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 /*
 329  * Write a word to the user area of a process at location addr. This
 330  * operation does have an additional problem compared to peek_user.
 331  * Stores to the program status word and on the floating point
 332  * control register needs to get checked for validity.
 333  */
 334 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 335 {
 336         struct user *dummy = NULL;
 337         addr_t offset;
 338
 339         if (addr < (addr_t) &dummy->regs.acrs) {
 340                 /*
 341                  * psw and gprs are stored on the stack
 342                  */
 343                 if (addr == (addr_t) &dummy->regs.psw.mask) {
 344                         unsigned long mask = PSW_MASK_USER;
 345
 346                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 347                         if ((data ^ PSW_USER_BITS) & ~mask)
 348                                 /* Invalid psw mask. */
 349                                 return -EINVAL;
 350                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 351                                 /* Invalid address-space-control bits */
 352                                 return -EINVAL;
 353                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 354                                 /* Invalid addressing mode bits */
 355                                 return -EINVAL;
 356                 }
 357                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 358
 359         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 360                 /*
 361                  * access registers are stored in the thread structure
 362                  */
 363                 offset = addr - (addr_t) &dummy->regs.acrs;
 364                 /*
 365                  * Very special case: old & broken 64 bit gdb writing
 366                  * to acrs[15] with a 64 bit value. Ignore the lower
 367                  * half of the value and write the upper 32 bit to
 368                  * acrs[15]. Sick...
 369                  */
 370                 if (addr == (addr_t) &dummy->regs.acrs[15])
 371                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 372                 else
 373                         *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 374
 375         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 376                 /*
 377                  * orig_gpr2 is stored on the kernel stack
 378                  */
 379                 task_pt_regs(child)->orig_gpr2 = data;
 380
 381         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 382                 /*
 383                  * prevent writes of padding hole between
 384                  * orig_gpr2 and fp_regs on s390.
 385                  */
 386                 return 0;
 387
 388         } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
 389                 /*
 390                  * floating point control reg. is in the thread structure
 391                  */
 392                 if ((unsigned int) data != 0 ||
 393                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 394                         return -EINVAL;
 395                 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
 396
 397         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 398                 /*
 399                  * floating point regs. are either in child->thread.fpu
 400                  * or the child->thread.fpu.vxrs array
 401                  */
 402                 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
 403                 if (MACHINE_HAS_VX)
 404                         *(addr_t *)((addr_t)
 405                                 child->thread.fpu.vxrs + 2*offset) = data;
 406                 else
 407                         *(addr_t *)((addr_t)
 408                                 child->thread.fpu.fprs + offset) = data;
 409
 410         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 411                 /*
 412                  * Handle access to the per_info structure.
 413                  */
 414                 addr -= (addr_t) &dummy->regs.per_info;
 415                 __poke_user_per(child, addr, data);
 416
 417         }
 418
 419         return 0;
 420 }
 421
 422 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 423 {
 424         addr_t mask;
 425
 426         /*
 427          * Stupid gdb peeks/pokes the access registers in 64 bit with
 428          * an alignment of 4. Programmers from hell indeed...
 429          */
 430         mask = __ADDR_MASK;
 431         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 432             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 433                 mask = 3;
 434         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 435                 return -EIO;
 436
 437         return __poke_user(child, addr, data);
 438 }
 439
 440 long arch_ptrace(struct task_struct *child, long request,
 441                  unsigned long addr, unsigned long data)
 442 {
 443         ptrace_area parea;
 444         int copied, ret;
 445
 446         switch (request) {
 447         case PTRACE_PEEKUSR:
 448                 /* read the word at location addr in the USER area. */
 449                 return peek_user(child, addr, data);
 450
 451         case PTRACE_POKEUSR:
 452                 /* write the word at location addr in the USER area */
 453                 return poke_user(child, addr, data);
 454
 455         case PTRACE_PEEKUSR_AREA:
 456         case PTRACE_POKEUSR_AREA:
 457                 if (copy_from_user(&parea, (void __force __user *) addr,
 458                                                         sizeof(parea)))
 459                         return -EFAULT;
 460                 addr = parea.kernel_addr;
 461                 data = parea.process_addr;
 462                 copied = 0;
 463                 while (copied < parea.len) {
 464                         if (request == PTRACE_PEEKUSR_AREA)
 465                                 ret = peek_user(child, addr, data);
 466                         else {
 467                                 addr_t utmp;
 468                                 if (get_user(utmp,
 469                                              (addr_t __force __user *) data))
 470                                         return -EFAULT;
 471                                 ret = poke_user(child, addr, utmp);
 472                         }
 473                         if (ret)
 474                                 return ret;
 475                         addr += sizeof(unsigned long);
 476                         data += sizeof(unsigned long);
 477                         copied += sizeof(unsigned long);
 478                 }
 479                 return 0;
 480         case PTRACE_GET_LAST_BREAK:
 481                 put_user(child->thread.last_break,
 482                          (unsigned long __user *) data);
 483                 return 0;
 484         case PTRACE_ENABLE_TE:
 485                 if (!MACHINE_HAS_TE)
 486                         return -EIO;
 487                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 488                 return 0;
 489         case PTRACE_DISABLE_TE:
 490                 if (!MACHINE_HAS_TE)
 491                         return -EIO;
 492                 child->thread.per_flags |= PER_FLAG_NO_TE;
 493                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 494                 return 0;
 495         case PTRACE_TE_ABORT_RAND:
 496                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 497                         return -EIO;
 498                 switch (data) {
 499                 case 0UL:
 500                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 501                         break;
 502                 case 1UL:
 503                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 504                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 505                         break;
 506                 case 2UL:
 507                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 508                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 509                         break;
 510                 default:
 511                         return -EINVAL;
 512                 }
 513                 return 0;
 514         default:
 515                 return ptrace_request(child, request, addr, data);
 516         }
 517 }
 518
 519 #ifdef CONFIG_COMPAT
 520 /*
 521  * Now the fun part starts... a 31 bit program running in the
 522  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 523  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 524  * to handle, the difference to the 64 bit versions of the requests
 525  * is that the access is done in multiples of 4 byte instead of
 526  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 527  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 528  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 529  * is a 31 bit program too, the content of struct user can be
 530  * emulated. A 31 bit program peeking into the struct user of
 531  * a 64 bit program is a no-no.
