arch/powerpc/kernel/ptrace.c

   1 /*
   2  *  PowerPC version
   3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   4  *
   5  *  Derived from "arch/m68k/kernel/ptrace.c"
   6  *  Copyright (C) 1994 by Hamish Macdonald
   7  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
   8  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
   9  *
  10  * Modified by Cort Dougan (cort@hq.fsmlabs.com)
  11  * and Paul Mackerras (paulus@samba.org).
  12  *
  13  * This file is subject to the terms and conditions of the GNU General
  14  * Public License.  See the file README.legal in the main directory of
  15  * this archive for more details.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/mm.h>
  21 #include <linux/smp.h>
  22 #include <linux/errno.h>
  23 #include <linux/ptrace.h>
  24 #include <linux/regset.h>
  25 #include <linux/elf.h>
  26 #include <linux/user.h>
  27 #include <linux/security.h>
  28 #include <linux/signal.h>
  29 #include <linux/seccomp.h>
  30 #include <linux/audit.h>
  31 #ifdef CONFIG_PPC32
  32 #include <linux/module.h>
  33 #endif
  34
  35 #include <asm/uaccess.h>
  36 #include <asm/page.h>
  37 #include <asm/pgtable.h>
  38 #include <asm/system.h>
  39
  40 /*
  41  * does not yet catch signals sent when the child dies.
  42  * in exit.c or in signal.c.
  43  */
  44
  45 /*
  46  * Set of msr bits that gdb can change on behalf of a process.
  47  */
  48 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
  49 #define MSR_DEBUGCHANGE 0
  50 #else
  51 #define MSR_DEBUGCHANGE (MSR_SE | MSR_BE)
  52 #endif
  53
  54 /*
  55  * Max register writeable via put_reg
  56  */
  57 #ifdef CONFIG_PPC32
  58 #define PT_MAX_PUT_REG  PT_MQ
  59 #else
  60 #define PT_MAX_PUT_REG  PT_CCR
  61 #endif
  62
  63 static unsigned long get_user_msr(struct task_struct *task)
  64 {
  65         return task->thread.regs->msr | task->thread.fpexc_mode;
  66 }
  67
  68 static int set_user_msr(struct task_struct *task, unsigned long msr)
  69 {
  70         task->thread.regs->msr &= ~MSR_DEBUGCHANGE;
  71         task->thread.regs->msr |= msr & MSR_DEBUGCHANGE;
  72         return 0;
  73 }
  74
  75 /*
  76  * We prevent mucking around with the reserved area of trap
  77  * which are used internally by the kernel.
  78  */
  79 static int set_user_trap(struct task_struct *task, unsigned long trap)
  80 {
  81         task->thread.regs->trap = trap & 0xfff0;
  82         return 0;
  83 }
  84
  85 /*
  86  * Get contents of register REGNO in task TASK.
  87  */
  88 unsigned long ptrace_get_reg(struct task_struct *task, int regno)
  89 {
  90         if (task->thread.regs == NULL)
  91                 return -EIO;
  92
  93         if (regno == PT_MSR)
  94                 return get_user_msr(task);
  95
  96         if (regno < (sizeof(struct pt_regs) / sizeof(unsigned long)))
  97                 return ((unsigned long *)task->thread.regs)[regno];
  98
  99         return -EIO;
 100 }
 101
 102 /*
 103  * Write contents of register REGNO in task TASK.
