1 /*- 2 * Copyright (c) 1989, 1990 William F. Jolitz 3 * Copyright (c) 1990 The Regents of the University of California. 4 * Copyright (c) 2008 The DragonFly Project. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: @(#)segments.h 7.1 (Berkeley) 5/9/91 35 * $FreeBSD: src/sys/i386/include/segments.h,v 1.24 1999/12/29 04:33:07 peter Exp $ 36 */ 37 38 #ifndef _CPU_SEGMENTS_H_ 39 #define _CPU_SEGMENTS_H_ 40 41 #ifndef LOCORE 42 #include <sys/tls.h> 43 #endif 44 45 /* 46 * x86_64 Segmentation Data Structures and definitions 47 */ 48 49 /* 50 * Selectors 51 */ 52 53 #define SEL_RPL_MASK 3 /* requester priv level */ 54 #define ISPL(s) ((s)&3) /* what is the privilege level of a selector */ 55 #define SEL_KPL 0 /* kernel privilege level */ 56 #define SEL_UPL 3 /* user privilege level */ 57 #define ISLDT(s) ((s)&SEL_LDT) /* is it local or global */ 58 #define SEL_LDT 4 /* local descriptor table */ 59 #define IDXSEL(s) (((s)>>3) & 0x1fff) /* index of selector */ 60 #define LSEL(s,r) (((s)<<3) | SEL_LDT | r) /* a local selector */ 61 #define GSEL(s,r) (((s)<<3) | r) /* a global selector */ 62 63 #ifndef LOCORE 64 65 /* 66 * User segment descriptors (%cs, %ds etc for compatibility apps. 64 bit wide) 67 * For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl, 68 * sd_p, sd_l and sd_def32 which must be zero). %ds only has sd_p. 69 */ 70 struct user_segment_descriptor { 71 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 72 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 73 u_int64_t sd_type:5; /* segment type */ 74 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 75 u_int64_t sd_p:1; /* segment descriptor present */ 76 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 77 u_int64_t sd_xx:1; /* unused */ 78 u_int64_t sd_long:1; /* long mode (cs only) */ 79 u_int64_t sd_def32:1; /* default 32 vs 16 bit size */ 80 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 81 u_int64_t sd_hibase:8; /* segment base address (msb) */ 82 } __packed; 83 84 /* 85 * System segment descriptors (128 bit wide) 86 */ 87 struct system_segment_descriptor { 88 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 89 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 90 u_int64_t sd_type:5; /* segment type */ 91 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 92 u_int64_t sd_p:1; /* segment descriptor present */ 93 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 94 u_int64_t sd_xx0:3; /* unused */ 95 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 96 u_int64_t sd_hibase:40 __packed;/* segment base address (msb) */ 97 u_int64_t sd_xx1:8; 98 u_int64_t sd_mbz:5; /* MUST be zero */ 99 u_int64_t sd_xx2:19; 100 } __packed; 101 102 /* 103 * Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit) 104 * Only interrupt and trap gates have gd_ist. 105 */ 106 struct gate_descriptor { 107 u_int64_t gd_looffset:16; /* gate offset (lsb) */ 108 u_int64_t gd_selector:16; /* gate segment selector */ 109 u_int64_t gd_ist:3; /* IST table index */ 110 u_int64_t gd_xx:5; /* unused */ 111 u_int64_t gd_type:5; /* segment type */ 112 u_int64_t gd_dpl:2; /* segment descriptor priority level */ 113 u_int64_t gd_p:1; /* segment descriptor present */ 114 u_int64_t gd_hioffset:48 __packed; /* gate offset (msb) */ 115 u_int64_t sd_xx1:32; 116 } __packed; 117 118 #endif /* LOCORE */ 119 120 /* system segments and gate types */ 121 #define SDT_SYSNULL 0 /* system null */ 122 #define SDT_SYSLDT 2 /* system 64-bit local descriptor table */ 123 #define SDT_SYSTSS 9 /* system available 64-bit TSS */ 124 #define SDT_SYSBSY 11 /* system busy 64-bit TSS */ 125 #define SDT_SYSCGT 12 /* system 64-bit call gate */ 126 #define SDT_SYSIGT 14 /* system 64-bit interrupt gate */ 127 #define SDT_SYSTGT 15 /* system 64-bit trap gate */ 128 129 /* memory segment types */ 130 #define SDT_MEMRO 16 /* memory read only */ 131 #define SDT_MEMROA 17 /* memory read only accessed */ 132 #define SDT_MEMRW 18 /* memory read write */ 133 #define SDT_MEMRWA 19 /* memory read write accessed */ 134 #define SDT_MEMROD 20 /* memory read only expand dwn limit */ 135 #define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 136 #define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 137 #define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 138 #define SDT_MEME 24 /* memory execute only */ 139 #define SDT_MEMEA 25 /* memory execute only accessed */ 140 #define SDT_MEMER 26 /* memory execute read */ 141 #define SDT_MEMERA 27 /* memory execute read accessed */ 142 #define SDT_MEMEC 28 /* memory execute only conforming */ 143 #define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 144 #define SDT_MEMERC 30 /* memory execute read conforming */ 145 #define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 146 147 148 #ifndef LOCORE 149 150 struct savetls { 151 struct tls_info info[2]; 152 }; 153 154 /* 155 * Software definitions are in this convenient format, 156 * which are translated into inconvenient segment descriptors 157 * when needed to be used by the x86 hardware. 