osfmk/i386/ldt.c

   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  * Mach Operating System
  27  * Copyright (c) 1991,1990 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50 /*
  51  */
  52
  53 /*
  54  * "Local" descriptor table.  At the moment, all tasks use the
  55  * same LDT.
  56  */
  57 #include <i386/seg.h>
  58 #include <i386/pmap.h>
  59 #include <mach/i386/vm_types.h>
  60 #include <mach/i386/vm_param.h>
  61
  62 extern int      syscall(void);
  63 extern int      mach_rpc(void);
  64
  65 struct fake_descriptor  ldt[LDTSZ] = {
  66 /*007*/ { (unsigned int)&syscall,
  67           KERNEL_CS,
  68           0,                            /* no parameters */
  69           ACC_P|ACC_PL_U|ACC_CALL_GATE
  70         },                              /* call gate for system calls */
  71 /*00F*/ { (unsigned int)&mach_rpc,
  72           KERNEL_CS,
  73           0,                            /* no parameters */
  74           ACC_P|ACC_PL_U|ACC_CALL_GATE
  75         },                              /* call gate for mach rpc */
  76 /*017*/ { 0,
  77           0xfffff,
  78           SZ_32|SZ_G,
  79           ACC_P|ACC_PL_U|ACC_CODE_R
  80         },                              /* user code segment */
  81 /*01F*/ { 0,
  82           0xfffff,
  83           SZ_32|SZ_G,
  84           ACC_P|ACC_PL_U|ACC_DATA_W
  85         },                              /* user data segment */
  86 /*027*/ { 0,
  87           0xfffff,
  88           SZ_32|SZ_G,
  89           ACC_P|ACC_PL_U|ACC_DATA_W
  90         },                              /* user cthread segment */
  91 // Storage space for user ldt entries we will make room for 10 entries initially
  92 // as we will probably never need many more than that
  93 /*02F*/ { 0, 0, 0, 0},
  94 /*037*/ { 0, 0, 0, 0},
  95 /*03F*/ { 0, 0, 0, 0},
  96 /*047*/ { 0, 0, 0, 0},
  97 /*04F*/ { 0, 0, 0, 0},
  98 /*057*/ { 0, 0, 0, 0},
  99 /*05F*/ { 0, 0, 0, 0},
 100 /*067*/ { 0, 0, 0, 0},
 101 /*06F*/ { 0, 0, 0, 0},
 102 /*077*/ { 0, 0, 0, 0},
 103
 104 };