arch/sh/kernel/signal_64.c

   1 /*
   2  * arch/sh/kernel/signal_64.c
   3  *
   4  * Copyright (C) 2000, 2001  Paolo Alberelli
   5  * Copyright (C) 2003 - 2008  Paul Mundt
   6  * Copyright (C) 2004  Richard Curnow
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  */
  12 #include <linux/rwsem.h>
  13 #include <linux/sched.h>
  14 #include <linux/mm.h>
  15 #include <linux/smp.h>
  16 #include <linux/kernel.h>
  17 #include <linux/signal.h>
  18 #include <linux/errno.h>
  19 #include <linux/wait.h>
  20 #include <linux/personality.h>
  21 #include <linux/ptrace.h>
  22 #include <linux/unistd.h>
  23 #include <linux/stddef.h>
  24 #include <linux/tracehook.h>
  25 #include <asm/ucontext.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/pgtable.h>
  28 #include <asm/cacheflush.h>
  29 #include <asm/fpu.h>
  30
  31 #define REG_RET 9
  32 #define REG_ARG1 2
  33 #define REG_ARG2 3
  34 #define REG_ARG3 4
  35 #define REG_SP 15
  36 #define REG_PR 18
  37 #define REF_REG_RET regs->regs[REG_RET]
  38 #define REF_REG_SP regs->regs[REG_SP]
  39 #define DEREF_REG_PR regs->regs[REG_PR]
  40
  41 #define DEBUG_SIG 0
  42
  43 static void
  44 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
  45                 struct pt_regs * regs);
  46
  47 static inline void
  48 handle_syscall_restart(struct pt_regs *regs, struct sigaction *sa)
  49 {
  50         /* If we're not from a syscall, bail out */
  51         if (regs->syscall_nr < 0)
  52                 return;
  53
  54         /* check for system call restart.. */
  55         switch (regs->regs[REG_RET]) {
  56                 case -ERESTART_RESTARTBLOCK:
  57                 case -ERESTARTNOHAND:
  58                 no_system_call_restart:
  59                         regs->regs[REG_RET] = -EINTR;
  60                         break;
  61
  62                 case -ERESTARTSYS:
  63                         if (!(sa->sa_flags & SA_RESTART))
  64                                 goto no_system_call_restart;
  65                 /* fallthrough */
  66                 case -ERESTARTNOINTR:
  67                         /* Decode syscall # */
  68                         regs->regs[REG_RET] = regs->syscall_nr;
  69                         regs->pc -= 4;
  70                         break;
  71         }
  72 }
  73
  74 /*
  75  * Note that 'init' is a special process: it doesn't get signals it doesn't
  76  * want to handle. Thus you cannot kill init even with a SIGKILL even by
  77  * mistake.
  78  *
  79  * Note that we go through the signals twice: once to check the signals that
  80  * the kernel can handle, and then we build all the user-level signal handling
  81  * stack-frames in one go after that.
  82  */
  83 static void do_signal(struct pt_regs *regs)
  84 {
  85         siginfo_t info;
  86         int signr;
  87         struct k_sigaction ka;
  88
  89         /*
  90          * We want the common case to go fast, which
  91          * is why we may in certain cases get here from
  92          * kernel mode. Just return without doing anything
  93          * if so.
  94          */
  95         if (!user_mode(regs))
  96                 return;
  97
  98         signr = get_signal_to_deliver(&info, &ka, regs, 0);
  99         if (signr > 0) {
 100                 handle_syscall_restart(regs, &ka.sa);
 101
 102                 /* Whee!  Actually deliver the signal.  */
 103                 handle_signal(signr, &info, &ka, regs);
 104                 return;
 105         }
 106
 107         /* Did we come from a system call? */
 108         if (regs->syscall_nr >= 0) {
 109                 /* Restart the system call - no handlers present */
 110                 switch (regs->regs[REG_RET]) {
 111                 case -ERESTARTNOHAND:
 112                 case -ERESTARTSYS:
 113                 case -ERESTARTNOINTR:
 114                         /* Decode Syscall # */
 115                         regs->regs[REG_RET] = regs->syscall_nr;
 116                         regs->pc -= 4;
 117                         break;
 118
 119                 case -ERESTART_RESTARTBLOCK:
 120                         regs->regs[REG_RET] = __NR_restart_syscall;
 121                         regs->pc -= 4;
 122                         break;
 123                 }
 124         }
 125
 126         /* No signal to deliver -- put the saved sigmask back */
 127         restore_saved_sigmask();
 128 }
 129
 130 /*
 131  * Atomically swap in the new signal mask, and wait for a signal.
