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 "asm/ptrace.h"
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/sched/task_stack.h>
  14 #include <linux/mm.h>
  15 #include <linux/smp.h>
  16 #include <linux/errno.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/user.h>
  19 #include <linux/security.h>
  20 #include <linux/audit.h>
  21 #include <linux/signal.h>
  22 #include <linux/elf.h>
  23 #include <linux/regset.h>
  24 #include <linux/seccomp.h>
  25 #include <linux/compat.h>
  26 #include <trace/syscall.h>
  27 #include <asm/page.h>
  28 #include <linux/uaccess.h>
  29 #include <asm/unistd.h>
  30 #include <asm/switch_to.h>
  31 #include <asm/runtime_instr.h>
  32 #include <asm/facility.h>
  33
  34 #include "entry.h"
  35
  36 #ifdef CONFIG_COMPAT
  37 #include "compat_ptrace.h"
  38 #endif
  39
  40 void update_cr_regs(struct task_struct *task)
  41 {
  42         struct pt_regs *regs = task_pt_regs(task);
  43         struct thread_struct *thread = &task->thread;
  44         struct per_regs old, new;
  45         union ctlreg0 cr0_old, cr0_new;
  46         union ctlreg2 cr2_old, cr2_new;
  47         int cr0_changed, cr2_changed;
  48
  49         __ctl_store(cr0_old.val, 0, 0);
  50         __ctl_store(cr2_old.val, 2, 2);
  51         cr0_new = cr0_old;
  52         cr2_new = cr2_old;
  53         /* Take care of the enable/disable of transactional execution. */
  54         if (MACHINE_HAS_TE) {
  55                 /* Set or clear transaction execution TXC bit 8. */
  56                 cr0_new.tcx = 1;
  57                 if (task->thread.per_flags & PER_FLAG_NO_TE)
  58                         cr0_new.tcx = 0;
  59                 /* Set or clear transaction execution TDC bits 62 and 63. */
  60                 cr2_new.tdc = 0;
  61                 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
  62                         if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
  63                                 cr2_new.tdc = 1;
  64                         else
  65                                 cr2_new.tdc = 2;
  66                 }
  67         }
  68         /* Take care of enable/disable of guarded storage. */
  69         if (MACHINE_HAS_GS) {
  70                 cr2_new.gse = 0;
  71                 if (task->thread.gs_cb)
  72                         cr2_new.gse = 1;
  73         }
  74         /* Load control register 0/2 iff changed */
  75         cr0_changed = cr0_new.val != cr0_old.val;
  76         cr2_changed = cr2_new.val != cr2_old.val;
  77         if (cr0_changed)
  78                 __ctl_load(cr0_new.val, 0, 0);
  79         if (cr2_changed)
  80                 __ctl_load(cr2_new.val, 2, 2);
  81         /* Copy user specified PER registers */
  82         new.control = thread->per_user.control;
  83         new.start = thread->per_user.start;
  84         new.end = thread->per_user.end;
  85
  86         /* merge TIF_SINGLE_STEP into user specified PER registers. */
  87         if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
  88             test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
  89                 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
  90                         new.control |= PER_EVENT_BRANCH;
  91                 else
  92                         new.control |= PER_EVENT_IFETCH;
  93                 new.control |= PER_CONTROL_SUSPENSION;
  94                 new.control |= PER_EVENT_TRANSACTION_END;
  95                 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
  96                         new.control |= PER_EVENT_IFETCH;
  97                 new.start = 0;
  98                 new.end = -1UL;
  99         }
 100
 101         /* Take care of the PER enablement bit in the PSW. */
 102         if (!(new.control & PER_EVENT_MASK)) {
 103                 regs->psw.mask &= ~PSW_MASK_PER;
 104                 return;
 105         }
 106         regs->psw.mask |= PSW_MASK_PER;
 107         __ctl_store(old, 9, 11);
 108         if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
 109                 __ctl_load(new, 9, 11);
 110 }
 111
 112 void user_enable_single_step(struct task_struct *task)
 113 {
 114         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 115         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 116 }
 117
 118 void user_disable_single_step(struct task_struct *task)
 119 {
 120         clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
 121         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 122 }
 123
 124 void user_enable_block_step(struct task_struct *task)
 125 {
 126         set_tsk_thread_flag(task, TIF_SINGLE_STEP);
 127         set_tsk_thread_flag(task, TIF_BLOCK_STEP);
 128 }
 129
 130 /*
 131  * Called by kernel/ptrace.c when detaching..
 132  *
 133  * Clear all debugging related fields.
 134  */
 135 void ptrace_disable(struct task_struct *task)
 136 {
 137         memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 138         memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 139         clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 140         clear_tsk_thread_flag(task, TIF_PER_TRAP);
 141         task->thread.per_flags = 0;
 142 }
 143
 144 #define __ADDR_MASK 7
 145
 146 static inline unsigned long __peek_user_per(struct task_struct *child,
 147                                             addr_t addr)
 148 {
 149         if (addr == offsetof(struct per_struct_kernel, cr9))
 150                 /* Control bits of the active per set. */
 151                 return test_thread_flag(TIF_SINGLE_STEP) ?
 152                         PER_EVENT_IFETCH : child->thread.per_user.control;
 153         else if (addr == offsetof(struct per_struct_kernel, cr10))
 154                 /* Start address of the active per set. */
 155                 return test_thread_flag(TIF_SINGLE_STEP) ?
 156                         0 : child->thread.per_user.start;
 157         else if (addr == offsetof(struct per_struct_kernel, cr11))
 158                 /* End address of the active per set. */
 159                 return test_thread_flag(TIF_SINGLE_STEP) ?
 160                         -1UL : child->thread.per_user.end;
 161         else if (addr == offsetof(struct per_struct_kernel, bits))
 162                 /* Single-step bit. */
 163                 return test_thread_flag(TIF_SINGLE_STEP) ?
 164                         (1UL << (BITS_PER_LONG - 1)) : 0;
 165         else if (addr == offsetof(struct per_struct_kernel, starting_addr))
 166                 /* Start address of the user specified per set. */
 167                 return child->thread.per_user.start;
 168         else if (addr == offsetof(struct per_struct_kernel, ending_addr))
 169                 /* End address of the user specified per set. */
 170                 return child->thread.per_user.end;
 171         else if (addr == offsetof(struct per_struct_kernel, perc_atmid))
 172                 /* PER code, ATMID and AI of the last PER trap */
 173                 return (unsigned long)
 174                         child->thread.per_event.cause << (BITS_PER_LONG - 16);
 175         else if (addr == offsetof(struct per_struct_kernel, address))
 176                 /* Address of the last PER trap */
 177                 return child->thread.per_event.address;
 178         else if (addr == offsetof(struct per_struct_kernel, access_id))
 179                 /* Access id of the last PER trap */
 180                 return (unsigned long)
 181                         child->thread.per_event.paid << (BITS_PER_LONG - 8);
 182         return 0;
 183 }
 184
 185 /*
 186  * Read the word at offset addr from the user area of a process. The
 187  * trouble here is that the information is littered over different
 188  * locations. The process registers are found on the kernel stack,
 189  * the floating point stuff and the trace settings are stored in
 190  * the task structure. In addition the different structures in
 191  * struct user contain pad bytes that should be read as zeroes.
