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/sched/task_stack.h>
  12 #include <linux/mm.h>
  13 #include <linux/smp.h>
  14 #include <linux/errno.h>
  15 #include <linux/ptrace.h>
  16 #include <linux/user.h>
  17 #include <linux/security.h>
  18 #include <linux/audit.h>
  19 #include <linux/signal.h>
  20 #include <linux/elf.h>
  21 #include <linux/regset.h>
  22 #include <linux/tracehook.h>
  23 #include <linux/seccomp.h>
  24 #include <linux/compat.h>
  25 #include <trace/syscall.h>
  26 #include <asm/segment.h>
  27 #include <asm/page.h>
  28 #include <asm/pgtable.h>
  29 #include <asm/pgalloc.h>
  30 #include <linux/uaccess.h>
  31 #include <asm/unistd.h>
  32 #include <asm/switch_to.h>
  33 #include "entry.h"
  34
  35 #ifdef CONFIG_COMPAT
  36 #include "compat_ptrace.h"
  37 #endif
  38
  39 #define CREATE_TRACE_POINTS
  40 #include <trace/events/syscalls.h>
  41
  42 void update_cr_regs(struct task_struct *task)
  43 {
  44         struct pt_regs *regs = task_pt_regs(task);
  45         struct thread_struct *thread = &task->thread;
  46         struct per_regs old, new;
  47
  48         /* Take care of the enable/disable of transactional execution. */
  49         if (MACHINE_HAS_TE) {
  50                 unsigned long cr, cr_new;
  51
  52                 __ctl_store(cr, 0, 0);
  53                 /* Set or clear transaction execution TXC bit 8. */
  54                 cr_new = cr | (1UL << 55);
  55                 if (task->thread.per_flags & PER_FLAG_NO_TE)
  56                         cr_new &= ~(1UL << 55);
  57                 if (cr_new != cr)
  58                         __ctl_load(cr_new, 0, 0);
  59                 /* Set or clear transaction execution TDC bits 62 and 63. */
  60                 __ctl_store(cr, 2, 2);
  61                 cr_new = cr & ~3UL;
  62                 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
  63                         if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
  64                                 cr_new |= 1UL;
  65                         else
  66                                 cr_new |= 2UL;
  67                 }
  68                 if (cr_new != cr)
  69                         __ctl_load(cr_new, 2, 2);
  70         }
  71         /* Copy user specified PER registers */
  72         new.control = thread->per_user.control;
  73         new.start = thread->per_user.start;
  74         new.end = thread->per_user.end;
  75
  76         /* merge TIF_SINGLE_STEP into user specified PER registers. */
  77         if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
  78             test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
  79                 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
  80                         new.control |= PER_EVENT_BRANCH;
  81                 else
  82                         new.control |= PER_EVENT_IFETCH;
  83                 new.control |= PER_CONTROL_SUSPENSION;
  84                 new.control |= PER_EVENT_TRANSACTION_END;
  85                 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
  86                         new.control |= PER_EVENT_IFETCH;
  87                 new.start = 0;
  88                 new.end = -1UL;
  89         }
  90
  91         /* Take care of the PER enablement bit in the PSW. */
  92         if (!(new.control & PER_EVENT_MASK)) {
  93                 regs->psw.mask &= ~PSW_MASK_PER;
  94                 return;
  95         }
  96         regs->psw.mask |= PSW_MASK_PER;
  97         __ctl_store(old, 9, 11);
  98         if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
  99                 __ctl_load(new, 9, 11);
 100 }
 101
 102 void user_enable_single_step(struct task_struct *task)
 103 {
 104         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 105         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 106 }
 107
 108 void user_disable_single_step(struct task_struct *task)
 109 {
 110         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 111         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 112 }
 113
 114 void user_enable_block_step(struct task_struct *task)
 115 {
 116         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 117         set_tsk_thread_flag(task, TIF_BLOCK_STEP);
 118 }
 119
 120 /*
 121  * Called by kernel/ptrace.c when detaching..
 122  *
 123  * Clear all debugging related fields.
 124  */
 125 void ptrace_disable(struct task_struct *task)
 126 {
 127         memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 128         memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 129         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 130         clear_pt_regs_flag(task_pt_regs(task), PIF_PER_TRAP);
 131         task->thread.per_flags = 0;
 132 }
 133
 134 #define __ADDR_MASK 7
 135
 136 static inline unsigned long __peek_user_per(struct task_struct *child,
 137                                             addr_t addr)
 138 {
 139         struct per_struct_kernel *dummy = NULL;
 140
 141         if (addr == (addr_t) &dummy->cr9)
 142                 /* Control bits of the active per set. */
 143                 return test_thread_flag(TIF_SINGLE_STEP) ?
 144                         PER_EVENT_IFETCH : child->thread.per_user.control;
 145         else if (addr == (addr_t) &dummy->cr10)
 146                 /* Start address of the active per set. */
 147                 return test_thread_flag(TIF_SINGLE_STEP) ?
 148                         0 : child->thread.per_user.start;
 149         else if (addr == (addr_t) &dummy->cr11)
 150                 /* End address of the active per set. */
 151                 return test_thread_flag(TIF_SINGLE_STEP) ?
 152                         -1UL : child->thread.per_user.end;
 153         else if (addr == (addr_t) &dummy->bits)
 154                 /* Single-step bit. */
 155                 return test_thread_flag(TIF_SINGLE_STEP) ?
 156                         (1UL << (BITS_PER_LONG - 1)) : 0;
 157         else if (addr == (addr_t) &dummy->starting_addr)
 158                 /* Start address of the user specified per set. */
 159                 return child->thread.per_user.start;
 160         else if (addr == (addr_t) &dummy->ending_addr)
 161                 /* End address of the user specified per set. */
 162                 return child->thread.per_user.end;
 163         else if (addr == (addr_t) &dummy->perc_atmid)
 164                 /* PER code, ATMID and AI of the last PER trap */
 165                 return (unsigned long)
 166                         child->thread.per_event.cause << (BITS_PER_LONG - 16);
 167         else if (addr == (addr_t) &dummy->address)
 168                 /* Address of the last PER trap */
 169                 return child->thread.per_event.address;
 170         else if (addr == (addr_t) &dummy->access_id)
 171                 /* Access id of the last PER trap */
 172                 return (unsigned long)
 173                         child->thread.per_event.paid << (BITS_PER_LONG - 8);
 174         return 0;
 175 }
 176
 177 /*
 178  * Read the word at offset addr from the user area of a process. The
 179  * trouble here is that the information is littered over different
 180  * locations. The process registers are found on the kernel stack,
 181  * the floating point stuff and the trace settings are stored in
 182  * the task structure. In addition the different structures in
 183  * struct user contain pad bytes that should be read as zeroes.
