xref: /freebsd/sys/sys/file.h (revision 4c3a868d13c053ef173268cdfe1365978a282178)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef _SYS_FILE_H_
33 #define	_SYS_FILE_H_
34 
35 #ifndef _KERNEL
36 #include <sys/types.h> /* XXX */
37 #include <sys/fcntl.h>
38 #include <sys/unistd.h>
39 #else
40 #include <sys/errno.h>
41 #include <sys/_lock.h>
42 #include <sys/_mutex.h>
43 #include <sys/_null.h>
44 #include <sys/queue.h>
45 #include <sys/refcount.h>
46 #include <vm/vm.h>
47 
48 struct filedesc;
49 struct proc;
50 struct stat;
51 struct thread;
52 struct uio;
53 struct knote;
54 struct vnode;
55 struct nameidata;
56 
57 #endif /* _KERNEL */
58 
59 #define	DTYPE_NONE	0	/* not yet initialized */
60 #define	DTYPE_VNODE	1	/* file */
61 #define	DTYPE_SOCKET	2	/* communications endpoint */
62 #define	DTYPE_PIPE	3	/* pipe */
63 #define	DTYPE_FIFO	4	/* fifo (named pipe) */
64 #define	DTYPE_KQUEUE	5	/* event queue */
65 #define	DTYPE_CRYPTO	6	/* crypto */
66 #define	DTYPE_MQUEUE	7	/* posix message queue */
67 #define	DTYPE_SHM	8	/* swap-backed shared memory */
68 #define	DTYPE_SEM	9	/* posix semaphore */
69 #define	DTYPE_PTS	10	/* pseudo teletype master device */
70 #define	DTYPE_DEV	11	/* Device specific fd type */
71 #define	DTYPE_PROCDESC	12	/* process descriptor */
72 #define	DTYPE_EVENTFD	13	/* eventfd */
73 #define	DTYPE_TIMERFD	14	/* timerfd */
74 #define	DTYPE_INOTIFY	15	/* inotify descriptor */
75 #define	DTYPE_JAILDESC	16	/* jail descriptor */
76 
77 #ifdef _KERNEL
78 
79 struct file;
80 struct filecaps;
81 struct kaiocb;
82 struct kinfo_file;
83 struct ucred;
84 
85 #define	FOF_OFFSET	0x01	/* Use the offset in uio argument */
86 #define	FOF_NOLOCK	0x02	/* Do not take FOFFSET_LOCK */
87 #define	FOF_NEXTOFF_R	0x04	/* Also update f_nextoff[UIO_READ] */
88 #define	FOF_NEXTOFF_W	0x08	/* Also update f_nextoff[UIO_WRITE] */
89 #define	FOF_NOUPDATE	0x10	/* Do not update f_offset */
90 off_t foffset_lock(struct file *fp, int flags);
91 void foffset_lock_pair(struct file *fp1, off_t *off1p, struct file *fp2,
92     off_t *off2p, int flags);
93 void foffset_lock_uio(struct file *fp, struct uio *uio, int flags);
94 void foffset_unlock(struct file *fp, off_t val, int flags);
95 void foffset_unlock_uio(struct file *fp, struct uio *uio, int flags);
96 void fsetfl_lock(struct file *fp);
97 void fsetfl_unlock(struct file *fp);
98 
99 static inline off_t
foffset_get(struct file * fp)100 foffset_get(struct file *fp)
101 {
102 
103 	return (foffset_lock(fp, FOF_NOLOCK));
104 }
105 
106 typedef int fo_rdwr_t(struct file *fp, struct uio *uio,
107 		    struct ucred *active_cred, int flags,
108 		    struct thread *td);
109 typedef	int fo_truncate_t(struct file *fp, off_t length,
110 		    struct ucred *active_cred, struct thread *td);
111 typedef	int fo_ioctl_t(struct file *fp, u_long com, void *data,
112 		    struct ucred *active_cred, struct thread *td);
113 typedef	int fo_poll_t(struct file *fp, int events,
114 		    struct ucred *active_cred, struct thread *td);
115 typedef	int fo_kqfilter_t(struct file *fp, struct knote *kn);
116 typedef	int fo_stat_t(struct file *fp, struct stat *sb,
117 		    struct ucred *active_cred);
118 typedef	int fo_close_t(struct file *fp, struct thread *td);
119 typedef	int fo_chmod_t(struct file *fp, mode_t mode,
120 		    struct ucred *active_cred, struct thread *td);
