xref: /freebsd/sys/compat/linux/linux_file.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1994-1995 Søren Schmidt
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
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/dirent.h>
32 #include <sys/fcntl.h>
33 #include <sys/file.h>
34 #include <sys/filedesc.h>
35 #include <sys/lock.h>
36 #include <sys/mman.h>
37 #include <sys/selinfo.h>
38 #include <sys/pipe.h>
39 #include <sys/proc.h>
40 #include <sys/stat.h>
41 #include <sys/sx.h>
42 #include <sys/syscallsubr.h>
43 #include <sys/sysproto.h>
44 #include <sys/tty.h>
45 #include <sys/unistd.h>
46 #include <sys/vnode.h>
47 
48 #ifdef COMPAT_LINUX32
49 #include <compat/freebsd32/freebsd32_misc.h>
50 #include <compat/freebsd32/freebsd32_util.h>
51 #include <machine/../linux32/linux.h>
52 #include <machine/../linux32/linux32_proto.h>
53 #else
54 #include <machine/../linux/linux.h>
55 #include <machine/../linux/linux_proto.h>
56 #endif
57 #include <compat/linux/linux_misc.h>
58 #include <compat/linux/linux_util.h>
59 #include <compat/linux/linux_file.h>
60 
61 static int	linux_common_open(struct thread *, int, const char *, int, int,
62 		    enum uio_seg);
63 static int	linux_do_accessat(struct thread *t, int, const char *, int, int);
64 static int	linux_getdents_error(struct thread *, int, int);
65 
66 static struct bsd_to_linux_bitmap seal_bitmap[] = {
67 	BITMAP_1t1_LINUX(F_SEAL_SEAL),
68 	BITMAP_1t1_LINUX(F_SEAL_SHRINK),
69 	BITMAP_1t1_LINUX(F_SEAL_GROW),
70 	BITMAP_1t1_LINUX(F_SEAL_WRITE),
71 };
72 
73 #define	MFD_HUGETLB_ENTRY(_size)					\
74 	{								\
75 		.bsd_value = MFD_HUGE_##_size,				\
76 		.linux_value = LINUX_HUGETLB_FLAG_ENCODE_##_size	\
77 	}
78 static struct bsd_to_linux_bitmap mfd_bitmap[] = {
79 	BITMAP_1t1_LINUX(MFD_CLOEXEC),
80 	BITMAP_1t1_LINUX(MFD_ALLOW_SEALING),
81 	BITMAP_1t1_LINUX(MFD_HUGETLB),
82 	MFD_HUGETLB_ENTRY(64KB),
83 	MFD_HUGETLB_ENTRY(512KB),
84 	MFD_HUGETLB_ENTRY(1MB),
85 	MFD_HUGETLB_ENTRY(2MB),
86 	MFD_HUGETLB_ENTRY(8MB),
87 	MFD_HUGETLB_ENTRY(16MB),
88 	MFD_HUGETLB_ENTRY(32MB),
89 	MFD_HUGETLB_ENTRY(256MB),
90 	MFD_HUGETLB_ENTRY(512MB),
91 	MFD_HUGETLB_ENTRY(1GB),
92 	MFD_HUGETLB_ENTRY(2GB),
93 	MFD_HUGETLB_ENTRY(16GB),
94 };
95 #undef MFD_HUGETLB_ENTRY
96 
97 #ifdef LINUX_LEGACY_SYSCALLS
98 int
99 linux_creat(struct thread *td, struct linux_creat_args *args)
100 {
101 
102 	return (kern_openat(td, AT_FDCWD, args->path, UIO_USERSPACE,
103 	    O_WRONLY | O_CREAT | O_TRUNC, args->mode));
104 }
105 #endif
106 
107 static int
108 linux_common_openflags(int l_flags)
109 {
110 	int bsd_flags;
111 
112 	bsd_flags = 0;
113 	switch (l_flags & LINUX_O_ACCMODE) {
114 	case LINUX_O_WRONLY:
115 		bsd_flags |= O_WRONLY;
116 		break;
117 	case LINUX_O_RDWR:
118 		bsd_flags |= O_RDWR;
119 		break;
120 	default:
121 		bsd_flags |= O_RDONLY;
122 	}
123 	if (l_flags & LINUX_O_NDELAY)
124 		bsd_flags |= O_NONBLOCK;
125 	if (l_flags & LINUX_O_APPEND)
126 		bsd_flags |= O_APPEND;
127 	if (l_flags & LINUX_O_SYNC)
128 		bsd_flags |= O_FSYNC;
129 	if (l_flags & LINUX_O_CLOEXEC)
130 		bsd_flags |= O_CLOEXEC;
131 	if (l_flags & LINUX_O_NONBLOCK)
132 		bsd_flags |= O_NONBLOCK;
133 	if (l_flags & LINUX_O_ASYNC)
134 		bsd_flags |= O_ASYNC;
135 	if (l_flags & LINUX_O_CREAT)
136 		bsd_flags |= O_CREAT;
137 	if (l_flags & LINUX_O_TRUNC)
138 		bsd_flags |= O_TRUNC;
139 	if (l_flags & LINUX_O_EXCL)
140 		bsd_flags |= O_EXCL;
141 	if (l_flags & LINUX_O_NOCTTY)
142 		bsd_flags |= O_NOCTTY;
143 	if (l_flags & LINUX_O_DIRECT)
144 		bsd_flags |= O_DIRECT;
145 	if (l_flags & LINUX_O_NOFOLLOW)
146 		bsd_flags |= O_NOFOLLOW;
147 	if (l_flags & LINUX_O_DIRECTORY)
148 		bsd_flags |= O_DIRECTORY;
149 	if (l_flags & LINUX_O_PATH)
150 		bsd_flags |= O_PATH;
151 	/* XXX LINUX_O_NOATIME: unable to be easily implemented. */
152 	return (bsd_flags);
153 }
154 
155 static int
156 linux_common_open(struct thread *td, int dirfd, const char *path, int l_flags,
157     int mode, enum uio_seg seg)
158 {
159 	struct proc *p = td->td_proc;
160 	struct file *fp;
161 	int fd;
162 	int bsd_flags, error;
163 
164 	bsd_flags = linux_common_openflags(l_flags);
165 	error = kern_openat(td, dirfd, path, seg, bsd_flags, mode);
166 	if (error != 0) {
167 		if (error == EMLINK)
168 			error = ELOOP;
169 		goto done;
170 	}
171 	if (p->p_flag & P_CONTROLT)
172 		goto done;
173 	if (bsd_flags & O_NOCTTY)
174 		goto done;
175 
176 	/*
177 	 * XXX In between kern_openat() and fget(), another process
178 	 * having the same filedesc could use that fd without
179 	 * checking below.
180 	*/
181 	fd = td->td_retval[0];
182 	if (fget(td, fd, &cap_ioctl_rights, &fp) == 0) {
183 		if (fp->f_type != DTYPE_VNODE) {
184 			fdrop(fp, td);
185 			goto done;
186 		}
187 		sx_slock(&proctree_lock);
188 		PROC_LOCK(p);
189 		if (SESS_LEADER(p) && !(p->p_flag & P_CONTROLT)) {
190 			PROC_UNLOCK(p);
191 			sx_sunlock(&proctree_lock);
192 			/* XXXPJD: Verify if TIOCSCTTY is allowed. */
193 			(void) fo_ioctl(fp, TIOCSCTTY, (caddr_t) 0,
194 			    td->td_ucred, td);
195 		} else {
196 			PROC_UNLOCK(p);
197 			sx_sunlock(&proctree_lock);
198 		}
199 		fdrop(fp, td);
200 	}
201 
202 done:
203 	return (error);
204 }
205 
206 int
207 linux_openat(struct thread *td, struct linux_openat_args *args)
208 {
209 	int dfd;
210 
211 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
212 	return (linux_common_open(td, dfd, args->filename, args->flags,
213 	    args->mode, UIO_USERSPACE));
214 }
215 
216 #ifdef LINUX_LEGACY_SYSCALLS
217 int
218 linux_open(struct thread *td, struct linux_open_args *args)
219 {
220 
221 	return (linux_common_open(td, AT_FDCWD, args->path, args->flags,
222 	    args->mode, UIO_USERSPACE));
223 }
224 #endif
225 
226 int
227 linux_name_to_handle_at(struct thread *td,
228     struct linux_name_to_handle_at_args *args)
229 {
230 	static const l_int valid_flags = (LINUX_AT_SYMLINK_FOLLOW |
231 	    LINUX_AT_EMPTY_PATH);
232 	static const l_uint fh_size = sizeof(fhandle_t);
233 
234 	fhandle_t fh;
235 	l_uint fh_bytes;
236 	l_int mount_id;
237 	int error, fd, bsd_flags;
238 
239 	if (args->flags & ~valid_flags)
240 		return (EINVAL);
241 
242 	fd = args->dirfd;
243 	if (fd == LINUX_AT_FDCWD)
244 		fd = AT_FDCWD;
245 
246 	bsd_flags = 0;
247 	if (!(args->flags & LINUX_AT_SYMLINK_FOLLOW))
248 		bsd_flags |= AT_SYMLINK_NOFOLLOW;
249 	if ((args->flags & LINUX_AT_EMPTY_PATH) != 0)
250 		bsd_flags |= AT_EMPTY_PATH;
251 
252 	error = kern_getfhat(td, bsd_flags, fd, args->name,
253 	    UIO_USERSPACE, &fh, UIO_SYSSPACE);
254 	if (error != 0)
255 		return (error);
256 
257 	/* Emit mount_id -- required before EOVERFLOW case. */
258 	mount_id = (fh.fh_fsid.val[0] ^ fh.fh_fsid.val[1]);
259 	error = copyout(&mount_id, args->mnt_id, sizeof(mount_id));
260 	if (error != 0)
261 		return (error);
262 
263 	/* Check if there is room for handle. */
264 	error = copyin(&args->handle->handle_bytes, &fh_bytes,
265 	    sizeof(fh_bytes));
266 	if (error != 0)
267 		return (error);
268 
269 	if (fh_bytes < fh_size) {
270 		error = copyout(&fh_size, &args->handle->handle_bytes,
271 		    sizeof(fh_size));
272 		if (error == 0)
273 			error = EOVERFLOW;
274 		return (error);
275 	}
276 
277 	/* Emit handle. */
278 	mount_id = 0;
279 	/*
280 	 * We don't use handle_type for anything yet, but initialize a known
281 	 * value.
