xref: /freebsd/sys/compat/linux/linux_stats.c (revision a0ee8cc6)
1 /*-
2  * Copyright (c) 1994-1995 Søren Schmidt
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_compat.h"
33 
34 #include <sys/param.h>
35 #include <sys/capsicum.h>
36 #include <sys/dirent.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 #include <sys/proc.h>
40 #include <sys/malloc.h>
41 #include <sys/mount.h>
42 #include <sys/namei.h>
43 #include <sys/stat.h>
44 #include <sys/syscallsubr.h>
45 #include <sys/systm.h>
46 #include <sys/tty.h>
47 #include <sys/vnode.h>
48 #include <sys/conf.h>
49 #include <sys/fcntl.h>
50 
51 #ifdef COMPAT_LINUX32
52 #include <machine/../linux32/linux.h>
53 #include <machine/../linux32/linux32_proto.h>
54 #else
55 #include <machine/../linux/linux.h>
56 #include <machine/../linux/linux_proto.h>
57 #endif
58 
59 #include <compat/linux/linux_util.h>
60 #include <compat/linux/linux_file.h>
61 
62 
63 static void
64 translate_vnhook_major_minor(struct vnode *vp, struct stat *sb)
65 {
66 	int major, minor;
67 
68 	if (vp->v_type == VCHR && vp->v_rdev != NULL &&
69 	    linux_driver_get_major_minor(devtoname(vp->v_rdev),
70 	    &major, &minor) == 0) {
71 		sb->st_rdev = (major << 8 | minor);
72 	}
73 }
74 
75 static int
76 linux_kern_statat(struct thread *td, int flag, int fd, char *path,
77     enum uio_seg pathseg, struct stat *sbp)
78 {
79 
80 	return (kern_statat(td, flag, fd, path, pathseg, sbp,
81 	    translate_vnhook_major_minor));
82 }
83 
84 static int
85 linux_kern_stat(struct thread *td, char *path, enum uio_seg pathseg,
86     struct stat *sbp)
87 {
88 
89 	return (linux_kern_statat(td, 0, AT_FDCWD, path, pathseg, sbp));
90 }
91 
92 static int
93 linux_kern_lstat(struct thread *td, char *path, enum uio_seg pathseg,
94     struct stat *sbp)
95 {
96 
97 	return (linux_kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, path,
98 	    pathseg, sbp));
99 }
100 
101 /*
102  * XXX: This was removed from newstat_copyout(), and almost identical
103  * XXX: code was in stat64_copyout().  findcdev() needs to be replaced
104  * XXX: with something that does lookup and locking properly.
105  * XXX: When somebody fixes this: please try to avoid duplicating it.
106  */
107 #if 0
108 static void
109 disk_foo(struct somestat *tbuf)
110 {
111 	struct cdevsw *cdevsw;
112 	struct cdev *dev;
113 
114 	/* Lie about disk drives which are character devices
115 	 * in FreeBSD but block devices under Linux.
116 	 */
117 	if (S_ISCHR(tbuf.st_mode) &&
118 	    (dev = findcdev(buf->st_rdev)) != NULL) {
119 		cdevsw = dev_refthread(dev);
120 		if (cdevsw != NULL) {
121 			if (cdevsw->d_flags & D_DISK) {
122 				tbuf.st_mode &= ~S_IFMT;
123 				tbuf.st_mode |= S_IFBLK;
124 
125 				/* XXX this may not be quite right */
126 				/* Map major number to 0 */
127 				tbuf.st_dev = minor(buf->st_dev) & 0xf;
128 				tbuf.st_rdev = buf->st_rdev & 0xff;
129 			}
130 			dev_relthread(dev);
131 		}
132 	}
133 
134 }
135 #endif
136 
137 static void
138 translate_fd_major_minor(struct thread *td, int fd, struct stat *buf)
139 {
140 	struct file *fp;
141 	struct vnode *vp;
142 	cap_rights_t rights;
143 	int major, minor;
144 
145 	/*
146 	 * No capability rights required here.
