arch/m68knommu/kernel/signal.c

   1 /*
   2  *  linux/arch/m68knommu/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/tty.h>
  43 #include <linux/personality.h>
  44 #include <linux/binfmts.h>
  45
  46 #include <asm/setup.h>
  47 #include <asm/uaccess.h>
  48 #include <asm/pgtable.h>
  49 #include <asm/traps.h>
  50 #include <asm/ucontext.h>
  51
  52 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  53
  54 asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs);
  55
  56 /*
  57  * Atomically swap in the new signal mask, and wait for a signal.
  58  */
  59 asmlinkage int do_sigsuspend(struct pt_regs *regs)
  60 {
  61         old_sigset_t mask = regs->d3;
  62         sigset_t saveset;
  63
  64         mask &= _BLOCKABLE;
  65         spin_lock_irq(&current->sighand->siglock);
  66         saveset = current->blocked;
  67         siginitset(&current->blocked, mask);
  68         recalc_sigpending();
  69         spin_unlock_irq(&current->sighand->siglock);
  70
  71         regs->d0 = -EINTR;
  72         while (1) {
  73                 current->state = TASK_INTERRUPTIBLE;
  74                 schedule();
  75                 if (do_signal(&saveset, regs))
  76                         return -EINTR;
  77         }
  78 }
  79
  80 asmlinkage int
  81 do_rt_sigsuspend(struct pt_regs *regs)
  82 {
  83         sigset_t *unewset = (sigset_t *)regs->d1;
  84         size_t sigsetsize = (size_t)regs->d2;
  85         sigset_t saveset, newset;
  86
  87         /* XXX: Don't preclude handling different sized sigset_t's.  */
  88         if (sigsetsize != sizeof(sigset_t))
  89                 return -EINVAL;
  90
  91         if (copy_from_user(&newset, unewset, sizeof(newset)))
  92                 return -EFAULT;
  93         sigdelsetmask(&newset, ~_BLOCKABLE);
  94
  95         spin_lock_irq(&current->sighand->siglock);
  96         saveset = current->blocked;
  97         current->blocked = newset;
  98         recalc_sigpending();
  99         spin_unlock_irq(&current->sighand->siglock);
 100
 101         regs->d0 = -EINTR;
 102         while (1) {
 103                 current->state = TASK_INTERRUPTIBLE;
 104                 schedule();
 105                 if (do_signal(&saveset, regs))
 106                         return -EINTR;
 107         }
 108 }
 109
 110 asmlinkage int
 111 sys_sigaction(int sig, const struct old_sigaction *act,
 112               struct old_sigaction *oact)
 113 {
 114         struct k_sigaction new_ka, old_ka;
 115         int ret;
 116
 117         if (act) {
 118                 old_sigset_t mask;
 119                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
 120                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
 121                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
 122                         return -EFAULT;
 123                 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
 124                 __get_user(mask, &act->sa_mask);
 125                 siginitset(&new_ka.sa.sa_mask, mask);
 126         }
 127
 128         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 129
 130         if (!ret && oact) {
 131                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
 132                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
 133                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
 134                         return -EFAULT;
 135                 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
 136                 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
 137         }
 138
 139         return ret;
 140 }
 141
 142 asmlinkage int
 143 sys_sigaltstack(const stack_t *uss, stack_t *uoss)
 144 {
 145         return do_sigaltstack(uss, uoss, rdusp());
 146 }
 147
 148
 149 /*
 150  * Do a signal return; undo the signal stack.
 151  *
 152  * Keep the return code on the stack quadword aligned!
 153  * That makes the cache flush below easier.