158 */ 159 160 struct soft_segment_descriptor { 161 uint64_t ssd_base; /* segment base address */ 162 uint64_t ssd_limit; /* segment extent */ 163 uint64_t ssd_type:5; /* segment type */ 164 uint64_t ssd_dpl:2; /* segment descriptor priority level */ 165 uint64_t ssd_p:1; /* segment descriptor present */ 166 uint64_t ssd_long:1; /* long mode (for %cs) */ 167 uint64_t ssd_def32:1; /* default 32 vs 16 bit size */ 168 uint64_t ssd_gran:1; /* limit granularity (byte/page units)*/ 169 } __packed; 170 171 /* 172 * region descriptors, used to load gdt/idt tables before segments yet exist. 173 */ 174 struct region_descriptor { 175 uint64_t rd_limit:16; /* segment extent */ 176 uint64_t rd_base:64 __packed; /* base address */ 177 } __packed; 178 179 #endif /* LOCORE */ 180 181 /* 182 * Segment Protection Exception code bits 183 */ 184 185 #define SEGEX_EXT 0x01 /* recursive or externally induced */ 186 #define SEGEX_IDT 0x02 /* interrupt descriptor table */ 187 #define SEGEX_TI 0x04 /* local descriptor table */ 188 /* other bits are affected descriptor index */ 189 #define SEGEX_IDX(s) (((s)>>3)&0x1fff) 190 191 /* 192 * Size of the IDT table. 193 */ 194 #define NIDT 256 /* we use them all */ 195 /* 196 * Entries in the Interrupt Descriptor Table (IDT) 197 */ 198 #define IDT_DE 0 /* #DE: Divide Error */ 199 #define IDT_DB 1 /* #DB: Debug */ 200 #define IDT_NMI 2 /* Nonmaskable External Interrupt */ 201 #define IDT_BP 3 /* #BP: Breakpoint */ 202 #define IDT_OF 4 /* #OF: Overflow */ 203 #define IDT_BR 5 /* #BR: Bound Range Exceeded */ 204 #define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 205 #define IDT_NM 7 /* #NM: No Math Coprocessor */ 206 #define IDT_DF 8 /* #DF: Double Fault */ 207 #define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 208 #define IDT_TS 10 /* #TS: Invalid TSS */ 209 #define IDT_NP 11 /* #NP: Segment Not Present */ 210 #define IDT_SS 12 /* #SS: Stack Segment Fault */ 211 #define IDT_GP 13 /* #GP: General Protection Fault */ 212 #define IDT_PF 14 /* #PF: Page Fault */ 213 #define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 214 #define IDT_AC 17 /* #AC: Alignment Check */ 215 #define IDT_MC 18 /* #MC: Machine Check */ 216 #define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 217 #define IDT_IO_INTS NRSVIDT /* Base of IDT entries for I/O interrupts. */ 218 #define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */ 219 220 /* 221 * Entries in the Global Descriptor Table (GDT) 222 */ 223 #define GNULL_SEL 0 /* Null Descriptor */ 224 #define GCODE_SEL 1 /* Kernel Code Descriptor */ 225 #define GDATA_SEL 2 /* Kernel Data Descriptor */ 226 #define GUCODE32_SEL 3 /* User 32 bit code Descriptor */ 227 #define GUDATA_SEL 4 /* User 32/64 bit Data Descriptor */ 228 #define GUCODE_SEL 5 /* User 64 bit Code Descriptor */ 229 #define GPROC0_SEL 6 /* TSS for entering kernel etc */ 230 /* slot 7 is second half of GPROC0_SEL */ 231 #define GUGS32_SEL 8 /* User 32 bit GS Descriptor */ 232 #define NGDT 9 233 234 #ifndef LOCORE 235 236 #ifdef _KERNEL 237 extern struct soft_segment_descriptor gdt_segs[]; 238 extern struct gate_descriptor idt_arr[MAXCPU][NIDT]; 239 extern struct region_descriptor r_idt_arr[]; 240 extern struct region_descriptor r_gdt; 241 extern struct user_segment_descriptor gdt[NGDT * MAXCPU]; 242 243 void lgdt(struct region_descriptor *rdp); 244 void sdtossd(struct user_segment_descriptor *sdp, 245 struct soft_segment_descriptor *ssdp); 246 void ssdtosd(struct soft_segment_descriptor *ssdp, 247 struct user_segment_descriptor *sdp); 248 void ssdtosyssd(struct soft_segment_descriptor *ssdp, 249 struct system_segment_descriptor *sdp); 250 #endif /* _KERNEL */ 251 #endif /* LOCORE */ 252 253 #endif /* !_CPU_SEGMENTS_H_ */ 254