segments.h revision 1.28
1 /* $NetBSD: segments.h,v 1.28 2016/09/02 08:52:12 maxv Exp $ */ 2 3 /*- 4 * Copyright (c) 1990 The Regents of the University of California. 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 * @(#)segments.h 7.1 (Berkeley) 5/9/91 35 */ 36 37 /*- 38 * Copyright (c) 1995, 1997 39 * Charles M. Hannum. All rights reserved. 40 * Copyright (c) 1989, 1990 William F. Jolitz 41 * 42 * This code is derived from software contributed to Berkeley by 43 * William Jolitz. 44 * 45 * Redistribution and use in source and binary forms, with or without 46 * modification, are permitted provided that the following conditions 47 * are met: 48 * 1. Redistributions of source code must retain the above copyright 49 * notice, this list of conditions and the following disclaimer. 50 * 2. Redistributions in binary form must reproduce the above copyright 51 * notice, this list of conditions and the following disclaimer in the 52 * documentation and/or other materials provided with the distribution. 53 * 3. All advertising materials mentioning features or use of this software 54 * must display the following acknowledgement: 55 * This product includes software developed by the University of 56 * California, Berkeley and its contributors. 57 * 4. Neither the name of the University nor the names of its contributors 58 * may be used to endorse or promote products derived from this software 59 * without specific prior written permission. 60 * 61 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 62 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 63 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 64 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 65 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 66 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 67 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 68 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 69 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 70 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 71 * SUCH DAMAGE. 72 * 73 * @(#)segments.h 7.1 (Berkeley) 5/9/91 74 */ 75 76 /* 77 * Adapted for NetBSD/amd64 by fvdl (at) wasabisystems.com. 78 */ 79 80 /* 81 * 386 Segmentation Data Structures and definitions 82 * William F. Jolitz (william (at) ernie.berkeley.edu) 6/20/1989 83 */ 84 85 #ifndef _AMD64_SEGMENTS_H_ 86 #define _AMD64_SEGMENTS_H_ 87 88 #ifdef __x86_64__ 89 90 #ifdef _KERNEL_OPT 91 #include "opt_xen.h" 92 #endif 93 94 /* 95 * Selectors 96 */ 97 98 #define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */ 99 #ifdef XEN 100 #define SEL_KPL 3 /* kernel privilege level */ 101 #define SEL_XPL 0 /* Xen Hypervisor privilege level */ 102 #else 103 #define SEL_KPL 0 /* kernel privilege level */ 104 #endif 105 #define SEL_UPL 3 /* user privilege level */ 106 #define SEL_RPL 3 /* requester's privilege level mask */ 107 #define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */ 108 #define SEL_LDT 4 /* local descriptor table */ 109 110 /* Dynamically allocated TSSs and LDTs start (byte offset) */ 111 #define SYSSEL_START (NGDT_MEM << 3) 112 #define DYNSEL_START (SYSSEL_START + (NGDT_SYS << 4)) 113 114 /* 115 * These define the index not from the start of the GDT, but from 116 * the part of the GDT that they're allocated from. 117 * First NGDT_MEM entries are 8-byte descriptors for CS and DS. 118 * Next NGDT_SYS entries are 16-byte descriptors defining LDTs. 119 * 120 * The rest is 16-byte descriptors for TSS and LDT. 121 */ 122 123 #define IDXSEL(s) (((s) >> 