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         /* Take care of the enable/disable of transactional execution. */
  48         if (MACHINE_HAS_TE) {
  49                 unsigned long cr, cr_new;
  50
  51                 __ctl_store(cr, 0, 0);
  52                 /* Set or clear transaction execution TXC bit 8. */
  53                 cr_new = cr | (1UL << 55);
  54                 if (task->thread.per_flags & PER_FLAG_NO_TE)
  55                         cr_new &= ~(1UL << 55);
  56                 if (cr_new != cr)
  57                         __ctl_load(cr_new, 0, 0);
  58                 /* Set or clear transaction execution TDC bits 62 and 63. */
  59                 __ctl_store(cr, 2, 2);
  60                 cr_new = cr & ~3UL;
  61                 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
  62                         if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
  63                                 cr_new |= 1UL;
  64                         else
  65                                 cr_new |= 2UL;
  66                 }
  67                 if (cr_new != cr)
  68                         __ctl_load(cr_new, 2, 2);
  69         }
  70         /* Copy user specified PER registers */
  71         new.control = thread->per_user.control;
  72         new.start = thread->per_user.start;
  73         new.end = thread->per_user.end;
  74
  75         /* merge TIF_SINGLE_STEP into user specified PER registers. */
  76         if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
  77             test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
  78                 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
  79                         new.control |= PER_EVENT_BRANCH;
  80                 else
  81                         new.control |= PER_EVENT_IFETCH;
  82                 new.control |= PER_CONTROL_SUSPENSION;
  83                 new.control |= PER_EVENT_TRANSACTION_END;
  84                 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
  85                         new.control |= PER_EVENT_IFETCH;
  86                 new.start = 0;
  87                 new.end = -1UL;
  88         }
  89
  90         /* Take care of the PER enablement bit in the PSW. */
  91         if (!(new.control & PER_EVENT_MASK)) {
  92                 regs->psw.mask &= ~PSW_MASK_PER;
  93                 return;
  94         }
  95         regs->psw.mask |= PSW_MASK_PER;
  96         __ctl_store(old, 9, 11);
  97         if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
  98                 __ctl_load(new, 9, 11);
  99 }
 100
 101 void user_enable_single_step(struct task_struct *task)
 102 {
 103         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 104         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 105 }
 106
 107 void user_disable_single_step(struct task_struct *task)
 108 {
 109         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 110         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 111 }
 112
 113 void user_enable_block_step(struct task_struct *task)
 114 {
 115         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 116         set_tsk_thread_flag(task, TIF_BLOCK_STEP);
 117 }
 118
 119 /*
 120  * Called by kernel/ptrace.c when detaching..
 121  *
 122  * Clear all debugging related fields.
 123  */
 124 void ptrace_disable(struct task_struct *task)
 125 {
 126         memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 127         memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 128         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 129         clear_pt_regs_flag(task_pt_regs(task), PIF_PER_TRAP);
 130         task->thread.per_flags = 0;
 131 }
 132
 133 #define __ADDR_MASK 7
 134
 135 static inline unsigned long __peek_user_per(struct task_struct *child,
 136                                             addr_t addr)
 137 {
 138         struct per_struct_kernel *dummy = NULL;
 139
 140         if (addr == (addr_t) &dummy->cr9)
 141                 /* Control bits of the active per set. */
 142                 return test_thread_flag(TIF_SINGLE_STEP) ?
 143                         PER_EVENT_IFETCH : child->thread.per_user.control;
 144         else if (addr == (addr_t) &dummy->cr10)
 145                 /* Start address of the active per set. */
 146                 return test_thread_flag(TIF_SINGLE_STEP) ?
 147                         0 : child->thread.per_user.start;
 148         else if (addr == (addr_t) &dummy->cr11)
 149                 /* End address of the active per set. */
 150                 return test_thread_flag(TIF_SINGLE_STEP) ?
 151                         -1UL : child->thread.per_user.end;
 152         else if (addr == (addr_t) &dummy->bits)
 153                 /* Single-step bit. */
 154                 return test_thread_flag(TIF_SINGLE_STEP) ?
 155                         (1UL << (BITS_PER_LONG - 1)) : 0;
 156         else if (addr == (addr_t) &dummy->starting_addr)
 157                 /* Start address of the user specified per set. */
 158                 return child->thread.per_user.start;
 159         else if (addr == (addr_t) &dummy->ending_addr)
 160                 /* End address of the user specified per set. */
 161                 return child->thread.per_user.end;
 162         else if (addr == (addr_t) &dummy->perc_atmid)
 163                 /* PER code, ATMID and AI of the last PER trap */
 164                 return (unsigned long)
 165                         child->thread.per_event.cause << (BITS_PER_LONG - 16);
 166         else if (addr == (addr_t) &dummy->address)
 167                 /* Address of the last PER trap */
 168                 return child->thread.per_event.address;
 169         else if (addr == (addr_t) &dummy->access_id)
 170                 /* Access id of the last PER trap */
 171                 return (unsigned long)
 172                         child->thread.per_event.paid << (BITS_PER_LONG - 8);
 173         return 0;
 174 }
 175
 176 /*
 177  * Read the word at offset addr from the user area of a process. The
 178  * trouble here is that the information is littered over different
 179  * locations. The process registers are found on the kernel stack,
 180  * the floating point stuff and the trace settings are stored in
 181  * the task structure. In addition the different structures in
 182  * struct user contain pad bytes that should be read as zeroes.
 183  * Lovely...
 184  */
 185 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 186 {
 187         struct user *dummy = NULL;
 188         addr_t offset, tmp;
 189
 190         if (addr < (addr_t) &dummy->regs.acrs) {
 191                 /*
 192                  * psw and gprs are stored on the stack
 193                  */
 194                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 195                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 196                         /* Return a clean psw mask. */
 197                         tmp &= PSW_MASK_USER | PSW_MASK_RI;
 198                         tmp |= PSW_USER_BITS;
 199                 }
 200
 201         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 202                 /*
 203                  * access registers are stored in the thread structure
 204                  */
 205                 offset = addr - (addr_t) &dummy->regs.acrs;
 206                 /*
 207                  * Very special case: old & broken 64 bit gdb reading
 208                  * from acrs[15]. Result is a 64 bit value. Read the
 209                  * 32 bit acrs[15] value and shift it by 32. Sick...