 104  */
 105 int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data)
 106 {
 107         if (task->thread.regs == NULL)
 108                 return -EIO;
 109
 110         if (regno == PT_MSR)
 111                 return set_user_msr(task, data);
 112         if (regno == PT_TRAP)
 113                 return set_user_trap(task, data);
 114
 115         if (regno <= PT_MAX_PUT_REG) {
 116                 ((unsigned long *)task->thread.regs)[regno] = data;
 117                 return 0;
 118         }
 119         return -EIO;
 120 }
 121
 122 static int gpr_get(struct task_struct *target, const struct user_regset *regset,
 123                    unsigned int pos, unsigned int count,
 124                    void *kbuf, void __user *ubuf)
 125 {
 126         int ret;
 127
 128         if (target->thread.regs == NULL)
 129                 return -EIO;
 130
 131         CHECK_FULL_REGS(target->thread.regs);
 132
 133         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 134                                   target->thread.regs,
 135                                   0, offsetof(struct pt_regs, msr));
 136         if (!ret) {
 137                 unsigned long msr = get_user_msr(target);
 138                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &msr,
 139                                           offsetof(struct pt_regs, msr),
 140                                           offsetof(struct pt_regs, msr) +
 141                                           sizeof(msr));
 142         }
 143
 144         BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
 145                      offsetof(struct pt_regs, msr) + sizeof(long));
 146
 147         if (!ret)
 148                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 149                                           &target->thread.regs->orig_gpr3,
 150                                           offsetof(struct pt_regs, orig_gpr3),
 151                                           sizeof(struct pt_regs));
 152         if (!ret)
 153                 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 154                                                sizeof(struct pt_regs), -1);
 155
 156         return ret;
 157 }
 158
 159 static int gpr_set(struct task_struct *target, const struct user_regset *regset,
 160                    unsigned int pos, unsigned int count,
 161                    const void *kbuf, const void __user *ubuf)
 162 {
 163         unsigned long reg;
 164         int ret;
 165
 166         if (target->thread.regs == NULL)
 167                 return -EIO;
 168
 169         CHECK_FULL_REGS(target->thread.regs);
 170
 171         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 172                                  target->thread.regs,
 173                                  0, PT_MSR * sizeof(reg));
 174
 175         if (!ret && count > 0) {
 176                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &reg,
 177                                          PT_MSR * sizeof(reg),
 178                                          (PT_MSR + 1) * sizeof(reg));
 179                 if (!ret)
 180                         ret = set_user_msr(target, reg);
 181         }
 182
 183         BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
 184                      offsetof(struct pt_regs, msr) + sizeof(long));
 185
 186         if (!ret)
 187                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 188                                          &target->thread.regs->orig_gpr3,
 189                                          PT_ORIG_R3 * sizeof(reg),
 190                                          (PT_MAX_PUT_REG + 1) * sizeof(reg));
 191
 192         if (PT_MAX_PUT_REG + 1 < PT_TRAP && !ret)
 193                 ret = user_regset_copyin_ignore(
 194                         &pos, &count, &kbuf, &ubuf,
 195                         (PT_MAX_PUT_REG + 1) * sizeof(reg),
 196                         PT_TRAP * sizeof(reg));
 197
 198         if (!ret && count > 0) {
 199                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &reg,
 200                                          PT_TRAP * sizeof(reg),
 201                                          (PT_TRAP + 1) * sizeof(reg));
 202                 if (!ret)
 203                         ret = set_user_trap(target, reg);
 204         }
 205
 206         if (!ret)
 207                 ret = user_regset_copyin_ignore(
 208                         &pos, &count, &kbuf, &ubuf,
 209                         (PT_TRAP + 1) * sizeof(reg), -1);
 210
 211         return ret;
 212 }
 213
 214 static int fpr_get(struct task_struct *target, const struct user_regset *regset,
 215                    unsigned int pos, unsigned int count,
 216                    void *kbuf, void __user *ubuf)
 217 {
 218         flush_fp_to_thread(target);
 219
 220         BUILD_BUG_ON(offsetof(struct thread_struct, fpscr) !=
 221                      offsetof(struct thread_struct, fpr[32]));
 222
 223         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 224                                    &target->thread.fpr, 0, -1);
 225 }
 226
 227 static int fpr_set(struct task_struct *target, const struct user_regset *regset,
 228                    unsigned int pos, unsigned int count,
 229                    const void *kbuf, const void __user *ubuf)
 230 {
 231         flush_fp_to_thread(target);
 232
 233         BUILD_BUG_ON(offsetof(struct thread_struct, fpscr) !=
 234                      offsetof(struct thread_struct, fpr[32]));
 235
 236         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 237                                   &target->thread.fpr, 0, -1);
 238 }
 239
 240
 241 #ifdef CONFIG_ALTIVEC
 242 /*
 243  * Get/set all the altivec registers vr0..vr31, vscr, vrsave, in one go.