282 	 */
283 	error = copyout(&mount_id, &args->handle->handle_type,
284 	    sizeof(mount_id));
285 	if (error != 0)
286 		return (error);
287 
288 	error = copyout(&fh, &args->handle->f_handle,
289 	    sizeof(fh));
290 	return (error);
291 }
292 
293 int
294 linux_open_by_handle_at(struct thread *td,
295     struct linux_open_by_handle_at_args *args)
296 {
297 	l_uint fh_bytes;
298 	int bsd_flags, error;
299 
300 	error = copyin(&args->handle->handle_bytes, &fh_bytes,
301 	    sizeof(fh_bytes));
302 	if (error != 0)
303 		return (error);
304 
305 	if (fh_bytes < sizeof(fhandle_t))
306 		return (EINVAL);
307 
308 	bsd_flags = linux_common_openflags(args->flags);
309 	return (kern_fhopen(td, (void *)&args->handle->f_handle, bsd_flags));
310 }
311 
312 int
313 linux_lseek(struct thread *td, struct linux_lseek_args *args)
314 {
315 
316 	return (kern_lseek(td, args->fdes, args->off, args->whence));
317 }
318 
319 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
320 int
321 linux_llseek(struct thread *td, struct linux_llseek_args *args)
322 {
323 	int error;
324 	off_t off;
325 
326 	off = (args->olow) | (((off_t) args->ohigh) << 32);
327 
328 	error = kern_lseek(td, args->fd, off, args->whence);
329 	if (error != 0)
330 		return (error);
331 
332 	error = copyout(td->td_retval, args->res, sizeof(off_t));
333 	if (error != 0)
334 		return (error);
335 
336 	td->td_retval[0] = 0;
337 	return (0);
338 }
339 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
340 
341 /*
342  * Note that linux_getdents(2) and linux_getdents64(2) have the same
343  * arguments. They only differ in the definition of struct dirent they
344  * operate on.
345  * Note that linux_readdir(2) is a special case of linux_getdents(2)
346  * where count is always equals 1, meaning that the buffer is one
347  * dirent-structure in size and that the code can't handle more anyway.
348  * Note that linux_readdir(2) can't be implemented by means of linux_getdents(2)
349  * as in case when the *dent buffer size is equal to 1 linux_getdents(2) will
350  * trash user stack.
351  */
352 
353 static int
354 linux_getdents_error(struct thread *td, int fd, int err)
355 {
356 	struct vnode *vp;
357 	struct file *fp;
358 	int error;
359 
360 	/* Linux return ENOTDIR in case when fd is not a directory. */
361 	error = getvnode(td, fd, &cap_read_rights, &fp);
362 	if (error != 0)
363 		return (error);
364 	vp = fp->f_vnode;
365 	if (vp->v_type != VDIR) {
366 		fdrop(fp, td);
367 		return (ENOTDIR);
368 	}
369 	fdrop(fp, td);
370 	return (err);
371 }
372 
373 struct l_dirent {
374 	l_ulong		d_ino;
375 	l_off_t		d_off;
376 	l_ushort	d_reclen;
377 	char		d_name[LINUX_NAME_MAX + 1];
378 };
379 
380 struct l_dirent64 {
381 	uint64_t	d_ino;
382 	int64_t		d_off;
383 	l_ushort	d_reclen;
384 	u_char		d_type;
385 	char		d_name[LINUX_NAME_MAX + 1];
386 };
387 
388 /*
389  * Linux uses the last byte in the dirent buffer to store d_type,
390  * at least glibc-2.7 requires it. That is why l_dirent is padded with 2 bytes.
391  */
392 #define LINUX_RECLEN(namlen)						\
393     roundup(offsetof(struct l_dirent, d_name) + (namlen) + 2, sizeof(l_ulong))
394 
395 #define LINUX_RECLEN64(namlen)						\
396     roundup(offsetof(struct l_dirent64, d_name) + (namlen) + 1,		\
397     sizeof(uint64_t))
398 
399 #ifdef LINUX_LEGACY_SYSCALLS
400 int
401 linux_getdents(struct thread *td, struct linux_getdents_args *args)
402 {
403 	struct dirent *bdp;
404 	caddr_t inp, buf;		/* BSD-format */
405 	int len, reclen;		/* BSD-format */
406 	caddr_t outp;			/* Linux-format */
407 	int resid, linuxreclen;		/* Linux-format */
408 	caddr_t lbuf;			/* Linux-format */
409 	off_t base;
410 	struct l_dirent *linux_dirent;
411 	int buflen, error;
412 	size_t retval;
413 
414 	buflen = min(args->count, MAXBSIZE);
415 	buf = malloc(buflen, M_LINUX, M_WAITOK);
416 
417 	error = kern_getdirentries(td, args->fd, buf, buflen,
418 	    &base, NULL, UIO_SYSSPACE);
419 	if (error != 0) {
420 		error = linux_getdents_error(td, args->fd, error);
421 		goto out1;
422 	}
423 
424 	lbuf = malloc(LINUX_RECLEN(LINUX_NAME_MAX), M_LINUX, M_WAITOK | M_ZERO);
425 
426 	len = td->td_retval[0];
427 	inp = buf;
428 	outp = (caddr_t)args->dent;
429 	resid = args->count;
430 	retval = 0;
431 
432 	while (len > 0) {
433 		bdp = (struct dirent *) inp;
434 		reclen = bdp->d_reclen;
435 		linuxreclen = LINUX_RECLEN(bdp->d_namlen);
436 		/*
437 		 * No more space in the user supplied dirent buffer.
438 		 * Return EINVAL.
439 		 */
440 		if (resid < linuxreclen) {
441 			error = EINVAL;
442 			goto out;
443 		}
444 
445 		linux_dirent = (struct l_dirent*)lbuf;
446 		linux_dirent->d_ino = bdp->d_fileno;
447 		linux_dirent->d_off = bdp->d_off;
448 		linux_dirent->d_reclen = linuxreclen;
449 		/*
450 		 * Copy d_type to last byte of l_dirent buffer
451 		 */
452 		lbuf[linuxreclen - 1] = bdp->d_type;
453 		strlcpy(linux_dirent->d_name, bdp->d_name,
454 		    linuxreclen - offsetof(struct l_dirent, d_name)-1);
455 		error = copyout(linux_dirent, outp, linuxreclen);
456 		if (error != 0)
457 			goto out;
458 
459 		inp += reclen;
460 		base += reclen;
461 		len -= reclen;
462 
463 		retval += linuxreclen;
464 		outp += linuxreclen;
465 		resid -= linuxreclen;
466 	}
467 	td->td_retval[0] = retval;
468 
469 out:
470 	free(lbuf, M_LINUX);
471 out1:
472 	free(buf, M_LINUX);
473 	return (error);
474 }
475 #endif
476 
477 int
478 linux_getdents64(struct thread *td, struct linux_getdents64_args *args)
479 {
480 	struct dirent *bdp;
481 	caddr_t inp, buf;		/* BSD-format */
482 	int len, reclen;		/* BSD-format */
483 	caddr_t outp;			/* Linux-format */
484 	int resid, linuxreclen;		/* Linux-format */
485 	off_t base;
486 	struct l_dirent64 *linux_dirent64;
487 	int buflen, error;
488 	size_t retval;
489 
490 	buflen = min(args->count, MAXBSIZE);
491 	buf = malloc(buflen, M_LINUX, M_WAITOK);
492 
493 	error = kern_getdirentries(td, args->fd, buf, buflen,
494 	    &base, NULL, UIO_SYSSPACE);
495 	if (error != 0) {
496 		error = linux_getdents_error(td, args->fd, error);
497 		goto out1;
498 	}
499 
500 	linux_dirent64 = malloc(LINUX_RECLEN64(LINUX_NAME_MAX), M_LINUX,
501 	    M_WAITOK | M_ZERO);
502 
503 	len = td->td_retval[0];
504 	inp = buf;
505 	outp = (caddr_t)args->dirent;
506 	resid = args->count;
507 	retval = 0;
508 
509 	while (len > 0) {
510 		bdp = (struct dirent *) inp;
511 		reclen = bdp->d_reclen;
512 		linuxreclen = LINUX_RECLEN64(bdp->d_namlen);
513 		/*
514 		 * No more space in the user supplied dirent buffer.