 532  */
 533
 534 /*
 535  * Same as peek_user_per but for a 31 bit program.
 536  */
 537 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 538                                            addr_t addr)
 539 {
 540         struct compat_per_struct_kernel *dummy32 = NULL;
 541
 542         if (addr == (addr_t) &dummy32->cr9)
 543                 /* Control bits of the active per set. */
 544                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 545                         PER_EVENT_IFETCH : child->thread.per_user.control;
 546         else if (addr == (addr_t) &dummy32->cr10)
 547                 /* Start address of the active per set. */
 548                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 549                         0 : child->thread.per_user.start;
 550         else if (addr == (addr_t) &dummy32->cr11)
 551                 /* End address of the active per set. */
 552                 return test_thread_flag(TIF_SINGLE_STEP) ?
 553                         PSW32_ADDR_INSN : child->thread.per_user.end;
 554         else if (addr == (addr_t) &dummy32->bits)
 555                 /* Single-step bit. */
 556                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 557                         0x80000000 : 0;
 558         else if (addr == (addr_t) &dummy32->starting_addr)
 559                 /* Start address of the user specified per set. */
 560                 return (__u32) child->thread.per_user.start;
 561         else if (addr == (addr_t) &dummy32->ending_addr)
 562                 /* End address of the user specified per set. */
 563                 return (__u32) child->thread.per_user.end;
 564         else if (addr == (addr_t) &dummy32->perc_atmid)
 565                 /* PER code, ATMID and AI of the last PER trap */
 566                 return (__u32) child->thread.per_event.cause << 16;
 567         else if (addr == (addr_t) &dummy32->address)
 568                 /* Address of the last PER trap */
 569                 return (__u32) child->thread.per_event.address;
 570         else if (addr == (addr_t) &dummy32->access_id)
 571                 /* Access id of the last PER trap */
 572                 return (__u32) child->thread.per_event.paid << 24;
 573         return 0;
 574 }
 575
 576 /*
 577  * Same as peek_user but for a 31 bit program.
 578  */
 579 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 580 {
 581         struct compat_user *dummy32 = NULL;
 582         addr_t offset;
 583         __u32 tmp;
 584
 585         if (addr < (addr_t) &dummy32->regs.acrs) {
 586                 struct pt_regs *regs = task_pt_regs(child);
 587                 /*
 588                  * psw and gprs are stored on the stack
 589                  */
 590                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 591                         /* Fake a 31 bit psw mask. */
 592                         tmp = (__u32)(regs->psw.mask >> 32);
 593                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 594                         tmp |= PSW32_USER_BITS;
 595                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 596                         /* Fake a 31 bit psw address. */
 597                         tmp = (__u32) regs->psw.addr |
 598                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 599                 } else {
 600                         /* gpr 0-15 */
 601                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 602                 }
 603         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 604                 /*
 605                  * access registers are stored in the thread structure
 606                  */
 607                 offset = addr - (addr_t) &dummy32->regs.acrs;
 608                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 609
 610         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 611                 /*
 612                  * orig_gpr2 is stored on the kernel stack
 613                  */
 614                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 615
 616         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 617                 /*
 618                  * prevent reads of padding hole between
 619                  * orig_gpr2 and fp_regs on s390.
 620                  */
 621                 tmp = 0;
 622
 623         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 624                 /*
 625                  * floating point control reg. is in the thread structure
 626                  */
 627                 tmp = child->thread.fpu.fpc;
 628
 629         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 630                 /*
 631                  * floating point regs. are either in child->thread.fpu
 632                  * or the child->thread.fpu.vxrs array
 633                  */
 634                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 635                 if (MACHINE_HAS_VX)
 636                         tmp = *(__u32 *)
 637                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 638                 else
 639                         tmp = *(__u32 *)
 640                                ((addr_t) child->thread.fpu.fprs + offset);
 641
 642         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 643                 /*
 644                  * Handle access to the per_info structure.
 645                  */
 646                 addr -= (addr_t) &dummy32->regs.per_info;
 647                 tmp = __peek_user_per_compat(child, addr);
 648
 649         } else
 650                 tmp = 0;
 651
 652         return tmp;
 653 }
 654
 655 static int peek_user_compat(struct task_struct *child,
 656                             addr_t addr, addr_t data)
 657 {
 658         __u32 tmp;
 659
 660         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 661                 return -EIO;
 662
 663         tmp = __peek_user_compat(child, addr);
 664         return put_user(tmp, (__u32 __user *) data);
 665 }
 666
 667 /*
 668  * Same as poke_user_per but for a 31 bit program.
 669  */
 670 static inline void __poke_user_per_compat(struct task_struct *child,
 671                                           addr_t addr, __u32 data)
 672 {
 673         struct compat_per_struct_kernel *dummy32 = NULL;
 674
 675         if (addr == (addr_t) &dummy32->cr9)
 676                 /* PER event mask of the user specified per set. */
 677                 child->thread.per_user.control =
 678                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 679         else if (addr == (addr_t) &dummy32->starting_addr)
 680                 /* Starting address of the user specified per set. */
 681                 child->thread.per_user.start = data;
 682         else if (addr == (addr_t) &dummy32->ending_addr)
 683                 /* Ending address of the user specified per set. */
 684                 child->thread.per_user.end = data;
 685 }
 686
 687 /*
 688  * Same as poke_user but for a 31 bit program.
