xref: /xnu-8792.81.2/bsd/sys/sem_internal.h (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)
1 /*
2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
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.
14  *
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
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*
29  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
30  * support for mandatory and extensible security protections.  This notice
31  * is included in support of clause 2.2 (b) of the Apple Public License,
32  * Version 2.0.
33  */
34 /*	$NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $	*/
35 
36 /*
37  * SVID compatible sem_internal.h file
38  *
39  * Author:  Daniel Boulet
40  */
41 /*
42  * John Bellardo modified the implementation for Darwin. 12/2000
43  */
44 
45 #ifndef _SYS_SEM__INTERNALH_
46 #define _SYS_SEM__INTERNALH_
47 
48 #include <sys/sem.h>
49 #include <sys/cdefs.h>
50 
51 
52 /*
53  * This structure is variant for 64 bits because of sem_otime and sem_ctime.
54  */
55 
56 #if __DARWIN_ALIGN_NATURAL
57 #pragma options align=natural
58 #endif
59 
60 struct user_semid_ds {
61 	struct ipc_perm sem_perm;       /* [XSI] operation permission struct */
62 	struct sem      *sem_base;      /* 32 bit base ptr for semaphore set */
63 	unsigned short  sem_nsems;      /* [XSI] number of sems in set */
64 	user_time_t     sem_otime;      /* [XSI] last operation time */
65 	__int32_t       sem_pad1;       /* RESERVED: DO NOT USE! */
66 	user_time_t     sem_ctime;      /* [XSI] last change time */
67 	                                /* Times measured in secs since */
68 	                                /* 00:00:00 GMT, Jan. 1, 1970 */
69 	__int32_t       sem_pad2;       /* RESERVED: DO NOT USE! */
70 	__int32_t       sem_pad3[4];    /* RESERVED: DO NOT USE! */
71 };
72 
73 #pragma pack(4)
74 struct user64_semid_ds {
75 	struct ipc_perm sem_perm;       /* [XSI] operation permission struct */
76 	int32_t sem_base;       /* 32 bit base ptr for semaphore set */
77 	unsigned short  sem_nsems;      /* [XSI] number of sems in set */
78 	user64_time_t   sem_otime;      /* [XSI] last operation time */
79 	int32_t sem_pad1;       /* RESERVED: DO NOT USE! */
80 	user64_time_t   sem_ctime;      /* [XSI] last change time */
81 	                                /* Times measured in secs since */
82 	                                /* 00:00:00 GMT, Jan. 1, 1970 */
83 	int32_t sem_pad2;       /* RESERVED: DO NOT USE! */
84 	int32_t sem_pad3[4];    /* RESERVED: DO NOT USE! */
85 };
86 
87 struct user32_semid_ds {
88 	struct ipc_perm sem_perm;       /* [XSI] operation permission struct */
89 	int32_t sem_base;       /* 32 bit base ptr for semaphore set */
90 	unsigned short  sem_nsems;      /* [XSI] number of sems in set */
91 	user32_time_t   sem_otime;      /* [XSI] last operation time */
92 	int32_t sem_pad1;       /* RESERVED: DO NOT USE! */
93 	user32_time_t   sem_ctime;      /* [XSI] last change time */
94 	                                /* Times measured in secs since */
95 	                                /* 00:00:00 GMT, Jan. 1, 1970 */
96 	int32_t sem_pad2;       /* RESERVED: DO NOT USE! */
97 	int32_t sem_pad3[4];    /* RESERVED: DO NOT USE! */
98 };
99 #pragma pack()
100 
101 union user_semun {
102 	user_addr_t     buf;            /* buffer for IPC_STAT & IPC_SET */
103 	user_addr_t     array;          /* array for GETALL & SETALL */
104 };
105 typedef union user_semun user_semun_t;
106 
107 #if __DARWIN_ALIGN_NATURAL
108 #pragma options align=reset
109 #endif
110 
111 
112 /*
113  * Kernel implementation stuff
114  */
115 #define SEMVMX  32767           /* semaphore maximum value */
116 #define SEMAEM  16384           /* adjust on exit max value */
117 
118 /*
119  * Configuration parameters.  SEMMNI, SEMMNS, and SEMMNU are hard limits.
120  * The code dynamically allocates enough memory to satisfy the current
121  * demand in even increments of SEMMNI_INC, SEMMNS_INC, and SEMMNU_INC.
122  * The code will never allocate more than the hard limits.  The *_INC's
123  * are defined in the kernel section of the header.
