1d046b725SJosh Poimboeuf /* SPDX-License-Identifier: GPL-2.0-or-later */ 2d046b725SJosh Poimboeuf #ifndef _ASM_X86_INSN_H 3d046b725SJosh Poimboeuf #define _ASM_X86_INSN_H 4d046b725SJosh Poimboeuf /* 5d046b725SJosh Poimboeuf * x86 instruction analysis 6d046b725SJosh Poimboeuf * 7d046b725SJosh Poimboeuf * Copyright (C) IBM Corporation, 2009 8d046b725SJosh Poimboeuf */ 9d046b725SJosh Poimboeuf 10d046b725SJosh Poimboeuf /* insn_attr_t is defined in inat.h */ 1100a26390SJosh Poimboeuf #include "inat.h" 12d046b725SJosh Poimboeuf 13d046b725SJosh Poimboeuf struct insn_field { 14d046b725SJosh Poimboeuf union { 15d046b725SJosh Poimboeuf insn_value_t value; 16d046b725SJosh Poimboeuf insn_byte_t bytes[4]; 17d046b725SJosh Poimboeuf }; 18d046b725SJosh Poimboeuf /* !0 if we've run insn_get_xxx() for this field */ 19d046b725SJosh Poimboeuf unsigned char got; 20d046b725SJosh Poimboeuf unsigned char nbytes; 21d046b725SJosh Poimboeuf }; 22d046b725SJosh Poimboeuf 23d046b725SJosh Poimboeuf struct insn { 24d046b725SJosh Poimboeuf struct insn_field prefixes; /* 25d046b725SJosh Poimboeuf * Prefixes 26d046b725SJosh Poimboeuf * prefixes.bytes[3]: last prefix 27d046b725SJosh Poimboeuf */ 28d046b725SJosh Poimboeuf struct insn_field rex_prefix; /* REX prefix */ 29d046b725SJosh Poimboeuf struct insn_field vex_prefix; /* VEX prefix */ 30d046b725SJosh Poimboeuf struct insn_field opcode; /* 31d046b725SJosh Poimboeuf * opcode.bytes[0]: opcode1 32d046b725SJosh Poimboeuf * opcode.bytes[1]: opcode2 33d046b725SJosh Poimboeuf * opcode.bytes[2]: opcode3 34d046b725SJosh Poimboeuf */ 35d046b725SJosh Poimboeuf struct insn_field modrm; 36d046b725SJosh Poimboeuf struct insn_field sib; 37d046b725SJosh Poimboeuf struct insn_field displacement; 38d046b725SJosh Poimboeuf union { 39d046b725SJosh Poimboeuf struct insn_field immediate; 40d046b725SJosh Poimboeuf struct insn_field moffset1; /* for 64bit MOV */ 41d046b725SJosh Poimboeuf struct insn_field immediate1; /* for 64bit imm or off16/32 */ 42d046b725SJosh Poimboeuf }; 43d046b725SJosh Poimboeuf union { 44d046b725SJosh Poimboeuf struct insn_field moffset2; /* for 64bit MOV */ 45d046b725SJosh Poimboeuf struct insn_field immediate2; /* for 64bit imm or seg16 */ 46d046b725SJosh Poimboeuf }; 47d046b725SJosh Poimboeuf 484d65adfcSMasami Hiramatsu int emulate_prefix_size; 49d046b725SJosh Poimboeuf insn_attr_t attr; 50d046b725SJosh Poimboeuf unsigned char opnd_bytes; 51d046b725SJosh Poimboeuf unsigned char addr_bytes; 52d046b725SJosh Poimboeuf unsigned char length; 53d046b725SJosh Poimboeuf unsigned char x86_64; 54d046b725SJosh Poimboeuf 55d046b725SJosh Poimboeuf const insn_byte_t *kaddr; /* kernel address of insn to analyze */ 56d046b725SJosh Poimboeuf const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */ 57d046b725SJosh Poimboeuf const insn_byte_t *next_byte; 58d046b725SJosh Poimboeuf }; 59d046b725SJosh Poimboeuf 60d046b725SJosh Poimboeuf #define MAX_INSN_SIZE 15 61d046b725SJosh Poimboeuf 62d046b725SJosh Poimboeuf #define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) 63d046b725SJosh