121 typedef	int fo_chown_t(struct file *fp, uid_t uid, gid_t gid,
122 		    struct ucred *active_cred, struct thread *td);
123 typedef int fo_sendfile_t(struct file *fp, int sockfd, struct uio *hdr_uio,
124 		    struct uio *trl_uio, off_t offset, size_t nbytes,
125 		    off_t *sent, int flags, struct thread *td);
126 typedef int fo_seek_t(struct file *fp, off_t offset, int whence,
127 		    struct thread *td);
128 typedef int fo_fill_kinfo_t(struct file *fp, struct kinfo_file *kif,
129 		    struct filedesc *fdp);
130 typedef int fo_mmap_t(struct file *fp, vm_map_t map, vm_offset_t *addr,
131 		    vm_size_t size, vm_prot_t prot, vm_prot_t cap_maxprot,
132 		    int flags, vm_ooffset_t foff, struct thread *td);
133 typedef int fo_aio_queue_t(struct file *fp, struct kaiocb *job);
134 typedef int fo_add_seals_t(struct file *fp, int flags);
135 typedef int fo_get_seals_t(struct file *fp, int *flags);
136 typedef int fo_fallocate_t(struct file *fp, off_t offset, off_t len,
137 		    struct thread *td);
138 typedef int fo_fspacectl_t(struct file *fp, int cmd,
139 		    off_t *offset, off_t *length, int flags,
140 		    struct ucred *active_cred, struct thread *td);
141 typedef int fo_cmp_t(struct file *fp, struct file *fp1, struct thread *td);
142 typedef int fo_spare_t(struct file *fp);
143 typedef	int fo_flags_t;
144 
145 struct fileops {
146 	fo_rdwr_t	*fo_read;
147 	fo_rdwr_t	*fo_write;
148 	fo_truncate_t	*fo_truncate;
149 	fo_ioctl_t	*fo_ioctl;
150 	fo_poll_t	*fo_poll;
151 	fo_kqfilter_t	*fo_kqfilter;
152 	fo_stat_t	*fo_stat;
153 	fo_close_t	*fo_close;
154 	fo_chmod_t	*fo_chmod;
155 	fo_chown_t	*fo_chown;
156 	fo_sendfile_t	*fo_sendfile;
157 	fo_seek_t	*fo_seek;
158 	fo_fill_kinfo_t	*fo_fill_kinfo;
159 	fo_mmap_t	*fo_mmap;
160 	fo_aio_queue_t	*fo_aio_queue;
161 	fo_add_seals_t	*fo_add_seals;
162 	fo_get_seals_t	*fo_get_seals;
163 	fo_fallocate_t	*fo_fallocate;
164 	fo_fspacectl_t	*fo_fspacectl;
165 	fo_cmp_t	*fo_cmp;
166 	fo_spare_t	*fo_spares[8];	/* Spare slots */
167 	fo_flags_t	fo_flags;	/* DFLAG_* below */
168 };
169 
170 #define DFLAG_PASSABLE	0x01	/* may be passed via unix sockets. */
171 #define DFLAG_SEEKABLE	0x02	/* seekable / nonsequential */
172 #endif /* _KERNEL */
173 
174 #if defined(_KERNEL) || defined(_WANT_FILE)
175 /*
176  * Kernel descriptor table.
177  * One entry for each open kernel vnode and socket.
178  *
179  * Below is the list of locks that protects members in struct file.
180  *
181  * (a) f_vnode lock required (shared allows both reads and writes)
182  * (f) updated with atomics and blocking on sleepq
183  * (d) cdevpriv_mtx
184  * none	not locked
185  */
186 
187 #if __BSD_VISIBLE
188 struct fadvise_info {
189 	int		fa_advice;	/* (f) FADV_* type. */
190 	off_t		fa_start;	/* (f) Region start. */
191 	off_t		fa_end;		/* (f) Region end. */
192 };
193 
194 struct file {
195 	volatile u_int	f_flag;		/* see fcntl.h */
196 	volatile u_int 	f_count;	/* reference count */
197 	void		*f_data;	/* file descriptor specific data */
198 	const struct fileops *f_ops;	/* File operations */
199 	struct vnode 	*f_vnode;	/* NULL or applicable vnode */
200 	struct ucred	*f_cred;	/* associated credentials. */
201 	short		f_type;		/* descriptor type */
202 	short		f_vflags;	/* (f) Sleep lock flags for members */
203 	/*
204 	 *  DTYPE_VNODE specific fields.
