osfmk/mach/vm_prot.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * HISTORY
  27  *
  28  * Revision 1.1.1.1  1998/09/22 21:05:31  wsanchez
  29  * Import of Mac OS X kernel (~semeria)
  30  *
  31  * Revision 1.1.1.1  1998/03/07 02:25:46  wsanchez
  32  * Import of OSF Mach kernel (~mburg)
  33  *
  34  * Revision 1.3.8.1  1994/09/23  02:44:31  ezf
  35  *      change marker to not FREE
  36  *      [1994/09/22  21:43:46  ezf]
  37  *
  38  * Revision 1.3.2.2  1993/06/09  02:44:23  gm
  39  *      Added to OSF/1 R1.3 from NMK15.0.
  40  *      [1993/06/02  21:18:51  jeffc]
  41  *
  42  * Revision 1.3  1993/04/19  16:40:48  devrcs
  43  *      make endif tags ansi compliant/include files
  44  *      [1993/02/20  21:45:25  david]
  45  *
  46  * Revision 1.2  1992/12/07  21:29:28  robert
  47  *      integrate any changes below for 14.0 (branch from 13.16 base)
  48  *
  49  *      Joseph Barrera (jsb) at Carnegie-Mellon University 05-Aug-92
  50  *      Added VM_PROT_WANTS_COPY to solve copy-call race condition.
  51  *      [1992/12/06  20:25:47  robert]
  52  *
  53  * Revision 1.1  1992/09/30  02:32:28  robert
  54  *      Initial revision
  55  *
  56  * $EndLog$
  57  */
  58 /* CMU_HIST */
  59 /*
  60  * Revision 2.4.3.1  92/03/03  16:22:41  jeffreyh
  61  *      [David L. Black 92/02/22  17:03:43  dlb@osf.org]
  62  *         Add no change protection value for memory_object_lock_request.
  63  *
  64  * Revision 2.4  91/05/14  17:03:00  mrt
  65  *      Correcting copyright
  66  *
  67  * Revision 2.3  91/02/05  17:37:38  mrt
  68  *      Changed to new Mach copyright
  69  *      [91/02/01  17:22:39  mrt]
  70  *
  71  * Revision 2.2  90/01/22  23:05:57  af
  72  *      Removed execute permission from default protection.
  73  *      On the only machine that cares for execute permission (mips)
  74  *      this is an expensive liability: it requires keeping
  75  *      Icache consistent memory that never contains code.
  76  *      [89/12/15            af]
  77  *
  78  * Revision 2.1  89/08/03  16:06:47  rwd
  79  * Created.
  80  *
  81  * Revision 2.3  89/02/25  18:42:29  gm0w
  82  *      Changes for cleanup.
  83  *
  84  *  6-Jun-85  Avadis Tevanian (avie) at Carnegie-Mellon University
  85  *      Created.
  86  *
  87  */
  88 /* CMU_ENDHIST */
  89 /*
  90  * Mach Operating System
  91  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
  92  * All Rights Reserved.
  93  *
  94  * Permission to use, copy, modify and distribute this software and its
  95  * documentation is hereby granted, provided that both the copyright
  96  * notice and this permission notice appear in all copies of the
  97  * software, derivative works or modified versions, and any portions
  98  * thereof, and that both notices appear in supporting documentation.
  99  *
 100  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 101  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 102  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 103  *
 104  * Carnegie Mellon requests users of this software to return to
 105  *
 106  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 107  *  School of Computer Science
 108  *  Carnegie Mellon University
 109  *  Pittsburgh PA 15213-3890
 110  *
 111  * any improvements or extensions that they make and grant Carnegie Mellon
 112  * the rights to redistribute these changes.
 113  */
 114 /*
 115  */
 116 /*
 117  *      File:   mach/vm_prot.h
 118  *      Author: Avadis Tevanian, Jr., Michael Wayne Young
 119  *
 120  *      Virtual memory protection definitions.
 121  *
 122  */
 123
 124 #ifndef VM_PROT_H_
 125 #define VM_PROT_H_
 126
 127 /*
 128  *      Types defined:
 129  *
 130  *      vm_prot_t               VM protection values.
 131  */
 132
 133 typedef int             vm_prot_t;
 134
 135 /*
 136  *      Protection values, defined as bits within the vm_prot_t type
 137  */
 138
 139 #define VM_PROT_NONE    ((vm_prot_t) 0x00)
 140
 141 #define VM_PROT_READ    ((vm_prot_t) 0x01)      /* read permission */
 142 #define VM_PROT_WRITE   ((vm_prot_t) 0x02)      /* write permission */
 143 #define VM_PROT_EXECUTE ((vm_prot_t) 0x04)      /* execute permission */
 144
 145 /*
 146  *      The default protection for newly-created virtual memory
 147  */
 148
 149 #define VM_PROT_DEFAULT (VM_PROT_READ|VM_PROT_WRITE)
 150
 151 /*
 152  *      The maximum privileges possible, for parameter checking.
 153  */
 154
 155 #define VM_PROT_ALL     (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)
 156
 157 /*
 158  *      An invalid protection value.
 159  *      Used only by memory_object_lock_request to indicate no change
 160  *      to page locks.  Using -1 here is a bad idea because it
 161  *      looks like VM_PROT_ALL and then some.
 162  */
 163 #define VM_PROT_NO_CHANGE       ((vm_prot_t) 0x08)
 164
 165 /*
 166  *      When a caller finds that he cannot obtain write permission on a
 167  *      mapped entry, the following flag can be used.  The entry will
 168  *      be made "needs copy" effectively copying the object (using COW),
 169  *      and write permission will be added to the maximum protections
 170  *      for the associated entry.
 171  */
 172 #define VM_PROT_COPY            ((vm_prot_t) 0x10)
 173
 174
 175 /*
 176  *      Another invalid protection value.
 177  *      Used only by memory_object_data_request upon an object
 178  *      which has specified a copy_call copy strategy. It is used
 179  *      when the kernel wants a page belonging to a copy of the
 180  *      object, and is only asking the object as a result of
 181  *      following a shadow chain. This solves the race between pages
 182  *      being pushed up by the memory manager and the kernel
 183  *      walking down the shadow chain.
 184  */
 185 #define VM_PROT_WANTS_COPY      ((vm_prot_t) 0x10)
 186
 187 #endif  /* VM_PROT_H_ */