arch/s390/kernel/ptrace.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Ptrace user space interface.
   4  *
   5  *    Copyright IBM Corp. 1999, 2010
   6  *    Author(s): Denis Joseph Barrow
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/sched.h>
  12 #include <linux/sched/task_stack.h>
  13 #include <linux/mm.h>
  14 #include <linux/smp.h>
  15 #include <linux/errno.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/user.h>
  18 #include <linux/security.h>
  19 #include <linux/audit.h>
  20 #include <linux/signal.h>
  21 #include <linux/elf.h>
  22 #include <linux/regset.h>
  23 #include <linux/tracehook.h>
  24 #include <linux/seccomp.h>
  25 #include <linux/compat.h>
  26 #include <trace/syscall.h>
  27 #include <asm/segment.h>
  28 #include <asm/page.h>
  29 #include <asm/pgtable.h>
  30 #include <asm/pgalloc.h>
  31 #include <linux/uaccess.h>
  32 #include <asm/unistd.h>
  33 #include <asm/switch_to.h>
  34 #include <asm/runtime_instr.h>
  35 #include <asm/facility.h>
  36
  37 #include "entry.h"
  38
  39 #ifdef CONFIG_COMPAT
  40 #include "compat_ptrace.h"
  41 #endif
  42
  43 #define CREATE_TRACE_POINTS
  44 #include <trace/events/syscalls.h>
  45
  46 void update_cr_regs(struct task_struct *task)
  47 {
  48         struct pt_regs *regs = task_pt_regs(task);
  49         struct thread_struct *thread = &task->thread;
  50         struct per_regs old, new;
  51         union ctlreg0 cr0_old, cr0_new;
  52         union ctlreg2 cr2_old, cr2_new;
  53         int cr0_changed, cr2_changed;
  54
  55         __ctl_store(cr0_old.val, 0, 0);
  56         __ctl_store(cr2_old.val, 2, 2);
  57         cr0_new = cr0_old;
  58         cr2_new = cr2_old;
  59         /* Take care of the enable/disable of transactional execution. */
  60         if (MACHINE_HAS_TE) {
  61                 /* Set or clear transaction execution TXC bit 8. */
  62                 cr0_new.tcx = 1;
  63                 if (task->thread.per_flags & PER_FLAG_NO_TE)
  64                         cr0_new.tcx = 0;
  65                 /* Set or clear transaction execution TDC bits 62 and 63. */
  66                 cr2_new.tdc = 0;
  67                 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
  68                         if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
  69                                 cr2_new.tdc = 1;
  70                         else
  71                                 cr2_new.tdc = 2;
  72                 }
  73         }
  74         /* Take care of enable/disable of guarded storage. */
  75         if (MACHINE_HAS_GS) {
  76                 cr2_new.gse = 0;
  77                 if (task->thread.gs_cb)
  78                         cr2_new.gse = 1;
  79         }
  80         /* Load control register 0/2 iff changed */
  81         cr0_changed = cr0_new.val != cr0_old.val;
  82         cr2_changed = cr2_new.val != cr2_old.val;
  83         if (cr0_changed)
  84                 __ctl_load(cr0_new.val, 0, 0);
  85         if (cr2_changed)
  86                 __ctl_load(cr2_new.val, 2, 2);
  87         /* Copy user specified PER registers */
  88         new.control = thread->per_user.control;
  89         new.start = thread->per_user.start;
  90         new.end = thread->per_user.end;
  91
  92         /* merge TIF_SINGLE_STEP into user specified PER registers. */
  93         if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
  94             test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
  95                 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
  96                         new.control |= PER_EVENT_BRANCH;
  97                 else
  98                         new.control |= PER_EVENT_IFETCH;
  99                 new.control |= PER_CONTROL_SUSPENSION;
 100                 new.control |= PER_EVENT_TRANSACTION_END;
 101                 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
 102                         new.control |= PER_EVENT_IFETCH;
 103                 new.start = 0;
 104                 new.end = -1UL;
 105         }
 106
 107         /* Take care of the PER enablement bit in the PSW. */
 108         if (!(new.control & PER_EVENT_MASK)) {
 109                 regs->psw.mask &= ~PSW_MASK_PER;
 110                 return;
 111         }
 112         regs->psw.mask |= PSW_MASK_PER;
 113         __ctl_store(old, 9, 11);
 114         if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
 115                 __ctl_load(new, 9, 11);
 116 }
 117
 118 void user_enable_single_step(struct task_struct *task)
 119 {
 120         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 121         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 122 }
 123
 124 void user_disable_single_step(struct task_struct *task)
 125 {
 126         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 127         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 128 }
 129
 130 void user_enable_block_step(struct task_struct *task)
 131 {
 132         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 133         set_tsk_thread_flag(task, TIF_BLOCK_STEP);
 134 }
 135
 136 /*
 137  * Called by kernel/ptrace.c when detaching..
 138  *
 139  * Clear all debugging related fields.
 140  */
 141 void ptrace_disable(struct task_struct *task)
 142 {
 143         memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 144         memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 145         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 146         clear_pt_regs_flag(task_pt_regs(task), PIF_PER_TRAP);
 147         task->thread.per_flags = 0;
 148 }
 149
 150 #define __ADDR_MASK 7
 151
 152 static inline unsigned long __peek_user_per(struct task_struct *child,
 153                                             addr_t addr)
 154 {
 155         struct per_struct_kernel *dummy = NULL;
 156
 157         if (addr == (addr_t) &dummy->cr9)
 158                 /* Control bits of the active per set. */
 159                 return test_thread_flag(TIF_SINGLE_STEP) ?
 160                         PER_EVENT_IFETCH : child->thread.per_user.control;
 161         else if (addr == (addr_t) &dummy->cr10)
 162                 /* Start address of the active per set. */
 163                 return test_thread_flag(TIF_SINGLE_STEP) ?
 164                         0 : child->thread.per_user.start;
 165         else if (addr == (addr_t) &dummy->cr11)
 166                 /* End address of the active per set. */
 167                 return test_thread_flag(TIF_SINGLE_STEP) ?
 168                         -1UL : child->thread.per_user.end;
 169         else if (addr == (addr_t) &dummy->bits)
 170                 /* Single-step bit. */
 171                 return test_thread_flag(TIF_SINGLE_STEP) ?
 172                         (1UL << (BITS_PER_LONG - 1)) : 0;
 173         else if (addr == (addr_t) &dummy->starting_addr)
 174                 /* Start address of the user specified per set. */
 175                 return child->thread.per_user.start;
 176         else if (addr == (addr_t) &dummy->ending_addr)
 177                 /* End address of the user specified per set. */
 178                 return child->thread.per_user.end;
 179         else if (addr == (addr_t) &dummy->perc_atmid)
 180                 /* PER code, ATMID and AI of the last PER trap */
 181                 return (unsigned long)
 182                         child->thread.per_event.cause << (BITS_PER_LONG - 16);
 183         else if (addr == (addr_t) &dummy->address)
 184                 /* Address of the last PER trap */
 185                 return child->thread.per_event.address;
 186         else if (addr == (addr_t) &dummy->access_id)
 187                 /* Access id of the last PER trap */
 188                 return (unsigned long)
 189                         child->thread.per_event.paid << (BITS_PER_LONG - 8);
 190         return 0;
 191 }
 192
 193 /*
 194  * Read the word at offset addr from the user area of a process. The
 195  * trouble here is that the information is littered over different
 196  * locations. The process registers are found on the kernel stack,
 197  * the floating point stuff and the trace settings are stored in
 198  * the task structure. In addition the different structures in
 199  * struct user contain pad bytes that should be read as zeroes.
