arch/m68k/kernel/signal.c

   1 /*
   2  *  linux/arch/m68k/kernel/signal.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file COPYING in the main directory of this archive
   8  * for more details.
   9  */
  10
  11 /*
  12  * Linux/m68k support by Hamish Macdonald
  13  *
  14  * 68060 fixes by Jesper Skov
  15  *
  16  * 1997-12-01  Modified for POSIX.1b signals by Andreas Schwab
  17  *
  18  * mathemu support by Roman Zippel
  19  *  (Note: fpstate in the signal context is completely ignored for the emulator
  20  *         and the internal floating point format is put on stack)
  21  */
  22
  23 /*
  24  * ++roman (07/09/96): implemented signal stacks (specially for tosemu on
  25  * Atari :-) Current limitation: Only one sigstack can be active at one time.
  26  * If a second signal with SA_ONSTACK set arrives while working on a sigstack,
  27  * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
  28  * signal handlers!
  29  */
  30
  31 #include <linux/sched.h>
  32 #include <linux/mm.h>
  33 #include <linux/kernel.h>
  34 #include <linux/signal.h>
  35 #include <linux/syscalls.h>
  36 #include <linux/errno.h>
  37 #include <linux/wait.h>
  38 #include <linux/ptrace.h>
  39 #include <linux/unistd.h>
  40 #include <linux/stddef.h>
  41 #include <linux/highuid.h>
  42 #include <linux/personality.h>
  43 #include <linux/tty.h>
  44 #include <linux/binfmts.h>
  45 #include <linux/module.h>
  46 #include <linux/tracehook.h>
  47
  48 #include <asm/setup.h>
  49 #include <asm/uaccess.h>
  50 #include <asm/pgtable.h>
  51 #include <asm/traps.h>
  52 #include <asm/ucontext.h>
  53 #include <asm/cacheflush.h>
  54
  55 #ifdef CONFIG_MMU
  56
  57 /*
  58  * Handle the slight differences in classic 68k and ColdFire trap frames.
  59  */
  60 #ifdef CONFIG_COLDFIRE
  61 #define FORMAT          4
  62 #define FMT4SIZE        0
  63 #else
  64 #define FORMAT          0
  65 #define FMT4SIZE        sizeof(((struct frame *)0)->un.fmt4)
  66 #endif
  67
  68 static const int frame_size_change[16] = {
  69   [1]   = -1, /* sizeof(((struct frame *)0)->un.fmt1), */
  70   [2]   = sizeof(((struct frame *)0)->un.fmt2),
  71   [3]   = sizeof(((struct frame *)0)->un.fmt3),
  72   [4]   = FMT4SIZE,
  73   [5]   = -1, /* sizeof(((struct frame *)0)->un.fmt5), */
  74   [6]   = -1, /* sizeof(((struct frame *)0)->un.fmt6), */
  75   [7]   = sizeof(((struct frame *)0)->un.fmt7),
  76   [8]   = -1, /* sizeof(((struct frame *)0)->un.fmt8), */
  77   [9]   = sizeof(((struct frame *)0)->un.fmt9),
  78   [10]  = sizeof(((struct frame *)0)->un.fmta),
  79   [11]  = sizeof(((struct frame *)0)->un.fmtb),
  80   [12]  = -1, /* sizeof(((struct frame *)0)->un.fmtc), */
  81   [13]  = -1, /* sizeof(((struct frame *)0)->un.fmtd), */
  82   [14]  = -1, /* sizeof(((struct frame *)0)->un.fmte), */
  83   [15]  = -1, /* sizeof(((struct frame *)0)->un.fmtf), */
  84 };
  85
  86 static inline int frame_extra_sizes(int f)
  87 {
  88         return frame_size_change[f];
  89 }
  90
  91 int handle_kernel_fault(struct pt_regs *regs)
  92 {
  93         const struct exception_table_entry *fixup;
  94         struct pt_regs *tregs;
  95
  96         /* Are we prepared to handle this kernel fault? */
  97         fixup = search_exception_tables(regs->pc);
  98         if (!fixup)
  99                 return 0;
 100
 101         /* Create a new four word stack frame, discarding the old one. */
 102         regs->stkadj = frame_extra_sizes(regs->format);
 103         tregs = (struct pt_regs *)((long)regs + regs->stkadj);
 104         tregs->vector = regs->vector;
 105         tregs->format = FORMAT;
 106         tregs->pc = fixup->fixup;
 107         tregs->sr = regs->sr;
 108
 109         return 1;
 110 }
 111
 112 void ptrace_signal_deliver(void)
 113 {
 114         struct pt_regs *regs = signal_pt_regs();
 115         if (regs->orig_d0 < 0)
 116                 return;
 117         switch (regs->d0) {
 118         case -ERESTARTNOHAND:
 119         case -ERESTARTSYS:
 120         case -ERESTARTNOINTR:
 121                 regs->d0 = regs->orig_d0;
 122                 regs->orig_d0 = -1;
 123                 regs->pc -= 2;
 124                 break;
 125         }
 126 }
 127
 128 static inline void push_cache (unsigned long vaddr)
 129 {
 130         /*
 131          * Using the old cache_push_v() was really a big waste.
