segments.h revision 120346
1/*- 2 * Copyright (c) 1989, 1990 William F. Jolitz 3 * Copyright (c) 1990 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * William Jolitz. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: @(#)segments.h 7.1 (Berkeley) 5/9/91 38 * $FreeBSD: head/sys/amd64/include/segments.h 120346 2003-09-22 22:09:02Z peter $ 39 */ 40 41#ifndef _MACHINE_SEGMENTS_H_ 42#define _MACHINE_SEGMENTS_H_ 43 44/* 45 * AMD64 Segmentation Data Structures and definitions 46 */ 47 48/* 49 * Selectors 50 */ 51 52#define ISPL(s) ((s)&3) /* what is the priority level of a selector */ 53#define SEL_KPL 0 /* kernel priority level */ 54#define SEL_UPL 3 /* user priority level */ 55#define ISLDT(s) ((s)&SEL_LDT) /* is it local or global */ 56#define SEL_LDT 4 /* local descriptor table */ 57#define IDXSEL(s) (((s)>>3) & 0x1fff) /* index of selector */ 58#define LSEL(s,r) (((s)<<3) | SEL_LDT | r) /* a local selector */ 59#define GSEL(s,r) (((s)<<3) | r) /* a global selector */ 60 61/* 62 * User segment descriptors (%cs, %ds etc for compatability apps. 64 bit wide) 63 * For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl, 64 * sd_p, sd_l and sd_def32 which must be zero). %ds only has sd_p. 65 */ 66struct user_segment_descriptor { 67 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 68 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 69 u_int64_t sd_type:5; /* segment type */ 70 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 71 u_int64_t sd_p:1; /* segment descriptor present */ 72 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 73 u_int64_t sd_xx:1; /* unused */ 74 u_int64_t sd_long:1; /* long mode (cs only) */ 75 u_int64_t sd_def32:1; /* default 32 vs 16 bit size */ 76 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 77 u_int64_t sd_hibase:8; /* segment base address (msb) */ 78} __packed; 79 80/* 81 * System segment descriptors (128 bit wide) 82 */ 83struct system_segment_descriptor { 84 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 85 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 86 u_int64_t sd_type:5; /* segment type */ 87 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 88 u_int64_t sd_p:1; /* segment descriptor present */ 89 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 90 u_int64_t sd_xx0:3; /* unused */ 91 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 92 u_int64_t sd_hibase:40 __packed;/* segment base address (msb) */ 93 u_int64_t sd_xx1:8; 94 u_int64_t sd_mbz:5; /* MUST be zero */ 95 u_int64_t sd_xx2:19; 96} __packed; 97 98/* 99 * Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit) 100 * Only interrupt and trap gates have gd_ist. 101 */ 102struct gate_descriptor { 103 u_int64_t gd_looffset:16; /* gate offset (lsb) */ 104 u_int64_t gd_selector:16; /* gate segment selector */ 105 u_int64_t gd_ist:3; /* IST table index */ 106 u_int64_t gd_xx:5; /* unused */ 107 u_int64_t gd_type:5; /* segment type */ 108 u_int64_t gd_dpl:2; /* segment descriptor priority level */ 109 u_int64_t gd_p:1; /* segment descriptor present */ 110 u_int64_t gd_hioffset:48 __packed; /* gate offset (msb) */ 111 u_int64_t sd_xx1:32; 112} __packed; 113 114 /* system segments and gate types */ 115#define SDT_SYSNULL 0 /* system null */ 116#define SDT_SYSLDT 2 /* system 64 bit local descriptor table */ 117#define SDT_SYSTSS 9 /* system available 64 bit TSS */ 118#define SDT_SYSBSY 11 /* system busy 64 bit TSS */ 119#define SDT_SYSCGT 12 /* system 64 bit call gate */ 120#define SDT_SYSIGT 14 /* system 64 bit interrupt gate */ 121#define SDT_SYSTGT 15 /* system 64 bit trap gate */ 122 123 /* memory segment types */ 124#define SDT_MEMRO 16 /* memory read only */ 125#define SDT_MEMROA 17 /* memory read only accessed */ 126#define SDT_MEMRW 18 /* memory read write */ 127#define SDT_MEMRWA 19 /* memory read write accessed */ 128#define SDT_MEMROD 20 /* memory read only expand dwn limit */ 129#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 