osfmk/i386/seg.h

   1 /*
   2  * Copyright (c) 2000-2012 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 #ifndef __ASSEMBLER__
  59 #include <stdint.h>
  60 #include <mach/vm_types.h>
  61 #include <architecture/i386/sel.h>
  62
  63 /*
  64  * i386 segmentation.
  65  */
  66
  67 static inline uint16_t
  68 sel_to_selector(sel_t   sel)
  69 {
  70     union {
  71         sel_t           sel;
  72         uint16_t        selector;
  73     } tconv;
  74
  75     tconv.sel = sel;
  76
  77     return (tconv.selector);
  78 }
  79
  80 static inline sel_t
  81 selector_to_sel(uint16_t selector)
  82 {
  83     union {
  84         uint16_t        selector;
  85         sel_t           sel;
  86     } tconv;
  87
  88     tconv.selector = selector;
  89
  90     return (tconv.sel);
  91 }
  92
  93 #define LDTSZ           8192            /* size of the kernel ldt in entries */
  94 #define LDTSZ_MIN       SEL_TO_INDEX(USER_SETTABLE)
  95                                         /* kernel ldt entries */
  96
  97 #define GDTSZ           19
  98
  99 /*
 100  * Interrupt table is always 256 entries long.
 101  */
 102 #define IDTSZ           256
 103
 104 #include <sys/cdefs.h>
 105
 106 /*
 107  * Real segment descriptor.
 108  */
 109 struct real_descriptor {
 110         uint32_t        limit_low:16,   /* limit 0..15 */
 111                         base_low:16,    /* base  0..15 */
 112                         base_med:8,     /* base  16..23 */
 113                         access:8,       /* access byte */
 114                         limit_high:4,   /* limit 16..19 */
 115                         granularity:4,  /* granularity */
 116                         base_high:8;    /* base 24..31 */
 117 };
 118 struct real_descriptor64 {
 119         uint32_t        limit_low16:16, /* limit 0..15 */
 120                         base_low16:16,  /* base  0..15 */
 121                         base_med8:8,    /* base  16..23 */
 122                         access8:8,      /* access byte */
 123                         limit_high4:4,  /* limit 16..19 */
 124                         granularity4:4, /* granularity */
 125                         base_high8:8,   /* base 24..31 */
 126                         base_top32:32,  /* base 32..63 */
 127                         reserved32:32;  /* reserved/zero */
 128 };
 129 struct real_gate {
 130         uint32_t        offset_low:16,  /* offset 0..15 */
 131                         selector:16,
 132                         word_count:8,
 133                         access:8,
 134                         offset_high:16; /* offset 16..31 */
 135 };
 136 struct real_gate64 {
 137         uint32_t        offset_low16:16,        /* offset 0..15 */
 138                         selector16:16,
 139                         IST:3,
 140                         zeroes5:5,
 141                         access8:8,
 142                         offset_high16:16,       /* offset 16..31 */
 143                         offset_top32:32,        /* offset 32..63 */
 144                         reserved32:32;          /* reserved/zero */
 145 };
 146
 147 #define MAKE_REAL_DESCRIPTOR(base,lim,gran,acc) { \
 148         .limit_low = lim & 0xffff, \
 149         .limit_high = (lim >> 16) & 0xf, \
 150         .base_low = base & 0xffff, \
 151         .base_med = (base >> 16) & 0xff, \
 152         .base_high = (base >> 24) & 0xff, \
 153         .access = acc, \
 154         .granularity = gran \
 155 }
 156
 157 /*
 158  * We build descriptors and gates in a 'fake' format to let the
 159  * fields be contiguous.  We shuffle them into the real format
 160  * at runtime.
