osfmk/i386/seg.h

   1 /*
   2  * Copyright (c) 2000-2009 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 #ifndef _I386_SEG_H_
  57 #define _I386_SEG_H_
  58 #ifdef MACH_KERNEL
  59 #include <mach_kdb.h>
  60 #else
  61 #define MACH_KDB 0
  62 #endif  /* MACH_KERNEL */
  63 #ifndef __ASSEMBLER__
  64 #include <stdint.h>
  65 #include <mach/vm_types.h>
  66 #include <architecture/i386/sel.h>
  67
  68 /*
  69  * i386 segmentation.
  70  */
  71
  72 static inline uint16_t
  73 sel_to_selector(sel_t   sel)
  74 {
  75     union {
  76         sel_t           sel;
  77         uint16_t        selector;
  78     } tconv;
  79
  80     tconv.sel = sel;
  81
  82     return (tconv.selector);
  83 }
  84
  85 static inline sel_t
  86 selector_to_sel(uint16_t selector)
  87 {
  88     union {
  89         uint16_t        selector;
  90         sel_t           sel;
  91     } tconv;
  92
  93     tconv.selector = selector;
  94
  95     return (tconv.sel);
  96 }
  97
  98 #define LDTSZ           8192            /* size of the kernel ldt in entries */
  99 #define LDTSZ_MIN       SEL_TO_INDEX(USER_SETTABLE)
 100                                         /* kernel ldt entries */
 101
 102 #if     MACH_KDB
 103 #define GDTSZ           20
 104 #else
 105 #define GDTSZ           19
 106 #endif
 107
 108 #ifdef __x86_64__
 109 #define PROT_MODE_GDT_SIZE 48 /* size of prot_mode_gdt in bytes */
 110 #endif
 111
 112 /*
 113  * Interrupt table is always 256 entries long.
 114  */
 115 #define IDTSZ           256
 116
 117 #include <sys/cdefs.h>
 118
 119 /*
 120  * Real segment descriptor.
 121  */
 122 struct real_descriptor {
 123         uint32_t        limit_low:16,   /* limit 0..15 */
 124                         base_low:16,    /* base  0..15 */
 125                         base_med:8,     /* base  16..23 */
 126                         access:8,       /* access byte */
 127                         limit_high:4,   /* limit 16..19 */
 128                         granularity:4,  /* granularity */
 129                         base_high:8;    /* base 24..31 */
 130 };
 131 struct real_descriptor64 {
 132         uint32_t        limit_low16:16, /* limit 0..15 */
 133                         base_low16:16,  /* base  0..15 */
 134                         base_med8:8,    /* base  16..23 */
 135                         access8:8,      /* access byte */
 136                         limit_high4:4,  /* limit 16..19 */
 137                         granularity4:4, /* granularity */
 138                         base_high8:8,   /* base 24..31 */
 139                         base_top32:32,  /* base 32..63 */
 140                         reserved32:32;  /* reserved/zero */
 141 };
 142 struct real_gate {
 143         uint32_t        offset_low:16,  /* offset 0..15 */
 144                         selector:16,
 145                         word_count:8,
 146                         access:8,
 147                         offset_high:16; /* offset 16..31 */
 148 };
 149 struct real_gate64 {
 150         uint32_t        offset_low16:16,        /* offset 0..15 */
 151                         selector16:16,
 152                         IST:3,
 153                         zeroes5:5,
 154                         access8:8,
 155                         offset_high16:16,       /* offset 16..31 */
 156                         offset_top32:32,        /* offset 32..63 */
 157                         reserved32:32;          /* reserved/zero */
 158 };
 159
 160 #define MAKE_REAL_DESCRIPTOR(base,lim,gran,acc) { \
 161         .limit_low = lim & 0xffff, \
 162         .limit_high = (lim >> 16) & 0xf, \
 163         .base_low = base & 0xffff, \
 164         .base_med = (base >> 16) & 0xff, \
 165         .base_high = (base >> 24) & 0xff, \
 166         .access = acc, \
 167         .granularity = gran \
 168 }
 169
 170 /*
 171  * We build descriptors and gates in a 'fake' format to let the
 172  * fields be contiguous.  We shuffle them into the real format
 173  * at runtime.