 132          *
 133          * What we are trying to do is to flush 8 bytes to ram.
 134          * Flushing 2 cache lines of 16 bytes is much cheaper than
 135          * flushing 1 or 2 pages, as previously done in
 136          * cache_push_v().
 137          *                                                     Jes
 138          */
 139         if (CPU_IS_040) {
 140                 unsigned long temp;
 141
 142                 __asm__ __volatile__ (".chip 68040\n\t"
 143                                       "nop\n\t"
 144                                       "ptestr (%1)\n\t"
 145                                       "movec %%mmusr,%0\n\t"
 146                                       ".chip 68k"
 147                                       : "=r" (temp)
 148                                       : "a" (vaddr));
 149
 150                 temp &= PAGE_MASK;
 151                 temp |= vaddr & ~PAGE_MASK;
 152
 153                 __asm__ __volatile__ (".chip 68040\n\t"
 154                                       "nop\n\t"
 155                                       "cpushl %%bc,(%0)\n\t"
 156                                       ".chip 68k"
 157                                       : : "a" (temp));
 158         }
 159         else if (CPU_IS_060) {
 160                 unsigned long temp;
 161                 __asm__ __volatile__ (".chip 68060\n\t"
 162                                       "plpar (%0)\n\t"
 163                                       ".chip 68k"
 164                                       : "=a" (temp)
 165                                       : "0" (vaddr));
 166                 __asm__ __volatile__ (".chip 68060\n\t"
 167                                       "cpushl %%bc,(%0)\n\t"
 168                                       ".chip 68k"
 169                                       : : "a" (temp));
 170         } else if (!CPU_IS_COLDFIRE) {
 171                 /*
 172                  * 68030/68020 have no writeback cache;
 173                  * still need to clear icache.
 174                  * Note that vaddr is guaranteed to be long word aligned.
 175                  */
 176                 unsigned long temp;
 177                 asm volatile ("movec %%cacr,%0" : "=r" (temp));
 178                 temp += 4;
 179                 asm volatile ("movec %0,%%caar\n\t"
 180                               "movec %1,%%cacr"
 181                               : : "r" (vaddr), "r" (temp));
 182                 asm volatile ("movec %0,%%caar\n\t"
 183                               "movec %1,%%cacr"
 184                               : : "r" (vaddr + 4), "r" (temp));
 185         } else {
 186                 /* CPU_IS_COLDFIRE */
 187 #if defined(CONFIG_CACHE_COPYBACK)
 188                 flush_cf_dcache(0, DCACHE_MAX_ADDR);
 189 #endif
 190                 /* Invalidate instruction cache for the pushed bytes */
 191                 clear_cf_icache(vaddr, vaddr + 8);
 192         }
 193 }
 194
 195 static inline void adjustformat(struct pt_regs *regs)
 196 {
 197 }
 198
 199 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
 200 {
 201 }
 202
 203 #else /* CONFIG_MMU */
 204
 205 void ret_from_user_signal(void);
 206 void ret_from_user_rt_signal(void);
 207
 208 static inline int frame_extra_sizes(int f)
 209 {
 210         /* No frame size adjustments required on non-MMU CPUs */
 211         return 0;
 212 }
 213
 214 static inline void adjustformat(struct pt_regs *regs)
 215 {
 216         ((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
 217         /*
 218          * set format byte to make stack appear modulo 4, which it will
 219          * be when doing the rte
 220          */
 221         regs->format = 0x4;
 222 }
 223
 224 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
 225 {
 226         sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
 227 }
 228
 229 static inline void push_cache(unsigned long vaddr)
 230 {
 231 }
 232
 233 #endif /* CONFIG_MMU */
 234
 235 /*
 236  * Do a signal return; undo the signal stack.
 237  *
 238  * Keep the return code on the stack quadword aligned!
 239  * That makes the cache flush below easier.
