1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Disassemble s390 instructions. 4 * 5 * Copyright IBM Corp. 2007 6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), 7 */ 8 9 #include <linux/sched.h> 10 #include <linux/kernel.h> 11 #include <linux/string.h> 12 #include <linux/errno.h> 13 #include <linux/ptrace.h> 14 #include <linux/timer.h> 15 #include <linux/mm.h> 16 #include <linux/smp.h> 17 #include <linux/init.h> 18 #include <linux/interrupt.h> 19 #include <linux/delay.h> 20 #include <linux/export.h> 21 #include <linux/kallsyms.h> 22 #include <linux/reboot.h> 23 #include <linux/kprobes.h> 24 #include <linux/kdebug.h> 25 #include <linux/uaccess.h> 26 #include <linux/atomic.h> 27 #include <asm/dis.h> 28 #include <asm/io.h> 29 #include <asm/cpcmd.h> 30 #include <asm/lowcore.h> 31 #include <asm/debug.h> 32 #include <asm/irq.h> 33 34 /* Type of operand */ 35 #define OPERAND_GPR 0x1 /* Operand printed as %rx */ 36 #define OPERAND_FPR 0x2 /* Operand printed as %fx */ 37 #define OPERAND_AR 0x4 /* Operand printed as %ax */ 38 #define OPERAND_CR 0x8 /* Operand printed as %cx */ 39 #define OPERAND_VR 0x10 /* Operand printed as %vx */ 40 #define OPERAND_DISP 0x20 /* Operand printed as displacement */ 41 #define OPERAND_BASE 0x40 /* Operand printed as base register */ 42 #define OPERAND_INDEX 0x80 /* Operand printed as index register */ 43 #define OPERAND_PCREL 0x100 /* Operand printed as pc-relative symbol */ 44 #define OPERAND_SIGNED 0x200 /* Operand printed as signed value */ 45 #define OPERAND_LENGTH 0x400 /* Operand printed as length (+1) */ 46 47 struct s390_operand { 48 unsigned char bits; /* The number of bits in the operand. */ 49 unsigned char shift; /* The number of bits to shift. */ 50 unsigned short flags; /* One bit syntax flags. */ 51 }; 52 53 struct s390_insn { 54 union { 55 const char name[5]; 56 struct { 57 unsigned char zero; 58 unsigned int offset; 59 } __packed; 60 }; 61 unsigned char opfrag; 62 unsigned char format; 63 }; 64 65 struct s390_opcode_offset { 66 unsigned char opcode; 67 unsigned char mask; 68 unsigned char byte; 69 unsigned short offset; 70 unsigned short count; 71 } __packed; 72 73 enum { 74 UNUSED, 75 A_8, /* Access reg. starting at position 8 */ 76 A_12, /* Access reg. starting at position 12 */ 77 A_24, /* Access reg. starting at position 24 */ 78 A_28, /* Access reg. starting at position 28 */ 79 B_16, /* Base register starting at position 16 */ 80 B_32, /* Base register starting at position 32 */ 81 C_8, /* Control reg. starting at position 8 */ 82 C_12, /* Control reg. starting at position 12 */ 83 D20_20, /* 20 bit displacement starting at 20 */ 84 D_20, /* Displacement starting at position 20 */ 85 D_36, /* Displacement starting at position 36 */ 86 F_8, /* FPR starting at position 8 */ 87 