master
1/* $NetBSD: file.h,v 1.88 2021/09/19 15:51:27 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Copyright (c) 1982, 1986, 1989, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)file.h 8.3 (Berkeley) 1/9/95
61 */
62
63#ifndef _SYS_FILE_H_
64#define _SYS_FILE_H_
65
66#include <sys/fcntl.h>
67#include <sys/unistd.h>
68
69#if defined(_KERNEL) || defined(_KMEMUSER)
70#include <sys/queue.h>
71#include <sys/mutex.h>
72#include <sys/condvar.h>
73
74struct proc;
75struct lwp;
76struct uio;
77struct iovec;
78struct stat;
79struct knote;
80struct uvm_object;
81
82struct fileops {
83 const char *fo_name;
84 int (*fo_read) (struct file *, off_t *, struct uio *,
85 kauth_cred_t, int);
86 int (*fo_write) (struct file *, off_t *, struct uio *,
87 kauth_cred_t, int);
88 int (*fo_ioctl) (struct file *, u_long, void *);
89 int (*fo_fcntl) (struct file *, u_int, void *);
90 int (*fo_poll) (struct file *, int);
91 int (*fo_stat) (struct file *, struct stat *);
92 int (*fo_close) (struct file *);
93 int (*fo_kqfilter) (struct file *, struct knote *);
94 void (*fo_restart) (struct file *);
95 int (*fo_mmap) (struct file *, off_t *, size_t, int, int *,
96 int *, struct uvm_object **, int *);
97 int (*fo_seek) (struct file *, off_t, int, off_t *, int);
98};
99
100union file_data {
101 struct vnode *fd_vp; // DTYPE_VNODE
102 struct socket *fd_so; // DTYPE_SOCKET
103 struct pipe *fd_pipe; // DTYPE_PIPE
104 struct kqueue *fd_kq; // DTYPE_KQUEUE
105 struct eventfd *fd_eventfd; // DTYPE_EVENTFD
106 struct timerfd *fd_timerfd; // DTYPE_TIMERFD
107 void *fd_data; // DTYPE_MISC
108 struct audio_file *fd_audioctx; // DTYPE_MISC (audio)
109 struct pad_softc *fd_pad; // DTYPE_MISC (pad)
110 int fd_devunit; // DTYPE_MISC (tap)
111 struct bpf_d *fd_bpf; // DTYPE_MISC (bpf)
112 struct fcrypt *fd_fcrypt; // DTYPE_CRYPTO is not used
113 struct mqueue *fd_mq; // DTYPE_MQUEUE
114 struct ksem *fd_ks; // DTYPE_SEM
115 struct iscsifd *fd_iscsi; // DTYPE_MISC (iscsi)
116};
117
118/*
119 * Kernel file descriptor. One entry for each open kernel vnode and
120 * socket.
121 *
122 * This structure is exported via the KERN_FILE sysctl.
123 * Only add members to the end, do not delete them.
124 *
125 * Note: new code should not use KERN_FILE; use KERN_FILE2 instead,
126 * which exports struct kinfo_file instead; struct kinfo_file is
127 * declared in sys/sysctl.h and is meant to be ABI-stable.
128 */
129struct file {
130 off_t f_offset; /* first, is 64-bit */
131 kauth_cred_t f_cred; /* creds associated with descriptor */
132 const struct fileops *f_ops;
133 union file_data f_undata; /* descriptor data, e.g. vnode/socket */
134 LIST_ENTRY(file) f_list; /* list of active files */
135 kmutex_t f_lock; /* lock on structure */
136 int f_flag; /* see fcntl.h */
137 u_int f_marker; /* traversal marker (sysctl) */
138 u_int f_type; /* descriptor type */
139 u_int f_advice; /* access pattern hint; UVM_ADV_* */
140 u_int f_count; /* reference count */
141 u_int f_msgcount; /* references from message queue */
142 u_int f_unpcount; /* deferred close: see uipc_usrreq.c */
143 SLIST_ENTRY(file) f_unplist; /* deferred close: see uipc_usrreq.c */
144};
145
146#define f_vnode f_undata.fd_vp
147#define f_socket f_undata.fd_so
148#define f_pipe f_undata.fd_pipe
149#define f_kqueue f_undata.fd_kq
150#define f_data f_undata.fd_data
151#define f_mqueue f_undata.fd_mq
152#define f_ksem f_undata.fd_ks
153#define f_eventfd f_undata.fd_eventfd
154#define f_timerfd f_undata.fd_timerfd
155
156#define f_rndctx f_undata.fd_rndctx
157#define f_audioctx f_undata.fd_audioctx
158#define f_pad f_undata.fd_pad
159#define f_devunit f_undata.fd_devunit
160#define f_bpf f_undata.fd_bpf
161#define f_fcrypt f_undata.fd_fcrypt
162#define f_iscsi f_undata.fd_iscsi
163#endif /* _KERNEL || _KMEMUSER */
164
165/*
166 * Descriptor types.
167 */
168
169#define DTYPE_VNODE 1 /* file */
170#define DTYPE_SOCKET 2 /* communications endpoint */
171#define DTYPE_PIPE 3 /* pipe */
172#define DTYPE_KQUEUE 4 /* event queue */
173#define DTYPE_MISC 5 /* misc file descriptor type */
174#define DTYPE_CRYPTO 6 /* crypto */
175#define DTYPE_MQUEUE 7 /* message queue */
176#define DTYPE_SEM 8 /* semaphore */
177#define DTYPE_EVENTFD 9 /* eventfd */
178#define DTYPE_TIMERFD 10 /* timerfd */
179
180#define DTYPE_NAMES \
181 "0", "file", "socket", "pipe", "kqueue", "misc", "crypto", "mqueue", \
182 "semaphore", "eventfd", "timerfd"
183
184#ifdef _KERNEL
185
186/*
187 * Flags for fo_read and fo_write and do_fileread/write/v
188 */
189#define FOF_UPDATE_OFFSET 0x0001 /* update the file offset */
190#define FOF_IOV_SYSSPACE 0x0100 /* iov structure in kernel memory */
191
192LIST_HEAD(filelist, file);
193extern struct filelist filehead; /* head of list of open files */
194extern u_int maxfiles; /* kernel limit on # of open files */
195
196extern const struct fileops vnops; /* vnode operations for files */
197
198int dofileread(int, struct file *, void *, size_t,
199 off_t *, int, register_t *);
200int dofilewrite(int, struct file *, const void *,
201 size_t, off_t *, int, register_t *);
202
203int do_filereadv(int, const struct iovec *, int, off_t *,
204 int, register_t *);
205int do_filewritev(int, const struct iovec *, int, off_t *,
206 int, register_t *);
207
208int fsetown(pid_t *, u_long, const void *);
209int fgetown(pid_t, u_long, void *);
210void fownsignal(pid_t, int, int, int, void *);
211
212/* Commonly used fileops */
213int fnullop_fcntl(struct file *, u_int, void *);
214int fnullop_poll(struct file *, int);
215int fnullop_kqfilter(struct file *, struct knote *);
216int fbadop_read(struct file *, off_t *, struct uio *, kauth_cred_t, int);
217int fbadop_write(struct file *, off_t *, struct uio *, kauth_cred_t, int);
218int fbadop_ioctl(struct file *, u_long, void *);
219int fbadop_close(struct file *);
220int fbadop_stat(struct file *, struct stat *);
221void fnullop_restart(struct file *);
222
223#endif /* _KERNEL */
224
225#endif /* _SYS_FILE_H_ */