/*
 * Architecture-specific signal handling support.
 *
 * Copyright (C) 1999-2002 Hewlett-Packard Co
 *      David Mosberger-Tang <davidm@hpl.hp.com>
 *
 * Derived from i386 and Alpha versions.
 */

#include <linux/config.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/wait.h>

#include <asm/ia32.h>
#include <asm/uaccess.h>
#include <asm/rse.h>
#include <asm/sigcontext.h>

#include "sigframe.h"

#define DEBUG_SIG       0
#define STACK_ALIGN     16              /* minimal alignment for stack pointer */
#define _BLOCKABLE      (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

#if _NSIG_WORDS > 1
# define PUT_SIGSET(k,u)        __copy_to_user((u)->sig, (k)->sig, sizeof(sigset_t))
# define GET_SIGSET(k,u)        __copy_from_user((k)->sig, (u)->sig, sizeof(sigset_t))
#else
# define PUT_SIGSET(k,u)        __put_user((k)->sig[0], &(u)->sig[0])
# define GET_SIGSET(k,u)        __get_user((k)->sig[0], &(u)->sig[0])
#endif

extern long ia64_do_signal (sigset_t *, struct sigscratch *, long);     /* forward decl */

register double f16 asm ("f16"); register double f17 asm ("f17");
register double f18 asm ("f18"); register double f19 asm ("f19");
register double f20 asm ("f20"); register double f21 asm ("f21");
register double f22 asm ("f22"); register double f23 asm ("f23");

register double f24 asm ("f24"); register double f25 asm ("f25");
register double f26 asm ("f26"); register double f27 asm ("f27");
register double f28 asm ("f28"); register double f29 asm ("f29");
register double f30 asm ("f30"); register double f31 asm ("f31");

long
ia64_rt_sigsuspend (sigset_t *uset, size_t sigsetsize, struct sigscratch *scr)
{
        sigset_t oldset, set;

        /* XXX: Don't preclude handling different sized sigset_t's.  */
        if (sigsetsize != sizeof(sigset_t))
                return -EINVAL;

        if (!access_ok(VERIFY_READ, uset, sigsetsize))
                return -EFAULT;

        if (GET_SIGSET(&set, uset))
                return -EFAULT;

        sigdelsetmask(&set, ~_BLOCKABLE);

        spin_lock_irq(&current->sigmask_lock);
        {
                oldset = current->blocked;
                current->blocked = set;
                recalc_sigpending(current);
        }
        spin_unlock_irq(&current->sigmask_lock);

        /*
         * The return below usually returns to the signal handler.  We need to
         * pre-set the correct error code here to ensure that the right values
         * get saved in sigcontext by ia64_do_signal.
         */
        scr->pt.r8 = EINTR;
        scr->pt.r10 = -1;

        while (1) {
                current->state = TASK_INTERRUPTIBLE;
                schedule();
                if (ia64_do_signal(&oldset, scr, 1))
                        return -EINTR;
        }
}

asmlinkage long
sys_sigaltstack (const stack_t *uss, stack_t *uoss, long arg2, long arg3, long arg4,
                 long arg5, long arg6, long arg7, long stack)
{
        struct pt_regs *pt = (struct pt_regs *) &stack;

        return do_sigaltstack(uss, uoss, pt->r12);
}

static long
restore_sigcontext (struct sigcontext *sc, struct sigscratch *scr)
{
        unsigned long ip, flags, nat, um, cfm;
        long err;