 240  */
 241
 242 struct sigframe
 243 {
 244         char __user *pretcode;
 245         int sig;
 246         int code;
 247         struct sigcontext __user *psc;
 248         char retcode[8];
 249         unsigned long extramask[_NSIG_WORDS-1];
 250         struct sigcontext sc;
 251 };
 252
 253 struct rt_sigframe
 254 {
 255         char __user *pretcode;
 256         int sig;
 257         struct siginfo __user *pinfo;
 258         void __user *puc;
 259         char retcode[8];
 260         struct siginfo info;
 261         struct ucontext uc;
 262 };
 263
 264 #define FPCONTEXT_SIZE  216
 265 #define uc_fpstate      uc_filler[0]
 266 #define uc_formatvec    uc_filler[FPCONTEXT_SIZE/4]
 267 #define uc_extra        uc_filler[FPCONTEXT_SIZE/4+1]
 268
 269 #ifdef CONFIG_FPU
 270
 271 static unsigned char fpu_version;       /* version number of fpu, set by setup_frame */
 272
 273 static inline int restore_fpu_state(struct sigcontext *sc)
 274 {
 275         int err = 1;
 276
 277         if (FPU_IS_EMU) {
 278             /* restore registers */
 279             memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
 280             memcpy(current->thread.fp, sc->sc_fpregs, 24);
 281             return 0;
 282         }
 283
 284         if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
 285             /* Verify the frame format.  */
 286             if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
 287                  (sc->sc_fpstate[0] != fpu_version))
 288                 goto out;
 289             if (CPU_IS_020_OR_030) {
 290                 if (m68k_fputype & FPU_68881 &&
 291                     !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4))
 292                     goto out;
 293                 if (m68k_fputype & FPU_68882 &&
 294                     !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4))
 295                     goto out;
 296             } else if (CPU_IS_040) {
 297                 if (!(sc->sc_fpstate[1] == 0x00 ||
 298                       sc->sc_fpstate[1] == 0x28 ||
 299                       sc->sc_fpstate[1] == 0x60))
 300                     goto out;
 301             } else if (CPU_IS_060) {
 302                 if (!(sc->sc_fpstate[3] == 0x00 ||
 303                       sc->sc_fpstate[3] == 0x60 ||
 304                       sc->sc_fpstate[3] == 0xe0))
 305                     goto out;
 306             } else if (CPU_IS_COLDFIRE) {
 307                 if (!(sc->sc_fpstate[0] == 0x00 ||
 308                       sc->sc_fpstate[0] == 0x05 ||
 309                       sc->sc_fpstate[0] == 0xe5))
 310                     goto out;
 311             } else
 312                 goto out;
 313
 314             if (CPU_IS_COLDFIRE) {
 315                 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t"
 316                                   "fmovel %1,%%fpcr\n\t"
 317                                   "fmovel %2,%%fpsr\n\t"
 318                                   "fmovel %3,%%fpiar"
 319                                   : /* no outputs */
 320                                   : "m" (sc->sc_fpregs[0]),
 321                                     "m" (sc->sc_fpcntl[0]),
 322                                     "m" (sc->sc_fpcntl[1]),
 323                                     "m" (sc->sc_fpcntl[2]));
 324             } else {
 325                 __asm__ volatile (".chip 68k/68881\n\t"
 326                                   "fmovemx %0,%%fp0-%%fp1\n\t"
 327                                   "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
 328                                   ".chip 68k"
 329                                   : /* no outputs */
 330                                   : "m" (*sc->sc_fpregs),
 331                                     "m" (*sc->sc_fpcntl));
 332             }
 333         }
 334
 335         if (CPU_IS_COLDFIRE) {
 336                 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate));
 337         } else {
 338                 __asm__ volatile (".chip 68k/68881\n\t"
 339                                   "frestore %0\n\t"
 340                                   ".chip 68k"
 341                                   : : "m" (*sc->sc_fpstate));
 342         }
 343         err = 0;
 344
 345 out:
 346         return err;
 347 }
 348
 349 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
 350 {
 351         unsigned char fpstate[FPCONTEXT_SIZE];
 352         int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
 353         fpregset_t fpregs;
 354         int err = 1;
 355
 356         if (FPU_IS_EMU) {
 357                 /* restore fpu control register */
 358                 if (__copy_from_user(current->thread.fpcntl,
 359                                 uc->uc_mcontext.fpregs.f_fpcntl, 12))
 360                         goto out;
 361                 /* restore all other fpu register */
 362                 if (__copy_from_user(current->thread.fp,
 363                                 uc->uc_mcontext.fpregs.f_fpregs, 96))
 364                         goto out;
 365                 return 0;
 366         }
 367
 368         if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
 369                 goto out;
 370         if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
 371                 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
 372                         context_size = fpstate[1];
 373                 /* Verify the frame format.  */
 374                 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
 375                      (fpstate[0] != fpu_version))
 376                         goto out;
 377                 if (CPU_IS_020_OR_030) {
 378                         if (m68k_fputype & FPU_68881 &&
 379                             !(context_size == 0x18 || context_size == 0xb4))
 380                                 goto out;
 381                         if (m68k_fputype & FPU_68882 &&
 382                             !(context_size == 0x38 || context_size == 0xd4))
 383                                 goto out;
 384                 } else if (CPU_IS_040) {
 385                         if (!(context_size == 0x00 ||
 386                               context_size == 0x28 ||
 387                               context_size == 0x60))
 388                                 goto out;
 389                 } else if (CPU_IS_060) {
 390                         if (!(fpstate[3] == 0x00 ||
 391                               fpstate[3] == 0x60 ||
 392                               fpstate[3] == 0xe0))
 393                                 goto out;
 394                 } else if (CPU_IS_COLDFIRE) {
 395                         if (!(fpstate[3] == 0x00 ||
 396                               fpstate[3] == 0x05 ||
 397                               fpstate[3] == 0xe5))
 398                                 goto out;
 399                 } else
 400                         goto out;
 401                 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
 402                                      sizeof(fpregs)))
 403                         goto out;
 404
 405                 if (CPU_IS_COLDFIRE) {
 406                         __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t"
 407                                           "fmovel %1,%%fpcr\n\t"
 408                                           "fmovel %2,%%fpsr\n\t"
 409                                           "fmovel %3,%%fpiar"
 410                                           : /* no outputs */
 411                                           : "m" (fpregs.f_fpregs[0]),
 412                                             "m" (fpregs.f_fpcntl[0]),
 413                                             "m" (fpregs.f_fpcntl[1]),
 414                                             "m" (fpregs.f_fpcntl[2]));
 415                 } else {
 416                         __asm__ volatile (".chip 68k/68881\n\t"
 417                                           "fmovemx %0,%%fp0-%%fp7\n\t"
 418                                           "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
 419                                           ".chip 68k"
 420                                           : /* no outputs */
 421                                           : "m" (*fpregs.f_fpregs),
 422                                             "m" (*fpregs.f_fpcntl));
 423                 }
 424         }
 425         if (context_size &&
 426             __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
 427                              context_size))
 428                 goto out;
 429
 430         if (CPU_IS_COLDFIRE) {
 431                 __asm__ volatile ("frestore %0" : : "m" (*fpstate));
 432         } else {
 433                 __asm__ volatile (".chip 68k/68881\n\t"
 434                                   "frestore %0\n\t"
 435                                   ".chip 68k"
 436                                   : : "m" (*fpstate));
 437         }
 438         err = 0;
 439
 440 out:
 441         return err;
 442 }
 443
 444 /*
 445  * Set up a signal frame.
