arch/s390/kernel/ptrace.c

   1 /*
   2  *  arch/s390/kernel/ptrace.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Based on PowerPC version
  10  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  11  *
  12  *  Derived from "arch/m68k/kernel/ptrace.c"
  13  *  Copyright (C) 1994 by Hamish Macdonald
  14  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
  15  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  16  *
  17  * Modified by Cort Dougan (cort@cs.nmt.edu)
  18  *
  19  *
  20  * This file is subject to the terms and conditions of the GNU General
  21  * Public License.  See the file README.legal in the main directory of
  22  * this archive for more details.
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/sched.h>
  27 #include <linux/mm.h>
  28 #include <linux/smp.h>
  29 #include <linux/smp_lock.h>
  30 #include <linux/errno.h>
  31 #include <linux/ptrace.h>
  32 #include <linux/user.h>
  33 #include <linux/security.h>
  34 #include <linux/audit.h>
  35 #include <linux/signal.h>
  36 #include <linux/elf.h>
  37 #include <linux/regset.h>
  38
  39 #include <asm/segment.h>
  40 #include <asm/page.h>
  41 #include <asm/pgtable.h>
  42 #include <asm/pgalloc.h>
  43 #include <asm/system.h>
  44 #include <asm/uaccess.h>
  45 #include <asm/unistd.h>
  46 #include "entry.h"
  47
  48 #ifdef CONFIG_COMPAT
  49 #include "compat_ptrace.h"
  50 #endif
  51
  52 enum s390_regset {
  53         REGSET_GENERAL,
  54         REGSET_FP,
  55 };
  56
  57 static void
  58 FixPerRegisters(struct task_struct *task)
  59 {
  60         struct pt_regs *regs;
  61         per_struct *per_info;
  62
  63         regs = task_pt_regs(task);
  64         per_info = (per_struct *) &task->thread.per_info;
  65         per_info->control_regs.bits.em_instruction_fetch =
  66                 per_info->single_step | per_info->instruction_fetch;
  67
  68         if (per_info->single_step) {
  69                 per_info->control_regs.bits.starting_addr = 0;
  70 #ifdef CONFIG_COMPAT
  71                 if (test_thread_flag(TIF_31BIT))
  72                         per_info->control_regs.bits.ending_addr = 0x7fffffffUL;
  73                 else
  74 #endif
  75                         per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN;
  76         } else {
  77                 per_info->control_regs.bits.starting_addr =
  78                         per_info->starting_addr;
  79                 per_info->control_regs.bits.ending_addr =
  80                         per_info->ending_addr;
  81         }
  82         /*
  83          * if any of the control reg tracing bits are on
  84          * we switch on per in the psw
  85          */
  86         if (per_info->control_regs.words.cr[0] & PER_EM_MASK)
  87                 regs->psw.mask |= PSW_MASK_PER;
  88         else
  89                 regs->psw.mask &= ~PSW_MASK_PER;
  90
  91         if (per_info->control_regs.bits.em_storage_alteration)
  92                 per_info->control_regs.bits.storage_alt_space_ctl = 1;
  93         else
  94                 per_info->control_regs.bits.storage_alt_space_ctl = 0;
  95 }
  96
  97 void user_enable_single_step(struct task_struct *task)
  98 {
  99         task->thread.per_info.single_step = 1;
 100         FixPerRegisters(task);
 101 }
 102
 103 void user_disable_single_step(struct task_struct *task)
 104 {
 105         task->thread.per_info.single_step = 0;
 106         FixPerRegisters(task);
 107 }
 108
 109 /*
 110  * Called by kernel/ptrace.c when detaching..
 111  *
 112  * Make sure single step bits etc are not set.
 113  */
 114 void
 115 ptrace_disable(struct task_struct *child)
 116 {
 117         /* make sure the single step bit is not set. */
 118         user_disable_single_step(child);
 119 }
 120
 121 #ifndef CONFIG_64BIT
 122 # define __ADDR_MASK 3
 123 #else
 124 # define __ADDR_MASK 7
 125 #endif
 126
 127 /*
 128  * Read the word at offset addr from the user area of a process. The
 129  * trouble here is that the information is littered over different
 130  * locations. The process registers are found on the kernel stack,
 131  * the floating point stuff and the trace settings are stored in
 132  * the task structure. In addition the different structures in
 133  * struct user contain pad bytes that should be read as zeroes.