147 	 */
148 	if ((!S_ISCHR(buf->st_mode) && !S_ISBLK(buf->st_mode)) ||
149 	    fget(td, fd, cap_rights_init(&rights), &fp) != 0)
150 		return;
151 	vp = fp->f_vnode;
152 	if (vp != NULL && vp->v_rdev != NULL &&
153 	    linux_driver_get_major_minor(devtoname(vp->v_rdev),
154 					 &major, &minor) == 0) {
155 		buf->st_rdev = (major << 8 | minor);
156 	} else if (fp->f_type == DTYPE_PTS) {
157 		struct tty *tp = fp->f_data;
158 
159 		/* Convert the numbers for the slave device. */
160 		if (linux_driver_get_major_minor(devtoname(tp->t_dev),
161 					 &major, &minor) == 0) {
162 			buf->st_rdev = (major << 8 | minor);
163 		}
164 	}
165 	fdrop(fp, td);
166 }
167 
168 static int
169 newstat_copyout(struct stat *buf, void *ubuf)
170 {
171 	struct l_newstat tbuf;
172 
173 	bzero(&tbuf, sizeof(tbuf));
174 	tbuf.st_dev = minor(buf->st_dev) | (major(buf->st_dev) << 8);
175 	tbuf.st_ino = buf->st_ino;
176 	tbuf.st_mode = buf->st_mode;
177 	tbuf.st_nlink = buf->st_nlink;
178 	tbuf.st_uid = buf->st_uid;
179 	tbuf.st_gid = buf->st_gid;
180 	tbuf.st_rdev = buf->st_rdev;
181 	tbuf.st_size = buf->st_size;
182 	tbuf.st_atim.tv_sec = buf->st_atim.tv_sec;
183 	tbuf.st_atim.tv_nsec = buf->st_atim.tv_nsec;
184 	tbuf.st_mtim.tv_sec = buf->st_mtim.tv_sec;
185 	tbuf.st_mtim.tv_nsec = buf->st_mtim.tv_nsec;
186 	tbuf.st_ctim.tv_sec = buf->st_ctim.tv_sec;
187 	tbuf.st_ctim.tv_nsec = buf->st_ctim.tv_nsec;
188 	tbuf.st_blksize = buf->st_blksize;
189 	tbuf.st_blocks = buf->st_blocks;
190 
191 	return (copyout(&tbuf, ubuf, sizeof(tbuf)));
192 }
193 
194 int
195 linux_newstat(struct thread *td, struct linux_newstat_args *args)
196 {
197 	struct stat buf;
198 	char *path;
199 	int error;
200 
201 	LCONVPATHEXIST(td, args->path, &path);
202 
203 #ifdef DEBUG
204 	if (ldebug(newstat))
205 		printf(ARGS(newstat, "%s, *"), path);
206 #endif
207 
208 	error = linux_kern_stat(td, path, UIO_SYSSPACE, &buf);
209 	LFREEPATH(path);
210 	if (error)
211 		return (error);
212 	return (newstat_copyout(&buf, args->buf));
213 }
214 
215 int
216 linux_newlstat(struct thread *td, struct linux_newlstat_args *args)
217 {
218 	struct stat sb;
219 	char *path;
220 	int error;
221 
222 	LCONVPATHEXIST(td, args->path, &path);
223 
224 #ifdef DEBUG
225 	if (ldebug(newlstat))
226 		printf(ARGS(newlstat, "%s, *"), path);
227 #endif
228 
229 	error = linux_kern_lstat(td, path, UIO_SYSSPACE, &sb);
230 	LFREEPATH(path);
231 	if (error)
232 		return (error);
233 	return (newstat_copyout(&sb, args->buf));
234 }
235 
236 int
237 linux_newfstat(struct thread *td, struct linux_newfstat_args *args)
238 {
239 	struct stat buf;
240 	int error;
241 
242 #ifdef DEBUG
243 	if (ldebug(newfstat))
244 		printf(ARGS(newfstat, "%d, *"), args->fd);
245 #endif
246 
247 	error = kern_fstat(td, args->fd, &buf);
248 	translate_fd_major_minor(td, args->fd, &buf);
249 	if (!error)
250 		error = newstat_copyout(&buf, args->buf);
251 
252 	return (error);
253 }
254 
255 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
256 static int
257 stat_copyout(struct stat *buf, void *ubuf)
258 {
259 	struct l_stat lbuf;
260 
261 	bzero(&lbuf, sizeof(lbuf));
262 	lbuf.st_dev = buf->st_dev;
263 	lbuf.st_ino = buf->st_ino;
264 	lbuf.st_mode = buf->st_mode;
265 	lbuf.st_nlink = buf->st_nlink;
266 	lbuf.st_uid = buf->st_uid;
267 	lbuf.st_gid = buf->st_gid;