 446  */
 447 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
 448 {
 449         if (FPU_IS_EMU) {
 450                 /* save registers */
 451                 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
 452                 memcpy(sc->sc_fpregs, current->thread.fp, 24);
 453                 return;
 454         }
 455
 456         if (CPU_IS_COLDFIRE) {
 457                 __asm__ volatile ("fsave %0"
 458                                   : : "m" (*sc->sc_fpstate) : "memory");
 459         } else {
 460                 __asm__ volatile (".chip 68k/68881\n\t"
 461                                   "fsave %0\n\t"
 462                                   ".chip 68k"
 463                                   : : "m" (*sc->sc_fpstate) : "memory");
 464         }
 465
 466         if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
 467                 fpu_version = sc->sc_fpstate[0];
 468                 if (CPU_IS_020_OR_030 &&
 469                     regs->vector >= (VEC_FPBRUC * 4) &&
 470                     regs->vector <= (VEC_FPNAN * 4)) {
 471                         /* Clear pending exception in 68882 idle frame */
 472                         if (*(unsigned short *) sc->sc_fpstate == 0x1f38)
 473                                 sc->sc_fpstate[0x38] |= 1 << 3;
 474                 }
 475
 476                 if (CPU_IS_COLDFIRE) {
 477                         __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t"
 478                                           "fmovel %%fpcr,%1\n\t"
 479                                           "fmovel %%fpsr,%2\n\t"
 480                                           "fmovel %%fpiar,%3"
 481                                           : "=m" (sc->sc_fpregs[0]),
 482                                             "=m" (sc->sc_fpcntl[0]),
 483                                             "=m" (sc->sc_fpcntl[1]),
 484                                             "=m" (sc->sc_fpcntl[2])
 485                                           : /* no inputs */
 486                                           : "memory");
 487                 } else {
 488                         __asm__ volatile (".chip 68k/68881\n\t"
 489                                           "fmovemx %%fp0-%%fp1,%0\n\t"
 490                                           "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
 491                                           ".chip 68k"
 492                                           : "=m" (*sc->sc_fpregs),
 493                                             "=m" (*sc->sc_fpcntl)
 494                                           : /* no inputs */
 495                                           : "memory");
 496                 }
 497         }
 498 }
 499
 500 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
 501 {
 502         unsigned char fpstate[FPCONTEXT_SIZE];
 503         int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
 504         int err = 0;
 505
 506         if (FPU_IS_EMU) {
 507                 /* save fpu control register */
 508                 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl,
 509                                 current->thread.fpcntl, 12);
 510                 /* save all other fpu register */
 511                 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
 512                                 current->thread.fp, 96);
 513                 return err;
 514         }
 515
 516         if (CPU_IS_COLDFIRE) {
 517                 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory");
 518         } else {
 519                 __asm__ volatile (".chip 68k/68881\n\t"
 520                                   "fsave %0\n\t"
 521                                   ".chip 68k"
 522                                   : : "m" (*fpstate) : "memory");
 523         }
 524
 525         err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate);
 526         if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
 527                 fpregset_t fpregs;
 528                 if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
 529                         context_size = fpstate[1];
 530                 fpu_version = fpstate[0];
 531                 if (CPU_IS_020_OR_030 &&
 532                     regs->vector >= (VEC_FPBRUC * 4) &&
 533                     regs->vector <= (VEC_FPNAN * 4)) {
 534                         /* Clear pending exception in 68882 idle frame */
 535                         if (*(unsigned short *) fpstate == 0x1f38)
 536                                 fpstate[0x38] |= 1 << 3;
 537                 }
 538                 if (CPU_IS_COLDFIRE) {
 539                         __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t"
 540                                           "fmovel %%fpcr,%1\n\t"
 541                                           "fmovel %%fpsr,%2\n\t"
 542                                           "fmovel %%fpiar,%3"
 543                                           : "=m" (fpregs.f_fpregs[0]),
 544                                             "=m" (fpregs.f_fpcntl[0]),
 545                                             "=m" (fpregs.f_fpcntl[1]),
 546                                             "=m" (fpregs.f_fpcntl[2])
 547                                           : /* no inputs */
 548                                           : "memory");
 549                 } else {
 550                         __asm__ volatile (".chip 68k/68881\n\t"
 551                                           "fmovemx %%fp0-%%fp7,%0\n\t"
 552                                           "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
 553                                           ".chip 68k"
 554                                           : "=m" (*fpregs.f_fpregs),
 555                                             "=m" (*fpregs.f_fpcntl)
 556                                           : /* no inputs */
 557                                           : "memory");
 558                 }
 559                 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
 560                                     sizeof(fpregs));
 561         }
 562         if (context_size)
 563                 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4,
 564                                     context_size);
 565         return err;
 566 }
 567
 568 #else /* CONFIG_FPU */
 569
 570 /*
 571  * For the case with no FPU configured these all do nothing.