 132  */
 133 asmlinkage int
 134 sys_sigsuspend(old_sigset_t mask)
 135 {
 136         sigset_t blocked;
 137         siginitset(&blocked, mask);
 138         return sigsuspend(&blocked);
 139 }
 140
 141 asmlinkage int
 142 sys_sigaction(int sig, const struct old_sigaction __user *act,
 143               struct old_sigaction __user *oact)
 144 {
 145         struct k_sigaction new_ka, old_ka;
 146         int ret;
 147
 148         if (act) {
 149                 old_sigset_t mask;
 150                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
 151                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
 152                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
 153                     __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
 154                     __get_user(mask, &act->sa_mask))
 155                         return -EFAULT;
 156                 siginitset(&new_ka.sa.sa_mask, mask);
 157         }
 158
 159         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 160
 161         if (!ret && oact) {
 162                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
 163                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
 164                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
 165                     __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
 166                     __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
 167                         return -EFAULT;
 168         }
 169
 170         return ret;
 171 }
 172
 173 asmlinkage int
 174 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
 175                 unsigned long r4, unsigned long r5, unsigned long r6,
 176                 unsigned long r7,
 177                 struct pt_regs * regs)
 178 {
 179         return do_sigaltstack(uss, uoss, REF_REG_SP);
 180 }
 181
 182 /*
 183  * Do a signal return; undo the signal stack.
 184  */
 185 struct sigframe {
 186         struct sigcontext sc;
 187         unsigned long extramask[_NSIG_WORDS-1];
 188         long long retcode[2];
 189 };
 190
 191 struct rt_sigframe {
 192         struct siginfo __user *pinfo;
 193         void *puc;
 194         struct siginfo info;
 195         struct ucontext uc;
 196         long long retcode[2];
 197 };
 198
 199 #ifdef CONFIG_SH_FPU
 200 static inline int
 201 restore_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc)
 202 {
 203         int err = 0;
 204         int fpvalid;
 205
 206         err |= __get_user (fpvalid, &sc->sc_fpvalid);
 207         conditional_used_math(fpvalid);
 208         if (! fpvalid)
 209                 return err;
 210
 211         if (current == last_task_used_math) {
 212                 last_task_used_math = NULL;
 213                 regs->sr |= SR_FD;
 214         }
 215
 216         err |= __copy_from_user(&current->thread.xstate->hardfpu, &sc->sc_fpregs[0],
 217                                 (sizeof(long long) * 32) + (sizeof(int) * 1));
 218
 219         return err;
 220 }
 221
 222 static inline int
 223 setup_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc)
 224 {
 225         int err = 0;
 226         int fpvalid;
 227
 228         fpvalid = !!used_math();
 229         err |= __put_user(fpvalid, &sc->sc_fpvalid);
 230         if (! fpvalid)
 231                 return err;
 232
 233         if (current == last_task_used_math) {
 234                 enable_fpu();
 235                 save_fpu(current);
 236                 disable_fpu();
 237                 last_task_used_math = NULL;
 238                 regs->sr |= SR_FD;
 239         }
 240
 241         err |= __copy_to_user(&sc->sc_fpregs[0], &current->thread.xstate->hardfpu,
 242                               (sizeof(long long) * 32) + (sizeof(int) * 1));
 243         clear_used_math();
 244
 245         return err;
 246 }
 247 #else
 248 static inline int
 249 restore_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc)
 250 {
 251         return 0;
 252 }
 253 static inline int
 254 setup_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc)
 255 {
 256         return 0;
 257 }
 258 #endif
 259
 260 static int
 261 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, long long *r2_p)
 262 {
 263         unsigned int err = 0;
 264         unsigned long long current_sr, new_sr;
 265 #define SR_MASK 0xffff8cfd
 266
 267 #define COPY(x)         err |= __get_user(regs->x, &sc->sc_##x)
 268
 269         COPY(regs[0]);  COPY(regs[1]);  COPY(regs[2]);  COPY(regs[3]);
 270         COPY(regs[4]);  COPY(regs[5]);  COPY(regs[6]);  COPY(regs[7]);
 271         COPY(regs[8]);  COPY(regs[9]);  COPY(regs[10]); COPY(regs[11]);