515 		 * Return EINVAL.
516 		 */
517 		if (resid < linuxreclen) {
518 			error = EINVAL;
519 			goto out;
520 		}
521 
522 		linux_dirent64->d_ino = bdp->d_fileno;
523 		linux_dirent64->d_off = bdp->d_off;
524 		linux_dirent64->d_reclen = linuxreclen;
525 		linux_dirent64->d_type = bdp->d_type;
526 		strlcpy(linux_dirent64->d_name, bdp->d_name,
527 		    linuxreclen - offsetof(struct l_dirent64, d_name));
528 		error = copyout(linux_dirent64, outp, linuxreclen);
529 		if (error != 0)
530 			goto out;
531 
532 		inp += reclen;
533 		base += reclen;
534 		len -= reclen;
535 
536 		retval += linuxreclen;
537 		outp += linuxreclen;
538 		resid -= linuxreclen;
539 	}
540 	td->td_retval[0] = retval;
541 
542 out:
543 	free(linux_dirent64, M_LINUX);
544 out1:
545 	free(buf, M_LINUX);
546 	return (error);
547 }
548 
549 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
550 int
551 linux_readdir(struct thread *td, struct linux_readdir_args *args)
552 {
553 	struct dirent *bdp;
554 	caddr_t buf;			/* BSD-format */
555 	int linuxreclen;		/* Linux-format */
556 	off_t base;
557 	struct l_dirent *linux_dirent;	/* Linux-format */
558 	int buflen, error;
559 
560 	buflen = sizeof(*bdp);
561 	buf = malloc(buflen, M_LINUX, M_WAITOK);
562 
563 	error = kern_getdirentries(td, args->fd, buf, buflen,
564 	    &base, NULL, UIO_SYSSPACE);
565 	if (error != 0) {
566 		error = linux_getdents_error(td, args->fd, error);
567 		goto out;
568 	}
569 	if (td->td_retval[0] == 0)
570 		goto out;
571 
572 	linux_dirent = malloc(LINUX_RECLEN(LINUX_NAME_MAX), M_LINUX,
573 	    M_WAITOK | M_ZERO);
574 
575 	bdp = (struct dirent *) buf;
576 	linuxreclen = LINUX_RECLEN(bdp->d_namlen);
577 
578 	linux_dirent->d_ino = bdp->d_fileno;
579 	linux_dirent->d_off = bdp->d_off;
580 	linux_dirent->d_reclen = bdp->d_namlen;
581 	strlcpy(linux_dirent->d_name, bdp->d_name,
582 	    linuxreclen - offsetof(struct l_dirent, d_name));
583 	error = copyout(linux_dirent, args->dent, linuxreclen);
584 	if (error == 0)
585 		td->td_retval[0] = linuxreclen;
586 
587 	free(linux_dirent, M_LINUX);
588 out:
589 	free(buf, M_LINUX);
590 	return (error);
591 }
592 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
593 
594 /*
595  * These exist mainly for hooks for doing /compat/linux translation.
596  */
597 
598 #ifdef LINUX_LEGACY_SYSCALLS
599 int
600 linux_access(struct thread *td, struct linux_access_args *args)
601 {
602 
603 	/* Linux convention. */
604 	if (args->amode & ~(F_OK | X_OK | W_OK | R_OK))
605 		return (EINVAL);
606 
607 	return (kern_accessat(td, AT_FDCWD, args->path, UIO_USERSPACE, 0,
608 	    args->amode));
609 }
610 #endif
611 
612 static int
613 linux_do_accessat(struct thread *td, int ldfd, const char *filename,
614     int amode, int flags)
615 {
616 	int dfd;
617 
618 	/* Linux convention. */
619 	if (amode & ~(F_OK | X_OK | W_OK | R_OK))
620 		return (EINVAL);
621 
622 	dfd = (ldfd == LINUX_AT_FDCWD) ? AT_FDCWD : ldfd;
623 	return (kern_accessat(td, dfd, filename, UIO_USERSPACE, flags, amode));
624 }
625 
626 int
627 linux_faccessat(struct thread *td, struct linux_faccessat_args *args)
628 {
629 
630 	return (linux_do_accessat(td, args->dfd, args->filename, args->amode,
631 	    0));
632 }
633 
634 int
635 linux_faccessat2(struct thread *td, struct linux_faccessat2_args *args)
636 {
637 	int flags, unsupported;
638 
639 	/* XXX. AT_SYMLINK_NOFOLLOW is not supported by kern_accessat */
640 	unsupported = args->flags & ~(LINUX_AT_EACCESS | LINUX_AT_EMPTY_PATH);
641 	if (unsupported != 0) {
642 		linux_msg(td, "faccessat2 unsupported flag 0x%x", unsupported);
643 		return (EINVAL);
644 	}
645 
646 	flags = (args->flags & LINUX_AT_EACCESS) == 0 ? 0 :
647 	    AT_EACCESS;
648 	flags |= (args->flags & LINUX_AT_EMPTY_PATH) == 0 ? 0 :
649 	    AT_EMPTY_PATH;
650 	return (linux_do_accessat(td, args->dfd, args->filename, args->amode,
651 	    flags));
652 }
653 
654 
655 #ifdef LINUX_LEGACY_SYSCALLS
656 int
657 linux_unlink(struct thread *td, struct linux_unlink_args *args)
658 {
659 	int error;
660 	struct stat st;
661 
662 	error = kern_funlinkat(td, AT_FDCWD, args->path, FD_NONE,
663 	    UIO_USERSPACE, 0, 0);
664 	if (error == EPERM) {
665 		/* Introduce POSIX noncompliant behaviour of Linux */
666 		if (kern_statat(td, 0, AT_FDCWD, args->path,
667 		    UIO_USERSPACE, &st) == 0) {
668 			if (S_ISDIR(st.st_mode))
669 				error = EISDIR;
670 		}
671 	}
672 
673 	return (error);
674 }
675 #endif
676 
677 static int
678 linux_unlinkat_impl(struct thread *td, enum uio_seg pathseg, const char *path,
679     int dfd, struct linux_unlinkat_args *args)
680 {
681 	struct stat st;
682 	int error;
683 
684 	if (args->flag & LINUX_AT_REMOVEDIR)
685 		error = kern_frmdirat(td, dfd, path, FD_NONE, pathseg, 0);
686 	else
687 		error = kern_funlinkat(td, dfd, path, FD_NONE, pathseg, 0, 0);
688 	if (error == EPERM && !(args->flag & LINUX_AT_REMOVEDIR)) {
689 		/* Introduce POSIX noncompliant behaviour of Linux */
690 		if (kern_statat(td, AT_SYMLINK_NOFOLLOW, dfd, path,
691 		    pathseg, &st) == 0 && S_ISDIR(st.st_mode))
692 			error = EISDIR;
693 	}
694 	return (error);
695 }
696 
697 int
698 linux_unlinkat(struct thread *td, struct linux_unlinkat_args *args)
699 {
700 	int dfd;
701 
702 	if (args->flag & ~LINUX_AT_REMOVEDIR)
703 		return (EINVAL);
704 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
705 	return (linux_unlinkat_impl(td, UIO_USERSPACE, args->pathname,
706 	    dfd, args));
707 }
708 
709 int
710 linux_chdir(struct thread *td, struct linux_chdir_args *args)
711 {
712 
713 	return (kern_chdir(td, args->path, UIO_USERSPACE));
714 }
715 
716 #ifdef LINUX_LEGACY_SYSCALLS
717 int
718 linux_chmod(struct thread *td, struct linux_chmod_args *args)
719 {
720 
721 	return (kern_fchmodat(td, AT_FDCWD, args->path, UIO_USERSPACE,
722 	    args->mode, 0));
723 }
724 #endif
725 
726 int
727 linux_fchmodat(struct thread *td, struct linux_fchmodat_args *args)
728 {
729 	int dfd;
730 
731 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
732 	return (kern_fchmodat(td, dfd, args->filename, UIO_USERSPACE,
733 	    args->mode, 0));
734 }
735 
736 #ifdef LINUX_LEGACY_SYSCALLS
737 int
738 linux_mkdir(struct thread *td, struct linux_mkdir_args *args)
739 {
740 
741 	return (kern_mkdirat(td, AT_FDCWD, args->path, UIO_USERSPACE, args->mode));
742 }
743 #endif
744 
745 int
746 linux_mkdirat(struct thread *td, struct linux_mkdirat_args *args)
747 {
748 	int dfd;
749 
750 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
751 	return (kern_mkdirat(td, dfd, args->pathname, UIO_USERSPACE, args->mode));
752 }
753 
754 #ifdef LINUX_LEGACY_SYSCALLS
755 int
756 linux_rmdir(struct thread *td, struct linux_rmdir_args *args)
757 {
758 
759 	return (kern_frmdirat(td, AT_FDCWD, args->path, FD_NONE,
760 	    UIO_USERSPACE, 0));
761 }
762 
763 int
764 linux_rename(struct thread *td, struct linux_rename_args *args)
765 {
766 
767 	return (kern_renameat(td, AT_FDCWD, args->from, AT_FDCWD,
768 	    args->to, UIO_USERSPACE));
769 }
770 #endif
771 
772 int
773 linux_renameat(struct thread *td, struct linux_renameat_args *args)
774 {
775 	struct linux_renameat2_args renameat2_args = {
776 	    .olddfd = args->olddfd,
777 	    .oldname = args->oldname,
778 	    .newdfd = args->newdfd,
779 	    .newname = args->newname,
780 	    .flags = 0
781 	};
782 
783 	return (linux_renameat2(td, &renameat2_args));
784 }
785 
786 int
787 linux_renameat2(struct thread *td, struct linux_renameat2_args *args)
788 {
789 	int olddfd, newdfd;
790 
791 	if (args->flags != 0) {
792 		if (args->flags & ~(LINUX_RENAME_EXCHANGE |
793 		    LINUX_RENAME_NOREPLACE | LINUX_RENAME_WHITEOUT))
794 			return (EINVAL);
795 		if (args->flags & LINUX_RENAME_EXCHANGE &&
796 		    args->flags & (LINUX_RENAME_NOREPLACE |
797 		    LINUX_RENAME_WHITEOUT))
798 			return (EINVAL);
799 #if 0
800 		/*
801 		 * This spams the console on Ubuntu Focal.
