goto badframe;	regs->gpr[1] = newsp;	regs->gpr[6] = (unsigned long) rt_sf;	regs->link = (unsigned long) frame->tramp;	return;badframe:#if DEBUG_SIG	printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",	       regs, frame, newsp);#endif	do_exit(SIGSEGV);}/* * Do a signal return; undo the signal stack. */int sys_sigreturn(struct pt_regs *regs){	struct sigcontext_struct *sc, sigctx;	struct sigregs *sr;	int ret;	elf_gregset_t saved_regs;  /* an array of ELF_NGREG unsigned longs */	sigset_t set;	unsigned long prevsp;	sc = (struct sigcontext_struct *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))		goto badframe;	set.sig[0] = sigctx.oldmask;#if _NSIG_WORDS > 1	set.sig[1] = sigctx._unused[3];#endif	sigdelsetmask(&set, ~_BLOCKABLE);	spin_lock_irq(&current->sigmask_lock);	current->blocked = set;	recalc_sigpending(current);	spin_unlock_irq(&current->sigmask_lock);	if (regs->msr & MSR_FP )		giveup_fpu(current);	sc++;			/* Look at next sigcontext */	if (sc == (struct sigcontext_struct *)(sigctx.regs)) {		/* Last stacked signal - restore registers */		sr = (struct sigregs *) sigctx.regs;		if (copy_from_user(saved_regs, &sr->gp_regs,				   sizeof(sr->gp_regs)))			goto badframe;		saved_regs[PT_MSR] = (regs->msr & ~MSR_USERCHANGE)			| (saved_regs[PT_MSR] & MSR_USERCHANGE);		memcpy(regs, saved_regs, GP_REGS_SIZE);		if (copy_from_user(current->thread.fpr, &sr->fp_regs,				   sizeof(sr->fp_regs)))			goto badframe;		ret = regs->result;	} else {		/* More signals to go */		regs->gpr[1] = (unsigned long)sc - __SIGNAL_FRAMESIZE;		if (copy_from_user(&sigctx, sc, sizeof(sigctx)))			goto badframe;		sr = (struct sigregs *) sigctx.regs;		regs->gpr[3] = ret = sigctx.signal;		regs->gpr[4] = (unsigned long) sc;		regs->link = (unsigned long) &sr->tramp;		regs->nip = sigctx.handler;		if (get_user(prevsp, &sr->gp_regs[PT_R1])		    || put_user(prevsp, (unsigned long *) regs->gpr[1]))			goto badframe;		current->thread.fpscr = 0;	}	return ret;badframe:	do_exit(SIGSEGV);}	/* * Set up a signal frame. */static voidsetup_frame(struct pt_regs *regs, struct sigregs *frame,	    unsigned long newsp){	struct sigcontext_struct *sc = (struct sigcontext_struct *) newsp;	if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))		goto badframe;	if (regs->msr & MSR_FP)		giveup_fpu(current);	if (__copy_to_user(&frame->gp_regs, regs, GP_REGS_SIZE)	    || __copy_to_user(&frame->fp_regs, current->thread.fpr,			      ELF_NFPREG * sizeof(double))	    || __put_user(0x38007777UL, &frame->tramp[0])    /* li r0,0x7777 */	    || __put_user(0x44000002UL, &frame->tramp[1]))   /* sc */		goto badframe;	flush_icache_range((unsigned long) &frame->tramp[0],			   (unsigned long) &frame->tramp[2]);	current->thread.fpscr = 0;	/* turn off all fp exceptions */	newsp -= __SIGNAL_FRAMESIZE;	if (put_user(regs->gpr[1], (unsigned long *)newsp)	    || get_user(regs->nip, &sc->handler)	    || get_user(regs->gpr[3], &sc->signal))		goto badframe;	regs->gpr[1] = newsp;	regs->gpr[4] = (unsigned long) sc;	regs->link = (unsigned long) frame->tramp;	return;badframe:#if DEBUG_SIG	printk("badframe in setup_frame, regs=%p frame=%p newsp=%lx\n",	       regs, frame, newsp);#endif	do_exit(SIGSEGV);}/* * OK, we're invoking a handler */static voidhandle_signal(unsigned long sig, struct k_sigaction *ka,	      siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,	      unsigned long *newspp, unsigned long frame){	struct sigcontext_struct *sc;	struct rt_sigframe *rt_sf;	if (regs->trap == 0x0C00 /* System Call! */	    && ((int)regs->result == -ERESTARTNOHAND ||		((int)regs->result == -ERESTARTSYS &&		 !