        /* restore scratch that always needs gets updated during signal delivery: */
        err = __get_user(flags, &sc->sc_flags);

        err |= __get_user(nat, &sc->sc_nat);
        err |= __get_user(ip, &sc->sc_ip);                      /* instruction pointer */
        err |= __get_user(cfm, &sc->sc_cfm);
        err |= __get_user(um, &sc->sc_um);                      /* user mask */
        err |= __get_user(scr->pt.ar_rsc, &sc->sc_ar_rsc);
        err |= __get_user(scr->pt.ar_unat, &sc->sc_ar_unat);
        err |= __get_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr);
        err |= __get_user(scr->pt.ar_pfs, &sc->sc_ar_pfs);
        err |= __get_user(scr->pt.pr, &sc->sc_pr);              /* predicates */
        err |= __get_user(scr->pt.b0, &sc->sc_br[0]);           /* b0 (rp) */
        err |= __copy_from_user(&scr->pt.r1, &sc->sc_gr[1], 8); /* r1 */
        err |= __copy_from_user(&scr->pt.r8, &sc->sc_gr[8], 4*8);       /* r8-r11 */
        err |= __copy_from_user(&scr->pt.r12, &sc->sc_gr[12], 2*8);     /* r12-r13 */
        err |= __copy_from_user(&scr->pt.r15, &sc->sc_gr[15], 8);       /* r15 */
        
        if ((flags & IA64_SC_FLAG_IN_SYSCALL)==0)
        {
                // Only get user sig context when not in syscall. 
                err |= __get_user(scr->pt.ar_ccv, &sc->sc_ar_ccv);
                err |= __get_user(scr->pt.ar_csd, &sc->sc_ar25);        /* ar.csd */
                err |= __get_user(scr->pt.ar_ssd, &sc->sc_ar26);        /* ar.ssd */
                err |= __get_user(scr->pt.b6, &sc->sc_br[6]);           /* b6 */
                err |= __get_user(scr->pt.b7, &sc->sc_br[7]);           /* b7 */
                err |= __copy_from_user(&scr->pt.r2, &sc->sc_gr[2], 2*8);       /* r2-r3 */
                err |= __copy_from_user(&scr->pt.r14, &sc->sc_gr[14], 8);       /* r14 */
                err |= __copy_from_user(&scr->pt.r16, &sc->sc_gr[16], 16*8);    /* r16-r31 */
        }

        scr->pt.cr_ifs = cfm | (1UL << 63);

        /* establish new instruction pointer: */
        scr->pt.cr_iip = ip & ~0x3UL;
        ia64_psr(&scr->pt)->ri = ip & 0x3;
        scr->pt.cr_ipsr = (scr->pt.cr_ipsr & ~IA64_PSR_UM) | (um & IA64_PSR_UM);

        scr->scratch_unat = ia64_put_scratch_nat_bits(&scr->pt, nat);

        if ((flags & IA64_SC_FLAG_FPH_VALID) != 0) {
                struct ia64_psr *psr = ia64_psr(&scr->pt);

                __copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16);
                psr->mfh = 0;   /* drop signal handler's fph contents... */
                if (psr->dfh)
                        ia64_drop_fpu(current);
                else {
                        /* We already own the local fph, otherwise psr->dfh wouldn't be 0.  */
                        __ia64_load_fpu(current->thread.fph);
                        ia64_set_local_fpu_owner(current);
                }
        }
        return err;
}

int
copy_siginfo_to_user (siginfo_t *to, siginfo_t *from)
{
        if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t)))
                return -EFAULT;
        if (from->si_code < 0) {
                if (__copy_to_user(to, from, sizeof(siginfo_t)))
                        return -EFAULT;
                return 0;
        } else {
                int err;

