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