1 /* 2 * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. 3 */ 4 /* 5 * Copyright 2011 Joyent, Inc. All rights reserved. 6 */ 7 8 #ifndef _SYS_SEGMENTS_H 9 #define _SYS_SEGMENTS_H 10 11 #ifdef __cplusplus 12 extern "C" { 13 #endif 14 15 /* 16 * Copyright (c) 1989, 1990 William F. Jolitz 17 * Copyright (c) 1990 The Regents of the University of California. 18 * All rights reserved. 19 * 20 * This code is derived from software contributed to Berkeley by 21 * William Jolitz. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the above copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * This product includes software developed by the University of 34 * California, Berkeley and its contributors. 35 * 4. Neither the name of the University nor the names of its contributors 36 * may be used to endorse or promote products derived from this software 37 * without specific prior written permission. 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 40 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 42 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 43 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 44 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 45 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 47 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 48 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 49 * SUCH DAMAGE. 50 * 51 * from: @(#)segments.h 7.1 (Berkeley) 5/9/91 52 * $FreeBSD: src/sys/i386/include/segments.h,v 1.34 2003/09/10 01:07:04 53 * jhb Exp $ 54 * 55 * 386 Segmentation Data Structures and definitions 56 * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989 57 */ 58 59 #include <sys/tss.h> 60 61 /* 62 * Selector register format 63 * CS, DS, ES, FS, GS, SS 64 * 65 * 15 3 2 1 0 66 * +---------------------+---+----+ 67 * | SI |TI |RPL | 68 * +---------------------+---+----+ 69 * 70 * SI = selector index 71 * TI = table indicator (0 = GDT, 1 = LDT) 72 * RPL = requestor privilege level 73 */ 74 #if !defined(_ASM) || defined(__GNUC_AS__) 75 #define IDXTOSEL(s) ((s) << 3) /* index to selector */ 76 #define SEL_GDT(s, r) (IDXTOSEL(s) | r) /* global sel */ 77 #else 78 #define IDXTOSEL(s) [s << 3] 79 #define SEL_GDT(s, r) [IDXTOSEL(s) | r] 80 #endif 81 82 #define SELTOIDX(s) ((s) >> 3) /* selector to index */ 83 84 /* 85 * SEL_(KPL,UPL,XPL) is the RPL or DPL value for code and data selectors 86 * and their descriptors respectively. 87 * 88 * TRP_(KPL,UPL,XPL) is used to indicate the DPL for system gates only. 89 * 90 * This distinction is important to support para-virt guests on the 91 * 64-bit hypervisor. Both guest kernel and user run in ring 3 and the 92 * hypervisor runs in ring 0. When the kernel creates its trap and 93 * interrupt gates it needs a way to prevent any arbitrary int $n 94 * instruction from entering a gate that is not expected. The hypervisor 95 * allows these gates to have a DPL from 1 to 3. By creating gates 96 * with a DPL below user (ring 3) the int $n will generate a #gp fault 97 * which the hypervisor catches and forwards to the guest. 