xref: /NextBSD/sys/sys/file.h (revision 84d351007654069f9643c8e4b4802a7f5f08ee42)
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 #define	DTYPE_MACH_IPC	14	/* port or portset */
72 
73 #ifdef _KERNEL
74 
75 struct file;
76 struct filecaps;
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
foffset_get(struct file * fp)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, int kflags, 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_flags_t;
124 
125 struct fileops {
126 	fo_rdwr_t	*fo_read;
127 	fo_rdwr_t	*fo_write;
128 	fo_truncate_t	*fo_truncate;
129 	fo_ioctl_t	*fo_ioctl;
130 	fo_poll_t	*fo_poll;
131 	fo_kqfilter_t	*fo_kqfilter;
132 	fo_stat_t	*fo_stat;
133 	fo_close_t	*fo_close;
134 	fo_chmod_t	*fo_chmod;
135 	fo_chown_t	*fo_chown;
136 	fo_sendfile_t	*fo_sendfile;
137 	fo_seek_t	*fo_seek;
138 	fo_fill_kinfo_t	*fo_fill_kinfo;
139 	fo_mmap_t	*fo_mmap;
140 	fo_flags_t	fo_flags;	/* DFLAG_* below */
141 };
142 
143 #define DFLAG_PASSABLE	0x01	/* may be passed via unix sockets. */
144 #define DFLAG_SEEKABLE	0x02	/* seekable / nonsequential */
145 #endif /* _KERNEL */
146 
147 #if defined(_KERNEL) || defined(_WANT_FILE)
148 /*
149  * Kernel descriptor table.
150  * One entry for each open kernel vnode and socket.
151  *
152  * Below is the list of locks that protects members in struct file.
153  *
154  * (a) f_vnode lock required (shared allows both reads and writes)
155  * (f) protected with mtx_lock(mtx_pool_find(fp))
156  * (d) cdevpriv_mtx
157  * none	not locked
158  */
159 
160 struct fadvise_info {
161 	int		fa_advice;	/* (f) FADV_* type. */
162 	off_t		fa_start;	/* (f) Region start. */
163 	off_t		fa_end;		/* (f) Region end. */
164 };
165 
166 struct file {
167 	void		*f_data;	/* file descriptor specific data */
168 	struct fileops	*f_ops;		/* File operations */
169 	struct ucred	*f_cred;	/* associated credentials. */
170 	struct vnode 	*f_vnode;	/* NULL or applicable vnode */
171 	short		f_type;		/* descriptor type */
172 	short		f_vnread_flags; /* (f) Sleep lock for f_offset */
173 	volatile u_int	f_flag;		/* see fcntl.h */
174 	volatile u_int 	f_count;	/* reference count */
175 	/*
176 	 *  DTYPE_VNODE specific fields.
177 	 */
178 	int		f_seqcount;	/* (a) Count of sequential accesses. */
179 	off_t		f_nextoff;	/* next expected read/write offset. */
180 	union {
181 		struct cdev_privdata *fvn_cdevpriv;
182 					/* (d) Private data for the cdev. */
183 		struct fadvise_info *fvn_advice;
184 	} f_vnun;
185 	/*
186 	 *  DFLAG_SEEKABLE specific fields
187 	 */
188 	off_t		f_offset;
189 	/*
190 	 * Mandatory Access control information.
191 	 */
192 	void		*f_label;	/* Place-holder for MAC label. */
193 };
194 
195 #define	f_cdevpriv	f_vnun.fvn_cdevpriv
196 #define	f_advice	f_vnun.fvn_advice
197 
198 #define	FOFFSET_LOCKED       0x1
199 #define	FOFFSET_LOCK_WAITING 0x2
200 #define	FDEVFS_VNODE	     0x4
201 
202 #endif /* _KERNEL || _WANT_FILE */
203 
204 /*
205  * Userland version of struct file, for sysctl
206  */
207 struct xfile {
208 	size_t	xf_size;	/* size of struct xfile */
209 	pid_t	xf_pid;		/* owning process */
210 	uid_t	xf_uid;		/* effective uid of owning process */
211 	int	xf_fd;		/* descriptor number */
212 	void	*xf_file;	/* address of struct file */
213 	short	xf_type;	/* descriptor type */
214 	int	xf_count;	/* reference count */
215 	int	xf_msgcount;	/* references from message queue */
216 	off_t	xf_offset;	/* file offset */
217 	void	*xf_data;	/* file descriptor specific data */
218 	void	*xf_vnode;	/* vnode pointer */
219 	u_int	xf_flag;	/* flags (see fcntl.h) */
220 };
221 
222 #ifdef _KERNEL
223 
224 extern struct fileops vnops;
225 extern struct fileops badfileops;
226 extern struct fileops socketops;
227 extern int maxfiles;		/* kernel limit on number of open files */
228 extern int maxfilesperproc;	/* per process limit on number of open files */
229 extern volatile int openfiles;	/* actual number of open files */
230 
231 int fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp);
232 int fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp,
233     u_char *maxprotp, struct file **fpp);
234 int fget_read(struct thread *td, int fd, cap_rights_t *rightsp,
235     struct file **fpp);
236 int fget_write(struct thread *td, int fd, cap_rights_t *rightsp,
237     struct file **fpp);
238 int fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp,
239     int needfcntl, struct file **fpp);
240 int _fdrop(struct file *fp, struct thread *td);
241 
242 fo_rdwr_t	invfo_rdwr;
243 fo_truncate_t	invfo_truncate;
244 fo_ioctl_t	invfo_ioctl;
245 fo_poll_t	invfo_poll;
246 fo_kqfilter_t	invfo_kqfilter;
247 fo_chmod_t	invfo_chmod;
248 fo_chown_t	invfo_chown;
249 fo_sendfile_t	invfo_sendfile;
250 
251 fo_sendfile_t	vn_sendfile;
252 fo_seek_t	vn_seek;
253 fo_fill_kinfo_t	vn_fill_kinfo;
254 int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif);
255 
256 void finit(struct file *, u_int, short, void *, struct fileops *);
257 int fgetvp(struct thread *td, int fd, cap_rights_t *rightsp,
258     struct vnode **vpp);
259 int fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp,
260     struct vnode **vpp);
261 int fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
