| 1 | /****************************************************************************** |
| 2 | * x86_emulate.c |
| 3 | * |
| 4 | * Generic x86 (32-bit and 64-bit) instruction decoder and emulator. |
| 5 | * |
| 6 | * Copyright (c) 2005 Keir Fraser |
| 7 | * |
| 8 | * Linux coding style, mod r/m decoder, segment base fixes, real-mode |
| 9 | * privileged instructions: |
| 10 | * |
| 11 | * Copyright (C) 2006 Qumranet |
| 12 | * |
| 13 | * Avi Kivity <avi@qumranet.com> |
| 14 | * Yaniv Kamay <yaniv@qumranet.com> |
| 15 | * |
| 16 | * This work is licensed under the terms of the GNU GPL, version 2. See |
| 17 | * the COPYING file in the top-level directory. |
| 18 | * |
| 19 | * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4 |
| 20 | */ |
| 21 | |
| 22 | #ifndef __KERNEL__ |
| 23 | #include <stdio.h> |
| 24 | #include <stdint.h> |
| 25 | #include <public/xen.h> |
| 26 | #define DPRINTF(_f, _a ...) printf(_f , ## _a) |
| 27 | #else |
| 28 | #include <linux/kvm_host.h> |
| 29 | #include "kvm_cache_regs.h" |
| 30 | #define DPRINTF(x...) do {} while (0) |
| 31 | #endif |
| 32 | #include <linux/module.h> |
| 33 | #include <asm/kvm_x86_emulate.h> |
| 34 | |
| 35 | /* |
| 36 | * Opcode effective-address decode tables. |
| 37 | * Note that we only emulate instructions that have at least one memory |
| 38 | * operand (excluding implicit stack references). We assume that stack |
| 39 | * references and instruction fetches will never occur in special memory |
| 40 | * areas that require emulation. So, for example, 'mov <imm>,<reg>' need |
| 41 | * not be handled. |
| 42 | */ |
| 43 | |
| 44 | /* Operand sizes: 8-bit operands or specified/overridden size. */ |
| 45 | #define ByteOp (1<<0) /* 8-bit operands. */ |
| 46 | /* Destination operand type. */ |
| 47 | #define ImplicitOps (1<<1) /* Implicit in opcode. No generic decode. */ |
| 48 | #define DstReg (2<<1) /* Register operand. */ |
| 49 | #define DstMem (3<<1) /* Memory operand. */ |
| 50 | #define DstAcc (4<<1) /* Destination Accumulator */ |
| 51 | #define DstMask (7<<1) |
| 52 | /* Source operand type. */ |
| 53 | #define SrcNone (0<<4) /* No source operand. */ |
| 54 | #define SrcImplicit (0<<4) /* Source operand is implicit in the opcode. */ |
| 55 | #define SrcReg (1<<4) /* Register operand. */ |
| 56 | #define SrcMem (2<<4) /* Memory operand. */ |
| 57 | #define SrcMem16 (3<<4) /* Memory operand (16-bit). */ |
| 58 | #define SrcMem32 (4<<4) /* Memory operand (32-bit). */ |
| 59 | #define SrcImm (5<<4) /* Immediate operand. */ |
| 60 | #define SrcImmByte (6<<4) /* 8-bit sign-extended immediate operand. */ |
| 61 | #define SrcOne (7<<4) /* Implied '1' */ |
| 62 | #define SrcMask (7<<4) |
| 63 | /* Generic ModRM decode. */ |
| 64 | #define ModRM (1<<7) |
| 65 | /* Destination is only written; never read. */ |
| 66 | #define Mov (1<<8) |
| 67 | #define BitOp (1<<9) |
| 68 | #define MemAbs (1<<10) /* Memory operand is absolute displacement */ |
| 69 | #define String (1<<12) /* String instruction (rep capable) */ |
| 70 | #define Stack (1<<13) /* Stack instruction (push/pop) */ |
| 71 | #define Group (1<<14) /* Bits 3:5 of modrm byte extend opcode */ |
| 72 | #define GroupDual (1<<15) /* Alternate decoding of mod == 3 */ |
| 73 | #define GroupMask 0xff /* Group number stored in bits 0:7 */ |
| 74 | /* Source 2 operand type */ |
| 75 | #define Src2None (0<<29) |
| 76 | #define Src2CL (1<<29) |
| 77 | #define Src2ImmByte (2<<29) |
| 78 | #define Src2One (3<<29) |
| 79 | #define Src2Imm16 (4<<29) |
| 80 | #define Src2Mask (7<<29) |
| 81 | |
| 82 | enum { |
| 83 | Group1_80, Group1_81, Group1_82, Group1_83, |
| 84 | Group1A, Group3_Byte, Group3, Group4, Group5, Group7, |
| 85 | }; |
| 86 | |
| 87 | static u32 opcode_table[256] = { |
| 88 | /* 0x00 - 0x07 */ |
| 89 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 90 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 91 | ByteOp | DstAcc | SrcImm, DstAcc | SrcImm, 0, 0, |
| 92 | /* 0x08 - 0x0F */ |
| 93 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 94 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 95 | 0, 0, 0, 0, |
| 96 | /* 0x10 - 0x17 */ |
| 97 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 98 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 99 | 0, 0, 0, 0, |
| 100 | /* 0x18 - 0x1F */ |
| 101 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 102 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 103 | 0, 0, 0, 0, |
| 104 | /* 0x20 - 0x27 */ |
| 105 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 106 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 107 | DstAcc | SrcImmByte, DstAcc | SrcImm, 0, 0, |
| 108 | /* 0x28 - 0x2F */ |
| 109 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 110 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 111 | 0, 0, 0, 0, |
| 112 | /* 0x30 - 0x37 */ |
| 113 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 114 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 115 | 0, 0, 0, 0, |
| 116 | /* 0x38 - 0x3F */ |
| 117 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 118 | ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, |
| 119 | ByteOp | DstAcc | SrcImm, DstAcc | SrcImm, |
| 120 | 0, 0, |
| 121 | /* 0x40 - 0x47 */ |
| 122 | DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, |
| 123 | /* 0x48 - 0x4F */ |
| 124 | DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, |
| 125 | /* 0x50 - 0x57 */ |
| 126 | SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, |
| 127 | SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, |
| 128 | /* 0x58 - 0x5F */ |
| 129 | DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack, |
| 130 | DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack, |
| 131 | /* 0x60 - 0x67 */ |
| 132 | 0, 0, 0, DstReg | SrcMem32 | ModRM | Mov /* movsxd (x86/64) */ , |
| 133 | 0, 0, 0, 0, |
| 134 | /* 0x68 - 0x6F */ |
| 135 | SrcImm | Mov | Stack, 0, SrcImmByte | Mov | Stack, 0, |
| 136 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* insb, insw/insd */ |
| 137 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* outsb, outsw/outsd */ |
| 138 | /* 0x70 - 0x77 */ |
| 139 | SrcImmByte, SrcImmByte, SrcImmByte, SrcImmByte, |
| 140 | SrcImmByte, SrcImmByte, SrcImmByte, SrcImmByte, |
| 141 | /* 0x78 - 0x7F */ |
| 142 | SrcImmByte, SrcImmByte, SrcImmByte, SrcImmByte, |
| 143 | SrcImmByte, SrcImmByte, SrcImmByte, SrcImmByte, |
| 144 | /* 0x80 - 0x87 */ |
| 145 | Group | Group1_80, Group | Group1_81, |
| 146 | Group | Group1_82, Group | Group1_83, |
| 147 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 148 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, |
| 149 | /* 0x88 - 0x8F */ |
| 150 | ByteOp | DstMem | SrcReg | ModRM | Mov, DstMem | SrcReg | ModRM | Mov, |
| 151 | ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 152 | DstMem | SrcReg | ModRM | Mov, ModRM | DstReg, |
| 153 | DstReg | SrcMem | ModRM | Mov, Group | Group1A, |
| 154 | /* 0x90 - 0x97 */ |
| 155 | DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, |
| 156 | /* 0x98 - 0x9F */ |
| 157 | 0, 0, SrcImm | Src2Imm16, 0, |
| 158 | ImplicitOps | Stack, ImplicitOps | Stack, 0, 0, |
| 159 | /* 0xA0 - 0xA7 */ |
| 160 | ByteOp | DstReg | SrcMem | Mov | MemAbs, DstReg | SrcMem | Mov | MemAbs, |
| 161 | ByteOp | DstMem | SrcReg | Mov | MemAbs, DstMem | SrcReg | Mov | MemAbs, |
| 162 | ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String, |
| 163 | ByteOp | ImplicitOps | String, ImplicitOps | String, |
| 164 | /* 0xA8 - 0xAF */ |
| 165 | 0, 0, ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String, |
| 166 | ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String, |
| 167 | ByteOp | ImplicitOps | String, ImplicitOps | String, |
| 168 | /* 0xB0 - 0xB7 */ |
| 169 | ByteOp | DstReg | SrcImm | Mov, ByteOp | DstReg | SrcImm | Mov, |
| 170 | ByteOp | DstReg | SrcImm | Mov, ByteOp | DstReg | SrcImm | Mov, |
| 171 | ByteOp | DstReg | SrcImm | Mov, ByteOp | DstReg | SrcImm | Mov, |
| 172 | ByteOp | DstReg | SrcImm | Mov, ByteOp | DstReg | SrcImm | Mov, |
| 173 | /* 0xB8 - 0xBF */ |
| 174 | DstReg | SrcImm | Mov, DstReg | SrcImm | Mov, |
| 175 | DstReg | SrcImm | Mov, DstReg | SrcImm | Mov, |
| 176 | DstReg | SrcImm | Mov, DstReg | SrcImm | Mov, |
| 177 | DstReg | SrcImm | Mov, DstReg | SrcImm | Mov, |
| 178 | /* 0xC0 - 0xC7 */ |
| 179 | ByteOp | DstMem | SrcImm | ModRM, DstMem | SrcImmByte | ModRM, |
| 180 | 0, ImplicitOps | Stack, 0, 0, |
| 181 | ByteOp | DstMem | SrcImm | ModRM | Mov, DstMem | SrcImm | ModRM | Mov, |
| 182 | /* 0xC8 - 0xCF */ |
| 183 | 0, 0, 0, ImplicitOps | Stack, 0, 0, 0, 0, |
| 184 | /* 0xD0 - 0xD7 */ |
| 185 | ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM, |
| 186 | ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM, |
| 187 | 0, 0, 0, 0, |
| 188 | /* 0xD8 - 0xDF */ |
| 189 | 0, 0, 0, 0, 0, 0, 0, 0, |
| 190 | /* 0xE0 - 0xE7 */ |
| 191 | 0, 0, 0, 0, |
| 192 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, |
| 193 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, |
| 194 | /* 0xE8 - 0xEF */ |
| 195 | SrcImm | Stack, SrcImm | ImplicitOps, |
| 196 | SrcImm | Src2Imm16, SrcImmByte | ImplicitOps, |
| 197 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, |
| 198 | SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, |
| 199 | /* 0xF0 - 0xF7 */ |
| 200 | 0, 0, 0, 0, |