98 */ 99 #if defined(__xpv) 100 101 #if defined(__amd64) 102 103 #define SEL_XPL 0 /* hypervisor privilege level */ 104 #define SEL_KPL 3 /* both kernel and user in ring 3 */ 105 #define TRP_KPL 1 /* system gate priv (user blocked) */ 106 107 #elif defined(__i386) 108 109 #define SEL_XPL 0 /* hypervisor privilege level */ 110 #define SEL_KPL 1 /* kernel privilege level */ 111 #define TRP_KPL SEL_KPL /* system gate priv (user blocked) */ 112 113 #endif /* __i386 */ 114 115 #define TRP_XPL 0 /* system gate priv (hypervisor) */ 116 117 #else /* __xpv */ 118 119 #define SEL_KPL 0 /* kernel privilege level on metal */ 120 #define TRP_KPL SEL_KPL /* system gate priv (user blocked) */ 121 122 #endif /* __xpv */ 123 124 #define SEL_UPL 3 /* user priority level */ 125 #define TRP_UPL 3 /* system gate priv (user allowed) */ 126 #define SEL_TI_LDT 4 /* local descriptor table */ 127 #define SEL_LDT(s) (IDXTOSEL(s) | SEL_TI_LDT | SEL_UPL) /* local sel */ 128 #define CPL_MASK 3 /* RPL mask for selector */ 129 #define SELISLDT(s) (((s) & SEL_TI_LDT) == SEL_TI_LDT) 130 #define SELISUPL(s) (((s) & CPL_MASK) == SEL_UPL) 131 132 #ifndef _ASM 133 134 typedef uint16_t selector_t; /* selector reigster */ 135 136 /* 137 * Hardware descriptor table register format for GDT and IDT. 138 */ 139 #if defined(__amd64) 140 141 #pragma pack(2) 142 typedef struct { 143 uint16_t dtr_limit; /* table limit */ 144 uint64_t dtr_base; /* table base address */ 145 } desctbr_t; 146 #pragma pack() 147 148 #elif defined(__i386) 149 150 #pragma pack(2) 151 typedef struct { 152 uint16_t dtr_limit; /* table limit */ 153 uint32_t dtr_base; /* table base address */ 154 } desctbr_t; 155 #pragma pack() 156 157 #endif /* __i386 */ 158 159 /* 160 * Functions for loading and storing descriptor table 161 * registers. 162 */ 163 extern void rd_idtr(desctbr_t *); 164 extern void wr_idtr(desctbr_t *); 165 extern void rd_gdtr(desctbr_t *); 166 extern void wr_gdtr(desctbr_t *); 167 extern void wr_ldtr(selector_t); 168 extern selector_t rd_ldtr(void); 169 extern void wr_tsr(selector_t); 170 extern void kmdb_enter(void); 171 172 #if defined(__amd64) 173 174 /* 175 * inlines for update_segregs 176 */ 177 extern void __set_ds(selector_t); 178 extern void __set_es(selector_t); 179 extern void __set_fs(selector_t); 180 extern void __set_gs(selector_t); 181 extern void __swapgs(void); 182 #endif /* __amd64 */ 183 184 #if defined(__amd64) 185 extern void load_segment_registers(selector_t, selector_t, selector_t, 186 selector_t); /* (alphabetical) */ 187 #elif defined(__i386) 188 extern void load_segment_registers(selector_t, selector_t, selector_t, 189 selector_t, selector_t, selector_t); /* (alphabetical) */ 190 #endif /* __i386 */ 191 192 selector_t get_cs_register(); 193 194 #if !defined(__amd64) 195 196 /* 197 * User segment descriptors (code and data). 