arch/mips/kernel/signal.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1991, 1992  Linus Torvalds
   7  * Copyright (C) 1994 - 2000  Ralf Baechle
   8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   9  * Copyright (C) 2014, Imagination Technologies Ltd.
  10  */
  11 #include <linux/cache.h>
  12 #include <linux/context_tracking.h>
  13 #include <linux/irqflags.h>
  14 #include <linux/sched.h>
  15 #include <linux/mm.h>
  16 #include <linux/personality.h>
  17 #include <linux/smp.h>
  18 #include <linux/kernel.h>
  19 #include <linux/signal.h>
  20 #include <linux/errno.h>
  21 #include <linux/wait.h>
  22 #include <linux/ptrace.h>
  23 #include <linux/unistd.h>
  24 #include <linux/compiler.h>
  25 #include <linux/syscalls.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/tracehook.h>
  28
  29 #include <asm/abi.h>
  30 #include <asm/asm.h>
  31 #include <linux/bitops.h>
  32 #include <asm/cacheflush.h>
  33 #include <asm/fpu.h>
  34 #include <asm/sim.h>
  35 #include <asm/ucontext.h>
  36 #include <asm/cpu-features.h>
  37 #include <asm/war.h>
  38 #include <asm/vdso.h>
  39 #include <asm/dsp.h>
  40 #include <asm/inst.h>
  41
  42 #include "signal-common.h"
  43
  44 static int (*save_fp_context)(struct sigcontext __user *sc);
  45 static int (*restore_fp_context)(struct sigcontext __user *sc);
  46
  47 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
  48 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
  49
  50 struct sigframe {
  51         u32 sf_ass[4];          /* argument save space for o32 */
  52         u32 sf_pad[2];          /* Was: signal trampoline */
  53         struct sigcontext sf_sc;
  54         sigset_t sf_mask;
  55 };
  56
  57 struct rt_sigframe {
  58         u32 rs_ass[4];          /* argument save space for o32 */
  59         u32 rs_pad[2];          /* Was: signal trampoline */
  60         struct siginfo rs_info;
  61         struct ucontext rs_uc;
  62 };
  63
  64 /*
  65  * Thread saved context copy to/from a signal context presumed to be on the
  66  * user stack, and therefore accessed with appropriate macros from uaccess.h.
  67  */
  68 static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
  69 {
  70         int i;
  71         int err = 0;
  72
  73         for (i = 0; i < NUM_FPU_REGS; i++) {
  74                 err |=
  75                     __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
  76                                &sc->sc_fpregs[i]);
  77         }
  78         err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
  79
  80         return err;
  81 }
  82
  83 static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
  84 {
  85         int i;
  86         int err = 0;
  87         u64 fpr_val;
  88
  89         for (i = 0; i < NUM_FPU_REGS; i++) {
  90                 err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
  91                 set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
  92         }
  93         err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
  94
  95         return err;
  96 }
  97
  98 /*
  99  * Helper routines
 100  */
 101 static int protected_save_fp_context(struct sigcontext __user *sc)
 102 {
 103         int err;
 104 #ifndef CONFIG_EVA
 105         while (1) {
 106                 lock_fpu_owner();
 107                 if (is_fpu_owner()) {
 108                         err = save_fp_context(sc);
 109                         unlock_fpu_owner();
 110                 } else {
 111                         unlock_fpu_owner();
 112                         err = copy_fp_to_sigcontext(sc);
 113                 }
 114                 if (likely(!err))
 115                         break;
 116                 /* touch the sigcontext and try again */
 117                 err = __put_user(0, &sc->sc_fpregs[0]) |
 118                         __put_user(0, &sc->sc_fpregs[31]) |
 119                         __put_user(0, &sc->sc_fpc_csr);
 120                 if (err)
 121                         break;  /* really bad sigcontext */
 122         }
 123 #else
 124         /*
 125          * EVA does not have FPU EVA instructions so saving fpu context directly
 126          * does not work.