 154  */
 155
 156 struct sigframe
 157 {
 158         char *pretcode;
 159         int sig;
 160         int code;
 161         struct sigcontext *psc;
 162         char retcode[8];
 163         unsigned long extramask[_NSIG_WORDS-1];
 164         struct sigcontext sc;
 165 };
 166
 167 struct rt_sigframe
 168 {
 169         char *pretcode;
 170         int sig;
 171         struct siginfo *pinfo;
 172         void *puc;
 173         char retcode[8];
 174         struct siginfo info;
 175         struct ucontext uc;
 176 };
 177
 178 #ifdef CONFIG_FPU
 179
 180 static unsigned char fpu_version = 0;   /* version number of fpu, set by setup_frame */
 181
 182 static inline int restore_fpu_state(struct sigcontext *sc)
 183 {
 184         int err = 1;
 185
 186         if (FPU_IS_EMU) {
 187             /* restore registers */
 188             memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
 189             memcpy(current->thread.fp, sc->sc_fpregs, 24);
 190             return 0;
 191         }
 192
 193         if (sc->sc_fpstate[0]) {
 194             /* Verify the frame format.  */
 195             if (sc->sc_fpstate[0] != fpu_version)
 196                 goto out;
 197
 198             __asm__ volatile (".chip 68k/68881\n\t"
 199                               "fmovemx %0,%/fp0-%/fp1\n\t"
 200                               "fmoveml %1,%/fpcr/%/fpsr/%/fpiar\n\t"
 201                               ".chip 68k"
 202                               : /* no outputs */
 203                               : "m" (*sc->sc_fpregs), "m" (*sc->sc_fpcntl));
 204         }
 205         __asm__ volatile (".chip 68k/68881\n\t"
 206                           "frestore %0\n\t"
 207                           ".chip 68k" : : "m" (*sc->sc_fpstate));
 208         err = 0;
 209
 210 out:
 211         return err;
 212 }
 213
 214 #define FPCONTEXT_SIZE  216
 215 #define uc_fpstate      uc_filler[0]
 216 #define uc_formatvec    uc_filler[FPCONTEXT_SIZE/4]
 217 #define uc_extra        uc_filler[FPCONTEXT_SIZE/4+1]
 218
 219 static inline int rt_restore_fpu_state(struct ucontext *uc)
 220 {
 221         unsigned char fpstate[FPCONTEXT_SIZE];
 222         int context_size = 0;
 223         fpregset_t fpregs;
 224         int err = 1;
 225
 226         if (FPU_IS_EMU) {
 227                 /* restore fpu control register */
 228                 if (__copy_from_user(current->thread.fpcntl,
 229                                 &uc->uc_mcontext.fpregs.f_pcr, 12))
 230                         goto out;
 231                 /* restore all other fpu register */
 232                 if (__copy_from_user(current->thread.fp,
 233                                 uc->uc_mcontext.fpregs.f_fpregs, 96))
 234                         goto out;
 235                 return 0;
 236         }
 237
 238         if (__get_user(*(long *)fpstate, (long *)&uc->uc_fpstate))
 239                 goto out;
 240         if (fpstate[0]) {
 241                 context_size = fpstate[1];
 242
 243                 /* Verify the frame format.  */
 244                 if (fpstate[0] != fpu_version)
 245                         goto out;
 246                 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
 247                      sizeof(fpregs)))
 248                         goto out;
 249                 __asm__ volatile (".chip 68k/68881\n\t"
 250                                   "fmovemx %0,%/fp0-%/fp7\n\t"
 251                                   "fmoveml %1,%/fpcr/%/fpsr/%/fpiar\n\t"
 252                                   ".chip 68k"
 253                                   : /* no outputs */
 254                                   : "m" (*fpregs.f_fpregs),
 255                                     "m" (fpregs.f_pcr));
 256         }
 257         if (context_size &&
 258             __copy_from_user(fpstate + 4, (long *)&uc->uc_fpstate + 1,
 259                              context_size))
 260                 goto out;
 261         __asm__ volatile (".chip 68k/68881\n\t"
 262                           "frestore %0\n\t"