 244  * The transfer totals 34 quadword.  Quadwords 0-31 contain the
 245  * corresponding vector registers.  Quadword 32 contains the vscr as the
 246  * last word (offset 12) within that quadword.  Quadword 33 contains the
 247  * vrsave as the first word (offset 0) within the quadword.
 248  *
 249  * This definition of the VMX state is compatible with the current PPC32
 250  * ptrace interface.  This allows signal handling and ptrace to use the
 251  * same structures.  This also simplifies the implementation of a bi-arch
 252  * (combined (32- and 64-bit) gdb.
 253  */
 254
 255 static int vr_active(struct task_struct *target,
 256                      const struct user_regset *regset)
 257 {
 258         flush_altivec_to_thread(target);
 259         return target->thread.used_vr ? regset->n : 0;
 260 }
 261
 262 static int vr_get(struct task_struct *target, const struct user_regset *regset,
 263                   unsigned int pos, unsigned int count,
 264                   void *kbuf, void __user *ubuf)
 265 {
 266         int ret;
 267
 268         flush_altivec_to_thread(target);
 269
 270         BUILD_BUG_ON(offsetof(struct thread_struct, vscr) !=
 271                      offsetof(struct thread_struct, vr[32]));
 272
 273         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 274                                   &target->thread.vr, 0,
 275                                   33 * sizeof(vector128));
 276         if (!ret) {
 277                 /*
 278                  * Copy out only the low-order word of vrsave.
 279                  */
 280                 union {
 281                         elf_vrreg_t reg;
 282                         u32 word;
 283                 } vrsave;
 284                 memset(&vrsave, 0, sizeof(vrsave));
 285                 vrsave.word = target->thread.vrsave;
 286                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
 287                                           33 * sizeof(vector128), -1);
 288         }
 289
 290         return ret;
 291 }
 292
 293 static int vr_set(struct task_struct *target, const struct user_regset *regset,
 294                   unsigned int pos, unsigned int count,
 295                   const void *kbuf, const void __user *ubuf)
 296 {
 297         int ret;
 298
 299         flush_altivec_to_thread(target);
 300
 301         BUILD_BUG_ON(offsetof(struct thread_struct, vscr) !=
 302                      offsetof(struct thread_struct, vr[32]));
 303
 304         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 305                                  &target->thread.vr, 0, 33 * sizeof(vector128));
 306         if (!ret && count > 0) {
 307                 /*
 308                  * We use only the first word of vrsave.
 309                  */
 310                 union {
 311                         elf_vrreg_t reg;
 312                         u32 word;
 313                 } vrsave;
 314                 memset(&vrsave, 0, sizeof(vrsave));
 315                 vrsave.word = target->thread.vrsave;
 316                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &vrsave,
 317                                          33 * sizeof(vector128), -1);
 318                 if (!ret)
 319                         target->thread.vrsave = vrsave.word;
 320         }
 321
 322         return ret;
 323 }
 324 #endif /* CONFIG_ALTIVEC */
 325
 326 #ifdef CONFIG_SPE
 327
 328 /*
 329  * For get_evrregs/set_evrregs functions 'data' has the following layout:
 330  *
 331  * struct {
 332  *   u32 evr[32];
 333  *   u64 acc;
 334  *   u32 spefscr;
 335  * }
 336  */
 337
 338 static int evr_active(struct task_struct *target,
 339                       const struct user_regset *regset)
 340 {
 341         flush_spe_to_thread(target);
 342         return target->thread.used_spe ? regset->n : 0;
 343 }
 344
 345 static int evr_get(struct task_struct *target, const struct user_regset *regset,
 346                    unsigned int pos, unsigned int count,
 347                    void *kbuf, void __user *ubuf)
 348 {
 349         int ret;
 350
 351         flush_spe_to_thread(target);
 352
 353         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 354                                   &target->thread.evr,
 355                                   0, sizeof(target->thread.evr));
 356
 357         BUILD_BUG_ON(offsetof(struct thread_struct, acc) + sizeof(u64) !=
 358                      offsetof(struct thread_struct, spefscr));
 359
 360         if (!ret)
 361                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 362                                           &target->thread.acc,
 363                                           sizeof(target->thread.evr), -1);
 364
 365         return ret;
 366 }
 367
 368 static int evr_set(struct task_struct *target, const struct user_regset *regset,
 369                    unsigned int pos, unsigned int count,
 370                    const void *kbuf, const void __user *ubuf)
 371 {
 372         int ret;
 373
 374         flush_spe_to_thread(target);
 375
 376         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 377                                  &target->thread.evr,
 378                                  0, sizeof(target->thread.evr));
 379
 380         BUILD_BUG_ON(offsetof(struct thread_struct, acc) + sizeof(u64) !=
 381                      offsetof(struct thread_struct, spefscr));
 382
 383         if (!ret)
 384                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 385                                          &target->thread.acc,
 386                                          sizeof(target->thread.evr), -1);
 387
 388         return ret;
 389 }
 390 #endif /* CONFIG_SPE */
 391
 392
 393 /*
 394  * These are our native regset flavors.
