arch/s390/kernel/ptrace.c

   1 /*
   2  *  Ptrace user space interface.
   3  *
   4  *    Copyright IBM Corp. 1999, 2010
   5  *    Author(s): Denis Joseph Barrow
   6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/sched.h>
  11 #include <linux/mm.h>
  12 #include <linux/smp.h>
  13 #include <linux/errno.h>
  14 #include <linux/ptrace.h>
  15 #include <linux/user.h>
  16 #include <linux/security.h>
  17 #include <linux/audit.h>
  18 #include <linux/signal.h>
  19 #include <linux/elf.h>
  20 #include <linux/regset.h>
  21 #include <linux/tracehook.h>
  22 #include <linux/seccomp.h>
  23 #include <linux/compat.h>
  24 #include <trace/syscall.h>
  25 #include <asm/segment.h>
  26 #include <asm/page.h>
  27 #include <asm/pgtable.h>
  28 #include <asm/pgalloc.h>
  29 #include <asm/uaccess.h>
  30 #include <asm/unistd.h>
  31 #include <asm/switch_to.h>
  32 #include "entry.h"
  33
  34 #ifdef CONFIG_COMPAT
  35 #include "compat_ptrace.h"
  36 #endif
  37
  38 #define CREATE_TRACE_POINTS
  39 #include <trace/events/syscalls.h>
  40
  41 void update_cr_regs(struct task_struct *task)
  42 {
  43         struct pt_regs *regs = task_pt_regs(task);
  44         struct thread_struct *thread = &task->thread;
  45         struct per_regs old, new;
  46
  47 #ifdef CONFIG_64BIT
  48         /* Take care of the enable/disable of transactional execution. */
  49         if (MACHINE_HAS_TE || MACHINE_HAS_VX) {
  50                 unsigned long cr, cr_new;
  51
  52                 __ctl_store(cr, 0, 0);
  53                 cr_new = cr;
  54                 if (MACHINE_HAS_TE) {
  55                         /* Set or clear transaction execution TXC bit 8. */
  56                         cr_new |= (1UL << 55);
  57                         if (task->thread.per_flags & PER_FLAG_NO_TE)
  58                                 cr_new &= ~(1UL << 55);
  59                 }
  60                 if (MACHINE_HAS_VX) {
  61                         /* Enable/disable of vector extension */
  62                         cr_new &= ~(1UL << 17);
  63                         if (task->thread.vxrs)
  64                                 cr_new |= (1UL << 17);
  65                 }
  66                 if (cr_new != cr)
  67                         __ctl_load(cr_new, 0, 0);
  68                 if (MACHINE_HAS_TE) {
  69                         /* Set/clear transaction execution TDC bits 62/63. */
  70                         __ctl_store(cr, 2, 2);
  71                         cr_new = cr & ~3UL;
  72                         if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
  73                                 if (task->thread.per_flags &
  74                                     PER_FLAG_TE_ABORT_RAND_TEND)
  75                                         cr_new |= 1UL;
  76                                 else
  77                                         cr_new |= 2UL;
  78                         }
  79                         if (cr_new != cr)
  80                                 __ctl_load(cr_new, 2, 2);
  81                 }
  82         }
  83 #endif
  84         /* Copy user specified PER registers */
  85         new.control = thread->per_user.control;
  86         new.start = thread->per_user.start;
  87         new.end = thread->per_user.end;
  88
  89         /* merge TIF_SINGLE_STEP into user specified PER registers. */
  90         if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
  91             test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
  92                 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
  93                         new.control |= PER_EVENT_BRANCH;
  94                 else
  95                         new.control |= PER_EVENT_IFETCH;
  96 #ifdef CONFIG_64BIT
  97                 new.control |= PER_CONTROL_SUSPENSION;
  98                 new.control |= PER_EVENT_TRANSACTION_END;
  99 #endif
 100                 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
 101                         new.control |= PER_EVENT_IFETCH;
 102                 new.start = 0;
 103                 new.end = PSW_ADDR_INSN;
 104         }
 105
 106         /* Take care of the PER enablement bit in the PSW. */
 107         if (!(new.control & PER_EVENT_MASK)) {
 108                 regs->psw.mask &= ~PSW_MASK_PER;
 109                 return;
 110         }
 111         regs->psw.mask |= PSW_MASK_PER;
 112         __ctl_store(old, 9, 11);
 113         if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
 114                 __ctl_load(new, 9, 11);
 115 }
 116
 117 void user_enable_single_step(struct task_struct *task)
 118 {
 119         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 120         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 121 }
 122
 123 void user_disable_single_step(struct task_struct *task)
 124 {
 125         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 126         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 127 }
 128
 129 void user_enable_block_step(struct task_struct *task)
 130 {
 131         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 132         set_tsk_thread_flag(task, TIF_BLOCK_STEP);
 133 }
 134
 135 /*
 136  * Called by kernel/ptrace.c when detaching..
 137  *
 138  * Clear all debugging related fields.
 139  */
 140 void ptrace_disable(struct task_struct *task)
 141 {
 142         memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 143         memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 144         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 145         clear_pt_regs_flag(task_pt_regs(task), PIF_PER_TRAP);
 146         task->thread.per_flags = 0;
 147 }
 148
 149 #ifndef CONFIG_64BIT
 150 # define __ADDR_MASK 3
 151 #else
 152 # define __ADDR_MASK 7
 153 #endif
 154
 155 static inline unsigned long __peek_user_per(struct task_struct *child,
 156                                             addr_t addr)
 157 {
 158         struct per_struct_kernel *dummy = NULL;
 159
 160         if (addr == (addr_t) &dummy->cr9)
 161                 /* Control bits of the active per set. */
 162                 return test_thread_flag(TIF_SINGLE_STEP) ?
 163                         PER_EVENT_IFETCH : child->thread.per_user.control;
 164         else if (addr == (addr_t) &dummy->cr10)
 165                 /* Start address of the active per set. */
 166                 return test_thread_flag(TIF_SINGLE_STEP) ?
 167                         0 : child->thread.per_user.start;
 168         else if (addr == (addr_t) &dummy->cr11)
 169                 /* End address of the active per set. */
 170                 return test_thread_flag(TIF_SINGLE_STEP) ?
 171                         PSW_ADDR_INSN : child->thread.per_user.end;
 172         else if (addr == (addr_t) &dummy->bits)
 173                 /* Single-step bit. */
 174                 return test_thread_flag(TIF_SINGLE_STEP) ?
