osfmk/i386/seg.h

   1 /*
   2  * Copyright (c) 2000-2006 Apple Computer, 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
  59 #include <mach_kdb.h>
  60 #ifndef ASSEMBLER
  61 #include <stdint.h>
  62 #include <mach/vm_types.h>
  63 #include <architecture/i386/sel.h>
  64
  65 /*
  66  * i386 segmentation.
  67  */
  68
  69 static inline uint16_t
  70 sel_to_selector(sel_t   sel)
  71 {
  72     union {
  73         sel_t           sel;
  74         uint16_t        selector;
  75     } tconv;
  76
  77     tconv.sel = sel;
  78
  79     return (tconv.selector);
  80 }
  81
  82 static inline sel_t
  83 selector_to_sel(uint16_t selector)
  84 {
  85     union {
  86         uint16_t        selector;
  87         sel_t           sel;
  88     } tconv;
  89
  90     tconv.selector = selector;
  91
  92     return (tconv.sel);
  93 }
  94
  95 #define LDTSZ           8192            /* size of the kernel ldt in entries */
  96 #define LDTSZ_MIN       SEL_TO_INDEX(USER_SETTABLE)
  97                                         /* kernel ldt entries */
  98
  99 #if     MACH_KDB
 100 #define GDTSZ           19
 101 #else
 102 #define GDTSZ           18
 103 #endif
 104
 105 /*
 106  * Interrupt table is always 256 entries long.
 107  */
 108 #define IDTSZ           256
 109
 110 #include <sys/cdefs.h>
 111
 112 /*
 113  * Real segment descriptor.
 114  */
 115 struct real_descriptor {
 116         uint32_t        limit_low:16,   /* limit 0..15 */
 117                         base_low:16,    /* base  0..15 */
 118                         base_med:8,     /* base  16..23 */
 119                         access:8,       /* access byte */
 120                         limit_high:4,   /* limit 16..19 */
 121                         granularity:4,  /* granularity */
 122                         base_high:8;    /* base 24..31 */
 123 };
 124 struct real_descriptor64 {
 125         uint32_t        limit_low16:16, /* limit 0..15 */
 126                         base_low16:16,  /* base  0..15 */
 127                         base_med8:8,    /* base  16..23 */
 128                         access8:8,      /* access byte */
 129                         limit_high4:4,  /* limit 16..19 */
 130                         granularity4:4, /* granularity */
 131                         base_high8:8,   /* base 24..31 */
 132                         base_top32:32,  /* base 32..63 */
 133                         reserved32:32;  /* reserved/zero */
 134 };
 135 struct real_gate {
 136         uint32_t        offset_low:16,  /* offset 0..15 */
 137                         selector:16,
 138                         word_count:8,
 139                         access:8,
 140                         offset_high:16; /* offset 16..31 */
 141 };
 142 struct real_gate64 {
 143         uint32_t        offset_low16:16,        /* offset 0..15 */
 144                         selector16:16,
 145                         IST:3,
 146                         zeroes5:5,
 147                         access8:8,
 148                         offset_high16:16,       /* offset 16..31 */
 149                         offset_top32:32,        /* offset 32..63 */
 150                         reserved32:32;          /* reserved/zero */
 151 };
 152
 153 /*
 154  * We build descriptors and gates in a 'fake' format to let the
 155  * fields be contiguous.  We shuffle them into the real format
 156  * at runtime.
