| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| #ifndef _ASM_X86_INSN_H |
| #define _ASM_X86_INSN_H |
| /* |
| * x86 instruction analysis |
| * |
| * Copyright (C) IBM Corporation, 2009 |
| */ |
| |
| /* insn_attr_t is defined in inat.h */ |
| #include <asm/inat.h> |
| |
| struct insn_field { |
| union { |
| insn_value_t value; |
| insn_byte_t bytes[4]; |
| }; |
| /* !0 if we've run insn_get_xxx() for this field */ |
| unsigned char got; |
| unsigned char nbytes; |
| }; |
| |
| struct insn { |
| struct insn_field prefixes; /* |
| * Prefixes |
| * prefixes.bytes[3]: last prefix |
| */ |
| struct insn_field rex_prefix; /* REX prefix */ |
| struct insn_field vex_prefix; /* VEX prefix */ |
| struct insn_field opcode; /* |
| * opcode.bytes[0]: opcode1 |
| * opcode.bytes[1]: opcode2 |
| * opcode.bytes[2]: opcode3 |
| */ |
| struct insn_field modrm; |
| struct insn_field sib; |
| struct insn_field displacement; |
| union { |
| struct insn_field immediate; |
| struct insn_field moffset1; /* for 64bit MOV */ |
| struct insn_field immediate1; /* for 64bit imm or off16/32 */ |
| }; |
| union { |
| struct insn_field moffset2; /* for 64bit MOV */ |
| struct insn_field immediate2; /* for 64bit imm or seg16 */ |
| }; |
| |
| int emulate_prefix_size; |
| insn_attr_t attr; |
| unsigned char opnd_bytes; |
| unsigned char addr_bytes; |
| unsigned char length; |
| unsigned char x86_64; |
| |
| const insn_byte_t *kaddr; /* kernel address of insn to analyze */ |
| const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */ |
| const insn_byte_t *next_byte; |
| }; |
| |
| #define MAX_INSN_SIZE 15 |
| |
| #define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) |
| #define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) |
| #define X86_MODRM_RM(modrm) ((modrm) & 0x07) |
| |
| #define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) |
| #define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) |
| #define X86_SIB_BASE(sib) ((sib) & 0x07) |
| |
| #define X86_REX_W(rex) ((rex) & 8) |
| #define X86_REX_R(rex) ((rex) & 4) |
| #define X86_REX_X(rex) ((rex) & 2) |
| #define X86_REX_B(rex) ((rex) & 1) |
| |
| /* VEX bit flags */ |
| #define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ |
| #define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ |
| #define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ |
| #define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ |
| #define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ |
| /* VEX bit fields */ |
| #define X86_EVEX_M(vex) ((vex) & 0x03) /* EVEX Byte1 */ |
| #define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ |
| #define X86_VEX2_M 1 /* VEX2.M always 1 */ |
| #define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ |
| #define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ |
| #define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ |
| |
| extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64); |
| extern void insn_get_prefixes(struct insn *insn); |
| extern void insn_get_opcode(struct insn *insn); |
| extern void insn_get_modrm(struct insn *insn); |
| extern void insn_get_sib(struct insn *insn); |
| extern void insn_get_displacement(struct insn *insn); |
| extern void insn_get_immediate(struct insn *insn); |
| extern void insn_get_length(struct insn *insn); |
| |
| /* Attribute will be determined after getting ModRM (for opcode groups) */ |
| static inline void insn_get_attribute(struct insn *insn) |
| { |
| insn_get_modrm(insn); |
| } |
| |
| /* Instruction uses RIP-relative addressing */ |
| extern int insn_rip_relative(struct insn *insn); |
