value in restore_sigcontext. */        regs->frametype = CRIS_FRAME_NORMAL;	/* then some other stuff */	err |= __put_user(mask, &sc->oldmask);	err |= __put_user(usp, &sc->usp);	return err;}/* figure out where we want to put the new signal frame - usually on the stack */static inline void *get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size){	unsigned long sp = rdusp();	/* This is the X/Open sanctioned signal stack switching.  */	if (ka->sa.sa_flags & SA_ONSTACK) {		if (! on_sig_stack(sp))			sp = current->sas_ss_sp + current->sas_ss_size;	}	/* make sure the frame is dword-aligned */	sp &= ~3;	return (void *)(sp - frame_size);}/* grab and setup a signal frame. *  * basically we stack a lot of state info, and arrange for the * user-mode program to return to the kernel using either a * trampoline which performs the syscall sigreturn, or a provided * user-mode trampoline. */static void setup_frame(int sig, struct k_sigaction *ka,			sigset_t *set, struct pt_regs * regs){	struct sigframe *frame;	unsigned long return_ip;	int err = 0;	frame = get_sigframe(ka, regs, sizeof(*frame));	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))		goto give_sigsegv;	err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);	if (err)		goto give_sigsegv;	if (_NSIG_WORDS > 1) {		err |= __copy_to_user(frame->extramask, &set->sig[1],				      sizeof(frame->extramask));	}	if (err)		goto give_sigsegv;	/* Set up to return from userspace.  If provided, use a stub	   already in userspace.  */	if (ka->sa.sa_flags & SA_RESTORER) {		return_ip = (unsigned long)ka->sa.sa_restorer;	} else {		/* trampoline - the desired return ip is the retcode itself */		return_ip = (unsigned long)&frame->retcode;		/* This is movu.w __NR_sigreturn, r9; break 13; */		err |= __put_user(0x9c5f,         (short *)(frame->retcode+0));		err |= __put_user(__NR_sigreturn, (short *)(frame->retcode+2));		err |= __put_user(0xe93d,         (short *)(frame->retcode+4));	}	if (err)		goto give_sigsegv;	/* Set up registers for signal handler */	regs->irp = (unsigned long) ka->sa.sa_handler;  /* what we enter NOW   */	regs->srp = return_ip;                          /* what we enter LATER */	regs->r10 = sig;                                /* first argument is signo */	/* actually move the usp to reflect the stacked frame */	wrusp((unsigned long)frame);	return;give_sigsegv:	if (sig == SIGSEGV)		ka->sa.sa_handler = SIG_DFL;	force_sig(SIGSEGV, current);}static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,			   sigset_t *set, struct pt_regs * regs){	struct rt_sigframe *frame;	unsigned long return_ip;	int err = 0;	frame = get_sigframe(ka, regs, sizeof(*frame));	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))		goto give_sigsegv;	err |= __put_user(&frame->info, &frame->pinfo);	err |= __put_user(&frame->uc, &frame->puc);	err |= copy_siginfo_to_user(&frame->info, info);	if (err)		goto give_sigsegv;	/* Clear all the bits of the ucontext we don't use.  */        err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));	err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));	if (err)		goto give_sigsegv;	/* Set up to return from userspace.  If provided, use a stub	   already in userspace.  */	if (ka->sa.sa_flags & SA_RESTORER) {		return_ip = (unsigned long)ka->sa.sa_restorer;	} else {		/* trampoline - the desired return ip is the retcode itself */		return_ip = (unsigned long)&frame->retcode;		/* This is movu.w __NR_rt_sigreturn, r9; break 13; */		err |= __put_user(0x9c5f,            (short *)(frame->retcode+0));		err |= __put_user(__NR_rt_sigreturn, (short *)(frame->retcode+2));		err |= __put_user(0xe93d,            (short *)(frame->retcode+4));	}	if (err)		goto give_sigsegv;	/* TODO what is the current->exec_domain stuff and invmap ? */	/* Set up registers for signal handler */	regs->irp = (unsigned long) ka->sa.sa_handler;  /* what we enter NOW   */	regs->srp = return_ip;                          /* what we enter LATER */	regs->r10 = sig;                                /* first argument is signo */        regs->r11 = (unsigned long) &frame->info;       /* second argument is (siginfo_t *) */        regs->r12 = 0;                                  /* third argument is unused */	/* actually move the usp to reflect the stacked frame */	wrusp((unsigned long)frame);	return;give_sigsegv:	if (sig == SIGSEGV)		ka->sa.sa_handler = SIG_DFL;	force_sig(SIGSEGV, current);}/* * OK, we're invoking a handler */	static inline voidhandle_signal(int canrestart, unsigned long sig, struct k_sigaction *ka,	      siginfo_t *info, sigset_t *oldset, struct pt_regs * regs){	/* Are we from a system call? */	if (canrestart) {		/* If so, check system call restarting.. */		switch (regs->r10) {			case -ERESTARTNOHAND:				/* ERESTARTNOHAND means that the syscall should only be				   restarted if there was no handler for the signal, and since				   we only get here if there is a handler, we dont restart */				regs->r10 = -EINTR;				break;			case -ERESTARTSYS:				/* ERESTARTSYS means to restart the syscall if there is no				   handler or the handler was registered with SA_RESTART */				if (!(ka->sa.sa_flags & SA_RESTART)) {					regs->r10 = -EINTR;					break;				}			/* fallthrough */			case -ERESTARTNOINTR:				/* ERESTARTNOINTR means that the syscall should be called again				   after the signal handler returns. */				RESTART_CRIS_SYS(regs);		}	}	/* Set up the stack frame */	if (ka->sa.sa_flags & SA_SIGINFO)		setup_rt_frame(sig, ka, info, oldset, regs);	else		setup_frame(sig, ka, oldset, regs);	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);	}}/* * 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. * * Also note that the regs structure given here as an argument, is the latest * pushed pt_regs. It may or may not be the same as the first pushed registers * when the initial usermode->kernelmode transition took place. Therefore * we can use user_mode(regs) to see if we came directly from kernel or user * mode below. */int do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs){	siginfo_t info;	struct k_sigaction *ka;	/*	 * 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(regs))		return 1;	if (!oldset)		oldset = &current->blocked;	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:				lock_kernel();				sig_exit(signr, exit_code, &info);				/* NOTREACHED */			}		}		/* Whee!  Actually deliver the signal.  */		handle_signal(canrestart, signr, ka, &info, oldset, regs);		return 1;	}	/* Did we come from a system call? */	if (canrestart) {		/* Restart the system call - no handlers present */		if (regs->r10 == -ERESTARTNOHAND ||		    regs->r10 == -ERESTARTSYS ||		    regs->r10 == -ERESTARTNOINTR) {			RESTART_CRIS_SYS(regs);		}	}	return 0;}