| 201 | ImplicitOps, ImplicitOps, Group | Group3_Byte, Group | Group3, |
| 202 | /* 0xF8 - 0xFF */ |
| 203 | ImplicitOps, 0, ImplicitOps, ImplicitOps, |
| 204 | ImplicitOps, ImplicitOps, Group | Group4, Group | Group5, |
| 205 | }; |
| 206 | |
| 207 | static u32 twobyte_table[256] = { |
| 208 | /* 0x00 - 0x0F */ |
| 209 | 0, Group | GroupDual | Group7, 0, 0, 0, 0, ImplicitOps, 0, |
| 210 | ImplicitOps, ImplicitOps, 0, 0, 0, ImplicitOps | ModRM, 0, 0, |
| 211 | /* 0x10 - 0x1F */ |
| 212 | 0, 0, 0, 0, 0, 0, 0, 0, ImplicitOps | ModRM, 0, 0, 0, 0, 0, 0, 0, |
| 213 | /* 0x20 - 0x2F */ |
| 214 | ModRM | ImplicitOps, ModRM, ModRM | ImplicitOps, ModRM, 0, 0, 0, 0, |
| 215 | 0, 0, 0, 0, 0, 0, 0, 0, |
| 216 | /* 0x30 - 0x3F */ |
| 217 | ImplicitOps, 0, ImplicitOps, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 218 | /* 0x40 - 0x47 */ |
| 219 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 220 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 221 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 222 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 223 | /* 0x48 - 0x4F */ |
| 224 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 225 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 226 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 227 | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov, |
| 228 | /* 0x50 - 0x5F */ |
| 229 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 230 | /* 0x60 - 0x6F */ |
| 231 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 232 | /* 0x70 - 0x7F */ |
| 233 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 234 | /* 0x80 - 0x8F */ |
| 235 | SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, |
| 236 | SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, SrcImm, |
| 237 | /* 0x90 - 0x9F */ |
| 238 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 239 | /* 0xA0 - 0xA7 */ |
| 240 | 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, |
| 241 | DstMem | SrcReg | Src2ImmByte | ModRM, |
| 242 | DstMem | SrcReg | Src2CL | ModRM, 0, 0, |
| 243 | /* 0xA8 - 0xAF */ |
| 244 | 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, |
| 245 | DstMem | SrcReg | Src2ImmByte | ModRM, |
| 246 | DstMem | SrcReg | Src2CL | ModRM, |
| 247 | ModRM, 0, |
| 248 | /* 0xB0 - 0xB7 */ |
| 249 | ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, 0, |
| 250 | DstMem | SrcReg | ModRM | BitOp, |
| 251 | 0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov, |
| 252 | DstReg | SrcMem16 | ModRM | Mov, |
| 253 | /* 0xB8 - 0xBF */ |
| 254 | 0, 0, DstMem | SrcImmByte | ModRM, DstMem | SrcReg | ModRM | BitOp, |
| 255 | 0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov, |
| 256 | DstReg | SrcMem16 | ModRM | Mov, |
| 257 | /* 0xC0 - 0xCF */ |
| 258 | 0, 0, 0, DstMem | SrcReg | ModRM | Mov, 0, 0, 0, ImplicitOps | ModRM, |
| 259 | 0, 0, 0, 0, 0, 0, 0, 0, |
| 260 | /* 0xD0 - 0xDF */ |
| 261 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 262 | /* 0xE0 - 0xEF */ |
| 263 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 264 | /* 0xF0 - 0xFF */ |
| 265 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 |
| 266 | }; |
| 267 | |
| 268 | static u32 group_table[] = { |
| 269 | [Group1_80*8] = |
| 270 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 271 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 272 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 273 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 274 | [Group1_81*8] = |
| 275 | DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM, |
| 276 | DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM, |
| 277 | DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM, |
| 278 | DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM, |
| 279 | [Group1_82*8] = |
| 280 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 281 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 282 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 283 | ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM, |
| 284 | [Group1_83*8] = |
| 285 | DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM, |
| 286 | DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM, |
| 287 | DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM, |
| 288 | DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM, |
| 289 | [Group1A*8] = |
| 290 | DstMem | SrcNone | ModRM | Mov | Stack, 0, 0, 0, 0, 0, 0, 0, |
| 291 | [Group3_Byte*8] = |
| 292 | ByteOp | SrcImm | DstMem | ModRM, 0, |
| 293 | ByteOp | DstMem | SrcNone | ModRM, ByteOp | DstMem | SrcNone | ModRM, |
| 294 | 0, 0, 0, 0, |
| 295 | [Group3*8] = |
| 296 | DstMem | SrcImm | ModRM, 0, |
| 297 | DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM, |
| 298 | 0, 0, 0, 0, |
| 299 | [Group4*8] = |
| 300 | ByteOp | DstMem | SrcNone | ModRM, ByteOp | DstMem | SrcNone | ModRM, |
| 301 | 0, 0, 0, 0, 0, 0, |
| 302 | [Group5*8] = |
| 303 | DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM, |
| 304 | SrcMem | ModRM | Stack, 0, |
| 305 | SrcMem | ModRM | Stack, 0, SrcMem | ModRM | Stack, 0, |
| 306 | [Group7*8] = |
| 307 | 0, 0, ModRM | SrcMem, ModRM | SrcMem, |
| 308 | SrcNone | ModRM | DstMem | Mov, 0, |
| 309 | SrcMem16 | ModRM | Mov, SrcMem | ModRM | ByteOp, |
| 310 | }; |
| 311 | |
| 312 | static u32 group2_table[] = { |
| 313 | [Group7*8] = |
| 314 | SrcNone | ModRM, 0, 0, SrcNone | ModRM, |
| 315 | SrcNone | ModRM | DstMem | Mov, 0, |
| 316 | SrcMem16 | ModRM | Mov, 0, |
| 317 | }; |
| 318 | |
| 319 | /* EFLAGS bit definitions. */ |
| 320 | #define EFLG_OF (1<<11) |
| 321 | #define EFLG_DF (1<<10) |
| 322 | #define EFLG_SF (1<<7) |
| 323 | #define EFLG_ZF (1<<6) |
| 324 | #define EFLG_AF (1<<4) |
| 325 | #define EFLG_PF (1<<2) |
| 326 | #define EFLG_CF (1<<0) |
| 327 | |
| 328 | /* |
| 329 | * Instruction emulation: |
| 330 | * Most instructions are emulated directly via a fragment of inline assembly |
| 331 | * code. This allows us to save/restore EFLAGS and thus very easily pick up |
| 332 | * any modified flags. |
| 333 | */ |
| 334 | |
| 335 | #if defined(CONFIG_X86_64) |
| 336 | #define _LO32 "k" /* force 32-bit operand */ |
| 337 | #define _STK "%%rsp" /* stack pointer */ |
| 338 | #elif defined(__i386__) |
| 339 | #define _LO32 "" /* force 32-bit operand */ |
| 340 | #define _STK "%%esp" /* stack pointer */ |
| 341 | #endif |
| 342 | |
| 343 | /* |
| 344 | * These EFLAGS bits are restored from saved value during emulation, and |
| 345 | * any changes are written back to the saved value after emulation. |
| 346 | */ |
| 347 | #define EFLAGS_MASK (EFLG_OF|EFLG_SF|EFLG_ZF|EFLG_AF|EFLG_PF|EFLG_CF) |
| 348 | |
| 349 | /* Before executing instruction: restore necessary bits in EFLAGS. */ |
| 350 | #define _PRE_EFLAGS(_sav, _msk, _tmp) \ |
| 351 | /* EFLAGS = (_sav & _msk) | (EFLAGS & ~_msk); _sav &= ~_msk; */ \ |
| 352 | "movl %"_sav",%"_LO32 _tmp"; " \ |
| 353 | "push %"_tmp"; " \ |
| 354 | "push %"_tmp"; " \ |
| 355 | "movl %"_msk",%"_LO32 _tmp"; " \ |
| 356 | "andl %"_LO32 _tmp",("_STK"); " \ |
| 357 | "pushf; " \ |
| 358 | "notl %"_LO32 _tmp"; " \ |
| 359 | "andl %"_LO32 _tmp",("_STK"); " \ |
| 360 | "andl %"_LO32 _tmp","__stringify(BITS_PER_LONG/4)"("_STK"); " \ |
| 361 | "pop %"_tmp"; " \ |
| 362 | "orl %"_LO32 _tmp",("_STK"); " \ |
| 363 | "popf; " \ |
| 364 | "pop %"_sav"; " |
| 365 | |
| 366 | /* After executing instruction: write-back necessary bits in EFLAGS. */ |
| 367 | #define _POST_EFLAGS(_sav, _msk, _tmp) \ |
| 368 | /* _sav |= EFLAGS & _msk; */ \ |
| 369 | "pushf; " \ |
| 370 | "pop %"_tmp"; " \ |
| 371 | "andl %"_msk",%"_LO32 _tmp"; " \ |
| 372 | "orl %"_LO32 _tmp",%"_sav"; " |
| 373 | |
| 374 | #ifdef CONFIG_X86_64 |
| 375 | #define ON64(x) x |
| 376 | #else |
| 377 | #define ON64(x) |
| 378 | #endif |
| 379 | |
| 380 | #define ____emulate_2op(_op, _src, _dst, _eflags, _x, _y, _suffix) \ |
| 381 | do { \ |
| 382 | __asm__ __volatile__ ( \ |
| 383 | _PRE_EFLAGS("0", "4", "2") \ |
| 384 | _op _suffix " %"_x"3,%1; " \ |
| 385 | _POST_EFLAGS("0", "4", "2") \ |
| 386 | : "=m" (_eflags), "=m" ((_dst).val), \ |
| 387 | "=&r" (_tmp) \ |
| 388 | : _y ((_src).val), "i" (EFLAGS_MASK)); \ |
| 389 | } while (0) |
| 390 | |
| 391 | |
| 392 | /* Raw emulation: instruction has two explicit operands. */ |
| 393 | #define __emulate_2op_nobyte(_op,_src,_dst,_eflags,_wx,_wy,_lx,_ly,_qx,_qy) \ |
| 394 | do { \ |
| 395 | unsigned long _tmp; \ |
| 396 | \ |
| 397 | switch ((_dst).bytes) { \ |
| 398 | case 2: \ |
| 399 | ____emulate_2op(_op,_src,_dst,_eflags,_wx,_wy,"w"); \ |
| 400 | break; \ |
| 401 | case 4: \ |
| 402 | ____emulate_2op(_op,_src,_dst,_eflags,_lx,_ly,"l"); \ |
| 403 | break; \ |
| 404 | case 8: \ |
| 405 | ON64(____emulate_2op(_op,_src,_dst,_eflags,_qx,_qy,"q")); \ |
| 406 | break; \ |
| 407 | } \ |
| 408 | } while (0) |
| 409 | |
| 410 | #define __emulate_2op(_op,_src,_dst,_eflags,_bx,_by,_wx,_wy,_lx,_ly,_qx,_qy) \ |
| 411 | do { \ |
| 412 | unsigned long _tmp; \ |
| 413 | switch ((_dst).bytes) { \ |
| 414 | case 1: \ |
| 415 | ____emulate_2op(_op,_src,_dst,_eflags,_bx,_by,"b"); \ |
| 416 | break; \ |
| 417 | default: \ |
| 418 | __emulate_2op_nobyte(_op, _src, _dst, _eflags, \ |
| 419 | _wx, _wy, _lx, _ly, _qx, _qy); \ |
| 420 | break; \ |
| 421 | } \ |
| 422 | } while (0) |
| 423 | |