F_12, /* FPR starting at position 12 */ 88 F_16, /* FPR starting at position 16 */ 89 F_24, /* FPR starting at position 24 */ 90 F_28, /* FPR starting at position 28 */ 91 F_32, /* FPR starting at position 32 */ 92 I8_8, /* 8 bit signed value starting at 8 */ 93 I8_32, /* 8 bit signed value starting at 32 */ 94 I16_16, /* 16 bit signed value starting at 16 */ 95 I16_32, /* 16 bit signed value starting at 32 */ 96 I32_16, /* 32 bit signed value starting at 16 */ 97 J12_12, /* 12 bit PC relative offset at 12 */ 98 J16_16, /* 16 bit PC relative offset at 16 */ 99 J16_32, /* 16 bit PC relative offset at 32 */ 100 J24_24, /* 24 bit PC relative offset at 24 */ 101 J32_16, /* 32 bit PC relative offset at 16 */ 102 L4_8, /* 4 bit length starting at position 8 */ 103 L4_12, /* 4 bit length starting at position 12 */ 104 L8_8, /* 8 bit length starting at position 8 */ 105 R_8, /* GPR starting at position 8 */ 106 R_12, /* GPR starting at position 12 */ 107 R_16, /* GPR starting at position 16 */ 108 R_24, /* GPR starting at position 24 */ 109 R_28, /* GPR starting at position 28 */ 110 U4_8, /* 4 bit unsigned value starting at 8 */ 111 U4_12, /* 4 bit unsigned value starting at 12 */ 112 U4_16, /* 4 bit unsigned value starting at 16 */ 113 U4_20, /* 4 bit unsigned value starting at 20 */ 114 U4_24, /* 4 bit unsigned value starting at 24 */ 115 U4_28, /* 4 bit unsigned value starting at 28 */ 116 U4_32, /* 4 bit unsigned value starting at 32 */ 117 U4_36, /* 4 bit unsigned value starting at 36 */ 118 U8_8, /* 8 bit unsigned value starting at 8 */ 119 U8_16, /* 8 bit unsigned value starting at 16 */ 120 U8_24, /* 8 bit unsigned value starting at 24 */ 121 U8_28, /* 8 bit unsigned value starting at 28 */ 122 U8_32, /* 8 bit unsigned value starting at 32 */ 123 U12_16, /* 12 bit unsigned value starting at 16 */ 124 U16_16, /* 16 bit unsigned value starting at 16 */ 125 U16_32, /* 16 bit unsigned value starting at 32 */ 126 U32_16, /* 32 bit unsigned value starting at 16 */ 127 VX_12, /* Vector index register starting at position 12 */ 128 V_8, /* Vector reg. starting at position 8 */ 129 V_12, /* Vector reg. starting at position 12 */ 130 V_16, /* Vector reg. starting at position 16 */ 131 V_32, /* Vector reg. starting at position 32 */ 132 X_12, /* Index register starting at position 12 */ 133 }; 134 135 static const struct s390_operand operands[] = { 136 [UNUSED] = { 0, 0, 0 }, 137 [A_8] = { 4, 8, OPERAND_AR }, 138 [A_12] = { 4, 12, OPERAND_AR }, 139 [A_24] = { 4, 24, OPERAND_AR }, 140 [A_28] = { 4, 28, OPERAND_AR }, 141 [B_16] = { 4, 16, OPERAND_BASE | OPERAND_GPR }, 142 [B_32] = { 4, 32, OPERAND_BASE | OPERAND_GPR }, 143 [C_8] = { 4, 8, OPERAND_CR }, 144 [C_12] = { 4, 12, OPERAND_CR }, 145 [D20_20] = { 20, 20, OPERAND_DISP | OPERAND_SIGNED }, 146 [D_20] = { 12, 20, OPERAND_DISP }, 147 [D_36] = { 12, 36, OPERAND_DISP }, 148 [F_8] = { 4, 8, OPERAND_FPR }, 149 [F_12] = { 4, 12, OPERAND_FPR }, 150 [F_16] = { 4, 16, OPERAND_FPR }, 151 [F_24] = { 4, 24, OPERAND_FPR }, 152 [F_28] = { 4, 28, OPERAND_FPR }, 153 [F_32] = { 4, 32, OPERAND_FPR }, 154 [I8_8] = { 8, 8, OPERAND_SIGNED }, 155 [I8_32] = { 8, 32, OPERAND_SIGNED }, 156 [I16_16] = { 16, 16, OPERAND_SIGNED }, 157 [I16_32] = { 16, 32, OPERAND_SIGNED }, 158 [I32_16] = { 32, 16, OPERAND_SIGNED }, 159 [J12_12] = { 12, 12, OPERAND_PCREL }, 160 [J16_16] = { 16, 16, OPERAND_PCREL }, 161 [J16_32] = { 16, 32, OPERAND_PCREL }, 162 [J24_24] = { 24, 24, OPERAND_PCREL }, 163 [J32_16] = { 32, 16, OPERAND_PCREL }, 164 [L4_8] = { 4, 8, OPERAND_LENGTH }, 165 [L4_12] = { 4, 12, OPERAND_LENGTH }, 166 [L8_8] = { 8, 8, OPERAND_LENGTH }, 167 [R_8] = { 4, 8, OPERAND_GPR }, 168 [R_12] = { 4, 12, OPERAND_GPR }, 169 [R_16] = { 4, 16, OPERAND_GPR }, 170 [R_24] = { 4, 24, OPERAND_GPR }, 171 [R_28] = { 4, 28, OPERAND_GPR }, 172 [U4_8] = { 4, 8, 0 }, 173 [U4_12] = { 4, 12, 0 }, 174 [U4_16] = { 4, 16, 0 }, 175 [U4_20] = { 4, 20, 0 }, 176 [U4_24] = { 4, 24, 0 }, 177 [U4_28] = { 4, 28, 0 }, 178 [U4_32] = { 4, 32, 0 }, 179 [U4_36] = { 4, 36, 0 }, 180 [U8_8] = { 8, 8, 0 }, 181 [U8_16] = { 8, 16, 0 }, 182 [U8_24] = { 8, 24, 0 }, 183 [U8_28] = { 8, 28, 0 }, 184 [U8_32] = { 8, 32, 0 }, 185 [U12_16] = { 12, 16, 0 }, 186 [U16_16] = { 16, 16, 0 }, 187 [U16_32] = { 16, 32, 0 }, 188 [U32_16] = { 32, 16, 0 }, 189 [VX_12] = { 4, 12, OPERAND_INDEX | OPERAND_VR }, 190 [V_8] = { 4, 8, OPERAND_VR }, 191 [V_12] = { 4, 12, OPERAND_VR }, 192 [V_16] = { 4, 16, OPERAND_VR }, 193 [V_32] = { 4, 32, OPERAND_VR }, 194 [X_12] = { 4, 12, OPERAND_INDEX | OPERAND_GPR }, 195 }; 196 197 static const unsigned char formats[][6] = { 198 [INSTR_E] = { 0, 0, 0, 0, 0, 0 }, 199 [INSTR_IE_UU] = { U4_24, U4_28, 0, 0, 0, 0 }, 200 [INSTR_MII_UPP] = { U4_8, J12_12, J24_24 }, 201 [INSTR_RIE_R0IU] = { R_8, I16_16, U4_32, 0, 0, 0 }, 202 [INSTR_RIE_R0UU] = { R_8, U16_16, U4_32, 0, 0, 0 }, 203 [INSTR_RIE_RRI0] = { R_8, R_12, I16_16, 0, 0, 0 }, 204 [INSTR_RIE_RRP] = { R_8, R_12, J16_16, 0, 0, 0 }, 205 [INSTR_RIE_RRPU] = { R_8, R_12, U4_32, J16_16, 0, 0 }, 206 [INSTR_RIE_RRUUU] = { R_8, R_12, U8_16, U8_24, U8_32, 0 }, 207 [INSTR_RIE_RUI0] = { R_8, I16_16, U4_12, 0, 0, 0 }, 208 [INSTR_RIE_RUPI] = { R_8, I8_32, U4_12, J16_16, 0, 0 }, 209 [INSTR_RIE_RUPU] = { R_8, U8_32, U4_12, J16_16, 0, 0 }, 210 [INSTR_RIL_RI] = { R_8, I32_16, 0, 0, 0, 0 }, 211 [INSTR_RIL_RP] = { R_8, J32_16, 0, 0, 0, 0 }, 212 [INSTR_RIL_RU] = { R_8, U32_16, 0, 0, 0, 0 }, 213 [INSTR_RIL_UP] = { U4_8, J32_16, 0, 0, 0, 0 }, 214 [INSTR_RIS_RURDI] = { R_8, I8_32, U4_12, D_20, B_16, 0 }, 215 [INSTR_RIS_RURDU] = { R_8, U8_32, U4_12, D_20, B_16, 