 272         COPY(regs[12]); COPY(regs[13]); COPY(regs[14]); COPY(regs[15]);
 273         COPY(regs[16]); COPY(regs[17]); COPY(regs[18]); COPY(regs[19]);
 274         COPY(regs[20]); COPY(regs[21]); COPY(regs[22]); COPY(regs[23]);
 275         COPY(regs[24]); COPY(regs[25]); COPY(regs[26]); COPY(regs[27]);
 276         COPY(regs[28]); COPY(regs[29]); COPY(regs[30]); COPY(regs[31]);
 277         COPY(regs[32]); COPY(regs[33]); COPY(regs[34]); COPY(regs[35]);
 278         COPY(regs[36]); COPY(regs[37]); COPY(regs[38]); COPY(regs[39]);
 279         COPY(regs[40]); COPY(regs[41]); COPY(regs[42]); COPY(regs[43]);
 280         COPY(regs[44]); COPY(regs[45]); COPY(regs[46]); COPY(regs[47]);
 281         COPY(regs[48]); COPY(regs[49]); COPY(regs[50]); COPY(regs[51]);
 282         COPY(regs[52]); COPY(regs[53]); COPY(regs[54]); COPY(regs[55]);
 283         COPY(regs[56]); COPY(regs[57]); COPY(regs[58]); COPY(regs[59]);
 284         COPY(regs[60]); COPY(regs[61]); COPY(regs[62]);
 285         COPY(tregs[0]); COPY(tregs[1]); COPY(tregs[2]); COPY(tregs[3]);
 286         COPY(tregs[4]); COPY(tregs[5]); COPY(tregs[6]); COPY(tregs[7]);
 287
 288         /* Prevent the signal handler manipulating SR in a way that can
 289            crash the kernel. i.e. only allow S, Q, M, PR, SZ, FR to be
 290            modified */
 291         current_sr = regs->sr;
 292         err |= __get_user(new_sr, &sc->sc_sr);
 293         regs->sr &= SR_MASK;
 294         regs->sr |= (new_sr & ~SR_MASK);
 295
 296         COPY(pc);
 297
 298 #undef COPY
 299
 300         /* Must do this last in case it sets regs->sr.fd (i.e. after rest of sr
 301          * has been restored above.) */
 302         err |= restore_sigcontext_fpu(regs, sc);
 303
 304         regs->syscall_nr = -1;          /* disable syscall checks */
 305         err |= __get_user(*r2_p, &sc->sc_regs[REG_RET]);
 306         return err;
 307 }
 308
 309 asmlinkage int sys_sigreturn(unsigned long r2, unsigned long r3,
 310                                    unsigned long r4, unsigned long r5,
 311                                    unsigned long r6, unsigned long r7,
 312                                    struct pt_regs * regs)
 313 {
 314         struct sigframe __user *frame = (struct sigframe __user *) (long) REF_REG_SP;
 315         sigset_t set;
 316         long long ret;
 317
 318         /* Always make any pending restarted system calls return -EINTR */
 319         current_thread_info()->restart_block.fn = do_no_restart_syscall;
 320
 321         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 322                 goto badframe;
 323
 324         if (__get_user(set.sig[0], &frame->sc.oldmask)
 325             || (_NSIG_WORDS > 1
 326                 && __copy_from_user(&set.sig[1], &frame->extramask,
 327                                     sizeof(frame->extramask))))
 328                 goto badframe;
 329
 330         set_current_blocked(&set);
 331
 332         if (restore_sigcontext(regs, &frame->sc, &ret))
 333                 goto badframe;
 334         regs->pc -= 4;
 335
 336         return (int) ret;
 337
 338 badframe:
 339         force_sig(SIGSEGV, current);
 340         return 0;
 341 }
 342
 343 asmlinkage int sys_rt_sigreturn(unsigned long r2, unsigned long r3,
 344                                 unsigned long r4, unsigned long r5,
 345                                 unsigned long r6, unsigned long r7,
 346                                 struct pt_regs * regs)
 347 {
 348         struct rt_sigframe __user *frame = (struct rt_sigframe __user *) (long) REF_REG_SP;
 349         sigset_t set;
 350         stack_t __user st;
 351         long long ret;
 352
 353         /* Always make any pending restarted system calls return -EINTR */
 354         current_thread_info()->restart_block.fn = do_no_restart_syscall;
 355
 356         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 357                 goto badframe;
 358
 359         if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 360                 goto badframe;
 361
 362         set_current_blocked(&set);
 363
 364         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ret))
 365                 goto badframe;
 366         regs->pc -= 4;
 367
 368         if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
 369                 goto badframe;
 370         /* It is more difficult to avoid calling this function than to
 371            call it and ignore errors.  */
 372         do_sigaltstack(&st, NULL, REF_REG_SP);
 373
 374         return (int) ret;
 375
 376 badframe:
 377         force_sig(SIGSEGV, current);
 378         return 0;
 379 }
 380
 381 /*
 382  * Set up a signal frame.