| 424 | /* Source operand is byte-sized and may be restricted to just %cl. */ |
| 425 | #define emulate_2op_SrcB(_op, _src, _dst, _eflags) \ |
| 426 | __emulate_2op(_op, _src, _dst, _eflags, \ |
| 427 | "b", "c", "b", "c", "b", "c", "b", "c") |
| 428 | |
| 429 | /* Source operand is byte, word, long or quad sized. */ |
| 430 | #define emulate_2op_SrcV(_op, _src, _dst, _eflags) \ |
| 431 | __emulate_2op(_op, _src, _dst, _eflags, \ |
| 432 | "b", "q", "w", "r", _LO32, "r", "", "r") |
| 433 | |
| 434 | /* Source operand is word, long or quad sized. */ |
| 435 | #define emulate_2op_SrcV_nobyte(_op, _src, _dst, _eflags) \ |
| 436 | __emulate_2op_nobyte(_op, _src, _dst, _eflags, \ |
| 437 | "w", "r", _LO32, "r", "", "r") |
| 438 | |
| 439 | /* Instruction has three operands and one operand is stored in ECX register */ |
| 440 | #define __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, _suffix, _type) \ |
| 441 | do { \ |
| 442 | unsigned long _tmp; \ |
| 443 | _type _clv = (_cl).val; \ |
| 444 | _type _srcv = (_src).val; \ |
| 445 | _type _dstv = (_dst).val; \ |
| 446 | \ |
| 447 | __asm__ __volatile__ ( \ |
| 448 | _PRE_EFLAGS("0", "5", "2") \ |
| 449 | _op _suffix " %4,%1 \n" \ |
| 450 | _POST_EFLAGS("0", "5", "2") \ |
| 451 | : "=m" (_eflags), "+r" (_dstv), "=&r" (_tmp) \ |
| 452 | : "c" (_clv) , "r" (_srcv), "i" (EFLAGS_MASK) \ |
| 453 | ); \ |
| 454 | \ |
| 455 | (_cl).val = (unsigned long) _clv; \ |
| 456 | (_src).val = (unsigned long) _srcv; \ |
| 457 | (_dst).val = (unsigned long) _dstv; \ |
| 458 | } while (0) |
| 459 | |
| 460 | #define emulate_2op_cl(_op, _cl, _src, _dst, _eflags) \ |
| 461 | do { \ |
| 462 | switch ((_dst).bytes) { \ |
| 463 | case 2: \ |
| 464 | __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \ |
| 465 | "w", unsigned short); \ |
| 466 | break; \ |
| 467 | case 4: \ |
| 468 | __emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \ |
| 469 | "l", unsigned int); \ |
| 470 | break; \ |
| 471 | case 8: \ |
| 472 | ON64(__emulate_2op_cl(_op, _cl, _src, _dst, _eflags, \ |
| 473 | "q", unsigned long)); \ |
| 474 | break; \ |
| 475 | } \ |
| 476 | } while (0) |
| 477 | |
| 478 | #define __emulate_1op(_op, _dst, _eflags, _suffix) \ |
| 479 | do { \ |
| 480 | unsigned long _tmp; \ |
| 481 | \ |
| 482 | __asm__ __volatile__ ( \ |
| 483 | _PRE_EFLAGS("0", "3", "2") \ |
| 484 | _op _suffix " %1; " \ |
| 485 | _POST_EFLAGS("0", "3", "2") \ |
| 486 | : "=m" (_eflags), "+m" ((_dst).val), \ |
| 487 | "=&r" (_tmp) \ |
| 488 | : "i" (EFLAGS_MASK)); \ |
| 489 | } while (0) |
| 490 | |
| 491 | /* Instruction has only one explicit operand (no source operand). */ |
| 492 | #define emulate_1op(_op, _dst, _eflags) \ |
| 493 | do { \ |
| 494 | switch ((_dst).bytes) { \ |
| 495 | case 1: __emulate_1op(_op, _dst, _eflags, "b"); break; \ |
| 496 | case 2: __emulate_1op(_op, _dst, _eflags, "w"); break; \ |
| 497 | case 4: __emulate_1op(_op, _dst, _eflags, "l"); break; \ |
| 498 | case 8: ON64(__emulate_1op(_op, _dst, _eflags, "q")); break; \ |
| 499 | } \ |
| 500 | } while (0) |
| 501 | |
| 502 | /* Fetch next part of the instruction being emulated. */ |
| 503 | #define insn_fetch(_type, _size, _eip) \ |
| 504 | ({ unsigned long _x; \ |
| 505 | rc = do_insn_fetch(ctxt, ops, (_eip), &_x, (_size)); \ |
| 506 | if (rc != 0) \ |
| 507 | goto done; \ |
| 508 | (_eip) += (_size); \ |
| 509 | (_type)_x; \ |
| 510 | }) |
| 511 | |
| 512 | static inline unsigned long ad_mask(struct decode_cache *c) |
| 513 | { |
| 514 | return (1UL << (c->ad_bytes << 3)) - 1; |
| 515 | } |
| 516 | |
| 517 | /* Access/update address held in a register, based on addressing mode. */ |
| 518 | static inline unsigned long |
| 519 | address_mask(struct decode_cache *c, unsigned long reg) |
| 520 | { |
| 521 | if (c->ad_bytes == sizeof(unsigned long)) |
| 522 | return reg; |
| 523 | else |
| 524 | return reg & ad_mask(c); |
| 525 | } |
| 526 | |
| 527 | static inline unsigned long |
| 528 | register_address(struct decode_cache *c, unsigned long base, unsigned long reg) |
| 529 | { |
| 530 | return base + address_mask(c, reg); |
| 531 | } |
| 532 | |
| 533 | static inline void |
| 534 | register_address_increment(struct decode_cache *c, unsigned long *reg, int inc) |
| 535 | { |
| 536 | if (c->ad_bytes == sizeof(unsigned long)) |
| 537 | *reg += inc; |
| 538 | else |
| 539 | *reg = (*reg & ~ad_mask(c)) | ((*reg + inc) & ad_mask(c)); |
| 540 | } |
| 541 | |
| 542 | static inline void jmp_rel(struct decode_cache *c, int rel) |
| 543 | { |
| 544 | register_address_increment(c, &c->eip, rel); |
| 545 | } |
| 546 | |
| 547 | static void set_seg_override(struct decode_cache *c, int seg) |
| 548 | { |
| 549 | c->has_seg_override = true; |
| 550 | c->seg_override = seg; |
| 551 | } |
| 552 | |
| 553 | static unsigned long seg_base(struct x86_emulate_ctxt *ctxt, int seg) |
| 554 | { |
| 555 | if (ctxt->mode == X86EMUL_MODE_PROT64 && seg < VCPU_SREG_FS) |
| 556 | return 0; |
| 557 | |
| 558 | return kvm_x86_ops->get_segment_base(ctxt->vcpu, seg); |
| 559 | } |
| 560 | |
| 561 | static unsigned long seg_override_base(struct x86_emulate_ctxt *ctxt, |
| 562 | struct decode_cache *c) |
| 563 | { |
| 564 | if (!c->has_seg_override) |
| 565 | return 0; |
| 566 | |
| 567 | return seg_base(ctxt, c->seg_override); |
| 568 | } |
| 569 | |
| 570 | static unsigned long es_base(struct x86_emulate_ctxt *ctxt) |
| 571 | { |
| 572 | return seg_base(ctxt, VCPU_SREG_ES); |
| 573 | } |
| 574 | |
| 575 | static unsigned long ss_base(struct x86_emulate_ctxt *ctxt) |
| 576 | { |
| 577 | return seg_base(ctxt, VCPU_SREG_SS); |
| 578 | } |
| 579 | |
| 580 | static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt, |
| 581 | struct x86_emulate_ops *ops, |
| 582 | unsigned long linear, u8 *dest) |
| 583 | { |
| 584 | struct fetch_cache *fc = &ctxt->decode.fetch; |
| 585 | int rc; |
| 586 | int size; |
| 587 | |
| 588 | if (linear < fc->start || linear >= fc->end) { |
| 589 | size = min(15UL, PAGE_SIZE - offset_in_page(linear)); |
| 590 | rc = ops->read_std(linear, fc->data, size, ctxt->vcpu); |
| 591 | if (rc) |
| 592 | return rc; |
| 593 | fc->start = linear; |
| 594 | fc->end = linear + size; |
| 595 | } |
| 596 | *dest = fc->data[linear - fc->start]; |
| 597 | return 0; |
| 598 | } |
| 599 | |
| 600 | static int do_insn_fetch(struct x86_emulate_ctxt *ctxt, |
| 601 | struct x86_emulate_ops *ops, |
| 602 | unsigned long eip, void *dest, unsigned size) |
| 603 | { |
| 604 | int rc = 0; |
| 605 | |
| 606 | eip += ctxt->cs_base; |
| 607 | while (size--) { |
| 608 | rc = do_fetch_insn_byte(ctxt, ops, eip++, dest++); |
| 609 | if (rc) |
| 610 | return rc; |
| 611 | } |
| 612 | return 0; |
| 613 | } |
| 614 | |
| 615 | /* |
| 616 | * Given the 'reg' portion of a ModRM byte, and a register block, return a |
| 617 | * pointer into the block that addresses the relevant register. |
| 618 | * @highbyte_regs specifies whether to decode AH,CH,DH,BH. |
| 619 | */ |
| 620 | static void *decode_register(u8 modrm_reg, unsigned long *regs, |
| 621 | int highbyte_regs) |
| 622 | { |
| 623 | void *p; |
| 624 | |
| 625 | p = ®s[modrm_reg]; |
| 626 | if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8) |
| 627 | p = (unsigned char *)®s[modrm_reg & 3] + 1; |
| 628 | return p; |
| 629 | } |
| 630 | |
| 631 | static int read_descriptor(struct x86_emulate_ctxt *ctxt, |
| 632 | struct x86_emulate_ops *ops, |
| 633 | void *ptr, |
| 634 | u16 *size, unsigned long *address, int op_bytes) |
| 635 | { |
| 636 | int rc; |
| 637 | |
| 638 | if (op_bytes == 2) |
| 639 | op_bytes = 3; |
| 640 | *address = 0; |
| 641 | rc = ops->read_std((unsigned long)ptr, (unsigned long *)size, 2, |
| 642 | ctxt->vcpu); |
| 643 | if (rc) |
| 644 | return rc; |
| 645 | rc = ops->read_std((unsigned long)ptr + 2, address, op_bytes, |
| 646 | ctxt->vcpu); |
| 647 | return rc; |
| 648 | } |
| 649 | |
| 650 | static int test_cc(unsigned int condition, unsigned int flags) |
| 651 | { |
| 652 | int rc = 0; |
| 653 | |
| 654 | switch ((condition & 15) >> 1) { |
| 655 | case 0: /* o */ |
| 656 | rc |= (flags & EFLG_OF); |
| 657 | break; |
| 658 | case 1: /* b/c/nae */ |
| 659 | rc |= (flags & EFLG_CF); |
| 660 | break; |
| 661 | case 2: /* z/e */ |
| 662 | rc |= (flags & EFLG_ZF); |
| 663 | break; |
| 664 | case 3: /* be/na */ |
| 665 | rc |= (flags & (EFLG_CF|EFLG_ZF)); |
| 666 | break; |
| 667 | case 4: /* s */ |
| 668 | rc |= (flags & EFLG_SF); |
| 669 | break; |
| 670 | case 5: /* p/pe */ |
| 671 | rc |= (flags & EFLG_PF); |
| 672 | break; |
| 673 | case 7: /* le/ng */ |
| 674 | rc |= (flags & EFLG_ZF); |
| 675 | /* fall through */ |
| 676 | case 6: /* l/nge */ |
| 677 | rc |= (!(flags & EFLG_SF) != !(flags & EFLG_OF)); |
| 678 | break; |
| 679 | } |
| 680 | |
| 681 | /* Odd condition identifiers (lsb == 1) have inverted sense. */ |
| 682 | return (!!rc ^ (condition & 1)); |
| 683 | } |
| 684 | |
| 685 | static void decode_register_operand(struct operand *op, |
| 686 | struct decode_cache *c, |
| 687 | int inhibit_bytereg) |
| 688 | { |
| 689 | unsigned reg = c->modrm_reg; |
| 690 | int highbyte_regs = c->rex_prefix == 0; |
| 691 | |
| 692 | if (!(c->d & ModRM)) |
| 693 | reg = (c->b & 7) | ((c->rex_prefix & 1) << 3); |
| 694 | op->type = OP_REG; |
| 695 | if ((c->d & ByteOp) && !inhibit_bytereg) { |
| 696 | op->ptr = decode_register(reg, c->regs, highbyte_regs); |
