arch/cris/arch-v32/kernel/signal.c

   1 /*
   2  * Copyright (C) 2003, Axis Communications AB.
   3  */
   4
   5 #include <linux/sched.h>
   6 #include <linux/mm.h>
   7 #include <linux/kernel.h>
   8 #include <linux/signal.h>
   9 #include <linux/errno.h>
  10 #include <linux/wait.h>
  11 #include <linux/ptrace.h>
  12 #include <linux/unistd.h>
  13 #include <linux/stddef.h>
  14 #include <linux/syscalls.h>
  15 #include <linux/vmalloc.h>
  16
  17 #include <asm/io.h>
  18 #include <asm/processor.h>
  19 #include <asm/ucontext.h>
  20 #include <asm/uaccess.h>
  21 #include <asm/arch/ptrace.h>
  22 #include <asm/arch/hwregs/cpu_vect.h>
  23
  24 extern unsigned long cris_signal_return_page;
  25
  26 /* Flag to check if a signal is blockable. */
  27 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  28
  29 /*
  30  * A syscall in CRIS is really a "break 13" instruction, which is 2
  31  * bytes. The registers is manipulated so upon return the instruction
  32  * will be executed again.
  33  *
  34  * This relies on that PC points to the instruction after the break call.
  35  */
  36 #define RESTART_CRIS_SYS(regs) regs->r10 = regs->orig_r10; regs->erp -= 2;
  37
  38 /* Signal frames. */
  39 struct signal_frame {
  40         struct sigcontext sc;
  41         unsigned long extramask[_NSIG_WORDS - 1];
  42         unsigned char retcode[8];       /* Trampoline code. */
  43 };
  44
  45 struct rt_signal_frame {
  46         struct siginfo *pinfo;
  47         void *puc;
  48         struct siginfo info;
  49         struct ucontext uc;
  50         unsigned char retcode[8];       /* Trampoline code. */
  51 };
  52
  53 int do_signal(int restart, sigset_t *oldset, struct pt_regs *regs);
  54 void keep_debug_flags(unsigned long oldccs, unsigned long oldspc,
  55                       struct pt_regs *regs);
  56 /*
  57  * Swap in the new signal mask, and wait for a signal. Define some
  58  * dummy arguments to be able to reach the regs argument.
  59  */
  60 int
  61 sys_sigsuspend(old_sigset_t mask, long r11, long r12, long r13, long mof,
  62                long srp, struct pt_regs *regs)
  63 {
  64         sigset_t saveset;
  65
  66         mask &= _BLOCKABLE;
  67
  68         spin_lock_irq(&current->sighand->siglock);
  69
  70         saveset = current->blocked;
  71
  72         siginitset(&current->blocked, mask);
  73
  74         recalc_sigpending();
  75         spin_unlock_irq(&current->sighand->siglock);
  76
  77         regs->r10 = -EINTR;
  78
  79         while (1) {
  80                 current->state = TASK_INTERRUPTIBLE;
  81                 schedule();
  82
  83                 if (do_signal(0, &saveset, regs)) {
  84                         /*
  85                          * This point is reached twice: once to call
  86                          * the signal handler, then again to return
  87                          * from the sigsuspend system call. When
  88                          * calling the signal handler, R10 hold the
  89                          * signal number as set by do_signal(). The
  90                          * sigsuspend  call will always return with
  91                          * the restored value above; -EINTR.
