1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Written 2000 by Andi Kleen */ 3 #ifndef _ASM_X86_DESC_DEFS_H 4 #define _ASM_X86_DESC_DEFS_H 5 6 /* 7 * Segment descriptor structure definitions, usable from both x86_64 and i386 8 * archs. 9 */ 10 11 /* 12 * Low-level interface mapping flags/field names to bits 13 */ 14 15 /* Flags for _DESC_S (non-system) descriptors */ 16 #define _DESC_ACCESSED 0x0001 17 #define _DESC_DATA_WRITABLE 0x0002 18 #define _DESC_CODE_READABLE 0x0002 19 #define _DESC_DATA_EXPAND_DOWN 0x0004 20 #define _DESC_CODE_CONFORMING 0x0004 21 #define _DESC_CODE_EXECUTABLE 0x0008 22 23 /* Common flags */ 24 #define _DESC_S 0x0010 25 #define _DESC_DPL(dpl) ((dpl) << 5) 26 #define _DESC_PRESENT 0x0080 27 28 #define _DESC_LONG_CODE 0x2000 29 #define _DESC_DB 0x4000 30 #define _DESC_GRANULARITY_4K 0x8000 31 32 /* System descriptors have a numeric "type" field instead of flags */ 33 #define _DESC_SYSTEM(code) (code) 34 35 /* 36 * High-level interface mapping intended usage to low-level combinations 37 * of flags 38 */ 39 40 #define _DESC_DATA (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \ 41 _DESC_DATA_WRITABLE) 42 #define _DESC_CODE (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \ 43 _DESC_CODE_READABLE | _DESC_CODE_EXECUTABLE) 44 45 #define DESC_DATA16 (_DESC_DATA) 46 #define DESC_CODE16 (_DESC_CODE) 47 48 #define DESC_DATA32 (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB) 49 #define DESC_DATA32_BIOS (_DESC_DATA | _DESC_DB) 50 51 #define DESC_CODE32 (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_DB) 52 #define DESC_CODE32_BIOS (_DESC_CODE | _DESC_DB) 53 54 #define DESC_TSS32 (_DESC_SYSTEM(9) | _DESC_PRESENT) 55 56 #define DESC_DATA64 (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB) 57 #define DESC_CODE64 (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_LONG_CODE) 58 59 #define DESC_USER (_DESC_DPL(3)) 60 61 #ifndef __ASSEMBLY__ 62 63 #include <linux/types.h> 64 65 /* 8 byte segment descriptor */ 66 struct desc_struct { 67 u16 limit0; 68 u16 base0; 69 u16 base1: 8, type: 4, s: 1, dpl: 2, p: 1; 70 u16 limit1: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8; 71 } __attribute__((packed)); 72 73 #define GDT_ENTRY_INIT(flags, base, limit) \ 74 { \ 75 .limit0 = ((limit) >> 0) & 0xFFFF, \ 76 .limit1 = ((limit) >> 16) & 0x000F, \ 77 .base0 = ((base) >> 0) & 0xFFFF, \ 78 .base1 = ((base) >> 16) & 0x00FF, \ 79 .base2 = ((base) >> 24) & 0x00FF, \ 80 .type = ((flags) >> 0) & 0x000F, \ 81 .s = ((flags) >> 4) & 0x0001, \ 82 .dpl = ((flags) >> 5) & 0x0003, \ 83 .p = ((flags) >> 7) & 0x0001, \ 84 .avl = ((flags) >> 12) & 0x0001, \ 85 .l = ((flags) >> 13) & 0x0001, \ 86 .d = ((flags) >> 14) & 0x0001, \ 87 .g = ((flags) >> 15) & 0x0001, \ 88 } 89 90 enum { 91 GATE_INTERRUPT = 0xE, 92 GATE_TRAP = 0xF, 93 GATE_CALL = 0xC, 94 GATE_TASK = 0x5, 95 }; 96 97 enum { 98 DESC_TSS = 0x9, 99 DESC_LDT = 0x2, 100 DESCTYPE_S = 0x10, /* !system */ 101 }; 102 103 /* LDT or TSS descriptor in the GDT. */ 104 struct ldttss_desc { 105 u16 limit0; 106 u16 base0; 107 108 u16 base1 : 8, type : 5, dpl : 2, p : 1; 109 u16 limit1 : 4, zero0 : 3, g : 1, base2 : 8; 110 #ifdef CONFIG_X86_64 111 u32 base3; 112 u32 zero1; 113 #endif 114 } __attribute__((packed)); 115 116 typedef struct ldttss_desc ldt_desc; 117 typedef struct ldttss_desc tss_desc; 118 119 struct idt_bits { 120 u16 ist : 3, 121 zero : 5, 122 type : 5, 123 dpl : 2, 124 p : 1; 125 } __attribute__((packed)); 126 127 struct idt_data { 128 unsigned int vector; 129 unsigned int segment; 130 struct idt_bits bits; 131 const void *addr; 132 }; 133 134 struct gate_struct { 135 u16 offset_low; 136 u16 segment; 137 struct idt_bits bits; 138 u16 offset_middle; 139 #ifdef CONFIG_X86_64 140 u32 offset_high; 141 u32 reserved; 142 #endif 143 } __attribute__((packed)); 144 145 typedef struct gate_struct gate_desc; 146 147 #ifndef _SETUP 148 static inline unsigned long gate_offset(const gate_desc *g) 149 { 150 #ifdef CONFIG_X86_64 151 return g->offset_low | ((unsigned long)g->offset_middle << 16) | 152 ((unsigned long) g->offset_high << 32); 153 #else 154 return g->offset_low | ((unsigned long)g->offset_middle << 16); 155 #endif 156 } 157 158 static inline unsigned long gate_segment(const gate_desc *g) 159 { 160 return g->segment; 161 } 162 #endif 163 164 struct desc_ptr { 165 unsigned short size; 166 unsigned long address; 167 } __attribute__((packed)) ; 168 169 #endif /* !__ASSEMBLY__ */ 170 171 /* Boot IDT definitions */ 172 #define BOOT_IDT_ENTRIES 32 173 174 /* Access rights as returned by LAR */ 175 #define AR_TYPE_RODATA (0 * (1 << 9)) 176 #define AR_TYPE_RWDATA (1 * (1 << 9)) 177 #define AR_TYPE_RODATA_EXPDOWN (2 * (1 << 9)) 178 #define AR_TYPE_RWDATA_EXPDOWN (3 * (1 << 9)) 179 #define AR_TYPE_XOCODE (4 * (1 << 9)) 180 #define AR_TYPE_XRCODE (5 * (1 << 9)) 181 #define AR_TYPE_XOCODE_CONF (6 * (1 << 9)) 182 #define AR_TYPE_XRCODE_CONF (7 * (1 << 9)) 183 #define AR_TYPE_MASK (7 * (1 << 9)) 184 185 #define AR_DPL0 (0 * (1 << 13)) 186 #define AR_DPL3 (3 * (1 << 13)) 187 #define AR_DPL_MASK (3 * (1 << 13)) 188 189 #define AR_A (1 << 8) /* "Accessed" */ 190 #define AR_S (1 << 12) /* If clear, "System" segment */ 191 #define AR_P (1 << 15) /* "Present" */ 192 #define AR_AVL (1 << 20) /* "AVaiLable" (no HW effect) */ 193 #define AR_L (1 << 21) /* "Long mode" for code segments */ 194 #define AR_DB (1 << 22) /* D/B, effect depends on type */ 195 #define AR_G (1 << 23) /* "Granularity" (limit in pages) */ 196 197 #endif /* _ASM_X86_DESC_DEFS_H */ 198