| 697 | op->val = *(u8 *)op->ptr; |
| 698 | op->bytes = 1; |
| 699 | } else { |
| 700 | op->ptr = decode_register(reg, c->regs, 0); |
| 701 | op->bytes = c->op_bytes; |
| 702 | switch (op->bytes) { |
| 703 | case 2: |
| 704 | op->val = *(u16 *)op->ptr; |
| 705 | break; |
| 706 | case 4: |
| 707 | op->val = *(u32 *)op->ptr; |
| 708 | break; |
| 709 | case 8: |
| 710 | op->val = *(u64 *) op->ptr; |
| 711 | break; |
| 712 | } |
| 713 | } |
| 714 | op->orig_val = op->val; |
| 715 | } |
| 716 | |
| 717 | static int decode_modrm(struct x86_emulate_ctxt *ctxt, |
| 718 | struct x86_emulate_ops *ops) |
| 719 | { |
| 720 | struct decode_cache *c = &ctxt->decode; |
| 721 | u8 sib; |
| 722 | int index_reg = 0, base_reg = 0, scale; |
| 723 | int rc = 0; |
| 724 | |
| 725 | if (c->rex_prefix) { |
| 726 | c->modrm_reg = (c->rex_prefix & 4) << 1; /* REX.R */ |
| 727 | index_reg = (c->rex_prefix & 2) << 2; /* REX.X */ |
| 728 | c->modrm_rm = base_reg = (c->rex_prefix & 1) << 3; /* REG.B */ |
| 729 | } |
| 730 | |
| 731 | c->modrm = insn_fetch(u8, 1, c->eip); |
| 732 | c->modrm_mod |= (c->modrm & 0xc0) >> 6; |
| 733 | c->modrm_reg |= (c->modrm & 0x38) >> 3; |
| 734 | c->modrm_rm |= (c->modrm & 0x07); |
| 735 | c->modrm_ea = 0; |
| 736 | c->use_modrm_ea = 1; |
| 737 | |
| 738 | if (c->modrm_mod == 3) { |
| 739 | c->modrm_ptr = decode_register(c->modrm_rm, |
| 740 | c->regs, c->d & ByteOp); |
| 741 | c->modrm_val = *(unsigned long *)c->modrm_ptr; |
| 742 | return rc; |
| 743 | } |
| 744 | |
| 745 | if (c->ad_bytes == 2) { |
| 746 | unsigned bx = c->regs[VCPU_REGS_RBX]; |
| 747 | unsigned bp = c->regs[VCPU_REGS_RBP]; |
| 748 | unsigned si = c->regs[VCPU_REGS_RSI]; |
| 749 | unsigned di = c->regs[VCPU_REGS_RDI]; |
| 750 | |
| 751 | /* 16-bit ModR/M decode. */ |
| 752 | switch (c->modrm_mod) { |
| 753 | case 0: |
| 754 | if (c->modrm_rm == 6) |
| 755 | c->modrm_ea += insn_fetch(u16, 2, c->eip); |
| 756 | break; |
| 757 | case 1: |
| 758 | c->modrm_ea += insn_fetch(s8, 1, c->eip); |
| 759 | break; |
| 760 | case 2: |
| 761 | c->modrm_ea += insn_fetch(u16, 2, c->eip); |
| 762 | break; |
| 763 | } |
| 764 | switch (c->modrm_rm) { |
| 765 | case 0: |
| 766 | c->modrm_ea += bx + si; |
| 767 | break; |
| 768 | case 1: |
| 769 | c->modrm_ea += bx + di; |
| 770 | break; |
| 771 | case 2: |
| 772 | c->modrm_ea += bp + si; |
| 773 | break; |
| 774 | case 3: |
| 775 | c->modrm_ea += bp + di; |
| 776 | break; |
| 777 | case 4: |
| 778 | c->modrm_ea += si; |
| 779 | break; |
| 780 | case 5: |
| 781 | c->modrm_ea += di; |
| 782 | break; |
| 783 | case 6: |
| 784 | if (c->modrm_mod != 0) |
| 785 | c->modrm_ea += bp; |
| 786 | break; |
| 787 | case 7: |
| 788 | c->modrm_ea += bx; |
| 789 | break; |
| 790 | } |
| 791 | if (c->modrm_rm == 2 || c->modrm_rm == 3 || |
| 792 | (c->modrm_rm == 6 && c->modrm_mod != 0)) |
| 793 | if (!c->has_seg_override) |
| 794 | set_seg_override(c, VCPU_SREG_SS); |
| 795 | c->modrm_ea = (u16)c->modrm_ea; |
| 796 | } else { |
| 797 | /* 32/64-bit ModR/M decode. */ |
| 798 | if ((c->modrm_rm & 7) == 4) { |
| 799 | sib = insn_fetch(u8, 1, c->eip); |
| 800 | index_reg |= (sib >> 3) & 7; |
| 801 | base_reg |= sib & 7; |
| 802 | scale = sib >> 6; |
| 803 | |
| 804 | if ((base_reg & 7) == 5 && c->modrm_mod == 0) |
| 805 | c->modrm_ea += insn_fetch(s32, 4, c->eip); |
| 806 | else |
| 807 | c->modrm_ea += c->regs[base_reg]; |
| 808 | if (index_reg != 4) |
| 809 | c->modrm_ea += c->regs[index_reg] << scale; |
| 810 | } else if ((c->modrm_rm & 7) == 5 && c->modrm_mod == 0) { |
| 811 | if (ctxt->mode == X86EMUL_MODE_PROT64) |
| 812 | c->rip_relative = 1; |
| 813 | } else |
| 814 | c->modrm_ea += c->regs[c->modrm_rm]; |
| 815 | switch (c->modrm_mod) { |
| 816 | case 0: |
| 817 | if (c->modrm_rm == 5) |
| 818 | c->modrm_ea += insn_fetch(s32, 4, c->eip); |
| 819 | break; |
| 820 | case 1: |
| 821 | c->modrm_ea += insn_fetch(s8, 1, c->eip); |
| 822 | break; |
| 823 | case 2: |
| 824 | c->modrm_ea += insn_fetch(s32, 4, c->eip); |
| 825 | break; |
| 826 | } |
| 827 | } |
| 828 | done: |
| 829 | return rc; |
| 830 | } |
| 831 | |
| 832 | static int decode_abs(struct x86_emulate_ctxt *ctxt, |
| 833 | struct x86_emulate_ops *ops) |
| 834 | { |
| 835 | struct decode_cache *c = &ctxt->decode; |
| 836 | int rc = 0; |
| 837 | |
| 838 | switch (c->ad_bytes) { |
| 839 | case 2: |
| 840 | c->modrm_ea = insn_fetch(u16, 2, c->eip); |
| 841 | break; |
| 842 | case 4: |
| 843 | c->modrm_ea = insn_fetch(u32, 4, c->eip); |
| 844 | break; |
| 845 | case 8: |
| 846 | c->modrm_ea = insn_fetch(u64, 8, c->eip); |
| 847 | break; |
| 848 | } |
| 849 | done: |
| 850 | return rc; |
| 851 | } |
| 852 | |
| 853 | int |
| 854 | x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) |
| 855 | { |
| 856 | struct decode_cache *c = &ctxt->decode; |
| 857 | int rc = 0; |
| 858 | int mode = ctxt->mode; |
| 859 | int def_op_bytes, def_ad_bytes, group; |
| 860 | |
| 861 | /* Shadow copy of register state. Committed on successful emulation. */ |
| 862 | |
| 863 | memset(c, 0, sizeof(struct decode_cache)); |
| 864 | c->eip = kvm_rip_read(ctxt->vcpu); |
| 865 | ctxt->cs_base = seg_base(ctxt, VCPU_SREG_CS); |
| 866 | memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs); |
| 867 | |
| 868 | switch (mode) { |
| 869 | case X86EMUL_MODE_REAL: |
| 870 | case X86EMUL_MODE_PROT16: |
| 871 | def_op_bytes = def_ad_bytes = 2; |
| 872 | break; |
| 873 | case X86EMUL_MODE_PROT32: |
| 874 | def_op_bytes = def_ad_bytes = 4; |
| 875 | break; |
| 876 | #ifdef CONFIG_X86_64 |
| 877 | case X86EMUL_MODE_PROT64: |
| 878 | def_op_bytes = 4; |
| 879 | def_ad_bytes = 8; |
| 880 | break; |
| 881 | #endif |
| 882 | default: |
| 883 | return -1; |
| 884 | } |
| 885 | |
| 886 | c->op_bytes = def_op_bytes; |
| 887 | c->ad_bytes = def_ad_bytes; |
| 888 | |
| 889 | /* Legacy prefixes. */ |
| 890 | for (;;) { |
| 891 | switch (c->b = insn_fetch(u8, 1, c->eip)) { |
| 892 | case 0x66: /* operand-size override */ |
| 893 | /* switch between 2/4 bytes */ |
| 894 | c->op_bytes = def_op_bytes ^ 6; |
| 895 | break; |
| 896 | case 0x67: /* address-size override */ |
| 897 | if (mode == X86EMUL_MODE_PROT64) |
| 898 | /* switch between 4/8 bytes */ |
| 899 | c->ad_bytes = def_ad_bytes ^ 12; |
| 900 | else |
| 901 | /* switch between 2/4 bytes */ |
| 902 | c->ad_bytes = def_ad_bytes ^ 6; |
| 903 | break; |
| 904 | case 0x26: /* ES override */ |
| 905 | case 0x2e: /* CS override */ |
| 906 | case 0x36: /* SS override */ |
| 907 | case 0x3e: /* DS override */ |
| 908 | set_seg_override(c, (c->b >> 3) & 3); |
| 909 | break; |
| 910 | case 0x64: /* FS override */ |
| 911 | case 0x65: /* GS override */ |
| 912 | set_seg_override(c, c->b & 7); |
| 913 | break; |
| 914 | case 0x40 ... 0x4f: /* REX */ |
| 915 | if (mode != X86EMUL_MODE_PROT64) |
| 916 | goto done_prefixes; |
| 917 | c->rex_prefix = c->b; |
| 918 | continue; |
| 919 | case 0xf0: /* LOCK */ |
| 920 | c->lock_prefix = 1; |
| 921 | break; |
| 922 | case 0xf2: /* REPNE/REPNZ */ |
| 923 | c->rep_prefix = REPNE_PREFIX; |
| 924 | break; |
| 925 | case 0xf3: /* REP/REPE/REPZ */ |
| 926 | c->rep_prefix = REPE_PREFIX; |
| 927 | break; |
| 928 | default: |
| 929 | goto done_prefixes; |
| 930 | } |
| 931 | |
| 932 | /* Any legacy prefix after a REX prefix nullifies its effect. */ |
| 933 | |
| 934 | c->rex_prefix = 0; |
| 935 | } |
| 936 | |
| 937 | done_prefixes: |
| 938 | |
| 939 | /* REX prefix. */ |
| 940 | if (c->rex_prefix) |
| 941 | if (c->rex_prefix & 8) |
| 942 | c->op_bytes = 8; /* REX.W */ |
| 943 | |
| 944 | /* Opcode byte(s). */ |
| 945 | c->d = opcode_table[c->b]; |
| 946 | if (c->d == 0) { |
| 947 | /* Two-byte opcode? */ |
| 948 | if (c->b == 0x0f) { |
| 949 | c->twobyte = 1; |
| 950 | c->b = insn_fetch(u8, 1, c->eip); |
| 951 | c->d = twobyte_table[c->b]; |
| 952 | } |
| 953 | } |
| 954 | |
| 955 | if (c->d & Group) { |
| 956 | group = c->d & GroupMask; |
| 957 | c->modrm = insn_fetch(u8, 1, c->eip); |
| 958 | --c->eip; |
| 959 | |
| 960 | group = (group << 3) + ((c->modrm >> 3) & 7); |
| 961 | if ((c->d & GroupDual) && (c->modrm >> 6) == 3) |
| 962 | c->d = group2_table[group]; |
| 963 | else |
| 964 | c->d = group_table[group]; |
| 965 | } |
| 966 | |
| 967 | /* Unrecognised? */ |
| 968 | if (c->d == 0) { |
| 969 | DPRINTF("Cannot emulate %02x\n", c->b); |
| 970 | return -1; |
| 971 | } |
| 972 | |
| 973 | if (mode == X86EMUL_MODE_PROT64 && (c->d & Stack)) |
| 974 | c->op_bytes = 8; |
| 975 | |
| 976 | /* ModRM and SIB bytes. */ |
| 977 | if (c->d & ModRM) |
| 978 | rc = decode_modrm(ctxt, ops); |
| 979 | else if (c->d & MemAbs) |
| 980 | rc = decode_abs(ctxt, ops); |
| 981 | if (rc) |
| 982 | goto done; |
| 983 | |
| 984 | if (!c->has_seg_override) |
| 985 | set_seg_override(c, VCPU_SREG_DS); |
| 986 | |
| 987 | if (!(!c->twobyte && c->b == 0x8d)) |
| 988 | c->modrm_ea += seg_override_base(ctxt, c); |
| 989 | |
| 990 | if (c->ad_bytes != 8) |
| 991 | c->modrm_ea = (u32)c->modrm_ea; |
| 992 | /* |
| 993 | * Decode and fetch the source operand: register, memory |
| 994 | * or immediate. |
| 995 | */ |
| 996 | switch (c->d & SrcMask) { |
| 997 | case SrcNone: |
| 998 | break; |
| 999 | case SrcReg: |
| 1000 | decode_register_operand(&c->src, c, 0); |
| 1001 | break; |
| 1002 | case SrcMem16: |
| 1003 | c->src.bytes = 2; |
