master
1/* $NetBSD: shm.h,v 1.55 2021/08/17 22:00:32 andvar Exp $ */
2
3/*-
4 * Copyright (c) 1999 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33/*
34 * Copyright (c) 1994 Adam Glass
35 * All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. All advertising materials mentioning features or use of this software
46 * must display the following acknowledgement:
47 * This product includes software developed by Adam Glass.
48 * 4. The name of the author may not be used to endorse or promote products
49 * derived from this software without specific prior written permission
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
53 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
54 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
55 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
56 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
60 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62
63/*
64 * As defined+described in "X/Open System Interfaces and Headers"
65 * Issue 4, p. XXX
66 */
67
68#ifndef _SYS_SHM_H_
69#define _SYS_SHM_H_
70
71#include <sys/cdefs.h>
72#include <sys/featuretest.h>
73
74#include <sys/ipc.h>
75
76#define SHM_RDONLY 010000 /* Attach read-only (else read-write) */
77#define SHM_RND 020000 /* Round attach address to SHMLBA */
78#ifdef _KERNEL
79#define _SHM_RMLINGER 040000 /* Attach even if segment removed */
80#endif
81
82/* Segment low boundary address multiple */
83#if defined(_KERNEL) || defined(_STANDALONE) || defined(_MODULE)
84#define SHMLBA PAGE_SIZE
85#else
86/*
87 * SHMLBA uses libc's internal __sysconf() to retrieve the machine's
88 * page size. The value of _SC_PAGESIZE is 28 -- we hard code it so we do not
89 * need to include unistd.h
90 */
91__BEGIN_DECLS
92long __sysconf(int);
93__END_DECLS
94#define SHMLBA (__sysconf(28))
95#endif
96
97typedef unsigned int shmatt_t;
98
99struct shmid_ds {
100 struct ipc_perm shm_perm; /* operation permission structure */
101 size_t shm_segsz; /* size of segment in bytes */
102 pid_t shm_lpid; /* process ID of last shm operation */
103 pid_t shm_cpid; /* process ID of creator */
104 shmatt_t shm_nattch; /* number of current attaches */
105 time_t shm_atime; /* time of last shmat() */
106 time_t shm_dtime; /* time of last shmdt() */
107 time_t shm_ctime; /* time of last change by shmctl() */
108
109 /*
110 * These members are private and used only in the internal
111 * implementation of this interface.
112 */
113 void *_shm_internal;
114};
115
116#if defined(_NETBSD_SOURCE)
117/*
118 * Some systems (e.g. HP-UX) take these as the second (cmd) arg to shmctl().
119 */
120#define SHM_LOCK 3 /* Lock segment in memory. */
121#define SHM_UNLOCK 4 /* Unlock a segment locked by SHM_LOCK. */
122#endif /* _NETBSD_SOURCE */
123
124#if defined(_NETBSD_SOURCE)
125/*
126 * Permission definitions used in shmflag arguments to shmat(2) and shmget(2).
127 * Provided for source compatibility only; do not use in new code!
128 */
129#define SHM_R IPC_R /* S_IRUSR, R for owner */
130#define SHM_W IPC_W /* S_IWUSR, W for owner */
131
132/*
133 * System 5 style catch-all structure for shared memory constants that
134 * might be of interest to user programs. Do we really want/need this?
135 */
136struct shminfo {
137 uint64_t shmmax; /* max shared memory segment size (bytes) */
138 uint32_t shmmin; /* min shared memory segment size (bytes) */
139 uint32_t shmmni; /* max number of shared memory identifiers */
140 uint32_t shmseg; /* max shared memory segments per process */
141 uint32_t shmall; /* max amount of shared memory (pages) */
142};
143
144/* Warning: 64-bit structure padding is needed here */
145struct shmid_ds_sysctl {
146 struct ipc_perm_sysctl shm_perm;
147 uint64_t shm_segsz;
148 pid_t shm_lpid;
149 pid_t shm_cpid;
150 time_t shm_atime;
151 time_t shm_dtime;
152 time_t shm_ctime;
153 uint32_t shm_nattch;
154};
155struct shm_sysctl_info {
156 struct shminfo shminfo;
157 struct shmid_ds_sysctl shmids[1];
158};
159#endif /* _NETBSD_SOURCE */
160
161#ifdef _KERNEL
162extern struct shminfo shminfo;
163extern struct shmid_ds *shmsegs;
164extern int shm_nused;
165
166#define SHMSEG_FREE 0x0200
167#define SHMSEG_REMOVED 0x0400
168#define SHMSEG_ALLOCATED 0x0800
169#define SHMSEG_WANTED 0x1000
170#define SHMSEG_RMLINGER 0x2000
171#define SHMSEG_WIRED 0x4000
172
173struct vmspace;
174
175int shminit(void);
176int shmfini(void);
177void shmfork(struct vmspace *, struct vmspace *);
178void shmexit(struct vmspace *);
179int shmctl1(struct lwp *, int, int, struct shmid_ds *);
180
181int shm_find_segment_perm_by_index(int, struct ipc_perm *);
182
183extern void (*uvm_shmexit)(struct vmspace *);
184extern void (*uvm_shmfork)(struct vmspace *, struct vmspace *);
185
186#define SYSCTL_FILL_SHM(src, dst) do { \
187 SYSCTL_FILL_PERM((src).shm_perm, (dst).shm_perm); \
188 (dst).shm_segsz = (src).shm_segsz; \
189 (dst).shm_lpid = (src).shm_lpid; \
190 (dst).shm_cpid = (src).shm_cpid; \
191 (dst).shm_atime = (src).shm_atime; \
192 (dst).shm_dtime = (src).shm_dtime; \
193 (dst).shm_ctime = (src).shm_ctime; \
194 (dst).shm_nattch = (src).shm_nattch; \
195} while (/*CONSTCOND*/ 0)
196
197#else /* !_KERNEL */
198
199__BEGIN_DECLS
200void *shmat(int, const void *, int);
201int shmctl(int, int, struct shmid_ds *) __RENAME(__shmctl50);
202int shmdt(const void *);
203int shmget(key_t, size_t, int);
204__END_DECLS
205
206#endif /* !_KERNEL */
207
208#endif /* !_SYS_SHM_H_ */