 192  * Lovely...
 193  */
 194 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 195 {
 196         addr_t offset, tmp;
 197
 198         if (addr < offsetof(struct user, regs.acrs)) {
 199                 /*
 200                  * psw and gprs are stored on the stack
 201                  */
 202                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 203                 if (addr == offsetof(struct user, regs.psw.mask)) {
 204                         /* Return a clean psw mask. */
 205                         tmp &= PSW_MASK_USER | PSW_MASK_RI;
 206                         tmp |= PSW_USER_BITS;
 207                 }
 208
 209         } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
 210                 /*
 211                  * access registers are stored in the thread structure
 212                  */
 213                 offset = addr - offsetof(struct user, regs.acrs);
 214                 /*
 215                  * Very special case: old & broken 64 bit gdb reading
 216                  * from acrs[15]. Result is a 64 bit value. Read the
 217                  * 32 bit acrs[15] value and shift it by 32. Sick...
 218                  */
 219                 if (addr == offsetof(struct user, regs.acrs[15]))
 220                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 221                 else
 222                         tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 223
 224         } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
 225                 /*
 226                  * orig_gpr2 is stored on the kernel stack
 227                  */
 228                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 229
 230         } else if (addr < offsetof(struct user, regs.fp_regs)) {
 231                 /*
 232                  * prevent reads of padding hole between
 233                  * orig_gpr2 and fp_regs on s390.
 234                  */
 235                 tmp = 0;
 236
 237         } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
 238                 /*
 239                  * floating point control reg. is in the thread structure
 240                  */
 241                 tmp = child->thread.fpu.fpc;
 242                 tmp <<= BITS_PER_LONG - 32;
 243
 244         } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
 245                 /*
 246                  * floating point regs. are either in child->thread.fpu
 247                  * or the child->thread.fpu.vxrs array
 248                  */
 249                 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
 250                 if (MACHINE_HAS_VX)
 251                         tmp = *(addr_t *)
 252                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 253                 else
 254                         tmp = *(addr_t *)
 255                                ((addr_t) child->thread.fpu.fprs + offset);
 256
 257         } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
 258                 /*
 259                  * Handle access to the per_info structure.
 260                  */
 261                 addr -= offsetof(struct user, regs.per_info);
 262                 tmp = __peek_user_per(child, addr);
 263
 264         } else
 265                 tmp = 0;
 266
 267         return tmp;
 268 }
 269
 270 static int
 271 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 272 {
 273         addr_t tmp, mask;
 274
 275         /*
 276          * Stupid gdb peeks/pokes the access registers in 64 bit with
 277          * an alignment of 4. Programmers from hell...
 278          */
 279         mask = __ADDR_MASK;
 280         if (addr >= offsetof(struct user, regs.acrs) &&
 281             addr < offsetof(struct user, regs.orig_gpr2))
 282                 mask = 3;
 283         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 284                 return -EIO;
 285
 286         tmp = __peek_user(child, addr);
 287         return put_user(tmp, (addr_t __user *) data);
 288 }
 289
 290 static inline void __poke_user_per(struct task_struct *child,
 291                                    addr_t addr, addr_t data)
 292 {
 293         /*
 294          * There are only three fields in the per_info struct that the
 295          * debugger user can write to.
 296          * 1) cr9: the debugger wants to set a new PER event mask
 297          * 2) starting_addr: the debugger wants to set a new starting
 298          *    address to use with the PER event mask.
 299          * 3) ending_addr: the debugger wants to set a new ending
 300          *    address to use with the PER event mask.
 301          * The user specified PER event mask and the start and end
 302          * addresses are used only if single stepping is not in effect.
 303          * Writes to any other field in per_info are ignored.
 304          */
 305         if (addr == offsetof(struct per_struct_kernel, cr9))
 306                 /* PER event mask of the user specified per set. */
 307                 child->thread.per_user.control =
 308                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 309         else if (addr == offsetof(struct per_struct_kernel, starting_addr))
 310                 /* Starting address of the user specified per set. */
 311                 child->thread.per_user.start = data;
 312         else if (addr == offsetof(struct per_struct_kernel, ending_addr))
 313                 /* Ending address of the user specified per set. */
 314                 child->thread.per_user.end = data;
 315 }
 316
 317 /*
 318  * Write a word to the user area of a process at location addr. This
 319  * operation does have an additional problem compared to peek_user.
 320  * Stores to the program status word and on the floating point
 321  * control register needs to get checked for validity.
 322  */
 323 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 324 {
 325         addr_t offset;
 326
 327
 328         if (addr < offsetof(struct user, regs.acrs)) {
 329                 struct pt_regs *regs = task_pt_regs(child);
 330                 /*
 331                  * psw and gprs are stored on the stack
 332                  */
 333                 if (addr == offsetof(struct user, regs.psw.mask)) {
 334                         unsigned long mask = PSW_MASK_USER;
 335
 336                         mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
 337                         if ((data ^ PSW_USER_BITS) & ~mask)
 338                                 /* Invalid psw mask. */
 339                                 return -EINVAL;
 340                         if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
 341                                 /* Invalid address-space-control bits */
 342                                 return -EINVAL;
 343                         if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
 344                                 /* Invalid addressing mode bits */
 345                                 return -EINVAL;
 346                 }
 347
 348                 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
 349                         addr == offsetof(struct user, regs.gprs[2])) {
 350                         struct pt_regs *regs = task_pt_regs(child);
 351
 352                         regs->int_code = 0x20000 | (data & 0xffff);
 353                 }
 354                 *(addr_t *)((addr_t) &regs->psw + addr) = data;
 355         } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
 356                 /*
 357                  * access registers are stored in the thread structure
 358                  */
 359                 offset = addr - offsetof(struct user, regs.acrs);
 360                 /*
 361                  * Very special case: old & broken 64 bit gdb writing
 362                  * to acrs[15] with a 64 bit value. Ignore the lower
 363                  * half of the value and write the upper 32 bit to
 364                  * acrs[15]. Sick...
 365                  */
 366                 if (addr == offsetof(struct user, regs.acrs[15]))
 367                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 368                 else
 369                         *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 370
 371         } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
 372                 /*
 373                  * orig_gpr2 is stored on the kernel stack
 374                  */
 375                 task_pt_regs(child)->orig_gpr2 = data;
 376
 377         } else if (addr < offsetof(struct user, regs.fp_regs)) {
 378                 /*
 379                  * prevent writes of padding hole between
 380                  * orig_gpr2 and fp_regs on s390.