| 1004 | goto srcmem_common; |
| 1005 | case SrcMem32: |
| 1006 | c->src.bytes = 4; |
| 1007 | goto srcmem_common; |
| 1008 | case SrcMem: |
| 1009 | c->src.bytes = (c->d & ByteOp) ? 1 : |
| 1010 | c->op_bytes; |
| 1011 | /* Don't fetch the address for invlpg: it could be unmapped. */ |
| 1012 | if (c->twobyte && c->b == 0x01 && c->modrm_reg == 7) |
| 1013 | break; |
| 1014 | srcmem_common: |
| 1015 | /* |
| 1016 | * For instructions with a ModR/M byte, switch to register |
| 1017 | * access if Mod = 3. |
| 1018 | */ |
| 1019 | if ((c->d & ModRM) && c->modrm_mod == 3) { |
| 1020 | c->src.type = OP_REG; |
| 1021 | c->src.val = c->modrm_val; |
| 1022 | c->src.ptr = c->modrm_ptr; |
| 1023 | break; |
| 1024 | } |
| 1025 | c->src.type = OP_MEM; |
| 1026 | break; |
| 1027 | case SrcImm: |
| 1028 | c->src.type = OP_IMM; |
| 1029 | c->src.ptr = (unsigned long *)c->eip; |
| 1030 | c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1031 | if (c->src.bytes == 8) |
| 1032 | c->src.bytes = 4; |
| 1033 | /* NB. Immediates are sign-extended as necessary. */ |
| 1034 | switch (c->src.bytes) { |
| 1035 | case 1: |
| 1036 | c->src.val = insn_fetch(s8, 1, c->eip); |
| 1037 | break; |
| 1038 | case 2: |
| 1039 | c->src.val = insn_fetch(s16, 2, c->eip); |
| 1040 | break; |
| 1041 | case 4: |
| 1042 | c->src.val = insn_fetch(s32, 4, c->eip); |
| 1043 | break; |
| 1044 | } |
| 1045 | break; |
| 1046 | case SrcImmByte: |
| 1047 | c->src.type = OP_IMM; |
| 1048 | c->src.ptr = (unsigned long *)c->eip; |
| 1049 | c->src.bytes = 1; |
| 1050 | c->src.val = insn_fetch(s8, 1, c->eip); |
| 1051 | break; |
| 1052 | case SrcOne: |
| 1053 | c->src.bytes = 1; |
| 1054 | c->src.val = 1; |
| 1055 | break; |
| 1056 | } |
| 1057 | |
| 1058 | /* |
| 1059 | * Decode and fetch the second source operand: register, memory |
| 1060 | * or immediate. |
| 1061 | */ |
| 1062 | switch (c->d & Src2Mask) { |
| 1063 | case Src2None: |
| 1064 | break; |
| 1065 | case Src2CL: |
| 1066 | c->src2.bytes = 1; |
| 1067 | c->src2.val = c->regs[VCPU_REGS_RCX] & 0x8; |
| 1068 | break; |
| 1069 | case Src2ImmByte: |
| 1070 | c->src2.type = OP_IMM; |
| 1071 | c->src2.ptr = (unsigned long *)c->eip; |
| 1072 | c->src2.bytes = 1; |
| 1073 | c->src2.val = insn_fetch(u8, 1, c->eip); |
| 1074 | break; |
| 1075 | case Src2Imm16: |
| 1076 | c->src2.type = OP_IMM; |
| 1077 | c->src2.ptr = (unsigned long *)c->eip; |
| 1078 | c->src2.bytes = 2; |
| 1079 | c->src2.val = insn_fetch(u16, 2, c->eip); |
| 1080 | break; |
| 1081 | case Src2One: |
| 1082 | c->src2.bytes = 1; |
| 1083 | c->src2.val = 1; |
| 1084 | break; |
| 1085 | } |
| 1086 | |
| 1087 | /* Decode and fetch the destination operand: register or memory. */ |
| 1088 | switch (c->d & DstMask) { |
| 1089 | case ImplicitOps: |
| 1090 | /* Special instructions do their own operand decoding. */ |
| 1091 | return 0; |
| 1092 | case DstReg: |
| 1093 | decode_register_operand(&c->dst, c, |
| 1094 | c->twobyte && (c->b == 0xb6 || c->b == 0xb7)); |
| 1095 | break; |
| 1096 | case DstMem: |
| 1097 | if ((c->d & ModRM) && c->modrm_mod == 3) { |
| 1098 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1099 | c->dst.type = OP_REG; |
| 1100 | c->dst.val = c->dst.orig_val = c->modrm_val; |
| 1101 | c->dst.ptr = c->modrm_ptr; |
| 1102 | break; |
| 1103 | } |
| 1104 | c->dst.type = OP_MEM; |
| 1105 | break; |
| 1106 | case DstAcc: |
| 1107 | c->dst.type = OP_REG; |
| 1108 | c->dst.bytes = c->op_bytes; |
| 1109 | c->dst.ptr = &c->regs[VCPU_REGS_RAX]; |
| 1110 | switch (c->op_bytes) { |
| 1111 | case 1: |
| 1112 | c->dst.val = *(u8 *)c->dst.ptr; |
| 1113 | break; |
| 1114 | case 2: |
| 1115 | c->dst.val = *(u16 *)c->dst.ptr; |
| 1116 | break; |
| 1117 | case 4: |
| 1118 | c->dst.val = *(u32 *)c->dst.ptr; |
| 1119 | break; |
| 1120 | } |
| 1121 | c->dst.orig_val = c->dst.val; |
| 1122 | break; |
| 1123 | } |
| 1124 | |
| 1125 | if (c->rip_relative) |
| 1126 | c->modrm_ea += c->eip; |
| 1127 | |
| 1128 | done: |
| 1129 | return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; |
| 1130 | } |
| 1131 | |
| 1132 | static inline void emulate_push(struct x86_emulate_ctxt *ctxt) |
| 1133 | { |
| 1134 | struct decode_cache *c = &ctxt->decode; |
| 1135 | |
| 1136 | c->dst.type = OP_MEM; |
| 1137 | c->dst.bytes = c->op_bytes; |
| 1138 | c->dst.val = c->src.val; |
| 1139 | register_address_increment(c, &c->regs[VCPU_REGS_RSP], -c->op_bytes); |
| 1140 | c->dst.ptr = (void *) register_address(c, ss_base(ctxt), |
| 1141 | c->regs[VCPU_REGS_RSP]); |
| 1142 | } |
| 1143 | |
| 1144 | static int emulate_pop(struct x86_emulate_ctxt *ctxt, |
| 1145 | struct x86_emulate_ops *ops, |
| 1146 | void *dest, int len) |
| 1147 | { |
| 1148 | struct decode_cache *c = &ctxt->decode; |
| 1149 | int rc; |
| 1150 | |
| 1151 | rc = ops->read_emulated(register_address(c, ss_base(ctxt), |
| 1152 | c->regs[VCPU_REGS_RSP]), |
| 1153 | dest, len, ctxt->vcpu); |
| 1154 | if (rc != 0) |
| 1155 | return rc; |
| 1156 | |
| 1157 | register_address_increment(c, &c->regs[VCPU_REGS_RSP], len); |
| 1158 | return rc; |
| 1159 | } |
| 1160 | |
| 1161 | static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt, |
| 1162 | struct x86_emulate_ops *ops) |
| 1163 | { |
| 1164 | struct decode_cache *c = &ctxt->decode; |
| 1165 | int rc; |
| 1166 | |
| 1167 | rc = emulate_pop(ctxt, ops, &c->dst.val, c->dst.bytes); |
| 1168 | if (rc != 0) |
| 1169 | return rc; |
| 1170 | return 0; |
| 1171 | } |
| 1172 | |
| 1173 | static inline void emulate_grp2(struct x86_emulate_ctxt *ctxt) |
| 1174 | { |
| 1175 | struct decode_cache *c = &ctxt->decode; |
| 1176 | switch (c->modrm_reg) { |
| 1177 | case 0: /* rol */ |
| 1178 | emulate_2op_SrcB("rol", c->src, c->dst, ctxt->eflags); |
| 1179 | break; |
| 1180 | case 1: /* ror */ |
| 1181 | emulate_2op_SrcB("ror", c->src, c->dst, ctxt->eflags); |
| 1182 | break; |
| 1183 | case 2: /* rcl */ |
| 1184 | emulate_2op_SrcB("rcl", c->src, c->dst, ctxt->eflags); |
| 1185 | break; |
| 1186 | case 3: /* rcr */ |
| 1187 | emulate_2op_SrcB("rcr", c->src, c->dst, ctxt->eflags); |
| 1188 | break; |
| 1189 | case 4: /* sal/shl */ |
| 1190 | case 6: /* sal/shl */ |
| 1191 | emulate_2op_SrcB("sal", c->src, c->dst, ctxt->eflags); |
| 1192 | break; |
| 1193 | case 5: /* shr */ |
| 1194 | emulate_2op_SrcB("shr", c->src, c->dst, ctxt->eflags); |
| 1195 | break; |
| 1196 | case 7: /* sar */ |
| 1197 | emulate_2op_SrcB("sar", c->src, c->dst, ctxt->eflags); |
| 1198 | break; |
| 1199 | } |
| 1200 | } |
| 1201 | |
| 1202 | static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt, |
| 1203 | struct x86_emulate_ops *ops) |
| 1204 | { |
| 1205 | struct decode_cache *c = &ctxt->decode; |
| 1206 | int rc = 0; |
| 1207 | |
| 1208 | switch (c->modrm_reg) { |
| 1209 | case 0 ... 1: /* test */ |
| 1210 | emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags); |
| 1211 | break; |
| 1212 | case 2: /* not */ |
| 1213 | c->dst.val = ~c->dst.val; |
| 1214 | break; |
| 1215 | case 3: /* neg */ |
| 1216 | emulate_1op("neg", c->dst, ctxt->eflags); |
| 1217 | break; |
| 1218 | default: |
| 1219 | DPRINTF("Cannot emulate %02x\n", c->b); |
| 1220 | rc = X86EMUL_UNHANDLEABLE; |
| 1221 | break; |
| 1222 | } |
| 1223 | return rc; |
| 1224 | } |
| 1225 | |
| 1226 | static inline int emulate_grp45(struct x86_emulate_ctxt *ctxt, |
| 1227 | struct x86_emulate_ops *ops) |
| 1228 | { |
| 1229 | struct decode_cache *c = &ctxt->decode; |
| 1230 | |
| 1231 | switch (c->modrm_reg) { |
| 1232 | case 0: /* inc */ |
| 1233 | emulate_1op("inc", c->dst, ctxt->eflags); |
| 1234 | break; |
| 1235 | case 1: /* dec */ |
| 1236 | emulate_1op("dec", c->dst, ctxt->eflags); |
| 1237 | break; |
| 1238 | case 2: /* call near abs */ { |
| 1239 | long int old_eip; |
| 1240 | old_eip = c->eip; |
| 1241 | c->eip = c->src.val; |
| 1242 | c->src.val = old_eip; |
| 1243 | emulate_push(ctxt); |
| 1244 | break; |
| 1245 | } |
| 1246 | case 4: /* jmp abs */ |
| 1247 | c->eip = c->src.val; |
| 1248 | break; |
| 1249 | case 6: /* push */ |
| 1250 | emulate_push(ctxt); |
| 1251 | break; |
| 1252 | } |
| 1253 | return 0; |
| 1254 | } |
| 1255 | |
| 1256 | static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt, |
| 1257 | struct x86_emulate_ops *ops, |
| 1258 | unsigned long memop) |
| 1259 | { |
| 1260 | struct decode_cache *c = &ctxt->decode; |
| 1261 | u64 old, new; |
| 1262 | int rc; |
| 1263 | |
| 1264 | rc = ops->read_emulated(memop, &old, 8, ctxt->vcpu); |
| 1265 | if (rc != 0) |
| 1266 | return rc; |
| 1267 | |
| 1268 | if (((u32) (old >> 0) != (u32) c->regs[VCPU_REGS_RAX]) || |
| 1269 | ((u32) (old >> 32) != (u32) c->regs[VCPU_REGS_RDX])) { |
| 1270 | |
| 1271 | c->regs[VCPU_REGS_RAX] = (u32) (old >> 0); |
| 1272 | c->regs[VCPU_REGS_RDX] = (u32) (old >> 32); |
| 1273 | ctxt->eflags &= ~EFLG_ZF; |
| 1274 | |
| 1275 | } else { |
| 1276 | new = ((u64)c->regs[VCPU_REGS_RCX] << 32) | |
| 1277 | (u32) c->regs[VCPU_REGS_RBX]; |
| 1278 | |
| 1279 | rc = ops->cmpxchg_emulated(memop, &old, &new, 8, ctxt->vcpu); |
| 1280 | if (rc != 0) |
| 1281 | return rc; |
| 1282 | ctxt->eflags |= EFLG_ZF; |
| 1283 | } |
| 1284 | return 0; |
| 1285 | } |
| 1286 | |
| 1287 | static int emulate_ret_far(struct x86_emulate_ctxt *ctxt, |
| 1288 | struct x86_emulate_ops *ops) |
| 1289 | { |
| 1290 | struct decode_cache *c = &ctxt->decode; |