  92                          */
  93                         return regs->r10;
  94                 }
  95         }
  96 }
  97
  98 /* Define some dummy arguments to be able to reach the regs argument. */
  99 int
 100 sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, long r12, long r13,
 101                   long mof, long srp, struct pt_regs *regs)
 102 {
 103         sigset_t saveset;
 104         sigset_t newset;
 105
 106         if (sigsetsize != sizeof(sigset_t))
 107                 return -EINVAL;
 108
 109         if (copy_from_user(&newset, unewset, sizeof(newset)))
 110                 return -EFAULT;
 111
 112         sigdelsetmask(&newset, ~_BLOCKABLE);
 113         spin_lock_irq(&current->sighand->siglock);
 114
 115         saveset = current->blocked;
 116         current->blocked = newset;
 117
 118         recalc_sigpending();
 119         spin_unlock_irq(&current->sighand->siglock);
 120
 121         regs->r10 = -EINTR;
 122
 123         while (1) {
 124                 current->state = TASK_INTERRUPTIBLE;
 125                 schedule();
 126
 127                 if (do_signal(0, &saveset, regs)) {
 128                         /* See comment in function above. */
 129                         return regs->r10;
 130                 }
 131         }
 132 }
 133
 134 int
 135 sys_sigaction(int signal, const struct old_sigaction *act,
 136               struct old_sigaction *oact)
 137 {
 138         int retval;
 139         struct k_sigaction newk;
 140         struct k_sigaction oldk;
 141
 142         if (act) {
 143                 old_sigset_t mask;
 144
 145                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
 146                     __get_user(newk.sa.sa_handler, &act->sa_handler) ||
 147                     __get_user(newk.sa.sa_restorer, &act->sa_restorer))
 148                         return -EFAULT;
 149
 150                 __get_user(newk.sa.sa_flags, &act->sa_flags);
 151                 __get_user(mask, &act->sa_mask);
 152                 siginitset(&newk.sa.sa_mask, mask);
 153         }
 154
 155         retval = do_sigaction(signal, act ? &newk : NULL, oact ? &oldk : NULL);
 156
 157         if (!retval && oact) {
 158                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
 159                     __put_user(oldk.sa.sa_handler, &oact->sa_handler) ||
 160                     __put_user(oldk.sa.sa_restorer, &oact->sa_restorer))
 161                         return -EFAULT;
 162
 163                 __put_user(oldk.sa.sa_flags, &oact->sa_flags);
 164                 __put_user(oldk.sa.sa_mask.sig[0], &oact->sa_mask);
 165         }
 166
 167         return retval;
 168 }
 169
 170 int
 171 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
 172 {
 173         return do_sigaltstack(uss, uoss, rdusp());
 174 }
 175
 176 static int
 177 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 178 {
 179         unsigned int err = 0;
 180         unsigned long old_usp;
 181
 182         /* Always make any pending restarted system calls return -EINTR */
 183         current_thread_info()->restart_block.fn = do_no_restart_syscall;
 184
 185         /*
 186          * Restore the registers from &sc->regs. sc is already checked
 187          * for VERIFY_READ since the signal_frame was previously
 188          * checked in sys_sigreturn().
 189          */
 190         if (__copy_from_user(regs, sc, sizeof(struct pt_regs)))
 191                 goto badframe;
 192
 193         /* Make that the user-mode flag is set. */
 194         regs->ccs |= (1 << (U_CCS_BITNR + CCS_SHIFT));
 195
 196         /* Restore the old USP. */
 197         err |= __get_user(old_usp, &sc->usp);
 198         wrusp(old_usp);
 199
 200         return err;
 201
 202 badframe:
 203         return 1;
 204 }
 205
 206 /* Define some dummy arguments to be able to reach the regs argument. */
 207 asmlinkage int
 208 sys_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp,
 209               struct pt_regs *regs)
 210 {
 211         sigset_t set;
 212         struct signal_frame __user *frame;
 213         unsigned long oldspc = regs->spc;
 214         unsigned long oldccs = regs->ccs;
 215
 216         frame = (struct signal_frame *) rdusp();
 217
 218         /*
 219          * Since the signal is stacked on a dword boundary, the frame
 220          * should be dword aligned here as well. It it's not, then the
 221          * user is trying some funny business.
