osfmk/i386/user_ldt.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  * Mach Operating System
  27  * Copyright (c) 1991 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 #ifndef _I386_USER_LDT_H_
  55 #define _I386_USER_LDT_H_
  56
  57 /*
  58  * User LDT management.
  59  *
  60  * Each thread in a task may have its own LDT.
  61  */
  62
  63 #include <i386/seg.h>
  64
  65 struct user_ldt {
  66         struct real_descriptor  desc;   /* descriptor for self */
  67         struct real_descriptor  ldt[1]; /* descriptor table (variable) */
  68 };
  69 typedef struct user_ldt *       user_ldt_t;
  70
  71 /*
  72  * Check code/stack/data selector values against LDT if present.
  73  */
  74 #define S_CODE  0               /* code segment */
  75 #define S_STACK 1               /* stack segment */
  76 #define S_DATA  2               /* data segment */
  77
  78 extern boolean_t selector_check(
  79                         thread_t        thread,
  80                         int             sel,
  81                         int             type);
  82 extern void     user_ldt_free(
  83                         user_ldt_t      ldt);
  84
  85 #endif  /* _I386_USER_LDT_H_ */