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                 return put_user(child->thread.last_break, (unsigned long __user *)data);
 507         case PTRACE_ENABLE_TE:
 508                 if (!MACHINE_HAS_TE)
 509                         return -EIO;
 510                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 511                 return 0;
 512         case PTRACE_DISABLE_TE:
 513                 if (!MACHINE_HAS_TE)
 514                         return -EIO;
 515                 child->thread.per_flags |= PER_FLAG_NO_TE;
 516                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 517                 return 0;
 518         case PTRACE_TE_ABORT_RAND:
 519                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 520                         return -EIO;
 521                 switch (data) {
 522                 case 0UL:
 523                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 524                         break;
 525                 case 1UL:
 526                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 527                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 528                         break;
 529                 case 2UL:
 530                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 531                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 532                         break;
 533                 default:
 534                         return -EINVAL;
 535                 }
 536                 return 0;
 537         default:
 538                 return ptrace_request(child, request, addr, data);
 539         }
 540 }
 541
 542 #ifdef CONFIG_COMPAT
 543 /*
 544  * Now the fun part starts... a 31 bit program running in the
 545  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 546  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 547  * to handle, the difference to the 64 bit versions of the requests
 548  * is that the access is done in multiples of 4 byte instead of
 549  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 550  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 551  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 552  * is a 31 bit program too, the content of struct user can be
 553  * emulated. A 31 bit program peeking into the struct user of
 554  * a 64 bit program is a no-no.
 555  */
 556
 557 /*
 558  * Same as peek_user_per but for a 31 bit program.
 559  */
 560 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 561                                            addr_t addr)
 562 {
 563         struct compat_per_struct_kernel *dummy32 = NULL;
 564
 565         if (addr == (addr_t) &dummy32->cr9)
 566                 /* Control bits of the active per set. */
 567                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 568                         PER_EVENT_IFETCH : child->thread.per_user.control;
 569         else if (addr == (addr_t) &dummy32->cr10)
 570                 /* Start address of the active per set. */
 571                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 572                         0 : child->thread.per_user.start;
 573         else if (addr == (addr_t) &dummy32->cr11)
 574                 /* End address of the active per set. */
 575                 return test_thread_flag(TIF_SINGLE_STEP) ?
 576                         PSW32_ADDR_INSN : child->thread.per_user.end;
 577         else if (addr == (addr_t) &dummy32->bits)
 578                 /* Single-step bit. */
 579                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 580                         0x80000000 : 0;
 581         else if (addr == (addr_t) &dummy32->starting_addr)
 582                 /* Start address of the user specified per set. */
 583                 return (__u32) child->thread.per_user.start;
 584         else if (addr == (addr_t) &dummy32->ending_addr)
 585                 /* End address of the user specified per set. */
 586                 return (__u32) child->thread.per_user.end;
 587         else if (addr == (addr_t) &dummy32->perc_atmid)
 588                 /* PER code, ATMID and AI of the last PER trap */
 589                 return (__u32) child->thread.per_event.cause << 16;
 590         else if (addr == (addr_t) &dummy32->address)
 591                 /* Address of the last PER trap */
 592                 return (__u32) child->thread.per_event.address;
 593         else if (addr == (addr_t) &dummy32->access_id)
 594                 /* Access id of the last PER trap */
 595                 return (__u32) child->thread.per_event.paid << 24;
 596         return 0;
 597 }
 598
 599 /*
 600  * Same as peek_user but for a 31 bit program.
 601  */
 602 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 603 {
 604         struct compat_user *dummy32 = NULL;
 605         addr_t offset;
 606         __u32 tmp;
 607
 608         if (addr < (addr_t) &dummy32->regs.acrs) {
 609                 struct pt_regs *regs = task_pt_regs(child);
 610                 /*
 611                  * psw and gprs are stored on the stack
 612                  */
 613                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 614                         /* Fake a 31 bit psw mask. */
 615                         tmp = (__u32)(regs->psw.mask >> 32);
 616                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 617                         tmp |= PSW32_USER_BITS;
 618                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 619                         /* Fake a 31 bit psw address. */
 620                         tmp = (__u32) regs->psw.addr |
 621                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 622                 } else {
 623                         /* gpr 0-15 */
 624                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 625                 }
 626         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 627                 /*
 628                  * access registers are stored in the thread structure
 629                  */
 630                 offset = addr - (addr_t) &dummy32->regs.acrs;
 631                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 632
 633         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 634                 /*
 635                  * orig_gpr2 is stored on the kernel stack
 636                  */
 637                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 638
 639         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 640                 /*
 641                  * prevent reads of padding hole between
 642                  * orig_gpr2 and fp_regs on s390.
 643                  */
 644                 tmp = 0;
 645
 646         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 647                 /*
 648                  * floating point control reg. is in the thread structure
 649                  */
 650                 tmp = child->thread.fpu.fpc;
 651
 652         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 653                 /*
 654                  * floating point regs. are either in child->thread.fpu
 655                  * or the child->thread.fpu.vxrs array
 656                  */
 657                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 658                 if (MACHINE_HAS_VX)
 659                         tmp = *(__u32 *)
 660                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 661                 else
 662                         tmp = *(__u32 *)
 663                                ((addr_t) child->thread.fpu.fprs + offset);
 664
 665         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 666                 /*
 667                  * Handle access to the per_info structure.
