1#ifndef _ASM_X86_SEGMENT_H 2#define _ASM_X86_SEGMENT_H 3 4/* Constructor for a conventional segment GDT (or LDT) entry */ 5/* This is a macro so it can be used in initializers */ 6#define GDT_ENTRY(flags, base, limit) \ 7 ((((base) & 0xff000000ULL) << (56-24)) | \ 8 (((flags) & 0x0000f0ffULL) << 40) | \ 9 (((limit) & 0x000f0000ULL) << (48-16)) | \ 10 (((base) & 0x00ffffffULL) << 16) | \ 11 (((limit) & 0x0000ffffULL))) 12 13/* Simple and small GDT entries for booting only */ 14 15#define GDT_ENTRY_BOOT_CS 2 16#define __BOOT_CS (GDT_ENTRY_BOOT_CS * 8) 17 18#define GDT_ENTRY_BOOT_DS (GDT_ENTRY_BOOT_CS + 1) 19#define __BOOT_DS (GDT_ENTRY_BOOT_DS * 8) 20 21#define GDT_ENTRY_BOOT_TSS (GDT_ENTRY_BOOT_CS + 2) 22#define __BOOT_TSS (GDT_ENTRY_BOOT_TSS * 8) 23 24#ifdef CONFIG_X86_32 25/* 26 * The layout of the per-CPU GDT under Linux: 27 * 28 * 0 - null 29 * 1 - reserved 30 * 2 - reserved 31 * 3 - reserved 32 * 33 * 4 - unused <==== new cacheline 34 * 5 - unused 35 * 36 * ------- start of TLS (Thread-Local Storage) segments: 37 * 38 * 6 - TLS segment #1 [ glibc's TLS segment ] 39 * 7 - TLS segment #2 [ Wine's %fs Win32 segment ] 40 * 8 - TLS segment #3 41 * 9 - reserved 42 * 10 - reserved 43 * 11 - reserved 44 * 45 * ------- start of kernel segments: 46 * 47 * 12 - kernel code segment <==== new cacheline 48 * 13 - kernel data segment 49 * 14 - default user CS 50 * 15 - default user DS 51 * 16 - TSS 52 * 17 - LDT 53 * 18 - PNPBIOS support (16->32 gate) 54 * 19 - PNPBIOS support 55 * 20 - PNPBIOS support 56 * 21 - PNPBIOS support 57 * 22 - PNPBIOS support 58 * 23 - APM BIOS support 59 * 24 - APM BIOS support 60 * 25 - APM BIOS support 61 * 62 * 26 - ESPFIX small SS 63 * 27 - per-cpu [ offset to per-cpu data area ] 64 * 28 - stack_canary-20 [ for stack protector ] 65 * 29 - unused 66 * 30 - unused 67 * 31 - TSS for double fault handler 68 */ 69#define GDT_ENTRY_TLS_MIN 6 70#define GDT_ENTRY_TLS_MAX (GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1) 71 72#define GDT_ENTRY_DEFAULT_USER_CS 14 73 74#define GDT_ENTRY_DEFAULT_USER_DS 15 75 76#define GDT_ENTRY_KERNEL_BASE 12 77 78#define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE + 0) 79 80#define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE + 1) 81 82#define GDT_ENTRY_TSS (GDT_ENTRY_KERNEL_BASE + 4) 83#define GDT_ENTRY_LDT (GDT_ENTRY_KERNEL_BASE + 5) 84 85#define GDT_ENTRY_PNPBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 6) 86#define GDT_ENTRY_APMBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 11) 87 88#define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE + 14) 89#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8) 90 91#define GDT_ENTRY_PERCPU (GDT_ENTRY_KERNEL_BASE + 15) 92#ifdef CONFIG_SMP 93#define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8) 94#else 95#define __KERNEL_PERCPU 0 96#endif 97 98#define GDT_ENTRY_STACK_CANARY (GDT_ENTRY_KERNEL_BASE + 16) 99#ifdef CONFIG_CC_STACKPROTECTOR 100#define __KERNEL_STACK_CANARY (GDT_ENTRY_STACK_CANARY * 8) 101#else 102#define __KERNEL_STACK_CANARY 0 103#endif 104 105#define GDT_ENTRY_DOUBLEFAULT_TSS 31 106 107/* 108 * The GDT has 32 entries 109 */ 110#define GDT_ENTRIES 32 111 112/* The PnP BIOS entries in the GDT */ 113#define GDT_ENTRY_PNPBIOS_CS32 (GDT_ENTRY_PNPBIOS_BASE + 0) 114#define GDT_ENTRY_PNPBIOS_CS16 (GDT_ENTRY_PNPBIOS_BASE + 1) 115#define GDT_ENTRY_PNPBIOS_DS (GDT_ENTRY_PNPBIOS_BASE + 2) 116#define GDT_ENTRY_PNPBIOS_TS1 (GDT_ENTRY_PNPBIOS_BASE + 3) 117#define GDT_ENTRY_PNPBIOS_TS2 (GDT_ENTRY_PNPBIOS_BASE + 4) 118 119/* The PnP BIOS selectors */ 120#define PNP_CS32 (GDT_ENTRY_PNPBIOS_CS32 * 8) /* segment for calling fn */ 121#define PNP_CS16 (GDT_ENTRY_PNPBIOS_CS16 * 8) /* code segment for BIOS */ 122#define PNP_DS (GDT_ENTRY_PNPBIOS_DS * 8) /* data segment for BIOS */ 123#define PNP_TS1 (GDT_ENTRY_PNPBIOS_TS1 * 8) /* transfer data segment */ 124#define PNP_TS2 (GDT_ENTRY_PNPBIOS_TS2 * 8) /* another data segment */ 125 126/* Bottom two bits of selector give the ring privilege level */ 127#define SEGMENT_RPL_MASK 0x3 128/* Bit 2 is table indicator (LDT/GDT) */ 129#define SEGMENT_TI_MASK 0x4 130 131/* User mode is privilege level 3 */ 132#define USER_RPL 0x3 133/* LDT segment has TI set, GDT has it cleared */ 134#define SEGMENT_LDT 0x4 135#define SEGMENT_GDT 0x0 136 137/* 138 * Matching rules for certain types of segments. 139 */ 140 141/* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */ 142#define SEGMENT_IS_PNP_CODE(x) (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8) 143 144 145#else 146#include <asm/cache.h> 147 148#define GDT_ENTRY_KERNEL32_CS 1 149#define GDT_ENTRY_KERNEL_CS 2 150#define GDT_ENTRY_KERNEL_DS 3 151 152#define __KERNEL32_CS (GDT_ENTRY_KERNEL32_CS * 8) 153 154/* 155 * we cannot use the same code segment descriptor for user and kernel 156 * -- not even in the long flat mode, because of different DPL /kkeil 157 * The segment offset needs to contain a RPL. Grr. -AK 158 * GDT layout to get 64bit syscall right (sysret hardcodes gdt offsets) 159 */ 160#define GDT_ENTRY_DEFAULT_USER32_CS 4 161#define GDT_ENTRY_DEFAULT_USER_DS 5 162#define GDT_ENTRY_DEFAULT_USER_CS 6 163#define __USER32_CS (GDT_ENTRY_DEFAULT_USER32_CS * 8 + 3) 164#define __USER32_DS __USER_DS 165 166#define GDT_ENTRY_TSS 8 /* needs two entries */ 167#define GDT_ENTRY_LDT 10 /* needs two entries */ 168#define GDT_ENTRY_TLS_MIN 12 169#define GDT_ENTRY_TLS_MAX 14 170 171#define GDT_ENTRY_PER_CPU 15 /* Abused to load per CPU data from limit */ 172#define __PER_CPU_SEG (GDT_ENTRY_PER_CPU * 8 + 3) 173 174/* TLS indexes for 64bit - hardcoded in arch_prctl */ 175#define FS_TLS 0 176#define GS_TLS 1 177 178#define GS_TLS_SEL ((GDT_ENTRY_TLS_MIN+GS_TLS)*8 + 3) 179#define FS_TLS_SEL ((GDT_ENTRY_TLS_MIN+FS_TLS)*8 + 3) 180 181#define GDT_ENTRIES 16 182 183#endif 184 185#define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8) 186#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8) 187#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS* 8 + 3) 188#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS* 8 + 3) 189#ifndef CONFIG_PARAVIRT 190#define get_kernel_rpl() 0 191#endif 192 193/* User mode is privilege level 3 */ 194#define USER_RPL 0x3 195/* LDT segment has TI set, GDT has it cleared */ 196#define SEGMENT_LDT 0x4 197#define SEGMENT_GDT 0x0 198 199/* Bottom two bits of selector give the ring privilege level */ 200#define SEGMENT_RPL_MASK 0x3 201/* Bit 2 is table indicator (LDT/GDT) */ 202#define SEGMENT_TI_MASK 0x4 203 204#define IDT_ENTRIES 256 205#define NUM_EXCEPTION_VECTORS 32 206#define GDT_SIZE (GDT_ENTRIES * 8) 207#define GDT_ENTRY_TLS_ENTRIES 3 208#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8) 209 210#ifdef __KERNEL__ 211#ifndef __ASSEMBLY__ 212extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][10]; 213#endif 214#endif 215 216#endif /* _ASM_X86_SEGMENT_H */ 217