 689  */
 690 static int __poke_user_compat(struct task_struct *child,
 691                               addr_t addr, addr_t data)
 692 {
 693         struct compat_user *dummy32 = NULL;
 694         __u32 tmp = (__u32) data;
 695         addr_t offset;
 696
 697         if (addr < (addr_t) &dummy32->regs.acrs) {
 698                 struct pt_regs *regs = task_pt_regs(child);
 699                 /*
 700                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 701                  */
 702                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 703                         __u32 mask = PSW32_MASK_USER;
 704
 705                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 706                         /* Build a 64 bit psw mask from 31 bit mask. */
 707                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 708                                 /* Invalid psw mask. */
 709                                 return -EINVAL;
 710                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 711                                 /* Invalid address-space-control bits */
 712                                 return -EINVAL;
 713                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 714                                 (regs->psw.mask & PSW_MASK_BA) |
 715                                 (__u64)(tmp & mask) << 32;
 716                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 717                         /* Build a 64 bit psw address from 31 bit address. */
 718                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 719                         /* Transfer 31 bit amode bit to psw mask. */
 720                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 721                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 722                 } else {
 723                         /* gpr 0-15 */
 724                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 725                 }
 726         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 727                 /*
 728                  * access registers are stored in the thread structure
 729                  */
 730                 offset = addr - (addr_t) &dummy32->regs.acrs;
 731                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 732
 733         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 734                 /*
 735                  * orig_gpr2 is stored on the kernel stack
 736                  */
 737                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 738
 739         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 740                 /*
 741                  * prevent writess of padding hole between
 742                  * orig_gpr2 and fp_regs on s390.
 743                  */
 744                 return 0;
 745
 746         } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
 747                 /*
 748                  * floating point control reg. is in the thread structure
 749                  */
 750                 if (test_fp_ctl(tmp))
 751                         return -EINVAL;
 752                 child->thread.fpu.fpc = data;
 753
 754         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 755                 /*
 756                  * floating point regs. are either in child->thread.fpu
 757                  * or the child->thread.fpu.vxrs array
 758                  */
 759                 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
 760                 if (MACHINE_HAS_VX)
 761                         *(__u32 *)((addr_t)
 762                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 763                 else
 764                         *(__u32 *)((addr_t)
 765                                 child->thread.fpu.fprs + offset) = tmp;
 766
 767         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 768                 /*
 769                  * Handle access to the per_info structure.
 770                  */
 771                 addr -= (addr_t) &dummy32->regs.per_info;
 772                 __poke_user_per_compat(child, addr, data);
 773         }
 774
 775         return 0;
 776 }
 777
 778 static int poke_user_compat(struct task_struct *child,
 779                             addr_t addr, addr_t data)
 780 {
 781         if (!is_compat_task() || (addr & 3) ||
 782             addr > sizeof(struct compat_user) - 3)
 783                 return -EIO;
 784
 785         return __poke_user_compat(child, addr, data);
 786 }
 787
 788 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 789                         compat_ulong_t caddr, compat_ulong_t cdata)
 790 {
 791         unsigned long addr = caddr;
 792         unsigned long data = cdata;
 793         compat_ptrace_area parea;
 794         int copied, ret;
 795
 796         switch (request) {
 797         case PTRACE_PEEKUSR:
 798                 /* read the word at location addr in the USER area. */
 799                 return peek_user_compat(child, addr, data);
 800
 801         case PTRACE_POKEUSR:
 802                 /* write the word at location addr in the USER area */
 803                 return poke_user_compat(child, addr, data);
 804
 805         case PTRACE_PEEKUSR_AREA:
 806         case PTRACE_POKEUSR_AREA:
 807                 if (copy_from_user(&parea, (void __force __user *) addr,
 808                                                         sizeof(parea)))
 809                         return -EFAULT;
 810                 addr = parea.kernel_addr;
 811                 data = parea.process_addr;
 812                 copied = 0;
 813                 while (copied < parea.len) {
 814                         if (request == PTRACE_PEEKUSR_AREA)
 815                                 ret = peek_user_compat(child, addr, data);
 816                         else {
 817                                 __u32 utmp;
 818                                 if (get_user(utmp,
 819                                              (__u32 __force __user *) data))
 820                                         return -EFAULT;
 821                                 ret = poke_user_compat(child, addr, utmp);
 822                         }
 823                         if (ret)
 824                                 return ret;
 825                         addr += sizeof(unsigned int);
 826                         data += sizeof(unsigned int);
 827                         copied += sizeof(unsigned int);
 828                 }
 829                 return 0;
 830         case PTRACE_GET_LAST_BREAK:
 831                 put_user(child->thread.last_break,
 832                          (unsigned int __user *) data);
 833                 return 0;
 834         }
 835         return compat_ptrace_request(child, request, addr, data);
 836 }
 837 #endif
 838
 839 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 840 {
 841         unsigned long mask = -1UL;
 842
 843         /*
 844          * The sysc_tracesys code in entry.S stored the system
 845          * call number to gprs[2].
 846          */
 847         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 848             (tracehook_report_syscall_entry(regs) ||
 849              regs->gprs[2] >= NR_syscalls)) {
 850                 /*
 851                  * Tracing decided this syscall should not happen or the
 852                  * debugger stored an invalid system call number. Skip
 853                  * the system call and the system call restart handling.