 210                  */
 211                 if (addr == (addr_t) &dummy->regs.acrs[15])
 212                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 213                 else
 214                         tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 215
 216         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 217                 /*
 218                  * orig_gpr2 is stored on the kernel stack
 219                  */
 220                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 221
 222         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 223                 /*
 224                  * prevent reads of padding hole between
 225                  * orig_gpr2 and fp_regs on s390.
 226                  */
 227                 tmp = 0;
 228
 229         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 230                 /*
 231                  * floating point control reg. is in the thread structure
 232                  */
 233                 tmp = child->thread.fpu.fpc;
 234                 tmp <<= BITS_PER_LONG - 32;
 235
 236         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 237                 /*
 238                  * floating point regs. are either in child->thread.fpu
 239                  * or the child->thread.fpu.vxrs array
 240                  */
 241                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 242                 if (MACHINE_HAS_VX)
 243                         tmp = *(addr_t *)
 244                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 245                 else
 246                         tmp = *(addr_t *)
 247                                ((addr_t) child->thread.fpu.fprs + offset);
 248
 249         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 250                 /*
 251                  * Handle access to the per_info structure.
 252                  */
 253                 addr -= (addr_t) &dummy->regs.per_info;
 254                 tmp = __peek_user_per(child, addr);
 255
 256         } else
 257                 tmp = 0;
 258
 259         return tmp;
 260 }
 261
 262 static int
 263 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 264 {
 265         addr_t tmp, mask;
 266
 267         /*
 268          * Stupid gdb peeks/pokes the access registers in 64 bit with
 269          * an alignment of 4. Programmers from hell...
 270          */
 271         mask = __ADDR_MASK;
 272         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 273             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 274                 mask = 3;
 275         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 276                 return -EIO;
 277
 278         tmp = __peek_user(child, addr);
 279         return put_user(tmp, (addr_t __user *) data);
 280 }
 281
 282 static inline void __poke_user_per(struct task_struct *child,
 283                                    addr_t addr, addr_t data)
 284 {
 285         struct per_struct_kernel *dummy = NULL;
 286
 287         /*
 288          * There are only three fields in the per_info struct that the
 289          * debugger user can write to.
 290          * 1) cr9: the debugger wants to set a new PER event mask
 291          * 2) starting_addr: the debugger wants to set a new starting
 292          *    address to use with the PER event mask.
 293          * 3) ending_addr: the debugger wants to set a new ending
 294          *    address to use with the PER event mask.
 295          * The user specified PER event mask and the start and end
 296          * addresses are used only if single stepping is not in effect.
 297          * Writes to any other field in per_info are ignored.
 298          */
 299         if (addr == (addr_t) &dummy->cr9)
 300                 /* PER event mask of the user specified per set. */
 301                 child->thread.per_user.control =
 302                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 303         else if (addr == (addr_t) &dummy->starting_addr)
 304                 /* Starting address of the user specified per set. */
 305                 child->thread.per_user.start = data;
 306         else if (addr == (addr_t) &dummy->ending_addr)
 307                 /* Ending address of the user specified per set. */
 308                 child->thread.per_user.end = data;
 309 }
 310
 311 /*
 312  * Write a word to the user area of a process at location addr. This
 313  * operation does have an additional problem compared to peek_user.
 314  * Stores to the program status word and on the floating point
 315  * control register needs to get checked for validity.
 316  */
 317 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 318 {
 319         struct user *dummy = NULL;
 320         addr_t offset;
 321
 322         if (addr < (addr_t) &dummy->regs.acrs) {
 323                 /*
 324                  * psw and gprs are stored on the stack
 325                  */
 326                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 327                         unsigned long mask = PSW_MASK_USER;
 328
 329                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 330                         if ((data ^ PSW_USER_BITS) & ~mask)
 331                                 /* Invalid psw mask. */
 332                                 return -EINVAL;
 333                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 334                                 /* Invalid address-space-control bits */
 335                                 return -EINVAL;
 336                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 337                                 /* Invalid addressing mode bits */
 338                                 return -EINVAL;
 339                 }
 340                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 341
 342         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 343                 /*
 344                  * access registers are stored in the thread structure
 345                  */
 346                 offset = addr - (addr_t) &dummy->regs.acrs;
 347                 /*
 348                  * Very special case: old & broken 64 bit gdb writing
 349                  * to acrs[15] with a 64 bit value. Ignore the lower
 350                  * half of the value and write the upper 32 bit to
 351                  * acrs[15]. Sick...
 352                  */
 353                 if (addr == (addr_t) &dummy->regs.acrs[15])
 354                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 355                 else
 356                         *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 357
 358         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 359                 /*
 360                  * orig_gpr2 is stored on the kernel stack
 361                  */
 362                 task_pt_regs(child)->orig_gpr2 = data;
 363
 364         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 365                 /*
 366                  * prevent writes of padding hole between
 367                  * orig_gpr2 and fp_regs on s390.
 368                  */
 369                 return 0;
 370
 371         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 372                 /*
 373                  * floating point control reg. is in the thread structure
 374                  */
 375                 if ((unsigned int) data != 0 ||
 376                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 377                         return -EINVAL;
 378                 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
 379
 380         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 381                 /*
 382                  * floating point regs. are either in child->thread.fpu
 383                  * or the child->thread.fpu.vxrs array
 384                  */
 385                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 386                 if (MACHINE_HAS_VX)
 387                         *(addr_t *)((addr_t)
 388                                 child->thread.fpu.vxrs + 2*offset) = data;
 389                 else
 390                         *(addr_t *)((addr_t)
 391                                 child->thread.fpu.fprs + offset) = data;
 392
 393         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 394                 /*
 395                  * Handle access to the per_info structure.
