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 * @(#)file.h 8.3 (Berkeley) 1/9/95
32 * $FreeBSD$
33 */
34
35 #ifndef _SYS_FILE_H_
36 #define _SYS_FILE_H_
37
38 #ifndef _KERNEL
39 #include <sys/types.h> /* XXX */
40 #include <sys/fcntl.h>
41 #include <sys/unistd.h>
42 #else
43 #include <sys/queue.h>
44 #include <sys/refcount.h>
45 #include <sys/_lock.h>
46 #include <sys/_mutex.h>
47 #include <vm/vm.h>
48
49 struct filedesc;
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_LINUXTFD 14 /* emulation timerfd type */
74
75 #ifdef _KERNEL
76
77 struct file;
78 struct filecaps;
79 struct kaiocb;
80 struct kinfo_file;
81 struct ucred;
82
83 #define FOF_OFFSET 0x01 /* Use the offset in uio argument */
84 #define FOF_NOLOCK 0x02 /* Do not take FOFFSET_LOCK */
85 #define FOF_NEXTOFF_R 0x04 /* Also update f_nextoff[UIO_READ] */
86 #define FOF_NEXTOFF_W 0x08 /* Also update f_nextoff[UIO_WRITE] */
87 #define FOF_NOUPDATE 0x10 /* Do not update f_offset */
88 off_t foffset_lock(struct file *fp, int flags);
89 void foffset_lock_uio(struct file *fp, struct uio *uio, int flags);
90 void foffset_unlock(struct file *fp, off_t val, int flags);
91 void foffset_unlock_uio(struct file *fp, struct uio *uio, int flags);
92
93 static inline off_t
foffset_get(struct file * fp)94 foffset_get(struct file *fp)
95 {
96
97 return (foffset_lock(fp, FOF_NOLOCK));
98 }
99
100 typedef int fo_rdwr_t(struct file *fp, struct uio *uio,
101 struct ucred *active_cred, int flags,
102 struct thread *td);
103 typedef int fo_truncate_t(struct file *fp, off_t length,
104 struct ucred *active_cred, struct thread *td);
105 typedef int fo_ioctl_t(struct file *fp, u_long com, void *data,
106 struct ucred *active_cred, struct thread *td);
107 typedef int fo_poll_t(struct file *fp, int events,
108 struct ucred *active_cred, struct thread *td);
109 typedef int fo_kqfilter_t(struct file *fp, struct knote *kn);
110 typedef int fo_stat_t(struct file *fp, struct stat *sb,
111 struct ucred *active_cred, struct thread *td);
112 typedef int fo_close_t(struct file *fp, struct thread *td);
113 typedef int fo_chmod_t(struct file *fp, mode_t mode,
114 struct ucred *active_cred, struct thread *td);
115 typedef int fo_chown_t(struct file *fp, uid_t uid, gid_t gid,
116 struct ucred *active_cred, struct thread *td);
117 typedef int fo_sendfile_t(struct file *fp, int sockfd, struct uio *hdr_uio,
118 struct uio *trl_uio, off_t offset, size_t nbytes,
119 off_t *sent, int flags, struct thread *td);
120 typedef int fo_seek_t(struct file *fp, off_t offset, int whence,
121 struct thread *td);
122 typedef int fo_fill_kinfo_t(struct file *fp, struct kinfo_file *kif,
123 struct filedesc *fdp);
124 typedef int fo_mmap_t(struct file *fp, vm_map_t map, vm_offset_t *addr,
125 vm_size_t size, vm_prot_t prot, vm_prot_t cap_maxprot,
126 int flags, vm_ooffset_t foff, struct thread *td);
127 typedef int fo_aio_queue_t(struct file *fp, struct kaiocb *job);
128 typedef int fo_add_seals_t(struct file *fp, int flags);
129 typedef int fo_get_seals_t(struct file *fp, int *flags);
130 typedef int fo_fallocate_t(struct file *fp, off_t offset, off_t len,
131 struct thread *td);
132 typedef int fo_flags_t;
133
134 struct fileops {
135 fo_rdwr_t *fo_read;
136 fo_rdwr_t *fo_write;
137 fo_truncate_t *fo_truncate;
138 fo_ioctl_t *fo_ioctl;
139 fo_poll_t *fo_poll;
140 fo_kqfilter_t *fo_kqfilter;
141 fo_stat_t *fo_stat;
142 fo_close_t *fo_close;
143 fo_chmod_t *fo_chmod;
144 fo_chown_t *fo_chown;
145 fo_sendfile_t *fo_sendfile;
146 fo_seek_t *fo_seek;
147 fo_fill_kinfo_t *fo_fill_kinfo;
148 fo_mmap_t *fo_mmap;
149 fo_aio_queue_t *fo_aio_queue;
150 fo_add_seals_t *fo_add_seals;
151 fo_get_seals_t *fo_get_seals;
152 fo_fallocate_t *fo_fallocate;
153 fo_flags_t fo_flags; /* DFLAG_* below */
154 };
155
156 #define DFLAG_PASSABLE 0x01 /* may be passed via unix sockets. */
157 #define DFLAG_SEEKABLE 0x02 /* seekable / nonsequential */
158 #endif /* _KERNEL */
159
160 #if defined(_KERNEL) || defined(_WANT_FILE)
161 /*
162 * Kernel descriptor table.