3) & 0x1fff) 124 #define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 4) 125 126 #define GSEL(s,r) (((s) << 3) | r) 127 #define GSYSSEL(s,r) ((((s) << 4) + SYSSEL_START) | r) 128 #define GDYNSEL(s,r) ((((s) << 4) + DYNSEL_START) | r | SEL_KPL) 129 130 #define LSEL(s,r) ((s) | r | SEL_LDT) 131 132 #define USERMODE(c, f) (ISPL(c) == SEL_UPL) 133 #ifdef XEN 134 /* 135 * As KPL == UPL, Xen emulate interrupt in kernel context by pushing 136 * a fake CS with XPL privilege 137 */ 138 #define KERNELMODE(c, f) (ISPL(c) == SEL_XPL) 139 #else 140 #define KERNELMODE(c, f) (ISPL(c) == SEL_KPL) 141 #endif 142 143 #ifndef _LOCORE 144 145 /* 146 * Memory and System segment descriptors 147 */ 148 149 /* 150 * System segment descriptor (16 bytes): used for TSS and LDT. 151 */ 152 struct sys_segment_descriptor { 153 uint64_t sd_lolimit:16; /* segment extent (lsb) */ 154 uint64_t sd_lobase:24; /* segment base address (lsb) */ 155 uint64_t sd_type:5; /* segment type */ 156 uint64_t sd_dpl:2; /* segment descriptor priority level */ 157 uint64_t sd_p:1; /* segment descriptor present */ 158 uint64_t sd_hilimit:4; /* segment extent (msb) */ 159 uint64_t sd_xx1:3; /* avl, long and def32 (not used) */ 160 uint64_t sd_gran:1; /* limit granularity (byte/page) */ 161 uint64_t sd_hibase:40; /* segment base address (msb) */ 162 uint64_t sd_xx2:8; /* reserved */ 163 uint64_t sd_zero:5; /* must be zero */ 164 uint64_t sd_xx3:19; /* reserved */ 165 } __packed; 166 167 /* 168 * Memory segment descriptor (8 bytes): used for cs, ds, etc. 169 */ 170 struct mem_segment_descriptor { 171 unsigned sd_lolimit:16; /* segment extent (lsb) */ 172 unsigned sd_lobase:24; /* segment base address (lsb) */ 173 unsigned sd_type:5; /* segment type */ 174 unsigned sd_dpl:2; /* segment descriptor priority level */ 175 unsigned sd_p:1; /* segment descriptor present */ 176 unsigned sd_hilimit:4; /* segment extent (msb) */ 177 unsigned sd_avl:1; /* available */ 178 unsigned sd_long:1; /* long mode */ 179 unsigned sd_def32:1; /* default 32 vs 16 bit size */ 180 unsigned sd_gran:1; /* limit granularity (byte/page) */ 181 unsigned sd_hibase:8; /* segment base address (msb) */ 182 } __packed; 183 184 /* 185 * Common part of the above structures. Used to walk descriptor tables. 186 */ 187 struct common_segment_descriptor { 188 unsigned sdc_lolimit:16; 189 unsigned sdc_lobase:24; 190 unsigned sdc_type:5; 191 unsigned sdc_other:19; 192 } __packed; 193 194 /* 195 * Gate descriptors (16 bytes). 196 */ 197 struct gate_descriptor { 198 uint64_t gd_looffset:16;/* gate offset (lsb) */ 199 uint64_t gd_selector:16;/* gate segment selector */ 200 uint64_t gd_ist:3; /* IST select */ 201 uint64_t gd_xx1:5; /* reserved */ 202 uint64_t gd_type:5; /* segment type */ 203 uint64_t gd_dpl:2; /* segment descriptor priority level */ 204 uint64_t gd_p:1; /* segment descriptor present */ 205 uint64_t gd_hioffset:48;/* gate offset (msb) */ 206 uint64_t gd_xx2:8; /* reserved */ 207 uint64_t gd_zero:5; /* must be zero */ 208 uint64_t gd_xx3:19; /* reserved */ 209 } __packed; 210 211 /* 212 * Generic descriptor (8 bytes). Note: it does not include system segment 213 * descriptors and gate descriptors, since these are 16-byte-long. 214 */ 215 union descriptor { 216 struct mem_segment_descriptor sd; 217 uint32_t raw[2]; 218 uint64_t raw64; 219 } __packed; 220 221 /* 222 * Region descriptors, used to load gdt/idt tables before segments yet exist. 