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 #ifndef __ASSEMBLY__ 12 13 #include <linux/types.h> 14 15 /* 8 byte segment descriptor */ 16 struct desc_struct { 17 u16 limit0; 18 u16 base0; 19 u16 base1: 8, type: 4, s: 1, dpl: 2, p: 1; 20 u16 limit1: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8; 21 } __attribute__((packed)); 22 23 #define GDT_ENTRY_INIT(flags, base, limit) \ 24 { \ 25 .limit0 = (u16) (limit), \ 26 .limit1 = ((limit) >> 16) & 0x0F, \ 27 .base0 = (u16) (base), \ 28 .base1 = ((base) >> 16) & 0xFF, \ 29 .base2 = ((base) >> 24) & 0xFF, \ 30 .type = (flags & 0x0f), \ 31 .s = (flags >> 4) & 0x01, \ 32 .dpl = (flags >> 5) & 0x03, \ 33 .p = (flags >> 7) & 0x01, \ 34 .avl = (flags >> 12) & 0x01, \ 35 .l = (flags >> 13) & 0x01, \ 36 .d = (flags >> 14) & 0x01, \ 37 .g = (flags >> 15) & 0x01, \ 38 } 39 40 enum { 41 GATE_INTERRUPT = 0xE, 42 GATE_TRAP = 0xF, 43 GATE_CALL = 0xC, 44 GATE_TASK = 0x5, 45 }; 46 47 enum { 48 DESC_TSS = 0x9, 49 DESC_LDT = 0x2, 50 DESCTYPE_S = 0x10, /* !system */ 51 }; 52 53 /* LDT or TSS descriptor in the GDT. */ 54 struct ldttss_desc { 55 u16 limit0; 56 u16 base0; 57 58 u16 base1 : 8, type : 5, dpl : 2, p : 1; 59 u16 limit1 : 4, zero0 : 3, g : 1, base2 : 8; 60 #ifdef CONFIG_X86_64 61 u32 base3; 62 u32 zero1; 63 #endif 64 } __attribute__((packed)); 65 66 typedef struct ldttss_desc ldt_desc; 67 typedef struct ldttss_desc tss_desc; 68 69 struct idt_bits { 70 u16 ist : 3, 71 zero : 5, 72 type : 5, 73 dpl : 2, 74 p : 1; 75 } __attribute__((packed)); 76 77 struct gate_struct { 78 u16 offset_low; 79 u16 segment; 80 struct idt_bits bits; 81 u16 offset_middle; 82 #ifdef CONFIG_X86_64 83 u32 offset_high; 84 u32 reserved; 85 #endif 86 } __attribute__((packed)); 87 88 typedef struct gate_struct gate_desc; 89 90 static inline unsigned long gate_offset(const gate_desc *g) 91 { 92 #ifdef CONFIG_X86_64 93 return g->offset_low | ((unsigned long)g->offset_middle << 16) | 94 ((unsigned long) g->offset_high << 32); 95 #else 96 return g->offset_low | ((unsigned long)g->offset_middle << 16); 97 #endif 98 } 99 100 static inline unsigned long gate_segment(const gate_desc *g) 101 { 102 return g->segment; 103 } 104 105 struct desc_ptr { 106 unsigned short size; 107 unsigned long address; 108 } __attribute__((packed)) ; 109 110 #endif /* !__ASSEMBLY__ */ 111 112 /* Access rights as returned by LAR */ 113 #define AR_TYPE_RODATA (0 * (1 << 9)) 114 #define AR_TYPE_RWDATA (1 * (1 << 9)) 115 #define AR_TYPE_RODATA_EXPDOWN (2 * (1 << 9)) 116 #define AR_TYPE_RWDATA_EXPDOWN (3 * (1 << 9)) 117 #define AR_TYPE_XOCODE (4 * (1 << 9)) 118 #define AR_TYPE_XRCODE (5 * (1 << 9)) 119 #define AR_TYPE_XOCODE_CONF (6 * (1 << 9)) 120 #define AR_TYPE_XRCODE_CONF (7 * (1 << 9)) 121 #define AR_TYPE_MASK (7 * (1 << 9)) 122 123 #define AR_DPL0 (0 * (1 << 13)) 124 #define AR_DPL3 (3 * (1 << 13)) 125 #define AR_DPL_MASK (3 * (1 << 13)) 126 127 #define AR_A (1 << 8) /* "Accessed" */ 128 #define AR_S (1 << 12) /* If clear, "System" segment */ 129 #define AR_P (1 << 15) /* "Present" */ 130 #define AR_AVL (1 << 20) /* "AVaiLable" (no HW effect) */ 131 #define AR_L (1 << 21) /* "Long mode" for code segments */ 132 #define AR_DB (1 << 22) /* D/B, effect depends on type */ 133 #define AR_G (1 << 23) /* "Granularity" (limit in pages) */ 134 135 #endif /* _ASM_X86_DESC_DEFS_H */ 136