 200  * Lovely...
 201  */
 202 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 203 {
 204         struct user *dummy = NULL;
 205         addr_t offset, tmp;
 206
 207         if (addr < (addr_t) &dummy->regs.acrs) {
 208                 /*
 209                  * psw and gprs are stored on the stack
 210                  */
 211                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 212                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 213                         /* Return a clean psw mask. */
 214                         tmp &= PSW_MASK_USER | PSW_MASK_RI;
 215                         tmp |= PSW_USER_BITS;
 216                 }
 217
 218         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 219                 /*
 220                  * access registers are stored in the thread structure
 221                  */
 222                 offset = addr - (addr_t) &dummy->regs.acrs;
 223                 /*
 224                  * Very special case: old & broken 64 bit gdb reading
 225                  * from acrs[15]. Result is a 64 bit value. Read the
 226                  * 32 bit acrs[15] value and shift it by 32. Sick...
 227                  */
 228                 if (addr == (addr_t) &dummy->regs.acrs[15])
 229                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 230                 else
 231                         tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 232
 233         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 234                 /*
 235                  * orig_gpr2 is stored on the kernel stack
 236                  */
 237                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 238
 239         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 240                 /*
 241                  * prevent reads of padding hole between
 242                  * orig_gpr2 and fp_regs on s390.
 243                  */
 244                 tmp = 0;
 245
 246         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 247                 /*
 248                  * floating point control reg. is in the thread structure
 249                  */
 250                 tmp = child->thread.fpu.fpc;
 251                 tmp <<= BITS_PER_LONG - 32;
 252
 253         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 254                 /*
 255                  * floating point regs. are either in child->thread.fpu
 256                  * or the child->thread.fpu.vxrs array
 257                  */
 258                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 259                 if (MACHINE_HAS_VX)
 260                         tmp = *(addr_t *)
 261                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 262                 else
 263                         tmp = *(addr_t *)
 264                                ((addr_t) child->thread.fpu.fprs + offset);
 265
 266         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 267                 /*
 268                  * Handle access to the per_info structure.
 269                  */
 270                 addr -= (addr_t) &dummy->regs.per_info;
 271                 tmp = __peek_user_per(child, addr);
 272
 273         } else
 274                 tmp = 0;
 275
 276         return tmp;
 277 }
 278
 279 static int
 280 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 281 {
 282         addr_t tmp, mask;
 283
 284         /*
 285          * Stupid gdb peeks/pokes the access registers in 64 bit with
 286          * an alignment of 4. Programmers from hell...
 287          */
 288         mask = __ADDR_MASK;
 289         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 290             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 291                 mask = 3;
 292         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 293                 return -EIO;
 294
 295         tmp = __peek_user(child, addr);
 296         return put_user(tmp, (addr_t __user *) data);
 297 }
 298
 299 static inline void __poke_user_per(struct task_struct *child,
 300                                    addr_t addr, addr_t data)
 301 {
 302         struct per_struct_kernel *dummy = NULL;
 303
 304         /*
 305          * There are only three fields in the per_info struct that the
 306          * debugger user can write to.
 307          * 1) cr9: the debugger wants to set a new PER event mask
 308          * 2) starting_addr: the debugger wants to set a new starting
 309          *    address to use with the PER event mask.
 310          * 3) ending_addr: the debugger wants to set a new ending
 311          *    address to use with the PER event mask.
 312          * The user specified PER event mask and the start and end
 313          * addresses are used only if single stepping is not in effect.
 314          * Writes to any other field in per_info are ignored.
 315          */
 316         if (addr == (addr_t) &dummy->cr9)
 317                 /* PER event mask of the user specified per set. */
 318                 child->thread.per_user.control =
 319                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 320         else if (addr == (addr_t) &dummy->starting_addr)
 321                 /* Starting address of the user specified per set. */
 322                 child->thread.per_user.start = data;
 323         else if (addr == (addr_t) &dummy->ending_addr)
 324                 /* Ending address of the user specified per set. */
 325                 child->thread.per_user.end = data;
 326 }
 327
 328 static void fixup_int_code(struct task_struct *child, addr_t data)
 329 {
 330         struct pt_regs *regs = task_pt_regs(child);
 331         int ilc = regs->int_code >> 16;
 332         u16 insn;
 333
 334         if (ilc > 6)
 335                 return;
 336
 337         if (ptrace_access_vm(child, regs->psw.addr - (regs->int_code >> 16),
 338                         &insn, sizeof(insn), FOLL_FORCE) != sizeof(insn))
 339                 return;
 340
 341         /* double check that tracee stopped on svc instruction */
 342         if ((insn >> 8) != 0xa)
 343                 return;
 344
 345         regs->int_code = 0x20000 | (data & 0xffff);
 346 }
 347 /*
 348  * Write a word to the user area of a process at location addr. This
 349  * operation does have an additional problem compared to peek_user.
 350  * Stores to the program status word and on the floating point
 351  * control register needs to get checked for validity.
 352  */
 353 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 354 {
 355         struct user *dummy = NULL;
 356         addr_t offset;
 357
 358
 359         if (addr < (addr_t) &dummy->regs.acrs) {
 360                 struct pt_regs *regs = task_pt_regs(child);
 361                 /*
 362                  * psw and gprs are stored on the stack
 363                  */
 364                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 365                         unsigned long mask = PSW_MASK_USER;
 366
 367                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 368                         if ((data ^ PSW_USER_BITS) & ~mask)
 369                                 /* Invalid psw mask. */
 370                                 return -EINVAL;
 371                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 372                                 /* Invalid address-space-control bits */
 373                                 return -EINVAL;
 374                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 375                                 /* Invalid addressing mode bits */
 376                                 return -EINVAL;
 377                 }
 378
 379                 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
 380                         addr == offsetof(struct user, regs.gprs[2]))
 381                         fixup_int_code(child, data);
 382                 *(addr_t *)((addr_t) &regs->psw + addr) = data;
 383
 384         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 385                 /*
 386                  * access registers are stored in the thread structure
 387                  */
 388                 offset = addr - (addr_t) &dummy->regs.acrs;
 389                 /*
 390                  * Very special case: old & broken 64 bit gdb writing
 391                  * to acrs[15] with a 64 bit value. Ignore the lower
 392                  * half of the value and write the upper 32 bit to
 393                  * acrs[15]. Sick...
 394                  */
 395                 if (addr == (addr_t) &dummy->regs.acrs[15])
 396                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 397                 else
 398                         *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 399
 400         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 401                 /*
 402                  * orig_gpr2 is stored on the kernel stack
 403                  */
 404                 task_pt_regs(child)->orig_gpr2 = data;
 405
 406         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 407                 /*
 408                  * prevent writes of padding hole between
 409                  * orig_gpr2 and fp_regs on s390.