 396                  */
 397                 addr -= (addr_t) &dummy->regs.per_info;
 398                 __poke_user_per(child, addr, data);
 399
 400         }
 401
 402         return 0;
 403 }
 404
 405 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 406 {
 407         addr_t mask;
 408
 409         /*
 410          * Stupid gdb peeks/pokes the access registers in 64 bit with
 411          * an alignment of 4. Programmers from hell indeed...
 412          */
 413         mask = __ADDR_MASK;
 414         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 415             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 416                 mask = 3;
 417         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 418                 return -EIO;
 419
 420         return __poke_user(child, addr, data);
 421 }
 422
 423 long arch_ptrace(struct task_struct *child, long request,
 424                  unsigned long addr, unsigned long data)
 425 {
 426         ptrace_area parea;
 427         int copied, ret;
 428
 429         switch (request) {
 430         case PTRACE_PEEKUSR:
 431                 /* read the word at location addr in the USER area. */
 432                 return peek_user(child, addr, data);
 433
 434         case PTRACE_POKEUSR:
 435                 /* write the word at location addr in the USER area */
 436                 return poke_user(child, addr, data);
 437
 438         case PTRACE_PEEKUSR_AREA:
 439         case PTRACE_POKEUSR_AREA:
 440                 if (copy_from_user(&parea, (void __force __user *) addr,
 441                                                         sizeof(parea)))
 442                         return -EFAULT;
 443                 addr = parea.kernel_addr;
 444                 data = parea.process_addr;
 445                 copied = 0;
 446                 while (copied < parea.len) {
 447                         if (request == PTRACE_PEEKUSR_AREA)
 448                                 ret = peek_user(child, addr, data);
 449                         else {
 450                                 addr_t utmp;
 451                                 if (get_user(utmp,
 452                                              (addr_t __force __user *) data))
 453                                         return -EFAULT;
 454                                 ret = poke_user(child, addr, utmp);
 455                         }
 456                         if (ret)
 457                                 return ret;
 458                         addr += sizeof(unsigned long);
 459                         data += sizeof(unsigned long);
 460                         copied += sizeof(unsigned long);
 461                 }
 462                 return 0;
 463         case PTRACE_GET_LAST_BREAK:
 464                 put_user(task_thread_info(child)->last_break,
 465                          (unsigned long __user *) data);
 466                 return 0;
 467         case PTRACE_ENABLE_TE:
 468                 if (!MACHINE_HAS_TE)
 469                         return -EIO;
 470                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 471                 return 0;
 472         case PTRACE_DISABLE_TE:
 473                 if (!MACHINE_HAS_TE)
 474                         return -EIO;
 475                 child->thread.per_flags |= PER_FLAG_NO_TE;
 476                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 477                 return 0;
 478         case PTRACE_TE_ABORT_RAND:
 479                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 480                         return -EIO;
 481                 switch (data) {
 482                 case 0UL:
 483                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 484                         break;
 485                 case 1UL:
 486                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 487                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 488                         break;
 489                 case 2UL:
 490                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 491                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 492                         break;
 493                 default:
 494                         return -EINVAL;
 495                 }
 496                 return 0;
 497         default:
 498                 return ptrace_request(child, request, addr, data);
 499         }
 500 }
 501
 502 #ifdef CONFIG_COMPAT
 503 /*
 504  * Now the fun part starts... a 31 bit program running in the
 505  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 506  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 507  * to handle, the difference to the 64 bit versions of the requests
 508  * is that the access is done in multiples of 4 byte instead of
 509  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 510  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 511  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 512  * is a 31 bit program too, the content of struct user can be
 513  * emulated. A 31 bit program peeking into the struct user of
 514  * a 64 bit program is a no-no.
 515  */
 516
 517 /*
 518  * Same as peek_user_per but for a 31 bit program.
 519  */
 520 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 521                                            addr_t addr)
 522 {
 523         struct compat_per_struct_kernel *dummy32 = NULL;
 524
 525         if (addr == (addr_t) &dummy32->cr9)
 526                 /* Control bits of the active per set. */
 527                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 528                         PER_EVENT_IFETCH : child->thread.per_user.control;
 529         else if (addr == (addr_t) &dummy32->cr10)
 530                 /* Start address of the active per set. */
 531                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 532                         0 : child->thread.per_user.start;
 533         else if (addr == (addr_t) &dummy32->cr11)
 534                 /* End address of the active per set. */
 535                 return test_thread_flag(TIF_SINGLE_STEP) ?
 536                         PSW32_ADDR_INSN : child->thread.per_user.end;
 537         else if (addr == (addr_t) &dummy32->bits)
 538                 /* Single-step bit. */
 539                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 540                         0x80000000 : 0;
 541         else if (addr == (addr_t) &dummy32->starting_addr)
 542                 /* Start address of the user specified per set. */
 543                 return (__u32) child->thread.per_user.start;
 544         else if (addr == (addr_t) &dummy32->ending_addr)
 545                 /* End address of the user specified per set. */
 546                 return (__u32) child->thread.per_user.end;
 547         else if (addr == (addr_t) &dummy32->perc_atmid)
 548                 /* PER code, ATMID and AI of the last PER trap */
 549                 return (__u32) child->thread.per_event.cause << 16;
 550         else if (addr == (addr_t) &dummy32->address)
 551                 /* Address of the last PER trap */
 552                 return (__u32) child->thread.per_event.address;
 553         else if (addr == (addr_t) &dummy32->access_id)
 554                 /* Access id of the last PER trap */
 555                 return (__u32) child->thread.per_event.paid << 24;
 556         return 0;
 557 }
 558
 559 /*
 560  * Same as peek_user but for a 31 bit program.