 222          */
 223         if (((long)frame) & 3)
 224                 goto badframe;
 225
 226         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 227                 goto badframe;
 228
 229         if (__get_user(set.sig[0], &frame->sc.oldmask) ||
 230             (_NSIG_WORDS > 1 && __copy_from_user(&set.sig[1],
 231                                                  frame->extramask,
 232                                                  sizeof(frame->extramask))))
 233                 goto badframe;
 234
 235         sigdelsetmask(&set, ~_BLOCKABLE);
 236         spin_lock_irq(&current->sighand->siglock);
 237
 238         current->blocked = set;
 239
 240         recalc_sigpending();
 241         spin_unlock_irq(&current->sighand->siglock);
 242
 243         if (restore_sigcontext(regs, &frame->sc))
 244                 goto badframe;
 245
 246         keep_debug_flags(oldccs, oldspc, regs);
 247
 248         return regs->r10;
 249
 250 badframe:
 251         force_sig(SIGSEGV, current);
 252         return 0;
 253 }
 254
 255 /* Define some dummy variables to be able to reach the regs argument. */
 256 asmlinkage int
 257 sys_rt_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp,
 258                  struct pt_regs *regs)
 259 {
 260         sigset_t set;
 261         struct rt_signal_frame __user *frame;
 262         unsigned long oldspc = regs->spc;
 263         unsigned long oldccs = regs->ccs;
 264
 265         frame = (struct rt_signal_frame *) rdusp();
 266
 267         /*
 268          * Since the signal is stacked on a dword boundary, the frame
 269          * should be dword aligned here as well. It it's not, then the
 270          * user is trying some funny business.
 271          */
 272         if (((long)frame) & 3)
 273                 goto badframe;
 274
 275         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 276                 goto badframe;
 277
 278         if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 279                 goto badframe;
 280
 281         sigdelsetmask(&set, ~_BLOCKABLE);
 282         spin_lock_irq(&current->sighand->siglock);
 283
 284         current->blocked = set;
 285
 286         recalc_sigpending();
 287         spin_unlock_irq(&current->sighand->siglock);
 288
 289         if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
 290                 goto badframe;
 291
 292         if (do_sigaltstack(&frame->uc.uc_stack, NULL, rdusp()) == -EFAULT)
 293                 goto badframe;
 294
 295         keep_debug_flags(oldccs, oldspc, regs);
 296
 297         return regs->r10;
 298
 299 badframe:
 300         force_sig(SIGSEGV, current);
 301         return 0;
 302 }
 303
 304 /* Setup a signal frame. */
 305 static int
 306 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
 307                  unsigned long mask)
 308 {
 309         int err;
 310         unsigned long usp;
 311
 312         err = 0;
 313         usp = rdusp();
 314
 315         /*
 316          * Copy the registers. They are located first in sc, so it's
 317          * possible to use sc directly.
 318          */
 319         err |= __copy_to_user(sc, regs, sizeof(struct pt_regs));
 320
 321         err |= __put_user(mask, &sc->oldmask);
 322         err |= __put_user(usp, &sc->usp);
 323
 324         return err;
 325 }
 326
 327 /* Figure out where to put the new signal frame - usually on the stack. */
 328 static inline void __user *
 329 get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
 330 {
 331         unsigned long sp;
 332
 333         sp = rdusp();
 334
 335         /* This is the X/Open sanctioned signal stack switching. */
 336         if (ka->sa.sa_flags & SA_ONSTACK) {
 337                 if (!on_sig_stack(sp))
 338                         sp = current->sas_ss_sp + current->sas_ss_size;
 339         }
 340
 341         /* Make sure the frame is dword-aligned. */
 342         sp &= ~3;
 343
 344         return (void __user *)(sp - frame_size);
 345 }
 346
 347 /* Grab and setup a signal frame.
 348  *
 349  * Basically a lot of state-info is stacked, and arranged for the
 350  * user-mode program to return to the kernel using either a trampiline
 351  * which performs the syscall sigreturn(), or a provided user-mode
 352  * trampoline.
 353   */
 354 static void
 355 setup_frame(int sig, struct k_sigaction *ka,  sigset_t *set,
 356             struct pt_regs * regs)
 357 {
 358         int err;
 359         unsigned long return_ip;
 360         struct signal_frame __user *frame;
 361
 362         err = 0;
 363         frame = get_sigframe(ka, regs, sizeof(*frame));
 364
 365         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 366                 goto give_sigsegv;
 367
 368         err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
 369
 370         if (err)
 371                 goto give_sigsegv;
 372
 373         if (_NSIG_WORDS > 1) {
 374                 err |= __copy_to_user(frame->extramask, &set->sig[1],
 375                                       sizeof(frame->extramask));
 376         }
 377
 378         if (err)
 379                 goto give_sigsegv;
 380
 381         /*
 382          * Set up to return from user-space. If provided, use a stub
 383          * already located in user-space.