 381                  */
 382                 return 0;
 383
 384         } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
 385                 /*
 386                  * floating point control reg. is in the thread structure
 387                  */
 388                 save_fpu_regs();
 389                 if ((unsigned int) data != 0 ||
 390                     test_fp_ctl(data >> (BITS_PER_LONG - 32)))
 391                         return -EINVAL;
 392                 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
 393
 394         } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
 395                 /*
 396                  * floating point regs. are either in child->thread.fpu
 397                  * or the child->thread.fpu.vxrs array
 398                  */
 399                 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
 400                 if (MACHINE_HAS_VX)
 401                         *(addr_t *)((addr_t)
 402                                 child->thread.fpu.vxrs + 2*offset) = data;
 403                 else
 404                         *(addr_t *)((addr_t)
 405                                 child->thread.fpu.fprs + offset) = data;
 406
 407         } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
 408                 /*
 409                  * Handle access to the per_info structure.
 410                  */
 411                 addr -= offsetof(struct user, regs.per_info);
 412                 __poke_user_per(child, addr, data);
 413
 414         }
 415
 416         return 0;
 417 }
 418
 419 static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 420 {
 421         addr_t mask;
 422
 423         /*
 424          * Stupid gdb peeks/pokes the access registers in 64 bit with
 425          * an alignment of 4. Programmers from hell indeed...
 426          */
 427         mask = __ADDR_MASK;
 428         if (addr >= offsetof(struct user, regs.acrs) &&
 429             addr < offsetof(struct user, regs.orig_gpr2))
 430                 mask = 3;
 431         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 432                 return -EIO;
 433
 434         return __poke_user(child, addr, data);
 435 }
 436
 437 long arch_ptrace(struct task_struct *child, long request,
 438                  unsigned long addr, unsigned long data)
 439 {
 440         ptrace_area parea;
 441         int copied, ret;
 442
 443         switch (request) {
 444         case PTRACE_PEEKUSR:
 445                 /* read the word at location addr in the USER area. */
 446                 return peek_user(child, addr, data);
 447
 448         case PTRACE_POKEUSR:
 449                 /* write the word at location addr in the USER area */
 450                 return poke_user(child, addr, data);
 451
 452         case PTRACE_PEEKUSR_AREA:
 453         case PTRACE_POKEUSR_AREA:
 454                 if (copy_from_user(&parea, (void __force __user *) addr,
 455                                                         sizeof(parea)))
 456                         return -EFAULT;
 457                 addr = parea.kernel_addr;
 458                 data = parea.process_addr;
 459                 copied = 0;
 460                 while (copied < parea.len) {
 461                         if (request == PTRACE_PEEKUSR_AREA)
 462                                 ret = peek_user(child, addr, data);
 463                         else {
 464                                 addr_t utmp;
 465                                 if (get_user(utmp,
 466                                              (addr_t __force __user *) data))
 467                                         return -EFAULT;
 468                                 ret = poke_user(child, addr, utmp);
 469                         }
 470                         if (ret)
 471                                 return ret;
 472                         addr += sizeof(unsigned long);
 473                         data += sizeof(unsigned long);
 474                         copied += sizeof(unsigned long);
 475                 }
 476                 return 0;
 477         case PTRACE_GET_LAST_BREAK:
 478                 return put_user(child->thread.last_break, (unsigned long __user *)data);
 479         case PTRACE_ENABLE_TE:
 480                 if (!MACHINE_HAS_TE)
 481                         return -EIO;
 482                 child->thread.per_flags &= ~PER_FLAG_NO_TE;
 483                 return 0;
 484         case PTRACE_DISABLE_TE:
 485                 if (!MACHINE_HAS_TE)
 486                         return -EIO;
 487                 child->thread.per_flags |= PER_FLAG_NO_TE;
 488                 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 489                 return 0;
 490         case PTRACE_TE_ABORT_RAND:
 491                 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
 492                         return -EIO;
 493                 switch (data) {
 494                 case 0UL:
 495                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
 496                         break;
 497                 case 1UL:
 498                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 499                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
 500                         break;
 501                 case 2UL:
 502                         child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
 503                         child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
 504                         break;
 505                 default:
 506                         return -EINVAL;
 507                 }
 508                 return 0;
 509         default:
 510                 return ptrace_request(child, request, addr, data);
 511         }
 512 }
 513
 514 #ifdef CONFIG_COMPAT
 515 /*
 516  * Now the fun part starts... a 31 bit program running in the
 517  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 518  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 519  * to handle, the difference to the 64 bit versions of the requests
 520  * is that the access is done in multiples of 4 byte instead of
 521  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 522  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 523  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 524  * is a 31 bit program too, the content of struct user can be
 525  * emulated. A 31 bit program peeking into the struct user of
 526  * a 64 bit program is a no-no.
 527  */
 528
 529 /*
 530  * Same as peek_user_per but for a 31 bit program.
 531  */
 532 static inline __u32 __peek_user_per_compat(struct task_struct *child,
 533                                            addr_t addr)
 534 {
 535         if (addr == offsetof(struct compat_per_struct_kernel, cr9))
 536                 /* Control bits of the active per set. */
 537                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 538                         PER_EVENT_IFETCH : child->thread.per_user.control;
 539         else if (addr == offsetof(struct compat_per_struct_kernel, cr10))
 540                 /* Start address of the active per set. */
 541                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 542                         0 : child->thread.per_user.start;
 543         else if (addr == offsetof(struct compat_per_struct_kernel, cr11))
 544                 /* End address of the active per set. */
 545                 return test_thread_flag(TIF_SINGLE_STEP) ?
 546                         PSW32_ADDR_INSN : child->thread.per_user.end;
 547         else if (addr == offsetof(struct compat_per_struct_kernel, bits))
 548                 /* Single-step bit. */
 549                 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 550                         0x80000000 : 0;
 551         else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
 552                 /* Start address of the user specified per set. */
 553                 return (__u32) child->thread.per_user.start;
 554         else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
 555                 /* End address of the user specified per set. */
 556                 return (__u32) child->thread.per_user.end;
 557         else if (addr == offsetof(struct compat_per_struct_kernel, perc_atmid))
 558                 /* PER code, ATMID and AI of the last PER trap */
 559                 return (__u32) child->thread.per_event.cause << 16;
 560         else if (addr == offsetof(struct compat_per_struct_kernel, address))
 561                 /* Address of the last PER trap */
 562                 return (__u32) child->thread.per_event.address;
 563         else if (addr == offsetof(struct compat_per_struct_kernel, access_id))
 564                 /* Access id of the last PER trap */
 565                 return (__u32) child->thread.per_event.paid << 24;
 566         return 0;
 567 }
 568
 569 /*
 570  * Same as peek_user but for a 31 bit program.