 175                         (1UL << (BITS_PER_LONG - 1)) : 0;
 176         else if (addr == (addr_t) &dummy->starting_addr)
 177                 /* Start address of the user specified per set. */
 178                 return child->thread.per_user.start;
 179         else if (addr == (addr_t) &dummy->ending_addr)
 180                 /* End address of the user specified per set. */
 181                 return child->thread.per_user.end;
 182         else if (addr == (addr_t) &dummy->perc_atmid)
 183                 /* PER code, ATMID and AI of the last PER trap */
 184                 return (unsigned long)
 185                         child->thread.per_event.cause << (BITS_PER_LONG - 16);
 186         else if (addr == (addr_t) &dummy->address)
 187                 /* Address of the last PER trap */
 188                 return child->thread.per_event.address;
 189         else if (addr == (addr_t) &dummy->access_id)
 190                 /* Access id of the last PER trap */
 191                 return (unsigned long)
 192                         child->thread.per_event.paid << (BITS_PER_LONG - 8);
 193         return 0;
 194 }
 195
 196 /*
 197  * Read the word at offset addr from the user area of a process. The
 198  * trouble here is that the information is littered over different
 199  * locations. The process registers are found on the kernel stack,
 200  * the floating point stuff and the trace settings are stored in
 201  * the task structure. In addition the different structures in
 202  * struct user contain pad bytes that should be read as zeroes.
 203  * Lovely...
 204  */
 205 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 206 {
 207         struct user *dummy = NULL;
 208         addr_t offset, tmp;
 209
 210         if (addr < (addr_t) &dummy->regs.acrs) {
 211                 /*
 212                  * psw and gprs are stored on the stack
 213                  */
 214                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 215                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 216                         /* Return a clean psw mask. */
 217                         tmp &= PSW_MASK_USER | PSW_MASK_RI;
 218                         tmp |= PSW_USER_BITS;
 219                 }
 220
 221         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 222                 /*
 223                  * access registers are stored in the thread structure
 224                  */
 225                 offset = addr - (addr_t) &dummy->regs.acrs;
 226 #ifdef CONFIG_64BIT
 227                 /*
 228                  * Very special case: old & broken 64 bit gdb reading
 229                  * from acrs[15]. Result is a 64 bit value. Read the
 230                  * 32 bit acrs[15] value and shift it by 32. Sick...
 231                  */
 232                 if (addr == (addr_t) &dummy->regs.acrs[15])
 233                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 234                 else
 235 #endif
 236                 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 237
 238         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 239                 /*
 240                  * orig_gpr2 is stored on the kernel stack
 241                  */
 242                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 243
 244         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 245                 /*
 246                  * prevent reads of padding hole between
 247                  * orig_gpr2 and fp_regs on s390.
 248                  */
 249                 tmp = 0;
 250
 251         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 252                 /*
 253                  * floating point control reg. is in the thread structure
 254                  */
 255                 tmp = child->thread.fp_regs.fpc;
 256                 tmp <<= BITS_PER_LONG - 32;
 257
 258         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 259                 /*
 260                  * floating point regs. are either in child->thread.fp_regs
 261                  * or the child->thread.vxrs array
 262                  */
 263                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 264 #ifdef CONFIG_64BIT
 265                 if (child->thread.vxrs)
 266                         tmp = *(addr_t *)
 267                                ((addr_t) child->thread.vxrs + 2*offset);
 268                 else
 269 #endif
 270                         tmp = *(addr_t *)
 271                                ((addr_t) &child->thread.fp_regs.fprs + offset);
 272
 273         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 274                 /*
 275                  * Handle access to the per_info structure.
 276                  */
 277                 addr -= (addr_t) &dummy->regs.per_info;
 278                 tmp = __peek_user_per(child, addr);
 279
 280         } else
 281                 tmp = 0;
 282
 283         return tmp;
 284 }
 285
 286 static int
 287 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 288 {
 289         addr_t tmp, mask;
 290
 291         /*
 292          * Stupid gdb peeks/pokes the access registers in 64 bit with
 293          * an alignment of 4. Programmers from hell...
 294          */
 295         mask = __ADDR_MASK;
 296 #ifdef CONFIG_64BIT
 297         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 298             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 299                 mask = 3;
 300 #endif
 301         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 302                 return -EIO;
 303
 304         tmp = __peek_user(child, addr);
 305         return put_user(tmp, (addr_t __user *) data);
 306 }
 307
 308 static inline void __poke_user_per(struct task_struct *child,
 309                                    addr_t addr, addr_t data)
 310 {
 311         struct per_struct_kernel *dummy = NULL;
 312
 313         /*
 314          * There are only three fields in the per_info struct that the
 315          * debugger user can write to.
 316          * 1) cr9: the debugger wants to set a new PER event mask
 317          * 2) starting_addr: the debugger wants to set a new starting
 318          *    address to use with the PER event mask.
 319          * 3) ending_addr: the debugger wants to set a new ending
 320          *    address to use with the PER event mask.
 321          * The user specified PER event mask and the start and end
 322          * addresses are used only if single stepping is not in effect.
 323          * Writes to any other field in per_info are ignored.
 324          */
 325         if (addr == (addr_t) &dummy->cr9)
 326                 /* PER event mask of the user specified per set. */
 327                 child->thread.per_user.control =
 328                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 329         else if (addr == (addr_t) &dummy->starting_addr)
 330                 /* Starting address of the user specified per set. */
 331                 child->thread.per_user.start = data;
 332         else if (addr == (addr_t) &dummy->ending_addr)
 333                 /* Ending address of the user specified per set. */
 334                 child->thread.per_user.end = data;
 335 }
 336
 337 /*
 338  * Write a word to the user area of a process at location addr. This
 339  * operation does have an additional problem compared to peek_user.
 340  * Stores to the program status word and on the floating point
 341  * control register needs to get checked for validity.
 342  */
 343 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 344 {
 345         struct user *dummy = NULL;
 346         addr_t offset;
 347
 348         if (addr < (addr_t) &dummy->regs.acrs) {
 349                 /*
 350                  * psw and gprs are stored on the stack
 351                  */
 352                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 353                         unsigned long mask = PSW_MASK_USER;
 354
 355                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 356                         if ((data ^ PSW_USER_BITS) & ~mask)
 357                                 /* Invalid psw mask. */
 358                                 return -EINVAL;
 359                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 360                                 /* Invalid address-space-control bits */
 361                                 return -EINVAL;
 362                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 363                                 /* Invalid addressing mode bits */
 364                                 return -EINVAL;
 365                 }
 366                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 367
 368         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 369                 /*
 370                  * access registers are stored in the thread structure
 371                  */
 372                 offset = addr - (addr_t) &dummy->regs.acrs;
 373 #ifdef CONFIG_64BIT
 374                 /*
 375                  * Very special case: old & broken 64 bit gdb writing
 376                  * to acrs[15] with a 64 bit value. Ignore the lower
 377                  * half of the value and write the upper 32 bit to
 378                  * acrs[15]. Sick...
