_len = 0;
2199 	prefix_len = strlen(prefix);
2200 
2201 	while (pos < list_len && list[pos] != '\0') {
2202 		dist_to_next = strlen(&list[pos]) + 1;
2203 		if (bcmp(&list[pos], prefix, prefix_len) == 0 &&
2204 		    list[pos + prefix_len] == extattr_namespace_separator) {
2205 			len = dist_to_next -
2206 			    (prefix_len + sizeof(extattr_namespace_separator)) - 1;
2207 			if (len >= EXTATTR_MAXNAMELEN)
2208 				return (ENAMETOOLONG);
2209 
2210 			bsd_list[*bsd_list_len] = len;
2211 			memcpy(&bsd_list[*bsd_list_len + 1],
2212 			    &list[pos + prefix_len +
2213 			    sizeof(extattr_namespace_separator)], len);
2214 
2215 			*bsd_list_len += len + 1;
2216 		}
2217 
2218 		pos += dist_to_next;
2219 	}
2220 
2221 	return (0);
2222 }
2223 
2224 /*
2225  * List extended attributes
2226  *
2227  * The FUSE_LISTXATTR operation is based on Linux's listxattr(2) syscall, which
2228  * has a number of differences compared to its FreeBSD equivalent,
2229  * extattr_list_file:
2230  *
2231  * - FUSE_LISTXATTR returns all extended attributes across all namespaces,
2232  *   whereas listxattr(2) only returns attributes for a single namespace
2233  * - FUSE_LISTXATTR prepends each attribute name with "namespace."
2234  * - If the provided buffer is not large enough to hold the result,
2235  *   FUSE_LISTXATTR should return ERANGE, whereas listxattr is expected to
2236  *   return as many results as will fit.
2237  */
2238 /*
2239     struct vop_listextattr_args {
2240 	struct vop_generic_args a_gen;
2241 	struct vnode *a_vp;
2242 	int a_attrnamespace;
2243 	struct uio *a_uio;
2244 	size_t *a_size;
2245 	struct ucred *a_cred;
2246 	struct thread *a_td;
2247     };
2248 */
2249 static int
2250 fuse_vnop_listextattr(struct vop_listextattr_args *ap)
2251 {
2252 	struct vnode *vp = ap->a_vp;
2253 	struct uio *uio = ap->a_uio;
2254 	struct fuse_dispatcher fdi;
2255 	struct fuse_listxattr_in *list_xattr_in;
2256 	struct fuse_listxattr_out *list_xattr_out;
2257 	struct mount *mp = vnode_mount(vp);
2258 	struct thread *td = ap->a_td;
2259 	struct ucred *cred = ap->a_cred;
2260 	char *prefix;
2261 	char *bsd_list = NULL;
2262 	char *linux_list;
2263 	int bsd_list_len;
2264 	int linux_list_len;
2265 	int err;
2266 
2267 	if (fuse_isdeadfs(vp))
2268 		return (ENXIO);
2269 
2270 	if (!fsess_isimpl(mp, FUSE_LISTXATTR))
2271 		return EOPNOTSUPP;
2272 
2273 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td, VREAD);
2274 	if (err)
2275 		return err;
2276 
2277 	/*
2278 	 * Add space for a NUL and the period separator if enabled.
2279 	 * Default to looking for user attributes.
2280 	 */
2281 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2282 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2283 	else
2284 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2285 
2286 	fdisp_init(&fdi, sizeof(*list_xattr_in));
2287 	fdisp_make_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2288 
2289 	/*
2290 	 * Retrieve Linux / FUSE compatible list size.
2291 	 */
2292 	list_xattr_in = fdi.indata;
2293 	list_xattr_in->size = 0;
2294 
2295 	err = fdisp_wait_answ(&fdi);
2296 	if (err != 0) {
2297 		if (err == ENOSYS) {
2298 			fsess_set_notimpl(mp, FUSE_LISTXATTR);
2299 			err = EOPNOTSUPP;
2300 		}
2301 		goto out;
2302 	}
2303 
2304 	list_xattr_out = fdi.answ;
2305 	linux_list_len = list_xattr_out->size;
2306 	if (linux_list_len == 0) {
2307 		if (ap->a_size != NULL)
2308 			*ap->a_size = linux_list_len;
2309 		goto out;
2310 	}
2311 
2312 	/*
2313 	 * Retrieve Linux / FUSE compatible list values.
2314 	 */
2315 	fdisp_refresh_vp(&fdi, FUSE_LISTXATTR, vp, td, cred);
2316 	list_xattr_in = fdi.indata;
2317 	list_xattr_in->size = linux_list_len;
2318 
2319 	err = fdisp_wait_answ(&fdi);
2320 	if (err == ERANGE) {
2321 		/*
2322 		 * Race detected.  The attribute list must've grown since the
2323 		 * first FUSE_LISTXATTR call.  Start over.  Go all the way back
2324 		 * to userland so we can process signals, if necessary, before
2325 		 * restarting.
2326 		 */
2327 		err = ERESTART;
2328 		goto out;
2329 	} else if (err != 0)
2330 		goto out;
2331 
2332 	linux_list = fdi.answ;
2333 	/* FUSE doesn't allow the server to return more data than requested */
2334 	if (fdi.iosize > linux_list_len) {
2335 		printf("WARNING: FUSE protocol violation.  Server returned "
2336 			"more extended attribute data than requested; "
2337 			"should've returned ERANGE instead");
2338 	} else {
2339 		/* But returning less data is fine */
2340 		linux_list_len = fdi.iosize;
2341 	}
2342 
2343 	/*
2344 	 * Retrieve the BSD compatible list values.