802 		 *
803 		 * What's needed here is a general mechanism to let users know
804 		 * about missing features without hogging the system.
805 		 */
806 		linux_msg(td, "renameat2 unsupported flags 0x%x",
807 		    args->flags);
808 #endif
809 		return (EINVAL);
810 	}
811 
812 	olddfd = (args->olddfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->olddfd;
813 	newdfd = (args->newdfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->newdfd;
814 	return (kern_renameat(td, olddfd, args->oldname, newdfd,
815 	    args->newname, UIO_USERSPACE));
816 }
817 
818 #ifdef LINUX_LEGACY_SYSCALLS
819 int
820 linux_symlink(struct thread *td, struct linux_symlink_args *args)
821 {
822 
823 	return (kern_symlinkat(td, args->path, AT_FDCWD, args->to,
824 	    UIO_USERSPACE));
825 }
826 #endif
827 
828 int
829 linux_symlinkat(struct thread *td, struct linux_symlinkat_args *args)
830 {
831 	int dfd;
832 
833 	dfd = (args->newdfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->newdfd;
834 	return (kern_symlinkat(td, args->oldname, dfd, args->newname,
835 	    UIO_USERSPACE));
836 }
837 
838 #ifdef LINUX_LEGACY_SYSCALLS
839 int
840 linux_readlink(struct thread *td, struct linux_readlink_args *args)
841 {
842 
843 	if (args->count <= 0)
844 		return (EINVAL);
845 
846 	return (kern_readlinkat(td, AT_FDCWD, args->name, UIO_USERSPACE,
847 	    args->buf, UIO_USERSPACE, args->count));
848 }
849 #endif
850 
851 int
852 linux_readlinkat(struct thread *td, struct linux_readlinkat_args *args)
853 {
854 	int dfd;
855 
856 	if (args->bufsiz <= 0)
857 		return (EINVAL);
858 
859 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
860 	return (kern_readlinkat(td, dfd, args->path, UIO_USERSPACE,
861 	    args->buf, UIO_USERSPACE, args->bufsiz));
862 }
863 
864 int
865 linux_truncate(struct thread *td, struct linux_truncate_args *args)
866 {
867 
868 	return (kern_truncate(td, args->path, UIO_USERSPACE, args->length));
869 }
870 
871 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
872 int
873 linux_truncate64(struct thread *td, struct linux_truncate64_args *args)
874 {
875 	off_t length;
876 
877 #if defined(__amd64__) && defined(COMPAT_LINUX32)
878 	length = PAIR32TO64(off_t, args->length);
879 #else
880 	length = args->length;
881 #endif
882 
883 	return (kern_truncate(td, args->path, UIO_USERSPACE, length));
884 }
885 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
886 
887 int
888 linux_ftruncate(struct thread *td, struct linux_ftruncate_args *args)
889 {
890 
891 	return (kern_ftruncate(td, args->fd, args->length));
892 }
893 
894 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
895 int
896 linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
897 {
898 	off_t length;
899 
900 #if defined(__amd64__) && defined(COMPAT_LINUX32)
901 	length = PAIR32TO64(off_t, args->length);
902 #else
903 	length = args->length;
904 #endif
905 
906 	return (kern_ftruncate(td, args->fd, length));
907 }
908 #endif
909 
910 #ifdef LINUX_LEGACY_SYSCALLS
911 int
912 linux_link(struct thread *td, struct linux_link_args *args)
913 {
914 
915 	return (kern_linkat(td, AT_FDCWD, AT_FDCWD, args->path, args->to,
916 	    UIO_USERSPACE, AT_SYMLINK_FOLLOW));
917 }
918 #endif
919 
920 int
921 linux_linkat(struct thread *td, struct linux_linkat_args *args)
922 {
923 	int olddfd, newdfd, flag;
924 
925 	if (args->flag & ~(LINUX_AT_SYMLINK_FOLLOW | LINUX_AT_EMPTY_PATH))
926 		return (EINVAL);
927 
928 	flag = (args->flag & LINUX_AT_SYMLINK_FOLLOW) != 0 ? AT_SYMLINK_FOLLOW :
929 	    0;
930 	flag |= (args->flag & LINUX_AT_EMPTY_PATH) != 0 ? AT_EMPTY_PATH : 0;
931 
932 	olddfd = (args->olddfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->olddfd;
933 	newdfd = (args->newdfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->newdfd;
934 	return (kern_linkat(td, olddfd, newdfd, args->oldname,
935 	    args->newname, UIO_USERSPACE, flag));
936 }
937 
938 int
939 linux_fdatasync(struct thread *td, struct linux_fdatasync_args *uap)
940 {
941 
942 	return (kern_fsync(td, uap->fd, false));
943 }
944 
945 int
946 linux_sync_file_range(struct thread *td, struct linux_sync_file_range_args *uap)
947 {
948 	off_t nbytes, offset;
949 
950 #if defined(__amd64__) && defined(COMPAT_LINUX32)
951 	nbytes = PAIR32TO64(off_t, uap->nbytes);
952 	offset = PAIR32TO64(off_t, uap->offset);
953 #else
954 	nbytes = uap->nbytes;
955 	offset = uap->offset;
956 #endif
957 
958 	if (offset < 0 || nbytes < 0 ||
959 	    (uap->flags & ~(LINUX_SYNC_FILE_RANGE_WAIT_BEFORE |
960 	    LINUX_SYNC_FILE_RANGE_WRITE |
961 	    LINUX_SYNC_FILE_RANGE_WAIT_AFTER)) != 0) {
962 		return (EINVAL);
963 	}
964 
965 	return (kern_fsync(td, uap->fd, false));
966 }
967 
968 int
969 linux_pread(struct thread *td, struct linux_pread_args *uap)
970 {
971 	struct vnode *vp;
972 	off_t offset;
973 	int error;
974 
975 #if defined(__amd64__) && defined(COMPAT_LINUX32)
976 	offset = PAIR32TO64(off_t, uap->offset);
977 #else
978 	offset = uap->offset;
979 #endif
980 
981 	error = kern_pread(td, uap->fd, uap->buf, uap->nbyte, offset);
982 	if (error == 0) {
983 		/* This seems to violate POSIX but Linux does it. */
984 		error = fgetvp(td, uap->fd, &cap_pread_rights, &vp);
985 		if (error != 0)
986 			return (error);
987 		if (vp->v_type == VDIR)
988 			error = EISDIR;
989 		vrele(vp);
990 	}
991 	return (error);
992 }
993 
994 int
995 linux_pwrite(struct thread *td, struct linux_pwrite_args *uap)
996 {
997 	off_t offset;
998 
999 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1000 	offset = PAIR32TO64(off_t, uap->offset);
1001 #else
1002 	offset = uap->offset;
1003 #endif
1004 
1005 	return (linux_enobufs2eagain(td, uap->fd,
1006 	    kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, offset)));
1007 }
1008 
1009 #define HALF_LONG_BITS ((sizeof(l_long) * NBBY / 2))
1010 
1011 static inline off_t
1012 pos_from_hilo(unsigned long high, unsigned long low)
1013 {
1014 
1015 	return (((off_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low;
1016 }
1017 
1018 int
1019 linux_preadv(struct thread *td, struct linux_preadv_args *uap)
1020 {
1021 	struct uio *auio;
1022 	int error;
1023 	off_t offset;
1024 
1025 	/*
1026 	 * According http://man7.org/linux/man-pages/man2/preadv.2.html#NOTES
1027 	 * pos_l and pos_h, respectively, contain the
1028 	 * low order and high order 32 bits of offset.