 395  */
 396 enum powerpc_regset {
 397         REGSET_GPR,
 398         REGSET_FPR,
 399 #ifdef CONFIG_ALTIVEC
 400         REGSET_VMX,
 401 #endif
 402 #ifdef CONFIG_SPE
 403         REGSET_SPE,
 404 #endif
 405 };
 406
 407 static const struct user_regset native_regsets[] = {
 408         [REGSET_GPR] = {
 409                 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 410                 .size = sizeof(long), .align = sizeof(long),
 411                 .get = gpr_get, .set = gpr_set
 412         },
 413         [REGSET_FPR] = {
 414                 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 415                 .size = sizeof(double), .align = sizeof(double),
 416                 .get = fpr_get, .set = fpr_set
 417         },
 418 #ifdef CONFIG_ALTIVEC
 419         [REGSET_VMX] = {
 420                 .core_note_type = NT_PPC_VMX, .n = 34,
 421                 .size = sizeof(vector128), .align = sizeof(vector128),
 422                 .active = vr_active, .get = vr_get, .set = vr_set
 423         },
 424 #endif
 425 #ifdef CONFIG_SPE
 426         [REGSET_SPE] = {
 427                 .n = 35,
 428                 .size = sizeof(u32), .align = sizeof(u32),
 429                 .active = evr_active, .get = evr_get, .set = evr_set
 430         },
 431 #endif
 432 };
 433
 434 static const struct user_regset_view user_ppc_native_view = {
 435         .name = UTS_MACHINE, .e_machine = ELF_ARCH, .ei_osabi = ELF_OSABI,
 436         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
 437 };
 438
 439 #ifdef CONFIG_PPC64
 440 #include <linux/compat.h>
 441
 442 static int gpr32_get(struct task_struct *target,
 443                      const struct user_regset *regset,
 444                      unsigned int pos, unsigned int count,
 445                      void *kbuf, void __user *ubuf)
 446 {
 447         const unsigned long *regs = &target->thread.regs->gpr[0];
 448         compat_ulong_t *k = kbuf;
 449         compat_ulong_t __user *u = ubuf;
 450         compat_ulong_t reg;
 451
 452         if (target->thread.regs == NULL)
 453                 return -EIO;
 454
 455         CHECK_FULL_REGS(target->thread.regs);
 456
 457         pos /= sizeof(reg);
 458         count /= sizeof(reg);
 459
 460         if (kbuf)
 461                 for (; count > 0 && pos < PT_MSR; --count)
 462                         *k++ = regs[pos++];
 463         else
 464                 for (; count > 0 && pos < PT_MSR; --count)
 465                         if (__put_user((compat_ulong_t) regs[pos++], u++))
 466                                 return -EFAULT;
 467
 468         if (count > 0 && pos == PT_MSR) {
 469                 reg = get_user_msr(target);
 470                 if (kbuf)
 471                         *k++ = reg;
 472                 else if (__put_user(reg, u++))
 473                         return -EFAULT;
 474                 ++pos;
 475                 --count;
 476         }
 477
 478         if (kbuf)
 479                 for (; count > 0 && pos < PT_REGS_COUNT; --count)
 480                         *k++ = regs[pos++];
 481         else
 482                 for (; count > 0 && pos < PT_REGS_COUNT; --count)
 483                         if (__put_user((compat_ulong_t) regs[pos++], u++))