268 	lbuf.st_rdev = buf->st_rdev;
269 	if (buf->st_size < (quad_t)1 << 32)
270 		lbuf.st_size = buf->st_size;
271 	else
272 		lbuf.st_size = -2;
273 	lbuf.st_atim.tv_sec = buf->st_atim.tv_sec;
274 	lbuf.st_atim.tv_nsec = buf->st_atim.tv_nsec;
275 	lbuf.st_mtim.tv_sec = buf->st_mtim.tv_sec;
276 	lbuf.st_mtim.tv_nsec = buf->st_mtim.tv_nsec;
277 	lbuf.st_ctim.tv_sec = buf->st_ctim.tv_sec;
278 	lbuf.st_ctim.tv_nsec = buf->st_ctim.tv_nsec;
279 	lbuf.st_blksize = buf->st_blksize;
280 	lbuf.st_blocks = buf->st_blocks;
281 	lbuf.st_flags = buf->st_flags;
282 	lbuf.st_gen = buf->st_gen;
283 
284 	return (copyout(&lbuf, ubuf, sizeof(lbuf)));
285 }
286 
287 int
288 linux_stat(struct thread *td, struct linux_stat_args *args)
289 {
290 	struct stat buf;
291 	char *path;
292 	int error;
293 
294 	LCONVPATHEXIST(td, args->path, &path);
295 
296 #ifdef DEBUG
297 	if (ldebug(stat))
298 		printf(ARGS(stat, "%s, *"), path);
299 #endif
300 	error = linux_kern_stat(td, path, UIO_SYSSPACE, &buf);
301 	if (error) {
302 		LFREEPATH(path);
303 		return (error);
304 	}
305 	LFREEPATH(path);
306 	return(stat_copyout(&buf, args->up));
307 }
308 
309 int
310 linux_lstat(struct thread *td, struct linux_lstat_args *args)
311 {
312 	struct stat buf;
313 	char *path;
314 	int error;
315 
316 	LCONVPATHEXIST(td, args->path, &path);
317 
318 #ifdef DEBUG
319 	if (ldebug(lstat))
320 		printf(ARGS(lstat, "%s, *"), path);
321 #endif
322 	error = linux_kern_lstat(td, path, UIO_SYSSPACE, &buf);
323 	if (error) {
324 		LFREEPATH(path);
325 		return (error);
326 	}
327 	LFREEPATH(path);
328 	return(stat_copyout(&buf, args->up));
329 }
330 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
331 
332 struct l_statfs {
333 	l_long		f_type;
334 	l_long		f_bsize;
335 	l_long		f_blocks;
336 	l_long		f_bfree;
337 	l_long		f_bavail;
338 	l_long		f_files;
339 	l_long		f_ffree;
340 	l_fsid_t	f_fsid;
341 	l_long		f_namelen;
342 	l_long		f_spare[6];
343 };
344 
345 #define	LINUX_CODA_SUPER_MAGIC	0x73757245L
346 #define	LINUX_EXT2_SUPER_MAGIC	0xEF53L
347 #define	LINUX_HPFS_SUPER_MAGIC	0xf995e849L
348 #define	LINUX_ISOFS_SUPER_MAGIC	0x9660L
349 #define	LINUX_MSDOS_SUPER_MAGIC	0x4d44L
350 #define	LINUX_NCP_SUPER_MAGIC	0x564cL
351 #define	LINUX_NFS_SUPER_MAGIC	0x6969L
352 #define	LINUX_NTFS_SUPER_MAGIC	0x5346544EL
353 #define	LINUX_PROC_SUPER_MAGIC	0x9fa0L
354 #define	LINUX_UFS_SUPER_MAGIC	0x00011954L	/* XXX - UFS_MAGIC in Linux */
355 #define LINUX_DEVFS_SUPER_MAGIC	0x1373L
356 #define	LINUX_SHMFS_MAGIC	0x01021994
357 
358 static long
359 bsd_to_linux_ftype(const char *fstypename)
360 {
361 	int i;
362 	static struct {const char *bsd_name; long linux_type;} b2l_tbl[] = {
363 		{"ufs",     LINUX_UFS_SUPER_MAGIC},
364 		{"cd9660",  LINUX_ISOFS_SUPER_MAGIC},
365 		{"nfs",     LINUX_NFS_SUPER_MAGIC},
366 		{"ext2fs",  LINUX_EXT2_SUPER_MAGIC},
367 		{"procfs",  LINUX_PROC_SUPER_MAGIC},
368 		{"msdosfs", LINUX_MSDOS_SUPER_MAGIC},
369 		{"ntfs",    LINUX_NTFS_SUPER_MAGIC},
370 		{"nwfs",    LINUX_NCP_SUPER_MAGIC},
371 		{"hpfs",    LINUX_HPFS_SUPER_MAGIC},
372 		{"coda",    LINUX_CODA_SUPER_MAGIC},
373 		{"devfs",   LINUX_DEVFS_SUPER_MAGIC},
374 		{"tmpfs",   LINUX_SHMFS_MAGIC},
375 		{NULL,      0L}};
376 
377 	for (i = 0; b2l_tbl[i].bsd_name != NULL; i++)
378 		if (strcmp(b2l_tbl[i].bsd_name, fstypename) == 0)