Poimboeuf #define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) 64d046b725SJosh Poimboeuf #define X86_MODRM_RM(modrm) ((modrm) & 0x07) 65d046b725SJosh Poimboeuf 66d046b725SJosh Poimboeuf #define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) 67d046b725SJosh Poimboeuf #define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) 68d046b725SJosh Poimboeuf #define X86_SIB_BASE(sib) ((sib) & 0x07) 69d046b725SJosh Poimboeuf 70d046b725SJosh Poimboeuf #define X86_REX_W(rex) ((rex) & 8) 71d046b725SJosh Poimboeuf #define X86_REX_R(rex) ((rex) & 4) 72d046b725SJosh Poimboeuf #define X86_REX_X(rex) ((rex) & 2) 73d046b725SJosh Poimboeuf #define X86_REX_B(rex) ((rex) & 1) 74d046b725SJosh Poimboeuf 75d046b725SJosh Poimboeuf /* VEX bit flags */ 76d046b725SJosh Poimboeuf #define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ 77d046b725SJosh Poimboeuf #define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ 78d046b725SJosh Poimboeuf #define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ 79d046b725SJosh Poimboeuf #define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ 80d046b725SJosh Poimboeuf #define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ 81d046b725SJosh Poimboeuf /* VEX bit fields */ 82d046b725SJosh Poimboeuf #define X86_EVEX_M(vex) ((vex) & 0x03) /* EVEX Byte1 */ 83d046b725SJosh Poimboeuf #define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ 84d046b725SJosh Poimboeuf #define X86_VEX2_M 1 /* VEX2.M always 1 */ 85d046b725SJosh Poimboeuf #define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ 86d046b725SJosh Poimboeuf #define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ 87d046b725SJosh Poimboeuf #define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ 88d046b725SJosh Poimboeuf 89d046b725SJosh Poimboeuf extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64); 90d046b725SJosh Poimboeuf extern void insn_get_prefixes(struct insn *insn); 91d046b725SJosh Poimboeuf extern void insn_get_opcode(struct insn *insn); 92d046b725SJosh Poimboeuf extern void insn_get_modrm(struct insn *insn); 93d046b725SJosh Poimboeuf extern void insn_get_sib(struct insn *insn); 94d046b725SJosh Poimboeuf extern void insn_get_displacement(struct insn *insn); 95d046b725SJosh Poimboeuf extern void insn_get_immediate(struct insn *insn); 96d046b725SJosh Poimboeuf extern void insn_get_length(struct insn *insn); 97d046b725SJosh Poimboeuf 98d046b725SJosh Poimboeuf /* Attribute will be determined after getting ModRM (for opcode groups) */ 99d046b725SJosh Poimboeuf static inline void insn_get_attribute(struct insn *insn) 100d046b725SJosh Poimboeuf { 101d046b725SJosh Poimboeuf insn_get_modrm(insn); 102d046b725SJosh Poimboeuf } 103d046b725SJosh Poimboeuf 104d046b725SJosh Poimboeuf /* Instruction uses RIP-relative addressing */ 105d046b725SJosh Poimboeuf extern int insn_rip_relative(struct insn *insn); 106d046b725SJosh Poimboeuf 107d046b725SJosh Poimboeuf /* Init insn for kernel text */ 108d046b725SJosh Poimboeuf static inline void kernel_insn_init(struct insn *insn, 109d046b725SJosh