 157  */
 158 struct fake_descriptor {
 159         uint32_t        offset:32;              /* offset */
 160         uint32_t        lim_or_seg:20;          /* limit */
 161                                                 /* or segment, for gate */
 162         uint32_t        size_or_wdct:4;         /* size/granularity */
 163                                                 /* word count, for gate */
 164         uint32_t        access:8;               /* access */
 165 };
 166 struct fake_descriptor64 {
 167         uint32_t        offset[2];              /* offset [0..31,32..63] */
 168         uint32_t        lim_or_seg:20;          /* limit */
 169                                                 /* or segment, for gate */
 170         uint32_t        size_or_IST:4;          /* size/granularity */
 171                                                 /* IST for gates */
 172         uint32_t        access:8;               /* access */
 173         uint32_t        reserved:32;            /* reserved/zero */
 174 };
 175 #define FAKE_UBER64(addr32)     { (uint32_t) (addr32), KERNEL_UBER_BASE_HI32 }
 176 #define FAKE_COMPAT(addr32)     { (uint32_t) (addr32), 0x0 }
 177 #define UBER64(addr32)          ((addr64_t) (uintptr_t)addr32 + KERNEL_UBER_BASE)
 178
 179 /*
 180  * Boot-time data for master (or only) CPU
 181  */
 182 extern struct fake_descriptor   master_idt[IDTSZ];
 183 extern struct fake_descriptor   master_gdt[GDTSZ];
 184 extern struct fake_descriptor   master_ldt[LDTSZ];
 185 extern struct i386_tss          master_ktss;
 186 extern struct sysenter_stack    master_sstk;
 187
 188 extern struct fake_descriptor64 master_idt64[IDTSZ];
 189 extern struct fake_descriptor64 kernel_ldt_desc64;
 190 extern struct fake_descriptor64 kernel_tss_desc64;
 191 extern struct x86_64_tss        master_ktss64;
 192
 193 __BEGIN_DECLS
 194
 195 extern char                     df_task_stack[];
 196 extern char                     df_task_stack_end[];
 197 extern struct i386_tss          master_dftss;
 198 extern void                     df_task_start(void);
 199
 200 extern char                     mc_task_stack[];
 201 extern char                     mc_task_stack_end[];
 202 extern struct i386_tss          master_mctss;
 203 extern void                     mc_task_start(void);
 204
 205 #if     MACH_KDB
 206 extern char                     db_stack_store[];
 207 extern char                     db_task_stack_store[];
 208 extern struct i386_tss          master_dbtss;
 209 extern void                     db_task_start(void);
 210 #endif  /* MACH_KDB */
 211
 212 __END_DECLS
 213
 214 #endif  /*__ASSEMBLER__*/
 215
 216 #define SZ_64           0x2                     /* 64-bit segment */
 217 #define SZ_32           0x4                     /* 32-bit segment */
 218 #define SZ_G            0x8                     /* 4K limit field */
 219
 220 #define ACC_A           0x01                    /* accessed */
 221 #define ACC_TYPE        0x1e                    /* type field: */
 222
 223 #define ACC_TYPE_SYSTEM 0x00                    /* system descriptors: */
 224
 225 #define ACC_LDT         0x02                        /* LDT */
 226 #define ACC_CALL_GATE_16 0x04                       /* 16-bit call gate */
 227 #define ACC_TASK_GATE   0x05                        /* task gate */
 228 #define ACC_TSS         0x09                        /* task segment */
 229 #define ACC_CALL_GATE   0x0c                        /* call gate */
 230 #define ACC_INTR_GATE   0x0e                        /* interrupt gate */
 231 #define ACC_TRAP_GATE   0x0f                        /* trap gate */
 232
 233 #define ACC_TSS_BUSY    0x02                        /* task busy */
 234
 235 #define ACC_TYPE_USER   0x10                    /* user descriptors */
 236
 237 #define ACC_DATA        0x10                        /* data */
 238 #define ACC_DATA_W      0x12                        /* data, writable */
 239 #define ACC_DATA_E      0x14                        /* data, expand-down */
 240 #define ACC_DATA_EW     0x16                        /* data, expand-down,
 241                                                              writable */
 242 #define ACC_CODE        0x18                        /* code */
 243 #define ACC_CODE_R      0x1a                        /* code, readable */
 244 #define ACC_CODE_C      0x1c                        /* code, conforming */
 245 #define ACC_CODE_CR     0x1e                        /* code, conforming,
 246                                                        readable */
 247 #define ACC_PL          0x60                    /* access rights: */
 248 #define ACC_PL_K        0x00                    /* kernel access only */
 249 #define ACC_PL_U        0x60                    /* user access */
 250 #define ACC_P           0x80                    /* segment present */
 251
 252 /*
 253  * Components of a selector
 254  */
 255 #define SEL_LDTS        0x04                    /* local selector */
 256 #define SEL_PL          0x03                    /* privilege level: */
 257 #define SEL_PL_K        0x00                        /* kernel selector */
 258 #define SEL_PL_U        0x03                        /* user selector */
 259
 260 /*
 261  * Convert selector to descriptor table index.