 383  */
 384 static int
 385 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
 386                  unsigned long mask)
 387 {
 388         int err = 0;
 389
 390         /* Do this first, otherwise is this sets sr->fd, that value isn't preserved. */
 391         err |= setup_sigcontext_fpu(regs, sc);
 392
 393 #define COPY(x)         err |= __put_user(regs->x, &sc->sc_##x)
 394
 395         COPY(regs[0]);  COPY(regs[1]);  COPY(regs[2]);  COPY(regs[3]);
 396         COPY(regs[4]);  COPY(regs[5]);  COPY(regs[6]);  COPY(regs[7]);
 397         COPY(regs[8]);  COPY(regs[9]);  COPY(regs[10]); COPY(regs[11]);
 398         COPY(regs[12]); COPY(regs[13]); COPY(regs[14]); COPY(regs[15]);
 399         COPY(regs[16]); COPY(regs[17]); COPY(regs[18]); COPY(regs[19]);
 400         COPY(regs[20]); COPY(regs[21]); COPY(regs[22]); COPY(regs[23]);
 401         COPY(regs[24]); COPY(regs[25]); COPY(regs[26]); COPY(regs[27]);
 402         COPY(regs[28]); COPY(regs[29]); COPY(regs[30]); COPY(regs[31]);
 403         COPY(regs[32]); COPY(regs[33]); COPY(regs[34]); COPY(regs[35]);
 404         COPY(regs[36]); COPY(regs[37]); COPY(regs[38]); COPY(regs[39]);
 405         COPY(regs[40]); COPY(regs[41]); COPY(regs[42]); COPY(regs[43]);
 406         COPY(regs[44]); COPY(regs[45]); COPY(regs[46]); COPY(regs[47]);
 407         COPY(regs[48]); COPY(regs[49]); COPY(regs[50]); COPY(regs[51]);
 408         COPY(regs[52]); COPY(regs[53]); COPY(regs[54]); COPY(regs[55]);
 409         COPY(regs[56]); COPY(regs[57]); COPY(regs[58]); COPY(regs[59]);
 410         COPY(regs[60]); COPY(regs[61]); COPY(regs[62]);
 411         COPY(tregs[0]); COPY(tregs[1]); COPY(tregs[2]); COPY(tregs[3]);
 412         COPY(tregs[4]); COPY(tregs[5]); COPY(tregs[6]); COPY(tregs[7]);
 413         COPY(sr);       COPY(pc);
 414
 415 #undef COPY
 416
 417         err |= __put_user(mask, &sc->oldmask);
 418
 419         return err;
 420 }
 421
 422 /*
 423  * Determine which stack to use..
