osfmk/i386/ldt.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * @OSF_COPYRIGHT@
  32  */
  33 /*
  34  * Mach Operating System
  35  * Copyright (c) 1991,1990 Carnegie Mellon University
  36  * All Rights Reserved.
  37  *
  38  * Permission to use, copy, modify and distribute this software and its
  39  * documentation is hereby granted, provided that both the copyright
  40  * notice and this permission notice appear in all copies of the
  41  * software, derivative works or modified versions, and any portions
  42  * thereof, and that both notices appear in supporting documentation.
  43  *
  44  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  45  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  46  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  47  *
  48  * Carnegie Mellon requests users of this software to return to
  49  *
  50  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  51  *  School of Computer Science
  52  *  Carnegie Mellon University
  53  *  Pittsburgh PA 15213-3890
  54  *
  55  * any improvements or extensions that they make and grant Carnegie Mellon
  56  * the rights to redistribute these changes.
  57  */
  58 /*
  59  */
  60
  61 /*
  62  * "Local" descriptor table.  At the moment, all tasks use the
  63  * same LDT.
  64  */
  65 #include <i386/seg.h>
  66 #include <i386/pmap.h>
  67 #include <mach/i386/vm_types.h>
  68 #include <mach/i386/vm_param.h>
  69
  70 extern int      syscall(void);
  71 extern int      mach_rpc(void);
  72
  73 struct fake_descriptor  ldt[LDTSZ] = {
  74 /*007*/ { (unsigned int)&syscall,
  75           KERNEL_CS,
  76           0,                            /* no parameters */
  77           ACC_P|ACC_PL_U|ACC_CALL_GATE
  78         },                              /* call gate for system calls */
  79 /*00F*/ { (unsigned int)&mach_rpc,
  80           KERNEL_CS,
  81           0,                            /* no parameters */
  82           ACC_P|ACC_PL_U|ACC_CALL_GATE
  83         },                              /* call gate for mach rpc */
  84 /*017*/ { 0,
  85           0xfffff,
  86           SZ_32|SZ_G,
  87           ACC_P|ACC_PL_U|ACC_CODE_R
  88         },                              /* user code segment */
  89 /*01F*/ { 0,
  90           0xfffff,
  91           SZ_32|SZ_G,
  92           ACC_P|ACC_PL_U|ACC_DATA_W
  93         },                              /* user data segment */
  94 /*027*/ { 0,
  95           0xfffff,
  96           SZ_32|SZ_G,
  97           ACC_P|ACC_PL_U|ACC_DATA_W
  98         },                              /* user cthread segment */
  99 // Storage space for user ldt entries we will make room for 10 entries initially
 100 // as we will probably never need many more than that
 101 /*02F*/ { 0, 0, 0, 0},
 102 /*037*/ { 0, 0, 0, 0},
 103 /*03F*/ { 0, 0, 0, 0},
 104 /*047*/ { 0, 0, 0, 0},
 105 /*04F*/ { 0, 0, 0, 0},
 106 /*057*/ { 0, 0, 0, 0},
 107 /*05F*/ { 0, 0, 0, 0},
 108 /*067*/ { 0, 0, 0, 0},
 109 /*06F*/ { 0, 0, 0, 0},
 110 /*077*/ { 0, 0, 0, 0},
 111
 112 };