 572  */
 573 static inline int restore_fpu_state(struct sigcontext *sc)
 574 {
 575         return 0;
 576 }
 577
 578 static inline int rt_restore_fpu_state(struct ucontext __user *uc)
 579 {
 580         return 0;
 581 }
 582
 583 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
 584 {
 585 }
 586
 587 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
 588 {
 589         return 0;
 590 }
 591
 592 #endif /* CONFIG_FPU */
 593
 594 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec,
 595                                void __user *fp)
 596 {
 597         int fsize = frame_extra_sizes(formatvec >> 12);
 598         if (fsize < 0) {
 599                 /*
 600                  * user process trying to return with weird frame format
 601                  */
 602 #ifdef DEBUG
 603                 printk("user process returning with weird frame format\n");
 604 #endif
 605                 return 1;
 606         }
 607         if (!fsize) {
 608                 regs->format = formatvec >> 12;
 609                 regs->vector = formatvec & 0xfff;
 610         } else {
 611                 struct switch_stack *sw = (struct switch_stack *)regs - 1;
 612                 unsigned long buf[fsize / 2]; /* yes, twice as much */
 613
 614                 /* that'll make sure that expansion won't crap over data */
 615                 if (copy_from_user(buf + fsize / 4, fp, fsize))
 616                         return 1;
 617
 618                 /* point of no return */
 619                 regs->format = formatvec >> 12;
 620                 regs->vector = formatvec & 0xfff;
 621 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
 622                 __asm__ __volatile__ (
 623 #ifdef CONFIG_COLDFIRE
 624                          "   movel %0,%/sp\n\t"
 625                          "   bra ret_from_signal\n"
 626 #else
 627                          "   movel %0,%/a0\n\t"
 628                          "   subl %1,%/a0\n\t"     /* make room on stack */
 629                          "   movel %/a0,%/sp\n\t"  /* set stack pointer */
 630                          /* move switch_stack and pt_regs */
 631                          "1: movel %0@+,%/a0@+\n\t"
 632                          "   dbra %2,1b\n\t"
 633                          "   lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */
 634                          "   lsrl  #2,%1\n\t"
 635                          "   subql #1,%1\n\t"
 636                          /* copy to the gap we'd made */
 637                          "2: movel %4@+,%/a0@+\n\t"
 638                          "   dbra %1,2b\n\t"
 639                          "   bral ret_from_signal\n"
 640 #endif
 641                          : /* no outputs, it doesn't ever return */
 642                          : "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
 643                            "n" (frame_offset), "a" (buf + fsize/4)
 644                          : "a0");
 645 #undef frame_offset
 646         }
 647         return 0;
 648 }
 649
 650 static inline int
 651 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp)
 652 {
 653         int formatvec;
 654         struct sigcontext context;
 655         int err = 0;
 656
 657         /* Always make any pending restarted system calls return -EINTR */
 658         current->restart_block.fn = do_no_restart_syscall;
 659
 660         /* get previous context */
 661         if (copy_from_user(&context, usc, sizeof(context)))
 662                 goto badframe;
 663
 664         /* restore passed registers */
 665         regs->d0 = context.sc_d0;
 666         regs->d1 = context.sc_d1;
 667         regs->a0 = context.sc_a0;
 668         regs->a1 = context.sc_a1;
 669         regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
 670         regs->pc = context.sc_pc;
 671         regs->orig_d0 = -1;             /* disable syscall checks */
 672         wrusp(context.sc_usp);
 673         formatvec = context.sc_formatvec;
 674
 675         err = restore_fpu_state(&context);
 676
 677         if (err || mangle_kernel_stack(regs, formatvec, fp))
 678                 goto badframe;
 679
 680         return 0;
 681
 682 badframe:
 683         return 1;
 684 }
 685
 686 static inline int
 687 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
 688                     struct ucontext __user *uc)
 689 {
 690         int temp;
 691         greg_t __user *gregs = uc->uc_mcontext.gregs;
 692         unsigned long usp;
 693         int err;
 694
 695         /* Always make any pending restarted system calls return -EINTR */
 696         current->restart_block.fn = do_no_restart_syscall;
 697
 698         err = __get_user(temp, &uc->uc_mcontext.version);
 699         if (temp != MCONTEXT_VERSION)
 700                 goto badframe;
 701         /* restore passed registers */
 702         err |= __get_user(regs->d0, &gregs[0]);
 703         err |= __get_user(regs->d1, &gregs[1]);
 704         err |= __get_user(regs->d2, &gregs[2]);
 705         err |= __get_user(regs->d3, &gregs[3]);
 706         err |= __get_user(regs->d4, &gregs[4]);
 707         err |= __get_user(regs->d5, &gregs[5]);
 708         err |= __get_user(sw->d6, &gregs[6]);