379 			return (b2l_tbl[i].linux_type);
380 
381 	return (0L);
382 }
383 
384 static void
385 bsd_to_linux_statfs(struct statfs *bsd_statfs, struct l_statfs *linux_statfs)
386 {
387 
388 	linux_statfs->f_type = bsd_to_linux_ftype(bsd_statfs->f_fstypename);
389 	linux_statfs->f_bsize = bsd_statfs->f_bsize;
390 	linux_statfs->f_blocks = bsd_statfs->f_blocks;
391 	linux_statfs->f_bfree = bsd_statfs->f_bfree;
392 	linux_statfs->f_bavail = bsd_statfs->f_bavail;
393 	linux_statfs->f_ffree = bsd_statfs->f_ffree;
394 	linux_statfs->f_files = bsd_statfs->f_files;
395 	linux_statfs->f_fsid.val[0] = bsd_statfs->f_fsid.val[0];
396 	linux_statfs->f_fsid.val[1] = bsd_statfs->f_fsid.val[1];
397 	linux_statfs->f_namelen = MAXNAMLEN;
398 }
399 
400 int
401 linux_statfs(struct thread *td, struct linux_statfs_args *args)
402 {
403 	struct l_statfs linux_statfs;
404 	struct statfs bsd_statfs;
405 	char *path;
406 	int error;
407 
408 	LCONVPATHEXIST(td, args->path, &path);
409 
410 #ifdef DEBUG
411 	if (ldebug(statfs))
412 		printf(ARGS(statfs, "%s, *"), path);
413 #endif
414 	error = kern_statfs(td, path, UIO_SYSSPACE, &bsd_statfs);
415 	LFREEPATH(path);
416 	if (error)
417 		return (error);
418 	bsd_to_linux_statfs(&bsd_statfs, &linux_statfs);
419 	return copyout(&linux_statfs, args->buf, sizeof(linux_statfs));
420 }
421 
422 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
423 static void
424 bsd_to_linux_statfs64(struct statfs *bsd_statfs, struct l_statfs64 *linux_statfs)
425 {
426 
427 	linux_statfs->f_type = bsd_to_linux_ftype(bsd_statfs->f_fstypename);
428 	linux_statfs->f_bsize = bsd_statfs->f_bsize;
429 	linux_statfs->f_blocks = bsd_statfs->f_blocks;
430 	linux_statfs->f_bfree = bsd_statfs->f_bfree;
431 	linux_statfs->f_bavail = bsd_statfs->f_bavail;
432 	linux_statfs->f_ffree = bsd_statfs->f_ffree;
433 	linux_statfs->f_files = bsd_statfs->f_files;
434 	linux_statfs->f_fsid.val[0] = bsd_statfs->f_fsid.val[0];
435 	linux_statfs->f_fsid.val[1] = bsd_statfs->f_fsid.val[1];
436 	linux_statfs->f_namelen = MAXNAMLEN;
437 }
438 
439 int
440 linux_statfs64(struct thread *td, struct linux_statfs64_args *args)
441 {
442 	struct l_statfs64 linux_statfs;
443 	struct statfs bsd_statfs;
444 	char *path;
445 	int error;
446 
447 	if (args->bufsize != sizeof(struct l_statfs64))
448 		return EINVAL;
449 
450 	LCONVPATHEXIST(td, args->path, &path);
451 
452 #ifdef DEBUG
453 	if (ldebug(statfs64))
454 		printf(ARGS(statfs64, "%s, *"), path);
455 #endif
456 	error = kern_statfs(td, path, UIO_SYSSPACE, &bsd_statfs);
457 	LFREEPATH(path);
458 	if (error)
459 		return (error);
460 	bsd_to_linux_statfs64(&bsd_statfs, &linux_statfs);
461 	return copyout(&linux_statfs, args->buf, sizeof(linux_statfs));
462 }
463 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
464 
465 int
466 linux_fstatfs(struct thread *td, struct linux_fstatfs_args *args)
467 {
468 	struct l_statfs linux_statfs;
469 	struct statfs bsd_statfs;
470 	int error;
471 
472 #ifdef DEBUG
473 	if (ldebug(fstatfs))
474 		printf(ARGS(fstatfs, "%d, *"), args->fd);
475 #endif
476 	error = kern_fstatfs(td, args->fd, &bsd_statfs);
477 	if (error)
478 		return error;
479 	bsd_to_linux_statfs(&bsd_statfs, &linux_statfs);
480 	return copyout(&linux_statfs, args->buf, sizeof(linux_statfs));
481 }
482 
483 struct l_ustat
484 {
485 	l_daddr_t	f_tfree;