 384          */
 385         if (ka->sa.sa_flags & SA_RESTORER) {
 386                 return_ip = (unsigned long)ka->sa.sa_restorer;
 387         } else {
 388                 /* Trampoline - the desired return ip is in the signal return page. */
 389                 return_ip = cris_signal_return_page;
 390
 391                 /*
 392                  * This is movu.w __NR_sigreturn, r9; break 13;
 393                  *
 394                  * WE DO NOT USE IT ANY MORE! It's only left here for historical
 395                  * reasons and because gdb uses it as a signature to notice
 396                  * signal handler stack frames.
 397                  */
 398                 err |= __put_user(0x9c5f,         (short __user*)(frame->retcode+0));
 399                 err |= __put_user(__NR_sigreturn, (short __user*)(frame->retcode+2));
 400                 err |= __put_user(0xe93d,         (short __user*)(frame->retcode+4));
 401         }
 402
 403         if (err)
 404                 goto give_sigsegv;
 405
 406         /*
 407          * Set up registers for signal handler.
 408          *
 409          * Where the code enters now.
 410          * Where the code enter later.
 411          * First argument, signo.
 412          */
 413         regs->erp = (unsigned long) ka->sa.sa_handler;
 414         regs->srp = return_ip;
 415         regs->r10 = sig;
 416
 417         /* Actually move the USP to reflect the stacked frame. */
 418         wrusp((unsigned long)frame);
 419
 420         return;
 421
 422 give_sigsegv:
 423         if (sig == SIGSEGV)
 424                 ka->sa.sa_handler = SIG_DFL;
 425
 426         force_sig(SIGSEGV, current);
 427 }
 428
 429 static void
 430 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 431                sigset_t *set, struct pt_regs * regs)
 432 {
 433         int err;
 434         unsigned long return_ip;
 435         struct rt_signal_frame __user *frame;
 436
 437         err = 0;
 438         frame = get_sigframe(ka, regs, sizeof(*frame));
 439
 440         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 441                 goto give_sigsegv;
 442
 443         /* TODO: what is the current->exec_domain stuff and invmap ? */
 444
 445         err |= __put_user(&frame->info, &frame->pinfo);
 446         err |= __put_user(&frame->uc, &frame->puc);
 447         err |= copy_siginfo_to_user(&frame->info, info);
 448
 449         if (err)
 450                 goto give_sigsegv;
 451
 452         /* Clear all the bits of the ucontext we don't use.  */
 453         err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
 454         err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
 455         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 456
 457         if (err)
 458                 goto give_sigsegv;
 459
 460         /*
 461          * Set up to return from user-space. If provided, use a stub
 462          * already located in user-space.
 463          */
 464         if (ka->sa.sa_flags & SA_RESTORER) {
 465                 return_ip = (unsigned long) ka->sa.sa_restorer;
 466         } else {
 467                 /* Trampoline - the desired return ip is in the signal return page. */
 468                 return_ip = cris_signal_return_page + 6;
 469
 470                 /*
 471                  * This is movu.w __NR_rt_sigreturn, r9; break 13;
 472                  *
 473                  * WE DO NOT USE IT ANY MORE! It's only left here for historical
 474                  * reasons and because gdb uses it as a signature to notice
 475                  * signal handler stack frames.
 476                  */
 477                 err |= __put_user(0x9c5f, (short __user*)(frame->retcode+0));
 478
 479                 err |= __put_user(__NR_rt_sigreturn,
 480                                   (short __user*)(frame->retcode+2));
 481
 482                 err |= __put_user(0xe93d, (short __user*)(frame->retcode+4));
 483         }
 484
 485         if (err)
 486                 goto give_sigsegv;
 487
 488         /*
 489          * Set up registers for signal handler.
 490          *
 491          * Where the code enters now.
 492          * Where the code enters later.
 493          * First argument is signo.
 494          * Second argument is (siginfo_t *).
 495          * Third argument is unused.
