arch/x86/mm/pf_in.c

   1 /*
   2  *  Fault Injection Test harness (FI)
   3  *  Copyright (C) Intel Crop.
   4  *
   5  *  This program is free software; you can redistribute it and/or
   6  *  modify it under the terms of the GNU General Public License
   7  *  as published by the Free Software Foundation; either version 2
   8  *  of the License, or (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
  18  *  USA.
  19  *
  20  */
  21
  22 /*  Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp
  23  *  Copyright by Intel Crop., 2002
  24  *  Louis Zhuang (louis.zhuang@intel.com)
  25  *
  26  *  Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007
  27  */
  28
  29 #include <linux/module.h>
  30 #include <linux/ptrace.h> /* struct pt_regs */
  31 #include "pf_in.h"
  32
  33 #ifdef __i386__
  34 /* IA32 Manual 3, 2-1 */
  35 static unsigned char prefix_codes[] = {
  36         0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64,
  37         0x65, 0x2E, 0x3E, 0x66, 0x67
  38 };
  39 /* IA32 Manual 3, 3-432*/
  40 static unsigned int reg_rop[] = {
  41         0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
  42 };
  43 static unsigned int reg_wop[] = { 0x88, 0x89 };
  44 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
  45 /* IA32 Manual 3, 3-432*/
  46 static unsigned int rw8[] = { 0x88, 0x8A, 0xC6 };
  47 static unsigned int rw32[] = {
  48         0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
  49 };
  50 static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F };
  51 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
  52 static unsigned int mw32[] = { 0x89, 0x8B, 0xC7 };
  53 static unsigned int mw64[] = {};
  54 #else /* not __i386__ */
  55 static unsigned char prefix_codes[] = {
  56         0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36,
  57         0xF0, 0xF3, 0xF2,
  58         /* REX Prefixes */
  59         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
  60         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
  61 };
  62 /* AMD64 Manual 3, Appendix A*/
  63 static unsigned int reg_rop[] = {
  64         0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
  65 };
  66 static unsigned int reg_wop[] = { 0x88, 0x89 };
  67 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
  68 static unsigned int rw8[] = { 0xC6, 0x88, 0x8A };
  69 static unsigned int rw32[] = {
  70         0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
  71 };
  72 /* 8 bit only */
  73 static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F };
  74 /* 16 bit only */
  75 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
  76 /* 16 or 32 bit */
  77 static unsigned int mw32[] = { 0xC7 };
  78 /* 16, 32 or 64 bit */
  79 static unsigned int mw64[] = { 0x89, 0x8B };
  80 #endif /* not __i386__ */
  81
  82 static int skip_prefix(unsigned char *addr, int *shorted, int *enlarged,
  83                                                                 int *rexr)
  84 {
  85         int i;
  86         unsigned char *p = addr;
  87         *shorted = 0;
  88         *enlarged = 0;
  89         *rexr = 0;
  90
  91 restart:
  92         for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) {
  93                 if (*p == prefix_codes[i]) {
  94                         if (*p == 0x66)
  95                                 *shorted = 1;
  96 #ifdef __amd64__
  97                         if ((*p & 0xf8) == 0x48)
  98                                 *enlarged = 1;
  99                         if ((*p & 0xf4) == 0x44)
 100                                 *rexr = 1;
 101 #endif
 102                         p++;
 103                         goto restart;
 104                 }
 105         }
 106
 107         return (p - addr);
 108 }
 109
 110 static int get_opcode(unsigned char *addr, unsigned int *opcode)
 111 {
 112         int len;
 113
 114         if (*addr == 0x0F) {
 115                 /* 0x0F is extension instruction */
 116                 *opcode = *(unsigned short *)addr;
 117                 len = 2;
 118         } else {
 119                 *opcode = *addr;
 120                 len = 1;
 121         }
 122
 123         return len;
 124 }
 125
 126 #define CHECK_OP_TYPE(opcode, array, type) \
 127         for (i = 0; i < ARRAY_SIZE(array); i++) { \
 128                 if (array[i] == opcode) { \
 129                         rv = type; \
 130                         goto exit; \
 131                 } \
 132         }
 133
 134 enum reason_type get_ins_type(unsigned long ins_addr)
 135 {
 136         unsigned int opcode;
 137         unsigned char *p;
 138         int shorted, enlarged, rexr;
 139         int i;
 140         enum reason_type rv = OTHERS;
 141
 142         p = (unsigned char *)ins_addr;
 143         p += skip_prefix(p, &shorted, &enlarged, &rexr);
 144         p += get_opcode(p, &opcode);
 145
 146         CHECK_OP_TYPE(opcode, reg_rop, REG_READ);
 147         CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE);
 148         CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE);
 149
 150 exit:
 151         return rv;
 152 }
 153 #undef CHECK_OP_TYPE
 154
 155 static unsigned int get_ins_reg_width(unsigned long ins_addr)