 263                           ".chip 68k" : : "m" (*fpstate));
 264         err = 0;
 265
 266 out:
 267         return err;
 268 }
 269
 270 #endif
 271
 272 static inline int
 273 restore_sigcontext(struct pt_regs *regs, struct sigcontext *usc, void *fp,
 274                    int *pd0)
 275 {
 276         int formatvec;
 277         struct sigcontext context;
 278         int err = 0;
 279
 280         /* get previous context */
 281         if (copy_from_user(&context, usc, sizeof(context)))
 282                 goto badframe;
 283
 284         /* restore passed registers */
 285         regs->d1 = context.sc_d1;
 286         regs->a0 = context.sc_a0;
 287         regs->a1 = context.sc_a1;
 288         regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
 289         regs->pc = context.sc_pc;
 290         regs->orig_d0 = -1;             /* disable syscall checks */
 291         wrusp(context.sc_usp);
 292         formatvec = context.sc_formatvec;
 293         regs->format = formatvec >> 12;
 294         regs->vector = formatvec & 0xfff;
 295
 296 #ifdef CONFIG_FPU
 297         err = restore_fpu_state(&context);
 298 #endif
 299
 300         *pd0 = context.sc_d0;
 301         return err;
 302
 303 badframe:
 304         return 1;
 305 }
 306
 307 static inline int
 308 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
 309                     struct ucontext *uc, int *pd0)
 310 {
 311         int temp;
 312         greg_t *gregs = uc->uc_mcontext.gregs;
 313         unsigned long usp;
 314         int err;
 315
 316         err = __get_user(temp, &uc->uc_mcontext.version);
 317         if (temp != MCONTEXT_VERSION)
 318                 goto badframe;
 319         /* restore passed registers */
 320         err |= __get_user(regs->d0, &gregs[0]);
 321         err |= __get_user(regs->d1, &gregs[1]);
 322         err |= __get_user(regs->d2, &gregs[2]);
 323         err |= __get_user(regs->d3, &gregs[3]);
 324         err |= __get_user(regs->d4, &gregs[4]);
 325         err |= __get_user(regs->d5, &gregs[5]);
 326         err |= __get_user(sw->d6, &gregs[6]);
 327         err |= __get_user(sw->d7, &gregs[7]);
 328         err |= __get_user(regs->a0, &gregs[8]);
 329         err |= __get_user(regs->a1, &gregs[9]);
 330         err |= __get_user(regs->a2, &gregs[10]);
 331         err |= __get_user(sw->a3, &gregs[11]);
 332         err |= __get_user(sw->a4, &gregs[12]);
 333         err |= __get_user(sw->a5, &gregs[13]);
 334         err |= __get_user(sw->a6, &gregs[14]);
 335         err |= __get_user(usp, &gregs[15]);
 336         wrusp(usp);
 337         err |= __get_user(regs->pc, &gregs[16]);
 338         err |= __get_user(temp, &gregs[17]);
 339         regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
 340         regs->orig_d0 = -1;             /* disable syscall checks */
 341         regs->format = temp >> 12;
 342         regs->vector = temp & 0xfff;
 343
 344         if (do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT)
 345                 goto badframe;
 346
 347         *pd0 = regs->d0;
 348         return err;
 349
 350 badframe:
 351         return 1;
 352 }
 353
 354 asmlinkage int do_sigreturn(unsigned long __unused)
 355 {
 356         struct switch_stack *sw = (struct switch_stack *) &__unused;
 357         struct pt_regs *regs = (struct pt_regs *) (sw + 1);
 358         unsigned long usp = rdusp();
 359         struct sigframe *frame = (struct sigframe *)(usp - 4);
 360         sigset_t set;
 361         int d0;
 362
 363         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 364                 goto badframe;
 365         if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
 366             (_NSIG_WORDS > 1 &&
 367              __copy_from_user(&set.sig[1], &frame->extramask,
 368                               sizeof(frame->extramask))))
 369                 goto badframe;
 370
 371         sigdelsetmask(&set, ~_BLOCKABLE);
 372         spin_lock_irq(&current->sighand->siglock);