 668                  */
 669                 addr -= (addr_t) &dummy32->regs.per_info;
 670                 tmp = __peek_user_per_compat(child, addr);
 671
 672         } else
 673                 tmp = 0;
 674
 675         return tmp;
 676 }
 677
 678 static int peek_user_compat(struct task_struct *child,
 679                             addr_t addr, addr_t data)
 680 {
 681         __u32 tmp;
 682
 683         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 684                 return -EIO;
 685
 686         tmp = __peek_user_compat(child, addr);
 687         return put_user(tmp, (__u32 __user *) data);
 688 }
 689
 690 /*
 691  * Same as poke_user_per but for a 31 bit program.
 692  */
 693 static inline void __poke_user_per_compat(struct task_struct *child,
 694                                           addr_t addr, __u32 data)
 695 {
 696         struct compat_per_struct_kernel *dummy32 = NULL;
 697
 698         if (addr == (addr_t) &dummy32->cr9)
 699                 /* PER event mask of the user specified per set. */
 700                 child->thread.per_user.control =
 701                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 702         else if (addr == (addr_t) &dummy32->starting_addr)
 703                 /* Starting address of the user specified per set. */
 704                 child->thread.per_user.start = data;
 705         else if (addr == (addr_t) &dummy32->ending_addr)
 706                 /* Ending address of the user specified per set. */
 707                 child->thread.per_user.end = data;
 708 }
 709
 710 /*
 711  * Same as poke_user but for a 31 bit program.
 712  */
 713 static int __poke_user_compat(struct task_struct *child,
 714                               addr_t addr, addr_t data)
 715 {
 716         struct compat_user *dummy32 = NULL;
 717         __u32 tmp = (__u32) data;
 718         addr_t offset;
 719
 720         if (addr < (addr_t) &dummy32->regs.acrs) {
 721                 struct pt_regs *regs = task_pt_regs(child);
 722                 /*
 723                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 724                  */
 725                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 726                         __u32 mask = PSW32_MASK_USER;
 727
 728                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 729                         /* Build a 64 bit psw mask from 31 bit mask. */
 730                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 731                                 /* Invalid psw mask. */
 732                                 return -EINVAL;
 733                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 734                                 /* Invalid address-space-control bits */
 735                                 return -EINVAL;
 736                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 737                                 (regs->psw.mask & PSW_MASK_BA) |
 738                                 (__u64)(tmp & mask) << 32;
 739                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 740                         /* Build a 64 bit psw address from 31 bit address. */
 741                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 742                         /* Transfer 31 bit amode bit to psw mask. */
 743                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 744                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 745                 } else {
 746
 747                         if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
 748                                 addr == offsetof(struct compat_user, regs.gprs[2]))
 749                                 fixup_int_code(child, data);
 750                         /* gpr 0-15 */
 751                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 752                 }
 753         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 754                 /*
 755                  * access registers are stored in the thread structure
 756                  */
 757                 offset = addr - (addr_t) &dummy32->regs.acrs;
 758                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 759
 760         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 761                 /*
 762                  * orig_gpr2 is stored on the kernel stack
 763                  */
 764                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 765
 766         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 767                 /*
 768                  * prevent writess of padding hole between
 769                  * orig_gpr2 and fp_regs on s390.
 770                  */
 771                 return 0;
 772
 773         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 774                 /*
 775                  * floating point control reg. is in the thread structure
 776                  */
 777                 if (test_fp_ctl(tmp))
 778                         return -EINVAL;
 779                 child->thread.fpu.fpc = data;
 780
 781         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 782                 /*
 783                  * floating point regs. are either in child->thread.fpu
 784                  * or the child->thread.fpu.vxrs array
 785                  */
 786                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 787                 if (MACHINE_HAS_VX)
 788                         *(__u32 *)((addr_t)
 789                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 790                 else
 791                         *(__u32 *)((addr_t)
 792                                 child->thread.fpu.fprs + offset) = tmp;
 793
 794         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 795                 /*
 796                  * Handle access to the per_info structure.