 709         err |= __get_user(sw->d7, &gregs[7]);
 710         err |= __get_user(regs->a0, &gregs[8]);
 711         err |= __get_user(regs->a1, &gregs[9]);
 712         err |= __get_user(regs->a2, &gregs[10]);
 713         err |= __get_user(sw->a3, &gregs[11]);
 714         err |= __get_user(sw->a4, &gregs[12]);
 715         err |= __get_user(sw->a5, &gregs[13]);
 716         err |= __get_user(sw->a6, &gregs[14]);
 717         err |= __get_user(usp, &gregs[15]);
 718         wrusp(usp);
 719         err |= __get_user(regs->pc, &gregs[16]);
 720         err |= __get_user(temp, &gregs[17]);
 721         regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
 722         regs->orig_d0 = -1;             /* disable syscall checks */
 723         err |= __get_user(temp, &uc->uc_formatvec);
 724
 725         err |= rt_restore_fpu_state(uc);
 726         err |= restore_altstack(&uc->uc_stack);
 727
 728         if (err)
 729                 goto badframe;
 730
 731         if (mangle_kernel_stack(regs, temp, &uc->uc_extra))
 732                 goto badframe;
 733
 734         return 0;
 735
 736 badframe:
 737         return 1;
 738 }
 739
 740 asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
 741 {
 742         unsigned long usp = rdusp();
 743         struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
 744         sigset_t set;
 745
 746         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 747                 goto badframe;
 748         if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
 749             (_NSIG_WORDS > 1 &&
 750              __copy_from_user(&set.sig[1], &frame->extramask,
 751                               sizeof(frame->extramask))))
 752                 goto badframe;
 753
 754         set_current_blocked(&set);
 755
 756         if (restore_sigcontext(regs, &frame->sc, frame + 1))
 757                 goto badframe;
 758         return regs->d0;
 759
 760 badframe:
 761         force_sig(SIGSEGV, current);
 762         return 0;
 763 }
 764
 765 asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
 766 {
 767         unsigned long usp = rdusp();
 768         struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4);
 769         sigset_t set;
 770
 771         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 772                 goto badframe;
 773         if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 774                 goto badframe;
 775
 776         set_current_blocked(&set);
 777
 778         if (rt_restore_ucontext(regs, sw, &frame->uc))
 779                 goto badframe;
 780         return regs->d0;
 781
 782 badframe:
 783         force_sig(SIGSEGV, current);
 784         return 0;
 785 }
 786
 787 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
 788                              unsigned long mask)
 789 {
 790         sc->sc_mask = mask;
 791         sc->sc_usp = rdusp();
 792         sc->sc_d0 = regs->d0;
 793         sc->sc_d1 = regs->d1;
 794         sc->sc_a0 = regs->a0;
 795         sc->sc_a1 = regs->a1;
 796         sc->sc_sr = regs->sr;
 797         sc->sc_pc = regs->pc;
 798         sc->sc_formatvec = regs->format << 12 | regs->vector;
 799         save_a5_state(sc, regs);
 800         save_fpu_state(sc, regs);
 801 }
 802
 803 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
 804 {
 805         struct switch_stack *sw = (struct switch_stack *)regs - 1;
 806         greg_t __user *gregs = uc->uc_mcontext.gregs;
 807         int err = 0;
 808
 809         err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
 810         err |= __put_user(regs->d0, &gregs[0]);
 811         err |= __put_user(regs->d1, &gregs[1]);
 812         err |= __put_user(regs->d2, &gregs[2]);
 813         err |= __put_user(regs->d3, &gregs[3]);
 814         err |= __put_user(regs->d4, &gregs[4]);
 815         err |= __put_user(regs->d5, &gregs[5]);
 816         err |= __put_user(sw->d6, &gregs[6]);
 817         err |= __put_user(sw->d7, &gregs[7]);
 818         err |= __put_user(regs->a0, &gregs[8]);
 819         err |= __put_user(regs->a1, &gregs[9]);
 820         err |= __put_user(regs->a2, &gregs[10]);
 821         err |= __put_user(sw->a3, &gregs[11]);
 822         err |= __put_user(sw->a4, &gregs[12]);
 823         err |= __put_user(sw->a5, &gregs[13]);
 824         err |= __put_user(sw->a6, &gregs[14]);
 825         err |= __put_user(rdusp(), &gregs[15]);
 826         err |= __put_user(regs->pc, &gregs[16]);
 827         err |= __put_user(regs->sr, &gregs[17]);
 828         err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec);
 829         err |= rt_save_fpu_state(uc, regs);
 830         return err;
 831 }
 832
 833 static inline void __user *
 834 get_sigframe(struct ksignal *ksig, size_t frame_size)
 835 {
 836         unsigned long usp = sigsp(rdusp(), ksig);
 837
 838         return (void __user *)((usp - frame_size) & -8UL);
 839 }
 840
 841 static int setup_frame(struct ksignal *ksig, sigset_t *set,
 842                         struct pt_regs *regs)
 843 {
 844         struct sigframe __user *frame;
 845         int fsize = frame_extra_sizes(regs->format);
 846         struct sigcontext context;
