xref: /f-stack/freebsd/sys/file.h (revision ebf5cedb)
1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  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  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)file.h	8.3 (Berkeley) 1/9/95
30  * $FreeBSD$
31  */
32 
33 #ifndef _SYS_FILE_H_
34 #define	_SYS_FILE_H_
35 
36 #ifndef _KERNEL
37 #include <sys/types.h> /* XXX */
38 #include <sys/fcntl.h>
39 #include <sys/unistd.h>
40 #else
41 #include <sys/queue.h>
42 #include <sys/refcount.h>
43 #include <sys/_lock.h>
44 #include <sys/_mutex.h>
45 #include <vm/vm.h>
46 
47 struct filedesc;
48 struct stat;
49 struct thread;
50 struct uio;
51 struct knote;
52 struct vnode;
53 struct socket;
54 
55 
56 #endif /* _KERNEL */
57 
58 #define	DTYPE_VNODE	1	/* file */
59 #define	DTYPE_SOCKET	2	/* communications endpoint */
60 #define	DTYPE_PIPE	3	/* pipe */
61 #define	DTYPE_FIFO	4	/* fifo (named pipe) */
62 #define	DTYPE_KQUEUE	5	/* event queue */
63 #define	DTYPE_CRYPTO	6	/* crypto */
64 #define	DTYPE_MQUEUE	7	/* posix message queue */
65 #define	DTYPE_SHM	8	/* swap-backed shared memory */
66 #define	DTYPE_SEM	9	/* posix semaphore */
67 #define	DTYPE_PTS	10	/* pseudo teletype master device */
68 #define	DTYPE_DEV	11	/* Device specific fd type */
69 #define	DTYPE_PROCDESC	12	/* process descriptor */
70 #define	DTYPE_LINUXEFD	13	/* emulation eventfd type */
71 
72 #ifdef _KERNEL
73 
74 struct file;
75 struct filecaps;
76 struct kaiocb;
77 struct kinfo_file;
78 struct ucred;
79 
80 #define	FOF_OFFSET	0x01	/* Use the offset in uio argument */
81 #define	FOF_NOLOCK	0x02	/* Do not take FOFFSET_LOCK */
82 #define	FOF_NEXTOFF	0x04	/* Also update f_nextoff */
83 #define	FOF_NOUPDATE	0x10	/* Do not update f_offset */
84 off_t foffset_lock(struct file *fp, int flags);
85 void foffset_lock_uio(struct file *fp, struct uio *uio, int flags);
86 void foffset_unlock(struct file *fp, off_t val, int flags);
87 void foffset_unlock_uio(struct file *fp, struct uio *uio, int flags);
88 
89 static inline off_t
90 foffset_get(struct file *fp)
91 {
92 
93 	return (foffset_lock(fp, FOF_NOLOCK));
94 }
95 
96 typedef int fo_rdwr_t(struct file *fp, struct uio *uio,
97 		    struct ucred *active_cred, int flags,
98 		    struct thread *td);
99 typedef	int fo_truncate_t(struct file *fp, off_t length,
100 		    struct ucred *active_cred, struct thread *td);
101 typedef	int fo_ioctl_t(struct file *fp, u_long com, void *data,
102 		    struct ucred *active_cred, struct thread *td);
103 typedef	int fo_poll_t(struct file *fp, int events,
104 		    struct ucred *active_cred, struct thread *td);
105 typedef	int fo_kqfilter_t(struct file *fp, struct knote *kn);
106 typedef	int fo_stat_t(struct file *fp, struct stat *sb,
107 		    struct ucred *active_cred, struct thread *td);
108 typedef	int fo_close_t(struct file *fp, struct thread *td);
109 typedef	int fo_chmod_t(struct file *fp, mode_t mode,
110 		    struct ucred *active_cred, struct thread *td);
111 typedef	int fo_chown_t(struct file *fp, uid_t uid, gid_t gid,
112 		    struct ucred *active_cred, struct thread *td);
113 typedef int fo_sendfile_t(struct file *fp, int sockfd, struct uio *hdr_uio,
114 		    struct uio *trl_uio, off_t offset, size_t nbytes,
115 		    off_t *sent, int flags, struct thread *td);
116 typedef int fo_seek_t(struct file *fp, off_t offset, int whence,
117 		    struct thread *td);
118 typedef int fo_fill_kinfo_t(struct file *fp, struct kinfo_file *kif,
119 		    struct filedesc *fdp);
120 typedef int fo_mmap_t(struct file *fp, vm_map_t map, vm_offset_t *addr,
121 		    vm_size_t size, vm_prot_t prot, vm_prot_t cap_maxprot,
122 		    int flags, vm_ooffset_t foff, struct thread *td);
123 typedef int fo_aio_queue_t(struct file *fp, struct kaiocb *job);
124 typedef	int fo_flags_t;
125 
126 struct fileops {
127 	fo_rdwr_t	*fo_read;
128 	fo_rdwr_t	*fo_write;
129 	fo_truncate_t	*fo_truncate;
130 	fo_ioctl_t	*fo_ioctl;
131 	fo_poll_t	*fo_poll;
132 	fo_kqfilter_t	*fo_kqfilter;
133 	fo_stat_t	*fo_stat;
134 	fo_close_t	*fo_close;
135 	fo_chmod_t	*fo_chmod;
136 	fo_chown_t	*fo_chown;
137 	fo_sendfile_t	*fo_sendfile;
138 	fo_seek_t	*fo_seek;
139 	fo_fill_kinfo_t	*fo_fill_kinfo;
140 	fo_mmap_t	*fo_mmap;
141 	fo_aio_queue_t	*fo_aio_queue;
142 	fo_flags_t	fo_flags;	/* DFLAG_* below */
143 };
144 
145 #define DFLAG_PASSABLE	0x01	/* may be passed via unix sockets. */
146 #define DFLAG_SEEKABLE	0x02	/* seekable / nonsequential */
147 #endif /* _KERNEL */
148 
149 #if defined(_KERNEL) || defined(_WANT_FILE)
150 /*
151  * Kernel descriptor table.
