1#ifndef _ASM_X86_SEGMENT_H_ 2#define _ASM_X86_SEGMENT_H_ 3 4/* Simple and small GDT entries for booting only */ 5 6#define GDT_ENTRY_BOOT_CS 2 7#define __BOOT_CS (GDT_ENTRY_BOOT_CS * 8) 8 9#define GDT_ENTRY_BOOT_DS (GDT_ENTRY_BOOT_CS + 1) 10#define __BOOT_DS (GDT_ENTRY_BOOT_DS * 8) 11 12#define GDT_ENTRY_BOOT_TSS (GDT_ENTRY_BOOT_CS + 2) 13#define __BOOT_TSS (GDT_ENTRY_BOOT_TSS * 8) 14 15#ifdef CONFIG_X86_32 16/* 17 * The layout of the per-CPU GDT under Linux: 18 * 19 * 0 - null 20 * 1 - reserved 21 * 2 - reserved 22 * 3 - reserved 23 * 24 * 4 - unused <==== new cacheline 25 * 5 - unused 26 * 27 * ------- start of TLS (Thread-Local Storage) segments: 28 * 29 * 6 - TLS segment #1 [ glibc's TLS segment ] 30 * 7 - TLS segment #2 [ Wine's %fs Win32 segment ] 31 * 8 - TLS segment #3 32 * 9 - reserved 33 * 10 - reserved 34 * 11 - reserved 35 * 36 * ------- start of kernel segments: 37 * 38 * 12 - kernel code segment <==== new cacheline 39 * 13 - kernel data segment 40 * 14 - default user CS 41 * 15 - default user DS 42 * 16 - TSS 43 * 17 - LDT 44 * 18 - PNPBIOS support (16->32 gate) 45 * 19 - PNPBIOS support 46 * 20 - PNPBIOS support 47 * 21 - PNPBIOS support 48 * 22 - PNPBIOS support 49 * 23 - APM BIOS support 50 * 24 - APM BIOS support 51 * 25 - APM BIOS support 52 * 53 * 26 - ESPFIX small SS 54 * 27 - per-cpu [ offset to per-cpu data area ] 55 * 28 - unused 56 * 29 - unused 57 * 30 - unused 58 * 31 - TSS for double fault handler 59 */ 60#define GDT_ENTRY_TLS_MIN 6 61#define GDT_ENTRY_TLS_MAX (GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1) 62 63#define GDT_ENTRY_DEFAULT_USER_CS 14 64#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS * 8 + 3) 65 66#define GDT_ENTRY_DEFAULT_USER_DS 15 67#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS * 8 + 3) 68 69#define GDT_ENTRY_KERNEL_BASE 12 70 71#define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE + 0) 72#define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8) 73 74#define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE + 1) 75#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8) 76 77#define GDT_ENTRY_TSS (GDT_ENTRY_KERNEL_BASE + 4) 78#define GDT_ENTRY_LDT (GDT_ENTRY_KERNEL_BASE + 5) 79 80#define GDT_ENTRY_PNPBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 6) 81#define GDT_ENTRY_APMBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 11) 82 83#define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE + 14) 84#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8) 85 86#define GDT_ENTRY_PERCPU (GDT_ENTRY_KERNEL_BASE + 15) 87#ifdef CONFIG_SMP 88#define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8) 89#else 90#define __KERNEL_PERCPU 0 91#endif 92 93#define GDT_ENTRY_DOUBLEFAULT_TSS 31 94 95/* 96 * The GDT has 32 entries 97 */ 98#define GDT_ENTRIES 32 99 100/* The PnP BIOS entries in the GDT */ 101#define GDT_ENTRY_PNPBIOS_CS32 (GDT_ENTRY_PNPBIOS_BASE + 0) 102#define GDT_ENTRY_PNPBIOS_CS16 (GDT_ENTRY_PNPBIOS_BASE + 1) 103#define GDT_ENTRY_PNPBIOS_DS (GDT_ENTRY_PNPBIOS_BASE + 2) 104#define GDT_ENTRY_PNPBIOS_TS1 (GDT_ENTRY_PNPBIOS_BASE + 3) 105#define GDT_ENTRY_PNPBIOS_TS2 (GDT_ENTRY_PNPBIOS_BASE + 4) 106 107/* The