 373         current->blocked = set;
 374         recalc_sigpending();
 375         spin_unlock_irq(&current->sighand->siglock);
 376
 377         if (restore_sigcontext(regs, &frame->sc, frame + 1, &d0))
 378                 goto badframe;
 379         return d0;
 380
 381 badframe:
 382         force_sig(SIGSEGV, current);
 383         return 0;
 384 }
 385
 386 asmlinkage int do_rt_sigreturn(unsigned long __unused)
 387 {
 388         struct switch_stack *sw = (struct switch_stack *) &__unused;
 389         struct pt_regs *regs = (struct pt_regs *) (sw + 1);
 390         unsigned long usp = rdusp();
 391         struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);
 392         sigset_t set;
 393         int d0;
 394
 395         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 396                 goto badframe;
 397         if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 398                 goto badframe;
 399
 400         sigdelsetmask(&set, ~_BLOCKABLE);
 401         spin_lock_irq(&current->sighand->siglock);
 402         current->blocked = set;
 403         recalc_sigpending();
 404         spin_unlock_irq(&current->sighand->siglock);
 405
 406         if (rt_restore_ucontext(regs, sw, &frame->uc, &d0))
 407                 goto badframe;
 408         return d0;
 409
 410 badframe:
 411         force_sig(SIGSEGV, current);
 412         return 0;
 413 }
 414
 415 #ifdef CONFIG_FPU
 416 /*
 417  * Set up a signal frame.
 418  */
 419
 420 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
 421 {
 422         if (FPU_IS_EMU) {
 423                 /* save registers */
 424                 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
 425                 memcpy(sc->sc_fpregs, current->thread.fp, 24);
 426                 return;
 427         }
 428
 429         __asm__ volatile (".chip 68k/68881\n\t"
 430                           "fsave %0\n\t"
 431                           ".chip 68k"
 432                           : : "m" (*sc->sc_fpstate) : "memory");
 433
 434         if (sc->sc_fpstate[0]) {
 435                 fpu_version = sc->sc_fpstate[0];
 436                 __asm__ volatile (".chip 68k/68881\n\t"
 437                                   "fmovemx %/fp0-%/fp1,%0\n\t"
 438                                   "fmoveml %/fpcr/%/fpsr/%/fpiar,%1\n\t"
 439                                   ".chip 68k"
 440                                   : /* no outputs */
 441                                   : "m" (*sc->sc_fpregs),
 442                                     "m" (*sc->sc_fpcntl)
 443                                   : "memory");
 444         }
 445 }
 446
 447 static inline int rt_save_fpu_state(struct ucontext *uc, struct pt_regs *regs)
 448 {
 449         unsigned char fpstate[FPCONTEXT_SIZE];
 450         int context_size = 0;
 451         int err = 0;
 452
 453         if (FPU_IS_EMU) {
 454                 /* save fpu control register */
 455                 err |= copy_to_user(&uc->uc_mcontext.fpregs.f_pcr,
 456                                 current->thread.fpcntl, 12);
 457                 /* save all other fpu register */
 458                 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
 459                                 current->thread.fp, 96);
 460                 return err;
 461         }
 462
 463         __asm__ volatile (".chip 68k/68881\n\t"
 464                           "fsave %0\n\t"
 465                           ".chip 68k"
 466                           : : "m" (*fpstate) : "memory");
 467
 468         err |= __put_user(*(long *)fpstate, (long *)&uc->uc_fpstate);
 469         if (fpstate[0]) {
 470                 fpregset_t fpregs;
 471                 context_size = fpstate[1];
 472                 fpu_version = fpstate[0];
 473                 __asm__ volatile (".chip 68k/68881\n\t"
 474                                   "fmovemx %/fp0-%/fp7,%0\n\t"
 475                                   "fmoveml %/fpcr/%/fpsr/%/fpiar,%1\n\t"
 476                                   ".chip 68k"