 134  * Lovely...
 135  */
 136 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 137 {
 138         struct user *dummy = NULL;
 139         addr_t offset, tmp;
 140
 141         if (addr < (addr_t) &dummy->regs.acrs) {
 142                 /*
 143                  * psw and gprs are stored on the stack
 144                  */
 145                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 146                 if (addr == (addr_t) &dummy->regs.psw.mask)
 147                         /* Remove per bit from user psw. */
 148                         tmp &= ~PSW_MASK_PER;
 149
 150         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 151                 /*
 152                  * access registers are stored in the thread structure
 153                  */
 154                 offset = addr - (addr_t) &dummy->regs.acrs;
 155 #ifdef CONFIG_64BIT
 156                 /*
 157                  * Very special case: old & broken 64 bit gdb reading
 158                  * from acrs[15]. Result is a 64 bit value. Read the
 159                  * 32 bit acrs[15] value and shift it by 32. Sick...
 160                  */
 161                 if (addr == (addr_t) &dummy->regs.acrs[15])
 162                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 163                 else
 164 #endif
 165                 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 166
 167         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 168                 /*
 169                  * orig_gpr2 is stored on the kernel stack
 170                  */
 171                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 172
 173         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 174                 /*
 175                  * floating point regs. are stored in the thread structure
 176                  */
 177                 offset = addr - (addr_t) &dummy->regs.fp_regs;
 178                 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
 179                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
 180                         tmp &= (unsigned long) FPC_VALID_MASK
 181                                 << (BITS_PER_LONG - 32);
 182
 183         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 184                 /*
 185                  * per_info is found in the thread structure
 186                  */
 187                 offset = addr - (addr_t) &dummy->regs.per_info;
 188                 tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset);
 189
 190         } else
 191                 tmp = 0;
 192
 193         return tmp;
 194 }
 195
 196 static int
 197 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 198 {
 199         struct user *dummy = NULL;
 200         addr_t tmp, mask;
 201
 202         /*
 203          * Stupid gdb peeks/pokes the access registers in 64 bit with
 204          * an alignment of 4. Programmers from hell...
 205          */
 206         mask = __ADDR_MASK;
 207 #ifdef CONFIG_64BIT
 208         if (addr >= (addr_t) &dummy->regs.acrs &&
 209             addr < (addr_t) &dummy->regs.orig_gpr2)
 210                 mask = 3;
 211 #endif
 212         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 213                 return -EIO;
 214
 215         tmp = __peek_user(child, addr);
 216         return put_user(tmp, (addr_t __user *) data);
 217 }
 218
 219 /*
 220  * Write a word to the user area of a process at location addr. This
 221  * operation does have an additional problem compared to peek_user.
 222  * Stores to the program status word and on the floating point
 223  * control register needs to get checked for validity.
 224  */
 225 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 226 {
 227         struct user *dummy = NULL;
 228         addr_t offset;
 229
 230         if (addr < (addr_t) &dummy->regs.acrs) {
 231                 /*
 232                  * psw and gprs are stored on the stack
 233                  */
 234                 if (addr == (addr_t) &dummy->regs.psw.mask &&
 235 #ifdef CONFIG_COMPAT
 236                     data != PSW_MASK_MERGE(psw_user32_bits, data) &&
 237 #endif
 238                     data != PSW_MASK_MERGE(psw_user_bits, data))
 239                         /* Invalid psw mask. */
 240                         return -EINVAL;
 241 #ifndef CONFIG_64BIT
 242                 if (addr == (addr_t) &dummy->regs.psw.addr)
 243                         /* I'd like to reject addresses without the
 244                            high order bit but older gdb's rely on it */
 245                         data |= PSW_ADDR_AMODE;
 246 #endif
 247                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 248
 249         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 250                 /*
 251                  * access registers are stored in the thread structure
 252                  */
 253                 offset = addr - (addr_t) &dummy->regs.acrs;
 254 #ifdef CONFIG_64BIT
 255                 /*
 256                  * Very special case: old & broken 64 bit gdb writing
 257                  * to acrs[15] with a 64 bit value. Ignore the lower
 258                  * half of the value and write the upper 32 bit to
 259                  * acrs[15]. Sick...