 854                  */
 855                 clear_pt_regs_flag(regs, PIF_SYSCALL);
 856                 return -1;
 857         }
 858
 859         /* Do the secure computing check after ptrace. */
 860         if (secure_computing(NULL)) {
 861                 /* seccomp failures shouldn't expose any additional code. */
 862                 return -1;
 863         }
 864
 865         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 866                 trace_sys_enter(regs, regs->gprs[2]);
 867
 868         if (is_compat_task())
 869                 mask = 0xffffffff;
 870
 871         audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
 872                             regs->gprs[3] &mask, regs->gprs[4] &mask,
 873                             regs->gprs[5] &mask);
 874
 875         return regs->gprs[2];
 876 }
 877
 878 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 879 {
 880         audit_syscall_exit(regs);
 881
 882         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 883                 trace_sys_exit(regs, regs->gprs[2]);
 884
 885         if (test_thread_flag(TIF_SYSCALL_TRACE))
 886                 tracehook_report_syscall_exit(regs, 0);
 887 }
 888
 889 /*
 890  * user_regset definitions.
 891  */
 892
 893 static int s390_regs_get(struct task_struct *target,
 894                          const struct user_regset *regset,
 895                          unsigned int pos, unsigned int count,
 896                          void *kbuf, void __user *ubuf)
 897 {
 898         if (target == current)
 899                 save_access_regs(target->thread.acrs);
 900
 901         if (kbuf) {
 902                 unsigned long *k = kbuf;
 903                 while (count > 0) {
 904                         *k++ = __peek_user(target, pos);
 905                         count -= sizeof(*k);
 906                         pos += sizeof(*k);
 907                 }
 908         } else {
 909                 unsigned long __user *u = ubuf;
 910                 while (count > 0) {
 911                         if (__put_user(__peek_user(target, pos), u++))
 912                                 return -EFAULT;
 913                         count -= sizeof(*u);
 914                         pos += sizeof(*u);
 915                 }
 916         }
 917         return 0;
 918 }
 919
 920 static int s390_regs_set(struct task_struct *target,
 921                          const struct user_regset *regset,
 922                          unsigned int pos, unsigned int count,
 923                          const void *kbuf, const void __user *ubuf)
 924 {
 925         int rc = 0;
 926
 927         if (target == current)
 928                 save_access_regs(target->thread.acrs);
 929
 930         if (kbuf) {
 931                 const unsigned long *k = kbuf;
 932                 while (count > 0 && !rc) {
 933                         rc = __poke_user(target, pos, *k++);
 934                         count -= sizeof(*k);
 935                         pos += sizeof(*k);
 936                 }
 937         } else {
 938                 const unsigned long  __user *u = ubuf;
 939                 while (count > 0 && !rc) {
 940                         unsigned long word;
 941                         rc = __get_user(word, u++);
 942                         if (rc)
 943                                 break;
 944                         rc = __poke_user(target, pos, word);
 945                         count -= sizeof(*u);
 946                         pos += sizeof(*u);
 947                 }
 948         }
 949
 950         if (rc == 0 && target == current)
 951                 restore_access_regs(target->thread.acrs);
 952
 953         return rc;
 954 }
 955
 956 static int s390_fpregs_get(struct task_struct *target,
 957                            const struct user_regset *regset, unsigned int pos,
 958                            unsigned int count, void *kbuf, void __user *ubuf)
 959 {
 960         _s390_fp_regs fp_regs;
 961
 962         if (target == current)
 963                 save_fpu_regs();
 964
 965         fp_regs.fpc = target->thread.fpu.fpc;
 966         fpregs_store(&fp_regs, &target->thread.fpu);
 967
 968         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 969                                    &fp_regs, 0, -1);
 970 }
 971
 972 static int s390_fpregs_set(struct task_struct *target,
 973                            const struct user_regset *regset, unsigned int pos,
 974                            unsigned int count, const void *kbuf,
 975                            const void __user *ubuf)
 976 {
 977         int rc = 0;
 978         freg_t fprs[__NUM_FPRS];
 979
 980         if (target == current)
 981                 save_fpu_regs();
 982
 983         if (MACHINE_HAS_VX)
 984                 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
 985         else
 986                 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
 987
 988         /* If setting FPC, must validate it first. */
 989         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 990                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
 991                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
 992                                         0, offsetof(s390_fp_regs, fprs));
 993                 if (rc)
 994                         return rc;
 995                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
 996                         return -EINVAL;
 997                 target->thread.fpu.fpc = ufpc[0];
 998         }
 999
1000         if (rc == 0 && count > 0)
1001                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1002                                         fprs, offsetof(s390_fp_regs, fprs), -1);
1003         if (rc)
1004                 return rc;
1005
1006         if (MACHINE_HAS_VX)
1007                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
1008         else
1009                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
1010
1011         return rc;
1012 }
1013
1014 static int s390_last_break_get(struct task_struct *target,
1015                                const struct user_regset *regset,
1016                                unsigned int pos, unsigned int count,
1017                                void *kbuf, void __user *ubuf)
1018 {
1019         if (count > 0) {
1020                 if (kbuf) {
1021                         unsigned long *k = kbuf;
1022                         *k = target->thread.last_break;
1023                 } else {
1024                         unsigned long  __user *u = ubuf;
1025                         if (__put_user(target->thread.last_break, u))
1026                                 return -EFAULT;
1027                 }
1028         }
1029         return 0;
1030 }
1031