 184  * Lovely...
 185  */
 186 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 187 {
 188         struct user *dummy = NULL;
 189         addr_t offset, tmp;
 190
 191         if (addr < (addr_t) &dummy->regs.acrs) {
 192                 /*
 193                  * psw and gprs are stored on the stack
 194                  */
 195                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 196                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 197                         /* Return a clean psw mask. */
 198                         tmp &= PSW_MASK_USER | PSW_MASK_RI;
 199                         tmp |= PSW_USER_BITS;
 200                 }
 201
 202         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 203                 /*
 204                  * access registers are stored in the thread structure
 205                  */
 206                 offset = addr - (addr_t) &dummy->regs.acrs;
 207                 /*
 208                  * Very special case: old & broken 64 bit gdb reading
 209                  * from acrs[15]. Result is a 64 bit value. Read the
 210                  * 32 bit acrs[15] value and shift it by 32. Sick...
 211                  */
 212                 if (addr == (addr_t) &dummy->regs.acrs[15])
 213                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 214                 else
 215                         tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 216
 217         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 218                 /*
 219                  * orig_gpr2 is stored on the kernel stack
 220                  */
 221                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 222
 223         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 224                 /*
 225                  * prevent reads of padding hole between
 226                  * orig_gpr2 and fp_regs on s390.
 227                  */
 228                 tmp = 0;
 229
 230         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 231                 /*
 232                  * floating point control reg. is in the thread structure
 233                  */
 234                 tmp = child->thread.fpu.fpc;
 235                 tmp <<= BITS_PER_LONG - 32;
 236
 237         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 238                 /*
 239                  * floating point regs. are either in child->thread.fpu
 240                  * or the child->thread.fpu.vxrs array
 241                  */
 242                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 243                 if (MACHINE_HAS_VX)
 244                         tmp = *(addr_t *)
 245                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 246                 else
 247                         tmp = *(addr_t *)
 248                                ((addr_t) child->thread.fpu.fprs + offset);
 249
 250         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 251                 /*
 252                  * Handle access to the per_info structure.
 253                  */
 254                 addr -= (addr_t) &dummy->regs.per_info;
 255                 tmp = __peek_user_per(child, addr);
 256
 257         } else
 258                 tmp = 0;
 259
 260         return tmp;
 261 }
 262
 263 static int
 264 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 265 {
 266         addr_t tmp, mask;
 267
 268         /*
 269          * Stupid gdb peeks/pokes the access registers in 64 bit with
 270          * an alignment of 4. Programmers from hell...
 271          */
 272         mask = __ADDR_MASK;
 273         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 274             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 275                 mask = 3;
 276         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 277                 return -EIO;
 278
 279         tmp = __peek_user(child, addr);
 280         return put_user(tmp, (addr_t __user *) data);
 281 }
 282
 283 static inline void __poke_user_per(struct task_struct *child,
 284                                    addr_t addr, addr_t data)
 285 {
 286         struct per_struct_kernel *dummy = NULL;
 287
 288         /*
 289          * There are only three fields in the per_info struct that the
 290          * debugger user can write to.
 291          * 1) cr9: the debugger wants to set a new PER event mask
 292          * 2) starting_addr: the debugger wants to set a new starting
 293          *    address to use with the PER event mask.
 294          * 3) ending_addr: the debugger wants to set a new ending
 295          *    address to use with the PER event mask.
 296          * The user specified PER event mask and the start and end
 297          * addresses are used only if single stepping is not in effect.
 298          * Writes to any other field in per_info are ignored.
 299          */
 300         if (addr == (addr_t) &dummy->cr9)
 301                 /* PER event mask of the user specified per set. */
 302                 child->thread.per_user.control =
 303                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 304         else if (addr == (addr_t) &dummy->starting_addr)
 305                 /* Starting address of the user specified per set. */
 306                 child->thread.per_user.start = data;
 307         else if (addr == (addr_t) &dummy->ending_addr)
 308                 /* Ending address of the user specified per set. */
 309                 child->thread.per_user.end = data;
 310 }
 311
 312 /*
 313  * Write a word to the user area of a process at location addr. This
 314  * operation does have an additional problem compared to peek_user.
 315  * Stores to the program status word and on the floating point
 316  * control register needs to get checked for validity.
 317  */
 318 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 319 {
 320         struct user *dummy = NULL;
 321         addr_t offset;
 322
 323         if (addr < (addr_t) &dummy->regs.acrs) {
 324                 /*
 325                  * psw and gprs are stored on the stack
 326                  */
 327                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 328                         unsigned long mask = PSW_MASK_USER;
 329
 330                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 331                         if ((data ^ PSW_USER_BITS) & ~mask)
 332                                 /* Invalid psw mask. */
 333                                 return -EINVAL;
 334                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 335                                 /* Invalid address-space-control bits */
 336                                 return -EINVAL;
 337                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 338                                 /* Invalid addressing mode bits */
 339                                 return -EINVAL;
 340                 }
 341                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 342
 343         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 344                 /*
 345                  * access registers are stored in the thread structure
 346                  */
 347                 offset = addr - (addr_t) &dummy->regs.acrs;
 348                 /*
 349                  * Very special case: old & broken 64 bit gdb writing
 350                  * to acrs[15] with a 64 bit value. Ignore the lower
 351                  * half of the value and write the upper 32 bit to
 352                  * acrs[15]. Sick...