                /*
                 * If you change siginfo_t structure, please be sure
                 * this code is fixed accordingly.  It should never
                 * copy any pad contained in the structure to avoid
                 * security leaks, but must copy the generic 3 ints
                 * plus the relevant union member.
                 */
                err = __put_user(from->si_signo, &to->si_signo);
                err |= __put_user(from->si_errno, &to->si_errno);
                err |= __put_user((short)from->si_code, &to->si_code);
                switch (from->si_code >> 16) {
                      case __SI_FAULT >> 16:
                        err |= __put_user(from->si_flags, &to->si_flags);
                        err |= __put_user(from->si_isr, &to->si_isr);
                      case __SI_POLL >> 16:
                        err |= __put_user(from->si_addr, &to->si_addr);
                        err |= __put_user(from->si_imm, &to->si_imm);
                        break;
                      case __SI_CHLD >> 16:
                        err |= __put_user(from->si_utime, &to->si_utime);
                        err |= __put_user(from->si_stime, &to->si_stime);
                        err |= __put_user(from->si_status, &to->si_status);
                      case __SI_PROF >> 16:
                        err |= __put_user(from->si_uid, &to->si_uid);
                        err |= __put_user(from->si_pid, &to->si_pid);
                        if (from->si_code == PROF_OVFL) {
                                err |= __put_user(from->si_pfm_ovfl[0], &to->si_pfm_ovfl[0]);
                                err |= __put_user(from->si_pfm_ovfl[1], &to->si_pfm_ovfl[1]);
                                err |= __put_user(from->si_pfm_ovfl[2], &to->si_pfm_ovfl[2]);
                                err |= __put_user(from->si_pfm_ovfl[3], &to->si_pfm_ovfl[3]);
                        }
                        break;
                      default:
                        err |= __put_user(from->si_uid, &to->si_uid);
                        err |= __put_user(from->si_pid, &to->si_pid);
                        break;
                      /* case __SI_RT: This is not generated by the kernel as of now.  */
                }
                return err;
        }
}

int
copy_siginfo_from_user (siginfo_t *to, siginfo_t *from)
{
        if (!access_ok(VERIFY_READ, from, sizeof(siginfo_t)))
                return -EFAULT;
        if (__copy_from_user(to, from, sizeof(siginfo_t)) != 0)
                return -EFAULT;

        if (SI_FROMUSER(to))
                return 0;

        to->si_code &= ~__SI_MASK;
        if (to->si_code != 0) {
                switch (to->si_signo) {
                      case SIGILL: case SIGFPE: case SIGSEGV: case SIGBUS: case SIGTRAP:
                        to->si_code |= __SI_FAULT;
                        break;

                      case SIGCHLD:
                        to->si_code |= __SI_CHLD;
                        break;

                      case SIGPOLL:
                        to->si_code |= __SI_POLL;
                        break;

                      case SIGPROF:
                        to->si_code |= __SI_PROF;
                        break;

                      default:
                        break;
                }
        }
        return 0;
}

long
ia64_rt_sigreturn (struct sigscratch *scr)
{
        extern char ia64_strace_leave_kernel, ia64_leave_kernel;
        struct sigcontext *sc;
        struct siginfo si;
        sigset_t set;
        long retval;

        sc = &((struct sigframe *) (scr->pt.r12 + 16))->sc;

        /*
         * When we return to the previously executing context, r8 and r10 have already
         * been setup the way we want them.  Indeed, if the signal wasn't delivered while
         * in a system call, we must not touch r8 or r10 as otherwise user-level state
         * could be corrupted.
         */
        retval = (long) &ia64_leave_kernel;
        if (current->ptrace & PT_TRACESYS)
                /*
                 * strace expects to be notified after sigreturn returns even though the
                 * context to which we return may not be in the middle of a syscall.
                 * Thus, the return-value that strace displays for sigreturn is
                 * meaningless.
                 */
                retval = (long) &ia64_strace_leave_kernel;

        if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
                goto give_sigsegv;

        if (GET_SIGSET(&set, &sc->sc_mask))
                goto give_sigsegv;

        sigdelsetmask(&set, ~_BLOCKABLE);

        spin_lock_irq(&current->sigmask_lock);
        {
                current->blocked = set;
                recalc_sigpending(current);
        }
        spin_unlock_irq(&current->sigmask_lock);

        if (restore_sigcontext(sc, scr))
                goto give_sigsegv;

