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1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
43866e37 6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b 7 *
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8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
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22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25/*
26 * @OSF_COPYRIGHT@
27 */
28/*
29 * Mach Operating System
30 * Copyright (c) 1991,1990 Carnegie Mellon University
31 * All Rights Reserved.
32 *
33 * Permission to use, copy, modify and distribute this software and its
34 * documentation is hereby granted, provided that both the copyright
35 * notice and this permission notice appear in all copies of the
36 * software, derivative works or modified versions, and any portions
37 * thereof, and that both notices appear in supporting documentation.
38 *
39 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
40 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
41 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
42 *
43 * Carnegie Mellon requests users of this software to return to
44 *
45 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
46 * School of Computer Science
47 * Carnegie Mellon University
48 * Pittsburgh PA 15213-3890
49 *
50 * any improvements or extensions that they make and grant Carnegie Mellon
51 * the rights to redistribute these changes.
52 */
53/*
54 */
55
56#ifndef _I386_SEG_H_
57#define _I386_SEG_H_
58#include <mach_kdb.h>
59
60/*
61 * i386 segmentation.
62 */
63
64#ifndef __ASSEMBLER__
65/*
66 * Real segment descriptor.
67 */
68struct real_descriptor {
69 unsigned int limit_low:16, /* limit 0..15 */
70 base_low:16, /* base 0..15 */
71 base_med:8, /* base 16..23 */
72 access:8, /* access byte */
73 limit_high:4, /* limit 16..19 */
74 granularity:4, /* granularity */
75 base_high:8; /* base 24..31 */
76};
77
78struct real_gate {
79 unsigned int offset_low:16, /* offset 0..15 */
80 selector:16,
81 word_count:8,
82 access:8,
83 offset_high:16; /* offset 16..31 */
84};
85
86/*
87 * We build descriptors and gates in a 'fake' format to let the
88 * fields be contiguous. We shuffle them into the real format
89 * at runtime.
90 */
91struct fake_descriptor {
92 unsigned int offset:32; /* offset */
93 unsigned int lim_or_seg:20; /* limit */
94 /* or segment, for gate */
95 unsigned int size_or_wdct:4; /* size/granularity */
96 /* word count, for gate */
97 unsigned int access:8; /* access */
98};
99#endif /*__ASSEMBLER__*/
100
101#define SZ_32 0x4 /* 32-bit segment */
102#define SZ_G 0x8 /* 4K limit field */
103
104#define ACC_A 0x01 /* accessed */
105#define ACC_TYPE 0x1e /* type field: */
106
107#define ACC_TYPE_SYSTEM 0x00 /* system descriptors: */
108
109#define ACC_LDT 0x02 /* LDT */
110#define ACC_CALL_GATE_16 0x04 /* 16-bit call gate */
111#define ACC_TASK_GATE 0x05 /* task gate */
112#define ACC_TSS 0x09 /* task segment */
113#define ACC_CALL_GATE 0x0c /* call gate */
114#define ACC_INTR_GATE 0x0e /* interrupt gate */
115#define ACC_TRAP_GATE 0x0f /* trap gate */
116
117#define ACC_TSS_BUSY 0x02 /* task busy */
118
119#define ACC_TYPE_USER 0x10 /* user descriptors */
120
121#define ACC_DATA 0x10 /* data */
122#define ACC_DATA_W 0x12 /* data, writable */
123#define ACC_DATA_E 0x14 /* data, expand-down */
124#define ACC_DATA_EW 0x16 /* data, expand-down,
125 writable */
126#define ACC_CODE 0x18 /* code */
127#define ACC_CODE_R 0x1a /* code, readable */
128#define ACC_CODE_C 0x1c /* code, conforming */
129#define ACC_CODE_CR 0x1e /* code, conforming,
130 readable */
131#define ACC_PL 0x60 /* access rights: */
132#define ACC_PL_K 0x00 /* kernel access only */
133#define ACC_PL_U 0x60 /* user access */
134#define ACC_P 0x80 /* segment present */
135
136/*
137 * Components of a selector
138 */
139#define SEL_LDTS 0x04 /* local selector */
140#define SEL_PL 0x03 /* privilege level: */
141#define SEL_PL_K 0x00 /* kernel selector */
142#define SEL_PL_U 0x03 /* user selector */
143
144/*
145 * Convert selector to descriptor table index.
146 */
147#define sel_idx(sel) ((sel)>>3)
148
149/*
150 * User descriptors for MACH - 32-bit flat address space
151 */
152#define USER_SCALL 0x07 /* system call gate */
153#define USER_RPC 0x0f /* mach rpc call gate */
154#define USER_CS 0x17 /* user code segment */
155#define USER_DS 0x1f /* user data segment */
55e303ae 156#define USER_CTHREAD 0x27 /* user cthread area */
1c79356b 157
55e303ae 158#define LDTSZ 5
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159
160/*
161 * Kernel descriptors for MACH - 32-bit flat address space.
162 */
163#define KERNEL_CS 0x08 /* kernel code */
164#define KERNEL_DS 0x10 /* kernel data */
165#define KERNEL_LDT 0x18 /* master LDT */
166#define KERNEL_TSS 0x20 /* master TSS (uniprocessor) */
167#ifdef MACH_BSD
168#define BSD_SCALL_SEL 0x28 /* BSD System calls */
169#define MK25_SCALL_SEL 0x30 /* MK25 System Calls */
170#define MACHDEP_SCALL_SEL 0x38 /* Machdep SYstem calls */
171#else
172#define USER_LDT 0x28 /* place for per-thread LDT */
173#define USER_TSS 0x30 /* place for per-thread TSS
174 that holds IO bitmap */
175#define FPE_CS 0x38 /* floating-point emulator code */
176#endif
177#define USER_FPREGS 0x40 /* user-mode access to saved
178 floating-point registers */
179#define CPU_DATA 0x48 /* per-cpu data */
180
181#ifdef MACH_BSD
182#define USER_LDT 0x58
183#define USER_TSS 0x60
184#define FPE_CS 0x68
185#endif
186
187#if MACH_KDB
188#define DEBUG_TSS 0x50 /* debug TSS (uniprocessor) */
189
190#ifdef MACH_BSD
191#define GDTSZ 14
192#else
193#define GDTSZ 11
194#endif
195#else
196
197#ifdef MACH_BSD
198#define GDTSZ 13
199#else
200#define GDTSZ 10
201#endif
202#endif
203
204/*
205 * Interrupt table is always 256 entries long.
206 */
207#define IDTSZ 256
208
209#endif /* _I386_SEG_H_ */