PnP BIOS selectors */ 108#define PNP_CS32 (GDT_ENTRY_PNPBIOS_CS32 * 8) /* segment for calling fn */ 109#define PNP_CS16 (GDT_ENTRY_PNPBIOS_CS16 * 8) /* code segment for BIOS */ 110#define PNP_DS (GDT_ENTRY_PNPBIOS_DS * 8) /* data segment for BIOS */ 111#define PNP_TS1 (GDT_ENTRY_PNPBIOS_TS1 * 8) /* transfer data segment */ 112#define PNP_TS2 (GDT_ENTRY_PNPBIOS_TS2 * 8) /* another data segment */ 113 114/* Bottom two bits of selector give the ring privilege level */ 115#define SEGMENT_RPL_MASK 0x3 116/* Bit 2 is table indicator (LDT/GDT) */ 117#define SEGMENT_TI_MASK 0x4 118 119/* User mode is privilege level 3 */ 120#define USER_RPL 0x3 121/* LDT segment has TI set, GDT has it cleared */ 122#define SEGMENT_LDT 0x4 123#define SEGMENT_GDT 0x0 124 125/* 126 * Matching rules for certain types of segments. 127 */ 128 129/* Matches only __KERNEL_CS, ignoring PnP / USER / APM segments */ 130#define SEGMENT_IS_KERNEL_CODE(x) (((x) & 0xfc) == GDT_ENTRY_KERNEL_CS * 8) 131 132/* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */ 133#define SEGMENT_IS_FLAT_CODE(x) (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8) 134 135/* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */ 136#define SEGMENT_IS_PNP_CODE(x) (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8) 137 138 139#else 140#include <asm/cache.h> 141 142#define __KERNEL_CS 0x10 143#define __KERNEL_DS 0x18 144 145#define __KERNEL32_CS 0x08 146 147/* 148 * we cannot use the same code segment descriptor for user and kernel 149 * -- not even in the long flat mode, because of different DPL /kkeil 150 * The segment offset needs to contain a RPL. Grr. -AK 151 * GDT layout to get 64bit syscall right (sysret hardcodes gdt offsets) 152 */ 153 154#define __USER32_CS 0x23 /* 4*8+3 */ 155#define __USER_DS 0x2b /* 5*8+3 */ 156#define __USER_CS 0x33 /* 6*8+3 */ 157#define __USER32_DS __USER_DS 158 159#define GDT_ENTRY_TSS 8 /* needs two entries */ 160#define GDT_ENTRY_LDT 10 /* needs two entries */ 161#define GDT_ENTRY_TLS_MIN 12 162#define GDT_ENTRY_TLS_MAX 14 163 164#define GDT_ENTRY_PER_CPU 15 /* Abused to load per CPU data from limit */ 165#define __PER_CPU_SEG (GDT_ENTRY_PER_CPU * 8 + 3) 166 167/* TLS indexes for 64bit - hardcoded in arch_prctl */ 168#define FS_TLS 0 169#define GS_TLS 1 170 171#define GS_TLS_SEL ((GDT_ENTRY_TLS_MIN+GS_TLS)*8 + 3) 172#define FS_TLS_SEL ((GDT_ENTRY_TLS_MIN+FS_TLS)*8 + 3) 173 174#define GDT_ENTRIES 16 175 176#endif 177 178#ifndef CONFIG_PARAVIRT 179#define get_kernel_rpl() 0 180#endif 181 182/* User mode is privilege level 3 */ 183#define USER_RPL 0x3 184/* LDT segment has TI set, GDT has it cleared */ 185#define SEGMENT_LDT 0x4 186#define SEGMENT_GDT 0x0 187 188/* Bottom two bits of selector give the ring privilege level */ 189#define SEGMENT_RPL_MASK 0x3 190/* Bit 2 is table indicator (LDT/GDT) */ 191#define SEGMENT_TI_MASK 0x4 192 193#define IDT_ENTRIES 256 194#define GDT_SIZE (GDT_ENTRIES * 8) 195#define GDT_ENTRY_TLS_ENTRIES 3 196#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8) 197 198#ifdef __KERNEL__ 199#ifndef __ASSEMBLY__ 200extern const char early_idt_handlers[IDT_ENTRIES][10]; 201#endif 202#endif 203 204#endif 205