163 * One entry for each open kernel vnode and socket.
164 *
165 * Below is the list of locks that protects members in struct file.
166 *
167 * (a) f_vnode lock required (shared allows both reads and writes)
168 * (f) updated with atomics and blocking on sleepq
169 * (d) cdevpriv_mtx
170 * none not locked
171 */
172
173 #if __BSD_VISIBLE
174 struct fadvise_info {
175 int fa_advice; /* (f) FADV_* type. */
176 off_t fa_start; /* (f) Region start. */
177 off_t fa_end; /* (f) Region end. */
178 };
179
180 struct file {
181 volatile u_int f_flag; /* see fcntl.h */
182 volatile u_int f_count; /* reference count */
183 void *f_data; /* file descriptor specific data */
184 struct fileops *f_ops; /* File operations */
185 struct vnode *f_vnode; /* NULL or applicable vnode */
186 struct ucred *f_cred; /* associated credentials. */
187 short f_type; /* descriptor type */
188 short f_vnread_flags; /* (f) Sleep lock for f_offset */
189 /*
190 * DTYPE_VNODE specific fields.
191 */
192 union {
193 int16_t f_seqcount[2]; /* (a) Count of seq. reads and writes. */
194 int f_pipegen;
195 };
196 off_t f_nextoff[2]; /* next expected read/write offset. */
197 union {
198 struct cdev_privdata *fvn_cdevpriv;
199 /* (d) Private data for the cdev. */
200 struct fadvise_info *fvn_advice;
201 } f_vnun;
202 /*
203 * DFLAG_SEEKABLE specific fields
204 */
205 off_t f_offset;
206 };
207
208 #define f_cdevpriv f_vnun.fvn_cdevpriv
209 #define f_advice f_vnun.fvn_advice
210
211 #define FOFFSET_LOCKED 0x1
212 #define FOFFSET_LOCK_WAITING 0x2
213 #endif /* __BSD_VISIBLE */
214
215 #endif /* _KERNEL || _WANT_FILE */
216
217 /*
218 * Userland version of struct file, for sysctl
219 */
220 #if __BSD_VISIBLE
221 struct xfile {
222 ksize_t xf_size; /* size of struct xfile */
223 pid_t xf_pid; /* owning process */
224 uid_t xf_uid; /* effective uid of owning process */
225 int xf_fd; /* descriptor number */
226 int _xf_int_pad1;
227 kvaddr_t xf_file; /* address of struct file */
228 short xf_type; /* descriptor type */
229 short _xf_short_pad1;
230 int xf_count; /* reference count */
231 int xf_msgcount; /* references from message queue */
232 int _xf_int_pad2;
233 off_t xf_offset; /* file offset */
234 kvaddr_t xf_data; /* file descriptor specific data */
235 kvaddr_t xf_vnode; /* vnode pointer */
236 u_int xf_flag; /* flags (see fcntl.h) */
237 int _xf_int_pad3;
238 int64_t _xf_int64_pad[6];
239 };
240 #endif /* __BSD_VISIBLE */
241
242 #ifdef _KERNEL
243
244 extern struct fileops vnops;
245 extern struct fileops badfileops;
246 extern struct fileops path_fileops;
247 extern struct fileops socketops;
248 extern int maxfiles; /* kernel limit on number of open files */
249 extern int maxfilesperproc; /* per process limit on number of open files */
250
251 int fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp);
252 int fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp,
253 vm_prot_t *maxprotp, struct file **fpp);
254 int fget_read(struct thread *td, int fd, cap_rights_t *rightsp,
255 struct file **fpp);
256 int fget_write(struct thread *td, int fd, cap_rights_t *rightsp,
257 struct file **fpp);
258 int fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp,
259 int needfcntl, struct file **fpp);
260 int _fdrop(struct file *fp, struct thread *td);
261
262 fo_rdwr_t invfo_rdwr;
263 fo_truncate_t invfo_truncate;
264 fo_ioctl_t invfo_ioctl;
265 fo_poll_t invfo_poll;
266 fo_kqfilter_t invfo_kqfilter;
267 fo_chmod_t invfo_chmod;
268 fo_chown_t invfo_chown;