| 1291 | int rc; |
| 1292 | unsigned long cs; |
| 1293 | |
| 1294 | rc = emulate_pop(ctxt, ops, &c->eip, c->op_bytes); |
| 1295 | if (rc) |
| 1296 | return rc; |
| 1297 | if (c->op_bytes == 4) |
| 1298 | c->eip = (u32)c->eip; |
| 1299 | rc = emulate_pop(ctxt, ops, &cs, c->op_bytes); |
| 1300 | if (rc) |
| 1301 | return rc; |
| 1302 | rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)cs, 1, VCPU_SREG_CS); |
| 1303 | return rc; |
| 1304 | } |
| 1305 | |
| 1306 | static inline int writeback(struct x86_emulate_ctxt *ctxt, |
| 1307 | struct x86_emulate_ops *ops) |
| 1308 | { |
| 1309 | int rc; |
| 1310 | struct decode_cache *c = &ctxt->decode; |
| 1311 | |
| 1312 | switch (c->dst.type) { |
| 1313 | case OP_REG: |
| 1314 | /* The 4-byte case *is* correct: |
| 1315 | * in 64-bit mode we zero-extend. |
| 1316 | */ |
| 1317 | switch (c->dst.bytes) { |
| 1318 | case 1: |
| 1319 | *(u8 *)c->dst.ptr = (u8)c->dst.val; |
| 1320 | break; |
| 1321 | case 2: |
| 1322 | *(u16 *)c->dst.ptr = (u16)c->dst.val; |
| 1323 | break; |
| 1324 | case 4: |
| 1325 | *c->dst.ptr = (u32)c->dst.val; |
| 1326 | break; /* 64b: zero-ext */ |
| 1327 | case 8: |
| 1328 | *c->dst.ptr = c->dst.val; |
| 1329 | break; |
| 1330 | } |
| 1331 | break; |
| 1332 | case OP_MEM: |
| 1333 | if (c->lock_prefix) |
| 1334 | rc = ops->cmpxchg_emulated( |
| 1335 | (unsigned long)c->dst.ptr, |
| 1336 | &c->dst.orig_val, |
| 1337 | &c->dst.val, |
| 1338 | c->dst.bytes, |
| 1339 | ctxt->vcpu); |
| 1340 | else |
| 1341 | rc = ops->write_emulated( |
| 1342 | (unsigned long)c->dst.ptr, |
| 1343 | &c->dst.val, |
| 1344 | c->dst.bytes, |
| 1345 | ctxt->vcpu); |
| 1346 | if (rc != 0) |
| 1347 | return rc; |
| 1348 | break; |
| 1349 | case OP_NONE: |
| 1350 | /* no writeback */ |
| 1351 | break; |
| 1352 | default: |
| 1353 | break; |
| 1354 | } |
| 1355 | return 0; |
| 1356 | } |
| 1357 | |
| 1358 | int |
| 1359 | x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) |
| 1360 | { |
| 1361 | unsigned long memop = 0; |
| 1362 | u64 msr_data; |
| 1363 | unsigned long saved_eip = 0; |
| 1364 | struct decode_cache *c = &ctxt->decode; |
| 1365 | unsigned int port; |
| 1366 | int io_dir_in; |
| 1367 | int rc = 0; |
| 1368 | |
| 1369 | /* Shadow copy of register state. Committed on successful emulation. |
| 1370 | * NOTE: we can copy them from vcpu as x86_decode_insn() doesn't |
| 1371 | * modify them. |
| 1372 | */ |
| 1373 | |
| 1374 | memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs); |
| 1375 | saved_eip = c->eip; |
| 1376 | |
| 1377 | if (((c->d & ModRM) && (c->modrm_mod != 3)) || (c->d & MemAbs)) |
| 1378 | memop = c->modrm_ea; |
| 1379 | |
| 1380 | if (c->rep_prefix && (c->d & String)) { |
| 1381 | /* All REP prefixes have the same first termination condition */ |
| 1382 | if (c->regs[VCPU_REGS_RCX] == 0) { |
| 1383 | kvm_rip_write(ctxt->vcpu, c->eip); |
| 1384 | goto done; |
| 1385 | } |
| 1386 | /* The second termination condition only applies for REPE |
| 1387 | * and REPNE. Test if the repeat string operation prefix is |
| 1388 | * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the |
| 1389 | * corresponding termination condition according to: |
| 1390 | * - if REPE/REPZ and ZF = 0 then done |
| 1391 | * - if REPNE/REPNZ and ZF = 1 then done |
| 1392 | */ |
| 1393 | if ((c->b == 0xa6) || (c->b == 0xa7) || |
| 1394 | (c->b == 0xae) || (c->b == 0xaf)) { |
| 1395 | if ((c->rep_prefix == REPE_PREFIX) && |
| 1396 | ((ctxt->eflags & EFLG_ZF) == 0)) { |
| 1397 | kvm_rip_write(ctxt->vcpu, c->eip); |
| 1398 | goto done; |
| 1399 | } |
| 1400 | if ((c->rep_prefix == REPNE_PREFIX) && |
| 1401 | ((ctxt->eflags & EFLG_ZF) == EFLG_ZF)) { |
| 1402 | kvm_rip_write(ctxt->vcpu, c->eip); |
| 1403 | goto done; |
| 1404 | } |
| 1405 | } |
| 1406 | c->regs[VCPU_REGS_RCX]--; |
| 1407 | c->eip = kvm_rip_read(ctxt->vcpu); |
| 1408 | } |
| 1409 | |
| 1410 | if (c->src.type == OP_MEM) { |
| 1411 | c->src.ptr = (unsigned long *)memop; |
| 1412 | c->src.val = 0; |
| 1413 | rc = ops->read_emulated((unsigned long)c->src.ptr, |
| 1414 | &c->src.val, |
| 1415 | c->src.bytes, |
| 1416 | ctxt->vcpu); |
| 1417 | if (rc != 0) |
| 1418 | goto done; |
| 1419 | c->src.orig_val = c->src.val; |
| 1420 | } |
| 1421 | |
| 1422 | if ((c->d & DstMask) == ImplicitOps) |
| 1423 | goto special_insn; |
| 1424 | |
| 1425 | |
| 1426 | if (c->dst.type == OP_MEM) { |
| 1427 | c->dst.ptr = (unsigned long *)memop; |
| 1428 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1429 | c->dst.val = 0; |
| 1430 | if (c->d & BitOp) { |
| 1431 | unsigned long mask = ~(c->dst.bytes * 8 - 1); |
| 1432 | |
| 1433 | c->dst.ptr = (void *)c->dst.ptr + |
| 1434 | (c->src.val & mask) / 8; |
| 1435 | } |
| 1436 | if (!(c->d & Mov) && |
| 1437 | /* optimisation - avoid slow emulated read */ |
| 1438 | ((rc = ops->read_emulated((unsigned long)c->dst.ptr, |
| 1439 | &c->dst.val, |
| 1440 | c->dst.bytes, ctxt->vcpu)) != 0)) |
| 1441 | goto done; |
| 1442 | } |
| 1443 | c->dst.orig_val = c->dst.val; |
| 1444 | |
| 1445 | special_insn: |
| 1446 | |
| 1447 | if (c->twobyte) |
| 1448 | goto twobyte_insn; |
| 1449 | |
| 1450 | switch (c->b) { |
| 1451 | case 0x00 ... 0x05: |
| 1452 | add: /* add */ |
| 1453 | emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags); |
| 1454 | break; |
| 1455 | case 0x08 ... 0x0d: |
| 1456 | or: /* or */ |
| 1457 | emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags); |
| 1458 | break; |
| 1459 | case 0x10 ... 0x15: |
| 1460 | adc: /* adc */ |
| 1461 | emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags); |
| 1462 | break; |
| 1463 | case 0x18 ... 0x1d: |
| 1464 | sbb: /* sbb */ |
| 1465 | emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags); |
| 1466 | break; |
| 1467 | case 0x20 ... 0x25: |
| 1468 | and: /* and */ |
| 1469 | emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags); |
| 1470 | break; |
| 1471 | case 0x28 ... 0x2d: |
| 1472 | sub: /* sub */ |
| 1473 | emulate_2op_SrcV("sub", c->src, c->dst, ctxt->eflags); |
| 1474 | break; |
| 1475 | case 0x30 ... 0x35: |
| 1476 | xor: /* xor */ |
| 1477 | emulate_2op_SrcV("xor", c->src, c->dst, ctxt->eflags); |
| 1478 | break; |
| 1479 | case 0x38 ... 0x3d: |
| 1480 | cmp: /* cmp */ |
| 1481 | emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags); |
| 1482 | break; |
| 1483 | case 0x40 ... 0x47: /* inc r16/r32 */ |
| 1484 | emulate_1op("inc", c->dst, ctxt->eflags); |
| 1485 | break; |
| 1486 | case 0x48 ... 0x4f: /* dec r16/r32 */ |
| 1487 | emulate_1op("dec", c->dst, ctxt->eflags); |
| 1488 | break; |
| 1489 | case 0x50 ... 0x57: /* push reg */ |
| 1490 | emulate_push(ctxt); |
| 1491 | break; |
| 1492 | case 0x58 ... 0x5f: /* pop reg */ |
| 1493 | pop_instruction: |
| 1494 | rc = emulate_pop(ctxt, ops, &c->dst.val, c->op_bytes); |
| 1495 | if (rc != 0) |
| 1496 | goto done; |
| 1497 | break; |
| 1498 | case 0x63: /* movsxd */ |
| 1499 | if (ctxt->mode != X86EMUL_MODE_PROT64) |
| 1500 | goto cannot_emulate; |
| 1501 | c->dst.val = (s32) c->src.val; |
| 1502 | break; |
| 1503 | case 0x68: /* push imm */ |
| 1504 | case 0x6a: /* push imm8 */ |
| 1505 | emulate_push(ctxt); |
| 1506 | break; |
| 1507 | case 0x6c: /* insb */ |
| 1508 | case 0x6d: /* insw/insd */ |
| 1509 | if (kvm_emulate_pio_string(ctxt->vcpu, NULL, |
| 1510 | 1, |
| 1511 | (c->d & ByteOp) ? 1 : c->op_bytes, |
| 1512 | c->rep_prefix ? |
| 1513 | address_mask(c, c->regs[VCPU_REGS_RCX]) : 1, |
| 1514 | (ctxt->eflags & EFLG_DF), |
| 1515 | register_address(c, es_base(ctxt), |
| 1516 | c->regs[VCPU_REGS_RDI]), |
| 1517 | c->rep_prefix, |
| 1518 | c->regs[VCPU_REGS_RDX]) == 0) { |
| 1519 | c->eip = saved_eip; |
| 1520 | return -1; |
| 1521 | } |
| 1522 | return 0; |
| 1523 | case 0x6e: /* outsb */ |
| 1524 | case 0x6f: /* outsw/outsd */ |
| 1525 | if (kvm_emulate_pio_string(ctxt->vcpu, NULL, |
| 1526 | 0, |
| 1527 | (c->d & ByteOp) ? 1 : c->op_bytes, |
| 1528 | c->rep_prefix ? |
| 1529 | address_mask(c, c->regs[VCPU_REGS_RCX]) : 1, |
| 1530 | (ctxt->eflags & EFLG_DF), |
| 1531 | register_address(c, |
| 1532 | seg_override_base(ctxt, c), |
| 1533 | c->regs[VCPU_REGS_RSI]), |
| 1534 | c->rep_prefix, |
| 1535 | c->regs[VCPU_REGS_RDX]) == 0) { |
| 1536 | c->eip = saved_eip; |
| 1537 | return -1; |
| 1538 | } |
| 1539 | return 0; |
| 1540 | case 0x70 ... 0x7f: /* jcc (short) */ |
| 1541 | if (test_cc(c->b, ctxt->eflags)) |
| 1542 | jmp_rel(c, c->src.val); |
| 1543 | break; |
| 1544 | case 0x80 ... 0x83: /* Grp1 */ |
| 1545 | switch (c->modrm_reg) { |
| 1546 | case 0: |
| 1547 | goto add; |
| 1548 | case 1: |
| 1549 | goto or; |
| 1550 | case 2: |
| 1551 | goto adc; |
| 1552 | case 3: |
| 1553 | goto sbb; |
| 1554 | case 4: |
| 1555 | goto and; |
| 1556 | case 5: |
| 1557 | goto sub; |
| 1558 | case 6: |
| 1559 | goto xor; |
| 1560 | case 7: |
| 1561 | goto cmp; |
| 1562 | } |
| 1563 | break; |
| 1564 | case 0x84 ... 0x85: |
| 1565 | emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags); |
| 1566 | break; |
| 1567 | case 0x86 ... 0x87: /* xchg */ |
| 1568 | xchg: |
| 1569 | /* Write back the register source. */ |
| 1570 | switch (c->dst.bytes) { |
| 1571 | case 1: |
| 1572 | *(u8 *) c->src.ptr = (u8) c->dst.val; |
| 1573 | break; |
| 1574 | case 2: |
| 1575 | *(u16 *) c->src.ptr = (u16) c->dst.val; |
| 1576 | break; |
| 1577 | case 4: |