 496          */
 497         regs->erp = (unsigned long) ka->sa.sa_handler;
 498         regs->srp = return_ip;
 499         regs->r10 = sig;
 500         regs->r11 = (unsigned long) &frame->info;
 501         regs->r12 = 0;
 502
 503         /* Actually move the usp to reflect the stacked frame. */
 504         wrusp((unsigned long)frame);
 505
 506         return;
 507
 508 give_sigsegv:
 509         if (sig == SIGSEGV)
 510                 ka->sa.sa_handler = SIG_DFL;
 511
 512         force_sig(SIGSEGV, current);
 513 }
 514
 515 /* Invoke a singal handler to, well, handle the signal. */
 516 static inline void
 517 handle_signal(int canrestart, unsigned long sig,
 518               siginfo_t *info, struct k_sigaction *ka,
 519               sigset_t *oldset, struct pt_regs * regs)
 520 {
 521         /* Check if this got called from a system call. */
 522         if (canrestart) {
 523                 /* If so, check system call restarting. */
 524                 switch (regs->r10) {
 525                         case -ERESTART_RESTARTBLOCK:
 526                         case -ERESTARTNOHAND:
 527                                 /*
 528                                  * This means that the syscall should
 529                                  * only be restarted if there was no
 530                                  * handler for the signal, and since
 531                                  * this point isn't reached unless
 532                                  * there is a handler, there's no need
 533                                  * to restart.
 534                                  */
 535                                 regs->r10 = -EINTR;
 536                                 break;
 537
 538                         case -ERESTARTSYS:
 539                                 /*
 540                                  * This means restart the syscall if
 541                                  * there is no handler, or the handler
 542                                  * was registered with SA_RESTART.
 543                                  */
 544                                 if (!(ka->sa.sa_flags & SA_RESTART)) {
 545                                         regs->r10 = -EINTR;
 546                                         break;
 547                                 }
 548
 549                                 /* Fall through. */
 550
 551                         case -ERESTARTNOINTR:
 552                                 /*
 553                                  * This means that the syscall should
 554                                  * be called again after the signal
 555                                  * handler returns.
 556                                  */
 557                                 RESTART_CRIS_SYS(regs);
 558                                 break;
 559                 }
 560         }
 561
 562         /* Set up the stack frame. */
 563         if (ka->sa.sa_flags & SA_SIGINFO)
 564                 setup_rt_frame(sig, ka, info, oldset, regs);
 565         else
 566                 setup_frame(sig, ka, oldset, regs);
 567
 568         if (ka->sa.sa_flags & SA_ONESHOT)
 569                 ka->sa.sa_handler = SIG_DFL;
 570
 571         spin_lock_irq(&current->sighand->siglock);
 572         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
 573         if (!(ka->sa.sa_flags & SA_NODEFER))
 574                 sigaddset(&current->blocked,sig);
 575         recalc_sigpending();
 576         spin_unlock_irq(&current->sighand->siglock);
 577 }
 578
 579 /*
 580  * Note that 'init' is a special process: it doesn't get signals it doesn't
 581  * want to handle. Thus you cannot kill init even with a SIGKILL even by
 582  * mistake.
 583  *
 584  * Also note that the regs structure given here as an argument, is the latest
 585  * pushed pt_regs. It may or may not be the same as the first pushed registers
 586  * when the initial usermode->kernelmode transition took place. Therefore
 587  * we can use user_mode(regs) to see if we came directly from kernel or user
 588  * mode below.
 589  */
 590 int
 591 do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs)
 592 {
 593         int signr;
 594         siginfo_t info;
 595         struct k_sigaction ka;
 596
 597         /*
 598          * The common case should go fast, which is why this point is
 599          * reached from kernel-mode. If that's the case, just return
 600          * without doing anything.