#if DEBUG_SIG
        printk("SIG return (%s:%d): sp=%lx ip=%lx\n",
               current->comm, current->pid, scr->pt.r12, scr->pt.cr_iip);
#endif
        /*
         * It is more difficult to avoid calling this function than to
         * call it and ignore errors.
         */
        do_sigaltstack(&sc->sc_stack, 0, scr->pt.r12);
        return retval;

  give_sigsegv:
        si.si_signo = SIGSEGV;
        si.si_errno = 0;
        si.si_code = SI_KERNEL;
        si.si_pid = current->pid;
        si.si_uid = current->uid;
        si.si_addr = sc;
        force_sig_info(SIGSEGV, &si, current);
        return retval;
}

/*
 * This does just the minimum required setup of sigcontext.
 * Specifically, it only installs data that is either not knowable at
 * the user-level or that gets modified before execution in the
 * trampoline starts.  Everything else is done at the user-level.
 */
static long
setup_sigcontext (struct sigcontext *sc, sigset_t *mask, struct sigscratch *scr)
{
        unsigned long flags = 0, ifs, cfm, nat;
        long err;

        ifs = scr->pt.cr_ifs;

        if (on_sig_stack((unsigned long) sc))
                flags |= IA64_SC_FLAG_ONSTACK;
        if ((ifs & (1UL << 63)) == 0) {
                /* if cr_ifs isn't valid, we got here through a syscall */
                flags |= IA64_SC_FLAG_IN_SYSCALL;
                cfm = scr->ar_pfs & ((1UL << 38) - 1);
        } else
                cfm = ifs & ((1UL << 38) - 1);
        ia64_flush_fph(current);
        if ((current->thread.flags & IA64_THREAD_FPH_VALID)) {
                flags |= IA64_SC_FLAG_FPH_VALID;
                __copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16);
        }

        nat = ia64_get_scratch_nat_bits(&scr->pt, scr->scratch_unat);

        err  = __put_user(flags, &sc->sc_flags);

        err |= __put_user(nat, &sc->sc_nat);
        err |= PUT_SIGSET(mask, &sc->sc_mask);
        err |= __put_user(cfm, &sc->sc_cfm);
        err |= __put_user(scr->pt.cr_ipsr & IA64_PSR_UM, &sc->sc_um);
        err |= __put_user(scr->pt.ar_rsc, &sc->sc_ar_rsc);
        err |= __put_user(scr->pt.ar_unat, &sc->sc_ar_unat);            /* ar.unat */
        err |= __put_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr);            /* ar.fpsr */
        err |= __put_user(scr->pt.ar_pfs, &sc->sc_ar_pfs);
        err |= __put_user(scr->pt.pr, &sc->sc_pr);                      /* predicates */
        err |= __put_user(scr->pt.b0, &sc->sc_br[0]);                   /* b0 (rp) */
        err |= __copy_to_user(&sc->sc_gr[1], &scr->pt.r1, 8);           /* r1 */
        err |= __copy_to_user(&sc->sc_gr[8], &scr->pt.r8, 4*8);         /* r8-r11 */
        err |= __copy_to_user(&sc->sc_gr[12], &scr->pt.r12, 2*8);       /* r12-r13 */
        err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8);         /* r15 */
        err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip);

        if (flags & IA64_SC_FLAG_IN_SYSCALL)
        {
                // Clear scratch registers in sig context for asynchronized signal.
                err |= __clear_user(&sc->sc_ar_ccv, 8);
                err |= __clear_user(&sc->sc_ar25,8);                            /* ar.csd */
                err |= __clear_user(&sc->sc_ar26,8);                            /* ar.ssd */
                err |= __clear_user(&sc->sc_br[6],8);                           /* b6 */
                err |= __clear_user(&sc->sc_br[7],8);                           /* b7 */

                err |= __clear_user(&sc->sc_gr[2], 2*8);                        /* r2-r3 */
                err |= __clear_user(&sc->sc_gr[14],8);                          /* r14 */
                err |= __clear_user(&sc->sc_gr[16],16*8);                       /* r16-r31 */
        } else
        {
                // Copy scratch registers in sig context from pt_regs for synchronized signal.
                err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv);
                err |= __put_user(scr->pt.ar_csd, &sc->sc_ar25);                /* ar.csd */
                err |= __put_user(scr->pt.ar_ssd, &sc->sc_ar26);                /* ar.ssd */
                err |= __put_user(scr->pt.b6, &sc->sc_br[6]);                   /* b6 */
                err |= __put_user(scr->pt.b7, &sc->sc_br[7]);                   /* b7 */

