1 #ifndef _ASM_X86_INSN_H 2 #define _ASM_X86_INSN_H 3 /* 4 * x86 instruction analysis 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 * 20 * Copyright (C) IBM Corporation, 2009 21 */ 22 23 /* insn_attr_t is defined in inat.h */ 24 #include <asm/inat.h> 25 26 struct insn_field { 27 union { 28 insn_value_t value; 29 insn_byte_t bytes[4]; 30 }; 31 /* !0 if we've run insn_get_xxx() for this field */ 32 unsigned char got; 33 unsigned char nbytes; 34 }; 35 36 struct insn { 37 struct insn_field prefixes; /* 38 * Prefixes 39 * prefixes.bytes[3]: last prefix 40 */ 41 struct insn_field rex_prefix; /* REX prefix */ 42 struct insn_field vex_prefix; /* VEX prefix */ 43 struct insn_field opcode; /* 44 * opcode.bytes[0]: opcode1 45 * opcode.bytes[1]: opcode2 46 * opcode.bytes[2]: opcode3 47 */ 48 struct insn_field modrm; 49 struct insn_field sib; 50 struct insn_field displacement; 51 union { 52 struct insn_field immediate; 53 struct insn_field moffset1; /* for 64bit MOV */ 54 struct insn_field immediate1; /* for 64bit imm or off16/32 */ 55 }; 56 union { 57 struct insn_field moffset2; /* for 64bit MOV */ 58 struct insn_field immediate2; /* for 64bit imm or seg16 */ 59 }; 60 61 insn_attr_t attr; 62 unsigned char opnd_bytes; 63 unsigned char addr_bytes; 64 unsigned char length; 65 unsigned char x86_64; 66 67 const insn_byte_t *kaddr; /* kernel address of insn to analyze */ 68 const insn_byte_t *next_byte; 69 }; 70 71 #define MAX_INSN_SIZE 16 72 73 #define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) 74 #define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) 75 #define X86_MODRM_RM(modrm) ((modrm) & 0x07) 76 77 #define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) 78 #define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) 79 #define X86_SIB_BASE(sib) ((sib) & 0x07) 80 81 #define X86_REX_W(rex) ((rex) & 8) 82 #define X86_REX_R(rex) ((rex) & 4) 83 #define X86_REX_X(rex) ((rex) & 2) 84 #define X86_REX_B(rex) ((rex) & 1) 85 86 /* VEX bit flags */ 87 #define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ 88 #define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ 89 #define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ 90 #define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ 91 #define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ 92 /* VEX bit fields */ 93 #define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ 94 #define X86_VEX2_M 1 /* VEX2.M always 1 */ 95 #define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ 96 #define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ 97 #define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ 98 99 /* The last prefix is needed for two-byte and three-byte opcodes */ 100 static inline insn_byte_t insn_last_prefix(struct insn *insn) 101 { 102 return insn->prefixes.bytes[3]; 103 } 104 105 extern void insn_init(struct insn *insn, const void *kaddr, int x86_64); 106 extern void insn_get_prefixes(struct insn *insn); 107 extern void insn_get_opcode(struct insn *insn); 108 extern void insn_get_modrm(struct insn *insn); 109 extern void insn_get_sib(struct insn *insn); 110 extern void insn_get_displacement(struct insn *insn); 111 extern void insn_get_immediate(struct insn *insn); 112 extern void insn_get_length(struct insn *insn); 113 114 /* Attribute will be determined after getting ModRM (for opcode groups) */ 115 static inline void insn_get_attribute(struct insn *insn) 116 { 117 insn_get_modrm(insn); 118 } 119 120 /* Instruction uses RIP-relative addressing */ 121 extern int insn_rip_relative(struct insn *insn); 122 123 /* Init insn for kernel text */ 124 static inline void kernel_insn_init(struct insn *insn, const void *kaddr) 125 { 126 #ifdef CONFIG_X86_64 127 insn_init(insn, kaddr, 1); 128 #else /* CONFIG_X86_32 */ 129 insn_init(insn, kaddr, 0); 130 #endif 131 } 132 133 static inline int insn_is_avx(struct insn *insn) 134 { 135 if (!insn->prefixes.got) 136 insn_get_prefixes(insn); 137 return (insn->vex_prefix.value != 0); 138 } 139 140 static inline insn_byte_t insn_vex_m_bits(struct insn *insn) 141 { 142 if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 143 return X86_VEX2_M; 144 else 145 return X86_VEX3_M(insn->vex_prefix.bytes[1]); 146 } 147 148 static inline insn_byte_t insn_vex_p_bits(struct insn *insn) 149 { 150 if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 151 return X86_VEX_P(insn->vex_prefix.bytes[1]); 152 else 153 return X86_VEX_P(insn->vex_prefix.bytes[2]); 154 } 155 156 /* Offset of each field from kaddr */ 157 static inline int insn_offset_rex_prefix(struct insn *insn) 158 { 159 return insn->prefixes.nbytes; 160 } 161 static inline int insn_offset_vex_prefix(struct insn *insn) 162 { 163 return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; 164 } 165 static inline int insn_offset_opcode(struct insn *insn) 166 { 167 return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; 168 } 169 static inline int insn_offset_modrm(struct insn *insn) 170 { 171 return insn_offset_opcode(insn) + insn->opcode.nbytes; 172 } 173 static inline int insn_offset_sib(struct insn *insn) 174 { 175 return insn_offset_modrm(insn) + insn->modrm.nbytes; 176 } 177 static inline int insn_offset_displacement(struct insn *insn) 178 { 179 return insn_offset_sib(insn) + insn->sib.nbytes; 180 } 181 static inline int insn_offset_immediate(struct insn *insn) 182 { 183 return insn_offset_displacement(insn) + insn->displacement.nbytes; 184 } 185 186 #endif /* _ASM_X86_INSN_H */ 187