 379                  */
 380                 if (addr == (addr_t) &dummy->regs.acrs[15])
 381                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 382                 else
 383 #endif
 384                 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 385
 386         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 387                 /*
 388                  * orig_gpr2 is stored on the kernel stack
 389                  */
 390                 task_pt_regs(child)->orig_gpr2 = data;
 391
 392         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 393                 /*
 394                  * prevent writes of padding hole between
 395                  * orig_gpr2 and fp_regs on s390.
 396                  */
 397                 return 0;
 398
 399         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 400                 /*
 401                  * floating point control reg. is in the thread structure
 402                  */
 403                 if ((unsigned int) data != 0 ||
 404                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 405                         return -EINVAL;
 406                 child->thread.fp_regs.fpc = data >> (BITS_PER_LONG - 32);
 407
 408         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 409                 /*
 410                  * floating point regs. are either in child->thread.fp_regs
 411                  * or the child->thread.vxrs array
 412                  */
 413                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 414 #ifdef CONFIG_64BIT
 415                 if (child->thread.vxrs)
 416                         *(addr_t *)((addr_t)
 417                                 child->thread.vxrs + 2*offset) = data;
 418                 else
 419 #endif
 420                         *(addr_t *)((addr_t)
 421                                 &child->thread.fp_regs.fprs + offset) = data;
 422
 423         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 424                 /*
 425                  * Handle access to the per_info structure.
 426                  */
 427                 addr -= (addr_t) &dummy->regs.per_info;
 428                 __poke_user_per(child, addr, data);
 429
 430         }
 431
 432         return 0;
 433 }
 434
 435 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 436 {
 437         addr_t mask;
 438
 439         /*
 440          * Stupid gdb peeks/pokes the access registers in 64 bit with
 441          * an alignment of 4. Programmers from hell indeed...
 442          */
 443         mask = __ADDR_MASK;
 444 #ifdef CONFIG_64BIT
 445         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 446             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 447                 mask = 3;
 448 #endif
 449         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 450                 return -EIO;
 451
 452         return __poke_user(child, addr, data);
 453 }
 454
 455 long arch_ptrace(struct task_struct *child, long request,
 456                  unsigned long addr, unsigned long data)
 457 {
 458         ptrace_area parea;
 459         int copied, ret;
 460
 461         switch (request) {
 462         case PTRACE_PEEKUSR:
 463                 /* read the word at location addr in the USER area. */
 464                 return peek_user(child, addr, data);
 465
 466         case PTRACE_POKEUSR:
 467                 /* write the word at location addr in the USER area */
 468                 return poke_user(child, addr, data);
 469
 470         case PTRACE_PEEKUSR_AREA:
 471         case PTRACE_POKEUSR_AREA:
 472                 if (copy_from_user(&parea, (void __force __user *) addr,
 473                                                         sizeof(parea)))
 474                         return -EFAULT;
 475                 addr = parea.kernel_addr;
 476                 data = parea.process_addr;
 477                 copied = 0;
 478                 while (copied < parea.len) {
 479                         if (request == PTRACE_PEEKUSR_AREA)
 480                                 ret = peek_user(child, addr, data);
 481                         else {
 482                                 addr_t utmp;
 483                                 if (get_user(utmp,
 484                                              (addr_t __force __user *) data))
 485                                         return -EFAULT;
 486                                 ret = poke_user(child, addr, utmp);
 487                         }
 488                         if (ret)
 489                                 return ret;
 490                         addr += sizeof(unsigned long);
 491                         data += sizeof(unsigned long);
 492                         copied += sizeof(unsigned long);
 493                 }
 494                 return 0;
 495         case PTRACE_GET_LAST_BREAK:
 496                 put_user(task_thread_info(child)->last_break,
 497                          (unsigned long __user *) data);
 498                 return 0;
 499         case PTRACE_ENABLE_TE:
 500                 if (!MACHINE_HAS_TE)
 501                         return -EIO;
 502                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 503                 return 0;
 504         case PTRACE_DISABLE_TE:
 505                 if (!MACHINE_HAS_TE)
 506                         return -EIO;
 507                 child->thread.per_flags |= PER_FLAG_NO_TE;
 508                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 509                 return 0;
 510         case PTRACE_TE_ABORT_RAND:
 511                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 512                         return -EIO;
 513                 switch (data) {
 514                 case 0UL:
 515                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 516                         break;
 517                 case 1UL:
 518                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 519                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 520                         break;
 521                 case 2UL:
 522                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 523                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 524                         break;
 525                 default:
 526                         return -EINVAL;
 527                 }
 528                 return 0;
 529         default:
 530                 /* Removing high order bit from addr (only for 31 bit). */
 531                 addr &= PSW_ADDR_INSN;
 532                 return ptrace_request(child, request, addr, data);
 533         }
 534 }
 535
 536 #ifdef CONFIG_COMPAT
 537 /*
 538  * Now the fun part starts... a 31 bit program running in the
 539  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 540  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 541  * to handle, the difference to the 64 bit versions of the requests
 542  * is that the access is done in multiples of 4 byte instead of
 543  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 544  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 545  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 546  * is a 31 bit program too, the content of struct user can be
 547  * emulated. A 31 bit program peeking into the struct user of
 548  * a 64 bit program is a no-no.
 549  */
 550
 551 /*
 552  * Same as peek_user_per but for a 31 bit program.
 553  */
 554 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 555                                            addr_t addr)
 556 {
 557         struct compat_per_struct_kernel *dummy32 = NULL;
 558
 559         if (addr == (addr_t) &dummy32->cr9)
 560                 /* Control bits of the active per set. */
 561                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 562                         PER_EVENT_IFETCH : child->thread.per_user.control;
 563         else if (addr == (addr_t) &dummy32->cr10)
 564                 /* Start address of the active per set. */
 565                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 566                         0 : child->thread.per_user.start;
 567         else if (addr == (addr_t) &dummy32->cr11)
 568                 /* End address of the active per set. */
 569                 return test_thread_flag(TIF_SINGLE_STEP) ?