0 }, 216 [INSTR_RI_RI] = { R_8, I16_16, 0, 0, 0, 0 }, 217 [INSTR_RI_RP] = { R_8, J16_16, 0, 0, 0, 0 }, 218 [INSTR_RI_RU] = { R_8, U16_16, 0, 0, 0, 0 }, 219 [INSTR_RI_UP] = { U4_8, J16_16, 0, 0, 0, 0 }, 220 [INSTR_RRE_00] = { 0, 0, 0, 0, 0, 0 }, 221 [INSTR_RRE_AA] = { A_24, A_28, 0, 0, 0, 0 }, 222 [INSTR_RRE_AR] = { A_24, R_28, 0, 0, 0, 0 }, 223 [INSTR_RRE_F0] = { F_24, 0, 0, 0, 0, 0 }, 224 [INSTR_RRE_FF] = { F_24, F_28, 0, 0, 0, 0 }, 225 [INSTR_RRE_FR] = { F_24, R_28, 0, 0, 0, 0 }, 226 [INSTR_RRE_R0] = { R_24, 0, 0, 0, 0, 0 }, 227 [INSTR_RRE_RA] = { R_24, A_28, 0, 0, 0, 0 }, 228 [INSTR_RRE_RF] = { R_24, F_28, 0, 0, 0, 0 }, 229 [INSTR_RRE_RR] = { R_24, R_28, 0, 0, 0, 0 }, 230 [INSTR_RRF_0UFF] = { F_24, F_28, U4_20, 0, 0, 0 }, 231 [INSTR_RRF_0URF] = { R_24, F_28, U4_20, 0, 0, 0 }, 232 [INSTR_RRF_F0FF] = { F_16, F_24, F_28, 0, 0, 0 }, 233 [INSTR_RRF_F0FF2] = { F_24, F_16, F_28, 0, 0, 0 }, 234 [INSTR_RRF_F0FR] = { F_24, F_16, R_28, 0, 0, 0 }, 235 [INSTR_RRF_FFRU] = { F_24, F_16, R_28, U4_20, 0, 0 }, 236 [INSTR_RRF_FUFF] = { F_24, F_16, F_28, U4_20, 0, 0 }, 237 [INSTR_RRF_FUFF2] = { F_24, F_28, F_16, U4_20, 0, 0 }, 238 [INSTR_RRF_R0RR] = { R_24, R_16, R_28, 0, 0, 0 }, 239 [INSTR_RRF_R0RR2] = { R_24, R_28, R_16, 0, 0, 0 }, 240 [INSTR_RRF_RURR] = { R_24, R_28, R_16, U4_20, 0, 0 }, 241 [INSTR_RRF_RURR2] = { R_24, R_16, R_28, U4_20, 0, 0 }, 242 [INSTR_RRF_U0FF] = { F_24, U4_16, F_28, 0, 0, 0 }, 243 [INSTR_RRF_U0RF] = { R_24, U4_16, F_28, 0, 0, 0 }, 244 [INSTR_RRF_U0RR] = { R_24, R_28, U4_16, 0, 0, 0 }, 245 [INSTR_RRF_URR] = { R_24, R_28, U8_16, 0, 0, 0 }, 246 [INSTR_RRF_UUFF] = { F_24, U4_16, F_28, U4_20, 0, 0 }, 247 [INSTR_RRF_UUFR] = { F_24, U4_16, R_28, U4_20, 0, 0 }, 248 [INSTR_RRF_UURF] = { R_24, U4_16, F_28, U4_20, 0, 0 }, 249 [INSTR_RRS_RRRDU] = { R_8, R_12, U4_32, D_20, B_16 }, 250 [INSTR_RR_FF] = { F_8, F_12, 0, 0, 0, 0 }, 251 [INSTR_RR_R0] = { R_8, 0, 0, 0, 0, 0 }, 252 [INSTR_RR_RR] = { R_8, R_12, 0, 0, 0, 0 }, 253 [INSTR_RR_U0] = { U8_8, 0, 0, 0, 0, 0 }, 254 [INSTR_RR_UR] = { U4_8, R_12, 0, 0, 0, 0 }, 255 [INSTR_RSI_RRP] = { R_8, R_12, J16_16, 0, 0, 0 }, 256 [INSTR_RSL_LRDFU] = { F_32, D_20, L8_8, B_16, U4_36, 0 }, 257 [INSTR_RSL_R0RD] = { D_20, L4_8, B_16, 0, 0, 0 }, 258 [INSTR_RSY_AARD] = { A_8, A_12, D20_20, B_16, 0, 0 }, 259 [INSTR_RSY_CCRD] = { C_8, C_12, D20_20, B_16, 0, 0 }, 260 [INSTR_RSY_RDRU] = { R_8, D20_20, B_16, U4_12, 0, 0 }, 261 [INSTR_RSY_RRRD] = { R_8, R_12, D20_20, B_16, 0, 0 }, 262 [INSTR_RSY_RURD] = { R_8, U4_12, D20_20, B_16, 0, 0 }, 263 [INSTR_RSY_RURD2] = { R_8, D20_20, B_16, U4_12, 0, 0 }, 264 [INSTR_RS_AARD] = { A_8, A_12, D_20, B_16, 0, 0 }, 265 [INSTR_RS_CCRD] = { C_8, C_12, D_20, B_16, 0, 0 }, 266 [INSTR_RS_R0RD] = { R_8, D_20, B_16, 0, 0, 0 }, 267 [INSTR_RS_RRRD] = { R_8, R_12, D_20, B_16, 0, 0 }, 268 [INSTR_RS_RURD] = { R_8, U4_12, D_20, B_16, 0, 0 }, 269 [INSTR_RXE_FRRD] = { F_8, D_20, X_12, B_16, 0, 0 }, 270 [INSTR_RXE_RRRDU] = { R_8, D_20, X_12, B_16, U4_32, 0 }, 271 [INSTR_RXF_FRRDF] = { F_32, F_8, D_20, X_12, B_16, 0 }, 272 [INSTR_RXY_FRRD] = { F_8, D20_20, X_12, B_16, 0, 0 }, 273 [INSTR_RXY_RRRD] = { R_8, D20_20, X_12, B_16, 0, 0 }, 274 [INSTR_RXY_URRD] = { U4_8, D20_20, X_12, B_16, 0, 0 }, 275 [INSTR_RX_FRRD] = { F_8, D_20, X_12, B_16, 0, 0 }, 276 [INSTR_RX_RRRD] = { R_8, D_20, X_12, B_16, 0, 0 }, 277 [INSTR_RX_URRD] = { U4_8, D_20, X_12, B_16, 0, 0 }, 278 [INSTR_SIL_RDI] = { D_20, B_16, I16_32, 0, 0, 0 }, 279 [INSTR_SIL_RDU] = { D_20, B_16, U16_32, 0, 0, 0 }, 280 [INSTR_SIY_IRD] = { D20_20, B_16, I8_8, 0, 0, 0 }, 281 [INSTR_SIY_URD] = { D20_20, B_16, U8_8, 0, 0, 0 }, 282 [INSTR_SI_RD] = { D_20, B_16, 0, 0, 0, 0 }, 283 [INSTR_SI_URD] = { D_20, B_16, U8_8, 0, 0, 0 }, 284 [INSTR_SMI_U0RDP] = { U4_8, J16_32, D_20, B_16, 0, 0 }, 285 [INSTR_SSE_RDRD] = { D_20, B_16, D_36, B_32, 0, 0 }, 286 [INSTR_SSF_RRDRD] = { D_20, B_16, D_36, B_32, R_8, 0 }, 287 [INSTR_SSF_RRDRD2] = { R_8, D_20, B_16, D_36, B_32, 0 }, 288 [INSTR_SS_L0RDRD] = { D_20, L8_8, B_16, D_36, B_32, 0 }, 289 [INSTR_SS_L2RDRD] = { D_20, B_16, D_36, L8_8, B_32, 0 }, 290 [INSTR_SS_LIRDRD] = { D_20, L4_8, B_16, D_36, B_32, U4_12 }, 291 [INSTR_SS_LLRDRD] = { D_20, L4_8, B_16, D_36, L4_12, B_32 }, 292 [INSTR_SS_RRRDRD] = { D_20, R_8, B_16, D_36, B_32, R_12 }, 293 [INSTR_SS_RRRDRD2] = { R_8, D_20, B_16, R_12, D_36, B_32 }, 294 [INSTR_SS_RRRDRD3] = { R_8, R_12, D_20, B_16, D_36, B_32 }, 295 [INSTR_S_00] = { 0, 0, 0, 0, 0, 0 }, 296 [INSTR_S_RD] = { D_20, B_16, 0, 0, 0, 0 }, 297 [INSTR_VRI_V0IU] = { V_8, I16_16, U4_32, 0, 0, 0 }, 298 [INSTR_VRI_V0U] = { V_8, U16_16, 0, 0, 0, 0 }, 299 [INSTR_VRI_V0UU2] = { V_8, U16_16, U4_32, 0, 0, 0 }, 300 [INSTR_VRI_V0UUU] = { V_8, U8_16, U8_24, U4_32, 0, 0 }, 301 [INSTR_VRI_VR0UU] = { V_8, R_12, U8_28, U4_24, 0, 0 }, 302 [INSTR_VRI_VVUU] = { V_8, V_12, U16_16, U4_32, 0, 0 }, 303 [INSTR_VRI_VVUUU] = { V_8, V_12, U12_16, U4_32, U4_28, 0 }, 304 [INSTR_VRI_VVUUU2] = { V_8, V_12, U8_28, U8_16, U4_24, 0 }, 305 [INSTR_VRI_VVV0U] = { V_8, V_12, V_16, U8_24, 0, 0 }, 306 [INSTR_VRI_VVV0UU] = { V_8, V_12, V_16, U8_24, U4_32, 0 }, 307 [INSTR_VRI_VVV0UU2] = { V_8, V_12, V_16, U8_28, U4_24, 0 }, 308 [INSTR_VRR_0V] = { V_12, 0, 0, 0, 0, 0 }, 309 [INSTR_VRR_0VV0U] = { V_12, V_16, U4_24, 0, 0, 0 }, 310 [INSTR_VRR_RV0UU] = { R_8, V_12, U4_24, U4_28, 0, 0 }, 311 [INSTR_VRR_VRR] = { V_8, R_12, R_16, 0, 0, 0 }, 312 [INSTR_VRR_VV] = { V_8, V_12, 0, 0, 0, 0 }, 313 [INSTR_VRR_VV0U] = { V_8, V_12, U4_32, 0, 0, 0 }, 314 [INSTR_VRR_VV0U0U] = { V_8, V_12, U4_32, U4_24, 0, 0 }, 315 [INSTR_VRR_VV0UU2] = { V_8, V_12, U4_32, U4_28, 0, 0 }, 316 [INSTR_VRR_VV0UUU] = { V_8, V_12, U4_32, U4_28, U4_24, 