1029 	 */
1030 	offset = pos_from_hilo(uap->pos_h, uap->pos_l);
1031 	if (offset < 0)
1032 		return (EINVAL);
1033 #ifdef COMPAT_LINUX32
1034 	error = freebsd32_copyinuio(PTRIN(uap->vec), uap->vlen, &auio);
1035 #else
1036 	error = copyinuio(uap->vec, uap->vlen, &auio);
1037 #endif
1038 	if (error != 0)
1039 		return (error);
1040 	error = kern_preadv(td, uap->fd, auio, offset);
1041 	free(auio, M_IOV);
1042 	return (error);
1043 }
1044 
1045 int
1046 linux_pwritev(struct thread *td, struct linux_pwritev_args *uap)
1047 {
1048 	struct uio *auio;
1049 	int error;
1050 	off_t offset;
1051 
1052 	/*
1053 	 * According http://man7.org/linux/man-pages/man2/pwritev.2.html#NOTES
1054 	 * pos_l and pos_h, respectively, contain the
1055 	 * low order and high order 32 bits of offset.
1056 	 */
1057 	offset = pos_from_hilo(uap->pos_h, uap->pos_l);
1058 	if (offset < 0)
1059 		return (EINVAL);
1060 #ifdef COMPAT_LINUX32
1061 	error = freebsd32_copyinuio(PTRIN(uap->vec), uap->vlen, &auio);
1062 #else
1063 	error = copyinuio(uap->vec, uap->vlen, &auio);
1064 #endif
1065 	if (error != 0)
1066 		return (error);
1067 	error = kern_pwritev(td, uap->fd, auio, offset);
1068 	free(auio, M_IOV);
1069 	return (linux_enobufs2eagain(td, uap->fd, error));
1070 }
1071 
1072 int
1073 linux_mount(struct thread *td, struct linux_mount_args *args)
1074 {
1075 	struct mntarg *ma = NULL;
1076 	char *fstypename, *mntonname, *mntfromname, *data;
1077 	int error, fsflags;
1078 
1079 	fstypename = malloc(MNAMELEN, M_TEMP, M_WAITOK);
1080 	mntonname = malloc(MNAMELEN, M_TEMP, M_WAITOK);
1081 	mntfromname = malloc(MNAMELEN, M_TEMP, M_WAITOK);
1082 	data = NULL;
1083 	error = copyinstr(args->filesystemtype, fstypename, MNAMELEN - 1,
1084 	    NULL);
1085 	if (error != 0)
1086 		goto out;
1087 	if (args->specialfile != NULL) {
1088 		error = copyinstr(args->specialfile, mntfromname, MNAMELEN - 1, NULL);
1089 		if (error != 0)
1090 			goto out;
1091 	} else {
1092 		mntfromname[0] = '\0';
1093 	}
1094 	error = copyinstr(args->dir, mntonname, MNAMELEN - 1, NULL);
1095 	if (error != 0)
1096 		goto out;
1097 
1098 	if (strcmp(fstypename, "ext2") == 0) {
1099 		strcpy(fstypename, "ext2fs");
1100 	} else if (strcmp(fstypename, "proc") == 0) {
1101 		strcpy(fstypename, "linprocfs");
1102 	} else if (strcmp(fstypename, "vfat") == 0) {
1103 		strcpy(fstypename, "msdosfs");
1104 	} else if (strcmp(fstypename, "fuse") == 0 ||
1105 	    strncmp(fstypename, "fuse.", 5) == 0) {
1106 		char *fuse_options, *fuse_option, *fuse_name;
1107 
1108 		strcpy(mntfromname, "/dev/fuse");
1109 		strcpy(fstypename, "fusefs");
1110 		data = malloc(MNAMELEN, M_TEMP, M_WAITOK);
1111 		error = copyinstr(args->data, data, MNAMELEN - 1, NULL);
1112 		if (error != 0)
1113 			goto out;
1114 
1115 		fuse_options = data;
1116 		while ((fuse_option = strsep(&fuse_options, ",")) != NULL) {
1117 			fuse_name = strsep(&fuse_option, "=");
1118 			if (fuse_name == NULL || fuse_option == NULL)
1119 				goto out;
1120 			ma = mount_arg(ma, fuse_name, fuse_option, -1);
1121 		}
1122 
1123 		/*
1124 		 * The FUSE server uses Linux errno values instead of FreeBSD
1125 		 * ones; add a flag to tell fuse(4) to do errno translation.
1126 		 */
1127 		ma = mount_arg(ma, "linux_errnos", "1", -1);
1128 	}
1129 
1130 	fsflags = 0;
1131 
1132 	/*
1133 	 * Linux SYNC flag is not included; the closest equivalent
1134 	 * FreeBSD has is !ASYNC, which is our default.
1135 	 */
1136 	if (args->rwflag & LINUX_MS_RDONLY)
1137 		fsflags |= MNT_RDONLY;
1138 	if (args->rwflag & LINUX_MS_NOSUID)
1139 		fsflags |= MNT_NOSUID;
1140 	if (args->rwflag & LINUX_MS_NOEXEC)
1141 		fsflags |= MNT_NOEXEC;
1142 	if (args->rwflag & LINUX_MS_REMOUNT)
1143 		fsflags |= MNT_UPDATE;
1144 
1145 	ma = mount_arg(ma, "fstype", fstypename, -1);
1146 	ma = mount_arg(ma, "fspath", mntonname, -1);
1147 	ma = mount_arg(ma, "from", mntfromname, -1);
1148 	error = kernel_mount(ma, fsflags);
1149 out:
1150 	free(fstypename, M_TEMP);
1151 	free(mntonname, M_TEMP);
1152 	free(mntfromname, M_TEMP);
1153 	free(data, M_TEMP);
1154 	return (error);
1155 }
1156 
1157 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
1158 int
1159 linux_oldumount(struct thread *td, struct linux_oldumount_args *args)
1160 {
1161 
1162 	return (kern_unmount(td, args->path, 0));
1163 }
1164 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
1165 
1166 #ifdef LINUX_LEGACY_SYSCALLS
1167 int
1168 linux_umount(struct thread *td, struct linux_umount_args *args)
1169 {
1170 	int flags;
1171 
1172 	flags = 0;
1173 	if ((args->flags & LINUX_MNT_FORCE) != 0) {
1174 		args->flags &= ~LINUX_MNT_FORCE;
1175 		flags |= MNT_FORCE;
1176 	}
1177 	if (args->flags != 0) {
1178 		linux_msg(td, "unsupported umount2 flags %#x", args->flags);
1179 		return (EINVAL);
1180 	}
1181 
1182 	return (kern_unmount(td, args->path, flags));
1183 }
1184 #endif
1185 
1186 /*
1187  * fcntl family of syscalls
1188  */
1189 
1190 struct l_flock {
1191 	l_short		l_type;
1192 	l_short		l_whence;
1193 	l_off_t		l_start;
1194 	l_off_t		l_len;
1195 	l_pid_t		l_pid;
1196 }
1197 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1198 __packed
1199 #endif
1200 ;
1201 
1202 static void
1203 linux_to_bsd_flock(struct l_flock *linux_flock, struct flock *bsd_flock)
1204 {
1205 	switch (linux_flock->l_type) {
1206 	case LINUX_F_RDLCK:
1207 		bsd_flock->l_type = F_RDLCK;
1208 		break;
1209 	case LINUX_F_WRLCK:
1210 		bsd_flock->l_type = F_WRLCK;
1211 		break;
1212 	case LINUX_F_UNLCK:
1213 		bsd_flock->l_type = F_UNLCK;
1214 		break;
1215 	default:
1216 		bsd_flock->l_type = -1;
1217 		break;
1218 	}
1219 	bsd_flock->l_whence = linux_flock->l_whence;
1220 	bsd_flock->l_start = (off_t)linux_flock->l_start;
1221 	bsd_flock->l_len = (off_t)linux_flock->l_len;
1222 	bsd_flock->l_pid = (pid_t)linux_flock->l_pid;
1223 	bsd_flock->l_sysid = 0;
1224 }
1225 
1226 static void
1227 bsd_to_linux_flock(struct flock *bsd_flock, struct l_flock *linux_flock)
1228 {
1229 	switch (bsd_flock->l_type) {
1230 	case F_RDLCK:
1231 		linux_flock->l_type = LINUX_F_RDLCK;
1232 		break;