 571  */
 572 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 573 {
 574         addr_t offset;
 575         __u32 tmp;
 576
 577         if (addr < offsetof(struct compat_user, regs.acrs)) {
 578                 struct pt_regs *regs = task_pt_regs(child);
 579                 /*
 580                  * psw and gprs are stored on the stack
 581                  */
 582                 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
 583                         /* Fake a 31 bit psw mask. */
 584                         tmp = (__u32)(regs->psw.mask >> 32);
 585                         tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
 586                         tmp |= PSW32_USER_BITS;
 587                 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
 588                         /* Fake a 31 bit psw address. */
 589                         tmp = (__u32) regs->psw.addr |
 590                                 (__u32)(regs->psw.mask & PSW_MASK_BA);
 591                 } else {
 592                         /* gpr 0-15 */
 593                         tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 594                 }
 595         } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
 596                 /*
 597                  * access registers are stored in the thread structure
 598                  */
 599                 offset = addr - offsetof(struct compat_user, regs.acrs);
 600                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 601
 602         } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
 603                 /*
 604                  * orig_gpr2 is stored on the kernel stack
 605                  */
 606                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 607
 608         } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
 609                 /*
 610                  * prevent reads of padding hole between
 611                  * orig_gpr2 and fp_regs on s390.
 612                  */
 613                 tmp = 0;
 614
 615         } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
 616                 /*
 617                  * floating point control reg. is in the thread structure
 618                  */
 619                 tmp = child->thread.fpu.fpc;
 620
 621         } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
 622                 /*
 623                  * floating point regs. are either in child->thread.fpu
 624                  * or the child->thread.fpu.vxrs array
 625                  */
 626                 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
 627                 if (MACHINE_HAS_VX)
 628                         tmp = *(__u32 *)
 629                                ((addr_t) child->thread.fpu.vxrs + 2*offset);
 630                 else
 631                         tmp = *(__u32 *)
 632                                ((addr_t) child->thread.fpu.fprs + offset);
 633
 634         } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
 635                 /*
 636                  * Handle access to the per_info structure.
 637                  */
 638                 addr -= offsetof(struct compat_user, regs.per_info);
 639                 tmp = __peek_user_per_compat(child, addr);
 640
 641         } else
 642                 tmp = 0;
 643
 644         return tmp;
 645 }
 646
 647 static int peek_user_compat(struct task_struct *child,
 648                             addr_t addr, addr_t data)
 649 {
 650         __u32 tmp;
 651
 652         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 653                 return -EIO;
 654
 655         tmp = __peek_user_compat(child, addr);
 656         return put_user(tmp, (__u32 __user *) data);
 657 }
 658
 659 /*
 660  * Same as poke_user_per but for a 31 bit program.
 661  */
 662 static inline void __poke_user_per_compat(struct task_struct *child,
 663                                           addr_t addr, __u32 data)
 664 {
 665         if (addr == offsetof(struct compat_per_struct_kernel, cr9))
 666                 /* PER event mask of the user specified per set. */
 667                 child->thread.per_user.control =
 668                         data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 669         else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
 670                 /* Starting address of the user specified per set. */
 671                 child->thread.per_user.start = data;
 672         else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
 673                 /* Ending address of the user specified per set. */
 674                 child->thread.per_user.end = data;
 675 }
 676
 677 /*
 678  * Same as poke_user but for a 31 bit program.
 679  */
 680 static int __poke_user_compat(struct task_struct *child,
 681                               addr_t addr, addr_t data)
 682 {
 683         __u32 tmp = (__u32) data;
 684         addr_t offset;
 685
 686         if (addr < offsetof(struct compat_user, regs.acrs)) {
 687                 struct pt_regs *regs = task_pt_regs(child);
 688                 /*
 689                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 690                  */
 691                 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
 692                         __u32 mask = PSW32_MASK_USER;
 693
 694                         mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
 695                         /* Build a 64 bit psw mask from 31 bit mask. */
 696                         if ((tmp ^ PSW32_USER_BITS) & ~mask)
 697                                 /* Invalid psw mask. */
 698                                 return -EINVAL;
 699                         if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
 700                                 /* Invalid address-space-control bits */
 701                                 return -EINVAL;
 702                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 703                                 (regs->psw.mask & PSW_MASK_BA) |
 704                                 (__u64)(tmp & mask) << 32;
 705                 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
 706                         /* Build a 64 bit psw address from 31 bit address. */
 707                         regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 708                         /* Transfer 31 bit amode bit to psw mask. */
 709                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 710                                 (__u64)(tmp & PSW32_ADDR_AMODE);
 711                 } else {
 712                         if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
 713                                 addr == offsetof(struct compat_user, regs.gprs[2])) {
 714                                 struct pt_regs *regs = task_pt_regs(child);
 715
 716                                 regs->int_code = 0x20000 | (data & 0xffff);
 717                         }
 718                         /* gpr 0-15 */
 719                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 720                 }
 721         } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
 722                 /*
 723                  * access registers are stored in the thread structure
 724                  */
 725                 offset = addr - offsetof(struct compat_user, regs.acrs);
 726                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 727
 728         } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
 729                 /*
 730                  * orig_gpr2 is stored on the kernel stack
 731                  */
 732                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 733
 734         } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
 735                 /*
 736                  * prevent writess of padding hole between
 737                  * orig_gpr2 and fp_regs on s390.
 738                  */
 739                 return 0;
 740
 741         } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
 742                 /*
 743                  * floating point control reg. is in the thread structure
 744                  */
 745                 save_fpu_regs();
 746                 if (test_fp_ctl(tmp))
 747                         return -EINVAL;
 748                 child->thread.fpu.fpc = data;
 749
 750         } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
 751                 /*
 752                  * floating point regs. are either in child->thread.fpu
 753                  * or the child->thread.fpu.vxrs array
 754                  */
 755                 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
 756                 if (MACHINE_HAS_VX)
 757                         *(__u32 *)((addr_t)
 758                                 child->thread.fpu.vxrs + 2*offset) = tmp;
 759                 else
 760                         *(__u32 *)((addr_t)
 761                                 child->thread.fpu.fprs + offset) = tmp;
 762
 763         } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
 764                 /*
 765                  * Handle access to the per_info structure.