 410                  */
 411                 return 0;
 412
 413         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 414                 /*
 415                  * floating point control reg. is in the thread structure
 416                  */
 417                 if ((unsigned int) data != 0 ||
 418                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 419                         return -EINVAL;
 420                 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
 421
 422         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 423                 /*
 424                  * floating point regs. are either in child->thread.fpu
 425                  * or the child->thread.fpu.vxrs array
 426                  */
 427                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 428                 if (MACHINE_HAS_VX)
 429                         *(addr_t *)((addr_t)
 430                                 child->thread.fpu.vxrs + 2*offset) = data;
 431                 else
 432                         *(addr_t *)((addr_t)
 433                                 child->thread.fpu.fprs + offset) = data;
 434
 435         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 436                 /*
 437                  * Handle access to the per_info structure.
 438                  */
 439                 addr -= (addr_t) &dummy->regs.per_info;
 440                 __poke_user_per(child, addr, data);
 441
 442         }
 443
 444         return 0;
 445 }
 446
 447 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 448 {
 449         addr_t mask;
 450
 451         /*
 452          * Stupid gdb peeks/pokes the access registers in 64 bit with
 453          * an alignment of 4. Programmers from hell indeed...
 454          */
 455         mask = __ADDR_MASK;
 456         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 457             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 458                 mask = 3;
 459         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 460                 return -EIO;
 461
 462         return __poke_user(child, addr, data);
 463 }
 464
 465 long arch_ptrace(struct task_struct *child, long request,
 466                  unsigned long addr, unsigned long data)
 467 {
 468         ptrace_area parea;
 469         int copied, ret;
 470
 471         switch (request) {
 472         case PTRACE_PEEKUSR:
 473                 /* read the word at location addr in the USER area. */
 474                 return peek_user(child, addr, data);
 475
 476         case PTRACE_POKEUSR:
 477                 /* write the word at location addr in the USER area */
 478                 return poke_user(child, addr, data);
 479
 480         case PTRACE_PEEKUSR_AREA:
 481         case PTRACE_POKEUSR_AREA:
 482                 if (copy_from_user(&parea, (void __force __user *) addr,
 483                                                         sizeof(parea)))
 484                         return -EFAULT;
 485                 addr = parea.kernel_addr;
 486                 data = parea.process_addr;
 487                 copied = 0;
 488                 while (copied < parea.len) {
 489                         if (request == PTRACE_PEEKUSR_AREA)
 490                                 ret = peek_user(child, addr, data);
 491                         else {
 492                                 addr_t utmp;
 493                                 if (get_user(utmp,
 494                                              (addr_t __force __user *) data))
 495                                         return -EFAULT;
 496                                 ret = poke_user(child, addr, utmp);
 497                         }
 498                         if (ret)
 499                                 return ret;
 500                         addr += sizeof(unsigned long);
 501                         data += sizeof(unsigned long);
 502                         copied += sizeof(unsigned long);
 503                 }
 504                 return 0;
 505         case PTRACE_GET_LAST_BREAK:
 506                 put_user(child->thread.last_break,
 507                          (unsigned long __user *) data);
 508                 return 0;
 509         case PTRACE_ENABLE_TE:
 510                 if (!MACHINE_HAS_TE)
 511                         return -EIO;
 512                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 513                 return 0;
 514         case PTRACE_DISABLE_TE:
 515                 if (!MACHINE_HAS_TE)
 516                         return -EIO;
 517                 child->thread.per_flags |= PER_FLAG_NO_TE;
 518                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 519                 return 0;
 520         case PTRACE_TE_ABORT_RAND:
 521                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 522                         return -EIO;
 523                 switch (data) {
 524                 case 0UL:
 525                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 526                         break;
 527                 case 1UL:
 528                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 529                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 530                         break;
 531                 case 2UL:
 532                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 533                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 534                         break;
 535                 default:
 536                         return -EINVAL;
 537                 }
 538                 return 0;
 539         default:
 540                 return ptrace_request(child, request, addr, data);
 541         }
 542 }
 543
 544 #ifdef CONFIG_COMPAT
 545 /*
 546  * Now the fun part starts... a 31 bit program running in the
 547  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 548  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 549  * to handle, the difference to the 64 bit versions of the requests
 550  * is that the access is done in multiples of 4 byte instead of
 551  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 552  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 553  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 554  * is a 31 bit program too, the content of struct user can be
 555  * emulated. A 31 bit program peeking into the struct user of
 556  * a 64 bit program is a no-no.
 557  */
 558
 559 /*
 560  * Same as peek_user_per but for a 31 bit program.
 561  */
 562 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 563                                            addr_t addr)
 564 {
 565         struct compat_per_struct_kernel *dummy32 = NULL;
 566
 567         if (addr == (addr_t) &dummy32->cr9)
 568                 /* Control bits of the active per set. */
 569                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 570                         PER_EVENT_IFETCH : child->thread.per_user.control;
 571         else if (addr == (addr_t) &dummy32->cr10)
 572                 /* Start address of the active per set. */
 573                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 574                         0 : child->thread.per_user.start;
 575         else if (addr == (addr_t) &dummy32->cr11)
 576                 /* End address of the active per set. */
 577                 return test_thread_flag(TIF_SINGLE_STEP) ?
 578                         PSW32_ADDR_INSN : child->thread.per_user.end;
 579         else if (addr == (addr_t) &dummy32->bits)
 580                 /* Single-step bit. */
 581                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 582                         0x80000000 : 0;
 583         else if (addr == (addr_t) &dummy32->starting_addr)
 584                 /* Start address of the user specified per set. */
 585                 return (__u32) child->thread.per_user.start;
 586         else if (addr == (addr_t) &dummy32->ending_addr)
 587                 /* End address of the user specified per set. */
 588                 return (__u32) child->thread.per_user.end;
 589         else if (addr == (addr_t) &dummy32->perc_atmid)
 590                 /* PER code, ATMID and AI of the last PER trap */
 591                 return (__u32) child->thread.per_event.cause << 16;
 592         else if (addr == (addr_t) &dummy32->address)
 593                 /* Address of the last PER trap */
 594                 return (__u32) child->thread.per_event.address;
 595         else if (addr == (addr_t) &dummy32->access_id)
 596                 /* Access id of the last PER trap */
 597                 return (__u32) child->thread.per_event.paid << 24;
 598         return 0;
 599 }
 600
 601 /*
 602  * Same as peek_user but for a 31 bit program.
 603  */
 604 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 605 {
 606         struct compat_user *dummy32 = NULL;
 607         addr_t offset;
 608         __u32 tmp;
 609
 610         if (addr < (addr_t) &dummy32->regs.acrs) {
 611                 struct pt_regs *regs = task_pt_regs(child);
 612                 /*
 613                  * psw and gprs are stored on the stack
 614                  */
 615                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 616                         /* Fake a 31 bit psw mask. */
 617                         tmp = (__u32)(regs->psw.mask >> 32);
 618                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 619                         tmp |= PSW32_USER_BITS;
 620                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 621                         /* Fake a 31 bit psw address. */
 622                         tmp = (__u32) regs->psw.addr |
 623                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 624                 } else {
 625                         /* gpr 0-15 */
 626                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 627                 }
 628         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 629                 /*
 630                  * access registers are stored in the thread structure
 631                  */
 632                 offset = addr - (addr_t) &dummy32->regs.acrs;
 633                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 634
 635         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 636                 /*
 637                  * orig_gpr2 is stored on the kernel stack
 638                  */
 639                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 640
 641         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 642                 /*
 643                  * prevent reads of padding hole between
 644                  * orig_gpr2 and fp_regs on s390.