 353                  */
 354                 if (addr == (addr_t) &dummy->regs.acrs[15])
 355                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 356                 else
 357                         *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 358
 359         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 360                 /*
 361                  * orig_gpr2 is stored on the kernel stack
 362                  */
 363                 task_pt_regs(child)->orig_gpr2 = data;
 364
 365         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 366                 /*
 367                  * prevent writes of padding hole between
 368                  * orig_gpr2 and fp_regs on s390.
 369                  */
 370                 return 0;
 371
 372         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 373                 /*
 374                  * floating point control reg. is in the thread structure
 375                  */
 376                 if ((unsigned int) data != 0 ||
 377                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 378                         return -EINVAL;
 379                 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
 380
 381         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 382                 /*
 383                  * floating point regs. are either in child->thread.fpu
 384                  * or the child->thread.fpu.vxrs array
 385                  */
 386                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 387                 if (MACHINE_HAS_VX)
 388                         *(addr_t *)((addr_t)
 389                                 child->thread.fpu.vxrs + 2*offset) = data;
 390                 else
 391                         *(addr_t *)((addr_t)
 392                                 child->thread.fpu.fprs + offset) = data;
 393
 394         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 395                 /*
 396                  * Handle access to the per_info structure.
 397                  */
 398                 addr -= (addr_t) &dummy->regs.per_info;
 399                 __poke_user_per(child, addr, data);
 400
 401         }
 402
 403         return 0;
 404 }
 405
 406 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 407 {
 408         addr_t mask;
 409
 410         /*
 411          * Stupid gdb peeks/pokes the access registers in 64 bit with
 412          * an alignment of 4. Programmers from hell indeed...
 413          */
 414         mask = __ADDR_MASK;
 415         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 416             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 417                 mask = 3;
 418         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 419                 return -EIO;
 420
 421         return __poke_user(child, addr, data);
 422 }
 423
 424 long arch_ptrace(struct task_struct *child, long request,
 425                  unsigned long addr, unsigned long data)
 426 {
 427         ptrace_area parea;
 428         int copied, ret;
 429
 430         switch (request) {
 431         case PTRACE_PEEKUSR:
 432                 /* read the word at location addr in the USER area. */
 433                 return peek_user(child, addr, data);
 434
 435         case PTRACE_POKEUSR:
 436                 /* write the word at location addr in the USER area */
 437                 return poke_user(child, addr, data);
 438
 439         case PTRACE_PEEKUSR_AREA:
 440         case PTRACE_POKEUSR_AREA:
 441                 if (copy_from_user(&parea, (void __force __user *) addr,
 442                                                         sizeof(parea)))
 443                         return -EFAULT;
 444                 addr = parea.kernel_addr;
 445                 data = parea.process_addr;
 446                 copied = 0;
 447                 while (copied < parea.len) {
 448                         if (request == PTRACE_PEEKUSR_AREA)
 449                                 ret = peek_user(child, addr, data);
 450                         else {
 451                                 addr_t utmp;
 452                                 if (get_user(utmp,
 453                                              (addr_t __force __user *) data))
 454                                         return -EFAULT;
 455                                 ret = poke_user(child, addr, utmp);
 456                         }
 457                         if (ret)
 458                                 return ret;
 459                         addr += sizeof(unsigned long);
 460                         data += sizeof(unsigned long);
 461                         copied += sizeof(unsigned long);
 462                 }
 463                 return 0;
 464         case PTRACE_GET_LAST_BREAK:
 465                 put_user(child->thread.last_break,
 466                          (unsigned long __user *) data);
 467                 return 0;
 468         case PTRACE_ENABLE_TE:
 469                 if (!MACHINE_HAS_TE)
 470                         return -EIO;
 471                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 472                 return 0;
 473         case PTRACE_DISABLE_TE:
 474                 if (!MACHINE_HAS_TE)
 475                         return -EIO;
 476                 child->thread.per_flags |= PER_FLAG_NO_TE;
 477                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 478                 return 0;
 479         case PTRACE_TE_ABORT_RAND:
 480                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 481                         return -EIO;
 482                 switch (data) {
 483                 case 0UL:
 484                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 485                         break;
 486                 case 1UL:
 487                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 488                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 489                         break;
 490                 case 2UL:
 491                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 492                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 493                         break;
 494                 default:
 495                         return -EINVAL;
 496                 }
 497                 return 0;
 498         default:
 499                 return ptrace_request(child, request, addr, data);
 500         }
 501 }
 502
 503 #ifdef CONFIG_COMPAT
 504 /*
 505  * Now the fun part starts... a 31 bit program running in the
 506  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 507  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 508  * to handle, the difference to the 64 bit versions of the requests
 509  * is that the access is done in multiples of 4 byte instead of
 510  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 511  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 512  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 513  * is a 31 bit program too, the content of struct user can be
 514  * emulated. A 31 bit program peeking into the struct user of
 515  * a 64 bit program is a no-no.
 516  */
 517
 518 /*
 519  * Same as peek_user_per but for a 31 bit program.
 520  */
 521 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 522                                            addr_t addr)
 523 {
 524         struct compat_per_struct_kernel *dummy32 = NULL;
 525
 526         if (addr == (addr_t) &dummy32->cr9)
 527                 /* Control bits of the active per set. */
 528                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 529                         PER_EVENT_IFETCH : child->thread.per_user.control;
 530         else if (addr == (addr_t) &dummy32->cr10)
 531                 /* Start address of the active per set. */
 532                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 533                         0 : child->thread.per_user.start;
 534         else if (addr == (addr_t) &dummy32->cr11)
 535                 /* End address of the active per set. */
 536                 return test_thread_flag(TIF_SINGLE_STEP) ?