 127          */
 128         lose_fpu(1);
 129         err = save_fp_context(sc); /* this might fail */
 130 #endif
 131         return err;
 132 }
 133
 134 static int protected_restore_fp_context(struct sigcontext __user *sc)
 135 {
 136         int err, tmp __maybe_unused;
 137 #ifndef CONFIG_EVA
 138         while (1) {
 139                 lock_fpu_owner();
 140                 if (is_fpu_owner()) {
 141                         err = restore_fp_context(sc);
 142                         unlock_fpu_owner();
 143                 } else {
 144                         unlock_fpu_owner();
 145                         err = copy_fp_from_sigcontext(sc);
 146                 }
 147                 if (likely(!err))
 148                         break;
 149                 /* touch the sigcontext and try again */
 150                 err = __get_user(tmp, &sc->sc_fpregs[0]) |
 151                         __get_user(tmp, &sc->sc_fpregs[31]) |
 152                         __get_user(tmp, &sc->sc_fpc_csr);
 153                 if (err)
 154                         break;  /* really bad sigcontext */
 155         }
 156 #else
 157         /*
 158          * EVA does not have FPU EVA instructions so restoring fpu context
 159          * directly does not work.
 160          */
 161         lose_fpu(0);
 162         err = restore_fp_context(sc); /* this might fail */
 163 #endif
 164         return err;
 165 }
 166
 167 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 168 {
 169         int err = 0;
 170         int i;
 171         unsigned int used_math;
 172
 173         err |= __put_user(regs->cp0_epc, &sc->sc_pc);
 174
 175         err |= __put_user(0, &sc->sc_regs[0]);
 176         for (i = 1; i < 32; i++)
 177                 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
 178
 179 #ifdef CONFIG_CPU_HAS_SMARTMIPS
 180         err |= __put_user(regs->acx, &sc->sc_acx);
 181 #endif
 182         err |= __put_user(regs->hi, &sc->sc_mdhi);
 183         err |= __put_user(regs->lo, &sc->sc_mdlo);
 184         if (cpu_has_dsp) {
 185                 err |= __put_user(mfhi1(), &sc->sc_hi1);
 186                 err |= __put_user(mflo1(), &sc->sc_lo1);
 187                 err |= __put_user(mfhi2(), &sc->sc_hi2);
 188                 err |= __put_user(mflo2(), &sc->sc_lo2);
 189                 err |= __put_user(mfhi3(), &sc->sc_hi3);
 190                 err |= __put_user(mflo3(), &sc->sc_lo3);
 191                 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
 192         }
 193
 194         used_math = !!used_math();
 195         err |= __put_user(used_math, &sc->sc_used_math);
 196
 197         if (used_math) {
 198                 /*
 199                  * Save FPU state to signal context. Signal handler
 200                  * will "inherit" current FPU state.
 201                  */
 202                 err |= protected_save_fp_context(sc);
 203         }
 204         return err;
 205 }
 206
 207 int fpcsr_pending(unsigned int __user *fpcsr)
 208 {
 209         int err, sig = 0;
 210         unsigned int csr, enabled;
 211
 212         err = __get_user(csr, fpcsr);
 213         enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
 214         /*
 215          * If the signal handler set some FPU exceptions, clear it and
 216          * send SIGFPE.
 217          */
 218         if (csr & enabled) {
 219                 csr &= ~enabled;
 220                 err |= __put_user(csr, fpcsr);
 221                 sig = SIGFPE;
 222         }
 223         return err ?: sig;
 224 }
 225
 226 static int
 227 check_and_restore_fp_context(struct sigcontext __user *sc)
 228 {
 229         int err, sig;
 230
 231         err = sig = fpcsr_pending(&sc->sc_fpc_csr);
 232         if (err > 0)
 233                 err = 0;
 234         err |= protected_restore_fp_context(sc);
 235         return err ?: sig;
 236 }
 237
 238 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 239 {
 240         unsigned int used_math;
 241         unsigned long treg;
 242         int err = 0;
 243         int i;
 244
 245         /* Always make any pending restarted system calls return -EINTR */
 246         current_thread_info()->restart_block.fn = do_no_restart_syscall;
 247
 248         err |= __get_user(regs->cp0_epc, &sc->sc_pc);
 249
 250 #ifdef CONFIG_CPU_HAS_SMARTMIPS
 251         err |= __get_user(regs->acx, &sc->sc_acx);
 252 #endif
 253         err |= __get_user(regs->hi, &sc->sc_mdhi);
 254         err |= __get_user(regs->lo, &sc->sc_mdlo);
 255         if (cpu_has_dsp) {
 256                 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
 257                 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
 258                 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
 259                 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
 260                 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
 261                 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
 262                 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
 263         }
 264
 265         for (i = 1; i < 32; i++)
 266                 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
 267
 268         err |= __get_user(used_math, &sc->sc_used_math);
 269         conditional_used_math(used_math);
 270
 271         if (used_math) {
 272                 /* restore fpu context if we have used it before */
 273                 if (!err)
 274                         err = check_and_restore_fp_context(sc);
 275         } else {
 276                 /* signal handler may have used FPU.  Give it up. */
 277                 lose_fpu(0);
 278         }
 279
 280         return err;
 281 }
 282
 283 void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
 284                           size_t frame_size)
 285 {
 286         unsigned long sp;
 287
 288         /* Default to using normal stack */
 289         sp = regs->regs[29];
 290
 291         /*
 292          * FPU emulator may have it's own trampoline active just
 293          * above the user stack, 16-bytes before the next lowest
 294          * 16 byte boundary.  Try to avoid trashing it.
