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 * $FreeBSD$ 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 SEL_RPL_MASK 3 /* requester priv level */ 53 #define ISPL(s) ((s)&3) /* what is the priority level of a selector */ 54 #define SEL_KPL 0 /* kernel priority level */ 55 #define SEL_UPL 3 /* user priority level */ 56 #define ISLDT(s) ((s)&SEL_LDT) /* is it local or global */ 57 #define SEL_LDT 4 /* local descriptor table */ 58 #define IDXSEL(s) (((s)>>3) & 0x1fff) /* index of selector */ 59 #define LSEL(s,r) (((s)<<3) | SEL_LDT | r) /* a local selector */ 60 #define GSEL(s,r) (((s)<<3) | r) /* a global selector */ 61 62 /* 63 * User segment descriptors (%cs, %ds etc for compatability apps. 64 bit wide) 64 * For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl, 65 * sd_p, sd_l and sd_def32 which must be zero). %ds only has sd_p. 66 */ 67 struct user_segment_descriptor { 68 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 69 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 70 u_int64_t sd_type:5; /* segment type */ 71 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 72 u_int64_t sd_p:1; /* segment descriptor present */ 73 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 74 u_int64_t sd_xx:1; /* unused */ 75 u_int64_t sd_long:1; /* long mode (cs only) */ 76 u_int64_t sd_def32:1; /* default 32 vs 16 bit size */ 77 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 78 u_int64_t sd_hibase:8; /* segment base address (msb) */ 79 } __packed; 80 81 /* 82 * System segment descriptors (128 bit wide) 83 */ 84 struct system_segment_descriptor { 85 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 86 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 87 u_int64_t sd_type:5; /* segment type */ 88 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 89 u_int64_t sd_p:1; /* segment descriptor present */ 90 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 91 u_int64_t sd_xx0:3; /* unused */ 92 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 93 u_int64_t sd_hibase:40 __packed;/* segment base address (msb) */ 94 u_int64_t sd_xx1:8; 95 u_int64_t sd_mbz:5; /* MUST be zero */ 96 u_int64_t sd_xx2:19; 97 } __packed; 98 99 /* 100 * Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit) 101 * Only interrupt and trap gates have gd_ist. 102 */ 103 struct gate_descriptor { 104 u_int64_t gd_looffset:16; /* gate offset (lsb) */ 105 u_int64_t gd_selector:16; /* gate segment selector */ 106 u_int64_t gd_ist:3; /* IST table index */ 107 u_int64_t gd_xx:5; /* unused */ 108 u_int64_t gd_type:5; /* segment type */ 109 u_int64_t gd_dpl:2; /* segment descriptor priority level */ 110 u_int64_t gd_p:1; /* segment descriptor present */ 111 u_int64_t gd_hioffset:48 __packed; /* gate offset (msb) */ 112 u_int64_t sd_xx1:32; 113 } __packed; 114 115 /* system segments and gate types */ 116 #define SDT_SYSNULL 0 /* system null */ 117 #define SDT_SYSLDT 2 /* system 64 bit local descriptor table */ 118 #define SDT_SYSTSS 9 /* system available 64 bit TSS */ 119 #define SDT_SYSBSY 11 /* system busy 64 bit TSS */ 120 #define SDT_SYSCGT 12 /* system 64 bit call gate */ 121 #define SDT_SYSIGT 14 /* system 64 bit interrupt gate */ 122 #define SDT_SYSTGT 15 /* system 64 bit trap gate */ 123 124 /* memory segment types */ 125 #define SDT_MEMRO 16 /* memory read only */ 126 #define SDT_MEMROA 17 /* memory read only accessed */ 127 #define SDT_MEMRW 18 /* memory read write */ 128 #define SDT_MEMRWA 19 /* memory read write accessed */ 129 #define SDT_MEMROD 20 /* memory read only expand dwn limit */ 130 #define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 131 #define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 132 #define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 133 #define SDT_MEME 24 /* memory execute only */ 134 #define SDT_MEMEA 25 /* memory execute only accessed */ 135 #define