262     struct filecaps *havecaps, struct vnode **vpp);
263 int fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp,
264     struct vnode **vpp);
265 int fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
266     struct vnode **vpp);
267 
268 int fgetsock(struct thread *td, int fd, cap_rights_t *rightsp,
269     struct socket **spp, u_int *fflagp);
270 void fputsock(struct socket *sp);
271 
272 static __inline int
_fnoop(void)273 _fnoop(void)
274 {
275 
276 	return (0);
277 }
278 
279 #define	fhold(fp)							\
280 	(refcount_acquire(&(fp)->f_count))
281 #define	fdrop(fp, td)							\
282 	(refcount_release(&(fp)->f_count) ? _fdrop((fp), (td)) : _fnoop())
283 
284 static __inline fo_rdwr_t	fo_read;
285 static __inline fo_rdwr_t	fo_write;
286 static __inline fo_truncate_t	fo_truncate;
287 static __inline fo_ioctl_t	fo_ioctl;
288 static __inline fo_poll_t	fo_poll;
289 static __inline fo_kqfilter_t	fo_kqfilter;
290 static __inline fo_stat_t	fo_stat;
291 static __inline fo_close_t	fo_close;
292 static __inline fo_chmod_t	fo_chmod;
293 static __inline fo_chown_t	fo_chown;
294 static __inline fo_sendfile_t	fo_sendfile;
295 
296 static __inline int
fo_read(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)297 fo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
298     int flags, struct thread *td)
299 {
300 
301 	return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
302 }
303 
304 static __inline int
fo_write(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)305 fo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
306     int flags, struct thread *td)
307 {
308 
309 	return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
310 }
311 
312 static __inline int
fo_truncate(struct file * fp,off_t length,struct ucred * active_cred,struct thread * td)313 fo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
314     struct thread *td)
315 {
316 
317 	return ((*fp->f_ops->fo_truncate)(fp, length, active_cred, td));
318 }
319 
320 static __inline int
fo_ioctl(struct file * fp,u_long com,void * data,struct ucred * active_cred,struct thread * td)321 fo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
322     struct thread *td)
323 {
324 
325 	return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
326 }
327 
328 static __inline int
fo_poll(struct file * fp,int events,struct ucred * active_cred,struct thread * td)329 fo_poll(struct file *fp, int events, struct ucred *active_cred,
330     struct thread *td)
331 {
332 
333 	return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
334 }
335 
336 static __inline int
fo_stat(struct file * fp,struct stat * sb,struct ucred * active_cred,struct thread * td)337 fo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
338     struct thread *td)
339 {
340 
341 	return ((*fp->f_ops->fo_stat)(fp, sb, active_cred, td));
342 }
343 
344 static __inline int
fo_close(struct file * fp,struct thread * td)345 fo_close(struct file *fp, struct thread *td)
346 {
347 
348 	return ((*fp->f_ops->fo_close)(fp, td));
349 }
350 
351 static __inline int
fo_kqfilter(struct file * fp,struct knote * kn)352 fo_kqfilter(struct file *fp, struct knote *kn)
353 {
354 
355 	return ((*fp->f_ops->fo_kqfilter)(fp, kn));
356 }
357 
358 static __inline int
fo_chmod(struct file * fp,mode_t mode,struct ucred * active_cred,struct thread * td)359 fo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
360     struct thread *td)
361 {
362 
363 	return ((*fp->f_ops->fo_chmod)(fp, mode, active_cred, td));
364 }
365 
366 static __inline int
fo_chown(struct file * fp,uid_t uid,gid_t gid,struct ucred * active_cred,struct thread * td)367 fo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
368     struct thread *td)
369 {
370 
371 	return ((*fp->f_ops->fo_chown)(fp, uid, gid, active_cred, td));
372 }
373 
374 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,int kflags,struct thread * td)375 fo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
376     struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
377     int kflags, struct thread *td)
378 {
379 
380 	return ((*fp->f_ops->fo_sendfile)(fp, sockfd, hdr_uio, trl_uio, offset,
381 	    nbytes, sent, flags, kflags, td));
382 }
383 
384 static __inline int
fo_seek(struct file * fp,off_t offset,int whence,struct thread * td)385 fo_seek(struct file *fp, off_t offset, int whence, struct thread *td)
386 {
387 
388 	return ((*fp->f_ops->fo_seek)(fp, offset, whence, td));
389 }
390 
391 static __inline int
fo_fill_kinfo(struct file * fp,struct kinfo_file * kif,struct filedesc * fdp)392 fo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
393 {
394 
395 	return ((*fp->f_ops->fo_fill_kinfo)(fp, kif, fdp));
396 }
397 
398 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)399 fo_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
400     vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
401     struct thread *td)
402 {
403 
404 	if (fp->f_ops->fo_mmap == NULL)
405 		return (ENODEV);
406 	return ((*fp->f_ops->fo_mmap)(fp, map, addr, size, prot, cap_maxprot,
407 	    flags, foff, td));
408 }
409 
410 #endif /* _KERNEL */
411 
412 #endif /* !SYS_FILE_H */
413