 570                         PSW32_ADDR_INSN : child->thread.per_user.end;
 571         else if (addr == (addr_t) &dummy32->bits)
 572                 /* Single-step bit. */
 573                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 574                         0x80000000 : 0;
 575         else if (addr == (addr_t) &dummy32->starting_addr)
 576                 /* Start address of the user specified per set. */
 577                 return (__u32) child->thread.per_user.start;
 578         else if (addr == (addr_t) &dummy32->ending_addr)
 579                 /* End address of the user specified per set. */
 580                 return (__u32) child->thread.per_user.end;
 581         else if (addr == (addr_t) &dummy32->perc_atmid)
 582                 /* PER code, ATMID and AI of the last PER trap */
 583                 return (__u32) child->thread.per_event.cause << 16;
 584         else if (addr == (addr_t) &dummy32->address)
 585                 /* Address of the last PER trap */
 586                 return (__u32) child->thread.per_event.address;
 587         else if (addr == (addr_t) &dummy32->access_id)
 588                 /* Access id of the last PER trap */
 589                 return (__u32) child->thread.per_event.paid << 24;
 590         return 0;
 591 }
 592
 593 /*
 594  * Same as peek_user but for a 31 bit program.
 595  */
 596 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 597 {
 598         struct compat_user *dummy32 = NULL;
 599         addr_t offset;
 600         __u32 tmp;
 601
 602         if (addr < (addr_t) &dummy32->regs.acrs) {
 603                 struct pt_regs *regs = task_pt_regs(child);
 604                 /*
 605                  * psw and gprs are stored on the stack
 606                  */
 607                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 608                         /* Fake a 31 bit psw mask. */
 609                         tmp = (__u32)(regs->psw.mask >> 32);
 610                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 611                         tmp |= PSW32_USER_BITS;
 612                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 613                         /* Fake a 31 bit psw address. */
 614                         tmp = (__u32) regs->psw.addr |
 615                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 616                 } else {
 617                         /* gpr 0-15 */
 618                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 619                 }
 620         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 621                 /*
 622                  * access registers are stored in the thread structure
 623                  */
 624                 offset = addr - (addr_t) &dummy32->regs.acrs;
 625                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 626
 627         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 628                 /*
 629                  * orig_gpr2 is stored on the kernel stack
 630                  */
 631                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 632
 633         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 634                 /*
 635                  * prevent reads of padding hole between
 636                  * orig_gpr2 and fp_regs on s390.
 637                  */
 638                 tmp = 0;
 639
 640         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 641                 /*
 642                  * floating point control reg. is in the thread structure
 643                  */
 644                 tmp = child->thread.fp_regs.fpc;
 645
 646         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 647                 /*
 648                  * floating point regs. are either in child->thread.fp_regs
 649                  * or the child->thread.vxrs array
 650                  */
 651                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 652 #ifdef CONFIG_64BIT
 653                 if (child->thread.vxrs)
 654                         tmp = *(__u32 *)
 655                                ((addr_t) child->thread.vxrs + 2*offset);
 656                 else
 657 #endif
 658                         tmp = *(__u32 *)
 659                                ((addr_t) &child->thread.fp_regs.fprs + offset);
 660
 661         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 662                 /*
 663                  * Handle access to the per_info structure.
 664                  */
 665                 addr -= (addr_t) &dummy32->regs.per_info;
 666                 tmp = __peek_user_per_compat(child, addr);
 667
 668         } else
 669                 tmp = 0;
 670
 671         return tmp;
 672 }
 673
 674 static int peek_user_compat(struct task_struct *child,
 675                             addr_t addr, addr_t data)
 676 {
 677         __u32 tmp;
 678
 679         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 680                 return -EIO;
 681
 682         tmp = __peek_user_compat(child, addr);
 683         return put_user(tmp, (__u32 __user *) data);
 684 }
 685
 686 /*
 687  * Same as poke_user_per but for a 31 bit program.
 688  */
 689 static inline void __poke_user_per_compat(struct task_struct *child,
 690                                           addr_t addr, __u32 data)
 691 {
 692         struct compat_per_struct_kernel *dummy32 = NULL;
 693
 694         if (addr == (addr_t) &dummy32->cr9)
 695                 /* PER event mask of the user specified per set. */
 696                 child->thread.per_user.control =
 697                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 698         else if (addr == (addr_t) &dummy32->starting_addr)
 699                 /* Starting address of the user specified per set. */
 700                 child->thread.per_user.start = data;
 701         else if (addr == (addr_t) &dummy32->ending_addr)
 702                 /* Ending address of the user specified per set. */
 703                 child->thread.per_user.end = data;
 704 }
 705
 706 /*
 707  * Same as poke_user but for a 31 bit program.
 708  */
 709 static int __poke_user_compat(struct task_struct *child,
 710                               addr_t addr, addr_t data)
 711 {
 712         struct compat_user *dummy32 = NULL;
 713         __u32 tmp = (__u32) data;
 714         addr_t offset;
 715
 716         if (addr < (addr_t) &dummy32->regs.acrs) {
 717                 struct pt_regs *regs = task_pt_regs(child);
 718                 /*
 719                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 720                  */
 721                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 722                         __u32 mask = PSW32_MASK_USER;
 723
 724                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 725                         /* Build a 64 bit psw mask from 31 bit mask. */
 726                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 727                                 /* Invalid psw mask. */
 728                                 return -EINVAL;
 729                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 730                                 /* Invalid address-space-control bits */
 731                                 return -EINVAL;
 732                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 733                                 (regs->psw.mask & PSW_MASK_BA) |
 734                                 (__u64)(tmp & mask) << 32;
 735                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 736                         /* Build a 64 bit psw address from 31 bit address. */
 737                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 738                         /* Transfer 31 bit amode bit to psw mask. */
 739                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 740                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 741                 } else {
 742                         /* gpr 0-15 */
 743                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 744                 }
 745         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 746                 /*
 747                  * access registers are stored in the thread structure
 748                  */
 749                 offset = addr - (addr_t) &dummy32->regs.acrs;
 750                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 751
 752         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 753                 /*
 754                  * orig_gpr2 is stored on the kernel stack
 755                  */
 756                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 757
 758         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 759                 /*
 760                  * prevent writess of padding hole between
 761                  * orig_gpr2 and fp_regs on s390.
 762                  */
 763                 return 0;
 764
 765         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 766                 /*
 767                  * floating point control reg. is in the thread structure
 768                  */
 769                 if (test_fp_ctl(tmp))
 770                         return -EINVAL;
 771                 child->thread.fp_regs.fpc = data;
 772
 773         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 774                 /*
 775                  * floating point regs. are either in child->thread.fp_regs
 776                  * or the child->thread.vxrs array
 777                  */
 778                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 779 #ifdef CONFIG_64BIT
 780                 if (child->thread.vxrs)
 781                         *(__u32 *)((addr_t)
 782                                 child->thread.vxrs + 2*offset) = tmp;
 783                 else
 784 #endif
 785                         *(__u32 *)((addr_t)
 786                                 &child->thread.fp_regs.fprs + offset) = tmp;
 787
 788         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 789                 /*
 790                  * Handle access to the per_info structure.