SDT_MEMER 26 /* memory execute read */ 136 #define SDT_MEMERA 27 /* memory execute read accessed */ 137 #define SDT_MEMEC 28 /* memory execute only conforming */ 138 #define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 139 #define SDT_MEMERC 30 /* memory execute read conforming */ 140 #define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 141 142 /* 143 * Software definitions are in this convenient format, 144 * which are translated into inconvenient segment descriptors 145 * when needed to be used by the 386 hardware 146 */ 147 148 struct soft_segment_descriptor { 149 unsigned long ssd_base; /* segment base address */ 150 unsigned long ssd_limit; /* segment extent */ 151 unsigned long ssd_type:5; /* segment type */ 152 unsigned long ssd_dpl:2; /* segment descriptor priority level */ 153 unsigned long ssd_p:1; /* segment descriptor present */ 154 unsigned long ssd_long:1; /* long mode (for %cs) */ 155 unsigned long ssd_def32:1; /* default 32 vs 16 bit size */ 156 unsigned long ssd_gran:1; /* limit granularity (byte/page units)*/ 157 } __packed; 158 159 /* 160 * region descriptors, used to load gdt/idt tables before segments yet exist. 161 */ 162 struct region_descriptor { 163 unsigned long rd_limit:16; /* segment extent */ 164 unsigned long rd_base:64 __packed; /* base address */ 165 } __packed; 166 167 /* 168 * Size of IDT table 169 */ 170 #define NIDT 256 /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */ 171 #define NRSVIDT 32 /* reserved entries for cpu exceptions */ 172 173 /* 174 * Entries in the Interrupt Descriptor Table (IDT) 175 */ 176 #define IDT_DE 0 /* #DE: Divide Error */ 177 #define IDT_DB 1 /* #DB: Debug */ 178 #define IDT_NMI 2 /* Nonmaskable External Interrupt */ 179 #define IDT_BP 3 /* #BP: Breakpoint */ 180 #define IDT_OF 4 /* #OF: Overflow */ 181 #define IDT_BR 5 /* #BR: Bound Range Exceeded */ 182 #define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 183 #define IDT_NM 7 /* #NM: No Math Coprocessor */ 184 #define IDT_DF 8 /* #DF: Double Fault */ 185 #define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 186 #define IDT_TS 10 /* #TS: Invalid TSS */ 187 #define IDT_NP 11 /* #NP: Segment Not Present */ 188 #define IDT_SS 12 /* #SS: Stack Segment Fault */ 189 #define IDT_GP 13 /* #GP: General Protection Fault */ 190 #define IDT_PF 14 /* #PF: Page Fault */ 191 #define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 192 #define IDT_AC 17 /* #AC: Alignment Check */ 193 #define IDT_MC 18 /* #MC: Machine Check */ 194 #define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 195 #define IDT_IO_INTS NRSVIDT /* Base of IDT entries for I/O interrupts. */ 196 #define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */ 197 198 /* 199 * Entries in the Global Descriptor Table (GDT) 200 */ 201 #define GNULL_SEL 0 /* Null Descriptor */ 202 #define GCODE_SEL 1 /* Kernel Code Descriptor */ 203 #define GDATA_SEL 2 /* Kernel Data Descriptor */ 204 #define GUCODE32_SEL 3 /* User 32 bit code Descriptor */ 205 #define GUDATA_SEL 4 /* User 32/64 bit Data Descriptor */ 206 #define GUCODE_SEL 5 /* User 64 bit Code Descriptor */ 207 #define GPROC0_SEL 6 /* TSS for entering kernel etc */ 208 /* slot 6 is second half of GPROC0_SEL */ 209 #define NGDT 8 210 211 #ifdef _KERNEL 212 extern struct user_segment_descriptor gdt[]; 213 extern struct soft_segment_descriptor gdt_segs[]; 214 extern struct gate_descriptor *idt; 215 extern struct region_descriptor r_gdt, r_idt; 216 217 void lgdt(struct region_descriptor *rdp); 218 void sdtossd(struct user_segment_descriptor *sdp, 219 struct soft_segment_descriptor *ssdp); 220 void ssdtosd(struct soft_segment_descriptor *ssdp, 221 struct user_segment_descriptor *sdp); 222 void ssdtosyssd(struct soft_segment_descriptor *ssdp, 223 struct system_segment_descriptor *sdp); 224 #endif /* _KERNEL */ 225 226 #endif /* !_MACHINE_SEGMENTS_H_ */ 227