 260                  */
 261                 if (addr == (addr_t) &dummy->regs.acrs[15])
 262                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 263                 else
 264 #endif
 265                 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 266
 267         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 268                 /*
 269                  * orig_gpr2 is stored on the kernel stack
 270                  */
 271                 task_pt_regs(child)->orig_gpr2 = data;
 272
 273         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 274                 /*
 275                  * floating point regs. are stored in the thread structure
 276                  */
 277                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
 278                     (data & ~((unsigned long) FPC_VALID_MASK
 279                               << (BITS_PER_LONG - 32))) != 0)
 280                         return -EINVAL;
 281                 offset = addr - (addr_t) &dummy->regs.fp_regs;
 282                 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
 283
 284         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 285                 /*
 286                  * per_info is found in the thread structure
 287                  */
 288                 offset = addr - (addr_t) &dummy->regs.per_info;
 289                 *(addr_t *)((addr_t) &child->thread.per_info + offset) = data;
 290
 291         }
 292
 293         FixPerRegisters(child);
 294         return 0;
 295 }
 296
 297 static int
 298 poke_user(struct task_struct *child, addr_t addr, addr_t data)
 299 {
 300         struct user *dummy = NULL;
 301         addr_t mask;
 302
 303         /*
 304          * Stupid gdb peeks/pokes the access registers in 64 bit with
 305          * an alignment of 4. Programmers from hell indeed...
 306          */
 307         mask = __ADDR_MASK;
 308 #ifdef CONFIG_64BIT
 309         if (addr >= (addr_t) &dummy->regs.acrs &&
 310             addr < (addr_t) &dummy->regs.orig_gpr2)
 311                 mask = 3;
 312 #endif
 313         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 314                 return -EIO;
 315
 316         return __poke_user(child, addr, data);
 317 }
 318
 319 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 320 {
 321         ptrace_area parea;
 322         int copied, ret;
 323
 324         switch (request) {
 325         case PTRACE_PEEKTEXT:
 326         case PTRACE_PEEKDATA:
 327                 /* Remove high order bit from address (only for 31 bit). */
 328                 addr &= PSW_ADDR_INSN;
 329                 /* read word at location addr. */
 330                 return generic_ptrace_peekdata(child, addr, data);
 331
 332         case PTRACE_PEEKUSR:
 333                 /* read the word at location addr in the USER area. */
 334                 return peek_user(child, addr, data);
 335
 336         case PTRACE_POKETEXT:
 337         case PTRACE_POKEDATA:
 338                 /* Remove high order bit from address (only for 31 bit). */
 339                 addr &= PSW_ADDR_INSN;
 340                 /* write the word at location addr. */
 341                 return generic_ptrace_pokedata(child, addr, data);
 342
 343         case PTRACE_POKEUSR:
 344                 /* write the word at location addr in the USER area */
 345                 return poke_user(child, addr, data);
 346
 347         case PTRACE_PEEKUSR_AREA:
 348         case PTRACE_POKEUSR_AREA:
 349                 if (copy_from_user(&parea, (void __force __user *) addr,
 350                                                         sizeof(parea)))
 351                         return -EFAULT;
 352                 addr = parea.kernel_addr;
 353                 data = parea.process_addr;
 354                 copied = 0;
 355                 while (copied < parea.len) {
 356                         if (request == PTRACE_PEEKUSR_AREA)
 357                                 ret = peek_user(child, addr, data);
 358                         else {
 359                                 addr_t utmp;
 360                                 if (get_user(utmp,
 361                                              (addr_t __force __user *) data))
 362                                         return -EFAULT;
 363                                 ret = poke_user(child, addr, utmp);
 364                         }
 365                         if (ret)
 366                                 return ret;
 367                         addr += sizeof(unsigned long);
 368                         data += sizeof(unsigned long);
 369                         copied += sizeof(unsigned long);
 370                 }
 371                 return 0;
 372         }
 373         return ptrace_request(child, request, addr, data);
 374 }
 375
 376 #ifdef CONFIG_COMPAT
 377 /*
 378  * Now the fun part starts... a 31 bit program running in the
 379  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 380  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 381  * to handle, the difference to the 64 bit versions of the requests
 382  * is that the access is done in multiples of 4 byte instead of
 383  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 384  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 385  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 386  * is a 31 bit program too, the content of struct user can be
 387  * emulated. A 31 bit program peeking into the struct user of
 388  * a 64 bit program is a no-no.