| 1578 | *c->src.ptr = (u32) c->dst.val; |
| 1579 | break; /* 64b reg: zero-extend */ |
| 1580 | case 8: |
| 1581 | *c->src.ptr = c->dst.val; |
| 1582 | break; |
| 1583 | } |
| 1584 | /* |
| 1585 | * Write back the memory destination with implicit LOCK |
| 1586 | * prefix. |
| 1587 | */ |
| 1588 | c->dst.val = c->src.val; |
| 1589 | c->lock_prefix = 1; |
| 1590 | break; |
| 1591 | case 0x88 ... 0x8b: /* mov */ |
| 1592 | goto mov; |
| 1593 | case 0x8c: { /* mov r/m, sreg */ |
| 1594 | struct kvm_segment segreg; |
| 1595 | |
| 1596 | if (c->modrm_reg <= 5) |
| 1597 | kvm_get_segment(ctxt->vcpu, &segreg, c->modrm_reg); |
| 1598 | else { |
| 1599 | printk(KERN_INFO "0x8c: Invalid segreg in modrm byte 0x%02x\n", |
| 1600 | c->modrm); |
| 1601 | goto cannot_emulate; |
| 1602 | } |
| 1603 | c->dst.val = segreg.selector; |
| 1604 | break; |
| 1605 | } |
| 1606 | case 0x8d: /* lea r16/r32, m */ |
| 1607 | c->dst.val = c->modrm_ea; |
| 1608 | break; |
| 1609 | case 0x8e: { /* mov seg, r/m16 */ |
| 1610 | uint16_t sel; |
| 1611 | int type_bits; |
| 1612 | int err; |
| 1613 | |
| 1614 | sel = c->src.val; |
| 1615 | if (c->modrm_reg <= 5) { |
| 1616 | type_bits = (c->modrm_reg == 1) ? 9 : 1; |
| 1617 | err = kvm_load_segment_descriptor(ctxt->vcpu, sel, |
| 1618 | type_bits, c->modrm_reg); |
| 1619 | } else { |
| 1620 | printk(KERN_INFO "Invalid segreg in modrm byte 0x%02x\n", |
| 1621 | c->modrm); |
| 1622 | goto cannot_emulate; |
| 1623 | } |
| 1624 | |
| 1625 | if (err < 0) |
| 1626 | goto cannot_emulate; |
| 1627 | |
| 1628 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1629 | break; |
| 1630 | } |
| 1631 | case 0x8f: /* pop (sole member of Grp1a) */ |
| 1632 | rc = emulate_grp1a(ctxt, ops); |
| 1633 | if (rc != 0) |
| 1634 | goto done; |
| 1635 | break; |
| 1636 | case 0x90: /* nop / xchg r8,rax */ |
| 1637 | if (!(c->rex_prefix & 1)) { /* nop */ |
| 1638 | c->dst.type = OP_NONE; |
| 1639 | break; |
| 1640 | } |
| 1641 | case 0x91 ... 0x97: /* xchg reg,rax */ |
| 1642 | c->src.type = c->dst.type = OP_REG; |
| 1643 | c->src.bytes = c->dst.bytes = c->op_bytes; |
| 1644 | c->src.ptr = (unsigned long *) &c->regs[VCPU_REGS_RAX]; |
| 1645 | c->src.val = *(c->src.ptr); |
| 1646 | goto xchg; |
| 1647 | case 0x9c: /* pushf */ |
| 1648 | c->src.val = (unsigned long) ctxt->eflags; |
| 1649 | emulate_push(ctxt); |
| 1650 | break; |
| 1651 | case 0x9d: /* popf */ |
| 1652 | c->dst.type = OP_REG; |
| 1653 | c->dst.ptr = (unsigned long *) &ctxt->eflags; |
| 1654 | c->dst.bytes = c->op_bytes; |
| 1655 | goto pop_instruction; |
| 1656 | case 0xa0 ... 0xa1: /* mov */ |
| 1657 | c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX]; |
| 1658 | c->dst.val = c->src.val; |
| 1659 | break; |
| 1660 | case 0xa2 ... 0xa3: /* mov */ |
| 1661 | c->dst.val = (unsigned long)c->regs[VCPU_REGS_RAX]; |
| 1662 | break; |
| 1663 | case 0xa4 ... 0xa5: /* movs */ |
| 1664 | c->dst.type = OP_MEM; |
| 1665 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1666 | c->dst.ptr = (unsigned long *)register_address(c, |
| 1667 | es_base(ctxt), |
| 1668 | c->regs[VCPU_REGS_RDI]); |
| 1669 | if ((rc = ops->read_emulated(register_address(c, |
| 1670 | seg_override_base(ctxt, c), |
| 1671 | c->regs[VCPU_REGS_RSI]), |
| 1672 | &c->dst.val, |
| 1673 | c->dst.bytes, ctxt->vcpu)) != 0) |
| 1674 | goto done; |
| 1675 | register_address_increment(c, &c->regs[VCPU_REGS_RSI], |
| 1676 | (ctxt->eflags & EFLG_DF) ? -c->dst.bytes |
| 1677 | : c->dst.bytes); |
| 1678 | register_address_increment(c, &c->regs[VCPU_REGS_RDI], |
| 1679 | (ctxt->eflags & EFLG_DF) ? -c->dst.bytes |
| 1680 | : c->dst.bytes); |
| 1681 | break; |
| 1682 | case 0xa6 ... 0xa7: /* cmps */ |
| 1683 | c->src.type = OP_NONE; /* Disable writeback. */ |
| 1684 | c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1685 | c->src.ptr = (unsigned long *)register_address(c, |
| 1686 | seg_override_base(ctxt, c), |
| 1687 | c->regs[VCPU_REGS_RSI]); |
| 1688 | if ((rc = ops->read_emulated((unsigned long)c->src.ptr, |
| 1689 | &c->src.val, |
| 1690 | c->src.bytes, |
| 1691 | ctxt->vcpu)) != 0) |
| 1692 | goto done; |
| 1693 | |
| 1694 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1695 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1696 | c->dst.ptr = (unsigned long *)register_address(c, |
| 1697 | es_base(ctxt), |
| 1698 | c->regs[VCPU_REGS_RDI]); |
| 1699 | if ((rc = ops->read_emulated((unsigned long)c->dst.ptr, |
| 1700 | &c->dst.val, |
| 1701 | c->dst.bytes, |
| 1702 | ctxt->vcpu)) != 0) |
| 1703 | goto done; |
| 1704 | |
| 1705 | DPRINTF("cmps: mem1=0x%p mem2=0x%p\n", c->src.ptr, c->dst.ptr); |
| 1706 | |
| 1707 | emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags); |
| 1708 | |
| 1709 | register_address_increment(c, &c->regs[VCPU_REGS_RSI], |
| 1710 | (ctxt->eflags & EFLG_DF) ? -c->src.bytes |
| 1711 | : c->src.bytes); |
| 1712 | register_address_increment(c, &c->regs[VCPU_REGS_RDI], |
| 1713 | (ctxt->eflags & EFLG_DF) ? -c->dst.bytes |
| 1714 | : c->dst.bytes); |
| 1715 | |
| 1716 | break; |
| 1717 | case 0xaa ... 0xab: /* stos */ |
| 1718 | c->dst.type = OP_MEM; |
| 1719 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1720 | c->dst.ptr = (unsigned long *)register_address(c, |
| 1721 | es_base(ctxt), |
| 1722 | c->regs[VCPU_REGS_RDI]); |
| 1723 | c->dst.val = c->regs[VCPU_REGS_RAX]; |
| 1724 | register_address_increment(c, &c->regs[VCPU_REGS_RDI], |
| 1725 | (ctxt->eflags & EFLG_DF) ? -c->dst.bytes |
| 1726 | : c->dst.bytes); |
| 1727 | break; |
| 1728 | case 0xac ... 0xad: /* lods */ |
| 1729 | c->dst.type = OP_REG; |
| 1730 | c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; |
| 1731 | c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX]; |
| 1732 | if ((rc = ops->read_emulated(register_address(c, |
| 1733 | seg_override_base(ctxt, c), |
| 1734 | c->regs[VCPU_REGS_RSI]), |
| 1735 | &c->dst.val, |
| 1736 | c->dst.bytes, |
| 1737 | ctxt->vcpu)) != 0) |
| 1738 | goto done; |
| 1739 | register_address_increment(c, &c->regs[VCPU_REGS_RSI], |
| 1740 | (ctxt->eflags & EFLG_DF) ? -c->dst.bytes |
| 1741 | : c->dst.bytes); |
| 1742 | break; |
| 1743 | case 0xae ... 0xaf: /* scas */ |
| 1744 | DPRINTF("Urk! I don't handle SCAS.\n"); |
| 1745 | goto cannot_emulate; |
| 1746 | case 0xb0 ... 0xbf: /* mov r, imm */ |
| 1747 | goto mov; |
| 1748 | case 0xc0 ... 0xc1: |
| 1749 | emulate_grp2(ctxt); |
| 1750 | break; |
| 1751 | case 0xc3: /* ret */ |
| 1752 | c->dst.type = OP_REG; |
| 1753 | c->dst.ptr = &c->eip; |
| 1754 | c->dst.bytes = c->op_bytes; |
| 1755 | goto pop_instruction; |
| 1756 | case 0xc6 ... 0xc7: /* mov (sole member of Grp11) */ |
| 1757 | mov: |
| 1758 | c->dst.val = c->src.val; |
| 1759 | break; |
| 1760 | case 0xcb: /* ret far */ |
| 1761 | rc = emulate_ret_far(ctxt, ops); |
| 1762 | if (rc) |
| 1763 | goto done; |
| 1764 | break; |
| 1765 | case 0xd0 ... 0xd1: /* Grp2 */ |
| 1766 | c->src.val = 1; |
| 1767 | emulate_grp2(ctxt); |
| 1768 | break; |
| 1769 | case 0xd2 ... 0xd3: /* Grp2 */ |
| 1770 | c->src.val = c->regs[VCPU_REGS_RCX]; |
| 1771 | emulate_grp2(ctxt); |
| 1772 | break; |
| 1773 | case 0xe4: /* inb */ |
| 1774 | case 0xe5: /* in */ |
| 1775 | port = insn_fetch(u8, 1, c->eip); |
| 1776 | io_dir_in = 1; |
| 1777 | goto do_io; |
| 1778 | case 0xe6: /* outb */ |
| 1779 | case 0xe7: /* out */ |
| 1780 | port = insn_fetch(u8, 1, c->eip); |
| 1781 | io_dir_in = 0; |
| 1782 | goto do_io; |
| 1783 | case 0xe8: /* call (near) */ { |
| 1784 | long int rel = c->src.val; |
| 1785 | c->src.val = (unsigned long) c->eip; |
| 1786 | jmp_rel(c, rel); |
| 1787 | emulate_push(ctxt); |
| 1788 | break; |
| 1789 | } |
| 1790 | case 0xe9: /* jmp rel */ |
| 1791 | goto jmp; |
| 1792 | case 0xea: /* jmp far */ |
| 1793 | if (kvm_load_segment_descriptor(ctxt->vcpu, c->src2.val, 9, |
| 1794 | VCPU_SREG_CS) < 0) { |
| 1795 | DPRINTF("jmp far: Failed to load CS descriptor\n"); |
| 1796 | goto cannot_emulate; |
| 1797 | } |
| 1798 | |
| 1799 | c->eip = c->src.val; |
| 1800 | break; |
| 1801 | case 0xeb: |
| 1802 | jmp: /* jmp rel short */ |
| 1803 | jmp_rel(c, c->src.val); |
| 1804 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1805 | break; |
| 1806 | case 0xec: /* in al,dx */ |
| 1807 | case 0xed: /* in (e/r)ax,dx */ |
| 1808 | port = c->regs[VCPU_REGS_RDX]; |
| 1809 | io_dir_in = 1; |
| 1810 | goto do_io; |
| 1811 | case 0xee: /* out al,dx */ |
| 1812 | case 0xef: /* out (e/r)ax,dx */ |
| 1813 | port = c->regs[VCPU_REGS_RDX]; |
| 1814 | io_dir_in = 0; |
| 1815 | do_io: if (kvm_emulate_pio(ctxt->vcpu, NULL, io_dir_in, |
| 1816 | (c->d & ByteOp) ? 1 : c->op_bytes, |
| 1817 | port) != 0) { |
| 1818 | c->eip = saved_eip; |
| 1819 | goto cannot_emulate; |
| 1820 | } |
| 1821 | break; |
| 1822 | case 0xf4: /* hlt */ |
| 1823 | ctxt->vcpu->arch.halt_request = 1; |
| 1824 | break; |
| 1825 | case 0xf5: /* cmc */ |
| 1826 | /* complement carry flag from eflags reg */ |
| 1827 | ctxt->eflags ^= EFLG_CF; |
| 1828 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1829 | break; |
| 1830 | case 0xf6 ... 0xf7: /* Grp3 */ |
| 1831 | rc = emulate_grp3(ctxt, ops); |
| 1832 | if (rc != 0) |
| 1833 | goto done; |
| 1834 | break; |
| 1835 | case 0xf8: /* clc */ |
| 1836 | ctxt->eflags &= ~EFLG_CF; |
| 1837 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1838 | break; |
| 1839 | case 0xfa: /* cli */ |