205 	 */
206 	union {
207 		int16_t	f_seqcount[2];	/* (a) Count of seq. reads and writes. */
208 		int	f_pipegen;
209 	};
210 	off_t		f_nextoff[2];	/* next expected read/write offset. */
211 	union {
212 		struct cdev_privdata *fvn_cdevpriv;
213 					/* (d) Private data for the cdev. */
214 		struct fadvise_info *fvn_advice;
215 	} f_vnun;
216 	/*
217 	 *  DFLAG_SEEKABLE specific fields
218 	 */
219 	off_t		f_offset;
220 };
221 
222 #define	f_cdevpriv	f_vnun.fvn_cdevpriv
223 #define	f_advice	f_vnun.fvn_advice
224 
225 #define	FILE_V_FOFFSET_LOCKED		0x0001
226 #define	FILE_V_FOFFSET_LOCK_WAITING	0x0002
227 #define	FILE_V_SETFL_LOCKED		0x0004
228 #define	FILE_V_SETFL_LOCK_WAITING	0x0008
229 #endif /* __BSD_VISIBLE */
230 
231 #endif /* _KERNEL || _WANT_FILE */
232 
233 /*
234  * Userland version of struct file, for sysctl
235  */
236 #if __BSD_VISIBLE
237 struct xfile {
238 	ksize_t	xf_size;	/* size of struct xfile */
239 	pid_t	xf_pid;		/* owning process */
240 	uid_t	xf_uid;		/* effective uid of owning process */
241 	int	xf_fd;		/* descriptor number */
242 	int	_xf_int_pad1;
243 	kvaddr_t xf_file;	/* address of struct file */
244 	short	xf_type;	/* descriptor type */
245 	short	_xf_short_pad1;
246 	int	xf_count;	/* reference count */
247 	int	xf_msgcount;	/* references from message queue */
248 	int	_xf_int_pad2;
249 	off_t	xf_offset;	/* file offset */
250 	kvaddr_t xf_data;	/* file descriptor specific data */
251 	kvaddr_t xf_vnode;	/* vnode pointer */
252 	u_int	xf_flag;	/* flags (see fcntl.h) */
253 	int	_xf_int_pad3;
254 	int64_t	_xf_int64_pad[6];
255 };
256 #endif /* __BSD_VISIBLE */
257 
258 #ifdef _KERNEL
259 
260 extern const struct fileops vnops;
261 extern const struct fileops badfileops;
262 extern const struct fileops path_fileops;
263 extern const struct fileops socketops;
264 extern int maxfiles;		/* kernel limit on number of open files */
265 extern int maxfilesperproc;	/* per process limit on number of open files */
266 
267 int fget(struct thread *td, int fd, const cap_rights_t *rightsp,
268     struct file **fpp);
269 int fget_mmap(struct thread *td, int fd, const cap_rights_t *rightsp,
270     vm_prot_t *maxprotp, struct file **fpp);
271 int fget_read(struct thread *td, int fd, const cap_rights_t *rightsp,
272     struct file **fpp);
273 int fget_write(struct thread *td, int fd, const cap_rights_t *rightsp,
274     struct file **fpp);
275 int fget_fcntl(struct thread *td, int fd, const cap_rights_t *rightsp,
276     int needfcntl, struct file **fpp);
277 int _fdrop(struct file *fp, struct thread *td);
278 int fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp);
279 int fget_remote_foreach(struct thread *td, struct proc *p,
280     int (*fn)(struct proc *, int, struct file *, void *), void *arg);
281 
282 fo_rdwr_t	invfo_rdwr;
283 fo_truncate_t	invfo_truncate;
284 fo_ioctl_t	invfo_ioctl;
285 fo_poll_t	invfo_poll;
286 fo_kqfilter_t	invfo_kqfilter;
287 fo_chmod_t	invfo_chmod;
288 fo_chown_t	invfo_chown;
289 fo_sendfile_t	invfo_sendfile;
290 fo_stat_t	vn_statfile;
291 fo_sendfile_t	vn_sendfile;
292 fo_seek_t	vn_seek;
293 fo_fill_kinfo_t	vn_fill_kinfo;
294 fo_kqfilter_t	vn_kqfilter_opath;
295 int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif);
296 int file_kcmp_generic(struct file *fp1, struct file *fp2, struct thread *td);
297 
298 void finit(struct file *, u_int, short, void *, const struct fileops *);
299 void finit_vnode(struct file *, u_int, void *, const struct fileops *);
300 int fgetvp(struct thread *td, int fd, const cap_rights_t *rightsp,
301     struct vnode **vpp);
302 int fgetvp_exec(struct thread *td, int fd, const cap_rights_t *rightsp,
303     struct vnode **vpp);
304 int fgetvp_rights(struct thread *td, int fd, const cap_rights_t *needrightsp,