 847         int err = 0, sig = ksig->sig;
 848
 849         if (fsize < 0) {
 850 #ifdef DEBUG
 851                 printk ("setup_frame: Unknown frame format %#x\n",
 852                         regs->format);
 853 #endif
 854                 return -EFAULT;
 855         }
 856
 857         frame = get_sigframe(ksig, sizeof(*frame) + fsize);
 858
 859         if (fsize)
 860                 err |= copy_to_user (frame + 1, regs + 1, fsize);
 861
 862         err |= __put_user(sig, &frame->sig);
 863
 864         err |= __put_user(regs->vector, &frame->code);
 865         err |= __put_user(&frame->sc, &frame->psc);
 866
 867         if (_NSIG_WORDS > 1)
 868                 err |= copy_to_user(frame->extramask, &set->sig[1],
 869                                     sizeof(frame->extramask));
 870
 871         setup_sigcontext(&context, regs, set->sig[0]);
 872         err |= copy_to_user (&frame->sc, &context, sizeof(context));
 873
 874         /* Set up to return from userspace.  */
 875 #ifdef CONFIG_MMU
 876         err |= __put_user(frame->retcode, &frame->pretcode);
 877         /* moveq #,d0; trap #0 */
 878         err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
 879                           (long __user *)(frame->retcode));
 880 #else
 881         err |= __put_user((void *) ret_from_user_signal, &frame->pretcode);
 882 #endif
 883
 884         if (err)
 885                 return -EFAULT;
 886
 887         push_cache ((unsigned long) &frame->retcode);
 888
 889         /*
 890          * Set up registers for signal handler.  All the state we are about
 891          * to destroy is successfully copied to sigframe.
 892          */
 893         wrusp ((unsigned long) frame);
 894         regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
 895         adjustformat(regs);
 896
 897         /*
 898          * This is subtle; if we build more than one sigframe, all but the
 899          * first one will see frame format 0 and have fsize == 0, so we won't
 900          * screw stkadj.
 901          */
 902         if (fsize)
 903                 regs->stkadj = fsize;
 904
 905         /* Prepare to skip over the extra stuff in the exception frame.  */
 906         if (regs->stkadj) {
 907                 struct pt_regs *tregs =
 908                         (struct pt_regs *)((ulong)regs + regs->stkadj);
 909 #ifdef DEBUG
 910                 printk("Performing stackadjust=%04x\n", regs->stkadj);
 911 #endif
 912                 /* This must be copied with decreasing addresses to
 913                    handle overlaps.  */
 914                 tregs->vector = 0;
 915                 tregs->format = 0;
 916                 tregs->pc = regs->pc;
 917                 tregs->sr = regs->sr;
 918         }
 919         return 0;
 920 }
 921
 922 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 923                            struct pt_regs *regs)
 924 {
 925         struct rt_sigframe __user *frame;
 926         int fsize = frame_extra_sizes(regs->format);
 927         int err = 0, sig = ksig->sig;
 928
 929         if (fsize < 0) {
 930 #ifdef DEBUG
 931                 printk ("setup_frame: Unknown frame format %#x\n",
 932                         regs->format);
 933 #endif
 934                 return -EFAULT;
 935         }
 936
 937         frame = get_sigframe(ksig, sizeof(*frame));
 938
 939         if (fsize)
 940                 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize);
 941
 942         err |= __put_user(sig, &frame->sig);
 943         err |= __put_user(&frame->info, &frame->pinfo);
 944         err |= __put_user(&frame->uc, &frame->puc);
 945         err |= copy_siginfo_to_user(&frame->info, &ksig->info);
 946
 947         /* Create the ucontext.  */
 948         err |= __put_user(0, &frame->uc.uc_flags);
 949         err |= __put_user(NULL, &frame->uc.uc_link);
 950         err |= __save_altstack(&frame->uc.uc_stack, rdusp());
 951         err |= rt_setup_ucontext(&frame->uc, regs);
 952         err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
 953
 954         /* Set up to return from userspace.  */
 955 #ifdef CONFIG_MMU
 956         err |= __put_user(frame->retcode, &frame->pretcode);
 957 #ifdef __mcoldfire__
 958         /* movel #__NR_rt_sigreturn,d0; trap #0 */
 959         err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0));
 960         err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16),
 961                           (long __user *)(frame->retcode + 4));
 962 #else
 963         /* moveq #,d0; notb d0; trap #0 */
 964         err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
 965                           (long __user *)(frame->retcode + 0));
 966         err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4));
 967 #endif
 968 #else
 969         err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode);
 970 #endif /* CONFIG_MMU */
 971
 972         if (err)
 973                 return -EFAULT;
 974
 975         push_cache ((unsigned long) &frame->retcode);
 976
 977         /*
 978          * Set up registers for signal handler.  All the state we are about
 979          * to destroy is successfully copied to sigframe.