 797                  */
 798                 addr -= (addr_t) &dummy32->regs.per_info;
 799                 __poke_user_per_compat(child, addr, data);
 800         }
 801
 802         return 0;
 803 }
 804
 805 static int poke_user_compat(struct task_struct *child,
 806                             addr_t addr, addr_t data)
 807 {
 808         if (!is_compat_task() || (addr & 3) ||
 809             addr > sizeof(struct compat_user) - 3)
 810                 return -EIO;
 811
 812         return __poke_user_compat(child, addr, data);
 813 }
 814
 815 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 816                         compat_ulong_t caddr, compat_ulong_t cdata)
 817 {
 818         unsigned long addr = caddr;
 819         unsigned long data = cdata;
 820         compat_ptrace_area parea;
 821         int copied, ret;
 822
 823         switch (request) {
 824         case PTRACE_PEEKUSR:
 825                 /* read the word at location addr in the USER area. */
 826                 return peek_user_compat(child, addr, data);
 827
 828         case PTRACE_POKEUSR:
 829                 /* write the word at location addr in the USER area */
 830                 return poke_user_compat(child, addr, data);
 831
 832         case PTRACE_PEEKUSR_AREA:
 833         case PTRACE_POKEUSR_AREA:
 834                 if (copy_from_user(&parea, (void __force __user *) addr,
 835                                                         sizeof(parea)))
 836                         return -EFAULT;
 837                 addr = parea.kernel_addr;
 838                 data = parea.process_addr;
 839                 copied = 0;
 840                 while (copied < parea.len) {
 841                         if (request == PTRACE_PEEKUSR_AREA)
 842                                 ret = peek_user_compat(child, addr, data);
 843                         else {
 844                                 __u32 utmp;
 845                                 if (get_user(utmp,
 846                                              (__u32 __force __user *) data))
 847                                         return -EFAULT;
 848                                 ret = poke_user_compat(child, addr, utmp);
 849                         }
 850                         if (ret)
 851                                 return ret;
 852                         addr += sizeof(unsigned int);
 853                         data += sizeof(unsigned int);
 854                         copied += sizeof(unsigned int);
 855                 }
 856                 return 0;
 857         case PTRACE_GET_LAST_BREAK:
 858                 return put_user(child->thread.last_break, (unsigned int __user *)data);
 859         }
 860         return compat_ptrace_request(child, request, addr, data);
 861 }
 862 #endif
 863
 864 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 865 {
 866         unsigned long mask = -1UL;
 867
 868         /*
 869          * The sysc_tracesys code in entry.S stored the system
 870          * call number to gprs[2].
 871          */
 872         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 873             (tracehook_report_syscall_entry(regs) ||
 874              regs->gprs[2] >= NR_syscalls)) {
 875                 /*
 876                  * Tracing decided this syscall should not happen or the
 877                  * debugger stored an invalid system call number. Skip
 878                  * the system call and the system call restart handling.
 879                  */
 880                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 881                 return -1;
 882         }
 883
 884         /* Do the secure computing check after ptrace. */
 885         if (secure_computing(NULL)) {
 886                 /* seccomp failures shouldn't expose any additional code. */
 887                 return -1;
 888         }
 889
 890         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 891                 trace_sys_enter(regs, regs->gprs[2]);
 892
 893         if (is_compat_task())
 894                 mask = 0xffffffff;
 895
 896         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
 897                             regs->gprs[3] &mask, regs->gprs[4] &mask,
 898                             regs->gprs[5] &mask);
 899
 900         return regs->gprs[2];
 901 }
 902
 903 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 904 {
 905         audit_syscall_exit(regs);
 906
 907         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 908                 trace_sys_exit(regs, regs->gprs[2]);
 909
 910         if (test_thread_flag(TIF_SYSCALL_TRACE))
 911                 tracehook_report_syscall_exit(regs, 0);
 912 }
 913
 914 /*
 915  * user_regset definitions.
 916  */
 917
 918 static int s390_regs_get(struct task_struct *target,
 919                          const struct user_regset *regset,
 920                          unsigned int pos, unsigned int count,
 921                          void *kbuf, void __user *ubuf)
 922 {
 923         if (target == current)
 924                 save_access_regs(target->thread.acrs);
 925
 926         if (kbuf) {
 927                 unsigned long *k = kbuf;
 928                 while (count > 0) {
 929                         *k++ = __peek_user(target, pos);
 930                         count -= sizeof(*k);
 931                         pos += sizeof(*k);
 932                 }
 933         } else {
 934                 unsigned long __user *u = ubuf;
 935                 while (count > 0) {
 936                         if (__put_user(__peek_user(target, pos), u++))
 937                                 return -EFAULT;
 938                         count -= sizeof(*u);
 939                         pos += sizeof(*u);
 940                 }
 941         }
 942         return 0;
 943 }
 944
 945 static int s390_regs_set(struct task_struct *target,
 946                          const struct user_regset *regset,
 947                          unsigned int pos, unsigned int count,
 948                          const void *kbuf, const void __user *ubuf)
 949 {
 950         int rc = 0;
 951
 952         if (target == current)
 953                 save_access_regs(target->thread.acrs);
 954
 955         if (kbuf) {
 956                 const unsigned long *k = kbuf;
 957                 while (count > 0 && !rc) {
 958                         rc = __poke_user(target, pos, *k++);
 959                         count -= sizeof(*k);
 960                         pos += sizeof(*k);
 961                 }
 962         } else {
 963                 const unsigned long  __user *u = ubuf;
 964                 while (count > 0 && !rc) {
 965                         unsigned long word;
 966                         rc = __get_user(word, u++);
 967                         if (rc)
 968                                 break;
 969                         rc = __poke_user(target, pos, word);
 970                         count -= sizeof(*u);
 971                         pos += sizeof(*u);
 972                 }
 973         }
 974
 975         if (rc == 0 && target == current)
 976                 restore_access_regs(target->thread.acrs);
 977
 978         return rc;
 979 }
 980
 981 static int s390_fpregs_get(struct task_struct *target,