198 * Legacy mode 64-bits wide. 199 */ 200 typedef struct user_desc { 201 uint32_t usd_lolimit:16; /* segment limit 15:0 */ 202 uint32_t usd_lobase:16; /* segment base 15:0 */ 203 uint32_t usd_midbase:8; /* segment base 23:16 */ 204 uint32_t usd_type:5; /* segment type, includes S bit */ 205 uint32_t usd_dpl:2; /* segment descriptor priority level */ 206 uint32_t usd_p:1; /* segment descriptor present */ 207 uint32_t usd_hilimit:4; /* segment limit 19:16 */ 208 uint32_t usd_avl:1; /* available to sw, but not used */ 209 uint32_t usd_reserved:1; /* unused, ignored */ 210 uint32_t usd_def32:1; /* default 32 vs 16 bit operand */ 211 uint32_t usd_gran:1; /* limit units (bytes vs pages) */ 212 uint32_t usd_hibase:8; /* segment base 31:24 */ 213 } user_desc_t; 214 215 #define USEGD_GETBASE(usd) ((usd)->usd_lobase | \ 216 (usd)->usd_midbase << 16 | \ 217 (usd)->usd_hibase << (16 + 8)) 218 219 #define USEGD_SETBASE(usd, b) ((usd)->usd_lobase = (b), \ 220 (usd)->usd_midbase = (b) >> 16, \ 221 (usd)->usd_hibase = (b) >> (16 + 8)) 222 223 #define USEGD_GETLIMIT(usd) ((usd)->usd_lolimit | \ 224 (usd)->usd_hilimit << 16) 225 226 #define USEGD_SETLIMIT(usd, lim) ((usd)->usd_lolimit = lim, \ 227 (usd)->usd_hilimit = lim >> 16) 228 229 #define USD_TYPESHIFT 5 /* size of usd_type field */ 230 231 #else /* __amd64 */ 232 233 /* 234 * User segment descriptors. 235 * Long mode 64-bits wide. 236 * 237 * In 32-bit compatibility mode (%cs:usd_long=0) all fields are interpreted 238 * as in legacy mode for both code and data. 239 * 240 * In 64-bit mode (%cs:usd_long=1) code segments only have the conforming 241 * bit in usd_type, usd_dpl, usd_p, usd_long and usd_def32=0. usd_def32 242 * must be zero in 64-bit mode. Setting it to 1 is reserved for future use. 243 * All other fields are loaded but ignored by hardware. 244 * 245 * 64-bit data segments only have usd_p. All other fields are loaded but 246 * ignored by hardware when in 64-bit mode. 247 */ 248 typedef struct user_desc { 249 uint64_t usd_lolimit:16; /* segment limit 15:0 */ 250 uint64_t usd_lobase:16; /* segment base 15:0 */ 251 uint64_t usd_midbase:8; /* segment base 23:16 */ 252 uint64_t usd_type:5; /* segment type, includes S bit */ 253 uint64_t usd_dpl:2; /* segment descriptor priority level */ 254 uint64_t usd_p:1; /* segment descriptor present */ 255 uint64_t usd_hilimit:4; /* segment limit 19:16 */ 256 uint64_t usd_avl:1; /* available to sw, but not used */ 257 uint64_t usd_long:1; /* long mode (%cs only) */ 258 uint64_t usd_def32:1; /* default 32 vs 16 bit operand */ 259 uint64_t usd_gran:1; /* limit units (bytes vs page) */ 260 uint64_t usd_hibase:8; /* segment base 31:24 */ 261 } user_desc_t; 262 263 #define USEGD_GETBASE(usd) ((usd)->usd_lobase | \ 264 (usd)->usd_midbase << 16 | \ 265 (usd)->usd_hibase << (16 + 8)) 266 267 #define USEGD_SETBASE(usd, b) ((usd)->usd_lobase = (b), \ 268 (usd)->usd_midbase = (b) >> 16, \ 269 (usd)->usd_hibase = (b) >> (16 + 8)) 270 271 #define USEGD_GETLIMIT(usd) ((usd)->usd_lolimit | \ 272 (usd)->usd_hilimit << 16) 273 274 #define USEGD_SETLIMIT(usd, lim) ((usd)->usd_lolimit = lim, \ 275 (usd)->usd_hilimit = lim >> 16) 276 277 #define USD_TYPESHIFT 5 /* size of usd_type field */ 278 279 #endif /* __amd64 */ 280 281 #if !defined(__amd64) 282 283 /* 284 * System segment descriptors for LDT and TSS segments. 