 766                  */
 767                 addr -= offsetof(struct compat_user, regs.per_info);
 768                 __poke_user_per_compat(child, addr, data);
 769         }
 770
 771         return 0;
 772 }
 773
 774 static int poke_user_compat(struct task_struct *child,
 775                             addr_t addr, addr_t data)
 776 {
 777         if (!is_compat_task() || (addr & 3) ||
 778             addr > sizeof(struct compat_user) - 3)
 779                 return -EIO;
 780
 781         return __poke_user_compat(child, addr, data);
 782 }
 783
 784 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 785                         compat_ulong_t caddr, compat_ulong_t cdata)
 786 {
 787         unsigned long addr = caddr;
 788         unsigned long data = cdata;
 789         compat_ptrace_area parea;
 790         int copied, ret;
 791
 792         switch (request) {
 793         case PTRACE_PEEKUSR:
 794                 /* read the word at location addr in the USER area. */
 795                 return peek_user_compat(child, addr, data);
 796
 797         case PTRACE_POKEUSR:
 798                 /* write the word at location addr in the USER area */
 799                 return poke_user_compat(child, addr, data);
 800
 801         case PTRACE_PEEKUSR_AREA:
 802         case PTRACE_POKEUSR_AREA:
 803                 if (copy_from_user(&parea, (void __force __user *) addr,
 804                                                         sizeof(parea)))
 805                         return -EFAULT;
 806                 addr = parea.kernel_addr;
 807                 data = parea.process_addr;
 808                 copied = 0;
 809                 while (copied < parea.len) {
 810                         if (request == PTRACE_PEEKUSR_AREA)
 811                                 ret = peek_user_compat(child, addr, data);
 812                         else {
 813                                 __u32 utmp;
 814                                 if (get_user(utmp,
 815                                              (__u32 __force __user *) data))
 816                                         return -EFAULT;
 817                                 ret = poke_user_compat(child, addr, utmp);
 818                         }
 819                         if (ret)
 820                                 return ret;
 821                         addr += sizeof(unsigned int);
 822                         data += sizeof(unsigned int);
 823                         copied += sizeof(unsigned int);
 824                 }
 825                 return 0;
 826         case PTRACE_GET_LAST_BREAK:
 827                 return put_user(child->thread.last_break, (unsigned int __user *)data);
 828         }
 829         return compat_ptrace_request(child, request, addr, data);
 830 }
 831 #endif
 832
 833 /*
 834  * user_regset definitions.
 835  */
 836
 837 static int s390_regs_get(struct task_struct *target,
 838                          const struct user_regset *regset,
 839                          struct membuf to)
 840 {
 841         unsigned pos;
 842         if (target == current)
 843                 save_access_regs(target->thread.acrs);
 844
 845         for (pos = 0; pos < sizeof(s390_regs); pos += sizeof(long))
 846                 membuf_store(&to, __peek_user(target, pos));
 847         return 0;
 848 }
 849
 850 static int s390_regs_set(struct task_struct *target,
 851                          const struct user_regset *regset,
 852                          unsigned int pos, unsigned int count,
 853                          const void *kbuf, const void __user *ubuf)
 854 {
 855         int rc = 0;
 856
 857         if (target == current)
 858                 save_access_regs(target->thread.acrs);
 859
 860         if (kbuf) {
 861                 const unsigned long *k = kbuf;
 862                 while (count > 0 && !rc) {
 863                         rc = __poke_user(target, pos, *k++);
 864                         count -= sizeof(*k);
 865                         pos += sizeof(*k);
 866                 }
 867         } else {
 868                 const unsigned long  __user *u = ubuf;
 869                 while (count > 0 && !rc) {
 870                         unsigned long word;
 871                         rc = __get_user(word, u++);
 872                         if (rc)
 873                                 break;
 874                         rc = __poke_user(target, pos, word);
 875                         count -= sizeof(*u);
 876                         pos += sizeof(*u);
 877                 }
 878         }
 879
 880         if (rc == 0 && target == current)
 881                 restore_access_regs(target->thread.acrs);
 882
 883         return rc;
 884 }
 885
 886 static int s390_fpregs_get(struct task_struct *target,
 887                            const struct user_regset *regset,
 888                            struct membuf to)
 889 {
 890         _s390_fp_regs fp_regs;
 891
 892         if (target == current)
 893                 save_fpu_regs();
 894
 895         fp_regs.fpc = target->thread.fpu.fpc;
 896         fpregs_store(&fp_regs, &target->thread.fpu);
 897
 898         return membuf_write(&to, &fp_regs, sizeof(fp_regs));
 899 }
 900
 901 static int s390_fpregs_set(struct task_struct *target,
 902                            const struct user_regset *regset, unsigned int pos,
 903                            unsigned int count, const void *kbuf,
 904                            const void __user *ubuf)
 905 {
 906         int rc = 0;
 907         freg_t fprs[__NUM_FPRS];
 908
 909         save_fpu_regs();
 910         if (MACHINE_HAS_VX)
 911                 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
 912         else
 913                 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
 914
 915         /* If setting FPC, must validate it first. */
 916         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 917                 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
 918                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
 919                                         0, offsetof(s390_fp_regs, fprs));
 920                 if (rc)
 921                         return rc;
 922                 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
 923                         return -EINVAL;
 924                 target->thread.fpu.fpc = ufpc[0];
 925         }
 926
 927         if (rc == 0 && count > 0)
 928                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 929                                         fprs, offsetof(s390_fp_regs, fprs), -1);
 930         if (rc)
 931                 return rc;
 932
 933         if (MACHINE_HAS_VX)
 934                 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
 935         else
 936                 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
 937
 938         return rc;
 939 }
 940
 941 static int s390_last_break_get(struct task_struct *target,
 942                                const struct user_regset *regset,
 943                                struct membuf to)
 944 {
 945         return membuf_store(&to, target->thread.last_break);
 946 }
 947
 948 static int s390_last_break_set(struct task_struct *target,
 949                                const struct user_regset *regset,
 950                                unsigned int pos, unsigned int count,
 951                                const void *kbuf, const void __user *ubuf)
 952 {
 953         return 0;
 954 }
 955
 956 static int s390_tdb_get(struct task_struct *target,
 957                         const struct user_regset *regset,
 958                         struct membuf to)
 959 {
 960         struct pt_regs *regs = task_pt_regs(target);
 961         size_t size;
 962
 963         if (!(regs->int_code & 0x200))
 964                 return -ENODATA;
 965         size = sizeof(target->thread.trap_tdb.data);
 966         return membuf_write(&to, target->thread.trap_tdb.data, size);
 967 }
 968
 969 static int s390_tdb_set(struct task_struct *target,
 970                         const struct user_regset *regset,
 971                         unsigned int pos, unsigned int count,
 972                         const void *kbuf, const void __user *ubuf)
 973 {
 974         return 0;
 975 }
 976
 977 static int s390_vxrs_low_get(struct task_struct *target,
 978                              const struct user_regset *regset,
 979                              struct membuf to)
 980 {
 981         __u64 vxrs[__NUM_VXRS_LOW];
 982         int i;
 983
 984         if (!MACHINE_HAS_VX)
 985                 return -ENODEV;
 986         if (target == current)
 987                 save_fpu_regs();
 988         for (i = 0; i < __NUM_VXRS_LOW; i++)
 989                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
 990         return membuf_write(&to, vxrs, sizeof(vxrs));
 991 }
 992
 993 static int s390_vxrs_low_set(struct task_struct *target,
 994                              const struct user_regset *regset,