Poimboeuf const void *kaddr, int buf_len) 110d046b725SJosh Poimboeuf { 111d046b725SJosh Poimboeuf #ifdef CONFIG_X86_64 112d046b725SJosh Poimboeuf insn_init(insn, kaddr, buf_len, 1); 113d046b725SJosh Poimboeuf #else /* CONFIG_X86_32 */ 114d046b725SJosh Poimboeuf insn_init(insn, kaddr, buf_len, 0); 115d046b725SJosh Poimboeuf #endif 116d046b725SJosh Poimboeuf } 117d046b725SJosh Poimboeuf 118d046b725SJosh Poimboeuf static inline int insn_is_avx(struct insn *insn) 119d046b725SJosh Poimboeuf { 120d046b725SJosh Poimboeuf if (!insn->prefixes.got) 121d046b725SJosh Poimboeuf insn_get_prefixes(insn); 122d046b725SJosh Poimboeuf return (insn->vex_prefix.value != 0); 123d046b725SJosh Poimboeuf } 124d046b725SJosh Poimboeuf 125d046b725SJosh Poimboeuf static inline int insn_is_evex(struct insn *insn) 126d046b725SJosh Poimboeuf { 127d046b725SJosh Poimboeuf if (!insn->prefixes.got) 128d046b725SJosh Poimboeuf insn_get_prefixes(insn); 129d046b725SJosh Poimboeuf return (insn->vex_prefix.nbytes == 4); 130d046b725SJosh Poimboeuf } 131d046b725SJosh Poimboeuf 1324d65adfcSMasami Hiramatsu static inline int insn_has_emulate_prefix(struct insn *insn) 1334d65adfcSMasami Hiramatsu { 1344d65adfcSMasami Hiramatsu return !!insn->emulate_prefix_size; 1354d65adfcSMasami Hiramatsu } 1364d65adfcSMasami Hiramatsu 137d046b725SJosh Poimboeuf /* Ensure this instruction is decoded completely */ 138d046b725SJosh Poimboeuf static inline int insn_complete(struct insn *insn) 139d046b725SJosh Poimboeuf { 140d046b725SJosh Poimboeuf return insn->opcode.got && insn->modrm.got && insn->sib.got && 141d046b725SJosh Poimboeuf insn->displacement.got && insn->immediate.got; 142d046b725SJosh Poimboeuf } 143d046b725SJosh Poimboeuf 144d046b725SJosh Poimboeuf static inline insn_byte_t insn_vex_m_bits(struct insn *insn) 145d046b725SJosh Poimboeuf { 146d046b725SJosh Poimboeuf if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 147d046b725SJosh Poimboeuf return X86_VEX2_M; 148d046b725SJosh Poimboeuf else if (insn->vex_prefix.nbytes == 3) /* 3 bytes VEX */ 149d046b725SJosh Poimboeuf return X86_VEX3_M(insn->vex_prefix.bytes[1]); 150d046b725SJosh Poimboeuf else /* EVEX */ 151d046b725SJosh Poimboeuf return X86_EVEX_M(insn->vex_prefix.bytes[1]); 152d046b725SJosh Poimboeuf } 153d046b725SJosh Poimboeuf 154d046b725SJosh Poimboeuf static inline insn_byte_t insn_vex_p_bits(struct insn *insn) 155d046b725SJosh Poimboeuf { 156d046b725SJosh Poimboeuf if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 157d046b725SJosh Poimboeuf return X86_VEX_P(insn->vex_prefix.bytes[1]); 158d046b725SJosh Poimboeuf else 159d046b725SJosh Poimboeuf return X86_VEX_P(insn->vex_prefix.bytes[2]); 160d046b725SJosh Poimboeuf } 161d046b725SJosh Poimboeuf 162d046b725SJosh Poimboeuf /* Get the last prefix id from last prefix or VEX prefix */ 163d046b725SJosh Poimboeuf static inline int insn_last_prefix_id(struct insn *insn) 164d046b725SJosh Poimboeuf { 165d046b725SJosh Poimboeuf if (insn_is_avx(insn)) 166d046b725SJosh Poimboeuf return insn_vex_p_bits(insn); /* VEX_p is a SIMD prefix id */ 