(ka->sa.sa_flags & SA_RESTART))))		regs->result = -EINTR;	/* Set up Signal Frame */	if (ka->sa.sa_flags & SA_SIGINFO) {		/* Put a Real Time Context onto stack */		*newspp -= sizeof(*rt_sf);		rt_sf = (struct rt_sigframe *) *newspp;		if (verify_area(VERIFY_WRITE, rt_sf, sizeof(*rt_sf)))			goto badframe;		if (__put_user((unsigned long) ka->sa.sa_handler, &rt_sf->uc.uc_mcontext.handler)		    || __put_user(&rt_sf->info, &rt_sf->pinfo)		    || __put_user(&rt_sf->uc, &rt_sf->puc)		    /* Put the siginfo */		    || __copy_to_user(&rt_sf->info, info, sizeof(*info))		    /* Create the ucontext */		    || __put_user(0, &rt_sf->uc.uc_flags)		    || __put_user(0, &rt_sf->uc.uc_link)		    || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)		    || __put_user(sas_ss_flags(regs->gpr[1]), 				  &rt_sf->uc.uc_stack.ss_flags)		    || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)		    || __copy_to_user(&rt_sf->uc.uc_sigmask, oldset, sizeof(*oldset))		    /* mcontext.regs points to preamble register frame */		    || __put_user((struct pt_regs *)frame, &rt_sf->uc.uc_mcontext.regs)		    || __put_user(sig, &rt_sf->uc.uc_mcontext.signal))			goto badframe;	} else {		/* Put another sigcontext on the stack */		*newspp -= sizeof(*sc);		sc = (struct sigcontext_struct *) *newspp;		if (verify_area(VERIFY_WRITE, sc, sizeof(*sc)))			goto badframe;				if (__put_user((unsigned long) ka->sa.sa_handler, &sc->handler)		    || __put_user(oldset->sig[0], &sc->oldmask)#if _NSIG_WORDS > 1		    || __put_user(oldset->sig[1], &sc->_unused[3])#endif		    || __put_user((struct pt_regs *)frame, &sc->regs)		    || __put_user(sig, &sc->signal))			goto badframe;	}	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;badframe:#if DEBUG_SIG	printk("badframe in handle_signal, regs=%p frame=%lx newsp=%lx\n",	       regs, frame, *newspp);	printk("sc=%p sig=%d ka=%p info=%p oldset=%p\n", sc, sig, ka, info, oldset);#endif	do_exit(SIGSEGV);}/* * 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. */int do_signal(sigset_t *oldset, struct pt_regs *regs){	siginfo_t info;	struct k_sigaction *ka;	unsigned long frame, newsp;	if (!oldset)		oldset = &current->blocked;	newsp = frame = 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->state = TASK_STOPPED;			notify_parent(current, SIGCHLD);			schedule();			/* We're back.  Did the debugger cancel the sig?  */			if (!(signr = current->exit_code))				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:				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;				if (!(current->p_pptr->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, regs))					exit_code |= 0x80;				/* FALLTHRU */			default:				sig_exit(signr, exit_code, &info);				/* NOTREACHED */			}		}		if ( (ka->sa.sa_flags & SA_ONSTACK)		     && (! on_sig_stack(regs->gpr[1])))			newsp = (current->sas_ss_sp + current->sas_ss_size);		else			newsp = regs->gpr[1];		newsp = frame = newsp - sizeof(struct sigregs);		/* Whee!  Actually deliver the signal.  */		handle_signal(signr, ka, &info, oldset, regs, &newsp, frame);		break;	}	if (regs->trap == 0x0C00 /* System Call! */ &&	    ((int)regs->result == -ERESTARTNOHAND ||	     (int)regs->result == -ERESTARTSYS ||	     (int)regs->result == -ERESTARTNOINTR)) {		regs->gpr[3] = regs->orig_gpr3;		regs->nip -= 4;		/* Back up & retry system call */		regs->result = 0;	}	if (newsp == frame)		return 0;		/* no signals delivered */	if (ka->sa.sa_flags & SA_SIGINFO)		setup_rt_frame(regs, (struct sigregs *) frame, newsp);	else		setup_frame(regs, (struct sigregs *) frame, newsp);	return 1;}