305     struct filecaps *havecaps, struct vnode **vpp);
306 int fgetvp_read(struct thread *td, int fd, const cap_rights_t *rightsp,
307     struct vnode **vpp);
308 int fgetvp_write(struct thread *td, int fd, const cap_rights_t *rightsp,
309     struct vnode **vpp);
310 int fgetvp_lookup_smr(struct nameidata *ndp, struct vnode **vpp, int *flagsp);
311 int fgetvp_lookup(struct nameidata *ndp, struct vnode **vpp);
312 
313 static __inline __result_use_check bool
fhold(struct file * fp)314 fhold(struct file *fp)
315 {
316 	return (refcount_acquire_checked(&fp->f_count));
317 }
318 
319 #define	fdrop(fp, td)		({				\
320 	struct file *_fp;					\
321 	int _error;						\
322 								\
323 	_error = 0;						\
324 	_fp = (fp);						\
325 	if (__predict_false(refcount_release(&_fp->f_count)))	\
326 		_error = _fdrop(_fp, td);			\
327 	_error;							\
328 })
329 
330 #define	fdrop_close(fp, td)		({			\
331 	struct file *_fp;					\
332 	int _error;						\
333 								\
334 	_error = 0;						\
335 	_fp = (fp);						\
336 	if (__predict_true(refcount_release(&_fp->f_count)))	\
337 		_error = _fdrop(_fp, td);			\
338 	_error;							\
339 })
340 
341 static __inline fo_rdwr_t	fo_read;
342 static __inline fo_rdwr_t	fo_write;
343 static __inline fo_truncate_t	fo_truncate;
344 static __inline fo_ioctl_t	fo_ioctl;
345 static __inline fo_poll_t	fo_poll;
346 static __inline fo_kqfilter_t	fo_kqfilter;
347 static __inline fo_stat_t	fo_stat;
348 static __inline fo_close_t	fo_close;
349 static __inline fo_chmod_t	fo_chmod;
350 static __inline fo_chown_t	fo_chown;
351 static __inline fo_sendfile_t	fo_sendfile;
352 
353 static __inline int
fo_read(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)354 fo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
355     int flags, struct thread *td)
356 {
357 
358 	return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
359 }
360 
361 static __inline int
fo_write(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)362 fo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
363     int flags, struct thread *td)
364 {
365 
366 	return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
367 }
368 
369 static __inline int
fo_truncate(struct file * fp,off_t length,struct ucred * active_cred,struct thread * td)370 fo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
371     struct thread *td)
372 {
373 
374 	return ((*fp->f_ops->fo_truncate)(fp, length, active_cred, td));
375 }
376 
377 static __inline int
fo_ioctl(struct file * fp,u_long com,void * data,struct ucred * active_cred,struct thread * td)378 fo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
379     struct thread *td)
380 {
381 
382 	return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
383 }
384 
385 static __inline int
fo_poll(struct file * fp,int events,struct ucred * active_cred,struct thread * td)386 fo_poll(struct file *fp, int events, struct ucred *active_cred,
387     struct thread *td)
388 {
389 
390 	return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
391 }
392 
393 static __inline int
fo_stat(struct file * fp,struct stat * sb,struct ucred * active_cred)394 fo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred)
395 {
396 
397 	return ((*fp->f_ops->fo_stat)(fp, sb, active_cred));
398 }
399 
400 static __inline int
fo_close(struct file * fp,struct thread * td)401 fo_close(struct file *fp, struct thread *td)
402 {
403 
404 	return ((*fp->f_ops->fo_close)(fp, td));
405 }
406 
407 static __inline int
fo_kqfilter(struct file * fp,struct knote * kn)408 fo_kqfilter(struct file *fp, struct knote *kn)
409 {
410 
411 	return ((*fp->f_ops->fo_kqfilter)(fp, kn));
412 }
413 
414 static __inline int
fo_chmod(struct file * fp,mode_t mode,struct ucred * active_cred,struct thread * td)415 fo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