 980          */
 981         wrusp ((unsigned long) frame);
 982         regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
 983         adjustformat(regs);
 984
 985         /*
 986          * This is subtle; if we build more than one sigframe, all but the
 987          * first one will see frame format 0 and have fsize == 0, so we won't
 988          * screw stkadj.
 989          */
 990         if (fsize)
 991                 regs->stkadj = fsize;
 992
 993         /* Prepare to skip over the extra stuff in the exception frame.  */
 994         if (regs->stkadj) {
 995                 struct pt_regs *tregs =
 996                         (struct pt_regs *)((ulong)regs + regs->stkadj);
 997 #ifdef DEBUG
 998                 printk("Performing stackadjust=%04x\n", regs->stkadj);
 999 #endif
1000                 /* This must be copied with decreasing addresses to
1001                    handle overlaps.  */
1002                 tregs->vector = 0;
1003                 tregs->format = 0;
1004                 tregs->pc = regs->pc;
1005                 tregs->sr = regs->sr;
1006         }
1007         return 0;
1008 }
1009
1010 static inline void
1011 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
1012 {
1013         switch (regs->d0) {
1014         case -ERESTARTNOHAND:
1015                 if (!has_handler)
1016                         goto do_restart;
1017                 regs->d0 = -EINTR;
1018                 break;
1019
1020         case -ERESTART_RESTARTBLOCK:
1021                 if (!has_handler) {
1022                         regs->d0 = __NR_restart_syscall;
1023                         regs->pc -= 2;
1024                         break;
1025                 }
1026                 regs->d0 = -EINTR;
1027                 break;
1028
1029         case -ERESTARTSYS:
1030                 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
1031                         regs->d0 = -EINTR;
1032                         break;
1033                 }
1034         /* fallthrough */
1035         case -ERESTARTNOINTR:
1036         do_restart:
1037                 regs->d0 = regs->orig_d0;
1038                 regs->pc -= 2;
1039                 break;
1040         }
1041 }
1042
1043 /*
1044  * OK, we're invoking a handler
1045  */
1046 static void
1047 handle_signal(struct ksignal *ksig, struct pt_regs *regs)
1048 {
1049         sigset_t *oldset = sigmask_to_save();
1050         int err;
1051         /* are we from a system call? */
1052         if (regs->orig_d0 >= 0)
1053                 /* If so, check system call restarting.. */
1054                 handle_restart(regs, &ksig->ka, 1);
1055
1056         /* set up the stack frame */
1057         if (ksig->ka.sa.sa_flags & SA_SIGINFO)
1058                 err = setup_rt_frame(ksig, oldset, regs);
1059         else
1060                 err = setup_frame(ksig, oldset, regs);
1061
1062         signal_setup_done(err, ksig, 0);
1063
1064         if (test_thread_flag(TIF_DELAYED_TRACE)) {
1065                 regs->sr &= ~0x8000;
1066                 send_sig(SIGTRAP, current, 1);
1067         }
1068 }
1069
1070 /*
1071  * Note that 'init' is a special process: it doesn't get signals it doesn't
1072  * want to handle. Thus you cannot kill init even with a SIGKILL even by
1073  * mistake.
1074  */
1075 static void do_signal(struct pt_regs *regs)
1076 {
1077         struct ksignal ksig;
1078
1079         current->thread.esp0 = (unsigned long) regs;
1080
1081         if (get_signal(&ksig)) {
1082                 /* Whee!  Actually deliver the signal.  */
1083                 handle_signal(&ksig, regs);
1084                 return;
1085         }
1086
1087         /* Did we come from a system call? */
1088         if (regs->orig_d0 >= 0)
1089                 /* Restart the system call - no handlers present */
1090                 handle_restart(regs, NULL, 0);
1091
1092         /* If there's no signal to deliver, we just restore the saved mask.  */
1093         restore_saved_sigmask();
1094 }
1095
1096 void do_notify_resume(struct pt_regs *regs)
1097 {
1098         if (test_thread_flag(TIF_SIGPENDING))
1099                 do_signal(regs);
1100
1101         if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
1102                 tracehook_notify_resume(regs);
1103 }