segments.h revision 1.5
1/* $OpenBSD: segments.h,v 1.5 2008/05/23 15:39:43 jasper Exp $ */ 2/* $NetBSD: segments.h,v 1.1 2003/04/26 18:39:47 fvdl Exp $ */ 3 4/*- 5 * Copyright (c) 1995, 1997 6 * Charles M. Hannum. All rights reserved. 7 * Copyright (c) 1989, 1990 William F. Jolitz 8 * Copyright (c) 1990 The Regents of the University of California. 9 * All rights reserved. 10 * 11 * This code is derived from software contributed to Berkeley by 12 * William Jolitz. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)segments.h 7.1 (Berkeley) 5/9/91 39 */ 40 41/* 42 * Adapted for NetBSD/amd64 by fvdl@wasabisystems.com. 43 */ 44 45/* 46 * 386 Segmentation Data Structures and definitions 47 * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989 48 */ 49 50#ifndef _AMD64_SEGMENTS_H_ 51#define _AMD64_SEGMENTS_H_ 52 53/* 54 * Selectors 55 */ 56 57#define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */ 58#define SEL_KPL 0 /* kernel privilege level */ 59#define SEL_UPL 3 /* user privilege level */ 60#define SEL_RPL 3 /* requester's privilege level mask */ 61#define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */ 62#define SEL_LDT 4 /* local descriptor table */ 63 64/* Dynamically allocated TSSs and LDTs start (byte offset) */ 65#define SYSSEL_START (NGDT_MEM << 3) 66#define DYNSEL_START (SYSSEL_START + (NGDT_SYS << 4)) 67 68/* 69 * These define the index not from the start of the GDT, but from 70 * the part of the GDT that they're allocated from. 71 * First NGDT_MEM entries are 8-byte descriptors for CS and DS. 72 * Next NGDT_SYS entries are 16-byte descriptors defining LDTs. 73 * 74 * The rest is 16-byte descriptors for TSS and LDT. 75 */ 76 77#define IDXSEL(s) (((s) >> 3) & 0x1fff) 78#define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 4) 79 80#define GSEL(s,r) (((s) << 3) | r) 81#define GSYSSEL(s,r) ((((s) << 4) + SYSSEL_START) | r) 82#define GDYNSEL(s,r) ((((s) << 4) + DYNSEL_START) | r | SEL_KPL) 83 84#define LSEL(s,r) ((s) | r | SEL_LDT) 85 86#define USERMODE(c, f) (ISPL(c) == SEL_UPL) 87#define KERNELMODE(c, f) (ISPL(c) == SEL_KPL) 88 89#ifndef _LOCORE 90 91/* 92 * Memory and System segment descriptors 93 */ 94 95/* 96 * Below is used for TSS and LDT. 97 */ 98struct sys_segment_descriptor { 99/*BITFIELDTYPE*/ u_int64_t sd_lolimit:16;/* segment extent (lsb) */ 100/*BITFIELDTYPE*/ u_int64_t sd_lobase:24;/* segment base address (lsb) */ 101/*BITFIELDTYPE*/ u_int64_t sd_type:5; /* segment type */ 102/*BITFIELDTYPE*/ u_int64_t sd_dpl:2; /* segment descriptor priority level */ 103/*BITFIELDTYPE*/ u_int64_t sd_p:1; /* segment descriptor present */ 104/*BITFIELDTYPE*/ u_int64_t sd_hilimit:4;/* segment extent (msb) */ 105/*BITFIELDTYPE*/ u_int64_t sd_xx1:3; /* avl, long and def32 (not used) */ 106/*BITFIELDTYPE*/ u_int64_t sd_gran:1; /* limit granularity (byte/page) */ 107/*BITFIELDTYPE*/ u_int64_t sd_hibase:40;/* segment base address (msb) */ 108/*BITFIELDTYPE*/ u_int64_t sd_xx2:8; /* reserved */ 109/*BITFIELDTYPE*/ u_int64_t sd_zero:5; /* must be zero */ 110/*BITFIELDTYPE*/ u_int64_t sd_xx3:19; /* reserved */ 111} __attribute__((packed)); 112 113/* 114 * Below is used for cs, ds, etc. 115 */ 116struct mem_segment_descriptor { 117 unsigned int sd_lolimit:16; /* segment extent (lsb) */ 118 unsigned int sd_lobase:24; /* segment base address (lsb) */ 119 unsigned int sd_type:5; /* segment type */ 120 unsigned int sd_dpl:2; /* segment descriptor priority level */ 121 unsigned int sd_p:1; /* segment descriptor present */ 122 unsigned int sd_hilimit:4; /* segment extent (msb) */ 123 unsigned int sd_avl:1; /* available */ 124 unsigned int sd_long:1; /* long mode */ 125 unsigned int