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 X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) 72 #define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) 73 #define X86_MODRM_RM(modrm) ((modrm) & 0x07) 74 75 #define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) 76 #define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) 77 #define X86_SIB_BASE(sib) ((sib) & 0x07) 78 79 #define X86_REX_W(rex) ((rex) & 8) 80 #define X86_REX_R(rex) ((rex) & 4) 81 #define X86_REX_X(rex) ((rex) & 2) 82 #define X86_REX_B(rex) ((rex) & 1) 83 84 /* VEX bit flags */ 85 #define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ 86 #define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ 87 #define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ 88 #define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ 89 #define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ 90 /* VEX bit fields */ 91 #define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ 92 #define X86_VEX2_M 1 /* VEX2.M always 1 */ 93 #define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ 94 #define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ 95 #define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ 96 97 /* The last prefix is needed for two-byte and three-byte opcodes */ 98 static inline insn_byte_t insn_last_prefix(struct insn *insn) 99 { 100 return insn->prefixes.bytes[3]; 101 } 102 103 extern void insn_init(struct insn *insn, const void *kaddr, int x86_64); 104 extern void insn_get_prefixes(struct insn *insn); 105 extern void insn_get_opcode(struct insn *insn); 106 extern void insn_get_modrm(struct insn *insn); 107 extern void insn_get_sib(struct insn *insn); 108 extern void insn_get_displacement(struct insn *insn); 109 extern void insn_get_immediate(struct insn *insn); 110 extern void insn_get_length(struct insn *insn); 111 112 /* Attribute will be determined after getting ModRM (for opcode groups) */ 113 static inline void insn_get_attribute(struct insn *insn) 114 { 115 insn_get_modrm(insn); 116 } 117 118 /* Instruction uses RIP-relative addressing */ 119 extern int insn_rip_relative(struct insn *insn); 120 121 /* Init insn for kernel text */ 122 static inline void kernel_insn_init(struct insn *insn, const void *kaddr) 123 { 124 #ifdef CONFIG_X86_64 125 insn_init(insn, kaddr, 1); 126 #else /* CONFIG_X86_32 */ 127 insn_init(insn, kaddr, 0); 128 #endif 129 } 130 131 static inline int insn_is_avx(struct insn *insn) 132 { 133 if (!insn->prefixes.got) 134 insn_get_prefixes(insn); 135 return (insn->vex_prefix.value != 0); 136 } 137 138 static inline insn_byte_t insn_vex_m_bits(struct insn *insn) 139 { 140 if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 141 return X86_VEX2_M; 142 else 143 return X86_VEX3_M(insn->vex_prefix.bytes[1]); 144 } 145 146 static inline insn_byte_t insn_vex_p_bits(struct insn *insn) 147 { 148 if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ 149 return X86_VEX_P(insn->vex_prefix.bytes[1]); 150 else 151 return X86_VEX_P(insn->vex_prefix.bytes[2]); 152 } 153 154 /* Offset of each field from kaddr */ 155 static inline int insn_offset_rex_prefix(struct insn *insn) 156 { 157 return insn->prefixes.nbytes; 158 } 159 static inline int insn_offset_vex_prefix(struct insn *insn) 160 { 161 return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; 162 } 163 static inline int insn_offset_opcode(struct insn *insn) 164 { 165 return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; 166 } 167 static inline int insn_offset_modrm(struct insn *insn) 168 { 169 return insn_offset_opcode(insn) + insn->opcode.nbytes; 170 } 171 static inline int insn_offset_sib(struct insn *insn) 172 { 173 return insn_offset_modrm(insn) + insn->modrm.nbytes; 174 } 175 static inline int insn_offset_displacement(struct insn *insn) 176 { 177 return insn_offset_sib(insn) + insn->sib.nbytes; 178 } 179 static inline int insn_offset_immediate(struct insn *insn) 180 { 181 return insn_offset_displacement(insn) + insn->displacement.nbytes; 182 } 183 184 #endif /* _ASM_X86_INSN_H */ 185