0 }, 317 [INSTR_VRR_VVV] = { V_8, V_12, V_16, 0, 0, 0 }, 318 [INSTR_VRR_VVV0U] = { V_8, V_12, V_16, U4_32, 0, 0 }, 319 [INSTR_VRR_VVV0U0U] = { V_8, V_12, V_16, U4_32, U4_24, 0 }, 320 [INSTR_VRR_VVV0UU] = { V_8, V_12, V_16, U4_32, U4_28, 0 }, 321 [INSTR_VRR_VVV0UUU] = { V_8, V_12, V_16, U4_32, U4_28, U4_24 }, 322 [INSTR_VRR_VVV0V] = { V_8, V_12, V_16, V_32, 0, 0 }, 323 [INSTR_VRR_VVVU0UV] = { V_8, V_12, V_16, V_32, U4_28, U4_20 }, 324 [INSTR_VRR_VVVU0V] = { V_8, V_12, V_16, V_32, U4_20, 0 }, 325 [INSTR_VRR_VVVUU0V] = { V_8, V_12, V_16, V_32, U4_20, U4_24 }, 326 [INSTR_VRS_RRDV] = { V_32, R_12, D_20, B_16, 0, 0 }, 327 [INSTR_VRS_RVRDU] = { R_8, V_12, D_20, B_16, U4_32, 0 }, 328 [INSTR_VRS_VRRD] = { V_8, R_12, D_20, B_16, 0, 0 }, 329 [INSTR_VRS_VRRDU] = { V_8, R_12, D_20, B_16, U4_32, 0 }, 330 [INSTR_VRS_VVRDU] = { V_8, V_12, D_20, B_16, U4_32, 0 }, 331 [INSTR_VRV_VVXRDU] = { V_8, D_20, VX_12, B_16, U4_32, 0 }, 332 [INSTR_VRX_VRRDU] = { V_8, D_20, X_12, B_16, U4_32, 0 }, 333 [INSTR_VRX_VV] = { V_8, V_12, 0, 0, 0, 0 }, 334 [INSTR_VSI_URDV] = { V_32, D_20, B_16, U8_8, 0, 0 }, 335 }; 336 337 static char long_insn_name[][7] = LONG_INSN_INITIALIZER; 338 static struct s390_insn opcode[] = OPCODE_TABLE_INITIALIZER; 339 static struct s390_opcode_offset opcode_offset[] = OPCODE_OFFSET_INITIALIZER; 340 341 /* Extracts an operand value from an instruction. */ 342 static unsigned int extract_operand(unsigned char *code, 343 const struct s390_operand *operand) 344 { 345 unsigned char *cp; 346 unsigned int val; 347 int bits; 348 349 /* Extract fragments of the operand byte for byte. */ 350 cp = code + operand->shift / 8; 351 bits = (operand->shift & 7) + operand->bits; 352 val = 0; 353 do { 354 val <<= 8; 355 val |= (unsigned int) *cp++; 356 bits -= 8; 357 } while (bits > 0); 358 val >>= -bits; 359 val &= ((1U << (operand->bits - 1)) << 1) - 1; 360 361 /* Check for special long displacement case. */ 362 if (operand->bits == 20 && operand->shift == 20) 363 val = (val & 0xff) << 12 | (val & 0xfff00) >> 8; 364 365 /* Check for register extensions bits for vector registers. */ 366 if (operand->flags & OPERAND_VR) { 367 if (operand->shift == 8) 368 val |= (code[4] & 8) << 1; 369 else if (operand->shift == 12) 370 val |= (code[4] & 4) << 2; 371 else if (operand->shift == 16) 372 val |= (code[4] & 2) << 3; 373 else if (operand->shift == 32) 374 val |= (code[4] & 1) << 4; 375 } 376 377 /* Sign extend value if the operand is signed or pc relative. */ 378 if ((operand->flags & (OPERAND_SIGNED | OPERAND_PCREL)) && 379 (val & (1U << (operand->bits - 1)))) 380 val |= (-1U << (operand->bits - 1)) << 1; 381 382 /* Double value if the operand is pc relative. */ 383 if (operand->flags & OPERAND_PCREL) 384 val <<= 1; 385 386 /* Length x in