 389  */
 390
 391 /*
 392  * Same as peek_user but for a 31 bit program.
 393  */
 394 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 395 {
 396         struct user32 *dummy32 = NULL;
 397         per_struct32 *dummy_per32 = NULL;
 398         addr_t offset;
 399         __u32 tmp;
 400
 401         if (addr < (addr_t) &dummy32->regs.acrs) {
 402                 /*
 403                  * psw and gprs are stored on the stack
 404                  */
 405                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 406                         /* Fake a 31 bit psw mask. */
 407                         tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
 408                         tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
 409                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 410                         /* Fake a 31 bit psw address. */
 411                         tmp = (__u32) task_pt_regs(child)->psw.addr |
 412                                 PSW32_ADDR_AMODE31;
 413                 } else {
 414                         /* gpr 0-15 */
 415                         tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
 416                                          addr*2 + 4);
 417                 }
 418         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 419                 /*
 420                  * access registers are stored in the thread structure
 421                  */
 422                 offset = addr - (addr_t) &dummy32->regs.acrs;
 423                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 424
 425         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 426                 /*
 427                  * orig_gpr2 is stored on the kernel stack
 428                  */
 429                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 430
 431         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 432                 /*
 433                  * floating point regs. are stored in the thread structure
 434                  */
 435                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
 436                 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
 437
 438         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 439                 /*
 440                  * per_info is found in the thread structure
 441                  */
 442                 offset = addr - (addr_t) &dummy32->regs.per_info;
 443                 /* This is magic. See per_struct and per_struct32. */
 444                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
 445                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
 446                     (offset >= (addr_t) &dummy_per32->starting_addr &&
 447                      offset <= (addr_t) &dummy_per32->ending_addr) ||
 448                     offset == (addr_t) &dummy_per32->lowcore.words.address)
 449                         offset = offset*2 + 4;
 450                 else
 451                         offset = offset*2;
 452                 tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset);
 453
 454         } else
 455                 tmp = 0;
 456
 457         return tmp;
 458 }
 459
 460 static int peek_user_compat(struct task_struct *child,
 461                             addr_t addr, addr_t data)
 462 {
 463         __u32 tmp;
 464
 465         if (!test_thread_flag(TIF_31BIT) ||
 466             (addr & 3) || addr > sizeof(struct user) - 3)
 467                 return -EIO;
 468
 469         tmp = __peek_user_compat(child, addr);
 470         return put_user(tmp, (__u32 __user *) data);
 471 }
 472
 473 /*
 474  * Same as poke_user but for a 31 bit program.
 475  */
 476 static int __poke_user_compat(struct task_struct *child,
 477                               addr_t addr, addr_t data)
 478 {
 479         struct user32 *dummy32 = NULL;
 480         per_struct32 *dummy_per32 = NULL;
 481         __u32 tmp = (__u32) data;
 482         addr_t offset;
 483
 484         if (addr < (addr_t) &dummy32->regs.acrs) {
 485                 /*
 486                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 487                  */
 488                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 489                         /* Build a 64 bit psw mask from 31 bit mask. */
 490                         if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
 491                                 /* Invalid psw mask. */
 492                                 return -EINVAL;
 493                         task_pt_regs(child)->psw.mask =
 494                                 PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
 495                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 496                         /* Build a 64 bit psw address from 31 bit address. */
 497                         task_pt_regs(child)->psw.addr =
 498                                 (__u64) tmp & PSW32_ADDR_INSN;
 499                 } else {
 500                         /* gpr 0-15 */
 501                         *(__u32*)((addr_t) &task_pt_regs(child)->psw
 502                                   + addr*2 + 4) = tmp;
 503                 }
 504         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 505                 /*
 506                  * access registers are stored in the thread structure
 507                  */
 508                 offset = addr - (addr_t) &dummy32->regs.acrs;
 509                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 510
 511         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 512                 /*
 513                  * orig_gpr2 is stored on the kernel stack
 514                  */
 515                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 516
 517         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 518                 /*
 519                  * floating point regs. are stored in the thread structure
 520                  */
 521                 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
 522                     (tmp & ~FPC_VALID_MASK) != 0)
 523                         /* Invalid floating point control. */
 524                         return -EINVAL;
 525                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
 526                 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
 527
 528         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 529                 /*
 530                  * per_info is found in the thread structure.