167d046b725SJosh Poimboeuf 168d046b725SJosh Poimboeuf if (insn->prefixes.bytes[3]) 169d046b725SJosh Poimboeuf return inat_get_last_prefix_id(insn->prefixes.bytes[3]); 170d046b725SJosh Poimboeuf 171d046b725SJosh Poimboeuf return 0; 172d046b725SJosh Poimboeuf } 173d046b725SJosh Poimboeuf 174d046b725SJosh Poimboeuf /* Offset of each field from kaddr */ 175d046b725SJosh Poimboeuf static inline int insn_offset_rex_prefix(struct insn *insn) 176d046b725SJosh Poimboeuf { 177d046b725SJosh Poimboeuf return insn->prefixes.nbytes; 178d046b725SJosh Poimboeuf } 179d046b725SJosh Poimboeuf static inline int insn_offset_vex_prefix(struct insn *insn) 180d046b725SJosh Poimboeuf { 181d046b725SJosh Poimboeuf return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; 182d046b725SJosh Poimboeuf } 183d046b725SJosh Poimboeuf static inline int insn_offset_opcode(struct insn *insn) 184d046b725SJosh Poimboeuf { 185d046b725SJosh Poimboeuf return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; 186d046b725SJosh Poimboeuf } 187d046b725SJosh Poimboeuf static inline int insn_offset_modrm(struct insn *insn) 188d046b725SJosh Poimboeuf { 189d046b725SJosh Poimboeuf return insn_offset_opcode(insn) + insn->opcode.nbytes; 190d046b725SJosh Poimboeuf } 191d046b725SJosh Poimboeuf static inline int insn_offset_sib(struct insn *insn) 192d046b725SJosh Poimboeuf { 193d046b725SJosh Poimboeuf return insn_offset_modrm(insn) + insn->modrm.nbytes; 194d046b725SJosh Poimboeuf } 195d046b725SJosh Poimboeuf static inline int insn_offset_displacement(struct insn *insn) 196d046b725SJosh Poimboeuf { 197d046b725SJosh Poimboeuf return insn_offset_sib(insn) + insn->sib.nbytes; 198d046b725SJosh Poimboeuf } 199d046b725SJosh Poimboeuf static inline int insn_offset_immediate(struct insn *insn) 200d046b725SJosh Poimboeuf { 201d046b725SJosh Poimboeuf return insn_offset_displacement(insn) + insn->displacement.nbytes; 202d046b725SJosh Poimboeuf } 203d046b725SJosh Poimboeuf 204d046b725SJosh Poimboeuf #define POP_SS_OPCODE 0x1f 205d046b725SJosh Poimboeuf #define MOV_SREG_OPCODE 0x8e 206d046b725SJosh Poimboeuf 207d046b725SJosh Poimboeuf /* 208d046b725SJosh Poimboeuf * Intel SDM Vol.3A 6.8.3 states; 209d046b725SJosh Poimboeuf * "Any single-step trap that would be delivered following the MOV to SS 210d046b725SJosh Poimboeuf * instruction or POP to SS instruction (because EFLAGS.TF is 1) is 211d046b725SJosh Poimboeuf * suppressed." 212d046b725SJosh Poimboeuf * This function returns true if @insn is MOV SS or POP SS. On these 213d046b725SJosh Poimboeuf * instructions, single stepping is suppressed. 214d046b725SJosh Poimboeuf */ 215d046b725SJosh Poimboeuf static inline int insn_masking_exception(struct insn *insn) 216d046b725SJosh Poimboeuf { 217d046b725SJosh Poimboeuf return insn->opcode.bytes[0] == POP_SS_OPCODE || 218d046b725SJosh Poimboeuf (insn->opcode.bytes[0] == MOV_SREG_OPCODE && 219d046b725SJosh Poimboeuf X86_MODRM_REG(insn->modrm.bytes[0]) == 2); 220d046b725SJosh Poimboeuf } 221d046b725SJosh Poimboeuf 222d046b725SJosh Poimboeuf #endif /* _ASM_X86_INSN_H */ 223