285 * Legacy mode 64-bits wide. 286 */ 287 typedef struct system_desc { 288 uint32_t ssd_lolimit:16; /* segment limit 15:0 */ 289 uint32_t ssd_lobase:16; /* segment base 15:0 */ 290 uint32_t ssd_midbase:8; /* segment base 23:16 */ 291 uint32_t ssd_type:4; /* segment type */ 292 uint32_t ssd_zero:1; /* must be zero */ 293 uint32_t ssd_dpl:2; /* segment descriptor priority level */ 294 uint32_t ssd_p:1; /* segment descriptor present */ 295 uint32_t ssd_hilimit:4; /* segment limit 19:16 */ 296 uint32_t ssd_avl:1; /* available to sw, but not used */ 297 uint32_t ssd_reserved:2; /* unused, ignored */ 298 uint32_t ssd_gran:1; /* limit unit (bytes vs pages) */ 299 uint32_t ssd_hibase:8; /* segment base 31:24 */ 300 } system_desc_t; 301 302 #else /* __amd64 */ 303 304 /* 305 * System segment descriptors for LDT and TSS segments. 306 * Long mode 128-bits wide. 307 * 308 * 32-bit LDT and TSS descriptor types are redefined to 64-bit equivalents. 309 * All other legacy types are reserved and illegal. 310 */ 311 typedef struct system_desc { 312 uint64_t ssd_lolimit:16; /* segment limit 15:0 */ 313 uint64_t ssd_lobase:16; /* segment base 15:0 */ 314 uint64_t ssd_midbase:8; /* segment base 23:16 */ 315 uint64_t ssd_type:4; /* segment type */ 316 uint64_t ssd_zero1:1; /* must be zero */ 317 uint64_t ssd_dpl:2; /* segment descriptor priority level */ 318 uint64_t ssd_p:1; /* segment descriptor present */ 319 uint64_t ssd_hilimit:4; /* segment limit 19:16 */ 320 uint64_t ssd_avl:1; /* available to sw, but not used */ 321 uint64_t ssd_resv1:2; /* unused, ignored */ 322 uint64_t ssd_gran:1; /* limit unit (bytes vs pages) */ 323 uint64_t ssd_hibase:8; /* segment base 31:24 */ 324 uint64_t ssd_hi64base:32; /* segment base 63:32 */ 325 uint64_t ssd_resv2:8; /* unused, ignored */ 326 uint64_t ssd_zero2:5; /* must be zero */ 327 uint64_t ssd_resv3:19; /* unused, ignored */ 328 } system_desc_t; 329 330 #endif /* __amd64 */ 331 332 #define SYSSEGD_SETLIMIT(ssd, lim) ((ssd)->ssd_lolimit = lim, \ 333 (ssd)->ssd_hilimit = lim >> 16) 334 335 #define SYSSEGD_GETLIMIT(ssd) (((ssd)->ssd_hilimit << 16) | \ 336 (ssd)->ssd_lolimit) 337 338 #if !defined(__amd64) 339 340 /* 341 * System gate segment descriptors for interrupt, trap, call and task gates. 342 * Legacy mode 64-bits wide. 343 */ 344 typedef struct gate_desc { 345 uint32_t sgd_looffset:16; /* segment code offset 15:0 */ 346 uint32_t sgd_selector:16; /* target code or task selector */ 347 uint32_t sgd_stkcpy:5; /* number of stack wds to cpy */ 348 uint32_t sgd_resv:3; /* unused, ignored */ 349 uint32_t sgd_type:5; /* segment type, includes S bit */ 350 uint32_t sgd_dpl:2; /* segment descriptor priority level */ 351 uint32_t sgd_p:1; /* segment descriptor present */ 352 uint32_t sgd_hioffset:16; /* code seg off 31:16 */ 353 } gate_desc_t; 354 355 #define GATESEG_GETOFFSET(sgd) ((uintptr_t)((sgd)->sgd_looffset | \ 356 (sgd)->sgd_hioffset << 16)) 357 358 #else /* __amd64 */ 359 360 /* 361 * System segment descriptors for interrupt, trap and call gates. 362 * Long mode 128-bits wide. 363 * 364 * 32-bit interrupt, trap and call gate types are redefined to 64-bit 365 * equivalents. Task gates along with all other legacy types are reserved 366 * and illegal. 