 295          */
 296         sp -= 32;
 297
 298         /* This is the X/Open sanctioned signal stack switching.  */
 299         if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
 300                 sp = current->sas_ss_sp + current->sas_ss_size;
 301
 302         return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
 303 }
 304
 305 /*
 306  * Atomically swap in the new signal mask, and wait for a signal.
 307  */
 308
 309 #ifdef CONFIG_TRAD_SIGNALS
 310 SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
 311 {
 312         return sys_rt_sigsuspend(uset, sizeof(sigset_t));
 313 }
 314 #endif
 315
 316 #ifdef CONFIG_TRAD_SIGNALS
 317 SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
 318         struct sigaction __user *, oact)
 319 {
 320         struct k_sigaction new_ka, old_ka;
 321         int ret;
 322         int err = 0;
 323
 324         if (act) {
 325                 old_sigset_t mask;
 326
 327                 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
 328                         return -EFAULT;
 329                 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
 330                 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
 331                 err |= __get_user(mask, &act->sa_mask.sig[0]);
 332                 if (err)
 333                         return -EFAULT;
 334
 335                 siginitset(&new_ka.sa.sa_mask, mask);
 336         }
 337
 338         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 339
 340         if (!ret && oact) {
 341                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
 342                         return -EFAULT;
 343                 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
 344                 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
 345                 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
 346                 err |= __put_user(0, &oact->sa_mask.sig[1]);
 347                 err |= __put_user(0, &oact->sa_mask.sig[2]);
 348                 err |= __put_user(0, &oact->sa_mask.sig[3]);
 349                 if (err)
 350                         return -EFAULT;
 351         }
 352
 353         return ret;
 354 }
 355 #endif
 356
 357 #ifdef CONFIG_TRAD_SIGNALS
 358 asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
 359 {
 360         struct sigframe __user *frame;
 361         sigset_t blocked;
 362         int sig;
 363
 364         frame = (struct sigframe __user *) regs.regs[29];
 365         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 366                 goto badframe;
 367         if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
 368                 goto badframe;
 369
 370         set_current_blocked(&blocked);
 371
 372         sig = restore_sigcontext(&regs, &frame->sf_sc);
 373         if (sig < 0)
 374                 goto badframe;
 375         else if (sig)
 376                 force_sig(sig, current);
 377
 378         /*
 379          * Don't let your children do this ...
 380          */
 381         __asm__ __volatile__(
 382                 "move\t$29, %0\n\t"
 383                 "j\tsyscall_exit"
 384                 :/* no outputs */
 385                 :"r" (&regs));
 386         /* Unreached */
 387
 388 badframe:
 389         force_sig(SIGSEGV, current);
 390 }
 391 #endif /* CONFIG_TRAD_SIGNALS */
 392
 393 asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
 394 {
 395         struct rt_sigframe __user *frame;
 396         sigset_t set;
 397         int sig;
 398
 399         frame = (struct rt_sigframe __user *) regs.regs[29];
 400         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 401                 goto badframe;
 402         if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
 403                 goto badframe;
 404
 405         set_current_blocked(&set);
 406
 407         sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
 408         if (sig < 0)
 409                 goto badframe;
 410         else if (sig)
 411                 force_sig(sig, current);
 412
 413         if (restore_altstack(&frame->rs_uc.uc_stack))
 414                 goto badframe;
 415
 416         /*
 417          * Don't let your children do this ...