 561  */
 562 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 563 {
 564         struct compat_user *dummy32 = NULL;
 565         addr_t offset;
 566         __u32 tmp;
 567
 568         if (addr < (addr_t) &dummy32->regs.acrs) {
 569                 struct pt_regs *regs = task_pt_regs(child);
 570                 /*
 571                  * psw and gprs are stored on the stack
 572                  */
 573                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 574                         /* Fake a 31 bit psw mask. */
 575                         tmp = (__u32)(regs->psw.mask >> 32);
 576                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 577                         tmp |= PSW32_USER_BITS;
 578                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 579                         /* Fake a 31 bit psw address. */
 580                         tmp = (__u32) regs->psw.addr |
 581                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 582                 } else {
 583                         /* gpr 0-15 */
 584                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 585                 }
 586         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 587                 /*
 588                  * access registers are stored in the thread structure
 589                  */
 590                 offset = addr - (addr_t) &dummy32->regs.acrs;
 591                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 592
 593         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 594                 /*
 595                  * orig_gpr2 is stored on the kernel stack
 596                  */
 597                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 598
 599         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 600                 /*
 601                  * prevent reads of padding hole between
 602                  * orig_gpr2 and fp_regs on s390.
 603                  */
 604                 tmp = 0;
 605
 606         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 607                 /*
 608                  * floating point control reg. is in the thread structure
 609                  */
 610                 tmp = child->thread.fpu.fpc;
 611
 612         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 613                 /*
 614                  * floating point regs. are either in child->thread.fpu
 615                  * or the child->thread.fpu.vxrs array
 616                  */
 617                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 618                 if (MACHINE_HAS_VX)
 619                         tmp = *(__u32 *)
 620                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 621                 else
 622                         tmp = *(__u32 *)
 623                                ((addr_t) child->thread.fpu.fprs + offset);
 624
 625         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 626                 /*
 627                  * Handle access to the per_info structure.
 628                  */
 629                 addr -= (addr_t) &dummy32->regs.per_info;
 630                 tmp = __peek_user_per_compat(child, addr);
 631
 632         } else
 633                 tmp = 0;
 634
 635         return tmp;
 636 }
 637
 638 static int peek_user_compat(struct task_struct *child,
 639                             addr_t addr, addr_t data)
 640 {
 641         __u32 tmp;
 642
 643         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 644                 return -EIO;
 645
 646         tmp = __peek_user_compat(child, addr);
 647         return put_user(tmp, (__u32 __user *) data);
 648 }
 649
 650 /*
 651  * Same as poke_user_per but for a 31 bit program.
 652  */
 653 static inline void __poke_user_per_compat(struct task_struct *child,
 654                                           addr_t addr, __u32 data)
 655 {
 656         struct compat_per_struct_kernel *dummy32 = NULL;
 657
 658         if (addr == (addr_t) &dummy32->cr9)
 659                 /* PER event mask of the user specified per set. */
 660                 child->thread.per_user.control =
 661                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 662         else if (addr == (addr_t) &dummy32->starting_addr)
 663                 /* Starting address of the user specified per set. */
 664                 child->thread.per_user.start = data;
 665         else if (addr == (addr_t) &dummy32->ending_addr)
 666                 /* Ending address of the user specified per set. */
 667                 child->thread.per_user.end = data;
 668 }
 669
 670 /*
 671  * Same as poke_user but for a 31 bit program.
 672  */
 673 static int __poke_user_compat(struct task_struct *child,
 674                               addr_t addr, addr_t data)
 675 {
 676         struct compat_user *dummy32 = NULL;
 677         __u32 tmp = (__u32) data;
 678         addr_t offset;
 679
 680         if (addr < (addr_t) &dummy32->regs.acrs) {
 681                 struct pt_regs *regs = task_pt_regs(child);
 682                 /*
 683                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 684                  */
 685                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 686                         __u32 mask = PSW32_MASK_USER;
 687
 688                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 689                         /* Build a 64 bit psw mask from 31 bit mask. */
 690                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 691                                 /* Invalid psw mask. */
 692                                 return -EINVAL;
 693                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 694                                 /* Invalid address-space-control bits */
 695                                 return -EINVAL;
 696                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 697                                 (regs->psw.mask & PSW_MASK_BA) |
 698                                 (__u64)(tmp & mask) << 32;
 699                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 700                         /* Build a 64 bit psw address from 31 bit address. */
 701                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 702                         /* Transfer 31 bit amode bit to psw mask. */
 703                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 704                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 705                 } else {
 706                         /* gpr 0-15 */
 707                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 708                 }
 709         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 710                 /*
 711                  * access registers are stored in the thread structure
 712                  */
 713                 offset = addr - (addr_t) &dummy32->regs.acrs;
 714                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 715
 716         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 717                 /*
 718                  * orig_gpr2 is stored on the kernel stack
 719                  */
 720                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 721
 722         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 723                 /*
 724                  * prevent writess of padding hole between
 725                  * orig_gpr2 and fp_regs on s390.
 726                  */
 727                 return 0;
 728
 729         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 730                 /*
 731                  * floating point control reg. is in the thread structure
 732                  */
 733                 if (test_fp_ctl(tmp))
 734                         return -EINVAL;
 735                 child->thread.fpu.fpc = data;
 736
 737         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 738                 /*
 739                  * floating point regs. are either in child->thread.fpu
 740                  * or the child->thread.fpu.vxrs array
 741                  */
 742                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 743                 if (MACHINE_HAS_VX)
 744                         *(__u32 *)((addr_t)
 745                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 746                 else
 747                         *(__u32 *)((addr_t)
 748                                 child->thread.fpu.fprs + offset) = tmp;
 749
 750         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 751                 /*
 752                  * Handle access to the per_info structure.