130#define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 131#define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 132#define SDT_MEME 24 /* memory execute only */ 133#define SDT_MEMEA 25 /* memory execute only accessed */ 134#define SDT_MEMER 26 /* memory execute read */ 135#define SDT_MEMERA 27 /* memory execute read accessed */ 136#define SDT_MEMEC 28 /* memory execute only conforming */ 137#define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 138#define SDT_MEMERC 30 /* memory execute read conforming */ 139#define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 140 141/* 142 * Software definitions are in this convenient format, 143 * which are translated into inconvenient segment descriptors 144 * when needed to be used by the 386 hardware 145 */ 146 147struct soft_segment_descriptor { 148 unsigned long ssd_base; /* segment base address */ 149 unsigned long ssd_limit; /* segment extent */ 150 unsigned long ssd_type:5; /* segment type */ 151 unsigned long ssd_dpl:2; /* segment descriptor priority level */ 152 unsigned long ssd_p:1; /* segment descriptor present */ 153 unsigned long ssd_long:1; /* long mode (for %cs) */ 154 unsigned long ssd_def32:1; /* default 32 vs 16 bit size */ 155 unsigned long ssd_gran:1; /* limit granularity (byte/page units)*/ 156} __packed; 157 158/* 159 * region descriptors, used to load gdt/idt tables before segments yet exist. 160 */ 161struct region_descriptor { 162 unsigned long rd_limit:16; /* segment extent */ 163 unsigned long rd_base:64 __packed; /* base address */ 164} __packed; 165 166/* 167 * Size of IDT table 168 */ 169#define NIDT 256 /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */ 170#define NRSVIDT 32 /* reserved entries for cpu exceptions */ 171 172/* 173 * Entries in the Interrupt Descriptor Table (IDT) 174 */ 175#define IDT_DE 0 /* #DE: Divide Error */ 176#define IDT_DB 1 /* #DB: Debug */ 177#define IDT_NMI 2 /* Nonmaskable External Interrupt */ 178#define IDT_BP 3 /* #BP: Breakpoint */ 179#define IDT_OF 4 /* #OF: Overflow */ 180#define IDT_BR 5 /* #BR: Bound Range Exceeded */ 181#define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 182#define IDT_NM 7 /* #NM: No Math Coprocessor */ 183#define IDT_DF 8 /* #DF: Double Fault */ 184#define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 185#define IDT_TS 10 /* #TS: Invalid TSS */ 186#define IDT_NP 11 /* #NP: Segment Not Present */ 187#define IDT_SS 12 /* #SS: Stack Segment Fault */ 188#define IDT_GP 13 /* #GP: General Protection Fault */ 189#define IDT_PF 14 /* #PF: Page Fault */ 190#define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 191#define IDT_AC 17 /* #AC: Alignment Check */ 192#define IDT_MC 18 /* #MC: Machine Check */ 193#define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 194#define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */ 195 196/* 197 * Entries in the Global Descriptor Table (GDT) 198 */ 199#define GNULL_SEL 0 /* Null Descriptor */ 200#define GCODE_SEL 1 /* Kernel Code Descriptor */ 201#define GDATA_SEL 2 /* Kernel Data Descriptor */ 202#define GUCODE32_SEL 3 /* User 32 bit code Descriptor */ 203#define GUDATA_SEL 4 /* User 32/64 bit Data Descriptor */ 204#define GUCODE_SEL 5 /* User 64 bit Code Descriptor */ 205#define GPROC0_SEL 6 /* TSS for entering kernel etc */ 206/* slot 6 is second half of GPROC0_SEL */ 207#define NGDT 8 208 209#ifdef _KERNEL 210extern struct user_segment_descriptor gdt[]; 211extern struct soft_segment_descriptor gdt_segs[]; 212extern struct gate_descriptor *idt; 213 214void lgdt(struct region_descriptor *rdp); 215void sdtossd(struct user_segment_descriptor *sdp, 216 struct soft_segment_descriptor *ssdp); 217void ssdtosd(struct soft_segment_descriptor *ssdp, 218 struct user_segment_descriptor *sdp); 219void ssdtosyssd(struct soft_segment_descriptor *ssdp, 220 struct system_segment_descriptor *sdp); 221#endif /* _KERNEL */ 222 223#endif /* !_MACHINE_SEGMENTS_H_ */ 224