segments.h revision 190620
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 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * from: @(#)segments.h 7.1 (Berkeley) 5/9/91 34 * $FreeBSD: head/sys/amd64/include/segments.h 190620 2009-04-01 13:09:26Z kib $ 35 */ 36 37#ifndef _MACHINE_SEGMENTS_H_ 38#define _MACHINE_SEGMENTS_H_ 39 40/* 41 * AMD64 Segmentation Data Structures and definitions 42 */ 43 44/* 45 * Selectors 46 */ 47 48#define SEL_RPL_MASK 3 /* requester priv level */ 49#define ISPL(s) ((s)&3) /* what is the priority level of a selector */ 50#define SEL_KPL 0 /* kernel priority level */ 51#define SEL_UPL 3 /* user priority level */ 52#define ISLDT(s) ((s)&SEL_LDT) /* is it local or global */ 53#define SEL_LDT 4 /* local descriptor table */ 54#define IDXSEL(s) (((s)>>3) & 0x1fff) /* index of selector */ 55#define LSEL(s,r) (((s)<<3) | SEL_LDT | r) /* a local selector */ 56#define GSEL(s,r) (((s)<<3) | r) /* a global selector */ 57 58/* 59 * User segment descriptors (%cs, %ds etc for compatability apps. 64 bit wide) 60 * For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl, 61 * sd_p, sd_l and sd_def32 which must be zero). %ds only has sd_p. 62 */ 63struct user_segment_descriptor { 64 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 65 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 66 u_int64_t sd_type:5; /* segment type */ 67 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 68 u_int64_t sd_p:1; /* segment descriptor present */ 69 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 70 u_int64_t sd_xx:1; /* unused */ 71 u_int64_t sd_long:1; /* long mode (cs only) */ 72 u_int64_t sd_def32:1; /* default 32 vs 16 bit size */ 73 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 74 u_int64_t sd_hibase:8; /* segment base address (msb) */ 75} __packed; 76 77/* 78 * System segment descriptors (128 bit wide) 79 */ 80struct system_segment_descriptor { 81 u_int64_t sd_lolimit:16; /* segment extent (lsb) */ 82 u_int64_t sd_lobase:24; /* segment base address (lsb) */ 83 u_int64_t sd_type:5; /* segment type */ 84 u_int64_t sd_dpl:2; /* segment descriptor priority level */ 85 u_int64_t sd_p:1; /* segment descriptor present */ 86 u_int64_t sd_hilimit:4; /* segment extent (msb) */ 87 u_int64_t sd_xx0:3; /* unused */ 88 u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/ 89 u_int64_t sd_hibase:40 __packed;/* segment base address (msb) */ 90 u_int64_t sd_xx1:8; 91 u_int64_t sd_mbz:5; /* MUST be zero */ 92 u_int64_t sd_xx2:19; 93} __packed; 94 95/* 96 * Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit) 97 * Only interrupt and trap gates have gd_ist. 98 */ 99struct gate_descriptor { 100 u_int64_t gd_looffset:16; /* gate offset (lsb) */ 101 u_int64_t gd_selector:16; /* gate segment selector */ 102 u_int64_t gd_ist:3; /* IST table index */ 103 u_int64_t gd_xx:5; /* unused */ 104 u_int64_t gd_type:5; /* segment type */ 105 u_int64_t gd_dpl:2; /* segment descriptor priority level */ 106 u_int64_t gd_p:1; /* segment descriptor present */ 107 u_int64_t gd_hioffset:48 __packed; /* gate offset (msb) */ 108 u_int64_t sd_xx1:32; 109} __packed; 110 111/* 112 * Generic descriptor 113 */ 114union descriptor { 115 struct user_segment_descriptor sd; 116 struct gate_descriptor gd; 117}; 118 119 /* system segments and gate types */ 120#define SDT_SYSNULL 0 /* system null */ 121#define SDT_SYS286TSS 1 /* system 286 TSS available */ 122#define SDT_SYSLDT 2 /* system 64 bit local descriptor table */ 123#define SDT_SYS286BSY 3 /* system 286 TSS busy */ 124#define SDT_SYS286CGT 4 /* system 286 call gate */ 125#define SDT_SYSTASKGT 5 /* system task gate */ 126#define SDT_SYS286IGT 6 /* system 286 interrupt gate */ 127#define SDT_SYS286TGT 7 /* system 286 trap gate */ 128#define SDT_SYSNULL2 8 /* system null again */ 129#define SDT_SYSTSS 9 /* system available 64 bit TSS */ 130#define SDT_SYSNULL3 10 /* system null again */ 131#define SDT_SYSBSY 11 /* system busy 64 bit TSS */ 132#define SDT_SYSCGT 12 /* system 64 bit call gate */ 133#define SDT_SYSNULL4 13 /* system null again */ 134#define SDT_SYSIGT 14 /* system 64 bit interrupt gate */ 135#define SDT_SYSTGT 15 /* system 64 bit trap gate */ 136 137 /* memory segment types */ 138#define SDT_MEMRO 16 /* memory read only */ 139#define SDT_MEMROA 17 /* memory read only accessed */ 140#define SDT_MEMRW 18 /* memory read write */ 141#define SDT_MEMRWA 19 /* memory read write accessed */ 142#define SDT_MEMROD 20 /* memory read only expand dwn limit */ 