osfmk/ipc/ipc_space.h

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
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   8  * Version 2.0 (the 'License'). You may not use this file except in
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  10  * may not be used to create, or enable the creation or redistribution of,
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  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
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  * NOTICE: This file was modified by McAfee Research in 2004 to introduce
  58  * support for mandatory and extensible security protections.  This notice
  59  * is included in support of clause 2.2 (b) of the Apple Public License,
  60  * Version 2.0.
  61  */
  62 /*
  63  */
  64 /*
  65  *      File:   ipc/ipc_space.h
  66  *      Author: Rich Draves
  67  *      Date:   1989
  68  *
  69  *      Definitions for IPC spaces of capabilities.
  70  */
  71
  72 #ifndef _IPC_IPC_SPACE_H_
  73 #define _IPC_IPC_SPACE_H_
  74
  75
  76 #include <mach/mach_types.h>
  77 #include <mach/boolean.h>
  78 #include <mach/kern_return.h>
  79 #include <mach/vm_types.h>
  80
  81 #include <sys/appleapiopts.h>
  82
  83 #ifdef __APPLE_API_PRIVATE
  84 #if MACH_KERNEL_PRIVATE
  85 #include <kern/macro_help.h>
  86 #include <kern/kern_types.h>
  87 #include <kern/locks.h>
  88 #include <kern/task.h>
  89 #include <kern/zalloc.h>
  90 #include <ipc/ipc_entry.h>
  91 #include <ipc/ipc_types.h>
  92
  93 #include <libkern/OSAtomic.h>
  94
  95 /*
  96  *      Every task has a space of IPC capabilities.
  97  *      IPC operations like send and receive use this space.
  98  *      IPC kernel calls manipulate the space of the target task.
  99  *
 100  *      Every space has a non-NULL is_table with is_table_size entries.
 101  *
 102  *      Only one thread can be growing the space at a time.  Others
 103  *      that need it grown wait for the first.  We do almost all the
 104  *      work with the space unlocked, so lookups proceed pretty much
 105  *      unaffected while the grow operation is underway.
 106  */
 107
 108 typedef natural_t ipc_space_refs_t;
 109 #define IS_REFS_MAX     0x0fffffff
 110 #define IS_INACTIVE     0x40000000      /* space is inactive */
 111 #define IS_GROWING      0x20000000      /* space is growing */
 112
 113 struct ipc_space {
 114         lck_spin_t      is_lock_data;
 115         ipc_space_refs_t is_bits;       /* holds refs, active, growing */
 116         ipc_entry_num_t is_table_size;  /* current size of table */
 117         ipc_entry_num_t is_table_free;  /* count of free elements */
 118         ipc_entry_t is_table;           /* an array of entries */
 119         task_t is_task;                 /* associated task */
 120         struct ipc_table_size *is_table_next; /* info for larger table */
 121         ipc_entry_num_t is_low_mod;     /* lowest modified entry during growth */
 122         ipc_entry_num_t is_high_mod;    /* highest modified entry during growth */
 123 };
 124
 125 #define IS_NULL                 ((ipc_space_t) 0)
 126
 127 #define is_active(is)           (((is)->is_bits & IS_INACTIVE) != IS_INACTIVE)
 128
 129 static inline void
 130 is_mark_inactive(ipc_space_t is)
 131 {
 132         assert(is_active(is));
 133         OSBitOrAtomic(IS_INACTIVE, &is->is_bits);
 134 }
 135
 136 #define is_growing(is)          (((is)->is_bits & IS_GROWING) == IS_GROWING)
 137
 138 static inline void
 139 is_start_growing(ipc_space_t is)
 140 {
 141         assert(!is_growing(is));
 142         OSBitOrAtomic(IS_GROWING, &is->is_bits);
 143 }
 144
 145 static inline void
 146 is_done_growing(ipc_space_t is)
 147 {
 148         assert(is_growing(is));
 149         OSBitAndAtomic(~IS_GROWING, &is->is_bits);
 150 }
 151
 152 extern zone_t ipc_space_zone;