 484                                 return -EFAULT;
 485
 486         kbuf = k;
 487         ubuf = u;
 488         pos *= sizeof(reg);
 489         count *= sizeof(reg);
 490         return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 491                                         PT_REGS_COUNT * sizeof(reg), -1);
 492 }
 493
 494 static int gpr32_set(struct task_struct *target,
 495                      const struct user_regset *regset,
 496                      unsigned int pos, unsigned int count,
 497                      const void *kbuf, const void __user *ubuf)
 498 {
 499         unsigned long *regs = &target->thread.regs->gpr[0];
 500         const compat_ulong_t *k = kbuf;
 501         const compat_ulong_t __user *u = ubuf;
 502         compat_ulong_t reg;
 503
 504         if (target->thread.regs == NULL)
 505                 return -EIO;
 506
 507         CHECK_FULL_REGS(target->thread.regs);
 508
 509         pos /= sizeof(reg);
 510         count /= sizeof(reg);
 511
 512         if (kbuf)
 513                 for (; count > 0 && pos < PT_MSR; --count)
 514                         regs[pos++] = *k++;
 515         else
 516                 for (; count > 0 && pos < PT_MSR; --count) {
 517                         if (__get_user(reg, u++))
 518                                 return -EFAULT;
 519                         regs[pos++] = reg;
 520                 }
 521
 522
 523         if (count > 0 && pos == PT_MSR) {
 524                 if (kbuf)
 525                         reg = *k++;
 526                 else if (__get_user(reg, u++))
 527                         return -EFAULT;
 528                 set_user_msr(target, reg);
 529                 ++pos;
 530                 --count;
 531         }
 532
 533         if (kbuf) {
 534                 for (; count > 0 && pos <= PT_MAX_PUT_REG; --count)
 535                         regs[pos++] = *k++;
 536                 for (; count > 0 && pos < PT_TRAP; --count, ++pos)
 537                         ++k;
 538         } else {
 539                 for (; count > 0 && pos <= PT_MAX_PUT_REG; --count) {
 540                         if (__get_user(reg, u++))
 541                                 return -EFAULT;
 542                         regs[pos++] = reg;
 543                 }
 544                 for (; count > 0 && pos < PT_TRAP; --count, ++pos)
 545                         if (__get_user(reg, u++))
 546                                 return -EFAULT;
 547         }
 548
 549         if (count > 0 && pos == PT_TRAP) {
 550                 if (kbuf)
 551                         reg = *k++;
 552                 else if (__get_user(reg, u++))
 553                         return -EFAULT;
 554                 set_user_trap(target, reg);
 555                 ++pos;
 556                 --count;
 557         }
 558
 559         kbuf = k;
 560         ubuf = u;
 561         pos *= sizeof(reg);
 562         count *= sizeof(reg);
 563         return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 564                                          (PT_TRAP + 1) * sizeof(reg), -1);
 565 }
 566
 567 /*
 568  * These are the regset flavors matching the CONFIG_PPC32 native set.