 982                            const struct user_regset *regset, unsigned int pos,
 983                            unsigned int count, void *kbuf, void __user *ubuf)
 984 {
 985         _s390_fp_regs fp_regs;
 986
 987         if (target == current)
 988                 save_fpu_regs();
 989
 990         fp_regs.fpc = target->thread.fpu.fpc;
 991         fpregs_store(&fp_regs, &target->thread.fpu);
 992
 993         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 994                                    &fp_regs, 0, -1);
 995 }
 996
 997 static int s390_fpregs_set(struct task_struct *target,
 998                            const struct user_regset *regset, unsigned int pos,
 999                            unsigned int count, const void *kbuf,
1000                            const void __user *ubuf)
1001 {
1002         int rc = 0;
1003         freg_t fprs[__NUM_FPRS];
1004
1005         if (target == current)
1006                 save_fpu_regs();
1007
1008         if (MACHINE_HAS_VX)
1009                 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
1010         else
1011                 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
1012
1013         /* If setting FPC, must validate it first. */
1014         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
1015                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
1016                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
1017                                         0, offsetof(s390_fp_regs, fprs));
1018                 if (rc)
1019                         return rc;
1020                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
1021                         return -EINVAL;
1022                 target->thread.fpu.fpc = ufpc[0];
1023         }
1024
1025         if (rc == 0 && count > 0)
1026                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1027                                         fprs, offsetof(s390_fp_regs, fprs), -1);
1028         if (rc)
1029                 return rc;
1030
1031         if (MACHINE_HAS_VX)
1032                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
1033         else
1034                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
1035
1036         return rc;
1037 }
1038
1039 static int s390_last_break_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         if (count > 0) {
1045                 if (kbuf) {
1046                         unsigned long *k = kbuf;
1047                         *k = target->thread.last_break;
1048                 } else {
1049                         unsigned long  __user *u = ubuf;
1050                         if (__put_user(target->thread.last_break, u))
1051                                 return -EFAULT;
1052                 }
1053         }
1054         return 0;
1055 }
1056
1057 static int s390_last_break_set(struct task_struct *target,
1058                                const struct user_regset *regset,
1059                                unsigned int pos, unsigned int count,
1060                                const void *kbuf, const void __user *ubuf)
1061 {
1062         return 0;
1063 }
1064
1065 static int s390_tdb_get(struct task_struct *target,
1066                         const struct user_regset *regset,
1067                         unsigned int pos, unsigned int count,
1068                         void *kbuf, void __user *ubuf)
1069 {
1070         struct pt_regs *regs = task_pt_regs(target);
1071         unsigned char *data;
1072
1073         if (!(regs->int_code & 0x200))
1074                 return -ENODATA;
1075         data = target->thread.trap_tdb;
1076         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1077 }
1078
1079 static int s390_tdb_set(struct task_struct *target,
1080                         const struct user_regset *regset,
1081                         unsigned int pos, unsigned int count,
1082                         const void *kbuf, const void __user *ubuf)
1083 {
1084         return 0;
1085 }
1086
1087 static int s390_vxrs_low_get(struct task_struct *target,
1088                              const struct user_regset *regset,
1089                              unsigned int pos, unsigned int count,
1090                              void *kbuf, void __user *ubuf)
1091 {
1092         __u64 vxrs[__NUM_VXRS_LOW];
1093         int i;
1094
1095         if (!MACHINE_HAS_VX)
1096                 return -ENODEV;
1097         if (target == current)
1098                 save_fpu_regs();
1099         for (i = 0; i < __NUM_VXRS_LOW; i++)
1100                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1101         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1102 }
1103
1104 static int s390_vxrs_low_set(struct task_struct *target,
1105                              const struct user_regset *regset,
1106                              unsigned int pos, unsigned int count,
1107                              const void *kbuf, const void __user *ubuf)
1108 {
1109         __u64 vxrs[__NUM_VXRS_LOW];
1110         int i, rc;
1111
1112         if (!MACHINE_HAS_VX)
1113                 return -ENODEV;
1114         if (target == current)
1115                 save_fpu_regs();
1116
1117         for (i = 0; i < __NUM_VXRS_LOW; i++)
1118                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1119
1120         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1121         if (rc == 0)
1122                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1123                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1124
1125         return rc;
1126 }
1127
1128 static int s390_vxrs_high_get(struct task_struct *target,
1129                               const struct user_regset *regset,
1130                               unsigned int pos, unsigned int count,
1131                               void *kbuf, void __user *ubuf)
1132 {
1133         __vector128 vxrs[__NUM_VXRS_HIGH];
1134
1135         if (!MACHINE_HAS_VX)
1136                 return -ENODEV;
1137         if (target == current)
1138                 save_fpu_regs();
1139         memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1140
1141         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1142 }
1143
1144 static int s390_vxrs_high_set(struct task_struct *target,
1145                               const struct user_regset *regset,
1146                               unsigned int pos, unsigned int count,
1147                               const void *kbuf, const void __user *ubuf)
1148 {
1149         int rc;
1150
1151         if (!MACHINE_HAS_VX)
1152                 return -ENODEV;
1153         if (target == current)
1154                 save_fpu_regs();
1155
1156         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1157                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1158         return rc;
1159 }
1160
1161 static int s390_system_call_get(struct task_struct *target,
1162                                 const struct user_regset *regset,
1163                                 unsigned int pos, unsigned int count,
1164                                 void *kbuf, void __user *ubuf)
1165 {
1166         unsigned int *data = &target->thread.system_call;
1167         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1168                                    data, 0, sizeof(unsigned int));