 645                  */
 646                 tmp = 0;
 647
 648         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 649                 /*
 650                  * floating point control reg. is in the thread structure
 651                  */
 652                 tmp = child->thread.fpu.fpc;
 653
 654         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 655                 /*
 656                  * floating point regs. are either in child->thread.fpu
 657                  * or the child->thread.fpu.vxrs array
 658                  */
 659                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 660                 if (MACHINE_HAS_VX)
 661                         tmp = *(__u32 *)
 662                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 663                 else
 664                         tmp = *(__u32 *)
 665                                ((addr_t) child->thread.fpu.fprs + offset);
 666
 667         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 668                 /*
 669                  * Handle access to the per_info structure.
 670                  */
 671                 addr -= (addr_t) &dummy32->regs.per_info;
 672                 tmp = __peek_user_per_compat(child, addr);
 673
 674         } else
 675                 tmp = 0;
 676
 677         return tmp;
 678 }
 679
 680 static int peek_user_compat(struct task_struct *child,
 681                             addr_t addr, addr_t data)
 682 {
 683         __u32 tmp;
 684
 685         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 686                 return -EIO;
 687
 688         tmp = __peek_user_compat(child, addr);
 689         return put_user(tmp, (__u32 __user *) data);
 690 }
 691
 692 /*
 693  * Same as poke_user_per but for a 31 bit program.
 694  */
 695 static inline void __poke_user_per_compat(struct task_struct *child,
 696                                           addr_t addr, __u32 data)
 697 {
 698         struct compat_per_struct_kernel *dummy32 = NULL;
 699
 700         if (addr == (addr_t) &dummy32->cr9)
 701                 /* PER event mask of the user specified per set. */
 702                 child->thread.per_user.control =
 703                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 704         else if (addr == (addr_t) &dummy32->starting_addr)
 705                 /* Starting address of the user specified per set. */
 706                 child->thread.per_user.start = data;
 707         else if (addr == (addr_t) &dummy32->ending_addr)
 708                 /* Ending address of the user specified per set. */
 709                 child->thread.per_user.end = data;
 710 }
 711
 712 /*
 713  * Same as poke_user but for a 31 bit program.
 714  */
 715 static int __poke_user_compat(struct task_struct *child,
 716                               addr_t addr, addr_t data)
 717 {
 718         struct compat_user *dummy32 = NULL;
 719         __u32 tmp = (__u32) data;
 720         addr_t offset;
 721
 722         if (addr < (addr_t) &dummy32->regs.acrs) {
 723                 struct pt_regs *regs = task_pt_regs(child);
 724                 /*
 725                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 726                  */
 727                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 728                         __u32 mask = PSW32_MASK_USER;
 729
 730                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 731                         /* Build a 64 bit psw mask from 31 bit mask. */
 732                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 733                                 /* Invalid psw mask. */
 734                                 return -EINVAL;
 735                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 736                                 /* Invalid address-space-control bits */
 737                                 return -EINVAL;
 738                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 739                                 (regs->psw.mask & PSW_MASK_BA) |
 740                                 (__u64)(tmp & mask) << 32;
 741                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 742                         /* Build a 64 bit psw address from 31 bit address. */
 743                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 744                         /* Transfer 31 bit amode bit to psw mask. */
 745                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 746                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 747                 } else {
 748
 749                         if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
 750                                 addr == offsetof(struct compat_user, regs.gprs[2]))
 751                                 fixup_int_code(child, data);
 752                         /* gpr 0-15 */
 753                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 754                 }
 755         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 756                 /*
 757                  * access registers are stored in the thread structure
 758                  */
 759                 offset = addr - (addr_t) &dummy32->regs.acrs;
 760                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 761
 762         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 763                 /*
 764                  * orig_gpr2 is stored on the kernel stack
 765                  */
 766                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 767
 768         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 769                 /*
 770                  * prevent writess of padding hole between
 771                  * orig_gpr2 and fp_regs on s390.
 772                  */
 773                 return 0;
 774
 775         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 776                 /*
 777                  * floating point control reg. is in the thread structure
 778                  */
 779                 if (test_fp_ctl(tmp))
 780                         return -EINVAL;
 781                 child->thread.fpu.fpc = data;
 782
 783         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 784                 /*
 785                  * floating point regs. are either in child->thread.fpu
 786                  * or the child->thread.fpu.vxrs array
 787                  */
 788                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 789                 if (MACHINE_HAS_VX)
 790                         *(__u32 *)((addr_t)
 791                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 792                 else
 793                         *(__u32 *)((addr_t)
 794                                 child->thread.fpu.fprs + offset) = tmp;
 795
 796         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 797                 /*
 798                  * Handle access to the per_info structure.
 799                  */
 800                 addr -= (addr_t) &dummy32->regs.per_info;
 801                 __poke_user_per_compat(child, addr, data);
 802         }
 803
 804         return 0;
 805 }
 806
 807 static int poke_user_compat(struct task_struct *child,
 808                             addr_t addr, addr_t data)
 809 {
 810         if (!is_compat_task() || (addr & 3) ||
 811             addr > sizeof(struct compat_user) - 3)
 812                 return -EIO;
 813
 814         return __poke_user_compat(child, addr, data);
 815 }
 816
 817 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 818                         compat_ulong_t caddr, compat_ulong_t cdata)
 819 {
 820         unsigned long addr = caddr;
 821         unsigned long data = cdata;
 822         compat_ptrace_area parea;
 823         int copied, ret;
 824
 825         switch (request) {
 826         case PTRACE_PEEKUSR:
 827                 /* read the word at location addr in the USER area. */
 828                 return peek_user_compat(child, addr, data);
 829
 830         case PTRACE_POKEUSR:
 831                 /* write the word at location addr in the USER area */
 832                 return poke_user_compat(child, addr, data);
 833
 834         case PTRACE_PEEKUSR_AREA:
 835         case PTRACE_POKEUSR_AREA:
 836                 if (copy_from_user(&parea, (void __force __user *) addr,
 837                                                         sizeof(parea)))
 838                         return -EFAULT;
 839                 addr = parea.kernel_addr;
 840                 data = parea.process_addr;
 841                 copied = 0;
 842                 while (copied < parea.len) {
 843                         if (request == PTRACE_PEEKUSR_AREA)
 844                                 ret = peek_user_compat(child, addr, data);
 845                         else {
 846                                 __u32 utmp;
 847                                 if (get_user(utmp,
 848                                              (__u32 __force __user *) data))
 849                                         return -EFAULT;
 850                                 ret = poke_user_compat(child, addr, utmp);
 851                         }
 852                         if (ret)
 853                                 return ret;
 854                         addr += sizeof(unsigned int);
 855                         data += sizeof(unsigned int);
 856                         copied += sizeof(unsigned int);
 857                 }
 858                 return 0;
 859         case PTRACE_GET_LAST_BREAK:
 860                 put_user(child->thread.last_break,
 861                          (unsigned int __user *) data);
 862                 return 0;
 863         }
 864         return compat_ptrace_request(child, request, addr, data);
 865 }
 866 #endif
 867
 868 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 869 {
 870         unsigned long mask = -1UL;
 871
 872         /*
 873          * The sysc_tracesys code in entry.S stored the system
 874          * call number to gprs[2].