124  */
125 /*
126  * Configuration parameters
127  */
128 #ifndef SEMMNS                  /* # of semaphores in system */
129 #define SEMMNS  (1048576/sizeof(struct sem))
130 #endif                          /* no more than 1M of semaphore data */
131 #ifndef SEMMNI                  /* # of semaphore identifiers */
132 #define SEMMNI  SEMMNS          /* max of 1 for each semaphore */
133 #endif
134 #ifndef SEMUME
135 #define SEMUME  10              /* max # of undo entries per process */
136 #endif
137 #ifndef SEMMNU                  /* # of undo structures in system */
138 #define SEMMNU  SEMMNS          /* 1 for each semaphore.  This is quite large */
139 #endif                          /* This should be max 1 for each process */
140 
141 /* shouldn't need tuning */
142 #ifndef SEMMAP
143 #define SEMMAP  30              /* # of entries in semaphore map */
144 #endif
145 #ifndef SEMMSL
146 #define SEMMSL  SEMMNS          /* max # of semaphores per id */
147 #endif
148 #ifndef SEMOPM
149 #define SEMOPM  5               /* max # of operations per semop call */
150 #endif
151 
152 
153 /*
154  * Undo structure (internal: one per process)
155  */
156 struct sem_undo {
157 	int     un_next_idx;    /* index of next active undo structure */
158 	struct  proc *un_proc;          /* owner of this structure */
159 	short   un_cnt;                 /* # of active entries */
160 	struct undo {
161 		short   une_adjval;     /* adjust on exit values */
162 		short   une_num;        /* semaphore # */
163 		int     une_id;         /* semid */
164 		struct undo *une_next;  /* next undo entry */
165 	} *un_ent;                      /* undo entries */
166 };
167 
168 /*
169  * semaphore info struct (internal; for administrative limits and ipcs)
170  */
171 struct seminfo {
172 	int     semmap,         /* # of entries in semaphore map */
173 	    semmni,             /* # of semaphore identifiers */
174 	    semmns,             /* # of semaphores in system */
175 	    semmnu,             /* # of undo structures in system */
176 	    semmsl,             /* max # of semaphores per id */
177 	    semopm,             /* max # of operations per semop call */
178 	    semume,             /* max # of undo entries per process */
179 	    semusz,             /* size in bytes of undo structure */
180 	    semvmx,             /* semaphore maximum value */
181 	    semaem;             /* adjust on exit max value */
182 };
183 extern struct seminfo   seminfo;
184 
185 /*
186  * Kernel wrapper for the user-level structure
187  */
188 struct semid_kernel {
189 	struct  user_semid_ds u;
190 	struct  label *label;   /* MAC framework label */
191 };
192 
193 
194 /* internal "mode" bits */
195 #define SEM_ALLOC       01000   /* semaphore is allocated */
196 #define SEM_DEST        02000   /* semaphore will be destroyed on last detach */
197 
198 #define SEMMNI_INC      32      /* increment value for semaphore identifiers */
199 #define SEMMNS_INC      64      /* increment value for semaphores */
200 #define SEMMNU_INC      32      /* increment value for undo structures */
201 
202 /*
203  * Due to the way semaphore memory is allocated, we have to ensure that
204  * SEMUSZ is properly aligned.
205  *
206  * We are not doing strange semaphore memory allocation anymore, so
207  * these macros are no longer needed.
208  */
209 
210 /*
211  * #define SEM_ALIGN(bytes) (((bytes) + (sizeof(long) - 1)) & ~(sizeof(long) - 1))
212  */
213 
214 /* actual size of an undo structure */
215 /*
216  * #define SEMUSZ	SEM_ALIGN(offsetof(struct sem_undo, un_ent[SEMUME]))
217  */
218 #define SEMUSZ          sizeof(struct sem_undo)
219 
220 /*
221  * Macro to find a particular sem_undo vector
222  */
223 /* Until we can initialize seminfo.semusz to SEMUSZ, we hard code the size macro
224  * in SEMU.  This should be fixed when (if) we implement dynamic pool sizes
225  *
226  * #define SEMU(ix)     ((struct sem_undo *)(((intptr_t)semu)+ix * seminfo.semusz))
227  */
228 /*
229  * This macro doesn't work because we are using a staticly allocated array
230  * for semu now.
231  * #define SEMU(ix)        ((struct sem_undo *)(((intptr_t)semu)+ix * SEMUSZ))
232  */
233 #define SEMU(ix)        (&semu[ix])
234 
235 
236 /*
237  * Process sem_undo vectors at proc exit.
238  */
239 void    semexit(struct proc *p);
240 
241 #endif /* !_SYS_SEM__INTERNALH_ */
242