 531                  */
 532                 offset = addr - (addr_t) &dummy32->regs.per_info;
 533                 /*
 534                  * This is magic. See per_struct and per_struct32.
 535                  * By incident the offsets in per_struct are exactly
 536                  * twice the offsets in per_struct32 for all fields.
 537                  * The 8 byte fields need special handling though,
 538                  * because the second half (bytes 4-7) is needed and
 539                  * not the first half.
 540                  */
 541                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
 542                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
 543                     (offset >= (addr_t) &dummy_per32->starting_addr &&
 544                      offset <= (addr_t) &dummy_per32->ending_addr) ||
 545                     offset == (addr_t) &dummy_per32->lowcore.words.address)
 546                         offset = offset*2 + 4;
 547                 else
 548                         offset = offset*2;
 549                 *(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp;
 550
 551         }
 552
 553         FixPerRegisters(child);
 554         return 0;
 555 }
 556
 557 static int poke_user_compat(struct task_struct *child,
 558                             addr_t addr, addr_t data)
 559 {
 560         if (!test_thread_flag(TIF_31BIT) ||
 561             (addr & 3) || addr > sizeof(struct user32) - 3)
 562                 return -EIO;
 563
 564         return __poke_user_compat(child, addr, data);
 565 }
 566
 567 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 568                         compat_ulong_t caddr, compat_ulong_t cdata)
 569 {
 570         unsigned long addr = caddr;
 571         unsigned long data = cdata;
 572         ptrace_area_emu31 parea;
 573         int copied, ret;
 574
 575         switch (request) {
 576         case PTRACE_PEEKUSR:
 577                 /* read the word at location addr in the USER area. */
 578                 return peek_user_compat(child, addr, data);
 579
 580         case PTRACE_POKEUSR:
 581                 /* write the word at location addr in the USER area */
 582                 return poke_user_compat(child, addr, data);
 583
 584         case PTRACE_PEEKUSR_AREA:
 585         case PTRACE_POKEUSR_AREA:
 586                 if (copy_from_user(&parea, (void __force __user *) addr,
 587                                                         sizeof(parea)))
 588                         return -EFAULT;
 589                 addr = parea.kernel_addr;
 590                 data = parea.process_addr;
 591                 copied = 0;
 592                 while (copied < parea.len) {
 593                         if (request == PTRACE_PEEKUSR_AREA)
 594                                 ret = peek_user_compat(child, addr, data);
 595                         else {
 596                                 __u32 utmp;
 597                                 if (get_user(utmp,
 598                                              (__u32 __force __user *) data))
 599                                         return -EFAULT;
 600                                 ret = poke_user_compat(child, addr, utmp);
 601                         }
 602                         if (ret)
 603                                 return ret;
 604                         addr += sizeof(unsigned int);
 605                         data += sizeof(unsigned int);
 606                         copied += sizeof(unsigned int);
 607                 }
 608                 return 0;
 609         }
 610         return compat_ptrace_request(child, request, addr, data);
 611 }
 612 #endif
 613
 614 asmlinkage void
 615 syscall_trace(struct pt_regs *regs, int entryexit)
 616 {
 617         if (unlikely(current->audit_context) && entryexit)
 618                 audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);
 619
 620         if (!test_thread_flag(TIF_SYSCALL_TRACE))
 621                 goto out;
 622         if (!(current->ptrace & PT_PTRACED))
 623                 goto out;
 624         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
 625                                  ? 0x80 : 0));
 626
 627         /*
 628          * If the debuffer has set an invalid system call number,
 629          * we prepare to skip the system call restart handling.