269 fo_sendfile_t invfo_sendfile;
270 fo_stat_t vn_statfile;
271 fo_sendfile_t vn_sendfile;
272 fo_seek_t vn_seek;
273 fo_fill_kinfo_t vn_fill_kinfo;
274 fo_kqfilter_t vn_kqfilter_opath;
275 int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif);
276
277 void finit(struct file *, u_int, short, void *, struct fileops *);
278 void finit_vnode(struct file *, u_int, void *, struct fileops *);
279 int fgetvp(struct thread *td, int fd, cap_rights_t *rightsp,
280 struct vnode **vpp);
281 int fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp,
282 struct vnode **vpp);
283 int fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
284 struct filecaps *havecaps, struct vnode **vpp);
285 int fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp,
286 struct vnode **vpp);
287 int fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
288 struct vnode **vpp);
289 int fgetvp_lookup_smr(int fd, struct nameidata *ndp, struct vnode **vpp, bool *fsearch);
290 int fgetvp_lookup(int fd, struct nameidata *ndp, struct vnode **vpp);
291
292 static __inline __result_use_check bool
fhold(struct file * fp)293 fhold(struct file *fp)
294 {
295 return (refcount_acquire_checked(&fp->f_count));
296 }
297
298 #define fdrop(fp, td) ({ \
299 struct file *_fp; \
300 int _error; \
301 \
302 _error = 0; \
303 _fp = (fp); \
304 if (__predict_false(refcount_release(&_fp->f_count))) \
305 _error = _fdrop(_fp, td); \
306 _error; \
307 })
308
309 #define fdrop_close(fp, td) ({ \
310 struct file *_fp; \
311 int _error; \
312 \
313 _error = 0; \
314 _fp = (fp); \
315 if (__predict_true(refcount_release(&_fp->f_count))) \
316 _error = _fdrop(_fp, td); \
317 _error; \
318 })
319
320 static __inline fo_rdwr_t fo_read;
321 static __inline fo_rdwr_t fo_write;
322 static __inline fo_truncate_t fo_truncate;
323 static __inline fo_ioctl_t fo_ioctl;
324 static __inline fo_poll_t fo_poll;
325 static __inline fo_kqfilter_t fo_kqfilter;
326 static __inline fo_stat_t fo_stat;
327 static __inline fo_close_t fo_close;
328 static __inline fo_chmod_t fo_chmod;
329 static __inline fo_chown_t fo_chown;
330 static __inline fo_sendfile_t fo_sendfile;
331
332 static __inline int
fo_read(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)333 fo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
334 int flags, struct thread *td)
335 {
336
337 return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
338 }
339
340 static __inline int
fo_write(struct file * fp,struct uio * uio,struct ucred * active_cred,int flags,struct thread * td)341 fo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
342 int flags, struct thread *td)
343 {
344
345 return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
346 }
347
348 static __inline int
fo_truncate(struct file * fp,off_t length,struct ucred * active_cred,struct thread * td)349 fo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
350 struct thread *td)
351 {
352
353 return ((*fp->f_ops->fo_truncate)(fp, length, active_cred, td));
354 }
355
356 static __inline int
fo_ioctl(struct file * fp,u_long com,void * data,struct ucred * active_cred,struct thread * td)357 fo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
358 struct thread *td)
359 {
360
361 return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
362 }
363
364 static __inline int
fo_poll(struct file * fp,int events,struct ucred * active_cred,struct thread * td)365 fo_poll(struct file *fp, int events, struct ucred *active_cred,
366 struct thread *td)
367 {
368