367 */ 368 typedef struct gate_desc { 369 uint64_t sgd_looffset:16; /* segment code offset 15:0 */ 370 uint64_t sgd_selector:16; /* target code or task selector */ 371 uint64_t sgd_ist:3; /* IST table index */ 372 uint64_t sgd_resv1:5; /* unused, ignored */ 373 uint64_t sgd_type:5; /* segment type, includes S bit */ 374 uint64_t sgd_dpl:2; /* segment descriptor priority level */ 375 uint64_t sgd_p:1; /* segment descriptor present */ 376 uint64_t sgd_hioffset:16; /* segment code offset 31:16 */ 377 uint64_t sgd_hi64offset:32; /* segment code offset 63:32 */ 378 uint64_t sgd_resv2:8; /* unused, ignored */ 379 uint64_t sgd_zero:5; /* call gate only: must be zero */ 380 uint64_t sgd_resv3:19; /* unused, ignored */ 381 } gate_desc_t; 382 383 #define GATESEG_GETOFFSET(sgd) ((uintptr_t)((sgd)->sgd_looffset | \ 384 (sgd)->sgd_hioffset << 16 | \ 385 (uint64_t)((sgd)->sgd_hi64offset) << 32)) 386 387 #endif /* __amd64 */ 388 389 /* 390 * functions for initializing and updating segment descriptors. 391 */ 392 #if defined(__amd64) 393 394 extern void set_usegd(user_desc_t *, uint_t, void *, size_t, uint_t, uint_t, 395 uint_t, uint_t); 396 397 #elif defined(__i386) 398 399 extern void set_usegd(user_desc_t *, void *, size_t, uint_t, uint_t, 400 uint_t, uint_t); 401 402 #endif /* __i386 */ 403 404 extern void set_gatesegd(gate_desc_t *, void (*)(void), selector_t, 405 uint_t, uint_t, uint_t); 406 407 extern void set_syssegd(system_desc_t *, void *, size_t, uint_t, uint_t); 408 409 extern void *get_ssd_base(system_desc_t *); 410 411 extern void gdt_update_usegd(uint_t, user_desc_t *); 412 413 extern int ldt_update_segd(user_desc_t *, user_desc_t *); 414 415 #if defined(__xpv) 416 417 extern int xen_idt_to_trap_info(uint_t, gate_desc_t *, void *); 418 extern void xen_idt_write(gate_desc_t *, uint_t); 419 420 #endif /* __xen */ 421 422 void init_boot_gdt(user_desc_t *); 423 424 #endif /* _ASM */ 425 426 /* 427 * Common segment parameter defintions for granularity, default 428 * operand size and operaton mode. 429 */ 430 #define SDP_BYTES 0 /* segment limit scaled to bytes */ 431 #define SDP_PAGES 1 /* segment limit scaled to pages */ 432 #define SDP_OP32 1 /* code and data default operand = 32 bits */ 433 #define SDP_LONG 1 /* long mode code segment (64 bits) */ 434 #define SDP_SHORT 0 /* compat/legacy code segment (32 bits) */ 435 /* 436 * System segments and gate types. 437 * 438 * In long mode i386 32-bit ldt, tss, call, interrupt and trap gate 439 * types are redefined into 64-bit equivalents. 440 */ 441 #define SDT_SYSNULL 0 /* system null */ 442 #define SDT_SYS286TSS 1 /* system 286 TSS available */ 443 #define SDT_SYSLDT 2 /* system local descriptor table */ 444 #define SDT_SYS286BSY 3 /* system 286 TSS busy */ 445 #define SDT_SYS286CGT 4 /* system 286 call gate */ 446 #define SDT_SYSTASKGT 5 /* system task gate */ 447 #define SDT_SYS286IGT 6 /* system 286 interrupt gate */ 448 #define SDT_SYS286TGT 7 /* system 286 trap gate */ 449 #define SDT_SYSNULL2 8 /* system null again */ 450 #define SDT_SYSTSS 9 /* system TSS available */ 451 #define SDT_SYSNULL3 10 /* system null again */ 452 #define SDT_SYSTSSBSY 11 /* system TSS busy */ 453 #define SDT_SYSCGT 12 /* system call gate */ 454 #define SDT_SYSNULL4 13 /* system null again */ 455 #define SDT_SYSIGT 14 /* system interrupt gate */ 456 #define SDT_SYSTGT 15 /* system trap gate */ 457 458 /* 459 * Memory segment types. 