152  * One entry for each open kernel vnode and socket.
153  *
154  * Below is the list of locks that protects members in struct file.
155  *
156  * (a) f_vnode lock required (shared allows both reads and writes)
157  * (f) protected with mtx_lock(mtx_pool_find(fp))
158  * (d) cdevpriv_mtx
159  * none	not locked
160  */
161 
162 struct fadvise_info {
163 	int		fa_advice;	/* (f) FADV_* type. */
164 	off_t		fa_start;	/* (f) Region start. */
165 	off_t		fa_end;		/* (f) Region end. */
166 };
167 
168 struct file {
169 	void		*f_data;	/* file descriptor specific data */
170 	struct fileops	*f_ops;		/* File operations */
171 	struct ucred	*f_cred;	/* associated credentials. */
172 	struct vnode 	*f_vnode;	/* NULL or applicable vnode */
173 	short		f_type;		/* descriptor type */
174 	short		f_vnread_flags; /* (f) Sleep lock for f_offset */
175 	volatile u_int	f_flag;		/* see fcntl.h */
176 	volatile u_int 	f_count;	/* reference count */
177 	/*
178 	 *  DTYPE_VNODE specific fields.
179 	 */
180 	int		f_seqcount;	/* (a) Count of sequential accesses. */
181 	off_t		f_nextoff;	/* next expected read/write offset. */
182 	union {
183 		struct cdev_privdata *fvn_cdevpriv;
184 					/* (d) Private data for the cdev. */
185 		struct fadvise_info *fvn_advice;
186 	} f_vnun;
187 	/*
188 	 *  DFLAG_SEEKABLE specific fields
189 	 */
190 	off_t		f_offset;
191 	/*
192 	 * Mandatory Access control information.
193 	 */
194 	void		*f_label;	/* Place-holder for MAC label. */
195 };
196 
197 #define	f_cdevpriv	f_vnun.fvn_cdevpriv
198 #define	f_advice	f_vnun.fvn_advice
199 
200 #define	FOFFSET_LOCKED       0x1
201 #define	FOFFSET_LOCK_WAITING 0x2
202 #define	FDEVFS_VNODE	     0x4
203 
204 #endif /* _KERNEL || _WANT_FILE */
205 
206 /*
207  * Userland version of struct file, for sysctl
208  */
209 struct xfile {
210 	size_t	xf_size;	/* size of struct xfile */
211 	pid_t	xf_pid;		/* owning process */
212 	uid_t	xf_uid;		/* effective uid of owning process */
213 	int	xf_fd;		/* descriptor number */
214 	void	*xf_file;	/* address of struct file */
215 	short	xf_type;	/* descriptor type */
216 	int	xf_count;	/* reference count */
217 	int	xf_msgcount;	/* references from message queue */
218 	off_t	xf_offset;	/* file offset */
219 	void	*xf_data;	/* file descriptor specific data */
220 	void	*xf_vnode;	/* vnode pointer */
221 	u_int	xf_flag;	/* flags (see fcntl.h) */
222 };
223 
224 #ifdef _KERNEL
225 
226 extern struct fileops vnops;
227 extern struct fileops badfileops;
228 extern struct fileops socketops;
229 extern int maxfiles;		/* kernel limit on number of open files */
230 extern int maxfilesperproc;	/* per process limit on number of open files */
231 extern volatile int openfiles;	/* actual number of open files */
232 
233 int fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp);
234 int fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp,
235     u_char *maxprotp, struct file **fpp);
236 int fget_read(struct thread *td, int fd, cap_rights_t *rightsp,
237     struct file **fpp);
238 int fget_write(struct thread *td, int fd, cap_rights_t *rightsp,
239     struct file **fpp);
240 int fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp,
241     int needfcntl, struct file **fpp);
242 int _fdrop(struct file *fp, struct thread *td);
243 
244 fo_rdwr_t	invfo_rdwr;
245 fo_truncate_t	invfo_truncate;
246 fo_ioctl_t	invfo_ioctl;
247 fo_poll_t	invfo_poll;
248 fo_kqfilter_t	invfo_kqfilter;
249 fo_chmod_t	invfo_chmod;
250 fo_chown_t	invfo_chown;
251 fo_sendfile_t	invfo_sendfile;
252 
253 fo_sendfile_t	vn_sendfile;
254 fo_seek_t	vn_seek;
255 fo_fill_kinfo_t	vn_fill_kinfo;
256 int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif);
257 
258 void finit(struct file *, u_int, short, void *, struct fileops *);
259 int fgetvp(struct thread *td, int fd, cap_rights_t *rightsp,
260     struct vnode **vpp);
261 int fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp,
262     struct vnode **vpp);
263 int fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
264     struct filecaps *havecaps, struct vnode **vpp);
265 int fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp,