 174  */
 175 struct fake_descriptor {
 176         uint32_t        offset:32;              /* offset */
 177         uint32_t        lim_or_seg:20;          /* limit */
 178                                                 /* or segment, for gate */
 179         uint32_t        size_or_wdct:4;         /* size/granularity */
 180                                                 /* word count, for gate */
 181         uint32_t        access:8;               /* access */
 182 };
 183 struct fake_descriptor64 {
 184         uint64_t        offset64;               /* offset [0..31,32..63] */
 185         uint32_t        lim_or_seg:20;          /* limit */
 186                                                 /* or segment, for gate */
 187         uint32_t        size_or_IST:4;          /* size/granularity */
 188                                                 /* IST for gates */
 189         uint32_t        access:8;               /* access */
 190         uint32_t        reserved:32;            /* reserved/zero */
 191 };
 192 #ifdef __i386__
 193 #define FAKE_UBER64(addr32)     { (uint32_t) (addr32), KERNEL_UBER_BASE_HI32 }
 194 #define FAKE_COMPAT(addr32)     { (uint32_t) (addr32), 0x0 }
 195 #define UBER64(addr32)          ((addr64_t) (uintptr_t)addr32 + KERNEL_UBER_BASE)
 196 #endif
 197
 198 /*
 199  * Boot-time data for master (or only) CPU
 200  */
 201 extern struct fake_descriptor   master_idt[IDTSZ];
 202 extern struct real_descriptor   master_gdt[GDTSZ];
 203 extern struct real_descriptor   master_ldt[LDTSZ];
 204 extern struct i386_tss          master_ktss;
 205 extern struct sysenter_stack    master_sstk;
 206
 207 extern struct fake_descriptor64 master_idt64[IDTSZ];
 208 extern struct x86_64_tss        master_ktss64;
 209
 210 __BEGIN_DECLS
 211
 212 extern char                     df_task_stack[];
 213 extern char                     df_task_stack_end[];
 214 extern struct i386_tss          master_dftss;
 215 extern void                     df_task_start(void);
 216
 217 extern char                     mc_task_stack[];
 218 extern char                     mc_task_stack_end[];
 219 extern struct i386_tss          master_mctss;
 220 extern void                     mc_task_start(void);
 221
 222 #if     MACH_KDB
 223 extern char                     db_task_stack_store[];
 224 extern struct i386_tss          master_dbtss;
 225 extern void                     db_task_start(void);
 226 #endif  /* MACH_KDB */
 227
 228 __END_DECLS
 229
 230 #endif  /*__ASSEMBLER__*/
 231
 232 #define SZ_64           0x2                     /* 64-bit segment */
 233 #define SZ_32           0x4                     /* 32-bit segment */
 234 #define SZ_G            0x8                     /* 4K limit field */
 235
 236 #define ACC_A           0x01                    /* accessed */
 237 #define ACC_TYPE        0x1e                    /* type field: */
 238
 239 #define ACC_TYPE_SYSTEM 0x00                    /* system descriptors: */
 240
 241 #define ACC_LDT         0x02                        /* LDT */
 242 #define ACC_CALL_GATE_16 0x04                       /* 16-bit call gate */
 243 #define ACC_TASK_GATE   0x05                        /* task gate */
 244 #define ACC_TSS         0x09                        /* task segment */
 245 #define ACC_CALL_GATE   0x0c                        /* call gate */
 246 #define ACC_INTR_GATE   0x0e                        /* interrupt gate */
 247 #define ACC_TRAP_GATE   0x0f                        /* trap gate */
 248
 249 #define ACC_TSS_BUSY    0x02                        /* task busy */
 250
 251 #define ACC_TYPE_USER   0x10                    /* user descriptors */
 252
 253 #define ACC_DATA        0x10                        /* data */
 254 #define ACC_DATA_W      0x12                        /* data, writable */
 255 #define ACC_DATA_E      0x14                        /* data, expand-down */
 256 #define ACC_DATA_EW     0x16                        /* data, expand-down,
 257                                                              writable */
 258 #define ACC_CODE        0x18                        /* code */
 259 #define ACC_CODE_R      0x1a                        /* code, readable */
 260 #define ACC_CODE_C      0x1c                        /* code, conforming */
 261 #define ACC_CODE_CR     0x1e                        /* code, conforming,
 262                                                        readable */
 263 #define ACC_PL          0x60                    /* access rights: */
 264 #define ACC_PL_K        0x00                    /* kernel access only */
 265 #define ACC_PL_U        0x60                    /* user access */
 266 #define ACC_P           0x80                    /* segment present */
 267
 268 /*
 269  * Components of a selector
 270  */
 271 #define SEL_LDTS        0x04                    /* local selector */
 272 #define SEL_PL          0x03                    /* privilege level: */
 273 #define SEL_PL_K        0x00                        /* kernel selector */
 274 #define SEL_PL_U        0x03                        /* user selector */
 275
 276 /*
 277  * Convert selector to descriptor table index.