 156 {
 157         unsigned int opcode;
 158         unsigned char *p;
 159         int i, shorted, enlarged, rexr;
 160
 161         p = (unsigned char *)ins_addr;
 162         p += skip_prefix(p, &shorted, &enlarged, &rexr);
 163         p += get_opcode(p, &opcode);
 164
 165         for (i = 0; i < ARRAY_SIZE(rw8); i++)
 166                 if (rw8[i] == opcode)
 167                         return 1;
 168
 169         for (i = 0; i < ARRAY_SIZE(rw32); i++)
 170                 if (rw32[i] == opcode)
 171                         return (shorted ? 2 : (enlarged ? 8 : 4));
 172
 173         printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
 174         return 0;
 175 }
 176
 177 unsigned int get_ins_mem_width(unsigned long ins_addr)
 178 {
 179         unsigned int opcode;
 180         unsigned char *p;
 181         int i, shorted, enlarged, rexr;
 182
 183         p = (unsigned char *)ins_addr;
 184         p += skip_prefix(p, &shorted, &enlarged, &rexr);
 185         p += get_opcode(p, &opcode);
 186
 187         for (i = 0; i < ARRAY_SIZE(mw8); i++)
 188                 if (mw8[i] == opcode)
 189                         return 1;
 190
 191         for (i = 0; i < ARRAY_SIZE(mw16); i++)
 192                 if (mw16[i] == opcode)
 193                         return 2;
 194
 195         for (i = 0; i < ARRAY_SIZE(mw32); i++)
 196                 if (mw32[i] == opcode)
 197                         return shorted ? 2 : 4;
 198
 199         for (i = 0; i < ARRAY_SIZE(mw64); i++)
 200                 if (mw64[i] == opcode)
 201                         return shorted ? 2 : (enlarged ? 8 : 4);
 202
 203         printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
 204         return 0;
 205 }
 206
 207 /*
 208  * Define register ident in mod/rm byte.
 209  * Note: these are NOT the same as in ptrace-abi.h.
 210  */
 211 enum {
 212         arg_AL = 0,
 213         arg_CL = 1,
 214         arg_DL = 2,
 215         arg_BL = 3,
 216         arg_AH = 4,
 217         arg_CH = 5,
 218         arg_DH = 6,
 219         arg_BH = 7,
 220
 221         arg_AX = 0,
 222         arg_CX = 1,
 223         arg_DX = 2,
 224         arg_BX = 3,
 225         arg_SP = 4,
 226         arg_BP = 5,
 227         arg_SI = 6,
 228         arg_DI = 7,
 229 #ifdef __amd64__
 230         arg_R8  = 8,
 231         arg_R9  = 9,
 232         arg_R10 = 10,
 233         arg_R11 = 11,
 234         arg_R12 = 12,
 235         arg_R13 = 13,
 236         arg_R14 = 14,
 237         arg_R15 = 15
 238 #endif
 239 };
 240
 241 static unsigned char *get_reg_w8(int no, struct pt_regs *regs)
 242 {
 243         unsigned char *rv = NULL;
 244
 245         switch (no) {
 246         case arg_AL:
 247                 rv = (unsigned char *)&regs->ax;
 248                 break;
 249         case arg_BL:
 250                 rv = (unsigned char *)&regs->bx;
 251                 break;
 252         case arg_CL:
 253                 rv = (unsigned char *)&regs->cx;
 254                 break;
 255         case arg_DL:
 256                 rv = (unsigned char *)&regs->dx;
 257                 break;
 258         case arg_AH:
 259                 rv = 1 + (unsigned char *)&regs->ax;
 260                 break;
 261         case arg_BH:
 262                 rv = 1 + (unsigned char *)&regs->bx;
 263                 break;
 264         case arg_CH:
 265                 rv = 1 + (unsigned char *)&regs->cx;
 266                 break;
 267         case arg_DH:
 268                 rv = 1 + (unsigned char *)&regs->dx;
 269                 break;
 270 #ifdef __amd64__
 271         case arg_R8:
 272                 rv = (unsigned char *)&regs->r8;
 273                 break;
 274         case arg_R9:
 275                 rv = (unsigned char *)&regs->r9;
 276                 break;
 277         case arg_R10:
 278                 rv = (unsigned char *)&regs->r10;
 279                 break;
 280         case arg_R11:
 281                 rv = (unsigned char *)&regs->r11;
 282                 break;
 283         case arg_R12:
 284                 rv = (unsigned char *)&regs->r12;
 285                 break;
 286         case arg_R13:
 287                 rv = (unsigned char *)&regs->r13;
 288                 break;
 289         case arg_R14:
 290                 rv = (unsigned char *)&regs->r14;
 291                 break;
 292         case arg_R15:
 293                 rv = (unsigned char *)&regs->r15;
 294                 break;
 295 #endif
 296         default:
 297                 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
 298                 break;
 299         }
 300         return rv;
 301 }
 302
 303 static unsigned long *get_reg_w32(int no, struct pt_regs *regs)
 304 {
 305         unsigned long *rv = NULL;
 306
 307         switch (no) {
 308         case arg_AX:
 309                 rv = &regs->ax;
 310                 break;
 311         case arg_BX:
 312                 rv = &regs->bx;
 313                 break;
 314         case arg_CX:
 315                 rv = &regs->cx;
 316                 break;
 317         case arg_DX:
 318                 rv = &regs->dx;
 319                 break;
 320         case arg_SP:
 321                 rv = &regs->sp;