1169 }
1170
1171 static int s390_system_call_set(struct task_struct *target,
1172                                 const struct user_regset *regset,
1173                                 unsigned int pos, unsigned int count,
1174                                 const void *kbuf, const void __user *ubuf)
1175 {
1176         unsigned int *data = &target->thread.system_call;
1177         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1178                                   data, 0, sizeof(unsigned int));
1179 }
1180
1181 static int s390_gs_cb_get(struct task_struct *target,
1182                           const struct user_regset *regset,
1183                           unsigned int pos, unsigned int count,
1184                           void *kbuf, void __user *ubuf)
1185 {
1186         struct gs_cb *data = target->thread.gs_cb;
1187
1188         if (!MACHINE_HAS_GS)
1189                 return -ENODEV;
1190         if (!data)
1191                 return -ENODATA;
1192         if (target == current)
1193                 save_gs_cb(data);
1194         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1195                                    data, 0, sizeof(struct gs_cb));
1196 }
1197
1198 static int s390_gs_cb_set(struct task_struct *target,
1199                           const struct user_regset *regset,
1200                           unsigned int pos, unsigned int count,
1201                           const void *kbuf, const void __user *ubuf)
1202 {
1203         struct gs_cb gs_cb = { }, *data = NULL;
1204         int rc;
1205
1206         if (!MACHINE_HAS_GS)
1207                 return -ENODEV;
1208         if (!target->thread.gs_cb) {
1209                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1210                 if (!data)
1211                         return -ENOMEM;
1212         }
1213         if (!target->thread.gs_cb)
1214                 gs_cb.gsd = 25;
1215         else if (target == current)
1216                 save_gs_cb(&gs_cb);
1217         else
1218                 gs_cb = *target->thread.gs_cb;
1219         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1220                                 &gs_cb, 0, sizeof(gs_cb));
1221         if (rc) {
1222                 kfree(data);
1223                 return -EFAULT;
1224         }
1225         preempt_disable();
1226         if (!target->thread.gs_cb)
1227                 target->thread.gs_cb = data;
1228         *target->thread.gs_cb = gs_cb;
1229         if (target == current) {
1230                 __ctl_set_bit(2, 4);
1231                 restore_gs_cb(target->thread.gs_cb);
1232         }
1233         preempt_enable();
1234         return rc;
1235 }
1236
1237 static int s390_gs_bc_get(struct task_struct *target,
1238                           const struct user_regset *regset,
1239                           unsigned int pos, unsigned int count,
1240                           void *kbuf, void __user *ubuf)
1241 {
1242         struct gs_cb *data = target->thread.gs_bc_cb;
1243
1244         if (!MACHINE_HAS_GS)
1245                 return -ENODEV;
1246         if (!data)
1247                 return -ENODATA;
1248         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1249                                    data, 0, sizeof(struct gs_cb));
1250 }
1251
1252 static int s390_gs_bc_set(struct task_struct *target,
1253                           const struct user_regset *regset,
1254                           unsigned int pos, unsigned int count,
1255                           const void *kbuf, const void __user *ubuf)
1256 {
1257         struct gs_cb *data = target->thread.gs_bc_cb;
1258
1259         if (!MACHINE_HAS_GS)
1260                 return -ENODEV;
1261         if (!data) {
1262                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1263                 if (!data)
1264                         return -ENOMEM;
1265                 target->thread.gs_bc_cb = data;
1266         }
1267         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1268                                   data, 0, sizeof(struct gs_cb));
1269 }
1270
1271 static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1272 {
1273         return (cb->rca & 0x1f) == 0 &&
1274                 (cb->roa & 0xfff) == 0 &&
1275                 (cb->rla & 0xfff) == 0xfff &&
1276                 cb->s == 1 &&
1277                 cb->k == 1 &&
1278                 cb->h == 0 &&
1279                 cb->reserved1 == 0 &&
1280                 cb->ps == 1 &&
1281                 cb->qs == 0 &&
1282                 cb->pc == 1 &&
1283                 cb->qc == 0 &&
1284                 cb->reserved2 == 0 &&
1285                 cb->reserved3 == 0 &&
1286                 cb->reserved4 == 0 &&
1287                 cb->reserved5 == 0 &&
1288                 cb->reserved6 == 0 &&
1289                 cb->reserved7 == 0 &&
1290                 cb->reserved8 == 0 &&
1291                 cb->rla >= cb->roa &&
1292                 cb->rca >= cb->roa &&
1293                 cb->rca <= cb->rla+1 &&
1294                 cb->m < 3;
1295 }
1296
1297 static int s390_runtime_instr_get(struct task_struct *target,
1298                                 const struct user_regset *regset,
1299                                 unsigned int pos, unsigned int count,
1300                                 void *kbuf, void __user *ubuf)
1301 {
1302         struct runtime_instr_cb *data = target->thread.ri_cb;
1303
1304         if (!test_facility(64))
1305                 return -ENODEV;
1306         if (!data)
1307                 return -ENODATA;
1308
1309         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1310                                    data, 0, sizeof(struct runtime_instr_cb));
1311 }
1312
1313 static int s390_runtime_instr_set(struct task_struct *target,
1314                                   const struct user_regset *regset,
1315                                   unsigned int pos, unsigned int count,
1316                                   const void *kbuf, const void __user *ubuf)
1317 {
1318         struct runtime_instr_cb ri_cb = { }, *data = NULL;
1319         int rc;
1320
1321         if (!test_facility(64))
1322                 return -ENODEV;
1323
1324         if (!target->thread.ri_cb) {
1325                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1326                 if (!data)
1327                         return -ENOMEM;
1328         }
1329
1330         if (target->thread.ri_cb) {
1331                 if (target == current)
1332                         store_runtime_instr_cb(&ri_cb);
1333                 else
1334                         ri_cb = *target->thread.ri_cb;
1335         }
1336
1337         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1338                                 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1339         if (rc) {
1340                 kfree(data);
1341                 return -EFAULT;
1342         }
1343
1344         if (!is_ri_cb_valid(&ri_cb)) {
1345                 kfree(data);
1346                 return -EINVAL;
1347         }
1348         /*
1349          * Override access key in any case, since user space should
1350          * not be able to set it, nor should it care about it.