 875          */
 876         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 877             (tracehook_report_syscall_entry(regs) ||
 878              regs->gprs[2] >= NR_syscalls)) {
 879                 /*
 880                  * Tracing decided this syscall should not happen or the
 881                  * debugger stored an invalid system call number. Skip
 882                  * the system call and the system call restart handling.
 883                  */
 884                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 885                 return -1;
 886         }
 887
 888         /* Do the secure computing check after ptrace. */
 889         if (secure_computing(NULL)) {
 890                 /* seccomp failures shouldn't expose any additional code. */
 891                 return -1;
 892         }
 893
 894         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 895                 trace_sys_enter(regs, regs->gprs[2]);
 896
 897         if (is_compat_task())
 898                 mask = 0xffffffff;
 899
 900         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
 901                             regs->gprs[3] &mask, regs->gprs[4] &mask,
 902                             regs->gprs[5] &mask);
 903
 904         return regs->gprs[2];
 905 }
 906
 907 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 908 {
 909         audit_syscall_exit(regs);
 910
 911         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 912                 trace_sys_exit(regs, regs->gprs[2]);
 913
 914         if (test_thread_flag(TIF_SYSCALL_TRACE))
 915                 tracehook_report_syscall_exit(regs, 0);
 916 }
 917
 918 /*
 919  * user_regset definitions.
 920  */
 921
 922 static int s390_regs_get(struct task_struct *target,
 923                          const struct user_regset *regset,
 924                          unsigned int pos, unsigned int count,
 925                          void *kbuf, void __user *ubuf)
 926 {
 927         if (target == current)
 928                 save_access_regs(target->thread.acrs);
 929
 930         if (kbuf) {
 931                 unsigned long *k = kbuf;
 932                 while (count > 0) {
 933                         *k++ = __peek_user(target, pos);
 934                         count -= sizeof(*k);
 935                         pos += sizeof(*k);
 936                 }
 937         } else {
 938                 unsigned long __user *u = ubuf;
 939                 while (count > 0) {
 940                         if (__put_user(__peek_user(target, pos), u++))
 941                                 return -EFAULT;
 942                         count -= sizeof(*u);
 943                         pos += sizeof(*u);
 944                 }
 945         }
 946         return 0;
 947 }
 948
 949 static int s390_regs_set(struct task_struct *target,
 950                          const struct user_regset *regset,
 951                          unsigned int pos, unsigned int count,
 952                          const void *kbuf, const void __user *ubuf)
 953 {
 954         int rc = 0;
 955
 956         if (target == current)
 957                 save_access_regs(target->thread.acrs);
 958
 959         if (kbuf) {
 960                 const unsigned long *k = kbuf;
 961                 while (count > 0 && !rc) {
 962                         rc = __poke_user(target, pos, *k++);
 963                         count -= sizeof(*k);
 964                         pos += sizeof(*k);
 965                 }
 966         } else {
 967                 const unsigned long  __user *u = ubuf;
 968                 while (count > 0 && !rc) {
 969                         unsigned long word;
 970                         rc = __get_user(word, u++);
 971                         if (rc)
 972                                 break;
 973                         rc = __poke_user(target, pos, word);
 974                         count -= sizeof(*u);
 975                         pos += sizeof(*u);
 976                 }
 977         }
 978
 979         if (rc == 0 && target == current)
 980                 restore_access_regs(target->thread.acrs);
 981
 982         return rc;
 983 }
 984
 985 static int s390_fpregs_get(struct task_struct *target,
 986                            const struct user_regset *regset, unsigned int pos,
 987                            unsigned int count, void *kbuf, void __user *ubuf)
 988 {
 989         _s390_fp_regs fp_regs;
 990
 991         if (target == current)
 992                 save_fpu_regs();
 993
 994         fp_regs.fpc = target->thread.fpu.fpc;
 995         fpregs_store(&fp_regs, &target->thread.fpu);
 996
 997         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 998                                    &fp_regs, 0, -1);
 999 }
1000
1001 static int s390_fpregs_set(struct task_struct *target,
1002                            const struct user_regset *regset, unsigned int pos,
1003                            unsigned int count, const void *kbuf,
1004                            const void __user *ubuf)
1005 {
1006         int rc = 0;
1007         freg_t fprs[__NUM_FPRS];
1008
1009         if (target == current)
1010                 save_fpu_regs();
1011
1012         if (MACHINE_HAS_VX)
1013                 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
1014         else
1015                 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
1016
1017         /* If setting FPC, must validate it first. */
1018         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
1019                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
1020                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
1021                                         0, offsetof(s390_fp_regs, fprs));
1022                 if (rc)
1023                         return rc;
1024                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
1025                         return -EINVAL;
1026                 target->thread.fpu.fpc = ufpc[0];
1027         }
1028
1029         if (rc == 0 && count > 0)
1030                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1031                                         fprs, offsetof(s390_fp_regs, fprs), -1);
1032         if (rc)
1033                 return rc;
1034
1035         if (MACHINE_HAS_VX)
1036                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
1037         else
1038                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
1039
1040         return rc;
1041 }
1042
1043 static int s390_last_break_get(struct task_struct *target,
1044                                const struct user_regset *regset,
1045                                unsigned int pos, unsigned int count,
1046                                void *kbuf, void __user *ubuf)
1047 {
1048         if (count > 0) {
1049                 if (kbuf) {
1050                         unsigned long *k = kbuf;
1051                         *k = target->thread.last_break;
1052                 } else {
1053                         unsigned long  __user *u = ubuf;
1054                         if (__put_user(target->thread.last_break, u))
1055                                 return -EFAULT;
1056                 }
1057         }
1058         return 0;
1059 }
1060
1061 static int s390_last_break_set(struct task_struct *target,
1062                                const struct user_regset *regset,
1063                                unsigned int pos, unsigned int count,
1064                                const void *kbuf, const void __user *ubuf)
1065 {
1066         return 0;
1067 }
1068
1069 static int s390_tdb_get(struct task_struct *target,
1070                         const struct user_regset *regset,
1071                         unsigned int pos, unsigned int count,
1072                         void *kbuf, void __user *ubuf)
1073 {
1074         struct pt_regs *regs = task_pt_regs(target);
1075         unsigned char *data;
1076
1077         if (!(regs->int_code & 0x200))
1078                 return -ENODATA;
1079         data = target->thread.trap_tdb;
1080         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1081 }
1082
1083 static int s390_tdb_set(struct task_struct *target,
1084                         const struct user_regset *regset,
1085                         unsigned int pos, unsigned int count,
1086                         const void *kbuf, const void __user *ubuf)
1087 {
1088         return 0;
1089 }
1090
1091 static int s390_vxrs_low_get(struct task_struct *target,
1092                              const struct user_regset *regset,
1093                              unsigned int pos, unsigned int count,
1094                              void *kbuf, void __user *ubuf)
1095 {
1096         __u64 vxrs[__NUM_VXRS_LOW];
1097         int i;
1098
1099         if (!MACHINE_HAS_VX)
1100                 return -ENODEV;
1101         if (target == current)
1102                 save_fpu_regs();
1103         for (i = 0; i < __NUM_VXRS_LOW; i++)
1104                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1105         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1106 }
1107
1108 static int s390_vxrs_low_set(struct task_struct *target,
1109                              const struct user_regset *regset,
1110                              unsigned int pos, unsigned int count,
1111                              const void *kbuf, const void __user *ubuf)
1112 {
1113         __u64 vxrs[__NUM_VXRS_LOW];
1114         int i, rc;
1115
1116         if (!MACHINE_HAS_VX)