1233 	case F_WRLCK:
1234 		linux_flock->l_type = LINUX_F_WRLCK;
1235 		break;
1236 	case F_UNLCK:
1237 		linux_flock->l_type = LINUX_F_UNLCK;
1238 		break;
1239 	}
1240 	linux_flock->l_whence = bsd_flock->l_whence;
1241 	linux_flock->l_start = (l_off_t)bsd_flock->l_start;
1242 	linux_flock->l_len = (l_off_t)bsd_flock->l_len;
1243 	linux_flock->l_pid = (l_pid_t)bsd_flock->l_pid;
1244 }
1245 
1246 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
1247 struct l_flock64 {
1248 	l_short		l_type;
1249 	l_short		l_whence;
1250 	l_loff_t	l_start;
1251 	l_loff_t	l_len;
1252 	l_pid_t		l_pid;
1253 }
1254 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1255 __packed
1256 #endif
1257 ;
1258 
1259 static void
1260 linux_to_bsd_flock64(struct l_flock64 *linux_flock, struct flock *bsd_flock)
1261 {
1262 	switch (linux_flock->l_type) {
1263 	case LINUX_F_RDLCK:
1264 		bsd_flock->l_type = F_RDLCK;
1265 		break;
1266 	case LINUX_F_WRLCK:
1267 		bsd_flock->l_type = F_WRLCK;
1268 		break;
1269 	case LINUX_F_UNLCK:
1270 		bsd_flock->l_type = F_UNLCK;
1271 		break;
1272 	default:
1273 		bsd_flock->l_type = -1;
1274 		break;
1275 	}
1276 	bsd_flock->l_whence = linux_flock->l_whence;
1277 	bsd_flock->l_start = (off_t)linux_flock->l_start;
1278 	bsd_flock->l_len = (off_t)linux_flock->l_len;
1279 	bsd_flock->l_pid = (pid_t)linux_flock->l_pid;
1280 	bsd_flock->l_sysid = 0;
1281 }
1282 
1283 static void
1284 bsd_to_linux_flock64(struct flock *bsd_flock, struct l_flock64 *linux_flock)
1285 {
1286 	switch (bsd_flock->l_type) {
1287 	case F_RDLCK:
1288 		linux_flock->l_type = LINUX_F_RDLCK;
1289 		break;
1290 	case F_WRLCK:
1291 		linux_flock->l_type = LINUX_F_WRLCK;
1292 		break;
1293 	case F_UNLCK:
1294 		linux_flock->l_type = LINUX_F_UNLCK;
1295 		break;
1296 	}
1297 	linux_flock->l_whence = bsd_flock->l_whence;
1298 	linux_flock->l_start = (l_loff_t)bsd_flock->l_start;
1299 	linux_flock->l_len = (l_loff_t)bsd_flock->l_len;
1300 	linux_flock->l_pid = (l_pid_t)bsd_flock->l_pid;
1301 }
1302 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
1303 
1304 static int
1305 fcntl_common(struct thread *td, struct linux_fcntl_args *args)
1306 {
1307 	struct l_flock linux_flock;
1308 	struct flock bsd_flock;
1309 	struct pipe *fpipe;
1310 	struct file *fp;
1311 	long arg;
1312 	int error, result;
1313 
1314 	switch (args->cmd) {
1315 	case LINUX_F_DUPFD:
1316 		return (kern_fcntl(td, args->fd, F_DUPFD, args->arg));
1317 
1318 	case LINUX_F_GETFD:
1319 		return (kern_fcntl(td, args->fd, F_GETFD, 0));
1320 
1321 	case LINUX_F_SETFD:
1322 		return (kern_fcntl(td, args->fd, F_SETFD, args->arg));
1323 
1324 	case LINUX_F_GETFL:
1325 		error = kern_fcntl(td, args->fd, F_GETFL, 0);
1326 		result = td->td_retval[0];
1327 		td->td_retval[0] = 0;
1328 		if (result & O_RDONLY)
1329 			td->td_retval[0] |= LINUX_O_RDONLY;
1330 		if (result & O_WRONLY)
1331 			td->td_retval[0] |= LINUX_O_WRONLY;
1332 		if (result & O_RDWR)
1333 			td->td_retval[0] |= LINUX_O_RDWR;
1334 		if (result & O_NDELAY)
1335 			td->td_retval[0] |= LINUX_O_NONBLOCK;
1336 		if (result & O_APPEND)
1337 			td->td_retval[0] |= LINUX_O_APPEND;
1338 		if (result & O_FSYNC)
1339 			td->td_retval[0] |= LINUX_O_SYNC;
1340 		if (result & O_ASYNC)
1341 			td->td_retval[0] |= LINUX_O_ASYNC;
1342 #ifdef LINUX_O_NOFOLLOW
1343 		if (result & O_NOFOLLOW)
1344 			td->td_retval[0] |= LINUX_O_NOFOLLOW;
1345 #endif
1346 #ifdef LINUX_O_DIRECT
1347 		if (result & O_DIRECT)
1348 			td->td_retval[0] |= LINUX_O_DIRECT;
1349 #endif
1350 		return (error);
1351 
1352 	case LINUX_F_SETFL:
1353 		arg = 0;
1354 		if (args->arg & LINUX_O_NDELAY)
1355 			arg |= O_NONBLOCK;
1356 		if (args->arg & LINUX_O_APPEND)
1357 			arg |= O_APPEND;
1358 		if (args->arg & LINUX_O_SYNC)
1359 			arg |= O_FSYNC;
1360 		if (args->arg & LINUX_O_ASYNC)
1361 			arg |= O_ASYNC;
1362 #ifdef LINUX_O_NOFOLLOW
1363 		if (args->arg & LINUX_O_NOFOLLOW)
1364 			arg |= O_NOFOLLOW;
1365 #endif
1366 #ifdef LINUX_O_DIRECT
1367 		if (args->arg & LINUX_O_DIRECT)
1368 			arg |= O_DIRECT;
1369 #endif
1370 		return (kern_fcntl(td, args->fd, F_SETFL, arg));
1371 
1372 	case LINUX_F_GETLK:
1373 		error = copyin((void *)args->arg, &linux_flock,
1374 		    sizeof(linux_flock));
1375 		if (error)
1376 			return (error);
1377 		linux_to_bsd_flock(&linux_flock, &bsd_flock);
1378 		error = kern_fcntl(td, args->fd, F_GETLK, (intptr_t)&bsd_flock);
1379 		if (error)
1380 			return (error);
1381 		bsd_to_linux_flock(&bsd_flock, &linux_flock);
1382 		return (copyout(&linux_flock, (void *)args->arg,
1383 		    sizeof(linux_flock)));
1384 
1385 	case LINUX_F_SETLK:
1386 		error = copyin((void *)args->arg, &linux_flock,
1387 		    sizeof(linux_flock));
1388 		if (error)
1389 			return (error);
1390 		linux_to_bsd_flock(&linux_flock, &bsd_flock);
1391 		return (kern_fcntl(td, args->fd, F_SETLK,
1392 		    (intptr_t)&bsd_flock));
1393 
1394 	case LINUX_F_SETLKW:
1395 		error = copyin((void *)args->arg, &linux_flock,
1396 		    sizeof(linux_flock));
1397 		if (error)
1398 			return (error);
1399 		linux_to_bsd_flock(&linux_flock, &bsd_flock);
1400 		return (kern_fcntl(td, args->fd, F_SETLKW,
1401 		     (intptr_t)&bsd_flock));
1402 
1403 	case LINUX_F_GETOWN:
1404 		return (kern_fcntl(td, args->fd, F_GETOWN, 0));
1405 
1406 	case LINUX_F_SETOWN:
1407 		/*
1408 		 * XXX some Linux applications depend on F_SETOWN having no
1409 		 * significant effect for pipes (SIGIO is not delivered for
1410 		 * pipes under Linux-2.2.35 at least).
1411 		 */
1412 		error = fget(td, args->fd,
1413 		    &cap_fcntl_rights, &fp);
1414 		if (error)
1415 			return (error);
1416 		if (fp->f_type == DTYPE_PIPE) {
1417 			fdrop(fp, td);
1418 			return (EINVAL);
1419 		}
1420 		fdrop(fp, td);
1421 
1422 		return (kern_fcntl(td, args->fd, F_SETOWN, args->arg));
1423 
1424 	case LINUX_F_DUPFD_CLOEXEC:
1425 		return (kern_fcntl(td, args->fd, F_DUPFD_CLOEXEC, args->arg));
1426 	/*
1427 	 * Our F_SEAL_* values match Linux one for maximum compatibility.  So we
1428 	 * only needed to account for different values for fcntl(2) commands.