 630          */
 631         if (!entryexit && regs->gprs[2] >= NR_syscalls)
 632                 regs->trap = -1;
 633
 634         /*
 635          * this isn't the same as continuing with a signal, but it will do
 636          * for normal use.  strace only continues with a signal if the
 637          * stopping signal is not SIGTRAP.  -brl
 638          */
 639         if (current->exit_code) {
 640                 send_sig(current->exit_code, current, 1);
 641                 current->exit_code = 0;
 642         }
 643  out:
 644         if (unlikely(current->audit_context) && !entryexit)
 645                 audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X,
 646                                     regs->gprs[2], regs->orig_gpr2, regs->gprs[3],
 647                                     regs->gprs[4], regs->gprs[5]);
 648 }
 649
 650 /*
 651  * user_regset definitions.
 652  */
 653
 654 static int s390_regs_get(struct task_struct *target,
 655                          const struct user_regset *regset,
 656                          unsigned int pos, unsigned int count,
 657                          void *kbuf, void __user *ubuf)
 658 {
 659         if (target == current)
 660                 save_access_regs(target->thread.acrs);
 661
 662         if (kbuf) {
 663                 unsigned long *k = kbuf;
 664                 while (count > 0) {
 665                         *k++ = __peek_user(target, pos);
 666                         count -= sizeof(*k);
 667                         pos += sizeof(*k);
 668                 }
 669         } else {
 670                 unsigned long __user *u = ubuf;
 671                 while (count > 0) {
 672                         if (__put_user(__peek_user(target, pos), u++))
 673                                 return -EFAULT;
 674                         count -= sizeof(*u);
 675                         pos += sizeof(*u);
 676                 }
 677         }
 678         return 0;
 679 }
 680
 681 static int s390_regs_set(struct task_struct *target,
 682                          const struct user_regset *regset,
 683                          unsigned int pos, unsigned int count,
 684                          const void *kbuf, const void __user *ubuf)
 685 {
 686         int rc = 0;
 687
 688         if (target == current)
 689                 save_access_regs(target->thread.acrs);
 690
 691         if (kbuf) {
 692                 const unsigned long *k = kbuf;
 693                 while (count > 0 && !rc) {
 694                         rc = __poke_user(target, pos, *k++);
 695                         count -= sizeof(*k);
 696                         pos += sizeof(*k);
 697                 }
 698         } else {
 699                 const unsigned long  __user *u = ubuf;
 700                 while (count > 0 && !rc) {
 701                         unsigned long word;
 702                         rc = __get_user(word, u++);
 703                         if (rc)
 704                                 break;
 705                         rc = __poke_user(target, pos, word);
 706                         count -= sizeof(*u);
 707                         pos += sizeof(*u);
 708                 }
 709         }
 710
 711         if (rc == 0 && target == current)
 712                 restore_access_regs(target->thread.acrs);
 713
 714         return rc;
 715 }
 716
 717 static int s390_fpregs_get(struct task_struct *target,
 718                            const struct user_regset *regset, unsigned int pos,
 719                            unsigned int count, void *kbuf, void __user *ubuf)
 720 {
 721         if (target == current)
 722                 save_fp_regs(&target->thread.fp_regs);
 723
 724         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 725                                    &target->thread.fp_regs, 0, -1);
 726 }
 727
 728 static int s390_fpregs_set(struct task_struct *target,
 729                            const struct user_regset *regset, unsigned int pos,
 730                            unsigned int count, const void *kbuf,
 731                            const void __user *ubuf)
 732 {
 733         int rc = 0;
 734
 735         if (target == current)
 736                 save_fp_regs(&target->thread.fp_regs);
 737
 738         /* If setting FPC, must validate it first. */
 739         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 740                 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
 741                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
 742                                         0, offsetof(s390_fp_regs, fprs));
 743                 if (rc)
 744                         return rc;
 745                 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
 746                         return -EINVAL;
 747                 target->thread.fp_regs.fpc = fpc[0];
 748         }
 749
 750         if (rc == 0 && count > 0)
 751                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 752                                         target->thread.fp_regs.fprs,