 322                 break;
 323         case arg_BP:
 324                 rv = &regs->bp;
 325                 break;
 326         case arg_SI:
 327                 rv = &regs->si;
 328                 break;
 329         case arg_DI:
 330                 rv = &regs->di;
 331                 break;
 332 #ifdef __amd64__
 333         case arg_R8:
 334                 rv = &regs->r8;
 335                 break;
 336         case arg_R9:
 337                 rv = &regs->r9;
 338                 break;
 339         case arg_R10:
 340                 rv = &regs->r10;
 341                 break;
 342         case arg_R11:
 343                 rv = &regs->r11;
 344                 break;
 345         case arg_R12:
 346                 rv = &regs->r12;
 347                 break;
 348         case arg_R13:
 349                 rv = &regs->r13;
 350                 break;
 351         case arg_R14:
 352                 rv = &regs->r14;
 353                 break;
 354         case arg_R15:
 355                 rv = &regs->r15;
 356                 break;
 357 #endif
 358         default:
 359                 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
 360         }
 361
 362         return rv;
 363 }
 364
 365 unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs)
 366 {
 367         unsigned int opcode;
 368         unsigned char mod_rm;
 369         int reg;
 370         unsigned char *p;
 371         int i, shorted, enlarged, rexr;
 372         unsigned long rv;
 373
 374         p = (unsigned char *)ins_addr;
 375         p += skip_prefix(p, &shorted, &enlarged, &rexr);
 376         p += get_opcode(p, &opcode);
 377         for (i = 0; i < ARRAY_SIZE(reg_rop); i++)
 378                 if (reg_rop[i] == opcode) {
 379                         rv = REG_READ;
 380                         goto do_work;
 381                 }
 382
 383         for (i = 0; i < ARRAY_SIZE(reg_wop); i++)
 384                 if (reg_wop[i] == opcode) {
 385                         rv = REG_WRITE;
 386                         goto do_work;
 387                 }
 388
 389         printk(KERN_ERR "mmiotrace: Not a register instruction, opcode "
 390                                                         "0x%02x\n", opcode);
 391         goto err;
 392
 393 do_work:
 394         mod_rm = *p;
 395         reg = ((mod_rm >> 3) & 0x7) | (rexr << 3);
 396         switch (get_ins_reg_width(ins_addr)) {
 397         case 1:
 398                 return *get_reg_w8(reg, regs);
 399
 400         case 2:
 401                 return *(unsigned short *)get_reg_w32(reg, regs);
 402
 403         case 4:
 404                 return *(unsigned int *)get_reg_w32(reg, regs);
 405
 406 #ifdef __amd64__
 407         case 8:
 408                 return *(unsigned long *)get_reg_w32(reg, regs);
 409 #endif
 410
 411         default:
 412                 printk(KERN_ERR "mmiotrace: Error width# %d\n", reg);
 413         }
 414
 415 err:
 416         return 0;
 417 }
 418
 419 unsigned long get_ins_imm_val(unsigned long ins_addr)
 420 {
 421         unsigned int opcode;
 422         unsigned char mod_rm;
 423         unsigned char mod;
 424         unsigned char *p;
 425         int i, shorted, enlarged, rexr;
 426         unsigned long rv;
 427
 428         p = (unsigned char *)ins_addr;
 429         p += skip_prefix(p, &shorted, &enlarged, &rexr);
 430         p += get_opcode(p, &opcode);
 431         for (i = 0; i < ARRAY_SIZE(imm_wop); i++)
 432                 if (imm_wop[i] == opcode) {
 433                         rv = IMM_WRITE;
 434                         goto do_work;
 435                 }
 436
 437         printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode "
 438                                                         "0x%02x\n", opcode);
 439         goto err;
 440
 441 do_work:
 442         mod_rm = *p;
 443         mod = mod_rm >> 6;
 444         p++;
 445         switch (mod) {
 446         case 0:
 447                 /* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2)  */
 448                 /* AMD64: XXX Check for address size prefix? */
 449                 if ((mod_rm & 0x7) == 0x5)
 450                         p += 4;
 451                 break;
 452
 453         case 1:
 454                 p += 1;
 455                 break;
 456
 457         case 2:
 458                 p += 4;
 459                 break;
 460
 461         case 3:
 462         default:
 463                 printk(KERN_ERR "mmiotrace: not a memory access instruction "
 464                                                 "at 0x%lx, rm_mod=0x%02x\n",
 465                                                 ins_addr, mod_rm);
 466         }
 467
 468         switch (get_ins_reg_width(ins_addr)) {
 469         case 1:
 470                 return *(unsigned char *)p;
 471
 472         case 2:
 473                 return *(unsigned short *)p;
 474
 475         case 4:
 476                 return *(unsigned int *)p;
 477
 478 #ifdef __amd64__
 479         case 8:
 480                 return *(unsigned long *)p;
 481 #endif
 482
 483         default:
 484                 printk(KERN_ERR "mmiotrace: Error: width.\n");
 485         }
 486
 487 err:
 488         return 0;
 489 }