an instructions has real length x + 1. */ 387 if (operand->flags & OPERAND_LENGTH) 388 val++; 389 return val; 390 } 391 392 struct s390_insn *find_insn(unsigned char *code) 393 { 394 struct s390_opcode_offset *entry; 395 struct s390_insn *insn; 396 unsigned char opfrag; 397 int i; 398 399 /* Search the opcode offset table to find an entry which 400 * matches the beginning of the opcode. If there is no match 401 * the last entry will be used, which is the default entry for 402 * unknown instructions as well as 1-byte opcode instructions. 403 */ 404 for (i = 0; i < ARRAY_SIZE(opcode_offset); i++) { 405 entry = &opcode_offset[i]; 406 if (entry->opcode == code[0]) 407 break; 408 } 409 410 opfrag = *(code + entry->byte) & entry->mask; 411 412 insn = &opcode[entry->offset]; 413 for (i = 0; i < entry->count; i++) { 414 if (insn->opfrag == opfrag) 415 return insn; 416 insn++; 417 } 418 return NULL; 419 } 420 421 static int print_insn(char *buffer, unsigned char *code, unsigned long addr) 422 { 423 struct s390_insn *insn; 424 const unsigned char *ops; 425 const struct s390_operand *operand; 426 unsigned int value; 427 char separator; 428 char *ptr; 429 int i; 430 431 ptr = buffer; 432 insn = find_insn(code); 433 if (insn) { 434 if (insn->zero == 0) 435 ptr += sprintf(ptr, "%.7s\t", 436 long_insn_name[insn->offset]); 437 else 438 ptr += sprintf(ptr, "%.5s\t", insn->name); 439 /* Extract the operands. */ 440 separator = 0; 441 for (ops = formats[insn->format], i = 0; 442 *ops != 0 && i < 6; ops++, i++) { 443 operand = operands + *ops; 444 value = extract_operand(code, operand); 445 if ((operand->flags & OPERAND_INDEX) && value == 0) 446 continue; 447 if ((operand->flags & OPERAND_BASE) && 448 value == 0 && separator == '(') { 449 separator = ','; 450 continue; 451 } 452 if (separator) 453 ptr += sprintf(ptr, "%c", separator); 454 if (operand->flags & OPERAND_GPR) 455 ptr += sprintf(ptr, "%%r%i", value); 456 else if (operand->flags & OPERAND_FPR) 457 ptr += sprintf(ptr, "%%f%i", value); 458 else if (operand->flags & OPERAND_AR) 459 ptr += sprintf(ptr, "%%a%i", value); 460 else if (operand->flags & OPERAND_CR) 461 ptr += sprintf(ptr, "%%c%i", value); 462 else if (operand->flags & OPERAND_VR) 463 ptr += sprintf(ptr, "%%v%i", value); 464 else if (operand->flags & OPERAND_PCREL) { 465 void *pcrel = (void *)((int)value + addr); 466 467 ptr += sprintf(ptr, "%px", pcrel); 468 } else if (operand->flags & OPERAND_SIGNED) 469 ptr += sprintf(ptr, "%i", value); 470 else 471 ptr += sprintf(ptr, "%u", value); 472 if (operand->flags & OPERAND_DISP) 473 separator = '('; 474 else if (operand->flags & OPERAND_BASE) { 475 ptr += sprintf(ptr, ")"); 476 separator = ','; 477 } else 478 separator = ','; 479 } 480 } else 481 ptr += sprintf(ptr, "unknown"); 482 return (int) (ptr - buffer); 483 } 484 485 static int copy_from_regs(struct pt_regs *regs, void *dst, void *src, int len) 486 { 487 if (user_mode(regs)) { 488 if (copy_from_user(dst, (char __user *)src, len)) 489 return -EFAULT; 490 } else { 491 if (copy_from_kernel_nofault(dst, src, len)) 492 return -EFAULT; 493 } 494 return 0; 495 } 496 497 void show_code(struct pt_regs *regs) 498 { 499 char *mode = user_mode(regs) ? "User" : "Krnl"; 500 unsigned char code[64]; 501 char buffer[128], *ptr; 502 unsigned long addr; 503 int start, end, opsize, hops, i; 504 505 /* Get a snapshot of the 64 bytes surrounding the fault address. */ 506 for (start = 32; start && regs->psw.addr >= 34 - start; start -= 2) { 507 addr = regs->psw.addr - 34 + start; 508 if (copy_from_regs(regs, code + start - 2, (void *)addr, 2)) 509 break; 510 } 511 for (end = 32; end < 64; end += 2) { 512 addr = regs->psw.addr + end - 32; 513 if (copy_from_regs(regs, code + end, (void *)addr, 2)) 514 break; 515 } 516 /* Code snapshot useable ? */ 517 if ((regs->psw.addr & 1) || start >= end) { 518 printk("%s Code: Bad PSW.\n", mode); 519 return; 520 } 521 /* Find a starting point for the disassembly. */ 522 while (start < 32) { 523 for (i = 0, hops = 0; start + i < 32 && hops < 3; hops++) { 524 if (!find_insn(code + start + i)) 525 break; 526 i += insn_length(code[start + i]); 527 } 528 if (start + i == 32) 529 /* Looks good, sequence ends at PSW. */ 530 break; 531 start += 2; 532 } 533 /* Decode the instructions. */ 534 ptr = buffer; 535 ptr += sprintf(ptr, "%s Code:", mode); 536 hops = 0; 537 while (start < end && hops < 8) { 538 opsize = insn_length(code[start]); 539 if (start + opsize == 32) 540 *ptr++ = '#'; 541 else if (start == 32) 542 *ptr++ = '>'; 543 else 544 *ptr++ = ' '; 545 addr = regs->psw.addr + start - 32; 546 ptr += sprintf(ptr, "%px: ", (void *)addr); 547 if (start + opsize >= end) 548 break; 549 for (i = 0; i < opsize; i++) 550 ptr += sprintf(ptr, "%02x", code[start + i]); 551 *ptr++ = '\t'; 552 if (i < 6) 553 *ptr++ = '\t'; 554 ptr += print_insn(ptr, code + start, addr); 555 start += opsize; 556 pr_cont("%s", buffer); 557 ptr = buffer; 558 ptr += sprintf(ptr, "\n "); 559 hops++; 560 } 561 pr_cont("\n"); 562 } 563 564 void print_fn_code(unsigned char *code, unsigned long len) 565 { 566 char buffer[128], *ptr; 567 int opsize, i; 568 569 while (len) { 570 ptr = buffer; 571 opsize = insn_length(*code); 572 if (opsize > len) 573 break; 574 ptr += sprintf(ptr, "%px: ", code); 575 for (i = 0; i < opsize; i++) 576 ptr += sprintf(ptr, "%02x", code[i]); 577 *ptr++ = '\t'; 578 if (i < 4) 579 *ptr++ = '\t'; 580 ptr += print_insn(ptr, code, (unsigned long) code); 581 *ptr++ = '\n'; 582 *ptr++ = 0; 583 printk("%s", buffer); 584 code += opsize; 585 len -= opsize; 586 } 587 } 588