1351          */
1352         ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1353         preempt_disable();
1354         if (!target->thread.ri_cb)
1355                 target->thread.ri_cb = data;
1356         *target->thread.ri_cb = ri_cb;
1357         if (target == current)
1358                 load_runtime_instr_cb(target->thread.ri_cb);
1359         preempt_enable();
1360
1361         return 0;
1362 }
1363
1364 static const struct user_regset s390_regsets[] = {
1365         {
1366                 .core_note_type = NT_PRSTATUS,
1367                 .n = sizeof(s390_regs) / sizeof(long),
1368                 .size = sizeof(long),
1369                 .align = sizeof(long),
1370                 .get = s390_regs_get,
1371                 .set = s390_regs_set,
1372         },
1373         {
1374                 .core_note_type = NT_PRFPREG,
1375                 .n = sizeof(s390_fp_regs) / sizeof(long),
1376                 .size = sizeof(long),
1377                 .align = sizeof(long),
1378                 .get = s390_fpregs_get,
1379                 .set = s390_fpregs_set,
1380         },
1381         {
1382                 .core_note_type = NT_S390_SYSTEM_CALL,
1383                 .n = 1,
1384                 .size = sizeof(unsigned int),
1385                 .align = sizeof(unsigned int),
1386                 .get = s390_system_call_get,
1387                 .set = s390_system_call_set,
1388         },
1389         {
1390                 .core_note_type = NT_S390_LAST_BREAK,
1391                 .n = 1,
1392                 .size = sizeof(long),
1393                 .align = sizeof(long),
1394                 .get = s390_last_break_get,
1395                 .set = s390_last_break_set,
1396         },
1397         {
1398                 .core_note_type = NT_S390_TDB,
1399                 .n = 1,
1400                 .size = 256,
1401                 .align = 1,
1402                 .get = s390_tdb_get,
1403                 .set = s390_tdb_set,
1404         },
1405         {
1406                 .core_note_type = NT_S390_VXRS_LOW,
1407                 .n = __NUM_VXRS_LOW,
1408                 .size = sizeof(__u64),
1409                 .align = sizeof(__u64),
1410                 .get = s390_vxrs_low_get,
1411                 .set = s390_vxrs_low_set,
1412         },
1413         {
1414                 .core_note_type = NT_S390_VXRS_HIGH,
1415                 .n = __NUM_VXRS_HIGH,
1416                 .size = sizeof(__vector128),
1417                 .align = sizeof(__vector128),
1418                 .get = s390_vxrs_high_get,
1419                 .set = s390_vxrs_high_set,
1420         },
1421         {
1422                 .core_note_type = NT_S390_GS_CB,
1423                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1424                 .size = sizeof(__u64),
1425                 .align = sizeof(__u64),
1426                 .get = s390_gs_cb_get,
1427                 .set = s390_gs_cb_set,
1428         },
1429         {
1430                 .core_note_type = NT_S390_GS_BC,
1431                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1432                 .size = sizeof(__u64),
1433                 .align = sizeof(__u64),
1434                 .get = s390_gs_bc_get,
1435                 .set = s390_gs_bc_set,
1436         },
1437         {
1438                 .core_note_type = NT_S390_RI_CB,
1439                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1440                 .size = sizeof(__u64),
1441                 .align = sizeof(__u64),
1442                 .get = s390_runtime_instr_get,
1443                 .set = s390_runtime_instr_set,
1444         },
1445 };
1446
1447 static const struct user_regset_view user_s390_view = {
1448         .name = UTS_MACHINE,
1449         .e_machine = EM_S390,
1450         .regsets = s390_regsets,
1451         .n = ARRAY_SIZE(s390_regsets)
1452 };
1453
1454 #ifdef CONFIG_COMPAT
1455 static int s390_compat_regs_get(struct task_struct *target,
1456                                 const struct user_regset *regset,
1457                                 unsigned int pos, unsigned int count,
1458                                 void *kbuf, void __user *ubuf)
1459 {
1460         if (target == current)
1461                 save_access_regs(target->thread.acrs);
1462
1463         if (kbuf) {
1464                 compat_ulong_t *k = kbuf;
1465                 while (count > 0) {
1466                         *k++ = __peek_user_compat(target, pos);
1467                         count -= sizeof(*k);
1468                         pos += sizeof(*k);
1469                 }
1470         } else {
1471                 compat_ulong_t __user *u = ubuf;
1472                 while (count > 0) {
1473                         if (__put_user(__peek_user_compat(target, pos), u++))
1474                                 return -EFAULT;
1475                         count -= sizeof(*u);
1476                         pos += sizeof(*u);
1477                 }
1478         }
1479         return 0;
1480 }
1481
1482 static int s390_compat_regs_set(struct task_struct *target,
1483                                 const struct user_regset *regset,
1484                                 unsigned int pos, unsigned int count,
1485                                 const void *kbuf, const void __user *ubuf)
1486 {
1487         int rc = 0;
1488
1489         if (target == current)