1117                 return -ENODEV;
1118         if (target == current)
1119                 save_fpu_regs();
1120
1121         for (i = 0; i < __NUM_VXRS_LOW; i++)
1122                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1123
1124         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1125         if (rc == 0)
1126                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1127                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1128
1129         return rc;
1130 }
1131
1132 static int s390_vxrs_high_get(struct task_struct *target,
1133                               const struct user_regset *regset,
1134                               unsigned int pos, unsigned int count,
1135                               void *kbuf, void __user *ubuf)
1136 {
1137         __vector128 vxrs[__NUM_VXRS_HIGH];
1138
1139         if (!MACHINE_HAS_VX)
1140                 return -ENODEV;
1141         if (target == current)
1142                 save_fpu_regs();
1143         memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1144
1145         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1146 }
1147
1148 static int s390_vxrs_high_set(struct task_struct *target,
1149                               const struct user_regset *regset,
1150                               unsigned int pos, unsigned int count,
1151                               const void *kbuf, const void __user *ubuf)
1152 {
1153         int rc;
1154
1155         if (!MACHINE_HAS_VX)
1156                 return -ENODEV;
1157         if (target == current)
1158                 save_fpu_regs();
1159
1160         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1161                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1162         return rc;
1163 }
1164
1165 static int s390_system_call_get(struct task_struct *target,
1166                                 const struct user_regset *regset,
1167                                 unsigned int pos, unsigned int count,
1168                                 void *kbuf, void __user *ubuf)
1169 {
1170         unsigned int *data = &target->thread.system_call;
1171         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1172                                    data, 0, sizeof(unsigned int));
1173 }
1174
1175 static int s390_system_call_set(struct task_struct *target,
1176                                 const struct user_regset *regset,
1177                                 unsigned int pos, unsigned int count,
1178                                 const void *kbuf, const void __user *ubuf)
1179 {
1180         unsigned int *data = &target->thread.system_call;
1181         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1182                                   data, 0, sizeof(unsigned int));
1183 }
1184
1185 static int s390_gs_cb_get(struct task_struct *target,
1186                           const struct user_regset *regset,
1187                           unsigned int pos, unsigned int count,
1188                           void *kbuf, void __user *ubuf)
1189 {
1190         struct gs_cb *data = target->thread.gs_cb;
1191
1192         if (!MACHINE_HAS_GS)
1193                 return -ENODEV;
1194         if (!data)
1195                 return -ENODATA;
1196         if (target == current)
1197                 save_gs_cb(data);
1198         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1199                                    data, 0, sizeof(struct gs_cb));
1200 }
1201
1202 static int s390_gs_cb_set(struct task_struct *target,
1203                           const struct user_regset *regset,
1204                           unsigned int pos, unsigned int count,
1205                           const void *kbuf, const void __user *ubuf)
1206 {
1207         struct gs_cb gs_cb = { }, *data = NULL;
1208         int rc;
1209
1210         if (!MACHINE_HAS_GS)
1211                 return -ENODEV;
1212         if (!target->thread.gs_cb) {
1213                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1214                 if (!data)
1215                         return -ENOMEM;
1216         }
1217         if (!target->thread.gs_cb)
1218                 gs_cb.gsd = 25;
1219         else if (target == current)
1220                 save_gs_cb(&gs_cb);
1221         else
1222                 gs_cb = *target->thread.gs_cb;
1223         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1224                                 &gs_cb, 0, sizeof(gs_cb));
1225         if (rc) {
1226                 kfree(data);
1227                 return -EFAULT;
1228         }
1229         preempt_disable();
1230         if (!target->thread.gs_cb)
1231                 target->thread.gs_cb = data;
1232         *target->thread.gs_cb = gs_cb;
1233         if (target == current) {
1234                 __ctl_set_bit(2, 4);
1235                 restore_gs_cb(target->thread.gs_cb);
1236         }
1237         preempt_enable();
1238         return rc;
1239 }
1240
1241 static int s390_gs_bc_get(struct task_struct *target,
1242                           const struct user_regset *regset,
1243                           unsigned int pos, unsigned int count,
1244                           void *kbuf, void __user *ubuf)
1245 {
1246         struct gs_cb *data = target->thread.gs_bc_cb;
1247
1248         if (!MACHINE_HAS_GS)
1249                 return -ENODEV;
1250         if (!data)
1251                 return -ENODATA;
1252         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1253                                    data, 0, sizeof(struct gs_cb));
1254 }
1255
1256 static int s390_gs_bc_set(struct task_struct *target,
1257                           const struct user_regset *regset,
1258                           unsigned int pos, unsigned int count,
1259                           const void *kbuf, const void __user *ubuf)
1260 {
1261         struct gs_cb *data = target->thread.gs_bc_cb;
1262
1263         if (!MACHINE_HAS_GS)
1264                 return -ENODEV;
1265         if (!data) {
1266                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1267                 if (!data)
1268                         return -ENOMEM;
1269                 target->thread.gs_bc_cb = data;
1270         }
1271         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1272                                   data, 0, sizeof(struct gs_cb));
1273 }
1274
1275 static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1276 {
1277         return (cb->rca & 0x1f) == 0 &&
1278                 (cb->roa & 0xfff) == 0 &&
1279                 (cb->rla & 0xfff) == 0xfff &&
1280                 cb->s == 1 &&
1281                 cb->k == 1 &&
1282                 cb->h == 0 &&
1283                 cb->reserved1 == 0 &&
1284                 cb->ps == 1 &&
1285                 cb->qs == 0 &&
1286                 cb->pc == 1 &&
1287                 cb->qc == 0 &&
1288                 cb->reserved2 == 0 &&
1289                 cb->reserved3 == 0 &&
1290                 cb->reserved4 == 0 &&
1291                 cb->reserved5 == 0 &&
1292                 cb->reserved6 == 0 &&
1293                 cb->reserved7 == 0 &&
1294                 cb->reserved8 == 0 &&
1295                 cb->rla >= cb->roa &&
1296                 cb->rca >= cb->roa &&
1297                 cb->rca <= cb->rla+1 &&
1298                 cb->m < 3;
1299 }
1300
1301 static int s390_runtime_instr_get(struct task_struct *target,
1302                                 const struct user_regset *regset,
1303                                 unsigned int pos, unsigned int count,
1304                                 void *kbuf, void __user *ubuf)
1305 {
1306         struct runtime_instr_cb *data = target->thread.ri_cb;
1307
1308         if (!test_facility(64))
1309                 return -ENODEV;
1310         if (!data)
1311                 return -ENODATA;
1312
1313         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1314                                    data, 0, sizeof(struct runtime_instr_cb));
1315 }
1316
1317 static int s390_runtime_instr_set(struct task_struct *target,
1318                                   const struct user_regset *regset,
1319                                   unsigned int pos, unsigned int count,
1320                                   const void *kbuf, const void __user *ubuf)
1321 {
1322         struct runtime_instr_cb ri_cb = { }, *data = NULL;
1323         int rc;
1324
1325         if (!test_facility(64))
1326                 return -ENODEV;
1327
1328         if (!target->thread.ri_cb) {
1329                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1330                 if (!data)
1331                         return -ENOMEM;
1332         }
1333
1334         if (target->thread.ri_cb) {
1335                 if (target == current)
1336                         store_runtime_instr_cb(&ri_cb);
1337                 else
1338                         ri_cb = *target->thread.ri_cb;
1339         }
1340
1341         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1342                                 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1343         if (rc) {
1344                 kfree(data);
1345                 return -EFAULT;
1346         }
1347
1348         if (!is_ri_cb_valid(&ri_cb)) {
1349                 kfree(data);
1350                 return -EINVAL;
1351         }
1352         /*
1353          * Override access key in any case, since user space should
1354          * not be able to set it, nor should it care about it.