| |
| /* Init insn for kernel text */ |
| static inline void kernel_insn_init(struct insn *insn, |
| const void *kaddr, int buf_len) |
| { |
| #ifdef CONFIG_X86_64 |
| insn_init(insn, kaddr, buf_len, 1); |
| #else /* CONFIG_X86_32 */ |
| insn_init(insn, kaddr, buf_len, 0); |
| #endif |
| } |
| |
| static inline int insn_is_avx(struct insn *insn) |
| { |
| if (!insn->prefixes.got) |
| insn_get_prefixes(insn); |
| return (insn->vex_prefix.value != 0); |
| } |
| |
| static inline int insn_is_evex(struct insn *insn) |
| { |
| if (!insn->prefixes.got) |
| insn_get_prefixes(insn); |
| return (insn->vex_prefix.nbytes == 4); |
| } |
| |
| static inline int insn_has_emulate_prefix(struct insn *insn) |
| { |
| return !!insn->emulate_prefix_size; |
| } |
| |
| /* Ensure this instruction is decoded completely */ |
| static inline int insn_complete(struct insn *insn) |
| { |
| return insn->opcode.got && insn->modrm.got && insn->sib.got && |
| insn->displacement.got && insn->immediate.got; |
| } |
| |
| static inline insn_byte_t insn_vex_m_bits(struct insn *insn) |
| { |
| if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ |
| return X86_VEX2_M; |
| else if (insn->vex_prefix.nbytes == 3) /* 3 bytes VEX */ |
| return X86_VEX3_M(insn->vex_prefix.bytes[1]); |
| else /* EVEX */ |
| return X86_EVEX_M(insn->vex_prefix.bytes[1]); |
| } |
| |
| static inline insn_byte_t insn_vex_p_bits(struct insn *insn) |
| { |
| if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ |
| return X86_VEX_P(insn->vex_prefix.bytes[1]); |
| else |
| return X86_VEX_P(insn->vex_prefix.bytes[2]); |
| } |
| |
| /* Get the last prefix id from last prefix or VEX prefix */ |
| static inline int insn_last_prefix_id(struct insn *insn) |
| { |
| if (insn_is_avx(insn)) |
| return insn_vex_p_bits(insn); /* VEX_p is a SIMD prefix id */ |
| |
| if (insn->prefixes.bytes[3]) |
| return inat_get_last_prefix_id(insn->prefixes.bytes[3]); |
| |
| return 0; |
| } |
| |
| /* Offset of each field from kaddr */ |
| static inline int insn_offset_rex_prefix(struct insn *insn) |
| { |
| return insn->prefixes.nbytes; |
| } |
| static inline int insn_offset_vex_prefix(struct insn *insn) |
| { |
| return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; |
| } |
| static inline int insn_offset_opcode(struct insn *insn) |
| { |
| return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; |
| } |
| static inline int insn_offset_modrm(struct insn *insn) |
| { |
| return insn_offset_opcode(insn) + insn->opcode.nbytes; |
| } |
| static inline int insn_offset_sib(struct insn *insn) |
| { |
| return insn_offset_modrm(insn) + insn->modrm.nbytes; |
| } |
| static inline int insn_offset_displacement(struct insn *insn) |
| { |
| return insn_offset_sib(insn) + insn->sib.nbytes; |
| } |
| static inline int insn_offset_immediate(struct insn *insn) |
| { |
| return insn_offset_displacement(insn) + insn->displacement.nbytes; |
| } |
| |
| #define POP_SS_OPCODE 0x1f |
| #define MOV_SREG_OPCODE 0x8e |
| |
| /* |
| * Intel SDM Vol.3A 6.8.3 states; |
| * "Any single-step trap that would be delivered following the MOV to SS |
| * instruction or POP to SS instruction (because EFLAGS.TF is 1) is |
| * suppressed." |
| * This function returns true if @insn is MOV SS or POP SS. On these |
| * instructions, single stepping is suppressed. |
| */ |
| static inline int insn_masking_exception(struct insn *insn) |
| { |
| return insn->opcode.bytes[0] == POP_SS_OPCODE || |
| (insn->opcode.bytes[0] == MOV_SREG_OPCODE && |
| X86_MODRM_REG(insn->modrm.bytes[0]) == 2); |
| } |
| |
| #endif /* _ASM_X86_INSN_H */ |