 153
 154 #define is_alloc()              ((ipc_space_t) zalloc(ipc_space_zone))
 155 #define is_free(is)             zfree(ipc_space_zone, (is))
 156
 157 extern ipc_space_t ipc_space_kernel;
 158 extern ipc_space_t ipc_space_reply;
 159 #if     DIPC
 160 extern ipc_space_t ipc_space_remote;
 161 #endif  /* DIPC */
 162 #if     DIPC
 163 extern ipc_space_t default_pager_space;
 164 #endif  /* DIPC */
 165
 166 extern lck_grp_t        ipc_lck_grp;
 167 extern lck_attr_t       ipc_lck_attr;
 168
 169 #define is_lock_init(is)        lck_spin_init(&(is)->is_lock_data, &ipc_lck_grp, &ipc_lck_attr)
 170 #define is_lock_destroy(is)     lck_spin_destroy(&(is)->is_lock_data, &ipc_lck_grp)
 171
 172 #define is_read_lock(is)        lck_spin_lock(&(is)->is_lock_data)
 173 #define is_read_unlock(is)      lck_spin_unlock(&(is)->is_lock_data)
 174 #define is_read_sleep(is)       lck_spin_sleep(&(is)->is_lock_data,     \
 175                                                         LCK_SLEEP_DEFAULT,                                      \
 176                                                         (event_t)(is),                                          \
 177                                                         THREAD_UNINT)
 178
 179 #define is_write_lock(is)       lck_spin_lock(&(is)->is_lock_data)
 180 #define is_write_lock_try(is)   lck_spin_try_lock(&(is)->is_lock_data)
 181 #define is_write_unlock(is)     lck_spin_unlock(&(is)->is_lock_data)
 182 #define is_write_sleep(is)      lck_spin_sleep(&(is)->is_lock_data,     \
 183                                                         LCK_SLEEP_DEFAULT,                                      \
 184                                                         (event_t)(is),                                          \
 185                                                         THREAD_UNINT)
 186
 187 #define is_refs(is)             ((is)->is_bits & IS_REFS_MAX)
 188
 189 static inline void
 190 is_reference(ipc_space_t is)
 191 {
 192         assert(is_refs(is) > 0 && is_refs(is) < IS_REFS_MAX);
 193         OSIncrementAtomic(&(is->is_bits));
 194 }
 195
 196
 197 static inline void
 198 is_release(ipc_space_t is) {
 199         assert(is_refs(is) > 0);
 200
 201         /* If we just removed the last reference count */
 202         if ( 1 == (OSDecrementAtomic(&(is->is_bits)) & IS_REFS_MAX)) {
 203                 assert(!is_active(is));
 204                 is_lock_destroy(is);
 205                 is_free(is);
 206         }
 207 }
 208
 209 #define current_space_fast()    (current_task_fast()->itk_space)
 210 #define current_space()         (current_space_fast())
 211
 212 /* Create a special IPC space */
 213 extern kern_return_t ipc_space_create_special(
 214         ipc_space_t     *spacep);
 215
 216 /* Create  new IPC space */
 217 extern kern_return_t ipc_space_create(
 218         ipc_table_size_t        initial,
 219         ipc_space_t             *spacep);
 220
 221 /* Mark a space as dead and cleans up the entries*/
 222 extern void ipc_space_terminate(
 223         ipc_space_t     space);
 224
 225 /* Clean up the entries - but leave the space alive */
 226 extern void ipc_space_clean(
 227         ipc_space_t     space);
 228
 229 #endif /* MACH_KERNEL_PRIVATE */
 230 #endif /* __APPLE_API_PRIVATE */
 231
 232 #ifdef  __APPLE_API_UNSTABLE
 233 #ifndef MACH_KERNEL_PRIVATE
 234
 235 extern ipc_space_t              current_space(void);
 236
 237 #endif /* !MACH_KERNEL_PRIVATE */
 238 #endif /* __APPLE_API_UNSTABLE */
 239
 240 /* Take a reference on a space */
 241 extern void ipc_space_reference(
 242         ipc_space_t     space);
 243
 244 /* Realase a reference on a space */
 245 extern void ipc_space_release(
 246         ipc_space_t     space);
 247
 248 #endif  /* _IPC_IPC_SPACE_H_ */