sd_def32:1; /* default 32 vs 16 bit size */ 126 unsigned int sd_gran:1; /* limit granularity (byte/page) */ 127 unsigned int sd_hibase:8; /* segment base address (msb) */ 128} __attribute__((packed)); 129 130/* 131 * Gate descriptors (e.g. indirect descriptors) 132 */ 133struct gate_descriptor { 134/*BITFIELDTYPE*/ u_int64_t gd_looffset:16;/* gate offset (lsb) */ 135/*BITFIELDTYPE*/ u_int64_t gd_selector:16;/* gate segment selector */ 136/*BITFIELDTYPE*/ u_int64_t gd_ist:3; /* IST select */ 137/*BITFIELDTYPE*/ u_int64_t gd_xx1:5; /* reserved */ 138/*BITFIELDTYPE*/ u_int64_t gd_type:5; /* segment type */ 139/*BITFIELDTYPE*/ u_int64_t gd_dpl:2; /* segment descriptor priority level */ 140/*BITFIELDTYPE*/ u_int64_t gd_p:1; /* segment descriptor present */ 141/*BITFIELDTYPE*/ u_int64_t gd_hioffset:48;/* gate offset (msb) */ 142/*BITFIELDTYPE*/ u_int64_t gd_xx2:8; /* reserved */ 143/*BITFIELDTYPE*/ u_int64_t gd_zero:5; /* must be zero */ 144/*BITFIELDTYPE*/ u_int64_t gd_xx3:19; /* reserved */ 145} __attribute__((packed)); 146 147/* 148 * region descriptors, used to load gdt/idt tables before segments yet exist. 149 */ 150struct region_descriptor { 151 u_int16_t rd_limit; /* segment extent */ 152 u_int64_t rd_base; /* base address */ 153} __attribute__((packed)); 154 155#ifdef _KERNEL 156#if 0 157extern struct sys_segment_descriptor *ldt; 158#endif 159extern struct gate_descriptor *idt; 160extern char *gdtstore; 161extern char *ldtstore; 162 163void setgate(struct gate_descriptor *, void *, int, int, int, int); 164void unsetgate(struct gate_descriptor *); 165void setregion(struct region_descriptor *, void *, u_int16_t); 166void set_sys_segment(struct sys_segment_descriptor *, void *, size_t, 167 int, int, int); 168void set_mem_segment(struct mem_segment_descriptor *, void *, size_t, 169 int, int, int, int, int); 170int idt_vec_alloc(int, int); 171void idt_vec_set(int, void (*)(void)); 172void idt_vec_free(int); 173void cpu_init_idt(void); 174 175#endif /* _KERNEL */ 176 177#endif /* !_LOCORE */ 178 179/* system segments and gate types */ 180#define SDT_SYSNULL 0 /* system null */ 181#define SDT_SYS286TSS 1 /* system 286 TSS available */ 182#define SDT_SYSLDT 2 /* system local descriptor table */ 183#define SDT_SYS286BSY 3 /* system 286 TSS busy */ 184#define SDT_SYS286CGT 4 /* system 286 call gate */ 185#define SDT_SYSTASKGT 5 /* system task gate */ 186#define SDT_SYS286IGT 6 /* system 286 interrupt gate */ 187#define SDT_SYS286TGT 7 /* system 286 trap gate */ 188#define SDT_SYSNULL2 8 /* system null again */ 189#define SDT_SYS386TSS 9 /* system 386 TSS available */ 190#define SDT_SYSNULL3 10 /* system null again */ 191#define SDT_SYS386BSY 11 /* system 386 TSS busy */ 192#define SDT_SYS386CGT 12 /* system 386 call gate */ 193#define SDT_SYSNULL4 13 /* system null again */ 194#define SDT_SYS386IGT 14 /* system 386 interrupt gate */ 195#define SDT_SYS386TGT 15 /* system 386 trap gate */ 196 197/* memory segment types */ 198#define SDT_MEMRO 16 /* memory read only */ 199#define SDT_MEMROA 17 /* memory read only accessed */ 200#define SDT_MEMRW 18 /* memory read write */ 201#define SDT_MEMRWA 19 /* memory read write accessed */ 202#define SDT_MEMROD 20 /* memory read only expand dwn limit */ 203#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 204#define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 205#define SDT_MEMRWDA 23 /* memory read write expand dwn limit acessed */ 206#define SDT_MEME 24 /* memory execute only */ 207#define SDT_MEMEA 25 /* memory execute only accessed */ 208#define SDT_MEMER 26 /* memory execute read */ 209#define SDT_MEMERA 27 /* memory execute read accessed */ 