1490                 save_access_regs(target->thread.acrs);
1491
1492         if (kbuf) {
1493                 const compat_ulong_t *k = kbuf;
1494                 while (count > 0 && !rc) {
1495                         rc = __poke_user_compat(target, pos, *k++);
1496                         count -= sizeof(*k);
1497                         pos += sizeof(*k);
1498                 }
1499         } else {
1500                 const compat_ulong_t  __user *u = ubuf;
1501                 while (count > 0 && !rc) {
1502                         compat_ulong_t word;
1503                         rc = __get_user(word, u++);
1504                         if (rc)
1505                                 break;
1506                         rc = __poke_user_compat(target, pos, word);
1507                         count -= sizeof(*u);
1508                         pos += sizeof(*u);
1509                 }
1510         }
1511
1512         if (rc == 0 && target == current)
1513                 restore_access_regs(target->thread.acrs);
1514
1515         return rc;
1516 }
1517
1518 static int s390_compat_regs_high_get(struct task_struct *target,
1519                                      const struct user_regset *regset,
1520                                      unsigned int pos, unsigned int count,
1521                                      void *kbuf, void __user *ubuf)
1522 {
1523         compat_ulong_t *gprs_high;
1524
1525         gprs_high = (compat_ulong_t *)
1526                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1527         if (kbuf) {
1528                 compat_ulong_t *k = kbuf;
1529                 while (count > 0) {
1530                         *k++ = *gprs_high;
1531                         gprs_high += 2;
1532                         count -= sizeof(*k);
1533                 }
1534         } else {
1535                 compat_ulong_t __user *u = ubuf;
1536                 while (count > 0) {
1537                         if (__put_user(*gprs_high, u++))
1538                                 return -EFAULT;
1539                         gprs_high += 2;
1540                         count -= sizeof(*u);
1541                 }
1542         }
1543         return 0;
1544 }
1545
1546 static int s390_compat_regs_high_set(struct task_struct *target,
1547                                      const struct user_regset *regset,
1548                                      unsigned int pos, unsigned int count,
1549                                      const void *kbuf, const void __user *ubuf)
1550 {
1551         compat_ulong_t *gprs_high;
1552         int rc = 0;
1553
1554         gprs_high = (compat_ulong_t *)
1555                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1556         if (kbuf) {
1557                 const compat_ulong_t *k = kbuf;
1558                 while (count > 0) {
1559                         *gprs_high = *k++;
1560                         *gprs_high += 2;
1561                         count -= sizeof(*k);
1562                 }
1563         } else {
1564                 const compat_ulong_t  __user *u = ubuf;
1565                 while (count > 0 && !rc) {
1566                         unsigned long word;
1567                         rc = __get_user(word, u++);
1568                         if (rc)
1569                                 break;
1570                         *gprs_high = word;
1571                         *gprs_high += 2;
1572                         count -= sizeof(*u);
1573                 }
1574         }
1575
1576         return rc;
1577 }
1578
1579 static int s390_compat_last_break_get(struct task_struct *target,
1580                                       const struct user_regset *regset,
1581                                       unsigned int pos, unsigned int count,
1582                                       void *kbuf, void __user *ubuf)
1583 {
1584         compat_ulong_t last_break;
1585
1586         if (count > 0) {
1587                 last_break = target->thread.last_break;
1588                 if (kbuf) {
1589                         unsigned long *k = kbuf;
1590                         *k = last_break;
1591                 } else {
1592                         unsigned long  __user *u = ubuf;
1593                         if (__put_user(last_break, u))
1594                                 return -EFAULT;
1595                 }
1596         }
1597         return 0;
1598 }
1599
1600 static int s390_compat_last_break_set(struct task_struct *target,
1601                                       const struct user_regset *regset,
1602                                       unsigned int pos, unsigned int count,
1603                                       const void *kbuf, const void __user *ubuf)
1604 {
1605         return 0;
1606 }
1607
1608 static const struct user_regset s390_compat_regsets[] = {
1609         {
1610                 .core_note_type = NT_PRSTATUS,
1611                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1612                 .size = sizeof(compat_long_t),
1613                 .align = sizeof(compat_long_t),
1614                 .get = s390_compat_regs_get,
1615                 .set = s390_compat_regs_set,
1616         },
1617         {
1618                 .core_note_type = NT_PRFPREG,
1619                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1620                 .size = sizeof(compat_long_t),