 424  */
 425 static inline void __user *
 426 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
 427 {
 428         if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
 429                 sp = current->sas_ss_sp + current->sas_ss_size;
 430
 431         return (void __user *)((sp - frame_size) & -8ul);
 432 }
 433
 434 void sa_default_restorer(void);         /* See comments below */
 435 void sa_default_rt_restorer(void);      /* See comments below */
 436
 437 static int setup_frame(int sig, struct k_sigaction *ka,
 438                        sigset_t *set, struct pt_regs *regs)
 439 {
 440         struct sigframe __user *frame;
 441         int err = 0;
 442         int signal;
 443
 444         frame = get_sigframe(ka, regs->regs[REG_SP], sizeof(*frame));
 445
 446         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 447                 goto give_sigsegv;
 448
 449         signal = current_thread_info()->exec_domain
 450                 && current_thread_info()->exec_domain->signal_invmap
 451                 && sig < 32
 452                 ? current_thread_info()->exec_domain->signal_invmap[sig]
 453                 : sig;
 454
 455         err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
 456
 457         /* Give up earlier as i386, in case */
 458         if (err)
 459                 goto give_sigsegv;
 460
 461         if (_NSIG_WORDS > 1) {
 462                 err |= __copy_to_user(frame->extramask, &set->sig[1],
 463                                       sizeof(frame->extramask)); }
 464
 465         /* Give up earlier as i386, in case */
 466         if (err)
 467                 goto give_sigsegv;
 468
 469         /* Set up to return from userspace.  If provided, use a stub
 470            already in userspace.  */
 471         if (ka->sa.sa_flags & SA_RESTORER) {
 472                 /*
 473                  * On SH5 all edited pointers are subject to NEFF
 474                  */
 475                 DEREF_REG_PR = neff_sign_extend((unsigned long)
 476                         ka->sa.sa_restorer | 0x1);
 477         } else {
 478                 /*
 479                  * Different approach on SH5.
 480                  * . Endianness independent asm code gets placed in entry.S .
 481                  *   This is limited to four ASM instructions corresponding
 482                  *   to two long longs in size.
 483                  * . err checking is done on the else branch only
 484                  * . flush_icache_range() is called upon __put_user() only
 485                  * . all edited pointers are subject to NEFF
 486                  * . being code, linker turns ShMedia bit on, always
 487                  *   dereference index -1.
 488                  */
 489                 DEREF_REG_PR = neff_sign_extend((unsigned long)
 490                         frame->retcode | 0x01);
 491
 492                 if (__copy_to_user(frame->retcode,
 493                         (void *)((unsigned long)sa_default_restorer & (~1)), 16) != 0)
 494                         goto give_sigsegv;
 495
 496                 /* Cohere the trampoline with the I-cache. */
 497                 flush_cache_sigtramp(DEREF_REG_PR-1);
 498         }
 499
 500         /*
 501          * Set up registers for signal handler.
 502          * All edited pointers are subject to NEFF.
 503          */
 504         regs->regs[REG_SP] = neff_sign_extend((unsigned long)frame);
 505         regs->regs[REG_ARG1] = signal; /* Arg for signal handler */
 506
 507         /* FIXME:
 508            The glibc profiling support for SH-5 needs to be passed a sigcontext
 509            so it can retrieve the PC.  At some point during 2003 the glibc
 510            support was changed to receive the sigcontext through the 2nd
 511            argument, but there are still versions of libc.so in use that use
 512            the 3rd argument.  Until libc.so is stabilised, pass the sigcontext
 513            through both 2nd and 3rd arguments.
 514         */
 515
 516         regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->sc;
 517         regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->sc;
 518
 519         regs->pc = neff_sign_extend((unsigned long)ka->sa.sa_handler);
 520
 521         set_fs(USER_DS);
 522
 523         /* Broken %016Lx */
 524         pr_debug("SIG deliver (#%d,%s:%d): sp=%p pc=%08Lx%08Lx link=%08Lx%08Lx\n",
 525                  signal, current->comm, current->pid, frame,
 526                  regs->pc >> 32, regs->pc & 0xffffffff,
 527                  DEREF_REG_PR >> 32, DEREF_REG_PR & 0xffffffff);
 528
 529         return 0;
 530
 531 give_sigsegv:
 532         force_sigsegv(sig, current);
 533         return -EFAULT;
 534 }
 535
 536 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 537                           sigset_t *set, struct pt_regs *regs)
 538 {
 539         struct rt_sigframe __user *frame;
 540         int err = 0;
 541         int signal;
 542
 543         frame = get_sigframe(ka, regs->regs[REG_SP], sizeof(*frame));
 544