1032 static int s390_last_break_set(struct task_struct *target,
1033                                const struct user_regset *regset,
1034                                unsigned int pos, unsigned int count,
1035                                const void *kbuf, const void __user *ubuf)
1036 {
1037         return 0;
1038 }
1039
1040 static int s390_tdb_get(struct task_struct *target,
1041                         const struct user_regset *regset,
1042                         unsigned int pos, unsigned int count,
1043                         void *kbuf, void __user *ubuf)
1044 {
1045         struct pt_regs *regs = task_pt_regs(target);
1046         unsigned char *data;
1047
1048         if (!(regs->int_code & 0x200))
1049                 return -ENODATA;
1050         data = target->thread.trap_tdb;
1051         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1052 }
1053
1054 static int s390_tdb_set(struct task_struct *target,
1055                         const struct user_regset *regset,
1056                         unsigned int pos, unsigned int count,
1057                         const void *kbuf, const void __user *ubuf)
1058 {
1059         return 0;
1060 }
1061
1062 static int s390_vxrs_low_get(struct task_struct *target,
1063                              const struct user_regset *regset,
1064                              unsigned int pos, unsigned int count,
1065                              void *kbuf, void __user *ubuf)
1066 {
1067         __u64 vxrs[__NUM_VXRS_LOW];
1068         int i;
1069
1070         if (!MACHINE_HAS_VX)
1071                 return -ENODEV;
1072         if (target == current)
1073                 save_fpu_regs();
1074         for (i = 0; i < __NUM_VXRS_LOW; i++)
1075                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1076         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1077 }
1078
1079 static int s390_vxrs_low_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         __u64 vxrs[__NUM_VXRS_LOW];
1085         int i, rc;
1086
1087         if (!MACHINE_HAS_VX)
1088                 return -ENODEV;
1089         if (target == current)
1090                 save_fpu_regs();
1091
1092         for (i = 0; i < __NUM_VXRS_LOW; i++)
1093                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1094
1095         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1096         if (rc == 0)
1097                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1098                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1099
1100         return rc;
1101 }
1102
1103 static int s390_vxrs_high_get(struct task_struct *target,
1104                               const struct user_regset *regset,
1105                               unsigned int pos, unsigned int count,
1106                               void *kbuf, void __user *ubuf)
1107 {
1108         __vector128 vxrs[__NUM_VXRS_HIGH];
1109
1110         if (!MACHINE_HAS_VX)
1111                 return -ENODEV;
1112         if (target == current)
1113                 save_fpu_regs();
1114         memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1115
1116         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1117 }
1118
1119 static int s390_vxrs_high_set(struct task_struct *target,
1120                               const struct user_regset *regset,
1121                               unsigned int pos, unsigned int count,
1122                               const void *kbuf, const void __user *ubuf)
1123 {
1124         int rc;
1125
1126         if (!MACHINE_HAS_VX)
1127                 return -ENODEV;
1128         if (target == current)
1129                 save_fpu_regs();
1130
1131         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1132                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1133         return rc;
1134 }
1135
1136 static int s390_system_call_get(struct task_struct *target,
1137                                 const struct user_regset *regset,
1138                                 unsigned int pos, unsigned int count,
1139                                 void *kbuf, void __user *ubuf)
1140 {
1141         unsigned int *data = &target->thread.system_call;
1142         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1143                                    data, 0, sizeof(unsigned int));
1144 }
1145
1146 static int s390_system_call_set(struct task_struct *target,
1147                                 const struct user_regset *regset,
1148                                 unsigned int pos, unsigned int count,
1149                                 const void *kbuf, const void __user *ubuf)
1150 {
1151         unsigned int *data = &target->thread.system_call;
1152         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1153                                   data, 0, sizeof(unsigned int));
1154 }
1155
1156 static int s390_gs_cb_get(struct task_struct *target,
1157                           const struct user_regset *regset,
1158                           unsigned int pos, unsigned int count,
1159                           void *kbuf, void __user *ubuf)
1160 {
1161         struct gs_cb *data = target->thread.gs_cb;
1162
1163         if (!MACHINE_HAS_GS)
1164                 return -ENODEV;
1165         if (!data)
1166                 return -ENODATA;
1167         if (target == current)
1168                 save_gs_cb(data);
1169         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1170                                    data, 0, sizeof(struct gs_cb));
1171 }
1172
1173 static int s390_gs_cb_set(struct task_struct *target,
1174                           const struct user_regset *regset,
1175                           unsigned int pos, unsigned int count,
1176                           const void *kbuf, const void __user *ubuf)
1177 {
1178         struct gs_cb gs_cb = { }, *data = NULL;
1179         int rc;
1180
1181         if (!MACHINE_HAS_GS)
1182                 return -ENODEV;
1183         if (!target->thread.gs_cb) {
1184                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1185                 if (!data)
1186                         return -ENOMEM;
1187         }
1188         if (!target->thread.gs_cb)
1189                 gs_cb.gsd = 25;
1190         else if (target == current)
1191                 save_gs_cb(&gs_cb);
1192         else
1193                 gs_cb = *target->thread.gs_cb;
1194         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1195                                 &gs_cb, 0, sizeof(gs_cb));
1196         if (rc) {
1197                 kfree(data);
1198                 return -EFAULT;
1199         }
1200         preempt_disable();
1201         if (!target->thread.gs_cb)
1202                 target->thread.gs_cb = data;
1203         *target->thread.gs_cb = gs_cb;