1621                 .align = sizeof(compat_long_t),
1622                 .get = s390_fpregs_get,
1623                 .set = s390_fpregs_set,
1624         },
1625         {
1626                 .core_note_type = NT_S390_SYSTEM_CALL,
1627                 .n = 1,
1628                 .size = sizeof(compat_uint_t),
1629                 .align = sizeof(compat_uint_t),
1630                 .get = s390_system_call_get,
1631                 .set = s390_system_call_set,
1632         },
1633         {
1634                 .core_note_type = NT_S390_LAST_BREAK,
1635                 .n = 1,
1636                 .size = sizeof(long),
1637                 .align = sizeof(long),
1638                 .get = s390_compat_last_break_get,
1639                 .set = s390_compat_last_break_set,
1640         },
1641         {
1642                 .core_note_type = NT_S390_TDB,
1643                 .n = 1,
1644                 .size = 256,
1645                 .align = 1,
1646                 .get = s390_tdb_get,
1647                 .set = s390_tdb_set,
1648         },
1649         {
1650                 .core_note_type = NT_S390_VXRS_LOW,
1651                 .n = __NUM_VXRS_LOW,
1652                 .size = sizeof(__u64),
1653                 .align = sizeof(__u64),
1654                 .get = s390_vxrs_low_get,
1655                 .set = s390_vxrs_low_set,
1656         },
1657         {
1658                 .core_note_type = NT_S390_VXRS_HIGH,
1659                 .n = __NUM_VXRS_HIGH,
1660                 .size = sizeof(__vector128),
1661                 .align = sizeof(__vector128),
1662                 .get = s390_vxrs_high_get,
1663                 .set = s390_vxrs_high_set,
1664         },
1665         {
1666                 .core_note_type = NT_S390_HIGH_GPRS,
1667                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1668                 .size = sizeof(compat_long_t),
1669                 .align = sizeof(compat_long_t),
1670                 .get = s390_compat_regs_high_get,
1671                 .set = s390_compat_regs_high_set,
1672         },
1673         {
1674                 .core_note_type = NT_S390_GS_CB,
1675                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1676                 .size = sizeof(__u64),
1677                 .align = sizeof(__u64),
1678                 .get = s390_gs_cb_get,
1679                 .set = s390_gs_cb_set,
1680         },
1681         {
1682                 .core_note_type = NT_S390_GS_BC,
1683                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1684                 .size = sizeof(__u64),
1685                 .align = sizeof(__u64),
1686                 .get = s390_gs_bc_get,
1687                 .set = s390_gs_bc_set,
1688         },
1689         {
1690                 .core_note_type = NT_S390_RI_CB,
1691                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1692                 .size = sizeof(__u64),
1693                 .align = sizeof(__u64),
1694                 .get = s390_runtime_instr_get,
1695                 .set = s390_runtime_instr_set,
1696         },
1697 };
1698
1699 static const struct user_regset_view user_s390_compat_view = {
1700         .name = "s390",
1701         .e_machine = EM_S390,
1702         .regsets = s390_compat_regsets,
1703         .n = ARRAY_SIZE(s390_compat_regsets)
1704 };
1705 #endif
1706
1707 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1708 {
1709 #ifdef CONFIG_COMPAT
1710         if (test_tsk_thread_flag(task, TIF_31BIT))
1711                 return &user_s390_compat_view;
1712 #endif
1713         return &user_s390_view;
1714 }
1715
1716 static const char *gpr_names[NUM_GPRS] = {
1717         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1718         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1719 };
1720
1721 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1722 {
1723         if (offset >= NUM_GPRS)
1724                 return 0;
1725         return regs->gprs[offset];
1726 }
1727
1728 int regs_query_register_offset(const char *name)
1729 {
1730         unsigned long offset;
1731
1732         if (!name || *name != 'r')
1733                 return -EINVAL;
1734         if (kstrtoul(name + 1, 10, &offset))
1735                 return -EINVAL;
1736         if (offset >= NUM_GPRS)
1737                 return -EINVAL;
1738         return offset;
1739 }
1740
1741 const char *regs_query_register_name(unsigned int offset)
1742 {
1743         if (offset >= NUM_GPRS)
1744                 return NULL;
1745         return gpr_names[offset];
1746 }
1747
1748 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1749 {
1750         unsigned long ksp = kernel_stack_pointer(regs);
1751
1752         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1753 }
1754
1755 /**
1756  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1757  * @regs:pt_regs which contains kernel stack pointer.
1758  * @n:stack entry number.
1759  *
1760  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1761  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1762  * this returns 0.
1763  */
1764 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1765 {
1766         unsigned long addr;
1767
1768         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1769         if (!regs_within_kernel_stack(regs, addr))
1770                 return 0;
1771         return *(unsigned long *)addr;
1772 }