 791                  */
 792                 addr -= (addr_t) &dummy32->regs.per_info;
 793                 __poke_user_per_compat(child, addr, data);
 794         }
 795
 796         return 0;
 797 }
 798
 799 static int poke_user_compat(struct task_struct *child,
 800                             addr_t addr, addr_t data)
 801 {
 802         if (!is_compat_task() || (addr & 3) ||
 803             addr > sizeof(struct compat_user) - 3)
 804                 return -EIO;
 805
 806         return __poke_user_compat(child, addr, data);
 807 }
 808
 809 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 810                         compat_ulong_t caddr, compat_ulong_t cdata)
 811 {
 812         unsigned long addr = caddr;
 813         unsigned long data = cdata;
 814         compat_ptrace_area parea;
 815         int copied, ret;
 816
 817         switch (request) {
 818         case PTRACE_PEEKUSR:
 819                 /* read the word at location addr in the USER area. */
 820                 return peek_user_compat(child, addr, data);
 821
 822         case PTRACE_POKEUSR:
 823                 /* write the word at location addr in the USER area */
 824                 return poke_user_compat(child, addr, data);
 825
 826         case PTRACE_PEEKUSR_AREA:
 827         case PTRACE_POKEUSR_AREA:
 828                 if (copy_from_user(&parea, (void __force __user *) addr,
 829                                                         sizeof(parea)))
 830                         return -EFAULT;
 831                 addr = parea.kernel_addr;
 832                 data = parea.process_addr;
 833                 copied = 0;
 834                 while (copied < parea.len) {
 835                         if (request == PTRACE_PEEKUSR_AREA)
 836                                 ret = peek_user_compat(child, addr, data);
 837                         else {
 838                                 __u32 utmp;
 839                                 if (get_user(utmp,
 840                                              (__u32 __force __user *) data))
 841                                         return -EFAULT;
 842                                 ret = poke_user_compat(child, addr, utmp);
 843                         }
 844                         if (ret)
 845                                 return ret;
 846                         addr += sizeof(unsigned int);
 847                         data += sizeof(unsigned int);
 848                         copied += sizeof(unsigned int);
 849                 }
 850                 return 0;
 851         case PTRACE_GET_LAST_BREAK:
 852                 put_user(task_thread_info(child)->last_break,
 853                          (unsigned int __user *) data);
 854                 return 0;
 855         }
 856         return compat_ptrace_request(child, request, addr, data);
 857 }
 858 #endif
 859
 860 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 861 {
 862         long ret = 0;
 863
 864         /* Do the secure computing check first. */
 865         if (secure_computing()) {
 866                 /* seccomp failures shouldn't expose any additional code. */
 867                 ret = -1;
 868                 goto out;
 869         }
 870
 871         /*
 872          * The sysc_tracesys code in entry.S stored the system
 873          * call number to gprs[2].
 874          */
 875         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 876             (tracehook_report_syscall_entry(regs) ||
 877              regs->gprs[2] >= NR_syscalls)) {
 878                 /*
 879                  * Tracing decided this syscall should not happen or the
 880                  * debugger stored an invalid system call number. Skip
 881                  * the system call and the system call restart handling.
 882                  */
 883                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 884                 ret = -1;
 885         }
 886
 887         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 888                 trace_sys_enter(regs, regs->gprs[2]);
 889
 890         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2,
 891                             regs->gprs[3], regs->gprs[4],
 892                             regs->gprs[5]);
 893 out:
 894         return ret ?: regs->gprs[2];
 895 }
 896
 897 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 898 {
 899         audit_syscall_exit(regs);
 900
 901         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 902                 trace_sys_exit(regs, regs->gprs[2]);
 903
 904         if (test_thread_flag(TIF_SYSCALL_TRACE))
 905                 tracehook_report_syscall_exit(regs, 0);
 906 }
 907
 908 /*
 909  * user_regset definitions.
 910  */
 911
 912 static int s390_regs_get(struct task_struct *target,
 913                          const struct user_regset *regset,
 914                          unsigned int pos, unsigned int count,
 915                          void *kbuf, void __user *ubuf)
 916 {
 917         if (target == current)
 918                 save_access_regs(target->thread.acrs);
 919
 920         if (kbuf) {
 921                 unsigned long *k = kbuf;
 922                 while (count > 0) {
 923                         *k++ = __peek_user(target, pos);
 924                         count -= sizeof(*k);
 925                         pos += sizeof(*k);
 926                 }
 927         } else {
 928                 unsigned long __user *u = ubuf;
 929                 while (count > 0) {
 930                         if (__put_user(__peek_user(target, pos), u++))
 931                                 return -EFAULT;
 932                         count -= sizeof(*u);
 933                         pos += sizeof(*u);
 934                 }
 935         }
 936         return 0;
 937 }
 938
 939 static int s390_regs_set(struct task_struct *target,
 940                          const struct user_regset *regset,
 941                          unsigned int pos, unsigned int count,
 942                          const void *kbuf, const void __user *ubuf)
 943 {
 944         int rc = 0;
 945
 946         if (target == current)
 947                 save_access_regs(target->thread.acrs);
 948
 949         if (kbuf) {
 950                 const unsigned long *k = kbuf;
 951                 while (count > 0 && !rc) {
 952                         rc = __poke_user(target, pos, *k++);
 953                         count -= sizeof(*k);
 954                         pos += sizeof(*k);
 955                 }
 956         } else {
 957                 const unsigned long  __user *u = ubuf;
 958                 while (count > 0 && !rc) {
 959                         unsigned long word;
 960                         rc = __get_user(word, u++);
 961                         if (rc)
 962                                 break;
 963                         rc = __poke_user(target, pos, word);
 964                         count -= sizeof(*u);
 965                         pos += sizeof(*u);
 966                 }
 967         }
 968
 969         if (rc == 0 && target == current)
 970                 restore_access_regs(target->thread.acrs);
 971
 972         return rc;
 973 }
 974
 975 static int s390_fpregs_get(struct task_struct *target,
 976                            const struct user_regset *regset, unsigned int pos,
 977                            unsigned int count, void *kbuf, void __user *ubuf)
 978 {
 979         if (target == current) {
 980                 save_fp_ctl(&target->thread.fp_regs.fpc);
 981                 save_fp_regs(target->thread.fp_regs.fprs);
 982         }
 983 #ifdef CONFIG_64BIT
 984         else if (target->thread.vxrs) {