1204         if (target == current) {
1205                 __ctl_set_bit(2, 4);
1206                 restore_gs_cb(target->thread.gs_cb);
1207         }
1208         preempt_enable();
1209         return rc;
1210 }
1211
1212 static int s390_gs_bc_get(struct task_struct *target,
1213                           const struct user_regset *regset,
1214                           unsigned int pos, unsigned int count,
1215                           void *kbuf, void __user *ubuf)
1216 {
1217         struct gs_cb *data = target->thread.gs_bc_cb;
1218
1219         if (!MACHINE_HAS_GS)
1220                 return -ENODEV;
1221         if (!data)
1222                 return -ENODATA;
1223         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1224                                    data, 0, sizeof(struct gs_cb));
1225 }
1226
1227 static int s390_gs_bc_set(struct task_struct *target,
1228                           const struct user_regset *regset,
1229                           unsigned int pos, unsigned int count,
1230                           const void *kbuf, const void __user *ubuf)
1231 {
1232         struct gs_cb *data = target->thread.gs_bc_cb;
1233
1234         if (!MACHINE_HAS_GS)
1235                 return -ENODEV;
1236         if (!data) {
1237                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1238                 if (!data)
1239                         return -ENOMEM;
1240                 target->thread.gs_bc_cb = data;
1241         }
1242         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1243                                   data, 0, sizeof(struct gs_cb));
1244 }
1245
1246 static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1247 {
1248         return (cb->rca & 0x1f) == 0 &&
1249                 (cb->roa & 0xfff) == 0 &&
1250                 (cb->rla & 0xfff) == 0xfff &&
1251                 cb->s == 1 &&
1252                 cb->k == 1 &&
1253                 cb->h == 0 &&
1254                 cb->reserved1 == 0 &&
1255                 cb->ps == 1 &&
1256                 cb->qs == 0 &&
1257                 cb->pc == 1 &&
1258                 cb->qc == 0 &&
1259                 cb->reserved2 == 0 &&
1260                 cb->key == PAGE_DEFAULT_KEY &&
1261                 cb->reserved3 == 0 &&
1262                 cb->reserved4 == 0 &&
1263                 cb->reserved5 == 0 &&
1264                 cb->reserved6 == 0 &&
1265                 cb->reserved7 == 0 &&
1266                 cb->reserved8 == 0 &&
1267                 cb->rla >= cb->roa &&
1268                 cb->rca >= cb->roa &&
1269                 cb->rca <= cb->rla+1 &&
1270                 cb->m < 3;
1271 }
1272
1273 static int s390_runtime_instr_get(struct task_struct *target,
1274                                 const struct user_regset *regset,
1275                                 unsigned int pos, unsigned int count,
1276                                 void *kbuf, void __user *ubuf)
1277 {
1278         struct runtime_instr_cb *data = target->thread.ri_cb;
1279
1280         if (!test_facility(64))
1281                 return -ENODEV;
1282         if (!data)
1283                 return -ENODATA;
1284
1285         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1286                                    data, 0, sizeof(struct runtime_instr_cb));
1287 }
1288
1289 static int s390_runtime_instr_set(struct task_struct *target,
1290                                   const struct user_regset *regset,
1291                                   unsigned int pos, unsigned int count,
1292                                   const void *kbuf, const void __user *ubuf)
1293 {
1294         struct runtime_instr_cb ri_cb = { }, *data = NULL;
1295         int rc;
1296
1297         if (!test_facility(64))
1298                 return -ENODEV;
1299
1300         if (!target->thread.ri_cb) {
1301                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1302                 if (!data)
1303                         return -ENOMEM;
1304         }
1305
1306         if (target->thread.ri_cb) {
1307                 if (target == current)
1308                         store_runtime_instr_cb(&ri_cb);
1309                 else
1310                         ri_cb = *target->thread.ri_cb;
1311         }
1312
1313         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1314                                 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1315         if (rc) {
1316                 kfree(data);
1317                 return -EFAULT;
1318         }
1319
1320         if (!is_ri_cb_valid(&ri_cb)) {
1321                 kfree(data);
1322                 return -EINVAL;
1323         }
1324
1325         preempt_disable();
1326         if (!target->thread.ri_cb)
1327                 target->thread.ri_cb = data;
1328         *target->thread.ri_cb = ri_cb;
1329         if (target == current)
1330                 load_runtime_instr_cb(target->thread.ri_cb);
1331         preempt_enable();
1332
1333         return 0;
1334 }
1335
1336 static const struct user_regset s390_regsets[] = {
1337         {
1338                 .core_note_type = NT_PRSTATUS,
1339                 .n = sizeof(s390_regs) / sizeof(long),
1340                 .size = sizeof(long),
1341                 .align = sizeof(long),
1342                 .get = s390_regs_get,
1343                 .set = s390_regs_set,
1344         },
1345         {
1346                 .core_note_type = NT_PRFPREG,
1347                 .n = sizeof(s390_fp_regs) / sizeof(long),
1348                 .size = sizeof(long),
1349                 .align = sizeof(long),
1350                 .get = s390_fpregs_get,
1351                 .set = s390_fpregs_set,
1352         },
1353         {
1354                 .core_note_type = NT_S390_SYSTEM_CALL,
1355                 .n = 1,
1356                 .size = sizeof(unsigned int),
1357                 .align = sizeof(unsigned int),
1358                 .get = s390_system_call_get,
1359                 .set = s390_system_call_set,
1360         },
1361         {
1362                 .core_note_type = NT_S390_LAST_BREAK,
1363                 .n = 1,
1364                 .size = sizeof(long),
1365                 .align = sizeof(long),
1366                 .get = s390_last_break_get,
1367                 .set = s390_last_break_set,
1368         },
1369         {
1370                 .core_note_type = NT_S390_TDB,
1371                 .n = 1,
1372                 .size = 256,
1373                 .align = 1,
1374                 .get = s390_tdb_get,
1375                 .set = s390_tdb_set,
1376         },
1377         {
1378                 .core_note_type = NT_S390_VXRS_LOW,
1379                 .n = __NUM_VXRS_LOW,
1380                 .size = sizeof(__u64),
1381                 .align = sizeof(__u64),
1382                 .get = s390_vxrs_low_get,