 753                  */
 754                 addr -= (addr_t) &dummy32->regs.per_info;
 755                 __poke_user_per_compat(child, addr, data);
 756         }
 757
 758         return 0;
 759 }
 760
 761 static int poke_user_compat(struct task_struct *child,
 762                             addr_t addr, addr_t data)
 763 {
 764         if (!is_compat_task() || (addr & 3) ||
 765             addr > sizeof(struct compat_user) - 3)
 766                 return -EIO;
 767
 768         return __poke_user_compat(child, addr, data);
 769 }
 770
 771 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 772                         compat_ulong_t caddr, compat_ulong_t cdata)
 773 {
 774         unsigned long addr = caddr;
 775         unsigned long data = cdata;
 776         compat_ptrace_area parea;
 777         int copied, ret;
 778
 779         switch (request) {
 780         case PTRACE_PEEKUSR:
 781                 /* read the word at location addr in the USER area. */
 782                 return peek_user_compat(child, addr, data);
 783
 784         case PTRACE_POKEUSR:
 785                 /* write the word at location addr in the USER area */
 786                 return poke_user_compat(child, addr, data);
 787
 788         case PTRACE_PEEKUSR_AREA:
 789         case PTRACE_POKEUSR_AREA:
 790                 if (copy_from_user(&parea, (void __force __user *) addr,
 791                                                         sizeof(parea)))
 792                         return -EFAULT;
 793                 addr = parea.kernel_addr;
 794                 data = parea.process_addr;
 795                 copied = 0;
 796                 while (copied < parea.len) {
 797                         if (request == PTRACE_PEEKUSR_AREA)
 798                                 ret = peek_user_compat(child, addr, data);
 799                         else {
 800                                 __u32 utmp;
 801                                 if (get_user(utmp,
 802                                              (__u32 __force __user *) data))
 803                                         return -EFAULT;
 804                                 ret = poke_user_compat(child, addr, utmp);
 805                         }
 806                         if (ret)
 807                                 return ret;
 808                         addr += sizeof(unsigned int);
 809                         data += sizeof(unsigned int);
 810                         copied += sizeof(unsigned int);
 811                 }
 812                 return 0;
 813         case PTRACE_GET_LAST_BREAK:
 814                 put_user(task_thread_info(child)->last_break,
 815                          (unsigned int __user *) data);
 816                 return 0;
 817         }
 818         return compat_ptrace_request(child, request, addr, data);
 819 }
 820 #endif
 821
 822 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 823 {
 824         long ret = 0;
 825         unsigned long mask = -1UL;
 826
 827         /* Do the secure computing check first. */
 828         if (secure_computing()) {
 829                 /* seccomp failures shouldn't expose any additional code. */
 830                 ret = -1;
 831                 goto out;
 832         }
 833
 834         /*
 835          * The sysc_tracesys code in entry.S stored the system
 836          * call number to gprs[2].
 837          */
 838         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 839             (tracehook_report_syscall_entry(regs) ||
 840              regs->gprs[2] >= NR_syscalls)) {
 841                 /*
 842                  * Tracing decided this syscall should not happen or the
 843                  * debugger stored an invalid system call number. Skip
 844                  * the system call and the system call restart handling.
 845                  */
 846                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 847                 ret = -1;
 848         }
 849
 850         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 851                 trace_sys_enter(regs, regs->gprs[2]);
 852
 853         if (is_compat_task())
 854                 mask = 0xffffffff;
 855
 856         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
 857                             regs->gprs[3] & mask, regs->gprs[4] & mask,
 858                             regs->gprs[5] & mask);
 859 out:
 860         return ret ?: regs->gprs[2];
 861 }
 862
 863 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 864 {
 865         audit_syscall_exit(regs);
 866
 867         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 868                 trace_sys_exit(regs, regs->gprs[2]);
 869
 870         if (test_thread_flag(TIF_SYSCALL_TRACE))
 871                 tracehook_report_syscall_exit(regs, 0);
 872 }
 873
 874 /*
 875  * user_regset definitions.
 876  */
 877
 878 static int s390_regs_get(struct task_struct *target,
 879                          const struct user_regset *regset,
 880                          unsigned int pos, unsigned int count,
 881                          void *kbuf, void __user *ubuf)
 882 {
 883         if (target == current)
 884                 save_access_regs(target->thread.acrs);
 885
 886         if (kbuf) {
 887                 unsigned long *k = kbuf;
 888                 while (count > 0) {
 889                         *k++ = __peek_user(target, pos);
 890                         count -= sizeof(*k);
 891                         pos += sizeof(*k);
 892                 }
 893         } else {
 894                 unsigned long __user *u = ubuf;
 895                 while (count > 0) {
 896                         if (__put_user(__peek_user(target, pos), u++))
 897                                 return -EFAULT;
 898                         count -= sizeof(*u);
 899                         pos += sizeof(*u);
 900                 }
 901         }
 902         return 0;
 903 }
 904
 905 static int s390_regs_set(struct task_struct *target,
 906                          const struct user_regset *regset,
 907                          unsigned int pos, unsigned int count,
 908                          const void *kbuf, const void __user *ubuf)
 909 {
 910         int rc = 0;
 911
 912         if (target == current)
 913                 save_access_regs(target->thread.acrs);
 914
 915         if (kbuf) {
 916                 const unsigned long *k = kbuf;
 917                 while (count > 0 && !rc) {
 918                         rc = __poke_user(target, pos, *k++);
 919                         count -= sizeof(*k);
 920                         pos += sizeof(*k);
 921                 }
 922         } else {
 923                 const unsigned long  __user *u = ubuf;
 924                 while (count > 0 && !rc) {
 925                         unsigned long word;
 926                         rc = __get_user(word, u++);
 927                         if (rc)
 928                                 break;
 929                         rc = __poke_user(target, pos, word);
 930                         count -= sizeof(*u);
 931                         pos += sizeof(*u);
 932                 }
 933         }
 934
 935         if (rc == 0 && target == current)