1429 	 */
1430 	case LINUX_F_GET_SEALS:
1431 		error = kern_fcntl(td, args->fd, F_GET_SEALS, 0);
1432 		if (error != 0)
1433 			return (error);
1434 		td->td_retval[0] = bsd_to_linux_bits(td->td_retval[0],
1435 		    seal_bitmap, 0);
1436 		return (0);
1437 
1438 	case LINUX_F_ADD_SEALS:
1439 		return (kern_fcntl(td, args->fd, F_ADD_SEALS,
1440 		    linux_to_bsd_bits(args->arg, seal_bitmap, 0)));
1441 
1442 	case LINUX_F_GETPIPE_SZ:
1443 		error = fget(td, args->fd,
1444 		    &cap_fcntl_rights, &fp);
1445 		if (error != 0)
1446 			return (error);
1447 		if (fp->f_type != DTYPE_PIPE) {
1448 			fdrop(fp, td);
1449 			return (EINVAL);
1450 		}
1451 		fpipe = fp->f_data;
1452 		td->td_retval[0] = fpipe->pipe_buffer.size;
1453 		fdrop(fp, td);
1454 		return (0);
1455 
1456 	default:
1457 		linux_msg(td, "unsupported fcntl cmd %d", args->cmd);
1458 		return (EINVAL);
1459 	}
1460 }
1461 
1462 int
1463 linux_fcntl(struct thread *td, struct linux_fcntl_args *args)
1464 {
1465 
1466 	return (fcntl_common(td, args));
1467 }
1468 
1469 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
1470 int
1471 linux_fcntl64(struct thread *td, struct linux_fcntl64_args *args)
1472 {
1473 	struct l_flock64 linux_flock;
1474 	struct flock bsd_flock;
1475 	struct linux_fcntl_args fcntl_args;
1476 	int error;
1477 
1478 	switch (args->cmd) {
1479 	case LINUX_F_GETLK64:
1480 		error = copyin((void *)args->arg, &linux_flock,
1481 		    sizeof(linux_flock));
1482 		if (error)
1483 			return (error);
1484 		linux_to_bsd_flock64(&linux_flock, &bsd_flock);
1485 		error = kern_fcntl(td, args->fd, F_GETLK, (intptr_t)&bsd_flock);
1486 		if (error)
1487 			return (error);
1488 		bsd_to_linux_flock64(&bsd_flock, &linux_flock);
1489 		return (copyout(&linux_flock, (void *)args->arg,
1490 			    sizeof(linux_flock)));
1491 
1492 	case LINUX_F_SETLK64:
1493 		error = copyin((void *)args->arg, &linux_flock,
1494 		    sizeof(linux_flock));
1495 		if (error)
1496 			return (error);
1497 		linux_to_bsd_flock64(&linux_flock, &bsd_flock);
1498 		return (kern_fcntl(td, args->fd, F_SETLK,
1499 		    (intptr_t)&bsd_flock));
1500 
1501 	case LINUX_F_SETLKW64:
1502 		error = copyin((void *)args->arg, &linux_flock,
1503 		    sizeof(linux_flock));
1504 		if (error)
1505 			return (error);
1506 		linux_to_bsd_flock64(&linux_flock, &bsd_flock);
1507 		return (kern_fcntl(td, args->fd, F_SETLKW,
1508 		    (intptr_t)&bsd_flock));
1509 	}
1510 
1511 	fcntl_args.fd = args->fd;
1512 	fcntl_args.cmd = args->cmd;
1513 	fcntl_args.arg = args->arg;
1514 	return (fcntl_common(td, &fcntl_args));
1515 }
1516 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
1517 
1518 #ifdef LINUX_LEGACY_SYSCALLS
1519 int
1520 linux_chown(struct thread *td, struct linux_chown_args *args)
1521 {
1522 
1523 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE,
1524 	    args->uid, args->gid, 0));
1525 }
1526 #endif
1527 
1528 int
1529 linux_fchownat(struct thread *td, struct linux_fchownat_args *args)
1530 {
1531 	int dfd, flag, unsupported;
1532 
1533 	unsupported = args->flag & ~(LINUX_AT_SYMLINK_NOFOLLOW | LINUX_AT_EMPTY_PATH);
1534 	if (unsupported != 0) {
1535 		linux_msg(td, "fchownat unsupported flag 0x%x", unsupported);
1536 		return (EINVAL);
1537 	}
1538 
1539 	flag = (args->flag & LINUX_AT_SYMLINK_NOFOLLOW) == 0 ? 0 :
1540 	    AT_SYMLINK_NOFOLLOW;
1541 	flag |= (args->flag & LINUX_AT_EMPTY_PATH) == 0 ? 0 :
1542 	    AT_EMPTY_PATH;
1543 
1544 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD :  args->dfd;
1545 	return (kern_fchownat(td, dfd, args->filename, UIO_USERSPACE,
1546 	    args->uid, args->gid, flag));
1547 }
1548 
1549 #ifdef LINUX_LEGACY_SYSCALLS
1550 int
1551 linux_lchown(struct thread *td, struct linux_lchown_args *args)
1552 {
1553 
1554 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE, args->uid,
1555 	    args->gid, AT_SYMLINK_NOFOLLOW));
1556 }
1557 #endif
1558 
1559 static int
1560 convert_fadvice(int advice)
1561 {
1562 	switch (advice) {
1563 	case LINUX_POSIX_FADV_NORMAL:
1564 		return (POSIX_FADV_NORMAL);
1565 	case LINUX_POSIX_FADV_RANDOM:
1566 		return (POSIX_FADV_RANDOM);
1567 	case LINUX_POSIX_FADV_SEQUENTIAL:
1568 		return (POSIX_FADV_SEQUENTIAL);
1569 	case LINUX_POSIX_FADV_WILLNEED:
1570 		return (POSIX_FADV_WILLNEED);
1571 	case LINUX_POSIX_FADV_DONTNEED:
1572 		return (POSIX_FADV_DONTNEED);
1573 	case LINUX_POSIX_FADV_NOREUSE:
1574 		return (POSIX_FADV_NOREUSE);
1575 	default:
1576 		return (-1);
1577 	}
1578 }
1579 
1580 int
1581 linux_fadvise64(struct thread *td, struct linux_fadvise64_args *args)
1582 {
1583 	off_t offset;
1584 	int advice;
1585 
1586 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1587 	offset = PAIR32TO64(off_t, args->offset);
1588 #else
1589 	offset = args->offset;
1590 #endif
1591 
1592 	advice = convert_fadvice(args->advice);
1593 	if (advice == -1)
1594 		return (EINVAL);
1595 	return (kern_posix_fadvise(td, args->fd, offset, args->len, advice));
1596 }
1597 
1598 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
1599 int
1600 linux_fadvise64_64(struct thread *td, struct linux_fadvise64_64_args *args)
1601 {
1602 	off_t len, offset;
1603 	int advice;
1604 
1605 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1606 	len = PAIR32TO64(off_t, args->len);
1607 	offset = PAIR32TO64(off_t, args->offset);
1608 #else
1609 	len = args->len;
1610 	offset = args->offset;
1611 #endif
1612 
1613 	advice = convert_fadvice(args->advice);
1614 	if (advice == -1)
1615 		return (EINVAL);
1616 	return (kern_posix_fadvise(td, args->fd, offset, len, advice));
1617 }
1618 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
1619 
1620 #ifdef LINUX_LEGACY_SYSCALLS
1621 int
1622 linux_pipe(struct thread *td, struct linux_pipe_args *args)
1623 {
1624 	int fildes[2];
1625 	int error;
1626 
1627 	error = kern_pipe(td, fildes, 0, NULL, NULL);
1628 	if (error != 0)
1629 		return (error);
1630 
1631 	error = copyout(fildes, args->pipefds, sizeof(fildes));
1632 	if (error != 0) {
1633 		(void)kern_close(td, fildes[0]);
1634 		(void)kern_close(td, fildes[1]);
1635 	}
1636 
1637 	return (error);
1638 }
1639 #endif
1640 
1641 int
1642 linux_pipe2(struct thread *td, struct linux_pipe2_args *args)
1643 {
1644 	int fildes[2];
1645 	int error, flags;
1646 
1647 	if ((args->flags & ~(LINUX_O_NONBLOCK | LINUX_O_CLOEXEC)) != 0)
1648 		return (EINVAL);
1649 
1650 	flags = 0;
1651 	if ((args->flags & LINUX_O_NONBLOCK) != 0)
1652 		flags |= O_NONBLOCK;
1653 	if ((args->flags & LINUX_O_CLOEXEC) != 0)
1654 		flags |= O_CLOEXEC;
1655 	error = kern_pipe(td, fildes, flags, NULL, NULL);
1656 	if (error != 0)
1657 		return (error);
1658 
1659 	error = copyout(fildes, args->pipefds, sizeof(fildes));
1660 	if (error != 0) {
1661 		(void)kern_close(td, fildes[0]);
1662 		(void)kern_close(td, fildes[1]);
1663 	}
1664 
1665 	return (error);
1666 }
1667 
1668 int
1669 linux_dup3(struct thread *td, struct linux_dup3_args *args)
1670 {
1671 	int cmd;
1672 	intptr_t newfd;
1673 
1674 	if (args->oldfd == args->newfd)
1675 		return (EINVAL);
1676 	if ((args->flags & ~LINUX_O_CLOEXEC) != 0)
1677 		return (EINVAL);
1678 	if (args->flags & LINUX_O_CLOEXEC)
1679 		cmd = F_DUP2FD_CLOEXEC;
1680 	else
1681 		cmd = F_DUP2FD;
1682 
1683 	newfd = args->newfd;
1684 	return (kern_fcntl(td, args->oldfd, cmd, newfd));
1685 }
1686 
1687 int
1688 linux_fallocate(struct thread *td, struct linux_fallocate_args *args)
1689 {
1690 	off_t len, offset;
1691 
1692 	/*
1693 	 * We emulate only posix_fallocate system call for which
1694 	 * mode should be 0.