1383                 .set = s390_vxrs_low_set,
1384         },
1385         {
1386                 .core_note_type = NT_S390_VXRS_HIGH,
1387                 .n = __NUM_VXRS_HIGH,
1388                 .size = sizeof(__vector128),
1389                 .align = sizeof(__vector128),
1390                 .get = s390_vxrs_high_get,
1391                 .set = s390_vxrs_high_set,
1392         },
1393         {
1394                 .core_note_type = NT_S390_GS_CB,
1395                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1396                 .size = sizeof(__u64),
1397                 .align = sizeof(__u64),
1398                 .get = s390_gs_cb_get,
1399                 .set = s390_gs_cb_set,
1400         },
1401         {
1402                 .core_note_type = NT_S390_GS_BC,
1403                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1404                 .size = sizeof(__u64),
1405                 .align = sizeof(__u64),
1406                 .get = s390_gs_bc_get,
1407                 .set = s390_gs_bc_set,
1408         },
1409         {
1410                 .core_note_type = NT_S390_RI_CB,
1411                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1412                 .size = sizeof(__u64),
1413                 .align = sizeof(__u64),
1414                 .get = s390_runtime_instr_get,
1415                 .set = s390_runtime_instr_set,
1416         },
1417 };
1418
1419 static const struct user_regset_view user_s390_view = {
1420         .name = UTS_MACHINE,
1421         .e_machine = EM_S390,
1422         .regsets = s390_regsets,
1423         .n = ARRAY_SIZE(s390_regsets)
1424 };
1425
1426 #ifdef CONFIG_COMPAT
1427 static int s390_compat_regs_get(struct task_struct *target,
1428                                 const struct user_regset *regset,
1429                                 unsigned int pos, unsigned int count,
1430                                 void *kbuf, void __user *ubuf)
1431 {
1432         if (target == current)
1433                 save_access_regs(target->thread.acrs);
1434
1435         if (kbuf) {
1436                 compat_ulong_t *k = kbuf;
1437                 while (count > 0) {
1438                         *k++ = __peek_user_compat(target, pos);
1439                         count -= sizeof(*k);
1440                         pos += sizeof(*k);
1441                 }
1442         } else {
1443                 compat_ulong_t __user *u = ubuf;
1444                 while (count > 0) {
1445                         if (__put_user(__peek_user_compat(target, pos), u++))
1446                                 return -EFAULT;
1447                         count -= sizeof(*u);
1448                         pos += sizeof(*u);
1449                 }
1450         }
1451         return 0;
1452 }
1453
1454 static int s390_compat_regs_set(struct task_struct *target,
1455                                 const struct user_regset *regset,
1456                                 unsigned int pos, unsigned int count,
1457                                 const void *kbuf, const void __user *ubuf)
1458 {
1459         int rc = 0;
1460
1461         if (target == current)
1462                 save_access_regs(target->thread.acrs);
1463
1464         if (kbuf) {
1465                 const compat_ulong_t *k = kbuf;
1466                 while (count > 0 && !rc) {
1467                         rc = __poke_user_compat(target, pos, *k++);
1468                         count -= sizeof(*k);
1469                         pos += sizeof(*k);
1470                 }
1471         } else {
1472                 const compat_ulong_t  __user *u = ubuf;
1473                 while (count > 0 && !rc) {
1474                         compat_ulong_t word;
1475                         rc = __get_user(word, u++);
1476                         if (rc)
1477                                 break;
1478                         rc = __poke_user_compat(target, pos, word);
1479                         count -= sizeof(*u);
1480                         pos += sizeof(*u);
1481                 }
1482         }
1483
1484         if (rc == 0 && target == current)
1485                 restore_access_regs(target->thread.acrs);
1486
1487         return rc;
1488 }
1489
1490 static int s390_compat_regs_high_get(struct task_struct *target,
1491                                      const struct user_regset *regset,
1492                                      unsigned int pos, unsigned int count,
1493                                      void *kbuf, void __user *ubuf)
1494 {
1495         compat_ulong_t *gprs_high;
1496
1497         gprs_high = (compat_ulong_t *)
1498                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1499         if (kbuf) {
1500                 compat_ulong_t *k = kbuf;
1501                 while (count > 0) {
1502                         *k++ = *gprs_high;
1503                         gprs_high += 2;
1504                         count -= sizeof(*k);
1505                 }
1506         } else {
1507                 compat_ulong_t __user *u = ubuf;
1508                 while (count > 0) {
1509                         if (__put_user(*gprs_high, u++))
1510                                 return -EFAULT;
1511                         gprs_high += 2;
1512                         count -= sizeof(*u);
1513                 }
1514         }
1515         return 0;
1516 }
1517
1518 static int s390_compat_regs_high_set(struct task_struct *target,
1519                                      const struct user_regset *regset,
1520                                      unsigned int pos, unsigned int count,
1521                                      const void *kbuf, const void __user *ubuf)
1522 {
1523         compat_ulong_t *gprs_high;
1524         int rc = 0;
1525
1526         gprs_high = (compat_ulong_t *)
1527                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1528         if (kbuf) {
1529                 const compat_ulong_t *k = kbuf;
1530                 while (count > 0) {
1531                         *gprs_high = *k++;
1532                         *gprs_high += 2;
1533                         count -= sizeof(*k);
1534                 }
1535         } else {
1536                 const compat_ulong_t  __user *u = ubuf;
1537                 while (count > 0 && !rc) {
1538                         unsigned long word;
1539                         rc = __get_user(word, u++);
1540                         if (rc)
1541                                 break;
1542                         *gprs_high = word;
1543                         *gprs_high += 2;
1544                         count -= sizeof(*u);
1545                 }
1546         }
1547
1548         return rc;
1549 }
1550
1551 static int s390_compat_last_break_get(struct task_struct *target,