 936                 restore_access_regs(target->thread.acrs);
 937
 938         return rc;
 939 }
 940
 941 static int s390_fpregs_get(struct task_struct *target,
 942                            const struct user_regset *regset, unsigned int pos,
 943                            unsigned int count, void *kbuf, void __user *ubuf)
 944 {
 945         _s390_fp_regs fp_regs;
 946
 947         if (target == current)
 948                 save_fpu_regs();
 949
 950         fp_regs.fpc = target->thread.fpu.fpc;
 951         fpregs_store(&fp_regs, &target->thread.fpu);
 952
 953         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 954                                    &fp_regs, 0, -1);
 955 }
 956
 957 static int s390_fpregs_set(struct task_struct *target,
 958                            const struct user_regset *regset, unsigned int pos,
 959                            unsigned int count, const void *kbuf,
 960                            const void __user *ubuf)
 961 {
 962         int rc = 0;
 963         freg_t fprs[__NUM_FPRS];
 964
 965         if (target == current)
 966                 save_fpu_regs();
 967
 968         /* If setting FPC, must validate it first. */
 969         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 970                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
 971                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
 972                                         0, offsetof(s390_fp_regs, fprs));
 973                 if (rc)
 974                         return rc;
 975                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
 976                         return -EINVAL;
 977                 target->thread.fpu.fpc = ufpc[0];
 978         }
 979
 980         if (rc == 0 && count > 0)
 981                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 982                                         fprs, offsetof(s390_fp_regs, fprs), -1);
 983         if (rc)
 984                 return rc;
 985
 986         if (MACHINE_HAS_VX)
 987                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
 988         else
 989                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
 990
 991         return rc;
 992 }
 993
 994 static int s390_last_break_get(struct task_struct *target,
 995                                const struct user_regset *regset,
 996                                unsigned int pos, unsigned int count,
 997                                void *kbuf, void __user *ubuf)
 998 {
 999         if (count > 0) {
1000                 if (kbuf) {
1001                         unsigned long *k = kbuf;
1002                         *k = task_thread_info(target)->last_break;
1003                 } else {
1004                         unsigned long  __user *u = ubuf;
1005                         if (__put_user(task_thread_info(target)->last_break, u))
1006                                 return -EFAULT;
1007                 }
1008         }
1009         return 0;
1010 }
1011
1012 static int s390_last_break_set(struct task_struct *target,
1013                                const struct user_regset *regset,
1014                                unsigned int pos, unsigned int count,
1015                                const void *kbuf, const void __user *ubuf)
1016 {
1017         return 0;
1018 }
1019
1020 static int s390_tdb_get(struct task_struct *target,
1021                         const struct user_regset *regset,
1022                         unsigned int pos, unsigned int count,
1023                         void *kbuf, void __user *ubuf)
1024 {
1025         struct pt_regs *regs = task_pt_regs(target);
1026         unsigned char *data;
1027
1028         if (!(regs->int_code & 0x200))
1029                 return -ENODATA;
1030         data = target->thread.trap_tdb;
1031         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1032 }
1033
1034 static int s390_tdb_set(struct task_struct *target,
1035                         const struct user_regset *regset,
1036                         unsigned int pos, unsigned int count,
1037                         const void *kbuf, const void __user *ubuf)
1038 {
1039         return 0;
1040 }
1041
1042 static int s390_vxrs_low_get(struct task_struct *target,
1043                              const struct user_regset *regset,
1044                              unsigned int pos, unsigned int count,
1045                              void *kbuf, void __user *ubuf)
1046 {
1047         __u64 vxrs[__NUM_VXRS_LOW];
1048         int i;
1049
1050         if (!MACHINE_HAS_VX)
1051                 return -ENODEV;
1052         if (target == current)
1053                 save_fpu_regs();
1054         for (i = 0; i < __NUM_VXRS_LOW; i++)
1055                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1056         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1057 }
1058
1059 static int s390_vxrs_low_set(struct task_struct *target,
1060                              const struct user_regset *regset,
1061                              unsigned int pos, unsigned int count,
1062                              const void *kbuf, const void __user *ubuf)
1063 {
1064         __u64 vxrs[__NUM_VXRS_LOW];
1065         int i, rc;
1066
1067         if (!MACHINE_HAS_VX)
1068                 return -ENODEV;
1069         if (target == current)
1070                 save_fpu_regs();
1071
1072         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1073         if (rc == 0)
1074                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1075                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1076
1077         return rc;
1078 }
1079
1080 static int s390_vxrs_high_get(struct task_struct *target,
1081                               const struct user_regset *regset,
1082                               unsigned int pos, unsigned int count,
1083                               void *kbuf, void __user *ubuf)
1084 {
1085         __vector128 vxrs[__NUM_VXRS_HIGH];
1086
1087         if (!MACHINE_HAS_VX)
1088                 return -ENODEV;
1089         if (target == current)
1090                 save_fpu_regs();
1091         memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1092
1093         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1094 }
1095
1096 static int s390_vxrs_high_set(struct task_struct *target,
1097                               const struct user_regset *regset,
1098                               unsigned int pos, unsigned int count,
1099                               const void *kbuf, const void __user *ubuf)
1100 {
1101         int rc;
1102
1103         if (!MACHINE_HAS_VX)
1104                 return -ENODEV;
1105         if (target == current)
1106                 save_fpu_regs();
1107
1108         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1109                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1110         return rc;
1111 }
1112
1113 static int s390_system_call_get(struct task_struct *target,
1114                                 const struct user_regset *regset,
1115                                 unsigned int pos, unsigned int count,
1116                                 void *kbuf, void __user *ubuf)
1117 {