 995                              unsigned int pos, unsigned int count,
 996                              const void *kbuf, const void __user *ubuf)
 997 {
 998         __u64 vxrs[__NUM_VXRS_LOW];
 999         int i, rc;
1000
1001         if (!MACHINE_HAS_VX)
1002                 return -ENODEV;
1003         if (target == current)
1004                 save_fpu_regs();
1005
1006         for (i = 0; i < __NUM_VXRS_LOW; i++)
1007                 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1008
1009         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1010         if (rc == 0)
1011                 for (i = 0; i < __NUM_VXRS_LOW; i++)
1012                         *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1013
1014         return rc;
1015 }
1016
1017 static int s390_vxrs_high_get(struct task_struct *target,
1018                               const struct user_regset *regset,
1019                               struct membuf to)
1020 {
1021         if (!MACHINE_HAS_VX)
1022                 return -ENODEV;
1023         if (target == current)
1024                 save_fpu_regs();
1025         return membuf_write(&to, target->thread.fpu.vxrs + __NUM_VXRS_LOW,
1026                             __NUM_VXRS_HIGH * sizeof(__vector128));
1027 }
1028
1029 static int s390_vxrs_high_set(struct task_struct *target,
1030                               const struct user_regset *regset,
1031                               unsigned int pos, unsigned int count,
1032                               const void *kbuf, const void __user *ubuf)
1033 {
1034         int rc;
1035
1036         if (!MACHINE_HAS_VX)
1037                 return -ENODEV;
1038         if (target == current)
1039                 save_fpu_regs();
1040
1041         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1042                                 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1043         return rc;
1044 }
1045
1046 static int s390_system_call_get(struct task_struct *target,
1047                                 const struct user_regset *regset,
1048                                 struct membuf to)
1049 {
1050         return membuf_store(&to, target->thread.system_call);
1051 }
1052
1053 static int s390_system_call_set(struct task_struct *target,
1054                                 const struct user_regset *regset,
1055                                 unsigned int pos, unsigned int count,
1056                                 const void *kbuf, const void __user *ubuf)
1057 {
1058         unsigned int *data = &target->thread.system_call;
1059         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1060                                   data, 0, sizeof(unsigned int));
1061 }
1062
1063 static int s390_gs_cb_get(struct task_struct *target,
1064                           const struct user_regset *regset,
1065                           struct membuf to)
1066 {
1067         struct gs_cb *data = target->thread.gs_cb;
1068
1069         if (!MACHINE_HAS_GS)
1070                 return -ENODEV;
1071         if (!data)
1072                 return -ENODATA;
1073         if (target == current)
1074                 save_gs_cb(data);
1075         return membuf_write(&to, data, sizeof(struct gs_cb));
1076 }
1077
1078 static int s390_gs_cb_set(struct task_struct *target,
1079                           const struct user_regset *regset,
1080                           unsigned int pos, unsigned int count,
1081                           const void *kbuf, const void __user *ubuf)
1082 {
1083         struct gs_cb gs_cb = { }, *data = NULL;
1084         int rc;
1085
1086         if (!MACHINE_HAS_GS)
1087                 return -ENODEV;
1088         if (!target->thread.gs_cb) {
1089                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1090                 if (!data)
1091                         return -ENOMEM;
1092         }
1093         if (!target->thread.gs_cb)
1094                 gs_cb.gsd = 25;
1095         else if (target == current)
1096                 save_gs_cb(&gs_cb);
1097         else
1098                 gs_cb = *target->thread.gs_cb;
1099         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1100                                 &gs_cb, 0, sizeof(gs_cb));
1101         if (rc) {
1102                 kfree(data);
1103                 return -EFAULT;
1104         }
1105         preempt_disable();
1106         if (!target->thread.gs_cb)
1107                 target->thread.gs_cb = data;
1108         *target->thread.gs_cb = gs_cb;
1109         if (target == current) {
1110                 __ctl_set_bit(2, 4);
1111                 restore_gs_cb(target->thread.gs_cb);
1112         }
1113         preempt_enable();
1114         return rc;
1115 }
1116
1117 static int s390_gs_bc_get(struct task_struct *target,
1118                           const struct user_regset *regset,
1119                           struct membuf to)
1120 {
1121         struct gs_cb *data = target->thread.gs_bc_cb;
1122
1123         if (!MACHINE_HAS_GS)
1124                 return -ENODEV;
1125         if (!data)
1126                 return -ENODATA;
1127         return membuf_write(&to, data, sizeof(struct gs_cb));
1128 }
1129
1130 static int s390_gs_bc_set(struct task_struct *target,
1131                           const struct user_regset *regset,
1132                           unsigned int pos, unsigned int count,
1133                           const void *kbuf, const void __user *ubuf)
1134 {
1135         struct gs_cb *data = target->thread.gs_bc_cb;
1136
1137         if (!MACHINE_HAS_GS)
1138                 return -ENODEV;
1139         if (!data) {
1140                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1141                 if (!data)
1142                         return -ENOMEM;
1143                 target->thread.gs_bc_cb = data;
1144         }
1145         return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1146                                   data, 0, sizeof(struct gs_cb));
1147 }
1148
1149 static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1150 {
1151         return (cb->rca & 0x1f) == 0 &&
1152                 (cb->roa & 0xfff) == 0 &&
1153                 (cb->rla & 0xfff) == 0xfff &&
1154                 cb->s == 1 &&
1155                 cb->k == 1 &&
1156                 cb->h == 0 &&
1157                 cb->reserved1 == 0 &&
1158                 cb->ps == 1 &&
1159                 cb->qs == 0 &&
1160                 cb->pc == 1 &&
1161                 cb->qc == 0 &&
1162                 cb->reserved2 == 0 &&
1163                 cb->reserved3 == 0 &&
1164                 cb->reserved4 == 0 &&
1165                 cb->reserved5 == 0 &&
1166                 cb->reserved6 == 0 &&
1167                 cb->reserved7 == 0 &&
1168                 cb->reserved8 == 0 &&
1169                 cb->rla >= cb->roa &&
1170                 cb->rca >= cb->roa &&
1171                 cb->rca <= cb->rla+1 &&
1172                 cb->m < 3;
1173 }
1174
1175 static int s390_runtime_instr_get(struct task_struct *target,
1176                                 const struct user_regset *regset,
1177                                 struct membuf to)
1178 {
1179         struct runtime_instr_cb *data = target->thread.ri_cb;
1180
1181         if (!test_facility(64))
1182                 return -ENODEV;
1183         if (!data)
1184                 return -ENODATA;
1185
1186         return membuf_write(&to, data, sizeof(struct runtime_instr_cb));
1187 }
1188
1189 static int s390_runtime_instr_set(struct task_struct *target,
1190                                   const struct user_regset *regset,
1191                                   unsigned int pos, unsigned int count,
1192                                   const void *kbuf, const void __user *ubuf)
1193 {
1194         struct runtime_instr_cb ri_cb = { }, *data = NULL;
1195         int rc;
1196
1197         if (!test_facility(64))
1198                 return -ENODEV;
1199
1200         if (!target->thread.ri_cb) {
1201                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1202                 if (!data)
1203                         return -ENOMEM;
1204         }
1205
1206         if (target->thread.ri_cb) {
1207                 if (target == current)
1208                         store_runtime_instr_cb(&ri_cb);
1209                 else
1210                         ri_cb = *target->thread.ri_cb;
1211         }
1212
1213         rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1214                                 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1215         if (rc) {
1216                 kfree(data);
1217                 return -EFAULT;
1218         }
1219
1220         if (!is_ri_cb_valid(&ri_cb)) {
1221                 kfree(data);
1222                 return -EINVAL;
1223         }
1224         /*
1225          * Override access key in any case, since user space should
1226          * not be able to set it, nor should it care about it.