369 return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
370 }
371
372 static __inline int
fo_stat(struct file * fp,struct stat * sb,struct ucred * active_cred,struct thread * td)373 fo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
374 struct thread *td)
375 {
376
377 return ((*fp->f_ops->fo_stat)(fp, sb, active_cred, td));
378 }
379
380 static __inline int
fo_close(struct file * fp,struct thread * td)381 fo_close(struct file *fp, struct thread *td)
382 {
383
384 return ((*fp->f_ops->fo_close)(fp, td));
385 }
386
387 static __inline int
fo_kqfilter(struct file * fp,struct knote * kn)388 fo_kqfilter(struct file *fp, struct knote *kn)
389 {
390
391 return ((*fp->f_ops->fo_kqfilter)(fp, kn));
392 }
393
394 static __inline int
fo_chmod(struct file * fp,mode_t mode,struct ucred * active_cred,struct thread * td)395 fo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
396 struct thread *td)
397 {
398
399 return ((*fp->f_ops->fo_chmod)(fp, mode, active_cred, td));
400 }
401
402 static __inline int
fo_chown(struct file * fp,uid_t uid,gid_t gid,struct ucred * active_cred,struct thread * td)403 fo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
404 struct thread *td)
405 {
406
407 return ((*fp->f_ops->fo_chown)(fp, uid, gid, active_cred, td));
408 }
409
410 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)411 fo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
412 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
413 struct thread *td)
414 {
415
416 return ((*fp->f_ops->fo_sendfile)(fp, sockfd, hdr_uio, trl_uio, offset,
417 nbytes, sent, flags, td));
418 }
419
420 static __inline int
fo_seek(struct file * fp,off_t offset,int whence,struct thread * td)421 fo_seek(struct file *fp, off_t offset, int whence, struct thread *td)
422 {
423
424 return ((*fp->f_ops->fo_seek)(fp, offset, whence, td));
425 }
426
427 static __inline int
fo_fill_kinfo(struct file * fp,struct kinfo_file * kif,struct filedesc * fdp)428 fo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
429 {
430
431 return ((*fp->f_ops->fo_fill_kinfo)(fp, kif, fdp));
432 }
433
434 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)435 fo_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
436 vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
437 struct thread *td)
438 {
439
440 if (fp->f_ops->fo_mmap == NULL)
441 return (ENODEV);
442 return ((*fp->f_ops->fo_mmap)(fp, map, addr, size, prot, cap_maxprot,
443 flags, foff, td));
444 }
445
446 static __inline int
fo_aio_queue(struct file * fp,struct kaiocb * job)447 fo_aio_queue(struct file *fp, struct kaiocb *job)
448 {
449
450 return ((*fp->f_ops->fo_aio_queue)(fp, job));
451 }
452
453 static __inline int
fo_add_seals(struct file * fp,int seals)454 fo_add_seals(struct file *fp, int seals)
455 {
456
457 if (fp->f_ops->fo_add_seals == NULL)
458 return (EINVAL);
459 return ((*fp->f_ops->fo_add_seals)(fp, seals));
460 }
461
462 static __inline int
fo_get_seals(struct file * fp,int * seals)463 fo_get_seals(struct file *fp, int *seals)
464 {
465
466 if (fp->f_ops->fo_get_seals == NULL)
467 return (EINVAL);
468 return ((*fp->f_ops->fo_get_seals)(fp, seals));
469 }
470
471 static __inline int
fo_fallocate(struct file * fp,off_t offset,off_t len,struct thread * td)472 fo_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
473 {
474
475 if (fp->f_ops->fo_fallocate == NULL)
476 return (ENODEV);
477 return ((*fp->f_ops->fo_fallocate)(fp, offset, len, td));
478 }
479
480 #endif /* _KERNEL */
481
482 #endif /* !SYS_FILE_H */
483