                err |= __copy_to_user(&sc->sc_gr[2], &scr->pt.r2, 2*8);         /* r2-r3 */
                err |= __copy_to_user(&sc->sc_gr[14], &scr->pt.r14, 8);         /* r14 */
                err |= __copy_to_user(&sc->sc_gr[16], &scr->pt.r16, 16*8);      /* r16-r31 */
        }
        return err;
}

/*
 * Check whether the register-backing store is already on the signal stack.
 */
static inline int
rbs_on_sig_stack (unsigned long bsp)
{
        return (bsp - current->sas_ss_sp < current->sas_ss_size);
}

static long
setup_frame (int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set,
             struct sigscratch *scr)
{
        extern char ia64_sigtramp[], __start_gate_section[];
        unsigned long tramp_addr, new_rbs = 0;
        struct sigframe *frame;
        struct siginfo si;
        long err;

        frame = (void *) scr->pt.r12;
        tramp_addr = GATE_ADDR + (ia64_sigtramp - __start_gate_section);
        if ((ka->sa.sa_flags & SA_ONSTACK) && sas_ss_flags((unsigned long) frame) == 0) {
                frame = (void *) ((current->sas_ss_sp + current->sas_ss_size)
                                  & ~(STACK_ALIGN - 1));
                /*
                 * We need to check for the register stack being on the signal stack
                 * separately, because it's switched separately (memory stack is switched
                 * in the kernel, register stack is switched in the signal trampoline).
                 */
                if (!rbs_on_sig_stack(scr->pt.ar_bspstore))
                        new_rbs  = (current->sas_ss_sp + sizeof(long) - 1) & ~(sizeof(long) - 1);
        }
        frame = (void *) frame - ((sizeof(*frame) + STACK_ALIGN - 1) & ~(STACK_ALIGN - 1));

        if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
                goto give_sigsegv;

        err  = __put_user(sig, &frame->arg0);
        err |= __put_user(&frame->info, &frame->arg1);
        err |= __put_user(&frame->sc, &frame->arg2);
        err |= __put_user(new_rbs, &frame->sc.sc_rbs_base);
        err |= __put_user(0, &frame->sc.sc_loadrs);     /* initialize to zero */
        err |= __put_user(ka->sa.sa_handler, &frame->handler);

        err |= copy_siginfo_to_user(&frame->info, info);

        err |= __put_user(current->sas_ss_sp, &frame->sc.sc_stack.ss_sp);
        err |= __put_user(current->sas_ss_size, &frame->sc.sc_stack.ss_size);
        err |= __put_user(sas_ss_flags(scr->pt.r12), &frame->sc.sc_stack.ss_flags);
        err |= setup_sigcontext(&frame->sc, set, scr);

        if (err)
                goto give_sigsegv;

        scr->pt.r12 = (unsigned long) frame - 16;       /* new stack pointer */
        scr->pt.ar_fpsr = FPSR_DEFAULT;                 /* reset fpsr for signal handler */
        scr->pt.cr_iip = tramp_addr;
        ia64_psr(&scr->pt)->ri = 0;                     /* start executing in first slot */
        /*
         * Force the interruption function mask to zero.  This has no effect when a
         * system-call got interrupted by a signal (since, in that case, scr->pt_cr_ifs is
         * ignored), but it has the desirable effect of making it possible to deliver a
         * signal with an incomplete register frame (which happens when a mandatory RSE
         * load faults).  Furthermore, it has no negative effect on the getting the user's
         * dirty partition preserved, because that's governed by scr->pt.loadrs.
         */
        scr->pt.cr_ifs = (1UL << 63);