460 * 461 * While in long mode expand-down, writable and accessed type field 462 * attributes are ignored. Only the conforming bit is loaded by hardware 463 * for long mode code segment descriptors. 464 */ 465 #define SDT_MEMRO 16 /* read only */ 466 #define SDT_MEMROA 17 /* read only accessed */ 467 #define SDT_MEMRW 18 /* read write */ 468 #define SDT_MEMRWA 19 /* read write accessed */ 469 #define SDT_MEMROD 20 /* read only expand dwn limit */ 470 #define SDT_MEMRODA 21 /* read only expand dwn limit accessed */ 471 #define SDT_MEMRWD 22 /* read write expand dwn limit */ 472 #define SDT_MEMRWDA 23 /* read write expand dwn limit accessed */ 473 #define SDT_MEME 24 /* execute only */ 474 #define SDT_MEMEA 25 /* execute only accessed */ 475 #define SDT_MEMER 26 /* execute read */ 476 #define SDT_MEMERA 27 /* execute read accessed */ 477 #define SDT_MEMEC 28 /* execute only conforming */ 478 #define SDT_MEMEAC 29 /* execute only accessed conforming */ 479 #define SDT_MEMERC 30 /* execute read conforming */ 480 #define SDT_MEMERAC 31 /* execute read accessed conforming */ 481 482 /* 483 * Entries in the Interrupt Descriptor Table (IDT) 484 */ 485 #define IDT_DE 0 /* #DE: Divide Error */ 486 #define IDT_DB 1 /* #DB: Debug */ 487 #define IDT_NMI 2 /* Nonmaskable External Interrupt */ 488 #define IDT_BP 3 /* #BP: Breakpoint */ 489 #define IDT_OF 4 /* #OF: Overflow */ 490 #define IDT_BR 5 /* #BR: Bound Range Exceeded */ 491 #define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */ 492 #define IDT_NM 7 /* #NM: No Math Coprocessor */ 493 #define IDT_DF 8 /* #DF: Double Fault */ 494 #define IDT_FPUGP 9 /* Coprocessor Segment Overrun */ 495 #define IDT_TS 10 /* #TS: Invalid TSS */ 496 #define IDT_NP 11 /* #NP: Segment Not Present */ 497 #define IDT_SS 12 /* #SS: Stack Segment Fault */ 498 #define IDT_GP 13 /* #GP: General Protection Fault */ 499 #define IDT_PF 14 /* #PF: Page Fault */ 500 #define IDT_MF 16 /* #MF: FPU Floating-Point Error */ 501 #define IDT_AC 17 /* #AC: Alignment Check */ 502 #define IDT_MC 18 /* #MC: Machine Check */ 503 #define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */ 504 #define NIDT 256 /* size in entries of IDT */ 505 506 /* 507 * Entries in the Global Descriptor Table (GDT) 508 * 509 * We make sure to space the system descriptors (LDT's, TSS') 510 * such that they are double gdt slot aligned. This is because 511 * in long mode system segment decriptors expand to 128 bits. 512 * 513 * GDT_LWPFS and GDT_LWPGS must be the same for both 32 and 64-bit 514 * kernels. See setup_context in libc. 64-bit processes must set 515 * %fs or %gs to null selector to use 64-bit fsbase or gsbase 516 * respectively. 