1118         unsigned int *data = &task_thread_info(target)->system_call;
1119         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1120                                    data, 0, sizeof(unsigned int));
1121 }
1122
1123 static int s390_system_call_set(struct task_struct *target,
1124                                 const struct user_regset *regset,
1125                                 unsigned int pos, unsigned int count,
1126                                 const void *kbuf, const void __user *ubuf)
1127 {
1128         unsigned int *data = &task_thread_info(target)->system_call;
1129         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1130                                   data, 0, sizeof(unsigned int));
1131 }
1132
1133 static const struct user_regset s390_regsets[] = {
1134         {
1135                 .core_note_type = NT_PRSTATUS,
1136                 .n = sizeof(s390_regs) / sizeof(long),
1137                 .size = sizeof(long),
1138                 .align = sizeof(long),
1139                 .get = s390_regs_get,
1140                 .set = s390_regs_set,
1141         },
1142         {
1143                 .core_note_type = NT_PRFPREG,
1144                 .n = sizeof(s390_fp_regs) / sizeof(long),
1145                 .size = sizeof(long),
1146                 .align = sizeof(long),
1147                 .get = s390_fpregs_get,
1148                 .set = s390_fpregs_set,
1149         },
1150         {
1151                 .core_note_type = NT_S390_SYSTEM_CALL,
1152                 .n = 1,
1153                 .size = sizeof(unsigned int),
1154                 .align = sizeof(unsigned int),
1155                 .get = s390_system_call_get,
1156                 .set = s390_system_call_set,
1157         },
1158         {
1159                 .core_note_type = NT_S390_LAST_BREAK,
1160                 .n = 1,
1161                 .size = sizeof(long),
1162                 .align = sizeof(long),
1163                 .get = s390_last_break_get,
1164                 .set = s390_last_break_set,
1165         },
1166         {
1167                 .core_note_type = NT_S390_TDB,
1168                 .n = 1,
1169                 .size = 256,
1170                 .align = 1,
1171                 .get = s390_tdb_get,
1172                 .set = s390_tdb_set,
1173         },
1174         {
1175                 .core_note_type = NT_S390_VXRS_LOW,
1176                 .n = __NUM_VXRS_LOW,
1177                 .size = sizeof(__u64),
1178                 .align = sizeof(__u64),
1179                 .get = s390_vxrs_low_get,
1180                 .set = s390_vxrs_low_set,
1181         },
1182         {
1183                 .core_note_type = NT_S390_VXRS_HIGH,
1184                 .n = __NUM_VXRS_HIGH,
1185                 .size = sizeof(__vector128),
1186                 .align = sizeof(__vector128),
1187                 .get = s390_vxrs_high_get,
1188                 .set = s390_vxrs_high_set,
1189         },
1190 };
1191
1192 static const struct user_regset_view user_s390_view = {
1193         .name = UTS_MACHINE,
1194         .e_machine = EM_S390,
1195         .regsets = s390_regsets,
1196         .n = ARRAY_SIZE(s390_regsets)
1197 };
1198
1199 #ifdef CONFIG_COMPAT
1200 static int s390_compat_regs_get(struct task_struct *target,
1201                                 const struct user_regset *regset,
1202                                 unsigned int pos, unsigned int count,
1203                                 void *kbuf, void __user *ubuf)
1204 {
1205         if (target == current)
1206                 save_access_regs(target->thread.acrs);
1207
1208         if (kbuf) {
1209                 compat_ulong_t *k = kbuf;
1210                 while (count > 0) {
1211                         *k++ = __peek_user_compat(target, pos);
1212                         count -= sizeof(*k);
1213                         pos += sizeof(*k);
1214                 }
1215         } else {
1216                 compat_ulong_t __user *u = ubuf;
1217                 while (count > 0) {
1218                         if (__put_user(__peek_user_compat(target, pos), u++))
1219                                 return -EFAULT;
1220                         count -= sizeof(*u);
1221                         pos += sizeof(*u);
1222                 }
1223         }
1224         return 0;
1225 }
1226
1227 static int s390_compat_regs_set(struct task_struct *target,
1228                                 const struct user_regset *regset,
1229                                 unsigned int pos, unsigned int count,
1230                                 const void *kbuf, const void __user *ubuf)
1231 {
1232         int rc = 0;
1233
1234         if (target == current)
1235                 save_access_regs(target->thread.acrs);
1236
1237         if (kbuf) {
1238                 const compat_ulong_t *k = kbuf;
1239                 while (count > 0 && !rc) {
1240                         rc = __poke_user_compat(target, pos, *k++);
1241                         count -= sizeof(*k);
1242                         pos += sizeof(*k);
1243                 }
1244         } else {
1245                 const compat_ulong_t  __user *u = ubuf;
1246                 while (count > 0 && !rc) {
1247                         compat_ulong_t word;
1248                         rc = __get_user(word, u++);
1249                         if (rc)
1250                                 break;
1251                         rc = __poke_user_compat(target, pos, word);
1252                         count -= sizeof(*u);
1253                         pos += sizeof(*u);
1254                 }
1255         }
1256
1257         if (rc == 0 && target == current)
1258                 restore_access_regs(target->thread.acrs);
1259
1260         return rc;
1261 }
1262
1263 static int s390_compat_regs_high_get(struct task_struct *target,
1264                                      const struct user_regset *regset,
1265                                      unsigned int pos, unsigned int count,
1266                                      void *kbuf, void __user *ubuf)
1267 {
1268         compat_ulong_t *gprs_high;
1269
1270         gprs_high = (compat_ulong_t *)
1271                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1272         if (kbuf) {
1273                 compat_ulong_t *k = kbuf;
1274                 while (count > 0) {
1275                         *k++ = *gprs_high;
1276                         gprs_high += 2;
1277                         count -= sizeof(*k);
1278                 }
1279         } else {
1280                 compat_ulong_t __user *u = ubuf;
1281                 while (count > 0) {
1282                         if (__put_user(*gprs_high, u++))
1283                                 return -EFAULT;
1284                         gprs_high += 2;
1285                         count -= sizeof(*u);
1286                 }
1287         }
1288         return 0;
1289 }
1290
1291 static int s390_compat_regs_high_set(struct task_struct *target,
1292                                      const struct user_regset *regset,
1293                                      unsigned int pos, unsigned int count,
1294                                      const void *kbuf, const void __user *ubuf)
1295 {
