]> git.saurik.com Git - apple/xnu.git/blame - bsd/sys/pipe.h
xnu-2050.18.24.tar.gz
[apple/xnu.git] / bsd / sys / pipe.h
CommitLineData
91447636
A
1/*
2 * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved.
3 *
2d21ac55 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
91447636 5 *
2d21ac55
A
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
8f6c56a5 14 *
2d21ac55
A
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5
A
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55
A
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
8f6c56a5 25 *
2d21ac55 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
91447636
A
27 */
28/*
29 * Copyright (c) 1996 John S. Dyson
30 * All rights reserved.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 * notice immediately at the beginning of the file, without modification,
37 * this list of conditions, and the following disclaimer.
38 * 2. Redistributions in binary form must reproduce the above copyright
39 * notice, this list of conditions and the following disclaimer in the
40 * documentation and/or other materials provided with the distribution.
41 * 3. Absolutely no warranty of function or purpose is made by the author
42 * John S. Dyson.
43 * 4. This work was done expressly for inclusion into FreeBSD. Other use
44 * is allowed if this notation is included.
45 * 5. Modifications may be freely made to this file if the above conditions
46 * are met.
47 *
48 * $FreeBSD: src/sys/sys/pipe.h,v 1.24 2003/08/13 20:01:38 alc Exp $
49 */
2d21ac55
A
50/*
51 * NOTICE: This file was modified by SPARTA, Inc. in 2006 to introduce
52 * support for mandatory and extensible security protections. This notice
53 * is included in support of clause 2.2 (b) of the Apple Public License,
54 * Version 2.0.
55 */
91447636
A
56
57#ifndef _SYS_PIPE_H_
58#define _SYS_PIPE_H_
59
60#ifdef KERNEL
61#include <libkern/locks.h>
62#endif
63#include <sys/queue.h> /* for TAILQ macros */
64#include <sys/ev.h>
65#include <sys/cdefs.h>
66
67/*
68 * Pipe buffer size, keep moderate in value, pipes take kva space.
69 */
70#ifndef PIPE_SIZE
71#define PIPE_SIZE 16384
72#endif
73
316670eb
A
74#define PIPE_KVAMAX (1024 * 1024 * 16)
75
91447636
A
76#ifndef BIG_PIPE_SIZE
77#define BIG_PIPE_SIZE (64*1024)
78#endif
79
80#ifndef SMALL_PIPE_SIZE
81#define SMALL_PIPE_SIZE PAGE_SIZE
82#endif
83
84/*
85 * PIPE_MINDIRECT MUST be smaller than PIPE_SIZE and MUST be bigger
86 * than PIPE_BUF.
87 */
88#ifndef PIPE_MINDIRECT
89#define PIPE_MINDIRECT 8192
90#endif
91
92#define PIPENPAGES (BIG_PIPE_SIZE / PAGE_SIZE + 1)
93
94/*
95 * Pipe buffer information.
96 * Separate in, out, cnt are used to simplify calculations.
97 * Buffered write is active when the buffer.cnt field is set.
98 */
99struct pipebuf {
100 u_int cnt; /* number of chars currently in buffer */
101 u_int in; /* in pointer */
102 u_int out; /* out pointer */
103 u_int size; /* size of buffer */
104 caddr_t buffer; /* kva of buffer */
105};
106
107
108#ifdef PIPE_DIRECT
109/*
110 * Information to support direct transfers between processes for pipes.
111 */
91447636
A
112struct pipemapping {
113 vm_offset_t kva; /* kernel virtual address */
114 vm_size_t cnt; /* number of chars in buffer */
115 vm_size_t pos; /* current position of transfer */
116 int npages; /* number of pages */
117 vm_page_t ms[PIPENPAGES]; /* pages in source process */
118};
119#endif
120
121/*
122 * Bits in pipe_state.
123 */
124#define PIPE_ASYNC 0x004 /* Async? I/O. */
125#define PIPE_WANTR 0x008 /* Reader wants some characters. */
126#define PIPE_WANTW 0x010 /* Writer wants space to put characters. */
127#define PIPE_WANT 0x020 /* Pipe is wanted to be run-down. */
128#define PIPE_SEL 0x040 /* Pipe has a select active. */
129#define PIPE_EOF 0x080 /* Pipe is in EOF condition. */
130#define PIPE_LOCKFL 0x100 /* Process has exclusive access to pointers/data. */
131#define PIPE_LWANT 0x200 /* Process wants exclusive access to pointers/data. */
132#define PIPE_DIRECTW 0x400 /* Pipe direct write active. */
133#define PIPE_DIRECTOK 0x800 /* Direct mode ok. */
b0d623f7
A
134#define PIPE_KNOTE 0x1000 /* Pipe has kernel events activated */
135#define PIPE_DRAIN 0x2000 /* Waiting for I/O to drop for a close. Treated like EOF;
136 only separate for easier debugging. */
ebb1b9f4
A
137#define PIPE_WSELECT 0x4000 /* Some thread has done an FWRITE select on the pipe */
138#define PIPE_DEAD 0x8000 /* Pipe is dead and needs garbage collection */
91447636
A
139
140#ifdef KERNEL
2d21ac55
A
141
142struct label;
143
91447636
A
144/*
145 * Per-pipe data structure.
146 * Two of these are linked together to produce bi-directional pipes.
147 */
148struct pipe {
149 struct pipebuf pipe_buffer; /* data storage */
150#ifdef PIPE_DIRECT
151 struct pipemapping pipe_map; /* pipe mapping for direct I/O */
152#endif
153 struct selinfo pipe_sel; /* for compat with select */
154 pid_t pipe_pgid; /* information for async I/O */
155 struct pipe *pipe_peer; /* link with other direction */
156 u_int pipe_state; /* pipe status info */
157 int pipe_busy; /* busy flag, mostly to handle rundown sanely */
91447636
A
158 TAILQ_HEAD(,eventqelt) pipe_evlist;
159 lck_mtx_t *pipe_mtxp; /* shared mutex between both pipes */
2d21ac55
A
160 struct timespec st_atimespec; /* time of last access */
161 struct timespec st_mtimespec; /* time of last data modification */
162 struct timespec st_ctimespec; /* time of last status change */
163 struct label *pipe_label; /* pipe MAC label - shared */
91447636
A
164};
165
166#define PIPE_MTX(pipe) ((pipe)->pipe_mtxp)
167
168#define PIPE_LOCK(pipe) lck_mtx_lock(PIPE_MTX(pipe))
169#define PIPE_UNLOCK(pipe) lck_mtx_unlock(PIPE_MTX(pipe))
170#define PIPE_LOCK_ASSERT(pipe, type) lck_mtx_assert(PIPE_MTX(pipe), (type))
171
172__BEGIN_DECLS
2d21ac55
A
173void pipeinit(void);
174extern int pipe_stat(struct pipe *, void *, int);
91447636
A
175__END_DECLS
176
177#endif /* KERNEL */
178
179#endif /* !_SYS_PIPE_H_ */