 477                                   : /* no outputs */
 478                                   : "m" (*fpregs.f_fpregs),
 479                                     "m" (fpregs.f_pcr)
 480                                   : "memory");
 481                 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
 482                                     sizeof(fpregs));
 483         }
 484         if (context_size)
 485                 err |= copy_to_user((long *)&uc->uc_fpstate + 1, fpstate + 4,
 486                                     context_size);
 487         return err;
 488 }
 489
 490 #endif
 491
 492 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
 493                              unsigned long mask)
 494 {
 495         sc->sc_mask = mask;
 496         sc->sc_usp = rdusp();
 497         sc->sc_d0 = regs->d0;
 498         sc->sc_d1 = regs->d1;
 499         sc->sc_a0 = regs->a0;
 500         sc->sc_a1 = regs->a1;
 501         sc->sc_sr = regs->sr;
 502         sc->sc_pc = regs->pc;
 503         sc->sc_formatvec = regs->format << 12 | regs->vector;
 504 #ifdef CONFIG_FPU
 505         save_fpu_state(sc, regs);
 506 #endif
 507 }
 508
 509 static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs)
 510 {
 511         struct switch_stack *sw = (struct switch_stack *)regs - 1;
 512         greg_t *gregs = uc->uc_mcontext.gregs;
 513         int err = 0;
 514
 515         err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
 516         err |= __put_user(regs->d0, &gregs[0]);
 517         err |= __put_user(regs->d1, &gregs[1]);
 518         err |= __put_user(regs->d2, &gregs[2]);
 519         err |= __put_user(regs->d3, &gregs[3]);
 520         err |= __put_user(regs->d4, &gregs[4]);
 521         err |= __put_user(regs->d5, &gregs[5]);
 522         err |= __put_user(sw->d6, &gregs[6]);
 523         err |= __put_user(sw->d7, &gregs[7]);
 524         err |= __put_user(regs->a0, &gregs[8]);
 525         err |= __put_user(regs->a1, &gregs[9]);
 526         err |= __put_user(regs->a2, &gregs[10]);
 527         err |= __put_user(sw->a3, &gregs[11]);
 528         err |= __put_user(sw->a4, &gregs[12]);
 529         err |= __put_user(sw->a5, &gregs[13]);
 530         err |= __put_user(sw->a6, &gregs[14]);
 531         err |= __put_user(rdusp(), &gregs[15]);
 532         err |= __put_user(regs->pc, &gregs[16]);
 533         err |= __put_user(regs->sr, &gregs[17]);
 534 #ifdef CONFIG_FPU
 535         err |= rt_save_fpu_state(uc, regs);
 536 #endif
 537         return err;
 538 }
 539
 540 static inline void push_cache (unsigned long vaddr)
 541 {
 542 }
 543
 544 static inline void *
 545 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
 546 {
 547         unsigned long usp;
 548
 549         /* Default to using normal stack.  */
 550         usp = rdusp();
 551
 552         /* This is the X/Open sanctioned signal stack switching.  */
 553         if (ka->sa.sa_flags & SA_ONSTACK) {
 554                 if (!on_sig_stack(usp))
 555                         usp = current->sas_ss_sp + current->sas_ss_size;
 556         }
 557         return (void *)((usp - frame_size) & -8UL);
 558 }
 559
 560 static void setup_frame (int sig, struct k_sigaction *ka,
 561                          sigset_t *set, struct pt_regs *regs)
 562 {
 563         struct sigframe *frame;
 564         struct sigcontext context;
 565         int err = 0;
 566
 567         frame = get_sigframe(ka, regs, sizeof(*frame));
 568
 569         err |= __put_user((current_thread_info()->exec_domain
 570                            && current_thread_info()->exec_domain->signal_invmap
 571                            && sig < 32
 572                            ? current_thread_info()->exec_domain->signal_invmap[sig]
 573                            : sig),
 574                           &frame->sig);
 575
 576         err |= __put_user(regs->vector, &frame->code);
 577         err |= __put_user(&frame->sc, &frame->psc);
 578
 579         if (_NSIG_WORDS > 1)