486 	l_ino_t		f_tinode;
487 	char		f_fname[6];
488 	char		f_fpack[6];
489 };
490 
491 int
492 linux_ustat(struct thread *td, struct linux_ustat_args *args)
493 {
494 #ifdef DEBUG
495 	if (ldebug(ustat))
496 		printf(ARGS(ustat, "%ju, *"), (uintmax_t)args->dev);
497 #endif
498 
499 	return (EOPNOTSUPP);
500 }
501 
502 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
503 
504 static int
505 stat64_copyout(struct stat *buf, void *ubuf)
506 {
507 	struct l_stat64 lbuf;
508 
509 	bzero(&lbuf, sizeof(lbuf));
510 	lbuf.st_dev = minor(buf->st_dev) | (major(buf->st_dev) << 8);
511 	lbuf.st_ino = buf->st_ino;
512 	lbuf.st_mode = buf->st_mode;
513 	lbuf.st_nlink = buf->st_nlink;
514 	lbuf.st_uid = buf->st_uid;
515 	lbuf.st_gid = buf->st_gid;
516 	lbuf.st_rdev = buf->st_rdev;
517 	lbuf.st_size = buf->st_size;
518 	lbuf.st_atim.tv_sec = buf->st_atim.tv_sec;
519 	lbuf.st_atim.tv_nsec = buf->st_atim.tv_nsec;
520 	lbuf.st_mtim.tv_sec = buf->st_mtim.tv_sec;
521 	lbuf.st_mtim.tv_nsec = buf->st_mtim.tv_nsec;
522 	lbuf.st_ctim.tv_sec = buf->st_ctim.tv_sec;
523 	lbuf.st_ctim.tv_nsec = buf->st_ctim.tv_nsec;
524 	lbuf.st_blksize = buf->st_blksize;
525 	lbuf.st_blocks = buf->st_blocks;
526 
527 	/*
528 	 * The __st_ino field makes all the difference. In the Linux kernel
529 	 * it is conditionally compiled based on STAT64_HAS_BROKEN_ST_INO,
530 	 * but without the assignment to __st_ino the runtime linker refuses
531 	 * to mmap(2) any shared libraries. I guess it's broken alright :-)
532 	 */
533 	lbuf.__st_ino = buf->st_ino;
534 
535 	return (copyout(&lbuf, ubuf, sizeof(lbuf)));
536 }
537 
538 int
539 linux_stat64(struct thread *td, struct linux_stat64_args *args)
540 {
541 	struct stat buf;
542 	char *filename;
543 	int error;
544 
545 	LCONVPATHEXIST(td, args->filename, &filename);
546 
547 #ifdef DEBUG
548 	if (ldebug(stat64))
549 		printf(ARGS(stat64, "%s, *"), filename);
550 #endif
551 
552 	error = linux_kern_stat(td, filename, UIO_SYSSPACE, &buf);
553 	LFREEPATH(filename);
554 	if (error)
555 		return (error);
556 	return (stat64_copyout(&buf, args->statbuf));
557 }
558 
559 int
560 linux_lstat64(struct thread *td, struct linux_lstat64_args *args)
561 {
562 	struct stat sb;
563 	char *filename;
564 	int error;
565 
566 	LCONVPATHEXIST(td, args->filename, &filename);
567 
568 #ifdef DEBUG
569 	if (ldebug(lstat64))
570 		printf(ARGS(lstat64, "%s, *"), args->filename);
571 #endif
572 
573 	error = linux_kern_lstat(td, filename, UIO_SYSSPACE, &sb);
574 	LFREEPATH(filename);
575 	if (error)
576 		return (error);
577 	return (stat64_copyout(&sb, args->statbuf));
578 }
579 
580 int
581 linux_fstat64(struct thread *td, struct linux_fstat64_args *args)
582 {
583 	struct stat buf;
584 	int error;
585 
586 #ifdef DEBUG
587 	if (ldebug(fstat64))
588 		printf(ARGS(fstat64, "%d, *"), args->fd);
589 #endif
590 
591 	error = kern_fstat(td, args->fd, &buf);
592 	translate_fd_major_minor(td, args->fd, &buf);
593 	if (!error)
594 		error = stat64_copyout(&buf, args->statbuf);
595 
596 	return (error);
597 }
598 
599 int
600 linux_fstatat64(struct thread *td, struct linux_fstatat64_args *args)
601 {
602 	char *path;
603 	int error, dfd, flag;
604 	struct stat buf;
605 
606 	if (args->flag & ~LINUX_AT_SYMLINK_NOFOLLOW)
607 		return (EINVAL);
608 	flag = (args->flag & LINUX_AT_SYMLINK_NOFOLLOW) ?