 985                 int i;
 986
 987                 for (i = 0; i < __NUM_VXRS_LOW; i++)
 988                         target->thread.fp_regs.fprs[i] =
 989                                 *(freg_t *)(target->thread.vxrs + i);
 990         }
 991 #endif
 992         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 993                                    &target->thread.fp_regs, 0, -1);
 994 }
 995
 996 static int s390_fpregs_set(struct task_struct *target,
 997                            const struct user_regset *regset, unsigned int pos,
 998                            unsigned int count, const void *kbuf,
 999                            const void __user *ubuf)
1000 {
1001         int rc = 0;
1002
1003         if (target == current) {
1004                 save_fp_ctl(&target->thread.fp_regs.fpc);
1005                 save_fp_regs(target->thread.fp_regs.fprs);
1006         }
1007
1008         /* If setting FPC, must validate it first. */
1009         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
1010                 u32 ufpc[2] = { target->thread.fp_regs.fpc, 0 };
1011                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
1012                                         0, offsetof(s390_fp_regs, fprs));
1013                 if (rc)
1014                         return rc;
1015                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
1016                         return -EINVAL;
1017                 target->thread.fp_regs.fpc = ufpc[0];
1018         }
1019
1020         if (rc == 0 && count > 0)
1021                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1022                                         target->thread.fp_regs.fprs,
1023                                         offsetof(s390_fp_regs, fprs), -1);
1024
1025         if (rc == 0) {
1026                 if (target == current) {
1027                         restore_fp_ctl(&target->thread.fp_regs.fpc);
1028                         restore_fp_regs(target->thread.fp_regs.fprs);
1029                 }
1030 #ifdef CONFIG_64BIT
1031                 else if (target->thread.vxrs) {
1032                         int i;
1033
1034                         for (i = 0; i < __NUM_VXRS_LOW; i++)
1035                                 *(freg_t *)(target->thread.vxrs + i) =
1036                                         target->thread.fp_regs.fprs[i];
1037                 }
1038 #endif
1039         }
1040
1041         return rc;
1042 }
1043
1044 #ifdef CONFIG_64BIT
1045
1046 static int s390_last_break_get(struct task_struct *target,
1047                                const struct user_regset *regset,
1048                                unsigned int pos, unsigned int count,
1049                                void *kbuf, void __user *ubuf)
1050 {
1051         if (count > 0) {
1052                 if (kbuf) {
1053                         unsigned long *k = kbuf;
1054                         *k = task_thread_info(target)->last_break;
1055                 } else {
1056                         unsigned long  __user *u = ubuf;
1057                         if (__put_user(task_thread_info(target)->last_break, u))
1058                                 return -EFAULT;
1059                 }
1060         }
1061         return 0;
1062 }
1063
1064 static int s390_last_break_set(struct task_struct *target,
1065                                const struct user_regset *regset,
1066                                unsigned int pos, unsigned int count,
1067                                const void *kbuf, const void __user *ubuf)
1068 {
1069         return 0;
1070 }
1071
1072 static int s390_tdb_get(struct task_struct *target,
1073                         const struct user_regset *regset,
1074                         unsigned int pos, unsigned int count,
1075                         void *kbuf, void __user *ubuf)
1076 {
1077         struct pt_regs *regs = task_pt_regs(target);
1078         unsigned char *data;
1079
1080         if (!(regs->int_code & 0x200))
1081                 return -ENODATA;
1082         data = target->thread.trap_tdb;
1083         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1084 }
1085
1086 static int s390_tdb_set(struct task_struct *target,
1087                         const struct user_regset *regset,
1088                         unsigned int pos, unsigned int count,
1089                         const void *kbuf, const void __user *ubuf)
1090 {
1091         return 0;
1092 }
1093
1094 static int s390_vxrs_low_get(struct task_struct *target,
1095                              const struct user_regset *regset,
1096                              unsigned int pos, unsigned int count,
1097                              void *kbuf, void __user *ubuf)
1098 {
1099         __u64 vxrs[__NUM_VXRS_LOW];
1100         int i;
1101
1102         if (!MACHINE_HAS_VX)
1103                 return -ENODEV;
1104         if (target->thread.vxrs) {
1105                 if (target == current)
1106                         save_vx_regs(target->thread.vxrs);
1107                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1108                         vxrs[i] = *((__u64 *)(target->thread.vxrs + i) + 1);
1109         } else
1110                 memset(vxrs, 0, sizeof(vxrs));
1111         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1112 }
1113
1114 static int s390_vxrs_low_set(struct task_struct *target,
1115                              const struct user_regset *regset,
1116                              unsigned int pos, unsigned int count,
1117                              const void *kbuf, const void __user *ubuf)
1118 {
1119         __u64 vxrs[__NUM_VXRS_LOW];
1120         int i, rc;
1121
1122         if (!MACHINE_HAS_VX)
1123                 return -ENODEV;
1124         if (!target->thread.vxrs) {
1125                 rc = alloc_vector_registers(target);
1126                 if (rc)
1127                         return rc;
1128         } else if (target == current)
1129                 save_vx_regs(target->thread.vxrs);
1130
1131         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1132         if (rc == 0) {
1133                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1134                         *((__u64 *)(target->thread.vxrs + i) + 1) = vxrs[i];
1135                 if (target == current)
1136                         restore_vx_regs(target->thread.vxrs);
1137         }
1138
1139         return rc;
1140 }
1141
1142 static int s390_vxrs_high_get(struct task_struct *target,
1143                               const struct user_regset *regset,
1144                               unsigned int pos, unsigned int count,
1145                               void *kbuf, void __user *ubuf)
1146 {
1147         __vector128 vxrs[__NUM_VXRS_HIGH];
1148
1149         if (!MACHINE_HAS_VX)
1150                 return -ENODEV;
1151         if (target->thread.vxrs) {
1152                 if (target == current)
1153                         save_vx_regs(target->thread.vxrs);
1154                 memcpy(vxrs, target->thread.vxrs + __NUM_VXRS_LOW,
1155                        sizeof(vxrs));
1156         } else
1157                 memset(vxrs, 0, sizeof(vxrs));
1158         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1159 }
1160
1161 static int s390_vxrs_high_set(struct task_struct *target,
1162                               const struct user_regset *regset,
1163                               unsigned int pos, unsigned int count,
1164                               const void *kbuf, const void __user *ubuf)
1165 {
1166         int rc;
1167
1168         if (!MACHINE_HAS_VX)
1169                 return -ENODEV;
1170         if (!target->thread.vxrs) {