        /*
         * Note: this affects only the NaT bits of the scratch regs (the ones saved in
         * pt_regs), which is exactly what we want.
         */
        scr->scratch_unat = 0; /* ensure NaT bits of r12 is clear */

#if DEBUG_SIG
        printk("SIG deliver (%s:%d): sig=%d sp=%lx ip=%lx handler=%lx\n",
               current->comm, current->pid, sig, scr->pt.r12, scr->pt.cr_iip, scr->pt.r3);
#endif
        return 1;

  give_sigsegv:
        if (sig == SIGSEGV)
                ka->sa.sa_handler = SIG_DFL;
        si.si_signo = SIGSEGV;
        si.si_errno = 0;
        si.si_code = SI_KERNEL;
        si.si_pid = current->pid;
        si.si_uid = current->uid;
        si.si_addr = frame;
        force_sig_info(SIGSEGV, &si, current);
        return 0;
}

static long
handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset,
               struct sigscratch *scr)
{
#ifdef CONFIG_IA32_SUPPORT
        if (IS_IA32_PROCESS(&scr->pt)) {
                /* send signal to IA-32 process */
                if (!ia32_setup_frame1(sig, ka, info, oldset, &scr->pt))
                        return 0;
        } else
#endif
        /* send signal to IA-64 process */
        if (!setup_frame(sig, ka, info, oldset, scr))
                return 0;

        if (ka->sa.sa_flags & SA_ONESHOT)
                ka->sa.sa_handler = SIG_DFL;

        if (!(ka->sa.sa_flags & SA_NODEFER)) {
                spin_lock_irq(&current->sigmask_lock);
                {
                        sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
                        sigaddset(&current->blocked, sig);
                        recalc_sigpending(current);
                }
                spin_unlock_irq(&current->sigmask_lock);
        }
        return 1;
}

/*
 * Note that `init' is a special process: it doesn't get signals it doesn't want to
 * handle.  Thus you cannot kill init even with a SIGKILL even by mistake.
 */
long
ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
{
        struct signal_struct *sig;
        struct k_sigaction *ka;
        siginfo_t info;
        long restart = in_syscall;
        long errno = scr->pt.r8;

        /*
         * In the ia64_leave_kernel code path, we want the common case to go fast, which
         * is why we may in certain cases get here from kernel mode. Just return without
         * doing anything if so.
         */
        if (!user_mode(&scr->pt))
                return 0;

        if (!oldset)
                oldset = &current->blocked;

#ifdef CONFIG_IA32_SUPPORT
        if (IS_IA32_PROCESS(&scr->pt)) {
                if (in_syscall) {
                        if (errno >= 0)
                                restart = 0;
                        else
                                errno = -errno;
                }
        } else
#endif
        if (scr->pt.r10 != -1) {
                /*
                 * A system calls has to be restarted only if one of the error codes
                 * ERESTARTNOHAND, ERESTARTSYS, or ERESTARTNOINTR is returned.  If r10
                 * isn't -1 then r8 doesn't hold an error code and we don't need to
                 * restart the syscall, so we can clear the "restart" flag here.
                 */
                restart = 0;
        }

        for (;;) {
                unsigned long signr;

                spin_lock_irq(&current->sigmask_lock);
                signr = dequeue_signal(&current->blocked, &info);
                spin_unlock_irq(&current->sigmask_lock);

                if (!signr)
                        break;

                if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
                        /* Let the debugger run.  */
                        current->exit_code = signr;
                        current->thread.siginfo = &info;
                        current->state = TASK_STOPPED;
                        notify_parent(current, SIGCHLD);
                        schedule();

                        signr = current->exit_code;
                        current->thread.siginfo = 0;

                        /* We're back.  Did the debugger cancel the sig?  */
                        if (!signr)
                                continue;
                        current->exit_code = 0;

                        /* The debugger continued.  Ignore SIGSTOP.  */
                        if (signr == SIGSTOP)
                                continue;