609 	    AT_SYMLINK_NOFOLLOW : 0;
610 
611 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
612 	LCONVPATHEXIST_AT(td, args->pathname, &path, dfd);
613 
614 #ifdef DEBUG
615 	if (ldebug(fstatat64))
616 		printf(ARGS(fstatat64, "%i, %s, %i"), args->dfd, path, args->flag);
617 #endif
618 
619 	error = linux_kern_statat(td, flag, dfd, path, UIO_SYSSPACE, &buf);
620 	if (!error)
621 		error = stat64_copyout(&buf, args->statbuf);
622 	LFREEPATH(path);
623 
624 	return (error);
625 }
626 
627 #else /* __amd64__ && !COMPAT_LINUX32 */
628 
629 int
630 linux_newfstatat(struct thread *td, struct linux_newfstatat_args *args)
631 {
632 	char *path;
633 	int error, dfd, flag;
634 	struct stat buf;
635 
636 	if (args->flag & ~LINUX_AT_SYMLINK_NOFOLLOW)
637 		return (EINVAL);
638 	flag = (args->flag & LINUX_AT_SYMLINK_NOFOLLOW) ?
639 	    AT_SYMLINK_NOFOLLOW : 0;
640 
641 	dfd = (args->dfd == LINUX_AT_FDCWD) ? AT_FDCWD : args->dfd;
642 	LCONVPATHEXIST_AT(td, args->pathname, &path, dfd);
643 
644 #ifdef DEBUG
645 	if (ldebug(newfstatat))
646 		printf(ARGS(newfstatat, "%i, %s, %i"), args->dfd, path, args->flag);
647 #endif
648 
649 	error = linux_kern_statat(td, flag, dfd, path, UIO_SYSSPACE, &buf);
650 	if (error == 0)
651 		error = newstat_copyout(&buf, args->statbuf);
652 	LFREEPATH(path);
653 
654 	return (error);
655 }
656 
657 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
658 
659 int
660 linux_syncfs(struct thread *td, struct linux_syncfs_args *args)
661 {
662 	cap_rights_t rights;
663 	struct mount *mp;
664 	struct vnode *vp;
665 	int error, save;
666 
667 	error = fgetvp(td, args->fd, cap_rights_init(&rights, CAP_FSYNC), &vp);
668 	if (error != 0)
669 		/*
670 		 * Linux syncfs() returns only EBADF, however fgetvp()
671 		 * can return EINVAL in case of file descriptor does
672 		 * not represent a vnode. XXX.
673 		 */
674 		return (error);
675 
676 	mp = vp->v_mount;
677 	mtx_lock(&mountlist_mtx);
678 	error = vfs_busy(mp, MBF_MNTLSTLOCK);
679 	if (error != 0) {
680 		/* See comment above. */
681 		mtx_unlock(&mountlist_mtx);
682 		goto out;
683 	}
684 	if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
685 	    vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
686 		save = curthread_pflags_set(TDP_SYNCIO);
687 		vfs_msync(mp, MNT_NOWAIT);
688 		VFS_SYNC(mp, MNT_NOWAIT);
689 		curthread_pflags_restore(save);
690 		vn_finished_write(mp);
691 	}
692 	vfs_unbusy(mp);
693 
694  out:
695 	vrele(vp);
696 	return (error);
697 }
698