 753                                         offsetof(s390_fp_regs, fprs), -1);
 754
 755         if (rc == 0 && target == current)
 756                 restore_fp_regs(&target->thread.fp_regs);
 757
 758         return rc;
 759 }
 760
 761 static const struct user_regset s390_regsets[] = {
 762         [REGSET_GENERAL] = {
 763                 .core_note_type = NT_PRSTATUS,
 764                 .n = sizeof(s390_regs) / sizeof(long),
 765                 .size = sizeof(long),
 766                 .align = sizeof(long),
 767                 .get = s390_regs_get,
 768                 .set = s390_regs_set,
 769         },
 770         [REGSET_FP] = {
 771                 .core_note_type = NT_PRFPREG,
 772                 .n = sizeof(s390_fp_regs) / sizeof(long),
 773                 .size = sizeof(long),
 774                 .align = sizeof(long),
 775                 .get = s390_fpregs_get,
 776                 .set = s390_fpregs_set,
 777         },
 778 };
 779
 780 static const struct user_regset_view user_s390_view = {
 781         .name = UTS_MACHINE,
 782         .e_machine = EM_S390,
 783         .regsets = s390_regsets,
 784         .n = ARRAY_SIZE(s390_regsets)
 785 };
 786
 787 #ifdef CONFIG_COMPAT
 788 static int s390_compat_regs_get(struct task_struct *target,
 789                                 const struct user_regset *regset,
 790                                 unsigned int pos, unsigned int count,
 791                                 void *kbuf, void __user *ubuf)
 792 {
 793         if (target == current)
 794                 save_access_regs(target->thread.acrs);
 795
 796         if (kbuf) {
 797                 compat_ulong_t *k = kbuf;
 798                 while (count > 0) {
 799                         *k++ = __peek_user_compat(target, pos);
 800                         count -= sizeof(*k);
 801                         pos += sizeof(*k);
 802                 }
 803         } else {
 804                 compat_ulong_t __user *u = ubuf;
 805                 while (count > 0) {
 806                         if (__put_user(__peek_user_compat(target, pos), u++))
 807                                 return -EFAULT;
 808                         count -= sizeof(*u);
 809                         pos += sizeof(*u);
 810                 }
 811         }
 812         return 0;
 813 }
 814
 815 static int s390_compat_regs_set(struct task_struct *target,
 816                                 const struct user_regset *regset,
 817                                 unsigned int pos, unsigned int count,
 818                                 const void *kbuf, const void __user *ubuf)
 819 {
 820         int rc = 0;
 821
 822         if (target == current)
 823                 save_access_regs(target->thread.acrs);
 824
 825         if (kbuf) {
 826                 const compat_ulong_t *k = kbuf;
 827                 while (count > 0 && !rc) {
 828                         rc = __poke_user_compat(target, pos, *k++);
 829                         count -= sizeof(*k);
 830                         pos += sizeof(*k);
 831                 }
 832         } else {
 833                 const compat_ulong_t  __user *u = ubuf;
 834                 while (count > 0 && !rc) {
 835                         compat_ulong_t word;
 836                         rc = __get_user(word, u++);
 837                         if (rc)
 838                                 break;
 839                         rc = __poke_user_compat(target, pos, word);
 840                         count -= sizeof(*u);
 841                         pos += sizeof(*u);
 842                 }
 843         }
 844
 845         if (rc == 0 && target == current)
 846                 restore_access_regs(target->thread.acrs);
 847
 848         return rc;
 849 }
 850
 851 static const struct user_regset s390_compat_regsets[] = {
 852         [REGSET_GENERAL] = {
 853                 .core_note_type = NT_PRSTATUS,
 854                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
 855                 .size = sizeof(compat_long_t),
 856                 .align = sizeof(compat_long_t),
 857                 .get = s390_compat_regs_get,
 858                 .set = s390_compat_regs_set,
 859         },
 860         [REGSET_FP] = {
 861                 .core_note_type = NT_PRFPREG,
 862                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
 863                 .size = sizeof(compat_long_t),
 864                 .align = sizeof(compat_long_t),
 865                 .get = s390_fpregs_get,
 866                 .set = s390_fpregs_set,
 867         },
 868 };
 869
 870 static const struct user_regset_view user_s390_compat_view = {
 871         .name = "s390",
 872         .e_machine = EM_S390,
 873         .regsets = s390_compat_regsets,
 874         .n = ARRAY_SIZE(s390_compat_regsets)
 875 };
 876 #endif
 877
 878 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 879 {
 880 #ifdef CONFIG_COMPAT
 881         if (test_tsk_thread_flag(task, TIF_31BIT))
 882                 return &user_s390_compat_view;
 883 #endif
 884         return &user_s390_view;
 885 }