1171                 rc = alloc_vector_registers(target);
1172                 if (rc)
1173                         return rc;
1174         } else if (target == current)
1175                 save_vx_regs(target->thread.vxrs);
1176
1177         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1178                                 target->thread.vxrs + __NUM_VXRS_LOW, 0, -1);
1179         if (rc == 0 && target == current)
1180                 restore_vx_regs(target->thread.vxrs);
1181
1182         return rc;
1183 }
1184
1185 #endif
1186
1187 static int s390_system_call_get(struct task_struct *target,
1188                                 const struct user_regset *regset,
1189                                 unsigned int pos, unsigned int count,
1190                                 void *kbuf, void __user *ubuf)
1191 {
1192         unsigned int *data = &task_thread_info(target)->system_call;
1193         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1194                                    data, 0, sizeof(unsigned int));
1195 }
1196
1197 static int s390_system_call_set(struct task_struct *target,
1198                                 const struct user_regset *regset,
1199                                 unsigned int pos, unsigned int count,
1200                                 const void *kbuf, const void __user *ubuf)
1201 {
1202         unsigned int *data = &task_thread_info(target)->system_call;
1203         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1204                                   data, 0, sizeof(unsigned int));
1205 }
1206
1207 static const struct user_regset s390_regsets[] = {
1208         {
1209                 .core_note_type = NT_PRSTATUS,
1210                 .n = sizeof(s390_regs) / sizeof(long),
1211                 .size = sizeof(long),
1212                 .align = sizeof(long),
1213                 .get = s390_regs_get,
1214                 .set = s390_regs_set,
1215         },
1216         {
1217                 .core_note_type = NT_PRFPREG,
1218                 .n = sizeof(s390_fp_regs) / sizeof(long),
1219                 .size = sizeof(long),
1220                 .align = sizeof(long),
1221                 .get = s390_fpregs_get,
1222                 .set = s390_fpregs_set,
1223         },
1224         {
1225                 .core_note_type = NT_S390_SYSTEM_CALL,
1226                 .n = 1,
1227                 .size = sizeof(unsigned int),
1228                 .align = sizeof(unsigned int),
1229                 .get = s390_system_call_get,
1230                 .set = s390_system_call_set,
1231         },
1232 #ifdef CONFIG_64BIT
1233         {
1234                 .core_note_type = NT_S390_LAST_BREAK,
1235                 .n = 1,
1236                 .size = sizeof(long),
1237                 .align = sizeof(long),
1238                 .get = s390_last_break_get,
1239                 .set = s390_last_break_set,
1240         },
1241         {
1242                 .core_note_type = NT_S390_TDB,
1243                 .n = 1,
1244                 .size = 256,
1245                 .align = 1,
1246                 .get = s390_tdb_get,
1247                 .set = s390_tdb_set,
1248         },
1249         {
1250                 .core_note_type = NT_S390_VXRS_LOW,
1251                 .n = __NUM_VXRS_LOW,
1252                 .size = sizeof(__u64),
1253                 .align = sizeof(__u64),
1254                 .get = s390_vxrs_low_get,
1255                 .set = s390_vxrs_low_set,
1256         },
1257         {
1258                 .core_note_type = NT_S390_VXRS_HIGH,
1259                 .n = __NUM_VXRS_HIGH,
1260                 .size = sizeof(__vector128),
1261                 .align = sizeof(__vector128),
1262                 .get = s390_vxrs_high_get,
1263                 .set = s390_vxrs_high_set,
1264         },
1265 #endif
1266 };
1267
1268 static const struct user_regset_view user_s390_view = {
1269         .name = UTS_MACHINE,
1270         .e_machine = EM_S390,
1271         .regsets = s390_regsets,
1272         .n = ARRAY_SIZE(s390_regsets)
1273 };
1274
1275 #ifdef CONFIG_COMPAT
1276 static int s390_compat_regs_get(struct task_struct *target,
1277                                 const struct user_regset *regset,
1278                                 unsigned int pos, unsigned int count,
1279                                 void *kbuf, void __user *ubuf)
1280 {
1281         if (target == current)
1282                 save_access_regs(target->thread.acrs);
1283
1284         if (kbuf) {
1285                 compat_ulong_t *k = kbuf;
1286                 while (count > 0) {
1287                         *k++ = __peek_user_compat(target, pos);
1288                         count -= sizeof(*k);
1289                         pos += sizeof(*k);
1290                 }
1291         } else {
1292                 compat_ulong_t __user *u = ubuf;
1293                 while (count > 0) {
1294                         if (__put_user(__peek_user_compat(target, pos), u++))
1295                                 return -EFAULT;
1296                         count -= sizeof(*u);
1297                         pos += sizeof(*u);
1298                 }
1299         }
1300         return 0;
1301 }
1302
1303 static int s390_compat_regs_set(struct task_struct *target,
1304                                 const struct user_regset *regset,
1305                                 unsigned int pos, unsigned int count,
1306                                 const void *kbuf, const void __user *ubuf)
1307 {
1308         int rc = 0;
1309
1310         if (target == current)
1311                 save_access_regs(target->thread.acrs);
1312
1313         if (kbuf) {
1314                 const compat_ulong_t *k = kbuf;
1315                 while (count > 0 && !rc) {
1316                         rc = __poke_user_compat(target, pos, *k++);
1317                         count -= sizeof(*k);
1318                         pos += sizeof(*k);
1319                 }
1320         } else {
1321                 const compat_ulong_t  __user *u = ubuf;
1322                 while (count > 0 && !rc) {
1323                         compat_ulong_t word;
1324                         rc = __get_user(word, u++);
1325                         if (rc)
1326                                 break;
1327                         rc = __poke_user_compat(target, pos, word);
1328                         count -= sizeof(*u);
1329                         pos += sizeof(*u);
1330                 }
1331         }
1332
1333         if (rc == 0 && target == current)
1334                 restore_access_regs(target->thread.acrs);
1335
1336         return rc;
1337 }
1338
1339 static int s390_compat_regs_high_get(struct task_struct *target,
1340                                      const struct user_regset *regset,
1341                                      unsigned int pos, unsigned int count,
1342                                      void *kbuf, void __user *ubuf)
1343 {
1344         compat_ulong_t *gprs_high;
1345
1346         gprs_high = (compat_ulong_t *)
1347                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1348         if (kbuf) {
1349                 compat_ulong_t *k = kbuf;
1350                 while (count > 0) {
1351                         *k++ = *gprs_high;
1352                         gprs_high += 2;
1353                         count -= sizeof(*k);
1354                 }
1355         } else {
1356                 compat_ulong_t __user *u = ubuf;
1357                 while (count > 0) {
1358                         if (__put_user(*gprs_high, u++))
1359                                 return -EFAULT;
1360                         gprs_high += 2;