 545         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 546                 goto give_sigsegv;
 547
 548         signal = current_thread_info()->exec_domain
 549                 && current_thread_info()->exec_domain->signal_invmap
 550                 && sig < 32
 551                 ? current_thread_info()->exec_domain->signal_invmap[sig]
 552                 : sig;
 553
 554         err |= __put_user(&frame->info, &frame->pinfo);
 555         err |= __put_user(&frame->uc, &frame->puc);
 556         err |= copy_siginfo_to_user(&frame->info, info);
 557
 558         /* Give up earlier as i386, in case */
 559         if (err)
 560                 goto give_sigsegv;
 561
 562         /* Create the ucontext.  */
 563         err |= __put_user(0, &frame->uc.uc_flags);
 564         err |= __put_user(0, &frame->uc.uc_link);
 565         err |= __put_user((void *)current->sas_ss_sp,
 566                           &frame->uc.uc_stack.ss_sp);
 567         err |= __put_user(sas_ss_flags(regs->regs[REG_SP]),
 568                           &frame->uc.uc_stack.ss_flags);
 569         err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
 570         err |= setup_sigcontext(&frame->uc.uc_mcontext,
 571                                 regs, set->sig[0]);
 572         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 573
 574         /* Give up earlier as i386, in case */
 575         if (err)
 576                 goto give_sigsegv;
 577
 578         /* Set up to return from userspace.  If provided, use a stub
 579            already in userspace.  */
 580         if (ka->sa.sa_flags & SA_RESTORER) {
 581                 /*
 582                  * On SH5 all edited pointers are subject to NEFF
 583                  */
 584                 DEREF_REG_PR = neff_sign_extend((unsigned long)
 585                         ka->sa.sa_restorer | 0x1);
 586         } else {
 587                 /*
 588                  * Different approach on SH5.
 589                  * . Endianness independent asm code gets placed in entry.S .
 590                  *   This is limited to four ASM instructions corresponding
 591                  *   to two long longs in size.
 592                  * . err checking is done on the else branch only
 593                  * . flush_icache_range() is called upon __put_user() only
 594                  * . all edited pointers are subject to NEFF
 595                  * . being code, linker turns ShMedia bit on, always
 596                  *   dereference index -1.
 597                  */
 598                 DEREF_REG_PR = neff_sign_extend((unsigned long)
 599                         frame->retcode | 0x01);
 600
 601                 if (__copy_to_user(frame->retcode,
 602                         (void *)((unsigned long)sa_default_rt_restorer & (~1)), 16) != 0)
 603                         goto give_sigsegv;
 604
 605                 /* Cohere the trampoline with the I-cache. */
 606                 flush_icache_range(DEREF_REG_PR-1, DEREF_REG_PR-1+15);
 607         }
 608
 609         /*
 610          * Set up registers for signal handler.
 611          * All edited pointers are subject to NEFF.
 612          */
 613         regs->regs[REG_SP] = neff_sign_extend((unsigned long)frame);
 614         regs->regs[REG_ARG1] = signal; /* Arg for signal handler */
 615         regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->info;
 616         regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->uc.uc_mcontext;
 617         regs->pc = neff_sign_extend((unsigned long)ka->sa.sa_handler);
 618
 619         set_fs(USER_DS);
 620
 621         pr_debug("SIG deliver (#%d,%s:%d): sp=%p pc=%08Lx%08Lx link=%08Lx%08Lx\n",
 622                  signal, current->comm, current->pid, frame,
 623                  regs->pc >> 32, regs->pc & 0xffffffff,
 624                  DEREF_REG_PR >> 32, DEREF_REG_PR & 0xffffffff);
 625
 626         return 0;
 627
 628 give_sigsegv:
 629         force_sigsegv(sig, current);
 630         return -EFAULT;
 631 }
 632
 633 /*
 634  * OK, we're invoking a handler
 635  */
 636 static void
 637 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 638                 struct pt_regs * regs)
 639 {
 640         sigset_t *oldset = sigmask_to_save();
 641         int ret;
 642
 643         /* Set up the stack frame */
 644         if (ka->sa.sa_flags & SA_SIGINFO)
 645                 ret = setup_rt_frame(sig, ka, info, oldset, regs);
 646         else
 647                 ret = setup_frame(sig, ka, oldset, regs);
 648
 649         if (ret)
 650                 return;
 651
 652         signal_delivered(sig, info, ka, regs,
 653                         test_thread_flag(TIF_SINGLESTEP));
 654 }
 655
 656 asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
 657 {
 658         if (thread_info_flags & _TIF_SIGPENDING)
 659                 do_signal(regs);
 660
 661         if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 662                 clear_thread_flag(TIF_NOTIFY_RESUME);
 663                 tracehook_notify_resume(regs);
 664         }
 665 }