2345 	 * The Linux / FUSE attribute list format isn't the same
2346 	 * as FreeBSD's format. So we need to transform it into
2347 	 * FreeBSD's format before giving it to the user.
2348 	 */
2349 	bsd_list = malloc(linux_list_len, M_TEMP, M_WAITOK);
2350 	err = fuse_xattrlist_convert(prefix, linux_list, linux_list_len,
2351 	    bsd_list, &bsd_list_len);
2352 	if (err != 0)
2353 		goto out;
2354 
2355 	if (ap->a_size != NULL)
2356 		*ap->a_size = bsd_list_len;
2357 
2358 	if (uio != NULL)
2359 		err = uiomove(bsd_list, bsd_list_len, uio);
2360 
2361 out:
2362 	free(bsd_list, M_TEMP);
2363 	fdisp_destroy(&fdi);
2364 	return (err);
2365 }
2366 
2367 /*
2368     struct vop_deleteextattr_args {
2369 	struct vop_generic_args a_gen;
2370 	struct vnode *a_vp;
2371 	int a_attrnamespace;
2372 	const char *a_name;
2373 	struct ucred *a_cred;
2374 	struct thread *a_td;
2375     };
2376 */
2377 static int
2378 fuse_vnop_deleteextattr(struct vop_deleteextattr_args *ap)
2379 {
2380 	struct vnode *vp = ap->a_vp;
2381 	struct fuse_dispatcher fdi;
2382 	struct mount *mp = vnode_mount(vp);
2383 	struct thread *td = ap->a_td;
2384 	struct ucred *cred = ap->a_cred;
2385 	char *prefix;
2386 	size_t len;
2387 	char *attr_str;
2388 	int err;
2389 
2390 	if (fuse_isdeadfs(vp))
2391 		return (ENXIO);
2392 
2393 	if (!fsess_isimpl(mp, FUSE_REMOVEXATTR))
2394 		return EOPNOTSUPP;
2395 
2396 	if (vfs_isrdonly(mp))
2397 		return EROFS;
2398 
2399 	err = fuse_extattr_check_cred(vp, ap->a_attrnamespace, cred, td,
2400 		VWRITE);
2401 	if (err)
2402 		return err;
2403 
2404 	/* Default to looking for user attributes. */
2405 	if (ap->a_attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
2406 		prefix = EXTATTR_NAMESPACE_SYSTEM_STRING;
2407 	else
2408 		prefix = EXTATTR_NAMESPACE_USER_STRING;
2409 
2410 	len = strlen(prefix) + sizeof(extattr_namespace_separator) +
2411 	    strlen(ap->a_name) + 1;
2412 
2413 	fdisp_init(&fdi, len);
2414 	fdisp_make_vp(&fdi, FUSE_REMOVEXATTR, vp, td, cred);
2415 
2416 	attr_str = fdi.indata;
2417 	snprintf(attr_str, len, "%s%c%s", prefix, extattr_namespace_separator,
2418 	    ap->a_name);
2419 
2420 	err = fdisp_wait_answ(&fdi);
2421 	if (err == ENOSYS) {
2422 		fsess_set_notimpl(mp, FUSE_REMOVEXATTR);
2423 		err = EOPNOTSUPP;
2424 	}
2425 
2426 	fdisp_destroy(&fdi);
2427 	return (err);
2428 }
2429 
2430 /*
2431     struct vnop_print_args {
2432 	struct vnode *a_vp;
2433     };
2434 */
2435 static int
2436 fuse_vnop_print(struct vop_print_args *ap)
2437 {
2438 	struct fuse_vnode_data *fvdat = VTOFUD(ap->a_vp);
2439 
2440 	printf("nodeid: %ju, parent nodeid: %ju, nlookup: %ju, flag: %#x\n",
2441 	    (uintmax_t)VTOILLU(ap->a_vp), (uintmax_t)fvdat->parent_nid,
2442 	    (uintmax_t)fvdat->nlookup,
2443 	    fvdat->flag);
2444 
2445 	return 0;
2446 }
2447 
2448 /*
2449  * Get an NFS filehandle for a FUSE file.
2450  *
2451  * This will only work for FUSE file systems that guarantee the uniqueness of
2452  * nodeid:generation, which most don't.
2453  */
2454 /*
2455 vop_vptofh {
2456 	IN struct vnode *a_vp;
2457 	IN struct fid *a_fhp;
2458 };
2459 */
2460 static int
2461 fuse_vnop_vptofh(struct vop_vptofh_args *ap)
2462 {
2463 	struct vnode *vp = ap->a_vp;
2464 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
2465 	struct fuse_fid *fhp = (struct fuse_fid *)(ap->a_fhp);
2466 	_Static_assert(sizeof(struct fuse_fid) <= sizeof(struct fid),
2467 		"FUSE fid type is too big");
2468 	struct mount *mp = vnode_mount(vp);
2469 	struct fuse_data *data = fuse_get_mpdata(mp);
2470 	struct vattr va;
2471 	int err;
2472 
2473 	if (!(data->dataflags & FSESS_EXPORT_SUPPORT))
2474 		return EOPNOTSUPP;
2475 
2476 	err = fuse_internal_getattr(vp, &va, curthread->td_ucred, curthread);
2477 	if (err)
2478 		return err;
2479 
2480 	/*ip = VTOI(ap->a_vp);*/
2481 	/*ufhp = (struct ufid *)ap->a_fhp;*/
2482 	fhp->len = sizeof(struct fuse_fid);
2483 	fhp->nid = fvdat->nid;
2484 	if (fvdat->generation <= UINT32_MAX)
2485 		fhp->gen = fvdat->generation;
2486 	else
2487 		return EOVERFLOW;
2488 	return (0);
2489 }
2490 
2491 
2492