 537                         PSW32_ADDR_INSN : child->thread.per_user.end;
 538         else if (addr == (addr_t) &dummy32->bits)
 539                 /* Single-step bit. */
 540                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 541                         0x80000000 : 0;
 542         else if (addr == (addr_t) &dummy32->starting_addr)
 543                 /* Start address of the user specified per set. */
 544                 return (__u32) child->thread.per_user.start;
 545         else if (addr == (addr_t) &dummy32->ending_addr)
 546                 /* End address of the user specified per set. */
 547                 return (__u32) child->thread.per_user.end;
 548         else if (addr == (addr_t) &dummy32->perc_atmid)
 549                 /* PER code, ATMID and AI of the last PER trap */
 550                 return (__u32) child->thread.per_event.cause << 16;
 551         else if (addr == (addr_t) &dummy32->address)
 552                 /* Address of the last PER trap */
 553                 return (__u32) child->thread.per_event.address;
 554         else if (addr == (addr_t) &dummy32->access_id)
 555                 /* Access id of the last PER trap */
 556                 return (__u32) child->thread.per_event.paid << 24;
 557         return 0;
 558 }
 559
 560 /*
 561  * Same as peek_user but for a 31 bit program.
 562  */
 563 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 564 {
 565         struct compat_user *dummy32 = NULL;
 566         addr_t offset;
 567         __u32 tmp;
 568
 569         if (addr < (addr_t) &dummy32->regs.acrs) {
 570                 struct pt_regs *regs = task_pt_regs(child);
 571                 /*
 572                  * psw and gprs are stored on the stack
 573                  */
 574                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 575                         /* Fake a 31 bit psw mask. */
 576                         tmp = (__u32)(regs->psw.mask >> 32);
 577                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 578                         tmp |= PSW32_USER_BITS;
 579                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 580                         /* Fake a 31 bit psw address. */
 581                         tmp = (__u32) regs->psw.addr |
 582                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 583                 } else {
 584                         /* gpr 0-15 */
 585                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 586                 }
 587         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 588                 /*
 589                  * access registers are stored in the thread structure
 590                  */
 591                 offset = addr - (addr_t) &dummy32->regs.acrs;
 592                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 593
 594         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 595                 /*
 596                  * orig_gpr2 is stored on the kernel stack
 597                  */
 598                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 599
 600         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 601                 /*
 602                  * prevent reads of padding hole between
 603                  * orig_gpr2 and fp_regs on s390.
 604                  */
 605                 tmp = 0;
 606
 607         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 608                 /*
 609                  * floating point control reg. is in the thread structure
 610                  */
 611                 tmp = child->thread.fpu.fpc;
 612
 613         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 614                 /*
 615                  * floating point regs. are either in child->thread.fpu
 616                  * or the child->thread.fpu.vxrs array
 617                  */
 618                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 619                 if (MACHINE_HAS_VX)
 620                         tmp = *(__u32 *)
 621                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 622                 else
 623                         tmp = *(__u32 *)
 624                                ((addr_t) child->thread.fpu.fprs + offset);
 625
 626         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 627                 /*
 628                  * Handle access to the per_info structure.
 629                  */
 630                 addr -= (addr_t) &dummy32->regs.per_info;
 631                 tmp = __peek_user_per_compat(child, addr);
 632
 633         } else
 634                 tmp = 0;
 635
 636         return tmp;
 637 }
 638
 639 static int peek_user_compat(struct task_struct *child,
 640                             addr_t addr, addr_t data)
 641 {
 642         __u32 tmp;
 643
 644         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 645                 return -EIO;
 646
 647         tmp = __peek_user_compat(child, addr);
 648         return put_user(tmp, (__u32 __user *) data);
 649 }
 650
 651 /*
 652  * Same as poke_user_per but for a 31 bit program.
 653  */
 654 static inline void __poke_user_per_compat(struct task_struct *child,
 655                                           addr_t addr, __u32 data)
 656 {
 657         struct compat_per_struct_kernel *dummy32 = NULL;
 658
 659         if (addr == (addr_t) &dummy32->cr9)
 660                 /* PER event mask of the user specified per set. */
 661                 child->thread.per_user.control =
 662                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 663         else if (addr == (addr_t) &dummy32->starting_addr)
 664                 /* Starting address of the user specified per set. */
 665                 child->thread.per_user.start = data;
 666         else if (addr == (addr_t) &dummy32->ending_addr)
 667                 /* Ending address of the user specified per set. */
 668                 child->thread.per_user.end = data;
 669 }
 670
 671 /*
 672  * Same as poke_user but for a 31 bit program.
 673  */
 674 static int __poke_user_compat(struct task_struct *child,
 675                               addr_t addr, addr_t data)
 676 {
 677         struct compat_user *dummy32 = NULL;
 678         __u32 tmp = (__u32) data;
 679         addr_t offset;
 680
 681         if (addr < (addr_t) &dummy32->regs.acrs) {
 682                 struct pt_regs *regs = task_pt_regs(child);
 683                 /*
 684                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 685                  */
 686                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 687                         __u32 mask = PSW32_MASK_USER;
 688
 689                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 690                         /* Build a 64 bit psw mask from 31 bit mask. */
 691                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 692                                 /* Invalid psw mask. */
 693                                 return -EINVAL;
 694                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 695                                 /* Invalid address-space-control bits */
 696                                 return -EINVAL;
 697                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 698                                 (regs->psw.mask & PSW_MASK_BA) |
 699                                 (__u64)(tmp & mask) << 32;
 700                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 701                         /* Build a 64 bit psw address from 31 bit address. */
 702                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 703                         /* Transfer 31 bit amode bit to psw mask. */
 704                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 705                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 706                 } else {
 707                         /* gpr 0-15 */
 708                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 709                 }
 710         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 711                 /*
 712                  * access registers are stored in the thread structure
 713                  */
 714                 offset = addr - (addr_t) &dummy32->regs.acrs;
 715                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 716
 717         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 718                 /*
 719                  * orig_gpr2 is stored on the kernel stack
 720                  */
 721                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 722
 723         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 724                 /*
 725                  * prevent writess of padding hole between
 726                  * orig_gpr2 and fp_regs on s390.
 727                  */
 728                 return 0;
 729
 730         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 731                 /*
 732                  * floating point control reg. is in the thread structure
 733                  */
 734                 if (test_fp_ctl(tmp))
 735                         return -EINVAL;
 736                 child->thread.fpu.fpc = data;
 737
 738         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 739                 /*
 740                  * floating point regs. are either in child->thread.fpu
 741                  * or the child->thread.fpu.vxrs array
 742                  */
 743                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 744                 if (MACHINE_HAS_VX)
 745                         *(__u32 *)((addr_t)
 746                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 747                 else
 748                         *(__u32 *)((addr_t)
 749                                 child->thread.fpu.fprs + offset) = tmp;
 750
 751         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 752                 /*
 753                  * Handle access to the per_info structure.