 569  */
 570 static const struct user_regset compat_regsets[] = {
 571         [REGSET_GPR] = {
 572                 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 573                 .size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
 574                 .get = gpr32_get, .set = gpr32_set
 575         },
 576         [REGSET_FPR] = {
 577                 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 578                 .size = sizeof(double), .align = sizeof(double),
 579                 .get = fpr_get, .set = fpr_set
 580         },
 581 #ifdef CONFIG_ALTIVEC
 582         [REGSET_VMX] = {
 583                 .core_note_type = NT_PPC_VMX, .n = 34,
 584                 .size = sizeof(vector128), .align = sizeof(vector128),
 585                 .active = vr_active, .get = vr_get, .set = vr_set
 586         },
 587 #endif
 588 #ifdef CONFIG_SPE
 589         [REGSET_SPE] = {
 590                 .core_note_type = NT_PPC_SPE, .n = 35,
 591                 .size = sizeof(u32), .align = sizeof(u32),
 592                 .active = evr_active, .get = evr_get, .set = evr_set
 593         },
 594 #endif
 595 };
 596
 597 static const struct user_regset_view user_ppc_compat_view = {
 598         .name = "ppc", .e_machine = EM_PPC, .ei_osabi = ELF_OSABI,
 599         .regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
 600 };
 601 #endif  /* CONFIG_PPC64 */
 602
 603 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 604 {
 605 #ifdef CONFIG_PPC64
 606         if (test_tsk_thread_flag(task, TIF_32BIT))
 607                 return &user_ppc_compat_view;
 608 #endif
 609         return &user_ppc_native_view;
 610 }
 611
 612
 613 void user_enable_single_step(struct task_struct *task)
 614 {
 615         struct pt_regs *regs = task->thread.regs;
 616
 617         if (regs != NULL) {
 618 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
 619                 task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC;
 620                 regs->msr |= MSR_DE;
 621 #else
 622                 regs->msr |= MSR_SE;
 623 #endif
 624         }
 625         set_tsk_thread_flag(task, TIF_SINGLESTEP);
 626 }
 627
 628 void user_disable_single_step(struct task_struct *task)
 629 {
 630         struct pt_regs *regs = task->thread.regs;
 631
 632         if (regs != NULL) {
 633 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
 634                 task->thread.dbcr0 = 0;
 635                 regs->msr &= ~MSR_DE;
 636 #else
 637                 regs->msr &= ~MSR_SE;
 638 #endif
 639         }
 640         clear_tsk_thread_flag(task, TIF_SINGLESTEP);
 641 }
 642
 643 static int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
 644                                unsigned long data)
 645 {
 646         /* We only support one DABR and no IABRS at the moment */
 647         if (addr > 0)
 648                 return -EINVAL;
 649
 650         /* The bottom 3 bits are flags */
 651         if ((data & ~0x7UL) >= TASK_SIZE)
 652                 return -EIO;
 653
 654         /* Ensure translation is on */
 655         if (data && !(data & DABR_TRANSLATION))
 656                 return -EIO;
 657
 658         task->thread.dabr = data;
 659         return 0;
 660 }
 661
 662 /*
 663  * Called by kernel/ptrace.c when detaching..
 664  *
 665  * Make sure single step bits etc are not set.
 666  */
 667 void ptrace_disable(struct task_struct *child)
 668 {
 669         /* make sure the single step bit is not set. */
 670         user_disable_single_step(child);
 671 }
 672
 673 /*
 674  * Here are the old "legacy" powerpc specific getregs/setregs ptrace calls,
 675  * we mark them as obsolete now, they will be removed in a future version
 676  */
 677 static long arch_ptrace_old(struct task_struct *child, long request, long addr,
 678                             long data)
 679 {
 680         switch (request) {
 681         case PPC_PTRACE_GETREGS:        /* Get GPRs 0 - 31. */
 682                 return copy_regset_to_user(child, &user_ppc_native_view,
 683                                            REGSET_GPR, 0, 32 * sizeof(long),
 684                                            (void __user *) data);
 685
 686         case PPC_PTRACE_SETREGS:        /* Set GPRs 0 - 31. */
 687                 return copy_regset_from_user(child, &user_ppc_native_view,
 688                                              REGSET_GPR, 0, 32 * sizeof(long),
 689                                              (const void __user *) data);
 690
 691         case PPC_PTRACE_GETFPREGS:      /* Get FPRs 0 - 31. */
 692                 return copy_regset_to_user(child, &user_ppc_native_view,
 693                                            REGSET_FPR, 0, 32 * sizeof(double),