                        /* Update the siginfo structure.  Is this good?  */
                        if (signr != info.si_signo) {
                                info.si_signo = signr;
                                info.si_errno = 0;
                                info.si_code = SI_USER;
                                info.si_pid = current->p_pptr->pid;
                                info.si_uid = current->p_pptr->uid;
                        }

                        /* If the (new) signal is now blocked, requeue it.  */
                        if (sigismember(&current->blocked, signr)) {
                                send_sig_info(signr, &info, current);
                                continue;
                        }
                }

                ka = &current->sig->action[signr - 1];
                if (ka->sa.sa_handler == SIG_IGN) {
                        if (signr != SIGCHLD)
                                continue;
                        /* Check for SIGCHLD: it's special.  */
                        while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
                                /* nothing */;
                        continue;
                }

                if (ka->sa.sa_handler == SIG_DFL) {
                        int exit_code = signr;

                        /* Init gets no signals it doesn't want.  */
                        if (current->pid == 1)
                                continue;

                        switch (signr) {
                              case SIGCONT: case SIGCHLD: case SIGWINCH: case SIGURG:
                                continue;

                              case SIGTSTP: case SIGTTIN: case SIGTTOU:
                                if (is_orphaned_pgrp(current->pgrp))
                                        continue;
                                /* FALLTHRU */

                              case SIGSTOP:
                                current->state = TASK_STOPPED;
                                current->exit_code = signr;
                                sig = current->p_pptr->sig;
                                if (sig && !(sig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP))
                                        notify_parent(current, SIGCHLD);
                                schedule();
                                continue;

                              case SIGQUIT: case SIGILL: case SIGTRAP:
                              case SIGABRT: case SIGFPE: case SIGSEGV:
                              case SIGBUS: case SIGSYS: case SIGXCPU: case SIGXFSZ:
                                if (do_coredump(signr, &scr->pt))
                                        exit_code |= 0x80;
                                /* FALLTHRU */

                              default:
                                sig_exit(signr, exit_code, &info);
                                /* NOTREACHED */
                        }
                }

                if (restart) {
                        switch (errno) {
                              case ERESTARTSYS:
                                if ((ka->sa.sa_flags & SA_RESTART) == 0) {
                              case ERESTARTNOHAND:
#ifdef CONFIG_IA32_SUPPORT
                                        if (IS_IA32_PROCESS(&scr->pt))
                                                scr->pt.r8 = -EINTR;
                                        else
#endif
                                        scr->pt.r8 = EINTR;
                                        /* note: scr->pt.r10 is already -1 */
                                        break;
                                }
                              case ERESTARTNOINTR:
#ifdef CONFIG_IA32_SUPPORT
                                if (IS_IA32_PROCESS(&scr->pt)) {
                                        scr->pt.r8 = scr->pt.r1;
                                        scr->pt.cr_iip -= 2;
                                } else
#endif
                                ia64_decrement_ip(&scr->pt);
                        }
                }

                /* Whee!  Actually deliver the signal.  If the
                   delivery failed, we need to continue to iterate in
                   this loop so we can deliver the SIGSEGV... */
                if (handle_signal(signr, ka, &info, oldset, scr))
                        return 1;
        }

        /* Did we come from a system call? */
        if (restart) {
                /* Restart the system call - no handlers present */
                if (errno == ERESTARTNOHAND || errno == ERESTARTSYS || errno == ERESTARTNOINTR) {
#ifdef CONFIG_IA32_SUPPORT
                        if (IS_IA32_PROCESS(&scr->pt)) {
                                scr->pt.r8 = scr->pt.r1;
                                scr->pt.cr_iip -= 2;
                        } else
#endif
                        /*
                         * Note: the syscall number is in r15 which is
                         * saved in pt_regs so all we need to do here
                         * is adjust ip so that the "break"
                         * instruction gets re-executed.
                         */
                        ia64_decrement_ip(&scr->pt);
                }
        }
        return 0;
}