 161  */
 162 struct fake_descriptor {
 163         uint32_t        offset:32;              /* offset */
 164         uint32_t        lim_or_seg:20;          /* limit */
 165                                                 /* or segment, for gate */
 166         uint32_t        size_or_wdct:4;         /* size/granularity */
 167                                                 /* word count, for gate */
 168         uint32_t        access:8;               /* access */
 169 };
 170 struct fake_descriptor64 {
 171         uint64_t        offset64;               /* offset [0..31,32..63] */
 172         uint32_t        lim_or_seg:20;          /* limit */
 173                                                 /* or segment, for gate */
 174         uint32_t        size_or_IST:4;          /* size/granularity */
 175                                                 /* IST for gates */
 176         uint32_t        access:8;               /* access */
 177         uint32_t        reserved:32;            /* reserved/zero */
 178 };
 179
 180 /*
 181  * Boot-time data for master (or only) CPU
 182  */
 183 extern struct fake_descriptor   master_idt[IDTSZ];
 184 extern struct real_descriptor   master_gdt[GDTSZ];
 185 extern struct real_descriptor   master_ldt[LDTSZ];
 186 extern struct i386_tss          master_ktss;
 187 extern struct sysenter_stack    master_sstk;
 188
 189 extern struct fake_descriptor64 master_idt64[IDTSZ];
 190 extern struct x86_64_tss        master_ktss64;
 191
 192 __BEGIN_DECLS
 193
 194 extern char                     df_task_stack[];
 195 extern char                     df_task_stack_end[];
 196 extern struct i386_tss          master_dftss;
 197 extern void                     df_task_start(void);
 198
 199 extern char                     mc_task_stack[];
 200 extern char                     mc_task_stack_end[];
 201 extern struct i386_tss          master_mctss;
 202 extern void                     mc_task_start(void);
 203
 204 __END_DECLS
 205
 206 #endif  /*__ASSEMBLER__*/
 207
 208 #define SZ_64           0x2                     /* 64-bit segment */
 209 #define SZ_32           0x4                     /* 32-bit segment */
 210 #define SZ_G            0x8                     /* 4K limit field */
 211
 212 #define ACC_A           0x01                    /* accessed */
 213 #define ACC_TYPE        0x1e                    /* type field: */
 214
 215 #define ACC_TYPE_SYSTEM 0x00                    /* system descriptors: */
 216
 217 #define ACC_LDT         0x02                        /* LDT */
 218 #define ACC_CALL_GATE_16 0x04                       /* 16-bit call gate */
 219 #define ACC_TASK_GATE   0x05                        /* task gate */
 220 #define ACC_TSS         0x09                        /* task segment */
 221 #define ACC_CALL_GATE   0x0c                        /* call gate */
 222 #define ACC_INTR_GATE   0x0e                        /* interrupt gate */
 223 #define ACC_TRAP_GATE   0x0f                        /* trap gate */
 224
 225 #define ACC_TSS_BUSY    0x02                        /* task busy */
 226
 227 #define ACC_TYPE_USER   0x10                    /* user descriptors */
 228
 229 #define ACC_DATA        0x10                        /* data */
 230 #define ACC_DATA_W      0x12                        /* data, writable */
 231 #define ACC_DATA_E      0x14                        /* data, expand-down */
 232 #define ACC_DATA_EW     0x16                        /* data, expand-down,
 233                                                              writable */
 234 #define ACC_CODE        0x18                        /* code */
 235 #define ACC_CODE_R      0x1a                        /* code, readable */
 236 #define ACC_CODE_C      0x1c                        /* code, conforming */
 237 #define ACC_CODE_CR     0x1e                        /* code, conforming,
 238                                                        readable */
 239 #define ACC_PL          0x60                    /* access rights: */
 240 #define ACC_PL_K        0x00                    /* kernel access only */
 241 #define ACC_PL_U        0x60                    /* user access */
 242 #define ACC_P           0x80                    /* segment present */
 243
 244 /*
 245  * Components of a selector
 246  */
 247 #define SEL_LDTS        0x04                    /* local selector */
 248 #define SEL_PL          0x03                    /* privilege level: */
 249 #define SEL_PL_K        0x00                        /* kernel selector */
 250 #define SEL_PL_U        0x03                        /* user selector */
 251
 252 /*
 253  * Convert selector to descriptor table index.
 254  */
 255 #define sel_idx(sel)    (selector_to_sel(sel).index)
 256 #define SEL_TO_INDEX(s) ((s)>>3)
 257
 258 #define NULL_SEG        0
 259
 260
 261 /*
 262  * Kernel descriptors for MACH - 64-bit flat address space.
 263  */
 264 #define KERNEL64_CS     0x08            /* 1:  K64 code */
 265 #define SYSENTER_CS     0x0b            /*     U32 sysenter pseudo-segment */
 266 #define KERNEL64_SS     0x10            /* 2:  KERNEL64_CS+8 for syscall */
 267 #define USER_CS         0x1b            /* 3:  U32 code */
 268 #define USER_DS         0x23            /* 4:  USER_CS+8 for sysret */
 269 #define USER64_CS       0x2b            /* 5:  USER_CS+16 for sysret */
 270 #define USER64_DS       USER_DS         /*     U64 data pseudo-segment */
 271 #define KERNEL_LDT      0x30            /* 6:  */
 272                                         /* 7:  other 8 bytes of KERNEL_LDT */
 273 #define KERNEL_TSS      0x40            /* 8:  */
 274                                         /* 9:  other 8 bytes of KERNEL_TSS */
 275 #define KERNEL32_CS     0x50            /* 10: */
 276 #define USER_LDT        0x58            /* 11: */
 277                                         /* 12: other 8 bytes of USER_LDT */
 278 #define KERNEL_DS       0x68            /* 13: 32-bit kernel data */
 279
 280
 281 #define SYSENTER_TF_CS  (USER_CS|0x10000)
 282 #define SYSENTER_DS     KERNEL64_SS     /* sysenter kernel data segment */
 283
 284 #ifdef __x86_64__
 285 /*
 286  * 64-bit kernel LDT descriptors
 287  */
 288 #define SYSCALL_CS      0x07            /* syscall pseudo-segment */
 289 #define USER_CTHREAD    0x0f            /* user cthread area */
 290 #define USER_SETTABLE   0x1f            /* start of user settable ldt entries */
 291 #endif
 292
 293 #endif  /* _I386_SEG_H_ */