 754                  */
 755                 addr -= (addr_t) &dummy32->regs.per_info;
 756                 __poke_user_per_compat(child, addr, data);
 757         }
 758
 759         return 0;
 760 }
 761
 762 static int poke_user_compat(struct task_struct *child,
 763                             addr_t addr, addr_t data)
 764 {
 765         if (!is_compat_task() || (addr & 3) ||
 766             addr > sizeof(struct compat_user) - 3)
 767                 return -EIO;
 768
 769         return __poke_user_compat(child, addr, data);
 770 }
 771
 772 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 773                         compat_ulong_t caddr, compat_ulong_t cdata)
 774 {
 775         unsigned long addr = caddr;
 776         unsigned long data = cdata;
 777         compat_ptrace_area parea;
 778         int copied, ret;
 779
 780         switch (request) {
 781         case PTRACE_PEEKUSR:
 782                 /* read the word at location addr in the USER area. */
 783                 return peek_user_compat(child, addr, data);
 784
 785         case PTRACE_POKEUSR:
 786                 /* write the word at location addr in the USER area */
 787                 return poke_user_compat(child, addr, data);
 788
 789         case PTRACE_PEEKUSR_AREA:
 790         case PTRACE_POKEUSR_AREA:
 791                 if (copy_from_user(&parea, (void __force __user *) addr,
 792                                                         sizeof(parea)))
 793                         return -EFAULT;
 794                 addr = parea.kernel_addr;
 795                 data = parea.process_addr;
 796                 copied = 0;
 797                 while (copied < parea.len) {
 798                         if (request == PTRACE_PEEKUSR_AREA)
 799                                 ret = peek_user_compat(child, addr, data);
 800                         else {
 801                                 __u32 utmp;
 802                                 if (get_user(utmp,
 803                                              (__u32 __force __user *) data))
 804                                         return -EFAULT;
 805                                 ret = poke_user_compat(child, addr, utmp);
 806                         }
 807                         if (ret)
 808                                 return ret;
 809                         addr += sizeof(unsigned int);
 810                         data += sizeof(unsigned int);
 811                         copied += sizeof(unsigned int);
 812                 }
 813                 return 0;
 814         case PTRACE_GET_LAST_BREAK:
 815                 put_user(child->thread.last_break,
 816                          (unsigned int __user *) data);
 817                 return 0;
 818         }
 819         return compat_ptrace_request(child, request, addr, data);
 820 }
 821 #endif
 822
 823 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 824 {
 825         unsigned long mask = -1UL;
 826
 827         /*
 828          * The sysc_tracesys code in entry.S stored the system
 829          * call number to gprs[2].
 830          */
 831         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 832             (tracehook_report_syscall_entry(regs) ||
 833              regs->gprs[2] >= NR_syscalls)) {
 834                 /*
 835                  * Tracing decided this syscall should not happen or the
 836                  * debugger stored an invalid system call number. Skip
 837                  * the system call and the system call restart handling.
 838                  */
 839                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 840                 return -1;
 841         }
 842
 843         /* Do the secure computing check after ptrace. */
 844         if (secure_computing(NULL)) {
 845                 /* seccomp failures shouldn't expose any additional code. */
 846                 return -1;
 847         }
 848
 849         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 850                 trace_sys_enter(regs, regs->gprs[2]);
 851
 852         if (is_compat_task())
 853                 mask = 0xffffffff;
 854
 855         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
 856                             regs->gprs[3] &mask, regs->gprs[4] &mask,
 857                             regs->gprs[5] &mask);
 858
 859         return regs->gprs[2];
 860 }
 861
 862 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 863 {
 864         audit_syscall_exit(regs);
 865
 866         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 867                 trace_sys_exit(regs, regs->gprs[2]);
 868
 869         if (test_thread_flag(TIF_SYSCALL_TRACE))
 870                 tracehook_report_syscall_exit(regs, 0);
 871 }
 872
 873 /*
 874  * user_regset definitions.
