arch/x86/include/sys/segments.h

   1 /*
   2  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
   3  */
   4 /*
   5  * Copyright 2016 Joyent, Inc.
   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 #define GDT_CPUID       16      /* store numeric id of current CPU */
 526
 527 #if defined(__amd64)
 528
 529 #define GDT_KCODE       6       /* kernel code seg %cs */
 530 #define GDT_KDATA       7       /* kernel data seg %ds */
 531 #define GDT_U32CODE     8       /* 32-bit process on 64-bit kernel %cs */
 532 #define GDT_UDATA       9       /* user data seg %ds (32 and 64 bit) */
 533 #define GDT_UCODE       10      /* native user code  seg %cs */
 534 #define GDT_LDT         12      /* (12-13) LDT for current process */
 535 #define GDT_KTSS        14      /* (14-15) kernel tss */
 536 #define GDT_FS          GDT_NULL /* kernel %fs segment selector */
 537 #define GDT_GS          GDT_NULL /* kernel %gs segment selector */
 538 #define GDT_LWPFS       55      /* lwp private %fs segment selector (32-bit) */
 539 #define GDT_LWPGS       56      /* lwp private %gs segment selector (32-bit) */
 540 #define GDT_BRANDMIN    57      /* first entry in GDT for brand usage */
 541 #define GDT_BRANDMAX    61      /* last entry in GDT for brand usage */
 542 #define NGDT            62      /* number of entries in GDT */
 543
 544 /*
 545  * This selector is only used in the temporary GDT used to bring additional
 546  * CPUs from 16-bit real mode into long mode in real_mode_start().
 547  */
 548 #define TEMPGDT_KCODE64 1       /* 64-bit code selector */
 549
 550 #elif defined(__i386)
 551
 552 #define GDT_LDT         40      /* LDT for current process */
 553 #define GDT_KTSS        42      /* kernel tss */
 554 #define GDT_KCODE       43      /* kernel code seg %cs */
 555 #define GDT_KDATA       44      /* kernel data seg %ds */
 556 #define GDT_UCODE       45      /* native user code  seg %cs */
 557 #define GDT_UDATA       46      /* user data seg %ds (32 and 64 bit) */
 558 #define GDT_DBFLT       47      /* double fault #DF selector */
 559 #define GDT_FS          53      /* kernel %fs segment selector */
 560 #define GDT_GS          54      /* kernel %gs segment selector */
 561 #define GDT_LWPFS       55      /* lwp private %fs segment selector */
 562 #define GDT_LWPGS       56      /* lwp private %gs segment selector */
 563 #define GDT_BRANDMIN    57      /* first entry in GDT for brand usage */
 564 #define GDT_BRANDMAX    61      /* last entry in GDT for brand usage */
 565 #if !defined(__xpv)
 566 #define NGDT            90      /* number of entries in GDT */
 567 #else
 568 #define NGDT            512     /* single 4K page for the hypervisor */
 569 #endif
 570
 571 #endif  /* __i386 */
 572
 573 /*
 574  * Convenient selector definitions.
 575  */
 576
 577 /*
 578  * XXPV 64 bit Xen only allows the guest %cs/%ss be the private ones it
 579  * provides, not the ones we create for ourselves.  See FLAT_RING3_CS64 in
 580  * public/arch-x86_64.h
 581  *
 582  * 64-bit Xen runs paravirtual guests in ring 3 but emulates them running in
 583  * ring 0 by clearing CPL in %cs value pushed on guest exception stacks.
 584  * Therefore we will have KCS_SEL value indicate ring 0 and use that everywhere
 585  * in the kernel. But in the few files where we initialize segment registers or
 586  * create and update descriptors we will explicity OR in SEL_KPL (ring 3) for
 587  * kernel %cs. See desctbls.c for an example.