1355          */
1356         ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1357         preempt_disable();
1358         if (!target->thread.ri_cb)
1359                 target->thread.ri_cb = data;
1360         *target->thread.ri_cb = ri_cb;
1361         if (target == current)
1362                 load_runtime_instr_cb(target->thread.ri_cb);
1363         preempt_enable();
1364
1365         return 0;
1366 }
1367
1368 static const struct user_regset s390_regsets[] = {
1369         {
1370                 .core_note_type = NT_PRSTATUS,
1371                 .n = sizeof(s390_regs) / sizeof(long),
1372                 .size = sizeof(long),
1373                 .align = sizeof(long),
1374                 .get = s390_regs_get,
1375                 .set = s390_regs_set,
1376         },
1377         {
1378                 .core_note_type = NT_PRFPREG,
1379                 .n = sizeof(s390_fp_regs) / sizeof(long),
1380                 .size = sizeof(long),
1381                 .align = sizeof(long),
1382                 .get = s390_fpregs_get,
1383                 .set = s390_fpregs_set,
1384         },
1385         {
1386                 .core_note_type = NT_S390_SYSTEM_CALL,
1387                 .n = 1,
1388                 .size = sizeof(unsigned int),
1389                 .align = sizeof(unsigned int),
1390                 .get = s390_system_call_get,
1391                 .set = s390_system_call_set,
1392         },
1393         {
1394                 .core_note_type = NT_S390_LAST_BREAK,
1395                 .n = 1,
1396                 .size = sizeof(long),
1397                 .align = sizeof(long),
1398                 .get = s390_last_break_get,
1399                 .set = s390_last_break_set,
1400         },
1401         {
1402                 .core_note_type = NT_S390_TDB,
1403                 .n = 1,
1404                 .size = 256,
1405                 .align = 1,
1406                 .get = s390_tdb_get,
1407                 .set = s390_tdb_set,
1408         },
1409         {
1410                 .core_note_type = NT_S390_VXRS_LOW,
1411                 .n = __NUM_VXRS_LOW,
1412                 .size = sizeof(__u64),
1413                 .align = sizeof(__u64),
1414                 .get = s390_vxrs_low_get,
1415                 .set = s390_vxrs_low_set,
1416         },
1417         {
1418                 .core_note_type = NT_S390_VXRS_HIGH,
1419                 .n = __NUM_VXRS_HIGH,
1420                 .size = sizeof(__vector128),
1421                 .align = sizeof(__vector128),
1422                 .get = s390_vxrs_high_get,
1423                 .set = s390_vxrs_high_set,
1424         },
1425         {
1426                 .core_note_type = NT_S390_GS_CB,
1427                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1428                 .size = sizeof(__u64),
1429                 .align = sizeof(__u64),
1430                 .get = s390_gs_cb_get,
1431                 .set = s390_gs_cb_set,
1432         },
1433         {
1434                 .core_note_type = NT_S390_GS_BC,
1435                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1436                 .size = sizeof(__u64),
1437                 .align = sizeof(__u64),
1438                 .get = s390_gs_bc_get,
1439                 .set = s390_gs_bc_set,
1440         },
1441         {
1442                 .core_note_type = NT_S390_RI_CB,
1443                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1444                 .size = sizeof(__u64),
1445                 .align = sizeof(__u64),
1446                 .get = s390_runtime_instr_get,
1447                 .set = s390_runtime_instr_set,
1448         },
1449 };
1450
1451 static const struct user_regset_view user_s390_view = {
1452         .name = UTS_MACHINE,
1453         .e_machine = EM_S390,
1454         .regsets = s390_regsets,
1455         .n = ARRAY_SIZE(s390_regsets)
1456 };
1457
1458 #ifdef CONFIG_COMPAT
1459 static int s390_compat_regs_get(struct task_struct *target,
1460                                 const struct user_regset *regset,
1461                                 unsigned int pos, unsigned int count,
1462                                 void *kbuf, void __user *ubuf)
1463 {
1464         if (target == current)
1465                 save_access_regs(target->thread.acrs);
1466
1467         if (kbuf) {
1468                 compat_ulong_t *k = kbuf;
1469                 while (count > 0) {
1470                         *k++ = __peek_user_compat(target, pos);
1471                         count -= sizeof(*k);
1472                         pos += sizeof(*k);
1473                 }
1474         } else {
1475                 compat_ulong_t __user *u = ubuf;
1476                 while (count > 0) {
1477                         if (__put_user(__peek_user_compat(target, pos), u++))
1478                                 return -EFAULT;
1479                         count -= sizeof(*u);
1480                         pos += sizeof(*u);
1481                 }
1482         }
1483         return 0;
1484 }
1485
1486 static int s390_compat_regs_set(struct task_struct *target,
1487                                 const struct user_regset *regset,
1488                                 unsigned int pos, unsigned int count,
1489                                 const void *kbuf, const void __user *ubuf)
1490 {
1491         int rc = 0;
1492
1493         if (target == current)
1494                 save_access_regs(target->thread.acrs);
1495
1496         if (kbuf) {
1497                 const compat_ulong_t *k = kbuf;
1498                 while (count > 0 && !rc) {
1499                         rc = __poke_user_compat(target, pos, *k++);
1500                         count -= sizeof(*k);
1501                         pos += sizeof(*k);
1502                 }
1503         } else {
1504                 const compat_ulong_t  __user *u = ubuf;
1505                 while (count > 0 && !rc) {
1506                         compat_ulong_t word;
1507                         rc = __get_user(word, u++);
1508                         if (rc)
1509                                 break;
1510                         rc = __poke_user_compat(target, pos, word);
1511                         count -= sizeof(*u);
1512                         pos += sizeof(*u);
1513                 }
1514         }
1515
1516         if (rc == 0 && target == current)
1517                 restore_access_regs(target->thread.acrs);
1518
1519         return rc;
1520 }
1521
1522 static int s390_compat_regs_high_get(struct task_struct *target,
1523                                      const struct user_regset *regset,
1524                                      unsigned int pos, unsigned int count,
1525                                      void *kbuf, void __user *ubuf)
1526 {
1527         compat_ulong_t *gprs_high;
1528
1529         gprs_high = (compat_ulong_t *)
1530                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1531         if (kbuf) {
1532                 compat_ulong_t *k = kbuf;
1533                 while (count > 0) {
1534                         *k++ = *gprs_high;
1535                         gprs_high += 2;
1536                         count -= sizeof(*k);
1537                 }
1538         } else {
1539                 compat_ulong_t __user *u = ubuf;
1540                 while (count > 0) {
1541                         if (__put_user(*gprs_high, u++))
1542                                 return -EFAULT;
1543                         gprs_high += 2;
1544                         count -= sizeof(*u);
1545                 }
1546         }
1547         return 0;
1548 }
1549
1550 static int s390_compat_regs_high_set(struct task_struct *target,
1551                                      const struct user_regset *regset,
1552                                      unsigned int pos, unsigned int count,
1553                                      const void *kbuf, const void __user *ubuf)
1554 {
1555         compat_ulong_t *gprs_high;
1556         int rc = 0;
1557
1558         gprs_high = (compat_ulong_t *)