266     struct vnode **vpp);
267 int fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
268     struct vnode **vpp);
269 
270 int fgetsock(struct thread *td, int fd, cap_rights_t *rightsp,
271     struct socket **spp, u_int *fflagp);
272 void fputsock(struct socket *sp);
273 
274 static __inline int
275 _fnoop(void)
276 {
277 
278 	return (0);
279 }
280 
281 #define	fhold(fp)							\
282 	(refcount_acquire(&(fp)->f_count))
283 #define	fdrop(fp, td)							\
284 	(refcount_release(&(fp)->f_count) ? _fdrop((fp), (td)) : _fnoop())
285 
286 static __inline fo_rdwr_t	fo_read;
287 static __inline fo_rdwr_t	fo_write;
288 static __inline fo_truncate_t	fo_truncate;
289 static __inline fo_ioctl_t	fo_ioctl;
290 static __inline fo_poll_t	fo_poll;
291 static __inline fo_kqfilter_t	fo_kqfilter;
292 static __inline fo_stat_t	fo_stat;
293 static __inline fo_close_t	fo_close;
294 static __inline fo_chmod_t	fo_chmod;
295 static __inline fo_chown_t	fo_chown;
296 static __inline fo_sendfile_t	fo_sendfile;
297 
298 static __inline int
299 fo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
300     int flags, struct thread *td)
301 {
302 
303 	return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
304 }
305 
306 static __inline int
307 fo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
308     int flags, struct thread *td)
309 {
310 
311 	return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
312 }
313 
314 static __inline int
315 fo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
316     struct thread *td)
317 {
318 
319 	return ((*fp->f_ops->fo_truncate)(fp, length, active_cred, td));
320 }
321 
322 static __inline int
323 fo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
324     struct thread *td)
325 {
326 
327 	return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
328 }
329 
330 static __inline int
331 fo_poll(struct file *fp, int events, struct ucred *active_cred,
332     struct thread *td)
333 {
334 
335 	return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
336 }
337 
338 static __inline int
339 fo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
340     struct thread *td)
341 {
342 
343 	return ((*fp->f_ops->fo_stat)(fp, sb, active_cred, td));
344 }
345 
346 static __inline int
347 fo_close(struct file *fp, struct thread *td)
348 {
349 
350 	return ((*fp->f_ops->fo_close)(fp, td));
351 }
352 
353 static __inline int
354 fo_kqfilter(struct file *fp, struct knote *kn)
355 {
356 
357 	return ((*fp->f_ops->fo_kqfilter)(fp, kn));
358 }
359 
360 static __inline int
361 fo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
362     struct thread *td)
363 {
364 
365 	return ((*fp->f_ops->fo_chmod)(fp, mode, active_cred, td));
366 }
367 
368 static __inline int
369 fo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
370     struct thread *td)
371 {
372 
373 	return ((*fp->f_ops->fo_chown)(fp, uid, gid, active_cred, td));
374 }
375 
376 static __inline int
377 fo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
378     struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
379     struct thread *td)
380 {
381 
382 	return ((*fp->f_ops->fo_sendfile)(fp, sockfd, hdr_uio, trl_uio, offset,
383 	    nbytes, sent, flags, td));
384 }
385 
386 static __inline int
387 fo_seek(struct file *fp, off_t offset, int whence, struct thread *td)
388 {
389 
390 	return ((*fp->f_ops->fo_seek)(fp, offset, whence, td));
391 }
392 
393 static __inline int
394 fo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
395 {
396 
397 	return ((*fp->f_ops->fo_fill_kinfo)(fp, kif, fdp));
398 }
399 
400 static __inline int
401 fo_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
402     vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
403     struct thread *td)
404 {
405 
406 	if (fp->f_ops->fo_mmap == NULL)
407 		return (ENODEV);
408 	return ((*fp->f_ops->fo_mmap)(fp, map, addr, size, prot, cap_maxprot,
409 	    flags, foff, td));
410 }
411 
412 static __inline int
413 fo_aio_queue(struct file *fp, struct kaiocb *job)
414 {
415 
416 	return ((*fp->f_ops->fo_aio_queue)(fp, job));
417 }
418 
419 #endif /* _KERNEL */
420 
421 #endif /* !SYS_FILE_H */
422