517 */ 518 #define GDT_NULL 0 /* null */ 519 #define GDT_B32DATA 1 /* dboot 32 bit data descriptor */ 520 #define GDT_B32CODE 2 /* dboot 32 bit code descriptor */ 521 #define GDT_B16CODE 3 /* bios call 16 bit code descriptor */ 522 #define GDT_B16DATA 4 /* bios call 16 bit data descriptor */ 523 #define GDT_B64CODE 5 /* dboot 64 bit code descriptor */ 524 #define GDT_BGSTMP 7 /* kmdb descriptor only used early in boot */ 525 526 #if defined(__amd64) 527 528 #define GDT_KCODE 6 /* kernel code seg %cs */ 529 #define GDT_KDATA 7 /* kernel data seg %ds */ 530 #define GDT_U32CODE 8 /* 32-bit process on 64-bit kernel %cs */ 531 #define GDT_UDATA 9 /* user data seg %ds (32 and 64 bit) */ 532 #define GDT_UCODE 10 /* native user code seg %cs */ 533 #define GDT_LDT 12 /* LDT for current process */ 534 #define GDT_KTSS 14 /* kernel tss */ 535 #define GDT_FS GDT_NULL /* kernel %fs segment selector */ 536 #define GDT_GS GDT_NULL /* kernel %gs segment selector */ 537 #define GDT_LWPFS 55 /* lwp private %fs segment selector (32-bit) */ 538 #define GDT_LWPGS 56 /* lwp private %gs segment selector (32-bit) */ 539 #define GDT_BRANDMIN 57 /* first entry in GDT for brand usage */ 540 #define GDT_BRANDMAX 61 /* last entry in GDT for brand usage */ 541 #define NGDT 62 /* number of entries in GDT */ 542 543 /* 544 * This selector is only used in the temporary GDT used to bring additional 545 * CPUs from 16-bit real mode into long mode in real_mode_start(). 546 */ 547 #define TEMPGDT_KCODE64 1 /* 64-bit code selector */ 548 549 #elif defined(__i386) 550 551 #define GDT_LDT 40 /* LDT for current process */ 552 #define GDT_KTSS 42 /* kernel tss */ 553 #define GDT_KCODE 43 /* kernel code seg %cs */ 554 #define GDT_KDATA 44 /* kernel data seg %ds */ 555 #define GDT_UCODE 45 /* native user code seg %cs */ 556 #define GDT_UDATA 46 /* user data seg %ds (32 and 64 bit) */ 557 #define GDT_DBFLT 47 /* double fault #DF selector */ 558 #define GDT_FS 53 /* kernel %fs segment selector */ 559 #define GDT_GS 54 /* kernel %gs segment selector */ 560 #define GDT_LWPFS 55 /* lwp private %fs segment selector */ 561 #define GDT_LWPGS 56 /* lwp private %gs segment selector */ 562 #define GDT_BRANDMIN 57 /* first entry in GDT for brand usage */ 563 #define GDT_BRANDMAX 61 /* last entry in GDT for brand usage */ 564 #if !defined(__xpv) 565 #define NGDT 90 /* number of entries in GDT */ 566 #else 567 #define NGDT 512 /* single 4K page for the hypervisor */ 568 #endif 569 570 #endif /* __i386 */ 571 572 /* 573 * Convenient selector definitions. 574 */ 575 576 /* 577 * XXPV 64 bit Xen only allows the guest %cs/%ss be the private ones it 578 * provides, not the ones we create for ourselves. See FLAT_RING3_CS64 in 579 * public/arch-x86_64.h 580 * 581 * 64-bit Xen runs paravirtual guests in ring 3 but emulates them running in 582 * ring 0 by clearing CPL in %cs value pushed on guest exception stacks. 583 * Therefore we will have KCS_SEL value indicate ring 0 and use that everywhere 584 * in the kernel. But in the few files where we initialize segment registers or 585 * create and update descriptors we will explicity OR in SEL_KPL (ring 3) for 586 * kernel %cs. See desctbls.c for an example. 