1695 	 */
1696 	if (args->mode != 0)
1697 		return (EOPNOTSUPP);
1698 
1699 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1700 	len = PAIR32TO64(off_t, args->len);
1701 	offset = PAIR32TO64(off_t, args->offset);
1702 #else
1703 	len = args->len;
1704 	offset = args->offset;
1705 #endif
1706 
1707 	return (kern_posix_fallocate(td, args->fd, offset, len));
1708 }
1709 
1710 int
1711 linux_copy_file_range(struct thread *td, struct linux_copy_file_range_args
1712     *args)
1713 {
1714 	l_loff_t inoff, outoff, *inoffp, *outoffp;
1715 	int error, flags;
1716 
1717 	/*
1718 	 * copy_file_range(2) on Linux doesn't define any flags (yet), so is
1719 	 * the native implementation.  Enforce it.
1720 	 */
1721 	if (args->flags != 0) {
1722 		linux_msg(td, "copy_file_range unsupported flags 0x%x",
1723 		    args->flags);
1724 		return (EINVAL);
1725 	}
1726 	flags = 0;
1727 	inoffp = outoffp = NULL;
1728 	if (args->off_in != NULL) {
1729 		error = copyin(args->off_in, &inoff, sizeof(l_loff_t));
1730 		if (error != 0)
1731 			return (error);
1732 		inoffp = &inoff;
1733 	}
1734 	if (args->off_out != NULL) {
1735 		error = copyin(args->off_out, &outoff, sizeof(l_loff_t));
1736 		if (error != 0)
1737 			return (error);
1738 		outoffp = &outoff;
1739 	}
1740 
1741 	error = kern_copy_file_range(td, args->fd_in, inoffp, args->fd_out,
1742 	    outoffp, args->len, flags);
1743 	if (error == 0 && args->off_in != NULL)
1744 		error = copyout(inoffp, args->off_in, sizeof(l_loff_t));
1745 	if (error == 0 && args->off_out != NULL)
1746 		error = copyout(outoffp, args->off_out, sizeof(l_loff_t));
1747 	return (error);
1748 }
1749 
1750 #define	LINUX_MEMFD_PREFIX	"memfd:"
1751 
1752 int
1753 linux_memfd_create(struct thread *td, struct linux_memfd_create_args *args)
1754 {
1755 	char memfd_name[LINUX_NAME_MAX + 1];
1756 	int error, flags, shmflags, oflags;
1757 
1758 	/*
1759 	 * This is our clever trick to avoid the heap allocation to copy in the
1760 	 * uname.  We don't really need to go this far out of our way, but it
1761 	 * does keep the rest of this function fairly clean as they don't have
1762 	 * to worry about cleanup on the way out.
1763 	 */
1764 	error = copyinstr(args->uname_ptr,
1765 	    memfd_name + sizeof(LINUX_MEMFD_PREFIX) - 1,
1766 	    LINUX_NAME_MAX - sizeof(LINUX_MEMFD_PREFIX) - 1, NULL);
1767 	if (error != 0) {
1768 		if (error == ENAMETOOLONG)
1769 			error = EINVAL;
1770 		return (error);
1771 	}
1772 
1773 	memcpy(memfd_name, LINUX_MEMFD_PREFIX, sizeof(LINUX_MEMFD_PREFIX) - 1);
1774 	flags = linux_to_bsd_bits(args->flags, mfd_bitmap, 0);
1775 	if ((flags & ~(MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB |
1776 	    MFD_HUGE_MASK)) != 0)
1777 		return (EINVAL);
1778 	/* Size specified but no HUGETLB. */
1779 	if ((flags & MFD_HUGE_MASK) != 0 && (flags & MFD_HUGETLB) == 0)
1780 		return (EINVAL);
1781 	/* We don't actually support HUGETLB. */
1782 	if ((flags & MFD_HUGETLB) != 0)
1783 		return (ENOSYS);
1784 	oflags = O_RDWR;
1785 	shmflags = SHM_GROW_ON_WRITE;
1786 	if ((flags & MFD_CLOEXEC) != 0)
1787 		oflags |= O_CLOEXEC;
1788 	if ((flags & MFD_ALLOW_SEALING) != 0)
1789 		shmflags |= SHM_ALLOW_SEALING;
1790 	return (kern_shm_open2(td, SHM_ANON, oflags, 0, shmflags, NULL,
1791 	    memfd_name));
1792 }
1793 
1794 int
1795 linux_splice(struct thread *td, struct linux_splice_args *args)
1796 {
1797 
1798 	linux_msg(td, "syscall splice not really implemented");
1799 
1800 	/*
1801 	 * splice(2) is documented to return EINVAL in various circumstances;
1802 	 * returning it instead of ENOSYS should hint the caller to use fallback
1803 	 * instead.
1804 	 */
1805 	return (EINVAL);
1806 }
1807 
1808 int
1809 linux_close_range(struct thread *td, struct linux_close_range_args *args)
1810 {
1811 	u_int flags = 0;
1812 
1813 	/*
1814 	 * Implementing close_range(CLOSE_RANGE_UNSHARE) allows Linux to
1815 	 * unshare filedesc table of the calling thread from others threads
1816 	 * in a thread group (i.e., process in the FreeBSD) or others processes,
1817 	 * which shares the same table, before closing the files. FreeBSD does
1818 	 * not have compatible unsharing mechanism due to the fact that sharing
1819 	 * process resources, including filedesc table, is at thread level in the
1820 	 * Linux, while in the FreeBSD it is at the process level.
1821 	 * Return EINVAL for now if the CLOSE_RANGE_UNSHARE flag is specified
1822 	 * until this new Linux API stabilizes.
1823 	 */
1824 
1825 	if ((args->flags & ~(LINUX_CLOSE_RANGE_CLOEXEC)) != 0)
1826 		return (EINVAL);
1827 	if (args->first > args->last)
1828 		return (EINVAL);
1829 	if ((args->flags & LINUX_CLOSE_RANGE_CLOEXEC) != 0)
1830 		flags |= CLOSE_RANGE_CLOEXEC;
1831 	return (kern_close_range(td, flags, args->first, args->last));
1832 }
1833 
1834 int
1835 linux_enobufs2eagain(struct thread *td, int fd, int error)
1836 {
1837 	struct file *fp;
1838 
1839 	if (error != ENOBUFS)
1840 		return (error);
1841 	if (fget(td, fd, &cap_no_rights, &fp) != 0)
1842 		return (error);
1843 	if (fp->f_type == DTYPE_SOCKET && (fp->f_flag & FNONBLOCK) != 0)
1844 		error = EAGAIN;
1845 	fdrop(fp, td);
1846 	return (error);
1847 }
1848 
1849 int
1850 linux_write(struct thread *td, struct linux_write_args *args)
1851 {
1852 	struct write_args bargs = {
1853 		.fd	= args->fd,
1854 		.buf	= args->buf,
1855 		.nbyte	= args->nbyte,
1856 	};
1857 
1858 	return (linux_enobufs2eagain(td, args->fd, sys_write(td, &bargs)));
1859 }
1860 
1861 int
1862 linux_writev(struct thread *td, struct linux_writev_args *args)
1863 {
1864 	struct uio *auio;
1865 	int error;
1866 
1867 #ifdef COMPAT_LINUX32
1868 	error = freebsd32_copyinuio(PTRIN(args->iovp), args->iovcnt, &auio);
1869 #else
1870 	error = copyinuio(args->iovp, args->iovcnt, &auio);
1871 #endif
1872 	if (error != 0)
1873 		return (error);
1874 	error = kern_writev(td, args->fd, auio);
1875 	free(auio, M_IOV);
1876 	return (linux_enobufs2eagain(td, args->fd, error));
1877 }
1878