1552                                       const struct user_regset *regset,
1553                                       unsigned int pos, unsigned int count,
1554                                       void *kbuf, void __user *ubuf)
1555 {
1556         compat_ulong_t last_break;
1557
1558         if (count > 0) {
1559                 last_break = target->thread.last_break;
1560                 if (kbuf) {
1561                         unsigned long *k = kbuf;
1562                         *k = last_break;
1563                 } else {
1564                         unsigned long  __user *u = ubuf;
1565                         if (__put_user(last_break, u))
1566                                 return -EFAULT;
1567                 }
1568         }
1569         return 0;
1570 }
1571
1572 static int s390_compat_last_break_set(struct task_struct *target,
1573                                       const struct user_regset *regset,
1574                                       unsigned int pos, unsigned int count,
1575                                       const void *kbuf, const void __user *ubuf)
1576 {
1577         return 0;
1578 }
1579
1580 static const struct user_regset s390_compat_regsets[] = {
1581         {
1582                 .core_note_type = NT_PRSTATUS,
1583                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1584                 .size = sizeof(compat_long_t),
1585                 .align = sizeof(compat_long_t),
1586                 .get = s390_compat_regs_get,
1587                 .set = s390_compat_regs_set,
1588         },
1589         {
1590                 .core_note_type = NT_PRFPREG,
1591                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1592                 .size = sizeof(compat_long_t),
1593                 .align = sizeof(compat_long_t),
1594                 .get = s390_fpregs_get,
1595                 .set = s390_fpregs_set,
1596         },
1597         {
1598                 .core_note_type = NT_S390_SYSTEM_CALL,
1599                 .n = 1,
1600                 .size = sizeof(compat_uint_t),
1601                 .align = sizeof(compat_uint_t),
1602                 .get = s390_system_call_get,
1603                 .set = s390_system_call_set,
1604         },
1605         {
1606                 .core_note_type = NT_S390_LAST_BREAK,
1607                 .n = 1,
1608                 .size = sizeof(long),
1609                 .align = sizeof(long),
1610                 .get = s390_compat_last_break_get,
1611                 .set = s390_compat_last_break_set,
1612         },
1613         {
1614                 .core_note_type = NT_S390_TDB,
1615                 .n = 1,
1616                 .size = 256,
1617                 .align = 1,
1618                 .get = s390_tdb_get,
1619                 .set = s390_tdb_set,
1620         },
1621         {
1622                 .core_note_type = NT_S390_VXRS_LOW,
1623                 .n = __NUM_VXRS_LOW,
1624                 .size = sizeof(__u64),
1625                 .align = sizeof(__u64),
1626                 .get = s390_vxrs_low_get,
1627                 .set = s390_vxrs_low_set,
1628         },
1629         {
1630                 .core_note_type = NT_S390_VXRS_HIGH,
1631                 .n = __NUM_VXRS_HIGH,
1632                 .size = sizeof(__vector128),
1633                 .align = sizeof(__vector128),
1634                 .get = s390_vxrs_high_get,
1635                 .set = s390_vxrs_high_set,
1636         },
1637         {
1638                 .core_note_type = NT_S390_HIGH_GPRS,
1639                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1640                 .size = sizeof(compat_long_t),
1641                 .align = sizeof(compat_long_t),
1642                 .get = s390_compat_regs_high_get,
1643                 .set = s390_compat_regs_high_set,
1644         },
1645         {
1646                 .core_note_type = NT_S390_GS_CB,
1647                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1648                 .size = sizeof(__u64),
1649                 .align = sizeof(__u64),
1650                 .get = s390_gs_cb_get,
1651                 .set = s390_gs_cb_set,
1652         },
1653         {
1654                 .core_note_type = NT_S390_RI_CB,
1655                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1656                 .size = sizeof(__u64),
1657                 .align = sizeof(__u64),
1658                 .get = s390_runtime_instr_get,
1659                 .set = s390_runtime_instr_set,
1660         },
1661 };
1662
1663 static const struct user_regset_view user_s390_compat_view = {
1664         .name = "s390",
1665         .e_machine = EM_S390,
1666         .regsets = s390_compat_regsets,
1667         .n = ARRAY_SIZE(s390_compat_regsets)
1668 };
1669 #endif
1670
1671 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1672 {
1673 #ifdef CONFIG_COMPAT
1674         if (test_tsk_thread_flag(task, TIF_31BIT))
1675                 return &user_s390_compat_view;
1676 #endif
1677         return &user_s390_view;
1678 }
1679
1680 static const char *gpr_names[NUM_GPRS] = {
1681         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1682         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1683 };
1684
1685 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1686 {
1687         if (offset >= NUM_GPRS)
1688                 return 0;
1689         return regs->gprs[offset];
1690 }
1691
1692 int regs_query_register_offset(const char *name)
1693 {
1694         unsigned long offset;
1695
1696         if (!name || *name != 'r')
1697                 return -EINVAL;
1698         if (kstrtoul(name + 1, 10, &offset))
1699                 return -EINVAL;
1700         if (offset >= NUM_GPRS)
1701                 return -EINVAL;
1702         return offset;
1703 }
1704
1705 const char *regs_query_register_name(unsigned int offset)
1706 {
1707         if (offset >= NUM_GPRS)
1708                 return NULL;
1709         return gpr_names[offset];
1710 }
1711
1712 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1713 {
1714         unsigned long ksp = kernel_stack_pointer(regs);
1715
1716         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1717 }
1718
1719 /**
1720  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1721  * @regs:pt_regs which contains kernel stack pointer.
1722  * @n:stack entry number.
1723  *
1724  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1725  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1726  * this returns 0.
1727  */
1728 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1729 {
1730         unsigned long addr;
1731
1732         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1733         if (!regs_within_kernel_stack(regs, addr))
1734                 return 0;
1735         return *(unsigned long *)addr;
1736 }