segments.h revision 227290
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 227290 2011-11-07 01:53:25Z rstone $ 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#define USD_GETBASE(sd) (((sd)->sd_lobase) | (sd)->sd_hibase << 24) 78#define USD_SETBASE(sd, b) (sd)->sd_lobase = (b); \ 79 (sd)->sd_hibase = ((b) >> 24); 80#define USD_GETLIMIT(sd) (((sd)->sd_lolimit) | (sd)->sd_hilimit << 16) 81#define USD_SETLIMIT(sd, l) (sd)->sd_lolimit = (l); \ 82 (sd)->sd_hilimit = ((l) >> 16); 83 84/* 85 * System segment descriptors (128 bit wide) 86 */ 87struct 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 */ 106struct 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/* 119 * Generic descriptor 120 */ 121union descriptor { 122 struct user_segment_descriptor sd; 123 struct gate_descriptor gd; 124}; 125 126 /* system segments and gate types */ 127#define SDT_SYSNULL 0 /* system null */ 128#define SDT_SYS286TSS 1 /* system 286 TSS available */ 129#define SDT_SYSLDT 2 /* system 64 bit local descriptor table */ 130#define SDT_SYS286BSY 3 /* system 286 TSS busy */ 131#define SDT_SYS286CGT 4 /* system 286 call gate */ 132#define SDT_SYSTASKGT 5 /* system task gate */ 133#define SDT_SYS286IGT 6 /* system 286 interrupt gate */ 134#define SDT_SYS286TGT 7 /* system 286 trap gate */ 135#define SDT_SYSNULL2 8 /* system null again */ 136#define SDT_SYSTSS 9 /* system available 64 bit TSS */ 137#define SDT_SYSNULL3 10 /* system null again */ 138#define SDT_SYSBSY 11 /* system busy 64 bit TSS */ 139#define SDT_SYSCGT 12 /* system 64 bit call gate */ 140#define SDT_SYSNULL4 13 /* system null again */ 141#define SDT_SYSIGT 14 /* system 64 bit interrupt gate */ 142#define SDT_SYSTGT 15 /* system 64 bit trap gate */ 143 144 /* memory segment types */ 145#define SDT_MEMRO 16 /* memory read only */ 146#define SDT_MEMROA 17 /* memory read only accessed */ 147#define SDT_MEMRW 18 /* memory read write */ 148#define SDT_MEMRWA 19 /* memory read write accessed */ 149#define SDT_MEMROD 20 /* memory read only expand dwn limit */ 150#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 151#define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 152#define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 153#define SDT_MEME 24 /* memory execute only */ 154#define SDT_MEMEA 25 /* memory execute only accessed */ 155#define SDT_MEMER 26 /* memory execute read */ 156#define SDT_MEMERA 27 /* memory execute read accessed */ 157#define SDT_MEMEC 28 /* memory execute only conforming */ 158#define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 159#define SDT_MEMERC 30 /* memory execute read conforming */ 160#define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 161 162/* 163 * Software definitions are in this convenient format, 164 * which are translated into inconvenient segment descriptors 165 * when needed to be used by the 386 hardware 166 */ 167 168struct soft_segment_descriptor { 169 unsigned long ssd_base; /* segment base address */ 170 unsigned long ssd_limit; /* segment extent */ 171 unsigned long ssd_type:5; /* segment type */ 172 unsigned long ssd_dpl:2; /* segment descriptor priority level */ 173 unsigned long ssd_p:1; /* segment descriptor present */ 174 unsigned long ssd_long:1; /* long mode (for %cs) */ 175 unsigned long ssd_def32:1; /* default 32 vs 16 bit size */ 176 unsigned long ssd_gran:1; /* limit granularity (byte/page units)*/ 177} __packed; 178 179/* 180 * region descriptors, used to load gdt/idt tables before segments yet exist. 181 */ 182struct region_descriptor { 183 unsigned long rd_limit:16; /* segment extent */ 184 unsigned long rd_base:64 __packed; /* base address */ 185} __packed; 186 187/* 188 * Size of IDT table 189 */ 190#define NIDT 256 /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */ 191#define NRSVIDT 32 /* reserved entries for cpu exceptions */ 192 193/* 194 * Entries in the Interrupt Descriptor Table (IDT) 195 */ 196#define IDT_DE 0 /* #DE: Divide Error */ 197#define IDT_DB 1 /* #DB: Debug */ 198#define IDT_NMI 2 /* Nonmaskable External Interrupt */ 199#define IDT_BP 3 /* #BP: Breakpoint */ 200#define IDT_OF 4 /* #OF: Overflow */ 201#define IDT_BR 5 /* #BR: Bound Range Exceeded */ 202#define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 203#define IDT_NM 7 /* #NM: No Math Coprocessor */ 204#define IDT_DF 8 /* #DF: Double Fault */ 205#define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 206#define IDT_TS 10 /* #TS: Invalid TSS */ 207#define IDT_NP 11 /* #NP: Segment Not Present */ 208#define IDT_SS 12 /* #SS: Stack Segment Fault */ 209#define IDT_GP 13 /* #GP: General Protection Fault */ 210#define IDT_PF 14 /* #PF: Page Fault */ 211#define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 212#define IDT_AC 17 /* #AC: Alignment Check */ 213#define IDT_MC 18 /* #MC: Machine Check */ 214#define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 215#define IDT_IO_INTS NRSVIDT /* Base of IDT entries for I/O interrupts. */ 216#define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */ 217#define IDT_DTRACE_RET 0x20 /* DTrace pid provider Interrupt Vector */ 218 219/* 220 * Entries in the Global Descriptor Table (GDT) 221 */ 222#define GNULL_SEL 0 /* Null Descriptor */ 223#define GNULL2_SEL 1 /* Null Descriptor */ 224#define GUFS32_SEL 2 /* User 32 bit %fs Descriptor */ 225#define GUGS32_SEL 3 /* User 32 bit %gs Descriptor */ 226#define GCODE_SEL 4 /* Kernel Code Descriptor */ 227#define GDATA_SEL 5 /* Kernel Data Descriptor */ 228#define GUCODE32_SEL 6 /* User 32 bit code Descriptor */ 229#define GUDATA_SEL 7 /* User 32/64 bit Data Descriptor */ 230#define GUCODE_SEL 8 /* User 64 bit Code Descriptor */ 231#define GPROC0_SEL 9 /* TSS for entering kernel etc */ 232/* slot 10 is second half of GPROC0_SEL */ 233#define GUSERLDT_SEL 11 /* LDT */ 234/* slot 11 is second half of GUSERLDT_SEL */ 235#define NGDT 13 236 237#ifdef _KERNEL 238extern struct user_segment_descriptor gdt[]; 239extern struct soft_segment_descriptor gdt_segs[]; 240extern struct gate_descriptor *idt; 241extern struct region_descriptor r_gdt, r_idt; 242 243void lgdt(struct region_descriptor *rdp); 244void sdtossd(struct user_segment_descriptor *sdp, 245 struct soft_segment_descriptor *ssdp); 246void ssdtosd(struct soft_segment_descriptor *ssdp, 247 struct user_segment_descriptor *sdp); 248void ssdtosyssd(struct soft_segment_descriptor *ssdp, 249 struct system_segment_descriptor *sdp); 250void update_gdt_gsbase(struct thread *td, uint32_t base); 251void update_gdt_fsbase(struct thread *td, uint32_t base); 252 253#endif /* _KERNEL */ 254 255#endif /* !_MACHINE_SEGMENTS_H_ */ 256