1361                         count -= sizeof(*u);
1362                 }
1363         }
1364         return 0;
1365 }
1366
1367 static int s390_compat_regs_high_set(struct task_struct *target,
1368                                      const struct user_regset *regset,
1369                                      unsigned int pos, unsigned int count,
1370                                      const void *kbuf, const void __user *ubuf)
1371 {
1372         compat_ulong_t *gprs_high;
1373         int rc = 0;
1374
1375         gprs_high = (compat_ulong_t *)
1376                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1377         if (kbuf) {
1378                 const compat_ulong_t *k = kbuf;
1379                 while (count > 0) {
1380                         *gprs_high = *k++;
1381                         *gprs_high += 2;
1382                         count -= sizeof(*k);
1383                 }
1384         } else {
1385                 const compat_ulong_t  __user *u = ubuf;
1386                 while (count > 0 && !rc) {
1387                         unsigned long word;
1388                         rc = __get_user(word, u++);
1389                         if (rc)
1390                                 break;
1391                         *gprs_high = word;
1392                         *gprs_high += 2;
1393                         count -= sizeof(*u);
1394                 }
1395         }
1396
1397         return rc;
1398 }
1399
1400 static int s390_compat_last_break_get(struct task_struct *target,
1401                                       const struct user_regset *regset,
1402                                       unsigned int pos, unsigned int count,
1403                                       void *kbuf, void __user *ubuf)
1404 {
1405         compat_ulong_t last_break;
1406
1407         if (count > 0) {
1408                 last_break = task_thread_info(target)->last_break;
1409                 if (kbuf) {
1410                         unsigned long *k = kbuf;
1411                         *k = last_break;
1412                 } else {
1413                         unsigned long  __user *u = ubuf;
1414                         if (__put_user(last_break, u))
1415                                 return -EFAULT;
1416                 }
1417         }
1418         return 0;
1419 }
1420
1421 static int s390_compat_last_break_set(struct task_struct *target,
1422                                       const struct user_regset *regset,
1423                                       unsigned int pos, unsigned int count,
1424                                       const void *kbuf, const void __user *ubuf)
1425 {
1426         return 0;
1427 }
1428
1429 static const struct user_regset s390_compat_regsets[] = {
1430         {
1431                 .core_note_type = NT_PRSTATUS,
1432                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1433                 .size = sizeof(compat_long_t),
1434                 .align = sizeof(compat_long_t),
1435                 .get = s390_compat_regs_get,
1436                 .set = s390_compat_regs_set,
1437         },
1438         {
1439                 .core_note_type = NT_PRFPREG,
1440                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1441                 .size = sizeof(compat_long_t),
1442                 .align = sizeof(compat_long_t),
1443                 .get = s390_fpregs_get,
1444                 .set = s390_fpregs_set,
1445         },
1446         {
1447                 .core_note_type = NT_S390_SYSTEM_CALL,
1448                 .n = 1,
1449                 .size = sizeof(compat_uint_t),
1450                 .align = sizeof(compat_uint_t),
1451                 .get = s390_system_call_get,
1452                 .set = s390_system_call_set,
1453         },
1454         {
1455                 .core_note_type = NT_S390_LAST_BREAK,
1456                 .n = 1,
1457                 .size = sizeof(long),
1458                 .align = sizeof(long),
1459                 .get = s390_compat_last_break_get,
1460                 .set = s390_compat_last_break_set,
1461         },
1462         {
1463                 .core_note_type = NT_S390_TDB,
1464                 .n = 1,
1465                 .size = 256,
1466                 .align = 1,
1467                 .get = s390_tdb_get,
1468                 .set = s390_tdb_set,
1469         },
1470         {
1471                 .core_note_type = NT_S390_VXRS_LOW,
1472                 .n = __NUM_VXRS_LOW,
1473                 .size = sizeof(__u64),
1474                 .align = sizeof(__u64),
1475                 .get = s390_vxrs_low_get,
1476                 .set = s390_vxrs_low_set,
1477         },
1478         {
1479                 .core_note_type = NT_S390_VXRS_HIGH,
1480                 .n = __NUM_VXRS_HIGH,
1481                 .size = sizeof(__vector128),
1482                 .align = sizeof(__vector128),
1483                 .get = s390_vxrs_high_get,
1484                 .set = s390_vxrs_high_set,
1485         },
1486         {
1487                 .core_note_type = NT_S390_HIGH_GPRS,
1488                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1489                 .size = sizeof(compat_long_t),
1490                 .align = sizeof(compat_long_t),
1491                 .get = s390_compat_regs_high_get,
1492                 .set = s390_compat_regs_high_set,
1493         },
1494 };
1495
1496 static const struct user_regset_view user_s390_compat_view = {
1497         .name = "s390",
1498         .e_machine = EM_S390,
1499         .regsets = s390_compat_regsets,
1500         .n = ARRAY_SIZE(s390_compat_regsets)
1501 };
1502 #endif
1503
1504 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1505 {
1506 #ifdef CONFIG_COMPAT
1507         if (test_tsk_thread_flag(task, TIF_31BIT))
1508                 return &user_s390_compat_view;
1509 #endif
1510         return &user_s390_view;
1511 }
1512
1513 static const char *gpr_names[NUM_GPRS] = {
1514         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1515         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1516 };
1517
1518 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1519 {
1520         if (offset >= NUM_GPRS)
1521                 return 0;
1522         return regs->gprs[offset];
1523 }
1524
1525 int regs_query_register_offset(const char *name)
1526 {
1527         unsigned long offset;
1528
1529         if (!name || *name != 'r')
1530                 return -EINVAL;
1531         if (kstrtoul(name + 1, 10, &offset))
1532                 return -EINVAL;
1533         if (offset >= NUM_GPRS)
1534                 return -EINVAL;
1535         return offset;
1536 }
1537
1538 const char *regs_query_register_name(unsigned int offset)
1539 {
1540         if (offset >= NUM_GPRS)
1541                 return NULL;
1542         return gpr_names[offset];
1543 }
1544
1545 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1546 {
1547         unsigned long ksp = kernel_stack_pointer(regs);
1548
1549         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1550 }
1551
1552 /**
1553  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1554  * @regs:pt_regs which contains kernel stack pointer.
1555  * @n:stack entry number.
1556  *
1557  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1558  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1559  * this returns 0.
1560  */
1561 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1562 {
1563         unsigned long addr;
1564
1565         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1566         if (!regs_within_kernel_stack(regs, addr))
1567                 return 0;
1568         return *(unsigned long *)addr;
1569 }