 875  */
 876
 877 static int s390_regs_get(struct task_struct *target,
 878                          const struct user_regset *regset,
 879                          unsigned int pos, unsigned int count,
 880                          void *kbuf, void __user *ubuf)
 881 {
 882         if (target == current)
 883                 save_access_regs(target->thread.acrs);
 884
 885         if (kbuf) {
 886                 unsigned long *k = kbuf;
 887                 while (count > 0) {
 888                         *k++ = __peek_user(target, pos);
 889                         count -= sizeof(*k);
 890                         pos += sizeof(*k);
 891                 }
 892         } else {
 893                 unsigned long __user *u = ubuf;
 894                 while (count > 0) {
 895                         if (__put_user(__peek_user(target, pos), u++))
 896                                 return -EFAULT;
 897                         count -= sizeof(*u);
 898                         pos += sizeof(*u);
 899                 }
 900         }
 901         return 0;
 902 }
 903
 904 static int s390_regs_set(struct task_struct *target,
 905                          const struct user_regset *regset,
 906                          unsigned int pos, unsigned int count,
 907                          const void *kbuf, const void __user *ubuf)
 908 {
 909         int rc = 0;
 910
 911         if (target == current)
 912                 save_access_regs(target->thread.acrs);
 913
 914         if (kbuf) {
 915                 const unsigned long *k = kbuf;
 916                 while (count > 0 && !rc) {
 917                         rc = __poke_user(target, pos, *k++);
 918                         count -= sizeof(*k);
 919                         pos += sizeof(*k);
 920                 }
 921         } else {
 922                 const unsigned long  __user *u = ubuf;
 923                 while (count > 0 && !rc) {
 924                         unsigned long word;
 925                         rc = __get_user(word, u++);
 926                         if (rc)
 927                                 break;
 928                         rc = __poke_user(target, pos, word);
 929                         count -= sizeof(*u);
 930                         pos += sizeof(*u);
 931                 }
 932         }
 933
 934         if (rc == 0 && target == current)
 935                 restore_access_regs(target->thread.acrs);
 936
 937         return rc;
 938 }
 939
 940 static int s390_fpregs_get(struct task_struct *target,
 941                            const struct user_regset *regset, unsigned int pos,
 942                            unsigned int count, void *kbuf, void __user *ubuf)
 943 {
 944         _s390_fp_regs fp_regs;
 945
 946         if (target == current)
 947                 save_fpu_regs();
 948
 949         fp_regs.fpc = target->thread.fpu.fpc;
 950         fpregs_store(&fp_regs, &target->thread.fpu);
 951
 952         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 953                                    &fp_regs, 0, -1);
 954 }
 955
 956 static int s390_fpregs_set(struct task_struct *target,
 957                            const struct user_regset *regset, unsigned int pos,
 958                            unsigned int count, const void *kbuf,
 959                            const void __user *ubuf)
 960 {
 961         int rc = 0;
 962         freg_t fprs[__NUM_FPRS];
 963
 964         if (target == current)
 965                 save_fpu_regs();
 966
 967         if (MACHINE_HAS_VX)
 968                 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
 969         else
 970                 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
 971
 972         /* If setting FPC, must validate it first. */
 973         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 974                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
 975                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
 976                                         0, offsetof(s390_fp_regs, fprs));
 977                 if (rc)
 978                         return rc;
 979                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
 980                         return -EINVAL;
 981                 target->thread.fpu.fpc = ufpc[0];
 982         }
 983
 984         if (rc == 0 && count > 0)
 985                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 986                                         fprs, offsetof(s390_fp_regs, fprs), -1);
 987         if (rc)
 988                 return rc;
 989
 990         if (MACHINE_HAS_VX)
 991                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
 992         else
 993                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
 994
 995         return rc;
 996 }
 997
 998 static int s390_last_break_get(struct task_struct *target,
 999                                const struct user_regset *regset,
1000                                unsigned int pos, unsigned int count,
1001                                void *kbuf, void __user *ubuf)
1002 {
1003         if (count > 0) {
1004                 if (kbuf) {
1005                         unsigned long *k = kbuf;
1006                         *k = target->thread.last_break;
1007                 } else {
1008                         unsigned long  __user *u = ubuf;
1009                         if (__put_user(target->thread.last_break, u))
1010                                 return -EFAULT;
1011                 }
1012         }
1013         return 0;
1014 }
1015
1016 static int s390_last_break_set(struct task_struct *target,
1017                                const struct user_regset *regset,
1018                                unsigned int pos, unsigned int count,
1019                                const void *kbuf, const void __user *ubuf)
1020 {
1021         return 0;
1022 }
1023
1024 static int s390_tdb_get(struct task_struct *target,
1025                         const struct user_regset *regset,
1026                         unsigned int pos, unsigned int count,
1027                         void *kbuf, void __user *ubuf)
1028 {
1029         struct pt_regs *regs = task_pt_regs(target);
1030         unsigned char *data;
1031
1032         if (!(regs->int_code & 0x200))
1033                 return -ENODATA;
1034         data = target->thread.trap_tdb;
1035         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1036 }
1037
1038 static int s390_tdb_set(struct task_struct *target,
1039                         const struct user_regset *regset,
1040                         unsigned int pos, unsigned int count,
1041                         const void *kbuf, const void __user *ubuf)
1042 {
1043         return 0;
1044 }
1045
1046 static int s390_vxrs_low_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         __u64 vxrs[__NUM_VXRS_LOW];
1052         int i;
1053
1054         if (!MACHINE_HAS_VX)
1055                 return -ENODEV;
1056         if (target == current)
1057                 save_fpu_regs();
1058         for (i = 0; i < __NUM_VXRS_LOW; i++)
1059                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1060         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1061 }
1062
1063 static int s390_vxrs_low_set(struct task_struct *target,
1064                              const struct user_regset *regset,
1065                              unsigned int pos, unsigned int count,
1066                              const void *kbuf, const void __user *ubuf)
1067 {
1068         __u64 vxrs[__NUM_VXRS_LOW];
1069         int i, rc;
1070
1071         if (!MACHINE_HAS_VX)
1072                 return -ENODEV;
1073         if (target == current)
1074                 save_fpu_regs();
1075
1076         for (i = 0; i < __NUM_VXRS_LOW; i++)
1077                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1078
1079         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1080         if (rc == 0)
1081                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1082                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1083