| 1840 | ctxt->eflags &= ~X86_EFLAGS_IF; |
| 1841 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1842 | break; |
| 1843 | case 0xfb: /* sti */ |
| 1844 | ctxt->eflags |= X86_EFLAGS_IF; |
| 1845 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1846 | break; |
| 1847 | case 0xfc: /* cld */ |
| 1848 | ctxt->eflags &= ~EFLG_DF; |
| 1849 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1850 | break; |
| 1851 | case 0xfd: /* std */ |
| 1852 | ctxt->eflags |= EFLG_DF; |
| 1853 | c->dst.type = OP_NONE; /* Disable writeback. */ |
| 1854 | break; |
| 1855 | case 0xfe ... 0xff: /* Grp4/Grp5 */ |
| 1856 | rc = emulate_grp45(ctxt, ops); |
| 1857 | if (rc != 0) |
| 1858 | goto done; |
| 1859 | break; |
| 1860 | } |
| 1861 | |
| 1862 | writeback: |
| 1863 | rc = writeback(ctxt, ops); |
| 1864 | if (rc != 0) |
| 1865 | goto done; |
| 1866 | |
| 1867 | /* Commit shadow register state. */ |
| 1868 | memcpy(ctxt->vcpu->arch.regs, c->regs, sizeof c->regs); |
| 1869 | kvm_rip_write(ctxt->vcpu, c->eip); |
| 1870 | |
| 1871 | done: |
| 1872 | if (rc == X86EMUL_UNHANDLEABLE) { |
| 1873 | c->eip = saved_eip; |
| 1874 | return -1; |
| 1875 | } |
| 1876 | return 0; |
| 1877 | |
| 1878 | twobyte_insn: |
| 1879 | switch (c->b) { |
| 1880 | case 0x01: /* lgdt, lidt, lmsw */ |
| 1881 | switch (c->modrm_reg) { |
| 1882 | u16 size; |
| 1883 | unsigned long address; |
| 1884 | |
| 1885 | case 0: /* vmcall */ |
| 1886 | if (c->modrm_mod != 3 || c->modrm_rm != 1) |
| 1887 | goto cannot_emulate; |
| 1888 | |
| 1889 | rc = kvm_fix_hypercall(ctxt->vcpu); |
| 1890 | if (rc) |
| 1891 | goto done; |
| 1892 | |
| 1893 | /* Let the processor re-execute the fixed hypercall */ |
| 1894 | c->eip = kvm_rip_read(ctxt->vcpu); |
| 1895 | /* Disable writeback. */ |
| 1896 | c->dst.type = OP_NONE; |
| 1897 | break; |
| 1898 | case 2: /* lgdt */ |
| 1899 | rc = read_descriptor(ctxt, ops, c->src.ptr, |
| 1900 | &size, &address, c->op_bytes); |
| 1901 | if (rc) |
| 1902 | goto done; |
| 1903 | realmode_lgdt(ctxt->vcpu, size, address); |
| 1904 | /* Disable writeback. */ |
| 1905 | c->dst.type = OP_NONE; |
| 1906 | break; |
| 1907 | case 3: /* lidt/vmmcall */ |
| 1908 | if (c->modrm_mod == 3) { |
| 1909 | switch (c->modrm_rm) { |
| 1910 | case 1: |
| 1911 | rc = kvm_fix_hypercall(ctxt->vcpu); |
| 1912 | if (rc) |
| 1913 | goto done; |
| 1914 | break; |
| 1915 | default: |
| 1916 | goto cannot_emulate; |
| 1917 | } |
| 1918 | } else { |
| 1919 | rc = read_descriptor(ctxt, ops, c->src.ptr, |
| 1920 | &size, &address, |
| 1921 | c->op_bytes); |
| 1922 | if (rc) |
| 1923 | goto done; |
| 1924 | realmode_lidt(ctxt->vcpu, size, address); |
| 1925 | } |
| 1926 | /* Disable writeback. */ |
| 1927 | c->dst.type = OP_NONE; |
| 1928 | break; |
| 1929 | case 4: /* smsw */ |
| 1930 | c->dst.bytes = 2; |
| 1931 | c->dst.val = realmode_get_cr(ctxt->vcpu, 0); |
| 1932 | break; |
| 1933 | case 6: /* lmsw */ |
| 1934 | realmode_lmsw(ctxt->vcpu, (u16)c->src.val, |
| 1935 | &ctxt->eflags); |
| 1936 | c->dst.type = OP_NONE; |
| 1937 | break; |
| 1938 | case 7: /* invlpg*/ |
| 1939 | emulate_invlpg(ctxt->vcpu, memop); |
| 1940 | /* Disable writeback. */ |
| 1941 | c->dst.type = OP_NONE; |
| 1942 | break; |
| 1943 | default: |
| 1944 | goto cannot_emulate; |
| 1945 | } |
| 1946 | break; |
| 1947 | case 0x06: |
| 1948 | emulate_clts(ctxt->vcpu); |
| 1949 | c->dst.type = OP_NONE; |
| 1950 | break; |
| 1951 | case 0x08: /* invd */ |
| 1952 | case 0x09: /* wbinvd */ |
| 1953 | case 0x0d: /* GrpP (prefetch) */ |
| 1954 | case 0x18: /* Grp16 (prefetch/nop) */ |
| 1955 | c->dst.type = OP_NONE; |
| 1956 | break; |
| 1957 | case 0x20: /* mov cr, reg */ |
| 1958 | if (c->modrm_mod != 3) |
| 1959 | goto cannot_emulate; |
| 1960 | c->regs[c->modrm_rm] = |
| 1961 | realmode_get_cr(ctxt->vcpu, c->modrm_reg); |
| 1962 | c->dst.type = OP_NONE; /* no writeback */ |
| 1963 | break; |
| 1964 | case 0x21: /* mov from dr to reg */ |
| 1965 | if (c->modrm_mod != 3) |
| 1966 | goto cannot_emulate; |
| 1967 | rc = emulator_get_dr(ctxt, c->modrm_reg, &c->regs[c->modrm_rm]); |
| 1968 | if (rc) |
| 1969 | goto cannot_emulate; |
| 1970 | c->dst.type = OP_NONE; /* no writeback */ |
| 1971 | break; |
| 1972 | case 0x22: /* mov reg, cr */ |
| 1973 | if (c->modrm_mod != 3) |
| 1974 | goto cannot_emulate; |
| 1975 | realmode_set_cr(ctxt->vcpu, |
| 1976 | c->modrm_reg, c->modrm_val, &ctxt->eflags); |
| 1977 | c->dst.type = OP_NONE; |
| 1978 | break; |
| 1979 | case 0x23: /* mov from reg to dr */ |
| 1980 | if (c->modrm_mod != 3) |
| 1981 | goto cannot_emulate; |
| 1982 | rc = emulator_set_dr(ctxt, c->modrm_reg, |
| 1983 | c->regs[c->modrm_rm]); |
| 1984 | if (rc) |
| 1985 | goto cannot_emulate; |
| 1986 | c->dst.type = OP_NONE; /* no writeback */ |
| 1987 | break; |
| 1988 | case 0x30: |
| 1989 | /* wrmsr */ |
| 1990 | msr_data = (u32)c->regs[VCPU_REGS_RAX] |
| 1991 | | ((u64)c->regs[VCPU_REGS_RDX] << 32); |
| 1992 | rc = kvm_set_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], msr_data); |
| 1993 | if (rc) { |
| 1994 | kvm_inject_gp(ctxt->vcpu, 0); |
| 1995 | c->eip = kvm_rip_read(ctxt->vcpu); |
| 1996 | } |
| 1997 | rc = X86EMUL_CONTINUE; |
| 1998 | c->dst.type = OP_NONE; |
| 1999 | break; |
| 2000 | case 0x32: |
| 2001 | /* rdmsr */ |
| 2002 | rc = kvm_get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data); |
| 2003 | if (rc) { |
| 2004 | kvm_inject_gp(ctxt->vcpu, 0); |
| 2005 | c->eip = kvm_rip_read(ctxt->vcpu); |
| 2006 | } else { |
| 2007 | c->regs[VCPU_REGS_RAX] = (u32)msr_data; |
| 2008 | c->regs[VCPU_REGS_RDX] = msr_data >> 32; |
| 2009 | } |
| 2010 | rc = X86EMUL_CONTINUE; |
| 2011 | c->dst.type = OP_NONE; |
| 2012 | break; |
| 2013 | case 0x40 ... 0x4f: /* cmov */ |
| 2014 | c->dst.val = c->dst.orig_val = c->src.val; |
| 2015 | if (!test_cc(c->b, ctxt->eflags)) |
| 2016 | c->dst.type = OP_NONE; /* no writeback */ |
| 2017 | break; |
| 2018 | case 0x80 ... 0x8f: /* jnz rel, etc*/ |
| 2019 | if (test_cc(c->b, ctxt->eflags)) |
| 2020 | jmp_rel(c, c->src.val); |
| 2021 | c->dst.type = OP_NONE; |
| 2022 | break; |
| 2023 | case 0xa3: |
| 2024 | bt: /* bt */ |
| 2025 | c->dst.type = OP_NONE; |
| 2026 | /* only subword offset */ |
| 2027 | c->src.val &= (c->dst.bytes << 3) - 1; |
| 2028 | emulate_2op_SrcV_nobyte("bt", c->src, c->dst, ctxt->eflags); |
| 2029 | break; |
| 2030 | case 0xa4: /* shld imm8, r, r/m */ |
| 2031 | case 0xa5: /* shld cl, r, r/m */ |
| 2032 | emulate_2op_cl("shld", c->src2, c->src, c->dst, ctxt->eflags); |
| 2033 | break; |
| 2034 | case 0xab: |
| 2035 | bts: /* bts */ |
| 2036 | /* only subword offset */ |
| 2037 | c->src.val &= (c->dst.bytes << 3) - 1; |
| 2038 | emulate_2op_SrcV_nobyte("bts", c->src, c->dst, ctxt->eflags); |
| 2039 | break; |
| 2040 | case 0xac: /* shrd imm8, r, r/m */ |
| 2041 | case 0xad: /* shrd cl, r, r/m */ |
| 2042 | emulate_2op_cl("shrd", c->src2, c->src, c->dst, ctxt->eflags); |
| 2043 | break; |
| 2044 | case 0xae: /* clflush */ |
| 2045 | break; |
| 2046 | case 0xb0 ... 0xb1: /* cmpxchg */ |
| 2047 | /* |
| 2048 | * Save real source value, then compare EAX against |
| 2049 | * destination. |
| 2050 | */ |
| 2051 | c->src.orig_val = c->src.val; |
| 2052 | c->src.val = c->regs[VCPU_REGS_RAX]; |
| 2053 | emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags); |
| 2054 | if (ctxt->eflags & EFLG_ZF) { |
| 2055 | /* Success: write back to memory. */ |
| 2056 | c->dst.val = c->src.orig_val; |
| 2057 | } else { |
| 2058 | /* Failure: write the value we saw to EAX. */ |
| 2059 | c->dst.type = OP_REG; |
| 2060 | c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX]; |
| 2061 | } |
| 2062 | break; |
| 2063 | case 0xb3: |
| 2064 | btr: /* btr */ |
| 2065 | /* only subword offset */ |
| 2066 | c->src.val &= (c->dst.bytes << 3) - 1; |
| 2067 | emulate_2op_SrcV_nobyte("btr", c->src, c->dst, ctxt->eflags); |
| 2068 | break; |
| 2069 | case 0xb6 ... 0xb7: /* movzx */ |
| 2070 | c->dst.bytes = c->op_bytes; |
| 2071 | c->dst.val = (c->d & ByteOp) ? (u8) c->src.val |
| 2072 | : (u16) c->src.val; |
| 2073 | break; |
| 2074 | case 0xba: /* Grp8 */ |
| 2075 | switch (c->modrm_reg & 3) { |
| 2076 | case 0: |
| 2077 | goto bt; |
| 2078 | case 1: |
| 2079 | goto bts; |
| 2080 | case 2: |
| 2081 | goto btr; |
| 2082 | case 3: |
| 2083 | goto btc; |
| 2084 | } |
| 2085 | break; |
| 2086 | case 0xbb: |
| 2087 | btc: /* btc */ |
| 2088 | /* only subword offset */ |
| 2089 | c->src.val &= (c->dst.bytes << 3) - 1; |
| 2090 | emulate_2op_SrcV_nobyte("btc", c->src, c->dst, ctxt->eflags); |
| 2091 | break; |
| 2092 | case 0xbe ... 0xbf: /* movsx */ |
| 2093 | c->dst.bytes = c->op_bytes; |
| 2094 | c->dst.val = (c->d & ByteOp) ? (s8) c->src.val : |
| 2095 | (s16) c->src.val; |
| 2096 | break; |
| 2097 | case 0xc3: /* movnti */ |
| 2098 | c->dst.bytes = c->op_bytes; |
| 2099 | c->dst.val = (c->op_bytes == 4) ? (u32) c->src.val : |
| 2100 | (u64) c->src.val; |
| 2101 | break; |
| 2102 | case 0xc7: /* Grp9 (cmpxchg8b) */ |
| 2103 | rc = emulate_grp9(ctxt, ops, memop); |
| 2104 | if (rc != 0) |
| 2105 | goto done; |
| 2106 | c->dst.type = OP_NONE; |
| 2107 | break; |
| 2108 | } |
| 2109 | goto writeback; |
| 2110 | |
| 2111 | cannot_emulate: |
| 2112 | DPRINTF("Cannot emulate %02x\n", c->b); |
| 2113 | c->eip = saved_eip; |
| 2114 | return -1; |
| 2115 | } |