 580                 err |= copy_to_user(frame->extramask, &set->sig[1],
 581                                     sizeof(frame->extramask));
 582
 583         setup_sigcontext(&context, regs, set->sig[0]);
 584         err |= copy_to_user (&frame->sc, &context, sizeof(context));
 585
 586         /* Set up to return from userspace.  */
 587         err |= __put_user(frame->retcode, &frame->pretcode);
 588         /* moveq #,d0; trap #0 */
 589         err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
 590                           (long *)(frame->retcode));
 591
 592         if (err)
 593                 goto give_sigsegv;
 594
 595         push_cache ((unsigned long) &frame->retcode);
 596
 597         /* Set up registers for signal handler */
 598         wrusp ((unsigned long) frame);
 599         regs->pc = (unsigned long) ka->sa.sa_handler;
 600
 601 adjust_stack:
 602         /* Prepare to skip over the extra stuff in the exception frame.  */
 603         if (regs->stkadj) {
 604                 struct pt_regs *tregs =
 605                         (struct pt_regs *)((ulong)regs + regs->stkadj);
 606 #if DEBUG
 607                 printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
 608 #endif
 609                 /* This must be copied with decreasing addresses to
 610                    handle overlaps.  */
 611                 tregs->vector = 0;
 612                 tregs->format = 0;
 613                 tregs->pc = regs->pc;
 614                 tregs->sr = regs->sr;
 615         }
 616         return;
 617
 618 give_sigsegv:
 619         force_sigsegv(sig, current);
 620         goto adjust_stack;
 621 }
 622
 623 static void setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info,
 624                             sigset_t *set, struct pt_regs *regs)
 625 {
 626         struct rt_sigframe *frame;
 627         int err = 0;
 628
 629         frame = get_sigframe(ka, regs, sizeof(*frame));
 630
 631         err |= __put_user((current_thread_info()->exec_domain
 632                            && current_thread_info()->exec_domain->signal_invmap
 633                            && sig < 32
 634                            ? current_thread_info()->exec_domain->signal_invmap[sig]
 635                            : sig),
 636                           &frame->sig);
 637         err |= __put_user(&frame->info, &frame->pinfo);
 638         err |= __put_user(&frame->uc, &frame->puc);
 639         err |= copy_siginfo_to_user(&frame->info, info);
 640
 641         /* Create the ucontext.  */
 642         err |= __put_user(0, &frame->uc.uc_flags);
 643         err |= __put_user(0, &frame->uc.uc_link);
 644         err |= __put_user((void *)current->sas_ss_sp,
 645                           &frame->uc.uc_stack.ss_sp);
 646         err |= __put_user(sas_ss_flags(rdusp()),
 647                           &frame->uc.uc_stack.ss_flags);
 648         err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
 649         err |= rt_setup_ucontext(&frame->uc, regs);
 650         err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
 651
 652         /* Set up to return from userspace.  */
 653         err |= __put_user(frame->retcode, &frame->pretcode);
 654         /* moveq #,d0; notb d0; trap #0 */
 655         err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
 656                           (long *)(frame->retcode + 0));
 657         err |= __put_user(0x4e40, (short *)(frame->retcode + 4));
 658
 659         if (err)
 660                 goto give_sigsegv;
 661
 662         push_cache ((unsigned long) &frame->retcode);
 663
 664         /* Set up registers for signal handler */
 665         wrusp ((unsigned long) frame);
 666         regs->pc = (unsigned long) ka->sa.sa_handler;
 667
 668 adjust_stack:
 669         /* Prepare to skip over the extra stuff in the exception frame.  */
 670         if (regs->stkadj) {
 671                 struct pt_regs *tregs =
 672                         (struct pt_regs *)((ulong)regs + regs->stkadj);
 673 #if DEBUG