 418          */
 419         __asm__ __volatile__(
 420                 "move\t$29, %0\n\t"
 421                 "j\tsyscall_exit"
 422                 :/* no outputs */
 423                 :"r" (&regs));
 424         /* Unreached */
 425
 426 badframe:
 427         force_sig(SIGSEGV, current);
 428 }
 429
 430 #ifdef CONFIG_TRAD_SIGNALS
 431 static int setup_frame(void *sig_return, struct k_sigaction *ka,
 432                        struct pt_regs *regs, int signr, sigset_t *set)
 433 {
 434         struct sigframe __user *frame;
 435         int err = 0;
 436
 437         frame = get_sigframe(ka, regs, sizeof(*frame));
 438         if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
 439                 goto give_sigsegv;
 440
 441         err |= setup_sigcontext(regs, &frame->sf_sc);
 442         err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
 443         if (err)
 444                 goto give_sigsegv;
 445
 446         /*
 447          * Arguments to signal handler:
 448          *
 449          *   a0 = signal number
 450          *   a1 = 0 (should be cause)
 451          *   a2 = pointer to struct sigcontext
 452          *
 453          * $25 and c0_epc point to the signal handler, $29 points to the
 454          * struct sigframe.
 455          */
 456         regs->regs[ 4] = signr;
 457         regs->regs[ 5] = 0;
 458         regs->regs[ 6] = (unsigned long) &frame->sf_sc;
 459         regs->regs[29] = (unsigned long) frame;
 460         regs->regs[31] = (unsigned long) sig_return;
 461         regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
 462
 463         DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
 464                current->comm, current->pid,
 465                frame, regs->cp0_epc, regs->regs[31]);
 466         return 0;
 467
 468 give_sigsegv:
 469         force_sigsegv(signr, current);
 470         return -EFAULT;
 471 }
 472 #endif
 473
 474 static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
 475                           struct pt_regs *regs, int signr, sigset_t *set,
 476                           siginfo_t *info)
 477 {
 478         struct rt_sigframe __user *frame;
 479         int err = 0;
 480
 481         frame = get_sigframe(ka, regs, sizeof(*frame));
 482         if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
 483                 goto give_sigsegv;
 484
 485         /* Create siginfo.  */
 486         err |= copy_siginfo_to_user(&frame->rs_info, info);
 487
 488         /* Create the ucontext.  */
 489         err |= __put_user(0, &frame->rs_uc.uc_flags);
 490         err |= __put_user(NULL, &frame->rs_uc.uc_link);
 491         err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
 492         err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
 493         err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
 494
 495         if (err)
 496                 goto give_sigsegv;
 497
 498         /*
 499          * Arguments to signal handler:
 500          *
 501          *   a0 = signal number
 502          *   a1 = 0 (should be cause)
 503          *   a2 = pointer to ucontext
 504          *
 505          * $25 and c0_epc point to the signal handler, $29 points to
 506          * the struct rt_sigframe.
 507          */
 508         regs->regs[ 4] = signr;
 509         regs->regs[ 5] = (unsigned long) &frame->rs_info;
 510         regs->regs[ 6] = (unsigned long) &frame->rs_uc;
 511         regs->regs[29] = (unsigned long) frame;
 512         regs->regs[31] = (unsigned long) sig_return;
 513         regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
 514
 515         DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
 516                current->comm, current->pid,
 517                frame, regs->cp0_epc, regs->regs[31]);
 518
 519         return 0;
 520
 521 give_sigsegv:
 522         force_sigsegv(signr, current);
 523         return -EFAULT;
 524 }
 525
 526 struct mips_abi mips_abi = {
 527 #ifdef CONFIG_TRAD_SIGNALS
 528         .setup_frame    = setup_frame,
 529         .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
 530 #endif
 531         .setup_rt_frame = setup_rt_frame,
 532         .rt_signal_return_offset =
 533                 offsetof(struct mips_vdso, rt_signal_trampoline),
 534         .restart        = __NR_restart_syscall
 535 };
 536
 537 static void handle_signal(unsigned long sig, siginfo_t *info,
 538         struct k_sigaction *ka, struct pt_regs *regs)
 539 {
 540         sigset_t *oldset = sigmask_to_save();
 541         int ret;
 542         struct mips_abi *abi = current->thread.abi;
 543 #ifdef CONFIG_CPU_MICROMIPS
 544         void *vdso;
 545         unsigned int tmp = (unsigned int)current->mm->context.vdso;
 546
 547         set_isa16_mode(tmp);
 548         vdso = (void *)tmp;
 549 #else
 550         void *vdso = current->mm->context.vdso;