 262  */
 263 #define sel_idx(sel)    (selector_to_sel(sel).index)
 264 #define SEL_TO_INDEX(s) ((s)>>3)
 265
 266 #define NULL_SEG        0
 267
 268 /*
 269  * User descriptors for MACH - 32-bit flat address space
 270  */
 271 #define SYSENTER_CS     0x07            /* sysenter kernel code segment */
 272 #define SYSENTER_DS     0x0f            /* sysenter kernel data segment */
 273 #define USER_CS         0x17            /* user code segment
 274                                            Must be SYSENTER_CS+16 for sysexit */
 275 /* Special case: sysenter with EFL_TF (trace bit) set - use iret not sysexit */
 276 #define SYSENTER_TF_CS  (USER_CS|0x10000)
 277 #define USER_DS         0x1f            /* user data segment
 278                                            Must be SYSENTER_CS+24 for sysexit */
 279 #define USER64_CS       0x27            /* 64-bit user code segment
 280                                            Must be USER_CS+16 for sysret */
 281 #define USER64_DS       USER_DS         /* 64-bit user data segment == 32-bit */
 282 #define SYSCALL_CS      0x2f            /* 64-bit syscall pseudo-segment */
 283 #define USER_CTHREAD    0x37            /* user cthread area */
 284 #define USER_SETTABLE   0x3f            /* start of user settable ldt entries */
 285 #define USLDTSZ         10              /* number of user settable entries */
 286
 287 /*
 288  * Kernel descriptors for MACH - 32-bit flat address space.
 289  */
 290 #define KERNEL_CS       0x08            /* kernel code */
 291 #define KERNEL_DS       0x10            /* kernel data */
 292 #define KERNEL_LDT      0x18            /* master LDT */
 293 #define KERNEL_LDT_2    0x20            /* master LDT expanded for 64-bit */
 294 #define KERNEL_TSS      0x28            /* master TSS */
 295 #define KERNEL_TSS_2    0x30            /* master TSS expanded for 64-bit */
 296
 297 #define MC_TSS          0x38            /* machine-check handler TSS */
 298
 299 #define CPU_DATA_GS     0x48            /* per-cpu data */
 300
 301 #define DF_TSS          0x50            /* double-fault handler TSS */
 302
 303 #define USER_LDT        0x58
 304 #define USER_TSS        0x60
 305 #define FPE_CS          0x68
 306
 307 #define USER_WINDOW_SEL 0x70            /* window for copyin/copyout */
 308 #define PHYS_WINDOW_SEL 0x78            /* window for copyin/copyout */
 309
 310 #define KERNEL64_CS     0x80            /* kernel 64-bit code */
 311 #define KERNEL64_SS     0x88            /* kernel 64-bit (syscall) stack */
 312
 313 #if     MACH_KDB
 314 #define DEBUG_TSS       0x90            /* debug TSS (uniprocessor) */
 315 #endif
 316
 317 #ifndef __ASSEMBLER__
 318 struct __gdt_desc_struct {
 319   unsigned short size;
 320   unsigned long address __attribute__((packed));
 321   unsigned short pad;
 322 } __attribute__ ((packed));
 323
 324 struct __idt_desc_struct {
 325   unsigned short size;
 326   unsigned long address __attribute__((packed));
 327   unsigned short pad;
 328 } __attribute__ ((packed));
 329 #endif /* __ASSEMBLER__ */
 330
 331 #endif  /* _I386_SEG_H_ */