1559                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1560         if (kbuf) {
1561                 const compat_ulong_t *k = kbuf;
1562                 while (count > 0) {
1563                         *gprs_high = *k++;
1564                         *gprs_high += 2;
1565                         count -= sizeof(*k);
1566                 }
1567         } else {
1568                 const compat_ulong_t  __user *u = ubuf;
1569                 while (count > 0 && !rc) {
1570                         unsigned long word;
1571                         rc = __get_user(word, u++);
1572                         if (rc)
1573                                 break;
1574                         *gprs_high = word;
1575                         *gprs_high += 2;
1576                         count -= sizeof(*u);
1577                 }
1578         }
1579
1580         return rc;
1581 }
1582
1583 static int s390_compat_last_break_get(struct task_struct *target,
1584                                       const struct user_regset *regset,
1585                                       unsigned int pos, unsigned int count,
1586                                       void *kbuf, void __user *ubuf)
1587 {
1588         compat_ulong_t last_break;
1589
1590         if (count > 0) {
1591                 last_break = target->thread.last_break;
1592                 if (kbuf) {
1593                         unsigned long *k = kbuf;
1594                         *k = last_break;
1595                 } else {
1596                         unsigned long  __user *u = ubuf;
1597                         if (__put_user(last_break, u))
1598                                 return -EFAULT;
1599                 }
1600         }
1601         return 0;
1602 }
1603
1604 static int s390_compat_last_break_set(struct task_struct *target,
1605                                       const struct user_regset *regset,
1606                                       unsigned int pos, unsigned int count,
1607                                       const void *kbuf, const void __user *ubuf)
1608 {
1609         return 0;
1610 }
1611
1612 static const struct user_regset s390_compat_regsets[] = {
1613         {
1614                 .core_note_type = NT_PRSTATUS,
1615                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1616                 .size = sizeof(compat_long_t),
1617                 .align = sizeof(compat_long_t),
1618                 .get = s390_compat_regs_get,
1619                 .set = s390_compat_regs_set,
1620         },
1621         {
1622                 .core_note_type = NT_PRFPREG,
1623                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1624                 .size = sizeof(compat_long_t),
1625                 .align = sizeof(compat_long_t),
1626                 .get = s390_fpregs_get,
1627                 .set = s390_fpregs_set,
1628         },
1629         {
1630                 .core_note_type = NT_S390_SYSTEM_CALL,
1631                 .n = 1,
1632                 .size = sizeof(compat_uint_t),
1633                 .align = sizeof(compat_uint_t),
1634                 .get = s390_system_call_get,
1635                 .set = s390_system_call_set,
1636         },
1637         {
1638                 .core_note_type = NT_S390_LAST_BREAK,
1639                 .n = 1,
1640                 .size = sizeof(long),
1641                 .align = sizeof(long),
1642                 .get = s390_compat_last_break_get,
1643                 .set = s390_compat_last_break_set,
1644         },
1645         {
1646                 .core_note_type = NT_S390_TDB,
1647                 .n = 1,
1648                 .size = 256,
1649                 .align = 1,
1650                 .get = s390_tdb_get,
1651                 .set = s390_tdb_set,
1652         },
1653         {
1654                 .core_note_type = NT_S390_VXRS_LOW,
1655                 .n = __NUM_VXRS_LOW,
1656                 .size = sizeof(__u64),
1657                 .align = sizeof(__u64),
1658                 .get = s390_vxrs_low_get,
1659                 .set = s390_vxrs_low_set,
1660         },
1661         {
1662                 .core_note_type = NT_S390_VXRS_HIGH,
1663                 .n = __NUM_VXRS_HIGH,
1664                 .size = sizeof(__vector128),
1665                 .align = sizeof(__vector128),
1666                 .get = s390_vxrs_high_get,
1667                 .set = s390_vxrs_high_set,
1668         },
1669         {
1670                 .core_note_type = NT_S390_HIGH_GPRS,
1671                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1672                 .size = sizeof(compat_long_t),
1673                 .align = sizeof(compat_long_t),
1674                 .get = s390_compat_regs_high_get,
1675                 .set = s390_compat_regs_high_set,
1676         },
1677         {
1678                 .core_note_type = NT_S390_GS_CB,
1679                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1680                 .size = sizeof(__u64),
1681                 .align = sizeof(__u64),
1682                 .get = s390_gs_cb_get,
1683                 .set = s390_gs_cb_set,
1684         },
1685         {
1686                 .core_note_type = NT_S390_GS_BC,
1687                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1688                 .size = sizeof(__u64),
1689                 .align = sizeof(__u64),
1690                 .get = s390_gs_bc_get,
1691                 .set = s390_gs_bc_set,
1692         },
1693         {
1694                 .core_note_type = NT_S390_RI_CB,
1695                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1696                 .size = sizeof(__u64),
1697                 .align = sizeof(__u64),
1698                 .get = s390_runtime_instr_get,
1699                 .set = s390_runtime_instr_set,
1700         },
1701 };
1702
1703 static const struct user_regset_view user_s390_compat_view = {
1704         .name = "s390",
1705         .e_machine = EM_S390,
1706         .regsets = s390_compat_regsets,
1707         .n = ARRAY_SIZE(s390_compat_regsets)
1708 };
1709 #endif
1710
1711 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1712 {
1713 #ifdef CONFIG_COMPAT
1714         if (test_tsk_thread_flag(task, TIF_31BIT))
1715                 return &user_s390_compat_view;
1716 #endif
1717         return &user_s390_view;
1718 }
1719
1720 static const char *gpr_names[NUM_GPRS] = {
1721         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1722         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1723 };
1724
1725 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1726 {
1727         if (offset >= NUM_GPRS)
1728                 return 0;
1729         return regs->gprs[offset];
1730 }
1731
1732 int regs_query_register_offset(const char *name)
1733 {
1734         unsigned long offset;
1735
1736         if (!name || *name != 'r')
1737                 return -EINVAL;
1738         if (kstrtoul(name + 1, 10, &offset))
1739                 return -EINVAL;
1740         if (offset >= NUM_GPRS)
1741                 return -EINVAL;
1742         return offset;
1743 }
1744
1745 const char *regs_query_register_name(unsigned int offset)
1746 {
1747         if (offset >= NUM_GPRS)
1748                 return NULL;
1749         return gpr_names[offset];
1750 }
1751
1752 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1753 {
1754         unsigned long ksp = kernel_stack_pointer(regs);
1755
1756         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1757 }
1758
1759 /**
1760  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1761  * @regs:pt_regs which contains kernel stack pointer.
1762  * @n:stack entry number.
1763  *
1764  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1765  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1766  * this returns 0.
1767  */
1768 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1769 {
1770         unsigned long addr;
1771
1772         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1773         if (!regs_within_kernel_stack(regs, addr))
1774                 return 0;
1775         return *(unsigned long *)addr;
1776 }