1296         compat_ulong_t *gprs_high;
1297         int rc = 0;
1298
1299         gprs_high = (compat_ulong_t *)
1300                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1301         if (kbuf) {
1302                 const compat_ulong_t *k = kbuf;
1303                 while (count > 0) {
1304                         *gprs_high = *k++;
1305                         *gprs_high += 2;
1306                         count -= sizeof(*k);
1307                 }
1308         } else {
1309                 const compat_ulong_t  __user *u = ubuf;
1310                 while (count > 0 && !rc) {
1311                         unsigned long word;
1312                         rc = __get_user(word, u++);
1313                         if (rc)
1314                                 break;
1315                         *gprs_high = word;
1316                         *gprs_high += 2;
1317                         count -= sizeof(*u);
1318                 }
1319         }
1320
1321         return rc;
1322 }
1323
1324 static int s390_compat_last_break_get(struct task_struct *target,
1325                                       const struct user_regset *regset,
1326                                       unsigned int pos, unsigned int count,
1327                                       void *kbuf, void __user *ubuf)
1328 {
1329         compat_ulong_t last_break;
1330
1331         if (count > 0) {
1332                 last_break = task_thread_info(target)->last_break;
1333                 if (kbuf) {
1334                         unsigned long *k = kbuf;
1335                         *k = last_break;
1336                 } else {
1337                         unsigned long  __user *u = ubuf;
1338                         if (__put_user(last_break, u))
1339                                 return -EFAULT;
1340                 }
1341         }
1342         return 0;
1343 }
1344
1345 static int s390_compat_last_break_set(struct task_struct *target,
1346                                       const struct user_regset *regset,
1347                                       unsigned int pos, unsigned int count,
1348                                       const void *kbuf, const void __user *ubuf)
1349 {
1350         return 0;
1351 }
1352
1353 static const struct user_regset s390_compat_regsets[] = {
1354         {
1355                 .core_note_type = NT_PRSTATUS,
1356                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1357                 .size = sizeof(compat_long_t),
1358                 .align = sizeof(compat_long_t),
1359                 .get = s390_compat_regs_get,
1360                 .set = s390_compat_regs_set,
1361         },
1362         {
1363                 .core_note_type = NT_PRFPREG,
1364                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1365                 .size = sizeof(compat_long_t),
1366                 .align = sizeof(compat_long_t),
1367                 .get = s390_fpregs_get,
1368                 .set = s390_fpregs_set,
1369         },
1370         {
1371                 .core_note_type = NT_S390_SYSTEM_CALL,
1372                 .n = 1,
1373                 .size = sizeof(compat_uint_t),
1374                 .align = sizeof(compat_uint_t),
1375                 .get = s390_system_call_get,
1376                 .set = s390_system_call_set,
1377         },
1378         {
1379                 .core_note_type = NT_S390_LAST_BREAK,
1380                 .n = 1,
1381                 .size = sizeof(long),
1382                 .align = sizeof(long),
1383                 .get = s390_compat_last_break_get,
1384                 .set = s390_compat_last_break_set,
1385         },
1386         {
1387                 .core_note_type = NT_S390_TDB,
1388                 .n = 1,
1389                 .size = 256,
1390                 .align = 1,
1391                 .get = s390_tdb_get,
1392                 .set = s390_tdb_set,
1393         },
1394         {
1395                 .core_note_type = NT_S390_VXRS_LOW,
1396                 .n = __NUM_VXRS_LOW,
1397                 .size = sizeof(__u64),
1398                 .align = sizeof(__u64),
1399                 .get = s390_vxrs_low_get,
1400                 .set = s390_vxrs_low_set,
1401         },
1402         {
1403                 .core_note_type = NT_S390_VXRS_HIGH,
1404                 .n = __NUM_VXRS_HIGH,
1405                 .size = sizeof(__vector128),
1406                 .align = sizeof(__vector128),
1407                 .get = s390_vxrs_high_get,
1408                 .set = s390_vxrs_high_set,
1409         },
1410         {
1411                 .core_note_type = NT_S390_HIGH_GPRS,
1412                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1413                 .size = sizeof(compat_long_t),
1414                 .align = sizeof(compat_long_t),
1415                 .get = s390_compat_regs_high_get,
1416                 .set = s390_compat_regs_high_set,
1417         },
1418 };
1419
1420 static const struct user_regset_view user_s390_compat_view = {
1421         .name = "s390",
1422         .e_machine = EM_S390,
1423         .regsets = s390_compat_regsets,
1424         .n = ARRAY_SIZE(s390_compat_regsets)
1425 };
1426 #endif
1427
1428 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1429 {
1430 #ifdef CONFIG_COMPAT
1431         if (test_tsk_thread_flag(task, TIF_31BIT))
1432                 return &user_s390_compat_view;
1433 #endif
1434         return &user_s390_view;
1435 }
1436
1437 static const char *gpr_names[NUM_GPRS] = {
1438         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1439         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1440 };
1441
1442 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1443 {
1444         if (offset >= NUM_GPRS)
1445                 return 0;
1446         return regs->gprs[offset];
1447 }
1448
1449 int regs_query_register_offset(const char *name)
1450 {
1451         unsigned long offset;
1452
1453         if (!name || *name != 'r')
1454                 return -EINVAL;
1455         if (kstrtoul(name + 1, 10, &offset))
1456                 return -EINVAL;
1457         if (offset >= NUM_GPRS)
1458                 return -EINVAL;
1459         return offset;
1460 }
1461
1462 const char *regs_query_register_name(unsigned int offset)
1463 {
1464         if (offset >= NUM_GPRS)
1465                 return NULL;
1466         return gpr_names[offset];
1467 }
1468
1469 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1470 {
1471         unsigned long ksp = kernel_stack_pointer(regs);
1472
1473         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1474 }
1475
1476 /**
1477  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1478  * @regs:pt_regs which contains kernel stack pointer.
1479  * @n:stack entry number.
1480  *
1481  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1482  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1483  * this returns 0.
1484  */
1485 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1486 {
1487         unsigned long addr;
1488
1489         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1490         if (!regs_within_kernel_stack(regs, addr))
1491                 return 0;
1492         return *(unsigned long *)addr;
1493 }