210#define SDT_MEMEC 28 /* memory execute only conforming */ 211#define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 212#define SDT_MEMERC 30 /* memory execute read conforming */ 213#define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 214 215/* is memory segment descriptor pointer ? */ 216#define ISMEMSDP(s) ((s->d_type) >= SDT_MEMRO && \ 217 (s->d_type) <= SDT_MEMERAC) 218 219/* is 286 gate descriptor pointer ? */ 220#define IS286GDP(s) ((s->d_type) >= SDT_SYS286CGT && \ 221 (s->d_type) < SDT_SYS286TGT) 222 223/* is 386 gate descriptor pointer ? */ 224#define IS386GDP(s) ((s->d_type) >= SDT_SYS386CGT && \ 225 (s->d_type) < SDT_SYS386TGT) 226 227/* is gate descriptor pointer ? */ 228#define ISGDP(s) (IS286GDP(s) || IS386GDP(s)) 229 230/* is segment descriptor pointer ? */ 231#define ISSDP(s) (ISMEMSDP(s) || !ISGDP(s)) 232 233/* is system segment descriptor pointer ? */ 234#define ISSYSSDP(s) (!ISMEMSDP(s) && !ISGDP(s)) 235 236/* 237 * Segment Protection Exception code bits 238 */ 239#define SEGEX_EXT 0x01 /* recursive or externally induced */ 240#define SEGEX_IDT 0x02 /* interrupt descriptor table */ 241#define SEGEX_TI 0x04 /* local descriptor table */ 242 243/* 244 * Entries in the Interrupt Descriptor Table (IDT) 245 */ 246#define NIDT 256 247#define NRSVIDT 32 /* reserved entries for cpu exceptions */ 248 249/* 250 * Entries in the Global Descriptor Table (GDT) 251 * The code and data descriptors must come first. There 252 * are NGDT_MEM of them. 253 * 254 * Then come the predefined LDT (and possibly TSS) descriptors. 255 * There are NGDT_SYS of them. 256 */ 257#define GNULL_SEL 0 /* Null descriptor */ 258#define GCODE_SEL 1 /* Kernel code descriptor */ 259#define GDATA_SEL 2 /* Kernel data descriptor */ 260#define GUCODE_SEL 3 /* User code descriptor */ 261#define GUDATA_SEL 4 /* User data descriptor */ 262#define GAPM32CODE_SEL 5 263#define GAPM16CODE_SEL 6 264#define GAPMDATA_SEL 7 265#define GBIOSCODE_SEL 8 266#define GBIOSDATA_SEL 9 267#define GPNPBIOSCODE_SEL 10 268#define GPNPBIOSDATA_SEL 11 269#define GPNPBIOSSCRATCH_SEL 12 270#define GPNPBIOSTRAMP_SEL 13 271#define GUCODE32_SEL 14 272#define GUDATA32_SEL 15 273#define NGDT_MEM 16 274 275#define GLDT_SEL 0 /* Default LDT descriptor */ 276#define NGDT_SYS 1 277 278#define GDT_SYS_OFFSET (NGDT_MEM << 3) 279 280#define GDT_ADDR_MEM(s,i) \ 281 ((struct mem_segment_descriptor *)((s) + ((i) << 3))) 282#define GDT_ADDR_SYS(s,i) \ 283 ((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START))) 284 285/* 286 * Byte offsets in the Local Descriptor Table (LDT) 287 * Strange order because of syscall/sysret insns 288 */ 289#define LSYS5CALLS_SEL 0 /* iBCS system call gate */ 290#define LUCODE32_SEL 8 /* 32 bit user code descriptor */ 291#define LUDATA_SEL 16 /* User data descriptor */ 292#define LUCODE_SEL 24 /* User code descriptor */ 293#define LSOL26CALLS_SEL 32 /* Solaris 2.6 system call gate */ 294#define LUDATA32_SEL 56 /* 32 bit user data descriptor (needed?)*/ 295#define LBSDICALLS_SEL 128 /* BSDI system call gate */ 296 297#define LDT_SIZE 144 298 299#define LSYSRETBASE_SEL LUCODE32_SEL 300 301/* 302 * Checks for valid user selectors. 303 */ 304#define VALID_USER_DSEL32(s) \ 305 ((s) == GSEL(GUDATA32_SEL, SEL_UPL) || (s) == LSEL(LUDATA32_SEL, SEL_UPL)) 306#define VALID_USER_CSEL32(s) \ 307 ((s) == GSEL(GUCODE32_SEL, SEL_UPL) || (s) == LSEL(LUCODE32_SEL, SEL_UPL)) 308 309#define VALID_USER_CSEL(s) \ 310 ((s) == GSEL(GUCODE_SEL, SEL_UPL) || (s) == LSEL(LUCODE_SEL, SEL_UPL)) 311#define VALID_USER_DSEL(s) \ 312 ((s) == GSEL(GUDATA_SEL, SEL_UPL) || (s) == LSEL(LUDATA_SEL, SEL_UPL)) 313 314#endif /* _AMD64_SEGMENTS_H_ */ 315