 588  */
 589
 590 #if defined(__xpv) && defined(__amd64)
 591 #define KCS_SEL         0xe030          /* FLAT_RING3_CS64 & 0xFFF0 */
 592 #define KDS_SEL         0xe02b          /* FLAT_RING3_SS64 */
 593 #else
 594 #define KCS_SEL         SEL_GDT(GDT_KCODE, SEL_KPL)
 595 #define KDS_SEL         SEL_GDT(GDT_KDATA, SEL_KPL)
 596 #endif
 597
 598 #define UCS_SEL         SEL_GDT(GDT_UCODE, SEL_UPL)
 599 #if defined(__amd64)
 600 #define TEMP_CS64_SEL   SEL_GDT(TEMPGDT_KCODE64, SEL_KPL)
 601 #define U32CS_SEL       SEL_GDT(GDT_U32CODE, SEL_UPL)
 602 #endif
 603
 604 #define UDS_SEL         SEL_GDT(GDT_UDATA, SEL_UPL)
 605 #define ULDT_SEL        SEL_GDT(GDT_LDT, SEL_KPL)
 606 #define KTSS_SEL        SEL_GDT(GDT_KTSS, SEL_KPL)
 607 #define DFTSS_SEL       SEL_GDT(GDT_DBFLT, SEL_KPL)
 608 #define KFS_SEL         0
 609 #define KGS_SEL         SEL_GDT(GDT_GS, SEL_KPL)
 610 #define LWPFS_SEL       SEL_GDT(GDT_LWPFS, SEL_UPL)
 611 #define LWPGS_SEL       SEL_GDT(GDT_LWPGS, SEL_UPL)
 612 #define BRANDMIN_SEL    SEL_GDT(GDT_BRANDMIN, SEL_UPL)
 613 #define BRANDMAX_SEL    SEL_GDT(GDT_BRANDMAX, SEL_UPL)
 614
 615 #define B64CODE_SEL     SEL_GDT(GDT_B64CODE, SEL_KPL)
 616 #define B32CODE_SEL     SEL_GDT(GDT_B32CODE, SEL_KPL)
 617 #define B32DATA_SEL     SEL_GDT(GDT_B32DATA, SEL_KPL)
 618 #define B16CODE_SEL     SEL_GDT(GDT_B16CODE, SEL_KPL)
 619 #define B16DATA_SEL     SEL_GDT(GDT_B16DATA, SEL_KPL)
 620
 621 /*
 622  * Temporary %gs descriptor used by kmdb with -d option. Only lives
 623  * in boot's GDT and is not copied into kernel's GDT from boot.
 624  */
 625 #define KMDBGS_SEL      SEL_GDT(GDT_BGSTMP, SEL_KPL)
 626
 627 /*
 628  * Selector used for kdi_idt when kmdb has taken over the IDT.
 629  */
 630 #if defined(__amd64)
 631 #define KMDBCODE_SEL    B64CODE_SEL
 632 #else
 633 #define KMDBCODE_SEL    B32CODE_SEL
 634 #endif
 635
 636 /*
 637  * Entries in default Local Descriptor Table (LDT) for every process.
 638  */
 639 #define LDT_SYSCALL     0       /* call gate for libc.a (obsolete) */
 640 #define LDT_SIGCALL     1       /* EOL me, call gate for static sigreturn */
 641 #define LDT_RESVD1      2       /* old user %cs */
 642 #define LDT_RESVD2      3       /* old user %ds */
 643 #define LDT_ALTSYSCALL  4       /* alternate call gate for system calls */
 644 #define LDT_ALTSIGCALL  5       /* EOL me, alternate call gate for sigreturn */
 645 #define LDT_UDBASE      6       /* user descriptor base index */
 646 #define MINNLDT         512     /* Current min solaris ldt size (1 4K page) */
 647 #define MAXNLDT         8192    /* max solaris ldt size (16 4K pages) */
 648
 649 #ifndef _ASM
 650
 651 extern  gate_desc_t     *idt0;
 652 extern  desctbr_t       idt0_default_reg;
 653 extern  user_desc_t     *gdt0;
 654
 655 extern user_desc_t      zero_udesc;
 656 extern user_desc_t      null_udesc;
 657 extern system_desc_t    null_sdesc;
 658
 659 #if defined(__amd64)
 660 extern user_desc_t      zero_u32desc;
 661 #endif
 662 #if defined(__amd64)
 663 extern user_desc_t      ucs_on;
 664 extern user_desc_t      ucs_off;
 665 extern user_desc_t      ucs32_on;
 666 extern user_desc_t      ucs32_off;
 667 #endif  /* __amd64 */
 668
 669 extern tss_t *ktss0;
 670
 671 #if defined(__i386)
 672 extern tss_t *dftss0;
 673 #endif  /* __i386 */
 674
 675 extern void div0trap(), dbgtrap(), nmiint(), brktrap(), ovflotrap();
 676 extern void boundstrap(), invoptrap(), ndptrap();
 677 #if !defined(__xpv)
 678 extern void syserrtrap();
 679 #endif
 680 extern void invaltrap(), invtsstrap(), segnptrap(), stktrap();
 681 extern void gptrap(), pftrap(), ndperr();
 682 extern void overrun(), resvtrap();
 683 extern void _start(), cmnint();
 684 extern void achktrap(), mcetrap();
 685 extern void xmtrap();
 686 extern void fasttrap();
 687 extern void dtrace_ret();
 688
 689 #if !defined(__amd64)
 690 extern void pentium_pftrap();
 691 #endif
 692
 693 #endif /* _ASM */
 694
 695 #ifdef  __cplusplus
 696 }
 697 #endif
 698
 699 #endif /* _SYS_SEGMENTS_H */