1084         return rc;
1085 }
1086
1087 static int s390_vxrs_high_get(struct task_struct *target,
1088                               const struct user_regset *regset,
1089                               unsigned int pos, unsigned int count,
1090                               void *kbuf, void __user *ubuf)
1091 {
1092         __vector128 vxrs[__NUM_VXRS_HIGH];
1093
1094         if (!MACHINE_HAS_VX)
1095                 return -ENODEV;
1096         if (target == current)
1097                 save_fpu_regs();
1098         memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1099
1100         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1101 }
1102
1103 static int s390_vxrs_high_set(struct task_struct *target,
1104                               const struct user_regset *regset,
1105                               unsigned int pos, unsigned int count,
1106                               const void *kbuf, const void __user *ubuf)
1107 {
1108         int rc;
1109
1110         if (!MACHINE_HAS_VX)
1111                 return -ENODEV;
1112         if (target == current)
1113                 save_fpu_regs();
1114
1115         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1116                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1117         return rc;
1118 }
1119
1120 static int s390_system_call_get(struct task_struct *target,
1121                                 const struct user_regset *regset,
1122                                 unsigned int pos, unsigned int count,
1123                                 void *kbuf, void __user *ubuf)
1124 {
1125         unsigned int *data = &target->thread.system_call;
1126         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1127                                    data, 0, sizeof(unsigned int));
1128 }
1129
1130 static int s390_system_call_set(struct task_struct *target,
1131                                 const struct user_regset *regset,
1132                                 unsigned int pos, unsigned int count,
1133                                 const void *kbuf, const void __user *ubuf)
1134 {
1135         unsigned int *data = &target->thread.system_call;
1136         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1137                                   data, 0, sizeof(unsigned int));
1138 }
1139
1140 static const struct user_regset s390_regsets[] = {
1141         {
1142                 .core_note_type = NT_PRSTATUS,
1143                 .n = sizeof(s390_regs) / sizeof(long),
1144                 .size = sizeof(long),
1145                 .align = sizeof(long),
1146                 .get = s390_regs_get,
1147                 .set = s390_regs_set,
1148         },
1149         {
1150                 .core_note_type = NT_PRFPREG,
1151                 .n = sizeof(s390_fp_regs) / sizeof(long),
1152                 .size = sizeof(long),
1153                 .align = sizeof(long),
1154                 .get = s390_fpregs_get,
1155                 .set = s390_fpregs_set,
1156         },
1157         {
1158                 .core_note_type = NT_S390_SYSTEM_CALL,
1159                 .n = 1,
1160                 .size = sizeof(unsigned int),
1161                 .align = sizeof(unsigned int),
1162                 .get = s390_system_call_get,
1163                 .set = s390_system_call_set,
1164         },
1165         {
1166                 .core_note_type = NT_S390_LAST_BREAK,
1167                 .n = 1,
1168                 .size = sizeof(long),
1169                 .align = sizeof(long),
1170                 .get = s390_last_break_get,
1171                 .set = s390_last_break_set,
1172         },
1173         {
1174                 .core_note_type = NT_S390_TDB,
1175                 .n = 1,
1176                 .size = 256,
1177                 .align = 1,
1178                 .get = s390_tdb_get,
1179                 .set = s390_tdb_set,
1180         },
1181         {
1182                 .core_note_type = NT_S390_VXRS_LOW,
1183                 .n = __NUM_VXRS_LOW,
1184                 .size = sizeof(__u64),
1185                 .align = sizeof(__u64),
1186                 .get = s390_vxrs_low_get,
1187                 .set = s390_vxrs_low_set,
1188         },
1189         {
1190                 .core_note_type = NT_S390_VXRS_HIGH,
1191                 .n = __NUM_VXRS_HIGH,
1192                 .size = sizeof(__vector128),
1193                 .align = sizeof(__vector128),
1194                 .get = s390_vxrs_high_get,
1195                 .set = s390_vxrs_high_set,
1196         },
1197 };
1198
1199 static const struct user_regset_view user_s390_view = {
1200         .name = UTS_MACHINE,
1201         .e_machine = EM_S390,
1202         .regsets = s390_regsets,
1203         .n = ARRAY_SIZE(s390_regsets)
1204 };
1205
1206 #ifdef CONFIG_COMPAT
1207 static int s390_compat_regs_get(struct task_struct *target,
1208                                 const struct user_regset *regset,
1209                                 unsigned int pos, unsigned int count,
1210                                 void *kbuf, void __user *ubuf)
1211 {
1212         if (target == current)
1213                 save_access_regs(target->thread.acrs);
1214
1215         if (kbuf) {
1216                 compat_ulong_t *k = kbuf;
1217                 while (count > 0) {
1218                         *k++ = __peek_user_compat(target, pos);
1219                         count -= sizeof(*k);
1220                         pos += sizeof(*k);
1221                 }
1222         } else {
1223                 compat_ulong_t __user *u = ubuf;
1224                 while (count > 0) {
1225                         if (__put_user(__peek_user_compat(target, pos), u++))
1226                                 return -EFAULT;
1227                         count -= sizeof(*u);
1228                         pos += sizeof(*u);
1229                 }
1230         }
1231         return 0;
1232 }
1233
1234 static int s390_compat_regs_set(struct task_struct *target,
1235                                 const struct user_regset *regset,
1236                                 unsigned int pos, unsigned int count,
1237                                 const void *kbuf, const void __user *ubuf)
1238 {
1239         int rc = 0;
1240
1241         if (target == current)
1242                 save_access_regs(target->thread.acrs);
1243
1244         if (kbuf) {
1245                 const compat_ulong_t *k = kbuf;
1246                 while (count > 0 && !rc) {
1247                         rc = __poke_user_compat(target, pos, *k++);
1248                         count -= sizeof(*k);
1249                         pos += sizeof(*k);
1250                 }
1251         } else {
1252                 const compat_ulong_t  __user *u = ubuf;
1253                 while (count > 0 && !rc) {
1254                         compat_ulong_t word;
1255                         rc = __get_user(word, u++);
1256                         if (rc)
1257                                 break;
1258                         rc = __poke_user_compat(target, pos, word);
1259                         count -= sizeof(*u);
1260                         pos += sizeof(*u);
1261                 }
1262         }
1263
1264         if (rc == 0 && target == current)
1265                 restore_access_regs(target->thread.acrs);
1266
1267         return rc;
1268 }
1269
1270 static int s390_compat_regs_high_get(struct task_struct *target,
1271                                      const struct user_regset *regset,
1272                                      unsigned int pos, unsigned int count,
1273                                      void *kbuf, void __user *ubuf)
1274 {
1275         compat_ulong_t *gprs_high;
1276
1277         gprs_high = (compat_ulong_t *)
1278                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1279         if (kbuf) {
1280                 compat_ulong_t *k = kbuf;
1281                 while (count > 0) {
1282                         *k++ = *gprs_high;