 694                                            (void __user *) data);
 695
 696         case PPC_PTRACE_SETFPREGS:      /* Set FPRs 0 - 31. */
 697                 return copy_regset_from_user(child, &user_ppc_native_view,
 698                                              REGSET_FPR, 0, 32 * sizeof(double),
 699                                              (const void __user *) data);
 700         }
 701
 702         return -EPERM;
 703 }
 704
 705 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 706 {
 707         int ret = -EPERM;
 708
 709         switch (request) {
 710         /* read the word at location addr in the USER area. */
 711         case PTRACE_PEEKUSR: {
 712                 unsigned long index, tmp;
 713
 714                 ret = -EIO;
 715                 /* convert to index and check */
 716 #ifdef CONFIG_PPC32
 717                 index = (unsigned long) addr >> 2;
 718                 if ((addr & 3) || (index > PT_FPSCR)
 719                     || (child->thread.regs == NULL))
 720 #else
 721                 index = (unsigned long) addr >> 3;
 722                 if ((addr & 7) || (index > PT_FPSCR))
 723 #endif
 724                         break;
 725
 726                 CHECK_FULL_REGS(child->thread.regs);
 727                 if (index < PT_FPR0) {
 728                         tmp = ptrace_get_reg(child, (int) index);
 729                 } else {
 730                         flush_fp_to_thread(child);
 731                         tmp = ((unsigned long *)child->thread.fpr)[index - PT_FPR0];
 732                 }
 733                 ret = put_user(tmp,(unsigned long __user *) data);
 734                 break;
 735         }
 736
 737         /* write the word at location addr in the USER area */
 738         case PTRACE_POKEUSR: {
 739                 unsigned long index;
 740
 741                 ret = -EIO;
 742                 /* convert to index and check */
 743 #ifdef CONFIG_PPC32
 744                 index = (unsigned long) addr >> 2;
 745                 if ((addr & 3) || (index > PT_FPSCR)
 746                     || (child->thread.regs == NULL))
 747 #else
 748                 index = (unsigned long) addr >> 3;
 749                 if ((addr & 7) || (index > PT_FPSCR))
 750 #endif
 751                         break;
 752
 753                 CHECK_FULL_REGS(child->thread.regs);
 754                 if (index < PT_FPR0) {
 755                         ret = ptrace_put_reg(child, index, data);
 756                 } else {
 757                         flush_fp_to_thread(child);
 758                         ((unsigned long *)child->thread.fpr)[index - PT_FPR0] = data;
 759                         ret = 0;
 760                 }
 761                 break;
 762         }
 763
 764         case PTRACE_GET_DEBUGREG: {
 765                 ret = -EINVAL;
 766                 /* We only support one DABR and no IABRS at the moment */
 767                 if (addr > 0)
 768                         break;
 769                 ret = put_user(child->thread.dabr,
 770                                (unsigned long __user *)data);
 771                 break;
 772         }
 773
 774         case PTRACE_SET_DEBUGREG:
 775                 ret = ptrace_set_debugreg(child, addr, data);
 776                 break;
 777
 778 #ifdef CONFIG_PPC64
 779         case PTRACE_GETREGS64:
 780 #endif
 781         case PTRACE_GETREGS:    /* Get all pt_regs from the child. */
 782                 return copy_regset_to_user(child, &user_ppc_native_view,
 783                                            REGSET_GPR,
 784                                            0, sizeof(struct pt_regs),
 785                                            (void __user *) data);
 786
 787 #ifdef CONFIG_PPC64
 788         case PTRACE_SETREGS64:
 789 #endif
 790         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 791                 return copy_regset_from_user(child, &user_ppc_native_view,
 792                                              REGSET_GPR,
 793                                              0, sizeof(struct pt_regs),
 794                                              (const void __user *) data);
 795
 796         case PTRACE_GETFPREGS: /* Get the child FPU state (FPR0...31 + FPSCR) */
 797                 return copy_regset_to_user(child, &user_ppc_native_view,
 798                                            REGSET_FPR,
 799                                            0, sizeof(elf_fpregset_t),
 800                                            (void __user *) data);
 801
 802         case PTRACE_SETFPREGS: /* Set the child FPU state (FPR0...31 + FPSCR) */
 803                 return copy_regset_from_user(child, &user_ppc_native_view,