416     struct thread *td)
417 {
418 
419 	return ((*fp->f_ops->fo_chmod)(fp, mode, active_cred, td));
420 }
421 
422 static __inline int
fo_chown(struct file * fp,uid_t uid,gid_t gid,struct ucred * active_cred,struct thread * td)423 fo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
424     struct thread *td)
425 {
426 
427 	return ((*fp->f_ops->fo_chown)(fp, uid, gid, active_cred, td));
428 }
429 
430 static __inline int
fo_sendfile(struct file * fp,int sockfd,struct uio * hdr_uio,struct uio * trl_uio,off_t offset,size_t nbytes,off_t * sent,int flags,struct thread * td)431 fo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
432     struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
433     struct thread *td)
434 {
435 
436 	return ((*fp->f_ops->fo_sendfile)(fp, sockfd, hdr_uio, trl_uio, offset,
437 	    nbytes, sent, flags, td));
438 }
439 
440 static __inline int
fo_seek(struct file * fp,off_t offset,int whence,struct thread * td)441 fo_seek(struct file *fp, off_t offset, int whence, struct thread *td)
442 {
443 
444 	return ((*fp->f_ops->fo_seek)(fp, offset, whence, td));
445 }
446 
447 static __inline int
fo_fill_kinfo(struct file * fp,struct kinfo_file * kif,struct filedesc * fdp)448 fo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
449 {
450 
451 	return ((*fp->f_ops->fo_fill_kinfo)(fp, kif, fdp));
452 }
453 
454 static __inline int
fo_mmap(struct file * fp,vm_map_t map,vm_offset_t * addr,vm_size_t size,vm_prot_t prot,vm_prot_t cap_maxprot,int flags,vm_ooffset_t foff,struct thread * td)455 fo_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
456     vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
457     struct thread *td)
458 {
459 
460 	if (fp->f_ops->fo_mmap == NULL)
461 		return (ENODEV);
462 	return ((*fp->f_ops->fo_mmap)(fp, map, addr, size, prot, cap_maxprot,
463 	    flags, foff, td));
464 }
465 
466 static __inline int
fo_aio_queue(struct file * fp,struct kaiocb * job)467 fo_aio_queue(struct file *fp, struct kaiocb *job)
468 {
469 
470 	return ((*fp->f_ops->fo_aio_queue)(fp, job));
471 }
472 
473 static __inline int
fo_add_seals(struct file * fp,int seals)474 fo_add_seals(struct file *fp, int seals)
475 {
476 
477 	if (fp->f_ops->fo_add_seals == NULL)
478 		return (EINVAL);
479 	return ((*fp->f_ops->fo_add_seals)(fp, seals));
480 }
481 
482 static __inline int
fo_get_seals(struct file * fp,int * seals)483 fo_get_seals(struct file *fp, int *seals)
484 {
485 
486 	if (fp->f_ops->fo_get_seals == NULL)
487 		return (EINVAL);
488 	return ((*fp->f_ops->fo_get_seals)(fp, seals));
489 }
490 
491 static __inline int
fo_fallocate(struct file * fp,off_t offset,off_t len,struct thread * td)492 fo_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
493 {
494 
495 	if (fp->f_ops->fo_fallocate == NULL)
496 		return (ENODEV);
497 	return ((*fp->f_ops->fo_fallocate)(fp, offset, len, td));
498 }
499 
500 static __inline int
fo_fspacectl(struct file * fp,int cmd,off_t * offset,off_t * length,int flags,struct ucred * active_cred,struct thread * td)501 fo_fspacectl(struct file *fp, int cmd, off_t *offset, off_t *length,
502     int flags, struct ucred *active_cred, struct thread *td)
503 {
504 
505 	if (fp->f_ops->fo_fspacectl == NULL)
506 		return (ENODEV);
507 	return ((*fp->f_ops->fo_fspacectl)(fp, cmd, offset, length, flags,
508 	    active_cred, td));
509 }
510 
511 static __inline int
fo_cmp(struct file * fp1,struct file * fp2,struct thread * td)512 fo_cmp(struct file *fp1, struct file *fp2, struct thread *td)
513 {
514 
515 	if (fp1->f_ops->fo_cmp == NULL)
516 		return (ENODEV);
517 	return ((*fp1->f_ops->fo_cmp)(fp1, fp2, td));
518 }
519 
520 #endif /* _KERNEL */
521 
522 #endif /* !SYS_FILE_H */
523