 674                 printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
 675 #endif
 676                 /* This must be copied with decreasing addresses to
 677                    handle overlaps.  */
 678                 tregs->vector = 0;
 679                 tregs->format = 0;
 680                 tregs->pc = regs->pc;
 681                 tregs->sr = regs->sr;
 682         }
 683         return;
 684
 685 give_sigsegv:
 686         force_sigsegv(sig, current);
 687         goto adjust_stack;
 688 }
 689
 690 static inline void
 691 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
 692 {
 693         switch (regs->d0) {
 694         case -ERESTARTNOHAND:
 695                 if (!has_handler)
 696                         goto do_restart;
 697                 regs->d0 = -EINTR;
 698                 break;
 699
 700         case -ERESTARTSYS:
 701                 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
 702                         regs->d0 = -EINTR;
 703                         break;
 704                 }
 705         /* fallthrough */
 706         case -ERESTARTNOINTR:
 707         do_restart:
 708                 regs->d0 = regs->orig_d0;
 709                 regs->pc -= 2;
 710                 break;
 711         }
 712 }
 713
 714 /*
 715  * OK, we're invoking a handler
 716  */
 717 static void
 718 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
 719               sigset_t *oldset, struct pt_regs *regs)
 720 {
 721         /* are we from a system call? */
 722         if (regs->orig_d0 >= 0)
 723                 /* If so, check system call restarting.. */
 724                 handle_restart(regs, ka, 1);
 725
 726         /* set up the stack frame */
 727         if (ka->sa.sa_flags & SA_SIGINFO)
 728                 setup_rt_frame(sig, ka, info, oldset, regs);
 729         else
 730                 setup_frame(sig, ka, oldset, regs);
 731
 732         if (ka->sa.sa_flags & SA_ONESHOT)
 733                 ka->sa.sa_handler = SIG_DFL;
 734
 735         spin_lock_irq(&current->sighand->siglock);
 736         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
 737         if (!(ka->sa.sa_flags & SA_NODEFER))
 738                 sigaddset(&current->blocked,sig);
 739         recalc_sigpending();
 740         spin_unlock_irq(&current->sighand->siglock);
 741 }
 742
 743 /*
 744  * Note that 'init' is a special process: it doesn't get signals it doesn't
 745  * want to handle. Thus you cannot kill init even with a SIGKILL even by
 746  * mistake.
 747  */
 748 asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
 749 {
 750         struct k_sigaction ka;
 751         siginfo_t info;
 752         int signr;
 753
 754         /*
 755          * We want the common case to go fast, which
 756          * is why we may in certain cases get here from
 757          * kernel mode. Just return without doing anything
 758          * if so.
 759          */
 760         if (!user_mode(regs))
 761                 return 1;
 762
 763         if (!oldset)
 764                 oldset = &current->blocked;
 765
 766         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 767         if (signr > 0) {
 768                 /* Whee!  Actually deliver the signal.  */
 769                 handle_signal(signr, &ka, &info, oldset, regs);
 770                 return 1;
 771         }
 772
 773         /* Did we come from a system call? */
 774         if (regs->orig_d0 >= 0) {
 775                 /* Restart the system call - no handlers present */
 776                 if (regs->d0 == -ERESTARTNOHAND
 777                     || regs->d0 == -ERESTARTSYS
 778                     || regs->d0 == -ERESTARTNOINTR) {
 779                         regs->d0 = regs->orig_d0;
 780                         regs->pc -= 2;
 781                 } else if (regs->d0 == -ERESTART_RESTARTBLOCK) {
 782                         regs->d0 = __NR_restart_syscall;
 783                         regs->pc -= 2;
 784                 }
 785         }
 786         return 0;
 787 }