 804                                              REGSET_FPR,
 805                                              0, sizeof(elf_fpregset_t),
 806                                              (const void __user *) data);
 807
 808 #ifdef CONFIG_ALTIVEC
 809         case PTRACE_GETVRREGS:
 810                 return copy_regset_to_user(child, &user_ppc_native_view,
 811                                            REGSET_VMX,
 812                                            0, (33 * sizeof(vector128) +
 813                                                sizeof(u32)),
 814                                            (void __user *) data);
 815
 816         case PTRACE_SETVRREGS:
 817                 return copy_regset_from_user(child, &user_ppc_native_view,
 818                                              REGSET_VMX,
 819                                              0, (33 * sizeof(vector128) +
 820                                                  sizeof(u32)),
 821                                              (const void __user *) data);
 822 #endif
 823 #ifdef CONFIG_SPE
 824         case PTRACE_GETEVRREGS:
 825                 /* Get the child spe register state. */
 826                 return copy_regset_to_user(child, &user_ppc_native_view,
 827                                            REGSET_SPE, 0, 35 * sizeof(u32),
 828                                            (void __user *) data);
 829
 830         case PTRACE_SETEVRREGS:
 831                 /* Set the child spe register state. */
 832                 return copy_regset_from_user(child, &user_ppc_native_view,
 833                                              REGSET_SPE, 0, 35 * sizeof(u32),
 834                                              (const void __user *) data);
 835 #endif
 836
 837         /* Old reverse args ptrace callss */
 838         case PPC_PTRACE_GETREGS: /* Get GPRs 0 - 31. */
 839         case PPC_PTRACE_SETREGS: /* Set GPRs 0 - 31. */
 840         case PPC_PTRACE_GETFPREGS: /* Get FPRs 0 - 31. */
 841         case PPC_PTRACE_SETFPREGS: /* Get FPRs 0 - 31. */
 842                 ret = arch_ptrace_old(child, request, addr, data);
 843                 break;
 844
 845         default:
 846                 ret = ptrace_request(child, request, addr, data);
 847                 break;
 848         }
 849         return ret;
 850 }
 851
 852 static void do_syscall_trace(void)
 853 {
 854         /* the 0x80 provides a way for the tracing parent to distinguish
 855            between a syscall stop and SIGTRAP delivery */
 856         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
 857                                  ? 0x80 : 0));
 858
 859         /*
 860          * this isn't the same as continuing with a signal, but it will do
 861          * for normal use.  strace only continues with a signal if the
 862          * stopping signal is not SIGTRAP.  -brl
 863          */
 864         if (current->exit_code) {
 865                 send_sig(current->exit_code, current, 1);
 866                 current->exit_code = 0;
 867         }
 868 }
 869
 870 void do_syscall_trace_enter(struct pt_regs *regs)
 871 {
 872         secure_computing(regs->gpr[0]);
 873
 874         if (test_thread_flag(TIF_SYSCALL_TRACE)
 875             && (current->ptrace & PT_PTRACED))
 876                 do_syscall_trace();
 877
 878         if (unlikely(current->audit_context)) {
 879 #ifdef CONFIG_PPC64
 880                 if (!test_thread_flag(TIF_32BIT))
 881                         audit_syscall_entry(AUDIT_ARCH_PPC64,
 882                                             regs->gpr[0],
 883                                             regs->gpr[3], regs->gpr[4],
 884                                             regs->gpr[5], regs->gpr[6]);
 885                 else
 886 #endif
 887                         audit_syscall_entry(AUDIT_ARCH_PPC,
 888                                             regs->gpr[0],
 889                                             regs->gpr[3] & 0xffffffff,
 890                                             regs->gpr[4] & 0xffffffff,
 891                                             regs->gpr[5] & 0xffffffff,
 892                                             regs->gpr[6] & 0xffffffff);
 893         }
 894 }
 895
 896 void do_syscall_trace_leave(struct pt_regs *regs)
 897 {
 898         if (unlikely(current->audit_context))
 899                 audit_syscall_exit((regs->ccr&0x10000000)?AUDITSC_FAILURE:AUDITSC_SUCCESS,
 900                                    regs->result);
 901
 902         if ((test_thread_flag(TIF_SYSCALL_TRACE)
 903              || test_thread_flag(TIF_SINGLESTEP))
 904             && (current->ptrace & PT_PTRACED))
 905                 do_syscall_trace();
 906 }