1227          */
1228         ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1229         preempt_disable();
1230         if (!target->thread.ri_cb)
1231                 target->thread.ri_cb = data;
1232         *target->thread.ri_cb = ri_cb;
1233         if (target == current)
1234                 load_runtime_instr_cb(target->thread.ri_cb);
1235         preempt_enable();
1236
1237         return 0;
1238 }
1239
1240 static const struct user_regset s390_regsets[] = {
1241         {
1242                 .core_note_type = NT_PRSTATUS,
1243                 .n = sizeof(s390_regs) / sizeof(long),
1244                 .size = sizeof(long),
1245                 .align = sizeof(long),
1246                 .regset_get = s390_regs_get,
1247                 .set = s390_regs_set,
1248         },
1249         {
1250                 .core_note_type = NT_PRFPREG,
1251                 .n = sizeof(s390_fp_regs) / sizeof(long),
1252                 .size = sizeof(long),
1253                 .align = sizeof(long),
1254                 .regset_get = s390_fpregs_get,
1255                 .set = s390_fpregs_set,
1256         },
1257         {
1258                 .core_note_type = NT_S390_SYSTEM_CALL,
1259                 .n = 1,
1260                 .size = sizeof(unsigned int),
1261                 .align = sizeof(unsigned int),
1262                 .regset_get = s390_system_call_get,
1263                 .set = s390_system_call_set,
1264         },
1265         {
1266                 .core_note_type = NT_S390_LAST_BREAK,
1267                 .n = 1,
1268                 .size = sizeof(long),
1269                 .align = sizeof(long),
1270                 .regset_get = s390_last_break_get,
1271                 .set = s390_last_break_set,
1272         },
1273         {
1274                 .core_note_type = NT_S390_TDB,
1275                 .n = 1,
1276                 .size = 256,
1277                 .align = 1,
1278                 .regset_get = s390_tdb_get,
1279                 .set = s390_tdb_set,
1280         },
1281         {
1282                 .core_note_type = NT_S390_VXRS_LOW,
1283                 .n = __NUM_VXRS_LOW,
1284                 .size = sizeof(__u64),
1285                 .align = sizeof(__u64),
1286                 .regset_get = s390_vxrs_low_get,
1287                 .set = s390_vxrs_low_set,
1288         },
1289         {
1290                 .core_note_type = NT_S390_VXRS_HIGH,
1291                 .n = __NUM_VXRS_HIGH,
1292                 .size = sizeof(__vector128),
1293                 .align = sizeof(__vector128),
1294                 .regset_get = s390_vxrs_high_get,
1295                 .set = s390_vxrs_high_set,
1296         },
1297         {
1298                 .core_note_type = NT_S390_GS_CB,
1299                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1300                 .size = sizeof(__u64),
1301                 .align = sizeof(__u64),
1302                 .regset_get = s390_gs_cb_get,
1303                 .set = s390_gs_cb_set,
1304         },
1305         {
1306                 .core_note_type = NT_S390_GS_BC,
1307                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1308                 .size = sizeof(__u64),
1309                 .align = sizeof(__u64),
1310                 .regset_get = s390_gs_bc_get,
1311                 .set = s390_gs_bc_set,
1312         },
1313         {
1314                 .core_note_type = NT_S390_RI_CB,
1315                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1316                 .size = sizeof(__u64),
1317                 .align = sizeof(__u64),
1318                 .regset_get = s390_runtime_instr_get,
1319                 .set = s390_runtime_instr_set,
1320         },
1321 };
1322
1323 static const struct user_regset_view user_s390_view = {
1324         .name = "s390x",
1325         .e_machine = EM_S390,
1326         .regsets = s390_regsets,
1327         .n = ARRAY_SIZE(s390_regsets)
1328 };
1329
1330 #ifdef CONFIG_COMPAT
1331 static int s390_compat_regs_get(struct task_struct *target,
1332                                 const struct user_regset *regset,
1333                                 struct membuf to)
1334 {
1335         unsigned n;
1336
1337         if (target == current)
1338                 save_access_regs(target->thread.acrs);
1339
1340         for (n = 0; n < sizeof(s390_compat_regs); n += sizeof(compat_ulong_t))
1341                 membuf_store(&to, __peek_user_compat(target, n));
1342         return 0;
1343 }
1344
1345 static int s390_compat_regs_set(struct task_struct *target,
1346                                 const struct user_regset *regset,
1347                                 unsigned int pos, unsigned int count,
1348                                 const void *kbuf, const void __user *ubuf)
1349 {
1350         int rc = 0;
1351
1352         if (target == current)
1353                 save_access_regs(target->thread.acrs);
1354
1355         if (kbuf) {
1356                 const compat_ulong_t *k = kbuf;
1357                 while (count > 0 && !rc) {
1358                         rc = __poke_user_compat(target, pos, *k++);
1359                         count -= sizeof(*k);
1360                         pos += sizeof(*k);
1361                 }
1362         } else {
1363                 const compat_ulong_t  __user *u = ubuf;
1364                 while (count > 0 && !rc) {
1365                         compat_ulong_t word;
1366                         rc = __get_user(word, u++);
1367                         if (rc)
1368                                 break;
1369                         rc = __poke_user_compat(target, pos, word);
1370                         count -= sizeof(*u);
1371                         pos += sizeof(*u);
1372                 }
1373         }
1374
1375         if (rc == 0 && target == current)
1376                 restore_access_regs(target->thread.acrs);
1377
1378         return rc;
1379 }
1380
1381 static int s390_compat_regs_high_get(struct task_struct *target,
1382                                      const struct user_regset *regset,
1383                                      struct membuf to)
1384 {
1385         compat_ulong_t *gprs_high;
1386         int i;
1387
1388         gprs_high = (compat_ulong_t *)task_pt_regs(target)->gprs;
1389         for (i = 0; i < NUM_GPRS; i++, gprs_high += 2)
1390                 membuf_store(&to, *gprs_high);
1391         return 0;
1392 }
1393
1394 static int s390_compat_regs_high_set(struct task_struct *target,
1395                                      const struct user_regset *regset,
1396                                      unsigned int pos, unsigned int count,
1397                                      const void *kbuf, const void __user *ubuf)
1398 {
1399         compat_ulong_t *gprs_high;
1400         int rc = 0;
1401
1402         gprs_high = (compat_ulong_t *)
1403                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1404         if (kbuf) {
1405                 const compat_ulong_t *k = kbuf;
1406                 while (count > 0) {
1407                         *gprs_high = *k++;
1408                         *gprs_high += 2;
1409                         count -= sizeof(*k);
1410                 }
1411         } else {
1412                 const compat_ulong_t  __user *u = ubuf;