 278  */
 279 #define sel_idx(sel)    (selector_to_sel(sel).index)
 280 #define SEL_TO_INDEX(s) ((s)>>3)
 281
 282 #define NULL_SEG        0
 283
 284 #ifdef __i386__
 285 /*
 286  * User descriptors for MACH - 32-bit flat address space
 287  */
 288 #define SYSENTER_CS     0x07            /* sysenter kernel code segment */
 289 #define SYSENTER_DS     0x0f            /* sysenter kernel data segment */
 290 #define USER_CS         0x17            /* user code segment
 291                                            Must be SYSENTER_CS+16 for sysexit */
 292 /* Special case: sysenter with EFL_TF (trace bit) set - use iret not sysexit */
 293 #define SYSENTER_TF_CS  (USER_CS|0x10000)
 294 #define USER_DS         0x1f            /* user data segment
 295                                            Must be SYSENTER_CS+24 for sysexit */
 296 #define USER64_CS       0x27            /* 64-bit user code segment
 297                                            Must be USER_CS+16 for sysret */
 298 #define USER64_DS       USER_DS         /* 64-bit user data segment == 32-bit */
 299 #define SYSCALL_CS      0x2f            /* 64-bit syscall pseudo-segment */
 300 #define USER_CTHREAD    0x37            /* user cthread area */
 301 #define USER_SETTABLE   0x3f            /* start of user settable ldt entries */
 302
 303 /*
 304  * Kernel descriptors for MACH - 32-bit flat address space.
 305  */
 306 #define KERNEL32_CS     0x08            /* kernel code */
 307 #define KERNEL_DS       0x10            /* kernel data */
 308 #define KERNEL_LDT      0x18            /* master LDT */
 309 #define KERNEL_LDT_2    0x20            /* master LDT expanded for 64-bit */
 310 #define KERNEL_TSS      0x28            /* master TSS */
 311 #define KERNEL_TSS_2    0x30            /* master TSS expanded for 64-bit */
 312
 313 #define MC_TSS          0x38            /* machine-check handler TSS */
 314
 315 #define CPU_DATA_GS     0x48            /* per-cpu data */
 316
 317 #define DF_TSS          0x50            /* double-fault handler TSS */
 318
 319 #define USER_LDT        0x58
 320 #define USER_TSS        0x60
 321 #define FPE_CS          0x68
 322
 323 #else // __x86_64__
 324
 325 /*
 326  * Kernel descriptors for MACH - 64-bit flat address space.
 327  */
 328 #define KERNEL64_CS     0x08            /* 1:  K64 code */
 329 #define SYSENTER_CS     0x0b            /*     U32 sysenter pseudo-segment */
 330 #define KERNEL64_SS     0x10            /* 2:  KERNEL64_CS+8 for syscall */
 331 #define USER_CS         0x1b            /* 3:  U32 code */
 332 #define USER_DS         0x23            /* 4:  USER_CS+8 for sysret */
 333 #define USER64_CS       0x2b            /* 5:  USER_CS+16 for sysret */
 334 #define USER64_DS       USER_DS         /*     U64 data pseudo-segment */
 335 #define KERNEL_LDT      0x30            /* 6:  */
 336                                         /* 7:  other 8 bytes of KERNEL_LDT */
 337 #define KERNEL_TSS      0x40            /* 8:  */
 338                                         /* 9:  other 8 bytes of KERNEL_TSS */
 339 #define KERNEL32_CS     0x50            /* 10: */
 340 #define USER_LDT        0x58            /* 11: */
 341                                         /* 12: other 8 bytes of USER_LDT */
 342 #define KERNEL_DS       0x68            /* 13: 32-bit kernel data */
 343
 344 #endif
 345
 346 #ifdef __i386__
 347 #if !defined(USER_WINDOW_SEL)
 348 #define USER_WINDOW_SEL 0x70            /* 14:  window for copyin/copyout */
 349 #define PHYS_WINDOW_SEL 0x78            /* 15:  window for copyin/copyout */
 350 #endif
 351 #define KERNEL64_CS     0x80            /* 16:  kernel 64-bit code */
 352 #define KERNEL64_SS     0x88            /* 17:  kernel 64-bit (syscall) stack */
 353 #else // __x86_64__
 354 #define SYSENTER_TF_CS  (USER_CS|0x10000)
 355 #define SYSENTER_DS     KERNEL64_SS     /* sysenter kernel data segment */
 356 #endif
 357
 358 #if     MACH_KDB
 359 #define DEBUG_TSS       0x90            /* 18:  debug TSS (uniprocessor) */
 360 #endif
 361
 362 #ifdef __x86_64__
 363 /*
 364  * 64-bit kernel LDT descriptors
 365  */
 366 #define SYSCALL_CS      0x07            /* syscall pseudo-segment */
 367 #define USER_CTHREAD    0x0f            /* user cthread area */
 368 #define USER_SETTABLE   0x1f            /* start of user settable ldt entries */
 369 #endif
 370
 371 #endif  /* _I386_SEG_H_ */