143#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 144#define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 145#define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 146#define SDT_MEME 24 /* memory execute only */ 147#define SDT_MEMEA 25 /* memory execute only accessed */ 148#define SDT_MEMER 26 /* memory execute read */ 149#define SDT_MEMERA 27 /* memory execute read accessed */ 150#define SDT_MEMEC 28 /* memory execute only conforming */ 151#define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 152#define SDT_MEMERC 30 /* memory execute read conforming */ 153#define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 154 155/* 156 * Software definitions are in this convenient format, 157 * which are translated into inconvenient segment descriptors 158 * when needed to be used by the 386 hardware 159 */ 160 161struct soft_segment_descriptor { 162 unsigned long ssd_base; /* segment base address */ 163 unsigned long ssd_limit; /* segment extent */ 164 unsigned long ssd_type:5; /* segment type */ 165 unsigned long ssd_dpl:2; /* segment descriptor priority level */ 166 unsigned long ssd_p:1; /* segment descriptor present */ 167 unsigned long ssd_long:1; /* long mode (for %cs) */ 168 unsigned long ssd_def32:1; /* default 32 vs 16 bit size */ 169 unsigned long ssd_gran:1; /* limit granularity (byte/page units)*/ 170} __packed; 171 172/* 173 * region descriptors, used to load gdt/idt tables before segments yet exist. 174 */ 175struct region_descriptor { 176 unsigned long rd_limit:16; /* segment extent */ 177 unsigned long rd_base:64 __packed; /* base address */ 178} __packed; 179 180/* 181 * Size of IDT table 182 */ 183#define NIDT 256 /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */ 184#define NRSVIDT 32 /* reserved entries for cpu exceptions */ 185 186/* 187 * Entries in the Interrupt Descriptor Table (IDT) 188 */ 189#define IDT_DE 0 /* #DE: Divide Error */ 190#define IDT_DB 1 /* #DB: Debug */ 191#define IDT_NMI 2 /* Nonmaskable External Interrupt */ 192#define IDT_BP 3 /* #BP: Breakpoint */ 193#define IDT_OF 4 /* #OF: Overflow */ 194#define IDT_BR 5 /* #BR: Bound Range Exceeded */ 195#define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 196#define IDT_NM 7 /* #NM: No Math Coprocessor */ 197#define IDT_DF 8 /* #DF: Double Fault */ 198#define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 199#define IDT_TS 10 /* #TS: Invalid TSS */ 200#define IDT_NP 11 /* #NP: Segment Not Present */ 201#define IDT_SS 12 /* #SS: Stack Segment Fault */ 202#define IDT_GP 13 /* #GP: General Protection Fault */ 203#define IDT_PF 14 /* #PF: Page Fault */ 204#define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 205#define IDT_AC 17 /* #AC: Alignment Check */ 206#define IDT_MC 18 /* #MC: Machine Check */ 207#define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 208#define IDT_IO_INTS NRSVIDT /* Base of IDT entries for I/O interrupts. */ 209#define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */ 210 211/* 212 * Entries in the Global Descriptor Table (GDT) 213 */ 214#define GNULL_SEL 0 /* Null Descriptor */ 215#define GNULL2_SEL 1 /* Null Descriptor */ 216#define GUFS32_SEL 2 /* User 32 bit %fs Descriptor */ 217#define GUGS32_SEL 3 /* User 32 bit %gs Descriptor */ 218#define GCODE_SEL 4 /* Kernel Code Descriptor */ 219#define GDATA_SEL 5 /* Kernel Data Descriptor */ 220#define GUCODE32_SEL 6 /* User 32 bit code Descriptor */ 221#define GUDATA_SEL 7 /* User 32/64 bit Data Descriptor */ 222#define GUCODE_SEL 8 /* User 64 bit Code Descriptor */ 223#define GPROC0_SEL 9 /* TSS for entering kernel etc */ 224/* slot 10 is second half of GPROC0_SEL */ 225#define GUSERLDT_SEL 11 /* LDT */ 226/* slot 11 is second half of GUSERLDT_SEL */ 227#define NGDT 13 228 229#ifdef _KERNEL 230extern struct user_segment_descriptor gdt[]; 231extern struct soft_segment_descriptor gdt_segs[]; 232extern struct gate_descriptor *idt; 233extern struct region_descriptor r_gdt, r_idt; 234 235void lgdt(struct region_descriptor *rdp); 236void sdtossd(struct user_segment_descriptor *sdp, 237 struct soft_segment_descriptor *ssdp); 238void ssdtosd(struct soft_segment_descriptor *ssdp, 239 struct user_segment_descriptor *sdp); 240void ssdtosyssd(struct soft_segment_descriptor *ssdp, 241 struct system_segment_descriptor *sdp); 242void update_gdt_gsbase(struct thread *td, uint32_t base); 243void update_gdt_fsbase(struct thread *td, uint32_t base); 244 245#endif /* _KERNEL */ 246 247#endif /* !_MACHINE_SEGMENTS_H_ */ 248