 601          */
 602         if (!user_mode(regs))
 603                 return 1;
 604
 605         if (!oldset)
 606                 oldset = &current->blocked;
 607
 608         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 609
 610         if (signr > 0) {
 611                 /* Deliver the signal. */
 612                 handle_signal(canrestart, signr, &info, &ka, oldset, regs);
 613                 return 1;
 614         }
 615
 616         /* Got here from a system call? */
 617         if (canrestart) {
 618                 /* Restart the system call - no handlers present. */
 619                 if (regs->r10 == -ERESTARTNOHAND ||
 620                     regs->r10 == -ERESTARTSYS ||
 621                     regs->r10 == -ERESTARTNOINTR) {
 622                         RESTART_CRIS_SYS(regs);
 623                 }
 624
 625                 if (regs->r10 == -ERESTART_RESTARTBLOCK){
 626                         regs->r10 = __NR_restart_syscall;
 627                         regs->erp -= 2;
 628                 }
 629         }
 630
 631         return 0;
 632 }
 633
 634 asmlinkage void
 635 ugdb_trap_user(struct thread_info *ti, int sig)
 636 {
 637         if (((user_regs(ti)->exs & 0xff00) >> 8) != SINGLE_STEP_INTR_VECT) {
 638                 /* Zero single-step PC if the reason we stopped wasn't a single
 639                    step exception. This is to avoid relying on it when it isn't
 640                    reliable. */
 641                 user_regs(ti)->spc = 0;
 642         }
 643         /* FIXME: Filter out false h/w breakpoint hits (i.e. EDA
 644            not withing any configured h/w breakpoint range). Synchronize with
 645            what already exists for kernel debugging.  */
 646         if (((user_regs(ti)->exs & 0xff00) >> 8) == BREAK_8_INTR_VECT) {
 647                 /* Break 8: subtract 2 from ERP unless in a delay slot. */
 648                 if (!(user_regs(ti)->erp & 0x1))
 649                         user_regs(ti)->erp -= 2;
 650         }
 651         sys_kill(ti->task->pid, sig);
 652 }
 653
 654 void
 655 keep_debug_flags(unsigned long oldccs, unsigned long oldspc,
 656                  struct pt_regs *regs)
 657 {
 658         if (oldccs & (1 << Q_CCS_BITNR)) {
 659                 /* Pending single step due to single-stepping the break 13
 660                    in the signal trampoline: keep the Q flag. */
 661                 regs->ccs |= (1 << Q_CCS_BITNR);
 662                 /* S flag should be set - complain if it's not. */
 663                 if (!(oldccs & (1 << (S_CCS_BITNR + CCS_SHIFT)))) {
 664                         printk("Q flag but no S flag?");
 665                 }
 666                 regs->ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT));
 667                 /* Assume the SPC is valid and interesting. */
 668                 regs->spc = oldspc;
 669
 670         } else if (oldccs & (1 << (S_CCS_BITNR + CCS_SHIFT))) {
 671                 /* If a h/w bp was set in the signal handler we need
 672                    to keep the S flag. */
 673                 regs->ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT));
 674                 /* Don't keep the old SPC though; if we got here due to
 675                    a single-step, the Q flag should have been set. */
 676         } else if (regs->spc) {
 677                 /* If we were single-stepping *before* the signal was taken,
 678                    we don't want to restore that state now, because GDB will
 679                    have forgotten all about it. */
 680                 regs->spc = 0;
 681                 regs->ccs &= ~(1 << (S_CCS_BITNR + CCS_SHIFT));
 682         }
 683 }
 684
 685 /* Set up the trampolines on the signal return page. */
 686 int __init
 687 cris_init_signal(void)
 688 {
 689         u16* data = (u16*)kmalloc(PAGE_SIZE, GFP_KERNEL);
 690
 691         /* This is movu.w __NR_sigreturn, r9; break 13; */
 692         data[0] = 0x9c5f;
 693         data[1] = __NR_sigreturn;
 694         data[2] = 0xe93d;
 695         /* This is movu.w __NR_rt_sigreturn, r9; break 13; */
 696         data[3] = 0x9c5f;
 697         data[4] = __NR_rt_sigreturn;
 698         data[5] = 0xe93d;
 699
 700         /* Map to userspace with appropriate permissions (no write access...) */
 701         cris_signal_return_page = (unsigned long)
 702           __ioremap_prot(virt_to_phys(data), PAGE_SIZE, PAGE_SIGNAL_TRAMPOLINE);
 703
 704         return 0;
 705 }
 706
 707 __initcall(cris_init_signal);