587 */ 588 589 #if defined(__xpv) && defined(__amd64) 590 #define KCS_SEL 0xe030 /* FLAT_RING3_CS64 & 0xFFF0 */ 591 #define KDS_SEL 0xe02b /* FLAT_RING3_SS64 */ 592 #else 593 #define KCS_SEL SEL_GDT(GDT_KCODE, SEL_KPL) 594 #define KDS_SEL SEL_GDT(GDT_KDATA, SEL_KPL) 595 #endif 596 597 #define UCS_SEL SEL_GDT(GDT_UCODE, SEL_UPL) 598 #if defined(__amd64) 599 #define TEMP_CS64_SEL SEL_GDT(TEMPGDT_KCODE64, SEL_KPL) 600 #define U32CS_SEL SEL_GDT(GDT_U32CODE, SEL_UPL) 601 #endif 602 603 #define UDS_SEL SEL_GDT(GDT_UDATA, SEL_UPL) 604 #define ULDT_SEL SEL_GDT(GDT_LDT, SEL_KPL) 605 #define KTSS_SEL SEL_GDT(GDT_KTSS, SEL_KPL) 606 #define DFTSS_SEL SEL_GDT(GDT_DBFLT, SEL_KPL) 607 #define KFS_SEL 0 608 #define KGS_SEL SEL_GDT(GDT_GS, SEL_KPL) 609 #define LWPFS_SEL SEL_GDT(GDT_LWPFS, SEL_UPL) 610 #define LWPGS_SEL SEL_GDT(GDT_LWPGS, SEL_UPL) 611 #define BRANDMIN_SEL SEL_GDT(GDT_BRANDMIN, SEL_UPL) 612 #define BRANDMAX_SEL SEL_GDT(GDT_BRANDMAX, SEL_UPL) 613 614 #define B64CODE_SEL SEL_GDT(GDT_B64CODE, SEL_KPL) 615 #define B32CODE_SEL SEL_GDT(GDT_B32CODE, SEL_KPL) 616 #define B32DATA_SEL SEL_GDT(GDT_B32DATA, SEL_KPL) 617 #define B16CODE_SEL SEL_GDT(GDT_B16CODE, SEL_KPL) 618 #define B16DATA_SEL SEL_GDT(GDT_B16DATA, SEL_KPL) 619 620 /* 621 * Temporary %gs descriptor used by kmdb with -d option. Only lives 622 * in boot's GDT and is not copied into kernel's GDT from boot. 623 */ 624 #define KMDBGS_SEL SEL_GDT(GDT_BGSTMP, SEL_KPL) 625 626 /* 627 * Selector used for kdi_idt when kmdb has taken over the IDT. 628 */ 629 #if defined(__amd64) 630 #define KMDBCODE_SEL B64CODE_SEL 631 #else 632 #define KMDBCODE_SEL B32CODE_SEL 633 #endif 634 635 /* 636 * Entries in default Local Descriptor Table (LDT) for every process. 637 */ 638 #define LDT_SYSCALL 0 /* call gate for libc.a (obsolete) */ 639 #define LDT_SIGCALL 1 /* EOL me, call gate for static sigreturn */ 640 #define LDT_RESVD1 2 /* old user %cs */ 641 #define LDT_RESVD2 3 /* old user %ds */ 642 #define LDT_ALTSYSCALL 4 /* alternate call gate for system calls */ 643 #define LDT_ALTSIGCALL 5 /* EOL me, alternate call gate for sigreturn */ 644 #define LDT_UDBASE 6 /* user descriptor base index */ 645 #define MINNLDT 512 /* Current min solaris ldt size (1 4K page) */ 646 #define MAXNLDT 8192 /* max solaris ldt size (16 4K pages) */ 647 648 #ifndef _ASM 649 650 extern gate_desc_t *idt0; 651 extern desctbr_t idt0_default_reg; 652 extern user_desc_t *gdt0; 653 654 extern user_desc_t zero_udesc; 655 extern user_desc_t null_udesc; 656 extern system_desc_t null_sdesc; 657 658 #if defined(__amd64) 659 extern user_desc_t zero_u32desc; 660 #endif 661 #if defined(__amd64) 662 extern user_desc_t ucs_on; 663 extern user_desc_t ucs_off; 664 extern user_desc_t ucs32_on; 665 extern user_desc_t ucs32_off; 666 #endif /* __amd64 */ 667 668 extern tss_t *ktss0; 669 670 #if defined(__i386) 671 extern tss_t *dftss0; 672 #endif /* __i386 */ 673 674 extern void div0trap(), dbgtrap(), nmiint(), brktrap(), ovflotrap(); 675 extern void boundstrap(), invoptrap(), ndptrap(); 676 #if !defined(__xpv) 677 extern void syserrtrap(); 678 #endif 679 extern void invaltrap(), invtsstrap(), segnptrap(), stktrap(); 680 extern void gptrap(), pftrap(), ndperr(); 681 extern void overrun(), resvtrap(); 682 extern void _start(), cmnint(); 683 extern void achktrap(), mcetrap(); 684 extern void xmtrap(); 685 extern void fasttrap(); 686 extern void dtrace_ret(); 687 688 #if !defined(__amd64) 689 extern void pentium_pftrap(); 690 #endif 691 692 #endif /* _ASM */ 693 694 #ifdef __cplusplus 695 } 696 #endif 697 698 #endif /* _SYS_SEGMENTS_H */ 699