1413                 while (count > 0 && !rc) {
1414                         unsigned long word;
1415                         rc = __get_user(word, u++);
1416                         if (rc)
1417                                 break;
1418                         *gprs_high = word;
1419                         *gprs_high += 2;
1420                         count -= sizeof(*u);
1421                 }
1422         }
1423
1424         return rc;
1425 }
1426
1427 static int s390_compat_last_break_get(struct task_struct *target,
1428                                       const struct user_regset *regset,
1429                                       struct membuf to)
1430 {
1431         compat_ulong_t last_break = target->thread.last_break;
1432
1433         return membuf_store(&to, (unsigned long)last_break);
1434 }
1435
1436 static int s390_compat_last_break_set(struct task_struct *target,
1437                                       const struct user_regset *regset,
1438                                       unsigned int pos, unsigned int count,
1439                                       const void *kbuf, const void __user *ubuf)
1440 {
1441         return 0;
1442 }
1443
1444 static const struct user_regset s390_compat_regsets[] = {
1445         {
1446                 .core_note_type = NT_PRSTATUS,
1447                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1448                 .size = sizeof(compat_long_t),
1449                 .align = sizeof(compat_long_t),
1450                 .regset_get = s390_compat_regs_get,
1451                 .set = s390_compat_regs_set,
1452         },
1453         {
1454                 .core_note_type = NT_PRFPREG,
1455                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1456                 .size = sizeof(compat_long_t),
1457                 .align = sizeof(compat_long_t),
1458                 .regset_get = s390_fpregs_get,
1459                 .set = s390_fpregs_set,
1460         },
1461         {
1462                 .core_note_type = NT_S390_SYSTEM_CALL,
1463                 .n = 1,
1464                 .size = sizeof(compat_uint_t),
1465                 .align = sizeof(compat_uint_t),
1466                 .regset_get = s390_system_call_get,
1467                 .set = s390_system_call_set,
1468         },
1469         {
1470                 .core_note_type = NT_S390_LAST_BREAK,
1471                 .n = 1,
1472                 .size = sizeof(long),
1473                 .align = sizeof(long),
1474                 .regset_get = s390_compat_last_break_get,
1475                 .set = s390_compat_last_break_set,
1476         },
1477         {
1478                 .core_note_type = NT_S390_TDB,
1479                 .n = 1,
1480                 .size = 256,
1481                 .align = 1,
1482                 .regset_get = s390_tdb_get,
1483                 .set = s390_tdb_set,
1484         },
1485         {
1486                 .core_note_type = NT_S390_VXRS_LOW,
1487                 .n = __NUM_VXRS_LOW,
1488                 .size = sizeof(__u64),
1489                 .align = sizeof(__u64),
1490                 .regset_get = s390_vxrs_low_get,
1491                 .set = s390_vxrs_low_set,
1492         },
1493         {
1494                 .core_note_type = NT_S390_VXRS_HIGH,
1495                 .n = __NUM_VXRS_HIGH,
1496                 .size = sizeof(__vector128),
1497                 .align = sizeof(__vector128),
1498                 .regset_get = s390_vxrs_high_get,
1499                 .set = s390_vxrs_high_set,
1500         },
1501         {
1502                 .core_note_type = NT_S390_HIGH_GPRS,
1503                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1504                 .size = sizeof(compat_long_t),
1505                 .align = sizeof(compat_long_t),
1506                 .regset_get = s390_compat_regs_high_get,
1507                 .set = s390_compat_regs_high_set,
1508         },
1509         {
1510                 .core_note_type = NT_S390_GS_CB,
1511                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1512                 .size = sizeof(__u64),
1513                 .align = sizeof(__u64),
1514                 .regset_get = s390_gs_cb_get,
1515                 .set = s390_gs_cb_set,
1516         },
1517         {
1518                 .core_note_type = NT_S390_GS_BC,
1519                 .n = sizeof(struct gs_cb) / sizeof(__u64),
1520                 .size = sizeof(__u64),
1521                 .align = sizeof(__u64),
1522                 .regset_get = s390_gs_bc_get,
1523                 .set = s390_gs_bc_set,
1524         },
1525         {
1526                 .core_note_type = NT_S390_RI_CB,
1527                 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1528                 .size = sizeof(__u64),
1529                 .align = sizeof(__u64),
1530                 .regset_get = s390_runtime_instr_get,
1531                 .set = s390_runtime_instr_set,
1532         },
1533 };
1534
1535 static const struct user_regset_view user_s390_compat_view = {
1536         .name = "s390",
1537         .e_machine = EM_S390,
1538         .regsets = s390_compat_regsets,
1539         .n = ARRAY_SIZE(s390_compat_regsets)
1540 };
1541 #endif
1542
1543 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1544 {
1545 #ifdef CONFIG_COMPAT
1546         if (test_tsk_thread_flag(task, TIF_31BIT))
1547                 return &user_s390_compat_view;
1548 #endif
1549         return &user_s390_view;
1550 }
1551
1552 static const char *gpr_names[NUM_GPRS] = {
1553         "r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1554         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1555 };
1556
1557 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1558 {
1559         if (offset >= NUM_GPRS)
1560                 return 0;
1561         return regs->gprs[offset];
1562 }
1563
1564 int regs_query_register_offset(const char *name)
1565 {
1566         unsigned long offset;
1567
1568         if (!name || *name != 'r')
1569                 return -EINVAL;
1570         if (kstrtoul(name + 1, 10, &offset))
1571                 return -EINVAL;
1572         if (offset >= NUM_GPRS)
1573                 return -EINVAL;
1574         return offset;
1575 }
1576
1577 const char *regs_query_register_name(unsigned int offset)
1578 {
1579         if (offset >= NUM_GPRS)
1580                 return NULL;
1581         return gpr_names[offset];
1582 }
1583
1584 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1585 {
1586         unsigned long ksp = kernel_stack_pointer(regs);
1587
1588         return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1589 }
1590
1591 /**
1592  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1593  * @regs:pt_regs which contains kernel stack pointer.
1594  * @n:stack entry number.
1595  *
1596  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1597  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1598  * this returns 0.
1599  */
1600 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1601 {
1602         unsigned long addr;
1603
1604         addr = kernel_stack_pointer(regs) + n * sizeof(long);
1605         if (!regs_within_kernel_stack(regs, addr))
1606                 return 0;
1607         return *(unsigned long *)addr;
1608 }