1283                         gprs_high += 2;
1284                         count -= sizeof(*k);
1285                 }
1286         } else {
1287                 compat_ulong_t __user *u = ubuf;
1288                 while (count > 0) {
1289                         if (__put_user(*gprs_high, u++))
1290                                 return -EFAULT;
1291                         gprs_high += 2;
1292                         count -= sizeof(*u);
1293                 }
1294         }
1295         return 0;
1296 }
1297
1298 static int s390_compat_regs_high_set(struct task_struct *target,
1299                                      const struct user_regset *regset,
1300                                      unsigned int pos, unsigned int count,
1301                                      const void *kbuf, const void __user *ubuf)
1302 {
1303         compat_ulong_t *gprs_high;
1304         int rc = 0;
1305
1306         gprs_high = (compat_ulong_t *)
1307                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1308         if (kbuf) {
1309                 const compat_ulong_t *k = kbuf;
1310                 while (count > 0) {
1311                         *gprs_high = *k++;
1312                         *gprs_high += 2;
1313                         count -= sizeof(*k);
1314                 }
1315         } else {
1316                 const compat_ulong_t  __user *u = ubuf;
1317                 while (count > 0 && !rc) {
1318                         unsigned long word;
1319                         rc = __get_user(word, u++);
1320                         if (rc)
1321                                 break;
1322                         *gprs_high = word;
1323                         *gprs_high += 2;
1324                         count -= sizeof(*u);
1325                 }
1326         }
1327
1328         return rc;
1329 }
1330
1331 static int s390_compat_last_break_get(struct task_struct *target,
1332                                       const struct user_regset *regset,
1333                                       unsigned int pos, unsigned int count,
1334                                       void *kbuf, void __user *ubuf)
1335 {
1336         compat_ulong_t last_break;
1337
1338         if (count > 0) {
1339                 last_break = target->thread.last_break;
1340                 if (kbuf) {
1341                         unsigned long *k = kbuf;
1342                         *k = last_break;
1343                 } else {
1344                         unsigned long  __user *u = ubuf;
1345                         if (__put_user(last_break, u))
1346                                 return -EFAULT;
1347                 }
1348         }
1349         return 0;
1350 }
1351
1352 static int s390_compat_last_break_set(struct task_struct *target,
1353                                       const struct user_regset *regset,
1354                                       unsigned int pos, unsigned int count,
1355                                       const void *kbuf, const void __user *ubuf)
1356 {
1357         return 0;
1358 }
1359
1360 static const struct user_regset s390_compat_regsets[] = {
1361         {
1362                 .core_note_type = NT_PRSTATUS,
1363                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1364                 .size = sizeof(compat_long_t),
1365                 .align = sizeof(compat_long_t),
1366                 .get = s390_compat_regs_get,
1367                 .set = s390_compat_regs_set,
1368         },
1369         {
1370                 .core_note_type = NT_PRFPREG,
1371                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1372                 .size = sizeof(compat_long_t),
1373                 .align = sizeof(compat_long_t),
1374                 .get = s390_fpregs_get,
1375                 .set = s390_fpregs_set,
1376         },
1377         {
1378                 .core_note_type = NT_S390_SYSTEM_CALL,
1379                 .n = 1,
1380                 .size = sizeof(compat_uint_t),
1381                 .align = sizeof(compat_uint_t),
1382                 .get = s390_system_call_get,
1383                 .set = s390_system_call_set,
1384         },
1385         {
1386                 .core_note_type = NT_S390_LAST_BREAK,
1387                 .n = 1,
1388                 .size = sizeof(long),
1389                 .align = sizeof(long),
1390                 .get = s390_compat_last_break_get,
1391                 .set = s390_compat_last_break_set,
1392         },
1393         {
1394                 .core_note_type = NT_S390_TDB,
1395                 .n = 1,
1396                 .size = 256,
1397                 .align = 1,
1398                 .get = s390_tdb_get,
1399                 .set = s390_tdb_set,
1400         },
1401         {
1402                 .core_note_type = NT_S390_VXRS_LOW,
1403                 .n = __NUM_VXRS_LOW,
1404                 .size = sizeof(__u64),
1405                 .align = sizeof(__u64),
1406                 .get = s390_vxrs_low_get,
1407                 .set = s390_vxrs_low_set,
1408         },
1409         {
1410                 .core_note_type = NT_S390_VXRS_HIGH,
1411                 .n = __NUM_VXRS_HIGH,
1412                 .size = sizeof(__vector128),
1413                 .align = sizeof(__vector128),
1414                 .get = s390_vxrs_high_get,
1415                 .set = s390_vxrs_high_set,
1416         },
1417         {
1418                 .core_note_type = NT_S390_HIGH_GPRS,
1419                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1420                 .size = sizeof(compat_long_t),
1421                 .align = sizeof(compat_long_t),
1422                 .get = s390_compat_regs_high_get,
1423                 .set = s390_compat_regs_high_set,
1424         },
1425 };
1426
1427 static const struct user_regset_view user_s390_compat_view = {
1428         .name = "s390",
1429         .e_machine = EM_S390,
1430         .regsets = s390_compat_regsets,
1431         .n = ARRAY_SIZE(s390_compat_regsets)
1432 };
1433 #endif
1434
1435 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1436 {
1437 #ifdef CONFIG_COMPAT
1438         if (test_tsk_thread_flag(task, TIF_31BIT))
1439                 return &user_s390_compat_view;
1440 #endif
1441         return &user_s390_view;
1442 }
1443
1444 static const char *gpr_names[NUM_GPRS] = {
1445         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1446         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1447 };
1448
1449 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1450 {
1451         if (offset >= NUM_GPRS)
1452                 return 0;
1453         return regs->gprs[offset];
1454 }
1455
1456 int regs_query_register_offset(const char *name)
1457 {
1458         unsigned long offset;
1459
1460         if (!name || *name != 'r')
1461                 return -EINVAL;
1462         if (kstrtoul(name + 1, 10, &offset))
1463                 return -EINVAL;
1464         if (offset >= NUM_GPRS)
1465                 return -EINVAL;
1466         return offset;
1467 }
1468
1469 const char *regs_query_register_name(unsigned int offset)
1470 {
1471         if (offset >= NUM_GPRS)
1472                 return NULL;
1473         return gpr_names[offset];
1474 }
1475
1476 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1477 {
1478         unsigned long ksp = kernel_stack_pointer(regs);
1479
1480         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1481 }
1482
1483 /**
1484  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1485  * @regs:pt_regs which contains kernel stack pointer.
1486  * @n:stack entry number.
1487  *
1488  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1489  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1490  * this returns 0.
1491  */
1492 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1493 {
1494         unsigned long addr;
1495
1496         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1497         if (!regs_within_kernel_stack(regs, addr))
1498                 return 0;
1499         return *(unsigned long *)addr;
1500 }