223 */ 224 struct region_descriptor { 225 uint16_t rd_limit; /* segment extent */ 226 uint64_t rd_base; /* base address */ 227 } __packed; 228 229 #ifdef _KERNEL 230 #ifdef XEN 231 extern struct trap_info *idt; 232 #else 233 extern struct gate_descriptor *idt; 234 #endif 235 extern char *gdtstore; 236 extern char *ldtstore; 237 238 void setgate(struct gate_descriptor *, void *, int, int, int, int); 239 void unsetgate(struct gate_descriptor *); 240 void setregion(struct region_descriptor *, void *, uint16_t); 241 void set_sys_segment(struct sys_segment_descriptor *, void *, size_t, 242 int, int, int); 243 void set_mem_segment(struct mem_segment_descriptor *, void *, size_t, 244 int, int, int, int, int); 245 void cpu_init_idt(void); 246 void update_descriptor(void *, void *); 247 248 #if !defined(XEN) 249 void idt_vec_reserve(int); 250 int idt_vec_alloc(int, int); 251 void idt_vec_set(int, void (*)(void)); 252 void idt_vec_free(int); 253 #endif 254 255 struct lwp; 256 void cpu_fsgs_zero(struct lwp *); 257 void cpu_fsgs_reload(struct lwp *, int, int); 258 259 #endif /* _KERNEL */ 260 261 #endif /* !_LOCORE */ 262 263 /* system segments and gate types */ 264 #define SDT_SYSNULL 0 /* system null */ 265 #define SDT_SYS286TSS 1 /* system 286 TSS available */ 266 #define SDT_SYSLDT 2 /* system local descriptor table */ 267 #define SDT_SYS286BSY 3 /* system 286 TSS busy */ 268 #define SDT_SYS286CGT 4 /* system 286 call gate */ 269 #define SDT_SYSTASKGT 5 /* system task gate */ 270 #define SDT_SYS286IGT 6 /* system 286 interrupt gate */ 271 #define SDT_SYS286TGT 7 /* system 286 trap gate */ 272 #define SDT_SYSNULL2 8 /* system null again */ 273 #define SDT_SYS386TSS 9 /* system 386 TSS available */ 274 #define SDT_SYSNULL3 10 /* system null again */ 275 #define SDT_SYS386BSY 11 /* system 386 TSS busy */ 276 #define SDT_SYS386CGT 12 /* system 386 call gate */ 277 #define SDT_SYSNULL4 13 /* system null again */ 278 #define SDT_SYS386IGT 14 /* system 386 interrupt gate */ 279 #define SDT_SYS386TGT 15 /* system 386 trap gate */ 280 281 /* memory segment types */ 282 #define SDT_MEMRO 16 /* memory read only */ 283 #define SDT_MEMROA 17 /* memory read only accessed */ 284 #define SDT_MEMRW 18 /* memory read write */ 285 #define SDT_MEMRWA 19 /* memory read write accessed */ 286 #define SDT_MEMROD 20 /* memory read only expand dwn limit */ 287 #define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ 288 #define SDT_MEMRWD 22 /* memory read write expand dwn limit */ 289 #define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ 290 #define SDT_MEME 24 /* memory execute only */ 291 #define SDT_MEMEA 25 /* memory execute only accessed */ 292 #define SDT_MEMER 26 /* memory execute read */ 293 #define SDT_MEMERA 27 /* memory execute read accessed */ 294 #define SDT_MEMEC 28 /* memory execute only conforming */ 295 #define SDT_MEMEAC 29 /* memory execute only accessed conforming */ 296 #define SDT_MEMERC 30 /* memory execute read conforming */ 297 #define SDT_MEMERAC 31 /* memory execute read accessed conforming */ 298 299 /* is memory segment descriptor pointer ? */ 300 #define ISMEMSDP(s) ((s->d_type) >= SDT_MEMRO && \ 301 (s->d_type) <= SDT_MEMERAC) 302 303 /* is 286 gate descriptor pointer ? */ 304 #define IS286GDP(s) ((s->d_type) >= SDT_SYS286CGT && \ 305 (s->d_type) < SDT_SYS286TGT) 306 307 /* is 386 gate descriptor pointer ? */ 308 #define IS386GDP(s) ((s->d_type) >= SDT_SYS386CGT && \ 309 (s->d_type) < SDT_SYS386TGT) 310 311 /* is gate descriptor pointer ? */ 312 #define ISGDP(s) (IS286GDP(s) || IS386GDP(s)) 313 314 /* is segment descriptor pointer ? */ 315 #define ISSDP(s) (ISMEMSDP(s) || !ISGDP(s)) 316 317 /* is system segment descriptor pointer ? */ 318 #define ISSYSSDP(s) (!ISMEMSDP(s) && !ISGDP(s)) 319 320 /* 321 * Segment Protection Exception code bits 322 */ 323 #define SEGEX_EXT 0x01 /* recursive or externally induced */ 324 #define SEGEX_IDT 0x02 /* interrupt descriptor table */ 325 #define SEGEX_TI 0x04 /* local descriptor table */ 326 327 /* 328 * Entries in the Interrupt Descriptor Table (IDT) 329 */ 330 #define NIDT 256 331 #define NCPUIDT 32 /* reserved entries for CPU exceptions */ 332 333 /* 334 * Entries in the Global Descriptor Table (GDT) 335 * The code and data descriptors must come first. There 336 * are NGDT_MEM of them. 337 * 338 * Then come the predefined LDT (and possibly TSS) descriptors. 339 * There are NGDT_SYS of them. 340 */ 341 #define GNULL_SEL 0 /* Null descriptor */ 342 #define GCODE_SEL 1 /* Kernel code descriptor */ 343 #define GDATA_SEL 2 /* Kernel data descriptor */ 344 #define GUCODE_SEL 3 /* User code descriptor */ 345 #define GUDATA_SEL 4 /* User data descriptor */ 346 #define GAPM32CODE_SEL 5 347 #define GAPM16CODE_SEL 6 348 #define GAPMDATA_SEL 7 349 #define GBIOSCODE_SEL 8 350 #define GBIOSDATA_SEL 9 351 #define GPNPBIOSCODE_SEL 10 352 #define GPNPBIOSDATA_SEL 11 353 #define GPNPBIOSSCRATCH_SEL 12 354 #define GPNPBIOSTRAMP_SEL 13 355 #define GUCODE32_SEL 14 356 #define GUDATA32_SEL 15 357 #define GUFS_SEL 16 /* 32-bit Per-thread %fs */ 358 #define GUGS_SEL 17 /* 32-bit Per-thread %gs */ 359 #define NGDT_MEM 18 360 361 #define GLDT_SEL 0 /* Default LDT descriptor */ 362 #define NGDT_SYS 1 363 364 #define GDT_ADDR_MEM(s,i) \ 365 ((struct mem_segment_descriptor *)((s) + ((i) << 3))) 366 #define GDT_ADDR_SYS(s,i) \ 367 ((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START))) 368 369 /* 370 * Byte offsets in the Local Descriptor Table (LDT) 371 * Strange order because of syscall/sysret insns 372 */ 373 #define LSYS5CALLS_SEL 0 /* iBCS system call gate */ 374 /* 8 second half */ 375 #define LSOL26CALLS_SEL 32 /* Solaris 2.6 system call gate */ 376 /* 40 second half */ 377 #define LUCODE32_SEL 48 /* 32 bit user code descriptor */ 378 #define LUDATA_SEL 56 /* User data descriptor */ 379 #define LUCODE_SEL 64 /* User code descriptor */ 380 #define LUDATA32_SEL 72 /* 32 bit user data descriptor (needed?)*/ 381 #define LBSDICALLS_SEL 128 /* BSDI system call gate */ 382 /* 136 second half */ 383 384 #define LDT_SIZE 144 385 386 #define LSYSRETBASE_SEL LUCODE32_SEL 387 388 /* 389 * Checks for valid user selectors. If USER_LDT ever gets implemented 390 * for amd64, these must check the ldt length and SEL_UPL if a user 391 * ldt is active. 392 */ 393 #define VALID_USER_DSEL32(s) \ 394 (((s) & 0xffff) == GSEL(GUDATA32_SEL, SEL_UPL) || \ 395 ((s) & 0xffff) == LSEL(LUDATA32_SEL, SEL_UPL)) 396 #define VALID_USER_CSEL32(s) \ 397 ((s) == GSEL(GUCODE32_SEL, SEL_UPL) || (s) == LSEL(LUCODE32_SEL, SEL_UPL)) 398 #define VALID_USER_FSEL32(s) \ 399 (((s) & 0xffff) == GSEL(GUFS_SEL, SEL_UPL)) 400 #define VALID_USER_GSEL32(s) \ 401 (((s) & 0xffff) == GSEL(GUGS_SEL, SEL_UPL)) 402 403 #define VALID_USER_CSEL(s) \ 404 ((s) == GSEL(GUCODE_SEL, SEL_UPL) || (s) == LSEL(LUCODE_SEL, SEL_UPL)) 405 #define VALID_USER_DSEL(s) \ 406 ((s) == GSEL(GUDATA_SEL, SEL_UPL) || (s) == LSEL(LUDATA_SEL, SEL_UPL)) 407 408 #else /* __x86_64__ */ 409 410 #include <i386/segments.h> 411 412 #endif /* __x86_64__ */ 413 414 #endif /* _AMD64_SEGMENTS_H_ */ 415
Indexes created Sun Sep 28 16:09:52 GMT 2025