 551 #endif
 552
 553         if (regs->regs[0]) {
 554                 switch(regs->regs[2]) {
 555                 case ERESTART_RESTARTBLOCK:
 556                 case ERESTARTNOHAND:
 557                         regs->regs[2] = EINTR;
 558                         break;
 559                 case ERESTARTSYS:
 560                         if (!(ka->sa.sa_flags & SA_RESTART)) {
 561                                 regs->regs[2] = EINTR;
 562                                 break;
 563                         }
 564                 /* fallthrough */
 565                 case ERESTARTNOINTR:
 566                         regs->regs[7] = regs->regs[26];
 567                         regs->regs[2] = regs->regs[0];
 568                         regs->cp0_epc -= 4;
 569                 }
 570
 571                 regs->regs[0] = 0;              /* Don't deal with this again.  */
 572         }
 573
 574         if (sig_uses_siginfo(ka))
 575                 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
 576                                           ka, regs, sig, oldset, info);
 577         else
 578                 ret = abi->setup_frame(vdso + abi->signal_return_offset,
 579                                        ka, regs, sig, oldset);
 580
 581         if (ret)
 582                 return;
 583
 584         signal_delivered(sig, info, ka, regs, 0);
 585 }
 586
 587 static void do_signal(struct pt_regs *regs)
 588 {
 589         struct k_sigaction ka;
 590         siginfo_t info;
 591         int signr;
 592
 593         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 594         if (signr > 0) {
 595                 /* Whee!  Actually deliver the signal.  */
 596                 handle_signal(signr, &info, &ka, regs);
 597                 return;
 598         }
 599
 600         if (regs->regs[0]) {
 601                 switch (regs->regs[2]) {
 602                 case ERESTARTNOHAND:
 603                 case ERESTARTSYS:
 604                 case ERESTARTNOINTR:
 605                         regs->regs[2] = regs->regs[0];
 606                         regs->regs[7] = regs->regs[26];
 607                         regs->cp0_epc -= 4;
 608                         break;
 609
 610                 case ERESTART_RESTARTBLOCK:
 611                         regs->regs[2] = current->thread.abi->restart;
 612                         regs->regs[7] = regs->regs[26];
 613                         regs->cp0_epc -= 4;
 614                         break;
 615                 }
 616                 regs->regs[0] = 0;      /* Don't deal with this again.  */
 617         }
 618
 619         /*
 620          * If there's no signal to deliver, we just put the saved sigmask
 621          * back
 622          */
 623         restore_saved_sigmask();
 624 }
 625
 626 /*
 627  * notification of userspace execution resumption
 628  * - triggered by the TIF_WORK_MASK flags
 629  */
 630 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
 631         __u32 thread_info_flags)
 632 {
 633         local_irq_enable();
 634
 635         user_exit();
 636
 637         /* deal with pending signal delivery */
 638         if (thread_info_flags & _TIF_SIGPENDING)
 639                 do_signal(regs);
 640
 641         if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 642                 clear_thread_flag(TIF_NOTIFY_RESUME);
 643                 tracehook_notify_resume(regs);
 644         }
 645
 646         user_enter();
 647 }
 648
 649 #ifdef CONFIG_SMP
 650 #ifndef CONFIG_EVA
 651 static int smp_save_fp_context(struct sigcontext __user *sc)
 652 {
 653         return raw_cpu_has_fpu
 654                ? _save_fp_context(sc)
 655                : copy_fp_to_sigcontext(sc);
 656 }
 657
 658 static int smp_restore_fp_context(struct sigcontext __user *sc)
 659 {
 660         return raw_cpu_has_fpu
 661                ? _restore_fp_context(sc)
 662                : copy_fp_from_sigcontext(sc);
 663 }
 664 #endif /* CONFIG_EVA */
 665 #endif
 666
 667 static int signal_setup(void)
 668 {
 669 #ifndef CONFIG_EVA
 670 #ifdef CONFIG_SMP
 671         /* For now just do the cpu_has_fpu check when the functions are invoked */
 672         save_fp_context = smp_save_fp_context;
 673         restore_fp_context = smp_restore_fp_context;
 674 #else
 675         if (cpu_has_fpu) {
 676                 save_fp_context = _save_fp_context;
 677                 restore_fp_context = _restore_fp_context;
 678         } else {
 679                 save_fp_context = copy_fp_from_sigcontext;
 680                 restore_fp_context = copy_fp_to_sigcontext;
 681         }
 682 #endif /* CONFIG_SMP */
 683 #else
 684         save_fp_context = copy_fp_from_sigcontext;;
 685         restore_fp_context = copy_fp_to_sigcontext;
 686 #endif
 687
 688         return 0;
 689 }
 690
 691 arch_initcall(signal_setup);